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121.
122.
Atsushi Hibi 《Thin solid films》2008,516(5):856-858
Gaseous copper chlorides can be employed as precursors in a newly developed Cu-CVD method called metal chloride reduction-chemical vapor deposition (MCR-CVD). More than one species exists in the gas phase of copper chloride. We studied the gas phase composition of copper chlorides generated by etching of copper surface by electron impact-mass spectrometry. The composition of gaseous species can change because of gas phase reactions. After desorbing from the copper surface, copper chloride reached equilibrium composition immediately. 相似文献
123.
Masazumi Godo Masatsune Umemura Atsushi Ishihara Toshiaki Kabe 《American Institute of Chemical Engineers》1997,43(11):3105-3110
To determine the behavior of hydrogen in tetralin, the reaction of tetralin with tritiated gaseous hydrogen was studied in a flow reactor at 400–450°C, 2.5–9.8 MPa for various residence times. The amount of hydrogen exchange between tetralin and tritiated hydrogen was estimated from the balance of hydrogen and tritium. Although yields of methylindan and naphthalene, and the hydrogen-exchange ratio (HER) of tetralin increased monotonously with residence time, these values were scarcely influenced by the reaction pressure at every temperature. It was thought that the formation of tetralyl radicals in this system would be the rate-determining step for both the conversions of tetralin into methylindan and naphthalene, and the hydrogen exchange of tetralin. Conversions of tetralin into methylindan and naphthalene, and the hydrogen-exchange reaction using the autoclave were very close to those using the flow reactor. 相似文献
124.
Takashi Tatsumi Shigeki Kunitomi Jun Yoshiwara Atsushi Muramatsu Hiro-o Tominaga 《Catalysis Letters》1989,3(3):223-226
In the reaction of CO-H2-NH3 on Mo/SiO2 catalysts, HCN is formed and is considered to be the principal intermediate for the formation of CH3CN. At low temperature methylamine is also formed. 相似文献
125.
Syuji Fujii Yukihiro Nishimura Atsushi Aichi Soichiro Matsuzawa Yoshinobu Nakamura Kensuke Akamatsu Hidemi Nawafune 《Synthetic Metals》2010,160(13-14):1433-1437
Polyaniline–silver nanocomposites were synthesized in the form of colloidal particles by the facile one-step aqueous chemical oxidative dispersion polymerization of aniline using silver nitrate as an oxidant and poly(vinyl alcohol) as a colloidal stabilizer. Aniline monomer was oxidized by silver ions, yielding polyaniline and elemental Ag simultaneously. The synthesized nanocomposite particles were colloidally stable over 2 years and transmission electron microscopy studies indicated the production of spherical, plate and rod-shaped polyaniline–silver nanocomposite particles with a silver core–polyaniline shell morphology. The conductivity of a pressed pellet of the nanocomposite particles using the conventional four-point probe technique was 1.4 × 10?2 S/cm at 25 °C. The nanocomposite particles behaved as a ‘colored’ particulate emulsifier for the stabilization of transparent oil-in-water emulsions. 相似文献
126.
Hiroki Nagasawa Akihiro Yamasaki Atsushi Iizuka Kazukiyo Kumagai Yukio Yanagisawa 《American Institute of Chemical Engineers》2009,55(12):3286-3293
Bipolar membrane electrodialysis is applied to CO2 recovery from alkaline carbonate solution. CO2 in flue gas is captured by an alkaline hydroxide absorbing solution to form an alkaline carbonate solution. The captured CO2 is recovered from the alkaline carbonate solution via bipolar membrane electrodialysis, and the alkaline solution is regenerated simultaneously. To reduce the power requirement for CO2 recovery, this study considers optimal design and operation. Three membrane arrangements were compared, and the results indicate the membrane arrangement comprising a bipolar membrane and cation exchange membrane is the most energy saving. With further optimization of operation conditions, the minimum power requirement for CO2 recovery was reduced to 2.1 MJ/kg‐CO2 (or 2.1 GJ/t‐CO2). © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
127.
Rare-earth (RE: Lu, Gd, Nd, 0.10 mol%)-doped alumina nanopowders were prepared by a new sol-gel route using polyhydroxoaluminum (PHA) and RECl3 solutions under α-alumina (∼ 75 nm) seeding. Among the rare-earth dopants studied, Lu yields the most suitable nanopowders for low-temperature densification. The 0.10 mol% Lu-doped nanopowders, which were obtained at a calcination temperature of 900 °C under 5 mass% α-alumina seeding, consisted of ∼ 80-nm α-alumina particles and γ-alumina nanoparticles. Using these Lu-doped alumina nanopowders, fully densified alumina ceramics with a uniform microstructure composed of fine grains with an average size of 0.61 μm could be obtained at 1400 °C by pressureless sintering. Clearly, the Lu-doped nanopowders obtained here represent a viable option for fabricating dense, finer-grained alumina ceramics because an undoped sample with 5 mass% seeds gave a microstructure with an average grain size of 1.78 μm at 1400 °C. 相似文献
128.
We have developed a novel electrolytic system for anodic acyloxylation based on the acid–base reactions between acetic acid or trifluoroacetic acid and solid-supported bases. On the basis of the electrolytic system, anodic acyloxylation of organic compounds, which even have considerably high oxidation potentials, was successfully carried out to provide the corresponding acyloxylated products in moderate to excellent yields. Furthermore, it was found that silica gel supported bases are not only chemically stable under acidic conditions but also electrochemically stable and thus reusable for many times. 相似文献
129.
130.
Yuki Totani Atsushi Sugino Toshiki Miyazaki Chikara Ohtsuki 《Materials science & engineering. C, Materials for biological applications》2010,30(4):624-630
Polymethylmethacrylate (PMMA)-based bone cement is widely used for the fixation of artificial joints. However, it is not considered a bioactive material because it lacks the ability to induce a direct bond with bone. In order to improve the long-term stability of cemented fixations, the development of bioactive bone cements is desirable. An essential requirement of a bioactive material includes the induction of bone-like apatite on its surface within the in vivo environment. Previously, we prepared bioactive PMMA-based bone cements by a modification with water-soluble calcium salts and alkoxysilane. Because spatial design may enhance apatite formation on bioactive material surfaces in vivo, we aimed to evaluate the effect of spatial design on apatite formation on modified PMMA-based bone cements in simulated body fluid (SBF). We found that an appropriate spatial design shortened the induction period for the apatite deposition on the modified bone cements. It is expected that osteoconduction would be enhanced in spontaneously created gap between the cement and the host bone leading to tight integration. 相似文献