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941.
Hexiang Yan Guohua Tian Kang Sun Yong Zhang Yinxi Zhang 《Journal of Polymer Science.Polymer Physics》2005,43(5):573-584
The effects of filler loading and a new silane coupling agent 3‐octanoylthio‐1‐ propyltriethoxysilane (NXT silane) on the polymer‐filler interaction and mechanical properties of silica‐filled and carbon black‐filled natural rubber (NR) compounds were studied. Silica (high dispersion silica7000GR, VN2, and VN3) and carbon black (N330) were used as the fillers, and the loading range was from 0 to 50 phr. The loading of NXT silane was from 0 to 6 phr. Experimental results show that the maximum and minimum torques of silica and carbon black‐filled NR increase with increasing filler loading. With increasing filler loading, the scorch time and optimum cure time decrease for carbon black‐filled NR, but increase for silica‐filled NR. The minimum torque, scorch time, and optimum cure time decrease because of the presence of NXT silane. For the carbon black and silica‐filled NR, the tensile strength and elongation at break have maximum values, but the hardness, M300, M100, and tear strength keep increasing with filler loading. The mechanical properties of silica‐filled NR were improved in the presence of NXT silane. With increasing filler loading, the storage modulus of filled NR increases, but the loss factor decreases. Carbon black shows the strongest polymer‐filler interaction, followed by VN3, 7000GR, and VN2. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 573–584, 2005 相似文献
942.
943.
The characteristics of harmonic radiation due to electron oscillation driven by an intense femtosecond laser pulse are analyzed considering a single electron model. An interesting modulated structure of the spectrum is observed and analyzed for different polarization. Higher order harmonic radiations are possible for a sufficiently intense driving laser pulse. We have shown that for a realistic pulsed photon beam, the spectrum of the radiation is red shifted as well as broadened because of changes in the longitudinal velocity of the electrons during the laser pulse. These effects are more pronounced at higher laser intensities giving rise to higher order harmonics that eventually leads to a continuous spectrum. Numerical simulations have further shown that by increasing the laser pulse width broadening of the high harmonic radiations can be limited. 相似文献
944.
Tao Xu Chun-Yi Zhang Guang-Mei Wei Juan Li Xiang-Hua Meng Bo Tian 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,55(3):323-332
Currently, the variable-coefficient nonlinear Schr?dinger
(NLS)-typed models have attracted considerable attention in such
fields as plasma physics, nonlinear optics, arterial mechanics and
Bose-Einstein condensates. Motivated by the recent work of Tian et
al. [Eur. Phys. J. B 47, 329 (2005)], this paper is devoted to
finding all the cases for a more generalized NLS equation with
time- and space-dependent coefficients to be mapped onto the
standard one. With the computerized symbolic computation, three
transformations and relevant constraint conditions on the
coefficient functions are obtained, which turn out to be more
general than those previously published in the literature. Via
these transformations, the Lax pairs are also derived under the
corresponding conditions. For physical applications, our
transformations provide the feasibility for more
currently-important inhomogeneous NLS models to be transformed
into the homogeneous one. Applications of those transformations to
several example models are illustrated and some soliton-like
solutions are also graphically discussed. 相似文献
945.
该文介绍一类岩性反演问题.从理论上分析LMS估计的结构。在空间齐次假设下,得到不变矩阵α=(αij)的递推计算关系.同时,建立一种计算机模拟岩性的算法,该算法被实践证明是有效的. 相似文献
946.
The protected aglycone of saponin OSW-1, a new antitumor natural product, was synthesized in 13 linear steps in 9.5% overall yield by utilizing the intact skeleton of diosgenin. This strategy demonstrated a higher efficiency than the routine synthesis of steroids with side chains. 相似文献
947.
Daiqi Ye Mingli Fu Liuqing Tian Hong Liang Tiezhi Rong Shengzhong Cheng Xianshen Pang 《Research on Chemical Intermediates》2003,29(3):271-284
A series of vanadyl pyrophosphate (VPO) modified by several additives has been investigated with the aim to reveal the promotion mechanism of the additives for selective conversion of n-butane to maleic anhydride (MA). Catalyst performance and various physicochemical characterization including XPS, XRD, FT-IR, DTA and BET indicated that the properties of additives, such as electronegativity and ion radius, contributed much to the effect of the additives on the structure and surface characteristics of VPO catalysts, and then influenced the catalytic behavior. The remarkable effects of additives on the surface vanadium and oxygen species were discussed. It was shown that maximum MA selectivity could be found with a moderate V5+ /V4+ ratio, and the catalytic activity and selectivity were improved, respectively, with the increase of surface active oxygen species, as well as as their amount and stability. 相似文献
948.
利用多模压缩态理论,研究了由多模复共轭相干态|{Zj*}〉q(j =1,2,3,…,…,q)、多模复共轭相干态的相反态|{-Zj*}〉q和多模虚相干态|{iZj}〉q的线性叠加所组成的第Ⅴ类三态叠加多模叠加态光场|ψ5(3)〉q中广义电场分量的等幂次N次方Y压缩特性 .结果发现 :当压缩次数N=2 p且p=2m+1(m=0,1,2,…,…)时,在一定的条件下,态|ψ5(3)〉q的广义电场分量(即第二正交相位分量)可呈现出周期性变化的、偶数次的等幂次2(2m+1)次方Y压缩效应 . 相似文献
949.
950.
In this paper, we show several arithmetic properties on the residues of binomial coefficients and their products modulo prime
powers, e.g.,
for any distinct odd primes p and q. Meanwhile, we discuss the connections with the prime recognitions.
Received November 5, 1998, Accepted December 7, 2000. 相似文献