In order to effectively separate galena and jamesonite and improve the recovery during the mixing flotation, the interaction mechanisms between the minerals and the collector of diethyl dithiocarbamate （DDTC） were i...In order to effectively separate galena and jamesonite and improve the recovery during the mixing flotation, the interaction mechanisms between the minerals and the collector of diethyl dithiocarbamate （DDTC） were investigated. Single mineral flotation test was organized to research the effect of pulp pH value on the flotation behavior of galena and jamesonite. Electrochemistry property of the interaction of these two minerals with DDTC was investigated by cyclic voltammetry and Tafel tests. Flotation test shows that the recovery of jamesonite in high alkaline pulp is strongly depressed by lime （Ca（OH）2）. The cyclic voltammetry and Tafel tests results show that the interaction between galena and DDTC is an electrochemical process. High pH value has little influence on the interaction between galena and DDTC, while it has great effect on jamesonite due to self-oxidation and specific adsorption of OH^- and CaOH^＋ on jamesonite surface. Non-electroactive hydroxyl compound and low-electroconductive calcium compounds cover the surface of jamesonite, which impedes electron transfer and DDTC adsorption, thus leads to very low floatability of jamesonite.展开更多
A new reliability-based multidisciplinary design optimization （RBMDO） framework is proposed by combining the single-loop-based reliability analysis （SLBRA） method with multidisciplinary feasible （MDF） method. Th...A new reliability-based multidisciplinary design optimization （RBMDO） framework is proposed by combining the single-loop-based reliability analysis （SLBRA） method with multidisciplinary feasible （MDF） method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design.展开更多
Growth and crystallization of titanium anodized films were studied by performing the anodization of the sputter-deposited titanium samples under cyclic voltammetry （CV） mode at very low potentials. The surface featu...Growth and crystallization of titanium anodized films were studied by performing the anodization of the sputter-deposited titanium samples under cyclic voltammetry （CV） mode at very low potentials. The surface features, crystalline behaviors and chemical compositions of the formed anodic oxide layers were detected by AFM, SE and XPS. It was found that the structure of the titanium anodized films is crystalline, even though the maximum oxidation potential （（Pmax） is very low （as low as 1000 mY）. Both enlarging the applied voltage and reducing the potential scanning rate are beneficial for the growth and crystallization of titanium oxide films. It was thought that the internal compressive stress, other than the local joule heating accepted for many researchers, is the main force of stimulating the crystallization of anodic titanium oxide films at very low potentials.展开更多
Electrochemical behavior of layered LiNi0.5Mn0.5O2 in LiNO3 aqueous solution and its cyclic fading mechanism in electrolytes with different pH values were investigated. CV results show that LiNi0.5Mn0.5O2 has good ele...Electrochemical behavior of layered LiNi0.5Mn0.5O2 in LiNO3 aqueous solution and its cyclic fading mechanism in electrolytes with different pH values were investigated. CV results show that LiNi0.5Mn0.5O2 has good electrochemical reversible behaviors in 5 mol/L LiNO3 solution. Meanwhile, the electrode in 5 mol/L LiNO3 with pH value of 12 demonstrates the best electrochemical stability. Based on the electrochemical impedance spectroscopy （EIS）, X-ray diffraction （XRD） and scanning electron microscopy （SEM） results, it is proposed that suppressed charge-transfer resistance is the major reason, which is probably ascribed to the more stable electrode surface and less structure change.展开更多
Aim To investigate the electrochemical behaviors of Mitomycin C （MC） and its interaction with calf thymus DNA （ctDNA）. Methods The cyclic vohammetry （CV） was carried out at a paraffined graphite electrode. Resul...Aim To investigate the electrochemical behaviors of Mitomycin C （MC） and its interaction with calf thymus DNA （ctDNA）. Methods The cyclic vohammetry （CV） was carried out at a paraffined graphite electrode. Results MC showed a well-defined oxidation-reduction peak. As a result of reaction with ctDNA, the peak current of MC decreased apparently. According to corresponding electrochemical equations, the diffusion coefficient of both free and MC-DNA complex have been determined, and the heterogeneous rate constants were also obtained simultaneously. Conclusion The solid paraffined graphite electrode could be used to estimate parameters of the interaction between DNA and MC, and provide the convenient and sensitive analysis.展开更多
