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
ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced...ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced by the X-ray diffraction and scanning electron microscopy results.The lattice constants,as determined by X-ray diffraction,contradict the disparity in Ta and Zn ion radii,which is attributed to the impact of interstitial defects.This inconsistency introduces variations in carrier concentration in this experiment compared with prior studies.Subsequent exploration of the luminescent characteristics and emission mechanism of defect levels in Ta-doped ZnO films was conducted through photoluminescence.Furthermore,the factors influencing the bandgap are discussed.展开更多
Here,a preparation of stable,non-toxic,transparent,high performance zinc oxide thin-film semiconductor via thermal processing of composite system of zinc source solution filled zinc oxide nanoparticles layer was repor...Here,a preparation of stable,non-toxic,transparent,high performance zinc oxide thin-film semiconductor via thermal processing of composite system of zinc source solution filled zinc oxide nanoparticles layer was reported.The zinc oxide nanocrystals synthesized through the thermolysis of Zn-oleate complex in organic solvent medium were first deposited on the ATO/ITO/glass substrate and treated by annealing,then the zinc source solution was deposited on the zinc oxide nanoparticle layer to form precursor thin film by spin-coating process.The thin film transistor with well-controlled and densely packed nanocrystals in zinc oxide semiconductor layer was obtained by thermal annealing the system of precursor film coated ATO/ITO/glass substrate.By optimizing the fabrication conditions,the fabricated thin film transistors exhibited superior field-effect property and carrier mobility property,their saturation mobility reached 2.17 cm^(2)·V^(-1)·s^(-1),which was more than twice as high compared to the transistor devices coated only by zinc oxide nanoparticles.Our method of fabricating zinc oxide thin film transistors was simple,high efficiency,and feasible for the batch production with low cost.展开更多
Objective:To examine the protective effects of green-synthesized zinc oxide nanoparticles with Berberis vulgaris L.fruit aqueous extract(BVZnONPs)on cyclophosphamide(CP)-induced nephrotoxicity in Wistar rats.Methods:3...Objective:To examine the protective effects of green-synthesized zinc oxide nanoparticles with Berberis vulgaris L.fruit aqueous extract(BVZnONPs)on cyclophosphamide(CP)-induced nephrotoxicity in Wistar rats.Methods:35 Adult male Wistar rats were divided into 5 groups:normal,BVZnONPs(20 mg/kg),CP(100 mg/kg),and 2 co-treatment groups receiving CP with BVZnONPs(10 and 20 mg/kg).All treatments were administered intraperitoneally for 28 days.Serum levels of antioxidant enzymes(catalase,superoxide dismutase,glutathione peroxidase,nitric oxide)and kidney function parameters(creatinine,total protein,blood urea nitrogen)were measured.The expressions of p53 and Bcl-2 proteins were assessed via immunohistochemical assay while kidney volume and substructures were estimated stereologically.Results:CP induced nephrotoxicity with significant increases(P<0.05)in nitric oxide,creatinine,and blood urea nitrogen levels,and decreases(P<0.05)in catalase,superoxide dismutase,and glutathione peroxidase levels.It also increased p53 protein expression and decreased Bcl-2 protein expression.Treatment with BVZnONPs significantly increased(P<0.05)antioxidant enzyme levels and decreased nitric oxide levels in the 20 mg/kg group compared to CP.Blood urea nitrogen and creatinine levels were significantly reduced in the BVZnONPs-treated groups,with greater effects at 20 mg/kg.However,total protein serum levels were not significant(P>0.05)in the BVZnONPs-treated groups compared to CP.Conclusions:These findings suggest that BVZnONPs can mitigate CP-induced nephrotoxicity,likely due to their antioxidant and anti-apoptotic properties,though longer treatment duration may be necessary for tissue-level improvements.展开更多
Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.T...Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles(Cin@CSNPs)against oxidative damage and genotoxicity of ZnO-NPs in mice.ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L.Cin was extracted from cinnamon essential oil,and was loaded into chitosan nanoparticle(Cin@CSNPs).Both ZnO-NPs,Cin@CSNPs and CSNPs were characterized.The in vitro release of Cin@CSNPs was determined.In the biological study,6 groups of male BALB/c mice were treated by gavage for 3 weeks as follows,control group,the group received ZnO-NPs(25 mg/kg b.w),the groups received Cin@CSNPs at low dose(50 mg/kg b.w)or high dose(100 mg/kg b.w),and the groups received ZnO-NPs plus Cin@CSNPs at the 2 tested doses.Blood and tissue samples were collected for different biochemical,genetical and histological studies.The particle size of ZnO-NPs,CSNPs,and Cin@CSNPs were(20.78±2.60),(170.0±3.7),and(218.23±2.90)nm,andξ-potential were(32.7±4.6),(8.32±0.27)and(4.80±0.21)mV,respectively.ZnO-NPs disturbed the biochemical and oxidative stress indices,AFP,CEA,TNF-α,chromosomal aberrations in somatic and germ cells,and sperm abnormality along with severe pathological changes in the hepatic,renal,and testicular tissues.Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent.Therefore,the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity,and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.展开更多
