The science and technology of producing and exploiting structures and systems at dimensions of roughly 1 to 100 → nanometers, that is those of single atoms and molecules. Materials with such minute structures possess mechanical, optical, chemical, magnetic or electronic properties not found in ordinary materials.
Naos (ζ Puppis)
A bright, blue star of V = 2.25 in the constellation → Puppis. It is a hot → supergiant of type O5, with a → surface temperature of 42,000 K, lying 1,400 → light-years away. Naos is one of the rarest → O-type stars visible to the → naked eye.
Naos, from Gk. naos "ship," since it used to be the Zeta star of Argo Navis (Jason's vessel Argos) before becoming Zeta in Puppis.
logâritm-e Napieri (#)
Fr.: logarithme népérien
Same as the → natural logarithm.
After John Laird Napier (1550-1617), the Scottish mathematician who invented logarithm; → logarithm.
Of little breadth or → width.
M.E., from O.E. nearu; cf. O.S. naru "narrow," Du. naar "unpleasant;" akin to Ger. Narbe "scar," literally, "narrow mark."
Bârik, from Mid.Pers. bârîk "narrow," from O.Iranian *bāra-ya-ka-, from stem *bāra- "to cut;" cf. Av. bāra- "edge, blade," in tiži-bāra- "sharp-edged," from brī- "to cut, shave, shear;" cf. Skt. bhrī- "to hurt, injure," bhrinanti "they hurt;" O.C.S. briti "to shave;" PIE base *bhrē- "to cut, pierce."
bând-e bârik (#), bârik-bând (#)
Fr.: bande étroite
Optics: Of a filter, same as → interference filter.
šidsanji-ye bârik bând
Fr.: photométrie à bande étroite
Photometry using narrow-band filters to isolate a particular spectroscopic line or molecular band.
Fr.: région à raies étroites
A lunar → impact crater that is located in the southern part of the Moon's near side. Latitude: 41.0°S, longitude: 0.2°E, diameter: 52 km, depth: 3.35 km.
Named after the Iranian mathematician and astronomer Nasireddin Tusi (1201-1274), → Nasireddin couple.
Fr.: couple de Nasireddin
A theorem put forward by the 13th century Persian mathematician and astronomer Nasireddin Tusi to generate linear motion from a combination of circular motions, and thus improve the geocentric model of Ptolemy. A circle of radius R rotates inside a circle of radius 2R. The smaller circle rotates at twice the speed of the larger one and in opposite direction. The initial tangent point will travel in linear motion back and forth along the diameter of the larger circle. A particular case of → hypocycloid curves.
Named for Nasireddin Tusi (1201-1274), director of Marâgha observatory who created the Ilkhani zij; → couple.
kânun-e Nasmyth (#)
Fr.: foyer Nasmyth
In an altazimuth-mounted telescope, a focal point to one side of the tube, created by placing a third deflecting mirror in the optical path. This extra mirror directs the beam along the altitude axis, and through a hole in the supporting trunnions. Nasmyth focus has the advantage of remaining at a fixed position relative to the telescope wherever the instrument is pointed. Moreover, bulky or heavy instruments can be mounted there on a permanent platform, which rotates only in azimuth.
Named after the inventor James Nasmyth (1808-1890), who first used it in the 19-th century.
Nation, from O.Fr. nacion, from L. nationem (nom. natio) "nation, stock, race," literally "that which has been born," from natus, p.p. of nasci "to be born;" cognate with Pers. zâdan, → generate.
Nafân, from Av. nāfaēna- "family," hama.nāfaēna- "of the same family," related to nāfa- "near relationship, family, navel," napāt- "grandson" (Mod.Pers. navé "grandson"); cf. Mid.Pers. nâf "family," nâfag "navel," naft "descendant, " Parthian nap "family" (Mod.Pers. nâf "navel"); Sogd. nâf "country;" Sorani Kurd. natawa (Kurmanji Kurd. netewe) "family, race, nation," from *nafata (with metathesis); cf. Skt. nábhi- "nave, navel, central part; home, origin;" Gk. anepsios "cousin, sister's son;" L. nepos "grandchild; descendant;" O.Lithuanian neputis "grandson; nephew;" O.H.G. nabalo "navel;" Ger. Nabel "navel;" O.E. nefa "grandson; descendant;" + -ân suffix denoting family relationship, as in Bâbakân "family of Bâbak."
Of, involving, or relating to a nation as a whole. → National Aeronautics and Space Administration (NASA).
National Aeronautics and Space Administration (NASA)
Sâzmân-e Fazânavardi-ye Âmrikâ
Fr.: NASA, Administration nationale de l'aéronautique et de l'espace
A federal agency of the United States government founded in 1958 for civil aeronautical research and space exploration, superseding the National Advisory Committee for Aeronautics (NACA). Its goals include improving human understanding of the universe, the solar system, and Earth and establishing a permanent human presence in space. NASA is headquarted at Washington, D.C., and operates several research, development, and test facilities, as follows alphabetically: 1) Ames Research Center; 2) Dryden Flight Research Facility at Edwards, California, used for flight testing and as a landing site for the Space Shuttle; 3) Glenn Research Center at Cleveland, Ohio, concerned with aircraft and rocket propulsion; 4) Goddard Space Flight Center; 5) Jet Propulsion Laboratory; 6) Johnson Space center; 7) Kennedy Space Center; 8) Langley Research Center at Hampton, Virginia, which carries out research in aeronautics and space technology; 9) Marshall Space Flight Center; 10) the Space Telescope Science Institute; 11) Stennis Space Center, near Bay St Louis, Mississippi, for testing rocket engines; and 12) Wallops Flight Facility on Wallops Island, Virginia, which manages NASA's sounding rocket and scientific balloon programs.
→ national; → aeronautics; → space; administration, verbal noun of administer, from M.E. amynistre, from O.Fr. aministrer, from L. administrare "to serve, carry out, manage," from → ad- "to" + ministrare "to serve," from minister "servant, priest's assistant," from minus, minor "less," hence "subordinate," + comparative suffix *-teros.
Loyalty and devotion to a nation; especially: a sense of national consciousness exalting one nation above all others and placing primary emphasis on promotion of its culture and interests as opposed to those of other nations or supranational groups (Merriam-Webster.com).
1) National status; specifically: a legal relationship involving
allegiance on the part of an individual and usually protection on the
part of the state b : membership in a particular nation.
The transfer of a major branch of industry or commerce from private to state ownership or control (OxfordDictionaries.com)
1) To bring under the ownership or control of a nation, as industries and land (Dictionary.com).
Occurring in nature; not artificially prepared. → nature.
Adj. of → nature.
Fr.: fréquence naturelle
Any frequency of small-amplitude oscillation for a system with a position of stable equilibrium and in the absence of external forces. In other words, the frequency of → free oscillation. Also called characteristic frequency.
Fr.: histoire naturelle
The → sciences, as → botany, → mineralogy, or → zoology, dealing with the study of all objects in → nature: used especially in reference to the beginnings of these sciences in former times (Dictionary.com).