Search Results (1,622)

Prediction models for polymer injection molding quality often degrade due to shifts in operating conditions caused by variations in melting temperature, cooling efficiency, or machine conditions. To address this challenge, this study proposes a drift-aware dynamic quality-monitoring framework that integrates hybrid-feature autoencoder (HFAE) drift detection, sliding-window reconstruction error analysis, and a mixed-feature artificial neural network (ANN) for online quality prediction. First, shifts in processing parameters are rigorously quantified to uncover continuous drifts in both input and conditional output distributions. A HFAE monitors reconstruction errors within a sliding window to promptly detect anomalous deviations. Once the drift index exceeds a predefined threshold, the system automatically triggers a drift-event response, including the collection and labeling of a small batch of new samples. In benchmark tests, this adaptive scheme outperforms static models, achieving a 35.4% increase in overall accuracy. After two incremental updates, the root-mean-squared error decreases by 42.3% across different production intervals. The anomaly detection rate falls from 0.86 to 0.09, effectively narrowing the distribution gap between training and testing sets. By tightly coupling drift detection with online model adaptation, the proposed method not only maintains high-fidelity quality predictions under dynamically evolving injection molding conditions but also demonstrates practical relevance for large-scale industrial production, enabling reduced rework, improved process stability, and lower sampling frequency. Full article

Inspired by the concept of antennas in electromagnetics, this study proposes a novel acoustic metamaterial using Archimedean spiral structures. Unlike traditional resonant absorption structures, the present structure does not rely on resonant cavities but consists of multiple channels bent according to specific geometric parameters. The absorption mechanism is attributed to the combination of Fabry–Pérot (FP) resonance and viscous loss effects at waveguide boundaries. A theoretical model based on the transfer matrix method has been established and validated through numerical methods. Furthermore, the present study investigated the relationship between absorption performance and geometric parameters through theoretical analysis and numerical simulations, achieving efficient absorption across a wide frequency range and at low frequencies by adjusting these parameters. Additionally, samples have been fabricated using additive manufacturing techniques and experimental validation confirmed the accuracy of the theoretical and numerical simulations. The structure designed in this paper is expected to be applied to the engineering field with the need of broadband sound absorption. Full article

The increasing demand for safe and durable feed materials highlights the need for processing methods that simultaneously enhance physical quality and reduce microbiological contamination. Extrusion technology offers a promising solution by combining thermal and mechanical effects that improve binding performance while inactivating fungal spores present in cereal grains. In this study, maize, barley, sorghum, soybean, and wheat grains naturally contaminated with fungal spores were subjected to extrusion prior to pelleting. The physical properties of the resulting pellets, including bulk density, physical density, and kinetic durability, were evaluated and compared with those obtained from ground (non-extruded) grains. Pellets containing extruded grains generally exhibited higher physical density, with the highest value recorded for pellets containing extruded mould-infected sorghum grain (1179.82 kg·m⁻³) and the lowest for pellets containing healthy soybeans (1063.63 kg·m⁻³). The kinetic durability of extruded cereal pellets increased on average by 4.02%, enhancing their resistance to mechanical stress during transport and storage. Microbiological analyses confirmed a significant reduction in fungal colony-forming units (CFUs) after extrusion and pelleting, ranging from 27% to 65%, depending on the cereal type. The most pronounced reduction was observed in maize-based pellets contaminated with mould spores, decreasing from 1.70 × 10⁵ to 6.03 × 10⁴ CFU·g⁻¹. These results demonstrate that extrusion is an effective method for producing cereal-based feed materials with improved physical quality and enhanced microbiological safety, contributing to more sustainable feed production. Full article

Compared to traditional processes, fused deposition modeling 3D printing can manufacture parts of various shapes without the need for additional equipment, moulds, fixtures, or other tools. Its excellent characteristics have been widely applied in many industries. However, balancing product quality with low-carbon production has always been a pressing issue for 3D printing companies to address. To improve the stability of 3D printing in terms of part size accuracy and sustainable development, an orthogonal experimental design method, RSM-NSGA-II, and an entropy weight TOPSIS method were employed to optimise the factors affecting size accuracy and carbon emissions. The layer height, nozzle temperature, filling density, first layer height, and printing pattern were selected as factor variables, and the circular runout tolerance value and carbon emissions of printed parts were set as optimisation objectives. An L18 orthogonal experimental design was established. The influence of process parameters on quality indicators and the optimal combination of process parameters were analysed through range calculation. In addition, the NSGA-II-based optimisation model was constructed using the experimental design method in response surface methodology, and combined with the entropy weight TOPSIS method, to determine the optimal FDM 3D printing process parameter scheme with the best comprehensive performance. The results indicate that the response surface model established in this paper has good adaptability. When the layer height is 0.2 mm, the nozzle temperature is 243 °C, the filling density is 70%, and the first layer height is 0.15 mm, the circular runout tolerance value and carbon emissions are reduced by 64.29% and 53.45% respectively, compared to the original values. This study provides a theoretical basis and technical support for optimising the FDM manufacturing process in low-carbon and environmentally friendly production. Full article

