Slow Degradation Research Articles

Development and Characterization of Gadolinium and Copper Reinforced Bioactive Glass: An In Vitro Study.

Bioactive glass, an innovative alloplastic material utilizing a matrix of silica particles combined with calcium and phosphorus, has been widely employed for the regeneration of bony defects due to its bone-forming capabilities and biocompatibility. Nevertheless, it comes with several drawbacks, including a slow degradation rate, low mechanical strength, and susceptibility to fractures. To address these issues, the present research was done to develop and characterize a novel bioactive glass incorporating gadolinium (Gd) and copper (Cu). The bioactive glass doped with Gd and Cu were synthesized and subjected to characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), and attenuated total reflectance-infrared (ATR-IR) analysis. The bioactive glass, enriched with Gd and Cu, underwent analysis using ATR-IR spectroscopy, XRD, and SEM. ATR-IR revealed characteristic silicate bands, while SEM indicated the presence of particles larger than 4 μm. XRD analysis identified the formation of Na2Ca4(PO4)2SiO4 (Silicorhenatite), Na2Ca2Si3O9 (Combeite), and wollastonite (calcium inosilicate mineral; CaSiO3). The crystalline nature of these compounds contributed to the favorable mechanical properties of the bioactive glass. In summary, the creation of the innovative Gd-Cu-incorporated bioactive glass demonstrates favorable mechanical characteristics, suggesting significant promise for augmenting bone regeneration.

Are We Justified in Modeling Human Exposure to Chlorinated Paraffin Mixtures Using the Average Properties of Congeners and Homologues?

Concern over human exposure to chlorinated paraffin (CP) mixtures keeps increasing. The absence of a comprehensive understanding of how human exposure varies with the physicochemical properties of CP constituents has hindered the ability to determine at what level of aggregation exposure to CPs should be assessed. We answer this question by comparing exposure predicted with either a "complex" method that utilizes isomer-specific properties or "simplified" methods that rely on median properties of congener, homologue, or short-/medium-/long-chain CP groups. Our results demonstrate the wide range of physicochemical properties across CP mixtures and their dependence on molecular structures. Assuming unit emissions in the environment, these variances translate into an extensive disparity in whole-body concentrations predicted for different isomers, spanning ∼11 orders of magnitude. CPs with 13-19 carbons and 6-10 chlorines exhibit the highest human exposure potential, primarily owing to moderate to high hydrophobicity and slow environmental degradation and biotransformation. Far-field exposure is dominant for most CP constituents. Our study underscores that using average properties of congener, homologue, or S/M/LCCP groups yields results that are consistent with those derived from isomer-based modeling, thus offering an efficient and practical framework for future risk assessments and human exposure studies of CPs and other complex chemical mixtures.

Lycopene and β‐carotene thermal degradation kinetics and colour‐antioxidant changes in gac (Momordica cochinchinensis) fruit aril paste

SummaryThis study investigated the impact of heating temperatures (70 °C to 90 °C for up to 14 h) on lycopene and β‐carotene degradation kinetics in gac aril paste. Carotenoids extracted via low‐volume hexane‐assisted ultrasonic extraction revealed a first‐order degradation pattern with high correlation coefficients (0.96–0.97). Lycopene degraded faster at 90 °C (k = 12.05 × 102 h−1) than at 70 °C (5.41 × 102 h−1), while β‐carotene displayed relatively slower degradation. Corresponding half‐life (t1/2) values for lycopene ranged from 5.75 to 12.81 h, while β‐carotene displayed values of 9.48–20.2 h. β‐carotene showed superior thermal stability compared to lycopene across all temperatures. Additionally, colour changes indicated decreased brightness with increasing temperature. The DPPH radical scavenging activity and FRAP values decreased during gac fruit heating. Overall, this study emphasises temperature‐induced declines in lycopene and β‐carotene levels in gac aril paste and offers insights into their degradation kinetics under thermal processing.

