罗布泊地貌地质遗迹中某些元素的分析

用中子活化分析法测试了新疆罗布泊地区地质样品中的某些痕量、微量及常量元素含量,特别是对样品中放射性元素作了检测。结果表明,该地区的地质遗迹样品中,痕量、微量及常量元素的含量与中国大陆地壳中的含量相当,无明显的放射性异常;把这些样品当作建筑材料的原材料来使用,是安全的;通过对这些样品的检测分析,为该地区的化探普查提供了可靠的依据。     

国际原子量表(1975)

相对原子质量标准刁,(c‘皿)一12 许多元素的原子盘并非固定不变,而是决定于材料的来源和处理的经历。表中的附注详细注解了各元素可能有的变化情况。本表提供的价(E)值应用于在地球上存在的天然元素和某些人工合成元素。应对附注给予应有的注意。各原子t数健最后一位数字准至土1,带星号.的准至土3。括弧中的数值用于某些放射性元素,它们的司确原r星因与来源有关而无法提供,表中数值是该元素已知半衰期最长的同位素的原子质量数。     

王水提取-电感耦合等离子体质谱法同时测定地质样品中微量银、镉、铋

样品用水浴加热、王水提取预处理,采用电感耦合等离子体质谱法同时测定了土壤、水系沉积物及岩石等地质样品中的痕量Ag、Cd和Bi。在样品预处理阶段,主要干扰元素Zr和Nb只有少量被溶出,而分析元素Ag、Cd和Bi的溶出趋于完全,这样在样品预处理阶段就完成了分析元素与干扰元素的有效分离,减小了多原子离子93Nb16O ,92Zr16OH ,92Mo16OH 对109Ag的干扰和95Mo16O ,94Zr16OH ,94Mo16OH 对111Cd的干扰。方法对实际样品的检出限(10σ,DF=300)Ag,Cd和Bi的质量分数分别为5.1,4.3和10.5ng/g。对不同含量样品7次测定的RSD为8.7%~1.8%。用该方法对土壤、水系沉积物及岩石等国家一级标准物质进行分析,分析数据均在标准推荐值的允许误差范围内。     

激光熔蚀微探针-电感耦合等离子体质谱法--一种快速测定岩石样品中多个元素的新方法

利用激光探针与等离子体质谱联机技术(LAM-ICPMS)同时测定岩石样品中35个元素.对岩石标样的碱熔玻璃进行了系统的LAM-ICPMS方法研究.结果表明,采用散焦(defocus)激光束扫描法获得了连续稳定的分析信号,并提高了分析灵敏度和分析精密度.该法测定P的检出限为0.1%,Sc、Ti、V、Cr、Mn、Co及Ni的检出限为1.6×10-6～12×10-6,Ga、Rb、Sr及Ba的检出限为0.2×10-6～0.6×10-6,其余21个微量元素的检出限为10-9级;内部精度优于15%,外部精度优于10%.3个岩石标样(NTUG-1、NTUG-2及NTUG-3)的测量结果表明LAM-ICPMS是一种同时测定岩石样品多元素的快速有效方法.     

电感耦合等离子体质谱法测定岩石中47种元素的不确定度评定

采用封闭酸溶电感耦合等离子体质谱(ICP-MS)法测定岩石样品,分别对47种元素的测量结果不确定度进行评定。通过分析测试方法和测量条件,得到测量结果的不确定度主要由样品称量、样品溶液定容和样品溶液中元素浓度测量引入。在实验室质控条件下,对各不确定度分量进行评定和计算,其中随机因素导致的不确定度采用期间精密度试验综合评价,即采用A类方法评定。共完成了16个岩石国家标准物质(GBW 07103~GBW 07123)47种元素测量结果的不确定度合成,并参照GB/T 6379.2-2004,建立了含量w与扩展不确定度U之间的关系模型,运用这一关系模型可得到测量结果的不确定度估计值,只要测量过程本身或所使用的设备未变化,就不需要再重复进行不确定度评估。     

