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111.
聚丙烯酸高碳醇酯(PBA)及聚丙烯酸十八醇酯(POA)是具有长烷基侧链的梳状聚合物,在溶剂苯中的Huggins常数(k′)随其分子量(M)的变化而变化.在PBA-苯体系中发现,当M低于某一临界分子量(MLC)时,k′随分子量的降低显著增大;当M大于某临界分子量(MHC)时,k′随分子量的升高而增大;当M在MLC~MHC时,k′基本上保持不变.而在POA-苯体系中发现,当M低于某一临界分子量(MC)时,k′随分子量的降低显著增大;当M大于该临界分子量(MC)时,k′在0.33~0.43变化.文中同时给出了精确算法用来计算PBA-苯体系及POA-苯体系中PBA及POA的特性粘度.当k′>0.758时,用稀释外推法计算;当0.758>k′>0.426时,用一点法公式[η]=ηsp/C(√)ηr计算;当0.426>k′>0.334时,用另一一点法公式[η]=(√)2(ηsp-lnηr)/C计算. 相似文献
112.
113.
采用基于相对论平均场的耦合常数解析延拓方法研究球形核的单粒子共振态.具体计算了Zr同位素链中巨晕核的核芯核122Zr阈值附近的中子共振态的能量、宽度和波函数,其结果同相应的散射相移法的结果一致. Using analytic continuation in the coupling constant (ACCC) method within the framework of the self-consistent relativistic mean field (RMF) theory, the energies, widths and wave functions for single-particle resonant states close to the continuum threshold are evaluated. Predictions are also compared with corresponding results obtained by the scattering phase shift method. 相似文献
114.
115.
The enthalpies and free energies of proton affinity (PA) were calculated by the PM3 method for 27 thiophenoxide anions. For thiophenols, linear correlation has been found between the PAs and the values of pK
a
measured by different authors in aqueous acetone, aqueous ethanol, and methanol media. The dependences found permit one to predict a priori the protolytic properties of thiophenols. The differential effects of aqueous ethanol media with different ethanol contents on thiophenol acidity were evaluated based on quantum-chemical data.Original Russian Text Copyright © 2004 by A. N. Pankratov and A. V. Shalabai__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 800–806, September–October, 2004. 相似文献
116.
Possible triggering of solar activity to big earthquakes (Ms ≥ 8) in faults with near west-east strike in China 总被引:1,自引:0,他引:1
HAN Yanben GUO Zengjian WU Jinbing & MA Lihua . National Astronomical Observatories Chinese Academy of Sciences Beijing China . Earthquake Research Institute of Lanzhou CSB Lanzhou China Correspondence should be addressed to Han Yanben 《中国科学G辑(英文版)》2004,(2)
A big earthquake (Ms = 8.1) occurred at western Kunlun Mts gap on November 14, 2001. It is the biggest earthquake in China in the past 50 years and the only one with a magnitude bigger than 8 in China after Dangxiong Earthquake (M = 8) in Tibet in 1951. The big earthquake has drawn wide attention of scientists in seismological, geophysical, geological and astro-geodynamic circles. Scientists are interested in the occurrence regularity of the very big earthquakes and try to find out the fac… 相似文献
117.
P. Cicman M. Francis J.D. Skalny S. Matejcik T.D. Märk 《Czechoslovak Journal of Physics》2003,53(3):181-190
The rate constant for dissociative electron attachment to ozone has been derived over the energy range from about 0 to 10 eV using recently measured and also corrected cross section data. The new rate constant data sets for two partial dissociative channels, as well as for the total dissociative electron attachment, are compared with previously reported values, and existing discrepancies are discussed. 相似文献
118.
Using the linearization of Einstein's equations for weak gravitational fields, a specific model of gravito-magnetofluid is elaborated. The study of wave formation and propagation in such a medium is necessarily connected to the existence of the cosmological constant. 相似文献
119.
Constants of Motion for Several One-Dimensional Systems and Problems Associated with Getting Their Hamiltonians 总被引:1,自引:1,他引:0
G. López L. A. Barrera Y. Garibo H. Hernández J. C. Salazar C. A. Vargas 《International Journal of Theoretical Physics》2004,43(10):2009-2021
The constants of motion of the following systems are deduced: a relativistic particle with linear dissipation; a no-relativistic particle with a time explicitly depending force; a no-relativistic particle with a constant force and time depending mass; and a relativistic particle under a conservative force with position depending mass. The Hamiltonian for these systems, which is determined by getting the velocity as a function of position and generalized linear momentum, can be found explicitly at first approximation for the first system. The Hamiltonians for the other systems are kept implicitly in their expressions for their constants of motion. 相似文献
120.