Researchers Database

AONO, Hiromichi

    Graduate School of Science and Engineering Materials Science and Biotechnology Professor
Last Updated :2020/11/10

Researcher Information

J-Global ID

Research Interests

  • ゼオライト   磁性材料   微粒子材料   化学センサ   固体電解質   Chemical Sensor   Solid Electrolyte   

Research Areas

  • Nanotechnology/Materials / Green/sustainable/environmental chemistry
  • Nanotechnology/Materials / Inorganic materials

Academic & Professional Experience

  • 2015/07 - Today  Ehime UniversityGraduate School of Science and Engineering教授
  • 2007/04 - 2015/06  Ehime UniversityGraduate School of Science and Engineering准教授
  • 2001/04 - 2007/03  Ehime UniversityFaculty of Engineering, Department of Materials Science and Engineering助教授
  • 2001/09 - 2001/10  ローマ大学”Tor Vergata”訪問研究員(文部科学省在外研究員)
  • 1998/04 - 2001/03  Ehime UniversityFaculty of Engineering, Department of Materials Science and Engineering講師
  • 1996/10 - 1998/03  Ehime UniversityFaculty of Engineering, Department of Materials Science and Engineering助手
  • 1986/04 - 1996/09  Niihama National College of Technology工業化学科助手
  • 1988/05 - 1989/02  Osaka UniversitySchool of Engineering

Education

  • 1994/04 -   大阪大学から博士(工学)の学位を受ける
  •        - 1986  Ehime University  Faculty of Engineering  工業化学科
  •        - 1986  Ehime University  Faculty of Engineering

Association Memberships

  • ATOMIC ENERGY SOCIETY OF JAPAN   日本希土類学会   日本セラミックス協会   化学センサ研究会   電気化学会   日本化学会   

