The limited charge extraction efficiency and suboptimal energy-level alignment of poly(3,4-ethylenediox ythiophene)polystyrene sulfonate(PEDOT:PSS)as a hole transport layer restrict its performance in solar cell appli...The limited charge extraction efficiency and suboptimal energy-level alignment of poly(3,4-ethylenediox ythiophene)polystyrene sulfonate(PEDOT:PSS)as a hole transport layer restrict its performance in solar cell applications.In this study,we developed effective copper-ion(Cu(Ⅱ))-modified oxyl-terminated melem two-dimensional(2D)nanodisks(Cu(Ⅱ)@OMN)that improved the performance of PEDOT:PSS as a representative hole-transport layer(HTL)in organic and perovskite solar cells.Based on theoretical calculations and experimental data,the interaction between Cu(Ⅱ)@OMN and PEDOT or PSS led to electron redistribution in PEDOT:PSS and the dissociation of PEDOT and PSS,promoting enhanced charge extraction and transfer.In addition,the work function of the Cu(Ⅱ)@OMN-PEDOT:PSS is modified to achieve a more beneficial energy-level alignment,thereby facilitating improved hole transport and inhibited nonradiative recombination.Methylammonium(MA)-based perovskite and organic binary PM6:Y6solar cells achieved power conversion efficiencies(PCEs)of 19.21% and 17.15%,respectively.These PCEs are among the highest reported for MA-based perovskite and binary PM6:Y6 organic solar cells that use 2D nanomaterial-modified PEDOT:PSS,demonstrating the potential of Cu(Ⅱ)@OMN in solar cell applications.展开更多
The adsorption behaviors of copper ions on chalcopyrite surfaces were investigated based on zeta potential measurements, X-ray photoelectron spectroscopy, copper ion adsorption experiments, first-principles calculatio...The adsorption behaviors of copper ions on chalcopyrite surfaces were investigated based on zeta potential measurements, X-ray photoelectron spectroscopy, copper ion adsorption experiments, first-principles calculations, and Hallimond tube cell flotation experiments. The results show that copper ions activate the chalcopyrite as a result of the interactions between copper ions and sulfur on the chalcopyrite surface. This adsorption increases the flotation rate under certain conditions, and this is beneficial for the flotation of chalcopyrite. The copper ions in the flotation pulp are mainly derived from surface oxidation dissolution and the release of fluid inclusions, and these effects enable chalcopyrite to be activated.展开更多
The effects of copper ions and calcium ions on the depression of chlorite using CMC(carboxymethyl cellulose) as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-pre...The effects of copper ions and calcium ions on the depression of chlorite using CMC(carboxymethyl cellulose) as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-precipitation experiments.The results show that the electrostatic repulsion between the CMC molecules and the chlorite surfaces hinders the approach of the CMC to the chlorite while the presence of copper ions and calcium ions enhances the adsorption density of CMC.The action mechanisms of these two types of ions are different.Calcium ions can not adsorb onto the mineral surfaces,but they can interact with the CMC molecules,thus reducing the charge of the CMC and enhancing adsorption density.Copper ions can adsorb onto the mineral surfaces,which facilitates the CMC adsorption through acid/base interaction.The enhanced adsorption density is also attributed to the decreased electrostatic repulsion between the CMC and mineral surfaces as copper ions reduce the surface charge of both the mineral surfaces and the CMC molecules.展开更多
Platy potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, KMTO) was synthesized by a flux method. The potential application of KMTO in removing copper ions from water pollutants was investigated. The crystal phases of spe...Platy potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, KMTO) was synthesized by a flux method. The potential application of KMTO in removing copper ions from water pollutants was investigated. The crystal phases of specimens were identified by XRD. The morphology and structural information were characterized by SEM and TEM. The adsorption behavior under different conditions was investigated, including different pH values and different initial copper ion concentrations. The results show that the maximum adsorption capacity of Cu(II) ions is 290.697 mg/g, and almost 99.9% of Cu(II) ions can be removed, which is much higher than that of other sorbents reported. The kinetics of KMTO for the adsorption of Cu(II)ions was studied and the best fit can be obtained by the pseudo-second-order model. Adsorption isothermal data can be well interpreted by the Freundlich equation (R2=0.991). In conclusion, this study highlights that KMTO is a potential material for the efficient removal of heavy metal ions in polluted water. It also opens up a new opportunity for the applications of platy KMTO.展开更多
Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable attention.However,improving the fluoresce...Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable attention.However,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great challenge.Herein,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)ligand.TTP-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were proved.More importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).展开更多
The effect and uptake of copper ion on SBR(sequence batch reactor) biological treatment system was studied. Special nutrient and powder activated carbon(PAC) additive were tested as uptake stimulation technique. Resul...The effect and uptake of copper ion on SBR(sequence batch reactor) biological treatment system was studied. Special nutrient and powder activated carbon(PAC) additive were tested as uptake stimulation technique. Results showed that copper ion had higher effect on unacclimated activated sludge system than on acclimated one. The special nutrient adding could enhance the uptake of copper significantly, while PAC adding could improve the sludge settling and decrease the turbidity of effluent. The variation of bacterial community analyzed by 16S rDNA method showed the acclimation of copper could increase copper resistance species, and excess accumulation could cause some species diminish. It was confirmed that acclimation could improve the resistance and uptake ability of microorganism to heavy metal.展开更多
