I Intensity of light

Ig = intensity of light irradiating the sample I = intensity of light transmitted through the sample... 

A constant I intensity of light transmitted through the sample. 

For the mechanism of chemiluminescence in which the intensity of light emission I is proportional to the rate of oxidation w and, therefore, to the concentration of hydroperoxides, the following function of time f may be deduced ... 

Aa absorbance at wavelength A Iq intensity of incident light I intensity of transmitted light ex (molar) absorption coefficient at wavelength A c concentration d length of optical path within the cuvette. 

I0 is the intensity incident upon the sample and I is the intensity of light transmitted by the column of gas at 1 atm. pressure and 0°C. (STP) and Ax cm. long. The constant a is, therefore, proportional to the absorptivity. Experimentally, a is not precisely constant but should be defined in terms of concentration, temperature, medium, etc. 

From Rayleigh theory, the intensity of light scattered from each droplet or particle depends largely on its size and shape, and on the difference in refractive index between the particle and the medium. For a dispersion, each spherical droplet, bubble, or particle scatters unpolarized light having an intensity l[Pg.24]

An alternative to laser flash photolysis which is useful for studying opaque (but reflecting) samples, is diffuse reflectance spectroscopy [27]. This spectroscopic technique measures the ratio of the intensity of light reflected from the sample, I, to that reflected from a background or reference reflective surface, Iq. In time-resolved... 

This relates the detector signal to the intensity (I) of light produced, the efficiency of light collection (G), and the PMT sensitivity (A). The intensity of light produced is expressed as the product of the NO concentration, the flow rate, and a series of fractions (fraction of N02 formed in the excited state, fraction of NO2 decaying radiatively, and the fraction of NO-O3 reaction occurring within view of the detector). 

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