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991.
Takashi Ohshima Junji Ipposhi Yasuhito Nakahara Ryozo Shibuya Kazushi Mashima 《Advanced Synthesis \u0026amp; Catalysis》2012,354(13):2447-2452
Direct aminations of allylic alcohols, benzylic alcohols, and benzhydrols with electron‐withdrawing (F, Br, I, NO2, or CN) substituents were efficiently catalyzed by aluminum triflate [Al(OTf)3] to afford the corresponding biarylamines in high yield, and the dibromo‐substituted product was further transformed into letrozole. 相似文献
992.
Keisuke Yoshida Kenji Mishiro Yoshihiro Ueda Takashi Shigeta Takumi Furuta Takeo Kawabata 《Advanced Synthesis \u0026amp; Catalysis》2012,354(17):3291-3298
A highly geometry‐selective organocatalytic acylation of tri‐ and tetra‐substituted 2‐alkylidene‐1,3‐propanediols has been developed. The highly E‐selective acylation of various tetrasubstituted 2‐alkylidene‐1,3‐propanediols was achieved in 96 to >99% selectivity for the first time by a non‐enzymatic protocol. 相似文献
993.
Hisayoshi Soejima Keisuke Tsuge Takashi Yoshimura Kazutaka Sawada Hiroshi Kitagaki 《Journal of the Institute of Brewing》2012,118(3):264-268
A novel breeding strategy for a high tyrosol‐producing sake yeast was developed by isolating an ethanol‐resistant mutant from a tryptophan auxotrophic mutant of a sake brewery yeast. Since tyrosol has antioxidant, cardioprotective and taste‐sharpening effects, increasing the tyrosol level of alcohol beverages could be beneficial in alcohol production. Since the transporters of aromatic amino acids are degraded by several stresses and mutants defective in the synthesis of aromatic amino acids are sensitive to ethanol, it was hypothesized that the degradation of these transporters should be inhibited in ethanol resistant mutants isolated from the auxotrophic mutants of aromatic amino acids, and that the uptake of aromatic amino acids would be increased in the mutants. Consistent with this hypothesis, sake was brewed with the ethanol‐resistant mutant of a tryptophan auxotrophic mutant and the sake was found to contain a lesser content of tyrosine and a higher content of tyrosol relative to the sake brewed with the parental strains. The taste of the sake brewed with the mutant strain could be discriminated from the sake brewed with the parental strains, probably because of the altered concentrations of tyrosol and certain amino acids and organic acids. The results suggest that combining the isolation of an ethanol‐resistant mutant and an auxotrophic mutant is an effective method to breed a brewing strain with a modified metabolism of these substances. Copyright © 2012 The Institute of Brewing & Distilling 相似文献
994.
Mikihiko Yoshida Takashi Hishiyama Masako Ogawara Koji Fuse Mitsuaki Mori Tomoji Igarashi Makoto Taniguchi 《Food chemistry》2012
Certain foodstuffs exhibit matrix interference effects on the vitamin B1 analysis prescribed in the official methods of the European Union, AOAC International, and Japan. In this study, we demonstrated that one of the problematic polyphenols in green tea or cocoa was tannin. For these matrices, thiamine was found to interact with tannin in the extraction step and was thus removed by filtration as a residue. To resolve the matrix interference, we proposed lowering the pH of the extraction solution by adding hydrochloric acid after the enzyme reaction. High precision (2–3% RSDr) and good recovery (98.3–103%) were obtained with reference materials using the proposed method. We also confirmed the equivalence of the obtained data from the proposed method and the Japanese official method for nutritional labeling. From these results, the method was found to be effective for vitamin B1 analysis regardless of the presence of interference matrices. 相似文献
995.
Yasutoshi Kasahara Masashi Kato Satoshi Watanabe Makio Iwahashi Rieko Wakamatsu Takashi Suzuki Akinori Kanetani Takaaki Kano Takamitsu Tamura 《Journal of the American Oil Chemists' Society》2012,89(7):1223-1229
Mineral oil is commonly used as an electrical insulating oil in transformers because of its relatively high electrical insulating
ability and fluidity. Considering the depletion of resources and environmental problems, however, fatty acid esters synthesized
from natural plant oils are attracting attention as an environmentally friendly insulating oil. In addition, fatty acid esters
such as methyl octanoate, methyl dodecanoate, 2-ethylhexyl octanoate, and 2-ethylhexyl dodecanoate have high fluidity, and
also show excellent moisture tolerance against dielectric breakdown compared to mineral oil. In the present study, to clarify
the reason for the superior moisture tolerance of fatty acid esters, the status of dissolved water in esters is investigated
with IR spectroscopic measurements and density functional theory (DFT) calculations. It is revealed that water molecules in
fatty acid esters are trapped by the ester moiety of fatty acid esters. As a result, fatty acid esters have a higher moisture
tolerance against dielectric breakdown than mineral oil. 相似文献
996.
