Abstract: A method for extraction and analysis of polycyclic aromatic hydrocarbons (PAHs) uses a solvent mixture that is effective for extraction and also compatible with disposable polypropylene solid phase extraction (SPE) tubes. The petroleum product is mixed with an organic solvent, then an extraction solvent made up of a volume ratio of 70:30 to 90:10 acetonitrile to ethyl acetate is added to the mixture. The organic solvent and PAHs are adsorbed in the extraction solvent mixture, leaving the oils behind. The extract, including the solvents and PAHs, can be transferred to a disposable SPE tube for further sample processing, analysis and disposal.

Abstract: A strategy for enzymatic biomass conversion that involves enzyme recovery and reuse. Enzyme recovery is achieved by attaching enzymes to paramagnetic nanoparticles. By magnetically attracting the paramagnetic nanoparticles, enzymes may be recovered for reuse. The process of enzymatic biomass hydrolysis includes: attaching biomass degrading enzymes to a surface of functionalized particles having paramagnetic properties; mixing the particles with a biomass; recovering the enzymes via magnetic separation; and re-using the enzymes in a subsequent process. The process provides a product feed stream which may be subjected to further processing. The process may be repeated multiple times wherein the biomass is sequentially subjected to different enzymes.

Abstract: A multimedia distribution device includes a nonvolatile memory that stores a compressed media signal in which at least two scenes are selectively compressed using different codecs from a codec library, the codecs being automatically selected to produce a highest compression quality for the respective scenes according to a set of criteria without exceeding a target data rate. The nonvolatile memory also stores a plurality of codec indicators specifying which codecs from the codec library were used to respectively compress each scene within the compressed media signal.