Although carbon coating can improve the cycle life of anode for alkaline Zn batteries, the specific capacity reported is still lower compared with nanosized ZnO. Herein, carbon-coated nanosized ZnO(nano-ZnO@C) was syn...Although carbon coating can improve the cycle life of anode for alkaline Zn batteries, the specific capacity reported is still lower compared with nanosized ZnO. Herein, carbon-coated nanosized ZnO(nano-ZnO@C) was synthesized by one-step heat treatment from a gel precursor in N2. Commercial ZnO and homemade ZnO prepared similarly in air atmosphere were studied for comparison. Structure analysis displayed that both nano-ZnO@C and homemade ZnO had a porous hierarchical agglomerated architecture produced from primary nanoparticles with a diameter of approximately 100 nm as building blocks. Electrochemical performance measurements showed that nano-ZnO@C displayed the highest electrochemical activity, the lowest electrode resistance, the highest discharge capacity(622 m A·h/g), and the best cyclic stability. These properties were due to the combination of nanosized ZnO and the physical capping of carbon, which maintained the high utilization efficiency of nano-ZnO, and simultaneously prevented dendrite growth and densification of the anode.展开更多
Nano-ZnO particle was produced by evaporating zinc powders in air at air flow-rate from 0.2 to 0.6m3/h. Nano-ZnO particles was formed by the oxidation of the evaporated zinc vapor. X-ray diffraction shows the powders ...Nano-ZnO particle was produced by evaporating zinc powders in air at air flow-rate from 0.2 to 0.6m3/h. Nano-ZnO particles was formed by the oxidation of the evaporated zinc vapor. X-ray diffraction shows the powders to be ZnO with lattice parameters of a=0.3249nm and c=0.5205nm. The particle size is dependent upon the transit time from the source to the collection area. The size of particles was ranged between 81 to 103nm. The average density resulted was 4.865g/cm3. Normal ZnO and nano-ZnO were investigated to use them in aluminum metallurgy as an inert anode material. A certain amount of both oxides were molded subsequently inserted to the molten cryolite-aluminum oxide to investigate the corrosive behavior of both oxides. When the sintering temperature increased up to 1300℃, the weight loss ratio rose to 5.01%-7.33% and up to 7.67%-10.18% for nano-ZnO and normal ZnO, respectively. However, when the samples in the molten cryolite aluminum oxide were put for long time, the corrosive rate was found to be higher. It was found that the corrosive loss weight ratio of nano-ZnO anode was much lower than the normal one made from ordinary-ZnO providing that the nano-ZnO is more possible to be use inert anode material.展开更多
Development of new materials using composite materials has been much interest. XLPE is a kind of power cable in high voltage insulation. Recently research for cable insulating material has shown that nano-size filler ...Development of new materials using composite materials has been much interest. XLPE is a kind of power cable in high voltage insulation. Recently research for cable insulating material has shown that nano-size filler added to XLPE is electrically and physically stable. In this paper, Impulse strength was measured in XLPE that composite by adding na-no-ZnO with different mass proportions. There is positive and negative impulse voltage. However, there is no differ-ence between them on the film specimen. Therefore we tested only positive voltage. In order to understand temperature properties of XLPE nanocomposite sample, experiment of impulse breakdown strength were measured at room temper-ature and maximum allowable temperature (90℃). From this result, it can be considered that the breakdown strength of addition of展开更多
The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation.IR,XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its des...The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation.IR,XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its desulfurization activities are improved greatly.When calcined at 270 ℃,Ce distributes evenly on the ZnO particle surface as amorphous state oxides,and the amorphous ZnO·H2O also exists;when the calcining temperature is 570 ℃,the crystal CeO2 separates out and the amorphous structure of zinc oxide disappears,at the same time,the crystal is perfect and its size increases,but the desulfurization activities decrease.The desulfurization product of nano-ZnO modified with Ce was analyzed with XPS.The results show that the adsorption compound of HS,S and ZnS exists on the surface of the desulfurizer.展开更多
