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1.
The kinetics of the appearance of long-range order and the growth of antiphase domains (APD) in the alloy Au4Cr with the superstructure Dla in the ordered state are studied by x-ray diffraction methods. The features of the incubation period are investigated. It is established that ordering in the alloy Au4Cr occurs heterogeneously with the nucleation of well-ordered particles.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 98–105, December, 1991. 相似文献
2.
S. V. Starenchencko N. R. Sizonenko E. V. Kozlov 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(2):217-220
The kinetics of ordering of the Au4Zn alloy is investigated using X-ray diffractometry. It is established that the ordering and growth of domains inside the ordered phase are multistage processes. These processes are characterized by nucleation and growth of the ordered phase. The kinetics of growth of domains involves the nucleation and growth stages, as well as stages in which the crystal lattice axes have preferred or equally probable directions. The stages are more pronounced at low annealing temperatures. The duration of particular stages of the evolution of antiphase domains and their sizes depend on the annealing temperature. 相似文献
3.
4.
Igor V. Rzhepakovsky David A. Areshidze Svetlana S. Avanesyan Wolf D. Grimm Natalya V. Filatova Aleksander V. Kalinin Stanislav G. Kochergin Maria A. Kozlova Vladimir P. Kurchenko Marina N. Sizonenko Alexei A. Terentiev Lyudmila D. Timchenko Maria M. Trigub Andrey A. Nagdalian Sergei I. Piskov 《Molecules (Basel, Switzerland)》2022,27(3)
Chlorophytum genus has been extensively studied due to its diverse biological activities. We evaluated the methanolic extract of leaves of Chlorophytum comosum (Green type) (Thunb.) Jacques, the species that is less studied compared to C. borivilianum. The aim was to identify phytoconstituents of the methanolic extract of leaves of C. comosum and biological properties of its different fractions. Water fraction was analyzed with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Nineteen compounds belonging to different chemical classes were identified in the methanolic extract of leaves of C. comosum (Green type) (Thunb.) Jacques. In addition to several fatty acids, isoprenoid and steroid compounds were found among the most abundant constituents. One of the identified compounds, 4′-methylphenyl-1C-sulfonyl-β-d-galactoside, was not detected earlier in Chlorophytum extracts. The water fraction was toxic to HeLa cells but not to Vero cells. Our data demonstrate that methanolic extract of leaves of C. comosum can be a valuable source of bioactive constituents. The water fraction of the extract exhibited promising antitumor potential based on a high ratio of HeLa vs. Vero cytotoxicity. 相似文献
5.
Local as well as surface waves excited in a streamingless plasma are investigated. In addition to the gradient instabilities of an isothermal plasma now branches of a convective type are found in plasmas with a hot electron componentZ T
e
T
i
. Both their frequencies and growth rates may exceed the ion cyclotron frequency, >
Bi
even if the effect of the finite ion Larmor radius is negligible. Then the surface waves may become of enhanced importance. We compare, therefore, the conditions for excitation and the growth rates of the surface waves with those of the short wavelength (local) perturbations. Upper estimates of the saturated wave amplitudes are also given. For a special profile of the plasma density the problem is solved analytically also in the plasma boundary layer.On leave of absence from the Physical and Technical Institute, Kharkov, U.S.S.R. 相似文献
6.
Rassukanaya Yu. V. Sizonenko Ya. A. Sinitsa A. A. Boiko V. I. Podoprigorina A. A. Onys'ko P. P. 《Russian Journal of General Chemistry》2002,72(11):1695-1698
N-(Trichloroacetyl)trichloroacetylimidoyl chloride reacts with trialkyl phosphites with substitution of the imidoyl chlorine atom and formation of C-phosphorylated heterodienes. The reaction with triphenyl phosphite or o-phenylene diethylphosphoroamidite proceeds as [4+1]-cycloaddition to give mono- or spirocyclic oxazaphospholines with the five-coordinate phosphorus atom. Dialkyl or diphenyl hydrogen phosphites add across the C = N bond of imidoyl chloride to give labile N-(-phosphorylated) trichloroacetamides. 相似文献
7.
N. A. Koneva N. A. Popova E. L. Nikonenko N. R. Sizonenko 《Bulletin of the Russian Academy of Sciences: Physics》2018,82(7):769-772
Changes in the structural and phase state of low-carbon steel with a mixed structure of tempered martensite and ferrite, and deformed by equal channel angular pressing (ECAP), are analyzed by means of transmission electronic microscopy and X-ray diffraction. The impact ECAP has on the phase composition and morphology of the alloy is determined. The behavior of the carbide phase is studied. Grain misorientations are measured. Special attention is given to the problem of fine grain formation upon ECAP. 相似文献
8.
Koneva N. A. Lokotko E. Yu Trishkina L. I. Piskalenko V. V. Gromov V. E. Sizonenko N. R. 《Russian Physics Journal》2002,45(3):232-241
The evolution of the phase content and morphology and crystalline defects during temperature and pressure cycling is studied by the methods of transmission electron microscopy and x-ray diffraction analysis. Thermostable Fe–0.12C–1Cr–1Mo–1V steel in the initial ferrite-pearlite state is examined. The evolution of the grain structure and dislocation density is quantitatively described. A low stability of large pearlite grains at temperatures above 600°C is established. The problem of oxidizing of steel of this class is also discussed. 相似文献
9.
We have used x-ray analysis to study the disordering and decomposition processes in Au4Zn alloys which exhibit a long-period Ll2(MM) superstructure at low temperatures. Several stages are observed during isothermal anneals of the alloy above Tc: I) disordering; II) an incubation period; and III) decomposition. The duration of each of these stages depends on the annealing
temperature. It is shown that the disordering of the Ll2(MM) superstructure always precedes the decomposition process, but the short-range order in the disordered solid solution
resembles that of the Ll2(MM) long-range order.
State University of Architecture and Construction, Tomsk. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika,
No. 8, pp. 56–62, August, 1997. 相似文献
10.
Nonlinear effects stabilizing the convective instabilities excited in an anisothermic plasma (T
etT
i) at the plasma boundaryaVs/
Bi) are discussed. Waves having in the linear theory (Part I) the highest growth rates (
Bi) saturate at first. Being excited by a small part of slow plasma electrons (
zTe) only, they saturate at a relatively low level. Further, surface waves with lower frequencies and higher phase velocities (
ph/kz) become dominant and a broadening of the plasma boundary occurs. For their saturation nonlinear interaction is more important than the quasilinear effects. During the time interval of several
Bi
–1
the longest surface waves withk
yBi/Vs, BikyVs and
ph
Te
saturate at the absolutely highest level. The plasma boundary broadens in the meanwhile up toaV
s/Bi. The wave energy is comparable to the whole energy connected with the longitudinal motion of the initially thermal electrons inside this boundary layer. The wave amplitude is large enough to trap the initially cold ions belonging to this layer and heat them up to energies comparable to those of the electron component. The heating process occurs again within several
Bi
–1
and the Larmor radius of the ions is then comparable toV
s/Bi. Further evolution of the system is governed by the unstable local perturbations.He leaves of absence from thePhysical and Technical Institute, Kharkov, USSR. 相似文献