The current blockade mechanism for λ -DNA translocation under electrical field is investigated through solid-state nanopores with different pore thicknesses. The conductance of a nanopore system mainly consists of t...The current blockade mechanism for λ -DNA translocation under electrical field is investigated through solid-state nanopores with different pore thicknesses. The conductance of a nanopore system mainly consists of the contribution of the pore and access region, and the latter becomes dominant when the nanopore thickness gradually decreases to atomic layer thickness. Based on the existing model of nanopore resistance, a simplified model which describes the relative current blockade during the X-DNA translocation through the nanopores is deduced to quantitatively present the relationship between nanopore thickness and relative current blockade. Results show that the relative current blockade is effectively increased by reducing the nanopore diameter but it decreases with the decreasing nanopore thickness. A two-stage schematic is proposed to increase the relative current blockade by setting a much smaller resistance region. Experimental results show a 21. 9% increase in the relative current blockade with the proposed schematic.展开更多
In the present study the membrane fouling in microfiltraiton used for cell harvesting in a deadend system has been investigated. Experimental results were analysed in terms of existing membrane filtration models and m...In the present study the membrane fouling in microfiltraiton used for cell harvesting in a deadend system has been investigated. Experimental results were analysed in terms of existing membrane filtration models and membrane resistances. The cake filtration model (CFM) and standard blocking model (SBM) have been considered in this study.Various membrane resistances were determined at different processing time, feed concentration and stirring speed. Resistances to permeation in this system include filter medium, pore blocking, adsorption, cake layer and concentration polarization.展开更多
基金The Natural Science Foundation of Jiangsu Province(No.BK20160935)the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(No.16KJB460015)
文摘The current blockade mechanism for λ -DNA translocation under electrical field is investigated through solid-state nanopores with different pore thicknesses. The conductance of a nanopore system mainly consists of the contribution of the pore and access region, and the latter becomes dominant when the nanopore thickness gradually decreases to atomic layer thickness. Based on the existing model of nanopore resistance, a simplified model which describes the relative current blockade during the X-DNA translocation through the nanopores is deduced to quantitatively present the relationship between nanopore thickness and relative current blockade. Results show that the relative current blockade is effectively increased by reducing the nanopore diameter but it decreases with the decreasing nanopore thickness. A two-stage schematic is proposed to increase the relative current blockade by setting a much smaller resistance region. Experimental results show a 21. 9% increase in the relative current blockade with the proposed schematic.
文摘In the present study the membrane fouling in microfiltraiton used for cell harvesting in a deadend system has been investigated. Experimental results were analysed in terms of existing membrane filtration models and membrane resistances. The cake filtration model (CFM) and standard blocking model (SBM) have been considered in this study.Various membrane resistances were determined at different processing time, feed concentration and stirring speed. Resistances to permeation in this system include filter medium, pore blocking, adsorption, cake layer and concentration polarization.
