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991.
J.-I. Yamaki S.-I. Tobishima Y. Sakurai K.-I. Saito K. Hayashi 《Journal of Applied Electrochemistry》1998,28(2):135-140
Rechargeable cells with lithium metal anodes have a very large theoretical energy density and are a promising cell system. However, rechargeable lithium metal cells are not yet currently commercially available. One of the biggest problems with the cells is the poor safety aspect resulting from the high chemical reactivity of lithium. We have been studying a cell system consisting of an amorphous (a-)V2O5P2O5 (95:5 in molar ratio) cathode, a lithium (Li) metal anode and an organic electrolyte in fabricating an AA-size prototype. In this paper, we report recent progress on our rechargeable lithium metal cell focusing on its safety. 相似文献
992.
Jamil Toyir Masahiro Saito Isamu Yamauchi Shengcheng Luo Jingang Wu Isao Takahara Masami Takeuchi 《Catalysis Today》1998,45(1-4):245-250
Catalytic hydrogenation of CO2 into methanol has been investigated over Raney Cu-based catalysts. The Raney catalysts leached in NaOH/ZnO solutions showed high activities and selectivities for methanol synthesis. The deposition of Zn on the surface of Cu particles increased the surface area and the specific activity of Raney Cu–M. Raney Cu–Zr developed was significantly more active than a commercial catalyst. 相似文献
993.
Efficient and Handy Texture Mapping on 3D Surfaces 总被引:2,自引:0,他引:2
There has been a rapid technical progress in three-dimensional (3D) computer graphics. But gathering surface and texture data is yet a laborious task. This paper addresses the problem of mapping photographic images on the surface of a 3D object whose geometric data are already known. We propose an efficient and handy method for acquiring textures and mapping them precisely on the surface, employing a digital camera alone. We describe an algorithm for selecting a minimal number of camera positions that can cover the entire surface of a given object and also an algorithm to determine camera's position and direction for each photograph taken so as to paste it to the corresponding surfaces precisely. We obtained a matching accuracy within a pixel on a surface through three experimental examples, by which the practicability of our method is demonstrated. 相似文献
994.
Hiroyuki Okamura Ryuichi Ohtani Kiyoshi Saito Kazushige Kimura Ryuichi Ishii Kazunari Fujiyama Shigetada Hongo Takashi Iseki Hiroshi Uchida 《Nuclear Engineering and Design》1999,193(3):243
In order to develop life assessment techniques for aged components made of modified 9Cr–1Mo steel, specimens were artificially deteriorated by aging, creep and fatigue tests at elevated temperatures, and associated changes in the microstructure and mechanical properties were examined. It was observed that aging resulted in formation of Laves phase causing a decrease in toughness. The creep damage in base metal could be correlated with decrease in hardness, while creep damage in weldments could be correlated with the area fraction and density of creep voids. Creep rupture in weldments occurred in the fine-grained heat affected zone by the formation and growth of creep voids. The fatigue damage in base metal correlated to the maximum length of a crack among micro-cracks initiated during fatigue cycles. 相似文献
995.
Tongyao Zhang Hanwen Wang Xiuxin Xia Ning Yan Xuanzhe Sha Jinqiang Huang Kenji Watanabe Takashi Taniguchi Mengjian Zhu Lei Wang Jiantou Gao Xilong Liang Chengbing Qin Liantuan Xiao Dongming Sun Jing Zhang Zheng Han Xiaoxi Li 《光:科学与应用(英文版)》2022,(3):365-374
The nano-opto-electro-mechanical systems (NOEMS) are a class of hybrid solid devices that hold promises in both classical and quantum manipulations of the inter... 相似文献
996.
Masahiko Satoh Tamie Suzuki Tetsuhito Sakurai Sumika Toyama Yayoi Kamata Shinya Kondo Yasushi Suga Mitsutoshi Tominaga Kenji Takamori 《International journal of molecular sciences》2021,22(19)
Neuronal morphological changes in the epidermis are considered to be one of causes of abnormal skin sensations in dry skin-based skin diseases. The present study aimed to develop an in vitro model optimised for human skin to test the external factors that lead to its exacerbation. Human-induced pluripotent stem cell-derived sensory neurons (hiPSC-SNs) were used as a model of human sensory neurons. The effects of chemical substances on these neurons were evaluated by observing the elongation of nerve fibers, incidence of blebs (bead-like swellings), and the expression of nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2). The nerve fiber length increased upon exposure to two common cosmetic preservatives—methylparaben and phenoxyethanol—but not to benzo[a]pyrene, an air pollutant at the estimated concentrations in the epidermis. Furthermore, the incidence of blebs increased upon exposure to benzo[a]pyrene. However, there was a decrease in the expression of NMNAT2 in nerve fibers, suggesting degenerative changes. No such degeneration was found after methylparaben or phenoxyethanol at the estimated concentrations in the epidermis. These findings suggest that methylparaben and phenoxyethanol promote nerve elongation in hiPSC-SNs, whereas benzo[a]pyrene induces nerve degeneration. Such alterations may be at least partly involved in the onset and progression of sensitive skin. 相似文献
997.
