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1.
氢化物发生-电感耦合等离子体发射光谱法测定铀矿地质样品中痕量硒 总被引：3，自引：2，他引：1
采用氢化物发生技术测定地质样品中的硒时,需要考虑样品的溶解、Se价态的预还原以及抑制共存离子的干扰。本文采用硝酸-盐酸-氢氟酸-高氯酸体系快速溶解样品,直接加入浓盐酸煮沸将六价硒还原为四价硒,将氢化物发生器与电感耦合等离子体发射光谱仪联用测定了铀矿地质样品中的痕量硒。样品中除了Cu2+其他离子的含量均不干扰硒的测定,通过在试液中加入铁盐溶液或在硼氢化钠还原剂中加入铁氰化钾抑制了Cu2+的干扰。方法检出限为0.12μg/L,精密度(RSD)小于5%。与前人报道的方法相比,本方法检出限较低,操作简单快速,冲洗30 s可消除记忆效应,适合批量铀矿地质样品中痕量硒的测定。 相似文献
2.
巯基棉分离富集-荧光分光光度法测定地下水中的痕量硒 总被引：4，自引：2，他引：4
在盐酸介质中,利用巯基棉分离富集地下水中痕量硒,然后在HC l-HNO3混合酸溶液及沸水浴加热条件下解脱富集的硒。通过测定2,3-二氨基萘与Se(Ⅳ)反应生成4,5-苯并苤硒脑的荧光强度,进而实现地下水中痕量硒的测定。实验表明,荧光光度法测定硒的线性范围为0~1.0μg,最低检测浓度为0.03μg/L,应用此法测定0.1μg/L硒的地下水,相对标准偏差小于7%,回收率达91%~105%,可满足地下水中硒的测定要求。 相似文献
3.
富氧空气-乙炔火焰原子吸收光谱法测定地质样品中的钒 总被引：3，自引：0，他引：3
利用测试液中当铝离子浓度超过钒离子浓度两倍以上，铝对钒的吸收信号增感基本恒定，且能较好地克服其它元素的化学干扰，建立了富氧空气-乙炔火焰原子吸收光谱法测定地质样品中痕量钒的方法。方法的检出限LD为0．33mg／L。应用于国家一级地质标准物质中痕量钒的测定，结果与标准值相符。对GBW 07303水系沉积物样品测定6次，ω^-(V)=119．0μg/g，RSD为4．5％。 相似文献
4.
地下水中钙和镁的离子色谱法同时测定 总被引：2，自引：0，他引：2
改进了离子色谱分析地下水中钙和镁的方法。以IonPac CS12A为分离柱,稀盐酸为淋洗液,电导检测器检测,对地下水中的锂、钾、钠、钙和镁进行同时测定。方法具有较宽的线性范围和较高的灵敏度,钙、镁的浓度分别在0～500mg/L和0～250mg/L内呈良好的线性关系;钙的检出限为1.50μg/L,镁的检出限为0.89μg/L。对不同浓度钙、镁水质标准样品进行分析测定,同时对实际样品进行不同稀释倍数分析验证,方法精密度(RSD,n=8)为0.19%～1.89%,无显著的基体效应影响。方法可满足全国地下水调查评价规范要求,适于地下水样品中锂、钾、钠、钙和镁离子的同时测定。 相似文献
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建立了高温燃烧水解-离子色谱测定植物样品中不同含量范围氟的分析方法,色谱条件为Dionex IonPacAS18分离柱(4 mm×250 mm),Dionex IonPac AG18保护柱(4 mm×50 mm),ASRS ULTRAⅡ自动再生微膜抑制器,电导检测器。采用纯水作为吸收介质,使样品溶液与标准溶液基体一致,过滤后可直接测定。样品溶液中常见的Cl-、NO3-、SO24-、PO43-、CO23-、HCO3-等阴离子不干扰F-的测定。为消除样品热解过程中产生的乙酸干扰,对氟含量较高(xx～xxxμg/g)的样品,采用20 mmol/L的NaOH淋洗液等度淋洗,进样体积为25μL;对氟含量较低的样品(0.x～xμg/g),进样体积为100μL。方法具有较宽的线性范围和较好的稳定性,检出限为0.5 mg/kg,适用于痕量分析;应用于灌木枝叶和茶叶等4个氟含量较高(xx～xxxμg/g)的植物标准物质的测定,相对标准偏差(RSD)<6%(n=6);应用于低氟的小麦粉和大米粉样品测定,加标回收率为90%～110%,可以满足不同氟含量植物样品中氟测定的需要,具有自动化程度高、操作简单、对环境友好等特点。 相似文献
