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1.
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   

2.
硫化物吸附金属离子的实验研究:——Ⅱ类型   总被引:6,自引:0,他引:6  
吴大清  彭金莲 《地球化学》1996,25(2):181-189
合成PbS、ZnS对金属离子Ag^+、Cu^2+、Cd^2+、Zn^2+、Fe^2+、Mn^2+、Mg^2+、Sb^2+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  相似文献   

3.
吴大清  彭金莲 《地球化学》1996,25(3):242-250
合成PbS和ZnS对Ag^+、Cu^2+、Cd^2+、Fe^2+、Mn^2+、Mg^2+、Sb^2+和Bi^3+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Bi^3+离子的吸附,其吸附量随  相似文献   

4.
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   

5.
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   

6.
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   

7.
东坪金矿床的围岩蚀变和流体特征   总被引:1,自引:0,他引:1  
东坪金矿床围岩蚀变特征、流体包裹体特征与氢氧同位素特征研究表明,成矿流体富集K^+,Na^+,Au^+,Cl^-和CO2、H2S成矿溶液以岩浆热液为主,但有天水的混合。金在溶液中以Au(HS)^-2和AuCl^-2形式存在,构造活动引起的压力突变和流岩反应是引起金沉淀的主要因素。  相似文献   

8.
沉积CaCO3与金属离子界面反应动力学研究   总被引:12,自引:2,他引:10  
金属离子与沉积碳酸盐之间2同反应动力学模拟实验表明,由于CaCO3快速溶解和溶液PH急剧上升,大部分Pb^2+、Zn^2+离子与溶液中CO3^2-和OH^-离子反应生成白铅矿PbCO3、水白铅矿Pb3(OH)2(CO3)2,或Zn(OH)3和锌矿Zn(OH)6(CO3)2沉淀于体相溶液中,仅有少部分Pb^2+、Zn^2+通过扩散与CaCO3表面发生离子交换反应。25℃时,Pb^2+溶液中以白铅矿沉  相似文献   

9.
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   

10.
刘再华 Dreyb.  W 《地质学报》1998,72(4):340-348
利用旋转盘实验装置和高分子生物催化剂技术,笔者研究了流动CO2-H2O系统中方解石溶解动力学及其控制机制。实验发现,方解石的溶解既受到固-液界面间扩散边界层(DBL)的控制,还受到扩散边界层内CO2慢速转换反应(CO2+H2O←→H^++HCO^)的控制。然而,高CO2分压(Pco2〉0.01atm)时,溶解主要为CO2慢速转换控制,而低CO2分压(Pco2〈0.01atm)时,溶解主要为扩散为边  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.
15.
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   

16.
正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.)  相似文献   

17.
正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology,  相似文献   

18.
正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.)  相似文献   

19.
正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se-  相似文献   

20.
正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with  相似文献   

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