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211.
The ion elution process has a severe effects on the formation of ice core record, which is discussed on the results of ice core record from kangwure Glacier, Xixabangma Peak.  相似文献   
212.
The study on the competitive adsorption shows that the magnitude order of metal ions adsorbed onto oxide and silicate minerals in near-neutral solution with low ionic strength is in mole/nm2 as follows: CaCO3 > quarte > hydromuscovite > kaolinite > Ca-montmorillonite > goethite > gibbsite. These minerals can be divided into three groups according to their surface equilibrium constantsK M of the adsorption reactions, which are the function of the dielectric constants ε of the absorbent minerals. The relationships between constantsK M and mineral dielectric constants ε are described as follows: lgK M 1 = 7.813-26.15/ε lgK M 2 = 9.030-26.15/ε lgK M 3 =11.63-26.15/ε for the adsorption reaction: >SO- + Mn+≥SOMn-1)+ (n = 1, 2, 3) The first group of minerals include quartz, goethite, 1:1 phyllosilicates and other oxide minerals; the second: gibbsite, brucite and 2:1 phyllosilicates; the third: carbonate, sulphate and phosphorate minerals. The appearance reaction constants have a variation of magnitude ±0.5 for different metal ions with the same mineral. This project was financially supported by the National Natural Science Foundation of China (No. 49572091).  相似文献   
213.
吴健 《地球物理学报》1997,40(6):739-746
以弛豫碰撞模式下Boltzmann方程的解为基础,从极光区视线方向上离子的非Maxwell一维速度分布函数的Raman等人的积分解出发,导出了一维速度分布函数的解析形式解,给出了它的一些特性,并研究了该分布函数随电场增强而出现的饱和现象,给出了物理解释,计算了几种情况下的饱和电场值.  相似文献   
214.
萤石颜色与自由基关系的电子自族共振(ESR)研究   总被引:1,自引:0,他引:1  
萤石颜色与自由基关系的电子自族共振(ESR)研究唐荣炳,温桂兰(中国科学院地球化学研究所,贵阳550002)(中国科学院广州地球化学研究所,广州510640)关键词萤石,顺磁离子,自由基长期以来,对矿物颜色的研究,先是定性观察和分类,再是应用光的吸收...  相似文献   
215.
原煤尾气和煤渣中多环芳烃相关性测定   总被引:2,自引:0,他引:2  
张丽珠  刘永庆 《岩矿测试》1996,15(4):268-273
对原煤、尾气和煤渣中多环芳烃进行了相关性测试。在模拟工业锅炉代表性燃烧条件下将烟煤和无烟煤样品在管式炉中燃烧,分别采用GCMS和HPLC法对原煤、尾气和煤渣中的多环芳烃种类和含量进行了定性和定量测定。通过在特定条件下某一煤种中多环芳烃种类、含量在燃前、燃后变化的相关性,探索煤中多环芳烃在燃烧过程中的衍变规律  相似文献   
216.
与传统的离子色谱相比较,讨论了目前分析化学的前沿技术毛细管离子分析技术,它具有分析快速、高效、分离度好、样品预处理简单、用样量少、维护方便、自动化程度高等特点,完全可替代目前在分析极地冰雪中所通用的离子色谱仪,成为极地冰雪化学分析强有力的新的分析工具  相似文献   
217.
Collisionless shocks are well-known to be very efficient energizers of ions. At the first step of energization relatively low energy suprathermal ion distributions are formed in the vicinity of the quasiperpendicular collisionless shock front during ion reflection and direct transmission. These distributions are formed promptly and at the scale of the shock width mainly due to the ion interaction with the quasistationary electromagnetic structure of the front itself. Their features are intimately related to the fine structure of the shock front in the sense that they depend not only on the bulk shock parameters, such as Mach number, but also on the details of the distribution of the fields, in particular, shock width. Therefore, studies of these distributions may provide valuable information about the shock structure itself. We review the observational data collected during in situ measurements (mainly at the Earth bow shock) and compare it to the numerical simulations and theoretical developments. The developed theory of the ion dynamics in the stationary shock front relates the ion reflection and heating to the insufficient deceleration of the ions in the ramp by the cross-shock potential, as compared to the expected downstream drift velocity, required by the Rankine-Hugoniot relations. As a result, the direct flow energy it transferred into the gyration energy, leading to the gyration of the ion distribution as a whole and enhanced spread in the velocity space, that is, effective collisionless heating. Anisotropy and nongyrotropy are typical features of ion distributions at both low and high-Mach number shocks, which is confirmed by observations. Time-dependent fields, which are not considered in the stationary shock model, are thought to provide subsequent smoothing and isotropization of the ion distributions. These processes occur at scales substantially larger than the shock width.  相似文献   
218.