Oxidation of As^Ⅲ by three types of manganese oxide minerals affected by goethite was investigated by chemical analysis, equilibrium redox, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. Thre...Oxidation of As^Ⅲ by three types of manganese oxide minerals affected by goethite was investigated by chemical analysis, equilibrium redox, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. Three synthesized Mn oxide minerals of different types, birnessite, todorokite, and hausmannite, could actively oxidize As^Ⅲ to Asv, and greatly varied in their oxidation ability. Layer structured birnessite exhibited the highest capacity of As^Ⅲ oxidation, followed by the tunnel structured todorokite. Lower oxide hansmannite possessed much low capacity of As^Ⅲ oxidation, and released more Mn^2＋ than birnessite and todorokite during the oxidation. The maximum amount of Asv produced during the oxidation of As^Ⅲ by Mn oxide minerals was in the order： birnessite （480.4 mmol/kg） 〉 todorokite （279.6 mmol/kg） 〉 hansmannite （117.9 mmol/kg）. The oxidation capacity of the Mn oxide minerals was found to be relative to the composition, crystallinity, and surface properties. In the presence of goethite oxidation of As^Ⅲ by Mn oxide minerals increased, with maximum amounts of Asv being 651.0 mmol/kg for birnessite, 332.3 mmol/kg for todorokite and 159.4 mmol/kg for hansmannite. Goethite promoted As^Ⅲ oxidation on the surface of Mn oxide minerals through adsorption of the Asv produced, incurring the decrease of Asv concentration in solutions. Thus, the combined effects of the oxidation （by Mn oxide minerals）-adsorption （by goethite） lead to rapid oxidation and immobilization of As in soils and sediments and alleviation of the As^Ⅲ toxicity in the environments.展开更多
Although the enhancement of the zinc storage performance of layered vanadium oxides can be realized by the ionic pre-intercalation strategy,it also occupies a large number of active sites and thus fails to release the...Although the enhancement of the zinc storage performance of layered vanadium oxides can be realized by the ionic pre-intercalation strategy,it also occupies a large number of active sites and thus fails to release the full potential of vanadium oxides.Here,vanadium oxide nanobelts with sodium-poor and oxygen defect-rich were constructed by regulating the content of pre-embedded sodium ions to strike a balance between pre-embedded ions and structural stability.The introduction of trace sodium ions not only increases the spacing of vanadium oxide layers but also occupies as few active sites as possible,which provides the possibility of massive storage,rapid diffusion and stabilization of the host structure for zinc ions.Moreover,the abundant oxygen defects transform the ion transport pathway from two-dimensional to three-dimensional,which greatly improves the ion transport rate in the host phase.Due to these advantages,the synthesized vanadium oxide nanobelts exhibit remarkable electrochemical properties,and this work provides a new idea for the design of structurally stable layered vanadium oxides with excellent properties.展开更多
Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of ...Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of Zn O:Ga(GZO)in nuclear energy is particularly significant and fascinating at the fundamental level,enabling neutron/gamma discrimination while preserving the response time properties of the single crystal in sub-nanoseconds,maximizing the effective counting rate of the pulsed radiation field.In this study,the single-particle waveform discrimination characteristics of GZO were evaluated for five charged particles(α,β,H^(+),Li^(+),and O^(8+)and two prevalent uncharged particles(neutrons and gamma rays).Based on the timecorrelation single-photon counting(TCSPC)method,the luminescence decay time constants of the charged particles in the GZO crystal were determined as follows:1.21 ns for H^(+),1.50 ns for Li^(+),1.70 ns for O^(8+),1.56 ns forαparticles,and 1.09 ns forβparticles.Visible differences in the excitation time spectra curves were observed.Using the conventional time-domain or frequency-domain waveform discrimination techniques,waveform discrimination of 14.9 Me V neutrons and secondary gamma rays generated by the CPNG-6 device based on GZO scintillation was successfully implemented.The neutron signal constituted 77.93%of the total,indicating that GZO exhibited superior neutron/gamma discrimination sensitivity compared with that of a commercial stilbene crystal.Using the neutron/gamma screening outcomes,we reconstructed the voltage pulse height,charge height,and neutron multiplication time spectra of the pulsed neutron radiation field.The reconstructed neutron multiplication time spectrum exhibited a deviation of less than 3%relative to the result obtained using a commercial stilbene scintillator.This is the first report in the open literature on the neutron/gamma discrimination and reconstruction of Zn O pulsed radiation-field information.展开更多
This study reports on the adsorption efficiency of a natural iron oxide from Mballam-Cameroon in comparison with synthesized goethite to simulta-neously remove cobalt and nickel ions from aqueous solutions. Chemical a...This study reports on the adsorption efficiency of a natural iron oxide from Mballam-Cameroon in comparison with synthesized goethite to simulta-neously remove cobalt and nickel ions from aqueous solutions. Chemical analysis on the natural iron oxide sample revealed iron as the main element and hematite (58.52%) goethite (19.42%), kaolinite (12.69%) and quartz (7.79%) as the component phases in the iron oxide sample. The iron oxide was found to be microporous (BET surface area 43.27 m2/g) with fairly spherical polydisperse particles. Results show maximum absorption for Co(II) and Ni(II) ions for both adsorbents occurred at an equilibrium contact time of 80 mins, dose rate of 0.1 g/L, and pH = 7. Goethite was slightly more efficient at removing target metal ions with maximal adsorbed quantities at 117.8 mg/g of Co(II) and 100.6 mg/g of Ni(II), and 103.9 mg/g of Co(II) and 85.2 mg/g of Ni(II) ions for natural iron oxide. Equilibrium modelling presented the Freundlich isotherm as the best fit model for both adsorbents and metal ions, indicating heterogeneity of the surface binding sites during adsorption. The pseudo-second order kinetic model was the best-fit model, indicating chemical adsorption between the adsorbent surface and metal ions, hence a good correlation between equilibrium and kinetics. The findings indicate that the efficacy of the natural iron oxide from Mballam is almost equivalent to that of synthetic goethite, validating its applicability for the simultaneous removal of cobalt and nickel ions from aqueous solution.展开更多
