Size hierarchy is a distinct feature of nanogold-catalysts as it can strongly affect their performance in various reactions. We developed a simple method to generate Au n S m nanoclusters of different sizes by thermal...Size hierarchy is a distinct feature of nanogold-catalysts as it can strongly affect their performance in various reactions. We developed a simple method to generate Au n S m nanoclusters of different sizes by thermal treatment of an Au144(PET)60 (PET: phenylethanethiol) parent cluster. These clusters, deposited on activated carbon, exhibit excellent catalytic performance in the hydrochlorination of acetylene. In-situ ultraviolet laser dissociation high-resolution mass spectrometry of the parent cluster in the presence of acetylene revealed a remarkable cluster size-dependence of acetylene adsorption, which is a crucial step in the hydrochlorination. Systematic density functional theory calculations of the reaction pathways on the differently-sized clusters provide deeper insight into the cluster size dependence of the adsorption energies of the reactants and afforded a scaling relationship between the adsorption energy of acetylene and the co-adsorption energies of the reactants (C_(2)H_(2) and HCl), which could enable a qualitative prediction of the optimal Au n S m cluster for the hydrochlorination of acetylene.展开更多
We investigate an optimal control problem for a hierarchical size-structured populationmodel,which incorporates the inoculation delay into the globally feedbacked boundarycondition.After the establishment of the conti...We investigate an optimal control problem for a hierarchical size-structured populationmodel,which incorporates the inoculation delay into the globally feedbacked boundarycondition.After the establishment of the continuity of the states with respect to theharvesting efforts,the existence of the optimal solutions is proved by a result in convexanalysis,and the maximum principle is obtained via conjugate system and tangent-normal cones.展开更多
基金financial support by the National Natural Science Foundation of China(No.22172167).
文摘Size hierarchy is a distinct feature of nanogold-catalysts as it can strongly affect their performance in various reactions. We developed a simple method to generate Au n S m nanoclusters of different sizes by thermal treatment of an Au144(PET)60 (PET: phenylethanethiol) parent cluster. These clusters, deposited on activated carbon, exhibit excellent catalytic performance in the hydrochlorination of acetylene. In-situ ultraviolet laser dissociation high-resolution mass spectrometry of the parent cluster in the presence of acetylene revealed a remarkable cluster size-dependence of acetylene adsorption, which is a crucial step in the hydrochlorination. Systematic density functional theory calculations of the reaction pathways on the differently-sized clusters provide deeper insight into the cluster size dependence of the adsorption energies of the reactants and afforded a scaling relationship between the adsorption energy of acetylene and the co-adsorption energies of the reactants (C_(2)H_(2) and HCl), which could enable a qualitative prediction of the optimal Au n S m cluster for the hydrochlorination of acetylene.
基金This work was supported by the National Natural Science Foundation of China(11871185)Zhejiang Provincial Natural Science Foundation of China(LY18A010010).
文摘We investigate an optimal control problem for a hierarchical size-structured populationmodel,which incorporates the inoculation delay into the globally feedbacked boundarycondition.After the establishment of the continuity of the states with respect to theharvesting efforts,the existence of the optimal solutions is proved by a result in convexanalysis,and the maximum principle is obtained via conjugate system and tangent-normal cones.