In this work, microarc oxidation(MAO) technology was used to form oxide ceramic coating on the surface of aluminum alloy. The combined additives nano-TiOand nano-ZnO were added into the silicate electrolyte, and the e...In this work, microarc oxidation(MAO) technology was used to form oxide ceramic coating on the surface of aluminum alloy. The combined additives nano-TiOand nano-ZnO were added into the silicate electrolyte, and the effect of the compound nano-additive on microstructure and properties of MAO coating was investigated. The results show that compared with those of the nano-additive-free coating formed on aluminum alloy, the thickness, hardness, abrasion resistance and corrosion resistance of the nano-additive-containing coating are obviously improved. The surface of coating with nanoadditive becomes smooth, dense, and there are less porosities and microcracks. Moreover, the content of crystal phase a-AlOand y-AlOincreases visibly on the nano-additive-containing MAO coatings, and new phases AlTi and ZnTiare detected in the coatings, which are mainly contributed to the excellent corrosion resistance and abrasion resistance of the film. When the contents of nano-TiOand nano-ZnO are, respectively, 4 and 2 g-L, the film has better comprehensive performance, the thickness and hardness of the film could reach 52 μm and HV 692,respectively.展开更多
The toxicity of nano-materials has received increasing attention in recent years. Nevertheless, relatively few studies have focused on their oceanic distributions and toxicities. In this study, we assessed nano-ZnO to...The toxicity of nano-materials has received increasing attention in recent years. Nevertheless, relatively few studies have focused on their oceanic distributions and toxicities. In this study, we assessed nano-ZnO toxicity in marine organisms using the yellowstriped goby （Mugilogobius chulae）. The relative differences in nano-ZnO dissolution and dispersal in seawater and fresh water were also investigated. The effects of nano-ZnO on embryonic development, deformity, hatching, mortality, and histopathology were analyzed. In addition, the effects of the Zn2＋ concentration on M. chulae hatching and mortality were compared. The results showed that nano-ZnO had higher solubility in seawater than in fresh water. Nano-ZnO significantly inhibited hatching. By the fifth day of exposure, the LC50 of nano-ZnO was 45.40 mg/L, and the mortality rate spiked. Hatching inhibition and lethality were dose-dependent over a range of 1-25 mg/L nano-ZnO. Zn2＋ inhibited hatching and increased lethality, but its effects were weaker than those of nano-ZnO at the same concentrations. Nano-ZnO also induced spinal bending, oedema, hypoplasia, and other deformities in M. chulae embryos and larvae. Histopathology revealed vacuolar degeneration, hepatocyte and enterocyte enlargement, and morphological abnormalities of the vertebrae. Therefore, nano-ZnO caused malformations in M. chulae by affecting embryonic growth and development. We conclude that nano-ZnO toxicity in seawater was significantly positively correlated with the associated Zn2＋ concentration and sedimentary behaviour. The toxicity of nano-ZnO was cumulative and showed a critical point, beyond which embryonic and developmental toxicity in marine fish was observed.展开更多
Enhanced ozonation degradation of atrazine（ATZ） with nano-ZnO（nZnO） as catalyst and the influences of the operational parameters have been investigated through semi-continuous experiments in this study. The result...Enhanced ozonation degradation of atrazine（ATZ） with nano-ZnO（nZnO） as catalyst and the influences of the operational parameters have been investigated through semi-continuous experiments in this study. The results demonstrated that the combination of ozone（O3） and nZnO showed an obvious synergetic effect and the ATZ degradation conformed to pseudo-first-order kinetics. An improvement of ATZ degradation efficiency by 41.8% and pseudo-first-order rate constant by more than a factor of four was obtained in the O3/nZnO process after 5 min of reaction compared to O3 alone. Meanwhile, the degradation efficiency of ATZ was gradually enhanced with increasing nZnO dosage and initial pH in the range from 3.0 to 8.0, and a higher amount of ATZ was degraded when the initial concentration of ATZ rose from 0.5 to 5 mg/L. Additionally, sulfate ion, chloride ion, nitrate ion and low concentrations of humic acid substances led to enhancement of the ATZ degradation. The notable decrease of ATZ removal efficiency observed in the presence of radical scavengers and the results of free radical tests indicated thatUOH is the dominant active radical species. The mechanism investigation demonstrated that the enhancement effect could be attributed to the introduction of nZnO,which could promote the utilization of O3, enhance the formation of superoxide radical, and further accelerate the production of hydrogen peroxide and the generation of OH/O2-.展开更多