Published Papers

  • Effect of coexisting lithium content on fluorescent properties of silver ion-exchanged LTA zeolite
    H. Aono, K. Yahara, E. Johan, and Y. Itagaki
    J. Ceram. Soc. Jpn. 128 (10) 670 - 676 2020/10 [Peer-reviewed]
     Scientific journal
  • Hexagonal boron nitride auxiliary electrode for YSZ based hydrogen sensor
    Y. Itagaki, E. Sarumaru, H. Aono
    J. Ceram. Soc. Jpn. 128 (7) 427 - 430 2020/07 [Peer-reviewed]
     Scientific journal
  • Synthesis of chabazite and merlinoite from chemical reagents for Cs+ adsorption and immobilization properties by heat-treatment
    Hiromichi Aono, Yuta Takeuchi, Yoshiteru Itagaki, Erni Johan
    Solid State Sciences 100 (106094) 2020/02 [Peer-reviewed]
     Scientific journal
  • 六方晶窒化ホウ素を電極補助層に用いるアンモニア検知
    板垣吉晃, 川淵貴史, 猿丸英理, 青野宏通
    分析化学 68 (12) 937 - 943 2019/12 [Peer-reviewed]
     Scientific journal
  • Whitish fluorescence of partially Ag-exchanged zeolite Y affected by coexisting cations
    Erni Johan, Yasutaka Kanda, Naoto Matsue, Yoshiteru Itagaki, Hiromichi Aono
    Journal of Luminescence 213 482 - 488 2019/09 [Peer-reviewed]
     Scientific journal
  • Tomomasa Sakai, Hideyuki Hirazawa, Deleg Sangaa, Uyanga Enkhnaran, Hiromichi Aono
    MATERIALS TODAY-PROCEEDINGS 16 (1) 206 - 210 2214-7853 2019 [Peer-reviewed]
     International conference proceedings 
    The spinel type MgFe2O4 ferrite powder having self-heating ability in an AC magnetic field was prepared by polymerization method in order to investigated the application for thermal coagulation treatment of cancer tissue. The single phase of cubic ferrite structure was obtained for all sample synthesized with different CA/MN (Citric Acid / Metal Nitrate) conditions. The heat-generation-ability was extremely improved at CA/MN=2.0 sample (Delta T = 168 degrees C), however the heat-generation-property decreased with increase in CA/MN ratio. Hysteresis loss value also increased at CA/MN=2.0 sample, it was suggested that the heat-generation-ability of MgFe2O4 powder prepared by polymerization method was depended on hysteresis loss value. (C) 2019 Elsevier Ltd. All rights reserved.
  • Effect of Ni-loading on Sm-doped CeO2 anode for ammonia-fueled solid oxide fuel cell
    Y. Itagaki, J. Cui, N. Ito, H. Aono, H. Yahiro
    J. Ceram. Soc. Jpn. 126 (10) 870 - 876 2018/10 [Peer-reviewed]
     Scientific journal
  • Cs+ Decontamination Properties of Mordenites and Composite Materials Synthesized from Coal Fly Ash and Rice Husk Ash
    H. Aono, T. Kunimoto, R. Takahashi, Y. Itagaki, E. Johan, N. Matsue
    Journal of Asian Ceramic Societies 6 (3) 213 - 221 2018/09 [Peer-reviewed]
     Scientific journal
  • Hiromichi Aono, Ryuichiroh Takahashi, Yoshiteru Itagaki, Erni Johan, Naoto Matsue
    Journal of Nuclear Materials 508 20 - 25 0022-3115 2018/09 [Peer-reviewed]
     Scientific journal 
    The Cs ion was partially adsorbed (4.0% in all of the alkali cation sites) on natural mordenite as a simulated decontamination, then heat-treated to immobilize the Cs in the decomposed zeolite. Although the mordenite phase was maintained for the samples even heated at 800 °C, a glassy amorphous phase formed due to the decomposition of the mordenite at 900 °C. In the case of the non-treated sample, 3.6% Cs ion from all of the adsorbed Cs was eluted by a dissolution test in deionized water for 14 days. The elution ratio of the Cs ion decreased by the heat treatment. The Cs ion did not elute when the sample was heated at 1000 °C and higher temperature due to the Cs containment in the glassy phase. Na2CO3 powder was mixed with the mordenite for lowing the glass-forming temperature. The mordenite mixed with Na2CO3 had a lower melting point and immobilized the Cs at 900 °C. The Cs evaporation during the heating was also depressed by the Na2CO3 addition.
  • Electrophoretically Deposited Ni-Loaded (SmO1.5)0.2(CeO2)0.8 Anode for Ammonia-Fueled Solid Oxide Fuel Cell E01: Electrodeposition of Micro and Nano Materials for Batteries and Sensors
    Yoshiteru Itagaki, Jiang Cui, Naoto Ito, Hiromichi Aono, Hidenori Yahiro
    ECS Transactions 85 (13) 779 - 786 2018/04 [Peer-reviewed]
     Scientific journal
  • Harinarayan Das, Akihiro Inukai, Nipa Debnath, Takahiko Kawaguchi, Naonori Sakamoto, Sheikh Manjura Hoque, Hiromichi Aono, Kazuo Shinozaki, Hisao Suzuki, Naoki Wakiya
    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS 112 179 - 184 0022-3697 2018/01 [Peer-reviewed]
     Scientific journal 
    In this paper, we report a detailed study of magnetic properties and AC magnetic heat generation characteristics of La0.77Sr0.23MnO3 (LSMO) nanoparticles to investigate appropriate crystallite size with a view to the proper application of self-controlled magnetic hyperthermia treatments of cancer. A series of nanocrystalline LSMO manganite was synthesized through the chemical route called as "polymerized complex method" and then subsequently annealed at the different temperature from 600 to 1400 degrees C to obtain various crystallite size. Phase formation and crystal structure of the prepared powder were determined by the powder X-ray diffraction (XRD) using Rietveld analysis. The XRD patterns reveal that all powder samples are a single phase rhombohedral perovskite-like structure with R (3) over barc space group. The mean crystallite size of prepared particles varied from 19 to 243.8 nm with the increase of the annealing temperature starting from 600 to 1400 degrees C. The field emission scanning electron microscopy (FE-SEM) analysis shows the surface morphology with a strong agglomeration of fine nanoparticles. The Magnetic study reveals that these nanoparticles exhibit ferromagnetic nature with different value of magnetization, coercivity, Curie temperature which is strongly dependent on their crystallite size. The maximum saturation temperature (Ts = 66 degrees C) under AC magnetic field (H = 1.77 kA/m, f = 370 kHz) was found for the crystallite size of 39.5 nm due to its pure single domain phase. Such LSMO nanoparticles, having the higher heating rate, can be used in magnetically induced hyperthermia cancer treatment.
  • Harinarayan Das, Nipa Debnath, Atsushi Toda, Takahiko Kawaguchi, Naonori Sakamoto, Hiromichi Aono, Kazuo Shinozaki, Hisao Suzuki, Naoki Wakiya
    ADVANCED POWDER TECHNOLOGY 28 (7) 1696 - 1703 0921-8831 2017/07 [Peer-reviewed]
     Scientific journal 
    The superparamagnetic magnesium ferrite (MgFe2O4) dense nanospheres are synthesized by ultrasonic spray pyrolysis (USP) method from different concentrations of the initial precursor solution. The effect of precursor solution concentration on the particle's size, morphology, and superparamagnetic behavior has been investigated. XRD results confirm that studied precursor concentration (0.06, 0.12 and 0.24 M) exhibited single phase cubic structure. The mean crystallites size (called as primary particles) of 0.06, 0.12 and 0.24 M samples are 9.6, 11.5, 11.0 nm, respectively but the entire nanosphere's diameter (called as secondary particles) increases from 206 to 340 nm with increasing precursor concentration. TEM analysis also reveals that nanospheres consist of densely aggregated crystallites of spherical shape and smooth surface. The value of polydispersity index (PDI) shows narrower size distribution for lower concentration. Magnetic properties indicate the superparamagnetic nature for all samples. Herein, the appropriate induction heat generation rate with better morphology was obtained for 0.06 M concentration. Ion release in the aqueous solution of the composition (about 95% for Mg; 99% for Fe) indicating better stability has been confirmed by ICP-OES test. In this approach, as-synthesized nanospheres are suitable for using as a heating agent in magnetic thermotherapy application. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
  • Yoshiteru Itagaki, Akinori Hiraoka, Hiromichi Aono, Hidenori Yahiro
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 125 (4) 338 - 342 1882-0743 2017/04 [Peer-reviewed]
     Scientific journal 
    Hydrogen permeation properties of Gd0.1Ce0.9Ox/BaCe0.80Y0.20O3-delta (GDC/BCY) dual-phase membranes were evaluated. Nongalvanic hydrogen permeation was observed for 46 vol% GDC-containing BCY membranes: the permeation rate was 0.30 ml.min(-1).cm(-2) at 800 degrees C. This is almost comparable to the reported value of Ni-BCY cermet (0.50 ml.min(-1).cm(-2)). This nongalvanic hydrogen permeation unambiguously indicates that the BCY-GDC composite functions as a mixed proton-electron conductor in an H-2 reducing atmosphere. From a conductivity analysis, it was deduced that 46 vol% GDC/BCY possesses proton and electron conductivities comparable to the bulk states of BCY and GDC. The composite membrane was stable in an atmosphere switching between H-2 and air. TGA analysis indicated that addition of GDC enhanced the stability of the BCY phase in CO2. (C) 2017 The Ceramic Society of Japan. All rights reserved.
  • Hiromichi Takebe, Sengo Kobayashi, Hiromichi Aono, Saeki Yamamuro
    Nanostructures for Novel Therapy: Synthesis, Characterization and Applications 81 - 106 2017/03 In book 
    Pearl shells, which are yielded as a waste during jewel pearl culture process at Uwajima sea in Ehime prefecture, Japan, are micro-/nanostructured composite materials alternatively consisting of organic and inorganic CaCO3 layers with nanothicknesses. Micro-/nanosized pearl particles are candidates for Ca nutrients and hydroxyapatite (HAp) formation. Iron oxide nanocubes with surfactant are self-assembled into closed packing structures. The integrated structure of thermal-imprinted glass templates with functional nanoparticles becomes a potential candidate for new therapeutic nanostructures. Magnetic Y3Fe5O12 and Fe3O4 particles prepared by either break down or built-up processes were evaluated for thermal coagulation therapy. The dissolution behavior of micrometer-sized pearl powder was also evaluated in artificial stomach acid at 37°C. Future directions of micro-/nanostructured materials are proposed for biomedical applications.
  • Hiromichi Aono
    Journal of the Society of Powder Technology, Japan 54 (8) 524 - 526 1883-7239 2017 [Invited]
     Scientific journal 
    The decontamination of Cs in rice fields is necessary for the continuation of agriculture in the Fukushima prefecture. A composite material consisting of the Na-P1 type zeolite and magnetite was synthesized from the fly-ash and iron chlorides, because the magnetic collection was possible using this composite material after radioactive Cs+ ion adsorption. The existence of nano-sized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by SEM and TEM observations. By mixing soil with the magnetized Na-P1, with the mass ratio of 10:1, in ammonium oxalate solution for 10 min, more than 80% of radioactive Cs was removed from soil. The composite powder material consisting of mordenite and nano-sized magnetite was also synthesized from a mixed slurry of the diatomite and nanosized magnetite.
  • Yoshiteru Itagaki, Yuga Yamamoto, Hiromichi Aono, Hidenori Yahiro
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 125 (6) 528 - 532 1882-0743 2017 [Peer-reviewed]
     Scientific journal 
    Anode-supported solid oxide fuel cells with a thin layer of proton conducting BaCe0.8Y0.2O3- (BCY) were fabricated by electrophoretic deposition technique using an organic suspension. BCY green films were formed on a graphite-added NiO-BCY substrate. By the classification of particle size distribution by the suitable period of sedimentation yielded a crack-free green film. Sintering of the crack-free green film at 1450 degrees C yielded a dense layer of BCY with the thickness of about 9.2 +/- 0.3 mu m after sintering at 1450 degrees C. The BCY thin film on the NiO-BCY substrate exhibited conductivity of 1.6 x 10(12)S.cm(-1) at 600 degrees C and its activation energy was 0.35 eV. The anode-supported single cell with the BCY thin film resulted in the maximum power density of 74.2mW.cm(-2) at 600 degrees C. (C) 2017 The Ceramic Society of Japan. All rights reserved.
  • 脇谷 尚樹, ダス ハリナラヤン, 川口 昂彦, 坂元 尚紀, 鈴木 久男, 青野 宏通, 篠崎 和夫
    工業材料 日刊工業出版プロダクション ; 1955- 64 (12) 36 - 41 0452-2834 2016/12 Scientific journal
  • Hiromichi Aono, Yuhi Yamano, Takashi Naohara, Yoshiteru Itagaki, Tsunehiro Maehara, Hideyuki Hirazawa
    JOURNAL OF ADVANCED CERAMICS 5 (3) 262 - 268 2226-4108 2016/09 [Peer-reviewed]
     Scientific journal 
    Composite powder material of the Y3Fe5O12-nSiC system was synthesized by a reverse coprecipitation method to study its heat generation property in an AC magnetic field. For Y3Fe5O12 (n = 0), the maximum heat generation ability of 0.45 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the sample calcined at 1100 degrees C. The SiC addition helped to suppress the particle growth for Y3Fe5O12 at the calcination temperature. The heat generation ability was improved by the addition of the SiC powder, and the maximum value of 0.93 W.g(-1) was obtained for the n = 0.3 sample calcined at 1250 degrees C. The heat generation ability and the hysteresis loss value were proportional to the cube of the magnetic field (H-3). The heat generation ability (W.g(-1)) of the Y3Fe5O12-0.3SiC sample calcined at 1250 degrees C could be expressed by the equation 4.5x10(-4).f.H-3 using the frequency f(kHz) and the magnetic field H(kA.m(-1)).
  • Hiromichi Aono, Noriaki Kaji, Yoshiteru Itagaki, Erni Johan, Naoto Matsue
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 124 (5) 617 - 623 1882-0743 2016/05 [Peer-reviewed]
     Scientific journal 
    Mordenite was synthesized using chemical reagents of amorphous SiO2 and sodium aluminate without the addition of a template agent and a seed powder. The single phase of the mordenite was obtained for the Al/Si ratios of 0.085-0.120 as the starting material in the reaction temperature range of 170-200 degrees C for 24 h. The cation exchange capacity (CEC) was ca. 180-210 cmol/kg and it increased with the Al/Si ratio. The Cs+ adsorption ability from 100ppm Cs+ 100mL solutions of water and seawater for the mordenite (1.0 g) was > 99% and ca. 85-92%, respectively. A composite material consisting of the mordenite and magnetite (10, 20, 30 wt%) was synthesized for the magnetic collection. The total Cs decontamination rates using the magnetic collection material after the Cs+ adsorption in water were also higher than 95% for all the examined magnetite-containing composite materials. (C) 2016 The Ceramic Society of Japan. All rights reserved.
  • Erni Johan, Kiyotoshi Ogami, Naoto Matsue, Yoshiteru Itagaki, Hiromichi Aono
    ARPN Journal of Engineering and Applied Sciences 11 4006 - 4010 2016/03 [Peer-reviewed]
     Scientific journal 
    © 2006-2016 Asian Research Publishing Network (ARPN). A white rice husk ash with a silica content of more than 99% was produced from a rice husk by a citric acid treatment before heating the rice husk at 700 °C to 1000 °C. The white ash mostly consisted of an amorphous phase, and cristobalite usually found after heating rice husk was not detected. The amorphous phase was still formed although the rice husk was burned at 1000 °C. These indicated that the citric acid dissolved part of the carbon compounds in the rice husk, followed by releasing of potassium and other alkali cations, and as a result, an amorphous high silica ash was formed without incorporation of crystal phases such as cristobalite. The white rice husk ash was successfully converted into ZSM-5, a zeolite widely used as a catalyst in the petroleum industries.
  • Hideyuki Hirazawa, Yoshiki Ito, Deleg Sangaa, Namsrai Tsogbadrakh, Hiromichi Aono, Takashi Naohara
    FRONTIERS IN MATERIALS SCIENCE (FMS2015) 1763 (020009) 1 - 4 0094-243X 2016 [Peer-reviewed]
     International conference proceedings 
    Al substituted MgAlXFe2-XO4 that have high heat generation ability in the AC magnetic field was obtained by Sol-Gel method. The heat generation ability was improved by Al3+ substitution, the highest heat generation property (Delta T = 127.2 degrees C) was confirmed for X=0.25 sample. This high heat generation ability was depended on hysteresis loss value, the hysteresis loss for X=0.25 samples were significantly increased in the AC magnetic field.
  • Hiromichi Aono, Taiga Nagamachi, Takashi Naohara, Yoshiteru Itagaki, Tsunehiro Maehara, Hideyuki Hirazawa
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 124 (1) 23 - 28 1882-0743 2016/01 [Peer-reviewed]
     Scientific journal 
    The synthesis conditions of a nano-sized magnetite powder using a reverse coprecipitation method were studied in order to control the particle size and the heat generation ability in an AC magnetic field for thermal coagulation therapy. A low temperature reaction and high concentration of the mixed irons as the starting materials in solution increased the particle size of the magnetite powder. The particle size decreased with an increase in the concentration of the coexisting Na+ and Cl- ions. The particle size was enhanced with an increase in the R = Fe2+/(Fe2+ + Fe3+) molar ratio of the divalent iron, and the maximum heat generation ability was obtained at the R = 0.33 molar ratio. The maximum heat generation ability of 0.25-0.28 W.g(-1) in the AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the magnetite having an ca. 13-14 nm particle size. (C) 2016 The Ceramic Society of Japan. All rights reserved.
  • Erni Johan, Yohei Yamauchi, Naoto Matsue, Yoshiteru Itagaki, Hiromichi Aono
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 124 (1) 70 - 73 1882-0743 2016/01 [Peer-reviewed]
     Scientific journal 
    A luminescent material free of rare earth elements was prepared from a partially Ag+ exchanged zeolite X. One gram of a commercially available zeolite X (Na+ form) was mixed with 100 mL of AgNO3 aqueous solutions of 2.0 to 50 mmol/L. The mixtures were shaken for 24 h, then the solid products were separated and dried at 50 degrees C. Some of the products were heated at 100 to 800 degrees C in atmospheric air. Luminescence was observed from the products with Ag loadings of 0.5 mmol/g or higher. These products showed yellow luminescence under UV light excitations of 254 and 312 nm. The luminescent products showed two excitation bands with peak maxima at 271 and 311 nm, and a single emission band at 550 nm. The luminescence intensity was low for the 0.5 mmol/g Ag loaded sample, but it significantly increased with the increasing amounts of Ag+ up to a 1.0 mmol/g loading, then a quenching occurred with a further increased Ag+ loading. Heating of the Ag-loaded zeolite X decreased the luminescence intensity. Heating the Ag loaded zeolite X at 800 degrees C resulted in a low blue luminescence intensity due to collapsing the zeolite X structure into an amorphous phase. This study suggested that a luminescent material free of rare earth elements can be fabricated from Ag-exchanged zeolite X without any heat treatment. The highest luminescence intensity was attained at the Ag loading of 1.0 mmol/g, along with a measured internal quantum efficiency of 20.8% (lambda ex. = 311 nm). (C) 2016 The Ceramic Society of Japan. All rights reserved.
  • Hiromichi Aono, Keisuke Kanayama, Erni Johan, Yoshiteru Itagaki, Naoto Matsue
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 124 (1) 82 - 84 1882-0743 2016/01 [Peer-reviewed]
     Scientific journal 
    Partially Ag-exchanged Na-P1 type zeolites were prepared using an Na-P1 type zeolite and a silver nitrate solution. Emission spectra of the samples prepared at various concentrations of the silver nitrate solution and at various subsequent heat-treatment temperatures were compared. The structure of the Na-P1 type zeolites was changed to an amorphous phase by the heat-treatment at 400 degrees C or higher. When the amorphous materials were irradiated with 254 nm ultraviolet light, these samples showed a high intensity violet luminescence with an emission peak around 390 nm. (C)2016 The Ceramic Society of Japan. All rights reserved.
  • Erni Johan, Kohei Yoshida, Moses Wazingwa Munthali, Naoto Matsue, Yoshiteru Itagaki, Hiromichi Aono
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 123 (1444) 1065 - 1072 1882-0743 2015/12 [Peer-reviewed]
     Scientific journal 
    The radioactive decontamination of water, soil and other materials requires cheap and effective adsorbents. Artificial zeolites synthesized from an industrial waste (coal fly ash: Na-P1 type zeolite) and a natural material ( diatomite: mordenite type zeolite) have a high Cs+ adsorptivity in the adsorption experiments using 0.1 g of the zeolite and 50 mL of up to 7.5 mM CsCl. The coexisting cation suppressed the Cs+ adsorption onto the zeolites, and the effect of the suppression was in the order, K+ > Na+ > Ca2+ > Mg2+. A thermodynamic analysis proved that the Cs+ adsorption onto the two zeolites was exothermic favoring a lower temperature. The artificial mordenite showed a greater Cs+ adsorption strength, higher distribution coefficient and lower Delta G degrees, especially at low Cs+ concentrations. Adsorption isotherm analysis by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models showed a greater Cs+ adsorption selectivity for the artificial mordenite even at a low pH. (C) 2015 The Ceramic Society of Japan. All rights reserved.
  • Adsorption Selectivity of Cs+ and Sr2+ by Zeolites Affected by Coexistence Cation in Relation to Radioactive Decontamination
    M. W. Munthali, E. Johan, H. Aono, N. Matsue
    Journal of Asian Ceramic Societies 3 (3) 245 - 250 2015/10 [Peer-reviewed]
     Scientific journal
  • Yoshiteru Itagaki, Kenta Fujihashi, Hiromichi Aono, Masami Mori, Yoshihiko Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 123 (1442) 961 - 966 1882-0743 2015/10 [Peer-reviewed]
     Scientific journal 
    Sm2O3/SmFeO3 mixed powders were applied to a chemo-resistive VOC (volatile organic compound) gas sensor. The sensor response to 30 ppm toluene gas increased with increasing the Sm2O3 content up to 30 wt%, but decreased by further adding. The addition of Sm2O3 up to 30 wt% also enhanced the catalytic activity for toluene oxidation, as the result of the sensor response. The amount of toluene adsorption increased with increase in the surface Sm concentration. It was concluded that adding Sm2O3 increased the amount of adsorbed VOCs, resulting in the enhancement of the sensor response and the catalytic activity. Furthermore, adding Sm2O3 remarkably shortened the recovery time from the VOCs to air. For the ethanol sensing, adding Sm2O3 was only effective on shortening the recovery time. (C) 2015 The Ceramic Society of Japan. All rights reserved.
  • Hideyuki Hirazawa, Syo Yoshikawa, Hiromichi Aono, Takashi Naohara, Tsunehiro Maehara, Yuji Watanabe
    CHEMISTRY LETTERS 44 (10) 1298 - 1299 0366-7022 2015/10 [Peer-reviewed]
     Scientific journal 
    Y3Fe5O12 ferrite powder with addition of La having high heat generation ability in an AC magnetic field was prepared by reverse coprecipitation method. The highest heat generation temperature was obtained for the La 0.3 mol added sample calcined at 1150 degrees C.
  • Harinarayan Das, Naonori Sakamoto, Hiromichi Aono, Kazuo Shinozaki, Hisao Suzuki, Naoki Wakiya
    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 392 91 - 100 0304-8853 2015/10 [Peer-reviewed]
     Scientific journal 
    In this paper, we present the synthesized of magnesium ferrite (MgFe2O4) nano -spheres by a single-step ultrasonic spray pyrolysis (USP) technique from the aqueous metal nitrate precursor solution without any organic additives or post annealing processes. The effects of different pyrolysis temperatures on the particles size, morphology and their superparamagnetic behavior have been investigated to evaluate the heat generation efficiency in an AC magnetic field. The X-ray powder diffraction spectra of MgFe2O4 nano-spheres synthesized at the pyrolysis temperatures of 600, 700, 800 and 900 degrees C exhibited single phase cubic structure and obtained mean crystallite size (primary particles) of 4.05, 9.6, 15.97 and 31.48 nm, respectively. Transmission electron microscopy (TEM) confirms that the particles consisted of aggregates of the primary crystallite had densely congested spherical morphology with extremely smooth surface appearance. Field emission electron microscopy (FESEM) reveals that the shape and size of the nano-spheres (secondary particles) does not change significantly but the degree of agglomeration between the secondary particles was reduced with increasing the pyrolysis temperature. The average size and size distribution of nano-spheres measured using electrophoretic scattering photometer have found very low polydispersity index (PK for all samples. The field dependent magnetization studies indicated superparamagnetic nature for the particles having crystallite size i.e. 4.05 and 9.6 nm and exhibited ferromagnetic nature for 15.97 and 3148 nm. It is also demonstrated that, as the pyrolysis temperature increases, the saturation magnetization of the MgFe2O4 nanopowders increases due to enhancement of crystallites. The shift in Curie temperature is well described by the finite-size scaling formula. The magnetically loss heating values of selected samples in crystallite size of 9.6 and 15.97 nm were investigated by measuring the time dependent temperature curves in an external alternating magnetic field (370 kHz, 1.77 kA/m). The more heat generation ability was obtained for 9.6 nm in crystal size because of minimum squareness ratio with coercivity in superparamagnetic range. The results reported in this study are useful to find out of superparamagnetic limit for the preparation of MgFe2O4 nanopowders. (C) 2015 Elsevier B.V. All rights reserved.
  • Hiromichi Aono, Yuhi Yamano, Tadahiko Nishimori, Takashi Naohara, Yoshiteru Itagaki, Tsunehiro Maehara, Hideyuki Hirazawa
    CERAMICS INTERNATIONAL 41 (7) 8461 - 8467 0272-8842 2015/08 [Peer-reviewed]
     Scientific journal 
    Ferrimagnetic Y3Fe5O12 powder was synthesized by a reverse coprecipitation method in order to study its heat generation property in an AC magnetic field. An orthorhombic YFeO3 phase having a small particle size (<100 nm) was obtained for the samples calcined at a low temperature. The maximum heat generation ability in an AC magnetic field was obtained for the Y3Fe5O12 ferrite powder by calcination at 1100 degrees C. The heat generation ability was reduced for the samples calcined at a higher temperature. The particle growth with the formation of the cubic single phase might influence the heat generation ability. The heat generation ability and the hysteresis loss value were proportional to the cube of the magnetic field (H-3), because the coercivity value of the B-H curve was proportional to the square of the amplitude of the AC magnetic field (H-2). The heat generation ability (W g(-1)) of the Y3Fe5O12 sample sintered at 1100 degrees C can be expressed by the equation 2.2 x 10(-4).f.H-3 using the frequency (f/kHz) and the magnetic field (H/kA m(-1)), which has the highest heat generation ability of the reported magnetic materials. The hysteresis loss value for the B-H curve agreed with the heat generation ability of the samples calcined at 1100 degrees C and lower temperatures. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
  • 磁化ゼオライトを用いた土壌中の放射性セシウム除去技術
    青野 宏通
    放射性物質対策技術集成 49 - 57 2015/04 [Invited]
     Research society
  • Keizo Yamada, Erni Johan, Naoto Matsue, Yoshiteru Itagaki, Hiromichi Aono
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 123 (1435) 129 - 135 1882-0743 2015/03 [Peer-reviewed]
     Scientific journal 
    Mordenite was artificially synthesized using various diatomites for radioactive Cs decontamination. A high CEC (Cation Exchange Capacity) value was obtained when the diatomite had a high Al/Si elemental ratio. The Cs+ adsorption rate from 100 ppm Cs solution for the synthesized mordenite (1.0 g) was ca. 100% and ca. 83% in 100 mL of water and seawater, respectively. The composite powder material consisting of mordenite and nano-sized magnetite was synthesized from a mixed slurry of the diatomite and nano-sized magnetite. Magnetic collection rate for the composite material using a neodymium magnet was larger than 90% for the 20 and 30 wt% magnetite-containing composite materials. The total Cs decontamination rates using magnetic collection after the Cs+ adsorption in water were 92.7% and 97.2% for the 20 and 30 wt% magnetite-containing composite material, respectively. (C) 2015 The Ceramic Society of Japan. All rights reserved.
  • Erni Johan, Toshio Yamada, Moses Wazingwa Munthali, Ponyadira Kabwadza-Corner, Hiromichi Aono, Naoto Matsue
    5th Sustainable Future for Human Security (SustaiN 2014) 28 52 - 56 1878-0296 2015 [Peer-reviewed]
     International conference proceedings 
    Adsorption experiments of Cs+ were carried out by using two natural zeolites, namely mordenite and clinoptilolite. The same experiments were also conducted by using synthetic zeolite A, synthetic zeolite X, and artificial zeolite Na-P1 as references. The purpose of this study was to investigate the potential of natural zeolites on the adsorption of radioactive Cs+. The results indicated that although cation exchange capacity of the natural zeolites was much lower compared to the synthetic and artificial zeolites, the adsorption capacity of Cs+ was much greater than the synthetic and artificial zeolites. The order of the adsorption capacity of Cs+ was mordenite>clinoptilolite> Na-P1 >> zeolite A > zeolite X. It indicates that natural zeolites are promising materials in the removal of radioactive Cs+. 2015 The Authors. Published by Elsevier B.V.
  • 吉田昂平, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通
    環境放射能除染学会誌 2 (3) 175 - 183 2187-8382 2014/09
  • バーミキュライトを模擬土壌としたセシウム除染条件の検討, 吉田昂平,エルニ ジョハン
    青野 宏通
    環境放射能除染学会誌 2 (3) 165 - 174 2014/08 [Peer-reviewed]
     Scientific journal
  • セシウム除去に有効なゼオライト・ガン治療に有望な機能性材料の開発
    青野 宏通
    愛媛大学研究室からこんちには!8 8 230 - 243 2014/04 [Invited]
     Research society
  • 放射性Cs除染を目的としたゼオライト・マグネタイト複合材料
    青野 宏通
    セラミックデータブック2014/15 42 (96) 70 - 73 2014/04 [Invited]
     Research society
  • Hiromichi Aono
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 122 (1424) 237 - 243 1882-0743 2014/04 Scientific journal 
    Thermal coagulation therapy using powdered magnetic materials in an alternating (AC) magnetic field has been expected as a treatment of cancerous tissues. For nano-sized superparamagnetic particles, the magnetic energy is mainly converted to a heat generation ability by the rotation of the magnetic moment (Neel relaxation) along with the rotation of the particles (Brownian relaxation). Fe3O4 (magnetite) nanoparticles have been mainly investigated as the candidate material for this type of therapy. In this review, an outline of the ferrite materials having heat generation ability in the AC magnetic field is described for the application of the thermal coagulation therapy. In particular, I focused on the preparation of a nano-sized magnetic material using physical bead milling to develop a magnetic material of Y3Fe5O12 and its high heat generation ability. The preparation of Y3Fe5O12 microspheres with a 20-32 mu m diameter range using the bead-milled powder was also described for the embolization method of cancer treatment. (C) 2014 The Ceramic Society of Japan. All rights reserved.
  • 磁化ゼオライトによる放射性セシウム吸着技術について
    青野 宏通
    放射性物質の吸着・除染および耐放射線技術における材料,施工,測定の新技術, 技術情報協会 145 - 152 2014 [Invited]
     Research society
  • Hiromichi Aono, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa
    INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS 44 (2) 227 - 234 1383-5416 2014 [Peer-reviewed]
     Scientific journal 
    Nano-sized superparamagnetic Y3Fe5O12 ferrite having a high heat generation ability in an AC magnetic field was prepared by physical bead milling. The highest heat ability in the AC magnetic field was for the fine Y3Fe5O12 powder with a 16-nm crystallite size (the samples were milled for 4 h using 0.1 mm phi beads). The main reason for the high heat generation property of the milled samples was ascribed to an increase in the Neel relaxation of the superparamagnetic material. For the samples milled for 4 h using 0.1 mmf beads, the heat generation ability (W.g(-1)) was estimated using a 3.58 x 10(-4).f.H-2 frequency (f/kHz) and the magnetic field (H/kA.m(-1)), which is the highest reported value of superparamagnetic materials. Furthermore, Y3Fe5O12 microspheres having a 20-32 mu m diameter range were prepared by a spray dryer using the bead-milled nano-sized particles.
  • Tadahiko Nishimori, Yusuke Akiyama, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yoshiteru Itagaki, Hiromichi Aono
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 122 (1421) 35 - 39 1882-0743 2014/01 [Peer-reviewed]
     Scientific journal 
    Nano-sized Y3Fe5O12-nSmFeO(3) mixed powder (ca. 20 nm in particle size) was prepared by bead-milling using 0.05 mm phi beads for 10 h. For the SmFeO3-free sample (n = 0), the heat generation ability in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was 0.34 W.g(-1) for the bead-milled sample, and it was increased by a calcination at low temperature. The maximum ability of 0.46 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the Y3Fe5O12 (n = 0) sample (36.8 nm in particle size) calcined at 700 degrees C. The heat generation mechanism changed from superparamagnetic to ferrimagnetic due to particle growth at 700 degrees C for the n = 0 sample, because the heat generation ability (W.g(-1)) depended on the cube of the magnetic field. A mixed SmFeO3 phase acted as an impurity for depression of the particle growth for the Y3Fe5O12 particles. The heat generation ability was slightly improved by the addition of SmFeO3 and the maximum value was 0.48 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) for n = 0.2 and 0.4 samples. The maximum heat generation ability was decreased for the excessive SmFeO3 mixed sample (n = 0.6). The calcination temperature for the formation of the ferrimagnetic material was increased by the SmFeO3 addition due to the depression of particle growth. (C)2014 The Ceramic Society of Japan. All rights reserved.
  • Naoki Wakiya, Junichi Takahashi, Hisao Suzuki, Taku Murase, Hiroshi Masumoto, Hiromichi Aono, Nobuyasu Adachi, Nobuhiro Matsushita, Naonori Sakamoto
    Journal of the Ceramic Society of Japan 122 (1421) P1  1348-6535 2014 [Peer-reviewed]
     Scientific journal
  • Hiromichi Aono, Ryota Senba, Tadahiko Nishimori, Takashi Naohara
    Journal of the American Ceramic Society 96 (11) 3483 - 3488 0002-7820 2013/11 [Peer-reviewed]
     Scientific journal 
    Y3Fe5O12 microspheres having a 20-32 μm diameter range were prepared by a spray dryer using a bead-milled nanosize powder. The high heat generation ability in an AC magnetic field was obtained by the bead milling of a commercial powder. The yield of the 20-32 μm microspheres was 13.5% after sifting using 20 and 32 μm sieves. The heat generation ability of the microsphere sample was almost the same as that for the bead-milled powder because the temperature enhancement mechanism was the Néel relaxation of the superparamagnetic material. Furthermore, the heat generation ability of the Y3Fe5O12 microsphere was improved by calcination at low temperature. The heat ability increased as a function proportional to the square of the increasing magnetic field for the noncalcined sample and the samples calcined at 600°C. For the samples calcined at 650°C or higher, the heat generation ability increased as a function proportional to the cube of the increasing magnetic field because of the particle growth to form single-domain ferrimagnetic particles. The sample calcined at 650°C showed the maximum heat generation ability(W/g) of 2.4·f·H3, where f and H are the frequency (kHz) and magnetic field (kA/m), respectively. © 2013 The American Ceramic Society.
  • Hiromichi Aono, Kazumasa Tamura, Erni Johan, Toru Yamamoto, Naoto Matsue, Teruo Henmi
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 96 (10) 3218 - 3222 0002-7820 2013/10 Scientific journal 
    The Na-P1-type zeolite having a high cation-exchange capacity (CEC) was obtained using the waste coal fly ash from thermal power stations and a 2M NaOH solution at 100 degrees C. The Na-P1-type zeolite was formed with the reaction time of 6h at 100 degrees C, and its CEC value increased with an increase in the reaction time. The addition of a suitable amount of NaAlO2 to the fly ash was also effective for improving the CEC value. A new composite material consisting of the Na-P1-type zeolite and magnetite was synthesized from the fly ash and iron chlorides because the magnetic collection was possible using this composite material after radioactive Cs+ ion adsorption. The existence of nanosized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by TEM observations. The CEC and magnetic property of these composite materials were characterized.
  • 壌からのCs 除染を目的とした磁化Na-P1 型ゼオライトの合成
    青野宏通, 横田彩子, 溝口裕己, 田村一将, 渡部祐輔, エルニ ジョハン, 山内理恵, 松枝直人, 山本 徹, 逸見彰男
    環境放射能除染学会誌 1 (1) 3 - 7 2013/08 [Peer-reviewed]
     Scientific journal
  • 磁化Na-P1型ゼオライトによる土壌Csの除去技術の開発
    逸見彰男, 青野宏通, 田村一将, 松枝直人, エルニ ジョハン, 山内理恵, 山本 徹, 福垣内 暁
    環境放射能除染学会誌 1 (1) 9 - 13 2013/08 [Peer-reviewed]
     Scientific journal
  • 人工ゼオライトを活用した研究開発テーマの発掘(第15章-第1節 )
    青野宏通, 逸見彰男
    技術シーズを活用した研究開発テーマの発掘, 技術情報協会 627 - 631 2013/07 [Peer-reviewed]
     Research society
  • 逸見 彰男, 青野 宏通, 田村 一将
    環境放射能除染学会誌 = Journal of the Society for Remediation of Radioactive Contamination in the Environment 環境放射能除染学会 1 (1) 9 - 13 2187-8382 2013/06
  • Hiromichi Aono, Kazumasa Tamura, Erni Johan, Rie Yamauchi, Toru Yamamoto, Naoto Matsue, Teruo Henmi
    CHEMISTRY LETTERS 42 (6) 589 - 591 0366-7022 2013/06 Scientific journal 
    For the decontamination of radioactive Cs-134 and Cs-137 using magnetic collection, a new composite material consisting of a Na-P1-type zeolite and magnetite was synthesized from the waste fly-ash from thermal power stations and iron chlorides. The presence of nanosized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by TEM observations. The cation-exchange capacity (CEC) and magnetic properties of these composite materials were characterized.
  • 放射性セシウムを吸着した後に磁場回収が可能なゼオライト-マグネタイト複合材料の開発
    青野 宏通
    月刊愛媛ジャーナル (5) 82 - 85 2013/05 [Invited]
     Research society
  • S. Yoshikawa, H. Hirazawa, H. Aono, T. Naohara, T. Maehara, Y. Watanabe
    Journal of the Magnetic Society of Japan 37 287 - 290 2013/04 [Peer-reviewed]
     International conference proceedings
  • S. Utsunomiya, H. Hirazawa, H. Aono, T. Naohara, T. Maehara, Y. Watanabe
    Journal of the Magnetic Society of Japan 37 291 - 294 2013/04 [Peer-reviewed]
     International conference proceedings
  • Takashi Naohara, Hiromichi Aono, Kentaro Shirai, Tsunehiro Maehara, Hideyuki Hirazawa, Shinya Matsutomo, Yuji Watanabe
    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 331 168 - 173 0304-8853 2013/04 Scientific journal 
    For application as a novel ablation therapy of human cancer, the heating property of a Ti-coated mild steel rod was studied in an AC magnetic field at 300 kHz. When the Ti-tube thickness was as low as 0.1 mm, the specimen, when placed parallel to the magnetic flux direction (theta=0 degrees), exhibited a significant increase in temperature; however, its value gradually decreased with the increasing Ti thickness. In computer simulation images, the high magnetic flux concentration and concurrent large current density were observed around the interface between the mild steel rod and the Ti-tube. The heating property was drastically different at the three inclination angles (theta=0 degrees, 45 degrees, and 90 degrees) to the magnetic flux direction. However, the effect of the inclination angle was markedly reduced in the mild steel rod surrounded by a 0.3 mm thick Ti-tube, suggesting that the non-oriented heating property will be achieved for the prototype ablation needle coated with a Ti layer having the optimum thickness. (c) 2012 Elsevier B.V. All rights reserved.
  • Takashi Naohara, Hiromichi Aono, Tsunehiro Maehara, Hideyuki Hirazawa, Shinya Matsutomo, Yuji Watanabe
    Journal of functional biomaterials 4 (1) 27 - 37 2013/02 [Peer-reviewed]
     Scientific journal 
    For the purpose of developing a novel ablation therapy for oral cancer, the heat generation and transfer properties of a Ti-coated carbon steel rod with 20-mm length and 1.8-mm outer diameter were investigated by means of a high-frequency induction technique at 300 kHz. The heat generation measurement performed using water (15 mL) revealed that the difference of the inclination angles (θ = 0°, 45° and 90°) relative to the magnetic flux direction only slightly affects the heating behavior, exhibiting the overlapped temperature curves during an induction time of 1200 s. These results suggest that the effect of the shape magnetic anisotropy is almost eliminated, being convenient for the precise control of the ablation temperature in clinical use. In the experiments utilizing a tissue-mimicking phantom, the heat transfer concentrically occurred in the lateral direction for both the planar surface and a 10-mm deep cross-section. However, the former exhibited a considerably lower increase in temperature (ΔT), probably due to the effect of heat dissipation to the ambient air. No significant heat transfer was found to occur to the lower side of the inserted Ti-coated carbon steel rod, which is situated in the longitudinal direction.
  • Depression of particle growth with calcination at low temperature and their heat generation property in AC magnetic field for the nano-sized magnetic Y3Fe5O12-nSmFeO3 powders prepared by bead-milling
    T. Nishimori, Y. Akiyama, T. Naohara, T. Maehara, H. Hirazawa, Y. Itagaki, H. Aono
    J. Ceram. Soc. Jpn. 121 13 - 16 2013 [Peer-reviewed]
  • Hiromichi Aono, Tomoya Kan, Yoshiteru Itagaki, Ken-Ichi Yamaguchi, Shun Itoh, Masato Kurihara, Masatomi Sakamoto
    Journal of the Ceramic Society of Japan 121 (1409) 21 - 25 1348-6535 2013 Scientific journal 
    A heteronuclear (NH4)2Sr[FeII(CN) 6] complex having a tetragonal phase was synthesized from Sr(NO 3)2 and (NH4)4[Fe II(CN)6]· nH2O. A single phase of the heteronuclear (NH4)2XLa1-XSr X[Fe(CN)6]·nH2O complex was synthesized by the coprecipitation for two heteronuclear hexacyano complexes of La[Fe III(CN)6]·5H2O and (NH4) 2Sr[FeII(CN)6]. In this chemical method, the X value (Sr content) for the complex was lower than that of the starting material. This (NH4)2XLa1-XSrX[Fe(CN) 6]·nH2O complex was also obtained by a mechanochemical reaction using a planetary ball-mill for two complexes (Total 0.01 mol = ca. 4g) of (1 - X)La-[FeIII(CN)6] ·5H2O and X(NH4)2Sr[Fe II(CN)6] with a small amount (5ml) of methanol. The hydration number calculated from the elemental analysis agreed with the estimated values when a hexagonal single (NH4)0.8La 0.6Sr0.4[Fe(CN)6]·4.2H2O phase formed for X = 0.4. This reaction for X = 0.4 was also possible for the dry process without methanol. In the case of X > 0.4, the peaks of the SrFe-complex were observed in the XRD pattern. The perovskite phase was directly formed by the thermal decomposition at a low temperature for the milled X = 0.4 complex. © 2013 The Ceramic Society of Japan.
  • Tadahiko Nishimori, Yusuke Akiyama, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Hiromichi Aono
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 121 (1409) 13 - 16 1882-0743 2013/01 Scientific journal 
    A superparamagnetic magnetic Y3Fe5O12 ferrite of 20.5 nm in particle size was prepared by bead milling using 0.05 mm phi beads for 10 h. The heat generation ability in an AC magnetic field (370 kHz, 1.77 kA-m(-1)) was 0.34 W.g(-1) for the bead-milled sample and was improved by calcination at low temperature. The main reason for this heat generation property of the milled samples was ascribed to a Neel relaxation of the superparamagnetic material. The maximum ability of 0.46 W.g(-1) in an AC magnetic field (370 kHz, 1.77 kA.m(-1)) was obtained for the sample (36.8 nm in particle size) calcined at 700 degrees C. The heat generation ability was decreased with particle growth when the calcination temperature was higher than 700 degrees C. For the sample calcined at 600 degrees C, the heat generation ability (W.g(-1)) was proportional to the square of the magnetic field (H/kA-m(-1)). In the case of the calcination at 700 degrees C, the heat generation ability (W.g(-1)) depended on the cube of the magnetic field. The heat generation mechanism would change from superparamagnetic to ferrimagnetic due to the pariticle growth at 700 degrees C. (C)2013 The Ceramic Society of Japan. All rights reserved.
  • Hiromichi Aono, Takaaki Nishida, Tomoya Kan, Yuu Jin-oka, Masato Kurihara, Masatomi Sakamoto, Yoshihiko Sadaoka
    MATERIALS LETTERS 83 151 - 153 0167-577X 2012/09 Scientific journal 
    A new heteronuclear (NH4)(2)Sr[Fe-II(CN)(6)] complex having a tetragonal phase was synthesized from Sr(NO3)(2) and (NH4)(4)[Fe-II(CN)(6)]center dot nH(2)O. A single phase of the heteronuclear (NH4)(2X)La1 - XSrX[Fe(CN)(6)]center dot nH(2)O complex was synthesized by the coprecipitation of two heteronuclear hexacyano complexes of La[Fe-III(CN)(6)]center dot 5H(2)O and (NH4)(2)Sr[Fe-II(CN)(6)]. The X value (Sr content) for the complex was lower than that of the starting material. The perovskite-type La1 - XSrXFeO3 (-) (alpha) phase was directly formed by the thermal decomposition even at 250 degrees C for 1 h. (C) 2012 Elsevier B.V. All rights reserved.
  • Hiromichi Aono, Hiroki Ebara, Ryota Senba, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yuji Watanabe
    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 324 (12) 1985 - 1991 0304-8853 2012/06 Scientific journal 
    Nano-sized magnetic Y3Fe5O12 ferrite having a high heat generation ability in an AC magnetic field was prepared by bead milling. A commercial powder sample (non-milled sample) of ca. 2.9 mu m in particle size did not show any temperature enhancement in the AC magnetic field. The heat generation ability in the AC magnetic field improved with a decrease in the average crystallite size for the bead-milled Y3Fe5O12 ferrites. The highest heat ability in the AC magnetic field was for the fine Y3Fe5O12 powder with a 15-nm crystallite size (the samples were milled for 4 h using 0.1 mm phi beads). The heat generation ability of the excessively milled Y3Fe5O12 samples decreased. The main reason for the high heat generation property of the milled samples was ascribed to an increase in the Neel relaxation of the superparamagnetic material. The heat generation ability was not influenced by the concentration of the ferrite powder. For the samples milled for 4 h using 0.1 mm phi beads, the heat generation ability (W g(-1)) was estimated using a 3.58 x 10(-4) fH(2) frequency (f/kHz) and the magnetic field (H/kA m(-1)), which is the highest reported value of superparamagnetic materials. (C) 2012 Elsevier B.V. All rights reserved.
  • Hiromichi Aono, Takaaki Nishida, Masato Kurihara, Masatomi Sakamoto, Yoshihiko Sadaoka
    CERAMICS INTERNATIONAL 38 (3) 2333 - 2338 0272-8842 2012/04 Scientific journal 
    New heteronuclear (NH4)REIII[Fe-II(CN)(6)]center dot nH(2)O complexes (RE = La, Ce, Pr, Nd, Sm, Gd, Dy, Y, Er, Lu) were synthesized and their thermal decomposition products were investigated. The crystal structure of (NH4)RE[Fe-II(CN)(6)]center dot nH(2)O would be a hexagonal unit cell (space group: P6(3)/m), which was the same as that of La[Fe-II(CN)(6)]center dot 5H(2)O. The hydration number n = 4 was estimated by TG results for all the RE complexes. The lattice constants depended on the ionic radius of the RE3+ ion for the heteronuclear complexes. The single phase of the perovskite type materials was directly obtained by decomposition of the heteronuclear complexes for RE = La, Pr, Nd, Sm, and Gd. A mixture of CeO2 and Fe2O3 was formed for RE = Ce because of its oxidation to Ce4+. In the case of RE = Dy, Y, Er, and Lu complexes, the perovskite type materials formed at higher temperature via, mixed oxides such as RE2O3 and RE4Fe5O13 due to the small RE3+ ionic radius. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
  • Takashi Naohara, Hiromichi Aono, Tsunehiro Maehara, Hideyuki Hirazawa, Shinya Matsutomo, Yuji Watanabe
    Journal of functional biomaterials 3 (1) 163 - 72 2012/03 [Peer-reviewed]
     Scientific journal 
    To develop a novel ablation therapy for human solid cancer, the heating properties of a ferromagnetic carbon steel rod and a prototype Ti-coated needle using this carbon steel rod, were investigated in several high-frequency outputs at 300 kHz. In the former, the heating property was drastically different among the three inclination angles (θ = 0°, 45° and 90°) relative to the magnetic flux direction as a result of the shape magnetic anisotropy. However, the effect of the inclination angles was completely eliminated in the latter. It is considered that the complete non-oriented heating property relative to the magnetic flux direction allows the precise control of the ablation temperature during minimally invasive thermotherapy without a lead-wire connected to a fiber-optic thermometer. This newly designed Ti-coated device will be suitable for clinical use combined with its superior biocompatibility for ablation treatments using high-frequency induction heating.
  • 猶原隆, 青野宏通, 中住慎一
    愛媛大学社会連携推進機構研究成果報告書 (5) 8 - 10 2012/03 Research institution
  • Motohira Yoshida, Mitsunori Sato, Yuji Yamamoto, Tsunehiro Maehara, Takashi Naohara, Hiromichi Aono, Hiroki Sugishita, Koichi Sato, Yuji Watanabe
    JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY 27 (2) 406 - 411 0815-9319 2012/02 [Peer-reviewed]
     Scientific journal 
    Background and Aim: We have studied and reported the usefulness of tumor local chemohyperthermia at a low-grade temperature below 43 degrees C with docetaxel-embedded magnetoliposome (DML) and an applied alternating current magnetic field. However, the mechanisms of this treatment and the dynamics of the injected docetaxel were not investigated in our previous study. Thus, we investigated the interaction of chemotherapy and hyperthermia in the treated tumor. Methods: Human MKN45 gastric cancer cells were implanted in the hind limbs of Balb-c/ nu/ nu mice. DML, magnetite-loaded liposome, and docetaxel were injected into the tumors with or without being exposed to an alternating current magnetic field. Docetaxel and tumor necrosis factor-a concentrations, the cell cycle, and cell death rates in the tumor were examined. Results: Docetaxel concentrations were significantly higher in the DML-injected group than in the docetaxel-injected group 3 days after injection. A G2/ M peak was observed 1 day after treatment in the DML-injected and exposed group and the docetaxel-injected group, while it was observed 3 days after treatment in the DML-injected without heating group and the magnetite-loaded liposome group. The tumor cell death rate gradually increased in the DML-injected group, with or without being exposed, while it gradually decreased after its peak in other groups. The tumor necrosis factor-a concentration in the tumor treated with DML with heating remained at a high level on the 7th day after treatment, while it decreased after its peak in other groups. Conclusion: The antitumor effect of this treatment derives from a combination of hyperthermia and chemotherapy locally in the tumor.
  • Improvement of Heat Generation Ability in AC magnetic field and Magnetic Properties for Spinel Type MgFe2O4 ferrite by Cu Substitution and Beads Milling
    H. Hirazawa, H. Aono, T. Naohara, T. Maehara, Y. Watanabe
    J. Iron Steel Res, Inter. 19 596 - 599 2012 [Peer-reviewed]
  • Hiromichi Aono, Hiroki Ebara, Ryota Senba, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yuji Watanabe
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 94 (12) 4116 - 4119 0002-7820 2011/12 Scientific journal 
    We found that the nano-sized Y3Fe5O12 powder prepared by bead milling has the highest heat generation ability in an AC magnetic field of reported superparamagnetic materials. The heat generation ability in an AC magnetic field was strongly improved by a decrease in the average crystallite size of the bead milled samples. The highest heat ability in the AC magnetic field was for the fine Y3Fe5O12 powder with ca. 15nm crystallite size (the samples milled for 4 h using 0.1 mm beads). The reasons for the high heat generation properties of the milled samples are ascribed to an increase in the Neel relaxation of the superparamagnetic material. The heat generation ability (W.g(-1)) can be estimated using a 3.58 x 10(-4)f.H-2 frequency (f/kHz) and the magnetic field (H/kA.m(-1)) for the sample milled for 4 h using 0.1mm phi beads.
  • Hiromichi Aono, Jun Izumi, Musashi Tomida, Yoshihiko Sadaoka
    MATERIALS CHEMISTRY AND PHYSICS 130 (3) 973 - 979 0254-0584 2011/11 Scientific journal 
    For the preparation of precursors for fine perovskite-type (0.05 mol) materials, the metal nitrates were completely dissolved in a water solution (total 100 ml) with organic solvent of ethylene glycol (EG), diethylene glycol (DEG), or glycerin (GL), and then dried at 120 degrees C. In the case of a La-Fe precursor without organic solvent, LaFeO(3) was not the main phase for the calcined materials even at 1000 degrees C. However, the LaFeO(3) single phase was obtained by mixing a small amount of organic solvent EG (>= 10 ml), DEG(>= 5 ml), and GL(>= 5 ml) into the solution. In the case of EG, clear XRD peaks of the LaFeO(3) single phase were obtained by calcination even at 350 degrees C. A higher calcination temperature for the formation of the LaFeO(3) phase was needed with an increase in the amount of the mixed organic solvent. The oxygen in these organic molecules would act to coordinate to the metal ions instead of nitric acid ions to form a quasipolymer containing metal ions in a random position, because the nitrogen elemental ratio in the precursor decreased with the amount of added organic solvent. The elemental distribution of La and Fe was highly homogeneous for the decomposed sample. The La(1-x)Sr(x)MnO(3) system was also examined by this method using GL. A single perovskite-type phase formed even for calcination at 700 degrees C. (C) 2011 Elsevier B.V. All rights reserved.
  • Hiromichi Aono, Yusuke Watanabe, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yuji Watanabe
    MATERIALS CHEMISTRY AND PHYSICS 129 (3) 1081 - 1088 0254-0584 2011/10 Scientific journal 
    Nano-sized FeFe2O4 ferrite powder having a heat generation ability in an AC magnetic field was prepared by bead milling for a thermal coagulation therapy application. A commercial powder sample (non-milled sample) of ca. 2.0 mu m in particle size showed a temperature enhancement (Delta T) of 3 degrees C in an AC magnetic field (powder weight 1.0g, 370 kHz, 1.77 kA m(-1)) in ambient air. The heat generation ability in the AC magnetic field improved with the milling time, i.e., due to a decrease in the average crystallite size for all the examined ferrites. The highest heat ability (Delta T = 26 degrees C) in the AC magnetic field in ambient air was for the fine FeFe2O4 powder with a 4.7 nm crystallite size (the samples were milled for 6 h using 0.1 mm phi beads). However, the heat generation ability decreased for the excessively milled FeFe2O4 samples having average crystallite sizes of less than ca. 4.0 nm. The heat generation of the samples showed some dependence on the hysteresis loss for the B-H magnetic property. The reasons for the high heat generation properties of the milled samples would be ascribed to an increase in the Neel relaxation of the superparamagnetic material. The hysteresis loss in the B-H magnetic curve would be generated as the magnetic moment rotates (Neel relaxation) within the crystal. The heat generation ability (Wg(-1)) can be estimated using a 1.07 x 10(-4) fH(2) frequency (f, kHz) and the magnetic field (H, kA m(-1)) for the samples milled for 6 h using 0.1 mm phi beads. Moreover, an improvement in the heating ability was obtained by calcination of the bead-milled sample at low temperature. The maximum heat generation (Delta T = 59 degrees C) ability in the AC magnetic field in ambient air was obtained at ca. 5.6 nm for the sample calcined at 500 degrees C. The heat generation ability (Wg(-1)) for this heat treated sample was 2.54 x 10(-4) fH(2). (C) 2011 Elsevier B.V. All rights reserved.
  • Hiromichi Aono, Kenji Moritani, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yuji Watanabe
    MATERIALS LETTERS 65 (10) 1454 - 1456 0167-577X 2011/05 Scientific journal 
    We found the most promising powder material for the application of the thermal coagulation therapy for the treatment of cancerous tissues. The maximum heat generation ability (Delta T = 40-77 degrees C, 370 kHz, 1.77 kA.m(-1)) was obtained for the powder materials by the calcination at 1100 degrees C for the Y3 - XGdXFe5O12 system. This Delta T value is higher than ca. Delta T = 30 degrees C in same magnetic field for fine FeFe2O4 particles as the candidate material for this type of therapy. The particle growth with the formation of the cubic single phase might influence to the high heat generation. As an unexpected result, the Gd3Fe5O12 (X=3) has no heat generation ability in an AC magnetic field. (C) 2011 Elsevier B.V. All rights reserved.
  • Akihiro Inukai, Naonori Sakamoto, Hiromichi Aono, Osamu Sakurai, Kazuo Shinozaki, Hisao Suzuki, Naoki Wakiya
    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 323 (7) 965 - 969 0304-8853 2011/04 Scientific journal 
    Biocompatible hybrid particles composed of hydroxyapatite (Ca-10(PO4)(6)(OH)(2), HAp) and ferrite (gamma-Fe2O3 and Fe3O4) were synthesized using a two-step procedure. First, the ferrite particles were synthesized by co-precipitation. Second, the suspension, which was composed of ferrite particles by a co-precipitation method, Ca(NO3)2, and H3PO4 aqueous solution with surfactant, was nebulized into mist ultrasonically. Then the mist was pyrolyzed at 1000 degrees C to synthesize HAp-ferrite hybrid particles. The molar ratio of Fe ion and HAp was (Fe2+ and Fe3+)/HAp=6. The synthesized hybrid particle was round and dimpled, and the average diameter of a secondary particle was 740 nm. The cross section of the synthesized hybrid particles revealed two phases: HAp and ferrite. The ferrite was coated with HAp. The synthesized hybrid particles show a saturation magnetization of 11.8 emu/g. The net saturation magnetization of the ferrite component was calculated as 32.5 emu/g. The temperature increase in the AC-magnetic field (370 kHz, 1.77 kA/m) was 9 degrees C with 3.4 g (the ferrite component was 1.0 g). These results show that synthesized hybrid particles are biocompatible and might be useful for magnetic transport and hyperthermia studies. (C) 2010 Elsevier B.V. All rights reserved.
  • Hideyuki Hirazawa, Hiromichi Aono, Takashi Naohara, Tsunehiro Maehara, Mitsunori Sato, Yuji Watanabe
    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 323 (6) 675 - 680 0304-8853 2011/03 Scientific journal 
    Nanosized MgFe2O4-based ferrite powder having heat generation ability in an AC magnetic field was prepared by bead milling and studied for thermal coagulation therapy applications. The crystal size and the particle size significantly decreased by bead milling. The heat generation ability in an AC magnetic field improved with the milling time, i.e. a decrease in crystal size. However, the heat generation ability decreased for excessively milled samples with crystal sizes of less than 5.5nm. The highest heat ability (Delta T34 degrees C) in the AC magnetic field (370kHz, 1.77kA/m) was obtained for fine MgFe2O4 powder having a ca. 6 nm crystalsize (the samples were milled for 6-8 h using 0.1 mm phi beads). The heat generation of the samples was closely related to hysteresis loss, a B-H magnetic property. The reason for the high heat generation properties of the samples milled for 6-8 h using 0.1 mm f beads was ascribed to the increase in hysteresis loss by the formation of a single domain. Moreover, the improvement in heating ability was obtained by calcination of the bead-milled sample at low temperature. In this case, the maximum heat generation (Delta=41 degrees C) ability was obtained for a ca. 11 nm crystal size sample was prepared by crystal growth during the sample calcination. On the other hand, the Delta T value for Mg0.5Ca0.5Fe2O4 was synthesized using a reverse precipitation method decreased by bead milling. (C) 2010 Elsevier B.V. All rights reserved.
  • H. Hirazawa, H. Aono, K. Moritani, T. Naohara, T. Maehara, Y. Watanabe
    3RD INTERNATIONAL CONGRESS ON CERAMICS (ICC3): ADVANCES IN ELECTRO CERAMICS 18 1757-8981 2011 International conference proceedings 
    The Y3Fe5O12-based ferrite, i.e., Y3-XGdXFe5O12 system was synthesized using a reverse coprecipitation method for application of new thermal coagulation therapy using an AC magnetic field for the treatment of cancerous tissues. The mixed phase of the Y3Fe5O12-type orthorhombic and cubic materials without any impurities were obtained for this systems calcined at low temperature in XRD results. However the orthorhombic phase almost disappeared by the calcination at 1150 degrees C or higher temperature for all the X samples. The calcination temperature strongly influenced the heat generation ability. The maximum heat generation ability (Delta T= 40-63 degrees C, 370kHz, 1.77kA/m) was obtained for the powder materials sintered at 1100 degrees C for the Y3-XGdXFe5O12 system. The particle growth with the formation of the cubic single phase strongly influenced to the heat generation.
  • Takashi Naohara, Hiromichi Aono, Hideyuki Hirazawa, Tsunehiro Maehara, Yuji Watanabe, Shinya Matsutomo
    COMPEL-THE INTERNATIONAL JOURNAL FOR COMPUTATION AND MATHEMATICS IN ELECTRICAL AND ELECTRONIC ENGINEERING 30 (5) 1582 - 1588 0332-1649 2011 Scientific journal 
    Purpose - The purpose of this paper is to develop a ferromagnetic needle adaptable for a novel ablation cancer therapy; the heat generation ability of the mild steel rod embedded into the Ti-tube having a different thickness was investigated in a high-frequency output at 300 kHz.Design/methodology/approach - The outer diameter and length of the Ti-tubes were 1.8 and 20 mm, respectively, while the inner diameter was varied from 1.6 to 0 mm. The mild steel rod was embedded in a Ti-tube for preparing the needle-type specimen. Their heat generation ability was examined by changing the inclination angle to the magnetic flux direction in a high-frequency coil.Findings - When the thickness of the Ti surrounding the mild steel rod was as low as 0.1 mm, the heat generation ability was drastically different among the three inclination angles (theta = 0 degrees, 45 degrees, and 90) to the magnetic flux direction due to the effect of the shape-induced magnetic anisotropy. However, the effect of the inclination angle was almost eliminated in the specimen surrounded by the 0.4 mm thick Ti, suggesting that the non-oriented heat generation property is achieved for the needle-type mild steel rod coated with Ti having the optimum thickness.Originality/value - The prototype ablation needle having a complete non-oriented heat generation ability was fabricated to use in subsequent animal experiments. It is considered that the newly designed Ti-coated device is useful in ablation treatments using a high-frequency induction heating.
  • Hiromichi Aono, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Shinya Matsutomo, Yuji Watanabe
    Journal of Magnetism and Magnetic Materials 323 (1) 88 - 93 0304-8853 2011/01 Scientific journal 
    The heat generation ability of needle-type materials was studied for the application of thermal coagulation therapy in an AC magnetic field. Although the Ti tube without the MgFe2O4 powder or Ti rod showed poor heat generation abilities in an AC magnetic field, the temperature was significantly increased by the presence of ferrite powder in the Ti tube. We confirmed using a computer simulation that the eddy loss of the Ti tube was increased by the enhanced magnetic flux density due to the ferrite powder in the Ti tube. The heat generation of the ferrite filled Ti tube was increased by utilization of the quenched MgFe2O4 powder from elevated temperature. The relative magnetic permeability of the quenched ferrite was enhanced with the decrease in the inverse ratio of the cubic spinel structure. The heat generation ability was increased with the increase in the relative magnetic permeability of the Ti tube with ferrite powder. The calculated joule loss based on the experimental results showed an agreement with those using the computer simulation. © 2010 Elsevier B.V. All rights reserved.
  • Hiromichi Aono, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yuji Watanabe
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 118 (1384) 1207 - 1211 1882-0743 2010/12 Scientific journal 
    MgFe2O4 microspheres having a 20-32 mu m diameter range were prepared by a spray dryer using bead-milled nano-sized particles. A commercial powder having a several mu m particle size was bead-milled to an approximate 6.2 nm crystallite size. The microspheres were obtained using the spray dryer when the air pressure was low (0.03 MPa). The yield of the MgFe2O4 20-32 mu m microspheres was improved by combination of a low air pressure and high ferrite concentration in the slurry. The heat generation ability in an AC magnetic field (370 kHz, 1.77 kA/m) was improved by the bead milling. (C) 2010 The Ceramic Society of Japan. All rights reserved.
  • Keiko Sato, Shun Itoh, Ken-ichi Yamaguchi, Masato Kurihara, Masatomi Sakamoto, Hiromichi Aono, Yoshihiko Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 118 (1377) 384 - 386 1882-0743 2010/05 Scientific journal 
    Thermal decomposition of the coordination polymer, (NH4)La[Fe-II(CN)(6)]center dot 4.5H(2)O, with a three-dimensional network structure formed by the Fe-II-CN-La-III linkages, was investigated. The decomposition began at around 323 K and proceeded via a few steps to give the anhydride complex, (NH4)La[Fe-II(CN)(6)], at around 523 K. Further heating gave rise to an abrupt collapse of cyanide groups at around 573 K, followed by the initial formation of the perovskite-type oxide, LaFeO3, at 603 K and the completion of the decomposition to produce LaFeO3 at around 898 K. Any formation of the component metal oxides, La2O3 and Fe2O3, was not recognized during the decomposition. From the XRD line broadening using Scherrer's equation, the average size of the thermal decomposition product was evaluated to be 21, 22, 25 and 30 nm at 773, 823, 898 and 1073 K, respectively. The specific surface area of the LaFeO3 particles prepared at 898, 1073 and 1273 K was 13.2, 8.6 and 2.5 m(2) g(-1), respectively. (C) 2010 The Ceramic Society of Japan. All rights reserved
  • Motohira Yoshida, Yuji Watanabe, Mitsunori Sato, Tsunehiro Maehara, Hiromichi Aono, Takashi Naohara, Hideyuki Hirazawa, Atsushi Horiuchi, Shungo Yukumi, Koichi Sato, Hiromichi Nakagawa, Yuji Yamamoto, Hiroki Sugishita, Kanji Kawachi
    International journal of cancer 126 (8) 1955 - 1965 0020-7136 2010/04 [Peer-reviewed]
     
