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We derive a moderate deviation principle for the lower tail probabilities of the length of a longest increasing subsequence in a random permutation. It refers to the regime between the lower tail large deviation regime and the central limit regime. The present article together with the upper tail moderate deviation principle in Ref. 12 yields a complete picture for the whole moderate deviation regime. Other than in Ref. 12, we can directly apply estimates by Baik, Deift, and Johansson, who obtained a (non-standard) Central Limit Theorem for the same quantity. 相似文献
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[reaction: see text] A new method to facilitate the separation of diastereomeric syn- and anti-1,3-diols is described. The method relies on the different hydrolysis rates of the corresponding diastereomeric acetonides. Treatment of a dichloromethane solution of syn- and anti-1,3-diol-acetonide with a catalytic amount of diluted aqueous hydrochloric acid leads to the selective cleavage of the anti diastereomer. The resulting anti-1,3-diol can be easily separated from the unchanged syn-1,3-diol-acetonide. 相似文献
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Maarten C. Krol Cornelis J. M. Huige Cornelis Altona 《Journal of computational chemistry》1990,11(7):765-790
The anomeric effect of the functional groups X = C?N, C?CH, COOH, COO?, O? CH3, NH2, and NH+3 has been studied with ab initio techniques. Geometry effects upon rotation around the central C? O bond in X? CH2? O? CH3 have been compared in the various compounds. The energy differences between the conformers with a gauche and trans (X? C? O? C) arrangement were calculated at the 6-31G* level in the fully optimized 4-21G geometries. Energy differences calculated at the 4-21G level appeared not to be reliable, especially for the groups X that contain non-sp3 hybridized atoms. The 6-31G* energy differences indicate a normal anomeric effect for X = COO?, O? CH3, and NH2(g+) (ca. 13 kJ/mol) and a small anomeric effect for X = COOH, C?N, and C?CH (ca. 6 kJ/mol). For X = NH2(t) and NH+3 a reverse anomeric effect occurs. These observations are in line with experimental results and evidence is given for a competition among various stereoelectronic interactions that occur at the same anomeric center. Geometry variations can be understood in terms of simple rules associated with anomeric orbital interactions. Trends followed when the group X is varied cannot be related in a straightforward way to the energy differences between the trans and the gauche forms in these compounds. Only the variation in the gauche torsion angle X? C? O? C follows roughly the same trend. 相似文献
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A. I. Druzhinina O. V. Krol’ A. A. Efimova R. M. Varushchenko L. L. Gervits 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(11):1742-1748
The borling temperatures of perfluoro-2,4,6,9,11,13-hexaoxy-n-tetradecane, perfluoro-2,4,6,8,11,13,15,17-octaoxy-n-octadecane, and perfluoro-2,4,6,8,11,13,15,17,19,21-decaoxy-n-docosane were determined by comparative ebulliometry over the saturated vapor pressure range 6.2–101.6 kPa. The heat capacity of perfluoro-2,4,6,8,11,13,15,17-octaoxy-n-octadecane was studied by adiabatic calorimetry over the temperature range 5.3–371.2 K. The densities of the substances at 296–338 K were measured in quartz pycnometers. The data obtained were used to calculate the normal boiling points, enthalpies of vaporization, critical parameters, and thermodynamic functions (entropy, enthalpy, and Gibbs energy) of the polyethers studied. 相似文献
7.
Dieter Naumann Prof. Dr. Wieland Tyrra Dr. Hendrik T. M. Fischer Silke Kremer 《无机化学与普通化学杂志》2007,633(4):527-528
Tetrakis(pentafluorophenyl)tellurium(IV), Te(C6F5)4, was prepared from the reaction of TeCl4 and Mg(C6F5)Br. Crystallization of the crude product from n‐pentane at ?25 °C gave suitable single crystals. The title compound crystallizes in the monoclinic space group P21/c (Z = 8) with two independent molecules per unit cell. 相似文献
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