This study presents a multiscale investigation of mycelium-based biocomposites produced via solid-state cultivation of Ganoderma lucidum on agro-food sidestreams. Three lignocellulosic residues, wheat bran (in two particle sizes), rice straw, and spent coffee grounds, were selected based on global availability and chemical diversity. The biocomposites were characterized to investigate how substrate composition and mycelial growth influence microstructure and macroscopic performance.

Monosaccharide analysis and scanning electron microscopy (SEM) revealed that wheat bran supported enhanced mycelial growth. Fine wheat bran-based composites exhibited compressive strengths up to 449 kPa at 30 % strain and tensile moduli of 15–25 MPa, significantly higher than expanded polystyrene (EPS), a conventional insulator. All biocomposites showed intrinsic surface hydrophobicity (water contact angles of 106–120°). Thermal analyses, including thermogravimetric analysis (TGA) and hot-plate conductivity measurement, confirmed their suitability as porous insulation. Cone calorimetry demonstrated improved fire safety in wheat bran-based composites, with reduced peak heat release rates (112–115 kW/m2).

Embodied energy and carbon footprint assessments indicated up to 89 % lower energy demand and 72 % lower CO2 emissions compared with EPS. Through multiscale characterization and direct benchmarking, this study shows how substrate selection and fungal-substrate interactions can be utilized to tailor performance. The findings provide insights into converting low-value biomass into scalable, fire-safer, and environmentally responsible insulation materials.

Wood is an attractive renewable construction material, but its inherent flammability, hygroscopicity, and poor resistance to leaching limit its broader application in fire-safe structures. This study investigates a catalytic heat treatment (CHT) approach combining ammonium dihydrogen phosphate, citric acid, oxalic acid, and glyoxal to improve durable fire retardancy and moisture resistance in poplar wood. Several formulations were screened based on weight percentage gain (WPG), equilibrium moisture content (EMC), and leach resistance (EN 84), leading to the selection of an optimized formulation (S3) for detailed characterization. Chemical fixation was confirmed by FTIR spectroscopy, revealing esterification, acetal crosslinking, and phosphorus–oxygen bonding, which remained partially intact after leaching. SEM–EDX analysis confirmed the incorporation of phosphorus within the treated wood and its partial retention after leaching. Optical microscopy demonstrated lumen filling and pronounced cell-wall bulking, consistent with reduced hygroscopicity and increased hardness. Flexural testing indicated a decrease in bending strength (26% and 36%) while elastic stiffness remained largely unchanged before leaching. Thermogravimetric analysis showed enhanced char formation and altered degradation pathways, while cone calorimetry revealed pronounced reductions in heat release rate (≈60%), smoke production (≈75%), and total heat release (≈40%), alongside increased residue yield. The limiting oxygen index increased from 24% for raw wood to 42% for treated wood. Microscopic observations of combustion residues revealed a more cohesive char structure in the treated samples. Fire dynamics simulator (FDS) modelling further demonstrated reduced compartment temperatures for treated wood. Neural network models were developed to predict carbon monoxide and smoke production rates, achieving high predictive accuracy for CO production (R² ≈ 0.96). Overall, the catalytic heat-treatment system promotes chemical fixation of phosphorus-containing species and improves fire performance while retaining a relatively simple processing route, offering a favourable balance between fire performance, durability, and processing simplicity.

Understanding and alleviating energy poverty is critical for sustainable development. This study harnesses a suite of Machine Learning (ML) algorithms to predict Multidimensional Energy Poverty Index (MEPI) and to highlight the spatial distribution of energy poverty. We assess the predictive accuracy of Random Forest (RF), Support Vector Machine (SVM), Artificial Neural Network (ANN), Multiple Linear Regression (MLR), and XGBoost models. The RF model outperforms others, achieving an R2 value of 0.92 and a Pearson Correlation Coefficient (PCC) of 0.97 on the testing dataset, indicative of a highly accurate prediction capability. XGBoost also demonstrates strong predictive power with corresponding values of 0.88 and 0.94, respectively. Our spatial analysis, revealing significant clustering of energy poverty with a Global Moran’s I value of 150.39, indicates that energy poverty is not only geographically concentrated but also intricately linked to socio-economic factors such as income levels, access to education, and nutritional status. These insights underscore the necessity of region-specific and socio-economically informed policy interventions. The results inform targeted interventions, particularly highlighting the critical roles of education and nutrition in mitigating energy poverty. The RF model’s accuracy rate of 92% on the testing set suggests that improvements in these sectors could significantly influence MEPI scores. The integration of ML and spatial analysis offers a nuanced and actionable understanding of energy poverty, paving the way for targeted, evidence-based policy formulation aimed at achieving SDG7: ensuring access to affordable, reliable, sustainable, and modern energy for all.

