The influences of category and density of reagents, temperature and the value of pH in the solution of stripping the nickel coating on NdFeB permanent magnet on the stripping result were studied systematically.The pra...The influences of category and density of reagents, temperature and the value of pH in the solution of stripping the nickel coating on NdFeB permanent magnet on the stripping result were studied systematically.The practical formular contains mainly the oxidant m-O2NC6H4SO3Na, the complex reagent ( NaOOCCH2 ) 2N( CH2 ) 2N( CH2COOH)2,the reagent of retarding corrosion KF and the calatyze RL-3 was obtained.展开更多
The development trend of coated and plated technology for continuous strip steels,which include hot dip plating,electroplating,organic coating and vacuum plating technology,were summarized.
Vapor deposited coatings onto strip steel are a promising alternative as functional layers for corrosion protection or high abrasion resistance.Conventional coating systems have some limits regarding environmental com...Vapor deposited coatings onto strip steel are a promising alternative as functional layers for corrosion protection or high abrasion resistance.Conventional coating systems have some limits regarding environmental compatibility,the range of coating materials and application properties. Physical vapor deposition(PVD) is an environment-friendly technology and enables nearly unlimited material and process variety.Electron beam high-rate evaporation with deposition rates up to some micrometers per second is the most productive PVD technology for low cost coating.The combination of evaporation with powerful plasma is an efficient way to improve the layer properties.The developed plasma sources can be used for special plasma enhanced chemical vapor deposition(PECVD) processes too. The paper gives an overview about the latest developments in these technologies.Furthermore,the paper explains some examples of new layer stacks onto steel strips.While enhanced corrosion protection can be obtained by magnesium,aluminium or copper containing coatings other functional surface properties come more and more in the focus of interest.For instance,decorative gold colored layers,transparent scratch resistant layers,hard coatings and photo catalytic layers were deposited on running steel strips.Functional layers and layer systems for energy saving and sun energy absorption by solar thermal effects and photo voltaics are under development.The coatings are prepared under the conditions of very high deposition rates using our in-line vacuum coater for metallic strips and sheets with the name MAXI.The influence of the process and plasma parameters on the layer properties were investigated and will be demonstrated for some applications.展开更多
A rapid and sensitive 1.5 order adsorptive stripping voltammetric method fordetendnation of trace mitoxantrone (MXT) is described. The accumulation behavior of MXT on amercury film ndcroelectrode was studied and the p...A rapid and sensitive 1.5 order adsorptive stripping voltammetric method fordetendnation of trace mitoxantrone (MXT) is described. The accumulation behavior of MXT on amercury film ndcroelectrode was studied and the possibility of carrying out 1.5 order differentialadsorptive stripping analysis using mercury-coated carbon fiber ndcroelectrode was demonstrated.Optimal conditions for 1.5 order differential voltammetry monitoring are described. The strippingpeak current is linearly proportional to the concentration of MAT in the range of 1.0×10-6 mol/L 1.0×10-9 and detection licit is 1.5×10-10 mol/L. The relative standard deviation (RSD) is 3.0% at5.0×10-8 (n=8). MXT can be detendned directly in biological samples at physiological levelswithout any separation procedure.展开更多
The principle, formula and determination of internal stresses of metal multilayer composite coatings by means of the bending strip method were studied. Using this method, internal stresses of ion-plated metal multilay...The principle, formula and determination of internal stresses of metal multilayer composite coatings by means of the bending strip method were studied. Using this method, internal stresses of ion-plated metal multilayer composite coatings and thick monolayer coating of aluminium bronze, stainless steel and nickel-iron alloy were determined. The reason of decrement in internal stresses of multilayer composite coatings was discussed.展开更多
The production of environmental friendly emulsion paint is of great significance. Vacuum steam stripping of methyl isobutyl ketone （MIBK） and methyl ethyl ketone （MEK） from cathodic electrophoretic emulsion was st...The production of environmental friendly emulsion paint is of great significance. Vacuum steam stripping of methyl isobutyl ketone （MIBK） and methyl ethyl ketone （MEK） from cathodic electrophoretic emulsion was studied. The effects of mass ratio of vapor to feed （V/F）, vacuum degree and feed temperature on removal rate of MIBK and MEK, emulsion size and solid volume fraction of the emulsion were investigated, and the removal of MIBK and MEK from cathodic electrophoretic emulsion by vacuum desorption was also studied. The results show that removal rates of both MIBK and MEK increase with the increase of V/F, vacuum degree and feed temperature. Removal rates of MIBK and MEK are 98.3% and 93.6%, respectively, at the operating condition V/F of 0.7, feed temperature of 27℃ and vacuum degree of 90 kPa. The emulsion size of cathodic electrophoretic emulsion increases slightly with feed temperature when temperature is below 42 ℃, and increases rapidly with feed temperature when temperature is above 42℃. Solid volume fraction increases by 10% as vacuum degree increases from 0 to 90 kPa at V/F of 0.7 and feed temperature of 27 ℃. Compared with vacuum desorption, vacuum steam stripping can get a higher removal rate of MIBK and MEK under the same feed flow, vacuum degree and feed temperature.展开更多
