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Quick-drying fabrics, renowned for their rapid sweat evaporation, have witnessed various applications in strenuous exercise. Profiled fiber textiles exhibit enhanced quick-drying performance, which is attributed to the excellent wicking effect within fibrous bundles, facilitating the rapid transport of sweat. However, the evaporation process is not solely influenced by macroscopic liquid transport but also by microscopic liquid spreading on the fibers where periodic liquid knots induced by spontaneous fluidic instability significantly reduce the evaporation area. Here, a cross-shaped profiled fiber with high off-circularity, featured as multiple concavities along the fibrous longitude-axis, which enables the formation of a homogeneous thin liquid film on a single fiber without any periodic liquid knots, is developed. The high off-circularity cross-sections help overcoming Plateau-Rayleigh instability by tuning the Laplace pressure difference, further facilitated by capillary flow along the concave surface. The homogeneous thin liquid film on a single fiber is responsible for maximizing the evaporation area, resulting in excellent overall evaporation capacity. Consequently, fabrics made from such fibers exhibit rapid evaporation behavior, with evaporation rates ≈50% higher than those of cylindrical fabrics. It is envisioned that profiled fibers may provide inspiration for the manipulating homogeneous liquid films for applications in fluid coatings and functional textiles.

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The growing demand for aluminium worldwide makes aluminium recycling critical to realising a circular economy and increasing the sustainability of our world. One effective way to improve the impact of aluminium recycling is to develop cost-efficient automated sorting technologies for obtaining pre-defined high-quality aluminium scrap products, thus reducing undesirable downcycling and increasing environmental/economic benefits. In this work, an innovative facility, which includes singulation, sensor scanning, and ejection, is optimised for the automated sorting of aluminium scraps. The sorting facility is computationally studied by a virtual experiment model based on the discrete element method. The model considers particle-scale dynamics of complex-shaped scraps and mimics the automated operation of the facility. Based on virtual experiment modelling, the flow of scrap is optimized by computation, with the feasible operation of the sorting facility being proposed. Accordingly, the sorting facility has been built and model predictions are confirmed in actual operation.

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With a focus on sustainability and functionality, this Special Issue looks at various topics, including novel food-packaging solutions, bio-based adhesives, and the integration of nanotechnology to improve performance. It emphasizes the importance of understanding limitations and overcoming them through innovation, highlighting the crucial role of bio-based materials in ensuring food safety and quality, especially in the context of the COVID-19 pandemic. Future research areas emphasize the need for holistic approaches that prioritize circularity and sustainability throughout the packaging lifecycle. By fostering collaboration and innovation, this Special Issue aims to make progress towards a more sustainable and resilient future for food packaging.

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Due to their remarkable features of lightweight, high strength, stiffness, high-temperature resistance, and corrosion resistance, carbon fiber reinforced polymers (CFRPs) are extensively used in sports equipment, vehicles, aircraft, windmill blades, and other sectors. The urging need to develop a resource-saving and environmentally responsible society requires the recycling of CFRPs. Traditional CFRPs, on the other hand, are difficult to recycle due to the permanent covalent crosslinking of polymer matrices. The combination of covalent adaptable networks (CANs) with carbon fibers (CFs) marks a new development path for closed-loop recyclable CFRPs and polymer resins. In this review, we summarize the most recent developments of closed-loop recyclable CFRPs from the unique paradigm of dynamic crosslinking polymers, CANs. These sophisticated materials with diverse functions, oriented towards CFs recycling and resin sustainability, are further categorized into several active domains of dynamic covalent bonds, including ester bonds, imine bonds, disulfide bonds, boronic ester bonds, and acetal linkages, etc. Finally, the possible strategies for the future design of recyclable CFPRs by combining dynamic covalent chemistry innovation with materials interface science are proposed.

