共查询到19条相似文献,搜索用时 109 毫秒
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介绍了ZnAl_(4-1)锌合金标准物质的制备技术和研制过程。并以大量数据表明所研制的ZnAl_(4-1)光谱和化学两种标准物质都具有良好的均匀性和稳定性、定值准确可靠、符合国家一级标准物质的技术要求,达到了美国NIST同类标准物质的先进水平。 相似文献
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《一级标准物质技术规范》和《军用标准物质管理办法》及其实施细则规定 ,标准物质特性量定值有以下三种方式 :( 1 )用高准确度的绝对或权威测量方法定值 ;( 2 )用两种以上不同原理的已知准确度的可靠方法定值 ;( 3)多个实验室合作定值。在我国标准物质研制的实际工作中 ,大多采用后两种方式相结合的办法对标准物质特性量进行定值 ,即在策划定值方案时 ,既考虑采用两种以上不同原理的已知准确度的可靠方法 ,又由多个实验室进行合作定值。当采用多种方法和 /或多个实验室对标准物质特性量定值时 ,对多组观测值的数理统计处理结果表明 ,其标准… 相似文献
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研制了两种0~100℃热分析标准物质,分别为金属镓和水杨酸苯酯标准物质。研制的标准物质具有良好的均匀性和稳定性,采用与NIST,LGC相应标准物质比较的方法定值。NIST为SRM 2234镓,其定值采用288.6~314.35 K范围内的绝热热量计测得温度及热量值;LGC用绝热法为水杨酸苯酯的熔化温度和熔化热定值,两种方法都可以直接溯源至SI单位。对定值结果的不确定度进行了分析和评定。镓和水杨酸苯酯标准物质的熔化温度分别为(29.77±0.20)℃(k=2),(41.81±0.34)℃(k=2);熔化热分别为(80.52±0.48)J/g(k=2),(88.94±0.62)J/g(k=2)。研制的两种标准物质满足国家标准物质的技术要求,申报已获批准。 相似文献
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对研制的铜单元素溶液标准物质的定值方法进行研究。对原子吸收分光光度法和电感耦合等离子体发射光谱法的准确度和精密度进行比较,确定采用原子吸收分光光度法定值。与一级标准物质比较定值,将质量浓度为1 000μg/mL的铜单元素标准物质稀释得到标准系列,用原子吸收分光光度法分析,绘制标准曲线,用外标法对制备的二级铜单元素溶液标准物质进行定值,定值结果为100.1 mg/L,定值结果的不确定度为1.2 mg/L(k=2)。该定值方法可用于单元素金属标准物质和混合金属标准物质的定值。 相似文献
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电感耦合等离子体质谱法对GSS系列土壤及沉积物标准物质中多种元素的定值 总被引:1,自引:0,他引:1
介绍对10种GSS系列土壤及沉积物标准物质中多种元素进行定值的方法和结果,采用模拟土壤元素天然组成比值的校正溶液,对元素间的基体干扰具有明显的抑制作用,利用115In-103Rh双内标元素校正系统,可有效地抑制分析信号的动态漂移,建立了电感耦合等离子体质谱法对土壤及沉积物标准的物质中多种元素定值的方法,用该方法对GSS-4,GSS-5,GSS-8及GSD-9共4种土壤标准物质进行测定,绝大部分元素的测定结果与标准值的相对误差小于10%,相对标准偏差小于10%,对GSS-10-GSS-16,AMS-1,BEM及DMS-1共10种土壤及沉积物待定值标准物质进行定值,绝大部分元素测定结果的相对标准偏差小于10%。 相似文献
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建立了小麦粉中细交链孢菌酮酸(TeA)和腾毒素(TEN)标准物质的研制和定值方法,为开展粮食中交链孢霉毒素基体标准物质的研制提供重要方法学借鉴。该标准物质样品为天然污染交链孢霉毒素的小麦籽粒,定值目标物为TeA和TEN,采用同位素稀释-液相色谱-串联质谱法(ID-LC-MS/MS)进行定值测量,多个实验室合作定值。所研制的标准物质具有常温避光保存、定值不确定度小等特点。该标准物质是目前国际上唯一一种天然污染TeA和TEN的小麦粉标准物质,可用于食品安全风险监测、产品质量检测等领域相关分析方法的评价和测量质量控制等。 相似文献
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V. Balaram 《Accreditation and quality assurance》2000,5(8):325-330
Under an international collaborative certification programme, two new Polish soil reference materials, PL-1 (loess) and BPGM-1
(sandy loam soil), were analysed for 34 trace elements including all the rare earth elements using the acid decomposition
method and inductively coupled plasma - mass spectrometry (ICP-MS). After the certification by the organisers, the analytical
data obtained at our institute were compared with the certified data. 'Z-score' values calculated for individual trace elements
helped in the assessment of the quality of the data. While the majority of the data obtained on ICP-MS was very precise and
accurate, some of the data especially for elements such as Zr, Hf and Nb suffered from incomplete dissolution of the sample
and spectroscopic interferences. For some trace elements, certified data are not available for comparison. These features
together with the usefulness of interlaboratory collaborative programmes and ICP-MS for the certification of soil reference
materials are discussed.
