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561.
Based on the mineral and chemical compositions of spoils taken from the Shilu Cu-Mo deposit and Hetai gold deposit ,the leaching and batch experiments were made on spoils taken from these two deposits using the leaching column designed by the authors.The experimental results showed that it is not always true that the imine drainage is acidic.Its acidity depends on acid-buffering capacity of gangue,host rock and its alteration mineral assemblage.The composi-tion of the drainage water is related with the interaction between superficial or underground water and solid materials in the spoils,including minerals,hydroxides and amorphous substances.The leaching extent of the element is related with its occurrence form in the deposit.The prefer-ential flow results in leaching-out of heavy metals in large amounts.So it is important to prevent the generating of preferential flow in the system.The results will provide very important grounds for the comprehensive management of land and ecological rehabilitation of the mine site.  相似文献   
562.
563.
The concentrations (per cent) of secondary clay minerals (mica, vermiculite, montmorillonite, chlorite and kaolinite) in the A-horizon of 99 soil sample sites were entered into a cluster program to determine the common clay mineral assemblages found in U.S. soils. Five major assemblages were identified with the most common assemblage consisting of mica, montmorillonite and kaolinite. A suite of climatic variables was determined for each of the 99 sites, including the water balance variables and Arkley's leaching index. A discriminant analysis was then used to predict the occurrence of a clay assemblage from the climate data. Sixty per cent of the sites could be correctly predicted, although not all assemblages could be predicted equally well; two assemblages could be predicted with 88 and 82 per cent accuracy. The precipitation of the wettest month and Arkley's leaching index accounted for most of the predictive power. Thus this study supports theoretical models which suggest that seasonal moisture supply is an important control of clay genesis and persistence. A residuals analysis indicated that many of the palaeosols in the data set and many of the soils from glacial parent materials possessed clay mineral assemblages not expected on the basis of modern climate.  相似文献   
564.
13C/12C- and 18O/16O-signatures of Calcite Precipitations in Drainage Systems Measurements of drainage waters show two distinct processes of calcite precipitation: 1. reprecipitation of calcium carbonate previously dissolved in groundwaters and 2. absorption of atmospheric CO2 by alkaline solutions. Both processes may be distinguished by the stable isotopes of oxygen and carbon. Calcite precipitated from carbonate groundwater yields δ13C ≈ ?13%0 (PDB) and δ18O ≈ 24%0 (SMOW), whereas calcite produced by CO2-absorption shows δ13C ≈ ?25%0 (PDB) and δ18O ≈ 10%0 (SMOW).  相似文献   
565.
煤系高岭岩制取氯化铝和水玻璃实验   总被引:4,自引:1,他引:4  
薛茹君  朱克亮 《矿物学报》2001,21(2):169-173
本文讨论煤系高岭岩综合制取氯化铝和水玻璃的工艺路线及工艺条件,采用适当的酸浸工艺可使高岭岩的铝浸出率提高到接近100%,使酸渣中的SiO2含量提高到95%左右,其他杂质含量大大降低,为活性硅渣的利用提供保证,采用湿法工艺,加入适当助剂,可在缓和的反应条件下,使硅的转化率达到95%以上,制得合格的水玻璃产品。  相似文献   
566.
煤矸石中潜在有害微量元素淋溶析出研究   总被引:21,自引:0,他引:21  
在煤矸石淋溶实验的基础上,研究了有害微量元素从煤矸石中淋溶析出的浓度与其在煤矸石中的含量和赋存状态的关系。结果表明,溶出浓度受淋溶时间,淋溶液温度,酸碱度的影响。淋溶液温度越高,淋溶时间越长,则有害微量元素从煤矸石中析出的浓度越高;不同的有害微量元素受淋溶液pH值大小影响程度也不相同。  相似文献   
567.
木文着重介绍了双王金矿床低品位金矿石堆浸概况、工艺流程、技术经济指标及与国内比较,指出了双王金矿床堆浸特点和取得的初步认识,探讨了在一般条件下双王金矿床堆浸临界经济品位及今后堆浸远景。  相似文献   
568.
Experiments were conducted on the leaching of gold from greenstone by chloride solution under the temperature of 200—550℃ and the pressure of 60 MPa. During part of the experiments, the oxygen fugacity was controlled. The results show that the leaching rate of gold is related to temperature, composition of the solution, pH and oxygen fugacity. In the experiment with oxidative acidic solution, the leaching rate was up to 50% or more. It is known that the leaching of gold is restricted by the reaction in which the gold is dissolved from the rock to form gold chloride complex. Therefore, the authors hold that the acidic chloride solution derived from granite magma has caused the remobilization-migration of gold from greenstone and its enrichment into ore.  相似文献   
569.
以华贵栉孔扇贝Chlamys nobilis(Reeve)为材料,获得聚丙烯酰胺凝胶电泳为单一蛋白区带的酶制剂。用凝胶过滤法测得该酶的分子量为159000,由20种氨基酸组成,共1118个氨基酸残基。每个酶蛋白含有4个Zn原子。将该酶的酶制剂制成脱Zn酶后,与相同浓度过度性两价金属离子作用,其活力回升以Zn最强,Co次之。若向脱Zn酶蛋白分别加入一定量Zn原子或Co原子,根据实验结果初步推测:每个酶蛋白的4个Zn原子中有2个Zn原子先与该酶结合,与酶的催化作用有密切关系;另外2个Zn原子与酶结合,则起维持酶结构的作用,与哺乳动物和Eschericha coli来源的碱性磷酸酶研究结果一致。此外,本实验采用可见吸收光谱和圆二色谱(CD)来确证Co能很好地取代该酶蛋白内的Zn,与Simpon报道相比较,得知当Co原子加入脱Zn酶时,先加2个Co~(2 )离子结合到该酶的结构部位,而后加2个Co~(2 )离子才结合到催化部位。  相似文献   
570.
海洋沉积物中碱性磷酸酶活力与水体污染的关系   总被引:4,自引:0,他引:4  
薛雄志  洪华生 《台湾海峡》1995,14(3):274-279
厦门西港和香港维多利亚港近岸沉积物中碱笥磷酸酶活力与水体受污染程度的多项指标均表现出一定的相关性,如水体不BOD5、无机氮、COD、无机磷等的含量及采样点离陆源排放点的距离等相关性较大,其相关性在水动力条件差的水域尤为显著。  相似文献   
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