- 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 ...
The vertical height of a quarry or opencast face from top to toe; i.e., the height of overburden and coal, ore, or stone. A face height is chosen that can be reached by the excavator so that all scaling of loose material can be accomplished by the machine, thus eliminating the necessity for workers to go over the face on ropes to bar off loose ground. Where the height exceeds this figure, a form of benching may be adopted.
Industry:Mining
The vertical U-tube is the simplest type of pressure gage and consists either of a single U-shaped glass tube having a uniform bore with vertical arms or two separate glass tubes 3466 connected to a cistern. The level of the liquid in the vertical U-gage can be read easily to 0.1 in (2.5 mm) and in well-made instruments to 0.05 in (1.3 mm) water gage.
Industry:Mining
The visibility of an object under the microscope is directly proportional to the wavelength of light, and inversely to the aperture of lens.
Industry:Mining
The visible geometric figure observed when an etched flat surface of quartz is placed over a pinhole-focused light source.
Industry:Mining
The vitreous appearing components of coal, which in thin section are shown to have been derived from the woody tissues of plants--such as stems, limbs, branches, twigs, roots, including both wood and cortex--changed and broken up into fragments of greatly varying sizes through biological decomposition and weathering during the peat stage, and later flattened and transformed into coal through the coalification process, but still present as definite units.
Industry:Mining
The voltage at which an insulator or dielectric ruptures; or the voltage at which ionization and conduction begin in a gas or vapor.
Industry:Mining
The volume decrease that a clay undergoes in drying at room temperature.
Industry:Mining
