铂族元素地球化学标准物质的研制

ＧＰｔ＿１～７系列标准物质由土壤、水系沉积物、富镁超基性岩、富铁超基性岩、含铜镍贫铂矿石及铬铁矿等不同类型７个样品组成。铂族元素的含量范围从土壤和岩石的背景含量到矿石达４～５个数量级。经方差检验样品均匀度良好。标准物质的定值分析采用了不同类型的试金和湿化学法分离富集,以原子吸收、催化比色、催化极谱、等离子体质谱、发射光谱和中子活化等方法进行测定。定值的元素为Ｐｔ、Ｐｄ、Ｏｓ、Ｒｕ、Ｉｒ、Ｒｈ６个铂族元素及Ａｕ。该系列标准物质主要适于作铂族元素地球化学勘查和铂矿勘查中铂族元素分析的量值标准与测试的质量监控。     

Preparation and Certification of High-Grade Gold Ore Reference Materials (GAu 19-22)

Two types of gold deposit with both good homogeneity and a high-grade of gold were selected to prepare four gold ore reference materials (GAu-19,GAu-20,GAu-21 and GAu-22) by the Institute of Geophysical and Geochemical Exploration (IGGE),China.Seven laboratories participated in the certification programme. Volumetric methods for GAu19-21 and atomic absorption spectrometry for GAu-22 were used for the homogeneity testing,the coefficient of variation being found to be less than 3%.After sample digestion and preconcentration,the samples were analysed by flame atomic absorption spectrometry (AAS),colorimetry,neutron activation analysis (NAA)and volumetric analysis. The certified values for the gold concentration in GAu19-22 are 18.3 μg g -1, 32.3 μg g -1, 53.0 μg g -1 and 5.72 μg g -1,respectively.     

New Progress on Certified Reference Materials for Platinum-Group Elements: IGGE GPt-8, GPt-9 and GPt-10

Three new certified reference materials (CRM), certified for the platinum-group elements (PGE), GPt-8, GPt-9 and GPt-10 were developed based on the previous CRMs IGGE GPt-1 to GPt-7. The PGE concentration of GPt-8 is about 1 ng g^-1. GPt-9 and GPt-10 are ore samples with PGE concentrations of more than 1 μg g^-1. A multi-laboratory collaborative analysis scheme was adopted in the certification procedure, in which nine highly-experienced institutes and laboratories participated. The samples were analysed for the six platinum-group elements by nickel sulfide mini fire assay, with Te coprecipitation, and were determined by ICP-MS. Osmium was determined by isotope dilution.     

Gold and Platinum-Group Element Analysis of Geochemical and Platinum Reference Materials Using Fluoroxidation Decomposition

A novel method is described for the rapid dissolution of various geological, geochemical and related reference samples for the determination of Au and the platinum-group elements. The decomposition procedure is based on reaction with the fluoroxidants, liquid bromine trifluoride or molten potassium tetrafluorobromate. Results by this novel procedure are compared with data obtained by traditional methods of sample decomposition, including fire assay, autoclave techniques and an aqua regia leach. The oxidative fluorination procedure with the subsequent conversion of fluorocomplexes into the chloride form was found to be an effective and rapid method for the quantification of all the precious metals in a range of sample types.     

地球化学标准物质标准不确定度估算探讨

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。     

The Preparation and Characteristics of the Geochemical Certified Reference Material BEM (Emeishan Basalt)

A basaltic certified reference material BEM, prepared by Chengdu University of Technology, has recently been approved as a Primary Grade Reference Material (GBW07126) by the General Administration of Quality Supervision, Inspection and Quarantine of China. BEM was sampled from the Emeishan Basalts in China, which is one of the largest basalt provinces in the world. After successfully completing homogeneity and stability tests, collaborative analyses were carried out in seventeen Chinese institutes and laboratories and two American laboratories. More than ten reliable analytical methods based on different principles of measurement were adopted, of which ICP-MS, NAA and ICP-AES contributed 60.5% of all results. Fifty-four elements and oxide components were characterised as certified values, four elements as recommended values and nine elements as information values. A minimum sampling mass of 40 mg for most elements is recommended for use.     

Certified Reference Materials of Copper, Lead and Zinc (Silver) Ore Rocks and Their Concentrates (GSO 1-7)

Sulfide mineral certified reference materials GSO 1-7, recently prepared by the Institute of Geophysical and Geochemical Exploration (IGGE), were analysed by twelve laboratories. Various reliable analytical methods based on different principles were adopted and classical chemical methods were taken as the primary analytical methods, by which 5729 determinations were carried out, 1425 average data were obtained, and twenty one to twenty seven elements and components were certified.     

