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1.
分析了多目标生态地球化学土壤样品分析误差的主要来源,探讨了高精度测试分析方法的优化与选择,XFS法标准物质回归曲线对标准物质的含量与数量的要求;提出了质量监控粗大误差对F检验的影响,测量极大值和极小值的处理,内检样的合理插置,测试质量警告限的设置,组分总量的验证,异常抽查等一些实质性、操作性极强、具有实效的必要方法。 相似文献
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讨论了同位素地质样品分析的质量监控与质量评估问题,提出在同位素地质样品分析中以准确度与精度度并重、标准物质监控与重复样监控相结合的质量监控方法。通过对大量标准样品定值数据与积累的测试数据的统计分析,提出了标准物质测定误差和标准偏差及重复样双份分析的双差允许限的确定方法,并采用准确度分数、精密度分数、空白分数和系统性偏倚分数对测试结果的质量进行定量评估的方法,这些方法适用于实验室内部的质量监控和评估 相似文献
3.
地球化学标准物质标准不确定度估算探讨 总被引：4，自引：15，他引：4
在用高精度分析方法经检验证明样品均匀知识性和稳定性良好的条件下，可以以定值测试的不确定度表示标准物质标准值的不确定度。在较全面分析了地球化学标准物质定值测试的误差后，提出以测试结果平均值的标准偏差算得A类不确定度、以定值方法间的偏倚估计B类不确定度，以两者的合成值作为地理化学标准物质不确定度的估计值，并用其试算了部分已有地球化学标准物质有代表性元素的不确定度，结果表明提出的不确定度估算方法是可信的。 相似文献
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地质实验测试科技八五进展及九五发展计划设想 总被引：1，自引：0，他引：1
从岩矿测试、岩石矿物学研究、选冶技术、非金属矿开发利用、标准物质与标准方法、分析仪器的研制与技术改造等专业例举了代表性成果，对八五期间地质实验测试领域技术主要进展作了回顾；并依据地质矿业生产与发展的客观实陆，提出了九五期间地质实验测试技术发展计划设想，其重点是加强基础研究，发展高新技术、增强经济效益，促进地质科学研究和地质的矿取得重大突破以及地矿产业的迅速发展。 相似文献
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随着我国对生态文明建设的重视，自然资源综合调查势在必行，对生物标准物质亦提出了新的需求。当前相关调研工作已经大面积开展，自然资源综合调查、农产品与食品安全评价都需要对生物样品元素组成进行准确测试，需要以生物标准物质作为生物成分测试量值比对和溯源的基础，因此对生物基体标准物质的需求量大幅增加。大米作为主要粮食之一，其食品安全日益受到重视，对大米中的化学成分进行准确的分析测试具有重要的现实意义，因而对大米标准物质的需求量尤为突出，但目前大米成分分析标准物质已供不应求。本文严格按照《标准物质定值的通用原则及统计学原理》（JJF 1343—2012）和《地质分析标准物质的研制》（JJF 1646—2017）等相关规范要求，开展了GBW10010a大米成分分析标准物质的复（研）制工作，包括样品采集、加工制备、均匀性检验、稳定性检验、多家实验室协作定值测试及不确定度评定等关键环节。结果表明：本次复（研）制的大米标准物质定值成分多样、量值准确可靠，符合国家一级标准物质的要求。GBW10010a共定值54项主微量元素，包括Ag、Al、As、B、Ba、Be、Bi、Ca、Cd、Ce、Co、Cr、Cs、Cu、Dy、Er、Eu、Fe、Gd、Ge、Hg、Ho、K、La、Li、Ho、Mg、Mn、Mo、N、Na、Nb、Nd、Ni、P、Pb、Pr、Rb、S、Sb、Sc、Se、Si、Sm、Sr、Tb、Th、Tl、Tm、U、V、Y、Yb、Zn，其中的39项元素给出了标准值及不确定度，包括Ag、Al、As、B、Ba、Ca、Cd、Ce、Co、Cs、Cu、Dy、Er、Fe、Hg、K、Li、Mg、Mn、Mo、N、Na、Nd、Ni、P、Pb、Pr、Rb、S、Sb、Se、Si、Sm、Sr、Tb、Tl、Y、Yb、Zn；15项元素提供参考值，包括Be、Bi、Cr、Eu、Gd、Ge、Ho、Ho、La、Nb、Sc、Th、Tm、U、V。