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The escalating use of fiber-reinforced composites (FRCs) in aerospace, defense, automotive, and renewable energy industries underscores the need for a comprehensive understanding of their impact resistance and damage tolerance. This review meticulously examines low-velocity impact (LVI) on FRCs, covering impact mechanics, velocity classification, energy absorption, fiber architecture, and hybridization. Emphasizing the critical importance of damage assessment, the study analyzes intricate failure mechanisms and damages induced by LVI, addressing their potential impact on composite structural attributes. The paper critically reviews parameters influencing impact resistance and damage mechanics, evaluating performance through instrumented drop-weight impact testing. Additionally, the review explores nondestructive testing methods crucial for ensuring the reliability of composite structures. The aerospace sector and other applications requiring enhanced dynamic loading characteristics stand to benefit from a deeper understanding of composite behavior under transient impact loading. Specifically focusing on woven textile-reinforced composites, which offer specific material properties and a cost-effective manufacturing route. However, their susceptibility to out-of-plane impact loading leads to various failures, including delamination and spalling, limiting their applicability in advanced scenarios where structural integrity is paramount. It discusses advanced technology like 3D weaving as reliable methods to enhance impact resistance, damage tolerance, and delamination resistance. Notably, 3D woven composites demonstrate superior through-thickness fracture toughness, eliminating delamination as a failure mode. The findings offer valuable insights for designing structures with enhanced compression after impact and through-thickness tension characteristics. Overall, this review consolidates key advancements, challenges, and future prospects in the realm of woven composite materials and their behavior under impact loading, providing a valuable resource for academics and industry professionals alike.Graphical Abstract: The escalating use of fiber-reinforced composites (FRCs) in aerospace, defense, automotive, and renewable energy industries underscores the need for a comprehensive understanding of their impact resistance and damage tolerance. This review meticulously examines low-velocity impact (LVI) on FRCs, covering impact mechanics, velocity classification, energy absorption, fiber architecture, and hybridization. Emphasizing the critical importance of damage assessment, the study analyzes intricate failure mechanisms and damages induced by LVI, addressing their potential impact on composite structural attributes. The paper critically reviews parameters influencing impact resistance and damage mechanics, evaluating performance through instrumented drop-weight impact testing. Additionally, the review explores nondestructive testing methods crucial for ensuring the reliability of composite structures. The aerospace sector and other applications requiring enhanced dynamic loading characteristics stand to benefit from a deeper understanding of composite behavior under transient impact loading. Specifically focusing on woven textile-reinforced composites, which offer specific material properties and a cost-effective manufacturing route. However, their susceptibility to out-of-plane impact loading leads to various failures, including delamination and spalling, limiting their applicability in advanced scenarios where structural integrity is paramount. It discusses advanced technology like 3D weaving as reliable methods to enhance impact resistance, damage tolerance, and delamination resistance. Notably, 3D woven composites demonstrate superior through-thickness fracture toughness, eliminating delamination as a failure mode. The findings offer valuable insights for designing structures with enhanced compression after impact and through-thickness tension characteristics. Overall, this review consolidates key advancements, challenges, and future prospects in the realm of woven composite materials and their behavior under impact loading, providing a valuable resource for academics and industry professionals alike. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymer (FRP) composites are widely used to reinforce and repair buildings due to their high strength, corrosion resistance, lightweight, and convenient of construction. The interfacial properties between FRP and the reinforced buildings play a very important role in the effective transfer of stress and largely determine the service hours of the reinforced structures. Therefore, this paper reviews the research progress on the interfacial properties of FRP reinforced concrete. First, the composition of FRP reinforcement system is introduced. EB-FRP and NSM-FRP reinforcement methods are suitable for reinforcing different buildings. Then, the influence factors of the interfacial properties are highlighted. The choice of interfacial agent, roughness of the reinforced concrete surface, temperature and environment have very important impact on the reinforcement effect. Finally, the main damage modes and failure mechanisms of the interface between FRP and the reinforced concrete are summarized. The choice of the interfacial agent determines the main failure mode. This paper provides a theoretical basis for the further research on the interface damage mechanism of FRP reinforced concrete. [ABSTRACT FROM AUTHOR]

The fashion and textile manufacturing sectors are increasingly focusing on innovative raw materials that are renewable and biodegradable. Such materials not only mitigate environmental impacts but also prevent resource depletion. Bacterial cellulose (BC) has emerged as a prime candidate, derivable from a variety of natural ingredients such as tea and coffee in addition to a sugar source in presence of the bacterial microorganisms. Numerous studies have established the potential of BC in future fashion, and some brands have already started to utilise BC as a sustainable raw material. The applications of BC ranges from basic clothing and accessories to wearable electronics. This paper discusses the scope of BC in fashion and textiles, positioning it as a sustainable alternative to conventional materials. We present a comprehensive scoping review, covering the unique properties of BC, the factors influencing its production, and its applications in textile, clothing, and footwear over the past decade. The advantages of BC in fashion are manifold: zero-waste manufacturing, reliance on renewable sources, diminished environmental pollution, and biodegradability. Furthermore, the use of BC aligns with United Nations Sustainable Development Goals 6, 7, 12, 13 and 15. However, there exist challenges pertaining to production costs, scalability, and quality, in addition to the imperative of harnessing food waste streams instead of contending for human food resources. Addressing these challenges is vital to cement BC's position as a pivotal sustainable material in future fashion. [ABSTRACT FROM AUTHOR]

In this paper, EFKA FA 4663 (EFKA) dispersant was used for the first time in the alumina slurries tert-butyl alcohol-based freeze-casting and compared to the commonly used anionic dispersant citric acid (CA). The comparison of both dispersants was analyzed at the beginning of the process at different ultra-low freezing temperatures (− 170 to − 130 °C). The monoliths obtained with EFKA presented promising properties due to its stabilization of alumina particles by both electrostatic interactions and steric impediment, a considerable improvement when compared to the CA that promotes the stabilization of alumina particles only by electrostatic interaction. The use of different dispersants, as well as the control of freezing temperature, significantly influenced the microstructural properties of the monoliths. The monoliths exhibited prismatic pore geometry with high connectivity, forming a complex pore channel with total porosity up to 64.7%, and open porosity up to 48.5%. Results confirmed that the modification of the type of dispersant led to a difference in the grain size (up to 23.1%) and pore size (up to 30.5%) obtained in the materials. The monoliths produced with EFKA dispersant presented a considerable compressive strength resistance up to 11.7 MPa due to its dispersion mechanism that provided the thickening of the walls, confirming that the type of dispersion has a strong influence on the final properties of the materials. Therefore, the type of dispersant proved to be another parameter that allows the refinement of alumina monoliths properties, highlighting the use of EFKA as a promising alternative in the system studied. [ABSTRACT FROM AUTHOR]

In this study, four ZrNxOy coatings were deposited on the surface of Ti–45Nb alloy by multi-arc ion plating technology at different N/O ratios. The effects of oxygen content on the mechanical properties, wear resistance, electrochemical corrosion and tribocorrosion properties of the coatings were investigated separately. As the increasing of O2 ratio, the hardness value decreases from 30.2 to 9.7 GPa; the Young's modulus values decrease from 322.1 to 172.2 GPa. The H/E and H3/E2 values showed a decreasing trend with the increasing O2, which indicates a gradual decrease in the load-bearing capacity of the coatings. The critical load of these coatings in scratch test ranges from 12 N, 7.2 N, 5 N to 3N. In the friction test, both the TiNb alloy and coating exhibited predominantly abrasive and adhesive wear. The relatively low wear rate of the ZrN coating demonstrated its excellent wear resistance; however, the wear-resisting property of the ZrNxOy coating gradually decreases as the oxygen content increases, and ZrO2 coating showed the poorest wear resistance. On the contrary, the higher the oxygen content, the better the electrochemical corrosion resistance, and ZrO2 coating showed the excellent corrosion resistance. The results of tribocorrosion test show that the ZrNxOy coating has better wear resistance in simulated body fluid solution compared to Ti–Nb alloys. The experimental results and design concepts of the paper can provide a better understanding of the preparation of medical titanium alloy surface functional coatings with good comprehensive performance. [ABSTRACT FROM AUTHOR]

