模拟酸雨条件下降尘中Cu,Pb,Zn,Cr各形态的溶出和转化研究

本文用Ｔｅｓｓｌｅｒ方法，研究了模拟酸雨条件下，降尘中Ｃｕ，Ｐｂ，Ｚｎ，Ｃｒ各形态的溶出和相互转化。试验表明：（１）降尘中Ｃｕ，Ｃｒ的溶出量随酸雨酸度的增大而增加；Ｐｂ，Ｚｎ没分别在ＰＨ＝３．５和ＰＨ＝４．５时溶出量最大，溶出的金属多源于可交换态和碳酸盐结合态，说明这两种形态的稳定性较差。（２）在模拟酸雨条件下，Ｃｕ，Ｐｂ，Ｚｎ，Ｃｒ各形态的含量发生了较大变化；Ｃｕ从其优势形态有机结合态向可交换态     

Nutrients Can Enhance Phytoremediation of Copper-Polluted Soil by Indian Mustard

An orthogonally designed experiment was conducted to study the single and combined effects of N, P and K on phytoremediation of Cu-polluted soil by Indian mustard. Addition of fertilizer N and P significantly increased Indian mustard shoot yield. Two high treatments combined with N resulted in the highest yields, followed by low-P combined with N. In contrast, high P with no N gave no yield increase and K had no effect on yield of Indian mustard. Nitrogen and P increased the amount of chlorophyll in the leaves, indicating that the yield increases were due to enhanced photosynthesis. Nitrogen application had no effect on plant Cu concentrations but addition of P slightly decreased plant Cu concentrations, likely a dilution effect resulting from the increase in yield. Among the treatments, N and P applied at 100 and 200 mg kg^–1 respectively with no K application resulted in the highest Cu uptake. Thus, a combination of low N and high P produced a yield increase in Indian mustard that was more than adequate to compensate for a slight decrease in Cu concentration, resulting in the highest Cu removal from the contaminated soil.     

沉积物中腐殖质对铜毒性的影响

东湖沉积物中掺入腐殖质与铜 ,得到总有机碳 (TOC) 1.4 5 %～ 5 .72 %、总铜 (TCu) 12 0～ 2 70 0mg/kg的污染沉积物样品 ,离心法制取沉积物间隙水 .间隙水对大型溞 (Daphniamagna)进行 4 8h急性毒性试验 .沉积物及间隙水的化学分析表明 :间隙水中可溶性有机碳 (DOC)、铜 (Cu)、铁 (Fe)、锰 (Mn)、钙 (Ca)与沉积物中TOC和TCu含量关系呈现不同的变化规律 .多元分析表明 :间隙水中铜对大型溞的急性毒性 ,随沉积物中TOC含量的升高而减弱 ,随沉积物中总铜含量的增加而增强 ,多元回归方程为 :LC50 =- 0 .13179+0 .0 780 7[TOC]- 0 .0 0 0 12 [TCu]+0 .0 4 6 5 3[DOC]- 0 .0 80 4 5 [Cu]+0 .0 0 794 [Fe]+0 .0 36 6 [Ca],P =0 .0 0 0 0 相似文献   

蔬菜对土壤镉铜锌富集能力的研究

调查了福建部分污染严重地区不同蔬菜对镉、锌、铜的富集能力。结果表明蔬菜对镉的平均富集系数为0.017,锌的平均富集系数为0.116.铜的平均富集系数为0.014。蔬菜对镉的富集系数的品种间差异最大,达315倍,远高于锌和铜的富集系数的品种间差异。茭白、豇豆和莲藕对镉的富集能力较低,可作为镉污染土壤优先选种的蔬菜品种,而青包菜、白包菜、芥菜、空心菜、芋头等对镉的富集系数较高,不宜在镉污染土壤上栽培。     

兰格缪尔等温式的适用性分析——以黄土吸持铜离子为例

在不同土壤浓度条件下进行了黄土对铜离子的等温吸持实验（包括吸附与沉淀）。利用兰格缪尔（Langmuir）等温式对实验结果进行拟合时发现：黄土对铜离子的吸持结果在形式上仍可用传统的Langmuir等温式来描述，但式中的相关参数已经不再具有原来的物理意义。本文分析了Langmuir等温式在黄土对铜离子吸持时的适用性，指出其参数变化与铜离子的吸附关系不大，而与沉淀密切相关。     

