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The exponential growth in plastic production and usage has escalated global concerns about plastic pollution, particularly regarding harmful chemical additives. Understanding the anthropogenic cycles of these additives is the prerequisite to developing effective strategies for plastic pollution control and a toxics-free circular economy. Here we analyze 269 anthropogenic cycles of plastic additives by reviewing 42 extant academic articles to identify research gaps and needs. Based on their characteristics and the available knowledge, we classify these plastic additives into five research priority levels, with 3,116 designated as "urgent level", further subgrouped into 17, 14, and 20 additive categories considering their functions, polymer types, and application sectors, respectively, to inform future investigations. Four key research gaps are highlighted: limited research coverage for hazardous chemical additives, lack of specificity to plastic products, incomplete consideration of life cycle stages and relevant flows, and insufficient attention to policy implications. To close these gaps, we recommend expanding the scope of plastic additives with a specific focus on urgent-level cases, exploring all chemical flows tailored to various plastic types, enhancing the quality and accessibility of relevant data, and fostering a mechanism for strong science-policy-society interactions on the management of plastic additives. This review offers a roadmap for advancing research on material flow analysis of plastic additives and sustainable plastic management. [ABSTRACT FROM AUTHOR]

Dislocation evolution in multilayered Ti/Nb composites processed by accumulative roll bonding under uniaxial tension was quantitatively evaluated by high-energy X-ray diffraction. The composites with different heterogeneous microstructures show distinct dislocation activities in Ti, which majorly contributes to their different ductility. For the composite in which extensive shear bands have formed before loading, the stable fraction of 〈c+a〉 dislocations and the suppressed activation of 〈c〉 dislocations contribute to its uniform deformation. We emphasize that tracking the dynamic evolution of dislocations is fundamental for understanding ductility of the multilayers, whereas the increased 〈c+a〉 dislocations found by post-mortem analysis do not necessarily dominate. IMPACT STATEMENT: Dynamic evolution of dislocations, rather than only dislocation densities obtained by post-mortem analysis, is found to explain ductility of multilayered composites, which can be tailored by adjusting heterogeneous microstructures. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of the ultimate strength of a light-rail hybrid cable-stayed bridge (CSB) and discusses the influences of the concrete tension softening effect (CTSE), which is defined as the tensile strength of concrete being much less than its compressive strength. Both geometrical and material non-linearities are considered. A finite-element model of the bridge was established using Ansys software, with material non-linearity considered through the fibre beam element Beam189. An algorithm was written using Fortran language for the uniaxial concrete constitutive model to consider the CTSE (i.e. the concrete smeared crack model). The results showed that the CTSE significantly influenced the ultimate strength of the investigated bridge when the side-span concrete girder dominates the failure of the bridge as estimated by calculations. It is essential to consider the CTSE for the evaluation of the ultimate strength of a light-rail hybrid CSB. [ABSTRACT FROM AUTHOR]

Sandstones exhibit a complex, stress-dependent behavior characterized by nonlinearity and inelasticity. This study delves into the mechanical properties of sandstone through two distinct triaxial compression experiments: monotonic and cyclic tests, under confining pressures ranging from 0 to 20 MPa. Based on plastic strain analysis, two stress-dilatancy models were developed to describe nonlinear plastic dilatation behaviors. The introduction of the "plastic dilatancy line" concept, derived from comparing plastic dilatancy stresses with crack damage strengths, marks a significant advancement in understanding sandstone's inelastic models. It was found that the plastic flow directions are not perpendicular to the yield surfaces marked by the characteristic strengths. This indicated that the non-associated flow rule is suitable to describe the macroscopic plastic deformations of sandstone. Furthermore, it was identified confining pressure as the dominant influence on sandstone failure, with cyclic loading modes playing a secondary role. An increase in confining pressure shifts the macroscopic failure modes from splitting-tension to mixed shear-tension, and ultimately to shear failure. Scanning Electron Microscope (SEM) analyses indicated that loading–unloading (L–U) cycles induce more significant mineral grain fragmentation compared to monotonic testing, thereby markedly decreasing sandstone's failure strength due to accumulated damage from grain-crushing. Additionally, the dip angles of dominant fractures in samples subjected to cyclic tests are typically smaller than that in monotonic tests. This investigation not only sheds light on the complex mechanical behaviors of sandstones but also provides a vital theoretical and practical framework for future research in this field. [ABSTRACT FROM AUTHOR]

The future of diesel engines is greatly influenced by ongoing research on alternative fuels. Renewable fuels have been researched and adopted by several nations to encourage the production and use of biodiesel. This study examines the energy conversion of waste plastic biodiesel and Spirulina microalgae biodiesel at a 20% blending ratio to analyze the behavior of a one-cylinder, 4-stroke diesel engine running at 1500 rpm with a compression ratio of 17.5. The authors evaluated, analyzed, and compared the engine's combustion, performance, and emission at an incremental engine load of 25% from 25 to 100%. The findings demonstrated that the biodiesel fuel samples generated somewhat poorer efficiency but reduced emissions from the engine. At 100% load, the percentage differences between the diesel and blended fuel samples ranged from 2.4 to 7.3% for BTE, 2.9 to 16.5% for BSFC, and 1.0 to 4.62% for BSEC; however, the PM, SO2, and CO2 emissions were reduced by 1.6–28.8% except for NOx emissions, which are increased by up to 9.4%. Pure diesel exhibits the best performance characteristics; however, pure biodiesel exhibits the best emission characteristics. The 20% blended fuels showed promising results, as they exhibited comparable or slightly improved BTE values compared to their respective pure biodiesel fuels. The findings indicate that Spirulina microalgae biodiesel and waste plastic biodiesel have the potential to be utilized as substitute fuels for diesel engines; however, for the greatest performance and lowest emissions, their blending ratios and engine operating conditions must be optimized. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear elasto-plastic analysis method under incremental external loads is presented to determine static pushover curves of 3D frame structures. Geometric nonlinearity is taken into account with stability functions, and the nonlinear behaviour of material is considered by plastic hinge hypothesis. Improved matrices and matrix operations for 3D frame elements are given, and the results obtained from a six-storey 3D frame, which is used as a benchmark example, are given comparatively with the related studies. Furthermore, in order to perform these analyses with the developed algorithms, the upgraded computer program TUNAL is used to present pushover curves of a 2-storey RC building for an assumption on torsional stiffness caused by plastic hinges. It is shown that the proposed methodology and the computer program give accurate and reliable results. [ABSTRACT FROM AUTHOR]

