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Iodine enrichment in the groundwater in South China and its hydrogeochemical control

Journal of Environmental Sciences 2024年第8期142卷 226-235页

作者： Fengping Zhou Qianting Xu yuyun chen Weihua Zhang Rongliang Qiu Guangdong Provincial Key Laboratory of Environmental Pollution and Remediation Technology Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil RemediationSchool of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Shenzhen Research Institute Sun Yat-sen UniversityShenzhen 518057China Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety School of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China

In North China,iodine-rich groundwater has been extensively studied,but few in South China.This study aimed to investigate the characteristics of iodine-rich groundwater in South China and identify potential contamination sources.The results revealed that the average concentration of iodine in groundwater was 890μg/L,with a maximumconcentration of 6350μg/L,exceeding the permitted levels recommended by the World Health Organization(5–300μg/L).Notably,the enrichment of iodide occurred in acidic conditions(pH=6.6)and a relatively low Eh environment(Eh=198.4 mV).Pearson correlation and cluster analyses suggested that the enrichment of iodide could be attributed to the intensified redox process involving Mn(II),iodine(I_(2)),or iodate(IO_(3)^(−))in the soil.The strong affinity between Mn(II)and I_(2)/IO_(3)^(−)facilitated their interaction,resulting in the formation and mobilization of I^(−)from the soil to the groundwater.Leaching experiments further confirmed that reducing substances(such as sodium sulfides,ascorbic acids,and fulvic acids)in the soil with low dissolved oxygen(DO)levels(3.8 mg/L)promoted the oxidation of I^(−)into I_(2)or IO_(3)^(−),leading to its stabilization.This research provides new insights into the characteristics and mechanisms of I^(−)enrichment in groundwater in South China,and emphasizes the significance of the redox reactions involving Mn(II)and I_(2)/IO_(3)^(−),as well as the influence of soil properties in regulating the occurrence and transportation of iodine species within groundwater systems.

关键词： Iodine enrichment Acid environment Groundwater South China Manganese

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Optimal maneuvering strategy of spacecraft evasion based on angles-only measurement and observability analysis

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Journal of Systems Engineering and Electronics 2023年第1期34卷 172-184页

作者： ZHANG Yijie WANG Jiongqi HOU Bowen WANG Dayi chen yuyun College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073China Beijing Institute of Spacecraft System Engineering Beijing 100190China School of Mathematics and Big Data Foshan UniversityFoshan 528000China

Spacecraft orbit evasion is an effective method to ensure space safety. In the spacecraft’s orbital plane, the space non-cooperate target with autonomous approaching to the spacecraft may have a dangerous rendezvous. To deal with this problem, an optimal maneuvering strategy based on the relative navigation observability degree is proposed with angles-only measurements. A maneuver evasion relative navigation model in the spacecraft’s orbital plane is constructed and the observability measurement criteria with process noise and measurement noise are defined based on the posterior Cramer-Rao lower bound. Further, the optimal maneuver evasion strategy in spacecraft’s orbital plane based on the observability is proposed. The strategy provides a new idea for spacecraft to evade safety threats autonomously. Compared with the spacecraft evasion problem based on the absolute navigation, more accurate evasion results can be obtained. The simulation indicates that this optimal strategy can weaken the system’s observability and reduce the state estimation accuracy of the non-cooperative target, making it impossible for the non-cooperative target to accurately approach the spacecraft.

关键词： rendezvous evasion orbit maneuver angles-only measurement observability degree posterior Cramer-Rao lower bound

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TOA positioning algorithm of LBL system for underwater target based on PSO

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系统工程与电子技术:英文版 2023年第5期34卷 1319-1332页

作者： XING Yao WANG Jiongqi HE Zhangming ZHOU Xuanying chen yuyun PAN Xiaogang College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073China School of Mathematics and Big Data Foshan UniversityFoshan 528000China College of Systems Engineering National University of Defense TechnologyChangsha 410073China

