Yellow light

The color of the emitted light depends on what type of gas is present. For example, sodium atoms glow with a yellow light (as in the familiar yellow street lights), and neon glow with a dark red light (as in the familiar neon lights). 

C is the concentration of limiting reactant in mol/L, c is the chemiluminescence quantum yield in ein/mol, and P is a photopic factor that is determined by the sensitivity of the human eye to the spectral distribution of the light. Because the human eye is most responsive to yellow light, where the photopic factor for a yellow fluorescer such as fluorescein can be as high as 0.85, blue or red formulations have inherently lower light capacities. 

The theoretical limit of light capacity has been estimated for an ideal reaction that provides yellow light with a photopic factor of 0.85 in a quantum yield of one at 5 Af concentration as 173,000 (Im-h)/L, equivalent to the light output of a 40-W bulb burning continuously for two weeks (237). The most efficient formulation available, based on oxaUc ester chemiluminescence, produces about 0.5% of that limit, with a light capacity of 880 (Im-h)/L (237). 

Owing to the light and air sensitivity of the carotenoids and retinoids, sample handling is a critical issue. It is recommended to conduct extraction of these materials with peroxide-free solvents, to store biological samples at —70° C under argon and in the dark, to perform the analysis under yellow light, and to use reference compounds of high purity (57). 

To express optical rotations in a meaningful way so that comparisons can be made, we have to choose standard conditions. The specific rotation, [a ]D, of a compound is defined as the observed rotation when light of 589.6 nanometer (nm 1 nm = 10-9 m) wavelength is used with a sample pathlength / of 1 decimeter (dm 1 dm = 10 cm) and a sample concentration C of 1 g/mL. (Light of 589.6 nm, the so-called sodium d line, is the yellow light emitted from common sodium lamps.)... 

Daubner, S. C., Astorga, A. M., Leisman, G. B., and Balwin, T. O. (1987). Yellow light emission of Vibrio barveyi strain Y-l purification and characterization of the energy-accepting yellow fluorescent protein. Proc. Natl. Acad. Sci. USA 84 8912-8916. 

Ruby, E. G., and Nealson, K. H. (1977). A luminous bacterium which emits yellow light. Science 196 432-434. 

With its varnished wood ceiling, La Bottega, scarred and mirrored and yellow-lighted, is like drinking inside an antiquated jukebox, one in Havana diat no one has the money to replace. 

In neutral conditions, the molecule has no charge. It absorbs yellow light and appears purple. Notice all the alternating single and double bonds. 

Self-Test 1.4A What is the energy of a photon of yellow light of frequency 5.2 X 1014 Hz ... 

A discharge lamp rated with a power of 25 W (1 W = 1 J s-1) emits yellow light of wavelength 580 nm. How many photons of yellow light does the lamp generate in 1.0 s ... 

This result means that, when you turn on the lamp, it generates about 1020 photons of yellow light each second. As predicted, this number is very large. 

Sodium vapor lamps, used for public lighting, emit yellow light of wavelength 589 nm. How much energy is emitted by... 

Pentaphenylborol-tricarbonyliron, e.g., is prepared from Fc2(CO)9 and the borole in toluene at 45-50°C. Chromatography on AI2O3 yields the complex as yellow light-and air-sensitive crystals . ... 

A sodium-vapor street lamp emits yellow light at wavelength A — 589 nm. What is the energy change for a sodium atom involved in this emission How much energy is released per mole of sodium atoms ... 

Sodium vapor lamps emit yellow light. 

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