Malachite is one of the main minerals used for the industrial enrichment and recovery of copper oxide resources, and copper ions are unavoidable metal ions in the flotation pulp. The microflotation, contact angle, and...Malachite is one of the main minerals used for the industrial enrichment and recovery of copper oxide resources, and copper ions are unavoidable metal ions in the flotation pulp. The microflotation, contact angle, and adsorption experiments indicated that pretreatment with an appropriate concentration of copper ions could improve the malachite recovery, and the addition of excess copper ions reduced the hydrophobicity of the malachite surface. The results of zeta potential tests indicated that sodium sulfide and butyl xanthate were also adsorbed on the surface of malachite pretreated with copper ions. X-ray photoelectron spectroscopy(XPS) results indicated that —Cu—O and —Cu—OH bonds were formed on the surface of the samples. After pretreatment with an appropriate concentration of copper ions, the number of —OH groups on the mineral surface decreased, whereas the number of Cu—S groups on the mineral surface increased, which was conducive to the sulfidization of malachite. After adding a high concentration of copper ions, the —OH groups on the mineral surface increased, whereas the number of Cu—S groups decreased, which had an adverse effect on the sulfidization flotation of malachite. Time-of-flight secondary ion mass spectrometry showed that pretreatment with copper ions resulted in a thicker sulfidization layer on the mineral surface.展开更多
A magnetic adsorbent can be easily recovered from treated water by magnetic force, without requiring further downstream treatment. In this research, amine-functionalized silica magnetite has been synthesized using N-...A magnetic adsorbent can be easily recovered from treated water by magnetic force, without requiring further downstream treatment. In this research, amine-functionalized silica magnetite has been synthesized using N-[3-(trimethoxysilyl)propyl]-ethylenediamine (TPED) as a surface modification agent. The synthesized magnetic amine adsorbents were used to adsorb copper ions in an aqueous solution in a batch system, and the maximum adsorption was found to occur at pH 5.5± 0. 1. The adsorption equilibrium data fitted the Langmuir isotherm equation reasonably well, with a maximum adsorption capacity of 10.41 mg/g. A pseudo second-order model could best describe the adsorption kinetics, and the derived activation energy was 26.92 kJ/mol. The optimum condition to desorb Cu2+ from NH2/SiO2/Fe304 was provided by a solution with 0.1 mol/L HNO3.展开更多
Under the optimal condition of copper ions adsorption on yeast,we found some different effects among static adsorption, shaking adsorption and negative pressure cavitation adsorption, and the methods of yeast with dif...Under the optimal condition of copper ions adsorption on yeast,we found some different effects among static adsorption, shaking adsorption and negative pressure cavitation adsorption, and the methods of yeast with different pretreatments also affect adsorption of copper ions. At the same time, the change of intercellular pH before and after adsorption of copper with BCECF was studied. The copper distribution was located by using PhenGreen (dipotassium salt and diacetate), and the surface of yeast was observed by an atomic force microscope. The results showed that negative pressure cavitation can improve bioadsorption capacity of copper ions on yeast. However, the yeasts' pretreatment has a higher effect on bioadsorption. It indicates that heavy metal bioadsorption on yeast has much relation with its cellular molecule basis. With the adsorping, the intercellular pH of yeast increased gradually and changed from acidity to alkalescence. These results may suggest that negative pressure cavitation can compel heavy metals to transfer from the cell surface into inside cell and make the surface of yeast coarse.展开更多
Recovery of copper ions from wastewater using a hollow fiber supported emulsion liquid membrane (HFSELM) was studied with LIX984N as carrier, kerosene as diluents, and sulfuric acid solution as stripping phase. Effect...Recovery of copper ions from wastewater using a hollow fiber supported emulsion liquid membrane (HFSELM) was studied with LIX984N as carrier, kerosene as diluents, and sulfuric acid solution as stripping phase. Effects of compositions of feed and emulsion liquid phase, flow rates on both sides of membrane, and hollow fiber module parameters were investigated. The stability of the emulsion liquid phase without surfactant and the effect of buffer in the feed phase on the extraction rate were also evaluated. It is found that the stability of the emulsion phase without surfactant is poor. Higher flow velocity gives shorter residence time for the emulsion liquid phase on the tube side, reducing the effect of particle coalescence on the separation process. The extraction rate increases with the increase of feed phase pH, carrier concentration, hydrogen ion concentration in the stripping phase, and ef- fective hollow fiber area. The phase ratio in the emulsion liquid phase has a negative effect on extraction rate. The flow rates on both sides have little influence on the extraction performance of the HFSELM, while buffer addition in the feed solution improves the extraction efficiency.展开更多
A pyridoxal-based chemosensor was synthesized by reacting hydrazine hydrate and pyridoxal hydrochloride in ethanol and characterized by NMR and ESI-MS. The optical properties of the compound were investigated in a met...A pyridoxal-based chemosensor was synthesized by reacting hydrazine hydrate and pyridoxal hydrochloride in ethanol and characterized by NMR and ESI-MS. The optical properties of the compound were investigated in a methanol: HEPES solution. The compound displayed selectivity for Cu2+, as evidenced by a colorless to yellow color change, which was characterized using UV-vis spectroscopy. The fluorescence of the compound can be quenched only by Cu2+, accompanying by a color change from blue to colorless. Furthermore, it can be used in bioimaging.展开更多
