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Thin films of indium molybdenum oxide (IMO) were rf sputtered onto glass substrates at room temperature. The films were studied as a function of sputtering power (ranging 40-180 W) and sputtering time (ranging 2.5-20 min). Thickness of the films found varied between 50-400 nm. The films were characterized for their structural (XRD), electrical (Hall measurements) and optical (Transmittance spectra) properties. XRD studies revealed that the films are amorphous for the sputtering power ≤ 100 W and deposition time ≤ 5 min. All the other films are polycrystalline and the strongest refection along (222) plane showing a preferential orientation. A minimum bulk resistivity of 2.65 × 10-3 Ω-cm and a maximum carrier concentration of 4.16 × 1020 cm-3 have been obtained for the films sputtered at 180 W (10 min). Whereas maximum mobility (19.5 cm2 V-1 s-1) has been obtained for the films sputtered at 80 W (10 min). A maximum visible transmittance of 90% (500 nm) has been obtained for the films sputtered at 80 W (10 min) with a minimum of 27% for those sputtered at 180 W. The optical band gap of the films found varying between 3.75 and 3.90 eV for various sputtering parameters. © 2006 Materials Research Society.

Thin films of molybdenum doped indium oxide (IMO) were rf sputtered onto glass substrates at room temperature. The films were studied as a function of oxygen volume percentage (OVP) ranging 1.4 - 10.0% in the sputtering chamber. The thickness of the films found varying between 180 and 260 nm. The X-ray diffraction pattern showed the films are polycrystalline with the peaks corresponding to (222) and (400) planes and one among them showing as a preferential orientation. It is observed that the preferred orientation changes from (222) plane to (400) as the OVP increases from 1.4 to 10.0%. The transmittance spectra were found to be in the range of 77 to 89%. The optical band gap calculated from the absorption coefficient of transmittance spectra was around 3.9 eV. The negative sign of Hall coefficient confirmed the films were n-type conducting. The bulk resistivity increased from 2.26×10 -3 to 4.08×-1 Ωcm for the increase in OVP from 1.4 to 4.1%, and thereafter increased dramatically so as the Hall coefficients were not detectable. From the AFM morphologies it is evaluated that the RMS roughness of the films ranges from 0.9 to 3.2 nm. © 2006 Materials Research Society.

A multi-product model for the design of global supply chains with reverse flows is proposed. Two levels of decisions are considered, one strategic and one tactical. The first is modelled through a macro perspective of time where the determination of the network structure and flows is accomplished. At tactical level, a micro perspective of time is considered, where production planning and inventory management are addressed in detail. A mixed integer linear programming formulation is developed which is solved with standard Branch and Bound techniques. The model accuracy and suitability are studied using a case study.

Molybdenum doped indium oxide (IMO) thin films rf sputtered at room temperature were studied as a function of oxygen volume percentage (O 2 vol. %) varied between 0 and 17.5. The as-deposited films were amorphous irrespective of O2 vol. %. The minimum transmittance (<10 %) of the films deposited without oxygen has been increased on introducing oxygen (3.5 O2 vol. %) to a maximum of 90 %. The optical band gap has been increased from 3.80 eV (without oxygen) to 3.92 eV (3.5 O 2 vol. %). The films were highly resistive and the hall coefficients were detectable only for the films deposited without oxygen. In order to increase the electrical conductivity, the films were annealed in the range 100-500° C in open-air and N2/H: gas for 1 hour. The annealed films become polycrystalline with enhanced electrical and optical properties. The effect of annealing conditions on these films will be presented and discussed in detail. © 2006 Materials Research Society.

Pseudoazurin binds at a single site on cytochrome c peroxidase from Paracoccus pantotrophus with a K-d of 16.4 muM at 25 degreesC, pH 6.0, in an endothermic reaction that is driven by a large entropy change. Sedimentation velocity experiments confirmed the presence of a single site, although results at higher pseudoazurin concentrations are complicated by the dimerization of the protein. Microcalorimetry, ultracentrifugation, and H-1 NMR spectroscopy studies in which cytochrome c550, pseudoazurin, and cytochrome c peroxidase were all present could be modeled using a competitive binding algorithm. Molecular docking simulation of the binding of pseudoazurin to the peroxidase in combination with the chemical shift perturbation pattern for pseudoazurin in the presence of the peroxidase revealed a group of solutions that were situated close to the electron-transferring heme with Cu-Fe distances of about 14 Angstrom. This is consistent with the results of H-1 NMR spectroscopy, which showed that pseudoazurin binds closely enough to the electron - transferring heme of the peroxidase to perturb its set of heme methyl resonances. We conclude that cytochrome c550 and pseudoazurin bind at the same site on the cytochrome c peroxidase and that the pair of electrons required to restore the enzyme to its active state after turnover are delivered one-by-one to the electron-transferring heme.

The present work reports results obtained from a series of preliminary experiments
aiming at complementing the current knowledge about the wear behaviour of centrifugally-cast
FGM Al/SiCp composites, through concurrent corrosion processes. Precursor MMC’s were
prepared by rheocasting, using 118.8 μm SiC particles and an Al-10Si–2.2 Mg alloy. Those MMC’s
were then molten and centrifugally cast in order to produce cylindrical FGMMC’s. Discs machined
from the top surface of each sample were tested against nodular cast iron pins, using an inverted
configuration pin-on-disc tribometer. Sliding tests took place at room temperature, over a 50000 m
sliding distance, with a sliding speed of 0.3 m s-1, under a 5 N normal load; both dry-sliding and
water-lubricated tests were performed. In order to elucidate the mechanisms involved, the wear
coefficients were calculated for each condition, and the samples were subjected to morphological
characterization via SEM/EDS. Concurrently, in the case of the water-lubrication tests, the
corrosion potential of the tribological pair was monitored. The results obtained show an increase in
material loss for the water-lubricated cases, although variations are registered depending on
reinforcing particle volume fraction. At the same time, the open circuit potential response of the
tribological pair may be correlated with the events of formation/destruction of the tribolayers.