With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4...With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4）. The resulting g-C3N4/Vo-ZnO hybrid photocatalysts showed higher visible-light photocatalytic activity than pure Vo-ZnO and g-C3N4. The hybrid photocatalyst with a g-C3N4 content of 1 wt% exhibited the highest photocatalytic degradation activity under visible-light irradiation（λ≥ 400 nm）. In addition,the g-C3N4/Vo-ZnO photocatalyst was not deactivated after five cycles of methyl orange degradation,indicating that it is stable under light irradiation. Finally,a Z-scheme mechanism for the enhanced photocatalytic activity and stability of the g-C3N4/Vo-ZnO hybrid photocatalyst was proposed. The fast charge separation and transport within the g-C3N4/Vo-ZnO hybrid photocatalyst were attributed as the origins of its enhanced photocatalytic performance.展开更多
The species of arsenic in secondary zinc oxide generated from fuming furnace were investigated. The results revealed that there are mainly three types of secondary zinc oxide based on three arsenic species. The main p...The species of arsenic in secondary zinc oxide generated from fuming furnace were investigated. The results revealed that there are mainly three types of secondary zinc oxide based on three arsenic species. The main phase of As is As2O3 in type Ⅰ, zinc arsenite （Zn（AsO2）2） in type Ⅱ and lead arsenate （Pb（As206）, Pb4As2O9） in type Ⅲ, respectively. Selective leaching of zinc oxide of type Ⅱ was carried out. The leaching rate of As kept at 65%-70% with 30 g/L NaOH and L/S ratio of 3 at 20 ℃ for 1 h, while the losses of Pb and Zn were both below 1%.展开更多
A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%,...A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction （MSR）, was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible.展开更多
Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leachi...Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5：1.展开更多
The selective recovery of lead from the zinc oxide dust using an alkaline Na2EDTA solution was investigated. The effects of temperature, leaching time, Na2EDTA concentration and initial NaOH concentration on the leach...The selective recovery of lead from the zinc oxide dust using an alkaline Na2EDTA solution was investigated. The effects of temperature, leaching time, Na2EDTA concentration and initial NaOH concentration on the leaching rates of lead and zinc were studied. The following optimized leaching conditions were obtained： liquid-to-solid ratio 5：1 mL/g, stirring speed 650 r/min, Na2EDTA concentration 0.12 mol/L, initial NaOH concentration 0.5 mol/L, leaching temperature 70 ℃, leaching time 120 min. Under the optimized conditions, the average leaching rates of lead, zinc, fluoride and chloride are 89.92%, 0.94%, 62.84% and 90.02%, respectively. The filtrate was used to electrowin lead powders. The average current efficiency of electrowinning is about 93% and lead content is higher than 98% under the conditions of temperature of 60 ℃, current density of 200 A/m2, H3PO4 concentration of 1.5 g/L, and lead ion concentration of above 5 g/L. The consumption of Na2EDTA and the direct current are about respectively 0.218 kg and 0.958 kW·h for per kilogram of lead powder.展开更多
Microwave was applied to roasting the zinc oxide fume obtained from fuming furnace for the removal of F and Cl. The effects of important parameters, such as roasting temperature, holding time and stirring speed, were ...Microwave was applied to roasting the zinc oxide fume obtained from fuming furnace for the removal of F and Cl. The effects of important parameters, such as roasting temperature, holding time and stirring speed, were investigated and the process conditions were optimized using response surface methodology (RSM). The results show that the effects of roasting temperature and holding time on the removal rate of F and Cl are the most significant, and the effect of stirring speed is the second. The defluorination rate reaches 92.6% while the dechlorination rate reaches 90.2%, under the process conditions of roasting temperature of 700 °C, holding time of 80 min and stirring speed of 120 r/min. The results indicate that the removal of F and Cl from fuming furnace production of zinc oxide fumes using microwave roasting process is feasible and reliable.展开更多
Cavity perturbation method was used to determine the dielectric properties （ε′,ε″, and tanδ） of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption prope...Cavity perturbation method was used to determine the dielectric properties （ε′,ε″, and tanδ） of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption properties of zinc oxide dust and the feasibility of microwave roasting zinc oxide dust to remove fluorine and chlorine. The dielectric constant, dielectric loss, and loss tangent were proportional to the apparent density of zinc oxide dust. The effects of sample mass and microwave power on the temperature increase characteristics under the microwave field were also studied. The results show that the apparent heating rate of the zinc oxide dust increases with the increase in microwave roasting power and decreases with the increase in the sample mass. The temperature of the samples reaches approximately 800 ＆#176;C after microwave treatment for 8 min, which indicates that the zinc oxide dust has strong microwave-absorption ability.展开更多
