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1.
采用X射线荧光光谱法测定白云石中钠、镁、铝、硅、磷、硫、钾、钙、锰、铁、钛、锌等12种元素的含量。样品以四硼酸锂和偏硼酸锂为熔剂和溴化锂为脱模剂于1 050℃熔融,样片用于X射线荧光光谱分析。以GBW 07114、GBW 07216A、GBW 07217A、YSBC 11703-1995、YSBC28722-1993、YSBC 28723-1993等标准物质为基础制作工作曲线。优化了各元素的基体校正数学模型。对白云石样品重复测定11次,测得其相对标准偏差(n=11)在0.2%~7.3%之间。方法用于白云石标准样品的分析,所得结果与认定值相符。 相似文献
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应用X射线荧光光谱法测定了锌精矿中主次量组分(包括锌、硫、铁、硅、铅、铜、砷、银、镉、锡及锑)。锌精矿样品(0.6g)与6.3g四硼酸锂和3.2g硝酸锂置于铂-金坩埚中拌匀,先在500℃随即升至700℃灼烧10min,使样品中的硫离子预氧化为硫酸盐。硝酸锂与四硼酸锂生成四硼酸锂和偏硼酸锂混合物熔剂,在1 030℃熔融样品10min,将熔化的样品倒入样模中,冷却后脱模所得熔块用于X射线荧光光谱分析。对在预氧化及熔融过程中由于样品组成变化及质量的增加所造成的基体干扰,采用基于Sherman方程的可变理论α影响系数法进行校正。在所测定的元素中,锌和硫的校准曲线范围依次为27%~62%和10%~35%,两者的标准偏差均小于0.2%。应用所提出的方法分析了2个CRM(GBW 07168和SRM 113b),所得测定值与认定值一致。 相似文献
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应用熔融制样-X射线荧光光谱法测定了直接还原铁中主次元素的含量。样品置于铂金坩埚中,以四硼酸锂和偏硼酸锂为熔剂于1 050℃熔融20min,将熔化的样品倒入铂金模具中,所制得的片样用于X射线荧光光谱分析。以铁矿石标准物质GBW 07221等25种标准物质制作校准曲线,以固定理论α影响系数法校正基体效应。方法用于实际样品的分析,所得结果与其他方法测定值相符。测定值的相对标准偏差(n=10)在0.31%~16%之间。 相似文献
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采用X射线荧光光谱法测定钒钛磁铁矿中铁、钛、硅、铝、锰、钒、钙、镁等8种主次量元素。样品以四硼酸锂、偏硼酸锂和氟化锂(质量比为4.5比1比0.4)为熔剂,脱模所得熔块用于X射线荧光光谱分析。以GBW 07224、GBW 07225、GBW 07227、YSBC 19701-76、GSB 03-2584-2010、YSBC 19722-2011等6种标准物质和光谱纯二氧化硅、氧化钙、氧化铝、五氧化二钒、二氧化钛为基础制作校准曲线。优化了各元素的基体校正数学模型。各元素的检出限在3.79~39.06mg·kg-1之间。对钒钛磁铁矿标准样品GBW 07225重复测定10次,测得其相对标准偏差(n=10)在0.83%~2.9%之间。方法用于钒钛磁铁矿标准样品GBW 07225,GBW 07227的分析,所得结果与认定值相符。 相似文献
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采用熔融制样-X射线荧光光谱法测定铁矿石中钾、铅、锌和砷的含量。样品以四硼酸锂和碳酸锂为熔剂,在1 050℃下熔融20min,冷却后制成玻璃融片,用于X射线荧光光谱分析,以标准物质制作校准曲线。方法应用于铁矿石标准样品(GSB 1805-2005)的测定,测定值与认定值相符,测定值的相对标准偏差(n=10)在2.0%~4.5%之间。 相似文献
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用熔融制样法将钒铁合金样品在铂金坩埚中与四硼酸锂和偏硼酸锂熔融,熔体在铂金坩埚中自动成型,用X射线荧光光谱法测定钒铁合金中钒、硅、锰、铝和磷等主次元素含量。经试验求得熔融时,四硼酸锂、混合溶剂(四硼酸锂∶偏硼酸锂=67∶33)和样品的最佳质量比为30比5比1。各元素的检出限在12.4~51.2μg.g-1之间。方法用于标准样品分析,测定值与认定值相符。 相似文献
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应用X射线荧光光谱法测定了锰矿中主元素锰、铁、硅、钙和微量元素镁、铝、磷、硫、钛、钾、钠等11种元素.试样用四硼酸锂和碳酸锂混合熔剂融熔制成玻璃状熔片并加入碘化铵溶液作为脱模剂.以17个标准样品并结合6个自制标准样品建立校准工作曲线,用理论a系数校正基体效应.对该方法的精密度进行了考核,结果表明以上11种元素测定结果的相对标准偏差均小于4%.用3种标准样品对该方法的准确度进行验证,测定值与标准值相吻合. 相似文献
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《理化检验(化学分册)》2015,(8)
