A PREDICTING MODEL OF THE LIMITING FLUX FOR THE CHARGED SOLUTE IN ULTRAFILTRATION PROCESS

In the process of ultrafiltration, the occurrence of the limiting flux iselucidated with the formation of a cake(gel) layer on the membrane surface. Before cake formation,the pressure drop on the concentration polarization layer, as well as the permeate flux, increaseswith the applied pressure. The pressure drop on the concentration polarization layer, however, willno longer change with the applied pressure after the formation of the cake layer. The limiting fluxwill be obtained if the hydrodynamic conditions in the filtration channel are not affected by thecake layer. A mathematics model for predicting the limiting flux for the charged solute inultrafiltration is developed. In this model, a repulsive electric force is taken into account inaddition to convection and diffusion when the solute is carrying the same charge as the membranematerial. A procedure to correlate the model with experimental ultrafiltration data is also present.The results show that a model in this paper is developed on a more realistic perception of theultrafiltration system and the predicting data agrees well with experimental data.

中国手机充电器标准化的潜在影响分析(英文)

The standardization of mobile phone charger is proceeding steadily in Europe. This paper makes a quantitative analysis on the potential impact of this move in China. The demands for mobile handset and phone charger in China after the introduction of standardization are predicted based on Bass diffusion model. The results indicate that the standardization would have little influence on mobile phone producers, but may charger makers face a fierce turbulence. Standardization would not only reduce the size of charger market, but also change the stable demand to a fluctuating pattern. Standardization of mobile phone charger can contribute to green economy greatly and provide the ICT industry a directive signal for green innovation in the future. Finally, suggestions for policy makers are provided based on the analysis.

Co-doping method used to improve the charge transport balance in solution processed OLEDs

In this paper, co-doping method is used to improve the current efficiency of solution-processed organic light-emitting diodes(OLEDs). By changing the ratio of two thermally activated delayed fluorescent(TADF) emitters, we studied the performance of device and its mechanism. A solution processed OLED with a structure of indium tin oxide(ITO, 150 nm)/PEDOT:PSS(30 nm)/CBP:4 Cz IPN-x%:4 Cz PN-y%(30 nm)/TPBi(40 nm)/Li F(1 nm)/Al(100 nm) was fabricated. The current efficiencies of 26.6 cd/A and 26.4 cd/A were achieved by the devices with dopant ratio of 6% 4 Cz IPN:2% 4 Cz PN and 2% 4 Cz IPN:6% 4 Cz PN in emitting material layer(EML), respectively. By investigating the tendency of current density change in devices with different doping ratio, we suggested that the enhancement of the current efficiency should be due to the charge transport balance improvement induced by assist dopant in EML.