The neutral zinc sulfate solution obtained from hydrometallurgical process of Angouran zinc concentrate has cadmium, nickel and cobalt impurities, that must be purified before electrowinning. Therefore, cadmium and ni...The neutral zinc sulfate solution obtained from hydrometallurgical process of Angouran zinc concentrate has cadmium, nickel and cobalt impurities, that must be purified before electrowinning. Therefore, cadmium and nickel are usually cemented out by addition of zinc dust and remained nickel and cobalt cemented out at second stage with zinc powder and arsenic trioxide. In this research, a new approach is described for determination of effective parameters and optimization of zinc electrolyte hot purification process using statistical design of experiments. The Taguchi method based on orthogonal array design（OAD） has been used to arrange the experimental runs. The experimental conditions involved in the work are as follows： the temperature range of 70-90 ℃ for reaction temperature（T）, 30-90 min for reaction time（t）, 2-4 g/L for zinc powder mass concentration（M）, one to five series for zinc dust particle size distributions（S1-S5）, and 0.1-0.5 g/L（C） for arsenic trioxide mass concentration. Optimum conditions for hot purification obtained in this work are T4（85 ℃）, t4=75 min, M4=3.5 g/L, S4（Serie 4）, and C2=0.2 g/L.展开更多
Abstract In this paper, the authors characterize the inhomogeneous Triebel-Lizorkin spaces Fs,w p,q （Rn） with local weight w by using the Lusin-area functions for the full ranges of the indices, and then establish ...Abstract In this paper, the authors characterize the inhomogeneous Triebel-Lizorkin spaces Fs,w p,q （Rn） with local weight w by using the Lusin-area functions for the full ranges of the indices, and then establish their atomic decompositions for s ∈ R, p ∈ （0, 1] and q ∈ [p, ∞）. The novelty is that the weight w here satisfies the classical Muckenhoupt condition only on balls with their radii in （0, 1]. Finite atomic decompositions for smooth functions in Fs,w p,q（Rn） are also obtained, which further implies that a （sub）linear operator that maps smooth atoms of Fs,w p,q（Rn） uniformly into a bounded set of a （quasi-）Banach space is extended to a bounded operator on the whole Fs,w p,q（Rn） As an application, the baundedness of the local Riesz operator on the space Fs,w p,q（Rn） is obtained.展开更多
文摘The neutral zinc sulfate solution obtained from hydrometallurgical process of Angouran zinc concentrate has cadmium, nickel and cobalt impurities, that must be purified before electrowinning. Therefore, cadmium and nickel are usually cemented out by addition of zinc dust and remained nickel and cobalt cemented out at second stage with zinc powder and arsenic trioxide. In this research, a new approach is described for determination of effective parameters and optimization of zinc electrolyte hot purification process using statistical design of experiments. The Taguchi method based on orthogonal array design（OAD） has been used to arrange the experimental runs. The experimental conditions involved in the work are as follows： the temperature range of 70-90 ℃ for reaction temperature（T）, 30-90 min for reaction time（t）, 2-4 g/L for zinc powder mass concentration（M）, one to five series for zinc dust particle size distributions（S1-S5）, and 0.1-0.5 g/L（C） for arsenic trioxide mass concentration. Optimum conditions for hot purification obtained in this work are T4（85 ℃）, t4=75 min, M4=3.5 g/L, S4（Serie 4）, and C2=0.2 g/L.
基金supported by the National Natural Science Foundation of China(Nos.11101425,11171027)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20120003110003)
文摘Abstract In this paper, the authors characterize the inhomogeneous Triebel-Lizorkin spaces Fs,w p,q （Rn） with local weight w by using the Lusin-area functions for the full ranges of the indices, and then establish their atomic decompositions for s ∈ R, p ∈ （0, 1] and q ∈ [p, ∞）. The novelty is that the weight w here satisfies the classical Muckenhoupt condition only on balls with their radii in （0, 1]. Finite atomic decompositions for smooth functions in Fs,w p,q（Rn） are also obtained, which further implies that a （sub）linear operator that maps smooth atoms of Fs,w p,q（Rn） uniformly into a bounded set of a （quasi-）Banach space is extended to a bounded operator on the whole Fs,w p,q（Rn） As an application, the baundedness of the local Riesz operator on the space Fs,w p,q（Rn） is obtained.