Plastics are widespread pollutants found in atmospheric, terrestrial and aquatic ecosystems due to their extensive usage and environmental persistence. Plastic additives, that are intentionally added to achieve specific functionality in plastics, leach into the environment upon plastic degradation and pose considerable risk to ecological and human health. Limited knowledge concerning the presence of plastic additives throughout plastic life cycle has hindered their effective regulation, thereby posing risks to product safety. In this study, we leveraged the adverse outcome pathway (AOP) framework to understand the mechanisms underlying plastic additives-induced toxicities. We first identified an exhaustive list of 6470 plastic additives from chemicals documented in plastics. Next, we leveraged heterogenous toxicogenomics and biological endpoints data from five exposome-relevant resources, and identified associations between 1287 plastic additives and 322 complete and high quality AOPs within AOP–Wiki. Based on these plastic additive–AOP associations, we constructed a stressor-centric AOP network, wherein the stressors are categorized into ten priority use sectors and AOPs are linked to 27 disease categories. We visualized the plastic additives–AOP network for each of the 1287 plastic additives and made them available in a dedicated website: https://cb.imsc.res.in/saopadditives/. Finally, we showed the utility of the constructed plastic additives–AOP network by identifying highly relevant AOPs associated with benzo[a]pyrene (B[a]P), bisphenol A (BPA), and bis(2-ethylhexyl) phthalate (DEHP) and thereafter, explored the associated toxicity pathways in humans and aquatic species. Overall, the constructed plastic additives–AOP network will assist regulatory risk assessment of plastic additives, thereby contributing towards a toxic-free circular economy for plastics. [ABSTRACT FROM AUTHOR]

This paper presents micromechanical analyses of an orthogonally reinforced composite with new constitutive equations of kinematic plastic hardening. The homogenization of plastic properties was performed through a numerical analysis of a representative volume using the finite element method. A modification of Prager's theory was used to construct physical relations for an equivalent orthotropic material. In the proposed version of the theory, a special tensor for back stresses is introduced, which takes into account the difference in the rate of hardening for different types of plastic deformation. For boron–aluminum orthogonally reinforced composite with known mechanical properties of fibers and matrix, all material parameters of the theory were determined, deformation diagrams were constructed, and the equation for a plasticity surface in a six-dimensional stress space was obtained. The advantage of the developed method of numerical homogenization is that it only requires a minimal amount of experimental data. The efficiency of micromechanical analysis makes it possible to optimally design metal matrix composites with the required plastic properties. [ABSTRACT FROM AUTHOR]

The aim of this study is to provide a solution for the plastic limit pressure and stress intensity factor of the elbows containing a part-through axial semi-elliptical crack by considering various crack sizes. The supporting system and loading conditions of the pipeline are described. The critical part of the observed pipeline was isolated for analysis and subjected to various sizes of semi-elliptical cracks. By performing numerical analysis, results were obtained for crack dimension ratios of c/a, and depth/thickness ratios of a/t. The obtained results include plastic limit pressure and stress intensity factor. The results were analyzed with a symbolic regression algorithm, and closed-form solutions for the limit pressure and stress intensity factor were proposed. To validate pipeline integrity, the Structural Integrity Assessment Procedure (SINTAP) was applied, and the FAD (Failure Assessment Diagram) was generated for cracks below the FAD function. The failure pressure was calculated by determining the points where the loading paths intersect the FAD function. [ABSTRACT FROM AUTHOR]

Microplastic analysis is a crucial step for locating the environmental contamination sources and controlling plastic contamination. A popular tool like Fourier transform infrared (FTIR) spectroscopy is capable of identifying plastic types and can be carried out through a variety of containers. Unfortunately, sample collection from water sources like rivers usually involves filtration so the measurements inevitably include the membrane filter that also has its own FTIR characteristic bands. Furthermore, when plastic particles are small, the membrane filter's spectrum may overwhelm the desired plastics' spectrum. In this study, we proposed a novel preprocessing method based on the dictionary learning technique for decomposing the variations within the acquired FTIR spectra and capturing the membrane filter's characteristic bands for the effective removal of these unwanted signals. We break down the plastic analysis task into two subtasks — membrane filter removal and plastic classification — to increase the explainability of the method. In the experiments, our method demonstrates a 1.5-fold improvement compared with baseline, and yields comparable results compared to other state-of-the-art methods such as UNet when applied to noisy spectra with low signal-to-noise ratio (SNR), but offers explainability, a crucial quality that is missing in other state-of-the-art methods. The limitations of the method are studied by testing against generated spectra with different levels of noise, with SNR ranging from 0 to – 30dB, as well as samples collected from the lab. The components/atoms learned from the dictionary learning technique are also scrutinized to describe the explainability and demonstrate the effectiveness of our proposed method in practical applications. [ABSTRACT FROM AUTHOR]

Self-excited oscillating cavitation waterjet (SOCW) has good prospects for application in concrete-breaking in the ocean. This study investigates the breaking mechanism of concrete subjected to SOCW in a submerged environment, with a focus on identifying damage characteristics at both macroscopic and microscopic levels using scanning electron microscopy and computed tomography. The breaking effect of concrete under the impact of SOCW at various impact times, jet pressures, impact distances, and strength grades was compared. It was found that (a) the best breaking effect of concrete was achieved by ensuring a 30 MPa jet pressure with a 5 mm impact distance. (b) Internal pores of concrete and the water wedge effect accelerated crack propagation. The formation of breaking pits was the result of closed loops formed by cracks leading to concrete spalling. (c) Microscopic analysis revealed plastic deformation pits on the concrete surface, forming through stages of cavitation collapse, pore expansion, and coalescence. This study provides a theoretical understanding and technical support for follow-up research on the parameter optimization and breaking efficiency of concrete-breaking technology. [ABSTRACT FROM AUTHOR]

