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61.
The preparation and characterisation of three nickel ores and two nickel concentrate certified reference materials are described in this paper. The samples of nickel ore and nickel concentrate were collected from the Hongqiling nickel deposit in Jilin province. The raw materials were crushed and passed through a 2.0‐mm sieve. The rough samples were then ground for 48 hr in a high‐alumina ball mill to a final size of < 0.074 mm. Homogeneity of the samples was tested by X‐ray fluorescence spectrometry (WD‐XRF) and inductively coupled plasma‐atomic emission spectrometry (ICP‐AES). The relative standard deviations (RSD) of results on mass fraction measurements by WD‐XRF were < 1.0% m/m for eighteen components. F‐tests showed that all five samples were homogeneous. Nineteen laboratories contributed with measurement results (2127 in total) for the certification of mass fractions for twenty‐three elements and compounds. Twenty‐three components in the nickel ores and twenty components in the nickel concentrates were characterised as certified values, while the Ni mass fractions ranges from 0.1 to 9.02% m/m in these certified reference materials. These five samples were approved as national certified reference materials by the National Organisation of Reference Materials of China in 2012.  相似文献   
62.
鹰扬关构造混杂岩出露于湘-粤-桂三省(区)交界处,构造上位于扬子陆块与华夏地块结合带西南段,在形成过程中保存了丰富的物质记录和构造演化信息,是研究扬子陆块与华夏地块拼合造山过程及相互关系的重要对象。对鹰扬关构造混杂岩物质组成及变形特征的详细研究表明,其由基质与岩块组成,基质为变质含凝灰质细碎屑岩,岩块为变质火山(碎屑)岩、微晶石英岩与大理岩等;根据野外变形特征及各期变形的叠加改造关系,于鹰扬关构造混杂岩中识别出5期构造变形,并建立了5期构造的相对变形序列。S1、S2代表晋宁期变形作用(D1~D2); S3及NNE向断层左行走滑运动指示加里东期NW-NNW向挤压作用(D3);印支期及早燕山期W-NWW向挤压作用(D4)对前期构造进行了改造, NNE向断层发生右行走滑运动;晚燕山期的伸展作用主要表现为正断层活动(D5)。变形序列的建立为区域构造过程的探讨和对比提供了新的基础资料。  相似文献   
63.
Here, we present determinations of thallium (Tl) concentrations in the USGS reference materials BIR‐1G, BHVO‐2G and BCR‐2G measured by solution ICP‐MS. The Tl content in these three glasses spans a range of about 2–230 ng g?1, which is similar to the values published for the respective powder materials. The determined range of Tl concentrations in these three glass reference materials makes them ideal for investigating Tl concentrations in basaltic and andesitic volcanic glasses. We also performed a series of laser ablation ICP‐MS measurements on the three samples, which show that this technique is able to determine Tl concentrations in glass samples with concentrations as low as 2 ng g?1.  相似文献   
64.
岩性—构造填图结果表明,大洪山区的原“花山群”实际上包含3套不同时代、不同环境的物质建造,应予以解体。其中襄广断裂带内分布的以基性火山岩为主的一套岩系是构造侵位的蛇绿混杂岩,称之为花山蛇绿混杂岩;大洪山以西的耿集—板桥火山—沉积岩系,是南秦岭随县群的构造岩块;剔除这两者之后的碎屑沉积岩系定为真正意义的花山群,沉积时代为晚元古代。  相似文献   
65.
This article presents new boron concentrations for nine geochemical reference materials (GS‐N, FK‐N, GL‐O, BX‐N, DT‐N, AN‐G, GH, Mica‐Fe, Mica‐Mg). After extraction by a modified pyrohydrolysis technique, boron concentrations were measured by ICP‐MS. The blank levels for the whole procedure were 0.091 ± 0.020 ng ml?1 or 14 ± 5 ng of boron in total. The method was first validated by measuring nine reference materials with known boron concentrations. The determined boron concentrations are all within the range of recommended or published values, which means that the yields were 100%, and show precisions below 10% for samples containing over 2 μg g?1 of boron.  相似文献   
66.
This article describes a series of methods developed for the determination of total carbon (CTotal), organic carbon (Corg), hydrogen, nitrogen and sulfur. The following elemental analysers were used: LECO model RC‐412 for the determination of organic carbon, total carbon and hydrogen; LECO model CS‐200 for the determination of total carbon and sulfur; LECO model TN‐400 for the determination of nitrogen; and LECO model TruSpec CHNS for the determination of organic carbon, total carbon, hydrogen, nitrogen and sulfur. Uncertainty and limits of detection and quantification were calculated for each method, as well as the running costs to define the most effective instrument for each material and each analyte. Accuracy was checked by the application of the Sutarno–Steger test. Finally, a compilation of the results obtained in the determination of CTotal, Corg, H, N and S in forty‐nine reference materials is presented.  相似文献   
67.
