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201.
The results of the oxidation of carbon nanofibers and materials obtained on their basis are presented; these results demonstrate that the nanofibers were formed by carbon with different degrees of crystal structure ordering. The experimental data supported previous hypotheses that amorphous carbon results from the decomposition of metal carbides. The subsequent formation of spatial structures and the appearance of crystalline carbon species resulted from catalytic graphitization. It was demonstrated that sorbents can be prepared based on carbon nanofibers after pyrolytic consolidation followed by activation, and these sorbents are more effective than well-known sorbents. 相似文献
202.
I. I. Nemets Yu. N. Trepalina E. A. Doroganov 《Refractories and Industrial Ceramics》2008,49(3):205-208
Physicotechnical properties are provided for concretes based on mechanically-activated phosphate suspensions previously modified
with magnesium and aluminum hydroxides and silicic acid. The results obtained demonstrate the efficiency of using modifying
additions in order to increase the strength and heat resistance of corundum concretes.
Translated from Novye Ogneupory, No. 5, pp. 32–35, May 2008. 相似文献
203.
I. V. Smirnov 《Automatic Documentation and Mathematical Linguistics》2007,41(3):108-113
The task of ascertaining minimal semantic-syntactic text units within the framework of the task of the semantic analysis of texts in the Russian language is considered. The use of the DSM-method for producing rules for ascertaining the meanings of syntaxemes is described, the setting of the goal of producing rules in DSM-method terminology is presented. The analysis of the results of computer experiments and the causes of the presence of contradictory rules are given. 相似文献
204.
A high-power and high-repetition-rate passively Q -switched ytterbium-doped single-mode double-clad fiber laser was built using a Cr4+:YAG saturable absorber (SA). Two different SAs with initial transmissions of Tomicron = 30% and Tomicron = 50% were studied. At the maximum coupled pump power of 9.8 W, an output power of 4.7 W, pulse duration of 143 ns, pulse repetition rate of 253 KHz, pulse energy of 18.5 muJ, and slope efficiency of 49% were obtained with the Tomicron = 30% SA. 相似文献
205.
Folds on the temperature surfaces of heterogeneous multicomponent liquid-vapor systems 总被引:1,自引:1,他引:0
Regularities in the behavior of folds on the surface of equilibrium temperatures for multicomponent two-phase mixtures are studied. The concept of the multiplicity of a fold on the surface of temperatures is introduced. 相似文献
206.
M.P. Gaukroger P.M. Martineau M.J. Crowder I. Friel S.D. Williams D.J. Twitchen 《Diamond and Related Materials》2008,17(3):262-269
X-ray topography has been used to study single crystal diamond samples homoepitaxially grown by microwave plasma-assisted chemical vapour deposition (CVD) on high pressure high temperature (HPHT) and CVD synthetic diamond substrates. Clusters of dislocations in the CVD diamond layers emanated from points at or near the interface with the substrate. The Burgers vectors of observed dislocations have been determined from sets of {111} projection topographs. Dislocations have line directions close to the [001] growth direction and are either edge or 45° mixed dislocations. Where groups of dislocations originated at isolated points they tended to be of the edge variety. Where the substrate surface was deliberately damaged before growth, two sets of dislocations were observed to have propagated from each line of damage and there was a tendency for dislocations to be of the 45° mixed variety with a component of their Burgers vector parallel to the polishing direction. It is demonstrated that X-ray topography can be used to deduce the growth history of CVD synthetic diamond samples produced in multiple growth stages. 相似文献
207.
L. A. Kosyachenko I. M. Rarenko E. F. Sklyarchuk I. I. German Sun Weiguo 《Semiconductors》2006,40(5):554-557
Photodiodes designed to be sensitive in the region 0.5–1.7 μm and obtained by vacuum magnetron sputtering of the ITO (SnO2 + In2O3) layer on the surface of the Hg3In2Te6 single crystal are studied. The electrical characteristics, measured at 265–333 K, indicate that the mechanism of charge
transport in the diodes under study is thermionic. The current-voltage characteristic and its temperature variations are described
quantitatively based on the energy diagram and the found parameters of the heterojunction.
Original Russian Text ? L.A. Kosyachenko, I.M. Rarenko, E.F. Sklyarchuk, I.I. German, Sun Weiguo, 2006, published in Fizika
i Tekhnika Poluprovodnikov, 2006, Vol. 40, No. 5, pp. 568–571. 相似文献
208.
M. M. Zverev N. A. Gamov D. V. Peregoudov V. B. Studionov E. V. Zdanova I. V. Sedova S. V. Gronin S. V. Sorokin S. V. Ivanov P. S. Kop’ev 《Semiconductors》2008,42(12):1440-1444
Emission characteristics of an electron-beam-pumped Cd(Zn)Se/ZnMgSSe semiconductor laser are studied. The laser’s active region consists of a set of ten equidistant ZnSe quantum wells containing fractional-monolayer CdSe quantum-dot inserts and a waveguide formed by a short-period superlattice with the net thickness of ~0.65 μm. Lasing occurs at room temperature at a wavelength of 542 nm. Pulsed power as high as 12 W per cavity face and an unprecedentedly high efficiency of ~8.5% are attained for the electron-beam energy of 23 keV. 相似文献
209.
M. I. Mazurkov V. S. Dmitrenko S. N. Kropachev 《Radioelectronics and Communications Systems》2008,51(2):106-111
It is proposed a rule of total classes of composition systems of discrete frequency signals (CDF-signals) construction in extended Galois fields. It is carried out modeling and research a correlation properties of CDF-signals, and determined their practical attraction. 相似文献
210.