Tantalum(V) reacts with 5-iodo-8-hydroxyquinoline-7-sulphonic acid to form a yellowish coloured complex having maximum absorbance at 405 nm in citric acid medium. The relatively slow reaction at room temperature is completed in 10 minutes at 40 °c. The colour is stable for at least 12 hr. Effects of heating temperature, time, pH, reagent concentration and other variables have been studied. The ...

Tantalum cobalt nitride photocatalysts were prepared using a simple drop coating method on a Ta foil substrate followed by thermal ammonia treatment, and their photoelectrochemical (PEC) properties for water oxidation under visible light were studied. The resulting Ta0.9Co0.1Nx films showed a photocurrent of ca. 1.5 mA/cm (12 times higher than that of Ta3N5) under 100 mW/cm visible light irradi...

The deposition of x-ray energy resulting from the microexplosion i.o an inertial confinement fusion reactor and the subsequent thermal response of candidate wall coating and structural materials is examined. Evaporation losses and resulting melt layer thicknesses for these materials exposed to a variety of different x-ray energies and spectra are calculated. Softer x-ray energy spectra absorbed...

We present an artificial viscosity scheme tailored to finite-deformation Lagrangian calculations of shocks in materials with or without strength on unstructured tetrahedral meshes of arbitrary order. The artificial viscous stresses are deviatoric and satisfy material-frame indifference exactly. We have assessed the performance of the method on selected tests, including: a two-dimensional shock ...

We report the design, optimization, and experimental results of large area commercial silicon solar cell based thermophotovoltaic (TPV) energy conversion systems. Using global non-linear optimization tools, we demonstrate theoretically a maximum radiative heat-to-electricity efficiency of 6.4% and a corresponding output electrical power density of 0.39 W cm(-2) at temperature T = 1660 K when im...

We investigated SiC-based hydrogen gas sensors with metal-insulator-semiconductor (MIS) structure for high temperature process monitoring and leak detection applications in fields such as the automotive, chemical and petroleum industries. In this work, a thin tantalum oxide (Ta2O5) layer was exploited with the purpose of sensitivity improvement, because tantalum oxide has good stability at high...

Theoretical considerations that lead to the design of strong and ductile cobalt (Co)base alloys were discussed in part I of this series of articles.' It was hypothesized that the composition 40 Co-30 nickel (Ni)-30 chromium (Cr) is an acceptable compromise for the requirements of an alloy base. It also was found that tantalum (Ta) may have the qualities that are acceptable for an additional ele...