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In the face of a threat to democratic rule, a Brazilian electoral court barred its former president, Jair Bolsonaro, from holding office for eight years. Unfortunately, the United States lacks a similar electoral court to protect the integrity of the electoral process—in fact, our electoral system is organized in such a way that it invites attacks on its integrity. These problems in design can be traced back to the US Constitution, which, notwithstanding its durability and historical greatness, suffers from certain defects that leave the United States vulnerable to democratic back-sliding. Principal defects include the method of presidential elections via the Electoral College, the two-senator-per-state rule in the upper chamber of Congress, and, perhaps most damaging of all, the method for amending the Constitution. [ABSTRACT FROM AUTHOR]

Purpose: To describe and compare the race characteristics, demands, and durability profile of a male and a female Grand Tour winner. Methods: Overall and stage-type-specific (ie, time trials, flat, semimountainous, and mountain) demands and race characteristics during 2 Grand Tours were determined and compared between the female and male cyclists. In addition, relative power output distribution and pacing, percentage of functional threshold power (FTP), and changes in maximal mean power outputs (MMPs) with increasing levels of kilojoules burned were determined. Results: Although many differences were found between course and absolute racing demands between the male (FTP: 413 W; critical power: 417 W) and female (FTP: 297 W; critical power: 297 W) cyclists, similar power distributions and pacing strategies were found if data were expressed relatively. However, the female cyclist rode a higher percentage of her FTP during the first 2 quarters of flat stages (14.7%–15.1%) and the last quarter of mountain stages (9.8%) than the male cyclist. Decrements in MMPs were only observed after burning 30 kJ·kg−1 in the female and 45 kJ·kg−1 in the male Grand Tour winner. Conclusions: Both the male and female Grand Tour winners produced very high 20- to 60-minute MMPs, whereas decrements in MMPs were only observed after having burned 75% (female) and 80% (male) of total kilojoules burned during a stage. These are the latest and lowest in MMPs reported in the scientific literature and highlight the importance of durability in combination with excellent climbing and time-trial skills, which are needed to be able to win a Grand Tour. [ABSTRACT FROM AUTHOR]

Green hydrogen, produced via water electrolysis using renewable electricity, will play a crucial role in decarbonizing industrial and heavy-duty transportation sectors. Anion exchange membrane water electrolyzers (AEMWEs) can overcome many of the performance and cost limitations of incumbent technologies, however, still suffer from durability challenges due to oxidative instability of anion-exchange ionomers. Herein, the use of an electro-active porous transport layer as anode (PTL-electrode) is demonstrated to enable efficient and durable AEMWEs. The stainless-steel PTL-electrodes are shown to have superior performance and durability compared to traditional catalyst layers containing ionomer and nanoparticle catalysts. An AEMWE cell operating at 2 A cm−2 for over 600 h exhibited a degradation rate of just 5 µV h−1. During operation, the surface composition of the stainless steel transforms into a mixture of iron and nickel oxyhydroxides, contributing to enhanced oxygen-evolution reaction activity. The combination of experimental work and modeling elucidates how the bulk structure of the PTL-electrode offers an additional design dimension to further improve electrolyzer performance. Lastly, a surface modification strategy is applied to a PTL-electrode to achieve an even higher performing AEMWE (2.3 vs 2.0 A cm−2 at 1.8 V). Overall, this work lays out pathways toward more efficient, durable, and affordable AEMWEs.

Heat exchangers are made of metals because of their high heat conductivity and mechanical stability. Metal surfaces are inherently hydrophilic, leading to inefficient filmwise condensation. It is still a challenge to coat these metal surfaces with a durable, robust, and thin hydrophobic layer, which is required for efficient dropwise condensation. Here, we report the nonstructured and ultrathin (∼6 nm) polydimethylsiloxane (PDMS) brushes on copper that sustain high-performing dropwise condensation in high supersaturation. Due to the flexible hydrophobic siloxane polymer chains, the coating has low resistance to drop sliding and excellent chemical stability. The PDMS brushes can sustain dropwise condensation for up to ∼8 h during exposure to 111 °C saturated steam flowing at 3 m·s-1, with a 5-7 times higher heat transfer coefficient compared to filmwise condensation. The surface is self-cleaning and can reduce the level of bacterial attachment by 99%. This low-cost, facile, fluorine-free, and scalable method is suitable for a great variety of heat transfer applications.

Abstract: The aim of this study is to enable the hydrogen economy and decarbonize various sectors in our environment that requires less expensive and more durable water electrolyzers, which can meet the Hydrogen-Shot target. The key is to improve the ionomer interfaces in low-temperature water electrolyzers as rapidly as possible, but to do so, it requires a systematic and holistic campaign combining both experiments and theory. In this perspective, we discuss the issues of electrolyzers and needs for translational science. We then present the approach that the Energy EarthShot Research Center: Center for Ionomer-based Water Electrolysis is taking in hopes of inspiring the community with this approach that can be leveraged to multiple problems and technologies. Graphical abstract: (Figure presented.) Highlights: One way to achieve the Hydrogen-Shot goal of low-cost, clean hydrogen, is advancing research and development on the interfaces of water electrolyzers for both performance and lifetime. The Center for Ionomer-based Water Electrolysis is exploring new techniques and strategies to not only interrogate interfacial phenomena in water electrolyzers to increase efficiency and durability, but also a new paradigm related to synergistic, cojoined experimental and theoretical research. Discussion: Catalyst\ionomer interfaces are complex and not fully understood, but through investigating different interfaces and utilizing digital and physical twins, we can elucidate key mechanisms and understanding. Understanding the dynamic double layer in electrochemical systems that use solid electrolytes is crucial to identifying and mitigating the controlling phenomena to enable increased performance and durability at the technology level. Studying the time and length scales of interfacial changes can be a powerful tool to understand reaction mechanisms and changes in the electrolyzer performance and durability.

Proton exchange membrane fuel cells (PEMFCs) are expected to play a pivotal role in decarbonizing the transportation sector, and particularly heavy-duty vehicles (HDVs). However, improvements in durability are needed for PEMFCs to compete with state-of-the-art power sources for HDVs. Here, we examine how catalyst layer (CL) cracks that are engineered affect the CL durability by using patterned silicon templates to control the CL crack density at the micrometer scale. Electrochemical analyses show that the initial PEMFC performance is relatively unaffected by crack density, but the performance after durability testing was strongly affected. Specifically, CLs with high crack density showed higher performance relative to CLs without cracks after application of a carbon corrosion accelerated stress test. Electrochemical analyses coupled with X-ray computed tomography and scanning transmission electron microscopy with energy dispersive X-ray spectroscopy showed that the cracks provide shorter oxygen diffusion pathways to reaction sites, leading to decreased oxygen transport resistance. Additionally, we observed that the catalyst durability is unaffected by cracks. Our results provide a mechanistic explanation of the role of cracks in CL durability.

