Search Results (986)

Fe-based amorphous soft magnets have long been investigated with respect to alloy design and processing strategies to enhance saturation polarization (J_s) while preserving the amorphous phase essential for excellent soft magnetic properties and superior performance. This study demonstrates that Fe80B13Si7 melt-spun ribbons, containing a moderately high ferromagnetic fraction (~80 at%), display excellent amorphous stability, impressive soft magnetic behavior, and extremely low energy losses when processed under a highly efficient quenching atmosphere provided by helium. With the identical processing parameters, soft magnetic ribbons produced in helium gas provide a fully amorphous structure, whereas the ribbons synthesized in nitrogen undergo partial crystallization. The helium-quenched samples exhibit an exceptionally low mean coercivity (H_c) of ~1.3 A/m, in contrast to the nitrogen-quenched ones (mean H_c~14 A/m). The attained maximum permeability (μ_max) in helium (28.4 ± 1.3 (×10³)) is even comparable with commercial Metglas 2605SA1 (33.3 ± 4.8 (×10³)). The average saturation polarization (J_s) of the ribbons fabricated in both helium (~1.63 T) and nitrogen (~1.61 T) gases exceeds the commercial reference (~1.55 T). The helium environment showcases an excellent surface profile relative to nitrogen-induced quenching, which even shows a lower arithmetic mean surface height (S_a) than the reference material. Furthermore, the optimum annealing window for minimizing coercivity is found to lie approximately 15 to 20 K below the Curie temperatures (T_c) of the respective specimens. Core loss (P_core) measurements reveal substantial loss reduction in helium-quenched ribbons relative to nitrogen-quenched ones and even slightly lower than Metglas 2605SA1 at a lower polarization level (J~0.5 T). Therefore, this work establishes a comprehensive understanding of how helium and nitrogen gases, as quenching environments, influence the amorphous formation, magnetic softness, surface morphology, and energy losses of an alloy with a relatively high Fe content from the Fe-B-Si family to harness the material’s maximum potential. Full article

The generation of aerosols with narrow droplet-size distributions remains a key challenge in liquid atomization technologies used in agricultural, chemical-processing, and environmental applications. This study presents an experimental investigation of spray characteristics produced by an inertial rotary atomizer equipped with an internal hydrodynamic flow-conditioning system. The experiments were conducted using a Box–Behnken experimental design and Response Surface Methodology (RSM). Fifteen experimental runs, including three center-point replicates, were performed to evaluate the combined effects of the operating parameters. Liquid flow rate, rotor rotational speed, and spraying height were selected as independent variables. The response variables included the characteristic droplet diameters (d₁₀, d₅₀ and d₉₀), the Span coefficient, and droplet deposition density (N). Quadratic regression models were fitted to the experimental data to explore the influence of the operating parameters on spray characteristics; however, statistical diagnostics indicated limited predictive capability, and the models were therefore used primarily for exploratory interpretation of response trends within the investigated design space. The experimental results indicated that rotor speed exhibited the strongest tendency to influence droplet-size characteristics within the investigated operating range, while increasing liquid flow rate was associated with larger droplet diameters, consistent with the expected effect of increased liquid-film thickness. Within the investigated atomizer configuration, relatively narrow droplet-size distributions were experimentally observed under selected operating conditions. These observations are consistent with the hypothesis that internal hydrodynamic flow conditioning may contribute to liquid-film destabilization and subsequent breakup. However, its independent contribution cannot be isolated from the present experiments because an otherwise identical baseline atomizer without the flow-conditioning element was not tested. Within the model-predicted favorable operating region (liquid flow rate of 1.0 × 10⁻⁶ m³·s⁻¹, rotor rotational speed of 4600–5100 min⁻¹, and spraying height of 30 cm), the fitted response-surface model predicted a volume median droplet diameter of approximately 64 μm. Separately, the minimum experimentally observed Span coefficient was approximately 0.58, indicating a relatively narrow deposited-droplet-size distribution within the investigated operating range. This model-predicted region was not independently verified by a dedicated confirmation experiment and therefore should not be interpreted as an experimentally validated optimum. The proposed physical interpretation considers hydrodynamic flow conditioning as a plausible additional mechanism contributing to spray uniformity, although its quantitative validation requires dedicated flow diagnostics and CFD analysis. The obtained results characterize the spray behavior of the developed atomizer within the investigated operating domain and provide an experimental basis for future comparative studies aimed at quantifying the independent contribution of the internal flow-conditioning system. These findings provide experimental evidence supporting further investigation of this concept and may contribute to the development of rotary atomizers for precision agricultural spraying and other engineering applications requiring controlled droplet-size distributions. Full article

