Ultrafine Fe, Fe–Ni, and Ni particles were prepared by using the hydrogen plasma-metal reaction method in a mixture of H2 and Ar of 0.1 MPa. The particles were characterized by x-ray diffraction, transmission electron spectroscopy, energy disperse spectroscopy, chemical analysis, and Mössbauer spectroscopy. In contrast with bulk Fe–Ni alloys, the distinguishing features in corresponding ultrafine particles are that two phases with fcc and bcc structures coexist in a wide composition range. Ultrafine Fe–Ni particles have higher resistance to oxidation than Fe and Ni particles. The mechanism of forming particles was analyzed by means of structural and magnetic measurements. It was found that quenching is a dominant mechanism for forming paramagnetic particles. Hyperfine interactions were studied by Mössbauer spectroscopy in comparison with those in bulk Fe–Ni alloys.

Polymer surfaces terminated with a specific chemical functionality are attractive for biomaterial applications because of the predictability and selectivity of surface reactions towards the anchoring of a biochemical agent to the polymer. In the present work, engineering of surface functionality was performed using OH radicals generated in gas phase by the reaction between a hot filament and water molecules in vacuum. The generation of OH was confirmed by laser induced fluorescence spectroscopy. The incorporation of oxygen and formation of alcohol groups on polystyrene were confirmed by x-ray photoelectron spectroscopy. High resolution electron energy loss spectroscopic data also showed that for polystyrene with an uptake of less than a monolayer equivalent of oxygen, C-OH was the only detectable surface functionality containing oxygen.