Analysis of the Specific Features of Wear of the Working Rolls of the Finishing Group of Stands Under Conditions of the 1950 Mill at the Casting-Rolling Complex of the “VMZ” JSC

Metallurgist - We present the analysis of the mechanism of in-service wear of the working rolls of wide-band rolling mills on an example of a 1950 mill from the casting-rolling complex of the...     

Investigation of the Service Properties of the Electroslag Cast Metal

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Can we improve the prevention of tuberculosis? Analysis of the application of chemoprophylaxis

Social ethics of affirmative postmodernists are discussed in relation to recent German health care legislation. It could be shown that: 1. the health care legislation 1989 and 1993 only partially fulfills the postmodern call for "cultivation of individual responsibility", 2. both laws largely fail to enforce the principle of subsidiarity, and 3. postmodernist thinking is weak on the question of global strategies but strong In the area of individualism and subjectivity. We conclude that postmodern social ethics are useful to compensate areas largely neglected by recent German health care legislation, rather than that the legislation is an example of postmodern social ethics.     

Improvement of the technique of calculating the energy–force parameters of pinch-pass mills for increasing the efficiency of producing cold-rolled strips

New propositions are introduced into the technique of energy-force calculation of pinch-pass mills in order to determine the energy–force and technological parameters of skin rolling of cold-rolled steel strips at the minimum errors. The application of these propositions decreases the errors of calculating the forces and torques in a working stand by a factor of 3–5 as compared to the calculation according to the well-known technique, saves the electric power in the existing mills, and demonstrates the possibility of decreasing the dimensions of working stands and the power of the rolling mill engine.     

Increasing the Efficiency of the Recycling of Propylene—Polyethylene Raw Materials

The problem of the recycling of plastic wastes is discussed. The polypropylene needs of the modern Russian market are analyzed. The necessity of recycling of plastic wastes is revealed, and its advantages over reclamation are substantiated. The problems of a real enterprise regarding the recycling of polypropylene—polyethylene raw materials for increasing the properties of the end product and optimizing its production are considered, and methods for their solution are proposed.     

Is the release of noradrenaline necessary for self-stimulation of the brain?

A totally voluntary plasmapheresis program recruits 900 individual donors per year at a cancer institute, where 500 to 900 units of platelets are transfused each month. Staff and donors use a film and brochures to recruit donors from the local community. Television and radio spots, with donor recognition pins, certificates, receptions, and picnics are utilized. Donor motivation was studied by use of: 1) California Psychological Inventory--measures a variety of "normal" personality traits; 2) Study of values--measures theoretical, economic, aesthetic, social, political, religious values; 3) Internal-External Control Scale--measures degree to which a person blames self vs. external events for what happens to him; 4) Faith in People Scale--measures individual's confidence in his fellow man; 5) Anomia Scale--measure of feelings of self-to-others alienation; 6) Mach IV Scale--measure of persons tendency to manipulate others; and 7) Biographical Data Form. Results are presented for 25 male donor subjects studied, as they compare with normative data for the scales used. Donors appeared to have the same traits as do the general population, but appeared lower in Machiavellianism than non-plasmapheresis donors. Prospective study plans include additional subjects to provide appropriate control groups.     

Physicochemical laws of the atmospheric sulfuric acid leaching of the copper—nickel concentrates from the beneficiation of disseminated ores

A physicochemical substantiation is performed for the organization of a combined flotation hydrometallurgical technology for the processing of the copper??nickel concentrates from the beneficiation of disseminated ores. This technology is used instead of the traditional pyrometallurgical technology providing the production of a sulfide concentrate with a total nickel, copper, and cobalt content of 14.64% for the through extraction of (wt %) 92.2 Ni, 74.0 Cu, 95.3 Co, 91.9 Pt, 95.9 Pd, and 96 Rh to the concentrate.     

