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氢化物发生-电感耦合等离子体发射光谱法同时测定土壤中的痕量砷铜铅锌镍钒 总被引：1，自引：1，他引：0
土壤中砷的测定方法多采用氢化物发生-原子荧光光谱法(HG-AFS);电感耦合等离子体发射光谱法(ICP-OES)在多元素同时测定方面应用普遍,但测定砷的检出限稍高。氢化物发生技术与ICP-OES两者联用也多有研究,较大幅度降低了砷的检出限,已能实现砷锑铋汞等元素的同时测定。但联用技术只能应用于测定能够发生氢化反应的元素,无法实现易氢化元素和难氢化元素的同时测定。本文通过改进ICP-OES仪器的进样装置,采用氢化反应气与ICP-OES雾化气双管路同时进样的方法,实现了一次溶样、一台设备同步测定样品中的砷和多种金属元素。土壤样品经氢氟酸、硝酸、高氯酸、盐酸溶解后,用10%盐酸提取,用硫脲-抗坏血酸溶液将砷元素预还原为+3价后双流路同时进样测定。对于溶液中共存的离子,高于1.0mg/L的La和Dy对砷测定有干扰;低于50.0mg/L的K、Na、Ca、Mg、Fe,低于20.0mg/L的Pb、Mo、Zn、Cu、Ba、Ti、Mn、Ni、Sr、V、Cr,低于10.0mg/L的Co、Ag、U、Cd、Li、Au对砷测定无影响。本方法提高了砷的测定灵敏度,又充分利用多元素同测的优势,实现了同时测定易氢化的痕量砷和难氢化的铜、铅、锌、镍、钒等元素。方法精密度高(RSD5%),经土壤标准物质验证方法可靠,适合痕量砷与其他元素的同步测定。 相似文献
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《物探化探计算技术》2015,(2)
同步震源地震采集技术,因其任意两个震源之间激发时间的间隔不受任何门限值的制约,可以进行同步激发,与常规采集技术相比,在相近的时间内能够采集到更多的地震记录,从而大大缩短了采集周期,提高采集效益,是近年来国外发展最快的高效采集技术。这里首先介绍了该技术的发展现状,其次以独立同步扫描(ISS)、距离分开同步扫描(DSSS)、HPVA和V1等同步可控震源特色采集技术为例,从其勘探设计出发,结合各自的采集技术、数据分离技术以及野外测试情况进行了介绍,最后对各种高效采集技术的优势进行了对比总结。 相似文献
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铀系核素210Pb一210Bi-210Po目前通常采用相对独立的分析技术,三核素分别进行测定,并存在一些技术问题需要解决.文献报道的三核素联测技术需要使用多种昂贵的测试设备和示踪剂,或者制源体系抗干扰能力较弱且分析周期较长.本文研究了210Bi、210Po同时且定量恒温自沉积于铜箔的最佳制源条件,建立了双样-两次铜箔恒温自沉积制源-总α、总β同时计数法快速联合测定岩石、土壤及沉积物样品中210Pb-210Bi-210Po的分析技术.结果表明,当铜镀片面积为3.14 cm2,盐酸浓度为0.5 mol/L,氯化钠浓度为3.5 mol/L,溶液体积为20 mL,恒温90℃,振速为120 r/min,振幅20 mm,制源70 min,210Bi和210Po可同步定量自沉积且210Pb不沉积.在抗坏血酸存在下,大量共存元素不干扰自沉积.方法的精密度优于5％,全程加标放化回收率在99.5％～100.5％之间.该联测技术采用的制源体系抗稳定铋干扰能力较强,回收稳定,分析周期短,仅需一台国产测试设备并无需示踪剂即可完成三核素联合测定,同时也适合于三核素的独立测定. 相似文献
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引言分子荧光是非地震找油的重要指标之一。通常采用固定波长法测土壤中的发荧光物质，此方法对发荧光物质的定性、定量分析比较困难，而且谱峰重叠严重，难以分辨，采用同步扫描技术可以使光谱简化，谱带变窄，在同时测定多种芳烃时，大大提高了分辨率。由于多环芳烃的斯多克位移在2-5urn之间，采用同步扫描时，激发波长与荧光波长差往往在3～5urn之间，这时溶剂的干扰非常严重。采用偏振技术可有效地抑制散射光的干扰，提高检测的灵敏度。2实验部分ZI方法原理许多芳香族化合物在室温和77K下具有发荧光的性质，在紫外线的照射下能够发出… 相似文献
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经前人研究结果表明,珠江口盆地M地区常规叠后波阻抗较难识别储层和反映储层物性。使用叠前同步反演方法,即利用叠前CRP道集和测井信息,采用Fatti方程的改进形式进行反演,可同时获得纵波阻抗、横波阻抗、密度等弹性参数。结果表明,密度属性能很好地区分储层,反映储层物性,目的层灰岩和砂岩储层的沿层密度属性很好地反映了储层横向变化规律。实钻结果表明,预测结果与井实测结果吻合度较高,表明利用叠前同步反演技术进行珠江口盆地M地区储层预测是可行的。 相似文献
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面向地震综合观测需要,自主研制了窄线宽光纤光栅谐振腔,并将其作为核心传感元件,发展了一种基于有效腔长的光纤应变、地震波和温度多参量同步测量新方法。采用边带扫频激光技术实现了高精度多参量光纤信号同步解调,研制出了光纤地壳形变、地震与温度多参量探头,并开展了多参量地震综合观测实验。实验结果表明,所研制的光纤多参量传感系统应变与温度测量分辨率分别达到4.7×10^-10和6×10^-5℃,能够同时记录到清晰的固体潮汐信号、地震波信号以及环境温度扰动,有望为多参量地震同步观测提供先进的技术手段。 相似文献
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Mass Fractions of Forty‐Six Major and Trace Elements,Including Rare Earth Elements,in Sediment and Soil Reference Materials Used in Environmental Studies 
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下载免费PDF全文 Željka Fiket Nevenka Mikac Goran Kniewald 《Geostandards and Geoanalytical Research》2017,41(1):123-135
