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排序方式: 共有511条查询结果,搜索用时 15 毫秒
1.
2.
Shingo Kanehira Soshu Kirihara Yoshinari Miyamoto Kazuaki Sakoda Mitsuo Wada Takeda 《Journal of the American Ceramic Society》2003,86(10):1691-1694
Photonic crystals with a diamond structure of epoxy lattices in which TiO2 -based ceramic particles are dispersed were fabricated by stereolithography. The periodicity of the lattice was designed to reflect electromagnetic waves in the gigahertz range. The volume fraction (β) of the dielectric lattice medium was modified from 14% to 33% by changing the rod diameter of the lattice. The photonic band gap was observed along Γ-L 〈111〉, Γ-X 〈100〉, and Γ-K 〈110〉 directions and the complete photonic band gap was formed at over β= 20%. The width of the forbidden gap increased gradually when the β increased over 14%, and reached 2.4 GHz at β= 33%. These results agreed with the band calculation using the plane wave expansion method. 相似文献
3.
Poly(butylene succinate) and organically modified montmorillonite nanocomposites with there different compositions were prepared via melt blending in a twin‐screw extruder. The structure of the nanocomposites was studied with X‐ray diffraction and transmission electron microscopy, which revealed the formation of intercalated nanocomposites, regardless of the silicate loading. Dynamic mechanical analysis revealed a substantial increase in the storage modulus of the nanocomposites over the entire temperature range investigated. The tensile property measurements showed a relative increase in the stiffness with a simultaneous decrease in the yield strength in comparison with that of neat poly(butylene succinate). The oxygen gas barrier property of neat poly(butylene succinate) improved after nanocomposite preparation with organically modified montmorillonite. The effect of the layered‐silicate loading on the melt‐state linear viscoelastic behavior of the intercalated nanocomposites was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 777–785, 2006 相似文献
4.
Hamid Noori Farhad Mehdipour Kazuaki Murakami Koji Inoue Morteza Saheb Zamani 《The Journal of supercomputing》2008,45(3):313-340
To improve the performance of embedded processors, an effective technique is collapsing critical computation subgraphs as
application-specific instruction set extensions and executing them on custom functional units. The problem with this approach
is the immense cost and the long times required to design a new processor for each application. As a solution to this issue,
we propose an adaptive extensible processor in which custom instructions (CIs) are generated and added after chip-fabrication.
To support this feature, custom functional units are replaced by a reconfigurable matrix of functional units (FUs). A systematic
quantitative approach is used for determining the appropriate structure of the reconfigurable functional unit (RFU). We also
introduce an integrated framework for generating mappable CIs on the RFU. Using this architecture, performance is improved
by up to 1.33, with an average improvement of 1.16, compared to a 4-issue in-order RISC processor. By partitioning the configuration
memory, detecting similar/subset CIs and merging small CIs, the size of the configuration memory is reduced by 40%. 相似文献
5.
A thermodynamic property model with new mixing rules using the Helmholtz free energy is presented for the binary mixture of
methane and hydrogen sulfide based on experimental Pρ Tx data, vapor–liquid equilibrium data, and critical-point properties. The binary mixture of methane and hydrogen sulfide shows
vapor–liquid–liquid equilibria and a divergence of the critical curve. The model represents the existing experimental data
accurately and describes the complicated behavior of the phase equilibria and the critical curve. The uncertainty in density
calculations is estimated to be 2%. The uncertainty in vapor–liquid equilibrium calculations is 0.02 mole fraction in the
liquid phase and 0.03 mole fraction in the vapor phase. The model also represents the critical points with an uncertainty
of 2% in temperature and 3% in pressure. Graphical and statistical comparisons between experimental data and the available
thermodynamic models are discussed 相似文献
6.
Jiyoung Choi Toshio Takayama Hwan-Chul Yu Chan-Moon Chung Kazuaki Kudo 《Polymer》2012,53(6):1328-1338
Nanoporous films were prepared with alicyclic copolyimides (coPIs) having polypropylene glycol (PPG) side chains by way of spontaneous phase separation in the film forming process and the subsequent thermal degradation of PPG moieties. PIs having various content (6.5, 11.9, 26.3, 52.7 wt%) and different length (Mw = 1.2 × 103 and 2.4 × 103) of PPG side chains were examined in order to clarify the relationship between chemical structure and pore characteristics. Nanopores were formed by heating the coPI films at 200 °C for 9 h under slightly reduced pressure. The size and the number of the pores observed by SEM varied depending on the content and molecular weight of PPG moieties. In many cases, the pore size was larger than those of the reported values for related aromatic copolyimide films. The dielectric constant of the nanoporous films ranged from 2.52 to 3.38. 相似文献
7.
