Search Results (8,127)

The rolling process is one of the most efficient methods for manufacturing long products with both regular and more complex cross-sectional shapes, the latter requiring the development of geometrically complex roll passes. Railway rails are one such product, manufactured at ArcelorMittal Poland S.A., Huta Królewska plant. During the rolling process, the roll passes are subject to wear due to several concurrent phenomena, such as mechanical fatigue, abrasive wear, and thermal fatigue. The determination of roll wear can be based on the experience of personnel and statistical data from previous production runs. It is also possible to determine roll wear through numerical modelling using Archard’s wear model. The aim of this paper is to define a methodology for the quantitative and qualitative determination of roll wear, as well as to establish a wear coefficient dependent on the type of plastic forming process. This will enable the development of a new roll pass design for railway rails that takes into account the durability of the roll passes. Full article

Saturated and branched high molecular weight organic esters are highly valued as emollients in the cosmetic industry due to their superior properties. Their saturated character provides resistance to oxidation and rancidity. Additionally, their branched structure endows them with low melting temperatures, enabling them to remain liquid over a broad temperature range. These esters can be obtained from branched alcohols, branched fatty acids or both, using chemical or enzymatic processes. Among branched alcohols, Guerbet alcohols stand out. Due to their characteristic properties as branched, saturated alcohols with superior oxidative stability and extremely low volatility, they are proposed as excellent substrates for the enzymatic synthesis of these compounds. This study represents the first investigation into the biocatalytic synthesis of three specific esters: those formed between 2-octyl-1-dodecanol (C20 Guerbet alcohol) and the fatty acids myristic (MA), palmitic (PA), and stearic acid (SA). To achieve this, an environmentally sustainable biocatalytic process was developed. The synthesis involves a solvent-free esterification catalyzed by the commercial immobilized lipase, Lipozyme^® 435, conducted within a vertically stirred, thermostated batch tank reactor. Optimal conditions for lipase concentration and temperature were established, and the sustainability of the process was successfully quantified using various “green metrics”. Full article

Long-duration space missions expose astronauts to galactic cosmic radiation (GCR), a complex spectrum of high-charge, high-energy (HZE) ions that pose significant risks of chronic tissue injury. To model these effects, we examined intestinal outcomes in wild-type mice 5 months after low-dose (50 cGy) 33-ion mixed-field GCR simulation (GCRsim). GCRsim induced sustained DNA double-strand breaks (DSBs) and oxidative stress, as shown by elevated γH2AX foci and 4-HNE staining. Intestinal epithelial cells (IECs) exhibited pronounced senescence, marked by increased SA-β-gal activity, p16 upregulation, LaminB1 loss, and induction of senescence-associated secretory phenotype (SASP) cytokines (Cxcl10, IL-6, IL-1β, Icam1). GCRsim also elevated circulating LINE-1 DNA and reduced expression of DNA-degrading nucleases (DNase2, TREX1), indicating impaired extracellular DNA clearance. Targeted molecular study revealed persistent activation of the cGAS–STING pathway, with elevated cGAS, STING, pTBK1, pIKKα/β, and nuclear pIRF3, pIRF7, and p65, consistent with chronic innate immune signaling. Functionally, GCRsim altered nutrient absorption gene expression—upregulating glucose transporters (Slc2a2, Slc2a5, Slc5a1) and gut hormones (Cck, Gip), while downregulating cholesterol/fat transporters (Npc1, Npc1l1). Biochemical markers supported intestinal injury, with decreased serum citrulline and increased intestinal fatty acid-binding protein (I-FABP), indicating barrier compromise. Collectively, these findings demonstrate that GCRsim drives sustained intestinal dysfunction, highlighting the need for countermeasures to protect GI health during deep-space missions. Full article