Round 23 of the GeoPT international proficiency testing scheme included the ferromanganese nodule powder FeMn‐1 which was distributed as an additional sample (23A). The aim of this initiative was to assess overall analytical performance for such a challenging oxide matrix with a view to the possible certification of such a material in accordance with ISO Guide requirements. To investigate inter‐method discrepancies, precision data and the method means for the most frequently used analytical methods (XRF, ICP‐MS and ICP‐AES) and sample preparation techniques were calculated and then compared using statistical tests of equivalence. For most major elements, XRF and ICP‐AES data dominated and these were found to give equivalent results. In contrast, for most trace elements significant discrepancies were detected between data obtained by different analytical methods. Possible causes are discussed with a view to attributing their origin to calibration strategy, sensitivity or interferences. It is assumed that the unusual oxide matrix generated unexpected interferences and thus method bias. Discrepancies observed between data from different analytical methods provide valuable information for the participating analysts, helping them to avoid systematic errors and thus minimising bias. They also suggest actions necessary to improve results for any future certification of such a material.  相似文献   
68.
采用构造岩相学和构造-古地理单元恢复、AMT、地面高精度磁法等综合方法,对甘肃红石山和邻区泥盆纪—石炭纪有限洋盆进行重建,对红石山蛇绿混杂岩带进行构造岩相学解剖和深部探测。划分出5个构造层,前华里西期、华里西期、印支期、燕山期和喜山期。北部构造带为四顶黑山-雀儿山晚古生代岩浆弧相,中部构造带红石山蛇绿混杂岩带恢复为泥盆纪—石炭纪有限洋盆相+洋壳残片相,南部构造带为白山-狼娃山晚古生代岛弧相。蛇绿岩套从下到上的垂向单元为晚泥盆世—早石炭世变质超镁铁杂岩→堆晶超镁铁-镁铁岩→均质辉长岩和少量的辉绿岩墙→早石炭世扫子山期深水相硅质岩和含炭硅质细碎屑岩(有限洋盆相)。陆缘海相岛弧地体南北两侧为早石炭世扫子山期和白山期浅海相火山岛弧带。哈萨克斯坦板块南缘南向俯冲碰撞在敦煌地块北缘增生楔构造背景下,形成SSZ型蛇绿岩套。红石山构造-蛇绿混杂岩带与周缘地质体具有不同的构造岩相学边界,从北向南具有明显的4个构造岩相学水平分带,中心部位为超基性岩构造岩块单元,以糜棱岩相辉长岩和蛇纹石片岩为包络面的构造岩片(基质单元),蛇绿混杂岩带总体为无根状大型透镜体。红石山构造-蛇绿混杂岩带将两侧地质体卷入混杂岩带内,这种复杂镶嵌结构的构造岩相体有利于形成大型-超大型斑岩型金铜钼矿床、浅成低温热液金矿床和造山型金矿床。  相似文献   
69.
We present new reference values for the NIST SRM 610–617 glasses following ISO guidelines and the International Association of Geoanalysts’ protocol. Uncertainties at the 95% confidence level (CL) have been determined for bulk‐ and micro‐analytical purposes. In contrast to former compilation procedures, this approach delivers data that consider present‐day requirements of data quality. New analytical data and the nearly complete data set of the GeoReM database were used for this study. Data quality was checked by the application of the Horwitz function and by a careful investigation of analytical procedures. We have determined quantitatively possible element inhomogeneities using different test portion masses of 1, 0.1 and 0.02 μg. Although avoiding the rim region of the glass wafers, we found moderate inhomogeneities of several chalcophile/siderophile elements and gross inhomogeneities of Ni, Se, Pd and Pt at small test portion masses. The extent of inhomogeneity was included in the determination of uncertainties. While the new reference values agree with the NIST certified values with the one exception of Mn in SRM 610, they typically differ by as much as 10% from the Pearce et al. (1997) values in current use. In a few cases (P, S, Cl, Ta, Re) the discrepancies are even higher.  相似文献   
70.
果芒错蛇绿混杂岩位于狮泉河—永珠—嘉黎蛇绿混杂岩带中段,是该带中保存较好的一套蛇绿混杂岩,其形成环境是确定狮泉河—永珠—嘉黎蛇绿混杂岩带构造属性的重要依据。对果芒错蛇绿混杂岩中的硅质岩进行了地球化学分析,为判断蛇绿混杂岩的形成环境提供新的约束条件。硅质岩通常呈几十厘米夹层产于玄武岩中,含有大量晚三叠世—白垩纪放射虫化石。硅质岩SiO2含量为71.38%~77.67%,Al2O3含量为8.62%~11.51%,MnO/TiO2值为0.28~0.35,(Ce/Ce*)SN值为0.92~0.94,(La/Ce)SN值为1.13~1.17,反映了陆源物质的影响,而V、Ni、Cu和V/Y值高于大陆边缘硅质岩,与洋中脊和大洋盆地硅质岩相似,说明果芒错硅质岩可能形成于受陆源物质影响且与大陆边缘有一定距离的环境中。结合变质橄榄岩、镁铁质岩墙和玄武岩的地球化学特征,初步认为果芒错蛇绿混杂岩的形成环境为靠近大陆边缘的弧后盆地。  相似文献   
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