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Purpose: To assess satisfaction and preference among rugby union players for custom mouthguards with and without labial reinforcement, and to assess discomfort and perceived protection. Materials and Methods: This prospective RCT used a crossover design of four 1-week periods to compare conventional (Type A) and labial reinforced (Type B) customized mouthguards for rugby union players from February to May 2022. Type B mouthguards included a 0.75-mm insert of polyethylene terephthalate glycol (Duran) in the anterior labial region. We ensured intraoral occlusion accommodation for both mouthguards. Players wore each mouthguard type when training and in competitive matches for 2 weeks according to one of two randomized sequences. After each session, they rated the mouthguard on 10-point scales regarding discomfort, functional interference, protection, and general satisfaction. After 4 weeks, we asked participants to nominate their preferred mouthguard. Results: In total, 22 of the 24 invited players (16 men and 6 women) were included. We observed no significant differences in discomfort, functional interference, protection, or general satisfaction by mouthguard type (P > .05, Wilcoxon test). Ultimately, 12 players (55%) preferred the Type A mouthguard and 10 (45%) preferred the Type B mouthguard (P = .832; one-sample binomial test). No serious adverse events occurred. Conclusions: Labial reinforcement does not affect satisfaction, perceived comfort and protection, or mouthguard preference among rugby union players. [ABSTRACT FROM AUTHOR]

In this work, a low-profile optical transparent wideband metamaterial absorber based on radiation–absorption reciprocal theory is proposed. The top layer and bottom layer are composed of indium tin oxide–polyethylene terephthalate films, and the middle layer is a transparent substrate polymethyl methacrylate. The method of transparent wideband absorption using reciprocal theory is proposed to guide the design. Based on characteristic mode analysis and calculated equivalent aperture efficiency, the absorber consisting of composite resonators is analyzed and designed. The equivalent circuit model and surface current distributions are studied to verify the design. The numerical results show that high absorption of greater than 90% in the frequency range of 5.7–16.4 GHz is obtained. A wideband absorption rate of greater than 80% at a 60° incident angle under TM polarization and an absorption rate of greater than 65% at a 60° incident angle under TE polarization are obtained. The proposed design has the advantages of broadband absorption, polarization insensitivity, light transmittance of more than 70%, and compact structure, which can be applied to special scenes that require optical transparency, such as anechoic chamber glass and cockpit glass. [ABSTRACT FROM AUTHOR]

Polypropylene double‐grafted maleic anhydride and bisphenol A epoxy resin (PP‐g‐M‐E) was successfully prepared by a single‐step method and characterized by Fourier‐transform infrared spectroscopy. Subsequently, it was employed as a compatibilizer to fabricate polypropylene (PP)/polyethylene terephthalate (PET) blends via melt extrusion. The content of the PET dispersed phase in the composite varied from 0 to 30 phr. The microstructure and morphology of the composites were characterized using scanning electron microscopy and Raman spectroscopy. The addition of PP‐g‐M‐E increased the interfacial interaction between the two phases and improved the compatibility and thermal stability of the system. In the presence of the compatibilizer, the crystallinity of the matrix phase (PP) increased, while that of the dispersed phase (PET) decreased owing to the heterogeneous nucleation effect of uniformly distributed PET. Double grafting of the PP‐g‐M‐E compatibilizer considerably enhanced the mechanical performance of the PP/PET blend system. The elongation at break of the modified sample exceeded that of the PP/PET blends by 117.55%, and the flexural and impact properties also showed considerable improvement. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) fabric was enzymatically modified with polyethylene glycol (PEG). Lipase from Aspergillus oryzae was used as a catalyst. The wetting behavior of the modified PET fabric was characterized by the water contact angle, water adsorption dynamics and moisture regain. The initial water contact angle of the modified fabric decreased from 129.3° to 74.9°. The water absorption dynamics results indicated that the equilibrium water absorption amount of the modified fabric was approximately 10 times greater than that of the untreated sample. The initial absorption rate (V init) of the modified fabric was almost 30 times higher than that of the untreated fabric. The moisture regain reached 3.52 % after modification. Scanning electron microscopy revealed granular and sheet coatings on the surface of the modified fabric. Chemical linkage of PEG onto the PET fibers was confirmed by attenuated total reflection–Fourier transform infrared spectroscopy. The modification had no significant effect on the thermal properties of the PET fabrics according to the thermogravimetric curve and differential scanning calorimetry results. The mechanical properties of the modified fabric were slightly improved. Therefore, in situ enzymatic transesterification between PET and PEG could be a potential novel modification approach for adding value to PET fiber textiles. [Display omitted] • Polyethylene glycol was chemically linked onto polyethylene terephthalate(PET) fiber. • PET fibers was hydrophilic modified by lipase-catalyzed transesterification reaction. • The water contact angle of modified PET fabric decreased from 129.3° to 74.9°. • The moisture regain of modified PET fabric reached (3.52±0.02)%. • The mechanical properties of PET fabric were slightly improved after modification. [ABSTRACT FROM AUTHOR]

Additive Manufacturing (AM) techniques, particularly Fused Filament Fabrication (FFF), have revolutionized prototyping and low-volume production. Improving the tensile properties of FFF-printed parts is a primary objective to elevate their functional utility. This study aimed to investigate the effects of annealing time (ATM), annealing temperature (ATP), and nozzle diameter (ND) on the tensile strength (TS) of two commonly used printing materials: Polyethylene Terephthalate Glycol (PETG) and PETG reinforced with carbon fibre (PETG-CF). Samples with varying ND (0.4 mm, 0.6 mm, and 0.8 mm) underwent annealing at ATP of 80°C and 100°C for ATM of 60 min and 120 min, respectively. Subsequent tensile tests were meticulously conducted, and regression models were employed to comprehensively analyse the influence of these control factors on TS. The findings from the tensile tests on annealed specimens revealed substantial improvements in TS for both PETG and PETG-CF materials. Statistical analysis, Taguchi method (TM), and response surface methodology (RSM) indicated that ND exerted a more pronounced impact on TS compared to ATM and ATP. By identifying the optimal control factor combinations for each material, the study pinpointed that the best TS was achieved at 0.8 mm ND, 120 minutes ATM, and 100°C ATP for PETG-CF. The remarkable enhancement in tensile properties for annealed FFF-printed parts underscores the potential of PETG-CF to replace structural metallic components in critical applications within the automotive and aeronautical industries. [ABSTRACT FROM AUTHOR]

In this work, 5‐ferrocenyl‐dipyrromethane (Fc‐DPM) synthesized from the pyrrole and ferrocenecarboxaldehyde condensation was electrochemically deposited on a gold (Au) electrode and used to remove metal ions found in rural waters. The structural analysis of Fc‐DPM was recorded by means of nuclear magnetic resonance (NMR) techniques. The Fc‐DPM was electrochemically coated on an indium tin oxide‐polyethylene terephthalate (ITO‐PET) surface, and the resulting Fc‐DPM/ITO‐PET was characterized using scanning electron microscopy (SEM)–energy dispersive X‐ray (EDX) analysis. The heavy metal and mineral content of four real water samples from the same rural area were determined by inductively coupled plasma mass spectrometry (ICP‐MS) before and after electrochemical removal. The proposed Fc‐DPM/Au electrode was successfully applied for aluminum ion (Al3+) and barium ion (Ba2+) removal for the first time, and the limit of detection (LOD) was calculated as 0.003 and 0.217 ppb for Ba2+ and Al3+, respectively. [ABSTRACT FROM AUTHOR]