Nano-ZnO thin films composed of nanoparticles with sizes of 10-16 nm on silicon substrates at low temperature were prepared by sol-gel method.By placing the nano-ZnO thin films at room temperature or annealing at 100&...Nano-ZnO thin films composed of nanoparticles with sizes of 10-16 nm on silicon substrates at low temperature were prepared by sol-gel method.By placing the nano-ZnO thin films at room temperature or annealing at 100°C in air for 10 h intermittently,within a total 70 h annealing time,the evolution of PL spectra of the nano-ZnO thin films were studied in detail.As the annealing time increases,the PL peaks shift from violet to blue and green bands.The PL peaks at violet and blue bands decrease with the annealing time,but the PL peaks at green band are opposite.The PL spectra are related to the defects in the nano-ZnO thin films.The PL peaks positioned at 430 nm are mainly related to defects of zinc interstatials(Zni),oxygen vacancies and(Vo);the ones at 420 nm to oxygen interstitials(Oi),Zinc vacancies(Vzn),Zni ;and the ones at 468 nm to Vzn,Zni,and charged oxygen interstatials(Vo+).The green luminescence is related to Oi,Vo and Zni.The evolutions of PL spectra and the defects are also related to the concentrations of Zn in the thin films,the thicknesses of the films and the annealing time.For the films with 0.5 M and 1.0 M Zn concentrations,after 20 h and 30 h annealing in air at 100°C,respectively,either placing them in air at room temperature or continuing anneal in air at 100°C,the PL spectra are stable.Under the low temperature annealing,Zni decreases with the annealing time,and Oi increases.Sufficient Oi favors to keep the nano-ZnO thin films stable.This result is important to nano-ZnO thin films as electron transport layers in inverted or tandem organic solar cells.展开更多
基金Project(51674301) supported by the National Natural Science Foundation of China
文摘Although carbon coating can improve the cycle life of anode for alkaline Zn batteries, the specific capacity reported is still lower compared with nanosized ZnO. Herein, carbon-coated nanosized ZnO(nano-ZnO@C) was synthesized by one-step heat treatment from a gel precursor in N2. Commercial ZnO and homemade ZnO prepared similarly in air atmosphere were studied for comparison. Structure analysis displayed that both nano-ZnO@C and homemade ZnO had a porous hierarchical agglomerated architecture produced from primary nanoparticles with a diameter of approximately 100 nm as building blocks. Electrochemical performance measurements showed that nano-ZnO@C displayed the highest electrochemical activity, the lowest electrode resistance, the highest discharge capacity(622 m A·h/g), and the best cyclic stability. These properties were due to the combination of nanosized ZnO and the physical capping of carbon, which maintained the high utilization efficiency of nano-ZnO, and simultaneously prevented dendrite growth and densification of the anode.
文摘Nano-ZnO particle was produced by evaporating zinc powders in air at air flow-rate from 0.2 to 0.6m3/h. Nano-ZnO particles was formed by the oxidation of the evaporated zinc vapor. X-ray diffraction shows the powders to be ZnO with lattice parameters of a=0.3249nm and c=0.5205nm. The particle size is dependent upon the transit time from the source to the collection area. The size of particles was ranged between 81 to 103nm. The average density resulted was 4.865g/cm3. Normal ZnO and nano-ZnO were investigated to use them in aluminum metallurgy as an inert anode material. A certain amount of both oxides were molded subsequently inserted to the molten cryolite-aluminum oxide to investigate the corrosive behavior of both oxides. When the sintering temperature increased up to 1300℃, the weight loss ratio rose to 5.01%-7.33% and up to 7.67%-10.18% for nano-ZnO and normal ZnO, respectively. However, when the samples in the molten cryolite aluminum oxide were put for long time, the corrosive rate was found to be higher. It was found that the corrosive loss weight ratio of nano-ZnO anode was much lower than the normal one made from ordinary-ZnO providing that the nano-ZnO is more possible to be use inert anode material.
