[Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the gr...[Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the growth kinetics and the vitamin E accumulation in wheat embryo callus cells.With the aim of getting the highest accumulation of the secondary metabolite Vitamin E,the optimal combination of copper and zinc in medium was confirmed by testing.[Result] The results showed that the production of vitamin E in B5 medium reached the highest value with 2.0 mg/mL ZnSO4·7H2O and 0.1 mg/mL CuSO4·5H2O.The fitting degrees of kinetic models of vitamin E accumulation and cell growth were 97.53% and 95.60%,respectively,which indicated good nonlinear relationships.[Conclusion] Both copper and zinc could affect the accumulation of vitamin E in wheat germ callus,and Copper showed more prominent effect than Zn.Synergism existed in low copper and zinc concentration,and the inhibitive effect enhanced with the increase of the concentrations.展开更多
Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±...Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±2434) mg kg-1, 369-831 (731±142) mg kg-1, and 429-587 (547±57) mg kg-1, respectively, in the roots, stems, and leaves. The soils supporting the growth of the species had a copper concentration ranging from 4620 to 5020 mg kg-1 and averaging 4835±262 mg kg-1, suggesting that the species could not only grow on heavily copper-contaminated soils but also accumulate extraordinarily high concentration of copper. Thus, it shows great potential in the phytoremediation of copper-contaminated soils,the restoration of mined land, geochemical prospecting, and the study of environmental pollution changes.展开更多
This study compared the accumulation of Zn2+and Cu2+in the ovaries and ova of loaches under different concentrations of Zn2+(1.00, 2.50 and 5.00 mg/L respectively) and Cu2+(0.10, 0.25 and 0.50 mg/L respectively). The ...This study compared the accumulation of Zn2+and Cu2+in the ovaries and ova of loaches under different concentrations of Zn2+(1.00, 2.50 and 5.00 mg/L respectively) and Cu2+(0.10, 0.25 and 0.50 mg/L respectively). The results showed that both Zn2+and Cu2+accumulated in the ovaries, and that the relationship between accumulation and time was linear over 20 days of exposure. The accumulation of the metals in ovaries was closely related to the concentration of exposure in the solutions(P<0.05), and was obviously affected by the time and doses. However, the Cu2+concentration was significantly higher than Zn2+(P<0.05). The development level of ova in the ovaries also correlated with the concentration and exposure period in the Zn2+and Cu2+solutions.展开更多
Cu/Al multilayers were produced by high-temperature accumulative roll bonding(ARB)methods up to three passes.To achieve a high bonding strength,prior to ARB processing,the Cu and Al sheets were heated to 350,400,450 a...Cu/Al multilayers were produced by high-temperature accumulative roll bonding(ARB)methods up to three passes.To achieve a high bonding strength,prior to ARB processing,the Cu and Al sheets were heated to 350,400,450 and 500 ℃,respectively.The mechanical properties were evaluated by tensile tests.The microstructure was examined by optical microscopy and scanning electron microscopy equipped with energy dispersive spectrometry.The ultimate tensile stress,the grain size and the thickness of diffusion layer of lamellar composites increase with rolling temperature.When the rolling temperature is 400 ℃,the laminates show the highest ductility,but the yield stress is the lowest.As the rolling temperature further increases,both the yield stress and the ultimate tensile stress increase and the ductility decreases slightly.The mechanical properties of lamellar composites processed by low and high temperature ARB are determined by grain size and the thickness of diffusion layer,respectively.展开更多
Heavy metal pollution has become a worldwide problem in aquaculture. We studied copper （Cu^2＋） accumulation and physiological responses of two red algae Gracilaria lemaneiformis and Gracilaria lichenoides from Chin...Heavy metal pollution has become a worldwide problem in aquaculture. We studied copper （Cu^2＋） accumulation and physiological responses of two red algae Gracilaria lemaneiformis and Gracilaria lichenoides from China under Cu^2＋ exposure of 0-500 μg/L in concentration. Compared with G. lemaneiformis, G. lichenoides was more capable in accumulating Cu^2＋, specifically, more Cu〉 on extracellular side （cell wall） than on intracellular side （cytoplasm） and in cell organelles （especially chloroplast, cell nucleus, mitochondria, and ribosome）. In addition, G. lichenoides contained more insoluble polysaccharide in cell wall, which might promote the extracellular Cu^2＋-binding as an efficient barrier against metal toxicity. Conversely, G. lemaneiformis was more vulnerable than G. lichenoides to Cu^2＋ toxin for decreases in growth, pigment （chlorophyll a, chlorophyll b, phycobiliprotein, and B-carotene） content, and photosynthetic activity. Moreover, more serious oxidative damages in G. lemaneiformis than in G. lichenoides, in accumulation of reactive oxidative species and malondialdehyde, and in electrolyte leakage, because of lower antioxidant enzyme （superoxide dismutase and glutathione reductase） activities. Therefore, G. lichenoides was less susceptible to Cu〉 stress than G. lemaneiformis.展开更多
文摘[Objective] The aim was to study the effect of the content of copper and zinc on in medium the vitamin E accumulation in wheat embryo-dreived callus.[Method] The mathematical models were established to describe the growth kinetics and the vitamin E accumulation in wheat embryo callus cells.With the aim of getting the highest accumulation of the secondary metabolite Vitamin E,the optimal combination of copper and zinc in medium was confirmed by testing.[Result] The results showed that the production of vitamin E in B5 medium reached the highest value with 2.0 mg/mL ZnSO4·7H2O and 0.1 mg/mL CuSO4·5H2O.The fitting degrees of kinetic models of vitamin E accumulation and cell growth were 97.53% and 95.60%,respectively,which indicated good nonlinear relationships.[Conclusion] Both copper and zinc could affect the accumulation of vitamin E in wheat germ callus,and Copper showed more prominent effect than Zn.Synergism existed in low copper and zinc concentration,and the inhibitive effect enhanced with the increase of the concentrations.
