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231.
It is shown that several longitudinal domains of high absorption are formed under certain conditions in an optically bistable element based on increasing absorption under the action of a hyper-Gaussian light beam. This is caused both by the transformation of the initial beam profile into a tubular distribution and by the diffraction of light by a nonuniform boundary of the region of high absorption. The analysis of dynamics showed the possibility of formation of quasi-stationary regions with high absorption, which exist during a certain time. These effects can lead to false data recording in three-dimensional optical recording systems. 相似文献
232.
L. V. Baikalova L. N. Sobenina A. I. Mikhaleva I. A. Zyryanova N. N. Chipanina A. V. Afonin B. A. Trofimov 《Russian Journal of Organic Chemistry》2001,37(12):1736-1740
Condensation of 5-amino-3-(2-pyrrolyl)pyrazoles with 1-vinyl(ethyl)-2-formylimidazoles afforded complex heterocyclic ensembles: Schiff bases containing pyrrole, pyrazole, and imidazole rings. The cis,trans-orientation of CH = N and CH2 = CH groups and E-isomeric structure of the Schiff bases under study with respect to the imine fragment, and also the presence of intra- and intermolecular hydrogen bonds were established. 相似文献
233.
L. V. Klyba V. N. Bochkarev L. Brandsma O. A. Tarasova N. A. Nedolya B. A. Trofimov 《Russian Chemical Bulletin》2000,49(9):1548-1551
The influence of the position and nature of the substituent in the thiophene ring on the fragmentation of 3-alkyl- and 5-alkyl-2-thienylamines
under electron impact was studied. The derivatives containing the ethyl group in position 3 decompose due to both the elimination
of the fragments from the substituents and thiophene ring rupture. In the case of the compounds with thetert-butyl group in position 5, the last process is not observed. The fragmentation of the 3- and 5-methyl-substituted derivatives
occurs mainly from the isomeric thiopyran form of the molecular ion.
For Part 2, see Ref. 1.
Deceased.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1560–1563, September, 2000. 相似文献
234.
Z.-C. Fu J. Dai T. Li H.-Y. Liu Q.-F. Dai L.-J. Wu S. Lan S.-L. Tie X. Wan A. V. Gopal V. A. Trofimov T. M. Lysak 《Applied physics. B, Lasers and optics》2012,108(1):61-66
Femtosecond laser ablation based on two-photon absorption was employed to cut ZnO nanorods into uniform ZnO nanoparticles of deep subwavelength size. The fabricated ZnO nanoparticles possess a shorter mean transport length for photons at the emission wavelength and a much smaller scattering cross section at the pump wavelength, leading to highly efficient two-photon-pumped random lasing with a low threshold of ??8?mJ/cm2. It was demonstrated that the significant enhancement in two-photon luminescence after the irradiation of femtosecond laser pulses could also be utilized for realizing optical data storage. 相似文献
235.
The feasibility of an optical switch of femtosecond range controlled by a femtosecond light pulse acting on a nonlinear one-dimensional photonic crystal (a layered one-dimensional periodic structure) is demonstrated by computer simulation. The crystal comprises linear and weakly defocusing layers. It is shown that switching occurs when the peak intensity of the initial pulse exceeds a certain threshold value due to the dependence of the transmission-reflection bands of the photonic crystal on the nonlinearity of the medium. 相似文献
236.
A. Yu. Mester A. N. Trofimov M. V. Zamoryanskaya A. M. D’yakonov 《Technical Physics》2014,59(10):1536-1539
The rate of formation of a hydrocarbon film on the surface of a sample subjected to the action of an electron beam is studied at room temperature and in cooling a sample to the liquid nitrogen temperature. The thickness and the optical radiation transmission of such films are measured as functions of the electron beam radiation time, the sample temperature, and the level of vacuum. The film thickness is measured with atomic force microscopy. The absorption of the films is determined by comparing the cathodoluminescence intensities from a pure sample surface and from the surface covered with a film. The experimental results can be used to estimate the film formation rate as a function of the sample temperature and the vacuum and to determine the optical radiation absorption at a wavelength of 300, 360, 550, and 665 nm. 相似文献
237.
238.
Boris A. Trofimov Lidiya N. Parshina Anatolii P. Tantsyrev Oksana V. Vysotskaya Nina K. Gusarova 《Tetrahedron》2007,63(47):11661-11665
Vinyl ethers, promising chiral carbohydrate synthons, have been synthesized by the addition of glucose acetals (1,2:5,6-di-O-isopropylidene-α-d-glucofuranose, methyl 4,6-O-benzylidene-α-d-glucopyranoside, 1,2-O-cyclohexylidene-α-d-glucofuranose, methyl α-d-glucopyranoside) to acetylene under atmospheric and elevated pressures in an autoclave in the presence of superbase catalytic systems (KOH-DMSO, t-BuOK-DMSO). The complete vinylation of 1,2:5,6-di-O-isopropylidene-α-d-glucofuranose and methyl α-d-glucopyranoside has been realized under elevated pressure of acetylene in the system KOH-THF as well. 相似文献
239.
240.
B.V. Timokhin A. I. Golubin O. V. Vysotskaya V. A. Kron L. A. Oparina N. K. Gusarova B. A. Trofimov 《Chemistry of Heterocyclic Compounds》2002,38(8):981-985
Non-catalytic addition of 1,2,4-triazole to vinyl ethers and esters occurs on heating (65-175°C, 4-20 h) to give Markovnikov adducts (yield 30-100%). Electron-deficient alkenes (acrylonitrile, acrylic acid, 4-phenyl-3-buten-2-one) react with 1,2,4-triazole (78-190°C, 4-20 h) to give anti-Markovnikov adducts in yields of 45-83%. 相似文献