Физика

Periodical modulation of frequency, typical for spectroscopic purposes, is numerically modelled in transversely limited, propagating through a saturable two-level absorber cw laser beams. At modulation periods comparable with the atomic relaxation times the time and frequency dependence of the output intensity exhibits the manifestations of delayed medium response, including time-dependent lens and aperture effects that may be of importance in spectroscopy.

The new types of resonances in electrodynamic reduced dimensionality systems with semiconductors, semiconducting structures are installed, the metal and dielectric inclusions and show a possibility of their use for want of to development and creation of new types of a semiconducting microwave of systems.

The IR spectra of the 4-butil-4’-cyanobiphenyl in the liquid and solid crystal states in the region 400−400 cm⁻¹ were measured at the 28–70°С temperature interval. The transformations of the spectra at the temperature changes are explained on the basis of the IR spectra calculation results performed with using of the LEV-100 software. A supposition about the conformational changes in the molecule made. The bands sensitive to the changes in its conformational structure were found and the interpretation of the IR spectra was given.

The system and methodology of classification and diagnostics of ophthalmology deseases (or different stages of particular desease, namely, glaucoma) on the basis of artificial neural networks (ANN) are presented. Classification is made using the selforganising Kohonen maps. Diagnostics is performed with the help of ANN of perceptron type.

An analysis of vibrational spectra of sarine, sorine, cyclosarine (GA-, GB-,GD-, GF-Agents) is carried out by the method DFT/B3LYP in the anharmonic approximation. It is possible to use the second order of anharmonic theory of vibrational spectra for the predictional calculation in phosphororganical compounds.

Theoretical investigation of angular dispersed of scattered light in polymer dispersed nematic liquid crystals with rather value of optical transmittance was presented in this article. Multiple light scattering was simulated by Monte-Carlo technique using differential cross section of liquid crystal droplet as a phase function. The obtained results have laid in the limits of experimental data and theoretical simulation based on anomalous diffraction approach.

It was shown, that Propionibacterium acnes was rather subjected to action of red and infrared radiation. The effect of the given radiation amplified at this bacteria by various solutions of photosensitizes. The received results are considered from the point of view of an estimation of light action efficiency in a combination to photosensitizes at photodynamic therapy skin suppurative inflammation diseases.

Mathematical model of drags and immersion liquids diffusion in human ocular tissues is presented. Analytic expressions are derived for diffusing liquid concentration, which give good approximations for exact solution at small or large time.

The volume integrodifferential and integral equations which are describing the stationary eigenmodes of open dielectric resonators have been considered and concretized for cylindrical case. The numerical algorithms for its solutions are proposed. The Н_01δ and Н₀₁₁ eigen oscillations of cylindrical dielectric resonator have been numerically investigated using the iteration technique.

In limits DFT B3LIP/ 6-31G* method have been analyse of geometrical structure and vibrational spectra of possible conformers of benzophenone.