In this study, a composite adsorbent (CS-ABnt) based on activated bentonite and chitosan was prepared using a simple coating method in the form of beads designed to combine high adsorption performance with the ease of solid–liquid separation typical of bead-type materials, serving as a low-cost tetracycline adsorbent. The composite was characterized by FTIR, EDX, and zeta potential measurements, which confirmed successful chitosan coating of the bentonite surface and a marked shift in the point of zero charge (from pH 5.54 for chitosan to pH 7.32 for CS-ABnt). Batch adsorption experiments showed that tetracycline removal was strongly pH-dependent, with an optimum near pH 6, and that the CS-ABnt composite consistently outperformed its individual components (chitosan and activated bentonite) across all tested doses, contact times, and temperatures. Equilibrium data were best described by the Langmuir isotherm, yielding a maximum adsorption capacity of 49.11 mg·g⁻¹, while kinetic data followed the pseudo-second-order model, revealing that the rate-limiting step is chemisorption. The thermodynamic parameters (ΔG° < 0, ΔH° > 0, ΔS° > 0) indicated a spontaneous, endothermic adsorption process. Taken together, these results enabled a 95% removal efficiency of tetracycline to be achieved. Full article

Flocculation-sedimentation is a widely used solid–liquid separation process in mineral processing and wastewater treatment, yet its optimization remains challenging due to nonlinear interactions among reagents, solids, and operating conditions. This study presents a statistically rigorous multi-response optimization framework combining HuberT robust regression, canonical analysis, and the Derringer desirability function, and demonstrates its application to coal slurry water treatment as a case study. Coal slurry concentration, polyacrylamide (PAM) dosage, and CaCl₂ concentration were used as factors, with supernatant turbidity and initial settling velocity as responses. A central composite design (20 runs) was employed, and second-order models were fitted via HuberT M-estimation to mitigate the influence of potential outliers. Both the ln-transformed turbidity model (R² = 0.9887) and settling velocity model (R² = 0.9908) showed high significance and predictive capability. Canonical analysis confirmed that the turbidity response surface exhibits a true minimum within the design space, while the settling velocity surface has a saddle-point structure. HuberT weight diagnostics identified no downweighted runs for turbidity and two mildly influential runs for settling velocity, confirming overall data consistency. Multi-response optimization via the Derringer desirability function yielded a combined optimum (coal slurry 25.27 g/L, PAM 5.19 mg/L, CaCl₂ 2.07 g/L; desirability D = 0.8981) with predicted turbidity of 29.21 NTU and settling velocity of 13.26 mm/s. The proposed framework may be extended to other flocculation-sedimentation systems requiring simultaneous improvement of multiple, often conflicting, process responses, although this generalizability has not yet been empirically tested beyond the single coal slurry system examined here. Full article

Lasiodiplodia theobromae is an important postharvest fruit rot pathogen that reduces the shelf life and marketability of durian. This study developed an ultrasound-assisted submicron curcumin-removed turmeric oleoresin and chitosan coating and evaluated its antifungal activity against L. theobromae in ‘Ri 6’ durian. An optimum formulation of 250 g L⁻¹ CRTO and 11.18 g L⁻¹ chitosan was obtained using response surface optimisation and prepared with ultrasound energy input of 384 J mL⁻¹. The optimised dispersion showed a hydrodynamic droplet size of 514 nm, a low polydispersity index of 0.16, a positive ζ-potential of +38 mV, and an emulsification efficiency of 86.16%; it retained one of the highest degrees of visual homogeneity among the 15 design formulations after 7 months of storage at 25 °C. In vitro assays showed strong dose-dependent inhibition of L. theobromae, with mycelial growth suppressed by 98.4–100% at 0.10 C₀ and 0.20 C₀; the two concentrations did not differ significantly (p > 0.05). Lesion development on wounded-inoculated fruit was reduced by 84.8–88.6% in CRTO–chitosan-coated fruit compared with the untreated control. Ultrasound-assisted submicron CRTO–chitosan coating is therefore a promising natural strategy for controlling postharvest fruit rot caused by L. theobromae in ‘Ri 6’ durian. The study was limited to one cultivar and one harvest batch, and postharvest quality, sensory attributes, and long-term dispersion stability were not assessed. Full article

