Response Surface Methodology-central Composite Design Research Articles

Sensitivity analysis of MHD nanofluid flow in a composite permeable square enclosure with the corrugated wall using Response surface methodology-central composite design

This work aims to conduct a numerical study on the magnetohydrodynamic (MHD) natural convection of nanofluid within a porous cavity corrugated hot and cold walls. The system comprises an external magnetic field. The study employs a finite element approach to solve the governing equations for momentum and energy conservation, while systematically varying influential parameters such as the Rayleigh number (Ra), Hartmann number (Ha), Darcy number (Da), and the magnetic parameter (M). The fluctuations in these parameters allow for the analysis of their effects on the Nusselt number, flow patterns and thermal performance. A notable innovation of this research lies in the incorporation of a Response Surface Methodology (RSM)-based sensitivity analysis. This approach yields valuable insights for optimizing thermal management and enhancing energy efficiency in advanced Magnetohydrodynamics (MHD) systems. According to conclusive data, employing a permeable partition instead of a solid partition leads to a notable enhancement in the mean Nusselt value. Specifically, at Ra = 100, the improvement is recorded at 26.28%. Furthermore, at Ra = 104, this enhancement reaches its peak, with a substantial increase of 56.5%.

Thermo‐mechanical properties and optimization of sodium alginate as a polymer backbone substrate for biosensor application

AbstractThis study was aim to optimize the formulation of the sodium alginate biosensor substrate with incorporation of sodium alginate (1%‐6%(w/v)) as a polymer backbone and glycerol (10–50 wt%) as a plasticizer. The effect of their interaction on film's tensile strength (TS) and elongation at break (EB) were analyzed via response surface methodology‐central composite design (RSM‐CCD). The optimum parameter of the films for the maximum TS was at 1.90%(w/v) of sodium alginate and 17 wt% of glycerol and for maximum EB was at 4.89%(w/v) of sodium alginate and 49.65 wt% of glycerol. The optimum parameter of the films had revealed the better TS was at lower sodium alginate content and better EB was at higher glycerol content. In terms of thermal stability, the thermal decomposition temperature (Tonset) of sodium alginate decreased with the incorporation of glycerol.

Photocatalytic degradation of tetracycline using a novel WO3–ZnO/AC under visible light irradiation: Optimization of effective factors by RSM-CCD

Mitigating pharmaceutical pollution in the global environment is imperative, and tetracycline (TC) is a commonly utilized antibiotic in human and veterinary medicine. The persistent existence of TC highlights the necessity of establishing efficient measures to protect water systems and the environment from detrimental contaminants. Herein, a novel rhubarb seed waste-derived activated carbon-supported photocatalyst (WO3–ZnO/RUAC) was synthesized by combining wet impregnation and ultrasonic methods. The activated carbon (AC) was obtained from rhubarb seed waste for the first time via chemical activation. The function of AC as an electron acceptor and in separating electron-hole pairs was illuminated by characterization analyses that included XRD, FTIR, XPS, SEM, TEM, PL, EIS, TPC, and UV-DRS. Using the response surface methodology-central composite design (RSM-CCD) technique, the synthesis parameters of the composite were systematically optimized. Under ideal conditions, with a TC concentration of 33 mg. L−1, pH of 4.57, irradiation time of 108 min, and catalyst dose of 0.85 g. L−1, the highest degradation efficiency of TC by this composite, achieved 96.5%, and it was reusable for five cycles. Subsequently, trapping tests and electron spin resonance (ESR) analysis were conducted, elucidating that •OH and •O2− radicals played pivotal roles in the photocatalytic degradation of TC. This research offers valuable insights into utilizing the AC-based photocatalyst to degrade pharmaceutical micropollutants effectively.

Synthesis of Cu3Fe4V6O24 Nanoparticles to Produce 1,2,3-Triazoles by Azide-Alkyne Cycloaddition Reactions.

