Using spectral distribution of radiance temperature and relative emissivity for determination of the true temperature of opaque materials

2018 ◽  
Vol 25 (1) ◽  
pp. 133-144 ◽  
Author(s):  
S. P. Rusin
Keyword(s):  
Spectral Distribution ◽  
True Temperature ◽  
Radiance Temperature ◽  
Relative Emissivity

scholarly journals The effect of accommodation on heat conduction through gases

1934 ◽  
Vol 143 (850) ◽  
pp. 517-540 ◽  
Keyword(s):  
Thermal Conductivity ◽  
Solid Surfaces ◽  
True Temperature ◽  
Hot Wire ◽  
Absolute Value ◽  
Temperature Discontinuity ◽  
Double System ◽  
Wire Method ◽  
Gas Molecules

An experimental determination of the thermal conductivity of a gas necessarily involves a number of corrections which must either be determined or eliminated before an absolute value can be obtained. With the " hot-wire " method the inherent errors are: (1) the beat lost by radiation ; (2) the beat losses due to convection; (3) the temperature discontinuity between the gas and solid surfaces ; and (4) the fact that the interchange of energy between the gas molecules and the solid surfaces is not perfect. The true temperature attained by a molecule striking a bot surface always being less than the temperature of that surface. previous investigators using this method have applied a correction for the beat lost by radiation, determined by measuring the beat loss in the best obtainable vacuum ; while the convective beat loss has been eliminated, either by simply reducing the pressure or by using a double system of tubes. Both methods are debatable, for the first is very inaccurate, while the second necessarily complicates the experimental arrangement.

scholarly journals Experimental Determination of Scan-truncation Losses from Low-temperature (16 K) Single-crystal X-ray Measurements

1988 ◽  
Vol 41 (3) ◽  
pp. 503 ◽  
Author(s):  
Riccardo Destro
Keyword(s):  
Low Temperature ◽  
Single Crystal ◽  
Experimental Determination ◽  
Least Squares ◽  
Spectral Distribution ◽  
Experimental Measurements ◽  
Fourier Methods ◽  
X Ray ◽  
Least Squares Fitting

Model intensity profiles have been obtained for biscarbonyl[ 14]annulene by convoluting the Mo Ka spectral distribution with two functions derived from experimental measurements at 16(1) K, up to 26Mo = 110�, of a spherical crystal mounted on a four-circle diffractometer equipped with the Samson low-temperature apparatus. The process includes accurate measurement of the inherent background, treatment of the profiles by numerical Fourier methods, and least-squares fitting. Owing to the instrumental configuration of the diffractometer used in this investigation, the first step of the process has required a careful determination of the X dependence of the background, besides the usual 26 dependence. Truncation losses for the crystal under study, evaluated for several scan ranges, are far larger than usually assumed or predicted.

Theoretical Calculation of Background in X-Ray Spectrometry for the Determination of Some Heavy Trace Elements

1991 ◽  
Vol 35 (B) ◽  
pp. 755-756
Author(s):  
Jean-Jacques Gruffat
Keyword(s):  
Trace Elements ◽  
Theoretical Calculation ◽  
Spectral Distribution ◽  
Geological Samples ◽  
X Ray ◽  
Correct Calculation ◽  
The Continuum

AbstractThe Kulenkampff-Kramers formula giving the spectral distribution of the continuum as a function of wavelength allows a correct calculation of background under the peak. It is only necessary to measure two backgrounds, one on each side of the peak, The true background under the peak is given by multiplying them by adequate coefficients and adding them up. This method has been applied to the determination of low amounts of Ce, La, Ba and Cs in geological samples.

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