The upsurge in the usage of plastics on a global scale has led to the widespread occurrence of microplastics (MPs) in aquatic environments. This review starts by outlining the current global scenario of plastic production. It then delves into the various sources of plastics and their entry into aquatic systems, including their impact on fisheries and the aquaculture sector. The detailed analysis of plastic entry and various methods of degradation into small sized, MPs followed by their transport, uptake and trophic transference have been reviewed systematically. Besides, the review summarizes the current knowledge on impacts of MPs, their additives and associated contaminants on organisms living in the aquatic environment, particularly fish thriving in cultured conditions. The analysis of effects of MPs alone and in association with other contaminants like heavy metals, organic pollutants and leachates reveal serious effects such as cytotoxicity, immune response, oxidative stress, neurotoxicity, barrier attributes and genotoxicity among various aquatic species particularly, fish. In addition, the present review discusses MPs invasion into aquaculture systems, explores risk assessment both in terms of exposure risk and toxicological risks associated with biochemical nature, size, shape and concentration of MPs. Besides, risk management strategies and future prospective to control MPs associated hazards have also been highlighted. In summary, the present review outlines the various sources, fate, impact of MPs in aquatic environment highlighting the need to recognize MPs pollution as a serious threat to aquatic organisms and to formulate strategies including prevention, reduce, reuse and safe disposal of plastic material. [ABSTRACT FROM AUTHOR]

The aim of the research was to determine the possibility of producing and using layered composites made of aluminium and magnesium alloys Al1050-AZ31-Al1050. The use of layered composites often results from economic conditions. The work analyzed the current research, technological and production potential, as well as selected microstructural phenomena occurring in the tested multilayer materials and the effects of the rolling process. The material for the study was obtained using the explosion welding technology, one of the few enabling universal joining of often difficult-to-weld metals. The rolling process was carried out on a semi-industrial duo rolling mill with a roller diameter of Ø300 mm. The composite input material for the rolling process was heated to a temperature of 380 °C. The effect of the rolling process on the distribution of metal pressure forces on the rolls, the geometric parameters and the microstructural changes occurring in the plastically formed layered composite were an-alysed, and the energy gain from using a structure in which the currently used aluminium com-ponents were replaced with the tested composite was estimated. The research results presented in this paper prove that in the rolling process of the layered composite there are differences in the deformation values of the Al1050 and AZ31 layers. These differences are caused by the properties of the materials combined into the layered composite. The use of the proposed composite material in industrial conditions will enable the weight of selected elements to be reduced by up to 60%, which will have a positive impact on the energy efficiency of the entire structure. [ABSTRACT FROM AUTHOR]

Hotels are under increasing pressure to reduce their plastic consumption and keep holiday destinations cleaner. Tourism experts already pointed to a variety of solutions, from replacing, avoiding to waste collection campaigns with guests. This study mirrors these measures with the opinions of German consumers who, in the European Union, travel most and mainly for beach holiday. A survey (n = 630) showed that plastic prevention should be practised by holiday organisers, actively involving guests, e.g. in beach clean-ups, was least popular. Personal attitudes towards plastic avoidance had no effect, but rather women and older people were more willing to engage on holiday (max. r = 0.17). Also, agreement tended to decrease with the distance of the holiday destination (max. r = 0.11). For effective marketing, providers of plastic-free holidays should rather avoid this material than replacing it and participate in environmental protection projects on destinations and get certified for this. This most convinces diverse consumer groups, instead of demonstrating sustainability with obligations and bans. [ABSTRACT FROM AUTHOR]

To predict the failure of mechanical parts, it is necessary to understand the residual stress and its source, i.e., inherent strain. In this study, the distribution of three-directional residual stress components in a carburized 18NiCrMo14-6 cylindrical roller test piece with a diameter of 80mm and length of 240 mm, was measured using the extended contour method (XCM), which combines the contour method and X-ray diffraction. Thereafter, an inverse analysis was applied to the measured residual stress to reproduce the associated inherent strain distribution. First, it was shown through numerical experiments of a carburized cylindrical specimen that the distribution of the three-directional residual stress components can be accurately reproduced using XCM. Next, it was demonstrated that the distribution of the three-directional residual stress components could be obtained using general-purpose equipment by physically measuring the same type of specimen. The inherent strain distributions were evaluated. Compressive residual stress and corresponding tensile inherent strain were detected in the carburized layer. By contrast, tensile stress and inherent contraction strain were determined in the non-carburized layer just before the carburized crust. Finally, the mechanism of inherent strain generation was investigated using a thermal--elastic--plastic analysis. Possible explanations include (i) increase in transformation strain due to a change in carbon content, (ii) delay in martensitic transformation, and (iii) decrease in the martensitic transformation rate due to a decrease in the cooling rate at the core. [ABSTRACT FROM AUTHOR]

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research employs plastic limit analysis to examine load combinations, contact interactions, and friction effects on steel–concrete connections. A nonlinear finite element model was developed using ABAQUS 2021, incorporating the concrete damage plasticity model and contact friction interactions. The model's validity was confirmed through laboratory experiments. Results indicate that contact elements and friction between the top flange, concrete slab, and studs significantly influence structural behavior. Unlike conventional push-out tests, real deck–slab connections exhibit different load-displacement responses due to the self-weight and additional loads, such as vehicular traffic. Under horizontal loading, extensive failures with large deformations along the studs occur, while vertically compressive loads lead to failures around the connections. [ABSTRACT FROM AUTHOR]

Plastic products are now essential commodities, yet their widespread disposal leads to environmental and human health effects, particularly in developing nations. Therefore, developing nations require comprehensive studies to assess the current state of plastic and plastic waste production to enhance plastic waste management practices. This review analyzes the import and export of plastic and the production of plastic waste in Rwanda, aiming to improve waste management practices. This review used open-access papers, reports, and websites dealing with plastic waste management. In this review, 58 articles from the Web of Science and 86 from other search engines were consulted to write this review. The findings revealed that the daily estimated plastic waste produced per person ranges between 0.012 and 0.056 kg. The estimated amount of plastic waste generated per person per year in Rwanda could be between 4.38 and 20.44 kg. Plastic waste accounts for between 1 and 8% of the total municipal solid waste produced per person per day in the country, which ranges from 219 to 255.5 kg. The average annual amount of imported plastics could reach 568.2881 tons, whereas the average quantity of exported plastics could reach 103.7414 tons. This shows that plastic management practices have not yet adopted technically advanced or improved practices, which should concern efforts to protect our environment. This study suggests approaches that can vastly improve plastic waste management and potentially open massive opportunities for the people of Rwanda. [ABSTRACT FROM AUTHOR]

