J. Inst. Brew. 111(1), 20–25, 2005 Proanthocyanidins have been characterized and levels compared in an ale and a lager using normal-phase liquid chromatography– mass spectroscopy (LC/MS) after a pre-concentration step employing Sephadex LH-20 chromatography. Twenty proanthocyanidins were identified including both non-galloylated and galloylated forms of the monomers, dimers and trimers. Oligome...

Small-angle neutron scattering contrast variation is applied to characterization of nanoporous low-dielectric constant (low-k) thin films. Films are exposed to saturated solvent vapor in air, whereby the pores fill with liquid by capillary condensation. The pores are filled with mixtures of hydrogen- and deuterium-containing solvents to vary the neutron contrast with the matrix (wall). The comp...

Eu-doped BaTiO3 thin films with a pseudo-cubic perovskite structure were successfully fabricated on magnesia substrates at low temperature by using a high-concentration sol–gel process, in which the newly developed gel-aging process on substrate was employed. Film microstructure, crystallinity, sintering properties and photoluminescence (PL) were investigated. The xerogel thin films exhibited s...

Durability and limited catalytic activity are key impediments to the commercialization of polymer electrolyte fuel cells. Carbon materials employed as catalyst support can be doped with different heteroatoms, like nitrogen, to improve both catalytic activity and durability. Carbon xerogels are nanoporous carbons that can be easily synthesized in order to obtain N-doped materials. In the present...

This study focuses on the development of an optical ammonia gas sensor, the sensing mechanism of which is based on Förster resonance energy transfer (FRET) between coumarin and fluorescein. The dyes were immobilized into an organically modified silicate matrix during polymerizing methyltriethoxysilane with trifluoropropyltrimethoxysilane on a poly(methyl methacrylate) substrate. The resulting d...

We demonstrate the nonaqueous self-assembly of a low-molecular-mass organic gelator based on an electroactive p-type tetrathiafulvalene (TTF)-dipeptide bioconjugate. We show that a TTF moiety appended with diphenylalanine amide derivative (TTF-FF-NH2) self-assembles into one-dimensional nanofibers that further lead to the formation of self-supporting organogels in chloroform and ethyl acetate. ...

A planar ultramicroelectrode nitric oxide (NO) sensor was fabricated to measure the local NO surface concentrations from NO-releasing microarrays of varying geometries. The sensor consisted of platinized Pt (25 microm) working electrode and a silver paint reference electrode coated with a thin silicone rubber gas permeable membrane. An internal hydrogel layer separated the Pt working electrode ...