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81.
Satoshi Murakami Kazuhiro Satou Taturo Kijima Masataka Watanabe Taeko Izumi 《European Journal of Lipid Science and Technology》2011,113(4):450-458
The enantiopure of (R)‐(?) MαNPA was allowed to react with racemic 18‐(tert‐butyldimethylsilyloxy)‐5‐octadecayne‐7‐ol which was derived from dodecane‐1,12‐diol, yielding diastereomeric esters mixture. These racemic esters were easily separated by HPLC on silica‐gel. The absolute configurations of the first‐eluted diastereomeric esters from the separated esters were determined using 1H NMR anisotropy method. Analysis on 1H NMR spectra and HPLC elution time of the synthesized esters and those of MαNP ester derived from natural methyl‐12‐hydroxystealate showed that the absolute configuration of natural 12‐hydroxystearic acid was R form, and the enantiomeric excess was over 99%. 相似文献
82.
Satoshi Kaneco Nobu-hide HieiYue Xing Hideyuki KatsumataHisanori Ohnishi Tohru SuzukiKiyohisa Ohta 《Electrochimica acta》2002,48(1):51-55
The electrochemical reduction of CO2 on a Cu electrode was investigated in aqueous NaHCO3 solution, at low temperature. A divided H-type cell was employed, the catholyte was 0.65 mol dm−3 NaHCO3 aqueous solution and the anolyte was 1.1 mol dm−3 KHCO3 aqueous solution. The temperature during the electrolysis of CO2 was decreased stepwise to 271 K. Methane and formic acid were obtained as the main products. The maximum Faradaic efficiency of methane was 46% at −2.0 V and 271 K. The efficiency of hydrogen formation, a competing reaction of CO2 reduction, was significantly depressed with decreasing temperature. Based on the results of this work, the proposed electrochemical method appears to be a viable means for removing CO2 from the atmosphere and converting it into more valuable chemicals. The synthesis of methane by the electrochemical method might be of practical interest for fuel production and the storage of solar energy. 相似文献
83.
A solid oxide fuel cell constructed from Ni-SDC anode and LSGM electrolyte was applied to the partial oxidation of methane to syngas (CO+H2) at 700-800 °C with the merits of co-generation of electricity and controllable O2 supply. It was found that the co-generated syngas at H2/CO ratio of 1.4-2.0 varied with applied current densities, CH4 flow rates and operating temperatures. The cell voltage at 100 mA cm−2 and 800 °C was 0.90 V, i.e. about 90 mW cm−2 power density could be obtained. The cell operating at 50 mA cm−2 for 24 h almost showed no degradation of the cell performance. The observed carbon deposition seemed mainly taking place by CH4 cracking reaction. 相似文献
84.
Shuichi Nojima Masashi ToeiShigeo Hara Satoshi TanimotoShintaro Sasaki 《Polymer》2002,43(14):4087-4090
We have investigated the size dependence of crystallization within spherical microdomains formed in various poly(ε-caprolactone)-block-polybutadiene diblock copolymers (PCL-b-PB). The crystallinity (χ) and melting temperature (Tm) of the PCL block are considerably lower than those of PCL homopolymer, and χ decreases steadily and Tm decreases only slightly with decreasing radius of PCL spheres (R) for a series of PCL-b-PB with a same molecular weight (Mn). When PCL-b-PB is compared with the similar R but different Mn, χ is significantly different, suggesting that the sphere size is not the unique factor to control crystallization within spherical microdomains. 相似文献
85.
Takaaki Tsurumi Young-Bae Kil Kouhei Nagatoh Hirofumi Kakemoto Satoshi Wada Sadayuki Takahashi 《Journal of the American Ceramic Society》2002,85(8):1993-1996
The material coefficients of "soft" and "hard" lead zirconate titanate (PZT) ceramics were determined as complex values by the nonlinear least-squares-fitting of immittance data measured for length-extensional bar resonators. The piezoelectric d -constant should be a complex value to obtain a best fitting between observed and calculated results. Because the elastic, dielectric, and piezoelectric losses determined in this process were not "intrinsic" losses, a calculation process to evaluate the "intrinsic" losses was proposed. It was confirmed that the intrinsic losses were smaller than the corresponding extrinsic losses. The intrinsic piezoelectric loss existed in both soft and hard PZTs; ∼50% of the loss of piezoelectric d -constant was derived from the elastic and dielectric losses. The most notable difference between the soft and hard PZTs was observed in their elastic losses. 相似文献
86.
