emissivity


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e·mis·siv·i·ty

(ē'mi-siv'i-tē),
The giving off of heat rays; a perfect "black body" has an emissivity of 1, a highly polished metallic surface may have an emissivity as low as 0.02.

emissivity

(ĕm″ĭ-sĭv′ĭ-tē)
The ability of a substance or surface to emit radiant energy.
References in periodicals archive ?
To achieve the same temperature as the first measuring point (thermal equilibrium) and determine the specific emissivity factor, [epsilon] of the rectangle is modified until the two temperatures are equal [14].
In the case where the oxide layer is present on the surface of the metal, the emissivity is a combined contribution of the transparent layer and metal, which includes thickness of the oxide layer.
In Section 3, the method for atmospheric correction and the method for Temperature and Emissivity Separation are briefly described.
The NLO contribution to the neutrino emissivity is [33,35,41]
The IR emissivity in the range of 8-14 [micro]m of epoxy-lacquer based coating was tested in an IR-2 double wave IR radiometer (Shanghai Institute of Technological Physics of the Chinese Academy of Sciences).
(1984) developed two separate models (1 and 2) to predict daytime and nighttime sky emissivity. The two models were based on five years' measurements and analysis at Carpentras, France through January 1976 to December 1980.
(17,18) In a recent report, (19) it was shown for a multi-layered Cu-C-Mn-Si-O based nanocrystalline thin films which was produced by sol gel on SS substrate that a maximum absorptance of 0.95 and emissivity of 0.12 at 100[degrees]C can be realized where each layer was between 50 and 100 nm.
Instead, the emissivity of an object is first linked by Stewart's law [5,6] to its reflectivity, before a cavity is ever constructed
Furthermore, the emissivity for all three components is very low compared with the main heat sink emissivity, therefore the emissivity of the main heat sink plays a decisive role in heat transfer.
A solar cavity receiver with the similar geometry to CESA1 receiver 22] was adopted in the present work for studying the influence of surface emissivity. The cavity is a prism with inclined top and bottom faces, which is shown in Figure 1.
Moreover the measurement results can be affected by undesired standing waves, leading to an overestimation of emissivity of the sample.
The thermal shield consists of stainless steel panels with a low emissivity surface (<0.05) that are actively cooled by helium gas, which flows inside the cooling tube welded on the panel surface.