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31.
The photoreduction processes stimulated either the cw (power density 105–106 W/cm2) or pulsed (pulse energy 3–4 J, pulse duration 200 ns, effective laser spot diameter 1 mm) radiation of a CO2 laser on the surfaces of fused and crystalline quartz, as well as of natural silicates (nepheline KNa3[AlSiO4]4, rhodonite CaMn4[Si5O15], and zircon ZrSiO4), are studied. The X-ray emission analysis of irradiated surfaces showed that the laser irradiation of these materials leads
to the sublimation of silicon oxides and the enrichment of surfaces with constituent metal elements. Laser radiation also
stimulates the formation of silicon and metal nanoclusters on irradiated surfaces. The appearance of these nanoclusters is
confirmed by both photoluminescence and X-ray emission studies of irradiated surfaces. 相似文献
32.
We demonstrate that airborne light-absorbing particles can be photophoretically trapped and moved inside an optical lattice formed by multiple-beam interference. This technique allows simultaneous three-dimensional manipulation of multiple micro-objects in gases. 相似文献
33.
34.
Translated from Matematicheskie Zametki, Vol. 57, No. 1, pp. 133–137, January, 1995. 相似文献
35.
36.
A method for the synthesis of esters of -thiophenecarboxylic acids and diethyl 3-methyl-2,4-thiophenedicarboxylate by the deamination of derivatives of 2-amino-3-ethoxycarbonylthiophene has been proposed. Ethyl tetrahydrothionaphthene-3-carboxylate has been converted by dehydrogenation on heating with sulfur into ethyl thionaphthene-3-carboxylic acid. The corresponding acids have been obtained by the hydrolysis of the esters. A number of dialkylaminoalkyl esters has been obtained from -thiophenecarboxylic acids and 3-methyl-2, 4-thiophenedicarboxylic acid via the acid chlorides. 相似文献
37.
V. P. Shvedov A. A. Kopyrin V. S. Titov 《Journal of Radioanalytical and Nuclear Chemistry》1972,12(1):421-430
The effect of the composition and structure of higher tertiary amines on their efficiency in extracting nitric acid has been examined. The ionization constants of the amines in methanol have been determined by potentiometric titration. The extraction constants for nitric acid have been determined at constant ionic strength in the aqueous phase (μ=1). The dependence of these constants upon the concentrations and the degree of association of the amine salts in the organic phase has been examined. For the cases in which the role of steric factors is negligible it has been shown that at low amine salt concentrations in the organic phase there are quantitative regularities between the ionization constants of the amines in methanol, their extraction constants for nitric acid and the inductive effects of the substituents on the nitrogen atom. 相似文献
38.
V. I. Shvedov I. A. Kharizomenova N. V. Medvedeva A. N. Grinev 《Chemistry of Heterocyclic Compounds》1977,13(2):163-165
5-Tosylamino-2,3-dialkylthiophenes, which are alkylated to the corresponding 5-alkyl (tosyl)-amino derivatives, were synthesized from 2-amino-3-carbethoxy-4,5-dialkylthiophenes by tosylation and subsequent decarboxylation.See [1] for communication XV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 204–206, February, 1977. 相似文献
39.
V. I. Shvedov L. B. Altukhova N. P. Kostyuchenko A. N. Grinev 《Chemistry of Heterocyclic Compounds》1970,6(9):1162-1165
Reduction of 5, 6-dihydro-4H-pyrazino[1, 2, 3-lm]carbazole alkiodides with sodium in alcohol affords 3a, 4, 5, 6-tetrahydro-3H-pyrazino[1, 2, 3-lm]carbazoles, which are heterocyclic enamines. Some reactions of these compounds are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1244–1248, September, 1970. 相似文献
40.
V. I. Blynskii O. A. Bozhatkin E. S. Golub A. M. Lemeshevskaya S. V. Shvedov 《Journal of Applied Spectroscopy》2010,77(3):445-447
We examine the results of an effect of preliminary annealing on the spectral sensitivity of photodetectors in bipolar integrated
circuits, formed in silicon grown by the Czochralski method. We demonstrate the possibility of substantially improving the
sensitivity of photodetectors in the infrared region of the spectrum with twostep annealing. The observed effect is explained
by participation of oxidation in the gettering process, where oxidation precedes formation of a buried n+ layer in the substrate. 相似文献