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1.
麦饭石在腐殖酸及重金属离子的吸附作用   总被引:2,自引:0,他引:2  
研究了麦饭石对腐殖酸和重金属离子(Hg^2+,Pb^2+,Cu^2+,Zn^2+,Cd^2+)的吸附作用,实验结果表明麦饭石对腐殖酸和重金属离子都具有较好的吸附性能,且腐殖酸的存在有利于麦饭石对重金属离子的吸附,pH值是影响吸附的重要因素,当pH值5.0~6.0时,麦饭石同时吸附腐殖酸和重金属离子的效果最好,麦饭石在吸附腐殖酸和重金属离子的同时能溶出微量元素硒,这对于大骨节病的防治有得要意义。  相似文献   

2.
重金属离子与石英表面反应的实验研究   总被引:18,自引:3,他引:15  
吴宏海  吴大清 《地球化学》1998,27(6):521-531
石英对Cu^2+,Pb62+,Zn^2+,Cd^2+,和Ni62+等二价重金属离子的吸附等温线研究表明,石英对重金属离子的吸附反应可用Freudlich方程很好地进行描述,拟合曲线相关系数〉0.96,吸附反应以形成金属离子单配位形态为主,只是Cu^2+,Zn^2+和Ni^2+等三种离子有一部分双配位形态生成。同时,利用表面配位理论模式对实验结果进行拟合,其结果为表观表面配位常数lgKM=2.2-3  相似文献   

3.
蒙脱石等粘土矿物对重金属离子吸附选择性的实验研究   总被引:71,自引:6,他引:65  
矿物质与重金属离子间的相互作用已是当今环境科学、矿物学,土壤化学等学科领域研究的热点。通过蒙脱石,伊利石和高龄石在一定的介质条件下对Cu^2+、Pb^2+、Zn^2+、Cd^2+、Cr^3+五种重金属离子的竞争吸附实验研究,阐明了三种粘土矿物对五种重金属离子的吸附选择性。  相似文献   

4.
天然沸石对Pb(Ⅱ)和Ni(Ⅱ)离子的吸附作用研究   总被引:18,自引:0,他引:18  
在静态条件下,研究了沸石对重金属离子(如Pb^2+和Ni^2+)的吸附与交换。结果表明,沸石对重金属离子具有较强的吸附性能,pH值的影响吸附的主要因素,离子交换和表面络合反应是主要吸附形式。  相似文献   

5.
重金属离子与方解石表面反应的实验研究   总被引:15,自引:3,他引:12  
本文对重金属离子与方解石表面反应作了系统研究。方解石表面对重金属离子的吸附等温线可分为4种类型:A型,Langmuir型;B型,Frendich型;C型,吸附-沉淀突变型;D型,吸着线性型。实验研究表明,方解石表面反应多种模式并存。Cu^2+、Zn^2+、Cd^2+和Ni^2+在低浓度时表面为离子交换吸附。较高浓度时表现为交换和表面配位吸附并存,而高浓度时则表现为表面沉淀;Ag^+Pb^2+、Cr  相似文献   

6.
溶液介质条件对重金属离子与石英表面反应的影响   总被引:12,自引:2,他引:10  
实验研究表明,随着溶液PH值的升高石芟夺Cu^2+、Pb^2_、Cd^2+等重金属离子的吸附量和表面吸附覆盖率逐渐增大,而表面反应产物的结合开矿相应地出现由单核化合物、多核化合物〖SOCu4(OH)3^4+〗,直至表面沉淀(SOH…Cu(OH)2(s)〗。随着温度升高,石英对Cu^2+、Pb^2+、Cd^2+等重金属离子的吸附量逐渐减是随着溶液离子强度的增大,石英对Cu^2+离子的吸附量和表面离了  相似文献   

7.
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   

8.
硫化物吸附金属离子的实验研究──Ⅰ类型   总被引:1,自引:0,他引:1  
合成PbS、ZnS对金属离子Ag+、Cu(2+)、Cd(2+)、Zn(2+)、Fe(2+)、Mn(2+)、Mg(2+)、Sb(3+)和Bi(3+)的吸附等温线(50℃)研究表明,其可分为A、B、C三类:A类,线性型,即吸附量随吸附离子浓度增加而呈线性上升,并表现出百分之百吸附,属于此类的吸附有PbS对Ag+、Cu(2+)离子吸附和ZnS对Ag+、Cu(2+)、Cd(2+)离子的吸附;B类,朗谬尔型,即随吸附离子的浓度增加,吸附量逐趋向一饱和值,属于此类的有PbS对Fe(2+)、Sb(3+)、Bi(3+)等离子及ZnS对Fe(2+)、Mn(2+)、Mg(2+)等离子的吸附;C类,反朗谬尔型,即吸附量随吸附离子浓度增加而呈非线性增加。属此类吸附的有PbS对Zn(2+)、Cd(2+)等离子的吸附。合成PbS、ZnS对金属离子的吸附量与天然方铅矿和闪锌矿中微量元素含量可类比,这意味着吸附作用可能在硫化物矿物微量元素形成过程中起着重要的作用。  相似文献   

9.
淡—咸水界面切换中矿物表面吸附性变化研究   总被引:7,自引:3,他引:4  
吴大清  彭金莲 《地球化学》1999,28(2):155-162
实验研究表明,当电解质离子浓度从有低上升到极高时,矿物吸附金属离子的普遍下降,例外的仅有石英、水云母、CaCO3和三水铝矿对Pb^3+、Zn^3+离子的吸 云母对Cu^2+的吸附和石英对Cr^3+的吸附。理论研究表明,一方面,电解质NaCl的加入,使矿物表面Sten的层电位发生变化,△ψ(ψ0-ψβ)的绝对值增大,提高了矿物表面吸附离子的能力;另一方面,由于Na离子的竞争吸附和Cl离子与深液中金  相似文献   

10.
风化壳淋积型稀土矿床成矿机理的实验研究   总被引:10,自引:2,他引:10  
林传仙  郑作平 《地球化学》1994,23(2):189-198
风化壳淋积型稀土矿床是很重要的一种矿床类型。作用采用水析法提取了梧州市区风化壳淋积型稀土矿床中的粘土矿物,并进行了钕和镱的吸附实验研究。实验结果表明,在不同的实验体系中,吸附反应达到平衡的时间是不同的,2%HC1至少12h,1%HC1至少0.1h。影响粘土吸附稀土的物理化学因素有:溶液浓度,溶液酸碱度(pH值),离子强度,固液比和温度等。在pH值较低的相同实验条件下,轻稀土的吸附效率要明显高于重稀  相似文献   

11.
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.
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.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
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.
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.
16.
PALEONTOLOGY     
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   

17.
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   

18.
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   

19.
PETROLOGY     
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   

20.
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   

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