Chronic exposure to tire rubber-derived contaminant 6PPD-quinone impairs sperm quality and induces the damage of reproductive capacity in male mice.

It has been reported that N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q), a derivative of the tire antioxidant, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), exhibits acute toxicity towards organisms. However, the possible reproductive toxicity of 6PPD-Q in mammals has rarely been reported. In this study, the effects of 6PPD-Q on the reproductive toxicity of C57Bl/6 male mice were assessed after exposure to 6PPD-Q for 40 days at 4 mg/kg body weight (bw). Exposure to 6PPD-Q not only led to a decrease in testosterone levels but also adversely affected semen quality and in vitro fertilization (IVF) outcomes, thereby indicating impaired male fertility resulting from 6PPD-Q exposure. Additionally, transcriptomic and metabolomic analyses revealed that 6PPD-Q elicited differential expression of genes and metabolites primarily enriched in spermatogenesis, apoptosis, arginine biosynthesis, and sphingolipid metabolism in the testes of mice. In conclusion, our study reveals the toxicity of 6PPD-Q on the reproductive capacity concerning baseline endocrine disorders, sperm quality, germ cell apoptosis, and the sphingolipid signaling pathway in mice. These findings contribute to an enhanced understanding of the health hazards posed by 6PPD-Q to mammals, thereby facilitating the development of more robust safety regulations governing the utilization and disposal of rubber products.

Leaching behavior of metals from asphalt mixtures modified with crumb rubber from scrap tires.

There are concerns about the potential toxicity of bitumen and recycled materials such as reclaimed asphalt pavements from end-of-life roads and crumb rubber from scrap tires used in asphalt mixtures because they contain metals that may be released into the groundwater. This study investigated the potential metal leaching of laboratory-prepared asphalt mixtures modified with polymer coated rubber (PCR) with wet and dry technology, devulcanized rubber (DVR), compared to an unmodified control mixture and a blend modified with a synthetic polymer (SBS). The objectives were to i) quantify concentrations of metals released, ii) calculate the flux rate, the cumulative mass release, and the assessment ratio for each metal, iii) verify if the metals exceeded the EPA drinking water limit, and, finally, iv) assess the source of metals release. Zinc had the highest concentration among all metals and was present in eluates from all mixtures. The cumulative zinc concentration from DVR mixture was 41% and 34% higher than the control and SBS mixtures, respectively. For PCR wet, the cumulative zinc concentration was 9% higher than the control blend and 1% lower than the SBS mix. The assessment ratio indicated that all metal concentrations would not exceed the drinking water limit, except for zinc, for which further evaluations were required. The main source of zinc may derive from aggregates. This work showed that crumb rubber might not be the only source of metal leaching, and its use in asphalt pavements does not cause a metal leaching higher than other materials.

New design of interdental rubber picks - does the archimedean screw design bring an improvement for experimental cleaning efficacy and force?

BACKGROUND: Up to date, interdental brushes (IDB) are the first choice for interdental cleaning because of their cleaning efficacy. Cylindrical ones must be selected individually according to the size/morphology of the interdental area (IDR), whereas conical ones cover a larger variability of IDR. However, there is a trend on the part of patients towards interdental rubber picks (IRP) which are in general conically shaped, and which seem to be linked with lower cleaning efficacy. A new IRP with an Archimedes´ screw design was developed to overcome this limitation. Therefore, the in vitro study aimed to measure the experimental cleaning efficacy (ECE) and force (ECF) during interdental use of IDBs versus the new IRP type. METHODS: Three IRPs with different tapers (PHB angled: 0.039, PHB straight S: 0.027, Vitis straight M: 0.045; all Flexipicks, Dentaid, Cerdanyola del Vallès, Spain) were compared to one IDB (Interprox micro PHD 0.9, Dentaid, Cerdanyola del Vallès, Spain). IDR were reproduced by a 3D-printer (Form2, Formlabs Sommerville, MA, USA) according to human teeth and matched to equivalent pairs (isosceles triangle, concave, convex) in three different diameters (1.0 mm,1.1 mm,1.3 mm). Covered with simulated biofilm, pre-/ post-brushing situations of IDR (standardized, computer-aided ten cycles) were photographed and quantified by digital image subtraction to calculate ECE [%]. ECF were registered with a load cell [N]. Statistically significant differences were detected using the Mann-Whitney-U-test and the Kruskal-Wallis-test with Bonferroni correction for multiple testing. RESULTS: Overall, the ECE (mean ± SD) was higher for IDB micro 0.9 (45.95 ± 11.34%, p < 0.001) compared to all IRPs (PHB angled: 25.37 ± 15.29%; PHB straight: 22.28 ± 16.75%; Vitis straight: 25.24 ± 12.21%; p ≤ 0.001), whereat best ECE was achieved in isosceles triangle IDR of 1.0-1.1 mm (IDB micro 0.9: 70.7 ± 7.7%; PHB angled S: 57.30 ± 4.43%; p < 0.001). The highest ECF occurred for Vitis straight M with 2.11 ± 0.46 N, while IDB micro 0.9 showed lowest ECF values (0.64 ± 0.14 N; p < 0.001). CONCLUSIONS: IRP with an Archimedes´ screw design and a higher taper were associated with advanced ECE but also higher ECF, nevertheless, ECE didn't reach the cleaning efficacy of conventional IDBs.