Development of new techniques, enabling simultaneous determination of large numbers of elements in environmental samples, can force analysts to use certified reference materials that do not contain all the elements of interest. In this paper, the mass fractions of forty‐six major and trace elements, including rare earth elements (REE), are presented in one soil (NCS DC 77302 also known as GBW 07410) and five sediment (Metranal‐1, IAEA 405, MESS‐3, NCS DC 73309 also known as GBW 07311 and NCS DC 75301 also known as GBW 07314) certified reference materials determined by high resolution inductively coupled plasma‐mass spectrometry. The selected certified materials represent a spectrum of geological matrices often analysed in environmental studies. Measured elements include certified elements, elements listed with information values as well as new elements absent from certificates, including REEs and some other elements. REE + Y mass fractions in the river sediment reference material Metranal‐1 are reported for the first time. The results obtained are in agreement with available certified or information values. 相似文献
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Valentina G. Tsimbalist Gennady N. Anoshin Valentin N. Mitkin Ljudmila I. Razvorotneva Nadezhda P. Golovanova 《Geostandards and Geoanalytical Research》2000,24(2):171-182
Some recent experiments on the determination of Au and the platinum-group elements (PGE) in geochemical samples are reviewed. Emphasis is given to the determination of ultra-low levels of PGE concentrations in resistant matrices, including chromites, molybdenites and ultrabasic ores. The problems and features of PGE determination in samples of various chemical composition are considered. For each sample type studied, a series of sample preparation techniques are proposed. These techniques included acid digestion, fusion with sodium peroxide, cold sintering with an oxidizing mixture of Na2 O2 + Na2 CO3 and also oxidizing fluorination with bromine trifluoride. A new approach for preparing geochemical material prior to digestion, based on mechano-chemical activation with simultaneous hyperfine grinding, is proposed and studied. The instrumental determination of PGE contents was carried out directly by AAS from extracted organic phases. It was found that a combination of digestion processes was required to achieve geochemical background levels of Au and PGE concentrations with the following detection limits: Pd, Rh - 1 ng g−1 , Pt, Ru - 10 ng g−1 , Au - 0.2 ng g−1 , Ag - 0.1 ng g−1. The uncertainty in PGE and Au determination in geochemical samples is dependent on metal concentration, and also on their distribution in samples. The total analytical uncertainty of the proposed method is between 15-30%. 相似文献
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Jean S. KANE 《Geostandards and Geoanalytical Research》1989,13(2):205-215
Analytical data are presented for the determination of Ag, Bi, Cd, Co, Cu, Mn, Ni, Pb, Zn in 60 geochemical reference samples by simultaneous multi-element atomic absorption spectrometry with flame atomization. The samples include rocks, sediments, coal ash, Mn nodules and ores. Accuracy and precision of the analysis are evaluated statistically. 相似文献
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多环芳烃单体同位素分析进展 总被引：5，自引：0，他引：5
多环芳烃(PAHs)单体同位素组成是辨识这类污染物来源,评价其在环境中生物可降解性的重要手段。准确高精度的PAHs单体同位素比值测定有赖于样品预处理方法的改进和相应仪器分析技术的提高。文章综合评述了近年来PAHs单体同位素分析中的预处理方法研究进展,主要包括索氏提取、加速溶剂萃取等提取方法和硅胶、氧化铝柱色谱、固相萃取、凝胶渗透色谱、高效液相色谱、薄层色谱等净化方法;介绍了PAHs单体同位素组成的气相色谱-同位素比值质谱分析方面的研究进展,包括色谱柱头压、进样时间、PTV大体积进样技术等仪器参数的选择和校准同位素内标的选择等数据处理方式。 相似文献
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Brian Klinkenberg 《Mathematical Geology》1994,26(1):23-46
