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1.
25~75℃酸性NaCl溶液中方铅矿的溶解动力学   总被引:4,自引:0,他引:4  
在25~75℃、pH=0.43~2.45的1mol/LNaCl溶液中进行了方铅矿的溶解动力学实验。发现在远平衡条件下,方铅矿的溶解速率r与氢离子活度犤H+犦呈线性关系,溶解速率方程(速率定律)为:r=k犤H+犦,即对H+而言,溶解反应为一级。其中速率常数k为2.344×10-7mol/m2·s(25℃)、1.380×10-6mol/m2·s(50℃)、7.079×10-6mol/m2·s(75℃)。溶解反应的活化能为43.54kJ/mol,方铅矿的溶解机理为表面化学反应,速率决定步骤为表面配合物的离解。  相似文献   
2.
A new experimental calibration was undertaken in this study to get a more reliable sphalerite-galena sulfur isotope geothermometer. The experimental conditions selected in study were very similar to those of natural hydrothermal solution. The high-precision SF6 method was used in sulfur isotope analyses. The obtained calibration curve for sulfur isotope fractionation between sphalerite and galena can be expressed with the equation 10001nαSp-Gn= 0.74×106T-2+0.08.  相似文献   
3.
Electron transport properties of single crystal and polycrystalline natural mineral galena (PbS) samples from the Trep?a mine, Yugoslavia, were determined using the photoacoustic frequency transmission technique. Their thermal diffusivity (D T≈0.16 × 10?5 m2 s?1), the coefficient of diffusion (D between 0.15×10?2 0.16×10?2 m2 s?1) and lifetime of the excess carrier (τ≈35 μs and the front and rear recombination velocity (s g≈65.5 m s?1 and s b≈66.4 m s?1, respectively), were calculated by comparing the experimental results and the theoretical photoacoustic amplitude and phase signals. The lattice parameter obtained by X-ray work was a?=5.936?Å. The free carrier concentration of these single-crystal samples was measured using the Hall method (N?=?3×1018 cm?3). Measurements of the optical reflectivity of the same samples, as a function of wavelength, in the infrared and far infrared ranges, were performed. In the far infrared range a free electron plasma frequency was observed and numerically analyzed, using the least-squares fitting procedure. The values of optical parameters were calculated and the value of the free carrier concentration obtained by the Hall method was confirmed.  相似文献   
4.
研制的黄铁矿、黄铜矿、方铅矿和闪锌矿4个标准物质是国内首次成功研制的硫化物矿物成分分析标准物质。样品采用重选、磁选和电磁选等选矿技术提纯矿物,获得纯度大于95%的单矿物样品。黄铁矿和闪锌矿用棒磨机少量多级粉碎至0.147mm,方铅矿和黄铜矿用小型玛瑙球磨机粉碎至0.097mm。经单因素方差分析检验,均匀性符合要求。采用小包装在干燥、充氩气气氛中保存样品,使样品稳定性有足够保证。连续4年定期监测了样品中全硫含量,证明稳定性良好。样品由国内经计量认证的5家实验室采用多种分离富集手段、不同原理方法协同分析。标准值的确定依据数据分布特征而定,对于服从正态分布的元素,用算术平均值作为定值,对不服从正态分布的元素用多参数模式定值。共确定了56个标准值,16个参考值,6个信息值。该批标准物质于1994年12月通过了国家标准物质研究中心组织的专家复审,并于1995年4月被国家技术监督局批准为国家一级标准物质,标准号分别为GBW07267(GSM-1)、GBW07268(GSM-2)、GBW07269(GSM-3)、GBW07270(GSM-4)。  相似文献   
5.
通过对矿床中方铅矿的化学成分特征对比分析及同位素组成特征的研究,阐述了矿床的成因类型。并利用方铅矿热电性的标型特征,对矿床扩大深部找矿前景问题作了讨论。  相似文献   
6.
