الرئيسية » أرشيف الوسم : absolute

أرشيف الوسم : absolute

absolute

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 …

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absolute configuration

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 …

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absolute

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) …

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