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31.
M. Brodyn V. Volkov V. Lyakhovetsky V. Rudenko V. Styopkin 《Applied physics. B, Lasers and optics》2013,111(4):567-572
Nonlinear optical response of Au island films to femtosecond laser pulses is studied in the vicinity but not exactly at the surface plasmon absorption peak (λ spr = 560 nm). The third-order nonlinear optical susceptibility is shown to be Reχ (3) = +1.7 × 10?7 esu and Reχ (3) = +1 × 10?7 esu at the wavelengths 800 and 460 nm, respectively. Kinetics of the optical nonlinear response has been studied for wavelengths 400 and 800 nm. It is believed that the origin of nonlinearity at the wavelengths is related to the free-electron heating in the conduction band and their further thermalization via electron–electron scattering, but at 400 nm the contribution to the nonlinear susceptibility because of interband d → s, p transitions is also possible. 相似文献
32.
G. A. Komandin A. A. Volkov O. E. Porodinkov I. E. Spektor S. V. Chuchupal 《Physics of the Solid State》2013,55(6):1236-1241
The dispersion analysis of the panorama reflection spectrum of ceramic calcium titanate has been performed following the additive and factorized dispersion models with the goal to reveal the degree of adequacy of each of these models for determining the dispersion parameters of phonon modes. The correspondence of longitudinal and transverse IR-active vibrations has been established for the cubic and orthorhombic phases. Giant LO-TO splitting of the low-frequency soft mode (700 cm?1), which leads to the inversion of the frequencies of all other IR vibrations in this region, has been found. This result is in good agreement with first-principles calculations. 相似文献
33.
34.
Georgiy O. Kachkovskyi Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2238-2242
Two synthetic routes to phosphonic analogues of indoprofen, a nonsteroidal anti-inflammatory drug, were developed by the cyclization of aniline 2 (method A) and by the Arbuzov reaction of corresponding alkylchloride 3 with triethylphosphite (method B). 相似文献
35.
K. G. Myakishev E. A. Il’inchik V. V. Volkov 《Russian Journal of Inorganic Chemistry》2012,57(9):1291-1294
Isopropylamine borane i-C3H7NH2 · BH3 was synthesized by the reaction of sodium tetrahydroborate NaBH4 with isopropylamine hydrochloride in tetrahydrofuran followed by extraction with diethyl ether. Its synthesis conditions were determined and optimized. The compound was characterized by chemical analysis, IR spectroscopy, and differential thermal analysis. 相似文献
36.
37.
Oleg G. Filippov 《Annals of Global Analysis and Geometry》1990,8(2):113-126
A decomposition of any pseudodifferential operator (D) onR
n
with almost periodic symbol as 113-1 1 is obtained in the paper, where
A
(D) is a pseudodifferential operator over a certainC
*-algebraA acting on sections of a vector bundle over a torusT
n whose fibre isA. The coincidence of spectra sp (D) = sp
A
(D) is proved for all (D) either bounded or elliptic. 相似文献
38.
Oleg Palumbíny 《Czechoslovak Mathematical Journal》2003,53(2):467-477
The paper deals with oscillation criteria of fourth order linear differential equations with quasi-derivatives. 相似文献
39.
Oleg Pikhurko 《Journal of Graph Theory》2003,42(3):220-233
We investigate the asymptotics of the size Ramsey number î(K1,nF), where K1,n is the n‐star and F is a fixed graph. The author 11 has recently proved that r?(K1,n,F)=(1+o(1))n2 for any F with chromatic number χ(F)=3. Here we show that r?(K1,n,F)≤ n2+o(n2), if χ (F) ≥ 4 and conjecture that this is sharp. We prove the case χ(F)=4 of the conjecture, that is, that r?(K1,n,F)=(4+o(1))n2 for any 4‐chromatic graph F. Also, some general lower bounds are obtained. © 2003 Wiley Periodicals, Inc. J Graph Theory 42: 220–233, 2003 相似文献
40.
V. A. Batanov V. S. Petriv A. O. Radkevich A. L. Telyatnikov A. Yu. Volkov 《International Journal of Infrared and Millimeter Waves》1991,12(7):703-715
High power IR pumping beams self focusing and defocusing in NH3 Raman laser is investigated by numerical methods on the basis of the solution of nonlinear quasioptical equations. The analysis of self focusing have been done for a wide range of parameters of radiation and of active medium. Spatial evolution of the beam configuration have been investigated for different regimes of nonlinear diffraction. Developed model enables to allow exactly for the spectroscopic features of active molecules and may be applied to the analysis of the properties of powerful optically pumped FIR lasers. 相似文献