This paper focuses on the effect of laser shock peening on the rotational bending fatigue life of S51740 stainless steel round bar specimens. The improvement of material properties by laser shock peening is investigated by combining simulation calculations and experiments. The main results are as follows: Finite element simulations yielded three sets of laser process parameters for the study (LPS-1, LSP-2, LSP-3). The fatigue test results show that laser impact strengthening can effectively improve the fatigue life of the material, and compared with the unenhanced specimens, 350% increase in fatigue life of LSP-2 specimens. EBSD analysis showed that the LSP-2 specimen performed the best. It was verified that the material properties of S51740 stainless steel were greatly improved when the laser process parameter was LSP-2. [ABSTRACT FROM AUTHOR]

The effect of the grain boundary (GB) misorientation on plastic deformation of Inconel 718 (IN718) alloy was investigated in this paper, using in-situ tensile experiment at 650 °C in combination with crystal plasticity finite element method (CPFEM). The results indicate that dislocations tend to accumulate at GBs to form stress concentration, but the degree of stress concentration does not necessarily increase with the increase of the GB misorientation. It is attributed to the slip transfer at the GBs, determined by the angle between the slip systems of the two adjacent grains. There is a significant uncertainty in the slip transfer for GB misorientation larger than 10°. However, the mαβ′SFα+SFβ\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$m_{{{\alpha \beta }}}^{\prime} \left( {{\text{SF}}_{\alpha } + {\text{SF}}_\beta } \right)$$\end{document} criterion, which is a function of the Luster and Morris mαβ′\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$m_{{{\alpha \beta }}}^{\prime}$$\end{document} combining the Schmid factors of the two slip systems with the GB misorientation, has some statistical separation significance. Slip transfer tends to appear at GB misorientation less than 30° and mαβ′SFα+SFβ>0.78\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$m_{{{\alpha \beta }}}^{\prime} \left( {{\text{SF}}_{\alpha } + {\text{SF}}_\beta } \right) > 0.78$$\end{document}. This study clarifies the mechanism of the influence of GB misorientation on IN718 microplastic deformation and provides a new strategy to study the deformation behavior of superalloys. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) metal halide perovskites feature several specific advantages over others 2D materials, such as facile wet chemical synthesis and layers exfoliation, high composition combination especially the choice of organic cations as well as 2D phase, excellent confinement for exciton. In this paper, we present a fundamental study of diaminonaphthalene lead iodide (DANPI) perovskite, a Dion–Jacobson 2D perovskite based on divalent cation organic spacer 1,5-diaminonaphthalene. We report its material synthesis, optical and structural characterization as well as DFT calculations. Hydro-iodic acid-based wet chemistry was used to prepare DANPI crystals and, by cast-capping, thin films as well. Both DANPI materials show a dominant emission peak at about 519 nm with a full width at half-maximum as small as 14 nm. This peak coincides with the absorption edge of the material at 510 nm (2.43 eV) which suggests an exciton-related recombination process. According to single-crystal X-ray diffraction measurements the crystal structure could be either monoclinic P21/c or tetragonal P4212. DFT calculations including spin–orbit coupling show that the DANPI band gap is direct, with a valence band of s-symmetry and a conduction band of p-symmetry.A dominant emission peak at about 519 nm with a full width at half-maximum as small as 14 nm.The crystal structure could be either monoclinic P21/c or tetragonal P4212.The DANPI band gap is direct, at 2.43 eV, with a valence band of s-symmetry and a conduction band of p-symmetry.Suggested Dexter electron exchange process for Wannier excitons to organic Frenkel excitons.A dominant emission peak at about 519 nm with a full width at half-maximum as small as 14 nm.The crystal structure could be either monoclinic P21/c or tetragonal P4212.The DANPI band gap is direct, at 2.43 eV, with a valence band of s-symmetry and a conduction band of p-symmetry.Suggested Dexter electron exchange process for Wannier excitons to organic Frenkel excitons.Graphical Abstract: Two-dimensional (2D) metal halide perovskites feature several specific advantages over others 2D materials, such as facile wet chemical synthesis and layers exfoliation, high composition combination especially the choice of organic cations as well as 2D phase, excellent confinement for exciton. In this paper, we present a fundamental study of diaminonaphthalene lead iodide (DANPI) perovskite, a Dion–Jacobson 2D perovskite based on divalent cation organic spacer 1,5-diaminonaphthalene. We report its material synthesis, optical and structural characterization as well as DFT calculations. Hydro-iodic acid-based wet chemistry was used to prepare DANPI crystals and, by cast-capping, thin films as well. Both DANPI materials show a dominant emission peak at about 519 nm with a full width at half-maximum as small as 14 nm. This peak coincides with the absorption edge of the material at 510 nm (2.43 eV) which suggests an exciton-related recombination process. According to single-crystal X-ray diffraction measurements the crystal structure could be either monoclinic P21/c or tetragonal P4212. DFT calculations including spin–orbit coupling show that the DANPI band gap is direct, with a valence band of s-symmetry and a conduction band of p-symmetry.A dominant emission peak at about 519 nm with a full width at half-maximum as small as 14 nm.The crystal structure could be either monoclinic P21/c or tetragonal P4212.The DANPI band gap is direct, at 2.43 eV, with a valence band of s-symmetry and a conduction band of p-symmetry.Suggested Dexter electron exchange process for Wannier excitons to organic Frenkel excitons.A dominant emission peak at about 519 nm with a full width at half-maximum as small as 14 nm.The crystal structure could be either monoclinic P21/c or tetragonal P4212.The DANPI band gap is direct, at 2.43 eV, with a valence band of s-symmetry and a conduction band of p-symmetry.Suggested Dexter electron exchange process for Wannier excitons to organic Frenkel excitons. [ABSTRACT FROM AUTHOR]

The alloy composition and sensitization behavior are crucial factors that cannot be overlooked in Al–Mg alloys. The effect of Zn addition on mechanical properties and sensitization behavior of 5083 alloy was investigated by tensile tests, weight loss experiments, and first-principles calculation in this paper. The results show that Zn can significantly improve the strength and sensitization behavior of the alloy. The tensile strength of the cold-rolled alloy increased from 459 to 498 MPa with the addition of 1.5%Zn. Furthermore, by incorporating 2.0% Zn, the mass loss of the cold-rolled alloy after sensitization at 170℃/1 h decreased from 49.3 mg·cm−2 to 19.5 mg·cm−2. First-principles calculations indicate that Mg clusters can only exist stably near grain boundaries, while Mg–Zn clusters can exist stably both within and at grain boundaries. This reduces the number of corrosive media at grain boundaries and weakens their continuity. Moreover, the energy barrier that T-phase precipitation needs to overcome during precipitation is lower than β-phase, which transforms the stabilization schedule of the alloy from 240℃/12 h without Zn to that 210℃/4 h with 2.0% Zn-containing. The synergistic effects of Zn content and sensitization on the properties of the alloy were revealed, which sheds some light for the design of the composition and processing method according to application scenarios. [ABSTRACT FROM AUTHOR]