    Hyperthermia is a minimally invasive approach to cancer treatment, but it is difficult to heat only the tumor without damaging surrounding tissue. To solve this problem, we studied the effectiveness of chemohyperthermia with docetaxel-embedded magnetoliposomes (DMLs) and an applied alternating current (AC) magnetic field. Human MKN45 gastric cancer cells were implanted in the hind limb of Balb-c/nu/nu mice. Various concentrations of docetaxel-embedded DMLs were injected into the tumors and exposed to an AC magnetic field (n = 6, each). For comparison with hyperthermia alone, magnetite-loaded liposome (ML)-injected tumors were exposed to an AC magnetic field. Furthermore, the results of DML without AC treatment and docetaxel diluted into PBS with AC treatment were also compared (n = 10, each). Tumor surface temperature was maintained between 42 and 43 degrees C. Tumor volume was reduced in the DML group with a docetaxel concentration > 56.8 microg/ml, while a docetaxel concentration > 568.5 microg/ml was required for tumor reduction without hyperthermia. Statistically significant differences in tumor volume and survival rate were observed between the DML group exposed to the magnetic field and the other groups. The tumor disappeared in 3 mice in the DML group exposed to the magnetic field; 2 mice survived over 6 months after treatment, whereas all mice of the other groups died by 15 weeks. Histologically, hyperthermia with DML damaged tumor cells and DML diffused homogeneously. To the best of our knowledge, this is the first report to show that hyperthermia using chemotherapeutic agent-embedded magnetoliposomes has an anticancer effect.
  • Heat Generation Ability in AC Magnetic Field of Nano Sized Ferrite Powder Prepared by Physical Bead Milling for Thermal Coagulation Therapy
    Proc. of International Symposium on Heating by Electromagnetic Sources 483 - 489 2010
  • Heat generation ability in AC magnetic field of needle-type Ti-coated mild steel for ablation cancer therapy
    Proc. of International Symposium on Heating by Electromagnetic Sources 507 - 511 2010
  • Hiromichi Aono, Musashi Tomida, Yoshihiko Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 117 (1369) 1048 - 1051 1882-0743 2009/09 Scientific journal 
    The metal nitrates were completely dissolved in a mixed solvent (total 100 nil) of ethylene glycol (EG) (0, 5, 10, 15, 25, and 50 ml) and water, and then dried at 120 degrees C to make precursors for the fine LaFeO3 (0.05 mol) material. The main product was not LaFeO3 for the precursor prepared using the nitrate solution containing a small amount of EG (less than 5 ml). The mixed solution of the 10-15 ml EG with water was suitable for the preparation of 0.05 mol LaFeO3. In this case, clear XRD peaks of LaFeO3 single phase were obtained by the calcination even at 350 degrees C using this method. The higher calcination temperature for the formation of the LaFeO3 phase was needed due to the increased EG amount in the solvent. The particle size was ca. 40 nm for the (EG 10 ml) samples calcined at 350-600 degrees C and it increased with an increase in the calcining temperature. (C) 2009 The Ceramic Society of Japan. All rights reserved.
  • Naoki Takeda, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 117 (1362) 175 - 178 1882-0743 2009/02 Scientific journal 
    The reactivity of a newly developed oxygen ionic conductor, Nd-9.83(SiO4)(4.5)(AlO4)(1.5)O-2, with alkali carbonates was examined in air and CO2. The reactivity of the developed ionic conductor was substantially lower than that of ZrO2, 3YSZ and 8YSZ in air and also in CO2. It is concluded that this newly developed oxide is more tolerant to the alkali contamination and is applicable as a potentiometric oxygen concentration gas sensor. (C) 2009 The Ceramic society of Japan, All rights reserved.
  • Effect of crystal sizes on heat generation ability in AC magnetic field for FeFe2O4 ferrite powder prepared by bead milling
    Proc. of 26th International Japan-Korea Seminar on Ceramics 760 - 763 2009
  • Preparation of fine ferrite powder using bead mill and its heat generation ability in AC magnetic field
    Proc. of 6th International Conference on Electromagnetic Processing of Materials (EPM2009) 189 - 192 2009
  • High Heat Generation Ability under AC Magnetic Field for Y3Fe5O12 Prepeared by Reverse Coprecipitation Method
    Proc. of 6th International Conference on Electromagnetic Processing of Materials (EPM2009) 185 - 188 2009
  • Computer simulation of heat generation ability in AC magnetic field for needle-type materials
    Proc. of 6th International Conference on Electromagnetic Processing of Materials (EPM2009) 193 - 196 2009
  • 金属材料の交流磁場中での発熱とシミュレーション
    工学ジャーナル 8 54 - 58 2009
  • Shungo Yukumi, Yuji Watanabe, Atsushi Horiuchi, Takashi Doi, Kohichi Sato, Motohira Yoshida, Yuji Yamamoto, Tsunehiro Maehara, Hiromichi Aono, Takashi Naohara, Kanji Kawachi
    INTERNATIONAL JOURNAL OF HYPERTHERMIA 25 (6) 416 - 421 0265-6736 2009 [Peer-reviewed]
     Scientific journal 
    Purpose: This study investigated the efficacy of repeated thermotherapy for breast cancer utilising a novel sintered MgFe2O4 needle and alternating current (AC) magnetic field in xenograft animal models mimicking human breast cancer. Materials and methods: A sintered MgFe2O4 needle and an apparatus to apply an AC magnetic field were prepared for this study. Animals bearing BT-474 tumours (mean (+/- standard deviation) volume, 471 +/- 153 mm(3)) were divided into four groups. A sintered MgFe2O4 needle (length, 5 mm) was placed in the centre of each tumour. An AC magnetic field (amplitude, 4 kA/m; 2 kW; 540 kHz) was applied for 10 min once, twice or three times for the first, second and third groups, respectively, and was not applied for the control group. Temperature during treatment and tumour volume 8 weeks after first treatment were assessed. Results: Maximum tumour temperature tended to increase in repeated-application groups: group 1, 59.2 +/- 4 degrees C; group 2, 58.9 +/- 3.3 degrees C and 61.2 +/- 8.9 degrees C for the first and second applications; and group 3, 60.4 +/- 4.6 degrees C, 62.1 +/- 7.8 degrees C and 71.1 +/- 6.1 degrees C for the first, second and third applications. Tumour volumes in control, groups 1, 2 and 3 at 8 weeks after treatment were 3633 +/- 2478 mm(3), 3240 +/- 1031 mm(3), 1252 +/- 1289 mm(3) and 0 mm(3), respectively. Tumours were significantly smaller in group 3 than in the control and group 1 at 8 weeks. Conclusions: The efficacy of repeated inductive heating utilising a sintered MgFe2O4 needle was demonstrated. Thermotherapy using the present method may offer an effective non-surgical treatment for human breast cancer.
  • Yuji Watanabe, Koichi Sato, Shungo Yukumi, Motohira Yoshida, Yuji Yamamoto, Takashi Doi, Hiroki Sugishita, Takashi Naohara, Tsunehiro Maehara, Hiromichi Aono, Kanji Kawachi
    BIO-MEDICAL MATERIALS AND ENGINEERING 19 (2-3) 101 - 110 0959-2989 2009 [Peer-reviewed]
     Scientific journal 
    Magnetic metal particles are known to induce heat energy under an alternating magnetic field (AMF). We developed a local tumor-heating device incorporating an MgFe2O4 needle for the purpose of mild ablation for cancer treatment. A needle made from sintered MgFe2O4 particles was embedded in the hepatic or breast tumors. Tumors were then heated by the energy dissipated from the needle exposed to an AMF. We sequentially evaluated histological changes, cellular activity of tumors, and the extent of thermal effect using nicotinamide adenine dinucleotide (NADH) diaphorase and terminal deoxynucleotidyl tranferase-mediated digoxigenin-DUTP nick-end labeling (TUNEL) staining. The mean temperature of the tumor tissue during heating was about 60 degrees C. Nuclei of the tumor cells became hyper-chromatin immediately after heating. The injured area spread progressively until 3 days after heating; when the area was surrounded by fibroblasts (meaning is not clear). Tumors disappeared after treatment without complications. This is the first time that the complete death of tumor cells has been realized by raising the tumor temperature above 60 degrees C using the heat generated by magnetic metal particles exposed to AMF. This device may be useful in the future for local hyperthemic treatment of human cancers.
  • AONO Hiromichi, NAOHARA Takashi, NAOHARA Takashi, MAEHARA Tsunehiro, SATO Mitsunori, WATANABE Yuji
    Materials science and technology 日本材料科学会 45 (No.6) 26 - 31 1347-4774 2008/12
  • Hiromichi Aono, Kengo Nishimura, Naoko Yamamoto, Yoshiteru Itagaki, Yoshihiko Sadaoka
    SENSOR LETTERS 6 (6) 979 - 982 1546-198X 2008/12 [Peer-reviewed]
     Scientific journal 
    Highly dense NASICON (Na1+xZr2SixP3-xO12, x = 2 and 3) electrolytes were synthesized using a sol-gel method for application in a CO2 as sensor. The conductivity decreased by increasing the x value from 2 and 3. The x = 2 material is reactive to alkali carbonate (M2CO3, M = Li and Na) at 600 degrees C by forming the alkali rich NASICON. In the case of x = 3, the NASICON phase in the mixture with Li carbonate and Na carbonate is stable even at 700 degrees C, since all the alkali ion sites in the NASICON are filled by Na+ ions for x = 3. We confirmed that the EMF drift for the CO2 gas sensor using the x = 3 electrolyte is lower than that using the x = 2 electrolyte.
  • Hideyuki Hirazawa, Satoshi Kusamoto, Hiromichi Aono, Takashi Naohara, Kensaku Mori, Yasumasa Hattori, Tsunehiro Maehara, Yuji Watanabe
    JOURNAL OF ALLOYS AND COMPOUNDS 461 (1-2) 467 - 473 0925-8388 2008/08 [Peer-reviewed]
     Scientific journal 
    New magnetic materials having a potentially high heat generation ability in an ac magnetic field were studied for application in thermal coagulation therapy. The Mg1-xCaxFe2O4 ferrites with X varied from 0 to 1.0 were synthesized using a reverse coprecipitation method. The obtained precursors were calcined at various temperatures in the range of 300-1000 degrees C with the intent to obtain fine ferrite powders. The heat generation in an ac magnetic field was very poor for X = 0. However, the heat generation improved with partial Ca2+ substitution of the Mg2+ sites. The maximum rise in temperature (Delta T) in the ac magnetic field (370kHz, 1.77 kA/m) was ca. 50 degrees C for the samples with 1.0g in weight and 0.2-0.8 in X of Mg1-xCaxFe2O4. Especially, the samples calcined at 800 degrees C showed the highest heat generation. When the Ca2+-substituted samples were calcined at 900 degrees C, the heat generation was reduced due to decomposition into the two phases of the MgFe2O4-type cubic and CaFe2O4-type orthorhombic. In addition, the samples calcined at 300 degrees C also showed a high heat generation. Although the crystal and particle sizes increased with the calcination temperature, they did not influence the heat generation of this system. The heat generation of the samples was closely related to the hysteresis loss. The reason for the high heat generation properties of the samples calcined at 300 and 800 degrees C is ascribed to the increase in the hysteresis loss by distortion of the cubic crystal structure. (c) 2007 Elsevier B.V All rights reserved.
  • 固体電解質を用いた炭酸ガスセンサの安定化
    青野宏通, 定岡芳彦
    マテリアル インテグレーション 5 70 - 75 2008/05 [Invited]
     Research society
  • 青野 宏通, 定岡 芳彦
    マテリアルインテグレーション ティー・アイ・シィー 21 (5) 70 - 75 1344-7858 2008/05
  • Hiromichi Aono, Hideyuki Hirazawa, Takashi Naohara, Tsunehiro Maehara
    Applied Surface Science 254 (8) 2319 - 2324 0169-4332 2008/02 [Peer-reviewed]
     Scientific journal 
    To study surface behaviors, MgFe2O4 ferrite materials having different grain sizes were synthesized by two different chemical methods, i.e., a polymerization method and a reverse coprecipitation method. The single phase of the cubic MgFe2O4 was confirmed by the X-ray diffraction method for both the precursors decomposed at 600-1000 °C except for a very small peak of Fe2O3 was detected for the samples calcined at 600 and 700 °C by the polymerization method. The crystal size and particle size increased with an increase in the sintering temperature using both methods. The conductance of the MgFe2O4 decreased when the atmosphere was changed from ambient air to air containing 10.0 ppm NO2. The conductance change, C = G(air)/G(10 ppm NO2), was reduced with an increase in the operating temperature. For the polymerization method, the maximum C-value was ca. 40 at 300 °C for the samples sintered at 900 °C. However, the samples sintered at 1000 °C showed a low conductance change in the 10 ppm NO2 gas, because the ratio of the O2 gas adsorption sites on the particle surface is smaller than those of the samples having a high C-value. The low Mg content on the surface affects the low ratio of the gas adsorption sites. For the reverse coprecipitation method, the particle size was smaller than that of the polymerization method. Although a stable conductance was obtained for the sample sintered at 900 and 1000 °C, its conductance change was less than that of the polymerization method. © 2007 Elsevier B.V. All rights reserved.
  • Mitsuru Yamauchi, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 28 (1) 27 - 34 0955-2219 2008 [Peer-reviewed]
     Scientific journal 
    The thermal stability of a mixture of Li2CO3 and rare earth oxide (R2O3) was examined under a dry condition. The heat-treatment of the mixture in CO2 ambience resulted in the formation of rare earth carbonates for R = La, Pr, Nd, Sm, Eu, and Gd except for Ho-Lu and Y. Lithiation of their rare earth dioxymonocarbonate, i.e., R2O2+2x(CO3)(1-x)Li-2x was confirmed for R = La, Pr, Nd, and Sm when the mixture was heated at 900 degrees C. The lithiation degree, x, was increased with an increase in the heat-treatment temperature in CO2 and was lower than 0.3. The stability of lithium rare earth dioxymonocarbonate decreased with the atomic number of the rare earth. The high reactivity of the light rare earth oxides with Li2CO3 would be attributed to that the large R3+-O2- distance for CN = 5 and 6 with an increase in the ionic [R3+]/[O2-] ratio for the rare earth oxides and is very similar with that of the rare earth dioxymonocarbonates. (c) 2007 Elsevier Ltd. All rights reserved.
  • Shungo Yukumi, Yuji Watanabe, Atsushi Horiuchi, Takashi Doi, Kohichi Sato, Motohira Yoshida, Tsunehiro Maehara, Hiromichi Aono, Takashi Naohara, Kanji Kawachi
    ANTICANCER RESEARCH 28 (1A) 69 - 74 0250-7005 2008/01 [Peer-reviewed]
     Scientific journal 
    Background: This study investigated a novel approach for tumor ablation therapy using an alternating magnetic field combined with a sintered MgFe(2)O(4) needle. This method differs from radiofrequency ablation (RFA) by dielectric heating with regard to the heating mechanism and improves some weak points of these conventional thermotherapies. Materials and Methods: Nude mice mimicking human breast cancer BT474 were treated using this method. The extent of tumor death was assessed after ablation. Results: Staining with hematoxylin and eosin showed gradual expansion of the pyknotic area until 48 h after ablation. Nicotinamide adenine dinucleotide diaphorase staining also showed complete tumor death by 48 h after treatment. The ablation area was well controlled and reablation was not necessary. The tumor could be completely controlled using this method without any risk of skin burn. Conclusion: This novel ablation therapy appeared to be more effective and less invasive for treatment of breast cancer treatment than RFA.
  • Hiromichi Aono, Yoshiteru Itagaki, Yoshihiko Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 126 (2) 406 - 414 0925-4005 2007/10 [Peer-reviewed]
     Scientific journal 
    Carbon dioxide sensing performance of gas sensors using a NASICON (Na3Zr2Si2PO12) solid electrolyte and a Li2CO3-based auxiliary phase was examined. Gradual changes (drifts) in the EMF level with time were observed for the sensor using only Li2CO3 as an auxiliary electrode. A new auxiliary electrode material based on Li2CO3 and Nd2O3 was developed to improve the sensing stability. The mixture of Li2CO3 and Nd2O2+2x(CO3)(1-x)Li-2x was stable to humidity. The Nd2O2+2x(CO3)(1-x)Li-2x phase between an auxiliary electrode and NASICON acted as a stable diffusion boundary layer. For the mixture of Na2CO3 and Nd2O3, a si in i I ar treatment induced formation of only Nd2O2CO3. A higher reactivity of the Li+ ions with Nd2O2CO3 and a lower reactivity of the Na' ions effectively stabilized the diffusion boundary layer. (C) 2007 Elsevier B.V. All rights reserved.
  • Masahiro Furukawa, Takuji Iseya, Shun Itoh, Akane Anzai, Keiko Sato, Masato Kurihara, Masatomi Sakamoto, Hirornichi Aono, Yoshihiko Sadaoka, Satoshi Hamakawa, Yasushi Hoshi, Fujio Mizukami
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 社団法人日本セラミックス協会 115 (1346) 640 - 642 1882-0743 2007/10 Scientific journal 
    Surface morphology of perovskite-type oxide, LaFeO3, prepared by thermal decomposition of Fe(III)La(III) heteronuclear coordination polymer, La[Fe(CN)(6)] center dot nH(2)O, was compared with those of LaFeO3 obtained by two conventional preparation methods, solid-state reaction of Fe2O3 and La2O3 and pyrolysis of a co-precipitated [Fe(OH)(3) + La(OH)(3)] precursor. At 1273 K, the first method gave LaFeO3 with sub micro meter-sized pores being highly ordered. At the same temperature, the LaFeO3 particles with various sizes from nano-to micrometer in diameter and the highly sintered LaFeO3 were obtained by solid state reaction and co-precipitation method, respectively.
  • Masahiro Furukawa, Takuji Iseya, Shun Itoh, Akane Anzai, Keiko Sato, Masato Kurihara, Masatomi Sakamoto, Hirornichi Aono, Yoshihiko Sadaoka, Satoshi Hamakawa, Yasushi Hoshi, Fujio Mizukami
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 115 (1346) 640 - 642 1882-0743 2007/10 Scientific journal 
    Surface morphology of perovskite-type oxide, LaFeO3, prepared by thermal decomposition of Fe(III)La(III) heteronuclear coordination polymer, La[Fe(CN)(6)] center dot nH(2)O, was compared with those of LaFeO3 obtained by two conventional preparation methods, solid-state reaction of Fe2O3 and La2O3 and pyrolysis of a co-precipitated [Fe(OH)(3) + La(OH)(3)] precursor. At 1273 K, the first method gave LaFeO3 with sub micro meter-sized pores being highly ordered. At the same temperature, the LaFeO3 particles with various sizes from nano-to micrometer in diameter and the highly sintered LaFeO3 were obtained by solid state reaction and co-precipitation method, respectively.
  • Mitsuru Yamauchi, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 115 (1342) 365 - 369 1882-0743 2007/06 [Peer-reviewed]
     Scientific journal 
    The heat-treatment of a mixture of Li2CO3 and R2O3 (R = La and Nd) in CO2 induced the formation of a rare-earth oxycarbonate followed by the lithium incorporation into the rare-earth oxycarbonate during the heating process. The formed oxyearbonates were related to the hexagonal structure with P6(3)mmc. The c-lattice parameter increased and the a-lattice parameter slightly decreased with an increase in the lithiation degree. The lithiation degree y for the R2O2+2y(CO3)(1-y)Li-2y system increased with an increase in the heat treatment temperature in CO2.
  • Mitsuru Yamauchi, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 114 (6) 363 - 369 0914-5400 2007/06 [Peer-reviewed]
     