文摘Development of new materials using composite materials has been much interest. XLPE is a kind of power cable in high voltage insulation. Recently research for cable insulating material has shown that nano-size filler added to XLPE is electrically and physically stable. In this paper, Impulse strength was measured in XLPE that composite by adding na-no-ZnO with different mass proportions. There is positive and negative impulse voltage. However, there is no differ-ence between them on the film specimen. Therefore we tested only positive voltage. In order to understand temperature properties of XLPE nanocomposite sample, experiment of impulse breakdown strength were measured at room temper-ature and maximum allowable temperature (90℃). From this result, it can be considered that the breakdown strength of addition of
基金the National Natural Science Foundation of China(Grant No.50478026)the Science Foundation for Young Scientists of Harbin University of Science and Technology(Grant No.2008XQJZ039)
文摘The compound nano-ZnO modified with Ce was prepared by homogeneous precipitation.IR,XRD and dynamic experiments show that the crystal size of nano-ZnO desulfurizer is decreased after being modified with Ce and its desulfurization activities are improved greatly.When calcined at 270 ℃,Ce distributes evenly on the ZnO particle surface as amorphous state oxides,and the amorphous ZnO·H2O also exists;when the calcining temperature is 570 ℃,the crystal CeO2 separates out and the amorphous structure of zinc oxide disappears,at the same time,the crystal is perfect and its size increases,but the desulfurization activities decrease.The desulfurization product of nano-ZnO modified with Ce was analyzed with XPS.The results show that the adsorption compound of HS,S and ZnS exists on the surface of the desulfurizer.
基金financially supported by the International Technology Cooperation Plan in Guizhou Province (No.2012-7001)
文摘In this work, microarc oxidation(MAO) technology was used to form oxide ceramic coating on the surface of aluminum alloy. The combined additives nano-TiOand nano-ZnO were added into the silicate electrolyte, and the effect of the compound nano-additive on microstructure and properties of MAO coating was investigated. The results show that compared with those of the nano-additive-free coating formed on aluminum alloy, the thickness, hardness, abrasion resistance and corrosion resistance of the nano-additive-containing coating are obviously improved. The surface of coating with nanoadditive becomes smooth, dense, and there are less porosities and microcracks. Moreover, the content of crystal phase a-AlOand y-AlOincreases visibly on the nano-additive-containing MAO coatings, and new phases AlTi and ZnTiare detected in the coatings, which are mainly contributed to the excellent corrosion resistance and abrasion resistance of the film. When the contents of nano-TiOand nano-ZnO are, respectively, 4 and 2 g-L, the film has better comprehensive performance, the thickness and hardness of the film could reach 52 μm and HV 692,respectively.