In high-density cities, limited roof and ground areas constrain conventional photovoltaic (PV) deployment. Vertical bifacial photovoltaic (bPV) modules offer an alternative by making good use of building and infrastructure surfaces while harvesting irradiance on both sides. This study develops an integrated module-level framework for evaluating tilted and vertical bPV modules. It couples two-sided anisotropic irradiance calculations with five-parameter electrical and steady-state thermal models. Unlike irradiance-only or configuration-specific assessments, the framework consistently compares bPV and monofacial PV (mPV) modules across tilt and azimuth configurations while jointly quantifying power output, module temperature, bifacial gain, and angular losses. Predicted power output agreed well with outdoor measurements across four representative mounting configurations, and annual predictions were comparable to PVsyst and SAM results. Applied to Hong Kong, the framework identified optimum tilt angles of approximately 20° for bPV and 18° for mPV modules. A vertical west-facing bPV module achieved 96.3% of the annual energy yield of optimally tilted mPV, with a bifacial gain of 67.2% and an angular-loss-related power loss of 4.8%. These results show that vertical bPV can approach optimally tilted mPV performance while utilizing otherwise unused building surfaces, supporting preliminary design decisions in land-constrained cities. Full article

In wheat threshing, reducing total grain loss and energy consumption is crucial for both economic and sustainable food security. This study investigates the effects of threshing drum type (straight and helical row), drum peripheral speed (36.73–48.98 m s⁻¹), and drum-concave clearance (35–50 mm) on total grain loss and specific fuel consumption in a stationary threshing machine using a full factorial design. The optimum machine settings (drum type, peripheral speed and drum–concave clearance) that simultaneously minimize these two outputs were then determined. We systematically compared three surrogate modelling approaches—Response Surface Model (RSM), Gaussian Process Regression (GPR), and Artificial Neural Network (ANN)—to identify the most effective method for small-dataset optimization in threshing machine design. The best model was selected through cross-validation, and optimization was performed using the NSGA-II multi-objective genetic algorithm. GPR yielded the highest prediction accuracy for both outputs (R² in prediction data: 0.99 for total grain loss and 0.91 for specific fuel consumption). Multi-objective optimization revealed a conflict between the two objectives; the best balance was achieved for the helical drum at a peripheral speed of approximately 41.5 m s⁻¹ and a drum–concave clearance of 50 mm (predicted total grain loss approximately 3.7%, specific fuel consumption approximately 2.98 mL kg⁻¹). Compared to the straight-row drum, the helical drum provided lower losses and fuel consumption, as well as approximately 3.5 times wider safe operating range. It should be noted that this optimum was predicted by the surrogate model and agreed closely with the best measured treatment; it was not confirmed by an independent validation experiment. The results demonstrated that combining a surrogate model with a genetic algorithm is an effective tool for optimizing threshing machine parameters. Full article

