共查询到20条相似文献,搜索用时 93 毫秒
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原子吸收分光光度法直接测定汞触媒中氯化汞含量 总被引:1,自引:0,他引:1
国家标准中测定汞触媒中氯化汞含量时需要破碎汞触媒的样品。汞触媒载体是条状活性炭,破碎及收集处理样品时产生大量含汞粉尘,污染环境。许多PVC生产厂需要检测汞触媒质量时,一般将其送至生产厂进行检测,非常不便。另外,检测时还需使用专用仪器设备将汞灼烧出来,然后采用滴定法测定,操作复杂,时间长。本文介绍的方法无需破碎汞触媒样品,就可以检测汞触媒中氯化汞的含量。 相似文献
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采用盐酸-硝酸-氢氟酸-高氯酸消解预处理土壤样品,结合工作曲线法和标准加入法测定土壤中总铬的含量。结果表明,该法与国标方法比较,提高了测定样品的准确度和精密度,完全能满足环境土壤中总铬测定的要求。 相似文献
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一种测定硫酸根的直接分光光度法 总被引:5,自引:0,他引:5
新偶氮染料1,3-N,N′-双-[4-(4′-硝基苯偶氮)苯基]异方酸二酰胺(BNBPS)的DMSO溶液与适量水所构成的体系是硫酸根的良好显色剂(Δλ=102nm)。显色剂与硫酸根在pH4.3~7.5范围内发生反应,迅速由红色变为蓝色。λmax=632nm,ε632=4×104L·mol-1·cm-1,测定硫酸根的线性范围为0~15μg/10mL。考察了常见离子的干扰情况,提供了一种新的测定硫酸根的直接分光光度法,用于测定水样中的硫酸根含量,结果满意。 相似文献
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C. M. Tseng H. Garraud D. Amouroux O. F. X. Donard A. de Diego 《Journal of Automated Methods and Management in Chemistry》1998,20(4):99-108
This paper describes rapid, simple microwave-assisted leaching/ digestion procedures for total and mercury species determination in sediment samples and biomaterials. An open focused microwave
system allowed the sample preparation time to be dramatically reduced to only 24 min when a power of 40-80 W was applied. Quantitative leaching of methylmercury from sediments by HNO3 solution and complete dissolution of biomaterials by an alkaline solution, such as 25% TMAH solution, were obtained. Methylmercury compounds were kept intact without decomposition or losses by evaporation. Quantitative recoveries of total mercury were achieved with a two-step microwave attack using a combination of HNO3 and H202 solutions as extractant. The whole pretreatment procedure only takes 15 min, which can be further shortened by an automated robust operation with an open focused system. These analytical procedures were validated by the analysis of environmental certified reference materials. The results confirm that the open focused microwave technique is a promising tool for solid sample preparation in analytical and environmental chemistry. 相似文献
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光度法直接测定水溶液中微量汞的分析方法研究 总被引:1,自引:0,他引:1
在表面活性剂聚乙二醇辛基苯基醚TritonX-100和乙醇存在下,研究了双硫腙与水中Hg2 的显色反应,建立了简便、环保的水相中直接测定痕量Hg2 的分析方法——双硫腙水相光度法。在pH<2时该体系与水中Hg2 形成有色络合物,其λmax=495nm,在5~60μg/L范围内,吸光度与Hg2 含量成线性关系,相关系数为0.9995,摩尔吸光系数ε=4.7×104L/(mol.cm)。该方法的相对标准偏差和相对误差均小于双硫腙萃取光度法(国标法)。用活性炭粉末富集后检测下限可达1μg/L以下,铜离子有干扰。 相似文献
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By use of oxygen flask combustion (OFC), a rapid and convenient determination method for mercury (Hg) and sulfur (S) in coal was developed. For the determination of Hg in coal, the OFC method with a KMnO4 solution as an absorbent was carried out, and the resulting solution was analyzed by cold vapor atomic fluorescence spectrometry (CVAFS). For six certified reference material coals, the Hg concentrations obtained by this method were in good accordance with the certified or reference values. In addition, nine brands of Japanese standard coals (SS coals) were analyzed by the present method, and the data were compared to those from the authentic microwave-acid digestion (MW-AD) method. For the determination of total S in coal, the OFC method with H2O2 solution as an absorbent followed by ICP-AES or precipitation titration was successfully applied. 相似文献