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Ice records provide a qualitative rather than a quantitative indication of the trend of climate change. Using the bulk aerodynamic method and degree day model, this study quantified ice mass loss attributable to sublimation/evaporation (S/E) and meltwater on the basis of integrated observations (1960-2006) of glacier-related and atmospheric variables in the northeastern Tibetan Plateau. During 1961-2005, the average annual mass loss in the ice core was 95.33 +/- 20.56 mm w.e. (minimum: 78.97 mm w.e. in 1967, maximum: 146.67 mm w.e. in 2001), while the average ratio of the revised annual ice accumulation was 21.2 +/- 7.7% (minimum: 11.0% in 1992, maximum 44.8% in 2000). A quantitative formula expressing the relationship between S/E and air temperature at the monthly scale was established, which could be extended to estimation of S/E changes of other glaciers in other regions. The elevation effect on alpine precipitation determined using revised ice accumulation and instrumental data was found remarkable. This work established a method for quantitative assessment of the temporal variation in ice core mass loss, and advanced the reconstruction of long-term precipitation at high elevations. Importantly, the formula established for reconstruction of S/E from temperature time series data could be used in other regions.

期刊论文 2025-07-01 DOI: http://dx.doi.org/10.1017/jog.2023.51 ISSN: 0022-1430

Expanded Polystyrene (EPS) granular lightweight soil (ELS) is an eco-friendly material made of EPS particles, cement, soil, and water. This study investigates the modification of ELS using a silane coupling agent (SCA) solution to improve its performance. Various tests were performed, including flowability, dry shrinkage, unconfined compressive strength (UCS), triaxial, hollow torsional shear, and scanning electron microscopy (SEM) analysis, to evaluate the physical and mechanical properties at different SCA concentrations. The results show that the optimal SCA concentration was 6%, improving flowability by 13% and increasing dry shrinkage weight by 4%. The UCS increased with SCA concentration, reaching 266 and 361 kPa after 7 and 28 days, respectively, at 6% SCA. Triaxial and shear tests indicated improved shear strength, with the maximum shear strength reaching 500 kPa, internal friction angle rising by 4%, and cohesion reaching 114 kPa at 6% SCA. Hollow torsion shear tests showed that 6% SCA enhanced stiffness and resistance to deformation, while reducing the non-coaxial effect. SEM analysis revealed that SCA strengthened the bond between EPS particles and the cement matrix, improving the interfacial bond. This study highlights the potential of modified ELS for sustainable construction.

期刊论文 2025-06-12 DOI: 10.1680/jgein.24.00133 ISSN: 1072-6349

Shredded rubber from waste tyres has progressively been adopted in civil engineering due to its mechanical properties, transforming it from a troublesome waste into a valuable and low-cost resource within an eco-sustainable and circular economy. Granular soils mixed with shredded rubber can be used for lightweight backfills, liquefaction mitigation, and geotechnical dynamic isolation. Most studies have focused on sand-rubber mixtures. In contrast, few studies have been conducted on gravel-rubber mixtures (GRMs), primarily involving poorly-graded gravel. Poorly-graded gravel necessitates selecting grains of specific sizes; therefore, from a practical standpoint, it is of significant interest to examine the behaviour of well-graded gravel and shredded rubber mixtures (wgGRMs). This paper deals with wgGRMs. The results of drained triaxial compression tests on wgGRMs are analysed and compared with those on GRMs. Stress-strain paths toward the critical state and energy absorption properties are evaluated. The tested wgGRMs exhibit good shear strength and remarkable energy absorption properties; thus, they can be effectively utilised in several geotechnical applications.

期刊论文 2025-01-27 DOI: 10.1680/jgein.24.00177 ISSN: 1072-6349

The excessive use of cobalt in various chemical industries and arbitrary discharge of industrial wastewater have led to increased cobalt pollution in soil and water resources, increasing the risk of human exposure to high concentrations of cobalt and necessitating an urgent need for on-site monitoring platform for cobalt pollution. In this study, the terminal deoxynucleotidyl transferase (TdT)-CRISPR platform has been developed. In this platform, cobalt as a cofactor of TdT, can significantly improve the tailing efficiency of TdT-mediated extension. Therefore, when cobalt is present, the detection probe can be extended with poly(T) tails through the TdTmediated extension, which can be subsequently served as the DNA activator for Cas12a, leading to the cleavage of fluorescence reporter molecules and triggering turn-on fluorescence signals. Consequently, this dual amplification sensing strategy of TdT-CRISPR platform demonstrated exceptional sensitivity (0.83 nM) and high specificity for cobalt over other ions. Furthermore, the method was successfully employed for the detection of cobalt in tap water and river samples. CRISPR-lateral flow assays (CRISPR-LFAs) were evaluated in this study for the simple and point-of-care detection of cobalt pollution. The assays are capable of detecting cobalt concentrations as low as 50 nM, which is significantly lower than the environmental standards of 16.9 mu M, through strip analysis with the naked eye. These results commonly suggest that the TdT-CRISPR platform holds significant promise for monitoring cobalt pollution, providing a robust and sensitive solution for on-site detection and contributing to the mitigation of cobalt contamination risks in environmental matrices.