Multilayered plastics are widely used in food packaging and other commercial applications due to their tailored functional properties. By layering different polymers, the multilayered composite material can have enhanced mechanical, thermal, and barrier properties compared to a single plastic. However, there is a significant need to recycle these multilayer plastics, but their complex structure offers significant challenges to their successful recycling. Ultimately, the use and recycling of these complex materials requires the ability to characterize the composition and purity as a means of quality control for both production and recycling processes. New advances and availability of low‐field benchtop 1H NMR spectrometers have led to increasing interest in its use for characterization of multicomponent polymers and polymer mixtures. Here, we demonstrate the capability of low‐field benchtop 1H NMR spectroscopy for characterization of three common polymers associated with multilayered packaging systems (low‐density polyethylene [LDPE], ethylene vinyl alcohol [EVOH], and Nylon) as well as their blends. Calibration curves are obtained for determining the unknown composition of EVOH and Nylon in multilayered packaging plastics using both the EVOH hydroxyl peak area and an observed peak shift, both yielding results in good agreement with the prepared sample compositions. Additionally, comparison of results extracted for the same samples characterized by our benchtop spectrometer and a 500‐MHz spectrometer found results to be consistent and within 2 wt% on average. Overall, low‐field benchtop 1H NMR spectroscopy is a reliable and accessible tool for characterization of these polymer systems. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plates and curved plates are essential components in ship construction. In the design stage, the methods used to evaluate the ultimate strength required to confirm the structural safety of plates include prediction through analytical methods, finite-element analysis (FEA), and empirical formulas. However, with nonlinear buckling, the results of the empirical formula and the FEA differ for small flank angles (1~9). As a result, the prediction of the nonlinear ultimate strength of flank angle (1~9) plates still requires significant computation time and cost. To compensate for this, this study performed an ultimate strength prediction method utilizing a deep neural network together with the 4050 curved plate analysis. In addition, this paper presents the analysis results of the nonlinear finite-element method and the geometric shape and ratio of curved plates as training data. Based on the results of this study, designers can more efficiently design appropriate curved plate members by considering the ultimate strength. [ABSTRACT FROM AUTHOR]

In recent years, the development of a circular economy of plastic products in the automotive industry has been pursued by original equipment manufacturers (OEMs) not only due to strategic premises by the European Commission but also due to an increasing demand by customers. To achieve a circular economy, high-quality recyclates are needed. However, in the current situation, there is a discrepancy between the low-quality recyclate that is available on the market and the high-quality recyclate that is demanded by manufacturers. To increase the quality of recyclate on the market, a standardized process to reward a 'design-for-recycling' approach at the product development stage is needed. This paper proposes an allocation method that takes into account material compositions and common recycling processes and incentivizes the preservation of high-quality grades of recyclate based on grade purity. [ABSTRACT FROM AUTHOR]

Warp-knitted spacer fabrics (WKSF), with their unique structure and excellent energy absorption properties, are widely utilized in the automotive industry, medical field, and aerospace sectors. However, during practical applications, WKSF undergo repeated compression, which can lead to compressive fatigue of the spacer yarns and consequently cause the WKSF to undergo irreversible deformation, which subsequently affects its performance and appearance. Therefore, to enhance the compressive properties of WKSF and investigate the mechanisms of plastic failure, this study used a warp knitting double needle bar raschel machine to fabricate a WKSF with a thickness of 20 mm. Through fabric structure analysis, we developed a unit cell model consisting of 32 fibers and a more comprehensive analysis model with 320 fibers to quantitatively assess the geometric changes of the WKSF during the compression process. Furthermore, we experimentally studied the performance changes of the WKSF under different compression speeds, various compression strains, and 1000 cycles of loading. By integrating experimental test with the finite element method, we have conducted an in-depth study of the compression process of WKSF, simulating the displacement U, Von Mises stress distribution, and plastic compression failure behavior during compression. By comparing data on Von Mises stress, equivalent plastic strain (PEEQ), and energy density distribution (SENER), we can clearly observe the performance of spacer yarns under compression conditions, providing significant insights into the underlying plastic failure mechanisms of WKSF's. This study not only enriches the theoretical framework for WKSF compression but also lays a solid foundation for improving its performance and extending its applications. [ABSTRACT FROM AUTHOR]

The advent of three-dimensional stacked chips has significantly enhanced overall performance but introduced challenges in thermal analysis. To ensure the reliable operation of stacked chips and improve the design efficiency of heat sinks, a comprehensive exploration of thermal management issues, the formulation of practical thermal design principles, and the development of a foundational heat transfer analysis model are imperative. In this study, a three-dimensional stacked module is modeled using FloTHERM finite element simulation technology, and its temperature profile is subsequently simulated. The thermal resistance value of the module's shell is calculated to be 37.25 °C W−1. Subsequently, utilizing the instantaneous state dual interface method, the junction-to-case thermal resistance of the module is experimentally measured using T3ster equipment. Two identical modules are tested, revealing a junction-to-case resistance value of 39.45 °C W−1 for module No. 1 and 40.50 °C W−1 for module No. 2—both approximately 40 °C W−1, thereby validating the accuracy and repeatability of the tests. A comparative analysis between the simulated and experimental thermal resistance values indicates an error of approximately − 5.5% for module 1 and − 8.0% for module 2. Further analysis suggests potential sources of error, such as thermal conductivity of the plastic packaging material and hot spot distribution. The paper concludes with simulation-based analyses of plastic packaging material thermal conductivity and hot spot distribution, offering insights for refining the simulation model. This study verifies the correctness of the results obtained by using finite element analysis to build a model for thermal simulation analysis. It has reference value for the thermal simulation analysis and thermal resistance test method of 3D integrated package module. [ABSTRACT FROM AUTHOR]

CLEIN is a mobile application integrated with a specially designed drop box to address the growing issue of plastic bottle waste in the environment. The CLEIN mobile app is empowering communities to act against plastic waste by transforming it into valuable rewards through a points system. To assess usability testing such as effectiveness, efficiency, and user satisfaction of the user experience on the CLEIN mobile app, researchers used the System Usability Scale (SUS) and Time-Based Efficiency Analysis. This approach evaluated the success rate of 22 testers in completing tasks on the CLEIN prototype by calculating their Screen Usability Score (SCUS) using the formula provided by the Maze-App tools. Data collection was carried out through an online questionnaire. The score of 74 falls within the "C" grade range (typically 68-80) on the SUS but is still considered "good" based on the adjective ratings. This suggests that users generally find the app usable, though there might be room for improvement. Users appreciated the app's intuitive and aesthetically pleasing design, along with its user-friendly functionality. To further enhance usability and attractiveness, the CLEIN app can consider several recommendations, such as developing additional features and expanding the types of waste that can be redeemed for points. This research can motivate users to use technology to manage waste. [ABSTRACT FROM AUTHOR]

