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Understanding core level shifts in aromatic compounds is crucial for the correct interpretation of x-ray photoelectron spectroscopy (XPS) of polycyclic aromatic hydrocarbons (PAHs), including acenes, as well as of styrenic polymers, which are increasingly relevant for the microelectronic industry, among other applications. The effect of delocalization through π aromatic systems on the stabilization of valence molecular orbitals has been widely investigated in the past. However, little has been reported on the impact on the deeper C1s core energy levels. In this work, we use first-principles calculations at the level of many body perturbation theory to compute the C1s binding energies of several aromatic systems. We report a C1s red shift in PAHs and acenes of increasing size, both in the gas phase and in the molecular crystal. C1s red shifts are also calculated for stacked benzene and naphthalene pairs at decreasing intermolecular distances. A C1s red shift is in addition found between oligomers of poly(p-hydroxystyrene) and polystyrene of increasing length, which we attribute to ring–ring interactions between the side-chains. The predicted shifts are larger than common instrumental errors and could, therefore, be detected in XPS experiments. [ABSTRACT FROM AUTHOR]

Diblock copolymers consisting of higher hydrophobic styrene and hydrophilic N-hydroxyethylacrylamide (HEAAm) segments were successfully synthesized via direct two-step atom transfer radical polymerization. Polystyrene (PS) homopolymers were synthesized using methyl 4-(bromo-methyl) benzoate initiator in N,N′- dimethylformamide (DMF) in the presence of Cu(I)Br/pentamethyldiethylene tetramine (PMDETA) catalyst system at 90 and 110 °C in nitrogen atmosphere. PS was used as macro-initiator for the synthesis of PS-b-PHEAAm polymer. Block copolymerizations were carried out in pure DMF in the presence of the same catalyst system at 110 °C while argon was used for deoxygenation and inert environment. Block copolymer was purified through dialysis into deionized water using a dialysis tubing (MWCO 3500, cellulose membrane). The number average molecular weight of PS polymers (Mn = 2240, 3250 and 10,800 Da) was determined by size exclusion chromatography using tetrahydrofuran (THF) as eluent. The chemical structures, functional groups and actual compositions of copolymer were determined using instrumental data, c.f. elemental analysis, attenuated total reflectance infra-red and proton—nuclear magnetic resonance (1H-NMR) spectroscopy analysis. Thermo-gravimetric analysis confirms that diblock copolymer has higher thermal stability than PS homopolymer. Co-solvent effect on particle formation was investigated by regulating dielectric constant. It is revealed that THF/DMF (9:1) provides susceptible environment for the formation of smallest size (13 ± 4 nm) particle. This synthetic route would establish a direct synthesis of diblock copolymer with antagonistic segments for advanced technological applications. [ABSTRACT FROM AUTHOR]

Purpose: To assess the current practices surrounding Uterine Fibroid Embolization (UFE) in Canada. Methods: An online survey was sent to Canadian Association for Interventional Radiology (CAIR) members. It included questions on symptoms prompting UFE, patient awareness, investigation, UFE settings, the number of UFE procedures, and post-UFE care. The findings were discussed at CAIR's 2023 annual meeting by an expert panel. Results: Out of 792 surveys sent, 87 were filled (11%). Menorrhagia is the most common indication for UFE (87%). Women's awareness of UFE as a treatment option for fibroids is viewed as poor or average by 94% of our survey respondents. Most respondents see patients in clinics (92%) before the procedure and evaluate fibroids with MRI pre-UFE (76%). There is variability in care post-UFE, with 33% of procedures being performed as day surgery while 67% lead to overnight stay. For pain management, intravenous analgesia (including patient-controlled analgesia) is used in 76% (63/83) of cases while 19% (16/83) of respondents mentioned using epidural analgesia. Finally, there is an even split between embolic agent used; non-spherical polyvinyl alcohol (50%) and spherical particles (50%). Conclusion: Respondents believe patients in Canada still have limited awareness of UFE. Interventional radiologists are increasingly involved in the entire patient care trajectory, overseeing pre-and post-procedure care and hospitalizing patients. For pain management after UFE, it is observed that while epidural analgesia has been demonstrated more effective than alternatives, it is not widely used as the primary method. [ABSTRACT FROM AUTHOR]

Different contributions of dopants based on Yttrium oxide (Y 2 O 3)/titanium(IV) oxide (TiO 2)/carbon nanotube (CNT)/have been incorporated into the polymeric matrix of Polystyrene (PS). These films were fabricated in films due to their feasibility and low cost. The contact angle revealed that the dopants supported the hydrophilicity of the films that Y 2 O 3 /TiO 2 /CNT/PS represents the second highest wettability with (56.15 ± 6.35°) films, while Y 2 O 3 /PS film displays rough surface with the highest wettability with (32.5 ± 0.9°). we examined the impact of Y 2 O 3 /TiO 2 /CNT/PS composite on the viability of a human lung cell-line to better understand its biological behavior. Specifically, we measured cell viability as a means to assess the effect of the composite. The results revealed that at a concentration of 5000 μg/ml, the cell viability was measured to be 31.8 %. However, at a lower concentration of 2.4 μg/ml, the cell viability increased significantly to 117.9 %. These findings highlight a concentration-dependent relationship between the composite and the viability of the human lung cell-line. The observed cell viability exceeding 100 % indicates that the Y 2 O 3 /TiO 2 /CNT/PS composite scaffold had a positive effect on cell proliferation and generation. This suggests that the modified PS scaffold is conducive to cellular growth and can be considered safe for human use. The results imply that the composite scaffold promotes a favorable cellular environment, potentially supporting tissue regeneration and indicating its potential suitability for biomedical applications. The surface morphology shows that the topography of the films was changed clearly with the dopants of Yttrium oxide, titanium(IV) oxide and CNT components. The TiO 2 granules implanted in the PS composition cause an increase in pore size to an average of 2.2 μm. Pore diameters ranging from 100 to 500 μm may enhance cell proliferation, while lower sizes lead to more stable implantable discs. [ABSTRACT FROM AUTHOR]

The current study aims to model and optimize the catalytic pyrolysis of plastics, incorporating an agricultural biomass waste-derived catalyst. Polystyrene (PSW) and polypropylene (PPW) are experimented with thermal and catalytic pyrolysis. Agricultural biomass waste (wheat husk) was selected and acid treated with sulfuric acid (HZSM-5SA) and hydrochloric acid (HZSM-5CA), and then used as catalyst. Thermal and catalytic pyrolysis were conducted in a semi batch reactor, with reaction temperature (500 ℃) and different ratios (10:1, 10:2 & 10:3). At a ratio 10:2, PSW with HZSM-5SA produced 91.19 wt.% of oil yield and PPW with HZSM-5SA produced 85.73 wt.% of oil yield. The catalyst HZSM-5SA was effective in the reduction of reaction temperature and time, it decreased from 450 ℃ to 437 ℃ and 22 min to 14 min for PSW. Catalyst activity was also observed for PPW, the reaction temperature decreased from 471 ℃ to 456 ℃ and 34 min to 19 min. Oil properties were determined and it was found that the kinematic viscosity of oil obtained from PSW with HZSM-5SA was 2.53 cSt, which coincide with the diesel Bharat Stage (BS VI 2020). Total conversion of pyrolysis products was predicted using six Machine Learning (ML) models such as Random Forest, Support Vector, K-Nearest Neighbor, Decision Tree, AdaBoost, and Gradient Boost. Among all the models, the Gradient Boost regressor model had a good evaluation metrics of R2 value of 0.984 and RMSE of 0.019, respectively. This study illustrates the use of ML models to predict the total conversion and their correlation matrix with target and feature variables. This study also highlights that cost-effective catalyst can be prepared from biomass (wheat husk) and the use of ML models to train the datasets and evaluate the actual and predicted values. Highlights: In situ catalytic pyrolysis of PSW and PPW was experimented. HZSM-5 prepared from agricultural biomass waste (wheat husk). Enhanced liquid yield of 91.19 wt.% obtained for PSW + HZSM-5SA. 70.19 wt.% of diesel-like fractions obtained in oil yield. Machine Learning model—Gradient Boost algorithm predicted the total conversion of products with R2 0.984. [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]

