JaLCDOI 10.18926/fest/11645
Title Alternative Selective reduction of nitrogen oxide with propylene on alumina-zirconia prepared from Al chelate compound and Zr alkoxide
FullText URL 001_199_204.pdf
Author Kawabata, Koji| Yoshimatsu, Hideyuki| Yabuki, Tatsumi| Osaka, Akiyoshi| Miura, Yoshinari|
Abstract An alumina-zirconia (AZ) composite powder was prepared by thermal decomposition of the organic precursors, which were synthesized from ethyl acetoacetate aluminium diisopropylate and zirconium n-butoxide. Specific surface area of AZ was higher than that of alumina-zirconia (ALK) prepared from aluminium sec-butoxide and zirconium nbutoxide. True density of AZ was lower than that of ALK. Selective reduction of nitrogen oxide with propylene in oxygen-rich atmosphere on AZ was superior to that on ALK.
Keywords Al chelate compound Zr alkoxide alumina-zirconia specific surface area true density selective reduction of nitrogen oxide
Publication Title 岡山大学環境理工学部研究報告
Published Date 1996-03
Volume volume1
Issue issue1
Start Page 199
End Page 204
ISSN 1341-9099
language 日本語
File Version publisher
NAID 110002291536
JaLCDOI 10.18926/15459
FullText URL Mem_Fac_Eng_OU_23_1_31.pdf
Author Miura, Yoshinari| Yuasa Motokazu| Osaka, Akiyoshi| Takahashi, Katsuaki|
Abstract Sodium borosilicate gels of compositions similar to that of Vycor(R) glass like 80SiO(2).15B(2)O(3).5Na(2)O(wt%) were prepared from hydrolysis and polycondensation of tetraethyl orthosilicate, trimethyl borate, and sodium methylate under the HCl catalysis. Variation of the gelation time is examined as a function of the mixing ratio of the starting materials and the catalyst. The thermal behavior of the gels has been discussed on the basis of their TG and DTA traces.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1988-11-22
Volume volume23
Issue issue1
Start Page 31
End Page 38
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307464
JaLCDOI 10.18926/15462
FullText URL Mem_Fac_Eng_OU_23_1_39.pdf
Author Osaka, Akiyoshi| Yuasa Motokazu| Miura, Yoshinari| Takahashi, Katsuaki|
Abstract Sodium borosilicate gels of compositions similar to that of Vycor(R) glass like 80SiO(2).15B(2)O(3).5Na(2)O (wt%) were prepared from hydrolysis and polycondensation of metal alkoxides under the HCl catalysis. Variation of specific surface area and porosity with temperature indicated that closed pores were opened below 400℃, and collapsed above 450℃ after the porosity reached a maximum value around 450℃. The structural evolution was examined due to IR spectra and a phase separation in the gels was observed. The solubility of the gels into 1N-HCl was studied as a function of the treatment temperature.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1988-11-22
Volume volume23
Issue issue1
Start Page 39
End Page 48
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307518
JaLCDOI 10.18926/19677
FullText URL Mem_Fac_Eng_OU_33_2_79.pdf
Author Osaka, Akiyoshi| Hayakawa, Satoshi| Koyano Keiko| Tsuru, Kanji|
Abstract A titanium oxide gel was electrochemically prepared on Ti with a cell consisting of Ti as the working electrode, Pt as the counter one, AgCl as the reference one, and an aqueous solution of 0.1 mol/L Ca(NO(3))(2) as the electrolyte solution. The Ti electrode was kept at 9.5V for 1 hr for oxidation and subsequently kept at-3.0V for 10 min (Ca9.5-3.0):calcium ions were expected to be adsorbed at the latter treatment. Other Ti specimen was kept at -3.0V for 10 min (Ca-3.0). Both specimens were found so bioactive as to deposit apatite in 12 hr (Ca9.5-3.0) and in 1 day (Ca-3.0) when soaked in a simulated body fluid (Kokubo solution). Calcium carbonate detected on the surface of Ca9.5-3.0 caused no harmful effects on spontaneous deposition of apatite in the fluid.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1999-04-27
Volume volume33
Issue issue2
Start Page 79
End Page 84
ISSN 0475-0071
language 日本語
File Version publisher
NAID 120002309011
JaLCDOI 10.18926/19596
FullText URL Mem_Fac_Eng_OU_31_2_45.pdf
Author Osaka, Akiyoshi| Kobayashi Keizo| Hayakawa, Satoshi| Ohtsuki, Chikara|
