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新疆京希-伊尔曼德金矿床矿化类型热液蚀变及流体包裹体证据  [PDF]
肖龙,王方正,Begg,Graham,付民禄
矿床地质 , 2002,
Abstract: 京希-伊尔曼德金矿床位于新疆伊宁县北部。金矿(化)体赋存于下石炭统大哈拉军山组下部粗碎屑岩中同时受控于断裂构造和岩眭。该矿床形成于浅成低温环境的高硫化体系中。初始强酸胜的含金热液流体在沿断裂构造向上迁移时,与围岩发生水-岩反应形成由内向外的物理化学梯度变化,表现为以硅化(发育酸胜淋滤形成的多孔状石英构造)、高级泥化和泥化构成蚀变分带。迪开石+高岭石+多孔状.硅化石英等热液蚀变矿物构成高级泥化主蚀变。金主要沉淀富集于硅化带和高级泥化带。蚀变矿物组合及流体包裹体资料确定的成矿流体胜质为:酸眭(pH早期为2~3,晚期为3~5)、低盐度[w(NaCI)eq<5%]及低温(成矿温度为180~270℃)。
伊犁京希―伊尔曼德金矿床的热液蚀变及成矿流体演化特征  [PDF]
地质学报 , 2001,
Abstract: 京希-伊尔曼德金矿床的热液蚀变在空间上有明显的分带性,中心蚀变带以强烈的硅化为主,典型的蚀变矿物组合为石英或玉髓和地开石,中间带为高级泥化带,以地开石-高岭石-石英或玉髓为特征;外带为以蒙脱石-高岭石-伊利石-其他粘土矿物等矿物组合为主的泥化带,蚀变强度和矿物组合的分带性是温度、压力和化学梯度的反映,是流体在不断的水或流体-岩石反应和成分交换的产物。该矿床成矿流体演化过程为:早期酸性(pH=2-3)含矿流体在沿断裂上升过程中,受围岩灰岩中的流体(pH为中性)缓冲,在其进入高渗透性的碎屑岩层时,流速和水-岩石或流休-岩石反应大大加快,并在与大气降水的混合作用下,pH值逐步升高(3-5),产生了流体的温度及成分梯度,在温度和压力迅速下降的条件下,金及蚀变矿物沉淀、结晶生长,形成了蚀变空间分带,中心带保存完好的多孔状石英和地开石等高级泥化矿物组合说明该矿床是高硫化热液体系作用下的产物。
西天山阿希、京希-伊尔曼得金矿床成矿流体包裹体研究及矿化类型探讨  [PDF]
冯娟萍,王居里
西北地质 , 2005,
Abstract: 阿希、京希-伊尔曼得金矿床3个主成矿阶段形成的石英中的原生流体包裹体数量少、个体小,包裹体以单液相为主,气液两相者气液比小,一般为5%~10%。激光拉曼光谱成分分析显示液相成分以H2O为主,普遍含有一定量的CO2、CH4;气相中以CO2和CH4为主,含有较高的SO2和N2;一些样品中还出现了C2H4、C6H6、C4H6等有机化合物。其均一温度为90~275℃,成矿流体盐度为0~3.7wB(NaCleq)%,估算的成矿深度为0.40~0.80km左右,属于典型的浅成低温热液型金矿床。其成矿作用与强烈的次生石英岩化关系极为密切,发生了次生石英岩化矿化,形成含金次生石英岩型矿石。
Thermal decomposition of illite
Araújo, José Humberto de;Silva, Nagib Francisco da;Acchar, Wilson;Gomes, Uílame Umbelino;
Materials Research , 2004, DOI: 10.1590/S1516-14392004000200024
Abstract: the effect of heat treatment on illite in air at temperatures ranging from 750 to 1150 °c was studied using the m?ssbauer effect in 57fe. the dependence of the m?ssbauer parameters and relative percentage of the radiation absorption area was measured as a function of the firing temperature. the onset of thermal structural decomposition occurred at 800 °c. with rising temperature, the formation of hematite (fe2o3) increased at the expense of the silicate mineral.
Thermal decomposition of illite
Araújo José Humberto de,Silva Nagib Francisco da,Acchar Wilson,Gomes Uílame Umbelino
Materials Research , 2004,
Abstract: The effect of heat treatment on illite in air at temperatures ranging from 750 to 1150 °C was studied using the M ssbauer effect in 57Fe. The dependence of the M ssbauer parameters and relative percentage of the radiation absorption area was measured as a function of the firing temperature. The onset of thermal structural decomposition occurred at 800 °C. With rising temperature, the formation of hematite (Fe2O3) increased at the expense of the silicate mineral.
基于InSAR的南京大胜关大桥纵向位移监测与分析
InSAR-based longitudinal displacement monitoring and analysis on Nanjing Dashengguan bridge
 [PDF]

