scholarly journals Modeling, Optimization and Performance Evaluation of TiC/Graphite Reinforced Al 7075 Hybrid Composites Using Response Surface Methodology

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4703
Author(s):  
Mohammad Azad Alam ◽  
Hamdan H. Ya ◽  
Mohammad Yusuf ◽  
Ramaneish Sivraj ◽  
Othman B. Mamat ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Hybrid Composites ◽  
Compaction Pressure ◽  
Physical And Mechanical Properties ◽  
Microstructural Characterization ◽  
X Ray ◽  
Weight Percentage ◽  
Al 7075 ◽  
Independent Parameters

The tenacious thirst for fuel-saving and desirable physical and mechanical properties of the materials have compelled researchers to focus on a new generation of aluminum hybrid composites for automotive and aircraft applications. This work investigates the microhardness behavior and microstructural characterization of aluminum alloy (Al 7075)-titanium carbide (TiC)-graphite (Gr) hybrid composites. The hybrid composites were prepared via the powder metallurgy technique with the amounts of TiC (0, 3, 5, and 7 wt.%), reinforced to Al 7075 + 1 wt.% Gr. The microstructural characteristics were investigated by optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) elemental mapping. A Box Behnken design (BBD) response surface methodology (RSM) approach was utilized for modeling and optimization of density and microhardness independent parameters and to develop an empirical model of density and microhardness in terms of process variables. Effects of independent parameters on the responses have been evaluated by analysis of variance (ANOVA). The density and microhardness of the Al 7075-TiC-Gr hybrid composites are found to be increased by increasing the weight percentage of TiC particles. The optimal conditions for obtaining the highest density and microhardness are estimated to be 6.79 wt.% TiC at temperature 626.13 °C and compaction pressure of 300 Mpa.

scholarly journals Efficient Removal of Levofloxacin by Activated Persulfate with Magnetic CuFe2O4/MMT-k10 Nanocomposite: Characterization, Response Surface Methodology, and Degradation Mechanism

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3583
Author(s):  
Junying Yang ◽  
Minye Huang ◽  
Shengsen Wang ◽  
Xiaoyun Mao ◽  
Yueming Hu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Response Surface Methodology ◽  
Response Surface ◽  
Photoelectron Spectroscopy ◽  
Degradation Mechanism ◽  
Sol Gel ◽  
Combustion Method ◽  
Copper Ferrite ◽  
X Ray ◽  
Rsm Model

In this study, a magnetic copper ferrite/montmorillonite-k10 nanocomposite (CuFe2O4/MMT-k10) was successfully fabricated by a simple sol-gel combustion method and was characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), the Brunner–Emmett–Teller (BET) method, vibrating sample magnetometer (VSM), and X-ray photoelectron spectroscopy (XPS). For levofloxacin (LVF) degradation, CuFe2O4/MMT-k10 was utilized to activate persulfate (PS). Due to the relative high adsorption capacity of CuFe2O4/MMT-k10, the adsorption feature was considered an enhancement of LVF degradation. In addition, the response surface methodology (RSM) model was established with the parameters of pH, temperature, PS dosage, and CuFe2O4/MMT-k10 dosage as the independent variables to obtain the optimal response for LVF degradation. In cycle experiments, we identified the good stability and reusability of CuFe2O4/MMT-k10. We proposed a potential mechanism of CuFe2O4/MMT-k10 activating PS through free radical quenching tests and XPS analysis. These results reveal that CuFe2O4/MMT-k10 nanocomposite could activate the persulfate, which is an efficient technique for LVF degradation in water.

scholarly journals Biosorption of lead ions by exopolysaccharide producing Azotobacter sp.