Evolution and expression patterns of the neo-sex chromosomes of the crested ibis

Bird sex chromosomes play a unique role in sex-determination, and affect the sexual morphology and behavior of bird species. Core waterbirds, a major clade of birds, share the common characteristics of being sexually monomorphic and having lower levels of inter-sexual conflict, yet their sex chromosome evolution remains poorly understood. Here, by we analyse of a chromosome-level assembly of a female crested ibis (Nipponia nippon), a typical core waterbird. We identify neo-sex chromosomes resulting from fusion of microchromosomes with ancient sex chromosomes. These fusion events likely occurred following the divergence of Threskiornithidae and Ardeidae. The neo-W chromosome of the crested ibis exhibits the characteristics of slow degradation, which is reflected in its retention of abundant gametologous genes. Neo-W chromosome genes display an apparent ovary-biased gene expression, which is largely driven by genes that are retained on the crested ibis W chromosome but lost in other bird species. These results provide new insights into the evolutionary history and expression patterns for the sex chromosomes of bird species.

Intensify Biodegradation Process of Polylactic Acid (PLA) Waste Generated from 3D Printing Activities

Additive manufacturing, or 3D printing, is a key technology driving Industry 4.0. via the formation of three-dimensional objects from a computer-aided design model which can be done through layer-by-layer technique. Polylactic acid (PLA) ranks as one of the most favored materials as a 3D printing filament. Despite its unique properties, PLA took about 12 weeks to biodegrade which is slow degradation leads to an increased rate of plastic pollution in the environment. The aim of this study was to provide an alternative method for bioplastic waste management through biodegradation process using potting mix soil at different incubation temperatures and times. The PLA was designed in coupon shapes and eventually, 3D printed, respectively. Consequently, potting mix soil was prepared in a container and coupon, as all PLA samples were then planted 7 cm from the soil surface. Eventually, PLA samples were subjected to biodegradation process in the soil at 25 °C and 50 °C. Subsequently, each sample was drawn from the soil at different incubation times up to 65 days. The results show that prolong incubation time has resulted in PLA coupon losing weight up to 10.4% and 1.4% for the incubation time of 25 °C and 50 °C, respectively. Meanwhile, the physical structure has deteriorated to powder form and the fragility decreases proportionally as prolonged incubation time. Functional groups analysis showed the functional groups altered after the biodegradation process of PLA and soil. Ergo, this method can be utilized for the community to execute self-degradation of their PLA waste generated even at their own facility.

A review on polylactic acid‐based blends/composites and the role of compatibilizers in biomedical engineering applications

AbstractPoly(lactic acid) (PLA) is one of the most promising biopolymers extensively used in food, packaging, medical and pharmaceutical industries. It is due to favorable physicochemical properties, in‐situ hydrolytic degradation and well‐established processing parameters. However, in medical engineering applications, PLA shows some drawbacks like low cell adhesion, biological inertness, slow degradation rate and high acid inflammation. These shortcomings of pure PLA could be addressed by blending it with other bioresorbable materials and compatibilizers. This review provides comprehensive information on different PLA composites in the field of tissue engineering, implants, injury management and drug delivery systems. The PLA‐based composites are divided into four parts: PLA/polymer, PLA/metal, PLA/ceramic, and PLA/nanoparticles. It also investigates various synthesis process, role of different compatibilizers, in vitro studies and their in vivo applications.Highlights Review the trends of bioresorbable PLA blends/composites. Extensively focused on PLA blend with polymer, metal, ceramic, and nanoparticles. Role of reinforcement and compatibilizer to overcome shortcomings of PLA implant. Highlights advantages, limitations, and properties of different types of PLA implants. Discuss various clinical applications and future of PLA blends/composite scaffolds.

Long‐term outdoor study of an organic photovoltaic module for building integration

AbstractOrganic photovoltaics (OPV) has attracted tremendous attention as a promising alternative to silicon wafer‐based technologies for building integration. While significant progress has been achieved on the power conversion efficiency of OPV technologies, their field stability is rarely studied. This work investigates the field performance and reliability of a large‐area OPV module designed for building integration in tropical Singapore for 4.5 years. The device suffered more than 14% degradation in power at the standard testing conditions from the initial performance, largely due to losses in fill factor (−12% relative). During the monitoring period, it exhibited comparable performance to more conventional silicon PV technologies, with an average specific energy yield of about 4 kWh/kWp/day and an average performance ratio of 0.96. Excellent performance at low light conditions was also observed. However, its field performance was heavily impacted by soiling, which typically led to a 5 to 10% loss in the current output after several months. Further, the device's outdoor performance also showed a three‐stage degradation process, including (1) an initial slow degradation in the first 2 years (about −1%/year), (2) a stable period with negligible performance loss from Years 2 to 3.5, and (3) a rapid degradation in the last year (about −5%/year).