The polyethylene terephthalate (PET) fibers surfaces were modified by complexing tannic acid (TA)-iron ions (Fe3+) to form a metal skeleton structure on the fibers. In this system a large number of phenolic hydroxyl groups, epoxy groups and other active groups on the fibers surfaces can stabilize the metal skeleton structure and enhance the interfacial peeling performance between the fibers and the composite rubber matrix. The modified PET fibers were analyzed by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and mechanical properties. The results showed that the peeling strength between the modified fibers and the rubber matrix was increased 45%. This method has the advantages of simple operation, mild conditions and low cost, which provides a new idea for the preparation of rubber/polyester fiber composites with excellent mechanical properties. [ABSTRACT FROM AUTHOR]

The interaction between particles and proteins is a key factor determining the toxicity responses of particles. Therefore, this study aimed to examine the interaction between the emerging pollutant polyethylene terephthalate micro/nanoplastics from water bottles with bovine serum albumin. The physicochemical characteristics of micro/nanoplastics were investigated using nuclear magnetic resonance, x‐ray diffraction, Fourier transform infrared, dynamic light scattering, and x‐ray energy dispersive spectroscopy after exposure to various concentrations and durations of protein. Furthermore, the impact of protein‐treated micro/nanoplastics on biological activities was examined using the mitochondrial activity and membrane integrity of A549 cells and the activity and biofilm production of Staphylococcus aureus. The structural characteristics of micro/nanoplastics revealed an interaction with protein. For instance, the assignment of protein‐related new proton signals (e.g., CH2, methylene protons of CH2O), changes in available protons s (e.g., CH and CH3), crystallinity, functional groups, elemental ratios, zeta potentials (−11.3 ± 1.3 to −12.4 ± 1.7 to 25.5 ± 2.3 mV), and particle size (395 ± 76 to 496 ± 60 to 866 ± 82 nm) of micro/nanoplastics were significantly observed after protein treatment. In addition, the loading (0.012–0.027 mM) and releasing (0.008–0.013 mM) of protein also showed similar responses with structural characteristics. Moreover, the cell‐based responses were changed regarding the structural and surface characteristics of micro/nanoplastics and the loading efficiencies of protein. For example, insignificant mitochondrial activity (2%–10%) and significant membrane integrity (12%–28%) of A549 cells increased compared with control, and reductions in bacterial activity (5%–40%) in many cases and biofilm production specifically at low dose of all treatment stages (13%–46% reduction) were observed. [ABSTRACT FROM AUTHOR]

While fluorescence‐based high‐throughput screening (HTS) has been valuable for identifying enzymes and microorganisms for polyethylene terephthalate (PET) depolymerization, the traditional approach relies on cleaving ester bonds in small‐molecule probes, limiting its ability to directly detect activity towards polymeric PET substrates. This study proposes a novel fluorescence‐based screening strategy for detecting the release of sulfhydryl groups during the depolymerization of pseudo‐PET polythioesters by polyester hydrolases. The strategy successfully identifies the polyester‐depolymerizing activity of leaf‐branch compost cutinase (LCCICCG), whereas porcine liver esterase (PLE) only hydrolyses small molecular substrates. Furthermore, the strategy can be integrated with a droplet microfluidic system for high‐throughput screening of LCCICCG. This work further demonstrates the applicability of the microplate reader platform for screening polyester‐depolymerizing bacteria. This novel fluorescence‐based approach offers an efficient strategy to identify enzymes and microbial resources for depolymerizing polyester‐like plastics. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) as one of non-degradable wastes has become a huge threat to the environment and human health. Chemical Recycle of PET is a sustainable way to release 1,4-benzenedicarboxylic acid (BDC) the monomer of PET as common used organic linker for synthesis of functional Metal-organic-frameworks (PET-derived MOFs) such as UiO-66, MIL-101, etc. This sustainable and costeffective "Waste-to-MOFs" model is of great significant to be intensively investigated in the past years. Attributes of substantial porosity, specific surface area, exposed metal centers, uniform structure, and flexible morphology render PET-derived MOFs are well-suited for applications in adsorption, energy storage, catalysis, among others. Herein, in the present work, we have summarized recent advances in synthesis of PETderived MOFs using ex-situ and in-situ methods for typical applications of adsorption, catalysis and energy storage. Despite those improvements in synthesis methods and potential applications, challenges still remain in development of green and economical routes to fully utilize waste PET for massive manufacture of valuable MOF materials and chemicals. This review provides insights into the conversion of non-degradable PET waste to value-added MOF materials, and further suggests promising perspectives to develop the sustainable "Waste-to-MOFs" model in addressing environmental pollution and energy crises. [ABSTRACT FROM AUTHOR]

Food packaging plays a crucial role in product storage, transportation and distribution. This study is dedicated to the development of high barrier blends for food packaging through the melt blending of polyethylene terephthalate (PET) and polyethylene 2,6‐naphthalate (PEN). The blends underwent comprehensive characterization involving chromaticity analysis, DSC, FTIR and XRD. Results indicated that the blend comprising 30 wt% PEN and 70 wt% PET exhibited superior structural properties, making it suitable for the production of beverage packing bottles. To evaluate the bottle properties, SEM, AFM, TG analysis and permeability testing were conducted. Comparatively, the barriers to O2, CO2, and water vapour of PEN/PET bottles were 3.52‐fold, 7.36‐fold and 2.25‐fold higher than PET bottles, and the mechanical properties and UV blocking properties have also improved. The PEN/PET bottles exhibited good thermal stability, with thermal shrinkage temperature and initial decomposition temperature at 87.5°C and 254°C, significantly higher than PET bottles (p < 0.05). Interestingly, the thermal shrinkage rate of PEN/PET bottles was measured at 87.5%, notably lower than that of PET bottles at 90.9%, indicating that PEN/PET bottles had good thermal stability. Additionally, beverage stored in PEN/PET bottles demonstrated lower dissolved oxygen content, suggesting promising applications for PEN/PET bottles in beverage packaging. [ABSTRACT FROM AUTHOR]

Plastics are used widely in almost every field of life, but their synthetic and persistent nature makes them harmful for the environment. The aim of this research was to evaluate the degradation abilities of Aspergillus niger, Candida albicans, and Acremonium sclerotigenum on microplastics (MPs). MP pieces of 4 ± 1 mm, including polyethylene, polyethylene terephthalate, and polystyrene, were incubated with fungal inoculums for 30 days. The degradation of treated MPs was determined by biofilm formation, weight loss, scanning electron microscopy (SEM), and Fourier transform analyses. The results indicated that the polyethylene MPs treated with Aspergillus niger exhibited the highest level of biofilm formation (optical density 1.595) and percentage weight loss (16%). In the case of polyethylene terephthalate and polystyrene MPs, Acremonium sclerotigenum and co‐culture showed weight loss of 6% and 10%, respectively. Candida albicans was observed to be the least effective in biodegradation analyses. SEM observation revealed the surface modifications as holes, pits, cracks, and increased roughness in treated MPs. Fourier transform infrared (FTIR) spectroscopy showed that the chemical structure of each polymer exhibited some variations. The study concluded that the fungal strains play an important role in the biodegradation of plastics and can be utilized to mitigate environmental pollution. [ABSTRACT FROM AUTHOR]