A zinc oxide ZnO field emitter-based backlight unit for liquid crystal display with a gated structure is fabricated by screen-printing processes.The measured anode field emission current density reaches 0.62 mA/cm2 wh...A zinc oxide ZnO field emitter-based backlight unit for liquid crystal display with a gated structure is fabricated by screen-printing processes.The measured anode field emission current density reaches 0.62 mA/cm2 when the applied gate voltage is 570 V.Part of the anode current is contributed by the secondary electron emission which is excited from the MgO layer inside the gate apertures on the gate plate. The average emission current density and luminance are 0.47 mA/cm2 and 1 250 cd/m2 respectively with a fluctuation of about 10% during the 1 000 min measurement.By a finite element method calculation the gated structure shows a good electron beam focusing property. The driving performance of the backlight unit is characterized by SPICE simulation tools and measured by the oscilloscope. Stable field emission line-by-line scanning and fast response characteristics of the backlight unit indicate its promising application in the liquid crystal displays.展开更多
Aluminum doped zinc oxide （AZO）, as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that t...Aluminum doped zinc oxide （AZO）, as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that the rate performance and low-temperature performance of LiFePO4 are greatly improved by the surface treatment. Even at 20C rate, the discharge specific capacity of 100.9 mA.h/g was obtained by the AZO-coated LiFePO4 at room temperature. At -20 ℃, the discharge specific capacity at 0.2C for un-coated LiFePO4 and the coated one are 50.3 mA.h/g and 119.4 mA.h/g, respectively. It should be attributed to the electrically conductive AZO-coating which increases the electronic conductivity of LiFePO4. Furthermore, the surface-coating increases the tap-density of LiFePO4. The results indicate that the AZO-coated LiFePO4 is a good candidate of cathode material for applying in lithium power batteries.展开更多
Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency （RF） msgnetron sputtering at room temperature, The...Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency （RF） msgnetron sputtering at room temperature, The RF power is varied from 75 to 150 W. At first the crystallinity and conductivity of the film are improved and then both of them show deterioration with the increase of the RF power, The lowest resistivity achieved is 2.07 × 10^-3Ωcm at an RF power of 100W with a Hall mobility of 16cm^2V^-1s^-1 and a carrier concentration of 1.95 × 10^20 cm^-3. The films obtained are polycryetalline with a hexagonal structure and a preferred orientation along the c-axis, All the films have a high transmittance of approximately 92% in the visible range. The optical band gap is about 3.33 eV for the films deposited at different RF powers.展开更多
Abstract： Trivalent europium doped zinc oxide （ZnO：Eu3＋） nanocrystals were synthesized via room temperature chemical co-pre- cipitation and they were systematically characterized by means of X-ray diffraction （...Abstract： Trivalent europium doped zinc oxide （ZnO：Eu3＋） nanocrystals were synthesized via room temperature chemical co-pre- cipitation and they were systematically characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and photoluminescence （PL） spectroscopy. The as-synthesized samples were found to have hexagonal wurtzite coexisted with the intermediate Zn5（OH）sC12·H2O phase, while the single hexagonal phase was facilitated due to the calcinations. The as obtained samples were broadly composed ofnanoflakes while the highly crystalline nanorods were formed due to low temperature annealing of the as-synthesized samples. The crystallite size of the nanoflakes and nanorods （40-90 nm） were extracted from the XRD pattern which was found to be consistent with scanning electron microscopy （SEM） measurements. The photoluminescence （PL） spectra of nanophosphors showed bright red and orange emissions at 618 and 594 nm respectively with efficient broad blue green emis- sion spectrum due to ZnO lattice. Further, a good energy transfer process from ZnO host to Eu3＋ was observed in PL emission and excitation spectra of Eu3＋ doped ZnO ions. In all, the present nanophosphors were found to have great potentiality for bio-appli- cations.展开更多
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(61774140).
文摘ZnO thin films with varying Ta concentrations were fabricated through magnetron sputtering.The crystallinity and surface morphology of the ZnO films are significantly influenced by the incorporation of Ta,as evidenced by the X-ray diffraction and scanning electron microscopy results.The lattice constants,as determined by X-ray diffraction,contradict the disparity in Ta and Zn ion radii,which is attributed to the impact of interstitial defects.This inconsistency introduces variations in carrier concentration in this experiment compared with prior studies.Subsequent exploration of the luminescent characteristics and emission mechanism of defect levels in Ta-doped ZnO films was conducted through photoluminescence.Furthermore,the factors influencing the bandgap are discussed.
