Journal of contaminant hydrology最新文献_第8页

Directional injection-driven contaminants transport in groundwater system with asymptotically varying dispersion coefficients 离散系数渐近变化的地下水系统中定向注入驱动的污染物运移

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104813

S. Nagouda Smita, R. Iyer Aiswarya

This work examines the effect of asymptotic dispersion for different contaminants, like heavy metals, biological, and radiological types, in heterogeneous groundwater systems. The migration of contaminants within groundwater systems is controlled by advection, dispersion, and sorption phenomena, and these mechanisms are mathematically modeled using the Advection-Dispersion Equation (ADE). Using the Thomas algorithm, a numerical simulation with the Peaceman - Rachford Alternating Direction Implicit (PR-ADI) scheme is applied to solve the ADE under the directional injection boundary (axial input sources). The study on asymptotic dispersion coefficients revealed a broader plume evolution. Non-linear sorption models depended on the saturation limit, and various parameters revealed physically relevant results. The iso-concentration figures depict flow patterns for diverse directional hydrological inflows, supporting stability interpretations. This study introduces a computational approach for modeling contaminant transport in groundwater systems, emphasizing asymptotic field conditions that introduce heterogeneity, coupled with nonlinear sorption effects on the plume morphology. The results highlight how plume morphology responds to variable dispersion and velocity, offering guidance for field-scale aquifer analysis and water quality management. The study is also aligned with Sustainable Development Goal 6 - Clean water and sanitation.

本研究考察了非均质地下水系统中不同污染物（如重金属、生物和放射类型）的渐近分散效应。地下水系统中污染物的迁移受平流、弥散和吸附现象的控制，这些机制使用平流-弥散方程（ADE）进行数学建模。采用Thomas算法，采用Peaceman - Rachford交替方向隐式（r - adi）格式进行数值模拟，求解定向注入边界（轴向输入源）下的ADE。渐近色散系数的研究揭示了更广泛的羽流演化。非线性吸附模型依赖于饱和极限，各种参数揭示了物理相关的结果。等浓度图描绘了不同方向水文流入的流动模式，支持稳定性解释。本研究引入了一种模拟地下水系统中污染物运移的计算方法，强调了引入非均质性的渐近场条件，以及对羽流形态的非线性吸收效应。研究结果突出了羽流形态对不同分散和速度的响应，为现场尺度的含水层分析和水质管理提供了指导。这项研究也符合可持续发展目标6——清洁水和卫生设施。

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引用次数: 0

Spatiotemporal assessment of toxic metals in total suspanded matter and surface sediments of Borçka Reservoir (Türkiye): Tracing pollution and ecological risk implications borka水库（trkiye）总悬浮物和表层沉积物中有毒金属的时空评价：追踪污染和生态风险影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104814

Koray Özşeker , Yahya Terzi , Coşkun Erüz

This study investigates the spatiotemporal variations of toxic metals (Cu, Pb, Zn, Ni, As) in both suspended particulate matter (SPM) and surface sediments of the Borçka Reservoir (Türkiye) to trace pollution dynamics and evaluate ecological risks. The Borçka Reservoir, located in the southeastern Black Sea basin, is an ecologically and hydrologically important freshwater system affected by intensive human activities. Seasonal sampling was performed at four representative stations throughout 2023. The highest metal enrichment was observed in the upstream region, particularly during autumn, indicating the influence of inflowing waters from the Murgul Stream, a major tributary draining mining areas and discharging into the reservoir. Maximum sediment concentrations reached 446.5 μg/g for Cu, 170.7 μg/g for Pb, and 356.33 μ/kg for Zn, exceeding the Probable Effect Level (PEL; Cu: 197, Pb: 91.3, Zn: 315 μg/g) and Effect Range Median (ERM; Cu: 270, Pb: 218, Zn: 410 μg/g) thresholds of sediment quality guidelines. Enrichment and contamination factors classified Cu as “extremely severe” (class 6), while ecological risk (Er) and toxic risk (TRI) values revealed moderate to considerable risks for Cu and Pb. In SPM, metals also showed autumnal peaks. Physicochemical parameters (pH: 8.17–8.53; TOC: 0.52–0.93%) strongly influenced metal retention. The integrated assessment highlights spatiotemporal heterogeneity of metal pollution and emphasizes the need for continuous monitoring and source-based management strategies for sustainable reservoir ecosystems.

