Nanometer-sized aluminum powder was synthesized by thermal decomposition of an alane solution in the presence of a titanium catalyst under an inert atmosphere. The resulting material, formally devoid of an oxide layer, was used to reduce complexes of gold, nickel, palladium, and silver. The reduction process yielded materials that contained the transition metal at a level between 1 and 3 atom % on a metals basis, as determined by inductively coupled plasma atomic emission spectroscopy and energy dispersive spectroscopy. After exposure to air at ambient conditions, the transition metal treated aluminum materials were found to contain less aluminum oxide than an aluminum sample that was not treated with a transition metal. The nickel treated sample contained as much or more metallic aluminum as the untreated aluminum sample, indicating that the passivating layer in the nickel treated aluminum was highly efficient at protecting the underlying aluminum.

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Canopy scale fluxes of isoprene and monoterpenes were investigated in both wet and dry seasons above a rubber tree (Hevea brasiliensis)/secondary tropical forest in the Yunnan province of southwestern China. Drought conditions were unusually high during the dry season experiment. The eddy covariance measurement technique was used to measure isoprene fluxes, while monoterpene fluxes were modeled based on leaf level emission measurements. Maximum observed isoprene fluxes occurred during the wet season and daytime average fluxes were about 1 mg C m À2 h À1. Dry season fluxes were much lower with a daytime average of 0.15 mg C m À2 h À1. Wet season isoprene fluxes compare quite well with isoprene fluxes observed from other tropical forests. Monoterpene fluxes came, almost entirely, from Hevea brasiliensis, which is a light-dependent monoterpene emitter. Modeled wet season total monoterpene fluxes were about 2 mg C m À2 h À1 (average for the daytime), and in the dry season were undetectable. Extreme drought conditions, and the drought deciduous nature of Hevea brasiliensis may be the cause of the low dry season fluxes. r

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