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11.
Tetsuo Kusumoto Ken-Ichi Sato Kumiko Ogino Tamejiro Hiyama Sadao Takehara Masashi Osawa 《Liquid crystals》2013,40(3):727-732
Abstract New chiral dopants β-hydroxy ketones 1, 1,3-diols 2, 1,3-dioxanes 3 and 1,3-dioxan-2-ones 4 were designed and synthesized. Reaction of (R)-1,2-epoxyoctane with carbanions derived from 2-(4-substituted phenyl)-1,3-dithianes followed by hydrolysis of the resulting hydroxy dithianes afforded 1. Reduction of 1 gave the diols 2, which yielded 3 upon acetalization and 4 upon carbonation. The syn isomers of 2, 3, and 4 exhibited larger spontaneous polarizations, when applied as chiral dopants, than the anti isomers or hydroxy ketones 1. 相似文献
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A previously proposed model describing the trapping site of the interstitial atomic hydrogen in borate glasses is analyzed. In this model the atomic hydrogen is stabilized at the centers of oxygen polygons belonging to B–O ring structures in the glass network by van der Waals forces. The previously reported atomic hydrogen isothermal decay experimental data are discussed in the light of this microscopic model. A coupled differential equation system of the observed decay kinetics was solved numerically using the Runge Kutta method. The experimental untrapping activation energy of 0.7×10−19 J is in good agreement with the calculated results of dispersion interaction between the stabilized atomic hydrogen and the neighboring oxygen atoms at the vertices of hexagonal ring structures. 相似文献
13.
Sadao Takagi Mune Maeda 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):775-780
The enthalpies of transfer of cyclohexanol from aqueous to aqueous - or -cyclodextrin solutions have been measured at various mole fractions at 298.15 K on a rocking twin-microcalorimeter of heat-conduction type and the molar enthalpies, Gibbs energies, and entropies of inclusion in the aqueous solutions have been determined by the method proposed by the authors [Netsu Sokutei
10, 103 (1983)], to elucidate the driving force of the molecular inclusion. Discussions are given for all the systems obtained by the authors, concluding that the driving force is the enhancement of the entropy.Calorimetric studies on molecular inclusion V. 相似文献
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For square contingency tables with ordered categories, Tomizawa (Calcutta Stat Assoc Bull 43:123–125, 1993a; Sankhyā Ser B 60:293–300, 1998) gave theorems that the marginal homogeneity (MH) model is equivalent to certain two or three models holding simultaneously. This paper proposes a generalized MH model, which describes a structure of the odds that an observation will fall in row category i or below and column category i + 1 or above, instead of in column category i or below and row category i + 1 or above. In addition, this paper gives the theorems that the MH model is equivalent to the generalized MH model and some models holding simultaneously whose each indicates: (1) the equality of m-order moment of row and column variables, (2) the equality of skewness of them and (3) the equality of kurtosis of them. When the MH model fits the data poorly, these may be useful for seeing the reason for the poor fit; for instance, the poor fit of the MH model is caused by the poor fit of the equality of row and column means rather than the generalized MH model. Examples are given. 相似文献
18.
Inoue K Kitahara K Aikawa Y Arai S Masuda-Hanada T 《Molecules (Basel, Switzerland)》2011,16(7):5905-5915
To investigate the separations of all aldopentoses (ribose, arabinose, xylose and lyxose) and aldohexoses (glucose, galactose, allose, altrose, mannose, gulose, idose and talose) on the D? stationary phase prepared by the reaction of chloromethylated styrene-divinylbenzene copolymer and N,N,N',N'-tetramethyl-1,6-diaminohexane, we examined the effect of varying the concentration of the NaOH eluent on the elution orders. Separations of these aldoses were achieved using a 20 mM NaOH eluent. The elution behaviors of the aldoses were probably due to not only the individual pK(a) values, but also the chemical structures of the cyclic aldoses. 相似文献
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Summary The concepts of the asymptotic maximum likelihood estimates—AMLEs in short—and their asymptotic identity are introduced in
section 1. They seem to be more adequate than the usual one for uses in the large sample theory. The AMLE is a slightly weakened
version of the usual maximum likelihood estimate and therefore it should have a bit wider applicability than the original
one. The asymptotic normality of a consistent AMLE and Wilks’ theorem concerning the asymptotic distribution of the statistic
—2 log λ, where λ is the likelihood ratio, can be obtained under the regularity conditions due to Doob in section 2. A set
of conditions which assure the existence of a unique and consistent AMLE is presented in section 3 and in the final section
4 the proof of the existence of the unique and consistent AMLE under those conditions is given.
This work has been motivated by the work of Ogawa, Moustafa and Roy [3]. 相似文献