Synergistic effects of photocatalysis-periodate activation system for the degradation of emerging pollutants using GO/MgO nanohybrid

The combination between periodate (PI) activation and photocatalysis processes using heterogeneous catalysts can overcome the slow degradation rates related to photocatalysis and accelerate the degradation of organic pollutants. Thus, a nanohybrid of graphene oxide (GO) and magnesium oxide (MgO) (GO/MgO) was fabricated, characterized, and employed as a photocatalyst and an activator of PI for the degradation of reactive blue-222 (RB-222) dye, sulfamethazine (Sulfonamide antibacterial), and atrazine (Herbicide). Further, the optimization of operating parameters, the stability of the composite, the degradation mechanism, and the effects of water matrices were investigated. The bandgap decreased to 2.6 eV after merging between the GO and MgO, and the separation between charge carriers was improved in the case of the nanohybrid compared to single GO and MgO. The highest degradation percentage of RB-222 dye was achieved under the optimal operating conditions (pH 7, dye concentration of 6.4 mg/L, PI concentration of 1.5 mM, and catalyst dosage of 0.3 g/L) in the presence of light within 120 min. The nanocomposite was reused for five succeeding runs, where the degradation ratios decreased from 97.3% in the first run to 88% in the third run and declined to 81.25% in the fifth run which affirmed the high stability of the catalyst under three succeeding cycles. The degradation mechanism was explored showing that iodate radicals were the main reactive species. The degradation percentages of RB-222 decreased to 85.1% and 67.6% in the case of canal and sea water matrices, respectively. The degradation efficiencies of sulfamethazine and atrazine were 87.5% and 85%, respectively under the optimal conditions. The prepared composite exhibited high degradation performance towards different pollutants which affirmed the applicability of the proposed degradation system for degrading real industrial effluents.

Degradation Potential of Biodegradable Plastics under Laboratory Conditions

Conventional plastics are one of the greatest environmental issues due to their excessive usage and slow degradation. Biodegradable plastics have been introduced as a promising solution to the issue. However, the degradation potential and the best exposure conditions for biodegradable plastics are not well understood in the local context. Therefore, the present study was conducted to evaluate the degradation potential of some commercially available single-use plastics labeled as ―biodegradable‖. Two brands of lunch sheets (LS1 and LS2) made from Polylactic acid (PLA), Polybutylene adipate terephthalate (PBAT), and corn starch, and one waste bag made from Low- density polyethylene (LDPE) and Linear low-density polyethylene (LLDPE) were tested against cellulose filter paper (FP) as a positive control. Degradation was tested using mass loss analysis, biogas production, and FTIR spectrum analysis together with visual analysis. The test materials were subject to different exposures, i.e., placed under seawater, beach sand, freshwater, sand with overlying freshwater, and under direct sunlight for 210 days, and anaerobic exposure for 60 days. LS1 had the highest mass loss of 73.3% in freshwater and the lowest of 9.5% in sunlight exposure. LS2 recorded the highest mass loss of 59.3% in compost exposure and the lowest of 2.9% in sunlight exposure. Waste bags recorded 1.5% as the highest mass loss in the sand with overlying freshwater and the lowest 0.3% under direct sunlight which is the lowest among all four samples. FP has shown the highest and lowest mass loss in composting and direct sunlight exposures at 79.7% and 6.2%. The degradation of FP indicates that the conditions required for biodegradation were present in the exposure environments. Direct sunlight exposure does not show a significant impact on the degradation of any of the test materials. The waste bag does not show considerable degradation under any exposure. The carbon dioxide gas production was 8.76×10-4 mol, 18.49×10-4 mol, and 2.88×10-4 mol in LS1, LS2, and waste bag, respectively. LS1 and LS2 showed visual damages and also changes in the FTIR spectrum. However, waste bags did not show any changes visually or in FTIR spectra. Therefore, it can be concluded that LDPE and LLDPE products did not undergo a detectable degradation though PLA, PBAT, and corn starch products show clear signs of degradation. The study needs to be repeated in situ to better understand the degradation behavior in actual exposure situations. 
 Keywords: Biodegradable plastics, Degradation, Plastic pollution

2D Ruthenium-Chromium Oxide with Rich Grain Boundaries Boosts Acidic Oxygen Evolution Reaction Kinetics.