Thermal barrier coatings (TBCs) reduce the surface temperature of superalloy components but may affect the mechanical properties of the substrate. This study investigates the creep-fatigue behavior of TBC-coated single-crystal superalloys under 1 s, 60 s, and 180 s dwell times. The results indicate that TBCs are beneficial at a 1 s dwell time. The comparison of fracture morphology between coated and uncoated samples showed no change in the failure mechanism due to TBCs under creep-fatigue loading. A creep-fatigue lifetime prediction method based on continuous damage mechanics was also proposed. The predicted results were all within a double dispersion coefficient, showing good agreement with the experimental results. This study provides insights into the durability of TBC-coated single-crystal superalloys under creep-fatigue loading. [ABSTRACT FROM AUTHOR]

Thermal runaway poses a critical safety concern for fuel cells, significantly impairing their performance and durability. Uneven current often leads to uneven temperature, exacerbating the risk of thermal runaway. The inadequate electrical and thermal conductivity of the gas diffusion layer (GDL) is identified as the primary cause of the safety issues. To address this, a multilayer composite gas diffusion layer (MC‐GDL) is proposed and designed to enhance both electrical and thermal conductivity. The in‐plane electrical conductivity of the MC‐GDL reaches an impressive 9.1 × 104 S m−1. Under extreme uneven current, the fuel cell's performance with MC‐GDL only declines by 3.7%, compared to a substantial 58.1% decline observed with commercial GDL. Additionally, the in‐plane thermal conductivity of the MC‐GDL is notably high at 337.0 W m−1 K−1. Under extreme uneven temperature, the maximum temperature of Nafion membrane in fuel cell equipped with MC‐GDL is only 84.2 °C significantly lower than the 180.7 °C observed with commercial GDL. Consequently, the MC‐GDL effectively prevents the melting, thinning, and perforation of the Nafion membrane, thereby mitigating thermal runaway. Furthermore, the superior electrical and thermal conductivity of MC‐GDL can enhance the safety of other electrochemical devices by minimizing uneven current and thermal runaway. [ABSTRACT FROM AUTHOR]

In this study, nano-sized Al 2 O 3 and Gd 0.1 Ce 0.9 O 1.95 (GDC) particles are added to La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) cathode material as sintering inhibitors for solid oxide fuel cells (SOFC) to improve the stability of the cell performance. Studies reveal that as the amount of the inhibitors increases, the sintering activation energy of the composite LSCF sample increases, resulting in retarded sintering kinetics indicated by the suppressed grain size of the sintered composite LSCF cathode. Long-term durability tests show that due to the enhanced stability of the microstructure of the composite LSCF cathode, the composite cathode exhibits improved performance stability. Furthermore, both the Al 2 O 3 and GDC additions can improve the hardness and elastic modulus of the cathode, while the electrical conductivity of both cathodes exceed 100 S/cm and can still meet the requirements for the SOFC in the operation temperature range of 600–800 °C. In light of the boosted electrochemical durability of the Al 2 O 3 -added LSCF cathode and much lower cost of Al 2 O 3 compared to the rare-earth element based GDC materials, LSCF cathode with a proper amount of the nano-sized Al 2 O 3 inhibitors is a good solution to enhance the mechanical property, electrochemical durability of LSCF cathode for the SOFCs at low cost. [ABSTRACT FROM AUTHOR]

Conventional phosphoric acid (PA) doped polybenzimidazole are regarded as the most promising materials for high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs). Yet, their practical application has been hindered by their high production cost, poor oxidation stability, and loss of PA at low temperatures. Here, a polymer of intrinsic microporosity containing “sulfide‐linkage” radical‐sacrificial‐agent is designed with good solubility and high PA retention, which enables it to operate for long periods at 80–180 °C. Specifically, the “sulfide‐linkage” radical‐sacrificial‐agent enabled PSBI‐IM to be durable for 100 h with mass retention still higher than 90%, and the capillary effect of the micropores enabled PSBI‐IM/PA to retain more than 60% of PA under high humidity. After rational optimization, the cell assembled with PSBI‐IM/PA achieved a power density of 1.62 W cm−2 with a specific power of 2.7 W mg−1 and an operating time of more than 500 h (0.2/0.4 A cm−2@160 °C). In addition, the voltage drop is only 5% even after 40 h of accelerated stress testing at 0.4 A cm−2@ 80 °C. Therefore, the PSBI‐IM/PA can be stabilized over a wide temperature range from 80 to 160 °C, providing a new material for the HT‐PEMFCs with flexible operational temperature. [ABSTRACT FROM AUTHOR]

Is there a positive sexuality gap in access to political candidacy and elected office, similar to those found in other forms of political engagement? We utilise validated data on same- and different-sex families from the Swedish administrative registry to descriptively examine long-term trends in access to political candidacy and elected office among Swedish lesbian, gay, and bisexual (LGB) persons. With data covering twenty-four elections and a sample size of nearly seventy million individuals, our findings reveal a gradually emerging positive sexuality gap in access to political candidacy and a declining share of ‘sacrificial lambs’ among LGB candidates. We verify the robustness of these findings with the help of two original representative samples from the Swedish population. By shedding light on the existence and durability of a positive lavender gap in access to political candidacy, this study contributes to existing debates concerning the obstacles to minority political participation and descriptive representation and how they might be overcome. [ABSTRACT FROM AUTHOR]

With growing environmental concerns due to the excessive use of natural river sand in construction, finding sustainable alternatives is crucial. This study explores the potential of basalt waste dust, a by‐product of basalt rock crushing, as a replacement for river sand in one‐part geopolymer mortar. The experimental program is segmented into three series: replacing river sand with basalt waste dust at 25%, 50%, 75%, and 100%; adjusting the activator‐to‐binder ratio as 0.12, 0.15, 0.18, and 0.21; and modifying the aggregate‐to‐binder ratios (1, 1.4, 1.8, and 2.2). Results are discussed using various test results such as fresh property, hardened property, and microstructural property to provide a detailed analysis of mixture properties. Findings in series 1 reveal that replacing 50% of river sand with basalt waste dust optimally enhances the fresh and hardened properties of geopolymer mortar. In series 2, the varying activator‐to‐binder ratio with optimum replacement from series 1, activator‐to‐binder ratio 0.15, was found to be optimal, improving hardened properties. Further opting for this ratio in series 3 and increasing the aggregate‐to‐binder ratio to 2.2 was found to positively impact both the hardened and microstructural properties of one‐part geopolymer mortar. This study demonstrated that basalt waste dust plays a crucial role in these improvements and emphasizes the necessity of optimizing mix proportions to achieve superior performance, establishing basalt waste dust as a viable and sustainable alternative to river sand. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Materials and Methods Results Conclusion Trial Registration Several treatment modalities have been used to restore crown fractures in case of uncomplicated crown fractures. Although many treatment modalities have been reported, there is no consensus on which one has the best results in terms of success and durability. This systematic review of treatment modalities in uncomplicated crown fractures aims to provide the most common and successful treatment modality for each patient's unique needs, balancing conservation, aesthetics, and long‐term durability.Three electronic databases (PubMed, Scopus, and Google Scholar) were searched for articles regarding treatment modalities in uncomplicated crown fractures in anterior maxillary teeth.Following the application of the inclusion and exclusion criteria, 10 case reports, four case series, and two retrospective studies were selected for the review. These studies reported on fragment reattachment, direct composite resin, and veneers for the management of uncomplicated crown fractures. Fragment reattachment was the most preferred treatment modality, with milk, water, or sterile saline used as storage mediums. Direct composite restoration was preferred for missing or bad‐shaped fragments or longevity. Veneers were given for aesthetic consideration and fracture resistance when the crown structure was majorly affected by the fracture. Fragment reattachment was favored in 63% of the articles included in the review followed by direct composite restoration in 26% of the articles. Venners were used in about 11% of the articles. Composites depicted a higher survival rate and a better outcome than fragment reattachment. Follow‐up periods ranged from 1 week to 4 years, and all articles successfully re‐established function and aesthetics, except for one tooth that required root canal treatment.Fragment reattachment, direct composite restoration, and veneers are successful treatment modalities in uncomplicated crown fractures of anterior teeth. The choice of treatment depends on various factors like availability of fragments, age, and financial condition of the patient.PROSPERO Registration ID: CRD42020153091 [ABSTRACT FROM AUTHOR]