文摘Here,a preparation of stable,non-toxic,transparent,high performance zinc oxide thin-film semiconductor via thermal processing of composite system of zinc source solution filled zinc oxide nanoparticles layer was reported.The zinc oxide nanocrystals synthesized through the thermolysis of Zn-oleate complex in organic solvent medium were first deposited on the ATO/ITO/glass substrate and treated by annealing,then the zinc source solution was deposited on the zinc oxide nanoparticle layer to form precursor thin film by spin-coating process.The thin film transistor with well-controlled and densely packed nanocrystals in zinc oxide semiconductor layer was obtained by thermal annealing the system of precursor film coated ATO/ITO/glass substrate.By optimizing the fabrication conditions,the fabricated thin film transistors exhibited superior field-effect property and carrier mobility property,their saturation mobility reached 2.17 cm^(2)·V^(-1)·s^(-1),which was more than twice as high compared to the transistor devices coated only by zinc oxide nanoparticles.Our method of fabricating zinc oxide thin film transistors was simple,high efficiency,and feasible for the batch production with low cost.
文摘Objective:To examine the protective effects of green-synthesized zinc oxide nanoparticles with Berberis vulgaris L.fruit aqueous extract(BVZnONPs)on cyclophosphamide(CP)-induced nephrotoxicity in Wistar rats.Methods:35 Adult male Wistar rats were divided into 5 groups:normal,BVZnONPs(20 mg/kg),CP(100 mg/kg),and 2 co-treatment groups receiving CP with BVZnONPs(10 and 20 mg/kg).All treatments were administered intraperitoneally for 28 days.Serum levels of antioxidant enzymes(catalase,superoxide dismutase,glutathione peroxidase,nitric oxide)and kidney function parameters(creatinine,total protein,blood urea nitrogen)were measured.The expressions of p53 and Bcl-2 proteins were assessed via immunohistochemical assay while kidney volume and substructures were estimated stereologically.Results:CP induced nephrotoxicity with significant increases(P<0.05)in nitric oxide,creatinine,and blood urea nitrogen levels,and decreases(P<0.05)in catalase,superoxide dismutase,and glutathione peroxidase levels.It also increased p53 protein expression and decreased Bcl-2 protein expression.Treatment with BVZnONPs significantly increased(P<0.05)antioxidant enzyme levels and decreased nitric oxide levels in the 20 mg/kg group compared to CP.Blood urea nitrogen and creatinine levels were significantly reduced in the BVZnONPs-treated groups,with greater effects at 20 mg/kg.However,total protein serum levels were not significant(P>0.05)in the BVZnONPs-treated groups compared to CP.Conclusions:These findings suggest that BVZnONPs can mitigate CP-induced nephrotoxicity,likely due to their antioxidant and anti-apoptotic properties,though longer treatment duration may be necessary for tissue-level improvements.
基金supported by the National Research Centre,Dokki,Cairo,Egypt project#13050302.
文摘Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles(Cin@CSNPs)against oxidative damage and genotoxicity of ZnO-NPs in mice.ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L.Cin was extracted from cinnamon essential oil,and was loaded into chitosan nanoparticle(Cin@CSNPs).Both ZnO-NPs,Cin@CSNPs and CSNPs were characterized.The in vitro release of Cin@CSNPs was determined.In the biological study,6 groups of male BALB/c mice were treated by gavage for 3 weeks as follows,control group,the group received ZnO-NPs(25 mg/kg b.w),the groups received Cin@CSNPs at low dose(50 mg/kg b.w)or high dose(100 mg/kg b.w),and the groups received ZnO-NPs plus Cin@CSNPs at the 2 tested doses.Blood and tissue samples were collected for different biochemical,genetical and histological studies.The particle size of ZnO-NPs,CSNPs,and Cin@CSNPs were(20.78±2.60),(170.0±3.7),and(218.23±2.90)nm,andξ-potential were(32.7±4.6),(8.32±0.27)and(4.80±0.21)mV,respectively.ZnO-NPs disturbed the biochemical and oxidative stress indices,AFP,CEA,TNF-α,chromosomal aberrations in somatic and germ cells,and sperm abnormality along with severe pathological changes in the hepatic,renal,and testicular tissues.Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent.Therefore,the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity,and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.
基金the National Natural Science Foundation of China （Nos. 40471070 and 40403009） the Key Project of the Ministry of Education of China （No. 105122） for financial supports to this research.
