Witwatersrand gold deposits formed by volcanic rain, anoxic rivers and Archaean life
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چکیده
منابع مشابه
Silicosis on the Witwatersrand Gold Mines.
Silicosis is an incurable non-infectious occupational disease. It is one of the pneumoconioses, a generic group of long diseases associated with dusty occupations. Silicosis is caused by continuous inhalation of microscopic particles of free silica (quartz) dust measuring from one to three microns in diameter (a micron is equivalent to 0,0001 centimetres). If these particles penetrate to the de...
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Our aim in this work is the synthesis and study optical and structural properties of gold nanoparticles.Gold (III) chloride trihydratewas taken as metal precursor, ascorbic acid at the presence of an appropriate amount of NaOH as reducing agent and polyvinylpyrrolidonek-30 (PVP K-30) as a stabilizing and capping agent. The reaction was performed in high-speed stirring rate at room temperature.S...
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ژورنال
عنوان ژورنال: Nature Geoscience
سال: 2015
ISSN: 1752-0894,1752-0908
DOI: 10.1038/ngeo2344