
1) Composition by Edgard Varèse 2) Condition 3) Ionization 4) Status 
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1) Ionization 
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https://www.crosswordclues.com/clue/ionisation
[Varèse]  Ionisation (1929–1931) is a musical composition by Edgard Varèse written for thirteen percussionists, the first concert hall composition for percussion ensemble alone (although Alexander Tcherepnin had composed an entire movement for percussion alone in his Symphony No. 1 from 1927) . The premiere was at Steinway Hall, on March...
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http://en.wikipedia.org/wiki/Ionisation_(Varèse)

The process by which gas molecules are converted into positively and negatively charged particles called ions. This process occurs when an arc is struck between an electrode and the workpiece.
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(from the article `instrumentation`) ...music that is subservient to the brass or woodwinds. Percussion instruments greatly increased in importance and have continued to do so. In 1931, ...
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http://www.britannica.com/eb/a-z/i/37

The production of ions when an atom or group of atoms acquires or loses an electric charge.  Making them positive or negative ions.  High voltage conductors produce ionisation of the air surrounding the conductor and produce ions.  There is some speculation that this mechanism could be capable of transferring toxic elements. 
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The process by which a neutral atom or molecule acquires or loses an electric charge. The production of ions.
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<chemistry, radiobiology> Any process by which a neutral atom gains or loses electrons, thus acquiring a net charge, as the dissociation of a substance in solution into ions or ion production by the passage of radioactive particles. ... High temperatures, electrical discharges or nuclear radiations can cause ionisation. ... (16 Dec 1997) ... ...
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Dissociation of substances in water to form atoms or groups of atoms carrying an electric charge.
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Ionisation is the process where by an Atom or molecule gains or looses an Electron and thus becomes an Ion . Ionising Radiation has sufficient energy to be able to ionise atoms and molecules and thus produce ions.
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http://www.ionactive.co.uk/glossary_atoz.html?s=az&t=i

An atom or molecule is said to be ionised when it has gained or lost one or more electrons. If an atom or molecule gains an electron, it is negatively charged (see anion*); losing an electron makes it positive (see cation*).
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