海泡石是一种层链状硅酸盐,是含水富镁的粘土矿物。该区海泡石矿层厚度一股为2~3厘米,海泡石的单个纤维长一般为几厘米,有的长达十几厘米。笔者对海泡石作了差热、X射线衍射、红外光谱、扫描电镜和化学全分析。它的化学成分为:SiO_2 56.16%,MgO 22.61%,H_2O±17.88%。海泡石是由白云质大理岩经构造破碎、分解使镁离子集中沉淀形成的。海泡石的用途较广,可以作为离子交换剂、吸附剂、催化剂、地热和深部石油钻井中的泥浆原料等。  相似文献   
219.
McMurdo dry valleys of Antarctica represent the largest of the ice-free areas on the Antarctic continent, containing glaciers, meltwater streams, and closed basin lakes. Previous geochemical studies of dry valley streams and lakes have addressed chemical weathering reactions of hyporheic substrate and geochemical evolution of dry valley surface waters. We examine cation transport and exchange reactions during a stream tracer experiment in a dry valley glacial meltwater stream. The injection solution was composed of dissolved Li+, Na+, K+, and Cl-. Chloride behaved conservatively in this stream, but Li+, Na+, and K+ were reactive to varying degrees. Mass balance analysis indicates that relative to Cl-, Li+ and K+ were taken up in downstream transport and Na+ was released. Simulations of conservative and reactive (first-order uptake or generation) solute transport were made with the OTIS (one-dimensional solute transport with inflow and storage) model. Among the four experimental reaches of Green Creek, solute transport simulations reveal that Li+ was removed from stream water in all four reaches, K+ was released in two reaches, taken up in one reach, and Na+ was released in all four reaches. Hyporheic sediments appear to be variable with uptake of Li+ in two reaches, uptake of K+ in one reach, release of K+ in two reaches, and uptake of Na+ in one reach. Mass balances of the conservative and reactive simulations show that from 1.05 to 2.19 moles of Li+ was adsorbed per reach, but less than 0.3 moles of K+ and less than 0.9 moles of Na+ were released per reach. This suggests that either (1) exchange of another ion which was not analyzed in this experiment or (2) that both ion exchange and sorption control inorganic solute transport. The elevated cation concentrations introduced during the experiment are typical of initial flows in each flow season, which flush accumulated dry salts from the streambed. We propose that the bed sediments (which compose the hyporheic zone) modulate the flushing of these salts during initial flows each season, due to ion exchange and sorption reactions.  相似文献   
220.
利用13X沸石分子筛净化含Pb~(2+)废水的实验研究   总被引:11,自引:0,他引:11  
马鸿文  肖万  陶红 《现代地质》2003,17(2):157-162
采用静态间歇法 ,实验研究了含Pb2 +废水的 pH值及吸附时间对 13X沸石分子筛吸附Pb2 +性能的影响 ,得出了最佳去除效果的优化条件为 :废水的 pH值接近中性 ,吸附时间 10min。通过吸附实验 ,确定了在Pb2 +初始浓度为 2 0mg/L的条件下 ,13X沸石对Pb2 +的吸附量为 2 1 4 2mg/g ,即每克沸石净化含Pb2 +废水的最大体积量约为 75 0mL。解析实验表明 ,加入沉淀剂 ,浓缩洗脱液中的Pb2 +即以PbS的形式生成沉淀 ,为回收金属铅提供了可能 ;13X沸石在循环使用 5次的条件下 ,对废水中Pb2 +的吸附率仍高达 98% ,重复使用性能良好。经处理后的净化水中Pb2 +的浓度小于 0 4mg/L ,显著低于国家废水排放标准GB8978 88的指标 ( 1 0mg/L)。 13X沸石对Pb2 +的主要吸附形式是离子交换和表面络合反应。  相似文献   
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