Results 111 to 120 of about 580,177 (156)
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QUARTZ AND PNEUMOCONIOSIS IN COALMINERS
The Lancet, 1981In a routine survey of 623 miners in one colliery, 21 men, an unusually high number, showed radiological progression of simple pneumoconiosis in spite of generally low exposures to mixed coalmine dust. Comparison of the dust exposures of the 21 men with those of matched controls without pneumoconiosis showed highly significant differences in the ...
J.A. Dick +3 more
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International Geology Review, 1977
Electron microscopy was used to investigate scratches on cleaved synthetic quartz and amethyst. The transverse bands in a scratch are microcracks. When the hardness of the indenter is less than the hardness of the quartz, a formation of Dauphine microtwins is observed near the scratch.
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Electron microscopy was used to investigate scratches on cleaved synthetic quartz and amethyst. The transverse bands in a scratch are microcracks. When the hardness of the indenter is less than the hardness of the quartz, a formation of Dauphine microtwins is observed near the scratch.
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Nature, 1935
PYRITES (FeS2) in the form of small crystals and specks of a brassy-yellow colour may be found frequently in quartz. Four pieces of Brazilian quartz, containing pyrites inclusions, have now been found which are of unusual interest.
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PYRITES (FeS2) in the form of small crystals and specks of a brassy-yellow colour may be found frequently in quartz. Four pieces of Brazilian quartz, containing pyrites inclusions, have now been found which are of unusual interest.
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2013
The drive to improve the performance of clocks inevitably led on a path from large lumbering mechanical clock mechanisms with long periods of oscillation to increasingly smaller mechanisms that run at much higher frequency. The hair spring-balance wheel clocks evolved over the eighteenth and nineteenth centuries into mechanical instruments of such ...
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The drive to improve the performance of clocks inevitably led on a path from large lumbering mechanical clock mechanisms with long periods of oscillation to increasingly smaller mechanisms that run at much higher frequency. The hair spring-balance wheel clocks evolved over the eighteenth and nineteenth centuries into mechanical instruments of such ...
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The Journal of Chemical Physics, 1963
X-ray- and uv-excited thermoluminescence in natural quartz has been investigated by studying the properties of synthetic samples. The results for a large number of natural samples, including single crystals, outcrop specimens, and core-hole samples showed that most of them had four prominent glow peaks in common.
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X-ray- and uv-excited thermoluminescence in natural quartz has been investigated by studying the properties of synthetic samples. The results for a large number of natural samples, including single crystals, outcrop specimens, and core-hole samples showed that most of them had four prominent glow peaks in common.
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Geological Society of America Bulletin, 1964
The impurity content of quartz—substitutional elements plus foreign inclusions—is different for different rocks and may be sufficiently distinctive to allow correlation within the same igneous or metamorphic rock mass and distinction between different quartz-bearing rocks. An application to provenance is suggested.
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The impurity content of quartz—substitutional elements plus foreign inclusions—is different for different rocks and may be sufficiently distinctive to allow correlation within the same igneous or metamorphic rock mass and distinction between different quartz-bearing rocks. An application to provenance is suggested.
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Machine Learning Prediction of Quartz Forming‐Environments
Journal of Geophysical Research: Solid Earth, 2021Yu Wang, Zhaoliang Hou, Kun-feng Qiu
exaly
Quartz and quartz-feldspathic sands from Uzbekistan
Glass and Ceramics, 1986S. G. Gafurdzhanov, M. Z. Zakirov
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