The stream structure of the solar supercorona

The scattering properties of the solar-wind plasma in the region of a subsonic flow at the distances R(10–16)R from the Sun were studied by the radio occultation method in 1988–92. The long-term dynamics of the large-scale structure of solar wind in this region is similar to the well-known variations of the corona observed in optics. The generality of long-term evolution in the stream structure of flows at different distances from the Sun indicates the existence of a single mechanism of acceleration of the large-scale flows giving rise to solar wind.Institute of Geomagnetism, the lonosphere, and Radio-Wave Propagation, Russian Academy of Sciences, Troitsk, Moscow region; P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow; Radiophysical Research Institute, Niznhy Novogorod. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, No. 9, pp. 920–925, September, 1995.     

Unidirectional anisotropy of the velocity of domain walls in ferrite-garnet films

A mechanism to explain the gigantic unidirectional anisotropy of the velocity of domain walls, which includes the local rotation of the magnetization in front of a moving domain wall, initiated by radiated spin waves is proposed. Institute of General Physics, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 45–48, September, 1997.     

Dissociation of water by microwave radiation

The hydrogen-peroxide concentrations c(H₂O₂) in water irradiated by electromagnetic energy at frequencies of 2500 MHz and 10000 MHz are measured by means of chemiluminescence. It is concluded that water dissociation into H and OH groups is a part of the mechanism of microwave-radiation absorption.Institute of Applied Physics, Russian Academy of Sciences. Institute of Organometallic Chemistry, Russian Academy of Sciences. Translated from izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 37, No. 1, pp. 149–154, January, 1994.     

Physics of the plasticity and fracture of high-strength crystals

Systematic studies of the mechanism of plastic deformation, strain hardening, and fracture of high-strength single crystals of heterophase alloys based on copper and austenitic stainless steels with nitrogen are reported. It is shown that the attainment of high resistance to the motion of dislocations results in the appearance of new mechanical behavior: strong orientation dependence of the critical shear stresses, a change in the deformation mechanism from slip to twinning, loss of mechanical flow stability at early stages in deformation, and a transition from viscous to brittle fracture.V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 3–24, September, 1992.     

A b initio calculation of the growth of Te nanorods and Bi2Te3 nanoplatelets

In this paper the growth mechanism of a Te/Bi2Te3 novel structure is studied by ab-initio calculations. The results show that the growth of Te nanorods is determined by the adsorption energy of Te atoms on different crystalline Te surfaces. The adsorption energy of Te on the Te （001） surface is 3.29 eV, which is about 0.25 eV higher than that of Te on the Te （110）. This energy difference makes the preferential growth direction along the 〈 001 〉 direction. In addition, the higher surface energy of Bi2Te3 （110） and the lattice misfit between crystalline Bi2We3 and Te along 〈 001 〉 direction are considered to explain the growth of the Bi2Te3 nanoplatelets, in which Volmer-Weber model is used. The theoretical results are in agreement with experimental observation.     

Combined mechanism for the hardening of a ZrO2-Y2O3 ceramic

The phase composition and mechanical properties have been examined for a ZrO₂-Y₂O₃ ceramic having a combined hardening mechanism, which was made by high-temperature sintering under vacuum. The mechanism enables one to alter the properties of the zirconium dioxide base ceramic substantially. The material has a combination of high strength and toughness because of the high viscosity of the untransformed part of the material, which produces an additional strengthening effect along with the transformational hardening.Institute for Strength Physics and Materials Science, Siberian Division, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavednii, Fizika, No. 8, pp. 89–95, August, 1994.     

