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181.
V. Yu. Mat’ev 《Technical Physics》2003,48(3):303-310
The distribution of the two-dimensional gas velocity inside ion-irradiated laser cells is considered for low ion energy deposits into the gas. It is shown that, if the energy deposit is smoothly nonuniform, the twodimensional motion has two quasi-one-dimensional components: the longitudinal gas velocity is practically uniform across the cell and depends on the transversely averaged energy deposit, while the transverse velocity component depends on the difference between the local energy deposit and energy deposit averaged over the transverse direction. 相似文献
182.
Al. Ivanov 《International Journal of Theoretical Physics》2004,43(1):77-87
The notion of Fock theory is introduced in the framework of quantum logics, which are here orthomodular atomic lattices satisfying the covering property. It is shown that there are some fundamental facts concerning particles, which may be successfully discussed in this general context. One of these facts is to establish the theoretical conditions for considering particles as sharply defined entities. The other refers to the theoretical circumstances, which almost impose to consider that some particles have a structure, meaning they are composed from other particles. This last problem is strongly related with the conservative time evolutions. 相似文献
183.
184.
Three-dimensional laminar forced convection including steady-periodic transition is investigated up to periodic-chaotic transition
in the fully developed region of coolant passages with staggered arrays of pin fins. Comparative examples concern overall
pressure losses and heat transfer characteristics of circular, square and elliptical pins made of nickel and copper. In the
numerical model, transient conjugate heat transfer is assumed and space periodicities in pressure, velocity components and
temperatures are taken into account. In the range of operative conditions investigated, overall friction factors increase
almost linearly with the Reynolds number, while the increase of overall Nusselt numbers with the Reynolds number is characterized
by two slope changes connected with the onset of streamwise vortices, and the shedding of transverse vortices, respectively.
The use of copper, instead of nickel, increases the overall Nusselt number with all shapes, but is particularly beneficial
to the elliptical section. Square pins are characterized by the highest values of friction factors, but are also the best
performers as far as convection enhancing is concerned. The reverse is true for the elliptical pins which are characterized
by the lowest values of friction factors, but are the worst performers as far as convection enhancing is concerned. On the
basis of overall performances, the elliptical pins made of copper are the best choice, at least in the upper range of Reynolds
numbers investigated. 相似文献
185.
A. I. Kolesnikov I. A. Kaplunov I. V. Talyzin S. A. Tret’yakov O. V. Gritsunova E. Yu. Vorontsova 《Crystallography Reports》2008,53(7):1144-1149
A computer simulation and measurements of the light transmittance of germanium and paratellurite crystals of different thickness
were used to show that, at scattering probabilities of photons comparable to their absorption probabilities, the standard
methods for calculating light extinction coefficients on the basis of the Bouguer law lead to rough errors in estimation of
the optical quality of a material. 相似文献
186.
Z. R. Khasanova M. Yu. Vozhdaeva N. N. Kabal’nova E. A. Kantor 《Russian Journal of Applied Chemistry》2007,80(7):1105-1110
Products of the reaction of 1,2,4-trimethylbenzene with chlorine dioxide in aqueous solution were studied. A scheme of 1,2,4-trimethylbenzene transformations was suggested. The influence exerted on the number of the reaction products by the ClO2 dosage and time of its contact with the substrate was examined. 相似文献
187.
188.
S. E. Dizhur I. N. Kotel’nikov E. M. Dizhur 《Journal of Communications Technology and Electronics》2006,51(5):588-595
Al-δ-GaAs structures are studied where tunneling to one or more subbands of the 2D electron system of a near-surface delta-doped layer is observed. Reflection of electrons at the threshold of the emission of an LO-phonon is observed. This phenomenon occurs when a new subband is involved in the tunneling process and when intersubband transitions of the electrons in a 2D-system with the emission of an LO-phonon are added to the inelastic tunneling within a single subband. It is shown that, under the conditions of an intersubband polaron resonance, the reflection processes dominate during tunneling into the delta-layer. If, however, tunneling from the delta-layer occurs, the reflection processes are observed when two subbands are occupied. 相似文献
189.
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
190.
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