Search Results (514)

The objective of this study is to mitigate the bottom-out failure and improve the energy absorption of conventional helmet liners during high-energy impacts, thereby reducing the risk of head injuries. To this end, a locally reinforced Primitive-type triply periodic minimal surface (P-TPMS) energy-absorbing liner is proposed for the helmet forehead region, which facilitates progressive energy dissipation through layer-by-layer buckling deformation. A finite element model of a helmet–head coupling was created based on a previously verified high-fidelity head model and subsequently validated against the ECE 22.06 standard drop-test methodology. Three critical design parameters—outer protective layer thickness, triply periodic minimal surface (TPMS) unit cell size, and wall thickness—were optimized employing the Box–Behnken Design (BBD) response surface methodology, resulting in quadratic regression models for the head injury criteria (HIC) and peak linear acceleration (PLA) with good fit ($R^2$ > 0.97). Optimal parameter combinations were established using multi-objective optimization, with protective efficacy carefully assessed from both head dynamic response and biomechanical response perspectives. The ideal P-TPMS liner possesses an outer protective layer thickness of 14.95 mm, a TPMS unit cell size of 12.23 mm, and a wall thickness of 3.93 mm. Compared to the traditional expanded polystyrene (EPS) liner, the optimized P-TPMS liner significantly reduces HIC (by ∼16%) and PLA (by ∼14%) while extending the impact duration. More critically, it transitions both intracranial pressure and brain tissue strain below their respective clinical injury thresholds, substantially lowering the risks of skull fracture and mild traumatic brain injury (mTBI). The P-TPMS construction facilitates continuous energy dissipation during impacts via incremental layer-by-layer buckling deformation, hence extending impact duration and markedly improving helmet protective efficacy. These findings offer theoretical foundations and technical direction for the creation of localized heterogeneous liner designs in advanced high-performance helmets, although the results are limited to frontal flat-anvil impact conditions. Full article

Subcritical water extraction (SWE) is an eco-friendly and efficient technique for isolating bioactive ingredients from natural products. To improve the extraction yield of Artemisia argyi leaf polysaccharides (AAPs), a three-stage hybrid optimization strategy combining single-factor experiments, response surface methodology (RSM), neural network (NN), and direct search algorithm (DSA) was proposed. Single-factor experiments were used to screen key parameters. A Box–Behnken design (BBD)-based RSM was applied for preliminary optimization. A {3, 5, 1} structured NN was trained using 63 datasets from RSM, and DSA was used to determine the globally optimal process parameters. The optimal conditions were obtained as follows: extraction time 17.72 min, liquid-to-solid ratio 92.83 mL/g, extraction temperature 123.35 °C, stirring speed 1800 r/min, and natural pH. Under these conditions, the experimental AAP extraction yield reached 6.99%, with a relative error of only 1.16% compared with the predicted value of 6.91%. Fourier transform infrared (FT-IR) spectroscopy confirmed that the product exhibited typical polysaccharide structural characteristics. The integrated RSM–NN–DSA framework provides a reliable and high-precision approach for optimizing SWE of plant polysaccharides, showing good potential for industrial applications. Full article

High-pressure liquid CO₂ jets possess the characteristics of low-temperature cooling and dry, residue-free impact, which makes this technology particularly suitable for removing hydroxyl-terminated polybutadiene (HTPB) propellant from decommissioned solid rocket motors. However, existing studies lack multi-objective optimization of impact efficiency and CO₂ consumption, which limits their engineering applications and further promotion. In this study, a high-accuracy quadratic Response Surface Methodology (RSM) relating process parameters to damaged volume was established using a Box–Behnken design (BBD) combined with three-dimensional topography scanning. A theoretical model for CO₂ consumption was developed based on the Homogeneous Equilibrium Model (HEM). On this basis, the Non-dominated Sorting Genetic Algorithm II (NSGA-II) was used to obtain the Pareto-optimal set for maximizing propellant damaged volume and minimizing CO₂ consumption. The results indicate that nozzle diameter has the most significant effect on damaged volume and exhibits a strong interaction with jet pressure. The knee-point solution gives a jet pressure of 15.35 MPa, a stand-off distance of 5 mm, and a nozzle diameter of 1.8 mm. Compared with the initial condition, this compromise condition increases the damaged volume by 72% while increasing CO₂ consumption by only 4.9%. Furthermore, the temperature in the impact zone was reduced to a minimum of −92.4 °C, with no thermal accumulation observed. These findings reveal the influence of liquid CO₂ jet process parameters on impact efficiency and CO₂ consumption, providing a theoretical basis and parameter references for its engineering application in the safe removal of propellants from decommissioned solid rocket motors. Full article

