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1.
Banach空间上非Lipschitz映射的渐近行为   总被引:2,自引:0,他引:2  
设C是具Fréchet可微范数的一致凸Banach空间E的非空凸闭子集,G是定向集.{T:t∈G}是C上的渐近非扩张型映照.本文给出了{T:t∈G}的弱收敛定理.  相似文献   
2.
This paper is concerned with a system modeling a competitor–competitor–mutualist three-species Lotka–Volterra model. By Schauder fixed point theory, the existence of positive solutions to a strongly coupled elliptic system is given. Applying the method of upper and lower solutions and its associated monotone iterations, the true solutions are constructed and a numerical simulation is also presented. Our results show that this system possesses at least one coexistence state if cross-diffusions and cross-reactions are weak.  相似文献   
3.
设 R是 G-分次,本文讨论了环 R的相关环 R,R# G*, Re, Q(R), RG, R*G及 R的正规化扩张S的非奇异性,右一致性,右基座之间的关系.当R是YJ-内射模时,证明了J(R)=Z(R)。  相似文献   
4.
The present paper deals with the investigation of the interaction phenomena of regular waves with arrays of circular cylinders either bottom-mounted or floating in front of a vertical breakwater of infinite and finite length. The acting loads on the array have been modeled using an analytical solution to the diffraction problem. The method of images is applied to define the fluid flow around the bodies of the array in front of a breakwater of infinite length, whereas the finite-length breakwater is represented by an elliptical cylinder with zero semi–minor axis. The multiple scattering approach and the direct matrix inversion method are compared to describe the hydrodynamic interaction phenomena among the members of the array. Focus is placed on the so called “near trapped” mode phenomena, created by an array of finite length, associated to the presence of the breakwater supplemented by representative numerical results concerning the exciting loads on the cylindrical bodies.  相似文献   
5.
《Fluid Phase Equilibria》2005,231(2):221-230
Polymer cyclic olefin copolymer (COC) is produced from the reaction of attaching ethyl groups to the norbornene monomer in liquid phase. The first step of process is dissolving ethylene in a liquid phase where toluene is present as a cosolvent. Thus, the solubility of ethylene in liquid toluene is the most important factor affecting the production of COC. In this study, the solubility of ethylene in toluene was measured in the temperature range from 323.15 to 423.15 K and pressure range from 5 to 25 bar. The experiments were conducted by the method of pressure decaying with a newly designed apparatus. The experimental results show that the solubility of ethylene in toluene increases with increasing pressure but decreases with increasing temperature.The experimental solubility data were expressed in the vapor–liquid equilibrium relationship and correlated fairly well by the bubble–pressure calculation with the Peng–Robinson equation of state (PR EOS) incorporated with the van der Waals one-fluid and the Zhong–Masuoka mixing rules with the consideration of binary interaction parameters. The results showed the van der Waals (vdW-1) mixing rule is slightly better than the Z–M mixing rule for pressure correlation but the Z–M mixing rule is slightly better for vapor composition correlation.A semi-empirical solubility equation with four parameters for the present binary system was proposed in this study. This proposed model estimates the solubility easier and as accurate as the PR EOS does for the present system.  相似文献   
6.
In this paper we consider the system of reaction-diffusion-advection equations with a free boundary, which arises in a competition ecological model in heterogeneous environment. In strong competition case, we study the influence of competition rates on the long time behavior of solutions and prove that two species spatially segregate as the competition rates become large. Besides, by using a blow up method, we obtain the uniform Hölder bounds for solutions of the system.  相似文献   
7.
We have previously highlighted the ability of the N,N-bistrimethylsilylaminostannylene 1 to produce monoallylstannanes 2 in quantitative yields, starting from various functionalised allylic halides via an insertion reaction. In contrast with more electrophilic trihalogenotin radicals, the tin-centred radicals generated from reagents 2 are shown to be the best candidates towards allylic radical transfer, giving allylated products in similar yields as those obtained with classical tributyltin radicals.  相似文献   
8.
9.
We report on the formation and the low-temperature physical properties of a novel compound EuPdGe3 that crystallizes with the tetragonal BaNiSn3-type crystal structure. The material exhibits antiferromagnetic ordering below TN=12.4 K, as inferred from the magnetic susceptibility, heat capacity and electrical resistivity data. The compound shows good metallic conductivity.  相似文献   
10.
Triton X-100/n-C~4H~9OH/H~2O体系的扩散系数与结构特性   总被引:5,自引:0,他引:5  
郭荣  丁元华  刘天晴 《化学学报》1999,57(9):943-952
在无外加探针条件下用循环伏安法测定了不同形状TritonX-100胶束的扩散系数,得到第一cmc(临界胶束浓度)为3.1×10^-^4mol.L^-^1,第二cmc为1.3×10^-^3mol.L^-^1,并给出了TritonX-100的电化学反应机理。随正丁醇含量的增加,TritonX-100球形胶束的扩散系数迅速增加,正丁醇的增溶分数略有降低,但胶束内微极性却降低较多;棒状胶束转变为球形胶束,正丁醇的增溶分数基本不变,但胶束内微极性降低。随温度升高,TritonX-100分子与胶束的扩散系数均增加。正丁醇含量<1.5%时,扩散活化能E~D随正丁醇含量增加而迅速增加;但正丁醇含量>1.5%时,E~D增加变缓。  相似文献   
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