Investigation of plasma-slag processes in special and ladle electrometallurgy of steel

Theoretical analysis made it possible to consider advantages of the progressive technology of steelmaking and determine specificity of main processes of the plasma-slag metallurgy, calculate partial pressure of the components and composition of the vapor-gaseous phase above slag of the fluorite--lime and lime--alumina--silicate systems. Experimental investigations allowed specifying some peculiarities of pyrometallurgical reactions in the gas (plasma)--slag--metal system in melting of ball bearing and stainless steels, low carbon iron, high carbon ferrochromium, and alloying of iron by chromium in case of application of the plasma-arc models as heat sources.Теоретический анализ дал возможность рассмотреть достоинства прогрессивной технологии сталеплавильного производства, определить специфику основных процессов плазменно-шлаковой металлургии, рассчитать парциальное давление компонентов и состав парогазовой фазы над шлаками флюорито-известковой и известково-глиноземно-силикатной систем. Экспериментальные исследования позволили уточнить некоторые особенности пирометаллургических реакций в системе газ (плазма)-шлак-металл при выплавке шарикоподшипниковой и нержавеющих сталей, низкоуглеродистого железа, высокоуглеродистого феррохрома и легирования железа хромом при использовании в качестве источника теплоты плазменно-дуговых моделей

School Bullying: the Internal Issue and Means for Management

This article provides an overview of national and foreign works on the problem of bullying, which is described as a complex phenomenon. It is a result of systemic pressure and growing intra-group tension on the one hand, and as an effect of victimization and use of violence &mdash; on the other. The complex structure of bullying makes high demands on anti-bullying programs. It should deal with systemic group features and students' personal characteristics. The text provides the analysis of short-term anti-bullying programs. An anti-bullying program plan is proposed, based on the KiVa program, taking into account the specifics of the education system in Russia.</p

Simulating a scintillation fiber detector of the activities of ionizing radiation sources

Computer simulation results are presented for a fiber sensor based on the Saint-Gobain Crystals BSF-60 scintillation fiber aimed to measure the activities of sources of ionizing radiation. The simulation based on the Monte Carlo method and a Geant4 software code was applied to calculate the dependence of the number of beta-electrons entering a BSF-60 scintillation fiber on the activity of radiation sources based on 89Sr and 90Sr isotopes. An experimental study of the sensitivity of the developed fiber sensor and the measuring system to beta radiation of 89Sr and 90Sr isotopes showed a high degree of compliance with the proposed model. Keywords: Modeling, Computer simulation, Scintillation fiber, Dosimeter, Geant

Discovery of whitlockite in mantle xenoliths: Inferences for water- and halogen-poor fluids and trace element residence in the terrestrial upper mantle

Chemical analyses and Raman micro-spectroscopy have identified whitlockite (water- and halogen-free phosphate) in mantle xenoliths from Siberia. Whitlockite has not previously been reported from terrestrial mantle-derived rocks, but is the most common accessory phosphate in meteorites and igneous rocks from Mars and the Moon. The presence of the 'anhydrous' whitlockite, together with the breakdown of 'hydrous' accessory minerals (amphibole, phlogopite) in the same xenoliths, indicates that portions of the terrestrial upper mantle may be nearly as low in water and halogens as in inner parts of the smaller solar system bodies, regardless of enrichments of other highly mobile components (phosphorus, alkalis). Whitlockite may be an important host for some lithophile trace elements in those portions of the terrestrial mantle. It contains up to 3 times more rare earth elements than coexisting apatite but less Sr, Ba and U while Th abundances are similar. Thus, trace element abundances, patterns and ratios (e.g. Sr/Nd, Th/U) in whitlockite-bearing mantle rocks and coexisting fluids may be distinct from those for mantle rocks containing only apatite and/or other 'hydrous' minerals. Several generations of both whitlockite and apatite with different textural positions and abundances of Na, Mg, Sr and LREE were identified in some of the xenoliths. Furthermore, precipitation of the phosphates was accompanied by the formation of a distinct generation of clinopyroxene, which contains much less Zr (up to 10 times) but more LREE than clinopyroxenes formed in previous metasomatic episodes. (c) 2006 Elsevier B.V. All fights reserved

Study of high temperature and high density plasmoids in axially symmetrical magnetic fields : final report on the joint research project

[no abstract available