Search Results (50,073)

Selective laser melting (SLM) offers a promising route for fabricating high-performance Cu–Sn alloys; however, the extremely transient thermal behavior of the molten pool and its influence on microstructural evolution and mechanical properties remain insufficiently understood. In this study, a finite element model based on ABAQUS was developed to simulate the transient temperature field and molten pool dynamics of Cu–10Sn alloy during the SLM process. By systematically varying the volumetric energy density (VED), the interplay among molten pool geometry, thermal characteristics, microstructure, and mechanical performance was investigated through a combination of numerical simulation and experimental investigation. The results reveal that increasing VED significantly enlarges the molten pool dimensions, elevates the peak temperature, and intensifies the maximum heating and cooling rates, thereby altering solidification conditions. At a VED of 208.33 J/mm³, the molten pool reached its maximum dimensions, with a length of 230 μm, a width of 161 μm, and a depth of 85 μm, resulting in the highest relative density within the investigated range (98.33%). Under this processing condition, the Cu–10 wt.% Sn (Cu–10Sn) alloy exhibited microhardness values of 190 HV near the solidified areas of melt pool interior and 208.4 HV near the solidified areas of melt pool boundary, accompanied by an ultimate tensile strength of 494 MPa. These findings elucidate the critical role of molten pool thermal behavior in governing microstructural refinement and mechanical properties of SLM-fabricated Cu–10Sn alloys and provide a mechanistic basis for understanding the effect of process parameters. Full article

In this research, a novel polyarylene ether nitrile (PEN) coating material was fabricated through a facile stepwise polymerization method, which provides metallic substrates used in the oil industry with remarkable corrosion protection performance. A variety of characterization techniques were employed to evaluate the comprehensive properties of the PEN coating materials against a commercially established high-temperature-resistant epoxy coating. Based on the TGA curves, the PEN3 coating exhibited a T_5% value of 521 °C, which was 44.72% higher than that of the epoxy coating. According to the tensile experiment, the PEN coatings demonstrated improved mechanical performance, achieving tensile strength and breaking elongation values of 89.37 MPa and 7.14% (PEN3), respectively, while the epoxy achieved values of 18.67 MPa and 0.32%, respectively. EIS tests revealed that all the PEN coatings exhibited superior corrosion resistance compared to the epoxy coating. Among them, the PEN3 coating remained intact without failure and showed the highest impedance value (5.665 × 10⁷ Ω·cm²), which was two orders of magnitude higher than epoxy. Our research confirmed that the PEN coating material provided enhanced corrosion resistance, thermal stability and mechanical properties, positioning it as an alternative option to replace epoxy coating in prolonging the service life of steel piping in oil field applications. Full article

Resolving the dichotomy between wide detection ranges and low mechanical hysteresis remains a critical challenge in flexible electronics, largely governed by the intrinsic viscoelastic creep of polymeric dielectrics. Drawing inspiration from the distinctive load-bearing mechanisms of traditional Chinese Sparrow Brace architecture, we report a mechanically optimized tilted micro-architecture designed to enhance structural resilience. Unlike conventional soft elastomeric pillars that easily succumb to mechanical failure, this BOPS-based tilted geometry provides excellent load-bearing capacity, effectively preventing premature failure. Finite element analysis (FEA) confirms that this tilted geometry forces a fundamental shift from conventional bulk compression to structural bending. Because this bending-dominated architecture drives rapid elastic recovery, it significantly mitigates the severe effects of the polymer’s viscoelastic creep under the tested loading conditions, achieving reliable signal reversibility with low hysteresis. We fabricated this specific architecture via programmable femtosecond laser direct writing (FsLDW) on biaxially oriented polystyrene (BOPS) films, harnessing the material’s entropy-driven self-growth kinetics. By merging this localized growth mechanism with the architectural design, we effectively bypassed the complexities of traditional molding, achieving mask-free, in situ growth of large-scale, highly uniform dielectric micro-arrays. The resulting sensor delivers a remarkably broad working range (up to ~2.28 MPa) coupled with a negligible recovery error (~1.3%), an agile dynamic response (~70/80 ms), and consistent operational durability. Ultimately, this work combines architecture-inspired structural design with advanced femtosecond laser surface microengineering, providing a conceptually novel and scalable pathway for next-generation flexible sensing. Full article