Although the introduction of plastics has improved humanity's everyday life, the fast accumulation of plastic waste, including microplastics and nanoplastics, have created numerous problems with recent studies highlighting their involvement in various aspects of our lives. Upcycling of plastics, the conversion of plastic waste to high‐added value chemicals, is a way to combat plastic waste that is receiving increased attention. Herein, we describe a novel aerobic photochemical process for the upcycling of real‐life polystyrene‐based plastics into benzoic acid. A new process employing a thioxanthone‐derivative, in combination with N‐bromosuccinimide, under ambient air and 390 nm irradiation is capable of upcycling real‐life polystyrene‐derived products in benzoic acid in yields varying from 24–54 %. [ABSTRACT FROM AUTHOR]

BACKGROUND: Plastic as a durable, inexpensive, easy to manufacture organic synthetic polymer materials are widely used. At the same time, plastic resistance to high temperatures, acid and alkali resistance, corrosion-resistant properties make it difficult to degrade in nature, and ultimately forming a huge number of microplastic pollution threatening human health. OBJECTIVE: To investigate the effects of microplastic exposure on growth and development and hepatic lipid metabolism in mice. METHODS: Twenty C57BL/6J male mice were adaptively fed for one week, and then randomly divided into normal and microplastic groups (n=10 per group). Mice in the normal group were given a normal diet and water, for 4 weeks. Mice in the microplastic group were given a normal diet and free drinking of microplastic (polystyrene) water with a concentration of 1 000 μg/L, for 4 weeks. At 2 and 4 weeks of drinking, body mass and grip strength, blood lipids and liver and kidney function, ultrasonic morphology and pathological morphology of liver and lipid deposition were detected. RESULTS AND CONCLUSION: (1) With the extension of time, the body mass of mice in the two groups gradually increased, and the body mass of mice in the microplastic group was greater than that in the normal group after 2, 4 weeks of drinking water (P < 0.05). With the extension of time, the grip strength of mice in the normal group gradually increased, and the grip strength of mice in the microplastic group first decreased and then increased, and the grip strength of mice in the microplastic group was lower than that in the normal group after drinking water for 4 weeks (P < 0.05). (2) Liver ultrasound examination showed that compared with the normal group, the ultrasonic echo signal of the liver in the microplastic group was enhanced after 2 and 4 weeks of drinking water. (3) Hematoxylin-eosin staining showed that the morphology of liver cells in the microplastic group did not change significantly after 2 and 4 weeks of drinking water, but inflammatory cell infiltration could be seen. Oil red O staining showed that obvious lipid deposition was observed in the liver of microplastic group after 2 and 4 weeks of drinking water. (4) Compared with the normal group, the levels of serum high density lipoprotein cholesterol, triacylglycerol, and aspartate aminotransferase in the microplastic group were decreased after 2 weeks of drinking water (P < 0.05), and the serum triacylglycerol concentration was decreased after 4 weeks of drinking water (P < 0.05). (5) These findings confirm that microplastics may cause weight gain, loss of physical strength, and abnormal hepatic lipid metabolism in mice. [ABSTRACT FROM AUTHOR]

Environment plastic accumulation has been attracting the attention of both political and scientific communities, who wish to reduce global pollution. Plastic items have been detected everywhere, from oceans to the air, raising concerns about the fate of plastics within organisms. Leaked plastics are ingested by animals, entering the food chain and eventually reaching humans. Although a lot of studies focused on the evaluation of plastic particles in the environment and living organisms have already been published, the behavior of plastic at the cellular level is still missing. Here, we analyzed the bioaccumulation and extrusion trend of two differently sized plastic particles (1 and 2 µm), testing them on three human epithelial cell lines (liver, lung, and gut) that represent epithelial sites mainly exposed to plastic. A different behavior was detected, and the major plastic uptake was shown by liver cells, where the 1 µm beads accumulated with a dose-dependent profile. Moreover, a 60% reduction in the content of 1 µm particles in cells was evaluated after plastic removal. Finally, the viability and proliferation of the three human cell lines were not significantly affected by both the 1 and 2 µm beads, suggesting that cells might have a defense mechanism against plastic exposure risk. [ABSTRACT FROM AUTHOR]

Polymer cubosomes (PCs) are a recent class of self‐assembled nanostructures with great application potential due to their high porosity and surface area. Currently, most reported PCs consist of polystyrene block copolymers (BCPs), for which self‐assembly parameters are rather well understood. Changing the block chemistry would be desirable to introduce more functionality; however, knowledge of adapting the self‐assembly process to new chemistries remains limited. This work, reports on synthesizing poly(ethylene oxide)‐block‐poly(4‐acetoxystyrene) and its copolymers with styrene, and provide conditions for their self‐assembly into PCs with high yield and high inner order. It is shown that the polarity of the starting solvent toward the corona block allows tuning of the final morphology by controlling the corona volume and packing parameter. [ABSTRACT FROM AUTHOR]

Microplastics, particularly those in the micrometer scale, have been shown to enter the human body through ingestion, inhalation, and dermal contact. Recent research indicates that microplastics can potentially impact the central nervous system (CNS) by crossing the blood-brain barrier (BBB). However, the exact mechanisms of their transport, uptake, and subsequent toxicity at BBB remain unclear. In this study, we evaluated the size-dependent uptake and cytotoxicity of polystyrene microparticles using an engineered BBB model. Our findings demonstrate that 0.2 μm polystyrene microparticles exhibit significantly higher uptake and transendothelial transport compared to 1.0 μm polystyrene microparticles, leading to increased permeability and cellular damage. After 24 h of exposure, permeability increased by 15.6-fold for the 0.2 μm particles and 2-fold for the 1.0 μm particles compared to the control. After 72 h of exposure, permeability further increased by 27.3-fold for the 0.2 μm particles and a 4.5-fold for the 1.0 μm particles compared to the control. Notably, microplastics administration following TNF-α treatment resulted in enhanced absorption and greater BBB damage compared to non-stimulated conditions. Additionally, the size-dependent toxicity observed differently between 2D cultured cells and 3D BBB models, highlighting the importance of testing models in evaluating environmental toxicity. [ABSTRACT FROM AUTHOR]

Polystyrene/polytetrafluoroethylene (PS/PTFE) in‐situ fibrillated nanocomposites were prepared by melt blending using a HAAKE torque rheometer, and the effects of different contents of in‐situ nanofibrillated PTFE on the properties of PS/PTFE nanocomposites were studied. The results showed that PTFE was in‐situ nanofibrillation in the composites, and the toughness, energy storage modulus and complex viscosity of PS/PTFE nanocomposite are all improved. When the content of PTFE was 3 wt%, the elongation at break was the highest, which was three times that of neat PS. What is more, the addition of PTFE significantly improved the cell morphology of PS/PTFE nanocomposite foams by supercritical fluid foaming. The cell structure and morphology of PS/PTFE (3 wt%) nanocomposite foam was the best under 110°C foaming temperature, and the cell diameter and cell density were 3.27 μm and 1.11 × 1010 cells/cm3, respectively. In addition, the tensile strength of PS/PTFE nanocomposite foams increased from 35.4 MPa of neat PS foam to 39.6 MPa of PS/PTFE (3 wt%) foam. [ABSTRACT FROM AUTHOR]

