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how well does XAD resin extraction recover halogenated disinfection byproducts for comprehensive identification and toxicity testing?

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Journal of Environmental sciences 2022年第7期34卷 264-275页

作者： Xiaobin Liao Joshua M.Allen Caroline O.Granger susan D.richardson Department of Chemistry and Biochemistry University of South CarolinaColumbiaSouth Carolina 29208USA Institute of Municipal and Environmental Engineering College of Civil EngineeringHuaqiao UniversityFujian 361021China Currently at LanzaTech 535 Commerce DriveSopertonGeorgia 30457USA

halogenated disinfection byproducts(DBPs) are an unintended consequence of drinking water disinfection, and can have significant toxicity. XAD resins are commonly used to extract and enrich trace levels of DBPs for comprehensive, nontarget identification of DBPs and also for in vitro toxicity studies. however, XAD resin recoveries for complete classes of halogenated DBPs have not been evaluated, particularly for low, environmentally relevant levels(ng/L to low μg/L). Thus, it is not known whether levels of DBPs or the toxicity of drinking water might be underestimated. In this study, DAX-8/XAD-2 layered resins were evaluated, considering both adsorption and elution from the resins, for extracting 66 DBPs from water. Results demonstrate that among the 7 classes of DBPs investigated, trihalomethanes(ThMs), including iodo-ThMs, were the most efficiently adsorbed, with recovery of most ThMs ranging from 50%-96%, followed by halonitromethanes(40%-90%). The adsorption ability of XAD resins for haloacetonitriles, haloacetamides, and haloacetaldehydes was highly dependent on the individual species. The adsorption capacity of XAD resins for haloacetic acids was lower(5%-48%), even after adjusting to p h 1 before extraction. Recovery efficiency for most DBPs was comparable with their adsorption, as most were eluted effectively from XAD resins by ethyl acetate. DBP polarity and molecular weight were the two most important factors that determine their recovery. Recovery of trichloromethane, iodoacetic acid, chloro-and iodo-acetonitrile, and chloroacetamide were among the lowest, which could lead to underestimation of toxicity, particularly for iodoacetic acid and iodo-acetonitrile, which are highly toxic.

关键词： XAD resins Disinfection byproducts DBPs Recovery Toxicity

The impact of iodinated X-ray contrast agents on formation and toxicity of disinfection by-products in drinking water

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Journal of Environmental sciences 2017年第8期29卷 173-182页

作者： Clara h.Jeong Edward J.Machek Morteza shakeri stephen E.Duirk Thomas A.Ternes susan D.richardson Elizabeth D.Wagner Michael J.Plewa Molecular and Environmental Toxicology Center School of Medicine and Public Health University of Wisconsin-Madison Madison WI USA Department of Civil Engineering University of Akron Akron OH USA Department of Water Chemistry Federal Institute of Hydrology Koblenz Germany Department of Chemistry and Biochemistry University of South Carolina Columbia SC USA Department of Crop sciences and the safe Global Water Institute University of Illinois at Urbana-Champaign Urbana IL USA

The presence of iodinated X-ray contrast media（ICM） in source waters is of high concern to public health because of their potential to generate highly toxic disinfection by-products（DBPs）. The objective of this study was to determine the impact of ICM in source waters and the type of disinfectant on the overall toxicity of DBP mixtures and to determine which ICM and reaction conditions give rise to toxic by-products. source waters collected from Akron,Oh were treated with five different ICMs, including iopamidol, iopromide, iohexol,diatrizoate and iomeprol, with or without chlorine or chloramine disinfection. The reaction product mixtures were concentrated with XAD resins and the mammalian cell cytotoxicity and genotoxicity of the reaction mixture concentrates was measured. Water containing iopamidol generated an enhanced level of mammalian cell cytotoxicity and genotoxicity after disinfection. While chlorine disinfection with iopamidol resulted in the highest cytotoxicity overall, the relative iopamidol-mediated increase in toxicity was greater when chloramine was used as the disinfectant compared with chlorine. Four other ICMs（iopromide, iohexol, diatrizoate, and iomeprol） expressed some cytotoxicity over the control without any disinfection, and induced higher cytotoxicity when chlorinated. Only iohexol enhanced genotoxicity compared to the chlorinated source water.

