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891.
Boric acid esters as thermal stabilizers and fungicidal additives for elastomers from natural rubber
New and previously synthesized boric acid esters were studied as thermal stabilizing and fungicidal additives to elastomers based on natural rubbers. 相似文献
892.
E. N. Chebotok V. Yu. Novikov I. N. Konovalova 《Russian Journal of Applied Chemistry》2006,79(7):1162-1166
Depolymerization of chitin and chitosan in the course of deacetylation in an alkaline medium was studied, and the influence exerted on the process by the nature and concentration of the alkali (NaOH, KOH) and salts (NaCl, NaI, KI) was examined. 相似文献
893.
S. V. Usachev A. S. Osipov G. I. Kostrykina T. I. Irkhina N. B. Tantsova E. G. Fedorova 《Russian Journal of Applied Chemistry》2006,79(11):1890-1895
Variation of the molecular structure characteristics and properties of natural and 1,4-cis-polybutadiene rubbers (gel content, molecular weight, degree of branching of macromolecules, viscosity) in the course of their separate and joint mastication in the presence of dibenzoylaminodiphenyl sulfide as mastication accelerator or without it was studied. 相似文献
894.
M. Mahjour-Shafiei H.R. Amir-Ahmadi J.C.S. Bacelar R. Castelijns K. Ermisch E.D. van Garderen I. Gašparić M.N. Harakeh N. Kalantar-Nayestanaki M. Kiš H. Löhner O. Scholten 《Physics letters. [Part B]》2006
A series of nucleon–nucleon bremsstrahlung (NNγ) experiments at 190 MeV incident beam energy have been performed at KVI in order to gain more insight into the dynamics governing the bremsstrahlung reaction. After initial measurements wherein the bremsstrahlung process was studied far away from the elastic limit, a new study was used to probe the process nearer to the elastic limit by measuring at lower photon energies. Measured cross sections and analyzing powers are compared with the predictions of a microscopic model and those of two soft-photon models. The theoretical calculations overestimate the data by up to ≈30%, for some kinematics. 相似文献
895.
896.
Conclusion The reaction of 1-arylsulfamido-2-chloroethanes with diethylamine and aniline gives 1-arylsulfamido-2-aminoethanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 943–946, April, 1987. 相似文献
897.
I. N. Flerov V. D. Fokina M. V. Gorev A. D. Vasiliev A. F. Bovina M. S. Molokeev A. G. Kocharova N. M. Laptash 《Physics of the Solid State》2006,48(4):759-764
Precision studies of the thermophysical properties and structure of an (NH4)2WO2F4 crystal have been performed. It was established reliably that there is a sequence of two phase transitions at T 1 = 201 K and T 2 = 160 K characterized by wedging out of an intermediate phase with an increase in pressure. The role of tetrahedral and octahedral ionic groups in the mechanism of the structural transitions was determined. 相似文献
898.
Z. U. Dzhabua T. O. Dadiani A. V. Gigineishvili M. Yu. Stamateli K. D. Davitadze G. N. Iluridze 《Physics of the Solid State》2006,48(8):1481-1485
A technique for preparing γ-Nd2S3 crystalline thin films through discrete vacuum thermal evaporation of a presynthesized bulk material is developed. The films deposited are doped with cadmium and lead. The reflectance and transmittance spectra of the films are measured in the photon energy range 0.2–3.0 eV at a temperature of 300 K. The frequency analysis of the absorption coefficient demonstrates that the γ-Nd2S3 films are characterized by an exponential absorption edge. The photoconductivity spectra and temperature dependences of the photoconductivity for the γ-Nd2S3 films doped with cadmium and lead are measured in the photon energy range 0.2–3.3 eV at temperatures varying from 115 to 380 K. The experimental data obtained are interpreted under the assumption that the acceptor levels formed by vacancies in the cation sublattice and compensated for by cadmium and lead donor dopants play a crucial role in the photoconduction. The ionization energy at the lead donor level is determined. 相似文献
899.
It is demonstrated that the diffraction of a plane light wave by an acoustic wave of fundamental frequency in the Raman-Nath
mode with admixture of the second acoustic harmonic may be accompanied by a considerable change in the higher diffraction
orders with numbers ±2, ±3, etc. Conditions for the selective suppression of the orders are obtained in the weak and strong
interaction modes. Results of a numerical simulation are presented. 相似文献
900.
A. N. Titov O. N. Suvorova S. Yu. Ketkov S. G. Titova A. I. Merentsov 《Physics of the Solid State》2006,48(8):1466-1471
Single crystals and polycrystals of titanium diselenide TiSe2 intercalated with ferrocene Fe(η5-C5H5)2 and cobaltocene Co(η5-C5H5)2 are synthesized. The magnetic susceptibility and electrical resistivity of the intercalation compounds are measured. The results obtained demonstrate that the intercalation brings about the formation of an impurity band with a temperature-dependent width. 相似文献