共查询到20条相似文献，搜索用时 46 毫秒
1.
悬浮液原子荧光光谱法测定化探样品中的痕量汞 总被引：3，自引：0，他引：3
拟定了将悬浮液技术与汞蒸气原子荧光光谱法相结合测定化探样品中痕量Ｈｇ的分析方法。控制悬浮液中试样粒度在２００目，试样质量浓度１５ｇ／Ｌ，用电磁搅拌和载气搅拌保证悬浮液分散稳定，水溶液标准作校正曲线，方法的检出限为６ｎｇ／ｇＨｇ。对水系沉积物国家标准物质中痕量Ｈｇ进行测定，结果与标准值相符，对含Ｈｇ０１０μｇ／ｇ的ＧＢＷ０７３０５（ＧＳＤ５）测定１１次，ｘ为０１０５μｇ／ｇ，ＲＳＤ为５４％。 相似文献
2.
催化光度法测定痕量锇 总被引：3，自引：0，他引：3
在０５ｍｏｌ／Ｌ的Ｈ２ＳＯ４介质中，Ａｓ（Ⅲ）存在下，Ｏｓ（Ⅷ）催化ＫＣｌＯ３氧化邻苯二酚紫褪色反应。反应受温度、反应时间影响，冷却及加入抗坏血酸可终止反应。据此，建立了一个测定痕量Ｏｓ（Ⅷ）的新方法。方法的灵敏度为２５７×１０－１０ｇ／ＬＯｓ（Ⅷ），测定范围为０～００９１μｇ／Ｌ，用地质管理样中锇的测定验证，结果与原结果相符 相似文献
3.
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
4.
预富集柱—离子色谱法测定高纯水中痕量氟和氯 总被引：3，自引：0，他引：3
在国产离子色谱仪上加装填充有季铵型阴离子交换剂的预富集柱，所设计的流路和方法可将测定Ｆ－和Ｃｌ－的检出限分别降至０１７μｇ／Ｌ和０２７μｇ／Ｌ。测定精密度好，ＲＳＤ＜５％，方法满足反应堆堆芯冷却水中痕量Ｆ－和Ｃｌ－的检测要求。 相似文献
5.
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
6.
三溴偶氮胂—锇—溴酸钾催化光度法测定微量锇 总被引：2，自引：0，他引：2
在酸性介质中Ｏｓ（Ⅳ）对ＫＢｒＯ３氧化三溴偶氮胂的褪色反应有明显的催化作用，借此反应可在水相中直接测定微量锇。方法灵敏度高，锇的质量浓度为１０～２００μｇ／Ｌ时符合比尔定律，表观摩尔吸光系数为９１８×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。方法已用于贵金属精矿中锇的测定 相似文献
7.
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
8.
9.
10.
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
15.
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
16.
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
17.
18.
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
19.
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
20.
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