absolute 1 pure, unmixed; e.g. absolute alcohol. 2 not relative; e.g. absolute configuration. 3 describing a measurement defined in fundamental units of mass, length, and time that does not depend on the characteristics of the measuring apparatus; e.g. absolute temperature.
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adiabatic demagnetization
A technique for cooling a paramagnetic salt, such as potassium chrome alum, to a temperature near absolute zero. The salt is placed between the poles of an electromagnet and the heat produced during magnetization is removed by liquid helium. The salt is then isolated thermally from the surroundings and the field is switched off; the salt is demagnetized adiabatically and …
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A way of denoting the absolute structure of an optical isomer . Two conventions are in use: The D-L convention relates the structure of the molecule to some reference molecule. In the case of sugars and similar compounds, the dextrorotatory form of glyceraldehyde (HOCH2CH(OH)CHO , 2,3-dihydroxypropanal) was used. The rule is as follows. Write the structure of this molecule down …
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1. Not dependent on or relative to anything else, e.g. absolute zero. 2. Denoting a temperature measured on an absolute scale, a scale of temperature based on absolute zero. The usual absolute scale now is that of thermodynamic temperature; its unit, the kelvin, was formerly called the degree absolute (0A) and is the same size as the degree Celsius. In …
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