2021 ◽  
Vol 42 (1) ◽  
pp. 40-50
Author(s):  
P. Dhevagi ◽  
◽  
S. Priyatharshini ◽  
A. Ramya ◽  
M. Sudhakaran ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Response Surface ◽  
Functional Groups ◽  
Contact Time ◽  
Sewage Water ◽  
Energy Dispersive ◽  
X Ray ◽  
Scanning Electron

Aim: Removal of lead from wastewater using Azotobacter species and optimisation of various parameters to maximise the adsorption of lead by response surface methodology as a tool. Methodology: The bacterial isolate UBI-7 recovered from sewage water irrigated soil was examined for its biosorption potential towards lead. The lead removal efficiency of Azotobacter salinestris was studied with respect to metal concentration (50-250 mg l-1), contact time (24-120 hrs), and pH (4-8).Using response surface methodology, these factors were optimized and R2 value obtained was 0.9710 for lead ions, which indicates the validity of the model. Observation with Fourier Transform Infrared (FTIR), Scanning Electron Microscope imaging (SEM) and Energy Dispersive X-ray Spectroscopic analysis (EDX) were carried out to confirm lead biosorption by Azotobacter salinestris. Results: The lead tolerant bacterium isolated from sewage water irrigated soil (UBI-7) was recognized as Azotobacter salinestris by 16S rRNA based gene sequence analysis. The highest removal percentage of Pb (61.54) was 50 mg l-1 in 72 hrs equilibration period. Interaction effect between different levels of Pb and different contact time of the solution were found to be significant. Lead biosorption by the organism was confirmed by the changes in stretching intensities of functional groups as well as appearance of strong OH stretching at 3291.69 cm-1. Images obtained from Scanning Electron Microscope and Energy Dispersive X-ray Spectroscopic studies of the bacteria (UBI-7) before and after biosorption clearly indicated lead adsorption. Interpretation: Current study proves that the functional groups of Azotobacter salinestris are involved in lead biosorption from aqueous solution which was confirmed through FTIR.EDX analysis also elucidated the lead absorption by the bacterial cells. Hence, this could be effectively utilized for decontamination of lead from the polluted environment. Key words: Azotobacter salinestris, Biosorption, Lead, Response surface methodology

scholarly journals Modelling and optimization of zinc recovery from Enyigba sphalerite in a binary solution of hydrochloric acid and hydrogen peroxide

2020 ◽  
Vol 120 (11) ◽  
Author(s):  
I.A. Nnanwube ◽  
O.D. Onukwuli
Keyword(s):  
Genetic Algorithm ◽  
Hydrogen Peroxide ◽  
Response Surface Methodology ◽  
Hydrochloric Acid ◽  
Response Surface ◽  
Binary Solution ◽  
Infrared Analysis ◽  
Zinc Recovery ◽  
X Ray ◽  
Stirring Rate

SYNOPSIS This work focused on the prediction of optimal conditions for zinc recovery from sphalerite in a binary solution of hydrochloric acid and hydrogen peroxide. The sphalerite sample was characterized with X-ray fluorescence spectrometry (XRF), X-ray diffractometry, and Fourier transform infrared analysis (FTIR). The central composite design of response surface methodology (RSM) developed in Design Expert software and the genetic algorithm (GA) tool in matlab, were deployed for the optimization exercise. The leaching temperature, acid concentration, stirring rate, leaching time, and hydrogen peroxide concentration were defined as input variables, while zinc yield was the response. An ideal zinc yield of 90.89% could be obtained with a leaching temperature of 84.17°C, HCl concentration of 3.14 M, stirring rate of 453.08 r/min, leaching time of 107.55 minutes, and hydrogen peroxide concentration of 3.93 M using RSM; while a yield of 87.73% was obtained using GA. Analysis of the post-leaching residue revealed the presence of sulphur, zircon, fluorite, gahnite, anatase, and sylvite. Keywords: sphalerite leaching, genetic algorithm, optimization, response surface methodology.

scholarly journals Applying Response Surface Methodology to optimize the decarbonization process of Timahdit oil shale

2019 ◽  
Vol 8 (5) ◽  
pp. 372-379 ◽  
Author(s):  
Laila Makouki ◽  
Meriem Tarbaoui ◽  
Samia Glissi ◽  
Said Mansouri ◽  
Hassan Hannache ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Acetic Acid ◽  
Response Surface ◽  
Oil Shale ◽  
Processing Time ◽  
Texture Evolution ◽  
Optimal Conditions ◽  
X Ray ◽  
Decarbonization Process ◽  
Scanning Electron

The present article aims to optimize the decarbonization of Timahdit oil shale layer Y by removing carbonates from the raw rock using acetic acid. The response surface methodology “central composite design (CCD)” has been used as a method of optimization to study the 3 factors of the process. The factors studied are the concentration of the acid, the processing time, and the ratio (liquid/solid). The optimal conditions with 68.17% of residue rate are obtained with 2 mol/l as concentration, 120 min as a time of treatment and 10.02 for the ratio.The raw (Y) and optimized materials (YO) were characterized by Scanning Electron Microscopy (SEM), X-ray fluorescence (XRF) and X-ray diffraction (XRD). The results showed that the acetic acid used to remove carbonates affects the chemical composition and the texture evolution of the residues.

