In the process of nickel production by diaphragm electrolysis, the quality of the product has been tremendously affected by the content of zinc in the nickel electrolyte. Removing zinc from nickel electrolyte by ion-e...In the process of nickel production by diaphragm electrolysis, the quality of the product has been tremendously affected by the content of zinc in the nickel electrolyte. Removing zinc from nickel electrolyte by ion-exchange is studied in the paper. Resin D201 is selected as the resin for zinc removing. Effects of the operative parameters, such as temperature, pH value and the contact time on zinc adsorption are observed and the desorption feature of the zinc-loaded resin is inspected. The results show that macroporous anion-exchange resin D201 has excellent adsorption and desorption properties. Its breakthrough capacity and saturation capacity in zinc adsorption reach 0.81 g/L of zinc and 1.16 g/L of zinc respectively, when the operative temperature is 60 °C and the contact time is only 5 min. In addition, compared with gel type IER 201 × 7 used industrially nowadays, this resin has better wearability and greater intensity.展开更多
The goethite residue generated from zinc hydrometallurgy is classified as hazardous solid waste,produced in large quantities,and results in significant zinc loss.The study was conducted on removing iron from FeSO_(4)-...The goethite residue generated from zinc hydrometallurgy is classified as hazardous solid waste,produced in large quantities,and results in significant zinc loss.The study was conducted on removing iron from FeSO_(4)-ZnSO_(4) solution,employing seed-induced nucleation methods.Analysis of the iron removal rate,residue structure,morphology,and elemental composition involved ICP,XRD,FT-IR,and SEM.The existing state of zinc was investigated by combining step-by-step dissolution using hydrochloric acid.Concurrently,iron removal tests were extended to industrial solutions to assess the influence of seeds and solution pH on zinc loss and residue yield.The results revealed that seed addition increased the iron removal rate by 3%,elevated the residual iron content by 6.39%,and mitigated zinc loss by 29.55%in the simulated solution.Seed-induced nucleation prevented excessive nuclei formation,fostering crystal stable growth and high crystallinity.In addition,the zinc content of surface adsorption and crystal internal embedding in the residue was determined,and the zinc distribution on the surface was dense.In contrast,the total amount of zinc within the crystal was higher.The test results in the industrial solution demonstrated that the introduction of seeds expanded the pH range for goethite formation and growth,and the zinc loss per ton of iron removed was reduced by 50.91 kg(34.12%)and the iron residue reduced by 0.17 t(8.72%).展开更多
Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated wi...Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations.展开更多
As a non-contact ultra-precision machining method,abrasive water jet polishing(AWJP)has signi-ficant application in optical elements processing due to its stable tool influence function(TIF),no subsurface damage and s...As a non-contact ultra-precision machining method,abrasive water jet polishing(AWJP)has signi-ficant application in optical elements processing due to its stable tool influence function(TIF),no subsurface damage and strong adaptability to workpiece shapes.In this study,the effects of jet pressure,nozzle diameter and impinging angle on the distribution of pressure,velocity and wall shear stress in the polishing flow field were systematically analyzed by computational fluid dynamics(CFD)simulation.Based on the Box-Behnken experimental design,a response surface regression model was constructed to investigate the influence mech-anism of process parameters on material removal rate(MRR)and surface roughness(Ra)of fused silica.And experimental results showed that increasing jet pressure and nozzle diameter significantly improved MRR,consistent with shear stress distribution revealed by CFD simulations.However,increasing jet pressure and impinging angle caused higher Ra values,which was unfavorable for surface quality improvement.Genetic algorithm(GA)was used for multi-objective optimization to establish Pareto solutions,achieving concurrent optimization of polishing efficiency and surface quality.A parameter combination of 2 MPa jet pressure,0.3 mm nozzle diameter,and 30°impinging angle achieved MRR of 169.05μm^(3)/s and Ra of 0.50 nm.Exper-imental verification showed prediction errors of 4.4%(MRR)and 3.8%(Ra),confirming the model’s reliabil-ity.This parameter optimization system provides theoretical basis and technical support for ultra-precision polishing of complex curved optical components.展开更多
