Influence of 2,3-Dihydroxyflavanone on Corrosion Inhibition of Mild Steel in Acidic Medium

The inhibition effect of 2,3-dihydroxyflavone on the corrosion of mild steel in 100-600 ppm aqueous hydrochloric acid solution has been investigated by weight loss and electrochemical impedance spectroscopy. The corrosion inhibition efficiency increases with increasing concentration and time. The effect of temperature on the corrosion behavior of mild steel in 1 M HCl with addition of inhibitor was studied at the temperature range of 300-330 K. UV-Vis, FTIR, and surface analysis (SEM) was also carried out to establish the corrosion inhibitive property of this inhibitor in HCl solution. The adsorption of this inhibitor on the mild steel surface obeys the Langmuir adsorption isotherm. Electrochemical studies reveal that the inhibitor is a cathodic type.     

Structural properties and enhanced photoelectrochemical performance of ZnO films decorated with Cu2O nanocubes

Combination of ZnO and Cu₂O semiconductors is remarkable for efficient photovoltaic cells and enhanced photoelectrochemical (PEC) performance due to the high electronic energy band alignment of these materials and their controllable electronic structure at the interface. This study reports on a systematic analysis of the effects of Cu₂O nanocube doping on the structural properties and PEC performance of ZnO films. ZnO samples doped with Cu₂O were prepared by a practical electrochemical method. Characterization of the materials was performed by XRD, Raman, FTIR spectroscopy and electrochemical techniques. The XRD, Raman, FTIR spectroscopy analyses indicated a single phase of ZnO for the lower Cu₂O deposition time, while a secondary phase of Cu₂O evolved for the 5 min deposition time. This study showed that ZnO doped with Cu₂O grown for 3 min had the best PEC performance. ZnO/Cu₂O photoelectrodes are recommended as an attractive, competitive and alternative candidate for advanced PEC sensing and this may be for the extended field of water splitting into oxygen and hydrogen under sunlight.     

Sol-gel synthesis,structural, morphological and magnetic properties of BaTiO3–BiMnO3 solid solutions

In this study, solid solutions of (1-x)BaTiO₃-xBiMnO₃ have been synthesized by an aqueous sol-gel method. It was determined that single-phase compounds can be obtained up to x = 0.6 and with further increase in percentage of BiMnO₃ component additional crystal phases were detected. Perovskite crystal structure was determined for all synthesized compounds regardless of chemical composition. Raman spectra of synthesized solid solutions showed gradual change of the shape with an increase of BiMnO₃ fraction. It was demonstrated that partial substitution of BaTiO₃ by BiMnO₃ led to the drastic growth of grains of the end products. Magnetization measurements showed that all BiMnO₃-containing samples are characterized by paramagnetic behavior. Clear correlation between magnetization values and composition of the materials was observed, magnetization values increased with increasing of BiMnO₃ content in solid solutions.     

Hybrid plasmonic label-free multi-analyte refractive index sensor

We propose a label-free refractive index sensor based on hybrid plasmonic resonator which consists of silver split-ring resonator and photonic waveguide. The finite difference time domain evaluation of the design exhibit strong field confinement at the center of the ring and introduces tunable and sensitive notches in the transmission spectrum. The planar tunable architecture which performs well over the range of micro fluid detection, holds the promise of developing multi-analyte label-free biosensors and compactness towards a complete on-chip integrated sensing system. The performance of the proposed refractive index sensor is evaluated by placing different analytes such as saline water and ethanol at the center of the hybrid plasmonic ring which exhibits sensitivity of 847.50 nm.RIU-1 with a figure of merit of 563.25 RIU-1.     

Enhancing power conversion efficiency of DSSC by doping SiO2 in TiO2 photo anodes

A simple, less time consuming, cost ineffective sol–gel method was used to synthesis TiO₂ nanoparticles (TiO₂) and TiO₂–SiO₂ nanocomposites (TiO₂–SiO₂) using titanium tetra isopropoxide as TiO₂ and silicic acid as SiO₂ precursors respectively. The synthesized nanocomposites were characterized by XRD, SEM, TEM, UV–visible, FTIR and BET analysis. The quantum confinement effect of TiO₂ and TiO₂–SiO₂ was confirmed by a blueshift observed in UV–visible spectra. The band observed at 950 cm⁻¹ in FTIR analysis confirmed the presence of Ti–O–Si bonds, the TEM analysis shows both the TiO₂ and TiO₂–SiO₂ were in nanometer size. The BET (Brunauer– Emmett–Teller) specific surface areas of the samples were 65 and 75 m²/g for TiO₂ and TiO₂–SiO₂ respectively. The power conversion efficiency (PCE) of the nanocomposites were studied by using Keithely electrometer and multimeter and it was found to be 2% and 2.5% for eosin-Y sensitized TiO₂ and TiO₂–SiO₂ nanocomposites respectively.     

