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排序方式: 共有771条查询结果,搜索用时 31 毫秒
41.
Tatsumi Ishihara Kuninobu Shimose Takanari Kudo Hiroyasu Nishiguchi Taner Akbay Yusaku Takita 《Journal of the American Ceramic Society》2000,83(8):1921-1927
A yttria-stabilized zirconia (YSZ) thin film on an La0.8 Sr0.2 MnO3 porous cathode substrate was prepared, using electrophoretic deposition (EPD) to fabricate a solid oxide fuel cell (SOFC). The electrical conductivity of an La0.8 Sr0.2 MnO3 substrate is satisfactorily high at room temperature; therefore, YSZ powder could be deposited electrophoretically onto an La0.8 Sr0.2 MnO3 substrate without any extra surface treatment, such as a metal coating. Successive repetition of EPD and sintering was required to obtain a film without gas leakage, because of the thermal expansion coefficient mismatch between the YSZ and the La0.8 Sr0.2 MnO3 substrate. On the other hand, the electromotive force of the oxygen concentration in the cell that used YSZ film prepared via EPD increased and attained the theoretical value when the number of deposition and calcination cycles was increased. Six or more successive repetitions were required to obtain a YSZ film without gas leakage. A planar-type SOFC was fabricated, using nickel as the anode and YSZ film (∼10 μm thick) that had been deposited onto the La0.8 Sr0.2 MnO3 substrate as the electrolyte and cathode. The cell exhibited an open circuit voltage of 1.0 V and a maximum power density of 1.5 W/cm2 . Thus, the EPD method could be used as a colloidal process to prepare YSZ thin-film electrolytes for SOFCs. 相似文献
42.
A hybrid adsorption heat pump water heater has been studied for domestic use. It is a water heater with dual heat sources, and it combines the performances of adsorption heat pumps and conventional gas boilers. Moreover, functional adsorbent material‐zeolite (FAM‐Z02, Mitsubishi Chemicals) and water are a new adsorption pair for adsorption heat pumps. This article describes the operation, design, and performance analysis of one such water‐heating device. The experimental results showed that the hybrid water heater in the whole year has a stable COP even at low ambient temperature. The hybrid water heater can thus achieve high energy efficiency. 相似文献
43.
Mutational analysis of structure--activity relationships in human tumor necrosis factor-alpha 总被引:1,自引:0,他引:1
Yamagishi Jun-ichi; Kawashima Hitoshi; Matsuo Noriyuki; Ohue Mayumi; Yamayoshi Michiko; Fukui Toshikazu; Kotani Hirotada; Furuta Ryuji; Nakano Katsuji; Yamada Masaaki 《Protein engineering, design & selection : PEDS》1990,3(8):713-719
To determine the region of human tumor necrosis factor-alpha(TNF-), essential for cytotoxic activity against mouse L-M cells,single amino-acid-substituted TNF- mutant proteins (muteins)were produced in Escherichia coli by protein engineering techniques.An expression plasmid for TNF- was mutagenized by passage throughan E.coli mutD5 mutator strain and by oligonucleotide-directedmutagenesis. Approximately 100 single amino-acid-substitutedTNF- muteins were produced and assayed for cytotoxic activity.The cytotoxic activities of purified TNF- muteins, e.g. TNF-31T,-32Y, -82D, -85H, -115L, -141Y, -144K and -146E, were < 1%of that of parent TNF-. These results indicate that the integrityof at least four distinct regions of the TNF- molecule is requiredfor full biological activity. These regions are designated asfollows: region I, from position 30 to 32; region II, from position82 to 89; region III, from position 115 to 117; region FV, fromposition 141 to 146. In addition, TNF-141Y could not completelycompete with parent TNF- for binding to the receptor. This demonstratesthat region IV, and at least aspartk acid at position 141, mustbe involved in the TNF receptor binding site. 相似文献
44.
Yusaku Takita Jun-ichi Moriyama Hiroyasu Nishiguchi Tatsumi Ishihara Fusakazu Hayano Tetsuo Nakajo 《Catalysis Today》2004,88(3-4):103-109
Activity for hydrolysis of CCl2F2 (CFC12) on various metal sulfate was investigated. Zr(SO4)2 was found to be the most active while FeSO4, Cr2(SO4)3, Al2(SO4)3, La2(SO4)3 and Ce2(SO4)3 had intermediate activity. MnSO4, CoSO4, and MgSO4 showed low activity and SrSO4, CaSO4, and BaSO4 had even less activity. The major carbon containing product was CO2 and small amount of CClF3 and CO were formed over several sulfates. The crystal structure of the sulfates was stable during decomposition of CCl2F2, and the conversion reached a steady state after initial decrease at 275 °C over Zr(SO4)2 catalyst. The concentration of surface hydroxyl was larger than that over AlPO4-based catalysts and a reaction mechanism similar to that over AlPO4-based catalysts was proposed. 相似文献
45.