To investigate the dynamic recrystallization (DRX) behavior of forged 42CrMoA steel during hot deformation, the hot deformation experiments of forged 42CrMoA steel under different deformation conditions (strain rate, temperature, and strain) were carried out in this paper. The hot deformation activation energy of forged 42CrMoA steel was determined to be 413627.2J·mol-1\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$413627.2\;{\text{J}}\; \cdot{\text{mol}}^{ - 1}$$\end{document}. The constitutive model and DRX kinetic model of the steel were established. Analyzing the reconstructed parent phase grains reveals that when the strain is constant, as the deformation temperature increases and the strain rate decreases, the average size and DRX volume fraction of the parent phase grains gradually increase, and the peak stress gradually decreases. When the deformation temperature and strain rate are constant, as the strain increases, the average size of the parent phase grains gradually decreases, and the volume fraction of DRX gradually increases. Based on the cellular automaton theory model and considering the influence of grain deformation on the DRX process, a cellular automaton dynamic recrystallization (T-DRX-CA) model for forged 42CrMoA steel based on topological deformation technology was established, and the microstructure evolution under different deformation conditions was simulated. The microstructure evolution under different deformation conditions was simulated, which was compared with experimental results. The results showed that the average errors between the simulated and experimental values of the average grain size of the parent phase, the volume fraction of DRX, and peak stress were all less than 8%, and the simulated results were in good agreement with the experimental values, which indicates that the established model can accurately predict the DRX behavior of the forged 42CrMoA steel in the process of hot deformation.The hot deformation behavior of forged 42CrMoA steel under different deformation conditions was investigated by a cellular automaton dynamic recrystallization (T-DRX-CA) model based on topological deformation technique. The results showed that the average errors between the simulated and experimental values of the average grain size of the parent phase, the volume fraction of DRX, and peak stress were all less than 8%, and the simulated results were in good agreement with the experimental values, which indicates that the established model can accurately predict the DRX behavior of the forged 42CrMoA steel in the process of hot deformation.Graphical abstract: To investigate the dynamic recrystallization (DRX) behavior of forged 42CrMoA steel during hot deformation, the hot deformation experiments of forged 42CrMoA steel under different deformation conditions (strain rate, temperature, and strain) were carried out in this paper. The hot deformation activation energy of forged 42CrMoA steel was determined to be 413627.2J·mol-1\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$413627.2\;{\text{J}}\; \cdot{\text{mol}}^{ - 1}$$\end{document}. The constitutive model and DRX kinetic model of the steel were established. Analyzing the reconstructed parent phase grains reveals that when the strain is constant, as the deformation temperature increases and the strain rate decreases, the average size and DRX volume fraction of the parent phase grains gradually increase, and the peak stress gradually decreases. When the deformation temperature and strain rate are constant, as the strain increases, the average size of the parent phase grains gradually decreases, and the volume fraction of DRX gradually increases. Based on the cellular automaton theory model and considering the influence of grain deformation on the DRX process, a cellular automaton dynamic recrystallization (T-DRX-CA) model for forged 42CrMoA steel based on topological deformation technology was established, and the microstructure evolution under different deformation conditions was simulated. The microstructure evolution under different deformation conditions was simulated, which was compared with experimental results. The results showed that the average errors between the simulated and experimental values of the average grain size of the parent phase, the volume fraction of DRX, and peak stress were all less than 8%, and the simulated results were in good agreement with the experimental values, which indicates that the established model can accurately predict the DRX behavior of the forged 42CrMoA steel in the process of hot deformation.The hot deformation behavior of forged 42CrMoA steel under different deformation conditions was investigated by a cellular automaton dynamic recrystallization (T-DRX-CA) model based on topological deformation technique. The results showed that the average errors between the simulated and experimental values of the average grain size of the parent phase, the volume fraction of DRX, and peak stress were all less than 8%, and the simulated results were in good agreement with the experimental values, which indicates that the established model can accurately predict the DRX behavior of the forged 42CrMoA steel in the process of hot deformation. [ABSTRACT FROM AUTHOR]

The Journal of Materials Science has awarded the 2023 William Bonfield Prize for the best review paper to "Cement hydration mechanisms through time—a review" by Elisabeth John and Barbara Lothenbach. The review examines the work of Henri Louis Le Chatelier and William Michaëlis in the late nineteenth century and proposes pathways for future research in cement hydration mechanisms. The authors provide a comprehensive review with over 150 references, making it valuable for researchers in the field. The review was chosen by Professor Bonfield, who praised its analysis and contribution to the understanding of cement and concrete technology. Honorable mentions were also given to reviews on carbon dots, biopolymer-based treatments for cultural heritage materials, and superwetting membranes for oil/water separation. The William Bonfield Prize was created to honor Professor Bonfield's contributions to the Journal of Materials Science and materials research. [Extracted from the article]

In low- to middle-income communities, the lack of affordability of conventional sanitary products during menstrual cycles can cause psychological and health issues, ultimately affecting their quality of life. It is crucial to develop alternative products that are affordable and accessible to all while also promoting menstrual health and hygiene. Super absorbent polymers (SAPs) are a vital component in current disposable sanitary pads and nappies. However, these SAPs are often non-biodegradable and non-biocompatible. Therefore, the use of eco-friendly materials for the production of SAPs is gaining popularity in the hygiene industry, as it offers a means to reduce the carbon footprint and environmental impact associated with traditional SAPs made from non-renewable petroleum-based materials. SAPs made from polysaccharides often have naturally occurring antibacterial properties, making them appealing for commercial applications in sanitary products such as sanitary pads. In addition, the move toward reusable sanitary pads with antibacterial properties can significantly reduce waste generated by single-use products and prevent the growth of bacteria, improving the safety and hygiene of the product. Furthermore, computational modeling and artificial intelligence are now important tools in SAP synthesis, providing advantages such as predicting polymer properties, rationalizing synthesis pathways, and improving quality control. These tools can reduce synthesis costs by eliminating the need for trial-and-error approaches in polymer synthesis, ultimately promoting more affordable products for end users. Overall, these advancements in polymer synthesis and material design can help to create a more sustainable industry and promote menstrual hygiene and product accessibility to those who need it most. [ABSTRACT FROM AUTHOR]

Purpose. High-fidelity mannequins are increasingly used to train the medical staff on many medical procedures. Lately, a new challenge regarding echogenic materials to build ultrasound-responding phantoms has emerged. The challenge is to find materials with a suitable combination of ultrasound velocity and consistency to the touch. Methods. Bibliographic research was performed to identify materials with promising stiffness, shape retention, and ultrasound velocity combinations. As-standardized-as-possible specimens were realized and tested using an A-mode ultrasound machine to evaluate the US velocity through them. Four differently doped silicones, five gelatin-based materials, five synthetic gelatins, and a 3D printable resin were included in the study. After being tested, the materials were monitored for 12 days to assess their durability and shape retention and tested again to evaluate the ultrasound velocity's stability. In the paper, the results of the characterization and follow-up of the materials are presented. Results. Outcomes show that gelatins are exceptional soft tissue-mimicking materials in terms of ultrasound velocity and consistency to the touch, but are poor in terms of overtime stability and therefore suitable for disposable short-term phantoms only. Doped silicones present lower ultrasound velocity compared to the reference value of 1540 m/s found in the literature, but excellent overtime stability, and shape retention properties. Values close to biological ones were also given by the Elastic 50A and by polyvinyl chloride plastisol. Conclusion. The paper gives a quantitative overview of the fidelity of both already-in-use and non-conventional materials, focusing on the ultrasound velocity value through them and their longevity in terms of macroscopically observed dehydration, shape retention, and bacterial onset. [ABSTRACT FROM AUTHOR]

Many important properties of bacterial cellulose (BC), such as moisture absorption capacity, elasticity and tensile strength, largely depend on its structure. This paper presents a study on the effect of the drying method on BC films produced by Medusomyces gisevii using two different procedures: room temperature drying (RT, (24 ± 2 °C, humidity 65 ± 1%, dried until a constant weight was reached) and freeze-drying (FD, treated at − 75 °C for 48 h). BC was synthesized using one of two different carbon sources—either glucose or sucrose. Structural differences in the obtained BC films were evaluated using atomic force microscopy (AFM), scanning electron microscopy (SEM), and X-ray diffraction. Macroscopically, the RT samples appeared semi-transparent and smooth, whereas the FD group exhibited an opaque white color and sponge-like structure. SEM examination showed denser packing of fibrils in FD samples while RT-samples displayed smaller average fiber diameter, lower surface roughness and less porosity. AFM confirmed the SEM observations and showed that the FD material exhibited a more branched structure and a higher surface roughness. The samples cultivated in a glucose-containing nutrient medium, generally displayed a straight and ordered shape of fibrils compared to the sucrose-derived BC, characterized by a rougher and wavier structure. The BC films dried under different conditions showed distinctly different crystallinity degrees, whereas the carbon source in the culture medium was found to have a relatively small effect on the BC crystallinity. [ABSTRACT FROM AUTHOR]