This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal me...This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal method,demonstrating a significant improvement in photocatalytic NO removal under visible light irradiation.For high-flux simulated flue gas,the composite with 10%SnS_(2)(denoted as SNCN-10)showed exceptional NO removal efficiency,reaching up to 66.8%,along with excellent reusability over five consecutive cycles.Detailed band structure and density of states(DOS)calculations confirmed the formation of a characteristic heterojunction.Spin-trapping ESR spectroscopy identified·O_(2)^(-)−as the key reactive species driving NO oxidation.Additionally,in situ DRIFT spectroscopy revealed that SNCN-10 facilitated the conversion of NO to nitrate through intermediate species,including bridging nitrite and cis-nitrite(N_(2)O_(2)^(2-)).Kinetic studies further indicated that NO oxidation followed the Langmuir-Hinshelwood(L-H)mechanism.Based on density functional theory(DFT)calculations of free energy changes,a comprehensive reaction pathway for NO oxidation was proposed.These findings provide valuable insights for the development of efficient photocatalytic strategies for NO removal.展开更多
Copper is a strategic metal that plays an important role in many industries.In copper metallurgy,electrolytic refining is essential to obtain high-purity copper.However,during the electrolytic refining process,impurit...Copper is a strategic metal that plays an important role in many industries.In copper metallurgy,electrolytic refining is essential to obtain high-purity copper.However,during the electrolytic refining process,impurities such as arsenic are introduced into the electrolyte,which significantly affect the subsequent production and quality of copper products.This paper first discusses the sources,forms,and transformation pathways of arsenic in copper electrolyte during the electrolytic process,then reviews various arsenic removal technologies in detail,including electrowinning,adsorption,solvent extraction,ion exchange,membrane filtration,and precipitation.Particular emphasis is placed on electrowinning,which is the most widely used and mature among these arsenic removal techniques.The paper evaluates these methods based on arsenic removal efficiency,cost effectiveness,technical maturity,environmental friendliness,and operation simplicity.In addition,the paper explores future trends in copper electrolyte purification,focusing on waste reduction at source,resource utilization,intelligent digitalization,and innovations in materials and processes.This review aims to provide researchers and practitioners with a comprehensive and in-depth reference on arsenic removal methods in copper electrolytes.展开更多
Removing copper from nickel electrolysis anode solution has been a major keypoint in the nickel metallurgy industry.In this study,we proposed a novel process flow to promote removing copper from nickel electrolysis an...Removing copper from nickel electrolysis anode solution has been a major keypoint in the nickel metallurgy industry.In this study,we proposed a novel process flow to promote removing copper from nickel electrolysis anode solution.A simulated nickel anode solution was designed,and static and dynamic adsorption experiments were conducted to determine the best of solution pH,adsorption time and temperature,resin dosage and particle size,and stirring speed.The optimal conditions were explored for copper removal from nickel electrolysis anode solution.Based on the optimal experimental conditions and the relevant experimental data,a novel process for copper removal from nickel electrolysis anodes was designed and verified.This novel process of copper removal from nickel electrolysis anodes was confirmed with nickel anolyte solution with nickel 50−60 g/L and copper 0.5 g/L.After finishing the novel process of copper removal,the nickel in the purified nickel anolyte became undetectable and copper concentration was 3 mg/L,the novel process of resin adsorption to remove copper from nickel anode solution through static and dynamic adsorptions has an efficacious copper removal.It is a beneficial supplement to traditional methods.展开更多
Arsenic-contained acid polymetallic solutions(AAPS)are produced from the H2SO4 leaching of dust generated during nonferrous metals pyrometallurgy such as copper,lead,and zinc.It is difficult to selectively remove As a...Arsenic-contained acid polymetallic solutions(AAPS)are produced from the H2SO4 leaching of dust generated during nonferrous metals pyrometallurgy such as copper,lead,and zinc.It is difficult to selectively remove As and efficiently recover valuable metals simultaneously.In this study,arsenic was removed from an acid polymetallic solution containing As,Cd,and Zn via scorodite formation using a hydrothermal method.First,a thermodynamic analysis of the Cd^(2+)-Zn^(2+)-Fe^(3+)-AsO_(4)^(3−)-SO_(4)^(2−)-H_(2)O system showed that the pH range for selective As removal as FeAsO4 was 1.8−3.9,and a higher pH will result in the precipitation of Cd in the form of Cd_(5)H_(2)(AsO_(4))_(4).Second,the experimental investigations,including neutralization and hydrothermal processes,showed that 88.96%As was selectively removed as scorodite with a flower cluster morphology in a hydrothermal process after adjusting the pH of AAPS to 1.0 via a neutralization process,while the total loss ratios of Cd and Zn were 2.44%and 1.13%,respectively.This study realized selective separation of Zn and Cd from AAPS by controlling the pH to avoid their loss into scorodite.展开更多
