In summary, the epoxy foam with 2 wt% microsphere content, blown at 85[degrees]C, exhibits specific properties, such as high sound absorption coefficient
, great sound TL, and excellent thermal insulation property, while maintaining acceptable mechanical properties.
Such as, the capillary absorption coefficient
of RAC-0% with the load of 0%[f.sub.c], 40%[f.sub.c], 60%[f.sub.c], and 80%[f.sub.c] is, respectively, 973.5 g/([m.sup.2][h.sup.1/2]), 1073.6 g/([m.sup.2][h.sup.1/2]), 1265.0 g/ ([m.sup.2][h.sup.1/2]), and 1649.1 g/([m.sup.2][h.sup.1/2]), and the results are 1245.2 g/([m.sup.2][h.sup.1/2]), 1326.4 g/([m.sup.2][h.sup.1/2]), 1788.4 g/([m.sup.2][h.sup.1/2]), and 2513.8 g/([m.sup.2][h.sup.1/2]) for RAC-100%.
The random distribution of the fibers in the fibrous absorbent materials allows the sound waves to hit the lumen of the fiber bundle and strengthen the sound absorption effect; a high absorption coefficient
can be obtained.
Also, the total path loss is not shown to monotonically increase at the THz frequency band due to the fact that the MAA is caused by isotopologues of gases having various absorption coefficients
at various frequencies.
The effects of [D.sub.t] and [D.sub.f] on the sound absorption coefficient
[alpha] are plotted in Figure 19.
The background medium has scattering coefficient of 10 [mm.sup.-1] and absorption coefficient
of 0.01[mm.sup.-1], respectively, and these values keep the same throughout this paper.
Where [[mu].sub.a(x)] is the absorption coefficient
([cm.sup.-1]), [P.sub.d] is the power density.
We can distinguish the normal people and the affected people since normal people have absorption coefficient
less than 2 [cm.sup.-1] and scattering coefficient values less than 5 [cm.sup.-1].
The measured gas type, its absorption coefficient
, and the gas concentration range all impact the amount of incident light on the thermopile detector, as dictated by the previously discussed Beer-Lambert law.
Photon mass attenuation and energy absorption coefficient
from 1keV to 20MeV.
Nam, "The nonlinear absorption coefficient
of a strong electromagnetic wave by confined electrons in quantum wells under the influences of confined phonons," Journal of Electromagnetic Waves and Applications, Vol.