Ammonia is increasingly considered a promising zero-carbon hydrogen energy carrier owing to its favorable properties for storage, transport, and distribution. The direct utilization of ammonia in solid oxide fuel cells (SOFCs) has the potential to offer a highly efficient power source with high energy density. However, the poor stability and low catalytic activity of conventional Ni-based anodes for ammonia utilization significantly limit the performance and application of ammonia SOFCs. Here, we report the development of a new anode composed of exsolved nanoparticles from an Sr(Ti, Fe, Ru)O 3−δ (STFR) perovskite structure and a catalytic iron layer (STFR + Fe), which considerably enhances activity and durability for ammonia utilization. The La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3−δ electrolyte-supported cell with an STFR + Fe anode shows peak power densities of 1.25 W/cm2 at 800 °C and 0.76 W/cm2 at 700 °C with NH 3 as fuel. These power densities surpass 85% of those achieved using H 2 as fuel and are significantly higher than those of cells with an Ni–Ce 0.9 Gd 0.1 O 2−δ (Ni-GDC) anode (0.38 W/cm2 at 700 °C). Additionally, the STFR-Fe anode demonstrates exceptional stability when operating at a constant voltage of 0.75 V at 800 °C. The current density of the cell exhibits a marginal decrease from 1.33 A/cm2 to 1.32 A/cm2 after 120 h of testing, corresponding to a degradation rate of 0.006%/h, which is substantially lower than that of the Ni-GDC cell (degradation rate 0.283%/h). This degradation rate is the lowest ever reported, highlighting the superior stability of the STFR + Fe anode system. [Display omitted] • The MPD of STFR + Fe anode cell using NH 3 fuel is over 85% of that using H 2 fuel. • The cell with STFR + Fe anode achieves MPD of 1.25 W/cm2 at 800 °C when using NH 3 fuel. • MPD of STFR + Fe anode cell reaches 1.9 times that of Ni-GDC + Fe anode cell at 700 °C. • STFR + Fe anode in NH 3 fuel has a performance degradation rate of 0.006%/h at 800 °C. [ABSTRACT FROM AUTHOR]

As the most widely used building material, cement has attracted the attention of scholars because of its large carbon emission. To alleviate the problems of carbon emission and limited resource use caused by cement production, this study focuses on the performance of mortar after carbonization curing by regulating the composition of ternary binders. Testing involved mechanical parameters, carbon shrinkage, water absorption, hydration product, microstructure, adsorption of carbon dioxide, calcium carbonate content, and carbonization degree of mortar, as well as comparisons with the effect of calcium carbide slag and sintered red mud. We carried out several studies which demonstrated that carbonization curing and adjusting the content of calcium carbide slag and sintered red mud were beneficial to improve the mechanical properties, peak load displacement, slope, elastic energy, plastic energy, carbon shrinkage, carbon dioxide adsorption, calcium carbonate content, and carbonization degree of mortar, while the addition of calcium carbide slag and sintered red mud increased the water absorption of mortar, and the greater the dosage, the greater the water absorption. Meanwhile, adding 25%–50% calcium carbide slag and sintered red mud still had negative effects on the mechanical properties of mortar. But carbonation curing and the addition of calcium carbide slag and sintered red mud could promote the hydration reaction and consume calcium hydroxide formed by hydration to form calcium carbonate. When the dosage was 50%, the carbon dioxide adsorption capacity, calcium carbonate content, and carbonization degree of calcium carbide slag mortar were higher than those of sintered red mud mortar, which increased by 29.56%, 102.73%, and 28.84%, respectively. By comparison, calcium carbide slag and sintered red mud still showed superior carbon sequestration capacity, which was higher than fly ash and Bayer red mud. From the experiment, we came to realize that adjusting the composition of cementitious materials could realize the carbon sequestration of cement-based materials and promote the road toward low-carbon sustainable development of cement. [ABSTRACT FROM AUTHOR]

The usage of manufactured sand concrete is widespread in modern engineering, and it is important to study its performance to improve the overall engineering quality. This paper presents an experimental study on the working performance and durability of 12 groups of manufactured sand high-performance concrete (MSHPC) with varying mix ratios, in the context of the construction of the Dalian Bay undersea immersed tube tunnel. The study reveals that the stone powder content significantly affects the physical and mechanical properties, as well as the durability, of manufactured sand concrete. At an approximately 9% stone powder content, the concrete achieves the highest slump and best workability. However, excessive stone powder reduces early crack resistance. Furthermore, an optimal stone powder content (ranging from 5% to 13%) enhances the compressive strength, with the 28-day compressive strength reaching 60 MPa at a 13% stone powder content, while the effect on the splitting tensile strength is negligible. The stone powder content does not significantly impact impermeability and frost resistance, but at 7–9%, the RCM method shows the lowest chloride ion diffusion coefficient. Additionally, a lower water–binder ratio enhances resistance to chloride ion diffusion. High-performance RCM concrete with a 9% stone powder content was used in the construction of the Dalian Bay Cross-Harbor Tunnel, achieving 28-day and 56-day compressive strengths of C45 and C50, respectively, an impermeability grade of P14, a chloride ion diffusion coefficient of 1.9 × 10−12 m2/s, and a frost durability index of 92%, meeting the project's 100-year lifespan design requirements. [ABSTRACT FROM AUTHOR]

