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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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Nonlinear Impact Damage Evolution of Charpy Type and Analysis of Its Key Influencing Factors

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 254-264页

作者： Jianfeng Mao Qian Xu Jiadong Yang Chi Cao Dasheng Wang fengping Zhong Mingya Chen Institute of Process Equipment and Control Engineering Zhejiang University of TechnologyHangzhou 310032China Taizhou Key Laboratory of Advanced Manufacturing Technology Taizhou InstituteZhejiang University of TechnologyTaizhou 318014China State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment Shenzhen 518172China Zhejiang Academy of Special Equipment Science Hangzhou 310020China Suzhou Nuclear Power Research Institute Suzhou 215004China

The current research of Charpy impact mainly focuses on obtaining the ductile brittle transition temperature of materials by experiments.Compared with experiments,numerical simulation can study many problems with harsh conditions.However,there are still few studies on the influence of geometric factors such as side grooves.In this paper,the geometry of standard Charpy impact test is designed.Specimens with different widths and side grooves are tested.The finite element model of Charpy impact was established by ABAQUS software.Use test results and simulation results to verify each other.The effects of sample width,side groove depth and side groove bottom fillet on the impact fracture resistance of the sample were studied.The results show that the specimen width is positively correlated with the impact toughness of the specimen.The side groove greatly reduces the impact toughness of the material;the toughness of side groove decreases with the increase of depth;the fracture toughness of side groove decreases with the increase of fillet at the bottom of side groove.The proportion of toughness energy to impact energy of samples was analyzed.The results show that the toughness energy accounts for about 70%of the impact energy of the sample,which has little to do with the geometric characteristics of the sample.This study presents a reliable method for studying Charpy impact tests.The influence of geometric parameters is obtained,which provides a reference method for the study of impact toughness of high toughness materials.

关键词： Johnson-Cook model Impact toughness Charpy impact

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Metal-organic frameworks based single-atom catalysts for advanced fuel cells and rechargeable batteries

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Journal of Energy Chemistry 2023年第5期80卷 501-534,I0012页

作者： Yifei Wu Peng Hu fengping xiao xiaoting Yu Wenqi Yang Minqi Liang Ziwei Liang Aixin Zhu College of Chemistry and Chemical Engineering Yunnan Normal UniversityKunming 650500YunnanChind School of Energy and Environment Science Yunnan Normal UniversityKunming 650500.YunnanChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China School of Environment and Chemical Engineering Zhaoqing UniversityZhaoqing 526061GuangdongChina

The next-generation energy storage systems such as fuel cells,metal-air batteries,and alkali metal(Li,Na)-chalcogen(S,Se)batteries have received increasing attention owing to their high energy density and low cost.However,one of the main obstacles of these systems is the poor reaction kinetics in the involved chemical reactions.Therefore,it is essential to incorporate suitable and efficient catalysts into the cell.These years,single-atom catalysts(SACs)are emerging as a frontier in catalysis due to their maximum atom efficiency and unique reaction selectivity.For SACs fabrication,metal-organic frameworks(MOFs)have been confirmed as promising templates or precursors due to their high metal loadings,structural adjustability,porosity,and tailorable catalytic site.In this review,we summarize effective strategies for fabricating SACs by MOFs with corresponding advanced characterization techniques and illustrate the key role of MOFs-based SACs in these batteries by explaining their reaction mechanisms and challenges.Finally,current applications,prospects,and opportunities for MOFs-based SACs in energy storage systems are discussed.

关键词： Metal-organic frameworks Single-atom catalysts Rechargeable batteries Electrocatalysts Coordination configuration

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Microbially-mediated formation of Ca-Fe carbonates during dissimilatory ferrihydrite reduction:Implications for the origin of sedimentary ankerite

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Science China Earth Sciences 2024年第1期67卷 208-221页

