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在熔融的２ＰｂＯ．Ｂ２Ｏ３中（９７４Ｋ）,用滴溶量热法测定了２９８Ｋ下由组分Ｋ２ＣＯ３和ＣａＣＯ３形成的复碳酸盐Ｋ２Ｃａ（ＣＯ３）２（它有胶方解石和碳钾钙石两种多型）和Ｋ２Ｃａ２（ＣＯ３）３为－７．２±５．８ｋＪ／ｍｏｌ。同时推算出了复碳酸盐生砀熵变ΔＳｔ。假定具有序结构的胶方解石的ΔＳｔ＝０,则碳钾钙石的生成熵为４０．９±５．１Ｊ／ｍｏｌ．Ｋ,Ｋ２Ｃａ２（ＣＯ３）３为３９．４±７．３Ｊ／ｍｏｌ． 相似文献
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合成ＰｂＳ和ＺｎＳ对Ａｇ２＋、Ｃｕ２＋、Ｃｄ２＋、Ｆｅ２＋、Ｍｎ２＋、Ｍｇ２＋、Ｓｂ２＋和Ｂｉ３＋等离子吸附量与温度关系的实验研究表明，其遵从Ｋｅｌｖｉｎ公式：在Ａ类吸附，即抗衡离子交换型吸附中，温度上升，其吸附量升降由反应热决定，本实验中Ａ类吸附多为上升型；而大部分Ｂ和Ｃ类吸附，即朗谬尔型及反朗谬尔型的吸附量则随温度上升呈指数下降。例外的仅有ＰｂＳ对Ｂｉ３＋离子的吸附，其吸附量随温度上升有微弱的上升。这可能与Ｂｉ３＋离子和吸附剂ＰｂＳ之间共晶反应和铅的铋硫盐的形成有关。Ａ类吸附的吸附量受介质条件变化影响很少。但对Ｂ和Ｃ类吸附，吸附量受ｐＨ和离子强度变化影响取决于三个因素：①吸附剂ＰｂＳ、ＺｎＳ表面电荷特性；②溶液介质条件变化时吸附离子在溶液中离子态的分布与变化；③被吸附离子在吸附剂中扩散和形成化合物或共晶的能力。因此，当ｐＨ增加时，Ｐｂｓ和ＺｎＳ对金属离子吸附量的变化表现出多样性：增加的有ＰｂＳ对Ｆｅ２＋离子的吸附；下降的有ＰｂＳ对Ｓｂ３＋离子的吸附和ＺｎＳ对Ｆｅ２＋、Ｍｎ２＋离子的吸附；不变的有ＰｂＳ对Ｂｉ３＋、Ｚｎ２＋离子的吸附和ＺｎＳ对Ｍｇ２＋离子的吸附。当溶液中离子强度增加时，由于溶液中自由态离子 相似文献
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新显色剂2—（2—咪唑偶氮）—苯甲酸的合成及其与钴的显色反应研究 总被引：15，自引：0，他引：15
合成了新显色剂２（２咪唑偶氮）苯甲酸（简称ＩＡＢＡ）,分子式Ｃ１０Ｈ８Ｎ４Ｏ２,分子量２１６．２０,熔点２１３℃,各级酸离解常数ｐＫａ１为３．２,ｐＫａ２为９．８,研究了它的性质及其与钴显色反应的条件。在ｐＨ７的ＮＨ４Ａｃ介质中,试剂与钴形成紫红色络合物,λｍａｘ为５４６ｎｍ,试剂的λｍａｘ为４６２ｎｍ,Δλ为８４ｎｍ,Ｃｏ２＋与试剂络合比为１∶２,摩尔吸光系数１．６１×１０４Ｌ·ｍｏｌ－１·ｃｍ－１,Ｃｏ２＋在０～０．８ｍｇ／Ｌ遵守比尔定律。所拟方法直接测定了工业废水及ＶＢ１２中痕量钴,结果与原子吸收法相符,加标回收率为１０１．３％～１０２．２％,ＲＳＤ（ｎ＝６）在２．０％～２．７％。 相似文献
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铜（II）在高岭石表面的吸附 总被引：12，自引：2，他引：10
在天然天体系中,铜、铅、镉等重金属元素的形态分布、归宿和生物有放性强烈取决于重金属元素在水体颗粒物表面的分配趋势,本文对铜（ＩＩ）在常见的重要粘土矿物－高岭石表面的吸附进行了实难和模式研究,结果表明,在同时考虑自由水合离子Ｃｕ＾２＋和羟基金属郭子ＣｕＯＨ＾＋与高岭石表面络合的情况下,单一表面基团、无静电表面络合模式能很好地描述酮（ＩＩ）的吸附行为。拟合得到的ＣｕＯＨ＾＋的络合常数比Ｃｕ＾２＋的大得 相似文献
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粤东塌山含锡花岗斑岩原生铝质矿物特征和成因 总被引：1，自引：1，他引：1
粤东塌山含锡花岗斑岩以岩脉产出，侵位年龄１３８Ｍａ，含不等数量的原生铝质矿物，如红柱石、铁铝榴石、铁叶云母和白云母等。根据产出特征，红柱石被区分为两个世代，石榴子石分为三个结晶时期。结合全岩为过铝质（Ａ／ＮＫＣ＝１．２３４），高的Ｋ２Ｏ／Ｎａ２Ｏ（２．１５）、Ｒｂ／Ｓｒ（３．１０）、Ｋ／Ｒｂ（２１５）比和ＩＳｒ值（０．７１３１），低的εＮｄ（Ｔ）值（－７．４）和长石铅同位素组成相似于造山带铅演化模 相似文献
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铜(Ⅱ)在高岭石表面的吸附 总被引：7，自引：1，他引：6
在天然水体系中,铜、铅、镉等重金属元素的形态分布、迁移、归宿和生物有效性强烈取决于重金属元素在水体颗粒物表面的分配趋势.本文对铜(Ⅱ)在常见的重要粘土矿物--高岭石表面的吸附进行了实验和模式研究,结果表明,在同时考虑自由水合离子CU2+和羟基金属离子CuOH+与高岭石表面络合的情况下,单一表面基团、无静电表面络合模式能很好地描述铜(Ⅱ)的吸附行为.拟合得到的CuoH+的络合常数比Cu2+的大得多. 铜(Ⅱ)在高岭石表面的吸附量随pH值的升高而增加.吸附铜的两种表面化合态,>SOCu+和>SOCuOH的浓度在实验的pH范围内,也随pH值升高而增加,并且以>SOCu+为主. 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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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