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Nano-sized stationary phase packings retained by single-particle frit for microchip liquid chromatography

Chinese Chemical Letters 2024年第4期35卷 486-489页

作者： Wangyan Hu Ke Li Xiangnan Dou Ning Li Xiayan Wang Center Excellence for environmental Safety and Biological Effects Beijing Key Laboratory for Green Catalysis and SeparationDepartment of ChemistryBeijing University of TechnologyBeijing 100124China Center for environmental Metrology National Institute of MetrologyBeijing 100029China

Modern chromatography is increasingly focused on miniaturization and integration. Compared to conventional liquid chromatography, microfluidic chip liquid chromatography(microchip-LC) has the potential due to its zero-dead volume connection and ease of integration. Nano-sized packings have the potential to significantly enhance separation performance in microchip-LC. However, their application has been hindered by packing difficulties. This study presents a method for packing nano-sized silica particles into a microchannel as the stationary phase. The microchip-LC packed column was prepared by combining the weir and the porous silica single-particle as frit to retain the packing particles. A surface tensionbased single-particle picking technique was established to insert porous single-particle frit into glass microchannels. Additionally, we developed a slurry packing method that utilizes air pressure to inject nano-sized packing into the microchannel. Pressure-driven chromatographic separation was performed using this nano-packed column integrated into a glass microchip. The mixture of four PAHs was successfully separated within just 8 min using a 5 mm separation channel length, achieving high theoretical plates(10~6plates/m). Overall, these findings demonstrate the potential of utilizing nano-sized packings for enhancing chromatographic performance in microchip systems.

关键词： Nano-size packing Single-particle frit Packed column Microchip LC Chromatographic separation

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A typhoon-induced storm surge numerical model with GPU acceleration based on an unstructured spherical centroidal Voronoi tessellation grid

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Acta Oceanologica Sinica 2024年第3期43卷 40-47页

作者： Yuanyong Gao Fujiang Yu Cifu Fu Jianxi Dong Qiuxing Liu national Marine environmental Forecasting Center Beijing 100081China Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesBeijing 100081China

Storm surge is often the marine disaster that poses the greatest threat to life and property in coastal *** and timely issuance of storm surge warnings to take appropriate countermeasures is an important means to reduce storm surge-related *** surge numerical models are important for storm surge *** further improve the performance of the storm surge forecast models,we developed a numerical storm surge forecast model based on an unstructured spherical centroidal Voronoi tessellation(SCVT)*** model is based on shallow water equations in vector-invariant form,and is discretized by Arakawa C *** SCVT grid can not only better describe the coastline information but also avoid rigid transitions,and it has a better global consistency by generating high-resolution grids in the key areas through transition *** addition,the simulation speed of the model is accelerated by using the openACC-based GPU acceleration technology to meet the timeliness requirements of operational ensemble *** only takes 37 s to simulate a day in the coastal waters of *** newly developed storm surge model was applied to simulate typhoon-induced storm surges in the coastal waters of *** hindcast experiments on the selected representative typhoon-induced storm surge processes indicate that the model can reasonably simulate the distribution characteristics of storm *** simulated maximum storm surges and their occurrence times are consistent with the observed data at the representative tide gauge stations,and the mean absolute errors are 3.5 cm and 0.6 h respectively,showing high accuracy and application prospects.

关键词： typhoon-induced storm surge numerical model GPU acceleration unstructured grid spherical centroidal Voronoi tessellation(SCVT)

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Investigation of HO_(2) uptake mechanisms onto multiple-component ambient aerosols collected in summer and winter time in Yokohama,Japan

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Journal of environmental Sciences 2024年第3期137卷 18-29页

作者： Jun Zhou Yukiko Fukusaki Kentaro Murano Tania Gautam Yu Bai Yoshimi Inomata Hiroaki Komatsu Mayuko Takeda Bin Yuan Min Shao Yosuke Sakamoto Yoshizumi Kajii Institute for environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation forenvironmental Quality Guangzhou 511443China Graduate School of Global environmental Studies Kyoto UniversityKyoto606-8501Japan Yokohama environmental Science Research Institute Yokohama Kanagawa 221–0024Japan Department of Chemistry University of AlbertaAlbertaEdmonton T6G 2G2Canada Graduate School of Human and environmental Studies Kyoto UniversityKyoto 606-8501Japan Kanagawa environmental Research Center Kanagawa 254-0014Japan Center for Regional environmental Research National Institute for Environmental StudiesIbaraki305-8506Japan

