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Closeup of the undercutting bar and results on a Plasser & Theurer ballast cleaner in use in Hungary in 2009. A cutter bar runs beneath sleeper level excavating all of the ballast under the sleepers to a specified, variable depth. A conveyor then moves the ballast into the cleaner, where it gets forced through a mesh by a shaking chamber. [4]
Automatic quartz is a collective term describing watch movements that combine a self-winding rotor mechanism [1] (as used in automatic mechanical watches) to generate electricity with a piezoelectric quartz crystal as its timing element. Such movements aim to provide the advantages of quartz without the inconvenience and environmental impact of ...
Common material for the reaction tubes include alumina, Pyrex, and fused quartz, or in the case of corrosive materials molybdenum or tungsten tubes can be used. The tube furnace was invented in the first decade of the 20th century and was originally used to manufacture ceramic filaments for Nernst lamps and glowers. [2]
The Spring Drive uses a conventional mainspring [3] and barrel [4] along with automatic and/or stem winding to store energy, just as in a mechanical watch. [3] However, the escapement and balance wheel in mechanical watches is replaced by Seiko's Tri-synchro Regulator system, a phase-locked loop wherein a rotor, which Seiko refers to as a "glide wheel", is powered by the mainspring barrel via ...
Pickling is a metal surface treatment used to remove impurities, such as stains, inorganic contaminants, and rust or scale from ferrous metals, copper, precious metals and aluminium alloys. [1]
An air purifier or air cleaner is a device which removes contaminants from the air in a room to improve indoor air quality. These devices are commonly marketed as being beneficial to allergy sufferers and asthmatics , and at reducing or eliminating second-hand tobacco smoke .
HEPA filters are designed to arrest very fine particles effectively, but they do not filter out gasses and odor molecules. Circumstances requiring filtration of volatile organic compounds, chemical vapors, or cigarette, pet or flatulence odors call for the use of an activated carbon (charcoal) or other type of filter instead of or in addition to a HEPA filter. [20]
The Lavet-type stepping motors used in analog quartz clock movements which themselves are driven by a magnetic field (generated by the coil) can be affected by external (nearby) magnetism sources, and this may impact the rotor sprocket output. As a result, the mechanical output of analog quartz clock movements may temporarily stop, advance or ...