In this study, a wear-resistant ultra-thin wear layer was fabricated with polyurethane as an adhesive to investigate its durability for pavement applications. Its road performance was investigated based on indoor tests. First, the abrasion test was performed using a tire–pavement dynamic friction analyzer (TDFA), and the surface elevation information of the wear layer was obtained by laser profile scanning. The relationship between the anti-skid properties of the wear layer and the macro-texture was analyzed. Second, a Fourier infrared spectrometer and scanning electron microscope were employed to analyze the evolution of polyurethane aging properties in the pull-out test and accelerated ultraviolet (UV) aging test. The results showed that the mean profile depth (MPD), arithmetic mean wavelength of contour (λa), surface wear index (SBI), stage mass loss rate (σ), and total stage mass loss rate (ω) of the abrasive layer aggregate had significant multivariate quadratic polynomial relationships with the skidding performance of the abrasive layer. The tensile strength of the polyurethane ultra-thin abrasive layer decreased by only 2.59% after 16 days of UV aging, indicating a minimal effect of UV action on the aggregate and structural spalling of the polyurethane abrasive layer. [ABSTRACT FROM AUTHOR]

A method for creating broadband ultrathin azo dye micropolarizers is introduced, utilizing photoalignment technology and liquid crystal polymers to organize azo dyes into a long-range ordered structure. Achievements include a 3.63 μm thick polarizer with an extinction ratio over 140 and polarization efficiency over 99.3% across 400–650 nm, 5 μm × 5 μm pixel pitch flexible ultrathin checkerboard arrays and 6 μm pixel pitch flexible ultrathin one-dimensional grating with a 0.45 duty ratio through mask exposure technology. After a substrate-transfer technique, the bending cycle test demonstrates the mechanical stability and durability of the broadband ultrathin flexible polarizers, highlighting their potential for widespread use in integrated flexible optoelectronic systems. [ABSTRACT FROM AUTHOR]

Engineered cementitious composites (ECCs) have garnered significant attention within the construction industry, owing to their exceptional mechanical properties and durability. This thorough review presents a meticulous analysis of the progress and prospects in ECC research. It begins by introducing the background and rationale for investigating ECCs, while outlining the objectives of the review. The review provides an encompassing overview of ECCs, encompassing their definition, characteristics, historical development, composition and constituent materials. Emphasis is placed on the examination of ECCs' mechanical properties, specifically their flexural behaviour, tensile behaviour, compressive strength and resistance to environmental factors. Furthermore, the rheological properties of ECCs, including workability, flowability, self-healing, crack mitigation, viscosity and thixotropy, are discussed in detail. The review delves into the influence of fibre reinforcement on ECCs, encompassing the types of fibres utilised and their impact on mechanical and structural properties, as well as fibre dispersion and orientation. Additionally, it explores the diverse applications of ECCs across various fields, such as structural applications and sustainable building practices. The challenges and limitations associated with ECCs, such as cost and availability, are addressed, alongside an exploration of future trends and research directions. [ABSTRACT FROM AUTHOR]

ABSTRACT The desire to use additively manufactured (AM) parts to ensure the availability of military aircraft, and to build limited‐life unmanned aerial vehicles (drones), coupled with the United States Air Force (USAF) approach to the airworthiness certification of AM parts has focused attention on durability analysis/assessment, and hence on the growth of small cracks in AM parts. Previous studies have shown that laser powder fusion built (LPBF) Scalmalloy® has: i) A yield stress and an ultimate strength that are greater than that of AA2024‐T3 and comparable to that of AA7075‐T6; ii) A resistance to crack growth that is better than that of AA7075‐T6 and comparable to that of AA2024‐T3. However, since the ability to predict the durability of a part is essential for its airworthiness certification, the present paper illustrates how to perform a linear elastic fracture mechanics (LEFM)‐based durability assessment of Boeing Space, Intelligence and Weapon System (BSIWS) LPBF Scalmalloy®. The durability study includes specimens with both machined surfaces and surfaces left in the as‐built condition. As a result, it would appear that BISWS AM LPBF Scalmalloy® is an ideal candidate for building limited‐life AM replacement parts for fixed and rotary wing aircraft and drones. [ABSTRACT FROM AUTHOR]

This paper aimed to investigate the durability of ambient-cured fly ash-phosphogypsum blended geopolymer mortar (GPM) when exposed to a water and sulfate environment at different durations. Water absorption, porosity, and sulfate resistance tests were conducted to determine the durability. The GPM was prepared at 0 wt%, 30 wt%, and 40 wt% PG replacement of fly ash content in the mixture. The mix proportions were determined experimentally at 10 M sodium hydroxide, alkaline liquid/precursor of 0.4, sodium silicate/sodium hydroxide of 1.5, and binder/aggregate of 1.0. The samples were immersed in potable water and magnesium sulfate solution. The changes in weight, length, and compressive strength were monitored. Scanning electron microscopy-energy dispersive X-ray spectroscopy was used to analyze the structure and composition. The findings showed that GPM with 30 wt% phosphogypsum added had lower water absorption, porosity, and sulfate attack than GPM with 0 wt% phosphogypsum attributed to the formation of hydrated gels leading to a dense microstructure and improved strength. The changes in weight, length, and strength variations trend for GPM were within optimal performance standards. This has implications for the practical application of GPM in construction where it can be used as an alternative to Portland cement mortar in sulfate-rich environments. [ABSTRACT FROM AUTHOR]

Recent advancements in concrete technology focus more on increasing strength than durability. Concrete with good durability will withstand adverse conditions like frost, chloride penetration, sulfate assault, alkali-aggregate reaction, steel corrosion, etc., which will lower the strength of the concrete. Strength is vital, but so is durability. The present study examined and discussed the durability parameters of conventional concrete made with geopolymer aggregate (GPA) as a partial substitute for natural aggregate. Strength studies in this research found that the optimal level of substitution for natural coarse aggregate by GPA was 100% replacement to produce the performing concrete. Replacement of natural coarse aggregate by geopolymer aggregate exhibits 9%-15% higher compressive strength than natural aggregate concrete. The findings reveal that concrete with 100% geopolymer aggregate exhibits a compressive strength increase of 9%-15% over that of concrete made with natural aggregates. Ultrasonic pulse velocity measurements for geopolymer aggregate concrete range between 4 km/s and 4.5 km/s, indicating good quality according to IS specifications. Additionally, Rebound Hammer test results further support the enhanced quality of geopolymer aggregate concrete. However, the porosity of geopolymer aggregates results in a sorptivity that is 10%-30% higher than that of natural aggregate concrete. Despite this, the increased resistance to acid and sulfate attacks is noted, attributed to the strong bonding between geopolymer aggregates and the cement matrix. [ABSTRACT FROM AUTHOR]

