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排序方式: 共有360条查询结果,搜索用时 15 毫秒
31.
Daisuke Saio Toru Amaya Toshikazu Hirao 《Advanced Synthesis \u0026amp; Catalysis》2010,352(13):2177-2182
The hybrid consisting of gold nanoparticles and poly(2‐methoxyaniline‐5‐sulfonic acid), which works as a redox mediator for transferring protons and electrons, catalyzed the oxidation reaction of various alcohols in water under molecular oxygen. 相似文献
32.
Daisuke Kosemura Maki Hattori Tetsuya Yoshida Toshikazu Mizukoshi Atsushi Ogura 《Journal of Electronic Materials》2010,39(6):694-699
Defects and stress gradually accumulate throughout various Si large-scale integration fabrication processes. It is essential
to monitor defects and stress carefully to suppress their unintentional introduction. In this study, we measured the stress
and crystal quality in shallow trench isolation (STI) samples by ultraviolet (UV)-Raman spectroscopy with an extremely high-resolution
wavenumber to evaluate the effect of post-annealing on the recovery of Si crystals. The variations of crystal quality in 200-mm
wafers with STI structures gradually decreased after post-annealing for 4 h, 6 h, and 8 h; however, there was no substantial
difference in the values of full-width at half-maximum of the Raman spectra. Precise measurements of variations of stress
and crystal quality were successfully performed by UV-Raman spectroscopy with a high-resolution wavenumber, which enabled
us to evaluate the STI process accurately. 相似文献
33.
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
34.
Masanori Nishino Yusuke Takemori Satoshi Matsuoka Masaki Kanai Takahiro Nishimoto Masahito Ueda Kyoichi Komori 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(3):358-364
A micro gas chromatography (µGC) instrument applying a high performance chip column fabricated on a silicon wafer was developed. Experimental results of the chip column and protyping of a µGC instrument are described. Approximately 35 000 theoretical plates were generated with the chip column coated liquid phase (5% phenyl-/95% dimethyl-polysiloxane). The theoretical plates of the chip column were close to those of the capillary column. Experimental minimum height equivalent to a theoretical plate (HETP, Hmin) of the chip column was 1.2 times higher than the calculated Hmin. A prototype µGC applying the chip column was developed. The µGC generated approximately 35 000 theoretical plates, similar to the theoretical plates obtained by a commercial GC instrument. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
35.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
36.
The effect of aluminium on the polymerization of silicic acid was studied at pH 7, 8 and 9 in the aluminium concentration range of 0–26 ppm (Al) by spectrophotometry, gel chromatography and 27Al NMR. Retarding and accelerating effects of aluminium on the growth of polysilicic acid particles and on the reaction between monosilicic acid and polysilicic acid were observed by changing the pH. It is suggested that the accelerating effect on the reaction between polysilicic acid particles is due to the formation of aluminium hydroxide on the surface of polysilicic acid. The rate of decrease in the monosilicic acid concentration in the presence of aluminium was faster than that in the absence of aluminium at pH 9, because monosilicic acid could be adsorbed rapidly on the aluminium hydroxide. From the results it was presumed that the formation of aluminium hydroxide on the solid surface may accelerate the deposition of silicic acid from geothermal water. 相似文献
37.
The fracture toughness characterization of four impact-modified polymers based on the J-integral concept was studied. We have discovered that the use of the “crack blunting line” concept needs revision. Direct measurements of the crack growth can be made (as opposed to indirect readings from the fracture surface) that test the applicability of the crack blunting concept. Our results indicate that for rubber-toughened polymers the use of the blunting line fails to specify properly the critical J-integral value for crack initiation. 相似文献
38.
Shin’ichi Konno Shigeo Kazama Maki Hiraoka Hirokazu Sakamoto Kenji Mizoguchi Hiromi Taniguchi Toshikazu Nakamura Kou Furukawa 《Journal of Low Temperature Physics》2006,142(3-4):621-624
β′-(BEDT-TTF)(TCNQ) is a compound of BEDT-TTF (=ET) and TCNQ molecules aligned orthogonally with each other, forming two-dimensional
sheets and one-dimensional columns of 1/4-filled π band, respectively. It is known that the metal-insulator transition occurs
at 330 K at ambient pressure. We have measured the electronic spin susceptibility by means of the EPR-NMR method at 50 MHz,
and the angular dependence of g-factor and line width of EPR both at Q (34 GHz) and W (94 GHz) band. We successfully confirmed
that the antiferromagnetic transition occurs in ET sheets and TCNQ columns, independently. 相似文献
39.
Toshikazu Hori Yoshiyuki Mohri Yuji Kohgo Kenichi Matsushima 《Soils and Foundations》2011,51(1):53-66
Failures of earth dam embankments and river dikes, which are constructed of sandy soils with low dry densities, have been observed to occur during rising of water levels. In this paper, a large-scale physical model test was conducted in order to investigate the behavior of a small dam embankment as water levels rose. The test results were simulated by use of a consolidation analysis method coupled with an elastoplastic model for unsaturated soils. All parameters used in the simulation were obtained from element tests; oedometer, triaxial compression, soil water retention, and permeability tests. First, in order to verify the parameters identified, direct shear tests were simulated using the consolidation analysis method; results of the simulation and the tests were consistent. From the embankment model test it was found that the crest of the embankment moved upstream at the first stage of impounding and then moved back. After a seepage surface appeared on the downstream slope, tension cracks occurred on the downstream slope, and sliding occurred through the crack and the downstream toe. The results of the simulation were consistent with those of the model test. This consolidation analysis method could be used to simulate the complex deformations induced by saturation collapse and shear strains and even failure behavior. Old embankments constructed with loose densities might have histories in which cracks occurred on the downstream slopes when the reservoir water level rose, and their stabilities might have decreased. 相似文献
40.
Lihe Qian Hiroyuki Toda Toshikazu Akahori Mitsuo Niinomi Toshiro Kobayashi Seishi Nishido 《Metallurgical and Materials Transactions A》2005,36(11):2979-2992
Hypoeutectic Al-Si alloys consist of primary α-Al and Al-Si eutectic phases and show typical elasticplastic fracture. To understand their fracture behavior, fracture processes
were simulated using an elastic-plastic finite-element method. The validity of the J-integral-based criterion was verified and applied to the simulations. A complicated model was used to simulate the fracture
in an idealized dendritic microstructure, and four simplified models were intended to more clearly understand the interaction
between a crack and individual α phases. Results show that the crack is attracted to the soft α phase when passing by the α phase, whereas it is repelled when the α phase is close in front of or behind the crack tip. The presence of α phase close in front of or behind the crack tip leads to an amplification of the driving force. However, the α phase beside the tip reduces the driving force. Furthermore, the fracture behavior is mainly affected by the adjacent α phase on one side around the crack tip, while the remote α phase on the opposite side has an offsetting effect. The local stress-strain fields were examined to analyze the simulated
behavior. The simulated crack-growth path in the dendritic model was compared and verified with the experimentally observed
path. 相似文献