研究了borka水库（trkiye）悬浮颗粒物（SPM）和表层沉积物中有毒金属（Cu、Pb、Zn、Ni、As）的时空变化规律，以追踪污染动态并评价生态风险。borka水库位于黑海盆地东南部，是一个受人类活动强烈影响的重要的生态和水文淡水系统。整个2023年在四个代表性站点进行了季节性采样。在上游地区观察到最高的金属富集，特别是在秋季，这表明来自穆尔古尔河的流入水的影响，穆尔古尔河是一条主要支流，为矿区排水并排入水库。最大沉积物浓度Cu为446.5 μg/g， Pb为170.7 μg/g， Zn为356.33 μ/kg，超过了沉积物质量指南的可能影响水平（PEL; Cu: 197, Pb: 91.3, Zn: 315 μg/g）和影响范围中位数（ERM; Cu: 270, Pb: 218, Zn: 410 μg/g）阈值。富集和污染因子将Cu列为“极严重”（6级），而生态风险（Er）和毒性风险（TRI）值显示Cu和Pb的中度至相当风险。在SPM中，金属也出现了秋季峰值。理化参数（pH: 8.17-8.53; TOC: 0.52-0.93%）强烈影响金属的保留。综合评价强调了金属污染的时空异质性，强调了对可持续水库生态系统进行持续监测和基于源头的管理战略的必要性。

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引用次数: 0

Density-dependent flow, solute transport and mixing in the Fraser River delta aquifer 弗雷泽河三角洲含水层的密度依赖性流动、溶质运输和混合

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104816

Yaguang Zhu , Kun Jia , Roger D. Beckie

Groundwater flow in coastal aquifers is influenced by density differences between freshwater and saline water, forming a complex density-dependent flow system. The relatively narrow zone where freshwater and saline water mix is the location of strong geochemical gradients, which can drive reactions. Understanding the dynamics of this mixing zone is crucial to understand the biogeochemical reactions that occur during saline intrusion. In this study, we characterized flow and dispersive mixing in a confined sand aquifer subjected to saline intrusion, using both field observations and numerical modeling. Observations from an extensive monitoring network revealed a saline wedge extending approximately 500 m inland. We simulated density-dependent flow with MIN3P and used PEST++ to estimate dispersivity and diffusion from field observations. In effect, we use salinity data to measure the dispersivity through inverse modeling. The longitudinal and transverse dispersivity were calibrated at 0.1 m and 0.001 m, respectively, while the molecular diffusion coefficient was 1.2 × 10⁻⁹ m²/s. Sensitivity analyses show that transverse dispersivity affects mixing-zone characteristics more than longitudinal dispersivity. Our results highlight the importance of accurately estimating dispersivity values to model the width of the mixing zone, which strongly controls geochemical reactions at the site. These findings provide insights into the processes driving freshwater–saline water mixing in coastal aquifers and offer guidance for future modeling studies on geochemical dynamics during saline intrusion.

沿海含水层的地下水流动受到淡水和咸水密度差的影响，形成了一个复杂的密度依赖流动系统。相对狭窄的淡水和咸水混合带是地球化学梯度强的位置，可以驱动反应。了解这一混合带的动力学对于理解盐水侵入过程中发生的生物地球化学反应至关重要。在这项研究中，我们采用现场观测和数值模拟的方法，对受盐水入侵的承压砂含水层的流动和分散混合进行了表征。来自广泛监测网络的观测显示，一个向内陆延伸约500米的盐楔。我们用MIN3P模拟了密度相关的流动，并使用PEST++从现场观测中估计了分散性和扩散。实际上，我们使用盐度数据通过逆建模来测量分散性。纵向和横向色散分别标定为0.1 m和0.001 m，分子扩散系数为1.2 × 10−9 m2/s。灵敏度分析表明，横向色散比纵向色散对混合区特性的影响更大。我们的研究结果强调了准确估计色散值对模拟混合带宽度的重要性，混合带宽度强烈地控制着现场的地球化学反应。这些发现为了解沿海含水层淡水-咸水混合的过程提供了见解，并为未来盐水入侵过程中地球化学动力学的建模研究提供了指导。

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引用次数: 0

Aggregation kinetics and stability of Ce(IV)-borate colloid: Effect of pH, electrolytes, gibbsite colloid, and humic acid colloid Ce(IV)-硼酸胶体的聚集动力学和稳定性：pH、电解质、三水铝石胶体和腐殖酸胶体的影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104811

