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141.
非线性伪抛物方程由于其来源于一些重要的物理过程而成为研究热点.对于一类三阶非线性伪抛物方程的初边值问题,给出了Hilbert空间中相应的强制不等式,利用同胚理论及推广的反函数定理,得到了非线性方程初边值问题解的大范围存在定理.对于相应的半线性方程给出了初边值问题解的大范围存在性、唯一性定理. 相似文献
142.
Summary
K-absorption edge shifts of the absorbing atom in its complexes have been correlated with the effective nuclear charge on the
central metal ion, overall electronegativity difference between the nearest neighbours in the complexes and the ionic radius
of the central metal ion; a linear correlation has been observed among them, the data subjected to the method of least squares
indicated that the correlation is genuine.
Riassunto Gli slittamenti dell’orlo di assorbimentoK dell’atomo assorbente nei suoi complessi sono stati correlati con la carica nucleare efficacie sullo ione metallico centrale, con la differenza di elettronegatività generale tra vicini prossimi nei complessi e col raggio ionico dello ione metallico centrale; una correlazione lineare è stata osservata tra loro, i dati soggetti al metodo dei minimi quadranti hanno indicato che la correlazione è genuina.相似文献
143.
Xie Xiangdong 《Annals of Differential Equations》2005,21(3):474-479
A class of cubic system, which is an accompany system of a quadratic differential one, is studied. It is proved that the system has at most one limit cycle, and the critical point at infinity is a higher order one. The structure and algebraic character of the critical point at infinity are obtained. 相似文献
144.
145.
Anna de Mier 《Discrete Mathematics》2005,301(1):57-65
We prove that if a graph H has the same Tutte polynomial as the line graph of a d-regular, d-edge-connected graph, then H is the line graph of a d-regular graph. Using this result, we prove that the line graph of a regular complete t-partite graph is uniquely determined by its Tutte polynomial. We prove the same result for the line graph of any complete bipartite graph. 相似文献
146.
A. I. Gerasimov V. N. Razzhevaikin 《Computational Mathematics and Mathematical Physics》2008,48(8):1406-1417
Mathematical parasite-host models are generalized to the case when the population members differ in susceptibility and contagiousness, there is an external source of infection, and the model parameters depend periodically (seasonally) on time. The model is proved to have a periodic solution that is unique and exponentially stable for sufficiently small periodic oscillations of the coefficients. 相似文献
147.
Jong Uhn Kim 《Transactions of the American Mathematical Society》2008,360(2):575-607
We prove the existence and uniqueness of solutions to the initial boundary value problem for a one-dimensional wave equation with unilateral boundary conditions and random noise. We also establish the existence of an invariant measure.
148.
The fluorescent spectrum and the excitation spectrum were used to present the cluster molecular structure feature in ethanol-water solutions.Through analyzing the fluorescent characteristics of an excimer,it is proposed that the excimers are formed between the ethanol-water cluster molecules in the excited state and in the ground state.The fluorescent lifetime and the fluorescent intensity decay process give information about the photo-physical and photo-chemical processes of the formation and the dissociation of an excimer.The theoretical calculation and physical analysis coincide with the experimental results.The preliminary conclusion about the structure feature of ethanol-water cluster molecule is that it has a planar one like a sandwich. 相似文献
149.
In this paper,we consider nonnegative solutions to Cauchy problem for the general nonlinear filtration equations ut-Dj(aij(x,t,u)Diφ(u))+bi(t,u)Diu+C(x,t,u)=0,and obtain the existence,uniqueness and blow-up in finite time of these solutions under some structure conditions. 相似文献
150.