共查询到20条相似文献,搜索用时 93 毫秒
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采用Excel VBA开发了化学分析不确定度评定系统。借助Excel的内置函数和公式编辑功能,该系统可根据化学分析领域中不同的数学模型选择合成方法计算合成不确定度和扩展不确定度,同时获得反映各不确定度分量大小的直方图,提高了不确定度的评定效率。通过本系统获得的测量不确定度数据与文献相一致。 相似文献
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为建立并运用火焰原子吸收光谱法测定生活饮用水中锰的不确定度评定方法,根据《不确定度评定与表示》,并参考《化学分析测量不确定度的评定指南》,对火焰原子吸收法测定生活饮用水中锰进行了不确定度的分析和评价。结果表明,合成不确定度0.006 7 mg/L,扩展不确定度0.013 mg/L。运用该不确定度评定分析方法对测量过程中的关键环节进行重点质量控制,可有效降低引入的不确定度,保证测定结果准确。 相似文献
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分析测试不确定度的评定与表示(Ⅰ) 总被引:14,自引:0,他引:14
就“不确定度”概念的来历和意义;基本术语;误差与不确定度;化学分析测量不确定度的来源;不确定度的评定;标准物质的不确定度;不确定度的评定实例等7个方面概述分析测试不确定度的评定与表示,介绍不确定度的基本知识与应用。 相似文献
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分析测试不确定度的评定与表示(Ⅱ) 总被引:6,自引:0,他引:6
就“不确定度”概念的来历和意义;基本术语;误差与不确定度;化学分析测量不确定度的来源;不确定度的评定;标准物质的不确定度;不确定度的评定实例等7个方面概述分析测试不确定度的评定与表示,介绍不确定度的基本知识与应用。 相似文献
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张辰凌刘佳韩梅贾娜刘冰冰张永涛 《化学分析计量》2023,(1):88-91
建立电感耦合等离子体光谱法测定土壤中镍含量的不确定度评定方法。根据JJF 1135—2005《化学分析测量不确定度评定》和JJF 1059.1—2012《测量不确定度评定与表示》中的有关规定,分析了不确定度的来源,量化了各不确定度分量,计算得到了合成不确定度和扩展不确定度。采用置信概率为95%,包含因子k=2,电感耦合等离子体光谱法测定土壤样品中镍的质量分数测定结果为(35.3±1.2) mg/kg。影响结果不确定度的主要因素为校准曲线拟合、标准溶液配制、样品处理及测量重复性等。 相似文献
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评定燃烧氧化-非分散红外吸收法测定水中总有机碳的测量不确定度。根据JJF1059.1—2012《测量不确定度评定与表示》、CNAS-GL006—2019《化学分析中不确定度的评估指南》,该测量方法的不确定度来源主要有标准物质、溶液配制、校准曲线拟合、测量重复性。对各不确定度分量进行评定,最终合成得到测量结果的相对标准不确定度为1.34%,水样总有机碳质量浓度测定结果表示为(48.28±1.30)mg/L(k=2)。测量重复性是影响测量不确定度的主要因素,校准曲线拟合、标准物质的影响较小。 相似文献
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根据GB/T13748.21-2009镁及镁合金化学分析方法(光电直读发射光谱分析方法测定元素含量)对镁合金中锰元素含量进行了分析,对锰含量测量的不确定度来源进行了分析,并对测量过程中产生的不确定度进行了评定.此外,指出了该方法影响锰元素测量不确定度的主要原因,以期为镁合金中锰元素含量的光谱分析提供参考. 相似文献
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分光光度计测铁矿石中钛的测量不确定度评定 总被引:1,自引:0,他引:1
紫外-可见分光光度计在化学分析中应用较为广泛。对于借助其进行化学分析测量不确定度的评定,目前较多见于溶液测定。实际应用中,测试样品多为固体,涉及到称样、溶解、稀释、定容等步骤。此文试从随机效应和系统效应的角度考虑,对紫外-可见分光光度计应用ISO4691:1985铁矿石中钛含量的测定——二安替比林甲烷分光光度法对铁矿石中钛的测量过程中的不确定度来源进行了较为全面的分析,并最终给出评定结果。 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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Mustafa R. Ibrahim Zacharia A. Fataftah Paul von Ragu Schleyer Peter D. Stout 《Journal of computational chemistry》1987,8(8):1131-1138
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1988,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae. 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献