This communication discusses the problem of depositing equiatomic metal alloy films. It is shown that this problem can be solved using a magnetron equipped with a target constructed using a new “multilayer target” paradigm. This target, sputtered in an argon environment, consists of several parallel metal plates mounted on the magnetron axis. A method based on the equality of the sputtered fluxes generated by the plates is proposed for calculating the geometric dimensions of the plates. This equality leads to a system of algebraic equations, which are proposed to be solved under the assumption of a uniform discharge current density distribution in the sputtering region of the target. The communication describes two types of targets in which the plates have slots of different shapes. In one case, the slots are shaped as sectors of a ring with a given angle. In the other, the plates are shaped as rings. As examples, the geometric dimensions of targets for a balanced magnetron system intended for the deposition of films of equiatomic Ti_0.33Ta_0.33Nb_0.33 and Ti_0.25Ta_0.25Nb_0.25Mo_0.25 alloys are calculated. The presentation is accompanied by the results of individual experiments. This report is preliminary in nature; experimental verification is ongoing. The application of the new paradigm in magnetron target design facilitates the fabrication of films of nanostructured medium- and high-entropy alloys with specified chemical compositions, which is the central theme of the Special Issue devoted to functional nanomaterials. Full article

Single-lap shear joints made from fabric T300/polyphenylene sulfide (T300/PPS) and unidirectional T700/low-melt polyaryletherketone (T700/LM-PAEK) laminates are joined via induction and conduction welding at different processing temperatures. The joints are tested experimentally to investigate the influence of the processing temperature on the damage evolution in the specimens which is tracked using digital image correlation. Cracks grow rapidly in the unwelded parts of the joint interface but assume a stable steady-state propagation rate when reaching the fully welded overlap region. It is found that higher welding temperatures lead to longer weld lengths, which improve the strength and stiffness of the specimens and delay damage initiation. An accelerated crack growth rate indicates that the structure is close to its ultimate load after which the joint fails abruptly as the crack growth becomes unstable. Induction welding temperatures at the upper end of the recommended processing window (330 C for T300/PPS and 385 C for T700/LM-PAEK) result in the joints with the highest load-carrying capacity and slowest crack propagation, but also the least damage tolerance. Full article

The production of cultivated meat relies on in vitro animal cell growth and requires the use of scaffolds that structurally resemble key features of the extracellular matrix (ECM), providing mechanical support and biochemical cues for cell adhesion, proliferation, and differentiation. Electrospinning has emerged as a promising technique for manufacturing three-dimensional edible scaffolds because it is robust, versatile, and capable of producing nanofibers with a high surface area-to-volume ratio, tunable porosity, and ECM-like fibrous architectures. Natural biopolymers are promising candidates for the fabrication of electrospun scaffolds, combining biocompatibility, biodegradability, and processing compatibility with food-grade requirements. However, the absence of fully food-grade electrospinning systems, coupled with limited scalable green-processing strategies, remains a critical barrier to industrial translation. In this context, this review presents recent advances in the food-grade electrospinning of natural biopolymers focused on cultivated meat production. Furthermore, scientific gaps in the development of fully edible scaffolds are discussed, along with the need for alternatives to animal-derived materials and synthetic carrier polymers, considering sustainability, consumer acceptance, and the translation from laboratory-scale studies to industrial systems. Finally, this review outlines a strategic roadmap to accelerate the transition from proof-of-concept studies toward scalable, regulatory-compliant, and industrially viable electrospinning technologies for cultivated meat production. Full article

