Search Results (79)

As manufacturing demands for challenging-to-machine metallic materials continue to evolve, the performance of cutting tools has emerged as a critical limiting factor. The synergistic application of micro-texture and coating in cutting tools can improve various properties. For the processing of existing micro-texture, because of the fast cooling and heating processing method of laser, there are defects such as remelted layer stacking and micro-cracks on the surface after processing. This study introduces a preheating-assisted technology aimed at optimizing the milling performance of textured coated tools. A milling test platform was established to evaluate the performance of these tools on titanium alloys under thermally assisted conditions. The face-centered cubic response surface methodology, as part of the central composite design (CCD) experimental framework, was employed to investigate the interaction effects of micro-texture preparation parameters and thermal assistance temperature on milling performance. The findings indicate a significant correlation between thermal assistance temperature and tool milling performance, suggesting that an appropriately selected thermal assistance temperature can enhance both the milling efficiency of the tool and the surface quality of the titanium alloy. Utilizing the response surface methodology, a multi-objective optimization of the textured coating tool-preparation process was conducted, resulting in the following optimized parameters: laser power of 45 W, scanning speed of 1576 mm/s, the number of scans was 7, micro-texture spacing of 130 μm, micro-texture diameter of 30 μm, and a heat-assisted temperature of 675.15 K. Finally, the experimental platform of optimization results is built, which proves that the optimization results are accurate and reliable, and provides theoretical basis and technical support for the preparation process of textured coating tools. It is of great significance to realize high-precision and high-quality machining of difficult-to-machine materials such as titanium alloy. Full article

The increasing presence of pesticide residues in aquatic environments poses a significant threat to ecosystems and human health, necessitating the development of effective removal technologies. In this study, Zeolitic Imidazolate Framework-8 (ZIF-8) was investigated as adsorbent for Linuron, a widely used herbicide. The material was synthesized via a hydrothermal method and underwent thorough physico-chemical characterization, confirming its intrinsic properties. Adsorption experiments were conducted under systematically varied conditions using a Central Composite Face-Centered (CFC) experimental design, evaluating the effects of temperature, Linuron concentration, ionic strength on adsorption efficiency. The Response Surface Methodology (RSM) revealed that temperature and Linuron concentration were the most influential variables. A quadratic effect of ionic strength and a significant interaction between Linuron concentration and ionic strength were also observed. The fitted quadratic regression model exhibited excellent predictive performance (R² = 0.909; Q² = 0.755), and analysis of variance (ANOVA) confirmed its significance (p < 0.001) with a non-significant lack of fit. Maximum Linuron removal (>95%) was achieved at elevated temperature, moderate concentration, and intermediate ionic strength. These findings highlight the potential of ZIF-8 as a tunable and high-efficiency adsorbent for the remediation of pesticide-contaminated water, demonstrating the value of RSM-based optimization in designing adsorption processes. Full article

Herein, a simple and effective analytical method was developed to monitor etoricoxib concentrations in human urine samples. Etoricoxib is a nonsteroidal anti-inflammatory drug for pain and inflammation relief in conditions such as osteoarthritis and rheumatoid arthritis. To determine its concentration, fabric phase sorptive extraction (FPSE) was combined with high-performance liquid chromatography and diode array detection (HPLC-DAD). FPSE is a green sample preparation technique that utilizes sol–gel-coated fabric substrates as extraction devices, offering numerous benefits in bioanalysis. Initially, different materials were tested for their affinity towards etoricoxib. The most critical FPSE parameters (i.e., sample amount, stirring rate, and adsorption time) were optimized using a face-centered central composite design (FC-CCD), while the remaining ones were explored by means of the one-variable-at-a-time approach. Afterwards, the analytical method was validated in terms of its selectivity, linearity, sensitivity, accuracy, and precision, while the environmental sustainability and the practicality of the method were also examined. The limit of detection was 0.03 μg mL⁻¹, and the lower limit of quantification was 0.10 μg mL⁻¹. The relative standard deviation was less than 7.2% in all cases, showing good precision. The proposed approach was successfully used to monitor urinary etoricoxib concentrations in real samples obtained from a volunteer after oral drug administration. Full article

