240 resultados para Xikuangshan antimony deposit.


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稀矿山式铜矿是指赋存在昆阳群因民组地层中的铜铁矿床,其大地构造背景属于元古代裂谷带,大陆裂谷是超大型铜等多金属矿形成和分布的有利环境,在裂谷下部常发育异常地慢和岩浆源,裂谷空间上的多层次性使矿床具有明显垂向分带特征,其演化时间的长期性、脉动性和继承性便于多期成矿作用相互叠加、矿质的高度聚集。稀矿山式铜矿以落雪矿区稀矿山矿段最为典型,主要分布在因民落雪大乔地一稀矿山、滥山、磨子山,滥泥坪6-4巷、白锡腊和拖布卡地区。该类矿床广布于康滇地轴南段东川、武定一罗茨、元江、易门狮子山、金沙江南岸的花生坪、红门厂等地,已知中型铜矿床1处(稀矿山)、中型铁矿床2处(鹅头厂、笔架山)、小型铜(铁)矿床多处,上世纪90年代易门狮子山该类矿床的发现,表明该类矿床在东川-易门具找矿潜在远景。本文通过对东川矿区稀矿山式铜矿的常量元素、微量元素、包裹体、同位素及同位素定年等地球化学研究,获得以下认识:1.东川矿区地层(包括其下覆基底)和晋宁期碱基性岩中Cu等成矿元素背景值较高,且在蚀变过程中均能析出Cu等成矿元素。矿床中Cu等成矿物质来源复杂,以深源为主,部分来源于地层(因民组紫色层和落雪组白云岩)及基底地层:矿区内的退色蚀变作用可能是混合流体碱质交代改造作用的结果,对铜矿形成影响明显,是铜矿化的标志;2.该类矿床成矿流体属于中高温、中高盐度、高密度Na,(K+)Ca2+-SO42-(Cl-)型,以深部岩浆水为主,混有大量海水和变质水。矿床中发现了富NZ包裹体,可能是矿床形成时,深大断裂活动、碱基性岩浆带来地球深部(上地慢和下地壳)物质并形成的成矿流体,在氧化一去挥发分作用过程中所形成;3.铁矿体被铜矿体包围,铁矿石被铜矿细脉穿插,说明铜矿化的形成晚于铁矿化。黄铜矿单矿物的Re-05同位素年龄研究表明其成矿年龄为826士230Ma,接近矿区碱基性岩年龄,与昆阳裂谷内其它类型铜矿成矿时代相当,均属于晋宁-澄江期;4.东川矿区晋宁一澄江期碱基性岩侵入活动明显,常作为因民组复杂角砾岩胶结物和岩脉(体)产出,多分布于深大断裂及其派生的次级构造附近,明显受南北向小江深大断裂走滑运动引起的右行旋扭及其派生构造控制,与“落因破碎带”和“铜矿分布”较吻合,均为“Z”字形。表明东川矿区铜矿形成与深大断裂及其派生次级构造和,宁-澄江期碱基性岩侵入活动关系密切;5.昆阳裂谷内的多数铜矿同位素成矿年龄多集中在9.0亿-6.5亿年之间,属于晋宁-澄江期,与Redina大陆裂解时限相当。表明裂谷内铜矿床的形成可能与Rodinia大陆裂解有关。因此,总结东川稀矿山式铜矿成矿模式为沉积(Fe、Cu)-热液叠加(Cu)改造:晋宁-澄江期,小江深大断裂发生走滑运动,在东川矿区造成右行旋扭及其派生构造,形成“Z”,字形落因破碎带,同时来自深源(下地壳或上地慢)碱基性岩浆侵入,不仅带来了大量Cu等成矿物质,更重要的是提供了热源,促使地层水(落雪组白云岩和因民组紫色层)循环,与富碱(Na和K)岩浆水混合,形成富碱中高温高盐度流体。因民组紫色层与其底部角砾岩接触带,具有较高的空隙度和渗透率,有利于成矿流体的运移和成矿。在这种混合流体作用下,地层中Cu等成矿物质析出,叠加改造了初始铜矿化最终形成稀矿山式铜矿。