To examine the functional role of hyperpolarization‐activated and cyclic nucleotide‐gated (HCN) current observed in mesencephalic dopaminergic neurons, we constructed a conductance‐based model that can mimic the electrical properties obtained in electrophysiological recordings of rat brain slices. In the model, blocking the HCN current resulted in a reduction of spontaneous firing rate and a change in the properties of autonomous pacemaking. In addition, reduced one‐dimensional phase equations and their coupled oscillators were analyzed. The analysis indicated that HCN channels can regulate the extent of synchronization of coupled dopaminergic neurons through gap–junction connections. Thus, the HCN current can effectively shape the autonomous and cooperative firing of dopaminergic neurons in the midbrain. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
997.
Takatoshi Shindo Tsuguhiro Takahashi Tatsuki Okamoto Takashi Kuraishi 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(5):450-453
Application of Bayes' theorem for the evaluation of diagnostic results of electric facilities is described. A concept of risk assessment method based on the diagnosis results is proposed and the effects of various parameters on the risk are clarified. Based on these results, a rational renewal scheme using diagnostic results is proposed. In addition, the prior probability based on the data of actual facilities is investigated and it is found that the data available so far is insufficient and more data are required for the detailed analysis. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
998.
Masaki Amemiya Ken‐ichi Watabe Tomonari Suzuyama Takashi Naito Hidemi Tsuchida 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(Z1):S187-S189
Stable timing distribution is a key technology for the many fields that use timing signals for synchronization. The frequency of the timing signal depends on the field and multiple timing signals are sometimes required. In our DWDM‐based timing distribution system, phase deviation is detected by high‐speed round‐trip signal (10 GHz signal is used as this control signal). Fiber stretchers are controlled so as to minimize the phase deviation of the control signal. Multiple signals and the control signal are densely multiplexed and transmitted through the same stretchers. Therefore, the transmission of all signals is stabilized. This configuration provides a flexible platform for distributing various RF or microwave signals. As an example of arbitrary timing signals, a 1 GHz signal is transmitted over a length‐stabilized 400‐m fiber for more than 1 day. The recorded propagation time fluctuations are 10.4 and 2.8 fs rms for the 1 and 10 GHz signals, respectively. The Allan deviations are 2.7 × 10−19 (1 GHz) and 6.0 × 10−20 (10 GHz) for the averaging time of 105 s. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
999.
To investigate the effect of molecular structure on macroscopic flow behavior of polymeric liquid, attempts have been made to embed the microscopic information into the flow simulation. Constitutive equation based on the theory of polymer dynamics is ideal but the theory is still under development. The CONNFFESSIT approach (where microscopic simulation is embedded into calculation grid in macroscopic simulation) is another promising direction but the computational cost is not practical yet. In this study, we propose another simple method using parameter-based bridging where the parameters for phenomenological constitutive equations in macroscopic flow simulation are obtained from coarse-grained molecular simulation. As an example, we performed a simulation of injection molding and examined the effect of molecular weight on warpage of the molded product. We used the primitive chain network simulation to calculate linear viscoelasticity of linear monodispersed polystyrenes from molecular weight. The obtained linear viscoelasticity was converted into the relaxation spectrum and into the flow curve to be used in the macroscopic simulations. From the flow curve, the parameters of an inelastic non-Newtonian constitutive equation were obtained and used for the simulation of filling process. The relaxation spectrum was used to calculate residual stress from the flow profile in the filling process. From the residual stress and thermal shrinkage, warpage of the product was obtained. For the examined thin plate product, significant change in the warpage direction was demonstrated according to the molecular weight of the material. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
1000.
Tomoya Higashihara Cenyao Zhang Akimitsu Tsukuda Takashi Ochi Mitsuru Ueda 《应用聚合物科学杂志》2012,124(5):4398-4402
The direct polycondensation of isophthalic acid with a mixture of 1,3‐phenylenediamine (m‐PDA) and 3,4′‐diaminodiphenyl ether (3,4′‐ODA) could be successfully performed in the bulk to afford the expected co‐aramids for the first time. The co‐aramids with low molecular weights and 3,4′‐ODA contents higher than 50 mol% display excellent thermoplasticity and melt‐drawing property. Indeed, several meters long filaments with 12 μm diameter could be produced. In addition, the environmentally friendly method for the preparation of aramid materials as well as the demonstration of their filament formation will open up the new possibility to prepare aramid fibers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献