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121.
Poompat Rattanatraicharoen Keiko Shintaku Kazuhiro Yamabuki Tsutomu Oishi Kenjiro Onimura 《Polymer》2012,53(13):2567-2573
The novel optically active (S)-4-benzyl-2-(ethynylphenyl)-oxazoline (BnEPhOx) was successfully prepared and polymerized using rhodium catalyst ([Rh(nbd)Cl]2) to obtain the moderate molecular weight poly(phenylacetylene)s bearing chiral oxazoline derivatives with high yields (≥90%). The 1H NMR spectra demonstrated that the resulting polymers had high stereoregular structures. Moreover, the poly(phenylacetylene)s bearing chiral oxazoline exhibited better thermal stability than poly(phenylacetylene). The resulting polymers showed higher absolute values of optical specific rotation than the monomer. The polymers also exhibited intense CD signal in the region of the π-π1 band of the conjugated polyacetylene backbone in chloroform solution. The results of specific rotation and CD spectroscopy indicated that all the polymers adopted higher-order structure with predominantly one-handed screw sense.In addition, the resulting polymers emitted fluorescence under UV irradiation. 相似文献
122.
123.
Yasuhito Ishigaki Yuka Nakamura Teruaki Takehara Noriko Nemoto Takayuki Kurihara Hironori Koga Hideaki Nakagawa Tsutomu Takegami Naohisa Tomosugi Shichiro Miyazawa Susumu Kuwabata 《Microscopy research and technique》2011,74(5):415-420
Ionic liquid is a kind of salt that stays in a molten state even at room temperature. It does not vaporize at all in vacuum and facilitates electrical conductivity to the sample surfaces for observations with a scanning electron microscope (SEM). In this study, we used an ionic liquid in SEM for the first time to observe fixed human culture cells. The condition for the cell culture using wrapping sheets and SEM settings were varied to elucidate the optimized protocol. Compared to samples prepared by the conventional way, the ionic liquid‐treatment of samples gave SEM images of the cellular ultra structures in more detail, enabling observation of microvilli that made bridges between separated cells. In addition, the ionic liquid treatment is less time consuming as well as less laborious compared with the conventional way that includes dehydration, drying, and conductivity treatments. Totally, we concluded the ionic liquid is a useful reagent for SEM sample preparation. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc. 相似文献
124.
125.
Onoue Y Shindo R Teranishi H Furukawa I Hasegawa Y Maruyama T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(4):239-242
The efficacy of Baird-Parker (BP) agar, mannitol-salt-egg yolk (MSEY) agar and mannitol salt (MS) agar in detecting Staphylococcus aureus FRI-100 heated at 52 degrees C for 20 min in 100 mmol/L potassium phosphate buffer was determined. Brain heart infusion agar with 1% pyruvate (BHIP agar) supported the highest recovery of injured cells and was used as the control medium. Of the three selective media, significantly higher recovery of heat-injured cells was observed on BP agar than MSEY agar, and the poorest recovery was observed on MS agar (p < 0.05). Low recovery of unheated cells was obtained for MS compared with other media (p < 0.05). A reduction in populations occurred gradually in reagent-grade water stored for 14 days at -20 degrees C. There was no significant difference between BHIP agar and MS agar in the number of freeze-injured cells recovered from 1 to 14 days. 相似文献
126.
Hemmi H Yamashita S Nakayama T Nishino T 《Journal of Bioscience and Bioengineering》2002,93(5):515-518
It is known that 1-deoxy-D-xylulose taken up by Escherichia coli is used as the precursor of the compounds synthesized via the non-mevalonate pathway, such as isoprenoids, probably after conversion into 1-deoxy-D-xylulose 5-phosphate. In this report, we show that a novel phospho(enol) pyruvate-dependent phosphotransferase system catalyzes the uptake and phosphorylation of 1-deoxy-D-xylulose. 相似文献
127.
Yusuke Tanimura Tsutomu Ikegami Hidemoto Nakada Yoshio Tanaka Satoshi Sekiguchi 《Journal of Grid Computing》2006,4(2):145-157
A task parallel application is implemented with Ninf-G, a GridRPC system. A series of experiments are conducted on the Grid testbed in Asia Pacific for three months. Through tens of long executions, typical fault patterns were collected, and instability of the network throughput was determined to be a major reason of the faults. Several important points are stressed to avoid task throughput decline due to the fault-recovery operations: Timeout minimization for fault detection, background recovery, redundant task assignments, and so on. This study also issues a steer for design of the automated fault-tolerant mechanism in an upper layer of the GridRPC framework. 相似文献
128.
A coterie is a set of subsets (called quorums) of the processes in a distributed system such that any two quorums intersect with each other and is mainly used to solve the mutual exclusion problem in a quorum-based algorithm. The choice of a coterie sensitively affects the performance of the algorithm and it is known that nondominated (ND) coteries achieve good performance in terms of criteria such as availability and load. On the other hand, grid coteries have some other attractive features: 1) a quorum size is small, which implies a low message complexity, and 2) a quorum is constructible on the fly, which benefits a low space complexity. However, they are not ND coteries unfortunately. To construct ND coteries having the favorite features of grid coteries, we introduce the transversal merge operation that transforms a dominated coterie into an ND coterie and apply it to grid coteries. We call the constructed ND coteries ND grid coteries. These ND grid coteries have availability higher than the original ones, inheriting the above desirable features from them. To demonstrate this fact, we then investigate their quorum size, load, and availability, and propose a dynamic quorum construction algorithm for an ND grid coterie. 相似文献
129.
Y. Ukai T. Ohyama L. Fennell Y. Kato M. Paukshto P. Smith O. Yamashita S. Nakanishi 《Journal of the Society for Information Display》2005,13(1):17-24
Abstract— A thin‐crystalline‐film (TCF) polarizer has been developed which can be used internally in liquid‐crystal‐display cells. Based on this material, a manufacturing process has been developed for the fabrication of monochrome LCDs with internal polarizers. A new TCF polarizer material and coating equipment, developed to realize a high‐performance color TFT‐LCD, are discussed. 相似文献
130.
We present a short overview of the critical temperature correlations with different parameters for low and high T c superconductors. The overview underlines the importance of crystalline structure in determining the critical temperature value. The structure of copper-based superconductors is studied in comparison with low-temperature superconductors and a new correlation of the transition temperature is found. Namely, the layered structure, more exactly a certain distribution of the mass of the ions along the c-axis is the key factor in determining the “intrinsic” critical temperature, parameter introduced by Kresin et al. [4]. 相似文献