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1.
用原子吸收法测定镉、铜、铅、锌时,每次配制一系列混合标准溶液均需一定的时间和试剂。为节约起见,对配制的镉、铜、铅、锌混合标准溶液系列进行稳定性试验,以考察其稳定时间。1 试验试验仪器、试剂和测定步骤均按文献[1]。吸取混合标准溶液各若干毫升,分别移入5个1000mL容量瓶中,用0 2mol/L硝酸定容,作放置试验,见表1。 表1 镉、铜、铅、锌系列混合标准溶液质量浓度 mg/L混合标准溶液V/mL5 0010 0030 0050 00100 00镉0 050 100 300 501 00铜0 250 501 502 505 00铅0 501 003 005 0010 0锌0 050 100 300 501 001 1 稳定性试验1 …  相似文献   

2.
研究了大气降尘中铅、锌、铜、铁等金属元素的原子吸收光谱测定方法,用氢氟酸消解法对降尘进行预处理,并对方法的精密度、准确度进行了检验,结果较为满意.该法简便、快速、灵敏.  相似文献   

3.
微分脉冲伏安法测定降水中锌、镉、铅和铜   总被引:2,自引:0,他引:2  
以量浓度为0.01mol/L的高氯酸为支持电解质,采用微分脉冲阳极溶出伏安法同时测定降水中的痕量Zn^2 、Cd^2 、Pb^2 和Cu^2 .6次测定的相对标准偏差均小于5%,降水样品镉未检出。锌、铅、铜的加标回收率分别为91.5%-110.0%、91.5%-104.0%和91.0%-106.0%。该方法应用于降水中Zn、Cd、Pb、Cu痕量元素的分析,具有方法简便、快速、准确度高等特点。  相似文献   

4.
以南京北郊为例,测量分析了屋面径流中砷(As)、汞(Hg)、铅(Pb)、镉(Cd)和锌(Zn)5种元素的浓度、形态特征。结果表明:短时强降雨过程中这5种元素浓度在较大范围内无规则波动,且不同元素间浓度分布存在较大差异;Zn与Pb的平均浓度分别高于《地表水环境质量标准》(GB 3838—2002)的Ⅴ类和Ⅳ类标准限值,污染程度从大到小依次为ZnPbAsHgCd。元素形态分析表明,径流中除Hg外其他4种元素主要以颗粒态形式存在,各元素颗粒态占总形态的平均分数分别为:As,64.5%;Hg,43.7%;Pb,76.5%;Cd,54.6%;Zn,54.3%。  相似文献   

5.
一次微波消解测定土壤中铬铜锌铅镉   总被引:2,自引:0,他引:2  
测定土壤中铬、铜、锌、铅、镉多采用传统电热板加热消解方式进行样品处理,但不能同时一次消解.笔者尝试使用微波一次消解测定五种元素,试验结果令人满意.  相似文献   

6.
习霞  明亮 《中国环境监测》2011,27(3):32-34,41
通过多壁碳纳米管-Nafion复合膜修饰电极,建立水样中痕量铅、镉、铜、锌同时测定的线性扫描溶出伏安分析法,优化支持电解质及pH值、修饰剂用量、富集电位及时间等测定条件。实验结果表明,在pH 4.0的NaAc-HAc缓冲液中,-1.20V富集5min后,在电位-1.04V、-0.72V、-0.45V及-0.16V附近分别产生锌、镉、铅、铜的灵敏溶出峰,测定各元素的线性关系良好,相对标准偏差均小于5.4%。该法已成功应用于实际水样中痕量铅、镉、铜、锌的同时测定,加标回收率在93.3%~106.7%之间,结果满意。  相似文献   

7.
蔬菜与土壤环境中铅镉含量相关性调查   总被引:6,自引:0,他引:6  
通过调查5种蔬菜对铅、镉绝对吸收量以及富集系数不同,分析了蔬菜与土壤中重金属含量相关性.结果表明,各种蔬菜对镉的吸收绝对量差异明显,同类型蔬菜对铅、镉的吸收量接近.各种蔬菜对铅的富集能力排序为白菜>黄瓜>番茄>青菜>辣椒,对镉的富集能力排序为青菜>白菜>辣椒>番茄>黄瓜.蔬菜对土壤中镉的吸收能力明显大于铅.  相似文献   

