Tag: M.W=50-100

Ribeiro, J. S. published the artcilePrediction of sensory properties of Brazilian Arabica roasted coffees by headspace solid phase microextraction-gas chromatography and partial least squares, SDS of cas: 20662-83-3, the publication is Analytica Chimica Acta (2009), 634(2), 172-179, database is CAplus and MEDLINE.

Volatile compounds in fifty-eight Arabica roasted coffee samples from Brazil were analyzed by SPME-GC-FID and SPME-GC-MS, and the results were compared with those from sensory evaluation. The main purpose was to investigate the relationships between the volatile compounds from roasted coffees and certain sensory attributes, including body, flavor, cleanliness and overall quality. Calibration models for each sensory attribute based on chromatog. profiles were developed by using partial least squares (PLS) regression. Discrimination of samples with different overall qualities was done by using partial least squares-discriminant anal. (PLS-DA). The alignment of chromatograms was performed by the correlation optimized warping (COW) algorithm. Selection of peaks for each regression model was performed by applying the ordered predictors selection (OPS) algorithm in order to take into account only significant compounds The results provided by the calibration models are promising and demonstrate the feasibility of using this methodol. in online or routine applications to predict the sensory quality of unknown Brazilian Arabica coffee samples. According to the PLS-DA on chromatog. profiles of different quality samples, compounds 3-methypropanal, 2-methylfuran, furfural, furfuryl formate, 5-methyl-2-furancarboxyaldehyde, 4-ethylguaiacol, 3-methylthiophene, 2-furanmethanol acetate, 2-ethyl-3,6-dimethylpyrazine, 1-(2-furanyl)-2-butanone and three others not identified compounds can be considered as possible markers for the coffee beverage overall quality.

Analytica Chimica Acta published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, SDS of cas: 20662-83-3.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Al-Duri, B. published the artcileSupercritical water oxidation (SCWO) for the removal of N-containing heterocyclic hydrocarbon wastes. Part I: Process enhancement by addition of isopropyl alcohol, Category: oxazolidine, the publication is Journal of Supercritical Fluids (2016), 155-163, database is CAplus.

The present work investigates the destruction of nitrogen-containing heterocyclic hydrocarbons frequently encountered in hazardous wastes by supercritical water oxidation (SCWO), with focus on the process enhancement using iso-Pr alc. (IPA) as co-fuel. 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) was selected for SCWO in a continuous plug flow reactor, under a range of temperatures (400-525°C), oxidant ratios nSR (0.8-2.0) and IPA/DBU ratios (0.5-3.5). Exptl. results were presented in terms of total organic carbon (TOC) removal %, and nitrogenous products yield %. Based on GC-MS anal., a free radical reaction mechanism for SCWO of DBU was proposed. Results showed that temperature was the predominant factor to influence the rate of DBU oxidation, while oxidant ratio (nSR) significantly affected the N speciation in the exit stream. IPA addition had a significant impact on shifting recalcitrant aqueous ammonia NH⁺₄ in the liquid stream to gaseous nitrogen. It also increased TOC removal% (DBU + IPA) due to the increased free radicals produced by IPA oxidation

Journal of Supercritical Fluids published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Category: oxazolidine.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem

Bogdanov, V. S. published the artcileCarbon-13, nitrogen-14, and proton NMR spectra and effects of substituents in oxazoles, Application In Synthesis of 20662-83-3, the publication is Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya (1980), 305-16, database is CAplus.

¹³C NMR data were obtained for 40 oxazoles; ¹H and ¹⁴N data were obtained for 6 and 11 of these, resp. The following linear correlations were made: chem. shift (δ) for C-2 with δ for C-4, δ for C-4 with δ for C-5, δ for C-2 with δ for H-2, δ for C-4 with δ for H-4, δ for C-5 with the electronegativity of the substituent at C-5, and ¹³C δ values for 4,5-disubstituted oxazole with those for 1,2-disubstituted benzenes. An additive method for calculating ¹³C δ values was tested successfully. The effect of substituents on various coupling constants was also determined

Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya published new progress about 20662-83-3. 20662-83-3 belongs to oxazolidine, auxiliary class Oxazole, name is 4,5-Dimethyloxazole, and the molecular formula is C5H7NO, Application In Synthesis of 20662-83-3.

Referemce:
https://en.wikipedia.org/wiki/Oxazolidine,
Oxazolidine | C3H7NO – PubChem