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1.
在０．００２％溴化十四烷基三甲胺（ＴＴＭＡＢ）－２０％ＨＣｌ体系中，Ｓｎ有一灵敏的吸附波，峰电位在－０、４７Ｖ（ｖｓ．Ａｇ／ＡｇＣｌ），线性范围２～１０００ｎｇ／ｍｌ。体系可用于岩石、土壤样品中微量Ｓｎ测定；机理研究表明，溴化十四烷基三甲铵通过诱导吸附ＳｎＣｌ＾２－４提高测定的灵敏度。 相似文献
2.
探讨了各种类型的表面活性剂对Ｓｃ－铜铁试剂体系的增敏效应；观察到在ｐＨ９．０的ＮＨ＿４ＯＨ－ＮＨ＿４Ｃｌ缓冲介质中，溴化十四烷基三甲铵使该体系催化波灵敏度提高了２５倍。峰电位在－１．５０Ｖ（ｕｓ．Ａｇ／ＡｇＣｌ），峰高与Ｓｃ浓度在２～４０ｎｇ／ｍｌ呈线性关系，检出限１ｎｇ／ｍｌ；用拟定的方法测定了岩石样品中的痕量Ｓｃ；并对其极谱性质和表面活性剂增敏机理进行了探讨。 相似文献
3.
二溴羟基苯基荧光酮荧光光度法测定水中微量锰 总被引：1，自引：0，他引：1
用荧光光度法研究了二羟基苯基荧光酮（ＤＢＨＰＦ）－溴化十六烷基三甲铵（ＣＴＭＡＢ）－Ｍｎ＾２＋体系的最佳测定条件。在ＰＨ１０．０的ＮＨ３．Ｈ２Ｏ－ＮＨ４Ｃｌ介质垢检出限为０．３ｎｇ／ｍｌ，适用于江湖水中微量锰的测定。 相似文献
4.
5‘—硝基水杨基荧光酮与锆显色反应及其应用 总被引：8，自引：0，他引：8
在０．０８￣０．１０ｍｏｌ／Ｌ ＨＣｌ介质中，溴化十六烷基三甲铵（ＣＴＭＡＢ）存在下，Ｚｒ（Ⅳ）与５＇－硝基水杨基荧光酮（５＇－ＮＳＦ）发生显色反应，形成１：４的桔红色络合物，λｍａｘ＝５４０ｎｍ，ε为１．４６×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１，Ｚｒ（Ⅳ）含量在０￣０．５ｍｇ／Ｌ符合比尔定律。方法用于氧化铝及陶瓷釉料中锆的测定，结果与ＩＣＰ－ＡＥＳ法相符，ＲＳＤ（ｎ＝５）在１．３％￣３．７％。 相似文献
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6.
甲基异丁基甲酮萃取－石墨炉平台原子吸收法测定地质样品中痕量硒和碲 总被引：1，自引：1，他引：1
样品经ＨＮＯ＿３－ＨＦ－ＨＣｌＯ＿４分解，在５．４ｍｏｌ／Ｌ的ＨＣｌ介质中，以抗坏血酸为还原剂用甲基异丁基甲酮同时萃取样品中的Ｓｅ、Ｔｅ。以Ｐｄ和Ｎｉ作混合基体改进剂，使用自制的涂锆石墨平台直接测定有机相中的Ｓｅ、Ｔｅ。方法的检出限分别为０．２１×１０￣（－９）ｇＳｅ，０．１３×１０￣（－９）ｇＴｅ；测定０．０６ｇＳｅ、０．０３ｇＴｅ的ＲＳＤ（ｎ＝１１）分别为７．０％和８．９％。 相似文献
7.
表面活性剂对钪—铜铁试剂络合吸附波的增敏效应 总被引：1，自引：0，他引：1
探讨了各种类型的表面活性剂对Ｓｃ－铜铁试剂体系的增敏效应；观察到在ＰＨ９．０的ＮＨ４ＯＨ－ＮＨ４Ｃｌ缓冲介质中，溴化十四烷基三甲铵使该体系催化波灵敏度提高了２５倍。峰电位在－１．５０Ｖ，峰高与Ｓｃ浓度在２－４０ｎｇ／ｍｌ呈线性关系，检出限１ｎｇ／ｍｌ；用拟定的方法测定了岩石样品中的痕量Ｓｃ；并对其极谱性质和表面活性剂增敏机理进行了探讨。 相似文献
8.
异烷基膦酸二丁酯色层柱分离原子吸收法测定矿石中金 总被引：1，自引：0，他引：1
以仿ＸＡＤ－７吸附树脂为担体，异烷基膦酸二丁酯（５２０８）为固定相的色层粉，在５％－５０％王水和０．５ｍｏｌ／Ｌ－６ｍｏｌ／ＬＨＣｌ介质中可定量吸附金，用８０℃３ｇ／Ｌ硫脲溶液解析后，原子吸收法进行金的测定。 相似文献
9.
研究了用感耦等离子体发射光谱（ＩＣＰ－ＡＥＳ）测定纯氧化镧中Ｃｅ，Ｐｒ，Ｎｄ，Ｓｍ，Ｙ，Ｆｅ，Ａｌ，Ｃａ，Ｍｇ和Ｓｉ１０个杂质元素的方法。考察了基体镧的光谱干扰，共存元素间光谱干扰及校正方法，方法检出限为０．０００５－０．０３９μｇ／ｍｌ；标准加入量１μｇ／ｍｌ时，回收率为９５％－１０６％；１０μｇ／ｍｌ的标准溶液，测定１０次，ＲＳＤ为０．２４％－１．０１％。方法简单，快速，不震分离富集，适用于氧 相似文献
10.
二溴羟基苯基荧光酮与铝显色反应的研究及应用 总被引：1，自引：0，他引：1
在ｐＨ为６．５的ＨＡｃ－ＮａＡｃ介质中，ＣＰＢ存在且经６０～７０℃加热，Ａｌ￣３＋与二溴羟基苯基荧光酮（ＤＢＨ－ＰＦ）４ｍｉｎ即完成显色反应，形成１：２紫红色络合物，吸光度至少稳定２４ｈ，最大吸收峰位于５６８ｎｍ处，摩尔吸光系数为１．１８×１０￣５，Ａｌ量在０～０．２μｇ／ｍｌ范围内符合比不定律。方法已应用于岩矿中微量Ａｌ的直接测定，其结果与标准值吻合较好，ＲＳＤ（ｎ＝５）均＜３％。 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.
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
15.
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
17.
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
18.
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
19.
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
20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of 相似文献