Plasmonic superstructures offer broad prospects in photothermal catalysis, yet their controllable synthesis remains a challenge. Here, a controlled synthesis method for Cu‐Ru plasmonic superstructures via a one‐step polyol reduction process is presented, where Cu nanoparticles serve as the core, while the shell is formed from Ru nanoclusters. Through a comprehensive investigation of the growth mechanism, precise control over the composition and size of the superstructures is achieved. Finite‐difference time‐domain  simulations and photothermal conversion experiments demonstrated that the optimized Cu3Ru1 superstructures possess strong light absorption capabilities and efficient photothermal conversion performance. These properties are effectively utilized in the photothermal recycling of waste polyethylene and polyethylene terephthalate, marking a significant advance in employing Cu‐based plasmonic materials for sustainable catalytic technology. [ABSTRACT FROM AUTHOR]

Multi‐layer plastic films are widely used in various fields especially for packaging, but due to complex composition, it is very difficult to recover single‐material polymers or high‐purity monomers from them after usage. In this study, we proposed a hydrothermal process for recycling PET/PE (PET: Polyethylene terephthalate; PE: Polyethylene) films. PET can be hydrolyzed to monomers of terephthalic acid (TPA) and ethylene glycol (EG). Using a hydrothermal system equipped with two filters, PE, TPA, and EG were collected separately, indicating the simultaneous material and chemical recycling of PET/PE films was firstly achieved. At 300 °C and 10 MPa for 60 min, PET conversion reached around 100 %, and TPA yield of 83.0 % was obtained with a high TPA purity of 96.1 %. In addition, the effect of the holding time on PET conversion, TPA yield, EG yield, and TPA purity was studied. This research opened up a new and sustainable pathway to recycle multi‐layer plastic films in both lab and industry. [ABSTRACT FROM AUTHOR]

Liquid fuel, such as 2,5‐dimethylfuran (DMF), from biomass, is an efficient, potential alternative to fossil‐based fuels due to its exceptional properties, including lower volatility, a remarkable octane number, heightened energy density, and immiscibility with water. DMF can be the starting substrate for producing bio‐based p‐xylene through the Diels‐Alder reaction with ethylene to produce biobased polyethylene terephthalate (PET). This review, thus, discusses the catalytic role of various precious and non‐precious metals on different supports, such as carbon, metal‐oxide, zeolite, and hydrotalcite, for the production of DMF via catalytic hydrodeoxygenation (HDO) of 5‐hydroxymethylfurfural (HMF) based on the previously reported literature. Various characteristic properties of the employed catalytic materials, such as particle size, metal‐support and substrate interaction, surface area, porosity, and acidic and basic sites, are delineated, playing a crucial role in the HDO of HMF to DMF. The influence of various reaction parameters, such as hydrogen atmosphere, solvents‐ including hydrogen donor solvents‐ and temperature are also discussed. [ABSTRACT FROM AUTHOR]

It is known that X‐ray CT of organic polymer materials usually provides low‐contrast images because of the low X‐ray absorption of these materials. In this paper, we describe a new method to enhance the contrast of X‐ray CT images of organic polymer materials. We demonstrate that gamma‐ray irradiation of poly (ethylene terephthalate) (PET) fibers in dichloromethane containing 2‐bromoethyl methacrylate, 2‐chloroethyl methacrylate, or 4‐bromostyrene results in the grafting of halogen‐containing oligomeric chains onto the PET fibers. Focused ion beam scanning electron microscopy (FIB‐SEM) and time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) analyses revealed a homogeneous distribution of bromine atoms within the 2‐bromoethyl methacrylate‐modified PET fibers, not only on the surface. This uniform incorporation translated to a significant improvement in X‐ray CT image contrast compared with pristine fibers. Similar treatment of polypropylene pellets also enhanced the contrast of their X‐ray CT images. This is a new simple and effective method to enhance the X‐ray CT image contrast and potentially applicable to various polymer materials including polymer composites and porous polymer materials, readily allowing the observation of their 3D microstructures finely. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) straps cannot be recycled in some regions. The aim of this paper was to evaluate an alternative for recycling discarded PET straps in concrete paving blocks. Fresh and hardened properties of the composite were tested for dosages containing 1%, 5% and 10% of shredded PET straps by total weight. Later, the environmental impacts of this recycling alternative were evaluated using the life cycle assessment (LCA) methodology. The increase of shredded PET straps content decreased slump, density and flexural strength of blocks, and a content of 5% of plastic had the lowest water absorption. All studied environmental impacts were reduced by increasing the amount of plastic content. Although shredded plastic straps could not improve the technological properties of concrete, except from water absorption, this recycling alternative could still be used to reduce environmental impacts of paving blocks production, substituting raw materials with up to 5% of plastic by weight. [ABSTRACT FROM AUTHOR]

The increased rate of postuse accumulation of the heteroatom‐containing plastic wastes, like polyethylene terephthalate (PET), polycarbonate (PC) and polyurethane (PU), in the environment propels the research for effective and sustainable valorization. In this study, PET from bottle waste, PC from compact discs, and PU from waste wind turbine blade were characterized and employed for fast pyrolysis experiments. Importantly, red mud (RM), a mixed oxide rich in Fe, Al, Si, Na, and Ca, was used as a catalyst for fast pyrolysis. The effects of temperature and feed/catalyst ratio on product yields were studied to elucidate the product formation mechanism. Benzoic acid and its derivatives, bisphenol‐A and oxygenated aromatics, and 4,4′‐methylenebisbenzamine were the major products obtained from the noncatalytic fast pyrolysis of PET, PC, and PU, respectively. The use of RM improved the yield of aromatic hydrocarbons from PET to 27.8 wt% at 550 °C, phenolics from PC to 46.6 wt% at 550  °C, and 4,4′‐methylenebisbenzamine to 34.9 wt% at 650 °C. The catalytic activity of RM is ascribed to the presence of active basic sites. The present study paves the path for the catalytic upcycling of challenging plastic wastes using industrial waste, like RM, as a sustainable catalyst from a circular economy viewpoint. [ABSTRACT FROM AUTHOR]

Ideonella sakaiensis is a bacterium that can degrade and consume polyethylene terephthalate (PET), a plastic material that was previously considered non‐biodegradable. The degradation of PET requires two enzymes, namely poly (ethylene terephthalate) hydrolase (PETase) and mono (2‐hydroxyethyl) terephthalate hydrolase (MHETase), which break down PET into terephthalate (TPA) and ethylene glycol (EG), which serve as carbon sources for the bacterium. Previous studies have focused on the enzymatic properties, structure, and mechanism of action of PETase and MHETase. However, the regulation of PETase and MHETase gene expression has not been investigated. This study identified a protein that binds to the MHETase promoter DNA, MHETase gene‐regulating protein (MRP) in I. sakaiensis. PET or TPA induced the expression of PETase and MHETase genes. Furthermore, the induction of the MHETase gene was abolished by the deletion of the mrp gene, while the expression of the PETase gene was maintained. In addition, the genes involved in TPA metabolism were not induced in the mrp mutant. Furthermore, the growth of the PET and TPA deteriorated due to mrp mutation. Also, MRP binds to the promoter regions of the MHETase gene and TPA metabolizing genes, but not to the PETase gene promoter. These results suggest that MRP is a transcription factor that activates MHETase and TPA‐metabolizing genes. [ABSTRACT FROM AUTHOR]