关键词： Disinfection by-products Iodo-DBPs Iodinated X-ray contrast media

A multi-scale modelling framework to guide management of plant invasions in a transboundary context

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Forest Ecosystems 2016年第4期3卷 297-310页

作者： Joao Martins David M.richardson Renato henriques Elizabete Marchante hélia Marchante Paulo Alves Mirijam Gaertner Joao P.honrado Joana R.Vicente InBIO/CIBIO-Centro de Investigacao em Biodiversidade e Recursos Geneticos Universidade do Porto-Campus Agrario de VairaoRua Padre Armando Quintasn°74485-661 VairaoPortugal Centre for Invasion Biology Department of Botany and ZoologyStellenbosch UniversityMatieland 7602South Africa Institute of Earth sciences(ICT/University of Minho/CCT) MinhoPortugal Centre for Functional Ecology Department of Life SciencesUniversity of Coimbra3000-456 CoimbraPortugal Departamento de Ambiente Escola Superior Agraria de CoimbraInstituto Politecnico de CoimbraBencanta3045-601 CoimbraPortugal Faculdade de Ciencias da Universidade do Porto Ediffcio FC4(Biologia)Rua do Campo Alegres/n4169-007 PortoPortugal Environmental Resource Management Department Westlake Conservation OfficeOu Kaapse WegTokai7966 City of Cape TownSouth Africa

Background：Attention has recently been drawn to the issue of transboundary invasions,where species introduced and naturalized in one country cross international borders and become problematic in neighbouring *** modelling frameworks,able to identify the environmental drivers of invasion and forecast the current and future potential distribution of invasive species,are needed to study and manage *** due to the lack of species distribution and environmental data,or assumptions of modelling tools,often constrain the reliability of model ***：We present a multiscale spatial modelling framework for transboundary invasions,incorporating robust modelling frameworks（Multimodel Inference and Ensemble Modelling） to overcome some of the *** framework is illustrated using hakea sericea schrad.（Proteaceae）,a shrub or small tree native to Australia and invasive in several regions of the world,including the Iberian *** study scales were considered：regional scale（western Iberia,including mainland Portugal and Galicia） and local scale（northwest Portugal）.At the regional scale,the relative importance of environmental predictors sets was evaluated and ranked to determine the main general drivers for the species distribution,while the importance of each environmental predictor was assessed at the local *** potential distribution of *** was spatially projected for both scale ***：Model projections for western Iberia suggest that a large area is environmentally suitable in both Portugal and *** and landscape composition sets were the most important determinants of this regional distribution of the ***,a geological predictor（schist lithology） was more important in explaining its local-scale ***：After being introduced to Portugal,*** has become a transboundary invader by expanding in parts of Galicia（spain）.The fact that a larger area is predicted as

关键词： Drivers of invasion hakea sericea Multimodel inference Transboundary invasion management species distribution models

Impact of chlorine exposure time on disinfection byproduct formation in the presence of iopamidol and natural organic matter during chloramination

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Journal of Environmental sciences 2019年第4期31卷 204-214页

作者： Nana Osei B.Ackerson Alexis h.Killinger hannah K.Liberatore Thomas A.Ternes Michael J.Plewa susan D.richardson stephen E.Duirk Department of Civil Engineering University of Akron Department of Chemistry and Biochemistry University of South Carolina Federal Institute of hydrology (BfG) Department of Crop sciences and safe Global Water Institute and NsF science and Technology Center of Advanced Materials for the Purification of Water with systems University of Illinois at Urbana-Champaign

Chloramines,in practice,are formed onsite by adding ammonia to chlorinated drinking water to achieve the required *** regulated disinfection byproducts(DBPs)are reduced during chloramine disinfection,other DBPs such as iodinated(iodo-)DBPs,that elicit greater toxicity are *** objective of this study was to investigate the impact of prechlorination time on the formation of both halogen-specific total organic halogen(TOX)and iodo/chlorinated(chloro-)DBPs during prechlorination/chloramination in source waters(sWs)containing iopamidol,an X-ray contrast *** sW(BsW)and Cleveland sW(CsW)containing iopamidol were prechlorinated for 5–60 min and afterwards chloraminated for 72 hr with ammonium *** contact time(CCT)did not significantly impact total organic iodine(TOI)concentrations after prechlorination or *** of total organic chlorine(TOCl)formed during prechlorination did not significantly change regardless of ph and prechlorination time,whileTOClappearedtodecreaseafter 72 ***(ChCl_2I)formation during prechlorination did not exhibit any significant trends as a function of p h or CCT,but after chloramination,significant increases were observed at phs 6.5 and 7.5 with respect to ***-hAAs were not formed during prechlorination but were detected after *** quantities of chloroform(ChCl_3)and trichloroacetic acid(TCAA)were formed during prechlorination but formation ceased upon ammonia ***,prechlorination studies should measure TOX and DBP concentrations prior to ammonia addition to obtain data regarding the initial conditions.

