410 km discontinuity sharpness and the form of the olivine α-β phase diagram: resolution of apparent seismic contradictions     

George R. Helffrich  Bernard J. Wood 《Geophysical Journal International》1996,126(2):F7-F12

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流体的热力学前缘研究   总被引：12，自引：1，他引：12  

张哲儒 《地学前缘》1996,3(3):80-88

总结了当前国内外关于流体的热力学前缘研究领域如下：（１）流体体系的ｐ－Ｖ－Ｔ－ｘ相关系研究，主要对象是Ｈ２Ｏ－ＣＯ２－盐类多组分体系高温高压下相图的实验和理论研究。（２）矿物在流体中的溶解度及溶解后在流体中溶解类型的形式和热力学性质——平衡常数（或Ｇｉｂｂｓ自由能）及各种偏摩尔性质的研究。（３）流体热力学模型化研究，已研制出大量的计算机软件，包括多种矿物、溶解类型的热力学数据库和模拟热液平衡、矿物溶解性质、反应路径和水—岩相互作用的实用程序。（４）超临界流体的相关系和化学反应等有许多特殊的性质，对认识地球内部的演化将有重要意义。（５）新技术新方法的发展，使分析单个矿物包裹体成分变成了现实。  相似文献   

近场源二极激电法在贫硫银金矿床的应用效果     

饶跃民  姜永兰 《矿产与地质》1996,10(4):268-272

在管地贫硫银金矿床进行了近场源二极激电法的应用研究，获得了三高一低的次级低缓激电异常，即高ηｓ、Ｒ_２、Ｊｓ，低ρｓ，表明用次级参数表示的激电弱异常要明显，为增加矿量，提高地质找矿效果起了积极作用。  相似文献   

二维TIM中的传播矩阵与面波相速度     

阎贫  张中杰 《物探化探计算技术》1996,18(2):108-112

本文利用横向各向同性介质（ＴＩＭ）中的传播矩阵和面波形成条件，导出了面波波慢度方程。对瑞利波给出了各向同性及横向各向同性弹性介质中其相速度的解析解；对于勒夫波，给出了横向各向同性介质中的波慢度方程。  相似文献   

钛（Ⅳ）的反相萃取柱色层新体系研究及应用     

谭龙华  唐祖光 《矿物岩石》1997,17(3):94-97

本文研究了以ｃＨＣｌ＝８ｍｏｌ·Ｌ－１盐酸为移动相，以聚四氟乙烯负载的钽试剂－ＣＨＣｌ３为固定相反相萃取层析钛（Ⅳ）的新体系，柱上层析的钛用ｃＨＣｌ＝３ｍｏｌ·Ｌ－１盐酸洗脱后经二安替比林甲烷光度法测定，不仅钛回收率可达１００％，并可使钛（Ⅳ）与多种离子分离。能用于矿物岩石类复杂样品及其他物质中钛的分离富集与测定，方法简便快速。  相似文献   

人工合成宝石级翡翠的研究   总被引：4，自引：0，他引：4  

朱成明  金志升 《矿物学报》1997,17(3):245-249

本文以对化学试剂为原料，用静奇谈怪论同温高压固相转变法合成宝石级翡翠的机理和工艺条件进行了实验研究，测定了与硬玉化学组分相同的玻璃物质的高压熔融曲线和固相转变的区域，提出了在熔融曲线左侧附近固相区生长优质硬玉的观点，以及在宝石级悲翠合成中的若干技术问题。  相似文献   

Partitioning of elements between peridotite and H₂O at 2.0–3.0 GPa and 900–1100°C, and application to models of subduction zone processes     

John C. Ayers  Sondra K. Dittmer  Graham D. Layne 《Earth and Planetary Science Letters》1997,150(3-4):381-398

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Study on simulation of spatial correlative earthquake ground motion field     

Xiao-Jun Li  Feng-Xin Zhao  Yu-Xian Hu 《地震学报(英文版)》1997,10(2):267-271

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Aerosol polarized phase function and single-scattering albedo retrieved from ground-based measurements     

Zhengqiang Li  Philippe Goloub  Claude Devaux  Xingfa Gu  Yanli Qiao  Fengsheng Zhao  Hongbin Chen 《Atmospheric Research》2004,71(4):233-241

Aerosol optical parameters, polarized phase function and single-scattering albdeo, have been retrieved from ground-based sun photometer measurements in Beijing 2003. The measured aerosol optical thickness varies from 0.12 to 0.77 with an average value of 0.39. The measured Ångström coefficient ranges from 0.75 to 1.47 with an average value of 1.21. The retrieved single-scattering albedo at 870 nm is within the 0.76–0.94 range and the average value is 0.85, suggests there are considerable aerosol absorptions in Beijing. The maximum value of retrieved polarized phase function at 870 nm ranges from 0.068 to 0.225 with an average value of 0.16, and it illustrates good correlations with the Ångström coefficient, i.e. the relative size of aerosol particles. Analyses of measurements and theoretical calculations show the polarized phase function is sensitive to aerosol size distribution and complex refractive index, especially the imaginary part of the refractive index which denotes aerosol light absorbing effects. These results suggest that the polarized phase function is an effective and unique aerosol optical parameter and is able to improve the retrieval of aerosol physical properties.  相似文献   

Molecular modeling of the 10-Å phase at subduction zone conditions     

Jianwei Wang 《Earth and Planetary Science Letters》2004,222(2):517-527

Molecular dynamics (MD) modeling of the 10-Å phase, Mg₃Si₄O₁₀(OH)₂·xH₂O, with x=2/3, 1.0 and 2.0 shows complex structural changes with pressure, temperature and water content and provides new insight into the structures and stabilization of these phases under subduction zone conditions. The structure(s) of this phase and its role as a reservoir of water in the mantle have been controversial, and these calculations provide specific predictions that can be tested by in situ diffraction studies. At ambient conditions, the computed structures of talc (x=0) and the 10-Å phases with x=2/3 and 1.0 are stable over the 350-ps period of the MD simulations. Under these conditions, the 10-Å phases show phlogopite-like layer stacking in good agreement with previously published structures based on powder X-ray diffraction data for samples quenched from high-pressure and high-temperature experiments. The calculations show that the 10-Å phase with x=2.0 is unstable at ambient conditions. The computed structures at P=5.5 GPa and T=750 K, well within the known stability field of the 10-Å phase, change significantly with water content, reflecting changing H-bonding configurations. For x=2/3, the layer stacking is talc-like, and for x=1.0, it is phlogopite-like. The calculations show that transformation between these two stackings occurs readily, and that the talc-like stacking for the x=2/3 composition is unlikely to be quenchable to ambient conditions. For x=2.0, the layer stacking at P=5.5 GPa and T=750 K is different than any previously proposed structure for a 10-Å phase. In this structure, the neighboring basal oxygens of adjacent magnesium silicate layers are displaced by b/3 (about 3 Å) resulting in the Si atoms of one siloxane sheet being located above the center of the six-member ring across the interlayer. The water molecules are located 1.2 Å above the center of all six-member rings and accept H-bonds from the OH groups located below the rings. The b/3-displaced structure does not readily transform to either the talc-like or phlogopite-like structure, because neither of these stackings can accommodate two water molecules per formula unit. There is likely to be a compositional discontinuity and phase transition between the b/3-displaced phase and the phase with phlogopite-like stacking. The simulations reported here are the first to use the recently developed CLAYFF force field to calculate mineral structures at elevated pressures and temperatures.  相似文献