The antifouling of marine facilities placed below the waterline is a key constraint to the development of the marine economy.Currently,commercial Cu_(2)O-based antifouling coatings still have defects such as agglomera...The antifouling of marine facilities placed below the waterline is a key constraint to the development of the marine economy.Currently,commercial Cu_(2)O-based antifouling coatings still have defects such as agglomeration,oxidation,short duration and high dosage.For this reason,we developed for the first time a triple antifouling system consisting of Cu_(2)O@poly(NIPAM-co-DAm)(Cu_(2)O@PND)dynamic redox micro-gels triggered by copper ions and polydimethylsiloxane(PDMS).The catechol groups of PND nanogels can chelate Cu^(2+)and reduce it in situ to obtain Cu_(2)O@PND microgels,which guarantees the stable release of Cu^(+).Furthermore,Cu_(2)O remains stable and free from oxidation because of the electron transfer between PND and Cu^(2+).Finally,superior antifouling performance was achieved by combining the stable Cu^(+)re-leased from Cu_(2)O,in situ conversion of PND to hydrogel,and its oxidation to produce active substances and H_(2)O_(2),and PDMS coating with low surface energy.展开更多
The dissolution mechanism of marmatite in the presence of Cu^(2+)was intensively studied by experiments and density functional theory(DFT)calculations.Leaching experiments showed that Cu^(2+)accelerated marmatite diss...The dissolution mechanism of marmatite in the presence of Cu^(2+)was intensively studied by experiments and density functional theory(DFT)calculations.Leaching experiments showed that Cu^(2+)accelerated marmatite dissolution at high temperatures(above 55℃),but the trend was reversed at low temperatures(below 45℃),which may be because the reaction mechanism between Cu^(2+)and marmatite changed from surface adsorption to bulk substitution with increasing temperature.The substitution reaction caused more zinc atoms in the marmatite crystal lattice to be released and enhanced the electrochemical reactivity,while the adsorption of copper ions at low temperatures would passivate marmatite,thus inhibiting the reaction process.DFT calculations showed that the energy of the substitution reaction was more negative than that of the adsorption reaction at high temperatures,which further verified the proposed mechanism.展开更多
Antibacterial activity of AISI420 stainless steel (SS) implanted by copper was investigated. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 100keV energy and a dose range from 0.2×1017 to 2...Antibacterial activity of AISI420 stainless steel (SS) implanted by copper was investigated. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 100keV energy and a dose range from 0.2×1017 to 2.0×1017ions·cm-2. The saturation dose of Cu implantation in AISI420 SS and Cu surface concentration were calculated at the energy of 100keV. The effect of dose on the antibacterial activity was analyzed. Results of antibacterial test show that the saturation dose is the optimum implantation dose for best antibacterial activity, which is above 99% against both Escherichia coli and Staphylococcus aureus. Novel phases such as Fe4Cu3 and Cu9.9Fe0.1 were found in the implanted layer by glancing angle X-ray diffraction (GXRD). The antibacterial activity of AISI420 SS attributes to Cu-contained phase.展开更多
This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of he- patic fibrosis ...This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of he- patic fibrosis in Wilson's disease. LX-2 cells, a cell line of human HSCs, were cultured in vitro and treated with different agents including copper sulfate, N-acetyl cysteine (NAC) and buthionine sulfoxi- mine (BSO) for different time. The proliferation of LX-2 cells was measured by non-radioactive cell proliferation assay. Real-time PCR and Westem blotting were used to detect the mRNA and protein ex- pression of platelet-derived growth factor receptor 13 subunit (PDGFI3R), ELISA to determine the level of glutathione (GSH) and oxidized glutathione (GSSG), dichlorofluorescein assay to measure the level of reactive oxygen species (ROS), and lipid hydroperoxide assay to quantify the level of lipid peroxide (LPO). The results showed that copper sulfate over a certain concentration range could promote the pro- liferation of LX-2 cells in a time- and dose-dependent manner. The effect was most manifest when LX-2 cells were treated with copper sulfate at a concentration of 100 ~tmol/L for 24 h. Additionally, copper sulfate could dose-dependently increase the levels of ROS and LPO, and decrease the ratio of GSH/GSSG in LX-2 cells. The copper-induced increase in mRNA and protein expression of PDGF^R was significantly inhibited in LX-2 cells pre-treated with NAC, a precursor of GSH, and this phenome- non could be reversed by the intervention of BSO, an inhibitor of NAC. It was concluded that copper ions may directly stimulate the proliferation of HSCs via oxidative stress. Anti-oxidative stress therapies may help suppress the copper-induced activation and proliferation of HSCs.展开更多
Biocompatible and high content grafted carboxymethyl cellulose-g-poly(acrylic acid)powder was successfully synthesized in an aqueous system,and used as adsorbents for the removal of Cu(II)in aqueous solution.The copol...Biocompatible and high content grafted carboxymethyl cellulose-g-poly(acrylic acid)powder was successfully synthesized in an aqueous system,and used as adsorbents for the removal of Cu(II)in aqueous solution.The copolymer was characterized by FT-IR and SEM techniques.Graft copolymerization introduced a large number of carboxyl groups in the polymer and caused the micro-surface of the material to be porous.The fundamental adsorption behaviors of the material were studied.The adsorption kinetics was well fitted with pseudo-second order equation,while the adsorption isotherm preferred to be described the Langmuir equation.The maximum adsorption capacity obtained from the Langmuir model was 154.32 mg/g,indicating that the adsorption capacity of carboxymethyl cellulose was improved remarkably after grafting poly(acrylic acid).Moreover,Fourier transform infrared spectroscopy(FT-IR)has been used to investigate the adsorption mechanisms at molecular levels,which revealed that carboxyl groups are facile to form bidentate carboxylates with metal ions.Thus,this environment friendly copolymer will be a promising candidate for application in removal of heavy metal ions.展开更多