关键词： Prechlorinaton Iopamidol Monochloramine Disinfection byproducts(DBPs) Total organic chlorine(TOCl) Total organic iodine(TOI)

Transition Metal Aluminum Boride as a New Candidate for Ambient-Condition Electrochemical Ammonia synthesis

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Nano-Micro Letters 2020年第5期12卷 106-118页

作者： Yang Fu Peter richardson Kangkang Li hai Yu Bing Yu scott Donne Erich Kisi Tianyi Ma Discipline of Chemistry School of Environmental and Life SciencesUniversity of NewcastleCallaghanNSW 2308Australia school of Engineering University of NewcastleCallaghanNSW 2308Australia CsIRO Energy 10 Murray Dwyer CircuitMayfield WestNSW 2304Australia school of Environmental science and Engineering Fujian Normal UniversityFuzhou 350007FujianPeople’s Republic of China

Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the haber-Bosch ***,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiencyhigh-energy consumption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RhE)].here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as MAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RhE)under ambient conditions and in alkaline *** to the unique nano-laminated crystal structure of the MAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(Nh3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic *** conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while Mo exhibits specific catalytic activity toward the subsequent reduction ***,the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR *** significance of this work is to provide a promising candidate in the future synthesis of ammonia.

关键词： MAB phase N2 reduction reaction Electrocatalysis Nanostructure

Biot反演在夏威夷钙质沉积物原位测量声速和衰减中的应用

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海洋学报 2005年第3期27卷 80-84页

作者：陶春辉 BAFFI s WILKENs R h FU s s richardson M D 金翔龙浙江大学地球科学系浙江杭州310014 夏威夷大学海洋与地球科技学院火奴鲁鲁96822 stennis空间中心海军研究实验室海洋地球科学部密执安州39529 国家海洋局海底科学重点实验室浙江杭州310012

对夏威夷檀香山岛的两个站(h3和h4)钙质沉积物进行了20～100khz的原位纵波声速和声衰减测量.它们均有轻微的频散.随频率的增加h3站位声速从1691m/s增加到1708m/s,h4站位的声速从1579m/s增加到1585m/s.随频率的增加h3站位的有效衰减从15d... 详细信息

对夏威夷檀香山岛的两个站(h3和h4)钙质沉积物进行了20～100khz的原位纵波声速和声衰减测量.它们均有轻微的频散.随频率的增加h3站位声速从1691m/s增加到1708m/s,h4站位的声速从1579m/s增加到1585m/s.随频率的增加h3站位的有效衰减从15dB/m增加到75dB/m,h4站位的有效衰减从22dB/m增加到62dB/m.运用Biot stoll模型对所测得的纵波速度和声衰减数据进行了Biot模型未知参数反演,发现粒径较大的h3站的沉积物(孔隙率为45%)比粒径较小的h4站的沉积物(孔隙率为56%)具有曲率小和渗透率及孔隙半径都大的性质.

关键词： Biot反演原位测试声速声衰减

Non-Assembly Walking Mechanism Utilizing a hexapod Gait

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Journal of Artificial Intelligence and Technology 2022年第4期2卷 158-163页

