直接测汞仪测定涂料中的可溶性汞

文章采用直接测汞仪对涂料样品进行了可溶性汞含量的分析测定.通过正交试验法对干燥温度、干燥时间、分解温度、分解时间等条件进行了优化,并进行了线性关系、精密度、回收率等实验.结果表明,本方法线性范围0～500 ng,相关系数大于0.9994,检测低限为 0.015ng,回收率在97.1%～101.0%之间,相对标准偏差小于...     

直接测汞仪测定粗甘油中微量汞

利用热解析冷原子吸收光谱汞直接测量法对粗甘油中微量汞含量进行检测,结果表明:检出限0.004 7μg/kg;相对标准偏差1.7%;加标回收率为99.9%~103.5%,该方法具有良好的精密度与准确度,适用于粗甘油中微量汞的测定。     

直接测汞仪测定粉状化妆品中的总汞

采用直接测汞仪对粉状化妆品总汞含量的快速分析方法。通过实验对干燥温度、干燥时间、分解温度、分解时间等条件进行优化,并进行了线性关系、回收率、精密度、方法比对等实验。结果表明,本方法线性范围(0~400)ng,相关系数r2≥0.9990,检出限0.01 ng,相对标准偏差小于3%,回收率在98.4%~104.4%之间。本方法灵敏度高,简便、快速、准确,适用于粉状化妆品总汞的测定。     

自动测汞仪直接对海鱼中总汞进行测定的探讨

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。     

含汞废水处理

对比了几种汞处理的方法,通过实验室分析总结采用硫化钠沉淀含汞废水效果较好。实验数据结果表明,出水中汞的含量小于国家规定的排放标准沉渣体积小且化学稳定性很好,易处置。此法具有反应速度快,沉淀效率高,可连续处理和间歇处理,处理费用低等优点,该法可在中小型化工厂中推广应用。     

Mercury porosimetry of ceramics

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.     

Mercury release from FGD

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.     

Mercury porosimetry in pharmaceutical technology

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.     

高纯汞的快速测定

<正> 高纯汞的检验,一般按国家标准GB913-66中的检验方法(下称国标法)进行,即先将汞蒸馏分离,用重量法测定残渣,然后用差额法计算出汞的含量,此法费时和污染环境;也有采用测定杂质的方法,但需要高级设备;若用化学法测定杂质,更繁琐费时,不适于中小型厂矿化验室的使用。我们通过实验,拟定了快速、简便、准确的方法,经多年的生产实践,结果表明效果良好。     

Mercury elimination from gaseous streams

The elimination of mercury vapours from gaseous streams has been studied using sulfurized silicates as adsorbents. A new method to sulfurize the materials based in hydrogen sulfide oxidation at low temperature is proposed. The sulfur produced in the reaction is deposited on the material, its dispersion depending on the process temperature and physico-chemical properties of the silicates used. The adsorbents were tested in static and dynamic systems for mercury depuration of gaseous streams. Commercial sulfurized active carbon was used as a reference. X-ray diffraction, atomic absorption spectroscopy, X-ray photoelectron spectroscopy, nitrogen adsorption-desorption and mercury intrusion porosimetry were used in raw materials and adsorbents characterization.     

玉米根系土壤中汞的变化

采用根系箱试验和连续化学萃取法,结合氢化物原子吸收光谱法,研究了玉米根系土壤中各种汞的形态变化。结果表明,在玉米生长45天内,根系土壤中汞的形态有了较为明显的变化。从土壤加汞量对玉米的影响来看,土壤中汞污染程度越大,其在玉米中的积累越多,生物毒性更强,对环境的危害越大。     

汞的环境地球化学研究进展

汞俗称水银,属于全球性的污染物之一。为了减少汞排放和产品的使用,使其控制在一个可控的范围内,于2013年10月在日本的水俣市签订了汞国际使用条约。分别对大气汞、水生生态系统汞和人体汞暴露的危害等方面对汞的地球化学进展进行了分析研究。     

水泥工业控汞措施

水泥工业汞排放具有总量大、浓度低,地区间排放差异大,水泥窑生产运行期间变化大等特点.水泥工业是全球第四大汞排放行业,其汞排放在全球的占比超过其温室气体排放的全球占比.我国水泥业汞排放量占全球同行的49%,占全国总量的15%,随着《关于汞的水俣公约》的生效,我国水泥工业控汞压力日益增大.控汞工作是水泥工业的新课题,本文从汞产生、窑内循环和排放机理分析入手,总结国际控汞经验,综述和对比国内外汞排放防治技术,提出我国水泥工业控汞思路和目标,为我国制定行业履约对策提供参考.     

Mercury removal from hydrogen gas streams

Type 13X molecular sieve and chromic acid on silica gel have been examined as sorbents for the removal of mercury vapour from hydrogen at atmospheric pressure and, chiefly, ambient temperature. The molecular sieve had a very low capacity for mercury. Chromic acid on silica gel had a much higher capacity but this was much reduced by the presence of water vapour in the hydrogen.