【摘要】 用分子模拟研究有机分子在陶瓷膜中的扩散和吸附,以了解不同分子在膜表面和膜孔吸附和穿透的扩散行为。通常采用非平衡分子模拟方法,如巨正则系综蒙特卡洛方法或双系综分子动力学。Materials Studio(MS)软件只能用于微正则或正则系综的平衡分子动力学模拟(EMD)。为使其能计算非平衡分子动力学(EMD)计算,开发出1种恒压间歇分子动力学法(IBMD)。利用它去研究丙酮/氮气混合气穿透氧化铝膜的扩散和吸附行为,并和EMD比较。IBMD计算结果表明,温度升高,丙酮和氮气分子吸附和扩散速率加快;且不同孔径陶瓷膜呈现不同的吸附机理。证明IBMD法可行。更多还原

【Abstract】 The adsorbing and permeating behaviors of organic gases on the membrane surface and/or through the membrane channel can be investigated by molecular simulation.So far,the applied research techniques are commonly non-equilibrium molecular dynamics methods such as Grand Canonical Monte Carlo(GCMC) and Dual Ensemble Molecular Dynamics(DEMD).As known,Materials Studio (MS) software can only be used to perform equilibrium molecular simulation in micro canonical or canonical ensemble.To solve this problem,a new non-equilibrium moleclar simulation method called isobar batch molecular dynamics(IBMD) has been deveolped in this work.The diffusing and adsorbing behaviors of acetone and nitrogen mixed gas permeating through a ceramic membrane were investigated by IBMD and were compared with that by equilibrium molecular dynamics(EMD).The results reveal that IBMD is practicable.更多还原