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931.
G. S. Krinchik E. E. Chepurova I. M. Kuznetsova N. V. Pronina 《Russian Physics Journal》1989,32(11):871-874
We present results of magnetooptical investigations of bismuth-containing ferrite-garnet films with the easy axis of magnetization parallel to the specimen surface. Measurements were conducted for incident light with energies in the range 1.5–3.2 eV for transverse [equatorial Kerr effect (EKE)] and for longitudinal [meridional intensity effect (MIE)] magnetizations of thin-layer specimens. It is shown that the EKE differs from zero when the films are opaque, and it is established that the EKE peak in the region 2.8 eV increases with increasing bismuth concentration. For longitudinal magnetization, conditions for observing magnetooptical interference were realized. The experimental curves agree well with the theoretical ones.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 10–14, November, 1989. 相似文献
932.
The development of a breakdown wave in subthreshold HF fields is considered for the condition that the field energy density exceed the plasma energy density E2/4 > nT. It is shown that the breakdown wave propagation mechanism is controlled by HF diffusion with a coefficient iE2/4en. A model of breakdown development along the direction of the linear field polarization is constructed on the basis of this mechanism.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 55–60, August, 1989. 相似文献
933.
E. V. Petrova T. I. Izaak D. A. Filonenko A. P. Astashkina V. I. Otmakhov G. G. Volokitin 《Colloid Journal》2007,69(6):777-781
Peculiarities of the extraction of metal ions from aqueous solutions by fibrous polypropylene have been investigated. It has been found that metal ion adsorption proceeds owing to the existence of a gas-liquid-hydrophobic polymer boundary line. The process mechanism has been discussed. 相似文献
934.
935.
Procedures for separating products of the synthesis of ethylene oxide by two-column gas chromatography using both conventional capillary PLOT columns and packed capillary columns of a new type bearing microparticulated adsorbents are proposed. A combination of packed capillary columns with a microthermostat reduces both separation time and the size of the chromatographic system, which becomes compatible with microreactors. The short time of analysis enables the control over the work of a series of microreactors in a cyclic mode using one chromatographic system. 相似文献
936.
Yu. A. Yuzhelevskii E. G. Kagan V. N. Frolov A. L. Klebanskii 《Chemistry of Heterocyclic Compounds》1970,4(1):24-28
The influence of the number of 3, 3, 3-trifluoropropyl(methyl)siloxane links (/) in the cyclotetrasiloxanes mD4-m, where D represents the dimethylsiloxane link and m=0–4, on the rearrangement of these compounds in acetone solution under the action of sodium siloxanolate has been studied. The rearrangement takes place with the formation of a linear polysiloxane the degradation of which yields, in addition to the initial ring, cyclosiloxanes with a different structure. The rate of rearrangement of mD4-m and of the formation of a linear polysiloxane rises with an increase in m from 0 to 3. The equilibrium concentration of the linear polysiloxane formed from mD4-m is inversely proportional to m. Results have been obtained on the kinetics of the formation of the cyclosiloxanes mDn, where m=0–5, n=0–5, and m+n=3–6, in the rearrangement of the rings D3, 2D2, 3D, and 4. The reactivity of the siloxane links rises in the sequence (CH3)2Si-O-Si(CH3)2 < (CF3CH2CH2)-(CH3) Si-O-Si(CH3)2 <(CF3CH2CH2) (CH3)Si-O-Si(CH3) (CH2CH2CF3) . Because of the negative inductive effect transferred through the siloxane links, the 3, 3, 3-trifluoropropyl groups strongly activate the siloxane ring with respect to nucleophiiic reagents.For part I, see [3]. 相似文献
937.
E. Bujdosó 《Journal of Radioanalytical and Nuclear Chemistry》1993,174(1):187-198
938.
A. M. Zhizhaev E. N. Merkulova I. V. Bragin 《Russian Journal of Applied Chemistry》2007,80(10):1632-1635
Mechanism of interaction of copper sulfate with natural calcium carbonates, responsible for low residual copper concentrations in solutions and for the behavior of open and closed systems in storage is considered. 相似文献
939.
Ya. S. Yakhyaev S. N. Khadzhiev T. M. Gairbekov S. E. Spiridonov 《Reaction Kinetics and Catalysis Letters》1986,30(2):263-268
The effect of hydrothermal treatment of decationized superhigh-silica zeolite on the mechanism of n-hexane conversion has been studied. It has been established that thermosteam modification sharply decreases the cracking activity and increases the selectivity to aromatization reactions. Zeolite acidity markedly decreases, but its crystal structure does not become amorphous.
-. . .相似文献
940.
Th. Kappe E. Ziegler M. Ali A. Chirazi 《Monatshefte für Chemie / Chemical Monthly》1969,100(1):142-145
Zusammenfassung Perimidon (1) reagiert mit monosubstit. Malonsäure-trichlorphenylestern (2) bei 250° zu 9-Hydroxy-5,7-dioxo-4,5-dihydro-7H-pyrido[1,2,3-cd]perimidinen (3), die durch saure Hydrolyse zu 10-Amino-4-hydroxy-benzo[h]carbostyrilen (4) gespalten werden.
Syntheses of heterocycles, CXXII: Reaction of perimidone with reactive malonates
Perimidone (1) reacts with monosubstituted 2.4.6-trichlorophenyl malonates at 250° to 9-hydroxy-5.7-dioxo-4.5-dihydro-7H-pyrido[1.2.3-cd]perimidines (3), which are cleaved by acid yielding 10-amino-4-hydroxy-benzo[h]quinolin-2-ones (4).相似文献