The Possibility Assessment of Complex Processing of Technogenic Formations Containing Zinc Sulfide

The comprehensive methodology for the zinc extraction from sulfide compounds into the oxide form with possible further reduction to metal is presented in this study. It was demonstrated in laboratory conditions during sludge treatment with Zn and ZnO obtaining. The remaining silicate products. It is proposed to recycle this material into Portland cement clinker to ensure a waste-free process. Keywords: zinc sulfide, zinc oxide, sludge recycling, Portland cement clinker, waste-free recyclin

Metal Oxidation Control at the Stage of Refining Steel Smelting in Electric Arc Furnaces

The mathematical processing results of a number of EAF-135 melts electrical parameters are presented. The influence of the foamy slag formation, molten metal carburization and the harmful impurities oxidation on the change in electrical parameters is analyzed. The methodology for determining the metal oxidation from the electrical melt parameters is characterized. In the presented form, the technique is cumbersome for the rapid assessment of the oxidation process intensity and requires refinement. Keywords: Metal oxidation, electric parameters, electric arc furnac

Topological String Amplitudes, Complete Intersection Calabi-Yau Spaces and Threshold Corrections

We present the most complete list of mirror pairs of Calabi-Yau complete intersections in toric ambient varieties and develop the methods to solve the topological string and to calculate higher genus amplitudes on these compact Calabi-Yau spaces. These symplectic invariants are used to remove redundancies in examples. The construction of the B-model propagators leads to compatibility conditions, which constrain multi-parameter mirror maps. For K3 fibered Calabi-Yau spaces without reducible fibers we find closed formulas for all genus contributions in the fiber direction from the geometry of the fibration. If the heterotic dual to this geometry is known, the higher genus invariants can be identified with the degeneracies of BPS states contributing to gravitational threshold corrections and all genus checks on string duality in the perturbative regime are accomplished. We find, however, that the BPS degeneracies do not uniquely fix the non-perturbative completion of the heterotic string. For these geometries we can write the topological partition function in terms of the Donaldson-Thomas invariants and we perform a non-trivial check of S-duality in topological strings. We further investigate transitions via collapsing D5 del Pezzo surfaces and the occurrence of free Z2 quotients that lead to a new class of heterotic duals.Comment: 117 pages, 1 Postscript figur

Growth and characterization of CuxAg1-xInSe2 thin films by pulsed laser deposition

We report on structural and optical measurements made on thin films of the quaternary compounds CuxAg1-xInSe2(x = 0; 0.3; 0.5; 0.7; 1.0). The films were prepared by pulsed laser deposition (PLD) of prereacted material onto glass substrates. The substrate temperature was about 450-480 degrees C. The beam of a Nd:YAG laser was directed onto a rotating target. The resulting films were characterized by XRD, SEM, and EDAX, The films were single phase, polycrystalline and stoichiometric within 4 %. The refractive index n and the absorption coefficient alpha of CuxAg1-xInSe2 thin films were obtained by measuring the transmittance (T) and reflectance (R) in the photon energy range from 0.4 to 2.5 mu m. The optical properties were determined from rigorous expression for the transmission and reflection in an air/film/glass substrate/air multilayer system. The films had high optical absorption about 10(4) - 10(5) cm(-1) and the band gaps of 0.99 eV (CuInSe2) and 1.25 eV (AgInSe2). The energy gaps observed in laser-deposited CuxAg1-xInSe2 thin films near and above the fundamental absorption edge exhibit a nonlinear composition dependence