There has been a growing interest in controlled low strength material CLSM due to its engineering features, such as self-leveling and early strength development, as well as it potential for utilizing industrial waste. Still, the dynamic properties on CLSM are rarely studied. This study evaluates the feasibility of red mud as a partial aggregate replacement in foamed-lightweight CLSM, incorporating high-carbon fly ash and preformed foam. We varied both the red mud contents RMc and foam volume ratio FVR within the mixtures and examined their impact on unconfined compressive strength and dynamic properties including shear modulus G and damping ratio D. The results reveal that the red mud enhances foam stability, leading to more uniform pore structures and increased porosity, which reduces bulk densities. Despite higher porosity, red mud serves as a strong alkaline activator, enhancing geopolymer reactions of high-carbon fly ash and thereby increasing both compressive strength and initial shear modulus G0. Interestingly, increasing FVR had minimal impact on the D, while higher RMcnotably increased D, highlighting its distinct role in energy dissipation. The red mud-incorporated foamed CLSM exhibits strain-dependent normalized shear modulus G/G0 comparable to that of gravel, while its D is 40-100 % higher than gravel or gravelly soil at shear strain of 1.10-5, which corresponds to typical traffic-induced vibration levels. Moreover, theoretical volumetric-gravimetric relationships are introduced to account for the combined effects of FVR and RMcon CLSM behavior. These findings demonstrate that the red mud included foamed CLSM can be utilized as advanced structural backfill material capable of effectively mitigating the vibrations induced by traffic, low-amplitude seismic events, and mechanical sources.

The development of biodegradable and recyclable food packaging materials derived from biomass is a promising solution to mitigate resource depletion and minimize ecological contamination. In this study, lignin nanoparticles (LNPs) were effectively produced from bamboo powder using an eco-friendly recyclable acid hydrotrope (RAH) strategy. A sustainable CA/LNPs nanocomposite film was then designed by incorporating these LNPs into a casein (CA) matrix. The LNPs served as nucleation templates, inducing ordered hydrogen bonding and close packing of the CA chains. The addition of 5 wt% LNPs significantly enhanced the mechanical properties of the film, with tensile strength enhanced to 21.42 MPa (219.7 % improvement) and elastic modulus rising to 354.88 MPa (220.3 % enhancement) compared to pure CA film. Notably, the resultant CA/LNPs nanocomposite film exhibited recyclable recasting characteristics, maintaining a reasonable mechanical strength even after three recasting cycles. The incorporation of LNPs also decreased the water solubility of the pure CA film from 31.65 % to 24.81 % indicating some interactions are taking place, while endowing the film with superior UV-blocking ability, achieving nearly complete absorption in the 200-400 nm range. Moreover, the inherent properties of LNPs imparted improved antibacterial and antioxidant activities to the CA/LNPs nanocomposite film. Owing to its comprehensive properties, the CA/LNPs nanocomposite film effectively extended the storage life of strawberries. A soil burial degradation test confirmed over 100 % mass loss within 45 days, highlighting excellent degradability of the films. Therefore, the simple extraction of LNPs and the easily recovery of p-TsOH provide significant promise and feasibility for extending the developed methodologies in this work to rapidly promote the produced films in fields such as degradable and packaging materials.

Salinity stress is one of the most detrimental abiotic factors affecting plant development, harming vast swaths of agricultural land worldwide. Silicon is one element that is obviously crucial for the production and health of plants. With the advent of nanotechnology in agricultural sciences, the application of silicon oxide nanoparticles (SiO-NPs) presents a viable strategy to enhance sustainable crop production. The aim of this study was to assess the beneficial effects of SiO-NPs on the morpho-physio-biochemical parameters of rice (Oryza sativa L., variety: DRR Dhan 73) under both normal and saline conditions. To create salt stress during transplanting, 50 mM NaCl was injected through the soil. 200 mM SiO-NPs were sprayed on the leaves 25 days after sowing (DAS). It was evident that salt stress significantly hindered rice growth because of the reductions in shot length (41 %), root length (38 %), shot fresh mass (40 %), root fresh mass (47 %), shoot dry mass (48 %), and root dry mass (39 %), when compared to controls. Together with this growth inhibition, elevated oxidative stress markers including a 78 % increase in malondialdehyde (MDA) and a 67 % increase in hydrogen peroxide (H2O2) indicating enhanced lipid peroxidation were noted. Increasing the chlorophyll content (14 %), photosynthetic rate (11 %), protein levels, total free amino acids (TFAA; 13 %), and total soluble sugars (TSS; 11 %), all help to boost nitrogen (N; 16 %), phosphorous (P; 14 %), potassium (K; 12 %), and vital nutrients. The adverse effects of salt stress were significantly reduced by exogenous application of SiO-NPs. Additionally; SiO-NPs dramatically raised the activity of important antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT), improving the plant's ability to scavenge reactive oxygen species (ROS) and thereby lowering oxidative damage brought on by salt. This study highlights SiO-NPs' potential to develop sustainable farming practices and provides significant new insights into how they enhance plant resilience to salinity, particularly in salt-affected regions worldwide.

