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S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
3.
A pronounced step-like (kink) behavior in the temperature dependence of resistivity ρ(T) is observed in the optimally doped Sm1.85Ce0.15CuO4 thin films around T
sf = 87 K and attributed to the manifestation of strong-spin fluctuations induced by Sm3+ moments with the energy ħωsf = k
B
T
sf ≃ 7 meV. The experimental data are found to be well fitted by the residual (zero-temperature) ρres, electron-phonon ρe-ph(T) = AT, and electron-electron ρe-e(T) = BT
2 contributions in addition to the fluctuation-induced contribution ρsf(T) due to thermal broadening effects (of the width ωsf). According to the best fit, the plasmon frequency, impurity scattering rate, electron-phonon coupling constant, and Fermi
energy are estimated as ωp = 2.1 meV, τ
0
−1
= 9.5 × 10−14 s−1, λ = 1.2, and E
F = 0.2 eV, respectively.
The text was submitted by the authors in English. 相似文献
4.
利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献
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以LCD为目标的自动定焦判据选择 总被引:2,自引:0,他引:2
在光学综合自动测量中 ,使用液晶显示屏作为分划板可以大大简化结构 ,提高效率 ,真正地实现自动测量。由于液晶显示具有对比度低、噪声大等特点 ,所以根据液晶的这些特点以及图像处理和CCD信号接收的特点选择两种适用的判据进行了分析和试验比较 ,并给出了结果。结果表明 ,这两种判别函数都适用于以液晶显示屏为目标和用图像处理方法进行光学参数测量的系统 ,其中锐度判别函数更优于信息熵判别函数 ,前者具有更好的抗干扰性和稳定性 ,而且其判定结果更接近目视清晰度判别 相似文献
7.
MOHAMED SAÏDI 《Compositio Mathematica》1997,107(3):319-338
Let R be a discrete complete valuation ring, with algebraically closedresidue field. Let X be a semi-stable R-curve, with smooth generic fibre. In this paper we study tame coverings of X. 相似文献
8.
S. A. Sergeenkov V. V. Gridin M. Ausloos 《Zeitschrift für Physik B Condensed Matter》1996,101(4):565-571
The transport current density, flowing radially from the center of a superconducting disk to its perimeter, in a so-called Corbino geometry, results in a double action on the vortex motion when the applied magnetic field is perpendicular to the disk’s plane. First, the depinned vortices are set into a nearly circular motion in the plane of the disk. Second, the non-uniform current density profile activates the intrinsic weak links, resulting in a non negligible proximity dominated quasiparticle contribution. In turn, these intrinsic junctions impede the circular motion of vortices giving rise to a proximity influenced thermally activated flux creep. This provides a simple technique to deconvolute the flux motion and the quasiparticle induced components of the total dissipative resistivity broadening below T c . The case for a YBaCuO disk is hereby examined and measured in this context. It is shown that such a deconvolution can be made and theoretical laws for the field dependences are also obtained and confirm the data. Furthermore, the paraconductivity region just above T c (B) appears to be dominated by the macroscopic fluctuations accompanying the vortex core motion. 相似文献
9.
S. A. Sergeenkov 《JETP Letters》2002,75(7):317-321
Based upon the recently introduced thermophase and piezophase mesoscopic quantum effects in Josephson junctions, several novel phenomena in a twisted superconductor (containing a small annular SIS-type contact) under the influence of a thermal gradient and applied magnetic field are predicted. Namely, we consider a torsional analog of Josephson piezomagnetism (and related magnetomechanical effect), as well as the possible generation of a heat-flux-induced magnetic moment in a weakly coupled superconductor under torsional deformation (analog of Zavaritskii effect) along with the concomitant phenomena of piezothermopower and piezothermal conductivity. The conditions under which the predicted effects can be experimentally measured in conventional superconductors and nanostructure materials with implanted Josephson contacts are discussed. 相似文献
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