For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlinear iteration.However,due to the complex underwater environment,the sound speed changes with time and space,and then the acoustic propagation path is actually a curve,which inevitably causes some errors to the traditional distance intersection positioning algorithm.To reduce the position error caused by the uncertain underwater sound speed,a new time of arrival(TOA)intersection underwater positioning algorithm of LBL system is proposed.Firstly,combined with the vertical layered model of the underwater sound speed,an implicit positioning model of TOA intersection is constructed through the constant gradient acoustic ray tracing.And then an optimization function based on the overall TOA residual square sum is advanced to solve the position parameters for the underwater target.Moreover,the particle swarm optimization(PSO)algorithm is replaced with the tra-ditional nonlinear least square method to optimize the implicit positioning model of TOA intersection.Compared with the traditional distance intersection positioning model,the TOA intersec-tion positioning model is more suitable for the engineering practice and the optimization algorithm is more effective.Simulation results show that the proposed methods in this paper can effectively improve the positioning accuracy for the underwater target.

关键词： long baseline(LBL)positioning system sound speed profile constant gradient acoustic ray tracing time of arrival(TOA)intersection model particle swarm optimization(PSO)

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Mitigating the Reconstruction of Metal Sulfides for Ultrastable Oxygen Evolution at High Current Density

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CCS Chemistry 2024年第1期6卷 137-148页

作者： Shuai Niu Tang Tang Yuanju Qu yuyun chen Hao Luo Hui Pan Wen-Jie Jiang Jianan Zhang Jin-Song Hu Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Nanostructure and NanotechnologyInstitute of ChemistryChinese Academy of SciencesBeijing 100190 Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao SAR 999078 Department of Chemical Engineering University of MelbourneParkvilleVictoria 3010 College of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001 School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049 Dalian National Laboratory for Clean Energy Dalian 116023

Metal sulfides are emerging highly active electrocatalysts for the oxygen evolution reaction(OER),but still suffer from the instability caused by their inevitable reconstruction,especially at industrial-level current density.Here,it is discovered that Fe-incorporated Ni3S2 nanowires can deliver extraordinary durability with an ultralow potential degradation rate of 0.006 mV/h in alkaline electrolytes made with fresh water and seawater at a benchmark of 500 mA cm^(-2) while meeting the industrial activity requirement for overpotential less than 300 mV(290 mV).Systematic experiments and theoretical simulations suggest that after forming the S-doped NiFeOOH shell to boost intrinsic activity,Fe incorporation effectivelymitigates the reconstruction of the Ni_(3)S_(2) nanowire core by restraining Ni oxidation and S dissolution,justifying the performance.This work highlights the significance of circumventing reconstruction and provides a strategy to explore practical chalcogenides-based OER electrocatalysts.

关键词： oxygen evolution reaction sulfur-doped NiFeOOH NiFe sulfides nanowire ultrastable high current density

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Optimization of synergistic energy storage density and efficiency for eco-friendly (Na_(0.5)Bi_(0.5))_(0.6)Sr_(0.4)TiO_(3)-based relaxor ferroelectric ceramics

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Journal of Materiomics 2021年第4期7卷 869-878页

作者： Hu Di Pan Zhongbin Wu Lukang Yang Fan Tang Luomeng Zhao Jinghao Shen Yihao chen yuyun Li Peng Zhai Jiwei Liu Jinjun School of Materials Science and Chemical Engineering Ningbo UniversityNingboZhejiang315211China Guangxi Key Laboratory of Chemistry and Engineering of Forest Products Guangxi University for NationalitiesNanning530006China School of Materials Science and Engineering Liaocheng UniversityLiaocheng252059China School of Materials Science&Engineering Tongji University4800 Caoan RoadShanghai201804China