文摘Oxidation of As^Ⅲ by three types of manganese oxide minerals affected by goethite was investigated by chemical analysis, equilibrium redox, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. Three synthesized Mn oxide minerals of different types, birnessite, todorokite, and hausmannite, could actively oxidize As^Ⅲ to Asv, and greatly varied in their oxidation ability. Layer structured birnessite exhibited the highest capacity of As^Ⅲ oxidation, followed by the tunnel structured todorokite. Lower oxide hansmannite possessed much low capacity of As^Ⅲ oxidation, and released more Mn^2＋ than birnessite and todorokite during the oxidation. The maximum amount of Asv produced during the oxidation of As^Ⅲ by Mn oxide minerals was in the order： birnessite （480.4 mmol/kg） 〉 todorokite （279.6 mmol/kg） 〉 hansmannite （117.9 mmol/kg）. The oxidation capacity of the Mn oxide minerals was found to be relative to the composition, crystallinity, and surface properties. In the presence of goethite oxidation of As^Ⅲ by Mn oxide minerals increased, with maximum amounts of Asv being 651.0 mmol/kg for birnessite, 332.3 mmol/kg for todorokite and 159.4 mmol/kg for hansmannite. Goethite promoted As^Ⅲ oxidation on the surface of Mn oxide minerals through adsorption of the Asv produced, incurring the decrease of Asv concentration in solutions. Thus, the combined effects of the oxidation （by Mn oxide minerals）-adsorption （by goethite） lead to rapid oxidation and immobilization of As in soils and sediments and alleviation of the As^Ⅲ toxicity in the environments.
基金supported by the National Natural Science Foundation of China(No.22179109).
文摘Although the enhancement of the zinc storage performance of layered vanadium oxides can be realized by the ionic pre-intercalation strategy,it also occupies a large number of active sites and thus fails to release the full potential of vanadium oxides.Here,vanadium oxide nanobelts with sodium-poor and oxygen defect-rich were constructed by regulating the content of pre-embedded sodium ions to strike a balance between pre-embedded ions and structural stability.The introduction of trace sodium ions not only increases the spacing of vanadium oxide layers but also occupies as few active sites as possible,which provides the possibility of massive storage,rapid diffusion and stabilization of the host structure for zinc ions.Moreover,the abundant oxygen defects transform the ion transport pathway from two-dimensional to three-dimensional,which greatly improves the ion transport rate in the host phase.Due to these advantages,the synthesized vanadium oxide nanobelts exhibit remarkable electrochemical properties,and this work provides a new idea for the design of structurally stable layered vanadium oxides with excellent properties.
基金supported by the National Natural Science Foundation of China(Nos.12205370,62204198,12305205,and 12105230)Young Talents Promotion Program of Shaanxi Provincial Science and Technology Association(No.20220514)。
文摘Doping with Ga effectively enhances the crystal quality and optical detection efficiency of zinc oxide(Zn O)single crystals,which has attracted considerable research interest in radiation detection.The application of Zn O:Ga(GZO)in nuclear energy is particularly significant and fascinating at the fundamental level,enabling neutron/gamma discrimination while preserving the response time properties of the single crystal in sub-nanoseconds,maximizing the effective counting rate of the pulsed radiation field.In this study,the single-particle waveform discrimination characteristics of GZO were evaluated for five charged particles(α,β,H^(+),Li^(+),and O^(8+)and two prevalent uncharged particles(neutrons and gamma rays).Based on the timecorrelation single-photon counting(TCSPC)method,the luminescence decay time constants of the charged particles in the GZO crystal were determined as follows:1.21 ns for H^(+),1.50 ns for Li^(+),1.70 ns for O^(8+),1.56 ns forαparticles,and 1.09 ns forβparticles.Visible differences in the excitation time spectra curves were observed.Using the conventional time-domain or frequency-domain waveform discrimination techniques,waveform discrimination of 14.9 Me V neutrons and secondary gamma rays generated by the CPNG-6 device based on GZO scintillation was successfully implemented.The neutron signal constituted 77.93%of the total,indicating that GZO exhibited superior neutron/gamma discrimination sensitivity compared with that of a commercial stilbene crystal.Using the neutron/gamma screening outcomes,we reconstructed the voltage pulse height,charge height,and neutron multiplication time spectra of the pulsed neutron radiation field.The reconstructed neutron multiplication time spectrum exhibited a deviation of less than 3%relative to the result obtained using a commercial stilbene scintillator.This is the first report in the open literature on the neutron/gamma discrimination and reconstruction of Zn O pulsed radiation-field information.
文摘This study reports on the adsorption efficiency of a natural iron oxide from Mballam-Cameroon in comparison with synthesized goethite to simulta-neously remove cobalt and nickel ions from aqueous solutions. Chemical analysis on the natural iron oxide sample revealed iron as the main element and hematite (58.52%) goethite (19.42%), kaolinite (12.69%) and quartz (7.79%) as the component phases in the iron oxide sample. The iron oxide was found to be microporous (BET surface area 43.27 m2/g) with fairly spherical polydisperse particles. Results show maximum absorption for Co(II) and Ni(II) ions for both adsorbents occurred at an equilibrium contact time of 80 mins, dose rate of 0.1 g/L, and pH = 7. Goethite was slightly more efficient at removing target metal ions with maximal adsorbed quantities at 117.8 mg/g of Co(II) and 100.6 mg/g of Ni(II), and 103.9 mg/g of Co(II) and 85.2 mg/g of Ni(II) ions for natural iron oxide. Equilibrium modelling presented the Freundlich isotherm as the best fit model for both adsorbents and metal ions, indicating heterogeneity of the surface binding sites during adsorption. The pseudo-second order kinetic model was the best-fit model, indicating chemical adsorption between the adsorbent surface and metal ions, hence a good correlation between equilibrium and kinetics. The findings indicate that the efficacy of the natural iron oxide from Mballam is almost equivalent to that of synthetic goethite, validating its applicability for the simultaneous removal of cobalt and nickel ions from aqueous solution.
