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This study aimed to investigate the sustainable use of recycled plastics, specifically polypropylene (PP) and high-density polyethylene (HDPE), in the manufacture of geogrids for geotechnical and civil engineering applications. Plastics were collected from a recycling center, specifically targeting containers used for food, cleaning products, and other domestic packaging items. These plastics were sorted according to the Möbius triangle classification system, with HDPE (#2) and PP (#5) being the primary categories of interest. The research methodologically evaluates the mechanical properties of PP/HDPE (0/100, 25/75, 50/50, 75/25 and 100/0% w/w) composites through tensile and flexural tests, exploring various compositions and configurations of geogrids. The results highlight the superiority of pure recycled HDPE processed into 1.3 mm thick laminated yarns and hot air welded for 20 to 30 s, exhibiting a deformation exceeding 60% in comparison to the PP/HDPE composites. Through SolidWorks® Simulation, it was shown that the adoption of a trigonal geogrid geometry optimizes force distribution and tensile strength, significantly improving slope stabilization efficiency. Based on the results obtained, a laboratory-scale prototype geogrid was developed using an extrusion process. The results underscore the importance of careful composite design and yarn configuration selection to achieve the desired mechanical properties and performance in geogrid applications. It emphasizes the potential of recycled plastics as a viable and environmentally friendly solution for stabilizing slopes, contributing to the reduction in plastic waste and promoting sustainable construction practices. [ABSTRACT FROM AUTHOR]

This study demonstrates a novel methodology for developing a textile-based adsorption sensor via mixed solvent dyeing with aggregation-induced emission (AIE) dyes on recycled fabrics. AIE dyes were incorporated into the fabrics using a mixed solvent dyeing method with a co-solvent mixture of H2O and organic solvents. This method imparted unique fluorescence properties to fabrics, altering fluorescence intensity or wavelength based on whether the AIE dye molecules were in an isolated or aggregated state on the fabrics. The precise control of the H2O fraction to organic solvent during dyeing was crucial for influencing fluorescence intensity and sensing characteristics. These dyed fabrics exhibited reactive thermochromic and vaporchromic properties, with changes in fluorescence intensity corresponding to variations in temperature and exposure to volatile organic solvents (VOCs). Their superior characteristics, including a repetitive fluorescence switching property and resistance to photo-bleaching, enhance their practicality across various applications. Consequently, the smart fabrics dyed with AIE dye not only find applications in clothing and fashion design but demonstrate versatility in various fields, extending to sensing temperature, humidity, and hazardous chemicals. [ABSTRACT FROM AUTHOR]

The global composite industry generates large quantities of waste which mostly ends up in landfills due to a lack of established end-use applications for multiple waste streams. The scrap from end-of-life (EoL) includes manufacturing waste such as dry chopped fiber tows, loose fibers, shredded fibers from fabric textile operations, cured/semi-cured prepregs, and fully cured composite structure waste from aircraft, automobiles, wind blades, boats, and pressure vessels. In this work, different composite waste streams were reduced to shredded intermediates, followed by simple blending, and subjected to wet compression molding to produce composite panels. The panels/plaques were tested for mechanical properties (flexure and impact), fiber-matrix wet-out, and property bounds. It was found that wet-compression molding was a viable and scaleable approach to produce recycled panels from EoL composites shredded scrap. Furthermore, full-scale size panels for use in truck bodies and intermodal shipping container flooring were manufactured and their impact resistance was tested using a drop weight impact test. They were tested both for high- and low-velocity load. In the case of high-velocity load, the average impact load was 14,673 N; the average absorbed energy was 101.6 J; the average elastic energy was 11.7 J and the impact resistance was 1065 J/m. In the case of the low-velocity drop weight impact test, it was found that the average impact load was 7877.358 N; the average absorbed energy was 9.718 J; the average elastic energy was 9.14 J, and the impact resistance was 184.1 J/m. The shredded composite was shown to be a candidate material for the manufacture of truck bodies and intermodal containers' flooring panels. Highlights • By using shredded intermediates from different composite waste streams, it is possible to manufacture composite panels. • Wet-compression process is an appropriate technique for manufacturing recycled fiber composite panels. • Regardless of the source of scrap, the mechanical properties of the produced composite panels were improved. • The recycling process technology can be transformed to commercial scale to produce full-size transportation flooring panels. • A product pathway is established in consideration of lower cost and improved recyclability. [ABSTRACT FROM AUTHOR]

The temperatures of the phase transitions for polyethyleneterephthalate samples containing recycled PET (the product Vivilen) and the waste materials from its production were analyzed by differential scanning calorimetry and x-ray structural analysis, and the ratio of the crystalline and amorphous phases was determined. The polyethyleneterephthalate samples were arranged according to their glass transition and melting points, which made it possible to correlate the samples according to the degree of crystallinity. In order to obtain a filament based on the dust waste from the solid-phase polycondensation process an extrusion temperature regime was established, and samples of filaments for 3D printing that meet the requirements of GOST R 59100-2020 were obtained. [ABSTRACT FROM AUTHOR]

The present study focuses on the innovative technique for making rectangular and circular hollow concrete blocks using fly ash (FA) and recycled concrete aggregates (RCA). The feasibility of employing RCA in conjunction with fly ash as a substitute for natural aggregates and cement in a proportion ranging from 30%–90% and 15%–45%, respectively, is tested in the laboratory. According to current standards, the tests comprise the slump test, compressive strength test, water absorption test, and structural efficiency evaluation. An empirical quantitative technique is used for the cost–benefit analysis of a 100-square-foot model built with recycled concrete hollow blocks. The study suggests that employing recycled concrete aggregate and fly ash as replacements for conventional materials would result in a minimum cost savings of 17%. The quantity of greenhouse gases produced in CO2 equivalents during concrete production is calculated using the Inventory of Carbon and Energy database. According to research findings, the utilization of recycled concrete aggregates and fly ash reduced carbon dioxide equivalent emissions by 30%–40%. It was also confirmed that cement has a major effect on greenhouse gas emission generation throughout the concrete manufacturing phase, regardless of the use of RCA over virgin aggregates. This study intends providing a significant understanding of how RCA and FA can not only contribute to environmental conservation but also offer economic benefits. Finally, the research intends to encourage the adoption of ecologically responsible and economically viable sustainable practices in the construction industry. [ABSTRACT FROM AUTHOR]