The high-temperature sealing reliability of flange–bolt–gasket systems is governed by the coupled gasket leakage, flange cracking, and bolt yielding. This study investigates a DN200 PN40 (nominal diameter 200 mm and nominal pressure 4.0 MPa) weld-neck flange assembly operating under 300 °C superheated steam at 4 MPa internal pressure. Exploiting the assembly’s 12-fold cyclic rotational symmetry, a 1/12 periodic-sector finite element model with steady-state thermal–structural sequential coupling was developed in ANSYS Workbench and validated against the Omiya–Sawa 3-inch weld-neck flange benchmark at two levels (Level 1: bolt load vs. experiment; Level 2: 250 °C gasket contact pressure vs. reference finite element method (FEM)), with maximum errors below 1.5% in both levels; the benchmark thus establishes the reliability of the modeling procedure rather than constituting a direct experimental validation of the DN200 PN40 configuration. Using a central composite design, second-order response surface models (RSM) and Kriging surrogate models were constructed and compared, followed by Sobol global sensitivity analysis, multi-objective optimization using the non-dominated sorting genetic algorithm II (NSGA-II), and decision-making using the technique for order preference by similarity to ideal solution (TOPSIS), with bolt preload F and gasket width b as design variables. Baseline analysis revealed a differential contact pressure distribution—lower at the inner radius and higher at the outer radius—driven by a −0.308° flange rotation, identifying the inner gasket edge as the critical sealing failure path. RSM outperformed Kriging for the primary objective (mean absolute percentage error (MAPE): 0.72% vs. 3.61%), and the Pareto front collapsed to b = 19 mm. The TOPSIS-recommended optimum (F = 59,942 N, b = 19.00 mm), verified by ANSYS back-substitution, increased the minimum gasket contact pressure by 31.01% while reducing the flange membrane-plus-bending stress by 2.26%, achieving a coordinated improvement of both sealing performance and structural safety. Full article

This study investigates the design, microstructure, and performance profile of a novel composite coating combining a high-entropy alloy (HEA) matrix with cermet reinforcement. A 50wt.%CoCrFeMnNi_0.8V–50wt.% Cr₃C₂-Ni₈₀Cr₂₀ powder mixture was successfully deposited onto steel substrates via high-velocity oxy-fuel (HVOF) thermal spraying. Microstructural analysis revealed a highly dense, well-bonded coating architecture (450–500 μm thick) where partially melted, spherical HEA splats were uniformly surrounded by the Cr₃C₂-Ni₈₀Cr₂₀ phase. X-ray diffraction confirmed a complex multiphase evolution consisting of FCC, BCC, and σ-NiCr phases driven by the rapid solidification inherent to the HVOF process. Tribological evaluations via ball-on-disc testing demonstrated that incorporating the Cr₃C₂-Ni₈₀Cr₂₀ reinforcement significantly improves wear resistance compared to the monolithic HEA coating. The composite’s wear behavior is governed by a synergistic mechanism: the ductile HEA matrix accommodates plastic deformation, while the harder carbide particles enhance load-bearing capacity, transitioning from adhesive wear to mild third-body abrasion and protective tribo-oxidation. Conversely, electrochemical testing in a 3.5 wt.% NaCl solution showed that the composite coating exhibits higher corrosion current densities (10.53 × 10⁻⁶ A/cm²) and more active corrosion potentials than the pure HEA matrix. This behavior is attributed to localized micro-galvanic cells forming at the heterogeneous interfaces between the different phases, alongside chloride-induced destabilization of the surface oxide film. Overall, the novel composite coating offers a compelling, sustainable alternative for surface engineering applications requiring a balanced trade-off between mechanical toughness and acceptable environmental durability. This behavior is also verified by the comparison with previous results dealing with monolithic CoCrFeMnNi_0.8V and 75wt.%CoCrFeMnNi_0.8V–25wt.% Cr₃C₂-Ni₈₀Cr₂₀ thermal sprayed coatings, where it is evident that the increase of the reinforcing phase leads to an optimum combination of properties. Full article

High-Early-Strength Concrete (HESC) is increasingly required in accelerated construction, yet most existing studies focus on single nano-additives rather than hybrid waste-derived systems. This study investigates the individual and combined effects of nanoclay (NC), nanosilica (NS), and cellulose nanofibers (NCel)—each produced from industrial or agricultural waste—on the mechanical and microstructural properties of HESC. A Box–Behnken response surface methodology (RSM) design was employed to optimize nanomaterial dosages with respect to early-age compressive strength, while microstructural evaluation (SEM, EDS, elemental mapping) clarified the mechanisms of enhancement. The results demonstrate that NC, NS, and NCel play complementary roles in hydration acceleration, particle packing, pore refinement, and crack-bridging. The optimized hybrid system (1.64% NC, 0.115% NS, 0.027% NCel) achieved a 3-day compressive strength of 59.7 MPa, 7-day strength of 71.2 MPa, and 28-day strength of 94.6 MPa, representing increases of 42.14%, 36.92%, and 21.59%, respectively, over the control mixture. Microstructural observations confirmed matrix densification, reduced Ca/Si ratio (from 2.05 to 1.68), refined pore structure (<0.4 μm vs. 0.9–1.2 μm in control), and enhanced ITZ in the optimized mixtures. Statistical analysis yielded robust predictive models (R² = 0.977–0.996) with significant interaction terms confirming synergistic effects among the three nanomaterials. This work demonstrates that waste-derived hybrid nano-systems offer a sustainable and effective strategy for producing high-performance HESC, with the RSM-derived optimum providing balanced early- and later-age strength while maintaining practical feasibility for field implementation. Full article

