Wavelength interval

The correction factor C still applies. Spectral data for water vapor, tabulated for 371 wavelength intervals from 1 to 40 Im, are also available [Ferriso, Ludwig, and Thompson, J. Quant. Spectm.s. Radiat. Tran.sfer, 6, 241-273 (1966)]. The principal emission is in bands at about 2.55 to 2.84, 5.6 to 7.6, and 12 to 25 jlm. 

The more nearly the wavelength interval — X approaches zero, the more nearly... 

The solar spectrum corresponds roughly to the radiation of a black body at the temperature 5750 K. If we denote the photon flux in the wavelength interval from A to (A 4- dA) (in photons/m2 s) as /(A), the total solar power flux (in W/m2) is given as ... 

The use of these formulas involves subdividing the visible spectrum into L (at least 16) intervals. The subscript n labels these wavelength intervals. / characterizes the intensity of illumination in interval n, while Rn is the average reflection factor for this interval. The quantities xn, yn, and zn are found in tables (contained in standards) for typical illumination conditions and for an observer with normal vision. If two colored samples are of the same color, their X, Y, and Z values are equal pairwise. If two objects have the same color under a given illumination, this... 

FIGURE 7.1 NIR spectra from different fermentations of rye with yeast. The seven spectra have been measured in reflection mode in opaque mashes. Wavelength interval is 1100-2300 nm the number of data points is 241. The samples differ in the ethanol contents (62.2-84.1 g/L). 

Finally, mention should be made of the new spectrophotometers based on an array of detectors (see Chapter 2). The operation of these spectrophotometers is much simpler, as they are not monochromators, each detector in the array being used to record a wavelength interval. However, these monochromators suffer from the drawback of poor spectral resolution. 

Results of an experimental program in which aluminum particles were burned with steam and mixtures of oxygen and argon in small-scale atmospheric dump combustor are presented. Measurements of combustion temperature, radiation intensity in the wavelength interval from 400 to 800 nm, and combustion products particle size distribution and composition were made. A combustion temperature of about 2900 K was measured for combustion of aluminum particles with a mixture of 20%(wt.) O2 and 80%(wt.) Ar, while a combustion temperature of about 2500 K was measured for combustion of aluminum particles with steam. Combustion efficiency for aluminum particles with a mean size of 17 yum burned in steam with O/F) / 0/F)st 1-10 and with residence time after ignition estimated at 22 ms was about 95%. A Monte Carlo numerical method was used to estimate the radiant heat loss rates from the combustion products, based on the measured radiation intensities and combustion temperatures. A peak heat loss rate of 9.5 W/cm was calculated for the 02/Ar oxidizer case, while a peak heat loss rate of 4.8 W/cm was calculated for the H2O oxidizer case. 

Table 3.10 shows the calculated percentage increase in the actinic flux at the earth s surface for an elevation of 1.5 km and atmospheric pressure of 0.84 atm (corresponding approximately to Denver) as a function of zenith angle for four wavelength intervals. In this calculation, it was assumed that the vertical 03 and particle... 

TABLE 3.7 Actinic Flux Values F( A) at the Earth s Surface as a Function of Wavelength Interval and Solar Zenith Angle within Specific Wavelength Intervals for Best Estimate Surface Albedo Calculated by Madronich (1998) ... 

Wavelength interval Solar zenith an8le (degrees)... 

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