The large-scale expansion of rubber plantations in southern India: major impacts and the changing nature of drivers.

This study investigates the major environmental and socio-economic impacts of an increase in the area of rubber plantations and the changing patterns of drivers of land use changes. Using a combination of geospatial techniques and socio-economic methods, we mainly analyzed the rate of increase in area under rubber plantations, the major impacts of land use changes, and the changing drivers of land use changes. Our results show that the area under rubber plantations has increased significantly within the study area, with the area under rubber plantations increasing from 30 to 74% of the total area within five decades. Impact assessment of land use changes based on household surveys showed significant improvement in the socio-economic conditions of the farmers, however, at the expense of severe environmental degradation. Our results also indicate that while areas under rubber plantations continue to increase, the drivers of land use changes have changed over time. Furthermore, it has been observed that in the past, many interventions prioritized social and economic development and placed less emphasis on the ecological stability of the region. Perceptions of farmers revealed that the effects of ecological fragility already affected the economic robustness of the whole area. Therefore, we conclude that government interventions to support additional rubber cultivation should also focus on ecosystem stabilization in order to minimize the risk of an ecological catastrophe that would significantly affect the economic prosperity of the region.

Methacrylic acid in situ modified steel converter slag/natural rubber composites: Resourceful utilization of steelmaking solid wastes.

As a by-product of the steelmaking industry, the large-volume production and accumulation of steel converter slag cause environmental issues such as land occupation and dust pollution. Since metal salts of unsaturated carboxylic acid can be used to reinforce rubber, this study explores the innovative application of in-situ modified steel slag, mainly comprising metal oxides, with methacrylic acid (MAA) as a rubber filler partially replacing carbon black. By etching the surface of steel slag particles with MAA, their surface roughness was increased, and the chemical bonding of metal methacrylate salt was introduced to enhance their interaction with the molecular chain of natural rubber (NR). The results showed that using the steel slag filler effectively shortened the vulcanization molding cycle of NR composites. The MAA in-situ modification effectively improved the interaction between steel slag and NR molecular chains. Meanwhile, the physical and mechanical properties, fatigue properties, and dynamic mechanical properties of the experimental group with MAA in-situ modified steel slag (MAA-in-situ-m-SS) were significantly enhanced compared with those of NR composites partially filled with unmodified slag. With the dosage of 7.5 phr or 10 phr, the above properties matched or even exceeded those of NR composites purely filled with carbon black. More importantly, partially replacing carbon black with modified steel slag reduced fossil fuel consumption and greenhouse gas emission from carbon black production. This study pioneered an effective path for the resourceful utilization of steel slag and the green development of the steelmaking and rubber industries.

Study of sequential abiotic and biotic degradation of styrene butadiene rubber.

