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1.
Zarubitskii O. G. Budnik V. G. Omel'chuk A. A. Melekhin V. T. Opanasyuk V. P. Zakharchenko N. F. 《Russian Journal of Applied Chemistry》2002,75(4):558-561
Electrochemical separation of lead-silver alloys into the constituents by thin-layer electrolysis in molten electrolytes, with bismuth as metal separator, is studied. It is proposed to determine the extent of component recovery by potentiometry. 相似文献
2.
Times of longitudinal T
1b
and transverse T
2b
magnetic relaxation of hexane and decane molecules in micropores of ZSM-5 silicalite were measured as functions of the content of these liquid n-alkanes in zeolite and of temperature. The stepwise changes in the T
1b
and T
2b
times were revealed in the region of 8% content of hydrocarbons. The observed changes in the concentration and temperature dependences of T
1b
and T
2b
times are explained by the rearrangement of silicalite crystal lattice under the action of adsorbed molecules. 相似文献
3.
G. G. Pimenov V. D. Skirda V. Yu. Maksimenko V. P. Morozov O. A. Opanasyuk 《Colloid Journal》2004,66(6):722-725
Pulsed NMR and X-ray diffraction analysis are employed to study the influence of adsorbed toluene, p-xylene, acetone, and di(ethylene glycol) (DEG) molecules on phase transitions in a ZSM-5 silicalite. In the region of phase transitions, times T1 and T2 of longitudinal and transverse magnetic relaxation of apolar molecules adsorbed in silicalite micropores increase and decrease in a jumpwise manner, respectively, with a rise in the total content of the liquid. Such changes in T1 and T2 occur for hexane, decane, toluene, and p-xylene molecules. Qualitatively different concentration dependences of T1 and T2 are observed for polar acetone and DEG molecules, because these liquids do not cause a earrangement in the crystal lattice of silicalite; this is confirmed by the X-ray diffraction data.Translated from Kolloidnyi Zhurnal, Vol. 66, No. 6, 2004, pp. 802–806.Original Russian Text Copyright © 2004 by Pimenov, Skirda, Maksimenko, Morozov, Opanasyuk. 相似文献
4.
A new and general procedure is described for a detailed analysis of time-resolved fluorescence depolarisation data in the presence of electronic energy migration. An isotropic ensemble of bifluorophoric molecules (D(1)-R-D(2)) has been studied to demonstrate its utility. Intramolecular donor-donor energy migration occurs between the two donor groups (D), which are covalently connected to a rigid linker group (R). These groups undergo restricted reorientational motions with respect to the R group. The analysis of depolarisation data basically involves the search for best-fit parameters which describe the local reorientational motions, the intermolecular D(1)-D(2) distance, as well as the mutual orientations of the donors. For this, the analysis is partly performed on the Fourier domain and the best-fit parameters are determined by using an approach based on a Genetic Algorithm. The energy migration process has been described by using Monte Carlo simulations and an extended F?rster theory (EFT). It is found that the EFT provides the least time-consuming computational method. Since one-photon and two-photon excited fluorescence experiments can be applied for energy migration studies, a general and unified theoretical formulation is given. 相似文献
5.
6.
A. S. Opanasyuk D. I. Kurbatov V. V. Kosyak S. I. Kshniakina S. N. Danilchenko 《Crystallography Reports》2012,57(7):927-933
The phase composition, texture quality, size of coherent scattering domains, microstrain level, and concentration of stacking faults in zinc and cadmium chalcogenide (ZnS, ZnSe, ZnTe, CdSe, CdTe) films deposited by close-spaced vacuum sublimation method on nonorienting substrates have been investigated. The analysis was performed by X-ray diffraction. The substructural characteristics were determined from the physical broadening of diffraction lines using the Hall method and threefold convolution. The dependence of the structural properties of chalcogenide films on the deposition conditions are characterized. 相似文献
7.
Influence of substrate temperature on the structural and optical properties of crystalline ZnO films obtained by pulsed spray pyrolysis 下载免费PDF全文
Oleksandr Dobrozhan Denys Kurbatov Anatoliy Opanasyuk Hyeonsik Cheong Andreu Cabot 《Surface and interface analysis : SIA》2015,47(5):601-606
In this work, we report on the structural and optical properties of ZnO films deposited by pulsed spray pyrolysis at relatively low temperatures, compatible with a large variety of substrates and processing technologies. Crystalline ZnO films were deposited onto glass substrates using zinc acetate dihydrate dissolved in distilled water with concentration of 0.2 M. The temperature of the substrate was varied in the range Ts = 473–673 K with ΔТ = 50 K. Effect of Ts were investigated by scanning electron microscopy, x‐ray diffraction and energy dispersive x‐ray, and optical spectroscopies. Also, the influence of Ts on the grain size, phase composition, texture quality, coherent scattering domain size, crystal lattice parameters, chemical composition, transmission coefficient, and the bang gap of the ZnO films were studied. X‐ray diffraction analysis revealed that films were polycrystalline with hexagonal phase and showed as preferential orientation (101) at Ts < 573 K and (100) and (002) at Ts > 573 K. Scanning electron microscopy (SEM) measurements showed that the substrate temperature has a strong effect on morphology of the films. Energy dispersive analysis revealed that ZnO films consisted of the non‐stoichiometric compounds. Optical measurements showed ZnO films to be highly transparent in the visible region, and optical band gap is shifting from 3.18 eV to 3.30 eV. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
V. Kosyak A. Opanasyuk P.M. Bukivskij Yu.P. Gnatenko 《Journal of Crystal Growth》2010,312(10):1726-1730
The polycrystalline CdTe films were deposited by the close-spaced vacuum evaporation at the different substrate temperatures (150–550 °C). The X-ray diffraction measurements of structural and substructural properties of these films were carried out to study their phase composition and texture. The films’ parameters such as the coherent scattering domain size, microdeformation level and mean density of dislocations were determined based on the broadening of diffraction peaks. In this case the Hall and three-fold convolution approximations were used. Surface morphology, grain size and growth mechanism of the films were determined by the scanning electron microscopy. The low temperature photoluminescence measurements allowed us to establish the correlation between the point and extended defect structure on the one hand and the growth conditions on the other. As a result, the growth conditions of CdTe polycrystalline films with fairly good crystal and optical quality were determined. 相似文献
9.
Yu.P. Gnatenko P.M. Bukivskij А.S. Opanasyuk D.I. Kurbatov M.M. Kolesnyk V.V. Kosyak H. Khlyap 《Journal of luminescence》2012,132(11):2885-2888
Low-temperature photoluminescence (PL) spectra of CdTe and ZnTe films obtained by a close-spaced volume sublimation technique under different technological conditions (substrate temperatures) were investigated. Analysis of the experimental results made it possible to conclude that the nature of the structure of the PL spectra observed experimentally is caused by the recombination of the excitons bound to shallow neutral acceptors, donor–acceptor pairs with the participation of the complex acceptors, and the presence of the extended defects like dislocations. The presence of neutral acceptors is related to the Li, Na, P or Cu residual impurities. As a result of the study of the PL spectra of CdTe and ZnTe films the optimal temperature conditions of their growth were determined as the substrate temperature Ts=623 K and 673 K, respectively. 相似文献
10.
O. G. Zarubitskii V. P. Opanasyuk A. A. Omel''chuk N. F. Zakharchenko 《Russian Journal of Applied Chemistry》2001,74(2):209-213
The results obtained in a study of the electrochemical separation of multicomponent tin-based alloys in salt melts are presented. The influence exerted by electrolysis conditions on the discharge at the auxiliary electrode of a number of metals accompanying lead and tin was determined. 相似文献