文摘Commelina communis L. growing over some new copper mining wastelands at Bijiashan, Tongling City of Anhui Province, China, was found to be a copper hyperaccumulator. Its copper concentrations were 2707-6159 (4439±2434) mg kg-1, 369-831 (731±142) mg kg-1, and 429-587 (547±57) mg kg-1, respectively, in the roots, stems, and leaves. The soils supporting the growth of the species had a copper concentration ranging from 4620 to 5020 mg kg-1 and averaging 4835±262 mg kg-1, suggesting that the species could not only grow on heavily copper-contaminated soils but also accumulate extraordinarily high concentration of copper. Thus, it shows great potential in the phytoremediation of copper-contaminated soils,the restoration of mined land, geochemical prospecting, and the study of environmental pollution changes.
基金Natural Science Foundation of Zhejiang(LY12C03006),China
文摘This study compared the accumulation of Zn2+and Cu2+in the ovaries and ova of loaches under different concentrations of Zn2+(1.00, 2.50 and 5.00 mg/L respectively) and Cu2+(0.10, 0.25 and 0.50 mg/L respectively). The results showed that both Zn2+and Cu2+accumulated in the ovaries, and that the relationship between accumulation and time was linear over 20 days of exposure. The accumulation of the metals in ovaries was closely related to the concentration of exposure in the solutions(P<0.05), and was obviously affected by the time and doses. However, the Cu2+concentration was significantly higher than Zn2+(P<0.05). The development level of ova in the ovaries also correlated with the concentration and exposure period in the Zn2+and Cu2+solutions.
基金Project(51674303) supported by the National Natural Science Foundation of ChinaProject supported by National Youth Thousand Plan of China+2 种基金Project(2018RS3015) supported by Huxiang High-Level Talent Gathering Program of Hunan Province,ChinaProject(2019CX006) supported by Innovation Driven Program of Central South University,ChinaProject supported by the Research Fund of the Key Laboratory of High Performance Complex Manufacturing at Central South University,China
文摘Cu/Al multilayers were produced by high-temperature accumulative roll bonding(ARB)methods up to three passes.To achieve a high bonding strength,prior to ARB processing,the Cu and Al sheets were heated to 350,400,450 and 500 ℃,respectively.The mechanical properties were evaluated by tensile tests.The microstructure was examined by optical microscopy and scanning electron microscopy equipped with energy dispersive spectrometry.The ultimate tensile stress,the grain size and the thickness of diffusion layer of lamellar composites increase with rolling temperature.When the rolling temperature is 400 ℃,the laminates show the highest ductility,but the yield stress is the lowest.As the rolling temperature further increases,both the yield stress and the ultimate tensile stress increase and the ductility decreases slightly.The mechanical properties of lamellar composites processed by low and high temperature ARB are determined by grain size and the thickness of diffusion layer,respectively.
基金Supported by the Society Development Program of the Natural Science Foundation of Jiangsu Province in China (No.BS2002016)
文摘Heavy metal pollution has become a worldwide problem in aquaculture. We studied copper （Cu^2＋） accumulation and physiological responses of two red algae Gracilaria lemaneiformis and Gracilaria lichenoides from China under Cu^2＋ exposure of 0-500 μg/L in concentration. Compared with G. lemaneiformis, G. lichenoides was more capable in accumulating Cu^2＋, specifically, more Cu〉 on extracellular side （cell wall） than on intracellular side （cytoplasm） and in cell organelles （especially chloroplast, cell nucleus, mitochondria, and ribosome）. In addition, G. lichenoides contained more insoluble polysaccharide in cell wall, which might promote the extracellular Cu^2＋-binding as an efficient barrier against metal toxicity. Conversely, G. lemaneiformis was more vulnerable than G. lichenoides to Cu^2＋ toxin for decreases in growth, pigment （chlorophyll a, chlorophyll b, phycobiliprotein, and B-carotene） content, and photosynthetic activity. Moreover, more serious oxidative damages in G. lemaneiformis than in G. lichenoides, in accumulation of reactive oxidative species and malondialdehyde, and in electrolyte leakage, because of lower antioxidant enzyme （superoxide dismutase and glutathione reductase） activities. Therefore, G. lichenoides was less susceptible to Cu〉 stress than G. lemaneiformis.
