Friction characteristics are critical mechanical properties of clay, playing a pivotal role in the structural stability of cohesive soils. In this study, molecular dynamics simulations were employed to investigate the shear behavior of undrained montmorillonite (MMT) nanopores with varying surface charges and interlayer cations (Na+, K+, Ca2+), subjected to different normal loads and sliding velocities. Consistent with previous findings, our results confirm that shear stress increases with normal load. However, the normal load-shear stress curves reveal two distinct linear regions, indicating segmented friction behavior. Remarkably, the friction coefficient declines sharply beyond a critical pressure point, ranging from 5 to 7.5 GPa, while cohesion follows an inverse trend. The elevated friction coefficient at lower pressures is attributed to the enhanced formation of hydrogen bonds and concomitant changes in density distribution. Furthermore, shear strength was observed to increase with sliding velocities, normal loads, and surface charges, with Na-MMT exhibiting superior shear strength compared to KMMT and Ca-MMT. Interestingly, the friction coefficient shows a slight decrease with increasing surface charge, while ion type exerts a minimal effect. In contrast, cohesion is predominantly influenced by surface charge and remains largely unaffected by ion type, except under extreme pressures and velocities.

The laying of the underground pipeline in the same ditch has caused great challenges to the attractive transportation mode of hydrogen mixed with natural gas pipeline in service. The tendency to damage of hydrogen to steel increases the possibility of flammable and explosive gas entering underground engineering significantly. A leakage monitoring method for buried hydrogen-doped natural gas pipeline based on vibration signals with machine learning is proposed. Firstly, the distributed vibration sensor captures the multisource vibration signals propagating in the soil. An optimal combination of wavelet basis functions, decomposition level, and threshold parameters is selected carefully for signal denoising and accurate extraction of leakage-generated signals. Then the characteristics extracted in different frequency bands are investigated with other influencing factors, including the hydrogen-doping ratio, which affects the propagation speed of the pressure wave. The unique characteristics of vibration signal generated by pipeline leakage are extracted. On this basis, combined with the high efficiency of machine learning recognition model, a leakage monitoring model for buried hydrogen-doped natural gas pipeline is established, which achieves a 2.01 % false alarm rate at a maximum positioning distance of 70 cm. It has been successfully applied to the leak detection and location of buried hydrogen-doped natural gas pipelines, which can significantly improve the safety and reliability of underground pipeline system engineering.

BackgroundForensic entomotoxicology is a crucial field that studies the effects of drugs and poisons on carrion-feeding insects, particularly in crime investigations. Hydrogen cyanamide, a plant growth regulator, is hazardous and used in agriculture but is limited in some countries due to its high cost and severe toxicity. The terrestrial isopod Porcellio laevis plays a vital role in soil ecosystems and biosystem management. Accordingly, authors aimed to examine the impact of hydrogen cyanamide toxicity on arthropods, specifically Porcellio laevis, Musca domestica (House flies), and Sarcophaga sp. (Flesh flies) visiting decomposing covered/uncovered rat carrions, which could be relevant in forensic investigations. A total of 20 rats were divided into two control (I and II, covered/uncovered) and two treated groups (III and IV, covered/uncovered, euthanized using hydrogen cyanamide). Arthropods were gathered bi-daily during the initial week and then once daily for a duration of 1 month and were assessed for growth rate. Morphological and histological alterations were analyzed using light and electron microscopes.ResultsThe results revealed that hydrogen cyanamide caused a delay in postmortem interval (PMI) by 22-33 h in certain insect species, particularly in uncovered carrion. Severe damage was observed in the carrions of Groups III and IV, specifically Porcellio laevis.ConclusionA scanning electron microscope (SEM) would be beneficial for scrutinizing insects as postmortem toxicological specimens.

Ironmaking- steelmaking is a material and energy intensive process with a resource efficiency of only - 33 %. Resource efficiency enhancement requires recovering the wasted/unutilized material by-products and the energy associated with them in various forms. This review attempts to identify the material leakages and energy losses at each step of steelmaking (from iron ore mining) and explores approaches to plug the energy and material leakage; material efficiency brings in energy savings indirectly. Besides the material loss, accumulation of the byproducts (slime/tailings, steel slag, etc.), carbon emission, etc., cause environmental and ecological damage. The review discusses the prospects of slimes/tailings beneficiation through physical and physicochemical methods (often after some pretreatments). The manuscript also discusses the need to recover heat from molten slags (BF slag and BOF slag) to reduce the energy intensity. Further, it discusses the endeavors to overcome the latent hydraulic activity of granulated BF slag and ways to enhance the acceptability of BOF slag in different applications. A brief sum-up of global efforts towards net zero emission (in line with the Paris Declaration) through carbon recycling, low emission intensity processes, alternate fuels, etc., is included. Lastly, the authors list the challenges of the Indian iron & steel industry and the efforts from the government and steel industries towards achieving the projected crude steel production (300 million tons) without crossing the emission intensity thresholds (Paris Declaration). The endeavors strengthen the sustainability of the steel industry.