Cold start impedes widespread diffusion of fuel cell vehicles (FCVs) in regions with temperatures below zero. Alternating hydrogen pump (AHP) method, distinguished by its unlimited ohmic heating capability without generating water, has been shown to be a quick and efficient method of cold starts in both single cell and short stacks. In this paper, we continue to examine possible degradation with this novel method. For this purpose, we carefully designed three experiments with different levels of stress, aimed to separate the contribution to any degradation from major factors. It was found there was no significant difference among the three cases. AHP method incurred minimal degradation after 3600 times of equivalent −30 °C cold starts. This study concludes that AHP method is not only quick and efficient, but also highly durable, hence AHP is a promising alternative cold start strategy with great potential to facilitate the diffusion of FCVs. • Durability of PEMFC cold start adopting AHP method is investigated. • A cell with variable clamping pressure is exploited. • An accelerated stress test protocol using AHP method is adopted. • Three comparable experiments are designed to decouple degradation. • AHP method is intrinsically an ultralow-degradation cold start strategy. [ABSTRACT FROM AUTHOR]

The expansive development of infrastructure has led to increased consumption of virgin aggregates in road construction, resulting in significant environmental impacts. To address this issue, there is a pressing need for sustainable alternatives that utilize recycled materials in pavement applications. This paper presents a comprehensive review of a decade-long research program focused on the development and evaluation of sustainable pavement materials, such as recycled and waste aggregates, industrial by-products, and natural fibers. The research encompassed a wide range of innovative materials and technologies, such as geopolymer-stabilized recycled aggregates, cement-stabilized waste materials, natural additive-modified cement stabilization, and recycled aggregate-geogrid reinforcement systems. The experimental framework employed a combination of mechanical testing, durability assessment, microstructural analysis, and environmental safety evaluation to assess the performance and sustainability of these materials. The key findings demonstrated the superior mechanical properties, improved durability, and environmental suitability of the recycled materials compared to conventional virgin aggregates. The successful implementation of these sustainable solutions in real-world projects highlights their potential to reduce the environmental footprint of road infrastructure development. Furthermore, the paper discussed the practical implications of the research outcomes for pavement design and construction, as well as future research directions to further advance the field of sustainable pavement engineering. The findings of this research report can be used as guidance for researchers, practitioners, and policymakers seeking to upcycle the widespread adoption of recycled materials in road application and contribute to the development of a more sustainable and resilient transportation infrastructure. [ABSTRACT FROM AUTHOR]

The European Green Deal (EGD) has had a significant impact on EU member states. In this article, we examine the extent to which it can also have large consequences for non-members. Based on a qualitative approach comparing Norway and the UK, and drawing on a burgeoning literature on 'turbulence', we ask whether the EGD creates turbulence in non-member states, what the nature of this turbulence is, and whether the extent and nature of turbulence varies with how closely affiliated a non-member is with the EU. Despite the ambitious climate policies of both countries, we identify a significant amount of turbulence generated by the EGD. Interestingly, we also find that turbulence increases with a closer EU-affiliation. However, our analysis also reveals an impressive capacity in both countries to adapt to their turbulent conditions, and a surprising durability of climate and energy policy in the face of turbulence. [ABSTRACT FROM AUTHOR]

Background: Studies evaluating the attrition, physical and insecticidal durability of dual active ingredient (AI) insecticide-treated nets (ITNs) are essential for making programmatic decisions regarding their deployment. We performed a prospective study embedded in a cluster randomised controlled trial (cRCT) to evaluate the attrition, fabric integrity and insecticidal durability of Interceptor® G2 (alpha-cypermethrin-chlorfenapyr) and Royal Guard® (alpha-cypermethrin–pyriproxyfen), compared to Interceptor® (alpha-cypermethrin) in Benin. Methods: A total of 2428 study nets in 1093 randomly selected households in five clusters per arm of the cRCT were monitored for ITN attrition and fabric integrity every 6–12 months post-distribution. Householders were further surveyed to investigate non-study net use and their preference for ITN fabric types used in the study nets. A second cohort of 120 nets per ITN type were withdrawn every 12 months and assessed for chemical content and insecticidal activity in laboratory bioassays. Alpha-cypermethrin bioefficacy was investigated using the susceptible Anopheles gambiae Kisumu strain, and chlorfenapyr and pyriproxyfen bioefficacy were investigated using the pyrethroid-resistant Anopheles coluzzii Akron strain. Net pieces were tested in WHO cone bioassays and tunnel tests for alpha-cypermethrin and in tunnel tests for chlorfenapyr; pyriproxyfen activity was assessed in cone bioassays as the reduction in fertility of blood-fed survivors using ovary dissection. Bioefficacy was expressed as the proportion of ITNs passing predetermined WHO criteria, namely knock-down ≥ 95% or 24/72 h mortality ≥ 80% or reduction in fertility ≥ 50%. Results: Overall ITN survivorship was 52% at 24 months and fell to 15% at 36 months. Median ITN survival time was lower with Royal Guard® relative to Interceptor® [1.6 vs 2.3 years; hazard ratio (HR) 1.49, 95% confidence interval (CI) 1.36–1.66; p < 0.001] and Interceptor® G2 (1.6 vs 2.1 years; HR 1.33, 95% CI 1.20–1.47; p < 0.001). Householders overwhelmingly preferred polyester nets over polyethylene nets (96%), and more Royal Guard® nets were replaced with spare polyester nets from previous campaigns. All Royal Guard® nets passed efficacy criteria for alpha-cypermethrin at all time points (100%) while ITN pass rates after 24 months had fallen to < 40% for pyriproxyfen and chlorfenapyr. The chemical content analysis showed a higher loss rate of the non-pyrethroid insecticides relative to the pyrethroids in each dual ingredient AI ITN; 74% vs 47% for Royal Guard® and 85% vs 63% for Interceptor® G2 at 36 months. Conclusions: The median ITN survival time for Interceptor® G2 (2.1 years) and Royal Guard® (1.6 years) in Benin is substantially lower than 3 years. Royal Guard® nets were discarded more quickly by householders, partly due to their low preference for polyethylene nets. The insecticidal activity of the non-pyrethroid insecticides in both dual AI ITNs was short-lived compared to alpha-cypermethrin. The results corroborate the findings from the cRCT conducted in Benin. [ABSTRACT FROM AUTHOR]

Abstract\nIMPLICATIONS FOR REHABILITATIONIn this study, 3D printing-based solutions are sought to improve the durability of guide canes of visually impaired individuals. The financial inaccessibility of technological white canes is a challenge that this study addresses by integrating additive manufacturing. The proposed solutions are designing a ball caster tip with a suspension mechanism, manufacturing a barrier detection and vibration alert system, and a 3D-printed flexible cover for the guide cane. Each solution is specially prototyped for this study using Computer-Aid Design (CAD). It aims to produce accessories that can upgrade any regular cane to a more durable and comfortable state by easily clipping them onto any cane. The solutions were assessed under three criteria, for which the visually impaired consultee of the research was assigned weights for further evaluation. The assessment has been conducted based on each solution’s effectiveness, cost, and comfort. According to the evaluation of the visually impaired consultee, the ball caster with suspension mechanism yielded the highest score for the assessment criteria. Further recommendations have been made for each solution to decrease the volume occupancy and increase lifespan, durability, and comfort.Modular Computer-Aid Designing (CAD) of white cane accessoriesNovel ball caster module with a suspension mechanismSensitive barrier detection with ultrasonic sensors and alerting with vibration3D printing flexible thermoplastic polyurethane (TPU) cover for cane segment [ABSTRACT FROM AUTHOR]

