共查询到19条相似文献,搜索用时 31 毫秒
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建立了DMA-80型汞分析仪直接固体进样测定粗制氧化锌中汞的方法。试样经干燥和高温分解处理,采用催化分解和吸附净化使分解产物转变为氧化汞蒸气,通过金质汞齐化器还原并以金汞齐形式被捕集,最后在波长253.65 nm处进行原子吸收测量,依据朗伯-比尔定律定量。优化了干燥时间和温度、分解时间和温度等实验条件,同时做了方法检出限、精密度、回收率等实验。结果表明:方法检出限为0.015 ng,线性范围为0.02~100 ng,相关性系数≥0.999,回收率为93.2%~102.7%,精密度(RSD,n=7)≤5.0%,可用于进口粗制氧化锌的快速检验。 相似文献
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《应用化工》2022,(8)
建立DMA-80直接测汞仪测定生物质燃料中汞含量的方法,考察了分解温度和分解时间对测定汞含量的影响,还研究了该方法的准确度和精密度。结果表明,分解温度为550℃和分解时间为80 s时,样品完全分解,检测结果稳定。汞含量在220 ng范围内,峰高和汞含量线性关系良好,用标准加入法进行回收率实验对方法的准确度进行考察,相对标准偏差为0.74%20 ng范围内,峰高和汞含量线性关系良好,用标准加入法进行回收率实验对方法的准确度进行考察,相对标准偏差为0.74%1.51%,加标回收率为100.62%1.51%,加标回收率为100.62%101.43%。与其他检测方法比较,该方法无需前处理、操作简单、检测时间短、系统误差小,不仅减少样品处理过程中的误差,同时还减少化学试剂对环境的影响,是值得推广的一种方法。 相似文献
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本研究尝试建立利用热分解-汞齐化富集-冷原子吸收分光光度法测定工业废盐中汞含量的方法。本研究方法在进样量为0.1g,样品干燥温度为150℃,干燥时间为20s,热分解温度为750℃,分解时间为180s,汞齐化时间为12s,读数时间为30s的条件下用直接测汞仪检测工业废盐中的汞含量。实验结果显示,方法测定范围为0.001μg/g~5μg/g,相关系数R2优于0.9999,汞含量的检出限为0.0002μg/g,相对标准偏差(RSD)在6.34%~7.55%范围内,工业废盐样品加标回收率在89.8%~121.4%范围内。该方法操作简便、耗时较短、无基体干扰、重现性好、准确度高,适用于生态环境损害鉴定评估、固体废物鉴别等工作中工业废盐的汞含量测定。 相似文献
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建立了一种测定山药中有害元素汞、砷的新方法。主要对样品的前处理过程进行了研究,比较了微波消解法和浸提法的实验结果。采用氢化物发生-原子荧光法测定,对仪器条件、酸度、KBH4浓度和预还原剂进行了优化。结果表明:微波消解法和浸提法的测定结果没有显著差异。利用本方法测汞、砷的线性范围分别为0~50ng/mL、0~100ng/mL,汞、砷的检出限分别为0.005ng/mL、0.087ng/mL,对4ng/mL汞和20ng/mL砷,相对标准偏差分别为2.13%和3.92%。汞回收率在94.8%~102.9%、砷回收率在91.5%~105.7%。 相似文献
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目的:探讨用自动测汞仪直接对对海鱼中总汞含量进行测定。方法:用自动测汞仪直接测定海鱼中总汞和用国家标准测汞仪法分别进行样品的检测。结果:对两种方法的实验结果进行比较,经配对t检验t9=0.67,t(0.05,9)=2.26,即t9t(0.05,9),结果表明差异无显著性(P0.05),回收率在95.5%~100%之间,检出限为0.009 ng;测定国家环境标准参考物质(GSBZ202031),测定值均在标准值范围内。结论:测汞仪直接测定总汞方法的建立与研究,并在海鱼中总汞含量的应用;具有快速﹑简便﹑准确和省时的特点,适合大批样品的检测与日常监督。 相似文献
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O.J. Whittemore 《Powder Technology》1981,29(1):167-175
Mercury porosimetry has been used in ceramics for the characterization of products and for studies of processing. Specifications including PSD (pore size distribution by mercury porosimetry) are now applied to magnesia refractories used in basic oxygen furnaces and to building brick which may be exposed to frost. Other products cited as examples are the silica fiber tile used on the space shuttle, plasma sprayed coatings, carbon composites and filters.In ceramic processing research, PSD has proved valuable for evaluating the firing of basic refractories, brick and sanitary ware. Pore growth during the early stages of sintering several materials was first identified by PSD. The character of clay agglomerates and the presence of alumina aggregates in compacts have been measured, the latter showing bimodal PSD. The progressive change in PSD while compacting glass spheres outlines the stages of compaction. The most frequent pore diameter in plaster slip casting molds correlates directly with plaster consistency.In dense or vitrified ceramics, errors may occur due to closed pores or pores with narrow openings. However, in ceramic compacts and highly porous ceramics, pores have several openings so PSD is a realistic measure of structure. 相似文献
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Mercury release from FGD 总被引:1,自引:0,他引:1
The release of mercury from flue gas desulfurization (FGD) gypsum in the manufacture of 100% FGD wallboard was studied. Calcination, with product temperatures ranging from 150 to 180 °C, appears to be the most likely process to release mercury from the FGD. Two samples evaluated in trials conducted to simulate the calcining of FGD in flash calcining and kettle processes showed that the potential of mercury release exists. The differing amounts of mercury released by the two processes could be separated by orders of magnitude. Measurements in real production facilities are essential to developing a valid answer to the question of mercury release during FGD gypsum wallboard production. 相似文献
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The literature on the use of mercury porosimetry in pharmaceutical technology is reviewed. The relation between the application and the preferable pore size distribution presentation is also discussed. In addition, pore size distributions of lactose tablets are presented and the calculated values for the porosity, pore diameter and specific surface area are compared with results from air permeability and nitrogen adsorption measurements. The agreement is acceptable taking into account the simplifications and the inaccuracy of the methods. 相似文献