A pre-reduction sintering process with flue gas recirculation(PSP_(fsg)-FGR)was developed to mitigate alkalis harm to the blast furnace and reduce the flue gas emission in the whole ironmaking process.The results indi...A pre-reduction sintering process with flue gas recirculation(PSP_(fsg)-FGR)was developed to mitigate alkalis harm to the blast furnace and reduce the flue gas emission in the whole ironmaking process.The results indicated that the pre-reduction sintering process(PSP)can effectively remove 58.02%of K and 30.68%of Na from raw mixtures and improve yield and tumbler index to 74.40%and 68.69%,respectively.Moreover,PSP was conducive to reducing NO_(x) and SO_(2)emissions and simultaneously increasing CO content in flue gas.Circulating CO-containing flue gas to sintering bed effectively recycled CO and further improved K and Na removal ratio to 74.11%and 32.92%,respectively.Microstructural analysis revealed that the pre-reduced sinter mainly consisted of magnetite,wustite and a small quantity of metallic iron,and very few silicate glass phase was also formed.This process can simultaneously realize alkali metal elements removal as well as flue gas emission reduction from the integrated ironmaking process.展开更多
A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to ...A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to bad and complex environmental conditions.The bounding-box of the logo is extracted by a thershloding approach.Experimental results show that 93.58% location accuracy is achieved with 1100 images under various environmental conditions,indicating that the proposed method is effective and suitable for the location of vehicle logo in practical applications.展开更多
Traditional Chinese medicines(TCMs)are great treasures in pharmacological history with records of more than 3000 years.From ancient times to the present,TCMs of clearing heat,eliminating dampness,unblocking collateral...Traditional Chinese medicines(TCMs)are great treasures in pharmacological history with records of more than 3000 years.From ancient times to the present,TCMs of clearing heat,eliminating dampness,unblocking collaterals and removing toxins have been used in clinic to treat many infectious diseases and noninfectious chronic diseases,whose pathogenesis may involve inflammation induced by different causes.展开更多
Cotton plants are not only the global crops integrating fiber,oil and protein(Hu et al.2020;Xiao et al.2017),but also the medicinal plants with potent application values,which were well described in the most complete ...Cotton plants are not only the global crops integrating fiber,oil and protein(Hu et al.2020;Xiao et al.2017),but also the medicinal plants with potent application values,which were well described in the most complete and comprehensive medical book such as Compendium of Materia Medica and Chinese Materia Medica.Cot-ton extract has various activities such as stopping bleed-ing,relieving pain,removing phlegm,and curing chronic bronchitis.Different types of metabolites or defense compounds are produced in cotton plants.展开更多
ailure of regeneration in injured axons accounts for permanent functional deficits after CNS injury.Thus,there has been a tremendous need to understand the mechanisms underlying regeneration failure.Previously,a predo...ailure of regeneration in injured axons accounts for permanent functional deficits after CNS injury.Thus,there has been a tremendous need to understand the mechanisms underlying regeneration failure.Previously,a predominant hypothesis held that extrinsic inhibitory factors in the adult CNS environment prevent injured axons from re-growth.However,blocking these inhibitory activities genetically led to little or no axon regeneration in vivo,suggesting that removing inhibitory activities alone is展开更多
