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Torsten Roth Vladislav Vasilenko Callum G. M. Benson Hubert Wadepohl Dominic S. Wright Lutz H. Gade 《Chemical science》2015,6(4):2506-2510
A simple, “click” synthetic approach to a new type of hybrid phosph(III)azane/NHC system is described. The presence of the phosphazane P2N2 ring unit, with P atoms flanking the NCN fragment and with this ring perpendicular to the binding site of the NHC, provides unique opportunities for modifying the electronic and steric character of these carbenes. 相似文献
24.
N.?V.?Yashin E.?B.?AverinaEmail author D.?A.?Vasilenko Yu.?K.?Grishin D.?I.?Osolodkin V.?A.?Palyulin T.?S.?Kuznetsova N.?S.?Zefirov 《Russian Chemical Bulletin》2017,66(8):1483-1490
3-Methylenecyclobutanecarboxylic acid and its methyl ester were used as the starting compounds for the synthesis of new spiro[2.3]hexane amino acids, the conformationally rigid analogs of γ-aminobutyric acid, namely, 5-aminospiro[2.3]hexanecarboxylic and 5-amino-spiro[2.3]hexanephosphonic acids, promising modulators of GABAergic cascades in the human central nervous system. The methods developed for the synthesis of the target amino acids are based on the reactions of catalytic [1+2] cycloaddition of diazoacetic and diazophosphonic esters to 3-substituted methylenecyclobutanes, as well as on a modified Curtius reaction for the transformation of a carboxy group to the amine one. 相似文献
25.
V. I. Zabolotskii S. V. Utin N. V. Shel’deshov K. A. Lebedev P. A. Vasilenko 《Russian Journal of Electrochemistry》2011,47(3):321-326
The current efficiencies of the water dissociation water and the voltage-current characteristics of the bipolar (asymmetric
bipolar) membranes were measured in a two-chamber electrochemical cell. The cell was formed of an MB-3 bipolar membrane or
an asymmetric bipolar membrane, which is an MA-40 heterogeneous membrane with a thin surface layer in the form of a cation-selective
homogeneous film and MA-40 and MA-41 heterogeneous monopolar membranes. The dissociation of water on MA-40 in 0.01 M sodium
chloride decreased the current efficiency of the acid and alkali both in the channel with a bipolar membrane and in the channel
with an asymmetric bipolar membrane. The effective ion transport numbers across MA-40 and MA-41 at different pH values were
determined. The water dissociation rate on MA-40 decreased at pH > 9.5. A kinetic model of the electrodialysis of a dilute
solution of sodium chloride in a two-chamber unit cell with a bipolar and anionite membranes was suggested. 相似文献
26.
For rods in which the piezoelectric and elastic layers are perpendicular to the rod axis and the lamination has a periodic structure, formulae for the effective characteristics of inhomogeneous material are obtained and the equations that describe the electroelastic state are constructed by the asymptotic method of homogenization. Such active composite elements are known as stacks. As an example, the electroelastic state of stacks executing forced harmonic vibrations under the action of an electrical load is calculated, the effective characteristics of material are found, and both the slowly varying state described by the rod theory and the rapidly varying state caused by the inhomogeneity of the layered structure are calculated. The effect of the thickness of weak adhesive layers on the electromechanical coupling coefficient, characterizing the stacks as energy convertors, is investigated. 相似文献
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Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Sverdlovsk. Translated from Prikladnaya Mekhanika, Vol. 26, No. 5, pp. 36–42, May, 1990. 相似文献
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Institute of Mechanics, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Prikladnaya Mekhanika, Vol. 27, No. 8, pp. 74–80, August, 1991. 相似文献