排序方式: 共有52条查询结果,搜索用时 218 毫秒
1.
Roginskaya Yu. E. Lubnin E. N. Safonova T. Ya. Chuvilin A. L. Politova E. D. Tsirlina G. A. 《Russian Journal of Electrochemistry》2003,39(3):253-262
The peculiarities of bulk and surface structures of electrolytic palladium deposits formed under hydride formation conditions are studied by x-ray diffraction (XRD) and x-ray photoelectron spectroscopy techniques. For anomalous deposits with high hydrogen capacities, the evolution of the XRD behavior is traced as a function of thermal treatment. The material is shown to comprise two cubic phases with different lattice parameters. 相似文献
2.
O. B. Pavlova-Verevkina L. A. Ozerina E. D. Politova N. M. Surin A. N. Ozerin 《Colloid Journal》2009,71(4):529-533
We studied the slow aggregation of dilute TiO2 hydrosols containing narrow fractions of nanocrystals separated from polydisperse sol by the stepwise coagulation with portions of HCl. It is shown that the kinetics of this process and the structure of formed aggregates greatly depend on the ionic strength and the pH of a medium. It is suggested that, in the presence of various electrolytes, the aggregation proceeds by an identical mechanism. In this case, highly ordered aggregates are formed in which there are thin layers of medium between TiO2 nanocrystals. 相似文献
3.
Yu. E. Roginskaya A. D. Shepelev T. Kh. Tenchurin E. D. Politova B. A. Loginov N. V. Kozlova T. L. Kulova A. M. Skundin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(11):2013-2019
Composite polymer fibers with a composition of Si-C-O obtained by electrospinning of precursors solution containing polycarbosilane
or phenol formaldehyde resins with an admix of organic-silicon compounds were synthesized in order to find efficient new electrode
materials for lithium ion batteries. The composition and structure of pyrolized composite fibers were studied by means of
X-ray dispersive analysis and X-ray diffraction, Raman spectroscopy, and by AFM and SEM. It was shown that the composite fibers
(with a diameter of 0.5–1.5 μm) were nanostructured materials with carbon and silicon-oxy-carbide areas about 2–5 nm in size.
A model of the nanostructure of a skeleton for composite fibers synthesized is proposed. 相似文献
4.
Smolyanskii A. S. Arsentyev M. A. Rashkovskii A. Yu. Politova E. D. 《Crystallography Reports》2019,64(4):553-558
Crystallography Reports - An analysis of the diffraction patterns of powdered polytetrafluoroethylene (PTFE) γ-irradiated at room temperature in a nitrogen atmosphere to doses of 10–500... 相似文献
5.
G. S. Burkhanov V. B. Chzhan G. A. Politova J. Cwik N. B. Kolchugina I. S. Tereshina 《Doklady Physics》2016,61(4):168-171
With the use of sublimed dysprosium having a controllable impurity composition, two physical functional phenomena induced by a magnetic field are studied: magnetostriction and the magnetocaloric effect, which is estimated by independent direct and indirect methods. A giant magnetostriction value at the “order–order” magnetic phase transition and a large magnetocaloric effect in high magnetic fields at the “order–disorder” transition are shown. Both phenomena are discussed in relation to the complex field and temperature behavior of metallic-dysprosium magnetization, the measurement of which is carried out in wide intervals of temperature and magnetic fields (to 14 T). 相似文献
6.
G. S. Burkhanov I. S. Tereshina G. A. Politova I. A. Pelevin Yu. S. Koshkidko M. A. Paukov H. Drulis 《Doklady Physics》2017,62(1):10-13
The nature of the magnetocaloric effect (MCE) in compounds R2Fe14B (R = Nd, Er) and their hydrides in a wide temperature range is investigated. The investigation is carried out on initial samples of a special purity including single-crystalline ones. The highest value of the magnetocaloric effect is established in the Curie-temperature region. The hydrogenation of samples affects the value of the MCE. The model explaining the dependence of the value and sign of the magnetocaloric effect on the hydrogen contents in R2Fe14B compounds with participation of erbium and neodymium is proposed. 相似文献
7.
