Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most ...Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most heavy metals are transported into the marine environment and accumulated without decomposition. The aim of the present study is to investigate the effects on growth, pigments, lipid peroxidation, and some antioxidant enzyme activities of marine microalga Pavlova viridis, in response to elevated concentrations of cobalt （Co） and manganese （Mn）, especially with regard to the involvement of antioxidative defences against heavy metal-induced oxidative stress. In response to Co^2＋, lipid peroxidation was enhanced compared to the control, as an indication of the oxidative damage caused by metal concentration assayed in the microalgal cells but not Mn^2＋. Exposure of Pavlova viridis to the two metals caused changes in enzyme activities in a different manner, depending on the metal assayed： after Co^2＋ treatments, total superoxide dismutase （SOD） activity was irregular, although it was not significantly affected by Mn^2＋ exposure. Co^2＋ and Mn^2＋ stimulated the activities of catalase （CAT） and glutathione （GSH）, whereas, glutathione peroxidase （GPX） showed a remarkable increase in activity in response to Co^2＋ treatments and decreased gradually with Mn^2＋ concentration, up to 50 μmol/L, and then rose very rapidly, reaching to about 38.98% at 200 μmol/L Mn^2＋. These results suggest that an activation of some antioxidant enzymes was enhanced, to counteract the oxidative stress induced by the two metals at higher concentration.展开更多
The work concerned the electrochemical behaviors of Y(Ⅲ)on W and Ni electrodes in molten LiCl-KCl salts by a series of electrochemical techniques.The electrochemical reaction of Y(Ⅲ)to Y(0)proceeded in a one-step re...The work concerned the electrochemical behaviors of Y(Ⅲ)on W and Ni electrodes in molten LiCl-KCl salts by a series of electrochemical techniques.The electrochemical reaction of Y(Ⅲ)to Y(0)proceeded in a one-step reduction process with the exchange of three electrons,Y(Ⅲ)+3e^–→Y(0).Compared with the cyclic voltammogram and square wave voltammogram obtained on W electrode,the reduction potential of Y(Ⅲ)on Ni electrode was observed at less negative potential than the one of Y(Ⅲ)to give pure Y metal on W electrode,which revealed the occurrence of underpotential deposition of Y(Ⅲ)on Ni electrode.Electromotive force(emf)measurements were performed to calculate the relative partial molar Gibbs energies and activities of Y in Y-Ni alloys.The standard Gibbs energies of formation for different Y-Ni intermetallic compounds were also estimated.The different Y-Ni alloys were formed by potentiostatic electrolysis at different potentials and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).It was found that four intermetallic compounds,YNi5,Y2Ni7,YNi3 and YNi2,were selectively produced by controlling applied potential.展开更多
Objective To assess lipid peroxidation and ultrastructural modifications in rat brains following perinatal exposure to lead （Pb） and/or cadmium （Cd）. Methods Female rats were divided into four groups： control gro...Objective To assess lipid peroxidation and ultrastructural modifications in rat brains following perinatal exposure to lead （Pb） and/or cadmium （Cd）. Methods Female rats were divided into four groups： control group, Pb （300 mg/L） group, Cd group （10 mg/L） and Pb＋Cd （300 mg/L, 10 mg/L） group. The compounds were delivered in the drinking water throughout pregnancy and lactation. Results The levels of compounds in blood and brain of the Pb＋Cd group were similar to those of other groups, but the effects of Pb＋Cd on pups＇ body and brain weights were higher than on other compounds. Electron microscopy revealed that Pb and Cd had effects on mitochondrial swelling, disruption and cristae loss, Nissl body dissolution, degenerated organelles and vacuoles, cytomembrane disappearance, and nuclear chromoplasm concentration. The activity of glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, catalase （CAT）, acetylcholinesterase （ACHE） was decreased, whereas the activity of maleic dialdehyde （MDA） was increased. Conclusion Perinatal exposure to low doses of Pb and Cd can produce alterations in lipid peroxidation and ultrastructural modifications in rat brains, and exposure to both metals can result in greater damages.展开更多
To determine the fertilization effect of the rapeseed green manure Youfei1, we assessed soil physical and chemical properties and the yield of succeeding crop before and after planting Youfei 1. Compared with basal so...To determine the fertilization effect of the rapeseed green manure Youfei1, we assessed soil physical and chemical properties and the yield of succeeding crop before and after planting Youfei 1. Compared with basal soil samples and controls,improvements were observed in the soil content of available N, P, K, and organic matter. The content of available K and organic matter increased significantly by17.99% and 25.45%. The soil pH did not change noticeably, but the soil bulk density decreased significantly by 22.55%. After planting Youfei 1, the yield of a succeeding rice crop increased significantly by 6.62% in two years. We conclude that planting Youfei 1 can help maintain and improve soil fertility and significantly increase the yield of succeeding crop.展开更多
基金Project supported by the Natural Science Foundation of Jiangsu Province(No.95021301)China Postdoctoral Science Foundation(No.2005037121)Jiangsu Planned Projects for Postdoctoral Research Funds(No.0401001C)
文摘Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most heavy metals are transported into the marine environment and accumulated without decomposition. The aim of the present study is to investigate the effects on growth, pigments, lipid peroxidation, and some antioxidant enzyme activities of marine microalga Pavlova viridis, in response to elevated concentrations of cobalt （Co） and manganese （Mn）, especially with regard to the involvement of antioxidative defences against heavy metal-induced oxidative stress. In response to Co^2＋, lipid peroxidation was enhanced compared to the control, as an indication of the oxidative damage caused by metal concentration assayed in the microalgal cells but not Mn^2＋. Exposure of Pavlova viridis to the two metals caused changes in enzyme activities in a different manner, depending on the metal assayed： after Co^2＋ treatments, total superoxide dismutase （SOD） activity was irregular, although it was not significantly affected by Mn^2＋ exposure. Co^2＋ and Mn^2＋ stimulated the activities of catalase （CAT） and glutathione （GSH）, whereas, glutathione peroxidase （GPX） showed a remarkable increase in activity in response to Co^2＋ treatments and decreased gradually with Mn^2＋ concentration, up to 50 μmol/L, and then rose very rapidly, reaching to about 38.98% at 200 μmol/L Mn^2＋. These results suggest that an activation of some antioxidant enzymes was enhanced, to counteract the oxidative stress induced by the two metals at higher concentration.
