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861.
862.
E.P. Yelsukov Yu.N. Vorobyov T.I. Arbusova I.B. Smolyak 《Journal of magnetism and magnetic materials》1994,130(1-3):44-50
We have measured the concentration dependence of the average magnetic moment per Fe atom
Fe(x) in microcrystalline and amorphous Fe-P alloys obtained over a wide concentration range using electrochemical deposition. The model of local magnetic moments has been used to described
Fe(x). On the basis of this model the effects of phosphorus on the value
Fe are explained in terms of the parameters of the local environment of the Fe atom. 相似文献
863.
Fe2+/Fe3+ ratio versus sediment depth values have been determined for ten lakes in British Columbia. The values often reflect the local topography of the lakes, the weathering history of the deposited minerals, and the diagenesis of the minerals after deposition in the lake. 相似文献
864.
S. A. Chernyak O. V. Shekhter N. L. Sergovskaya Yu. S. Tsizin 《Chemistry of Heterocyclic Compounds》1992,28(7):832-834
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 994–996, July, 1992. 相似文献
865.
866.
867.
We investigate the properties of maximum likelihood estimators in observation schemes of random variables that arrive at random time moments on a Poisson trajectory defined on some ergodic process.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 59, pp. 98–105, 1986. 相似文献
868.
G. V. Golubev 《Journal of Mathematical Sciences》1992,58(1):69-72
We consider nonlinear seepage with an initial pressure gradient in a region without stagnant zones. An algorithm based on the method of integral relationships is proposed for the determination of an auxiliary function defined as the square root of the permeability coefficient of the layer. The advantage of this method is that it reduces the problem to a form which can be solved by standard computer subprograms. Applications of the proposed approach are described.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 55, pp. 87–92, 1985. 相似文献
869.
On the basis of an effective potential for quarks and gluons, for models with fourfermion interaction, stability is examined both with and without vector fields (gluons). The stability conditions relate the main characteristics of four-quark models with quark and gluon condensates.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 189, pp. 3–9, 1991. 相似文献
870.
J. P. S. Farinha J. M. G. Martinho H. Xu M. A. Winnik R. P. Quirk 《Journal of Polymer Science.Polymer Physics》1994,32(9):1635-1642
Cyclization of a polystyrene chain (Mn = 10,600; Mw/Mn = 1.09) both ends labeled with 4-(1-pyrenyl)butanoamide groups was studied in cyclohexane between 25 and 95°C. The amide groups (peptide bonds) at both ends can form an intrachain hydrogen bond between the amide hydrogen at one chain end and the carbonyl oxygen at the other. The presence of two sets of conformers, random coils, and chains cyclized through hydrogen bonding, complicates the data analysis. The pyrene excimer kinetics of this polymer is well described by a model composed of two monomers (hydrogen bonded and nonbonded chains) and one excimer, in equilibrium. The cyclization rate constant for hydrogen-bonded chains is larger than the one for nonhydrogen-bonded chains. The pyrene excimer binding energy (ca. 1.6 kcal/mol) is lower than the published value for nonhydrogen-bonded chains (~ 9 kcal/mol), suggesting that intrachain hydrogen bonding hinders the stabilization of the excimer. © 1994 John Wiley & Sons, Inc. 相似文献