New Series of Rock and Sediment Geochemical Reference Materials

Certified or reference values for sixty six to sixty seven elements and element oxides are given for geochemical reference materials recently prepared by the Institute of Geophysical and Geochemical Exploration (IGGE), including limestone (GSR-13), granitic gneiss (GSR-14), amphibolite (GSR-15), lake sediment (GSS-9) and stream sediments (GSD-1a, GSD-13, GSD-14). These samples supplement the GSR 1-6, GSD1-8 and GSD 9-12 certified reference materials already prepared and characterized by the IGGE.     

泛滥平原沉积物标准物质研制

泛滥平原沉积物能代表流域内元素的平均分布规律并具有普遍的适用性,是地球化学填图工作的重要介质。目前国际上尚无泛滥平原沉积物标准物质,国外相似标准物质的研制注重于环境方面,定值成分较少;我国同类的土壤和水系沉积物标准物质受限于不同工作需要,研制目的各不相同,且多数标准物质不足。为满足需求,本文研制了长江流域、赣江流域、汉水流域、淮河流域、黄河流域、海河流域、黑龙江流域共7个泛滥平原沉积物国家一级标准物质(编号为GBW07385～GBW07391)。此系列标准物质采用X射线荧光光谱压片法测试了26种成分,主量成分的RSD小于1%,微量元素的RSD约为2%,所有成分的RSD均小于7%,方差检验的F值均小于临界值F0. 05(24,25)=1. 96,表明样品的均匀性良好。在23个月的考察期内,检验的24种成分未发现统计学意义的明显变化,证明样品的稳定性良好。由全国13家实验室采用不同原理的、可靠的多种分析方法共同完成了73种元素和化合物共511个特性成分的定值测试,除GBW07386和GBW07388的CO2未能赋值外,其余494个特性成分给出了认定值与不确定度,15个特性成分给出了参考值,是我国同类标准物质定值最为齐全的一个系列。该系列标准物质代表了各自流域元素的背景含量,适用于多目标地球化学调查、土地质量地球化学调查等样品的分析质量监控,亦可用作环境、农业等领域相关样品测试的量值和质量监控标准。     

国际标准物质数据库COMAR及有证标准物质

有证标准物质（CRMs）是具有准确量值的测量标准,在分析方法研究和评价、定性和定量分析、矿产勘查、仲裁检验、质量监督检验等领域发挥着重要的作用。20世纪80年代成立的国际标准物质数据库（COMAR）是目前国际上最大的CRMs数据库,收录来自25个成员国274个生产机构提供的CRMs数量超过10200种。本文从CRMs的数量、分类、发展变化等角度全面评述了国际数据库COMAR,阐述了欧盟组织、美国、中国、日本、澳大利亚等成员国的标准物质研究情况。英、美、法、德等国家的标准物质研究开展较早,研究水平高,处于世界领先地位;中国、日本等亚洲国家标准物质的发展虽起步晚,但发展迅速,已成为向COMAR提供CRMs最多的两个国家,分别为1194种和1456种（截至2013年8月）。COMAR建立以来,工业、有色金属和物理特性三大传统应用领域的CRMs占COMA数据库总CRMs的份额一直较大,比例始终保持50%以上,其中工业领域的CRMs数量最多,占19%;有机、生物与临床类CRMs所占份额最少,仅为7%和3%。随着社会需求的增加,生物与临床、生活质量领域标准物质成为未来标准物质发展的热点方向。本文指出,未来标准物质的发展将由过去的钢铁、有色金属、物理特性等传统领域逐渐转向食品安全、环境保护、气候变化、临床医学、制药产业、生物能源等新兴领域,标准物质的研究制备、定值及不确定度将面临新的技术挑战。     

中国地质标准物质文献索引(1980—2010)

汇集了自中国开展地质标准物质研制与应用工作以来发表的中外文献和专著221条,制成按年代编排的文献索引(1980—2010)、按专题(综合性评述、研制成果发表、制备技术与方法、专题评述和专著)编排的文献索引和作者索引。最后对文献的年度分布、各专题和各类(岩石、沉积物和土壤;矿石矿物;贵金属;能源矿产;化学物相;生物、食品材料;形态、有效态;同位素和年代学;电子探针微区)标准物质的文献分布及文献的期刊分布和作者单位分布等作了简单统计。     

Determination of Platinum-Group Elements and Forty Two Other Elements in Two Candidate Danish Cretaceous-Tertiary Boundary Clay Reference Materials by INAA, ENAA and RNAA

Ruthenium, rhodium, palladium, osmium, iridium and platinum (PGEs) and forty two other elements in two candidate geological Cretaceous-Tertiary boundary clay reference materials taken from the Fish Clay, Stevns Klint, Denmark, were determined by a combination of neutron activation analysis (NAA) consisting of instrumental, epithermal and radiochemical NAA with or without nickel sulfide fire assay preconcentration. The accuracy of the experimental values was assessed by the comparative analysis of the certified reference materials.     