Phosphorus and potassium are essential macronutrients, and potassium dihydrogen phosphate, a compound containing both, plays a vital role in plant growth and reproduction. However, its rapid leaching poses significant environmental concerns, lessening its practical utility. To overcome this issue, a biodegradable hydrogel based on amla was synthesized through graft polymerization and evaluated as a water-retaining material for agricultural applications, specifically for the controlled release of fertilizers. The synthesized hydrogel was characterized using FTIR, SEM, XRD, and TGA. Its swelling properties, water retention capacity, porosity, and density were also examined. The biodegradable nature of the synthesized hydrogel was confirmed via soil burial and composting techniques, with FTIR used to validate the degradation. The hydrogel degraded almost entirely within 64 days in compost soil and 72 days in burial soil. Finally, potassium dihydrogen phosphate release studies were conducted, and the data were analyzed using Fick's law of diffusion and various kinetic models (zero order, first order, Higuchi, and Korsemers Peppas). The release pattern was measured via UV spectrophotometry over 45,000 min, demonstrating controlled nutrient delivery. These findings suggested that the synthesized hydrogel matrix has strong potential as an effective water retention system and for regulated nutrient release.

Soil salinization is a severe environmental issue limiting the growth and yield of crops worldwide. Subsurface drip irrigation with micro-nano bubble hydrogen water (SDH) is an innovative way to realize the role of hydrogen gas (H2) in improving plant resistance to salt stress in practical agricultural productions. Nonetheless, limited information is available on how SDH affects the plant salt tolerance performance. Especially, the underlying physiological respond, hormone-regulated and soil microbial-mediated mechanisms have not been reported so far. In this study, the effects of SDH on lettuce (Lactuca sativa L.) growth, photosynthesis, root development, antioxidant system, phytohormone, and soil microbial community were investigated under normal and salt stress conditions. The results showed that, with salt stress, SDH significantly enhanced the lettuce fresh weight, photosynthesis activity, and root growth. The leaf antioxidant enzyme activities increased and reactive oxygen species (ROS) content decreased to reduce the oxidative damage. The decreased malondialdehyde (MDA) content indicated a low membrane lipid peroxidation responsible for cellular damage. SDH also helped to maintain osmotic homeostasis, which was reflected by the increased soluble protein (SP) content. Reduced Na+/ K+ ratio and ROS did not trigger excessive production of stress response hormones abscisic acid (ABA) and jasmonic acid (JA), which alleviated the mediated growth inhibition effects. SDH enriched the abundance of the plant growth-promoting rhizobacteria (PGPR) in the soil, such as Arthrobacter and Pseudomonas. That might be the reason for explaining the increase in hormone indoleacetic acid (IAA) in lettuce and 1-aminocyclopropane-1carboxylate (ACC) deaminase activity in the soil, which was beneficial for inhibiting ethylene production and promoting plant growth. Under the normal condition, variations of physiological and growth indicators as affected by SDH were similar to those under the salt stress condition, except for root development. High concentration of dissolved hydrogen gas in water might expel the oxygen. The induced soil anoxic environment limited oxygen diffusion, in turn inhibited root respiration and growth. The effect of hydrogen concentration on the plant tolerance against salt stress under different salt content could be further studied.

Iron (Fe) deficiency is a critical constraint on global food security, particularly affecting high-value horticultural crops such as strawberries (Fragaria x ananassa). This study examines the roles of melatonin and hydrogen sulfide (H2S) signaling in mitigating Fe deficiency stress by improving Fe bioavailability and enhancing plant resilience. Strawberry plants were cultivated under Fe-sufficient and Fe-deficient conditions and treated with 100 mu M melatonin and 3 mM dl-propargylglycine (PAG), an inhibitor of L-cysteine desulfhydrase (L-DES), which regulates H2S production. Fe deficiency significantly reduced chlorophyll content and photosynthetic efficiency while elevating oxidative stress markers such as hydrogen peroxide (H2O2), malondialdehyde (MDA), and electrolyte leakage (EL). Melatonin application alleviated Fe deficiency effects by enhancing Fe utilization, stimulating L-DES activity, and promoting H2S production. Melatonin also improved antioxidant defenses by boosting the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), as well as maintaining ascorbate-glutathione (AsA-GSH) redox dynamics. The addition of 3 mM PAG inhibited L-DES activity, resulting in reduced H2S levels and diminished melatonin-induced benefits, underscoring the essential role of L-DES-mediated H2S synthesis. Despite the presence of PAG, the co-application of 0.2 mM sodium hydrosulfide (NaHS) and melatonin restored Fe bioavailability, growth, and antioxidant capacity, suggesting a synergistic interaction between melatonin and H2S. This study highlights the potential of melatonin and H2S signaling to improve Fe homeostasis and mitigate oxidative stress in Fe-deficient plants. The findings offer strategies to enhance crop resilience and productivity in nutrient-deficient soils, thereby promoting sustainable agriculture and global food security.

