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891.
892.
The length-distribution of stereoregular sequences in low-density polyethylene (LDPE) is determined by a computer-aided analysis of cp-melting curves within the framework of thermodynamics of eutectoid copolymers. Small-angle x-ray scattering patterns are then described by using the structure data derived. One of the results is that fluctuations of the mean electron-density are increasingly reduced with an increasing degree of crystallinity.Dedicated to Prof. Dr. W. Pechhold on the occasion of his 60th birthday 相似文献
893.
M.S. Anagnostou I. Panagiotopoulos A. Kostikas D. Niarchos G. Zouganelis 《Journal of magnetism and magnetic materials》1994,130(1-3):57-62
From the analysis of Mössbauer data for Y2Fe17 and Y2Fe17N3−δ at various temperatures the hyperfine fields for 4f, 6g, 12j, 12k iron sites were estimated as a function of temperature. The reduced magnetizations calculated from the values of the hyperfine fields are fitted with a mean field model for four interacting sublattices using a computer program. The estimated exchange interaction from the fitting procedure between the 4f sites is found strongly negative (antiferromagnetic) in Y2Fe17 whereas in Y2Fe17N3−δ it increases and becomes weak negative following a modified Slater-Néel curve. The rest of the exchange interactions are found positive or weak negative depending on the distances between the Fe atoms. 相似文献
894.
We consider a spatially distributed hybrid system consisting of a convection/reaction system in which the reaction switches discontinuously in time between modes, independently at each spatial point on reaching “switching thresholds”. The model involves a novel formulation for evolution of the free boundary between the modal regions. 相似文献
895.
896.
897.
P. V. Pavlov I. V. Babushkin N. A. Loiko N. N. Rosanov S. V. Fedorov 《Radiophysics and Quantum Electronics》2004,47(10-11):898-904
We consider spatial dissipative solitons arising in the system of two nonlinear thin films which interact resonantly with light. Symmetric and nonsymmetric solitons and methods of their exciting and switching are studied. 相似文献
898.
899.
E. I. Gordon 《Siberian Mathematical Journal》1991,32(2):197-209
Gor'kii. Translated fromSibirskii Matematicheskii Zhurnal, Vol. 32, No. 2, pp. 26–40, March–April 1991. 相似文献
900.
Convergence properties of weighted sums of functions in D([0, 1]; E) (E a Banach space) are investigated. We show that convergence in the Skorokhod J1-topology of a sequence (xn) in D([0, 1]; E) does not imply convergence of a sequence (
n) of averages. Convergence in the J1-topology of a sequence (
n) of averages is shown, under the growth condition xn ∞ = o(n), to be equivalent to the convergence of (
n) in the uniform topology. Convergence of a sequence (xn,) is shown to imply convergence of the sequence (
n) of averages in the M1 and M2 topologies. The strong law of large numbers in D[0, 1] is considered and an example is constructed to show that different definitions of the strong law of large numbers are nonequivalent. 相似文献