以三叶浮萍为对象,研究了异恶草酮对其生长及体内色素的影响作用。结果表明:异恶草酮对浮萍生长抑制的24 hIC50为8.86 mg/L4、8 h IC50为5.21 mg/L7、2 h IC50为1.92 mg/L、96 h IC50为1.66 mg/L,对浮萍体内叶色素的影响作用呈良好的浓...以三叶浮萍为对象,研究了异恶草酮对其生长及体内色素的影响作用。结果表明:异恶草酮对浮萍生长抑制的24 hIC50为8.86 mg/L4、8 h IC50为5.21 mg/L7、2 h IC50为1.92 mg/L、96 h IC50为1.66 mg/L,对浮萍体内叶色素的影响作用呈良好的浓度(剂量)-效应关系,随着处理浓度的增大,浮萍体内的叶绿素和胡萝卜素含量明显减少,且叶绿素a/b值也随处理浓度的增大而减小。展开更多
The effect of sulfur addition/solids content(SA/SC)ratio on heavy metals(e.g.copper,zinc and lead)obtained from mine tailings by indigenous sulfur-oxidizing bacteria was studied,and the changes in the chemical forms o...The effect of sulfur addition/solids content(SA/SC)ratio on heavy metals(e.g.copper,zinc and lead)obtained from mine tailings by indigenous sulfur-oxidizing bacteria was studied,and the changes in the chemical forms of heavy metals after bioleaching were explored.The results show that the solubilization of metals is significantly influenced by SA/SC ratio,and SA/SC ratio of 2.50 is found to be the best for bacterial activity and metal solubilization among six SA/SC ratios tested(such as 1.00,1.33,1.50,1.67,2.00 and 2.50)under the chosen experimental conditions.The pH decreases fast and the maximum solubilizations of copper and zinc are respectively 81.76% and 84.35% while that of lead only reaches 40.36%.After bioleaching,the chemical forms of heavy metals have changed.The metals remained in mine tailings are mainly found in residual fractions,which is harmless to the surrounding environment.展开更多
Fenton oxidation was used as the pretreatment of 2-chlorophenol wastewater with the objective of dechlorination, as it was considered that after breakage of aryl—Cl bond, the generated intermediates may be easily bio...Fenton oxidation was used as the pretreatment of 2-chlorophenol wastewater with the objective of dechlorination, as it was considered that after breakage of aryl—Cl bond, the generated intermediates may be easily biodegraded. Hence, the optimization of pH and the low Fenton reagent doses for dechlorination was investigated. More than 99% dechlorination is obtained at the optimal pH 4 and the Fenton reagent doses of 86 mmol/L H2 O2 and 2.87 mmol/L Fe2+. The corresponding 2-chlorophenol is degraded completely, 80.02% COD is also removed, and the biodegradability, evaluated in terms of the BOD5 /COD ratio, is increased up to 0.41. To test the effect of this pretreatment, the pretreated 2-chlorophenol wastewater was fed to a sequencing batch reactor(SBR). The results show that complete mineralization is achieved. It is demonstrated that, for the treatment of recalcitrant compounds like 2-chlorophenol, the Fenton pretreatment could be quite effective and economical for enhancing the biodegradability in a Fenton-biological coupled system.展开更多
文摘以三叶浮萍为对象,研究了异恶草酮对其生长及体内色素的影响作用。结果表明:异恶草酮对浮萍生长抑制的24 hIC50为8.86 mg/L4、8 h IC50为5.21 mg/L7、2 h IC50为1.92 mg/L、96 h IC50为1.66 mg/L,对浮萍体内叶色素的影响作用呈良好的浓度(剂量)-效应关系,随着处理浓度的增大,浮萍体内的叶绿素和胡萝卜素含量明显减少,且叶绿素a/b值也随处理浓度的增大而减小。
基金Project(11JJ2031)supported by the Key Project of Natural Science Foundation of Hunan Province,ChinaProject(2009SK3029)supported by the Plan Science and Technology Department of Hunan Province,China
基金Project(11JJ2031)supported by the Key Project of Natural Fund of Hunan Province,ChinaProject(2009SK3029)supported by the Plan of Hunan Provincial Science and Technology Department,China
文摘The effect of sulfur addition/solids content(SA/SC)ratio on heavy metals(e.g.copper,zinc and lead)obtained from mine tailings by indigenous sulfur-oxidizing bacteria was studied,and the changes in the chemical forms of heavy metals after bioleaching were explored.The results show that the solubilization of metals is significantly influenced by SA/SC ratio,and SA/SC ratio of 2.50 is found to be the best for bacterial activity and metal solubilization among six SA/SC ratios tested(such as 1.00,1.33,1.50,1.67,2.00 and 2.50)under the chosen experimental conditions.The pH decreases fast and the maximum solubilizations of copper and zinc are respectively 81.76% and 84.35% while that of lead only reaches 40.36%.After bioleaching,the chemical forms of heavy metals have changed.The metals remained in mine tailings are mainly found in residual fractions,which is harmless to the surrounding environment.
基金Project(11JJ2031) supported by the Natural Science Fund of Hunan Province,China
文摘Fenton oxidation was used as the pretreatment of 2-chlorophenol wastewater with the objective of dechlorination, as it was considered that after breakage of aryl—Cl bond, the generated intermediates may be easily biodegraded. Hence, the optimization of pH and the low Fenton reagent doses for dechlorination was investigated. More than 99% dechlorination is obtained at the optimal pH 4 and the Fenton reagent doses of 86 mmol/L H2 O2 and 2.87 mmol/L Fe2+. The corresponding 2-chlorophenol is degraded completely, 80.02% COD is also removed, and the biodegradability, evaluated in terms of the BOD5 /COD ratio, is increased up to 0.41. To test the effect of this pretreatment, the pretreated 2-chlorophenol wastewater was fed to a sequencing batch reactor(SBR). The results show that complete mineralization is achieved. It is demonstrated that, for the treatment of recalcitrant compounds like 2-chlorophenol, the Fenton pretreatment could be quite effective and economical for enhancing the biodegradability in a Fenton-biological coupled system.
