Search Results (980)

In most commercial lithium-ion batteries, graphite remains the primary anode material. However, its theoretical specific capacity is only 372 mAh∙g⁻¹, which falls short of meeting the demands of high-performance electronic devices. Silicon anodes, despite boasting an ultra-high theoretical specific capacity of 4200 mAh∙g⁻¹, suffer from significant volume expansion (>300%) during cycling, leading to severe capacity fade and limiting their commercial viability. Currently, silicon-based polymer-derived ceramics have emerged as a highly promising next-generation anode material for lithium-ion batteries, thanks to their unique nano-cluster structure, tunable composition, and low volume expansion characteristics. The maximum capacity of the ceramics can exceed 1000 mAh∙g⁻¹, and their unique synthesis routes enable customization to align with diverse electrochemical application requirements. In this paper, we present the progress of silicon oxycarbide (SiOC), silicon carbonitride (SiCN), silicon boron carbonitride (SiBCN) and silicon oxycarbonitride (SiOCN) in the field of LIBs, including their synthesis, structural characteristics and electrochemical properties, etc. The mechanisms of lithium-ion storage in the Si-based anode materials are summarized as well, including the key role of free carbon in these materials. Full article

Background: Pain is a complex phenomenon characterized by unpleasant experiences with profound heterogeneity influenced by biological, psychological, and social factors. According to the National Health Interview Survey, 50.2 million U.S. adults (20.5%) experience pain on most days, with the annual cost of prescription medication for pain reaching approximately USD 17.8 billion. Theranostic pain nanomedicine therefore emerges as an attractive analgesic strategy with the potential for increased efficacy, reduced side-effects, and treatment personalization. Theranostic nanomedicine combines drug delivery and diagnostic features, allowing for real-time monitoring of analgesic efficacy in vivo using molecular imaging. However, clinical translation of these nanomedicines are challenging due to complex manufacturing methodologies, lack of standardized quality control, and potentially high costs. Quality by Design (QbD) can navigate these challenges and lead to the development of an optimal pain nanomedicine. Our lab previously reported a macrophage-targeted perfluorocarbon nanoemulsion (PFC NE) that demonstrated analgesic efficacy across multiple rodent pain models in both sexes. Here, we report PFC-free, biphasic nanoemulsions formulated with a biocompatible and non-immunogenic plant-based coconut oil loaded with a COX-2 inhibitor and a clinical-grade, indocyanine green (ICG) near-infrared fluorescent (NIRF) dye for parenteral theranostic analgesic nanomedicine. Methods: Critical process parameters and material attributes were identified through the FMECA (Failure, Modes, Effects, and Criticality Analysis) method and optimized using a 3 × 2 full-factorial design of experiments. We investigated the impact of the oil-to-surfactant ratio (w/w) with three different surfactant systems on the colloidal properties of NE. Small-scale (100 mL) batches were manufactured using sonication and microfluidization, and the final formulation was scaled up to 500 mL with microfluidization. The colloidal stability of NE was assessed using dynamic light scattering (DLS) and drug quantification was conducted through reverse-phase HPLC. An in vitro drug release study was conducted using the dialysis bag method, accompanied by HPLC quantification. The formulation was further evaluated for cell viability, cellular uptake, and COX-2 inhibition in the RAW 264.7 macrophage cell line. Results: Nanoemulsion droplet size increased with a higher oil-to-surfactant ratio (w/w) but was no significant impact by the type of surfactant system used. Thermal cycling and serum stability studies confirmed NE colloidal stability upon exposure to high and low temperatures and biological fluids. We also demonstrated the necessity of a solubilizer for long-term fluorescence stability of ICG. The nanoemulsion showed no cellular toxicity and effectively inhibited PGE2 in activated macrophages. Conclusions: To our knowledge, this is the first instance of a celecoxib-loaded theranostic platform developed using a plant-derived hydrocarbon oil, applying the QbD approach that demonstrated COX-2 inhibition. Full article

The design and adjustable properties of nanoporous materials are important for current and future technological applications, research, and development. In addition, nanoporous ferroelectric materials have the potential to achieve competitive ferroelectric, dielectric, and piezoelectric characteristics. In this work, using the phase-field model, we found that the shape of pores in barium titanite ceramics governs the formation of the ferroelectric domain structure and the switching hysteresis loop. A remanent polarization-coercive field (P_r-E_c) diagram is introduced to denote the shape of the hysteresis loops. We performed a fundamental study in understanding how the domain structures affect the properties of domain-engineered porous ferroelectrics. Simulation results show that the hysteresis loop of porous ferroelectrics can be designed by controlling the shape/orientation of the ellipse-shaped pores. Numerical simulations also verify that the dielectric/piezoelectric properties can be improved with artificially designed porous structures. These phase-field results may be useful in the development of highly performing lead-free ferroelectric/piezoelectric materials. Full article

