Search results
Results From The WOW.Com Content Network
The D 1 and D 2 lines form a pair known as the "sodium doublet", the centre wavelength of which (589.29 nm) is given the designation letter "D". This historical designation for this line has stuck and is given to all the transitions between the ground state and the first excited state of the other alkali atoms as well.
The rotation is reported using degrees, and no units of concentration are given (it is assumed to be g/100mL). The sign of the rotation (+ or −) is always given. If the wavelength of the light used is 589 nanometer (the sodium D line), the symbol “D” is used. If the temperature is omitted, it is assumed to be at standard room temperature ...
A low-pressure sodium lamp running at full brightness An unlit 35 W LPS/SOX lamp LPS lamp warming up A running 35 W LPS/SOX lamp Spectrum of a low-pressure sodium lamp. The intense yellow band is the atomic sodium D-line emission, comprising about 90% of the visible light emission for this lamp type. Two Honda Fits under low-pressure sodium ...
Standard refractive index measurements are taken at the "yellow doublet" sodium D line, with a wavelength (λ) of 589 nanometers. There are also weaker dependencies on temperature , pressure / stress , etc., as well on precise material compositions (presence of dopants , etc.); for many materials and typical conditions, however, these ...
A reference wavelength of 589.3 nm (the sodium D line) is most often used. Though RI is a dimensionless quantity, it is typically reported as nD20 (or n 20 D ), where the "n" represents refractive index, the "D" denotes the wavelength, and the 20 denotes the reference temperature. Therefore, the refractive index of water at 20 degrees Celsius ...
The specific rotation [] is a physical property and defined as the optical rotation α at a path length l of 1 dm, a concentration c of 10 g/L, a temperature T (usually 20 °C) and a light wavelength λ (usually sodium D line at 589.3 nm): [4]
Particular light frequencies give rise to sharply defined bands on the scale which can be thought of as fingerprints. For example, the element sodium has a very characteristic double yellow band known as the Sodium D-lines at 588.9950 and 589.5924 nanometers, the color of which will be familiar to anyone who has seen a low pressure sodium vapor ...
Figure 3. Formation of fringes in a Michelson interferometer This photo shows the fringe pattern formed by the Michelson interferometer, using monochromatic light (sodium D lines). As shown in Fig. 3a and 3b, the observer has a direct view of mirror M 1 seen through the beam splitter, and sees a reflected image M' 2 of mirror M 2.