The present work intends to assess the impact of trochoidal toolpath rounding radius loop adjustments on surface roughness, nose radius wear, and resultant cutting force during end milling of AISI D3 steel. Twenty experimental trials have been performed utilizing a face-centered central composite design through a response surface approach. Artificial Neural Network (ANN) models were built to forecast outcomes, utilizing four distinct learning algorithms: the Batch Back Propagation Algorithm (BBP), Quick Propagation Algorithm (QP), Incremental Back Propagation Algorithm (IBP), and Levenberg–Marquardt Back Propagation Algorithm (LMBP). The efficacy of these models was evaluated using RMSE, revealing that the LMBP model yielded the lowest RMSE for surface roughness (Ra), nose radius wear, and resultant cutting force, hence demonstrating superior predictive capability within the trained dataset. Additionally, a Genetic Algorithm (GA) was employed to ascertain the optimal machining settings, revealing that the ideal parameters include a cutting speed of 85 m/min, a feed rate of 0.07 mm/tooth, and a rounding radius of 7 mm. Moreover, the detachment of the coating layer resulted in alterations to the tooltip cutting edge on the machined surface as the circular loop distance increased. The initial arc radius fluctuated by 33.82% owing to tooltip defects that alter the edge micro-geometry of machining. The measured and expected values of the surface roughness, resultant cutting force, and nose radius wear exhibited discrepancies of 6.49%, 4.26%, and 4.1%, respectively. The morphologies of the machined surfaces exhibited scratches along with laces, and side flow markings. The back surface of the chip structure appears rough and jagged due to the shearing action. Full article

The present investigation aimed to formulate and optimize sustained release proliposome dry powder for inhalation of Voriconazole (VZ) and its in vitro and in vivo evaluation. The proliposome-based dry powder for inhalation was formulated by spray drying technique using Phospholipon 90H and cholesterol in the lipid phase, mannitol as a carrier, and L-leucine as a dispersing agent. A face-centered central composite design was used to study the influence of factors on responses, vesicle size, VZ entrapment efficiency, and drug release. The optimized formulation was further characterized by FTIR, FESEM, DSC, XRD, and evaluated for in vitro drug release, in vitro aerosol deposition, and in vivo lung retention study in Wistar rats. For the optimized batch F-5 proliposome formulation, vesicle size was observed as 191.7 ± 0.049 nm with PDI 0.328 ± 0.009, entrapment efficiency as 72.94 ± 0.56%, and cumulative drug release after 8 h of dissolution was 82.0 ± 0.14%. The median mass aerodynamic diameter (MMAD) generated by optimized formulation F5 was significantly lower (3.85 ± 0.15 µm, p < 0.0001) as compared to spray-dried voriconazole (SD-VZ) (8.35 ± 0.23 µm). In vivo studies demonstrated a profound enhancement in lung retention (3.8-fold) compared to SD-VZ and oral VZ dispersion. Conclusively, proliposome formulation of voriconazole is a plausible and convincing approach for pulmonary fungal infections, considering its sustained release behaviour and prolonged lung retention. Full article

The electro-oxidation of p-Benzoquinone (p-BQ) was investigated in a flow-by reactor (FM01-LC) without separation, with two boron-doped diamond (BDD) electrodes as both the anode and cathode, in batch recirculation mode. The optimal operating conditions were determined using response surface methodology, specifically a face-centered central composite design. The initial pH (pH₀) and applied current density (j) were evaluated as factors, while the p-BQ (η (%)) served as the response variable. The optimal conditions, a pH₀ of 6.52 and a j of 0.124 A/cm², achieved a maximum removal efficiency of 97.32% after 5 h of electrolysis. The specific energy consumption and total operating cost were 127.854 kWh/m³ and USD 3.7 USD/L, respectively. Full article