A two-year field study was performed to evaluate the cadmium (Cd) phytoremediation potential of two hyperaccumulators, Sedum alfredii (S.A.) and Sedum plumbizincicola (S.P.), in contaminated farmland. Biomass and Cd uptake in both species followed logistic growth models. S.A. reached maturity about 20 days earlier than S.P., with optimal harvest timing at the early late-flowering stage (early–mid May), compared to the full late-flowering stage (early June) for S.P. The primary Cd-accumulating organs were stems and flowers in S.A. and leaves and stems in S.P. Under identical conditions, S.P. exhibited higher theoretical biomass, Cd content, bioconcentration factor (BCF), and Cd uptake, supported by transcriptomic data showing upregulation of metal transporter and stress-related genes under Cd exposure. However, S.P. demonstrated greater environmental sensitivity and lower stress resistance, resulting in more variable real-world remediation efficiency than S.A. It is recommended to harvest at flowering stages, enhance biomass in key Cd-accumulating tissues, and select species based on local conditions. Future work should aim to breed Sedum varieties with greater biomass, Cd accumulation capacity, and stress tolerance. This study provides actionable insights for optimizing the timing and species selection in Cd phytoremediation. Full article

We report the experimental observation of dissipative solitons (DS) in an erbium-doped fiber laser mode-locked with ethylene glycol. Stable individual dissipative solitons with the fundamental repetition frequency of 35.17 MHz are obtained. The spectral profiles exhibit dynamic variation, adopting either a parabolic-like or an M-like shape at varying pump levels. Moreover, through increasing the pump power and/or appropriately regulating the polarization controller, multiple dissipative solitons, including soliton pairs and soliton triplet states have also been achieved. The generation mechanism is attributed to the phenomenon of peak clamping effect. This is the first demonstration of a dissipative soliton laser utilizing ethylene glycol as a saturable absorber. It is anticipated that this demonstration will spur further attention on organic liquid SAs and potentially extend significant influence for the application of ultrafast lasers. Full article

In response to the problem of high energy consumption caused by inefficient temperature control of energy storage aggregates in traditional building envelope structures, this study developed a decanoic acid–stearic acid composite phase-change ceramsite aggregate to improve the thermal performance of buildings and promote the utilization of solid waste resources. Based on the theory of minimum melting, composite phase-change materials were screened through thermodynamic models. The capric acid–stearic acid (CA-SA) melt system, whose theoretical phase-transition temperature falls within the building indoor thermal environment control range (18–26 °C), was preferred as the experimental object of this study, and its characteristics were verified through step cooling curves and thermal property tests. Subsequently, the ceramsite adsorption process was optimized, and the encapsulation process was studied. Finally, the encapsulation performance was evaluated through thermal stability and stirring crushing rate tests. The results showed that the phase-transition temperature of the decanoic acid–stearic acid melt system was 24.83 °C, which accurately matched the indoor thermal environment control requirements. The ceramsite particles treated by a physical vibrating screen can reach equilibrium after 30 min of adsorption at room temperature and pressure, which is both efficient and economical. The encapsulation layer of sludge biochar cement slurry with a water–cement ratio of 0.5 and a biochar content of 3% has both thermal conductivity and encapsulation integrity. The thermal stability test showed that the percentage of leakage of sludge biochar cement slurry and epoxy resin encapsulated aggregates was 0%, and the thermal stability rating was “very stable”. However, the percentage of leakage of unencapsulated and spray-coated encapsulated aggregates was as high as 193% and 40%, respectively. The results of the mixing and crushing rate test show that although the mixing and crushing rate of sludge biochar cement slurry encapsulation is slightly higher, its production cost is much lower than that of epoxy resin, and it is also environmentally friendly. This study improves the thermal performance of buildings by using composite phase-change ceramsite aggregate, and simultaneously realizes the resource utilization of sludge biochar, providing a solution for building energy saving and efficiency that combines environmental and engineering value. Full article

