Photometers, definition

The simplest case of a reactor is a cuvette, such as that in a photometer. From the Michaelis-Menten equation and the equation for the batch reactor [Eqs. (5.11) and (5.12)], respectively, as well as the definition for the degree of conversion % for the simple reaction S —> P, x = 1 - [S]/[S0] = [P]/[S0], the integrated equation (5.15) for an enzyme reaction following a Michaelis-Menten law in a batch reactor is obtained. 

With this experiment, Land and McCann vividly demonstrated that the perceived color of an object does not depend on the light reflected by the object. The perceived color depends on the reflectance, which specifies how much of the incident light is reflected. The reflectance determines the color of the object. The reflected light is essentially proportional to the product of the irradiance (see Table B.l for a definition) and the reflectance of the object. A human observer is somehow able to derive the reflectances for the objects in view regardless of the illuminant used. In contrast, a digital or an analog camera can do no more than the telescopic photometer can. It only measures the reflected light. In order... 

By definition, photometers do not respond to radiation in the infrared or the ultraviolet (Fig. 4-4a). They are light meters in the sense that they mimic human vision that is, they respond to photons in the visible region, similar to the light meter on a camera. A candle is a unit of luminous intensity, originally based on a standard candle or lamp. The current international unit is called a candela (sometimes still referred to as a candle ), which was previously defined as the total light intensity of 1.67 mm2 of a blackbody radiator (one that radiates maximally) at the melting temperature of pure platinum (2042 K). In 1979 the candela was redefined as the luminous intensity of a monochromatic source with a frequency of 5.40 x 1014 cycles s-1 (A, of 555 nm) emitting 0.01840 Js-1 or 0.01840 W (1.464 mW steradian-1, where W is the abbreviation for watt and steradian... 

The definition team for the infrared photometer consists of R. Hall, D. Kleinmann and G. Neugebauer. As a first generation experiment the team proposes a simple filter wheel photometer which works from 1 p to 1 mm. A spectrometer with a spectral resolution of 3 x 10 is proposed for a second generation... 

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