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491.
492.
N. F. Kartenko T. S. Orlova L. S. Parfen’eva B. I. Smirnov I. A. Smirnov 《Physics of the Solid State》2014,56(11):2348-2352
Natural composites (biocarbons) obtained by carbonization of beech wood at different carbonization temperatures T carb in the range of 800–2400°C have been studied using X-ray diffraction. The composites consist of an amorphous matrix and nanocrystallites of graphite and graphene. The volume fractions of the amorphous and nanocrystalline phases as functions of T carb have been determined. Temperature dependences of the phonon thermal conductivity κ(T) of the biocarbons with different temperatures T carb (1000 and 2400°C) have been analyzed in the range of 5–300 K. It has been shown that the behavior of κ(T) of the biocarbon with T carb = 1000°C is controlled by the amorphous phase in the range of 5–50 K and by the nanocrystalline phase in the range of 100–300 K. The character of κ(T) of the biocarbon with T carb = 2400°C is determined by the heat transfer (scattering) in the nanocrystalline phase over the entire temperature range of 5–300 K. 相似文献
493.
T. D. Orlova A. V. Katrovtseva S. A. Bychkova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(5):808-811
The heat effects of complex formation between zinc(II) and nickel(II) ions and succinic acid were determined calorimetrically
at 298.15 K and several ionic strength values against the background of NaNO3. The standard thermodynamic characteristics of complex formation in aqueous solution were calculated. 相似文献
494.
V. V. Danilov A. V. Baranov G. K. El’yashevich A. O. Orlova G. G. Khokhlov A. I. Khrebtov 《Optics and Spectroscopy》2010,108(6):941-946
The fluorescence of CdSe/ZnS semiconductor quantum rods (QRs) in the CdSe/ZnS-hexane pentylcyanobiphenyl and CdSe/ZnS-methyl
methacrylate pentylcyanobiphenyl multicomponent systems has been investigated. It is shown that the presence of pentylcyanobiphenyl
affects differently the QR fluorescence in each composite. The QR fluorescence in hexane solutions is efficiently quenched
in the presence of pentylcyanobiphenyl, whereas in the composites based on methyl-methacrylate the QR fluorescence is enhanced
as a result of the introduction of pentylcyanobiphenyl in the mesomorphic state. This difference is explained by the different
forms of pentylcyanobiphenyl in these systems. The composites based on structured porous polyethylene films containing QRs
in a mesomorphic medium have been obtained for the first time. The measured degree of polarization of the QR fluorescence
characterizes the composite as strongly ordered. 相似文献
495.
Aliev R. A. Aleshin G. S. Belyshev S. S. Ishkhanov B. S. Priselkova A. B. Pozharskaya V. Yu. Khankin V. V. Orlova M. A. Kalmykov S. N. 《Russian Chemical Bulletin》2017,66(2):373-375
Russian Chemical Bulletin - The yields of 66Ga, 67Ga, 68Ga, 70Ga, 65Zn, and 69mZn upon irradiation of gallium with the natural isotopic composition by the bremsstrahlung photon beam with the energy... 相似文献
496.
Kidalov S. V. Shakhov F. M. Lebedev V. T. Orlova D. N. Grushko Yu. S. 《Crystallography Reports》2011,56(7):1181-1185
The structure of detonation diamonds sintered at a high pressure (7 GPa) and temperatures of 1200–1700°C has been investigated
by small-angle neutron scattering. It is shown that sintering leads to an increase in the particle size from 6 to 30 nm and
established that this increase is due to the chainlike oriented attachment of particles. This study supplements the oriented-attachment
model, which was suggested based on the X-ray diffraction spectra of detonation nanodiamonds (DNDs) sintered under the same
conditions. 相似文献
497.
Synthesis and Characterization of Niobium-Bearing Members of the NZP and NbOPO 4 Structural Families
Vladimir Pet'kov Maxim Sukhanov Albina Orlova Maya Zharinova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1499-1501
Theoretically predicted by us, M 1/3 Nb 5/3 (PO 4 ) 3 (M = Mg, Mn, Co, Ni, Cu or Zn) compounds with the sodium zirconium phosphate (NZP) framework structure having no interstitial ions were synthesized. The rising of temperature above 900;C causes the change of chemical composition of NZP compounds and formation NbOPO 4 -like products. The phase formation regularities stated gave a possibility to choose optimal conditions for preparation of these phosphates. 相似文献
498.
T. S. Orlova J. Y. Laval Ph. Monod V. S. Zakhvalinski? V. M. Egorov Yu. P. Stepanov 《Physics of the Solid State》2009,51(1):99-105
The effect of copper doping on charge-orbital ordering in La1/3Ca2/3Mn1 − y
Cu
y
O3 (0 ≤ y ≤ 0.07) is studied by measuring the temperature dependences of the magnetization, the electrical resistivity, and the heat
capacity in combination with an electron microscopic investigation of the structure. It is demonstrated that copper doping
leads to a lowering of the charge ordering temperature T
CO and that this decrease is proportional to the decrease in the Mn3+ ion concentration. In the temperature range 5–300 K, the semiconducting pattern of the electrical resistivity persists for
all values of 0 ≤ y ≤ 0.07. Electron microscope studies have shown that the presence of copper suppresses the formation of a regular superstructure,
which is characteristic of the undoped starting compound, beginning already from low concentrations (y = 0.01). Differential scanning calorimetry revealed a substantial decrease in the transition entropy at the onset of charge
ordering in copper-doped samples as compared to the starting compound. Doping with copper destroys long-range charge-orbital
ordering and retains apparently only short-range order.
Original Russian Text ? T.S. Orlova, J.Y. Laval, Ph. Monod, V.S. Zakhvalinskiĭ, V.M. Egorov, Yu.P. Stepanov, 2009, published
in Fizika Tverdogo Tela, 2009, Vol. 51, No. 1, pp. 91–97. 相似文献
499.
K. S. Smuilovich N. A. Orlova E. V. Karpova M. M. Shakirov V. V. Shelkovnikov 《Russian Chemical Bulletin》2010,59(7):1408-1413
Polyfluorinated di-and triarylpyrazolines were synthesized by the reactions of polyfluorinated chalcones with hydrazine hydrate
and phenylhydrazine, respectively. Reactions of benzyl-idenepolyfluoroacetophenones with phenylhydrazine resulted in the mixtures
of isomeric 1,5-diphenyl-3-polyfluoroaryl-and 1,3-diphenyl-5-polyfluoroarylpyrazolines. Fluorescence properties of the synthesized
triarylpyrazolines were studied. 相似文献
500.
A. G. Beirakhov I. M. Orlova E. G. Il’in A. V. Churakov A. S. Kanishcheva Yu. N. Mikhailov 《Russian Journal of Inorganic Chemistry》2009,54(8):1217-1222
Uranylaqua complexes with N-methyl-, N-ethyl-, N-isopropyl-, and N,N-dimethylhydroxylamines were studied. The structure of [UO2{(CH3)2NO}2(H2O)2] was determined by X-ray crystallography. The N, N -dimethylhydroxylaminate ion is coordinated to uranyl through the nitrogen and oxygen atoms with the formation of a three-membered chelate ring. 相似文献