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1.
V. N. Kruchinin S. M. Repinskii L. L. Sveshnikova 《Journal of Structural Chemistry》1993,34(6):938-945
Thermodesorption processes of mono-and multilayers of fatty acids and their salts with 14 to 24 carbon atoms were investigated by ellipsometry and IR spectroscopy. Cadmium, calcium, strontium, and barium salt layers, unlike the layers of pure acids, have a complex phase composition which includes not only separate acid and salt phases, but also intermediate acid-salt forms. The initial phase composition of multilayer systems determines their thermodesorption spectrum observed upon heating the samples. It was found that before the removal of molecules to the gaseous phase, phase transitions are possible in the films, similar to those observed in crystals and caused by the change of molecular conformations in the layer. Energy characteristics of thermodesorption processes are estimated for pure acid layers and for separate phases in salt layers. Possible qualitative models of the processes are discussed.Institute of Semiconductor Physics. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 6, pp. 123–130, November–December, 1993.Translated by L. Chernomorskaya 相似文献
2.
M. K. Kovalev K. P. Mogil’nikov O. I. Semenova V. N. Kruchinin M. S. Mel’gunov 《Bulletin of the Lebedev Physics Institute》2009,36(12):365-366
The sensitivity of chemical sensors depends on the number of receptors on the surface; hence, an important role is played
by the accessible support surface. Films based on silica mesoporous mesophase materials feature the highest specific surface
area for silica materials, and their walls can be modified by various functional groups. In this paper, we propose to use
mesoporous mesophase films as supports of sensitive elements for Cr3+ ions. 相似文献
3.
G.V. Beketov S.M. Zombkovsky A.B. Kaidalov B.S. Konovalov S.P. Kruchinin N.A. Pojidaeva Ya.M. Selector V.N. Shulyachenko V.F. Turov 《Nuclear Physics B》1973,59(1):265-272
Helicity conservation in the reaction π? p → pA1 at 4.45 GeV/c has been studied using 50 cm and 55 cm liquid hydrogen bubble chambers. In the Jackson and the helicity frames the dependence of the ? matrix elements on the four-momentum transfer squared to the proton (t) for A1 maximum decay has been calculated. The obtained data are in a good agreement with t-channel helicity conservation. The t-channel dependence of the ? matrix elements in the mentioned frames is in good agreement with that calculated using the Regge π-pole exchange model (it is suggested that the A1 maximum nature is explained by a kinematical effect of the Deck type). 相似文献
4.
A theory of persistent spectral hole burning is developed. Within a simple, exactly solvable model (a cubic potential well with infinitely high walls in a uniform electric field), the energy spectrum and the rate of electron-hole pair generation are determined with due regard for the effect of the field induced in this case owing to the spatial separation of electrons and holes. The dependence of the energy spectrum on the field vector orientation relative to the symmetry axes of a quantum dot is studied. An expression describing the shape of the differential spectrum is derived. 相似文献
5.
Yu. G. Vlasov S. S. Levichev A. A. Kruchinin 《Russian Journal of Applied Chemistry》2012,85(6):940-944
A new ligand based on two pyrazole cycles linked with each other was synthesized. Its interaction with Cu(II), Ni(II), Co(II), Mn(II), Cr(III), Zn(II), and Cd(II) cations in ethanol was studied by the spectrophotometric method. 相似文献
6.
Yu. G. Vlasov S. S. Levichev A. A. Kruchinin Yu. E. Ermolenko Bing-Joe Hwang 《Russian Journal of Applied Chemistry》2008,81(2):241-246
Dye molecules were suggested as a sensitive element for an optical sensor of parameters determining the efficiency of a fuel cell with a proton-exchange membrane, in which a water-methanol mixture is used as a fuel. The sensitivity of representatives of three different types of dyes to the concentrations of protons and methanol was examined. 相似文献
7.
SuperQuat 5,5-dimethyl-4-iso-propyloxazolidin-2-one as a mimic of Evans 4-tert-butyloxazolidin-2-one
Bull SD Davies SG Garner AC Kruchinin D Key MS Roberts PM Savory ED Smith AD Thomson JE 《Organic & biomolecular chemistry》2006,4(15):2945-2964
The incorporation of a gem-dimethyl group at the 5-position of a chiral oxazolidinone biases the conformation of the adjacent C(4)-stereodirecting group such that the gem-dimethyl-4-iso-propyl combination mimics a C(4)-tert-butyl group, providing higher levels of stereocontrol than a simple 4-iso-propyloxazolidinone. The generality of this principle is demonstrated with applications in stereoselective enolate alkylations, kinetic resolutions, Diels-Alder cycloadditions and Pd-catalysed asymmetric acetalisation reactions. 相似文献
8.
Davies SG Garner AC Goddard EC Kruchinin D Roberts PM Rodriguez-Solla H Smith AD 《Chemical communications (Cambridge, England)》2006,(25):2664-2666
Conjugate addition of homochiral lithium amides to methyl 4-(N-benzyl-N-allylamino)but-2-enoate, chemoselective N-deprotection and concomitant cyclisation, followed by enolate functionalisation and deprotection allows access to syn- and anti-3,4-disubstituted aminopyrrolidines in > 98% d.e. and > 98% e.e. 相似文献
9.
Kruchinin V. N. Perevalov T. V. Aliev V. Sh. Iskhakzai R. M. Kh. Spesivtsev E. V. Gritsenko V. A. Pustovarov V. A. 《Optics and Spectroscopy》2020,128(10):1577-1582
Optics and Spectroscopy - The optical properties and composition of thermal silicon oxide thin films processed in a hydrogen electron cyclotron resonance plasma have been studied by ellipsometry,... 相似文献
10.
Davies SG Garner AC Goddard EC Kruchinin D Roberts PM Smith AD Rodriguez-Solla H Thomson JE Toms SM 《Organic & biomolecular chemistry》2007,5(12):1961-1969
The diastereoselective conjugate addition of homochiral lithium amides to methyl 4-(N-allyl-N-benzylamino)but-2-enoate has been used as the key step in a simple and efficient protocol for the preparation of 3,4-substituted aminopyrrolidines. This protocol provides a complementary and stereoselective route to both anti- and syn-3-amino-4-alkylpyrrolidines as well as anti- and syn-3-hydroxy-4-aminopyrrolidines, in high de and ee viabeta-amino enolate functionalisation. This methodology has been applied to the synthesis of anti-(3S,4S)- and syn-(3R,4S)-3-methoxy-4-(N-methylamino)pyrrolidine. 相似文献