Physics

Chaos in the System of Three Coupled Rotators: from Anosov Dynamics to Hyperbolic Attractor

The work presents an example of a system with chaotic dynamics built of three rotators by modifying a conservative system with hyperbolic Anosov dynamics. Results of a computational study of chaotic dynamics are considered (portraits of attractors, time dependences of the variables, Lyapunov exponents, and spectra) and good correspondence is observed between the dynamics on the attractor of the proposed system with the reduced model, characterized by the Anosov dynamics at appropriately defined energy.

IR Spectra of Salol and theirs Interpretation by Molecular Modeling

Authors: Babkov L. M., Davydova N. A., Ivlieva I. V.

IR spectra of salol have been measured at stable and metastable phases at temperature range from 11 to 298 K. IR spectra are different. We suggest that conformational mobility of salol and influence of H-bonding are responsible for the differences.

Calculation of Scale Factors for Quantum-mechanical Force Fields

Authors: Berezin K. V., Novoselova A. V., Chernavina M. L., Berezin V. I., Novoselov V. V.

A computer-assisted method for the calculation of scaling factors for refining the quantum-mechanical force fields of polyatomic molecules by the Pulay technique is suggested. The method is an iteration procedure and does not involve the calculation of derivatives of the frequencies of vibrations with respect to the scaling factors.

Phase Dynamics Modeling Technique for Estimation of Delayed Couplings between Nonlinear Oscillators Accounting for Influence of Amplitudes

Authors: Sidak E. V., Smirnov D. A., Bezruchko B. P.

An established interval estimator of a time delay in coupling between oscillators, which is based on empirical modeling of phase dynamics and maximum likelihood formalism, is shown to give sometimes erroneous conclusions about the value of the time delay. It occurs when the dynamics of amplitudes affects phases, which is typical of nonlinear oscillatory systems under the influence of strong noises or in chaotic regimes. We suggest an empirical criterion to diagnose such situations and a modified estimator of time delay which allows one to avoid erroneous conclusions.

Morphological Changes in Transplanted Sarcoma S45 at Photodynamic Therapy Using Nanocomposites Based on Gold Nanorods

Authors: Bucharskaya A. B., Genina E. A., Bashkatov A. N., Terentyuk G. S., Navolokin N. A., Maslyakova G. N., Khlebtsov N. G., Khlebtsov B. N., Tuchin V. V.

Photodynamic therapy (PDT) of cancer is an advanced application of gold nanostructures. The purpose of the research is to study the morphological changes in the transplanted sarcoma S45 at PDT using nanocomposites based on gold nanorods (GNRs). GNRs synthesized with the germ method and covered by a silicon coating, functionalized by hematoporphyrin, were intratumorally injected in rats with transplanted sarcoma S45. The tumor was irradiated by He-Ne laser with a wavelength of 632.8 nm.

Morphology of Gas Sensitive Tin Dioxide Thin Films Operating at Room Temperature

Authors: Venig S. B., Mahdi O. S., Malyar I. V., Sinyov I. V., Smirnov A. V., Kisin V. V.

Tin dioxide thin films sensing ethanol vapors above the room temperature (38° C) were deposited by RF magnetron sputtering onto silicon substrates. Microstructure measurements using scanning electron microscopy and atomic force microscopy demonstrate that samples consist of grains shaped rods with nanometer diameters which are oriented normally to the substrate surface. There are pores between the grains penetrating the entire thickness of the films.

Production of Tungsten Spherical Microparticles in Ultrasonic Field at Presence an Activator

Authors: Smirnov A. V., Atkin V. S., Grebennikov A. I., Revzina E. M., Kondrateva O. Y., Sinyov I. V.

It has been shown by experiments, that spherical tungsten microparticlein etching solution under the ultrasonic exposure is possible. The process of obtaining consists of two stages. At the first stage, by centrifuging a suspension of tungsten powder with an average particle size of 0.5 microns in the activator – etching from a water solution of potassium hydroxide and potassium ferricyanide, obtained tungsten thin plate of any shape, thickness 1–3 micrometers.

Plasmonic Rectification of Terahertz Radiation in a Grating-gated Graphene

Authors: Mashinsky K. V., Fateev D. V., Popov V. V.

The theory of the plasmonic rectification of terahertz radiation in a homogeneous graphene gated by a metal grating with an asymmetric unit cell is developed.

Compensation for Losses in a Resonant Circuit when Using Inertial Inductive and Capacitive Two-poles

Authors: Anishchenko V. S., Hohlov A. V.

Generalized linear inertial two-poles are introduced, and the eigen-oscillations are consi-dered in a series resonant LCR-circuit with a second-order inertial inductive element. It is shown that the introduction of the second order element is equivalent to entering negative damping into the resonant circuit.

On the Use of Optical Clearing in Strengthening the Sclera by Collagen Photocrosslinking

Authors: Shvachkina M. E., Pravdin A. B.

In the paper, the first evaluation results on the effect of optical clearing on the efficiency of the technique of eye sclera strengthening through the formation of riboflavin / ultraviolet collagen photocrosslinks are presented.

Physics

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