Face-centered Central Composite Design Research Articles

Raisin Production by Convective-Microwave Dryer and Optimization of Ochratoxin A Content, Physicochemical, Sensory Characteristics, and Fungal Load of Raisin.

Raisins are so popular in the human diet as a nutritional and sweet snack. The quality of this foodstuff depends on drying conditions. To minimize ochratoxin A (OTA) content and yeast and mold content (YMC) in raisins with favorable physicochemical and sensory properties, the response surface methodology (RSM) and the face-centered central composite design (FCCD) were utilized. The independent variables were studied over a range of microwave power (0-220 W) and temperature air (35°C-55°C). The microwave power had a significant effect on the OTA value and YMC of dried samples. The use of microwaves in drying contributed to a higher decline in OTA content and YMC than in conventionally dried samples. The regression models detected for OTA content, acidity, pH, rehydration ratio (RR), water holding capacity (WHC), shrinkage, appearance, texture, acceptability, and YMC were significant and reliable. The desirability function was applied to recognize an optimized situation. The result of the RSM analysis showed the optimum conditions for obtaining healthy raisins with desired physicochemical and sensory attributes by microwave-convective dryer at 220 W microwave power and 38.68°C air temperature.

Malachite Green Dye Removal in Water by Using Biochar Produced from Pinus patula Pellet Gasification in a Reverse Downdraft Reactor

The efficiency of the elimination of malachite green dye (MG) in water was investigated using biochar (BC) obtained from Pinus patula wood pellets (BC-WP). The biomass was gasified, reaching a temperature of 391.07 °C near the reactor wall. During the adsorption tests, three independent factors were considered: the solution pH, BC concentration, and the BC particle size, which were optimized using different study ranges (4–10, 6–12 g/L, and 150–600 μm, respectively) at 30 min of contact time. The response surface methodology was used through a face-centered central composite design for this purpose. The experimental results were analyzed to develop a quadratic regression model that fitted the experimental data achieved. The highest removal percentage of MG by BC-WP (94.25%) was attained under a solution pH of 10, a BC concentration of 12 g/L, and an average BC particle size of 225 μm. Furthermore, the validated regression model was found to explain 94.72% of the obtained results, demonstrating the ability of BC-WP to remove the target dye. Thus, a new and sustainable alternative to conventional systems for treating dye-polluted water is proposed, utilizing the solid by-product of the thermochemical process, contributing to the circular economy.

Geometric Optimization of the Five-Point Double-Toggle System for the Clamping Unit of an Injection Molding Machine with the Response Surface Method

Injection molding is one of the most used processes for the manufacture of plastic products with high-volume capacity. The five-point double toggle mechanism is frequently employed in the clamping unit to augment the force generated by a linear actuator, thereby achieving the requisite clamping force. This is a crucial aspect that determines the productivity and quality of the finished product in the injection molding process. Nevertheless, the geometrical synthesis of this type of mechanism has not been sufficiently addressed with regard to its integration into the mold design and the opening/closing stroke. This paper presents a novel approach for analyzing and evaluating the impact of parameters pertaining to mechanism posture on its force amplification, employing the Taguchi method. The relationship between force amplification ratio and the most influential parameters is simplified with the Face-Centered Central Composite Design (FCCCD) method, thereby allowing the optimal posture of the mechanism at the mold-closing stage to be determined. With these optimal parameters, once the mold height and desired opening/closing stroke have been selected, the dimensions of the links in the mechanism can be calculated. The results demonstrate that there are numerous combinations of these parameters that can yield a high force amplification ratio, thus providing the designer with a range of options for the design of a clamping unit. The proposed method can be employed at the initial stage of the design process to obtain a preliminary design, thus preparing for the dynamic analysis or further optimization problems of the mechanism.

