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排序方式: 共有378条查询结果,搜索用时 15 毫秒
91.
In this article, the spatial behaviour of a class of nonlinear viscoelasticity equations is studied. We obtained some alternative results for the solutions under suitable conditions on the nonlinear terms. The main tool used is the weighted energy method. Our results can be viewed as a version of Saint-Venant's principle to the viscoelasticity equations. 相似文献
92.
In this paper, we derive a time-periodic lattice model for a single species in a patchy environment, which has age structure and an infinite number of patches connected locally by diffusion. By appealing to the theory of asymptotic speed of propagation and monotonic periodic semiflows for travelling waves, we establish the existence of periodic travelling wave and spreading speed of the model. 相似文献
93.
94.
本文主要考虑在外区域上的一类半线性伪抛物型方程的解的长时间行为.本文得到的临界指标揭示了边界上的非齐次条件将对解的长时间行为产生本质影响. 相似文献
95.
热处理碳纸电极上VO2+/VO+2氧化还原动力学 总被引:1,自引:0,他引:1
在不同温度下热氧化处理碳纸, 用循环伏安、极化曲线和交流阻抗方法研究碳纸电极上VO2+/VO+2氧化还原动力学. 循环伏安和极化曲线结果表明, 随着热处理温度的升高, VO2+/VO+2氧化还原反应的速率常数及交换电流增大. 建立了VO2+/VO+2氧化还原反应的交流阻抗等效电路模型. 拟合结果表明, 热处理增大了碳纸电极表面的双电层电容, 减小了VO2+/VO+2氧化还原反应的电荷转移电阻. 用循环伏安和交流阻抗两种方法求得的VO2+和VO+2的扩散系数基本相同, 表明所构建的交流阻抗等效电路模型与电极反应过程相符合. 相似文献
96.
Jing Li Jingxue Yin Chunhua Jin 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2010,61(5):835-847
This paper is concerned with the existence of nonnegative continuous solutions for the Cauchy problem of a class of fully nonlinear degenerate parabolic equations. 相似文献
97.
The absorption of free alkali at low concentration by subacid resin was traced with electric conductance method,the effect of temperature on the adsorption,the activation energy of adsorption (Ea) and interaction energy(U) was studied.The result showed that,the process of low concentration alkali adsorption by subacid resin was in accordance with mechanism of monomolecular layer absorption,in addition,with the increasing of temperature,the interaction energy between adsorbate and sorbent increase,so did the surface adsorption rate(k),and linear correlation existed between interaction energy(U) and temperature(T). 相似文献
98.
In the present work, the porous structure of fly ash/phosphate geopolymer hollow sphere structures (FPGHSS), prepared by pre-bonding and curing technology, has been characterized by multi-resolution methods from sub-millimeter to nano-scale. Micro-CT and confocal microscopy could provide the macroscopic distribution of porous structure on sub-millimeter scale, and hollow fly ashes with sphere shape and several sub-millimeter open cells with irregular shape were identified. SEM is more suitable to illustrate the distribution of micro-sized open and closed cells, and it was found that the open cells of FPGHSS were mainly formed in the interstitial porosity between fly ashes. Mercury porosimeter measurement showed that the micro-sized open cell of FPGHSS demonstrated a normal/bimodal distribution, and the peaks of pore size distribution were mainly around 100 and 10 μm. TEM observation revealed that the phosphate geopolymer was mainly composed of the porous area with nano-pores and dense areas, which were amorphous Al–O–P phase and α-Al2O3 respectively. The pore size of nano-pores demonstrated a quasi-normal distribution from about 10 to 100 nm. Therefore, detailed information of the porous structure of FPGHSS could be revealed using multiple methods. 相似文献
99.
基于腕部手厥阴心包经循行区域的解剖结构,建立了腕部手厥阴心包经和旁开非经络线区域组织光传输结构的简化模型,并利用蒙特卡罗模拟的方法分别模拟了光在腕部手厥阴心包经、相邻肌腱以及旁开非经络线上的光传输特性。模拟结果表明,光沿腕部手厥阴心包经呈优势传输,与本实验室之前实验所得的结果相一致。分别计算了三个模型中各层的光通量情况,计算结果表明,腕部心包经循行区域的光传输特性主要受该区域的底层结构和底层组织成分影响,光在底层结构中也是沿腕部心包经呈优势传输的,并且该优势传输的现象与腕部心包经底层的筋膜间隙结构有关。 相似文献
100.
We address multipole surface solitons occurring at the interface between a linear medium and a nonlocal nonlinear medium. We show the impact of nonlocality, the propagation constant, and the linear index difference of two media on the properties of the surface solitons. We find that there exist a threshold value of the degree of the nonlocality at the same linear index difference of two media, only when the degree of the nonlocality goes beyond the value, the multipole surface solitons can be stable. 相似文献