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991.
关于hilbert-ingham不等式和它的应用 总被引:5,自引:1,他引:4
本文给出(i)hilbert不等式和hilbert-ingham不等式一些有意义的共同改进;(ii)一些fejer-riesz型不等式的改进和(iii)hardy不等式的改进. 相似文献
992.
RemarksontheVeroneseGeneratingSubmanifoldsinMinkoskiSpaceHuConge(胡聪娥)(HenanUniversity,Kaifeng,475001)Abstract:Inthispaper,the... 相似文献
993.
G Athithan 《Pramana》1995,45(6):569-582
This paper addresses itself to a practical problem encountered in using iterative learning rules for associative memory models.
The performance of a learning rule based on linear programming which overcomes this problem is compared with that of a representative
iterative rule by numerical simulation. Results indicate superior performance by the linear programming rule. An algorithm
for computing radii of maximal hyperspheres around patterns in the state space of a model is presented. Fractional volumes
of basins of attractions are computed for the representative iterative rule as well as the linear programming rule. With the
radii of maximal hyperspheres as weight factors for corresponding patterns to be stored, the linear programming rule gives
rise to the maximal utilisation of the state space. 相似文献
994.
Raymond M. Fuoss 《Journal of solution chemistry》1986,15(3):231-235
The isodielectric rule is a corollary of the theoretical equation K=(4Na3/3000) exp (e2/aDkT) derived for primitive model electrolytes. Real systems, especially those involving small ions in structured solvents, do not follow the rule because energies of short range system-specific interactions contribute to g, the difference in free energy between paired and unpaired ions. g=–kT ln (K/Vm), where VM is the molar volume (in liters) of the solvent. The thermodynamic constant Ka=ap/(a±)2, where ap is the Lewis activity of the pairs and a± that of cation and anion; for ideal solutes, activity=mole fraction. Incidentally, ln K calls for an undefinable operation: only pure numbers have logarithms. 相似文献
995.
Variations of activity coefficients in concentrated electrolyte solutions at constant lonic strength
F. W. J. Huijgen C. L. de Ligny A. G. Remijnse N. J. Ruitenbeek 《Journal of solution chemistry》1977,6(3):149-181
Measurements of different types on various (trace) electrolytes in HClO4–Na(Li)ClO4 solutions at several (constant) values of the ionic strength have been used to determine the variation of their activity coefficients with changing amount of perchloric acid in the solution. These variations (with respect to the hydrogen ion) differ considerably among different cations and anions. The results for the alkali metal ions and the anions are interpreted in the light of the recent work of Pitzer on short-range ionic interactions. The results for the cations with outerd-electrons and the alkaline earth metal ions are interpreted in terms of ion-solvent interactions. It is concluded that the use of HClO4–NaClO4 solutions of high ionic strength (rather than the use of HClO4–LiClO4 solutions) is advisable in studies where the variation in activity coefficients must be accounted for. Finally, it is shown that the usual interpretation of the influence of the salt medium in studies of complex equilibria and reaction kinetics is sometimes questionable. 相似文献
996.
K.O. Bowman H.K. Lam L.R. Shenton 《Journal of Computational and Applied Mathematics》1984,10(2):229-244
Exact bounds for the mean value of a fractional moment, such as the sample standard deviation, are considered. These bounds are compared with those found by summation techniques applied to computer extended series. An expansion involving an arbitrary parameter is introduced, and now best bounds are found by optimization. There are applications to bounds for a certain class of quadrature problem. 相似文献
997.
Nathan Habegger 《Topology and its Applications》1984,17(2):131-143
For a 2n?m connected map from an n-dimensional complex to a m-dimensional manifold, an obstruction to embedding up to homotopy type is defined. The vanishing of this obstruction is a necessary and sufficient condition (in the 2n?m connected case, 2n?m ? 2, m?n ?3) to obtain an embedding up to homotopy type. In case the target manifold is Euclidean space, it is shown that the obstruction vanishes if and only if certain Thom operations are trivial. A classification theorem is given in the 2n?m+1 connected case. 相似文献
998.
Nistor D. Miron N. D. Surpateanu G. G. Azzouz A. 《Journal of Thermal Analysis and Calorimetry》2004,76(3):913-920
The present work tries to emphasize the effect of acid/basis properties of montmorillonite type clays by ion exchange with
cations of different natures. The acidity and basicity measuring was made by thermo programated desorption (TPD)1,2, using
ammonia like basis agent and carbon dioxide like acid agent. With TPD method we can determine acid/basis proprietes by measuring
of the quantity of the ammonia and carbon dioxide termodesorbed. Clays are crystalline aluminosilicates, similar with the
zeolyts, who presents the property of ion exchanging. That propriety can be applicated for pollutants cations from aquatic
solutions. Ion exchanging propriety depends of a lot of factors: the cation nature, the valence and the ionic ray of the cation
present in the impregnated solution. That's an advantage for depollution process of heavy metals by fixing of these metals
by montmorillonite structure. By using TPD metod we can obtaine a caracteristic diagram.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
刘志军 《Annals of Differential Equations》2004,20(2):125-132
In this paper, by means of Mawhin's coincidence degree theory and somenew techniques, sufficient conditions for the global existence of positive periodicsolution to a class of neutral type competitive system with delays are obtained. 相似文献
1000.
E. E. Sinaiskii 《Functional Analysis and Its Applications》2002,36(4):324-327
Two constructions of translation continuous functionals on the space of bounded continuous functions on a locally compact group are introduced and the properties of these functionals related to the notion of support of a functional are considered. 相似文献