The rheological properties and stability of cement‐based materials determine the technological properties of concrete mixtures and significantly influence concrete properties. Polycarboxylate ether (PCE) and other plasticizing admixtures are widely used in construction practice to plasticize concrete mixtures. Experimental research on the rheological characteristics of cement mortar modified with PCE and air‐entraining admixtures (AIRs) was carried out with a rotation rheometer with coaxial cylinders and water bleeding tests. Herschel–Buckley or modified Bingham models were used to approximate experimental flow curves and assess rheological parameters such as yield stress, plastic viscosity, and shear thinning/thickening index. The rheological test was carried out at 5 and 90 min after mixing the cement mortar. The rheological test established that the modification of cement mortar by PCE in a dosage of 0.2% (in dry material) leads to a decrease in plastic viscosity of 25.0% with a reduction in water demand of 18% for the same workability. Modification of cement mortar by AIR in 0.3% dosage leads to a decrease in yield stress by 37.7% and a decrease in plastic viscosity by 35.4% compared to the control specimen without PCE. The combined modification by PCE and AIR admixtures shows a synergistic effect. It leads to a significant decrease in yield stress of cement mortar by 92.2% and a decrease in plastic viscosity to about 0 Pa·s. In addition, there is a significant coefficient of water bleeding reduction up to 0%, when additional water reduction was carried out in the mixture while maintaining the same workability. The cement mortar, with or without PCE and AIR, exhibited shear‐thinning characteristics for up to 90 min after mixing. The solid, liquid, and gas (air) phases' influence yield stress and plastic viscosity in the analysis mixtures are presented in this paper. It has been established that a modified exponential Mooney dependency can be used to predict the yield stress and plastic viscosity of the modified cement mortar (both plasticized and air‐entrained). [ABSTRACT FROM AUTHOR]

The quality and readability of online health information are sometimes suboptimal, reducing their usefulness to patients. Manual evaluation of online medical information is time-consuming and error-prone. This study automates content analysis and readability improvement of private-practice plastic surgery webpages using ChatGPT. The first 70 Google search results of "breast implant size factors" and "breast implant size decision" were screened. ChatGPT 3.5 and 4.0 were utilized with two prompts (1: general, 2: specific) to automate content analysis and rewrite webpages with improved readability. ChatGPT content analysis outputs were classified as hallucination (false positive), accurate (true positive or true negative), or omission (false negative) using human-rated scores as a benchmark. Six readability metric scores of original and revised webpage texts were compared. Seventy-five webpages were included. Significant improvements were achieved from baseline in six readability metric scores using a specific-instruction prompt with ChatGPT 3.5 (all P ≤ 0.05). No further improvements in readability scores were achieved with ChatGPT 4.0. Rates of hallucination, accuracy, and omission in ChatGPT content scoring varied widely between decision-making factors. Compared to ChatGPT 3.5, average accuracy rates increased while omission rates decreased with ChatGPT 4.0 content analysis output. ChatGPT offers an innovative approach to enhancing the quality of online medical information and expanding the capabilities of plastic surgery research and practice. Automation of content analysis is limited by ChatGPT 3.5's high omission rates and ChatGPT 4.0's high hallucination rates. Our results also underscore the importance of iterative prompt design to optimize ChatGPT performance in research tasks. [ABSTRACT FROM AUTHOR]

The objective of this study, concerning the soil–structure interaction of shallow reinforced concrete foundations of wind towers with circular cross-sections, was determination in a closed form of the monotonic moment–rotation curve of the soil–foundation complex. This study was based on elastic and plastic analyses of shallow rigid foundations assuming a Winkler soil type including the flexibility of the foundation in the elastic range and the nature of the soil (cohesive and non-cohesive types) through corrective factors of the constant of the Winkler model. The flexibility of the foundations influences the moment–rotation response through the initial rotational stiffness with a coefficient between 1 and 0.7 for a width-to-span ratio between 5 and 2. The nature of the soil is considered through corrective factors of 0.75 and 1.3 of the Winkler constant for cohesive and non-cohesive soil, respectively. Analyses carried out stressed that a possible design valued to be adopted in a steel wind tower with shallow foundations is a diameter of the steel tube 1/15 of the height of the tower, a diameter of foundation 0.75 of the length, and a depth of foundation 1/10 of the diameter and thickness of steel tower ratio diameter equal to 1/10. In this range it was observed that the effects of the soil-to-foundation interaction in the elastic range influences the critical length in the stability of the steel wind tower, with values between 2.5 and 2 (column fixed at the base) in a range of Winkler constant between 0.1 and 1 daN/cm3. Finally, an experimental validation of the proposed model was carried out with the data available from the literature. [ABSTRACT FROM AUTHOR]

An analysis of the processes of plastic deformation and acoustic relaxation in a high-entropy alloy, Al0.5CoCrCuFeNi, was carried out. The following were established: dominant dislocation defects; types of barriers that prevent the movement of dislocations; mechanisms of thermally activated movement of various elements of dislocation lines through barriers at room and low temperatures. Based on modern dislocation theory, quantitative estimates were obtained for the most important characteristics of dislocations and their interaction with barriers. [ABSTRACT FROM AUTHOR]

To fully harness the design development potential of plastic angle sections, this study employs a theoretical analysis approach to examine the plastic behavior of equal angle sections subjected to axial force and biaxial bending. Based on the simplified angle section results, the full plasticity correlation equations were derived. Subsequently, section shape coefficients were computed. Finally, a methodology for calculating the plastic development coefficients of angle sections was explored. The findings indicate that the full plasticity correlation equations lack the necessary safety margins in designs. Notably, the angle sections possess a greater plastic development capacity along the weak axis compared with the strong axis. It is advisable, for both regular-size and large-size angle sections, to consistently adopt the plastic development coefficients in designs as follows: γu = 1.05 for the strong axis and γv = 1.15 for the weak axis, thereby addressing the shortcomings of the specification in design. [ABSTRACT FROM AUTHOR]

Adaptive networks with time-varying connectivity, often called plasticity, provide a fundamental paradigm to model complex dynamical systems. In these systems, different groups of elements frequently exhibit different yet synchronized dynamics within each group. Here we propose a framework to study patterns of synchronous solutions in a large class of plastic networks and derive a general approach to analyze the stability of these solutions. This approach decouples the role of the network topology from that of the dynamic, thus leading to a dimensionality reduction of the stability problem and allowing us to investigate how adaptation affects the emergence of multi-stable patterns of synchronized activity. To illustrate its potentialities, we apply our method to three networks of oscillators, with distinct topology, dynamics, and adaptation rules. Our working framework encompasses a large class of heterogeneous multi-layer dynamical networks, connected (even with delays) via different plastic links, and can have a broad impact on the analysis of complex plastic networks. Complex networks composed of interacting oscillators are frequently characterized by two features: adaptivity and cluster synchronization. Here the authors develop a framework to study the stability of patterns of synchronous solutions in a large class of plastic networks. Three examples illustrate the proposed method. [ABSTRACT FROM AUTHOR]