This study aimed to determine the antifungal activity of various compounds and develop a novel antifungal formulation against fungal pathogens, including Alternaria alternata, Botrytis cinerea, Penicillium expansum, and Rhizopus stolonifer. A total of 32 plant-derived secondary metabolites and three extracts (dichloromethane, ethyl acetate, and methanol) from Lawsonia inermis, Juglans regia, and Drosera intermedia were screened at a concentration of 250 ppm. The chemical composition of the D. intermedia ethyl acetate extract was characterized using chromatographic techniques. Subsequently, an emulsifiable concentrate formulation from this extract was prepared, and its efficacy was evaluated at concentrations ranging from 250 to 2000 ppm. The D. intermedia ethyl acetate extract was found to contain three flavonoids (1.4%) and three naphthoquinones (2.8%). The formulation exhibited optimal effect at 1000 ppm. Overall, the high efficacy of the formulation containing the dried D. intermedia extract (10:1, ethyl acetate) positions it as a promising and viable alternative to synthetic fungicides. Full article

Reusing existing buildings is a valid response to the architectural challenge associated with addressing climate change and can aid the regeneration of the historic built environment. This demands sensitive architectural conservation strategies that improve thermal comfort, indoor environmental quality, and energy efficiency. In addition, energy retrofit solutions that balance performance improvements with the conservation of cultural and architectural values are needed to achieve higher performance while preserving cultural heritage, architectural features, and identity. Energy retrofits of post-war, mid-20th-century buildings pose particular challenges, including low ceiling heights, full-height windows, external decorative components, and other structural aspects, as these features hinder thermal upgrades. Concrete buildings from this period are frequently demolished due to limited guidance on effective retrofit methods. This study explores the most effective energy retrofit strategies for balancing energy efficiency with conservation requirements in such buildings, and assesses the risks associated with condensation and thermal bridging arising from internal insulation strategies. This paper examines internal insulation as a retrofit solution, where external insulation is not feasible. Internal wall insulation (IWI) reduces overall heat loss but concentrates thermal transfer at uninsulated junctions, thereby increasing the risk of condensation. In the simulated case, a relatively thin, short strip of slab insulation, combined with wall insulation, significantly reduced condensation and mould risk, suggesting a potential solution for mid-century building types. The analysis shows that applying insulation asymmetrically worsens conditions on the uninsulated side. Full-height window replacement, coupled with internal slab insulation, results in the most significant improvement; however, slab insulation alone can mitigate condensation risks where window replacement is not permitted. Findings highlight that partial insulation at balconies, parapets, and roof junctions is minimally effective, reinforcing the importance of integrated internal strategies for successful retrofits. Full article

Dry film photoresist (DFR) is a solid photosensitive resin film that enables multilayer lamination and rapid patterning at relatively low temperatures. Initially developed for the production of printed circuit boards (PCBs), DFR has demonstrated significant application value in the field of micromachining over the past few decades. This paper systematically introduces the structure and lithography mechanism of DFR, provides a broad classification of its applications in micromachining, and focuses on reviewing the latest progress of different applications, including microstructure creation, mould processing, and sacrificial mask fabrication. Furthermore, this article discusses the current challenges encountered by DFR in micromachining at this point, as well as the key areas that warrant further investigation in future research. Full article

The flow and solidification inside the mould are crucial to the quality of the casting billet during continuous casting. In this work, a three-dimensional coupled model of flow and solidification was established, and the flow field and temperature distribution characteristics of molten steel were deeply explored. The results indicated that the molten steel streams out of the SEN at a defined degree and enters the mould in the form of an impact stream, and then impacts the narrow surface. The eddy core position in the upper recirculation region of the flow field is (0.565 m, −0.179 m), and eddy core position in the lower recirculation region is (0.524 m, −0.455 m). Within the range of 100–400 mm from the liquid surface, the main stream and upper ring flow of molten steel have a significant impact on the solidification of the casting billet, and the distribution and longitudinal variation in the liquid phase ratio at different height sections are very obvious. At the exit of the mould, the average thickness of the inner arc and outer arc shells is 15.2 mm and 14.5 mm, respectively. The model can provide guidance for enhancing and optimizing the quality of continuous casting billets. Full article