This paper presents the fabrication of novel Cu3Fe4V6O24 nanoparticles (NPs) via a facile sol-gel method as efficient nanocatalysts (NCs) to produce azide-alkyne 1,3-dipolar cycloaddition compounds. The effect of the calcination time on the formation of NPs was investigated. The as-prepared NPs were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), electron-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET) analyses. Cu3Fe4V6O24 NCs were applied to azide-alkyne 1,3-dipolar cycloaddition reactions. The effect of the catalyst loading, temperature, and time of reaction was optimized to improve the efficiency of the NC function by the response surface methodology-central composite design (RSM-CCD) method. In optimal conditions, the yield of the reaction was 96%. In addition, the effect of different solvents on the yield of the reaction was investigated. Moreover, Cu3Fe4V6O24 NPs efficiently catalyze different 1,2,3-triazoles in excellent yields.

Response Surface Methodology—Central Composite Design Optimization Sugarcane Bagasse Activated Carbon under Varying Microwave-Assisted Pyrolysis Conditions

Sugarcane bagasse (SB) is a widely available agro-industrial waste residue in China that has the potential to be converted into a cost-effective and renewable adsorbent. In this study, activated carbon (AC) was prepared from SB by microwave vacuum pyrolysis using H3PO4 as the activator. To enhance the sorption selectivity and yield, the pyrolysis process of SB-activated carbon (SBAC) should be well-designed. Central composite design was employed as an optimized experiment design, and response surface methodology was used to optimize the process parameters for maximized SBAC yield and its iodine number. The results showed that the optimized parameters obtained for the SBAC are 2.47 for the impregnation ratio (IR), 479.07 W for microwave power (MP), 23.86 mm for biomass bed depth, and 12.96 min for irradiation time, with responses of 868.7 mg/g iodine number and 43.88% yield. The anticipated outcomes were substantiated, revealing a marginal 5.4% variance in yield and a mere 1.9% discrepancy in iodine number from the forecasted values. The synthesized adsorbents underwent comprehensive characterization through instrumental methodologies, including FT-IR, BET, and SEM. The SBAC produced by the pyrolysis method contained a regular and homogeneous porous structure with a specific surface area of up to 1697.37 m2/g and a total 1.20 cm 3/g volume, which has favorable adsorption of toxic and harmful substances in the environment.

Optimization and chemical free fabrication of green synthesized iron nanoparticles as potential MRI contrast agent.

The current research article has investigated the synthesis and characterization of novel iron nanoparticles (INPs) from neem and betel leaves extract combination using response surface methodology-central composite design and coated with chitosan-curcumin (CCINPs) as a biocompatible and contrast agent for magnetic resonance imaging (MRI). The coating of INPs with chitosan and curcumin (CCINPs) was carried out using a simple, easy, chemical-free ultrasonication method and characteristics were confirmed by UV-visible (Vis) spectrophotometer (UV-Vis), Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscope, atomic force microscopy, and vibrating sample magnetometer. The biocompatibility of the particles was ensured by conducting hemolytic and cell viability assays. The nanoparticle was found to be nonhemolytic (<5%) up to 150μg/mL for both INPs and CCINPs. The cell viability was stable (peripheral blood mononuclear cells-PBMCs) till 48h at 150μg/mL of INPs and CCINPs. Both the test results produced were found to be biocompatible and additionally, an in vitro MRI study of INPs and CCINPs demonstrated the efficiency of the nanoparticle as a negative contrast agent with enhanced contrast nature in CCINPs. Thus, overall results indicate that the green synthesized chemical-free novel CCINPs could be a potential candidate for a wide range of applications such as MRI, drug delivery, and in magnetic fluid hyperthermia.

Optimization of Heat Transfer Performance Using Response Surface Methodology-Central Composite Design (RSM-CCD) for Nano-Coolant (Al2O3+EG/W) in Electric Vehicle Battery

The presence of electric vehicles (EVs) must be supported by batteries that have good-quality energy storage. Battery power is critical to the development of electric cars. Temperature affects battery strength, so operating within the optimum temperature range must be ensured. During the charge and discharge processes, the electrochemical reaction generates hot energy, causing an increase in battery temperature. In this research, the solution to the problem is to make a cooling system with a mini channel cold plate and Al2O3 1%vol+EG/W (50:50) nano coolant. Optimization of heat transfer enhancement using Response Surface Methodology-Central Composite Design (RSM-CCD) and experimental tests with various flow rate variations. The research findings revealed that the RSM-CCD results and the outcomes of studies employing test equipment agreed that the highest cooling fluid flow rate was the most optimal condition, the highest T2 temperature drop of 17.63% occurred at a flow rate of 1.7 LPM, and the lowest T2 temperature was 13.13% at a flow rate of 1 LPM.