Kang Chen , Rui Zhang , Chunsheng Shi , Shanrong Yuan , Zishuo Li , Daming Zhang , Qiang Jin , Zhijun Guo , Zongyuan Chen

Tetravalent actinides (An(IV)), could be released from high-level radioactive waste (HLW) glass in the form of An(IV)-borate intrinsic colloid. In this study, Ce(IV) was selected as the analogue of An(IV), and the stability of Ce(IV)-borate colloid was studied as a function of pH, electrolytes, gibbsite colloid, and humic acid (HA) colloid by aggregation kinetics experiments. The isoelectric point (pH_IEP) of Ce(IV)-borate colloid was determined to be 7.8, and aggregation of the colloid was increased progressively with the pH approaching this value. The critical coagulation concentrations (CCC) were followed the order that NaCl > KCl > MgCl₂ > NaNO₃ > CaCl₂ > Na₂SO₄. The positively charged gibbsite colloid inhibited the aggregation of Ce(IV)-borate colloid due to enhanced electrostatic repulsion. In contrast, the effect of negatively charged HA on the stability of Ce(IV)-borate colloid was dependent on HA concentration. The presence of low concentrations of HA (0.1–1.0 mg/L) reduced the surface charge of Ce(IV)-borate colloids, resulting in lower CCC, whereas the higher HA concentrations (2.5–25 mg/L) enhanced the colloidal stability of Ce(IV)-borate particles. The Hamaker constant of Ce(IV)-borate colloid was calculated to be 1.29 × 10⁻²⁰ J. The interaction energy calculated with Derjaguin–Landau–Verwey–Overbeek (DLVO) theory and its variants can well describe the changes of colloidal stability. These results provide comprehensive understanding of Ce(IV)-borate colloid properties and offer valuable insights for assessing the fate and transport of An(IV) in real subsurface environments.

四价锕系元素（An(IV)）可以从高放废物（HLW）玻璃中以An(IV)-硼酸盐固有胶体的形式释放。本研究选择Ce（IV）作为An（IV）的类似物，通过聚集动力学实验研究Ce(IV)-硼酸盐胶体的稳定性随pH、电解质、三水石胶体和腐殖酸（HA）胶体的变化规律。测定了Ce(IV)-硼酸酯胶体的等电点（pHIEP）为7.8，随着pH值的接近，胶体的聚集性逐渐增强。临界混凝浓度（CCC）顺序为NaCl >； KCl > MgCl2 > NaNO3 > CaCl2 > Na2SO4。带正电的三水铝石胶体由于静电斥力增强而抑制了Ce(IV)-硼酸钙胶体的聚集。相反，带负电荷的HA对Ce(IV)-硼酸酯胶体稳定性的影响依赖于HA浓度。低浓度的HA （0.1 ~ 1.0 mg/L）降低了Ce(IV)-硼酸酯胶体的表面电荷，导致CCC降低，而高浓度的HA （2.5 ~ 25 mg/L）增强了Ce(IV)-硼酸酯颗粒的胶体稳定性。计算得到Ce(IV)-硼酸盐胶体的Hamaker常数为1.29 × 10−20 j，用Derjaguin-Landau-Verwey-Overbeek （DLVO）理论及其变体计算得到的相互作用能可以很好地描述胶体稳定性的变化。这些结果提供了对Ce(IV)-硼酸盐胶体性质的全面理解，并为评估An（IV）在真实地下环境中的命运和运移提供了有价值的见解。

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引用次数: 0

Adsorption of some hazardous aromatic hydrocarbons by various pristine and heat-activated aged microplastics as potential pollutant carriers in aquatic environment 各种原生和热活化老化微塑料作为潜在污染物载体对水生环境中有害芳烃的吸附研究

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104817

Delaram-Sadat Tavoussi-Shirazi , Kamand-Sadat Abdolhosseini , Amir Hossein Hamidian , Habib Bagheri