The cap geometry and formation mechanism play a key role in influencing the hole-making quality on the bore exit side and must be the focus of research in orbital drilling of aeronautical metal materials. For a "bowl shape" cap geometry formed in orbital drilling process, the corresponding undeformed cap periphery geometry, generated by the cap periphery cutting edges, is simulated and given the parametric description. Especially, the cap periphery is simplified as a simply supported annular plate under uniform load with arbitrary loading radius based on the characteristics of the cap periphery shape and mechanical analysis of processing. Then its unified plastic limit analysis is developed. The ultimate load, stress field, and plastic deformation at the periphery of the cap are derived from the unified strength theory. Furthermore, the numerical solutions are obtained in terms of the Tresca yield, Huber–von Mises, and twin-shear yield criteria. The conclusions enabled an in-depth understanding of the cap periphery formation mechanism in the orbital drilling of holes from the unified plastic limit analysis perspective. [ABSTRACT FROM AUTHOR]

Contamination with plastics of small dimensions (<1 µm) represents a health concern for many terrestrial and aquatic organisms. This study examined the use of plastic-binding peptides as a coating probe to detect various types of plastic using a plasmon nano-gold sensor. Plastic-binding peptides were selected for polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS) based on the reported literature. Using nAu with each of these peptides to test the target plastics revealed high signal, at 525/630 nm, suggesting that the target plastic limited HCl-induced nAu aggregation. Testing with other plastics revealed some lack of specificity but the signal was always lower than that of the target plastic. This suggests that these peptides, although reacting mainly with their target plastic, show partial reactivity with the other target plastics. By using a multiple regression model, the relative levels of a given plastic could be corrected by the presence of other plastics. This approach was tested in freshwater mussels caged for 3 months at sites suspected to release plastic materials: in rainfall overflow discharges, downstream a largely populated city, and in a municipal effluent dispersion plume. The data revealed that the digestive glands of the mussels contained higher levels of PP, PE, and PET plastic particles at the rainfall overflow and downstream city sites compared to the treated municipal effluent site. This corroborated earlier findings that wastewater treatment could remove nanoparticles, at least in part. A quick and inexpensive screening test for plastic nanoparticles in biological samples with plasmonic nAu-peptides is proposed. [ABSTRACT FROM AUTHOR]

This article investigated test results of 81 reinforced concrete columns under monotonic flexure load via numerical simulation and experimental studies from the literature to comprehensively discuss the parameters that influence plastic hinge length. Moreover, it proposed a simplified method, based on the compressive strain of longitudinal reinforcing bars, and a new expression to estimate plastic hinge length, based on axial load ratio, shear span‐depth ratio, and longitudinal reinforcement ratio. In addition, it compares and discusses analytical expressions to estimate plastic hinge reported in previous research. The analysis shows that axial load ratio, shear span‐depth ratio, and longitudinal reinforcement ratio strongly influence both lateral load–displacement responses and plastic hinge length. Furthermore, the proposed simplified method is adequate for estimating plastic hinge length. Finally, the results show that the equation proposed as a way of estimating the plastic hinge length provides satisfactory predictions for reinforced concrete columns under monotonic flexure. [ABSTRACT FROM AUTHOR]

Burns and fires in the operating room are a known risk and their prevention has contributed to many additional safety measures. Despite these safeguards, burn injuries contribute significantly to the medical malpractice landscape. The aim of the present study is to analyze malpractice litigation related to burn and fire injuries in plastic and reconstructive surgery, identify mechanisms of injury, and develop strategies for prevention. The Westlaw and LexisNexis databases were queried for jury verdicts and settlements in malpractice lawsuits related to burn and fire injuries that occurred during plastic surgery procedures. The Boolean terms included "burn & injury & plastic", "fire & injury & "plastic surg!"" in Westlaw , and "burn & injury & "plastic surg!"", "fire & injury & "plastic surg!"" in LexisNexis. A total of 46 cases met the inclusion criteria for this study. Overheated surgical instruments and cautery devices were the most common mechanisms for litigation. Plastic surgeons were defendants in 40 (87%) cases. Of the included cases, 43% were ruled in favor of the defendant, while 33% were ruled in favor of the plaintiff. Mishandling of cautery devices 6 (13%), heated surgical instruments 6 (13%), and topical acids 2 (4%) were the most common types of errors encountered. Never events causing burn injury in plastic and reconstructive surgery are ultimately caused by human error or neglect. The misuse of overheated surgical instruments and cauterizing devices should be the focus for improving patient safety and reducing the risk of medical malpractice. Forcing functions and additional safeguards should be considered to minimize the risk of costly litigation and unnecessary severe harm to patients. ● Burn injuries contribute significantly to the medical malpractice landscape. ● Never events causing burns in plastic surgery are caused by human error or neglect. ● Overheated instruments and cauterizers were the leading mechanisms for litigation. ● Additional safeguards should be added to minimize litigation and harm to patients. [ABSTRACT FROM AUTHOR]

Ultrasonic vibration superimposed face milling enables the generation of predefined surface microstructures by an appropriate setting of the process parameters. The geometrical reproducibility of the surface characteristics depends strongly on the plastic material deformation. Thus, the precise prediction of the emerging surface microstructures using kinematic simulation models is limited, because they ignore the influence of material flow. Consequently, the effects of plastic as well as elastic deformation are investigated in depth by finite element analysis. Microstructured surfaces resulting from these numerical models are characterized quantitatively by areal surface parameters and compared to those from a kinematical simulation and a real machined surface. A high degree of conformity between the values of the simulated surfaces and the measured values is achieved, particularly with regard to material distribution. Deficits in predictability exist primarily due to deviations in plastic deformation. Future research can address this, either by implementing a temperature consideration or adapting specific modeling aspects like an adjusted depth of cut or experimental validated material parameters. [ABSTRACT FROM AUTHOR]