期刊论文 2025-01-01 DOI: 10.1016/j.talanta.2024.126999 ISSN: 0039-9140

The present work attempts to investigate the applicability of using recycled aggregate for the development of pervious concrete and for mitigating liquefaction and reliquefaction effects. The dynamic behaviour of developed recycled aggregate-based pervious concrete pile is compared with natural aggregate-based pervious concrete pile. The study attempts to explore the inherent material properties of pervious concrete keeping permeability equivalent to conventional stone columns but with improved mechanical characteristics with enhanced pore water pressure ratio reduction and soil displacement reduction efficiency under repeated incremental acceleration loading conditions. For testing, 1g shaking table tests were performed with 01 g, 02 g, 03 g and 04 g acceleration loading with 5 Hz frequency. The outcomes obtained from this experimental study infer that recycled aggregate-based pervious concrete pile exhibits a superior performance compared with natural aggregate-based pervious concrete pile. Overall, the use of recycled aggregate found sustainable approach for developing pervious concrete pile and found effective ground improvement application against liquefaction and reliquefaction hazards.

期刊论文 2024-12-19 DOI: 10.1680/jgele.24.00118 ISSN: 2049-825X

Mercury (Hg) is a notorious toxic heavy metal, causing neurotoxicity and liver damage, posing grave threats to human health and environmental safety. There is an urgent imperative for developing novel Hg2+ detection methods. In this work, we developed a CRISPR-based method for Hg2+ detection named CRISPR-Hg. A CRISPR/ Cas12a system was employed and could be activated by the PCR product, generating fluorescence signals based on the trans-cleavage activity. CRISPR-Hg exhibited remarkable selectivity and specificity, achieving a detection limit of 10 pM and minimal interference with background signals. This approach has been successfully applied to detect Hg2+ in real samples, including water, soil, and mushroom. Ulteriorly, a portable device was devised to streamline the readout of fluorescence signals by a smartphone within 30 min. We offer an affordable, highly selective and visually interpretable method for Hg2+ detection, with the potential for broad application in Hg2+ monitoring for food safety and public health.

期刊论文 2024-09-01 DOI: 10.1016/j.talanta.2024.126379 ISSN: 0039-9140

The SLS additive manufacturing industry enables the development of products for diverse applications with distinct properties due to its excellent surface finish and ability to create varied part geometries, but it consumes high-performance materials with high acquisition costs. An extensive quarrying of stone leads to the accumulation of mineral residues, posing environmental hazards by contaminating soil and water when disposed of in landfills. The primary objective of the study was to incorporate mineral waste into the SLS technique and investigate the influence of its addition, along with a silane-based chemical treatment, on the mechanical performance of polymer-mineral composites (PA12-slate). Additionally, the feasibility of producing a highly loaded printed prototype, employing 50 wt% of mineral waste, was examined. Samples of PA12, PA12 blended with 50 wt% slate waste, and slate waste treated with silane underwent fabrication via selective laser sintering (SLS) and subsequent mechanical characterization, including tensile, flexural, and compressive tests. Additionally, the samples underwent accelerated aging using a QUV weathering tester, followed by mechanical characterization. The geometric accuracy, stability, and processing feasibility of these formulations were evaluated through SLS-printed composite prototypes utilizing PA12_50Sla_Si. It was found that the addition of 50% of slate to the PA12 presented mechanical properties decreasing compared to the printed PA12 only. However, an increase was verified when using silane-induced mineral bonding. The incorporation of mineral agents and silane enhanced the resistance of PA12 to aging. However, after aging, both tensile and flexural strength decreased across all printed samples. Nonetheless, this study showcased the feasibility of producing complex PA12-slate waste specimens containing up to 50 wt% of mineral waste using the SLS printing technique. Therefore, SLS presents itself as a viable means of adding value to this mineral waste.

