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271.
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
272.
Atsushi Sano Masato Kurihara Kazuya Ogawa Tsuyoshi Iijima Satoshi Maruyama 《Journal of power sources》2009,192(2):703-707
The effect of alkali function group contained in electrode binder was investigated. Carboxy methyl cellulose (CMC) improved the initial irreversible capacity loss in graphite negative electrode. Lithium acetate also improved the initial cycle efficiency. On the other hand, ethyl cellulose (EC) and hydroxyl propyl methyl cellulose (HPMC), which do not have a carboxylic group, did not decrease the reductive electrolyte decomposition. After charge and discharge cycle, the surface film composition on the electrode with CMC was less than on the electrode without CMC. This suggests that a carboxylic group in the binder acted as a catalyst and promoted the solid electrolyte interphase (SEI) formation which prevents the excess electrolyte decomposition on the graphite electrode. 相似文献
273.
Masao Kubo Takashi Matsubara Satoshi Shimizu Hiroshi Sato 《Artificial Life and Robotics》2010,15(2):207-211
In this article, a new localization approach for a team of robots that use the emergent properties of their formation is proposed.
Synchronized behavior sometimes generates spin-off effects that include geometric patterns. The question then arises as to
whether it is possible to use these patterns for something important for robots. In this article, Takayama’s control strategy,
which is a target enclosure formation, is discussed. A simple and useful expansion of Monte Carlo localization by the emergent
pattern is proposed. The proposed algorithms are confirmed through a series of computer simulations. 相似文献
274.
1-Naphthyl isocyanide was polymerized with Ni(II) catalyst in a cholesteric matrix at the liquid crystal (LC) temperature range. The resultant polymers showed optical activity. In this reaction, the structural chirality of cholesteric LC effectively functions to impart one-handed helicity on the corresponding polymers as an optically active atropisomer. 相似文献
275.
The entrainment process of agglomerates deposited on plate surfaces by shear flows was simulated using the three-dimensional modified discrete element method (mDEM) and influences of several factors on entrainment process were examined. In the case shear induced force is too weak, deposits are only deformed and particles are barely entrained, however, above some critical value particles are entrained by flows forming agglomerates. It was also clarified that the steric-bulky deposit undergoes the stronger hydrodynamic force and is easy to be entrained. There are two entrainment mechanisms corresponding to the parameter As/A which indicates the relative strength of adhesive force between particle and plate surface to that between particles. In case of large As/A where the adhesion between particle and plate surface is predominant, the number of entrained particles monotonically decreases as As/A increases due to the enhanced binding force. By contrast for small As/A, the number of entrained particles is not heavily dependent on As/A due to the mechanism in which the upstream side of deposit is lifted and the deposit is deformed extensively then large agglomerates are entrained. The boundary between those two entrainment mechanisms exists at As/A=0.5-0.6 which is in good agreement with the theoretical prediction. 相似文献
276.
Randeep Rakwal Ganesh Kumar Agrawal Junko Shibato Tetsuji Imanaka Satoshi Fukutani Shigeru Tamogami Satoru Endo Sarata Kumar Sahoo Yoshinori Masuo Shinzo Kimura 《International journal of molecular sciences》2009,10(3):1215-1225
We report molecular changes in leaves of rice plants (Oryza sativa L. - reference crop plant and grass model) exposed to ultra low-dose ionizing radiation, first using contaminated soil from the exclusion zone around Chernobyl reactor site. Results revealed induction of stress-related marker genes (Northern blot) and secondary metabolites (LC-MS/MS) in irradiated leaf segments over appropriate control. Second, employing the same in vitro model system, we replicated results of the first experiment using in-house fabricated sources of ultra low-dose gamma (γ) rays and selected marker genes by RT-PCR. Results suggest the usefulness of the rice model in studying ultra low-dose radiation response/s. 相似文献
277.
278.
Yasuhiro Date Yumiko Nakanishi Shinji Fukuda Tamotsu Kato Satoshi Tsuneda Hiroshi Ohno Jun Kikuchi 《Journal of Bioscience and Bioengineering》2010,110(1):87-93
We have developed a new approach for monitoring the metabolic dynamics in microbial ecosystems using a combination of DNA fingerprinting and metabolome analysis based on stable-isotope-labeling technologies. Stable-isotope probing of DNA (DNA-SIP) has been used previously for the evaluation of cross-feeding in microbial communities. For the development and validation of our monitoring approach, fecal microbiota were analyzed with stable-isotope-labeled glucose used as the sole carbon source. In order to link the metabolic information and the microbial variability, we performed metabolic–microbial correlation analysis based on nuclear magnetic resonance (NMR) profiles and denaturing gradient gel electrophoresis (DGGE) fingerprints, which successfully identified the glucose-utilizing bacteria and their related extracellular metabolites. Moreover, our approach revealed information regarding the carbon flux, in that the “first” wave of extracellular metabolites secreted by the glucose-utilizing bacteria were incorporated into the “secondary” group of substrate-utilizing bacteria, and that this “secondary” group further produced their own secondary metabolized substrates. Thus, this approach is a powerful tool for monitoring the metabolic dynamics in microbial ecosystems and allows for the tracking of the carbon flux within a microbial community. 相似文献
279.
Atsushi Ohma Tetsuya Mashio Kazuyuki Sato Hiroshi Iden Yoshitaka Ono Kei Sakai Ken Akizuki Satoshi Takaichi Kazuhiko Shinohara 《Electrochimica acta》2011,(28):10832
The biggest issue that must be addressed in promoting widespread use of fuel cell vehicles (FCVs) is to reduce the cost of the fuel cell system. Especially, it is of vital importance to reduce platinum (Pt) loading of catalyst layers (CLs) in the membrane electrode assembly (MEA) of a proton exchange membrane fuel cell (PEMFC). In order to lower the Pt loading of the MEA, mass transport of reactants related to the performance in high current density should be enhanced significantly as well as kinetics of the catalyst, which can result in the better Pt utilization and effectiveness. In this study, we summarized our analytical approach and methods for reduction of Pt loading in CLs. Microstructure, mass transport properties of the reactants, and their relation in CLs were elucidated by applying experimental analyses and computational methods. A simple CL model for I–V performance prediction was then established, where experimentally elucidated parameters of the microstructure and the properties in CLs were taken into account. Finally, we revealed the impact of lowering the Pt loading on the transport properties, polarization, and the I–V performance. 相似文献
280.
Surface of an InAs wetting layer on GaAs(001) preceding InAs quantum dot (QD) formation was observed at 300°C with in situ
scanning tunneling microscopy (STM). Domains of (1 × 3)/(2 × 3) and (2 × 4) surface reconstructions were located in the STM
image. The density of each surface reconstruction domain was comparable to that of subsequently nucleated QD precursors. The
distribution of the domains was statistically investigated in terms of spatial point patterns. It was found that the domains
were distributed in an ordered pattern rather than a random pattern. It implied the possibility that QD nucleation sites are
related to the surface reconstruction domains. 相似文献