Polystyrene (PS), a polymer material renowned for its notable optical and mechanical properties, as well as low cost and ease of processing, stands as one of optimal candidate for flexible electrode substrate materials. However, prevalent modification techniques such as lithography, electron beam evaporation, and plasma etching all entail the requirement for specialized equipment and precise operation, thereby significantly elevating the technical barrier. In this study, we introduce a chemical plating method to fabricate a gold film electrode, coupled with prussian blue (PB) and glucose oxidase (GOx), for the development of a glucose electrochemical biosensor. This process offers simplicity, cost‐effectiveness, and feasibility under regular experimental conditions. The electrode surface is covered with numerous gold nanoparticles, effectively augmenting the actual electrode area and enhancing electron transfer efficiency. Remarkably, without the addition of sensitizing agents, the biosensor achieves highly sensitive glucose detection. The proposed biosensor exhibits a broad linear relationship in the concentration range of 0.005–1 mM, with a detection limit of 4.4 μM. Moreover, it exhibits favorable performance in detecting glucose levels in sweat samples, showcasing promising prospects for personal healthcare diagnostics. [ABSTRACT FROM AUTHOR]

The adsorption of Cs(I), Sr(II) and Y(III) from aqueous solutions using silica polystyrene (SPS) impregnated with Aliquat-336 (A-336) and Theonyl triflouroacetone (HTTA) was investigated. The synthesized materials; SPS, A-336@SPS and HTTA@SPS were characterized using FTIR, XRD and SEM. The order of adsorption capacity is Cs(I)>Sr(II)>Y(III). The adsorption capacity (qe) for Cs(I), Sr(II) and Y(III) was found to be 2.3, 0.75 and 0.55 mg/g, respectively. The maximum separation factor of SF(Cs/Sr), SF(Cs/Y) and SF(Sr/Y) was 16.01, 29.32, and 1.83, respectively. The selective adsorption of Cs(I) by A-336@SPS is attributed to the formation of strong complex between nitrogen atom of A-336@SPS and Cs(I). [ABSTRACT FROM AUTHOR]

We present the results of experimental study on measuring the thermodiffusion, molecular diffusion and Soret coefficients of polystyrene (4,880 g/mol) in the pure solvents toluene and cyclohexane at 298 K and atmospheric pressure. The experiments have been carried out for a wide range of concentrations, starting from the diluted state with 2 % polystyrene mass fraction (proposed in the DCMIX4 project) up to the semidilute regime of 20 % polystyrene mass fraction. In addition, we present a complete characterisation of the thermophysical properties of the analysed mixtures. Thermodiffusion, molecular diffusion and Soret coefficients of binary polymeric samples have been measured by combining the traditional thermogravitational column technique, the thermogravitational microcolumn and the optical beam deflection method. In toluene, the obtained experimental results are consistent with literature, showing that the magnitude of the mass transport thermoproperties decrease significantly with increasing polystyrene concentration, which is a first indication of an approaching glass transition in the concentrated regime. The results for thermodiffusion and molecular diffusion coefficients in cyclohexane as a function of concentration exhibit a similar trend. Nevertheless, the Soret coefficient seems to show an opposite tendency for the two solvents, increasing in magnitude for cyclohexane, at least up to the analysed polystyrene concentration. [ABSTRACT FROM AUTHOR]

Polystyrene (PS) is a thermoplastic polymer commonly used in various applications due to its bulk properties. Designing functional polystyrenes with well-defined structures for targeted applications is of significant interest due to the rigid and apolar nature of the polymer chain. Progress is hindered to date by the limitations of current analytical methods in defining the atomistic-level folding of the polymer chain. The integration of ion mobility spectrometry and molecular dynamics simulations is beneficial in addressing these challenges. However, data on gas-phase polystyrene ions are rarely reported in the literature. We herein investigate the gas phase structure of polystyrene ions with different end groups to establish how the nature and the rigidity of the monomer unit affect the charge stabilization. We find that, in contrast to polar polymers in which the charges are located deep in the ionic globules, the charges in the PS ions are rather located at the periphery of the polymer backbone, leading to singly and doubly charged PS ions adopting dense elliptic-shaped structures. Molecular dynamics (MD) simulations indicate that the folding of the PS rigid chain is controlled by phenyl ring interactions with the charge ultimately remaining excluded from the core of the globular ions, whereas the folding of polyether ions is initiated by the folding of the flexible polyether chain around the sodium ion that remains deeply enclosed in the core of the ions. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of long-term polystyrene microplastics (PS-MPs) exposure on hepatic lipid metabolism in vivo by lipidomics. H&E staining showed long-term PS-MPs exposure could trigger the hepatic inflammatory cell infiltration and hepatic steatosis in SD rats, indicating long-term PS-MPs exposure caused hepatoxicity. Lipidomics revealed that the concentrations of 8 lipid metabolites in the liver were altered after exposure to PS-MPs for both 6 and 12 months, namely LdMePE (16:0), LPC (18:1), LPC (18:2), LPC (20:4), PC (17:0_20:4), PC (18:2_22:6), PC (22:6_13:0) and SM (d18:1_24:0), which were all statistically different from the control groups detected at both time points after PS-MPs exposure, suggesting the mainly metabolic pathway was glycerolipid metabolism. This study showed chronic exposure to PS-MPs could cause hepatotoxicity and induce hepatic lipidomics alterations in vivo , which could provide an essential clue for the safety assessment of PS-MPs. • Long-term PS-MPs exposure could disturb the lipid homeostasis in the liver. • 8 lipid metabolites were differed after exposure to PS-MPs by lipidomics analysis. • Long-term PS-MPs exposure might increase the risk of nonalcoholic fatty liver disease. [ABSTRACT FROM AUTHOR]

A new polystyrene-supported Schiff base resin, o-hydroxyacetophenonediethylenetriamine-polystyrene (PS-HAPDA), has been synthesized via a reaction between the commercially available chloromethyl polystyrene polymer and the Schiff base o-hydroxyacetophenonediethylenetriamine (HAPDA). The structure of the synthesized polymer has been determined by Fourier transform infrared spectroscopy and thermogravimetry differential thermal analysis (TG/DTA). The chelating properties of the new polymer toward some divalent metal ions were studied by a batch equilibration technique under different experimental conditions. Results revealed that the metal-ion uptake follows the order Cu+2 > Zn+2 > Ni+2 > Co+2 > Pb+2. The antibacterial activity of complexed PS-HAPDA was tested against Gram-negative strains and Gram-positive strains. [ABSTRACT FROM AUTHOR]

Polystyrene microplastics, especially those smaller than 10 μm, reduce male fertility in murine models, but whether they affect male reproduction in humans is poorly understood. Here, we studied polystyrene microplastics smaller than 10 μm in human semen samples and evaluated their toxicity to human sperm. We also tested the use of magnetic iron oxide nanoparticles to remove nanoplastics and decrease their toxicity in human sperm. Results show that human semen is contaminated by approximately 3.57 ± 0.32 μg/mL polystyrene microplastics smaller than 10 μm. Polystyrene nanoplastics of 25–100 nm penetrate and damage human sperm at semen-relevant concentrations of 5 and 50 μg of nanoplastic per mL, while 0.5–10 μm polystyrene microplastics bind to the sperm. We also found that 25-nm polystyrene nanoplastics exhibited a synergistic toxicity with bisphenol A on human sperm. Nonetheless, we observed that environmental microplastics released from disposable paper cups do not pose a significant hazard to human sperm under our conditions. Furthermore, magnetic iron oxide nanoparticles can aggregate and coprecipitate with 25-nm polystyrene nanoplastics to eliminate their adverse effects on human sperm. [ABSTRACT FROM AUTHOR]