Soil thixotropy plays an important role in many engineering practices, which recently has been drawn an increasing attention by many researchers. In this paper, an experimental investigation on the thixotropy of deepwater marine clays in the South China Sea was carried out. The thixotropy-induced changes of undrained shear strength were measured by fall cone method, and the microscale evolution of soil structure, particularly the change of various types of water, was observed and quantified via employing scanning electron microscopy and thermogravimetric analysis, respectively. The test results show that the thixotropy strength ratios of all deep-sea clays increase quickly at the early stage (before about 10 days), then followed by a gradually lower increasing rate with prolonged time. The microstructural evolution of clay during thixotropic hardening is characterized by the transformation from a dispersed structure with parallel-arranged particles to a well flocculated one. The different types of water and their changes of mass fraction with thixotropic time could be well classified and quantitatively measured by thermogravimetric analysis, in which both the weakly and strongly bound water contents decrease, with the corresponding increase in the free water fraction. The thixotropic mechanism was then revealed from the perspective of the microstructural evolution and the adjustment of the thickness of bound water. The recovery of strength is majorly attributed to the forming and strengthening of inter-particle bonds or contacts and the adjustment of bound water layer. This research could help to provide a deeper insight into the inner reason of soil thixotropy. [ABSTRACT FROM AUTHOR]

The reasonable location of treatment plants can improve the recovery rate of construction and demolition waste (C&DW). However, most studies ignore the impact of uncertainty or are based on known probability information. This study establishes an optimization site selection model using a robust method, which takes into account the uncertainty of the recycling amount of C&DW and the demand for recycled products. The immune genetic algorithm is applied to solve and analyse the model. Chongqing, the only municipality in south-west China, is taken as a case study. The results show that: (1) transportation costs affect the behaviour of construction contractors in recycling C&DW; (2) site selection schemes and total costs vary with changes in the disturbance ratio and uncertainty level, and the uncertainty of supply has a greater impact on the costs; and (3) when the uncertainty level and disturbance rate reach a certain value, the site selection scheme changes. [ABSTRACT FROM AUTHOR]

Special attention to the Agri-food closed-loop supply chain is more critical during global crises, such as the COVID-19 pandemic. The main reason for this issue is the importance of food security in different communities during various crises. On the other hand, strategic analysis helps Agri-food organizations to be more prepared to face threats and use the opportunities of these crises. Consequently, the combination of supply chain management and strategic analysis can be utilized for better planning in this situation. In the present study, the closed-loop supply chain of canned food in uncertain conditions is investigated. One of the main features of the problem is to use the canned food waste to increase profitability during the COVID-19 pandemic. In addition, the Robust Probabilistic Chance Constrained Programming (RPCCP) approach is presented to face the uncertainty of the problem. One of the main features of the approach is to determine the confidence level of the system proactively to add the concept of robustness to the problem. After using the combined approach and prioritizing strategies for the case study from an emerging economy, "Increased export share of canned food products through virtual marketing and exhibitions" was selected as the superior strategy during the COVID-19 pandemic. Based on the comparison of the results with the organization's current conditions, it was found that the income from the sales of primary products and recycled products increased by 39.8% and 10.79%, respectively. Implementing this strategy indicated that the values of other essential criteria of the closed-loop supply chain also increased. [ABSTRACT FROM AUTHOR]

Methylenedianiline (MDA) is a secondary, undesired, product of the glycolysis process of polyurethane (PU) scraps due to hydrolysis and pyrolysis side reactions. As an aromatic and carcinogen amine, MDA poses different problems in handling, transporting, and labelling recycled polyols derived from glycolysis, hindering the closure of PU recycling loop. Aiming to provide a solution to this issue, in this work different deaminating agents (DAs) were investigated with the purpose of analyzing their reactivity with MDA. A first part of the study was devoted to the analysis of MDA formation as a function of reaction time and catalyst concentration (potassium acetate) during glycolysis. It was observed that the amount of MDA increases almost linearly with the extent of PU depolymerization and catalyst content. Among the DAs analyzed 2‐ethylhexyl glycidyl ether (2‐EHGE), and acetic anhydride (Ac2O) showed interesting performance, which allowed MDA content to be diminished below the limit for labelling prescription in 30 minutes. PU rigid foams were, therefore, synthesized from the corresponding recycled products and characterized in terms of thermal and mechanical performance. Ac2O‐deaminated polyols led to structurally unstable foams with poor compressive strength, while 2‐EHGE‐deaminated products allowed the production of foams with improved mechanical performance and unaltered thermal conductivity. [ABSTRACT FROM AUTHOR]