Despite considerable interest, uniform and robust flexible transparent conducting electrodes (FTCEs) that can be seamlessly integrated and used for highly efficient large‐area flexible oganic light‐emitting diodes (OLEDs) remain elusive. In this study, a large‐area fabrication of uniform transparent electrodes for high‐performance flexible OLEDs by exploiting the rapid nanowelding process of silver nanowires (AgNWs) onto polyethylene terephthalate substrate under Xe‐lamp irradiation and mechanical pressing treatment is reported. The performance of AgNWs FTCEs is significantly enhanced by applying the Xe‐lamp beam irradiation for 5 s and subsequent compression at 20 MPa for 15 s, achieving a low sheet resistance of 26.5 Ω sq−1, a high transmittance of 95.2% (at 550 nm), and very smooth surfaces with root‐mean‐square of 5.4 nm. Meanwhile, the nanowelded AgNWs FTCEs maintain excellent electrical conductivity (only a 2.96% increase in ΔR/R0) after 1000 bending cycles. The resulting AgNWs FTCEs‐based green phosphorescent OLED achieves an unprecedented external quantum efficiency (EQE) of 23.7% and a current efficiency as high as 81.5 cd A−1. Benefiting from the uniform properties for resulting AgNWs FTCEs, the fabricated flexible OLED with a large area of 25 × 25 mm2 still retains a high EQE of 22.2% and a current efficiency of 78.0 cd A−1. [ABSTRACT FROM AUTHOR]

AbstractRefractance window drying is a technique that has great potential to dry commodities, with better quality at an affordable cost. However, there is still a lack of awareness regarding its use and implementation in academic curricula as well as in industry. This study aims to design and develop a low-cost and effective Internet of Things (IoT) enabled Infrared (IR) assisted refractance window dryer. The effect of different flexible materials used as membranes with the same thickness was also investigated. Then, experiments were conducted on papaya pulp to study the performance of the developed dryer. The drying time (reduced moisture content up to 4%) was observed for the papaya pulp sample by employing Low-density polyethylene (LDPE), Polypropylene (PP), Polytetrafluoroethylene (PTFE), White Polyethylene Terephthalate (W-PET) and Transparent polyethylene terephthalate (T-PET) material as a membrane were 300, 330, 360, 330, and 300 min respectively. After thoroughly testing membrane materials properties, it is concluded that the T-PET membrane has superior thermal, mechanical, and optical properties. After an exhaustive examination of the marketplace scrutiny, the payback period was found to be 0.55 years. [ABSTRACT FROM AUTHOR]

Plastic pollution is one of the main worldwide environmental concerns. Our lifestyle involves persistent plastic consumption, aggravating the low efficiency of wastewater treatment plants in its removal. Nano/microplastics are accumulated in living beings, pushing to identify new water remediation strategies to avoid their harmful effects. Enzymes (e. g., Candida rugosa‐CrL) are known natural plastic degraders as catalysts in depolymerization reactions. However, their practical use is limited by their stability, recyclability, and economical concerns. Here, enzyme immobilization in metal‐organic frameworks (CrL_MOFs) is originally presented as a new plastic degradation approach to achieve a boosted plastic decomposition in aqueous systems while allowing the catalyst cyclability. Bis‐(hydroxyethyl)terephthalate (BHET) was selected as model substrate for decontamination experiments for being the main polyethylene terephthalate (PET) degradation product. Once in contaminated water, CrL_MOFs can eliminate BHET (37 %, 24 h), following two complementary mechanisms: enzymatic degradation (CrL action) and byproducts adsorption (MOF effect). As a proof‐of‐concept, the capacity of a selected CrL_MOF composite to eliminate the BHET degradation products and its reusability are also investigated. The potential of these systems is envisioned in terms of improving enzyme cyclability, reducing costs along with feasible co‐adsorption of plastic byproducts and other harmful contaminants, to successfully remove them in a single step. [ABSTRACT FROM AUTHOR]

This research aimed to investigate the effectiveness of Polyethylene-Terephthalate (PET) as a reinforcement material for sandy soils in enhancing the shear strength. To achieve this, different concentrations of PET were tested, and 118 sets of data were collected. Parameters such as relative density, normal stress in direct shear strength test, and types of PET elements (1 × 1, 1 × 5, and fiber) were also recorded. Subsequently, four decision tree-oriented machine learning (ML) methods—decision tree (DT), random forest (RF), AdaBoost, and XGBoost—were applied to construct models capable of forecasting enhancements in shear strength. The evaluation of these models' effectiveness was conducted using four established statistical metrics: R2, RMSE, VAF, and A-10. The results showed that AdaBoost results in the highest prediction accuracy among other algorithms, representing the high modelling performance of the algorithm in dealing with complex nonlinear problems. The conducted sensitivity analysis also revealed that relative density is the most crucial parameter for all the algorithms in predicting the output, followed by PET percentage and normal stress. Furthermore, to make the developed model in this study more practical and easy to use, a Graphical User Interface (GUI) was created, enabling the engineers and researchers to perform the analysis straightforwardly. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate glycol (PETG) is a novel amorphous shape memory polymer with excellent printability for 4D printing. In this article, ethylene‐vinyl acetate (EVA) is used as a biocompatible and non‐toxic copolymer to improve plasticity and shape memory performance of PETG. PETG‐EVA blends are prepared and 3D printed using a melt mixing method and an upgraded fused deposition modeling (FDM) with a pneumatic feeding system. The results of the thermal analysis show that the blends exhibit two tan‐delta peaks, each related to their components, and morphology images confirm that they are biphasic and immiscible with good compatibility. The morphology of both EVA10 and EVA30 matrix droplets is observed, with the droplets being larger for EVA30. The use of a pneumatic feeding system, along with the ability to control the output melt flow, results in the best printing ability for EVA30, with minimal microholes between the grids and interlayer cracks. The tensile strength of PETG‐EVA blends ranged from 25.38 to 20.14 MPa, with the highest tensile strength achieved for EVA30. The shape memory performance of all three blends is similar; with shape recovery exceeding 90% in 20 s. Blends with higher EVA content exhibited faster shape recovery within the first 10 s. [ABSTRACT FROM AUTHOR]

Anaerobic digestion (AD) is one of the most significant processes for treating fecal sludge. However, a substantial amount of microplastics (MPs) have been identified in septic tanks, and it remains unclear whether they impact the resource treatment of feces. To investigate this, polyethylene terephthalate (PET) was used as an indicator of MPs to study their effect on the anaerobic digestion of fecal sludge (FS). Two digestion systems were developed: FS mono-digestion and FS co-digestion with anaerobic granular sludge. The results indicated that the effects of PET varied between the two systems. PET inhibited volatile fatty acid synthesis in both systems, but the inhibition period differed. During mono-digestion, PET slightly increased gas and methane production, in contrast to the co-digestion system, where PET reduced methane production by 75.18%. Furthermore, in the mono-digestion system, PET increased soluble chemical oxygen demand and ammonia nitrogen concentrations while blocking phosphorus release, whereas the co-digestion system showed the opposite effects. Ultimately, the choice of digestion method is crucial for the resource utilization of septic tank sludge, and the impact of MPs on AD cannot be ignored. [ABSTRACT FROM AUTHOR]

