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The wastewater released from industries contains many harmful materials like organic dyes and toxic metal ions which badly affect our environment. Nanotechnology is one of the unique approaches to reducing these chemicals. In current research work monometallic ZnO and Co-ZnO bimetallic NPs were synthesized from Brassica rapa leave’s extract and then these were employed for the elimination of methylene blue (MB) and metal ions of Cu (II). Characterization was done by several analytical techniques such as EDX, FTIR, UV–Visible spectroscopy, SEM and XRD. The average diameter of ZnO and Co-ZnO BMNPs was found to be 32.94 nm and 13.82 nm assessed by XRD analysis. The SEM investigation revealed that the produced NPs had a spherical shape. Three distinct methods have opted to determine the antioxidant potential of synthesized NPs. Different factors like pH, contact time, NPs conc., dye conc. and temperature were studied for the elimination of dye while for the eradication of Cu (II) ions; pH, contact time, NPs conc. and adsorbate doses were studied. Adsorption isotherm and kinetic studies were employed for MB and Cu (II) ions elimination while thermodynamic studies were also done for the elimination of MB.

In this study, green synthesis of monometallic (Ag) and bimetallic (Ag-Ni) nanoparticles is carried out. UV-Visible spectra illustrated peaks at 463 and 429 nm for monometallic and bimetallic nanoparticles. FTIR spectra analysis revealed the presence of different functional groups. SEM and EDX elaborated on the morphology and indicate the presence of respective elemental peaks. XRD data calculations predicted the size of monometallic and bimetallic to be 42 and 25 nm. In the end, the biosynthesized nanoparticles are used as a spectrophotometric probe for the determination of cupric ions. Different parameters are studied and optimized on a standard aqueous solution. Monometallic nanoparticles showed an optimum response in a slightly alkaline medium within 12.5 min of contact time for 8 μM analyte concentration. While bimetallic nanoparticles attained this target in a shorter contact time with a higher concentration value. Then these optimized conditions are utilized for the determination of cupric ions in real water samples.

Nowadays, for environmental remediation, photocatalytic process involving graphene-based semiconductors is considered a very promising oxidation process for water treatment. In the present study, nanocomposite (Cu/Ni/rGO) has been synthesized by Dypsis lutescens leaf extract. Characterization of the sample was carried out by UV-visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Different parameters like contact time, nanocatalyst amount, dye concentration, effect of temperature. and pH factor were optimized to examine the maximum removal efficiency for dyes rhodamine B and alizarine R with and without visible light source. In both cases, i.e., with or without light, maximum removal was observed at 20 mg of nanocatalyst for 5 ppm concentration of both dyes at 45 °C temperature and pH 10 for rhodamine B and pH 4 for alizarine R, respectively with a 20 min contact time. Maximum removal of dyes 93% rhodamine B and 91% alizarine R were observed under a tungsten lamp as compared to without a tungsten lamp, i.e., 78% of RhB and 75% of AR from mixture solution of these dyes. To assess the rate of reaction, spontaneity, and nature of reaction thermodynamics, kinetics and adsorption isotherms were studied. Thermodynamic values indicated that both dyes depicted endothermic and spontaneous degradation processes. Isotherm data fitted best to a Freundlich isotherm, while results of kinetic studies of both dyes followed the pseudo 2nd order kinetic equation. In the end, scavenging radical studies concluded that hydroxyl radicals were the main active specie involved in the photocatalytic degradation process, and regeneration experiments resulted that Cu/Ni/rGO nanocomposites were re-utilized for about four times.

