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针对石墨炉原子吸收法测定土壤中痕量金的测定过程,建立了数学模型,分析了其不确定度的来源,对不确定度的各分量进行量化,计算得出合成标准不确定度和扩展不确定度,并以不确定度的形式表达了测定结果。 相似文献
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通过笔者多年对原子吸收分光光度计仪器的使用,发现在测量金、银、铜、铅等多种元素时,其吸光度值在超过一定值后,吸光度和测量溶度就不完全符合A=KC。A=-lgI/I0=-lgT=KC是原子吸收仪器计算吸光度和溶度的基本公式,本实验就是研究在不同实验条件下得出不同的吸光度是否均符合此公式。 相似文献
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在计算电感耦合等离子体质谱法测定饮用水中锶的浓度(x)时,由于标准系列配制和仪器检测过程中信号(y)漂移产生的不确定度会传递给最终的计算结果。普通的一次或多次线性拟合结果不能真实地反映对于x、y值都含误差的数据拟合情况。文章对标准曲线进行了双误差回归计算,从双误差回归线性方程推导出校准曲线拟合过程产生不确定度的计算公式,建立了方法检出限与曲线拟合参数(x、y、曲线截距和斜率)及其相关不确定度之间的关系式,依据误差连续传递公式及不确定度分量计算公式简化了合成不确定度的表达式。从合成不确定度计算公式中可得出,水样中锶含量的浓度越低,其对应的不确定度越大;标准系列配制过程不细致、仪器灵敏度低,方法检出限越差,与实际测试情况符合。 相似文献
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根据测量不确定度的评定方法,对活性炭吸附-碘量法测定金矿石中的金进行不确定度评定。实验样品从低温升至650℃灼烧2 h除硫,用50%(体积分数)的王水溶解1 h,经活性炭动态吸附抽滤,将载金炭灰化复溶,用硫代硫酸钠标准溶液滴定,该方法简便、快速、实用性强。测量结果的不确定度由滴定样品消耗的硫代硫酸钠标准工作溶液体积、硫代硫酸钠对金的滴定度、称量质量、重复测定等不确定度分量组成。对各个不确定度分量进行分析并量化,合成得到测量结果的标准不确定度,换算成扩展不确定度。通过评定不确定度主要是由硫代硫酸钠对金的滴定度引入。 相似文献
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氢醌滴定法测定金矿石中金的不确定度评定 总被引：5，自引：4，他引：5
以氢醌滴定法测定金矿石中贵金属金的实例进行不确定度评定。测量结果的不确定度由配制金标准母液、金标准工作液、氢醌滴定液浓度、称样质量、滴定样品所用氢醌溶液体积等所引入的不确定度分量组成。在对各个不确定度分量进行量化的基础上，通过合成得到测量结果的标准不确定度，再乘以95％置信概率下的扩展因子2，得到测量结果的扩展不确定度。 相似文献
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化学测量中不确定度的计算方法——不确定度连续传递模型计算示例 总被引：2，自引：0，他引：2
不确定度连续传递模型的基本步骤为：①对标准曲线的各点进行不确定度评定,给出各点的标准不确定度;②对标准曲线各点的响应值进行多次测定,得出其平均值和标准不确定度;③以这2个标准不确定度为权重进行拟合,得出双误差拟合方程和标准不确定度的计算公式;④计算标准曲线各点与其校准点的差值,并将其转换成标准不确定度;⑤将以上4项按不确定度传播规律计算总不确定度。实际测量时, ①、②、④步用插值法算得。通过一个实例比较了不同拟合方法间结果的差别,说明了运用X、Y的相对误差作为权重的直线拟和,再加上“不确定度连续传递模型”算得的测量不确定度更为合理。 相似文献
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不确定度连续传递模型的基本步骤为：①对标准曲线的各点进行不确定度评定,给出各点的标准不确定度;②对标准曲线各点的响应值进行多次测定,得出其平均值和标准不确定度;③以这2个标准不确定度为权重进行拟合,得出双误差拟合方程和标准不确定度的计算公式;④计算标准曲线各点与其校准点的差值,并将其转换成标准不确定度;⑤将以上4项按不确定度传播规律计算总不确定度。实际测量时, ①、②、④步用插值法算得。通过一个实例比较了不同拟合方法间结果的差别,说明了运用X、Y的相对误差作为权重的直线拟和,再加上“不确定度连续传递模型”算得的测量不确定度更为合理。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.) 相似文献
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正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology, 相似文献
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正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.) 相似文献
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正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se- 相似文献
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正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with 相似文献