Inspired by increasing demand of advanced pulsed power capacitors,the development of lead-free dielectric ceramic capacitors with high energy storage density and temperature-insensitive performance are extremely crucial.Herein,the lead-free relaxor ferroelectric ceramics based on(1-x)(Na_(0.5)Bi_(0.5))0.6Sr_(0.4)TiO_(3-x)Sr_(0.7)La_(0.2)ZrO_(3)[abbreviated as(1-x)NBST-xSLZ]are prepared by the solid-state reaction route.The large recoverable energy density(Wrec)of 3.45 J/cm^(3) and efficiency(h)of 90.1%are simultaneously realized in 0.86NBST-0.14SLZ ceramic due to increased breakdown strength.Furthermore,both the Wrec and h of 0.86NBST-0.14SLZ ceramic display superior of thermal stability(20e180C),frequency stability(1e1000 Hz),and cycle stability(10^(4))within a satisfactory range of variation.In addition,the 0.86NBST-0.14SLZ ceramic can also achieve a large current density(CD)of 625 A/cm^(2),an ultrahigh power density(PD)of 50 MW/cm^(3) and a fast discharge rate(t0.90)of 160.8 ns at 160 kV/cm.These results demonstrate that the 0.86NBST-0.14SLZ ceramic could be a highly competitive and ecofriendly relaxor ferroelectric material for next-generation pulsed power capacitors.

关键词： Lead-free ceramics Energy storage density (Na_(0.5)Bi_(0.5))_(0.6)Sr_(0.4)TiO_(3) Thermal stability Power density

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Corrosion engineering boosting bulk Fe_(50)Mn_(30)Co_(10)Cr_(10)high-entropy alloy as high-efficient alkaline oxygen evolution reaction electrocatalyst

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Journal of Materials Science & Technology 2022年第14期109卷 267-275页

作者： Pengfei Zhou Dong Liu yuyun chen Mingpeng chen Yunxiao Liu Shi chen Chi Tat Kwok Yuxin Tang Shuangpeng Wang Hui Pan Institute of Applied Physics and Materials Engineering University of Macao999078Macao Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of Macao999078Macao Department of Electromechanical Engineering Faculty of Science and TechnologyUniversity of Macao999078Macao College of Chemical Engineering Fuzhou UniversityFuzhou 350116China

Oxygen evolution reaction(OER)is a critical process in electrocatalytic water splitting.However,the development of low-cost,highly efficient OER electrocatalysts by a simple method that can be used for industrial application on a large scale is still a huge challenge.Recently,high entropy alloy(HEA)has acquired extensive attention,which may provide answers to the current dilemma.Here,we report bulk Fe_(50)Mn_(30)Co_(10)Cr_(10),which is prepared by 3D printing on a large scale,as electrocatalyst for OER with high catalytic performance.Especially,an easy approach,corrosion engineering,is adopted for the first time to build an active layer of honeycomb nanostructures on its surface,leading to ultrahigh OER performance with an overpotential of 247 mV to achieve a current density of 10 mA cm^(-2),a low Tafel slope of 63 mV dec^(-1),and excellent stability up to 60 h at 100 mA cm^(-2)in 1 M KOH.The excellent catalytic activity mainly originates from:(1)the binder-free self-supported honeycomb nanostructures and multi-component hydroxides,which improve intrinsic catalytic activity,provide rich active sites,and reduce interfacial resistance;and(2)the diverse valence states for multiple active sites to enhance the OER kinetics.Our findings show that corrosion engineering is a novel strategy to improve the bulk HEA catalytic performance.We expect that this work would open up a new avenue to fabricate large-scale HEA electrocatalysts by 3D printing and corrosion engineering for industrial applications.

关键词： Electrocatalysis High entropy alloy Corrosion engineering Self-supporting Oxygen evolution reaction

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Insight into coupled Ni-Co dual-metal atom catalysts for efficient synergistic electrochemical CO_(2)reduction

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Journal of Energy Chemistry 2023年第12期87卷 509-517,I0013页

作者： Qingchun Zhang Di Liu Yaping Zhang Zhiliang Guo Minpeng chen yuyun chen Bo Jin Yingze Song Hui Pan State Key Laboratory of Environment-Friendly Energy Materials School of Materials and ChemistryTianfu Institute of Research and InnovationSouthwest University of Science and TechnologyMianyang 621010SichuanChina Institute of Applied Physics and Materials Engineering University of MacaoMacao 999078China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189JiangsuChina