作者： George Jackson-Mills Andrew R.Barber Andrew Blight Andrew Pickering Jordan h.Boyle Bilal Kaddouh Robert C.richardson REAL Robotics Lab Institute of DesignRoboticsand Optimisation(iDRO)Mechanical EngineeringUniversity of LeedsLeeds LS29DYWest YorkshireUK Faculty of Industrial Design Engineering Delft University of TechnologyDelftNetherlands

small inspection robots allow for the optimal exploration of environments and the collection of data from challenging areas,particularly where there may be small access points or tight and fragile *** robots can be custom-built for specific tasks,but the design and assembly process for this can be costly,both in resources and assembly *** use of 3D printing to create Non-Assembly mechanisms can assist in saving time and resources by reducing the number of different components required and removing the necessity for complex assembly *** iterating on previous work performed in the institute,this paper introduces a novel robot design to push the capabilities of Non-Assembly *** building on previous knowledge,this new walking robot improves on the previous iteration by creating a more robust and reliable system,more capable of effectively exploring challenging environments accurately,while still using practices designed to save on cost and production *** tests were performed to provide an accurate comparison against the previous design and highlight the robots marked improvements in positional accuracy over its predecessor.

关键词： robot 3D printing walking hexapod

A balancing act: Optimizing free chlorine contact time to minimize iodo-DBPs, NDMA, and regulated DBPs in chloraminated drinking water

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Journal of Environmental sciences 2022年第7期34卷 315-325页

作者： Matthew A.Bloodgood sridevi Anduri Chowdary Eric J.Daiber honglan shi Caroline O.Granger susan D.richardson student services Authority U.S.Environmental Protection AgencyNational Exposure Research LaboratoryAthensGA 30605USA Department of Chemistry Missouri University of Science and TechnologyRollaMO 65409USA Department of Chemistry and Biochemistry University of South CarolinaColumbiaSC 29208USA

Many drinking water treatment plants in the U.s. have switched from chlorination to chloramination to lower levels of regulated trihalomethane(ThM) and haloacetic acid(hAA) disinfection byproducts(DBPs) in drinking water and meet the current regulations. however, chloramination can also produce other highly toxic/carcinogenic, unregulated DBPs: iodoacids, iodo-ThMs, and N-nitrosodimethylamine(NDMA). In practice, chloramines are generated by the addition of chlorine with ammonia, and plants use varying amounts of free chlorine contact time prior to ammonia addition to effectively kill pathogens and meet DBP regulations. however, iodo-DBPs and nitrosamines are generally not considered in this balancing of free chlorine contact time. The goal of our work was to determine whether an optimal free chlorine contact time could be established in which iodo-DBPs and NDMA could be minimized, while keeping regulated ThMs and hAAs below their regulatory limits. The effect of free chlorine contact time was evaluated for the formation of six iodo-trihalomethanes(iodo-ThMs), six iodo-acids, and NDMA during the chloramination of drinking water. Ten different free chlorine contact times were examined for two source waters with different dissolved organic carbon(DOC) and bromide/iodide. For the low DOC water at ph 7 and 8, an optimized free chlorine contact time of up to 1 h could control regulated ThMs and hAAs, as well as iodo-DBPs and NDMA. For the high DOC water, a free chlorine contact time of 5 min could control iodo-DBPs and NDMA at both p hs, but the regulated DBPs could exceed the regulations at ph 7.

关键词： Iodo-DBPs NDMA Disinfection byproducts Chloramine Drinking water Free chlorine contact time

培养全球观:日、加学生对于世界公民责任问题的看法

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比较教育研究 2002年第S1期23卷 237-243页

作者： George h.W.richardson David Blades 贾玉梅加拿大阿尔伯塔大学加拿大维多利亚大学教育部人文社会科学重点研究基地北京师范大学比较教育研究中心

这篇论文是一个关于加拿大和日本中学生(194人)怎样理解和想象“世界公民身份”的实验性研究的结果。对于研究结果的分析表明,尽管两国学生的看法有很多相似之处。但他们在形成全球观念的能力上存在重大差异——尤其是在多大程度上对未... 详细信息

这篇论文是一个关于加拿大和日本中学生(194人)怎样理解和想象“世界公民身份”的实验性研究的结果。对于研究结果的分析表明,尽管两国学生的看法有很多相似之处。但他们在形成全球观念的能力上存在重大差异——尤其是在多大程度上对未来持乐观态度和把自己看作解决全球问题的积极参与者方面。基于此,目前正在进行旨在强调国际化和跨文化对话的课程改革的日、加两国教育当局必须注意这些与培养学生世界公民观念密切相关的可能性与矛盾性。

关键词：世界公民责任可能性矛盾性跨学科国际合作