In this work, green synthesized cobalt monometallic and cobalt–zinc bimetallic NPs were prepared by bioreduction of metallic salts with Cymbopogan citratus plant extract. Biosynthesized cobalt nanoparticles (NPs) and cobalt–zinc bimetallic NPs were characterized using diverse techniques such as FTIR, UV-Visible spectroscopy, SEM, XRD, and EDX analyses. UV-visible spectra for green-synthesized cobalt monometallic and cobalt–zinc bimetallic NPs were in the range between 300 to 350 nm, which confirmed the formation of stable monometallic and bimetallic NPs. The average particle size of CoNPs calculated by XRD analysis was found to be 22.77 nm and that of Co-Zn BMNPs was 14.8 nm. Different functional groups in the Cymbopogan citratus plant extract, which served as a reducing and stabilizing agent for NPs, were identified by FTIR spectra. Cobalt NPs and cobalt–zinc bimetallic NPs were used in the evaluation of antioxidant, anti-inflammatory, and dye degradation activity. Green-synthesized cobalt monometallic NPs and cobalt–zinc bimetallic NPs exhibited excellent antioxidant activity with the scavenging of DPPH free radicals. Green synthesized cobalt NPs and cobalt–zinc bimetallic NPs were utilized for the removal of methylene blue (MB) dye. Different parameters such as the effect of temperature, pH, and dye concentration on adsorbent doses were analyzed and optimized. The best dye removal percentage was obtained with Co-Zn BMNPs compared with CoNPs. Cobalt NPs and cobalt–zinc bimetallic NPs did not display good anti-inflammatory activity because of the presence of secondary metabolites which inhibited them to react with proteins.

The demand for clean and sustainable alternative energy resources is linearly increasing day by day due to the prevailing electricity crisis. Small-scale energy harvesting is considered a sustainable way to generate clean energy. Advanced energy solar cells, mainly dye-sensitized solar cells use solar energy and convert it into electrical energy. Similarly, MEMS-based piezoelectric materials are used to convert mechanical energy into electrical energy. For these applications, zinc oxide is considered one of the most suitable materials with high conductive, tunable band gap, and piezoelectric properties. However, altering these properties can be carried out by the addition of metal and other materials. Various research work has been carried out to study the addition of conductive metal as a dopant to alter the properties of zinc oxide. In this study, Strontium has been doped in ZnO to form a nanostructure for application in DSSC and microelectromechanical systems (MEMS) energy harvesters. Analysis has been conducted using the simulation and fabrication method. The results show that the doping and the pore size of the substrate (Anodic Aluminum oxide membrane) largely affect the output voltage and current. The difference between the simulated and experimental results was less than 1%, which shows the accuracy of the simulation. Tuning of the band gap can be observed by the addition of Sr in the ZnO nanostructure. For microelectromechanical systems energy harvesters, Sr-doped ZnO nanostructures deposited on anodic aluminum oxide show 7.10 mV of voltage and 1.11 uA of current output. The addition of Sr doping in ZnO shows the improvement in the generated current and voltage for the energy harvester and the improvement in overall power conversion efficiency for dyesensitized solar cells. MEMS-based energy harvesting devices and low-cost advanced solar cells are promising to improve the efficiency of energy generation at a small scale. [ABSTRACT FROM AUTHOR]

The title compound, C7H8O4, isolated from Opuntia dillenii Haw (Cactaceae), is almost planar [maximum deviation of 0.027 (2) Å] except for the H atoms of the methylene and methyl groups. The crystal packing is stabilized by C—H...O and O—H...O intermolecular hydrogen bonds, resulting in the formation of a three-dimensional network.

