Nanoporous antimony-doped tin oxide (ATO) coatings with high surface area, optical transparency and electron transfer properties have been prepared using an interpenetrating inorganic-organic hybrid sol-gel approach. UV-Vis and X-ray photoelectron spectroscopic studies were carried out on the prepared materials in addition to the characterization of their microstructures with scanning electron microscopy, transmission electron microscopy, and nitrogen sorption experiments. Cyclic voltammetry (CV) and impedance spectroscopy were employed to characterize the electrochemical and electron transfer properties of the coatings in both acidic and neutral media with an Fe³⁺/Fe ²⁺ redox couple. The material had a specific surface area of over 90 m² g^-1 with a bimodal pore distribution with two distinctive peaks at ca. 8 and 40 nm. The electrochemical capacitance of the material was about 100 times as high as the value obtained for a commercially available nonporous fluorine-doped tin oxide (FTO) electrode. The estimated electron transfer rate of the former was three times larger than that of the FTO. The optical transparency, high surface area and high electron transfer rate of the nanoporous ATO coatings make the material well suited for diverse photoelectrochemical applications. © 2013 The Royal Society of Chemistry.

Sensing is central to the SenSys and related communities. However, fine-grained spatial sensing remains a challenge despite recent advancements, owing to cost, maintenance, among other factors. Thus, estimating the sensed phenomenon at unmonitored locations and strategically installing sensors is of prime importance. In this work, we introduce Polire - an open-source tool that provides a suite of algorithms for spatial interpolation and near-field passive sensor placements. We replicate two existing papers on these two tasks to show the efficacy of Polire. We believe that Polire is an essential step towards lowering entry barriers towards sensing and scientific reproducibility.

In this letter, we construct an effective field theory of gravity at large distances. We obtain to the leading order for large distances: a cosmological constant term and a logarithmic term in addition to the usual General Relativistic terms. The novel logarithmic term has important implications in explaining phenomena such as flat galactic rotation curves and stronger gravitational lensing than predicted that are generally attributed to the presence of dark matter.

Even though the Vertical Axis Wind Turbines (VAWT) are known to have lower efficiencies than the Horizontal Axis Wind Turbines (HAWT), their simple construction and the inherent design features qualify them as a viable and cheap options for low cost wind energy systems. Hence the VAWT proves extremely useful in rural sectors where it can be used extensively for electricity generation, pumping water and so on. Computational modeling of the flow fields in the vicinity of a VAWT for four different tip speed ratios of the turbine blade is the focus of this work. Here the flow is numerically computed using two different turbulence modeling approaches namely the Reynolds Averaged Navier-Stokes (RANS) with the Spalart-Allmaras turbulence model, which is popularly used for external aerodynamic analysis and the Large Eddy Simulation (LES) with the Wall-Adapting Local-Eddy Viscosity (WALE) model. The primary focus of this study is on the LES approach for turbulence modeling, where large scale motions are computed explicitly and the small scales of motion are modeled. This approach can accurately capture turbulent flow structures and effects of the large scale motions. Examination of the computed flow shows that the aerodynamic force coefficients are more accurately predicted by the LES flow models compared to those predicted by the RANS flow models. Although the computed variation of the aerodynamic force coefficients at different angular positions of the VAWT during a single revolution appears to be similar for both the flow models, noticeable differences in their magnitude are clearly observed. This work aims to support future studies such as the design optimization of a VAWT, layout of VAWT in a wind farm and extensive study of the effect of the turbine-wake interactions on the efficiency of the wind farm systems.