This paper presents the nickel–cobalt nanoprickly particles (PNi2Co3) composited with graphene nanosheets (GNs) and carbon nanotubes (CNT), prepared via the one-pot hydrothermal method (PNi2Co3/GNs/CNT), as an efficacious nonprecious metal bifunctional electrocatalyst for both oxygen evolution and reduction reactions (OER/ORR). The study employs a comprehensive methodology, incorporating cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Brunauer–Emmett–Teller (BET) analysis to characterize and assess the materials and electrochemical properties investigated in the article. The primary objective was to successfully prepare a bifunctional electrocatalyst, and the PNi2Co3/GNs/CNT material achieved this goal. It exhibited superior OER activity, durability, and resistance to crossover effects, by an overpotential (η) of 480 mV and a Tafel slope of 61 mV dec−1, significantly higher than those obtained for RuO2 nanoparticles (η = 970 mV, Tafel slope = 85 mV dec−1). A similar trend was observed for ORR, where the PNi2Co3/GNs/CNT displayed high activity with an n = 3.93, close to the activity of a Pt/C (20 wt%), commercial catalyst with n = 4. Careful analysis of the EIS results via suitable models, in conjunction with Tafel data, revealed that the enhanced activity originates mainly from two factors: (a) the large surface area of the Ni–Co nanoprickly alloy and graphene sheets, where the CNTs (as a spacer) helped graphene nanosheets to avoid restacking and decreasing the surface area, and (b) the synergistic effect between Ni–Co nanoprickly and carbon components (GNs and CNT) of the composite.Graphical abstract: This paper presents the nickel–cobalt nanoprickly particles (PNi2Co3) composited with graphene nanosheets (GNs) and carbon nanotubes (CNT), prepared via the one-pot hydrothermal method (PNi2Co3/GNs/CNT), as an efficacious nonprecious metal bifunctional electrocatalyst for both oxygen evolution and reduction reactions (OER/ORR). The study employs a comprehensive methodology, incorporating cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Brunauer–Emmett–Teller (BET) analysis to characterize and assess the materials and electrochemical properties investigated in the article. The primary objective was to successfully prepare a bifunctional electrocatalyst, and the PNi2Co3/GNs/CNT material achieved this goal. It exhibited superior OER activity, durability, and resistance to crossover effects, by an overpotential (η) of 480 mV and a Tafel slope of 61 mV dec−1, significantly higher than those obtained for RuO2 nanoparticles (η = 970 mV, Tafel slope = 85 mV dec−1). A similar trend was observed for ORR, where the PNi2Co3/GNs/CNT displayed high activity with an n = 3.93, close to the activity of a Pt/C (20 wt%), commercial catalyst with n = 4. Careful analysis of the EIS results via suitable models, in conjunction with Tafel data, revealed that the enhanced activity originates mainly from two factors: (a) the large surface area of the Ni–Co nanoprickly alloy and graphene sheets, where the CNTs (as a spacer) helped graphene nanosheets to avoid restacking and decreasing the surface area, and (b) the synergistic effect between Ni–Co nanoprickly and carbon components (GNs and CNT) of the composite. [ABSTRACT FROM AUTHOR]

With the continuous downsizing of solder joints, the influence of the grain characteristics of the under bump metallization (UBMs) on the interfacial reaction is exposed. In this paper, the effect of grain characteristics of Cu UBM on the growth of interfacial intermetallic compounds and the formation of Kirkendall voids in Cu/Sn/Cu micro solder joints during isothermal aging at 150 °C was investigated. Electroplated polycrystalline Cu (EP-Cu), (111) single crystal Cu ((111) Cu), and (111) nano-twinned Cu ((111) nt-Cu) were selected as UBMs. After reflow soldering, the Cu6Sn5 grains formed on (111) nt-Cu were near to the orientation (21-1-3)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\text{(2}\stackrel{\mathrm{-}}{1}\stackrel{\mathrm{-}}{1}\text{3)}$$\end{document}, while those were randomly formed on both EP-Cu and (111) Cu. During isothermal aging, the Cu6Sn5 grains exhibited the highest growth rate on (111) nt-Cu UBM, and the slowest growth rate on (111) Cu UBM, due to the differing number of diffusion routes among the three Cu UBMs with distinct grain characteristics. Furthermore, no Kirkendall voids were detected on the (111) Cu UBM, however, a significant number of Kirkendall voids were identified on the (111) nt-Cu UBM, which can be attributed to the diffusion path and impurities present in the three Cu UBMs. The results will offer theoretical and practical recommendations for the selection of Cu UBMs for micro solder joints in 3D packaging interconnection technology. [ABSTRACT FROM AUTHOR]

Twinning is an important deformation mechanism for magnesium alloys, which has a significant impact on the texture evolution and mechanical properties. Pre-twinning deformation has been considered as an effective method for texture regulation. For each twinning mode, there are six crystallographically equivalent variants. Properly identifying the activated twin and understanding its variant selection criteria are essential for the development of high-performance magnesium alloys. As summarized in this paper, the observed twin variant by the commonly employed electron backscatter diffraction technique can be identified by several approaches, including misorientation analysis, trace analysis and matrix method. Schmid factor analysis was commonly performed to explain the selection of twin variants. To broaden the application scope under complex stress state, a generalized Schmid factor was derived by introducing a stress tensor. The efficiency of Schmid criteria to assess twin variant selection was confirmed to be influenced by the type of the applied stress. To consider the local effect on twin activation, in particular twin-twin transfer and slip-induced twinning, displacement gradient tensor calculation and geometrical compatibility factor analysis have been employed. It was demonstrated that local strain accommodation played a critical role in selecting the variants of cross-boundary twins in magnesium alloys. Assisted with crystal plasticity finite element modeling, the resolved shear stress on twinning and a composite Schmid factor combining the global Schmid factor and geometrical compatibility factor were obtained to better explain the activated twin variants in magnesium alloys. All the above-mentioned Schmid law based criteria and some energy based criteria as well are summarized in this paper. Their applications in evaluating twin variant selection in magnesium alloys are critically reviewed and discussed. [ABSTRACT FROM AUTHOR]

Presently, special metallic materials (titanium and a number of its alloys, stainless steels, magnesium alloys, etc.) are extensively used for the manufacturing of many medical tools and devices and choosing the appropriate material is of vital importance as it determines the success and safety of the medical devices for their application. Recent years witnessed active research and development to improve the mechanical and functional properties of these biomaterials using their nanostructuring by means of severe plastic deformation (SPD) techniques. The specific nanostructural features induced by SPD processing in metallic biomaterials significantly contribute to their performance, which has been evidenced in a series of investigative activities conducted lately to improve existing metallic biomaterials and explore potential for their production capability. This paper presents a review of these works and considers the scientific principles of achieving a higher level of properties in the metallic biomaterials as well as related challenges and uncertainties, which forms the basis for the production of a new generation of medical implants with improved design and increased biofunctionality. [ABSTRACT FROM AUTHOR]

Carbon materials have excellent thermophysical properties, and different dimensions of carbon materials are attractive candidates for enhancing high-performance aluminum matrix composites for thermal management. This paper reviews the preparation processes of carbon/aluminum composite materials in various dimensions and summarizes the main factors affecting the thermal conductivity of carbon/aluminum composites from the perspectives of metal matrix, reinforcement, and interface. Finally, we summarize the experimental progress of interfacial modification of different carbon/aluminum composites and put forward the future research direction in this field. [ABSTRACT FROM AUTHOR]

Graphical abstract: [ABSTRACT FROM AUTHOR]

In this paper, the effect of deep cryogenic treatment (DCT) on the microstructure and properties of automotive 6063 aluminum alloy at different times was investigated with automotive 6063 aluminum alloy as the research object. The results show that under the conditions of deep cryogenic treatment, the lattice distortion occurs in the alloy matrix microstructure, and the resulting internal stress promotes the large proliferation of dislocations within the alloy and the increase of dislocation density; meanwhile, after the deep cryogenic treatment, the deformed grains are transformed into recrystallized and sub-crystals structural grains, the grains are refined, and the size of the grains is refined from the original 25.2 μm to 20.3 μm, with fine equiaxed crystals. Among them, the mechanical properties of the DCT36h specimen were the best, and its hardness, tensile strength, yield strength and elongation reached 142.44 HV, 328.32 MPa, 177.42 MPa, and 29.29%, which were 34.17%, 5.62%, 11.10%, and 32.77% higher than the original sample, respectively. We believe that the main mechanism for the increase in toughness is multiple reinforcement such as dislocation strengthening, grain refinement strengthening, precipitated phase strengthening and texture strengthening. [ABSTRACT FROM AUTHOR]