Superoxide dismutase(SOD) is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainl...Superoxide dismutase(SOD) is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainly two specific forms, Cu/Zn-SOD(SOD1) and Mn-SOD(SOD2), in eukaryotes. SODs are known to be concurrently modulated by a variety of environmental stressors. By using central composite experimental design and response surface method, the joint effects of water temperature(18–34°C) and copper ion concentration(0.1–1.5 mg/L) on the total SOD activity in the digestive gland of Crassostrea ariakensis were studied. The results showed that the linear effect of temperature was highly significant(P〈0.01), the quadratic effect of temperature was significant(P〈0.05); the linear effect of copper ion concentration was not significant(P〉0.05), while the quadratic effect of copper ion concentration was highly significant(P〈0.01); the interactive effect of temperature and copper ion concentration was not significant(P〉0.05); the effect of temperature was greater than that of copper ion concentration. The model equation of digestive gland SOD enzyme activity towards the two factors of interest was established, with R2 and predictive R2 as high as 0.961 6 and 0.820 7, respectively, suggesting that the goodness-offit to experimental data be very satisfactory, and could be applied to prediction of digestive gland SOD activity in C. ariakensis under the conditions of the experiment. Our results would be conducive to addressing the health of aquatic animals and/or to detecting environmental problems by taking SOD as a potential bioindicator.展开更多
Silver nanoplates as novel optical sensors for Cu^2+ detection have been demonstrated.Silver nanoplates are synthesized via previous H_2O_2-NaBH_4 cyclic oxidation-reduction reactions.With introduction of ascorbate a...Silver nanoplates as novel optical sensors for Cu^2+ detection have been demonstrated.Silver nanoplates are synthesized via previous H_2O_2-NaBH_4 cyclic oxidation-reduction reactions.With introduction of ascorbate as mild reductants,Cu^2+ ions are reduced into Cu~+ and the Cu^+ is further reduced to Cu,which is deposited on the surface of the silver nanoplates.The deposition of the Cu on the surface of the silver nanoplates allows a significant red-shift of their plasmon absorption.Therefore,trace Cu^2+ can be detected.The shift of the plasmon absorption wavelength of silver nanoplates is proportional to the Cu^2+concentration over a range of 40-340 μmol L^(-1) with a limit of detection of 9.0 μmol L^(-1).Moreover,such silver nanoplate-based optical sensors provide good selectivity for Cu^2+ detection,and most other metal ions do not disturb its detection.Moreover,the practicality of the proposed sensor was tested.This Cu^2+assay is advantageous in its simplicity,selectivity,and cost-effectiveness.展开更多
Transport of copper ions through nanocomposite chitosan/polyvinyl alcohol thin adsorptive membranes has been mathematically investigated in the current study. Unsteady-state diffusive transport model was coupled with ...Transport of copper ions through nanocomposite chitosan/polyvinyl alcohol thin adsorptive membranes has been mathematically investigated in the current study. Unsteady-state diffusive transport model was coupled with the Freundlich isotherm to predict the concentration of the ions in dialysis permeation operation. Pristine model was not successful in predicting the experimental data based upon its low coefficients of determination(0.1展开更多
A central composite experimental design and response surface method were used to investigate the combined effects of water temperature(18–34℃) and copper ion concentration(0.1–1.5 mg/L) on the catalase(CAT) activit...A central composite experimental design and response surface method were used to investigate the combined effects of water temperature(18–34℃) and copper ion concentration(0.1–1.5 mg/L) on the catalase(CAT) activity in the digestive gland of C rassostrea ariakensis. The results showed that the linear effects of temperature were significant(P <0.01), the quadratic effects of temperature were significant( P <0.05), the linear effects of copper ion concentration were not significant(P >0.05), and the quadratic effects of copper ion concentration were significant(P <0.05). Additionally, the synergistic effects of temperature and copper ion concentration were not significant(P >0.05), and the effect of temperature was greater than that of copper ion concentration. A model equation of CAT enzyme activity in the digestive gland of C. ariakensis toward the two factors of interest was established, with R 2, Adj. R 2 and Pred. R 2 values as high as 0.943 7, 0.887 3 and 0.838 5, respectively. These findings suggested that the goodness of fit to experimental data and predictive capability of the model were satisfactory, and could be practically applied for prediction under the conditions of the study. Overall, the results suggest that the simultaneous variation of temperature and copper ion concentration alters the activity of the antioxidant enzyme CAT by modulating active oxygen species metabolism, which may be utilized as a biomarker to detect the effects of copper pollution.展开更多
基金supported by the Nano Material Technology Development Program(2021M3H4A1A02057007)funded by the Ministry of Science and ICT through the National Research Foundation of Koreasupported by the Basic Science Research Program through NRF funded by the Ministry of Education(2022R1A6A1A03051158,2022R1A2C4002248,RS-202300247069)。
文摘The limited charge extraction efficiency and suboptimal energy-level alignment of poly(3,4-ethylenediox ythiophene)polystyrene sulfonate(PEDOT:PSS)as a hole transport layer restrict its performance in solar cell applications.In this study,we developed effective copper-ion(Cu(Ⅱ))-modified oxyl-terminated melem two-dimensional(2D)nanodisks(Cu(Ⅱ)@OMN)that improved the performance of PEDOT:PSS as a representative hole-transport layer(HTL)in organic and perovskite solar cells.Based on theoretical calculations and experimental data,the interaction between Cu(Ⅱ)@OMN and PEDOT or PSS led to electron redistribution in PEDOT:PSS and the dissociation of PEDOT and PSS,promoting enhanced charge extraction and transfer.In addition,the work function of the Cu(Ⅱ)@OMN-PEDOT:PSS is modified to achieve a more beneficial energy-level alignment,thereby facilitating improved hole transport and inhibited nonradiative recombination.Methylammonium(MA)-based perovskite and organic binary PM6:Y6solar cells achieved power conversion efficiencies(PCEs)of 19.21% and 17.15%,respectively.These PCEs are among the highest reported for MA-based perovskite and binary PM6:Y6 organic solar cells that use 2D nanomaterial-modified PEDOT:PSS,demonstrating the potential of Cu(Ⅱ)@OMN in solar cell applications.
