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An inexpensive ruthenium catalyst enabled oxidative annulations of alkynes by acrylamides with ample scope, which allowed for the preparation of 2-pyridones employing various electron-rich and electron-deficient acrylamides as well as (di)aryl- and (di)alkyl-substituted alkynes. 相似文献
3.
Ruthenium-catalyzed C-H bond arylations of indoles, thiophenes, and pyrroles were accomplished in a highly chemo- and site-selective manner through the use of removable directing groups. 相似文献
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M. K. Krasil'nikova V. I. Lygin K. V. Topchieva 《Theoretical and Experimental Chemistry》1967,2(1):67-72
This paper describes an infrared spectroscopic study of the adsorption of methanol, ethanol, acetaldehyde, ethylene, and water on two samples of yttrium oxide, one of which had dehydrating properties and the other, dehydrogenating properties. The occurrence of different surface compounds during the dehydration and dehydrogenation of alcohols is shown. Possible mechanisms for the decomposition of alcohols are discussed. 相似文献
6.
Glyavin M.Yu. Goldenberg A.L. Kuftin A.N. Lygin V.K. Postnikova A.S. Zapevalov V.E. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(2):474-483
In order to provide electron beams of powerful gyrotrons, magnetron-injection guns operating in the regime of the temperature limited current are used. The electron beam quality and gyrotron performances are defined both by the cathode emission processes and the processes occurring in the electron beam during its formation and transportation. The results of measurements of the energy spectrum and velocity spread of the gyrotron electron beam in different regimes are given. Experimental data on the parameter of efficient emission inhomogeneity for different regimes are presented, as well as the dependencies of electron beam parameters on efficient inhomogeneity of the cathode 相似文献
7.
Numerical simulation of intense helical electron beams with the calculation of the velocity distribution functions 总被引:3,自引:0,他引:3
V. K. Lygin 《International Journal of Infrared and Millimeter Waves》1995,16(2):363-376
The method of calculation of intense helical electron beams which allows to find the distribution function of electrons with respect to their transverse (oscillatory) and longitudinal velocities is developed. The initial velocity distribution function can be arbitrary. The data obtained in numerical simulation and experimental measurements for beams with various topologies are compared. The evolution of the transverse velocity distribution function with the beam current growth is traced. It is found that the transformation of the velocity distribution function may indicate a possible instability in a real beam. 相似文献
8.
V. I. Lygin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(2):304-306
A comparison of the experimental and calculated spectra of the structures of silica surfaces modified with TiCl4 shows that only monofunctional groups are formed upon modification of a dehydroxylated surface and that both mono-and bifunctional titanium oxychloride structures are formed upon modification of a hydroxylated surface. After a prolonged evacuation or thermal treatment, a crystalline titanium dioxide phase is formed on the modified silica surface. 相似文献
9.
Fragments of the zeolite structure have been calculated by the EHT method. The results are in agreement with spectral data on structural hydroxy groups of zeolites.
PMX . .相似文献
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