•Comparative study of water-cooled cooler block arrangements led to optimized PVT-III layout using Response Surface Methodology (RSM).•Introduction of 0.3 wt% TiO2/nanofluid, notably enhancing ...electrical efficiency in PVT systems.•Positive correlation identified between rising nanofluid concentration and improved system performance.•Peak electrical efficiencies were attained under elevated solar irradiance and flow rates.
The current study presents a partitioned rectangular-shaped heat sink for improving the PVT system performance. The experiment was examined under various experimental parameters. Five cooler block types with different dimensions were arranged to share the same total contact area with the panel back surface. These cooler blocks were placed in different arrangements, namely (PVT-I, PVT-II, PVT-III, PVT-IV, PVT-V), and studied comparatively using water. The dimensions and numbers of each cooler block arrangement were altered, while maintaining the same surface area in contact with the photovoltaic panel. Through the response surface methodology (RSM) optimization, the optimal arrangement with the best performance was determined, and then TiO2/nanofluid was applied to that arrangement with different volumetric concentrations. Using water, the highest electrical and thermal efficiencies were obtained by case PVT-III with values of 19.39 % and 63.72 %, respectively. This was followed by PVT-II, PVT-V, PVT-I, and PVT-IV in that order for electrical efficiency; and at the same time by PVT-II, PVT-I, PVT-IV, and PVT-V in that order for thermal efficiency. The RSM method recommended the optimal arrangement case as case PVT-III. By using nanofluid in that case arrangement, the highest electrical efficiency value was recorded upon using 0.3 wt% and operating the system at 1.5 L/m and 900 W/m2. Regarding the thermal efficiency results, in that case, the highest and lowest values were recorded upon using 0.3 wt% and 0.1 wt%, respectively, with values of 72.49 % and 31.19 %. Increasing the volumetric concentrations positively reflected on the system's performance, resulting in high efficiencies being achieved. In addition, the highest electrical efficiencies were obtained at high levels of solar irradiance and flow rates.
Gellan is one of the most important industrial microbial exopolysaccharides used for a wide range of applications in food, pharmaceutical, and oil. In this study, a native strain of Sphingomonas ...producing gellan gum was identified from rice roots. Various factors, including carbon and nitrogen sources, pH levels, fermentation duration, and aeration, were investigated to enhance the production of gellan by Sphingomonas sp. SM2. The highest efficiency in gum production was achieved by a medium composed of 30 g/L glucose. When the carbon-to-nitrogen ratio was 30, organic nitrogen caused this increase. By incorporating all relevant factors, the optimized fermentation process can yield a gum concentration of 8.64 ± 0.34 g/L. The total carbohydrate content of the native gum was found to be 52.62 ± 0.52%. The existence of mucilage surrounding the bacterial cells was verified by scanning electron microscopy images. The extracted gellan gum was characterized using FTIR, 1H NMR, and HPLC analyses. The structure of the gum was confirmed by comparing it with the standard gellan gum. The production of gellan gum by Sphingomonas sp. SM2 using the utilization of diverse carbon sources suggests its immense potential as a gellan producer.
•A strain of Sphingomonas found naturally in rice roots has been determined as gellan producer.•The optimized fermentation process resulted in the production of 8.64 ± 0.34 g/L of gum.•FTIR, HPLC, and 1H NMR techniques confirmed the production of gellan gum.
There is always uncertainty in industrial manufacturing. These uncertainties have an undesirable impact on the products if deterministic optimization approaches are employed. In order to have ...products as desired, uncertainties must be quantified in the design process. This paper presents a robust design optimization of an outer rotor surface mounted permanent magnet motor with particular application in the hybrid vehicle using the design for six-sigma methodology. Due to very long computational time of robust optimization, a ten high-dimensional surrogate model of the system using the Box-Behnken response surface methodology (RSM) is integrated with the particle swarm optimization (PSO). This causes a significant improvement in the effectiveness and efficiency of optimization. The results acquired from RSM are verified by their simulation using the finite-element method, and the accuracy of RSM is proved. Finally, the deterministic and robust optimized motors are simulated in mass production using Monte Carlo analysis, and six-sigma quality achievements are demonstrated.
•Phenolics were extracted from MOLs using customised deep eutectic solvents (DES).•DES-based ultrasonic-assisted extraction (UAE) conditions were optimized by RSM.•DES-based UAE exhibited high ...efficiency for the extraction of the phenolic compounds.•DES-based UAE showed strong antioxidant activities.•Phenolic constituents in the MOLs extracts were analyzed.
