نتایج جستجو برای: quartz vein
تعداد نتایج: 82061 فیلتر نتایج به سال:
With the complicated geology of vein deposits, their irregular and extremely skewed grade distribution, confined nature gold, there is a propensity to overestimate or underestimate ore grade. As result, numerous estimation approaches for mineral resources have been developed. It was investigated in this study by using five machine learning algorithms estimate highly gold data vein-type at Quart...
Gold bearing veining linked to transcrustal fault zones in the Transantarctic Mountains (northern Victoria Land, Antarctica)" (2007). Related Publications from ANDRILL Affiliates. Paper 20. Summary Gold mineralization is associated with the paleo-Pacific margin of Gondwana and is related to processes of subduction/accretion and magmatism. Northern Victoria Land (Antarctica) was part of this mar...
Abstract Dongping is the largest Au-Te vein deposit (~120 t Au) in North China craton, but its age, origin, and setting remain unsolved. Here, we integrate paragenesis, geochemistry, situ U-Pb geochronology of garnet to constrain timing possible origin deposit. Gold mineralization at hosted Shuiquangou alkaline complex (ca. 401–390 Ma) dominated by quartz-sulfide veins with minor ores adjacent ...
Occupational exposure to high levels of respirable quartz can result in respiratory and other diseases in humans. The Mine Safety and Health Adminstration (MSHA) regulates exposure to respirable quartz in coal mines indirectly through reductions in the respirable coal mine dust exposure limit based on the content of quartz in the airborne respirable dust. This reduction is implemented when the ...
Quartz fibers are used in high energy physics experiments as the active medium in high radiation area calorimetry. Quartz fibers are also used in the transmission of optical signals. Even though quartz does not damage by moderate amounts of irradiation, the clad of the fibers and the protective coating (buffer) do damage reducing light transmission. Various types of quartz fibers have been irra...
In this study we have measured exposure levels to quartz in different parts of the slate industry in Alta, Northern Norway. Full shift personal samples were collected from the breathing zones of outdoor and indoor workers in the slate quarries and a slate factory. The quartz content of respirable dust was between 7 and 41%. The slate factory had the lower quartz levels although 41% of total and...
Indium Mineralization in a Sn-Poor Skarn Deposit: A Case Study of the Qibaoshan Deposit, South China
Indium (In) is commonly hosted in Sn-rich deposits but rarely reported in Sn-poor deposits. However, an In-rich and Sn-poor skarn deposit, the Qibaoshan Cu-Zn-Pb deposit, has been identified in south China. Geochemical analyses were undertaken on 23 samples representing the following mineral assemblages: sphalerite-pyrite, pyrite-chalcopyrite, pyrite-sphalerite-galena-chalcopyrite, pyrite, magn...
Fracturing quartz produces silica-based radicals on the fracture planes and generates hydroxyl radicals (.OH) in aqueous media. .OH production has been shown to be directly associated with quartz-induced cell damage and phagocyte activation in vitro. This .OH production in vitro is inhibited by desferrioxamine mesylate, an Fe chelator, indicating involvement of a Fenton-like reaction. Our objec...
this research was conducted from july 1993 to june 1994 on the total population (711 workers) of a glass factory. the purpose of this study was to determine the quantitative free silica (quartz) in respiratory zone of workers in glass industry. field samples including 50 samples total dust and 37 samples respirable dust and standard simplex were collected on membrane filters using skc dust samp...
Interleukin-10 (IL-10) can downregulate expression of several proinflammatory cytokines including chemokines. This study investigated the role of IL-10 in the acute response of the rat lung to quartz particles. Intratracheal instillation of rats with 1 mg of quartz produced an inflammatory and cytotoxic response demonstrated by increased bronchoalveolar lavage (BAL) fluid neutrophils, lactate d...
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