Utilizing a facile top-down synthetic procedure, here we report the finding of a chlorine-passivated Al_(37) superatom cluster. It is demonstrated that the presence of electrophilic groups, severing as protecting liga...Utilizing a facile top-down synthetic procedure, here we report the finding of a chlorine-passivated Al_(37) superatom cluster. It is demonstrated that the presence of electrophilic groups, severing as protecting ligands, alters the valence electron count of the metallic core and stabilize the as-prepared aluminum clusters especially when even-numbered chlorine atoms are located at equilibrium positions. Following the discussion regarding their reasonable stabilities, we illustrate the feasible reaction pathways in forming such chlorine-passivated Al_(37) superatom clusters which bear delocalized superatomic orbitals with five valence 3P^5 electrons shifting to the chlorine ligands indicative of a closed electron shell 2F^(14) of the metal core. The successful synthesis of such chlorine-protected aluminum clusters evidences the compatibility of general theory of cluster chemistry in both gas phase and wet chemistry. Such simple-ligand-protected aluminum clusters exhibit reverse-saturated-absorption(RSA) nonlinear optical property pertaining to electronic transitions within the discrete energy states of cluster materials.展开更多
The morphologies evolution of various types of inclusions in Ti-IF steel were observed by a special depth erosion method,and the formation and evolution process were discussed.The results showed that the main inclusio...The morphologies evolution of various types of inclusions in Ti-IF steel were observed by a special depth erosion method,and the formation and evolution process were discussed.The results showed that the main inclusions were FeO·xMnO before Al deoxidization and the ratio of integrated oxygen and free oxygen was in ranged of 0.3 to 0.4.In present study,the main effect factors on the morphologies of Al_2O_3 inclusions were [Al]/[O]_(Free)(soluble aluminum divide free oxygen) and initial free oxygen;cluster Al_2O_3 was formed easily with high free oxygen([O]_(Free)) and low[Al]/[O](blew 3 in present study).Otherwise,the dendritic Al_2O_3 was formed;coral-like Al_2O_3 was the mixture of the dendrite Al_2O_3 and spherical Al_2O_3.Some Al_2O_3·TiO_x inclusions appeared because a high[Ti]concentration region existed around 70TiFe(containing 70 percent titanium) particles after 70TiFe addition.The maximum sizes of Al_2O_3 reached 800μm when 3 min aluminum was added;as the time past,the large size Al_2O_3 decreased significantly;the maximum size of Al_2O_3 was blew 100μm and 50μm in calming sample and tundish sample respectively.展开更多
基金supported by the Key Research Program of Frontier Sciences (QYZDB-SSW-SLH024)the National Natural Science Foundation of China (21722308)the National Thousand Youth Talents Program
文摘Utilizing a facile top-down synthetic procedure, here we report the finding of a chlorine-passivated Al_(37) superatom cluster. It is demonstrated that the presence of electrophilic groups, severing as protecting ligands, alters the valence electron count of the metallic core and stabilize the as-prepared aluminum clusters especially when even-numbered chlorine atoms are located at equilibrium positions. Following the discussion regarding their reasonable stabilities, we illustrate the feasible reaction pathways in forming such chlorine-passivated Al_(37) superatom clusters which bear delocalized superatomic orbitals with five valence 3P^5 electrons shifting to the chlorine ligands indicative of a closed electron shell 2F^(14) of the metal core. The successful synthesis of such chlorine-protected aluminum clusters evidences the compatibility of general theory of cluster chemistry in both gas phase and wet chemistry. Such simple-ligand-protected aluminum clusters exhibit reverse-saturated-absorption(RSA) nonlinear optical property pertaining to electronic transitions within the discrete energy states of cluster materials.
文摘The morphologies evolution of various types of inclusions in Ti-IF steel were observed by a special depth erosion method,and the formation and evolution process were discussed.The results showed that the main inclusions were FeO·xMnO before Al deoxidization and the ratio of integrated oxygen and free oxygen was in ranged of 0.3 to 0.4.In present study,the main effect factors on the morphologies of Al_2O_3 inclusions were [Al]/[O]_(Free)(soluble aluminum divide free oxygen) and initial free oxygen;cluster Al_2O_3 was formed easily with high free oxygen([O]_(Free)) and low[Al]/[O](blew 3 in present study).Otherwise,the dendritic Al_2O_3 was formed;coral-like Al_2O_3 was the mixture of the dendrite Al_2O_3 and spherical Al_2O_3.Some Al_2O_3·TiO_x inclusions appeared because a high[Ti]concentration region existed around 70TiFe(containing 70 percent titanium) particles after 70TiFe addition.The maximum sizes of Al_2O_3 reached 800μm when 3 min aluminum was added;as the time past,the large size Al_2O_3 decreased significantly;the maximum size of Al_2O_3 was blew 100μm and 50μm in calming sample and tundish sample respectively.