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The challenges posed by unsustainable practices in today's economy underscore the urgent need for a transition toward a circular economy (CE) and a holistic supply chain (SC) perspective. Benchmarking plays a pivotal role in managing circular SCs, offering a metric to gauge progress. However, the lack of consensus on the optimal benchmarking approach hampers effective implementation of circular business practices. To address this gap, we conducted a systematic review of the literature, identifying 29 pertinent publications. The analysis revealed 30 unique attributes and sub-attributes for benchmarking circularity, which were clustered into five main attributes. The main attributes are goals, subjects, key performance indicators (KPIs), data sources, and evaluation methods, while the sub-attributes are organised as features of the main attributes and depicted as a feature model. Drawing from selected publications, we illustrated each feature with examples. Our model offers a comprehensive benchmarking reference for circularity and will be a valuable tool for managers in the transition toward circularity. Supply chains seeking to benchmark their transition to circularity can apply the reference model to ensure that their benchmarking strategy is consistent with state-of-the-art knowledge. By providing a generic circularity benchmarking approach that is valid for diverse economic sectors, our findings contribute to theoretical efforts to address the lack of generic frameworks for CE.

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Iron is considered as attractive energy carrier in a carbon-free circular energy economy. The reduction of iron oxide is crucial for its applica-tion as a metal fuel as it determines the efficiency of the cycle. Temperature programmed reduction of α-Fe2O3 was monitored by complementary X-ray absorption spectroscopy (XAS) and diffraction (XRD) to obtain the phase composition with high time resolution. Synchrotron Mössbauer spectroscopy (SMS) was additionally employed due to its high sensitivity to the different iron species. Theoretical calculations of surface and bulk adsorption processes were performed to establish the potential reaction pathways and the corresponding energy barriers. A kinetic particle model was then developed to bridge the experimental data and theoretical calculations, which reproduced the reduction onset and behavior. The reduction process was found to be strongly dependent on the heating rate in terms of the reduction window and the observed intermediate species. We propose that a core-shell mechanism determines the reaction by forming an iron layer which subsequently hinders diffusion of water out of the porous particles leading to some unreduced FeO at high temperature. This study demonstrates the need for complementary methods for describing complex heterogeneous systems and overcoming the chemical sensitivity limitations of any single method.

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Widespread use of lead acid batteries (LABs) is resulting in the generation of million tons of battery waste, globally. LAB waste contains critical and hazardous materials, which have detrimental effects on the environment and human health. In recent times, recycling of the LABs has become efficient but the collection of batteries in developing countries is not efficient, which led to the non-professional treatment and recycling of these batteries in the informal sector. This paper proposes a blockchain-enabled architecture for LAB circularity, which ensures authentic, traceable and transparent system for collection and treatment of batteries. The stakeholders-battery manufacturers, distributors, retailers, users, and validators (governments, domain experts, third party experts, etc.)-are integrated in the circular loop through a blockchain network. A mobile application user interface is provided to all the stakeholders for the ease of adoption. The batteries manufactured and supplied in a geographical region as well as the recycled materials at the battery end-of-life are traced authentically. This architecture is expected to be useful for the battery manufacturers to improve their extended producer responsibility and support responsible consumption and production.

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The increasing pressures of environmental regulation and the introduction of new policy frameworks by various nations have accelerated the popularization of industrial solid waste management and recovery, underscoring the transition towards a circular economy. This paradigm shift emphasizes the importance of material recovery, reuse, and recycling of industrial waste to minimize environmental impact and enhance sustainability. Despite the availability of individual approaches for waste recovery, there exists a significant gap in the systematic selection of optimal recovery pathways that facilitate the reintegration of materials into the production cycle. Addressing this gap, our study introduces a novel optimization model designed to identify the most efficient material circularity routes that leverage both the technical and biological cycles of the circular economy framework. Utilizing the Genetic Algorithm optimization tool in MATLAB, our model prioritizes pathways that maximize material recovery and profit generation simultaneously. This dual-objective function serves as the cornerstone of our analysis, ensuring a balanced approach to environmental sustainability and economic viability. The model's efficacy was tested on pre-calculated quantities of fabric waste generated by the Biyagama Export Processing Zone, providing a practical case study for its application. Our findings reveal diverse scenarios under which the model can allocate varying weights to each objective, demonstrating its flexibility and utility as a decision-making tool for stakeholders in the waste management sector. The results indicate that the model is not only capable of optimizing waste circularity pathways for maximum material recovery and profit generation but also offers a customizable framework that can adapt to the specific priorities of different stakeholders. This research contributes to the existing body of knowledge by filling a critical gap in the selection of sustainable waste recovery pathways, offering a practical, optimized, and scalable solution that can significantly advance the goals of the circular economy in the industrial sector.•Decision-making model for stakeholders in the waste management sector.•Model selects the best material recovery pathways.•Textile industrial fabric waste stream used as a pilot to test the model's effectiveness.

