<< < -es -iv -ti 21 a p abe abs abs aca acc acc acr act ada adh Adr aer AGB air Alf Alg all alp alt AM amo ana And ang ani ano Ant Ant apa apo app app Ara Arc ari Arr ash ass ast ast asy atm ato att aut ave axi Bab bal Bal bar bar bea Bek Bes bia Big bin bin bip biv bla bli blu Boh Bol Bos bou bra bri bro buo cal cal can cap car Car cat cat CCD Cen cen CH cha cha che Che chr cir cir cit cla clo clo clu Coa coe coh col col col com com com com com com com com Com con con con con con con con con con con con con Cop Cor cor cor cos cos cou cou Cow cre cri cro cry cur cya Cyg dan dar dat de- deb dec dec ded def deg del dem den dep des det dev dia dif dif dih dio Dir dis dis dis dis dis dis DO don dou dow dro dur dwa dyn Dys ear ebb ecl edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ equ esc eth Eur Eve exa exc exe exi exp exp ext ext ext fac fal far fed Fer fer fie fin fir fis fla flo flu fol for for fou fra fre Fre fro fut G-t gal gal gam gas Gau Gem gen geo geo geo gia Gli Gol gra gra gra gra gre gri gui H I Hag hal har hat He- hea hel Hel her Hes hie hig his hom hor hot Hub Hug hur hyd hyd hyg hyp ice ide ima Ima imp imp inc inc ind ine inf inf inf ing inn ins ins int int int int int int int int inv Io ion iro isl iso iso Jac jet jud jur Kel Kep kil Klo Kui Lag lam Lap Lar lat law lea len lep Lib lig lim lin lin Lio lit loc LOF lon Lor low lum lun Lup Lyo mac mag mag mag mag mag mai man Mar mas mas mat Max mea mec Meg Mer Mer met met Met mic Mid Mil min Mir mit mod mod mol mon Mor mou mul mul mys nan Nat nau nec neo neu nev New NGC no nom non non nor not nuc nuc num nut obj obs obs occ ocu oft ome Oor ope opp opt opt orb ord ori ort osc out ove oxi pai pan par par par par pas pea pen per per per per Per per pha phi pho pho pho phy pio Pla pla pla pla Pla plu Poi pol pol pol poo pos pos pot pra pre pre pre pre pri pri pro pro pro pro pro Pro pro pse pul pur qua qua qua qua que rac rad rad rad rad rad rad ran rar ray rea rea rec rec red red ref ref reg rel rel rel ren res res res res ret rev Ric rig rin roc roo rot rot Rus Sac sal sat sca sca Sch sci Scu sec sec Sed sel Sel sen ser Sex Sha she sho sid sig sil sim sin siz sla Sma sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spi spr squ sta sta sta sta ste ste ste Sto Str str str sub sub suc sun sup sup sup sup sur swa syn syn tab tar tek tem ter tes the the the the Tho thr tid tim Tis Too Tor tra tra Tra tra tra tri tri tru Tul tur two Typ ult un- und uni uni unk upp Urc utt val var vec vel ver vib vio vir vis voi vor wan wat wav wax wea Wei whi Wil win WN9 wor X-r yel you zer zod > >>
density profile farâpâl-e cagâli Fr.: profile de densité 1) A → profile representing the
→ density of a quantity. |
density wave mowj-e cagâli (#) Fr.: onde de densité A wave phenomenon in which the density fluctuations of a physical quantity propagates in a compressible medium. For example, the → spiral arms of a → galaxy are believed to be due to a density wave which results from the natural instability of the → galactic disk caused by its own gravitational force. A common example of a density wave concerns traffic flow. A slow-moving vehicle on a narrow two-lane road causes a high density of cars to pile up behind it. As it moves down the highway the "traffic density wave" moves slowly too. But the density wave of cars does not keep the same cars in it. Instead, the first cars leave the density wave when they pass the slow vehicle and continue on at a more normal speed and new ones are added as they approach the density wave from behind. Moreover, the speed with which the density wave moves is lower than the average speed of the traffic and that the density wave can persist well after its original cause is gone. See → density wave theory. |
density wave theory negare-ye mowj-e cagâli Fr.: théorie des ondes de densité One possible explanation for → spiral arms,
first put forward by B. Lindblad in about 1925 and developed later by
C.C. Lin and F. H. Shu. According to this theory, spiral arms are not material
structures, but regions of somewhat enhanced density, created by
→ density waves. Density waves are perturbations amplified by
the self-gravity of
the → galactic disk. The perturbation results from natural
non-asymmetry in the disk and enhanced by environmental processes, such as galaxy encounters.
