Microneedle array platforms for drug delivery and biomarker sensing: From skin mechanics guided design to scalable manufacture for clinical utility.

Impact resistance and residual compressive strength of all-carbon fiber sandwich composite structural battery inspired by turtle carapace

Rubber-iron interface separation using liquid nitrogen for material selective recycling and its mechanism.

Steel Fiber Reinforced Self-Compacting Concrete (SFSCC) is an innovative material that integrates the self-compacting ability of SCC with the strength and durability benefits of steel fibers. This review examines the mix design, fresh and hardened properties, durability, and microstructural characteristics of SFSCC, highlighting its performance advantages and challenges. Fresh properties were assessed using slump flow, T500, L-box, V-funnel, J-ring, and U-box tests, ensuring compliance with self-compacting standards. Hardened properties were evaluated through compressive strength, split tensile strength, flexural strength, elastic modulus, bond strength, flexural toughness, and impact resistance tests. Durability was examined using ultrasonic pulse velocity (UPV), permeability, sorptivity, and sulfate resistance tests, while microstructural analysis was conducted using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Energy Dispersive Spectroscopy (EDS). Findings reveal that incorporating steel fibers enhances strength, ductility, and durability. Compressive strength increased by 10%–35%, tensile strength by 11%–113%, and flexural strength by 10%–80%, while impact resistance improved significantly, with crack impact energy increasing by up to 3433%. Durability tests indicated improved resistance to water penetration and sulfate exposure, with a 6%–59% reduction in permeability and minimal compressive strength loss of 8.6% after prolonged sulfate exposure. Microstructural analysis confirmed reduced porosity and stronger interfacial bonding, contributing to long-term performance. Despite these advantages, challenges remain in optimizing mix design, ensuring uniform fiber dispersion, and addressing long-term durability. Further research is needed to refine material composition and enhance the sustainability and structural efficiency of SFSCC in construction applications.

Dynamic impact response and energy absorption of PMI foam sandwich structures for underground mining protection

Multiscale investigation of impact resistance and energy absorption mechanisms of node-enhanced gradient lattices fabricated from Al0.5CoCrFeNi

Processing of porous SiC/cordierite composites with enhanced thermal shock resistance and negative thermal expansion

Thermal shock resistance characterization of a novel porous Cu filled Sn-3Ag-0.5Cu interconnect material for power device packaging

Shock resistance of sandwich structures: A model-based optimization design strategy under soft support condition

Theory-guided design of continuous-gradient architected materials: Trapping impact energy via impedance valley

Bionic scaled fabrics for advanced impact energy: A combined experimental and simulation study

Study on the impact resistance performance of a novel beetle-inspired structure

Molecular-level understanding of droplet rebound on nonwetting surfaces is important for controlling liquid transport and removal. In this work, molecular dynamics simulations are used to investigate the oblique impact of two unequal-sized nanodroplets on a superhydrophobic Pt surface. The effects of Weber number and inclination angle on impact morphology, spreading, rebound, and energy dissipation are systematically examined. With increasing Weber number, the impact outcome evolves from regular deposition to regular bouncing, hole bouncing, and breakup-dominated states. Increasing the inclination angle enhances tangential momentum and impact asymmetry, thereby promoting perforation and fragmentation while reducing the maximum spreading factor. An inclination-corrected scaling relation, We0.382Re0.411 sinα-0.365, better describes the spreading behavior than conventional inclination-independent correlations. Rebound analysis shows that the inclination angle regulates horizontal displacement, restitution coefficient, takeoff velocity, and contact time by altering momentum partition and asymmetric recoil. Energy analysis further indicates that although viscous dissipation increases with Weber number, its proportion relative to the initial kinetic energy decreases. More importantly, the coupling between oblique impact and droplet-size asymmetry activates a rolling-assisted rebound mode, providing an additional route for energy redistribution. These results reveal how dynamic and geometric asymmetries govern nanodroplet mobility on superhydrophobic surfaces.

Abstract This study examines the influence of Glass–Carbon and Basalt–Carbon fiber reinforcements on the mechanical performance of Polyamide 66/Polytetrafluoroethylene (PA66/PTFE) blend composites for structural applications. An 80 wt.% Polyamide 66 and 20 wt.% Polytetrafluoroethylene thermoplastic blend was selected as the matrix material for composite development. The hybrid fibers combination (10 wt. % Short Glass fibers (SGF) and 10 wt. % Short Carbon fibers (SCF)) GC and (10 wt. % each of Short Basalt fibers—SBF and Short Carbon fibers– SCF) BC composites were used as the reinforcement phases. For the fabrication process—twin screw extrusion method followed by injection molding was used. For these GC and BC hybrid composites, the mechanical behaviour was evaluated using ASTM Methods. Results showed the appreciable improvement in mechanical strength over PA66/PTFE Blend. It was noticed for the GC and BC hybrid composites, 108.76% and 92.08% increase in tensile strength, 138.82% and 104.07% in flexural strength respectively over neat blend. Further, the impact strength with notched condition was responded with 16% rise in strength for GC and 26.8% drop for BC over the blend. The hybrid composites GC and BC exhibit an increase in heat deflection temperature of 231.9 °C and 229.7 °C respectively over 62.8 °C of blend at higher load. In addition, the incorporation of hybrid fibers resulted in a reduction in the melt flow index compared to the neat blend. SEM-based fracture analysis revealed that fiber fracture, deformation at the matrix–fiber interface, and the presence of non-resin regions due to fiber overlap were some of the reasons for the composite failure.