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This review is devoted to the English- and Russian-language terminology of quantitative metrics that are used in the evaluation of images obtained by optical coherence tomography angiography (OCT-A). The paper presents an analysis of the use of terms characterizing intraretinal blood flow (vascular density, perfusion density, skeletonized density, etc.), area and shape of the foveal avascular zone, and choriocapillaris blood flow. The factors causing the heterogeneity of OCT-A terminology are described, including the lack of a unified international nomenclature for OCT-A, features of their Russian translation, inconsistency of the parameters in optical coherence tomography systems of different manufacturers. The article also considers ways to standardize the terminology.

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The ultrasonic-assisted manufacturing process is a promising machining approach for composite materials as it exerts less force, making it ideal for the aerospace and automotive sectors. This work reports about the pre-crack initiation in carbon fiber reinforced (CF)/ poly-ether-ether-ketone (PEEK) composite under ultrasonic frequency at room temperature. An iron-based cutting tool matching the system's resonance frequency (20 kHz) was used to perform the ultrasonic pre-cracking. In this novel work, the pre-cracking of CF-PEEK is considered as the initial step for a complete fiber layer separation, which holds the key for circularity options in high-performance aerospace composites. State-of-the-art high-speed camera and infrared thermography were combined to monitor the crack initiation and propagation. By online monitoring, the different stages involved in the pre-cracking process, its temperature evolution, and consequently the dissipated energy during pre-cracking under ultrasonic frequency were evaluated. The results showed that oscillation amplitude had a significant influence on the determined pre-crack depth and measured global temperature and energy compared to cutting force. The measured global temperature data indicates that pre-cracking occurred in the solid state with a temperature well below the glass-transition temperature of PEEK. However, the local temperature at the contact between the sample and sonotrode could have been much higher during ultrasonic cutting which needed further investigation. The computed global dissipated energy and temperature were only reliable at the pre-crack initiation site due to the limitation in the infrared thermography system.

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Despite the increasing popularity of the circular economy, there remains a lack of consensus on how to quantify circularity, a critical aspect of the practical implementation of this model. To address this gap, this article examines the industry's perspective and efforts toward implementing the circular economy in real-world scenarios. We conducted 40 interviews with engineers, project leaders, and top-level managers in the Australian construction sector. Using Saldaña's coding approach, we analysed their views on circular economy practices and efforts within their organisations. Our findings reveal while waste minimisation, reduction of greenhouse gas emissions, and cost considerations are widely regarded as essential indicators of a successful circular economy model, the significance of waste storage and long-term stockpiling while awaiting treatment has been overlooked or under-emphasised in industry practices and academic literature. Stockpiling of waste has often been seen as a staging process in waste treatment. However, based on industry insights, it accumulates to the point of mismanagement when it becomes a safety and environmental concern. Addressing this oversight, we propose a storage circularity indicator that allows incorporating waste storage and stockpiling in circular economy models. Our research contributes to various environmental and waste management aspects, supporting policies and strategies for solid waste management and excessive stockpile prevention. By emphasising the significance of storage circularity, we clarify waste prevention techniques and address socio-economic issues such as the urgent need to reduce long-term stockpiling of solid waste. This work highlights the importance of decision-support tools in waste management to facilitate the implementation of circular economy principles. Our proposed storage circularity indicator promotes industrial collaboration, aligning with the concept of industrial symbiosis to optimise resource use and minimise waste generation. By discussing these topics, we aim to contribute to the advancement of more robust waste management strategies and policies that promote sustainable production and consumption practices.