The development of highly active,selective,and stable electrocatalysts can facilitate the effective implementation of electrocatalytic CO_(2)conversion into fuels or chemicals for mitigating the energy crisis and climate problems.Therefore,it is necessary to achieve the goal through reasonable material design based on the actuality of the operational active site at the molecular scale.Inspired by the stimulating synergistic effect of coupled heteronuclear metal atoms,a novel Ni-Co atomic pairs configuration(denoted as NiN_(3)?CoN_(3)-NC)active site was theoretically screened out for improving electrochemical CO_(2)reduction reaction(CO_(2)RR).The structure of NiN_(3)?CoN_(3)-NC was finely regulated by adjusting Zn content in the precursors Zn/Co/Ni-zeolite imidazolate frameworks(Zn/Co/Ni-ZIFs)and pyrolysis temperature.The structural features of NiN_(3)?CoN_(3)-NC were systematically confirmed by aberration-corrected HAADF-STEM coupled with 3D atom-overlapping Gaussian-function fitting mapping,XAFS,and XRD.The results of theoretical calculations reveal that the synergistic effect of Ni-Co atomic pairs can effectively promote the*COOH intermediate formation and thus the overall CO_(2)RR kinetic was improved,and also restrained the competitive hydrogen evolution reaction.Due to the attributes of Ni-Co atomic pairs configuration,the developed NiN_(3)?CoN_(3)-NC with superior catalytic activity,selectivity,and durability,with a high turnover frequency of 2265 h^(-1)at-1.1 V(vs.RHE)and maximum Faradaic efficiency of 97.7%for CO production.This work demonstrates the great potential of DACs as highly efficient catalysts for CO_(2)RR,provides a useful strategy to design heteronuclear DACs,exploits the synergistic effect of multiple metal sites to facilitate complex CO_(2)RR catalytic reactions,and inspires more efforts to develop the potential of DACs in various fields.

关键词： Coupled dual-metal atom catalysts CO_(2)reduction reaction Electrocatalysts Density functional theory

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DNA damage-mediated cellular senescence promotes hand-foot syndrome that can be relieved by thymidine prodrug

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Genes & Diseases 2023年第6期10卷 2557-2571页

作者： Bingxue Yang Xinran Xie Zhaoyu Wu Dazhao Lv Jiajun Hu yuyun chen Jiaxing Li Shuyue Luo Jiacheng Li Jie Luo Shiyi Zhang School of Pharmacy Shanghai Jiao Tong UniversityShanghai 200240China School of Pharmacy and School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Hand-foot syndrome(HFS)is a widely recognized dose-limiting cutaneous toxicity effect of fluoropyrimidine chemotherapy agents that impairs clinical benefits and treatment outcomes.Even though the cause and pathophysiology of HFS are relatively widely reported,how the toxicity of fluoropyrimidine translates into persistent inflammation has not been studied.Additionally,prevention and treatment strategies for HFS based on its mechanistic occurrence and development are scarce.In our study,we demonstrated that cGAS-STING signaling pathway-mediated cellular senescence played a critical role in the inflammatory reaction and provided a therapeutic solution for HFS.Mechanistically,DNA damage,as the primary cytotoxic cause,in keratinocytes induces cell cycle arrest,activates the cGAS-STING signaling pathway,and subsequently mediates cellular senescence,ultimately fueling a robust secondary inflammatory response that results in HFS.More importantly,the thymidine prodrug thymidine diacetate was proven to be effective in preventing HFS by compensating for thymidylate deficiency to facilitate the replication and repair of DNA and thus causing the escape from cellular senescence.These data highlight the importance of DNA damage-mediated cellular senescence in the etiology of HFS and provide a potential therapeutic anchor point for fluoropyrimidine-induced HFS.

