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排序方式: 共有1353条查询结果,搜索用时 15 毫秒
51.
Haruyuki Murakami Hiroshi Ueda Atsushi Ishiyama Norikiyo Koizumi Kiyoshi Okuno 《Electrical Engineering in Japan》2010,171(3):7-15
In the ITER Engineering Design Activity (EDA), four NB3Sn model coils were developed and successfully tested. However, it was revealed that the critical current of the conductor degraded with the increase of electromagnetic force. One of the explanations of this phenomenon is a strand bending caused by enormous electromagnetic force. The authors therefore developed a simulation code using the distributed circuit model to investigate dependency of the critical current performance on the periodic bending deformation. The simulation results were in good agreement with the experiments. The dependence of the critical current on the periodic transverse load, temperature, periodic load pitch, thickness of Ta barrier which prevents Cu stabilizer from being contaminated by Sn, twist pitch of the strand, and RRR of the bronze matrix was investigated using the developed code. The results showed that the critical current degraded less with decreasing the pitch of the transverse load and increasing the Ta barrier thickness. It suggests that the shorter cabling pitch and the larger bending stiffness prevent the critical current degradation. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(3): 7–15, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20923 相似文献
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Many compounds that taste bitter to humans also inhibit feeding in insects. Caterpillars (e.g., Manduca sexta) detect these compounds with a few bitter-sensitive taste cells. This study examined the role of these taste cells in feeding inhibition. Behavioral studies demonstrated that 3 bitter compounds (caffeine, salicin, and aristolochic acid) all inhibited feeding rapidly in Manduca sena. Electrophysiological studies revealed that each pair of bitter-sensitive taste cell differs in responsiveness to the bitter compounds. Ablation studies indicated that (a) those pairs of bitter-sensitive taste cells that responded vigorously to a particular bitter compound were sufficient to inhibit feeding on diets containing the same compound, but that (b) no pair of bitter-sensitive taste cells was necessary for inhibiting feeding. Thus, the different pairs of bitter-sensitive taste cells appear to make partially redundant contributions to feeding inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
A molecular structure viewer program, MOSBY has been developed for studies that use atomic coordinates to understand the structures of protein molecules. The program is designed to be portable with a comprehensive user interface by our high-throughput graphics library. In addition, it cooperates with extension modules customized for individual research topics and analysis. For example, an electron density module loads and displays electron density maps derived in X-ray crystallographic analysis superimposed to an atomic model. A molecular dynamics module reads a trajectory file of the results of molecular dynamics calculations and animates the structure. These plug-in modules are devised to function without modification to the MOSBY program. For variations of analysis and calculations with atomic coordinates, the portability and extensibility illustrated by MOSBY play an important rule in scientific computational tools with active software development. 相似文献
55.
Honda Y Kitaoka M Sakka K Ohmiya K Hayashi K 《Journal of Bioscience and Bioengineering》2002,93(3):313-317
The kinetic parameters of Cex, a family 10 xylanase from Cellulomonas fimi, were determined at various pH levels using soluble birchwood xylan (BWX) as a natural polymeric substrate along with three other synthetic aryl-beta-D-xylobioside substrates. Using BWX, a high level of substrate inhibition was observed which increased with decreasing pH. In contrast, typical Michaelis-Menten-type profiles were obtained using the three aryl-beta-D-xylobiosides as substrates. The k(cat) values determined using o-nitrophenyl-beta-D-xylobioside did not change as the pH increased, whereas the k(cat) values obtained with BWX, phenyl-beta-D-xylobioside and p-nitrophenyl-beta-D-xylobioside decreased, suggesting that the presence of an ortho nitro group affects the activity displayed by Cex. These differences were not observed with XynB from Clostridium stercorarium F9, a member of the same family of xylanases as Cex. These results indicate that a careful evaluation is required when employing substituted aryl-beta-D-xylobiosides in the characterization of xylanases. 相似文献
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57.