Sensitivity analysis of radiative hybrid nanofluid flow across a moving permeable wedge with variable surface temperature and magnetic field effects

PurposeIn the present article, sensitivity analysis was studied in the presence of the combined effects of thermal radiation, suction and magnetohydrodynamics (MHD) effects on a Nimonic 80A-Fe3O4/water hybrid nanofluid across moving a wedge with variable surface temperature and buoyancy effects.Design/methodology/approachThe governing equations were transformed using similarity transformations and solved using MATLAB bvp4c code and response surface methodology (RSM), with quadratic face-centred central composite design being implemented. All results and graphs were formulated after positive outcomes of our results with existing literature.FindingsAn increase in magnetic parameter (M) and velocity ratio parameter (R) resulted in an increase in velocity profiles and local Nusselt number, while a reverse trend was observed for temperature profiles. With radiation parameter Rd = 0.8, the local Nusselt number increased by 4.08% as the velocity ratio parameter increased from R = 0.0 to R = 0.5. The Nusselt number was found to be most sensitive to R, while the latter produced negative sensitivity on skin friction coefficient. The skin friction coefficient for the hybrid nanofluid model increased by 35.39% compared to the regular fluid model, with a very low standard deviation value of 10−4. The Model F-value for Nusselt number model was found to be 939278.49 with a noise ratio of 3618.711. Skin friction coefficient was found to be most sensitive with respect to changes in the parametric values of M.Research limitations/implicationsNimonic 80A being a super-alloy of nickel-iron-chromium and built in high frequency melting, it can work up to 1500°F and is extensively used in automobile exhaust valves.Practical implicationsThe present study finds numerous applications in biotoxicity studies, medical industries, water heaters and the forging of hot exhaust valve heads.Originality/valueIn view of various applications of our present study, there remains a gap in examining the sensitivity analysis of a hybrid nanofluid flow model across a moving permeable wedge using the Tiwari–Das model, which required clinical investigations numerically and statistically.

FORMULATION AND CHARACTERISATION OF RISEDRONATE SODIUM SUBLINGUAL SPRAY

Objective: To formulate a propellant-free sublingual spray of Risedronate sodium, addressing issues of gastrointestinal side effects associated with current oral formulations and improving patient compliance. Methods: Initially, a fractional factorial design was used to screen variables, followed by a face-centered central composite design for optimization. Formulation batches were characterized by spray pattern, spray angle, leak test, prime test, drug delivery uniformity, drug content per spray, and ex-vivo permeation study. Results: The optimized batch O1 exhibited an ovality ratio of 1.1, a spray angle of 640, and a drug permeation percentage of 4. In vivo absorption analysis revealed that the relative bioavailability of optimized batch O1 was 2.27 times higher than that of the plain drug solution. Compatibility of the product pack with excipients and the drug was confirmed through stability studies of batch O1. Conclusion: The study concluded that Risedronate sodium sublingual spray presents a promising alternative to oral administration, potentially reducing gastrointestinal side effects and enhancing patient compliance.

Development and Optimization of Transferosomal Gel for Efficient Topical Delivery of Berberine Hydrochloride

Background: Berberine is an isoquinoline alkaloid with potent anti-inflammatory effects. However, its therapeutic efficacy is often restricted by its poor solubility, absorption, and permeability, especially in topical applications. Transferosomes are elastic vesicular carriers with high skin permeability values and retention, making them suitable for encapsulating hydrophilic and lipophilic actives. Objective: The objective of this research was to develop a transferosome-based topical gel formulation of Berberine hydrochloride (BER) to improve its skin permeability and anti-inflammatory efficacy. Method: The thin film hydration method was used to formulate the BER transferosomes. The effects of independent variables, amount of BER in lipid phase (X1), and lipid (Phospholipon 90G) to surfactant ratio (X2) on BER entrapment and vesicle size were studied using face-centered central composite design. The characterization was performed using differential scanning calorimetry, transmission electron microscopy, and X-ray diffraction. The optimized batch (F5) was incorporated in Carbopol gel and further investigated for viscosity, in vitro and ex-vivo diffusion, skin retention by tape stripping, and in-vivo anti-inflammatory efficiency. Results: The formulation optimized with 50 mg of drug and a 5:1 lipid-to-surfactant ratio (F5) demonstrated higher drug entrapment efficiency (72.11%) and lower vesicle size (77.9 nm). TEM validated the spherical vesicle morphology, whereas DSC and XRD analysis confirmed the molecular entrapment of BER within the phospholipid vesicles. The transferosomal gel demonstrated improved BER diffusion (0.63 mg/cm2) confirmed by in vitro and ex-vivo diffusion experiments that revealed a 6-fold increase in flux and permeability coefficient (0.1053 mg. cm-2.h-1). The drug release from transferosome gel was non-Fickian in nature (n = 0.6575), indicating an integration of diffusion and erosion processes. Furthermore, BER transferosomal gel displayed substantial anti- inflammatory activity in rats (p < 0.001). result: The independent variables exerted a substantial impact on drug entrapment and transferosome vesicle size. The optimized batch (F5) exhibited 72.11 % of BER entrapment and 77.9 nm vesicle size. DSC studies indicated molecular dispersion of BER in phospholipon G. The change in BER crystalline state was indicated by the XRD study. In vitro, diffusion study of Transferosome gel formulation indicated the sustained release by a non-fickian mechanism. Ex vivo skin permeation revealed significant improvement in BER permeation (p< 0.05). Further, the tape-stripping method revealed higher BER skin permeability. In-vivo anti-inflammatory efficacy of BER transferosome gel was significantly higher as compared to plain BER gel. Conclusion: The findings demonstrated the potential of transferosomal gel as a promising approach for efficient drug delivery and therapeutic efficacy.

