Search articles

Prospects For Application of Upconversion Particles NaYF4:Er,Yb for Phototherapy

Authors: Sagaidachnaya E. A., Yanina I. Y., Kochubey V. I.

Background and Objectives: Functionalized upconversion particles allow for photodynamic and photothermal therapy of tumor with simultaneous temperature monitoring and visualization of the area of treatment. Upconversion particles can increase the depth of therapeutic effects due to the high penetration depth of the required excitation radiation. That is why they are a promising material for the combined phototherapy and simultaneous monitoring of biological tissue heating.

Optical Clearing as Method to Increase the Depth of Nanoparticles Detection in the Skin with OCT-Visualization

Authors: Zaytsev S. M., Bashkatov A. N., Tuchin V. V., Genina E. A.

Background and Objectives: Nanoparticles of titanium dioxide are now widely used both for the creation of sunscreen filters, and as carriers of drugs. One of the ways of transepidermal delivery of these nanoparticles to the dermis of the skin is their penetration into the hair follicles. However, optical control of the filling of follicles with nanoparticles is rather difficult due to strong light scattering in the skin.

On the Possibility of Stabilization of a Contracted State after Riboflavin/UV Cross-Linking of Collagenous Tissue in a Partially Dehydrated State

Authors: Shvachkina M. E.

Background and Objectives: The method of riboflavin/UV collagen cross-linking is widely used to strengthen the corneal stroma in the treatment of keratoconus and is of considerable interest as a possible method to improve the biomechanical property of the sclera in the treatment of myopia. Regarding the application of this method to the sclera, one of the important problems is the rapid decrease in the intensity of UV radiation due to scattering as it propagates into the tissue.

Application of Thermal Imaging Diagnostics in Assessment of Inflammatory Response after Sclerotherapy in Patients with Lower Limb Varicose Disease

Authors: Chabbarov R. G., Ostrovsky N. V., Skripal A. V., Sanbaev A. K., Usanov A. D., Mayskov D. I.

Background and Objectives: Sclerotherapy of the lower extremities veins refers to one of the promising methods of treating patients with varicose veins. However, at present, there are no effective methods for assessing the condition of sclerotic veins during sclerotherapy.

The Graphene Based Terahertz Transistor

Authors: Davidovich M. V., Glukhova O. Е., Slepchenkov M. М.

Background and Objectives: Due to the lack of a substantial energy gap in graphene nanoribbons there are difficulties to create a fast-switching transistors for digital circuits using them. In a number of recent works, the usage of graphene nanoribbons in tunneling transistors, field effect transistors, transistors with negative resistance and in generators with pumping has been proposed for amplification of analog signals.

Magnonic Logic Devices

Authors: Khitun A. G., Kozhanov A. Е.

Background and Objectives: There is a big impetus for the development of novel computational devices able to overcome the limits of the traditional transistor-based circuits. The utilization of phase in addition to amplitude is one of the promising approaches towards more functional computing architectures. In this work, we present an overview on magnonic logic devices utilizing spin waves for information transfer and processing.

Magnetic Properties of Textured NiFe(111) and NiFe(200) Films

Authors: Dzhumaliev А. S., Nikulin Y. V.

Thickness dependencies (d м 20–370 nm) of the saturation magnetization 4πМ, the ferromagnetic resonance linewidth ΔH, the coercivity field Hc and the shape of hysteresis loops were investigated for Ni80Fe20 (NiFe) films with (200) texture. The thickness dependencies of magnetic parameters for NiFe(200) films were compared with the dependencies 4πМ(d), ΔH(d) and Hc(d) for NiFe(111) films with strong (111) texture and polycrystalline NiFe films.

Influence of Argon Pressure on Texture and Microstructure of Cobalt Films Produced by Dc-Sputtering

Authors: Dzhumaliev А. S., Nikulin Y. V.

Background and Objectives: The development of methods of textured Co film formation is of practical interest in the field of creating media with perpendicular recording of information or lateral spin-valve structures. Despite a rather wide study of the growth conditions effects on the microcrystalline structure of sputtered cobalt films, the possibility of changing the texture and microstructure via a change of the gas pressure has not been discussed.

Phonon-Drag Thermopower in a Quantum Wire with Parabolic Confinement Potential for Electrons

Authors: Hasanov K. А., Huseynov J. I., Dadashova V. V., Nabiyev A. E., Abbasov I. I.

Background and Objectives: A quantitative theory of the phonondrag thermopower for one-dimensional degenerate electron gas in a quantum wire with parabolic confinement potential is presented. The temperature gradient is directed along the axis of the quantum wire. Due to the confinement, the energy spectrum and the wave function of the electron change substantially. It is assumed that the Fermi level is located between the zeroth and the first of the size quantization.

Carbon Film Nanocomposite for High-Current Field Electron Sources

Authors: Yafarov R. K., Shanygin V. Y., Nefedov D. V.

Background and Objectives: Requirements and problems are formulated when creating cathode materials for high-current emission electronics. It has been shown that to create autocathodes with a current density of up to 100 A/cm2 and above, the development of new nanostructured carbon materials with a surface density of nanodiamond edges of not less than 106–108 cm-2 is necessary. Using a non-equilibrium low-pressure microwave plasma, the regions of regimes for obtaining carbon film coatings containing the diamond and graphite phases in various volume ratios are determined.