In large format additive manufacturing (LFAM), a keener understanding of the relationship between the manufacture method and material temperature dependency is needed for the production of large polymer parts. Statistical analyses supported by material properties and a meso-structural understanding of LFAM are applied to elucidate tensile data trends. The data from LFAM polyethylene terephthalate glycol with 30% carbon fiber (CF) (PETG CF30%) panels (diagonal, horizontal, and vertical in the x-y print plane) and injection-molded specimens tensile tested at six different testing temperatures (room temperature, 40 °C, 50 °C, 60 °C, 70 °C, and 80 °C) were used for statistical analyses. A standard deviation, a coefficient of variation, and a two-way and one-way analyses of variance (ANOVA) were conducted. The manufacturing method (44.2%) and temperature (47.4%) have a strong effect on the ultimate tensile strength, in which temperature (82.6%) dominates Young's modulus. To explain the difference between the ultimate tensile strength of vertical, diagonal, and horizontal specimens at room temperature, a visual inspection of the specimen failure was conducted and the maximum stress at the crack tip was calculated analytically. The decreased strength in the diagonal specimens resulted from the reliance on interlaminar adhesion strength. Future work will consider the effect of the void space variation on tensile strength variance. [ABSTRACT FROM AUTHOR]

The rampant use of plastics, with the potential to degrade into insidious microplastics (MPs), poses a significant threat by contaminating aquatic environments. In the present study, we delved into the analysis of effluents from textile industries, a recognized major source of MPs contamination. Data were further discussed and compared with a municipal wastewater treatment plant (WWTP) effluent. All effluent samples were collected at the final stage of treatment in their respective WWTP. Laser diffraction spectroscopy was used to evaluate MP dimensions, while optical and fluorescence microscopies were used for morphology analysis and the identification of predominant plastic types, respectively. Electrophoresis was employed to unravel the prevalence of negative surface charge on these plastic microparticles. The analysis revealed that polyethylene terephthalate (PET) and polyamide were the dominant compounds in textile effluents, with PET being predominant in municipal WWTP effluents. Surprisingly, despite the municipal WWTP exhibiting higher efficiency in MP removal (ca. 71% compared to ca. 55% in textile industries), it contributed more to overall pollution. A novel bio-based flocculant, a cationic cellulose derivative derived from wood wastes, was developed as a proof-of-concept for MP flocculation. The novel derivatives were found to efficiently flocculate PET MPs, thus allowing their facile removal from aqueous media, and reducing the threat of MP contamination from effluents discharged from WWTPs. [ABSTRACT FROM AUTHOR]

Silicon oxide (SiOx) coatings are attracting significant attention and are widely used in industrial applications. They can be prepared by plasma-assisted chemical vapor deposition (PACVD). PACVD at atmospheric pressure (AP-PACVD) is often employed to synthesize SiOx coatings, but it has generally not been scaled up to an industrially viable level. In the present work, a SiOx coating was continuously deposited onto a polyethylene terephthalate film using industrial-scale roll-to-roll type AP-PACVD. 1,1,3,3-Tetramethyldisiloxane (TMDSO) and tetraethoxysilane (TEOS) were selected as precursors. The elemental compositions and chemical structures of the SiOx coatings were characterized, and oxygen and water-vapor transmission rates were measured. The SiOx coating using TEOS exhibited better barrier properties than that using TMDSO, corresponding to the high oxygen content, high SiO2 content, and high siloxane network content in the SiOx coating. [ABSTRACT FROM AUTHOR]

Objective: The biochip method allows microscale multiparametric analysis of macromolecular samples using a matrix of immobilized molecular probes. Selection of materials for biochip fabrication, functionalization of the carrier surface, and the method of immobilization of molecular probes are the key tasks of biochip technology. Methods: Methods of obtaining polymer coating from polyvinyl acetate on the surface of polyethylene terephthalate polymer substrates and subsequent production of brush polymers by photoinduced radical copolymerization of acrylate monomers have been studied. Cell matrices with numerous reactive chemical groups for subsequent immobilization of proteins were formed by photolithography method. Methods of activation of carboxyl groups on brush polymers attached to the surface of polyethylene terephthalate were tested. Immobilization of model protein streptavidin labeled with fluorescent dye Su3 was performed to test the method of activation of carboxyl groups. Results and Discussion: A variant of the immunofluorescence assay in a biological microarray format was tested on the model "streptavidin–biotinylated immunoglobulin." Conclusions: Streptavidin immobilized in brush polymer cells retains functionality and spatial accessibility for binding to biotinylated immunoglobulin and subsequent manifestation by antibodies fluorescently labeled with Cy5 dye, which opens prospects for the use of biological microarrays with brush polymer cells on polyethylene terephthalate substrates for immunofluorescence analysis of various protein targets. [ABSTRACT FROM AUTHOR]

Polaritons are generated by strong interaction between photons and matter, with the hybridization fundamentally changing the energy landscape of the system. Future exploitation of polaritons will benefit from implementing low‐cost, flexible, and easily tuneable configurations, as electronics have before. Here, coherent coupling of the carbonyl stretch vibrations of polyester (poly(ethylene terephthalate), PET) films to the optical modes of a Fabry–Perot (FP) cavity is presented, in which the FP cavity is directly formed on flexible, free‐standing, and commercially available PET films. For 2‐µm thick PET films, the carbonyl stretch vibration of the PET overlaps with the half‐wavelength FP cavity mode, leading to the coupling of the two modes, a Rabi splitting above 160 cm−1, and associated anticrossing in angular dispersion measurements. The study demonstrates dynamic control of light‐matter interaction strength by modulating film thickness under tension, finding that a 25% tensile stretch can tune the light‐matter interaction from 20:80 mixing to near‐perfect 50:50 hybridization at normal incidence. These findings are discussed in the context of future foldable/twistable/wearable polaritonic devices. [ABSTRACT FROM AUTHOR]

The current investigation evaluates the compressive response of 3D-printed carbon fiber-reinforced PETG thermoplastics to optimize different infill parameters when loaded at high impact pressures (strain rates). The selected parameters for the 3D printing of different samples are the filling pattern (rectilinear and honeycomb) and the filling density (25%, 50%, and 75%). Compression-split Hopkinson pressure bars (SHPBs) combined with a high-speed camera were used to monitor the evolution of the mechanical behavior and damage kinetics of 3D-printed samples in real-time with the variation in strain rate. The results revealed a significant improvement in compressive strength and compressive modulus when the filling density was increased from 20% to 75% for both patterns. However, the combination of a honeycomb pattern with 75% filling presented the best compressive strength, stiffness and damage resistance, irrespective of impact pressure. In particular, the highest compressive strengths, ranging from 35.5 to 56.16 MPa for impact pressures of 1.4 to 2.4 bar, respectively, were obtained with this configuration (75% honeycomb pattern). This represents a substantial difference of 25 to 38% compared with the 75% rectilinear pattern, which showed values below 35 MPa. Another significant result was observed for the compressive modulus, which reached 2787.8 MPa for the honeycomb-filled samples, whereas this value remained below 2000 MPa for the rectilinear pattern. [ABSTRACT FROM AUTHOR]

