The conductive oxide impact on Aluminum alloy of YAG pulse laser welding
Few articles are reported about conductive oxide impacting on Aluminum alloy of Nd: YAG pulse laser welding at present. Therefore, this paper takes one typical Aluminum alloy as laser welding samples. Through SEM (scanning electron microscope) microscopic analysis and contrast, the comparative study between on with and without surface conductive oxidation impacting on laser welding samples have been conducted. The results show that the laser welding process parameters are needed, but the conductive oxide will bring no destructive effect on laser welding. Accordingly for this reason, it is thought that the conductive oxide will not bring substantial effect on Aluminum alloy of Nd: YAG pulse laser welding.
Study on Laser Welding of 1420 Aluminum-lithium Alloy
The reasons causing main defects of 1420 aluminum-lithium alloy were analyzed.The influences of the laser welding process parameters on the formation and welding were elaborated.The aluminum-lithium alloy development and the trend of the future were projected.
An Ultrasensitive Analytical Method Based on Chemiluminescence Sensing Electrochemical Parallel Catalytic Reaction Event
An ultrasensitive electrochemiluminescence (ECL) method on the combination of electrochemical parallel catalytic reaction and chemiluminesence signal sensing was proposed for improving ECL analytical characteristics using vanadate(V) as a representative. Vanadate(V) could be electrochemically reduced to generate vanadate(II) which could be chemically oxidized by potassium periodate to regenerate vanadate(V) and give parallel catalytic wave effect. Then, the reduced product of potassium periodate could react with butyl-rhodamine B to emit a sensitive chemiluminescence signal. The chemiluminescence intensity was correlative with vanadate(V) concentration. The investigation on the electrochemical reaction rate constant (k0) confirmed that the speed of electrochemical reaction was faster than that of the subsequent chemiluminescence reaction. The possibility of the combination of electrochemical parallel catalytic reaction with chemiluminescence signal sensing was proved. The similar ECL behaviors could be observed at zirconia nanowires-Nafion modified electrode. Because of the separation and enrichment effect of the modified electrode on vanadate(V), the selectivity and sensitivity was further improved greatly. Based on these findings, a new concept on the combination of electrochemical parallel catalytic reaction and chemiluminesence signal sensing was proposed and an ultrasensitive ECL method for the determination of vanadate(V) was developed at zirconia nanowires-Nafion modified electrode. Under the optimum experimental conditions, the ECL intensity was linear with the concentration of vanadate(V) in the range of 2.0×10−12 mol/L–2.0×10−10 mol/L. The detection limit was 8.0×10−13 mol/L, which was more than 6 orders of magnitude lower than that observed by electrochemical current transduction for electrochemical parallel catalytic reaction at zirconia nanowires-Nafion modified electrode.