Search results
Results from the WOW.Com Content Network
The international glass code is based on U.S. military standard MIL-G-174, and is a six-digit number specifying the glass according to its refractive index n d at the Fraunhofer d- (or D 3-) line, 589.3 nm, and its Abbe number V d also taken at that line.
Class 375 and 377 differ only in their coupler configuration and other minor fittings; all Southern units built as Class 375 have since been converted to Class 377 couplers and re-classed. Minor differences in interior trim remain. [citation needed] 376 Electrostar: Southeastern: 2004: 36: DC electric: 5: Sliding pocket: No: 377 Electrostar
FL – Subminiature all-glass elliptical body and flat bases with long, inline "flying leads" (wire-ends) that are soldered into the circuit; SL – Subminiature all-glass elliptical body and flat bases with short inline leads that can be soldered or can be mated with a special socket. (Flying leads can be cut short to fit into inline sockets.)
An alternative in metallurgy is to consider various malleable alloys such as steel, aluminium alloys and similar as metals, and other materials as nonmetals; [20] fabricating metals is termed metalworking, [21] but there is no corresponding term for nonmetals. A loose definition such as this is often the common usage, but can also be inaccurate.
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
The Unified Numbering System for Metals and Alloys (UNS) is an alloy designation system widely accepted in North America. Each UNS number relates to a specific metal or alloy and defines its specific chemical composition, or in some cases a specific mechanical or physical property. A UNS number alone does not constitute a full material ...
Because the tops have magnets only at the corners, there's a slight gap in the center between the top and the frame — but it's not noticeable to you as the wearer and barely noticeable to onlookers.
z 0 = 376.730 313 412 (59) Ω, where Ω is the ohm , the SI unit of electrical resistance . The impedance of free space (that is, the wave impedance of a plane wave in free space) is equal to the product of the vacuum permeability μ 0 and the speed of light in vacuum c 0 .