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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]

The deployment of fifth-generation mobile network (5G), beyond 5G and sixth-generation mobile network platforms encounters challenges of blockage, interference, and path loss in radio mobile environments. Metasurfaces provide a promising solution to address these limitations. In this paper, we present a methodology for developing ultrathin flexible metasurface-based frequency selective surfaces (FSSs). Our approach combines thermal evaporation for metallic thin films with a macroscopic metasurface mask (something analogous to screen-printing but using thermal evaporation instead of inks). As a proof of concept, we fabricate a sub-6 GHz metasurface-based FSS using gold deposition on a flexible polyethylene terephthalate substrate. Experimental results are validated through numerical full-wave simulations using COMSOL Multiphysics and equivalent-circuit model simulations. The metasurface operates within the primary frequency band utilized in 5G networks (3–5 GHz), indicating its potential applicability across a wide range of flexible, conformal, and wearable devices. The fabricated FSS can be installed on surfaces of any shape, such as flat or curved windows, as well as on walls or other external surfaces. This methodology offers practical solutions for wireless communications and enhancing signal transmission in diverse environments. [ABSTRACT FROM AUTHOR]

In this work, the oxygen barrier property of polyethylene terephthalate (PET) films was enhanced by optimizing the 'active' and 'passive' synergistic barrier approaches, that is, integration of high barrier material polyethylene naphthalate (PEN) and oxygen scavengers along with catalyst with PET before biaxially stretching the PET blended films. When the PEN content in the PET blended films reached 50wt%, the oxygen permeability coefficient was significantly reduced to 0.9687 cc*mil*[m.sup.-2]*[day.sup.-1] 0.1 [MPa.sup.-1], showing an enhancement of 117.4 times compared to the pure PET film. Furthermore, the water vapor permeability coefficient was reduced to 8.0208 g*mil*[m.sup.-2]*[day.sup.-1], representing a 45.5% reduction in comparison to the pristine PET film. It also maintained a higher transverse and longitudinal tensile strength (110.5 and 127.2 MPa) than PET film only with oxygen scavengers and catalyst (53.5 and 78.0 MPa). This work presents a viable and practical approach to endow PET materials with simultaneously enhanced oxygen, water barrier performance, and mechanical property. Highlights * The OPC of PET film was as low as 0.9687 cc*mil*[m.sup.-2]*[day.sup.-1]*0.1 [MPa.sup.-1]. * The 'active' and 'passive' barrier techniques together reduced the OPC of PET film. KEYWORDS blow molding, oxygen barrier, oxygen scavenging, polyethylene naphthalate, polyethylene terephthalate, water barrier, 1 | INTRODUCTION Polyethylene terephthalate (PET) is widely used as a thermoplastic polyester in food packaging due to its excellent mechanical property, affordability, as well as high transparency. (1,2) Although [...]

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]

Glycolysis of waste polyethylene terephthalate (PET) is a green and high-value PET recovery approach, the product of which can be used as raw materials to prepare polyurethanes. Enhancing the conversion rate and monomer selectivity of PET glycolysis through the development of efficient catalysts is crucial for reducing both the energy consumption and operational costs associated with the process. In this study, a series of deep eutectic solvents (DESs) were synthesised based on L-proline (Pro) and its derivatives and used as catalysts for the glycolysis of PET using 1,4-butanediol (BDO). Under the optimized reaction conditions (5.0 g PET, 25.0 g BDO, 2 wt% Pro/Zn(Ac)2 catalyst, 210 °C, 15 min and atmospheric pressure), PET was degraded completely, and the yield of monomeric bis(4-hydroxybutyl)terephthalate (BHBT) reached 67.1%. Based on the results of in situ-IR, ¹H NMR and density functional theory (DFT), the possible catalytic mechanism of DESs synergistically promoting PET depolymerization was proposed. Finally, aromaticbased polyurethane elastomers (PUEs) were prepared with PET glycolysis products bis(2-hydroxyethyl) terephthalate (BHET) and BHBT as chain extenders. Compared with the control group, the thermal and mechanical properties of aromatic-based PUEs were improved, which proved the feasibility of high value utilization of PET glycolysis products. [ABSTRACT FROM AUTHOR]

Microfluidic systems combine multiple processing steps and components to perform complex assays in an autonomous fashion. To enable the integration of several bio-analytical processing steps into a single system, valving is used as a component that directs fluids and controls introduction of sample and reagents. While elastomer polydimethylsiloxane has been the material of choice for valving, it does not scale well to accommodate disposable integrated systems where inexpensive and fast production is needed. As an alternative to polydimethylsiloxane, we introduce a membrane made of thermoplastic elastomeric cyclic olefin copolymer (eCOC), that displays unique attributes for the fabrication of reliable valving. The eCOC membrane can be extruded or injection molded to allow for high scale production of inexpensive valves. Normally hydrophobic, eCOC can be activated with UV/ozone to produce a stable hydrophilic monolayer. Valves are assembled following in situ UV/ozone activation of eCOC membrane and thermoplastic valve seat and bonded by lamination at room temperature. eCOC formed strong bonding with polycarbonate (PC) and polyethylene terephthalate glycol (PETG) able to hold high fluidic pressures of 75 kPa and 350 kPa, respectively. We characterized the eCOC valves with mechanical and pneumatic actuation and found the valves could be reproducibly actuated >50 times without failure. Finally, an integrated system with eCOC valves was employed to detect minimal residual disease (MRD) from a blood sample of a pediatric acute lymphoblastic leukemia (ALL) patient. The two module integrated system evaluated MRD by affinity-selecting CD19(+) cells and enumerating leukemia cells via immunophenotyping with ALL-specific markers. [ABSTRACT FROM AUTHOR]

With isophorone diisocyanate and polytetrahydrofuran as basic raw materials, dimethylolpropionic acid and 2,3‐dihydroxypropanesulfonic acid triethylamine salt (DHPSTEA) as chain extension agents, trimethylolpropane as crosslinking agent, N, N‐dimethylethanolamine as neutralizer, the high‐solid carboxylate/sulfonate waterborne polyurethane (SC‐HWPU) was synthesized. The effect of COO−/SO3− molar ratio on the properties of SC‐HWPU was studied. Fourier transform infrared and x‐ray photoelectron spectroscopy results demonstrated that the SC‐HWPU molecular chain contained carboxylate and sulfonate groups. The results of thermogravimetric analysis, dynamic mechanical analysis, and mechanical properties of SC‐HWPU film indicated that higher DHPSTEA content was favorable for the thermostability and mechanical properties when the total dosage of hydrophilic groups was invariable. When the mole ratio of COO−/SO3− is 8:2, the solid content of the prepared SC‐HWPU3 emulsion can reach to 51.6%, which has excellent storage stability and alkali resistance stability. Subsequently, the application of SC‐HWPU emulsion on the fixed‐island type polyamide/polyethylene terephthalate copolymer superfine fiber non‐woven fabric single‐coating process was analyzed, and the water‐base superfine fiber non‐woven fabric was prepared. Scanning electron microscopy showed that there was still a large amount of SC‐HWPU filled in the superfine fiber gap after alkali‐decrement, indicating that SC‐HWPU has excellent alkali resistance. [ABSTRACT FROM AUTHOR]