Enhancing Indian onion (Allium Cepa L. var. aggregatum) extraction by microwave hydrodiffusion and gravity (MHG) method: Parametric study and optimization using FCCD design

The aim of this study is to extract essential oil from Indian onion bulbs (Allium Cepa L. var. aggregatum) using the microwave hydrodiffusion-gravity (MHG) method. The operating parameters considered include drying pre-treatment, material size (1-3 cm), microwave power (300-600 W), and extraction time (15-75 min). Optimal extraction conditions were identified through a two-stage process: initially screening data using a full factorial design, followed by process optimization using a face-centred central composite design (FCCD). The oil yield increased with extraction time up to a certain point, after which it plateaued, indicating no further yield improvements. The size of the material had an impact on how well microwave energy transferred; smaller particles provided larger surface areas, which improved extraction efficiency. Furthermore, the reduction in moisture content due to drying directly affected essential oil production, leading to higher yields. Sudden temperature increases could negatively impact oil quality, making temperature control during extraction critical. The microwave power level also played a significant role in the extraction process. The highest oil yield, 2.78%, was obtained with an extraction time of 75 min, a microwave power of 600 W, and a material size of 1 cm. Additionally, the extracted onion oil contained cyclohexanol, 5-methyl-2-(1-methylethenyl), and Z-citral.

Influence of processing variables on fabrication of AA7475/B4C/Al2O3 hybrid surface composites via FSP

The motive of this research is to fabricate AA7475/B4C/Al2O3 hybrid surface composites (HSCs) using friction stir processing (FSP) for various applications in aerospace, marine, and automotive industries. The research systematically varied key processing variables, including rotational speed (900–1300 rpm), feed rate (30–60 mm/min), and reinforcement ratios (from 30% B4C and 70% Al2O3 to 70% B4C and 30% Al2O3), to optimize responses such as ultimate tensile strength (UTS), tensile elongation (TE), and microhardness (MH). A face-centered central composite design (FCCCD) of response surface methodology (RSM) was employed to develop mathematical models correlating the input parameters with the response variables. An analysis of variance (ANOVA) was conducted to assess the effects and interactions of the processing parameters on the composite properties. A validation test confirmed the reliability of these optimal conditions. ANOVA results indicated that the tool rotational speeds had the most significant effect on the tensile, ductility, and hardness properties of the HSCs. However, changes in feed rate and reinforcement ratio had minimal impact on these properties. The study identified optimal conditions for different responses: UTS of 452.62 MPa, TE of 6.89%, and MH of 168.52 HV at a rotational speed of 1300 rpm, feed rate of 45 mm/min, and a 50:50% reinforcement ratio (50% B4C and 50% Al2O3). The HSCs fabricated at 1300 rpm, 45 mm/min, and a 50:50% reinforcement ratio exhibited significant necking before failure, leading to a ductile failure mode.