In order to promote the sustainable development of road engineering, this study used waste tire rubber powder (RP) and surface organic layered double hydroxide (SOM-LDHs) to modify 70# matrix asphalt. The Box–Behnken design response surface method with three factors (rubber powder content, surface organic layered double hydroxide content, shear temperature) and three responses (penetration, ductility, softening point) was used to optimize the preparation parameters. The optimum formula was determined to be 21.7% rubber powder content, 4.8% surface organic layered double hydroxide content, and 160 °C shear temperature. The effect of the modifier on the surface morphology was analyzed using a rotating film oven test and ultraviolet aging test. The high and low temperature rheological properties of asphalt were evaluated by dynamic shear rheometer (DSR), bending beam rheometer (BBR), and the multi-stress creep recovery test (MSCR). The microstructure was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The aging mechanism was investigated by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The results show that after aging, the complex shear modulus of rubber powder/surface organic layered double hydroxide composite modified asphalt is the highest, which is 27.35% higher than that of matrix asphalt. The rutting factor reaches 79.86 kPa at 46 °C, the phase angle decreases by 11.83% after UV aging, and the high temperature plastic deformation resistance is the best. In the low temperature range of −18 °C to −24 °C, the creep stiffness of the composite modified asphalt is about 30% lower than that of the matrix asphalt, while the m value is increased by about 15%, and the low temperature stress relaxation performance is significantly improved. The strain recovery rate of composite modified asphalt under 3.2 kPa stress reaches 78.5%, and the unrecoverable creep compliance is as low as 0.18 kPa⁻¹, which is better than that of matrix asphalt and single rubber powder modified asphalt. Full article

This study evaluates the mechanical and durability performance of mortar incorporating paint sludge ash (PSA) as a partial replacement for ordinary Portland cement (OPC), with emphasis on predictive modeling and multi-response optimization using response surface regression techniques. PSA was produced through controlled calcination of industrial paint sludge and characterized by a high content of pozzolanic oxides (SiO₂ + Al₂O₃ + Fe₂O₃ > 70%), indicating pozzolanic potential. Its contribution to mortar performance is attributed to filler effects and pozzolanic reactions. Experimental dataset covering PSA contents (0–20%) and curing age (3–91 days) using Design-Expert software to evaluate their combined effects on compressive strength, ultrasonic pulse velocity (UPV), bulk density, water absorption, porosity, and sulfate resistance. The developed models demonstrated good predictive capability, with coefficients of determination (R²) ranging from 0.9073 to 0.9777, although significant lack-of-fit was observed for some responses, suggesting localized deviations that were not fully captured by the global polynomial models. Model adequacy was supported by ANOVA results, close agreement between adjusted and predicted R² values, low coefficients of variation (<10%), high adequate precision values (>4), and satisfactory residual diagnostic analyses. Results indicate that curing age enhances the measured performance parameters due to continued hydration and pozzolanic reactions, while PSA content exhibits a nonlinear effect governed by competing mechanisms. At moderate replacement levels (≈10–11%), through densified matrix and pore refinement, higher replacement levels reduce performance due to dilution of cementitious phases and slower reaction kinetics. Desirability-based multi-response optimization predicted an optimum PSA replacement level of approximately 10.57%, corresponding to a predicted compressive strength of 39.78 MPa at 91 days with prediction errors below 5%. Durability indicators were also improved within this range. Overall, PSA is demonstrated to be a viable supplementary cementitious material for sustainable mortar production. Full article

