Electrospun PCL/PVA core-sheath nanofibres enabling staged antibiotic and peptide delivery for diabetic foot ulcer dressings.

ABSTRACT This study investigates a sustainable high-performance cementitious composite incorporating polypropylene fibers and a high volume of ground granulated blast furnace slag (GGBFS) to reduce clinker content and environmental impact. High-volume slag systems typically exhibit delayed hydration and reduced early-age strength. To address these limitations, nano-calcium carbonate (NCC) and nano-silica (NS) were incorporated as performance-enhancing additives. Although nano-materials are widely studied in ordinary Portland cement systems, their comparative performance in high-slag fiber-reinforced cementitious composites (FRCC) remains insufficiently clarified. The influence of NS and NCC on rheological behavior and age-dependent mechanical performance was systematically evaluated under identical mixture conditions. Fresh-state properties were assessed using slump flow, while compressive strength, flexural strength, mid-span deflection, ductility index, and energy absorption were measured at 7, 28, and 90 days. Both nano-additives enhanced mechanical performance at all ages. Nano-silica demonstrated superior long-term effectiveness, increasing 90-day compressive strength by up to 24% relative to the fiber-reinforced control. However, NS reduced slump flow from 80 mm to 70 mm (12.5%), compared to 74 mm for NCC, highlighting the trade-off between mechanical enhancement and workability in low water-to-cement ratio, high-slag FRCC systems.

Mix design optimisation for concrete with alternative binders and aggregates incorporating environmental, mechanical and durability performance

Review of biodegradable materials for aquaculture nets: Environmental performance and potential to reduce marine plastic pollution.

Microstructural characteristics, mechanical performance and constitutive modelling parameters of additively manufactured copper under quasi-static and dynamic loading conditions

This study investigates the creation of eco-efficient gypsum plaster composites that integrate untreated textile waste (TW) with a hybrid experimental-computational methodology that combines machine learning (ML) prediction with multi-objective metaheuristic optimization. Prismatic specimens of 40 × 40 × 160 mm were fabricated with TW concentrations varying from 0% to 1% and water-to-plaster (W/P) ratios between 0.55 and 0.70. The composites were evaluated for rheological parameters (initial and final setting times, spreadability), durability (capillary absorption), mechanical performance (compressive strength [CS] and flexural strength [FS]), and thermal conductivity (TC). The results indicated that TW markedly affected plaster performance: a 0.75% TW addition produced the maximum compressive strength (11.67 MPa) and flexural strength (4.17 MPa), while thermal conductivity reduced from 0.20 to 0.15 W/m·K, hence improving thermal insulation. Nonetheless, workability was diminished—spreadability decreased from 210 mm to 130 mm, and initial setting time reduced from 7 to 3 min—underscoring a trade-off. A deep neural network enhanced by the Improved Grey Wolf Optimizer (DNN–IGWO) attained superior prediction accuracy (R² > 0.95), proficiently simulating nonlinear relationships between TW and W/P ratios. A genetic algorithm (GA) produced a Pareto front of 71 non-dominated solutions, optimizing strength, thermal performance, and workability. Optimal formulations were achieved at W/P ratios of 0.55–0.65 and TW levels of 0.25–1 wt%, enabling the development of high-performance, sustainable gypsum composites derived from industrial textile by-products. The findings support the incorporation of recycled textiles in construction and illustrate how data-driven optimization can inform the advancement of sustainable gypsum-based materials utilizing industrial by-products.

Mechanical Performance and Microscopic Mechanisms of Silty Clay Solidified by CaO-MgO Activated Ground Granulated Blast Furnace Slag

Performance and environmental assessment of Portland cement incorporating waste-derived ferrous sulfate as a gypsum substitute: A case study

Shape-stabilised phase change materials for reinforced concrete roof cooling: Thermophysical performance study