Influence of multi-stress factors on the growth of Chlorella pyrenoidosa and Scenedesmus abundans using response surface methodology.

This study evaluated the biofuel production potential of two algal species, Chlorella pyrenoidosa and Scenedesmus abundans, under stress conditions induced by nutrient supplementation or starvation at varying light intensities. Central composite face-centered design response surface methodology (CCFD-RSM) was employed to optimize stress conditions by varying the sodium nitrate (NaNO3), potassium dihydrogen phosphate (KH2PO4), dipotassium hydrogen phosphate (K2HPO4), cultivation time, and light intensity. The study included both C. pyrenoidosa and S. abundans, which presented increased biomass yields when subjected to nutrient starvation. Under the optimized conditions, the dry biomass yield was 98.26mg/L for C. pyrenoidosa and 110mg/L for S. abundans. Lipid yields were approximately 22.47% for C. pyrenoidosa and 29.06% for S. abundans under these optimized growth conditions. The optimized parameters for maximum biomass and lipid production were identified as C. pyrenoidosa, and the optimized conditions required 0.805g/L NaNO3, 0.052g/L K2HPO4, 0.099g/L KH2PO4, 17days of culture, and 5168.39lx of light intensity. For S. abundans, the optimal conditions were 1.065g/L NaNO3, 0.071g/L K2HPO4, 0.058g/L KH2PO4, 22days of cultivation, and 2897lx of light intensity. Overall, both C. pyrenoidosa and S. abundans have emerged as promising candidates for sustainable biodiesel production, highlighting their potential under stress conditions induced by nutrient modulation and variable light intensities.

DEVELOPING A NUMERICAL MODEL TO OPTIMISE THE LASER-BEAM-WELDING PARAMETERS FOR JOINING TITANIUM TUBES

In this work Nd:YAG laser beam welding (LBW), which requires a low heat input, was applied to join grade-2 titanium tubes. The pulse duration and pulse energy were varied according to a two-factor three-level central composite face-centred (CCFC) design to join grade-2 titanium tubes. A numerical model was developed to correlate LBW process parameters and ultimate tensile strength (UTS). Validation of the developed model was done using the analysis of variance. Pulse duration has a more significant impact compared to pulse energy. The highest and lowest values of each process parameter produced a weak UTS, which was less than 338 MPa. The change in the UTS for each process parameter was analysed with metallurgical studies of the joints. Optimised process parameters for improved UTS were identified and reported.

CTAB-Si Nanoparticles Derived from Rice Husk Ash for Nitrate Ions Removal in Simulated Wastewater

In this study, silica (Si) nanoparticles derived from rice husk ash is coated with cetyltrimethylammonium bromide (CTAB), a cationic surfactant, and used as adsorbent of nitrate ion in wastewater. CTAB functionalized Si (CTAB-Si) nanoparticles were characterized using scanning electron microscope (SEM), energy dispersive X-Ray (EDX), dynamic light scattering (DLS) Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The synthesized CTAB-Si nanoparticles has a non-spherical shape, with visible polydispersity and is amorphous with average particle size of 72nm. It showed stretching vibrations of silanol at 963cm-1, siloxane at 1073cm-1, sharp peaks at 2852cm-1 and 2922cm-1 due to the methylene tail of CTAB and amine peak at 1,384cm-1. An ∼80% nitrate removal and adsorption capacity of 7.98 mg NO3/g CTAB-Si nanoparticles was obtained at optimized condition using Face Centered Central Composite Design (FC-CCD) at pH 4, 50 mgL-1 of adsorbate concentration, 0.2 gL-1 adsorbent dose and 30 minutes contact time. The adsorption isotherm and kinetic models fits well in Langmuir model and Pseudo second order with a R2 of 0.984 and 0.999 respectively. The efficiency of the nanoparticle after 5 adsorption cycles was ∼50% nitrate removal.