基金Project supported by the National Natural Science Foundation of China(21271054,11575047,21173060,11675044)the Major Research Plan of the National Natural Science Foundation of China(91326113,91226201)the Fundamental Research Funds for the Central Universities(HEUCF2016012)
文摘The work concerned the electrochemical behaviors of Y(Ⅲ)on W and Ni electrodes in molten LiCl-KCl salts by a series of electrochemical techniques.The electrochemical reaction of Y(Ⅲ)to Y(0)proceeded in a one-step reduction process with the exchange of three electrons,Y(Ⅲ)+3e^–→Y(0).Compared with the cyclic voltammogram and square wave voltammogram obtained on W electrode,the reduction potential of Y(Ⅲ)on Ni electrode was observed at less negative potential than the one of Y(Ⅲ)to give pure Y metal on W electrode,which revealed the occurrence of underpotential deposition of Y(Ⅲ)on Ni electrode.Electromotive force(emf)measurements were performed to calculate the relative partial molar Gibbs energies and activities of Y in Y-Ni alloys.The standard Gibbs energies of formation for different Y-Ni intermetallic compounds were also estimated.The different Y-Ni alloys were formed by potentiostatic electrolysis at different potentials and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).It was found that four intermetallic compounds,YNi5,Y2Ni7,YNi3 and YNi2,were selectively produced by controlling applied potential.
基金supported by a grant from the National Natural Science Foundation of China (No. 30440050 and No. 305713647)
文摘Objective To assess lipid peroxidation and ultrastructural modifications in rat brains following perinatal exposure to lead （Pb） and/or cadmium （Cd）. Methods Female rats were divided into four groups： control group, Pb （300 mg/L） group, Cd group （10 mg/L） and Pb＋Cd （300 mg/L, 10 mg/L） group. The compounds were delivered in the drinking water throughout pregnancy and lactation. Results The levels of compounds in blood and brain of the Pb＋Cd group were similar to those of other groups, but the effects of Pb＋Cd on pups＇ body and brain weights were higher than on other compounds. Electron microscopy revealed that Pb and Cd had effects on mitochondrial swelling, disruption and cristae loss, Nissl body dissolution, degenerated organelles and vacuoles, cytomembrane disappearance, and nuclear chromoplasm concentration. The activity of glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, catalase （CAT）, acetylcholinesterase （ACHE） was decreased, whereas the activity of maleic dialdehyde （MDA） was increased. Conclusion Perinatal exposure to low doses of Pb and Cd can produce alterations in lipid peroxidation and ultrastructural modifications in rat brains, and exposure to both metals can result in greater damages.
基金Supported by Hunan Youth Talents Training Joint Fund Project(2016JJ6073)Science and Technology Innovation Project of Hunan Academy of Agricultural Sciences(2017JC33)Construction of Modern Agricultural Industry Technology System(CARS-12)~~
文摘To determine the fertilization effect of the rapeseed green manure Youfei1, we assessed soil physical and chemical properties and the yield of succeeding crop before and after planting Youfei 1. Compared with basal soil samples and controls,improvements were observed in the soil content of available N, P, K, and organic matter. The content of available K and organic matter increased significantly by17.99% and 25.45%. The soil pH did not change noticeably, but the soil bulk density decreased significantly by 22.55%. After planting Youfei 1, the yield of a succeeding rice crop increased significantly by 6.62% in two years. We conclude that planting Youfei 1 can help maintain and improve soil fertility and significantly increase the yield of succeeding crop.