Microplastics (MPs) are ubiquitous in terrestrial and aquatic ecosystems and persistent micropollutants of concern. Their persistence poses risks to ecosystems, human health, and organisms, while they can facilitate the migration and transformation of persistent organic pollutants by acting as vectors for their transportation into the environment and living organisms. This study examined the adsorption/desorption behavior of three nonpolar polycyclic aromatic hydrocarbons (pyrene, anthracene, and fluorene) on pristine and aged MPs, i.e., polystyrene (PS), polyvinyl chloride (PVC), and polymethyl methacrylate (PMMA) through a series of batch adsorption experiments conducted under different pH values, contact times, and salinities. Results indicate that PS adsorbs higher amounts of PAHs than other MPs due to its rough surface, pores, and aromatic configuration strong π–π interactions. The PAHs adsorption followed a pseudo-second-order model, and fit best with the Freundlich isotherm due to multilayer adsorption. Aging with K₂S₂O₈ for 5 days enhanced adsorption on PMMA through surface roughening, reduced sorption on PVC due to oxidation, while PS exhibited minimal impact. The study examined PAHs desorption from MPs in fasted state simulated gastric fluid (FaSSGF), deionized water, and river water. (FaSSGF) showed the highest desorption rates, with pepsin enhancing desorption through micelle formation and weakening π-π interactions,. These findings highlight how organic pollutants are transported by both pristine and aged microplastics, and demonstrate the risk of desorption of these contaminants in aqueous and gastric environments, which may impact on ecosystems and human health.

微塑料（MPs）在陆地和水生生态系统中普遍存在，是令人关注的持久性微污染物。它们的持续存在对生态系统、人类健康和生物体构成风险，同时它们可以作为持久性有机污染物进入环境和生物体的载体，促进其迁移和转化。本研究通过一系列的间歇吸附实验，考察了三种非极性多环芳烃（芘、蒽和芴）在不同pH值、不同接触时间和不同盐度下对原始和老化MPs（聚苯乙烯（PS）、聚氯乙烯（PVC）和聚甲基丙烯酸甲酯（PMMA））的吸附/解吸行为。结果表明，由于PS表面粗糙、孔隙大、芳香族结构强的π -π相互作用，其吸附多环芳烃的量高于其他MPs。多环芳烃的吸附服从伪二阶模型，多层吸附最符合Freundlich等温线。用K₂S₂O₈时效5天，通过表面粗化增强了对PMMA的吸附，由于氧化减少了对PVC的吸附，而PS的影响最小。该研究检测了禁食状态模拟胃液（FaSSGF）、去离子水和河水中MPs对PAHs的解吸。（FaSSGF）的解吸率最高，胃蛋白酶通过胶束形成和减弱π-π相互作用增强解吸。这些发现强调了有机污染物是如何通过原始和老化的微塑料运输的，并证明了这些污染物在水环境和胃环境中解吸的风险，这可能会影响生态系统和人类健康。

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引用次数: 0

Impact of aging on nanoplastic aggregation and release from low-density polyethylene (LDPE) 老化对低密度聚乙烯（LDPE）纳米塑料聚集和释放的影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-13 DOI: 10.1016/j.jconhyd.2025.104809

Somayeh Saliminasab, Tao Cheng

The pervasive use of plastics has led to significant environmental pollution, with nanoplastics (NPs) emerging as a critical yet less understood component that poses elevated risks due to high mobility, bioavailability, and toxicity. To address the limitations of using artificial pristine NP proxies, we investigated the aggregation of NPs released from low-density polyethylene (LDPE) using ultraviolet (UV) irradiation and heat treatment. We measured physicochemical property changes, conducted aggregation experiments in various electrolyte solutions, applied DLVO theory, and developed a mathematical model to simulate aggregation kinetics. Our findings reveal that aging processes, particularly heat treatment, significantly promote NP generation from LDPE and alter their physicochemical properties such as surface charge. NP aggregation is notably influenced by aging, pH, and cation valence. Heat-aged NPs exhibited enhanced stability due to more negative surface charges, while UV-aged NPs showed complex aggregation behavior in the presence of Ca²⁺, potentially due to bridging effects. The effect of aging and water chemistry on aggregation in most cases can be explained by the DLVO theory. The simple model we developed effectively simulated the observed aggregation kinetics. These results underscore the critical role of aging in determining NP generation and aggregation dynamics. This study highlights both the applicability and limitations of using artificial NPs as environmental proxies and emphasizes the need for further research on the properties and behavior of real-world, aged nanoplastics to improve predictions of their environmental fate and transport.

