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61.
A. Meddour J. Courtieu W. Abdelhadi S. Guermouche M. H. Guermouche 《Chromatographia》1996,43(7-8):387-392
Summary Comparative gas chromatographic properties of two thermotropic Poly(L-glutamates) with long alkyl side chains (10 and 16 carbons called Poly 10 and Poly 16 respectively) are studied.Their thermal properties were established with differential scanning calorimetry (DSC) and gas chromatography. They present a cholesteric liquid crystal in a large temperature range.The chromatographic separation abilities of the two polymers in the liquid crystal state were studied using capillary glass columns. Interesting analytical performances were obtained in different fields: isomeric separation of alkanes, aromatics, polyaromatics, volatile aroma compounds and cis and trans isomers. Some differences were noticed in their behaviours; 2 and 3-methyloctane and xylene isomers are separated only on Poly 10 while limonene and eucalyptol are separated only on Poly 16. 相似文献
62.
本文通过将使用时间在可能发生故障的时刻划分成时间区间,对修如旧模型下的多部件系统,在修理延迟条件下,对各类故障在同一时间区间里相容的条件下导出了任意给定时刻设备的可用度函数,并对文[3]中的算法做了改进,得到了更精确更合理的结果 相似文献
63.
The magnetic hyperfine interaction of 60Co in the completely miscible alloy Co
x
Pd1−x
was investigated for different values of x by measuring the nuclear orientation of 60Co as function of temperature and by nuclear magnetic resonance of the oriented 60Co nuclei. A broad resonance signal of Gaussian shape could be observed down to x=60%. The dependence of the mean magnetic hyperfine field on the Co concentration was observed to be linear very similar to
that of experimental values of the magnetic moment per atom in the literature. The magnetic hyperfine field and its broad
distribution are discussed in a simple model with RKKY interaction.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
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王永刚 龚靖School of Civil Engineering Mechanics Xi'an Jiaotong University Xi'an P.R.China Department of Civil Engineering Northeast China Institute of Electric Power Jilin P.R.China 张景绘School of Civil Engineering Mechanics Xi'an Jiaotong University Xi'an P.R.China 《应用数学和力学(英文版)》2004,(8)
IntroductionThestudiedobjectintheclassicstructuredynamicsisthepassivestructureswhicharechangedintoactivestructurewhencontroldevicesorsmartmaterialsareintroducedintoandthecontrolfunctionisapplied .Anactivestructureisgenerallycalledactivesystem .Asforthedefinitionofactivestructure ,itistheconceptofworthydiscussion[1].Thedefinitionshouldbebecomingrigorouswiththestudyontheactivestructuraldynamics.Withincertaincategoryofactivestructuresinpaper (Ⅰ ) [2 ],someattributesaboutthemodesoflinearactivest… 相似文献
66.
A chirped pulse microwave spectrometer has been used to record microwave spectra of the 35Cl and 37Cl isotopologues of methyl chlorodifluoroacetate, CClF2C(O)OCH3, between 8 GHz and 16 GHz. The target compound was spectroscopically examined as it participated in a supersonic expansion of argon. Only one conformer was observed. The rotational spectra were recorded with sufficient resolution to observe (i) splittings due to the internal rotation of the methyl group, and (ii) splittings from the coupling of the chlorine quadrupolar nucleus. A total of 785 transitions have had quantum numbers assigned. Analysis of the spectra observed has produced an experimental barrier to the methyl group internal rotation, V3, of 370(2) cm−1. It is noted that this barrier is a little lower than that determined for methyl acetate [V3 = 425 cm−1, J. Sheridan, W. Bossert and A. Bauder, J. Mol. Spectrosc., 80 (1980) 1-11], and this is rationalized through a comparison of molecular structures. Lastly, all components of both the 35Cl and 37Cl chlorine nuclear electric quadrupolar coupling tensor have been determined. 相似文献
67.
In this article, both the eigenvectors and the eigenvalues of the q‐Bernstein operators have been studied. Explicit formulae are presented for the eigenvectors, whose limit behavior is determined both in the case 0 < q < 1 and in the case q > 1. Because the classical case, where q = 1, was investigated exhaustively by S. Cooper and S. Waldron back in 2000, the present article also discusses the related similarities and distinctions with the results in the classical case. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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