A phosphorescent substance which emits light when excited by radiation, as on the scope of a cathode-ray tube.
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COMPOUND
(1) chemically speaking, a distinct substance formed by the combination of two or more elements in definite proportions by weight and possessing physical and chemical properties different from those of the combining elements. (2) in petroleum processing, generally connotes fatty oils and similar materials foreign to petroleum added to lubricants to impart special properties.
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AIR
A substance containing by volume approximately 78 - 79% nitrogen; 20.95% oxygen, 0.94% argon, traces of carbon dioxide, helium, etc.
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EMISSION SPECTROMETER
Works on the basis that atoms of metallic and other particular elements emit light at characteristic wavelengths when they are excited in a flame, arc, or spark. Excited light is directed through an entrance slit in the spectrometer. This light penetrates the slit, falls on a grate, and is dispersed and reflected. The spectrometer is calibrated by a series of standard samples containing known amounts of the elements of interest. By exciting these standard samples, an analytical curve can be established which gives the relationship between the light intensity and its concentration in the fluid.
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GROUP OCCULTING LIGHT
An occulting light in which the occultations are combined in groups, each group including the same number of occultations, and in which the groups are repeated at regular intervals. The intervals of light separating the occultations within each group are of equal duration and this duration is clearly shorter than the duration of the interval of light between two successive groups.
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HAND LEAD
A light sounding lead (7 to 14 pounds), usually having a line of not more than 25 fathoms
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GROUP QUICK LIGHT
A quick flashing light in which a specified group of flashes is regularly repeated
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ACIDIC
The reaction of a substance with water resulting in an increase in concentration of hydrogen ions in solution (see acid).
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FLUID
A substance readily assuming the shape of the container in which it is placed; e.g. oil, gas, water or mixtures of these. A general classification including liquids and gases.
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CATALYST
A substance which speeds a chemical action without undergoing a chemical change itself during the process. Now used in catalytic converters to control amount of unburned hydrocarbons and CO in automobile exhaust.
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FLUID OPACITY
Related to the ability of a fluid to pass light.
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