Katsumi Tsuchiya Masanobu Koshihata Tahei Tomida Takayuki Saito 《Korean Journal of Chemical Engineering》1999,16(5):635-639
The dynamic process of gas absorption from a CO2 bubble into a liquid is examined in the presence of satellite bubbles. The bubble under consideration is held stationary,
except its jittering, by the liquid flowing downward. The mass transfer rate is determined by monitoring the rate of reduction
in the equivalent bubble diameter during the initial absorption process. It is found that the interaction with the satellite
bubbles generally hampers the dissolution of the primary bubble. The extent of reduction in the dissolution rate increases
with the net contacting time during the interaction. When the secondary bubbles interact with the primary bubble mainly outside
of its wake, however, the dissolution tends to be enhanced due to induced turbulence in the surrounding liquid flow. A simple
theoretical model is developed to simulate the observed results as well as the basic features prevailing in a recently proposed
scheme, called the GLAD system, for shallow injection of CO2 gas into seawater. 相似文献
998.
Satoshi Kaneco Kenji Iiba Nobu-hide Hiei Kiyohisa Ohta Takayuki Mizuno Tohru Suzuki 《Electrochimica acta》1999,44(26):4701
The electrochemical reduction of CO2 with a Cu electrode in CsOH/methanol-based electrolyte was investigated. The main products from CO2 were methane, ethylene, ethane, carbon monoxide and formic acid. A maximum Faradaic efficiency of ethylene was 32.3% at −3.5 V vs. Ag/AgCl saturated KCl. The best methane formation efficiency was 8.3% at −4.0 V. The ethylene/methane current efficiency ratio was in the range 2.9–7.9. In the CsOH/methanol, the efficiency of hydrogen formation, being a competitive reaction against CO2 reduction, was depressed to below 23%. 相似文献
999.
Haitao Li Hidenori Yahiro Kenji Komaguchi Masaru Shiotani Einar Sagstuen Anders Lund 《Microporous and mesoporous materials》1999,30(2-3):275-281
Electron spin resonance (ESR) spectroscopy was used to study the effect of zeolite structure on the motional dynamics of NO2 adsorbed on the zeolites. The temperature-dependent ESR spectral line shapes were quantitatively analyzed using the slow-motion ESR theory. It was observed that the motional dynamics of NO2 is strongly dependent on the structure of the zeolite (Beta-type, ZSM-5, mordenite, L-type and ferrierite zeolites). The following important observations were made. (1) In zeolites with similar channel structures, the diffusion rate of NO2 is proportional to the channel size, and the order of the diffusion rates is Beta-type>ZSM-5>ferrierite and L-type>mordenite. (2) The diffusion of NO2 is faster in the zeolites with multi-dimensional channels (Beta-type, ZSM-5 and ferrierite) than that in those with uni-dimensional channels (L-type and mordenite). 相似文献
1000.
Saito Kouhei; Kikuchi Takeshi; Yoshida Michiteru 《Protein engineering, design & selection : PEDS》1999,12(3):235-242
The DNA binding mechanism of box B in HMG1, a member of thesequence non-specific DNA binding HMG1/2-box family of proteins,has been examined by both mutation analyses and molecular modelingtechniques. Substitution of the residue 102F, which is characteristicallyexposed to solvent, with a small hydrophobic amino acid affectedits DNA binding activity. However, no additional effect wasobserved by the further mutation of flanking 101F. Moleculardynamics simulation and modeling studies revealed that 102Fintercalates into DNA base-pairs, being supported by the flanking101F. The mutants with a small hydrophobic residue at position102 tolerated the substitution for 101F because the side chainat position 102 is too short to intercalate. Thus the intercalationof 102F and the positive effect of the flanking 101F residueare important for the sequence non-specific DNA binding of theHMG1/2-box. The conserved basic residues of 95K, 96R and 109Rwere also examined for their roles in DNA binding. These residuesinteracted with DNA mainly by electrostatic interaction andmaintained the location of the box on the DNA, which prescribedthe intercalation of 102F. The DNA intercalation by HMG1 consistsof an ingenious mechanism which brings DNA conformational changesnecessary for biological functions. 相似文献