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A potentiometric system is described for the indirect flow determination of A3+ with an aluminum wire as indicator electrode. The method is based on the reaction between aluminum and fluoride ions at pH 5.0 in acetate buffer. The reduction in activity of fluoride ions is detected by the aluminum electrode. The response was optimized for the flow rate of solution, length of reaction tubing, concentration of fluoride reagent, and pH of the buffer. The response was linear with concentration of aluminum in the range of 0.5 to 50 ppm with a relative standard deviation (RSD) of 0.7%. There was negligible interference from a range of cations and anions when their concentrations were less than 20 PPm,

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New flat sheet membranes possessing both organic antifouling and antibacterial properties were fabricated. The successive modification of PES with HPEI and nAg resulted in enhanced membrane properties. Most of the membranes exhibited good antibacterial activities against the bacterial strains tested. Membrane samples with nAg also displayed good antibacterial activities against bacteria E Coli. The use of cost friendly HPEI and low levels of modification, and ease of membrane fabrication was achieved.

Ferrocenylimidazolium salts with methylene and phenyl groups bridging the ferrocenyl and alkylimidazolium moieties were synthesized and characterized by spectroscopic and analytical methods. Crystal structures of two new compounds are also reported. Cyclic voltammetry was used to analyze the influence of the two bridging groups or spacers on electrochemical properties of the salts relative to the shifts in the formal electrode or peak potentials (E 0 or E 1/2 ) of the ferrocene/ferrocenium redox couple. Results from this study showed that all the salts exhibited higher electrode potentials relative to ferrocene, which is due to the electron-withdrawing effect of the imidazolium ion on the ferrocenyl moiety. Application of the salts as catalysts in transfer hydrogenation of ketones resulted in high conversion of saturated ketones to corresponding alcohols and turnover numbers as high as 1880. The catalysts were chemoselective towards reduction of the C ═ C bonds of conjugated 3-penten-2-one and 4-hexen-3-one to yield saturated ketones, while unconjugated 5-hexen-2-one was hydrogenated to an unsaturated alcohol.