Search Results (5,286)

Aiming at the challenges faced by the detection of small-scale ship targets in Synthetic Aperture Radar (SAR) images, this paper proposes a novel deep learning network named FAWT-Net based on attention-matrix despeckling and Haar wavelet reconstruction. This network collaboratively optimizes the detection performance through three core modules. First, during the feature transfer stage from backbone to the neck, a filtering module based on attention matrix is designed, which can suppress the speckle noise. Then, during feature upsampling stage, a wavelet transform feature upsampling method for reconstructing image details is designed to enhance the distinguishability of target boundaries and textures. At the same time, the network also combines sub-image feature stitching downsampling to avoid losing key details in small targets, and adopts a scale-sensitive detection head. By adaptively adjusting the shape constraints of prediction boxes, it effectively solves the regression deviation problem of ship targets with inconsistent aspect ratios. Verified by experiments on SSDD and LS-SSDD, the proposed method improves AP50 by 1.3% and APS by 0.8% on the SSDD. Meanwhile, it is verified that the proposed method has higher precision and recall rates on the LS-SSDD, and the recall rate has been increased by 2.2%. Full article

Asphalt is a widely used polymeric material in pavement engineering. However, it is easily affected by heat and ultraviolet rays, which accelerate its molecular degradation and physicochemical aging, thereby limiting its service life. To improve the anti-aging properties of asphalt, three types of nano-zinc oxide (ZnO)-modified asphalt were prepared. The chemo-rheological behavior, structural evolution of polymeric components, molecular weight distribution, and nanoscale morphology of nano-ZnO-modified asphalt were studied via dynamic shear rheometry (DSR), Fourier transform infrared spectrometry (FTIR), gel permeation chromatography (GPC) and atomic force microscopy (AFM), and the aging resistance of nano-ZnO-modified asphalt was quantitatively analyzed using the rutting factor index, functional group index, molecular size ratio, and nanoscale parameters. The findings indicate that nano-ZnO enhances the high-temperature rheological properties of asphalt and delays the increase in the rutting factor of aged asphalt. Nano-ZnO is dispersed in the asphalt matrix in the form of a physical mixture without inducing new chemical bonds, and can reduce the nanoscale roughness of asphalt. After aging, the nanoscale roughness and the aspect ratio of the bee structure decreased, and the bee structure area increased. According to the changes in the functional group index and the proportions of molecular sizes in the asphalt, it was found that nano-ZnO can significantly improve asphalt’s aging resistance. The results of this study provide insights into the nanoscale modification and structure–property relationships of polymeric asphalt binders, providing a reference for the design and application of functional polymer nanocomposite systems with improved durability. Full article

Deicing salt effectively melts ice and snow to maintain traffic flow in seasonal freezing zones, but its erosion effect compromises the water stability and structural integrity of asphalt pavements. To comprehensively explore the impacts of salt erosion on the interfacial behaviors of rubber asphalt–aggregate systems, this study developed a multiscale characterization method integrating a macroscopic mechanical test, microscopic tests, and molecular dynamics (MD) simulations. Firstly, laboratory-controlled salt–freeze–thaw cycles were employed to simulate field conditions, followed by quantitative evaluation of interfacial bonding properties through pull-out tests. Subsequently, the atomic force microscopy (AFM) and Fourier transform infrared spectrometer (FTIR) tests were conducted to characterize the microscopic morphology evolution and chemical functional group transformations, respectively. Moreover, by combining the diffusion coefficients of water molecules, salt solution ions, and asphalt components, the mechanism of interfacial salt erosion was elucidated. The results demonstrate that increasing NaCl concentration and freeze–thaw cycles progressively reduces interfacial pull-out strength and fracture energy, with NaCl-induced damage becoming limited after twelve salt–freeze–thaw cycles. In detail, with exposure to 15 freeze–thaw cycles in 6% NaCl solution, the pull-out strength and fracture energy of the rubber asphalt–limestone aggregate decrease by 50.47% and 51.57%, respectively. At this stage, rubber asphalt exhibits 65.42% and 52.34% increases in carbonyl and sulfoxide indexes, respectively, contrasted by 49.24% and 42.5% decreases in aromatic and aliphatic indexes. Long-term exposure to salt–freeze–thaw conditions promotes phase homogenization, ultimately reducing surface roughness and causing rubber asphalt to resemble matrix asphalt morphologically. At the rubber asphalt–NaCl solution–aggregate interface, the diffusion of Na⁺ is faster than that of Cl⁻. Meanwhile, compared with other asphalt components, saturates exhibit notably enhanced mobility under salt erosion conditions. The synergistic effects of accelerated aging, salt crystallization pressure, and enhanced ionic diffusion jointly induce the deterioration of interfacial bonding, which accounts for the decrease in macroscopic pull-out strength. This multiscale investigation advances understanding of salt-induced deterioration while providing practical insights for developing durable asphalt mixtures in cold regions. Full article

