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13-letter words containing el

  • electron tube — (electronics)   (Or tube, vacuum tube, UK: valve, electron valve, thermionic valve, firebottle, glassfet) An electronic component consisting of a space exhausted of gas to such an extent that electrons may move about freely, and two or more electrodes with external connections. Nearly all tubes are of the thermionic type where one electrode, called the cathode, is heated, and electrons are emitted from its surface with a small energy (typically a Volt or less). A second electrode, called the anode (plate) will attract the electrons when it is positive with respect to the cathode, allowing current in one direction but not the other. In types which are used for amplification of signals, additional electrodes, called grids, beam-forming electrodes, focussing electrodes and so on according to their purpose, are introduced between cathode and plate and modify the flow of electrons by electrostatic attraction or (usually) repulsion. A voltage change on a grid can control a substantially greater change in that between cathode and anode. Unlike semiconductors, except perhaps for FETs, the movement of electrons is simply a function of electrostatic field within the active region of the tube, and as a consequence of the very low mass of the electron, the currents can be changed quickly. Moreover, there is no limit to the current density in the space, and the electrodes which do dissapate power are usually metal and can be cooled with forced air, water, or other refrigerants. Today these features cause tubes to be the active device of choice when the signals to be amplified are a power levels of more than about 500 watts. The first electronic digital computers used hundreds of vacuum tubes as their active components which, given the reliability of these devices, meant the computers needed frequent repairs to keep them operating. The chief causes of unreliability are the heater used to heat the cathode and the connector into which the tube was plugged. Vacuum tube manufacturers in the US are nearly a thing of the past, with the exception of the special purpose types used in broadcast and image sensing and displays. Eimac, GE, RCA, and the like would probably refer to specific types such as "Beam Power Tetrode" and the like, and rarely use the generic terms. The cathode ray tube is a special purpose type based on these principles which is used for the visual display in television and computers. X-ray tubes are diodes (two element tubes) used at high voltage; a tungsten anode emits the energetic photons when the energetic electrons hit it. Magnetrons use magnetic fields to constrain the electrons; they provide very simple, high power, ultra-high frequency signals for radar, microwave ovens, and the like. Klystrons amplify signals at high power and microwave frequencies.
  • electron volt — a unit of energy equal to that attained by an electron falling unimpeded through a potential difference of one volt; 1.602 × 10-19 joule
  • electrooptics — the technology that deals with the production, control, and detection of light by electrical devices
  • electrophiles — Plural form of electrophile.
  • electrophilic — (of a molecule or group) having a tendency to attract or acquire electrons.
  • electrophones — Plural form of electrophone.
  • electrophonic — Relating to electronic equipment to produce sound (this adjectival sense is not comparable).
  • electrophorus — A device for repeatedly generating static electricity by induction.
  • electroplated — Simple past tense and past participle of electroplate.
  • electroplates — Third-person singular simple present indicative form of electroplate.
  • electroscopes — Plural form of electroscope.
  • electrostatic — Of or relating to stationary electric charges or fields as opposed to electric currents.
  • electrostrong — (physics) describing the combination of the electromagnetic and strong nuclear forces.
  • electrothermy — the use of electrically produced heat for therapeutic purposes
  • electrotyping — The act or process of making electrotypes.
  • electrotypist — an electrotyper
  • electrovalent — (of bonding) resulting from electrostatic attraction between positive and negative ions; ionic.
  • elephant fish — a large marine fish, Callorhinchus milii, of southwest Pacific waters, having a snout resembling an elephant's trunk
  • elephant seal — either of two large earless seals, Mirounga leonina of southern oceans or M. angustirostris of the N Atlantic, the males of which have a long trunklike snout
  • elephantbirds — Plural form of elephantbird.
  • elephantiasis — A condition in which a limb or other part of the body becomes grossly enlarged due to obstruction of the lymphatic vessels, typically by the nematode parasites that cause filariasis.
  • elevator shoe — a shoe designed to increase the wearer's height
  • eleventh hour — If someone does something at the eleventh hour, they do it at the last possible moment.
  • elgin marbles — a group of 5th-century bc Greek sculptures originally decorating the Parthenon in Athens, brought to England by Thomas Bruce, seventh Earl of Elgin (1766–1841), and now at the British Museum
  • ellipticities — Plural form of ellipticity.
  • embellishment — A decorative detail or feature added to something to make it more attractive.
  • encephalocele — (medicine) A form of hernia of the brain and its membranes through an opening in the skull.
  • endoskeletons — Plural form of endoskeleton.
  • endotheliomas — Plural form of endothelioma.
  • enfield rifle — a breech-loading bolt-action magazine rifle, usually .303 calibre, used by the British army until World War II and by other countries
  • enjoy oneself — to have a good time
  • ensorcellment — Enchantment, bewitchment.
  • epithelialize — Cover or become covered with epithelial tissue, e.g. during the healing of a wound.
  • epitheliomata — Plural form of epithelioma.
  • epitrachelion — The liturgical vestment worn by priests and bishops of the Orthodox Church as the symbol of their priesthood, corresponding to the Western stole.
  • eretz yisrael — the Holy Land; Israel
  • escort vessel — ship that accompanies another
  • euler-chelpin — Hans (Karl August) von. 1873–1964, Swedish biochemist, born in Germany: shared the Nobel prize for chemistry (1929) with Sir Arthur Harden for their work on enzymes: father of Ulf von Euler
  • evangelically — In an evangelical manner, concerning evangelism.
  • evangelistary — a book containing passages from the gospels to be used as part of the liturgy
  • evil-smelling — having an very offensive smell
  • excellentness — The state or the quality of being excellent.
  • explanatively — in an explanative manner
  • explicatively — in an explicative or explanatory manner
  • exploratively — in an explorative manner
  • extracellular — Situated or taking place outside a cell or cells.
  • facultatively — In a facultative manner.
  • family jewels — a man's genitals
  • fare-you-well — a state of perfection: The meal was done to a fare-thee-well.
  • fashion model — sb employed to show off designer clothes
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