基金supported by the National Basic Research Program of China(2011CB933700)the National Natural Science Foundation of China(21271165)~~
文摘With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4）. The resulting g-C3N4/Vo-ZnO hybrid photocatalysts showed higher visible-light photocatalytic activity than pure Vo-ZnO and g-C3N4. The hybrid photocatalyst with a g-C3N4 content of 1 wt% exhibited the highest photocatalytic degradation activity under visible-light irradiation（λ≥ 400 nm）. In addition,the g-C3N4/Vo-ZnO photocatalyst was not deactivated after five cycles of methyl orange degradation,indicating that it is stable under light irradiation. Finally,a Z-scheme mechanism for the enhanced photocatalytic activity and stability of the g-C3N4/Vo-ZnO hybrid photocatalyst was proposed. The fast charge separation and transport within the g-C3N4/Vo-ZnO hybrid photocatalyst were attributed as the origins of its enhanced photocatalytic performance.
基金Project (50874121) supported by the National Natural Science Foundation of China
文摘The species of arsenic in secondary zinc oxide generated from fuming furnace were investigated. The results revealed that there are mainly three types of secondary zinc oxide based on three arsenic species. The main phase of As is As2O3 in type Ⅰ, zinc arsenite （Zn（AsO2）2） in type Ⅱ and lead arsenate （Pb（As206）, Pb4As2O9） in type Ⅲ, respectively. Selective leaching of zinc oxide of type Ⅱ was carried out. The leaching rate of As kept at 65%-70% with 30 g/L NaOH and L/S ratio of 3 at 20 ℃ for 1 h, while the losses of Pb and Zn were both below 1%.
基金Project(50925417) supported by the China National Funds for Distinguished Young ScientistsProject(50830301) supported by the National Natural Science Foundation of China+1 种基金Projects(2010AA065203,2011AA061001) supported by the National High-tech Research Program of ChinaProject(NCET-10-0840) supported by the Program for New Century Excellent Talents in University,China
文摘A novel process for sulfidation of ZnO by co-grinding with sulfur and reductive additives （P, Fe, A1, and Mg） was developed. The sulfidation extent of ZnO with the addition of P, Fe, A1 or Mg can reach 85.2%, 81.6%, 96.7% and 92.6% after grinding for 4, 6, 1 and 1 h, respectively. Based on the chemical phase composition analysis and morphological characteristics of sulfidized products by XRD, SEM and TEM, a possible reaction mechanism, mechanically induced self-propagating reaction （MSR）, was proposed to explain the sulfidization reaction. In addition, the floatability of sulfidized products was investigated for the recovery of metal sulfide and ZnS can be concentrated with a high concentration ratio and concentrate grade. By using the sulfidizing process, it is expected that the recovery of zinc from the wastes or purification of heavy-metal-containing hazardous residues is technically feasible.
基金Project (2007CB613604) supported by the National Basic Research Program of China
文摘Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5：1.
基金Project (50974138) supported by the National Natural Science Foundation of ChinaProject (2010ssxt158) supported by Graduate Student Innovation Foundation of Central South University,China
文摘The selective recovery of lead from the zinc oxide dust using an alkaline Na2EDTA solution was investigated. The effects of temperature, leaching time, Na2EDTA concentration and initial NaOH concentration on the leaching rates of lead and zinc were studied. The following optimized leaching conditions were obtained： liquid-to-solid ratio 5：1 mL/g, stirring speed 650 r/min, Na2EDTA concentration 0.12 mol/L, initial NaOH concentration 0.5 mol/L, leaching temperature 70 ℃, leaching time 120 min. Under the optimized conditions, the average leaching rates of lead, zinc, fluoride and chloride are 89.92%, 0.94%, 62.84% and 90.02%, respectively. The filtrate was used to electrowin lead powders. The average current efficiency of electrowinning is about 93% and lead content is higher than 98% under the conditions of temperature of 60 ℃, current density of 200 A/m2, H3PO4 concentration of 1.5 g/L, and lead ion concentration of above 5 g/L. The consumption of Na2EDTA and the direct current are about respectively 0.218 kg and 0.958 kW·h for per kilogram of lead powder.
基金Project(51104073)supported by the National Natural Science Foundation of ChinaProject(2013AA064003)supported by the High-tech Research and Development Program of China+1 种基金Project(2014CB643404)supported by the National Basic Research Program of ChinaProject(2012HB008)supported by Yunnan Province Young Academic Technology Leader Reserve Talents,China
文摘Microwave was applied to roasting the zinc oxide fume obtained from fuming furnace for the removal of F and Cl. The effects of important parameters, such as roasting temperature, holding time and stirring speed, were investigated and the process conditions were optimized using response surface methodology (RSM). The results show that the effects of roasting temperature and holding time on the removal rate of F and Cl are the most significant, and the effect of stirring speed is the second. The defluorination rate reaches 92.6% while the dechlorination rate reaches 90.2%, under the process conditions of roasting temperature of 700 °C, holding time of 80 min and stirring speed of 120 r/min. The results indicate that the removal of F and Cl from fuming furnace production of zinc oxide fumes using microwave roasting process is feasible and reliable.
