| flame ionization | Pyrolysis of organic compounds at the temperature of a hydrogen-air flame to produce ionic intermediates which can be collected and the resulting ion current measured by gas chromatography. (12 Dec 1998) |
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| spectrometry, mass, matrix-assisted laser desorption-ionization | A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis. (12 Dec 1998) |
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| ionization | <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) |
| ionization chamber | A chamber for detecting ionization of the enclosed gas; used for determining intensity of ionizing radiation. (05 Mar 2000) |
| flame | 1. A stream of burning vapor or gas, emitting light and heat; darting or streaming fire; a blaze; a fire. 2. Burning zeal or passion; elevated and noble enthusiasm; glowing imagination; passionate excitement or anger. "In a flame of zeal severe." "Where flames refin'd in breasts seraphic glow." (Pope) "Smit with the love of sister arts we came, And met congenial, mingling flame with flame." (Pope) 3. Ardor of affection; the passion of love. 4. A person beloved; a sweetheart. Synonym: Blaze, brightness, ardor. See Blaze. Flame bridge, a bridge wall. See Bridge. Flame colour, brilliant orange or yellow. Flame engine, an early name for the gas engine. Flame manometer, an instrument, invented by Koenig, to obtain graphic representation of the action of the human vocal organs. See Manometer. <chemistry> Flame reaction, a method of testing for the presence of certain elements by the characteristic colour imparted to a flame; as, sodium colours a flame yellow, potassium violet, lithium crimson, boracic acid green, etc. Cf. Spectrum analysis, under Spectrum. <botany> Flame tree, a tree with showy scarlet flowers, as the Rhododendron arboreum in India, and the Brachychiton acerifolium of Australia. Origin: OE. Flame, flaume, flaumbe, OF. Flame, flambe, F. Flamme, fr. L. Flamma, fr. Flamma, fr. Flagrare to burn. See Flagrant, and cf. Flamneau, Flamingo. Source: Websters Dictionary (01 Mar 1998) |
| flame arc | An arc between two impregnated electrodes that causes volatilization of the core with resultant flame. (05 Mar 2000) |
| flame emission spectrophotometry | Determination of the concentration of an element by measurement of light emitted when the element is excited by energy in the form of heat. (05 Mar 2000) |
| flame figure | A small area of dermal or subcutaneous necrosis with intense eosinophil staining of collagen bundles; seen in the lesions of Well's syndrome. (05 Mar 2000) |
| flame ionisation detector | <apparatus> A piece of equipment used in gas chromatography that uses a flame to decompose the neutral solute molecules into charged particles, then measures any changes in conductivity. (09 Oct 1997) |
| flame retardants | Materials applied to fabrics, bedding, furniture, plastics, etc. To retard their burning; many may leach out and cause allergies or other harm. (12 Dec 1998) |
| flame spots | Haemorrhagic areas occurring in the nerve fibre layer of the retina. (05 Mar 2000) |