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glycol

(Encyclopedia)glycol glīˈkōl [key], dihydric alcohol in which the two hydroxyl groups are bonded to different carbon atoms; the general formula for a glycol is (CH2)n(OH)2. The most important glycol is the simpl...

digital circuit

(Encyclopedia)digital circuit, electronic circuit that can take on only a finite number of states. That is contrasted with analog circuits, whose voltages or other quantities vary in a continuous manner. Binary (tw...

dogfish

(Encyclopedia)dogfish, name for a number of small sharks of several different families. Best known are the spiny dogfishes (family Squalidae) and the smooth dogfishes (family Triakidae). Spiny dogfishes have two sp...

feedback

(Encyclopedia)CE5 Basic feedback control system feedback, arrangement for the automatic self-regulation of an electrical, mechanical, or biological system by returning part of its output as input. A simple exam...

parthenogenesis

(Encyclopedia)parthenogenesis pärˌthənōjĕnˈəsĭs [key] [Gr.,=virgin birth], in biology, a form of reproduction in which the ovum develops into a new individual without fertilization. Natural parthenogenesis ...

foehn

(Encyclopedia)foehn fān, Ger. fön [key], warm, dry wind that occurs on the leeward slopes of a ridge of mountains. The term was originally applied to a wind of the Alps but is now used as a generic term for all w...

fuzzy logic

(Encyclopedia)fuzzy logic, a multivalued (as opposed to binary) logic developed to deal with imprecise or vague data. Classical logic holds that everything can be expressed in binary terms: 0 or 1, black or white, ...

indium

(Encyclopedia)indium ĭnˈdēəm [key], a metallic chemical element; symbol In; at. no. 49; at. wt. 114.818; m.p. 156.6℃; b.p. about 2,080℃; sp. gr. 7.31 at 20℃; valence +1, +2, or +3. Indium is a soft, malle...

pit viper

(Encyclopedia)pit viper, poisonous snake of the family Crotalidae, primarily a New World family. Like the Old World true vipers (family Viperidae), pit vipers have long, hollow, erectile fangs that are folded back ...

ceramics

(Encyclopedia)ceramics sərămˈĭks [key], materials made of nonmetallic minerals that have been permanently hardened by firing at a high temperature, or objects made of such materials. Most ceramics resist heat a...