Elevated concentrations of phosphorus (P) and other nutrients common in wastewater treatment plant (WWTP) effluent have been shown to contribute to the proliferation of harmful algal blooms, which may lead to fish kills related to aquatic hypoxia. Increased understanding of the negative effects associated with elevated P concentrations have prompted more strict regulation of WWTP effluent in recent years. The use of low‐cost and potentially regenerative adsorptive phosphate filters has the potential to decrease P concentrations in WWTP effluent released to natural waters. This research focuses on assessing the capacities of recycled concrete aggregate (RCA), expanded slate, and expanded clay to remove phosphate from P‐amended WWTP effluent. Results from a flow‐through column study indicate that RCA consistently removed an average of 97% of phosphate over 20 weeks of continuous flow at an 8‐hour hydraulic retention time (HRT). Expanded clay removed an average of 63% of introduced phosphate but decreased in removal capacity from 91 to 42% over the 20‐week duration. Sorption data from batch studies were fitted to Langmuir models and RCA was shown to have the highest maximum sorption capacity (6.16 mg P/g), followed by expanded clay (3.65 mg P/g). RCA and expanded clay are promising options for use in passive filters for further reduction of phosphate from WWTP effluent. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) is the most widely produced synthetic polymer. By installing chemically cleavable bonds into the backbone of PE, it is possible to produce chemically deconstructable PE derivatives; to date, however, such designs have primarily relied on carbonyl‐ and olefin‐related functional groups. Bifunctional silyl ethers (BSEs; SiR2(OR′2)) could expand the functional scope of PE mimics as they possess strong Si−O bonds and facile chemical tunability. Here, we report BSE‐containing high‐density polyethylene (HDPE)‐like materials synthesized through a one‐pot catalytic ring‐opening metathesis polymerization (ROMP) and hydrogenation sequence. The crystallinity of these materials can be adjusted by varying the BSE concentration or the steric bulk of the Si‐substituents, providing handles to control thermomechanical properties. Two methods for chemical recycling of HDPE mimics are introduced, including a circular approach that leverages acid‐catalyzed Si−O bond exchange with 1‐propanol. Additionally, despite the fact that the starting HDPE mimics were synthesized by chain‐growth polymerization (ROMP), we show that it is possible to recover the molar mass and dispersity of recycled HDPE products using step‐growth Si−O bond formation or exchange, generating high molecular weight recycled HDPE products with mechanical properties similar to commercial HDPE. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) is the most widely produced synthetic polymer. By installing chemically cleavable bonds into the backbone of PE, it is possible to produce chemically deconstructable PE derivatives; to date, however, such designs have primarily relied on carbonyl‐ and olefin‐related functional groups. Bifunctional silyl ethers (BSEs; SiR2(OR′2)) could expand the functional scope of PE mimics as they possess strong Si−O bonds and facile chemical tunability. Here, we report BSE‐containing high‐density polyethylene (HDPE)‐like materials synthesized through a one‐pot catalytic ring‐opening metathesis polymerization (ROMP) and hydrogenation sequence. The crystallinity of these materials can be adjusted by varying the BSE concentration or the steric bulk of the Si‐substituents, providing handles to control thermomechanical properties. Two methods for chemical recycling of HDPE mimics are introduced, including a circular approach that leverages acid‐catalyzed Si−O bond exchange with 1‐propanol. Additionally, despite the fact that the starting HDPE mimics were synthesized by chain‐growth polymerization (ROMP), we show that it is possible to recover the molar mass and dispersity of recycled HDPE products using step‐growth Si−O bond formation or exchange, generating high molecular weight recycled HDPE products with mechanical properties similar to commercial HDPE. [ABSTRACT FROM AUTHOR]

This article introduces a one-step extrusion-based fused deposition modeling (FDM) approach for the challenging separation of polypropylene (PP) and polyethylene terephthalate (PET) during recycling. A shear screw printer (SSP) with shear elements was designed, and it was compared to a conventional single-screw printer (CSP) to investigate the differences in print stability, degradation levels, tensile performance, molecular orientation, and crystallization when preparing recycled PP and recycled PET blends. Although the retention effect of the SSP screw slightly increases the degradation of the blended rPP/rPET, the strong shear (2.6 × 104 s−1) applied near the extrusion exit improves the blending efficiency. The SSP also enhances molecular orientation, modulus of the parts, and reduces performance fluctuations. Additionally, the SSP has the potential to simplify the recycling process, enabling the transformation of blended recycled materials into products with just one melt process. [ABSTRACT FROM AUTHOR]

Mixed plastic waste recycling represents a significant challenge as the phase separation of different components dictates downgraded performance. Polymer‐based compatibilizers can offer a promising solution to address this issue, through effectively reducing surface tension and increasing interfacial strength between distinct components to result in improved mechanical and thermal properties of recycled products. This perspective provides an overview of the fundamental concepts for the rational design of copolymer blend compatibilizers and discusses their recent advances, including both preformed and in situ generated systems. Impacts of key material parameters of compatibilizers, such as chain topology, chemical composition, and block sequence on their performance of remediating mixed plastics are discussed. Additionally, reactive compatibilization strategies are also introduced, including in situ formation of polymers, installing functional groups on mixed plastics, and employing dual compatibilization strategies. Looking forward, there are many research and technology opportunities in this area, especially for enabling the use of blend compatibilizers to practically address mixed plastic wastes at scale. Specifically, future compatibilizer design and application should provide strong competitiveness in both cost and energy savings, and carbon emission reduction. Together, the development of blend compatibilizers is an important step in establishing plastic circular economy and creating a more sustainable future. [ABSTRACT FROM AUTHOR]

Over the years, the demands on the durability and quality of polyester fabrics used for sportswear have increased, as these fabrics contribute to athletes' performance. At the same time, the use of recycled polyester material is increasingly being promoted for environmental reasons. This study focused on investigating the properties of standard and recycled polyester fabrics before and after aging according to the developed aging protocol. The surface morphology, thickness, elongation at break, force at break, bursting force, mass loss due to abrasion and moisture management of the fabrics were tested. The results showed that the aging process had no influence on the surface changes in the fabrics. More specifically, there were neither surface cracks on the fibre surface nor chemical changes. The highest decrease in force at break for standard polyester fabrics with elastane was up to 26%, and up to 15% for fabrics made of recycled polyester. The loss of mass due to abrasion was greater for recycled polyester than for standard polyester fabrics. The average ability of the fabrics to absorb moisture decreased by up to 23% after aging, while the wetting time increased by up to 30%, with the highest increase observed in recycled fabrics. [ABSTRACT FROM AUTHOR]

This research analyses how different cement mortars behave in terms of their physical and mechanical properties. Several components were necessary to make seven mixes of mortars, such as Portland cement, standard sand, and solid waste from a factory of sodium silicate, in addition to graphene oxide. Furthermore, graphene oxide (GO) was selected to reduce the micropores and increase the nanopores in the cement mortar. Hence, some tests were carried out to determine their density, humidity content, water absorption capacity, open void porosity, the alkali–silica reaction, as well as flexural and mechanical strength and acid resistance. Thus, standard-sand-manufactured mortars' mechanical properties were proved to be slightly better than those manufactured with recycled waste; the mortars with this recycled aggregate presented problems of alkali–silica reaction. In addition, GO (in a ratio GO/cement = 0.0003) performed as a filler, improving the mechanical properties (30%), alkali–silica (80%), and acid resistance [ABSTRACT FROM AUTHOR]