Kaolin–Polyvinyl Alcohol–Potato Starch Composite Films for Environmentally Friendly Packaging: Optimization and Characterization

This research paper introduces an innovative methodology to produce biodegradable composite films by combining kaolin, polyvinyl alcohol (PVA), and potato starch (PS) using a solvent casting technique. The novelty of this study resides in the identification and implementation of optimal synthesis conditions, which were achieved by utilizing the Response Surface Methodology—Central Composite Design. The study defines starch, polyvinyl alcohol (PVA), and kaolin as independent variables and examines their influence on important mechanical qualities, water absorption capacity, moisture content, and degradability as primary outcomes. The study establishes the ideal parameters as 5.5 weight percent Kaolin, 2.5 g of starch, and 3.5 g of PVA. These settings yield notable outcomes, including a tensile strength of 26.5 MPa, an elongation at break of 96%, a water absorption capacity of 21%, a moisture content of 3%, and a remarkable degradability of 48%. The study emphasizes that the augmentation of kaolin content has a substantial impact on many properties, including degradability, tensile strength, and elongation at break. Simultaneously, it leads to a reduction in the water absorption capacity and moisture content. The study’s novelty is reinforced by conducting an additional examination on the ideal composite film, which includes investigations using FTIR, TGA, and SEM-EDX techniques. The consistency between the predicted and experimental results is noteworthy, as it provides further validation for the prediction accuracy of Design Expert software’s quadratic equations. These equations effectively capture the complex interactions that exist between process parameters and selected responses. This study presents novel opportunities for the extensive utilization of PVA/PS composite films, including kaolin in various packaging scenarios, thereby significantly advancing sustainable packaging alternatives. The statistical analysis provides strong evidence supporting the relevance of the models, hence increasing our level of trust in the software’s prediction skills. This conclusion is based on a 95% confidence level and p-values that are below a threshold of 0.05.

Optimization of Protease Activity by Bacillus haynesii BK1H Using Response Surface Methodology

Proteases are enzymes that catalyze the hydrolysis of peptide bonds into oligopeptides and amino acids. Previous bacterial studies reported that eight proteolytic isolates had been isolated from Bledug Kuwu mud, Central Java. One of these isolates is BK1H which has a proteolytic index of 2.960 making it possible to be studied further. In this study, optimization of the protease activity of BK1H was carried out using 3 factors namely temperature, pH, and divalent metal cations. This research was conducted through several stages, (1) Bacterial culture regeneration, (2) Protease fermentation using the SmF method, (3) Determination of the type of protease, (4) One Factor at a Time (OFAT), (5) Plackett-Burman Design (PBD), (6) Response Surface Methodology-Central Composite Design (RSM-CCD), and (7) Confirmation of RSM-CCD optimization results on experimental results. OFAT experiment results showed the lowest activity and the highest activity was obtained at 37°C and 57°C; pH 6 and 8; and CaCl2 0.5 and 1.0 mM. The significance test of the 2 factors namely temperature and pH has a p value &lt;0.05, which indicates that these factors have a significant effect on protease activity. The optimum factor value in the RSM-CCD has a temperature of 63.10°C and pH 10.82, with the predicted activity of 149.910 U/mL, while the experimental results have activity of 157.630 ± 16.240 U/mL.