Tribological properties of glass/carbon hybrid composites through inter-ply arrangement using Response Surface Methodology

2018 ◽  
Vol 5 (9) ◽  
pp. 19828-19835
Author(s):  
Abhijeet Nayak ◽  
Dipak Kumar Jesthi ◽  
Bharat Chandra Routara ◽  
Diptikanta Das ◽  
Ramesh Kumar Nayak
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Tribological Properties ◽  
Hybrid Composites ◽  
Glass Carbon

Investigating the quality characteristics of Al5052/SiC metal matrix composites machined by CO2 laser curve cutting

2015 ◽  
Vol 232 (1) ◽  
pp. 3-19
Author(s):  
Vikas Sharma ◽  
Vinod Kumar
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Metal Matrix ◽  
Desirability Function ◽  
Cutting Speed ◽  
Optical Microscope ◽  
Quality Characteristics ◽  
X Ray ◽  
Sic Particles ◽  
Quality Aspects

This article explores the quality characteristics of laser curve cutting of metal matrix aluminium 5052 alloy reinforced with SiC particles. These alloys are extensively used in aerospace industries due to their unique mechanical properties. The response surface methodology has been used to design the mathematical models with respect to input and output characteristics parameters. The desirability function approach has been used to optimize the input parameters like cutting speed, laser power, stand-off distance, nozzle diameter, nitrogen gas pressure, percentage of reinforced SiC particles, arc radius by considering multiple-performance characteristics. The various quality aspects of machined specimens were analysed using optical microscope, scanning electron microscopy, X-ray diffraction and energy-dispersive X-ray analysis techniques. The response surface methodology predicted models were validated by performing various confirmatory experiments. The percentage of error for the dross height, kerf taper and kerf width was found to be 4.62%, 6.55% and 5.04 % which signifies that predicted model is adequate.

Qualitative Evaluation of Sister Chromatid Exchanges Elicited by Combinations of Genotoxic Compounds Using Response Surface Methodology

1988 ◽  
Vol 7 (7) ◽  
pp. 975-986
Author(s):  
Richard P. Solana ◽  
Walter H. Carter ◽  
John D. Wilson ◽  
Vernon M. Chinchilli ◽  
Richard A. Carchman
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Sister Chromatid ◽  
Sister Chromatid Exchanges ◽  
X Rays ◽  
Response Curves ◽  
Additive Interaction ◽  
Underlying Assumption ◽  
X Ray ◽  
Chromatid Exchanges

Response surface methodology (RSM), a collection of statistical and mathematical techniques, can empirically model multiple agent interactions. The use of RSM allows modeling of the interaction at all levels of each agent, rather than focusing on a single level of effect, thereby describing the changing interaction present. Further, this technique allows qualitative analysis of the resultant model of the combination exposure for existing interactions. RSM was used in the statistical analysis of sister chromatid exchanges (SCE) elicited by combination exposures of genotoxic agents, ethylnitrosourea (ENU) with cis-diaminedichloroplatinum (II) (DDP), and DDP with x-rays. ENU and DDP each exhibited curvilinear concentration-related increases in SCEs. X-ray exhibited a linear increase in SCEs. For the DDP-x-ray combination, RSM analysis indicates a less-than-additive interaction, suggested by the nonparallel concentration-response curves of one agent at varying concentrations of the other. For the DDP-ENU combination, an increasingly less-than-additive interaction was detected. This descriptive ability is shown to be useful in suggesting hypotheses about mechanisms of action. Employing a polynomial model assumes effect-addition as an underlying assumption of additivity. Models with other underlying assumptions of additivity also can be used.

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