The increasing awareness of the potential health risks associated with microplastics' (MPs) and nanoplastics' (NPs) presence in the environment has led to a significant rise in research focused on these particles over the past few years. This review focuses on the research on MPs'/NPs' presence and spread, pathways of exposure, toxicological effects on human health and legal framework related to MP/NP challenges. Several research projects have aimed to assess their potential harm to human health, focusing on different systems and organs. After exposure (independent of the pathway), these hazards reach the blood stream and concentrate in different organs. Further, they are responsible for harmful changes, having an immediate effect (pain, inflammation, or hormone imbalance) or lead to a long-term disease (e.g., infertility, chronic obstructive pulmonary disease, or cancer). Toxicological effects have been noticed at high concentrations of MPs, specifically polystyrene, the most widespread typical MP, but only short-term effects have been mostly studied. Significant quantities of consumed MPs have been discovered to have diverse detrimental effects, posing a threat to human welfare. The exact concentrations of microplastics that are inhaled and swallowed and then build up in the human body are still not known. Further investigation is necessary to evaluate the impact of MP/NP contamination at minimal concentrations and for prolonged durations. [ABSTRACT FROM AUTHOR]

Abstract—As a result of studying the mechanism of polishing with a disperse system from micro- and nanopowders for polystyrene scintillators, sludge nanoparticles (SP) and polishing powder wear particles (PP) were established to form due to Förster resonance energy transfer (FRET) occurring in a four-mode regime in the open microresonator formed by the surfaces of a treated material and a polishing powder particle. The disperse phase particles in the polishing disperse system were demonstrated to wear twice faster as compared to treated material removal. The total cross section of SPs scattering on PPs (31.1 Mb) during the scattering of quantum nanoparticles in the open resonator formed by the treated material and lap surfaces was shown to be much larger than the total cross section of PPs scattering on SPs to result in the absence of a deposit from polishing powder wear nanoparticles on the treated surface and the presence of a deposit from sludge nanoparticles on the lap surface. The results of calculating the material removal rate were established to agree with the data of experimental polystyrene polishing rate measurements at a deviation up to 4%, and SP deposit fragments on the lap surface were from 0.2 to 1.0 mm in size and discretely arranged within an annular zone with a radius of 24.5 mm. The polishing of polystyrene based scintillation elements with a disperse system from micro- and nanoparticles was shown to improve the pulse shape discrimination of fast neutrons and gamma quanta by high aspect ratio detectors by 14%. [ABSTRACT FROM AUTHOR]

Context: Microplastics (MPs), whether originating from primary or secondary means, have emerged as a significant global issue nowadays. Aims: The current research was designed to assess the toxicological consequences of polystyrene MPs (PS-MPs) on the growth, digestibility, body composition, haematology and histopathology of Cirrhinus mrigala fingerlings. Methods: In this study, six test diets with different MP concentrations were used, including a control group (0% MPs) and groups with 0.5, 1, 1.5, 2 and 2.5% MPs in sunflower meal-based diets. For a 90-day duration, 270 fingerlings (6.54 ± 0.02 g fish−1) were placed in triplicate groups in tanks, with each tank consisting of 15 fingerlings, feeding at a rate equivalent to 5% of their live wet bodyweight. Key results: The findings revealed a negative correlation between MP concentration and fingerlings performance, encompassing growth, digestibility, body composition, histopathology and hematology. Conclusions: The results indicate that 2.5% MPs inclusion in C. mrigala adversely affects growth, digestibility, body composition, histopathology and hematology. Implications: This research highlights the harmful effects of PS-MPs on C. mrigala fingerlings, emphasising urgent global action to address and mitigate aquatic ecosystem threats. Microplastics (MPs) have emerged as a significant global issue. The current study was conducted to evaluate toxicological consequences of polystyrene MPs (PS-MPs) that alter growth, carcass, nutrient digestibility, haematology and histopathology of Cirrhinus mrigala fish. After 90 days of trial, findings showed a negative corelation between MPs concentration and all parameters. (Image credit: Syed Makhdoom Hussain.) [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are a potential threat to the marine environment and its associated ecosystem functions. Earlier investigations revealed that the microbiome plays a crucial role in deciding the fate of MPs in the environment. Further studies also highlighted the influences of environment and polymer types on the plastisphere microbiome. Nevertheless, the major factor that determines the plastisphere microbiome remains elusive. Thus, we examined the publicly available marine plastisphere data generated from polyethylene (PE), polypropylene (PP), and polystyrene (PS), collected from three different locations to identify the importance of environment and/or polymer types in shaping the microbiome. The beta diversity analyses showed a clear distinction between samples collected from different locations. The PERMANOVA results illustrated a significant influence of environment and sample type (control/PE/PP/PS) on the microbial communities. However, the influence of sample type on microbial diversity was not significant (P-value > 0.05) when the control samples were removed from the dataset but the environment remained a significant factor (P-value < 0.05). Further, the differential abundance analyses explicitly showed the abundance of many bacterial taxa to be significantly influenced (adjusted P-value < 0.05) by the locations rather than the polymer types. The validation analysis also supports the findings. Thus, this study suggests that both the surrounding environment and polymer types determine the microbial communities on marine MPs, but the role of the environment in shaping the microbial composition is greater than that of polymer types. [ABSTRACT FROM AUTHOR]

The rapid accumulation of polymer waste presents a significant environmental challenge, necessitating innovative waste management and resource recovery strategies. This study investigates the potential of chemical recycling via pyrolysis of plastic waste, specifically polystyrene (PS) and polypropylene (PP), to produce high-quality pyrolytic oils (WPPOs) for use as alternative fuels. The physicochemical properties of these oils were analyzed, and their performance in a gas turbine engine was evaluated. The results show that WPPOs increase NOx emissions by 61% for PSO and 26% for PPO, while CO emissions rise by 25% for PSO. Exhaust gas temperatures increase by 12.2% for PSO and 8.7% for PPO. Thrust-specific fuel consumption (TSFC) decreases by 13.8% for PPO, with negligible changes for PSO. The environmental-economic analysis indicates that using WPPO results in a 68.2% increase in environmental impact for PS100 and 64% for PP100, with energy emission indexes rising by 101% for PS100 and 57.8% for PP100, compared to JET A. Although WPPO reduces fuel costs by 15%, it significantly elevates emissions of CO2, CO, and NOx. This research advances the understanding of integrating waste plastic pyrolysis into energy systems, promoting a circular economy while balancing environmental challenges. [ABSTRACT FROM AUTHOR]

A precautionary specific migration limit of 40 µg/kg for styrene from food contact materials is currently under evaluation in Europe. In the ongoing discussion about applicable methods to demonstrate compliance, testing with food instead of simulants or total transfer calculations has been proposed. In this study, the residual styrene levels in high-impact polystyrene (HIPS) blended with general-purpose polystyrene (GPPS) were determined at several levels of the processing chain of yoghurt pots (from pellets to sheets, then to pots). The styrene migration from extruded sheets and thermoformed pots was analyzed in food simulants at 10 days/20 °C and 40 °C, as well as in yoghurt after storage at 8 °C after 50 days. The obtained results show that the residual styrene content in the PS materials correlates with migration. However, the migration of styrene was far below the total transfer assumption. Styrene migration from the sheets into food simulants and into yoghurt exceeded that migrating from the pots. Styrene migration into food simulants in 20% ethanol at 10 days/20 °C and 40 °C and, more clearly, in 50% ethanol at 10 days/40 °C, was higher than that into yoghurt tested on the best-before date. Styrene migration from PS pots into yoghurt after storage at 8 °C for 50 days reached up to 15 µg/kg (applying the EU cube model), which would be conservatively covered by testing the PS pots with 20% ethanol at 10 days/20 °C. [ABSTRACT FROM AUTHOR]