Microwave-assisted upcycling of plastic waste to high-performance carbon anode for lithium-ion batteries

The increasing demand for high-performance lithium-ion batteries (LIBs) has emphasized the need for affordable and sustainable materials, prompting the exploration of waste upcycling to address global sustainability challenges. In this study, we efficiently converted polypropylene (PP) plastic waste from used centrifuge tubes into activated polypropylene carbon (APC) using microwave-assisted pyrolysis. The synthesis of APC was optimized using response surface methodology/central composite design (RSM/CCD). Based on the RSM results, the optimal conditions for PP plastic conversion into carbon were determined as follows: HNO3 concentration of 3.5 M, microwave temperature of 230 °C, and holding time of 25 min. Under these conditions, the obtained intensity ratio of Id/Ig in PP carbon was 0.681 ± 0.013, with an error of 6.81 ± 0.013 % between predicted and actual values. The physicochemical studies, including FESEM-EDX, XRD, and Raman spectroscopy, confirmed the successful synthesis of APC samples. The APC 800 material exhibited a well-organized three-dimensional structure characterized by large pores and mesopores, enabling fast ion transport in the electrode. As a result, the APC 800 electrode demonstrated an initial discharge capacity of 381.0 mAh/g, an improved initial coulombic efficiency of 85.1%, and excellent cycling stability after 100 cycles. Notably, the APC 800 electrode displayed remarkable rate performance, showing a reversible capacity of 355.1 mAh/g when the current density was reset to 0.2 A/g, highlighting its high electrochemical reversibility. The outstanding characteristics of APC 800 as an anode electrode material for high-performance lithium-ion batteries suggest a promising future for its application in the field.

Biofuel production by Candida tropicalis from orange peels waste using response surface methodology

Citrus fruits are widely consumed worldwide due to their nutritional and health benefits. However, the disposal of citrus waste poses significant environmental challenges. Orange peels (OP) are a substantial by-product of fruit processing and hold great potential as a source for bioethanol production, promoting investment in utilizing agricultural waste for biofuel purposes. OP offers a cost-effective substrate for producing value-added compounds, including bioethanol. Autoclaved-water treated OP biomass exhibited the highest release of reducing sugars (68.2%) this results supported by SEM images of that Autoclaving has definite effect on the structure of the OP particles. Among the five tested microbes, Candida tropicalis was selected as a promising bioethanol candidate due to its ethanol tolerance and ability to utilize xylose. Preliminary screening using Plackett-Burman Design (PBD) was conducted to identify six influential factors affecting the fermentation process at three levels, determining the optimum response region for bioethanol production by C. tropicalis. The significant variables were further investigated using Response Surface Methodology-Central Composite Rotatable Design (RSM-CCRD) at five levels, a novel approach in this study. The addition of cysteine and resazurin as reducing agents increased bioethanol production by 2.9 and 2.1 times, respectively, from the treated OP. Under the optimized conditions obtained from RSM-CCRD, bioethanol production reached 16.7 mg/mL per mg/ml reducing sugars. Implementing all the optimized conditions, including an initial pH of 5.75, 3% yeast extract, 2.25 g/L cysteine, 4% inoculum size, 0.6 g/L ZnSO4, 0.29 g/L MgSO4, 0.3 g/L MnSO4, and substrate treatment with active charcoal before fermentation, the bioethanol yield increased by 2.2 times after three days of fermentation using co-cultures of C. tropicalis and Kluyveromyces marxianus. The fermentation process was conducted at 30 °C and 150 rpm. Exploring OP as a low-cost renewable substrate and employing efficient microorganisms open new avenues for bioethanol production.

Efficiency of FeSO4.7H2O as a Coagulant on Chromium Hexavalent Removal Using Coagulation-Flocculation Process: Optimization Using Response Surface Methodology

Response Surface Methodology-Central Composite Design (RSM-CCD) is widely employed in the process of optimizing the applications of coagulants for wastewater treatment. The experiment aims to evaluate the effect of the FeSO4.7H2O concentration and settling time on removing the chromium hexavalent (Cr (VI)) from wastewater by coagulation-flocculation using RSM-CCD. This experiment was carried out based on the results of the model and optimization using the RSM-CCD to obtain the removal efficiency of Cr (VI) as well as determine the influence of the concentration of FeSO4.7H2O (X1) and settling time (X2). The RSM-CCD experimental design uses a two-factor and two-level design with 13 experimental runs and 5 center points. Inter-variable regression coefficients are also produced with the elimination of Cr (VI). The ANOVA test results showed a fairly significant figure for the assembled model. The model validation results show that the proposed model is compatible with the experimental results. RSM optimization shows optimum conditions based on experimental FeSO4.7H2O coagulant concentration variables and coagulation time at 150 mg/L coagulant concentration and 60 minutes of time, and the prediction results based on RSM-CCD optimization using Design Expert show the most optimum condition at 165,562 mg/L coagulant concentrations and 60,527 minutes of time.