3,4‐Dihydroxy‐L‐phenylalanine (DOPA) serves as a post‐translational modification amino acid present in mussel foot proteins. Mussels exploit the exceptional adhesive properties of DOPA to adhere to a wide range of surfaces. This study presents the development of sticky proteins and bacteria through the site‐specific incorporation of DOPA using Genetic Code Expansion Technology. Through the optimization of the DOPA incorporation system, proteins containing DOPA demonstrate significantly improved binding abilities to various organic and metallic materials. The material‐binding capabilities of DOPA to combat different types of biofoulings are harnessed by integrating it into intrinsically disordered proteins. Beyond the creation of adhesive proteins for anti‐biofouling purposes, this highly efficient DOPA incorporation system is also applied to engineer adhesive bacteria, resulting in a remarkable increase in their binding capability to diverse materials including 400 folds of improvement to polyethylene terephthalate (PET). This substantial enhancement in PET binding of these bacteria has allowed to develop a unique approach for PET degradation, showcasing the innovative application of Genetic Code Expansion in cell engineering. [ABSTRACT FROM AUTHOR]

• 16 different types of PET trays from LWP and SP's samples were characterised. • Composition of PET tray as packaging objects, polymers, contaminants was determined. • Mechanical and chemical recyclability assessment of PET trays was implemented. • A few less common PET trays are suitable to obtain rPET through mechanical process. • For the most common PET trays the more appropriate recycling is depolymerisation. The compositions of Dutch lightweight packaging waste (LWP) and sorted products named "PET (Polyethylene terephthalate) trays" have been determined on object level. Additionally, the PET trays from both waste types were sorted in 16 categories representing their packaging use and material build-up. The material composition of at least 10 representative trays from each category was determined with chemical and thermal analysis, based on which the average material composition per category was established. Based on this data the average material composition of sorted PET tray products was approximated. The recyclability of the various categories of PET trays was assessed based on their material build-up. The most ubiquitous PET trays in Dutch LWP and sorted products were only found to be suitable to produce opaque recycled PET with mechanical recycling processes. Whereas only some more uncommon PET trays can be used to produce transparent recycled PET with mechanical recycling processes. Depolymerisation is deemed to be a more appropriate recycling process that will allow the production of transparent food-grade recycled PET. [ABSTRACT FROM AUTHOR]

From both economic and environmental perspectives, ethylene glycol, the principal constituent in the degradation of PET, emerges as an optimal feedstock for microbial cell factories. Traditional methods for constructing Escherichia coli chassis cells capable of utilizing ethylene glycol as a non-sugar feedstock typically involve overexpressing the genes fucO and aldA. However, these approaches have not succeeded in enabling the exclusive use of ethylene glycol as the sole source of carbon and energy for growth. Through ultraviolet radiation-induced mutagenesis and subsequent laboratory adaptive evolution, an EG02 strain emerged from E. coli MG1655 capable of utilizing ethylene glycol as its sole carbon and energy source, demonstrating an uptake rate of 8.1 ± 1.3 mmol/gDW h. Comparative transcriptome analysis guided reverse metabolic engineering, successfully enabling four wild-type E. coli strains to metabolize ethylene glycol exclusively. This was achieved through overexpression of the gcl, hyi, glxR, and glxK genes. Notably, the engineered E. coli chassis cells efficiently metabolized the 87 mM ethylene glycol found in PET enzymatic degradation products following 72 h of fermentation. This work presents a practical solution for recycling ethylene glycol from PET waste degradation products, demonstrating that simply adding M9 salts can effectively convert them into viable raw materials for E. coli cell factories. Our findings also emphasize the significant roles of genes associated with the glycolate and glyoxylate degradation I pathway in the metabolic utilization of ethylene glycol, an aspect frequently overlooked in previous research. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is a conventional packaging material. Its modification has attracted immense attention in the industry and academia. Here, office waste paper, white cardboard waste, and waste corrugated paper were first employed as raw materials for cellulose nanocrystal (CNC) extraction by acid hydrolysis. Thereafter, CNC/PET composite films with various CNC additions were prepared via a self‐assembly technique. The results revealed that the CNCs formed a self‐assembled film on the PET surface via the synergistic effect of the complex interactions among the CNCs as well as between the CNCs and PET. Moreover, the CNCs improved the barrier property of PET and decreased the oxygen and water vapor transmittances of CNC/PET by 30.7% and 21.7%, respectively. Additionally, the coating of the PET surface with 0.2 wt.% CNCs extracted from the waste paper decreased the surface wettability of PET, exhibiting application potentials in the hydrophobic modification of polymers. This study realized waste paper recycling and provided a basis for constructing self‐assembled functional films on PET surfaces. The findings and insights of this study could exhibit application potentials in the fields of waste recycling and packaging materials. Highlights: A functional cellulose nanocrystal (CNC) film is prepared from waste paper.Self‐assembled CNC is coated on a PET surface to form a CNC/PET composite film.The synergistic interactions among CNCs and between CNC and PET modified PET.The low addition of CNCs realized the efficiency modification of PET.The study achieves waste paper recycling and high‐value utilization. [ABSTRACT FROM AUTHOR]

Introduction: The development and optimization of novel diagnostic imaging prototypes heavily rely on experimental work. In radiology, this experimental work involves the use of phantoms. When testing novel techniques to demonstrate their advantages, anthropomorphic phantoms are utilized. The aim of this study was to investigate seven materials for 3D printing to replicate the radiological properties of breast lesions. Methods: To achieve this objective, we utilized three fused filament fabrication materials, namely, polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), and polyethylene terephthalate glycol (PET-G), along with resins such as White v4 Resin, Flexible 80A v1 Resin, Model v2 Resin, and Wax40 v1 Resin, to 3D print seven irregularly shaped lesions. These lesions were used to prepare a set of seven physical phantoms, each filled with either water or liquid paraffin, and one of the printed lesions. The phantoms were then scanned using a mammography unit at 28 kVp. Additionally, six computational breast phantoms, replicating the shape of the physical phantoms, were generated. These computational models were assigned the attenuating properties of various breast tissues, including glandular tissue, adipose tissue, skin, and lesions. Mammography images were generated under the same experimental conditions as the physical scans. Both the simulated and experimental images were evaluated for their contrast-to-noise ratio (CNR) and contrast (C). Discussion: The results indicated that the studied resins and filament-based materials are all suitable for replicating breast lesions. Among these, PLA and White v4 Resin exhibited the densest formations and can effectively approximate breast lesions that are slightly less attenuating than glandular tissue, while ABS and Flexible 80A v1 Resin were the least dense and can represent fat-containing breast lesions. The remaining materials provided good approximations for malignant lesions. These materials can be utilized for constructing phantoms for experimental work, rendering the model a valuable tool for optimizing mammography protocols, ensuring quality control of mammography X-ray equipment, and aiding in the diagnosis and assessment of breast cancer. [ABSTRACT FROM AUTHOR]