基金Projects(51464029,51168020,51404119,)supported by the National Natural Science Foundation of ChinaProject(2014Y084)supported by the Natural Science Foundation of Yunnan Province Education Department,ChinaProjects(41118011,201421066)supported by the Cultivation Program of Kunming University of Science and Technology,China
文摘The adsorption behaviors of copper ions on chalcopyrite surfaces were investigated based on zeta potential measurements, X-ray photoelectron spectroscopy, copper ion adsorption experiments, first-principles calculations, and Hallimond tube cell flotation experiments. The results show that copper ions activate the chalcopyrite as a result of the interactions between copper ions and sulfur on the chalcopyrite surface. This adsorption increases the flotation rate under certain conditions, and this is beneficial for the flotation of chalcopyrite. The copper ions in the flotation pulp are mainly derived from surface oxidation dissolution and the release of fluid inclusions, and these effects enable chalcopyrite to be activated.
基金Project(51174229) supported by the National Natural Science Foundation of China
文摘The effects of copper ions and calcium ions on the depression of chlorite using CMC(carboxymethyl cellulose) as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-precipitation experiments.The results show that the electrostatic repulsion between the CMC molecules and the chlorite surfaces hinders the approach of the CMC to the chlorite while the presence of copper ions and calcium ions enhances the adsorption density of CMC.The action mechanisms of these two types of ions are different.Calcium ions can not adsorb onto the mineral surfaces,but they can interact with the CMC molecules,thus reducing the charge of the CMC and enhancing adsorption density.Copper ions can adsorb onto the mineral surfaces,which facilitates the CMC adsorption through acid/base interaction.The enhanced adsorption density is also attributed to the decreased electrostatic repulsion between the CMC and mineral surfaces as copper ions reduce the surface charge of both the mineral surfaces and the CMC molecules.
基金Project(51272289)supported by the National Natural Science Foundation of ChinaProject(51021063)supported by the Creative Research Group of National Science Foundation of China
文摘Platy potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, KMTO) was synthesized by a flux method. The potential application of KMTO in removing copper ions from water pollutants was investigated. The crystal phases of specimens were identified by XRD. The morphology and structural information were characterized by SEM and TEM. The adsorption behavior under different conditions was investigated, including different pH values and different initial copper ion concentrations. The results show that the maximum adsorption capacity of Cu(II) ions is 290.697 mg/g, and almost 99.9% of Cu(II) ions can be removed, which is much higher than that of other sorbents reported. The kinetics of KMTO for the adsorption of Cu(II)ions was studied and the best fit can be obtained by the pseudo-second-order model. Adsorption isothermal data can be well interpreted by the Freundlich equation (R2=0.991). In conclusion, this study highlights that KMTO is a potential material for the efficient removal of heavy metal ions in polluted water. It also opens up a new opportunity for the applications of platy KMTO.
基金This study was financially supported by the National Natural Science Foundation of China(Nos.22001156 and 22271178)the Innovation Capability Support Program of Shaanxi(No.2022KJXX-88)the Technology Innovation Leading Program of Shaanxi(No.2020QFY07-05).
文摘Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable attention.However,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great challenge.Herein,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)ligand.TTP-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were proved.More importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).
基金ShanghaiEnvironmentalProtectionBureau (No .0 2JG0 5 0 3 0 )
文摘The effect and uptake of copper ion on SBR(sequence batch reactor) biological treatment system was studied. Special nutrient and powder activated carbon(PAC) additive were tested as uptake stimulation technique. Results showed that copper ion had higher effect on unacclimated activated sludge system than on acclimated one. The special nutrient adding could enhance the uptake of copper significantly, while PAC adding could improve the sludge settling and decrease the turbidity of effluent. The variation of bacterial community analyzed by 16S rDNA method showed the acclimation of copper could increase copper resistance species, and excess accumulation could cause some species diminish. It was confirmed that acclimation could improve the resistance and uptake ability of microorganism to heavy metal.
