重金属

The average concentrations of Cr, Cd and Pb in ectoskeleton, liver, and muscle were 4.03, 0.12 and 12.31 μgg^(-1), 3.88, 1.04 and 9.12 μgg^(-1), and 4.16, 0.09 and 0.72 μgg^(-1), respectively. Among the three test sites, there existed significant differences in the enrichment of Cr in ectoskeleton and muscle, and of Cr, Cd and Pb in liver. The enrichment of test heavy metals had no notable correlation with the body mass of P. clarkia, and no significant difference was found in the enrichment of the heavy metals between female and male individuals.

外骨骼中Cr、Cd、Pb的平均含量分别为4.03、0.12和12.31μgg^(-1)，合肥市、肥西、肥东三地之间除Cr的富集量差异极显著外，其他2种重金属的富集量差异都不显著；肝脏中Cr、Cd、Pb的平均含量分别为3.88、1.04和9.12μgg^(-1)，3个地区重金属的富集量的差异都极其显著；肌肉中Cr、Cd、Pb的平均含量分别为4.16、0.09和0.72μgg^(-1)，3个地区除重金属Cr的富集量差异极显著外，Cd和Pb的差异都不显著。3种重金属污染物的富集量与体质量没有明显的相关性。3种重金属在雌雄个体之间的富集差异不显著。

In order to find out completely the soil-wheat contaiminated by heavy metals in Tianjin sewage farm, we collect samples on the dry land and examinate contents of heavy metals in soil-wheat system. Firstly, the anthor evaluates that soil irrigated by sewage that has been contaminated slightly, the main polluting factors are Cd and Zn, and then the anthor evaluates soil according to different regions, soil types and irrigating water. Secondly, the anthor analyzes content and enrichment ability of heavy metals in different part of wheat, evaluates wheat is contaiminated by Cd widespreadly, only few samples polluted by Zn.Finally the anthor put up correlative analysis about heavy metal contents in the soil-wheat system, as well as plant enrichment coefficient and some physico-chemical properties of soil, and establishes a prognostic model about heavy metal content among wheat spike, soil, soil types, PH, organic matter and salinity with the quantifying theory.The prognostic accuracy of primarily contaminative factors is the best with compound correlative coefficient examining, the model can be founded.With improvement of living level, people need cleaner food.

为全面了解天津市污灌区农产品生产地土壤和旱地作物小麦的重金属污染状况，我们于2004～2005年对全市污灌区的土壤和小麦进行了采样，在对该区土壤—小麦系统中六种重金属元素(Cd、Cu、Pb、Zn、Cr和Ni)的含量进行检测的基础上，本文首先分析评价了污灌区农田土壤的环境质量总体已达到了轻度污染水平，主要的污染因子是Cd和Zn，同时对污灌区农田土壤分区县、土壤类型和不同灌水类型进行了评价；然后分析了重金属在小麦不同部位的含量与富集能力，评价了污灌区旱地作物小麦普遍遭受了Cd的污染，只有个别样点遭受了Zn的污染；最后对土壤—小麦系统重金属含量间以及植物富集系数与土壤部分理化性质间进行了相关分析，由于土壤类型是定性变量，本论文以数量化理论建立了小麦穗实中重金属含量与土壤中重金属全量、土壤类型、PH值、有机质和全盐量间的预测模型，经复相关系数检验，污灌区主要的污染因子Cd和Zn的预测精度最高，模型可以成立。

Based on the evaluation system, the plants whose relative remediation age was between 0~10 years were named as"Hyperaccumulator"and those between 10 ~ 50 years were named as"Accumulator".7 In the experiments six kinds of substrates were mixed with different solid wastes and the absorption and enrichment of plants on heavy metal Cd was studied. The results showed that relative remediation age was an ideal index to evaluate the capability of the phytoremediation on heavy metals, because it took into account more factors which affected the absorption evaluation effects than others, such as the heavy metal content and the biomass of the over-ground part of plants, the heavy metal content and the whole gross in substrates, harvesting frequency of plants and the environment standard of heavy metal. This made relative remediation age be suitable to the sorption capability evaluation of not only different plants on one heavy metal but also one plant on different heavy metals.8 It can be drawn from the relative remediation age of heavy metal Cd that the absorption capability of different plants was not same.