Ruthenium oxide is currently considered as the promising alternative to Ir-based catalysts employed for proton exchange membrane water electrolyzers but still faces the bottlenecks of limited durability and slow kinetics. Herein, a 2D amorphous/crystalline heterophase ac-Cr0.53Ru0.47O2-δ substitutional solid solution with pervasive grain boundaries (GBs) is developed to accelerate the kinetics of acidic oxygen evolution reaction (OER) and extend the long-term stability simultaneously. The ac-Cr0.53Ru0.47O2-δ shows a super stability with a slow degradation rate and a remarkable mass activity of 455AgRu -1 at 1.6V vs RHE, which is ≈3.6- and 5.9-fold higher than those of synthesized RuO2 and commercial RuO2, respectively. The strong interaction of Cr-O-Ru local units in synergy with the specific 2D structural characteristics of ac-Cr0.53Ru0.47O2-δ dominates its enhanced stability. Meanwhile, high-density GBs and the shortened Ru-O bonds tailored by amorphous/crystalline structure and Cr-O-Ru interaction regulate the adsorption and desorption rates of oxygen intermediates, thus accelerating the overall acidic OER kinetics.

Remaining useful life prediction of bearings using a trend memory attention-based GRU network

Abstract Remaining useful life (RUL) prediction of bearings holds significant importance in enhancing the reliability and durability of rotating machinery. Bearings undergo a gradual degradation process that unfolds over multiple stages. In this paper, a novel framework for forecasting the RUL of bearings is put forward, which includes the construction of a health indicator with a stage division algorithm (SDA) and the estimation of the health indicator using a new trend memory attention-based gated recurrent unit (TMAGRU). The SDA, based on the K-Means++ algorithm and angle recognition algorithm, is introduced to distinguish the degradation stage based on the health indicator. Inspired by the double exponential smoothing technique and attention mechanism, the proposed TMAGRU network effectively incorporates both the historical health information in the slow degradation stage and its trend. Experimental results conducted on IEEE PHM Challenge 2012 dataset and XJTU-SY dataset demonstrate the superior predictive performance of the proposed approach compared to several state-of-the-art predictive networks.

Water transferable, customizable highly ordered honeycomb film from polystyrene foam waste for complex surface patterning in confined space

AbstractThe disposal of plastic foam, mostly composed of polystyrene, poses significant environmental challenges due to its high popularity, slow degradation, and low cost. To address this problem, recycling polystyrene foam waste (PF) has emerged as a promising solution to reduce plastic pollution. This paper presents a novel approach to mass‐produce highly ordered, porous honeycomb‐patterned film (hc‐film) using wasted PF as the raw material. The hc‐film is produced using an improved phase separation (IPS) method that utilizes methanol as a suitable pore inducer and template droplet stabilizer. Methanol provides the hc‐film with customizable features such as pore ordering, size, and separation. The freestanding hc‐film, achieved by adopting a water‐soluble polystyrene sulfonate as a scarified layer, can be transferred and utilized as a flexible mold to pattern various solid substrates with complicated surface morphologies using the pre‐impregnated technique. This study demonstrates the potential of this cost‐effective and efficient approach for various applications, such as super/anti‐wetting surfaces, microelectronics, optical devices, sensors, and nanogenerators.