A new type of hybrid polymer particles capable of carrying the cytostatic drug doxorubicin and labeled with a gallium compound was prepared. These microparticles consist of a core and a hydrogel shell, which serves as the structural matrix. The shell can be employed to immobilize gallium oxide hydroxide (GaOOH) nanoparticles and the drug, resulting in hybrid beads with sizes of approximately 3.81 ± 0.09 μm. The microparticles exhibit the ability to incorporate a remarkably large amount of doxorubicin, approximately 0.96 mg per 1 mg of the polymeric carrier. Additionally, GaOOH nanoparticles can be deposited within the hydrogel layer at an amount of 0.64 mg per 1 mg of the carrier. These nanoparticles, resembling rice grains with an average size of 593 nm by 155 nm, are located on the surface of the polymer carrier. In vitro studies on breast and colon cancer cell lines revealed a pronounced cytotoxic effect of the hybrid polymer particles loaded with doxorubicin, indicating their potential for cancer therapies. Furthermore, investigations on doping the hybrid particles with the Ga-68 radioisotope demonstrated their potential application in positron emission tomography (PET) imaging. The proposed structures present a promising theranostic platform, where particles could be employed in anticancer therapies while monitoring their accumulation in the body using PET. [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]

Polyethylene terephthalate (PET), a widely used polymer in the production of single-use plastics, is a significant contributor to the global plastic pollution problem. This work explores the synergistic effects between clay matrices and active Nb 2 O 5 catalytic species, emphasizing the enhanced catalytic performance for the aminolytic depolymerization of PET and polyester (PES) wastes. The materials were well characterized using XRD, SEM-EDS, FTIR, and UV-DRS studies. The surface parameters of Nb 2 O 5 were enhanced by forming a composite with kaolin, which is confirmed by BET isotherms. Kaolin provides a large surface area, which enhances the dispersion and interaction of the niobia catalyst. The combination of kaolin and niobia acts as an effective catalyst for the depolymerization of PET, breaking down the polymer into its monomeric constituents. The catalytic efficiency of Nb 2 O 5 (82 %) has been enhanced in the presence of kaolin support (95 %), forming depolymerized bis(2-hydroxyethyl)terephthalamide (BHETA) and excellent reusability and stability of up to five subsequent cycles thereby emphasizing their potential for sustained performance in industrial applications and contributing to the ongoing discourse on advancing catalyst technologies for enhanced environmental impact in the circular economy. [ABSTRACT FROM AUTHOR]

Spent lithium‐ion batteries (LIBs) are an essential secondary resource containing valuable metal elements. Transforming spent LIBs into efficient catalysts through a simple process presents a promising strategy to address both metal resource scarcity and clean energy challenges. Herein, a deep eutectic solvent‐assisted synthesis of Co3O4 material from spent LIBs is proposed. The obtained Co3O4 material possesses efficient and stable electrocatalytic activity for converting raw polyethylene terephthalate (PET) bottles into high‐purity formic acid and terephthalic acid products under ambient conditions. As expected, the Co3O4 catalyst exhibits a high FE of 92 % with a concentration of produced potassium formate of 23.6 mM under alkaline conditions. This study presents a waste‐treating‐waste strategy for the simultaneous recovery of spent LIBs and PET waste in a greener manner. [ABSTRACT FROM AUTHOR]

Background: Coronaviruses, a group of highly transmissible and potentially pathogenic viruses, can be transmitted indirectly to humans via fomites. To date, no study has investigated their persistence on carpet fibers. Establishing persistence is essential before testing the efficacy of a disinfectant. Methods: The persistence of BCoV and HCoV OC43 on polyethylene terephthalate (PET) and nylon carpet was first determined using infectivity and RT-qPCR assays. Then, the disinfectant efficacy of steam vapor was evaluated against both coronaviruses on nylon carpet. Results: Immediately after inoculation of carpet coupons, 32.50% of BCoV and 3.87% of HCoV OC43 were recovered from PET carpet, compared to 34.86% of BCoV and 24.37% of HCoV OC43 recovered from nylon carpet. After incubation at room temperature for 1 h, BCoV and HCoV OC43 showed a 3.6 and > 2.8 log10 TCID50 reduction on PET carpet, and a 0.6 and 1.8 log10 TCID50 reduction on nylon carpet. Based on first-order decay kinetics, the whole gRNA of BCoV and HCoV OC43 were stable with k values of 1.19 and 0.67 h− 1 on PET carpet and 0.86 and 0.27 h− 1 on nylon carpet, respectively. A 15-s steam vapor treatment achieved a > 3.0 log10 TCID50 reduction of BCoV and > 3.2 log10 TCID50 reduction of HCoV OC43 on nylon carpet. Conclusion: BCoV was more resistant to desiccation on both carpet types than HCoV OC43. Both viruses lost infectivity quicker on PET carpet than on nylon carpet. Steam vapor inactivated both coronaviruses on nylon carpet within 15 s. [ABSTRACT FROM AUTHOR]

For the upcycling of waste polyethylene terephthalate (PET), encompassing both colored and fabric PET materials, we investigated the Ir(triNHC)‐catalyzed dehydrogenative coupling of PET and methanol, leading to the production of sodium lactate with good yields. We proposed a sustainable method for isolating lactic acid from the catalytic reaction mixture of sodium lactate and regenerating the base using bipolar membrane electrodialysis (BMED). This isolation method demonstrated high effectiveness, achieving isolation of lactic acid while maintaining economic feasibility at $ 0.10 per kg of lactic acid, and enabling sustainable NaOH regeneration with complete resource circulation. We assessed the recyclability of the catalyst and elucidated the mechanism involving base‐mediated depolymerization and catalyst‐promoted dehydrogenation, highlighting the importance of triNHC ligands in enhancing catalytic activity. [ABSTRACT FROM AUTHOR]

In addition to sportswear and outdoor equipment, moisture-absorbent quick-drying fabrics are also widely used in everyday clothing and home textiles. In this study, three types of weft-knitted fabrics were designed using Coolmax fiber and polypropylene fiber. The Coolmax/PP fabric exhibits good stretchability with a strain of 180.5% and achieves a high cumulative individual transfer capability of 691.6%, with a water absorption rate of 50.2%/s. The moisture conductivity gradient presented good moisture and heat conductivity in a simulated human body temperature environment using an infrared camera. Furthermore, mathematical modeling was constructed and visual simulation analysis was conducted to explore moisture–thermal transfer behavior. The simulation results closely align with experimental data, providing insights into designing flexible and wearable quick-drying fabrics for thermal management. [ABSTRACT FROM AUTHOR]

