Effect of electrode insulation on the electric field and the flow field of the machining gap during electrochemical drilling（ECD） is numerically studied. Electric field simulation shows that the current density alon...Effect of electrode insulation on the electric field and the flow field of the machining gap during electrochemical drilling（ECD） is numerically studied. Electric field simulation shows that the current density along the side gap decreases with increasing the thickness of electrode insulation. And the analysis of the electrolyte flow in the frontal gap shows that the insulation thickness has a remarkable influence on the pressure distributions. Ex- periments investigate the influence of the insulation thickness on the main characteristics of the machined hole, i.e. , radial overcut, entrance conicity, and current stability. The poor hole is observed and identified as most likely to occur with a combination of the low tool feed rate and the low insulation thickness. The appropriate thickness of the insulating layer leads to an improvement on hole accuracy and machining stability.展开更多
Antibiotic abuse in food processing could threaten human health via either direct pathogen or drug-resistant infection.To curb this situation,it is of vital significance to identify trace level of antibiotics in foods...Antibiotic abuse in food processing could threaten human health via either direct pathogen or drug-resistant infection.To curb this situation,it is of vital significance to identify trace level of antibiotics in foodstuffin a point-of-care inspection manner.Here,a smartphone-based electrochemical system was developed for the quantitation of chloramphenicol(CAP).The differential pulse voltammetric reduction of CAP was measured facilely on a piece of gold-deposited screen-printed electrode,which was docked onto a palm-sized detector with remote directives from a mobile APP of Bluetooth handshaking and digital display.Under optimal conditions,the target CAP could be determined in a range from 1 nmol/L to 5μmol/L with a detection limit of 0.25 nmol/L.Further tests on emulate samples demonstrated the miniaturized device could handle the food-screening scenarios with accuracy,convenience and quick response.展开更多
基金Supported by the National Natural Science Foundation of China(50635040)the National High Technology Research and Development Program of China("863"Program)(2006AA04Z321)the Natural Science Foundation of Jiangsu Province(BK2008043)~~
文摘Effect of electrode insulation on the electric field and the flow field of the machining gap during electrochemical drilling（ECD） is numerically studied. Electric field simulation shows that the current density along the side gap decreases with increasing the thickness of electrode insulation. And the analysis of the electrolyte flow in the frontal gap shows that the insulation thickness has a remarkable influence on the pressure distributions. Ex- periments investigate the influence of the insulation thickness on the main characteristics of the machined hole, i.e. , radial overcut, entrance conicity, and current stability. The poor hole is observed and identified as most likely to occur with a combination of the low tool feed rate and the low insulation thickness. The appropriate thickness of the insulating layer leads to an improvement on hole accuracy and machining stability.
基金financially supported by the National Key Research and Development Program of China for International Science&Innovation Cooperation Major Project between Governments(2018YFE0113200)National Natural Science Foundation of China(21874071,22104058)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX21_0281)Fundamental Research Funds for the Central Universities(30921013112,30920021125,30922010501)
文摘Antibiotic abuse in food processing could threaten human health via either direct pathogen or drug-resistant infection.To curb this situation,it is of vital significance to identify trace level of antibiotics in foodstuffin a point-of-care inspection manner.Here,a smartphone-based electrochemical system was developed for the quantitation of chloramphenicol(CAP).The differential pulse voltammetric reduction of CAP was measured facilely on a piece of gold-deposited screen-printed electrode,which was docked onto a palm-sized detector with remote directives from a mobile APP of Bluetooth handshaking and digital display.Under optimal conditions,the target CAP could be determined in a range from 1 nmol/L to 5μmol/L with a detection limit of 0.25 nmol/L.Further tests on emulate samples demonstrated the miniaturized device could handle the food-screening scenarios with accuracy,convenience and quick response.