Experimental investigation of material extrusion additive manufacturing of copper with high powder loading rate

Beam-based additive manufacturing has challenges in fabricating pure copper due to high reflectivity. Material extrusion additive manufacturing (MEAM) avoids these issues with low costs, making it suitable to fabricate complex structures in pure copper. In this work, the effects of several printing parameters on the geometry of the samples are studied from single line, thin wall to cube using homemade copper feedstocks with high powder loading rate (65 vol%). The results show that the single line is most affected by layer thickness, while the thin wall has stricter requirements for printing temperature and printing speed. The geometric accuracy of the cube demonstrates large parametric tolerance due to the overlap and support between the lines. Central composite face-centered (CCF) design and central composite design (CCD) are used to analyze and optimize process parameters for densification. The measured porosity at the optimized printing (printing temperature = 177 °C, air gap = −0.05 mm, layer thickness = 0.3 mm) and sintering parameters (sintering temperature = 1045 °C, holding time = 4 h) is in good agreement with the predicted values. Air gap and sintering temperature have the greatest influence on the porosity, and other parameters within a certain range of on-demand adjustments do not have a significant effect. The ultimate tensile strength and elongation of the sintered samples under the optimal parameters are 153.9 ± 6.1 MPa and 31.36 ± 3.24%, respectively. No printing defects are found at the fracture and the elongation is good, showing the effectiveness of the parameter optimization.

Unlocking Nature’s Potential: Modelling Acacia melanoxylon as a Renewable Resource for Bio-Oil Production through Thermochemical Liquefaction

This study is focused on the modelling of the production of bio-oil by thermochemical liquefaction. Species Acacia melanoxylon was used as the source of biomass, the standard chemical 2-Ethylhexanol (2-EHEX) was used as solvent, p-Toluenesulfonic acid (pTSA) was used as the catalyst, and acetone was used for the washing process. This procedure consisted of a moderate acid-catalysed liquefaction process and was applied at 3 different temperatures to determine the proper model: 100, 135, and 170 °C, and at 30-, 115-, and 200-min periods with 0.5%, 5.25%, and 10% (m/m) catalyst concentrations of overall mass. Optimized results showed a bio-oil yield of 83.29% and an HHV of 34.31 MJ/kg. A central composite face-centred (CCF) design was applied to the liquefaction reaction optimization. Reaction time, reaction temperature, as well as catalyst concentration, were chosen as independent variables. The resulting model exhibited very good results, with a highly adjusted R-squared (1.000). The liquefied products and biochar samples were characterized by Fourier-transformed infrared (FTIR) and thermogravimetric analysis (TGA); scanning electron microscopy (SEM) was also performed. The results show that invasive species such as acacia may have very good potential to generate biofuels and utilize lignocellulosic biomass in different ways. Additionally, using acacia as feedstock for bio-oil liquefaction will allow the valorisation of woody biomass and prevent forest fires as well. Besides, this process may provide a chance to control the invasive species in the forests, reduce the effect of forest fires, and produce bio-oil as a renewable energy.

Enhanced Glycerolysis of Fatty Acid Methyl Ester by Static Mixer Reactor.

This study investigates the synthesis of monoglycerides (MGs) and diglycerides (DGs) from glycerol (G) and fatty acid methyl ester (FAME) using a static mixer reactor (SMR), which combines a static mixer (SM) with a reactor tank. The SMR integrates Kenics static mixers (KSM) and low-pressure drop static mixers (LPDSM) with varying length-to-diameter ratios (L/D = 1.0 and 1.5). Keys glycerolysis parameters, including the G:FAME molar ratio of 2:1-3:1, 2-3 wt % potassium hydroxide (KOH), and reaction time of 30-90 min at 150 °C were systematically explored. The SMR design allows precise control over the reaction time without altering the feed flow rate or tube length and avoiding agitator leakage. The optimal operating conditions, determined through a face-centered central composite design, resulted in 71.35% MGs and 14.20% DGs at a 3:1 molar ratio of G to FAME, 3 wt % KOH, 60 min, and 150 °C using an LPDSM with an L/D of 1.5. In comparison, an LPDSM with an L/D of 1 achieved 79.28% MGs and 10.17% DGs under the same conditions. When applied to purified crude glycerol, these conditions yielded 61.09% MGs and 23.44% DGs. The study found that a lower L/D ratio improved the mixing efficiency but increased the pressure drop. The SMR demonstrated superior performance in glycerolysis compared with conventional stirred tank reactors and ultrasonic probe reactors, indicating its potential for enhanced industrial application.

