We adopted LBGK model of heat-mass coupling in lattice Boltzmann method to simulate double diffusion mixed convection, fluid-solid conjugate heat transfer and adsorption process in an enclosure filled with spherical activated carbon with real physical parameters at pore scale. D2Q9 model was used to describe velocity and temperature fields, and D2Q5 for concentration fields, respectively. Impact of activated carbon particle size, porosity and particle arrangement on entire dynamic adsorption performance was investigated. It shows that with increased activated carbon particle size the time to approach steady is increased and the adsorption rate is moderated at porosity 0.85. At particle diameter 0.43 mm, the adsorption rate is the highest and the adsorption time is the shortest. Transient adsorption capability and time consumption to equilibrium were independent of filling rate. Compared with those of line and dislocation arrangement of activated carbon particles, transient adsorption capability of random and non-adherent arrangement is better.

Carbon doping in Mn₃Ge was studied with first-principles calculations. Firstly, geometry optimization was performed on crystal structure of Mn_3-xGeC_x. It was found that the most stable doping position of carbon is at the center of regular octahedron. We studied total magnetic moment of Mn_3-xGeC_x. The total magnetic moment decreases firstly and then increases as carbon concentration increasing. We found that the total magnetic moment of Mn₃GeC_0.4 is almost zero, in which complete magnetic compensation can be realized. In addition, magnetic properties of Mn₃GeC_0.4 multilayers were investigated. Crystal structure of Mn₃GeC_0.4 multilayers with total magnetic moment close to zero is shown. It provides references for practical application of Mn₃Ge.