Per- and polyfluoroalkyl substances (PFAS) are synthetically produced chemicals that are causing a major One Health crisis. These “forever chemicals” are widely distributed globally in air, water, and soil, and because they are highly mobile and extremely difficult to degrade in the environment. They cause additional health concerns in a circular bioeconomy and food system that recycles and reuses by-products and numerous types of waste materials. Uptake of PFAS by plants and food-producing animals ultimately leads to the consumption of PFAS-contaminated food that is associated with numerous adverse health and developmental effects in humans. Contaminated meat, milk, and eggs are some of the main sources of human PFAS exposure. Although there is no safe level of PFAS exposure, maximum tolerable PFAS consumption guidelines have been established for some countries. However, there is no international PFAS monitoring system, and there are no standardized international guidelines and mechanisms to prevent the consumption of PFAS-contaminated foods. Urgent action is needed to stop PFAS production except for critical uses, implementing effective water-purification treatments, preventing spreading sewage sludge on land and pastures used to produce food, and requiring marketers and manufacturers to use packaging that is free of PFAS. Full article

In comparison to shallow coal seams, deep coal seams exhibit characteristics of high temperature, pressure, and in-situ stress, leading to significant differences in reservoir properties that constrain the effective development of deep coalbed methane (CBM). This study takes the Carboniferous deep 8# coal seam in the Yulin area of Ordos basin as the research subject. Based on the test results from core drilling wells, a comprehensive analysis of the characteristics and variation patterns of coal reservoir properties and a comparative analysis of the exploration and development potential of deep CBM are conducted, aiming to provide guidance for the development of deep CBM in the Ordos basin. The research results indicate that the coal seams are primarily composed of primary structure coal, with semi-bright to bright being the dominant macroscopic coal types. The maximum vitrinite reflectance (R_o,max) ranges between 1.99% and 2.24%, the organic is type III, and the high Vitrinite content provides a substantial material basis for the generation of CBM. Longitudinally, influenced by sedimentary environment and plant types, the lower part of the coal seam exhibits higher Vitrinite content and fixed carbon (FC_ad). The pore morphology is mainly characterized by wedge-shaped/parallel plate-shaped pores and open ventilation pores, with good connectivity, which is favorable for the storage and output of CBM. Micropores (<2 nm) have the highest volume proportion, showing an increasing trend with burial depth, and due to interlayer sliding and capillary condensation, the pore size (<2 nm) distribution follows an N shape. The full-scale pore heterogeneity (fractal dimension) gradually increases with increasing buried depth. Macroscopic fractures are mostly found in bright coal bands, while microscopic fractures are more developed in Vitrinite, showing a positive correlation between fracture density and Vitrinite content. The porosity and permeability conditions of reservoirs are comparable to the Daning–Jixian block, mostly constituting oversaturated gas reservoirs with a critical depth of 2400–2600 m and a high proportion of free gas, exhibiting promising development prospects, and the middle and upper coal seams are favorable intervals. In terms of resource conditions, preservation conditions, and reservoir alterability, the development potential of CBM from the Carboniferous deep 8# coal seam is comparable to the Linxing block but inferior to the Daning–Jixian block and Baijiahai uplift. Full article

Phosphorylated cellulose is proposed as a bio-resin for the removal of heavy metals, as a substitute for synthetic polymer-based materials. Phosphorylation is carried out using kraft pulp fibers as the cellulose source, with phosphate esters and urea as reactants to prevent significant fiber degradation. Herein, phosphorylated fibers, with three types of counterions (sodium, ammonium, or hydrogen), are used in adsorption trials involving four individual metals: nickel, copper, cadmium, and lead. The Langmuir isotherm model is applied to determine the maximum adsorption capacities at four different temperatures (10, 20, 30, and 50 °C), enabling the calculation of the Gibbs free energy (ΔG), entropy (ΔS), and enthalpy (ΔH) of adsorption. The results show that the adsorption capacity of phosphorylated fibers is equal or even higher than that of commercially available resins (1.7–2.9 vs. 2.4–2.6 mmol/g). However, the nature of the phosphate counterion plays an important role in the adsorption capacity, with the alkaline form showing a superior ion exchange capacity than the hybrid form and acid form (2.7–2.9 vs. 2.3–2.7 vs. 1.7–2.5 mmol/g). The thermodynamic analysis indicates the spontaneous (ΔG = (-)16–(-)30 kJ/mol) and endothermic nature of the adsorption process with positive changes in enthalpy (0.45–15.47 kJ/mol) and entropy (0.07–0.14 kJ/mol·K). These results confirm the high potential of phosphorylated lignocellulosic fibers for ion exchange applications, such as the removal of heavy metals from process or wastewaters. Full article

