Effect of Resonance Radiation Trapping on the Excited State Densities in Free-Burning Arc Plasmas

Modern arc models takes into account collisional-radiative schemes for better agreement with experiment [1]. Radiation transport phenomena play an important role in redistribution of excited species densities. Influence of resonance radiation transport on spatial distribution of excited atoms in argon arc plasma was studied by numerical model. Solution of the Holstein-Biberman equation was based on the matrix method [2]. Results are compared with conventional effective lifetime approach

Spectroscopic Study of Arc Temperature Profiles of a Switching-off Process in a Model Chamber

A model chamber was applied to emulate a switching-off process which is very similar to those in real high-voltage circuit-breakers. The arc between moved W-Cu electrodes through a PTFE nozzle in SF6 was considered. Transparent windows in the chamber wall and a slit in the nozzle enabled an optical in-vestigation of the arc cross section several milliseconds before current zero. The side-on radiance of fluo-rine atom lines has been measured. Considering rotational symmetry of the arc the corresponding radial emission coefficients have been determined. Radial temperature profiles have been obtained with uncer-tainties below 10% considering change of window transmission and optical depth of the line radiation. The experimentally determined temperature profiles are used to validate a CFD simulation of the switch-ing-off process in the model chamber

Международно-правовой режим регулирования судоходства и задача развития национального судоходства

Горчаков С. В. Международно-правовой режим регулирования судоходства и задача развития национального судоходства / С. В. Горчаков // Міжнародні читання з міжнародного права пам’яті професора П.Є. Казанського : матер. третьої міжнар. наук. конф. (м. Одеса, 2–3 листопада 2012 р.) / відп. за випуск М. І. Пашковський ; НУ «ОЮА». – Одеса : Фенікс, 2012. – С. 507-512.В своей работе автор статьи пришел к выводу, что конструируя национальный правовой режим для развития национального судоходства в Украине следует придерживаться принципов романо-германской системы права, а именно, адресовать государственную поддержку не вещам (судам, зарегистрированным во втором реестре), а лицам, т. е. украинским владельцам и операторам судов независимо от флага (по примеру некоторых стран)

Interaction of a free burning arc with regenerative protective layers

The possible use of protective layers made of ceramic powders for walls in thermal plasma applications is studied. A stable free burning arc of currents up to 5 kA between copper- tungsten electrodes is used to analyse the arc interaction with samples coated by mixtures of CaCO3, MgCO3, and Mg(OH)2 with plaster. By means of optical emission spectroscopy the maximum arc temperature and the radiation impact on the surfaces are estimated to be around 15000 K and 20 MWm-2, respectively. Thermographic measurements confirm the efficient protection of substrates by all layer materials. Layers containing CaCO3 lead to the lowest heating of ceramic samples which may be caused by a strong evaporation of the layer material

A technology of drinking water decontamination from radon and its decay products

Underground water is one of the main sources of radon for households. This article focuses on the estimation and removal of radon from underground water using the technology and inorganic sorbents developed by EKSORB Ltd., Russia for liquid radioactive waste treatment in the nuclear power industry. The article presents the results of tests of a system for the removal of radon and radon daughters from water patented by EKSORB. This is achieved by filtering water through RATZIR sorbent, followed by periodic load regeneration. Over a period of three years, the plant is successful in removing radon from the water that had an initial radon content of approximately 1500 Bq/L to less than 60 Bq/L, without releasing radon to indoor/outdoor air. © 2020 Igor Voinov et al., published by Sciendo 2020

Investigation of a Multi-Chamber System for Lightning Protection at Overhead Power Lines

A multi-chamber system with composite electrodes fitted into silicone rubber has been recently proposed for lightning protection of power lines. The arc extinction during a current pulse in the arc chamber has been studied. Optical emission spectroscopy and high speed imaging used in experiments allowed to es-timate plasma temperature and velocity of the jet. Erosion coefficients for electrode materials were esti-mated. Investigations of different materials of the arc chamber were carried out

Environmental monitoring of natural waters in Krasnodar and Stavropol Territories

The environmental monitoring of natural waters in Krasnodar (Uspensky and Novokubansky districts) and Stavropol (Kochubeyevsky District) Territories was conducted. In the course of study, various elements and compounds harmful to animals and humans, which exceed maximum permissible concentrations, were identified

MORPHOLOGICAL CHARACTERISTICS OF TISSUE MICROREGION OF THE THYROID GLAND AT EXPERIMENTAL HYPOTHYROIDISM

Research purpose was to study the structures of the tissue microregion of the thyroid gland at an experimental hypothyroidism. Material and methods. The hypothyroidism model was created by mercazolilum intake at a dose of 5 mg/100 g of body mass for a month. The structure of tissue area (follicle, thyrocyte, interfollicular space) with morphometry and calculation of the integral indicators of the thyroid gland functional activity have been investigated by the light-optical and ultrastructural methods. Results and discussion. The morphophysiological structure of the thyroid gland is a tissue microregion. It unites a group of follicles and interfollicular space. The structure of the tissue miroregion have features of structural response to merkazolilum intake. The thyrostatic remedy changes the follicular organization of the thyroid gland to the predominance of small and medium follicles with signs of alteration. Thyrocytes have expansion and deformation of the granular endoplasmic reticulum cisterns, formation of intracellular colloid, reduction in the number of lysosomes and mitochondrions with their disorganization. The ratio of the area of the follicular epithelium, colloid and stroma changes at hypothyroidism. The portion of interstitial increases, there is an accumulation of tissue fluid because of weakening of a lymphatic drainage. Blood and lymphatic microvessels react by reducing the volume density to mercazolilum intake. Conclusion. The merkazolilum thyreostatics effects on morphology and metabolic and transport processes in tissue microregion. It testifies to decrease of thyroid function and the creation of hypothyroidism adequate model

Vaccination with DNA plasmids expressing Gn coupled to C3d or alphavirus replicons expressing Gn protects mice against rift valley fever virus

Background: Rift Valley fever (RVF) is an arthropod-borne viral zoonosis. Rift Valley fever virus (RVFV) is an important biological threat with the potential to spread to new susceptible areas. In addition, it is a potential biowarfare agent. Methodology/Principal Findings: We developed two potential vaccines, DNA plasmids and alphavirus replicons, expressing the Gn glycoprotein of RVFV alone or fused to three copies of complement protein, C3d. Each vaccine was administered to mice in an all DNA, all replicon, or a DNA prime/replicon boost strategy and both the humoral and cellular responses were assessed. DNA plasmids expressing Gn-C3d and alphavirus replicons expressing Gn elicited high titer neutralizing antibodies that were similar to titers elicited by the live-attenuated MP12 virus. Mice vaccinated with an inactivated form of MP12 did elicit high titer antibodies, but these antibodies were unable to neutralize RVFV infection. However, only vaccine strategies incorporating alphavirus replicons elicited cellular responses to Gn. Both vaccines strategies completely prevented weight loss and morbidity and protected against lethal RVFV challenge. Passive transfer of antisera from vaccinated mice into naïve mice showed that both DNA plasmids expressing Gn-C3d and alphavirus replicons expressing Gn elicited antibodies that protected mice as well as sera from mice immunized with MP12. Conclusion/Significance: These results show that both DNA plasmids expressing Gn-C3d and alphavirus replicons expressing Gn administered alone or in a DNA prime/replicon boost strategy are effective RVFV vaccines. These vaccine strategies provide safer alternatives to using live-attenuated RVFV vaccines for human use. © 2010 Bhardwaj et al