Due to increased environmental awareness, the depletion of fossil fuels, and expanding ecological concerns, today’s society has a larger need for environmentally friendly materials. The idea of sustainable development of environmental material resources with enhanced economic activities was born from the rise in ecological consciousness. The textile industry generates enormous amounts of cotton waste. The environmental impact of disposing of this cotton waste makes it difficult for the textile sector to dispose of the vast amounts of produced cotton waste. As a result, all-cellulose composites (ACCs) have piqued the interest of researchers in recent years. All-cellulose composites are cellulose-based mono-component cellulose composites in which the reinforcing phase is typically composed of high-strength cellulose fibres, and the matrix is composed of regenerated cellulose. This composite type is distinguished by its exceptional interfacial compatibility and biodegradability due to the matrix and reinforcing phase having common cellulosic compositions. ACCs will become a more alluring option as enterprises prioritize sustainability and environmental responsibility because they can be recycled and reused rapidly and simply. This will contribute to less waste and enhance the overall sustainability of our society. This review paper discusses various methods to develop ACCs, textile waste-based thermoset and thermoplastic composites and textile waste-based cellulose composites (TWCCs). This review paper emphasizes approaches to develop TWCCs and the challenges and opportunities in TWCCs.Graphical Abstract: Due to increased environmental awareness, the depletion of fossil fuels, and expanding ecological concerns, today’s society has a larger need for environmentally friendly materials. The idea of sustainable development of environmental material resources with enhanced economic activities was born from the rise in ecological consciousness. The textile industry generates enormous amounts of cotton waste. The environmental impact of disposing of this cotton waste makes it difficult for the textile sector to dispose of the vast amounts of produced cotton waste. As a result, all-cellulose composites (ACCs) have piqued the interest of researchers in recent years. All-cellulose composites are cellulose-based mono-component cellulose composites in which the reinforcing phase is typically composed of high-strength cellulose fibres, and the matrix is composed of regenerated cellulose. This composite type is distinguished by its exceptional interfacial compatibility and biodegradability due to the matrix and reinforcing phase having common cellulosic compositions. ACCs will become a more alluring option as enterprises prioritize sustainability and environmental responsibility because they can be recycled and reused rapidly and simply. This will contribute to less waste and enhance the overall sustainability of our society. This review paper discusses various methods to develop ACCs, textile waste-based thermoset and thermoplastic composites and textile waste-based cellulose composites (TWCCs). This review paper emphasizes approaches to develop TWCCs and the challenges and opportunities in TWCCs. [ABSTRACT FROM AUTHOR]

Simulation models are used to emulate real-world phenomena, and errors are inevitable in the numerical computation process. Owing to that, simulation models need to be verified and validated to ensure the models and their implementations are correct. In this paper, V&V has been done for the micro3d discrete dislocation dynamics (DDD) model by comparing simulation results with corresponding theory, including any analytical solutions, other numerical solutions and experimental data. DDD simulations are a powerful simulation methodology that can help researchers better understand the plastic behavior of crystalline materials. In this study, parametric analyses for DDD simulations parameters have been performed. In addition, simulation results are verified and validated. [ABSTRACT FROM AUTHOR]

This three-part paper lends new insight into the interpretation of internal state variable (ISV) theory and fundamentals of the behavior of thermally activated dislocation ensembles. We formally define important physical concepts undergirding ISV theory such as configurational subsystems (e.g., individual grains or phases), constrained local equilibrium, and thermally activated dislocation reactions in the context of crystal plasticity and then implement these concepts within a nonequilibrium statistical thermodynamics framework. The primal importance of the Gibbs free energy barrier to dislocation reactions within each subsystem is emphasized since the enthalpy barriers are affected by local constraint and resulting long-range and short-range athermal internal stresses acting within subsystems. Kinetic and kinematic aspects of individual dislocation reactions are defined. The role of athermal internal stresses in stabilizing the positions of dislocations between barriers is acknowledged by the formal identification of the anelastic deformation, along with its role in contributing to thermal dissipation. Thermal and configurational intrinsic entropy change that contribute to the change of Gibbs free energy as a driving force for reactions are formally introduced in the same way as in first principles methods and are based on probability of pending dislocation reactions at each step. We distinguish equilibrium thermodynamics up to the saddle point of reactions, for which change of both configurational and thermal entropy applies, from post-saddle point extended glide of dislocations, which couples with the thermal bath via dispersive phonon dynamics. We write subsystem and ensemble relations for intrinsic entropy production. The concept of "degree-of-correlation" of the enthalpy barriers of thermally activated dislocation processes is introduced at both the subsystem level and across the overall ensemble of subsystems, based on the ratio of the weighted average enthalpy barrier to the maximum (rate-limiting) enthalpy barrier. It is argued that nonequilibrium trajectories progressively move toward correlated behavior of the ensemble by virtue of internal stress redistribution among interacting subsystems that are favorable and unfavorable to reactions. The degree-of-correlation is a many-body concept involving populations of dislocations within and among various configurational subsystems. [ABSTRACT FROM AUTHOR]

With development of present energy-saving society, lightweight and green development in the automotive and aerospace industries have put forward urgent demands for heat-resistant cast aluminum alloys. Present cast aluminum alloys are of lightweight and have excellent mechanical properties when serving in ambient environment. However, when serving at temperatures of 200–300 ℃ or even higher, the alloys inevitably soften and the high-temperature mechanical properties decline rapidly, hardly meeting the requirements for high-performance equipments. This paper summarizes the development process of classic heat-resistant aluminum alloys, especially the microstructural characteristics of heat-resistant cast aluminum alloys in the past decade, and reviews the current microstructure tuning strategies of heat-resistant aluminum alloys from the aspects of intrinsic heat resistance of the second phases, phase interface modification, diffusion-controlled phase transition, grain boundary stabilization and composite material design. Finally, we propose the prospects for the future development of heat-resistant aluminum alloys.Graphical abstract: With development of present energy-saving society, lightweight and green development in the automotive and aerospace industries have put forward urgent demands for heat-resistant cast aluminum alloys. Present cast aluminum alloys are of lightweight and have excellent mechanical properties when serving in ambient environment. However, when serving at temperatures of 200–300 ℃ or even higher, the alloys inevitably soften and the high-temperature mechanical properties decline rapidly, hardly meeting the requirements for high-performance equipments. This paper summarizes the development process of classic heat-resistant aluminum alloys, especially the microstructural characteristics of heat-resistant cast aluminum alloys in the past decade, and reviews the current microstructure tuning strategies of heat-resistant aluminum alloys from the aspects of intrinsic heat resistance of the second phases, phase interface modification, diffusion-controlled phase transition, grain boundary stabilization and composite material design. Finally, we propose the prospects for the future development of heat-resistant aluminum alloys. [ABSTRACT FROM AUTHOR]

In the engine of heavy trucks, the built-in fuel filter assumes the role of “lungs”. The core of the filter, namely the fuel filter paper, acts as a filter for small impurities and separates oil and water. In order to be able to separate minute impurities from the fuel, in this study, we prepared a novel fuel oil filter paper with high efficiency and high dust holding capacity based on wet-laid forming by laminating PBT/PP two-component melt-blown nonwoven material and cellulose nanocrystals (CNC)-doped cellulose wood fiber pulp with the fiber mesh combination forming technology. The effects of the CNC mixing ratio, surface density of melt-blown nonwoven material layer, surface density of cellulose wood pulp paper layer and calendaring pressure on the pore size and filtration performance of the composite samples were investigated, and the filtration efficiency of the composite samples on the tiny impurities in the fuel were also studied. The results showed that the novel composite fuel filter paper material prepared by the combined forming technology of fibrous web had high filtration efficiency and dust holding capacity, and the filtration efficiency of the composite samples could respectively reach 99.90% and 99.52% for particles larger than 14 μm and 4 μm in diameter in the fuel. At the same time, the dust holding capacity of the composite sample can reach up to 27.63 mgcm−2. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation is a sustainable and green desalination method with great prospects for development in today’s severe water shortage problem. In this paper, a novel composite aerogel was prepared by hydrothermal method with sodium alginate (SA) and Cu2+ in the preparation process using reduced graphene oxide as photothermal material and cellulose nanofibers as substrate. The good hydrophilicity of nanocellulose makes the composite aerogel have strong capillary action and continuous water transport. The gel formed by ion exchange between SA and Cu2+ greatly improves dry and wet mechanical strength of the composite aerogel and ensures the stability of the evaporator for multiple recycling. Copper is doped by reduction of copper ion complexes and reduced graphene oxide have a synergistic effect to increase the photothermal response rate of the composite aerogel of 1.446 kg m−2 h−1 with evaporation efficiency of 84.87% under one standard solar irradiation. In addition, the purification of heavy metal ions, dye wastewater as well as acid and alkali solutions also has excellent results. It is expected that this study will provide some new ideas for the fields of seawater desalination and wastewater treatment.Graphical abstract: Solar-driven interfacial evaporation is a sustainable and green desalination method with great prospects for development in today’s severe water shortage problem. In this paper, a novel composite aerogel was prepared by hydrothermal method with sodium alginate (SA) and Cu2+ in the preparation process using reduced graphene oxide as photothermal material and cellulose nanofibers as substrate. The good hydrophilicity of nanocellulose makes the composite aerogel have strong capillary action and continuous water transport. The gel formed by ion exchange between SA and Cu2+ greatly improves dry and wet mechanical strength of the composite aerogel and ensures the stability of the evaporator for multiple recycling. Copper is doped by reduction of copper ion complexes and reduced graphene oxide have a synergistic effect to increase the photothermal response rate of the composite aerogel of 1.446 kg m−2 h−1 with evaporation efficiency of 84.87% under one standard solar irradiation. In addition, the purification of heavy metal ions, dye wastewater as well as acid and alkali solutions also has excellent results. It is expected that this study will provide some new ideas for the fields of seawater desalination and wastewater treatment. [ABSTRACT FROM AUTHOR]

