The circulation of Yellow Sea Cold Water Mass (YSCWM) in the Southern Yellow Sea is investigated using a diagnostic 2D MITgcm model. The resolution of the computational grid is 900 m in the horizontal and 2 m in the...The circulation of Yellow Sea Cold Water Mass (YSCWM) in the Southern Yellow Sea is investigated using a diagnostic 2D MITgcm model. The resolution of the computational grid is 900 m in the horizontal and 2 m in the vertical where an initial tem- perature distribution corresponding to a typical measured Yellow Sea Cold Water Mass was applied. The existence of YSCWM that causes fluid density difference, is shown to produce counter-rotating cyclonic horizontal eddies in the surface layer: the inner one is anti-cyclonic (clockwise) and relatively weaker (8-10cms-1) while the outer one is cyclonic (anti-clockwise) and much stronger (15-20cms-~). This result is consistent with the surface pattern observed by Pang et al. (2004), who has shown that a mesoscale anti-cyclonic eddy (clockwise) exists in the upper layer of central southern Yellow Sea, and a basin-scale cyclonic (anticlockwise) gyre lies outside of the anti-cyclonic eddy, based on the trajectories and drifting velocities of 23 drifters. Below the thermocline, there is an anti-cyclonic (clockwise) circulation. This complex current eddy system is considered to be capable of trapping suspended sediments and depositing them near the front between YSCWM and the coastal waters off the Subei coast, providing an explanation on the sediment depth and size distribution of mud patches in the Southern Yellow Sea. Moreover, sensitive test scenarios indicate that variations of bottom friction do not substantially change the main features of the circulation structure, but will reduce the bottom current velocity, increase the surface current velocity and weaken the upwelling around the frontal area.展开更多
Adsorption of diehtyl dithiophosphate on chalcopyrite has been studied using UV-visible spectroscopy at pH values of 4, 6, and 9. It was found that the adsorption of diethyl dithiophosphate decreased with the increasi...Adsorption of diehtyl dithiophosphate on chalcopyrite has been studied using UV-visible spectroscopy at pH values of 4, 6, and 9. It was found that the adsorption of diethyl dithiophosphate decreased with the increasing pH treatments. The inhibition of diethyl dithiophosphate adsorption was found prominent in higher pH as a result of metal hydroxide species formation onto chalcopyrite surface. First order kinetic has been proposed and represented the adsorption mechanism. Flotation test using Hallimond tube has also been conducted and the results were consistent with the proposed mechanism. Furthermore, the morphological changes of the treated chalcopyrite were observed using Atomic Force Microscopy (AFM) showing the propensity of growth of islands, the new surfaces as products of the reaction. The hydrophobicity was measured in the form of force of adhesion. The results resembled with the approached mechanism.展开更多
基金funded by the National Natural Science Foundation of China (NSFC) (Grant Nos. 41030856, 51479182 and 51425901)the Open Fund of State Key Laboratory of Hydraulics and Mountain River Engineering (Grant No. SKHL1428)The financial support through a PhD grant awarded to Chunyan Zhou by the University of Dundee, UK is gratefully acknowledged
文摘The circulation of Yellow Sea Cold Water Mass (YSCWM) in the Southern Yellow Sea is investigated using a diagnostic 2D MITgcm model. The resolution of the computational grid is 900 m in the horizontal and 2 m in the vertical where an initial tem- perature distribution corresponding to a typical measured Yellow Sea Cold Water Mass was applied. The existence of YSCWM that causes fluid density difference, is shown to produce counter-rotating cyclonic horizontal eddies in the surface layer: the inner one is anti-cyclonic (clockwise) and relatively weaker (8-10cms-1) while the outer one is cyclonic (anti-clockwise) and much stronger (15-20cms-~). This result is consistent with the surface pattern observed by Pang et al. (2004), who has shown that a mesoscale anti-cyclonic eddy (clockwise) exists in the upper layer of central southern Yellow Sea, and a basin-scale cyclonic (anticlockwise) gyre lies outside of the anti-cyclonic eddy, based on the trajectories and drifting velocities of 23 drifters. Below the thermocline, there is an anti-cyclonic (clockwise) circulation. This complex current eddy system is considered to be capable of trapping suspended sediments and depositing them near the front between YSCWM and the coastal waters off the Subei coast, providing an explanation on the sediment depth and size distribution of mud patches in the Southern Yellow Sea. Moreover, sensitive test scenarios indicate that variations of bottom friction do not substantially change the main features of the circulation structure, but will reduce the bottom current velocity, increase the surface current velocity and weaken the upwelling around the frontal area.
文摘Adsorption of diehtyl dithiophosphate on chalcopyrite has been studied using UV-visible spectroscopy at pH values of 4, 6, and 9. It was found that the adsorption of diethyl dithiophosphate decreased with the increasing pH treatments. The inhibition of diethyl dithiophosphate adsorption was found prominent in higher pH as a result of metal hydroxide species formation onto chalcopyrite surface. First order kinetic has been proposed and represented the adsorption mechanism. Flotation test using Hallimond tube has also been conducted and the results were consistent with the proposed mechanism. Furthermore, the morphological changes of the treated chalcopyrite were observed using Atomic Force Microscopy (AFM) showing the propensity of growth of islands, the new surfaces as products of the reaction. The hydrophobicity was measured in the form of force of adhesion. The results resembled with the approached mechanism.