1) varzidan (#); 2) varzé (#)
Fr.: 1) pratiquer; 2) pratique
1a) To do habitually or regularly.
M.E. practisen, practizen; O.Fr. practiser "to practice," from M.L. practicare "to do, perform," from L.L. practicus "practical," from Gk. praktikos "practical."
1) Varzidan "to practice, perform; to accustom oneself to; to labor; to sow a field;"
Mid.Pers. warz- "to work, do, practice;"
Av. varəz- "to work, do, perform, exercise;" cf.
Gk. ergon "work;" Arm. gorc "work;" Lith. verziu "tie, fasten, squeeze,"
vargas "need, distress;" Goth. waurkjan; O.E. wyrcan "work,"
wrecan "to drive, hunt, pursue;" E. work;
PIE base *werg- "to work."
Actively following a specified career or way of life.
A professional man, especially in medicine and the law.
principle of action and reaction
parvaz-e žireš va vâžireš, ~ koneš va vâkoneš
Fr.: principe d'action et de réaction
Newton's third law of motion, which states that for every action there must be an equal and opposite reaction.
principle of least action
parvaz-e kamtarin žireš, ~ ~ koneš
Fr.: principe de moindre action
The principle that, for a system whose total mechanical energy is conserved, the path to be taken for the system from one configuration to another is the one whose action has the least value relative to all other possible paths and from the same configurations. Also called Maupertuis' principle, least-action principle.
A → radioactive → chemical element which is a malleable, shiny silver-gray metal; symbol Pa. → atomic number 91; → mass number of most stable isotope 231; → melting point greater than 1,600Â°C; → boiling point 4,026Â°C; calculated → specific gravity 15.37; → valence +4, +5. Protactinium has 24 → isotopes of which only three are found in nature. The most stable is protactinium-231 (→ half-life about 32,500 years); it is also the most common, being found in nature in all uranium ores in about the same abundance as radium. The element was discovered by Otto Hahn and Lise Meitner, who found one of its isotopes in 1917. It was isolated in 1934, by Aristid von Grosse.
Fr.: réaction proton-proton
Fr.: réaction pycnonucléaire
A nuclear reaction that takes place at high densities and relatively low temperatures. Pycnonuclear reactions are almost temperature independent and occur even at zero temperature. These reactions are extremely slow at densities typical for normal stars but intensify with increasing density. For example, carbon burns into heavier elements at densities over 1010 g cm-3.
quantum of action
Fr.: quantum d'action
Possessing, or pertaining to, → radioactivity.
sen yâbi-ye partow-žirâ
Fr.: datation radioactive
Determining the age of an object from the → radioactive decay of its constituting material. The technique consists of comparing the → abundance ratio of a → radioactive isotope to its → decay product. This will yield the number of half-lives that have occurred since the sample was formed. More specifically, if an object is made up of 50 % decay product then it has gone through 1 → half-life. 75% decay product equals 2 half-lives, 87.5% decay product equals 3 half-lives, 93.76% decay product equals 4 half-lives, and so on. For example, the decay product of → uranium-238 (238U) is → lead-206 (206Pb). The half-life of 238U is 4.5 billion years. Hence, if the sample has gone through two half-lives, it is 9 billion years old. See also: → radiocarbon dating.
Fr.: désintégration radioactive
Spontaneous emission by a nucleus of photons or particles.
Fr.: isotope radioactif
A → nuclide that is radioactive.
Fr.: nucléide radioactif
Fr.: déchets radioactifs
The radioactive by-products from the operation of a nuclear reactor or from the reprocessing of depleted nuclear fuel. Also known as nuclear waste.
The spontaneous disintegration of certain atomic nuclei, which is accompanied by the emission of either α- or β- particles and/or a γ rays.
The state of being rarefied, less dense.
M.E. rarefien, from M.Fr. rarefier, from L. rarefacere "make rare," from rarus "loose, wide apart, thin, infrequent."
Verbal noun from âlar present stem of âlaridan→ rarefy + -š, a suffix.
Fr.: onde de raréfaction
A pressure wave in a fluid generated by rarefaction. It travels in the opposite direction to that of a shock wave in the medium.
1) To act in response to an agent, influence, or stimulus.
The opposition to the flow of alternating current caused by the inductance and capacitance in a circuit rather than by resistance.
From → react + -ance a suffix of nouns.
Vâžirâyi state noun of vâžirâ agent noun of vâžiridan→ react.