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排序方式: 共有317条查询结果,搜索用时 15 毫秒
1.
2.
Masahiro Murayama Ryoji Kanno Michihiko IrieShinya Ito Takayuki HataNoriyuki Sonoyama Yoji Kawamoto 《Journal of solid state chemistry》2002,168(1):140-148
The new lithium ionic conductors, thio-LISICON (LIthium SuperIonic CONductor), were found in the ternary Li2S-SiS2-Al2S3 and Li2S-SiS2-P2S5 systems. Their structures of new materials, Li4+xSi1−xAlxS4 and Li4−xSi1−xPxS4 were determined by X-ray Rietveld analysis, and the electric and electrochemical properties were studied by electronic conductivity, ac conductivity and cyclic voltammogram measurements. The structure of the host material, Li4SiS4 is related to the γ-Li3PO4-type structure, and when the Li+ interstitials or Li+ vacancies were created by the partial substitutions of Al3+ or P5+ for Si4+, large increases in conductivity occur. The solid solution member x=0.6 in Li4−xSi1−xPxS4 showed high conductivity of 6.4×10-4 S cm−1 at 27°C with negligible electronic conductivity. The new solid solution, Li4−xSi1−xPxS4, also has high electrochemical stability up to ∼5 V vs Li at room temperature. All-solid-state lithium cells were investigated using the Li3.4Si0.4P0.6S4 electrolyte, LiCoO2 cathode and In anode. 相似文献
3.
Hideki Namba Okihiro Tokunaga Tadashi Tanaka Yoshimi Ogura Shinji Aoki Ryoji Suzuki 《Radiation Physics and Chemistry》1993,42(4-6):669-672
The fundamental research work with simulated coal-fired flue gas was performed in JAERI to get basic data for electron beam treatment of flue gas from thermal power plants in Japan. The standard condition of the experiments was set to be the same as that of next large scale pilot test in Nagoya. The concentrations of NOx and SOx were 225 ppm and 800 ppm, respectively. The temperature of the system was 65°C. The effect of multiple irradiation was observed for NOx removal. The target SOx and NOx removals (94% and 80%, respectively) with low NH3 leakage (less than 10 ppm) were achieved at 9 kGy irradiation with 0.9 NH3 stoichiometry during 7 hours continuous operation. The facility for the pilot plant (12,000 Nm3/hr) has just built at the site of Shin-Nagoya power plant of Chubu Electric Power Company and will be started in full operation in November 1992. 相似文献
4.
Evaluation of the disintegration time of rapidly disintegrating tablets via a novel method utilizing a CCD camera 总被引:6,自引:0,他引:6
Morita Y Tsushima Y Yasui M Termoz R Ajioka J Takayama K 《Chemical & pharmaceutical bulletin》2002,50(9):1181-1186
Many kinds of rapidly disintegrating or oral disintegrating tablets (RDT) have been developed to improve the ease of tablet administration, especially for elderly and pediatric patients. In these cases, knowledge regarding disintegration behavior appears important with respect to the development of such a novel tablet. Ordinary disintegration testing, such as the Japanese Pharmacopoeia (JP) method, faces limitations with respect to the evaluation of rapid disintegration due to strong agitation. Therefore, we have developed a novel apparatus and method to determine the dissolution of the RDT. The novel device consists of a disintegrating bath and CCD camera interfaced with a personal computer equipped with motion capture and image analysis software. A newly developed RDT containing various types of binder was evaluated with this protocol. In this method, disintegration occurs in a mildly agitated medium, which allows differentiation of minor distinctions among RDTs of different formulations. Simultaneously, we were also able to detect qualitative information, i.e., morphological changes in the tablet during disintegration. This method is useful for the evaluation of the disintegration of RDT during pharmaceutical development, and also for quality control during production. 相似文献
5.