关键词： Cellular senescence cGAS-STING Cutaneous toxicity DNA damage Fluoropyrimidine Hand-foot syndrome Keratinocytes Thymidine prodrug

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Remarkable synergistic effect in cobalt-iron nitride/alloy nanosheets for robust electrochemical water splitting

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Journal of Energy Chemistry 2022年第2期31卷 405-414页

作者： Mingpeng chen Di Liu Baoye Zi yuyun chen Dong Liu Xinyu Du Feifei Li Pengfei Zhou Ye Ke Jielei Li Kin Ho Lo Chi Tat Kwok Weng Fai Ip Shi chen Shuangpeng Wang Qingju Liu Hui Pan Institute of Applied Physics and Materials Engineering University of MacaoMacaoChina Yunnan Key Laboratory for Micro/Nano Materials&Technology National Center for International Research on Photoelectric and Energy MaterialsSchool of Materials and EnergyYunnan UniversityKunming 650091YunnanChina Department of Electromechanical Engineering Faculty of Science and TechnologyUniversity of MacaoMacaoChina Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of MacaoMacaoChina

Design and synthesis of noble-metal-free bifunctional catalysts for efficient and robust electrochemical water splitting are of significant importance in developing clean and renewable energy sources for sustainable energy consumption.Herein,a simple three-step strategy is reported to construct cobalt-iron nitride/alloy nanosheets on nickel foam(CoFe-NA/NF)as a bifunctional catalyst for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The electrocatalyst with optimized composition(CoFe-NA2/NF)can achieve ultralow overpotentials of 73 mV and 250 mV for HER and OER,respectively,at a current density of 10 mA cm^(-2) in 1 M KOH.Notably,the electrolyzer based on this electrocatalyst is able to boost the overall water splitting with a cell voltage of 1.564 V to deliver 10 mA cm^(-2) for at least 50 h without obvious performance decay.Furthermore,our experiment and theoretical calculation demonstrate that the combination of cobalt-iron nitride and alloy can have low hydrogen adsorption energy and facilitate water dissociation during HER.In addition,the surface reconstruction introduces metal oxyhydroxides to optimize the OER process.Our work may pave a new pathway to design bifunctional catalysts for overall water splitting.

关键词： Bifunctional electrocatalyst Metal nitride/alloy nanocomposite Overall water splitting High performance

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In situ transformation of Cu2O@MnO2 to Cu@Mn（OH）2 nanosheet-on-nanowire arrays for efficient hydrogen evolution

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Nano Research 2018年第4期11卷 1798-1809页

作者： Li chen Xing Zhang Wenjie Jiang Yun Zhang Linbo Huang yuyun chen Yuguo Yang Li Li Jinsong Hu CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China School of Science Beijing Jiaotong University Beijing 100044 China University of Chinese Academy of Sciences Beijing 100049 China School of Chemistry and ChemicalEngineering Chongqing University Chongqing 400044 China

The development of new non-precious metal catalysts and understanding the origin of their activity for the hydrogen evolution reaction （HER） are essential for rationally designing highly active low-cost catalysts as alternatives to state-of-the-art precious metal catalysts. Herein, manganese oxide/hydroxide was demonstrated as a highly active electrocatalysts for the HER by fabricating MnO2 nanosheets coated with Cu2O nanowire arrays （Cu2O@MnO2 NW@NS） on Cu foam followed by an in situ chronopotentiometry （CP） treatment. It was discovered that the in situ transformation of Cu2O@MnO2 into Cu@Mn（OH）2 NW@NS by the CP treatment drastically boosted the catalytic activity for the HER due to an enhancement of its intrinsic activity. Together with the benefits from such （3D） core-sheU arrays for exposing more accessible active sites and efficient mass and electron transfers, the resulting Cu@Mn（OH）2 NW@NS exhibited excellent HER activity and outstanding durability in terms of a low overpotential of 132 mV vs. RHE at 10 mA/cm2, Overall, we expect these findings to generate new opportunities for the exploration of other Mn-based nanomaterials as efficient electrocatalysts and enable further understanding of their catalytic processes.

关键词： hydrogen evolutionreaction （HER）,water electrolysis,electrocatalysis,manganese oxides,manganese hydroxides

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