The present research aims to investigate the impact of various mixing techniques (centrifugal planetary mixing, ultrasonication, and high-temperature magnetic stirring) on the properties of nanocomposite epoxy resins using expanded graphite particles. Differential scanning calorimetry reveals that the curing behavior and glass transition temperature are influenced by the selected method, indicating that a suitable choice allows increasing curing degree (C.D.) and glass transition temperature up to 10% and 12%, respectively. Morphological analysis performed via Scanning Electron Microscopy and Tunneling Atomic Force Microscopy offers detailed insights into the dispersion characteristics of fillers within polymer matrices, which sensitively affect the properties of the materials. The electrical conductivity values vary by more than five orders of magnitude among the various mixing methods. Centrifugal mixing leads to a decrease in the equilibrium concentration of water (C_eq) by up to 23% compared to that of the unfilled matrix, thanks to the chemical interactions that occur between the graphitic particles and the epoxy matrix (detectable via Fourier Transform Infrared Spectroscopy). Such a reduction is strongly desired in strategic fields such as the transport sector. The analysis of the obtained results suggests choosing the dispersion method of the filler in the matrix by considering the required performance for the specific planned application. Full article

Quality 4.0 is a new concept that integrates Industry 4.0 technologies into traditional quality management systems in order to reduce operational cost, time and improve efficiency. This article presents an overview of the transformation towards Quality 4.0 and reviews articles published in Scopus, ScienceDirect, and Web of Science in order to have accurate, up-to-date, and relevant information. This work focuses on the Industry 4.0 technologies applied in Quality management systems that can support the transformation to Quality 4.0, the challenges of these technologies can address, and the benefits of implementing Quality 4.0. The results analyze the critical benefits of implementing digital technologies, including operational efficiency and improved innovation. Practical cases and real-life experiences are discussed. Finally, we identified a quantitative matrix reflecting the frequency of specific technologies associated with particular quality challenges. Full article

Nectar composition varies across plant species and environments, influencing pollinator interactions and honey quality. Reliable methods for nectar discrimination, however, remain limited. Here, we demonstrate the use of Fourier-transform infrared (FTIR) spectroscopy combined with chemometric analysis to differentiate nectar samples of Echium vulgare (E. vulgare) and Hedera helix (H. helix) collected in urban locations. Among eight tested preprocessing strategies, simple approaches such as Savitzky–Golay smoothing or even raw spectra provided the best clustering results. The most discriminative spectral regions were consistently the carbohydrate fingerprint (1200–950 cm⁻¹) and the C–H stretching zone (2935–2885 cm⁻¹). Mean spectra and PCA confirmed that variability between locations arises mainly from carbohydrate-associated bands, while solvent type, biological matrix, and environmental exposure also affect spectral fingerprints. These results highlight FTIR spectroscopy as a rapid, non-destructive, and robust method for nectar discrimination, with potential applications in food authentication, ecological research, and pollinator–plant studies. Full article

In this study, the oxidative upgrading of heavy oil residues using polymer-containing waste for the sustainable production of bitumen was investigated. Oxidation was performed at temperatures of 250–270 °C for 3–4 h with the addition of 2–3 wt.% polyethylene-based waste, under an air flow of 7 L/min. The physical and mechanical characterization of the resulting bitumen demonstrated compliance with oxidized modified bitumen grades OMB 100/130 and OMB 70/100. FTIR spectroscopy revealed the formation of carbonyl and sulfoxide functional groups, indicating the effective oxidative transformation of the bitumen matrix and partial incorporation of polyethylene fragments. NMR spectroscopy confirmed increased aromaticity and carbonyl content, while also detecting polyethylene-derived signals, suggesting compatibility and integration of the polymer waste into the oxidized structure. The thermal and rheological results showed that the optimal conditions for producing high-quality oxidized bitumen involved the use of 2% polymer waste at 270 °C for 4 h, yielding enhanced physical properties and chemical stability. These findings support the feasibility of using polymer-containing waste for bitumen upgrading, offering both environmental and technical advantages. The method not only improves the quality of bitumen but also contributes to waste valorization and circular economy practices in the road construction industry. Full article