Background/Objectives: Achieving and maintaining a smooth restoration surface is clinically significant, as surface roughness is linked to plaque accumulation, staining, and wear. This study aimed to evaluate in vitro the effect of different polishing paste systems on reducing surface roughness and to assess their performance after simulated post-operative maintenance through toothbrushing. Methods: A total of 128 cylindrical, flat-surface specimens were fabricated from a nanohybrid composite (Filtek Supreme XTE, 3M, USA) using a standardized metal mold. All specimens were finished with silicon carbide paper and polished with a two-step rubber disc system (Hi-Luster, Kerr, USA). They were then randomly assigned to 16 groups (n = 8) according to the polishing protocol. One group was polished with a prophylaxis paste, while the other fifteen groups were treated with pastes indicated for composite and/or ceramic materials. Polishing was performed with a flat buff wheel. To simulate clinical maintenance, specimens underwent a standardized toothbrushing cycle equivalent to three months of use. Surface roughness parameters (Sa and Sq) were measured at three stages with an optical profilometer: after initial polishing, after paste application, and after simulated toothbrushing. Results: Mean Sa values ranged from 0.065 to 0.560 and Sq values from 0.075 to 0.676. Significant differences were found among pastes for both parameters (p < 0.05). Two-way ANOVA revealed significant differences after polishing paste application, both before and after toothbrushing (p < 0.05). Toothbrushing increased roughness in most groups (p < 0.05), although no significant deterioration was observed for nine pastes in Sa and eight in Sq (p ≥ 0.05). Conclusions: Polishing pastes vary in effectiveness, and not all produce measurable improvements in surface smoothness. Their efficiency appears to be unrelated to the abrasive or the number of steps. Simulated toothbrushing over a three-month period may reduce the initial benefits, emphasizing the importance of careful clinical selection. Full article

Efficient operation of robotic manipulators in constrained workspaces requires careful coordination of robot placement, motion planning, and posture optimization. This paper presents a hierarchical optimization framework that addresses these challenges for robot placement, motion planning, and posture determination for multi-target manipulation tasks. Initially, the workspace layout is optimized using an adaptive genetic algorithm to determine robot placement that maximizes reachability and task efficiency. Subsequently, a surrogate-assisted rapidly-exploring random tree (SA-RRT) algorithm generates collision-free paths from the start to target configurations, leveraging machine learning models to reduce computational cost while preserving path quality. Finally, the robot’s posture is optimized via a second genetic algorithm to achieve a single configuration that allows rapid access to all target positions. The effectiveness of the proposed framework was evaluated through extensive simulations in a Unity-based environment, comparing SA-RRT against the conventional target-biased nearest neighbor (TNN-RRT) algorithm. In particular, the proposed SA-RRT algorithm reduces path planning computation time by 76.17% compared to TNN-RRT and also yields lower path cost, demonstrating both efficiency and path quality improvement. Overall, the framework provides a unified methodology for integrating layout planning, motion planning, and posture optimization, facilitating more effective deployment of robotic manipulators in industrial environments. Full article

The long-term corrosion protection of copper surfaces modified with self-assembled hydrophobic layers (SAHLs) based on stearic acid (SA) and two fat-soluble vitamins, vitamin K₃ (menadione) and vitamin E (E307), was investigated in simulated acidic urban rain (pH 5) over 7 days. The SAHLs were characterised by SEM, contact angle goniometry, ATR-FTIR, potentiodynamic polarisation, and electrochemical impedance spectroscopy (EIS). Surface modification was achieved by immersing copper samples in ethanolic SA solutions containing 2.0 wt% of fat-soluble vitamins. Variants included individual additives, (SA + 2.0 wt% K₃) and (SA + 2.0 wt% E307), as well as mixtures with a constant total additive content of 2.0 wt%: (SA + [1.5 wt% K₃ + 0.5 wt% E307]) and (SA + [1.0 wt% K₃ + 1.0 wt% E307]). The (SA + 2.0 wt% K₃) modification produced needle-like microstructures with strong short-term inhibition but poor long-term stability, while (SA + 2.0 wt% E307) formed smoother, more stable films. The mixture containing equal mass fractions of vitamins, (SA + [1.0 wt% K₃ + 1.0 wt% E307]), exhibited a synergistic effect, yielding hierarchically structured, flower-like morphologies with high polarisation resistance and stable impedance over 7 days. These results show that combining K₃ and E307 with stearic acid provides robust, environmentally friendly, and durable protection for copper surfaces. Full article