The Scalable and Expeditious Additive Manufacturing (SEAM) process is an advanced additive manufacturing (AM) technique that relies on the optimization of metal powder suspensions to achieve high-quality 3D-printed components. This study explores the critical role of dispersants in enhancing the performance of stainless steel (SS) 420 metal powder suspensions for the SEAM process by improving powder loading, recyclability, flowability, and consequent final part density. The addition of dispersant allows for increased powder contents while preserving stable rheological properties, thereby enabling higher powder loading without compromising the rheological characteristics required in the SEAM process. Previously, our team implemented a two-step printing strategy to address the segregation issues during printing. Nonetheless, the semi-cured layer was not recyclable after printing, resulting in a significant amount of waste in the SEAM process. This, in turn, leads to a considerable increase in material costs. On the other hand, the addition of a dispersant has been shown to enhance suspension stability, enabling multiple cycles of reuse. This novel approach has been demonstrated to reduce material waste and lower production costs. The enhanced flowability guarantees uniform suspension spreading, resulting in defect-free layer deposition and superior process control. Moreover, the dispersant’s ability to impede particle agglomeration and promote powder loading contributes to the attainment of a 99.33% relative density in the final sintered SS420 parts, thereby markedly enhancing their mechanical integrity. These findings demonstrate the pivotal role of dispersants in refining the SEAM process, enabling the production of high-density, cost-effective metal components with superior material utilization and process efficiency. Full article

With the ongoing development of lightweight automobiles, research on new aluminum alloys and welding technology has gained significant attention. Friction stir welding (FSW) is a solid-state joining technique for welding aluminum alloys without melting. In this study, novel squeeze-cast Al-Si-Mg-Fe-Zn alloys with different Zn contents (0, 3.4, 6.5, and 8.3 wt%) were friction stir welded (FSWed) at a translational speed of 200 mm/min and a rotational speed of 800 rpm. These parameters were chosen based on the observations of visually sound welds, defect-free and fine-grained microstructures, homogeneous secondary phase distribution, and low roughness. Zn can affect the microstructure of Al-Si-Mg-Fe-Zn alloys, including the grain size and the content of secondary phases, leading to different mechanical and corrosion behavior. Adding different Zn contents with Mg forms the various amount of MgZn₂, which has a significant strengthening effect on the alloys. Softening observed in the weld zones of the alloys with 0, 3.4, and 6.5 wt% Zn is primarily attributed to the reduction in Kernel Average Misorientation (KAM) and a decrease in the Si phase and MgZn₂. Consequently, the mechanical strengths of the FSWed joints are lower as compared to the base material. Conversely, the FSWed alloy with 8.3 wt% Zn exhibited enhanced mechanical properties, with hardness of 116.3 HV_0.2, yield strength (YS) of 184.4 MPa, ultimate tensile strength (UTS) of 226.9 MP, percent elongation (EL%) of 1.78%, and a strength coefficient exceeding 100%, indicating that the joint retains the strength of the as-cast one, due to refined grains and more uniformly dispersed secondary phases. The highest corrosion resistance of the FSWed alloy with 6.5%Zn is due to the smallest grain size and KAM, without MgZn₂ and the highest percentage of {111} texture (24.8%). Full article

Lead-free (Bi_1/2Na_1/2)(Ti_1−x(Mg_1/3Nb_2/3)_x)O₃ ceramics were synthesized using the solid-phase method, and the effects of varying (Mg_1/3Nb_2/3)⁴⁺ content, substituting for Ti⁴⁺ ions at the B-site of the BNT perovskite lattice, on piezoelectric performance were systematically investigated. The influence of sintering temperature on both piezoelectric and ferroelectric properties was also explored, revealing that sintering temperature significantly affects both the microstructure and the electrical properties of the ceramics. The results indicate that the incorporation of (Mg_1/3Nb_2/3)⁴⁺ significantly enhances the piezoelectric and ferroelectric properties of BNT ceramics. Specifically, a maximum piezoelectric constant of 91 pC/N was achieved at a sintering temperature of 1160 °C and a doping concentration of x = 0.01. By comparing the ferroelectric properties across different doping levels and sintering temperatures, this study provides valuable insights for further design and process optimization of BNT-based piezoelectric materials. Full article