Cryogenics is the science and technology of very low temperatures, typically below 120 K. The most common applications are liquified natural gas carriers, ground-based tanks, and propellant tanks for space launchers. A crucial aspect of cryogenic technology is effective insulation to minimise boil-off from storage tanks and prevent frost build-up. Rigid closed-cell foams are prominent in various applications, including cryogenic insulation, due to their balance between thermal and mechanical properties. Polyurethane (PU) foam is widely used for internal insulation in cryogenic tanks, providing durability under thermal shocks and operational loads. External insulation, used in liquified natural gas carriers and ground-based tanks, generally demands less compressive strength and can utilise lower-density foams. The evolution of cryogenic insulation materials has seen the incorporation of environmentally friendly blowing agents and bio-based polyols to enhance sustainability. Fourth-generation physical blowing agents, such as HFO-1233zd(E) and HFO-1336mzz(Z), offer low global warming potential and improved thermal conductivity. Additionally, bio-based polyols from renewable resources like different natural oils and recycled polyethylene terephthalate (PET) are being integrated into rigid PU foams, showing promising properties for cryogenic applications. Research continues to optimise these materials for better mechanical performance and environmental impact. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is widely used in plastic bottles, packaging, and textile fibers. However, PET is difficult to degrade in nature and rapidly accumulates into the environment, causing serious environmental pollution and threatening human health. At present, the recycling methods for PET mainly focus on physical recycling and chemical degradation, but these methods have severe limitations, resulting in the great loss of valuable materials and secondary pollution. In contrast, the biodegradation of PET is gradually attracting attention because of its environmental friendliness, high efficiency, and cost-effectiveness. Several PET-degrading enzymes (PDEs) have been previously identified, such as cutinase, IsPETase, lipase, and esterase. Thereafter, many efforts have been made to push the boundaries of evolution schemes, attempting to create stronger PDEs with improved activity and stability. Nevertheless, most of these enzymes show preferences toward low-crystallinity (<10%) PET, while in situ enzymatic degradation of high-crystallinity PET (30%–50%) remains a major challenge. Exploring and engineering PDEs that can efficiently degrade bottle-grade PET plastics has recently become a research hotspot. This review systematically introduces the current advances in PDEs and emphasizes the role of metagenomics in screening and identifying new PDEs. [ABSTRACT FROM AUTHOR]

This paper describes California bearing ratio (CBR) tests carried out to investigate the suitability of waste polyethylene terephthalate (PET) bottles for ground improvement. For the studies, quarry dust is used as an infill, and it is prepared at a relative density of 57.6% within the CBR mould with a diameter of 150 mm. Experiments are carried out by embedding cut PET bottles with a diameter of 5.6 cm within the infill to provide cellular confinement in three different configurations, i.e. three-bottle, four-bottle and five-bottle configurations. The effect of bottle height on the performance of the systems is investigated by considering three cell (bottle) heights, viz., 6.6 cm, 9.3 cm and 11.6 cm. To analyse the performance of the cellular confinement, vertical stress distribution below the applied load is determined. It is observed that the performance of the PET bottle embedded system is better when it is placed within the isobar (σz/q) of 0.3. Based on the CBR values and improvement factor, it is observed that a four-bottle configuration with a height of 6.6 cm is effective in sustaining higher loads. The proposed study provides guidelines for using these bottles for stabilising blocked pavements. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are one of the major substantial pollutants in the environment and are stored in sediments worldwide, especially in marine environments. This study shed light on the abundance, distribution, sources and chemical composition of MPs present in the surface sediments collected from the shelf part of the southeast coast of India, Bay of Bengal. A total of twenty-seven surface sediment samples were collected to study MPs pollution. The abundance and morphological characteristics of MPs were determined by counting using an Olympus SXZ7 stereo microscope. Raman spectroscopy analysis was used to identify the polymer type of the MPs. The average abundance of MPs in the study area is 460±275 MPs/kg in dry sediment. Regarding colour, transparent particles were predominant (46.42%), followed by blue, green, brown, etc. With respect to particle shape and size, fibres and 500-µm sized MPs are abundant. Polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polystyrene (PS) are the polymer types characterised in the study area. The higher abundance of MPs in the study area can be attenuated to human interruptions, viz., tourism, fishing and inappropriate sewage disposal in the marine environment. In addition to this, population density also plays an important role in providing MPs to the marine environment. This study provides the most valuable data to extrapolate the research for mitigating MP pollution in oceans. It also informs mankind about their disastrous activities on the marine environment, which is expected to recuperate quickly and negatively impact human health and the functionality of the marine system. [ABSTRACT FROM AUTHOR]

1,4-Butanediol, an important chemical raw material, especially as the monomer of engineering plastic polyethylene terephthalate (PBT), plays a pivotal role in contemporary chemicals. A promising parallel approach is the linear-selective hydroformylation of inexpensive allyl acetate, which is economical yet challenging. Herein, we describe an atom-economic approach characterized by high selectivity for synthesizing 4-oxobutyl acetate through rhodium-catalyzed hydroformylation using allyl acetate. This protocol affords the intermediate of valuable 1,4-butanediol in excellent yield (up to 95%) and exhibits excellent regioselectivity (linear/branched up to 164) under mild conditions (60 °C, 10 bar of syngas), effectively minimizing the formation of decomposed byproducts. The success of this protocol hinges on the use of a "Rh/POP-type ligand" in combination with either acetic acid or bulky anionic salts as additives. Preliminary mechanism studies show that the use of CH3COOH facilitates the formation of a tridentate κ3-P,O,P-coordination, which prevents the coordination of carbonyl with the Rh center, leading to the relatively high linear selectivity of 4-oxobutyl acetate. Furthermore, the successful application of this protocol in synthesizing 4-oxobutyl acetate at a scale of 3.8 g, employing low Rh-loading (0.05 mol%), highlights its potential for industrial applications. [ABSTRACT FROM AUTHOR]

We examined the distribution characteristics of atmospheric microplastics in typical desert agricultural regions, with a focus on the agricultural areas surrounding the Taklamakan Desert, Xinjiang, China. We collected samples of total suspended particulate matter (TSP), atmospheric deposition, and atmospheric dust using both active and passive collection methods. The chemical composition, particle size, shape, and color of atmospheric microplastics were examined using a stereomicroscope and a Fourier‐transform infrared spectrometer to analyze their characteristics. The results showed that the primary chemical compositions of microplastics included polypropylene (PP), polyethylene, polyethylene terephthalate, polymethylmethacrylate, and cellophane. Particle sizes were mainly within the range of 0 to 1000 μm. Fibrous microplastics constituted the majority of the TSP and atmospheric deposition, whereas film‐like microplastics constituted the largest proportion of atmospheric dustfall. The deposition flux of atmospheric microplastics in the first quarter was measured at 103.21 ± 22.12 particles/m2/day, which was lower than that observed in conventional agricultural areas. The abundance of microplastics in atmospheric dustfall was found to be 1.36 particles/g. The proportion of PP microplastics in atmospheric dustfall can be as high as 35%. Through a comparison of microplastic content in TSP during dust storms and under normal weather conditions, it was found that dust storms can lead to an increase in the abundance of microplastics within the atmospheric TSP. The present study provides a scientific basis for understanding the distribution of atmospheric microplastics in typical desert agricultural regions. Environ Toxicol Chem 2024;43:1982–1995. © 2024 SETAC. [ABSTRACT FROM AUTHOR]