    The heat-treatment of a mixture of Li2CO3 and R 2O3 (R = La and Nd) in CO2 induced the formation of a rare-earth oxycarbonate followed by the lithium incorporation into the rare-earth oxycarbonate during the heating process. The formed oxycarbonates were related to the hexagonal structure with P63mmc. The c-lattice parameter increased and the a-lattice parameter slightly decreased with an increase in the lithiation degree. The lithiation degree y for the R2O2+2y (CO3)1-yLi2y. system increased with an increase in the heat treatment temperature in CO 2.
  • Yoshiteru Itagaki, Masami Mori, Yuuki Hosoya, Hiromichi Aono, Yoshihiko Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 122 (1) 315 - 320 0925-4005 2007/03 [Peer-reviewed]
     Scientific journal 
    Novel sensing materials of tri-metallic perovskite oxides, SmFe1-xCoxO3 (x = 0-1.0), were applied for a conductometric O-3 and NO2 gas sensor. Fine particles of the oxides were prepared by pyrolysis of corresponding cyano-complexes, Sm[Fe1-xCox(CN)(6)](.)4H(2)O. The conductivity in air increased with an increase in the Co content. This increment in the conductivity reduced the operating temperature for a reliable conductivity measurement from 250 degrees C for x = 0 to 150, 100 and 80 degrees C for x = 0.05, 0.1 and 0.15, respectively. Furthermore, the measurement at room temperature was possible for x >= 0.2. In 0.4 ppm O-3, a large response (S > 100) was obtained for x =0-0.15 at the above operating temperatures. While in 10 ppm NO2, the elements of x = 0.05-0.5 exhibited the maximal response at 200 degrees C. The Co-added oxides showed good response and recovery behavior, compared to SmFeO3 even at low temperature. (c) 2006 Elsevier B.V. All rights reserved.
  • Heat generation ability under AC magnetic field of sized nano MgFe2O4 ferrite powder prepared by bead milling
    Proc. of 24th International Japan-Korea Seminar on Ceramics 635 - 638 2007
  • Computer simulation of heat generation ability in AC magnetic field for Ti tube filled with ferrite powder
    Proc. of 24th International Japan-Korea Seminar on Ceramics 609-612 2007
  • Nano Structured Perovskite-type Oxides with Rare Earth for Semiconductive Gas Sensor
    Annual Journal of Engineering 6 63 - 73 2007
  • Shinfuku Nomura, Shinobu Mukasa, Hiroshi Yamasaki, Tsunehiro Maehara, Hiromichi Aono, Hiroyuki Kikkawa, Koichi Satou, Syungo Yukumi, Yuji Watanabe
    HEAT TRANSFER ENGINEERING 28 (12) 1017 - 1022 0145-7632 2007 [Peer-reviewed]
     Scientific journal 
    The purpose of this study is to elevate the temperature and induce necrosis tumor cells that include ferrite powder to 50-60 degrees C by applying an alternating magnetic field. The achieved temperature is higher when compared to the conventional hyperthermia methods. We performed an experiment in which a high-water content agar phantom that was used as a quasi-tissue had 50 nm-10 mu m magnesium ferrite (MgFe2O4) dispersed in it and was then heated to a level of 190-700 kHz. The results show that the temperature of the phantom is higher for higher frequencies, larger particle sizes, and higher quantities of dispersed ferrite powder. Also, taking into account heat generation due to the magnetic powder, heat generation due to tissue metabolism, and the cooling effect of the blood flow, we solved the thermal equation related to local thermal therapy. Small differences in the distribution of ferrite powder affect the temperature increase of the tissue and the area where cell necrosis is induced.
  • HIRAZAWA H., Uchihara Kodai, Aono Hiromichi, Hiraoka Koichi, Naohara Takashi, Nomura Shinfuku, Maehara Tsunehiro, Watanabe Yuji
    Japanese journal of applied physics Pt. 1 Regular papers, brief communications & review papers Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics 45 (11) 8673 - 8675 0021-4922 2006/11 
    Needle-type materials were studied for the application of thermal coagulation therapy in an AC magnetic field. We found that the Ti tube filled with ferrite powder as the core had a high heat generation ability in an AC magnetic field. Although the Ti tube without the ferrite powder or Ti rod showed poor heat generation abilities, the temperature was significantly increased by the existence of ferrite powder in the tube. In this case, the ferrite powder seems to improve the eddy loss for the Ti tube. The maximum heat generation ability was obtained for the Ti tube that contained MgFe2O 4 powder in the examined Ti tube with some ferrites. © 2006 The Japan Society of Applied Physics.
  • NAOHARA Takashi, AONO Hiromichi, HIRAZAWA Hideyuki, MAEHARA Tsunehiro, WATANABE Yuji
    Materia Japan 日本金属学会 45 (9) 664 - 669 1340-2625 2006/09 [Invited]
     Research society
  • Hiromichi Aono, Nobuyuki Kondo, Haruo Katagishi, Masato Kurihara, Masatomi Sakamoto, Yoshihiko Sadaoka
    JOURNAL OF MATERIALS SCIENCE 41 (16) 5339 - 5345 0022-2461 2006/08 [Peer-reviewed]
     Scientific journal 
    Heteronuclear Bi1-xLax [Fe(CN)(6)]center dot nH(2)O complexes were synthesized, and their crystal structures and thermal decomposition process were investigated by X-ray diffraction (XRD), thermogravimetry analysis (TGA), Auger electron spectroscopy (AES) with scanning electron microscope (SEM), and transmission electron microscopy (TEM). The crystal system of the complexes was orthorhombic having n = 4 for x = 0-0.7 and was hexagonal having n = 5 for x = 1.0. Their mixture was confirmed for x = 0.8 and 0.9. The lattice parameters for the orthorhombic increased with increasing the x value for the complexes. The single phase of trimetallic perovskite-type Bi1-xLaxFeO3 was obtained by its thermal decomposition at low temperature. The crystal system was hexagonal for BiFeO3 (x = 0) and orthorhombic for x = 0.1-1.0. In the case of the decomposed perovskite sample, the lattice parameters decreased with increasing x values for Bi1-xLaxFeO3. The particle size was ca. 30 nm for Bi0.2La0.8FeO3 obtained by thermal decomposition at 500 degrees C and it grew with an increase in decomposition temperature. For the Bi0.5La0.5FeO3, AES showed that the elemental distributions of Bi, La, and Fe on the surface were very homogeneous for the sample decomposed at 700 degrees C.
  • Mitsuru Yamauchi, Yoshiteru Itagaki, Hirornichi Aono, Yoshihiko Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 114 (1331) 648 - 650 1882-0743 2006/07 [Peer-reviewed]
     Scientific journal 
    Reactivity of the mixed powder of Li2CO3 with several metal oxides (Y2O3, Al2O3, ZrO2, SiO2 and ZrSiO4) in synthetic air and 100% CO2 was examined to develop a high temperature repeatable CO2 absorbent. The mixture of Li2CO3 and Y2O3 in molar ratio of 1:1 was stable in CO2 up to 950 degrees C but decomposed to form LiYO2 at around 850 degrees C in synthetic air (N-2 79%+O-2 21%, CO2<0.5 ppm). The newly formed LiYO2 started to absorb the CO2 at 300 degrees C with the reaction of 2LiYO(2)+CO2 -> Li2CO3+Y2O3. Since the mixture was fairly stable in CO2 up to 980 degrees C, the reversed reaction directed to CO2 emission was not observed in CO2. LiYO2 is a new material for a CO2 absorbent available in a wide range of temperature.
  • YAMAUCHI Mitsuru, ITAGAKI Yoshiteru, AONO Hiromichi, SADAOKA Yoshihiko
    Journal of the Ceramic Society of Japan 公益社団法人日本セラミックス協会 114 (1331) 648 - 650 1882-1022 2006/07 
    Reactivity of the mixed powder of Li_2CO_3 with several metal oxides (Y_2O_3, Al_2O_3, ZrO_2, SiO_2 and ZrSiO_4) in synthetic air and 100% CO_2 was examined to develop a high temperature repeatable CO_2 absorbent. The mixture of Li_2CO_3 and Y_2O_3 in molar ratio of 1:1 was stable in CO_2 up to 950℃ but decomposed to form LiYO_2 at around 850℃ in synthetic air (N_2 79%+O_2 21%, CO_2<0.5 ppm). The newly formed LiYO_2 started to absorb the CO_2 at 300℃ with the reaction of 2LiYO_2+CO_2→Li_2CO_3+Y_2O_3. Since the mixture was fairly stable in CO_2 up to 980℃, the reversed reaction directed to CO_2 emission was not observed in CO_2. LiYO_2 is a new material for a CO_2 absorbent available in a wide range of temperature.
  • S Nomura, S Mukasa, T Miyoshi, N Okabe, T Maehara, H Aono, H Kikkawa, K Satou, S Yumi, Y Watanabe
    JOURNAL OF MATERIALS SCIENCE 41 (10) 2989 - 2992 0022-2461 2006/05 Scientific journal 
    The purpose of this study is to investigate the thermal characteristics of Mg1-XCaXFe2O4 ferrite powder by applying AC magnetic field and to predict the effect of thermal coagulation in vivo. We found that heating characteristics of the ferrite powder became greater as the frequency through the 400 kHz to 700 kHz range. The highest heat generation was attained using 7-15 nm ferrite powder. We also carried out a heat transfer simulation in which we were able to demonstrate that this material has sufficient heat generating characteristics to thermally coagulate a tumor cell and that it is possible to predict the range of the coagulation from the present simulation. (c) 2006 Springer Science + Business Media, Inc.
  • N Takeda, Y Itagaki, H Aono, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 115 (1) 455 - 459 0925-4005 2006/05 Scientific journal 
    The compacted sinters of Ln(9.33+x/3)Si(6-x)Al(x)O(26) (0 <= x <= 2.0), (Ln=La, Nd and Sin) are composed of an apatite-like phase with a hexagonal structure. The existence of Ln(2)SiO(5) was confirmed for x <= 1.0 as a minor product, but its formation was suppressed by the increasing Al-content. The densification of the sinters was also improved by partially replacing Si4+ with Al3+. For all the Ln systems, the highest ionic conductivity was observed at x=1.5 in ambient air. The compacted sinters were used as a potentiometric oxygen sensor. The concentration dependence of EMF was well expressed by the Nernst equation, Delta E-obs=(RT/nF) ln (P-O2(I)/P-O2(II)). Furthermore, the electron number n is comparable to the theoretical value of 4. The sensing characteristics of the sinters are comparable to those of the sensors with 3 and 8 mol% YSZ. (c) 2005 Published by Elsevier B.V.
  • Sengo Kobayashi, Hiroko Okano, Kiyomichi Nakai, Hiromichi Aono
    JOURNAL OF THE JAPAN INSTITUTE OF METALS 日本金属学会 70 (4) 330 - 336 0021-4876 2006/04 [Peer-reviewed]
     Scientific journal 
    Amorphous and crystallized calcium phosphate (Ca-P) coatings on Ti substrate have been investigated by X-ray photoelectron spectroscopy (XPS). The Ca-P coating on Ti substrate was performed by radio frequency magnetron sputtering of a sintered hydroxyapatite (HAp) target. As-sputtered Ca-P coating having 1.81 of Ca/P ratio was amorphous. Annealing the as-sputtered amorphous coating at 600 degrees C resulted in crystallized coating into HAp and tetracalcium phosphate (TTCP). The XPS profile of amorphous coating is almost the same as that of annealed coating. The XPS profile of oxygen in the amorphous coating shows that oxygen atom combines with both phosphorus and calcium atoms, indicating the amorphous coating contains fundamental chemical bonds of both HAp and TTCP.
  • NAOHARA Takashi, MASAKI Daisuke, HIRAZAWA Hideyuki, AONO Hiromichi, MAEHARA Tsunehiro, WATANABE Yuji
    Annual journal of engineering, Ehime University 愛媛大学 5 74 - 78 1348-9895 2006/03 
    An attempt has been made to obtain a medical material applicable to the ablation therapy of liver cancer. The heating property of the needle-shaped Mg-ferrite (MgFe2O4) prepared using a sintering technique was studied under an external AC magnetic field at 370 kHz. The increase in temperature (ΔT) was as high as 32℃ for the stick of 1.5 mm in diameter, while the complementary use of these three sticks achieved marked ΔT enhancement of 58℃. In a rabbit liver, high-frequency inductive heating of the needle-shaped Mg-ferrite resulted in the local destruction of the tissue due to coagulative necrosis.
  • N Kondo, H Itoh, M Kurihara, M Sakamoto, H Aono, Y Sadaoka
    JOURNAL OF ALLOYS AND COMPOUNDS 408 1026 - 1029 0925-8388 2006/02 Scientific journal 
    The heteronuclear Ln[Fe(CN)(6)]center dot nH(2)O (Ln=La, Gd, and Lu) complexes were synthesized by the mixing of (NH4)(3)[Fe(CN)(6)] and Ln(NO3)(3) methanol solutions as a new method. Their thermal decomposition products were then investigated. Although the yield of the Ln[Fe(CN)(6)]center dot nH(2)O complexes was ca. 20% for the well-known method in a water solution, it was improved to ca. 90% using this new method. The X-ray diffraction (XRD) patterns of the complexes agreed with those of the Ln[Fe(CN)(6)]center dot nH(2)O single phase for all the examined Ln systems. The LnFeO(3) single phase was obtained by the thermal decomposition of the synthesized heteronuclear complexes for Ln = La, Gd, and Lu. (c) 2005 Elsevier B.V. All rights reserved.
  • 兵頭 健生, 青野 宏通, 飯田 泰広
    化学センサ 化学センサ研究会 22 (1) 20 - 34 2006
  • Naohara Takashi, Aono Hiromichi, Hirazawa Hideyuki, Maehara Tsunehiro, Watanabe Yuji
    Bulletin of the Japan Institute of Metals The Japan Institute of Metals and Materials 45 (9) 664 - 669 1340-2625 2006 Scientific journal
  • Mitsuru Yamauchi, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    Journal of the Ceramic Society of Japan 114 (1331) 648 - 650 1348-6535 2006 Scientific journal 
    Reactivity of the mixed powder of Li2CO3 with several metal oxides (Y2O3, Al2O3, ZrO 2, SiO2 and ZrSiO4) in synthetic air and 100%CO2 was examined to develop a high temperature repeatable CO 2 absorbent. The mixture of Li2CO3 and Y 2O3 in molar ratio of 1: 1 was stable in CO2 up to 950°C but decomposed to form LiYO2 at around 850°C in synthetic air (N2 79% + O2 21%, CO2 < 0.5 ppm). The newly formed LiYO2 started to absorb the CO2 at 300°C with the reaction of 2LiYO2 + CO2→Li 2CO3 + Y2O3. Since the mixture was fairly stable in CO2 up to 980°C, the reversed reaction directed to CO2 emission was not observed in CO2. LiYO2 is a new material for a CO2 absorbent available in a wide range of temperature.
  • H Aono, S Miyanaga, Y Sadaoka
    ELECTROCHEMISTRY 電気化学会 73 (9) 791 - 797 1344-3542 2005/09 Scientific journal 
    Potentiometric gas sensors using a Ni reference electrode closed in a Na+ conducting Na2O-Al2O3-4SiO(2) glass were investigated for detection Of CO2 and Cl-2 sensing. An electric potential for the reference electrode was fixed by utilization of the Ni reference electrode. For the CO2 Sensor using the Na2CO3 auxiliary phase and Ni reference electrode, the EMF responded to changes in the CO2 gas concentration between 10 ppm and 10000 ppm. The EMF of the CO2 sensor using the Ni reference electrode also responded to a decrease in the O-2 gas concentration. However, the EMF was not fixed when the Pt reference electrode was utilized instead of Ni. The O-2 gas concentration for the reference electrode would be equilibrated by the Ni, NiO, and oxygen diffused from the solid electrolyte. For the Cl-2 gas sensor using the NaCl auxiliary phase, the EMF responded even to low Cl-2 gas concentrations below 10 ppm and also a ppb-level gas under humid conditions.
  • H Aono, S Miyanaga, Y Sadaoka
    ELECTROCHEMISTRY 73 (9) 791 - 797 1344-3542 2005/09 Scientific journal 
    Potentiometric gas sensors using a Ni reference electrode closed in a Na+ conducting Na2O-Al2O3-4SiO(2) glass were investigated for detection Of CO2 and Cl-2 sensing. An electric potential for the reference electrode was fixed by utilization of the Ni reference electrode. For the CO2 Sensor using the Na2CO3 auxiliary phase and Ni reference electrode, the EMF responded to changes in the CO2 gas concentration between 10 ppm and 10000 ppm. The EMF of the CO2 sensor using the Ni reference electrode also responded to a decrease in the O-2 gas concentration. However, the EMF was not fixed when the Pt reference electrode was utilized instead of Ni. The O-2 gas concentration for the reference electrode would be equilibrated by the Ni, NiO, and oxygen diffused from the solid electrolyte. For the Cl-2 gas sensor using the NaCl auxiliary phase, the EMF responded even to low Cl-2 gas concentrations below 10 ppm and also a ppb-level gas under humid conditions.
  • Y Hosoya, Y Itagaki, H Aono, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 108 (1-2) 198 - 201 0925-4005 2005/07 Scientific journal 
    The conductance changes of SmFeO3 based p-type gas sensor with ozone in air with and without VOCs were examined. The conductance for this sensor was responsible in sub-ppm levels ozone at the temperatures above 240 degrees C and the sensitivity decreased with an increase in the working temperature. It is expected that the sensitivity in 0.01 ppm ozone estimated to be ca. 10 at 290 degrees C. The sensing characteristic is promising to monitor the environmental air quality regarding with ozone. The conductance for ozone was decreased by the contamination of same levels VOCs. This is mainly due to the decrease in actual concentration of ozone by the reaction with contaminated VOCs. The developed sensor is a very promising candidate for the detection of ozone in sub-ppm levels and for the contaminated levels with several VOCs in monitoring environment. (c) 2004 Elsevier B.V. All rights reserved.
  • T Okamoto, Y Shimamoto, N Tsumura, Y Itagaki, H Aono, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 108 (1-2) 346 - 351 0925-4005 2005/07 Scientific journal 
    The CO2 sensing characteristics of the Pt,Na2CO3/Na+-electrolyte//YSZ/Pt structure were examined under dry conditions. To achieve a good interconnection between YSZ and a dense electrolyte, the Na2O-Al2O3-4SiO(2) melt was used as the electrolyte. The electrolyte was stable in syn-air and also in 100% CO2. The sensing characteristics were strongly influenced by the preparation scheme of the auxiliary electrode with Na2CO3. For the sensor with the auxiliary electrode of Na2CO3 formed by the heating of a coated Vaseline mixture with Na2CO3, the tendency to increase the emf was depressed. This observed improvement was attributed to the reduced crystallization and aggregation of Na2CO3 particles due to the coexistence of the oxidized Vaseline in the forming procedure. (c) 2004 Elsevier B.V. All rights reserved.
  • H Aono, H Hirazawa, T Naohara, T Maehara, H Kikkawa, Y Watanabe
    MATERIALS RESEARCH BULLETIN 40 (7) 1126 - 1135 0025-5408 2005/07 Scientific journal 
    Nano-sized FeFe2O4 ferrite powder for local thermal coagulation therapy was synthesized by a reverse coprecipitation method. The crystal diameter for the samples from the reverse coprecipitation method was smaller than that from a normal coprecipitation method. The crystal diameter increased with an increase in the synthesized temperature for both methods. The maximum increasing temperature under the AC magnetic field was at around a 12 nm crystal diameter. The FeFe2O4 powder was oxidized to Fe2O3 by calcination at 600 degrees C in ambient air. The heating ability almost depended on the hysteresis loss value. Although the increased temperature under the AC magnetic field for the fresh FeFe2O4 sample was very close to that for the commercialized MgFe2O4 powder, it was gradually decreased for FeFe2O4 with time in ambient air. (c) 2005 Elsevier Ltd. All rights reserved.
  • N Tsumura, A Kuramoto, Y Shimamoto, H Aono, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 113 (1316) 269 - 274 1882-0743 2005/04 [Peer-reviewed]
     Scientific journal 
    The thermal stability of solium aluminium silicates and their reactivity to alkali carbonates were investigated in view of their application as CO2 gas sensors. A nepheline phase was very stable, since the peak position of the X-ray diffraction pattern was hardly influenced by either heat treatment or humidification up to 800 degrees C. A distorted carnegieite phase (like-carnegieite) transformed into the nepheline phase at 500 degrees C under a humid condition, while under a dry condition, it was stable up to 800 degrees C but transformed into the nepheline phase at 900 degrees C. For mixtures with alkali carbonates, the nepheline phase was most stable even under the humid condition at temperatures below 500 degrees C. When the mixtures were heated at NOT, the nepheline phase reverted to the like-carnegieite phase and alkali silicates, such as Na2SiO3, Li2SiO3 and LOA, formed as by-products. For Na2O-Al2O3-4SiO(2) sintering mixtures with Li2CO3, the like-carnegieite phase transformed into the nepheline phase at 500 degrees C. The nepheline phase was stable up to 1000 degrees C even under the humid condition and LOA formed as a by-product.
  • H Aono, H Hirazawa, T Ochi, T Nachara, K Mori, Y Hattori, T Maehara, H Kikkawa, Y Watanabe
    CHEMISTRY LETTERS 34 (4) 482 - 483 0366-7022 2005/04 Scientific journal 
    Fine Mg1-xCaxFe2O4 ferrite powders for local thermal coagulation therapy were synthesized by a reverse coprecipitation method. The enhancement of temperature under an AC magnetic field was improved by the partial Ca2+ substitution. A high heat ability was obtained for the samples calcined at 300 and 800 degrees C.
  • Naoki Tsumura, Ayuko Kuramoto, Youichi Shimamoto, Hiromichi Aono, Yoshihiko Sadaoka
    Journal of the Ceramic Society of Japan 113 (1316) 269 - 274 0914-5400 2005 Scientific journal 
    The thermal stability of solium aluminium silicates and their reactivity to alkali carbonates were investigated in view of their application as CO 2 gas sensors. A nepheline phase was very stable, since the peak position of the X-ray diffraction pattern was hardly influenced by either heat treatment or humidification up to 800°C. A distorted carnegieite phase (like-carnegieite) transformed into the nepheline phase at 500°C under a humid condition, while under a dry condition, it was stable up to 800°C but transformed into the nepheline phase at 900°C. For mixtures with alkali carbonates, the nepheline phase was most stable even under the humid condition at temperatures below 500°C. When the mixtures were heated at 600°C, the nepheline phase reverted to the like-carnegieite phase and alkali silicates, such as Na2SiO3, Li2SiO3 and Li 4SiO4, formed as by-products. For Na2O-Al 2O3-4SiO2 sintering mixtures with Li 2CO3, the like-carnegieite phase transformed into the nepheline phase at 500°C. The nepheline phase was stable up to 1000°C even under the humid condition and Li2SiO3 formed as a by-product.
  • T Maehara, K Konishi, T Kamimori, H Aono, H Hirazawa, T Naohara, S Nomura, H Kikkawa, Y Watanabe, K Kawachi
    JOURNAL OF MATERIALS SCIENCE 40 (1) 135 - 138 0022-2461 2005/01 Scientific journal 
    Selection of ferrite powder was carried out to realize a thermal coagulation technique in which tumors are locally heated by an application of alternating magnetic field from external coils. Magnesium ferrite (MgFe2O4) showed the largest increase in temperature (AT) under an alternating magnetic field in all the ferrites examined. For all the samples, AT value under alternating magnetic field was increased with an increase in frequency (200-500 kHz). The heating ability for the Mg-ferrite was ca. 1.4 W/g under alternating magnetic field of 4.0 kA/m (200 W, 370 kHz). The heating ability in alternating magnetic field was clearly depended on the magnitude of the hysteresis loss for the ferrite powder. (C) 2005 Springer Science + Business Media, Inc.
  • Takashi Okamoto, Ayuko Kuramoto, Youichi Shimamoto, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    Proceedings - Electrochemical Society 8 200 - 207 2004/12 
    To develop a monolithic type CO2 gas sensor with Pt,Li 2CO3/Na2O-Al2O3-4SiO 2//YSZ/Pt structure, the reactivity of Li2CO3 and Na2O-Al2O3-4SiO2 (NA4S) was examined. For a newly fabricated sensor with an auxiliary electrode with Li 2CO3, the EMF value increased with time in the initial period and then stable response for CO2 was observed at 460°C. The NA4S was composed with carnegieite-like phase and amorphous SiO2. In the dry condition, the NA4S sinter was stable in air and also in 100 %CO2 but reactive with Li2CO3. Li 2SiO4 and Li2SiO3 phases were detected for NA4S-Li2CO3 mixture heated at around 600°C. For the mixture of amorphous SiO2 and Li 2CO3, Li4SiO4 phase was observed at 600°C in a dry condition and Li2SiO3 phase at 500°C in a humid condition. The observed EMF shifts with time and humidification were interpretable in terms of the formation of lithium silicates and the decomposition of Li4SiO4 to Li 2SiO3.
  • Manabu Fujishima, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    Proceedings - Electrochemical Society 8 66 - 72 2004/12 
    To develop a stable solid-state lithium ionic conductor for potentiometric CO2 gas sensor, LixNd10-xSi6O 27-x (x=1-3) sinters were prepared. The x=2 and 3 sinters formed single phases, while a trace of Li2SiO3 phase was confirmed for x=1. The dense electrolyte was formed for Li2Nd 8Si6O25 by sintering at 1300°C while for the other examined materials, were porous. Li2CO3 mixed with the Li2Nd8Si6O25 was remarkably stable and not decomposed until ca. 950°C. For comparison, single decomposition of the Li2CO3 was observed at 700°C. It is expected that the Li2CO3 phase as an auxiliary electrode formed of the electrolyte with Li2Nd8Si 6O25 is stable at the working temperature of the potentiometric CO2 sensor with the structure of CO2, Pt/Li2CO3/Li+-conductor/Pt, ref. gas. The EMF change was explained by the Nernst's equation, E=Eo- (RT/nF)ln(Pco2) and the electron number, n, was slightly higher than 2 in the temperature range of 400°C and 500°C.
  • Naoki Takeda, Yoshiteru Itagaki, Hiromichi Aono, Yoshihiko Sadaoka
    Proceedings - Electrochemical Society 8 194 - 199 2004/12 
    Nd10(SiO4)6O3 and Nd 9.33+x/3Si6-xAlxO26 (x=0 to x=2.0) with apatite-type crystal structure were synthesized by the solid-state reaction at 1600°C and the sintered discs were examined by XRD and SEM. Nd 10(SiO4)6O3 and Nd 9.33+x/3Si6-xAlxO26 (x=0 to x=1.0) solid electrolytes contained Nd2SiO5 as a minor product and the content decreased with an increase in the Al content. The single phase was obtained and sinterability was improved for x=1.5. The highest ionic conductivity in air was observed for x=1.5 whose sample was applied for a potentiometric oxygen gas sensor. The concentration dependence of EMF was expressed by the Nernst's relationship and the electron number was estimated to 4.0 at 400°C and higher. The hysteresis of EMFs in an increasing and the decreasing for O2 gas concentration was also determined and its degree monotonically decreased with an increase in the operating temperature.
  • N Kondo, A Yokoyama, M Kurihara, M Sakamoto, M Yamada, M Miyake, T Ohsuna, H Aono, Y Sadaoka
    CHEMISTRY LETTERS 33 (9) 1182 - 1183 0366-7022 2004/09 Scientific journal 
    Fluorescent properties of Eu(III) in the bulk- and nanocrystals of coordination polymer, Eu[Co(CN)(6)].4H(2)O, were compared with those of EuCl3.6H(2)O. Fluorescent intensity of bulk crystals was greatly enhanced on forming the coordination polymer, whereas that of nanocrystals was little affected. These results were discussed considering the coordination surroundings around Eu(III) located on the crystal surface.
  • K Konishi, T Maehara, T Kamimori, H Aono, T Naohara, H Kikkawa, Y Watanabe, K Kawachi
    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 272 2428 - 2429 0304-8853 2004/05 Scientific journal 
    In order to realize a thermal coagulation technique in which tumors are locally heated up to 60-80 degreesC by inductive heating and necrotized, selection of ferrite powder and frequency are performed. We investigate the heating properties by applying AC magnetic field for various ferrite powders (micrometer size of the particles). The temperature rise for Mg-ferrite (MgFe2O4) powder is the largest around 360 kHz in our samples. It has sufficient heating ability for thermal coagulation therapy against cancer. (C) 2003 Elsevier B.V. All rights reserved.
  • Y Shimamoto, T Okamoto, Y Itagaki, H Aono, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 99 (1) 113 - 117 0925-4005 2004/04 Scientific journal 
    CO2 sensing characteristics were examined in dry condition for Pt, Li2CO3/Na2O-Al2O3-4SiO(2) (NA4S)/YSZ/Pt structure. The electromotive force (emf) value was linearly increased with logarithm of CO2 concentration in the range of 10-10,000 ppm and the electron number was closed to 2.0. The electron number was hardly changed and the activity of alkali metal oxide in NA4S increased with time. As a reason to increase in the activity, the reaction of Li2CO3 as an auxiliary electrode with SiO2 in NA4S layer and the formation of lithium silicates are considered. The formation of Li2SiO3 was accelerated by using H2O, methanol or ethanol instead of alpha-terpineol as an additive for the mixing of Li2CO3 and silica. It was concluded that to depress the reaction with Li2CO3 and silica, the use of Li2CO3 mixed with alpha-terpineol for an auxiliary electrode was preferable. (C) 2003 Elsevier B.V. All rights reserved.
  • Y Shimamoto, T Okamoto, H Aono, L Montanaro, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 99 (1) 141 - 148 0925-4005 2004/04 Scientific journal 
    CO(2) sensing characteristics were examined in dry condition for Pt, Na(2)CO(3)/Na(2)O-Al(2)O(3)-4SiO(2)//YSZ/Pt structure. After settled at the working temperature at 460degreesC, emf was gradually decreased with time and then increased. The drift to decrease the emf observed in the initial period is due to the remove of water in Na(2)CO(3) layer with morphological changes. The diffusion of Na ion in Na(2)O-Al(2)O(3)-4SiO(2) layer to YSZ layer is also one of the reason. The increase in the emf observed in the following period is due to the increase in the activity by the reaction of Na(2)CO(3) with SiO(2) in Na(2)O-Al(2)O(3)-4SiO(2) layer. Furthermore, it is confirmed that the reactivity of Na(2)CO(3) with SiO(2) is strongly affected by the preparation method/route of Na(2)CO(3) layer as an auxiliary electrode. (C) 2003 Elsevier B.V. All rights reserved.
  • AONO Hiromichi, HIRASAWA Hideyuki, YANO Jun, NAOHARA Takashi, MAEHARA Tsunehiro, KONISHI Kensuke, WATANABE Yuji
    Annual journal of engineering, Ehime University 愛媛大学 3 59 - 64 1348-9895 2004/03 
    Selection of ferrite powder and suitable frequency were carried out to realize a thermal coagulation technique in which tumors are locally heated to 60-80℃ by an application of alternating magnetic field from external coils after they are stuffed with ferrite powder. Various ferrite powders were heated by an alternating magnetic field in 80kHz-399kHz. In this frequency range, the largest increase in temperature (ΔT) was obtained for the MgFe_2O_4 in all the samples examined. The ΔT value was almost proportional to the applied power and the weight of the powder. The heating ability for the Mg-ferrite was ca. 86 J・min^<-1>・g^<-1> under AC magnetic field (200W, 370kHz).
  • M Tomoda, S Okano, Y Itagaki, H Aono, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 97 (2-3) 190 - 197 0925-4005 2004/02 Scientific journal 
    The conductance changes of SmFeO3-based p-type gas sensor and n-type SnO2 gas sensor (TGS2600), with volatile organic compounds (VOCs) and NO2 in air were examined. Prediction of the contaminated levels with VOCs became difficult when NO2 levels were changed and also vice versa. The use of one sensor was poor to detect a level of contaminated air's quality. By using at least two SmFeO3 sensor operating at a different temperature, prediction of each contaminated level with VOCs and NO2 became possible. Furthermore, by the combination with both sensor sub-ppm levels contamination with VOCs and NO2 was interpretable due to a higher sensitivity of TGS2600 for NO2 and of SmFeO3 for VOCs. (C) 2003 Elsevier B.V. All rights reserved.
  • E Di Bartolomeo, N Kaabbuathong, A D'Epifanio, ML Grilli, E Traversa, H Aono, Y Sadaoka
    JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 24 (6) 1187 - 1190 0955-2219 2004 Scientific journal 
    Solid-state NO2 sensors based on yttria stabilized zirconia (YSZ), an O2- conductor, combined either with an n- (WO3) or a p-type semiconducting oxide (LaFeO3) or a mixed electronic and ionic conductor (La0.8Sr0.2FeO3) were investigated. Platinum parallel finger electrodes were applied on the surface of tape-casted YSZ layers and attached with gold wires for current collection. Nanocrystalline perovskite powders were prepared using different chemical methods: LaFeO3 by the thermal decomposition of the LaFe-hexacyanide complex, and La0.8Sr0.2FeO3 by a sol-gel route. A sub-micrometric commercial WO3 powder was used. The oxide powders were mixed with a screen-printing oil and deposited on one Pt finger electrode. The presence of the oxide powder makes one of the electrodes different from the other in terms of catalytic activity, specific surface area, gas adsorption and reaction kinetics. Both electrodes were wholly exposed to the same gas atmosphere, without using reference air. The sensors were investigated at fixed temperature (450-700 degreesC) by measuring the electromotive force (EMF) at different concentrations of NO2 and CO in air in the range 20-1000 ppm. A fast and stable response was measured for all the tested sensors. An EMF of opposite sign was measured for p- and n-type semiconducting based sensors upon exposure to the same gas. After increasing the grain size of the nano-structured La0.8Sr0.2FeO3 powder by a heat treatment at 900 degreesC for 4 h, the response to NOx became small, slow and unstable. (C) 2003 Elsevier Ltd. All rights reserved.
  • H Aono, MA bin Idris, Y Sadaoka
    SOLID STATE IONICS 166 (1-2) 53 - 59 0167-2738 2004/01 Scientific journal 
    The monoclinic phase (P2(1)/n) was formed for 0 less than or equal to x less than or equal to 0.6 and the NASICON-type rhombohedral phase (R3c) was obtained for the region 0.8 less than or equal to x less than or equal to 1.2 in the Li3-2xCr2-xTax(PO4)(3) system. The activation energy for Li+ migration was ca. 0.45 eV for the monoclinic structure and ca. 0.36 eV for the rhombohedral structure. The maximum conductivity of 8.4 x 10(-6) S cm(-1) at 298 K was obtained for x = 0.8 of the Li3-2xCr2-xTax(PO4)(3) system. The conductivity of LiCrTa(PO4)(3) was enhanced about three to five times by the addition of the lithium salt due to the improvement of the sinterablity. The maximum conductivity was 2.4 x 10(-5) S cm(-1) at 298 K for LiCrTa(PO4)(3)-0.2Li(3)BO(3) (C) 2004 Elsevier B.V. All rights reserved.
  • CRYSTALLIZATION OF RF-MAGNETRON SPUTTERED AMORPHOUS CALCIUM PHOSPHATE
    Phosphorous Research Bulletin 17 (10) 246 - 253 2004
  • 松口 正信, 飯田 泰広, 青野 宏通
    化学センサ 化学センサ研究会 20 (3) 129 - 153 2004
  • ハイドロキシアパタイト(HAp)/Ti接合界面組織
    小林千悟, 喜多下幸太郎, 青野宏通, 仲井清眞, 桑野範之
    Boundary 19 (11) 31 - 34 2003/11 Research society
  • Y Shimamoto, H Aono, N Kondo, M Kurihara, M Sakamoto, Y Sadaoka
    CHEMISTRY LETTERS 32 (10) 906 - 907 0366-7022 2003/10 Scientific journal 
    A heteronuclear complex, La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O, was synthesized and its thermal decomposition products were studied. Results of chemical analysis and TGA agreed with theoretical values for La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O complex. The La2CuO4 single phase having ca. 100 nm in crystal size was obtained by the thermal decomposition at 700 degreesC for 1 h.
  • Y Shimamoto, H Aono, N Kondo, M Kurihara, M Sakamoto, Y Sadaoka
    CHEMISTRY LETTERS 32 (10) 906 - 907 0366-7022 2003/10 Scientific journal 
    A heteronuclear complex, La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O, was synthesized and its thermal decomposition products were studied. Results of chemical analysis and TGA agreed with theoretical values for La2Cu(C4O4)(4)(H2O)(16)(.)2H(2)O complex. The La2CuO4 single phase having ca. 100 nm in crystal size was obtained by the thermal decomposition at 700 degreesC for 1 h.
  • 小林 千悟, 喜多下 幸太郎, 青野 宏通
    バウンダリ- コンパス社 19 (9) 31 - 34 0916-2402 2003/09
  • H Aono, E Traversa, M Sakamoto, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 94 (2) 132 - 139 0925-4005 2003/09 Scientific journal 
    Finer perovskite-type LnFeO(3) (Ln = La, Nd, Sm, Gd, and Dy) powders were prepared by the thermal decomposition of heteronuclear complexes, Ln[Fe(CN)(6)].nH(2)O. The prepared LnFeO(3) showed a p-type semiconductive behavior and the highest enhancement of conductance due to NO2 exposure was observed for SmFeO3 sensor. The atomic ratio of adsorbed oxygen O-ad increased with the surface coverage of Ln, expressed as Ln/(Ln + Fe). Experimentally, the atomic ratio of Ln/(Ln + Fe) was estimated to around 0.6 and the largest value, 0.65, was observed for SmFeO3. For SmFeO3, the distance between the central Sm ion and nearest four ions of oxygen is comparable with the sum of crystal radius of Sm3+ (C.N. = 6) and O2-, and the distance between Sm ion and fifth and higher oxygen is longer than the expected length form Shannon's crystal radius. The observed longer length for C.N. = 5 or more is comparable to the length for Sm2+-O bond. The possible valence of Ln ion is directly related with the electron configuration of Ln species and only for Sm the existence of the divalent cation is expected. The divalency of the Sm3+ in the surface layer is suggested by the configurations of coordinated oxygen. The highest sensitivity for NO2 observed for SmFeO3 would be attributed to the formation of Fe defects due to the higher coverage of Ln and the divalency of Sm3+ in SmFeO3. (C) 2003 Elsevier Science B.V. All rights reserved.
  • H Aono, N Kondo, M Sakamoto, E Traversa, Y Sadaoka
    JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 23 (9) 1375 - 1381 0955-2219 2003/08 Scientific journal 
    The heteronuclear LaNi(dhbaen)(NOAH(2)O)(n) complex was synthesized and its thermal decomposition products were analyzed by differential thermal analysis (TG/DTA), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, Auger electron spectroscopy (AES) with scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Hexagonal perovskite-type LaNiO3 having fine particle size was obtained by sintering at 600 degreesC. AFS showed,that the elemental distributions of La, Ni, and O on the surface were very homogeneous for the sample decomposed at 900 degreesC. The LaNiO3 decomposed to La3Ni2O7 and NiO when the heating temperature increases up to 1000 degreesC. Heteronuclear LnNi(dhbaen)(NO3)H2O)(n) complexes (with Ln = Pr, Nd, Sm, and Gd) were also synthesized. The perovskite-type LnNiO(3) phase could not be formed by their thermal decomposition. (C) 2003 Elsevier Science Ltd. All rights reserved.
  • 青野 宏通
    化学センサ 化学センサ研究会 19 (2) 59 - 63 2003
  • H Aono, S Nakano, N Kondo, H Katagishi, M Sakamoto, E Asato, Y Sadaoka
    CHEMISTRY LETTERS (6) 568 - 569 0366-7022 2002/06 Scientific journal 
    The heteronuclear Bi1-xLax[Fe(CN)(6)].nH(2)O complexes were synthesized and their crystal structures were investigated by XRD and TGA. The crystal phase was hexagonal (n = 5) for x = 1.0, and orthorhombic (n = 4) for x = 0-0.7 and their mixture (x = 0.8 and 0.9). The lattice constants for the complexes linearly increased with an increase in the x value. The single phase of the trimetallic perovskite-type Bi0.5La0.5FeO3 was obtained by its thermal decomposition at 500degreesC.
  • H Aono, Y Sadaoka
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 149 (6) H123 - H127 0013-4651 2002/06 Scientific journal 