The outstanding tribological performance of transition metal dichalcogenides(TMDs)is attributed to their unique sandwich microstructure and low interlayer shear stress.This advantageous structure allows TMDs to demons...The outstanding tribological performance of transition metal dichalcogenides(TMDs)is attributed to their unique sandwich microstructure and low interlayer shear stress.This advantageous structure allows TMDs to demonstrate exceptional friction reduction properties.Furthermore,the incorporation of TMDs and amorphous carbon(a-C)in multi-layer structures shows excellent potential for further enhancing tribological and anti-oxidation properties.Amorphous carbon,known for its high ductility,chemical inertness,and excellent wear resistance,significantly contributes to the overall performance of these multi-layer coatings.To gain an in-depth understanding of the tribological mechanism and evolution of TMDs’multi-layer coatings,a dual in-situ analysis was carried out using a tribometer equipped with a 3D laser microscope and a Raman spectrometer.This innovative approach allowed for a comprehensive evolution of the tribological,topographical,and tribochemical characteristics of both single-layer WS_(2)and multi-layer WS_(2)/C coatings in real time.The findings from the dual in-situ tribotest revealed distinct failure characteristics between the single-layer WS_(2)coating and the multi-layer WS_(2)/C coating.The single-layer WS_(2)coating predominantly experienced failure due to mechanical removal,whereas a combination of mechanical removal and tribochemistry primarily influenced the failure of the multi-layer WS_(2)/C coating.The tribological evolution process of these two coatings can be classified into four stages on the basis of their tribological behavior:the running-in stage,stable friction stage,re-deposition stage,and lubrication failure stage.Each stage represents a distinct phase in the tribological behavior of the coatings and contributes to our understanding of their behavior during sliding.展开更多
Magnesium(Mg)and its alloys have become a hot research topic in various industries owing to the specific physical and chemical properties.However,high corrosion rate is considered the key lifetime-limiting.Plasma elec...Magnesium(Mg)and its alloys have become a hot research topic in various industries owing to the specific physical and chemical properties.However,high corrosion rate is considered the key lifetime-limiting.Plasma electrolytic oxidation(PEO)method is a simple strategy to deposit an oxide layer on the surface of light metals such as magnesium alloys,to control corrosion rate and promote some other properties,depending on their performances.Nevertheless,their features including their micropore size,distribution,and interconnectivity,and microcracks have not been improved to an acceptable level to support long-term performances of the magnesium-based substrates.Studies have introduced micro/nano-enabled approaches to enhance various properties of PEO coatings such as corrosion resistance,tribological properties,self-healing ability,bioactivity,biocompatibility,antibacterial properties,or catalytic performances.These strategies consist of incorporating of micro and nanoparticles into the PEO layers to produce multi-functional surfaces or the formation of multi-layered coatings to cover the defects of PEO coatings.In this perspective,the present paper aims to overview various nano/micro-enabled strategies to promote the properties of PEO coatings on magnesium alloys.The main focus is given to the functional changes that occurred in response to the incorporation of various types of nano/micro-structures into the PEO coatings on magnesium alloys.展开更多
The differential potentiometric stripping analysis (DPSA) with Nafion coated carbon fibre electrode has been studied, and a method to determine lead and cadmium in urine directly has been attempted. The effect of vari...The differential potentiometric stripping analysis (DPSA) with Nafion coated carbon fibre electrode has been studied, and a method to determine lead and cadmium in urine directly has been attempted. The effect of various experimental parameters on the DPSA response is discussed. The experimental conditions include 0.2M sodium perchlorate, deposition potential of-1.0 or -1.1 V and using 20 ppm mercuric ion as oxidizing agent. The response of the signal is in linear relation with the concentrations of lead and cadmium respectively up to 0.5 ppm. The electrode coated with Nafion film alleviates the interference from organics in urine samples.展开更多
文摘The influences of category and density of reagents, temperature and the value of pH in the solution of stripping the nickel coating on NdFeB permanent magnet on the stripping result were studied systematically.The practical formular contains mainly the oxidant m-O2NC6H4SO3Na, the complex reagent ( NaOOCCH2 ) 2N( CH2 ) 2N( CH2COOH)2,the reagent of retarding corrosion KF and the calatyze RL-3 was obtained.