We evaluated the effects of behavioral skills training on improving participant implementation of functional communication training with multiple schedules when working with a confederate. Behavioral skills training produced mastery‐level responding for all six participants who required training, providing the first empirically supported training for this functional communication training approach. Next, we assessed durability during training challenges with (a) procedural changes to the original protocol, (b) a novel confederate with different discriminative stimuli and reinforcers, and (c) relapsed confederate destructive behavior. Training effects degraded at least once for all participants and in 62% of training challenges, although continuing to expose the participant to the challenging situations or providing postsession booster training resolved the degradation in most cases. We discuss these findings in relation to their clinical implications and directions for future research. [ABSTRACT FROM AUTHOR]

The influence of a Griffith fracture on magnetic fields and stress in an infinite piezomagnetic material under tension loading and magnetic has been explored using linear theory of piezomagnetic material and suitable boundary conditions. The solutions have been obtained in closed form for Mode I fracture and external loading utilised to open the fracture. The rate of energy release has been determined for the non-zero magnetic field within the fracture at the crack tip. During computation of driving force, the magnetostatic energy has been taken into account and it has been observed that the rate of energy release is the cubic function of external loading. The findings could be utilised to explain various nonlinear phenomena in piezomagnetic ceramic for structural durability. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of the CaO and fly ash (FA) dosage and proportion on the mechanical properties, durability, and microstructure of solidified sludge, freeze–thaw (F-T) cycles and dry–wet (D-W) cycles are conducted to study the change in appearance and the strength attenuation of CaO-FA solidified sludge. Low-field nuclear magnetic resonance (LF-NMR) is used to analyze the microstructure of the solidified sludge with various dosages and ratios of CaO-FA. The results demonstrate that the unconfined compressive strength (UCS) and direct shear strength of solidified sludge increase with the prolongation of the curing age. Furthermore, the mechanical properties of solidified sludge are improved as the ratio of CaO-FA increases. As the curing age increases, the distribution of transverse relaxation time (T2) becomes narrow, the spectral area decreases, and the amplitude of the LF-NMR signal shows a downward and leftward tendency. Additionally, with the increase in the number of F-T cycles and D-W cycles, the UCS of solidified sludge declines and the degree of pore deterioration increased gradually. This study offers a theoretical foundation and empirical data for the dredging and treatment of sludge in cold regions. [ABSTRACT FROM AUTHOR]

When building a tunnel in an environment rich in high‐temperature hot water, it is particularly necessary to pay attention to the influence of sulfate ions in underground hot water on tunnel shotcrete. In order to study the sulfate erosion mechanism and mechanical properties of shotcrete in a real high‐temperature hot water environment, this study was carried out by setting the curing temperature (20, 40, 60, and 80°C), humidity (55% RH, 95% RH), and erosion age (0, 15, 30, 60, and 90 d) as the test influencing factors; a full combination of dry‐wet cycle test was carried out, and the specimens under different conditions were analyzed macroscopically and microscopically. The results show that with the increase of the number of dry‐wet cycles, the quality of shotcrete increases first and then decreases, and the mechanical properties gradually decrease. In the early stage of erosion, the erosion product is mainly ettringite, and the macroscopic damage is aggregate spalling. In the later stage of erosion, the erosion product is mainly gypsum, and the macroscopic damage is expansion damage. Compared with standard curing, a certain degree of high temperature curing has little effect on the sulfate attack resistance of shotcrete, but when the curing temperature exceeds 60°C, the concrete is seriously damaged. Finally, by constructing the damage model of sulfate attack shotcrete, the variation of compressive strength of shotcrete with age after sulfate attack under different curing conditions was successfully predicted. [ABSTRACT FROM AUTHOR]

\nHIGHLIGHTSThis study focuses on enhancing cementitious materials by incorporating silanized graphene oxide (SGO) and superabsorbent polymers (SAPs), aiming to improve their mechanical and durability properties. The primary goal is to evaluate the effects of SGO/SAP composites on the hydration, absorption, shrinkage, and overall performance of concrete. The composites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) to understand their microstructure. Mechanical and durability tests revealed that adding SGO/SAP composites significantly increased the mechanical strength and water absorption capabilities of the concrete. The compressive strength, split tensile strength, and flexural strength of the SGO/SAP-modified concrete were measured at 57 MPa, 4.90 MPa, and 8.25 MPa, respectively. Shrinkage tests demonstrated the composite hydrogel’s excellent water-holding capacity at 0.3 wt.% SGO/SAP, facilitating internal curing in concrete structures. FE-SEM analysis indicated a reduction in microcracks due to the presence of SGO/SAP. The improvements are attributed to the synergistic effects of SGO and SAP, which enhance water retention, dispersion, and interfacial bonding within the cementitious matrix. The microstructural studies confirmed the exceptional stability of the SGO/SAP-modified mix, emphasizing its potential as an additive to improve concrete properties. This research underscores the significant potential of SGO and SAP in advancing the performance of cement-based materials, highlighting their applicability in infrastructure development and construction for creating more durable and high-performing concrete structures. The SGO/SAP significantly enhances the durability of cement-based materials.The SGO/SAPs exhibit superior water absorption and retention properties.Enhanced mechanical strength of SGO/SAP hydrogel-modified concrete.The durability characteristics of cement mortar improved by SGO/SAP hydrogelA decrease in the agglomeration of nanocomposite particlesThe SGO/SAP significantly enhances the durability of cement-based materials.The SGO/SAPs exhibit superior water absorption and retention properties.Enhanced mechanical strength of SGO/SAP hydrogel-modified concrete.The durability characteristics of cement mortar improved by SGO/SAP hydrogelA decrease in the agglomeration of nanocomposite particles [ABSTRACT FROM AUTHOR]

Perovskite solar cells are actively investigated for their potential as highly efficient and cost‐effective photovoltaic devices. However, a significant challenge in their practical application is enhancing their durability. Particularly, these cells are expected to be subjected to heating by sunlight in real‐world operating environments. Therefore, high‐temperature durability and device operation under such conditions are critical. Our study aims to improve the durability of perovskite solar cells for practical applications by examining their temperature coefficients at elevated temperatures using MA‐free compositions. We assessed these coefficients and investigated their correlation with the ideality factor, revealing that carrier recombination markedly affects the temperature behavior of these cells. Our methodology involves simple J‐V measurements to evaluate device degradation at high temperatures, paving the way for further research to enhance device performance in such environments. [ABSTRACT FROM AUTHOR]

