Comprehensive evaluation of imidazole-based polymers for the enrichment of selected non-steroidal anti-inflammatory drugs.

This study reports the comparison of four manufactured imidazole-based copolymers and two commercially available hydrophilic sorbents for the solid phase extraction (SPE) of selected non-steroidal anti-inflammatory drugs (NSAID). Different hydrophilic copolymers were obtained by a suspension polymerization using a styrene-based and a methacrylate-based cross-linker and by single step modifications for enhancing the ion-exchange character. SPE protocols were optimized for both non-modified and modified sorbents and applied for the enrichment of selected NSAID using all six copolymers.

Exsolution of Fe and SrO Nanorods and Nanoparticles from Lanthanum Strontium Ferrite LaSrFeO Materials by Hydrogen Reduction.

Formation of uniform Fe and SrO rods as well as nanoparticles following controlled reduction of LaSrFeO (LSF) and Ni-LSF samples in dry and moist hydrogen is studied by aberration-corrected electron microscopy. Metallic Fe and SrO precipitate from the perovskite lattice as rods of several tenths of nm and thicknesses up to 20 nm. Based on a model of Fe whisker growth following reduction of pure iron oxides, Fe rod exsolution from LSF proceeds via rate-limiting lattice oxygen removal.

Water-Gas Shift and Methane Reactivity on Reducible Perovskite-Type Oxides.

Comparative (electro)catalytic, structural, and spectroscopic studies in hydrogen electro-oxidation, the (inverse) water-gas shift reaction, and methane conversion on two representative mixed ionic-electronic conducting perovskite-type materials LaSrFeO (LSF) and SrTiFeO (STF) were performed with the aim of eventually correlating (electro)catalytic activity and associated structural changes and to highlight intrinsic reactivity characteristics as a function of the reduction state. Starting from a strongly prereduced (vacancy-rich) initial state, only (inverse) water-gas shift activity has been observed on both materials beyond ca. 450 °C but no catalytic methane reforming or methane decomposition reactivity up to 600 °C.

Separation of small molecules on novel monolithic poly(vinylphosphonic acid/ethylene dimethacrylate) columns.

In HPLC, monolithic organic stationary phases are usually restricted to the separation of high-molecular-weight compounds such as proteins or oligonucleotides. The aim of this study was to enlarge the applicability of monolithic stationary phases to the micro-liquid chromatography separation of smaller molecules. For this, a new monolithic stationary phase was synthesized by radical polymerization of vinylphosphonic acid (VPA) and ethylene dimethacrylate (EDMA) using azobisisobutyronitrile as radical initiator.