Received: 6 August 1999 / Accepted: 28 February 2000 相似文献
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L. Hinojosa Reyes 《Analytica chimica acta》2009,631(2):121-476
A rapid and efficient closed vessel microwave-assisted extraction (MAE) method based on acidic leaching was developed and optimized for the extraction of total mercury (Hg), inorganic mercury (Hg2+) and methylmercury (CH3Hg+) from fish tissues. The quantitative extraction of total Hg and mercury species from biological samples was achieved by using 5 mol L−1 HCl and 0.25 mol L−1 NaCl during 10 min at 60 °C. Total Hg content was determined using inductively coupled plasma mass spectrometry (ICP-MS). Mercury species were measured by liquid chromatography hyphenated with inductively coupled plasma mass spectrometry (LC-ICP-MS). The method was validated using biological certified reference materials ERM-CE464, DOLT-3, and NIST SRM-1946. The analytical results were in good agreement with the certified reference values of total Hg and CH3Hg+ at a 95% confidence level. Further, accuracy validation using speciated isotope-dilution mass spectrometry (SIDMS, as described in the EPA Method 6800) was carried out. SIDMS was also applied to study and correct for unwanted species transformation reactions during and/or after sample preparation steps. For the studied reference materials, no statistically significant transformation between mercury species was observed during the extraction and determination procedures. The proposed method was successfully applied to fish tissues with good agreement between SIDMS results and external calibration (EC) results. Interspecies transformations in fish tissues were slightly higher than certified reference materials due to differences in matrix composition. Depending on the type of fish tissue, up to 10.24% of Hg2+ was methylated and up to 1.75% of CH3Hg+ was demethylated to Hg2+. 相似文献
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Determination of the minimum sample mass of a solid CRM to be used in chemical analysis 总被引:2,自引:0,他引:2
Summary A method for the quantitative determination of the minimum representative sample mass of a solid reference material is described and illustrated. If CRMs are to be used to calibrate microtechniques, the uncertainty which should be assigned to the certified value in that case, can also be evaluated. The method is applied in the preparation and certification of several reference materials with which CBNM was involved. 相似文献
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Liuxing Feng Liandi Ma Jun Wang Hai Lu 《Analytical and bioanalytical chemistry》2010,396(8):3051-3057
Two reference materials, at relatively low and high concentrations (GBW08404 and GBW08405), for analysis of the mass fractions
of Cd, Cr, Hg and Pb in polypropylene were developed. The reference materials were prepared by doping blank polypropylene
base material with Cd, Cr, Hg and Pb in the form of oxides, salts or pigments. Homogeneity and stability studies were performed
by inductively coupled plasma mass spectrometry. The certification of the four analytes was carried out by isotope-dilution
mass spectrometry (IDMS) with microwave-assisted digestion. Combined uncertainties were calculated from the IDMS uncertainty
evaluation budget and the uncertainty of the homogeneity. The mass fractions of Cd, Cr, Hg and Pb of the two certified reference
materials (CRMs) were from 8 to 1,000 mg kg−1. The two samples were also used in an interlaboratory comparison scheme in which National Institute of Metrology, China,
National Metrological Institute of Japan and Korea Research Institute of Standards and Science participated. The agreement
of the comparison results proved that the certification procedure of the CRMs is valid and that the certified values of Cd,
Cr, Hg and Pb are accurate and reliable. 相似文献