To solve the problem of slow leaching speed of copper,surfactant was added into lixivium as leaching agent in the experiment.Based on physical chemistry and seepage flow mechanics,the leaching mechanics of surfactant ...To solve the problem of slow leaching speed of copper,surfactant was added into lixivium as leaching agent in the experiment.Based on physical chemistry and seepage flow mechanics,the leaching mechanics of surfactant was analyzed.The solution surface tension and surfactant adsorbing on the surface of ore have a significant impact on the surface wetting effect.With leaching rate for response,the study screened out three main factors by Plackett-Burman design method:the sulfuric acid concentration,surfactant concentration and temperature.Among these three factors,the surfactant concentration is the most important contributor to leaching rate.After obtaining the experiment center by the steepest ascent experiment,a continuous variable surface model was built by response surface methodology.By solving quadratic polynomial equation,optimal conditions for leaching were finally obtained as follows:the sulfuric acid concentration was 60 g/L,the surfactant concentration was 0.00914 mol/L,and the temperature was 45 °C.The leaching rate was 66.81% in the optimized leaching conditions,which was close to the predicted value,showing that regression result was good.展开更多
This paper addresses the composite nonlinear feedback（CNF） control for a class of singleinput single-output nonlinear systems with input saturation to track a time varying reference target with good transient perfor...This paper addresses the composite nonlinear feedback（CNF） control for a class of singleinput single-output nonlinear systems with input saturation to track a time varying reference target with good transient performance. The CNF control law consists of a tracking control law and a performance compensator. The tracking control law is designed to drive the output of the system to track the time varying reference target rapidly, while the performance compensator is used to reduce the overshoot caused by the tracking control law. The stability of the closed-loop system is established. The design procedure and the improvement of transient performance of the closed-loop system are illustrated with a numerical example and the controlled Van del Pol oscillator.展开更多
基金Projects (51374035,51304011) supported by the National Natural Science Foundation of ChinaProject (2012BAB08B02) supported by the National Key Technology R&D Program for the 12th Five-year Plan of China
文摘To solve the problem of slow leaching speed of copper,surfactant was added into lixivium as leaching agent in the experiment.Based on physical chemistry and seepage flow mechanics,the leaching mechanics of surfactant was analyzed.The solution surface tension and surfactant adsorbing on the surface of ore have a significant impact on the surface wetting effect.With leaching rate for response,the study screened out three main factors by Plackett-Burman design method:the sulfuric acid concentration,surfactant concentration and temperature.Among these three factors,the surfactant concentration is the most important contributor to leaching rate.After obtaining the experiment center by the steepest ascent experiment,a continuous variable surface model was built by response surface methodology.By solving quadratic polynomial equation,optimal conditions for leaching were finally obtained as follows:the sulfuric acid concentration was 60 g/L,the surfactant concentration was 0.00914 mol/L,and the temperature was 45 °C.The leaching rate was 66.81% in the optimized leaching conditions,which was close to the predicted value,showing that regression result was good.
基金supported by the National Nature Science Foundation of China under Grant Nos.61374035 and 61733017
文摘This paper addresses the composite nonlinear feedback（CNF） control for a class of singleinput single-output nonlinear systems with input saturation to track a time varying reference target with good transient performance. The CNF control law consists of a tracking control law and a performance compensator. The tracking control law is designed to drive the output of the system to track the time varying reference target rapidly, while the performance compensator is used to reduce the overshoot caused by the tracking control law. The stability of the closed-loop system is established. The design procedure and the improvement of transient performance of the closed-loop system are illustrated with a numerical example and the controlled Van del Pol oscillator.