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Black soldier fly larvae (Hermetia illucens; BSFL) can transform organic wastes into nutritional biomass useful in animal feeding. The aim of this work was to study the effect of five diets (meat, fruit, vegetable substrates, a mix of them and control) on the profile of fatty acids (FAs) and sterols of BSFL. For a more exhaustive characterization of the nutritional properties, the profile of esterified FAs in the sn-2 position of the triglycerides, the most absorbed lipid component during animal digestion was evaluated. The dietary effect was estimated on two different Hermetia illucens populations (Greek - UTH and Italian - UNIPI). The diet affected all the lipid fractions examined. Regardless of diet, the fat was characterized mainly of lauric acid and other saturated FAs, which were found to be synthesized by the larvae, as it was not present in any of the five substrates. In general, UTH larvae contained a higher level of lipids (7.38 vs 2.48 g/100 g of larvae; P < 0.001) and saturated FAs (49.71 vs 36.10 g/100 g of Total Lipids; P < 0.001) and a lower percentage of monounsaturated FAs (14.74 vs 26.70 g/100 g of Total Lipids), C18:3n-3 (0.67 vs 1.13 g/100 g of Total Lipids; P < 0.001), and C18:2c9t11 (2.02 vs 2.80 g/100 g of Total Lipids; P < 0.001). Irrespective of the populations, BSFL reared on control and fruit substrates showed higher level of lipids (8.06 and 5.61 g/100 g of larvae, respectively), and saturated FA (38.99 and 71.19 g/100 g of Total Lipids, respectively), while the presence of meat increased the level of C20:4n-6, C20:5n-3 and C22:5n-3 (0.70, 0.13 and 0.45 g/100 g of Total Lipids, respectively). The results confirmed that BSFL accumulate phytosterols in their lipid fraction. The sterol profile was strongly influenced by the substrate on which the larvae were reared, with higher levels of cholesterol in the larvae of the meat group (38.55 mg/100 g of Total Lipids) and of stigmasterol and campesterol (9.04 and 15.23 mg/100 g of Total Lipids, respectively) in those of the vegetable group. The sterol content between the two populations was significantly different, with a higher percentage in UTH larvae (113.28 vs 34.03 mg/100 g of Total Lipids; P < 0.001). Finally, BSFLs showed a high plasticity of the lipid profile depending on both the substrate and the metabolism linked to the different populations. This variability allows the nutritional characteristics of the BSFL to be shaped by modifying the substrate, to adapt it to the technological and feeding needs to which the larvae are destined.

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Restoring nutrient circularity across scales is important for ecosystem integrity as well as nutrient and food security. As such, research and development of technologies to recover plant nutrients from various organic residues has intensified. Yet, this emerging field is diverse and difficult to navigate, especially for newcomers. As an increasing number of actors search for circular solutions to nutrient management, there is a need to simplify access to the latest knowledge. Since the majority of nutrients entering urban areas end up in human excreta, we have chosen to focus on human excreta and domestic wastewater. Through systematic mapping with stakeholder engagement, we compiled and consolidated available evidence from research and practice. In this paper, we present 'Egestabase' - a carefully curated open-access online evidence platform that presents this evidence base in a systematic and accessible manner. We hope that this online evidence platform helps a variety of actors to navigate evidence on circular nutrient solutions for human excreta and domestic wastewater with ease and keep track of new findings.

