Finding the Way to Solar Fuels with Dye-Sensitized Photoelectrosynthesis Cells.

The dye-sensitized photoelectrosynthesis cell (DSPEC) integrates high bandgap, nanoparticle oxide semiconductors with the light-absorbing and catalytic properties of designed chromophore-catalyst assemblies. The goals are photoelectrochemical water splitting into hydrogen and oxygen and reduction of CO by water to give oxygen and carbon-based fuels. Solar-driven water oxidation occurs at a photoanode and water or CO reduction at a cathode or photocathode initiated by molecular-level light absorption.

Polyethylenimine-enhanced electrocatalytic reduction of CO₂ to formate at nitrogen-doped carbon nanomaterials.

Nitrogen-doped carbon nanotubes are selective and robust electrocatalysts for CO2 reduction to formate in aqueous media without the use of a metal catalyst. Polyethylenimine (PEI) functions as a co-catalyst by significantly reducing catalytic overpotential and increasing current density and efficiency. The co-catalysis appears to help in stabilizing the singly reduced intermediate CO2(•-) and concentrating CO2 in the PEI overlayer.

Pump-probe microscopy: spatially resolved carrier dynamics in ZnO rods and the influence of optical cavity resonator modes.

Femtosecond pump-probe microscopy is used to investigate the charge recombination dynamics at different points within a single needle-shaped ZnO rod. Recombination in the tips of the rod occurs through an excitonic or electron-hole plasma state, taking place on a picosecond time scale. Photoexcitation in the larger diameter sections of the interior exhibit dramatically slower recombination that occurs primarily through defects sites, i.

Trans-10, cis-12-conjugated linoleic acid alters hepatic gene expression in a polygenic obese line of mice displaying hepatic lipidosis.

The trans-10, cis-12 isomer of conjugated linoleic acid (CLA) causes a rapid reduction of body and adipose mass in mice. In addition to changes in adipose tissue, numerous studies have reported alterations in hepatic lipid metabolism. Livers of CLA-fed mice gain mass, partly due to lipid accumulation; however, the precise molecular mechanisms are unknown.

Direct imaging of optical cavity modes in ZnO rods using second harmonic generation microscopy.

Images of second harmonic generation (SHG) in needle-shaped ZnO rods obtained from individual structures show areas of enhanced second harmonic intensity along the longitudinal axis of the rod that are periodically distributed and symmetrically situated relative to the rod midpoint. The spatial modulation is a direct consequence of the fundamental optical field coupling into standing wave resonator modes of the ZnO structure, leading to an enhanced backscattered second harmonic condition that cannot be achieved in bulk ZnO. A more complicated second harmonic image is observed when excitation is below the band gap, which is attributed to whispering gallery modes.

Functional genomic characterization of delipidation elicited by trans-10, cis-12-conjugated linoleic acid (t10c12-CLA) in a polygenic obese line of mice.

Gene expression was measured during t10c12-CLA-induced body fat reduction in a polygenic obese line of mice. Adult mice (n = 185) were allotted to a 2 x 2 factorial experiment consisting of either nonobese (ICR-control) or obese (M16-selected) mice fed a 7% fat, purified diet containing either 1% linoleic acid (LA) or 1% t10c12-CLA. Body weight (BW) by day 14 was 12% lower in CLA- compared with LA-fed mice (P < 0.