Nano-plastics have been found in snow and evidence shows that they can act as nuclei. The aerosol water-uptake ability is an important property that will determine wet deposition, a potential main route for nano-plastics to fall to the ground. In this work, we measure the hygroscopicity of three nano-plastics: low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polyvinyl chloride (PVC), and a fourth compound, cellulose, with in-situ aerosol techniques via a cloud condensation nuclei counter. Cellulose is a high-molecular weight compound and a main component of commonly used paper products. Ultrafine nano-plastic particles in the range of 20 to 200 nm are explored. Nano-plastic materials LDPE, PET, and PVC form droplets more readily than cellulose nanoparticles. The high hygroscopicity of nano-plastics indicates that the nano-plastics are either oligomers or a polymer with properties for water adsorption. Furthermore, a single parameter hygroscopicity, κ, derived from different droplet activation models (Flory Huggins Köhler and Frenkel-Halsey-Hill adsorption theory) are reported. Moreover, the molecular weights of the leached oligomers are predicted by Flory Huggins Köhler theory assuming ideal polymer mixing. The observed intrinsic hygroscopicity is size-dependent, hence the adsorption-based hygroscopicity model could be applied. Nano-plastics can be incorporated into clouds, transported globally, and may also be removed from the atmosphere via wet deposition processes. The analysis of hygroscopicity help estimating the lifetime and transport of nano-plastic particles in the atmosphere. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is a known substance that is found in food contact materials as an intentionally added as well as a non-intentionally added substance. Traces of BPA were found as a non-intentionally added substance in recycled PET (rPET). In 2023, the EFSA proposed a new TDI of 0.0002 µg/kg bw/d, which is lower than the previous (temporary) TDI of 4 µg/kg bw/d by a factor of 20,000. The TDI of 0.0002 µg/kg bw/d would translate for a default 60 kg person eating one kilogram of food into a migration limit of 0.012 µg/kg in the food. This very low migration limit is a challenge to measuring BPA levels in food. A solution is to use migration modeling to establish maximum concentrations in rPET for different food contact applications. Precise diffusion coefficients for BPA in PET were determined within this study by use of migration kinetics. In June 2024, the European Commission proposed a new migration threshold limit for BPA of 1 µg/kg, which should be understood as a detection limit. From the results of this study, it can be concluded that a BPA concentration in the PET bottle wall of 297 mg/kg (3% acetic acid), 255 mg/kg (10% ethanol), and 192 mg/kg (20% ethanol) after storage for 365 d at 25 °C is in compliance with the migration threshold limit of 1 µg/kg. These maximum concentrations are far above the measured BPA concentrations on rPET bottles in Europe between 2019 and 2023. Therefore, the new proposed migration threshold limit for BPA cannot be exceeded. [ABSTRACT FROM AUTHOR]

The research addresses challenges in food safety related to the migration of contaminants from plastics to food. It focused on the physicochemical and sensory degradation of olive oils packaged in polyethylene terephthalate (PET) and subjected to thermal exposure at 40 °C and 60 °C for several weeks and a subsequent 12 months of storage, as well as the stability and migration of compounds from the PET packaging itself. Olive oils (OO) from Spanish supermarkets (a mixture of refined and virgin, with commercial identifications of mild and intense) were selected and subjected to thermal treatments at 40 °C and 60 °C for 1, 2, and 3 weeks, followed by 12 months of storage. The treatments were conducted through the following two independent experiments: Experiment A focused on immediate analysis post-thermal treatment, while Experiment B included a 12-month storage period post-thermal treatment. The presence of antimony (Sb) was analyzed using acid digestion with nitric acid (HNO3) and high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS), while the metals cadmium (Cd), copper (Cu), lead (Pb), and iron (Fe) were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The PET characterization was assessed using Fourier transform infrared spectroscopy in the mid-infrared range (FT-IR/MIR), carbonyl index, and differential scanning calorimetry (DSC). The results showed increases in the acidity index by 0.29%, the peroxide value by 25.92%, and the K268 coefficient by 51.22% between the control sample and the most severe treatments, with more pronounced effects observed after 12 months. Sensory quality declined, with reduced intensity of the "fruity" attribute and increased presence of the "rancid" defect. PET degradation was reflected in an increase in the carbonyl index and greater structural amorphization. Fe was the predominant metal, and Sb concentration increased after thermal treatments. The lack of studies on the raw consumption of oils packaged in PET and the concerns about the migration of compounds from the packaging to the food highlight the relevance of this research. This study provides new insights into the effects of thermal exposure and storage on the migration of PET contaminants into oils, contributing to the development of strategies to ensure food safety and product quality. [ABSTRACT FROM AUTHOR]

Periosteal expansion osteogenesis (PEO) is a technique for augmenting bone by creating a gradual separation between the bone and periosteum. This study assessed PEO‐induced bone formation around the femurs of rats using a dynamic frame device (DFD), consisting of a shape memory membrane made of polyethylene terephthalate (PET) formed into a tubular shape. The DFDs, consisting of a PET membrane coated with hydroxyapatite (HA)/gelatin on the bone‐contact surface, were inserted between the periosteum and bone of the femurs of rats. In the experimental group, DFDs were suture‐fixed to the femur with 4–0 Vicryl Rapid; in the control group, 4–0 silk thread was used for fixation. Five rats per group were euthanized at intervals of 3, 5, and 8 weeks postoperatively. Bone formation was evaluated via micro‐CT imaging, histomorphometry, and histological analysis. Morphological analysis revealed new bone between the femur and the periosteum, expanded by the DFD, in all groups. The mean values of new bone were 0.30 mm2 proximally, 0.18 mm2 centrally, and 0.82 mm2 distally in the control group, compared to 1.05 mm2 proximally, 0.27 mm2 centrally, and 0.84 mm2 distally in the experimental group. A significant difference in new bone was observed in the proximal region of the experimental group. Histological examination showed that a single layer of newly formed neoplastic bone was noted on the cortical bone surface across all sites. The proximal portion displayed a bone marrow cavity at the center, encircled by a thick bone cortex with a layered structure. New bone formation was notable between existing cortical bone and the periosteum, particularly at both ends of the DFD. The use of PET in PEO was a viable option for achieving ideal bone morphology. [ABSTRACT FROM AUTHOR]

Despite the extensive use of recycled polyethylene terephthalate (rPET) in food contact materials (FCMs), research on the presence of heavy metals (HMs) and rare earth elements (REEs) during various recycling stages (e.g., flakes, granules, and preforms) remains limited. This study aimed to address these gaps by validating a rapid and sensitive analytical method to quantify 26 HMs and 4 REEs in PET and rPET matrices. An ICP-MS method was validated per EURACHEM guidelines, assessing linearity, limits of detection (LOD), limits of quantification (LOQ), accuracy, and repeatability. The method was employed for initial screening of HMs and REEs classified as non-intentionally added substances (NIASs) in PET and rPET samples. The findings showed high accuracy and reliability, with recovery rates between 80% and 120%. Analysis revealed varying concentrations of HMs and REEs, with the highest levels in 100% rPET preforms, notably Zn, Cu, and Al among HMs, and La among REEs. The study identified critical contamination points during the recycling process, highlighting the need for targeted interventions. This research provides a crucial analytical framework for assessing HMs and REEs in PET and rPET, ensuring FCM safety compliance and supporting efforts to enhance rPET product safety, promoting public health protection and advancing the circular economy. [ABSTRACT FROM AUTHOR]