作者： Deng LIU Jinpeng CAO Shanshan YANG Yating YIN Pengcong WANG Dominic PAPINEAU Hongmei WANG Xuan QIU Genming LUO Zongmin ZHU fengping WANG State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China School of Environmental Studies China University of GeosciencesWuhan 430074China London Centre for Nanotechnology University College LondonLondon WC1H 0AHUK Department of Earth Sciences University College LondonLondon WC1E 6BTUK Center for Planetary Sciences University College London and Birkbeck College LondonLondon WC1E 6BTUK State Key Laboratory of Microbial Metabolism State Key Laboratory of Ocean EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The origin of sedimentary dolomite has become a long-standing problem in the Earth Sciences.Some carbonate minerals like ankerite have the same crystal structure as dolomite,hence their genesis may provide clues to help solving the dolomite problem.The purpose of this study was to probe whether microbial activity can be involved in the formation of ankerite.Bio-carbonation experiments associated with microbial iron reduction were performed in batch systems with various concentrations of Ca^(2+)(0–20 mmol/L),with a marine iron-reducing bacterium Shewanella piezotolerans WP3 as the reaction mediator,and with lactate and ferrihydrite as the respective electron donor and acceptor.Our biomineralization data showed that Ca-amendments expedited microbially-mediated ferrihydrite reduction by enhancing the adhesion between WP3 cells and ferrihydrite particles.After bioreduction,siderite occurred as the principal secondary mineral in the Ca-free systems.Instead,Ca-Fe carbonates were formed when Ca^(2+)ions were present.The CaCO_(3) content of microbially-induced Ca-Fe carbonates was positively correlated with the initial Ca2+concentration.The Ca-Fe carbonate phase produced in the 20 mmol/L Ca-amended biosystems had a chemical formula of Ca_(0.8)Fe_(1.2)(CO_(3))_(2),which is close to the theoretical composition of ankerite.This ankeritelike phase was nanometric in size and spherical,Ca-Fe disordered,and structurally defective.Our simulated diagenesis experiments further demonstrated that the resulting ankerite-like phase could be converted into ordered ankerite under hydrothermal conditions.We introduced the term“proto-ankerite”to define the Ca-Fe phases that possess near-ankerite stoichiometry but disordered cation arrangement.On the basis of the present study,we proposed herein that microbial activity is an important contributor to the genesis of sedimentary ankerite by providing the metastable Ca-Fe carbonate precursors.

关键词： Ankerite Proto-ankerite Microbial iron reduction Dolomite problem Mineral transformation

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Whyand how tousethe SeqCode

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mLife 2024年第1期3卷 1-13页

作者： Wiliam B.Whitman Maria Chuvochina Brian P.Hedlund Konstantinos T.Konstantinidis Marike Palmer Luis M.Rodriguez-R lain Sutcliffe fengping Wang Deparment of Microbioogy University of GeorgiaAthensGeorgiaUAA Schoolof Chemistry and Molecular Biosciences Australian CentreforEogenomicsThe Universty of QueenslandSt LuciaAustralia University of Nevada Las Vegas Las VegasNevadaUSA Schol of Civil and Environmental Engineering and School of Biological SciencesGeorgia Institute of TechnologyAtlantaGeorgiaUSA Department of Microbiology University of ManitobaWinnipegManitobaCanada School of Life Sciences University of Nevada Las VegasLas VegasNevadaUSA Department of Microbiology and Digital Science Center(DiSC) University of InnsbruckInnsbruckAustria Faculty of Health&Life Sciences Northumbria UniversityNewcastle upon TyneUK School of Oceanography International Center for Deep Life InvestigationShanghai Jiao Tong UniversityShanghaiChina

The SeqCode,formally called the Code of Nomenclature of Prokaryotes Described from Sequence Data,is a new code of nomenclature in which genome sequences are the nomenclatural types for the names of prokaryotic species.While similar to the International Code of Nomenclature of Prokaryotes(ICNP)in structure and rules of priority,it does not require the deposition of type strains in international culture collections.Thus,it allows for the formation of permanent names for uncultured prokaryotes whose nearly complete genome sequences have been obtained directly from environmental DNA as well as other prokaryotes that cannot be deposited in culture collections.Because the diversity of uncultured prokaryotes greatly exceeds that of readily culturable prokaryotes,the SeqCode is the only code suitable for naming the majority of prokaryotic species.The start date of the SeqCode was January 1,2022,and the online Registry(https://seqco.del)was created to ensure valid publication of names.The SeqCode recognizes all names validly published under the ICNP before 2022.After that date,names validly published under the SeqCode compete with ICNP names for priority.As a result,species can have only one name,either from the SeqCode or ICNP,enabling effective communication and the creation of unified taxonomies of uncultured and cultured prokaryotes.The SeqCode is administered by the SeqCode Committee,which is comprised of the SeqCode Community and elected administrative components.Anyone with an interest in the systematics of prokaryotes is encouraged to join the SeqCode Community and participate in the development of this resource.

