Brine,which is used to produce high-purity magnesia,was purified by XSC-700 to remove boron.Boron adsorption capacity of XSC-700 was investigated by varying the initial boron concentration,temperature,resin/brine rati...Brine,which is used to produce high-purity magnesia,was purified by XSC-700 to remove boron.Boron adsorption capacity of XSC-700 was investigated by varying the initial boron concentration,temperature,resin/brine ratio and stirring speed,while keeping the diameter at constant.The results show that boron adsorption capacity increases with increasing boron concentration,temperature,and decreases with increasing resin/brine ratio.And the stirring speed could slightly affect the boron adsorption capacity.The adsorption kinetics obeys the pseudo-second-order model.Equilibrium data were both examined by Freundlich and Langmuir isotherm equations and it can be well represented by the Freundlich isotherm equation.展开更多
The influence of sandstorms on train aerodynamic performance and safe running was studied in response to the frequent occurrence of sandstorm weather in north China.An Eulerian two-phase model in the computational flu...The influence of sandstorms on train aerodynamic performance and safe running was studied in response to the frequent occurrence of sandstorm weather in north China.An Eulerian two-phase model in the computational fluid dynamic (CFD) software FLUENT,validated with published data,was used to solve the gas-solid multiphase flow of a sandstorm around a train.The train aerodynamic performance under different sandstorm levels and no sand conditions was then simulated.Results showed that in sandstorm weather,the drag,lift,side forces and overturning moment increase by variable degrees.Based on a numerical analysis of aerodynamic characteristics,an equation of train stability was also derived using the theory of moment balance from the view of dynamics.A recommended speed limit of a train under different sandstorm levels was calculated based on the stability analysis.展开更多
基金Project(2008BAB35B04) supported by the National Key Technology R&D Program of China
文摘Brine,which is used to produce high-purity magnesia,was purified by XSC-700 to remove boron.Boron adsorption capacity of XSC-700 was investigated by varying the initial boron concentration,temperature,resin/brine ratio and stirring speed,while keeping the diameter at constant.The results show that boron adsorption capacity increases with increasing boron concentration,temperature,and decreases with increasing resin/brine ratio.And the stirring speed could slightly affect the boron adsorption capacity.The adsorption kinetics obeys the pseudo-second-order model.Equilibrium data were both examined by Freundlich and Langmuir isotherm equations and it can be well represented by the Freundlich isotherm equation.
基金Project(No.2009BAG12A01-C03) supported by the National Key Technology R&D Program of China
文摘The influence of sandstorms on train aerodynamic performance and safe running was studied in response to the frequent occurrence of sandstorm weather in north China.An Eulerian two-phase model in the computational fluid dynamic (CFD) software FLUENT,validated with published data,was used to solve the gas-solid multiphase flow of a sandstorm around a train.The train aerodynamic performance under different sandstorm levels and no sand conditions was then simulated.Results showed that in sandstorm weather,the drag,lift,side forces and overturning moment increase by variable degrees.Based on a numerical analysis of aerodynamic characteristics,an equation of train stability was also derived using the theory of moment balance from the view of dynamics.A recommended speed limit of a train under different sandstorm levels was calculated based on the stability analysis.
