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排序方式: 共有138条查询结果,搜索用时 15 毫秒
1.
M. R. Allazov Ali Riza Kul A. V. Einullaev M. B. Babanly 《Russian Journal of Inorganic Chemistry》2006,51(4):624-629
Some polythermal sections of the Ni-Bi-Se system have been investigated by DTA, X-ray powder diffraction, microstructural analysis, and microhardness measurements. The liquidus surface has been constructed for this system. The compounds NiBi2Se4 and Ni3Bi2Se2 are formed by dystectic reactions and melt at 1088 and 980 K, respectively. The regions of primary and joint phase crystallization have been determined. A commutation of Bi2Se3-based thermoelements with a metal nickel bus-bar has been proposed. 相似文献
2.
The pseudopotential augmented-plane-wave method was used to study the surface structure of thin copper films with monolayers of Co, Ni, and Cs. Local densities of electron states, distributions of charge densities in the layers, and electron energy spectra are analyzed. The effect of adsorbates on the electronic properties of the Cu(001) surface and work function are discussed. Satisfactory agreement with available experimental data has been obtained. 相似文献
3.
Yu. N. Kul’chin O. B. Vitrik A. Yu. Zhizhchenko A. G. Mirochnik E. V. Fedorenko 《Optics and Spectroscopy》2012,112(4):514-518
The optical properties of a new photorecording polymer based on 2,2-difluoro-4-(9-anthracyl)-6-methyl-1,3,2-dioxaborine have
been investigated. This material is found to change its absorption coefficient and refractive index in the visible range under
illumination with a wavelength λ = 405.9 nm. This circumstance makes it possible to record static holograms with a spatial
frequency up to 2500 lines/mm, a diffraction efficiency above 60%, and a lifetime more than 6 months. A dynamic change in
the effective refractive index of this material under 405.9-nm irradiation is found, due to which one can form control optical
elements of the light-light type with a modulation frequency up to 50 Hz in it. 相似文献
4.
Electrochemical Properties of Hollow‐Structured MnS–Carbon Nanocomposite Powders Prepared by a One‐Pot Spray Pyrolysis Process 下载免费PDF全文
Spherical, hollow MnS? C composite powders were prepared from a solution of manganese salt, thiourea, and sucrose by one‐pot spray pyrolysis. The MnS? C composite powders were generated by direct sulfidation of MnO with hydrogen sulfide gas generated in situ by decomposition of thiourea during spray pyrolysis. Sucrose, which is used as a carbon source material, plays a key role in the formation of the MnS? C composite powders by improving the reducing atmosphere around the powders. Dot‐mapping images of the composite powders demonstrated uniform distribution of the manganese, sulfur, and carbon components within the MnS? C composite powder. Fine crystals of MnS were uniformly mixed with carbon derived from polymerization and carbonization of sucrose. The carbon content of the MnS? C composite powders was 26 wt %. The discharge capacities of the MnS? C composite powders in the 2nd and 200th cycles were 863 and 967 mA h g?1, respectively, at a current density of 1000 mA g?1. The spherical and hollow morphology of the MnS? C composite powders was completely retained, even after 200 cycles. The enhanced cycling and rate performance of the MnS? C composite powders is ascribed to the structural stability of the composite powders. 相似文献
5.
V. M. Kornilov A. N. Lachinov D. D. Karamov I. R. Nabiullin Yu. V. Kul’velis 《Physics of the Solid State》2016,58(5):1065-1070
This paper presents the results of an experimental investigation of the supramolecular structure of polydiphenylenephthalide thin films that exhibit effects of resistive switching. The supramolecular structure of the polymer has been investigated using small-angle neutron scattering in conjunction with atomic force microscopy. It has been found that the internal structure of polymer films consists of structural elements in the form of spheroids. The sizes of the structural elements, which were obtained from the neutron scattering data and analysis of the atomic force microscopy images, correlate well with each other. A model of the formation of polymer layers has been proposed. The observed structural elements in polymer films are formed due to the association of macromolecules in the initial polymer solution. 相似文献
6.