G. A. Politova G. S. Burkhanov I. S. Tereshina T. P. Kaminskaya V. B. Chzhan E. A. Tereshina 《Technical Physics》2017,62(4):577-582
A comprehensive analysis of the structure, phase composition, surface topology features, and magnetic and magnetocaloric properties of Tb0.3Dy0.35Ho0.35Co1.75 T 0.25 (T = Al, Fe) multicomponent alloys has been performed. The specifics of variations in the structure and functional properties induced by the partial substitution of cobalt atoms in the 3d sublattice of RCo2 with aluminum or iron atoms have been determined. 相似文献
8.
E.?D.?Politova E.?A.?Fortal’nova G.?M.?Kaleva A.?V.?Mosunov L.?I.?Andronova S.?A.?Andropova M.?G.?Safronenko N.?U.?Venskovski? 《Physics of the Solid State》2009,51(7):1443-1448
Ceramic solid solutions (Bi1 ? x La x )4V2O11 ? z (I), Bi4(V1 ? x Fe x )2O11 ? y (II), and (Bi1 ? x La x )4(V0.96Fe0.04)2O11 ? y (III) (x = 0–0.3, step Δx = 0.02) are prepared using solid-phase synthesis. The concentration and temperature ranges of stabilization of different polymorphic modifications, including the ranges of concentrations x corresponding to the stabilization of the ferroelectric phase, are established. It is revealed that an increase in the concentration x in the region of existence of the pseudoorthorhombic phase α of the solid solutions studied leads to a decrease in the transition temperature, smearing of the transition, and an increase in the width of the thermal hysteresis of the ferroelectric phase transition. The effect of compressing of the domain walls by oxygen vacancies was revealed in the samples from the region of existence of the ferroelectric α phase, and the effect of dielectric relaxation was detected in the samples from the region of existence of the orthorhombic phase β. 相似文献
9.
I. S. Tereshina S. A. Nikitin G. A. Politova A. A. Opalenko E. A. Tereshina I. V. Telegina 《Physics of the Solid State》2009,51(1):92-98
The compounds Tb0.35Dy0.45Er0.2Fe2 − x
Co
x
(0 ≤ x ≤ 2) are synthesized in both polycrystalline and single-crystal states. The composition of the new multicomponent alloys
with compensated magnetic anisotropy is calculated in the framework of the single-ion magnetic anisotropy model with allowance
for the data on the temperature dependences of the magnetic anisotropy constants for RFe2 single crystals. The synthesized compounds are characterized using metallographic, chemical, X-ray diffraction, and thermomagnetic
methods. A combined analysis of the magnetic and magnetoelastic properties is also carried out. It is established that the
high magnetostriction characteristics of the rare-earth intermetallic compounds Tb0.35Dy0.45Er0.2Fe2 − x
Co
x
with a structure of Laves phases are observed in the region of the spin-reorientational phase transition whose temperature
can be varied by properly choosing the Co content. It is found that, in the room-temperature region, the magnetic susceptibility
(dλ/dH) of the composition with x = 1.3 reaches levels in excess of the value of dλ/dH for terphenol D due to the compensation of magnetic anisotropy.
Original Russian Text ? I.S. Tereshina, S.A. Nikitin, G.A. Politova, A.A. Opalenko, E.A. Tereshina, I.V. Telegina, 2009, published
in Fizika Tverdogo Tela, 2009, Vol. 51, No. 1, pp. 85–90. 相似文献
10.
E. D. Politova D. A. Strebkov A. V. Mosunov N. V. Golubko G. M. Kaleva N. V. Sadovskaya S. Yu. Stefanovich 《Bulletin of the Russian Academy of Sciences: Physics》2018,82(3):269-272
Features are studied of the phase formation, structural parameters, microstructure, and dielectric and ferroelectric properties of non-stoichiometric (Na0.5 + xBi0.5)TiO3 ceramics with x = 0–0.1. The investigated samples exhibit ferroelectric phase-transition behavior as anomalies and peaks in dielectric permittivity near 400 and 600 K, respectively. Study of the second harmonic generation shows that phase transitions near 400 K exhibit relaxor-type behavior, indicating there are polar regions in the nonpolar matrix. An increase in the Na/Bi ratio in the initial compositions improves the dielectric and ferroelectric properties of the ceramics. 相似文献