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Matrix Description of Multicoupled Oscillatory Systems Based on Tridiagonal Matrixes

The matrix description of multicoupled oscillatory systems is presented on the base of tridiagonal matrixes with dominating diagonale elements. The eigenfrequencies of a band-pass filter one calculated for the input node of a differential-gated radiopolarimeter.

Determining Parameters of Planar Capacitors Based of Thin Film Ferroelectric Materials

Experimental results suggest that in the Ni/Ba0.8Sr0.2TiO3/MgO structure with linear sizes of 150 ×150 mm can be realized by planar capacitor elements of variability over a range of capacity from 0.02 pF to 3.0 pF, which increased capacity is achieved by increasing the number of electrode sections.

Mathematical and Computer Modeling of Nonlinear Waves Dynamics in a Physically Nonlinear Elastic Cylindrical Shells with Viscous Incompressible Liquid inside Them

This study focuses on the analysis of nonlinear wave propagation deformations in the elastic physically nonlinear cylindrical shells, containing a viscous incompressible fluid. Wave processes in an elastic cylindrical shell without interacting with fluid were previously studied from the standpoint of the theory of solitons. The developed model describes the processes in the tubes of relatively small diameter compared to the wavelength, such as blood vessels.

Spheroidal Graphite – Unique Morphological Formation of Carbon

Spheroidal graphite is little-known form of graphite. It is known that its presence affects the properties of gray cast iron post, typical steels. Research evidence that the spheroidal graphite is a unique layered spiral system of micro-and nanostructures, the inhomogeneous phase composition, structure and elemental composition with predominantly periodic alternation of closely spaced layers. Such systems can have properties and their combinations significantly different than the individual micro-and nanoparticles and composites based on them.

Vibrational Spectra and Structure of Spinohromes

Modeling calculations of geometric structure and vibrational spectra for spinazarin, ethylspinazarin, echinochrom is carried.

The Study of Possibility of Magnetic Microparticle Deposit in Skin at Superficial Application

The depth of penetration and localization of magnetic microparticles in skin under action of magnetostatic field was studied experimentally. In the study magnetic powder made from intermetallic composition SmCo5 consisting of 37% of samarium and 63% of cobalt was used. Sizes of the particles varied in the range 3–5 μm. As a carrier propylene glycol was used. The experiments were carried out with human skin samples in vitro.

Morphological Changes in the Internal Organs and Implanted Liver Tumor after Intravenous Injection of Gold Nanorods in Rats with Diabetes and Transplanted Tumor

The effects of gold nanorods on the internal organs and the transplanted liver tumor were studied in rats with simulated alloxan diabetes and transplanted liver tumors after intravenous administration. Assessed morphofunctional changes and biodistribution of gold in the internal organs and transplanted liver tumor. The study found that a single intravenous injection of gold nanorods does not cause significant morphological changes in the internal organs and transplanted tumors in rats with alloxan diabetes and transplanted tumor.

Dynamics of Morphological and Biochemical Changes in Laboratory Animals with Transplanted Kidney Cancer after Intravenous Injection of Gold Nanoshells

The effect of intravenously injected nanoshells on white outbred male rats with transplanted tumor of kidney cancer was studied. The blood biochemical parameters and morphological changes in the rat internal organs were examined during 24 h after nanoparticle injection. The most pronounced changes were observed 45 min – 2 h after nanoparticle injection and were reversible.

Modelling Calculations of Vibrational Spectra for Substituted Benzoic Acid

On the base of modeling calculations of geometric and electronic structure for substituted benzoic acid the parameters of adiabatic potential are investigated.

Parametric Gain Calculation in Photonic Crystal Fiber

Signal wave parametric gain was calculated in photonic crystal optical fiber. Photonic crystal fiber structure was optimized for broadband parametric gain. It is shown, that gain bandwidth for photonic-crystal fiber optical parametric amplifier could be more than 400 nm. Spectral changings in parametric gain due to modulation of photonic crystal waveguide cross-section was studied.

