半自动圆盘焊机的设计与应用

为提高焊接效率,焊接质量,降低成本设计了该半自动圆盘焊台。焊台由支架、电动机、减速器、皮带传动机构、夹具、圆盘等组成。焊台用电动机提供动力,通过减速器的减速,皮带轮传递动力使大圆盘带动工件以不超过0.44 r/min的转速转动,工件通过定位法兰和大圆盘定位,焊枪由夹具夹紧并固定指向摆线针轮减速机焊缝,随着焊件的转动从而将环形焊缝焊接。焊台主要用与辅助焊机焊接直径在45~360 mm的圆筒及管道的圆形焊缝,从而避免了人工操作焊时焊缝的不均匀性,人工焊时焊接路线的不准确性,从而提高了焊接质量,焊接效率,减少不必要的损失。     

Preparation of Antibacterial Electrospun PVA/Regenerated Silk Fibroin Nanofibrous Composite Containing Ciprofloxacin Hydrochloride as a Wound Dressing

Electrospinning technique was used for the fabrication of poly （ vinyl alcohol ） （ PVA ） / regenerated silk fibrnin （ SF ） composite nanofibers, loaded with ciprofloxacin HCI （CipHCI） as a wound dressing. Electrospun PVA/SF/CipHCI composite nanofibers were stabilized against dissolving in water by heating in an oven at 155℃ for 5 min. Incorporation of CipHCi into electrospun nanofibers was confirmed by SEM and FT.IR spectra. Further the mechanical properties test illustrated that the addition of CipHCI enhanced the mechanical properties of PVA and PVA/SF nanofibers. The antibacterial activities against Escherichia coU （E. coli ） （ gram-negative ） and Staphylococcus aureus （ S. aureus ） （gram-positive） organisms were evaluated by disk diffusion method; and results suggested that electrospun PVA/CipHCI and PVA/SF/ CipHCI composite nanofibers showed a remarkable antibacterial activity.