基金supported by the Science and Technology Programs of Guangdong Province(Nos.2015A020215031,2013B020600007,and 2012B050200002)supported by the National Key Technologies R&D Program of China(No.2015BAI09B05)
文摘The toxicity of nano-materials has received increasing attention in recent years. Nevertheless, relatively few studies have focused on their oceanic distributions and toxicities. In this study, we assessed nano-ZnO toxicity in marine organisms using the yellowstriped goby （Mugilogobius chulae）. The relative differences in nano-ZnO dissolution and dispersal in seawater and fresh water were also investigated. The effects of nano-ZnO on embryonic development, deformity, hatching, mortality, and histopathology were analyzed. In addition, the effects of the Zn2＋ concentration on M. chulae hatching and mortality were compared. The results showed that nano-ZnO had higher solubility in seawater than in fresh water. Nano-ZnO significantly inhibited hatching. By the fifth day of exposure, the LC50 of nano-ZnO was 45.40 mg/L, and the mortality rate spiked. Hatching inhibition and lethality were dose-dependent over a range of 1-25 mg/L nano-ZnO. Zn2＋ inhibited hatching and increased lethality, but its effects were weaker than those of nano-ZnO at the same concentrations. Nano-ZnO also induced spinal bending, oedema, hypoplasia, and other deformities in M. chulae embryos and larvae. Histopathology revealed vacuolar degeneration, hepatocyte and enterocyte enlargement, and morphological abnormalities of the vertebrae. Therefore, nano-ZnO caused malformations in M. chulae by affecting embryonic growth and development. We conclude that nano-ZnO toxicity in seawater was significantly positively correlated with the associated Zn2＋ concentration and sedimentary behaviour. The toxicity of nano-ZnO was cumulative and showed a critical point, beyond which embryonic and developmental toxicity in marine fish was observed.
基金supported by the state supported project funds for researchdemonstration on the key technology for clean production in textile printing and dyeing (2014BAC13B02)
文摘Enhanced ozonation degradation of atrazine（ATZ） with nano-ZnO（nZnO） as catalyst and the influences of the operational parameters have been investigated through semi-continuous experiments in this study. The results demonstrated that the combination of ozone（O3） and nZnO showed an obvious synergetic effect and the ATZ degradation conformed to pseudo-first-order kinetics. An improvement of ATZ degradation efficiency by 41.8% and pseudo-first-order rate constant by more than a factor of four was obtained in the O3/nZnO process after 5 min of reaction compared to O3 alone. Meanwhile, the degradation efficiency of ATZ was gradually enhanced with increasing nZnO dosage and initial pH in the range from 3.0 to 8.0, and a higher amount of ATZ was degraded when the initial concentration of ATZ rose from 0.5 to 5 mg/L. Additionally, sulfate ion, chloride ion, nitrate ion and low concentrations of humic acid substances led to enhancement of the ATZ degradation. The notable decrease of ATZ removal efficiency observed in the presence of radical scavengers and the results of free radical tests indicated thatUOH is the dominant active radical species. The mechanism investigation demonstrated that the enhancement effect could be attributed to the introduction of nZnO,which could promote the utilization of O3, enhance the formation of superoxide radical, and further accelerate the production of hydrogen peroxide and the generation of OH/O2-.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41172110,61107090)Shandong Provincial Natural Science Foundation (Grant No. ZR2011BZ007)
文摘Nano-ZnO thin films composed of nanoparticles with sizes of 10-16 nm on silicon substrates at low temperature were prepared by sol-gel method.By placing the nano-ZnO thin films at room temperature or annealing at 100°C in air for 10 h intermittently,within a total 70 h annealing time,the evolution of PL spectra of the nano-ZnO thin films were studied in detail.As the annealing time increases,the PL peaks shift from violet to blue and green bands.The PL peaks at violet and blue bands decrease with the annealing time,but the PL peaks at green band are opposite.The PL spectra are related to the defects in the nano-ZnO thin films.The PL peaks positioned at 430 nm are mainly related to defects of zinc interstatials(Zni),oxygen vacancies and(Vo);the ones at 420 nm to oxygen interstitials(Oi),Zinc vacancies(Vzn),Zni ;and the ones at 468 nm to Vzn,Zni,and charged oxygen interstatials(Vo+).The green luminescence is related to Oi,Vo and Zni.The evolutions of PL spectra and the defects are also related to the concentrations of Zn in the thin films,the thicknesses of the films and the annealing time.For the films with 0.5 M and 1.0 M Zn concentrations,after 20 h and 30 h annealing in air at 100°C,respectively,either placing them in air at room temperature or continuing anneal in air at 100°C,the PL spectra are stable.Under the low temperature annealing,Zni decreases with the annealing time,and Oi increases.Sufficient Oi favors to keep the nano-ZnO thin films stable.This result is important to nano-ZnO thin films as electron transport layers in inverted or tandem organic solar cells.
