Multivariate near infrared spectroscopy models for predicting the methyl esters content in biodiesel

Multivariate near infrared spectroscopy for predicting polyhydroxybutyrate biosynthesis by mixed microbial consortia cultured on crude glycerol

“…This made the model calibration weak with a lower PHB content. However, better calibration model can be expected if a broader spectral range can reach, such as the C]O stretching second overtone at 1950 nm, C]O stretching þ CH 3 stretching combination at 2120 nm [17,24,15,28].…”

Multivariate near infrared spectroscopy models to monitor polycondensation production process reactions

“…It allows multi-component analysis in a fast and non-destructive way, without requiring complex pre-treatments. In the NIR region, a component typically absorbs at more than one wavelength and the absorbance at a given wavelength may have contributions from more than one analyte [3]. Moreover, NIRS affords the simultaneous prediction of physical and chemical parameters from a single spectrum.…”

“…multivariate regression techniques, to develop effective calibration models. In this work, Principal Components Analysis (PCA) was used to perform the qualitative analysis of the data, whereas a Partial Least Squares (PLS) was applied to derive the model that relates the NIR spectra with the acid value and the Average Molecular Weight (AMW), during polycondensation [3]. The correlation between the absorption of NIR radiation and the analytical values, obtained using the reference methods, can be improved through the use of specific spectra pre-processing and variable selection methods.…”

A feasibility study of oil content and fatty acid composition of seed powder and seed oil of Pongamia pinnata by near infrared spectroscopy

“…KNN and SVMs methods were found to be highly effective for biodiesel classification by feedstock oil type. Baptista et al 13 , reported the use of NIR spectroscopy to determine the ester content in biodiesel, which is one of its main properties. In fact, the ester content is an indicator of the degree of conversion of the transesterification reaction.…”