Ram 2 ft raman module

For NIR FT-Raman spectroscopy analysis, a small piece of bread (~5 g) was removed from the center of the slice. Measurements were performed using back-scattering geometry with a Bruker RAM II FT-Raman module coupled to a Bruker Vertex 70v interferometer, as previously reported by [36 (link)]. The laser excitation wavelength was 1064 nm, and each spectrum was acquired by averaging 128 interferograms at a resolution of 4 cm⁻¹ in the range of 250–3500 cm⁻¹ with a Blackmann-Harris 3-Term apodization function to more precisely determine the peak position of the pyranose ring breathing band that peaked at ~480 cm⁻¹; this single band was selected by considering the spectral range of 460–510 cm⁻¹. As residual fluorescence was present, following baseline correction, the band intensity was normalized in this selected range. Finally, post-zero filling was applied to the 460–510 cm⁻¹ spectral range, with a zero-filling factor of 64, providing a very accurate band profile. With this spectral pre-processing and using the peak-picking function of the Bruker OPUS 6.5 software, the peak position was obtained with an accuracy of 0.01 cm⁻¹, as certified by Bruker Corporation (Billerica, MA, USA).

The FTIR spectra of the polymers were obtained using a Bruker Equinox 55 Fourier transform infrared spectrometer (Bruker, Billerica, MA, USA) (frequency range 4,000 to 500 cm^-1). The UV-vis spectra of the samples were recorded on a UV-vis spectrophotometer (UV4802, Unico, Dayton, NJ, USA). Raman spectra were recorded in a backscattering geometry with a 1,064-nm excitation wavelength using a Bruker Vertex 70 FT infrared spectrometer (equipped with RamIIFT Raman Module). XRD patterns have been obtained using a Bruker AXS D8 diffractometer with a monochromatic Cu-Kα radiation source (λ = 0.15418 nm); the scan range (2θ) was 10° to 80°. Morphology and microstructure of the samples were investigated by FESEM (Hitachi S-4800, Hitachi Ltd., Chiyoda-ku, Japan). TEM measurements were performed on a TEM instrument (JEOL model 2100, JEOL Ltd., Tokyo, Japan).