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利用吉林大栗子铁矿纯菱铁矿样品,系统测量了菱铁矿在空气环境的的磁化特征,揭示出其饱和曙剩磁(SIRM)、剩磁矫顽力(HCR)和居里温度(TC)随加热温度升高而秘珠系列变化,菱放氧化中准稳定态性矿物磁赤铁矿是中间产物之一,并且具有较高的热稳定性,X射线衍射和穆斯堡尔效应等分析结果证实了岩石磁学研究所揭示的菱铁矿氧化中磁性矿物转变过程,菱铁矿氧化过程中结晶结构的转变可能会影响其氧化产物的磁性特性。

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High dose Mn was implanted into semi-insulating GaAs substrate to fabricate embedded ferromagnetic Mn-Ga binary particles by mass-analyzed dual ion beam deposit system at room temperature. The properties of as-implanted and annealed samples were measured with X-ray diffraction, high-resolution X-ray diffraction to characterize the structural changes. New phase formed after high temperature annealing. Sample surface image was observed with atomic force microscopy. All the samples showed ferromagnetic behaviour at room temperature. There were some differences between the hysteresis loops of as-implanted and annealed samples as well as the cluster size of the latter was much larger than that of the former through the surface morphology. (C) 2004 Elsevier B.V. All rights reserved.

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In order to develop the ultra-large scale integration(ULSI), low pressure and high density plasma apparatus are required for etching and deposit of thin films. To understand critical parameters such as the pressure, temperature, electrostatic potential and energy distribution of ions impacting on the wafer, it is necessary to understand how these parameters are influenced by the power input and neutral gas pressure. In the present work, a 2-D hybrid electron fluid-particle ion model has been developed to simulate one of the high density plasma sources-an Electron Cyclotron Resonance (ECR) plasma system with various pressures and power inputs in a non-uniform magnetic field. By means of numerical simulation, the energy distributions of argon ion impacting on the wafer are obtained and the plasma density, electron temperature and plasma electrostatic potential are plotted in 3-D. It is concluded that the plasma density depends mainly on both the power input and neutral gas pressure. However, the plasma potential and electron temperature can hardly be affected by the power input, they seem to be primarily dependent on the neutral gas pressure. The comparison shows that the simulation results are qualitatively in good agreement with the experiment measurements.

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We propose a plasma channel scheme to obtain an improved table-top laser driven fusion neutron yield as a result of explosions of large deuterium clusters irradiated by an intense laser pulse. A cylindrical plasma channel is created by two moderate intensity laser prepulses at the edge of a deuterium cluster jet along which an intense main laser pulse propagates several nanoseconds later. With the aid of this plasma channel, the main laser pulse will be allowed to deposit its energy into the central region of the deuterium gas jet where the cluster sizes are larger and the atomic density is higher. The plasma channel formation and its impact on the deuterium ion energy spectrum and the consequent fusion neutron yield have been investigated. The calculated results show that a remarkable increase of the table-top laser driven fusion neutron yield would be expected.

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We investigate the mechanism of selective metallization on glass surfaces with the assistance of femtosecond laser irradiation followed by electroless plating. Irradiation of femtosecond laser makes it possible to selectively deposit copper microstructures in the irradiated area on glass surfaces coated with silver nitrate films. The energy-dispersive X-ray (EDX) analyses reveal that silver atoms are produced on the surface of grooves formed by laser ablation, which serve as catalysis seeds for subsequent electroless copper plating. (C) 2008 Elsevier B.V. All rights reserved.

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A new composition content quaternary-alloy-based phase change thin film, Sb-rich AgInSbTe, has been prepared by DC-magnetron sputtering on a K9 glass substrate. After the film has been subsequently annealed at 200degreesC for 30 min, it becomes a crystalline thin film. The diffraction peak of antimony (Sb) are observed by shallow (0.5 degree) x-ray diffraction in the quaternary alloy thin film. The analyses of the measurement from differential scanning calorimetry (DSC) show that the crystallization temperature of the phase change thin film is about 190degreesC and increases with the heating rate. By Kissinger plot, the activation energy for crystallization is determined to be 3.05eV. The reflectivity, refractive index and extinction coefficient of the crystalline and amorphous phase change thin films are presented. The optical absorption coefficient of the phase change thin films as a function of photon energy is obtained from the extinction coefficient. The optical band gaps of the amorphous and crystallization phase change thin films are 0.265eV and 1.127eV, respectively.