BACKGROUND: Textile-sizing mill workers are exposed to various hazards in the sizing units during their working hours and are at risk of acquiring lung impairments due to the usage of sizing chemicals in the sizing process. OBJECTIVE: The main aim of this study is to assess the influence of cotton dust and sizing agents on lung function and breathing difficulties among Indian textile sizing mill workers. METHODS: This cross-sectional study was carried out at a textile-sizing mill from August 2022 to September 2022. A modified questionnaire based American Thoracic Society's standard was used to assess respiratory symptoms among sizing mill workers and the pulmonary function test was conducted Spirometry. The chi-square test was used to find the difference between respiratory symptoms and the t-test was used to find the difference between spirometric parameters. RESULTS: Textile sizing mill workers showed significant (P < 0.0001) decline in peak expiratory flow rate, forced vital capacity (FVC), ratio of FEV1 and forced vital capacity, and forced expiratory volume in 1 s (FEV1). There was an association between symptoms and duration of exposure to pulmonary abnormality. Sizing mill workers showed a significant decline in lung functions and an increase in pulmonary symptoms. As the service duration of exposure in terms of years increased, respiratory symptoms increased and spirometric abnormality also increased. CONCLUSION: This study confirms that sizing agents such as polyvinyl alcohol (PVA), emulsifier, wax, carboxymethyl cellulose (CMC), and starch used in sizing mills are also responsible for respiratory illness and lung impairment among textile workers. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the effective chemical treatment of fly Ash (FA) that affects the mechanical, thermal, and water absorption capabilities of polystyrene/styrene‐butadiene‐copolymer (PS/SBC) nanocomposites. NaOH, H2SO4 and distilled water have been employed to conduct the chemical treatment. Specimens have been prepared using injection molding technique. In order to evaluate the mechanical properties of the material, tensile, flexural, impact, and hardness tests were carried out. thermo‐gravimetric analysis (TGA) and differential thermal analysis (DTA) were employed to gain an understanding of the thermal behavior of the material. Furthermore, to determine the moisture resistance, water absorption experiments were conducted. Experimental results show that, alkali‐treated FA (AL‐FA) demonstrated the maximum values with an ultimate tensile strength of 26.68 MPa, acid‐treated FA (AC‐FA) composite exhibiting the highest flexural strength at 5 MPa whereas water‐treated FA (WA‐FA) composite led to better impact strength of 17.6 kJ/m2. TGA revealed that WA‐FA and AL‐FA composites experienced an 80% reduction in weight at 500°C, while AC‐FA composites exhibited weight reductions of 90%. The significance of treatment methods in interfacial interactions between the polymer and FA has been studied through morphological analysis. These findings provide valuable insights that can be applied to future research and industrial applications in the field of sustainable materials engineering. Highlights: Polystyrene/Styrene‐Butadiene‐Copolymer composites were prepared with Fly ash (FA) filler.FA pre‐treated by NaOH (AL‐FA), H2SO4 (AC‐FA) and distilled water (WA‐FA).Injection molding technique was employed to prepare the ASTM standard samples.WA‐FA composite exhibited the highest ductility but lower tensile strength.TGA revealed that AC‐FA composites exhibited weight reductions of 90%. [ABSTRACT FROM AUTHOR]

Plastic has been known as an artificial polymer whereas environmental microplastics become a global concern. Microplastics are reported to cause immunotoxicity in humans through gut deposition and entering the bloodstream. This study is a comprehensive indication of the recent research on microplastic toxicity in the gastrointestinal system. We performed bibliographic analysis using VOS viewer software and analyzed the data received on microplastics and their impact on gut health which has grown exponentially since 2016. Recent findings also support microplastic toxicity in combination with heavy metals. The smaller particle size and other factors enhanced the adsorption ability of environmental contamination such as heavy metals on microplastic which increased their bioaccumulation. Such toxic complexes of heavy metals and microplastics are a concern to natural ecosystems and environmental biologists. Few reports also demonstrated the biofilm formation on microplastic surfaces which might cause greater environmental as well as human health risks. Notably, terms of determining the microplastics in human tissues through several analytical techniques are still limited to some extent. Future research should be focused on the quantification of microplastics in human tissues, the combined effect of microplastics with other contaminants, and their effects on pre-existing diseases. This study boosts understanding of the potential impacts of microplastic and nanoplastic toxicity in the human gastrointestinal system. [ABSTRACT FROM AUTHOR]

The prime objective of the current research work was to understand the role of microwave-assisted pyrolysis for the upgradation of expanded polystyrene (EPS) waste into valuable aromatic hydrocarbons. Ethyl acetate solvent was used to dissolve the EPS to enhance the homogeneous dispersion of EPS with susceptor particles. Biochar obtained from the pyrolysis was used as a susceptor. The design of experiments method was used to understand the role of microwave power (300 W, 450 W, and 600 W) and susceptor quantity (5 g, 10 g, and 15 g) in the pyrolysis process. The pyrolysis was conducted till the temperature reached up to 600 °C, and this temperature was achieved in the time interval of 14–38 min based on the experimental conditions. The obtained average heating rates varied in the range of 15 to 41 °C/min to attain the pyrolysis temperature. The EPS feed was converted into char (~ 2.5 wt.%), oil (51 to 60 wt.%), and gaseous (37 to 47 wt.%) products. The specific microwave energy (J/g) was calculated to know the energy requirement; it increased with an increase in susceptor quantity and microwave power, whereas specific microwave power (W/g) was a function of microwave power and increased from 15 to 30 W/g. The predicted values calculated using the model equations closely matched the actual values showing that the developed model equations via optimization had a good fit. The obtained pyrolysis oil physicochemical properties including viscosity (1 to 1.4 cP), density (990 to 1030 kg/m3), heating value (39 to 42 MJ/kg), and flash point (98 to 101 °C) were thoroughly analyzed. The pyrolysis oil was rich in aromatic hydrocarbons and it was predominantly composed of styrene, cyclopropyl methylbenzene, and alkylbenzene derivates. [ABSTRACT FROM AUTHOR]

Integrated optical tweezers have the potential to enable highly-compact, low-cost, mass-manufactured, and broadly-accessible optical manipulation when compared to standard bulk-optical tweezers. However, integrated demonstrations to date have been fundamentally limited to micron-scale standoff distances and, often, passive trapping functionality, making them incompatible with many existing applications and significantly limiting their utility, especially for biological studies. In this work, we demonstrate optical trapping and tweezing using an integrated OPA for the first time, increasing the standoff distance of integrated optical tweezers by over two orders of magnitude compared to prior demonstrations. First, we demonstrate trapping of polystyrene microspheres 5 mm above the surface of the chip and calibrate the trap force. Next, we show tweezing of polystyrene microspheres in one dimension by non-mechanically steering the trap by varying the input laser wavelength. Finally, we use the OPA tweezers to demonstrate, to the best of our knowledge, the first cell experiments using single-beam integrated optical tweezers, showing controlled deformation of mouse lymphoblast cells. This work introduces a new modality for integrated optical tweezers, significantly expanding their utility and compatibility with existing applications, especially for biological experiments. The authors demonstrate optical tweezing of microparticles and cells using an integrated optical phased array for the first time, increasing the standoff distance of integrated optical tweezers by over two orders of magnitude compared to prior work. [ABSTRACT FROM AUTHOR]

