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1.
Kompan M. E. Agafonov D. V. Bursian A. E. Dmitriev D. S. Mikryukova M. A. 《Physics of the Solid State》2016,58(12):2555-2559
Physics of the Solid State - The heats of wetting have been measured experimentally for some of the solvents used for the preparation of electrolytes of supercapacitors. For the first time, the... 相似文献
2.
A phenomenological model of second-harmonic generation (SHG) in ferroelectrics in the absence of phase matching is considered. It is shown that conversion efficiency can be increased owing to a strong dependence of the second-order susceptibility on the second-harmonic intensity. The dependence of the conversion efficiency on the pump wave intensity is studied. 相似文献
3.
A. G. Razdobarin S. A. Basun V. é. Bursian L. S. Sochava D. R. Evans 《Physics of the Solid State》2010,52(4):706-711
A new iron center in stoichiometric lithium niobate crystals has been studied by the EPR method. The angular dependences of
the EPR spectrum of the center have been used to derive the parameters of its spin Hamiltonian. The data amassed on the variation
in the concentrations of two iron centers in lithium niobate crystals annealed in a Li2CO3 powder have provided an insight into the mechanism of formation of the new center, as well as corroborated its model proposed
by us earlier. According to this model, the center represents a complex of two defects aligned with the polar axis in the
crystal: the iron ion at the niobium site and an interstitial lithium ion filling the nearest structural vacancy (Fe3+[Nb]-Li+[V]). The structure of other Fe3+ centers revealed earlier in LiNbO3 crystals, in which the iron ion occupies the niobium site, has been discussed. 相似文献
4.
Results of investigations of changes in the state of a ferroelectric crystal, through which an intense electromagnetic-energy flux is transmitted, are analyzed. It is found that the main parameters determining the phase transition change significantly in this case. In addition, some phenomena develop which are characteristic only of open thermodynamic systems (self-assembling dissipative structures arise). These phenomena manifest themselves upon generation of the second optical harmonic in crystals where natural matching is absent. 相似文献
5.
M. P. Kurlykin A. E. Bursian O. V. Golub A. P. Filippov A. V. Tenkovtsev 《Polymer Science Series B》2016,58(4):421-427
Multicenter alkylene-aromatic polyester initiators for the cationic polymerization of oxazolines are synthesized via the high-temperature polycondensation of 2-[4-(2-Br-ethyl)]phenylsulfonyl hydroquinone with 4,4'- (alkanoyldioxydibenzoyl)dichlorides. The Kuhn segment values, liquid-crystalline properties, and molecularmass characteristics of the macroinitiators are determined. It is shown that the obtained polyesters may be used as initiators for the cationic polymerization of 2-ethyl-2-oxazoline. The graft copolymers form aqueous micellar solutions with a narrow particle-size distribution and possess a lower critical solution temperature. 相似文献
6.
Second harmonic generation (SHG) of light in iron-doped BaTiO3 crystals occurs primarily at an angle of about 7° to incident λ=1.06 μm radiation. It is shown that the quasisynchronism is accounted for by a 90° domain structure with a spatial wave vector q∥[011] and a spatial period of about 3 μm. This result may serve as a basis for interpretation of the anomalous SHG enhancement near the phase transition.
Fiz. Tverd. Tela (St. Petersburg) 41, 1076–1079 (June 1999) 相似文献
7.
Ya.G. Girshberg R.Kh. Kalimullin V.A. Egorov E.V. Bursian 《Solid State Communications》1985,53(8):633-636
The new mechanism of charge and heat transfer in ferroelectric is theoretically and experimentally investigated. It is shown that below the phase transition the presence of abnormal electron and phonon mean values leads to the appearance of polar components of the thermocurrent and heat flow. These components are proportional to the spontaneous polarization vector and are independent of the temperature gradient direction. 相似文献
8.
A. É. Bursian N. V. Klimova L. I. Rudaya I. M. Sokolova V. A. Lukoshkin G. K. Lebedeva 《Physics of the Solid State》2008,50(3):557-561
The time dependence of the nonlinear optical properties of the films prepared from silicon-containing poly(o-hydroxyamide) with a covalently bound 4-nitroazobenzene-based chromophore in a side chain is investigated in isothermal and thermally stimulated modes. It is revealed that, when the onium salt, i.e., triphenylsulfonium hexafluorophosphate, is added to a polymer solution, the second harmonic generation signal is characterized by an unusual time dependence. The assumption is made that the introduction of the onium salt favors the formation of the benzoxazole structure during the process of polarization (poling). This structure facilitates the orientation of nonlinear optical fragments and, hence, leads to an improvement of the nonlinear optical properties of the polymer film. 相似文献
9.
M. Ya. Goikhman L. I. Subbotina I. V. Gofman A. V. Yakimanskii A. E. Bursian V. A. Lukoshkin G. N. Fedorova A. V. Sidorovich O. E. Praslova N. N. Smirnov I. V. Abalov V. V. Kudryavtsev 《Russian Chemical Bulletin》2005,54(6):1481-1487
A new method was elaborated for the introduction of chromophores into the side chains of polymers by esterification of polyamidoimides
containing side carboxy groups with glycidyl ethers of dyes, 4-(4-nitrophenylazo)phenol and 4-(6-nitrobenzothiazol-2-ylazo)phenol.
The optimum modification conditions were found that made it possible to esterify 15, 30, 50, and 90% of the carboxy groups.
The synthesized polymers possess valuable physicomechanical properties (E = 2.8–3.3 GPa, σu = 69–90 MPa, εu = 38–77%) and glass transition temperatures of 115–125 °C, depending on the degree of esterification. After chromophore orientation
in the corona discharge, all the polymers demonstrate nonlinear optical properties of the second order.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1438–1444, June, 2005. 相似文献
10.
S. A. Basun V. É. Bursian A. G. Razdobarin L. S. Sochava 《Physics of the Solid State》2001,43(6):1059-1071
An EPR study has revealed light-induced recharging and optical alignment of the Fe Ta 4+ -V O tetragonal complexes in KTaO3. The data on the optical creation and destruction of this center by light of different polarizations and wavelengths are discussed together with similar results obtained for the Fe K 3+ -Oi center. These two centers were established to undergo mutual charge transfer, in which the electron released in the photoionization of the Fe K 2+ -Oi center is trapped by the Fe Ta 5+ -V O center. Irradiation by light with a photon energy below 2.05 eV, which is the ionization threshold of Fe K 2+ -Oi, reverses this process. In both cases, the absorption cross section depends on the orientation of the center axis relative to the light polarization vector. As a result, the Fe Ta 4+ -V O and Fe K 3+ -Oi tetragonal centers in KTaO3 acted upon by polarized light undergo orientation-sensitive light-induced recharging and the defects with the given charge state are no longer characterized by an equally probable distribution of the orientations of their axes over the three 〈100〉 directions. This mechanism, which does not involve real reorientations of the FeTa-V O and FeK-Oi complexes, gives rise, nevertheless, to the alignment of the centers along (or at right angles to) the light polarization vector. 相似文献