Detecting and Mitigating Selfish Primary Users in Cognitive Radio

Wireless Personal Communications - In today’s world, Cloud computing based health cloud is an effective platform for enhancing e-health productivity, i.e., healthcare professionals can...     

Effect of CNG flow rate on the performance and emissions of a Mullite-coated diesel engine under dual-fuel mode

On the diesel engines that are used to generate power in transportation and industries, many researchers have to deal with major problems of smoke emissions while extracting higher efficiency. There are many studies which reported the exhaust emission reduction strategies from diesel engines by applying new combustion methods that are capable of mitigating the formation of harmful emissions. One of the methods to reduce the exhaust emissions in diesel engines is to use the dual-fuel combustion mode. In this study, an attempt has been made to evaluate the effect of thermal barrier coating (TBC) on the dual-fuel engine and for this, experiments are carried out on a single-cylinder direct-injection diesel engine under dual-fuel and low heat rejection mode with compressed natural gas (CNG) as gaseous fuel. Engine components that are exposed to the combustion are coated with Mullite (3Al₂O₃-2SiO₂) TBC. Diesel at 200 bar injector opening pressure was used as pilot fuel and CNG at different flow rates (5, 10 and 15 litres per minute) was inducted into the combustion chamber through inlet manifold as main fuel. Experimental results show that the coating of TBC on the engine components has a positive effect on the performance emissions of the dual-fuel test engine. Brake specific fuel consumption (BSFC) was found improved significantly at all flow rates of CNG with coated engine. Emissions on the other hand were also noticed to be on the lower side with the coated engine except NO_x. Smoke emissions were significantly reduced with coated CNG operation of the test engine at all flow rates.     

POSS-based luminescent hybrid material for enhanced photo-emitting properties

In this present work, we have developed a novel POSS type monomer ligand “2,6-pyridinediamine-bis-(propanylheptaisobutyl POSS)” (PDC-POSS) and utilized in the preparation of potential luminescent hybrid complex Eu-PDC-POSS with an inner transition metal ion Eu³⁺. The solubility and photo-emitting properties of new Eu-PDC-POSS hybrid material were studied. The precursor PDC-POSS was synthesized by treating (3-aminopropyl)heptaisobutyl POSS with PDC (2,6-pyridinedicarboxylic acid chloride), and then coordinated with Eu³⁺ using europium nitrate to afford Eu-PDC-POSS hybrid material. The europium-doped hybrid material was characterized using fourier transform infrared spectroscopy, and scanning electron microscopy along with energy dispersive X-ray analysis. The photo emitting properties were studied using a fluorescence spectrophotometer in which, the results showed enhancement in red emission peak at 618 nm for Eu-PDC-POSS, when compared to that of a known solgel-based material Eu-PDC-solgel.     

Experimental realization of ‘universal homodyne tomography’ with a single local oscillator

We report preliminary experimental measurement of the twin-beam quantum state via optical homodyne tomography using a single local oscillator. The experiment is a realization of the recently reported ‘universal homodyne tomography’ technique. The results agree well with theoretical predictions and reveal the non-classical photon-number correlation between the signal and idler photons of the twin-beam state.     

Covalent Complex of DNA and Bacterial Topoisomerase: Implications in Antibacterial Drug Development

A topoisomerase-DNA transient covalent complex can be a druggable target for novel topoisomerase poison inhibitors that represent a new class of antibacterial or anticancer drugs. Herein, we have investigated molecular features of the functionally important Escherichia coli topoisomerase I (EctopoI)-DNA covalent complex (EctopoIcc) for molecular simulations, which is very useful in the development of new antibacterial drugs. To demonstrate the usefulness of our approach, we used a model small molecule (SM), NSC76027, obtained from virtual screening. We examined the direct binding of NSC76027 to EctopoI as well as inhibition of EctopoI relaxation activity of this SM via experimental techniques. We then performed molecular dynamics (MD) simulations to investigate the dynamics and stability of EctopoIcc and EctopoI-NSC76027-DNA ternary complex. Our simulation results show that NSC76027 forms a stable ternary complex with EctopoIcc. EctopoI investigated here also serves as a model system for investigating a complex of topoisomerase and DNA in which DNA is covalently attached to the protein.     

Polyaniline–13X zeolite composite‐supported platinum electrocatalysts for direct methanol fuel cell applications

We successfully synthesized 13X zeolite using a hydrothermal method. Then, composites of polyaniline (PANI) with 13X zeolite and PANI–13X with platinum were prepared by chemical oxidative polymerization and chemical reduction, respectively. Field emission scanning electron microscopy, X‐ray diffraction, Raman spectroscopy and Brunauer–Emmett–Teller techniques were used to characterize the PANI–Pt and PANI–Pt–13X composites. Further, the electrocatalytic activity towards methanol oxidation of the synthesized catalysts was explored using cyclic voltammetry in 1 mol L^?1 CH₃OH + 0.5 mol L^?1 H₂SO₄ solution. From the obtained results, PANI–Pt–13X shows superior performance compared to PANI–Pt towards methanol oxidation and electrical conductivity. Hence, the 13X zeolite‐incorporated PANI–Pt composite could be an efficient catalyst for direct methanol fuel cell applications. © 2019 Society of Chemical Industry     

Morphology controlled synthesis of polyaniline nanostructures using swollen liquid crystal templates

Preparation of zero‐dimensional and one‐dimensional nanostructures of polyaniline (PANI) were achieved by using swollen liquid crystals (SLCs) as ‘soft' templates. The monomer (aniline) was first entrapped in SLCs by replacing the oil phase (cyclohexane) with a mixture of aniline and cyclohexane. Zero‐dimensional nanostructures of PANI were obtained by thorough mixing of APS with the mesophases. One‐dimensional nanostructures were prepared by allowing slow diffusion of APS through the mesophase. PANI nanostructures were extracted from the mesophase and were characterized by UV‐visible spectroscopy, FTIR spectroscopy, powder X‐ray diffraction, atomic force microscopy, scanning electron microscopy (SEM), and conductivity measurements. A plausible mechanism for the formation of the nanostructures has been proposed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40800.     

An onsite demonstration and validation of LiDAR technology for wind energy resource assessment

The investigation of wind resource at higher heights is very crucial in planning wind power project. Normally, this involves the installation of a high and costly meteorological mast with a cup anemometer and wind vanes. This investigation uses the new ground-based remote-sensing technique Light Detection and Ranging (LiDAR) to investigate the wind resource at higher heights. This paper describes the LiDAR technology principle and examines the potential of LiDAR measurement to estimate the wind resource at higher heights by conducting a measurement campaign at Tamil Nadu, India. The wind statistics were determined using the 10?min average time-series wind data monitored by ZephIR LiDAR. These include the Weibull parameters, daily mean wind speed, wind power density, wind energy density, vertical wind speed profile and capacity factor. The investigation reveals that the vertical wind speed profile measured from the LiDAR system has approximate closer values to the standard meteorological measurement.