与原有GBW10010大米标准物质相比较，GBW10010a中As、Cd、Co、Cr、Cu、Hg、Mn、Mo、Ni、Zn等重金属元素含量显著下降，其中Cd、Cu、Zn降幅较大，分别下降约39%、43%、38.7%，一定程度上反映了农田生态环境的改善。本批标准物质定值元素总数量增加了6项，新增定值元素Ag、Nb（Nb给出参考值），并且各项元素不确定度范围整体上有所缩小，如Al、Cd、Cu、Fe、K、Mg、Mo、Na、P、Pb、Se、Zn等对生物易有影响的重要元素，表明了地质分析测试方法技术的进步及定值水平的提高。本批标准物质定值元素涵盖了具有生物效应的大部分主微量元素，适用于农业生态环境地球化学调查与评价、生物样品测试、农产品质量与食品安全评价样品测试时的分析仪器校正、分析方法评价和分析质量监控等多个领域。 相似文献
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西藏冈底斯山中段第四纪火山岩特征及地质意义 总被引：7，自引：1，他引：7
为辨别环境动态变化而进行的多期次环境地球化学填图要求降低不同期次数据间的分析误差，为达此目的，本文提出了衡量各实验室分析质量的新的考核标准，包括：一组标准样不同元素分析值与标准值对数偏差的不合格率；一组标准样不同元素分析值与标准值的相关系数所反映的相似性系数；一组标准样各种元素分析值与标准值在虚拟空间上图形分布的相似性。 相似文献
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中子活化分析大洋多金属结核标准物质的研究 总被引：2，自引：2，他引：2
采用中子活化分析相对＿Ｋ０法对研制的两个深海多金属结核标准物质ＧＳＰＮ＿２和ＧＳＰＮ＿３中的２６种主量和微量元素进行了定值测定，所得结果与初定值符合；对中子辐照自屏蔽效应进行了实验测定和理论计算，结果显示了很好的一致性；同时还对这两个多金属结核标准物中的Ａｓ、Ｂａ、Ｃｅ、Ｃｏ、Ｅｕ、Ｆｅ、Ｌａ、Ｌｕ、Ｍｎ、Ｍｏ、Ｎａ、Ｓｂ、Ｓｍ、Ｓｃ、Ｔｈ、Ｙｂ和Ｚｎ的取样量与取样误差关系进行了研究。结果表明，在ＧＳＰＮ＿２和ＧＳＰＮ＿３试样中分别有８种和１１种元素，在取样量１０ｍｇ时其取样误差小于１％。 相似文献
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Fe同位素的MC-ICP-MS测试方法 总被引：4，自引：0，他引：4
过渡族元素同位素研究是新兴的研究领域和国际研究前沿, 是同位素地球化学研究的热点。本研究利用Neptune型多接收等离子质谱(MC-ICP-MS), 采用标准-样品-标准交叉校正和以Cu为内标的方法对仪器的质量歧视进行校正, 对浓度效应、基质效应、干扰元素扣除和测试的长期重现性进行了检验, 建立了高精度的Fe同位素测试技术。这两种校正方法对实验室标准HSP I Fe在一段时间内δ56Fe和δ57Fe的测试结果分别为0.08‰(2SD)和0.14‰(2SD)分析精度达到国际同类实验室水平, 测试结果在误差范围内与文献值完全一致。 相似文献
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中国火成岩化学元素的丰度与分布 总被引：19，自引：3，他引：19
在中国各构造单元构选采了１０３６４件火成岩样品合成１１３１个分析样，采用仪器中子活化法，Ｘ射线荧光光谱法，原子吸收法，原子荧光光谱法，催化波极谱法和分光光度法等１５种可靠分析方法进行测试，对一些难测痕量元素采用了最新的分析研究成果，以同类国家一级标准物质监控分析质量。 相似文献
11.