Myco-Biosynthesis of Silver Nanoparticles, Optimization, Characterization, and In Silico Anticancer Activities by Molecular Docking Approach against Hepatic and Breast Cancer.

This study explored the green synthesis of silver nanoparticles (AgNPs) using the extracellular filtrate of Fusarium oxysporum as a reducing agent and evaluated their antitumor potential through in vitro and in silico approaches. The biosynthesis of AgNPs was monitored by visual observation of the color change and confirmed by UV-Vis spectroscopy, revealing a characteristic peak at 418 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses showed spherical nanoparticles ranging from 6.53 to 21.84 nm in size, with stable colloidal behavior and a negative zeta potential of -15.5 mV. Selected area electron diffraction (SAED) confirmed the crystalline nature of the AgNPs, whereas energy-dispersive X-ray (EDX) indicated the presence of elemental silver at 34.35%. A face-centered central composite design (FCCD) was employed to optimize the biosynthesis process, yielding a maximum AgNPs yield of 96.77 µg/mL under the optimized conditions. The antitumor efficacy of AgNPs against MCF-7 and HepG2 cancer cell lines was assessed, with IC50 values of 35.4 µg/mL and 7.6 µg/mL, respectively. Molecular docking revealed interactions between Ag metal and key amino acids of BCL-2 (B-cell lymphoma-2) and FGF19 (fibroblast growth factor 19), consistent with in vitro data. These findings highlight the potential of biologically derived AgNPs as promising therapeutic agents for cancer treatment and demonstrate the utility of these methods for understanding the reaction mechanisms and optimizing nanomaterial synthesis.

Impact of Toolpath Pitch Distance on Cutting Tool Nose Radius Deviation and Surface Quality of AISI D3 Steel Using Precision Measurement Techniques.

The selection of the right tool path trajectory and the corresponding machining parameters for end milling is a challenge in mold and die industries. Subsequently, the selection of appropriate tool path parameters can reduce overall machining time, improve the surface finish of the workpiece, extend tool life, reduce overall cost, and improve productivity. This work aims to establish the performance of end milling process parameters and the impact of trochoidal toolpath parameters on the surface finish of AISI D3 steel. It especially focuses on the effect of the tool tip nose radius deviation on the surface quality using precision measurement techniques. The experimental design was carried out in a systematic manner using a face-centered central composite design (FCCD) within the framework of response surface methodology (RSM). Twenty different experiment trials were conducted by changing the independent variables, such as cutting speed, feed rate, and trochoidal pitch distance. The main effects and the interactions of these parameters were determined using analysis of variance (ANOVA). The optimal conditions were identified using a multiple objective optimization method based on desirability function analysis (DFA). The developed empirical models showed statistical significance with the best process parameters, which include a feed rate of 0.05 m/tooth, a trochoidal pitch distance of 1.8 mm, and a cutting speed of 78 m/min. Further, as the trochoidal pitch distance increased, variations in the tool tip cutting edge were observed on the machined surface due to peeling off of the coating layer. The flaws on the tool tip, which alter the edge micro-geometry after machining, resulted in up to 33.83% variation in the initial nose radius. Deviations of 4.25% and 5.31% were noted between actual and predicted values of surface roughness and the nose radius, respectively.

Anion exchange-HPLC method for evaluating the encapsulation efficiency of mRNA-loaded lipid nanoparticles using analytical quality by design

Lipid nanoparticles (LNPs) are emerging nucleic acid delivery systems in the development of mRNA therapeutics such as the severe acute respiratory syndrome coronavirus 2 vaccines. However, a suitable analytical method for evaluating the encapsulation efficiency (EE) of the LNPs is required to ensure drug efficacy, as current analytical methods exhibit throughput issues and require long analysis times. Hence, we developed and validated an anion-exchange HPLC method using Analytical Quality by Design. Three critical method parameters (CMPs) were identified using risk assessment and Design of Experiments: column temperature, flow rate, and sodium perchlorate concentration. The CMPs were optimized using Face-Centered Central Composite Design. The discriminating power of the optimized HPLC method and RiboGreen assay was comparable. The main advantage of this method is that LNPs can be directly injected into the HPLC system without bursting the LNPs loaded with encapsulated poly(A). The optimized HPLC method was validated as robust, high-throughput, and sufficiently sensitive according to the ICH Q2 guidelines. We believe our findings could promote efficient LNPs-based drug development.