Microplastic pollution in water samples from Kartepe Avluburun and Gebze Denizli drinking water treatment plants in Kocaeli, Turkey, was investigated for the first time. In Kartepe Avluburun, the particle abundance in raw, treated, and tap water samples ranged from 1579 to 5283 (mean: 3117) particles per liter, 637.5 to 2274 (mean: 1317) particles per liter, and 758.5 to 2485 (mean: 1476.6) particles per liter, respectively; whereas these results for Gebze Denizli were 786.5–3388 (mean: 1882), 397.5–2226 (mean: 1028), and 470–2821 (mean: 1256.8). Similar microplastics removal efficiency was determined in both treatment plants at all seasons except spring. In fall season, a peak removal efficiency of 76.3% was achieved. The prevalent polymer types of microplastics in the raw water were polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, and polyamide. The most common microplastic sizes in the samples were between 1 and 20 μm (82%), the color was blue, and the shape was fragment type. [ABSTRACT FROM AUTHOR]

Chemical degradation of PET with natural rubber was carried out. The product obtained was characterized by FTIR, and it was found that the intensity of the vibration signal of the carbonyl group (1719 cm−1) depends on the mass of rubber used in the reaction and not on the PET degradation products, reaching an adequate mass ratio of Rubber/PET = 4. The chemical structure of the product obtained was rubber chains with end groups of ethylene terephthalate oligomers. The pasting properties of the banana starch were modified with the resulting product, affecting its gelatinization process and the maximum viscosity value of 5.78 Pa.s to 1.50 Pa.s at a temperature of 25 °C. Starch degraded PET-rubber films have better mechanical properties than starch-only films. Additionally, these films degrade at lower temperatures (491 to 469 °C) than starch-only films. The ability of these films to conduct electrical current increases up to 25.52% with respect to that of the native starch film. SEM morphology of the starch degraded PET-rubber films shows the formation of clusters, which causes the films to present adhesive characteristics, indicating that these films have a high potential for application in the adhesive and paint industry as biodegradable materials. [ABSTRACT FROM AUTHOR]

Enzymatic degradation of poly(ethylene terephthalate) (PET) into its corresponding monomers provides an attractive route for green plastic recycling and environmental remediation applications. However, the binding of PET hydrolases toward the PET surface is a rate-limiting step in PET degradation. Hence, we selected three anchor peptides and four linker peptides to fuse the previously engineered leaf-branch compost cutinase for facilitating enzyme binding and improving degradation of real post-consumer PET wastes of Coca Cola and C′eastbon PET bottles, with using the amorphous PET as a control. The systematical characterization of the seven cutinases revealed that the anchor peptide with moderate hydrophobicity plus chaperone activity and the flexible linker peptide with small hydrophobicity but long length were more suitable for each domain to serve its own role, affording the facilitated PET binding affinities and enhanced PET degradation performance. Thus, the optimal fusion cutinase possessed up to 3.3 times higher catalytic efficiency (k cat / K m) and 76 % increased long-term degradation performance than the parental cutinase, respectively. Further, complete degradation of C′eastbon PET wastes and 77 % degradation of Coca Cola PET wastes were achieved by the optimal cutinase of 33.3 nmol·g−1 PET in 96 h, proving its superiority against the real post-consumer PET wastes. [Display omitted] • Varying anchor and linker peptides were fused to an engineered variant of cutinase. • Real polyethylene terephthalate (PET) wastes were degraded by seven cutinases. • Effects of anchor and linker peptides on enzymatical PET degradation were explored. • Catalytic efficiency was enhanced 3.3 times by the optimal fusion strategy. • Optimal cutinase of 33.3 nmol·g−1 PET completely degraded C′eastbon PET wastes in 96 h. [ABSTRACT FROM AUTHOR]

Invisible orthodontic treatments are becoming increasingly popular, and numerous brands of invisible aligners are now available. However, concerns remain about the safety of the materials used in these products. This study aimed to assess the cytotoxic effects of both original and thermoformed thermoplastic materials used in orthodontic aligners on human periodontal ligament (HPDL) cells in vitro. The experiment used six different brands, each containing three types of thermoplastic materials, Polyethylene terephthalateco-1, 4-cyclohexylenedimethylene terephthalate (PETG), thermoplastic polyurethane (TPU), and copolyester polyethylene terephthalate (PET). The original sheets and the thermoformed materials were soaked in a culture medium for seven and fourteen days, and then applied to cultured human periodontal ligament cells. Cells were harvested on the first, third, and fifth days after application, and their viability was analyzed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. The findings revealed that some thermoformed materials, notably PETG, exhibited lower survival rates compared to their non-thermoformed versions. However, other materials such as TP and PET maintained over 70% cell viability, indicating only minor cytotoxic effects. These findings highlight the need for further research into the long-term biocompatibility of these materials but generally affirm their safety for use in orthodontic aligners under the tested conditions. [ABSTRACT FROM AUTHOR]

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Recently, 3D printing of large, structural polymer parts has received increasing interest, especially for the creation of recyclable structural parts and tooling. However, the complexity of large-scale 3D polymeric printing often dictates resource-intensive trial and error processes to achieve acceptable parts. Existing computational models used to assess the impact of fabrication conditions typically treat the 3D-printed part as a continuum, incorporate oversimplified boundary conditions and take hours to days to run, making design space exploration infeasible. The purpose of this study is to create a structural model that is computationally efficient compared with traditional continuum models yet retains sufficient accuracy to enable exploration of the design space and prediction of part residual stresses and deformations. To this end, a beam-based finite element methodology was created where beads are represented as beams, vertical springs represent inter-bead transverse force transfer and multi-point, linear constraints enforce strain compatibility between adjacent beads. To test this framework, the fabrication of a large Polyethylene terephthalate glycol (PETG) wall was simulated. The PETG was modeled as linearly elastic with an experimentally derived temperature-dependent coefficient of thermal expansion and elastic modulus using temperature history imported from an ABAQUS thermal model. The results of the simulation were compared to those from a continuum model with an identical material definition, showing reasonable agreement of stresses and displacements. Further, the beam-based model required an order of magnitude less run time. Subsequently, the beam-based model was extended to allow separation of the part from the printing bed and the inclusion of part self-weight during fabrication to assess the significance of these effects that pose challenges for existing continuum models. [ABSTRACT FROM AUTHOR]

The recycling of polyethylene terephthalate (PET) waste plastics has garnered global attention as an essential area of research to address. Chemical upcycling methods, such as glycolysis, offers a visible solution by directly converting PET wastes into high-valued monomers, enabling their reintegration into the plastic life cycle. However, the recovery of metal salt catalyst and the thermal stability of organic catalyst pose challenges in PET glycolysis. Zeolites with strong Brønsted acid are widely used in the degradation of polyolefins, but in PET glycolysis, they face the problems of acid site mismatch and difficult contact with PET. In this work, nanosized FAU-type zeolite catalysts (100-FAU) were employed to carry out PET glycolysis, which were green synthesized at low temperature without organic template. In comparison to commercial FAU-type catalysts, 100-FAU exhibits enhanced Lewis acidity and basicity along with increased accessibility to active sites. The 100% degradation of PET was achieved within 1 h, resulting in a BHET yield of 64.2%. Prolonging the reaction time to 1.5 h led to an enhanced BHET yield of 72.1%. The quality of the primary product bis(2-hydroxyethyl) terephthalate (BHET) was verified through IR, DSC, and NMR characterizations. Furthermore, as a solid catalyst with high thermal stability, zeolite can be easily recovered via filtration and demonstrated stable performance over at least 5 cycles, and proved effective for glycolysis of commercially waste PET plastics. The acid–base dual-functional catalytic mechanism of Na-form FAU in PET glycolysis was proposed. Under its guidance, the promoting effect of other Na-form nanosized zeolites on PET degradation was verified. [ABSTRACT FROM AUTHOR]