Abstract The thermal expansion coefficient of some bioactive glasses in the system CaO-SiO(2)-B(2)O(3) were adjusted to be similar to that of titanium by controlling the composition. A glass of composition 45CaO・30SiO(2)・25B(2)O(3) was selected among those as the enameling glass. A slurry was prepared by mixing the glass powder and ethanal to be developed on titanium and heated at 740℃ for 30 min. Thus treated specimen was soaked in a simulated body fluid (Kokubo solutiion). FT-IR reflection and thin film X-ray diffraction analyses indicated apatite formation on the glass coating layer within 12 h of soaking in the fluid. Thus titanium could be provided with bioactivity due to the enameling.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 45
End Page 51
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309181
JaLCDOI 10.18926/19594
FullText URL Mem_Fac_Eng_OU_31_2_39.pdf
Author Imayoshi Naoki| Hayakawa, Satoshi| Ohtsuki, Chikara| Osaka, Akiyoshi|
Abstract Nb(2)O(5)-and Ta(2)O(5)-doped calcium si1icate glasses were soaked for various periods in a simulated body fluid(Kokubo solution) up to 30 days. Apatite formation ability of the surface of these glasses were investigated with thin-film X-ray diffraction and FT-IR reflection spectroscopy. The effects of these additive oxides on the bioactivity of CaO・SiO(2) based glass were discussed. A small amount of Nb(2)O(5) and Ta(2)O(5) suppressed the rate of silica hydrogel layer formation and the apatite formation on the surface of the glasses. The rate of the apatite nucleation on the surface of Nb(2)O(5)-doped calcium silicate glass was slower than that on the surface of Ta(2)O(5)-doped calcium silicate glass. It was concluded that the decrease in the apatite forming ability of calcium silicate glasses by these additive oxides is attributed to the suppression of formation of silica hydrogel layer which plays an important role in apatite nucleation.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1997-03-28
Volume volume31
Issue issue2
Start Page 39
End Page 44
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002309151
JaLCDOI 10.18926/15464
FullText URL Mem_Fac_Eng_OU_28_2_77.pdf
Author Osaka, Akiyoshi| Kawamura Haruyuki| Miura, Yoshinari|
Abstract Amorphous films of lead oxyfluorosilicate were prepared with a rf-sputtering technique, and the distribution profiles of the component elements and chemical states of the fluoride ions were analyzed with an X-ray photoelectron spectrometer. Si atoms with an expanded coordination, O(4)Si-F, were present near the surface, and O(3)Si-F units were present in the deeper part of the films. Electrical resistance indicated transition to a conduction state for the films containing fluoride ions, while the films were crystallized to precipitate low quartz by the irradiation of He-Ne laser of 3 mW up to 1 sec.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1994-03-15
Volume volume28
Issue issue2
Start Page 77
End Page 84
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307766
JaLCDOI 10.18926/15363
FullText URL Mem_Fac_Eng_OU_34_39.pdf
Author Hayakawa, Satoshi| Shirosaki, Yuki| Yabuta, Takeshi| Tsuru, Kanji| Ohtsuki Chikara| Osaka, Akiyoshi|
Abstract Silicone elastomer was chemically treated at 60℃ for 7 days with 30 wt% H(2)O(2) solutions with or without TaCl(5) and soaked for various periods in a simulated body fluid(Kokubo solution) up to 21 days. Apatite formation ability of the surface of the silicone elastomer specimens was investigated with thin-film X-ray diffraction and FT-IR reflection spectroscopy. These silicone specimens did not deposit apatite or calcium phosphates, irrespective of chemical treatment. Osteoblast-like cells (MC3T3-El) derived from mouse were cultured on the specimens at 36.5℃ under 5%C0(2) and 95% humidity. Similar degree of proliferation of cells was observed at 7 days among three specimens, while the no treatment specimen after incubation for 5 days showed a lower degree of proliferation than the silicone treated with 30 wt% H(2)O(2) solutions with or without TaCl(5). Alkaline phosphatase activity of the cells proliferated on the no treatment specimen was lower than those of the silicone treated with 30 wt% H(2)O(2) solutions with or without TaCl(5). These results indicate that the cytotoxicity of the silicone could be improved by the chemical treatment with 30 wt% H(2)O(2) solutions with or without TaCl(5).
