absorptance
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GC: n

CT: An expression for the thermal efficiency of a surface used as a receiver for spacecraft solar-power generation is derived in terms of the solar absorptance, hemispherical emittance, and concentration ratio. Experimental equipment is described in which direct measurements may be made up to 1000°C by using a carbon-arc-image furnace to simulate the sun. Emittance and absorptance data are presented on six polished metals and four plasma flame sprayed coatings from 200 to 800°C. It is shown that thermal conversion efficiencies as high as 40 percent at 800°C can be realized with refractory coatings and with a solar radiation concentration ratio of 50 or 6.9 watts per square centimeter.

S: SDir – http://www.sciencedirect.com/science/article/pii/0038092X64900039 (last access: 6 January 2016)

N: 1. First use: about 1931. Origin: “absorption” (1590s, from Latin absorptionem (nominative absorptio), noun of action from past participle stem of absorbere “swallow up”) + “-ance” (Middle English, from Anglo-French, from Latin -antia, from -ant-, -ans -ant + -ia -y. Full definition of -ance: 1. action or process : instance of an action or process . 2. quality or state : instance of a quality or state . 3. amount or degree ).

2. The ratio of absorbed to incident solar radiation.

3. In general, the value of the absorptance depends upon the mode of irradiation, the spectral composition and the state of polarization of the incident radiation.

S: 1. Etymonline – http://www.etymonline.com/index.php?term=absorption (last access: 6 January 2016); MW – http://www.merriam-webster.com/dictionary/absorptance; http://www.merriam-webster.com/dictionary/-ance (last access: 6 January 2016). 2. TERMIUM PLUS – http://goo.gl/kE6foH (last access: 6 January 2016). 3. GDT – http://www.granddictionnaire.com/ficheOqlf.aspx?Id_Fiche=8401362 (last access: last access: 6 January 2016).

SYN: absorption factor

S: WIKIL – http://www.wikilengua.org/index.php/Terminesp:absortancia (last access: 2 June 2019)

CR: solar energy