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This paper proposes a new bridge reinforcement approach grounded in the technologically mature and extensively studied polymer mortar-HSSWM reinforcement technology. To verify the feasibility of this reinforcement method, this paper investigates the mechanical properties of high-strength steel wire mesh-polyurethane cement (HSSWM-PUC) composites through bond anchorage tests. The bond anchorage test of HSSWM with PUC was completed by setting wire diameter, longitudinal wire relative anchorage length, and transverse wire spacing as test variables. Some of the test results were verified by finite element analysis. The finite element model was established with the number of transverse wires, wire spacing, relative anchorage length, and wire diameter as variables. The experimental results were further studied and analyzed. The slip, ultimate load, and load-slip relationships of HSSWM and PUC under different variables were explored. Building upon this foundation, the variation rule between bond stress and slip of HSSWM-PUC composites is analyzed. Reducing the transverse wire spacing was found to increase the ability of the transverse wires to restrain the longitudinal wires. Meanwhile, with the increase of wire diameter, the bonding stress between HSSWM and PUC gradually decreases, whereas the bonding performance of PUC can be improved by appropriately reducing the ratio of adhesive powder.

This study investigates the properties and degradability of starch-based biofilms as sustainable, non-toxic, and biodegradable materials, emphasizing the effects of starch content and plasticizers on their performance. Starch biofilms are produced by casting a water solution that utilizes glycerol as a plasticizer and acetic acid as a co-plasticizer. A comprehensive analysis of the films was conducted, assessing various properties such as water absorption, swelling, water vapor transmission rate, water vapor permeability, environmental degradation, thermal decomposition, and tensile strength. The findings reveal that the addition of acetic acid significantly improves the physical properties of the starch biofilms, while the starch content predominantly influences their physical and mechanical characteristics. Notably, all film samples demonstrated excellent soil degradability, with substantial breakdown observed after just one month of burial in the soil garden. This research contributes to the field of biodegradable materials by showcasing the effectiveness of starch biofilms as an eco-friendly alternative, highlighting the role of plasticizers in enhancing their performance and confirming their environmental sustainability through rapid degradation in soil.

Phosphogypsum, as a by-product of the wet process phosphoric acid industry, is in urgent need of resource utilization due to the environmental risks caused by its massive accumulation; at the same time, the green recycling of used wind turbine blades (including glass fibers) is also a hotspot of global concern. In this study, a synergistic regenerative preparation method of environmentally friendly construction gypsum is proposed using phosphogypsum and recycled glass fibers from waste wind turbine blades as raw materials. The matrix material was prepared by mixing physically treated phosphorus building gypsum with natural building gypsum (8:2 ratio) and blended with recycled glass fibers of different lengths (0–5, 5–10, 10–15, 15–20 mm) and blending amounts (1.0%, 1.5%, 2.0%, 2.5%), and the effect on the performance of the gypsum was systematically analyzed. The results showed that the incorporation of glass fibers significantly reduced the slurry extension (maximum drop of 30 mm) and setting time (final setting time shortened by 115 s), but significantly improved the mechanical properties. The flexural strength reached 5.6 MPa when 15–20 mm glass fibers (2.0% doping) were doped, which was 51.35% higher than that of the blank control group; the compressive strength was raised to 11.3 MPa (24.17% higher) when 10–15 mm fibers (2.5% doping) were doped. The softening coefficient reached 0.67 at 15–20 mm fiber (dosing 1.5%), an enhancement of 32.37%. The microstructure shows that the glass fibers fill the pores inhibit crack extension through the bridging effect, and present a composite damage mode of fiber fracture and matrix debonding. This study provides a new way for the efficient synergistic utilization of phosphogypsum and waste wind turbine blades, with both environmental benefits and engineering application potential.

To evaluate and compare the surface roughness and optical properties in resinbased CAD/CAM materials during thermal aging. Methods: Lava Ultimate HT (3M ESPE, USA) and VITA Enamic HT (Vita Zahnfabrik, Germany) were selected for this study. Ten specimens for each group were prepared and polished. The surface roughness (Ra) and translucency (%) were measured by a 3D profilometer and spectrophotometer before and after the accelerated aging protocol (10,000 cycles, 5◦C, and 55◦C). The freeze-fracture surfaces of tested materials were observed by SEM. Results: Enamic HT had the lower surface roughness value of 82.56 ± 6.21 nm, while Ultimate HT owned the higher Ra of 125.89 ± 8.64 nm before thermal aging. Enamic HT had the lower transparency (%) of 55.02 ± 2.57, while Ultimate HT owned the higher transparency (%) of 58.89 ± 1.63 before thermal aging. Ra in tested CAD/CAM materials was greater than 0.2 μm after 10,000 thermocycles of 5/55◦C. Conclusions: The thermal aging led to a significant increase in surface roughness and a significant decrease in transparency in both CAD/CAM materials. Ultimate HT were significantly more translucent than Enamic HT before thermal aging, while Ultimate HT showed less translucent than Enamic HT after 10,000 thermocycles of 5/55◦C.