We report the development of bundled optical-guiding crystal scintillators (OCSs) with ultrafine and uniform scintillator cores (~12 μm) for high-resolution X-ray imaging. Conventional OCS fabrication using iodide scintillators often suffers from iodine volatilization, bubble formation, and core discontinuities, which limit structural uniformity and device reliability. To address these limitations, a hollow-fiber-based fabrication strategy was introduced. Hollow glass fibers were first bundled and drawn without scintillator materials, followed by capillary infiltration of a Tl-doped Cs₃Cu₂I₅ (Tl: CCI) melt. This approach enabled the stable formation of densely packed bundled OCS structures with uniform core diameters of 10–12 μm while suppressing volatilization-induced defects. Radioluminescence measurements confirmed a broad emission peak at ~442 nm, consistent with Tl:CCI scintillation. X-ray imaging experiments demonstrated superior spatial resolution and image contrast compared with a commercial CsI:Tl columnar scintillator. The bundled OCS exhibited an average contrast transfer function (CTF) of 30.7% at ~10 lp/mm, exceeding the reference value. These results demonstrate that the hollow-fiber architecture provides an effective route toward scalable ultrafine-core scintillators and highlight the potential of Tl:CCI-filled OCSs for next-generation high-resolution X-ray imaging. Full article

The frontiers of oceanographic survey and environmental monitoring have been expanded with the rapid development of Unmanned Surface Vehicles (USVs). This report presents the design and construction of a USV based on the ArduSub firmware. Through a stable control architecture and MAVLink communication, the system can be customized for surface applications. The proposed system consists of a modular vehicle design, a high-rate data transmission link implemented using the Pymavlink, and a remote control via the standard joystick protocols. In order to enhance the performance of motion estimation, the triaxial accelerometer is calibrated using the nine-parameter ellipsoid fitting technique, which removes bias, scale factors, and axis misalignment errors. The system is also scalable, providing opportunities for future development in autonomous navigation and multi-sensor integration. Full article

According to the complementary advantages of the composites, the degradation rate, biological activity and physical and chemical properties of the composites were adjusted by using the hydrophilic and bioactive advantages of soy protein isolate (SPI) on the basis of toughening PLA by polycaprolactone (PCL). In this study, soy protein isolate/polylactic acid–polycaprolactone (SPI/PLA–PCL) composite microspheres were fabricated via double emulsion–solvent evaporation. SPI was introduced to regulate hydrophilicity, biodegradation, and bioactivity based on PCL–toughened PLA. The microspheres were characterized by SEM, EDS, FTIR, and XRD. Hydrophilicity, thermal stability, and degradation behavior were evaluated via water contact angle, TG/DTA, and in vitro degradation assays. Biocompatibility, hemocompatibility, and osteogenic activity were assessed through cell adhesion, hemolysis, CCK–8, ALP, alizarin red staining, and mineralization tests. Results confirmed the successful preparation of SPI/PLA–PCL microspheres. SPI incorporation enhanced hydrophilicity, degradation rate, and cell adhesion. The composite microspheres exhibited favorable thermal stability, hemocompatibility, biocompatibility, and osteogenic induction. The 50% SPI/PLA–PCL group performed optimally in cell proliferation, adhesion, ALP activity, and mineralization, demonstrating promising potential for bone tissue engineering applications. Full article

Background/Objectives: Color vision deficiency (CVD) arises from the absence or dysfunction of one or more cone photoreceptors in the retina, resulting in impaired color discrimination. Although inherited CVD cannot be cured, optical compensation strategies such as color-filtering glasses have been developed to enhance color perception. However, quantitative clinical evaluations of their corrective efficacy remain limited. This study aimed to assess the effectiveness of notch filter-based color blind glasses in improving color perception and discrimination in individuals with CVD. Methods: Notch filters were employed as color correction lenses, and clinical assessments were conducted to evaluate their impact on human color perception. Subjects underwent standardized color vision tests, including the Color Bridge test, Farnsworth-Munsell 100 Hue test, and D-15 panel test, both before and after wearing the glasses. Outcomes were quantitatively analyzed using total error score (TES), confusion angle, and confusion index (C-index) to determine changes in color discrimination performance. Results: Quantitative analysis demonstrated that wearing the notch filter glasses amplified color differences along confusion lines. In clinical trials, 83% of subjects showed improved color discrimination in the F-M 100 Hue test, with TES reductions between 6.67% and 50.00%. Furthermore, D-15 panel testing revealed that 67% of participants exhibited a decreased C-index and reduced scatter index (S-index), with specific cases shifting from deficient to normal color perception (C-index < 1.6). These results indicate that the filters effectively mitigate symptoms of color vision deficiency by increasing perceptual contrast. Conclusions: Notch filter-based color correction glasses can enhance chromatic discrimination in individuals with CVD by increasing perceptual color contrast. These findings provide practical insights for the optimization and fabrication of color vision correction eyewear utilizing spectral notch filtering strategies. Full article

