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During the microthermometric measurement(cooling)of aqueous inclusions with multivolatile components,solid crystals of gas clathrates often occur with snow-flower-or soft-ice appearances.The structural formula of these solids is M·nH_2O(where n≥5.67).Many hydrocarbons,related compounds and their binary or multi-component mixtures may generate gas clathrates.This phenomenum is of fundamental importance to the study of inclusions with hydrocarbon aqueous solutions,because this is related to the determination of inclusion parameters and the computation of thermodynamic parameters. In the nature most aqueous inclusions contain not merely one volatile component but multi-volatile components.Therefore,the measurement of aqueous inclusions with multivolatile components is of universal significance and great importance.There have been many studies and available formula or figures about the computation of thermodynamic parameters for aqueous inclusions with one volatile component.Nevertheless,there are few studies concerning with muhivolatile components and it is very difficult to computate thermodynamic parameters for aqueous inclusions with these components. In this paper,hydrated coefficient K is introduced.K_i is the ratio of molar fraction of component i in the gas phase to that in the gas clathrate,or K_i=y_i/x_i.Because K is a function of temperatures and pressures,it can be used to evaluate the temperature-pressure conditions on the phase behavior with muhivolatile components. Based on the regression analysis of available experimental data,the authors have developed computational expression of hydrated coefficients in relation to temperature and pressure for most hydrocarbons and other volatile components,which is helpful to conveniently compute thermodynamic parameters on stability state for elathrates with volatile components.As aqueous inclusions with muhivolatile components are common in the nature,by the use of final melting temperatures of clathrates from mierothermometry and these formula,fluid density of gas phase with valotile components and bulk fluid density of inclusions can be accurately calculated. Furthermore,this method may provide foundations to determine the isochores of inclusions and to calculate trapping temperatures and pressures. Finally,detailed analyses for two computational examples about aqueous inclusions with muhivolatile components are presented. 相似文献
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以湖北省鄂州市庙岭镇的红黏土为研究对象,以化学选择溶解法结合淋溶作用为处理手段,将原状土样中的游离氧化铁按梯度去除,获得连二亚硫酸钠-柠檬酸钠-碳酸氢钠(DCB)溶液淋溶时间与除铁率的关系,并分析了不同淋溶时间对红黏土物理力学特性及微观孔隙结构的影响。试验结果表明,DCB溶液淋溶时间与除铁率相关性较强,除铁率与时间呈先快速增长后逐渐稳定的关系。由于游离氧化铁在土颗粒间主要起胶结作用,故淋溶时间对红黏土的物理力学特性有较大影响。随着淋溶时间的增长,黏粒与胶粒含量逐渐增大,耐热性小幅提升,无侧限抗压强度显著减小,且无侧限抗压强度变化整体趋势为前期急剧降低至后期趋于平稳。核磁共振、差热分析和电镜扫描的结果表明,随着淋溶时间的增大,庙岭红黏土内部孔隙增大,自由水减少,结合水增多,微观形态上团粒结构遭到破坏,胶结物质明显减少,结构形式从紧凑的粒团堆叠结构逐渐转化为聚集体-松散颗粒状结构。 相似文献
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土壤氧化铁光谱特征研究 总被引:27,自引:2,他引:25
土壤光谱反射特性的研究是土壤遥感的物理基础,土壤氧化铁含量影响土壤反射率。对采集的174个土样350~2 500 nm谱段的光谱数据进行分析,着重探讨下述3类光谱变量,寻找对土壤氧化铁含量敏感的光谱特征。1)原始光谱反射率及其各种变换形式;2)基于光谱吸收峰特征的变量,因为已知三价铁在870 nm附近有吸收峰存在,提取该吸收峰的面积、宽度、深度等变量;3)基于植被指数的变量,构建土壤氧化铁指数。研究结果表明,各类变量中土壤氧化铁指数对土壤氧化铁含量最敏感,建立相应的回归预测模型,模型拟合度R2为0.534。 相似文献
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In this paper the seven-step continuous extracting method was employed in the study of chemical forms of the six heavy metals Co,Zn,Pb,Cu,Cr and Mn,The result shows that the etals in the laterite are present in the chemical form of crystalline iron oxides and residues,and they are transformed towared organic and exchangeable forms in the surface soil.Linear regression analysis indicates that the above heavy metals have a positive correlation with the crystalline iron oxide minerals.The crystalline iron oxide minerals have a very important role to play in the enrichment of heavy metals,especially the solid components in the laterite. 相似文献
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YU Wenhui and LIU Congqiang The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou Graduate School of Chinese Academy of Sciences Beijing 《《地质学报》英文版》2005,79(3):343-348
1 Introduction Coherent element pairs (Y3+-Ho3+, Zr4+-Hf4+, Nb5+-Ta5+ and Sr2+-Eu2+) have the same valences and very similar ionic radii. They are seldom fractionated during silicate mineral/melt interaction systems because the partitioning of these element pairs between melts and minerals is tightly controlled by charge valence and crystal structure (lattice site size) or ionic radius. The concentration ratios of these pairs in igneous rocks are close to the chondritic values (Y/Ho=28, Zr… 相似文献
70.
无定形态游离氧化铁以其自身的特性及其脱水老化作用,对粘性土的物理性质、水理性质乃至工程性质产生了一定程度的影响。本文就粘性土的物理性质、水理性质及力学性质在无定形态游离氧化铁脱水过程中的变化进行了初步研究,期望对粘性土的土工测试方法及参数的合理测定有所裨益。 相似文献