Developing a robust treatment of antibiotics removal using Bi2O3/Cdots synthesized via microwave-assisted precipitation optimized by central composite design

This study aims to optimize the development process of bismuth oxide/carbon dots (Bi2O3/Cdots) using microwave-assisted precipitation for antibiotics removal. Experimental design and analysis of optimum formulation predictions is conducted using the response surface methodology-central composite design (RSM-CCD). Analysis of variance (ANOVA) is used for model development and the fit optimized model is validated through actual experiments considering error estimation metrics. Optimal synthesis conditions is achieved by developing Bi2O3/Cdots 13.31%wt under 780 W microwaves for 17.35 minutes. The analysis of optical properties and crystallinity shows that the composite has a narrow bandgap compared to Bi2O3 with a lattice spacing of 0.32 nm. The morphological and topographical profiles shows that the composite structure consists of Bi2O3 rods with wavy, irregular, and rough surfaces decorated with colonies of Cdots. The chemical state of the composite consists of Bi, O, and C which are distributed throughout the surface with a lower binding energy compared to Bi2O3. Through disc diffusion, composite reduced the inhibition zone, which means it is able to reduce the antibacterial activity and antibiotic efficacy. The optimized composite is able to degrade 76.6% ciprofloxacin (CIP), 73.3% cefadroxil (CEF), 54.4% amoxicillin (AMX), and 60.3% mixed antibiotics (MIX). Our findings indicated that the developed Bi2O3/Cdots is capable of robust removal in various antibiotic pollutants.

Synthesis of graphene/Fe3O4/polyaniline nanocomposite for simultaneous removal of a binary mixture of malachite green cationic dye and acid red 1 anionic dye from aqueous solutions

This work demonstrates the effective removal of the binary combination of Malachite Green (MG) and Acid Red 1 (AR1) dyes using a graphene/Fe3O4/polyaniline (Gr/Fe3O4/PANI) nanocomposite. Various methods, such as FTIR, XRD, SEM, TEM, VSM, and UV–Vis, were employed to investigate the morphological and structural characteristics of the adsorbent. The response surface methodology-central composite design was used to assess the influence of parameters including solution pH, contact time, concentration of each dye, and adsorbent mass. The pH = 6.5, concentration for each dye of 16 mg L−1, adsorbent mass 30 mg, and contact time of 24 min were shown to be optimal for MG and AR1 dye adsorption. The isotherm models indicate that the dye removal process follows the Langmuir, and the adsorption capacity of the synthesized adsorbent for MG and AR1 was 196.10 and 150.27 mg g−1, respectively. The analysis of the collected kinetic models revealed that the quasi-quadratic kinetic model best fits the experimental results. Also, the thermodynamic values obtained from the data showed that the elimination process is endothermic and spontaneous. Finally, due to the high adsorption capacity of the synthesized adsorbent, the adsorbent recovery capability in 5 consecutive cycles for mixing both dyes was investigated.

Response Surface Methodology (RSM) Optimization of Pulsed Electric Field (PEF) Pasteurization Process of Milk-Date Beverage