罗布泊地区环境样品中的放射性检测

随着核能的开发应用,研究环境中铀、钍、钾等长寿命放射性核素的放射性水平,对保护公众安全和生态环境具有重要意义。采用中子活化分析方法,对罗布泊地区环境样品作了放射性检测。根据该样品的比活度以及该样品的元素丰度与中国大陆地壳元素丰度的比较,表明罗布泊地区的地质放射性无明显的放射性异常,并可以作为建筑材料使用,符合GB6566-2001标准。     

岩石分析的化学方法

1981年 Pergamon 出版社出版的《岩石分析的化学方法》(第3版)共包括48章。前四章详细论述了岩石分析的一般特性:岩石物料的组成和取样、破碎及研磨、样品沾污源等一般性问题和特点(第一章);关于试样分解方法的详尽讨论(第二章);岩石分析的经典方法,例如主要组分和常见组分的一系列基本常规分析方法(第三章);系统完整地描述岩石样品的快速分析法,读者能够从中得到一个清晰全面的认识(第四章)。另外44章则是更深入细致地介绍单一元素或性质相类似的成组元素(如碱金属;钪、钆和稀土;锆和铪;钽和铌;氯、     

定南县废弃稀土矿区土壤中重金属元素Pb、Cr和Cu的测定

为了解废弃稀土矿土壤及周边土壤的重金属污染及对环境的影响,采用HNO3-HClO4湿法消解土壤样品,用原子吸收分光光度计及标准曲线法对消解样品中的重金属元素Pb、Cr、Cu含量进行了测定。根据国家土壤环境标准评价这3种重金属元素在该土壤中是否超标及超标程度。结果表明,赣州市定南县废弃稀土矿区及周边土壤中铅含量严重超标;矿区及周边土壤Cr含量未见超标;周边土壤铜含量接近超标。可见该废弃稀土矿区重金属元素污染以Pb为主,建议在土壤植物修复过程中着重考虑对Pb元素的清除。     

X射线荧光光谱法测定硅酸盐岩石中主次量成分结果异常时的质量控制北大核心CSCD

硅酸盐岩石样品的主次量成分分析(业内俗称硅酸盐成分全分析)是地质工作的重要内容。通过监测岩石内部成分含量的变化,可以了解相应元素在地壳内的迁移情况和变化规律、元素的集中和分散情况、岩浆的来源及可能出现的矿物相,可进一步解决矿体岩相分带、阐明岩石成因等问题;并且硅酸盐岩石主次量成分的含量是矿物定名时的重要依据[1]。因此,选择能准确测定硅酸盐主次量成分含量的方法非常重要。     

云南某金矿金与伴生元素的某些特征

采用中子活化分析方法研究了云南某金矿区内的硅化褐铁矿化石英砂岩类、辉绿岩类、灰岩类和黄铁矿样品的微量元素特征,并利用元素地球化学研究方法对元素间的相关关系进行了分析.结果表明,在该地区利用金的伴生元素来指导找矿,可提高金的找矿效益.     

Uranium and plutonium containing particles in a sea sediment sample from Thule, Greenland

Particles composed of radioactive materials and probably originating from US nuclear weapons were identified in sea sediment samples collected from Thule, Greenland, in 1997. The weapons were destroyed close to the Thule Air Base in 1968 in an aeroplane crash, which dispersed radioactive materials in the environment. The presence of particulate radioactive materials in the sediment samples was revealed by combining gamma-spectrometry and autoradiography. Isolation and separation of a radioactive particle from a bulk sample were performed using autoradiography, phosphor plate imaging and scanning electron microscopy. Using X-ray microanalysis as well as alpha and beta activity analysis, U and weapons-grade Pu were detected in the granular, brittle particle.     

