Synthesis and application of 4-dipropylaminodiazabenzene-4′-isothiocyanate to the derivatization and chromatographic separation of biogenic amines

Summary The physicochemical properties of biogenic monoamines, their polar character, lability and trace amounts found in the biological material create great analytical difficulties in their identification and separation. The selective chromatographic separation of those amines is greatly facilitated by their derivatization [1]. Based on theoretical considerations, 4-dipropylaminodiazabenzene-4′-isothiocyanate (DPABITC) was synthetized and applied to the preparation of thiocarbamoyl derivatives of the amines. The coloured derivatives were separated by TLC. Presented at Balaton Symposium on High Performance Separation Methods, Siófok, Hungary, September 1–3, 1999     

Study of α- and β-relaxation processes in supercooled sucrose liquids

The relaxation map of highly concentrated sucrose water mixtures was built using mechanical and impedance spectroscopies. Data of - and -relaxation processes obtained with both techniques complete calorimetric and rheological measurements. The temperature evolutions of the relaxations were extrapolated using the measured data and the equations commonly used to describe the relaxations: Arrhenius and WLF behaviours for respectively the - and -relaxations. The temperature/frequency domain when and processes merge for 99% sucrose solution is discussed with respect to scenery proposed in the literature.This revised version was published online in November 2005 with corrections to the Cover Date.