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31.
P.A. Loboda N.A. Smirnov A.A. Shadrin N.G. Karlykhanov 《High Energy Density Physics》2011,7(4):361-370
We present a simulation of absorption of femtosecond laser pulses by a copper target. The modeling involved thermodynamic functions calculated by using a first-principles full-potential linear muffin-tin orbital method and chemical-picture-based model of dense plasma utilizing a superconfiguration approach. The results of the simulation are compared to experimental and other theoretical data. The role of the electron-ion energy exchange is analyzed and further work on detailed improvement of the presented theoretical model is discussed. 相似文献
32.
Sergey V. Ryabukhin Andrey S. Plaskon Semen S. Bondarenko Oleksandr O. Grygorenko Oleg V. Shishkin 《Tetrahedron letters》2010,51(32):4229-812
Chlorotrimethylsilane-promoted Biginelli-type reaction of ethyl 2,4-dioxo-4-phenylbutanoate, benzaldehyde, and various (thio)ureas is explored. The outcome of the reaction depends on the structure of the (thio)urea used and is strongly affected by the acceptor electronic properties of the COOEt substituent in the molecule of the starting β-dicarbonyl compound. The di- and tetrahydropyrimidine derivatives obtained possess two functional groups with orthogonal reactivity, and thus represent promising building blocks for drug discovery. 相似文献
33.
34.
Dr. Oleksandr S. Kanishchev Prof. William R. Dolbier Jr. 《Angewandte Chemie (International ed. in English)》2015,54(1):280-284
Current approaches to prepare SF5‐substituted heterocycles during the synthesis of targeted heterocyclic compounds require the use of SF5‐functionalized aryl or alkyne reagents or SF5Cl as a source of the SF5 functional group. Herein we report that excess oxidative fluorination of 2,2′‐dipyridyl disulfide with a KF/Cl2/MeCN system leads to the formation of thirteen new 2‐pyridylsulfur chlorotetrafluorides (2‐SF4Cl‐pyridines). These molecules are found to undergo further chlorine–fluorine exchange reactions by treatment with silver(I) fluoride enabling ready access to a series of ten new substituted 2‐pyridylsulfur pentafluorides (2‐SF5‐pyridines). This is the first preparatively simple and readily scalable example of the transformation of an existing heterocyclic sulfur functionality to prepare SF5‐substituted heterocycles. 相似文献
35.
Reis H Loboda O Avramopoulos A Papadopoulos MG Kirtman B Luis JM Zaleśny R 《Journal of computational chemistry》2011,32(5):908-914
Electronic and vibrational nuclear relaxation (NR) contributions to the dipole (hyper)polarizabilities of the endohedral fullerene Li@C(60) and its monovalent cation [Li@C(60)](+) are calculated at the (U)B3LYP level. Many results are new, while others differ significantly from those reported previously using more approximate methods. The properties are compared with those of the corresponding hypothetical noninteracting systems with a valence electron transferred from Li to the cage. Whereas the NR contribution to the static linear polarizabilities is small in comparison with the corresponding electronic property, the opposite is true for the static hyperpolarizabilities. A relatively small, but non-negligible, NR contribution to the dc-Pockels effect is obtained in the infinite frequency approximation. 相似文献
36.
Kovalenko OO Brusylovets OA Kinzhybalo V Lis T Brusilovets AI 《Dalton transactions (Cambridge, England : 2003)》2011,40(18):4814-4817
The low-coordinate phosphorus compounds (Me(3)Si)(2)N-P=NSiMe(3), (Me(3)Si)(2)N-P(=S)=N(t)Bu and (Me(3)Si)(2)N-P(=NSiMe(3))(2) react with ((i)PrO)(3)M≡M(O(i)Pr)(3) (M = Mo, W) to form four- and five-membered metallacycles with intact endocyclic or exocyclic M≡M triple bonds. The first four-membered planar metallacycles, containing an M≡M triple bond were obtained in reaction with (Me(3)Si)(2)N-P=NSiMe(3). 相似文献
37.
MicroRNAs as biomarkers of disease onset 总被引:1,自引:0,他引:1
Ciesla M Skrzypek K Kozakowska M Loboda A Jozkowicz A Dulak J 《Analytical and bioanalytical chemistry》2011,401(7):2051-2061
38.
Solozhenko VL Kurakevych OO Sokolov PS Baranov AN 《The journal of physical chemistry. A》2011,115(17):4354-4358
Kinetics of the wurtzite-to-rock-salt transformation in ZnO has been studied in the 5-7 GPa pressure range at temperatures below the activation of diffusion processes. The detailed analysis of non-isothermal experimental data using the general evolution equation describing the kinetics of direct phase transformations in solids allowed us to study the kinetic particularities of both nucleation and growth of the rock-salt phase in parent wurtzite ZnO. The main rate-limiting processes are thermally activated nucleation (E(N) = 383 kJ mol(-1) at 6.9 GPa) and thermally nonactivated (most probably quasi-martensitic) growth (k(G) = 0.833 min(-1) at 6.9 GPa). The high impact of thermal deactivation of nucleation places has been evidenced in the case of slow heating, which indirectly indicates that the rs-ZnO nucleation places are mainly produced by pressure-induced stresses in the parent phase. 相似文献
39.
Oleksandr O. Kurakevych 《高压研究》2013,33(1):48-52
Novel superhard phases are expected to be found among various high-pressure polymorphs of light element compounds. Besides diamond-like phases, the icosahedral boron-rich solids are of particular interest because they could combine high hardness with advanced electronic and phonon transport properties, lightness, high thermal and chemical stability. Here we review some recent results on high-pressure synthesis of novel boron-rich solids. 相似文献
40.
L. I. Loboda I. V. Sokolova K. M. Degtyarenko A. Ya. Il'chenko A. V. Kropachev 《Russian Physics Journal》1988,31(6):514-517
In this report the effects of 3CN substitutions on the spectral luminescence and lasing properties of oxy- and diethylaminocoumarins are studied. In both classes of coumarins the CN group decreases the tuning region of the maximum lasing wavelengths: in aminocoumarine as a result of decreased intermolecular interaction with the solvents, and in the oxy- as a result of a shift in the equilibrium of protolytic reactions towards anion forms. As a result, the lasing efficiency of anion forms of 3CN oxycoumarins increases. The lasing properties of aminocoumarins decrease with the given substitutions, while the probability increases for the formation of nonplanar molecular conformations.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 103–106, June, 1988. 相似文献