This study explores the frontiers of microparticle manipulation by introducing an actuator platform for the three-dimensional positioning of microparticles using dielectrophoresis (DEP), a technique known for its selectivity and ease of integration with microtechnology. Leveraging advancements in carbon-based devices due to their biocompatibility and electrochemical stability, our work extends the application of DEP from two-dimensional constraints to precise 3D positioning within microvolumes, employing a photolithography-based fabrication process known as Carbon-MEMS technology (C-MEMS). We present the design, finite element simulation, fabrication, and testing of this platform, which utilizes a unique combination of planar and 3D carbon microelectrodes individually addressable on a transparent substrate. This setup enables the application of DEP forces, allowing for high-throughput manipulation of multiple microparticles simultaneously, as well as displacement of individual microparticles in any desired direction. Demonstrated with spherical 1μm and 10μm diameter polystyrene microparticles, this platform features straightforward fabrication and is suitable for batch industrial production. The study concludes with a discussion of the platform's advantages and limitations, marking a significant step toward a valuable tool for studying complex biological systems. [ABSTRACT FROM AUTHOR]

Electrospun polystyrene (PS) fibers are produced using a mixed solvent of chloroform and n,n‐dimethylformamide (DMF) to investigate the influence of the solvent ratio on the fiber surface morphology and contact angle of the obtained mats. Electrospinning is a simple processing technique for producing fibers with diameters in the range of nanometers to a few micrometers. When using the different solvent ratios for this process, porous PS membranes are created due to nonsolvent and thermally induced phase separation (N‐TIPS). The morphology of the fibers is analyzed through scanning electron microscopy (SEM), which showed that fibers have diameters between 200 nm and 6 µm. SEM also revealed that the pores present on the surface of the fibers vary from densely compacted and well‐formed nanopores with diameters in the range of 20–50 nm to larger pores with sizes of ≈100–200 nm. The pore size varied with different solvent ratios. The surface area is analyzed using the Brunauer–Emmett–Teller (BET) method and found that the polymeric fibers have a high surface area (≈35 m2 g−1). The fibers with such morphology are highly hydrophobic, with a contact angle higher than 143°. These materials are excellent candidates for applications in textiles, filtration, and biomedical fields. [ABSTRACT FROM AUTHOR]

Background: There has been an exponential increase in the number of studies reporting on the toxicological effects associated with exposure to nano and microplastic particles (NMPs). The majority of these studies, however, have used monodispersed polystyrene microspheres (PSMs) as 'model' particles. Here we review the differences between the manufacture and resulting physicochemical properties of polystyrene used in commerce and the PSMs most commonly used in toxicity studies. Main body: In general, we demonstrate that significant complexity exists as to the properties of polystyrene particles. Differences in chemical composition, size, shape, surface functionalities and other aspects raise doubt as to whether PSMs are fit-for-purpose for the study of potential adverse effects of naturally occurring NMPs. A realistic assessment of potential health implications of the exposure to environmental NMPs requires better characterisation of the particles, a robust mechanistic understanding of their interactions and effects in biological systems as well as standardised protocols to generate relevant model particles. It is proposed that multidisciplinary engagement is necessary for the development of a timely and effective strategy towards this end. We suggest a holistic framework, which must be supported by a multidisciplinary group of experts to work towards either providing access to a suite of environmentally relevant NMPs and/or developing guidance with respect to best practices that can be adopted by research groups to generate and reliably use NMPs. It is emphasized that there is a need for this group to agree to a consensus regarding what might best represent a model NMP that is consistent with environmental exposure for human health, and which can be used to support a variety of ongoing research needs, including those associated with exposure and hazard assessment, mechanistic toxicity studies, toxicokinetics and guidance regarding the prioritization of plastic and NMPs that likely represent the greatest risk to human health. It is important to acknowledge, however, that establishing a multidisciplinary group, or an expert community of practice, represents a non-trivial recommendation, and will require significant resources in terms of expertise and funding. Conclusion: There is currently an opportunity to bring together a multidisciplinary group of experts, including polymer chemists, material scientists, mechanical engineers, exposure and life-cycle assessment scientists, toxicologists, microbiologists and analytical chemists, to provide leadership and guidance regarding a consensus on defining what best represents environmentally relevant NMPs. We suggest that given the various complex issues surrounding the environmental and human health implications that exposure to NMPs represents, that a multidisciplinary group of experts are thus critical towards helping to progress the harmonization and standardization of methods. [ABSTRACT FROM AUTHOR]

AbstractNanodiamonds are unique spherical carbon nano-entities having the advantages of very high surface area and high optical, thermal, wear and strength characteristics. Like other carbonaceous nanoparticles (like fullerene, graphene or carbon nanotube), nanodiamond nano-reinforcements have been investigated for the significant types of polymeric matrices (such as thermosets, thermoplastics, rubbers) nanocomposites. Consequently, this overview was planned to systematically describe the current scientific status of the nanodiamonds reinforced thermoplastic nanomaterials. In this regard, polyamide/nanodiamonds, polyimide/nanodiamonds and polystyrene/nanodiamonds nanocomposites have been fabricated using the facile solution, in-situ and melt mixing techniques. We suggest that including nanodiamonds in polyamides and polyimides increased their engineering characteristics, like mechanical properties and thermal stability, of the resulting nanocomposites due to a distinct interface formation and their compatibilization effects toward these matrices. Correspondingly, including nanodiamonds in polystyrene has been observed to increase the intrinsically low strength/toughness features of this polymer. Predominantly, nano-reinforcement and miscibility effects of the nanodiamonds with the polystyrene and their mutual matrix-nanofiller synergies were responsible to improve the overall microstructural and physical properties of the resulting nanocomposites. As per our analysis, the research reports so far on the important categories of the nanodiamonds reinforced thermoplastic matrix nanocomposites have shown important technical applications in the fields of high-tech coatings, membranes and energy devices. [ABSTRACT FROM AUTHOR]

Nanoplastics (NPs) are usually formed by the decomposition of large plastics, which will cause water pollution after entering the water body. Carbon filter column is used to adsorb and remove polystyrene nanoparticles (PSNPs). The influence of experimental conditions on adsorption was investigated and fitted by kinetic model. The results show that increasing the height of carbon filter column and decreasing the initial concentration of PSNPs and water flow rate can prolong the breakthrough time of carbon filter column. When the initial concentration of PSNPs is 0.8 mg L−1, the influent flow rate is 4 mL min−1 and the height of carbon filter bed is 8.5 cm, the removal effect is the best, and the depletion point of carbon filter column is extended to 48 h. Adams-Bohart model is suitable for describing the initial stage of adsorption. Thomas and Yoon-Nelson models can well describe the whole dynamic adsorption process of PSNPs, and Yoon-Nelson model can accurately predict the time required for 50% PSNPs to penetrate the carbon column. The adsorption mechanism of NPs by carbon filter column is mainly through the attachment sites and pore retention provided by particles on the surface of activated carbon. This study can provide new technical and theoretical support for the removal of NPs. [ABSTRACT FROM AUTHOR]

