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电感耦合等离子体发射光谱法同时测定铅锌矿中银铜铅锌 总被引:4,自引:3,他引:1
采用盐酸-硝酸-硫酸混合酸分解样品,全谱直读电感耦合等离子体发射光谱法同时测定铅锌矿石中的银、铜、铅和锌。基于改善和提高测定结果准确度和精密度的要求,分析了溶液稀释因子和酸度等实验条件对测定结果的影响。结果表明,当溶液的稀释因子为1000,盐酸的体积分数在5%~10%时,测定结果最佳。采用内标法,通过加入钴内标测量分析谱线的相对强度,抵消了由于实验条件的波动引起的影响。方法检出限银为1.96μg/g,铜为6.00μg/g,铅为9.00μg/g,锌为3.00μg/g,精密度(RSD,n=10)为1.41%~7.50%。方法经国家标准物质分析验证,测定值与标准值相符,结果准确可靠。 相似文献
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等离子体质谱法直接测定地球化学样品中金铂钯 总被引:19,自引:0,他引:19
建立了王水分解地球化学样品报直接用等离子体质谱法测定Au、Pd和Pt的分析方法。方法测定下限为Au4,0ng/g,Pd3.6ng/g,Pt2.4ng/g,方法精密度(RSD,n=12)为Au14.2%,Pd3.6%-5.2%,Pt6.6%-10.8%,三个元素的线性范围都为0.02-300μg/L。采用文中制定的分析方法直接测定了国家一级地球化学标准物质中的Au、Pd、Pt,在测定下限以上的测定结果与标准值吻合。 相似文献
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砂岩型铀矿中铀的平均含量为635μg/g,而铼的含量仅为0.3~1.9μg/g,由于铼的含量低,准确测定高含量铀矿样中的低含量铼仍是分析化学的一个难题。本文建立了电感耦合等离子体质谱法测定砂岩型铀矿中痕量铼的方法。样品经过氧化镁烧结,热水浸提以及采用103Rh作内标元素等方式消除了铀、钼及其他基体元素对测定铼的干扰。在最佳条件下,痕量铼的检出限可低至0.12 ng/g,回收率达99.8%。本方法通过多种标准样品验证,铼的测定值与标准值吻合,对铼含量在0.06~180.57μg/g范围内的实际样品进行测定,相对标准偏差均小于1.5%,能够满足砂岩型铀矿等高含量铀矿中痕量铼的测定需求。 相似文献
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电感耦合等离子体光谱/质谱法测定环境样品中的硼 总被引:7,自引:3,他引:7
采用HF-HNO3-H3PO4-HClO4密封溶样处理样品,电感耦合等离子体光谱/质谱法(ICP-AES/MS)测定农作物、膳食和粪便中的硼。所拟定的方法在测硼的同时,还可测定Cr、Cu、Li、V、Co、Zn、Sr、Cd、Ba、K、Na、Fe、Mn、Zn元素,可以为农作物和饮食中痕量元素研究提供参考。ICP-AES测定硼的方法检出限(3σ)为0.0063μg/mL,测定限(10σ,DF=100)为2.10μg/g;ICP-MS测定硼方法检出限(3σ)为0.0228ng/mL,测定限(10σ,DF=1000)为0.092μg/g。方法经植物国家一级标准物质GBW07602~07605验证,测定值与标准值接近,样品10次测定的RSD<10%。 相似文献
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采用石墨炉原子吸收光谱法,以4%NH4NO3消除干扰。测定水样中的锂。试验了影响测定的主要因素。在优化实验条件下,方法的检出限为0.27μg/l,特征量为4.2pg,锂的质量浓度为0μg/l~30μg/l时,工作曲线线性关系良好。对于ρ(Li)=20.0μg/l样品的测定相对标准偏差(RSD,n=12)为3.03%。 相似文献
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海南尖峰岭岩体热液锆石U-Pb定年及微量元素研究: 对热液作用及抱伦金矿成矿时代的限定 总被引:4,自引:0,他引:4
海南抱伦金矿矿区尖峰岭岩体中的锆石可分为岩浆锆石和热液锆石.岩浆锆石无色、透明, 长柱状、无明显包裹体, U、Th含量多小于1000μg/g, 206Pb-238U年龄加权平均值为240±2.1Ma, 代表了尖峰岭岩体的结晶年龄.热液锆石呈褐色、浑浊、半透明的自形短柱状, 相对于岩浆锆石具有异常高的U、Th及微量元素含量, 其U含量最高可达30000μg/g, Th含量最高可达20000μg/g, 微量及稀土元素含量比岩浆锆石普遍高一个数量级, 且具有较高的普通Pb.LA-ICP-MS锆石U-Pb定年结果表明, 这些热液锆石的形成年龄为106~120Ma之间, 206Pb-238U年龄加权平均值为112.8±4.3Ma, 代表了热液作用的年龄, 显示该区在112~120Ma左右经历了一次强烈的热液作用, 可能与该区燕山期大规模的岩浆作用以及抱伦金矿的成矿有关.研究还表明, 对热液锆石直接进行微区原位U-Pb定年, 可用来准确测定热液作用的时间和限定热液成因金矿床的成矿时代. 相似文献
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Michael P. Labare Michael A. Butkus Dawn Riegner Nick Schommer Jason Atkinson 《Environmental Geology》2004,46(6-7):750-754