Conventionally, a flexural plastic hinge is designed and detailed at the core wall base and coupling beams ends to control the seismic responses. This strategy is based on allowing the damage to be concentrated on main structural components. To avoid such damage, an alternative strategy using energy dissipating devices (EDDs) such as buckling restrained braces (BRBs) is being studied and implemented nowadays. In this study, effect of BRBs locations on forty- (40-) story high-rise RC core wall case study building has been studied in detail using Nonlinear Response History Analysis (NLRHA) for seven spectrally matched ground motions. BRBs have been installed at critical locations identified with respect to the maximum DBE elastic modal racking shear deformation demands and force (shear and moment) demands in three different options. The force, deformation, and energy demands on structural components are compared for conventional design and different options of BRBs. The comparison with conventional design shows that BRBs not only are effective for reducing shear force demand along wall height, bending moment demand at mid height, and deformation demands by 10%, 45%, and 45%, respectively, but significantly reduce the rotation and energy demands in the core wall by 90% and 250%, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the design, modeling and simulation of nanogenerator. Nano structure based energy generator is used to convert the small physical motion into electrical energy such as body part motion, heart beating, vibrating parts of the factory machines walls, floors and thrilling parts of transports. In the present study, two input parameters like force and thickness and two output parameters like voltage and current have been considered and simulation was performed using the fuzzy logic technique. This approach helps to optimize the durable, accurate and efficient nano-generator. Basic Madami model of the fuzzy logic is used for calculations. The input and output parameters have been assigned three membership functions (MFs). The device works according to the instructions well-defined in the fuzzy inference system (FIS). On the basis of simulation we observed operational diagrams. Surface viewer were used to observe the curves and to analyse the results of all defined MFs. Diverse rules by making various group were defined in MATLAB rule managing editor and AND logic is adopted for simulation. Mamdani's expression is used for the calculation of the outputs. The calculation based results and simulated results show very littlie variation for fuzzy logic (FL) nanogenerator. There is present 1% error in simulated and theoretical values that shows that FL based nano-generator controller is very efficient to harvest the energy from nano structure based device. [ABSTRACT FROM AUTHOR]

This paper presents the design and simulation of MEMS based energy harvester controller. Energy harvesting from physical motion such as finger motion, heart beating, walking and running are becoming so important now-a-days. In this study outputs voltage and current of the MEMS based energy harvester can be controlled by using fuzzy logic based control system. A new way of controlling the outputs by changing the inputs has been proposed in this study. The system has been developed in MATLAB using fuzzy logic Mamdani model.Two inputs pressure and area have been selected. The three membership functions to the input parameters have been assigned. The two outputs like voltage and current are selected for output power. Three membership functions are also assigned to the outputs. The system works according to the rules defined in the fuzzy inference system (FIS). The results according to suggested rules belonging to assigned MFs have been displayed in surface viewer.Different rules of combinations were defined in MATLAB rule editor and we used AND logic for simulation. The rsults obtained from fuzzy logic controller have been verified by using Mamdani's formula for specific values of the inputs and the outputs. As there is only 1% error for both the outputs, current and voltage, this shows that the system performs very well. [ABSTRACT FROM AUTHOR]

This paper presents the design and simulation of flow controller of dams gates using fuzzy logic based control system. A new way of controlling the opening and closing of dam gates has been proposed in this study. The system has been developed firstly in MATLAB using fuzzy logic Mamdani model and then the system is checked by developing a simple C language code using Microcontroller. Two input parameters have been selected like water level and water speed. The three membership functions to these parameters have been assigned. The one output parameter is selected as flow controller. Three membership functions are also assigned to the output. In this study the system works according to the rules defined in the fuzzy inference system. The simulation results are compared with the calculated results of mamdani formula. A pseudo code is developed from the rules defined in the FIS and code is generated in C language. The C language code is then burnt in the Atmel 89C51 microcontroller and a simple control circuit is developed to check the software results on practical basis. The basic concept of the study is that this system will show extreme response on extreme condition otherwise it will show normal results. When both inputs are in the higher (high water level and fast speed) region the output results will also be in the higher region (dam gates full open). This system showed great efficiency and robustness as it can be easily seen from the observations. This system is much different from the conventional systems as it involves simple microcontroller circuit. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, design and simulation of piezoelectric actuator has been presented. The fluid flow rate using MP6 PTZ micropump for artificial kidney has also been studied. The piezoelectric actuator consists of silicon membrane and piezoelectric disk. Finite element method (FEM) using ANSYS has been used for simulation. The maximum displacement 3.6μm occurs in the silicon membrane at the center at applied 100V for frequency 200Hz. Fluid flow rate using commercially available PZT MP6 micropump has been investigated for artificial kidney system. DI water and heparin have been considered as fluid during experiments. The flow rate has been controlled by adjusting the voltage and frequencies. Experimental results show that the MP6 pump is suitable for heparin infusion in our ongoing project for wearable artificial kidney. The presented research work provides useful information and predicted data to develop the optimized design of piezoelectric actuator to develop micropump for artificial kidney system. [Copyright &y& Elsevier]