High-Density Polyethylene (HDPE) PE is one of the primary contributors of long-lasting and prolonged pollution in the environment. In this study, more than three hundred marine isolates collected off the Gujarat Sea coast were tested for HDPE plastic utilizing ability. Among fifty-one positive noted isolates, RS124 as a potential strain was identified as Micrococcus flavus (accession is PP858228) based on 16 S rRNA gene sequencing and total cellular fatty acid profiling. Initial bacterial adherence on the film surface was shown in a scanning electron microscopy (SEM) image as a key step to biodegradation. Moreover, atomic force microscopy (AFM) shows that the film surface became more fragile, damaged, and rougher than untreated films. Shifts and alterations in peak transmittance with emergence of two new shouldered peak in degraded HDPE observed by fourier transform infrared spectroscopy (FTIR) was associated to chemical and mechanical alteration. Thermogravimetric analysis (TGA) analysis designated larger difference in percent weight loss provisions thermal instability. In the enzymatic study, the highest activity of peroxidase and dehydrogenase was recorded on the 3rd and 4th weeks of treatment with strain, respectively, during co-incubation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis disclosed the presence of a distinct 19 kDa size protein, uncovering its role in the colonization of bacteria on the hydrophilic HDPE surfaces. About 1.8% weight reduction in HDPE was recorded as a result after 30 days of bio-treatment with M. flavus. Hence, the entire observed results reveal that the M. flavus RS124 could be effectively applied for the degradation of HDPE. This is the first report on M. flavus that it exhibits plastic degrading characteristic ever, which may allow for green scavenging of plastic waste.

Urban air pollution has been a global challenge world-wide. While urban vegetation or forest modelling can be useful in reducing the toxicities of the atmospheric gases by their absorption, the surge in gaseous pollutants negatively affects plant growth, thereby altering photosynthetic efficiency and harvest index. The present review analyses our current understanding of the toxic and beneficial effects of atmospheric nitrogen oxides (NOx), hydrogen sulphide (H2S) and carbon monoxide (CO) on plant growth and metabolism. The atmospheric levels of these gases vary considerably due to urbanization, automobile emission, volcanic eruptions, agricultural practices and other anthropological activities. These gaseous pollutants prevalent in the atmosphere are known for their dual action (toxic or beneficiary) on plant growth, development and metabolism. NO seems to exert a specialized impact by upregulating nitrogen metabolism and reducing tropospheric ozone. High H2S emission in specific areas of geothermal plants, fumarolic soils and wetlands can be a limitation to air quality control. Certain shortcomings associated with the designing of field experiments, sensitivity of detection methods and simulation development are yet to be overcome to analyze the precise levels of NO, H2S and CO in the rhizosphere of diverse agro-climatic regions. Several laboratory-based investigations have been undertaken to assess the roles of atmospheric gases, namely NOx, CO, H2S, and particulate matter (PM). However, in order to enable natural and sustainable mitigation, it is essential to increase the number of field experiments in order to identify the pollutant-tolerant plants and study their interactive impact on plant growth and agriculture.

Hazardous alkylphenol wastes (HAPW) are a class of organic semisolid waste characterized by large production, complex composition and difficulties associated with recycling. Their generation and disposal lead to significantly environmental issues, including water and soil pollution, and present a substantial industrial challenge. To address these issues, a sustainable, low-carbon strategy for the high-value utilization of HAPW has been proposed. We take HAPW as a compatibilizer in the production of epoxy asphalt for road construction materials. Experimental results show that the HAPW-based epoxy asphalt containing 19.5 wt% HAPW exhibited optimal mechanical properties (tensile strength: 4.16 MPa; elongation at break: 164.92 %), exceeding industrial standards and outperforming epoxy asphalt produced using commercial cardanol through conventional processes. With a detailed molecular dynamics simulation, it is found that the HAPW plays two key roles in enhancing the interactions between epoxy resins and asphalt: (i) HAPW generates numerous hydrogen bonds with both asphalt and epoxy resin phases, strengthening noncovalent interactions and improving interfacial miscibility between the two phases. (ii) HAPW could react with the epoxy resin through the phenolic hydroxyl group, which further improves the interactions between epoxy resin and asphalt. This approach facilitates the treatment of hazardous organic waste in an environmentally sustainable and low-carbon way, enabling the recovery and repurposing of organic waste into high-valued products. Consequently, it promotes the resource utilization of industrial wastes while simultaneously contributing to a reduction in carbon emissions.