Metal-organic frameworks（MOFs） are a unique class of porous crystalline materials that have shown promise for a wide range of applications. MOFs have been explored as a new type of heterogeneous catalytic materials,...Metal-organic frameworks（MOFs） are a unique class of porous crystalline materials that have shown promise for a wide range of applications. MOFs have been explored as a new type of heterogeneous catalytic materials, because of their high surface area, uniform and tunable pores, facile functionalization and incorporation of catalytic active sites. The use of multi-functional sites MOF materials as catalysts for synergistic catalysis and tandem reactions has attracted increasing attention. In this review, we aim to introduce the construction of bi-or multi-functional MOF catalysts with cooperative or cascade functions via post-synthetic modification（PSM）.展开更多
To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforc...To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforced polymer(CFRP)and aluminum components for a robotic aircraft assembly system.To meet the specific functional requirements for blind rivet installation on CFRP and aluminum materials,additional modules are incorporated on the end effector aside of the basic processing modules for drilling.And all of these processing modules allow for a onestep-drilling-countersinking process,hole inspection,automatic rivet feed,rivet geometry check,sealant application,rivet insertion and installation.Besides,to guarantee the better quality of the hole drilled and joints riveted,several online detection and adjustment measures are applied to this end effector,including the reference detection and perpendicular calibration,which could effectively ensure the positioning precision and perpendicular accuracy as demanded.Finally,the test result shows that this end effector is capable of producing each hole to a positioning precision within ±0.5 mm,aperpendicular accuracy within 0.3°,a diameter tolerance of H8,and a countersink depth tolerance of±0.01 mm.Moreover,it could drill and rivet up to three joints per minute,with acceptable shearing and tensile strength.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 21371069 and 21621001)
文摘Metal-organic frameworks（MOFs） are a unique class of porous crystalline materials that have shown promise for a wide range of applications. MOFs have been explored as a new type of heterogeneous catalytic materials, because of their high surface area, uniform and tunable pores, facile functionalization and incorporation of catalytic active sites. The use of multi-functional sites MOF materials as catalysts for synergistic catalysis and tandem reactions has attracted increasing attention. In this review, we aim to introduce the construction of bi-or multi-functional MOF catalysts with cooperative or cascade functions via post-synthetic modification（PSM）.
基金supported by the National Natural Science Foundations of China(Nos.5157051626,51475225)
文摘To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforced polymer(CFRP)and aluminum components for a robotic aircraft assembly system.To meet the specific functional requirements for blind rivet installation on CFRP and aluminum materials,additional modules are incorporated on the end effector aside of the basic processing modules for drilling.And all of these processing modules allow for a onestep-drilling-countersinking process,hole inspection,automatic rivet feed,rivet geometry check,sealant application,rivet insertion and installation.Besides,to guarantee the better quality of the hole drilled and joints riveted,several online detection and adjustment measures are applied to this end effector,including the reference detection and perpendicular calibration,which could effectively ensure the positioning precision and perpendicular accuracy as demanded.Finally,the test result shows that this end effector is capable of producing each hole to a positioning precision within ±0.5 mm,aperpendicular accuracy within 0.3°,a diameter tolerance of H8,and a countersink depth tolerance of±0.01 mm.Moreover,it could drill and rivet up to three joints per minute,with acceptable shearing and tensile strength.
