The application of near infrared spectroscopy in nutritional intervention studies

Functional near infrared spectroscopy (NIRS) is a non-invasive optical imaging technique used to monitor cerebral blood flow (CBF) and by proxy neuronal activation. The use of NIRS in nutritional intervention studies is a relatively novel application of this technique, with only a small, but growing, number of trials published to date. These trials—in which the effects on CBF following administration of dietary components such as caffeine, polyphenols and omega-3 polyunsaturated fatty acids are assessed—have successfully demonstrated NIRS as a sensitive measure of change in hemodynamic response during cognitive tasks in both acute and chronic treatment intervention paradigms. The existent research in this area has been limited by the constraints of the technique itself however advancements in the measurement technology, paired with studies endeavoring increased sophistication in number and locations of channels over the head should render the use of NIRS in nutritional interventions particularly valuable in advancing our understanding of the effects of nutrients and dietary components on the brain

Ethanol steam reforming over Pt/Al2O3 and Rh/Al2O3 catalysts: the effect of impurities on selectivity and catalyst deactivation

Bioethanol contains different types of organic impurities which can have a significant influence on the catalytic performance during steam reforming of bioethanol. Different C3 functional group impurities were added individually to the pure ethanol to investigate the influence of different functional groups on the ethanol steam reforming reaction over 0.2% Pt/Al2O3 and 0.2% Rh/Al2O3 catalysts at 773 K. It was established that the catalytic behaviour of both of the catalysts is significantly influenced by the different impurities. The addition of 1 mol% C3 alcohols (1-propanol and isopropyl alcohol) decreased the conversion of ethanol and increased the rate of catalyst deactivation. This deactivation of the catalyst in the presence of C3 alcohols was attributed to high olefin formation and incomplete decomposition of the C3 alcohols, which deposited over the catalysts as coke. Propanal, propylamine and acetone addition to the water/ethanol mixture resulted in rapid metal deactivation and a loss of steam reforming activity over the Pt/alumina although ethanol decomposition continued. In contrast the Rh/alumina did not lose all steam reforming activity when acetone and propylamine were added as impurities. On both the catalysts alcoholic impurities produced a large number of carbon nanotubes (CNTs)