Enhancing solid-state photochromic performance of Stenhouse Adducts doped in bulk polymers by C3-Symmetric multipolar design

Here, we introduce a C3-symmetric molecular design strategy to develop a brand-new visible-light organic photoswitch, named tri-branched multipolar Stenhouse Adduct (TMSA). After doping TMSA into low glass transition polymers (i.e. thermoplastic urethane, TPU) via simple blending and solution casting, the resultant composite films exploit unique geometric and electronic effects of TMSA to afford markedly-improved photoswitching performance compared to those doped with dipolar donor-acceptor Stenhouse Adduct (DASA) counterparts with suppressed solid state photochromism. Importantly, they display good fatigue resistance over 50 photo-discoloration/thermal-recovery cycles with slow degradation, surpassing those literature-reported composites involving various DASAs (<30 cycles). As revealed by combined experiment and computation studies, the multi-dimensional electronic coupling in multipolar TMSA facilitates the thermal cyclization and non-planar branched structures of TMSA afford large free space in polymers for efficient molecular isomerization, while the promoting effect on TMSA isomerization induced by ester-rich polymer micro-environments is more pronounced relative to DASA counterpart.

Synthesis, crystal structure, thermal stability, and photovoltaic properties of organic-inorganic hybridized copper-based perovskite single crystals modulated by organics

Organic-inorganic hybridized perovskite have excellent photovoltaic properties, especially Pb-based organic-inorganic perovskite polycrystalline thin films based on Pb-based organic-inorganic perovskite have achieved high power conversion efficiency, but the polycrystalline materials have a large number of grain boundaries and defects, which are susceptible to the influence of water and oxygen, leading to structural degradation, poor stability, high toxicity and slow degradation, which are not friendly to the environment. Therefore, in this paper, two copper-based organic-inorganic hybrid perovskite single crystals (C6H9N2)2CuCl4 and (C6H18N2)2Cu2Cl8 were synthesized by using the method of organic modulation, and were investigated by single-crystal X-ray diffraction, powder X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, thermogravimetric analysis, and UV–vis diffuse reflectance spectroscopy. The samples were analyzed in detail for crystal structure, chemical groups, bond characterization, optical and thermal stability. The results show that (C6H9N2)2CuCl4 and (C6H18N2)2Cu2Cl8 single crystals belong to the C2/c space group of the monoclinic crystal system and the P-1 space group of the triclinic crystal system, respectively. The optical band gap of (C6H9N2)2CuCl4 is 2.45 eV, which is stable up to 179 °C, and that of (C6H18N2)2Cu2Cl8 is 2.47 eV, which is stable up to 163 °C. The thermal stability of the crystals can be regulated by changing the organic cation in the A-site, but the optical band gap of the crystals cannot be regulated significantly.

Enhanced lignin degradation by Irpex lacteus through expanded sterilization further improved the fermentation quality and microbial community during the silage preservation process

Traditional autoclaving, slow degradation rate and preservation of biomass treated by fungi are the main factors restricting biological treatment. In our previous studies, strains with high efficiency and selective lignin degradation ability were obtained. To further solve the limiting factors of biological treatment, this paper proposed a composite treatment technology, which could replace autoclaves for fungal treatment and improve the preservation and utilization of fungal-pretreated straw. The autoclaved and expanded buckwheat straw were, respectively, degraded by Irpex lacteus for 14 days (CIL, EIL), followed by ensiling of raw materials (CK) and biodegraded straw of CIL and EIL samples with Lactobacillus plantarum for different days, respectively (CP, CIP, EIP). An expansion led to lactic acid bacteria, mold, and yeast of the samples below the detection line, and aerobic bacteria was significantly reduced, indicating a positive sterilization effect. Expansion before I. lacteus significantly enhanced lignin selective degradation by about 6%, and the absolute content of natural detergent solute was about 5% higher than that of the CIL. Moreover, EIL decreased pH by producing higher organic acids. The combination treatment created favorable conditions for ensiling. During ensiling, EIP silage produced high lactic acid about 26.83 g/kg DM and the highest acetic acid about 22.35 g/kg DM, and the pH value could be stable at 4.50. Expansion before I. lacteus optimized the microbial community for ensiling, resulting in EIP silage co-dominated by Lactobacillus, Pediococcus and Weissella, whereas only Lactobacillus was always dominant in CP and CIP silage. Clavispora gradually replaced Irpex in EIP silage, which potentially promoted lactic acid bacteria growth and acetic acid production. In vitro gas production (IVGP) in EIL was increased by 30% relative to CK and was higher than 24% in CIL. The role of expansion was more significant after ensiling, the IVGP in EIP was increased by 22% relative to CP, while that in CIP silage was only increased by 9%. Silage of fungal-treated samples reduced methane emissions by 28% to 31%. The study demonstrated that expansion provides advantages for fungal colonization and delignification, and further improves the microbial community and fermentation quality for silage, enhancing the nutrition and utilization value. This has practical application value for scaling up biological treatment and preserving the fungal-treated lignocellulose.Graphical

