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21.
V. S. Kovivchak T. V. Panova K. A. Mikhailov E. V. Knyazev 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2013,7(3):531-535
The change in the morphology and surface composition of copper alloys (brass LS 59-1, bronzes BrOS 10-10 and BrAJ 9-4) upon irradiation with a high power ion beam of nanosecond duration is studied. It is shown that craters are mainly formed at the location of lead or sulfur inclusions. The reverse deposition of zinc onto the surface of brass is found. Possible mechanisms of these phenomena are considered. 相似文献
22.
A. V. Knyazev N. G. Chernorukov I. A. Letyanina Yu. A. Zakharova I. V. Ladenkov 《Journal of Thermal Analysis and Calorimetry》2013,112(2):991-996
In the present work, the temperature dependence of heat capacity of dipotassium diiron(III) hexatitanium oxide has been measured for the first time in the range from 10 to 300 K by means of precision adiabatic vacuum calorimetry. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity $ C_{p}^{ \circ } (T) $ , enthalpy $ H^{ \circ } (T) - H^{ \circ } (0) $ , entropy $ S^{ \circ } (T) - S^{ \circ } (0), $ and Gibbs function $ G^{ \circ } (T) - H^{ \circ } (0) $ for the range from T → 0 to 300 K. The structure of K2Fe2Ti6O16 is refined by the Rietveld method: space group I4/m, Z = 1, a = 10.1344(2) Å, c = 2.97567(4) Å, V = 305.618(7) Å3. The high-temperature X-ray diffraction was used for the determination of coefficients of thermal expansion. 相似文献
23.
N. G. Chernorukov O. V. Nipruk A. V. Knyazev M. I. Arova K. A. Chaplieva 《Russian Journal of Inorganic Chemistry》2013,58(1):9-13
Individual crystalline phases of composition MIIU3O10 · nH2O were prepared by reacting schoepite UO3 · 2.25H2O with aqueous solutions of Mg, Mn, Co, Ni, Cu, Zn, or Cd nitrates under hydrothermal conditions at 200°C. The composition and structure of the resultant compounds were determined by hightemperature X-ray diffraction, IR spectroscopy, scanning calorimetry, and chemical analysis; the dehydration and thermal destruction of the compounds were studied. 相似文献
24.
The effect of plasma on the amplitude of the wakefield excited in a dielectric structure by a relativistic electron bunch train is studied. The structure under study is a dielectric cylindrical waveguide with an axial drift channel filled with plasma. The dependences of the amplitude of a longitudinal electric field on the plasma density are obtained for the following three cases: the parameters of the dielectric structure and bunches are fixed; the inside or outside radius of the dielectric tube changes according a change in the plasma frequency, and the bunch repetition frequency is adjusted to the plasma frequency and the frequency of the first radial mode of a dielectric wave. It is shown that, when the eigenwave frequencies are adjusted to the bunch repetition frequency via a change in the structure radii, the maximum of the accelerating field is determined by a plasma wave, and there is a plasma density range where a dielectric wave significantly contributes to the total field amplitude. In the case of changing the outside radius, this range is substantially wider. 相似文献
25.
Yu. V. Knyazev Yu. I. Kuz’min V. S. Gaviko A. A. Inishev 《Physics of the Solid State》2016,58(9):1729-1734
The optical properties of intermetallic compounds TbNi2Mnx (x = 0, 0.5, 1) have been investigated using the ellipsometric method in the spectral range from 0.22 to 16 μm. The specific features of the modification of the dispersions of spectral characteristics with a variation in the manganese concentration have been determined. The behavior of the frequency dependences of the optical conductivity in the interband absorption region has been discussed in terms of the available data on the electronic structure of these compounds. The concentration dependences of a number of electronic parameters have been calculated. 相似文献
26.
用强子–弦级联模型JPCIAE及相应的Monte Carlo事例产生器研究相对论性核–核碰撞中带电粒子多重数的赝快度密度对能量和中心度的依赖关系.无需另调任何模型参数的条件下,此模型可以同时较好地描述相对论性pp实验数据及PHOBOS和PHENIX实验组的Au+Au实验数据.本文指出:因〈Npart〉并非严格定义的物理量,致使实验上和理论上确定〈Npart〉有一定任意性,从而使得每参加者核子对的带电粒子赝快度密度随着〈Npart〉的增加可能逐渐增大,也可能逐渐减小,因此用它来区分粒子产生机制是欠妥的. 相似文献
27.
S. I. Tyutyunnikov V. N. Shalyapin A. D. Belyaev A. N. Artemiev N. A. Artemiev B. F. Kirillov M. V. Kovalchiuk A. A. Demkiv G. A. Knyazev 《Physics of Particles and Nuclei Letters》2017,14(5):719-725
The performance of a multipurpose synchrotron spectrometer is diversified by installing additional equipment for the studies of diffraction in the Debye–Scherrer geometry. The design of X-ray optics and technical characteristics of the spectrometer are described. Diffraction patterns for polycrystals detected in both the forward and backward hemispheres are illustrated. 相似文献
28.
Burmasov V. S. Dolgov-Savel'ev G. G. Knyazev B. A. Fokin E. P. 《Journal of Applied Spectroscopy》1973,19(3):1230-1232
Journal of Applied Spectroscopy - 相似文献
29.
30.
S. A. Knyazev V. E. Korsukov M. M. Korsukova I. I. Pronin K. Schierbaum 《Technical Physics》2007,52(8):1098-1100
The effect of uniaxial tension on the behavior of graphite segregates (islets) on the surface of recrystallized platinum foil is studied in situ by low-energy electron diffraction and Auger electron spectroscopy. Mechanical stresses are shown to have a significant influence on the size and orientation of the islets. The alignment of the islets along steps on the platinum surface is discovered. 相似文献