基金supported by Yunnan Fundamental Research Projects (No. 202101BE070001-009)Open Foundation of State Key Laboratory of Mineral Processing (No. BGRIMM-KJSKL-202124)Ten Thousand Talent Plans for Young Top-notch Talents of Yunnan Province (No. YNWR-QNBJ-2018-051)。
文摘Malachite is one of the main minerals used for the industrial enrichment and recovery of copper oxide resources, and copper ions are unavoidable metal ions in the flotation pulp. The microflotation, contact angle, and adsorption experiments indicated that pretreatment with an appropriate concentration of copper ions could improve the malachite recovery, and the addition of excess copper ions reduced the hydrophobicity of the malachite surface. The results of zeta potential tests indicated that sodium sulfide and butyl xanthate were also adsorbed on the surface of malachite pretreated with copper ions. X-ray photoelectron spectroscopy(XPS) results indicated that —Cu—O and —Cu—OH bonds were formed on the surface of the samples. After pretreatment with an appropriate concentration of copper ions, the number of —OH groups on the mineral surface decreased, whereas the number of Cu—S groups on the mineral surface increased, which was conducive to the sulfidization of malachite. After adding a high concentration of copper ions, the —OH groups on the mineral surface increased, whereas the number of Cu—S groups decreased, which had an adverse effect on the sulfidization flotation of malachite. Time-of-flight secondary ion mass spectrometry showed that pretreatment with copper ions resulted in a thicker sulfidization layer on the mineral surface.
文摘A magnetic adsorbent can be easily recovered from treated water by magnetic force, without requiring further downstream treatment. In this research, amine-functionalized silica magnetite has been synthesized using N-[3-(trimethoxysilyl)propyl]-ethylenediamine (TPED) as a surface modification agent. The synthesized magnetic amine adsorbents were used to adsorb copper ions in an aqueous solution in a batch system, and the maximum adsorption was found to occur at pH 5.5± 0. 1. The adsorption equilibrium data fitted the Langmuir isotherm equation reasonably well, with a maximum adsorption capacity of 10.41 mg/g. A pseudo second-order model could best describe the adsorption kinetics, and the derived activation energy was 26.92 kJ/mol. The optimum condition to desorb Cu2+ from NH2/SiO2/Fe304 was provided by a solution with 0.1 mol/L HNO3.
基金The National Basic Research Program (973) of China (No. 2004CB418505)
文摘Under the optimal condition of copper ions adsorption on yeast,we found some different effects among static adsorption, shaking adsorption and negative pressure cavitation adsorption, and the methods of yeast with different pretreatments also affect adsorption of copper ions. At the same time, the change of intercellular pH before and after adsorption of copper with BCECF was studied. The copper distribution was located by using PhenGreen (dipotassium salt and diacetate), and the surface of yeast was observed by an atomic force microscope. The results showed that negative pressure cavitation can improve bioadsorption capacity of copper ions on yeast. However, the yeasts' pretreatment has a higher effect on bioadsorption. It indicates that heavy metal bioadsorption on yeast has much relation with its cellular molecule basis. With the adsorping, the intercellular pH of yeast increased gradually and changed from acidity to alkalescence. These results may suggest that negative pressure cavitation can compel heavy metals to transfer from the cell surface into inside cell and make the surface of yeast coarse.
基金Supported by the National Natural Science Foundation of China (20676023)
文摘Recovery of copper ions from wastewater using a hollow fiber supported emulsion liquid membrane (HFSELM) was studied with LIX984N as carrier, kerosene as diluents, and sulfuric acid solution as stripping phase. Effects of compositions of feed and emulsion liquid phase, flow rates on both sides of membrane, and hollow fiber module parameters were investigated. The stability of the emulsion liquid phase without surfactant and the effect of buffer in the feed phase on the extraction rate were also evaluated. It is found that the stability of the emulsion phase without surfactant is poor. Higher flow velocity gives shorter residence time for the emulsion liquid phase on the tube side, reducing the effect of particle coalescence on the separation process. The extraction rate increases with the increase of feed phase pH, carrier concentration, hydrogen ion concentration in the stripping phase, and ef- fective hollow fiber area. The phase ratio in the emulsion liquid phase has a negative effect on extraction rate. The flow rates on both sides have little influence on the extraction performance of the HFSELM, while buffer addition in the feed solution improves the extraction efficiency.
基金supported by the National Natural Science Foundation of China (No.21102086)the Shanxi Province Science Foundation for Youths (Nos.2012021009-4 and 2013011011-1)+4 种基金the Shanxi Province Foundation for Returnee (No.2012-007)the Taiyuan Technology Star Special (No.12024703)the Program for the Top Young and Middle-aged Innovative Talents of Higher Learning Institutions of Shanxi (TYMIT,No.2013802)talents Support Program of Shanxi Province (No.2014401)CAS Key Laboratory of Analytical Chemistry for Living Biosystems Open Foundation (No.ACL201304)
文摘A pyridoxal-based chemosensor was synthesized by reacting hydrazine hydrate and pyridoxal hydrochloride in ethanol and characterized by NMR and ESI-MS. The optical properties of the compound were investigated in a methanol: HEPES solution. The compound displayed selectivity for Cu2+, as evidenced by a colorless to yellow color change, which was characterized using UV-vis spectroscopy. The fluorescence of the compound can be quenched only by Cu2+, accompanying by a color change from blue to colorless. Furthermore, it can be used in bioimaging.
