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采用断续流动进样氢化物发生-双道原子荧光光谱法测定地下水中的砷、汞,确定仪器的最佳条件,考察了酸度,预还原剂和还原剂用量和载流流速的影响以及共存元素的干扰情况,在选定的条件下,砷的检出限0.0109μg/L,相对标准偏差为1.10%,回收率为95.7~102.2,汞的检出限0.0023μg/L,相对标准偏差0.87%,回收率为95.5~103.0. 相似文献
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原子荧光光谱法直接测定载金炭样品中的砷 总被引:1,自引:0,他引:1
建立了原子荧光光谱法直接测定载金炭样品中砷的分析方法。采用硝酸溶样,原子荧光光谱法直接测定载金炭样品中的砷。该方法具有准确度高、流程短、精密度好、速度快等优点。比对试验结果表明,该方法测定结果与全谱直读ICP法结果一致。 相似文献
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按照测量不确定度评定方法,对氢化物发生-原子荧光光谱法测定地球化学样品中铋结果进行不确定度评定。研究发现原子荧光光谱法测定地球化学样品中铋含量的不确定度主要来源于样品制备过程、标准溶液配制过程、校准曲线拟合过程、重复性测量以及分析仪器的不确定度等。通过对各分量的不确定度进行量化,得出合成标准不确定度和扩展不确定度。结果表明最大的不确定度来源于样品制备过程。当样品中铋含量为24.76μg/g时,其扩展不确定度(k=2)为1.40μg/g。 相似文献
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载金炭对汞有较强的吸附性,易造成黄金生产工艺污染及活性炭吸附金的活性降低,需测定载金炭中的汞含量以监控汞的危害。应用目前测定汞的分析方法在样品前处理过程中需要高温去除基体炭,但容易造成汞的挥发损失。本文采用固体测汞仪在不需样品前处理及不加入其他试剂的情况下实现了载金炭中总汞的直接测定,载金炭最优热解条件为空气流速0.8~1.2 L/min,蒸发温度680~740℃,汞的回收率达到99%以上。样品在热解过程中基体炭转化成二氧化碳,二氧化碳的干扰可由仪器自动消除,所以基体炭对汞的测定无明显影响。全流程的管道不足50 cm,且整个管道处于较高温度之下,通过加大空气流速可快速消除管道上残余的汞,减少了记忆效应的影响。本方法的相对标准偏差小于8.0%,测定下限为0.014μg/g,汞的测试结果与原子荧光光谱法基本吻合。 相似文献
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采用氢化物发生-原子荧光光谱法,对地下水、地表水、饮用水以及生活污水中的砷含量进行测定,对氢化物发生条件、载流酸类型、酸的浓度、还原掩蔽剂浓度等影响因素进行详细探讨,选出优化的测定条件:以5%的盐酸为载流酸性介质,以20 g·L-1的硼氢化钠(溶解于2 g·L-1的氢氧化钠稳定剂中)为还原剂,以50 g·L-1硫脲-抗... 相似文献
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应用氢化物发生-原子荧光光谱法同时测定滑石中痕量砷和汞,并对样品的浸取方法及共存元素和实验奈件进行了研究。结果表明,用浓盐酸浸取样品,砷、汞溶出量最大;加入硫脲-抗坏血酸溶液后,滑石中共存元素铝、铁、钙、铜、铅、镉不干扰砷、汞的测定。方法的检出限为砷0.047 mg/L,汞3.9 ng/L;回收率为砷107.5%~109.2%,汞103.3%~130.0%;精密度(RSD,n=11)为砷0.6%,汞0.7%。建立的氢化物发生-原子荧光光谱同时测定滑石中砷、汞含量的分析方法能满足日常检验的要求。 相似文献
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水浴浸提-氢化物发生-原子荧光光谱法同时测定地质样品中痕量砷和汞 总被引:2,自引:2,他引:0
采用盐酸-硝酸混合酸(盐酸-硝酸-水体积比3∶1∶4)水浴浸取地质样品,在样品消解后的母液中直接加入硫脲-抗坏血酸混合溶液,以氢化物发生-原子荧光光谱法同时测定地质样品中的痕量砷和汞。方法检出限为砷0.033 6 ng/mL,汞0.003 7 ng/mL;相对标准偏差(RSD,n=1)为砷1.1%,汞3.0%。对国家一级标准物质GBW 07109~GBW 07114、GBW 07301~GBW 07312、GBW 07401~GBW 07408中的砷和汞进行测定,测定值与标准值相吻合。 相似文献
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D. C. Harris 《Mineralium Deposita》1990,25(1):S3-S7
Processing of most gold ores, other than placers, involves conventional gravity separation and direct cyanidation. The difficult (or refractory) gold ores are not amenable to direct cyanidation and these ores require detailed mineralogical investigations to assist in determining the recovery processes. There are six mineralogical factors that can contribute to poorer recoveries. These are 1. the nature of the gold-containing minerals, 2. the grain size of the gold minerals, 3. the nature of the gangue minerals, 4. the associated sulfide minerals, 5. coatings on gold, and 6. chemically bound or invisible gold.Geological Survey of Canada Contribution Number 13089 相似文献
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胶东地区探明金储量超过5000t,是我国最重要的金矿集区。玲珑金矿区位于胶东西北部招-平断裂北段,具有典型含金石英脉矿床的特征。矿区部分矿段产出富碲铋化物的明金矿石,是研究富碲铋化物金矿床成因和金超级富集机制的理想对象。通过显微岩相学观察、扫描电镜及电子探针分析,首次对胶东玲珑金矿区富碲铋化物明金矿石的矿物组合和形成机制进行了较为详细的研究。玲珑金矿区含明金矿石中的金矿物主要为含银自然金,成色整体较高,平均为894。共发现了五种与自然金共生的碲化物,分别是辉碲铋矿、碲铋矿、碲银矿、碲铋银矿和碲镍矿,其中辉碲铋矿含量最多。通过矿物共生组合研究及物理化学条件分析,确定成矿流体的碲逸度范围为-12.6相似文献