8.
为研究湘江大源渡枢纽底泥中Cd、Pb的污染特征及其生态风险,采集6个断面的18个底泥样品,测定了沉积物中Cd、Pb的总量、化学形态及其生物有效性,并利用地积累指数法和单因子指数法评价其污染程度与等级.结果表明,湘江大源渡枢纽底泥中Cd、Pb存在很强的积累现象,尤其是Cd污染特别严重.各采样点底泥中Cd主要以碳酸盐结合态...  相似文献   

9.
污染底泥粒径分析与铜、锌吸附特性的研究   总被引:1,自引:0,他引:1  
该研究通过对矿区选矿废水污染河流的底泥进行采样分析,探讨了底泥粒径与质量分数的关系及其铜、锌的吸附特性。结果表明,底泥中各粒径质量分数在垂直方向上无明显区别,但粒径间有显著的区别,其质量分数可分为3种类型。铜、锌吸附量随着污染底泥粒径的变小而增加,呈负相关关系,且锌吸附量与粒径间的这种负相关关系达到显著性水平。底泥中铜、锌吸附贡献率具有相似的特性,两条贡献率曲线几乎是重合的,呈"双峰型",最大吸附贡献率出现在粒径中值0.375mm处,粒径中值0.605mm处有一低谷。特别要强调的是,河流底泥铜、锌污染严重,清理底泥使河流免遭二次污染十分必要。  相似文献   

10.
兰州市小儿血铅水平与环境铅污染关系调查   总被引:6,自引:0,他引:6  
采用随机抽样的方法对兰州市103对新生儿及其母亲、1月至36月的146名婴幼儿以及808名3~7岁儿童的毛细血管血铅进行了分析,同时对上述幼儿园室内外尘土或土壤样品采用石墨炉原子吸收法进行了铅分析测定,通过相关分析,说明城市环境铅污染是小儿血铅升高的主要原因之一。  相似文献   

11.
南通市某钢丝绳行业集中区降尘中重金属污染状况评价   总被引:1,自引:1,他引:0  
针对南通市钢丝绳行业集中区重金属污染问题,分析降尘中的铅、镉、铬、铜、镍、铁、锌、锰等重金属含量,并采用污染指数法和地累积指数法对降尘中重金属污染状况进行评价。结果表明,该集中区降尘中重金属污染程度依次为Zn>Pb>Cd>Cu>Fe>Mn>Ni>Cr,铅、锌为主要污染因子,铅、锌污染级别均处于重污染级别。  相似文献   

12.
以钢丝绳产业集聚区内的土壤为研究对象,采集和分析产业区中心河两边淹水环境下的水稻田、少用受污染河水灌溉的棉花田及不用受污染河水灌溉的蔬菜地样本,结果表明,产业区内土壤中铅和锌的含量明显高于产业区外。产业区内除水稻田土壤中铅的质量比超过评价参比值外,其他灌溉方式下土壤中铅和锌的质量比均未超过《土壤环境质量标准》(GB 15618-1995)中的二级标准(pH值>7)。统计分析表明,土壤中的重金属含量与废水灌溉方式有关,该产业区内土壤外源重金属来自钢丝绳产业的可能性很大。在不同的灌溉方式下,土壤剖面样品中的重金属含量随着土壤深度增加呈现降低的趋势,2010年和2011年的测定结果无显著差异。  相似文献   

13.
In the environment of a lead smeltery contamination with lead, zinc and cadmium was measured over a 15-year period. Efficient bag filters were installed in order to remove dust from the flue gases. This measure of improvement resulted in a drastic reduction of lead, zinc and cadmium content in suspended particles (by 92, 94 and 89%), to a lesser extent in depositions (by 79, 75 and 68%), whereas in household dust the reduction was considerably lower (by 53, 55 and 70%). It can be assumed that household dust contains also redispersed soil particles on which the dust from the smeltery flue gases has deposited over years. To determine to what extent contaminated soil continues to cause increased population exposure directly or through plants or pastures, in the period 1981–1985 the content of metallic ions in the soil was measured at three depths. Selective solubility of soil metallic compounds was analysed in water, in 1 mol ammoniumacetate solution and in 0.05 mol ethylenediaminetetra-acetic acid (EDTA) solution in relation to their solubility in suspended particles, depositions and household dust. A considerably low portion of soluble metallic compounds was found in the soil and physico-chemical characteristics of the soil and portion of metallic ions bound to fulvice and humic acids were determined. The behaviour of metallic ions in contact with soil samples was studied in laboratory and it was found that approximately 50% of lead, 70% of zinc and 7% of cadmium ions change into non-soluble or poorly soluble compounds. By qualitative phase analysis in the non-soluble fraction PbO2, Pb3P4O13, Zn(OH)2, ZnO, Fe2O3 and Cd(OH)2 were identified.  相似文献   