Objective: Perillae Fructus (PF) (Perilla frutescens (L.) Britt.) and stir-fried Perillae Fructus (SFPF) are commonly used clinically for the treatment of cough and asthma, yet their quality control methods have not been fully established. Method: The best processing techniques of PF were optimized by one-variable-at-a-time (OVAT) analysis and Box–Behnken design (BBD); fingerprint combined with chemical pattern recognition techniques was employed to establish chromatographic fingerprints of PF and SFPF from different regions. Differential compounds were screened and the reliability of the established method was verified through quantitative analysis of multi-components; image processing technology was applied to determine chromaticity values and perform cluster heatmap analysis. The composition–color correlation of PF and SFPF was investigated. Result: Four characteristic components were identified through 36 batches of PF and SFPF, with rosmarinic acid, 5-hydroxymethylfurfural, caffeic acid and luteolin serving as discriminant markers differentiating PF and SFPF. The contents of seven components and the corresponding chromaticity parameters (L*, a*, b*) were determined to generate a visualized heatmap. Rosmarinic acid and caffeic acid showed positive correlations with L*, whereas a negative correlation was shown with b* and 5-hydroxymethylfurfural. Conclusions: This study provides a theoretical basis for judgment of processing endpoints and the rapid online quality monitoring of SFPF. Full article

In many industrial applications, the significant differences in flow rates and physical properties between the hot and cold media of plate heat exchangers (PHEs) often lead to differentiated performance requirements. Asymmetric structural design is an effective approach to addressing these specific needs. In this paper, a novel fish-scale corrugated asymmetric plate heat exchanger (APHE) was designed and multi-objective optimization was performed based on the objectives of minimizing the water side pressure drop, ΔP, and maximizing the overall heat transfer coefficient, K. Numerical simulations of the fish-scale corrugated APHE were conducted with the Box–Behnken Design (BBD) in the Response Surface Methodology (RSM). The corrugation angle, corrugation pitch, and protrusion ratio were selected as geometric variables. Through Analysis of Variance (ANOVA), significant regression models were established for the two competing performance indicators. Subsequently, Pareto optimal solutions were identified using the fast and elitist non-dominated sorting genetic algorithm (NSGA-II). A comparison of the performances reveals that the novel APHE reduces ΔP by 47.13% and increases K by 5.77% compared to the original chevron-type PHE. Further analysis of the simulation data reveals that the convective heat transfer coefficient on the refrigerant side is increased by 24.06%. These findings substantiate the benefits of the asymmetric feature of the fish-scale protrusion and offer a comprehensive and effective design strategy for APHEs. Full article

Bitter Melon Leaf Extract (BMLE) possesses potential anticancer and anti-inflammatory properties; however, conventional extraction methods restrict phytochemical yield and bioactivity. Here, we optimized extraction using High-Pressure Processing (HPP) with Box–Behnken Design (BBD) and Response Surface Methodology (RSM). The optimized extract (O-BMLE) demonstrated significantly higher total flavonoid content (27.7 vs. 8.7 mg RE/g) and FRAP antioxidant capacity (96.5 vs. 71.2 μmol TE/g) compared to conventional BMLE. Additionally, O-BMLE exhibited enhanced cytotoxicity (A549 IC₅₀: 58.7 vs. 147 μg/mL) and selectivity (SI: 5.03 vs. 2.60) against A549, HepG2, and SKOV3 cancer cells while showing minimal effects on 3T3-L1 fibroblasts. In LPS-stimulated RAW264.7 macrophages, O-BMLE selectively inhibited JNK phosphorylation without affecting NF-κB phosphorylation, resulting in suppression of iNOS, COX-2, IL-1β, IL-6, and TNF-α expression as well as nitric oxide production. HPLC analysis revealed equivalent momordicine-I levels (~28 mg/g) between extracts. In contrast, HPLC-qTOF-MS profiling revealed that O-BMLE was enriched in stearidonic acid (66% increase in relative abundance), 4-hydroxybenzoic acid (19.5%), monolinolenin, 6-gingerol, and pedunculoside, which are compounds linked to JNK inhibition, antioxidant activity, and cytokine suppression. These results indicate that HPP-BBD/RSM optimization selectively modifies the bitter melon leaf metabolome, thereby enhancing anticancer and anti-inflammatory activities independently of momordicine-I content alone. O-BMLE may therefore serve as a promising candidate for the development of functional foods and nutraceuticals targeting inflammation-associated cancers. Full article

