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Correlations between the mechanical properties and surface scratch resistance of polylactic acid (PLA) are investigated via tensile and scratch tests on samples after degradation in soil for various times. The results show that the tensile yield strength of PLA is inversely proportional to the natural logarithm of the degradation time, and the scratch resistance and fracture toughness of PLA and the temperature rise near the indenter all increase and then decrease. The surface crystallinity of PLA also increases and then decreases, indicating that it and the scratch resistance are closely related. These findings provide useful information about how PLA behaves under degradation conditions. (c) 2025 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC) license (https://creativecommons.org/licenses/by-nc/4.0/).

期刊论文 2025-12-01 DOI: 10.1063/5.0252651 ISSN: 1672-6030

This study focuses on bio-based natural fiber-reinforced polymer composites (NFRPCs). In this work, bio-polybutylene succinate (bio-PBS) reinforced with hemp fibers (HF) varying at 10 wt%, 20 wt%, and 30 wt% were developed via microwave-assisted compression moulding (MACM) technique. The mechanical properties, crystalline properties, dynamic mechanical analysis, and soil degradation behaviour of these composites were analysed. The study demonstrated that composites with 30 wt% hemp fiber content exhibited the most optimal mechanical properties, with crystallinity increasing by 22%. These composites achieved the highest storage modulus of 13,349 MPa, while their loss modulus was found to be 110% higher compared to neat bio-PBS. Additionally, soil burial experiments revealed that the 30 wt% HF/bio-PBS composites underwent the greatest weight loss after 60 days of soil exposure, indicating superior biodegradability compared to the pure bio-PBS matrix. The work further concluded that hemp fiber-reinforced bio-PBS composites showcased improved mechanical performance, crystallinity, biodegradability, and processing characteristics, surpassing other bio-composite alternatives.

期刊论文 2025-05-01 DOI: 10.1007/s12221-025-00944-x ISSN: 1229-9197

Bamboo charcoal (BC) was utilized as a modifier to functionalize poly (L-lactide-co-epsilon-caprolactone) (PLCL) in this research. Five types of BC/PLCL composite films with varying BC content (0.5 wt%, 1.0 wt%, 1.5 wt%, 2.0 wt%, and 2.5 wt%) were fabricated and subjected to degradation studies in soil. The degradation performance of these composite films was assessed by analyzing changes in apparent morphology, micromorphology, mass loss, molecular weight, and mechanical properties after 20, 40, 60, and 80 days of degradation. Results indicated a gradual increase in the degradation level of PLCL over time, accompanied by a decrease in elongation at break from 273.5 % to 12.01 %. The incorporation of BC was found to decelerate the degradation of PLCL, leading to a delayed degradation process as the proportion of BC increased.

期刊论文 2025-04-29 DOI: 10.1680/jgrma.24.00141 ISSN: 2049-1220

Lake Van is T & uuml;rkiye's largest lake, and within it lies Akdamar, a small seven-hectare island. In 2008, eight feral European rabbits were introduced to the island to attract tourists. With no natural predators, their population had increased to 3,000 by 2016, causing severe ecological damage, destroying almond trees, accelerating soil erosion, and damaging historical buildings through burrowing. In response, local authorities launched a management programme from 2016 to 2017, removing 1,500 rabbits through physical control methods such as live trapping, net trapping, and night spotlighting. However, funding shortages halted further efforts, and the population surged to an estimated 4,000-5,000 by 2023. The rabbits now occupy the entire island, degrading vegetation, diminishing ecosystem services, and threatening tourism. According to the assessment conducted in this study, the situation is classified as causing major ecological impacts under the Environmental Impact Classification for Alien Taxa and minor cultural effects under the Socio-Economic Impact Classification of Alien Taxa. Therefore, urgent, long-term management solutions are essential to prevent further degradation, with public awareness campaigns, community involvement, and education can help reduce human-mediated spread and promote responsible behaviour. Coupled with sustainable, effective management strategies, these efforts are vital to preserving the island's ecosystem and cultural heritage.