Purpose: Because of the anisotropy of the process and the variability in the quality of printed parts, finite element analysis is not directly applicable to recycled materials manufactured using fused filament fabrication. The purpose of this study is to investigate the numerical-experimental mechanical behavior modeling of the recycled polymer, that is, recyclable polyethylene terephthalate (rPET), manufactured by a deposition FFF process under compressive stresses for new sustainable designs. Design/methodology/approach: In all, 42 test specimens were manufactured and analyzed according to the ASTM D695-15 standards. Eight numerical analyzes were performed on a real design manufactured with rPET using Young's compression modulus from the experimental tests. Finally, eight additional experimental tests under uniaxial compression loads were performed on the real sustainable design for validating its mechanical behavior versus computational numerical tests. Findings: As a result of the experimental tests, rPET behaves linearly until it reaches the elastic limit, along each manufacturing axis. The results of this study confirmed the design's structural safety by the load scenario and operating boundary conditions. Experimental and numerical results show a difference of 0.001–0.024 mm, allowing for the rPET to be configured as isotropic in numerical simulation software without having to modify its material modeling equations. Practical implications: The results obtained are of great help to industry, designers and researchers because they validate the use of recycled rPET for the ecological production of real-sustainable products using MEX technology under compressive stress and its configuration for numerical simulations. Major design companies are now using recycled plastic materials in their high-end designs. Originality/value: Validation results have been presented on test specimens and real items, comparing experimental material configuration values with numerical results. Specifically, to the best of the authors' knowledge, no industrial or scientific work has been conducted with rPET subjected to uniaxial compression loads for characterizing experimentally and numerically the material using these results for validating a real case of a sustainable industrial product. [ABSTRACT FROM AUTHOR]

The article focuses on the recycled materials used in sleeper substructure. In the introduction, it summarizes the requirements for bearing layers of railway substructure and recycling of waste construction materials. The article presents the materials on which laboratory tests have been carried out and discusses in detail the most perspective - recycled concrete. For concrete recyclate, the article describes the results of laboratory tests - sieve analysis, determination of optimum moisture, and determination of bearing capacity using California bearing ratio, Immediate bearing index and Static deformation modulus. [ABSTRACT FROM AUTHOR]

In this work, a novel method for a more sustainable recycling and cost-efficient manufacturing technique of polyether ketone ketone (PEKK) based thermoplastic composite materials is proposed to recover and reprocess waste and end-of-life materials in the aerospace industry. For the recycling of carbon fiber reinforced thermoplastics (CFrTP), an innovative scrapping process based on mechanical cutting was developed and the properties of the obtained scrap and the recycled panel were analyzed. Thus, a cutting tool was developed for the delamination of the input material so that long fibers can be retained in the resulting scrap. Different processing approaches of material scrapping were evaluated, aiming to obtain manageable scrap that can be subsequently used for a compression molding process. Additionally, an automatic process was evaluated to manage the scrap and perform the corresponding lay-up to manufacture high-quality thermoplastic composite products with recycled materials. [ABSTRACT FROM AUTHOR]

The current soaring market for lithium-ion batteries (LIBs) in energy storage devices has promoted the recycling and utilization of secondary resources, including retired LIBs. However, current recycling technologies are confronted with numerous deficiencies in balancing extraction efficiency, energy consumption, emissions, and profit. Here, we propose a well-designed thermal oxidation strategy for pyro-process-based Li extraction from spent LiFePO4 (S-LFP), which involves the application of a molten sulfate infiltration–oxidation synergistically controlled reaction occurring at a low temperature (300 °C) and constitutes a one-step preparation with high lithium recovery (>99%) and a high-value iron phosphate (FPO) product. The regenerated LiFePO4 (R-LFP) materials as recycled products exhibit an excellent discharge capacity (136.2 mA h g−1 at 1C) and cycling stability (98.9% capacity retention after 100 cycles). The economic analysis verifies a profit increase of 155% per kilogram and an emission decrease of 216% for this strategy compared with traditional hydrometallurgical processes. The proposed approach is particularly appealing due to its high profit, industrial feasibility, and environmental benefits. [ABSTRACT FROM AUTHOR]

Although the consequences of adhesive residues from post-consumer Poly(ethylene terephthalate) (PET) beverage bottles on the performance of recycled products are known, the quantitative effects of these adhesives are not well-stablished in the literature. Therefore, these residues were determined by gravimetry, and the adhesive content range from 200 to 2800 ppm in post-consumer PET bottles, depending on the drink filled. Through FTIR analysis, it was determined that the adhesives for bottles labelling are composed by poly(ethylene- co -vinyl acetate) (EVA). Based on these results, recycled PET with 0, 200, 700, 1500 and 3000 ppm of hot-melt EVA were processed in an internal mixer connected to a torque rheometer at 265°C for 10 min. Tensile tests indicate that 200 ppm of adhesive reduced PET tensile strength by 15%. Furthermore, when about 1500 ppm of adhesive is present, PET mechanical properties are reduced by 50%. Therefore, it is of utmost importance to warn the PET bottle production chain to reduce adhesive content used in labelling so that it should not exceed 200 ppm, if a high quality recycled PET is desirable. Graphical Abstract [ABSTRACT FROM AUTHOR]

The steel industry in Taiwan produces more than 3 million tons of steelmaking slag per year on average. Conventional solidification and landfilling methods are no longer suitable for the highly populated small island as a wide area is needed for such methods. This study aims to improve the quality of polluted water bodies using desulfurization slag – a recycled product resulted from steelmaking – as an arsenate adsorbent. Experimental results revealed that desulfurization slag pH and metal ions including Ca, Mg, Fe, and Mn affected the behavior and content of arsenate existing in an aqueous solution. The concentration of Ca among these metal ions is the highest in the aqueous solution, which facilitates the formation of calcium hydroxyarsenate and is therefore more critically beneficial than other metal ions in removing As in the aqueous solution. Additionally, desulfurization slag samples with particle size of >200 mesh had a greater specific surface area compared to those in other particle sizes, suggesting preferable As adsorption ability of slag with higher mesh numbers. Such desulfurization slag samples were thus used in subsequent adsorption experiments in this study. The energy dispersive spectrometry results confirmed that the >200‐mesh group comprised the highest metal oxide content in terms of As removal. This study found that under different Cl− and SO42− concentrations, the covalent bond effect did not significantly affect the slag's ability to adsorb As. According to the adsorption isotherm experiment results, the Langmuir model (R2 = 0.998) outperformed the Freundlich model (R2 = 0.961) possibly because the former is suitable for situations with even energy distribution and monolayer adsorption, while the latter is often applied to scenarios with uneven distribution and multilayer adsorption, indicating that the adopted desulfurization slag adsorbed arsenate through the mechanism of monolayer adsorption. There are many useful contents in the desulfurization slag. In terms of sustainable use of resources, desulfurization slag is worthy of economic development and reusing if recycled. Currently, there is little research and information on desulfurization slag in Taiwan. Hopefully, this study will be helpful for future development and application of desulfurization slag in recycling techniques. [ABSTRACT FROM AUTHOR]