Epoxy resin (EP) can be flexibly bonded to various materials and has a wide range of applications in aerospace manufacturing. One of the most common applications is as a matrix phase in the preparation of advanced fiber composites. Therefore, it determines the mechanical properties of composites, particularly in view of the effect of differences in strength. To this end, we prepared tensile and compressive specimens of EP according to the ASTM standard and carried out quasi-static loading tests at different strain rates (0.001 to 0.1 s−1). The results show that EP has an obvious strain rate dependence, and the elastic modulus, yield strength, and plastic flow platform in tension and compression have obvious differences. Furthermore, by fitting the experimental stress-strain curves in tension, we used the power function to establish a theoretical model in terms of yield stress and elastic modulus. Subsequently, the nonlinear constitutive models in the compressive state were established based on the Sherwood-Frost model. Thus, a complete constitutive model was obtained which takes into account both tensile and compressive differences. Based on these constitutive models, the tensile and compressive mechanical behaviors obtained by parameter inversion are in good agreement with their experimental results, proving that the developed constitutive models have good theoretical prediction capability. These research results provide a reference for the practical engineering application of EP, especially for the fiber-reinforced EP composites.

Background: Neuroinflammation and oxidative stress are key features of Alzheimer’s disease (AD), offering potential targets for localized therapeutic intervention. Delivering neurotrophic factors specifically to inflamed brain regions could improve treatment efficacy while minimizing systemic exposure. Methods: We developed a reactive oxygen species (ROS)–responsive hydrogel incorporating oxidation-labile linkers to enable the on-demand release of brain-derived neurotrophic factor (BDNF). The hydrogel’s porous structure was characterized via Scanning Electron Microscopy (SEM), and drug release behavior was evaluated under oxidative and physiological conditions. Cytoprotective efficacy was tested in H2O2-treated PC12 cells. Results: The hydrogel exhibited high porosity and released BDNF rapidly in oxidative environments, with minimal release under normal conditions. It reduced intracellular ROS in stressed PC12 cells. Conclusion: This ROS-responsive hydrogel serves as a biocompatible and intelligent drug delivery system with potential for targeted oxidative stress modulation and neurotrophic support in the treatment of AD.

This paper was created within the EU Horizon project - RECICLARM - which conducted waste management research with the purpose of recycling up to 70% of Europe’s waste [1]. Our investigation focused on developing an algorithm capable of accurately classifying materials including plastic onces in categories of interest with the help of machine learning. Various types of materials and input variables have been documented and considered while prototyping and testing the intelligent classification algorithm, which resulted in a precise and efficient solution.

Treating skin injuries remains challenging due to issues like wound infections. In this study, polyvinylidene fluoride (PVDF)/polyethylene oxide (PEO)/azithromycin (AZ) composite nanofibers were prepared using electrospinning to reduce bacterial infections in skin wounds. The surface morphology, chemical structure, and hydrophilicity of the nanofibers were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and contact angle measurements, respectively. Antibacterial performance tests revealed that increasing the AZ dosage expanded the antibacterial zone, indicating improved effectiveness. Furthermore, experiments on rat skin infections showed that the PVDF/PEO/AZ membrane inhibited suppuration at S. aureus-infected wound sites. These findings demonstrate the potential of AZ-loaded PVDF/PEO nanofiber membranes as effective antibacterial dressing.

Comparing and evaluating the fracture load of different posts and composite core of root canal-treated teeth is the aim of this study. Endodontically treated teeth were restored with zirconia (ZP), prefabricated glass fiber (GFP), and carbon (CP) post systems. Single root eighty maxillary 2nd premolars were chosen, and they received endodontic therapy. Depending on the kind of length used, the teeth were randomly assigned to four groups (n = 20), each of which was then divided into two subgroups: subgroup 1/2 removed the one-half sealing material, and subgroup 2/3 removed two-thirds of the sealing material. Prefabricated glass fiber posts were used in Group I, zirconia posts were used in Group II, carbon posts were used in Group III, and direct composite resin restoration without a post was used in Group IV (control). Samples were loaded into a universal testing machine, and statistical interpretations were made. Fracture resistance was noted. The results of the fracture one-way ANOVA were used to examine the load, and then multiple comparisons with the Bonferroni test with a threshold significant value (α=0.05). The prefabricated glass fiber post group, the carbon post, the zirconia post, and the control group all had lower fracture loads than the zirconia post.

Due to their high energy dissipation properties, in recent years, composite materials based on natural resins and fibers have been increasingly used. The paper studies the vibration behavior of composite bars reinforced with chopped wheat straw and, respectively, chopped sunflower seed shells. As matrix, an epoxy resin and, respectively, a hybrid resin based on rosin were used. A mathematical model useful for the study of damped vibrations is presented. For each of the analyzed bars, the frequency and damping factor for the first natural vibration mode are experimentally determined. Based on the experimental data, a coefficient that characterizes the vibration damping capacity for each bar is determined.