重金属镉胁迫下氮磷对江蓠体内主要抗氧化酶活性的影响

以大型海藻细基江篱繁枝变种(Gracilaria tunuistipitata Var Liui)为实验材料,研究重金属Cd2+胁迫下,无机氮磷作用对藻体各类抗氧化酶类活性的影响,为进一步探索重金属和营养盐复合污染下江蓠对水体的修复能力奠定一定的理论基础.实验结果显示:适当浓度N、P(560 μmol/L、56 μmol/L)的添加能提高藻体内各主要抗氧化酶的活性,降低Cd2+对藻体的毒害作用.不加入N、P或加入过量的N、P(2 160 μmol/L、216 μmol/L)均会抑制藻体内各主要抗氧化酶的活性.从总体上看,同时加入N、P要比加入单一的营养盐更有利于提高藻体内各主要抗氧化酶的活性,增强藻体的抗氧化能力.     

生物炭修复与改良矿区重金属污染土壤的研究进展

概述了生物炭制备的关键影响因素及对矿区重金属污染土壤修复与改良作用的研究进展,在此基础上分析了生物炭修复与改良矿区重金属污染土壤的机理,提出了开展生物炭在实际矿区污染场地的长期性与稳定性行为研究,以及探讨生物炭与不同土壤改良剂的优化组合等建议.     

土壤及场地持久性有机污染的生物修复技术发展及应用

以土壤及场地持久性有机污染物为对象,较为系统地综合评述了国内外污染土壤及场地的生物修复技术发展与应用,并结合当前土壤及场地污染的新特点,提出了生物修复的发展趋势和研究方向.     

长江水系(镇江段)水体和水生生物中重金属的污染现状调查及评价

采用等离子体发射光谱法和原子荧光光谱法对长江水系(镇江段)水体和水生生物中的5种重金属元素含量进行监测,对结果采用单项污染指数评价法和内梅罗综合指数进行分析评价。结果表明,长江水系(镇江段)8个水体采样点中水体的Cd、Cr、Pb、As含量的平均值为0.074、0.015、1.469、2.409μg/L,单项污染指数评价和内梅罗综合指数评价均为未超标及清洁等级;长江水系(镇江段)2个水生生物采样点中2种水生生物中的Cd、Cr、Pb、Hg、As含量的平均值分别为0.004、0.400、0.308、0.001、0.026 mg/kg和0.020、0.200、0.500、0.002、0.041 mg/kg,单项污染指数评价均未超标,内梅罗综合指数评价显示,长江水系(镇江段)中水生生物受Pb不同程度的污染,部分污染指标超标但并不严重。     

Effect of Heavy Metals on the Blood Protein Biochemistry of the Fish CYPRINUS CARPIO AND ITS USE AS A BIO-INDICATOR OF POLLUTION STRESS

Cyprinus carpio were exposed to two non-essential (Hg and Pb)and two essential (Cu and Ni) heavy metal salts at lethal andsub-lethal concentrations. Blood serum total protein, serum globulinand serum albumin was analysed every 2 hr for 24 hrs andagain at 48 and 72 hrs. Serum protein and globulin level showedan intial sharp increase from 2 to 20 hrs, followed by decline thatextend over a period of 72 hrs. Serum albumin showed an initialimmediate decline from 2 to 4 hrs, followed by an intermittent period of recovery and decline that extend over a period of 72hrs. Both lethal and sub-lethal concentrations of metal salts elicited asimilar pattern of response varying only in magnitude. The use offish blood serum protein, albumin and globulin measurements as general indicators of pollutant stress response isdiscussed.     

微波消解-原子吸收光度法测定土壤中铜锌铅镉镍铬

用微波消解－原子吸收光度法测定土壤中铜,锌,铅,镉,镍和铬。通过硝酸－氢氟酸－过氧化氢体系消解液对土壤样品消解,选择出微波最佳消解条件。对硝酸－盐酸－过氧化氢体系消解液和硝酸－氢氟酸－过氧化氢体系消解液进行消解对比试验,发现前者不能将土壤样品完全消解,后者能将样品消解完全,但需将消解液中剩余的酸赶尽,否则测定结果将明显偏低。微波消解土壤与传统电热消解相比,操作简便快速,可提高工作效率。     

用几种溶样方法对典型土样中Pb、Cr、Ni、Cd、Mn、Cu、Zn的溶出情况比较

本文采用HNO_3、HCl-HNO_3、HNO_3-H_2SO_4-HClO_4,溶洋方法消解土样,用原子吸收法测定题述中的元素,并与HCl-HNO_3-HF-HClO_4全消解方法进行了比较.发现除用HF以外的其它酸溶法Pb、Cr的溶出较少溶出比分别低于55％和67％,主要原因是Pb、Cr包藏在土壤的矿物晶格中。     