Impaired bone regeneration and wound healing represent a major clinical and socioeconomic challenge for our aging and multimorbid population. Fracture and wound healing share many common features, with transforming growth factor beta (TGF-β) being a key regulator of inflammation, angiogenesis, fibroblast activation, and matrix remodeling. The dysregulation of TGF-β signaling is a hallmark of chronic wounds, excessive scar formation, and fracture non-union. Extracellular matrix protein 1 (ECM1) plays a crucial role in the activation of latent TGF-β. As a protein of the extracellular matrix, ECM1 offers ideal conditions for the biofunctionalization of bone implants or wound patches. Its mode of action has been studied mainly in fibrosis models of the liver or heart, where TGF-β acts as a driver of the disease. The controlled knock-out or overexpression of ECM1 either promoted or improved fibrosis development. In this review, we discuss how these findings can be applied to the biofunctionalization of implants to support bone and wound healing, considering the impact of TGF-β on the different healing phases. Full article

Hydroxypropyl methylcellulose (HPMC) is a biocompatible polymer widely used in topical formulations due to its suitable rheological behavior, film-forming capacity, and good compatibility with different active pharmaceutical ingredients. The present study demonstrates the potential of HPMC-based gels for dermal delivery of porphyrinic photosensitizers, aiming to enhance the efficiency of photodynamic therapy (PDT) in potential skin cancer applications. HPMC-based gel incorporating two previously synthesized porphyrinic photosensitizers, named 5,10,15,20-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1) and 5-(4-hydroxy-3-methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.2), was developed and carefully characterized regarding its rheological behavior, texture, and in vitro activity. Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), atomic force microscopy (AFM), fluorescence, and UV-Vis spectroscopy were carried out to evaluate the structural and morphological changes induced by the incorporation of the porphyrins in the HPMC gel matrix. The gels were subsequently evaluated by pharmacotechnical analysis, including pH (7.2 for both HPMC-P2.1 and HPMC-P2.2), viscosity, spreadability, texture profile analysis, and drug content uniformity. Rheological behavior confirmed the pseudoplastic behavior, suggesting a structured system with a gel-like consistency, while physical measurements demonstrated the stability and preserved functionality of the photosensitizers within the HPMC matrix. In vitro studies revealed an efficient cellular internalization of selected porphyrins into human epidermoid carcinoma cells, a critical requirement for topical PDT applications. The study highlights the capability of HPMC gels to serve as effective delivery platforms for porphyrin-based photosensitizers, supporting their application in localized skin cancer treatment through PDT. Full article

The Na₂O-SrO-SiO₂ system shows promise in the development of glasses that can be transformed into electrically conductive glass ceramics. The conventional processing of such materials usually involves the synthesis of a parent glass, followed by a complex devitrification treatment. This study proposes a simplified approach based on the use of preceramic polymers, namely silicone resins combined with oxide fillers. These systems yield silicate-based ceramics through direct heat treatment, replicating the phase assembly of traditional glass ceramics with no need for prior glass melting. A printable formulation was developed by mixing a silicone resin with an acrylate-based photocurable resin, sodium nitrate and strontium carbonate. The resulting ‘suspension-emulsion’ was later shaped into monolithic components using digital light processing. After pyrolysis in nitrogen atmosphere, the components transformed into SrSiO₃ crystals embedded in a composite matrix, in turn composed of glass and turbostratic carbon (the latter specifically offered by the silicone polymer). This combination of crystalline silicates and carbon resulted in measurable electrical conductivity. This study confirms that silicone-derived systems can serve as effective precursors for conductive glass-ceramic analogues, providing an alternative to conventional methods with single-step processing. This approach enables structural shaping through 3D printing and the development of functional properties suitable for electronic or electrochemical applications. Full article