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随着富硒产品关注度越来越高,对土壤中硒含量测定的研究也越来越受到人们的重视。应用传统电感耦合等离子体质谱法(ICP-MS)测定土壤样品中的硒时,受到的基体效应和多原子离子干扰比较显著,准确测定硒含量的难度较大。本文建立了采用50%王水-沸水浴消解体系,ICP-MS测定土壤样品中硒含量的方法,实验中采用动能歧视模式(KED)消除质谱干扰,选用~(103)Rh元素作为在线加入内标以消除仪器信号漂移。用该方法对有证土壤标准物质进行分析,其结果均在不确定度范围内,测定值与认定值的相对误差介于-2.01%～2.99%之间,相对标准偏差(RSD)小于6.60%,检出限为0.012μg/g,测定下限为0.048μg/g。应用该方法与国家环境保护标准方法(HJ680—2013)对20个土壤实际样品进行比对分析,其结果基本一致。该方法适合于分析测定地质等行业大批量土壤样品中的硒。 相似文献
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碱性模式氢化物发生—原子荧光光谱法测定土壤中的痕量硒 总被引：3，自引：1，他引：3
土壤样品经王水分解，转化成HCl溶液，再用NaOH溶液调至碱性，样品溶液首先与KBH4混合，然后与酸作用完成氢化物发生，用原子荧光光谱法测定样品中的痕量硒。方法检出限为0.01μg/g。线性范围为1－200μg/L，样品中硒的含量为0.082μg/g和0.34μg/g时，RSD（n=12)分别为4.9%和2.9%。方法经土壤国家一级标准物质中硒的测定验证，结果与标准值相符。 相似文献
8.
利用铜(Ⅱ)与铜试剂反应生成鳌合物沉淀的同时,能将痕量汞(Ⅱ)共同沉淀出来的特性,将汞(Ⅱ)分离富集,电感耦合等离子体发射光谱法测定地下水中汞的含量。在汞标准溶液中,加入不同量的铜和铜试剂测定汞的真实含量,最终确定铜和铜试剂最佳加入量。通过优选分析线、背景恰当扣除处理,水溶液体积由200 mL浓缩至5 mL,富集40倍后汞的检出限可达0.1μg/L。方法用于测定国家标准物质GBW(E)080006和实际样品,测定值与标准值、国家标准方法测定值一致,均在允许误差范围内。方法精密度(RSD,n=12)小于10%,可满足地下水中痕量汞的测定要求。 相似文献
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基于0．02mol／L HCl介质中，痕量钴(Ⅱ)对重铬酸钾氧化偶氮胂Ⅲ褪色反应的催化作用，建立了测定痕量钴(Ⅱ)的动力学光度法。钴(Ⅱ)质量在0～4．0μg/L范围内服从比尔定律，方法检出限为0．076μg/L，在25mL溶液中，测定0．1μg钴(Ⅱ)的相对标准偏差为3．8％(n=11)。讨论了酸度、反应物浓度、温度、反应时间、干扰离子等因素的影响。研究了反应的最佳条件，并测定了一些动力学参数。催化反应的表观活化能为40．73kJ／mol。此法可用于井水、蜂蜜和维生素B12中钴(Ⅱ)的测定，相对标准偏差为1．8％-5．7％，标准加入回收率为99．6％～104．2％。 相似文献
11.
Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
12.
Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414. 相似文献
13.
The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
14.
Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level 相似文献
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正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7), 相似文献
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正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci- 相似文献
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正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli- 相似文献
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正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.) 相似文献