Mechanism for flux guidance by micrometric antidot arrays in superconducting films

A study of magnetic flux penetration in a superconducting film patterned with arrays of micron sized antidots (microholes) is reported. Magneto-optical imaging (MOI) of a YBCO film shaped as a long strip with perpendicular antidot arrays revealed both strong guidance of flux, and at the same time large perturbations of the overall flux penetration and flow of current. These results are compared with a numerical flux creep simulation of a thin superconductor with the same antidot pattern. To perform calculations on such a complex geometry, an efficient numerical scheme for handling the boundary conditions of the antidots and the nonlocal electrodynamics was developed. The simulations reproduce essentially all features of the MOI results. In addition, the numerical results give insight into all other key quantities, e.g., the electrical field, which becomes extremely large in the narrow channels connecting the antidots.Comment: 8 pages, 7 figure

Using of science technologies for mining machinery constructions' strength improvement

Recommendations for strengthening the brake construction in accident dangerous areas of fatigue destruction were developed. Computer modeling was made using the ANSYS program that helps to visualize stained condition of the construction for further practical testing of the strength and reliability improving technology of mining elevating machines' constructions, which are being in a long-term use, with a help of the strengthening elements. A way of construction strengthening, which eliminates the possibility of further fatigue destruction of the brake system elements, because of the load cycle in exploitation process

Practical thermodynamics of Yukawa systems at strong coupling

Simple practical approach to estimate thermodynamic properties of strongly coupled Yukawa systems, in both fluid and solid phases, is presented. The accuracy of the approach is tested by extensive comparison with direct computer simulation results (for fluids and solids) and the recently proposed shortest-graph method (for solids). Possible applications to other systems of softly repulsive particles are briefly discussed.Comment: Published in J. Chem. Phy

Remote ultra-wideband tomography of nonlinear electronic components

The efficiency of using ultra-wideband (UWB) signals for nonlinear radar is investigated. In the case at hand, it is necessary to see, based on scattered field disturbances, whether nonlinear inclusions are present in the field of view. The solution suggested is to compare the shapes of UWB signals reflected from the probe area under two conditions: an additional generator irradiating the probe area by intense monochromatic radiation is switched on and off. If a nonlinear electronic component is present in the probe area, the reflected UWB signals differ in shape. Thus, the difference in the shapes of the signals indicates the presence of a component with a nonlinear characteristic

Interaction between superconducting vortices and Bloch wall in ferrite garnet film

Interaction between a Bloch wall in a ferrite-garnet film and a vortex in a superconductor is analyzed in the London approximation. Equilibrium distribution of vortices formed around the Bloch wall is calculated. The results agree quantitatively with magneto-optical experiment where an in-plane magnetized ferrite-garnet film placed on top of NbSe2 superconductor allows observation of individual vortices. In particular, our model can reproduce a counter-intuitive attraction observed between vortices and a Bloch wall having the opposite polarity. It is explained by magnetic charges appearing due to discontinuity of the in-plane magnetization across the wall.Comment: 4 pages, 5 figure

РЕЗОНАНСНЫЕ ШИРОТНО-ИМПУЛЬСНЫЕ ПРЕОБРАЗОВАТЕЛИ

Circuit constructions of the DC-to-DC converter with an operated exchange of energy between reactive elements, namely the DC-to-DC converter of an output voltage step-up and step-down (buck-boost) type were described. In the case of the construction of the converter with an inductive storage element, DC-to-DC converter has half the number of reactive elements. Then in the environment of Simuling of the Matlab program a computer model for the specified DC-to-DC converter was created. With its help the operating characteristic was designed and analyzed. By measurements presented on screens of Display blocks, values of currents and voltages on the DC-to-DC converter elements and also all necessary power indicators on entrance and output clips of the converter were determined.Описаны схемные построения широтно-импульсных преобразователей (ШИП) с управляемым обменом энергии между реактивными элементами, а именно ШИП типа понижающе - повышающие выходное напряжение. Для случая построения преобразователя с индуктивным накопительным элементом, ШИП содержит вдвое меньшее число реактивных элементов. В дальнейшем в среде Simuling программы Matlab для указанного ШИП создана компьютерная модель. С её помощью построена и проанализирована регулировочная характеристика. По данным измерений, представленных на экранах блоков Display, определены величины токов и напряжений на элементах ШИП, а также все необходимые энергетические показатели на входных и выходных зажимах преобразователя

Overexpression of MRPS18-2 in cancer cell lines results in appearance of multinucleated cells

Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Human mitochondrial ribosomal protein MRPS18-2 (S18-2) is encoded by a cellular gene that is located on the human chromosome 6p21.3. We discovered that overexpression of the S18-2 protein led to immortalization and de-differentiation of primary rat embryonic fibroblasts. Cells showed anchorage-independent growth pattern. Moreover, pathways characteristic for rapidly proliferating cells were upregulated then. It is possible that the S18-2 overexpression induced disturbance in cell cycle regulation. We found that overexpression of S18-2 protein in human cancer cell lines led to an appearance of multinucleated cells in the selected clones.publishersversionPeer reviewe

Effect of different oral doses of glucose on the blood serum content of serotonin in rats

The analysis of the effect of different doses of oral glucose content of serotonin in blood serum of rats. The increasing content of serotonin in blood serum of rats with diabetes and with the administration of glucose. The increase in the studied parameters in the serum of the control group of animals under conditions of a glucose. It is concluded that glucose has a direct positive effect on the endogenous flow of serotonin into the bloodstream

Refining of metal melts by filtration method

The article describes the prerequisites of filtration refining of metal melts. When filtering the liquid metals the refining effect is caused by the deposition on the filter surface of suspended non-metallic particles in the melt, and by the release of the non-metallic phase directly from the melt. Along with this the mechanism of melt refining from a superequilibrium dissolved impurity is realized when filtering as a result of the reaction course of chemical binding of the impurity element

Planck pre-launch status: HFI beam expectations from the optical optimisation of the focal plane

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which will map the cosmic microwave background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data. We present a detailed description of the optical design of the High Frequency Instrument (HFI) together with some of the optical performances measured during the calibration campaigns. We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to ideal telescope elements, and on their significance for the HFI data analysis procedure