Fr.: mécanisme de Eley-Rideal
A → chemical reaction on solid surfaces in which one atom or molecule is → adsorbed on the catalyst surface, and another reacts directly from the gas phase. This type of mechanism may occur preferentially on very small → dust grains, where transient heating events prevent weakly bound species from remaining and in larger grains at high temperatures. Compare with the → Langmuir-Hinshelwood mechanism.
Proposed in 1938 by D. D. Eley (1914-2015), a British chemist and Professor of Physical Chemistry and E. K. Rideal (1890-1974), an English physical chemist.
After the Gk. geometrician and educator at Alexandria, around 300 B.C., who applied the deductive principles of logic to geometry, thereby deriving statements from clearly defined axioms.
Fr.: division euclidienne
hendese-ye Oqlidosi (#)
Fr.: géométrie euclidienne
The geometry based on the postulates or descriptions of Euclid. One of the critical assumptions of the Euclidean geometry is given in his fifth postulate: through a point not on a line, one and only one line be drawn parallel to the given line. See also → non-Euclidean geometry.
Fr.: espace euclidean
A space in which the → distance between any two points is given by the → Pythagorean theorem: d2 = (Δx)2 + (Δy)2 + (Δz)2, where d is distance and Δx, Δy, and Δz are differential → Cartesian coordinates. Euclidean n-space Rn is the set of all column vectors with n real entries.
Idea, from L. idea "idea," pre-Platonic Gk. idea "form, semblance, nature, fashion," in Plato "a timeless, universal archetype of existents; ideal prototype," literally "look, form," from idein "to see," from PIE *wid-es-ya-, suffixed form of base *weid- "to know, to see;" cf. Pers. bin- "to see" (present stem of didan); Mid.Pers. wyn-; O.Pers. vain- "to see;" Av. vaēn- "to see;" Skt. veda "I know."
Miné "idea," related to Pers. maneš "disposition, temperament, greatness of soul," minu "heaven, paradise," also equivalent to Ger. Geist in recent philosophical translations, došman "enemy," pašimân "penitent, regretful," pežmân "sad, mournful," šâdmân "joyful, cheerful, pleased," ârmân "desire; → ideal;" dialectal (Šuštar) mana "(he) thinks, imagines," (Tarq-e Natanz) môna "to imagine, suppose;" Mid.Pers. mênidan "to think, consider," mên "thought, idea," mênišn "thought, thinking, mind, disposition," mênitâr "thinker," mênôg "spiritual, immaterial, heavenly," from Av. man- "to think," mainyeite "he thinks," manah- "mind, thinking, thought; purpose, intention," mainyu- "mind, mentality, mental force, inspiration," traditionally translated as "spirit," Angra Mainyu "hostile mentality" (Mod.Pers. Ahriman); O.Pers. maniyaiy "I think," Ardumaniš- (proper noun) "upright-minded," Haxāmaniš- (proper noun, Hellenized Achaemenes, founder of the Achaemenian dynasty) "having the mind of a friend;" cf. Sogdian mân "mind;" Skt. man- "to think," mánye "I think," manyate "he thinks," mánas- "intelligence, understanding, conscience;" Gk. mainomai "to be angry," mania "madness," mantis "one who divines, prophet;" L. mens "mind, understanding, reason," memini "I remember," mentio "remembrance;" Lith. mintis "thought, idea;" Goth. muns "thought," munan "to think;" Ger. Minne "love," originally "loving memory;" O.E. gemynd "memory, thinking, intention;" PIE base *men- "to think, mind; spiritual activity."
1) (n.) ârmân (#), minevâr; 2) (adj.) ârmâni (#), mineyi, minevâr
1) (n.) A standard of perfection, beauty, or excellence.
M.E. ydeall, from L.L. idealis "existing in idea," from L. → idea.
Ârmân "ideal" in Mod.Pers., traditionally "desire; hope; grief," variants
armân, urmân, prefixed from mân, "thought, mind," → idea.
The first element may be related to Av. armaē- "in peace, still; quietly;"
PIE base *er[ə]- "to be still" (cf. Skt. īrmā (adv.) "quiet,
still, being in the same place;" Gk. erôé "calm, peace;" O.H.G. rouwa
"rest"), as in Av. armaē.šad- "sitting quietly,"
armaē.štā- "standing still, stagnant." Therefore, Pers. ârmân
may be related to Av. *armaē.manah- (PIE *ermen-)
"thought in peace, quiet mind."
šâre-ye ârmâni, ~ minevâr
Fr.: fluide idéal
gâz-e ârmâni, ~-e minevâr
Fr.: gaz idéal
Theoretical gas assumed to consist of perfectly elastic molecules of negligible volume and mutual attraction force. Also called → perfect gas.
ideal gas law
qânun-e gâz-e ârmâni, ~ ~ minevâr
Fr.: loi des gaz parfaits
An → equation of state that relates pressure (P), temperature (T), and volume (V) of an ideal or → perfect gas: PV = nRT, where n is the number of → moles of gas present and R is the → universal gas constant. Equivalently: PV = NkT, where N is the number of atoms of gas present and k is → Boltzmann's constant.
ideal MHD condition
butâr-e MHD-ye ârmâni
Fr.: MHD idéale
Magnetohydrodynamics of a plasma with very large (infinite) conductivity. In this limit, Ohm's law reduces to E = -v x B, where E represents electric field, B magnetic field, and v the fluid velocity.
Any one of a variety of systems of philosophical thought, which would make the ultimate reality of the Universe expressible or intangible only in terms of idea in mind, rather than in terms of matter in space.
hendese-ye nâ-oqlidosi (#)
Fr.: géométrie non-euclidienne
Any of several geometries which do not follow the postulates and results of Euclidean geometry. For example, in a non-Euclidean geometry through a point several lines can be drawn parallel to another line. Or, the sum of the interior angles of a triangle differs from 180 degrees. According to Einstein's general relativity theory, gravity distorts space into a non-Euclidean geometry.
Fr.: espace pseudo-euclidien
A real vector space of dimension n having a symmetric bilinear form (x, y) such that in some basis e1, ..., en, the quadratic form (x2) takes the form x12 + ... + xn - 12 - xn2. Such bases are called orthonormal.