The escalating threat of infectious diseases necessitates the development of diagnostic technologies that are not only rapid and sensitive but also deployable at the point of care. Electrochemical impedance spectroscopy (EIS) has emerged as a leading technique for the label-free detection of pathogens, offering a unique combination of sensitivity, non-invasiveness, and adaptability. This review provides a comprehensive overview of the design and application of EIS-based biosensors tailored for pathogen detection, focusing on critical components such as biorecognition elements, electrode materials, nanomaterial integration, and surface immobilization strategies. Special emphasis is placed on the mechanisms of signal generation under Faradaic and non-Faradaic modes and how these underpin performance characteristics such as the limit of detection, specificity, and response time. The application spectrum spans bacterial, viral, fungal, and parasitic pathogens, with case studies highlighting detection in complex matrices such as blood, saliva, food, and environmental water. Furthermore, integration with microfluidics and point-of-care systems is explored as a pathway toward real-world deployment. Emerging strategies for multiplexed detection and the utilization of novel nanomaterials underscore the dynamic evolution of the field. Key challenges—including non-specific binding, matrix effects, the inherently low ΔR_ct/decade sensitivity of impedance transduction, and long-term stability—are critically evaluated alongside recent breakthroughs. This synthesis aims to support the future development of robust, scalable, and user-friendly EIS-based pathogen biosensors with the potential to transform diagnostics across healthcare, food safety, and environmental monitoring. Full article

Conventional adhesively bonded joints, such as single-lap, curved-lap, wavy-lap, double-lap, stepped-lap, and scarf joints, are widely used for aerospace, automotive, and medical applications. These adhesively bonded joints exhibit different load transfer mechanisms and stress distributions within adhesive layers, which depend primarily on their geometries and mechanical properties of bonded materials. As such, joint geometry and material properties play a critical role in determining the capability of the joints to withstand high loads, resist fatigue, and absorb energy under impact loading. This paper investigates the effects of geometry and material dissimilarity on the performance of both conventional bonded and interlocking joints under tensile loading based on the information available in the literature. In addition, bonding and load transfer mechanisms were analysed in detail. It was found that stress concentration often occurs at free edges of the adhesive layer due to geometric discontinuities, while most of the load is carried by these regions rather than its centre. Sharp corners further intensify resulting stresses, thereby increasing the risk of joint failure. Adhesives typically resist shear loads better than peel loads, and stiffness mismatches between adherents induce an asymmetric stress distribution. Nonetheless, similar materials promote symmetric load sharing. Among conventional joints, scarf joints provide the most uniform load distribution. In interlocking joints such as dovetail, T-slot, gooseneck, and elliptical types, the outward bending of the female component under tension can lead to mechanical failure. Full article

An efficient numerical approach utilizing a variational weak form, grounded in 2D elastic theory and variational principles, is proposed for analyzing the in-plane vibrational behavior of rectangular plates resting on elastically restrained boundaries. The differential and integral operators can be discretized into matrix representations employing the differential quadrature method (DQM) and Taylor series expansion techniques. The discretization of dynamics equations stems directly from a weak formulation that circumvents the need for any transformation or discretization of higher-order derivatives encountered in the corresponding strong equations. Utilizing the matrix elementary transformation technique, the displacements of boundary and internal nodes are segregated, subsequently leading to the derivation of the generalized eigenvalue problem pertaining to the free vibration analysis of the Functionally Graded Material (FGM) rectangular plate. Furthermore, the study examines the impact of the gradient parameter, aspect ratio, and elastic constraints on the dimensionless frequency characteristics of the FGM rectangular plate. Ultimately, the modal properties of an in-plane FGM rectangular plate are investigated. Full article