关键词： genome sequences metagenome-assembled genomes nomenclature SeqCode

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不同防风设施过渡段接触网风场特性分析

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铁道工程学报 2024年第2期41卷 80-85页

作者：郭凤平中铁第一勘察设计院集团有限公司西安710043

研究目的:大风经不同防风设施过渡段后形成涡流区,在接触网及承力索附近形成大风增速区,加大接触网的风偏和振动,对接触网的安全性、稳定性及抗疲劳性产生更大影响。为研究不同防风设施过渡段接触网处的风场特性,根据兰新高铁明洞与路... 详细信息

研究目的:大风经不同防风设施过渡段后形成涡流区,在接触网及承力索附近形成大风增速区,加大接触网的风偏和振动,对接触网的安全性、稳定性及抗疲劳性产生更大影响。为研究不同防风设施过渡段接触网处的风场特性,根据兰新高铁明洞与路基挡风墙防风过渡段的典型结构,基于数值计算及风洞试验,对列车在隧道、明洞、挡风屏和挡风墙等不同防风设施运行时的接触网处风场特性进行研究。研究结论:(1)不同线路结构风速变化规律基本一致,来流风速经过车身绕流作用,风速先急剧增大,随着列车逐渐远离监测点,风速减小并最后趋于稳定;(2)防风设施过渡段承力索处风速较接触线处大;(3)不同防风设施过渡段隧道口及隧道与路基挡风墙过渡段风速峰值较大,运行时应给予重点关注,建议采用弹性定位器等措施,改善弓网的运行状态;(4)本研究成果可为防风设施过渡段的接触网设计提供依据。

关键词：防风过渡段风场特性风洞试验接触网风致响应

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大跨径斜拉桥施工阶段临时抗风措施对比分析

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铁道工程学报 2024年第1期41卷 39-44,52页

作者：刘旭政曾健峰王丰平华东交通大学轨道交通基础设施性能监测与保障国家重点实验室南昌330013 中国市政工程中南设计研究总院有限公司武汉430010 浙江数智交院科技股份有限公司杭州310006

研究目的:大跨径斜拉桥在最大双悬臂施工状态下结构刚度较小,对风荷载引起的结构风致振动响应较为敏感。本文以受沿海台风影响区域的一座主跨316 m斜拉桥为研究对象,根据风洞试验确定主梁的气动三分力系数,对比分析不同风缆布置方案与... 详细信息

研究目的:大跨径斜拉桥在最大双悬臂施工状态下结构刚度较小,对风荷载引起的结构风致振动响应较为敏感。本文以受沿海台风影响区域的一座主跨316 m斜拉桥为研究对象,根据风洞试验确定主梁的气动三分力系数,对比分析不同风缆布置方案与不同临时墩布置方式对大桥风致响应控制效果的影响。研究结论:(1)增设临时风缆可使主梁竖弯基频提高22.0%~32.5%,对结构自身的扭转基频影响效果不显著;临时风缆对主梁竖向位移和主塔顺桥向位移控制有一定作用,固定位置在主梁最大悬臂长度的80%~90%范围内效果较好;(2)临时墩的抗风减振效果显著优于临时风缆,临时墩的设置使主梁悬臂端竖向位移响应降低了53.5%~65.5%,对主梁悬臂根部的顺桥向弯矩与横桥向弯矩的控制效果较为明显,降幅11.7%~58.8%;(3)在选择桥梁临时抗风措施时,需综合考虑抗风需求、施工条件、施工风险和经济性;(4)本研究成果可为大跨度斜拉桥临时抗风措施的选择提供参考。