期刊论文 2025-04-03 DOI: 10.1080/09397140.2025.2491145 ISSN: 0939-7140

Plant-based macromolecules such as lignocellulosic fibers are one of the promising bio-resources to be utilized as reinforcement for developing sustainable composites. However, due to their hydrophilic nature and weak interfacial bonding with polymer matrices, these fibers are mostly incompatible with biopolymers. The current research endeavor explores the novel eco-friendly oxalic acid (C2H2O4. 2H2O) treatment of sisal fibers (SF) with different concentrations (2, 5, and 8 % (w:v)) and exposure duration (4, 8, and 12 h). Optimum treatment conditions were achieved through the single fiber strength testing of SFs. The tensile strength of the treated fiber with 8 % concentration and 12 h exposure duration (TSF/8/12) increased by approximately 60 % compared to untreated SF. Fourier transform infrared spectroscopy (FTIR), morphological observation, X-ray diffraction (XRD), and thermogravimetric analysis (TGA) of untreated and treated fibers confirmed that TSF/8/12 has better mechanical and crystallinity behavior than its counterparts. The thermal stability and maximum degradation temperature of the TSF/8/12 are 232 degrees C and 357 degrees C. Sustainable composites were fabricated by introducing the treated SFs (30 wt%) as reinforcement in a bio-based poly (butylene succinate) (bio PBS) matrix. The experimental evaluation of mechanical properties, thermal degradation behavior, and water absorption established that treated fiber-reinforced biocomposites (bio PBS/TSF/8/12) have strong interfacial bonding between constituents that resulted in better thermal stability and decreased water uptake than untreated sisal fiber (USF)based composites (bio PBS/USF). The results of the soil degradation confirmed that SFs expedite the rate of degradation of composites due to the increased availability of hydroxyl groups.

期刊论文 2025-03-01 DOI: 10.1016/j.ijbiomac.2025.139507 ISSN: 0141-8130

Background . On the territory of Ukraine, where large-scale hostilities are taking place, industrial production and developed transport infrastructure are concentrated, in particular, every tenth enterprise has an increased (1st or 2nd) hazard class. Arable fields suffered no less damage from shelling and mining, which negatively affects food security in the world. The degree of ecological hazard of the territory where hostilities took place is determined primarily by the level of surface concentrations of pollutants entering the natural environment. Concentrations, as well as the range and area of dispersion of pollutants depend on the parameters of the explosion, the height of the explosion product clouds, and meteorological conditions. Methods . For war-affected areas, mechanisms for assessing the degree of mechanical damage to soils and dust from a gas-dust cloud into the environment were proposed based on methods used at mining enterprises to analyze environmental hazards. Results . The studies were carried out in the field, where ca.1000 craters of various diameters were identified. The main parameters of the explosion were estimated based on the morphological shapes of the craters: the volume of displaced (or destroyed) soil, the mass of aerosol and dust that entered the atmosphere, the width and height of the pile-the scattering of soil from the centre of the explosion. The height of the gas-dust cloud from large explosions was calculated, which is extremely important for modelling the dynamics of solid particles in the cloud and solving problems of regional pollution transportation. A sequential algorithm was developed for assessing the destruction and damage to soils and the release of aerosol and dust into the atmosphere, which is formed during ground explosions. Conclusions . An algorithm for calculating the degree of soil damage and dust ingress into the atmosphere from artillery weapons of various calibers has been proposed. Calculations of the height of the gas-dust cloud from large explosions and the scattering of earth from the craterhave been obtained. The cumulative effect of soil damage and atmospheric pollution bysubstances from explosion products per day, month and year has been estimated. The results of comparing the damage caused to soils and emissions of harmful substances into the atmosphere as a result of the war are comparable in scale to the operation of an average quarry in Ukraine for a year. Given the scale of the battle lines environmental pollution would have catastrophic consequences.

期刊论文 2025-01-01 DOI: 10.17721/1728-2713.108.05 ISSN: 1728-2713

In the reported work, coarse wool fibre was mixed with natural rubber (NR) at equal proportion in two roll mixing machine and subsequently wool- NR composite was prepared using a compression moulding machine. The physico-mechanical properties of the developed composites such as tensile strength, areal density, hardness, thermal stability, water diffusion, moisture absorption, etc were analyzed. The composites were further characterized for its surface morphology, curing characteristics, accelerated aging properties, ultraviolet resistance,, and Fourier Transform Infrared Spectroscopy (FTIR). The results were compared with bare vulcanized rubber (VR). It is inferred that, while adding wool in the NR matrix, the time taken for the vulcanization got considerably reduced. Though the wool - NR composite showed reduction in tensile strength in comparison with VR, the tear strength, hardness, areal density, and Young's modulus were found to be improved. Thermal analysis of the composite depicted that the incorporation of wool fibre caused an improvement in the thermal stability of the composite in comparison with the vulcanized rubber.

