The infections in open fracture induce high morbidity worldwide.Thus,developing efficient anti-infective orthopedic devices is of great significance.In this work,we designed a kind of infection-responsive long-term an...The infections in open fracture induce high morbidity worldwide.Thus,developing efficient anti-infective orthopedic devices is of great significance.In this work,we designed a kind of infection-responsive long-term antibacterial bone plates.Through a facile and flexible volatilization method,a multi-aldehyde polysaccharide derivative,oxidized sodium alginate,was crosslinked with multi-amino compounds,gentamycin and gelatin,to fabricate a uniform coating on Ti bone plates via Schiff base reaction,which was followed by a secondary crosslinking process by glutaraldehyde.The double-crosslinked coating was stable under normal condition,and could responsively release gentamycin by the triggering of the acidic microenvironment caused by bacterial metabolism,owning to the pH-responsiveness of imine structure.The thickness of the coating was ranging from 22.0μm to 63.6μm.The coated bone plates(Ti-GOGs)showed infection-triggered antibacterial properties(>99%)and high biocompatibility.After being soaked for five months,it still possessed efficient antibacterial ability,showing its sustainable antibacterial performance.The in vivo anti-infection ability was demonstrated by an animal model of infection after fracture fixation(IAFF).At the early stage of IAFF,Ti-GOGs could inhibit the bacterial infection(>99%).Subsequently,Ti-GOGs could promote recovery of fracture of IAFF.This work provides a convenient and universal strategy for fabrication of various antibacterial orthopedic devices,which is promising to prevent and treat IAFF.展开更多
Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon ox...Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon oxide etch and strip,are contained.To acquire good performance,such as low leakage current and high capacitance,for further fabricating capacitors,we should firstly optimize DARC etch back.We developed some experiments,focusing on etch time and chemistry,to evalu-ate the profile of a silicon oxide mask,DARC remain and critical dimension.The result shows that etch back time should be con-trolled in the range from 50 to 60 s,based on the current equipment and condition.It will make B/T ratio higher than 70%mean-while resolve the DARC remain issue.We also found that CH_(2)F_(2) flow should be~15 sccm to avoid reversed CD trend and keep in-line CD.展开更多
In this study, Y-and Ce-modified Cr coatings applied by pack cementation method were prepared on the surface of open-cell nickel-based alloy foam. The morphologies and microstructures of Y- and Ce-modified Cr coatings...In this study, Y-and Ce-modified Cr coatings applied by pack cementation method were prepared on the surface of open-cell nickel-based alloy foam. The morphologies and microstructures of Y- and Ce-modified Cr coatings with various Y and Ce contents were investigated in detail. Then, the effects of Y and Ce addition on the mechanical properties of open-cell nickel-based alloy foams were analyzed and compared. Simultaneously, the energy absorption capacity and energy absorption efficiency of the Y- and Ce-modified Cr coated alloy foams were discussed and compared at the room and high temperatures. The results show that Cr coatings containing minor amounts of rare earth element （Y and Ce） are well adhered to the nickel-based foam struts. Especially, the microstructure of the 2 wt% Ce-modified Cr coating is denser and uniform. In addition, the compressive strength and plateau stress of Y- and Ce-modified Cr coated alloy foams firstly increase and then decrease by increasing the Y and Ce contents at room and high temperatures. The energy absorption capacity of Y/Cr and Ce/Cr coated alloy foams increases linearly with the strains increasing. The Ce/Cr coated alloy foams can absorb more energy than Y/Cr coated alloy foams in the plateau and densification regions at room temperature. Compared to those at room temperature, the Y- and Ce-modified Cr coated alloy foams show higher energy absorption efficiency when deforma- tion within 10%-30% at high temperature.展开更多
基金This work was supported by National Natural Science Foundation of China[Grant Nos.52122304,52073024 and 51873012]Beijing Outstanding Young Scientist Program[Grant No.BJJWZYJH01201910010024]Chinese Association of Rehabilitation Medicine Technology Development Project[Grant No.KFKT-2022-002].
文摘The infections in open fracture induce high morbidity worldwide.Thus,developing efficient anti-infective orthopedic devices is of great significance.In this work,we designed a kind of infection-responsive long-term antibacterial bone plates.Through a facile and flexible volatilization method,a multi-aldehyde polysaccharide derivative,oxidized sodium alginate,was crosslinked with multi-amino compounds,gentamycin and gelatin,to fabricate a uniform coating on Ti bone plates via Schiff base reaction,which was followed by a secondary crosslinking process by glutaraldehyde.The double-crosslinked coating was stable under normal condition,and could responsively release gentamycin by the triggering of the acidic microenvironment caused by bacterial metabolism,owning to the pH-responsiveness of imine structure.The thickness of the coating was ranging from 22.0μm to 63.6μm.The coated bone plates(Ti-GOGs)showed infection-triggered antibacterial properties(>99%)and high biocompatibility.After being soaked for five months,it still possessed efficient antibacterial ability,showing its sustainable antibacterial performance.The in vivo anti-infection ability was demonstrated by an animal model of infection after fracture fixation(IAFF).At the early stage of IAFF,Ti-GOGs could inhibit the bacterial infection(>99%).Subsequently,Ti-GOGs could promote recovery of fracture of IAFF.This work provides a convenient and universal strategy for fabrication of various antibacterial orthopedic devices,which is promising to prevent and treat IAFF.
文摘Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon oxide etch and strip,are contained.To acquire good performance,such as low leakage current and high capacitance,for further fabricating capacitors,we should firstly optimize DARC etch back.We developed some experiments,focusing on etch time and chemistry,to evalu-ate the profile of a silicon oxide mask,DARC remain and critical dimension.The result shows that etch back time should be con-trolled in the range from 50 to 60 s,based on the current equipment and condition.It will make B/T ratio higher than 70%mean-while resolve the DARC remain issue.We also found that CH_(2)F_(2) flow should be~15 sccm to avoid reversed CD trend and keep in-line CD.
基金financially supported by the National Natural Science Foundation of China (Nos.51501133 and 51405358)the China Automobile Industry Innovation and Development Joint Fund (No.U1564202)+1 种基金the Natural Science Foundation of Hubei Province (No.2016CFC773)the State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology (No.AWJ-M16-11)
文摘In this study, Y-and Ce-modified Cr coatings applied by pack cementation method were prepared on the surface of open-cell nickel-based alloy foam. The morphologies and microstructures of Y- and Ce-modified Cr coatings with various Y and Ce contents were investigated in detail. Then, the effects of Y and Ce addition on the mechanical properties of open-cell nickel-based alloy foams were analyzed and compared. Simultaneously, the energy absorption capacity and energy absorption efficiency of the Y- and Ce-modified Cr coated alloy foams were discussed and compared at the room and high temperatures. The results show that Cr coatings containing minor amounts of rare earth element （Y and Ce） are well adhered to the nickel-based foam struts. Especially, the microstructure of the 2 wt% Ce-modified Cr coating is denser and uniform. In addition, the compressive strength and plateau stress of Y- and Ce-modified Cr coated alloy foams firstly increase and then decrease by increasing the Y and Ce contents at room and high temperatures. The energy absorption capacity of Y/Cr and Ce/Cr coated alloy foams increases linearly with the strains increasing. The Ce/Cr coated alloy foams can absorb more energy than Y/Cr coated alloy foams in the plateau and densification regions at room temperature. Compared to those at room temperature, the Y- and Ce-modified Cr coated alloy foams show higher energy absorption efficiency when deforma- tion within 10%-30% at high temperature.