基金financially supported by the National Natural Science Foundation of China (No.52073311)the Guangdong Basic and Applied Basic Research Foundation (Nos.2020A1515011274 and 2021A1515012281).
文摘The antifouling of marine facilities placed below the waterline is a key constraint to the development of the marine economy.Currently,commercial Cu_(2)O-based antifouling coatings still have defects such as agglomeration,oxidation,short duration and high dosage.For this reason,we developed for the first time a triple antifouling system consisting of Cu_(2)O@poly(NIPAM-co-DAm)(Cu_(2)O@PND)dynamic redox micro-gels triggered by copper ions and polydimethylsiloxane(PDMS).The catechol groups of PND nanogels can chelate Cu^(2+)and reduce it in situ to obtain Cu_(2)O@PND microgels,which guarantees the stable release of Cu^(+).Furthermore,Cu_(2)O remains stable and free from oxidation because of the electron transfer between PND and Cu^(2+).Finally,superior antifouling performance was achieved by combining the stable Cu^(+)re-leased from Cu_(2)O,in situ conversion of PND to hydrogel,and its oxidation to produce active substances and H_(2)O_(2),and PDMS coating with low surface energy.
基金supported by the National Natural Science Foundation of China(No.52174266)the State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming,China(No.CNMRCUKF2109)the Education Foundation of Central South University,China(No.GCY2021376Y)。
文摘The dissolution mechanism of marmatite in the presence of Cu^(2+)was intensively studied by experiments and density functional theory(DFT)calculations.Leaching experiments showed that Cu^(2+)accelerated marmatite dissolution at high temperatures(above 55℃),but the trend was reversed at low temperatures(below 45℃),which may be because the reaction mechanism between Cu^(2+)and marmatite changed from surface adsorption to bulk substitution with increasing temperature.The substitution reaction caused more zinc atoms in the marmatite crystal lattice to be released and enhanced the electrochemical reactivity,while the adsorption of copper ions at low temperatures would passivate marmatite,thus inhibiting the reaction process.DFT calculations showed that the energy of the substitution reaction was more negative than that of the adsorption reaction at high temperatures,which further verified the proposed mechanism.
基金This work was supported by the National Natural Science Foundation of China(No.50101009)
文摘Antibacterial activity of AISI420 stainless steel (SS) implanted by copper was investigated. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 100keV energy and a dose range from 0.2×1017 to 2.0×1017ions·cm-2. The saturation dose of Cu implantation in AISI420 SS and Cu surface concentration were calculated at the energy of 100keV. The effect of dose on the antibacterial activity was analyzed. Results of antibacterial test show that the saturation dose is the optimum implantation dose for best antibacterial activity, which is above 99% against both Escherichia coli and Staphylococcus aureus. Novel phases such as Fe4Cu3 and Cu9.9Fe0.1 were found in the implanted layer by glancing angle X-ray diffraction (GXRD). The antibacterial activity of AISI420 SS attributes to Cu-contained phase.
文摘This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of he- patic fibrosis in Wilson's disease. LX-2 cells, a cell line of human HSCs, were cultured in vitro and treated with different agents including copper sulfate, N-acetyl cysteine (NAC) and buthionine sulfoxi- mine (BSO) for different time. The proliferation of LX-2 cells was measured by non-radioactive cell proliferation assay. Real-time PCR and Westem blotting were used to detect the mRNA and protein ex- pression of platelet-derived growth factor receptor 13 subunit (PDGFI3R), ELISA to determine the level of glutathione (GSH) and oxidized glutathione (GSSG), dichlorofluorescein assay to measure the level of reactive oxygen species (ROS), and lipid hydroperoxide assay to quantify the level of lipid peroxide (LPO). The results showed that copper sulfate over a certain concentration range could promote the pro- liferation of LX-2 cells in a time- and dose-dependent manner. The effect was most manifest when LX-2 cells were treated with copper sulfate at a concentration of 100 ~tmol/L for 24 h. Additionally, copper sulfate could dose-dependently increase the levels of ROS and LPO, and decrease the ratio of GSH/GSSG in LX-2 cells. The copper-induced increase in mRNA and protein expression of PDGF^R was significantly inhibited in LX-2 cells pre-treated with NAC, a precursor of GSH, and this phenome- non could be reversed by the intervention of BSO, an inhibitor of NAC. It was concluded that copper ions may directly stimulate the proliferation of HSCs via oxidative stress. Anti-oxidative stress therapies may help suppress the copper-induced activation and proliferation of HSCs.
基金by the Visiting Research Scholar Project for Young/Middle Excellent Talents of Anhui Province(gxfx2017044)National Natural Science Foundation of China(31700499).
文摘Biocompatible and high content grafted carboxymethyl cellulose-g-poly(acrylic acid)powder was successfully synthesized in an aqueous system,and used as adsorbents for the removal of Cu(II)in aqueous solution.The copolymer was characterized by FT-IR and SEM techniques.Graft copolymerization introduced a large number of carboxyl groups in the polymer and caused the micro-surface of the material to be porous.The fundamental adsorption behaviors of the material were studied.The adsorption kinetics was well fitted with pseudo-second order equation,while the adsorption isotherm preferred to be described the Langmuir equation.The maximum adsorption capacity obtained from the Langmuir model was 154.32 mg/g,indicating that the adsorption capacity of carboxymethyl cellulose was improved remarkably after grafting poly(acrylic acid).Moreover,Fourier transform infrared spectroscopy(FT-IR)has been used to investigate the adsorption mechanisms at molecular levels,which revealed that carboxyl groups are facile to form bidentate carboxylates with metal ions.Thus,this environment friendly copolymer will be a promising candidate for application in removal of heavy metal ions.