This study addresses the critical need for sustainable material development by thoroughly investigating the synergistic effects of artichoke stem waste (ASW) and titanium dioxide nanoparticles (TiO₂ NPs) on the properties of epoxy matrix composites. This research uniquely utilizes stereolithography (SLA)-based 3D printing technology for the fabrication and characterization of polymer matrix composites. The study systematically investigates three distinct composite formulations: artichoke stem waste/epoxy, TiO₂ nanoparticles/epoxy, and a novel hybrid of artichoke stem waste/TiO₂ nanoparticles/epoxy composites. Each formulation was prepared at three different loading concentrations to determine their optimal performance. The fabricated composites underwent comprehensive characterization, including meticulous evaluations of their mechanical (tensile), thermal (Thermogravimetric Analysis (TGA)), morphological (Scanning Electron Microscopy (SEM)), and chemical-bonding (Fourier Transform Infrared (FT-IR) spectroscopy) properties. Additionally, X-ray Diffraction (XRD) and FT-IR analyses were performed to structurally characterize the raw materials (pristine (cured epoxy), ASW, and TiO₂ NPs) and the final composite structures. The findings indicate that the incorporation of ASW and TiO₂ NPs significantly enhances the performance of epoxy composites. This discovery is significant as it demonstrates the successful valorization of agricultural waste into high-performance composite materials and advances the capabilities of 3D printing technology in sustainable materials science. The results of this study offer critical insights, substantially contributing to the development of sustainable and high-value materials. Full article

The rational delineation of open-pit mining areas constitutes the core foundation for achieving safe, efficient, economical, and sustainable mining operations. The quality of this decision-making directly impacts the economic benefits experienced throughout the mine’s entire lifecycle and the efficiency of resource recovery. Traditional open-pit mining area delineation relies on an experience-driven manual process that is inefficient and incapable of real-time dynamic data optimization. Thus, there is an urgent need to establish an intelligent decision-making model integrating multi-source data and multi-objective optimization. To this end, this study proposes an intelligent mining area division algorithm. First, a geological complexity quantification model is constructed, incorporating innovative adaptive discretisation resolution technology to achieve precise quantification of coal seam distribution. Second, based on the quantified stripping-to-mining ratio within grids, a block-growing algorithm generates block grids, ensuring uniformity of the stripping-to-mining ratio within each block. Subsequently, a matrix of primary directional variations in the stripping-to-mining ratio is constructed to determine the principal orientation for merging blocks into mining areas. Finally, intelligent open-pit mining area delineation is achieved by comprehensively considering factors such as the principal direction of mining areas, geological conditions, boundary shapes, and economic scale. Practical validation was conducted using the Shitoumei No. 1 Open-Pit Coal Mine in Xinjiang as a case study in engineering. Engineering practice demonstrates that adopting this methodology transforms mining area delineation from an experience-driven to a data-driven approach, significantly enhancing delineation efficiency. Manual simulation of a single scheme previously required approximately 15 days. Applying the methodology proposed herein reduces this to just 0.5 days per scheme, representing a 96% increase in efficiency. Design costs were reduced by approximately CNY 190,000 per iteration. Crucially, the intelligently recommended scheme matched the original design, validating the algorithm’s reliability. This research provides crucial support for theoretical and technological innovation in intelligent open-pit coal mining design, offering technical underpinnings for the sustainable development of open-pit coal mines. Full article

Phase transformations significantly influence the mechanical properties of Fe-based alloys, making their understanding essential for the design of high-performance alloy materials. This study investigates microstructural evolution and martensitic transformations induced by B2 phase precipitation in an Fe-20Ni-4.5Al-1.0C (wt.%) alloy. The alloy was solution-treated at 1100 °C, followed by isothermal holding between 750 °C and 1000 °C, and water quenching. Microstructural analysis revealed that the as-quenched alloy consisted of a single-phase austenite (γ). Isothermal holding led to the precipitation of a (Ni,Al)-rich B2 phase within the grains and along grain boundaries. An α′-martensitic phase was also observed within γ-grains adjacent to the B2 precipitates in the isothermally held samples. Martensitic transformation is attributed to localized nickel depletion in the matrix surrounding B2, which reduced γ-phase stability and raised the martensite start temperature (Ms), promoting γ-to-α′ transformation during cooling. The co-existence of B2 and α′ phases significantly increased the hardness of the alloy, with a maximum observed at an 850 °C holding temperature. At higher temperatures, coarsening and partial dissolution of B2, as well reduced martensite formation, led to a decline in hardness. These findings highlight the role of B2 precipitation in promoting martensitic transformation and optimizing mechanical properties through controlled heat treatment. Full article

