The aim of this study is the rapid detection of food pressed oils adulteration with their refined versions, using UV–Vis spectroscopy. The study investigates some common oil physico-chemical parameters such are: density, viscosity, refractive index, acid index, peroxide value, saponification index, to detect differences between cold pressed oils versus refined ones, for some food-grade oils found on Romanian market, as well as FT-IR spectroscopy and GC–MS analytical method, obtaining similar results to those presented in the literature data. The difference between some of the obtained results is not relevant for telling the cold-pressed oils from their refined version for adulteration investigation purpose. Colour analysis instead is a very good method to differentiate a cold pressed oil from a refined one. Taking this into account, the cold pressed oils and their refined versions were mixed in different proportions, and their colour properties were analyzed, obtaining linear dependences for a* and b* CIE L*a*b* parameters with cold pressed oil content in the mixture. Dependence equations were proposed.

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This paper presents the synthesis of eight new pyrazole azo dyes using ethyl 5-amino-3-methyl-1H-pyrazole-4-carboxylate as the diazotization component and various active methylene derivatives as coupling components. These new azo dyes were characterized by spectroscopic (FT-IR, UV-VIS), and spectrometric (1H NMR, 13C NMR, MS) analyses. The dye structures were modeled by the MMFF94s force field and quantum chemical density functional theory (DFT) calculations using the B3LYP functional and the 6-311G(d,p) basis set, in the gas phase. Weak electrostatic hydrogen bonds for the azo and hydrazo dye tautomers were found in the ground state. The CIS, TD (using the B3LYP and M06-2X functionals), and ZINDO methods were used to estimate the dye UV-VIS spectra in ethanol, which were compared with the experimental ones. The anti-configuration arrangement of the π-bonds and the presence of the prevalent hydrazo dye tautomer were supported by the computed 1H NMR and 13C NMR spectra. A good accordance between the experimental and predicted absorption maxima and chemical shifts was observed. Color investigations using the CIEL*a*b* space were conducted for all dyes in powder and for their mixtures in water-based acrylic resins. The results confirm the newly synthesized dyes’ color properties and that they might be used for light color paints in the varnishes industry.

An original method for the preparation of N,N '-bis(endo-5-norbornen-2,3-dicarboxy-imidyl) carbonate from endo-N-hydroxy-5-norbornen-2,3-dicarboximide in basic catalyst has been investigated. FT-IR studies performed in order to monitor the reaction allowed the identifying of the laboratory optimal conditions (reaction time, molar ratio). The method requires limited quantities of organic solvents and reagents, leading to an economical and environmental friendly process for the preparation of a new symmetrical organic carbonate.

The synthesis of mixed primary-, secondary-, and tertiary-alkyl phthalimidyl carbonates from N,N�-Diphtalimidylcarbonate (DPC) can be performed in a facile way, in one step reaction and with good yields. This new carbonate compound is usefull for peptide synthesis in preparation of active esters (activation step) and also in the protecting reactions by alkoxycarbonylation at nitrogen nucleophiles of amine- and aminoacid-types. It was proved that N,N�-diphtalimidylcarbonate (DPC) exhibited a similar reactivity to N,N�-disuccinimidylcarbonate, but the advantage of DPC seems to be that N-hydroxyphthalimide can be easily recovered quantitatively after the reaction.