以相对修复年限为评价指标定义相对修复年限为0-10年的植物为"超富集植物"，10-50年的植物为"富集植物"。7在由不同废弃物按一定的比例混合配制的六种土地复垦基质上，系统地研究了几种植物对重金属镉的吸收和富集情况，结果表明，相对修复年限既适用于不同植物对同一种重金属元素的吸收能力的评价，又适用于同一植物对不同重金属元素的吸收能力的评价，是衡量重金属元素植物修复效果的理想指标。8从不同植物对同一基质重金属镉的吸收和富集能力看，不论是经过多年种植的基质，还是第一次种植的基质，小白菜和油菜都是相对理想的植物；而黑麦草、高羊茅和苜蓿的吸收效果并不理想。

According to the composting principle and the correlation between the forms of heavy metals and biological efficiency, combining with the controlling means of heavy metals' activity, this test studied the effect of passivation reagents including fly ash, phosphorate rock, zeolite, peat and lime on the forms and the biological efficiency of heavy metals; and the different perception of different passivation reagents were screened and optimized. Basing on the study, the adsorption mechanism of passivation reagents on heavy metals in sewage sludge composting was discussed, and the transformation mechanism of organic forms of heavy metals was also studied through some methods including dialysis and G-75 gel chromatogram separation etc.

本研究根据固体废弃物的堆肥化原理及重金属的不同形态与生物有效性的关系，结合污泥中重金属活性的控制方法，研究了在污泥堆肥中添加粉煤灰、磷矿粉、草炭、沸石和石灰对重金属的形态及重金属的生物有效性的影响，并对不同钝化剂的不同配比进行了筛选和优化；在此研究基础上，探讨了污泥堆肥中钝化剂对重金属的吸附机理，运用透析及G-75凝胶色谱分离等方法研究了污泥堆肥中重金属有机形态的转变机理。

The results are as following: The concentrations of Cr, Cu, Pb, Cd, Zn, As and Hg were 0.57 7.37 l.89 0.18 36.99 l.57 0.018μgL^(-1) in the seawater, respectively. They are 30.11、30.62、32.61、0.106、68.56、2.48、0.027×10^(-6) in the sediment, respectively. Except Zn, other heavy metals are determined in the organisms. The concentrations of heavy metals are more in razor clam than in the mullet.

结果表明，表层海水中重金属Cr、Cu、Pb、Cd、Zn、AS和Hg的平均浓度分别为0.57、7.37、1.89、0.18、36.99、1.57、0.018μgL^(-1)；表层沉积物中重金属Cr、Cu、Pb、Cd、Zn、A，和Hg的浓度分别为30.11、30.62、32.61、0.106、68.56、2.45、0.027×10^(-6)气生物体内除了鲻鱼中未检出Zn外，七种重金属在缢蛏、鲻鱼体内均有检出，且缢蛏中重金属含量明显高于鲻鱼体内重金属的含量。

Results show that, following the leaching time extending, the leaching concentrations of heavy metals and lixiviate toxicity of heavy metals increase in the fly ash. When the ratio of liquid and solid add, the leaching concentrations of heavy metals obviously become big, and the Cd's leaching concentration is the biggest, when the ratio of liquid and solid is 90, the Cd's leaching ratio exceed the percent of 70. At the time pH is about 7, the leaching concentrations of heavy metals are the lowest. When the grain size is the bigger or little, the leaching concentrations of heavy metals are lower, however when the grain size is 250-900 μm, the concentrations are higher. After fly ash melt in the high temperature, the lixiviate toxicity of heavy metals greatly reduce, which explains that the effect of melting on heavy metals' stabilization is very good.

结果表明，随着浸出时间的增加，飞灰绝大部分重金属的浸出浓度增高，浸出毒性增强；液固比增加，大部分重金属的浸出率大大提高，其中重金属Cd的浸出率最大，在液固比为90时，飞灰中的Cd的浸出率达到70%以上；pH为中性左右的时候，医疗垃圾飞灰中的大部分重金属的浸出液浓度最低；颗粒尺寸在较大或者较小时，医疗垃圾飞灰中的大部分重金属浸出浓度较小，大部分重金属在颗粒尺寸250～900 μm时，重金属的浸出浓度较高；飞灰高温熔融后，重金属的浸出毒性大大降低，说明熔融对重金属有很好的固化效果。

Reactive oxygen species causing DNA oxidative damage comes from two kinds of ways:one is from cellular normal physiological metabolism;the other is from outer environment.Redox-sensitive green fluorescent protein was expressed in Saccharomyces cerevisiae.Recombinant cells were evaluated in monitoring the changes in the redox state of living cells when challenged with toxicologically relevant metal ions NaAsO_2 or Pb(NO_3)_2 by measuring emission intensity at 510 nm with a Hitachi F6500 fluorescence spectrophotometer,roGFP expressed in yeast responded not only to typical membrane-permeant oxidants H_2O_2 and reductants DTT,but also to toxicological metal ion-induced intracellular redox changes in a dose-dependent manner.Moreover,exposure of yeast cells to NaAsO_2 or Pb(NO_3)_2 at concentrations that induced redox changes reported by roGFP caused up to 2～3 fold increases in DNA mutation frequency.This mutagenic effect was largely caused by oxidative stress since blocking the production of hydryl radicals with thiourea significantly reduced the mutation rate as well as delayed the cell death.