Scheduling optimisation of flexible manufacturing systems using particle swarm optimisation algorithm

The increased use of flexible manufacturing systems (FMS) to efficiently provide customers with diversified products has created a significant set of operational challenges. Although extensive research has been conducted on design and operational problems of automated manufacturing systems, many problems remain unsolved. In particular, the scheduling task, the control problem during the operation, is of importance owing to the dynamic nature of the FMS such as flexible parts, tools and automated guided vehicle (AGV) routings. The FMS scheduling problem has been tackled by various traditional optimisation techniques. While these methods can give an optimal solution to small-scale problems, they are often inefficient when applied to larger-scale problems. In this work, different scheduling mechanisms are designed to generate optimum scheduling; these include non-traditional approaches such as genetic algorithm (GA), simulated annealing (SA) algorithm, memetic algorithm (MA) and particle swarm algorithm (PSA) by considering multiple objectives, i.e., minimising the idle time of the machine and minimising the total penalty cost for not meeting the deadline concurrently. The memetic algorithm presented here is essentially a genetic algorithm with an element of simulated annealing. The results of the different optimisation algorithms (memetic algorithm, genetic algorithm, simulated annealing, and particle swarm algorithm) are compared and conclusions are presented .     

Mechanism of improvement of resistance degradation in Y-doped BaTiO3 based MLCCs with Ni electrodes under highly accelerated life testing

The mechanism of improvement of resistance degradation in Y-doped BaTiO₃ based multilayer ceramic capacitors (MLCCs) with Ni electrodes has been studied using electrical measurement techniques, minor phase identification and the measurement of oxygen vacancy concentration. Admittance spectroscopy and thermally stimulated current measurements show the relaxation due to barium vacancy states caused by Y doping. The minor phase identification by XRD indicated those Y³⁺ substitutes for perovskite A-site. Oxygen vacancy concentration measurement indicated that Y decreases the oxygen ion vacancy concentration in BaTiO₃. These results suggest that Y³⁺ acts as a donor and creates barium vacancies, which compensate for the oxygen vacancies and thereby improve the resistance degradation.     

Experimental and simulation studies on the effect of suction opening orientation on solar vertical chimney

The zero energy building considered is a single storey building in Tiruchirappalli city retrofitted with various green features. This study investigated the effect of a suction opening orientation on a vertical solar chimney (VSC), integrated into a one-storey building. It was designed, manufactured and tested through selection of different suction openings for the entry of air, including right, left, front, back, both right and left and both front and back sides. Genetic algorithm (GA) calculates maximum air flow rate for a building with VSC for better suction opening, in Tiruchirappalli's dry, environmental conditions. GA is a useful technique for finding an improved suction opening specifically in the presence of a host of independent parameters which are large. The obtained results are related to fluid flow temperature distribution along the chimney, mass flow rate and air change per hour. The findings between the GA and the experimental results show sound agreement.     

A smooth co-ordination control for a hybrid autonomous power system (HAPS) with battery energy storage (BES)

The standalone hybrid power system constitutes a synchronous generator driven by a diesel engine, renewable energy source (wind) apart from a battery energy storage system. A coherent control strategy to regulate the voltage and frequency of the standalone grid is proposed in this paper. The system is simulated using Matlab/Simulink for preliminary validation and further tested on a laboratory prototype which involves a TMS320LF2407A DSP controller to digitally implement the control strategy. The dynamic behavior of the system is perused through the direct connection of an induction machine. The control strategy is verified for step changes in load and variation in wind power.     

Fabrication of metal-doped BiOI/MOF composite photocatalysts with enhanced photocatalytic performance

An octahedron-like metal-organic framework (MOF) was successfully synthesized by the ultrasound irradiation synthesis method. Meanwhile, a novel visible-light-driven Cu-doped BiOI/MOF composite photocatalyst was also synthesized by the microwave irradiation. MOFs, a new class of porous crystalline materials, have attracted tremendous attention considering their broad applications because MOF possesses the repeated crystalline structures and thereby improving the harvest of solar energy and transportation of charge carriers. In this article, the result has revealed that the appropriate modification of BIOI by incorporating MOF and copper could reach the maximum hydrogen yield under visible light irradiation. The hydrogen evolution for 10% v/v lactic acid and 0.30 g L^?1 of 3In/BiOI/4MOF composite photocatalyst had the maximum of 269.1 μmol h^?1 g^?1 for 6 h. However, as the overall time in a course of irradiation is prolongated until 48 h, 3Cu/BiOI/4MOF has the higher hydrogen evolution efficiency (7685.2 μmol) than that of 3In/BiOI/4MOF. Therefore, this study has substantially demonstrated to enhance the photocatalytic efficiency of BiOI photocatalyst using MOF and copper modified BiOI.