Agricultural waste is an economically and environmentally beneficial precursor material for the development of activated carbon (AC) due to its low price, wide sources, and large production scale. This makes it a crucial field for agricultural waste treatment and AC development. This paper reviews the research progress of agricultural waste-based activated carbon (AWAC), including the sources and characteristics of agricultural waste, and the effects of raw material characteristics and activation conditions on the performance of AWAC. It analyzes the advantages and disadvantages of various preparation methods of AWAC. Additionally, it explains the research status of AWAC in wastewater treatment, gas adsorption, catalyst carrier, and energy carrier. Finally, this paper summarizes the advantages and limitations of using agricultural wastes as raw materials for AC, and provides a prospect for raw material development, process optimization, and application expansion, taking into account the shortcomings of current research. [ABSTRACT FROM AUTHOR]

Additive manufactured (AM) technology as a novel fabrication method provides an unprecedented ability to completely design parts freely and breaks through the limitations of traditional approaches to manufacture complex structural parts. Meanwhile, magnesium (Mg) and its alloys as the lightest structural metal materials are among the most promising materials and always catch research attention. The combination of AM and Mg alloys would certainly provide new impetus for the practical application of Mg alloys. Although the research of AM-Mg alloys has made some progress and some AM-Mg alloys with impressive properties have been developed, there are still some intractable issues that hinder the further development and application of AM-Mg alloys. This paper provides a short review of the recent progress achieved in AM-Mg alloys, with a specific focus on selective laser melting (SLM), wire-arc additive manufacturing (WAAM), and solid-state AM technologies including additive friction stir (AFS) and friction stir additive manufacturing (FSAM). The defects, microstructure, and mechanical properties of AM-Mg products are summarized based on the type of AM technique. Besides, the effect of post-treatment on macro- and microstructures of SLM-Mg and WAAM-Mg alloys is also summarized. In addition, further perspectives and potential research directions are proposed for the development of AM-Mg alloys. This review could provide insights into the development of AM-Mg alloys with enhanced mechanical properties and promote the application of AM-Mg alloys. [ABSTRACT FROM AUTHOR]

Ni-based wrought superalloys are a type of superalloy produced through casting-forging processes, and usually their high-temperature performance is strongly influenced by microstructure and deformation mechanism. The typical microstructure of Ni-based wrought superalloys after heat treatments comprises equiaxed grains, numerous annealed twins, carbides within the grain interior and/or at grain boundaries, and spherical γ′ precipitates (typically comprises around 20% of their volume). The common deformation mechanisms in Ni-based wrought superalloys mainly include anti-phase boundary formed by paired dislocations shearing γ′ phase, stacking fault formed by single dislocation shearing γ′ phase, dislocation bypassing γ′ phase (precipitation-strengthened) and dislocation entanglement, dislocation networks (solid solution strengthened). In this paper, the microstructure and deformation mechanism of tensile and creep in Ni-based wrought superalloys for Advanced ultra-supercritical (A-USC) power plants are reviewed, for the two prominent areas of current research, Ni–Fe-based wrought superalloys exhibit superior processability and cost-effectiveness compared to Ni–Co-based wrought superalloys, thereby offering a more advantageous solution. [ABSTRACT FROM AUTHOR]

The Journal of Materials Science awards the annual Robert W. Cahn Prize to recognize the best paper published in the journal each year. The winner of the 2023 Cahn Prize is a research paper titled "Molecular modelling of graphene nanoribbons on the effect of porosity and oxidation on the mechanical and thermal properties." The paper presents molecular simulation models of graphene nanoribbons and examines the impact of porosity and oxidation on their mechanical and thermal conductivity properties. The paper is well-written and provides valuable insights for researchers in this field. Two other papers were selected as runners-up for the prize. All the monthly finalists for the Cahn Prize can be downloaded for free on the journal's website. [Extracted from the article]

This paper explores the hydrothermal treatment of α-Al2O3 powders to improve the binding in ceramic parts produced via a chemical bonding of ceramic powders combining a phosphate binder and infrared (IR) curing. Alumina powders are pre-treated in hydrothermal conditions with both water and phosphoric acid solution before slurry preparation and infrared irradiation. The effects of hydrothermal treatments on the powder's chemical reactions and the composite's final microstructure are assessed upon IR irradiation. While the water treatment does not induce any chemical changes, the presence of phosphoric acid leads to the appearance of phosphate phases Al(PO3)3 and AlPO4. Hydrothermal treatments in water and in phosphoric acid solution are found to drive faster and more intense phosphate condensation reactions at lower temperatures, with a stronger effect in the presence of H3PO4 (condensation temperature of 150 °C for the H3PO4-hydrothermal treated powder compared to 165 °C for the untreated powder). This improved reactivity of hydrothermal treatment α-Al2O3 powders, especially in the presence of H3PO4, leads to a general decrease of porosity for 3D printed parts compared to untreated alumina (for both top surfaces and cross-sections). While further optimization is needed to reduce the final porosity, it is possible to rapidly print 3D parts using this method, demonstrating a possible pathway to a single-step additive manufacturing (AM) process for ceramics. [ABSTRACT FROM AUTHOR]

The application of cast magnesium alloy components is increasing in recent years, especially in the new energy automotive and transportation industries. As component application scenarios become increasingly complex, the performance of cast magnesium alloys needs to be further enhanced. Significant progress has been made in casting technology and the design of cast magnesium alloys. In addition, some new application of cast magnesium alloy components is also developed recently. This paper provides an overview of the current status of high-performance cast magnesium alloys, including the alloy design, casting techniques, control of casting defects, and applications of cast magnesium alloys. Based on the issues and challenges identified here, some future research directions on cast magnesium alloys are suggested. [ABSTRACT FROM AUTHOR]

The March 2024 issue of the Journal of Materials Science features a cover paper titled "Data-driven search for promising intercalating ions and layered materials for metal-ion batteries" by Shayani Parida and her colleagues at the University of Connecticut and EaglePicher. The paper, which falls under the "Computation & theory" Topical Collection, explores the use of density functional theory (DFT) calculations and machine-learning methods to identify alternative 2D materials and intercalating ions for high-power efficiency metal-ion batteries. The journal's Editor-in-Chief, Professor Jean-François Gohy, handled the paper, highlighting the journal's commitment to multidisciplinary research. The paper is freely accessible online, and additional details can be found in the Supplementary Information. [Extracted from the article]

The material choice for electrical contacts fundamentally governs the breaking performance, safety, and reliability of electrical switches. In recent years, amid a rapid escalation in infrastructure development, an upsurge in living standards, and advancements in scientific and technological realms, there has been a burgeoning demand for increased load capacity within power distribution systems, thereby imposing novel demands on electrical contact materials. The advent of two-dimensional graphene, with its exceptional electrical conductivity, thermal conductivity, and mechanical attributes, has piqued the interest of researchers in the electrical contact field. This has spurred further research and development into innovative graphene-enhanced electrical contact materials. This paper presents a comprehensive review of the progression made in graphene-enhanced silver-based electrical contact materials over the recent years. It particularly delves into the application of graphene in silver-based contact substances, encompassing the most recent developments in graphene-enhanced contacts, the underlying principles and processes governing arc generation and erosion, the arc-resistant mechanisms inherent to graphene-enhanced contact materials, and provides a forward-looking perspective on the potential future of graphene-based contact materials. [ABSTRACT FROM AUTHOR]