Improved economic growth and environmental protection are necessary to achieve the United Nations' Sustainable Development Goals. This study examines the relationship between people's education levels and sustainable lifestyles in protecting the environment and economic growth, as expressed by the increase in household equivalent income. We conducted an original cross-sectional survey, which yielded 100,956 valid observations in 37 countries. The factors included educational level, sustainable lifestyle with natural resource consumption, and household equivalent income for economic development. We used logit and ordered logit model and applied an ordinary linear regression model after confirming the association between education and income. Our analyses found that higher educational levels were associated with an increase in specific environmentally friendly behaviors and sustainable energy consumption. Individuals in the higher educational level group tended to consume recycled goods, purchase energy-saving household products, conserve electricity, and separate their waste. Additionally, higher levels of education were positively associated with equivalent household income in all 37 countries, indicating better economic development. Thus, our study underscores the importance of improving education at the broad population level to promote economic development and establish cooperative human behaviors necessary to sustain the environment. [ABSTRACT FROM AUTHOR]

Plastic materials have been widely used to replace metals in functional parts due to their lower cost and comparable technical properties. However, the increasing use of virgin plastic material in consumer and industrial applications has placed a significant burden on waste management due to the volume of waste created and the potential negative effects of its end-of-life processing. There is a need to adopt circular economy strategies such as plastic recycling within industrial applications in order to reduce this significant waste management pressure. The present study used recycled polylactic acid (PLA) material as a feedstock for the 3D printing of a centrifugal semi-open pump impeller. The technical performance of 3D printed recycled PLA material and virgin PLA material was compared in this study. The environmental impacts for technically feasible impellers were assessed through the environmental life cycle assessment, while costs were evaluated by life cycle costing. The results were incorporated into a techno-eco-efficiency framework to compare the technical properties, environmental impacts, and costs. The social impacts of additive manufacturing and recycled feedstock material were also explored. The technical assessment results indicated that tensile strength, fatigue strength, density, and hardness decreased with recycled material content compared to virgin material. Microscopy of the fracture surfaces revealed the presence of slightly higher porosity and defects in recycled specimens, which could result in slightly lower technical properties. However, the recycled material was accepted for further ecological analysis as it offered higher pumping performance when compared to the original component and could reduce the burden on virgin material-based production and waste material disposal. Importantly, the results showed that 3D printed recycled PLA impellers are more eco-efficient when compared to 3D printed virgin PLA impellers. [ABSTRACT FROM AUTHOR]

In invertebrates inhabiting hydrothermal vent areas, hypotaurine, a precursor of taurine, is thought to mitigate the toxicity of hydrogen sulfide in vent fluids. Information about hypotaurine synthesis pathways in invertebrates is limited, although two pathways, the cysteamine [2-aminoethanethiol (AET)] pathway and the cysteine sulfinate (CSA) pathway are known in mammals. In this study, we cloned a cDNA encoding AET dioxygenase (ADO), the central enzyme of the AET pathway, from the vent mussel Bathymodiolus septemdierum. In the encoded protein (BsADO), functionally important residues, including metal-binding histidines, are conserved. In maximum likelihood phylogenetic analysis, BsADO clustered with ADOs of other invertebrates. By reverse transcription PCR, BsADO mRNA was detected in all tissues examined at similar levels, suggesting that its function is distinct from that of the CSA pathway, predominantly expressed in the gill. BsADO with a His tag, expressed in Escherichia coli in the presence of Fe2+, converted AET to hypotaurine, but BsADO expressed in the absence of iron exhibited lower activity. BsADO was active from pH 8 to 11, and from 0 °C to 37 °C, with a peak at 20 °C. This is the first functional characterization of ADO in marine invertebrates. [ABSTRACT FROM AUTHOR]

The current research aims to design a fuzzy multiobjective model of the reverse logistics supply chain network in the automotive industry, taking into account the energy and time reduction approach. The automobile industry is one of the industries with a high demand worldwide. To continue the competition, the manufacturers of the leading car equipment should strive for better product quality by continuously improving their production processes, directing the production of greenhouse gases with low carbon levels, and increasing sustainability. In this regard, reverse supply chain networks and closed-loop chains have unique features that are very useful in the industry under review. The goal is to transform this model into a supply chain of a secure link in the automotive industry. Deterministic methods, genetic algorithm, particle swarm algorithm, and several scenarios with different aspects have been used to solve the model. The results show that the effectiveness of the three ways in terms of solution time is higher in the deterministic solution method. Proper use of the proposed process can help managers effectively manage the flow of recycled products concerning environmental considerations, and this process provides a sustainable competitive advantage for companies. [ABSTRACT FROM AUTHOR]

Herein, a cradle-to-cradle recycling of post-consumer NMC batteries has been demonstrated with a focused separation of cobalt over nickel by applying the ionic liquid, trihexyl(tetradecyl)phosphonium bis-2,4,4-(trimethylpentyl)phosphinate. At the optimized condition of: 0.8 mol·L−1 ionic liquid, 3.0 mol·L−1 Cl− ions, equilibrium pH value ∼5.0, and organic-to-aqueous ratio 2/3, > 99% cobalt was extracted in the organic phase with a separation factor of 1097. Approximately 99% cobalt from the loaded organic was stripped back in 2.0 mol·L−1 HCl solution, yielding high-pure CoCl 2 · x H 2 O crystals after crystallizing the stripped solution. Subsequently, ∼99% of nickel from the Co-depleted raffinate was extracted over lithium using 0.32 mol·L−1 acetophenone at an organic-to-aqueous ratio of 1 and equilibrium pH ∼5.3. Nickel stripped in 2.0 mol·L−1 H 2 SO 4 was crystallized to yield high-pure NiSO 4 · 6 H 2 O crystals. Further, Li-bearing raffinate was subjected to carbonate precipitation at a higher pH (∼12) and CO 3 2−:Li+ ratio of 1.2. All the recycled products were further employed to the stepwise synthesis of a new ternary precursor, exhibiting similar electrochemical behaviour (with 149 mAh·g−1 capacity) and found compatible with the precursor prepared using virgin materials. The sustainable process index value determined to be 0.0006 cap·t−1 for the overall recycling process indicated that the process is suitable for sustainable development. [Display omitted] [ABSTRACT FROM AUTHOR]