Synergistic transformation: Kinetic and thermodynamic evaluation of co-pyrolysis for low-rank bituminous coal and polyurethane foam waste

Co-pyrolysis is regarded as a sustainable and ecologically friendly method of improving waste management, pollution control, and renewable energy security. This investigation reports a thermo-kinetic study of low-rank coal-polyurethane foam waste (C-PU) blends through co-pyrolysis and was characterized using a number of techniques such as CHNS-O, GCV, and FTIR. The thermal degradation behavior of C-PU blends during co-pyrolysis via TGA is studied, whereas the degradation process happens in three stages i.e. moisture, devolatilization, and slow degradation of the char in the temperature ranges viz. (25 –140 °C), (140 – 580 °C), and (580 – 900 °C) respectively. Synergistic effects observed may improve product qualities compared to those from separate pyrolysis. The presence of synergistic effects during co-pyrolysis was demonstrated by the positive variation in WL% and DTGmax values. The Coats-Redfern integral method was utilized to investigate the thermo-kinetic parameters of C-PU blends through twelve (12) reaction mechanism models. The activation energy (Ea) for 100C and 100PU was 60.08 kJ/mol and 100.8 kJ/mol via F2 and F3 models, although the optimum blend (50 C-50PU) showed 67.01 kJ/mol and 26.74 kJ/mol via F2 and D3 model in the first and second stage. Thermodynamic characteristics i.e. (∆G) and (∆H) displayed positive values, while (∆S) for each C–PU blend was negative, but the best blend further lowered it. It was found that the fuels could be ranked in the following order 100PU> 50 C-50PU> 100 C based on mean reactivity and pyrolysis factor. The co-pyrolysis of polyurethane foam waste with low-rank coal to develop alternative energy sources has been proposed as a potential method and is critical for designing an effective large-scale reactor system thus understanding the solid-state co-pyrolytic kinetics.

Determination of bisphenols in beeswax based on sugaring out–assisted liquid–liquid extraction: Method development and application in survey, recycling and degradation studies

The methodology of sugaring out–assisted liquid–liquid extraction (SULLE) coupled with high-performance liquid chromatography–fluorescence detection was devised for quantifying bisphenol A (BPA) and bisphenol B (BPB) in beeswax. The effectiveness of SULLE was methodically explored and proved superior to the salting out–assisted liquid–liquid extraction approach for beeswax sample preparation. The analytical performance underwent comprehensive validation, revealing detection limits of 10 μg/kg for BPA and 20 μg/kg for BPB. The method developed was employed to analyse commercial beeswax (n = 15), beeswax foundation (n = 15) and wild-build comb wax (n = 26) samples. The analysis revealed BPA presence in four commercial beeswax samples and three beeswax foundation samples, with the highest detected residue content being 88 ± 7 μg/kg. For BPB, two beeswax foundation samples were positive, with concentrations below the limits of quantification and 85 ± 4 μg/kg, respectively. No bisphenols were detected in wild-build comb wax. Furthermore, the bisphenol removal efficacy of two recycling methods—boiling in water and methanol extraction—was assessed. The findings indicated that after four recycling cycles using water boiling, 9.6% of BPA and 29.2% of BPB remained in the beeswax. Whereas methanol extraction resulted in approximately 7% residual after one recycling process. A long-term study over 210 days revealed the slow degradation of bisphenols in comb beeswax. This degradation fitted well with a first-order model, indicating half-lives (DT50) of 139 days for BPA and 151 days for BPB, respectively. This research provides the first report on bisphenol contamination in beeswax. The low removal rate during the recycling process and the gradual degradation in beeswax underscore the significance of bisphenol contamination and migration in bee hives along with their potential risk to pollinators warranting concern. Furthermore, the developed SULLE method shows promise in preparing beeswax samples to analyse other analytes.

