Phase angle dependence of sand density observable in hyperspectral reflectance

摘要: Abstract This paper describes measurements of the phase angle dependence sand density observable in hyperspectral reflectance. Bi-directional reflectance distribution principal scattering plane were recorded for samples prepared near minimum and maximum relative densities. Radiative transfer theory granular media a single constituent would predict increased with density. However, sands are usually composite materials, we observed that can actually decrease increasing when dominant constituents semi-translucent, darker fraction typically smaller grains is also present. We postulate under these circumstances, as increases, multiple modes being suppressed absorbing occupies more optimally available pore space.