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331.
332.
Teruhisa S. Komatsu Naoko Nakagawa Shin-Ichi Sasa Hal Tasaki 《Journal of statistical physics》2009,134(2):401-423
Recently a novel concise representation of the probability distribution of heat conducting nonequilibrium steady states was
derived. The representation is valid to the second order in the “degree of nonequilibrium”, and has a very suggestive form
where the effective Hamiltonian is determined by the excess entropy production. Here we extend the representation to a wide
class of nonequilibrium steady states realized in classical mechanical systems where baths (reservoirs) are also defined in
terms of deterministic mechanics. The present extension covers such nonequilibrium steady states with a heat conduction, with
particle flow (maintained either by external field or by particle reservoirs), and under an oscillating external field. We
also simplify the derivation and discuss the corresponding representation to the full order. 相似文献
333.
Dohi T Morimoto K Takenaga N Maruyama A Kita Y 《Chemical & pharmaceutical bulletin》2006,54(11):1608-1610
The facile and clean direct cyanating reaction of pyrroles and thiophenes has been achieved using a recyclable hypervalent iodine(III) reagent 1b by a simple solid-liquid separation of the products and the reagent. 相似文献
334.
By fractional precipitaion of bacterial copolyesters, it has been strongly suggested that the bacterial PHA copolymer normally has broad and/or multimodal chemical composition distribution (CCD). In this paper, we try to review the works on the blends of two bacterial polyesters in order to accumulate knowledge on the relation between CCD and various properties required for the practical application of bacterial copolymers. Phase structures of the blends of poly(3-hydroxybutyrate) [PHB] and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHB-HV] and crystallization kinetics of the blends of PHB-HV and poly(3-hydroxybutyrate-co-3-hydroxypropionate) [PHB-HP] are described. 相似文献
335.
[CuL(SC(6)F(5))] (1) (L = hydrotris(3,5-diisopropyl-1-pyrazolyl)borate anion) has been reported as a good model for blue copper proteins [Kitajima, N.; Fujisawa, K.; Tanaka, M.; Moro-oka, Y. J. Am. Chem. Soc. 1992, 114, 9232-9233]. To obtain more structural and spectroscopic insight, the first-row transition metal(II) substituted complexes of Cu(II) (1) to Mn(II) (2), Fe(II) (3), Co(II) (4), Ni(II) (5), and Zn(II) (6) were synthesized and their crystal structures were determined. These model complexes have a distorted tetrahedral geometry arising from the tripodal ligand L. The d value, which is defined by the distance from the N(2)S basal plane to the metal(II) ion, and the bond angles such as N-M-N and S-M-N are good indicators of these structural distortions. The obtained complexes were characterized by UV-vis absorption, EPR, NMR, far-IR, and FT-Raman spectroscopies and electrochemical and magnetic properties. In UV-vis absorption spectra, the sulfur-to-metal(II) CT bands and the d-d transition bands are observed for 1 and 3-5. For 1, the strong sulfur to Cu(II) CT band at 663 nm, which is one of the unique properties of blue copper proteins, is observed. The CT energies of the Fe(II) (3), Co(II) (4), and Ni(II) (5) complexes are shifted to higher energy (308 and 355 nm for 3, 311 and 340 nm for 4, 357 and 434 nm for 5) and are almost the same as the corresponding Co(II)- and Ni(II)-substituted blue copper proteins. In the far-IR spectra, three far-IR absorption bands for 2-6 at ca. 400, ca. 350, and ca. 310 cm(-1) are also observed similar to those for 1. Other properties are consistent with their distorted tetrahedral geometries. 相似文献
336.
Takeda T Shimane K Ito K Saeki N Tsubouchi A 《Chemical communications (Cambridge, England)》2002,(17):1974-1975
Ketones, aldehydes, esters and lactones are transformed into olefins by treatment with the organotitanium species formed from alkyl halides and titanocene(II). 相似文献
337.
Solid-state structures and enzymatic degradability have been investigated for cocrystallized blends between poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [PHBV] and poly(3-hydroxybutyrate-co-3-hydroxypropionate) [PHBP]. From wide-angle X-ray diffraction patterns, small-angle X-ray scattering data, and the comparison of the enzymatic degradability of these blends, the solid-state structures of PHBV/PHBP blend samples, in which the PHBV component has higher isothermal crystal growth rate (G) value than the PHBP one, might be similar to those of the component PHBVs; while those of the PHBP/PHBV blend samples, in which PHBP component has higher G value, were similar to the component PHBPs. Normalized one-dimensional correlation functions gamma(x) of PHBV/PHBP binary blends crystallized at 90 degrees C. 相似文献
338.
Masayuki Sato Yoshito Abe Kazuhisa Takayama Keiko Sekiguchi Chikara Kaneko Naoko Inoue Toshio Furuya Noriyoshi Inukai 《Journal of heterocyclic chemistry》1991,28(2):241-252
The use of rigid spirocyclic dioxinones having 1-menthone as the chiral auxiliary as the enones in the photo[2 + 2]cycloaddition reactions opened novel methods for obtaining enantiomerically pure compounds, such as iridoids. Convex side preference of the sofa-conformation of these dioxinones in the photoaddition to cyclopentene increases up to 100% by introducing either a bulky substituent or 5-hexenyl group at the 3-position to these dioxinones and, hence, highly asymmetric inter- and intramolecular de Mayo reactions have been disclosed. 相似文献
339.
340.
Pattern classification is one of the main themes in pattern recognition, and has been tackled by several methods such as the statistic one, artificial neural networks, mathematical programming and so on. Among them, the multi-surface method proposed by Mangasarian is very attractive, because it can provide an exact discrimination function even for highly nonlinear problems without any assumption on the data distribution. However, the method often causes many slits on the discrimination curve. In other words, the piecewise linear discrimination curve is sometimes too complex resulting in a poor generalization ability. In this paper, several trials in order to overcome the difficulties of the multi-surface method are suggested. One of them is the utilization of goal programming in which the auxiliary linear programming problem is formulated as a goal programming in order to get as simple discrimination curves as possible. Another one is to apply fuzzy programming by which we can get fuzzy discrimination curves with gray zones. In addition, it will be shown that using the suggested methods, the additional learning can be easily made. These features of the methods make the discrimination more realistic. The effectiveness of the methods is shown on the basis of some applications. 相似文献