Researchers have tried hard to study the toxic effects of single pollutants like certain antibiotics and nanoplastic particles on plants. But we still know little about how these pollutants interact when they're together in the environment, and what combined toxic effects they have on plants. This study assessed the toxic effects of polystyrene nanoplastics (PS-NPs) and ciprofloxacin (CIP), both individually and in combination, on soybean (Glycine max L.) seedlings by various concentration gradients treatments of PS-NPs (0, 10, 100 mg/L) and CIP (0, 10 mg/L). The results indicated that high concentrations of PS-NPs significantly impeded soybean seedling growth, as evidenced by reductions in root length, plant height, and leaf area. CIP predominantly affected the physiological functions of leaves, resulting in a decrease in chlorophyll content. The combined exposure demonstrated synergistic effects, further intensifying the adverse impacts on the growth and physiological functions of soybean seedlings. Metabolomic analyses indicated that single and combined exposures markedly altered the metabolite expression profiles in soybean leaves, particularly related to amino acid and antioxidant defense metabolic pathways. These results indicate the comprehensive effects of NPs with antibiotics on plants and provide novel insights into toxic mechanisms.

Nanoplastics (NPs) and zinc (Zn), both widespread in soil environments, present considerable risks to soil biota. While NPs persist environmentally and act as vectors for heavy metals like Zn, their combined toxicity, especially in soil invertebrates, remains poorly understood. This study evaluates the individual and combined effects of Zn and NPs on earthworm coelomocytes and explores their interactions with Cu/Zn-superoxide dismutase (SOD), an antioxidant enzyme. Molecular docking revealed that NPs bind near the active site of SOD through pi-cation interactions with lysine residues, further stabilized by neighboring hydrophobic amino acids. Viability assays indicated that NPs alone (20 mg/L) had negligible impact (94.54 %, p > 0.05), Zn alone (300 mg/L) reduced viability to 80.02 %, while co-exposure reduced it further to 73.16 %. Elevated levels of reactive oxygen species (ROS) and malondialdehyde (MDA) levels were elevated to 186 % and 173 % under co-exposure, alongside greater antioxidant enzyme disruption, point to synergistic toxicity. Dynamic light scattering and zeta potential (From -13 to -7 mV) analyses revealed larger particle sizes in the combined system, indicative of enhanced protein interactions. Conformational changes in SOD, such as alpha-helix loss and altered fluorescence, further support structural disruption. These findings demonstrate that co-exposure to NPs and Zn intensifies cellular and protein-level toxicity via integrated physical and biochemical mechanisms, providing critical insight into the ecological risks posed by such co-contaminants in soil environments.

Climate change is transforming the ice-free areas of Antarctica, leading to rapid changes in terrestrial ecosystems. These areas represent <0.5% of the continent and coincide with the most anthropogenically pressured sites, where the human footprint is a source of contamination. Simultaneously, these are the locations where permafrost can be found, not being clear what might be the consequences following its degradation regarding trace element remobilisation. This raises the need for a better understanding of the natural geochemical values of Antarctic soils as well as the extent of human impact in the surroundings of scientific research stations. Permafrost thaw in the Western Antarctic Peninsula region and in the McMurdo Dry Valleys is the most likely to contribute to the remobilisation of toxic trace elements, whether as the result of anthropogenic contamination or due to the degradation of massive buried ice and ice-cemented permafrost. Site-specific locations across Antarctica, with abandoned infrastructure, also deserve attention by continuing to be a source of trace elements that later can be released, posing a threat to the environment. This comprehensive summary of trace element concentrations across the continent's soils enables the geographical systematisation of published results for a better comparison of the literature data. This review also includes the used analytical techniques and methods for trace element dissolution, important factors when reporting low concentrations. A new perspective in environmental monitoring is needed to investigate if trace element remobilisation upon permafrost thaw might be a tangible consequence of climate change.

Subway subgrades typically consist of alternating deposits of soil layers with significantly different physical and mechanical properties. However, the overall dynamic characteristics and the evolution of micro-porous structures in stratified soils is often overlooked in current studies. In this study, cyclic triaxial tests were conducted on homogeneous sand, silt and stratified soils with different height ratios, and nuclear magnetic resonance (NMR) was used to investigate the changes in pore structure and moisture content. The dynamic behavior and macroscopic deformation mechanisms were systematically investigated in terms of stress amplitude, confining pressure, and layer height ratio (the ratio of sand to silt height). The results show that as the sand height ratio increases, the axial strain and pore water pressure first increase and then decrease, reaching the maximum when h(Sand): h(Silt) = 2:1. When the confining pressure is 100 kPa, the axial strain of h(Sand): h(Silt) = 2:1 is 181.08 % higher than that of silt. Under the dynamic loading, the stratified soils form a dense skeletal structure near the stratification plane, which hinders the flow and dissipation of pore water, so that the pore water agglomeration phenomenon occurs near the stratification plane, which aggravates the accumulation of residual pore pressure and reduces the deformation resistance. However, when h(Sand): h(Silt) = 4:1, the influence of the stratification planes is significantly reduced, and the deformation characteristics approach homogeneity. This study reveals the dynamic characteristics of stratified soils by comparing and analysing homogeneous samples.