Single-use plastic cups and packaging materials pose severe environmental challenges due to their persistent nature and harmful impact on ecosystems and wildlife. Simultaneously, the indiscriminate disposal and burning of agricultural and food processing biomass contribute significantly to pollution. Among this biomass, waste generated from corn and fruit processing is produced in substantial quantities and is rich in natural fibres, making it a potential source for developing biodegradable products. This study focuses on the development of biodegradable cups using corn cob powder, mango peel powder, and pineapple peel powder through hot-press compression and moulding technology. The formulation was optimized using response surface methodology, with independent variables, i.e., corn cob (20–40 g), mango peel (30–50 g), and pineapple peel (20–30 g). The responses evaluated including hardness, colour (L* value), and water-holding capacity. The model was fitted using a second-order polynomial equation. Optimum results were achieved with 34 g of corn cob, 40 g of mango peel, and 26 g of pineapple peel powder, yielding a maximum hardness of 2.41 kg, an L* value of 47.03, and a water-holding capacity of 18.25 min. The optimized samples further underwent characterization of physical properties, functional groups, lattice structure, surface morphology, and biodegradability. Colour parameters were recorded as L* = 47.03 ± 0.021, a* = 10.47 ± 0.041, and b* = 24.77 ± 0.032. Textural study revealed a hardness of 2.411 ± 0.063 and a fracturability of 2.635 ± 0.033. The developed biodegradable cup had a semicrystalline nature with a crystallinity index of 44.4%. Soil burial tests confirmed that the developed cups degraded completely within 30 days. These findings highlight the potential of corn and fruit processing waste for developing eco-friendly, biodegradable cups as sustainable alternatives to single-use plastics. Full article

Dy@C₈₂ is one of the metallofullerenes studied as dopants for improvements of stability and performance of solar cells. Calculations should help in formulating rules for selections of fullerene endohedrals for such new applications in photovoltaics. Structure, energetics, and relative equilibrium populations of two potential-energy-lowest IPR (isolated pentagon rule) isomers of Dy@C₈₂ under high synthetic temperatures are calculated using the Gibbs energy based on molecular characteristics at the B3LYP/6-31G*∼SDD level. Dy@$C_{2v}\left(9\right)$-C₈₂ and Dy@$C_s\left(6\right)$-C₈₂ are calculated as 58 and 42%, respectively, of their equilibrium mixture at a synthetic temperature of 1000 K, in agreement with observations. The Dy@$C_{2v}\left(9\right)$-C₈₂ species is found as lower in the potential energy by 1.77 kcal/mol compared to the Dy@$C_s\left(6\right)$-C₈₂ isomer. Full article

In this study, aiming to develop novel biocomposites that offer competitive properties while retaining their renewable and biodegradable characteristics, a biodegradable polymer matrix (Mater-Bi^® HF51L2) was reinforced with natural particles extracted from the culm and leaf of Cymbopogon flexuosus (lemongrass). Particles (<500 µm) were incorporated at 10 and 20 wt.% via twin-screw extrusion followed by compression moulding. Morphological analysis via SEM revealed distinct structural differences between culm- and leaf-derived particles, with the latter exhibiting smoother surfaces, higher density, and better dispersion in the matrix, resulting in lower void content. Quasi-static mechanical tests showed increased stiffness with filler content, particularly for leaf-based composites. This material, at 20 wt.% filler loadings, enhanced the tensile and flexural moduli of the neat Mater-Bi approximately three and two times, respectively, a result attributed to enhanced interfacial adhesion. Rheological measurements (rotational and capillary) indicated significant increases in complex viscosity, particularly for leaf-filled systems, confirming restricted polymer chain mobility and good matrix–filler interaction. Dynamic mechanical thermal tests (DMTA) results showed an increased storage modulus and a shift in glass transition temperature (T_g) for all biocomposites in comparison to Mater-Bi matrix. Specifically, the neat matrix had a T_g of −28 °C, which increased to −24 °C and −18 °C for the 20 wt.% culm-reinforced and leaf-reinforced biocomposites, respectively. Overall, the leaf-derived particles demonstrated superior reinforcing potential, effectively improving the mechanical, rheological, and thermal properties of Mater-Bi-based biocomposites. Full article

