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51.
Masashi Kijima Hideki Hasegawa Hideki Shirakawa 《Journal of polymer science. Part A, Polymer chemistry》1998,36(15):2691-2698
Three liquid crystalline N-substituted pyrroles were synthesized from 6-(1-pyrrolyl)hexanol with phenolic derivatives having a mesogenic core of cyclohexylbenzene or biphenyl by Mitsunobu reaction. These pyrroles had two anodic peaks at 1.4 and 1.8 V (vs. SCE). The former was due to an oxidation of the pyrrole moiety and the latter was due to an oxidation of the mesogenic moiety. These pyrrole monomers were polymerized by electrochemical and chemical methods. The potentiostatic method and the chemical method using FeCl3 gave a soluble and fusible polymer, respectively. A polymer having a mesogenic core of cyclohexyl benzene obtained by the chemical method and a polymer having a mesogenic core of biphenylketone obtained by the potentiostatic method had a liquid-crystalline phase. The phase was identified as smectic A by polarizing microscopy and XRD analysis. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2691–2698, 1998 相似文献
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In this paper, we propose a fully polynomial-time randomized approximation scheme (FPRAS) for a closed Jackson network. Our
algorithm is based on the Markov chain Monte Carlo (MCMC) method. Thus our scheme returns an approximate solution, for which
the size of the error satisfies a given bound. To our knowledge, this algorithm is the first polynomial time MCMC algorithm
for closed Jackson networks with multiple servers. We propose two new ergodic Markov chains, both of which have a unique stationary
distribution that is the product form solution for closed Jackson networks. One of them is for an approximate sampler, and
we show that it mixes rapidly. The other is for a perfect sampler based on the monotone coupling from the past (CFTP) algorithm
proposed by Propp and Wilson, and we show that it has a monotone update function. 相似文献
55.
Ohne Zusammenfassung 相似文献
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57.
Masaaki Kijima Kei-Ichiro Nakagawa Takashi Namatame 《Computational & Mathematical Organization Theory》2000,6(1):7-27
This paper studies a competitive price equilibrium in the market of a product category where consumers are homogeneous with a reservation utility below which they will not purchase the product. The impact of the reservation utility on the price equilibrium is of particular interest, because the reservation utility may change according to the business cycle and economic environments. Using multinomial logit model to describe market response, we study the comparative statics of the prices, profits and market shares of firms, each of which produces one brand in the product category, with respect to the reservation utility in the Nash equilibrium. It is shown that, as the reservation utility increases, the prices as well as the profits at Nash equilibrium decrease. Also, in the case of duopoly market, the firm with lower cost structure will increase its market share as the reservation utility increases. 相似文献
58.
ZhongMin Geng Go Sato Kazuhiro Marumoto Masashi Kijima 《Journal of polymer science. Part A, Polymer chemistry》2016,54(21):3454-3461
Donor–π–acceptor type fluorene‐based copolymers with a sulfone unit were designed and synthesized for application in efficient pure‐blue light emitting. The electroluminescence behaviors of these copolymers were investigated by fabricating light‐emitting diodes and electrochemical cell devices. The former device little functioned but the latter worked well. The electrochemical cell devices having a configuration of ITO/PEDOT:PSS/copolymer:ionic liquid/Al exhibited purplish blue electroluminescence with an emission maximum at 434 nm (CIE coordinates (x, y) = (0.17, 0.10)) measured at 7 V. The initial positive scan of the D–π–A polysulfone based light emitting electrochemical cell with a sweep rate of 0.1 V s?1 afforded a maximum luminance of 1080 cd m?2 with a current efficiency of 1.96 cd A?1 at an operating voltage of 12.5 V. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3454–3461 相似文献
59.
The rheological properties and particle size distributions of cocoa beverage as well as aggregate structures of solid particles were studied to elucidate the effects of microcrystalline cellulose (MCC) on suspension stability of solid particles in cocoa beverage. Fluidity curve, dynamic viscoelasticity, particle size distribution, and SEM observation were made for beverage samples containing 0.1–0.5 wt% MCC and 11 model samples with various combinations of six ingredients. This revealed that cocoa and MCC particles are highly cohered into an aggregate and the aggregated particles further interact weakly with the milk component, leading to stabilization of the whole system of cocoa beverage. 相似文献
60.
Shingo Sato Hiroaki Iijima Norihiro Haga Kohbun Osono Hitoshi Mizuguchi Tatsuro Kijima 《Supramolecular chemistry》2013,25(1):39-46
The Calix[4]arene 1 including two alternately arranged phloroglucinols and p-tert-butylphenols was synthesized via the “3+1” coupling procedure, and its pKa values were estimated to be 3–4 and 7.5, while those of the other six phenolic hydroxyls were approximately 11. Its UV–vis spectrum at pH 11 and 1H and 13C NMR spectra in NaOD-D2O solution (pH 12.8) showed a dramatic change like those of the phloroglucinol when compared to those in acidic or neutral solution, which suggests a change in the phloroglucinol moiety to the keto-form. During the solvent extraction for alkali metal species using 1, Li+ was only extracted in the low yield of 15% at pH 11. The cyclic voltammetry study of 1 was used to compare it with the phloroglucinol and p-tert-butylphenol. The redox potential of the corresponding two phloroglucinols was observed in 1. 相似文献