期刊论文 2024-09-01 DOI: 10.1007/s00170-024-13989-8 ISSN: 0268-3768

Stubble burning is a conventional technique of residue management that has affected the physio-chemical properties of the soils. In soil sciences, dielectric properties of soils using radio and microwave-based remote sensing have huge applications. Thus, presented paper has studied the burning effects of stubble on soil's physical, chemical and dielectric properties ($\varepsilon {{\prime}} $epsilon ' and $\varepsilon {{\prime \prime}}$epsilon ''). Moreover, the experimentally observed soil's dielectric data has been explored with various classical Machine Learning (ML) and Neural Network (NN) based regression models. The soil samples were taken from the fields of Punjab, India, in the October-November months following a multistage soil sampling method. Then, Dak-12 open-ended coaxial probe (DOCP) has been used in alliance with a two-port Vector Network Analyzer (VNA) E5071C, Agilent Technologies, to investigate the dielectric properties of soil samples. The obtained results indicate that physio-chemical and dielectric properties have been strongly affected by burning as well as because of the presence of high concentrations of ash residues.$ \varepsilon {{\prime}} $epsilon ' and $\varepsilon {{\prime \prime}}$epsilon '' variations with depth indicate that ash residues can seep up to depths of 10 cm in a single burning process. Moreover, the continuous burning of stubble can have permanent effects on soil's properties. Among considered regression models, the Deep NN-based regression model has given the most accurate predictions of the regressor variables $\varepsilon {{\prime}} $epsilon ' and $\varepsilon {{\prime \prime}}$epsilon '', with a root-mean-square-error (RMSE) of 0.06 and 0.07, respectively. Stubble burning has visible effects on physical, chemical as well as dielectric properties of soil. The burning of stubble damages natural ecosystem and essential nutrients which decrease fertility of soil. Also, the resultant residue ash becomes permanent part of soil profile and alters basic properties of soil. Moreover, exploration of ML-based regression models suggests the tremendous applications of data-centric models in soil and material sciences.

期刊论文 2024-08-17 DOI: 10.1080/15320383.2023.2249993 ISSN: 1532-0383

Under lunar polar cold traps, volatile molecules within porous regolith may experience temperature and depth dependent slow mobility. Many degraded lunar craters exhibit thick regolith fill based on models of topographic diffusion and observations of fresh and degraded craters. Regolith has a low thermal conductivity relative to megaregolith and may act as a blanket for internal lunar heat flow, leading to increased temperatures at depth. We develop 2D thermal models of fresh and regolith-filled lunar craters over depths of meters to hundreds of meters below the surface. We find that the base of the stability and slow mobility zones migrate upward with regolith fill, which leads to temperatures that may increase the sublimation rate of volatiles at depth. For a notional cold trap crater 1.6 km in diameter and 3.6 billion years old, topographic diffusion fills it with approximately 90 m of regolith, and the regolith fill's blanketing effect causes the 110 K isotherm to shift about 180 m upward. This places it approximately 25 m below the current cold trap surface and well above the initial crater floor. The slow water ice mobility zone below the 110 K isotherms also shifts upward with regolith fill, potentially increasing volatile concentrations at shallower depths. These secondary volatile concentrations may be targets for sampling and testing hypotheses of volatile system processes. In addition, remobilized volatile concentrations may be a resource for future In -Situ Resource Utilization (ISRU) applications. The thick regolith fill in degraded craters and volatile remobilization potential in lunar subsurface cold traps have implications for future exploration instruments, sampling, and ISRU architectures.

期刊论文 2024-03-15 DOI: 10.1016/j.icarus.2024.115953 ISSN: 0019-1035

全球变化导致气温上升加速冰川退缩,冰川前缘进化出大量抗辐射-抗氧化微生物资源。细菌作为影响冰川前缘演替过程的重要类群之一,对其冰舌区新融化的冰碛物生境中抗辐射-抗氧化细菌的研究却较为少见。基于16S rRNA基因序列系统发育学的研究,不仅对老虎沟12号冰川前缘冰舌区冰碛物生境可培养细菌多样性进行研究,同时对菌株的抗辐射和抗氧化能力进行筛选和评估。研究表明,研究区域分离出的259株细菌分别归属于放线菌门(Actinobacteria)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和异常球菌-栖热菌门(Deinococcus-Thermus),其中放线菌门的菌株数量最多,其次是变形菌门>拟杆菌门>厚壁菌门>异常球菌-栖热菌门;在物种多样性方面,放线菌门和变形菌门是物种丰富度最高的门。TN、TOC、WC和pH是影响可培养细菌群落结构的主要因素。UVC辐照强度的D10(致死率为10%)剂量高于100 J·m-2的菌株占可培养细菌总数的94.9%,过氧化氢耐受浓度的...

期刊论文 2024-02-29
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