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951.
952.
Pd(II)‐Catalyzed CH Activation of Styrylindoles: Short,Efficient, and Regioselective Synthesis of Functionalized Carbazoles
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Rakesh K. Saunthwal Monika Patel Sonu Kumar Abhinandan K. Danodia Prof. Dr. Akhilesh K. Verma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(51):18601-18605
A novel PdII‐catalyzed approach for the direct synthesis of highly functionalized carbazoles from unprotected styrylindoles has been developed. The reaction features a variety of olefin substrates, which are readily switchable by subtle tuning of the reaction conditions. Investigations of the mechanism suggest that the C?H activation proceeds via enamine formation. 相似文献
953.
J. Lee E. Narumi C. Li S. Patel D.T. Shaw 《Physica C: Superconductivity and its Applications》1992,200(3-4):235-241
We present the results of a study of the effect of oxygen pressure on the properties of Bi---Sr---Ca---Cu---O (BSCCO) thin films grown by laser ablation. Films of the same phase, which were deposited at different oxygen pressures, show quite different properties. Here, we define the phases of BSCCO films from their c-axis lattice constants calculated from the 2θ X-ray diffraction angle of the 002 peak. In-situ films deposited at high oxygen pressure (≥ 100 mTorr) show higher critical temperatures and critical current densities. However, by post annealing, transport properties of films deposited at low oxygen pressure (several 10 mTorr) are improved significantly. With respect to this difference, the results of X-ray diffraction and energy dispersive X-ray spectroscopy studies, and Hall effect measurements are discussed. 相似文献
954.
955.
956.
M. Markytan P. Johnson P. Mason H. Muirhead G. Patel G. Warren G. Ekspong S.O. Holmgren S. Nilsson R. Stenbacka Ch. Walck 《Nuclear Physics B》1978,143(2):263-284
Cross sections have been determined for the inclusive production of vector and tensor (f, A2±) mesons in reactions at 9.1 GeV/c for both annihilation and non-annihilation processes. Distributions in the Feynman variable x and transverse momentum squared, pT2, have been examined for the ?0, ω and f mesons. The slopes for pT2 appear to be exponential and decrease with increasing particle mass for both annihilation and non-annihilation reactions, furthermore the slopes have consistently higher values for non-annihilation reactions. Comparisons with other data indicate that the ratio ?0/π? is independent of antiproton momentum in annihilation processes. 相似文献
957.
S. M. Patel 《Mathematische Nachrichten》1977,78(1):357-361
The aim of this note is to study the spectral properties of the LUECKE's class R of operators T such that ‖(T – zI)?1‖=1/d(z, W(T)) for all z?CLW(T), where CLW(T) is the closure of the numerical range W(T) of T and d(z, W(T)) is the distance from z to W(T). The main emphasis is on the investigation of those properties of operators of class R which are either similar to or distinct from those of operators satisfying the growth condition (G1). 相似文献
958.
Adsorption of cellulose triacetate from its chloroform solution on calcium silicate has been studied. The adsorption follows first order kinetics. The adsorption data are adequately described by the Langmuir isotherm indicating that the adsorbed polymer molecules behave as rigid molecules in the adsorbed state. An attempt has been made to fractionate cellulose triacetate employing the adsorption technique. 相似文献
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960.