Fiber-reinforced composites, such as carbon and glass fibers, are widely used across various industries. This is mainly a result of their outperforming properties in contrast with traditional materials. As a response to the environmental legal enforcement of the recycling of composite materials, several recycling methods such as mechanical, thermal, and chemical recycling, have been developed. Despite various merits, these recycling methods still face challenges, such as the heterogeneity of material, the quality of the recycled product, the high cost of recycling, and a lack of an established market. Since, in many cases, the financial aspect tends to be the major barrier to recycling composites, the appropriate cost modelling of the recycling process requires urgent consideration. To the knowledge of the authors, there is no prior research efforts on the reviewing of cost modelling techniques on composites recycling. Cost modelling research projects for different recycling technologies, with their findings and limitations, are sought from the literature and reported in this paper. It is found that recycling techniques still cannot compete with traditional landfilling in terms of cost, and are dependent on fiber recovery rates and plant capacities. Following a comprehensive literature review, research gaps are identified to formulate the research directions in this field. [ABSTRACT FROM AUTHOR]

Building sufficient recycled water infrastructure is an effective way to solve problems related to water shortages and environmental degradation, and is of great strategic significance for saving resources, protecting the ecological environment, and promoting sustainable social and economic development. Although recycled water is environmentally friendly, the public is still skeptical about its use, which has led to the failure of a large number of recycled water infrastructure investments; therefore, increasing the public's willingness to re-use is critical for the construction of recycled water infrastructure. To identify the influence mechanism of user comments on public re-use behaviors, we conducted an eye-tracking experiment in China. The results demonstrated that (1) perceived usefulness, perceived quality, and perceived risk have significant impacts on the public's willingness to buy; (2) user reviews can enhance the public's perceived usefulness of recycled products and increase their willingness to buy; and (3) in the process of consumption, the public tends to pay attention to negative reviews, where user reviews alter the perceived risks and perceived prices of recycled products, thereby affecting the willingness to buy of consumers. This study provides a scientific reference for the construction of recycled water infrastructure and the further promotion of recycled water. [ABSTRACT FROM AUTHOR]

The new Law 7/2022, on Waste and Contaminated Soils, introduces important changes in terms of textile waste, a sector that has traditionally received less attention in terms of the volume and management of waste produced. The textile industry is, in fact, the fourth most polluting in terms of waste volume and, in addition, it has been increased by the social practice of fast fashion employment. Due to the aforementioned, the European Directive ((EU) 2018/851) which modifies Directive 2008/98/EC on waste is of particular importance. This new Directive obliges the Member States to the selective collection of textile waste before January 1st, 2025, and to establish objectives related to the preparation for reuse and recycling of this waste. This will have an impact on the entire textile value chain as it will be necessary for companies to start designing and preparing their products to contain recycled material and to allow its recycling. The new tendencies in the management of textile disposables promote an increase in public awareness about consumption practices as well as the co-responsibility of producers and users. The management of textile waste, whose main destination is the social economy, will have to promote technologies for the recovery of surpluses to reintroduce these materials into the consumption process, thus favoring the circular economy and sustainability. [ABSTRACT FROM AUTHOR]

High performances of thermosets deriving from their covalent intermolecular cross-link bonds result in their low recyclability hindering the full exploitation of a truly circular approach for cured thermosets. In this experimental work, the recyclability of a bio-based fully recyclable epoxy resin using a mild chemical recycling process was demonstrated. The recycled polymer obtained was fully characterized to ascertain its structure and properties. MALDI (Matrix-Assisted Laser Desorption/Ionization), GPC (Gel Permeation Chromatography) and NMR (Nuclear Magnetic Resonance) spectroscopy to determine the chemical structure of the recycled polymer were used. The thermomechanical properties of the cured virgin network and of the recycled product obtained were measured by DSC (Differential Scanning Calorimetry) and DMA (Dynamic Mechanical Analysis). Thermogravimetric analysis of the recycled polymer was also performed. The recycled polymer was transformed into a polyurethane by reacting it with an isocyanate. The synthetized polyurethane obtained therefrom was thoroughly characterized by thermogravimetric analysis. This approach proved the possibility to up-scale the recycled product making it available for novel applications exploiting its re-use. [ABSTRACT FROM AUTHOR]

As human activities are increasingly exploiting our planet's scarce resources, managing them has become of primary importance. Specifically, this study examines the management of photovoltaic (PV) waste that is produced when PV modules reach end-of-life (EoL). PV modules contain precious and valuable materials, as well as toxic materials that may be harmful to human health and the environment if not disposed of properly. First, this study aims to review and analyze the current literature in order to gain a deeper understanding of the recycling of PV modules, particularly c-Si modules, which represent the largest market share. In the second part, an analysis is conducted of the energy consumption of these recycling processes using a proposed model based on the full recovery end-of-life photovoltaic (FRELP) process. PV modules manufactured from raw materials and PV modules manufactured from recycled materials are also compared in this section. In addition, improvements are suggested with respect to the design of PV modules (eco-design). According to this study, c-Si PV modules can be recycled with an energy consumption as low as 130 ÷ 300 kWh/ton of treated PV waste, estimating an overall recycling yield of about 84%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using a pressure washing system shortens the length of time for delamination. • Fractional factorial design is used to screen factors. • Particle size, morphology, and acid leaching of products are evaluated. Recycling cathode materials from spent lithium-ion batteries has the potential to reduce damages to the environment and human health due to hazardous waste treatment, and mitigate supply risks of raw materials. Related political incentives or regulations have led to increased research and development efforts on cathode recycling. Promising approaches include direct recycling and hydrometallurgical processes, where delamination is the first step after collection of cathodes. In this study, we examined a pressure washing system's ability to harvest cathode materials. A high-pressure water jet provides strong forces to overcome the adhesion provided by organic binders. Four factors (water pressure, distance between nozzle and cathode, incident angle of water jet, and nozzle type) were investigated using a 34-1 fractional factorial design to screen important parameters and find the optimal conditions. Compared with other delamination processes where chemical reagents and heating are involved, the chemical-free pressure washing system can achieve separation in a few seconds (∼74 min/m2) at room temperature, which remarkably improves the efficiency of delamination. The particle size of recycled products (D50 of 31.87 μ m) is significantly reduced without Al contamination from current collectors or morphological damages. In addition, three types of recycled cathode materials were used as inputs for the acid leaching process. High leaching efficiencies of lithium (>90 %) and cobalt (>85 %) suggest that the pressure washing system could be a practical, economical, and eco-friendly pretreatment process to harvest cathode materials. [ABSTRACT FROM AUTHOR]