Two‐dimensional nanofluidic membranes are promising candidates for various applications, such as energy conversion and ionic sensing. However, simultaneously achieving high stability and high ion transport in a nanofluidic membrane remains a great challenge. Herein, a robust and durable aramid nanofiber/carboxylated aramid nanofiber (ANF/cANF) nanofluidic hybrid membrane is designed with high ion conductivity and selectivity via surface grafting engineering and hybridization strategies. Due to the inherent ordered and asymmetric molecular structure, the strong interchain interactions of the ANF and the strong interfacial interactions between the ANF and cANF enable the membrane to exhibit robust structural stability in a wet state. Meanwhile, the enhanced surface charge enabled by the surface functionalization of carboxyl groups on the ANF results in excellent ion transport. As a result, the conductivity of the membrane is 5 and 36 times higher than the ANF membrane and bulk solution, respectively. Importantly, the ionic conductivity and mechanical strength of the membrane remain unchanged even after immersing in water for 90 days, demonstrating favorable underwater application potential. Moreover, the membrane is recyclable and has superior processability, allowing for large‐scale processing. This work provides a new strategy for designing durable and high‐ion‐transporting nanofluidic membranes for ion sensing and energy conversion. [ABSTRACT FROM AUTHOR]

The slake durability and the related deterioration mechanism of carbonaceous rocks exposed to adverse external environment are of a great importance to the stability of infrastructure. A series of laboratory tests were conducted to determine their slake durability index Idi, fractal dimension D, total organic carbon (TOC) content, and mineralogical characteristic. The results demonstrated that Idi value decreased rapidly within the first 4 cycles, and then reached a relatively stable state as the test cycle further increased, indicating that effective protective measures should be conducted at the earlier stage of wetting-drying process to minimize the durability deterioration of carbonaceous rock. The discrepancy of carbonaceous rocks in terms of mineralogical characteristic accounted for different slake durability responses at a given cycle. Carbonaceous rock with lower clay minerals content wc possessed superior slake durability performance, and a power correlation between Id6 and wc was obtained. Fractal dimension D was found to be an indicator to indirectly describe the durability characteristic of carbonaceous rock. The organic matter imposed negative impact on the slake durability, which was manifested by the carbonaceous rock with higher TOC content exhibited inferior disintegration resistance. The microstructure changes, including an increase in pore volume, pore size, layer spacing, and the presence of new crystalline-like substances, demonstrated the minerals/salts dissolution and chemical reactions within the rock matrix occurred during the slake durability test. These changes were mainly attributed to the hybrid influence of mineralogy and microstructure of carbonaceous rock. [ABSTRACT FROM AUTHOR]

Crack detection plays a crucial role in evaluating the safety and durability of civil infrastructure. However, detecting cracks of uneven intensity in complex backgrounds is challenging. To overcome this problem, we propose a dual decoder network (CSMT) based on a multi-branch aggregation Transformer, which uses residual atrous spatial pyramid pooling (RASPP) and Transformer dual decoding branches to extract local and global features of different structures. To enhance global feature extraction, we designed a multi-branch aggregation Transformer (MAT) that adaptively weights the features of two attention heads from spatial and channel dimensions to achieve intra block feature aggregation between dimensions. Meanwhile, to obtain multi-scale semantic information, we constructed a new decoding branch, RASPP, which embeds a squeeze-and-excitation (SE) module and residual structures into standard ASPP. Finally, we propose a feature adaptive fusion module (FAM) to enhance feature fusion between adjacent layers and codec layers. Many experiments on three benchmark datasets have shown that the proposed CSMT segmentation network provides excellent performance in a variety of complex scenarios. [ABSTRACT FROM AUTHOR]

Gradual disability of Zn anode and high negative/positive electrode (N/P) ratio usually depreciate calendar life and energy density of aqueous Zn batteries (AZBs). Herein, within original Zn2+‐free hydrated electrolytes, a steric hindrance/electric field shielding‐driven "hydrophobic ion barrier" is engineered towards ultradurable (002) plane‐exposed Zn stripping/plating to solve this issue. Guided by theoretical simulations, hydrophobic adiponitrile (ADN) is employed as a steric hindrance agent to ally with inert electric field shielding additive (Mn2+) for plane adsorption priority manipulation, thereby constructing the "hydrophobic ion barrier". This design robustly suppresses the (002) plane/dendrite growth, enabling ultradurable (002) plane‐exposed dendrite‐free Zn stripping/plating. Even being cycled in Zn‖Zn symmetric cell over 2150 h at 0.5 mA cm−2, the efficacy remains well‐kept. Additionally, Zn‖Zn symmetric cells can be also stably cycled over 918 h at 1 mA cm−2, verifying uncompromised Zn stripping/plating kinetics. As‐assembled anode‐less Zn‖VOPO4 ⋅ 2H2O full cells with a low N/P ratio (2 : 1) show a high energy density of 75.2 Wh kg−1full electrode after 842 cycles at 1 A g−1, far surpassing counterparts with thick Zn anode and low cathode loading mass, featuring excellent practicality. This study opens a new avenue by robust "hydrophobic ion barrier" design to develop long‐life anode‐less Zn batteries. [ABSTRACT FROM AUTHOR]

The past two decades have experienced a paradigm shift from a narrow conception of usability to a broader process of user experience. We argue that durable connections to usability remain in TPC. In this perspectives piece, we highlight the paradigm shift and share traces of how the usability paradigm remains durable, primarily in the service course. We share savvy practices of instructors embracing the UX paradigm, even in the face of constraints. [ABSTRACT FROM AUTHOR]

Children's multiple interests intersect with their participation in informal learning practices in dynamic ways. Using a theoretical framework illustrating interest as a multifaceted construct that has different forms and a range of scope and durability, this study investigates how children's situational interests and individual interests are developed and reinforced and how they support micro-practices (i.e., any small practices, actions, activities, interactions that occur moment-by-moment) and vice versa. From a larger data set collected from one-time family science learning sessions at a museum, three children (aged 6–10) were strategically sampled to foreground an enhanced understanding of how interest and participation in practice mutually constitute each other. Using video-based interaction analysis, our case study of three children illustrates different patterns where micro-practices intersect with different types of interests at the museum. Even in the same environment with the same exhibits, each child from this case study constructed a unique pathway of forming the collection of micro-practices that was constantly interacting with situational interests and individual interests in specific disciplines, topics, exhibits, or any other various targets. For example, when having a strongly existing individual interest in a specific science discipline, one child's micro-practices were mainly driven by making choices of exhibits that are related to his science interest, while another child did not actively choose exhibits but found her own creative ways to connect her science interest and other new interests. Our study contributes to a more robust conception of interest that highlights the intertwining of multiple, malleable, and moment-by-moment interests and micro-practices in the museum. [ABSTRACT FROM AUTHOR]