• Liquid-phase sintering enables UHTCMC densification at reduced temperature. • ZrSi 2 demonstrated the highest efficacy as sintering aid at 1500 °C. • Y 2 O 3 identified as the most effective additive against interface corrosion. • A local chemistry concept discriminates interfacial and matrix mechanisms. • Correlating interface thermodynamics with densification enables interface engineering. Zirconium diboride-based Ultra-High Temperature Ceramic Matrix Composites (UHTCMCs) are promising materials for aerospace applications. A major challenge in their fabrication is achieving full densification, which typically requires temperatures above 1900 °C. In this study, the liquid-phase sintering of ZrB 2 /SiC–Cf UHTCMCs was explored to reduce densification temperature through the addition of ZrSi 2 , Y 2 O 3 , or Si 3 N 4 . Both fibre-reinforced and monolithic systems were investigated. The introduction of a liquid phase enabled densification at significantly lower temperatures (1500–1700 °C), with ZrSi 2 proving the most effective additive, allowing densities of ∼ 83%, while Si 3 N 4 and Y 2 O 3 achieved ∼ 76–80% at 1700 °C. However, the liquid phase also interacted with the carbon fibres, affecting the fibre/matrix interface. Thermodynamic analyses were performed to elucidate reactions occurring at the interface during densification, introducing the concept of local chemistry to distinguish bulk matrix reactions from interfacial ones. By correlating densification temperature with the thermodynamic stability of interface reactions, valuable insights were obtained for the design and engineering of the fibre/matrix interface. The distinct behaviour of the liquid phases resulted in significantly different mechanical performances: fracture toughness increased from ∼ 7.5 MPa·m 0.5 (ZrSi 2 and Si 3 N 4 ) to ∼ 12 MPa·m 0.5 for Y 2 O 3 , while ZrSi 2 promoted the highest flexural strength (250 MPa at room temperature and 370 MPa at 1500 °C).

• Volume shrinkage of composites during drying is dominated by reduction in height. • The positive correlation between growth duration and tensile strength is limited. • Vigorous growth is not a safe indicator for strong composites. • Mycelium-bound wheat straw composites exhibit thermal conductivity of ∼ 40 mW/(m∙K) • Removal of surface mycelium can limit humidity uptake and thus thermal conductivity. Mycelium-bound composites enable circular material use by binding bio-based substrates with fungal mycelium into lightweight materials that can be recycled or composted. Optimizing material properties for specific applications depends on pairing suitable substrates and fungi. Fungal selection is often guided by growth speed without considering whether rapid vigor leads to optimal adhesion. Similarly, the influence of mycelium on key properties such as humidity uptake or thermal conductivity remains insufficiently understood. The current study characterized mycelium-bound composites from Ganoderma sessile and Trametes versicolor on green waste, wheat straw, and a mixture of wheat straw and kapok in terms of dimensional stability, humidity response, tensile strength, and thermal conductivity. A deeper understanding was gained by investigating the effects of composite orientation on shrinkage during the drying process, the influence of growth duration on mechanical performance, and the contribution of the surface mycelium on thermal conductivity. Our data revealed a strong preference for height shrinkage during drying compared to the other dimensions, which can be attributed to fiber orientation. While fast-growing fungi such as G. sessile establish adhesion quickly, they can be surpassed by slower species ( T. versicolor ) in the long run. Moreover, strong surface growth can increase humidity uptake, negatively affecting thermal insulation performance. Finally, while composites with wheat straw exhibited competitive thermal conductivities compared to conventional insulators, values for composites with green waste were around 30 % higher. Overall, our findings provide guidance for optimal material design in terms of shape, insulation performance, and stability.

Steam-cured concrete was prepared with anhydrite and the effects of steam curing temperature and duration times on the mechanical performance, hydration products and microstructure of the concrete were investigated. The study revealed that extending curing time enhanced compressive strength for concrete cured at 60 ℃, but led to strength reduction at higher temperatures (70 ℃ and 80 ℃). Steam curing accelerated hydration but rapid product formation coarsened pores, reducing the compactness of the materials. XRD analysis revealed that anhydrite participation under steam curing promoted ettringite (AFt) formation in the concrete. At 3 d hydration age, the AFt phase remained stable at lower curing temperature (60 °C and 70 °C), whereas 80 °C curing induced its decomposition. TG-DTG analysis demonstrated that extending the curing time to 7 or 8 h significantly enhanced the hydration reaction of the concrete cured at 60 °C. SEM analysis revealed that thermal damage induced microcrack formation in concrete. In specimens cured at 60 °C, hydration products partially filled these microcracks. However, as the steam curing temperature increased to 70 °C, thermal damage became more severe, producing microcracks that could not be effectively repaired. At 80 °C steam curing, the combined presence of microcracks and pores facilitated secondary delayed ettringite formation (SEF), which induced cracking and reduced compressive strength. These microcracks further served as preferential pathways for chloride ion penetration, adversely affecting concrete durability.

Stabilization and strengthening mechanisms of red sandstone cement-stabilized macadam using solid waste

Ultrafine-grained biodegradable zinc alloys with superior mechanical performance and osteo-angiogenic activity for guided bone regeneration membranes.

