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101.
Michael Taylor 《Journal of Fourier Analysis and Applications》1999,5(5):449-463
We prove a number of results about pointwise convergence of eigenfunction expansions of functions on compact manifolds. In particular, we establish that the Pinsky phenomenon holds for piecewise smooth functions on the three-dimensional torus, with jump across the boundary of a ball, in the same form as it was discovered for functions on three-dimensional Euclidean space. Our work on this has been stimulated by recent work of Brandolini and Colzani, and we also discuss some variants of their results. 相似文献
102.
在晶格气体模型的框架中研究了129Xe系统在破裂过程中的热力学性质和轻粒子发射性质随核温度和系统的冻结密度的变化规律.计算发现在不同的冻结密度下,129Xe破裂过程的物理观测量呈现了不同的温度相关性.在这种情况下,核物质液气相变发生时的临界温度强烈地依赖于系统的冻结密度.当激发能代替温度作为一个自变量时,临界激发能将不再灵敏地依赖于系统的冻结密度.除此之外,由于不同冻结密度而引起的不同粒子发射产额的温度相关性,也随着激发能的应用,出现了几乎一致的激发能依赖性.从这些结果中可以认为,激发能可以作为一个控制核破裂的基本物理量和标度量. 相似文献
103.
从物理化学的角度分析了日常生活中的返潮现象,以风冷冷冻除湿机、空调、转轮除湿机为例,解析了室内除湿中蕴含的物理化学原理。引导学生利用物理化学的眼光看待生活,有利于学生分析生活现象的本质,提高逻辑分析能力,克服学习物理化学畏难情绪的同时增加学习兴趣。 相似文献
104.
The two-dimensional dilute granular flow on a smooth incline bounded by rough sidewalls is investigated experimentally, and
the transverse density profiles of granular flux (ζ = ρ v) across the channel are measured. The results show that the transverse density profiles of granular flux are symmetric about
the channel center and that the density of granular flux near the boundary is clearly lower than that of the center. There
is a critical width of channel W
c for the transition of the density of granular flux. The density of granular flux near the boundary decays with the increasing
of inclination (sinθ) of the channel.
Supported by the National Natural Science Foundation of China (Grant No. 10274071) and the Department of Education of Zhejiang
Province (Grant Nos. 20050916 and y200804093) 相似文献
105.
姜玲玉 《纯粹数学与应用数学》2013,(5):458-464
研究广义可压缩弹性杆方程解的爆破条件及尖峰孤立波解的存在性.首先利用所建立的爆破准则,给出一个方程在有限时刻爆破的充分条件.其次,严格证明了其尖峰孤立波解的整体存在性.该结果丰富了此类Camassa-Holm型方程的研究. 相似文献
106.
Hao-Miao Zhou You-He Zhou Xiao-Jing Zheng Qiang Ye 《Journal of magnetism and magnetic materials》2009,321(4):281-290
In this paper, a new general nonlinear magnetostrictive constitutive model is proposed for soft ferromagnetic materials, and it can predict magnetostrictive strain and magnetization curves under various pre-stresses. From the viewpoint of magnetic domain, it is based on the important physical fact that a nonlinear part of the elastic strain produced by magnetic domain wall motion under a pre-stress is responsible for the change of the maximum magnetostrictive strain in accordance with the pre-stress. Then the reduction of magnetostrictive strain from the maximum is caused by the domain rotation. Meanwhile, the magnetization under various pre-stresses in this model is introduced by magnetostrictive effect under the same pre-stress. A simplified 3-D model is put forward by means of linearizing the nonlinear function, i.e. the nonlinear part of the elastic strain produced by domain wall motion, and by using the quartic of magnetization to describe domain rotation. Besides, for the convenience of engineering applications, two-dimensional (plate or film) and one-dimensional (rod) models are also given for isotropic materials and their application ranges are discussed too. In comparison with the experimental data of Kuruzar and Jiles, it is found that this model can predict magnetostrictive strain and magnetization curves under various pre-stresses. The numerical simulation further illustrates that the new model can effectively describe the effects of the pre-stress or residual stress on the magnetization and magnetostrictive strain curves. Additionally, this model can be degenerated to the existing magnetostrictive constitutive model for giant magnetostrictive materials (GMM), i.e. a special soft ferromagnetic material. 相似文献
107.
108.
The conductivity behavior of Al(OH)3-acrylamide hybrid polyacrylamide (hybrid PAAm) in distilled water was studied. A discontinuity phenomenon of the conductivity (k) versus concentration (c) curve of the hybrid PAAm in a certain concentration regime is found. This phenomenon is dependent on the molecular weight of the hybrid PAAm and on the particle size and content of the Al(OH)3 colloid in the hybrid PAAm. This phenomenon was accounted for assuming ionization of the hybrid PAAm. 相似文献
109.
110.