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91.
92.
J.M. Boente L. Castedo A. Rodriguez de Lera J.M. Saá R. Suau M.C. Vidal 《Tetrahedron letters》1984,25(17):1829-1830
Three new phenolic cularines have been isolated from Sarcocapnos and Corydalis species. Their structures have been elucidated on the basis of spectroscopic studies and chemical transformations. 相似文献
93.
We study immersed prescribed mean curvature compact hypersurfaces with boundary in Hn+1(-1). When the boundary is a convex planar smooth manifold with all principal curvatures greater than 1, we solve a nonparametric Dirichlet problem and use this, together with a general flux formula, to prove a parametric uniqueness result, in the class of all immersed compact hypersurfaces with the same boundary. We specialize this result to a constant mean curvature, obtaining a characterization of totally umbilic hypersurface caps. 相似文献
94.
A simple method for determining the surface slope of a specimen under test in the high-sensitivity grating interferometry setup is proposed. The information on the derivative of out-of-plane displacement is obtained by software subtraction of two primary interferograms: a conventional one and one with diffraction orders laterally displaced in the image plane. Very good coincidence between the theoretical and experimental results has been obtained. The method can be used for studying static and transient events depending on the fringe pattern analysis method used. 相似文献
95.
M.J. Campello L. Castedo D. Dominguez A.Rodriguez de Lera J.M. Saá R. Suau E. Tojo M.C. Vidal 《Tetrahedron letters》1984,25(51):5933-5936
Structures 1a, 3 and 6 were deduced for the new oxoisocularine alkaloids, oxosarcophylline, yagonine and aristoyagonine, respectively, on the basis of spectroscopic studies and synthesis. 相似文献
96.
97.
98.
Salvatori Mdel R Abou-Jneid R Ghoulami S Martin MT Zaparucha A Al-Mourabit A 《The Journal of organic chemistry》2005,70(20):8208-8211
[Chemical reaction: see text] Various substituted 2-aminotetrahydroazolopyridines and 2-aminohexahydroazolopyridines have been prepared by bromine-mediated addition of protected guanidine or urea to hydropyridine derivatives. The pH-dependent regioselective cleavage of the resulting aminal function led to the 2-aminoazole products III. The yields of the bicycles of type II, and their conversion into azoles III depends on the electronic properties of the substituents on the nitrogen of the tetrahydopyridine. 相似文献
99.
100.
The order parameter fluctuation spectrum in an isotopically disordered KH2PO4 type crystal has been evaluated as a function of the deuterium content using Mori's continued fraction representation. In contrast to a pure system we have now two narrow central peaks and two overdamped soft modes. The results show that the static central peak observed by light scattering in paraelectric KH2PO4 cannot be produced by naturally abundant deuterium. 相似文献