In this study, the J-integral method was used to evaluate the fracture toughness (J_Q) of the isolation layer at the top of SA508-III-309L/308L-316L dissimilar metal welded joints (DMWJs) of a pressure vessel. Tests were carried out at varying temperatures, from room temperature to 320 °C, to study the mechanism underlying temperature effects on unstable crack propagation. The results show that failure occurs in the middle position of the weld isolation layer of the welded joint at all test temperatures. The J_Q of the inner diameter of the joint decreases with increased temperature, with a maximum decrease of 31.8%. The analysis shows that the lath ferrite structure in the isolation layer provides a favorable path for crack propagation. The increase in temperature enlarges the difference in thermal expansion between SA508-III steel and the isolation layer, making it easier for second-phase particles in the isolation layer to induce crack initiation and propagation, thus reducing the J_Q of the steel. In addition, at high temperatures, the dislocation density of the isolation layer, the deformation resistance of the material, and the difference in the yield ratio of the joint weld all decrease, which is not conducive to the redistribution of the stress field at the tip of the fatigue crack, leading to further reduction in the J_Q. Full article

This study evaluated the performance and energy and nutrient utilization of broiler chickens fed corn-soybean meal-based diets supplemented with a naturally fermented enzyme complex containing xylanase and phytase. This was evaluated using 300 one-day-old male Cobb broiler chicks in a randomized complete block design with five dietary treatments replicated 10 times with 6 chicks per replicate. The treatments consisted of a positive control (PC) group containing commercially recommended energy and nutrient levels, a negative control (NC) group with reduced metabolizable energy, calcium, and available phosphorus, and three levels of exogenous enzyme supplementation to the NC diet at 150, 200, 250 mg/kg, respectively. At the end of the trial, ileal digesta and excreta were collected for nutrient and energy digestibility and utilization determination, while tibia bones were collected for bone ash determination. The data was analyzed using Proc GLM of SAS 9.4 v 4. Enzyme supplementation quadratically increased (p < 0.05) average daily gain, average daily feed intake (ADFI), and feed efficiency during days 9–21. There was also a linear increase (p < 0.01) between enzyme level and ADFI during days 0–21. Compared with birds fed the PC diet, chickens fed the NC diet had lower (p < 0.01) utilization of DM, N, Ca, P, and energy, as well as lower (p < 0.01) apparent ileal digestibility of essential and non-essential amino acids (AA). Enzyme supplementation level showed a quadratic relation (p < 0.01) with the utilization of DM, N, Ca, P, and AMEn, as well as with the apparent ileal digestibility of essential and non-essential AA. A quadratic relationship was also observed for apparent ileal digestibility of DM, N, P, and digestible energy, except for Ca, where the relationship was linear (p < 0.001). Bone breaking strength and bone ash quadratically correlated (p < 0.05) with the level of enzyme supplementation. The results from this study indicated that the supplementation of exogenous enzyme to a corn–soybean meal-based diet resulted in benefits to performance, nutrient digestibility and utilization, and bone mineralization of broiler chicks compared to birds on the NC diet. Full article

Background/Objectives: miR5200 is miRNA unique to Poaceae plants. Induced under short-day conditions, it modulates flowering time by regulating the florigen FT gene expression. However, to date, the genetic locus responsible for mature miR5200 formation remains experimentally unvalidated, and its biological function in abiotic stress responses remains unknown. This has hindered systematic elucidation of miR5200’s physiological role and molecular mechanisms. Methods: This study utilized wheat as the research material. First, through bioinformatics analysis at the genomic level, 13 potential candidate tae-miR5200 gene loci were screened. Subsequently, the authenticity of these gene loci was systematically validated by combining tobacco transient transfection-based GUS staining assay and quantitative real-time PCR (qRT-PCR) to detect expression levels. Building upon this foundation, the expression patterns of tae-miR5200 under abiotic stresses such as low temperature, drought, and salinity, as well as SA, ABA, IAA, GA₃, and MeJA treatments, were further investigated. Results: Experimental validation confirmed that 7 out of 13 potential gene loci are authentic and functional, and tae-miR5200 exhibited specific expression changes under different types of abiotic stress. Conclusions: This study confirms the authenticity of tae-miR5200 gene loci, effectively eliminating interference from bioinformatics-predicted false-positive loci in subsequent functional studies. It provides an experimental foundation for further investigation into the molecular mechanisms of tae-miR5200 in wheat responses to abiotic stress. Full article

