Recovery of zinc from zinc oxide dust containing multiple metal elements by carbothermal reduction

A carbothermal reduction process simulating EAF process is used to handle the zinc oxide dust, and the zinc in the dust can be extracted and recovered efficiently. The crude zinc and lead-tin alloy were obtained finally. The effects of temperature, holding time, and reductant dosage on zincvolatilization rate were investigated, and the ?Pelletizing -Calcination-Carbothermic reduction? experiment was conducted. The resultsfound the optimal reduction condition was as follows: the temperature of 1300?C, reductant dosage of 14.04% and holding time of 120 min. After the calcination at 900?C for 120 min, the removal rates of fluorine, chlorine and sulfur in the dust were 98.18%, 96.38% and 28.58% respectively, and the volatilization rate of zinc was 99.83% in reduction process. The zinc content of the crude zinc was 68.48%.

Sidelobe Reduction in a Planar Array using Genetic Algorithm under Backlobe Reduction Condition

The peak sidelobe level (PSL) minimizing amplitude weights for planar array, with 3D beamforming under the backlobe level reduction (BLL) condition is proposed. Binary genetic algorithm (BGA) is performed on the amplitude weights to achieve low PSL. BLL reduction condition for the inter-element distance between the antenna elements is applied to achieve reduced BLL. Earlier studies only focus on minimizing sidelobe level of planar array. BLL reduction condition has not yet been applied for planar array case. Hence a different way of achieving the amplitude weights to reduce PSL with 3D beamforming using BGA, under the BLL reduction condition is proposed in this paper. Obtained PSL and BLL for planar array by applying optimized weights under BLL condition is -20.89 dB and -2.37 dB respectively. PSL is reduced by 8.84 dB compared to uniform planar array. BLL is reduced by 2.37 dB compared to planar array discussed in existing research work.

FROM STENIUS’ CONSISTENCY PROOF TO SCHÜTTE’S CUT ELIMINATION FOR ω-ARITHMETIC

The book Das Interpretationsproblem der Formalisierten Zahlentheorie und ihre Formale Widerspruchsfreiheit by Erik Stenius published in 1952 contains a consistency proof for infinite ω-arithmetic based on a semantical interpretation. Despite the proof’s reference to semantics the truth definition is in fact equivalent to a syntactical derivability or reduction condition. Based on this reduction condition Stenius proves that the complexity of formulas in a derivation can be limited by the complexity of the conclusion. This independent result can also be proved by cut elimination for ω-arithmetic which was done by Schütte in 1951.In this paper we interpret the syntactic reduction in Stenius’ work as a method for cut elimination based on invertibility of the logical rules. Through this interpretation the constructivity of Stenius’ proof becomes apparent. This improvement was explicitly requested from Stenius by Paul Bernays in private correspondence (In a letter from Bernays begun on the 19th of September 1952 (Stenius & Bernays, 1951–75)). Bernays, who took a deep interest in Stenius’ manuscript, applied the described method in a proof Herbrand’s theorem. In this paper we prove Herbrand’s theorem, as an application of Stenius’ work, based on lecture notes of Bernays (Bernays, 1961). The main result completely resolves Bernays’ suggestions for improvement by eliminating references to Stenius’ semantics and by showing the constructive nature of the proof. A comparison with Schütte’s cut elimination proof shows how Stenius’ simplification of the reduction of universal cut formulas, which in Schütte’s proof requires duplication and repositioning of the cuts, shifts the problematic case of reduction to implications.

Determinant Representation of Binary Darboux Transformation for the AKNS Equation

In this paper, the determinant representation of the n-fold binary Darboux transformation, which is a 2×2 matrix, for the Ablowitz–Kaup–Newell–Segur equation is constructed. In this 2×2 matrix, each element is expressed by (2n+1)-order determinants. When the reduction condition r=–q̅ is considered, we obtain one of binary Darboux transformations for the nonlinear Schrödinger (NLS) equation. As its applications, several solutions are constructed for the NLS equation. Especially, a new form of two-soliton is given explicitly.

An optimized mild reduction route towards excellent cobalt–graphene catalysts for water oxidation

A highly active and stable cobalt–graphene electrocatalyst for oxygen evolution reaction (OER) is produced by optimizing the reduction condition of graphene oxide in terms of temperature and time.