Karen Hammes Ronald J. Smernik Jan O. Skjemstad Michael W.I. Schmidt 《Applied Geochemistry》2008,23(8):2113-2122
A recent comparative exercise found that different black carbon (BC) quantification methods produced widely varying results for a set of BC reference materials that included three laboratory-produced BC-rich materials, five environmental BC matrices and four samples of non-BC organic matter. This variation was attributed to a range of physical and chemical properties of the samples that could, in various ways, result in the over- or under-detection of BC in some or all of the techniques. Here the most pertinent chemical and physical characteristics of the samples are presented, including elemental analysis, lightness measurements, BET surface area measurements and 13C NMR analysis. Amongst the BC-rich materials, soot and char could be distinguished from one another mainly on the basis of H/C and O/C ratios, NMR observability and BET surface area. The results indicate that the aromatic structures in the soot are more highly condensed, and this explains why some BC quantification techniques detect these two materials differently. The non-BC potentially interfering materials were shown to share properties with the BC-rich materials (high C content, low lightness values and high aromaticity) that are used for certain BC quantification methods. This may lead to overestimation of BC unless these interfering materials are removed during pre-treatment. The environmental matrices were found to have relatively high amounts of metal oxides that have the potential to catalyse or inhibit thermal and chemical reactions during BC analysis. 相似文献
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使用粉末压片法制样,X射线荧光光谱法测定地质样品中氯,探讨了样片背衬、样片接受X光照射时间对测量结果的影响。Cl的精密度(RSD,n=12)小于10%。Cl的方法检出限为12μg/g,采用国家一级标准物质分析验证方法,其结果与标准值相符。 相似文献
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ICP-MS测定地质样品中37个元素的准确度和长期稳定性分析 总被引：8，自引：10，他引：8
对Elan6100DRC型ICP-MS近五年来所测得的国际地质标样BHVO-1(玄武岩)和AGV-1(安山岩)中的37个元素的测定值以及仪器灵敏度的长期漂移情况进行了统计分析(共计146次)。结果表明,几年来ICP-MS所测数据的长期稳定性和准确度都较好,除个别元素Li(BHVO-1)、Be(BHVO-1))、Cr(AGV-1)、Cs(BHVO-1)和Pb(BHVO-1)的相对误差(与参考值比较)接近或略大于10%外,绝大多数元素的相对误差和相对标准偏差(RSD,测定值之间,n=146)都在5%以内;仪器灵敏度并不是随着时间一直往下漂,有的是往上漂的,也有上下漂的,即使是在同一时间内,有的元素灵敏度往上漂,而有的往下漂。常用的内标法无法较好校正这种漂移,而需要采用内外标相结合的校正方法。不同批次,210个各种地质样品中Rb、Sr、Zr和Nb的XRF和ICP-MS分析结果对比情况表明,绝大多数样品中Rb、Sr、Zr和Nb的ICP-MS和XRF的测定值的相对误差小于10%。以上的分析结果表明,我们实验室所建立的以密闭高温高压消解技术为样品前处理方法,以模拟地壳样品中元素天然丰度比的基体匹配校正标准溶液为外标和以Rh为内标结合外标校正的ICP-MS多元素分析方法具有非常好的准确度和长期稳定性。 相似文献
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Christophe Cloquet Olivier Rouxel Jean Carignan Guy Libourel 《Geostandards and Geoanalytical Research》2005,29(1):95-106
In this study, the Cd isotopic composition of various geological reference materials and anthropogenic samples was investigated. The measurements were made by multicollector ICP-MS and instrumental mass fractionation was controlled using a "sample-standard bracketing" technique. Cadmium isotopic data are reported relative to an internal Cd solution (Cd Spex) and expressed as the 114 Cd/110 Cd delta value. Two other Cd solutions (Prolabo and JMC) were analysed and yielded the same 0% delta value. A fractionated Cd metal sample (Münster Cd) was used as a secondary reference material for Cd isotopic measurements and we obtained a 114 Cd/110 Cd delta value of 4.48% relative to Cd Spex solution. As opposed to multi-stage Cd purification previously published in the literature, a new one step anionic exchange purification using dilute HCl for the analysis of Cd isotopes in geological samples was developed. This method enabled a high recovery (> 95%) and effective separation of the sample matrix to be achieved. The long-term external reproducibility was evaluated at 0.12% (2 standard deviations) for the 114 Cd/110 Cd ratio, based on reference solutions and replicated measurements of samples over one year. The variation of Cd isotopic composition of natural terrestrial samples is restricted to a small range of 0.4%, which is similar to previously reported results. In contrast, large variations of Cd isotopic composition were found for anthropogenic samples with values as low as −0.64% for a dust sample issued from a lead smelter and values as high as +0.50% for NIST SRM 2711 (metal-rich soil). These variations are 10 times larger than the reproducibility and suggest that Cd isotopes can be useful as tracers of anthropogenic sources of Cd in the environment. 相似文献