基金The Guangdong Province Education Department under contract No.GCZX-A0909the Guangdong Province Ocean and Fisheries Science & Technology Extension Project under contract No.20120980+1 种基金the Guangdong Province Industry-University-Science Partnership Project under contract No.20110908the Science&Technology Project of Huaiyin Normal University under contract No.WH0031
文摘Superoxide dismutase(SOD) is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainly two specific forms, Cu/Zn-SOD(SOD1) and Mn-SOD(SOD2), in eukaryotes. SODs are known to be concurrently modulated by a variety of environmental stressors. By using central composite experimental design and response surface method, the joint effects of water temperature(18–34°C) and copper ion concentration(0.1–1.5 mg/L) on the total SOD activity in the digestive gland of Crassostrea ariakensis were studied. The results showed that the linear effect of temperature was highly significant(P〈0.01), the quadratic effect of temperature was significant(P〈0.05); the linear effect of copper ion concentration was not significant(P〉0.05), while the quadratic effect of copper ion concentration was highly significant(P〈0.01); the interactive effect of temperature and copper ion concentration was not significant(P〉0.05); the effect of temperature was greater than that of copper ion concentration. The model equation of digestive gland SOD enzyme activity towards the two factors of interest was established, with R2 and predictive R2 as high as 0.961 6 and 0.820 7, respectively, suggesting that the goodness-offit to experimental data be very satisfactory, and could be applied to prediction of digestive gland SOD activity in C. ariakensis under the conditions of the experiment. Our results would be conducive to addressing the health of aquatic animals and/or to detecting environmental problems by taking SOD as a potential bioindicator.
基金supported by the National Natural Science Foundation of China(No.21375036)the Open Project Program of Key Laboratory of Theoretical Chemistry and Molecular Simulation of Ministry of Education(Hunan University of Science and Technology,No.E21201)
文摘Silver nanoplates as novel optical sensors for Cu^2+ detection have been demonstrated.Silver nanoplates are synthesized via previous H_2O_2-NaBH_4 cyclic oxidation-reduction reactions.With introduction of ascorbate as mild reductants,Cu^2+ ions are reduced into Cu~+ and the Cu^+ is further reduced to Cu,which is deposited on the surface of the silver nanoplates.The deposition of the Cu on the surface of the silver nanoplates allows a significant red-shift of their plasmon absorption.Therefore,trace Cu^2+ can be detected.The shift of the plasmon absorption wavelength of silver nanoplates is proportional to the Cu^2+concentration over a range of 40-340 μmol L^(-1) with a limit of detection of 9.0 μmol L^(-1).Moreover,such silver nanoplate-based optical sensors provide good selectivity for Cu^2+ detection,and most other metal ions do not disturb its detection.Moreover,the practicality of the proposed sensor was tested.This Cu^2+assay is advantageous in its simplicity,selectivity,and cost-effectiveness.
文摘Transport of copper ions through nanocomposite chitosan/polyvinyl alcohol thin adsorptive membranes has been mathematically investigated in the current study. Unsteady-state diffusive transport model was coupled with the Freundlich isotherm to predict the concentration of the ions in dialysis permeation operation. Pristine model was not successful in predicting the experimental data based upon its low coefficients of determination(0.1
基金Supported by the Guangdong Province Science & Technology Project(No.2010B020201014)the Guangdong Province Education Department(No.GCZX-A0909)+2 种基金the Guangdong Province Ocean and Fisheries Science & Technology Extension Project(No.20120980)the Guangdong Province Industry-University-Science Partnership Project(No.20110908)the Sci & Tech Plan of Huaiyin Normal University(No.00wh0031)
文摘A central composite experimental design and response surface method were used to investigate the combined effects of water temperature(18–34℃) and copper ion concentration(0.1–1.5 mg/L) on the catalase(CAT) activity in the digestive gland of C rassostrea ariakensis. The results showed that the linear effects of temperature were significant(P <0.01), the quadratic effects of temperature were significant( P <0.05), the linear effects of copper ion concentration were not significant(P >0.05), and the quadratic effects of copper ion concentration were significant(P <0.05). Additionally, the synergistic effects of temperature and copper ion concentration were not significant(P >0.05), and the effect of temperature was greater than that of copper ion concentration. A model equation of CAT enzyme activity in the digestive gland of C. ariakensis toward the two factors of interest was established, with R 2, Adj. R 2 and Pred. R 2 values as high as 0.943 7, 0.887 3 and 0.838 5, respectively. These findings suggested that the goodness of fit to experimental data and predictive capability of the model were satisfactory, and could be practically applied for prediction under the conditions of the study. Overall, the results suggest that the simultaneous variation of temperature and copper ion concentration alters the activity of the antioxidant enzyme CAT by modulating active oxygen species metabolism, which may be utilized as a biomarker to detect the effects of copper pollution.