The higher-order attraction of pullback attractors for non-autonomous parabolic equations involving Grushin operators is considered. Firstly, the maximum principle is studied.Next, the higher-order integrability of th...The higher-order attraction of pullback attractors for non-autonomous parabolic equations involving Grushin operators is considered. Firstly, the maximum principle is studied.Next, the higher-order integrability of the difference of weak solutions is established. Finally,the higher-order attraction is proved.展开更多
Leaching selectivity during metal recovery from complex electronic waste using a hydrochemical process is always one of the generic issues. It was recently improved by using ammonia-based leaching process, specificall...Leaching selectivity during metal recovery from complex electronic waste using a hydrochemical process is always one of the generic issues. It was recently improved by using ammonia-based leaching process, specifically for electronic waste enriched with copper. This research proposes electrodeposition as the subsequent approach to effectively recover copper from the solutions after selective leaching of the electronic waste and focuses on recognising the electrochemical features of copper recovery. The electrochemical reactions were investigated by considering the effects of copper concentration, scan rate and ammonium salts. The diffusion coefficient, charge transfer coefficient and heterogeneous reaction constant of the electrodeposition process were evaluated in accordance with different solution conditions. The results have shown that electrochemical recovery of copper from ammonia- based solution under the conditions of selective electronic waste treatment is charge transfer controlled and provide bases to correlate the kinetic parameters with further optimisation of the selective recovery of metals from electronic waste.展开更多
基金Supported by Tian Yuan Fund of Mathematics(Grant No.11326100)the Natural Science Fundation of Gansu Province(Grant No.145RJZA033)
文摘The higher-order attraction of pullback attractors for non-autonomous parabolic equations involving Grushin operators is considered. Firstly, the maximum principle is studied.Next, the higher-order integrability of the difference of weak solutions is established. Finally,the higher-order attraction is proved.
文摘Leaching selectivity during metal recovery from complex electronic waste using a hydrochemical process is always one of the generic issues. It was recently improved by using ammonia-based leaching process, specifically for electronic waste enriched with copper. This research proposes electrodeposition as the subsequent approach to effectively recover copper from the solutions after selective leaching of the electronic waste and focuses on recognising the electrochemical features of copper recovery. The electrochemical reactions were investigated by considering the effects of copper concentration, scan rate and ammonium salts. The diffusion coefficient, charge transfer coefficient and heterogeneous reaction constant of the electrodeposition process were evaluated in accordance with different solution conditions. The results have shown that electrochemical recovery of copper from ammonia- based solution under the conditions of selective electronic waste treatment is charge transfer controlled and provide bases to correlate the kinetic parameters with further optimisation of the selective recovery of metals from electronic waste.