Natural deep eutectic solvents for efficient recovery of bioactive compounds from by-product of industrial hemp processing: Pretreatment, modeling and optimization

Hempseed hull, an underutilized by-product of the hemp processing industry, is a valuable bio-based material. This study aims to optimize phenolic compound extraction by natural deep eutectic solvents (NADES) with enhanced antioxidant properties (DPPH, FRAP, ABTS). By utilizing a chemometric approach, the research was conducted in three stages: selecting high-extractability NADES, identifying crucial extraction variables via screening, and optimizing conditions using response surface methodology (RSM). Fractional factorial experimental design was employed to identify the important variables, while a face-centered central composite experimental design (CCD) was utilized in combination with response surface methodology (RSM) to determine the optimal extraction conditions. The optimal conditions were found using NADES based on L-proline and lactic acid (1:2 ratio) at 39°C for the liquid-solid ratio, 70°C for temperature, and 135 minutes for extraction time. By optimizing extraction conditions this study contributes to advancing our understanding of hempseed hulls' biochemical composition and its potential as bio-based material.

Comparative analysis of non-thermal technologies and solvent systems for the extraction and characterization of phytochemicals and antioxidants in Pandanus amaryllifolius

Pandanus amaryllifolius leaves (PAL) are known for their aroma and are also a rich source of natural phytochemicals. The purity, yield, and stability of phytochemicals depend upon the efficiency and selectiveness of the extraction method and the solvent used. In this study, the phytochemical and antioxidant activity of PAL were evaluated by using non-thermal extraction techniques, i.e., ultrasound (US) and cold plasma (CP). The extraction was evaluated using two different solvents: petroleum ether and 30 % ethanol. Face-centered central composite design was used to design the experimental parameters. The process parameters used were amplitude (30, 45, and 60 %) and treatment time (15, 30, and 45 min) for US, and voltage (10, 20, and 30 kV) and time (10, 20, and 30 min) for CP. The extraction efficiency of both the treatment methods and solvents was evaluated based on the quantification of total phenolics, flavonoids, terpenoids, chlorophyll content, and antioxidant activity. The damaged cell structure as observed from SEM images, confirmed the extraction of phytochemicals. The presence of phenolic and flavonoid compounds in the extract of PAL was confirmed from the FTIR analysis, revealing its nutritional and medicinal properties. Antioxidant activity was higher in case of 30 % ethanol as compared to petroleum ether. In the case of phenolic compounds, CP along with ethanol, had higher extraction efficiency. The use of non-thermal technology along with a suitable solvent can extract phytochemicals and antioxidants from PAL that can be further utilized for value-added product development.

Optimization of microwave-produced coal-derived char insulation foam using response surface methodology

A new char-based insulation foam (CIF) is developed using coal-derived pyrolysis char (PC) and lignin, a paper and pulp industry byproduct. In this study, CIF is prepared by adopting the microwave method and Response Surface Methodology (RSM) is utilized to optimize predictions about the properties such as thermal conductivity, foam texture, compressive strength, and pore distribution of CIF. The three independent variables including percent char content, lignin/char ratio, and foaming agent/polyol ratio are considered in the RSM methodology. The face-centered central composite design is selected to obtain 17 test runs. Optimization of the predicted responses is performed to find the recipe considering a composite desirability function. Confirmatory test results show agreement between the predicted and observed values, with the percent error ranging from 0.00 % to 11.35 %, thereby confirming the accuracy of the prediction equations. The optimized CIF exhibits a thermal conductivity of 0.0633 W/m.K and a compressive strength of 695 kPa making it comparable to or better than traditional building insulation products such as fiber insulation, polymer composite, particle board, and ceramic glass foam. Therefore, this new CIF has the potential to be used as an energy-saving insulation material for building envelopes.