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2000-03-27
Volume volume34
Issue issue1-2
Start Page 39
End Page 43
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308019
JaLCDOI 10.18926/15428
FullText URL Mem_Fac_Eng_OU_29_2_83.pdf
Author Tsuru, Kanji| Nishiyama Chikako| Ohtsuki, Chikara| Osaka, Akiyoshi|
Abstract One of the CaO,SiO(2)-based bioactive glasses(5OCaO・ 5OSiO (2) in mol%) were soaked for various periods in a simulated body fluid(SBF) with or without containing alcohols such as methanol, ethanol, and 1-propanol. Effect of the alcohols was investigated on the apatite formation on the glass surface with thin-film X-ray diffraction, FT-IR reflection spectroscopy and scanning electron microscopy. Under the presence of alcohols up to 0.1mol/l in the SBF an apatite layer was formed on the glass, while it consisted of crystallites similar in morphology but larger in size than that found for the SBF without the alcohols. It was concluded that the alcohols little influenced the the apatite forming ability of the CaO,SiO(2)-based glasses.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-03-27
Volume volume29
Issue issue2
Start Page 83
End Page 88
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307301
JaLCDOI 10.18926/47005
FullText URL mfe_36_1_117_121.pdf
Author Shirosaki, Yuki| Tsuru, Kanji| Hayakawa, Satoshi| Osaka, Akiyoshi| Takashima, Seisuke|
Abstract γ-Methacryloxypropyltrimethoxysilane (γ-MPS) was grafted to silicone due to emulsion polymerization to induce Si-OH groups, in order to provide silicone with bioactivity spontaneous deposition of apatite in body fluid and to improve cytocompatibility. Apatite deposited on the grafted silicone within 7 days of soaking in 1.5 times as concentrated as the Kokubo solution. Osteoblastic cells (MC3T3-E1) were cultured on the specimens up to 7 days. After 5 days of culture, the number of MC3T3-E1 cells on the grafted specimen was much greater than that on the original specimen. These results indicated that the biocompatibility of silicone elastomer was improved by the grafting γ-MPS.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2001-12
Volume volume36
Issue issue1
Start Page 117
End Page 121
ISSN 0475-0071
language 英語
File Version publisher
NAID 120003497031
JaLCDOI 10.18926/15436
FullText URL Mem_Fac_Eng_OU_26_2_69.pdf
Author Fujii, Tatsuo| Sakata Naoki| Nanba, Tokuro| Osaka, Akiyoshi| Miura, Yoshinari| Takada, Jun|
Abstract (001)-oriented Ti(2)O(3) films were epitaxially grown on a(001)-face of sapphire single-crystalline substrate by an activated reactive evaporation method. The formation ranges of stoichiometric and nonstoichiometric Ti(2)O(3) films were determined as a function of the substrate temperature (Ts), the oxygen pressure (Po(2)) and the deposition rate. Stoichiometric Ti(2)O(3) films were grown at Ts≧673K under Po(2)≧1.0×10(-4)Torr, which showed the metal-insulator transition with a sharp change in electrical resistivity from 3.5×10(-2) to 2.6×10(-3)Ωcm at 361K. Nonstoichiometric films prepared under less oxidized conditions did not exhibit the transition. The nonstoichiometry of the Ti(2)O(3)films was discussed in terms of excess Ti ions.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 69
End Page 75
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307639
JaLCDOI 10.18926/15473
FullText URL Mem_Fac_Eng_OU_26_2_61.pdf
Author Osaka, Akiyoshi| Kawabata Kouji| Nanba, Tokuro| Takada, Jun| Miura, Yoshinari|
Abstract Mullite-dispersed silica ceramics were prepared through sol-gel processing by the use of tetraethoxy silane, aluminium nitrate and aluminium isopropoxide as the Si and Al sources where HCl and HN0(3) were the catalyst. Effect of the starting materials, solvents and catalysts was examined on the gelation time or temperature of mullite precipitation. Apparent activation energy of gelation ranged from 80 to 95kJ/mol. The presence of AI in the sols elongated the gelling time suggesting the formation of chelate bonds between AI and Si-OR or Si-OH bonds.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1992-03-28
Volume volume26
Issue issue2
Start Page 61
End Page 67
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307416
JaLCDOI 10.18926/15486
FullText URL Mem_Fac_Eng_OU_25_1_23.pdf
Author Miura, Yoshinari| Takada, Jun| Osaka, Akiyoshi| Kawamura, Toshio|