An in-depth review of the more commonly applied methods used in the determination of the fractal dimension of one-dimensional curves is presented. Many often conflicting opinions about the different methods have been collected and are contrasted with each other. In addition, several little known but potentially useful techniques are also reviewed. General recommendations which should be considered whenever applying any method are made. 相似文献
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An ion exchange flow injection method is presented for the simultaneous determination of bromide and iodide based on the catalytic reaction during the oxidation of Pyrocatechol Violet by hydrogen peroxide in strongly acid solution. Bromide and iodide in sample solutions are concentrated when they flow through the ion exchange column; they are removed and separated with sodium nitrate eluant flowing through the column, and are monitored spectrophotometrically at 555 nm. All possible anionic interferences were studied. The procedure has been applied successfully to the determination of bromide and iodide in some Chinese standard reference samples. The limits of detection are 0.2 ppm and 0.4 ppm of bromide and iodide respectively in soils and stream sediments. 相似文献
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Degradation of common pharmaceuticals and personal care products in mixed solutions by advanced oxidation techniques 总被引：6，自引：6，他引：0
R. R. Giri Ph.D. H. Ozaki D.Eng. S. Ota R. Takanami M.Eng. S. Taniguchi M.Eng. 《International Journal of Environmental Science and Technology》2010,7(2):251-260
Widespread detection of pharmaceutical compounds in water environment has been a serious concern recently, while conventional sewage treatments are ineffective for their elimination. But, advanced oxidation techniques are very promising to remove varieties of organic contaminants in water. This research aims to elucidate oxidation potentials of sixteen commonly used pharmaceutical compounds in mixed solutions by seven advanced oxidation techniques in laboratory batch experiments. The removal profiles exhibited four distinct patterns: a) easily degradable by all seven techniques, b) not easily degradable by all seven techniques, c) easily degradable by ozone-based techniques, but not by ultraviolet radiation-based techniques and d) easily degradable by ultraviolet radiation-based techniques, but not by ozone-based techniques. Ozone-based techniques rather than ultraviolet radiation-based techniques were very powerful for simultaneous removal of the compounds efficiently. Moreover, ozonation combined with ultraviolet radiation was the most appropriate technique for simultaneous removal of the tested compounds efficiently. Increased ozone dissolution and decomposition with ozone-based techniques did not always enhance the compounds’ removal. Physicochemical properties of the compounds and solution pH also presumably played an important role on the removal which merits further attention. 相似文献
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本文叙述了电感耦合等离子体原子发射光谱法(ICP-AES)测定硅酸盐岩石中的主要元素的分析方法及结果。我国ICP-AES对痕量分析工作已广泛开展,但在硅酸盐主要元素分析方面如何发挥仪器潜力的报导并不多。本文的目的是提供一个同时测定硅酸盐 相似文献
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铊的原子吸收光谱分析进展 总被引：5，自引：1，他引：4
对近年来用原子吸收光谱法测定铊进行了总结评述。重点介绍了用原子吸收法测定铊时 ,基体改进剂、进样方式、反应机理以及预富集技术对提高方法灵敏度的作用。引用主要文献 43篇 相似文献