Isotactic polypropylene(iPP) hollow fiber microporous membranes were prepared via thermally induced phase separation(TIPS)method.The mixture of di-n-butyl phthalate(DBP)and dioctyl phthalate(DOP)was used as diluent.Th...Isotactic polypropylene(iPP) hollow fiber microporous membranes were prepared via thermally induced phase separation(TIPS)method.The mixture of di-n-butyl phthalate(DBP)and dioctyl phthalate(DOP)was used as diluent.The effects of α(DBP mass fraction in mixed diluent)and β(iPP mass fraction in polymer solution)on pore size distribution of the membrane were investigated by N2-liquid displacement measurement.The connectivity of the membrane was evaluated with membrane tortuosity.It is noted that resulting membrane is apt to possess a narrow pore size distribution.For same β,the mean pore size and connectivity of resulting membrane decrease with increasing α.For α=0.20,with increasing β,mean pore size of resulting membrane increases with subsequent decreasing,while resulting membrane connectivity increases slightly.For α=0.35 or α=0.50,the mean pore size and connectivity of resulting membrane decrease with increasing β.It is indicated that the change of connectivity is attributed to the difference of the membrane topology.It is shown that membrane pore size and connectivity can be controlled effectively by choosing proper α and β.展开更多
利用英国Legion Studio 2006步行人流模拟软件为平台,以北京北苑交通枢纽方案设计为例,对北苑枢纽内部行人交通组织与空间换乘情况进行仿真模拟研究.仿真输出结果分别验证了现况天通苑北站及北苑枢纽设计方案中各项行人交通设施的不足...利用英国Legion Studio 2006步行人流模拟软件为平台,以北京北苑交通枢纽方案设计为例,对北苑枢纽内部行人交通组织与空间换乘情况进行仿真模拟研究.仿真输出结果分别验证了现况天通苑北站及北苑枢纽设计方案中各项行人交通设施的不足点与合理之处,通过仿真模拟发现设计弊端,从而能够预先解决问题.随着计算机仿真技术在国际交通工程界的推广,微观人流仿真作为一种有效的研究方法,将更好地为综合交通枢纽规划与设计相关工作提供有力的技术支持与分析依据.展开更多
文摘Isotactic polypropylene(iPP) hollow fiber microporous membranes were prepared via thermally induced phase separation(TIPS)method.The mixture of di-n-butyl phthalate(DBP)and dioctyl phthalate(DOP)was used as diluent.The effects of α(DBP mass fraction in mixed diluent)and β(iPP mass fraction in polymer solution)on pore size distribution of the membrane were investigated by N2-liquid displacement measurement.The connectivity of the membrane was evaluated with membrane tortuosity.It is noted that resulting membrane is apt to possess a narrow pore size distribution.For same β,the mean pore size and connectivity of resulting membrane decrease with increasing α.For α=0.20,with increasing β,mean pore size of resulting membrane increases with subsequent decreasing,while resulting membrane connectivity increases slightly.For α=0.35 or α=0.50,the mean pore size and connectivity of resulting membrane decrease with increasing β.It is indicated that the change of connectivity is attributed to the difference of the membrane topology.It is shown that membrane pore size and connectivity can be controlled effectively by choosing proper α and β.
文摘利用英国Legion Studio 2006步行人流模拟软件为平台,以北京北苑交通枢纽方案设计为例,对北苑枢纽内部行人交通组织与空间换乘情况进行仿真模拟研究.仿真输出结果分别验证了现况天通苑北站及北苑枢纽设计方案中各项行人交通设施的不足点与合理之处,通过仿真模拟发现设计弊端,从而能够预先解决问题.随着计算机仿真技术在国际交通工程界的推广,微观人流仿真作为一种有效的研究方法,将更好地为综合交通枢纽规划与设计相关工作提供有力的技术支持与分析依据.