    The influence of moisture in a test gas containing Cl-2 was investigated for a Cl-2 gas sensor using a NaCl-RuO2 mixed measuring electrode and a composite Na+ conductor of sodium superionic conductor, 40 wt % (Na2O-Al2O3-4SiO(2)). For dried Cl-2 gas, the electron number (n) for the reaction on the electrodes was 1.86 which was very close to the theoretical value n=2.0. When water vapor was added to the Cl-2 measuring gas, the electromotive force (emf) significantly decreased, since the Cl-2 gas concentration was reduced by the reaction with the H2O gas. Based on the calibration curve observed from the relationship between emf and Cl-2 concentration at 450degreesC under dry conditions, it is suggested that the sensor can determine parts per billion levels of Cl-2 gas under ambient conditions. Experimentally, the observed response time became faster with an increase in the flow rate and mainly depended on the exchange time of the test gas. (C) 2002 The Electrochemical Society.
  • Hiromichi Aono, Satoshi Nakano, Nobuyuki Kondo, Haruo Katagishi, Masatomi Sakamoto, Eiji Asato, Yoshihiko Sadaoka
    Chemistry Letters (6) 568 - 569 0366-7022 2002/04 Scientific journal 
    The heteronuclear Bi1-xLax[Fe(CN)6]·nH2O complexes were synthesized and their crystal structures were investigated by XRD and TGA. The crystal phase was hexagonal (n = 5) for x = 1.0, and orthorhombic (n = 4) for x = 0-0.7 and their mixture (x = 0.8 and 0.9). The lattice constants for the complexes linearly increased with an increase in the x value. The single phase of the trimetallic perovskite-type Bi0.5 La0.5FeO3 was obtained by its thermal decomposition at 500°C.
  • H Aono, Y Sadaoka, L Montanaro, E Di Bartolomeo, E Traversa
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 85 (3) 585 - 589 0002-7820 2002/03 Scientific journal 
    CO(2)-gas sensors were fabricated using NASICON-type dense ceramics with new compositions in the Na(3)Zr(2-(X/4))-Si(2-x)P(1+x)O(12) system. The bulk ceramics were prepared from sol-gel-processed powders. Dense electrolytes were obtained for compositions with x = 0.667 and x = 1.333. An improved sinterability was observed with respect to NASICON with conventional composition, which was attributed to liquid-phase sintering. The CO(2)-gas sensors using these dense samples showed a stable electromotive force (emf) response in dry atmosphere that was similar to the theoretical Nernstian value for a two-electron electrochemical reaction. This was observed also for the NASICON sample with composition x = 1.333 that showed a conductivity far lower than that of the NASICON with conventional composition. The emf changed quickly with changes of the CO(2-)gas concentration, and steady-state values were observed. The response time, in adsorption and desorption of CO(2), was very fast, especially at high CO(2) concentrations. The influence of humidity on the CO(2)-sensing performance was investigated. A lower sensitivity and slower response were obtained in humid CO(2) gas, especially at low CO(2) concentrations. CO(2)-sensing measurements at various gas-flow rates were performed to evaluate the reactions occurring at the measuring electrode. The occurrence of a side reaction on the measuring electrode was observed, i.e., the formation of sodium oxides. In dry gas, the reaction took place at low CO(2) concentrations and small now rates, whereas the reaction was strongly enhanced in humid environments and occurred over the entire CO(2) concentration range. However, the sensor performance recovered after switching from humid gas to dry gas. This demonstrated that the humidity affects the emf because of the Na(2)O(x) formation at the electrode, and, thus, the solid electrolyte itself was not degraded by humidity.
  • T Maehara, K Konishi, T Kamimori, H Aono, T Naohara, H Kikkawa, Y Watanabe, K Kawachi
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 41 (3A) 1620 - 1621 0021-4922 2002/03 Scientific journal 
    To develop materials for achieving local hyperthermia, we investigate the heating of various ferrite and metal powders by applying an external AC magnetic field. In comparison with magnetite powder, which has often been used in previous experiments, Mg-ferrite powder is more applicable for achieving local hyperthermia.
  • H Aono, Y Sadaoka, L Montanaro, E Di Bartolomeo, E Traversa
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 85 (3) 585 - 589 0002-7820 2002/03 Scientific journal 
    CO(2)-gas sensors were fabricated using NASICON-type dense ceramics with new compositions in the Na(3)Zr(2-(X/4))-Si(2-x)P(1+x)O(12) system. The bulk ceramics were prepared from sol-gel-processed powders. Dense electrolytes were obtained for compositions with x = 0.667 and x = 1.333. An improved sinterability was observed with respect to NASICON with conventional composition, which was attributed to liquid-phase sintering. The CO(2)-gas sensors using these dense samples showed a stable electromotive force (emf) response in dry atmosphere that was similar to the theoretical Nernstian value for a two-electron electrochemical reaction. This was observed also for the NASICON sample with composition x = 1.333 that showed a conductivity far lower than that of the NASICON with conventional composition. The emf changed quickly with changes of the CO(2-)gas concentration, and steady-state values were observed. The response time, in adsorption and desorption of CO(2), was very fast, especially at high CO(2) concentrations. The influence of humidity on the CO(2)-sensing performance was investigated. A lower sensitivity and slower response were obtained in humid CO(2) gas, especially at low CO(2) concentrations. CO(2)-sensing measurements at various gas-flow rates were performed to evaluate the reactions occurring at the measuring electrode. The occurrence of a side reaction on the measuring electrode was observed, i.e., the formation of sodium oxides. In dry gas, the reaction took place at low CO(2) concentrations and small now rates, whereas the reaction was strongly enhanced in humid environments and occurred over the entire CO(2) concentration range. However, the sensor performance recovered after switching from humid gas to dry gas. This demonstrated that the humidity affects the emf because of the Na(2)O(x) formation at the electrode, and, thus, the solid electrolyte itself was not degraded by humidity.
  • フッ化物イオン伝導体以外のハロゲン化物イオン伝導体
    青野 宏通
    マテリアル インテグレーション (11) 51 - 54 2001/11 [Invited]
     Research society
  • 青野 宏通
    マテリアルインテグレ-ション ティ-・アイ・シ- 14 (11) 51 - 54 1344-7858 2001/11
  • K Manseki, H Sakiyama, M Sakamoto, Y Nishida, H Aono, Y Sadaoka, M Ohba, H Okawa
    SYNTHESIS AND REACTIVITY IN INORGANIC AND METAL-ORGANIC CHEMISTRY 31 (8) 1443 - 1451 0094-5714 2001/09 Scientific journal 
    The copper(II)-gadolinium(III) complex of a phenol-based side-off type di-nucleating ligand was newly synthesized, using N, N'-dimethyl-N,N'-ethylene-di(5-bromo-3-formyl-2-hydroxybenzylamine). Structural analysis revealed that one of the two formyl groups is converted into a hemiacetal group and the two dinuclear CuGd units are bridged by the alcoholic oxygens of acetal groups of each unit to construct the tetranuclear (CuGd)(2) core.
  • H Aono, M Sakamoto, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 109 (5) 419 - 424 1882-0743 2001/05 [Peer-reviewed]
     Scientific journal 
    The thermally decomposed products of the CuRE (dhbaen) (NO3) (dmso)(m)(H2O)(n) complex were investigated by differential thermal analysis (TGA), X-ray diffraction patterns (XRD), energy dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). A mixed phase of RE2O2SO4 and CuO was formed at a low temperature. The particle size of CuO in the mixed phase was estimated to be 30-90 nm by XRD. When the ionic radius of RE3+ ion is small, the RE2O2SO4 phase decomposed and formed a heterometallic RE2Cu2O5 at 850-1100 degreesC, It appears that one dmso directly interacted with the RE ion (RE-O = S(- CH3)(2)) for the complex and the RE-O = S bond remained as RE2O2SO4 after the decomposition. CuO in the mixed phase did not interact with - SO4 which was confirmed by XPS.
  • H Aono, M Tsuzaki, A Kawaura, M Sakamoto, E Traversa, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 84 (5) 969 - 975 0002-7820 2001/05 Scientific journal 
    The heteronuclear LaMn(dhbaen)(OH)(NO3)(H2O)(4) complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at approximately 700 degreesC, The complex and its decomposition products were analyzed using simultaneous thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy, Auger electron spectroscopy (AES), transmission electron microscopy (TEM) characterization, and specific surface area measurements. Although XRD analysis did not show the peaks of LaMnO3 for the sample sintered at 600 degreesC, the presence of polycrystalline LaMnO3 together with an amorphous phase was confirmed by TEM-selected area diffraction, Particle sizes of the samples decomposed at 600 degrees and 700 degreesC were 20 and 50 nm, respectively, For the conventional solid-state reaction method, XRD results showed the formation of a LaMnO3 single phase for the samples fired above 1000 degreesC, However, AES showed that the elemental distributions of La, Mn, and O on the surface were not homogeneous even for the sample sintered at 1200 degreesC. The thermal decomposition of the heteronuclear complex at low temperatures allows the synthesis of single-phase hexagonal LaMnO3 powders having nanosized particles, homogeneous and free of intragranular pores, which are suitable for electroceramics applications.
  • H Aono, M Tsuzaki, A Kawaura, M Sakamoto, E Traversa, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 84 (5) 969 - 975 0002-7820 2001/05 Scientific journal 
    The heteronuclear LaMn(dhbaen)(OH)(NO3)(H2O)(4) complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at approximately 700 degreesC, The complex and its decomposition products were analyzed using simultaneous thermogravimetric and differential thermal analysis (TG/DTA), X-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy, Auger electron spectroscopy (AES), transmission electron microscopy (TEM) characterization, and specific surface area measurements. Although XRD analysis did not show the peaks of LaMnO3 for the sample sintered at 600 degreesC, the presence of polycrystalline LaMnO3 together with an amorphous phase was confirmed by TEM-selected area diffraction, Particle sizes of the samples decomposed at 600 degrees and 700 degreesC were 20 and 50 nm, respectively, For the conventional solid-state reaction method, XRD results showed the formation of a LaMnO3 single phase for the samples fired above 1000 degreesC, However, AES showed that the elemental distributions of La, Mn, and O on the surface were not homogeneous even for the sample sintered at 1200 degreesC. The thermal decomposition of the heteronuclear complex at low temperatures allows the synthesis of single-phase hexagonal LaMnO3 powders having nanosized particles, homogeneous and free of intragranular pores, which are suitable for electroceramics applications.
  • H Aono, M Sato, E Traversa, M Sakamoto, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 84 (2) 341 - 347 0002-7820 2001/02 Scientific journal 
    Perovskite-type SmFeO3 powders were prepared by the thermal decomposition of a heteronuclear complex, Sm(Fe(CN)(6)). 4H(2)O and by solid-state reaction between the corresponding single oxides, Sm2O3 and Fe2O3. The thermal decomposition behavior of the complex was studied by thermogravimetric analysis. X-ray diffractometry was used to investigate the structure of the products from the complex thermal decomposition and the formation of SmFeO2 from the oxide mixture. Powders prepared by both methods were used to deposit thick films onto alumina substrates with comb-type gold electrodes. The microstructure and chemical homogeneity of the film surfaces,were investigated by scanning electron microscopy and Auger electron spectroscopy. Thick SmFeO3 single-phase films having a homogeneous elemental distribution on the surface were obtained when powder prepared by thermal decomposition of the complex was used for deposition, even when the powder was fired at low temperature (800 degreesC), Surface chemical analysis was performed by X-ray photoelectron spectroscopy (XPS), The O Is XPS line was deconvoluted into two peaks, attributed to adsorbed oxygen (O-ad) and oxygen in the lattice (O-lattice). Quantitative analysis showed that the surface coverage of iron, expressed as Fe/(Fe + Sm), was larger for the films prepared using the solid-state reacted powder. Although the O-lattice/(Fe + Sm) atomic ratio was not influenced by the processing procedures (and, thus, by iron surface coverage), the amount of O-ad decreased with increasing iron surface coverage, A model of the SmFeO3 surface was used to determine that the outermost layer of the perovskite-type SmFeO3 prepared from the complex consisted mainly of samarium ions that could each bond four adsorbed oxygen ions. A single oxygen ion could adsorb onto an iron ion, and therefore, the content of adsorbed oxygen was lower for the film prepared from the solid state reacted powders, which showed larger iron surface coverage. Electrical conductance measurements, performed with increasing temperature in different gaseous environments, confirmed these findings. Higher conductances and lower activation energies were observed for the films with larger samarium surface coverage.
  • H Aono, M Sato, E Traversa, M Sakamoto, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 84 (2) 341 - 347 0002-7820 2001/02 Scientific journal 
    Perovskite-type SmFeO3 powders were prepared by the thermal decomposition of a heteronuclear complex, Sm(Fe(CN)(6)). 4H(2)O and by solid-state reaction between the corresponding single oxides, Sm2O3 and Fe2O3. The thermal decomposition behavior of the complex was studied by thermogravimetric analysis. X-ray diffractometry was used to investigate the structure of the products from the complex thermal decomposition and the formation of SmFeO2 from the oxide mixture. Powders prepared by both methods were used to deposit thick films onto alumina substrates with comb-type gold electrodes. The microstructure and chemical homogeneity of the film surfaces,were investigated by scanning electron microscopy and Auger electron spectroscopy. Thick SmFeO3 single-phase films having a homogeneous elemental distribution on the surface were obtained when powder prepared by thermal decomposition of the complex was used for deposition, even when the powder was fired at low temperature (800 degreesC), Surface chemical analysis was performed by X-ray photoelectron spectroscopy (XPS), The O Is XPS line was deconvoluted into two peaks, attributed to adsorbed oxygen (O-ad) and oxygen in the lattice (O-lattice). Quantitative analysis showed that the surface coverage of iron, expressed as Fe/(Fe + Sm), was larger for the films prepared using the solid-state reacted powder. Although the O-lattice/(Fe + Sm) atomic ratio was not influenced by the processing procedures (and, thus, by iron surface coverage), the amount of O-ad decreased with increasing iron surface coverage, A model of the SmFeO3 surface was used to determine that the outermost layer of the perovskite-type SmFeO3 prepared from the complex consisted mainly of samarium ions that could each bond four adsorbed oxygen ions. A single oxygen ion could adsorb onto an iron ion, and therefore, the content of adsorbed oxygen was lower for the film prepared from the solid state reacted powders, which showed larger iron surface coverage. Electrical conductance measurements, performed with increasing temperature in different gaseous environments, confirmed these findings. Higher conductances and lower activation energies were observed for the films with larger samarium surface coverage.
  • Hiromichi Aono, Masatomi Sakamoto, Yoshihiko Sadaoka
    Journal of the Ceramic Society of Japan 109 (1269) 419 - 424 0914-5400 2001 Scientific journal 
    The thermally decomposed products of the CuRE(dhbaen) (NO3) (dmso)m(H2O)n complex were investigated by differential thermal analysis (TGA), X-ray diffraction patterns (XRD), energy dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). A mixed phase of RE2O2SO4 and CuO was formed at a low temperature. The particle size of CuO in the fixed phase was estimated to be 30-90 nm by XRD. When the ionic radius of RE3+ ion is small, the RE2O2SO4 phase decomposed and formed a heterometallic RE2Cu2O5 at 850-1100°C. It appears that one dmso directly interacted with the RE ion (RE-O = S(-CH3)2) for the complex and the RE-O=S bond remained as RE2O2SO4 after the decomposition, CuO in the mixed phase did not interact with -SO4 which was confirmed by XPS.
  • Hiromichi Aono, Masatomi Sakamoto, Yoshihiko Sadaoka
    Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 109 (1269) 419 - 424 0914-5400 2001 Scientific journal 
    The thermally decomposed products of the CuRE(dhbaen) (NO3) (dmso)m(H2O)n complex were investigated by differential thermal analysis (TGA), X-ray diffraction patterns (XRD), energy dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS). A mixed phase of RE2O2SO4 and CuO was formed at a low temperature. The particle size of CuO in the fixed phase was estimated to be 30-90 nm by XRD. When the ionic radius of RE3+ ion is small, the RE2O2SO4 phase decomposed and formed a heterometallic RE2Cu2O5 at 850-1100°C. It appears that one dmso directly interacted with the RE ion (RE-O = S(-CH3)2) for the complex and the RE-O=S bond remained as RE2O2SO4 after the decomposition, CuO in the mixed phase did not interact with -SO4 which was confirmed by XPS.
  • H Aono, M Sakamoto, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 108 (12) 1052 - 1059 1882-0743 2000/12 [Peer-reviewed]
     Scientific journal 
    A composite material containing La2CuO4 and CuO was directly synthesized by thermal decomposition of a heteronuclear CuLa(dhbaen)(NO3) nH(2)O complex, where dhbaen is N,N'-bis (3-hydroxysalicylidene)-ethylenediamine. The mean particle size was of the order of 200 nm for a sample decomposing at 800 degreesC. The exposure to 7.8 ppm H2S at 50 degreesC for 6 d (the exposure gas was alternately changed from air to 7.8 ppm H2S at 6 h intervals for 6 d) resulted in the formation of copper sulfide and lanthanum sulfate on the surface. At 100 degreesC, the surfaces were mostly covered with both sulfide and sulfate. Lanthanum sulfate and copper sulfide, without copper sulfate, were formed at temperatures below 200 degreesC, Copper sulfate was detected when the sample was exposed at 250 degreesC. For samples exposed at 100 degreesC, the atomic ratio determined by X-ray photoelectron spectroscopy (XPS) for [S (sulfate)]/[La] was 1.6 on the surface and decreased to 0.01 with increasing depth of Ar sputtering on the surface. The ratio of [S (sulfide]/[Cu] was 0.99 on the surface and decreased to about 0.45 upon Ar sputtering, However, [S(sulfate)]/[La] and [S(sulfide)]/[Cu] ratios on the surface were 0.03 and 0.39, respectively, for single-phase La2CuO4 prepared by the solid state reaction method after the exposure. It is concluded that the reactions of Cu and La in La2CuO4 with hydrogen sulfide are accelerated by the presence of well-dispersed CuO.
  • AONO Hiromichi, SAKAMOTO Masatomi, SADAOKA Yoshihiko
    Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 108 (1264) 1052 - 1059 0914-5400 2000/12 
    A composite material containing La_2CuO_4 and CuO was directly synthesized by thermal decomposition of a heteronuclear CuLa(dhbaen)(NO_3)・nH_2O complex, where dhbaen is N, N´-bis(3-hydroxysalicylidene)-ethylenediamine. The mean particle size was of the order of 200 nm for a sample decomposing at 800℃. The exposure to 7.8 ppm H_2S at 50℃ for 6 d (the exposure gas was alternately changed from air to 7.8 ppm H_2S at 6 h intervals for 6 d) resulted in the formation of copper sulfide and lanthanum surface on the surface. At 100℃, the surfaces were mostly covered with both sulfide and sulfate. Lanthanum sulfate and copper sulfide, without copper sulfate, were formed at temperatures below 200℃. Copper sulfate was detected when the sample was exposed at 250℃. For samples exposed at 100℃, the atomic ratio determined by X-ray photoelectron spectroscopy (XPS) for [S(sulfate)]/[La] was 1.6 on the surface and decreased to 0.01 with increasing depth of Ar sputtering on the surface. The ratio of [S(sulfide)]/[Cu] was 0.99 on the surface and decreased to about 0.45 upon Ar sputtering. However, [S(sulfate)]/[La] and [S(sulfide)]/[Cu] ratios on the surface were 0.03 and 0.39, respectively, for single-phase La_2CuO_4 prepared by the solid state reaction method after the exposure. It is concluded that the reactions of Cu and La in La_2CuO_4 with hydrogen sulfide are accelerated by the presence of well-dispersed CuO.
  • Hiromichi Aono, Masatomi Sakamoto, Yoshihiko Sadaoka
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 108 1052 - 1059 0914-5400 2000/12 
    A composite material containing La 2CuO 4 and CuO was directly synthesized by thermal decomposition of a heteronuclear CuLa(dhbaen)(NO 3) -nH 2O complex, where dhbaen is N,N′-bis(3-hydroxysalicylidene)-ethylenediamine. The mean particle size was of the order of 200 nm for a sample decomposing at 800°C. The exposure to 7.8 ppm H 2S at 50°C for 6 d (the exposure gas was alternately changed from air to 7.8 ppm H 2S at 6 h intervals for 6 d) resulted in the formation of copper sulfide and lanthanum sulfate on the surface. At 100°C, the surfaces were mostly covered with both sulfide and sulfate. Lanthanum sulfate and copper sulfide, without copper sulfate, were formed at temperatures below 200°C. Copper sulfate was detected when the sample was exposed at 250°C. For samples exposed at 100°C, the atomic ratio determined by X-ray photoelectron spectroscopy (XPS) for [S (sulfate)]/[La] was 1.6 on the surface and decreased to 0.01 with increasing depth of Ar sputtering on the surface. The ratio of [S (sulfide)]/[Cu] was 0.99 on the surface and decreased to about 0.45 upon Ar sputtering. However, [S(sulfate)]/[La] and [S(sulfide)]/[Cu] ratios on the surface were 0.03 and 0.39, respectively, for single-phase La 2CuO 4 prepared by the solid state reaction method after the exposure. It is concluded that the reactions of Cu and La in La 2CuO 4 with hydrogen sulfide are accelerated by the presence of well-dispersed CuO.
  • E Di Bartolomeo, E Traversa, L Montanaro, H Aono, Y Sadaoka
    JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 19 (1-3) 181 - 185 0928-0707 2000/12 Scientific journal 
    Sol-gel processed NASICON-type with new compositions in the Na3Zr2-(x/4)Si2-xP1+xO12 system showed an improved sinterability with an increase in the x value. This is attributed to liquid phase sintering. This dense electrolyte system is suitable for the application as gas sensors. The CO2 gas sensors using highly dense x = 0.667 (sample B) and x = 1.333 (sample C) samples show a stable EMF response in dry atmosphere which is very close to the theoretical value. Although a lower sensitivity and slower response were obtained in humid CO2 gas, the sensor performance recovered after switching from humid gas to dry gas.
  • Hiromichi Aono, Junji Ohmori, Yoshihiko Sadaoka
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 108 892 - 897 0914-5400 2000/12 
    Perovskite-type LaFeO 3 powders were prepared by thermal decomposition of a heteronuclear complex, La[Fe(CN) 6]·4H 2O at 700°C. Powders were deposited as thick films on alumina substrates with comb-type Au electrodes and then sintered in nitrogen or air atmosphere. The surface chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The O1s XPS line was separated in two peaks attributed to adsorbed oxygen (O ad) and oxygen in the lattice (O lattice) on the surface. The ratio [O ad + O lattice]/[La + Fe] was uninfluenced by the ambient during sintering. The [O lattice]/[La+Fe] atomic ratio decreased and [O ad]/[La+Fe] value increased upon sintering in N 2 atmosphere, as compared with samples sintered in air. It was argued that O ad sites act as adsorption sites for nitrogen dioxide. The increase in O ad sites is effective for enhancing electrical conductivity in nitrogen dioxide.
  • E Traversa, L Montanaro, H Aono, Y Sadaoka
    JOURNAL OF ELECTROCERAMICS 5 (3) 261 - 272 1385-3449 2000/11 Scientific journal 
    Powders and pellets of new NASICON compositions have been synthesized using a mixed inorganic-organic sol-gel synthesis, by the preliminary formation of a pre-hydrolized TEOS xerogel. The investigated compositions can be described by the general formula Na3Zr2-(x/4)Si2-xP1+xO12, obtained by keeping the Na concentration constant (= 3) at the optimum value reported for ionic conductivity, with x = 0 (the usual NASICON composition), 0.667, and 1.333. The xerogels were calcined at various temperatures in the range 400-1200 degreesC. The powder samples were analyzed by TG/DTA, BET measurements, XRD, and SEM. The powders calcined at 500 degreesC were sintered into pellets at 1100 degreesC for 6 h. The sintering behavior of the pellets was investigated by dilatometric measurements and SEM observations. The sinterability increased with increasing x value. Dense samples of the new compositions were obtained by sintering at only 1100 degreesC. This is attributed to the occurrence of liquid phase sintering. The electrical conductivity of the NASICON sintered bodies was measured by ac impedance spectroscopy. The conductivity decreased with decreasing c(0) lattice parameter of the hexagonal structure or increasing x value. The CO2 gas sensors, using as electrolyte the dense samples of the new NASICON compositions, showed good EMF response that was very close to the theoretical value, even for the sample with x = 1.333 that showed much lower conductivity.
  • H Aono, Y Sadaoka
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 147 (11) 4363 - 4367 0013-4651 2000/11 Scientific journal 
    A composite Na+ conductor of polycrystalline NASICON mixed with glassy Na2O-Al2O3-4SiO(2) (40 wt%) was investigated and used for a Cl-2 gas sensor. The densification of the solid electrolyte was improved by the addition of the glassy material. The sensor probe using the composite electrolyte and RuO2 + NaCl (1:1) measuring electrode produced a rapid electromotive force (EMF) change for the Cl-2 gas concentration below 10 ppm at above 450 degreesC. For the low temperature of 400 degreesC, a slow EMF response was obtained due to the side reaction between the Cl-2, gas and Na2O on the solid electrolyte and/or slow Cl-2, reduction to Cl- ion on the electrode. This sensor EMF value in air was only slightly influenced by the changing of the O-2 or CO2 gas concentration. (C) 2000 The Electrochemical Society. S0013-4651(00)04-083-0. All nights reserved.
  • H Aono, J Ohmori, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 108 (10) 892 - 897 1882-0743 2000/10 Scientific journal 
    Perovskite-type LaFeO3 powders were prepared by thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)]. 4H(2)O at 700 degreesC. Powders were deposited as thick films on alumina substrates with comb-type Au electrodes and then sintered in nitrogen or air atmosphere. The surface chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The Ols XPS line was separated in two peaks attributed to adsorbed oxygen (O-ad) and oxygen in the lattice (O-lattice) on the surface. The ratio [O-ad + O-lattice]/[La + Fe] was uninfluenced by the ambient during sintering. The [O-lattice]/[La + Fe] atomic ratio decreased and [O-ad]/ [La + Fe] value increased upon sintering in N-2 atmosphere, as compared with samples sintered in air. It was argued that O-ad sites act as adsorption sites for nitrogen dioxide. The increase in O-ad sites is effective for enhancing electrical conductivity in nitrogen dioxide.
  • AONO Hiromichi, OHMORI Junji, SADAOKA Yoshihiko
    Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 108 (1262) 892 - 897 0914-5400 2000/10 
    Perovskite-type LaFeO_3 powders were prepared by thermal decomposition of a heteronuclear complex, La[Fe(CN)_6]・4H_2O at 700℃. Powders were deposited as thick films on alumina substrates with comb-type Au electrodes and then sintered in nitrogen or air atmosphere. The surface chemical analysis was performed using X-ray photoelectron spectroscopy (XPS). The O1s XPS line was separated in two peaks attributed to adsorbed oxygen (O_<ad>) and oxygen in the lattice (O_<lattice>) on the surface. The ratio [O_<ad>+O_<lattice>]/[La+Fe] was uninfluenced by the ambient during sintering. The [O_<lattice>]/[La+Fe] atomic ratio decreased and [O_<ad>]/[La+Fe] value increased upon sintering in N_2 atmosphere, as compared with samples sintered in air. It was argued that O_<ad> sites act as adsorption sites for nitrogen dioxide. The increase in O_<ad> sites is effective for enhancing electrical conductivity in nitrogen dioxide.
  • E Traversa, H Aono, Y Sadaoka, L Montanaro
    SENSORS AND ACTUATORS B-CHEMICAL 65 (1-3) 204 - 208 0925-4005 2000/06 Scientific journal 
    High-conductivity and high-density samples with new compositions in the NASICON-type electrolyte series, i.e., the Na(3)Zr(2-(x/4))Si(2-x)P(1+x)O(12) system, with x = 0(A), 0.667(B), and 1.333(C) were synthesized using a mixed inorganic-organic sol-gel process. The sinterability was improved with increasing the x value, but the conductivity decreased. Highly dense samples were obtained by sintering at 1100 degrees C. The conductivity decreased with decreasing the c lattice parameter of the hexagonal structure. Nevertheless, the CO(2) gas sensors using the highly dense B and C samples showed good EMF response which is very close to the theoretical value. (C) 2000 Elsevier Science S.A. All rights reserved.
  • E Traversa, P Nunziante, L Sangaletti, B Allieri, LE Depero, H Aono, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 83 (5) 1087 - 1092 0002-7820 2000/05 Scientific journal 
    Ultrafine powders of trimetallic orthoferrites containing lanthanum and samarium in various ratios were synthesized by thermal decomposition at low temperatures of the corresponding hexacyano complexes to modulate the functional properties of these perovskite-type oxides. The precursors and their decomposition products were analyzed by simultaneous thermogravimetric and differential thermal analyses, X-ray diffractometry, and Raman spectroscopy. Single-phase trimetallic precursors and oxides were obtained. The crystal structure of the perovskite-type oxides was orthorhombic, and the lattice parameters were affected by the ionic size of the rare-earth elements present in the oxides. Raman spectra showed a broadening of the vibrational bands with increased lanthanum content, This was ascribed to some disorder in the oxygen sublattice, related to distortions of the cation-oxygen coordination, and to a reduction of the orthorhombic distortion in the unit-cell basal plane. Most of the Raman modes above 200 cm(-1), associated with the vibration of oxygen ions, showed a frequency increase with effective cation mass, defined as m(eff) = xm(La) + (1 - x)m(Sm), i.e., with samarium content, This was explained by assuming that the force constants increased with decreased Ln-O and Fe-O interatomic distances observed for high samarium content.
  • Hiromichi AONO, Masatomi SAKAMOTO, Yoshihiko SADAOKA
    J. Ceram. Soc. Jpn. 108 (1264) 1052 - 1059 0914-5400 2000
  • Synthesis and Characterization of Trimetallic Rare Earth Orthoferrites,LaxSm1-xFeO3.
    The Korean Journal of Ceramics 6 (1) 21 - 26 2000
  • H Aono, Y Sadaoka
    CHEMISTRY LETTERS 2000 (1) 34 - 35 0366-7022 2000/01 Scientific journal 
    A composite Na+ conductor of polycrystalline NASICON mixed with a glassy Na2O-Al2O3-4SiO(2) (40wt%) was used in Cl-2 gas sensor. The probe using the composite electrolyte and a RuO2+NaCl (1:1) measuring electrode gave rapid EMF changes even for sub-ppm level of Cl-2 gas concentration (below 6 ppm).
  • Surface characterization of La2CuO4 and CuO composite treated with H2S at ppm levels, Meeting Abstracts
    Proc. of the 198th Meeting of The Elctrochemical Society 467 - 475 2000
  • Enrico Traversa, Patrizia Nunziante, Luigi Sangaletti, Brigida Allieri, Laura E. Depero, Hiromichi Aono, Yoshihiko Sadaoka
    Journal of the American Ceramic Society 83 1087 - 1092 0002-7820 2000/01 
    Ultrafine powders of trimetallic orthoferrites containing lanthanum and samarium in various ratios were synthesized by thermal decomposition at low temperatures of the corresponding hexacyano complexes to modulate the functional properties of these perovskite-type oxides. The precursors and their decomposition products were analyzed by simultaneous thermogravimetric and differential thermal analyses, X-ray diffractometry, and Raman spectroscopy. Single-phase trimetallic precursors and oxides were obtained. The crystal structure of the perovskite-type oxides was orthorhombic, and the lattice parameters were affected by the ionic size of the rare-earth elements present in the oxides. Raman spectra showed a broadening of the vibrational bands with increased lanthanum content. This was ascribed to some disorder in the oxygen sublattice, related to distortions of the cation-oxygen coordination, and to a reduction of the orthorhombic distortion in the unit-cell basal plane. Most of the Raman modes above 200 cm-1, associated with the vibration of oxygen ions, showed a frequency increase with effective cation mass, defined as meff = xmLa + (1 - x) mSm, i.e., with samarium content. This was explained by assuming that the force constants increased with decreased Ln-O and Fe-O interatomic distances observed for high samarium content.
  • Hiromichi Aono, Yoshihiko Sadaoka
    Chemistry Letters (1) 34 - 35 0366-7022 2000 Scientific journal 
    A composite Na+ conductor of polycrystalline NASICON mixed with a glassy Na2O-Al2O3-4SiO2 (40wt%) was used in Cl2, gas sensor. The probe using the composite electrolyte and a RuO2+NaCl (1:1) measuring electrode gave rapid EMF changes even for sub-ppm level of Cl2 gas concentration (below 6 ppm).
  • H Aono, M Tsuzaki, A Kawaura, M Sakamoto, E Traversa, Y Sadaoka
    CHEMISTRY LETTERS (11) 1175 - 1176 0366-7022 1999/11 Scientific journal 
    The heteronuclear LaMn(dhbaen)(OH)(NO3)(H2O), complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at 700 degrees C. Particle size of the samples decomposed at 600 degrees C and 700 degrees C is ca. 20 nm and 50 nm, respectively.
  • E Traversa, S Villanti, G Gusmano, H Aono, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 82 (9) 2442 - 2450 0002-7820 1999/09 Scientific journal 
    Ultrafine SmFeO(3) powders were prepared by the thermal decomposition at 700 degrees C of the corresponding hexacyanocomplex, Sm[Fe(CN)(6)]. 4H(2)O. These powders were used for the preparation of pastes which were deposited as thick films on alumina substrates with comb-type Au electrodes. The films were fired at different temperatures in the 800-1000 degrees C range. The content of alpha-terpineol, a component of the organic vehicle, was varied in the range 0.0046-4 wt%, The microstructure, the chemical composition at the surface, the electrical conductivity, and the NO(2) sensing properties of the films were investigated. The content of alpha-terpineol strongly influenced the electrical conductivity and its activation energy, A significant reduction in the NO(2) response was observed for the films containing smaller amounts of alpha-terpineol, together with an increase in conductivity. On the other hand, the largest NO(2) response was observed for the films fired at 1000 degrees C when 4 wt% of alpha-terpineol was used. Such increase in conductivity is attributed to a different oxygen surface layer on the SmFeO(3) surface, which is induced by the decomposition reaction of alpha-terpineol during sintering, The materials processing parameters are thus of primary concern for the NO(2) sensing properties of the SmFeO(3) thick films. The correlations found between activation energy, NO(2) sensitivity, and materials characteristics (influenced by the preparation parameters) are reported. These correlations can be used to design the gas-sensing properties of SmFeO(3) thick films for the optimization of their sensing characteristics.
  • E Traversa, S Villanti, G Gusmano, H Aono, Y Sadaoka
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 82 (9) 2442 - 2450 0002-7820 1999/09 Scientific journal 
    Ultrafine SmFeO(3) powders were prepared by the thermal decomposition at 700 degrees C of the corresponding hexacyanocomplex, Sm[Fe(CN)(6)]. 4H(2)O. These powders were used for the preparation of pastes which were deposited as thick films on alumina substrates with comb-type Au electrodes. The films were fired at different temperatures in the 800-1000 degrees C range. The content of alpha-terpineol, a component of the organic vehicle, was varied in the range 0.0046-4 wt%, The microstructure, the chemical composition at the surface, the electrical conductivity, and the NO(2) sensing properties of the films were investigated. The content of alpha-terpineol strongly influenced the electrical conductivity and its activation energy, A significant reduction in the NO(2) response was observed for the films containing smaller amounts of alpha-terpineol, together with an increase in conductivity. On the other hand, the largest NO(2) response was observed for the films fired at 1000 degrees C when 4 wt% of alpha-terpineol was used. Such increase in conductivity is attributed to a different oxygen surface layer on the SmFeO(3) surface, which is induced by the decomposition reaction of alpha-terpineol during sintering, The materials processing parameters are thus of primary concern for the NO(2) sensing properties of the SmFeO(3) thick films. The correlations found between activation energy, NO(2) sensitivity, and materials characteristics (influenced by the preparation parameters) are reported. These correlations can be used to design the gas-sensing properties of SmFeO(3) thick films for the optimization of their sensing characteristics.
  • E Hasegawa, H Aono, T Igoshi, M Sakamoto, E Traversa, Y Sadaoka
    JOURNAL OF ALLOYS AND COMPOUNDS 287 (1-2) 150 - 158 0925-8388 1999/06 Scientific journal 
    YBa2Cu3O7-delta powders were prepared by the thermal decomposition of a heteronuclear complex, CuY1/3Ba2/3(dhbaen)(NO3)(1/3)(H2O)(3). The products of the complex thermal decomposition were analyzed by TG-DTA, XRD, SEM-Auger and XPS. The decomposition of the CuY1/3Ba2/3-complex was obtained at about 500 degrees C and the product was a mixture of oxides and carbonates. The formation of YBa2Cu3O7-delta proceeded at 800 degrees C, with a gradual decomposition of the carbonates. A homogeneous distribution of each element, Y, Ba and Cu, was observed for the decomposed CuY1/3Ba2/3-complex by SEM-Auger analysis. The binding energy values of Ba-3d5/2 and O1s photolines from Ba and O in the superconductive lattice did not shift during the sputtering period. Furthermore, the formation of Ba rich regions on the surface was depressed by using the complex as a starting material for homogeneous 123-oxide, YBa2Cu3O7-delta. (C) 1999 Elsevier Science S.A. All rights reserved.
  • 杉本 栄佑, 中山 享, 青野 宏通
    新居浜工業高等専門学校紀要 新居浜工業高等専門学校 (35) 55 - 62 1342-6540 1999/01
  • Hiromichi Aono, Miyoko Tsuzaki, Akihiro Kawaura, Masatomi Sakamoto, Enrico Traversa, Yoshihiko Sadaoka
    Chemistry Letters (11) 1175 - 1176 0366-7022 1999 Scientific journal 
    The heteronuclear LaMn(dhbacn)(OH)(NO3)(H2O)4 complex was synthesized and perovskite-type hexagonal LaMnO3 was obtained by its thermal decomposition at 700 °C. Particle size of the samples decomposed at 600 °C and 700 °C is ca. 20 nm and 50 nm, respectively.
  • H Aono, K Kinoshita, M Sakamoto, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 106 (10) 958 - 963 1882-0743 1998/10 Scientific journal 