In this study, an ultrasonic-assisted extraction (UAE) procedure with selected deep eutectic solvents (DES) as solvent was first designed to simultaneously optimize the total phenolic/flavonoid content (TPC/TFC) and antioxidant activities of Moringa oleifera L. leaves (MOLs) by using response surface methodology (RSM). The key factors for RSM were selected based on the design of the experimental results along with a three-factors-five-level, central composite design (CCD), including 20 experimental runs. The analysis of variance (ANOVA) results revealed that the water content in DES had a significant influence on all responses, while the ultrasonic time and the ratio of liquid to solid had no statistically significant effects on the total phenolic content. The optimal conditions of the combination of TPC/TFC and antioxidant activities were obtained as follows: 37% water content in DES, 144 W ultrasonic power, and 40 °C ultrasonic temperature. The measured parameters corresponded with the predicted results. Moreover, a comparative study confirmed that the optimized DES-based UAE yielded further higher TPC, TFC, and antioxidant activities than other extraction methods. The results of HPLC analysis in optimized conditions verified that the MOLs extracts with DES-based UAE included 14 phenolic compounds with high concentrations of vicenin-2 (17.6 mg/g) and orientin (23.6 mg/g). The present study supplied a green and high-efficient method for extracting high levels of anti-oxidative phenolic compounds from MOLs.
The purpose of this research was to achieve the best performance, combustion and emission characteristics of a marine engine fueled with hydrogen (5%, 10% and 15% energy fraction), water (2, 4 and ...6 wt%) and rapeseed methyl ester (RME) blend fuel by the multi-objective optimization. Based on the experimental results of the engine at 50%, 75% and 100% loads, the computational fluid dynamics (CFD) model was developed, and an improved chemical kinetic mechanism was developed to simulate the fuel combustion process. The response surface methodology (RSM) was used to optimize the combustion and emission characteristics of the marine diesel engine. The result showed that the hydrogen and water can improve the combustion and emission characteristics of the marine engine. The best solution was to select the desirable value of 0.632, and the engine achieves the best state by fueling R + 15H + 2.5W at 74.69% load. At the point, the optimum values of brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), nitrogen oxide (NOx), hydrocarbon (HC) and carbon monoxide (CO) emissions were 208.31 g/kW·h, 39.22%, 941.21 ppm, 325.86 ppm and 1073.4 ppm, respectively. For this study, adding appropriate hydrogen and water to biodiesel can achieve efficient, low carbon and clean combustion in marine engine.
•Effects of hydrogen/biodiesel/water blend fuels on combustion and emission characteristics are compared.•Optimum blend fuel is obtained for diesel engine.•An improved 3D model and chemical kinetics mechanism are developed.•The performance optimization was carried out by the response surface methodology.
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•Good activity of Fe(II)-NClin-CPE for indirect voltammetric determination of dichromate.•Strong effect of pH on the electrode response based on RSM experimental design ...results.•Decrease in oxidation peak current of Fe(II) by adding dichromate to the solution.
A novel, simple, cheap and very sensitive modified carbon paste electrode (CPE) was used for indirect determination of dichromate in aqueous solution. Peak current of Fe(II) redox system exited form Fe(II)-exchanged clinoptilolite nanoparticles modifier (Fe(II)-NClin) at the surface of CPE was decreased in the presence of dichromate. Hence, this decrease in peak current was used for indirect determination of dichromate. Raw and modified zeolite and CPE were characterized by XRD, FT-IR, SEM-EDX, BET, X-ray map, electrochemical impedance spectroscopy (EIS) and TEM techniques. EIS results confirm that the Fe(II)-NClin/CPE has the best charge transfer efficiency with respect to raw CPE and NClin/CPE. To study the effects of more influencing experimental variables (such as modifier% and loaded of Fe(II), solution pH and scan rate) and reducing numbers of experiments experimental design was applied by response surface methodology (RSM). Under optimum conditions, the current response of Fe(II)-NClin/CPE was inversely proportional to Cr2O72− in the concentration range from 2.0×10−9–4.0×10−3molL−1 with a DL of 1.1×10−11molL−1.
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•Potential of biodiesel production from fresh water macroalgae, Rhizoclonium sp. was investigated.•The oil was extracted using hexane solvent extraction method.•Oil extraction ...optimization process done by RSM.•This study signifies that the biodiesel produces from fresh water macroalgae.