Superconductivity in the metastable phases of transition metal hydrides

New inelastic neutron scattering data and the observation of an inverse isotope effect in metastable phases of titanium hydride give support for the realization of the recently proposed anharmonic (two-level systems mediated) mechanism of superconductivity in the hydrides of titanium, hafnium and zirconium. The model allows in combination with an optical phonon contribution to explain not only theT _c enhancement but also the change of the sign of the isotope effect experimentally observed for PdMH (M=Cu, Ag, Au) alloys.On leave from Institute of Physics & Technology Ulaanbaatar-51 Mongolia     

Study of the Elementary Growth Processes During Vapor-Phase Epitaxy of Semiconducting III–V Compounds

A review of studies performed at the V. D. Kuznetsov Siberian Physical-Technical Institute at Tomsk State University and aimed at obtaining detailed information on the elementary growth processes proceeding at the crystallization front during vapor-phase epitaxy of semiconducting III–V compound films is presented in the paper. The general approach to the problem and methods of its solution are described. Results of investigations of the adsorption layer composition, surface diffusion processes, and incorporation of growth components into a crystal are presented. The mechanism of epitaxial layer growth in semiconducting III–V compounds is discussed.     

Features of evolution of the substructure in the creep of dispersion-hardened nickel

A study is made of the laws governing high-temperature creep and the evolution of the substructure in dispersion-hardened alloy Ni — 3 vol. % HfO₂ during its free annealing and creep. The polygonized substructure was formed in the alloy prior to annealing. An analysis is made of structural transformations at different structural levels and the mechanism of high-temperature creep in the alloy. Institute of the Physics of Strength and Materials Science, Siberian Branch of the Russian Academy of Sciences. All-Republic Engineering-Technical Center, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 83–89, March, 1998.     

Mechanism of the motion of domain walls with spin wave radiation in uniaxial magnetic films

It is shown, using the example of epitaxial ferrite—garnet films with (111) orientation whose dimensionless damping parameter was varied over a wide range, that for uniaxial magnetic films the mechanism of the motion of the domain walls is universal and includes local rotation of the magnetization ahead of the moving domain wall. The threshold field for the transition to this mechanism of motion of the domain walls is proportional to the uniaxial magnetic anisotropy field. On the curve of the dependence of the domain wall velocity on the acting magnetic field, this mechanism corresponds to the section with increased differential mobility of the domain walls. Magnitooptoelktronika Joint Self-Financing Laboratory, N. R. Ogarev Institute of General Physics, Russian Academy of Sciences, Mordovian State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 9–14, July, 1997.     

A study of the Co59(p,n) reaction atE p =5·75–6·39 MeV

In this paper the angular distribution of neutrons from the reaction Co⁵⁹(p, n) Ni⁵⁹ was measured for six energies of the protonE _p lying in an interval between 5·75 and 6·39 MeV. The analysis of these results showed that other mechanisms besides the compound nucleus mechanism play a role in the whole studied region ofE _p . Neither their relative contribution nor the exact mechanism were determined.The authors would like to express their gratitude to Prof. Dr. V. Petrílka for his constant interest in this experiment and to Mr. Kemének from the Nuclear Research Institute of the Czechoslovak Academy of Sciences for the calculation of the coefficients in Table I. We are also indebted to the entire cyclotron team of the Nuclear Research Institute for their perfect cooperation during the measurements and to a group of physicists of this department for having put at our disposal the majority of the apparatus used.     

Formation of the surface layer structure of electron-beam-doped steel

We demonstrate the possibility of strengthening the surface layer of steel through the mechanism of irradiation with a relativistic electron beam by precipitating the high-strength carboboride inclusions in the solid martensitic matrix. The hardness in the processed region depends on its composition and the thickness of the previously deposited powder coating. The introduction of special modifying admixtures significantly reduces in size the structure of the layer.Institute of Strength Physics and Materials Science, Siberian Branch, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 89–94, April, 1994.     

Asymptotically free grand-unification theories and moleholes

The asymptotic form of the effective action in asymptotically free grand-unification theories in a curved space is analyzed. This asymptotic form may prove useful in a mechanism for zeroing the cosmological constant on the basis of moleholes. Tomsk Pedagogical Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 54–56, February, 1993.     