期刊论文 2024-12-15 DOI: 10.1016/j.indcrop.2024.119727 ISSN: 0926-6690

Polyoxalate, a novel intrinsically hydrolysable polyester, garners significant interest for its high costeffectiveness and versatility. However, concerns persist regarding its durability in practical applications. This study integrates bio-based poly(butylene furanoate) (PBF), which possesses remarkable barrier performance, into the poly(butylene oxalate) (PBOx) framework to synthesize poly(butylene oxalate-co-furanoate) (PBOF) with tunable degradation rates. The influence of incorporating BF units on thermal, crystalline, mechanical, and barrier properties was systematically analyzed. Results demonstrated the addition of BF units dramatically improved the balance between degradation and physical properties. Laboratory degradation experiments indicated that PBOF possessed significant degradation effects. Among them, PBOF-41 (with 41 % molar furanoate) decreased in weight by 20 % in freshwater, 70 % in an enzyme solution, and 8 % in artificial seawater within 30 days. After 28 days of degradation in soil, the residual weight was reduced to 80 % of its initial weight. Theoretical calculations and experiments have clarified the enhancement of the Gibbs free energy and energy barrier of the hydrolysis reaction by the BF unit. In summary, PBOF copolyesters have excellent gas barrier performance, adjustable thermal properties, well-balanced mechanical properties, and degradability, making them highly promising for sustainable plastic products.

期刊论文 2024-12-05 DOI: 10.1016/j.jhazmat.2024.135997 ISSN: 0304-3894

Globally, approximately 2.12 billion tons of waste are annually disposed of, with laboratories significantly contributing across diverse waste streams. Effective waste management strategies are crucial to mitigate environmental impact and promote sustainability within scientific communities. This study addresses the challenges by introducing a novel method that transforms laboratory media waste into a valuable biopolymer named Agastic. The process involves repurposing agar extracted from bulk laboratory waste, blending it with bio-based plasticizers to produce Agastic sheets exhibiting mechanical properties comparable to traditional bioplastics. Using response surface methodology (RSM) and central composite design (CCD), optimal concentrations of agar (1.5-2.5% w/v), glycerol (0.25-1% v/v), and ethanolamine (0.5-1.5% v/v) were determined. Predictions from Design Expert software indicated impressive tensile strength up to 14.31 MPa for AGA-1 and elongation at break up to 52% for AGA-2. Fourier Transform Infrared Spectroscopy (FTIR) analysis confirmed agarose structural features in AGA-1 and AGA-2. Thermogravimetric analysis (TGA) showed polysaccharide-related breakdown between 38 degrees C and 280 degrees C in AGA-1, peaking at 299.36 degrees C; AGA-2 exhibited diverse thermal decomposition up to 765 degrees C, suggesting their biodegradable potential in packaging applications. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) analysis confirmed nontoxic nature of Agastic and preserved morphological integrity in both samples. Soil degradation studies revealed AGA-1 and AGA-2 losing 71.31% and 70.88% of weight, respectively, over 15 days. This innovation provides a sustainable pathway to repurpose laboratory waste into eco-friendly bioplastics, particularly suitable for moisture-sensitive packaging such as nursery applications. These findings underscore Agastic films' promise as environmentally friendly alternatives to traditional plastics, supporting circular bioeconomy principles and significantly reducing ecological impacts associated with plastic waste.

期刊论文 2024-09-28 DOI: 10.1177/0958305X241282606 ISSN: 0958-305X

This study quantified the immediate impact of soil deformation caused by agricultural vehicle traffic on the anisotropy of the topsoil pore system and gas transport properties (air permeability, gas diffusivity). A field experiment was conducted with five repeated passes of a two -axle self-propelled agricultural vehicle (wheel load 8 Mg, tyre size: 1050/50 R32, tyre inflation pressure: 100 kPa) on an arable clay soil (crop at the time of the experiment: grass ley) in north-western Switzerland. Undisturbed cylindrical soil cores were collected in nonwheeled areas, at the edge of the wheel rut (i.e., at 0.5 m lateral distance from the centre of the wheel track), and at the centre line of the wheel track. The soil cores (0.1 m diameter, 0.06 m in height) were taken in two directions (vertical and horizontal) in the topsoil (0.1 m depth). Air -filled porosity ( epsilon a ), air permeability ( k a ) and relative gas diffusivity ( D p / D 0 ) were measured at three matric potentials (corresponding to p F 1.5, 2.0, and 2.5, respectively). The vehicle -induced deformation resulted in significantly reduced epsilon a , k a , D p / D 0 in the topsoil. Air permeability was highly anisotropic in non -wheeled soil, with higher k a in vertical direction. Compaction mainly affected macropores and hence k a at the wet end ( p F 1.5), decreased the vertical k a more than the horizontal k a , and consequently, k a became less anisotropic due to compaction. This effect was stronger under the edge of the wheel rut than in the centre of the wheel rut. The anisotropy of D p / D 0 was little affected by the vehicle -induced soil deformation. Our results show that soil deformation due to vehicle traffic not only decreases the gas transport capacity of soil but also changes the anisotropy of air permeability, with consequences on soil aeration and soil -atmosphere gas exchange.

期刊论文 2024-09-01 DOI: 10.1016/j.still.2024.106126 ISSN: 0167-1987
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