Density waves rotate around the → galactic center and periodically
compress the disk material upon their passage. If the spiral arms were
rigid structures rotating like a pinwheel,
the → differential rotation
of the galaxy would wind up the arms completely in a relatively
short time (with respect to the age of the galaxy), → winding problem.
Inside the region defined by the → corotation radius,
density waves rotate more slowly than the galaxy's stars and gas; outside that
region they rotate faster. |
density-bounded H II region nâhiye-ye H II-ye cagâli karânmand Fr.: bornée par la densité An → H II region which lacks enough matter to absorb all → Lyman continuum photons of the → exciting star(s). In such an H II region a part of the ionizing photons escape into the → interstellar medium. See also → ionization-bounded H II region. |
deny niyârdan Fr.: nier To state that (something declared or believed to be true) is not true (Dictionary.com). M.E. denien, from O.Fr. denoiir "deny, repudiate, withhold," from L. denegare "to deny, reject, refuse," from → de- "away" + negare "refuse, say no," from Old L. nec "not," from PIE root *ne- "no, not." Niyârdan, literally "to bring (say) no," from ni-, variant of na→ not, → non-, → un-, + ârdan contraction of âvardan "to bring; to cause or produce," → production. |
dependent vâbasté (#) Fr.: dépendant 1) General: Determined or conditioned by something else. M.E. dependant, from M.Fr., pr.p. of dépendre, from L. dependere, from → de- + pendere "to hang, be suspended," PIE base *(s)pen(d)- "to pull, stretch." Vâbasté, from vâ-→ de- + basté p.p. of bastan "to bind, shut," from Mid.Pers. bastan/vastan "to bind, shut," Av./O.Pers. band- "to bind, fetter," banda- "band, tie," cf. Skt. bandh- "to bind, tie, fasten," PIE *bhendh- "to bind" (Ger. binden, E. bind). |
dependent variable vartande-ye vâbasté Fr.: variable dépendante Math.: A variable whose value depends on the value assigned to another value. For example, in the equation y = 2x, the value of y depends on that of x. See also → independent variable. |
dephase vâfâzidan Fr.: déphaser To make two signals out of phase. For example, to get one signal at its highest peak while the other signal is at its lowest peak; they will be 180 degrees out of phase. |
dephased vâfâzidé Fr.: déphasé Same as → out of phase. Past participle of → dephase. |
deplete tisâyidan Fr.: amenuiser, réduire To decrease markedly the supply or abundance of; exhaust; to cause → depletion. From L.L. depletionem "blood-letting," from L. deplere "to un-fill, to empty out," from → de- "off, away" + plere "to fill," from plenus "full," from PIE *ple- "to be full," PIE base *pelu- "full," cf. O.Pers. paru- "much, many," Av. parav-, pauru-, pouru-, par- "to fill," Mod.Pers. por "full," Skt. puru-, Gk. polus. por "full," Gk. polus, O.E. full "full," from P.Gmc. *fullaz, O.H.G. fol, Ger. voll, Goth. full. Tisâyidan, from Tabari tisâ "empty, naked, bare" + -idan infinitive suffix. Variants of tisâ in dialects and literary Pers.: Saraxsi, Lâsgardi, Sangesari tusâ "empty, naked," Aftari tussâ "empty," literary Pers. tohi "empty," Mid.Pers. tuhig, Av. taoš- "to become empty," pres. tusa-, caus. taošaya-, tusən "they lose their posture," Skt. tuccha-, tucchya- "empty," L. tesqua, tesca "deserted place," Russian tošcij "hollow;" PIE base *teus- "to empty." |
depletion tisâyeš Fr.: déplétion General: The act or process of depleting. The state of being depleted. Noun from → deplete |
depletion layer lâye-ye tisâyeš Fr.: couche de déplétion The region of a semiconductor in which the density of mobile carriers is too low to neutralize the fixed charge density of donors and acceptors. |
depletion time zamân-e tisâyeš Fr.: temps de déplétion The time it takes for a given → chemical species to be reduced below a significant level of → abundance in a → compound or → object. |
depolarization vâqotbeš (#) Fr.: dépolarisation Reducing or randomizing the polarization of an electromagnetic wave, by transmission through a non-homogeneous medium or a depolarizer. from → de- + → polarization. |