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H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were studied. The failure modes, hysteresis curves, bearing capacity, ductility, energy dissipation capacity, stiffness degradation and strain distribution were discussed. The calculation method of structural theoretical internal force was presented. The results showed that the overall structural seismic performance was better, and the structural ductility met the demands of elastic-plastic inter-story drift angle for seismic design. The H-steel weak-axis connection structure obtained better energy dissipation capacity, and its bearing capacity and stiffness were slightly different from the strong-axis connection. The heat preservation and decoration performance of composite wallboard and the all-bolted connection of the steel frame realized prefabrication during the whole construction period. The plastic hinge of the steel beam can be moved outwards because of the L-angles, which effectively avoids stress concentration in joint areas and expands the plastic hinge range. The errors between the theoretical structural capacity calculated by the plastic analysis method and the test results were within 2.44%. In addition, structural failure mechanisms and bearing capacities were verified by the finite element (FE) analysis, and the effects of the main parameters on the structures were investigated. The FE verification results were the same as in the test. The research results provide theoretical support and technical guidance for the application of thermal insulation and decorative composite wall panels in H-shaped steel all-bolted steel frames. [ABSTRACT FROM AUTHOR]

A numerical simulation model of a natural ventilation greenhouse is helpful for improving the production and quality of greenhouse crops in tropical areas. Field experiments show that the mean coefficient of variation of indoor light intensity in four seasons was lower than 10.0%. The highest indoor temperature reached 39.3 °C during summer, while the average indoor temperature ranged from 24 °C to 26 °C in the other three seasons. The average relative humidity in the greenhouse ranged from 76% to 87% annually, which was higher and more stable than that in the external environment. A three-dimensional steady-state numerical model of the greenhouse was established based on computational fluid dynamics. Under natural ventilation conditions, the maximum error between the simulated value and the measured value of the temperature in each measuring point was 5.90%. And the average relative error between the simulated and measured values was 3.0% in the range of 0.7−1.5 m of crop cultivation height. Finally, a numerical simulation of adding side windows and expanding the vents was carried out. The results show that these methods can homogenize the airflow distribution in the greenhouse and improve the utilization efficiency of natural ventilation without more mechanical system operations. [ABSTRACT FROM AUTHOR]

Due to the increasing use and inadequate disposal of plastic by humans, aquatic environments have become receptacles for pollutants such as plastic. This study aimed to perform an analysis of plastic particles pollution in Brazilian aquatic ecosystems with special attention to inland aquatic environments and fish in order to identify information gaps in this field. Manuscripts published in the last 21 years and indexed in the Web of Science database were consulted. A total of 185 met the proposed inclusion criteria, such as having empirical data, being conducted in Brazil, and dealing with plastic pollution. In general, the number of studies increases over the years, and this increasing number of publications is accompanied by declared financial support; the Southeast and Northeast regions are the regions that publish the most on the topic, with São Paulo, Rio de Janeiro, and Pernambuco being the main states; the main focus of the studies is the detection of plastic particles mainly in biota (51%) and sediment (34%), and the most frequent ecosystem is the marine (89%); regarding the taxa, the majority is about plastic detection in fish (75%). Only 18% of the papers studying fishes consider their bio-ecological data, and only 17% of the manuscripts carried out the chemical characterization of the particles. However, 99% of the papers considered the shape of the plastic particle. We emphasize the need for more research and grants for studies with Brazilian inland aquatic ecosystems on the effects of plastic particle pollution on freshwater fish. Regional and national research funding agencies are very important to encourage an increase in the number of grants and specific calls for studies on plastic pollution and its impact on freshwater biota, considering the different macro-regions in Brazil, especially in the northern region. [ABSTRACT FROM AUTHOR]

Low computational efficiency and non-linearity behaviour make the simulation of the overall building structure problematic to attain with a single dynamic or static method. Thus, this paper uses a plastic deformation (PD) method based on concrete plasticity theory (CPT) for comparative analysis of multi-storey reinforcement cement concrete (RCC) and composite buildings under common and rare earthquake loads. For this purpose, a 15-storey tall building was selected for analysis using ABAQUS software. At first, a possible building model was created and then plastic deformation analysis was performed using the new PD method under both common and rare earthquakes. After that, a nonlinear time history analysis was conducted, and the results of plastic strain distribution, lateral displacement, peak acceleration, storey stiffness, shear force, storey drift, normalised shear, and top deflection of the RCC and composite buildings were studied deeply. The fundamental time period of the RCC model was found to be 5.2 s while the fundamental time period of the composite model was 6 s. Under common and rare earthquake leads, the peak acceleration of the RCC building was 19% and 22% higher than composite buildings, respectively. Under common and rare seismic loads, the top deflections of the composite building were 33% and 36% higher than those of RCC buildings, respectively. In the case of the RCC building, it was found in this study that higher peak acceleration (PA) of the ground motion led to higher storey top displacement, storey drift, shear force and top deflection under both ground motions. Numerical results suggested that the use of composite structure is more durable than RCC structure. It was also concluded that the PD method could also be effectively used for the analysis of RCC and composite buildings under dynamic loads. [ABSTRACT FROM AUTHOR]

The circular economy mostly relies on the reduction of fossil-based materials. Finding economically viable, low-cost, renewable, and biodegradable alternatives to plastic packaging is a significant challenge for this aim since it is widely used in the daily consumption of various products. Bioplastics are already considered promising substitutes for packaging materials since they are biodegradable, use renewable resources, and release fewer greenhouse gases. However, the shift from fossil-based to biobased materials also has its difficulties. This study uses qualitative data collected from three primary stakeholder groups of this transition, namely, R&D managers from the packaging industry, researchers, and policymakers. The research findings show that stakeholders are mostly in consensus regarding the advantages and challenges of the shift from fossilbased plastic to bioplastics. The knowledge and awareness of the process are highly compatible with the literature on the subject. Additionally, the findings suggest that although bioplastics have the potential to contribute significantly to sustainability goals and the circular economy greatly costs, lack of regulations, incentives and inadequate recycling infrastructure are major obstacles to change. The agreement of stakeholders on the matter of challenges also reveals the need for common ground for a solution. [ABSTRACT FROM AUTHOR]

