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1.
V. V. Kaminskii Toshihiro Kuzuya Shinji Hirai S. M. Solov’ev N. V. Sharenkova M. M. Kazanin 《Physics of the Solid State》2012,54(7):1345-1347
The electrical conductivity of SmS polycrystals has been studied in the temperature range 300?C870 K. It has been shown that, at 300 K ?? T ?? 700 K, the concentration of conduction electrons is determined by electron transfer from impurity donor levels, and at T > 700 K, by that from the samarium 4f levels. 相似文献
2.
The structure of a metallic-phase film produced by mechanical polishing of polycrystalline SmS 总被引:1,自引:0,他引:1
N. V. Sharenkova V. V. Kaminskii A. V. Golubkov L. N. Vasil’ev G. A. Kamenskaya 《Physics of the Solid State》2005,47(4):622-626
X-ray diffraction is used to study the structure of a metallic-phase film that forms during controlled polishing of homogeneous polycrystalline semiconducting Sm1+xS samples. Structural changes that appear in the semiconducting phase under these conditions were studied. The x dependence of the thickness of the metallic layer forming on the sample surface is analyzed to explain the effect of excess samarium ions on the transformation parameters. The cause of the stabilization of the metallic modification of SmS after polishing is terminated is explained using estimates based on the measured sizes of coherent domains in samples of different compositions. The appearance and stabilization of the metallic phase are related to a decrease in and subsequent conservation of the coherent-domain size, respectively. 相似文献
3.
L. N. Vasil’ev V. V. Kaminskiĭ M. V. Romanova N. V. Sharenkova A. V. Golubkov 《Physics of the Solid State》2006,48(10):1884-1886
The experimental dependence of the concentration of conduction electrons on the size of x-ray coherent scattering regions is obtained. The dependence is analyzed within the previously developed concentration model of the energy spectrum of samarium sulfide SmS. It is shown that the impurity donor levels in the SmS compound correspond to the samarium defect ions located at the boundaries of coherent scattering regions. 相似文献
4.
B. N. Bogomolov N. F. Kartenko D. A. Kurdyukov L. S. Parfen’eva A. A. Sysoeva N. V. Sharenkova I. A. Smirnov H. Miserek J. Mucha A. Jezowski 《Physics of the Solid State》1999,41(2):313-318
Samples of the nanocomposite opal + NaCl with 100% filling of first-order voids in the opal by NaCl have been obtained. The
thermal conductivity of the nanocomposite has been measured in the temperature interval 4.2–300 K. It is shown that NaCl,
introduced into opal, forms a regular “matrix quasilattice” of microcrystals, which leads to suppression of coherent effects
and, as a consequence, of properties characteristic of massive crystals.
Fiz. Tverd. Tela (St. Petersburg) 41, 348–353 (February 1999) 相似文献
5.
V. V. Kaminski? A. V. Golubkov V. A. Didik M. V. Romanova E. A. Skoryatina V. P. Usacheva B. N. Shalaev N. V. Sharenkova 《Physics of the Solid State》2009,51(10):2014-2018
The processes of diffusion of samarium and europium in nonstoichiometric samarium sulfide (SmS) at temperatures in the range 950–1600°C have been investigated by the radioactive isotope method and the method of weight loss upon evaporation of excess samarium. It has been found that there is a correlation between the diffusion coefficient D and the size of coherent X-ray scattering regions in SmS samples, as well as between the diffusion coefficient and the degree of deviation from the stoichiometric composition: the diffusion coefficient of impurities decreases as the size of coherent X-ray scattering regions increases and the stoichiometric composition is approached. The calculation of the diffusion coefficient of electrons in samarium sulfide at T = 77–300 K has demonstrated that the value of D increases with increasing temperature and increasing size of coherent scattering regions. 相似文献
6.
L. S. Parfen’eva T. S. Orlova N. F. Kartenko N. V. Sharenkova B. I. Smirnov I. A. Smirnov H. Misiorek A. Jezowski J. Mucha A. R. de Arellano-Lopez J. Martinez-Fernandez 《Physics of the Solid State》2009,51(10):2023-2031
This paper reports on measurements (in the temperature range T = 5–300 K) of the thermal conductivity κ(T) and electrical conductivity σ(T) of the high-porosity (~63 vol %) amorphous biocarbon preform with cellular pores, prepared by pyrolysis of sapele wood at the carbonization temperature 1000°C. The preform at 300 K was characterized using X-ray diffraction analysis. Nanocrystallites 11–30 Å in ize were shown to participate in the formation of the carbon network of sapele wood preforms. The dependences κ(T) and σ(T) were measured for the samples cut across and along empty cellular pore channels, which are aligned with the tree growth direction. Thermal conductivity measurements performed on the biocarbon sapele wood preform revealed a temperature dependence of the phonon thermal conductivity that is not typical of amorphous (and X-ray amorphous) materials. The electrical conductivity σ was found to increase with the temperature increasing from 5 to 300 K. The results obtained were analyzed. 相似文献
7.