The depletion of natural river sand resources in the construction industry and the pollution caused by iron tailings storage in the steel industry are the two major challenges currently faced. The use of iron tailings in construction materials is widely regarded as one of the most sustainable and cost-effective approaches. Based on C30 concrete, 12 steel tube iron tailings sand (IOT) concrete columns with different IOT substitution rates were designed and fabricated in this paper, and axial compression test research was conducted on them; finite element simulations were conducted for comparison with the experimental results, focusing on the influences of IOT substitution rate (0–100%), steel pipe wall thickness (1–4 mm), and steel strength (Q235, Q355, Q390, Q420, Q460) on the bearing capacity of concreted steel tube columns were parametrically analyzed. By comparing the calculation methods of the bearing capacity of concrete-filled steel tube columns in five relevant standards, the calculation formula for the bearing capacity of IOT columns was corrected and obtained. The results show that the failure mode of the IOT column is similar to that of the ordinary column, and the steel tube wall has all undergone circumferential band shear buckling. As the replacement ratio of IOT increases, the load-bearing capacity of columns initially improves and then declines. The finite element analysis results show that the bearing capacity of the IOT column is directly proportional to the wall thickness of the steel pipe, and increasing the wall thickness of the steel pipe can effectively improve the bearing capacity of IOT columns. The discrepancy between the predicted and experimental bearing capacities of IOT columns obtained based on the revision of the “Technical Code for Concrete-filled Steel Tube Structures” (GB 50936-2014) is within 10%, which can effectively predict the load-bearing capacity of IOT columns within a certain range. Full article

This study applies selective laser melting (SLM) to fabricate stainless steel 316L (SS316L) structures on the distribution plate of a Venturi-type nozzle in a pressurized dissolution microbubble generator. SLM is employed because the fabricated structures are approximately hundreds of micrometers in size, making them difficult to produce using conventional milling or other machining methods. These structures are designed to enhance cavitation and gas–liquid interaction, thereby enhancing microbubble generation. Various conditions of the SLM process are conducted, and the combination of 140 W laser power, 100 mm/s scan speed, 30 µm layer thickness, and 120 µm hatch distance achieves the highest relative density while maintaining the austenite phase of SS316L, thus being selected as the optimal SLM process parameters. Microbubble generation test are conducted under three different dissolution tank pressure conditions (0.20, 0.25, and 0.30 MPa) using nozzles with and without the SLM structures. The generated microbubbles in both nozzles ranges from 1 to 110 µm, satisfying the size conditions for microbubbles. The average microbubble size is smaller in the SLM-assisted nozzle (31.8 µm) compared with the plain nozzle (38.8 µm). Furthermore, under the dissolution tank pressure of 0.30 MPa for 30 s, the SLM-assisted nozzle generates a maximum of 52,368 microbubbles, representing approximately a 102.1% increase compared with the plain nozzle (25,907 microbubbles). These results demonstrate that incorporating SLM structures to Venturi-type nozzle effectively enhances microbubble generation, offering promising potential for applications in water treatment, biomedical processes, and chemical engineering. Full article

