positioning table
71oxidation–reduction reaction — ▪ chemical reaction Introduction also called redox reaction any chemical reaction in which the oxidation number of a participating chemical species changes. The term covers a large and diverse body of processes. Many oxidation– reduction… …
72tunnels 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 …
73Boston — This article is about the capital of Massachusetts. For other uses, see Boston (disambiguation). Boston   City   Clockwise: Skyline of Back Bay seen from the …
74Compass — This article is about the direction finding instrument used in navigation. For other uses, see Compass (disambiguation). A simple dry magnetic pocket compass …
75Billerica, Massachusetts —   Town   Billerica Public Library Nickname(s) …
761994 Group — Infobox Organization name = 1994 Group caption = formation = 1994 type = Association of UK universities headquarters = location = United Kingdom membership = 18 leader title = Chair of the Board leader name = Professor Steve Smith key people =… …
77Boiling water reactor — A boiling water reactor (BWR) is a type of nuclear reactor developed by the General Electric in the mid 1950s.Fact|date=April 2008 The BWR is characterized by two phase fluid flow (water and steam) in the upper part of the reactor core. See… …
78Exchangeable image file format — This article is about a format for storing metadata in image and audio files. For information about filename and directory structures of digital cameras, see Design rule for Camera File system. Filename extension .JPG, .TIF, .WAV Developed by… …
79M-209 — can also refer to a highway in the U.S. state of Michigan; see M 209 (Michigan highway) In cryptography, the M 209, designated CSP 1500 by the Navy (C 38 by the manufacturer) is a portable, mechanical cipher machine used by the US military… …
80Laser engraving — is the practice of using lasers to engrave or mark an object. The technique can be very technical and complex, and often a computer system is used to drive the movements of the laser head. Despite this complexity, very precise and clean… …