This study tackles the growing global concern about municipal waste management, particularly in cities like the Grand Guayaquil Metropolitan Area (GGA). Through realistic field studies on in situ household waste generation and geographic information system (GIS) tools, this work offers a framework to predict the quantities and types of recyclable household waste for any metropolitan area in Latin America. Over 4 weeks, students collected, sorted and weighed recyclable waste types, including plastic, paper, metal, glass and fabric, from 776 sampled household of the GGA. ArcGIS survey tool identified household locations and allowed to survey different socio-demographic features. With the help of ArcGIS interpolation method, the total household waste generation for GGA was predicted, and the classification of the different types of recyclable waste was also spatially distributed for the study area. The report identified notable trends in plastic waste, specifically polyethylene terephthalate waste's steady prevalence and 42% growth rate, emphasizing the importance of enhanced recycling techniques. Spatial density maps showed a heterogeneous waste distribution across the GGA, emphasizing locations with higher waste output. This study demonstrates that improving recyclable waste collection can be accomplished with a moderately cheap expenditure by collaborating with academia to overcome knowledge gaps. This strategy provides opportunities to mitigate the environmental impacts of poor waste management. [ABSTRACT FROM AUTHOR]

Customization of spacer fabrics to have the desired compression resistance and resilience is critical to promote their technical applications. The compression properties are mainly determined by the mechanical features of monofilaments used as spacer yarns. This study investigates the compression properties of spacer fabrics knitted with different polymeric monofilaments by analyzing their compression stress at 40% strain, residual strain, and energy absorption from cyclic compression tests. The monofilaments in the fabrics before and after cyclic compression were unraveled to test their tensile properties and morphologies for interpreting their different fabric compression properties. It was found that knitting monofilaments substantially alters their macroscopic and/or microscopic structures, thereby affecting the mechanical behavior of spacer monofilaments, and having different fabric structures and compression properties. Knitting polyethylene terephthalate monofilament damages the mesophase and induces a two-thirds decline in Young's modulus, while knitting polyamide 6 and polybutylene terephthalate monofilaments largely alters the macrostructures but maintains their good resilience. Spacer fabrics knitted with stiffer polyethylene terephthalate monofilaments have superior compression resistance but inferior compression resilience, while those knitted with softer and more resilient polyamide 6 and polybutylene terephthalate monofilaments have better compression resilience. Polyethylene monofilament is not suitable for spacer fabrics because of its low Young's modulus and poor tensile resilience. Polyethylene terephthalate spacer fabrics have the best compression resistance–resilience balance in terms of compression stress at 40% strain and residual strain in the fourth cycle required by the standard EN ISO 3386-1, while polyamide 6 and polybutylene terephthalate monofilaments are more suitable for long-term service due to their high compression resistance and resilience. [ABSTRACT FROM AUTHOR]

Polymeric wastes, specifically polyethylene terephthalate (PET) and scrap tyre rubber (STR), pose a significant environmental issue. PET, a thermoplastic polymer, is widely used in manufacturing bottles, PET cups, containers, fibres, films, and packaging materials. On the other hand, colossal rubber tyre waste quantities represent other environmental problems. However, PET and STR wastes are often discarded in the immediate vicinity, contributing to water resource pollution and landfill site strain. One solution is to replace aggregates in concrete mixtures with these wastes, a preferable alternative to landfill disposal because of the large volume and slow decomposition rate in landfills. Recycling PET and STR helps mitigate environmental pollution and promotes resource conservation and sustainability. This study aims to review previous research undertaken in the field and validate the findings of concrete’s fresh, mechanical, and functional characteristics. Based on the review, most studies confirmed a noticeable decline in the mechanical characteristics of mortar and concrete. However, these studies did not effectively focus on using PET and STR as sound and thermal insulation aggregates. Replacing PET and STR as aggregate in concrete can reduce thermal conductivity and acoustics. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: In recent decades, there has been significant advancement in scholarly research focused on detecting pollutants in marine environments and assessing the potential risks associated with seafood, particularly marine fish. The advancement has been predominantly influenced by the detection of microplastics, which have the ability to permeate food webs via both direct and indirect pathways. Microplastic pollution poses a substantial health risk to organisms at all levels of the food chain, including humans, who are top consumers. Despite the global concern, there is a lack of extensive research on microplastics in fish in Indonesia. The reliance of coastal communities in Indonesia on marine resources raises concerns regarding the potential impact of microplastic contamination. This study sought to assess the extent of microplastic pollutants in commercially caught marine fish from Jakarta Bay, a densely populated and industrialized coastal area accommodating more than 35 million inhabitants. METHODS: The study was conducted at five nearby fresh seafood markets in the northern part of Jakarta, where marine fish specimens were collected between December 2023 and January 2024. In total, 160 samples were gathered, with 20 individuals representing each of the eight diverse marine fish species. The approved protocol for extracting microplastics, which incorporates biological digestion, density separation, and microplastic identification, was strictly followed, although some adaptations were made as the process unfolded. Preventative actions were enacted in order to decrease the risk of microplastic cross-contamination. FINDINGS: It was determined through analysis that 93.75 percent (150 out of 160) of the fish studied contained microplastics, which were detected in samples obtained from both the gut and gill samples. On average, each fish had 3.65 ± 2.34 particles per individual, or approximately 0.12 ± 0.21 particles per gram. Microplastics were found in 81.25 percent of gut samples and 79.38 percent of gill samples. The abundance of microplastics in gut (1.79 ± 1.19 particles per individual) was slightly lower than in gills (1.86 ± 1.30 particles per individual). The variance in microplastic content between the two organs did not reach statistical significance. Fish with carnivorous feeding habits demonstrated a higher average microplastic content when contrasted with those utilizing omnivorous and planktivorous feeding strategies. Fish living in the benthopelagic region tended to have slightly more microplastic particles than those in benthic coastal water and pelagic coastal water. Most of the microplastics detected in commercial marine fish were in the size range of 2000-5000 micrometers, with the majority being in the form of fragments and fibers. The study also pinpointed seven specific polymer classifications, which consist of polyethylene, polypropylene, polystyrene, nylon, polyester, polybutadiene, and polyethylene terephthalate. CONCLUSION: The escalating levels of microplastics in the environment present a substantial threat to food security, marine ecosystems, and human health. It is imperative to develop a standardized risk assessment mechanism utilizing advanced tools and methodologies to quantify the levels of microplastics in the environment and living organisms as the study moves forward. It is imperative that both capture fisheries and aquaculture undergo thorough assessments of risks and hazards. This study underscores the significance of monitoring plastic waste in the Greater Jakarta area and its adjacent coastlines. Further study is essential to evaluate the magnitude of plastic pollution in fish tissues that are consumed by humans, and to assess the potential consequences for food safety. [ABSTRACT FROM AUTHOR]