基金Project(51104073)supported by the National Natural Science Foundation of ChinaProject(2014CB643404)supported by the National Basic Research Program of China+1 种基金Project(2013AA064003)supported by the Hi-tech Research and Development Program of ChinaProject(2012HB008)supported by the Yunnan Provincial Young Academic Technology Leader Reserve Talents,China
文摘Cavity perturbation method was used to determine the dielectric properties （ε′,ε″, and tanδ） of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption properties of zinc oxide dust and the feasibility of microwave roasting zinc oxide dust to remove fluorine and chlorine. The dielectric constant, dielectric loss, and loss tangent were proportional to the apparent density of zinc oxide dust. The effects of sample mass and microwave power on the temperature increase characteristics under the microwave field were also studied. The results show that the apparent heating rate of the zinc oxide dust increases with the increase in microwave roasting power and decreases with the increase in the sample mass. The temperature of the samples reaches approximately 800 ＆#176;C after microwave treatment for 8 min, which indicates that the zinc oxide dust has strong microwave-absorption ability.
基金The National Basic Research Program of China(973 Program)(No.2013CB328803)the National Natural Science Foundation of China(No.51002031)+1 种基金the Ph.D.Programs Foundation of Ministry of Education of China(No.20100092120022)the National High Technology Research and Development Program of China(863 Program)(No.2012AA03A302,2013AA011004)
文摘A zinc oxide ZnO field emitter-based backlight unit for liquid crystal display with a gated structure is fabricated by screen-printing processes.The measured anode field emission current density reaches 0.62 mA/cm2 when the applied gate voltage is 570 V.Part of the anode current is contributed by the secondary electron emission which is excited from the MgO layer inside the gate apertures on the gate plate. The average emission current density and luminance are 0.47 mA/cm2 and 1 250 cd/m2 respectively with a fluctuation of about 10% during the 1 000 min measurement.By a finite element method calculation the gated structure shows a good electron beam focusing property. The driving performance of the backlight unit is characterized by SPICE simulation tools and measured by the oscilloscope. Stable field emission line-by-line scanning and fast response characteristics of the backlight unit indicate its promising application in the liquid crystal displays.
文摘Aluminum doped zinc oxide （AZO）, as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that the rate performance and low-temperature performance of LiFePO4 are greatly improved by the surface treatment. Even at 20C rate, the discharge specific capacity of 100.9 mA.h/g was obtained by the AZO-coated LiFePO4 at room temperature. At -20 ℃, the discharge specific capacity at 0.2C for un-coated LiFePO4 and the coated one are 50.3 mA.h/g and 119.4 mA.h/g, respectively. It should be attributed to the electrically conductive AZO-coating which increases the electronic conductivity of LiFePO4. Furthermore, the surface-coating increases the tap-density of LiFePO4. The results indicate that the AZO-coated LiFePO4 is a good candidate of cathode material for applying in lithium power batteries.
基金Project supported by the National Key Basic Research and Development Programme of China （Grant No 2001CB610504） and the National Natural Science Foundation of China （Grant Nos 60576039 and 10374060）.Acknowledgments We thank Dr Wang Zhuo and Dr Yang ChangHong for their assistance in the experiment.
文摘Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency （RF） msgnetron sputtering at room temperature, The RF power is varied from 75 to 150 W. At first the crystallinity and conductivity of the film are improved and then both of them show deterioration with the increase of the RF power, The lowest resistivity achieved is 2.07 × 10^-3Ωcm at an RF power of 100W with a Hall mobility of 16cm^2V^-1s^-1 and a carrier concentration of 1.95 × 10^20 cm^-3. The films obtained are polycryetalline with a hexagonal structure and a preferred orientation along the c-axis, All the films have a high transmittance of approximately 92% in the visible range. The optical band gap is about 3.33 eV for the films deposited at different RF powers.
文摘Abstract： Trivalent europium doped zinc oxide （ZnO：Eu3＋） nanocrystals were synthesized via room temperature chemical co-pre- cipitation and they were systematically characterized by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and photoluminescence （PL） spectroscopy. The as-synthesized samples were found to have hexagonal wurtzite coexisted with the intermediate Zn5（OH）sC12·H2O phase, while the single hexagonal phase was facilitated due to the calcinations. The as obtained samples were broadly composed ofnanoflakes while the highly crystalline nanorods were formed due to low temperature annealing of the as-synthesized samples. The crystallite size of the nanoflakes and nanorods （40-90 nm） were extracted from the XRD pattern which was found to be consistent with scanning electron microscopy （SEM） measurements. The photoluminescence （PL） spectra of nanophosphors showed bright red and orange emissions at 618 and 594 nm respectively with efficient broad blue green emis- sion spectrum due to ZnO lattice. Further, a good energy transfer process from ZnO host to Eu3＋ was observed in PL emission and excitation spectra of Eu3＋ doped ZnO ions. In all, the present nanophosphors were found to have great potentiality for bio-appli- cations.