Optimization of biodiesel production from freshwater macroalgae, Rhizoclonium sp. was investigated in this study. Biodiesel production process parameters such as chemical solvent extraction, hexane:ether and different extraction techniques were optimized by using the response surface methodology based on the central composite design. Optimization of the transesterification process was conducted by varying two factors each at three different levels and this required a total of thirteen runs. A quadratic model was created to predict the biodiesel yield where the R2 value was found to be 0.97, which indicates the satisfactory accuracy of the model. Based on the results, the optimum process parameters for transesterification of the macroalgae Rhizoclonium sp. oil mixture at an agitation speed of 300 rpm over a period of 180 min was found to be a hexane:ether molar ratio 1:1(40 mL), NaOH catalyst concentration of 1 wt% and reaction temperature of 45 °C. Finally, a process optimization found highest macroalgae oil by simple treatment was 0.376 ± 0.14 g and ultrasonic treatment was 6.044 ± 0.81 g is the highest of biodiesel weight. For transesterification reaction from macroalgae oil, a triglyceride was mixed with 0.25 g methanol converted to biodiesel into methyl esters. The biodiesel weight 0.174 ± 0.034 g and 82.2% of the total fatty acid methyl esters (FAME) were confirmed from gas chromatography (GC) analysis. The biodiesel properties were characterized and the results obtained. Design-Expert Version 11 was used to draw both 3D surface plots and 2D contour plots to predict the optimum biodiesel yield.
•The nanoliquid flow over a wedge is modeled using the modified buongiorno model.•The heat transfer rate is optimized using response surface methodology (RSM).•Sensitivity of the heat transfer rate ...towards pertinent parameters is evaluated.•Exponential and thermal-based heat sources are scrutinized in the model.•The thermo-migration and haphazard motion of nanoparticles is examined.
Sensitivity analysis of the heat transfer rate in the flow of the hybrid nanoliquid C2H6O2−H2O (base liquid) +MoS2−Ag (nanoparticles) over a wedge using the Response Surface Methodology (RSM) is carried out. The nanomaterial is modeled using the modified Buongiorno nanofluid model (MBNM) that considers the major slip mechanisms and the effective properties of the hybrid nanoliquid. Two distinct heat sources- linear thermal heat source and an exponential space-dependent heat source are taken into account. The governing nonlinear two-point boundary-layer flow problem is treated numerically. The effects of pertinent parameters on the flow fields in the boundary layer region are represented graphically with suitable physical interpretations. The exponential heat source and slip mechanisms are used to study the sensitivities of the heat transfer rate. Both heat source mechanisms lead to an improvement in the temperature profile, in which the effect of the exponential space-related heat source is predominant. The Brownian motion parameter was found to be the most sensitive to the heat transfer rate.
•UPLC-MS-MS for determination of veterinary residues.•Residues sulfadimidine, sulfaquinoxaline, diaveridine, vitamin K3 in poultry tissues.•Decline curve study according to MRL values.•Greenness ...assessed by analytical Eco-scale, AGREE coupled with AGREEprep.•Competence via EVG framework as Efficiency, validation, and greenness.
Antibacterial medications are receiving the most attention due to hypersensitivity reactions and the emergence of bacterial mutants resistant to antibiotics. Treating Animals with uncontrolled amounts of antibiotics will extend beyond their lives and affect humans. This study aims to determine the concentration of the residues of sulfadimidine, sulfaquinoxaline, diaveridine, and vitamin K3 in the tissues of poultry (muscles and liver) after treatment with the combined veterinary formulation. A UPLC-MS-MS method was developed using Poroshell 120 ECC18 and a mobile phase composed of acetonitrile and distilled water, containing 0.1 % formic acid, in the ratio of (85:15 v/v) at a flow rate of 0.6 mL/min. Sample extraction solvent was optimized using response surface methodology (RSM) to be acetonitrile: methanol in the ratio (49.8: 50.2 v/v), and the method was validated according to the FDA bioanalytical method validation protocol over the range (50–1000 µg/Kg) for sulfaquinoxaline and (50–750 µg/Kg) for the other 3 drugs. The greenness of the sample preparation and analytical method was assessed by applying Analytical Eco-scale (AES) and AGREE coupled with AGREEprep. The Competence of the study was evaluated via the EVG framework known as Efficiency, validation, and greenness, to achieve a balance point represented by a radar chart. The method was applied to decide the time required for poultry products to be safe for human use after administration of the studied drugs. It was found that, after the administration of the last dose, minimally 7 days are required till the levels of the drugs drop to the maximum residue limit determined by the FDA/WHO in animal tissues.