Influence of Plasma-Chemical Modification of the Surface on Transverse Electron Transport and VAC of Silicon MIS Structures

Authors: Yafarov R. K., Nefedov D. V.

Background and Objectives: The laws governing the modification of the current-voltage characteristics of the metal-insulatorsemiconductor structures due to the formation of embedded surface potentials are investigated. Surface potentials are formed when an atomically clean surface of silicon crystals is produced using microwave plasma micromachining. The aim of the work is to study the effect of plasma micromachining in various chemically active gaseous media on the properties of silicon MIS structures.

Detection of Terahertz Radiation in Graphene Structure under Conditions of Strong Spatial Inhomogeneity of the Plasmon Electric Field

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

Background and Objectives: Research of terahertz (THz) wave rectification in graphene shows the increase of the rectified current in p-n graphene structures relatively to graphene having only n- or p-type of conductivity. The p-n junctions in graphene may be created by both a chemical or electrical doping of graphene. There were discussed several physical mechanisms for wave rectification in graphene structures, that are the photothermoelectric effect, Drude heating of carriers by THz radiation and nonlinear plasmonic effects.

Surface Electromagnetic Waves in the of Optical Range (Surface Plasmon Polaritons – Spps): Their Properties and Applications

Authors: Nazvanov V. F.

Surface plasmon polaritons (SPPs) are electromagnetic excitations, in wich electromagnetic field in dielectric is coupled to collective electron oscillation in metal, and propagate along and is tightly bound to metal/dielectric interfaces. First, we present an overview of SPPs in the optical range and their applications in optoelectronics and sensorics. We further present the main research results achived by the author in this area.

The Manifestation’s Research of the Pair Association in the Pyridine’s Ir-Spectrums by the Matrix Isolation Technique

Authors: Berezin K. V., Nechaev V. V., Kozlov O. V., Novoselova A. V., Chernavina M. L., Berezin V. I., Berezina M. K., Novoselov V. V.

The calculation of structure, frequencies of normal fluctuations and the strips intensity in IR-spectrums of five dimer of pyridine with hydrogen communication  has been performed by the matrix solation technique B3LYP/6-311+G (d, p). The number’s modeling of the difficult oscillatory contours in the pyridine’s IR-spectrum was executed taking into account the intermolecular interaction.

The influence of Morphology, Conditions of Production and External Effects on Nanoparticles’ (in Terms of Iron) Dielectric Properties

Authors: Belenko D. I., Therin D. V., Tozkoparan O., Ildyrym O., Galushka V. V., Dinker I., Dobrinsky E. K., Ellerman Y., Venig S. B.

It was shown that the complex research of iron nanoparticles properties by different methods, supplemented each other, permit to receive the data about the interior sizes of nanoparticles, a number of physical properties of particles, their dependence on frequency and changes produced by various influences. It was found that the conductivity of nanoparticles changed under the square dependence σ = σo*ω2.

Microwave Absorption Spectra and Resonance Frequencies of a «Magnetic Nanocomposite Coating – Microstrip Line» Structure

Authors: Voronin D. V., Beginin E. N.

This paper aims to look into microwave absorption spectra of «mag-netic nanocomposite coating – microstrip line» structure, containing magnetite Fe3O4 nanoparticles. The resulted spectra allowed to define the specific resonance frequencies of the structure under investiga-tion and to figure out the material parameters of the nanocomposite coating, that are, an effective magnetization, a volume fraction of magnetic nanoparticles in the coating as well as a magnetic crystal-line anisotropy filed.

Fluorescent Properties of Quantum Dots During Silanization Process

Authors: Goftman V. V., Vostrikova A. M., Goryacheva I. Y.

Quantum dots (QDs) are fluorescent semiconductor nanoparticles with unique optical properties. For bioapplication QDs have to be water-soluble. Here we describe one of common hydrophilization approaches – ligand exchange on silica precursors molecules and investigate fluorescent properties during this process.

Тhе Quasipotential Approach to the Syperfine Splitting of Muonic Hydrogen and Positronium

Authors: Boykov A. A., Baykova N. A.

For the description of the two-partial atoms spectrum in quasipotential approach the relativistic amplitude is used. The interrelation of scattering amplitude expressions, corresponding to quantovoelektrodinamic corrections in various orders is traced. Arising from the accounting of delay effect the additional logarithmic corrections of the sixth order to the constant of fine structure in the bound level superfine shift are analyzed.

Creating and Fluorescence of the Multilayer Langmuir – Blodgett Films of CdSe/CdS/ZnS Quantum Dots

Authors: Gorbachev I. A., Shtykov S. N., Glukhovsky E. G.

Multilayered structures composed by Langmuir – Blodgett films of CdSe/CdS/ZnS quantum dots functionalized by oleic acid and fluorescent at 525 and 631 nm were prepared and studied by fluorescent spectroscopy. It was shown that fluorescent spectra of the nanosized multilayered film consisting of different QD layers have complex character and can be rearranged with relative positions of QD layer and laser beam that open possibility to operate the fluorescent intensity of every QD layer.

Range of Gamma Quanta in the Beryllium Target

Authors: Zalesny G. N., Klochkov M. A.

Changes of an initial brake range of gamma quanta in a sample are analysed. It is shown that the main mechanism influencing g quanta range form in a sample of beryllium is Compton’s effect. In work this amendment is considered in the analysis of an exit of photoneutrons. However unlike the models considered in other works at the accounting of Compton dispersion parametrization isn’t used.

Pages