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Two styles of gold dendrites are variably developed at the McLaughlin Mine. The most abundant occurrence is hosted by amber-coloured hydrocarbon-rich opal. Silica likely precipitated from a boiling hydrothermal fluid and complexed with immiscible hydrocarbons forming an amorphous hydrocarbon-silica phase. This phase likely scavenged particulate gold by electrostatic attraction to the hydrocarbon-silica phase. The dendritic nature of the gold is secondary and is the result of dewatering of the amorphous hydrocarbon-silica phase and crystallization of gold into syneresis fractures. The second style of dendritic gold is hosted within vein swarms that focused large volumes of fluid flow. The dendrites occur along with hydrocarbon-rich silica at the upper contact of the vein margins which isolated the dendrites allowing sufficient time for them to grow. In a manner similar to the amber-coloured opal, the dendrites may have formed by scavenging particulate gold by electrostatic attraction to the hydrocarbon-silica phase. 相似文献
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A New Genetic Type of Gold Deposits-Meso-Epithermal Carbonate-Type Gold Deposits as Exemplified by the Baguamiao Suprlarge Gold Deposit 总被引:1,自引:0,他引:1
Gold deposits of the meso-epithermal carbonate type were first proposed based on the study of the Baguamiao gold deposit.This new type of gold deposits has many unique characteristics as follows:(1)Obviously strata-bound.The gold deposits are hosted in Middle Devonian turbidite formations;(2)Structrually controlled.Struc-ture is an important factor leading to metallogenesis of this type of gold deposits.The shape and distribution of orebodies are controlled by byittle-ductile shear zones;(3)Multi-stage wall-rock alteration.According to the characteristics of mineral assemblage,gold mineralization can be classified into three stages in association with various wall-rock al-terations.Wall-rock alterations closely genetically related to the gold mineralization are ankerization ,silicification,pyrrhotization and pyritization ;(4)Mineral compositions of the orebodies are mainly pyrrhotite,pyrite,marcasitolite,chalcopyrite,quartz,ankerite,and sericite.Gold mineralization is associated closely in space and time with iron sulfides;(5)Rare elements and REE in ores are low in contents relative to those of the crust.Au content varies from 1.91g/t to 11.15g/t ,averaging 5.5g/t;(6)Studies of sulfur,hydrogen,oxygen and carbon isotopes in main gangue minerals (quartz and ankerite)indicate that fluids and ore-forming materials came from deep-seated sources;(7)Three types of inclusions are recognized in terms of their composition and the vapor amounts of inclusions.The homogenization temperatures of inclusions range from 210℃to 310℃,averaging 230℃,showing that this type of gold deposits belongs to the meso-epithermal type;(8)Metallogenic age of this type of gold deposits is similar to that of the collision between the Yangtze Plate and the North China Plate,indicating that gold deposits of this type are genetically related to continental-margin plate activity. 相似文献
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矿产勘查活动往往会带来一定的生态环境影响,如何评估这些影响是当前矿产勘查所面临的迫切问题之一。本研究以广东省金矿资源最为集中的粤西金矿带为例,采用生态系统服务价值核算方法,利用单位面积生态环境价值,结合植被恢复时间和矿产资源潜力,量化评估粤西金矿带内的四个主要已知矿区勘查活动生态环境影响,进一步推测量化评估金矿带内其他具有类似成矿地质条件的预测单元勘查活动生态环境影响。评估结果表明:(1)粤西金矿带勘查活动生态环境影响成本较低,相对于其矿产资源潜力带来的社会经济效益而言,微乎其微;(2)广东省粤西金矿带下一步勘查工作方向仍应重点集中在金牛A类预测区、新洲A类预测区与高村A类预测区等资源潜力大、单位资源量生态环境成本低的区域;(3)本研究提出的勘查活动生态环境影响量化评估方法具有易操作、适用性广等特点,可用于其他地理环境下的勘查活动生态环境影响量化评估。 相似文献
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小秦岭金矿田构造演化与金矿成矿作用 总被引:1,自引:0,他引:1
依据小秦岭金矿田的地质构造穿插关系和同位素年龄资料,建立了本区构造、岩浆、成矿事件序列。在此基础上,将小秦岭地区的构造演化划分为6个阶段:褶皱变质、韧性剪切变形、稳定升降、韧-脆性断裂转化、断裂活动、抬升剥蚀阶段。对小秦岭金矿田的成矿时代,成矿深度、矿床成因等地质问题,给出了构造地质学方面的判据。 相似文献