An investigation to characterize the extent and speciation of lead contamination in water, soil, and surrounding biota was conducted at a small-arms firing and skeet range in West Point, New York. Specifically, lead concentrations were examined in sediment, soil, water, plants, fish and invertebrates. There is an elevated concentration of lead in the soil and sediment up to 11,000 g/g and 340 g/g and also evidence of bioconcentration of the lead by the surrounding biota. Earthworms had up to 90% higher concentrations of lead while tadpoles showed 20% higher concentrations compared with their controls. Lead uptake by indigenous plants gave varying results. Two species bioconcentrated lead 20 and 55 times greater than the control plants. These differences were significant (P <0.05 level) when tested by the students t test. Further studies show that the total leachable lead was highest in the invertebrates and vertebrates but not in the plants. 相似文献
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采用烘干法和冻干法分别对深圳土和重塑膨润土进行干燥制样,利用压汞试验得到的累积进汞量曲线,对土体进行了孔隙尺度划分,分析了土体采用不同温度烘干和冻干法干燥制样后孔隙分布存在的差异性,得出了制备压汞试验用土样时,冻干法优于烘干法这一结论。 相似文献
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La-Ce法岩石标准物质和Ce同位素标准溶液研制 总被引:3,自引:0,他引:3
报道了La-Ce法岩石标准物质的研制结果。标准物质选自峨眉山玄武岩中的新鲜微晶玄武岩(编号EQB),具有间隐结构,矿物组成相对均一。岩石经粉碎和均一化加工,成为粉末后分装成1000小瓶。经均匀性和稳定性检验合格后,对该岩石标准物质的Ce同位素比值和La、Ce元素含量进行了测定和定值统计,其结果分别表示为:138Ce/142Ce=0.0225755±0.0000003,Ce=(117.4±1.3)μg/g,La=(55.8±0.9)μg/g。对二氧化铈化学试剂进行了溶液制备,以用于Ce同位素分析仪器标准物质。标准溶液编号为CBRICeO2,其138Ce/142Ce比值的测定统计值为0.0225748±0.0000006。为检验所制标准物质分析数据的准确度,对国际标样进行了比对测量,其中JMC304标准溶液的138Ce/142Ce比值测定结果为0.0225762±0.0000015,USGS玄武岩标样BCR-2的La和Ce元素含量测定结果分别为(25.2±0.6)μg/g(2σ)和(54.2±0.8)μg/g(2σ),所获数值与文献报道值或证书值在误差范围内相符。 相似文献
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Richard Giot Albert Giraud Francoise Homand 《Geotechnical and Geological Engineering》2006,24(4):919-947
This paper deals with a new strategy for initial stress identification by stress relaxation methods, coupled with finite element
calculation, and applied to the overcoring test. The back-analysis of such a test uses an inversion method which consists
in the minimisation, with a gradient-based algorithm, of a cost functional of least-squares type, which quantizes the difference
between measured and computed strains. The computed strains are assessed by three-dimensional finite element modellings of
the overcoring test. The inversion methodology is applied to a recent in situ overcoring test performed at Mont Terri laboratory, Switzerland. The inversion gave good results and allows us to validate