采用熔融制样-X射线荧光光谱法测定锰铁中硅、锰、磷、铬、镍和铜的含量。样品以四硼酸锂为熔剂,在300℃下加热15min,慢速升温至1 100℃,熔融15min,冷却后制成玻璃片,用于X射线荧光光谱分析。6种元素在一定的质量分数范围内与其信号强度呈线性关系,方法的检出限在15~59μg·g-1之间。方法用于锰铁样品的分析,测定值的相对标准偏差(n=11)在0.16%~3.6%之间。 相似文献
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X射线荧光光谱法测定高铬型钒渣中主次组分 总被引:1,自引:0,他引:1
杨洪春 《理化检验(化学分册)》2018,(6)
称取于750~800℃灼烧2h后的试样0.300 0g,置于盛有4.000 0g四硼酸锂、3.000 0g偏硼酸锂、0.500 0g碳酸锂的铂黄坩埚中,搅匀,加入300g·L-1溴化锂溶液0.5mL,在(1 050±20)℃熔融制片,采用X射线荧光光谱法测定高铬型钒渣中主次组分含量。采用钒渣标准样品和由标准样品加基准物质配制成的系列校准样品绘制校准曲线以消除基体效应,选择分析谱线并进行谱线重叠干扰校正。各组分的质量分数在一定范围内与荧光强度呈线性关系。方法用于分析高铬型钒渣样品,所得结果与滴定法、电感耦合等离子体原子发射光谱法的结果一致,测定值的相对标准偏差(n=10)在0.030%~7.3%之间。 相似文献
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《理化检验(化学分册)》2010,(8)
用熔融制样法将样品在铂金坩埚中与四硼酸锂熔融,熔体倒入铂金专用模具中成型为玻璃态块样。用X射线荧光光谱法测定锰锌铁氧体样品中氧化铁、四氧化三锰及氧化锌含量。经试验求得熔融时样品和无水四硼酸锂熔剂的最佳质量比为1比17.5。采用基体参数法和理论α系数法对基体效应及谱线重叠的干扰予以校正。此法用于锰锌铁氧体材料分析,3种组分的日间和日内相对标准偏差(n=7)分别小于3.5%和4.0%;用于标准样品的分析,3种组分的测定值与标准值之间的绝对误差在-0.15%~0.02%之间。 相似文献
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E. F. Dankova V. A. Bakulev Yu. Yu. Morzherin 《Chemistry of Heterocyclic Compounds》1992,28(8):931-936
The reaction of malonothioamides with benzene-sulfonyl azide and 2-azido-3-ethylbenzthiazolium tetrafluoroborate gave amides of 2-diazothiomalonic acid, which underwent cyclization to a mixture of 5-N-R-amino-1,2,3-thiadiazole-4-carbothioamides and 5-amino-1,2,3-thiadiazole-4-N-R-carbothioamides. The ratio of the isomeric thiadiazoles formed in this reaction is the same as in the reactions of 2-diazo-2-cyanoacetamides, 5-amino-1,2,3-thiadiazole- and 5-mercapto-1,2,3-triazole-4-carboxamides with P4S10 and of 5-amino-1, 2,3-thiadiazole-4-carbonitriles with H2S; it is characteristic of the influence of substituents on the reactivity of -diazothioacetamides. It was found that the cyclization of the diazo compounds is accelerated when electron-acceptor substituents are attached to the nitrogen atom of the carbothioamide group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1106–1112, August, 1992. 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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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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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》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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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