By analyzing the abrasive theory of concrete diamond sawblade, the proposal that the diamond should be selected by its function in cutting concrete is presented. The part of the big grit diamonds cut rock, and the par...By analyzing the abrasive theory of concrete diamond sawblade, the proposal that the diamond should be selected by its function in cutting concrete is presented. The part of the big grit diamonds cut rock, and the part of the small grit diamonds improve the wearability of the matrix. The contrast tests are done with different shapes of sawbaldes in split segment, slant "U" slot segment, sandwich segment, turbo segment and three-slot segment. The special shapes of sawblades can improve the effect of cooling and the removing ability of the rock powder. The data of tests show that the efficiency of cutting and the life of sawblades are improved by designing the diamond prescription and using the especial geometry of segment.展开更多
Background:The photosynthetic parameters of cotton plants may be modified by the timing of film removal during their growing period.This study was undertaken during 2015-2017 in Xinjiang,China,to determine to what ext...Background:The photosynthetic parameters of cotton plants may be modified by the timing of film removal during their growing period.This study was undertaken during 2015-2017 in Xinjiang,China,to determine to what extent the film mulching removal time,1 and 10 days before the first irrigation and 1 day before the second irrigation after seedling emergence,influenced cotton's photosynthetic characteristics.The control group(CK)was film-mulched throughout the growth stages.Results:The results suggested the following:(1)Removing mulching-film within 50 days since seedling emergence had adverse effects on soil temperature and moisture.(2)Film-removal before the first or second irrigation after emergence improved the net photosynthetic rate in cotton's later flowering stage and its transpiration rate in mid and later flowed ng stages while enhancing the actual electron transport rate(ETR)and maximum electron transfer rate(ETRmax)between cotton photosystems I and II.(3)Film-removal treatment also increased cotton plants'toleranee to high irradiation after emergence,the trend was more pronounced in the early flowering stage in wetter years.(4)Leaf area index(LAI)of cotton was reduced in the film-removal treatment for which the least accumulation of dry matter occurred in a drought year(i.e.,2015).(5)Film removal caused a yield decrease in the dry year(2015),and the earlier the film was removed,the more seriously the yield decreased.Removing mulching film before the second irrigation could increase the yield of XLZ42 in the rainy year(2016)and the normal rainfall year(2017).Early film removal can in crease the yield of XLZ45 in the rainy year(2016).Conclusions:Collectively,our stud/s experimental results indicate that applying mulch film removal at an appropriate,targeted time after seedling emerge nee had no adverse effects on soil moisture and temperature,and improved the photosy nthetic performance of cotton,thus in creased cotton yield and fiber quality,but no significant difference was reached.展开更多
Paint removal from steel structure is executed for shipyards of marine and offshore engineering.Due to environmental unfriendliness and unhealthy drawbacks of sand blasting technique, laser ablation technique is propo...Paint removal from steel structure is executed for shipyards of marine and offshore engineering.Due to environmental unfriendliness and unhealthy drawbacks of sand blasting technique, laser ablation technique is proposed as a substituting method.By absorbing high energy of the 1064 nm pulsed laser, the paint is vaporized quickly.The ablated debris is then collected by using a suction pump.Initial metal surface of the steel is exposed when laser beam irradiates perpendicularly and scans over it.The cleaned surface fulfills the requirements of surface preparation standards ISO 8501 of SA2.The adhesion is further characterized with pull-off test after carrying out painting with Jotamastic 87 aluminum paint.The repainting can be embedded onto the laser cleaned surface to bond much more tightly.The excellent adhesion strength of 20 MPa between repainted coating and the substrate is achieved, which is higher than what is required by shipyards applications.展开更多
文摘In the process of nickel production by diaphragm electrolysis, the quality of the product has been tremendously affected by the content of zinc in the nickel electrolyte. Removing zinc from nickel electrolyte by ion-exchange is studied in the paper. Resin D201 is selected as the resin for zinc removing. Effects of the operative parameters, such as temperature, pH value and the contact time on zinc adsorption are observed and the desorption feature of the zinc-loaded resin is inspected. The results show that macroporous anion-exchange resin D201 has excellent adsorption and desorption properties. Its breakthrough capacity and saturation capacity in zinc adsorption reach 0.81 g/L of zinc and 1.16 g/L of zinc respectively, when the operative temperature is 60 °C and the contact time is only 5 min. In addition, compared with gel type IER 201 × 7 used industrially nowadays, this resin has better wearability and greater intensity.