The simultaneous occurrence of various pollutants in the aquatic environment raises questions about their mutual interactions. There is a gap in research on the sorption of polar substances on microplastics. This study aimed to assess the adsorption of the antidepressants sertraline, fluoxetine and duloxetine on microplastic polystyrene, polyethylene terephthalate and polyvinyl chloride, each in two versions: virgin and aged. To assess the affinity of the tested drugs for plastic and planktonic organisms, the experiment was conducted in microplastic suspensions and in a mixture of microplastics with the protozoan Spirostomum ambiguum. The Fourier transform infrared technique assessed the identity of microplastics and changes during ageing. No significant differences were found between the sorption of the tested drugs on virgin and aged microplastics. The sorption of sertraline onto microplastics was 1.5–3 times lower in the presence of the protozoa than in samples with microplastics alone. Moreover, its concentration in the protozoan cells was 10–30 times higher than in the microplastics. Considering that the amount of plankton in freshwaters is much greater than that of microplastics, it should be concluded that microplastics have a negligible share in the transport of antidepressants in surface waters. [ABSTRACT FROM AUTHOR]

As an emerging contaminant, the spatial distribution characteristics of microplastics in source water reservoirs warrant further attention from researchers. In this study, the Luhun Reservoir, which is situated in the middle reaches of the Yellow River, was selected as the object. Field sampling and detection were conducted to ascertain the presence of microplastics in water and sediment. The results indicated that the abundance of microplastics in the water varied from 1.60 to 13.26 items/L, while in the sediment it ranged from 792.38 to 2352.00 items/kg. Polyethylene, polyethylene terephthalate, and polyamides exhibited higher levels in the water, whereas polyamides and polyethylene were more predominant in the sediments. Additionally, the surface layer exhibited the highest abundance of microplastics, followed by the bottom, while the intermediate layer displayed the lowest. As the depth increased, there was a gradual decrease in the proportion of polyethylene and an increase in the proportions of polyethylene terephthalate and polyamides. The risk assessment results showed that the Pollution Risk Index value of the water was 201.79, while the sediment had a value of 184.98, indicating a moderate potential ecological risk. This study provides valuable insights into the spatial distribution patterns of microplastics at different water depths and provides crucial data support for understanding the migration patterns of microplastics in source water reservoirs. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are pervasive contaminants across all environmental compartments, with the atmosphere garnering significant attention in recent years due to its role as a crucial receptor and transporter of numerous pollutants. Deposition of these particles can occur via dry or humid processes, and their presence has been documented in areas far removed from urban and industrial centers, suggesting long-distance transport of MPs. Much of this transport is facilitated by air masses, which move in tandem with prevailing winds; however, pollinating insects, notably bees, also contribute to this dissemination as they encounter these particles during flight and foraging activities. Thus, the present study aimed to implement an established protocol for MP analysis in bees of the species Apis mellifera, given the limited research in this area within Brazil, and to ascertain whether a contamination gradient exists across three sampling sites (urban, periurban, and rural areas). A total of 505 particles were discovered across the three areas, comprising 307 fibers, 137 fragments, and sixty-one filaments. The PCA analysis indicated that the bees of the four hives located in the urban area and the bees of the two hives located in the peri-urban area had a higher amount of internal microplastic particles. Through the chemical analysis of the particles, 30 spectra were obtained, 13 polyethylene terephthalate (PET), 11 polyamide (PA), 4 polyethylene (PE), 1 polyester (PL) and 1 polyvinyl chloride (PVC) were identified. [ABSTRACT FROM AUTHOR]

In this paper, the aim is to discuss the applicability of polyethylene terephthalate fiber-reinforced polymer (PET FRP) in DSTC structures. PET FRP can improve the strength and stability of structures by providing constraints for concrete. Herein, experimental and response surface analyses of the axial compressive properties of PET FRP–concrete–steel double-skin tubular stub columns (DSTCs) based on 26 DSTC specimens subjected to axial compression testing are presented. The height of each DSTC specimen is 600 mm, the outer diameter is between 305 and 315 mm, and the thickness of the added concrete is 43 mm. The main parameters are the number of layers on the PET FRP, the compressive strength of the concrete, and the thicknesses of the steel tubes. The experimental results show that the ultimate load and ultimate axial strain can be significantly increased by increasing the number of PET FRP layers, reaching 27.34% and 28.79%, respectively. When the compressive strength of the concrete increases from C30 to C40, the ultimate load and ultimate axial strain values of the DSTCs increase by 12.54% and 8.99%, respectively. In addition, as the thickness of the steel tube increases from 6 to 8 mm, the ultimate load and ultimate axial strain increase by 34.95% and 118.90%, respectively. These results indicate that the introduction of PET FRP significantly improves the overall performance of DSTCs. Increasing the number of PET FRP layers helps to limit the circumferential strain of DSTCs. P6-S8-C40 has the best ultimate load-bearing capacity and ultimate axial strain capacity, which reach 3356.18 kN and 0.1992, respectively. The main purpose of this paper is to study the influences of the PET FRP thickness (in different layers), steel tube thickness, and concrete strength on the properties, damage mode and damage process of DSTCs. [ABSTRACT FROM AUTHOR]

Plastic waste in marine waters will undergo a degradation process that breaks down large plastic pieces into smaller particles called microplastics. The abundance of microplastics, caused by their small size (<5mm) can be easily indirectly consumed by aquatic animals. Anadara granosa is one of the bivalves that is quite vulnerable to microplastic contamination because it has the nature of a filter feeder which means it can sift particles and organic matter around it. The purpose of this study was to determine the characteristics, abundance, and types of microplastic polymers in blood clams (A. granosa). The results of microplastic observations made on 60 blood clams were 153 microplastic particles identified from 47 individuals (78%) of contaminated blood clams with an average microplastic abundance of 0.591 ± 0.083 item/gr. Fiber-type microplastics are the most dominant form found and blue is the most dominant color found in the sample. Based on the average abundance of microplastics in Anadara granosa in the coastal area of Palopo City, it is lower than several studies that have been conducted previously. Fourier Transform-Infra Red was conducted to determine the type of polymer in microplastics. Three types of polymers were found in the Anadara granosa samples polyethylene terephthalate (PET), polystyrene, and polyester. The three types of polymers have effects on human health such as respiratory problems, skin irritation, and genotoxicity. Action is needed to prevent microplastic pollution in Palopo City's rivers before microplastic pollution becomes more severe in the future. [ABSTRACT FROM AUTHOR]

