Fig. 2From: Infrared, Raman and Magnetic Resonance Spectroscopic Study of SiO2:C NanopowdersThe Raman spectra of the initial SiO2:C sample measured with different laser wavelengths (a) and the comparison of Raman spectra measured in the initial and annealed SiO2:C samples with 633 nm excitation (b)Back to article page