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31.
E. A. Vasil’chenko I. A. Kudryavtseva A. Ch. Lushchik Ch. B. Lushchik A. A. Maaroos 《Physics of the Solid State》1998,40(7):1128-1134
Production of F, Cl
3
−
, Ag0, and Tl0 centers in RbCl:Ag and RbCl:Tl crystals by photons having energies ranging from 5 to 10 eV has been studied at 295 and 180
K. It is shown that creation of near-impurity excitations is accompanied by formation of F centers localized in the vicinity of Ag+ and Tl+ ions. F centers are produced in direct optical generation of self-trapped excitons. In addition to the well-known mechanism of F-H pair production in nonradiative recombination of electrons with self-trapped holes, a hole-electron process has been revealed
for the first time to operate in RbCl:Ag having deep electron traps. By this mechanism, F-H pairs appear in the following sequence of stages: thermally stimulated unfreezing of hopping diffusion of self-trapped holes
(V
K centers), tunneling electron transfer from Ag0 to the approaching V
K centers, and subsequent nonradiative decay of triplet self-trapped excitons near Ag+ ions.
Fiz. Tverd. Tela (St. Petersburg) 40, 1238–1245 (July 1998) 相似文献
32.
33.
G. I. Kurochkina N. A. Kudryavtseva M. K. Grachev S. A. Lysenko L. K. Vasyanina E. E. Nifant’ev 《Russian Journal of General Chemistry》2007,77(3):442-449
A possibility of formation of various inclusion complexes and conjugates of β-cyclodextrin and its silyl derivatives with the medicine preparation “Ibuprofen” and its synthetic precursors in dependence of nature of solvent and size of cyclodextrin cavity is demonstrated. 相似文献
34.
L. Ya. Zakharova A. R. Ibragimova F. G. Valeeva L. A. Kudryavtseva 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(1):23-27
The catalytic effect of reverse micellar systems in alkaline hydrolysis of phosphonic acid esters is to a considerable extent determined by the structure of the substrate and surfactant and the nature of the oil phase but weakly depends on the surface potential of the aggregates. AOT-butanol-decane-water, sodium dodecyl sulfate-butanol-decane-water, and cetyltrimethylammonium bromide-butanol-decane-water microemulsions exhibit specific catalytic properties rather than catalytic properties intermediate between those of the surfactant-alkane-water and surfactant-alkanol-water three-component systems. 相似文献
35.
A. A. Kudryavtseva M. P. Kurlykin A. V. Tenkovtsev A. P. Filippov 《International Journal of Polymer Analysis and Characterization》2017,22(6):526-533
Thermoresponsive graft copolymers with alkylene-aromatic polyester main chain and poly-2-ethyl-2-oxazoline side chains were synthesized. Two copolymer samples which differed in grafting density (0.5 and 0.7) were studied using dynamic and static light scattering and turbidimetry in aqueous solutions at concentration 0.0053?g?cm?3. Hydrodynamic radii of scattering objects and their contribution to light scattering were obtained as a function of temperature in a wide temperature interval. Temperatures of phase separation were found out. Effect of grafting density on the copolymer behavior in aqueous solutions upon heating was determined. In particular, the phase separation temperature reduces with the decreasing grafting density. 相似文献
36.
Mtei RP Lyashenko G Stein B Rubie N Hille R Kirk ML 《Journal of the American Chemical Society》2011,133(25):9762-9774
The electronic structure of a genuine paramagnetic des-oxo Mo(V) catalytic intermediate in the reaction of dimethyl sulfoxide reductase (DMSOR) with (CH(3))(3)NO has been probed by electron paramagnetic resonance (EPR), electronic absorption, and magnetic circular dichroism (MCD) spectroscopies. EPR spectroscopy reveals rhombic g- and A-tensors that indicate a low-symmetry geometry for this intermediate and a singly occupied molecular orbital that is dominantly metal centered. The excited-state spectroscopic data were interpreted in the context of electronic structure calculations, and this has resulted in a full assignment of the observed MCD and electronic absorption bands, a detailed understanding of the metal-ligand bonding scheme, and an evaluation of the Mo(V) coordination geometry and Mo(V)-S(dithiolene) covalency as it pertains to the stability of the intermediate and electron-transfer regeneration. Finally, the relationship between des-oxo Mo(V) and des-oxo Mo(IV) geometric and electronic structures is discussed relative to the reaction coordinate in members of the DMSOR enzyme family. 相似文献
37.
Karin Cvetko-Vah Damjana Kokol Bukov?ek Toma? Ko?ir Ganna Kudryavtseva 《Acta Mathematica Hungarica》2011,131(1-2):1-24
We prove that the minimal cardinality of a semitransitive subsemigroup in the singular part $\mathcal{I}_{n}\setminus \mathcal{S}_{n}$ of the symmetric inverse semigroup $\mathcal{I}_{n}$ is 2n?p+1, where p is the greatest proper divisor of n, and classify all semitransitive subsemigroups of this minimal cardinality. 相似文献
38.
The influence of the detergentless water/oil microemulsion formed in then-hexane-water-2-propanol system on the kinetics of the hydrolysis of di(p-nitrophenyl) methylphosphonate under the conditions of general base catalysis by primary, secondary, and tertiary aliphatic
amines was investigate. The leveling of the catalytic rate constants and basicities of the amines was found for this reaction
in a microemulsion. The catalytic rate constants for the amines containing hydrophilic groups increase in microemulsions as
compared to those in an aqueous medium, while the catalytic constants for the amines containing hydrophobic groups decrease.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1339–1342, July, 1998. 相似文献
39.
40.
E. P. Zhil'tsova L. A. Kudryavtseva G. A. Gainanova A. P. Timosheva S. S. Lukashenko A. I. Konovalov 《Russian Journal of General Chemistry》2005,75(10):1603-1609
The aggregation in polyethylenimine-chloroform and cetyltrimethylammonium bromide-polyethylenimine-chloroform systems is studied by dielcometric titration. Inverse micelles of cetyltrimethylammonium bromide catalyze the phosphorylation of hydroxybenzylated polyethylenimines in chloroform. The dependence of parameters of the micelle-catalyzed reaction on the structure and concentration of polyethylenimine and on the reaction temperature is studied. The inverse micelles affect the complexation of polyethylenimines with 4-nitrophenol. 相似文献