Pipeline intelligent plugging robots (PIPRs) are used for in-line isolation and emergency repair of oil and gas pipelines. During anchoring, slip teeth contact the inner pipe wall. This contact causes stress concentration, microslip, and local wear. Pipe wall wear may reduce pipeline service life and plugging reliability. This study proposes a wear-response-based optimization method for slip structure design. A simplified slip–pipe contact model was established. Wear depth was selected as the main response. Five slip structural parameters were used as design variables. The Box–Behnken Design (BBD) model was constructed to describe the relationship between structural parameters and wear depth. The Ant Lion Optimizer (ALO) model was introduced to search for the minimum-wear parameter combination. Contact stress and local deformation were used as auxiliary indicators for structural safety evaluation. Experimental tests were conducted to verify the simulation and optimization results. Strain-derived stress and wear scar morphology were compared with the numerical results. The results show that the optimized structure reduces the minimum wear depth to 0.045 mm. The experimental results agree with the simulation trend. This indicates that the proposed method can reduce pipe wall wear while maintaining anchoring reliability. The BBD–ALO framework provides a general optimization method for contact structures with wear constraints. This method can be applied to anchoring, gripping, and support structures in pipeline robots and other mechanical systems. Full article

To address underground shotcrete support scenarios with potential radiation-protection requirements, a bismuth oxide/clay functional filler was incorporated into a baseline shotcrete formulation. Functional filler dosage, calcium formate dosage, and PCE dosage were selected as variables, and Box–Behnken response surface methodology was used to establish quadratic regression models for 28 d compressive strength, fluidity, and bond strength. Representative optimized mixtures were further evaluated by MCNP5 simulation, gamma-ray air-kerma attenuation tests, and SEM. The models showed good fitting and predictive performance within the investigated design space. Functional filler dosage mainly controlled compressive strength and bond strength, whereas PCE dosage dominated fluidity. Under the constraints of compressive strength ≥ 25 MPa, fluidity of 160–170 mm, and bond strength ≥ 0.8 MPa, three representative mixtures were selected for shielding-, strength-, and interface-priority strategies. Simulated and measured results showed consistent shielding-performance rankings, and the optimized mixtures exhibited higher gamma-ray attenuation than the blank mixture. BBD26 achieved the highest shielding performance, with measured shielding rates of 65.51% and 51.54% at 661.7 keV and 1.25 MeV, respectively. Thickness-gradient tests indicated exponential attenuation, while SEM revealed differences in Bi-bearing particle distribution and matrix continuity. Full article

Fisheries wastewater contains high levels of suspended solids and organic matter, posing significant environmental risks and necessitating effective and sustainable treatment approaches. This study aims to determine the characteristics of the neem (Azadirachta indica) leaf biocoagulant, assess the interactions among research variables, and optimize its use to reduce total suspended solids (TSS) and chemical oxygen demand (COD) levels in fisheries wastewater. The method used is response surface methodology (RSM), specifically the Box–Behnken Design (BBD), which involves three variables (biocoagulant concentration, fast stirring speed, and sedimentation time) and two responses (TSS and COD removal). Characterization results (Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and zeta potential) indicated that the biocoagulant contains functional groups such as hydroxyl, carboxyl, and amine, contributing to coagulation–flocculation through adsorption and polymer bridging mechanisms. Statistical analysis confirmed that the developed quadratic models were significant (p-value < 0.05), with high F-values, non-significant lack of fit, and strong coefficients of determination (R² = 0.9111 for TSS and 0.9419 for COD), along with low coefficients of variation (CV < 5%), indicating good model reliability. Although the model generally has a significant effect on the response, the fast stirring speed does not, while the other two factors do. The optimal conditions (based on desirability) were determined to be a biocoagulant concentration of 79.8 mg/L, a fast stirring speed of 100 rpm, and a sedimentation time of 27.5 min. Under these conditions, TSS and COD removals of 88.72% and 79.98%, respectively, were achieved. These findings demonstrate the potential of neem leaf biocoagulant as a sustainable, environmentally friendly alternative to conventional chemical coagulation, supporting cleaner production in aquaculture systems. Full article

