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61.
2种黏土矿物对磺胺嘧啶的吸附 总被引:2,自引:0,他引:2
选择蒙脱土和高岭土2种典型黏土矿物为吸附体, 通过静态吸附试验研究其对磺胺嘧啶的吸附行为,考察温度和pH值对磺胺嘧啶吸附的影响.结果表明,2种黏土矿物对磺胺嘧啶的吸附等温线均能较好地符合Freundlich和Langmuir吸附方程,且Langmuir方程拟合效果优于Freundlich方程;高岭土对磺胺嘧啶的吸附量大于蒙脱土;温度升高和pH值过高或过低均不利于磺胺嘧啶的吸附. 相似文献
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用X-射线衍射分析技术和化学方法研究不同农业利用方式对湘南第四纪红粘土及其发育土壤的粘粒矿物学组成和表面电荷特性的影响.结果表明:湘南第四纪红壤的粘粒矿物组成以高岭石为主,其次是1.4nm过渡矿物.经过人为耕种尤其在水田条件下,蛭石和水云母的含量增加,铁的活化度增大.土壤表面电荷数量(CECpH3.2、CECp、CECv、AEC)和电荷零点(pH)的值也发生相应的改变. 相似文献
65.
稻田土壤对铵的矿物固定对土壤保氮作用的贡献 总被引:3,自引:0,他引:3
为了定量评价土壤对铵的矿物固定作用在土壤对肥料氮的保持作用中的相对贡献,通过室内培养试验和分析测定,研究了湖南省几种主要母质发育的水稻土对添加铵的矿物固定作用及其对土壤保氮作用的贡献。结果表明:土壤对外源铵的矿物固定是土壤重要的保氮机制之一,但不同土壤对保氮作用的相对贡献大小不一,以河沙泥的固铵作用对土壤保氮作用的贡献最大,固铵量占总保氮量的51.5%,红黄泥最低,固铵量仅占总保氮量的17.1%,其余五种土壤的固铵作用对土壤保氮作用的贡献大小顺序依次是黄泥田(43.7%)、湖潮泥(35.5%)、紫泥田(35.4%)、灰泥田(25.0%)、麻沙泥(20.8%)。 相似文献
66.
Enrichment of potentially toxic elements in areas underlain by black shales and slates in Korea 总被引:6,自引:0,他引:6
Jin-Soo Lee Hyo-Taek Chon Jong-Shin Kim Kyoung-Woong Kim Hi-Soo Moon 《Environmental geochemistry and health》1998,20(3):135-147
The Okchon black shale in Korea provides an important example of natural geological materials containing toxic elements; the Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won and Chu-Bu areas are underlain by these black shales and slates of the Guryongsan Formation. This formation is part of the Okchon Group which is found in the central part of Korea. Geochemical surveys were undertaken in these five study areas in the Okchon Zone in order to examine the level of enrichment and dispersion patterns of potentially toxic elements in rocks and soils. After appropriate preparation, samples were analysed by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectrometry for a range of elements. Arsenic, Cu, Mo, V, U and Zn are highly enriched in the Okchon black shales and their mean concentrations are significantly higher than those in black slates. These elements are closely associated with one another from a geochemical viewpoint and may be enriched simultaneously. Mean concentrations of As, Mo and U in soils derived from black shales occurring in the Duk-Pyung and Chu-Bu areas are higher than the permissible level suggested by Kloke (1979), and the enrichment index decreases in the order of Duk- Pyung > Chu-Bu > Chung-Joo > Geum-Kwan = I-Won areas. Uranium-bearing minerals such as uraninite and brannerite have been identified in black shales from the Chung-Joo area by electron probe micro-analysis. Uraninite grains are closely associated with monazite and pyrite with a grain size ranging from 2m to 10m whereas brannerite grains occur as a euhedral form 50m in diameter. 相似文献
67.
This study investigated geochemical characteristics of the acid mine drainage (AMD) discharged from the abandoned mine adits in the vicinity of the Dogye coal mine in Korea. Acid mine drainage discharged from Jeoncha pit adit of the Dogye coal mine, which is the main source of the AMD in the study area, had a pH value of 3.0 and concentrations of 2148mg SO4
2– L–1, 229mg Fe L–1, 71mg A1 L–1 and 11mg Mn L–1. The reduction of some metal concentrations downstream from the discharge point could be explained on the basis of dilution and precipitation. The order of removal of metal ions downstream from the discharge point was Fe>A1, Cu>Zn, Mn. Acidity could be used as a good determining factor offering comprehensive and quantitative values for the polluting extent of acid mine drainage. The acidities existing in all acidic water samples in the Gunahan district originated primarily from mineral acidity, especially in the upper Nahan Creek from dissolved Fe and Al and in the middle and down Nahan Creek from dissolved Al. From the application of the WATEQ4F program, it was determined that predominant species of dissolved Fe in all water samples was Fe2+, and those of dissolved Al were AlSO4
+ and Al3+ except for IW2 sample which was associated with white precipitates. The species of dissolved Al in IW2 sample include also AlOH2+ and Al(OH)2
+. The saturation indices of goethite and haematite were positive in the water samples associated with ochrous precipitates (usually called Yellow Boy), therefore these solids might be precipitated. For the IW2 sample, the saturation indices of amorphous Al(OH)3 and gibbsite were positive, so theoretically these solids might also be precipitated. By XRD analysis, it was found that goethite occurs in ochrous precipitates, and gibbsite in white precipitates. 相似文献
68.
介绍了近年来华东地区资源调查评价的新成果。表明本地区仍具有较大的找矿潜力。并提出了华东地区下一阶段矿产资源调查工作的建议。建议分区域矿产调查、预查、普查三个工作层次。重点在武夷山铜铅锌成矿带、赣南钨多金属成矿区和皖赣相邻地区铜多金属成矿区(一带两区)。侧重铜、锡、钨、富铅锌等。 相似文献
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对土壤中常见的三种粘土矿物对Pb2+的吸附作用及其主要影响因素进行了探讨。结果表明,三种粘土矿物对Pb2+的吸附能力顺序为:蒙脱石>伊利石>高岭石。蒙脱石对Pb2+的吸附受pH的强烈影响,pH高有利于对Pb2+的吸附。与蒙脱石形成复合体形式的有机化合物的存在不利于蒙脱石对Pb2+的吸附。 相似文献