Rivers are the main route for plastic entering the ocean, including the Musi River Estuary. Characteristics of bacteria that are able to degrade plastic waste through polymerase enzymes. The aim of this research is to determine the ability of bacterial isolates to degrade plastic and identify the types of bacteria that degrade plastic waste. This study used plastic bottles, nylon nets, and snack wrappers as objects for degradation measurement. Identification analysis of the 16S rRNA gene using universal PCR primers for bacteria in the form of forward primer 63f (5'-CAG GCC TAA CAC ATG CAA GTC-3') and reverse primer 1387r (5'-GGG CGG WGT GTA CAA GGC-3'). The type of bacteria with the highest percentage of degradation over 20 days, amounting to 7.75%, was Bacillus amyloliquefaciens. Identification of types of plastic degrading bacteria using 16S rRNA gene analysis showed 11 bacteria with 8 types including Staphylococcus hominis, Pseudomonas aeruginosa, Acinetobacter sp., Acinetobacter baumannii, Acinetobacter variabilis, Shewanella sp., Micrococcus luteus, and Bacillus amyloliquefaciens. The percentage of plastic degradation by bacteria is relatively small, so it is best to look for times where there is potential for bacterial growth. [ABSTRACT FROM AUTHOR]

Pollution by anthropogenic litter is a major threat to global ecosystems. Seabirds are frequently used as environmental monitors of litter ingestion, but similar research is rare for terrestrial birds. Here, we focused on pellet analysis from 117 nests of an iconic bird of the Western Palearctic, the white stork (Ciconia ciconia), breeding in southern and southwestern Poland in a farmland landscape, far away from large dumps and landfills. We found that most prey items in the diet of white storks were invertebrates (particularly from orders Coleoptera, Orthoptera, and Hymenoptera) but vertebrate prey comprised most of the biomass. Further analysis revealed that anthropogenic litter was found in 22.7% of pellets (34.2% of breeding pairs) with plastic (8.4%) and cigarette filters (6.9%) being most prevalent. This study represents the first assessment through pellet analysis of the ingestion of anthropogenic litter by live wild storks in Poland and also by a migratory population of white storks. Our study indicates a potentially significant transfer of plastic and other anthropogenic material through terrestrial food webs. [ABSTRACT FROM AUTHOR]

Plastics are now omnipresent in our daily lives. The existence of microplastics (1 μm to 5 mm in length) and possibly even nanoplastics (<1 μm) has recently raised health concerns. In particular, nanoplastics are believed to be more toxic since their smaller size renders them much more amenable, compared to microplastics, to enter the human body. However, detecting nanoplastics imposes tremendous analytical challenges on both the nano-level sensitivity and the plastic-identifying specificity, leading to a knowledge gap in this mysterious nanoworld surrounding us. To address these challenges, we developed a hyperspectral stimulated Raman scattering (SRS) imaging platform with an automated plastic identification algorithm that allows micro-nano plastic analysis at the single-particle level with high chemical specificity and throughput. We first validated the sensitivity enhancement of the narrow band of SRS to enable high-speed single nanoplastic detection below 100 nm. We then devised a data-driven spectral matching algorithm to address spectral identification challenges imposed by sensitive narrow-band hyperspectral imaging and achieve robust determination of common plastic polymers. With the established technique, we studied the micro-nano plastics from bottled water as a model system. We successfully detected and identified nanoplastics from major plastic types. Micro-nano plastics concentrations were estimated to be about 2.4 ± 1.3 × 105 particles per liter of bottled water, about 90% of which are nanoplastics. This is orders of magnitude more than the microplastic abundance reported previously in bottled water. High-throughput single-particle counting revealed extraordinary particle heterogeneity and nonorthogonality between plastic composition and morphologies; the resulting multidimensional profiling sheds light on the science of nanoplastics. [ABSTRACT FROM AUTHOR]

The problem statement is given and the algorithm for solving problems of plasticity for axisymmetric bodies made of isotropic materials with properties depending on a stress mode and plastic loosening is described. The constitutive equations of the theory of deformation processes along the trajectories of small curvature containing two nonlinear dependences are used. One of them implements the relationship between the first invariants of stress and strain tensors, and the other one implements the relationship between the second invariants of the corresponding deviators. The effect of the dependence of deformation curves on the stress mode and the plastic change in the bulk strain on the results of calculating the stress-strain state of the shell is studied. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to present a comprehensive knowledge mapping and an in-depth analysis of plastic and sustainability research to understand better global trends and directions in this field that emerged between 1995 and 2022. Design/methodology/approach: This study presents a visual analysis of 1933 research articles listed in the Web of Science (WoS) databases between the years 1995 and 2022 related to plastic and sustainability. The knowledge mapping based on CiteSpace and VOSviewer presents the current research status, which contains the analysis of the collaboration network, co-citation network, references with citation bursts and keyword analysis. Findings: The results reveal that China and the USA are the most prominent countries in exploring the notion of sustainability and plastic. The Chinese Academy of Science is the most prominent institution. Chai Qiang, Friedrich Daniel, Sahajwalla Veena and Ok Yong Sik are the most prolific authors in this field. Furthermore, circular economy, bioplastic, sustainable development, polyester and bioplastics are the highly discussed issues in recent years. Not surprisingly, COVID-19 is the latest topic of discussion started in 2021 due to its negative impact on plastic pollution and the challenges it posed to sustainability. Originality/value: This study is among the pioneers to shed light on the current research status of plastic and sustainability using the bibliometric method and the newest data. This study also suggests that collaborations between scholars and institutions require to be enhanced for better management of plastic pollution and to contribute to sustainable development. [ABSTRACT FROM AUTHOR]

Plastic entering the environment is a growing threat for ecosystems. We estimate the annual mass of known Dutch plastic waste generated and littered and where it ends up. We use two methods: (1) a material flow analysis of plastic waste separately collected from 13 economic sectors (including households, industry and imports) and estimate the amount sent to processing plants or exported and (2) a mismanagement model from observations of litter (on Dutch beaches and riverbanks) plus estimates of inadequately managed exported plastic scraps entering the environment abroad. In 2017 (the most recent complete data set available), an estimate of 1990 (±111) kilotonnes [kt] of plastic waste was separately collected. The top three plastic waste generating sectors (74% of the total) were households, clothing and textiles, and importation. Our mismanagement model estimates that 4.3–21.2 kt enters the environment annually; almost all of which occurs in foreign countries after inadequate management of imported Dutch waste. We highlight unknowns, including the source and/or destination of imported (623 kt) and exported (514 kt) plastics, plastics in non-household mixed waste streams and the plastic fraction of some separately collected waste, for example, e-waste. Our results stress the need for improved monitoring and reporting of plastic waste. Beyond the Netherlands, our recommendations could also help other high-income countries' decision-makers reach their circular economy goals. [ABSTRACT FROM AUTHOR]