Response Surface Methodology

Epoxidized natural rubber–alumina nanoparticle composites were prepared by melt compounding with an internal mixer for a constant filler loading of 10 phr. Mixer parameters such as the mixing temperature, mixing time, and rotor speed were screened and optimized with response surface methodology to maximize the impact strength. The parameters were selected as three independent variables and the impact strength (J/m) was selected as the response in a screening factor study. The mixing temperature and its interaction terms were identified as insignificant factors with a P value greater than 0.0500. The optimum calculated values of the tested variables (rotor speed and mixing time) for the maximum impact strength were found to be a rotor speed of 60 rpm and a mixing time of 6 min with a predicted impact strength of 208.88 J/m. These predicted optimum parameters were tested in real experiments. The final impact strength was found to be close to the predicted value of 215.84 J/m, with only a 3.33% deviation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

In this paper, the response surface methodology (RSM) and finite element method (FEM) have been used to develop predictive models for the simulation and optimization of heat transfer process. The input variables were the material conductivity as well as the radiation emissivity, length and width of the recesses. The response variable considered was the thermal transmittance. In order to minimize the thermal transmittance, the RSM technique and FEM analyses have been developed in combination and applied to optimize this parameter. A central composite design (CCD) as the standard design of the RSM technique was used to evaluate the effects and interactions of the six previous factors. Next, the optimal design obtained from the RSM analysis is exposed, demonstrating its ability to build a quadratic polynomial model and to solve nonlinear thermal problems. Finally, analysis of variance (ANOVA) has been used to check the significance of response surface polynomials and FEM models so that...

Chemical activation was used to prepare a low-cost activated carbon (AC) from an agricultural waste material: sugarcane bagasse. It was used as a green biosorbent for the removal of two cationic dyes from aqueous solutions (Methylene blue (MB) and Malachite Green (MG)). Central composite design (CCD) using response surface methodology (RSM) was applied in this work in order to run a limited number of experiments. The possibility of revealing the interaction of three selected factors: activation temperature, activation time, and chemical impregnation ratios at different levels for the process of preparing the AC were studied. Two-second order quadratic regression models for a yield of AC and capacity of adsorption were developed using JMP Software.The results of the process of optimization were carried out; it showed a good agreement between the predictive response of RSM model and the obtained experimental values with high correlation coefficients (R2) which indicates the efficacy o...

This paper presents an optimization of a lightweight biopolymer drilling fluid for underbalanced drilling (UBD) using Response Surface Methodology (RSM). Concentrations of four raw materials (glass bubbles, clay, xanthan gum and starch) were varied to analyze their effects on three vital responses: density, plastic viscosity (PV) and yield point (YE') of the fluid. Based on the results, the optimum condition was achieved at concentrations of glass bubbles, clay, xanthan gum and starch of 24.46% w/v,0.63% w/v, 0.21% w/v and 2.41% w/v, respectively. The results showed that it is possible to predict the three response parameters using models generated by RSM since the experimental values were found to be in good agreement with the predicted values (error <1.0, standard deviation < 0.5 and accuracy > 98.5%). (C) 2015 Elsevier B.V. All rights reserved.

Link to Full-Text Articles :
http://ac.els-cdn.com/S0920410515001138/1-s2.0-S0920410515001138-main.pdf?_tid=1b1b3aee-4010-11e5-b09d-00000aab0f01&acdnat=1439287542_9fd31980444c45c5e189eeb04e68221c

Submerged Arc Welding (SAW) is a common arc welding process which is used to join thick and heavy sections. The basic characteristics of this process are high deposition rate, ability to weld thick sections with ease and longer weld runs. The study of weld bead geometry is important, as it determine the stress carrying capacity of a weld. For the same reason, this paper highlights the analysis and study of process parameters: arc Voltage, welding current, travel speed and electrode extension, on the bead geometry response such as, bead height, bead width and bead penetration. Design Expert 8.0 with 4 factors, 5 levels, rotatable Central Composite Design. was used to develop relationship for predicting weld bead geometry, which enables to quantify the direct and interaction effects. Mathematical models prepared for the submerged arc welding of 16mm thick mild steel by using response surface methodology which co relate the process variables with the bead geometry characteristics then ...

Wastewater reuse has been attracted a lot of attention in recent years especially in places with low water availability. The effluents that were considered to be discharged are now could be used as potential sources of reusable water. In this study, variables affecting the removal of ethylene glycol (EG) by adsorption on granular activated carbon (GAC) from the synthetic wastewater solutions were optimized by response surface methodology (RSM) using a central composite design. The investigated factors were temperature, EG concentration, contact time, activated carbon amount and granular size. Adsorption kinetic was also studied and an acceptable correlation between Langmuir model and experimental data was observed. As a result, a modified third degree equation was proposed and used to find the optimized condition. The maximum adsorption was achieved at 27.7 oC with 0.8 g of 20-30 mesh activated carbons for an EG feed concentration of 135 mg/L at 210 minutes.

