Characterization of high-temperature PbTe p-n junctions prepared by thermal diffusion and by ion-implantation

We describe here the characteristics of two types of high-quality PbTe p-n-junctions, prepared in this work: (1) by thermal diffusion of In4Te3 gas (TDJ), and (2) by ion implantation (implanted junction, IJ) of In (In-IJ) and Zn (Zn-IJ). The results, as presented here, demonstrate the high quality of these PbTe diodes. Capacitance-voltage and current-voltage characteristics have been measured. The measurements were carried out over a temperature range from ~ 10 K to ~ 180 K. The latter was the highest temperature, where the diode still demonstrated rectifying properties. This maximum operating temperature is higher than any of the earlier reported results. The saturation current density, J0, in both diode types, was ~ 10^-5 A/cm2 at 80 K, while at 180 K J0 ~ 10^-1 A/cm2 in TDJ and ~ 1 A/cm2 in both ion-implanted junctions. At 80 K the reverse current started to increase markedly at a bias of ~ 400 mV for TDJ, and at ~550 mV for IJ. The ideality factor n was about 1.5-2 for both diode types at 80 K. The analysis of the C-V plots shows that the junctions in both diode types are linearly graded. The analysis of the C-V plots allows also determining the height of the junction barrier, the concentrations and the concentration gradient of the impurities, and the temperature dependence of the static dielectric constant. The zero-bias-resistance x area products (R0Ae) at 80 K are: 850 OHMcm2 for TDJ, 250 OHMcm2 for In-IJ, and ~ 80 OHMcm2 for Zn-IJ, while at 180 K R0Ae ~ 0.38 OHMcm2 for TDJ, and ~ 0.1 OHMcm2 for IJ. The estimated detectivity is: D* ~ 10^10 cmHz^(1/2)/W up to T=140 K, determined mainly by background radiation, while at T=180 K, D* decreases to 108-107 cmHz^(1/2)/W, and is determined by the Johnson noise

Vermicompost effect on the trace elements distribution in the luvic chernozem of the Krasnoyarsk forest-steppe

n the field experiment (2016-2018) in the conditions of the Krasnoyarsk forest-steppe the number of trace elements mobile forms were determined and the effect of soil organic matter and increasing doses of vermicompost on their distribution in luvic chernozem was studied. It is established that the studied vermicompost does not pollute the soil, which allows its widespread use in agriculture. The correlation and regression analysis obtained linear regression equations that reflect the relationship of the chemical element and organic matter in the soil after using increasing doses of vermicompost adequately. Elements with positive correlation and high significance level include Mn, Cu, Co and Zn

Competence and Professional Skills in Training Future Specialists in the Field of Physical Education and Sports

The relevance of the problem is determined by the need to understand the further strategy of improving the training of physical education and sports specialists. The purpose of the article is to study the problem of correlation between the notions of “competence” and “professional skill” in the context of the formation of a specialist in the field of physical education and sports. The study of the relationship between the notions of “competence” and “professional skill” was conducted on the basis of an array of special literature on the competent approach to training of physical education and sports specialists, including more than 200 sources published in different countries. The article analyses negative trends in the content of training future specialists in the system of higher professional physical education based on a competence approach. The acme-culturological approach for improving the professional training of future specialists is proposed and tested, the stages of formation of professional skills of future specialists in the training process are presented. There is a need to focus on the identified features of professional training of young people to professions in the field of physical education and sports. The proposed system of professional training of future specialists of physical education and sports on acme-culturological bases directs teachers to improve the quality of training graduates in their future professional activities

Theory of current-driven motion of Skyrmions and spirals in helical magnets

We study theoretically the dynamics of the spin textures, i.e., Skyrmion crystal (SkX) and spiral structure (SS), in two-dimensional helical magnets under external current. By numerically solving the Landau-Lifshitz-Gilbert equation, it is found that (i) the critical current density of the motion is much lower for SkX compared with SS in agreement with the recent experiment, (ii) there is no intrinsic pinning effect for SkX and the deformation of the internal structure of Skyrmion reduces the pinning effect dramatically, (iii) the Bragg intensity of SkX shows strong time-dependence as can be observed by neutron scattering experiment.Comment: 4 pages, 3 figure

Study of the dosing tissue distraction clinical efficacy in the soft tissue defects treatment of various etiologies in the lower extremities

Justification. The most methods of extensive skin and soft tissue defects are aimed at accelerating wound healing  and preventing infectious complications. To improve the effectiveness of such defects treatment, a method of dosed tissue distraction (MDTD) is used, consisting in the application of a continuously acting load to the area of healthy soft tissue in close proximity to the wound defect.Purpose. It performed the evaluation of the medico-social  effectiveness of the introduction into clinical practice of developed methods and devices for implementing MDTD in  the treatment of skin and soft tissue defects of the extremities.Methods. 407 patients were treated with wound defects of  the extremities, which were divided into two groups: the main group – 198 patients in whose treatment MDTD was applied using original methods and devices; comparison group – 209 patients, in whose treatment standard treatment methods were applied. Comparison of the long-term results of treatment according to the frequency of repeated operations, complications, indicators of quality of life, frequency of disability.Results. The use of MDTD is characterized by better performance compared with the use of standard approaches. There is a decrease in the frequency of performing reconstructive plastic surgery after inpatient treatment (9–10 times), remote complications by 2.6 times, a reduced value of the Vancouver scale (by 28.8%), quality of life indicators higher levels. The use of the proposed approach is characterized by a shorter duration of treatment (by 26.0%), duration of disability (1.4 times), cases of disability (2.2 times).Conclusion. The use of MDTD is characterized by high medical and social efficiency, allows to reduce the cost of treating extensive skin and soft tissue defects by reducing the length of hospitalization, the frequency of repeated rehabilitation and reconstructive operations, accelerated recovery of patients, improving the quality of life and reducing the incidence of disability

Dynamics of Gaseous Disks in a Non-axisymmetric Dark Halo

The dynamics of a galactic disk in a non-axisymmetric (triaxial) dark halo is studied in detail using high-resolution, numerical, hydrodynamical models. A long-lived, two-armed spiral pattern is generated for a wide range of parameters. The spiral structure is global, and the number of turns can be two or three, depending on the model parameters. The morphology and kinematics of the spiral pattern are studied as functions of the halo and disk parameters. The spiral structure rotates slowly, and its angular velocity varies quasi-periodically. Models with differing relative halo masses, halo semi-axis ratios, distributions of matter in the disk, Mach numbers in the gaseous component, and angular rotational velocities of their halos are considered.Comment: 22 pages, 11 figure

Spin physics with antiprotons

New possibilities arising from the availability at GSI of antiproton beams, possibly polarised, are discussed. The investigation of the nucleon structure can be boosted by accessing in Drell-Yan processes experimental asymmetries related to cross-sections in which the parton distribution functions (PDF) only appear, without any contribution from fragmentation functions; such processes are not affected by the chiral suppression of the transversity function $h_1(x)$. Spin asymmetries in hyperon production and Single Spin Asymmetries are discussed as well, together with further items like electric and magnetic nucleonic form factors and open charm production. Counting rates estimations are provided for each physical case. The sketch of a possible experimental apparatus is proposed.Comment: Presented for the proceedings of ASI "Spin and Symmetry", Prague, July 5-10, 2004, to be published in Czech. J. Phys. 55 (2005