排序方式: 共有21条查询结果,搜索用时 524 毫秒
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华北地台晚古生代煤中微量元素及As的分布 总被引:30,自引:2,他引:30
研究了华北聚煤盆地晚古生代煤中微量元素,并与全国和西南地区煤中微量元素含量进行了对比。还研究了煤的区域地球化学特征,在华北地台划分了3个煤区域地球化学带,绘制了山西组和太原组煤中As等元素的分布图。结果发现,除个别微量有害元素(如Ni,U,Cl,Mo,Cu,Zn)在局部地区富集外,华北聚煤盆地晚古生代煤中微量有害元素含量较低。整体上不足以对环境和人体造成危害(燃煤产物及其危害性尚值得深入研究);As的区域分布和古地理环境及煤岩煤质特征相吻合,指出华北地台晚古生煤中微量元素的分布总体上主要受控于聚煤古环境,其分布具有南北分带,东西延展的特征。 相似文献
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高分辨电感耦合等离子体质谱法测定煤质样品中49种痕量元素 总被引:1,自引:0,他引:1
Various trace elements, especially potential toxic trace elements such as As, Cd, Cr, Cu, Hg, Pb, Ni, Se, Tl, Zn, would be concentrated in processing of coal. Determination of these elements in coal is very important for identification of coal quality. A method is developed for determination of 49 trace elements in coal by high resolution inductively coupled plasma mass spectrometry (HR-ICPMS). Microwave acid digestion and low-temperature airproof acid digestion for sample preparation were investigated. It is shown that the low-temperature airproof acid digestion method is of lower blank, and more suitalbe for the coal sample preparation. The on-line internal standard (Rh) sample introduction is applied to compensate matrix effects in measurement by ICPMS. The method gives low detection limits (0.002-1.60 μg/g) and better relative standard deviations (0.60%-4.78%) for the determined 49 elements in coal. 相似文献
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Monitoring of 238U and 232Th in radiation environmental samples including water and biota was requested by the related international and national safety guides and standards. Inductively coupled plasma mass spectrometry (ICP-MS) was applicable to determination of 238U, 232Th in such samples with a high sensitivity and working efficiency. Some practical aspects are presented. 相似文献
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文章通过对大跨度重荷高架模板支撑系统的应力及变形监测的介绍和数据分析,对钢管扣件式模板脚手架系统的受力性能与施工要点进行了总结与探讨。 相似文献
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提出了一种用XRF测定复杂地质全分析样品中某些其它成分的分析方法。采用熔融法制备样片,个别元素用压片法制样,用散射内标法与经验α系数相结合的办法进行基体效应的校正。各氧化物的测定下限分别为:SrO 0.0030%,ZrO_20.0030%,PbO 0.0036%,CuO 0.0042%,NiO 0.0027%,ZnO 0.0021%,Cr_2O_3 0.0069%,BaO 0.0048%,As_2O_3 0.0015%,Nb_2O_5 0.0048%,V_2O_5 0.0051%,ThO_2 0.0036%,U_3O_8 0.0030%。其分析结果的精密度和准确度较好,能够满足地质研究工作的需要。 相似文献
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为了解决核燃料循环前端铀产品中痕量钍的分离、分析问题,将高分辨电感耦合等离子体质谱(HR-ICP-MS)与同位素稀释技术(ID)相结合,建立了灵敏、准确的八氧化三铀中微量钍的分析方法,方法的检出限为0.003 3 μg/g,相对标准偏差小于3%(n=3). 相似文献
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合肥市中级人民法院综合审判楼工程内天井院为高56.5m的屋盖格构,介绍了超高超重结构的模板支撑系统设计与施工的方法。 相似文献
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