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991.
RemarksontheVeroneseGeneratingSubmanifoldsinMinkoskiSpaceHuConge(胡聪娥)(HenanUniversity,Kaifeng,475001)Abstract:Inthispaper,the... 相似文献
992.
J. K. Percus 《Journal of statistical physics》1977,16(3):299-309
The external potential needed to produce an arbitrary equilibrium density profile for a one-dimensional lattice gas with nearest neighbor interactions is solved exactly. The resulting sequence of direct correlation functions is shown to be of short range, and in the ferromagnetic case the even members alternate in sign at zero spin. The even Ursell distributions in this case likewise alternate in sign.Supported in part by U.S. ERDA under contract E(11-1)-3077. 相似文献
993.
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
994.
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
995.
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
996.
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
997.
Stefan Siegmund 《Journal of Differential Equations》2002,178(2):541-573
We extend Henry Poincarés normal form theory for autonomous differential equations x=f(x) to nonautonomous differential equations x=f(t, x). Poincarés nonresonance condition λj−∑ni=1 ?iλi≠0 for eigenvalues is generalized to the new nonresonance condition λj∩∑ni=1 ?iλi=∅ for spectral intervals. 相似文献
998.
Lee Dae-Won Lee Jung-Hyun Chun Bae-Hyeock Lee Kwan-Young 《Plasma Chemistry and Plasma Processing》2003,23(3):519-539
The direct hydroxylation of benzene using molecular oxygen by atmospheric pulse DC corona discharge was investigated. The conversion of benzene increased with the increase of oxygen content and input voltage but the selectivity of phenol decreased due to the formation of polymerized products. The reactivity was also influenced by the kind and content of background inert gas. By using argon as background gas, we could get 2.2% of phenol yield at 60°C and 1 atm with energy consumption of 50 W. The strategy of reductive oxidation, which added hydrogen to the reactant, was not favorable to the phenol formation in this reaction system. The polymerized product showed the oligomeric character and the analysis of its chemical structure with FT–IR was presented. 相似文献
999.
1000.
SYSTEM OF GENERALIZED VECTOR VARIATIONAL INEQUALITIES 总被引:3,自引:0,他引:3
1IntroductionA vector variational inequality(for short,VVI),as an important generalization of the clas-sical variational inequality,was first introduced and studied by Giannessi[6]in finite dimensionalEuclidean spaces.Later on,a VVI was studied and genera… 相似文献