average core diameter
111Photonic-crystal fiber — (PCF) is a new class of optical fiber based on the properties of photonic crystals. Because of its ability to confine light in hollow cores or with confinement characteristics not possible in conventional optical fiber, PCF is now finding… …
112Globus Cassus — is an art project and book[1] by Swiss architect and artist Christian Waldvogel presenting a conceptual transformation of Planet Earth into a much bigger, hollow, artificial world with an ecosphere on its inner surface. It was the Swiss… …
113materials science — the study of the characteristics and uses of various materials, as glass, plastics, and metals. [1960 65] * * * Study of the properties of solid materials and how those properties are determined by the material s composition and structure, both… …
114nebula — nebular, adj. /neb yeuh leuh/, n., pl. nebulae / lee , luy /, nebulas. 1. Astron. a. Also called diffuse nebula. a cloud of interstellar gas and dust. Cf. dark nebula, emission nebula, reflection nebula …
115tunnels and underground excavations — ▪ engineering Introduction Great tunnels of the world Great tunnels of the worldhorizontal underground passageway produced by excavation or occasionally by nature s action in dissolving a soluble rock, such as limestone. A vertical opening …
116Outline of forestry — See also: Index of forestry articles The following outline is provided as an overview of and guide to forestry: Forestry – the art and science of managing forests, tree plantations, and related natural resources. Forest ecosystems have come to be …
117Nuclear fusion — Nuclear physics Radioactive decay Nuclear fission Nuclear fusion Classical dec …
118Supernova — This article is about the astronomical event. For other uses, see Supernova (disambiguation). Multiwavelength X ray, infrared, and optical compilation image of Kepler s supernova remnant, SN 1604. A supernova is a stellar explosion that is more… …
119Triton (moon) — Triton Voyager 2 photomosaic of Triton s sub Neptunian hemisphere. The bright, slightly pinkish, south polar cap at bottom is composed of nitrogen and methane ice and is streaked by dust deposits left by nitrogen gas geysers. The mostly darker… …
120Operation Crossroads — Coordinates: 11°36′N 165°30′E / 11.6°N 165.5°E / 11.6; 165.5 …