Styrene butadiene rubber is one of the main constituents of tire tread. During tire life, the tread material undergoes different stresses that impact its structure and chemical composition. Wear particles are then released into the environment as weathered material. To understand their fate, it is important to start with a better characterization of abiotic and biotic degradation of the elastomer material. A multi-disciplinary approach was implemented to study the photo- and thermo- degradation of non-vulcanized SBR films containing 15 w% styrene as well as their potential biodegradation by Rhodoccocus ruber and Gordonia polyisoprenivorans bacterial strains. Each ageing process leads to crosslinking reactions, much surface oxidation of the films and the production of hundreds of short chain compounds. These degradation products present a high level of unsaturation and oxidation and can be released into water to become potential substrates for microorganisms. Both strains were able to degrade from 0.2 to 1.2 % (% ThOD) of the aged SBR film after 30-day incubation while no biodegradation was observed on the pristine material. A 25-75 % decrease in the signal intensity of water extractable compounds was observed, suggesting that biomass production was linked to the consumption of low-molecular-weight degradation products. These results evidence the positive impact of abiotic degradation on the biodegradation process of styrene butadiene rubber.

Transformation scenarios towards multifunctional landscapes: A multi-criteria land-use allocation model applied to Jambi Province, Indonesia.

In tropical regions, shifting from forests and traditional agroforestry to intensive plantations generates conflicts between human welfare (farmers' demands and societal needs) and environmental protection. Achieving sustainability in this transformation will inevitably involve trade-offs between multiple ecological and socioeconomic functions. To address these trade-offs, our study used a new methodological approach allowing the identification of transformation scenarios, including theoretical landscape compositions that satisfy multiple ecological functions (i.e., structural complexity, microclimatic conditions, organic carbon in plant biomass, soil organic carbon and nutrient leaching losses), and farmers needs (i.e., labor and input requirements, total income to land, and return to land and labor) while accounting for the uncertain provision of these functions and having an actual potential for adoption by farmers. We combined a robust, multi-objective optimization approach with an iterative search algorithm allowing the identification of ecological and socioeconomic functions that best explain current land-use decisions. The model then optimized the theoretical land-use composition that satisfied multiple ecological and socioeconomic functions. Between these ends, we simulated transformation scenarios reflecting the transition from current land-use composition towards a normative multifunctional optimum. These transformation scenarios involve increasing the number of optimized socioeconomic or ecological functions, leading to higher functional richness (i.e., number of functions). We applied this method to smallholder farms in the Jambi Province, Indonesia, where traditional rubber agroforestry, rubber plantations, and oil palm plantations are the main land-use systems. Given the currently practiced land-use systems, our study revealed short-term returns to land as the principal factor in explaining current land-use decisions. Fostering an alternative composition that satisfies additional socioeconomic functions would require minor changes ("low-hanging fruits"). However, satisfying even a single ecological indicator (e.g., reduction of nutrient leaching losses) would demand substantial changes in the current land-use composition ("moonshot"). This would inevitably lead to a profit decline, underscoring the need for incentives if the societal goal is to establish multifunctional agricultural landscapes. With many oil palm plantations nearing the end of their production cycles in the Jambi province, there is a unique window of opportunity to transform agricultural landscapes.

Advancing image segmentation with DBO-Otsu: Addressing rubber tree diseases through enhanced threshold techniques.

Addressing the profound impact of Tapping Panel Dryness (TPD) on yield and quality in the global rubber industry, this study introduces a cutting-edge Otsu threshold segmentation technique, enhanced by Dung Beetle Optimization (DBO-Otsu). This innovative approach optimizes the segmentation threshold combination by accelerating convergence and diversifying search methodologies. Following initial segmentation, TPD severity levels are meticulously assessed using morphological characteristics, enabling precise determination of optimal thresholds for final segmentation. The efficacy of DBO-Otsu is rigorously evaluated against mainstream benchmarks like Peak Signal-to-Noise Ratio (PSNR), Structural Similarity Index (SSIM), and Feature Similarity Index (FSIM), and compared with six contemporary swarm intelligence algorithms. The findings reveal that DBO-Otsu substantially surpasses its counterparts in image segmentation quality and processing speed. Further empirical analysis on a dataset comprising TPD cases from level 1 to 5 underscores the algorithm's practical utility, achieving an impressive 80% accuracy in severity level identification and underscoring its potential for TPD image segmentation and recognition tasks.

