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191.
192.
We introduce an interpolation scheme to generate a class of irregular surfaces. The analysis is first carried out for a triangleT. We define the function ? on a subsetX, dense inT. In terms of the construction parameters of ?, we establish sufficient conditions for its uniform continuity so that it would be possible to extend it to a continuous function on the whole ofT. We do the same analysis in the case of a rectangleR. 相似文献
193.
The first successful preparation of 14,36-didehydro pristinamycins IIA and IIB is reported via different strategies. 相似文献
194.
Christian A.G.N. Montalbetti Thomas S. Coulter Serge G. Reignier Charlotta Grånäs Jakob Felding 《Tetrahedron letters》2006,47(33):5973-5975
We have developed synthetic protocols to generate 2-alkyl, 2-aryl and 2-acetylenyl substituted 4,6-diamino-1,3,5-triazines from the corresponding 2-chloro compound. 相似文献
195.
196.
Serge Lang 《Annali di Matematica Pura ed Applicata》1965,70(1):229-234
Summary A curve contained in a product of multiplicative groups passing through the origin, and containing infinitely many torsion
points is a subgroup. The analogous statement on abelian varieties is discussed and reduced to an analogue of the irreducibility
of the cyclotomic equation.
In memory of Guido Castelnuovo in the recurrence of the first centenary of his birth. 相似文献
197.
The solution of a stationary boundary value problem on a domain with conical points has singularities near these points. Here we first consider existence results in appropriate weighted Sobolev spaces in order to incorporate the singularities. We secondly use these results to prove existence, uniqueness and regularity of solutions of non-autonomous second order evolution equations on such domains. 相似文献
198.
We study the regularity of solutions of interface problems for the Poisson equation in axisynunetric domains. The Fourier decomposition of the 3D-problem into a sequence of 2D-variational equations end uniform (with respect to the sequence parameter) a prior; estimates of their solutions are derived. Some non-tensorial singular functions describing the behaviour of the solution near interface edges are given and the smoothness of the stress intensity distribution as well as the tangential regularity are characterized in tenns of Sobolev spaces. In a forthcoming part II of this paper, the results will be applied to error estimates of the so-called Fourier-finite-element method for solving approximately elliptic interface problems in 3D. 相似文献
199.
Michel Rouillard Serge Geribaldi Marcel Azzaro 《Magnetic resonance in chemistry : MRC》1981,16(2):94-97
The configurational and conformational assignments of the carbonyl group in the Z- and E-1-(3-substituted-5,5-dimethyl-2-cyclohexen-1-ylidene)-2-butanones are carried out using only the through-space effects of the carbonyl group. It is demonstrated that, regardless of the Z- or E-configuration or the nature of the substituent in position 3, the conformation of the carbonyl group is always s-cis. 相似文献
200.
Serge L. Beaucage 《Tetrahedron letters》1984,25(4):375-378
A highly selective activation of bis-(pyrrolidino) methoxyphosphine by 4,5-dichloroimidazole has been developed and successfully used in the preparation of deoxynucleoside phosphoramidites. 相似文献