Activation energy for diffusion of point defects at the surfaces of F.C.C. metals

The energies for migration of vacancies and adatoms and the adatom formation energy at surfaces with low indices have been calculated for aluminum, nickel, copper, palladium, silver, platinum, and gold using the inserted atom method. We have found the self-diffusion activation energies for the jumpwise diffusion mechanism with participation of both types of surface point defect. V. D. Kuznetsov Siberian Physicotechnical Institute at Tomsk University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii. Fizika, No. 6, pp. 89–96, June, 1997.     

Comparison of the efficiency of the deflection of proton beams with various energies by a bent crystal with the use of planar channeling and the stochastic deflection mechanism

The efficiency of the deflection of 50-, 15-, and 1.3-GeV proton beams by means of planar channeling in a bent silicon crystal has been compared to that by means of the stochastic mechanism of the deflection of charged particles by the bent crystal. The deflection of protons at single passage through the crystal has been simulated. The results of the experiment on the deflection of a circulating beam at the U-70 accelerator (Institute for High Energy Physics, Protvino, Moscow region) are presented. It has been shown that the efficiency of the stochastic deflection mechanism increases with a decrease in the energy, whereas the efficiency of the planar channeling for deflection decreases.     

Effect of emission center density on the rate of degradation processes in thin-film MIM cathodes

The effect of the density of emission centers on the rate of degradation of these centers is studied for MIM systems with different materials of the upper electrode. It is shown that the degradation rate decreases sharply with increasing density of the emission centers. The obtained result is described by using the concepts about the nature of electronic moulding and the degradation mechanism of emission centers.Institute of Automatic Control Systems and Radioelectronics, Tomsk. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 95–98, June, 1992.     

Influence of deviation from stoichiometry on the plasticity and mechanism of fracture of the boron-alloyed intermetallic compound Ni3Al obtained by self-propagating high-temperature synthesis

We have studied the effect that deviation of the composition of an ally from stoichiometry has on the plasticity , strength _B, and the fracture mechanism of the intermetallic compound Ni₃Al obtained by self-propagating high-temperature synthesis. The variation of the tensile strength, plasticity, type of fracture, and the cohesive strength _coh of grains have been show to be correlated. The cohesive strength increases with the Al content in the alloy, most rapidly up to 24.0 at. % Al.V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Institute of Strength Physics and Materials Science, Siberian Branch, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 104–110, April, 1994.     

Influence of defects on the systematics of internal oxidation in carbide-strengthened molybdenum alloys

We have studied the kinetics and mechanism of low-temperature internal oxidation in the rolling-deformed molybdenum alloy TSM-4. We find a significant increase in the growth rate of the thickness of the internally oxidized zone above the theoretically predicted parabolic time dependence. We have performed studies to elucidate the reasons for this phenomenon. We show that low-temperature internal oxidation of a substructure-strengthened TSM-4 alloy is an effective way of increasing its high-temperature strength.V. D. Kuznetsov Physicotechnical Institute, Tomsk State University, Siberia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 87–95, May, 1993.     

Intrinsic and extrinsic vortex nucleation mechanisms in the flow

We propose very general vortex nucleation mechanisms[1] analogous to a hydrodynamic instability and calculate associated critical velocity in agreement with experiments. The creation of vortices via extrinsic mechanism is driven by a formation of the surface vorticity sheet created by the flow, which reaches a critical size. Such a sheet screens an attraction of a half-vortex ring to the wall, the barrier for the vortex nucleation disappears and the vortex nucleation is started. In the intrinsic mechanism the creation of a big vortex ring, which transforms into the vortex, is driven by a fluctuative generation of small vortex rings. Work supported by NORDITA and Landau Institute     

Autowave processes in stage i easy glide in the flow curve for single crystals

A material under loading is treated as a dissipative bistable medium described by a nonlinear equation of the reaction-diffusion type for order parameters. The coefficients of the equation are temperature and stress dependent. It is shown that in the easy glide stage I deformation the plastic flow occurs by the switching wave propagation mechanism. The action of the temperature on the critical shear stress and on the length of the region of easy glide under quasi-static loading is analyzed. Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 8–13, June, 1999.