Optical Transient Nutation in Frequency-modulated cw Laser Beams in Resonant Self-Action Conditions

On the basis of numerical simulations an optical transient nutation is investigated. This effect is developed on high modulation amplitude of frequency-modulated cw laser beam propagating in resonance conditions. At modulation periods comparable with the atomic relaxation times the time dependence of the output intensity exhibits the combined manifestations of optical nutation and resonance self-action.

Analysis of Fruit Juices Using a Hollow Core Photonic Crystal Waveguides

The aspects of application of the hollow core photonic crystal waveguides for spectroscopic analysis of liquid medium were considered. The possibility of using these structures for analysis of a fruit juice was evaluated. The principles of processing of photonic crystal waveguide transmission spectra, which is sensitive to quality of juice, its composition, and main component concentration, were revealed.

The Perspective Slow-wave Systems of Terahertz Band for TWT

In this paper the review of terahertz perspective slow-wave systems is presented for TWT.

The methods of modeling have been considered and some numerical results are presented.

Calculation of Structure and IR Spectrum of the 2,3-di-O-nytro-methyl-β-D-Glucopyranoside Molecule by Density Functional Method

Structural-dynamic models of the 2,3-di-O-nytro-methyl-β-Dglucopyranoside molecule are constructed by density functional method in basis 6-31G(d). Energies, structures, dipole moments, polarizabilities, frequencies of normal modes in harmonic approximation and IR intensities have been calculated. Interpretation of IR absorption spectrum is presented in range 600–3700 cm–1. Advantages of model, which was constructed, compared with model, which bases on using valence-force field method and valency-optical theory, are discussed.

Visualization of Penetration of TiO2 Nanoparticles into Tooth Tissues Samples Using Optical Coherence Tomography

Penetration of nanoparticles into the tooth tissues is of significant interest in solving the problems, related to the reduction of the tooth sensitivity, enamel strengthening and restoration and cosmetic bleaching. In the present paper we demonstrate the possibility to use optical coherent tomography for visualization of penetration of nanoparticles into the tooth tissues.

Contrasting in Optical Coherence Tomography Imaging of Liver by Nanoparticles

Possibility of improvement of inner liver structure visualization in optical coherent tomograms by increasing their contrast due to administration of titanium dioxide nanoparticles in various suspensions and at various methods of delivering of the particles into the tissue is considered. Values of contrast of inner liver structures in vitro are obtained.

The Study of Nail Bed Microcirculation by Laser SpeckleImaging Technique

The applicability of laser speckle contrast analysis technique for study of nail bed microcirculation parameters was investigated. Parameters and their dynamics were considered using calibration data obtained with biotissue phantom. Optimal conditions of formation and registration of speckle images were discussed and program for adaptive operation and processing was presented. The data of microscopic observations of nail bed capillary network was used to verify the results of speckle visualization.

Investigation of «Erythrocyte – Plasma» Complex in Native Human Blood Slide Using WhiteLight FullField Microinterferometry

Morphofunctional properties of erythrocytes in native blood slide of coronary heart disease patients are investigated using white light fullfield microinterferometry. Three dimensional images and surface profiles of complex «single RBC – surrounding blood plasma» are shown. Dynamic of slope angle of the plasma near the RBC during standardized intravenous glucose load is explored. The dynamic of patients with coronary heart disease is compared with one of patients with coronary heart disease and diabetes mellitus.

Effect of Spectral Properties of Image Sensor on Interference Experiment

Influence of spectral properties of monochrome image sensor on spectrum of detecting radiation in fullfield lowcoherence microinterferometer is investigated. Dependence of interference pulse shape and period of interference fringes on the spectrum is shown. Simulated results and experimental measurements of integral transmission spectrum of Linnik microinterferometer with the silicon monochrome image sensor and thermal light source are presented.

Dynamic and Spectral Characteristics of Time Series Describing Pulse Wave Velocity

We analyze the dynamic and spectral characteristics of the signals that reflects the rapid changes in pulse wave velocity (PWV). We describe the characteristics of PWV signal in the high frequency HF range (from 0.1 to 0.5 Hz) and suggest a simple model that illustrates our hypotheses.

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