关键词：斜拉桥最大双悬臂施工状态临时墩临时风缆风致响应

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流域国水资源短缺性组合评价模型及应用

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经济与管理评论 2024年第3期40卷 45-58页

作者：吴骁远吴凤平江苏开放大学商学院江苏南京210036 河海大学商学院江苏南京211100

随着全球淡水资源的日益短缺,跨境水资源分配的不公平性已成为引发流域国水资源冲突的主要根源之一。首先,通过考察美、非、亚、欧典型跨境河流,梳理流域国水资源短缺性的影响因素。其次,针对跨境河流的特点,构建流域国水资源短缺性评价... 详细信息

随着全球淡水资源的日益短缺,跨境水资源分配的不公平性已成为引发流域国水资源冲突的主要根源之一。首先,通过考察美、非、亚、欧典型跨境河流,梳理流域国水资源短缺性的影响因素。其次,针对跨境河流的特点,构建流域国水资源短缺性评价的8个评价指标,包括人均水资源量、产水模数等反映水资源自然禀赋和水资源供给能力的指标,总用水量、农业用水量占比等反映水资源需求状况的指标,以及内部可再生淡水资源等反映替代水源的指标。再次,构建流域国水资源短缺性指数测度模型,在通过加性加权法、物元关联法、改进TOPSIS法分别进行评价的基础上,运用基于循环修正的组合评价模型集成评价结果,并通过Kendall协和系数法开展事前一致性检验,通过Spearman法开展事后一致性检验。最后,结合澜湄流域开展应用研究,测算澜湄流域内六个流域国的水资源短缺性状况,验证模型的可行性和实用性。

关键词：跨境水资源流域国水资源短缺性

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Corrosion behavior of HVOF Inconel 625 coating in the simulated marine environment

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China Welding 2024年第1期33卷 46-51页

作者：彭超钟丰平袁梦谢世杰王学斌 National Quality Inspection and Testing Center of Special Metal Structural Materials Zhejiang Academy of Special Equipment ScienceHangzhou 310020China Key Laboratory of Special Equipment Safety Testing Technology of Zhejiang Province Hangzhou 310020China Zhejiang-Ukraine Joint Laboratory for Materials and Welding Testing Technology Hangzhou 310020China

High velocity oxygen fuel(HVOF)spraying process is commonly used to produce superalloy coatings.Inconel 625 coating was prepared on Q235B low carbon steel by HVOF.A series of experiments were conducted to examine the surface and corrosion resistance properties of Inconel 625 HVOF coating.In this paper,potentiodynamic polarization tests and electrochemical impedance spectroscopy(EIS)tests were carried out to evaluate the corrosion resistance of Inconel 625 coating under simulated marine environment.The experiment-al results showed that Inconel 625 coating revealed low porosity and desired coating thickness.Shift in the corrosion potential(E_(corr))to-wards the noble direction combined with much low corrosion current density(i_(corr))indicating a significant improvement of HVOF Inconel 625 coating compared with the substrate.

关键词： high velocity oxygen fuel(HVOF) Inconel 625 coating marine environment corrosion

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高效液相色谱-串联质谱法测定玉米蛋白粉中黄曲霉毒素B 1测量不确定度评定

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中国粮油学报 2024年第5期39卷 181-188页

作者：王鑫张凤枰杨娟四川威尔检测技术股份有限公司成都610041 通威股份有限公司农业农村部水产畜禽营养与健康养殖重点实验室成都610093 通威股份有限公司四川省水产健康养殖重点实验室成都610093

采用GUM法和Top-down法对高效液相-串联质谱法测定玉米蛋白粉中的黄曲霉毒素B 1测量不确定度进行评定。通过比较2种方法的评定过程和评定结果发现,Top-down法在简化评定步骤、保证评定结果可靠性的前提下,能够充分利用实验室检测数据和... 详细信息

采用GUM法和Top-down法对高效液相-串联质谱法测定玉米蛋白粉中的黄曲霉毒素B 1测量不确定度进行评定。通过比较2种方法的评定过程和评定结果发现,Top-down法在简化评定步骤、保证评定结果可靠性的前提下,能够充分利用实验室检测数据和质量控制数据,引入检测人员变动、检测仪器更换等带来的不确定度,是一种客观、高效的不确定度评定方法,为饲料中黄曲霉毒素B 1检测数据准确溯源提供参考。

关键词：高效液相色谱-串联质谱法测量不确定度 GUM法 Top-down法黄曲霉毒素B 1

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