文摘The development trend of coated and plated technology for continuous strip steels,which include hot dip plating,electroplating,organic coating and vacuum plating technology,were summarized.
文摘Vapor deposited coatings onto strip steel are a promising alternative as functional layers for corrosion protection or high abrasion resistance.Conventional coating systems have some limits regarding environmental compatibility,the range of coating materials and application properties. Physical vapor deposition(PVD) is an environment-friendly technology and enables nearly unlimited material and process variety.Electron beam high-rate evaporation with deposition rates up to some micrometers per second is the most productive PVD technology for low cost coating.The combination of evaporation with powerful plasma is an efficient way to improve the layer properties.The developed plasma sources can be used for special plasma enhanced chemical vapor deposition(PECVD) processes too. The paper gives an overview about the latest developments in these technologies.Furthermore,the paper explains some examples of new layer stacks onto steel strips.While enhanced corrosion protection can be obtained by magnesium,aluminium or copper containing coatings other functional surface properties come more and more in the focus of interest.For instance,decorative gold colored layers,transparent scratch resistant layers,hard coatings and photo catalytic layers were deposited on running steel strips.Functional layers and layer systems for energy saving and sun energy absorption by solar thermal effects and photo voltaics are under development.The coatings are prepared under the conditions of very high deposition rates using our in-line vacuum coater for metallic strips and sheets with the name MAXI.The influence of the process and plasma parameters on the layer properties were investigated and will be demonstrated for some applications.
文摘A rapid and sensitive 1.5 order adsorptive stripping voltammetric method fordetendnation of trace mitoxantrone (MXT) is described. The accumulation behavior of MXT on amercury film ndcroelectrode was studied and the possibility of carrying out 1.5 order differentialadsorptive stripping analysis using mercury-coated carbon fiber ndcroelectrode was demonstrated.Optimal conditions for 1.5 order differential voltammetry monitoring are described. The strippingpeak current is linearly proportional to the concentration of MAT in the range of 1.0×10-6 mol/L 1.0×10-9 and detection licit is 1.5×10-10 mol/L. The relative standard deviation (RSD) is 3.0% at5.0×10-8 (n=8). MXT can be detendned directly in biological samples at physiological levelswithout any separation procedure.
文摘The principle, formula and determination of internal stresses of metal multilayer composite coatings by means of the bending strip method were studied. Using this method, internal stresses of ion-plated metal multilayer composite coatings and thick monolayer coating of aluminium bronze, stainless steel and nickel-iron alloy were determined. The reason of decrement in internal stresses of multilayer composite coatings was discussed.
基金Project(21176264)supported by the National Natural Science Foundation of ChinaProject(ZL110414)supported by the Undergraduate Free Exploration Innovation Foundation of Central South University,China
文摘The production of environmental friendly emulsion paint is of great significance. Vacuum steam stripping of methyl isobutyl ketone （MIBK） and methyl ethyl ketone （MEK） from cathodic electrophoretic emulsion was studied. The effects of mass ratio of vapor to feed （V/F）, vacuum degree and feed temperature on removal rate of MIBK and MEK, emulsion size and solid volume fraction of the emulsion were investigated, and the removal of MIBK and MEK from cathodic electrophoretic emulsion by vacuum desorption was also studied. The results show that removal rates of both MIBK and MEK increase with the increase of V/F, vacuum degree and feed temperature. Removal rates of MIBK and MEK are 98.3% and 93.6%, respectively, at the operating condition V/F of 0.7, feed temperature of 27℃ and vacuum degree of 90 kPa. The emulsion size of cathodic electrophoretic emulsion increases slightly with feed temperature when temperature is below 42 ℃, and increases rapidly with feed temperature when temperature is above 42℃. Solid volume fraction increases by 10% as vacuum degree increases from 0 to 90 kPa at V/F of 0.7 and feed temperature of 27 ℃. Compared with vacuum desorption, vacuum steam stripping can get a higher removal rate of MIBK and MEK under the same feed flow, vacuum degree and feed temperature.