Milk beverage with added natural sweetener is well appreciated by consumers as a nutritious and healthy product with unique sensorial quality attributes. However, this product requires a suitable pasteurization method without significant impact on the sensorial and physicochemical quality characteristics of the product. This study optimizes the pulsed electric filed (PEF) conditions for the pasteurization of a milk-date beverage with conserved physicochemical quality properties. The effect of process variables, such as pulse off time (20, 30, and 40 μs), number of pulses (20, 50, and 80), powder ratio (10, 15, 20, and 25% w/w), storage time (2, 4, and 6 days), and storage temperature (5, 15, and 25 °C) on the responses of total viable count (TVC), color difference (∆E), pH, and total soluble solids (TSS) was evaluated using the RSM central composite design (CCD). Pulse off time, number of pulses, date powder/milk ratio (w/w), storage time, and storage temperature greatly impacted the microbial and physical properties of the beverage. The optimal conditions for decreasing the microbiological load and physical change of beverages were a pulse off time of 40 μs, number of pulses of 80, and storage temperature of 5 °C for all powder ratios. These variables gave a safe beverage for up to six days. At optimal conditions, the values of pH, TSS, ∆E, and TVC were 7.51, 15.44 °Brix, 18.01, and 0.138 Log 10 CFU/mL, respectively, for the powder ratio of 10% (w/w); 7.66, 18.6 °Brix, 21.46, and 0.284 Log 10 CFU/mL, respectively, for the powder ratio of 15% (w/w); 7.56, 21.52 °Brix, 25.24, and 0.577 Log 10 CFU/mL, respectively, for the powder ratio of 20% (w/w); and 7.2, 24.2 °Brix, 29.34, and 0.741 Log 10 CFU/mL, respectively, for the powder ratio of 25% (w/w).

Development of high-performance MXene/nickel cobalt phosphate nanocomposite for electrochromic energy storage system using response surface methodology

Integrating electrochromism and energy storage capabilities of materials into a supercapacitor has great potential for developing intelligent and sustainable power systems and electronics. An intriguing aspect of such materials is their ability to undergo a real-time color change, indicative of the supercapacitor's charge level. In this work, Ti3C2 MXene/nickel cobalt phosphate (MXene/NiCoP) nanocomposite was successfully prepared by electrodeposition followed by spin-coating. The MXene/NiCoP nanocomposite was optimized using response surface methodology/central composite design (RSM/CCD). The proposed quadratic model displayed a residual standard error (RSE) of <5 %, indicating good model predictability. The conformational investigations, which included FTIR, Raman, XRD, XPS, FESEM, mapping, and EDX show that MXene/NiCoP nanocomposite was successfully synthesized. The synergistic effect offered by MXene/NiCoP nanocomposite resulted in superior and remarkable electrochromic energy storage performances in terms of coloration efficiency (56 cm2/C), optical contrast retention (84.45 %), specific capacity (453 mAh/g) and cycling stability (94.12 % after 5000 cycles). The MXene/NiCoP nanocomposite has exhibited exceptional electrochromic and supercapacitive properties, making it a promising candidate for advanced electroactive materials in future intelligent hybrid energy storage systems.

Adsorptive removal of acid red 18 dye from aqueous solution using hexadecyl-trimethyl ammonium chloride modified nano-pumice

Discharging untreated dye-containing wastewater gives rise to environmental pollution. The present study investigated the removal efficiency and adsorption mechanism of Acid Red 18 (AR18) utilizing hexadecyl-trimethyl ammonium chloride (HDTMA.Cl) modified Nano-pumice (HMNP), which is a novel adsorbent for AR18 removal. The HDTMA.Cl is characterized by XRD, XRF, FESEM, TEM, BET and FTIR analysis. pH, contact time, initial concentration of dye and adsorbent dose were the four different parameters for investigating their effects on the adsorption process. Response surface methodology-central composite design was used to model and improve the study to reduce expenses and the number of experiments. According to the findings, at the ideal conditions (pH = 4.5, sorbent dosage = 2.375 g/l, AR18 concentration = 25 mg/l, and contact time = 70 min), the maximum removal effectiveness was 99%. The Langmuir (R2 = 0.996) and pseudo-second-order (R2 = 0.999) models were obeyed by the adsorption isotherm and kinetic, respectively. The nature of HMNP was discovered to be spontaneous, and thermodynamic investigations revealed that the AR18 adsorption process is endothermic. By tracking the adsorption capacity of the adsorbent for five cycles under ideal conditions, the reusability of HMNP was examined, which showed a reduction in HMNP's adsorption effectiveness from 99 to 85% after five consecutive recycles.

