分子的扩散行为是微观化学的重要研究领域. 影响扩散行为的因素很多，但是目前各个因素的具体影响效果还不明确. 作者基于随机行走理论建立了分子在二维空间的扩散模型，依据此模型自主开发了模拟软件以及数据分析系统，并利用该模拟软件系统研究了势垒尧横向速度等因素对扩散行为的影响，验证了该模型的可靠性，证明根据该模型可以得到和实验尧理论相吻合的结果. 该软件有望成为模拟微观化学扩散行为的潜在平台，如电化学以及膜过滤过程中的扩散.
赵建伟
,
陈莉莉
,
傅应强
,
黎绍鸿
,
陈天南
,
张世界
. 基于随机行走的二维空间扩散模拟研究[J]. 电化学, 2012
, 18(5)
: 427
-436
.
DOI: 10.61558/2993-074X.2613
Research on diffusion behaviors is of significant value in that it is closely related to transport phenomena in micro-chemistry. However, the effects of variables on diffusion are still unclear. Here, we developed and programmed a simulation methodology along with data analysis, which was capable to simulate the diffusion of a particle within twodimensional heterogeneous space in large timescale; the effects of periodically arranged impenetrable barriers of specific shape and lateral drifting velocity on diffusion behavior were studied. As well as standard mean square displacement analysis, a new method, the appearance probability distribution method, was introduced, which revealed whether the particle tended to be present at certain positions. This article introduced the construction of the simulation model and demonstrated the validity of the model. The results showed that our model fit qualitatively well with experiments and theories. The model was proved to be an excellent potential platform for simulating the diffusion behaviors in micro-chemistry, such as the diffusion process in electrochemistry as well as nanofiltration membrane.
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