The stability issue of perovskite solar cells (PSCs) has long been of concern to researchers. Poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is commonly used as a hole transport layer (HTL) in the inverted PSCs to achieve efficient and stable performance. However, PEDOT:PSS can corrode ITO, affecting device efficiency. Moreover, the hydrophilic nature of PEDOT:PSS compromises device stability. In this work, Poly (3-hexylthiophene-2,5-diyl) (P3HT), known for its good hydrophobicity, was used to modify the surface of PEDOT:PSS, reducing its water absorption and thereby enhancing the efficiency and stability of PSCs. The results reveal that incorporating P3HT effectively enhances the hydrophobicity of PEDOT:PSS. Furthermore, it fosters the development of large-grain perovskite film on the PEDOT:PSS/P3HT bilayer. This enhancement leads to a power conversion efficiency (PCE) of 19.78% for PSCs, with an increase by 16% than that of reference cells (17.04% of PCE). Following a duration of 1000 h, the PCE for the device modified with P3HT remains above 90%, while the PCE of the reference device is below 70%. These findings suggest that using P3HT in conjunction with PEDOT:PSS as a bilayer HTL can concurrently and proficiently improve the efficiency and stability of PSCs. [ABSTRACT FROM AUTHOR]

Eco-friendly, nontoxic and high-energy storage materials are very important for flexible electrode materials. Bi4Ti3O12 lead-free, perovskite phase may prove suitable as filler in composites for electrode materials because of its large spontaneous polarization. We have synthesized Bi4Ti3O12/polystyrene (BTO/PS) composites and carried out their structural, morphological and bonding studies with the help of X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), in that order. Dielectric measurements in the broad frequency range of synthesized composites determined by Impedance analyzer. We observed that the dielectric constant of composites increased with filler concentration and decreased with applied field frequency. Bi4Ti3O12/PS composites can be good electrode materials. [ABSTRACT FROM AUTHOR]

A symmetric supercapacitor device with high electrochemical performance was assembled using the TC- P -3 hybrid film electrode. [Display omitted] Robust, conductive and flexible electrode materials have been the focus of attention in portable, wearable electronics. However, it is still a significant challenge to achieve synergistic development of multiple properties simultaneously. Herein, we propose a combination of microscale design and nanostructures strategy to prepare MXene/cellulose nanofiber-poly (3,4-ethylenedioxythiphoenes):polystyrene sulfonate (Ti 3 C 2 T x /CNF-PEDOT:PSS, TC-P) hybrid film by a simple in-situ polymerization and vacuum filtration process. CNF serves as the supporting skeleton of PEDOT:PSS, effectively mitigating its self-aggregation and structural deformation due to the expansion/contraction of the polymer network. And the CNF-PEDOT:PSS composite is capable to open up the interlayer space of Ti 3 C 2 T x , which reduces the self-stacking of Ti 3 C 2 T x nanosheets. The strong interactions among the three components enable the hybrid film electrode to possess both flexibility and high electrochemical properties. As a result, the film electrode exhibits a remarkable tensile strength of 77.4 MPa and an excellent conductivity of 162.5 S cm−1, as well as an outstanding areal specific capacitance of 896 mF cm−2 at 4 mA cm−2. Moreover, the assembled symmetric supercapacitor (SSC) device displays a large areal energy density of 62 µWh cm−2 at a power density of 800 µW cm−2 and demonstrates a long cycle life with 85.1 % capacitance retention after 10,000 GCD cycles. This study provides an effective strategy to balance mechanical flexibility and electrochemical properties, providing an inspiration to prepare flexible electrodes that are widely applied in a new generation of portable, wearable electronics. [ABSTRACT FROM AUTHOR]

Plastic waste has recently become a major global environmental concern and one of the biggest challenges has been seeking for alternative management options. Several studies have revealed the potential of several coleopteran species to degrade plastics, and this is the first research paper on plastic-degradation potential by lesser mealworms from Africa. This study evaluated the whole mitogenomic profile of the lesser mealworm to further identify the insect. The ability of the mealworm to consume Polystyrene (PS) was also evaluated alongside its associated gut microbiota diversity. Our results showed a complete circular mitochondrial genome which clustered closely to the Alphitobius genus but also suggested that our insect might be a new subspecies which require further identification. During the PS feeding trials, overall survival rates of the larvae decreased when fed a sole PS diet while PS intake was observed to increase over a 30-day period. The predominant bacteria observed in larvae fed PS diets were Kluyvera, Lactococcus, Klebsiella, Enterobacter, and Enterococcus, while Stenotrophomonas dominated the control diet. These findings demonstrated that the newly identified lesser mealworm can survive on a PS diet and has a consortium of important bacteria strongly associated with PS degradation. This work provides a better understanding of bioremediation applications, paving the way for further research into the metabolic pathways of plastic-degrading microbes and bringing hope to solving plastic waste pollution while providing high-value insect protein towards a circular economy. [ABSTRACT FROM AUTHOR]

Anthraquinone-based hollow COFs were synthesized via a template-assisted method involving polystyrene nanospheres as the hard template, which enabled doubling the specific capacitance and energy density compared to non-templated COFs. Our approach can be extended to other COFs, offering a promising strategy for enhancing the performance of COF-based electrodes in energy storage applications. [ABSTRACT FROM AUTHOR]

Polystyrene is a staple plastic in the packaging and insulation market. Despite its good recyclability, the willingness of PS recycling remains low, largely due to the high recycling cost and limited profitability. This review examines the research progresses, gaps, and challenges in areas that affect the recycling costs, including but not limited to logistics, packaging design, and policymaking. We critically evaluate the recent developments in upcycling strategies, and we particularly focus on tandem and hydrogen‐atom transfer (HAT) upcycling strategies. We conclude that future upcycling studies should focus on not only reaction chemistry and mechanisms but also economic viability of the processes. The goal of this review is to stimulate the development of innovative recycling strategies with low recycling costs and high economic output values. We hope to stimulate the economic and technological momentum of PS recycling towards a sustainable and circular economy. [ABSTRACT FROM AUTHOR]

The increasing use of contact lenses, artificial tears, and anti-vascular endothelial growth factor (anti-VEGF) drug injections for age-related macular degeneration has heightened the likelihood of eye exposure to microplastic particles. Extensive research has established that microplastic particles can induce oxidative stress on the ocular surface, resulting in damage. However, the impact of these particles on the retina remains unclear. Therefore, this study investigated whether microplastics/nanoplastics (MPs/NPs) cause retinal damage. In vitro human retinal pigment epithelial (RPE) cells were exposed to polystyrene MPs and NPs for 48 h. Assessment of cell viability using WST-8; evaluation of TNF-α and IL-1β expression; observation of cell morphology and particle invasion via TEM; measurement of ROS levels using the DCFDA reagent; and western blot analysis of SOD2, FIS1, Drp1, and LC3B expression were conducted. In vivo experiments involved intravitreal injection of MPs/NPs in rats, followed by retinal H&E staining 24 h later and evaluation of TNF-α and IL-1β expression. Results indicated that exposure to MPs did not significantly alter RPE cell viability, whereas exposure to NPs led to a noticeable decrease. TEM images revealed NPs' penetration into cells, causing increased oxidative stress (SOD2), mitochondrial fission (FIS1, Drp1), and mitochondrial autophagy (LC3B). In vivo experiments demonstrated an increase in inflammatory cells in retinal tissues exposed to NPs, along with elevated levels of TNF-α and IL-1β. Conclusively, both MPs and NPs impact the retina, with NPs displaying greater toxicity. NPs significantly elevate ROS levels in the retina and induce mitochondrial fission and mitophagy in RPE cells compared to MPs. [ABSTRACT FROM AUTHOR]

