胶质芽孢杆菌、黑曲霉及与沸石联合对模拟废水中Fe3+处理研究

研究沸石、胶质芽孢杆菌(Bacillus mucilaginosus)、黑曲霉(Aspergillus Niger)、胶质芽孢杆菌与沸石联合以及黑曲霉与沸石联合对模拟废水中Fe3+的吸附等温曲线,分析它们对Fe3+模拟废水的吸附及絮凝作用。结果表明：沸石对Fe3+吸附作用符合Freundlich方程;胶质芽孢杆菌分泌含...     

利用甘蔗渣制备微生物絮凝剂的预处理方法研究

通过对甘蔗渣进行不同的预处理,确定了提高纤维素酶糖化率和酱油曲霉发酵液絮凝率的方法.利用正交实验对固液比、颗粒粒径、溶剂浓度和预处理时间及其交互作用进行考察,确定较优的工艺方案.结果表明,在相同条件下,碱处理能够有效提高纤维素酶的糖化率,处理后甘蔗渣的酶解液中还原性糖浓度和酱油曲霉发酵液的絮凝率分别为3.46 g/L和...     

对氯苯酚废水的电化学降解研究

实验利用电沉积法制备的不锈钢基PbO2电极,以对氯苯酚溶液为模型废水,通过静态实验研究外加电压、电解质浓度、曝气量及初始pH值对电化学氧化降解对氯苯酚效果的影响。结果表明,实验制备的PbO2电极具有较高的电催化活性,能够有效降解对氯苯酚;较低的操作电压有助于降低处理成本;随着电解质浓度和曝气量的增加,对氯苯酚去除率均呈...     

HFBM工艺处理三羟甲基丙烷废水的中试研究

采用厌氧滤池+HFBM工艺处理三羟甲基丙烷废水,在进水CODCr浓度小于10 000 mg.L-1、水力停留时间为96 h条件下,出水CODCr浓度稳定在500 mg.L-1以下,在进水中含0.5%甲醛条件下,经过7 d的冲击试验,出水CODCr浓度仍能保证在500 mg.L-1以下,中试试验直接运行费用为6.96元/t废水。     

Bioconversion of dairy manure by black soldier fly (Diptera: Stratiomyidae) for biodiesel and sugar production

Modern dairies cause the accumulation of considerable quantity of dairy manure which is a potential hazard to the environment. Dairy manure can also act as a principal larval resource for many insects such as the black soldier fly, Hermetia illucens. The black soldier fly larvae (BSFL) are considered as a new biotechnology to convert dairy manure into biodiesel and sugar. BSFL are a common colonizer of large variety of decomposing organic material in temperate and tropical areas. Adults do not need to be fed, except to take water, and acquired enough nutrition during larval development for reproduction. Dairy manure treated by BSFL is an economical way in animal facilities. Grease could be extracted from BSFL by petroleum ether, and then be treated with a two-step method to produce biodiesel. The digested dairy manure was hydrolyzed into sugar. In this study, approximately 1248.6 g fresh dairy manure was converted into 273.4 g dry residue by 1200 BSFL in 21 days. Approximately 15.8 g of biodiesel was gained from 70.8 g dry BSFL, and 96.2 g sugar was obtained from the digested dairy manure. The residual dry BSFL after grease extraction can be used as protein feedstuff.     

某采油区石油污染土壤微生物群落特征研究

采用Biolog方法、最大或然数和主成分分析方法研究了某采油区污染场地及周围土壤的污染特征、微生物数量、微生物群落功能多样性以及相互作用关系.结果表明,土壤均一定程度受到石油污染,污染场地土壤呈现以萜类、姥鲛烷及植烷等难降解物质为主的污染特征,其土壤中微生物数量最多,总活菌数为1.73×1010个/g,石油烃降解菌数为...     

嗜麦芽窄食单胞菌对镉的吸附

利用从重金属镉污染地分离并纯化得到的1株嗜麦芽窄食单胞菌(Stenotrophomonas maltophilia)作为吸附剂,考察了镉初始浓度、菌浓度、吸附时间、温度及pH对镉吸附效果的影响.结果表明,在镉初始质量浓度为1.0 mg/L、30℃、pH为6～7条件下,菌质量浓度为2.0 g/L时,吸附120 min对镉...     

Sequestration of organochlorine pesticides in soils of distinct organic carbon content

In the present study, five soil samples with organic carbon contents ranging from 0.23% to 7.1% and aged with technical dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) for 15 months were incubated in a sealed chamber to investigate the dynamic changes of the OCP residues. The residues in the soils decreased over the incubation period and finally reached a plateau. Regression analysis showed that degradable fractions of OCPs were negatively correlated with soil organic carbon (SOC) except for α-HCH, while no correlation was found between degradation rate and SOC, which demonstrated that SOC content determines the OCP sequestration fraction in soil. Analysis of the ratio of DDT and its primary metabolites showed that, since it depends on differential sequestration among them, magnitude of (p,p′-DDE + p,p′-DDD)/p,p′-DDT is not a reliable criterion for the identification of new DDT sources.     

Bioanalytical and instrumental analysis of thyroid hormone disrupting compounds in water sources along the Yangtze River

Thyroid hormone (TH) agonist and antagonist activities of water sources along the Yangtze River in China were surveyed by a green monkey kidney fibroblast (CV-1) cell-based TH reporter gene assay. Instrumental analysis was conducted to identify the responsible thyroid-active compounds. Instrumentally derived l-3,5,3′-triiodothyronine (T₃) equivalents (T₃-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to dibutyl phthalate (DBP-EQs) were calculated from the concentrations of individual congeners. The reporter gene assay demonstrated that three out of eleven water sources contained TR agonist activity equivalents (TR-EQs), ranging from 286 to 293 ng T₃/L. Anti-thyroid hormone activities were found in all water sources with the TR antagonist activity equivalents referring to DBP (Ant-TR-EQs), ranging from 51.5 to 555.3 μg/L. Comparisons of the equivalents from instrumental and biological assays suggested that high concentrations of DBP and di-2-ethylhexyl phthalate (DEHP) were responsible for the observed TR antagonist activities at some locations along the Yangtze River.     

氢氧化镁混凝过程絮体形成研究

以不同浊度高岭土水样为研究对象,运用激光光散射法对氢氧化镁混凝剂絮体开始形成时间和氯化镁最小投加量进行测定,探讨了氯化镁投加量对沉后出水浊度和Zeta电位的影响.结果表明:(1)氢氧化镁混凝剂絮体开始形成时间随着氯化镁投加量的增大而缩短;pH增大及浊度增大时,絮体开始形成时间总体缩短,pH=11.5、氯化镁投加量为25...