Buccal drug delivery systems often struggle with poor drug solubility, limited adhesion, and rapid clearance, leading to suboptimal therapeutic outcomes. To address these limitations, we developed a novel hybrid eutectogel composed of xanthan gum (XTG), hyaluronic acid (HA), and a Natural Deep Eutectic Solvent (NADES) system (choline chloride, sorbitol, and glycerol in 2:1:1 mole ratio), incorporating 2.5% ibuprofen (IBU) as a model drug. The formulation was optimized using a face-centered central composite design to enhance the rheological, textural, and drug release properties. The optimized eutectogels exhibited shear-thinning behavior (flow behavior index, n = 0.26 ± 0.01), high mucoadhesion (adhesiveness: 2.297 ± 0.142 N·s), and sustained drug release over 24 h, governed by Higuchi kinetics (release rate: 237.34 ± 13.61 μg/cm²/min^1/2). The ex vivo residence time increased substantially with NADES incorporation, reaching up to 176.7 ± 23.1 min. An in vivo anti-inflammatory evaluation showed that the eutectogel reduced λ-carrageenan-induced paw edema within 1 h and that its efficacy was sustained in the kaolin model up to 24 h (p < 0.05), achieving comparable efficacy to a commercial 5% IBU gel, despite a lower drug concentration. Additionally, the eutectogel presented a minimum inhibitory concentration for Gram-positive bacteria of 25 mg/mL, and through direct contact, it reduced microbial viability by up to 100%. Its efficacy against Bacillus cereus, Enterococcus faecium, and Klebsiella pneumoniae, combined with its significant anti-inflammatory properties, positions the NADES-based eutectogel as a promising multifunctional platform for buccal drug delivery, particularly for inflammatory conditions complicated by bacterial infections. Full article

Chitosan nanoparticles are nontoxic polymers with diverse biomedical applications. Traditional nanoparticle synthesis often involves harmful chemicals or results in reduced desirable properties, sparking interest in green synthesis methods for nanoparticle production. Utilizing plant-based phytochemicals as reducing and capping agents offers advantages like biocompatibility, sustainability, and safety. This study explored Blumea balsamifera leaf extract for chitosan nanoparticle (CNP) synthesis. CNPs were synthesized using pH-induced gelation and characterized by DLS and SEM. B. balsamifera extract, prepared using ethanol, achieved a total phenolic content of 19.37 ± 6.35 mg GAE/g dry weight. DLS characterization revealed a broad size distribution, with an average particle diameter of 908.9 ± 93.6 nm and peaks at 11.11 ± 0.97 nm, 164.45 ± 6.13 nm, and 1672.04 ± 338.75 nm. SEM measurements showed spherical particles with a diameter of 56.8–63.0 nm. UV-Vis analysis, with an absorption peak at 286.5 ± 0.5 nm, was used to optimize CNP biosynthesis through a Face-Centered Central Composite Design (FCCCD). Higher concentrations of B. balsamifera extract (0.05 g/mL) and chitosan (19.1 mg/mL) maximized nanoparticle yield with a mass of 100 μg/mL. Antibacterial testing against E. coli demonstrated a minimum inhibitory concentration of 25 μg/mL. B. balsamifera extract effectively synthesized nanochitosan particles, showing potential for antibacterial applications. Full article

This study addresses the environmental challenge of surfactant removal from wastewater, focusing on the increased surfactant use during the COVID-19 pandemic. Polymeric waste, specifically polyurethane (PU) and polyamide (PA), was repurposed for surfactant adsorption to mitigate these environmental impacts. Methods included preparing surfactant solutions of sodium linear alkylbenzene sulfonate (LAS) and dodecyl pyridinium chloride (DPC) and the mechanical processing of polymeric residues. PU and PA were characterized by FTIR-ATR and by the pH at the point of zero charge, which yielded pH = 8.0 for both polymers. The adsorption efficiency was optimized using a central composite face-centered design, varying pH, temperature, and time. The results indicated that PU and PA effectively adsorbed anionic and cationic surfactants, with specific conditions enhancing performance. From the optimized experimental conditions, four assays were carried out to evaluate the adsorption isotherms and kinetics. Among the fitted models, the SIPS model was the most representative, indicating a heterogeneous surface. Regarding LAS, the maximum adsorption capacity values were ~90 and 15 mg g⁻¹, respectively, for PU and PA. Considering the DPC surfactant, lower values were obtained (~36 mg g⁻¹ for PU and 16 mg g⁻¹ for PA). The results are satisfactory because the adsorbents used in this study were second-generation waste and were used without treatment or complex modifications. The study concluded that using polymeric waste for surfactant removal offers a sustainable solution, transforming waste management while addressing environmental contamination. This approach provides a method for reducing surfactant levels in wastewater and adds value to otherwise discarded materials, promoting a circular economy and sustainable waste reuse. Full article