In high-temperature environments, rapid pore pressure buildup in cement-based concrete can cause explosive spalling, making its reduction crucial for mitigation. This study utilise high-temperature-modified graphene (MGP) powder to regulate the pore structure of cement-based materials, thereby reducing pore pressure. The effects of replacing cement with MGP at varying dosages (0, 5, 10, and 15 wt.%) on pore pressure and concrete performance were investigated, along with water absorption, hydration product, temperature gradient, and mechanical properties. While the compressive strength decreased slightly with graphene at room temperature (6.9%, 16% and 50.9% reductions at 5, 10 and 15 wt.%, respectively), the residual strength loss after 400 °C was significantly lower: 46.3%, 17.8%, and 29.0% for 5, 10, and 15 wt.% MGP, respectively, compared to 72.9% in the control group. A 10 wt.% MGP dosage with 20 μm was found to be optimal to reduce the pressure of concrete. Overall, this work provided a new application of MGP to improve the heat resistance of cement-based materials. 

In this study, the stability of nitrocellulose (NC) in the presence of triphenylamine (TPA), Akardite-II (AK-II), and N-Methyl-4-nitroaniline (MNA) was investigated through kinetic modeling and gaseous product analysis. The samples, consisting of pure NC and mixtures, were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential scanning calorimetry (DSC). The kinetic triplet was determined through iterative iso-conversional methods. The results obtained from TG-DSC revealed that the NC stabilized with TPA exhibited the highest average value of activation energy compared to those stabilized by other stabilizers. The addition of AK-II and MNA altered the decomposition mechanism of NC from the Avrami–Erofeev mechanism to the n-order model, whereas the addition of TPA did not affect the thermal decomposition of NC. FTIR results indicated satisfactory compatibility between the stabilizers and NC. The primary gaseous products of NC and its mixtures were identified under a helium atmosphere. The findings of this study provide guiding principles for the pyrolysis reaction model and storage safety of NC.

To investigate the differences in combustion and energy release characteristics of metastable intermolecular composite materials composed of aluminum alloys and polyvinylidene fluoride (PVDF) with different compositions, two types of alloys were selected: Al-Mg and Al-Si. Pure aluminum powder of the same size was also chosen for comparison. The PVDF-coated metal particle composites and the mixtures of PVDF with metal particles were prepared using electrospray (ES) and physical blending methods (PM), respectively. A systematic study was conducted on the morphology, compositional structure, combustion performance, energy release characteristics, and thermal reactivity of the fabricated composites and their combustion products through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), combustion performance experiments, closed vessel pressure tests, and simultaneous thermogravimetric-differential scanning calorimetry (TG-DSC). The experimental results indicated that the PVDF-coated metal particles prepared by the electrospray method exhibited a distinct core-shell structure, with the metal particles in close contact with the PVDF matrix. Compared to the PM blended materials, the ES composites demonstrated superior combustion performance and energy release characteristics during combustion. Analysis of different metal fuel systems under identical preparation conditions revealed that Al-Mg and Al-Si fuels modulate the combustion and energy release properties of aluminum alloy-PVDF MICs through two distinct pathways.