Alkali-activated materials (AAM) are crafted to address escalating environmental concerns by utilizing low-carbon industrial waste, thus satisfying the need for innovative alternatives to conventional Portland cement (PC). However, the sustainability profile and cost-effectiveness of AAM depends significantly on the choice of commercial activator, with the high carbon footprint and cost of the activator serving as significant obstacles that limit the utilization of the AAM large-scale construction projects. Some locally available agricultural or industrial alkaline wastes have been researched as activators to activate other materials for AAM preparation, fundamentally eliminating AAM's activator-related drawbacks. All-waste alkali-activated materials (AWAAM) not only solve the issue of alkaline waste disposal but also exhibit satisfactory mechanical properties, along with environmental and economic advantages. This paper provides a comprehensive overview of the current phase of cementitious materials that do not require additional commercial alkali sources and are prepared entirely from waste materials, which is AWAAM. It describes the sources of alkaline wastes, elucidates the principles of synergistic interactions between these materials, explores the enhancement of AWAAM, and evaluates the cost, environmental impacts, and ionic leaching behaviors of AWAAM. Nevertheless, numerous studies have not examined the durability, leaching of hazardous materials, and workability of AWAAM. [ABSTRACT FROM AUTHOR]

Highly integrated and high-power devices place higher demands on the heat dissipation capability of heat sink components, and graphene meets the heat dissipation requirements due to its extremely high thermal conductivity of 5300 Wm−1 K−1 and good mechanical properties. Graphene by redox is one of the most promising methods for large-scale preparation of graphene; however, the quality of graphene prepared by different reduction processes varies. Herein, this paper presents a fast and efficient reduction process. Benzene was added as a reduction aid to increase the temperature from room to 2000 °C in 30 s and complete the reduction process. By this method, we obtained graphene with low defects and high thermal conductivity. The reduction process restored the lattice destroyed by the oxidation process, and the repaired material showed a higher crystallinity with a measured ID/IG of 0.18 (Ph-rGO-0, 0.58) and in-plane thermal conductivity of 510 ± 10 Wm−1 K−1. The in-plane thermal conductivity was increased by 262 Wm−1 K−1 compared with the film without benzene addition (Ph-rGO-0), which showed better homogeneous temperature performance and heat dissipation performance in practical applications. These results show the great potential for the application of graphene films prepared by this method in the field of heat dissipation materials. [ABSTRACT FROM AUTHOR]

Y2O3 materials have been widely applicated in high temperature industry owing to its high temperature stability. However, the poor sintering behavior and thermal shock resistance limited its application. The existing studies were focused on its sintering properties, yet the increase in densification of Y2O3 materials could weaken its thermal shock resistance. Y2O3 materials with smaller closed pores were fabricated by the decomposition of Al(OH)3 and the effect of Al(OH)3 on the microstructure, mechanical properties and thermal properties of Y2O3 materials were investigated in this paper. We concluded that the migration of grain boundaries was accelerated due to the ionic radii difference and the diffusion coefficient between Y3+ and Al3+, and the diffusion coefficient of Y3+ was relatively weak while the diffusion of Al3+ was mainly dominated. The Al2O3 produced by decomposition of Al(OH)3 was active, which promoted the sintering of Y2O3 materials. Meanwhile, the porosity and pore structure of Y2O3 materials were affected by the decomposition of Al(OH)3, and the appropriate pores improved the thermal shock resistance by absorbing thermal stresses. Furthermore, it indicated that adding Al(OH)3 into Y2O3 materials had a powerful influence in balancing its sintering properties and thermal shock resistance. The sample with 3 wt% Al(OH)3 exhibited the better performance in this study, with the relative density of 93.2% and the thermal shock stability factor parameter Rst of 1.74 W m1/2. [ABSTRACT FROM AUTHOR]

In the recent years, molybdenum disulfide (MoS2) has been widely used in various optical applications. MoS2 has decent optical band gap and can be used as photocatalyst for hydrogen production applications. In this paper, we reported the synthesis of flower-like nickel (Ni)-doped MoS2. The as-prepared Ni@MoS2 has optical band gap of 1.71 eV which was lower than that of the pristine MoS2 (1.90 eV). Thus, Ni@MoS2 was further used as photocatalyst for hydrogen evolution. The effect of different dose (5, 10, 15, 20 and 25 mg) of the photocatalyst (Ni@MoS2) was also examined. The photocatalytic investigations exhibited the generation of good hydrogen production amount (2021.5 µmol g−1) with reasonable hydrogen generation rate of 404.3 µmol g−1 h−1 using 25 mg Ni@MoS2. These findings suggested that doping may significantly improve the photocatalytic hydrogen production. The proposed Ni@MoS2 also presented good stability and reusability for hydrogen production. [ABSTRACT FROM AUTHOR]

To obtain the VO2 film/CVD diamond-coated tools, the deposition process of CVD diamond coating on the VO2 film surface is investigated in this paper. Firstly, the effect of carbonization treatment on VO2 film is studied. Then, the deposition process of CVD diamond coating on the VO2 film is studied. Finally, it is studied that the change law of the VO2 film/CVD diamond coating system stresses under thermal loading. Results indicate that the CVD diamond coating can be grown on the VO2 film after carbonization and diamond seed crystal treatment. The V6C5 is the most stable material after the carbonization of the VO2 film, and it is used to connect diamond coating and VO2 film. The VO2 film/CVD diamond coating system stress undergoes a sudden change under thermal loading. After the sudden change of stress, the VO2 film/CVD diamond coating system stress is only half of the CVD diamond coating stress. The adhesion of CVD diamond coating is more than 100 N. This study can provide a new idea for the deposition of CVD diamond-coated cutting tools with high bonding performance. [ABSTRACT FROM AUTHOR]

This paper outlines a new approach to designing tunable electromagnetic (EM) graphene-based meta-surfaces using convolutional neural networks (CNNs). EM meta-surfaces have previously been used to manipulate EM waves by adjusting the local phase of subwavelength elements within the wavelength scale, resulting in a variety of intriguing devices. However, the majority of these devices have only been capable of performing a single function, making it difficult to achieve multiple functionalities in a single design. Graphene, as an active material, offers unique properties, such as tunability, making it an excellent candidate for achieving tunable meta-surfaces. The proposed procedure involves using two CNNs to design the passive structure of the graphene meta-surfaces and predict the chemical potentials required for tunable responses. The CNNs are trained using transfer learning, which significantly reduced the time required to collect the training dataset. The proposed inverse design methodology demonstrates excellent performance in designing reconfigurable EM meta-surfaces, which can be tuned to produce multiple functions, making it highly valuable for various applications. The results indicate that the proposed approach is efficient and accurate and provides a promising method for designing reconfigurable intelligent surfaces for future wireless communication systems. [ABSTRACT FROM AUTHOR]

The demolding process of electroforming technology in fabricating microstructured optical-functional thin films produces the problem of excessive bonding between the metal substrate and the metal replica, which triggers the deformation of the microstructure and the reduction of precision, and the deposition of Cr–O–C discrete nuclei at the interface can play a good role in assisting the demolding effect. In this paper, the tensile deformation of polycrystalline Cu/Ni and Cu/Cr–O–C/Ni composites is investigated using molecular dynamics methods. The results show that the Cu/Ni model produces a large number of HCP structures during stretching, with holes at the interface and a large number of Cu atoms transferring to the Ni layer. The addition of the Cr–O–C layer reduces the yield strength of the Cu/Cr–O–C/Ni model by 26.41%, and at the same time, the dislocation proliferation at the interface is reduced, and the fracture is at the centralized interface, and the fracture time is reduced by 90.8%. The higher number of Cr–O–C atoms at the interface decreases the transfer of Cu atoms to the Ni layer. The results provide a possible explanation for the Cr–O–C layer-assisted precision electrodeposition debonding. [ABSTRACT FROM AUTHOR]