基金Project(2018YFC1900403) supported by the National Key Research and Development Program of ChinaProject(CX20210197) supported by the Postgraduate Scientific Research Innovation Project of Hunan Province,China+1 种基金Project(202206370103) supported by the China Scholarship CouncilProject(2021zzts0115) supported by the Fundamental Research Funds for the Central Universities,China。
文摘The goethite residue generated from zinc hydrometallurgy is classified as hazardous solid waste,produced in large quantities,and results in significant zinc loss.The study was conducted on removing iron from FeSO_(4)-ZnSO_(4) solution,employing seed-induced nucleation methods.Analysis of the iron removal rate,residue structure,morphology,and elemental composition involved ICP,XRD,FT-IR,and SEM.The existing state of zinc was investigated by combining step-by-step dissolution using hydrochloric acid.Concurrently,iron removal tests were extended to industrial solutions to assess the influence of seeds and solution pH on zinc loss and residue yield.The results revealed that seed addition increased the iron removal rate by 3%,elevated the residual iron content by 6.39%,and mitigated zinc loss by 29.55%in the simulated solution.Seed-induced nucleation prevented excessive nuclei formation,fostering crystal stable growth and high crystallinity.In addition,the zinc content of surface adsorption and crystal internal embedding in the residue was determined,and the zinc distribution on the surface was dense.In contrast,the total amount of zinc within the crystal was higher.The test results in the industrial solution demonstrated that the introduction of seeds expanded the pH range for goethite formation and growth,and the zinc loss per ton of iron removed was reduced by 50.91 kg(34.12%)and the iron residue reduced by 0.17 t(8.72%).
基金supported by the National Natural Science Foundation of China(22278066,21776039)the National Key R&D Program of China(2023YFB4103001)The Fundamental Research Funds for the Central Universities(DUT2021TB03).
文摘Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations.
文摘As a non-contact ultra-precision machining method,abrasive water jet polishing(AWJP)has signi-ficant application in optical elements processing due to its stable tool influence function(TIF),no subsurface damage and strong adaptability to workpiece shapes.In this study,the effects of jet pressure,nozzle diameter and impinging angle on the distribution of pressure,velocity and wall shear stress in the polishing flow field were systematically analyzed by computational fluid dynamics(CFD)simulation.Based on the Box-Behnken experimental design,a response surface regression model was constructed to investigate the influence mech-anism of process parameters on material removal rate(MRR)and surface roughness(Ra)of fused silica.And experimental results showed that increasing jet pressure and nozzle diameter significantly improved MRR,consistent with shear stress distribution revealed by CFD simulations.However,increasing jet pressure and impinging angle caused higher Ra values,which was unfavorable for surface quality improvement.Genetic algorithm(GA)was used for multi-objective optimization to establish Pareto solutions,achieving concurrent optimization of polishing efficiency and surface quality.A parameter combination of 2 MPa jet pressure,0.3 mm nozzle diameter,and 30°impinging angle achieved MRR of 169.05μm^(3)/s and Ra of 0.50 nm.Exper-imental verification showed prediction errors of 4.4%(MRR)and 3.8%(Ra),confirming the model’s reliabil-ity.This parameter optimization system provides theoretical basis and technical support for ultra-precision polishing of complex curved optical components.
