Izvestiya of Saratov University.
ISSN 1817-3020 (Print)
ISSN 2542-193X (Online)


Физика

Resonant Self-Action and Non-Stationary Coherent Transients in Frequency-Modulated CW Laser Beams

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 Resonance Phenomena in Electrodynamic Systems with Metal, Dielectric and Semiconducting Inclusions

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 Investigation of the 4-Butil-4’-Cyanobiphenyl IR Spectra Transformations at the Temperature Changes

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.

Developing the System of Classification and Diagnostics for Ophtalmology Deseases with the Help of Artificial Neural Networks

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.

Vibrational Spectra фnd Structural Dinamic Models of Gb-, Gd-, Gf-Agents

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.

Multiple Light Scattering Investigation in Ppolymer Dispersed Liquid Crystals: Monte-Carlo Simulation

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.

Photodynamic Influence of Red (625 nm) and Infra-Red (805 nm) Radiation on Bacteria P. Acnes Processed by Photosensitizes

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

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.

Dielectric Resonators: The Integral and Integrodifferential Equations Methods

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 Н01δ and Н011 eigen oscillations of cylindrical dielectric resonator have been numerically investigated using the iteration technique.

Vibrational Spectra of Benzophenone Conformers

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

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