PVC disulfide （2SPVC） was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC＇s specific area is 36.1 m^2·g^-1 tested by stand BET method, and granularity ex...PVC disulfide （2SPVC） was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC＇s specific area is 36.1 m^2·g^-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5 = 11.3 μm. With SEM （Scanning Electron Microscope） experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry （scan rate： 0.5 mV · s^-1） shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L^-1 solution of lithium bis（trifluoromethylsulfonyl） imide （Li（CF3SO2）2N） in a 5：45：50 volume ratio mixture of o-xylene （oxy）, diglyme （DG） and dimethoxymethane （DME） at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g^-1 which is very close to its theoretical value （410.5 mAh ·g^-1） at a constant discharge current of 15 mA·g^-1. It can retain at about 346.1 mAh ·g^-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.展开更多
Cable-type welding wire（CWW）CO2 welding is an innovative process arc welding with high quality,high efficiency and energy saving,in which CWW is used as consumable electrode.The CWW is composed of seven wires with a...Cable-type welding wire（CWW）CO2 welding is an innovative process arc welding with high quality,high efficiency and energy saving,in which CWW is used as consumable electrode.The CWW is composed of seven wires with a diameter of 1.2mm.One is in the center,while others uniformly distribute around it.The diameter of twisted wire is up to 3.6mm,which can increase the deposition rate significantly.With continual wire-feeding and melting of CWW,the formed rotating arc improved welding quality obviously.The arc behavior and droplet transfer were observed by the electrical signal waveforms and corresponding synchronous images,based on the high speed digital camera and electrical signal system.The results showed that the shape of welding arc changed from bell arc to beam arc with the increase of welding parameter.The droplet transfer mode changed from repelled transfer,globular transfer to projected transfer in turn.Droplet transfer frequency increased from 18.17 Hz to 119.05 Hz,while the droplet diameter decreased from 1.5times to 0.3times of the CWW diameter.展开更多
文摘PVC disulfide （2SPVC） was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC＇s specific area is 36.1 m^2·g^-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5 = 11.3 μm. With SEM （Scanning Electron Microscope） experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry （scan rate： 0.5 mV · s^-1） shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L^-1 solution of lithium bis（trifluoromethylsulfonyl） imide （Li（CF3SO2）2N） in a 5：45：50 volume ratio mixture of o-xylene （oxy）, diglyme （DG） and dimethoxymethane （DME） at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g^-1 which is very close to its theoretical value （410.5 mAh ·g^-1） at a constant discharge current of 15 mA·g^-1. It can retain at about 346.1 mAh ·g^-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.
基金Item Sponsored by National Natural Science Foundation of China(51275224,51575250,51505200)Prospective Joint Research Project of Jiangsu Province of China(BY2015065-06)Priority Academic Program Development of Jiangsu Higher Education Institutions of China
文摘Cable-type welding wire（CWW）CO2 welding is an innovative process arc welding with high quality,high efficiency and energy saving,in which CWW is used as consumable electrode.The CWW is composed of seven wires with a diameter of 1.2mm.One is in the center,while others uniformly distribute around it.The diameter of twisted wire is up to 3.6mm,which can increase the deposition rate significantly.With continual wire-feeding and melting of CWW,the formed rotating arc improved welding quality obviously.The arc behavior and droplet transfer were observed by the electrical signal waveforms and corresponding synchronous images,based on the high speed digital camera and electrical signal system.The results showed that the shape of welding arc changed from bell arc to beam arc with the increase of welding parameter.The droplet transfer mode changed from repelled transfer,globular transfer to projected transfer in turn.Droplet transfer frequency increased from 18.17 Hz to 119.05 Hz,while the droplet diameter decreased from 1.5times to 0.3times of the CWW diameter.