基金The project was supported by Natural Science Foundation of Shandong Province(ZR2021MB104)National Natural Science Foundation of China(22078174).
文摘This study aims to enhance the photocatalytic performance of 2D/2D heterojunctions for NO removal from marine vessel effluents.SnS_(2)/g-C_(3)N_(4) composites were successfully constructed via a facile solvothermal method,demonstrating a significant improvement in photocatalytic NO removal under visible light irradiation.For high-flux simulated flue gas,the composite with 10%SnS_(2)(denoted as SNCN-10)showed exceptional NO removal efficiency,reaching up to 66.8%,along with excellent reusability over five consecutive cycles.Detailed band structure and density of states(DOS)calculations confirmed the formation of a characteristic heterojunction.Spin-trapping ESR spectroscopy identified·O_(2)^(-)−as the key reactive species driving NO oxidation.Additionally,in situ DRIFT spectroscopy revealed that SNCN-10 facilitated the conversion of NO to nitrate through intermediate species,including bridging nitrite and cis-nitrite(N_(2)O_(2)^(2-)).Kinetic studies further indicated that NO oxidation followed the Langmuir-Hinshelwood(L-H)mechanism.Based on density functional theory(DFT)calculations of free energy changes,a comprehensive reaction pathway for NO oxidation was proposed.These findings provide valuable insights for the development of efficient photocatalytic strategies for NO removal.
基金Project(52174385)supported by the National Natural Science Foundation of ChinaProjects(2023YFC3904003,2023YFC3904004,2023YFC390400501)supported by the National Key R&D Program of China。
文摘Copper is a strategic metal that plays an important role in many industries.In copper metallurgy,electrolytic refining is essential to obtain high-purity copper.However,during the electrolytic refining process,impurities such as arsenic are introduced into the electrolyte,which significantly affect the subsequent production and quality of copper products.This paper first discusses the sources,forms,and transformation pathways of arsenic in copper electrolyte during the electrolytic process,then reviews various arsenic removal technologies in detail,including electrowinning,adsorption,solvent extraction,ion exchange,membrane filtration,and precipitation.Particular emphasis is placed on electrowinning,which is the most widely used and mature among these arsenic removal techniques.The paper evaluates these methods based on arsenic removal efficiency,cost effectiveness,technical maturity,environmental friendliness,and operation simplicity.In addition,the paper explores future trends in copper electrolyte purification,focusing on waste reduction at source,resource utilization,intelligent digitalization,and innovations in materials and processes.This review aims to provide researchers and practitioners with a comprehensive and in-depth reference on arsenic removal methods in copper electrolytes.
基金Project(2019yff0216502)supported by the National Key Research&Development Plan of Ministry of Science and Technology of ChinaProject(2021SK1020-4)supported by the Major Science and Technological Innovation Project of Hunan Province,China。
文摘Removing copper from nickel electrolysis anode solution has been a major keypoint in the nickel metallurgy industry.In this study,we proposed a novel process flow to promote removing copper from nickel electrolysis anode solution.A simulated nickel anode solution was designed,and static and dynamic adsorption experiments were conducted to determine the best of solution pH,adsorption time and temperature,resin dosage and particle size,and stirring speed.The optimal conditions were explored for copper removal from nickel electrolysis anode solution.Based on the optimal experimental conditions and the relevant experimental data,a novel process for copper removal from nickel electrolysis anodes was designed and verified.This novel process of copper removal from nickel electrolysis anodes was confirmed with nickel anolyte solution with nickel 50−60 g/L and copper 0.5 g/L.After finishing the novel process of copper removal,the nickel in the purified nickel anolyte became undetectable and copper concentration was 3 mg/L,the novel process of resin adsorption to remove copper from nickel anode solution through static and dynamic adsorptions has an efficacious copper removal.It is a beneficial supplement to traditional methods.