基金Projects(5110417951374247)supported by the National Natural Science Foundation of China
文摘In order to effectively separate galena and jamesonite and improve the recovery during the mixing flotation, the interaction mechanisms between the minerals and the collector of diethyl dithiocarbamate （DDTC） were investigated. Single mineral flotation test was organized to research the effect of pulp pH value on the flotation behavior of galena and jamesonite. Electrochemistry property of the interaction of these two minerals with DDTC was investigated by cyclic voltammetry and Tafel tests. Flotation test shows that the recovery of jamesonite in high alkaline pulp is strongly depressed by lime （Ca（OH）2）. The cyclic voltammetry and Tafel tests results show that the interaction between galena and DDTC is an electrochemical process. High pH value has little influence on the interaction between galena and DDTC, while it has great effect on jamesonite due to self-oxidation and specific adsorption of OH^- and CaOH^＋ on jamesonite surface. Non-electroactive hydroxyl compound and low-electroconductive calcium compounds cover the surface of jamesonite, which impedes electron transfer and DDTC adsorption, thus leads to very low floatability of jamesonite.
基金Supported by the National High Technology Research and Development Program of China("863" Program) (2009AA04Z418, 2007AA04Z404)the National "111" Project(B07050)~~
文摘A new reliability-based multidisciplinary design optimization （RBMDO） framework is proposed by combining the single-loop-based reliability analysis （SLBRA） method with multidisciplinary feasible （MDF） method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design.
基金Project(20976058)supported by the National Natural Science Foundation of China
文摘Growth and crystallization of titanium anodized films were studied by performing the anodization of the sputter-deposited titanium samples under cyclic voltammetry （CV） mode at very low potentials. The surface features, crystalline behaviors and chemical compositions of the formed anodic oxide layers were detected by AFM, SE and XPS. It was found that the structure of the titanium anodized films is crystalline, even though the maximum oxidation potential （（Pmax） is very low （as low as 1000 mY）. Both enlarging the applied voltage and reducing the potential scanning rate are beneficial for the growth and crystallization of titanium oxide films. It was thought that the internal compressive stress, other than the local joule heating accepted for many researchers, is the main force of stimulating the crystallization of anodic titanium oxide films at very low potentials.
基金Project(21301193)supported by the National Nature Science Foundation of ChinaProject(2013M530356)supported by the China Postdoctoral Science Foundation Funded+1 种基金Project(CUSZC201303)supported by the Scientific Research Foundation of Central South Universitythe Open-End Found for Valuable and Precision Instruments of Central South University
文摘Electrochemical behavior of layered LiNi0.5Mn0.5O2 in LiNO3 aqueous solution and its cyclic fading mechanism in electrolytes with different pH values were investigated. CV results show that LiNi0.5Mn0.5O2 has good electrochemical reversible behaviors in 5 mol/L LiNO3 solution. Meanwhile, the electrode in 5 mol/L LiNO3 with pH value of 12 demonstrates the best electrochemical stability. Based on the electrochemical impedance spectroscopy （EIS）, X-ray diffraction （XRD） and scanning electron microscopy （SEM） results, it is proposed that suppressed charge-transfer resistance is the major reason, which is probably ascribed to the more stable electrode surface and less structure change.
文摘Aim To investigate the electrochemical behaviors of Mitomycin C （MC） and its interaction with calf thymus DNA （ctDNA）. Methods The cyclic vohammetry （CV） was carried out at a paraffined graphite electrode. Results MC showed a well-defined oxidation-reduction peak. As a result of reaction with ctDNA, the peak current of MC decreased apparently. According to corresponding electrochemical equations, the diffusion coefficient of both free and MC-DNA complex have been determined, and the heterogeneous rate constants were also obtained simultaneously. Conclusion The solid paraffined graphite electrode could be used to estimate parameters of the interaction between DNA and MC, and provide the convenient and sensitive analysis.
