Browsing by Author "Lu, Ying"

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    Enhanced bioelectroremediation of heavy metal contaminated groundwater through advancing a self-standing cathode
    (Elsevier, 2024-06-01) Ali, Jafar; Zheng, Changhong; Lyu, Tao; Oladoja, Nurudeen Abiola; Lu, Ying; An, Wengang; Yang, Yuesuo
    Hexavalent chromium (Cr(VI)) contamination in groundwater poses a substantial global challenge due to its high toxicity and extensive industrial applications. While the bioelectroremediation of Cr(VI) has attracted huge attention for its eco-friendly attributes, its practical application remains constrained by the hydrogeochemical conditions of groundwater (mainly pH), low electron transfer efficiency, limitations in electrocatalyst synthesis and electrode fabrication. In this study, we developed and investigated the use of N, S co-doped carbon nanofibers (CNFs) integrated on a graphite felt (GF) as a self-standing cathode (NS/CNF-GF) for the comprehensive reduction of Cr(VI) from real contaminated groundwater. The binder free cathode, prepared through electro-polymerization, was employed in a dual-chamber microbial fuel cell (MFC) for the treatment of Cr (VI)-laden real groundwater (40 mg/L) with a pH of 7.4. The electrochemical characterization of the prepared cathode revealed a distinct electroactive surface area, more wettability, facilitating enhanced adsorption and rapid electron transfer, resulting in a commendable Cr(VI) reduction rate of 0.83 mg/L/h. The MFC equipped with NS/CNF-GF demonstrated the lowest charge transfer resistance (Rct) and generated the highest power density (155 ± 0.3 mW/m2) compared to control systems. The favorable electrokinetics for modified cathode led to swift substrate consumption in the anode, releasing more electrons and protons, thereby accelerating Cr(VI) reduction to achieve the highest cathodic coulombic efficiency (C.Eca) of80 ± 1.3 %. A similar temporal trend observed between Cr(VI) removal efficiency, COD removal efficiency, and C.Eca, underscores the effective performance of the modified electrode. The reusability of the binder free cathode, exemption from catholyte preparation and the absence of pH regulation requirements highlighted the potential scalability and applicability of our findings on a larger scale.
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    Nature-based stormwater management for aquifer recharge: exploring bioclogging-induced challenges
    (Elsevier, 2025-08-01) Wu, Yuhui; Lu, Ying; Yan, Zihan; Shi, Min; Wang, Qiandan; Lyu, Tao; Jia, Ruoyu; Huang, Ling; Chen, Zhiliang; Chen, Jianyu; Song, Xiaoming; Yang, Yuesuo
    Utilising excess urban stormwater to recharge groundwater can effectively mitigate the problems caused by the over-exploitation of subsurface environments while simultaneously making full use of valuable water resources. However, bioclogging can significantly reduce the efficiency of recharge projects in practical applications. This study is distinguished by its comprehensive consideration of unsaturated hydraulic conditions during stormwater recharge, which can influence microbial activities and the evolution of bioclogging, setting it apart from the predominant focus on saturated conditions in previous research. Microbial activity in the media became more vigorous under unsaturated conditions, and the cell volume decreased to 33–50 % of that under saturated conditions. Under unsaturated conditions, microbial EPS exhibited a curled morphology. At 60 % saturation, the contents of LB-EPS and polysaccharides increased by 141.23 and 187.47 μg/g sand, respectively, compared to saturated conditions. The reduction in saturation weakened microbial migration, promoted their deposition on the media surfaces, and reduced the non-uniformity of interlayer distribution. Simultaneously, unsaturated seepage conditions attenuated the effect of flow velocity (0.5–2 mL/min) changes on microbial migration and deposition. Bioclogging under unsaturated seepage conditions was governed by both EPS action and the EPS-bacterial interaction, with EPS secretion significantly influencing the degree of internal bioclogging development. This work contributes to a more comprehensive understanding of the bioclogging mechanisms under the unique hydrodynamic conditions of stormwater recharge, enabling more precise prevention and control of bioclogging during artificial stormwater recharge.