Scope of magnesium ceria nanocomposites for mandibular reconstruction: Degradation and biomechanical evaluation using a 3-dimensional finite element analysis approach.

Magnesium/Ceria nanocomposites (Mg/xCeO2 NCs (x = 0.5 %, 1 % and 1.5 %)) prepared by using powder metallurgy and microwave sintering method are assessed for their corrosion rate for a period of 28 days. As per the immersion tests results, the addition of ceria nanoparticles to pure Mg, brought about a noteworthy improvement to corrosion resistance. A corrosion rate of approximately 0.84 mm/year for Mg/0.5CeO2 and 0.99 mm/year for Mg/1.0CeO2 nanocomposites were observed. Another aspect of the study involves employing the simulation method i.e. finite element analysis (FEA) to compare the stress distribution in magnesium-ceria nanocomposite based screws and circular bars especially for Mg/0.5CeO2 and Mg/1.0CeO2. Further, the simulation also gives a perception of the impact of masticatory forces, the biting force and shear stress exerted on the Mg/0.5CeO2 and Mg/1.0CeO2 based screws. The simulations results show that the screws showed an acceptable level of stresses for a biting force up to 300 N. The circular bar as well kept its stresses at acceptable levels for the same load of 300N. The shear stress results indicated that a biting force up to 602 N can be safely absorbed by Mg/0.5CeO2 screw. The comprehensive approach allows for a better understanding of the corrosion behavior, stress distribution, and mechanical properties of the Mg/CeO2 nanocomposites, enabling the development of effective temporary implants for craniofacial trauma fixation that can withstand normal physiological forces during mastication. The study reported in this paper aims to target Mg/xCeO2 NCs for temporary implants for craniofacial trauma fixation.

Combined Effect of Operating Parameters and Nanoparticles on the Performance of a Diesel Engine: Response Surface Methodology-Coupled Genetic Algorithm Approach.

This paper's goal is to ascertain the optimum input parameters and nanoparticle concentrations for least emission and better performance by utilizing the genetic algorithm (GA) and response surface methodology (RSM) in a single-cylinder diesel engine running with 20% blend of biodiesel derived from Manilkara zapota seeds. Experiments to be conducted on the engine were designed with a central composite design (CCD) with input parameters of loads (20-100%), nanoparticle concentrations (NPCs, 0-80 ppm), compression ratios (CRs, 16.5-18.1), injection pressures (IPs, 190-230 bar), and injection timings [ITs, 17-29° bTDC (before top dead center)], and the engine response was recorded. The comparative analysis of optimization tools RSM and GA was employed for finding the ideal setting of engine input parameters and nanoparticle concentrations based on the maximization of performance [brake thermal efficiency (BTE) and brake-specific fuel consumption (BSFC)] and minimization of emissions [(hydrocarbon (HC), carbon monoxide (CO), and nitrogen oxides (NOx)]. The best result was obtained by the RSM method. The optimized input parameters were recorded at a load of 59.36%, an NPC of 80 ppm, a CR of 18.1, an IP of 192.02 bar, and an IT of 18.62° bTDC. At these optimized settings, the performance and emissions were 32.4767% BTE, 0.1905 kg/kW h BSFC, 26.8436 ppm HC, 0.0272% CO, and 83.854 ppm NOx emissions from the engine. The developed model was validated through a confirmatory experiment, and the prediction error was within 8%. Thus, the applied model is appropriate for improving the engine's emission and performance attributes.

Experimental study of solar energy-based water purifier of single-slope type by incorporating a number of similar evacuated tubular collectors.

This research paper deals with the experimental investigation of solar energy-based water purifier (SEBWP) of single-slope type by incorporating N similar evacuated tubular collectors (ETCs) having series connection. Experimental investigation has been done for a year from August 2018 to July 2019. MATLAB has been used for evaluating performance parameters of the system followed by the validation of these results with their experimental values. A fair agreement has been found between theoretical and experimental values. Values of correlation coefficients for condensing glass temperature, water temperature, and water yield have been found to be 0.9932, 0.9928, and 0.9951 respectively. Further, energy metrics, productivity, cost of producing 1 kg of fresh water, and exergoeconomic and enviroeconomic parameters have been evaluated. Values of energy payback time, per kilogram cost of producing fresh water and exergy loss per unit Rs. have been evaluated to be 1.72 years, Rs. 0.95/kg, and 0.128 kWh/Rs. respectively.