Environmental protection is a global objective and a key factor in future development. Decreasing volatile organic compounds and replacing fossil-based materials are considered huge challenges in the ecofriendly polyurethane (PU) industry. Although replacing solvent-based PU by water-based polyurethane dispersions (PUDs) is crucial, PUDs still contain some organic solvents, which should be removed by vacuum evaporation. In addition, the use of biobased materials derived from renewable sources instead of fossil-based materials is considered an ecofriendly technique. In this study, we synthesized biobased PUDs with a biomass polyether diol (polypropanediol H1000) through a patented solvent-free process without the addition of any organic solvent. We synthesized a series of solvent-free biobased PUDs by using H1000 incorporated with fossil polyether diol (poly(tetramethylene ether) glycol T1000) with various biocontents of formulation (60, 50, 40, 30, and 0 wt.%). When using biobased 60 wt.% PUD, Bio60-H100, the adhesion force is higher than fossil materials source, Bio0-H0 by cross-cut and scrub test. This is because of the high ether group concentration and increased number of intermolecular hydrogen bonds in H1000. As indicated by stress–strain curves, the toughness of the PU films from hard to soft when the ether group concentration of PU soft segments increased. In addition, the solvent-free biobased PUDs were flexible, exhibited superior softness, and demonstrated increased tear strength on recycled polyester fabric with a fluoride-free water-repellent agent (C0 W/R). In summary, we developed a series of high-biocontent environment-friendly solvent-free PUDs with favorable storage stability, which can be used in textile coating in the sustainable fabric industry. [ABSTRACT FROM AUTHOR]

The present work reports the use of recycled carbon fibers (rCF), obtained from pyro‐gasification treatment of carbon fibers reinforced polymers (CFRP), to produce a thermoplastic composite filament for additive manufacturing, in particular fused deposition modeling (FDM) process. Polylactic acid (PLA), a thermoplastic biobased and biodegradable polymer, is used as matrix for the composite filament, as it is the most common plastic used in FDM due to its good mechanical properties, stiffness, and strength. Upon production process optimization, filaments with rCF loadings of 5 and 10% wt are produced and analyzed. A particular attention is devoted to the evaluation of the production process on the carbon fibers (CFs) length and the study of the thermal and mechanical properties of the obtained composite materials. [ABSTRACT FROM AUTHOR]

The present work studies the use of olive pit (OP) as a reinforcement in the manufacture of composites based on a post-consumer recycled polypropylene (rPP). In this way, it is feasible to provide added value from olive pits, a by-product resulting from the olive industry operations, while promoting the circular economy and reducing the use of fossil-based polymers. For this purpose, suitable samples were manufactured using 25 wt% and 40 wt% of OP. Additionally, the effect of incorporating additives was studied: (a) a process control additive (PA), and (b) a coupling agent of maleic anhydride grafted polypropylene (MAPP). The results showed an improvement in Young's and flexural modulus with the OP addition. The incorporation of PA did not present any significant improvement in the properties of the materials, nevertheless it facilitated the biocomposite manufacturing process. As for the coupling agent, it significantly improved the mechanical properties, achieving the best results with the addition of the two types of additives and 40 wt% of OP. Moreover, the thermal properties were maintained, and there was an increase in crystallinity in all composites compared to rPP. According to the results of the fracture surface analysis, the coupling agent improves reinforcement-polymer matrix cohesion. [ABSTRACT FROM AUTHOR]

The footwear processes generate a large amount of waste on the soles' cutting and finishing steps. Styrene–butadiene rubber (SBR) is commonly used as feedstock for soles, mainly presenting good abrasion resistance, deformation and durability. These features make SBR a candidate for the manufacturing of non-slip surfaces, that provide softness, low density and wear resistance. The objective of this work was to develop a polymeric matrix composite material, using SBR scraps, from the shoes' production, to design the non-slip surfboard decks. Composites, composed by different ratios of SBR (i.e., 20, 40, and 60 wt.%) and polymer matrices (i.e., polyvinylchloride (PVC), ethyl vinyl acetate (EVA), and styrene–butadiene styrene (SBS) rubber) were developed and characterized by tensile, morphological and apparent density. The main results showed that the SBS/SBR composite closely met the adhesion requirements for the final application, containing 20 wt.% SBR scraps. [ABSTRACT FROM AUTHOR]

Excess waste tires in Puerto Rico pose health and fire hazards. A policy was proposed to switch 75% of paving materials to asphalt modified with recycled ground tire rubber (GTR). Recycling would mitigate the health risks and fire hazards while reducing the dependence on the export of waste tires for energy recovery. This study uses a lifecycle assessment (LCA) and two scopes to inform the policy from an environmental perspective. The pavement-level analysis compares the conventional and rubberized pavement pilot sections. The system-level analysis evaluates the consequences of the policy's tire diversion from tire-derived fuel (TDF) to GTR. In doing so, this study bridges the gap between the waste management LCAs (focused on processing and less on the use of recycled products) and pavement LCAs (which assess GTR in pavements but not potential waste stream reductions). The results of the pavement-level analysis indicated that GTR pavements present higher impacts than their conventional counterparts. The increased impacts of the GTR section are primarily due to the higher binder content, increased mixing energy, and the binder modification process. The system-level analysis revealed that paving in Puerto Rico can use 6–16% of annual waste tires. When TDF replaces environmentally intense kiln fuels (coal and petroleum coke), tire diversion into GTR is not environmentally beneficial. Conversely, when replaced fuels are more environmentally friendly (coal and natural gas), tire diversion to GTR may present benefits. With the use of greener fuels in the cement industry, GTR deployment may gain interest. [ABSTRACT FROM AUTHOR]

