Silicon carbide extinction

Figure 12.1 Calculated extinction efficiencies of silicon carbide spheres in air. The wave number denotes the inverse of the wavelength.

Figure 12.2 Calculated extinction efficiencies of a silicon carbide sphere (0.1 /im) in air and in potassium bromide.

Figure 12.7 Calculated extinction cross section per unit volume of a silicon carbide ellipsoid with geometrical factors 0.1, 0.3, and 0.6. Cext - Cabs for sufficiently small absorbing particles.

Figure 12.15 Measured infrared extinction by silicon carbide particles (dashed curve) compared with calculations for spheres and a continuous distribution of ellipsoids (CDE).

Stephens, J. R., 1980. Visible and ultraviolet (800-130 nm) extinction of vapor-condensed silicate, carbon, and silicon carbide smokes and the interstellar extinction curve, Astrophys. J., 23H, 450-461. 

Hoppe P. and Besmehn A. (2002) Evidence for extinct vanadium-49 in presolar silicon carbide grains from supernovae. Astrophys. J. 576, L69-L72. 

Integration of the spectral results of Hendricks and Howell [253] provides mean extinction coefficient data that can be compared with that of Hsu et al. [88]. The Hale and Bohn [252] data are only for the wavelength of 488 nm. Hendricks and Howell [253] found that a modified geometrical optics relation also fit the data for the spectrally integrated extinction coefficient of both zirconia and silicon carbide. They recommend the relation... 

FIGURE 7.30 Extinction coefficient versus pore diameter for alumina, partially stabilized zirconia, and silicon carbide. 

Various potential applications of nanoSIMS in characterization of solids have already been recognized. Though the technique seems to be promising in cosmochemical analysis, its real application is still limited due to the strong isobaric interference. However, nanoSIMS is a more flexible alternative for elements that are ionized easily (Hoppe et al. 2004 Marhas et al. 2003) when compared with RIMS or TIMS. Hoppe et al. (2004) of MPl for Chemistry, Mainz, reported the measurement of extinct A1, Mn, and Fe in meteoritic minerals formed early in solar system history. They also measured extinct Ti and and s-process Ba in pre-solar silicon carbide grains of supernova origin. 

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