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991.
Jacques Carmona 《manuscripta mathematica》1973,10(1):1-33
We show how the non compact imaginary roots of a non compact real semi-simple Lie algebra with respect to a Cartan subalgebra to allows us, alike the real roots of, to give a complete classification of the G-conjugacy classes of Cartan subalgebras of if Gc is a complex connected group whose algebra is the complexified of, if B is a Borel subgroup of Gc and G the analytic subgroup of Gc corresponding to the subalgebra of, we determine the G-orbits of codimension one in the boundary of an open G-orbit of the complex flag manifold Gc/B. If is a maximally compact Cartan subalgebra of contained in, we show how the imaginary non compact simple roots of allows us to determine such orbits. 相似文献
992.
Jacques De Maré 《Stochastic Processes and their Applications》1977,6(1):77-86
A model process is obtained for the behaviour of a non-differentiable but continuous stationary Gaussian process after a level crossing. It is shown that the sampled process conditioned on a crossing of a fixed level in Slepian's sense, converges weakly towards the model process, when the sample distance decreases to zero. Further it is noticed that there is no difference between conditioning on a vertical window and on a horizontal window in this case. 相似文献
993.
Novel 1,7-dihydro- or 1,2,6,7-tetrahydronaphthalene derivatives were obtained from naphthalene through a polysilylation/oxidation process as well as 1,4,6,7-tetrakis(trimethylsily)naphthalene, a regiospecific precursor of 1,4,6,7-tetrafunctional naphthalenes. 相似文献
994.
Helene Lavayssiere Jacques Satge Jacques Barrau Moussa Traore 《Journal of organometallic chemistry》1982,240(4):335-348
A new aspect of the reactivity of germanones and germathiones towards nitrilimines, nitriloxides and nitrones is investigated. The regioselectivity of the dipolar 1,3-cycloaddition reactions between germanones or germathiones and diphenylnitrilimine is discussed.
The structure of the adducts is determined from chemical or spectroscopic studies (13C NMR, IR).
Germa-oxa- or -thia-diazolines, germaoxathiazoles and germaoxathiazolidines are obtained and the thermal stability of these adducts reported. 相似文献
995.
996.
The temperature dependences of g-factor and linewidth of C11,3NiCl2,13 single crystals have been measured from 10 to 400 K. The data indicate that nickel ions in graphite behave at low temperatures like Ising ions, with a phase transition occurring at about 30 K. 相似文献
997.
Jean-Pierre Crouzeix Jacques A. Ferland Siegfried Schaible 《Mathematical Programming》1983,27(3):342-354
We consider a generalization of a linear fractional program where the maximum of finitely many linear ratios is to be minimized subject to linear constraints. For this Min-Max problem, a dual in the form of a Max-Min problem is introduced and duality relations are established. 相似文献
998.
The migratory aptitude of the ethoxycarbonyl group in the pinacol rearrangement was deduced from the structure of the products observed after treatment of 2-substituted 2,3-dihydroxy-3-phenylbutyrates with fluorosulfonic acid at 0° for 3 minutes. The migratory aptitude of ethoxycarbonyl is comparable to that of ethyl, greater than that of methyl or hydrogen, but smaller than that of phenyl. Cyclization and fragmentation reactions were also observed. 相似文献
999.
1000.
The absolute configuration of tri-o-thymotide was obtained from the crystal structure of the solvate with (R)-2-butanol in association with optical measurements. 相似文献