In this research work, Polydimethylsiloxane (PDMS) has been used for the fabrication of microchannels for biomedical application. Under the internet of things (IoT)-based controlled environment, the authors have simulated and fabricated bio-endurable, biocompatible and bioengineered PDMS-based microchannels for varicose veins implantation exclusively to avoid tissue damaging. Five curved ascending curvilinear micro-channel (5CACMC) and five curved descending curvilinear micro-channels (5CDCMC) are simulated by MATLAB (The Math-Works, Natick, MA, USA) and ANSYS (ANSYS, The University of Lahore, Pakistan) with actual environments and confirmed experimentally. The total length of each channel is 1.6 cm. The diameter of both channels is 400 µm. In the ascending channel, the first to fifth curve cycles have the radii of 2.5 mm, 5 mm, 7.5 mm, 10 mm, and 2.5 mm respectively. In the descending channel, the first and second curve cycles have the radii of 12.5 mm and 10 mm respectively. The third to fifth cycles have the radii of 7.5 mm, 5 mm, and 2.5 mm respectively. For 5CACMC, at Reynolds number of 185, the values of the flow rates, velocities and pressure drops are 19.7 µLs−1, 0.105 mm/s and 1.18 Pa for Fuzzy simulation, 19.3 µLs−1, 0.1543 mm/s and 1.6 Pa for ANSYS simulation and 18.23 µLs−1, 0.1332 mm/s and 1.5 Pa in the experiment. For 5CDCMC, at Reynolds number 143, the values of the flow rates, velocities and pressure drops are 15.4 µLs−1, 0.1032 mm/s and 1.15 Pa for Fuzzy simulation, 15.0 µLs−1, 0.120 mm/s and 1.22 Pa for ANSYS simulation and 14.08 µLs−1, 0.105 mm/s and 1.18 Pa in the experiment. Both channels have three inputs and one output. In order to observe Dean Flow, Dean numbers are also calculated. Therefore, both PDMS channels can be implanted in place of varicose veins to have natural blood flow. [ABSTRACT FROM AUTHOR]

The smart grid (SG) has emerged as a key enabling technology facilitating the integration of variable energy resources with the objective of load management and reduced carbon-dioxide (CO 2 ) emissions. However, dynamic load consumption trends and inherent intermittent nature of renewable generations may cause uncertainty in active resource management. Eventually, these uncertainties pose serious challenges to the energy management system. To address these challenges, this work establishes an efficient load scheduling scheme by jointly considering an on-site photo-voltaic (PV) system and an energy storage system (ESS). An optimum PV-site matching technique was used to optimally select the highest capacity and lowest cost PV module. Furthermore, the best-fit of PV array in regard with load is anticipated using least square method (LSM). Initially, the mathematical models of PV energy generation, consumption and ESS are presented along with load categorization through Zero and Finite shift methods. Then, the final problem is formulated as a multiobjective optimization problem which is solved by using the proposed Dijkstra algorithm (DA). The proposed algorithm quantifies day-ahead electricity market consumption cost, used energy mixes, curtailed load, and grid imbalances. However, to further analyse and compare the performance of proposed model, the results of the proposed algorithm are compared with the genetic algorithm (GA), binary particle swarm optimization (BPSO), and optimal pattern recognition algorithm (OPRA), respectively. Simulation results show that DA achieved 51.72% cost reduction when grid and renewable sources are used. Similarly, DA outperforms other algorithms in terms of maximum peak to average ratio (PAR) reduction, which is 10.22%. [ABSTRACT FROM AUTHOR]