Abstract Zinc oxide films were prepared on silica glass substrates by the use of an r.f. activated reactive evaporation (ARE) method, and were examined by X-ray diffraction (XRD) and scanning electron micrograph (SEM). XRD measurements indicate that the films were c-axis oriented and that an r.f. plasma of Zn and O was necessary for the ZnO film deposition. Substrate temperature, oxygen gas pressure, evaporation rate, r.f. power and inlet position of oxygen gas effect the c-axis orientation, the growth rate and the microstructure of the films. Optimum conditions for a dense film with a fine texture of the surface and having good crystallinity were as follows: the substrate temperature;400℃, the evaporation rate;5.0(A)/s, the oxygen pressure;2.0x10(-4) Torr, the r.f. power;150 to 200W, and the oxygen gas inlet near the substrate. For the film prepared under the optimum conditions, the standard deviation σ of the rocking curve for the (002) diffraction was 1.9deg, smaller than that of the film prepared by using an r.f. sputtering method.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1990-12-14
Volume volume25
Issue issue1
Start Page 23
End Page 35
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307600
JaLCDOI 10.18926/47027
FullText URL mfe_36_2_067_072.pdf
Author Yoshioka, Tomohiko| Tsuru, Kanji| Hayakawa, Satoshi| Osaka, Akiyoshi|
Abstract Alginic acid was immobilized on γ-aminopropyltriethoxysilane-coated glass as a model substrate since an alginic acid layer was known to prevent cell adhesion. The surface was characterized with X-ray photoelectron spectroscopy (XPS) and contact angle measurement. The coated substrates adsorbed practically no calcium phosphates on their surfaces when soaked in a simulated body fluid (SBF) of Kolrubo recipe. Since calcium ions are one of the factors for blood clotting, the present alginic acid coating is one of the candidates to improve blood compatibility of clinical materials.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2002-03
Volume volume36
Issue issue2
Start Page 67
End Page 72
ISSN 0475-0071
language 英語
File Version publisher
NAID 80015582225
JaLCDOI 10.18926/15474
FullText URL Mem_Fac_Eng_OU_24_1_53.pdf
Author Osaka, Akiyoshi| Takao Seiji| Oda, Kiichi| Takada, Jun| Miura, Yoshinari|
Abstract Electrical resistance and X-ray photoelectron depth profile analysis are studied for antimony doped tin oxide films developed on silica, alkali-free and sodalime slide glass substrates. The sodium ions diffused from the substrates to the films prevented the crystal growth of rutile type tin oxide in the film, resulting in the high electrical resistance. A diffusion layer has been detected for each film with diffuse profiles of multi valent cations (Sn, Si or Ca) at the interface of the tin oxide film and substrate. A greater amount of sodium atoms have been detected in the film developed on the soda-lime glass while almost no sodium atoms have been found in those on the other substrates. This can be explained by the diffusion of the sodium ions in the substrate due to a drastic hydronium-sodium exchange mechanism under highly acidic conditions during the dipping and drying processes.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1989-11-29
Volume volume24
Issue issue1
Start Page 53
End Page 61
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307279
JaLCDOI 10.18926/15426
FullText URL Mem_Fac_Eng_OU_29_2_77.pdf
Author Tsuru, Kanji| Nishiyama Chikako| Ohtsuki, Chikara| Osaka, Akiyoshi|
Abstract Poly(methyl methacrylate) substrates were immersed in suspensions containing bioactive 50CaO・50SiO(2) (mol%) glass particles (45 μm in diameter) and a 6:4 (volume fraction) mixture of ethanol and THF, and an ultrasonic energy was applied to the system. A layer of glass particles was implanted and covered more than 50% of the substrate surface. Thin film X-ray diffraction patterns and FT-IR reflection spectra indicated deposition of apatite on the glass-implanted substrates after they were soaked for 12 h in a simulated body fluid similar in apatite-deposition ability to the human blood plasma. Flake-like apatite crystallites formed on the substrate soaked in SBF for 3 days.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 1995-03-27
Volume volume29
Issue issue2
Start Page 77
End Page 81
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002307332
Author Osaka, Akiyoshi|
Published Date 1991-12
Publication Title 環境制御
Volume volume13
Content Type Others
Author Osaka, Akiyoshi|
Published Date 1995-12-20
Publication Title 環境制御
Volume volume17
Content Type Others