Hiizu Iwamura Tadashi Sugawara Yuzo Kawada Kazuo Tori Ryonosuke Muneyuki Ryoji Noyori 《Tetrahedron letters》1979,20(36):3449-3452
Natural-abundance 17O NMR spectra have been measured for twenty one oxiranes. Their chemical shifts covering a 100 ppm range were interpreted in terms of the paramagnetic β- and diamagnetic γ-effects. In addition, through-space orbital interaction between the ethylenic π and the Walsh orbitals of the oxirane ring was suggested by a lowfield shift in norbornadiene -oxide. 相似文献
6.
Sahara R Ichikawa H Mizuseki H Ohno K Kubo H Kawazoe Y 《The Journal of chemical physics》2004,120(19):9297-9301
A Monte Carlo simulation is carried out to study thermodynamic properties of Cu-Au alloys using a face-centered-cubic (fcc) lattice-gas model. To obtain quantitatively accurate results, a Finnis-Sinclair-type potential, which has been widely used for molecular dynamics (MD) simulations, is employed. To overcome some shortcomings of lattice-gas models such as neglecting vibrational entropy, the potential is mapped onto the fcc lattice using the renormalization technique. The renormalized potential gives an improved Cu-Au phase diagram compared to the original MD potential applied directly on the lattice. 相似文献
7.
Air containing particulate material was passed continuously for one month through a low-volume air sampler equipped with a cyclone to exclude particulates greater than 10 μm in diameter. The samples and filters were ashed in a low-temperature plasma and, after addition of In2O3 support, palladium internal standard and graphite buffer, the ashes were analyzed by a.c. are emission spectrometry. Standard samples were prepared from a commercial standard containing 49 elements. The procedure allows the determination of 14 trace metals (Ag, Al, Cr, Cu, Fe, Ga, Mn, Mo, Ni, Pb, Sn, Ti, V, Zn) with relative standard deviations of 1.4–15.1%. The procedure has been applied successfully to monthly determinations of the average atmospheric concentrations of these elements in Kobe City for the past three years. 相似文献
8.
9.
Electron beam treatment of lignite-burning flue gas with high concentrations of sulfur dioxide and water 总被引:5,自引:0,他引:5
Hideki Namba Shoji Hashimoto Okihiro Tokunaga Ryoji Suzuki 《Radiation Physics and Chemistry》1998,53(6):673-681
Experiments were carried out to investigate the removals of SO2 and NOx from simulated lignite-burning flue gas containing SO2 (4800 ppm), NO (320 ppm) and H2O (22%) by electron beam irradiation. Removal efficiencies of SO2 and NOx were achieved to reach 97 and 88% at 70°C, and 74 and 85% at 80°C, respectively, with the dose of 10.3 kGy without NH3 leakage. The higher removal efficiencies of SO2 and NOx were observed in simulated lignite-burning flue gas than in coal-fired flue gas containing 800 ppm of SO2, 225 ppm of NO and 7.5% H2O at the same treatment condition. The higher removal efficiencies were attributed to the higher concentrations of SO2, H2O, and added NH3. Simulation calculations indicated that the higher concentrations of these components enhance the effective radical reactions to oxidize NO to form NO2 with HO2 radical, and to oxidize SO2 to form SO3 with OH radical and O2. The reactions of NOx with N and NH2 radicals to produce N2 and N2O also promote the NOx removal. By-product was determined to be the mixture of (NH4)2SO4 and NH4NO3 containing a small amount of H2SO4. 相似文献
10.
Bound state pion production in40Ca and120Sn nuclei in (p,2p) and (n,d) reactions is investigated. The differential and total cross sections have been obtained. It is shown that the cross sections are determined by the overlap function of the bound states of the nucleon and pion, and as consequence,s-wave part of the pion-nucleus optical potential. The contributions from the nucleons and deuteron distortions are evaluated.The authors would like to express their gratitude to R.A. Eramzhyan, S.N. Gninenko, V.B. Kopeliovich, V.M. Lobashev, B.B. Matveev and E. Oset for very useful and stimulating discussions. 相似文献