A nation-wide study for the occurrence of PPD antioxidants and 6PPD-quinone in road dusts of China.

N,N'-substituted p-phenylenediamines (PPDs) are widely used antioxidants in rubber tires, which could be released and accumulated in road dusts with rubber tires wear. As ozonation product of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), 6PPD-quinone (6PPD-Q) exhibited higher toxicity to coho salmon. However, studies on their environmental behaviors are still limited. Road dust is the major medium PPDs exist, which significantly affects the levels of PPDs in other mediums, especially surface water and particulate matter. In this study, road dust samples were collected in 55 major cities of China to explore the distribution characteristics of PPDs and 6PPD-Q. The concentrations of total PPDs (ΣPPDs) and 6PPD-Q in urban trunk road dust samples were in the ranges of 7.90-727 and 3.00-349 ng/g, with median concentrations of 68 and 49 ng/g, respectively. 6PPD and 6PPD-Q are the dominant components in most road dusts. The functional region-dependent pollution characteristics of PPDs and 6PPD-Q give the first finding that urban tunnel road was the highly polluted region, followed by urban trunk roads. Suburban road dusts had a lower pollution level. Moreover, the estimated daily intake (EDI) of PPDs and 6PPD-Q for children was much higher than adults.

Enhancement in antimicrobial efficacy and biodegradation of natural rubber latex through graphene oxide/nickel oxide nanoparticles.

This work aims to fabricate antibacterial natural rubber latex composites by introducing different ratios of graphene oxide (GO) and nickel oxide (NiO) nanoparticles. The nanocomposites were prepared using latex mixing and a two-roll mill process, followed by molding with a heating hydraulic press. Detailed analyses were conducted to evaluate the rheological, chemical, physical, thermal, mechanical, and electrical performance of the composites. Fourier transform infrared spectroscopy (FTIR) was employed to analyze the interaction among different components, while the surface morphology was examined through the field emission scanning electron microscopy (FESEM) technique. The composites with a loading ratio of 1:2 of GO to NiO (optimized concentration) exhibited the highest tensile strength (24.9 MPa) and tear strength (47.4 N/ mm) among all the tested samples. In addition, the composites demonstrated notable antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The thermal stability of the composites was observed up to 315 °C, and their electrical resistivity lies in the insulating range across a temperature span of 25 °C to 50 °C. The research uncovers critical insights into advancing composite materials suitable for diverse applications, featuring inherent antibacterial attributes, robust mechanical properties, resilience to solvent, UV shielding properties, and controlled electrical resistivity capabilities.

A novel complex coupling agent for enhancing the compatibility between collagen fiber and natural rubber: A utilization strategy for leather wastes.

Leather shavings are generated as solid waste in the leather industry and may cause environmental pollution if not disposed judiciously. These solid wastes, primarily composed of collagen fibers (CFs), can be recycled as biomass composites. However, CFs are incompatible with natural rubber (NR) due to its hydrophilicity. Conventionally, the compatibility has been improved by utilizing silane coupling agents (SCAs) along with a large number of organic solvents, which further contribute to environmental pollution. In this study, we developed a novel complex coupling agent (CCA) to enhance the compatibility between CF and NR. The CCA was synthesized through a coordination reaction between Cr(III) and α-methacrylic acid (MAA). Cr(III) in the coupling agent coordinates with the active groups in CFs, while the unsaturated double bonds in MAA facilitate covalent crosslinking between the CCA and NR, improving compatibility. The coordination bonding between CF and NR exhibits strong interfacial interaction, endowing the composites with desirable mechanical properties. Moreover, the proposed method is an economical and green approach that can be used to synthesize CF-based composites without requiring organic solvents. Herein, a strategy promoted sustainable development in the leather industry has been established.

Four new species of Utivarachna Kishida, 1940 (Araneae: Trachelidae) from Sumatra.