Solid-contact ion-selective electrodes (SC-ISEs) are typically constructed using ion-selective membrane (ISM)-based configurations. However, such structures often suffer from water-layer formation and the weak mechanical stability of the ISM. Herein, we report an ISM-free K⁺-SC-ISE based on a Prussian blue analogue transducer, KMnFe(CN)₆, eliminating the need for a conventional ionophore-based ISM layer. KMnFe(CN)₆ was synthesized via a one-step citrate-assisted co-precipitation method. The material functions as a bifunctional transducer, in which the open framework structure with ion-transport channels enables selective K⁺ recognition, while the redox-active Mn centers facilitate ion-to-electron transduction. The fabricated KMnFe(CN)₆-based K⁺ sensor exhibits a near-Nernstian response with a sensitivity of 52.3 ± 1.0 mV dec⁻¹ and a rapid response time of 25 s. The linear range and limit of detection were determined to 10⁻⁴ to 10⁻¹ M and 5.8 × 10⁻⁵ M, respectively. The sensor also demonstrates selectivity to representative interfering ions, with log K_ij of −2.39 ± 0.12 (Na⁺), −2.86 ± 0.09 (Li⁺), −3.06 ± 0.09 (Ca²⁺), −2.74 ± 0.12 (Mg²⁺) and −0.95 ± 0.08 (NH₄⁺). By eliminating the ISM layer, the water-layer effect is effectively avoided, resulting in excellent long-term stability with a potential drift of 57.2 ± 6.1 μV h⁻¹ over 7 days. The sensor was further applied to the analysis of K⁺ in real lake water samples, where the measured concentration showed good agreement with ion chromatography results. This work provides an ISM-free SC-ISE strategy for ion analysis in water environments. Full article

Aerodynamic drag is a key factor influencing performance in high-speed winter sports, and even small reductions in drag may contribute to meaningful improvements in race time. This study investigated the effects of seam position and seam-folding direction on the aerodynamic characteristics of skiwear fabrics using wind tunnel experiments with two simplified models: a cylinder model and a wing-shaped model. In the cylinder model, the seam position directly facing the airflow was defined as 0° and shifted in 30° increments, whereas in the wing-shaped model, the seam was moved rearward from the foremost point in 5 cm increments. The inward-folded portion of the seam was arranged either toward the airflow or opposite to it. Wind tunnel tests were conducted at wind speeds ranging from 40 to 120 km/h, and drag coefficients were calculated from measured drag forces. The results show that aerodynamic drag varied with seam position in both models. In the cylinder model, the lowest drag coefficient was observed at 30° from the front, whereas in the wing-shaped model, the lowest drag was obtained at the foremost seam position (0 cm). At 100 km/h, shifting the seam position from 0 cm to 5 cm increased the drag coefficient by approximately 54.5% in seam type A and 50.0% in seam type B. These findings suggest that seam position may be a potentially relevant aerodynamic design variable in skiwear research, whereas seam-folding direction appeared to be of secondary importance under the present test conditions. However, the present conclusions are restricted to simplified experimental geometries and should not be directly generalized to specific body regions or full-garment systems. Full article

With the rapid advancement of artificial intelligence and wearable technologies, the demand for soft, multifunctional electronic materials has grown substantially. Hydrogels have emerged as a promising platform due to their intrinsic softness, stretchability, and biocompatibility. Among them, cellulose-based conductive hydrogels uniquely integrate the sustainability of natural polymers with tunable electrical functionality, offering significant potential for flexible and biointegrated electronics. This review provides a comprehensive and critical perspective on the recent progress in cellulose-based conductive hydrogels. We systematically summarize key design strategies, including physical and chemical crosslinking and interpenetrating network engineering. More importantly, we present a comparative analysis of distinct conductive mechanisms, including ionic conduction, conductive polymers, metallic nanostructures, and carbon-based fillers, highlighting the inherent trade-offs among electrical conductivity, mechanical robustness, and environmental stability. Emerging applications in flexible electronics, energy storage, bioelectronics, and self-powered systems are discussed through structure–property relationships. Finally, we outline current challenges and future directions, emphasizing multifunctional integration, scalable fabrication, and long-term operational stability, thereby providing a framework for the rational design of next-generation sustainable electronic materials. Full article