Basalt fibre degradation in seawater and consequences for long term composite reinforcement

Basalt fibres are increasingly employed as reinforcements in marine composites, but their behaviour in natural marine environments is underexplored. This study investigates basalt fibre ageing in renewed natural seawater at 15 °C and 40 °C. After one month in seawater at 15 °C and 40 °C, tensile strength dropped, stabilizing at approximately −40% and −60%, respectively. This rapid initial property decline, followed by slower degradation, is attributed to an altered surface layer on the fibres. Initially causing significant property loss, this layer then plays a protective role, preserving the fibre core. The impact on basalt/epoxy composites exposed to 7.5 years of seawater was less severe, with a 20% loss at 40 °C, demonstrating the protective function of the matrix. This study suggests that basalt fibres undergo rapid, then stable, property degradation in water, but remain suitable for use as epoxy matrix composite reinforcements, thanks to the protective role of the resin.

Double-function synergistic treatment system: Mask-biochar package for methylene blue adsorption and high-quality bioproducts recovery via pyrolysis in wastewater treatment and fuel production

Waste disposable masks cause serious environmental pollution due to their slow degradation. This study investigated a simple and efficient method to recycle masks for high-value additional utilization. Polypropylene-based waste masks were dismantled and combined with Enteromorpha clathrate biochar (AC) to produce mask-biochar packages (M-AC), which were applied to wastewater (containing methylene blue) treatment. The results showed that compared with AC alone, the removal rate of MB solution by mask-biochar packages (M-AC) increased by 18.50 %. Then, the used mask-biochar packages (M-AC) were pyrolyzed at 550 °C to obtain hydrocarbon-rich bio-oil and composite biochar (MAC). Compared to MAC alone, the mask-biochar package (M-MAC) increased the removal rate of MB by 10.16 %. The composite biochar has achieved a high adsorption capacity of 820.925 mg·g−1 without any activator and acid washing process. The hydrocarbon content is 55.31 % which makes it a hydrocarbon-rich bio-oil. This study provided effective experimental support for the combined use of biomass and mask for waste treatment and for the production of biochar.

Impact of Polylactic Acid Fibers in Cellulose Nonwoven Mulch Blends on Biodegradability and Performance-An Open Field Study.

The performance and degradation of nonwoven mulches made from viscose, jute, hemp fibers, and their blends with PLA fibers, subjected to field conditions, are investigated. This research explores the possible substitution of traditional agricultural polyethylene mulching agro foil with environmentally friendly biodegradable nonwoven mulches produced from blends of jute, hemp, and viscose fibers along with PLA fibers. The nonwoven mulches underwent a ten-month exposure to field conditions, showing varied degradation. The jute and hemp nonwoven mulches degraded completely within the test period, whereas their blends with PLA fibers exhibited slowed degradation. This study indicated that PLA fibers in blends with jute, hemp, and viscose mulches slowed degradation, impacting their structural integrity and tensile properties. The tensile properties of nonwoven mulches blended with 20% of PLA fibers increased the breaking forces after field exposure. Observations on structural changes through microscopy highlighted the structure maintenance in jute and hemp blends due to the non-degraded PLA fibers, contrasting the complete degradation of 100% jute and hemp mulches. A microscopic analysis revealed alterations in the fiber structure and density changes, particularly in viscose mulches and their blends with PLA fibers. Soil temperature variations were observed under different mulches; e.g., agro foil consistently exhibited higher temperatures compared to nonwoven mulches. Notably, the hemp and jute/PLA blend mulches showed slightly elevated temperatures, while the viscose-based mulches consistently revealed the lowest temperatures. Regarding soil moisture, the nonwoven mulches generally maintained higher moisture levels compared to the control field and agro foil from June to October. These findings suggest that nonwoven mulches effectively preserved soil moisture during critical growth periods, potentially positively impacting plant growth. The weed suppression capabilities varied among mulches, with hemp mulch initially displaying the lowest suppression ability in the first six months. The addition of 20% of PLA fibers in mulch blends with viscose, jute, and hemp notably improved the weed control capabilities. Understanding the impacts of field conditions on newly produced nonwoven mulches is crucial for optimizing mulch selection in agricultural practices to enhance soil conditions and weed management.