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Formation of Modified Materials in Flows of Low-temperature Plasma

Authors: Serdobintsev A. A., Venig S. B., Alexandrov V. A., Mitin D. M., Veselov A. G., Kiryasov O. A., Elmanov V. I.

In this paper the results of experimental studies are presented. The experiments were aimed to synthesis of materials with modified properties. A special technique of synthesis in low-temperature plasma flows allows controlling film material parameters. The possibility to control optical, morphological and electrophysical properties is shown by the examples of ZnO and Si films.

Magnetic Composites with Embedded Magnetite Nanoparticles: Preparation, Control of Physical Properties, Applications

Authors: Voronin D. V., Sadovnikov A. V., Beginin E. N., Shchukin D. G., Gorin D. A.

The formation of nanocomposites with embedded magnetite nanoparticles using layer-by-layer deposition is described in this review. It was shown, that physical properties of these composites are controllable by the variation of the magnetic nanoparticles layers number in their structure. The review of some practical application of magnetic nanocomposite materials based on their controllable properties was carried out as well.

Investigation of Multilayers Structures Based on the Langmuir–Blodgett Films of CdSe/ZnS Quantum Dots

Authors: Gorbachev I. A., Chumakov A. S., Ermakov A. V., Kim V. P., Speranskaya E. S., Goryacheva I. Y., Glukhovsky E. G.

This article presents the results of a study QD Langmuir monolayers on the water subphase and LB films transferred onto a solid surface. The monolayers of CdSe/CdS/ZnS QD stabilized by oleic acid without of supplements of amphiphilic matrix, was created. The monolayers was transfered on the solid substrate, what was proved by the AFM and the fluorescence spectroscopy methods. The fluorescence spectra of the LB films with variable numbers of layers was captured.

Integrity Management of Nanocomposite Microstructures Based on Lipids, Polymers and Inorganic Nanoparticles Through Electric Field

Authors: Ermakov A. V., Kim V. P., Chumakov A. S., Gorbachev I. A., Gorin D. A., Savonin A. A., Vidalia I. V., Khomutov G. B., Glukhovsky E. G.

New method of remote group control over permeability and integrity of nanocomposite microstructures of different nature is submitted in this letter. Inorganic nanoparticles are used as a sensitizer to an electric field. The destruction possibility of polymeric microcapsules are shown. The destruction possibility of lipids vesicles on the example of the living cells covered with nanoparticles of gold is shown.

Coatings Formed by Polyionic Assembly and its Electronic Application

Authors: Sergeeva A. S., Gorin D. A.

The work is a review of research in the area of nanostructured thin films formed by Layer-by-Layer self-assembly. This technology allows obtaining the composite coatings and nanomaterials with determined properties. Such structures act as important components of highly integrated devices in various fields of science and technology.

Composite Nonwoven Materials with Microparticles for Regenerative Surgery

Authors: Severyukhina A. N., Svenska Y. I., Gorin D. A.

Composite nonwoven materials with different medical supplements are widely used for regenerative surgery. Majority of these medicines are cytotoxic, therefore precise drug delivery is necessary to decrease toxic effects. We propose novel polymer nanofibrous material impregnated by core–shell microstructures that can provide targeted and controllable release of encapsulated drugs. This biodegradable scaffold system was fabricated using mixing of calcium carbonate microparticles with chitosan solutions followed by electrospinning method.

Nanocomposite Langmuir Layers Based on Molecular Brushes

Authors: Klimova S. A., Inozemtseva O. A., German S. V., Skosyreva T. S., Peganov A. D.

The current state of producing of nanostructured composite materials based on polymers like molecular brushes was described. Experimental results established that using hydrophobic nanoparticles allows to effectively integrate the nanoparticles into the brush polymer monolayer with different length of the side chainsIn this case for composite monolayer formation we need to spread an aliquot of the polymer and nanoparticles simultaneously on the surface of the water subphase using Langmuir–Blodgett technique.

The Impact of External and Internal Electrostatic Fields on Formation of Polyelectrolyte Molecules Coatings

Authors: Stetsyura S. V., Bulanov M. S., Malyar I. V.

The review of scientific articles devoted to preparation of hybrid structures and widespread methods of impact on structure, composition and organic coating properties was carried out. It was demonstrated that difference between chemical and physical methods to modify and to impact is relative due to similar electrostatic interaction under applied external electric fields as well as between molecules and their fragments, i.e. there are internal electric fields in polyelectrolyte’s solution and at interfaces.

Influence of Environment and Temperature on the Luminescent Properties of ZnCdS Nanoparticles

Authors: Skaptsov A. A., Volkova N. V., Galushka V. V., Vidalia I. V., Zakharevich A. M., Konyukhov A. I., Kochubey V. I.

Dependence of the luminescence spectra of the non-stabilized ZnCdS nanoparticles placed in a biological environment on their temperature is investigated. It is shown that the intensity and the position of maximum luminescence of surface defects ZnCdS nanoparticles depends on the temperature and the properties of the biological environment until it is denatured.

Langmuir Monolayers in the Electric Field

Authors: Chumakov A. S., Gorbachev I. A., Ermakov A. V., Kim V. P., Glukhovsky E. G.