Four new species of trachelid spiders belonging to the genus Utivarachna Kishida, 1940 are described: U. angsoduo sp. nov., U. balonku sp. nov., U. rimba sp. nov., and U. trisula sp. nov. Part of the EFForTS project, the spider specimens were uncovered in a canopy fogging collection of tree crown arthropods along a land-use gradient from rainforest via jungle rubber (rubber agroforestry) to monocultures of rubber and oil palm in Jambi Province, Sumatra, Indonesia. Three of the proposed new species were found exclusively in rainforest or jungle rubber agroforest (U. angsoduo sp. nov., U. rimba sp. nov., U. trisula sp. nov.), and one of them exclusively in monocultures of rubber trees (U. balonku sp. nov.). We provide photographs and distribution maps for the proposed new species, and discuss their potential ecology based on their sampling locations. We also encountered a fifth species of the genus in all four land-use systems, U. phyllicola Deeleman-Reinhold, 2001, one of two species of the genus previously recorded from Sumatra, and also provide photographs and distribution maps for this species in the research area of the EFForTS project.

Overexpression of HbGRF4 or HbGRF4-HbGIF1 Chimera Improves the Efficiency of Somatic Embryogenesis in Hevea brasiliensis.

Transgenic technology is a crucial tool for gene functional analysis and targeted genetic modification in the para rubber tree (Hevea brasiliensis). However, low efficiency of plant regeneration via somatic embryogenesis remains a bottleneck of successful genetic transformation in H. brasiliensis. Enhancing expression of GROWTH-REGULATING FACTOR 4 (GRF4)-GRF-INTERACTING FACTOR 1 (GIF1) has been reported to significantly improve shoot and embryo regeneration in multiple crops. Here, we identified endogenous HbGRF4 and HbGIF1 from the rubber clone Reyan7-33-97, the expressions of which dramatically increased along with somatic embryo (SE) production. Intriguingly, overexpression of HbGRF4 or HbGRF4-HbGIF1 markedly enhanced the efficiency of embryogenesis in two H. brasiliensis callus lines with contrasting rates of SE production. Transcriptional profiling revealed that the genes involved in jasmonic acid response were up-regulated, whereas those in ethylene biosynthesis and response as well as the S-adenosylmethionine-dependent methyltransferase activity were down-regulated in HbGRF4- and HbGRF4-HbGIF1-overexpressing H. brasiliensis embryos. These findings open up a new avenue for improving SE production in rubber tree, and help to unravel the underlying mechanisms of HbGRF4-enhanced somatic embryogenesis.

Chromolaena odorata layered-nitrile rubber polymer transdermal patch enhanced wound healing in vivo.

The objective is to investigate the healing efficacy of a Chromolaena odorata layered-nitrile rubber transdermal patch on excision wound healing in rats. Wounds were induced in Sprague-Dawley rats and were later treated as follows: wound A, the negative control, received no treatment (NC); wound B, the negative control with an empty nitrile rubber patch (NC-ERP); wound C, treated with a C. odorata layered-nitrile rubber patch (CO-NRP); and wound D, the positive control with Solcoseryl gel with a nitrile rubber patch (PC-SG-NRP). After 1, 3, 6, 10, and 14 days, the rats were sacrificed and analyzed for wound contraction, protein content, hexosamine, and uronic acid levels. Macroscopic observation showed enhanced wound healing in wounds treated with CO-NRP with a wound contraction percentage significantly higher (p<0.05) on days 6 and 10 compared to those treated with NC-ERP. Similarly, protein, hexosamine, and uronic acid contents were also significantly higher (p<0.05) in CO-NRP-treated wounds when compared with wounds treated with NC-ERP. Histological findings showed denser collagen deposition and faster granulation tissue formation in wounds treated with CO-NRP. From the results obtained, it is concluded that the C. odorata layered-nitrile rubber transdermal patch was effective in healing skin wounds.

Preparation of UV-cured cellulose nanocrystal-filled epoxidized natural rubber and its application in a triboelectric nanogenerator.