Bioremediation With Oxygen-Releasing Solids: A Mathematical Model

The use of oxygen releasing solids in passive wells has become of considerable interest in the bioremediation of groundwater contaminated with hydrocarbons and other biodegradable contaminants. Labor, operating, and maintenance costs of this technology are quite competitive with more conventional techniques in many instances. Because of the small rates of mass transport by transverse dispersion, however, a pin-stripe pattern of alternating contaminant and oxygen distribution is expected downgradient of a line of wells which is unacceptable if it extends beyond the point of compliance downgradient. A mathematical model is presented which permits determination of the maximum well spacing in an array of wells which will yield effective remediation within a specified distance of a plume of contaminated groundwater passing through the array. Transverse dispersion of both oxygen and the contaminant is assumed, and biodegradation is modeled by means of Monod kinetics. Longitudinal numerical dispersion is minimized by the use of a asymmetrical upwind algorithm for modeling advection. Modeling results are presented showing the dependence of model behavior on input parameters.     

使用撬装式生物反应器处理含油污泥的现场试验

以长庆油田华池作业区93#井场的修井油泥为对象,添加石油降解菌剂、营养盐、膨松剂,使用撬装式生物反应器控制反应温度及提供全面的机械搅拌增进溶氧量与营养物质的传递速率,对初始含油量为7.24%的含油污泥进行24d的生物强化降解后,含油量下降为0.23%。结果表明,使用撬装式生物反应器可以使微生物快速高效的降解石油污染物,...     

Indigenous Heavy Metal Multiresistant Microbiota of Las Catonas Stream

Las Catonas stream (Buenos Aires Metropolitan Area) receives a complex mixture of pollutants from point and diffuse sources because of the agricultural, industrial and urban land uses of its basin. Widespread detection of heavy metals exceeding aquatic life protection levels has occurred in monitoring reconnaissance studies in surface and pore water. As a result of the screening of Cu, Cd, Zn and Pb resistant/tolerant and culturable microbiota, B101N and 200H strains (Pseudomonas fluorescens or putida) were isolated and selected for further studies. They showed 65% Cd and 35% Zn extraction efficiency from aqueous phase. The potential use of these strains in wastewater treatment is currently investigated in order to contribute to decrease heavy metal pollution, a problem affecting every stream of Buenos Aires Metropolitan Area.     

Application of a Dialysis Sampler to Monitor Phytoremediation Processes

A cylindrical dialysis sampler (1.2 m in length; 5 cm in diameter) was designed and constructed to sample small–scale phytoremediation processes in the root zone of poplar trees. The study site was a 183–tree plantation of hybrid poplars located at Aberdeen Proving Ground, Maryland, at the J–Field Area of Concern. The grove was planted in 1996 to intercept a chlorinated solvent plume containing 1,1,2,2–tetrachloroethane (1,1,2,2–TeCA, trichloroethene (TCE) and daughter products. Two dialysis samplers were installed: one directly in the poplar grove (approximately 0.3 m from the trunk of a mature tree) and the other outside of the grove but in the plume. Data collected included concentrations of chlorinated VOCs, organic acids, chloroacetic acids, Cl⁻, and dissolved gases (ethane, ethene, CH₄, CO₂). At the control location, the VOC profile was dominated by cis– 1,2–dichloroethene (cis–1,2–DCE) and trans–1,2–dichloroethene (trans–1,2–DCE) with concentrations ranging from 0.88-4.5 to 4.4-17.6 mg/L, respectively. Concentrations of VOCs were similar across the vertical profile. At the tree location, 1,1,2,2–TeCA and TCE were the dominant VOCs detected but as opposed to the control location were highly variable within the root zone, with the greatest variability associated with locations in the sampler where roots were observed. This highly variable profile at the tree location is indicative of VOC rhizosphere biodegradation and uptake near the active roots. This variability appears to be on the centimeter scale, emphasizing the importance of these high–resolution samplers for the study of rhizosphere influences.     

双波长标准加入法测微量镍

通过加入掩蔽剂酒石酸,使Zn(Ⅱ）与1－（2－吡啶偶氮）－2－奈酚形成的配合物吸光度降低,而对应的配合物吸光度基本不变,从而提高了大量Zn(Ⅱ)存在下Ni(Ⅱ）测定的准确度,用于测定镀锌溶液中的Ni(Ⅱ）,结果令人满意。     

原子吸收光度法测定树叶中的重金属

用浓硝酸与高氯酸消解树叶,Ｃｕ、Ｚｎ、Ｍｎ含量较高,可直接用火焰原子吸收法测定,含量较低的Ｐｄ、Ｃｄ,Ｃｒ则用石墨炉法测定。Ｐｂ及Ｃｄ含量甚微,受基体及共存元素干扰严重用标准加入法可消除干扰,结果令人满意。     

悬浮液直接进样石墨炉原子吸收法测定湖泊底泥中的铅

试验了悬浮液直接进样平台石墨炉原子吸收分光光度法测定湖泊底泥中的铅。方法特征灵敏度为2 1× 10 -11g/ 0 0 0 44 (A·s) ,检测限 (3σ)为 2 5× 10 -11g ,相对标准差 (n =6 )小于 4% ,加标回收率在 90 %～ 110 %之间