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Globally, the circular efficiency of biomass resources has become a priority due to the depletion and negative environmental impacts of fossil fuels. This study aimed to quantify the atmosphere-dependent combustion of Ganoderma lucidum (GL) biomass and its thermodynamic and kinetic parameters toward enhancing its circularity and transformability characteristics. The GL combustion occurred in the three stages of moisture removal, volatile release, and coke combustion. Combustion performance characteristics were more favorable in the N2/O2 atmosphere than in the CO2/O2 atmosphere under the same heating rates. The rising heating rate facilitated the release of volatiles. According to the model-free methods of Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose, the activation energies essential for the primary reaction were 283.09 kJ/mol and 288.28 kJ/mol in the N2/O2 atmosphere and 233.09 kJ/mol and 235.64 kJ/mol in the CO2/O2 atmosphere. The gaseous products of the GL combustion included CH4, H2O, C = O, CO, CO2, NH3, C = C, and C-O(H). Ash prepared in both atmospheres exhibited a tendency for slag formation, with oxy-fuel combustion lowering its risk. This study thus provides a theoretical and practical basis for transforming GL residues into a sustainable energy source.

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The black soldier fly larva, Hermetia illucens, can efficiently convert organic waste into biomatter for use in animal feed. This circularity comes with a risk of contaminating downstream consumers of the larval products with microbes, heavy metals, and other hazards potentially present in the initial substrate. This review examines research on mitigation techniques to manage these contaminants, from pretreatment of the substrate to post-treatment of the larvae. While much research has been done on such techniques, little of it focused on their effects on food safety contaminants. Cheap and low-technology heat treatment can reduce substrate and larval microbial load. Emptying the larval gut through starvation is understudied but promising. Black soldier fly larvae accumulate certain heavy metals like cadmium, and their ability to process certain hazards is unknown, which is why some government authorities are erring on the side of caution regarding how larval bioconversion can be used within feed production. Different substrates have different risks and some mitigation strategies may affect larval rearing performance and the final products negatively, so different producers will need to choose the right strategy for their system to balance cost-effectiveness with sustainability and safety.

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A common justification for abortion rights is that the death of the fetus does not violate any of the fetus's time-relative interests. The time-relative interest account (TRIA) of harm and wrongdoing tells us that a necessary condition for harming someone is that his or her time-relative interests are frustrated. Regarding the justification for abortion, this account falls prey to impairment arguments. Impairment arguments entertain cases of prenatal injury, such as the mother using illicit drugs that disable the child. The intuition is that the child who is born with such disabilities is harmed by the mother's drug use. But it is unclear what time-relative interest is violated in cases of prenatal harm. Typical responses to impairment arguments point out that the abortion case is different because the child does not exist to experience such harms; but in prenatal injury + survival cases, the child does live to experience those harms. Thus, the TRIA justification for abortion is not impugned by impairment counter-examples. This article argues that this response to impairment arguments is viciously circular. The response must say that so long as you kill the child, no harm is done. But this assumes that killing itself is morally inconsequential and is not itself a case of harm. The response to impairment arguments, then, assumes the permissibility of abortion.

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Recently, much research has been oriented towards the influence of different food wastes and agricultural by-products on the final larval biomass and chemical composition of the insect species Hermetia illucens L. (Diptera: Stratiomyidae). However, there is a gap in the literature regarding the possible relationship between the feeding substrate of H. illucens larvae and chitin. In this context, in the present study, larvae of H. illucens derived from two populations (i.e., UNIPI and UTH), were reared on different diets composed of fruits, vegetables, and meat. Based on the results, the larval survival was high for all diets tested. Larval growth in terms of weight gain, larval length, and feed conversion ratio (FCR) depended on the composition of each diet. The chitin and chitosan composition of larvae, reared on different substrates, did not reveal significant differences. Given the fact that the feeding substrate represent a significant cost in the industrial production of insects, its correlation with a high value product (i.e. chitosan) is important. On the other hand, as the prepupal stage of H. illucens is currently used as animal feed, the metabolization of chitin by farmed animals when the larvae or prepupae were offered as feed could have adverse effects. Thus, depending on the final product that is to be produced, industries could benefit from the establishment of a suitable diet.