An influence of the electric field oriented vertically on the formation process of monolayers. Water and water solutions of inorganic salts are used as a subphase. It’s experimentally shown that the electric field may affect significantly on the monolayers formation of fatty acids: manolayr’s loosening occurs when a deionized water is used as a subphase; manolayr’s consolidation is observed when water solutions of inorganic salts are used as a subphase. An electric field can be significant technology factor of the Langmuir monolayer’s formation process.

Different Types of Surface Enhancement Raman Scattering Platforms and their Applications

Authors: Stetsyura S. V., Gorin D. A.

In this work high sensitive analytical technique surface enhancement Raman scattering (SERS) is considered. The detection of one molecule of substance in solution is possible by this technique. And SERS is noninvasive analytical equipment and for research of bioobjects can be combined with other techniques such as microfluidics or laser tweezers.

Local Cluster Saratov Organized in Framework of the Seventh Framework Programme of Commission of the European Communities «Photonics4Life»

Authors: Bashkatov A. N., Vilensky M. A., Tuchin V. V.

This article is an introduction to the current release, which presents the work of participants in the Workshop of Local Cluster Saratov (LCS) Photonics4Life FP-7 conference held at Saratov State University on March 11, 2011.

OPTICAL BIOMEDICAL DIAGNOSTICS

Authors: Tuchin V. V.
This paper presents an overview on optical biomedical diagnostics. It discusses briefly the history of the problem. The main attention is paid to description of the modern methods of optical medical diagnostics based on spectrophotometry, fluorescence, Doppler spectroscopy, elastic, quasi-elastic and Raman scattering spectroscopies, as well as optothermal and optoacoustic effects.

ANISHCHENKO-ASTAKHOV SELF-SUSTAINED OSCILLATOR AS ONE OF THE BASIC MODELS OF DETERMINISTIC CHAOS

Authors: Anishchenko V. S., Vadivasova T. Е.
In the present review the conditions of appearing chaotic self sustained oscillations are formulated and a radio-technical scheme of a generator realizing these conditions is given. The equations of Anishchenko-Astakhov's generator are derived and analyzed. A special attention is paid to the interrelation between the generator's equations and Theodorchik and Van der Pole classical models.

NONSTATIONARY EXCITATION OF OPEN STRUCTURES

Authors: Davidovich M. V.
The nonstationary theory of excitation for open resonators, waveguides and waveguide transformers has been developed. The open structures which are contained dielectric, magnetic and metallic bodies have been considered.

CLASSICAL ANALYSIS OF RECOMBINATION OF ANTIHYDROGEN IN A STRONG MAGNETIC FIELD

Authors: Serov V. V., Derbov V. L., Vinitsky S. l.
Basing on numerical simulation of classical trajectories, the influence of a strong magnetic field on the rate of the spontaneous radiative recombination of antihydrogen atoms in cold antiproton-positron plasma is theoretically studied under the conditions of the ATHENA and ATRAP experiments carried out in CERN. The effect of the mag netic field is estimated by Monte-Carlo calculation of the change in the cross section of the positron hitting the near-nucleus region with the radius typical for the atomic ground state.

HETEROPHASE SEMICONDUCTORS UNDERACTION OF IRRADIATIONS

Authors: Stetsyura S. V., Rokakh A. G., Serdobintsev A. A.
The history and current state of our heteropfiase photoconducting CdS-PbS films investigations are observed. Films were prepared by the vacuum evaporation method from the materials with limited mu tual solubility. Reasons of increased degradation stability with respect to radiation (in particular y- and electronic irradiations) are found out. Degradation stability is explained by diversion of recombination flow from wide-gap phase to narrow-gap. Radiation stimulated defects also move to narrow-gap phase.

MODELLING THE DYNAMICS OF PHOTONIC CRYSTAL BROAD-AREA SURFACE EMITTING LASER

Authors: Konyukhov A. I.
The lasers beam dynamics in photonic crystal laser is investigated numerically. The decomposition of transverse field distribution in terms of orthogonal modes of photonic crystal structure is used. The relation between the transverse structure of output beam and struc ture of pump region is demonstrated. The modification of the trans verse distribution of the pump allows to control of excitation of se lected transverse mode families. 

CONTEMPORARY PROBLEMS IN MODELING FROM TIME SERIES

Authors: Bezruchko B. P.
Mathematical modeling from discrete sequences of experimental data (time series) is an actively developing field in mathematical statistics and nonlinear dynamics. It started from approximation of a set of data points on a plane with a smooth curve, while currently such empiric models take the form of sophisticated differential and difference equations and are capable of describing even nonlinear oscillatory and wave phenomena. Practical applications of the empiric models are various ranging from future forecasts to technical and medical diagnostics.

S0LIT0NS AND CLUSTERS IN ONE-DIMENSIONAL ENSEMBLES OF INTERACTING BROWNIAN PARTICLES

The survey of the studies results of 1D ensembles dynamics of interacting Browniam particles is presented. Properties of both particles and the Fermi-Pasta-Ulam, Toda, Lennard-Jones, Morse interaction potentials are described. The Langevin equations are exhibited and structures and thermodynamic characteristics which may be extracted from data of a numerical integration of the equations are described. Excitations of phonons, cnoidal waves and solitons in dense ensembles and clusters in ensembles of low density are considered.

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