Background/Objectives: Despite available treatment options, glaucoma continues to be a leading cause of irreversible blindness. Current medications have multiple limitations, including rapid drainage, ocular irritation, requirement for multiple daily dosings, and systemic side effects. The current study was designed to engineer and characterize a pregabalin-containing enhanced delivery formulation (PRG-EDF) to directly address these inadequacies. Methods: PRG-EDF eye drops were prepared using ingredients that are either U.S. Food and Drug Administration (FDA)-approved for ophthalmic use or have established safety profiles. The formulation was characterized using multiple evaluations, including pH, zetasizer analyses, viscosity, in vitro drug release, transcorneal permeability, determination of dose concentration and volume, systemic exposure, and potential for tachyphylaxis. Efficacy was evaluated using both Dutch belted rabbits and baboons. Results: PRG-EDF provides extended release for up to 24 h. Ex vivo data reveal that PRG-EDF does not alter the inherent high PRG corneal permeability. An intraocular pressure (IOP) study using DB rabbits demonstrates that 40 µL of PRG-EDF, 0.6%, is the optimum dose of our formulation. Comparison of the efficacy of PRG-EDF with commercial products demonstrated its superiority in overall IOP-lowering efficacy. An extended in vivo assessment demonstrated that the potency of PRG-EDF reached maximum IOP-lowering amplitude after 4 weeks of daily dosing. Moreover, an in vivo bioadhesion assay demonstrated that EDF remained on the ocular surface for up to 24 h. Impressively, PRG-EDF is as effective in baboons as in rabbits. Conclusions: We have successfully engineered a highly promising once-daily glaucoma medication with superior efficacy, as illustrated by higher IOP-lowering ability and prolonged duration of action. Full article

To address the labor intensity and potential vegetative damage associated with mechanical picking of Osmanthus fragrans at full bloom, this study proposed a selective separation mechanism using a flexible roller-brush. Biomechanical measurements established a quasi-static operational window, with floral detachment requiring up to 1.2 N and petiole–branch retention remaining above 5.0 N during the observed period. Rigid–flexible coupled transient simulations provided mechanistic support for a flexible unloading effect, predicting approximately 1.3 N at the floral junction and approximately 2.5 N at the petiole–branch junction under the simplified model assumptions. A CZD-01 picker with a three-degree-of-freedom contour-following arm was developed, and a mixed I-Optimal response-surface design was used to identify a candidate-set optimum within the tested three-level factor domain. Bristle configuration was the strongest tested factor affecting immediate leaf detachment (p < 0.0001). Under the selected configuration of 161 r/min roller-brush speed, 8 r/min circumferential speed, and smooth PU bristles, ten validation trials in a flat standardized plantation yielded a flower-picking rate of 84.0 ± 1.38% and an immediate leaf detachment rate of 6.5 ± 0.61%. These results demonstrate promising selective-picking performance under the tested conditions; transferability to other cultivars, seasons, terrains, and long-term tree responses remains to be established. Full article

The development of highly crystalline tungsten oxide nanomaterials remains challenging for catalytic applications due to the difficulty in achieving high phase purity without sacrificing metal oxide loading. This work addresses this limitation through an innovative fast hydrothermal synthesis at 100 °C for 4 h without autoclaves or surfactants, using citric acid as a critical structural directing agent. Such methodology reduces the synthesis time by 50–80% compared to existing hydrothermal routes. Citric acid was identified as the critical parameter controlling the nanosheet thickness (20 nm to 35 nm) and diameter (109 nm to 173 nm), acting as a coordinating ligand. The resulting nanosheets were used to prepare Pt/WO₃/Al₂O₃ catalysts with well-defined crystalline monoclinic WO₃ structures at 9.5% wt. loading. Normally, this phase is inaccessible by standard impregnation at equivalent loading. NH₃-TPD characterization confirmed that crystalline WO₃ generates strong acid sites absent in the reference wet impregnation catalyst. Glycerol hydrogenolysis tests revealed that the presence of monoclinic WO₃ reduces the average glycerol conversion rate by a factor of 3.8 and systematically shifts selectivity toward over-hydrogenolysis products (1-propanol and 2-propanol), despite identical WO₃ loading and surface densities below the literature optimum of 2.2 W atoms ${\mathrm{nm}}^{-2}$. These results demonstrate that the WO₃ crystalline phase is a primary determinant of catalytic performance, without taking into account increased loading. Such demonstration will be useful for the rational design of selective glycerol hydrogenolysis catalysts. Full article