14.
根据重庆市城市组团式建设特点,采用径迹法对重庆市主城建成区开展室内氡浓度调查。结果表明,各区县室内氡浓度整体水平较低,重庆市主城区室内氡浓度平均值为64.5 Bq/m3,168个采样点均小于国家标准200 Bq/m3;吸入氡及子体对人员产生的年均有效剂量均低于《住房内氡浓度控制标准》和《地下建筑氡及其子体控制标准规定》中规定的室内氡浓度行动水平。  相似文献   

15.
南通地区很多钢丝绳企业采用酸洗磷化工艺,产生大量含铅、铁、锌等重金属离子的酸性废液,造成区域特征性环境污染.选用山东天维膜技术有限公司的扩散渗析阴膜进行钢丝绳酸性废液处置实验.结果表明:该膜能有效地将酸、盐分离,酸的回收率达到90%以上,铅截留率达到70%以上,铁截留率达到80%以上.但实验中出现氯化铅晶体析出,堵塞处...  相似文献   

16.
The aims of this study were to determine the contents of cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn), aluminium (Al), and iron (Fe) (aqua regia-extractable) in 27 soil plots (54 samples) from Manresa, NE Spain, and to establish relationships between heavy metals and some soil properties. The main soil types were surveyed and the median concentrations (mg kg(-1)) obtained were Cd 0.28, Cu 20.3, Pb 18.6, Zn 67.4, Al 22,572, and Fe 21,551. Element concentrations for these soils were lower than the published values for the Valencia region (Spain) and Torrelles and Sant Climent municipal districts (Catalonia, Spain). In terms of soil properties, the results of this study suggest that, in Manresa soils, both trace element adsorption and retention are influenced by several properties such as clay minerals, carbonates, organic matter, and pH. All element contents were positively correlated with clay content. Pb and Zn were negatively correlated with pH and CaCO(3).  相似文献   

17.
用电感耦合等离子体原子发射光谱法(ICP-AES)测定了60例世居澜沧地区拉祜族老人发样中6种微量元素,根据测定结果,比较了不同年龄段间微量元素的差异,并与北京西城区长寿老人发样中微量元素含量进行了比较。结果表明,2个地区老人发样中的Mn,Al存在显著性差异。  相似文献   

18.
渭河干流(宝鸡段)表层沉积物Cu、Zn、Pb污染特征与评价   总被引:5,自引:2,他引:5  
对渭河干流(宝鸡段)表层沉积物中重金属Cu、Zn、Pb含量进行了调查,用潜在生态危害系数法对其污染水平进行了评价,并与松花江(吉林市段)、淮河(江苏段)、长江(下游)、苏州河、珠江(广州段)5条河流表层沉积物中Cu、Zn、Pb的含量做了对比研究。结果表明,3种重金属元素平均含量均超出相应的土壤背景值,出现了一定程度上的富集;生态危害系数均〈40,属轻微生态危害。重金属含量水平在国内诸河中处于中间位置。  相似文献   

19.
This study was conducted to investigate the pollution load index, fraction distributions, and mobility of Pb, Cd, Cu, and Zn in garden and paddy soils collected from a Pb/Zn mine in Chenzhou City, China. The samples were analyzed using Leleyter and Probst’s sequential extraction procedures. Total metal concentrations including Pb, Cd, Cu, and Zn exceeded the maximum permissible limits for soils set by the Ministry of Environmental Protection of China, and the order of the pollution index was Cd > Zn > Pb > Cu, indicating that the soils from both sites seriously suffered from heavy metal pollution, especially Cd. The sums of metal fractions were in agreement with the total contents of heavy metals. However, there were significant differences in fraction distributions of heavy metals in garden and paddy soils. The residual fractions of heavy metals were the predominant form with 43.0% for Pb, 32.3% for Cd, 33.5% for Cu, and 44.2% for Zn in garden soil, while 51.6% for Pb, 40.4% for Cd, 40.3% for Cu, and 40.9% for Zn in paddy soil. Furthermore, the proportions of water-soluble and exchangeable fractions extracted by the selected analytical methods were the lowest among all fractions. On the basis of the speciation of heavy metals, the mobility factor values of heavy metals have the following order: Cd (25.2–19.8%) > Cu (22.6–6.3%) > Zn (9.6–6.0%) > Pb (6.7–2.5%) in both contaminated soils.  相似文献   

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