The lunar mare region is rich in basaltic minerals, and in situ resource utilization (ISRU) is a fundamental strategy for sustainable extraterrestrial construction. However, combining electroless plating with basalt fibers for such construction leads to a significant mismatch of coefficient of thermal expansion (CTE) between the fiber substrate and metal coating. Under extreme temperature alternations, this mismatch induces interfacial thermal stress concentration, causing coating peeling and performance failure. To address this issue, this study, using commercial terrestrial basalt fiber as an analogue for lunar basaltic materials, proposes an ISRU-inspired metallized fiber composite suitable for wide-temperature-range applications. By sequential electroless nickel plating and copper electroplating on basalt fibers, a nickel-copper-coated basalt fiber fabric (BF@Ni@Cu) was successfully fabricated, exhibiting high electrical conductivity, excellent electromagnetic interference shielding effectiveness (62.59 dB), and significant joule heating performance. The Ni interlayer forms a CTE gradient transition between the basalt substrate and the outer Cu layer, mitigating interfacial thermal stress. After annealing and PDMS encapsulation, the surface reflection characteristics are effectively regulated. To verify reliability under lunar diurnal temperature variations, cold-thermal shock cycle tests simulating the lunar range (from -196 to 130 °C) are conducted. After 30 cycles, the material maintained structural integrity without cracking or peeling, successfully overcoming interfacial thermal stress concentration. Consequently, the EMI shielding and joule heating performance showed only slight degradation, demonstrating excellent temperature shock resistance. This study not only provides a fiber metallization strategy that retains high performance under extreme temperature alternations but also offers a potential technical pathway inspired by ISRU for multifunctional protection and thermal management materials in future lunar base construction, through the design concept of thermal stress alleviation and failure-mode control via a gradient interlayer.

Understanding the microscopic origin of impact sensitivity (IS) in energetic materials (EMs) requires a physically meaningful descriptor that links molecular-scale dynamic response to macroscopic behavior. In this work, molecular dynamics simulations based on a Deep potential (DeepMD) were employed to investigate the impact response of α-RDX nanocrystals under practical drop-weight-like loading conditions. An explicit atomic impactor was introduced to capture heterogeneous mechanical responses, including stress concentration, energy localization, and compression-shear coupled deformation. The simulations reveal that impact-induced reaction initiation proceeds through a sequence of impact energy deposition, mechanical compression, hotspot formation, and rapid decomposition. These processes collectively reflect the intrinsic resistance of material to impact-induced failure at the molecular scale. The decomposition fraction is used as an observable to identify the onset of irreversible reactions, from which the critical impact velocity (vc) is defined. vc serves as a molecular-level descriptor of impact sensitivity that quantifies the material resistance to impact-induced failure, providing a physically interpretable measure of impact resistance. Comparative simulations on eight energetic crystals (IS = 3.5-120 J) reproduce the experimental impact sensitivity ranking with a good correlation (R2 = 0.91) between the descriptor vc2 and IS. These results establish a direct link between atomistic failure processes and macroscopic impact sensitivity, providing a descriptor-based framework for the quantitative prediction and virtual screening of EMs with improved safety-performance balance.

The growing volume of industrial waste and the need for sustainable material solutions drive the search for cost-effective fillers and energy-efficient processing methods for polymer composites. This study investigates the valorization of brick dust (BD), a fine ceramic waste, as a reinforcing filler for unsaturated polyester resin (UPR), combined with microwave (MW) treatment applied at different stages of composite fabrication. The brick dust was comprehensively characterized using laser diffraction, SEM, EDX, XRD, and FTIR, revealing an environmentally safe aluminosilicate powder with a mean particle size of 3–6 µm, plate-like morphology, and surface hydroxyl groups favorable for matrix interaction. The optimal filler content was found to be 50 phr, which increased flexural strength by 6.5%, flexural modulus by 134%, tensile strength by 11%, and impact strength by 40% compared to neat UPR. Among the MW strategies evaluated, post-curing of the fully polymerized composite for 120 s proved most effective, yielding further improvements in flexural strength (110 MPa, +34.1%), flexural modulus (8250 MPa, +49.7%), impact strength (13.8 kJ/m2, +119%), and Shore D hardness (88). MW post-curing also increased the gel fraction from 95.0% to 97.8%, raised the thermal stability index (THRI) from 150.6 to 165.8, and reduced equilibrium water absorption from 0.62% to 0.47% with a reversibility index of 87.5%. Fracture surface analysis confirmed a transition from interfacial debonding to cohesive matrix failure, with ultra-thin polymeric veils replicating the scaly filler structure. These results demonstrate that microwave post-curing synergistically enhances the mechanical, thermal, and moisture-resistant properties of brick dust-filled polyester composites.

