urinary 1-hydroxypyrene is frequently used as a major metabolite and biological indicator of the overall exposure to polycyclic aromatic hydrocarbons. in this study, solid phase extraction was appropriately conditioned with regard to sample ph, sample concentration, loading flow rate, elution solvent, washing solvent, sample volume and sorbent mass. octadecyl silica cartridge (c18) was used as ...

Natural formation of the bcc modification for Co was demonstrated to occur upon precipitation of Co in supersaturated Au90Co10 alloy. The microstructural evolution was investigated by high resolution transmission electron microscopy. Co precipitation starts with the formation of very thin coherent plates along {100}Au. This initially precipitated Co was shown to be a hitherto unknown metastable...

this study is concerned with the prediction of particles’ velocity in a dilute turbulent gas-solidboundary layer flow using a fully eulerian two-fluid model. the closures required for equationsdescribing the particulate phase are derived from the kinetic theory of granular flows. gas phaseturbulence is modeled by one-equation model and solid phase turbulence by mlh theory. resultsof one-way and...

A N-benzyl-4-amino-2,2-dimethylbutanoic acid-based system has been developed as a new oxidatively activated safety catch linker for reaction monitoring and optimisation on solid support. The CAN promoted oxidative debenzylation of the tertiary N-benzylamine moiety, followed by concomitant cyclisation and release of alcohols and amines has been demonstrated both in solution phase model studies a...

 phenytoine derivatives were synthesized , via the  pinacol condensation  with the  reaction of 1,3- diphenyl- propane- 1,3- dione (benzyl) analogs with urea or thiourea in presence of slica gel and solid KOH as Solid phase catalyst  in the mortar / pestle at room temperatures. The reaction was completed at short reaction times (approximately 15min) and pure products were obtained with high yie...

phenytoine derivatives were synthesized , via the pinacol condensation with thereaction of 1,3- diphenyl- propane- 1,3- dione (benzyl) analogs with urea or thioureain presence of slica gel and solid KOH as Solid phase catalyst in the mortar / pestle atroom temperatures. The reaction was completed at short reaction times (approximately15min) and pure products were obtained with high yields (81-9...