Rice bran (RB) is a rice processing by-product recognized to be a source of bioactive compounds, including γ-oryzanol and fatty acids, which have interesting bioactivities such as antioxidant and anti-inflammatory effects. This study aims to optimize the supercritical fluid extraction process for recovering these high-value compounds from rice bran with improved bioactivity. A Central Composite Face-Centered Design was employed to optimize the extraction process by varying the temperature (40–80 °C) and pressure (200–500 bar). The optimal extraction conditions were identified at 500 bar and 62 °C that led to the extraction of 17.3% mass yield with 784.5 mg of fatty acids and 36.6 mg of γ-oryzanol per gram of extract, striking a balance between extraction yield and bioactive concentrations. When compared with conventional extractions with n-hexane, supercritical fluid extraction showed similar global yield (18.0 vs. 17.3%) and FA concentration (130.14 vs. 135.70 mg/g of RB) but higher selectivity and extraction yield for γ-oryzanol (18.0 vs. 36.4 mg/g extract; 3.3 vs. 6.3 mg/g of RB). Cellular antioxidant activity assays showed that both extracts reduced the quantity of reactive oxygen species (ROS) up to 50% in Caco-2 cells submitted to oxidative stress. Importantly, supercritical fluid extract was more effective in inhibiting colorectal cancer cell growth (EC50 = 0.9 mg/mL vs. 1.15 mg/mL) than the hexane extract, and this effect was more pronounced than that obtained for pure γ-oryzanol in the same concentration range. These findings highlight the potential of supercritical fluid technology to develop rice bran extracts with antioxidant and antiproliferative properties, underlining the promising applications of this technology in the field of natural product extraction. Full article

Cinnamomum iners Reinw. ex Blume has long been recognized as a plant with food and medicinal uses. This study was designed to optimize the MAE process to produce a high-value, polyphenol-rich crude extract from cinnamon leaves (PCL). The primary goal was to apply response surface methodology (RSM) with a face-centered central composite design (FCCD) to identify the ideal conditions for microwave-assisted extraction (MAE). Key factors such as the MAE time, microwave power, and solid-to-liquid ratio were examined to produce a polyphenol-rich crude extract from C. iners leaves. The resulting extracts were assessed for extraction yield, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. The results showed that MAE using a methanol solvent had a significant impact on antioxidant compound levels. The R² values for all responses, yield, TPC, TFC, and DPPH radical scavenging activity were 0.9497, 0.9494, 0.9199, and 0.9570, respectively, indicating that the developed quadratic polynomial models were accurate and suitable for analyzing MAE parameter interactions. The optimum MAE parameters were determined to be an MAE time of 25 min, microwave power of 214.24 W, and plant leaf–solvent ratio of 1:195.76 g/mL. In these optimized MAE conditions, the predicted extraction yield, TPC, TFC, and IC₅₀ of DPPH scavenging were 18.56%, 22.86 mg GAE/g, 13.89 mg QE/g, and 83.30 µg/mL, respectively. The enhanced efficiency of MAE comes from microwave-induced heating, which disrupts cell walls for faster compound release, making it more effective and time-efficient than traditional HRE for polyphenol extraction. This study demonstrated that polyphenols can be efficiently extracted from C. iners using MAE, producing a valuable extract with potential as a natural preservative in food and a skin-protective, anti-aging ingredient in cosmetics. Full article

In this study, nickel–cobalt (Ni–Co) coatings were fabricated via electrodeposition using a 2² central composite factorial design with two central and two axial points, totaling ten experiments. The effects of pH and current density on the coatings’ chemical composition and properties were evaluated. Coatings were characterized by microstructure, morphology, magnetic properties, and corrosion resistance. The results showed that pH significantly influenced chemical composition, while current density had no notable effect. Acidic pH produced cobalt-rich coatings (43–81 at.%), with uniform morphology, higher saturation magnetization, and lower corrosion resistance. Maximum cobalt content (81 at.%) resulted in a mixed face-centered cubic (fcc) + hexagonal close-packed (hcp) phase. Alkaline pH yielded nickel-rich coatings (89–95 at.%), featuring nodular morphology, lower magnetization, higher corrosion resistance, and, exclusively, the fcc phase. The highest polarization resistance (66.1 kΩ) occurred at pH 8.83 and 60 mA/cm², while resistance decreased with increasing cobalt content. The pH effect on deposition was linked to the formation of citrate complexes: ammonia and citrate complexes promoted nickel deposition under alkaline conditions, while stable cobalt complexes dominated in an acidic pH. These findings highlight the potential to tailor Ni–Co coatings for applications such as corrosion-resistant coatings (nickel-rich) or magnetic devices (cobalt-rich). Full article

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. Full article

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. Full article

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. Full article