Body asymmetry is often analysed in the context of low back pain (LBP). To date, research has mainly focused on the general relationships between asymmetry and pain, with less attention paid to issues related to pressure distribution and its potential impact on the occurrence of LBP. The aim of this study was to compare biomechanical parameters in people with anatomical leg length discrepancy with and without LBP to identify overloads that may lead to pain. Early detection of common abnormalities in these parameters in both groups may influence the early prevention of 0LBP in the course of LLD. Materials and methods: This study included 60 patients with diagnosed LLD, of whom 30 had LBP (group 1, NP) and 30 were pain-free (group 2, NwP). Body weight distribution during standing and walking was analysed using pedobarography. The analysis was carried out in two stages, the first being the analysis of the biomechanical parameters for the whole study population, for group 1 with LBP and group 2 without LBP, while the second stage focused on the main issue, i.e., the comparison of the group with LBP with the group without LBP. The study included standing and walking tests. Left–right pressure distribution and ground contact time were analysed. In addition, the angle of foot abduction was analysed to indirectly assess compensatory mechanisms resulting from the asymmetry. Results: The standing test showed significantly greater pressure on the longer limb (p = 0.022) in the whole study population (N = 60). When divided into groups, it was found that in those with LBP (NP = 30), the difference was not statistically significant (p = 0.359), whereas in those without pain (NwP = 30), the pressure on the longer limb was significantly greater (p = 0.002). No differences were found between the groups in the comparative analysis. The angle of foot abduction was greater than normal across the study population (N = 60), with greater values in the shorter limb (12.83° vs. 11.04°), which was close to significance (p = 0.065). The group with LBP (NP = 30) showed a similar trend, also close to statistical significance (p = 0.054), with significantly higher values of abduction angle in both legs compared to the group without LBP (NwP = 30). In the walking test, the left–right load distributions were significantly dispersed. The mean pressure on the longer limb was significantly higher in group 1 (NP = 30) (p = 0.031), whereas this difference was not statistically significant in group 2 (NwP = 30). For mean peak pressure, there were no significant differences in any of the groups tested. In addition, the mean ground contact time during gait was longer for the longer limb in the whole study population (N = 60) (938.8 ms vs. 915 ms), but again, this difference did not reach statistical significance (p = 0.305). Comparative analysis showed no differences between the groups. Conclusions: This study showed that in people with anatomical LLD, both with and without LBP, most parameters reflected marked asymmetries in peak and mean pressures and abduction angles. A prolongation of ground contact time has also been shown, and even though some parameters were not statistically significant, it is important to note the high dispersion of left–right loading, which provides information on body load asymmetries in patients with anatomical LLD. Given that there were no differences between the groups for most of the parameters, it is important for both clinical practice and further research that the abnormalities observed in both groups (NP = 30, NwP = 30) may have been a significant predictor of the development of LBP, as the abnormalities preceded the onset of pain. This should be taken into account in diagnostic and preventive measures. Full article

Nafion, while a benchmark proton exchange membrane (PEM) for fuel cells, suffers from significant performance degradation at elevated temperatures and low humidity due to dehydration and diminished mechanical stability. To address these limitations, this study investigated the development and characterization of Nafion nanocomposite membranes incorporating sulfonated silica layered materials (sSLMs). The inherent lamellar structure, high surface area, and abundant sulfonic acid functionalities of sSLMs were leveraged to synergistically enhance membrane properties. Our results demonstrate that sSLM incorporation significantly improved ion exchange capacity, water uptake, and dimensional stability, leading to superior water retention and self-diffusion at higher temperatures. Critically, the nanocomposite membranes exhibited remarkably enhanced proton conductivity, particularly under demanding conditions of 120 C and low relative humidity (i.e., 20% RH), where filler-free Nafion largely ceases to conduct. Single H₂/O₂ fuel cell tests confirmed these enhancements, with the optimal sSLM-Nafion nanocomposite membrane (N-sSLM₅) achieving a two-fold power density improvement over pristine Nafion at 120 C and 20% RH (340 mW cm⁻² vs. 117 mW cm⁻² for Nafion). These findings underscore the immense potential of sSLM as a functional filler for fabricating robust and high-performance PEMs, paving the way for the next generation of fuel cells capable of operating efficiently under more challenging environmental conditions. Full article

Brass is a proportionate copper and zinc alloy that may be mixed to achieve a variety of mechanical, electrical, and chemical characteristics. Compared to bronze, it is more pliable. Brass has a comparatively low melting point (900–940 °C; 1650–1720 °F), depending on its composition. This review explores the most recent advancements in brass alloy technology, including the addition of silicon, tin, and aluminium to improve its strength, machinability, and resistance to corrosion. Furthermore, the development of lead-free, recyclable, and low-carbon brass alloys has been fuelled by the growing demand for environmentally friendly materials. With a renewed emphasis on antibacterial qualities and wear-resistant formulations, brass alloys are also seeing increasing use in sectors like electronics, architecture, and healthcare. Additionally, new opportunities for producing custom-designed brass components have been made possible by the development of additive manufacturing. This paper provides an overview of the current and future potential of brass alloys, highlighting their originality in addressing the changing demands of modern industry and technology. Full article