Cellulose nanocrystal (CNC) is an abundant biopolymer possessing high strength and biodegradability. In the present work, the extraction of CNCs from Napier grass stems was carried out. The CNCs were subsequently modified by maleic anhydride, called M-CNC, before being incorporated into the epoxidized natural rubber (ENR). The compounds were later cured by ultraviolet (UV) irradiation under various conditions. The obtained optimum condition was then used to fabricate the biocomposites filled with various CNC and M-CNC loadings for triboelectric nanogenerator (TENG) performance measurements. Output voltage and current increased continuously with increasing filler loading. Regardless of the filler type, an increase in filler loading enhanced TENG output. ENR/M-CNC exhibited a superior TENG output to ENR/CNC due to the greater electron transfer capability of the biocomposites, as proven by the reduction in the ionization potential (IP) value obtained from the quantum calculation. In this study, ENR/M-CNC5 exhibited the maximum output voltage (80.3 V), current (7.4 µA), and power density (1.32 W/m2) at a load resistance of 9 MΩ.

Impact of air-polishing using erythritol on surface roughness and substance loss in dental hard tissue: An ex vivo study.

This ex vivo study aimed to investigate surface roughness and substance loss after treatment with different professional cleaning methods and to determine whether subsequent polishing with a rubber cup and polishing paste is necessary. Samples (flat and natural surfaces) of human enamel and dentin were prepared (baseline) and treated with either a curette, air-polishing with erythritol, a rubber cup and polishing paste, or a combination thereof (treatment). Subsequently, all samples were immersed in an ultrasonic bath (ultrasonic) to remove residues from the treatment procedures. The surface roughness values sRa and sRz as well as tissue loss were measured profilometrically. Linear regression models were used to compare group differences (roughness and loss) considering the corresponding baseline value. The significance level was set at p<0.05. sRa increased significantly after treatment with curettes or air-polishing with erythritol in both enamel (p<0.001) and dentin (p<0.001) of flat samples. The same effect was observed for sRz in dentin (p<0.001) but not for enamel compared to negative control. Polishing with a rubber cup and paste alone had no significant effect on roughness values. When combined with other treatments, the effect of curette or air-polishing with erythritol dominated the effect. In enamel, none of the tested methods led to measurable tissue loss. In dentin, air-polishing with erythritol caused ≤50% tissue loss compared to the curette. Conclusively, for enamel, treatment effects on roughness were measurable but of limited clinical relevance. For dentin, air-polishing resulted in a smaller but insignificant roughness increase and less tissue loss compared to the curette. Polishing with a rubber cup and paste did not affect surface roughness. Regarding the clinical application, the use of air-polishing seems to be a less invasive procedure than using a curette; polishing with rubber cup and paste offers no advantage in terms of reducing roughness as a final procedure.

Synthetic and natural rubber associated chemicals drive functional and structural changes as well as adaptations to antibiotics in in vitro marine microbiomes.

The leaching of additives from plastics and elastomers (rubbers) has raised concerns due to their potential negative impacts on the environment and the development of antibiotic resistance. In this study, we investigated the effects of chemicals extracted from two types of rubber on microbiomes derived from a benthic sea urchin and two pelagic fish species. Additionally, we examined whether bacterial communities preconditioned with rubber-associated chemicals displayed adaptations to antibiotics. At the highest tested concentrations of chemicals, we observed reduced maximum growth rates and yields, prolonged lag phases, and increased alpha diversity. While the effects on alpha and beta diversity were not always conclusive, several bacterial genera were significantly influenced by chemicals from the two rubber sources. Subsequent exposure of sea urchin microbiomes preconditioned with rubber chemicals to the antibiotic ciprofloxacin resulted in decreased maximum growth rates. This indicates a more sensitive microbiome to ciprofloxacin when preconditioned with rubber chemicals. Although no significant interaction effects between rubber chemicals and ciprofloxacin exposure were observed in bacterial alpha and beta diversity, we observed log-fold changes in two bacterial genera in response to ciprofloxacin exposure. These findings highlight the structural and functional alterations in microbiomes originating from various marine species when exposed to rubber-associated chemicals and underscore the potential risks posed to marine life.

Effective role of tannic acid in the fabrication of hydrophobic, oleophilic, antibacterial, boron nitride/chlorobutyl rubber nanocomposite for reusable protective clothing and oil-water separation.

