Non-destructive orientation mapping is an important characterization tool in materials science and geoscience for understanding and/or improving material properties based on their grain structure. Confocal Raman microscopy is a powerful non-destructive technique for chemical mapping of organic and inorganic materials. Here we demonstrate orientation mapping by means of Polarized Raman Microscopy (PRM). While the concept that PRM is sensitive to orientation changes is known, to our knowledge, an actual quantitative orientation mapping has never been presented before. Using a concept of ambiguity-free orientation determination analysis, we present fast and quantitative single-acquisition Raman-based orientation mapping by simultaneous registration of multiple Raman scattering spectra obtained at different polarizations. We demonstrate applications of this approach for two- and three-dimensional orientation mapping of a multigrain semiconductor, a pharmaceutical tablet formulation and a polycrystalline sapphire sample. This technique can potentially move traditional X-ray and electron diffraction type experiments into conventional optical laboratories.

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The possibilities of the decomposition by non-negative least squares (NNLS) and Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) methods of determination of spectra and concentrations of species in multicomponent (up to 8) liquid solutions by analyzing FTIR ATR and Raman spectra are discussed. It is shown that the NNLS decomposition of Raman spectra provides better results than the decomposition of the same mixture measured with the FTIR ATR method. This fact is connected with narrower width and smaller overlap of vibrational peaks obtained with the use of Raman spectroscopy comparing to IR spectroscopy for molecular liquids. It is shown that using the known spectra can increase the total number of species, for which a quantitative information can be successfully obtained. The unknown concentration profiles of an = 8-component liquid mixture can be found correctly if the − 1 spectra of pure components are used as spectral constrains during the MCR-ALS analysis.

Blood analysis by spectroscopic techniques can provide important information about biochemistry and life processes in it. Blood indices are highly variable, and plenty of factors influence them. The present work describes the combination of two methods-IR and Raman spectroscopies of blood applied to investigate gerontology issues. We carried out a pilot study of 74 blood samples. The donors were differentiated by age with the Partial Least Squares (PLS) analysis of Raman and IR spectra. Analyzing the principal component spectra obtained during PLS processn the most illustrative bands were found in the intervals 2860-3030 cm

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