depopulate vâporinidan Fr.: dépuepler To remove or reduce the population of, as by destruction or expulsion (Dictionary.com). |
deport vâbartidan Fr.: déporter To expel forcibly a foreigner from a country; banish. |
deportation vâbarteš Fr.: déportation The action of deporting an alien from a country. |
deposit 1) lerd; 2) lerd andâxtan, lerd oftâdan, lerdidan Fr.: 1) dépôt, gisement, lie, tarte; 2) déposer, se déposer 1a) Something precipitated, delivered and left, thrown down, or accumulated,
as by a natural process. From L. depositus, p.p. of deponere "to lay aside, put down," from → de- "away" + ponere "to put," → position. Lerd "sediment, tartar of wine," probably a variant of dord "dregs, lees, sediment, tartar of wine." |
deposition vâneheš Fr.: dépôt The process by which water vapor changes directly to ice without first becoming a liquid. This is how snow forms in clouds, as well as frost and hoar frost on the ground. The opposite of deposition is → sublimation. → condensation. M.E., from O.Fr. deposition, from L. deposition- "putting aside, testimony, burial," from deposit(us) "laid down," p.p. of deponere "to put down," from → de- + ponere "to put, place." Vâneheš, from vâ-→ de- + neheš verbal noun of nehâdan "to put, place," Mid.Pers. nihâtan, O.Pers./Av. ni- "down; into," → ni-, + dā- "to put; to establish; to give," dadāiti "he gives," cf. Skt. dadâti "he gives," Gk. didomi "I give," L. do "I give;" PIE base *do- "to give." |
depredation vâcaveš Fr.: déprédation An act of attacking or plundering. |
<< < -es -iv -ti 21 a p abe abs abs aca acc acc acr act ada adh Adr aer AGB air Alf Alg all alp alt AM amo ana And ang ani ano Ant Ant apa apo app app Ara Arc ari Arr ash ass ast ast asy atm ato att aut ave axi Bab bal Bal bar bar bea Bek Bes bia Big bin bin bip biv bla bli blu Boh Bol Bos bou bra bri bro buo cal cal can cap car Car cat cat CCD Cen cen CH cha cha che Che chr cir cir cit cla clo clo clu Coa coe coh col col col com com com com com com com com Com con con con con con con con con con con con con Cop Cor cor cor cos cos cou cou Cow cre cri cro cry cur cya Cyg dan dar dat de- deb dec dec ded def deg del dem den dep des det dev dia dif dif dih dio Dir dis dis dis dis dis dis DO don dou dow dro dur dwa dyn Dys ear ebb ecl edg egg Ein Ela ele ele ele ele ell eme emp enc eng ent epi equ equ equ esc eth Eur Eve exa exc exe exi exp exp ext ext ext fac fal far fed Fer fer fie fin fir fis fla flo flu fol for for fou fra fre Fre fro fut G-t gal gal gam gas Gau Gem gen geo geo geo gia Gli Gol gra gra gra gra gre gri gui H I Hag hal har hat He- hea hel Hel her Hes hie hig his hom hor hot Hub Hug hur hyd hyd hyg hyp ice ide ima Ima imp imp inc inc ind ine inf inf inf ing inn ins ins int int int int int int int int inv Io ion iro isl iso iso Jac jet jud jur Kel Kep kil Klo Kui Lag lam Lap Lar lat law lea len lep Lib lig lim lin lin Lio lit loc LOF lon Lor low lum lun Lup Lyo mac mag mag mag mag mag mai man Mar mas mas mat Max mea mec Meg Mer Mer met met Met mic Mid Mil min Mir mit mod mod mol mon Mor mou mul mul mys nan Nat nau nec neo neu nev New NGC no nom non non nor not nuc nuc num nut obj obs obs occ ocu oft ome Oor ope opp opt opt orb ord ori ort osc out ove oxi pai pan par par par par pas pea pen per per per per Per per pha phi pho pho pho phy pio Pla pla pla pla Pla plu Poi pol pol pol poo pos pos pot pra pre pre pre pre pri pri pro pro pro pro pro Pro pro pse pul pur qua qua qua qua que rac rad rad rad rad rad rad ran rar ray rea rea rec rec red red ref ref reg rel rel rel ren res res res res ret rev Ric rig rin roc roo rot rot Rus Sac sal sat sca sca Sch sci Scu sec sec Sed sel Sel sen ser Sex Sha she sho sid sig sil sim sin siz sla Sma sno sof sol sol sol sol sou sou spa spa spe spe spe sph spi spi spr squ sta sta sta sta ste ste ste Sto Str str str sub sub suc sun sup sup sup sup sur swa syn syn tab tar tek tem ter tes the the the the Tho thr tid tim Tis Too Tor tra tra Tra tra tra tri tri tru Tul tur two Typ ult un- und uni uni unk upp Urc utt val var vec vel ver vib vio vir vis voi vor wan wat wav wax wea Wei whi Wil win WN9 wor X-r yel you zer zod > >>