基金Project(23B05465) supported by the Scientific Research Fund of Hunan Provincial Education Department,China。
文摘Arsenic-contained acid polymetallic solutions(AAPS)are produced from the H2SO4 leaching of dust generated during nonferrous metals pyrometallurgy such as copper,lead,and zinc.It is difficult to selectively remove As and efficiently recover valuable metals simultaneously.In this study,arsenic was removed from an acid polymetallic solution containing As,Cd,and Zn via scorodite formation using a hydrothermal method.First,a thermodynamic analysis of the Cd^(2+)-Zn^(2+)-Fe^(3+)-AsO_(4)^(3−)-SO_(4)^(2−)-H_(2)O system showed that the pH range for selective As removal as FeAsO4 was 1.8−3.9,and a higher pH will result in the precipitation of Cd in the form of Cd_(5)H_(2)(AsO_(4))_(4).Second,the experimental investigations,including neutralization and hydrothermal processes,showed that 88.96%As was selectively removed as scorodite with a flower cluster morphology in a hydrothermal process after adjusting the pH of AAPS to 1.0 via a neutralization process,while the total loss ratios of Cd and Zn were 2.44%and 1.13%,respectively.This study realized selective separation of Zn and Cd from AAPS by controlling the pH to avoid their loss into scorodite.
基金Project(52274290)supported by the National Natural Science Foundation of ChinaProject(72088101)supported by the Basic Science Center Project for National Natural Science Foundation of China。
文摘A pre-reduction sintering process with flue gas recirculation(PSP_(fsg)-FGR)was developed to mitigate alkalis harm to the blast furnace and reduce the flue gas emission in the whole ironmaking process.The results indicated that the pre-reduction sintering process(PSP)can effectively remove 58.02%of K and 30.68%of Na from raw mixtures and improve yield and tumbler index to 74.40%and 68.69%,respectively.Moreover,PSP was conducive to reducing NO_(x) and SO_(2)emissions and simultaneously increasing CO content in flue gas.Circulating CO-containing flue gas to sintering bed effectively recycled CO and further improved K and Na removal ratio to 74.11%and 32.92%,respectively.Microstructural analysis revealed that the pre-reduced sinter mainly consisted of magnetite,wustite and a small quantity of metallic iron,and very few silicate glass phase was also formed.This process can simultaneously realize alkali metal elements removal as well as flue gas emission reduction from the integrated ironmaking process.
文摘A patch-based method for detecting vehicle logos using prior knowledge is proposed.By representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to bad and complex environmental conditions.The bounding-box of the logo is extracted by a thershloding approach.Experimental results show that 93.58% location accuracy is achieved with 1100 images under various environmental conditions,indicating that the proposed method is effective and suitable for the location of vehicle logo in practical applications.
文摘Traditional Chinese medicines(TCMs)are great treasures in pharmacological history with records of more than 3000 years.From ancient times to the present,TCMs of clearing heat,eliminating dampness,unblocking collaterals and removing toxins have been used in clinic to treat many infectious diseases and noninfectious chronic diseases,whose pathogenesis may involve inflammation induced by different causes.
基金This research was supported by grants from the National Natural Science Foundation of China(31788103)the Chinese Academy of Sciences(XDB27020207).
文摘Cotton plants are not only the global crops integrating fiber,oil and protein(Hu et al.2020;Xiao et al.2017),but also the medicinal plants with potent application values,which were well described in the most complete and comprehensive medical book such as Compendium of Materia Medica and Chinese Materia Medica.Cot-ton extract has various activities such as stopping bleed-ing,relieving pain,removing phlegm,and curing chronic bronchitis.Different types of metabolites or defense compounds are produced in cotton plants.
