base ambient temperature
21Oxy-fuel welding and cutting — Oxyacetylene redirects here. For the song, see Cubanate. Side of metal, cut by oxygen propane cutting torch …
22petroleum refining — Introduction conversion of crude oil into useful products. History Distillation of kerosene and naphtha The refining of crude petroleum owes its origin to the successful drilling of the first oil well in Titusville, Pa., in 1859. Prior to… …
23Polymerase chain reaction — PCR redirects here. For other uses, see PCR (disambiguation). A strip of eight PCR tubes, each containing a 100 μl reaction mixture The polymerase chain reaction (PCR) is a scientific technique in molecular biology to amplify a single or a… …
24Stirling engine — Alpha type Stirling engine. There are two cylinders. The expansion cylinder (red) is maintained at a high temperature while the compression cylinder (blue) is cooled. The passage between the two cylinders contains the regenerator …
25Fluorescent lamp — A fluorescent lamp or fluorescent tube is a gas discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light.Unlike… …
26Motor oil — For the TV documentary focused on the Edmonton Oilers of the National Hockey League, see Oil Change (TV Series). Motor oil sample Motor oil or engine oil is an oil used for lubrication of various internal combustion engines. The main function is… …
27Properties of water — H2O and HOH redirect here. For other uses, see H2O (disambiguation) and HOH (disambiguation). This article is about the physical and chemical properties of pure water. For general discussion and its distribution and importance in life, see Water …
28Second — This article is about the unit of time. For other uses, see Second (disambiguation). A light flashing approximately once per second. The second (SI unit symbol: s; informal abbreviation: sec) is a unit of measurement of time, and is the… …
29Pendulum — This article is about pendulums. For other uses, see Pendulum (disambiguation). Simple gravity pendulum model assumes no friction or air resistance …
30relaxation phenomenon — ▪ physics and chemistry Introduction in physics and chemistry, an effect related to the delay between the application of an external stress to a system that is, to an aggregation of matter and its response. It may occur in nuclear, atomic,… …