L. I. Arutyunyan V. N. Bogomolov N. F. Kartenko D. A. Kurdyukov L. S. Parfen’eva I. A. Smirnov N. V. Sharenkova A. Jezowski J. Mucha H. Misiorek 《Physics of the Solid State》1998,40(2):348-349
An opal-based nanocomposite has been prepared with NaCl incorporated in its pores. The nanocomposite was produced by impregnating
the opal with a NaCl solution at room temperature. Thermal conductivity of the nanocomposite has been measured in the temperature
range 4.2–300 K. The effective heat conductivity of the nanocomposite was found to be equal to that of pure opal. The observed
phenomenon can be explained by assuming that NaCl resides in opal pores in the form of noncontacting needles, thus precluding
heat propagation through it.
Fiz. Tverd. Tela (St. Petersburg) 40, 379–380 (February 1998) 相似文献
8.
L. S. Parfen’eva T. S. Orlova N. F. Kartenko N. V. Sharenkova B. I. Smirnov I. A. Smirnov H. Misiorek A. Jezowski J. Mucha A. R. de Arellano-Lopez J. Martinez-Fernandez F. M. Varela-Feria 《Physics of the Solid State》2006,48(3):441-446
The thermal conductivity κ and electrical resistivity ρ of a white-eucalyptus cellular carbon preform used to fabricate silicon-carbide-based (SiC/Si) biomorphic ceramics have been measured in the 5-to 300-K temperature interval. The carbon preform was obtained by pyrolysis (carbonization) of white-eucalyptus wood at 1000°C in an argon ambient. The κ(T) and ρ(T) relations were measured on samples cut along the tree growth direction. The experimental data obtained were processed. 相似文献
9.
V. N. Bogomolov N. F. Kartenko D. A. Kurdyukov L. S. Parfen’eva I. A. Smirnov N. V. Sharenkova H. Misiorek J. Mucha A. Jezowski 《Physics of the Solid State》2004,46(10):1961-1968
Samples of opal + NaCl nanocomposites with 100 and 80% filling of first-order opal voids by sodium chloride have been prepared. Their effective thermal conductivities, κeff, were measured in the temperature interval 5–300 K. The lattice thermal conductivity of NaCl loaded in the opal voids, κ ph op , was calculated from the measured κeff(T). The value of ph was found to be considerably smaller than the lattice thermal conductivity of bulk NaCl throughout the temperature interval studied. For T>20 K, this behavior of κ ph op (T) is accounted for by the presence of specific defects that form in NaCl loaded in opal voids. For T<20 K, κ ph op (T) is governed by boundary phonon scattering from bottlenecks in horn-shaped channels interconnecting the octahedral and tetrahedral first-order opal voids filled by sodium chloride. It was found that the value of κ ph op (T) in this temperature region depends substantially on the dimensions of the bottlenecks, whose thicknesses are related to the amount of the cristobalite forming in a near-surface layer of the amorphous SiO2 opal spheres in the course of preparation of the opal + NaCl nanocomposite. 相似文献
10.
L. S. Parfen’eva T. S. Orlova N. F. Kartenko N. V. Sharenkova B. I. Smirnov I. A. Smirnov H. Misiorek A. Jezowski F. M. Varela-Feria J. Martinez-Fernandez A. R. de Arellano-Lopez 《Physics of the Solid State》2005,47(7):1216-1220
The thermal conductivity κ and electrical resistivity ρ of a SiC/Si biomorphic composite were measured at temperatures T = 5–300 K. The composite is a cellular ecoceramic fabricated by infiltrating molten Si into the channels of a cellular carbon matrix prepared via pyrolysis of wood (white eucalyptus) in an argon ambient. The κ(T) and ρ(T) relations were measured on a sample cut along the direction of tree growth. The experimental results obtained are analyzed. 相似文献