Noriaki Ikenaga Yoichi Kishi Zenjiro Yajima Noriyuki Sakudo Shizuka Nakano Hisato Ogiso 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(8-9):1509-1513
TiNi alloy samples implanted with various fluences of 3 MeV Cu2+ ions were characterized by transmission electron microscope (TEM) and X-ray diffractometer. Cross-sectional TEM images of the samples showed that amorphous region was seen at the fluence of 1014 ions cm?2 in case of ion implantation at 300 K of the substrate temperature, but in case of ion implantation at 100 K it did not appear even at 1015 ions cm?2. These results were also confirmed by X-ray diffraction profiles of the same samples. Consequently, the extent of microstructure change of TiNi alloy by ion implantation was different depending on the substrate temperature. 相似文献
46.
47.
Tuan Duong Nguyen Noriyuki Takahashi Isao Yamada 《Multidimensional Systems and Signal Processing》2013,24(3):457-483
The contribution of this paper is three-fold: first, we propose a novel scheme for generalized minor subspace extraction by extending an idea of dimension reduction technique. The key of this scheme is the reduction of the problem for extracting the ith (i ≥ 2) minor generalized eigenvector of the original matrix pencil to that for extracting the first minor generalized eigenvector of a matrix pencil of lower dimensionality. The proposed scheme can employ any algorithm capable of estimating the first minor generalized eigenvector. Second, we propose a pair of such iterative algorithms and analyze their convergence properties in the general case where the generalized eigenvalues are not necessarily distinct. Third, by using these algorithms inductively, we present adaptive implementations of the proposed scheme for estimating an orthonormal basis of the generalized minor subspace. Numerical examples show that the proposed adaptive subspace extraction algorithms have better numerical stability than conventional algorithms. 相似文献
48.
Two-crack propagation paths in a ceramic/metal functionally graded material plate (FGP) under one-cycle temperature change of heating and cooling are considered. When the FGP is subjected to thermal shock, a single crack or multiple cracks often initiate on the ceramic surface during the cooling process and propagate in the FGP. Crack paths are influenced by the heating temperature conditions, a compositional profile of the FGP, the fracture toughness, interaction among multiple cracks, and so on. Transient thermal stresses are treated as a linear quasi-static thermoelastic problem for a plane-strain state. The crack paths are treated under fracture mechanics using the finite-element method. The effects of heating temperature conditions, a compositional profile of the FGP, the fracture toughness, and a crack space on the crack propagation pattern are discussed and are shown in figures. 相似文献
49.
Dusida Tirawat Akiko Meno Hiroshi Fujiwara Keizo Higo Seiji Noma Noriyuki Igura Mitsuya Shimoda 《Innovative Food Science and Emerging Technologies》2010,11(3):458-463
We developed a novel rapid hygrothermal pasteurization (RHP) method using saturated water vapor with a dew point of 100 °C. In the present study, the effects of RHP on microbiological quality and quality attributes such as color changes, firmness and ascorbic acid content on many fresh-cut fruits and vegetables (cabbage, cucumber, carrot, cherry tomato, bell pepper, strawberry, pineapple and melon) were investigated. The RHP was performed within a second by free-falling samples through a cylindrical processing chamber filled with steam. The RHP resulted in a 0.7–2.0 log order reduction in the numbers of naturally inoculated mesophilic bacteria. Furthermore, the RHP induced no significant changes in color and firmness of samples, except on the leafy vegetable, cabbage. Ascorbic acid was also retained approximately 80% and above. These results indicate that the RHP is a clean and effective method for decontaminating mesophilic bacteria on fresh fruits and vegetables with minimal changes in quality.Industrial relevanceIn fresh-cut industry, an effective and risk-free decontamination technology is required for use in place of a conventional method, washing by chlorine that can produce carcinogenic chlorinated by-products. In this study, the rapid hygrothermal pasteurization (RHP) method using saturated water vapor was invented and their ability for applying minimal processing was evaluated. The results showed that RHP, without using chemicals, can reduce microorganism load and preserve quality attributes in many kinds of fresh-cut fruits and vegetables. Therefore, RHP could be used as a novel method, which can be generally applicable to fresh-cut fruits and vegetables in the food industry. 相似文献
50.
Presently, it has become an urgent and important concern worldwide to reduce the volume of waste and rationally use the waste for electric power generation. Sludge is a dominant part in the family of wastes. Drying of sludge, not only for volume reduction but also for further utilization, is becoming an essential and integral process. On the other hand, as the requirement of new materials production, for example, fine particles of micron or sub-micron scale for advanced materials, some new drying technologies and techniques have emerged. The market-pull may be the direct and active impetus to drying research and development (R&D). In this paper, drying technologies for sludges, fine particles, coatings as well as advanced dewatering are discussed to reflect the “hot” points of drying and dewatering R&D in Japan. And some novel dryers are also presented. 相似文献