polar optical effect
71Ship gun fire-control system — Mk 37 Director c1944 with Mk 12 (rectangular antenna) and Mk 22 orange peel Ship gun fire control systems (GFCS) enable remote and automatic targeting of guns against ships, aircraft, and shore targets, with or without the aid of radar or optical …
72Theories of general anaesthetic action — Structures of general anaesthetics widely used in medicine. A general anaesthetic (or anesthetic) is a drug that brings about a reversible loss of consciousness. These drugs are generally administered by an anaesthetist/anaesthesiologist in order …
73Communications satellite — A communications satellite (sometimes abbreviated to COMSAT) is an artificial satellite stationed in space for the purpose of telecommunications. Modern communications satellites use a variety of orbits including geostationary orbits, Molniya… …
74Loudspeaker — For other uses, see Loudspeaker (disambiguation). An inexpensive, low fidelity 3½ inch speaker, typically found in small radios …
75Contact lens — Contacts redirects here. For the software application, see Address book. A pair of contact lenses, positioned with the concave side facing upward …
76Diamond dust — For diamond dust used in manufacturing, see diamond tool. For other uses, see Diamond dust (disambiguation). Diamond dust is a ground level cloud composed of tiny ice crystals. This meteorological phenomenon is also referred to simply as ice… …
77Keratoconus — Classification and external resources The conical cornea that is characteristic of keratoconus ICD 10 H …
78Scattering parameters — or S parameters are properties used in electrical engineering, electronics engineering, and communication systems engineering describing the electrical behavior of linear electrical networks when undergoing various steady state stimuli by small… …
79clay mineral — any of a group of hydrous aluminum silicate minerals, as kaolinite, illite, and montmorillonite, that constitute the major portion of most clays. [1945 50] * * * Any of a group of important hydrous aluminum silicates with a layered structure and… …
80Timeline of historic inventions — The timeline of historic inventions is a chronological list of particularly important or significant technological inventions. Note: Dates for inventions are often controversial. Inventions are often invented by several inventors around the same… …