The automotive industry has always demanded innovation in renewable materials that are environmentally friendly. One of the natural materials that has the potential as a constituent material to make motor vehicle parts is blood clam shell waste (Anadara Granosa) which can be used as a raw material for making brake pads. This study has the purpose to analyze the effect of the addition of blood shell powder on the wear, toughness, and hardness value of epoxy resin matrix composite as a motorcycle brake pad. This study is a type of experimental research by comparing the experimental group with the control group (Honda Genuine Parts brand brake pads). The test results showed that the addition of 30% of blood shells powder got the most optimal results with a wear value of 1.27×10-6 mm2/kg, impact value 2.41×10-3 J/mm2, hardness of 19.98 kgf/mm2. The 30% variation has the closest results to the test value on the brake pads of the Honda Genuine Parts brand motorcycle. With this, it can be concluded that the more volume of blood shells powder, the more the strength of the composite increases. With these results, blood shell powder composite can be recommended as an alternative to brake pad friction material that is more environmentally friendly.

ABSTRACT Amid growing concerns about children and young people’s mental health and wellbeing, UK government policy has increasingly positioned schools and colleges as key sites for prevention and early intervention. This has been operationalised through the Whole School and College Approach (WSCA) and its eight core principles. Despite widespread adoption, limitations in national monitoring and evaluation persist. Using a mixed-methods approach, we developed the WSCA Measurement Toolkit to support systematic monitoring of WSCA implementation and outcomes. The Toolkit comprises two components. The 17-item Implementation Self-Assessment Tool (ISAT) measures how embedded each of the eight WSCA principles are and was initially piloted in 28 schools in Study 1. The Outcomes Self-Assessment Tool (OSAT) assesses 12 outcome dimensions, each rated for observed impact and evidence strength, producing weighted scores to reflect both outcome change and evidence quality. In Study 2, the Toolkit was evaluated in 19 schools to assess feasibility, acceptability, and relationship between implementation and outcomes. In Study 1, ISAT dimensions such as Ethos and environment and Universal mental health work were rated as highly embedded within WSCA practices, whereas areas including Governor engagement and Data collection were less well developed. In Study 2, higher implementation scores were associated with better outcomes, a relationship further strengthened when outcome scores were weighted by evidence quality. Participants reported the Toolkit to be feasible and acceptable to use. These findings suggest the WSCA Measurement Toolkit is a practical, acceptable tool for WSCA evaluation and highlight the importance of implementation quality for achieving positive outcomes.

Weld quality is an important parameter in ensuring the overall safety and integrity of pipelines made from high-strength steel used for the transmission of oil and natural gas. In multi-layer pipeline welding, poor heat input control can result in excessive reinforcement, lack of fusion, unsatisfactory microstructural changes, and poor mechanical properties. Hence, in the current research, the effects of Low Heat Input (LHI) and High Heat Input (HHI) on the shape, thermal behaviour, and mechanical properties of API 5L L415Q pipeline steel were analyzed via welding using the GTAW-SMAW process. The GTAW process is used for the root pass, while the SMAW process is used for the hot, fill, and cap passes. A combination of Taguchi experimental design and desirability-based multi-response optimization was used to determine the optimal values of welding current, welding voltage, welding travel speed, heat input, and reinforcement properties for individual passes. Welding parameters were verified through tensile tests, impact energy tests, hardness tests, bend tests, macroexamination, non-destructive testing, and field-scale application of the developed welding technique. Both LHI and HHI welding conditions produced welded joints that met the API pipeline welding specifications. LHI welding conditions offered better penetration consistency and a more uniform hardness distribution, since the thermal cycle was lower and the cooling rate was higher. In contrast, HHI welding conditions yielded higher impact energy in the weld metal at the fusion line and in the heat-affected zones, due to variations in the thermal cycle. The heat-input optimization strategy also resulted in reduced grain coarsening and a balanced metallurgical balance between strength and toughness. Moreover, industrial-scale validation of 250 pipeline girth welds has indicated consistent welding quality, acceptable geometry, and the absence of critical weld defects on radiographic testing.