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21.
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
22.
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
23.
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
24.
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
25.
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
26.
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
27.
28.
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
29.
V. S. Mal’kov D. A. Kokova A. S. Knyazev T. I. Izaak D. V. Nepomnyashchikh L. N. Kurina 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(4):690-694
A procedure for the purification of aqueous glyoxal (obtained by the partial oxidation of glycol) from carboxylic acids was
described. Mono- and dibasic organic acids can be removed from solution without any substantial losses of glyoxal by using
weakly basic EDE-10P and AN-31 anionites. A mechanism of the adsorption of carboxylic acids on weak resins was suggested based
on the IR spectra recorded in a study of AN-31 anion-exchange resin. Using this method of purification also allowed the removal
of the glyoxal condensation products from solution. 相似文献
30.
The molecular structure and vibrational spectra of trimethylarsenite were studied by gas phase electron diffractometry and IR and Raman spectroscopv. The configuration of the O-methyl groups with respect to the lone electron pair of the arsenic atom is established to be close to gosh-gosh-trans. The main geometrical parameters are: bond lengths (ra, Å) As-O 1.780, C-0 1.451, and C-H 1.101; bond angles (deg) As-O-C 115.0, O-As-0 99.5, and O-C-H 115.3. The experimental IR and Raman spectra were obtained for pure liquid and CCl4 solution. The frequencies and forms of normal vibrations were calculated. 相似文献