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1.
王松  王军  任同祥  张继龙  周原晶 《质谱学报》2020,(1):19-27,I0001
浓缩同位素是校正质谱法、同位素稀释质谱法和双稀释剂法等同位素质谱分析技术的基础,其化学纯度及丰度量值的准确性直接影响着分析结果的准确性。但由于浓缩同位素中低丰度同位素的离子信号较难准确测量,且缺乏合适的标准物质校正,给高精准的同位素丰度分析带来挑战。本文建立了适用于微量铕浓缩同位素样品纯化的锌还原-萃取色层法,纯化后的151 Eu和153 Eu两种浓缩同位素纯度优于99.99%,有效消除了其他稀土元素杂质的干扰。通过采用1012Ω信号放大器的法拉第杯接收样品中的低丰度同位素离子信号,建立了铕浓缩同位素的全蒸发-热电离分析方法。两种浓缩同位素样品的主丰度测量结果分别为151 Eu 0.9683676(11)和153 Eu 0.9876851(21),测量重复性比1011Ω信号放大器的法拉第杯以及文献中校正质谱法的测量结果提高了3倍。  相似文献   

2.
文肠 同位素质谱用热表面电离质谱法测量高电离电位元素锑同位素丰度同位素稀释质谱法测定反应堆辐照元件样品中”Sm和’sosm含量Lead IsotoPe Analysis by Mass SPee-trometry and Its Applieation in Ar-ehaeometry避开衫干扰的钱同位素质谱分析石油稳定同位素地球化学新进展IDMS分析中化学处理特点及空白消除方法同位素稀释质谱(I DMS)文献介绍(1989ee1991)1.同位素稀释质谱(IDMS)文献介绍(1989~1991)1. 无机质谱离子注入样品的二次离子质谱(S IMS)定量分析粉末样品中某些杂质元素的同位素稀释二次离子质谱定量分析方法的研究…  相似文献   

3.
从理论上研究了热电离质谱计法拉第杯接收器放大器的非线性效应,建立了校正的数学模型。应用该模型,可以用一种同位素标准物质直接检验法拉第接收器放大器的非线性,而不用常规的系列同位素标准物质来检验放大器非线性。应用UTB-500铀同位素标准物质、峰跳扫描质谱测量技术,检验了一台热电离质谱计法拉第接收器放大器的非线性,并对存在的非线性进行了校正。同时,验证了在同位素丰度比值一定的情况下,非线性校正因子是恒定的,它不随离子流信号强度的变化而变化。  相似文献   

4.
采用热电离质谱法(thermal ionization mass spectrometry, TIMS)测定铀同位素过程中,质量分馏效应会引起同位素比值测量值偏离真值,一般采用外标校正法对质量分馏效应进行校正,这要求测量过程中标准物质和样品产生一致的质量分馏行为。因此,除考虑点样的一致性外,测量过程中产生单一的目标离子也非常重要。本研究采用热电离质谱技术考察了铼灯丝氧化对铀同位素测定的影响。将1 μg铀以硝酸盐溶液的形式点于铼样品带上,通过监测铀及其氧化物的离子流强度,发现铀主要存在U+和UOx+(x=1或2)的电离形态,并且灯丝表面氧化程度越高,UOx+的产率越高(UOx+/U+可达到1)。实验结果表明,灯丝去气过程过早使灯丝暴露于大气或点样过程中,以及使用较高的样品蒸干电流都会加剧灯丝的氧化。控制灯丝表面氧化或点样过程中加入石墨,可有效降低UOx+的产率,提高目标离子的电离效率。全蒸发测量结果表明,UOx+离子流强度大小对测量结果无明显影响,但通过降低UOx+的离子流强度,可提高测量结果的重现性,进而提高测量过程中分馏行为的一致性。该研究可为提高铀同位素测定过程中样品的利用率提供理论依据。  相似文献   

5.
应用同位素稀释电感耦合等离子体质谱法 ( ID-ICP-MS)测定地质标样 ( GSD-4和 GSD-8)和高纯石英中的痕量硼。样品处理采用低温密封焖罐酸溶样技术 ,将样品与稀释剂充分混匀 ,硼损失较小。硼元素在碱性条件下主要以 B( OH) 4 -形式存在于溶液中 ,可被硼特效离子交换树脂所交换吸附 ,故能很好地与大部分基体元素分离 ,从而减少基体效应。测定结果表明 :该方法测定痕量硼具有较高的准确度和精密度 ,且方法的检出限低 ,可达 5 1 .7ng/g,是准确定量测定痕量硼的理想方法  相似文献   

