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61.
Takanori Sone Hirokazu Akagi Hisao Watarai 《Journal of the American Ceramic Society》1991,74(12):3151-3153
Pore behavior as influenced by migration of an abnormal grain boundary was studied. The pore behavior during the discontinuous growth of hot-pressed spinel (MgAl2 O4 ) — whether the pore can move attached to the grain boundary — is particularly governed by the pore size and the matrix grain size. These phenomena can be understood from the interaction between the pore and the abnormal grain boundary. 相似文献
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CYP3A7 is a form of cytochrome P450, which is expressed specifically in human fetal livers. NPVHF1, a recombinant baculovirus containing the entire coding region of CYP3A7, was constructed and infected to Spodoptera frugiperda (Sf9) cells. Upon infection with NPVHF1, the Sf9 cells expressed the CYP3A7 to the maximum content of 0.2 nmol per mg of whole cell lysates 72 hours after infection. A 5.5-fold expression level (1.1 nmol per mg of whole cell lysates) was attainable when cultured in the presence of externally added hemin. A catalytic activity of the CYP3A7 expressed in the Sf9 cells was confirmed by the umu gene expression mutation assay, in which aflatoxin B1 was activated to a mutagen by the expressed CYP3A7 in the presence of NADPH-cytochrome P450 reductase and cytochrome b5. From these results, it is concluded that the baculovirus expression system enables the high-level expression of CYP3A7 and will be a very useful tool for the characterization of CYP3A7. 相似文献
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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
67.
This work reports the results of laboratory drilling tests conducted in order to measure improvements due to design and cutter modifications on PDC bits intended for use in geothermal well drilling. These tests, using 142.88 mm-dia. PDC full face bits, concentrated on improvements in bit life and cost performance. The tests were performed using granite drilling samples and a laboratory drilling machine at atmospheric conditions. The results from changes in bit and cutter shape are reported in the work. 相似文献
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Hirokazu Yoshizawa Gabor C. Temes 《IEEE transactions on circuits and systems. I, Regular papers》2007,54(1):193-199
This paper describes high-precision switched-capacitor (SC) track-and-hold amplifier (THA) stages. They use a novel continuous-time correlated double sampling (CDS) scheme to desensitize the operation to amplifier imperfections. Unlike earlier predictive-CDS amplifiers, the circuits do not need a sampled-and-held input signal for their operation. During the tracking period, an auxiliary continuous-time signal path is established, which predicts the output voltage during the holding period. This allows accurate operation even for low amplifier gains and large offsets over a wide input frequency range. Extensive simulations were performed to compare the performance of the proposed THAs with earlier circuits utilizing CDS. The results verify that their operation is far more robust than that of any previously described SC amplifiers 相似文献
70.
Tsutomu Nagata Yoichi Nagata Hirokazu Koshimitsu 《Computers & Industrial Engineering》1993,24(4):561-569
The position of a production management system in a computer-integrated manufacturing (CIM) system is to serve as the nucleus of the plant CIM system that connects the plant production to other departments such as marketing, research and development, and distribution departments. A production management system that integrates the flow of goods with information in a plant, and thus manages production in it, was developed as the first step toward application of CIM to a powder plant. The method of building a distributed system is one way to build a CIM system. This method creates a system in the required function units, which are connected by a network to expand the system function. It offers advantages in extensibility, flexibility, and rapid implementation. 相似文献