铜陵市铜尾矿土壤动物群落生态研究

对安徽省铜陵市铜尾矿地6种生境中土壤动物群落进行野外调查和室内分析，研究不同弃置堆放时间的铜尾矿地土壤的动物群落结构及其与尾矿基质理化性质、植被状况等生境条件之间的关系。结果表明，尾矿堆放时间、区位地貌和植被状况的不同，尾矿基质的理化性质发生变化，导致土壤动物的种类组成和数量分布具有明显差异。土壤动物在土体中的表聚性强，绝大部分集中分布于A层(0～5cm)；土壤的物理性质越稳定，土壤动物越丰富；土壤肥力越高，土壤动物越丰富多样。即尾矿地土壤的生境条件越优越，土壤动物群落的物种丰富度越大，个体数量分布越多，群落多样性越高。这些研究结论为尾矿区的生态修复和可持续利用提供了参考依据。     

First-trimester diagnosis of menkes disease: Intermediate copper values in chorionic villi from three affected male fetuses

Chorionic villus samples with copper contents of 1·91, 4·2, 5·6, and 6·3 ng/mg were observed in four cases with male karyotypes. These values were outside the range for unaffected males (0·30–0·85 ng/mg), and three of them were outside the control range (0·20–2·39 ng/mg). But these three values were below the values previously observed for affected Menkes fetuses (12·0–24·8 ng/mg). Follow-up by ⁶⁴Cu uptake studies on the amniotic fluid cells was performed in three of these cases. A combination of ⁶⁴Cu uptake and chase experiments on the amniotic fluid cells showed more convincingly than ⁶⁴Cu uptake per se the direct copper values of 4·2 and 5·6 ng/mg to correspond to affected fetuses. Amniotic fluid cells from the male fetus with the CV copper value of 1·9 ng/mg showed normal results. The CV copper value of 6·3 ng/mg was considered pathognomonic for Menkes disease. The pregnancy was terminated, and the diagnosis was confirmed on fetal fibroblasts. Maternal deciduum prepared from the placentae showed in one of the cases with an affected fetus copper values ranging from 1·5 to 5·7 ng/mg. In six additional diagnostic cases, the copper content was determined in both CV samples and maternal deciduum. In three of these cases with normal CV sample copper, maternal decidua values of 4·85–7·8 ng/mg copper were observed. These results show that maternal deciduum contamination of a CV sample could cause a false-positive diagnosis.     

湘江水体中重金属的化学形态及分布特征的研究

水体中重金属的生态效应和迁移转化规律与其化学形态密切相关。本文结合湘江重金属水容量与背景值的研究,较系统地研究了铜、铅、镉和锌的化学形态及其在全江段水中的分布特征。应用阳极溶出伏安法,得到湘江水中重金属总量、溶解态含量和悬浮态含量的分配与分布特征,还有溶解态所包含的金属的主要存在形态及与之共存的其它多种形态(包括悬浮态)共十种,该文对其形成、分配和相互转化进行了综合分析。     

乌贼墨黑色素对Pb2+-Cu2+二元体系的吸附性能研究

为探索新型生物吸附剂，以乌贼墨黑色素（SIM）为吸附剂，研究Pb²⁺、Cu²⁺单组分溶液及Pb²⁺-Cu²⁺二元混合体系中SIM对Pb²⁺和Cu²⁺的吸附效果并构建等温吸附模型.结果表明，pH值、SIM添加量、吸附时间对SIM吸附Pb²⁺和Cu²⁺的吸附量影响较大，而吸附温度对吸附效果影响较小；单组分吸附与二元混合体系吸附对比表明，二元混合体系中Pb²⁺和Cu²⁺存在竞争吸附.应用L （Langmuir）和F （Freundlich）等温吸附模型拟合了SIM对Pb²⁺、Cu²⁺单组分金属离子的吸附过程，其中L模型与试验结果拟合度更高；应用Non-modified Langmuir、Modified Langmuir isotherm、Extended Langmuir、Extended Freundlich和SRS模型5种模型对Pb²⁺-Cu²⁺二元混合体系的等温吸附过程进行拟合，其中Extended Langmuir模型与试验结果拟合度最佳.应用红外光谱（FTIR）分析SIM吸附金属离子的原理时发现，SIM上羟基、-NH和不饱和键是金属离子的吸附位点，且SIM对Pb²⁺的吸附能力优于对Cu²⁺的吸附.     

炼钢废气除尘污水处理的研究

系统地研究了影响石灰中和法处理转炉除尘废水含铜沉降速度的因素.结果表明,在搅拌时间10 min和中等搅拌强度的条件下,pH值控制在8.2～9.0范围内能使废水中铜含量在1 h的沉降时间内降至国家排放标准2 mg/L以下.实验还研究了在石灰中和过程中加入适量絮凝剂的影响因素.结果表明,在搅拌时间3 min和相同pH值范围的条件下,加入絮凝剂能使废水中铜含量在30 min的沉降时间内降至国家排放标准2 mg/L以下.