Shizuyo Tanaka Tohru Yamazaki Satoshi Asano Atsushi Mitsumoto Daisuke Kobayashi Naomi Kudo Yoichi Kawashima 《Lipids》2013,48(11):1115-1134
SHR/NDmcr-cp (cp/cp) rats (SHR/NDcp) are an animal model of metabolic syndrome. A previous study of ours revealed drastic increases in the mass of palmitic (16:0), oleic (18:1n-9), palmitoleic (16:1n-7), cis-vaccenic (18:1n-7) and 5,8,11-eicosatrienoic acids in the liver of SHR/NDcp. However, detailed information on the class of lipid accumulated and the mechanism responsible for the overproduction of the accumulated lipid in the liver was not obtained. This study aimed to characterize the class of lipid accumulated and to explore the mechanism underlying the lipid accumulation in the liver of SHR/NDcp, in comparison with SHR/NDmcr-cp (+/+) (lean hypertensive littermates of SHR/NDcp) and Wistar Kyoto rats. In the liver of SHR/NDcp, de novo synthesis of fatty acids (16:0, 18:1n-9 and 16:1n-7) and triacylglycerol (TAG) synthesis were up-regulated and fatty acid β-oxidation was down-regulated. These perturbations of lipid metabolism caused fat accumulation in hepatocytes and accumulation of TAG, which were enriched with 16:0, 18:1n-9 and 16:1n-7, in the liver of SHR/NDcp. On the other hand, no changes were found in hepatic contents of diacylglycerol and unesterified fatty acid (FFA); among FFA, there were no differences in the hepatic concentrations of unesterified 16:0 and stearic acid between SHR/NDcp and two other groups of rats. Moreover, little change was brought about in the expression of genes responsive to endoplasmic reticulum stress in the liver of SHR/NDcp. These results may reinforce the pathophysiological role of stearoyl-CoA desaturase 1 and fatty acid elongase 6 in the liver of SHR/NDcp. 相似文献
87.
The microporous polypropylene sheets were prepared by biaxially stretching polypropylene sheets containing CaCO3 filler (particle size, 0.08–3.0 μm), when the CaCO3 filler content was 59% by weight and the stretching ratio was 2.8 × 1.8. The microstructure of the sheets were investigated in relation to the CaCO3 particle size by a N2 gas permeation method. (1) Effective porosity increases with decreasing mean particle size of filler. (2) The tortuosity factor of the pore is in the range of 25–40 and becomes relatively smaller with decreasing mean particle size of filler. (3) The equivalent pore size becomes relatively smaller with decreasing mean particle size of filler. 相似文献
88.
粒子网格混合方法模拟液滴夹带起始点 总被引:1,自引:0,他引:1
环状流动的特性对反应堆事故工况分析具有重要意义,本研究基于粒子网格混合方法对这一现象中的液滴夹带起始点问题进行了数值分析,利用网格求解流场,利用粒子模拟液膜及液滴的运动,探讨了气水流动大密度比情况下,不同流动方向,不同流体粘度,不同液膜厚度下的液滴夹带所需的临界气相流速,结果同经典关系式进行了对比,吻合良好.这一方法对于反应堆事故中的两相流动研究具有参考意义. 相似文献
89.
Shinichi Sakida Satoshi Hayakawa Toshinobu Yoko 《Journal of the American Ceramic Society》2001,84(4):836-842
The structures of M2 O3 –TeO2 (M = Al and Ga) glasses have been investigated by means of 125 Te, 27 Al, and 71 Ga NMR spectroscopies. The structural units of respective cations in M2 O3 –TeO2 glasses were quantitatively analyzed. The fractions of TeO4 trigonal bipyramid, AlO6 and GaO6 octahedra decreased and those of TeO3 trigonal pyramid, AlO4 , AlO5 , and GaO4 polyhedra increased with increasing M2 O3 content. Based on the local structures around Te, Al, and Ga atoms, the structure models of M2 O3 –TeO2 glasses were proposed. 相似文献
90.
Takahiro Matsumoto Tetsuro Nose Yasuaki Nagata Katsuhiro Kawashima Tastuya Yamada Hidetoshi Nakano Satoshi Nagai 《Journal of the American Ceramic Society》2001,84(7):1521-1525
Young's modulus and Poisson's ratio of SiC ceramics at temperatures >1400°C were obtained using a laser ultrasonics method that included a Fabry-Pérot interferometer (LUFP). At temperatures <1000°C, Young's modulus and Poisson's ratio measured using the LUFP method agreed well with those measured using standard contact methods, such as the resonance method and the ultrasonic pulse method. These results showed that the LUFP method is a powerful tool for measuring high-temperature elastic properties of advanced ceramics in a noncontact manner. 相似文献