Optimization of Azadirachta indica leaf extract mediated cerium oxide nanoparticles synthesis, characterization, and its applications

The present study focuses on the novel synthesis of cerium oxide (CeO2) nanoparticles from cerium nitrate hexahydrate by using Azadirachta indica (neem) leaf extract. The parameters associated with the green synthesis process were optimized utilizing the response surface methodology (RSM) paired with the genetic algorithm (GA) to produce a higher yield rate. The experiment run order for the CeO2 green synthesis is then generated using the central composite design in RSM. The regression equation was used as an optimization function, and the optimal values were identified through GA. Using optimized input process parameters, 0.3 g/10 mL of precursor concentration and 5 mL of Azadirachta indica leaf extract centrifuged for 20 min in the green synthesis process resulted in a maximum yield of 15.49 % CeO2 nanoparticles. The synthesized CeO2 nanoparticles are characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), particle size distribution, and zeta potential analyses, which are used to ensure their presence in the green synthesis process. Subsequently, the green synthesized CeO2 nanoparticles are dosed as an additive to the cotton seed biodiesel (CSB) at different proportions of 25, 50, and 75 ppm, respectively. The prepared biofuel's physico-chemical properties were measured as per ASTM standards and are closer to the diesel fuel. As a result, it was noted that optimizing the green synthesis process parameters gives a maximum rate of CeO2 yield. It is possible to efficiently use the CSB with CeO2 nanoparticles as a suitable replacement for diesel fuel.

Promoting Magnusiomyces spicifer AW2 Cell-Bound Lipase Production by Co-culturing with Staphylococcus hominis AUP19 and Its Application in Solvent-Free Biodiesel Synthesis.

Yeast-bacterium interaction has recently been investigated to benefit the production of cell-bound lipases (CBLs). Staphylococcus hominis AUP19 supported the growth of Magnusiomyces spicifer AW2 in a palm oil mill effluent (POME) medium to produce CBLs through a bioremediation approach, including oil and grease (O&G) and chemical oxygen demand (COD) removals. This research used the yeast-bacterium co-culture to optimize CBLs and cell biomass (CBM) productions through bioremediation using the statistical Plackett-Burman design and response surface methodology-central composite design. The CBLs were finally applied in biodiesel synthesis. The CBM of 13.8g/L with CBLs activity at 3391 U/L was achieved after incubation at room temperature (RT,30 ± 2°C) for 140h in 50% POME medium, pH 7.0, containing 1.23% (w/v) ammonium sulfate. Bacterium promoted yeast growth to achieve bioremediation with 87.9% O&G removal and 84.5% COD removal. Time course study showed that the CBLs activity was highest at 24h cultivation (4103 U/L) and retained 80% and 60% of activities at 4°C and RT after 5weeks of storage. The CBLs application successfully yielded 77.3% biodiesel from oleic acid (esterification) and 86.4% biodiesel from palm oil (transesterification) within 72h in solvent-free systems. This study highlights that yeast-bacterium co-culture and POME should receive more attention for potential low-cost CBLs production through bioremediation, i.e., O&G and COD removals, while the CBLs as biocatalysts are promising for significant contribution to an effective strategy for economic green biodiesel production.

Effect of liposome composition on β-blocker interactions studied by capillary electrokinetic chromatography.

Liposome capillary electrokinetic chromatography was used to investigate the interactions between three β-blockers of different hydrophobicity and various liposome solutions. The studied β-blockers comprised alprenolol, propranolol, and carvedilol. The composition of the liposome solutions, containing 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, 1,2-dioleoyl-sn-glycero-3-phos-phoethanolamine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine, and cholesterol in various molar ratios, was designed by a response surface methodology-central composite design approach. Subsequently, after conducting the liposome capillary electrokinetic chromatography experiments and determining the retention factors from the electrophoretic mobilities of the compounds, and further calculating the distribution coefficients, an analysis of variance was performed. After extracting the statistical models, optimal operational conditions were obtained based on the developed models. To further investigate the interactions between the β-blockers and the liposomes, nanoplasmonic sensing experiments were carried out on two different liposome systems. The overall results demonstrate the strong influence of cholesterol and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine on the distribution coefficients.