The Penjom Gold Mine is located 30 km from the Bentong-Raub Suture at the western boundary of the Central Belt in Peninsular Malaysia. Gold mineralization hosted within the vein system is associated with pyrite, arsenopyrite, and minor base metals including galena. Trace element and lead isotope analysis was undertaken on nine samples that represent two stages of galena formed during two tectonic events. Both the Pb isotopes and the trace elements show that the first stage galena within the mineralized areas at the footwall has different geochemical characteristics compared with galena in non mineralized areas in the hanging wall, suggesting that galena crystallized from two different ore fluids and probably at two different times. Higher Te, Se and Bi in the galena from the mineralized area may indicate hydrothermal fluids that migrate through the structural conduit and leached out the metal along the pathway that consist of dominant carbonaceous unit. The Pb isotopic ratio composition are transitional between the bulk crustal growth and an upper crustal growth curve, indicating that derivation was from arc rocks associated with continental crust or a crustal source that includes arc volcanic and old continental sedimentary rocks.  相似文献   
7.
一些有机物对Ph、Zn、Cu迁移与沉积作用的实验研究   总被引:1,自引:0,他引:1  
根据一些有机物在成矿溶液中存在的可能性,作者相继就中性、酸性与碱性氨基酸,以及酒石酸在铅、锌、铜迁移与沉积过程中的作用,进行了模拟实验研究。结果表明,在从90~210℃范围内,酸性氨基酸在热卤水中的存在,比中性和碱性氨基酸更有利于铅、锌、铜的活化、迁移。而酒石酸在热卤水中的存在,只在90℃或更低时,才是铅、锌等金属活化、迁移的最佳温度条件。且无论哪种有机物在热卤水中的存在,随作用时间及温度的变化,不同金属的活化、迁移明显不同。这表明,金属与氨基酸或其它有机物形成的易溶络合物,其稳定性不仅与金属、氨基酸等有机物的种类有关,而且还受温度的显著影响。  相似文献   
8.
Several Pb-Zn deposits and occurrences within Iran are hosted by Mesozoic–Tertiary-aged sedimentary and igneous rocks. This study reports new Pb isotope analyses for galena from 14 Pb-Zn deposits in the Alborz and Central Iran structural zones. In general, Pb isotope ratios are extremely variable with data plotting between the upper crustal and orogenic curves in a plumbotectonic diagram. The latter may be attributed to Pb inputs from crustal and mantle end-members. Most of the galena samples are characterized by high 207Pb/204Pb ratios, suggesting significant input of Pb from old continental crust or pelagic sediment. Pb isotope data also indicate that some of the deposits, which are hosted by sedimentary rocks in Central Iran and Alborz, have similar Pb isotopic compositions and hence suggest similar source regions. Most of the galenas yield Pb model ‘ages’ that vary between ~140 and ~250 Ma, indicating that mineralization resulted from the extraction of ore-bearing fluids from Upper Triassic–Lower Jurassic sequences. The similarity in Pb isotope ratios for the Pb-Zn deposits located within these zones suggests analogous crustal evolution histories. Our preferred interpretation is that Pb-Zn mineralization within the sedimentary and igneous rocks of the Central Iran and Alborz tectonic regions occurred following a Late Cretaceous–Tertiary accretionary stage of crustal thickening in Iran.  相似文献   
9.
洛宁某银铅矿床方铅矿热电性标型研究   总被引:1,自引:0,他引:1  
李忠烈 《矿产与地质》1992,6(3):215-217
洛宁某银铅矿床是近年来勘查的中型矿床。矿床银矿物种类多且含量高,共生金属矿物富含银。研究Ⅱ、Ⅲ、Ⅴ号矿体方铅矿的热电性标型特征,预测了下部矿体的延深情况,结果表明,该矿床Ⅱ号矿体方铅矿电子导型(N)热电系数具有浅部大,中部偏小,而深部又变大的特点,认为矿体向深部延深规模不大;而Ⅲ、Ⅴ号矿体浅部方铅矿热电系数变化范围大,显示混合导型,认为矿体有一定的延深。  相似文献   
10.
李忠烈 《地质与资源》1993,2(4):298-305
本文研究铁炉坪银铅矿床方铅矿的化学成分、同位素组成和方铅矿热电性等矿物学特征,提取了有一定参考价值的成因信息和找矿标志。认为铁炉坪银铅矿床系产于太古宇绿岩带背景上与岩浆活动有关的岩浆热液-变质热液矿床,其矿质主要来源于太古宇太华群结晶基底,指出方铅矿以含少量Sb,几乎不含Bi,含极少量Ag和富含Cu的标型特征,提出在矿区800-850m标高以下银铅矿体赋存的可能性很小。  相似文献   
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