Agricultural nanotechnology has emerged as an effective tool for enhancing crop yield and agricultural productivity amid the growing world population. Over the past ten years, application of nanoparticles (NPs) as nano fertilizers or bio-stimulants has been grown to enhance the morphological and biochemical parameters of various crops. The growth and development of edible crop is affected by soil iron deficiency, particularly in agricultural land that lacks sustainable management practices. This review evaluates effect of Iron oxide nanoparticles (IONPs) on agricultural plant growth. Iron is a micro-nutrient, which is essential for plants. The uptake of IONPs in plant mainly depends upon the exposure method i.e. foliar spray through leaves, soil treatment through roots and seed priming through pre-soaking of seeds. Their impact can be positive or negative depending on the variable conditions in the environment, application method, duration of exposure, concentration and size of IONPs. Various studies have shown that IONPs had affected the growth, seed germination, yield and quality of plants. Low concentration of IONPs resulted in increased rate of seed germination, plant biomass and photosynthetic pigments while at high concentration it causes toxicity by generating hydroxyl radicals leading to plant damage. This review provides an overview of IONPs effect on plants, seed germination, plant growth and morphology, yield and quality, their application in different plants, photosynthesis and toxicity.

Knowledge Gap: The aggregation of clay minerals-layered silicate nanoparticles-strongly impacts fluid flow, solute migration, and solid mechanics in soils, sediments, and sedimentary rocks. Experimental and computational characterization of clay aggregation is inhibited by the delicate water-mediated nature of clay colloidal interactions and by the range of spatial scales involved, from 1 nm thick platelets to flocs with dimensions up to micrometers or more. Simulations: Using a new coarse-grained molecular dynamics (CGMD) approach, we predicted the microstructure, dynamics, and rheology of hydrated smectite (more precisely, montmorillonite) clay gels containing up to 2,000 clay platelets on length scales up to 0.1 mu m. Simulations investigated the impact of simulation time, platelet diameters (6 to 25 nm), and the ratio of Na to Ca exchangeable cations on the assembly of tactoids (i.e., stacks of parallel clay platelets) and larger aggregates (i.e., assemblages of tactoids). We analyzed structural features including tactoid size and size distribution, basal spacing, counterion distribution in the electrical double layer, clay association modes, and the rheological properties of smectite gels. Findings: Our results demonstrate new potential to characterize and understand clay aggregation in dilute suspensions and gels on a scale of thousands of particles with explicit representation of counterion clouds and with accuracy approaching that of all-atom molecular dynamics (MD) simulations. For example, our simulations predict the strong impact of Na/Ca ratio on clay tactoid formation and the shear-thinning rheology of clay gels.

Investigating the toxicological effects of aged nanoplastics (NPs) in soil is critical, as UV irradiation may exacerbate their ecological toxicity by altering surface properties and enhancing interactions with the soil. Here, we investigated the effects of different concentrations of pristine and aged polystyrene (PS) and carboxylpolystyrene (PSC) NPs on lettuce and soil properties. Both pristine and aged NPs inhibited pigment synthesis and lettuce growth. The maximum growth inhibition rates of leaf (root) biomass were 10.2 % (23.4 %) and 32.7 % (45.3 %) for pristine PS and PSC (50 mg center dot L- 1) and 26.7 % (35.9 %) and 43.1 % (57.8 %) for aged PS and PSC (50 mg center dot L- 1), respectively. NPs induced excessive reactive oxygen species (ROS) production in the leaves and roots, antioxidant defense mechanisms, and oxidative damage, which was more pronounced with aged NPs. ROS accumulation gradually increased with aging time and concentration of NPs, which inhibited photosynthesis and decreased biomass. At the same aging duration, exposure to either pristine or aged NPs significantly reduced soil pH. Compared to the control, neither pristine nor aged NPs altered the composition of dissolved organic matter, whereas aged PSC induced a significant increase in the intensity of soluble microbial byproducts; this was attributed to differences in soil acidity and alkalinity. Low concentrations of pristine and aged NPs increased the Chao 1 index in soils, exhibiting hormesis, and altered relative microbial abundances. Pristine and aged PS/ PSCs promoted microbial oxidative phosphorylation, carbon fixation pathways in prokaryotes, and the tricarboxylic acid cycle. The results provide critical insights into the impacts of NPs on plant and soil microbial growth.