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麦饭石中元素溶出的微结构模型探讨 总被引:6,自引:0,他引:6
进行了麦饭石中元素的溶出试验,结合麦饭石的矿物组成和岩石结构,探讨了麦饭石中矿物元素溶出的微结构模型,采用该微结构模型分析了颗粒尺寸、温度、时间及溶出次数对矿物元素溶出过程的影响。研究结果表明:麦饭石颗粒变小,溶出液的矿化度呈指数形式增加;麦饭石溶出次数增加,矿化度明显降低;溶出温度增加,矿化度和Sr含量增加,且增幅较大;溶出时间增加,矿化度和Sr含量增加,但增幅较小;麦饭石的矿物组成及岩石结构特征有利于矿物元素的溶出。麦饭石矿物元素溶出微结构模型可以表示为麦饭石浸入水中→界面水膜层形成→水渗入→水合作用→元素离子化→离子迁移、扩散→元素溶出,该模型进一步说明麦饭石粒度变小和溶出温度增加等都能促进矿物元素的溶出。 相似文献
195.
Sun Jingshi Zhu Yiming
Research Professor Tianjin Research Institute of Water Transport Engineering Tianjin
Associate Professor Dalian Aquatic Product Institute Dalian 《中国海洋工程》1995,(1)
Through hydraulic model experiment and site investigation, this paper has derived a calculation formula of dry-laid stone armour layer thickness of rubble mound breakwaters for fishery harbours. The influences of the friction force between stone blocks and the variations of wave length or period and water depth are considered in the formula. The calculated results of several existing structures are in good agreement with field data. This formula is more practical than those ever published both at home and abroad, and has been adoptted by the technical standards of aquatic projects published by the Ministry of Agriculture of China. It is applicable for the calculation of dry-laid stone armour layer of breakwater for small- or medium-size harbours. 相似文献
196.
Giuseppe Montana Luciana Randazzo Ilaria A. Oddo Mariano Valenza 《Environmental Geology》2008,56(2):367-380
Chemical, mineralogical and isotopic composition (34S/32S) analyses were carried out on “black crusts” developed on the old buildings of Palermo (Sicily) with the aim to distinguish
between natural and anthropogenic sulphur sources. Furthermore individual samples of total suspended particulate (TSP) were
collected and analysed in order to estimate the influence of air pollution on the decay process of calcareous stones in a
typical southern Mediterranean coastal environment. SEM/EDS analysis, X-ray diffractometry, IR spectroscopy and liquid chromatography
led to the compositional characterization of “black crusts” and airborne particulate matter in the city. Sulphur isotopic
compositions of gypsum-bearing crusts showed a prevailing contribution of anthropogenic sources (vehicle exhaust and other
combustion processes). Natural sulphur and/or sulphate sources (biogenic and/or sea-spray) were shown to play a secondary
role. These data can be considered a starting point for the determination of the rate of growth of “black crusts” in a coastal
Mediterranean urban environment like Palermo. In the future, they might be useful to local authorities for planning more efficient
maintenance action in order to slow as much as possible the rate of decay of the monumental heritage of the city. 相似文献
197.
介绍了CFG桩在人工填土地基处理中的应用情况,并对工程实践中的技术问题进行了分析和探讨。 相似文献
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The Söndrum stone quarry (Halmstad, SW Sweden) exposes a transition from migmatized granitic gneissic country rock into a foliated clinopyroxene‐free granitic gneiss, and then a central pegmatoid dyke dominated by clinopyroxene megacrysts. This transition zone represents a fracture‐controlled, fluid‐alteration zone that developed under conditions of 650–700 °C and 790 MPa. Mineral chemical trends in F, Cl, Fe, Ti, Mn and Y are interpreted as documenting a fluid infiltration event associated with the formation of the pegmatoid dyke. Fluid inclusions from the pegmatoid dyke are CO2 dominant, whereas in the surrounding country rock they are dominated by H2O‐NaCl‐CaCl2. Fluid inclusions from the intermediate foliated clinopyroxene‐free granitic gneiss are a mixture of the two types. The pegmatoid dyke appears to have originated from a high Ca activity, Fe‐Mg enriched, fluid‐rich granitic melt with a CO2 component, which was emplaced along a tectonic fracture in a regionally migmatized granitic gneiss in the lower crust. This was accompanied by limited partial melting of the surrounding granitic gneiss. The Ca activity of the melt was high enough to allow for the formation of clinopyroxene megacrysts as opposed to orthopyroxene. H2O‐enriched fluids expelled from the crystallizing pegmatoid dyke, which retained the majority of the CO2 helping to stabilize the clinopyroxene. The expelled fluids coarsened and chemically affected the surrounding country rock resulting in trends in the mineral and fluid inclusion chemistry seen today in the foliated and regional granitic gneiss. 相似文献