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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Simulation of evaporation in operation area of an evaporator is considered. We obtained a formalized model of this process and optimum conditions of an engineering system on the basis on the analysis. 相似文献
993.
994.
A. I. Olemskoĭ 《JETP Letters》2007,85(2):127-130
The complexity measure of the infinite set of self-similar hierarchically constrained ensembles is determined in the framework of the generalized combinatory approach. It is shown that, as the hierarchical coupling increases, the complexity increases to a value that decreases with increasing the dispersion of this coupling and with decreasing the branching degree of the hierarchical tree. 相似文献
995.
Dynamics of the elementary photoelectric conversion upon interaction of a single-photon mode with a bound electron in a one-dimensional rectangular potential well is considered. The spatial and temporal dynamics of the wave packet corresponding to a free photoelectron is investigated. 相似文献
996.
I. M. Lavit Nguyen Viet Trung 《Journal of Applied Mechanics and Technical Physics》2008,49(3):491-499
The thermoelastoplastic fracture mechanics problem of a thick-walled cylinder subjected to internal pressure and a nonuniform
temperature field is solved by the method of elastic solutions combined with the finite-element method. The correctness of
the solution is provided by using the Barenblatt crack model, in which the stress and strain fields are regular. The elastoplastic
problem of a cracked cylinder subjected to internal pressure and a nonuniform temperature field are solved. The calculation
results are compared with available data.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 3, pp. 173–183, May–June, 2008. 相似文献
997.
T. M. Prokop’eva V. A. Mikhailov M. K. Turovskaya E. A. Karpichev N. I. Burakov V. A. Savelova I. V. Kapitanov A. F. Popov 《Russian Journal of Organic Chemistry》2008,44(5):637-646
Bis(dialkylamide)hydrogen dibromobromates were synthesized and their reactivity was investigated in decomposition of diethylphosphonic, diethylphosphoric, and 4-toluenesulfonic acids 4-nitrophenyl esters. The nucleophilic reactivity of a typical α-nucleophile, hypobromite ion, is independent of the source of the active bromine. The cetyltrimethylammonium dibromobromate is a unique reagent for destruction of ecotoxicants. In weakly alkaline media the half-life of 4-nitrophenyl diethylphosphonate did not exceed 6 s at [BrO?] 0.02 mol l?1, and the apparent reaction rate compared to water increased ~40-fold. The main factor governing the micellar effects of surfactants is concentrating the substrate in the micellar pseudophase. 相似文献
998.
Zh. A. Krasnaya E. O. Tret’yakova V. V. Kachala S. G. Zlotin 《Russian Chemical Bulletin》2008,57(8):1671-1675
A reaction of 2,2-disubstituted 1,1-dicyanoethenes with β-dimethylaminoacrolein aminal and 3-dimethylamino-1,1,3-trimethoxypropane
leads to substituted 6,6-dicyano-1-dimethyl-aminohexatrienes and an organic salt containing 1,1,9,9-tetracyano-2,8-diphenylnona-2,4,6,8-tetraenide
as the anion and (dimethylaminopropenylidene)dimethylammonium as the cation, on the basis of which new cation-anionic polymethine
dyes were obtained.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1639–1643, August, 2008. 相似文献
999.
M. A. Katkova V. A. Ilichev A. N. Konev M. N. Bochkarev 《Russian Chemical Bulletin》2008,57(11):2281-2284
Rare-earth metal 8-hydroxyquinolinates (q) were studied as emission layers for organic light-emitting diodes. Compounds Dyq3, Tbq3, and Smq3 possess weak electroluminescence due to the emission of the ligand, and the electroluminescence of Hoq3, Tmq3, and Ybq3 is due to electronic transitions of the lanthanide ion. The best electroluminescence characteristics were demonstrated by
Scq3 and Yq3. The power efficiency of the organic light emitter based on ITO/TPD/Scq3/Yb (ITO is tin-alloyed indium oxide, TPD is N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine) is 2.6 lm W−1 at a luminance of the device of 300 cd m−2. 相似文献
1000.
V. V. Sidorchuk J. Skubiszewska-Zięba S. V. Khalameida V. A. Zazhigalov R. Leboda 《Russian Journal of Applied Chemistry》2008,81(8):1325-1331
Effect of conditions of hydrothermal and microwave synthesis of supported vanadium-phosphorus oxide catalysts in an aqueous medium on the physicochemical properties of the vanadyl hydrophosphate obtained was studied. The transformations occurring in the system were examined using X-ray phase and differential-thermal analyses, adsorption-structural method, and scanning electron microscopy. 相似文献