An investigation on dissimilarity of mass flow rate and N on exergo-enviro-economic parameters for solar still of single slope type integrated with N similar PVT flat plate collectors having series connection.

This paper investigates analytically the effect of dissimilarity of mass flow rate [Formula: see text] and number of collectors (N) on exergo-enviro-economic parameters for solar still of single slope type integrated with N similar photovoltaic thermal flat plate collectors having series connection (NPVTFPC-SS) keeping water depth as 0.14 m. All four kinds of weather conditions for New Delhi have been taken for the computation of different parameters. All relevant equations obtained using energy balance equations for all components of the system have been fed to a computer code inscribed in MATLAB-2015a for computing different parameters. The computation of different relevant parameters has been performed for various values of [Formula: see text] and N while keeping water depth as constant to know the effect of variation of [Formula: see text] and N on exergo-enviro-economic parameters for NPVTFPC-SS. It has been concluded that the value of carbon credit earned, enviroeconomic and exegoeconomic parameters, and productivity diminishes with the enhancement in [Formula: see text] at given N. The optimum value of N for given value of [Formula: see text] has been found to be 10 from exergoeconomic parameter viewpoint and 6 from productivity viewpoint.

Development of rare-earth oxide reinforced magnesium nanocomposites for orthopaedic applications: A mechanical/immersion/biocompatibility perspective.

Magnesium-Zinc based nanocomposites containing cerium oxide nanoparticles were developed in the present work. A systematic study on their microstructure, mechanical properties, in vitro degradation behaviour, and cytotoxicity are presented. It was found that the developed nanocomposites exhibited excellent strength and toughness that are superior to the commercially available magnesium alloys. From corrosion perspective, nanocomposites exhibited reduced pH increase compared to pure Mg with Mg-0.5Zn/0.5CeO2 showing the least corrosion rate. Moreover, the developed nanocomposites exhibited no cytotoxicity to MC3T3-E1 pre-osteoblast cells. Based on the above findings, the feasibility of Mg-Zn/CeO2 nanocomposites for use as orthopaedic implants is systematically discussed. This study provides an insight into the development of new high-performance Mg alloy-rare earth oxide (REO)-based nanocomposites with superior mechanical properties and corrosion resistance while effectively avoiding the possible standing toxic effect of RE elements.

Surface Topography Analysis of Mg-Based Composites with Different Nanoparticle Contents Disintegrated Using Abrasive Water Jet.

This study investigated the effect of abrasive water jet kinematic parameters, such as jet traverse speed and water pressure, on the surface of magnesium-based metal matrix nanocomposites (Mg-MMNCs) reinforced with 50 nm (average particle size) Al2O3 particles at concentrations of 0.66 and 1.11 wt.%. The extent of grooving caused by abrasive particles and irregularities in the abrasive waterjet machined surface with respect to traverse speed (20, 40, 250 and 500 mm/min), abrasive flow rate (200 and 300 g/min) and water pressure (100 and 400 MPa) was investigated using surface topography measurements. The results helped to identify the mode of material disintegration during the process. The nanoindentation results show that material softening was decreased in nanocomposites with higher reinforcement content due to the presence of a sufficient amount of nanoparticles (1.11 wt.%), which protected the surface from damage. The values of selected surface roughness profile parameters-average roughness (Ra), maximum height of peak (Rp) and maximum depth of valleys (Rv)-reveal a comparatively smooth surface finish in composites reinforced with 1.11 wt.% at a traverse speed of 500 mm/min. Moreover, abrasive waterjet machining at high water pressure (400 MPa) produced better surface quality due to sufficient material removal and effective cleaning of debris from the machining zone as compared to a low water pressure (100 MPa), low traverse speed (5 mm/min) and low abrasive mass flow rate (200 g/min).