P. V. Gurin V. A. Kul’bachinskiĭ Yu. A. Danilov B. N. Zvonkov B. A. Aronzon A. B. Davydov V. V. Ryl’kov 《Journal of Experimental and Theoretical Physics》2007,105(1):181-184
Samples containing InGaAs quantum wells with p-type conductivity delta-doped by Mn were synthesized and studied. Magnetic moment measurements on a SQUID magnetometer revealed the presence of ferromagnetism at temperatures T from 4.2 to 400 K. Anomalous Hall effect caused by additional sample magnetization was observed at temperatures of from about 30 to 80 K. The Shubnikov-de Haas effect was recorded at 4.2 K. Negative magnetoresistance changed sign for positive at T ≈ 30 K as the temperature increased. 相似文献
7.
Soo Chool Lee Min Sun Cho Suk Yong Jung Chong Kul Ryu Jae Chang Kim 《Adsorption》2014,20(2-3):331-339
A range of potassium-based alumina sorbents were fabricated by impregnation of alumina with K2CO3 to examine the effects of the structural and textural properties of alumina on the CO2 sorption and regeneration properties. Alumina materials, which were used as supports, were prepared by calcining alumina at various temperatures (300, 600, 950, and 1,200 °C). The CO2 sorption and regeneration properties of these sorbents were examined during multiple tests in a fixed-bed reactor in the presence of 1 vol% CO2 and 9 vol% H2O. The regeneration capacities of the potassium-based alumina sorbents increased with increasing calcination temperature of alumina. The formation of KHCO3 increased with increasing calcination temperature during CO2 sorption, whereas the formation of KAl(CO3)(OH)2, which is an inactive material, decreased. These results is due to the fact that the structure of alumina by the calcination temperature is related directly to the formation of the by-product [KAl(CO3)(OH)2]. The structure of alumina plays an important role in enhancing the regeneration capacity of the potassium-based alumina sorbent. Based on these results, a new potassium-based sorbent using δ-Al2O3 as a support was developed for post-combustion CO2 capture. This sorbent maintained a high CO2 capture capacity of 88 mg CO2/g sorbent after two cycles. In particular, it showed a faster sorption rate than the other potassium-based alumina sorbents examined. 相似文献
8.
B. M. Bulychev R. A. Lunin V. A. Kul’bachinskii R. V. Shpanchenko V. I. Privalov 《Russian Chemical Bulletin》2004,53(8):1686-1692
One- or two-step reactions of potassium and rubidium fullerides with composition Mk C60 (M = K, Rb; k = 3—6) and K6C60 + m K mixtures (m = 1, 3) with anhydrous salts MCl3 (M = La, Pr, Nd, Sm, Gd, Tb, Yb, Lu, Y, Sc) and YbI2 in a toluene—THF medium afforded heterometallic fullerides M3–nMnC60 (n = 1—3). Among these compounds, substituted fullerides with composition M2MC60 (M = Yb, Lu, Sc) display superconducting properties with critical temperatures of 14—20 K.Published in Russian in Izvestiya Akademii Nauk.
Seriya Khimicheskaya, No. 8, pp. 1623–1628, August, 2004. 相似文献
9.
V. E. Egorushkin S. E. Kul’kova N. V. Mel’nikova A. N. Ponomarev 《Journal of Experimental and Theoretical Physics》2005,101(2):350-356
The dissociation of a gas molecule and the formation of a new chemical bond upon adsorption of this molecule on the surface of a transition metal are studied using the method of equations of motion. It is shown that both processes involve the formation of a mixed intermediate state during the adsorbate-substrate interaction. The dissociation is caused by a resonance growth of the vibrational mode, whereby the dissociation barrier is determined by the hybridization energy and by the frequency of electron transitions between molecular levels and the d electron energy levels of the metal in the mixed intermediate state. The resonance conditions for the formation of new surface structures are established. 相似文献
10.
V. V. Novikov A. V. Matovnikov T. A. Chukina A. A. Sidorov E. A. Kul’chenkov 《Physics of the Solid State》2007,49(11):2034-2037
This paper reports an experimental study of the heat capacity and crystal lattice parameters of a polycrystalline sample of yttrium diboride prepared by high-temperature synthesis from elements. The electronic and lattice contributions to the heat capacity are isolated. The temperature dependences of the characteristic temperature, the linear thermal expansion coefficients αa(T) and α c (T), the bulk thermal expansion coefficient β(T), and the Grüneisen coefficient are calculated. A region of negative values of α c (T) and β(T) is revealed. Anharmonicity is found to exert only a minor effect on the YB2 lattice dynamics over a larger part of the temperature range covered. 相似文献