Trichoderma aggressivum f. aggressivum is a major pathogen responsible for the green mould disease in Agaricus bisporus, causing significant yield losses. This study evaluated the effects of native bacterial strains as biocontrol agents against T. aggressivum f. aggressivum in the cultivation of Agaricus bisporus. Bacterial strains were collected from mushroom caps and screened for plant growth-promoting traits, including siderophore production, phosphate solubilisation, indole-3-acetic acid synthesis, chitinolytic, and proteolytic activities. In vitro antagonism assays identified Pseudomonas chlororaphis (Pl 4/2), Bacillus wiedmannii (Pl 6/1), and Bacillus cereus (Pl 5/2) as the most promising candidates. In vivo assays under controlled compost conditions revealed that Pl 5/2 significantly enhanced mycelial growth in A. bisporus. Field trials have confirmed its strong biocontrol potential, with disease severity reductions comparable to the fungicide Prochloraz. Furthermore, Pl 5/2 markedly increased the mushroom yield and the improved cap number and weight in A. bisporus. These results demonstrate the dual functionality of B. cereus Pl 5/2 in suppressing green mould and promoting yield, supporting its potential integration into sustainable, chemical-free mushroom production systems. Full article

Ten phyllospheric yeast strains were studied for their potential as biocontrol agents against fruit spoilage mould. The efficacy of these yeasts against Botrytis cinerea and Fusarium fujikuroi was assessed using dual-culture, mouth-to-mouth, radial growth inhibition and post-harvest fruit assays. Additionally, their capacity for producing hydrolytic enzymes was examined. Results from the ten yeasts revealed dual culture antagonism ranging from 41% to 63% against B. cinerea and 23% to 48% against F. fujikuroi, along with radial inhibition ranging from 70% to 100% and 47% to 100%, respectively. Additionally, in vitro inhibition through the production of volatile organic compounds (VOCs) varied from 2% to 46% against B. cinerea and 6% to 64% against F. fujikuroi. Overall, Aureobasidium melanogenum J7, Suhomyces pyralidae Y1117, Dekkera anomala V38, and Rhodotorula diarenensis J43 emerged as the best-performing biocontrol yeasts. Volatile organic compounds produced by the four yeasts were also identified and included in fruit bioassays using pears and tomatoes. Various VOCs, including 1-butanol, 3-methylbutanol, and butyric acid, were linked to the antagonistic properties of the selected yeasts. Lastly, the four chosen yeast strains significantly mitigated post-harvest spoilage caused by B. cinerea and F. fujikuroi in pear and tomato fruits, with D. anomala V38 exhibiting the greatest inhibitory activity. These findings underscore a potential sustainable and efficient approach to reducing mould-induced post-harvest spoilage while reducing reliance on synthetic fungicides. Full article

Plant secondary metabolites are an interesting source of natural antifungals and offer an alternative to synthetic preservatives. In this study, the activity of 218 secondary metabolites was evaluated against nine Penicillium species and one Aspergillus species, isolated from spoiled par-baked bread. By comparing agar and liquid-based assays, it was found that the hydrophobic nature of these compounds led to an underestimation of the activity in agar-based assays. In liquid medium, it was possible to evaluate the effect quantitatively and differentiate between strong and weak inhibitors. Of the most interesting compounds, the minimal inhibitory concentration (MIC) was determined, and synergistic interactions were studied. This revealed an interesting interaction between benzyl isothiocyanate and carvacrol, which was further investigated through validation in par-baked bread. Antifungal efficacy was assessed in a shelf life and challenge test, revealing that spray application of 200 to 400 µg/mL benzyl isothiocyanate and 1000 to 2000 µg/mL carvacrol significantly increased shelf life. Furthermore, application of benzyl isothiocyanate and carvacrol was as effective as 0.15% propionic acid was incorporated in the dough. A sensory triangle test indicated that benzyl isothiocyanate and carvacrol influenced the flavour of fully baked bread; however, the effect was not perceived negatively. Full article

The article presents the results of a study aimed at determining the impact of storage conditions on the gas-forming tendency of standard samples (cores) made from moulding sand using a two-component binder based on resole-type phenolic resin, cured with a dedicated ester mixture. The objective of the research was to determine the total volume of gases released as a result of contact between the cores or moulds and the high temperature of molten casting alloys, as well as the rate of gas release, which can influence the tendency for gas-related casting defects. Additionally, the influence of storage conditions on the gas-forming tendency of the samples was evaluated in terms of their environmental and occupational health impact, based on the emission of BTEX compounds (benzene, toluene, ethylbenzene, and xylenes), which serve as key indicators of the harmfulness of moulding and core sands to the surrounding environment. Full article