- twofold screw axis
- nCRYSTALL eje binario de inversión m
English-Spanish technical dictionary. - London, © Routledge. 1997.
English-Spanish technical dictionary. - London, © Routledge. 1997.
Space group — In mathematics and geometry, a space group is a symmetry group, usually for three dimensions, that divides space into discrete repeatable domains. In three dimensions, there are 219 unique types, or counted as 230 if chiral copies are considered… … Wikipedia
Symmetry — For other uses, see Symmetry (disambiguation) … Wikipedia
Mendipite — from the Torr Works Quarry (Merehead Quarry), Cranmore, Somerset, England. Specimen size 2 cm General Category Halides … Wikipedia
Transmission electron microscopy — A TEM image of the polio virus. The polio virus is 30 nm in size.[1] Transmission electron microscopy (TEM) is a microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it… … Wikipedia
Crystal structure — In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice… … Wikipedia
Steam locomotive — A steam locomotive is a locomotive powered by steam. The term usually refers to its use on railways, but can also refer to a road locomotive such as a traction engine or steamroller.Steam locomotives dominated rail traction from the mid 19th… … Wikipedia