Electrospun nanofibers can lower health risks linked to exposure to particulate matter pollutants. On the other hand, nonbiodegradable polymeric materials increase issues related to their disposal and the generation of hazardous microplastics. Hence, this research aims to develop a nanofibrous membrane filter composed of polyvinyl alcohol (PVA) as a biodegradable polymer, and boric acid (BA) using an electrospinning technique. This study investigates the effect of BA on fire behavior, mechanical properties, and filtration performance of the nanofiber membranes. The morphological results show that the samples containing BA have no beads on the nanofibers. Incorporating boric acid into PVA membranes can reduce peak release heat by ≈39%. Additionally, the nanofibers containing BA can offer enhanced mechanical properties of tensile strain (≈3.6%) and Young's modulus (up to ≈45%). The optimized BA/PVA nanofibers can also demonstrate superior filtration efficiency (above 99.9% for 300 nm particles) and a low-pressure drop (150 Pa at 5.3 cm s−1 airflow velocity). Therefore, PVA nanofibers containing BA can improve not only the fire behavior than those of pure PVA nanofibers, but also increase mechanical properties, and filtration performance.

Fillers such as fly ash, slag, and biochar offer potential solutions for addressing carbon emissions from cement manufacturing and improving waste management. However, concrete with fillers experiences severe thermal damage at elevated temperatures due to issues like thermal incompatibility, pore pressure build-up, thermal stress, and phase transformation. This paper offers a comprehensive review of how fly ash, slag, and biochar impact concrete when subjected to high temperatures. It reviews phase stability, alterations in microstructure, thermal damage, and mechanical behaviour, as well as approaches to improve concrete's fire resistance. Fly ash and slag reduce microcracks in concrete during heat exposures by consuming free portlandite (Ca (OH)2) during cement hydration, while biochar mitigates pore pressure in the matrix. However, fillers lower concrete's thermal conductivity, increasing temperature gradients and reducing fire resistance. A mix of steel and polypropylene fibers enhances fire resistance more effectively than using a single fiber type.

Unsaturated polyester resins (UPRs) are versatile thermosetting materials available in a wide range from general-purpose (e.g., construction) to advanced (e.g., aerospace) materials. UPRs are best known for their promising mechanical and solvent-resistive properties, but they are highly flammable necessitating reinforcing with flame retardants (FRs). In this paper, composites of UPRs are ranked as of Poor, Good or Excellent, based on a comprehensive analysis made on cone calorimetry datasets applied by using Flame Retardancy Index (FRI). Moreover, mechanisms behind flame retardancy performance of UPRs are discussed. FRs used in reinforcing UPRs are generally divided into phosphorus (P), non-phosphorus (NP) and hybrid (any combination of P and/or NP) classes. Besides FRI, available UL-94 and limiting oxygen index (LOI) data were used to investigate whether or not they could correlate with the FRI-based outcomes. However, exploring an explicit correlation was not possible because of discrepancy or lack of data. The performance of FRs incorporated into UPRs for making them flame-retardant was mechanistically discussed based on analyses conducted on char residue. The charring effect along with cross-linking and catalytic effects supporting free radical scavenger mechanism were found to be the main reasons for flame retardancy enhancement of UPRs. Mechanistic insights into flame retardancy action were also discussed briefly in terms of action of FRs in gas and/or condensed phases.

As the infrastructure for piped hydrogen, including long tube trailers, urban utility tunnels, and hydrogen fuel cell vehicles, expands, the risk of hydrogen explosions increases. To enhance safety technologies and minimize accident risks, this paper presents a study where hydrogen venting tests were conducted with concentrations ranging from 30 % to 60 % in a 2.25-meter-long shock tube with an inner diameter of 70 mm. The effects of different vented areas and different vented shapes on the overpressure propagation law and flame characteristics were investigated. The results indicated that higher hydrogen concentrations increase vent flame temperature, but not pressure proportionally, with 40 % H2 producing the highest pressure peaks under all vented conditions. Smaller vented areas reduce the secondary explosion's impact on internal piping and the sensitivity of venting effectiveness to concentration. The distribution of pressure peaks on the outside of the pipe is highly dependent on the vented area. The vented shape has little effect on pressure, but has a slight effect on flame characteristics at R=2/5 or 1/5. In addition, the mechanism behind pressure peak generation during pipeline venting and a brief consequence analysis of the most hazardous scenario of secondary explosions has been provided.