Impact of the Travelling Magnetic Field on the Metallic Impurities During the Crystallization of Photovoltaic Silicon

Silicon is the most extensively studied semiconductor mainly owing to its wide applicability in the photovoltaic solar cell industry.However the qualily of Si photovoltaic cells depends on the purity of the material and on the grain structure of the ingot from which the wafers are cutting.The electrical performance of such materials,i.e.mainly their minority carrier lifetime,is closely related to metal impurities present in the feedstock or introduced during crystal growth.These impurities strongly interact with existing crystal defects to form complexes,accumulate at dislocations or grain boundaries in different forms,or even form silieide precipitates,which simultaneously contain several metal impurities.In such a context,it is necessary to control the segregation of impurities especially metallic in the grown ingot in order to optimize the cell properties as a function of the raw material purity.A new Bridgman set-up is developed in order to study the crystallization of photovoltaic Si under independently controlled solidification parameters growth rate,thermal gradient,purity and convection.Convection,either natural or forced,plays a very important role during the crystallization.Its intensity and flow pattern affect heat and mass transfer and,consequently,macrostructure and segregation in a solidified ingot.Here the convection can be controlled by a travelling magnetic field in order to homogenize or segregate the rejected impurities such as metallic elements.The effects of the magnetic field intensity and frequency on the segregation and crystalline structure will be presented.     

Improving the Corrosion Resistance of the Nickel–Tungsten Alloy by Optimization of the Electroplating Conditions

Nickel–tungsten (Ni–W) alloy coating was electrodeposited on the copper substrate by direct current voltammetry. The optimization of a free-ammonium bath for electrodeposition of Ni–W alloy coating was investigated. Experiments were focused on elucidating the effect of W concentration and operating conditions on the corrosion performance of the obtained Ni–W alloy coating. The corrosion behavior of the coatings was investigated by potentiodynamic polarization (Tafel) test. Experimental data such as corrosion current density, corrosion rate and polarization resistance indicated that the operating conditions used during the electroplating had significant effects on the corrosion parameters of the Ni–W alloy coating. The results showed that the highest corrosion resistance was obtained for the coating with 56.7 wt% tungsten (Ni/W ratio of 1:2.5) which was prepared at the current density of 3.8 A dm^?2. The increase in the corrosion resistance at the optimum current density was attributed to the lower interferences of the hydrogen evolution reaction. Energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) techniques were used to characterize the electrodeposited Ni–W alloy with the best anti-corrosion parameters.

     

Structure and thermal properties of the matte of the autogenous smelting of copper–zinc concentrates

The phase composition and the structure of the solidified mattes of the autogenous smelting of copper–zinc concentrates containing 49.8 and 61.0% Cu in Vanyukov’s furnace are studied. The forms of the main elements (Cu, Ni, Fe, S, O) and the accompanying impurities (Zn, Pb, As, Sb, Co, Sn, Au, Ag) in the rich matte are determined. The phase-transformation temperatures in cooling of the mattes in an inert or oxidizing gas atmosphere are found.     

Report of the… .

Asummary of a report containing "information about subdoctoral training programs,… questions the committee deemed relevant and important,… and appropriate recommendations." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Theoretical and experimental investigation of the process of plastic deformation of sintered composite materials IV. Technological basis for controlling the state of the elements of the“hard” phase during deformation

Conclusions A relationship has been established between the level of compressive stress necessary for the commencement of simultaneous deformation of the dissimilar phases of a composite material on the one hand and, on the other, the magnitude of the jump in strength properties at the interfaces between these phases and the geometry of shape of thehard inclusions (parameter l/d). The feasibility is shown of predicting the behavior of thehard inclusions during the deformation of a composite material by analysis of the stressed state attained under any given conditions of plastic working. The basic principles have been determined of devising a technological process for the production of composite materials of fibrous structure from sintered blanks.Translated from Poroshkovaya Metallurgiya, No. 11(299), pp. 38–42, November, 1987.