Damage may be a result of the direct effects of alcohol on the brain or may result indirectly, from a poor general health status or from severe liver disease. For example, thiamine deficiency is a common occurrence in people with alcoholism and results from poor overall nutrition.
In the case of a longitudinal wave, a wavelength measurement is made by measuring the distance from a compression to the next compression or from a rarefaction to the next rarefaction. On the diagram above, the distance from point A to point C or from point B to point D would be representative of the wavelength.
In the SI, the. angle of optical rotation is expressed in radians (rad). The optical rotation is measured on a layer of suitable thickness (optical path length. l. ) at the wavelength Î». and temperature T specified in the monograph. A typical optical path length is 100 mm, the most common. wavelength is 589 nm (Sodium D-Line), while the reference temperature is usually between 20-25 Â°C.