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921.
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
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926.
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
927.
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
928.
Four relaxation processes and one ferroelectric-paraelectric phase transition are revealed in vinylidene fluoride-hexafluoropropylene copolymers with different ratios of the components in the temperature range from ?100 to 150°C. The relaxation process occurring at the lowest temperature is associated with the local mobility of the chains, whereas the relaxation process at a higher temperature is due to micro-Brownian motion of segments in the amorphous phase in the glass transition range. A smeared relaxor phase transition from the polar modification of the α phase of vinylidene fluoride units to the paraelectric phase is observed in the temperature range 50–70°C. At higher temperatures, there occurs an intensive relaxation process that can be attributed to space-charge relaxation or manifestation of the normal relaxation mode. 相似文献
929.
N. V. Khitrich I. I. Seifullina Yu. K. Epimakhov P. A. Ivanchenko 《Russian Journal of Applied Chemistry》2006,79(9):1514-1517
Kinetic features of radical polymerization of styrene initiated by tert-butyl perbenzoate in the presence of tris(N,N-dimethyldithiocarbamato)cobalt(III) (CoL3) and its adduct with iodine (CoL3 · 2I2) were studied. The optimal concentration ratios of the activators and tert-butyl perbenzoate, providing fast styrene polymerization at 338–368 K, were determined. 相似文献
930.
E. V. Gavryushin T. I. Gorbunova A. Ya. Zapevalov V. I. Saloutin 《Russian Journal of Applied Chemistry》2006,79(5):861-864
Wetting angles and limits of thermal stability of esters derived from pentaerythritol and perfluoro-, ω-chloropolyfluoro-, and perfluoropolyethercarboxylic acids were studied. 相似文献