A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis (FEA) model has been developed to describe th...A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis (FEA) model has been developed to describe the static and dynamic operations of the valves. Compared with a conventional E-type actuator, the proposed ε-type actuator reduced the moving mass weight by almost 65% without significant loss of solenoid force, and reduced the response time (RT) typically by 20%. Prototype valves were designed and fabricated based on the proposed ε-type actuator model. An experimental setup was also established to investigate the dynamic characteristics of valves. The experimental results of the dynamics of valves agreed well with simulations, indicating the validity of the FEA model.展开更多
Recent studies have shown the potential of artificially synthesized conduits in the repair of peripheral nerve injury.Natural biopolymers have received much attention because of their biocompatibility.To investigate t...Recent studies have shown the potential of artificially synthesized conduits in the repair of peripheral nerve injury.Natural biopolymers have received much attention because of their biocompatibility.To investigate the effects of novel electrospun absorbable poly(ε-caprolactone)/type I collagen nanofiber conduits(biopolymer nanofiber conduits)on the repair of peripheral nerve injury,we bridged 10-mm-long sciatic nerve defects with electrospun absorbable biopolymer nanofiber conduits,poly(ε-caprolactone)or silicone conduits in Sprague-Dawley rats.Rat neurologica1 function was weekly evaluated using sciatic function index within 8 weeks after repair.Eight weeks after repair,sciatic nerve myelin sheaths and axon morphology were observed by osmium tetroxide staining,hematoxylin-eosin staining,and transmission electron microscopy.S-100(Schwann cell marker)and CD4(inflammatory marker)immunoreactivities in sciatic nerve were detected by immunohistochemistry.In rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits,no serious inflammatory reactions were observed in rat hind limbs,the morphology of myelin sheaths in the injured sciatic nerve was close to normal.CD4 immunoreactivity was obviously weaker in rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits than in those subjected to repair with poly(ε-caprolactone)or silicone.Rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits tended to have greater sciatic nerve function recovery than those receiving poly(ε-caprolactone)or silicone repair.These results suggest that electrospun absorbable poly(ε-caprolactone)/type I collagen nanofiber conduits have the potential of repairing sciatic nerve defects and exhibit good biocompatibility.All experimental procedures were approved by Institutional Animal Care and Use Committee of Taichung Veteran General Hospital,Taiwan,China(La-1031218)on October 2,2014.展开更多
基金Project supported by the Doctoral Fund of Ministry of Education of China (No. 20070335133)the Educational Commission of Zhejiang Province (No. 20070057), China
文摘A novel ε-type solenoid actuator is proposed to improve the dynamic response of electro-pneumatic ejector valves by reducing moving mass weight. A finite element analysis (FEA) model has been developed to describe the static and dynamic operations of the valves. Compared with a conventional E-type actuator, the proposed ε-type actuator reduced the moving mass weight by almost 65% without significant loss of solenoid force, and reduced the response time (RT) typically by 20%. Prototype valves were designed and fabricated based on the proposed ε-type actuator model. An experimental setup was also established to investigate the dynamic characteristics of valves. The experimental results of the dynamics of valves agreed well with simulations, indicating the validity of the FEA model.
基金supported by grants from the Taichung Veterans General Hospital and Central Taiwan University of Science and Technology,No.TCVGH-CTUST1047701(to CCS and BSL)Taichung Veterans General Hospital,No.TCVGH-1034907C(to CCS),Taiwan,China
文摘Recent studies have shown the potential of artificially synthesized conduits in the repair of peripheral nerve injury.Natural biopolymers have received much attention because of their biocompatibility.To investigate the effects of novel electrospun absorbable poly(ε-caprolactone)/type I collagen nanofiber conduits(biopolymer nanofiber conduits)on the repair of peripheral nerve injury,we bridged 10-mm-long sciatic nerve defects with electrospun absorbable biopolymer nanofiber conduits,poly(ε-caprolactone)or silicone conduits in Sprague-Dawley rats.Rat neurologica1 function was weekly evaluated using sciatic function index within 8 weeks after repair.Eight weeks after repair,sciatic nerve myelin sheaths and axon morphology were observed by osmium tetroxide staining,hematoxylin-eosin staining,and transmission electron microscopy.S-100(Schwann cell marker)and CD4(inflammatory marker)immunoreactivities in sciatic nerve were detected by immunohistochemistry.In rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits,no serious inflammatory reactions were observed in rat hind limbs,the morphology of myelin sheaths in the injured sciatic nerve was close to normal.CD4 immunoreactivity was obviously weaker in rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits than in those subjected to repair with poly(ε-caprolactone)or silicone.Rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits tended to have greater sciatic nerve function recovery than those receiving poly(ε-caprolactone)or silicone repair.These results suggest that electrospun absorbable poly(ε-caprolactone)/type I collagen nanofiber conduits have the potential of repairing sciatic nerve defects and exhibit good biocompatibility.All experimental procedures were approved by Institutional Animal Care and Use Committee of Taichung Veteran General Hospital,Taiwan,China(La-1031218)on October 2,2014.
