共查询到20条相似文献，搜索用时 62 毫秒
1.
作者发现;在NH_4Cl-NH_3·H_2O介质中,有活化剂邻菲啰啉存在时,Cu(Ⅱ)对(NH_4)_2S_2O_8氧化氨基黑10B有显著的催化褪色作用。基于此,建立了催化光度测定痕量Cu的新方法。方法用于环境水、高纯铝、超基性岩等试样中痕量Cu的测定,结果与原值(或标准值)符合。 1 试验方法 相似文献
2.
铬天青B(CAB)作为一种高灵敏显色剂,近年又用于Sc、Th、Pd、Ti、Ga和Ni等元素的光度分析。本文研究了Cu(Ⅱ)与CAB、喹啉、溴化十六烷基三甲基铵(CTMAB)形成蓝绿色四元配合物的显色反应,此显色体系灵敏、稳定性好,方法可用于矿石中痕量Cu的测定。 1 实验方法 吸取5μg Cu(Ⅱ)溶液于25ml比色管中,加入l滴对硝基酚,用稀NaOH调至黄色,再用稀HCl调至无色。加入1.5ml 2％的喹啉,0.80ml 0.04％ 相似文献
3.
在0.2mol/L的H_2SO_4介质中,cu(Ⅱ)与苦胺PT显色剂生成1:1络合物。λImax=550nm,表观摩尔吸光系数为2.10×10~4L·mol~(-1)·cm~(-1),乙醇的存在对显色体系有明显的增敏作用。线性范围在0-45μgCu/25ml。除较大量的Fe(Ⅲ)、Ti(Ⅳ)、V(V)、Nb(V)、Zr(Ⅳ)和Ga(Ⅲ)外,其它共存元素不干扰本法测定。方法可用于矿石中0.01-xx％的Cu的测定,结果稳定可靠。 相似文献
4.
催化光度法测定矿石中痕量金 总被引：1，自引：0，他引：1
本法研究了金(Ⅲ)在1.2mol·L~(-1)硫酸中对铈(Ⅳ)-汞(Ⅰ)体系的催化作用。选择和确定了试剂最佳浓度、催化时间、加热温度,观察了共存离子等的影响。检出限为2.0gAu。金浓度在2.5—250ng/10ml范围内呈线性关系,适用于测定矿石中小于0.2g/t的金。 相似文献
5.
在Clark-Lubs缓冲溶液(pH9.8)中,锰(Ⅱ)能催化过氧化氢氧化酸性铬蓝K的反应。据此,建立了测定痕量锰的分光光度新方法。方法灵敏度为1.49×10~(-6)μg/m~2。测定范围0～50ng/25ml。据Arrhenius方程式测得催化反应表观活化能为86.41KJ/mol。方法已用于硅酸盐单矿物中锰的测定,变异系数5.90％。 相似文献
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在pH=4.5的HAc-NaAc缓冲溶液介质中,以溴化十六烷基吡啶(CPB)为增敏剂,痕量Cu(Ⅱ)能催化过氧化氢氧化溴酚蓝使之褪色,据此用于测定痕量铜。讨论了介质、试剂用量、反应温度、反应时间、表面活性剂及其共存离子的影响,确定测定波长为593 nm及最佳实验条件,测得反应表观活化能为90.3kJ/mol。在优化条件下,方法检出限为0.646 ng/mL,Cu(Ⅱ)的质量浓度在0～0.064μg/mL范围内与lg(A0/A)呈良好的线性关系,大多数常见元素不干扰测定。方法用于煤样中痕量铜的分析,5次测定的相对标准偏差小于3.1%,加标回收率在92.7%～107.0%,测定结果与原子吸收光谱法的结果一致。 相似文献
7.
双硫腙(H2Dz)是一种常用的螯合萃取剂，多用于光度法测定金属离子。以H2Dz作还原剂建立的萃取催化动力学分析法已用于Cu(Ⅱ)，Cr(Ⅵ)，NO^-2等的测定。本文采用该法对铁矿、铝合金和土壤中的痕量铜进行测定，结果满意。该法具有灵敏度高，操作简便，试样用量少，中止指示反应简单等优点。 相似文献
8.
本文用作者合成的新试剂——钒金试剂Ⅱ为指示剂,该试剂在酸性溶液中被V(ν)氧化变为紫红色,灵敏度达5.13×10~(-15)gV(ν)/ml。试样经磷酸处理,在磷酸介质中用三氯化钛(或氯化亚锡)还原U(Ⅵ)呈U(Ⅳ),过量Ti(Ⅲ),Sn(Ⅱ)用亚硝酸钠氧化呈Ti(Ⅳ),Sn(Ⅳ),而U(Ⅳ)不被氧化。过量亚硝酸钠用脲素消除,在24％—26％磷酸酸度下,以2滴0.2％钒金试剂Ⅱ为指示剂,依据铀量用相应浓度钒酸铵标准溶液,滴定度T=0.003,0.01,0.03,0.1,0.3,1,3,10,30,100,300,1000,3000,10000,30000,100000,300000ngU/ml滴定U(Ⅳ)至溶液出现紫红色为终点。其他离子无干扰。测定天然水、海水、雨水中铀的范围为0.3—5000000ng/L;测定岩石、矿物中铀的范围为10—0.0000001％。0.005ng铀,5次重复测定的相对标准偏差为6.2％。铀的检测限为0.6pg/ml。 相似文献
9.
苯基荧光酮—CPB光度法测定铜 总被引：5，自引：1，他引：5
本文研究了在溴化十六烷基吡啶(CPB)存在下,苯基荧光酮(PF)与Cu的显色反应条件。结果表明:在pH5.4六次甲基四胺-HC1缓冲介质中,Cu(Ⅱ)与PF及CPB生成的三元配合物最大吸收波长在565nm,表观摩尔吸光系数为1.1×10~5L·mol~(-1)·cm~(-1),Cu量在0—3μg/25ml范围内符合比尔定律,方法可用于硫铁矿中x—0.00x%Cu的测定。 相似文献
10.
催化动力学分光光度法测定痕量铁 总被引：1，自引：0，他引：1
本文利用在稀HCl介质中,邻菲啰啉(phen)作活化剂的条件下Fe~(3+)催化H_2O_2氧化次甲基绿(MG)的褪色反应,建立了催化动力学光度法测定Fe。方法已用于水和铝合金分析,具有灵敏度高、选择性好等优点。 1 试验方法 在两支25ml比色管中,分别加入0.02mol/L HCl 3ml,5.0×10~(-4)mol/L MG 1.4ml,0.1％phen 1.0ml,向其中一支比色管中加0.5μg Fe~(3+),另一支作试剂空白,再分别加入3％H_2O_2,1.0ml. 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
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
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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