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151.
Diethyl-2,2′-bipyridyl-palladium(II) is synthesized and its decomposition reactions in absence and presence of methyl acrylate are compared with those of the corresponding nickel and platinum complexes. Depending on the reaction conditions either CC-coupling or disproportionation can be induced. 相似文献
152.
The main purpose of this article is to investigate the problem of (ε, δ)-stochastic controllability for linear systems of evolution type in infinite-dimensional spaces, wherein the controls are subjected to norm-bounded constrained sets. Some basic prerequisites of infinite-dimensional measures, in particular, Gaussian distributed type, are discussed. Corresponding to this measure, various properties of (ε, δ)-stochastic attainable sets in Hilbert spaces are studied. Necessary and sufficient conditions for (ε, δ)-stochastic controllability with respect to Hilbert space valued linear systems are obtained. Relationships with the deterministic counterpoint are noted. Pursuit game problems are also considered. Examples on systems governed by stochastic linear partial differential equations and stochastic differential delay equations are given for illustration. 相似文献
153.
Thermal mutagenesis has been associated with cleavage of the glycosidic bond and modification of the base structure. Using deoxynucleosides as models, thermal analysis has been utilized to determine the influence of structure on relative ease of these thermolysis reactions. Differential enthalpic analyses of series of crystalline ribonucleosides indicate that they are more resistent to glycosidic cleavage than are the corresponding 2′—deoxyribonucleosides. This difference in thermal stability is attributed to the retarding influence of the 2′-hydroxyl group on the initiation of ion pair formation in the proposed cyclic transition state. Cytosine exhibits a unique behavior insofar as partial deamination of the base occurs, subsequent to cleavage from the sugar, to yield uracil as indicated by a combined DSC-TLC analysis. 相似文献
154.
Aromatic 1,2-bisamides undergo thallium (III) promoted oxidative intramolecular cyclization to generate new 5-membered heterocyclic rings. Formation of -quinone was shown to be a minor pathway in one case. 相似文献
155.
J.G.M. de Lau R.M. van den Heuvel A. Broese van Groenou 《Journal of Physics and Chemistry of Solids》1974,35(9):1073-1080
By using special preparation techniques the amounts of trivalent cobalt present in irondeficient Ni-Zn-Co ferrites have been varied.Co3+ concentrations have been measured very accurately by careful chemical analyses. It has been shown that under normal sintering conditions, e.g. 1200°C in oxygen, the amount of Co3+ just compensates the iron deficiency. The cation vacancy concentration is low. Cation vacancies are formed at lower temperatures near pores and grain boundaries. 相似文献
156.
157.
The stereospecific syntheses of the four isomers of 6-formyl-5,6-epoxy hexanoic acid methyl ester , , and from Z-deoxy-D-ribose have allowed the preparation of methyl esters of LTA4, , and its three unnatural isomers. 相似文献
158.
Estimation of shifted sums of Fourier coefficients of cusp forms plays crucial roles in analytic number theory. Its known region of holomorphy and bounds, however, depend on bounds toward the general Ramanujan conjecture. In this article, we extended such a shifted sum meromorphically to a larger half plane Res>1/2 and proved a better bound. As an application, we then proved a subconvexity bound for Rankin–Selberg L-functions which does not rely on bounds toward the Ramanujan conjecture: Let f be either a holomorphic cusp form of weight k, or a Maass cusp form with Laplace eigenvalue 1/4+k2, for . Let g be a fixed holomorphic or Maass cusp form. What we obtained is the following bound for the L-function L(s,fg) in the k aspect:
L(1/2+it,fg)k1−1/(8+4θ)+ε,