Predicted Performance Bounds of Thermochromism Assisted Photon Transport for Efficient Solar Thermal Energy Storage

Efficient storage of solar thermal energy is still one of the major bottlenecks in realizing dispatchable solar thermal systems. Present work is a significant step in this direction, wherein, we propose, thermochromism assisted photon transport based optical charging for efficient latent heat storage. Seeding thermochromic nanoparticles into the phase change material (PCM) allows for dynamic control of PCM's optical properties - aiding deeper penetration of photons and hence significantly enhancing the photon-nanoparticle interactions. Moreover, carefully tailoring of transition temperature near the melting temperature allows for efficient non-radiative decay of the absorbed photon energy and that too under nearly thermostatic conditions. In particular, the present work serves to develop a mechanistic opto-thermal theoretical modelling framework to compute melting front progression, latent heat storage and sensible heat discharging capacities pertinent to thermochromism assisted photon transport. Moreover, to truly assess and quantify the benefits of the aforementioned charging route, a host of other possible charging routes (viz., thermal and non-thermochromic optical charging) have also been dealt with. Detailed analysis reveals that relative to the thermal charging route, thermochromism assisted optical charging offers significant enhancements in terms of melting front progression (approximately 152%) and latent heat storage capacity (approximately 167%). Overall, thermochromism assisted photon transport is a synergistic approach which allows for simultaneous collection and storage of solar energy at accelerated rates without requiring the PCM to be heated to high temperatures.Comment: 28 pages, 17 figures, to be submitted to a Journa

The Trials and Tribulations of Structure Assisted Design of KCa Channel Activators.

Calcium-activated K+ channels constitute attractive targets for the treatment of neurological and cardiovascular diseases. To explain why certain 2-aminobenzothiazole/oxazole-type KCa activators (SKAs) are KCa3.1 selective we previously generated homology models of the C-terminal calmodulin-binding domain (CaM-BD) of KCa3.1 and KCa2.3 in complex with CaM using Rosetta modeling software. We here attempted to employ this atomistic level understanding of KCa activator binding to switch selectivity around and design KCa2.2 selective activators as potential anticonvulsants. In this structure-based drug design approach we used RosettaLigand docking and carefully compared the binding poses of various SKA compounds in the KCa2.2 and KCa3.1 CaM-BD/CaM interface pocket. Based on differences between residues in the KCa2.2 and KCa.3.1 models we virtually designed 168 new SKA compounds. The compounds that were predicted to be both potent and KCa2.2 selective were synthesized, and their activity and selectivity tested by manual or automated electrophysiology. However, we failed to identify any KCa2.2 selective compounds. Based on the full-length KCa3.1 structure it was recently demonstrated that the C-terminal crystal dimer was an artefact and suggested that the "real" binding pocket for the KCa activators is located at the S4-S5 linker. We here confirmed this structural hypothesis through mutagenesis and now offer a new, corrected binding site model for the SKA-type KCa channel activators. SKA-111 (5-methylnaphtho[1,2-d]thiazol-2-amine) is binding in the interface between the CaM N-lobe and the S4-S5 linker where it makes van der Waals contacts with S181 and L185 in the S45A helix of KCa3.1

A Review on Impulse RADAR

RADAR plays a vital role in military applications since its origin in the 2nd world war. Recently it has been used in surface inception, health monitoring, infrastructure health monitoring, etc. In these applications, Ultra-wideband RADAR systems are more popular than traditional RADAR systems. Impulse RADAR is a special kind of ultra-wideband RADAR, which is mostly used for surface penetration, through-wall imaging, antimissile detection, anti-stealth technology, etc. because of its high resolution and low center frequency. Out of all these applications, impulse RADAR has been used intensively as a ground-penetrating RADAR for the detection of land mines, underlying pipelines, buried objects, etc. This report has attempted to provide the steps for designing the impulse ground penetrating RADAR (GPR) as well as provides the value of crucial parameters required in the design process of commercial GPR systems