Polystyrene particles (EPS) were used as the doping material, which were hydrophilic modified by different surfactants. On this basis, polystyrene particles were added to foam concrete, and the effects of hydro¬philic modified polystyrene particles on the mechanical properties and thermal insulation performance of concrete were studied. The results showed that unmodified polystyrene belongs to hydrophobic materials with a contact angle of 112°. After modification with triethanolamine, the contact angle decreased to 31°, indicating ex¬cellent hydrophilicity. Foam concrete had porous characteristics, and the pore size distribution was 20-230 µm. The setting time decreased with the increase of polystyrene particle doping, the fluidity first increased and then decreased, the solidification time of EPS-0.9% was 90 minutes, and the highest fluidity was 17.9 mm. With the increase of EPS particles, the compressive strength of foam concrete continued decreasing, the flexural strength first decreased and then slightly increased, the thermal conductivity and dry density first decreased and then increased, and the carbonation resistance continued decreasing. At 28 d of age, the compressive strength of the EPS-1.2% sample reached the minimum value of 5.2 MPa, and the carbonization depth reached the maximum value of 2.13 mm. The flexural strength of the EPS-0.6% sample reached a maximum value of 0.57 MPa. The dry density and thermal conductivity of the EPS-0.9% sample reached the lowest values, which were 357 kg/m³ and 0.069 W/(m • K), respectively, indicating the best insulation performance. [ABSTRACT FROM AUTHOR]

While there are a number of available reference and testing materials for micro- and nanoplastic (MNP) studies in toxicology, they are not well-characterized and do not cover all major polymer types that may potentially pollute the environment. This review article will address the question of why we need properly designed synthesized micro- and nanoplastics with a core–shell structure (with organic–inorganic units) and provide researchers with a scientific basis for the design of synthesized MNP particles. It will include a list of commercially available MNPs, an overview of the theoretical background to polymer particle synthesis, and an analysis of the advantages and disadvantages of MNP preparation methods, namely, fragmentation and synthesis, along with examples of synthesized MNP particles. The current study will demonstrate that polystyrene is one of the most prevalent MNP particle types among reference materials from certification bodies and among testing particles synthesized by chemical scientists. Nevertheless, the global industrial production of polystyrene represents approximately 5% of the total, and it is not a dominant plastic type in the textile or packaging industries. In contrast to mechanically fragmented MNP particles, the synthesis approach offers the potential to control the physico-chemical properties, enabling the more selective detection and quantification, as well as a greater comparability of the results amongst toxicological studies. [ABSTRACT FROM AUTHOR]

In physical foaming processes of thermoplastics, a liquid mixture consisting of a molten polymer with a dissolved blowing agent is extruded through a die or injected into a mold. The morphology of the foam matrix strongly depends on the mutual diffusion coefficient D11 of the liquid polymer-blowing agent mixture. For a better understanding of the underlying physical mechanisms during the foaming process and the development of corresponding models, accurate knowledge of D11 is needed. This work reports on the simultaneous measurement of D11 and the thermal diffusivity a of liquid mixtures consisting of polystyrene melts with dissolved nitrogen (N2) or carbon dioxide (CO2) at mass fractions wsolute up to 0.003 or 0.02 and temperatures T between (433 and 533) K using dynamic light scattering (DLS). The determined D11 range is between (1 and 4) × 109 m2⋅s−1 and are slightly larger for the mixtures containing N2 at a given T and wsolute. D11 could be determined with an average expanded relative uncertainty of 18%. Considering all investigated state points and the achieved experimental uncertainties, both D11 and a are independent on the amount of dissolved gas, despite relatively large mole fractions of the dissolved blowing agents xsolute of 0.997 and 0.93. [ABSTRACT FROM AUTHOR]

In the present study, the effect of gamma irradiation and 90 MeV carbon ion beam irradiation on electrical properties and optical of Polystyrene/Eu2O3 nanocomposites at different fluences were examined. Modified electrical and optical responses of polymer nanocomposites were investigated using Impedance, Photoluminescence and UV-VIS spectroscopies. FTIR analysis shows a reduction of various modes of molecular vibrations caused by 90 MeV carbon ion beam irradiation. The polymer nanocomposites change into a graphite-like structure upon both kinds of irradiations as evidenced by the decrease in the optical band gap. The photoluminescence emission spectra show three characteristic peaks of Eu3+ ions, when excited at 247 nm wavelength. It emits intense red light suggesting its potential for usage in LED technology. The peak intensity of PL emission spectra is enhanced after ion beam irradiation and is because of the formation new radiative combination; however, it decreases upon gamma irradiation. Dielectric responses of pristine and irradiated polymer nanocomposites were studied over the frequency range of 100 Hz to 100 kHz using LCR meter. There appears a significant improvement in the dielectric response as a result of structural changes in both types of irradiations. AFM images show that the film becomes smoother upon both types of irradiations. [ABSTRACT FROM AUTHOR]

The linear and nonlinear shear rheology of entangled polystyrene (PS) solutions diluted by styrene oligomers with various lengths was compared with the shear rheology of a pure melt having the same number of entanglements (Z) during startup shear and step-shear strain experiments using a cone partitioned-plate geometry. By fixing the same Z, the shear rheology of the PS solutions and the melt shows some universal features in the linear and nonlinear regimes. Undershoot of the shear stress growth coefficient is observed during the startup flow of the PS solutions and depends strongly on the length of the oligomers. The Rotation Zero Stretch model captures the stress overshoot and the steady shear viscosity quantitatively, except at the high shear rates when undershoot is observed. Stress relaxation after step-shear strain experiments reveals that the PS solutions show a transition from type A damping (close to the Doi–Edwards prediction) to type B (weaker than the Doi–Edwards prediction), while the pure melt having the same Z shows a type A response, which suggests that the length of the oligomers influences the nonlinear damping response. The nonuniversality of the nonlinear damping response of the solutions and the melt is possibly due to the changes in flow-induced friction reduction during step-shear strain deformation. [ABSTRACT FROM AUTHOR]

The study primarily focuses on the in situ synthesis of polystyrene (PS) and copper oxide (CuO) nanocomposites. An extensive analysis was conducted on the optical, thermal, mechanical, and electrical properties of PS with different CuO concentrations. The effective inclusion of CuO into PS was characterized by Fourier-transform infrared spectroscopy (FTIR), UV–visible spectroscopy, filed emission scanning electron microscopy (FE-SEM), X-ray diffractometry (XRD), differential scanning calorimetric analysis (DSC) and thermal gravimetric analysis (TGA). The reinforcement of CuO into the PS was established through FTIR. The optical bandgap energy deduced from UV–visible spectra decreases with CuO addition, whereas the refractive index rises significantly with the addition of CuO nanoparticles up to 7 mass%. The XRD analysis revealed the amorphous to crystalline transformation of PS with the homogeneous dispersion of nanoparticles. The SEM–EDX analysis revealed the uniform distribution of CuO nanofillers in the PS matrix. The CuO addition considerably increased the glass transition temperature and thermal stability of PS. The tensile strength, impact resistance and hardness of nanocomposite were significantly increased with the loading of CuO in the polymer matrix. The AC conductivity and dielectric constant of the PS was improved with the addition of CuO nanoparticles. The effect of temperature on conductivity, activation energy, and pre-exponential factor was determined using the universal power law and the Arrhenius equation. The highest electrical and mechanical properties were observed for 7 mass% nanocomposite. The synthesized PS/CuO nanocomposites with excellent optical characteristics, thermal stability, electrical conductivity, dielectric constant and mechanical strength can be used in supercapacitors and flexible nano-electronic devices. [ABSTRACT FROM AUTHOR]