This paper presents a study for the development of first- and second-order tool-life models at 95% confidence level for turning high strength steel. The tool-life models are developed in terms of cutting speed, feed rate, and depth of cut, using response surface methodology and design of experiment. The effects of the main cutting variables (cutting speed, feed, and depth of cut) on tool life have been investigated by the application of the factorial design method. All of the cutting tests were performed using uncoated carbide tools under dry conditions. Tool-life contours have been generated from these model equations and are shown in different plots. Dual-response contours of metal removal rate and tool life are shown also. The results are presented in terms of mean values and confidence levels. © 1998 Elsevier Science S.A. All rights reserved.

http://ac.els-cdn.com/S0924013697004354/1-s2.0-S0924013697004354-main.pdf?_tid=7ea8c4dc-1d34-11e4-b1a5-00000aab0f6c&acdnat=1407307382_b0d7d5d96bfabc738bde8c6860d2acd2 
http://www.sciencedirect.com/science/article/pii/S0924013697004354

In this paper, second order rotatable designs of second type using symmetrical unequal block arrangements with two
unequal block sizes is suggested. This design is compared with second order rotatable designs of first type using symmetrical
unequal block arrangements with two unequal block sizes (Raghavarao, 1963) on the basis of efficiency

Bulk characteristics and deposition of gold nanoparticles on mica modified by (PAH) was studied byUV–visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM),dynamic light scattering (DLS) and atomic force microscopy (AFM). The size of gold nanoparticles (AuNPs)was 15 nm as determined by TEM and AFM. The electrophoretic mobilities and electrokinetic chargeof particles were quantitatively evaluated for a broad range of pH and ionic strength. Using Henry’smodel, it was calculated that the zeta potential of particles varied between − 50 mV and − 80 mV forpH 2 and pH 11, respectively (at 10−2M of NaCl). Measurements of nanoparticle deposition kineticswere performed under diffusion-controlled transport conditions using AFM and SEM imaging of particlemonolayers. The influence of the bulk suspension concentration was systematically studied. Additionally,the maximum coverage of particle monolayers, which monotonically increased with ionic strength, wasdetermined by SEM. The obtained data were in agreement with theoretical predictions derived from therandom sequential adsorption (RSA) model. It was also confirmed that by varying the bulk suspensionconcentration and ionic strength one can prepare homogeneous gold particle monolayers of controlledcoverage.

Optimal conditions for microwave-assisted extraction (MAE) of total phenols (TP), epicatechin gallate and antioxidant activity from prune (Prunus domestica), rejected in transformation process of plum to prune, were determined by response surface methodology. The central composite design was used to study the effects of three independent variables: microwave power, irradiation time and solvent polarity on the TP, epicatechin gallate and antioxidant activity. Epicatechin gallate was identified as a major phenolic compound in prune extract by RP-HPLC. Microwave power and irradiation time significantly affected all responses (P < 0.01). The highest TP (598.89 mg GAE/100 g prune) was obtained using water as an extraction solvent at 500 W, during 115 s. However, the optimal conditions for epicatechin gallate extraction were ethanol 80%, 435 W and 120 s. MAE is more efficient than conventional extraction method to obtain TP from prune. The experimental values were reasonably close to the predicted values confirming the validity of the predicted models.

Background: Blended biomass, a new feedstock for pellets production potentially be viable to support the demand for wood pellets at present and in the future. Combustion behavior and characteristics tests were carried out in thermogravimetry (TG) analyzer with an air flow rate of 100 ml/min and heating rate of 20 °C/min. Heat flow and heat required for the biomass reaction was measured using differential scanning calorimeter (DSC). Objective: The purpose of this study was to investigate the combustion behaviour and thermal properties of both individual and blend agricultural (reed canary grass, timothy hay and switchgrass) and forestry biomass (spruce and pine). Results: The TG results showed that the combustion behavior of all the biomass samples including the blends were almost similar. Two main stages of combustion reaction were presented by differential thermal analysis (DTA) curve. The heat released from the blended biomass (6.94 – 9.26 kJ/kg) was higher than the individual agricultural biomass (4.59 – 6.78 kJ/kg) but lower than individual spruce (10.2kJ/kg) and pine (11.13kJ/kg). Conclusion: The findings indicate that the reactivity of the individual agricultural biomass material changed due to blending. Overall, blending can help to increase the energy capacity and can improve the combustion characteristics.

The objective of this work was to study the effect of initial pH and carbon and nitrogen content, supplied as glucose and malt extract (ME) respectively, on the production and composition of exopolysaccharides (EPS) produced by the medicinal fungus Ganoderma lucidum (Curtis) P. Karst in submerged culture. The experiment was carried out in flasks with 100 mL of the medium during 15 days at 28 ºC in an orbital shaker at 150 rev min-1. A central composite design with a minimal number of 20 runs was used [1]. All three studied factor were found to influence significantly the EPS production (and mycelial biomass). The maximum EPS production (594.3 mg L-1) was obtained for initial pH of 5.84 and initial contents of 33.6 and 4.48 g L-1 of glucose and ME respectively. Higher initial pH (6.68), glucose (40.95 g L-1) and ME (5.58 g L) contents on the culture medium lead to an increase of mycelial biomass but to a decrease in EPS, and consequently to a decrease in the production efficiency. Th...

The Response Surface Methodology (RSM) is used here to analyse a large set of experimental data regarding the mechanical and environmental performances of an internal combustion engine (ICE) used to power a farm tractor. The aim is twofold: (i) to demonstrate the effectiveness of RSM in quantitatively assessing the effects of biofuels on a complex system like an ICE; (ii) to supply the users with easy-to-use models to predict the effect of biofuel blends on performance and emissions of tractor engines and find an optimal blend according to given user-defined parameters. The methodology showed good prediction abilities: the calculated average errors for the first models were lower than 0.38 and 1.40% on 6 test cases, with a higher accuracy in the assessment of the ICE mechanical performance. As a result, two effective and user-friendly models for torque and NOx emissions were developed; they were subsequently used to single out some fuel blends having interesting effects in terms of ...