本文将对氧化还原状态变化敏感的绿色荧光蛋白roGFP1-R12，在酵母细胞中实现了多拷贝强表达；荧光扫描经强氧化剂H_2O_2和还原剂DTT以及环境中重金属NaAsO_2或Pb(NO_3)_2处理后的酵母细胞悬液，测定510 nm处的荧光发射强度结果显示，表达的绿色荧光蛋白对氧化还原水平敏感，且在510 nm处的荧光强度与一定的重金属浓度呈正相关，即roGFP1-R12在510nm处的荧光发射值随重金属浓度的增高而增强，从而说明重金属对细胞的毒性在一定程度上很可能是通过破坏细胞内的氧化还原平衡发生作用；同时通过该绿色荧光蛋白对胞内氧化还原状态变化的响应情况可以来实时检测环境中的重金属；遗传学的点突变频率及致死率实验数据表明，重金属能导致菌体的点突变频率和致死率升高，且活性氧的清除剂巯基脲能明显降低这种点突变和致死率，说明由重金属引发的这种点突变和致死效应在很大程度上是依赖于重金属对细胞诱导产生的氧化胁迫。

Compared of the efficiency of treating heavy metals in FGD wastewater with NaOH, Ca_2 and Mg_2. It indicated that NaOH was much efficient for precipitated waste water; Ca_2 was much efficient for unprecipitated waste water, the removal efficiency reached 98.4%. With the increasing of the main ion of Ca~2+, Cl~- in FGD wastewater, the efficiency decreased. It decreased 60% for the removing of Mn and 10% for Zn, Cd and Ni. The rectification coefficient token the Ksp of practical wastewater because it quite different with theoretic Ksp at different pH; the theoretic and practice addition were proportioned and it commonly reached 1:300.The precipitation efficiency of Na2S at different pH and the effect of Ca2+ was determined.

比较了NaOH、Ca_2和Mg_2处理脱硫废水时重金属的去除效果，分析了Ca~(2+)、SO_4~(2-)和Cl~-等主要离子的影响，结果表明：NaOH和Ca_2能有效处理脱硫废水中的重金属；对澄清废水而言，NaOH效果较好，对于未澄清废水而言，Ca_2效果更好，但去除废水中重金属的效率都能达到98.4%；随着Ca~(2+)、Cl~-等主要离子浓度的增大，中和作用去除重金属的效率降低，Mn最大降低60%，Zn，Cd，Ni降低10%左右；实际重金属浓度和用理论Ksp计算所得值差别很大，通过校正系数能有效计算实际重金属浓度；实现相同pH时氢氧化物的理论和实际投加量成一定比例，最大可达1：500。

Environmental protection and sustainable development in agriculture has become key problems of human being in nowadays,and the heavy metal contaminates is one of severe pollutive originations,which enters the human body by food chain and endangers the health of human being. In this paper,the origination of heavy metal in soil was conducted and the review about the methods of heavy metal spacial variation in soil was discussed. The proposed implications were as follow:① the study on spacial variation of the heavy metal should be conducted by Geostatistical methods combinated with 3S technic;②a model about the geostatistics and the spacial variation of heavy metal was built.

环境保护及农业可持续发展成为当今世界人类面临的重要课题，重金属污染尤为突出，并通过食物链进入人体，对人体健康构成极大危害；本文简要分析了土壤重金属的来源，并对土壤重金属特性空间变异定量研究中所涉及的主要分析方法作了初步介绍；提出了重金属特性空间变异定量研究方法的两点启示：①地统计学与3S技术的结合来研究重金属空间变异；②提出了地统计学与土壤重金属空间变异分布建模。

When hexanoic acid and heavy metal ions coexist in the solution,the adsorption of metal ions by clay tends to decrease because of the competitive adsorption of hexanoic acid.

当溶液中己酸和重金属共存时，由于竞争吸附使得粘土对重金属的吸附能力普遍有较小幅度的下降；当溶液中存在腐殖酸和重金属共存时，粘土对重金属的吸附能力增强，主要是由于酸性条件下富里酸发生解离后与重金属络合，其络合物与粘土颗粒有一定的结合能力，增强了粘土对重金属的吸附能力。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。