    NdFe0.5C0.5O3, a trimetallic perovskite-type oxide, was prepared by thermal decomposition of a synthesized heteronuclear complex of Nd[Fe0.5Co0.5(CN)6]. 4H(2)O. Using XRD, the perovskite-type phase was detected in the sample heated at 500 degrees C and the complex was completely decomposed to NdFe0.5Co0.5O8 at 700 degrees C. Distribution of the elements Nd, Fe, and Co on the surface of the complex that decomposed at 800 degrees C were homogeneous according to Auger electron spectroscopy (AES) analysis, For a solid-state reaction method using a mixture of single oxides (Nd2O3, Fe2O3 and CoO), a high heating temperature (>1000 degrees C) is needed to form a single phase of the perovskite-type oxide. Fe-rich and Go-rich regions on the surface were clearly detected even in a mixture calcined at 1100 degrees C. Surface concentration and structure of samples obtained by both methods were investigated by X-ray photoelectron spectroscopy (XPS). For both samples, XPS revealed that the (Fe + Co)/Nd ratio was less than unity.
  • AONO Hiromichi, KINOSHITA Kouichi, SAKAMOTO Masatomi, SADAOKA Yoshihiko
    Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 106 (1238) 958 - 963 0914-5400 1998/10 
    NdFe_<0.5>Co_<0.5>O_3, a trimetallic perovskite-type oxide, was prepared by thermal decomposition of a synthesized heteronuclear complex of Nd[Fe_<0.5>Co_<0.5>(CN)_6]・4H_2O. Using XRD, the perovskite-type phase was detected in the sample heated at 500℃ and the complex was completely decomposed to NdFe_<0.5>Co_<0.5>O_3 at 700℃. Distribution of the elements Nd, Fe, and Co on the surface of the complex that decomposed at 800℃ were homogeneous according to Auger electron spectroscopy(AES) analysis. For a solid-state reaction method using a mixture of single oxides(Nd_2O_3, Fe_2O_3 and CoO), a high heating temperature(>1000℃)is needed to form a single phase of the perovskite-type oxide. Fe-rich and Co-rich regions on the surface were clearly detected even in a mixture calcined at 1100℃. Surface concentration and structure of samples obtained by both methods were investigated by X-ray photoelectron spectroscopy(XPS). For both samples, XPS revealed that the(Fe+Co)/Nd ratio was less than unity.
  • Hiromichi Aono, Kouichi Kinoshita, Masatomi Sakamoto, Yoshihiko Sadaoka
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 106 958 - 963 0914-5400 1998/10 
    NdFe0.5Co0.5O3, a trimetallic perovskite-type oxide, was prepared by thermal decomposition of a synthesized heteronuclear complex of Nd[Fe0.5Co0.5(CN)6]·4H2O. Using XRD, the perovskite-type phase was detected in the sample heated at 500°C and the complex was completely decomposed to NdFe0.5Co0.5O3 at 700°C. Distribution of the elements Nd, Fe, and Co on the surface of the complex that decomposed at 800°C were homogeneous according to Auger electron spectroscopy (AES) analysis. For a solid-state reaction method using a mixture of single oxides (Nd2O3, Fe2O3 and CoO), a high heating temperature ( > 1000°C) is needed to form a single phase of the perovskite-type oxide. Fe-rich and Co-rich regions on the surface were clearly detected even in a mixture calcined at 1000°C. Surface concentration and structure of samples obtained by both methods were investigated by X-ray photoelectron spectroscopy (XPS). For both samples, XPS revealed that the (Fe+Co)/Nd ratio was less than unity.
  • H Aono, H Supriyatno, Y Sadaoka
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 145 (9) 2981 - 2984 0013-4651 1998/09 Scientific journal 
    A CO2 gas sensor using a combined solid electrolyte of a Na+ conducting Na2O-Al2O3-4SiO(2) glass and an yttria-stabilized zirconia was prepared, and its sensing properties in dry and wet gases were investigated using a variable flow rate of the test gases. The glassy electrolyte in the sensor was suitable as a CO2 sensing material because of its high density and good contact between the electrolytes. In a dry atmosphere, excellent results were obtained for the CO2 gas concentration dependence of the electromotive force (EMF), expressed by EMF (mV) = 547.5 - 74.0 log [C-CO2/ppm] at 470 degrees C in which the sensitivity of 74.0 mV/decade was in fair agreement with the theoretical value based on a two-electron electrochemical reaction. In the case of wet CO2 gas, the sensitivities and response time were depressed even for a high CO2 gas concentration. The decomposition of Na2CO3 into sodium oxide on the Pt electrode was accelerated in the presence of H2O. The reason for the depression of the sensing properties in a humid condition could be ascribed to its reformation reaction as a side reaction.
  • H Aono, H Supriyatno, Y Sadaoka
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 145 (9) 2981 - 2984 0013-4651 1998/09 Scientific journal 
    A CO2 gas sensor using a combined solid electrolyte of a Na+ conducting Na2O-Al2O3-4SiO(2) glass and an yttria-stabilized zirconia was prepared, and its sensing properties in dry and wet gases were investigated using a variable flow rate of the test gases. The glassy electrolyte in the sensor was suitable as a CO2 sensing material because of its high density and good contact between the electrolytes. In a dry atmosphere, excellent results were obtained for the CO2 gas concentration dependence of the electromotive force (EMF), expressed by EMF (mV) = 547.5 - 74.0 log [C-CO2/ppm] at 470 degrees C in which the sensitivity of 74.0 mV/decade was in fair agreement with the theoretical value based on a two-electron electrochemical reaction. In the case of wet CO2 gas, the sensitivities and response time were depressed even for a high CO2 gas concentration. The decomposition of Na2CO3 into sodium oxide on the Pt electrode was accelerated in the presence of H2O. The reason for the depression of the sensing properties in a humid condition could be ascribed to its reformation reaction as a side reaction.
  • Y Sadaoka, H Aono, E Traversa, M Sakamoto
    JOURNAL OF ALLOYS AND COMPOUNDS 278 (1-2) 135 - 141 0925-8388 1998/08 Scientific journal 
    The thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)]. nH(2)O, leads to the preparation of nanosized perovskite-type LaFeO3 powders. The exothermic decomposition of the cyanide groups at 300 degrees C, starting abruptly and the formation of LaFeO3 without the presence of single oxides such as La2O3 and Fe2O3 were observed. The formation of LaFeO3 from the complex involves the formation of carbonates and nitrates, which facilitate the formation of nanosized LaFeO3 powders. Concomitantly formed carbonate and nitrate decomposed gradually and the specific surface area of nanosized LaFeO3 increased up to 38 m(2) g(-1) at 350 degrees C. (C) 1998 Elsevier Science S.A. All rights reserved.
  • Y Sadaoka, H Aono, E Traversa, M Sakamoto
    JOURNAL OF ALLOYS AND COMPOUNDS 278 (1-2) 135 - 141 0925-8388 1998/08 Scientific journal 
    The thermal decomposition of a heteronuclear complex, La[Fe(CN)(6)]. nH(2)O, leads to the preparation of nanosized perovskite-type LaFeO3 powders. The exothermic decomposition of the cyanide groups at 300 degrees C, starting abruptly and the formation of LaFeO3 without the presence of single oxides such as La2O3 and Fe2O3 were observed. The formation of LaFeO3 from the complex involves the formation of carbonates and nitrates, which facilitate the formation of nanosized LaFeO3 powders. Concomitantly formed carbonate and nitrate decomposed gradually and the specific surface area of nanosized LaFeO3 increased up to 38 m(2) g(-1) at 350 degrees C. (C) 1998 Elsevier Science S.A. All rights reserved.
  • H Aono, E Sugimoto, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 106 (7) 645 - 649 1882-0743 1998/07 Scientific journal 
    PbX2-PbO-SiO2 (X=Cl, Br and I) glasses were prepared and their electrical properties were investigated. The sole carrier for these glasses is the X- ion, which was estimated from the EMF (electromotive force) of the X-2 gas concentration cell and the electrical properties. The ionic conductivity was enhanced with a decrease in ionic radius and increase in content of the X- ion in the glasses. The conductivities for the glass plates are about one order of magnitude higher than those for the pellets prepared from glass powder. For the X=I system, a maximum conductivity of 4.5 x 10(-7) S cm(-1) at 373 K was obtained for the composition 0.59PbI(2) 0.31PbO 0.10SiO(2). The glass formation region was determined for the PbI2-PbO-SiO2 system.
  • Hiromichi Aono, Eisuke Sugimoto, Yoshihiko Sadaoka
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 106 645 - 649 0914-5400 1998/07 
    PbX2-PbO-SiO2 (X=Cl, Br and I) glasses were prepared and their electrical properties were investigated. The sole carrier for these glasses is the X- ion, which was estimated from the EMF (electromotive force) of the X2 gas concentration cell and the electrical properties. The ionic conductivity was enhanced with a decrease in ionic radius and increase in content of the X- ion in the glasses. The conductivities for the glass plates are about one order of magnitude higher than those for the pellets prepared from glass powder. For the X=I system, a maximum conductivity of 4.5 × 10-7 S·cm-1 at 373 K was obtained for the composition 0.59PbI2·0.31PbO·0.10SiO2. The glass formation region was determined for the PbI2-PbO-SiO2 system.
  • S Matsushima, M Sakamoto, H Aono, Y Sadaoka
    SOLID STATE IONICS 108 (1-4) 31 - 36 0167-2738 1998/05 Scientific journal 
    Heteronuclear complexes Ln[FexCo1-x(CN)(6)]4H(2)O (Ln = Pr-Yb) were synthesized and the crystal structures of thermally decomposed complexes were investigated. For Ln = Pr-Gd, only perovskite-type oxides (crystal system: orthorhombic) were formed even when the complexes decomposed at 800 degrees C. The lattice constants (a, b and c) of the oxides increased linearly with increasing Fe/Co ratio. On the other hand, for Ln = Dy-Yb, the Ln(2)O(3) phase was obtained as the major product, especially for lower Fe content. The single phase of the perovskite-type oxide could not be obtained even for x = 1, although the diffraction peaks due to the perovskite structure gradually increased with increasing Fe content. (C) 1998 Elsevier Science B.V. All rights reserved.
  • H Aono, Y Sadaoka, E Traversa, L Montanaro
    TECHNICAL DIGEST OF THE SEVENTH INTERNATIONAL MEETING ON CHEMICAL SENSORS 72 - 74 1998 [Peer-reviewed]
     International conference proceedings 
    High-conductivity and high-density samples in the NASICON-type electrolyte series, i.e., the Na(3)Z(2-(x/4))Si2-xP1+xO12 system, with x = 0(A), 0.667(B), and 1.333(C) were synthesized using a sol-gel process. The sinterability was improved with increasing the x value, but the conductivity decreased. The CO2 gas sensors using the highly dense B and C samples show good EMF response which is very close to the theoretical value.
  • AONO Hiromichi, SADAOKA Yoshihiko
    Bulletin of the Society of Sea Water Science, Japan 日本海水学会 52 (1) 41 - 44 0369-4550 1998
  • ガスセンサ2
    青野宏通, 定岡芳彦
    日本海水学会誌 1 (1) 41 - 45 1998/01 [Peer-reviewed]
     Research society
  • E Traversa, L Montanaro, H Aono, Y Sadaoka
    SOL-GEL SYNTHESIS AND PROCESSING 95 225 - 234 1042-1122 1998 International conference proceedings 
    Powders and pellets of new NASICON compositions have been synthesized using a mixed inorganic-organic sol-gel synthesis, by the preliminary formation of a pre-hydrolized TEOS xerogel. The investigated compositions can be described by the general formula Na3Zr2-(x/4)Si2-xP1+xO12 obtained by keeping constant (= 3) the Na concentration at the optimum value reported for ionic conductivity, with x = 0 (the usual NASICON composition), 0.667, and 1.333. The xerogels were calcined at various temperatures in the range 400-800 degrees C. The samples were analyzed by TG/DTA, BET measurements, XRD, EDS, and SEM. The powders were sintered into pellets at 1100 degrees C. The sinterability increased with increasing the x value. This is attributed to the presence of a glassy phase and the occurrence of liquid phase sintering. The electrical conductivity of the NASICON sintered bodies, measured by a.c. impedance spectroscopy, is correlated with the lattice parameters of the hexagonal structure, and increased with increasing the x value.
  • 杉本 栄佑, 青野 宏通, 尾西 康次
    新居浜工業高等専門学校紀要 新居浜工業高等専門学校 (34) 88 - 95 1342-6540 1998/01
  • AONO Hiromichi, SADAOKA Yoshihiko
    Bulletin of the Society of Sea Water Science, Japan 日本海水学会 51 (6) 395 - 398 0369-4550 1997/12
  • Masatomi Sakamoto, Patrizia Nunziante, Enrico Traversa, Shigenori Matsushima, Masanari Miwa, Hiromichi Aono, Yoshihiko Sadaoka
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 105 963 - 969 0914-5400 1997/11 Scientific journal 
    Heteronuclear complexes of Ln[FexCo1-x(CN)6]·4H 2O(Ln=Pr-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800°C. The lattice parameters, a-, b- and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln2O3 phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln3+ ion and the T3+ ion (T = Fe or Co).
  • M Sakamoto, P Nunziante, E Traversa, S Matsushima, M Miwa, H Aono, Y Sadaoka
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 105 (11) 963 - 969 1882-0743 1997/11 Scientific journal 
    Heteronuclear complexes of Ln[FexCo1-x(CN)(6)].4H(2)O(Ln=PT-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800 degrees C. The lattice parameters, a-, b-and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln(2)O(3) phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln(3+) ion and the T3+ ion (T=Fe or Co).
  • SAKAMOTO Masatomi, NUNZIANTE Patrizia, TRAVERSA Enrico, MATSUSHIMA Shigenori, MIWA Masanari, AONO Hiromichi, SADAOKA Yoshihiko
    Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 105 (1227) 963 - 969 0914-5400 1997/11 
    Heteronuclear complexes of Ln[Fe_xCo_<1-x>(CN)_6]・4H_2O (Ln=Pr-Yb) were synthesized and their thermal decomposition products were investigated. Thermal decomposition of the complexes results in the formation of perovskite-type oxides for Ln=Pr-Gd even at 800℃. The lattice parameters, a-, b- and c-lattice constants (crystal system: orthorhombic) increase linearly with the ratio of Fe/Co for the perovskite-type oxide. For Ln=Dy through Yb, the Ln_2O_3 phase is observed as the major product for x=0, but its content decreased with an increase in the Fe content; however, a single phase of the perovskite-type oxide was not formed for x=1. The perovskite-type structure for the Fe systems is easier to form compared with the Co systems. We clarified that the formation of the perovskite-type oxide is mainly affected by the ionic radius of the Ln^<3+> ion and the T^<3+> ion (T=Fe or Co).
  • M Sakamoto, T Igoshi, M Sato, S Matsushima, M Miwa, H Aono, Y Sadaoka
    JOURNAL OF ALLOYS AND COMPOUNDS 260 (1-2) 59 - 63 0925-8388 1997/09 Scientific journal 
    To facilitate the preparation of finer and more homogeneous CuREOx and to achieve a lowering of the formation temperature, heteronuclear CuRE(1:1) complexes, CuRE(dhbaen)(NO3). nH(2)O were synthesized as precursor. As it was expected for RE=La through Gd, only a mixture of CuO and CuRE2O4 was formed even when the complex decomposed at 800 degrees C since the Cu/RE ratio is 1. For RE=Y and Tb through Lu, Cu2RE2O5 was formed by way of CuO and RE2O3. The structure of the decomposed product is controlled by the coordination number and ionic size of RE ion. The minimum radius ratio for eightfold coordination of RE3+ ion suggests that preparation of homogeneous Cu:RE(1:1) oxide with Cu2Ho2O5 type structure is difficult for RE=La through Gd. (C) 1997 Elsevier Science S.A.
  • M Sakamoto, T Igoshi, M Sato, S Matsushima, M Miwa, H Aono, Y Sadaoka
    JOURNAL OF ALLOYS AND COMPOUNDS 260 (1-2) 59 - 63 0925-8388 1997/09 Scientific journal 
    To facilitate the preparation of finer and more homogeneous CuREOx and to achieve a lowering of the formation temperature, heteronuclear CuRE(1:1) complexes, CuRE(dhbaen)(NO3). nH(2)O were synthesized as precursor. As it was expected for RE=La through Gd, only a mixture of CuO and CuRE2O4 was formed even when the complex decomposed at 800 degrees C since the Cu/RE ratio is 1. For RE=Y and Tb through Lu, Cu2RE2O5 was formed by way of CuO and RE2O3. The structure of the decomposed product is controlled by the coordination number and ionic size of RE ion. The minimum radius ratio for eightfold coordination of RE3+ ion suggests that preparation of homogeneous Cu:RE(1:1) oxide with Cu2Ho2O5 type structure is difficult for RE=La through Gd. (C) 1997 Elsevier Science S.A.
  • 青野宏通, 定岡芳彦
    日本海水学会誌 (6) 395 - 98 1997/06 [Invited]
     Research society
  • H Aono, A Yamabayashi, E Sugimoto, Y Mori, Y Sadaoka
    SENSORS AND ACTUATORS B-CHEMICAL 40 (1) 7 - 13 0925-4005 1997/05 Scientific journal 
    The effects of BaO contamination on the behaviour of a Cl-2 gas sensor using a 0.97BaCl(2)-0.03KCl solid electrolyte have been investigated. The addition of BaO to the electrolyte is found to produce unfavourable effects on both the measuring and reference electrodes through a side reaction such as BaO + Cl-2 --> BaCl2 + (1/2)O-2. The presence of BaO in the vicinity of the measuring electrode results in decreases in the e.m.f. and rate of response, especially when the Cl-2 gas concentration is lowered to a few tens of ppm. Its presence near to the reference electrode, on the other hand, results in the upward deviation of the e.m.f. over the entire range of Cl-2 concentration. The probe prepared in vacuo, free of such BaO contamination, gives e.m.f. values in good agreement with the theoretical ones for Cl-2 gas concentrations between 10 and 1000 ppm, In contrast, the probe prepared in air shows a slower response as well as a more extensive deviation from theory in the low Cl-2 concentration range, suggesting that the electrolyte near the measuring electrode is contaminated with BaO.
  • The Influence of Wet Condition for Electrochemical CO2 Gas Sensor Using Sodium Ionic Conductor
    Proc. of The 3rd East Asian Conference on Chemical Sensors 110 - 113 1997
  • Optical Properties of TPPH2 Derivatives and its Application to HCl Gas Sensor
    Proc. of The 3rd East Asian Conference on Chemical Sensors 122 - 125 1997
  • NO2 Gas Detection Using SmFeO3 Thick Films
    Proc. of The 3rd East Asian Conference on Chemical Sensors 154 - 157 1997
  • Hiromichi Aono, Eisuke Sugimoto
    Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan 104 235 - 238 0914-5400 1996/12 
    A glassy solid electrolyte of the (1-x)PbI2-xPbO system was prepared using two kinds of quenching methods. In the case of the iron pressing method, 0.68PbI2-0.32PbO (x=0.32) glass was obtained when PbI2 melt reacts with oxygen in air. In the case of the quenching method using ice water, the glassy sample was not obtained when x<0.35. Conductivity was enhanced and crystallization temperature was decreased with decreasing PbO content x. A maximum conductivity of 6.2 × 10-7 S·cm-1 at 373 K was obtained for x=0.32 glass plate prepared by the iron pressing method. This value is almost equal to the maximum conductivity of anion conducting glasses reported. I- ions would be the sole carrier ions, based on an estimation of the electromotive force of the I2 concentration cell.
  • H Aono, E Sugimoto
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 79 (10) 2786 - 2788 0002-7820 1996/10 [Peer-reviewed]
     Scientific journal 
    Sodium-rich NASICON-type ceramics, the NaM(2)(PO4)(3) + yNa(2)O (M = Ge, Ti, Hf, Zr) systems, were investigated in order to obtain a material having a high Na+ conductivity and high density, The ionic conductivity and the sinterability were greatly improved by an increase in the value off for all of the systems examined. Added Na2O was not soluble in the NASICON-type skeleton, since the lattice constants and the X-ray diffraction patterns were not changed by the Na2O addition in all of the samples, Na2O acts as a flux for obtaining highly dense ceramics and highly conductive grain boundaries. Partial A(2) site insertion by Na+ ions is effective for the enhancement of conductivity, because the conductivity for Na(1.5)M(III)(0.5)Zr-1.5(PO4)(3) (M = In or Y) is about 1 order of magnitude higher than the maximum conductivity of the NaZr2(PO4)(3) + yNa(2)O system.
  • H Aono, E Sugimoto
    JOURNAL OF THE AMERICAN CERAMIC SOCIETY 79 (10) 2786 - 2788 0002-7820 1996/10 Scientific journal 
    Sodium-rich NASICON-type ceramics, the NaM(2)(PO4)(3) + yNa(2)O (M = Ge, Ti, Hf, Zr) systems, were investigated in order to obtain a material having a high Na+ conductivity and high density, The ionic conductivity and the sinterability were greatly improved by an increase in the value off for all of the systems examined. Added Na2O was not soluble in the NASICON-type skeleton, since the lattice constants and the X-ray diffraction patterns were not changed by the Na2O addition in all of the samples, Na2O acts as a flux for obtaining highly dense ceramics and highly conductive grain boundaries. Partial A(2) site insertion by Na+ ions is effective for the enhancement of conductivity, because the conductivity for Na(1.5)M(III)(0.5)Zr-1.5(PO4)(3) (M = In or Y) is about 1 order of magnitude higher than the maximum conductivity of the NaZr2(PO4)(3) + yNa(2)O system.
  • H Aono, E Sugimoto
    JOURNAL OF THE CERAMIC SOCIETY OF JAPAN 104 (3) 235 - 238 1882-0743 1996/03 Scientific journal 
    A glassy solid electrolyte of the (1-x)PbI2-xPbO system was prepared using two kinds of quenching methods. In the case of the iron pressing method, 0.68PbI(2)-0.32PbO (x=0.32) glass was obtained when PbI2 melt reacts with oxygen in air. In the case of the quenching method using ice water, the glassy sample was not obtained when x<0.35. Conductivity was enhanced and crystallization temperature was decreased with decreasing PbO content x. A maximum conductivity of 6.2 x 10(-7) S . cm(-1) at 373 K was obtained for x=0.32 glass plate prepared by the iron pressing method. This value is almost equal to the maximum conductivity of anion conducting glasses reported, I- ions would be the sole carrier ions, based on an estimation of the electromotive force of the I-2 concentration cell.
  • AONO Hiromichi, SUGIMOTO Eisuke
    Journal of the Ceramic Society of Japan 社団法人日本セラミックス協会 104 (1207) 235 - 238 0914-5400 1996/03 
    A glassy solid electrolyte of the(1-x)PbI_2-xPbO system was prepared using two kinds of quenching methods. In the case of the iron pressing method, 0.68PbI_2-0.32PbO(x=0.32)glass was obtained when PbI_2 melt reacts with oxygen in air. In the case of the quenching method using ice water, the glassy sample was not obtained when x<0.35. Conductivity was enhanced and crystallization temperature was decreased with decreasing PbO content x. A maximum conductivity of 6.2×10^<-7> S・cm^<-1> at 373 K was obtained for x=0.32 glass plate prepared by the iron pressing method. This value is almost equal to the maximum conductivity of anion conducting glasses reported. I^- ions would be the sole carrier ions, based on an estimation of the electromotive force of the I_2 concentration cell.
  • GY Adachi, N Imanaka, H Aono
    ADVANCED MATERIALS 8 (2) 127 - + 0935-9648 1996/02 [Peer-reviewed][Invited]
     Scientific journal 
    The all-solid, lithium rechargeable battery, which if available would find many applications, is one reason for carrying out research into Li+-conducting solids. Fast Li+-conducting ceramic electrolytes are reviewed with regard to their electrical properties and crystal structure. Both non-oxide based ceramics and oxide materials are considered, and possibilities for further developments-e.g., the preparation of the electrolyte by thin him techniques-are pointed out.
  • GY Adachi, N Imanaka, H Aono
    ADVANCED MATERIALS 8 (2) 127 - + 0935-9648 1996/02 
    The all-solid, lithium rechargeable battery, which if available would find many applications, is one reason for carrying out research into Li+-conducting solids. Fast Li+-conducting ceramic electrolytes are reviewed with regard to their electrical properties and crystal structure. Both non-oxide based ceramics and oxide materials are considered, and possibilities for further developments-e.g., the preparation of the electrolyte by thin him techniques-are pointed out.
  • H Aono, A Yamabayashi, E Sugimoto, Y Mori, Y Sadaoka
    CHEMISTRY LETTERS (8) 689 - 690 0366-7022 1996 Scientific journal 
    A Cl-2 gas sensor with a 0.97PbCl(2)-0.03KCl solid electrolyte and a Pb reference electrode was prepared by a melting method using an evacuated closed tube. The electromotive force (EMF) measured at 573 K agreed with the calculated value for Cl-2 gas concentrations from 10 ppm to 1000 ppm. The response time was long when the operating temperature is lower than 473 K.
  • H Aono, A Yamabayashi, E Sugimoto, Y Mori, Y Sadaoka
    CHEMISTRY LETTERS (8) 689 - 690 0366-7022 1996 Scientific journal 
    A Cl-2 gas sensor with a 0.97PbCl(2)-0.03KCl solid electrolyte and a Pb reference electrode was prepared by a melting method using an evacuated closed tube. The electromotive force (EMF) measured at 573 K agreed with the calculated value for Cl-2 gas concentrations from 10 ppm to 1000 ppm. The response time was long when the operating temperature is lower than 473 K.
  • Susumu Nakayama, Tatsuya Kageyama, Hiromichi Aono, Yoshihiko Sadaoka
    Journal of Materials Chemistry 5 1801 - 1805 0959-9428 1995/12 Scientific journal 
    Ionic conductivities have been investigated for lanthanoid silicates of the Ln10(SiO4)6O3 solid solution series and related compounds. The activation energy and conductivity at 500°C were estimated to be 69 kJ mol-1 and 1.8 x10-4 S cm -1 for La10(SiO4)6O3 and 71 kJ mol-1 and 1.5x10-4S cm 1 for Nd 10(SiO4)6O3. The a and c lattice constants of the hexagonal phase decreased with decreasing radius of the Ln 3+ ion for Ln10(SiO4)6O3 (Ln=La, Nd, Sm, Gd and Dy). The activation energy increased and the conductivity decreased when Ln3+ ions with smaller ionic radii were used. The sole carrier in these materials is the O2- ion.
  • S NAKAYAMA, T KAGEYAMA, H AONO, Y SADAOKA
    JOURNAL OF MATERIALS CHEMISTRY 5 (11) 1801 - 1805 0959-9428 1995/11 Scientific journal 
    Ionic conductivities have been investigated for lanthanoid silicates of the Ln(10)(SiO4)(6)O-3 solid solution series and related compounds. The activation energy and conductivity at 500 degrees C were estimated to be 69 kJ mol(-1) and 1.8 x 10(-4) S cm(-1) for La-10(SiO4)(6)O-3 and 71 kJ mol(-1) and 1.5 x 10(-4) S cm(-1) for Nd-10(SiO4)(6)O-3. The a and c lattice constants of the hexagonal phase decreased with decreasing radius of the Ln(3+) ion for Ln(10)(SiO4)(6)O-3 (Ln = La, Nd, Sm, Gd and Dy). The activation energy increased and the conductivity decreased when Ln(3+) ions with smaller ionic radii were used. The sole carrier in these materials is the O2- ion.
  • S NAKAYAMA, H AONO, Y SADAOKA
    CHEMISTRY LETTERS (6) 431 - 432 0366-7022 1995/06 Scientific journal 
    Electrical properties were investigated for lanthanoid- silicates of Ln(10)(SiO4)(6)O-3 (Ln=La, Nd, Sm, Gd and Nd). The conductivity at 773 K was 2.3 X 10(4) S cm(-1) for Nd-10(SiO4)(6)O-3. The sole carrier is the O2- ion, which was determined using an O-2 gas concentration cell.
  • H AONO, E SUGIMOTO
    CHEMISTRY OF MATERIALS 7 (6) 1233 - 1236 0897-4756 1995/06 Scientific journal 
    The electrical conductivity of (1 - x)PbBr2 . xKBr solid electrolytes is enhanced on increasing x to x = 0.02. The maximum conductivity, 2.7 x 10(-6) S . cm(-1) at 298 K was obtained for x = 0.02. The transference number for the Br- ion is almost equal to 1, which was determined by the Tubandt's method, dc conductivity with Au electrodes, and the electromotive force of a Br-2 gas concentration cell. The Ba-based system, (1 - x)BaBr2 . xKBr solid electrolyte, has a lower conductivity compared with that for the Pb-based system.
  • Hiromichi Aono, Eisuke Sugimoto
    Chemistry of Materials 7 (6) 1233 - 1236 1520-5002 1995 [Peer-reviewed]
     Scientific journal 
    The electrical conductivity of (1 - x)PbBr2•xKBr solid electrolytes is enhanced on increasing x to x = 0.02. The maximum conductivity, 2.7 x 10-6 S•cm-1 at 298 K was obtained for x = 0.02. The transference number for the Br- ion is almost equal to 1, which was determined by the Tubandt's method, dc conductivity with Au electrodes, and the electromotive force of a Br2 gas concentration cell. The Ba-based system, (1 - x)BaBr2•xKBr solid electrolyte, has a lower conductivity compared with that for the Pb-based system. © 1995, American Chemical Society. All rights reserved.
  • H AONO, E SUGIMOTO
    CHEMISTRY LETTERS (1) 79 - 79 0366-7022 1995/01 Scientific journal 
    The electrical conductivity of (1-x)PbBr2 . xKBr solid electrolytes enhanced with increasing x up to x=0.02, where 2.7X10(-6) S . cm(-1) at 298 K was obtained. The carrier ion for this system was Bi, as determined by the Tubandt's method.
  • H AONO, N IMANAKA, G ADACHI
    ACCOUNTS OF CHEMICAL RESEARCH 27 (9) 265 - 270 0001-4842 1994/09 [Peer-reviewed]
     Scientific journal
  • H AONO, N IMANAKA, G ADACHI
    ACCOUNTS OF CHEMICAL RESEARCH 27 (9) 265 - 270 0001-4842 1994/09
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, GY ADACHI
    CHEMISTRY LETTERS (12) 2033 - 2036 0366-7022 1993/12 Scientific journal 
    The electrical properties were studied for the (1-y)Li3Cr2(PO4)3-yLi5Mg2(PO4)3 system. The Mg2+ ion can not replace the Cr3+ site. The crystal structure for Li3Cr2(PO4)3 in this system is the beta-Fe2(SO4)3 type monoclinic phase. The conductivity and the sinterability improve with the increase in y for the phosphate system. The maximum conductivity was 4.6x10(-5) S.cm-1 at 298 K for y=0.2. The activation energy for a Li+ ion migration at the bulk component was ca. 0.43 eV for all the samples.
  • H AONO, E SUGIMOTO, Y MORI, Y OKAJIMA
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 140 (11) 3199 - 3203 0013-4651 1993/11 Scientific journal 
    A Cl2 gas sensor using BaCl2-KCl solid electrolyte was investigated. The conductivity was greatly enhanced by KCl doping of the (1 - x) BaCl2-xKCl system, and a maximum conductivity of 5.6 x 10(-5) S . cm-1 at 573 K was obtained for x = 0.02. The sensor probe was prepared by a melting method at 1373 K. The electromotive force (EMF) measurement with the Cl2 gas sensor using the 0.97BaCl2-0.03KCl solid electrolyte was performed with an Ag-AgCl solid reference electrode and an RUO2 measuring electrode. Good agreement between the measured and the calculated EMF values was obtained for Cl2 gas concentrations from 50 to 10,000 ppm at 623 K. The EMF response time with a change in Cl2 concentration is ca. 1 min for above 100 ppm and 2 to 5 min for lower concentrations. The measured EMF was not influenced by O2 or CO2 gas concentration. This sensor probe was very stable in the presence of water vapor at 623 K during a 90 day test period.
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, GY ADACHI
    SOLID STATE IONICS 62 (3-4) 309 - 316 0167-2738 1993/08 Scientific journal 
    The electrical properties and the crystal structure were investigated for the ceramic electrolytes based on LiHf2(PO4)3. The conductivity enhanced by the Li2O addition with LiHf2(PO4)3 system and by the increase of x for Li1+xMxHf2-x(PO4)3 (M = Cr, Fe, Sc, In, Lu or Y) systems. The P2(1)/n monoclinic phase transformed to NASICON-type R3cBAR rhombohedral phase at above 1173 K. The activation energy for Li+ ion migration was decreased by the phase transition. The activation energy for bulk component was 0.42 eV for the NASICON-type structure. A maximum conductivity at 298 K is 1.7 x 10(-4) S.cm-1 for the sample of Li1.2Fe0.2Hf1.8(PO4)3.
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, G ADACHI
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 140 (7) 1827 - 1833 0013-4651 1993/07 Scientific journal 
    The electrical properties of systems of LiMxTi2-x(PO4)3+yLi2O, M = Ge, Sn, Hf, and Zr, were examined in detail. The conductivity and the sinterability increased with the amount of excess lithium oxide in the phosphate. The secondary Li2O phase acts as a flux to accelerate the sintering process and to obtain high conductivity grain boundaries. The conductivity decreased and the activation energy of the bulk component for Li+ migration increased by the partial substitution of Ti4+ for M4+ in systems of LiMxTi2-x(PO4)3+0.2Li2O, M = Ge, Sn, Hf, and Zr. A minimum activation energy of 0.28-0.30 eV, was obtained for the sample with ca. 1310 angstrom3 in the cell volume. LiTi2(PO4)3 has the most suitable tunnel size for a Li+ migration through the NASICON-type network structure.
  • H AONO, E SUGIMOTO, Y MORI, Y OKAJIMA
    CHEMISTRY LETTERS (6) 1039 - 1042 0366-7022 1993/06 Scientific journal 
    The Cl2 gas sensor using 0.97BaCl2-0.03KCl solid electrolyte and an Ag metal reference electrode was prepared by a melting method. The melting method has the advantage of ease for the sensor preparation. The sensor probe obtained has a high mechanical strength. The measured EMF agreed with the calculated one for Cl2 gas concentrations from 50 ppm to 10000 ppm.
  • リン酸塩リチウムイオン伝導体
    足立吟也, 青野宏通
    Phosphorus Letter (9) 8 - 12 1992/09 [Invited]
     Research society
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, GY ADACHI
    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 65 (8) 2200 - 2204 0009-2673 1992/08 Scientific journal 
    The electrical properties and sinterability were studied for Li1+xMxGe2-x(PO4)3, M=Al3+, Cr3+, Ga3+, Fe3+, Sc3+, and In3+ systems. Due to the closer ionic radius of Al3+ and Cr3+ Compared to that of Ge4+, those M3+ ions easily substitute the Ge4+ site. Larger cations, such as Ga3+, Fe3+, SC3+, and In3+, were difficult to substitute the Ge4+ site. The ionic conductivity and sinterability improved with an increase in x for all of the M3+-substituted systems. In particular, an Al3+- or Cr3+-substituted system shows higher conductivity; the maximum conductivity is 2.4X10(-4) S cm-1 at 298 K for Li1.5Al0.5Ge1.5(PO4)3. The enhancement in the conductivity is attributed to a decrease in the porosity and a lowering of the activation energy in the grain boundaries. The activation energy for Li+ ion conduction of the bulk component was 0.38 eV for Li1+xMxGe2-x(PO4)3 electrolytes, and was almost independent of M3+ substitution.
  • 足立 吟也, 青野 宏通
    セラミックス 日本セラミックス協会 27 (2) 117 - 21 0009-031X 1992/02
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, G ADACHI
    CHEMISTRY LETTERS (9) 1567 - 1570 0366-7022 1991/09 Scientific journal 
    The ionic conductivity of a solid electrolyte, Li1.3Al0.3Ti1.7 (PO4)3, was measured with Li and Li-Al alloy electrodes. The contact resistance between the Li electrode and the electrolyte was a dominant factor for the DC conductivity. A higher DC conductivity was obtained by an utilization of the Li4Al alloy electrodes.
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, G ADACHI
    SOLID STATE IONICS 47 (3-4) 257 - 264 0167-2738 1991/09 Scientific journal 
    A lithium salt (Li3PO4 or Li3BO3) was added to LiTi2(PO4)3 to obtain a dense pellet of the phosphate. The porosity of the sintered pellets decreased and the conductivity was enhanced by the utilization of a binder. A maximum conductivity of 3.0 x 10(-4) S.cm-1 at 298 K was obtained for a sample of LiTi2(PO4)3-0.2Li3BO3. The activation energy for the lithium migration at grain boundaries was decreased by the addition of lithium salt. The reason for the conductivity enhancement was attributed to a decrease in the activation energy for the lithium migration at the grain boundary and an increase in the contact area between grains. The conductivity of the bulk component was also increased by the enhancement of Li+-ion migration at grain boundaries.
  • Hiromichi Aono, Eisuke Sugimoto, Yoshihiko Sadaoka, Nobuhito Imanaka, Gin-ya Adachi
    Solid State Ionics 47 (3-4) 257 - 264 0167-2738 1991 [Peer-reviewed]
     Scientific journal 
    A lithium salt (Li3PO4 or Li3BO3) was added to LiTi2(PO4)3 to obtain a dense pellet of the phosphate. The porosity of the sintered pellets decreased and the conductivity was enhanced by the utilization of a binder. A maximum conductivity of 3.0 × 10-4 S·cm-1 at 298 K was obtained for a sample of LiTi2(PO4)3-0.2Li3BO3. The activation energy for the lithium migration at grain boundaries was decreased by the addition of lithium salt. The reason for the conductivity enhancement was attributed to a decrease in the activation energy for the lithium migration at the grain boundary and an increase in the contact area between grains. The conductivity of the bulk component was also increased by the enhancement of Li+-ion migration at grain boundaries. © 1991.
  • SUGIMOTO Eisuke, AONO Hiromichi, FUKUSHIMA Koichi, KIMURA Takayoshi, IIJIMA Shigeru, KOZUKA Zensaku
    Journal of MMIJ The Mining and Materials Processing Institute of Japan 107 (12) 899 - 903 0916-1740 1991 
    The present study was undertaken to investigate the practical use of SO<SUB>2</SUB> gas sensor employing β″-alumina solid electrolyte in the field of industry. In the cell with β″-alumina solid electrolyte, the use of (β″+β″)-alumina coexistent mixture in air as a solid reference electrode lead to a simple structure of the SO<SUB>2</SUB> gas sensor. In this paper we reported the practical application of SO<SUB>2</SUB> gas sensor with the following cell in copper smelting plants.<BR>Pt, (β+β″)-alumina in air/β″-alumina/S0<SUB>2</SUB>+O<SUB>2</SUB>+SO<SUB>3</SUB>, Pt<BR>From the present experiments the following conclusions were obtained.<BR>1) The present experimental cell showed a satisfactory response and the data agreed very closely with those obtained by another analytical method (non-dispersive infrared rays).<BR>2) In a long period of measuring, the emf's of this sensor varied with the lapse of time. However it was confirmed that its reproducibility is obtained by the correction of the calibration curve once a few days.
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, G ADACHI
    CHEMISTRY LETTERS (10) 1825 - 1828 0366-7022 1990/10 Scientific journal
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, G ADACHI
    JOURNAL OF THE ELECTROCHEMICAL SOCIETY 137 (4) 1023 - 1027 0013-4651 1990/04 Scientific journal
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, GY ADACHI
    CHEMISTRY LETTERS (3) 331 - 334 0366-7022 1990/03 Scientific journal
  • Hiromichi Aono, Eisuke Sugimoto, Yoshihiko Sadaoka, Nobuhito Imanaka, Gin-ya Adachi
    Solid State Ionics 40-41 (1) 38 - 42 0167-2738 1990 [Peer-reviewed]
     Scientific journal 
    Lithium titanium phosphates mixed with various metal ions of M3+ (M=Al, Cr, Ga, Fe, Sc, In, Lu, Y, or La), Li1+xMxTi2-x(PO4)3 systems, were prepared, and their properties were investigated. The conductiv ity was enhanced and the porosity of the sintered pellets decreased by the partial replacement of Ti4+ with the M3+ ion. The porosity was considerably influenced by the ionic radius of the M3+ ion. The sinterability was greatly related to the increase of lithium concentrations at the grain boundary. The conductivity enhancement by the substitution mainly resulted from the densification of the sintered pellets. © 1990.
  • 足立 吟也, 青野 宏通
    化学 化学同人 44 (11) p766 - 767 0451-1964 1989/11
  • Hiromichi Aono, Eisuke Sugimoto
    Journal of the Electrochemical Society 136 (2) 590 - 591 1945-7111 1989 [Peer-reviewed]
     Scientific journal
  • 青野 宏通
    新居浜工業高等専門学校紀要 理工学編 新居浜工業高等専門学校 (24) p112 - 116 0286-2743 1988/01
  • Y SADAOKA, M MATSUGUCHI, Y SAKAI, H AONO, S NAKAYAMA, H KUROSHIMA
    JOURNAL OF MATERIALS SCIENCE 22 (10) 3685 - 3692 0022-2461 1987/10 Scientific journal
  • Y SADAOKA, H AONO, Y SAKAI, S NAKAYAMA, H KUROSIMA
    JOURNAL OF MATERIALS SCIENCE LETTERS 5 (9) 923 - 924 0261-8028 1986/09 Scientific journal