6.
本文介绍一种用于精确测定锂同位素比的坩埚—热电离法(CTI)。应用这种方法,样品LiCl量0.1微克,灯丝温度1600℃,电离带温度变化±100℃,外精度可优于±0.2%。用二种含高丰度~6Li和~7Li的溶液混合制备了三种工作标样,仪器经其标定,标定系数的标准偏差为±0.08%。  相似文献   

7.
热电离同位素稀释质谱技术在痕量分析中的新进展   总被引:1,自引:0,他引:1  
本文介绍1973~1984年间IDMS在地质学、年代学、核科学、海洋地质、海洋化学、环境科学、无机生物化学、临床医学、标准材料分析、高纯试剂分析及冶金学等方面的应用情况,并介绍负离子热表面电离技术、树脂球技术和四极质谱热表面电离技术的发展和应用。  相似文献   

8.
赵墨田  王军 《质谱学报》2002,23(3):180-180
用已知化学纯度的 16 2 Dy、16 4Dy两种浓缩同位素通过化学计量 ,配制人工合成校准样品 ,测量质谱计系统误差校正系数 K,校正用该仪器测量的来自地球不同地域矿物和试剂样品镝 ( Dy)元素天然同位素丰度比 ,求出自然界 Dy同位素丰度的真值。用该真值和它的核素质量 ,计算 Dy原子量 1 62 .4 995 ( 1 7)。上述测量经 IUPAC国际原子量委员会 ( UPAC-CAWIA)评审确认推荐报告中提供的测量值为 Dy原子量新的国际标准值 ,测量方法评为最佳测量  相似文献   

9.
同位素稀释质谱法测量环境样品中的微量元素   总被引:3,自引:0,他引:3  
本文简单介绍了同位素稀释质谱法 (IDMS)的原理和特点。综述了同位素稀释法在环境样品分析中的应用。对样品化学前处理中不同消解方法及用ICP -IDMS和TI-IDMS方法测量进行了比较。最后对IDMS方法今后的发展方向做了展望。  相似文献   

10.
赵墨田  王军 《质谱学报》1999,20(1):37-43
用已知化学纯度的两种浓缩同位素通过化学计量,配制人工合成样品,用来测量质谱计系统误差校正系数,校正用该仪器测量的来自地球不同地域矿样和试剂样品中锑(Sb)、铕(Eu)、铈(Ce)、铒(Er)四种元素天然同位素丰度比,求出这些元素同位素丰度的真值。用该真值和已知的上述四元素核素质量,计算得原子量分别为121.7597(7)Sb、151.9644(9)Eu、140.1157(8)Ce、167.2591(9)Er  相似文献   

11.
The precise determination of methylmercury (MeHg) in fish tissues has been performed by species specific isotope dilution mass spectrometricanalysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS). A labelled MeHg standard (ERM AE670, a Hg 202 enriched methylmercury isotopic reference material) commercial isotope provided by IRMM (Geel, Belgium) was used for these determinations. The experiment procedure included spiking, extraction, and a simultaneous separation and detection procedure. The method gave yield to good precision (<2%). The accuracy of the method has been validated on the certified reference materials BCR 464 (5.50±0.17 mg/kg MeHg) for the tunafish. The result obtained was in good agreement with the certified reference value. And this method was used to do the international comparison CCQM P39.1.  相似文献   

12.
The precise determination of selenomethionine (SeMet) in wheat flour has been performed by species specific isotope dilution mass spectrometric analysis (IDMS) using an inductively coupled plasma mass spectrometer as detector after liquid chromatography (LC-ICP-MS). A labeled 76SeMet species-specific isotope enriched spike solution was used for these determinations. The experiment procedure included spiking, extraction, and a simultaneous separation and detection procedure. The method gave yield to good precision (<2%). The accuracy of the method has been validated on the certified reference materials. The result obtained was in good agreement with the certified reference value. And this method was used to do the international comparison CCQM-K60.  相似文献   