塑料的广泛使用导致了严重的环境污染，纳米塑料（NPs）成为一种关键但鲜为人知的成分，由于其高流动性、生物利用度和毒性，其风险增加。为了解决使用人工原始NP代理的局限性，我们使用紫外线（UV）照射和热处理研究了低密度聚乙烯（LDPE）释放的NP的聚集。我们测量了其理化性质的变化，并在不同的电解质溶液中进行了聚集实验，应用DLVO理论，建立了模拟聚集动力学的数学模型。我们的研究结果表明，老化过程，特别是热处理，显著促进了LDPE的NP生成，并改变了它们的物理化学性质，如表面电荷。NP聚集明显受老化、pH和阳离子价的影响。热老化NPs由于更多的表面负电荷而表现出更高的稳定性，而紫外线老化NPs在Ca2+存在下表现出复杂的聚集行为，可能是由于桥接效应。在大多数情况下，老化和水化学对团聚的影响可以用DLVO理论来解释。我们建立的简单模型有效地模拟了观察到的聚集动力学。这些结果强调了衰老在决定NP生成和聚集动力学中的关键作用。本研究强调了使用人工NPs作为环境代理的适用性和局限性，并强调需要进一步研究现实世界中老化纳米塑料的特性和行为，以改进对其环境命运和运输的预测。

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引用次数: 0

Intensive anthropogenic activities drive dynamic surface water-groundwater interactions: Implications for contaminant pathways at a catchment scale 密集的人为活动驱动动态地表水-地下水相互作用：对集水区尺度上污染物途径的影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-10 DOI: 10.1016/j.jconhyd.2025.104808

Shunqing Jia , Xihua Wang , Y. Jun Xu , Chaomeng Dai , Nianqing Zhou , Zejun Liu , Boyang Mao , Qinya Lv , Xuming Ji , Chengming Luo , Yan Dai , Yanxin Rong

Interactions between surface water and groundwater (SW-GW) are critical interfaces controlling contaminant fate and transport. However, their dynamic behavior at the catchment scale under intensive anthropogenic stress remains poorly understood. This study integrates hydrogeochemical and isotopic analyses (δ¹⁸O, δ²H) to investigate the spatiotemporal patterns of SW-GW interactions and their implications for contaminant pathways in the Yiluo River Watershed, a major agricultural region in China. Three sampling campaigns were conducted across low-flow (Nov 2022, T1), normal-flow (May 2023, T2), and high-flow (Aug 2023, T3) periods. Results show that while waters are predominantly Ca–HCO₃ type, geochemical and isotopic signatures reveal highly dynamic exchange processes. Isotopic enrichment from upstream to downstream (δ¹⁸O from ∼ − 10 ‰ to ∼ − 6.5 ‰) indicates significant evaporation and mixing. Crucially, SW-GW interactions create fluctuating pathways for contaminants like nitrate (NO₃⁻). During the T1 dry/irrigation season, extensive groundwater abstraction for agriculture reverses local hydraulic gradients, reducing river-to-groundwater recharge and inducing high-nitrate groundwater discharge into the river, with groundwater NO₃⁻ concentrations reaching up to 42.5 mg/L. Correlation analysis reveals that the dominant controls on recharge ratios shift seasonally: from cropland (r = −0.53) and forest (r = 0.49) in the dry season to population density (r = −0.26) and bare land (r = 0.35) in the wet season. These findings reveal a conceptual framework where seasonal human activities (e.g., irrigation vs. urban runoff) actively switch the direction and magnitude of contaminant exchange pathways between surface and subsurface systems. This study highlights the necessity of integrated, dynamic management of SW-GW resources to mitigate contamination risks in anthropogenically-dominated agricultural catchments worldwide.

地表水和地下水相互作用是控制污染物命运和运移的关键界面。然而，在强烈的人为压力下，它们在流域尺度上的动态行为仍然知之甚少。本研究结合水文地球化学和同位素分析（δ18O, δ2H），探讨了中国主要农业区沂罗河流域SW-GW相互作用的时空格局及其对污染物途径的影响。在低流量（2022年11月，T1）、正常流量（2023年5月，T2）和高流量（2023年8月，T3）期间进行了三次采样活动。结果表明，虽然水体以Ca-HCO₃型为主，但地球化学和同位素特征显示了高度动态的交换过程。从上游到下游的同位素富集（δ18O从~−10‰到~−6.5‰）表明有明显的蒸发和混合作用。至关重要的是，SW-GW相互作用为硝酸盐（NO₃−）等污染物创造了波动的途径。在T1干旱/灌溉季节，农业广泛的地下水抽取逆转了当地的水力梯度，减少了河流对地下水的补给，并诱导高硝酸盐地下水排放到河流中，地下水NO₃−浓度高达42.5 mg/L。相关分析表明，对补给比的优势控制因素有季节变化，从旱季的耕地（r = - 0.53）和森林（r = 0.49）到丰季的人口密度（r = - 0.26）和裸地（r = 0.35）。这些发现揭示了一个概念框架，其中季节性人类活动（例如，灌溉与城市径流）积极地改变了地表和地下系统之间污染物交换途径的方向和大小。本研究强调了对SW-GW资源进行综合动态管理的必要性，以减轻全球人为主导的农业集水区的污染风险。

