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161.
162.
清末诗歌中蕴含着丰富的反缠足内容,就其缘由而言,主要包含以下几个方面:其一,缠足使女子受极刑;其二,阻碍女学的发展;其三,致使家庭贫穷;其四,造成种族贫弱。同时,也还有其他方面的一些原因,如缠足与传统的儒家伦理观念不符,遇到火险兵祸之类的紧急状况时小脚不利于逃生,西方传教士的宣传等。诗歌中的反缠足内容乃是反缠足运动的具体体现,故而"以诗证史"是很好地解读手段。反缠足诗与放足运动紧密联系、相互影响,共同促进了女性解放运动的发展。  相似文献   
163.
《偏微分方程通讯》2013,38(1-2):133-155
Abstract

For regularized hard potentials cross sections, the solution of the spatially homogeneous Boltzmann equation without angular cutoff lies in Schwartz's space 𝒮(? N ) for all (strictly positive) time. The proof is presented in full detail for the two-dimensional case, and for a moderate singularity of the cross section. Then we present those parts of the proof for the general case, where the dimension, or the strength of the singularity play an essential role.  相似文献   
164.
Aqueous standard potentials, referred to that of the SHE as zero, were recently shown to vary linearly with gaseous ionization potentials, with the absolute potential of SHE as the intercept. This enabled arriving at the absolute redox potentials of elements. Here, the distances between the oxidized and reduced forms in aqueous solutions have been evaluated. From the linear dependence of these distances on the covalent radii of atoms, the radii of the redox components have been obtained. The latter also vary linearly with the aqueous ionic radii estimated earlier from ion‐water distances, and indicate the presence of aqueous molecular anions.  相似文献   
165.
讨论了在超对称性量子力学中的平移形不变性和尺度(scaling)形不变性之间的关系,得到更加广义的形不变性。  相似文献   
166.
O Akinlade  U Marte  L A Hussain 《Pramana》1990,34(4):289-295
The computed values of the temperature dependent electrical resistivity is presented for the alkaline earth metals Ca, Sr and Ba. Numerical values of the mean free paths obtained using a finite mean free path approach is also reported. The structure factor has been evaluated using experimental values for the phonon spectra while local model potentials were used for the form factors. Our numerical results compare favourably with experiments.  相似文献   
167.
We apply methods of quantum mechanics to mathematical modelling of price dynamics in a financial market. We propose to describe behavioral financial factors (e.g., expectations of traders) by using the pilot wave (Bohmian) model of quantum mechanics. Our model is a quantum-like model of the financial market, cf. with works of W. Segal, I.E. Segal, E. Haven. In this paper we study the problem of smoothness of price-trajectories in the Bohmian financial model. We show that even the smooth evolution of the financial pilot wave ψ(t,x) (representing expectations of traders) can induce jumps of prices of shares.  相似文献   
168.
Vinyl‐type copolymerization of norbornene (NBE) and 5‐NBE‐2‐yl‐acetate (NBE‐OCOMe) in toluene were investigated using a novel homogeneous catalyst system based on bis(β‐ketonaphthylamino)Ni(II)/B(C6F5)3/AlEt3. The copolymerization behavior as well as the copolymerization conditions, such as the levels of B(C6F5)3 and AlEt3, temperature, and monomer feed ratios, which influence on the copolymerization were examined. Without combination of AlEt3, the catalytic bis(β‐ketonaphthylamino)Ni(II)/B(C6F5)3 exhibited very high catalyst activity for polymerization of NBE. Combination of AlEt3 in catalyst system resulted in low conversion for polymerization of NBE. For copolymerization of NBE and NBE‐OCOMe, involvement of AlEt3 in catalyst is necessary. Slight addition of NBE‐OCOMe in copolymerization of NBE and NBE‐OCOMe gives rise to significant increase of catalyst activity for catalytic system bis(β‐ketonaphthylamino)Ni(II)/B(C6F5)3/AlEt3. Nevertheless, excess increase of the NBE‐OCOMe content in the comonomer feed ratios results in decrease of conversion as well as activity of catalyst. The achieved copolymers were confirmed to be vinyl‐addition copolymers through the analysis of FTIR, 1H NMR, and 13C NMR spectra. 13C NMR studies further revealed the composition of the copolymer and the incorporation rate was 7.6–54.1 mol % ester units at a content of 30–90 mol % of the NBE‐OCOMe in the monomer feeds ratios. TGA analysis results showed that the copolymer exhibited good thermal stability (Td > 410 °C) and failed to observe the glass transitions temperature over 300 °C. The copolymers are confirmed to be noncrystalline by WAXD analysis results and show good solubility in common organic solvents. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3990–4000, 2009  相似文献   
169.
Optimal Control of the Obstacle for an Elliptic Variational Inequality   总被引:3,自引:0,他引:3  
An optimal control problem for an elliptic obstacle variational inequality is considered. The obstacle is taken to be the control and the solution to the obstacle problem is taken to be the state. The goal is to find the optimal obstacle from H 1 0 (Ω) so that the state is close to the desired profile while the H 1 (Ω) norm of the obstacle is not too large. Existence, uniqueness, and regularity as well as some characterizations of the optimal pairs are established. Accepted 11 September 1996  相似文献   
170.
We study the asymptotic behavior of the free energy for a model (defined by Sinai) of one-dimensional random walk with random potential. In particular, we obtain a central limit theorem and a strong law of large numbers for this free energy. We use some results on the free energy to study some sample path properties of this random walk which are related respectively to its recurrence and localization. Some exponents describing the recurrence and localization are found.  相似文献   
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