This work applies three theories (Film theory, Penetration theory and Boundary theory) to the experiment of two gases (NH_3 and HCl) which diffuse from both ends in a long tube. They can agree well with the results of experiments.
Yu, P. W. (2010). 噴射式氦/氧大氣電漿模擬研究-物理化學機制與特性、操作參數關聯性之探討與驗證 [master's thesis, National Tsing Hua University]. Airiti Library. https://www.airitilibrary.com/Article/Detail?DocID=U0016-1901201111392234