黑色页岩样品中痕量级铂族元素地球化学成分标准物质研制

介绍了黑色页岩样品中6个铂族元素铂、钯、钌、锇、铑、铱的标准物质研制过程。黑色页岩样品采自贵州黄家湾,为一次采集、一次混样的原始样品,随机抽取包装好后的样品进行检验与定值。均匀性、稳定性符合要求后,按照国际标准化组织(ISO)34、35指南的基本要求和我国一级标准物质的技术规范,采用多个实验室协同测试的定值方式,利用不同原理的分析方法对此样品的6个铂族元素进行定值。以各实验室组数据作为最小统计单元,用Grubbs准则、Dixon法检验剔除离群数据,Shapiro-Wilk法检验各元素数据分布的正态性。检验结果100%的元素呈正态或近似正态分布。定值的6个元素均符合标准值水平。     

土壤界限含水率标准物质研制

界限含水率是细粒土定名分类、评价土的工程性质的重要依据,也是黏土矿勘查和工业利用的重要评价指标。不准确的界限含水率测试结果将可能导致严重的工程安全事故,造成人身和经济财产损失。标准物质是保障分析数据准确、可比和有效的重要手段,但当前国内外尚无土壤界限含水率标准物质,可见研制土壤界限含水率标准物质具有重要的现实意义。基于以上原因,本文严格按照《一级标准物质技术规范》(JJF 1006-1994)和《标准物质定值的通用原则及统计学原理》(JJF 1343-2012)等规范和标准,研制了5个土壤界限含水率标准物质(GBW07969、GBW07970、GBW07971、GBW07972、GBW07973)。候选物样品分别采自安徽淮北、山西大同及江苏南京等地,经人工粗碎、烘干、灭菌等加工处理后,采用大型球磨机将候选物样品细碎至粒径小于0.25mm。混匀、分装后每个候选物随机抽取25瓶进行均匀性检验,F实测值均小于临界值F0.05(24,25)=1.96,相对标准偏差(RSD)介于1.16%~2.67%之间,表明均匀性良好。12个月的考察期内进行的5次长期稳定性检验和考虑两种极端环境温度(60℃、-20℃)的短期稳定性检验,均未发现统计学意义的明显变化,候选物样品稳定性良好。经9家实验室采用2种经典土壤界限含水率测试方法联合定值,10mm液限、塑限和塑性指数3个定值指标的标准值分别介于26.3%~39.9%、16.3%~22.2%、10.0%~17.7%之间,梯度系列显著,涵盖了粉质黏土和黏土两种黏性土类别。该系列标准物质可用于仪器设备校准、质量监控、能力验证等技术质量活动,为水工环地质勘查、岩土工程勘察、黏土矿勘查等工作对土壤界限含水率测试数据准确性的要求提供了保障。     

钛铁矿化学成分标准物质研制

当前我国没有钛铁矿化学成分标准物质,只有与其相似的钒钛磁铁矿石标准物质,国外钛铁矿标准样品主要是钛铁矿精矿,不能有效地进行分析质量控制,因此迫切急需研制钛铁矿化学成分标准物质。本文研制了5个钛铁矿化学成分标准物质。样品采自山东省莒县棋山钛铁矿矿区、山东省沂水常庄钛铁矿矿区和河北省承德黑山钛铁矿矿区,采用流化床对撞式气流粉碎磨将样品细碎至粒度小于50μm,混合均匀后进行均匀性和稳定性检验,代表性元素的电感耦合等离子体发射光谱和电感耦合等离子体质谱分析结果表明方差检验的F值小于临界值,样品均匀性良好;所检验的元素经18个月6次分析,均未发现统计学意义的明显变化,样品的短期和长期稳定性良好;烘样温度(20~60℃)对亚铁(FeO)的稳定性并无影响,亚铁不会发生氧化。选择11家具有资质的实验室,采取经典分析方法与现代仪器分析技术相结合的方式,选用两种以上不同原理的准确度高的可靠方法对该标准物质联合定值,依照JJF 1343—2012和一级标准物质技术规范,5个钛铁矿化学成分标准物质给出了46项组分(包括主量、痕量和全部稀土元素)的认定值和不确定度,TiO2的含量范围为2.97%~19.76%,TFe的含量范围为18.88%~51.30%,基本涵盖了我国钛铁矿成矿类型,能够满足钛铁矿勘查、评价和开发的需求。     