Books etc

  • 学部共通実験
    愛媛大学工学部学部共通実験担当グループ 青野他 全12名 (Joint work, 第1部 緒論 pp.1-11)
    学術図書出版社 2019/07
  • NANOSTRUCTURES FOR NOVELTHERAPY
    Hiromichi TAKEBE, Sengo KOBAYASHI, Hiromichi AONO, Saeki YAMAMURO (Joint work, Chapter 4 [FABRICATION AND CHARACTERIZATION OF NATURAL/SYNTHESIZED, MICRO-, AND NANOSTRUCTURED MATERIALS FOR BIOMEDICAL APPLICATIONS])
    Elsevier 2017/03
  • レアメタル便覧
    足立吟也監修 (分担執筆(16章固体イオニクス用イオン伝導性材料および化学センサー 担当))
    丸善 2011
  • 現代無機材料化学
    (分担執筆(11章6節 化学センサ担当))
    化学同人 2006
  • 化学教科書シリーズ「固体化学の基礎と無機材料」(共著)
    (分担執筆(pp.141-160担当))
    丸善出版丸善出版(共著) 1995
  • Basic of Solid State Chemistry and Inorganic Materials
    1995

Conference Activities & Talks

Works

  • 除染等に用いる新規ゼオライトおよび複合材料の研究
    2011 - Today
  • 燃料電池の電極材料および触媒材料の研究
    2007 - Today
  • 交流磁場焼灼療法に用いる磁性材料の研究
    2001 - Today
  • 多核錯体などの前駆体の合成と低温熱分解による複合酸化物微粒子の作製
    1996 - Today
  • ガスセンサに用いる材料の開発
    1990 - Today
  • 新規固体電解質の開発
    青野 宏通 1987 -1998

