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析相萃取光度法测定法质样品中痕量钯 总被引:3,自引:0,他引:3
研究了表面活动剂加醇析相对钯-硫代米Chi酮络合物的萃取行为,建立了痕量钯的光度测定方法。析相对Pd的萃取回收率为99.5%,富集倍率搂25。络合物的λmax=530nm,形成后至少稳定2h,ε达2.6×10^6L·mol^-1·cm^-1,线性范围1.4 ̄40.0μg/LPd(Ⅱ),检出限是1.4μg/L,对于10μg/LPd测定11次,计算相对标准偏差为4.4%。方法已用岩矿中痕量钯的测定,结 相似文献
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光度法测定痕量钛的研究 总被引:6,自引:1,他引:6
基于痕量Ti(Ⅳ)在稀H2SO4介质中对EDTA还原Cr2O2-7褪色反应的抑制作用,建立了测定痕量Ti(Ⅳ)的光度法。测定范围为24~24μg/L,检出限为106×10-7g/LTi(Ⅳ)。结合萃取分离富集技术,方法用于测定人发及茶叶样品中的痕量Ti(Ⅳ),结果与标准值相符,加标回收率在95%~100%,RSD(n=6)为11%~20%。 相似文献
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研究了在KH2PO4Na2B4O7缓冲介质中,痕量镍催化H2O2氧化胭脂红褪色的指示反应及动力学条件,测定了反应活化能,建立了动力学光度法测定痕量镍的新方法。方法检出限为240×10-8g/L,测定范围为008~24μg/L。结合丁二酮肟正丁醇萃取分离,实现了对铝合金标样中痕量镍的测定,RSD(n=6)小于3%。 相似文献
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悬浮液进样—石墨炉原子吸收测定钒钛磁铁矿中痕量镓 总被引:5,自引:0,他引:5
研究了悬浮液进样_石墨炉原子吸收测定钒钛磁铁矿中痕量镓的分析方法。以Ni(Ⅱ)作为基体改进剂时,可直接用镓标准溶液进行校准。样品粒度<38μm、悬浮液中试样质量浓度在01~80g/L、含镓质量浓度不超过100μg/L时呈良好线性关系,检出限为24μg/L镓。用所拟方法测定了含镓量在16~42μg/g的标准矿样,结果与标准值相符,6次平行测定的相对标准偏差不超过9%,满足痕量分析的要求。 相似文献
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5—(偶氮苯)—8—(4—硝基—1—重氮苯)—氨基喹啉与钯的显色反应及应用 总被引:10,自引:1,他引:9
在弱碱性介质中,乳化剂-OP存在下,5-(偶氮苯)-8-(4-硝基-1-重氮苯)-氨基喹啉(PANPAQ)与钯发生显色反应,生成nPANPAQ∶nPd(Ⅱ)=2∶1的蓝色络合物,最大吸收峰位于640nm,摩尔吸光系数为1.08×105L·mol-1·cm-1,钯的质量浓度在0~600μg/L符合比尔定律。所考查的54种共存离子,对测定Pd(Ⅱ)基本无影响。方法已用于钯催化剂中Pd(Ⅱ)的测定,结果与原子吸收法相符,5次测定的RSD在1.3%~1.5%。 相似文献
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二溴羟基苯基荧光酮光度法测定锌 总被引:2,自引:0,他引:2
在pH114的Na2HPO4NaOH缓冲介质中,表面活性剂溴化十六烷基吡啶(CPB)及TritonX100存在下,锌与二溴羟基苯基荧光酮发生显色反应,生成的络合物最大吸收波长在610nm处,摩尔吸光系数178×105L·mol-1·cm-1。NaPO3的存在可提高方法的灵敏度与选择性。比尔定律范围是0~320μg/L,可不经分离直接测定硫铁矿中锌。对硫铁矿中w(Zn)为002%或04%的样品进行6次平行测定,其RSD为163%~53%。 相似文献
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催化动力学光度法测定痕量钛的研究 总被引:2,自引:0,他引:2
在氨性介质中,痕量Ti(Ⅳ)催化KIO4氧化靛红的褪色反应。褪色程度与Ti(Ⅳ)的浓度在0~8μg/L线性相关;对于靛红褪色反应为零级,对于Ti(Ⅳ)该反应为一级;测定该反应的表观活化能为7045kJ/mol;反应速率关系式是-dCR/dt=KCTi。基于该反应,建立测定痕量Ti的方法,其检出限505×10-9g/L;RSD(n=6)<52%,干扰可经伯胺N1923萃取分离消除。方法用于人发样中痕量Ti(Ⅳ)的测定,结果与极谱法相符。 相似文献
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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
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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
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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
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Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
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正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.) 相似文献
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正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.) 相似文献
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正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.) 相似文献
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正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus., 相似文献
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正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an 相似文献