金矿石化学物相分析标准物质的研制

介绍了金矿石化学物相分析标准物质的研制工艺及技术关键，列出了单体金、连生体金、硫化物包裹金、其他矿物包裹金及总金的原始数据和定值数据。经9个实验室共同分析协作，研制的5个标准物质已被国家质量监督检验检疫总局批准为国家一级标准物质。该系列标准物质主要用于金矿石化学物相分析质量监控、分析方法评价等。     

水系沉积物标准物质研制

为满足区域地球化学调查及矿产勘查的需要,新研制了15个水系沉积物标准物质,其中6个样品是原有水系沉积物标准物质的复制,9个新研制的样品主要采自中国北方的森林沼泽和干旱荒漠特殊景观区。样品粒度依据区域地球化学调查规范的要求,森林沼泽区采样粒级为2.0～0.22 mm,干旱荒漠区采样粒级为4.76～0.90 mm,山区和丘陵地区的采样粒级为小于0.22 mm。样品在室内晾干后在110℃烘24 h,置于大型高铝瓷球磨机粉碎并混匀,使样品中小于0.074 mm的部分大于99%以上。样品采用波长色散X射线荧光光谱进行进行均匀性检验,方差检验的F值小于临界值,所有元素的RSD均小于4%,大部分元素的RSD小于3%,P、Mn、Ti、Fe2O3、K2O等元素的RSD小于1%,证明样品均匀性良好。经2年内4次分析,检验结果表明对所检验的元素和成分均未发现统计学意义的明显变化,证明样品的稳定性良好。采用多家家实验室用不同原理的方法联合定值,邀请全国15家有资质的实验室采用准确度较高的方法分析测试约72种组分,根据ISO导则35和国家一级标准物质研制规范的要求,计算15种水系沉积物标准物质中72种元素和组分的标准值(部分组分给出参考值)和不确定度,这些新研制的标准物质是原有水系沉积物标准物质的一个补充。     

地质标准物质十年回顾

回顾了1992年以来国内外地质标准物质的主要情况。简单介绍了国际标准化组织在此期间颁布的有关文件。讨论了建立溯源性、均匀性检验等方面的一些问题。     

矽线石成分分析标准物质研制

随着矽线石应用领域的逐步拓展,英国、南非和日本等国家已研制了4种矽线石标准物质,而我国仅有一种矽线石国家二级标准物质,无论从组分的浓度梯度范围还是定值指标等方面,均难以满足我国研究需求。本文针对我国矽线石的分布情况,在黑龙江林口县和河南内乡县采集典型矽线石原矿2种,在黑龙江林口县采集矽线石精矿1种,按照国家一级标准物质研制标准和规范要求,研制了3种矽线石成分分析国家一级标准物质(批准编号为GBW07843、GBW07844、GBW07845)。均匀性检验结果表明,除个别指标(Y-1的TFe_2O_3、Cu和J-1的Mn O等)外,3种标准物质检测指标的F值均小于临界值F0.05(24,25)=1.96,组内和组间无明显差异;Y-1的TFe_2O_3、Cu和J-1的MnO等指标的组内和组间差异主要来源于分析方法误差,由此表明此批标准物质均匀性良好。在14个月考察期内,3种标准物质计算得到的拟合直线斜率b1均不显著,表明3种标准物质有较好的稳定性。经我国10家实验室使用多种分析方法对矿石中的主量元素、痕量元素和矽线石含量(硅铝,SAl_2O_3)等共计39种组分联合定值,各组分的相对扩展不确定度处于0.60%~29.9%区间,3种矽线石标准物质主量成分Al_2O_3的含量分别为25.85%、28.16%和55.06%。该系列矽线石标准物质可满足地质、环境等研究领域相关样品分析质量监控工作的需求。     

Determination of Gold, Silver and Platinum-Group Elements in Geochemical Reference Materials by Direct Atomic Emission Spectral Analysis Using a Multichannel Analyser Recording Device

A procedure for the analysis of geochemical samples has been developed based on direct atomic-emission spectrometry for the determination of silver, gold and the platinum-group elements. Instrumentation comprised a DC arc emission two-jet plasmatron coupled to a diffraction spectrograph and multichannel analyser for recording emission spectra. Spectrum analysis used a comprehensive library of spectral lines for practically all elements excited using this emission source. The software programme for the automatic registration of spectra and subsequent data processing are described and results presented for a number of geochemical reference materials.