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71.
Popova N. A. Sosnin O. V. Ignatenko L. N. Konovalov S. V. Kovalenko V. V. Ivanov Yu. F. Gromov V. E. Koneva N. A. 《Russian Physics Journal》2002,45(3):319-328
The methods of transmission electron microscopy are used to investigate the structure and phase content of Fe–0.45C–17Mn–3Al steel subjected to multicyclic fatigue tests to failure after intermediate electrostimulation. It is demonstrated that electrostimulation does not change the mechanism of steel failure. An increase in the operating life time of samples after electrostimulation in the intermediate test stage is connected with the hindered -martensitic transformation, the relaxation of stress concentrators, and the reduction of the volume fraction of the critical dislocation (network) substructure in which -martensite is mainly developed. 相似文献
72.
G. Ya. Popova T. V. Andrushkevich G. A. Zenkovets L. M. Plyasova N. V. Grebenyuk 《Reaction Kinetics and Catalysis Letters》1990,41(1):21-25
Catalytic properties of V-Sb-O systems in acrolein oxidation have been studied. It has been established that the changes in the activity and selectivity of the catalysts are due to the phase and chemical properties of the system.
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73.
M. A. Krivov E. V. Malisova É. N. Mel'chenko M. P. Nikiforova E. A. Popova L. K. Tarasova S. S. Khludkov 《Russian Physics Journal》1977,20(10):1333-1337
The distribution of the electrophysical and photoelectric properties of diffuse layers of p-GaAs obtained by doping copper using different diffusion modes is investigated. The properties of diffuse layers of p — n structures and volume specimens doped with copper over the whole depth are compared. The behavior of impurity centers is studied in these specimens and their effect on the electrophysical and photoelectric parameters of the material is investigated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 95–100, October, 1977.In conclusion we thank I. V. Kamenskii for carrying out the experiments. 相似文献
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78.
É. A. Zvezdina V. V. Derbenev V. A. Bren A. N. Popova G. N. Dorofeenko 《Chemistry of Heterocyclic Compounds》1976,12(8):847-850
On the basis of the measured basicity constants of pyrylium and pyridinium salts containing p-aminophenyl substituents it is shown that the positive charge in the pyrylium cation is considerably higher than in the pyridinium cation. The constants of the pyrylium and pyridinium substituents, which show that the magnitude of the electronic effect of the pyrylium ring is considerably higher than that of the pyrydinium ring, were calculated. The reaction of the indicated pyrylium salts with some electrophilic and nucleophilic reagents was examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1025–1028, August, 1976. 相似文献
79.
The temperature dependences of the molar heat capacity at constant pressure, Cp, of Pb5(Ge1?xSix)3O11 crystals with x=0, 0.39, and 0.45 in the range 5–300 K, as well as of their permittivity, dielectric losses, and the pyroelectric effect, have been measured. Experimental data on the temperature behavior of the heat capacity are presented in the form of a sum of two Debye and one Einstein terms, Cp(T)=0.405CD1(ΘD1=160 K, T)+0.53CD2(ΘD2=750 K, T)+0.046CE(ΘE=47 K, T). Besides a peak in the region of the ferroelectric Curie point Tc=450 K for crystals with x=0, the temperature dependences of the heat capacity did not reveal any other pronounced anomalies. 相似文献
80.
N. A. Koneva N. A. Popova E. V. Kozlov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(5):666-669
The role of the size effect in the formation of defect structures in metallic materials was studied experimentally. The objects
of study were ultrafine grain (UFG) copper, nickel, and martensitic steel. The effect of the size of grains and fragments
on the scalar density of dislocation and the density of partial disclinations was studied by means of transmission electron
microscopy (TEM). Measurements were performed for the 100–500 nm range of grain and fragment sizes. Similarities was found
in the behavior of grain and fragmented structures. 相似文献