High frequency fatigue behavior of near surface of turbine disk are critical for its application and operation. High frequency indentation fatigue tests of GH4169 alloy under different load amplitudes, frequencies and mean loads at small length scale were conducted, and the dependence of load amplitude, load frequency and mean load on high frequency indentation fatigue property of GH4169 alloy are discussed in this paper. Depth amplitude (ha), mean depth (hm) and depth propagation rate (dh/dN) were employed as evaluation indicators of the indentation behavior. Results show that depth amplitude is only relevant with load amplitude, while mean depth is related to all the adopted influencing factors, ranked in an ascending order as load amplitude, mean load and frequency with a ranking relation of nm1=1.4 < nm2=1.71 < nm3=2.02. Furthermore, a modified Paris law was utilized to reveal the fatigue mechanism, and found the fatigue mechanism is dominated by intrinsic mechanism under the influence of mean load and load amplitude, while for the influence of frequency, the fatigue mechanism is governed by extrinsic mechanisms. Combined with SEM results and three-dimensional morphology analysis, it can be deduced that dislocation movement mode in high frequency indentation fatigue is dislocation slip. [ABSTRACT FROM AUTHOR]

The introduction of nanotechnology in the food industry has created several opportunities for this sector. Several recent advancements in food packaging use nanotechnology to enhance the function and quality of the packaging materials. This review focuses on how various nanomaterials used in different packaging materials help in maintaining the quality and shelf life of the food product. Several applications of nanomaterials in food packaging such as the use of silver nanoparticles as powerful antibacterial agents, polymer/clay nanocomposites as high barrier packaging materials, and nanosensors were mentioned here. The advances in food nanopackaging, including improved, active, smart, and bio-based packaging, were also discussed. The bio-based packaging offers a substitute for the most widely used non-degradable polymer substances. This review paper aims to highlight some of the most recent technological developments with the use of nanotechnology in the food industry and to indicate some of the many potential future research directions. [ABSTRACT FROM AUTHOR]

Characteristics of dislocations induced by Vickers indentation in hydride vapor phase epitaxy GaN were investigated. Dislocations in a rosette pattern have a 11 2 ¯ 3 / 1 1 ¯ 00 slip system and are mobile under both electron beam and multiphoton excitation. They act as nonradiative recombination sites in the range of 370–560 nm. Dislocations in a flower pattern have a 11 2 ¯ 0 / 0001 slip system and are immobile under excitation. The straight part and loop part of dislocations in a flower pattern are radiative at 440 nm and nonradiative in the range of 370–560 nm, respectively. Dislocations in a triangular area are radiative at 386 nm. The origin of the light emitting property of the straight part in a flower pattern is discussed as the transition between partial dislocations dissociated from an a-type dislocation on (0001). Recalculated dislocation pattern size ratios are well matched with experimentally estimated ones by replacing the dislocation type in a rosette pattern described in the earlier literatures (a-type) with estimated dislocation types in this paper (c + a-type). [ABSTRACT FROM AUTHOR]

This research paper presents a technology for preparing hydrogels based exclusively on natural materials (alginate, carboxymethylcellulose and starch) as carriers of micronutrients (Cu, Mn and Zn). Experiments were performed to select the hydrogel matrix components, including a comparison of the viscosity and density of sodium alginates purchased from different manufacturers, as well as the effect of additives (carboxymethylcellulose and starch) on the swelling properties and strength of the structures. Finally, a solution containing 2 wt% alginate, 2 wt% carboxymethylcellulose and 10 wt% starch was used to prepare reproducible spherical hydrogels. The influence of hydrogel preparation methods on their sorption capacity and strength (either direct dropping into micronutrient solution or two-step, i.e., dropping into calcium chloride and later sorption in micronutrient solution) was also explored. The study revealed that the enrichment of hydrogels with micronutrients by the two-step method is slower, but the structures have better mechanical strength (Young's modulus more than 4 times higher) than those enriched by the one-step method. A series of analyses (FTIR, TGA, XRD and TEM) showed that obtained hydrogels have a semicrystalline structure, are thermally stable and mainly involve carboxylic acid groups in the enrichment process. The effectiveness of the designed hydrogel matrix for the slowed release of micronutrients has been preliminarily proven in winter wheat germination tests. The best results (12.2 cm stem length and 47.9 cm roots) were obtained for the group, where hydrogels were applied at a dose equivalent to 50% of the wheat's Cu, Mn and Zn requirements. [ABSTRACT FROM AUTHOR]

The wettability of the membrane surface is very important for the separation of oil-in-water emulsion. In this paper, the hydrophilic NH2-CAU-1 was added to the membrane surface by interfacial polymerization, which greatly improved the separation efficiency of oil-in-water emulsion. The effect of the amount of NH2-CAU-1 on the separation efficiency of TFN membrane was studied, and it was determined that TFN-1 membrane had ultra-high separation efficiency of oil-in-water emulsion (> 97.60%). TFN-1 membrane has a high underwater oil contact angle (higher than 139.53°), resulting in excellent oil adhesion resistance on the membrane surface. The universality and cycling performance of TFN-1 membrane were tested, and UWOCA had good stability under strong acid, strong base and different NaCl concentrations, and the separation efficiency did not change significantly after 8 cycles. The results show that TFN-1 membrane has excellent performance in separating oil-in-water emulsions and has broad application prospects in separating oil-in-water emulsions stabilized by surfactants. [ABSTRACT FROM AUTHOR]

The February 2024 issue of the Journal of Materials Science features a cover paper titled "Enhancing the impact property of high-entropy alloys with graphene layers: a molecular dynamics study" by Qing-Xiang Pei et al. The paper explores the use of molecular dynamics simulations to study the impact of a projectile on a high-entropy alloy (HEA) containing layers of graphene. The authors highlight the broad interest in their research, as it appeals not only to the modeling community but also to other communities interested in the materials being modeled. The paper provides valuable insights into the behavior of composite materials and includes figures illustrating the preparation of the model material and the interaction between a projectile and the HEA. The article is freely accessible through the SharedIt link provided, and the corresponding authors can be contacted for access to the data. The publisher, Springer Nature, maintains a neutral stance on jurisdictional claims and institutional affiliations. [Extracted from the article]

Calcium cobaltate (Ca3Co4O9) is an excellent thermoelectric (TE) material that can realize the mutual conversion between thermal and electrical energy based on the Seebeck effect. Compared with other ceramic TE materials, Ca3Co4O9 has the advantages of good oxidation resistance and high-temperature stability, but its electrical conductivity is low, making its TE properties insufficient. Thus, the figure of merit (ZT) of Ca3Co4O9 materials cannot meet the actual production needs, so it is necessary to modify the Ca3Co4O9 to improve its TE properties. By doping with other elements, the carrier concentration in the Ca3Co4O9 system will increase, and the phonon scattering by impurity atoms will occur, whereas the scattering of electron is rather weak. Thus, the electrical conductivity of the material increases and the thermal conductivity decreases. Therefore, the TE properties of the Ca3Co4O9 material will be improved. This paper summarizes the methods of doping with other elements to improve the TE properties of Ca3Co4O9 materials in recent years, mainly including Ca site doping, Co site doping, and Ca and Co site double doping with various elements, including alkali (earth) metals, transition metals, rare earth metals, and even main group metals and non-metals. Furthermore, the current problems and development trends of the doping modification of Ca3Co4O9 materials are discussed to provide a theoretical basis for the further development and utilization of Ca3Co4O9 TE materials. [ABSTRACT FROM AUTHOR]

ZnZrOx has been used in large quantities for the preparation of light olefins from CO2, but the relationship between structure and performance remains unclear at present. In this paper, ZnZrOx were prepared by co-precipitation method, and a series of oxides with different sizes were prepared by varying the calcination temperatures. Subsequently, these oxides were combined with SAPO-34 to create a composite bifunctional catalyst for the synthesis of light olefins by CO2 hydrogenation, in which the impact of nanocrystal size effect was examined. The catalytic performance significantly increased as the nanocrystal size reduced from 18 to 12 nm. However, when the nanocrystal size was further decreased to 8 nm, the catalytic performance decline. Characterizations revealed a gradual increase in the number of oxygen vacancies with decreasing nanocrystal size. However, the oxide with the smallest nanocrystal size, prepared by varied calcination temperatures, did not yield the optimal catalytic performance due to sintering occurring during the reaction process. The results show that the assumption that smaller nanocrystal sizes inherently equate to improved catalytic performance is not universally valid, and stability must be considered when the nanocrystal size is decreased. The bifunctional catalysts used in this paper for the prepared light olefins from CO2 in yield as high as 13.8%, which is higher than most previous reports. [ABSTRACT FROM AUTHOR]