The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steel...The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steels remain martensite structures and have anodic dissolution characteristic with an increase of chromium content. There is no typical passive region on the polarization curves of an ultra high strength stainless steel, AerMet 100 steel, and 300M steel. However, chromium improves the corrosion resistance of the stainless steel remarkably. It has the slowest corrosion rate in the salt spray test, one order of magnitude less than that of AerMet 100 and 300M steels. With the increase of chromium content, the polarization resistance becomes larger, the corrosion potential shifts towards the positive direction with a value of 545 mV, and the corrosion current density decreases in electrochemical measures in 3.5wt% NaCl solutions. Because of the higher content of chromium, the ultra high strength stainless steel has a better corrosion resistance than AerMet 100 and 300M steels.展开更多
BACKGROUND Subclavian vein stenosis or occlusion may be caused by a transvenous pacemaker,which makes the reimplantation of a new pacemaker lead difficult.Transvenous pacemaker lead implantation-related subclavian vei...BACKGROUND Subclavian vein stenosis or occlusion may be caused by a transvenous pacemaker,which makes the reimplantation of a new pacemaker lead difficult.Transvenous pacemaker lead implantation-related subclavian vein occlusion may present difficulty with regard to cardiac resynchronization therapy(CRT)upgrade.CASE SUMMARY We report the case of a 46-year-old man who was admitted with total subclavian vein occlusion caused by a permanent pacemaker that had been implanted 2 years previously.We successfully treated this patient with an upgrade to a CRT pacemaker by utilizing transferable interventional coronary and radiological techniques.The patient recovered uneventfully during the follow-up period.CONCLUSION CRT upgrade is still a viable technique for the treatment of subclavian vein obstruction caused by previous pacemaker implantation.展开更多
基金supported by the National Science and Technology Infrastructure Platforms Construction Projects of China (Grant No2005DKA10400)the National Science Foundation of China (No50871021)
文摘The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steels remain martensite structures and have anodic dissolution characteristic with an increase of chromium content. There is no typical passive region on the polarization curves of an ultra high strength stainless steel, AerMet 100 steel, and 300M steel. However, chromium improves the corrosion resistance of the stainless steel remarkably. It has the slowest corrosion rate in the salt spray test, one order of magnitude less than that of AerMet 100 and 300M steels. With the increase of chromium content, the polarization resistance becomes larger, the corrosion potential shifts towards the positive direction with a value of 545 mV, and the corrosion current density decreases in electrochemical measures in 3.5wt% NaCl solutions. Because of the higher content of chromium, the ultra high strength stainless steel has a better corrosion resistance than AerMet 100 and 300M steels.
基金The Ningbo Natural Science Foundation of China,No.2019A610342the Ningbo Health Branding Subject Fund,No.PPXK2018-01.
文摘BACKGROUND Subclavian vein stenosis or occlusion may be caused by a transvenous pacemaker,which makes the reimplantation of a new pacemaker lead difficult.Transvenous pacemaker lead implantation-related subclavian vein occlusion may present difficulty with regard to cardiac resynchronization therapy(CRT)upgrade.CASE SUMMARY We report the case of a 46-year-old man who was admitted with total subclavian vein occlusion caused by a permanent pacemaker that had been implanted 2 years previously.We successfully treated this patient with an upgrade to a CRT pacemaker by utilizing transferable interventional coronary and radiological techniques.The patient recovered uneventfully during the follow-up period.CONCLUSION CRT upgrade is still a viable technique for the treatment of subclavian vein obstruction caused by previous pacemaker implantation.