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Countries' circularity performance and CO2 emissions should be addressed as a part of the UN net-zero Sustainable Development Goals (SDGs) 2030. Macro-scale circularity assessment is regarded as a helpful tool for tracking and adjusting nations' progress toward the sustainable Circular Economy (CE) and SDGs. However, practical frameworks are required to address the shortage of real-world circularity assessments at the macro level. The establishment of CE benchmarks is also essential to enhance circularity in less sustainable nations. Further, monitoring the extent to which nations' circularity activities are sustainable and in line with the SDGs is an area that lacks sufficient practical research. The current research aims to develop a macro-level framework and benchmarks for national sustainable circularity assessments. Methodologically, we develop a dynamic network data envelopment analysis (DN-DEA) framework for multi-period circularity and eco-efficiency assessment of OECD countries. To do so, we incorporate dual-role and bidirectional carryovers in our macro-scale framework. From a managerial perspective, we conduct a novel comparative analysis of the circularity and eco-efficiency of the nations to monitor macro-scale sustainable CE trends. Research results reveal a significant performance disparity in circularity, eco-efficiency, and benchmarking patterns. Accordingly, circularly efficient nations cannot necessarily be considered eco-friendly and sustainable. Although Germany (as a superior circular nation) can be regarded as a circularity benchmark, it cannot serve as an eco-efficiency benchmark for less eco-efficient nations. Hence, the new method allows decision-makers not only to identify the nations' circularity outcome but also to distinguish sustainable nations from less sustainable ones. This, on the one hand, provides policymakers with a multi-faceted sustainability analysis, beyond the previous unidimensional analysis. On the other, it proposes improvement benchmarks for planning and regulating nations' future circularity in line with real sustainability goals. The capabilities of our innovative approach are demonstrated in the case study.

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Low-density polyethylene (LDPE), extensively employed in flexible plastic packaging, often undergoes printing with inks. However, during the mechanical recycling of post-consumer waste, these inks act as contaminants, subsequently compromising the quality and usability of recycled material. To understand better exactly which ink components cause which effects, this study comprehensively assesses the thermal behavior of three organic pigments and two commonly utilised binders, correlated with the impact on the mechanical recycling of LDPE-based flexible plastic packaging. In this regard, the study focuses on four pivotal factors: processability, mechanical properties, aesthetic attributes, and volatile organic compound profiles. The results indicate that nitrocellulose, used as a binder, degrades during reprocessing, resulting in film discoloration and the emission of potentially odorous compounds. Conversely, pigments are found to be dispersed within droplets of polyurethane binder in LDPE recyclates, whilst reprocessing printed samples detrimentally affects film properties, notably dart drop impact resistance, strain at break, and the number of inclusions. Additionally, it is shown that both inks comprise components that emit volatile compounds during reprocessing: non-thermally stable components, nitrocellulose and pigment yellow PY13, as well as low-molecular weight molecules from polyurethane and by-products from wax, plasticisers, and additives.

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In 2021, an Australian research centre partnered with a regional marina and shipyard where 90 businesses build, refit, and maintain boats in premium condition. Tenants and owners grapple with environmental waste management issues. Since there is a gap in applying action research but numerous calls to co-produce solutions and participate in translating ideas into practice, action research was used in this case study involving upstream and downstream innovation for circularity. Mixed methods data was collected through interviews, stakeholder workshops, and waste audits. A strategic action plan was created for closing the loop on waste. Interventions included tackling toxic, degradable products with natural alternatives, trading and remanufacturing materials to extend product life cycles, testing problematic materials, and pursuing product stewardship. This study is novel because it extends diffusion of innovation theory to real-world impact through a co-innovation process. Results underscore that ongoing achievements depend on properly sorting waste, accessing reprocessing facilities, and maintaining dedicated staff and partnerships, especially legislative support for making continuous improvement.

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