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由于结构面粗糙度具有各质异性、各向异性、非均一性和尺寸效应等特征，结构面粗糙度系数（JRC）取值具有不确定性，工程中广泛采用统计方法来分析结构面粗糙度性质，然而以往研究往往忽略样本数不足对统计结果的影响。针对结构面粗糙度统计测量时无法确定合理样本数的问题，分别提出基于变异系数级比分析及简单随机抽样原理的最小样本数确定方法。以实际工程岩体结构面表面数据为研究对象，对比分析两种方法在系列尺寸下确定的统计测量最小样本数。实例分析表明：小尺寸样本的变异系数（CV）值明显大于大尺寸样本，且CV值随取样尺寸的增大而减小，取样尺寸为10～50 cm的CV值基本稳定在0.31～0.47之间，取样尺寸为60～100 cm的CV值基本稳定在0.21～0.31之间；最小样本数与取样尺寸基本满足幂函数关系，且最小样本数随取样尺寸的增大而减少；系列尺寸下级比分析方法在允许误差为±2%时确定的最小样本数与简单随机抽样原理在最大允许误差为10%、置信度为95%时计算的最小样本数是一致的，相似度大于0.997。该研究方法可为工程岩体中定量获取结构面粗糙度统计测量最小样本数提供依据，保证了JRC（结构面粗糙度系数）统计测量结果的准确性，对工程岩体稳定性评价中结构面力学参数的准确获取具有重要意义。 相似文献
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Takashi Sano Toshiaki Hasenaka Hiroyuki Sawahata Takaaki Fukuoka 《Geostandards and Geoanalytical Research》2006,30(1):31-37
Prompt gamma neutron activation analysis was applied to the determination of the titanium, potassium, samarium and gadolinium contents of nine Geological Survey of Japan (GSJ) reference materials (JB-1, 1a, 2, 3; JA-1, 2, 3; JR-1, 2). Firstly, the values in JB-1 were determined by the standard addition method: pressed powder disks of JB-1 were used for neutron irradiation and gamma-ray measurements, after known quantities of standard reagents had been added. Secondly, the contents of eight other reference materials were determined by comparison methods using JB-1 as the comparative standard. The precision of analyses were obtained by replicate determinations on these samples. The relative standard deviation was generally less than 5%. For most samples, analysed values agreed well (< 5%) with the recommended values. 相似文献
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INGRID U. OLSSON FRANCIS A. N. OSADEBE 《Boreas: An International Journal of Quaternary Research》1974,3(4):139-146
The formulas for correcting 14 C measurements are explained. The expected ranges of the δ13 C values for some types of samples are given. It is pointed out that the corrections are approximate because of the choice of correction formula, and that all samples arc normalized to wood samples instead of to carbon dioxide of the air. Some results from the Uppsala laboratory for plant materials and carbonates are given. 相似文献
19.
The results obtained from measurements of potassium ethyl xanthate (EtXK) sorption by synthetic chalcocite (Cu2S) and the results of chalcocite floatability measurements are presented.Five chalcocite samples, denoted as Cu2S A, B, C, D and E, were used for the measurements. Chalcocite samples of 60–75 μm were prepared in the same manner but were kept under conditions which differed in their degree to prevent surface oxidation by atmospheric oxygen.Chalcocite surface oxidation has a strong effect both on xanthate sorption and on chalcocite floatability. The maximal amount of xanthate abstracted (Qmax) by chalcocite samples from deoxygenated solutions after a long sorption period increases with increasing oxidation of the samples. The Qmax values give information concerning the total amount of surface oxidation products.Chalcocite decreases its floatability with increasing surface oxidation. Most oxidized chalcocite samples required an about 100 times greater collector consumption to obtain the same flotation results than the least-oxidized samples studied. 相似文献
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The effective porosity, saturated sonic velocity and saturated uniaxial compressive strength were determined on a large number of Borrowdale Volcanic Group volcaniclastic core samples from three boreholes at Sellafield, Cumbria. The work formed part of the UK Nirex Limited site investigation into whether the Sellafield area could be suitable as a repository for intermediate and low level radioactive waste. Most of the intact samples were of low to very low effective porosity, had a high sonic velocity and were very strong to extremely strong. However, a proportion of values deviated significantly from this. Bivariate analysis showed a negative relationship exists between sonic velocity and effective porosity. The cross plots of these two parameters with uniaxial compressive strength showed a wide range of strength values for samples of low effective porosity and high sonic velocity. Six failure types were identified during the uniaxial compressive strength tests. The strongest samples tended to fail through the matrix and the weakest rock samples tended to fail through haematized material or along haematized veins. Effective porosity and sonic velocity measurements could not distinguish between those samples that failed through the matrix and those that failed along discrete narrow veins. The presence of narrow haematized veins has a major effect on the intact rock strength. 相似文献