The durability of concrete under combined acidic exposure and flexural loading was studied. Concrete specimens were made and subjected to up to 168 days of exposure to flexural loading (stress levels of 0, 0.35 and 0.50 of the 28 day flexural strength) and an acidic environment. Concrete properties such as neutralisation depth, mass change, compressive strength and flexural strength were measured. The compositions of different samples were determined by means of X-ray diffraction and chemical analysis and the microstructure of samples was examined using scanning electron microscopy. The results showed that, with an increase in stress level from 0 to 0.50, the performance of the concrete deteriorated gradually and the deterioration in the tension zone was greater than that in the compression zone. The concrete performance improved within 28 days but deteriorated dramatically afterwards. The acidic solution reacted with the cement paste, leading to the formation of harmful gypsum and the decomposition and dissolution of cement hydration products. An increase in stress level increased the porosity of the concrete, accelerating the rate of acid erosion, which led to a deterioration of concrete performance. [ABSTRACT FROM AUTHOR]

The identification of damage to concrete bridge surfaces is of great significance to maintaining the durability and reliability of bridges. However, it is difficult to identify small areas of damage, especially in high-resolution images. To conduct damage identification research in a targeted manner, this paper proposes a method of multidamage identification in high-resolution images based on You Only Look Once version 5 (YOLOv5). In this paper, a data set labeled with four types of damage (crack, spallation, hole, and rebar) is used for training, validation, and testing. To ensure that the network adequately learns the damage features, the high-resolution images are cropped into subimages via the autoadaptive window cropping method (AWCM) proposed in this paper. The cropping method can crop images according to the label information and protect the damage features from destruction during the cropping process. To avoid overfitting, it is necessary to balance the volume of different types of damage. After balancing, the count for each category is as follows: crack (4,980), spallation (5,225), hole (5,211) and rebar (5,020). The balanced data set can be used to train the deep learning network and construct the multidamage identification model. After identification, the subimages, and the prediction boxes of damages in them are restored to their original high-resolution images. The results show that the mean average precision (mAP) of all classes is 94.2%, and the values for cracks, spallation, holes, and rebars are 86.9%, 98.1%, 92.3%, and 99.4%, respectively, which indicates that the proposed method outperforms the other three methods (inputting original images directly, the sliding window cropping method, and the random centroid cropping method). [ABSTRACT FROM AUTHOR]

To estimate the fatigue life of lightweight automotive structures in compliance with top-down design principles, there is a need for an accurate adhesive joint fatigue life prediction method that is compatible with industrial finite element modeling practices. This paper proposes a method to split the analytical J-integral solution based on the fracture mode of joints. The split mode I and II J-integrals correspond to the opening mode and sliding mode of the bonded joint, respectively. By splitting the J-integral and introducing the concept of the mixed mode ratio, an improved approach for estimating adhesive joint fatigue life is presented, considering the influence of loading modes. The proposed fatigue life prediction method is validated through fatigue tests on a sub-component level bonded structure. The results of the validation demonstrate that the split J-integral analytical solution method, considering the mixed mode ratio, provides better predictions compared to its predecessor approach. [ABSTRACT FROM AUTHOR]

In general, municipal solid waste incinerator bottom ash (IBA) is mainly utilized as fillers in nonstructural concrete products due to its low reactivity. In this study, the high-strength alkali-activated materials (AAMs) using high calcium IBA was developed. A ternary contour diagram was introduced to optimize the composition of thermally activated IBA (TMBA), ground granulated blast furnace slag (GGBS), and fly ash (FA) in AAMs. The result showed that a high concentration of calcium ions in the ternary system contributed to the provision of nucleation sites for the precipitation of products, thus leading to the promotion of hardening. The optimal compressive strength (80–85 MPa) of AAMs was achieved using 60%–80% GGBS content, 10%–40% TMBA content, and 0%–10% FA content. The AAMs showed high resistance to sulphate attack, chloride penetration, and freeze-thaw when the TMBA content was less than 40%. This was attributed to a dense pore structure formation promoted by the presence of calcium minerals (anorthite, wollastonite, mayenite and gehlenite) as indicated in the X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) analysis. The embodied CO2 index of the AAMs was about 59%–87% lower than cement, and it was a cleaner cementitious material. [ABSTRACT FROM AUTHOR]

Reconfiguring practices within the construction industry through the utilization of diverse industrial byproducts is a crucial endeavor. This study was devoted to promoting sustainable construction methodologies while mitigating environmental implications. The focus of the research was the incorporation of reclaimed asphalt pavement (RAP) aggregates into GPC for application as pavement quality concrete (PQC). Leveraging fly ash (FA) and ground granulated blast furnace slag (GGBS) as viable aluminosilicate sources emerged as a judicious strategy for formulating blends that exhibit exceptional attributes at ambient temperatures, thereby circumventing the challenges posed by impractical on-site oven curing. Natural coarse aggregates were replaced with RAP at varying percentages ranging over 25% to 100% and the performance of the binders was assessed across a range of NaOH molarities (10M to 16M). The 14-M, 50% RAP mix exhibited superior strength and durability, achieving permissible compressive and flexural strength after just 7 days of ambient curing (41.80 and 4.72 MPa, respectively), in contrast to the 28 day of curing required for conventional cement concrete. This designed mix also showcased significant resistance to surface abrasion and carbonation, along with exemplary thermal stability as determined by thermogravimetric analysis (TGA). Upon exposure to a 2% H2SO4 concentration (to gauge performance in aggressive environments), higher RAP replacement levels revealed to influence mass and strength loss, but the effect of molarity remained quite moderate. Furthermore, toxicity characteristic leaching potential (TCLP) tests confirmed the immobilization of heavy metals in GPC blends with integrated RAP, thereby endorsing their environmental suitability for the construction of rigid pavements. [ABSTRACT FROM AUTHOR]

Iliofemoral venous obstructive disease can result in significant, potentially debilitating symptoms that can negatively affect quality of life. Unlike arterial disease, patients with deep venous disease have a significantly lower median age, therefore the need for long term stent patency becomes a matter of decades rather than years. Furthermore, iliofemoral lesions frequently require stent placement across the inguinal ligament. Such stents are subject to dynamic stress from leg movement and associated concerns for device fatigue, resulting in stent fracture. The aim of this study was to describe an in vitro 50 year stent fatigue test method designed to assess durability against dynamic stress induced device fracture. Through literature review, cadaver studies, and computer modelling, the most challenging loading was confirmed to be hip flexion across the inguinal ligament. This occurs when the patient adjusts between a seated and standing position. Sit to stand hip flexion at the inguinal ligament was effectively simulated on the bench in this in vitro experimental study. When tested under challenge parameters, hip flexion was reliably found to cause fractures in non-venous nitinol stents. However, a dedicated self expanding nitinol venous stent, engineered for improved durability, underwent up to 50 years of simulated loading on the bench with 15% (3/20) of stents experiencing fractures at 50 years, compared with fractures in 35% (14/40) of non-venous stents tested to 1.4 years; no statistical testing was performed as durations do not match and the objective was to demonstrate the test method. The presented fatigue test method is a suitable approach for evaluating the durability of stents intended for venous use. Venous stents demonstrated superior fatigue resistance compared with non-venous stents via in vitro hip flexion testing. [ABSTRACT FROM AUTHOR]

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