| http://www.w3.org/ns/prov#value | - In the case of the powered support assemblies used in underground mining, it has been known for a long time to use spray nozzles for suppressing the fine coal dust detrimental to health and arising during the extraction of, for example, coal by means of a winning machine, such as in particular a plow or shearer loader, the working face being sprayed with spray water by said spray nozzles just befo
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