Main‐chain smectic liquid crystalline polymer exhibiting unusually high thermal conductivity in an isotropic composite 下载免费PDF全文
Shusuke Yoshihara Masatoshi Tokita Toshiaki Ezaki Mitsuru Nakamura Masashi Sakaguchi Kazuaki Matsumoto Junji Watanabe 《应用聚合物科学杂志》2014,131(6)
The thermal conductivity (TC) of an isotropic composite comprising of a main‐chain smectic liquid crystalline PB‐10 polyester and 50‐μm‐sized roughly spherical magnesium oxide (MgO) particles is investigated. The increase in the composite TC with higher MgO fractions is steeper than that expected by Bruggeman's theory for the TC of a polydomain PB‐10 polyester (0.52 W m?1 K?1). When the filler content is larger than 30 vol %, the composite TC approaches a value that can be explained only if the polyester functions as a matrix with 1.0 W m?1 K?1, which is five times as high as those of isotropic common polymers (0.2 W m?1 K?1). Such an unusually high TC for a polymer matrix is attributed to some polymer lamellae that lie parallel to the particle surface and are stacked toward neighboring particles, thus creating effective heat paths between the particles and a continuous thermal network in a composite. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39896. 相似文献
8.
Shinzi Kato Hideki Kageyama Kazutaka Takagi Kazuaki Mizoguchi Toshiaki Murai 《Advanced Synthesis \u0026amp; Catalysis》1990,332(6):898-910
A series of sodium selenocarboxylates 2 were isolated from the reaction of diacyl selenides with sodium ethanolate and characterized. A convenient preparation of the sodium salts 2 by the direct reaction of acyl chlorides with sodium selenide was also established. The salts are colourless to slightly pale yellow crystals and labile towards moisture. They readily react with alkyl iodides at room temperature to give the corresponding Se-alkyl esters 3 . 相似文献
9.
Saka M Iijima K Nishida M Koma Y Hasegawa N Sato K Kato Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2008,49(3):160-167
The effects of processing and cooking on the levels of pesticide residues in soybean samples were investigated for 14 pesticides in pre-harvest samples. On soaking, the transfer ratios (%, total pesticide residue amount in product/that in soybean) of soaked soybean were greater than 60% for most of the pesticides investigated. The transfer ratio of soymilk ranged from 37% to 92%, and that of tofu ranged from 7% to 63%. The processing factor (Pf, the concentration (mg/kg) of pesticide in product/that in soybean) of tofu ranged from 0.026 to 0.28. These values varied among pesticides. There was a high correlation between the log P(ow) and the transfer ratio of tofu. The test described here should be useful to obtain the transfer ratios of pesticide residues in processing and/or cooking steps. 相似文献
10.
Kazuaki Nakamura Reiko Mizutani Atsushi Sanbe Shin Enosawa Mureo Kasahara Atsuko Nakagawa Yoko Ejiri Norie Murayama Yuki Miyamoto Tomohiro Torii Shinji Kusakawa Junji Yamauchi Motohiro Fukuda Hiroshi Yamazaki Akito Tanoue 《Journal of Bioscience and Bioengineering》2011,111(1):78-84
A micro-space cell culture system was recently developed in which cells such as hepatocytes can be cultured and formed into a multicellular three-dimensional (3D) architecture. In this study, we assessed the performance of HepG2 cells cultured in this micro-space cell culture system in a drug toxicity test, and evaluated the effects of micro-space culture on their hepatocyte-specific functions. The micro-space cell culture facilitated the formation of 3D HepG2 cell architecture. HepG2 cells cultured in a micro-space culture plate exhibited increased albumin secretion and enhanced mRNA expression levels of cytochrome P450 (CYP) enzyme compared to those cultured in a monolayer culture. When the cells were exposed to acetaminophen, a hepatotoxic drug, the damage to the HepG2 cells grown in micro-space culture was greater than the damage to the HepG2 cells grown in monolayer culture. In addition, human primary hepatocytes grown in micro-space culture also exhibited increased albumin secretion, enhanced CYP mRNA expression levels and increased sensitivity to acetaminophen compared to those grown in monolayer culture. These results suggest that this micro-space culture method enhances the hepatocyte-specific functions of hepatocytes, including drug-metabolizing enzyme activities, making hepatocytes grown in the micro-space culture system a useful tool for evaluating drug toxicity in vitro. 相似文献