In the operation process of anion exchange membrane fuel cell,water molecules are working as the transmission medium of OH-.Therefore,hygroscopic property is one of the most important performances of anion exchange membranes,in addition to conductivity and alkali resistance stability.It is also the focus of research on the improvement of anion exchange membranes.In this paper,two series of anion exchange membranes for fuel cells based on metal organic framework (MOFs) materials were prepared, and their crystal structures and morphologies were characterized by XRD and SEM.In addition,the water content,swelling degree,swelling kinetics, and mechanical properties were tested and analyzed in detail.The results show that the water content,swelling degree, and mechanical properties of the two membranes are much different. Though the swelling kinetic behavior of the two prepared membranes follow Schott's second⁃order swelling kinetic equation,but exhibit different swelling behaviors,due to the different functions of the two component of MOFs.

In this paper, the adsorption behavior of polyoctadecyl acrylate (POA) in model crude oil on the surface of nano⁃SiO2 particles modified by methyl was investigated by performing molecular dynamics (MD) simulations. The adsorption model of model crude oil including POA molecule on the surface of nano⁃SiO ₂ particles was constructed. The model crude oil consists of asphaltene, resin, aromatic hydrocarbons and alkanes. The surface of nano⁃SiO ₂ particles was modified with three different degree of methyl. Several parameters such as the adsorption energy, relative density distribution, the mean square displacement and radial distribution function were analyzed. The results show that the unmodified surface is firstly adsorbed by asphaltene of strong polarity while the surface of 100% methyl⁃modified is firstly adsorbed by n⁃alkanes. The surface of 50% methyl⁃modified particles is firstly adsorbed by aromatic hydrocarbons. The results also indicate that the surface of 50% methyl⁃modified particles is not only more conducive to the stable adsorption of POA molecules, but also conducive to POA molecules to form a better adsorption configuration. What’ more, on the surface of 50% methyl⁃modified particles, the interaction between POA molecule and C ₂₄H ₅₀ molecules is stronger, and the distribution of C ₂₄H ₅₀ molecules is more aggregated. Finally, the study of this paper provides a method for studying the mechanism of pour point depressants composed of polymer and inorganic nanoparticle and provides theoretical guidance for the experimental modification of nanometer particles in nano⁃hybrid pour point depressant.

A new method was proposed to measure the thickness of the boundary layer, and the thickness of the boundary layer under different viscosity and different pressure gradient was measured. The research results show that under the same pore throat radius and pressure gradient, the relation between the viscosity of the fluid and the proportion of the boundary layer is linear. The greater the viscosity, the greater the proportion of the boundary layer. Under the same viscosity and pressure gradient, with the increase of pore throat radius, the proportion of the boundary layer decreases rapidly. Under the same viscosity and pore throat radius, with the increase of the pressure gradient, boundary layer ratio decreases and tends to be stable. In addition by drawing the boundary layer thickness ratio chart, the influence of viscosity and displacement pressure gradient on nonlinear seepage is analyzed, and the results further confirme that the boundary layer is the fundamental reason for the nonlinear flow characteristics in tight oil cores.