Soluble solids content is the most important attribute related to the quality and price of apples. The objective of this study was to detect the soluble solids content (SSC) in ‘Fuji’ apples using hyperspectral imaging combined with a deep learning algorithm. The hyperspectral images of 570 apple samples were obtained and the whole region of apple sample hyperspectral data was collected and preprocessed. In addition, a method involving multi-attention convolutional neural network (MA-CNN) is proposed, which extracts spectral and spatial features from hyperspectral images by embedding channel attention (CA) and spatial attention (SA) modules in a convolutional neural network. The CA and SA modules help the network adaptively focus on important spectral–spatial features while reducing the interference of redundant information. Additionally, the Bayesian optimization algorithm (BOA) is used for model hyperparameter optimization. A comprehensive evaluation is conducted by comparing the proposed model with CA-CNN models, SA-CNN, and the current mainstream models. Furthermore, the best prediction performances for detecting SSC in apple samples were obtained from the MA-CNN model, with an ${\mathrm{R}}_{\mathrm{p}}^2$ value of 0.9602 and an RMSEP value of 0.0612 °Brix. The results of this study indicated that the MA-CNN algorithm combined with hyperspectral imaging technology can be used as an effective method for rapid detection of apple quality parameters. Full article

This paper explores how the deployment of “High-Performance Heat-Powered Heat Pumps” (HP³s)—a novel heating technology—could help meet the domestic heating demand in the UK and reduce how much grid-scale energy storage is needed in comparison to a scenario where electrical heat pumps fully supply the heating demand. HP³ systems can produce electricity, which can partially alleviate the stress caused by electrical heat pumps. A parametric analysis focusing on two variables, the penetration of HP³ systems (H) and the amount of electricity exported (Ɛ), is presented. For every combination of H and Ɛ, the electricity system is optimized to minimize the cost of electricity. Three parameters define the electricity system: the generation mix, the energy storage mix and the amount of over-generation. The cost of electricity is at its highest when electrical heat pumps supply all demand. This reduces as the penetration of HP³ systems increases due to a reduction in the need for energy storage. When HP³ systems supply 100% of the heating demand, the total cost of electricity and the storage capacity needed are 6% and 50% lower, respectively, compared to a scenario where electrical heat pumps are in 100% of residences. Full article

Aiming at the problems of complex image background and numerous interference factors faced by visual navigation systems in orchard environments, this paper proposes an orchard navigation line recognition method based on U-Net. Firstly, the drivable areas in the collected images are labeled using Labelme (a graphical tool for image annotation) to create an orchard dataset. Then, the Spatial Attention (SA) mechanism is inserted into the downsampling stage of the traditional U-Net semantic segmentation method, and the Coordinate Attention (CA) mechanism is added to the skip connection stage to obtain complete context information and optimize the feature restoration process of the drivable area in the field, thereby improving the overall segmentation accuracy of the model. Subsequently, the improved U-Net network is trained using the enhanced dataset to obtain the drivable area segmentation model. Based on the detected drivable area segmentation mask, the navigation line information is extracted, and the geometric center points are calculated row by row. After performing sliding window processing and bidirectional interpolation filling on the center points, the navigation line is generated through spline interpolation. Finally, the proposed method is compared and verified with U-Net, SegViT, SE-Net, and DeepLabv3+ networks. The results show that the improved drivable area segmentation model has a Recall of 90.23%, a Precision of 91.71%, a mean pixel accuracy (mPA) of 87.75%, and a mean intersection over union (mIoU) of 84.84%. Moreover, when comparing the recognized navigation line with the actual center line, the average distance error of the extracted navigation line is 56 mm, which can provide an effective reference for visual autonomous navigation in orchard environments. Full article