(1) Background: Flavored craft beer is favored for its diverse and distinctive aroma compounds; however, traditional fermentation processes are often plagued by poor yeast flocculation, which leads to substantial beer losses and compromised production efficiency. Yeast immobilization technology has emerged as a promising strategy to improve fermentation performance, shorten the primary fermentation period, and mitigate beer loss. (2) Methods: In this study, a natural material–based carrier was developed for the immobilization of yeast, and its application in mango craft beer fermentation was systematically investigated. The optimal fermentation conditions were screened, and the physicochemical properties, nutritional composition, and volatile flavor profiles of the resulting mango craft beer were comprehensively evaluated. (3) Results: The results showed that the maximum mass gain of yeast after immobilization on the natural carrier reached 13.3%. Compared with free yeast, the immobilized yeast exhibited a 1.58-fold higher average extract consumption rate and a 1.39-fold higher alcohol production rate based on the overall fermentation system, while the primary fermentation period was shortened by approximately 33%. Under the optimized fermentation conditions, the mango craft beer achieved a sensory score of 81 points, with a β-carotene retention rate of 91.25%. Furthermore, the mango craft beer exhibited a more diverse profile of volatile flavor compounds and enhanced nutritional composition compared with the control. (4) Conclusions: Overall, fermentation conditions were optimized using Response Surface Methodology (RSM) based on Box–Behnken Design (BBD). Natural immobilization carrier developed in this study effectively enhanced yeast fermentation efficiency and shortened the primary fermentation cycle, and these findings demonstrate its significant potential for cost reduction and efficiency enhancement in the production of flavored craft beer, providing a practical technical support for the industrial application of natural carrier-based yeast immobilization technology. Full article

In this study, the Box–Behnken Design (BBD) was adopted to optimize the ultrasound-assisted extraction (UAE) conditions of polyphenols from Hericium erinaceus (H. erinaceus) on the basis of single-factor experiments, with extraction time, solid–liquid ratio and ethanol concentration as the key investigation factors. The optimal extraction parameters were determined as follows: extraction time of 56.85 min, solid–liquid ratio of 1:56.71 g/mL and ethanol concentration of 44.64%, under which the actual yield of the total polyphenol crude extract (TPCE) reached 0.9985 ± 0.03%, which was highly consistent with the theoretical predicted value of 0.9960%, verifying the good fitting degree of the established model. Taking L-ascorbic acid as the positive control, the antioxidant activity of TPCE was evaluated by determining its scavenging capacity against ABTS·⁺, ·OH and DPPH· free radicals, and the half-maximal effective concentration (EC₅₀) values were measured to be 0.8850, 0.9490 and 4.198 mg/mL, respectively. With acarbose as the reference drug, the inhibitory effects of TPCE on α-amylase and α-glucosidase related to carbohydrate metabolism were assayed, and the corresponding half-maximal inhibitory concentration (IC₅₀) values were 0.0135 and 130.3 mg/mL, respectively. Furthermore, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) was employed for the tentative identification of bioactive components in TPCE, and a total of 48 and 64 chemical constituents were characterized in negative and positive ion modes, respectively, providing a chemical basis for the biological activities of TPCE. This study confirmed that UAE is an efficient and feasible technology for extracting polyphenols from H. erinaceus, which lays a theoretical foundation for the development and utilization of its polyphenols, and also provides novel insights into the development of natural functional ingredients and potential therapeutic agents for the intervention of type 2 diabetes. Additionally, the findings further validate edible fungi as a valuable reservoir of natural bioactive substances, with promising application prospects in the research and development of functional foods and pharmaceuticals targeting metabolic diseases. Full article

Background: The increasing antimicrobial resistance has led to a greater demand for alternative treatment options, which in turn has increased interest in naturally occurring biomolecules such as pyocyanin. Methods: In this study, a three-factor Box–Behnken Design (BBD)-based response surface methodology (RSM) was employed to optimize the effects of glycerol, peptone, and pH on pyocyanin production by Pseudomonas aeruginosa OG1. The antimicrobial efficacy of the optimized pyocyanin was subsequently evaluated in vitro against three Candida species and four clinically important bacterial pathogens using the disk diffusion method, with gentamicin and fluconazole used as positive controls. Results: The second-order polynomial model demonstrated excellent fit (F = 176.3, p < 0.0001) with a non-significant lack of fit, indicating adequate representation of the experimental data. The optimal conditions were determined to be glycerol at 1.11% (w/v), peptone at 17.86 g/L, and a pH of 7.27, yielding a predicted pyocyanin concentration of 25.92 mg/L. Antimicrobial testing revealed broad-spectrum, dose-dependent activity against all tested microorganisms. The highest efficacy was observed against Bacillus cereus (26.4 ± 1.3 mm at 40 µg/mL), followed by Candida glabrata (21.5 ± 1.6 mm), Klebsiella pneumoniae (17.6 ± 1.4 mm), Candida albicans (15.4 ± 1.8 mm), Candida parapsilosis (13.2 ± 1.9 mm), Proteus mirabilis (12.5 ± 1.3 mm), and MRSA Staphylococcus aureus (9.2 ± 1.1 mm). Conclusions: These findings demonstrate that BBD-based RSM is a robust approach for optimizing pyocyanin production and that pyocyanin represents a promising dose-dependent antimicrobial agent against susceptible pathogens. Full article

