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1.
超痕量铀光度分析的若干进展 总被引：1，自引：0，他引：1
本文综述了近十多年来超痕量铀光度分析方法的一些进展,包括激光液体/固体荧光法和分光光度法。由于激光技术、光纤技术、时间分辨技术以及多元离子缔合物分光光度体系的应用,大大提高了铀分析的灵敏度,应用这些方法已能满意地测定低至10~(-12)—10~(-9)g/g的铀。 相似文献
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综述了近年来我国铜的光度分析的新进展，内容包括经测铜方法的改进，新体系及新试剂，结新分光光度法，催化光度法，导数光度法，荧光光度法，化学发光法，流动注射光度法，共引用文献２５９篇。 相似文献
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氟试剂分光光度法测定氟化物的方法分析 总被引：4，自引：0，他引：4
在氟试剂分光光度法的基础上,从吸收光谱、比色皿选择、各试剂的pH值及用量对吸光度的影响、工作曲线等方面,分析了影响测定氟化物的因素,并对氟试剂分光光度法提出了改进意见。 相似文献
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吸光光度法(Absorption photometry)由于具有简便、快速、灵敏、选择性好,且可测元素多等优点,到目前人们仍乐于采用。近年来又出现了导数分光光度、双波长分光光度、流动注射分析、光导纤维化学传感器和以微电流扩展标尺的全差示光度法等新技术,致使这门分析技术至今仍具有强大的生命力。 差示光度法早已成为吸光光度法的一个重要分支。1949年Hiskey首次提出时主要用于高含量组分的精确测定。为了提高低含量组分的测定精度, 相似文献
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双波长分光光度法中负峰效应 总被引：1，自引：0，他引：1
本文以二溴苯基荧光酮光度法测Cr,铍试剂Ⅲ光度法测Be以及二甲苯胺蓝Ⅱ光度法测Mg等体系为例,对分光光度分析中负峰出现和可测的条件为C_R·L相似文献
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4,5-二溴苯基萤光酮和CTMAB分光光度法测定锰 总被引：1，自引：0，他引：1
锰的分光光度测定常用的有高锰酸盐法。最近有人合成了4,5-二溴苯基萤光酮(简称Br-PF),已用于铌、钨、钼、锡、钛、铬、钒等的分光光度分析。本文在pH9,用Br-PF-CTMAB光度法测定锰(Ⅱ),灵敏度高,ε_(590)=1.37×10~5,已应用于矿石及水样中微量锰的测定,得到了满意的结果。 实验部分 相似文献
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用滤纸负载固相反射散射分光光度法测定银 总被引：2，自引：0，他引：2
探讨一种新的固相分光光度法——固相反射散射分光光度法，通过滤纸对银缔合物的分离富集，研究Ag与对二苯胺基卡叉若丹宁形成的缔合物在滤纸相的反射散射吸光度(Ag)，从而测定样品中的Ag。实验结果表明，在酸性条件下，Ag(Ⅰ)与若丹宁在表面活性剂介质中形成稳定的缔合物，可以被均匀地抽滤到滤纸相表面，该缔合物最大吸收波长(λ)为590nm；Ag(Ⅰ)质量浓度在O～12μg/25mL范围内，与吸光度呈线性关系；Ag的检出限为0．05μg/mLL，相对标准偏差(RSD)为4．3％。 相似文献
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微量铀的分析,近年来国内外分析方法很多,国内以采用分光光度法较为普遍,经过不同手段分离后,用偶氮胂Ⅲ、偶氮氯膦Ⅲ、溴代PADAP等显色剂显色分光光度测定。其他也采用小体积容量法、极谱法、荧光光度法等。各类仪器测定的方法,其 相似文献
9.
金的分光光度分析的进展 总被引：1，自引：0，他引：1
分光光度法在金的测定中应用广泛。随着高灵敏度显色剂的合成和新的测定方法的出现,该法已应用到化探样品中痕量金的测定。本文收集文献70篇介绍了近年来金的分光光度分析的进展情况, 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
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