Boron Nitride (h-BN) possesses unique qualities like increased thermal conductivity, non-toxic nature, and environmental friendliness; hence, it is a good reinforcing agent for chlorobutyl rubber (CIIR). Tannic acid (TA) holds excellent bio-functional properties and is considered as an exceptional bio-exfoliating agent. Hence, in this study, we have utilized the bio-exfoliating ability of TA to exfoliate h-BN and evaluate its efficiency in reinforcing the CIIR matrix. Results demonstrate the exceptional role of tannic acid in imparting multifunctionality to chlorobutyl rubber. CIIR matrix introduced with h-BN:TA (h-BN:TA/CIIR) display excellent mechanical performance due to the reinforcing effect shown by excess TA in addition to the exfoliating effect. In addition, h-BN:TA/CIIR composite exhibited superior antimicrobial activity against S. aureus. The retention of thermal decontamination efficiency of the composites with increase in the number of cycles ensures their promising application in the field of reusable gloves and chemical protective clothing. The exfoliated filler created a tortuous path inside the matrix which prevents the permeation of solvent. Hence the work intends to synergize the hydrophobic nature of h-BN, exfoliating capacity of TA and the barrier abilities of CIIR for the adsorption of oil from oil-water mixture and portrays the future of the trio in water purification.

Development of biodegradable packaging films from carboxymethyl cellulose and oxidised natural rubber latex.

The present study investigates the biopolymer packaging film developed from carboxymethyl cellulose (CMC) with varying concentrations of natural rubber latex (NR) and oxidised natural rubber latex (ONR) using the solvent casting method. The physicochemical properties of the CMC/NR and CMC/ONR film samples were characterised using FTIR, TG/DTA, DSC, SEM, and XRD analysis. The increased concentration of NR and ONR helped to enhance mechanical characteristics, superior UV resistance, enhanced resistance to oxygen and water vapour penetration, improved dimensional stability, and a reduction in the moisture retention ability of the film samples. The CMC sample film, incorporated with 1.5 g ONR, was found to have more than a 100 % increase in the tensile strength. The tensile value increased from 21.56 MPa to 48.36 MPa, with the highest young modulus of 0.73 GPa and elastic stability of 7.14 %. The incorporation of NR and ONR significantly reduced the super water absorbency nature of the CMC film, and the moisture content values reduced from 21.6 % to ≅ 0.15 % for ONR-incorporated film. Additionally, the CMC/NR and CMC/ONR films exhibited high optical transparency values and were found to be fast biodegradable, substantiating their potential use in various packaging applications. Application of these materials in perishable fruit packaging has shown significant enhancement in shelf life, highlighting their practical efficiency and potential for sustainable packaging solutions.

Types and concentrations of tire wear particles (TWPs) in road dust generated in slow lanes.

Drivers commonly navigate their vehicles at moderate speeds in proximity to traffic lights. In this study, road dust samples were collected in the vicinity of traffic lights, as well as at a taxi stand (TS) situated between traffic lights, with considerations given to both forward direction (FD) and backward direction (BD). The characterization of tire wear particles (TWPs) in the road dust was meticulously conducted based on particle size. Notably, tire-road wear particles (TRWPs) were conspicuously absent in samples surpassing 500 µm. Furthermore, TRWPs comprised less than 1% of identified particles in the road dust samples of 212-500 µm, with their origin traceable to heavy vehicles rather than passenger cars. The abundance of TRWPs from heavy vehicles exhibited marked variations, with heightened prevalence in the TS and BD samples as opposed to the FD sample. For the samples smaller than 212 µm, the composition of natural rubber (NR) in TWPs demonstrated a diminishing trend with escalating particle size. Conversely, the composition of styrene-butadiene rubber (SBR) exhibited an upward trajectory independent of the sampling site. The NR composition ratio in TWPs followed the order: TS (17-55%) > FD (17-47%) > BD (13-36%), while the SBR composition ratio exhibited the sequence: BD (62-86%) > FD (48-79%) > TS (24-70%). The TWP concentrations in road dust obtained from the TS (0.35-0.82%) were discernibly lower than those in the FD (0.54-1.77%) and BD (0.61-1.29%) samples. Specifically, the average TWP concentrations in road dust samples, falling within the size range of 20-212 µm, were 0.45%, 1.06%, and 0.91% for the TS, FD, and BD samples, respectively. These concentrations were lower than the corresponding values observed in samples collected from a bus stop.