Waste poly(vinyl chloride) fill material from the cooling tower of a power plant was used for mechanical recycling. Mechanical recycling is the processing of plastic waste without changing the original chemical structure of the plastic. The waste rigid poly(vinyl chloride) fill material was cleaned, grinded and compression molded at optimized conditions of time, temperature and pressure using a compression molding machine. Virgin poly(vinyl chloride) was purchased and compression molded by the same compression molding machine. The compression molded sheets of waste poly(vinyl chloride) and virgin poly(vinyl chloride) were characterized by attenuated total reflection Fourier transform infrared analyses, tensile properties analyses, and thermal properties analyses. The results revealed that waste rigid poly(vinyl chloride) fill material is mechanically recyclable into new products such as pipes, profiles, furniture and other related products. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing (AM) processes, viz laser powder bed fusion (L-PBF), are becoming an increasingly popular manufacturing tool for a range of industries. The powder material used in L-PBF is costly, and it is rare for a single batch of powder to be used in a single L-PBF build. The un-melted powder material can be sieved and recycled for further builds, significantly increasing its utilisation. Previous studies conducted by the authors have tracked the effect of both powder recycling and powder rejuvenation processes on the powder characteristics and L-PBF part properties. This paper investigates the use of multiple linear regression to build empirical models to predict the part density and surface roughness of 316L stainless steel parts manufactured using recycled and rejuvenated powder based on the powder characteristics. The developed models built on the understanding of the effect of powder characteristics on the part properties. The developed models were found to be capable of predicting the part density and surface roughness to within ±0.02% and ±0.5 Ra, respectively. The models developed enable L-PBF operators to input powder characteristics and predict the expected part density and surface roughness. [ABSTRACT FROM AUTHOR]

Fast pyrolysis of biomass in a fluidized bed reactor is typically conducted in a nitrogen gas environment. Recycling product gas can improve the economics of operating such a system by reducing reliance on pure process streams, but much less is known about how recycling pyrolysis product gas may affect fluidization behavior and pyrolysis kinetics. Therefore, gas effects in a fluidized bed biomass pyrolysis reactor were investigated using engineering correlations, low-order models, and CFD simulations for N 2 , H 2 , CO, CO 2 , and CH 4 carrier gas mixtures. Our findings reveal viscosity of a gas mixture can be significantly underestimated depending on the model and correlation. Furthermore, fluidization characteristics such as U mf and gas-solid convective heat transfer can be greatly affected by the gas properties. By utilizing H 2 as the fluidizing gas (instead of N 2), while maintaining a constant fluidization ratio (U s /U mf), the bio-oil yields can be increased ∼5%. This is due to the lower density H 2 producing similar hydrodynamics as N 2 at higher gas flow rates. These higher flow rates result in shorter gas residence times, and as a result, less secondary reactions that convert bio-oil to light gases and char. Model results also suggest that bio-oil yield is not significantly affected by the type of carrier gas used, with bio-oil yield varying by ∼2% across different gas mixtures while maintaining constant flow rate. This indicates that recycled pyrolytic gas can be used as the carrier gas for biomass pyrolysis. • Correlations for gas mixture properties do not provide consistent results. • Secondary reaction kinetics for pyrolysis do not account for gas phase properties. • Bio-oil yields can increase 5% with low molecular weight fluidization gases. [ABSTRACT FROM AUTHOR]

This investigation assesses the embodied energy and carbon footprint in the manufacture of pavers using varying proportions of recycled Construction and Demolition Waste (CDW). Additionally, Thin Film Composite Polyamide fiber (TFC PA), extracted from end-of-life Reverse Osmosis (RO) membranes, is introduced as an additive to enhance the concrete's strength. Machine learning techniques, namely Artificial Neural Network (ANN), Support Vector Regression (SVR), and Response Surface Methodology (RSM), are employed to predict the mechanical properties of pavers. The study focuses on examining the energy required and embodied carbon in various mix proportions, as well as the mechanical properties—specifically compressive strength and split tensile strength of concrete with different CDW and TFC PA proportions. Findings reveal that the optimal percentage of TFC PA is 3 % for all CDW replacement proportions, resulting in low carbon content both in terms of energy and embodiment and in mechanical behavior. The implementation of ANN and SVR is conducted in MATLAB, while a Design Expert is employed to generate the experimental design for RSM. The RSM regression model demonstrates a robust correlation between variables and observed outcomes, with optimal p-values, R2 values, and f-values. The ANN model successfully captures the variability in the data. Additionally, the findings indicate a consistent superiority of the Support Vector Regression (SVR) model over both Artificial Neural Network (ANN) and Response Surface Model (RSM) models when considering diverse performance metrics such as residuals and correlation coefficients. • Embodied energy and carbon were assessed for the paver block using CDW and polyamide. • Machine learning tools, namely RSM, ANN, and SVM, are used to predict the properties. • The TFC PA plays a crucial role in enhancing the concrete properties. • The optimal percentages of TFC PA and CDW are 3 % and 100 %, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • H 2 O 2 electrosynthesis optimized in a dual membrane electrode assembly. • Moderate catalyst loading enhances mass transport and accessible active sites. • Hydrophobic treatment reduces surface area but improves electrode stability. • Operating in recycle reduces H 2 O 2 degradation in the solid electrolyte chamber. Hydrogen peroxide (H 2 O 2) synthesis via the electrocatalytic reduction of oxygen is a sustainable alternative to the energy-intensive anthraquinone oxidation process. The use of gas diffusion electrodes in dual membrane electrode assembly (MEA) solid electrolyte (SE) electrolyzers has substantially improved H 2 O 2 production, but the influence of mass transport and local reaction environment on H 2 O 2 performance in these cell architectures is still unclear and unoptimized. Herein, we investigate the impacts of electrode components and reactor operating conditions on the H 2 O 2 performance and cell potential required to reach current densities up to 400 mA cm−2. Results show an intermediate catalyst loading of 2 mg cm−2 improves H 2 O 2 production through balancing O 2 diffusion and active site exposure. Hydrophobic treatment via fluoropolymer improves electrode stability, but addition of >15 wt% fluoropolymer worsens performance, likely by limiting active site accessibility at the catalyst-membrane interface. Moreover, decreasing O 2 concentration from typical pure streams to match the composition of air has a negligible effect at moderate current densities (∼50 mA cm−2), but significantly impacts overall performance at higher current densities (∼200 mA cm−2). This work also highlights benefits of operating the reactor with a recycled product stream rather than tuning the flow rate of water over the SE to extremely low values to obtain high H 2 O 2 concentrations, as the latter likely contributes to exacerbated H 2 O 2 degradation in the electrolyzer. This work provides insights into how macroscale system properties in flow cell electrolyzers impact the local reaction environment and mass transport, which in turn dictate overall catalytic performance. [ABSTRACT FROM AUTHOR]