It is a vital route to develop new fiber products with various physical‐mechanical properties by which their aggregation structure can be changed via controlling the spinning process parameters. In this study, five groups fiber samples had been obtained by changing the spinneret drawing ratio, two stages drawing ratio and two stages heat‐setting rate. The aggregation structure of the poly(ethylene terephthalate) (PET) industrial fibers from different spinning process was analyzed by combination use of thermal analysis, two‐dimensional wide‐angle X‐ray diffraction (WAXD), small‐angle X‐ray scattering (SAXS), and Infrared Spectroscopy (IR) measurements. It was found that, increasing the spinneret drawing ratio and two stages drawing ratio promoted the orientation and crystallinity within a certain range. For the subsequent two stages heat‐setting process, the disorientation of the amorphous chain is simulated by reducing the relaxation rate and heat setting temperature. Finally, a concise three‐dimensional structure model was established to explain the relationship between aggregation structure and property. These results have important reference for the structure and property analysis of polyester industrial fiber. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) and polylactic acid (PLA) are among the polymers used in the food industry. In this study, crude extracts of Dunaliella salina were used to treat the surface of 3D printed materials studied, aiming to provide them with an anti-adhesive property against Pseudomonas aeruginosa. The hydrophobicity of treated and untreated surfaces was characterized using the contact angle method. Furthermore, the adhesive behavior of P. aeruginosa toward the substrata surfaces was also studied theoretically and experimentally. The results showed that the untreated PLA was hydrophobic, while the untreated PET was hydrophilic. It was also found that the treated materials became hydrophilic and electron-donating. The total energy of adhesion revealed that P. aeruginosa adhesion was theoretically favorable on untreated materials, while it was unfavorable on treated ones. Moreover, the experimental data proved that the adhesion to untreated substrata was obtained, while there was complete inhibition of adhesion to treated surfaces. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENG), which efficiently capture and convert mechanical energy, offer an innovative solution for developing green energy sources. In this work, we developed a zinc oxide (ZnO)-based TENG for use in vertical contact-separation mode by combining it with several polymers (polytetrafluoroethylene [PTFE], fluorinated ethylene propylene [FEP], polydimethylsiloxane [PDMS], polyethylene terephthalate [PET], polyethylene naphthalate [PEN], polyvinylidene difluoride [PVDF]) and mica. Radio-frequency (RF) magnetron sputtering was used to fabricate ZnO thin films with higher optical transmission and c-axis orientation. When combined with mica and PEN, ZnO behaves as a negative tribo layer, while when combined with the other polymers, it behaves as a positive tribo layer. ZnO with PVDF nanofibers generated maximum output, with an open-circuit voltage of 42 V. To determine the maximum power density and energy storage performance, the ZnO-PVDF TENG response was examined under various load conditions of resistance and capacitance. The power density was calculated using this device and found to be 62 µW/cm2. Furthermore, the manufactured TENG was demonstrated to power a digital watch and LEDs. [ABSTRACT FROM AUTHOR]

Electromechanical metal oxides, such as piezoceramics, are often incompatible with soft polymers due to their crystallinity requirements, leading to high processing temperatures. This study explores the potential of ceria-based thin films as electromechanical actuators for flexible electronics. Oxygen-deficient fluorites, like cerium oxide, are centrosymmetric nonpiezoelectric crystalline metal oxides that demonstrate giant electrostriction. These films, deposited at low temperatures, integrate seamlessly with various soft substrates like polyimide and PET. Ceria thin films exhibit remarkable electrostriction (M33 > 10-16 m² V-2) and inverse pseudo-piezo coefficients (e33 > 500 pmV-1), enabling large displacements in soft electromechanical systems. Our study explores resonant and off-resonant configurations in the low-frequency regime (<1 kHz), demonstrating versatility for three-dimensional and transparent electronics. This work advances the understanding of oxygen-defective metal oxide electromechanical properties and paves the way for developing versatile and efficient electromechanical systems for applications in biomedical devices, optical devices, and beyond. [ABSTRACT FROM AUTHOR]

Plastic pollution poses a significant threat to the environment and human health on a global level. This study aimed to investigate plastic pollution in the Harari region of Ethiopia. The result indicated that 62% of respondents demonstrated good knowledge about plastic waste, and 59% of them perceived plastic waste as harmful. Polyethylene terephthalate, high-density polyethylene, polyvinyl chloride, low-density polyethylene, polypropylene, polystyrene, and polycarbonates were the types of plastic waste identified. Being female (AOR = 1.82), aged 15–45 (AOR = 1.82), married (AOR = 1.83), and having families >3 (AOR = 2.15) were significantly positively associated with good plastic waste management practice. Being illiterate (AOR = 0.52), and having poor knowledge about plastic waste (AOR = 0.54) were significantly negatively associated with poor management practice. The findings indicated that the Harari region is prone to adverse health and environmental effects from plastic pollution. Policies restricting plastic use, training municipal waste collectors and health extension workers, and improving public awareness are indispensable. [ABSTRACT FROM AUTHOR]

Although Li metal batteries (LMBs) with high flexibility are attractive energy storage systems for wearable devices due to their high energy density, there exist critical challenges such as limited loading density, poor dimensional stability, and thus mechanical instability under repeated mechanical deformations including bending, twisting, and folding. In this work, extremely flexible nano/microfiber composite electrodes are developed for LMBs. The highly flexible and mechanically durable electrode is composed of oxidized polyethylene terephthalate (O‐PET) microfiber (MF) substrates covered by single‐walled carbon nanotube (CNT) nanofibers (NF), prepared by mass‐producible O2 plasma treatment and spray‐coating. CNT nanofibers provided an electrical intertangled network to integrate the active materials (i.e., either NCM or passivated Li powder (PLP)) and anchored to a flexible O‐PET MF substrate, which permits high mass loading of active materials, improved electrochemical performance while maintaining mechanical durability. Resultantly, the flexible LMBs based on nano/micro fibrous electrodes have excellent energy density (300.1 Wh kg−1 electrode; nominal voltage of 3.7 V) and stable capacity retention (97.1%) without mechanical failure over 500 folding cycles. [ABSTRACT FROM AUTHOR]

Solar energy is the most promising source for generating residential, commercial, and industrial electricity. However, solar panels should be eco-friendly to increase sustainability during manufacturing and recycling. This study investigates the potential of using natural fibre composites as eco-friendly alternatives to conventional polyethylene terephthalate (PET) back sheets in solar panels. Furthermore, it examines the performance of sisal fibres coated with zeolite-polyester resin. The chemical composition, structural integrity, and crystalline properties of the composites were evaluated through extensive microstructural analysis. The results from the experimental analysis revealed significant improvements in voltage (8%) and current (6%) for the coated sisal fibre panels compared to conventional panels. Power output increased by 12%, and overall efficiency improved from 9.75 to 10.8%. Solar panels with sisal fibre sheets exhibit adequate tensile strength and impact resistance and reduce operating temperature by 2–3 °C, ensuring stable operation and minimizing heat loss. Statistical analysis confirmed the reliability and significance of these results. The life cycle analysis demonstrated a 60% reduction in CO2 emissions and a 50% decrease in energy consumption during the production, utilization and disposal of sisal fibre sheets. These findings underscore the viability of natural fibre composites in enhancing the performance and sustainability of solar panels. [ABSTRACT FROM AUTHOR]