Urbanization generates large quantities of arsenic-contaminated excavated soils that pose environmental risks due to arsenic volatilization during high-temperature sintering processes. While these soils have potential for recycling into construction materials, their reuse is hindered by arsenic release. This study demonstrated calcium hydroxide (Ca(OH)₂) as a highly effective additive for suppressing arsenic volatilization during soil sintering, while simultaneously improving material properties. Through comprehensive characterization using inductively coupled plasma-mass spectrometry (ICP-MS), scanning electron microscopy (SEM) and X-ray microtomography (μCT), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), results demonstrated that Ca(OH)₂ addition (0.5–2 wt.%) reduces arsenic volatilization by 57% through formation of thermally stable calcium arsenate (Ca₃(AsO₄)₂). Ca(OH)₂ acted via two mechanisms: (a) chemical immobilization through Ca-As-O compound formation, (b) physical encapsulation in a calcium-aluminosilicate matrix during liquid-phase sintering, and (c) pH buffering that maintains arsenic in less volatile forms. Optimal performance was achieved at 0.5% Ca(OH)₂, yielding 9.14 MPa compressive strength (29% increase) with minimal arsenic leaching (<110 ppb). Microstructural analysis showed Ca(OH)₂ promoted densification while higher doses increased porosity. This work provides a practical solution for safe reuse of arsenic-contaminated soils, addressing both environmental concerns and material performance requirements for construction applications. Full article

Jiangsu Province is an important economic province on the eastern coast of China, revealing the spatial–temporal characteristics, dynamic degree, and transition direction of land use/cover change, and its main driving factors are significant for the effective use of land resources and the promotion of regional human–land coordinated development. Based on land use data of Jiangsu Province from 2000 to 2020, this study investigates the spatiotemporal evolution characteristics of land use/cover using the dynamics model and the transfer matrix model, and examines the influence and interaction of the driving factors between human activities and the natural environment based on 10-factor data using Geodetector. The results showed that (1) In the past 20 years, the type of land use/cover in Jiangsu Province primarily comprises cropland, water, and impervious, with the land use/cover change mode mainly consisting of a dramatic change in cropland and impervious and relatively little change in forest, grassland, water, and barren. (2) From the perspective of the dynamic rate of land use/cover change, the single land use dynamic degree showed that impervious is the only land type whose dynamics have positively increased from 2000 to 2010 and 2010 to 2020, with values of 3.67% and 3.03%, respectively. According to the classification of comprehensive motivation, the comprehensive land use motivation in Jiangsu Province in each time period from 2000 to 2010 and 2010 to 2020 is 0.46% and 0.43%, respectively, which belongs to the extremely slow change type. (3) From the perspective of land use/cover transfer, Jiangsu Province is mainly characterized by a large area of cropland transfer (−7954.30 km²) and a large area of impervious transfer (8759.58 km²). The increase in impervious is mainly attributed to the transformation of cropland and water, accounting for 4066.07 km² and 513.73 km² from 2010 to 2020, which indicates that the non-agricultural phenomenon of cropland in Jiangsu Province, i.e., the process of transforming cropland into non-agricultural construction land, is significant. (4) From the perspective of driving factors, population density (q = 0.154) and night light brightness (q = 0.156) have always been important drivers of land use/cover change in Jiangsu Province. The interaction detection indicates that the land use/cover change is driven by both socio-economic factors and natural geographic factors. (5) In response to the dual pressures of climate change and rapid urbanization, coordinating the multiple objectives of socio-economic development, food security, and ecological protection is the fundamental path to achieving sustainable land use in Jiangsu Province and similar developed coastal areas. By revealing the characteristics and driving factors of land use/cover change in Jiangsu Province, this study provides qualitative and quantitative theoretical support for the coordinated decision-making of economic development and land use planning in Jiangsu Province, specifically contributing to sustainable land planning, climate adaptation policy-making, and the enhancement of community well-being through optimized land use. Full article