- 行业: Mining
- Number of terms: 33118
- Number of blossaries: 0
- Company Profile:
The U.S. Bureau of Mines (USBM) was the primary United States Government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources.
Founded on May 16, 1910, through the Organic Act (Public Law 179), USBM's missions ...
A synthetic beryl glass colored by chromic oxide to resemble true emerald in color.
Industry:Mining
A synthetic corundum colored by vanadium oxide to resemble true alexandrite in some of its optical characters.
Industry:Mining
A synthetic fettling material, used for sintering open-hearth furnace bottoms. The approximate composition (variable) is 5.2% silica, 2.1% alumina, 10.5% ferric oxide, 13.4% lime, 66.5% magnesia (ignition loss, 2.3%). Martenite sinters more rapidly than magnesite, thereby reducing repair time; moreover, it is suitable for hot patching. Martenite is as wear resistant as magnesite and has no deleterious effect on the slag.
Industry:Mining
A synthetic reagent of the general nature of pine oil; used as frother in flotation process.
Industry:Mining
A system based on proximate analysis in which coals containing less than 31% volatile matter on the mineral-matter-free basis (Parr formula) are classified only on the basis of fixed carbon; i.e., 100% volatile matter. They are divided into five groups: above 98% fixed carbon; 98% to 92% fixed carbon; 92% to 86% fixed carbon; 86% to 78% fixed carbon; and 78% to 69% fixed carbon. The first three of these groups are called anthracites, and the last two are called bituminous coals. The remaining bituminous coals, the subbituminous coals, and the lignites are then classified into groups as determined by the calorific value of the coals containing their natural bed moisture; i.e., the coals as mined but free from any moisture on the surface of the lumps. The classification includes three groups of bituminous coals with moist calorific value from above 14,000 Btu/lb (32.5 MJ/kg) to above 13,000 Btu/lb (30.2 MJ/kg); three groups of subbituminous coals with moist calorific value below 13,000 Btu/lb to below 8,300 Btu/lb (19.3 MJ/kg); and two groups of lignitic coals with moist calorific value below 8,300 Btu/lb. The classification also differentiates between consolidated and unconsolidated lignites and between the weathering characteristics of subbituminous and lignitic coals.
Industry:Mining
A system delivering coal more efficiently in which a string of cars, with distinctive markings, and loaded to "full visible capacity," is operated without service frills or stops along the way for cars to be cut in and out, from the loading place to the point of delivery.
Industry:Mining
A system designed to prevent shaft conveyances from being moved or action signals from being transmitted, unless all shaft gates are closed.
Industry:Mining
A system employed with self-advancing supports on a longwall face in which alternate supports are advanced on each web of coal removed. To do this, alternate units have to be moved a distance equal to twice the web thickness--half before snaking and half after snaking.
Industry:Mining