Mechanical performance and life-cycle carbon reduction benefits of 3D-printed permanent-formwork columns filled with low-magnesia concrete

Mechanical performance and sustainability assessment of copper slag mortar for masonry structures

Sustainable cementitious materials from bamboo leaf-derived hydrochar: Process optimization and mechanical performance

Incorporating bio-based residues into cementitious materials offers a promising pathway toward sustainable construction. This study investigates the combined effects of biochar (BC, 0–25%), fly ash (FA), and ladle furnace slag (LFS) on the fresh and hardened properties of cementitious grouts. Twenty grout mixes were designed with Portland cement (PC) replacement levels of up to 60%. Mechanical performance and durability-related properties were evaluated after 28 days of water curing and after 210 days of air curing —under sealed and unsealed conditions. Hydration kinetics and microstructural evolution were assessed using isothermal calorimetry, XRD, and TGA. The results indicate that moderate BC incorporation (≤15%) maintained acceptable workability, particularly when combined with FA. Under air curing, higher BC contents resulted in compressive strength ( f c ) reductions of up to 40% compared to the 100% PC reference. High BC dosage diluted the hydrating matrix and delayed the onset of hydration, reducing silicate reactions and f c . The kinetic differences were also reflected in the XRD data, showing differences in the intensities of the reflections rather than the type of assemblages. Sealed air curing enhanced the f c of all mixes compared to the unsealed condition (25–80%) and reduced water absorption by 15% —especially in ternary systems— by sustaining hydration and mitigating carbonation. Strength Activity Index showed that BC-containing mixes performed relatively better under air curing than water curing, benefiting from the internal curing effect of BC. Flexural strength of BC+LFS mixes reached a comparable value to the reference (≥8 MPa). FA-containing mixes reduced shrinkage (by 22% compared to 100PC) while BC-containing mixes with PC ≥60% showed limited carbonation depth (<5 mm). Overall, optimal performance was achieved in ternary blends with BC contents up to 15%, demonstrating a viable strategy to balance mechanical performance, durability, and sustainability (showing reduced embodied carbon by 68% comparted to the reference) in low-carbon cementitious grouts. • BC incorporation up to 15% in ternary grout systems provided balanced workability, strength, and low embodied carbon. • Sealed curing increased compressive strength by 25–80% compared with unsealed conditions. • BC+LFS ternary blends exhibited higher flexural performance than FA counterparts. • Strength Activity Index indicated improved performance of BC blends under air curing relative to water curing.

Direct ink writing (DIW) followed by debinding and sintering processes offers unique advantages for fabricating biodegradable porous metallic scaffolds while avoiding several key issues associated with powder bed fusion additive manufacturing. Although DIW has been successfully applied to Mg, Fe, and their alloys, Zn-based scaffolds fabricated by DIW remain largely unexplored. Here, we fabricated, for the first time, porous Zn-based scaffolds with a Zn@ZnO core-shell structure using DIW printing combined with debinding and high-temperature oxidation. Their microstructure, degradation behavior, electrochemical response, evolution of mechanical properties, and in vitro biocompatibility were systematically evaluated. Furthermore, the sintering and corrosion mechanisms of the scaffolds were analyzed. High-temperature oxidation produced ZnO shells with thicknesses of 0.5-9.2 μm and induced the formation of needle- or flake-like ZnO, enabling stable bonding among Zn@ZnO spheres. Specimens prepared at oxidation temperatures between 500 °C and 650 °C exhibited similar yield strength and elastic modulus, while the compressive strength increased significantly with higher oxidation temperatures. Throughout the 28 days of in vitro biodegradation, the mechanical properties of the scaffolds remained within the range of cancellous bone, with mass losses between 2.8% and 7.4%. During the 7-day direct culture, all specimens exhibited good cytocompatibility, as indicated by cell viabilities above 75% and elevated alkaline phosphatase (ALP) activity. Overall, this study demonstrates the great potential of DIW-fabricated Zn@ZnO scaffolds for biodegradable bone-substituting biomaterials. STATEMENT OF SIGNIFICANCE: Direct ink writing (DIW) has emerged as a promising technique for fabricating porous biodegradable metallic scaffolds due to its low energy consumption and broad material compatibility. However, the application of DIW to biodegradable Zn-based bone implants remains largely unexplored. In this study, a fabrication strategy combining DIW with high-temperature oxidation is proposed to produce porous Zn-based scaffolds with a unique Zn@ZnO core-shell architecture. Controlled oxidation enables the formation of a multiscale hierarchical pore structure and allows effective regulation of degradation behavior, mechanical performance, and cytocompatibility. This work provides insights into the DIW processing of Zn-based biodegradable metals and highlights the potential of Zn@ZnO scaffolds for biofunctional bone substitute applications.

Recyclability of polypropylene in fused granulate fabrication: Mechanical performance through multiple printing cycles