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引用次数: 0

Unified analytical framework for multi-dimensional solute transport in fractured porous media 裂隙多孔介质中多维溶质输运的统一分析框架

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-10 DOI: 10.1016/j.jconhyd.2025.104793

V.G. Rumynin , L.N. Sindalovskiy

In this paper, we summarize solutions derived previously for solute transport through fractured porous media in a simplified layered setting, extending them to account for the diversity of the fracture–matrix mass transfer models, multi-dimensionality of the hydrodynamic dispersion in the fracture domain, the geometry of contamination sources (conceptualized as point, linear, plane, or parallelepiped) containing sorbed and decaying chemicals with typical inlet boundary conditions. Thus, a new analytical solution for the concentration field was derived. This solution unifies many existing approaches and models and enables the prediction of dual-porosity media behavior under new configurations of initial–boundary conditions and mass-transfer conceptualizations in the fracture–matrix system, considering the solute transport problem in an extended physical setting. The analysis was based on the dual-continuum approach for groundwater flow and solute transport in fractured geological media with a periodic matrix block arrangement, employing a method that decouples the complex solute transport by expressing the general solution of the ADEs in a convolution integral form. We verified the suggested approach and new analytical solutions against the previously published mass transport solutions related to homogeneous and dual-porosity systems.

在本文中，我们总结了先前在简化的分层设置中推导出的溶质通过裂缝多孔介质的解决方案，并将其扩展到考虑裂缝基质传质模型的多样性、裂缝域中流体动力弥散的多维性、含有吸附和衰变化学物质的污染源（概念为点、线、面或平行六面体）的几何形状和典型的入口边界条件。由此导出了一种新的浓度场解析解。该解决方案统一了许多现有的方法和模型，能够在初始边界条件和裂缝基质系统传质概念的新配置下预测双重孔隙介质的行为，同时考虑到扩展物理环境中的溶质输运问题。本文基于双连续体方法分析了具有周期性基质块体排列的裂缝性地质介质中地下水流动和溶质运移，采用了一种将ADEs通解解为卷积积分形式的方法来解耦复杂溶质运移。我们验证了建议的方法和新的分析解与先前发表的有关均匀和双重孔隙系统的质量输运解。

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引用次数: 0

Identification and assessment of urban groundwater pollution based on Monte Carlo health risk modeling and self-organizing map (SOM) 基于蒙特卡罗健康风险模型和自组织图的城市地下水污染识别与评价

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-10 DOI: 10.1016/j.jconhyd.2025.104807

Di Kang , Qizhi Hu , Hailong Qin , Hao Chen , Xiaoyu Xu , Xianming Xie , Xiang Ren , Xinyuan Zhang , Bingbing Cao , Chih-Huang Weng , Kai Liu , Na Liu

With the acceleration of urbanization, groundwater quality is severely threatened, posing health risks to public health and the environment. In reality, the highly heterogeneous geological background and hydrochemical relationships not only increase the difficulty in identifying pollution, but also pose significant challenges in groundwater risk prevention and control. Taking Guangzhou, a megacity in the bustling Pearl River Delta, as the research object, this study leverages the ability of machine learning to mine complex data and the advantage of Monte Carlo simulation in quantifying random uncertainties to deeply analyze the driving factors, pollution sources, and potential health risks of urban groundwater chemistry. Through the SOM model, a cluster analysis was conducted on 107 groundwater samples, resulting in the classification of 5 distinct water chemical groups with significant characteristics (Clusters I - V). Among them, human activities (domestic pollution) have a significant impact on groundwater chemistry mainly in Cluster I (a total contribution of 52.9 %). Manganese (Mn) and nitrate (NO₃⁻) pose non-carcinogenic risks, with the highest risks observed for Mn in Cluster II and NO₃⁻ in Cluster III. Monte Carlo simulation indicates that the overall health risk in the region is low, with only 1.3 % of children potentially exposed to high HI conditions. This study provides valuable insights for the precision prevention, control, and risk management of complex groundwater pollution in cities such as those in the Pearl River Delta.

