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GB900514A
|
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Improvements in or relating to the treatment of zinc sulphide pigments
|
|
US2185911A
|
|
Direct batch process for the production of iron and steel
|
|
US2045639A
|
|
Process for the production of molten iron or steel by the direct method
|
|
US2011400A
|
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Process of treating zinciferous iron ores
|
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US1915748A
|
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Process for manufacturing barium sulphate of definite granule size
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US1900994A
|
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Purifying of natural heavy spar
|
|
US1923497A
|
|
Purifying of natural heavy spar
|
|
CA338204A
|
|
Barium compound
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