To study the effect of the finishing process on the mechanical properties of polybutylene terephthalate/polyethylene terephthalate (PBT/PET) bicomponent polyester fiber, PBT/PET yarns were subjected to heat-moisture and dry-heat treatment at different temperatures and times. The tensile properties, elastic recovery, stress relaxation, and creep properties of the yarn were tested. The crystalline structure of PBT/PET fiber before and after heat treatment was studied by X-ray diffraction (XRD) to explain the change in yarn mechanical properties. The mechanical model of PBT/PET yarn was established, and the change in mechanical properties was investigated theoretically. The results show that the strength of PBT/PET yarn decreases by 10.77%, and the elongation increase by 34.81% after dry-hear treatment at 160°C for 25 min. The mechanical properties of the yarn are affected by the temperature and time of heat treatment. XRD analysis shows that the crystallinity of PBT/PET yarn decreases with the increase of heat treatment temperature and time, which may be the reason for the change in mechanical properties of PBT/PET yarn. In addition, the established model can fairly well explain the viscoelasticity of PBT/PET yarn. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures deteriorate due to changes in temperature, corrosion, and attacks of sulfate and chloride contents. Retrofitting techniques like fiber‐reinforced polymer (FRP) jacketing, known for their strength and corrosion resistance, are increasingly used to strengthen and retrofit deteriorated structural elements. Large rupture strain (LRS)‐FRP composite, composed of polyethylene terephthalate and polyethylene naphthalate, both of which have high tensile strength and high strain at rupture have been used in the studies of many researchers. This research aims to develop a reliable and accurate machine learning (ML) model to estimate the compressive strength of LRS‐FRP confined specimens. A total of 303 LRS‐FRP confined specimens were gathered after a thorough literature review to develop ML models, utilizing the linear regression, support vector regression, regression tree, and artificial neural network (ANN) algorithms. Additionally, 44 analytical models (AMs) were used to compare the performance of the developed ML models. The results revealed that the performance of the developed ANN model was higher among all the ML and AMs. The R‐value and the mean absolute percentage error (MAPE) value of the developed ANN model were 0.9822 and 6.17%, respectively. The sensitivity analysis results show that the height of the specimens had the highest impact followed by the diameter of the specimen, the number of FRP layers and thickness, and then the tensile strength of LRS‐FRP. The ANN‐based mathematical expression is simple and easy to use to predict the compressive strength of the LRS‐FRP strengthened specimens. [ABSTRACT FROM AUTHOR]

Microplastics are one of the concerning environmental pollutants because of their ubiquity. Their capability to adsorb other environmental pollutants increases the risk even further. Existing identification approaches for microplastic characterization for polymer class and their surface-adsorbed heavy metal detection require the utilization of multiple resources and expertise. The article discusses the applicability of a custom-made hyphenated Laser Induced Breakdown Spectroscopy (LIBS)—Raman spectroscopic system in characterizing microplastics by comparing the analytical performance with conventional methods such as Attenuated Total Reflectance- Fourier Transform Infrared (ATR-FTIR) spectroscopy, confocal Raman spectroscopy, and Scanning Electron Microscopy–Energy Dispersive X-ray Spectroscopy (SEM–EDS). Raman analysis identified polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) plastics, which is confirmed by confocal Raman and FTIR study of the same. LIBS study of microplastics detected heavy metals such as Al, Ni, Co, and Zn, along with Ca and Mg trace elements. The cross-examination with EDS validates these trace elements' presence on the microplastics' surface. The results of the reported LIBS-Raman analysis and its validity evaluated using conventional gold-standard methods show the applicability of the proposed methodology in characterizing microplastics from environmental resources with less or no sample preparation in short time. [ABSTRACT FROM AUTHOR]

Microplastic (MP) load in urban sewage sludge could vary annually in wastewater treatment plants (WWTPs) depending on seasonal precipitation and human activities. We investigated the seasonal dynamics in abundance and characterization of MP loading in WWTPs located in two cities across River Ganga, India's ecologically sensitive upper stretch. During a 12-month seasonal sampling (pre-monsoon, monsoon, and post-monsoon), sludge samples (n = 36) (primary sludge, PS; drying bed sludge, DBS) were collected and analyzed for load, polymer types, shape, colour, and size (20–1000 µm). Across the three seasons, MP concentrations (particles/kg) were found to be in the ranges of 93.4 ± 5.0 × 103–189.4 ± 11 × 103 in the PS and 39.6 ± 4.0 × 103–152.0 ± 7 × 103 in the DBS. The trend of MP loading was in the following order: monsoon > post-monsoon > pre-monsoon. The dominant MP size was 50–200 µm (36.22%) followed by 20–50 µm (27.65%), 200–500 µm (24.55%) and 500–1000 µm (11.58%). ATR-FTIR results revealed polypropylene, polyethylene terephthalate, polyvinyl chloride, and nylon dominating MP in sludge. This study highlights the importance of long-term monitoring of MP loading in sewage sludge to offer a more accurate estimate of MP contamination in sludge from WWTPs and develop a possible mechanism for its elimination to safeguard the environment. [ABSTRACT FROM AUTHOR]

Progress is made in the advancement of efficient and durable electrocatalysts for the ethylene glycol oxidation reaction (EGOR), which is a critical breakthrough in the conversion of waste plastic into high‐value‐added chemicals. Here, an organic ligand‐modified PdNi bimetallenes (PdNi O‐BMs) catalyst is designed and constructed through the one‐pot method. Benefiting from the frizzy and porous surface structure and inorganic–organic hybrid interface modification, PdNi O‐BMs undergo electrocatalytic reforming of ethylene glycol (EG) derived from polyethylene terephthalate (PET) to form formic acid. The unique structural advantages result in high EGOR performance. Meanwhile, the influence of Ni and organic ligand on the catalyst performance is confirmed through density functional theory calculations. This study reveals an advanced strategy for the synthesis of inorganic–organic hybrid bimetallenes, providing a green and sustainable new approach for PET value‐added transformation. [ABSTRACT FROM AUTHOR]

Fish are excellent bioindicators and can reveal the presence of plastic in the environment. Diagnosing the composition and abundance of polymers in the fish diet makes it possible to evaluate their point sources and possible trophic transfers. We aimed to use the gastrointestinal contents of Poecilia reticulata in subtropical urban streams to detect the occurrence, shape, color, size, and chemical composition of polymers. For this, the diet of 240 individuals was analyzed using the volumetric method, and the microplastics (MPs; < 5 mm) recorded were characterized using Raman spectroscopy. Individuals predominantly consumed organic detritus and aquatic macroinvertebrates, with higher proportions of Diptera. A total of 111 plastic particles (< 0.5 to 12 mm) were recorded, and a subset of 14.4% was subjected to a micro-Raman spectrometer (830 nm excitation). The occurrence of polyethylene terephthalate (PET) and polypropylene (PP) with phthalocyanine dye was recorded. Some fragments could not be identified by Raman, but they contained indigo blue dye. Poecilia reticulata had a predominantly detritivorous diet with a record of plastic consumption, reflecting environmental pollution. Our results demonstrate that individuals of P. reticulata have ingested MPs in urban streams. This reinforces the need for future studies on the relationship between the presence of MPs in fish and the level of pollution in streams, comparisons with species of different feeding habits, and the potentially harmful effects on the entire biota. [ABSTRACT FROM AUTHOR]