Nachweis von 4-Hydroxycumarinderivaten mittels Derivativspektroskopie (Ableitungs-Spektroskopie)

Abstract

Presented here is a rapid method of identifying 4-hydroxycoumarins in organs or blood samples. Using an ultrasonic homogenizer, a complete analysis is obtained in less than 30 min. Coumarin derivatives are identified by means of derivative UV spectroscopy in the normal spectrum and its first derivation at 340 to 240 nm. HPTLC can be employed as supplementary identification method.

Kinetic study of methylamine reforming over a silica-alumina catalyst

“…The rates of MMA reforming were determined to be proportional to the partial pressure of MMA while DMA reforming is controlled by a surface reaction so that the rate is proportional to the square root of the DMA partial pressure. Weigert (1981Weigert ( , 1987 obtained relative rates of the reforming reactions over sodium mordenite, Davison D-970 silica-alumina, and Harshaw AL-0104 alumina through his analysis of the kinetics of the methanol amination reaction. His results, displayed in Table 1, show that the nature of the catalyst has a significant effect on the relative rates of the reforming reactions.…”