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1.
微波消解ICP-AES法测定土壤及底泥等中常量及微量元素   总被引:16,自引:0,他引:16  
建立了电感耦合等离子体发射光谱法同时测定土壤及底泥等中的铜、铅等多元素方法,采用水平及垂直双向观测,提高了分析灵敏度。对ICP工作参数选择、酸度对测定的影响、元素分析线选择、元素间光谱干扰校正系数的确定以及背景扣除方式等进行了研究。该方法线性范围宽,精密度及准确度较好,检出限低,多元素同时分析,分析速度快,操作简便。用于实际样品的测定,结果满意。  相似文献
2.
提出了沸水浴混合酸法消解,以异丙醇为增感剂,电感耦合等离子体质谱直接测定土壤和沉积物中硒的方法。实验表明2mol/L硝酸-4mol/L盐酸混酸能有效溶出土壤和沉积物中各种形态的硒。相对于1%硝酸基体,4% (V/V) 异丙醇基体中硒的ICP-MS响应值提高了12.1倍;而且4% (V/V) 异丙醇基体可有效抑制硒的质谱干扰。ICP发射功率和雾化气流速是影响异丙醇在ICP-MS测定过程增敏效应的主要因素。以78硒为测定同位素,方法检出限为0.005mg/kg,实际样品测定精密度均小于5%。用于测定土壤和沉积物国家标准样品并对其消解液进行加标回收实验,结果令人满意。  相似文献
3.
介绍一种悬浮液进样直接测定土壤、底泥中多种微量金属元素的快速分析方法。基体改进剂的使用,适宜的原子化温度的选择,使用水相标准溶液作校准曲线成为可能.对标准作品的测定证明了此方法的精密度和准确度较好,适合于常规环境样品分析.  相似文献
4.
微波消解-ICP-MS测定土壤和底泥中的12种金属元素   总被引:1,自引:1,他引:0  
以20.0μg/L铟作内标,采用硝酸-氢氟酸-过氧化氢体系微波消解,ICP-MS(电感耦合等离子体质谱法)同时测定土壤和底泥中的12种金属元素,各元素方法检出限为0.003~0.2μg/g,相对标准偏差小于6.1%,土壤标准样品的测定值与标准值吻合。方法简便快捷,灵敏度高,重现性好,是分析大批量土壤和底泥样品中多元素的可靠、高效方法。  相似文献
5.
顶空气相色谱法测定土壤或底泥中挥发性苯系物   总被引:1,自引:0,他引:1  
采用顶空气相色谱法测定了土壤或底泥中的挥发性苯系物,测定了苯系物在10%NaCl水溶液60℃时的分配常数,给出了加入土壤导致液相体积改变的校正方法。用10% NaCl水溶液作为提取剂在 60℃加热平衡60min, 对5个苯系物的平均回收率达到73.6%, 检出限为4.2~5.5ng/g。  相似文献
6.
采用吹扫捕集-气相色谱质谱法对土壤和沉积物中挥发性有机物进行分析,优化了实验条件,所有物质的相对标准偏差小于5.0%,土壤样回收率在78.2% ~99.8%之间,沉积物样的回收率在55.2%~95.2%之间.  相似文献
7.
土壤和沉积物中多氯联苯单体测定的净化方法研究   总被引:1,自引:0,他引:1       下载免费PDF全文
对浓硫酸净化、铜粉脱硫、氟罗里硅土柱、硅胶柱、石墨碳柱等净化方法在土壤和沉积物多氯联苯单体测定中的应用进行了研究。浓硫酸对多氯联苯单体的净化回收率达92.4%~109%;氟罗里硅土柱用正己烷/丙酮混合溶液淋洗,净化洗脱液体积为8 mL~10 mL时,回收率达85.7%~108%;硅胶柱用正己烷淋洗,净化洗脱液体积为8 mL~10 mL时,回收率达81.2%~107%;石墨碳柱用甲苯淋洗,净化洗脱液体积为12 mL时,回收率达93.5%~112%。将优化后的净化方法应用于实际样品测定,精密度与加标回收率均良好。  相似文献
8.
Hazardous waste sites may pose a threat to human health and the environment when toxic substances are released. However, the contaminants present at a waste site may have originated on-site (i.e., resulting from releases attributable to site activities) or off-site (i.e., resulting from sources not on-site). Off-site substances may result either from natural sources (e.g., erosion of naturally occurring mineral deposits) or anthropogenic sources (e.g., widespread contamination from automobile exhaust in urban areas). To determine the appropriate action to take at a hazardous waste site, the U.S. Environmental Protection Agency (EPA) must distinguish between substances directly attributable to the hazardous waste site (i.e., site contaminants) and those attributable to natural background concentrations. The most important factor to consider when determining background concentrations is to ensure that the physical, chemical, and biological aspects of the media to be sampled at both the contaminated site and the background site are as similar as possible. Inorganics, in particular metals, are addressed. Radionuclides are not specifically addressed; however, metals with radioactive isotopes that may be encountered at hazardous waste sites are included. There are references and data included in this paper that provide average concentrations and reference values for selected soils and sediments in the United States. Suggested sampling and monitoring design approaches that could be used by scientists and engineers faced with how to determine background concentrations are identified. The issues discussed include the selection of background sampling locations, considerations in the selection of sampling procedures, and statistical analyses for determining whether contaminant levels are significantly different on a potential waste site compared with a background site.  相似文献
9.
The relationship between alder (Alnus japonica) distribution and surrounding land use in Kushiro Mire was spatially assessed using remotely sensed imagery. From the result, it was found out that the expanding area of alder trees in Kushiro Mire was affected by the agricultural land area in the upper course of the river basin and flooding in the lower course of the river. The soil sediments flowing into the Kushiro Mire from the agricultural land resulted in heavy sedimentation that favors the growth of alder trees. Consequently, the number and density of alder trees has increased. The future distribution of alder trees was predicted based on the mechanism of expansion of the alder-tree area in Kushiro Mire, and it was found that large vegetation areas in Kushiro Mire will be changed to areas with alder trees.  相似文献
10.
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