aperiodic damping mirâyi-ye nâdowreyi Fr.: amortissement apériodique A system in which the → damping is great enough to prevent oscillation. |
periodic dowreyi (#) Fr.: périodique Recurring at regular intervals of time. Adjective of → period. |
periodic comet dombâledâr-e dowreyi Fr.: comète périodique A comet with a period of less than 200 years. Also called short-period comet. |
periodic function karyâ-ye dowreyi Fr.: fonction périodique A function f(x) if for all x, f(x + P) = f(x), where P is a positive constant. The least value of P > 0 is called the period of f(x). |
periodic motion jonbeš-e dowreyi Fr.: mouvement périodique Any motion that recurs in identical forms at equal intervals of time. |
periodic system râžmân-e dowreyi Fr.: système périodique Arrangement of the → chemical elements in the → periodic table. |
periodic table jadval-e dowreyi (#) Fr.: tableau périodique An arrangement of the → chemical elements
in order of their → atomic numbers in such a way
as to demonstrate periodic similarities and trends in physical and chemical properties.
Elements with similar properties are arranged in the same column
(called a group), and elements with the same number of
→ valence electrons, or number of electrons in the outer shell,
are arranged in the same row (called a period).
Under the latest recommendations from IUPAC (the International Union of Pure
and Applied Chemistry), the groups are labelled 1 to 18 from left
to right (1988, Pure and Applied Chemistry 60, 431).
Also called Mendeleev's table. |
periodic term tarm-e dowre-yi Fr.: terme périodique In perturbation theory used in celestial mechanics, a term that indicates a bounded disturbance which recurs regularly. → secular term. |
periodic wave mowj-e dowre-yi Fr.: onde périodique An oscillatory motion in which each point is repeatedly displaced at equal time intervals. |
periodicity dowreigi Fr.: périodicité A state or condition characterized by regular repetition in time or space. |
quasiperiodic motion jonbeš-e cunân-dowreyi Fr.: mouvement quasipériodique In a dynamical system, a form of motion that is regular but never exactly repeating. Quasiperiodic motion appears when the system contains two or more incommensurate frequencies. |