The escalation of zeta potential by the influence of wall slip for the electrokinetically modulated flow through a microchannel motivates to consider the impact of hydrodynamic slippage upon the zeta or surface potent...The escalation of zeta potential by the influence of wall slip for the electrokinetically modulated flow through a microchannel motivates to consider the impact of hydrodynamic slippage upon the zeta or surface potential.The reported study undergoes an analytical exploration of the pulsatile electroosmosis and shear-actuated flow characteristics of a fluid with a Newtonian model through a microchannel with parallel plates by invoking the reliance of a zeta or surface potential on slippage.The linearized Poisson-Boltzmann and momentum equations are solved analytically to obtain the explicit expression of the electrical potential induced in the electrical double layer(EDL),the flow velocity field,and the volumetric flow rate for an extensive span of parameters.The velocity field proximal to the microchannel wall is observed to enhance by an apparent zeta potential,and is further escalated for a thinner EDL and an oscillating electric field with a higher amplitude.However,near the core region of the microchannel,the flow velocity becomes invariant with the EDL thickness.The result shows that the lower wall velocity contributes to the flow velocity along with the electroosmotic body force and the impact of the velocity of the wall underneath diminishes proximal to the upper wall.Moreover,the volumetric flow rate increases when the thickness of the EDL decreases,owing to the influence of the wall slip.However,for thinner EDLs and medium and higher oscillating Reynolds numbers,the volumetric flow rate varies non-monotonously,correlative to the slip-free and slip cases.展开更多
Rare earth elements are indispensable raw materials for advanced aero-engines, special optical materials, and high-performance electronic products. With the development of the social economy, the global demand for rar...Rare earth elements are indispensable raw materials for advanced aero-engines, special optical materials, and high-performance electronic products. With the development of the social economy, the global demand for rare earth resources is increasing, and rare earths have become a key metal for the development of new industries and frontier technologies that are highly valued both at home and abroad. Ion-adsorbed rare earth ores are an important source of rare earths, so the efficient green leaching of ion-adsorbed rare earths is important. Researchers found that the selection of an efficient green leaching agent for ion-adsorbed rare earths is based on the zeta potential of tailing clay minerals in addition to leaching efficiency, and both zeta potential and leaching ion concentration are related to mineral acidity and alkalinity, and the pH of tailing water suspension is a direct indicator of environmental water quality requirements. Therefore, the efficiency of the leaching process is closely integrated with the environmental evaluation, and the characteristics and correlation of the changes in zeta potential, pH, conductivity and pollutant concentration of the pulp of clay mineral content during the leaching process of ore leaching and tailings aqueous electrolyte solution leaching are studied by evaluating the leaching system, and a set of correlation leaching efficiency and environmental impact evaluation method is established based on the results of the above analysis, which is of scientific development of ion adsorption rare earth resources. It has important theoretical significance and practical application value.展开更多
对不同品种大豆分离蛋白(soybean protein isolate,SPI)的表面疏水性、氨基酸组成及溶液的Zeta电位和粒径分布进行分析,探讨蛋白质溶液Zeta电位和粒径分布与表面疏水性的关系。不同品种SPI的表面疏水性由大到小的变化趋势为:东农46>...对不同品种大豆分离蛋白(soybean protein isolate,SPI)的表面疏水性、氨基酸组成及溶液的Zeta电位和粒径分布进行分析,探讨蛋白质溶液Zeta电位和粒径分布与表面疏水性的关系。不同品种SPI的表面疏水性由大到小的变化趋势为:东农46>皖豆24>黑农46>五星4>中黄13>冀NF58,品种差异对SPI的Zeta电位及粒径分布具有显著影响。相关性分析表明,SPI表面疏水性与氨基酸组成无显著相关性,表面疏水性与Zeta电位绝对值呈显著的正相关,与粒径大小呈显著的负相关。当蛋白溶液Zeta电位绝对值较大时,蛋白表面更多同性电荷间的排斥作用会减少蛋白分子的相互聚集,使蛋白溶液趋于稳定,同时降低蛋白质粒径大小。此时,蛋白质疏水基团的内卷程度降低,并更多暴露在分子表面,导致蛋白质表面疏水性增加。展开更多
文摘The escalation of zeta potential by the influence of wall slip for the electrokinetically modulated flow through a microchannel motivates to consider the impact of hydrodynamic slippage upon the zeta or surface potential.The reported study undergoes an analytical exploration of the pulsatile electroosmosis and shear-actuated flow characteristics of a fluid with a Newtonian model through a microchannel with parallel plates by invoking the reliance of a zeta or surface potential on slippage.The linearized Poisson-Boltzmann and momentum equations are solved analytically to obtain the explicit expression of the electrical potential induced in the electrical double layer(EDL),the flow velocity field,and the volumetric flow rate for an extensive span of parameters.The velocity field proximal to the microchannel wall is observed to enhance by an apparent zeta potential,and is further escalated for a thinner EDL and an oscillating electric field with a higher amplitude.However,near the core region of the microchannel,the flow velocity becomes invariant with the EDL thickness.The result shows that the lower wall velocity contributes to the flow velocity along with the electroosmotic body force and the impact of the velocity of the wall underneath diminishes proximal to the upper wall.Moreover,the volumetric flow rate increases when the thickness of the EDL decreases,owing to the influence of the wall slip.However,for thinner EDLs and medium and higher oscillating Reynolds numbers,the volumetric flow rate varies non-monotonously,correlative to the slip-free and slip cases.
文摘Rare earth elements are indispensable raw materials for advanced aero-engines, special optical materials, and high-performance electronic products. With the development of the social economy, the global demand for rare earth resources is increasing, and rare earths have become a key metal for the development of new industries and frontier technologies that are highly valued both at home and abroad. Ion-adsorbed rare earth ores are an important source of rare earths, so the efficient green leaching of ion-adsorbed rare earths is important. Researchers found that the selection of an efficient green leaching agent for ion-adsorbed rare earths is based on the zeta potential of tailing clay minerals in addition to leaching efficiency, and both zeta potential and leaching ion concentration are related to mineral acidity and alkalinity, and the pH of tailing water suspension is a direct indicator of environmental water quality requirements. Therefore, the efficiency of the leaching process is closely integrated with the environmental evaluation, and the characteristics and correlation of the changes in zeta potential, pH, conductivity and pollutant concentration of the pulp of clay mineral content during the leaching process of ore leaching and tailings aqueous electrolyte solution leaching are studied by evaluating the leaching system, and a set of correlation leaching efficiency and environmental impact evaluation method is established based on the results of the above analysis, which is of scientific development of ion adsorption rare earth resources. It has important theoretical significance and practical application value.
文摘对不同品种大豆分离蛋白(soybean protein isolate,SPI)的表面疏水性、氨基酸组成及溶液的Zeta电位和粒径分布进行分析,探讨蛋白质溶液Zeta电位和粒径分布与表面疏水性的关系。不同品种SPI的表面疏水性由大到小的变化趋势为:东农46>皖豆24>黑农46>五星4>中黄13>冀NF58,品种差异对SPI的Zeta电位及粒径分布具有显著影响。相关性分析表明,SPI表面疏水性与氨基酸组成无显著相关性,表面疏水性与Zeta电位绝对值呈显著的正相关,与粒径大小呈显著的负相关。当蛋白溶液Zeta电位绝对值较大时,蛋白表面更多同性电荷间的排斥作用会减少蛋白分子的相互聚集,使蛋白溶液趋于稳定,同时降低蛋白质粒径大小。此时,蛋白质疏水基团的内卷程度降低,并更多暴露在分子表面,导致蛋白质表面疏水性增加。