13.
There are several basic characteristics of mass spectrometry that are not always fully appreciated by the science community. These characteristics include the distinction between relative and absolute isotope abundances, and the influence of isotope fractionation on the accuracy of isotopic measurements. These characteristics can be illustrated in the field of nuclear physics with reference to the measurement of nuclear parameters, which involve the use of enriched isotopes, and to test models of s‐, r‐, and p‐process nucleosynthesis. The power of isotope‐dilution mass spectrometry (IDMS) to measure trace elements in primitive meteorites to produce accurate Solar System abundances has been essential to the development of nuclear astrophysics. The variety of mass spectrometric instrumentation used to measure the isotopic composition of elements has sometimes been accompanied by a lack of implementation of basic mass spectrometric protocols which are applicable to all instruments. These metrological protocols are especially important in atomic weight determinations, but must also be carefully observed in cases where the anomalies might be very small, such as in studies of the daughter products of extinct radionuclides to decipher events in the early history of the Solar System. There are occasions in which misleading conclusions have been drawn from isotopic data derived from mass spectrometers where such protocols have been ignored. It is important to choose the mass spectrometer instrument most appropriate to the proposed experiment. The importance of the integrative nature of mass spectrometric measurements has been demonstrated by experiments in which long, double beta decay and geochronological decay half‐lives have been measured as an alternative to costly radioactive‐counting experiments. This characteristic is also illustrated in the measurement of spontaneous fission yields, which have accumulated over long periods of time. Mass spectrometry is also a valuable tool in the determination of neutron capture cross‐section measurements and the application of such determinations in Planetary Science. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 29:845–859, 2010  相似文献   

14.
207Pb同位素稀释剂与样品混合,加入H2O2和HF对混合样品进行消解,采用同位素稀释质谱法对两种不同铅含量国际比对焊锡样品中的铅进行了测定。使用常规硝酸和盐酸消解Sn-Ag-Cu系焊锡时易生成氯化银和β-锡酸不溶物的H2O2-HF体系避免了此类问题,并加快了样品消解速度。研究了样品基体对208Pb/207Pb比值测定及最终结果的影响,在保证精密度的情况下,通过逐级稀释的方式可降低测定过程中大量锡基体的干扰。建立了Sn-Ag-Cu系焊锡中高、低含量铅的准确测定方法,并对测定结果的不确定度进行了评定。CCQM-P119和CCQM-K88“无铅焊锡”中铅的国际比对结果表明,同位素稀释质谱法与传统方法相比,准确度高、不确定度小,测定结果获得了很好的等效度,从而进一步验证了方法的准确性和可靠性。该方法同样适用于焊锡基体标准物质的定值。  相似文献   

15.
周涛  赵墨田  王军  逯海 《质谱学报》2006,27(Z1):5-6
This report summarizes the application and development of isotopic and inorganic mass spectrometries in chemical metrology. Isotopic and inorganic mass spectrometries play an important role in chemical metrology. They are applied in determination of chemical standard data, such as atomic weights and isotopic abundances, and preparation of isotopic certified reference materials and spikes. Absolute determination method of isotopic abundances and isotopic dilution mass spectrometry method have the metrological characteristic, which have being used in research of chemical metrology.  相似文献   

16.
赵墨田  王军 《质谱学报》2002,23(1):56-56
化学元素的原子量是自然界的基本常数。原子量的概念对化学及相关学科的发展,起着基础性的推进作用。化学学科发展的两个理程碑:原子-分子学说和元素周期率,都是以原子量为基础。因此,各国化学家都十分重视它的测量和修正工作。原子量的测量已有180年的历史,其方法由最初的化学法、相对质谱法发展到目前的绝对质谱法,几经改进,测量值的不确定度有了明显提高,同时原子量的测量也反映一个国家的科学技术水平。  相似文献   

17.
The contents of lead, iron, copper in red wine were determined by using ICP-MS, ICP-OES, and an authoritative measurement method-isotope dilution mass spectrometry (IDMS). The results indicated that it was not easy to achieve agreements with IDMS by using common methods. If using some methods, such as matrix mathing and adding standards to reduce the inference of matrix, the results could be better. So it is necessary to use similar certified reference material to calibrate the method and correct the results when the complex matrix samples were measured.  相似文献   

18.
The set of operations used to upgrade an MИ-1201 magnetic sector mass spectrometer is described. The upgrading consisted of automating the recording system, developing the software, and modifying the vacuum system. The modified instrument was tested by analyzing both CO2 samples with a natural isotopic composition of oxygen and water samples enriched with the 18O isotope. The reproducibility of results from measuring the 16O concentration was 0.005%. For water samples enriched with 18O, the experimental results correlate with the predetermined isotopic concentrations.__________Translated from Pribory i Tekhnika Eksperimenta, No. 3, 2005, pp. 55–61.Original Russian Text Copyright © 2005 by Ivanov, Moiseeva, Trofimov, Dryannov, Aleksei Sysoev, Aleksandr Sysoev.  相似文献   

19.
针对制造系统信息的种类和数量的急剧增加,造成决策人员对大量信息处理和及时做出决策的困难,提出一种面向制造系统的仪表板(dashboard)——制造系统信息化控制台系统,为上述问题的解决提供了支持工具.首先分析了制造系统信息化控制台的内涵,并提出系统的体系结构,在此基础上,分析了实现制造系统信息化平台的关键技术,为系统的实现提供了理论基础.  相似文献   

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