黄其欢,丁幼亮,王一安,尹方舟
- , 2017, DOI: 10.3969/j.issn.1001-0505.2017.03.028
Abstract: 为解决传统桥梁位移监测方法传感器数量有限、监测信息不全面以及监测成本高等问题,以京沪高铁南京大胜关大桥为对象,研究了基于合成孔径雷达干涉(InSAR)的大跨桥梁结构纵向位移监测方法.利用欧空局Sentinel-1A卫星IW模式影像,建立了适用于大跨桥梁纵向位移监测的InSAR时间序列分析方法,得到了全桥1 723个相干目标的纵向位移信息.分析结果表明,大桥纵向位移主要由热膨胀引起,采用InSAR技术可以准确识别全桥纵向位移,且支座处纵向位移与结构温度的相关性模型与该桥支座位移传感器建模结果吻合.
To resolve the problem of the traditional bridge displacement monitoring methods, such as the limited numbers of the monitoring sensors, the incomprehensive monitoring information, the high costs and so on, a monitoring method for the longitudinal displacement of long-span bridges based on the interference of the synthetic aperture radar(InSAR)is proposed by taking the Nanjing Dashengguan bridge as the research subject. The InSAR time series analysis method for longitudinal displacement monitoring of the long-span bridges is established by using the interferometric wide(IW)model image of the Sentinel-1A satellite of the European Space Egency(ESA), and the longitudinal displacement information of 1 723 coherent targets is obtained. The results show that the longitudinal displacement of the bridge is mainly caused by the thermal expansion of the bridge structure. The InSAR technique can accurately identify the longitudinal displacement of the whole bridge. Furthermore, the correlation model between the longitudinal displacement of the bridge and the structural temperature is in agreement with the modeling results of the bridge displacement sensors
高速列车作用下南京大胜关大桥动位移响应分析
Analysis of the dynamic displacement responses of the Nanjing Dashengguan Bridge under high-speed trains
 [PDF]

赵瀚玮,丁幼亮,李爱群
ZHAO Hanwei
, DING Youliang, LI Aiqun

- , 2018,
Abstract: 基于南京大胜关大桥健康监测系统的速度监测数据,获取桥梁各部位在高速列车作用下的准静态位移响应和自由振动位移响应。讨论桥梁结构准静态位移响应、自由振动位移响应与位移动力系数的空间分布特征。建立桥梁结构在高速列车作用下的准静态位移响应、自由振动位移响应与位移动力系数概率密度模型。研究结果表明:南京大胜关大桥的主梁横向、墩顶纵向的准静态位移响应幅值与自由振动位移响应幅值存在桥梁中部(中间墩处)响应最大的空间分布特征;在长期运营过程中,南京大胜关大桥各部位单次过车的准静态位移响应服从Log-Logistic分布,自由振动位移响应服从t Location-scale分布,位移动力系数服从Burr分布。
Based on the long-term monitoring data of velocity on the structural health monitoring system of the Nanjing Dashengguan Bridge, the quasi-static displacement and free vibrating displacement of various bridge parts were obtained. The features of spatial distribution of train-induced quasi-static displacement, free vibrating displacement and displacement dynamic load factor (DLF) of the bridge structure were discussed. The model of probability density of train-induced quasi-static displacement, free vibrating displacement and displacement DLF of the bridge structure were established. The main conclusions obtained are as follows: The horizontal quasi-static displacement and free vibrating displacement of beam, the longitudinal of quasi-static displacement and free vibrating displacement of the pier top, obey the principle that the largest values occur at the center of the bridge (near the mid-pier) along the longitudinal direction; in the long-term operation of the bridge, the quasi- static displacements of each train passing obey the Log-Logistic distribution, the free vibrating displacements obey t Location-scale distribution, and the displacement DLFs obey the Burr distribution
Evaluation of the Adsorption of Hexavalent Chromium on Kaolinite and Illite  [PDF]
Omar Ajouyed, Charlotte Hurel, Nicolas Marmier
Journal of Environmental Protection (JEP) , 2011, DOI: 10.4236/jep.2011.210155
Abstract: The adsorption of hexavalent chromium on Kaolinite and Illite was studied in order to evaluate their potential for the reduction of hexavalent chromium mobility and their possible application for the treatment of polluted sediment. The influence of various parameters affecting the adsorption of hexavalent chromium, such as the pH of aqueous solution, the ionic strength and the initial metal ion concentration were investigated. The optimal pH range corresponding to the hexavalent chromium adsorption maximum on the Kaolinite and Illite is 2 - 4 and 2 - 2.6, respectively. The results showed that hexavalent chromium sorption on Kaolinite and Illite was strongly influenced by the pH, the ionic strength and the initial metal ion concentration. Langmuir and Freundlich adsorption isotherms are employed to understand the nature of adsorption at room temperature. The characteristic parameters for each isotherm have been determined. This showed that the Freundlich isotherm model well described the equilibrium data. The data suggest that the charge of the clay mineral surface is one of the main factors controlling hexavalent chromium desorption at alkaline pHs.
Kinetic model for the smectite to illite transformation in active geothermal systems
Ji Junfeng,P. R. L. Browne,Liu Yingjun,Wang Henian
Chinese Science Bulletin , 1998, DOI: 10.1007/BF02884645
Abstract: The smectite to illite transformation in active geothermal systems of New Zealand can be simulated by a first-order reaction kinetic model, which provides direct estimates about the minumum ages of active geothermal systems themselves. The derived kinetic values show that the smectite to illite transformation is sensitive to both temperature and time.
Kinetic model for the smectite to illite transformation in active geothermal systems

Ji Junfeng,P R L Browne,Liu Yingjun,Wang Henian,

科学通报(英文版) , 1998,
Abstract: The smectite to illite transformation in active geothermal systems of New Zealand can be simulated by a first-order reaction kinetic model, which provides direct estimates about the minumum ages of active geothermal systems themselves. The derived kinetic values show that the smectite to illite transformation is sensitive to both temperature and time.
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