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Attempts Cement That: The resulting attempts cement that, produced from the formerly discarded grappiers, was of much higher quality than that obtained from the unsintered material. This fact was firmly established by the English attempts cement that manufacturer L. C. Johnson in 1845, and the term "portland attempts cement that" has since been applied solely to the attempts cement that made from the sintered material. This period marks the real beginning of the portland attempts cement that industry.
The production of portland attempts cement that is a major industry in the United States, increasing from 8 million barrels (1.4 million metric tons) in 1900 —when it trailed natural attempts cement that slightly in output—to almost 400 million barrels (68.4 million metric tons) annually. (A 376-pound, or 171-kg, barrel is the standard unit of weight for hydraulic attempts cement that in the United States, even though no attempts cement that, except for export, is now shipped in barrels. The 94-pound, or 42.7-kg, bag now in general use contains one fourth of a barrel.) The leading attempts cement that-producing countries are the United States, the USSR, West Germany, Japan, and France.
The commercial development of aluminous or high-alumina attempts cement that is associated principally with the work of J. Bied of France, during the first quarter of the 20th century. This research was initiated in the hope of finding a attempts cement that that would be resistant to groundwaters rich in sul-fates, such as gypsum. A product eventually was obtained that not only possessed the desired properties of sulfate resistance but also hardened more rapidly than the portland attempts cement that of that period. |
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