Keisuke Hachisuka Teruhito Takeda Yusuke Terauchi Ken Sasaki Hiroshi Hosaka Kiyoshi Itao 《Microsystem Technologies》2005,11(8-10):1020-1027
Intra-body communication is a wireless means of exchanging information within a personal area network (PAN) between wearable electronic sensors and devices. The feasibility of intra-body communication is confirmed through several experiments on signal propagation within the human body, and a human phantom is designed and used to obtain reproducible results over repeated experiments. Based on the results of these experiments, a prototype transmission system is constructed using aluminum electrodes powered by 3 V DC and operating in the 10.7 MHz frequency modulation (FM) band. This prototype is demonstrated to be capable of transmitting analog signals through the human subjects in the presence of external noise. Digital data transmission at 9600 bps is also achieved using newly fabricated 10.7 MHz frequency shift keying (FSK) transmitter and receiver devices. The carrier frequency of 10.7 MHz is the intermediate frequency of FM radio receivers, meaning that the proposed system can make use of a wide selection of inexpensive, commercial radio frequency devices. 相似文献
58.
Makoto Ishii Kenji Saito Tomokazu Shiga Kiyoshi Igarashi Shigeo Mikoshiba Jooyul Lee Kyoung Ho Kang Heehwan Kim Changbae Park 《Journal of the Society for Information Display》2002,10(1):5-10
A hybrid AWD/AND drive technique has been developed in which an Address‐While‐Display (AWD) scheme is combined with an AND logic characteristic that gas discharges demonstrate. The AWD technique enables AC‐PDPs to be driven at high luminance, while the AND logic reduces the number of scan drivers by an order of magnitude. A detailed analysis of the addressing operation has been made. The hybrid drive utilizes the AND logic in two ways: (1) a combination of two voltage pulses and (2) a combination of a voltage pulse and discharge‐priming particles. It was found that the addressing operation requires the establishment of a discharge between the scan and data electrodes, and also between the scan and display electrodes. 相似文献
59.
Ryosuke Ueyama Masahiro Harada Tamotu Ueyama Takashi Yamamoto Tadashi Shiosaki Kiyoshi Kuribayashi Kunihito Koumoto Won Son Seo 《Journal of Materials Science: Materials in Electronics》2000,11(2):139-143
Ultrafine BaTiO3 particles were prepared by a micro-emulsion charring (MEC) method. The MEC method consisted of two steps. The first step is the preparation of a water/oil micro-emulsion with BaTiO3 elements, and the second is a low temperature firing process in N2 atmosphere, which includes charring of oil in an emulsion and powdering BaTiO3 particles with the char. The char formed around BaTiO3 particles prevents an agglomeration of BaTiO3 particles during firing. In the present experiment, the W/O ratio and the amount of emulsifier greatly influenced the size of droplets of the emulsion. The charring temperature was another important experimental factor in order to obtain the desired BaTiO3 particles. The finally obtained BaTiO3 charring powders were monodispersed spherical particles and the particle size was 0.1 m to 0.5 m. 相似文献
60.
Processing and Thermal Conductivity of Sintered Reaction-Bonded Silicon Nitride. I: Effect of Si Powder Characteristics 总被引:2,自引:0,他引:2
Xinwen Zhu You Zhou Kiyoshi Hirao Zoltán Lené 《Journal of the American Ceramic Society》2006,89(11):3331-3339
This paper will present sintered reaction-bonded silicon nitride (SRBSN) material with a high thermal conductivity of 121 W·(m·K)−1 , which has been successfully prepared from a coarse Si powder with lower levels of oxygen and aluminum impurities, using a mixture of Y2 O3 and MgSiN2 as sintering additives, by nitriding at 1400°C for 8 h and subsequent post-sintering at 1900°C for 12 h at a nitrogen pressure of 1 MPa N2 . This thermal conductivity value is higher than that of the materials prepared from high-purity α-Si3 N4 powder (UBE SN-E10) with the same additive composition under the same sintering conditions. In order to study the effects of Si powder characteristics on the processing, microstructure, and thermal conductivity of SRBSN, the other type of fine powder with higher native oxygen and metallic impurity (typically Al and Fe) contents was also used. The effects of Si particle size, native oxygen, and metallic impurities on the nitriding process, post-sintering process, and thermal conductivity of the resultant SRBSN materials were discussed in detail. This work demonstrates that the improvement in thermal conductivity of SRBSN could be achieved by using higher purity coarse Si powder with lower levels of oxygen and aluminum impurities. In addition, this work also shows that the nitriding temperature has no significant effect on the microstructure and thermal conductivity of SRBSN during post-sintering, although it does affect the characteristics of RBSN formed during nitridation. 相似文献