The disposal of plastic materials in recent years has increased exponentially due to human activity. Thus, the accumulation of these residues represents a major concern due to the impact that has been observed, mainly in freshwater aquatic environments and their biota. This study aimed to analyze the presence of microplastics in the gills of fish from the Sorocaba River basin, relating the natural history of the species and the rivers where they were collected. 98 gill samples from eight species sampled at 9 different points of the 4 main Rivers of the basin were analyzed. A total of 385 particles were found, the majority being fibers (74%), predominantly black (63%) and sizes ranging from 2 to 5 mm. The presence of microplastics was verified in all individuals studied, as they are highly susceptible to exposure and retention of plastic microparticles. The highest occurrence of microparticles in fish occurred in the Tatuí River, being verified in the Principal Component Analysis (PCA), considered one of the most disturbed Rivers in the evaluated basin. The particles were identified as polyethylene, polyester, polymethyl methacrylate and polyethylene terephthalate. The present study showed that the gills constitute an important microplastic transfer route for freshwater fish species, and the ecological traits of the species may explain differences in contamination. Considering space–time sampling and different species that make up the fish community is vitally important to understand the scale of microplastic contamination and, subsequently, take effective mitigation measures. [ABSTRACT FROM AUTHOR]

Plastics are manufactured for various purposes but result in microplastic pollution in aquatic ecosystems. Riverine microplastic occurrence, spatial distribution, and impact have been globally documented but not well understood in Africa. We quantified 36 984 microplastics in riverbed sediment and river water along the Olifants and Sabie rivers, Kruger National Park (KNP), South Africa. These rivers have independent catchments. The microplastic profiles (size, polymer, morphotype, and colour) differed significantly between rivers. Riverbed sediment microplastic (mostly beads) concentrations ranged between 2022 to 9971 n/kg dm, and 2237 to 27 259 n/kg dm, for the Olifants and Sabie rivers respectively. Microplastic (mostly fragments) concentrations in river water ranged between 11 to 50 n/L in the Olifants River, and 4.0 n/L to 41 n/L in the Sabie River. Polyethylene terephthalate (PET) was prevalent in sediment (39%) and water (32%). Concentrations varied along both river stretches but the expected concentration decrease downstream was not observed. This raises transboundary concerns, as all the KNP rivers cross into Mozambique and from there into the Indian Ocean. Given the pervasive plastic pollution already present, there is a need for significant upstream and in-park interventions to reduce the concentration of microplastic in rivers flowing through conservation areas. [ABSTRACT FROM AUTHOR]

The distribution and composition of microplastics (MPs) in sediments provide a useful reflection of overall MP pollution for urban river systems. Sediment samples were collected from the Jinjiang River, the main tributary of the Minjiang River, to articulate the sources, distribution, and risk status of MPs. The results showed that the MPs in Jinjiang sediments were composed of polypropylene (PP), polyethylene (PE), polyethylene glycol terephthalate (PET), polystyrene (PS), and Rayon, with per kilogram of dry sediment (n/kg) ranged from 21 to 924 particles, and PP and PE were accounted for more than. MPs varied in colour, shape and size (100–5000 µm), although those observed were predominantly green, fragmented and about 1,000–5,000 µm. The dominant sources of MPs in sediments could be domestic waste and laundry effluents. The risk assessment for MPs showed that upstream and downstream were at moderate risk, while midstream was at low risk. This study can provide a reference for the management and control of MP pollution in urban rivers. [ABSTRACT FROM AUTHOR]

A modified polyol process was used to produce low-cost silver nanowires, which were analyzed using surface plasmon resonance, x-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. These nanowires were used to create silver ink with specific properties suitable for inkjet and aerosol printing. The ink's electrical resistivity was 140 µΩ cm on paper and 200 µΩ cm on polyethylene terephthalate and polypropylene. [ABSTRACT FROM AUTHOR]

The visual pressure chamber was designed. The pressure inside chamber can be measured and controlled. The camera can record the process of defoaming through the glass. To quantitatively study the relationship between defoaming rate and pressure, it is necessary to ensure that the morphology and size of the bubbles studied are basically the same. This article explores a bonding method of PET film that can control the diameter deviation of the bubbles within ±10 % for easy experimental comparison, while also eliminating bubbles through conventional processes without irreversible effects. The experiment found that below the critical pressure, the pores hardly undergo deformation. Above the critical pressure, the rate of pore contraction exhibits a positive correlation with the pressure. Through theoretical analysis, one mathematical model has been abstracted to represent the compression behavior of pores under pressure. In Abaqus, the simulation of the defoaming process was conducted using an explicit dynamic fluid cavity model. The simulated results obtained using the fluid cavity model in Abaqus are generally consistent with the experimental observations. When the film and bubbles are subjected to pressure, the film overcomes its own strength and undergoes a brief elastic deformation, and then begins a nonlinear change. At the same time, the internal space of the bubbles begins to shrink. When PET film is subjected to pressure, the deformation starts from the middle and gradually diffuses towards both sides. The internal air pressure of the bubbles increases until a state of mechanical equilibrium is reached. [ABSTRACT FROM AUTHOR]

Isolated Fe–Nx sites coupled with Fe3C nanoparticles co-embedded in N-doped porous carbon were fabricated using polyethylene terephthalate wastes as carbon sources. Benefiting from the synergistic effect between Fe–Nx sites and Fe3C, and the hierarchical porous structure, the catalyst exhibits outstanding ORR performance, realizing the concept of turning trash into treasure. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are considered pollutants of emerging concern. In rivers, MPs (=5 mm) are transported by currents and deposited in lakes, reservoirs, estuaries, and oceans. In Mexico, MPs in freshwater ecosystems have been scarcely studied. This work aimed to determine the presence of MPs in rivers of the Sierra Gorda Biosphere Reserve (SGBR). Samples of surface water and sediment collected from the Escanela, Jalpan, Ayutla, and Santa María rivers were processed. MPs in water were extracted by direct filtration using nitrocellulose filters with a 1.2 µm pore size; MPs in sediments were extracted by density suspension using a ZnCl2 solution (p ≈ 1.5 g/cm3). The surface of MPs was examined using SEM-EDX, and spectra of trace elements deposited on the MPs were obtained; additionally, MP polymers were characterized with FTIR. Fibers were the most abundant MP forms in both matrices. Up to 110.87 items L-1 were detected in water and 175 items kg-1 (dry weight) in sediments. Surface wear of MPs was observed, and trace elements were detected, including Al, Fe, Cr, Si, and Zn, among others. The polymers identified in MP samples were polyethylene terephthalate, polyester, polypropylene, high-density polyethylene, polyamide, and polystyrene. The test results revealed the presence of MPs with trace metals on their surface in the freshwater ecosystems of the SGBR, which may be related to mining operations in the study area, changes in land use, wastewater discharges, atmospheric transport, and dry and wet deposition. These findings demonstrated the ubiquity of these pollutants and their presence even in areas intended for conservation. [ABSTRACT FROM AUTHOR]