基金the fund of LICP Cooperation Foundation for Young Scholars(GrantNo.HZJJ22-03)the financial support provided by China National Natural Science Foundation(Grant No.52075521)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0470102)Natural Science Foundation of Shandong Province(Grant No.022HWYQ-096)LICP International Cooperative Scholarship,and the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(Grant No.2020R1A2C2004714).
文摘The outstanding tribological performance of transition metal dichalcogenides(TMDs)is attributed to their unique sandwich microstructure and low interlayer shear stress.This advantageous structure allows TMDs to demonstrate exceptional friction reduction properties.Furthermore,the incorporation of TMDs and amorphous carbon(a-C)in multi-layer structures shows excellent potential for further enhancing tribological and anti-oxidation properties.Amorphous carbon,known for its high ductility,chemical inertness,and excellent wear resistance,significantly contributes to the overall performance of these multi-layer coatings.To gain an in-depth understanding of the tribological mechanism and evolution of TMDs’multi-layer coatings,a dual in-situ analysis was carried out using a tribometer equipped with a 3D laser microscope and a Raman spectrometer.This innovative approach allowed for a comprehensive evolution of the tribological,topographical,and tribochemical characteristics of both single-layer WS_(2)and multi-layer WS_(2)/C coatings in real time.The findings from the dual in-situ tribotest revealed distinct failure characteristics between the single-layer WS_(2)coating and the multi-layer WS_(2)/C coating.The single-layer WS_(2)coating predominantly experienced failure due to mechanical removal,whereas a combination of mechanical removal and tribochemistry primarily influenced the failure of the multi-layer WS_(2)/C coating.The tribological evolution process of these two coatings can be classified into four stages on the basis of their tribological behavior:the running-in stage,stable friction stage,re-deposition stage,and lubrication failure stage.Each stage represents a distinct phase in the tribological behavior of the coatings and contributes to our understanding of their behavior during sliding.
文摘Magnesium(Mg)and its alloys have become a hot research topic in various industries owing to the specific physical and chemical properties.However,high corrosion rate is considered the key lifetime-limiting.Plasma electrolytic oxidation(PEO)method is a simple strategy to deposit an oxide layer on the surface of light metals such as magnesium alloys,to control corrosion rate and promote some other properties,depending on their performances.Nevertheless,their features including their micropore size,distribution,and interconnectivity,and microcracks have not been improved to an acceptable level to support long-term performances of the magnesium-based substrates.Studies have introduced micro/nano-enabled approaches to enhance various properties of PEO coatings such as corrosion resistance,tribological properties,self-healing ability,bioactivity,biocompatibility,antibacterial properties,or catalytic performances.These strategies consist of incorporating of micro and nanoparticles into the PEO layers to produce multi-functional surfaces or the formation of multi-layered coatings to cover the defects of PEO coatings.In this perspective,the present paper aims to overview various nano/micro-enabled strategies to promote the properties of PEO coatings on magnesium alloys.The main focus is given to the functional changes that occurred in response to the incorporation of various types of nano/micro-structures into the PEO coatings on magnesium alloys.
基金This project was supported by the National Natural Science Foundation of China
文摘The differential potentiometric stripping analysis (DPSA) with Nafion coated carbon fibre electrode has been studied, and a method to determine lead and cadmium in urine directly has been attempted. The effect of various experimental parameters on the DPSA response is discussed. The experimental conditions include 0.2M sodium perchlorate, deposition potential of-1.0 or -1.1 V and using 20 ppm mercuric ion as oxidizing agent. The response of the signal is in linear relation with the concentrations of lead and cadmium respectively up to 0.5 ppm. The electrode coated with Nafion film alleviates the interference from organics in urine samples.