Radionuclide detection by ion-chromatography and on-line ICP/MS and beta detection: Fission product rare earth element measurements

Separation and analysis of²³⁵U fission produced rare earth elements (REE) is described. Rare earth elements were separated using a high presure ion chromatographic separation where by each rare earth is isolated and individually detected. Detection is performed by inductively coupled plasma mass spectrometry (ICP/MS) and solid scintillation beta counting. The resulting detection methods allow complete evaluation of all stable (non-radioactive) and many radioactive REE fission products. The two detection methods (ICP/MS and Beta) illustrate how mass selective and radiometric data can be used to provide complimentary information regarding the isotopic characterization of radioactive samples.Pacific Northwest Laboratory is operated for the U.S. Department of Energy by Battelle Memorial Institute under Contract DE-AC06-76RLO 1830.     

Rapid radiochemical sample preparation for alpha spectrometry using polymer ligand films

Rapid radioanalytical methods are adversely affected by many different sample-matrix interferences, which make analyzing samples a difficult and time consuming process. A new method for preparing radioactive samples for analysis by alpha spectrometry has been demonstrated. In this technique, a selective extractive ligand is immobilized in a polymer film coated on a metal surface. This polymer ligand film is then used to extract plutonium and other radioactive analytes from solution over a short period of time. The prepared substrate is then counted directly by alpha spectroscopy in a small single detector alpha spectrometer. The method has been demonstrated for the analysis of americium and plutonium in liquid samples such as water and urine.     

Determination of radioactive pollution from an open landfill

Summary This paper presents a case study of radioactive pollution of groundwater caused by leachate from an open landfill. Alpha- and beta-radioactivity analysis of the leachate from different points in the region and associated fountain water from a village down stream were carried out during four seasons. The alpha- and beta-radioactivity concentrations were under the detection limit in all samples and ranged between 0.07 and 2.17 Bq/l, respectively. The beta-radioactivity concentration from ¹²⁹I, ¹³⁷Cs and ⁹⁰Sr individual radioisotopes were determined and their annual effective dose was calculated.     

Pre-concentration and determination of 90Sr in radioactive wastes using solid phase extraction techniques

This paper describes the use of IBC??s AnaLig^®Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate and recover strontium from radioactive waste samples. The use and effectiveness of AnaLig^®Sr-01 gel was successfully validated by analysis of International Atomic Energy Agency (IAEA 375) reference soil and National Physical Laboratory (NPL)?CHigh Alpha?CBeta (2003) liquid sample. The second part of this paper focuses on analysis of radioactive waste samples from nuclear power plant A1 Jaslovske Bohunice in Slovak Republic (NPP A1).     

Assessment of radiation risk and radon exhalation rate for granite used in the construction industry

Journal of Radioanalytical and Nuclear Chemistry - The results of the gamma spectrometry analysis of the 40 samples of highly radioactive granites used in the construction industry in Serbia are...     

The influence of statistical error in radioactivity counting on the precision of isotope dilution analysis,I

The influence of the statistical error in measuring radioactive samples in direct isotope dilution analysis is analytically studied for several practically important sets of conditions. Formulas are given to calculate the optimum amount of radioactive substance to be added in order to minimize the error involved. Both cases with negligible background count rates and cases where the background must be considered are treated. In some cases recommendations are given for the times of measurement of background, undiluted and diluted sample.     

Practical considerations regarding high resolution gamma-spectrometry measurements of naturally occurring radioactive samples

High-resolution gamma-spectrometry provides fast, accurate, non-destructive isotopic analysis of natural radionuclides in environmental samples. Low energy HPGe detectors (30%) with resolution less than 2.0 keV at 1332 keV of ⁶⁰Co and with linked analytical software, provide good peakto-background performance and accurate unfolding of multiplet regions. A procedure regarding high-resolution gamma-spectrometry measurements of naturally occurring radioactive samples is presented here including calibration, background interference, self-absorption, practical considerations and validation with respect to IAEA reference materials. Recommended peaks for quantitative measurements, deriving from the analysis of observed spectral interferences as well as from radioactive equilibrium considerations, are reported.