MISC

  • 田中守生, 平澤英之, SANGAA D, TSOGBADRAKH N, 青野宏通  日本材料学会四国支部学術講演会講演論文集  16th-  19‐20  2018
  • ゾルゲル法前駆体の分子設計による微粒子の高機能化と低温合成
    責任著者, 脇谷 尚樹, 共著者]ダスハリナラヤン, 川口昂彦, 坂元尚紀, 鈴木久男, 青野宏通, 篠崎和夫  工業材料  64-  (12)  36  -41  2016/12
  • 高橋龍一郎, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  29th-  ROMBUNNO.1Q02  2016/08
  • 松枝 直人, Wazingwa Munthali Moses, 青野 宏通, Johan Erni  日本土壌肥料学会講演要旨集  62-  (0)  290  -290  2016
  • 神田康孝, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  28th-  ROMBUNNO.1M03  2015/09
  • 國本太歩, 鍛治紀彰, JOHAN Erni, 尾上清利, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  28th-  ROMBUNNO.1M22  2015/09
  • 鍛治紀彰, 國本太歩, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会年会講演予稿集(CD-ROM)  2015-  ROMBUNNO.3G02  2015/03
  • 山内陽平, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会年会講演予稿集(CD-ROM)  2015-  ROMBUNNO.2B34  2015/03
  • 吉田昂平, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会年会講演予稿集(CD-ROM)  2015-  ROMBUNNO.3G01  2015/03
  • 金山恵亮, JOHAN Erni, 松枝直人, 板垣吉晃, 青野宏通  日本セラミックス協会年会講演予稿集(CD-ROM)  2015-  ROMBUNNO.2B33  2015/03
  • 青野宏通, 國本太歩, 鍛治紀彰, JOHAN Erni, 板垣吉晃, 尾上清利, 松枝直人  資源・素材(Web)  2015-  ROMBUNNO.3714 (WEB ONLY)  2015
  • 山内陽平, 板垣吉晃, JOHAN Erni, 松枝直人, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  27th-  ROMBUNNO.1M24  2014/08
  • 鍛治紀彰, 國本太歩, 板垣吉晃, JOHAN Erni, 松枝直人, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  27th-  ROMBUNNO.1M25  2014/08
  • 松枝直人, ERNI Johan, MUNTHALI Moses, 山田登志夫, 青野宏通, 山本徹  日本土壌肥料学会講演要旨集  59-  31  2013/09
  • 山野裕飛, 西森忠彦, 板垣吉晃, 猶原隆, 青野宏通, 平澤英之  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  26th-  ROMBUNNO.2F08  2013/08
  • 山田啓三, 板垣吉晃, JOHAN Erni, 山本徹, 松枝直人, 逸見彰男, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  26th-  ROMBUNNO.1F20  2013/08
  • 溝口裕己, 板垣吉晃, 山本徹, 松枝直人, 逸見彰男, 青野宏通  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  26th-  ROMBUNNO.1F19  2013/08
  • 青野宏通, 山本徹, 松枝直人, 逸見彰男  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  26th-  ROMBUNNO.2F17  2013/08
  • 田村一将, 青野宏通, 山本徹, 松枝直人, 逸見彰男  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  26th-  ROMBUNNO.2PF01  2013/08
  • 高橋宏至, 松友真哉, 平澤英之, 猶原隆, 青野宏通  電気関係学会四国支部連合大会講演論文集(CD-ROM)  2012-  ROMBUNNO.14-25  2012/09
  • 秋山祐輔, 西森忠彦, 青野宏通, 猶原隆, 前原常弘, 平澤英之  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  25th-  ROMBUNNO.3H15  2012/09
  • 青野宏通, 渡部祐輔, 田村一将, 山本徹, 松枝直人, 逸見彰男  日本セラミックス協会秋季シンポジウム講演予稿集(CD-ROM)  25th-  ROMBUNNO.3H14  2012/09
  • 樋口貴文, 猶原隆, 青野宏通, 前原常弘, 渡部祐司, 平澤英之, 松友真哉  日本金属学会講演概要(CD-ROM)  150th-  ROMBUNNO.169  2012/03
  • Nishimori Tadahiko, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2012-  (0)  544  -544  2012  
    We synthesized the Y<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB> powder using a reverse coprecipitation method. The maximum heat generation ability was obtained for the sample calcined at 1100<SUP>o</SUP>C. Heat generation ability of the Y<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB> is proportional to the cube of the strength of magnetic field. The hysteresis loss value for the B-H curve agreed with the heat generation ability for the sample calcined at lower than 1100<SUP>o</SUP>C.
  • Tamura Kazumasa, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2012-  (0)  158  -158  2012  
    We prepared the rare earth iron garnet R<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB> using a reverse coprecipitation method, and then nano-sized powder was prepared by bead milling. The maximum heat generation ability was obtained for Y<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>. Magnetic moment of the sample did not influence the heat generation ability at all.
  • Akiyama Yusuke, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2012-  (0)  159  -159  2012  
    Nano-sized Y<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB> ferrite powder prepared by bead milling was calcined to clarify the effect of particle growth on the heat generation mechanism in AC magnetic field. The maximum heat generation ability of 0.46W•g<SUP>-1</SUP> (1.77kA•m<SUP>-1</SUP>,370kHz) was obtained for the sample calcined at 700oC. Although the suparparamagnetic material was obtained for the sample calcined at low temperature, the ferrimagnetic property showed for that calcined at 700<SUP>o</SUP>C (particle size 37nm).
  • 猶原隆, 青野宏通, 前原常弘, 渡部祐司, 平澤英之, 松友真哉  日本金属学会講演概要(CD-ROM)  149th-  ROMBUNNO.305  2011/10
  • 洗川隼人, 小林千悟, 仲井清眞, 武部博倫, 青野宏通, 岡野聡, 阪本辰顕  日本金属学会講演概要  148th-  201  2011/04
  • Watanabe Yusuke, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  67  -67  2011  
    新しい癌の治療法として磁性材料を発熱させ焼灼させる交流磁場焼灼療法が期待されている。その材料としては特にマグネタイトが研究されてきた。本研究ではこのマグネタイトの合成法として、化学的な逆共沈法と物理的なビーズミル粉砕双方を用いて超常磁性体であるナノ微粒子を作製し、磁場強度と周波数との関係を調べ, 発熱機構について検討した。 その結果、発熱能はほぼ同程度で、どちらの方法とも発熱能は磁場強度の2乗と周波数に比例することがわかった。また、500℃程度の低温焼成がきわめて効果的であり、発熱能が倍以上に増大した。
  • Nishimori Tadahiko, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  65  -65  2011  
    癌の新しい治療法として交流磁場焼灼療法が注目されており, 交流磁場中での優れた発熱特性を持つ磁性材料が期待されている。今回, 逆共沈法により前駆体を作製し1000~1200℃で焼成しY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>フェライト粉末を得た。 その結果1100℃で焼成した粉末材料が最も発熱能が大きく、粒子成長が強く関わっていることがわかった。交流磁場中での発熱特性について磁場強度や周波数との関連性について検討を行ったところ、発熱能(W•g<SUP>-1</SUP>)は周波数(kHz)および磁場の3乗(kA•m<SUP>-1</SUP>)に比例することがわかった。この発熱能は試料の形状にも強く影響され、磁場と並行に試料を置いた場合、磁場を収束し発熱が著しく大きくなった。
  • Senba Ryouta, Ebara Hiroki, Aono Hiromichi, Naohara takashi, Maehara tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  64  -64  2011  
    癌の新しい治療法への応用を目的として交流磁場中において優れた発熱能をもつ磁性材料が期待されている。本研究では、ビーズミルを用いて物理的粉砕したY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>超常磁性体についてその発熱能について検討し、さらに血管の塞栓法への応用を目的として、スプレードライを用いて20~32μmのフェライトマイクロ球体を作製した。 発熱能については、磁場の2乗に比例しマグネタイトよりも優れた材料であることがわかった。さらに、スプレードライ法および液中の分散法をもちいることにより6.6_%_の収率で20~32μmのフェライトマイクロ球体を得ることが出来た。
  • Nishimori Tadahiko, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  319  -319  2011  
    癌の新しい治療法として交流磁場焼灼療法が注目されており, 交流磁場中での優れた発熱特性を持つ磁性材料が期待されている。我々はこれまでにフェリ磁性体であるY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>系フェライトが優れた発熱特性を持つことを報告した。今回, 逆共沈法によりY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>フェライトを作製し交流磁場中での発熱特性について磁場強度や周波数との関連性について検討を行った。 最大の発熱量を示した1100℃焼成の試料について磁場強度と発熱量の関係を調べたところ, 発熱量は磁場強度の3乗に比例することがわかった。これはB-Hアナライザにより磁性体粉末の保磁力が磁場強度(H/kA・m<SUP>-1</SUP>)の2乗に依存するため, ヒステリシス損失がHの3乗に比例して増大することがわかった。一方, 発熱量は周波数(f/kHz)に比例していた。このことはナノ微粒子化した超常磁性体の発熱がHの2乗に比例することとは異なる挙動である。これらのことを用いて発熱量P(W・g<SUP>-1</SUP>)は比例定数kを用いてP=k・f・H<SUP>3</SUP>で表され, 実験結果よりk=2.7×10<SUP>-1</SUP>となった。これにより発熱量はfとHがわかれば計算により求めることができる。
  • Watanabe Yusuke, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  318  -318  2011  
    新しい癌の治療法として磁性材料を発熱させ焼灼させる交流磁場焼灼療法が期待されている。我々はこれまでに, 市販のFeFe<SUB>2</SUB>O<SUB>4</SUB>をビーズミル物理的粉砕することにより交流磁場中での発熱能が著しく向上することを報告している。そこで本研究では, ビーズミル粉砕したFeFe<SUB>2</SUB>O<SUB>4</SUB>の最も発熱する試料について磁場強度と周波数との関係を調べ, 発熱機構について検討した。 結果として, ビーズミル粉砕で試料は超常磁性粒子となり, 磁気モーメントの遅れであるネール緩和が支配的であると考えられる。一方, 発熱量は周波数に対して比例することがわかった。これらより発熱量PがP=k·f·H<SUP>2</SUP>(f=周波数[kHz], H=磁場強度[kA·m<SUP>-1</SUP>], k=比例定数)と表わすことが可能であり, (a)の発熱量P=1.07×10<SUP>-4</SUP>·f·H<SUP>2</SUP>の関係式が得られた。また, 低温焼成試料については約2.5倍発熱能(k値)が増大した。
  • Ebara Hiroki, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  25  -25  2011  
    我々は、ビーズミルを用いた物理的粉砕により微粒子化したイットリウムガーネットY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>がきわめて優れた発熱特性を示すことを報告している。一般的に強磁性体の発熱原因としてB-H曲線におけるヒステリシス損失と渦電流損失が考えられる。またビーズミル粉砕により超常磁性体となった場合、Néel緩和による発熱とBrownian緩和による発熱が考えられる。本研究ではY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>についてビーズミル粉砕により作製した微粒子材料の発熱能の増大とその発熱機構について検討した。 B-Hアナライザによるヒステリシス損失と発熱特性の間に強い相関関係があり、ヒステリシス損失の外挿値、粉末及び固化試料の実測値がほぼ同じ直線上にのることがわかった。今回測定を行った1.77 kA/mでの発熱量は約0.4 W•g<SUP>-1</SUP>であり、発熱量は交流磁場の周波数f(kHz)と比例関係にあることを確認しており: P = 3.5×10<SUP>-4</SUP>fH<SUP>2</SUP>の関係があることが明らかになった。従って、この関係を用いて、磁場強度と周波数を変化させた場合の発熱能を見積もることが可能となった。
  • Senba Ryouta, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2011-  (0)  450  -450  2011  
    癌の新しい治療法への応用を目的として交流磁場中において優れた発熱能をもつ磁性材料が期待されている。我々はこれまでにビーズミルを用いて物理的粉砕したY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>が優れた発熱特性を示すことを報告している。塞栓法では, 血管を傷付けずに塞栓させるために, 磁性材料を球状かつ粒子の大きさを20~30μmにする必要がある。本研究では, 交流磁場中で優れた発熱能をもつY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>を用い, スプレードライ法によってY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>フェライトマイクロ球体を作製し発熱特性の検討を行った。 Y<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>フェライトマイクロ球体の作製は, 純水(11.25ml)と微粒子化したY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>粉末(4g)を混合し, スプレードライ法によって行った。スプレードライ法によって回収した粉末を32μmと20μmのふるいを用い, 20~32μmに分級した。 分級前は多くの粒子が混在しているが, 分級後はそろったマイクロ球体が見られた。この収率はスプレードライに入れた粉末材料4gに対して約6.6%であった。さらにスプレードライ後の発熱特性についても検討を行った。
  • AONO H, HIRAZAWA H, NAOHARA T, MAEHARA T, WATANABE Y  希土類 = Rare earths  (56)  108  -109  2010/05
  • 森谷健史, 青野宏通, 猶原隆, 前原常弘, 渡部祐司, 平澤英之  日本セラミックス協会年会講演予稿集  2010-  285  2010/03
  • Ebara Hiroki, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2010-  (0)  2P093  -2P093  2010  
    新しい癌の治療法として磁性材料の交流磁場中での発熱を利用する交流磁場焼灼療法が期待されている。我々は、発熱特性の優れた新規材料について検討を行なってきており、最近ではイットリウムガーネットY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>がきわめて優れた発熱特性を示すことを報告している。一方、様々なフェライトについてビーズミルによる微粒子化が有効であることについても明らかにしてきている。 本研究ではY<SUB>3</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>についてビーズミルを用いて物理的粉砕し様々な粒子径、結晶子径のものを作製し検討した。市販の粉末は数μm程度の粒子径であり、交流磁場中では全く発熱しなかった。0.3mmφのビーズミル粉砕により発熱特性は上昇し、これは単磁区粒子生成によると考えられる。粉砕時間の増加に伴い、また使用するビーズ径が小さくなるにつれ微粒子化が進んだ。粉砕を行うことで発熱特性はさらに向上し、0.1mmφで4時間粉砕したもので結晶子径約16nmとなり、最大のΔT=60℃が得られた。さらに微粒子化が進むと超常磁性粒子が多く生成するため発熱特性は低下した。
  • 青野宏通, 猶原隆, 前原常弘, 渡部祐司, 平澤英之  日本化学会西日本大会講演要旨集  2009-  35  2009/11
  • Hirazawa Hideyuki, Sasaki Hiroomi, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Sato Mitsunori  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2009-  (0)  234  -234  2009  
    The sized nano MgFe2O4 ferrite powder having heat generation ability in an AC magnetic field was prepared by bead milling and studied for application in thermal coagulation therapy. The heat ability was improved by a decrease in crystal size using bead mill. The maximum ability obtained for the sample having 6.2 nm in crystal size. After the milling, the calcination of the sample was also effective for the improvement of the heat ability.
  • Hirazawa Hideyuki, Sasaki Hiroomi, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Sato Mitsunori  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2009-  (0)  2B24  -2B24  2009  
    マグネタイトは、交流磁場中で発熱する材料として注目されている。その発熱メカニズムは現在厳密には解明されていないが、粒子・結晶子サイズに起因するヒステリシス損失の増大により強く発熱すると報告されている。これまでに、化学的製法で異なる粒子径・結晶子径を持つマグネタイトを作製したところ、粒子径約13nm、結晶子径約12nmで最大の発熱を示したが、十分な粒子範囲について検討できていない。そこで本研究では、ビーズミルによりマグネタイトを粉砕、及び窒素雰囲気中で焼成することにより得られた異なる粒子サイズを示す粉末試料について、交流磁場中での発熱実験を行った。
  • Yoneda Keiichi, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2009-  (0)  2B26  -2B26  2009  
    癌の新しい焼灼療法への応用を目的として交流磁場中において発熱能の優れた磁性材料が求められている。我々はこれまでにMgFe<SUB>2</SUB>O<SUB>4</SUB>にCa<SUP>2+</SUP>を置換したMg<SUB>1-X</SUB>Ca<SUB>X</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系がきわめて優れた発熱能をもつ材料であることを発見し報告してきている。この材料がCa<SUP>2+</SUP>置換により発熱する理由として、800℃付近で焼成することによりMgFe<SUB>2</SUB>O<SUB>4</SUB>型立方晶からCaFe<SUB>2</SUB>O<SUB>4</SUB>型斜方晶へ相が変化し、これによる結晶の歪みが交流磁場中のヒステリシス損失をもたらすことを考えてきたが明確ではない。そこで、これまで行なってきた逆共沈法による作製以外に、有機溶媒を用いる新規方法によるMg<SUB>1-X</SUB>Ca<SUB>X</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系の作製を行ない、発熱特性および結晶構造との比較を行なった。
  • Yoneda Keiichi, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2009-  (0)  399  -399  2009  
    癌の新しい焼灼療法への応用を目的として交流磁場中において発熱能の優れた磁性材料が求められている。我々はこれまでにMgFe<SUB>2</SUB>O<SUB>4</SUB>にCa<SUP>2+</SUP>を置換したMg<SUB>1-x</SUB>Ca<SUB>x</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系がきわめて優れた発熱能をもつ材料であることを発見し報告してきている。この材料がCa<SUP>2+</SUP>置換により発熱する理由として、800℃付近で焼成することによりMgFe<SUB>2</SUB>O<SUB>4</SUB>型立方晶からCaFe<SUB>2</SUB>O<SUB>4</SUB>型斜方晶へ相が変化し、これによる結晶の歪みが交流磁場中のヒステリシス損失をもたらすことを考えてきたが明確ではない。そこで、これまで行なってきた逆共沈法による作製以外に、有機溶媒を用いる新規方法によるMg<SUB>1-x</SUB>Ca<SUB>x</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系の作製を行ない、発熱特性および結晶構造との比較を行なった。 結果として、X線回折によりMgFe<SUB>2</SUB>O<SUB>4</SUB>では立方晶からの相変化がみられなかったが、Ca置換させたMg<SUB>0.5</SUB>Ca<SUB>0.5</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>ではどちらの作製法もみられ、斜方晶へ相変化する温度がエチレングリコールで作製した試料の方が低く、最大のΔTとなる700℃付近に一致していた。これらの結果より、交流磁場中での温度上昇は、焼成による斜方晶から立方晶への相転位に関係している。
  • Moritani Takeshi, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Hirazawa Hideyuki  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2009-  (0)  2PB03  -2PB03  2009  
    癌の新しい焼灼療法への応用を目的として交流磁場中において発熱能の優れた磁性材料が求められている。我々はこれまでにMg<SUB>1-X</SUB>Ca<SUB>X</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系がきわめて優れた発熱能をもつ材料であることを発見し報告してきている。今回、新しい材料としてガーネット系Y<SUB>3-X</SUB>Gd<SUB>X</SUB>Fe<SUB>5</SUB>O<SUB>12</SUB>系フェライトを逆共沈法により作製し、その結果、この系が高い発熱能を持つことを発見した。このGd<SUP>3+</SUP>置換により磁気モーメントが高まり発熱特性が高まることを期待したがX=0~2.5についてはほとんど同じ結果であり、1100℃付近で焼成した材料が最も発熱特性が優れていた。
  • 平澤英之, 青野宏通, 猶原隆, 前原常弘, 佐藤充則, 渡部祐司  材料の科学と工学  45-  (6)  236  -241  2008/12
  • 西岡光輝, 青野宏通, 猶原隆, 前原常弘, 平澤英之, 松友真哉  日本金属学会講演概要  143rd-  236  2008/09
  • 小山貴司, 青野宏通, 猶原隆, 前原常弘, 平澤英之, 松友真哉  日本金属学会講演概要  143rd-  237  2008/09
  • 佐藤充則, 吉田素平, 前原常弘, 平澤英之, 猶原隆, 渡部祐司, 青野宏通, 河内寛治  Drug Delivery System  23-  (3)  398  2008/06
  • 平澤英之, 青野宏通, 猶原隆, 前原常弘  軽金属学会大会講演概要  114th-  23  -24  2008/04
  • 佐藤充則, 吉田素平, 山本祐司, 前原常弘, 平澤英之, 猶原隆, 渡部祐司, 青野宏通, 河内寛治  Thermal Medicine  24-  (Supplement)  184  2008
  • Sasaki Hiroomi, Aono Hiromichi, Hirazawa Hideyuki, Naohara Takashi, Maehara Tsunehiro  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2008-  (0)  294  -294  2008  
    我々はこれまでの研究で、一般的に交流磁場焼灼法において有効とされてきたFeFe2O4と比べて、MgFe<SUB>2</SUB>O<SUB>4</SUB>がより優れた発熱特性をもつ材料であることを発見した。また、微粒子化が及ぼす交流磁場中での発熱特性の影響は、材料の磁区構造と深いかかわりがあると考えられる。一般的に、粒子が単磁区構造を示すまで微小化することによって、磁極に発生する静磁エネルギーが最大値となる。つまり微小化することでヒステリシス損失が増大し、発熱特性が向上すると考えられる。そこで、ビーズミルを用いてMgFe<SUB>2</SUB>O<SUB>4</SUB>の物理的粉砕による微粒子化を試みた。また、FeFe<SUB>2</SUB>O<SUB>4</SUB>についても比較検討した。
  • Sasaki Kenji, Aono Hiromichi, Hirazawa Hideyuki, Naohara Takashi, Maehara Tsunehiro, Sato Mitsunori  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2008-  (0)  296  -296  2008  
    新たに確立しようとしている癌の熱凝固療法は、磁性微粒子を癌細胞へ留置し交流磁場を加えることにより試料を発熱させ、癌細胞を熱凝固壊死させるというものである。そのとき磁性材料をリポソームなどのタンパク質で包埋し、血管に導入することを考えれば、発熱効率の良い微粒子材料が必要である。これまで市販のフェライトの中で最大の発熱を示したMgFe<SUB>2</SUB>O<SUB>4</SUB>に、イオン半径の大きいCa<SUP>2+</SUP>イオンを置換させた場合、著しい発熱特製の向上がみられた。癌治療に応用するには粒子径数十nm程度まで微粒子化する必要があることから、本研究では、 MgMg<SUB>0.5</SUB>Ca<SUB>0.5</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>を800度で焼成した試料についてビーズミルを用いて物理的粉砕による微粒子化と、発熱特性との関係を検討した。
  • 内原高大, 平澤英之, 楢原隆, 青野宏通, 平岡耕一, 野村信福, 前原常弘  日本金属学会講演概要  141st-  188  2007/09
  • 平澤英之, 青野宏通  ホソカワ粉体工学振興財団年報  (14)  212  -213  2007/05
  • 内原高大, 平澤英之, 平岡耕一, 青野宏通, 猶原隆, 前原常弘, 野村信福, 渡部祐司  日本金属学会講演概要  139th-  316  2006/09
  • Hirazawa Hideyuki, Ochi Takayuki, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2006-  (0)  603  -603  2006  
    新たに確立しようとしている癌の熱凝固療法は、磁性微粒子を癌細胞へ留置し、交流磁場により磁性体を発熱させ、癌細胞を熱凝固壊死させるというものである。現在、その方法に最も適した材料としてFeFe<SUB>2</SUB>O<SUB>4</SUB>が主に検討されているが、我々は固相反応法により作製されたMgFe<SUB>2</SUB>O<SUB>4</SUB>の方が発熱特性が優れ、なおかつ安定な材料であることを報告している。本研究では様々な方法(逆共沈法、グリコサーマル法、固相反応法)でMgFe<SUB>2</SUB>O<SUB>4</SUB>を作製し、結晶子や粒子径が発熱特性に及ぼす影響を検討した。その結果、MgFe<SUB>2</SUB>O<SUB>4</SUB>では粒子成長により発熱特性が向上するが、Ca<SUP>2+</SUP>を置換をしたものは異なる挙動を示すことがわかった。
  • Hirazawa Hideyuki, Kusamoto Satoshi, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Watanabe Yuji, Mori Kensaku, Hattori Yasumasa  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2006-  (0)  604  -604  2006  
    MgFe<SUB>2</SUB>O<SUB>4</SUB>について交流磁場下で最も優れた発熱特性を示すことを報告してきたが、最近、MgFe<SUB>2</SUB>O<SUB>4</SUB>にイオン半径の大きいCa<SUP>2+</SUP>イオンを置換させたMg<SUB>1-X</SUB>Ca<SUB>X</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系フェライトの前駆体粉末を逆共沈法により作製し、様々な焼成温度で作製した試料について検討したところ、X=0の試料については交流磁場下(370kHz, 1.77kA/m)であまり発熱しなかったが、Ca<SUP>2+</SUP>置換によりMgFe<SUB>2</SUB>O<SUB>4</SUB>を凌ぐほど発熱特性は向上することが明らかになった。特にX=0.5_から_0.8の範囲で、焼成温度300℃及び800℃の試料については非常に高い発熱特性を示した。この発熱特性はほぼヒステリシス損失による。
  • Development of Needle-shaped Ferrite Materials for High-frequency Inductive Ablation of Cancer
    Annual Journal of Engineering  5-  74  -78  2006
  • Developnent of the High-Frequency nductive Therapy for Liver Cancer with Ferrite Materials - A Cooperative Approachfrom Medical, Physical and Engineering Fields-
    The Japan Institute for MetalsMateria Japan  45-  (09)  664  -669  2006
  • Aono Hiromichi, Hirazawa Hideyuki, Naohara Takashi, Sadaoka Yoshihiko, Maehara Tsunehiro, Watanabe Yuuji  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2005-  (0)  739  -739  2005  
    新しい癌治療の方法として熱凝固療法が注目され、その発熱材料として交流磁場で発熱するフェライトの使用が検討されている。今回、Mg<SUP>2+</SUP>をCa<SUP>2+</SUP>に置換したMg<SUB>1-x</SUB>Ca<SUB>x</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB>系フェライトがこれまで報告されてきたマグネタイトなどの磁性材料と比べてもかなり大きく発熱することを見いだした。このフェライトは、作製方法の違いが発熱特性へ強く影響する。前駆体を逆共沈法にて作製し、それを様々な温度で焼成することにより上記フェライトを作製し、その粒子径や結晶サイズの影響、ヒステレシス損の影響などについて検討した。
  • Aono Hiromichi, Hirazawa Hideyuki, Ochi Takayuki, Naohara Takashi, Maehara Tsunehiro, Kikkawa Hiroyuki, Watanabe Yuji  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2004-  (0)  597  -597  2004  
    AC磁場中で発熱する材料は、癌の熱凝固療法に用いることを目的として、より発熱特性の優れた材料が求められている。これまでに、この材料としてFeFe2O4の使用が検討されてきた。本研究では様々な市販のフェライトMFe2O4, (M=Mg,Ni, Mn, Cu, Co, Fe, Sr)粉末のAC磁場下での発熱特性について検討した。市販の各種フェライト粉末1gを交流磁場中に置き、370kHz、4kA/mのAC磁場中で1gの試料粉末の温度を測定したところ、MgFe2O4が最も発熱特性が優れており、80℃まで昇温した。また、周波数や磁場の大きさに対する影響についても検討した。この発熱については、ヒステレシス損失により起こっていることが明らかになった。また、共沈法により作製したMgFe2O4についても検討した。
  • Aono Hiromichi, Hirazawa Hideyuki, Ochi Takayuki, Naohara Takashi, Maehara Tsunehiro, Kikkawa Hiroyuki, Watanabe yuji, Mori Kensaku, Hattori Yasumasa  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2004-  (0)  598  -598  2004  
    癌治療の方法として、熱凝固療法が注目され、その発熱材料として交流磁場で発熱するフェライトが知られている。今回、共沈法によりCaを含むMg1-xCaxFe2O4系フェライト微粒子を作製し、そのAC磁場下における発熱特性を検討したところ、これまでにないきわめて優れた発熱特性が得られた。すなわち、Caを含まないものは共沈法で作製した場合、発熱は小さいが、x=0.3以上ではこれまで報告されてきた材料よりも優れた発熱特性が得られた。この優れた発熱を示す材料は特定の温度の焼成により得られ、それ以外の温度で焼成した材料については発熱量が小さかった。その理由を検討するために、粒子径や結晶サイズの影響、ヒステレシス損の影響などについて検討した。
  • Hirasawa Hideyuki, Yano Jun, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Konishi Kensuke, Kamimori Tatsuo, Watanabe Yuji  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2003-  (0)  539  -539  2003  
    Fine MgFe<sub>2</sub>O<sub>4</sub> ferrite powder for local hyperthermia was synthesized by a glycothermal method. The single phase of MgFe<sub>2</sub>O<sub>4</sub> powder was obtained when the precursor decomposed above 800&deg;C which was confirmed by TGA and XRD. The temperature enhancement by AC magnetic field was increased with an increase in the particle size for the MgFe<sub>2</sub>O<sub>4</sub> ferrite powder.
  • Yano Jun, Hirasawa Hideyuki, Aono Hiromichi, Naohara Takashi, Maehara Tsunehiro, Konishi Kensuke, Kamimori Tatsuo, Watanabe Yuji  Preprints of Annual Meeting of The Ceramic Society of Japan
    Preprints of Fall Meeting of The Ceramic Society of Japan  2003-  (0)  538  -538  2003  
    Recently, hyperthermia has been expected for a treatment of cancer tissues. In this case, the heating of cancer tissues keeps at about 42&deg;C using AC magnetic field, since the heating at this temperature affects only the cancer cells and does not give a damage to normal cells. Heating properties under AC magnetic field were investigated for various ferrite powders. The maximum temperature was obtained when a frequency of AC magnetic field was about 370 kHz for all the samples examined. Mg-ferrite (MgFe<sub>2</sub>O<sub>4</sub>) showed the excellent temperature ehnancement compared with those of other ferrites.
  • H AONO, E SUGIMOTO, Y SADAOKA, N IMANAKA, GY ADACHI  JOURNAL OF THE ELECTROCHEMICAL SOCIETY  136-  (2)  590  -591  1989/02  Introduction scientific journal

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Research Grants & Projects

  • 陰イオン交換能力を付加したハイブリッドゼオライトの開発
    科学研究費補助金:基盤研究(C)
    Date (from‐to) : 2020/04 -2023/03
  • ナノメディシンを用いた温熱・免疫療法による腹膜播種の新規治療戦略
    科学研究費補助金:(基盤研究(C))
    Date (from‐to) : 2015/04 -2018/03 
    Author : 岸本 浩行
  • 農業に革新をもたらす光合成用スペクトルコンバータの開発
    科学研究費補助金(基盤研究(B))
    Date (from‐to) : 2015/04 -2018/03 
    Author : 松枝 直人
  • 福島の汚染土壌からの放射性核種除染技術の実用化
    科学研究費補助金(基盤研究(A))
    Date (from‐to) : 2014/06 -2018/03 
    Author : 青野 宏通
  • 放射性セシウム除染を目的としたゼオライト-マグネタイト複合材料の開発
    科学研究費補助金(挑戦的萌芽研究)
    Date (from‐to) : 2013/04 -2015/03 
    Author : 青野 宏通
  • 放射能汚染土壌の除染実用化技術の開発
    環境省「環境研究総合推進費」
    Date (from‐to) : 2013 -2014 
    Author : 逸見彰男
  • 優れた発熱能と生体適合性を有する磁性材料の開発と作製法の確立
    科学研究費補助金(基盤研究(B))
    Date (from‐to) : 2009/04 -2012/03 
    Author : 青野 宏通
  • 金属-金属酸化物複合針状材料の発熱機構の解明と応用
    科学研究費補助金(萌芽研究→挑戦的萌芽研究)
    Date (from‐to) : 2007/04 -2009 
    Author : 青野 宏通
  • 希土類ガーネット系磁性材料の微粒子化と焼灼療法への応用
    JSTシーズ発掘試験研究
    Date (from‐to) : 2009 
    Author : 青野 宏通
  • 塞栓用球状フェライトの低温における作製
    JSTシーズ発掘試験研究
    Date (from‐to) : 2008 
    Author : 青野 宏通
  • 新規金属-金属酸化物複合針状材料の最適化
    JSTシーズ発掘試験研究
    Date (from‐to) : 2006 
    Author : 青野 宏通
  • 医療への応用を目指した新規フェライト微粒子材料の開発
    JSTシーズ育成試験研究
    Date (from‐to) : 2005 
    Author : 青野 宏通
  • 交流磁場中で著しく発熱する新規MgCa系フェライト微粒子材料の作製と応用
    マツダ研究助成金
    Date (from‐to) : 2005 
    Author : 青野 宏通
  • ガラス固体電解質により参照電極を密閉した新しいガスセンサの開発
    科学研究費補助金(奨励研究(A)→若手研究(B))
    Date (from‐to) : 2001 -2002 
    Author : 青野 宏通
  • 高緻密アルカリイオン伝導体の開発と低濃度用塩素ガスセンサへの応用
    マツダ研究助成金
    Date (from‐to) : 1998 
    Author : 青野 宏通
  • 高塩化物イオン伝導性ガラスの開発と塩素ガスセンサへの応用
    科学研究費補助金(奨励研究(A))
    Date (from‐to) : 1996 
    Author : 青野 宏通
  • リチウムクロムリン酸複合塩固体電解質における高リチウムイオン伝導相の合成
    科学研究費補助金(奨励研究(A))
    Date (from‐to) : 1995 
    Author : 青野 宏通
  • リチウムチタンリン酸複合塩固体電解質を用いた全固体リチウム電池の基礎的研究
    科学研究費補助金(奨励研究(A))
    Date (from‐to) : 1994 
    Author : 青野 宏通
  • 積層NASICON型固体電解質を用いたリチウム電池の開発
    科学研究費補助金(奨励研究(A))
    Date (from‐to) : 1994 
    Author : 青野 宏通
  • リチウムチタンリン酸複合塩固体電解質の低温における電気的特性
    科学研究費補助金(奨励研究(A))
    Date (from‐to) : 1992 
    Author : 青野 宏通
  • リチウムチタンリン酸復合塩固体電解質の電池材料への応用
    科学研究費補助金(奨励研究(A))
    Date (from‐to) : 1991 
    Author : 青野 宏通
  • Perovskite-type oxide prepared form Heteronuclear complex
  • Study on Chlorine Gas Sensor
  • 結晶質-非晶質複合塩化物イオン伝導体の開発と塩素ガスセンサへの応用
    科学研究費補助金(奨励研究(A))
    Author : 青野 宏通

Social Contribution

  • 土壌除染用の“磁石で回収できる 機能性ゼオライト”開発
    Date (from-to) : 2016/10/30-2016/10/30
    Role : Lecturer
    Sponser, Organizer, Publisher  : 愛媛大学工業会
    Event, Program, Title : 東京支部講演会
  • 機能性を有するゼオライトの合成と応用(除染材料および蛍光材料を例として)
    Date (from-to) : 2015/09/04-2015/09/04
    Role : Lecturer
    Sponser, Organizer, Publisher  : 中国・四国地区国立大学法人等技術職員研修
  • 福島の除染を目的とした磁性化ゼオライトの研究
    Date (from-to) : 2014/11/22-2014/11/22
    Role : Lecturer
    Sponser, Organizer, Publisher  : 愛媛大学工業会
    Event, Program, Title : 近畿支部

Media Coverage

  • 機能材料について
    Date : 2013/10/12
    Publisher, broadcasting station: 南海放送
    Program, newspaper magazine: 研究室からこんにちは!
    Media report
  • 福島の農地をよみがえらせる!世界初の除染技術 “廃棄物+磁力”で放射性物質を除去する!
    Date : 2013/06/09
    Publisher, broadcasting station: TBS
    Program, newspaper magazine: 夢の扉+
    Media report

Others

  • 2003/10 -2003/10 衛生工学衛生管理士資格取得

愛媛大学教員活動実績

教育活動(B)

担当授業科目(B01)

  • 2019, the first semester, under graduate, 新入生セミナーA
  • 2019, the first semester, under graduate, 化学実験
  • 2019, the first semester, under graduate, 無機材料化学
  • 2019, the first semester, under graduate, セラミックス材料学
  • 2019, the first semester, under graduate, 基礎化学概論
  • 2019, the first semester, under graduate, 基礎物理化学
  • 2019, the first semester, under graduate, 化学基礎Ⅰ
  • 2019, the first semester, under graduate, 化学基礎Ⅱ
  • 2019, the first semester, under graduate, 工学リテラシーⅡ
  • 2019, the first semester, under graduate, 基礎安全学
  • 2019, the first semester, master course, 安全衛生管理特別講義


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