文摘ailure of regeneration in injured axons accounts for permanent functional deficits after CNS injury.Thus,there has been a tremendous need to understand the mechanisms underlying regeneration failure.Previously,a predominant hypothesis held that extrinsic inhibitory factors in the adult CNS environment prevent injured axons from re-growth.However,blocking these inhibitory activities genetically led to little or no axon regeneration in vivo,suggesting that removing inhibitory activities alone is
文摘By analyzing the abrasive theory of concrete diamond sawblade, the proposal that the diamond should be selected by its function in cutting concrete is presented. The part of the big grit diamonds cut rock, and the part of the small grit diamonds improve the wearability of the matrix. The contrast tests are done with different shapes of sawbaldes in split segment, slant "U" slot segment, sandwich segment, turbo segment and three-slot segment. The special shapes of sawblades can improve the effect of cooling and the removing ability of the rock powder. The data of tests show that the efficiency of cutting and the life of sawblades are improved by designing the diamond prescription and using the especial geometry of segment.
基金the special fund for scientific research into non-profit industries(agriculture,grant no.201503120).
文摘Background:The photosynthetic parameters of cotton plants may be modified by the timing of film removal during their growing period.This study was undertaken during 2015-2017 in Xinjiang,China,to determine to what extent the film mulching removal time,1 and 10 days before the first irrigation and 1 day before the second irrigation after seedling emergence,influenced cotton's photosynthetic characteristics.The control group(CK)was film-mulched throughout the growth stages.Results:The results suggested the following:(1)Removing mulching-film within 50 days since seedling emergence had adverse effects on soil temperature and moisture.(2)Film-removal before the first or second irrigation after emergence improved the net photosynthetic rate in cotton's later flowering stage and its transpiration rate in mid and later flowed ng stages while enhancing the actual electron transport rate(ETR)and maximum electron transfer rate(ETRmax)between cotton photosystems I and II.(3)Film-removal treatment also increased cotton plants'toleranee to high irradiation after emergence,the trend was more pronounced in the early flowering stage in wetter years.(4)Leaf area index(LAI)of cotton was reduced in the film-removal treatment for which the least accumulation of dry matter occurred in a drought year(i.e.,2015).(5)Film removal caused a yield decrease in the dry year(2015),and the earlier the film was removed,the more seriously the yield decreased.Removing mulching film before the second irrigation could increase the yield of XLZ42 in the rainy year(2016)and the normal rainfall year(2017).Early film removal can in crease the yield of XLZ45 in the rainy year(2016).Conclusions:Collectively,our stud/s experimental results indicate that applying mulch film removal at an appropriate,targeted time after seedling emerge nee had no adverse effects on soil moisture and temperature,and improved the photosy nthetic performance of cotton,thus in creased cotton yield and fiber quality,but no significant difference was reached.
基金supported by the National Natural Science Foundation of China (U1609209)National Natural Science Foundation of China (61605162)+2 种基金NSFC-Liaoning Province united foundation (U1608259)National Natural Science Foundation of China (51501219)the financial support from the China Scholarship Council
文摘Paint removal from steel structure is executed for shipyards of marine and offshore engineering.Due to environmental unfriendliness and unhealthy drawbacks of sand blasting technique, laser ablation technique is proposed as a substituting method.By absorbing high energy of the 1064 nm pulsed laser, the paint is vaporized quickly.The ablated debris is then collected by using a suction pump.Initial metal surface of the steel is exposed when laser beam irradiates perpendicularly and scans over it.The cleaned surface fulfills the requirements of surface preparation standards ISO 8501 of SA2.The adhesion is further characterized with pull-off test after carrying out painting with Jotamastic 87 aluminum paint.The repainting can be embedded onto the laser cleaned surface to bond much more tightly.The excellent adhesion strength of 20 MPa between repainted coating and the substrate is achieved, which is higher than what is required by shipyards applications.
