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1.
The general theory on the transformation of elastic waves at a rigid nodal junction of an arbitrary number of thin plates is considered. The notion of transformation marix is introduced, and a way for computing it and numerical examples are given. Properties of the transformation matrix resulted from the reciprocity principle and the energy conservatin law are studied. In particular, a new relation that expresses the energy conservation low for the case where a wave damped in the direction of the joint of plates is a source of a field is obtained. Bibliography: 18 titles. 相似文献
2.
3.
Lazareva T. G. Yakovleva O. V. Shinkareva E. V. 《Russian Journal of Applied Chemistry》2002,75(10):1692-1695
Rheological and electrical properties of polyvinyl alcohol solutions containing copper(II) and cobalt(II) chlorides are studied. Anomalous behavior of these properties is associated with complex formation, depending on the component ratio and temperature. 相似文献
4.
N. A. Yakovleva S. N. Klyamkin O. A. Veremeeva A. A. Tsikhotskaya 《Russian Chemical Bulletin》2005,54(1):135-140
Using heat conducting Tian—Calvet calorimetry and volumetric measurements, the first hydrogen absorption—desorption cycles in the LaNi5-H2 and CeNi5-H2 systems were studied. The pressure—composition isotherms were plotted, the equilibrium pressures of hydrogen along the absorption and desorption branches and in the region of hysteresis for different activation steps were determined, and the enthalpies of phase transitions α → β and β → α were calculated. The profiles of the heat evolution curves were analyzed. It was concluded that the mechanism of the reactions studied changes upon activation.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 134–139, January, 2005. 相似文献
5.
L.A. Isupova I.S. Yakovleva I.I. Gainutdinov Yu.T. Pavlyukhin V.A. Sadykov 《Reaction Kinetics and Catalysis Letters》2004,81(2):373-382
The phase composition and microstructure of samples of the La1-xCaxFeO3-y system prepared via a ceramic route were characterized by M?ssbauer spectroscopy. In all cases, iron was found in the 3+ state. The ordering
of anion vacancies in the samples with the composition in the range of 0.8 > x ≥ 0.4, which corresponds to a microheterogeneous
solid solution, generates new distorted octahedral and fivefold/tetrahedral sites revealed by two typical sextets. The disordering
of this solid solution and small (10-100 ?) sizes of domains with a perovskite, braunmillerite or Grenier phase structure
caused the appearance of a superparamagnetic doublet, which grows with the Ca content up to x = 0.8 but disappears in the
sample of pure braunmillerite. The appearance of Fe cations in a distorted coordination correlates with the increased activity
of the samples with a microheterogeneous structure in the CO catalytic oxidation and with their reducibility by H2.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
V. N. Odinokov G. Yu. Ishmuratov M. P. Yakovleva O. V. Sokol'skaya R. Ya. Kharisov É. P. Serebryakov G. A. Tolstikov 《Chemistry of Natural Compounds》1992,28(6):618-621
Starting from the readily available enantiomerically enriched (S)-(+)-3,7-dimethylocta-1,6-diene (ee ≃ 50%), we have synthesized
(4R)-4-methylnonan-1-ol — the sex pheromone of the yellow mealworm bettleTenebrio molitor L. A scheme for synthesizing the racemic analogue of the pheromone from 4-methyltetrahydropyran has been developed.
Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii,
No. 6, pp. 711–714, November–December, 1992. 相似文献
7.
N. V. Ivashkina E. A. Yakovleva I. D. Ivanchikova A. A. Moroz M. S. Shvartsberg 《Russian Chemical Bulletin》2005,54(6):1509-1513
Iodination of 5-amino- and 6-amino-1,4-naphthoquinones with I2 and HIO3 in aqueous dioxane occurs only at the benzoid ring. Depending on the reaction conditions, either aminoiodo- or aminodiiodonaphthoquinones
are produced. Diazotization of these compounds followed by reduction or replacement of the diazo group with iodine affords
mono- or polyiodo derivatives of 1,4-naphthoquinone.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1465–1469, June, 2005. 相似文献
8.
A. V. Yakovlev A. I. Finaenov S. L. Zabud’kov E. V. Yakovleva 《Russian Journal of Applied Chemistry》2006,79(11):1741-1751
Results obtained in synthesis of thermally expanded graphite by chemical and electrochemical methods with sulfuric and nitric acids are summarized. The possibility of controlling the properties of thermally expanded graphite compounds in electrochemical synthesis is demonstrated. The existing and promising application areas of thermally expanded graphite are analyzed. 相似文献
9.
V. N. Odinokov G. Yu. Ishmuratov M. P. Yakovleva O. V. Sokol'skaya R. Ya. Kharisov É. P. Serebryakov G. A. Tolstikov 《Chemistry of Natural Compounds》1993,28(6):618-621
Starting from the readily available enantiomerically enriched (S)-(+)-3,7-dimethylocta-1,6-diene (ee 50%), we have synthesized (4R)-4-methylnonan-1-ol — the sex pheromone of the yellow mealworm bettleTenebrio molitor L. A scheme for synthesizing the racemic analogue of the pheromone from 4-methyltetrahydropyran has been developed.Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 711–714, November–December, 1992. 相似文献
10.
G. Yu. Ishmuratov M. P. Yakovleva R. Ya. Kharisov G. I. Kunafina E. V. Gorobets A. V. Kuchin G. A. Tolstikov 《Russian Chemical Bulletin》1997,46(8):1465-1467
A convergent synthesis of octadeca-2E, 13Z-dienyl acetate, a pheromone component ofSynanthedon tipuliformis C., has been developed. The synthesis is based on cross-coupling of 8-iodooct-2E-en-I-ol THP ether with dec-5Z-enyl bromide catalyzed by CuBr.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1529–1531, August, 1997. 相似文献