step-by-step excitation of atom
51radioactivity — /ray dee oh ak tiv i tee/, n. Physics, Chem. the phenomenon, exhibited by and being a property of certain elements, of spontaneously emitting radiation resulting from changes in the nuclei of atoms of the element. Also called activity. [1895… …
52Hydroxyl radical — IUPAC name Hydroxyl radical …
53Nuclear structure — Physics portal This page is an adapted translation of the corresponding fr:Structure nucléaire As will be noted, there remain void paragraphs, as on the original (which provides no sources). Competent Wikipedians are welcom …
54Semiconductor — Citations missing|date=March 2008A semiconductor is a solid material that has electrical conductivity in between a conductor and an insulator; it can vary over that wide range either permanently or dynamically. [. They are used in many… …
55Thin-film deposition — is any technique for depositing a thin film of material onto a substrate or onto previously deposited layers. Thin is a relative term, but most deposition techniques allow layer thickness to be controlled within a few tens of nanometers, and some …
56Membrane potential — Differences in concentration of ions on opposite sides of a cellular membrane lead to a voltage called the membrane potential. Many ions have a concentration gradient across the membrane, including potassium (K+), which is at a high inside and a… …
57Wikipedia:Featured article candidates — Here, we determine which articles are to be featured articles (FAs). FAs exemplify Wikipedia s very best work and satisfy the FA criteria. All editors are welcome to review nominations; please see the review FAQ. Before nominating an article,… …
58Work function — In solid state physics, the work function is the minimum energy (usually measured in electron volts) needed to remove an electron from a solid to a point immediately outside the solid surface (or energy needed to move an electron from the Fermi… …
59Type II supernova — The expanding remnant of SN 1987A, a Type II P supernova in the Large Magellanic Cloud. NASA image. A Type II supernova (plural: supernovae) results from the rapid collapse and violent explosion of a massive star. A star must have at least 9… …
60Di-pi-methane rearrangement — The di pi methane rearrangement is a photochemical reaction of a molecular entity comprising two π systems, separated by a saturated carbon atom (a 1,4 diene or an allyl substituted aromatic analog), to form an ene (or aryl ) substituted… …