Field breeding trial-plot harvesting is one of the key processes in crop breeding, as any mixing between varieties during harvest directly leads to the invalidation of breeding data. Therefore, achieving zero-residue self-cleaning inside the machine during harvesting is essential. Existing studies have largely relied on simulations to optimize cleaning parameters. However, research specifically targeting the synergistic design of the mechanical and pneumatic components of the cleaning device to achieve efficient and thorough self-cleaning in complex real-world conditions remains lacking. To address this issue, this paper presents a novel cleaning system specifically designed for efficient self-cleaning and optimizes its key parameters. Key structural parameters of the straw walker, vibrating sieve, and cleaning fan were analyzed, establishing preliminary ranges for crank speed, sieve-airflow angle, and fan speed. A test bench was developed, and single-factor experiments were conducted to investigate the effects of these parameters on core self-cleaning indicators, including the self-cleaning rate and self-cleaning time. The optimal parameter combination was obtained using the Box–Behnken design (BBD) response surface methodology: a crank speed of 390.80 r/min, a sieve-airflow angle of 29.88°, and a fan speed of 1995 r/min. Bench tests validated that the system achieved excellent cleaning performance while ensuring a self-cleaning rate of 100% and a reduced self-cleaning time of 20 s. The system’s effectiveness was further validated through field experiments using a 4LX1 prototype harvester on three wheat varieties. Results demonstrated zero grain mixing between plots, with self-cleaning times of 9–12 s. Both bench and field test results exceeded the relevant standards, effectively resolving the long-standing issue of grain residue in trial plot harvesting. Through dual validation, this study provides a referential solution for addressing grain residue and establishes a theoretical foundation for the synergistic design of efficient and precision breeding harvest technologies. Full article

The valorization of agro-industrial by-products is a sustainable approach to recovering high-value bioactive compounds. In this study, Opuntia ficus-indica (L.) Mill. seed press residues were investigated as a source of phenolic and flavonoid compounds using microwave-assisted extraction (MAE). A multi-step optimization strategy was implemented, combining preliminary single-factor experiments (OVAT), response surface methodology based on a Box–Behnken design (BBD), and machine learning modeling using K-nearest neighbors coupled with the dragonfly algorithm (KNN_DA), followed by desirability-based validation. The effects of ethanol concentration (50–100%), microwave power (400–800 W), extraction time (2–4 min), and liquid-to-solid ratio (30–50 mL/g) were evaluated on Folin–Ciocalteu reducing capacity (FCRC), AlCl₃ complexation response, and antioxidant activity assessed by DPPH radical scavenging and reducing power assays. Optimal conditions were identified at 50% ethanol, 800 W microwave power, 4 min extraction time, and a liquid-to-solid ratio of 47.28 mL/g. Under these conditions, FCRC reached 376.85 ± 0.23 mg GAE/100 g DW and 49.16 ± 0.33 mg QE/100 g DW for AlCl₃ complexation response, with prediction errors of 2.80% and 0.82%, respectively. The optimized extracts exhibited enhanced antioxidant activity. These findings confirm MAE as a rapid and environmentally friendly technique and highlight the predictive performance of the KNN_DA model for process optimization. Full article

In this study, phenolic hydroxyl-functionalized poly(α,β-[N-(2-hydroxyethyl)-D, L-aspartamide]) (PHEA-HP) was used to prepare hydrogel beads via an emulsion-enzymatic gelation process. The effects of the preparation conditions on the size and size distribution span of the hydrogel beads were investigated. Initially, single-factor experiments were conducted to determine the range of preparation conditions for hydrogel beads. Subsequently, a Box–Behnken design combined with response surface methodology (BBD–RSM) was employed to optimize the emulsification parameters for preparing hydrogel beads, with three numerical independent variables (oil-to-water ratio, homogenization rate, and Span 80 dosage) and two responses (size and size distribution span). The results indicated that the size distribution span fit the quadratic model well and was more sensitive to the three independent variables than size. The optimal preparation conditions were validated to be an oil-to-water ratio of 10.3, a homogenization rate of 2930 rpm, and a Span 80 dosage of 2.0%. At the optimum point, the prepared PHEA-HP hydrogel beads were spherical, with an average size of 14.0 ± 0.2 μm and a size distribution span of 0.185 ± 0.010. Full article