the inversion methodology. The constitutive law considered for this application is transverse isotropic elasticity but the
inversion method developed is applicable to most constitutive laws and every kind of in situ test. 相似文献
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现场X射线荧光光谱(XRF)测量因样品的不平度效应、不均匀效应和湿度效应等面临的技术难题,使得手持式XRF现场原位分析结果与实验室分析结果存在一定偏差。本文现场手持式X射线荧光光谱分析仪的测试时间、样品含量、测试距离、样品干湿度和样品粒度等测试条件对测试结果的影响进行了定量研究。结果表明:在最佳测试时间90s条件下,得到Cu、Mo、Pb、Zn元素测定限分别为57μg/g、14μg/g、24μg/g、38μg/g并给出测定限计算公式;现场分析测试距离应小于5 mm并保持样品表面干燥,块状样品测试方法最简单但测试结果变化最大,样品粉碎至粒径80目以上测试结果精准度最好,但制样过程较复杂,样品粉碎后的混合状态是现场测试的最佳策略。对西藏驱龙斑岩铜矿岩心扫描的实际应用表明,手持式XRF分析仪适合于现场原位分析,可满足野外斑岩铜矿圈定矿体等快速勘查评价要求,提高了工作效率并降低勘查成本。 相似文献
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电感耦合等离子体原子发射光谱法测定锑矿选冶中砷锑 总被引:1,自引:0,他引:1
采用电感耦合等离子体发射光谱法测定锑矿选冶过程中精矿、中矿、尾矿样品中的砷和锑元素。对矿样溶解、测定条件、介质酸度和基体干扰进行了实验,选用王水溶解矿样,在20%盐酸介质中测定,具有快捷、简便、测定范围宽等特点。砷和锑的质量浓度在0~20μg/mL范围内相关系数分别为0.9993和0.9998.对11份空白溶液进行测定,得到的砷和锑检出限分别为0.051μg/mL和0.080μg/mL;对GBW07174和GBW07175锑矿标样进行7次测定,相对标准偏差为1.26%~2.47%之间。 相似文献
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A. G. S. Cuthbertson K. Mills T. Wonter-Smith L. F. Blackburn J. J. Mathers P. Northing 《International Journal of Environmental Science and Technology》2013,10(5):1057-1066
The majority of recent quarantine schedules have relied on methyl bromide fumigation. However, due to the phase-out of this fumigant in January 2005 alternative treatments are needed. Four alternative chemical fumigants were tested for their potential to replace methyl bromide as a control agent for Bemisia tabaci, Liriomyza huidobrensis and Frankliniella occidentalis. Phosphine at 2 g/m3 gave promising results at 15 °C with complete mortality of all insects after 24 h exposure. Sulphuryl fluoride, ethyl formate and acetaldehyde caused severe damage to plant foliage after only 4 h exposure. However, sulphuryl fluoride produced 100 % mortality of L. huidobrensis pupae after only 2 h exposure. In a large scale test using phosphine 2 g/m3 at 15 °C complete mortality of L. huidobrensis eggs and pupae was recorded after a 24 h exposure. However, only 98.5 and 86 % mortality of B. tabaci eggs and F. occidentalis eggs, respectively, was recorded after this treatment. Treatments with phosphine produced no significant detrimental effects on subsequent plant growth. The potential of these chemicals to act as alternatives to methyl bromide as quarantine fumigants is discussed. 相似文献