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971.
Tessellations of that use convex polyhedral cells to fill the space can be extremely complicated, especially if they are not “facet‐to‐facet”, that is, if the facets of a cell do not necessarily coincide with the facets of that cell's neighbours. In a recent paper 15 , we have developed a theory which covers these complicated cases, at least with respect to their combinatorial topology. The theory required seven parameters, three of which suffice for facet‐to‐facet cases; the remaining four parameters are needed for the awkward adjacency concepts that arise in the general case. This current paper establishes constraints that apply to these seven parameters and so defines a permissible region within their seven‐dimensional space, a region which we discover is not bounded. Our constraints in the relatively simple facet‐to‐facet case are also new. 相似文献
972.
Nirmal Kumar Sarkar Joydeep ChoudhurySrinivasa Rao Karumuri Ramendu Bhattacharjee 《Vibrational Spectroscopy》2011,56(1):99-104
Using the U(4) algebraic model, in this work we report a study of the vibrational spectra of SO2, H2018 and D2O16. The inclusion of intermode couplings in algebraic models has been stated to give a deep insight into detailed spectroscopy for these bent XY2 molecules. Improved set of algebraic parameters has been reported to provide improved RMS deviations for these molecules. 相似文献
973.
在氧化铟锡( ITO)导电玻璃表面电泳沉积制备ZnO-C60和ZnO-MWCNT复合涂层电极,经后续热处理增强其结合强度,通过SEM观察2种电极复合涂层的表面形貌,并使用CHI 705电化学分析仪和PMI-E电致化学发光系统测定其光电性质.结果表明,ZnO-C60复合涂层电极具有较高的稳定性,在可见光辐照下,该电极显示... 相似文献
974.
以水溶性C60和TiO2粒子为前驱体,采用水热法制备了载有C60的锐钛矿型TiO2纳米粒子。应用X射线衍射、透射电子显微镜、红外光谱、紫外-可见漫反射光谱、荧光光谱对产物进行了表征。以对-硝基苯酚为模型污染物研究了产物的光催化活性,结果表明适量负载C60可以提高TiO2纳米粒子的光催化活性,C60起着传输电子、促进TiO2光生载流子分离的作用,且经7次循环使用后对-硝基苯酚的降解效率仍能达到74%。讨论了载有C60的TiO2纳米粒子光催化降解对-硝基苯酚的机理。 相似文献
975.
F. Charro 《Journal of Differential Equations》2011,251(6):1562-1579
In this paper we study the monotonicity of positive (or non-negative) viscosity solutions to uniformly elliptic equations F(∇u,D2u)=f(u) in the half plane, where f is locally Lipschitz continuous (with f(0)?0) and zero Dirichlet boundary conditions are imposed. The result is obtained without assuming the u or |∇u| are bounded. 相似文献
976.
In this paper, we first provide some sufficient conditions for the existence of global compact random attractors for general random dynamical systems in weighted space (p?1) of infinite sequences. Then we consider the existence of global compact random attractors in weighted space for stochastic lattice dynamical systems with random coupled coefficients and multiplicative/additive white noises. Our results recover many existing ones on the existence of global random attractors for stochastic lattice dynamical systems with multiplicative/additive white noises in regular l2 space of infinite sequences. 相似文献
977.
Augusto Visintin 《Journal of Differential Equations》2011,250(3):1521-1552
This work deals with the homogenization of hysteresis-free processes in ferromagnetic composites. A degenerate, quasilinear, parabolic equation is derived by coupling the Maxwell-Ohm system without displacement current with a nonlinear constitutive law:
978.
979.
The aim of this paper is to study the qualitative behavior of large solutions to the following problem
980.
In this paper we study the maximal operators and the convolution operators Tδ associated with multipliers of the form