随着城市化进程的加快，地下水水质受到严重威胁，对公众健康和环境构成健康风险。在现实中，高度非均匀的地质背景和水化学关系不仅增加了污染识别的难度，也给地下水风险防控带来了重大挑战。本研究以繁华的珠江三角洲特大城市广州为研究对象，利用机器学习对复杂数据的挖掘能力和蒙特卡罗模拟量化随机不确定性的优势，深入分析城市地下水化学的驱动因素、污染源和潜在健康风险。通过SOM模型对107份地下水样本进行聚类分析，划分出5个具有显著特征的水化学类群（聚类I - V）。其中，人类活动（生活污染）对地下水化学的影响主要集中在第一类，总贡献率为52.9%。锰（Mn）和硝酸盐（NO3−）具有非致癌风险，其中锰（Mn）在第二类中风险最高，NO3−在第三类中风险最高。蒙特卡罗模拟表明，该地区的总体健康风险较低，只有1.3%的儿童可能暴露于高HI条件下。该研究为珠江三角洲等城市复杂地下水污染的精准防控和风险管理提供了有价值的见解。

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引用次数: 0

Construction of an efficient synergistic catalytic system using DBD plasma and Fe-TiO2-rGO/HCP catalytic coating for ofloxacin removal DBD等离子体与Fe-TiO2-rGO/HCP催化涂层协同去除氧氟沙星体系的构建

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-10 DOI: 10.1016/j.jconhyd.2025.104791

Ming Li , Liang Guo , Yimo Zhao , Shanshan Huang , Ruofei Jia , Lijiao Zheng , Yongyang Chen , Shanping Li

An efficient synergistic catalytic system was constructed by combining a Fe-rGO-TiO₂ coating on honeycomb ceramic plates (HCP) with dielectric barrier discharge (DBD) plasma. The catalyst coating was comprehensively characterized, and its structural and morphological characteristics, chemical bond state, optical properties, and catalytic activity were systematically analyzed. The results show that by doping TiO₂ with Fe and graphene, the catalytic performance of TiO₂ can be enhanced by refining its grains and increasing the specific surface area. Ofloxacin (OFLX) was the target pollutant to evaluate the catalytic activity. The effects of initial pH, electrolyte concentration, and current density on OFLX degradation were analyzed. Compared with the single DBD plasma system, the catalytic ability of the constructed synergistic catalytic system was significantly improved. Under the optimal initial conditions, the Fe-rGO-TiO₂-DBD synergistic system achieved a 99.98 % OFLX degradation rate and enhanced energy output after 60 min of reaction. The measurements of liquid H₂O₂ and O₃ in the system and free-radical scavenging experiments proved that the synergistic method can increase the production of active substances. LC-MS analysis and theoretical calculations were used to propose possible OFLX degradation pathways and identify intermediates. Comprehensive toxicity analysis showed that intermediate products exhibited progressively lower toxicity. Finally, the comprehensive mechanism of DBD synergistic Fe-rGO-TiO₂ catalytic degradation of OFLX was summarized.

将蜂窝陶瓷板（HCP）表面的Fe-rGO-TiO2涂层与介质阻挡放电（DBD）等离子体结合，构建了一种高效的协同催化体系。对催化剂涂层进行了全面表征，系统分析了其结构形态特征、化学键态、光学性能和催化活性。结果表明，在TiO2中掺杂Fe和石墨烯，可以细化TiO2的晶粒，提高TiO2的比表面积，从而提高TiO2的催化性能。以氧氟沙星（OFLX）为目标污染物评价其催化活性。分析了初始pH、电解液浓度和电流密度对OFLX降解的影响。与单DBD等离子体体系相比，所构建的协同催化体系的催化能力显著提高。在最佳初始条件下，Fe-rGO-TiO2-DBD协同体系的OFLX降解率达到99.98%，反应60 min后能量输出增加。系统中液体H2O2和O3的测定和自由基清除实验证明，协同方法可以增加活性物质的产生。采用LC-MS分析和理论计算提出了可能的OFLX降解途径并鉴定了中间体。综合毒性分析表明，中间产物的毒性逐渐降低。最后总结了DBD协同Fe-rGO-TiO2催化降解OFLX的综合机理。

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引用次数: 0