The heterogeneous loss of HO_(2)radicals onto ambient aerosols plays an important role in tropospheric ***,sparse investigation of the dominating parameters controlling the HO_(2)uptake coefficients onto ambient aerosols(γHO_(2))has largely hindered the application of the measuredγHO_(2)to the global spatial *** we induced an offine method using LFP-LIF technique to measure the kinetics of HO_(2)uptake onto ambient aerosols collected in summertime and wintertime in Yokohama city,a regional urban site near Tokyo,*** controlling the dominating parameters which infuenceγHO_(2),we were able to investigate the detailed HO_(2)uptake *** characterized the chemical composition of the collected ambient aerosols,including organics,inorganics,transition metals ions,*** modeledγHO_(2)using different *** show thatγHO_(2)increased with the increase in RH,and the aerosol states(“dry”or wet/aqueous)have large effects onγHO_(2).With fixed RH and aerosol chemical composition,γHO_(2)was highly dependent on pH and inversely correlated with[HO_(2)]_*** combing the measuredγHO_(2)values with the modeled ones,we found that both the HO_(2)self-reaction and transition metal-catalyzed reactions should be accounted for to yield a single parameterization to predictγHO_(2),and different chemical compositions may have collective effects onγHO_(2).Results may serve for extending theγHO_(2)values measured at one observation site to different environmental conditions,which will help us to achieve more accurate modeling results concerning secondary pollutant formation(i.e.,ozone).

关键词： HO_(2)uptake kinetics Offine method Impacting factors Mechanism

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Tracking of horizontal alignment of the long and large diameter uncharged hole in NATM tunnel

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Underground Space 2024年第3期16卷 18-28页

作者： Min-Seong Kim Sean Seungwon Lee Department of Energy and Resources Engineering Chonnam National UniversityGwangju 61186Republic of Korea Department of Earth Resources and environmental Engineering Hanyang UniversitySeoul 04763Republic of Korea

The long and large diameter uncharged hole boring(LLB)method is a cut blasting method that minimizes blast-induced vibrations by creating long and large diameter uncharged holes at the excavation face of tunnels prior to tunnel *** in this method typically uses a 50 m long with a 382 mm diameter hammer bit in the horizontal direction at the tunnel ***,the significant weight and uni-directional rotation of the rod head,as well as variables such as geological characteristics,machine conditions,and inexperienced operators result in significant deviation from the target borehole alignment that hinders the vibration-dampening effect of the uncharged ***,since there is no method to verify the alignment of the boreholes until main tunnel construction,borehole misalignment is often not discovered until weeks after construction,which requires tunnel construction to cease until the equipment can be remobilized and an additional borehole be created,causing significant delays and increased costs for the entire tunnel *** this study,the borehole alignment tracking and ground exploration system(BGS)is developed to predict and monitor the quality and alignment of boreholes for cut blasting methods such as the LLB methods immediately after *** BGS was subsequently tested at a subway construction site to evaluate its performance in the *** measurements yielded by the BGS were compared with manually measured boring positions at every 5 m along the *** the BGS showed a maximum deviation of approximately 12%at a local point where the hole surface was relatively rough,the accuracy for the final boring position was approximately 97%,demonstrating excellent precision of the alignment tracking *** BGS demonstrates excellent performance in predicting ground conditions and the boring quality of a cut hole immediately after drilling,and shows promise in various other applications for monitoring borehole alignment.

关键词： Tunnel blasting LLB method Drilling deviation Vertical sagging Horizontal alignment tracking BGS

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Comprehensive insight into the occurrence characteristics,influencing factors and risk assessments of antibiotics in the Chaohu Basin

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Frontiers of environmental Science & Engineering 2024年第5期18卷 57-71页

作者： Shuanggang Hu Hongzhi Zhang Yongjie Yang Kangping Cui Junjie Ao Xuneng Tong Mengchen Shi Yi Wang Xing Chen Chenxuan Li Yihan Chen School of Resources and environmental Engineering Hefei University of TechnologyHefei230009China Ministry of Education-Shanghai Key Laboratory of Children’s environmental Health Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai200092China Department of Civil & environmental Engineering National University of SingaporeSingapore117576Singapore College of Resources and Environment Anhui Agricultural UniversityHefei230036China

The pollution of antibiotics in aquatic environments has received extensive ***,research on antibiotic contamination in river-lake systems,a significant form of modern aquatic environments,still needs to be *** study focuses on the Chaohu Basin(China)investigating the occurrence characteristics,influencing factors,and risk assessments of antibiotics in the river-lake *** total antibiotic concentrations in the water phase and sediment phase were 3.14–1887.49 ng/L and 0.92–1553.75 ng/g,*** was the predominant antibiotic in the water phase,whereas tetracycline prevailed in the sediment *** differences in concentration and structural composition of antibiotics between the tributaries(river system)and Chaohu Lake were observed,indicating the involvement of various geochemical processes in the attenuation of antibiotics during transport to the receiving *** analysis suggested that the western river is the primary source of antibiotics in Chaohu *** nutrient influx in heavily polluted areas is crucial to addressing the escalating issue of antibiotic pollution in the river-lake *** widespread occurrence of clindamycin in the waters is likely due to wastewater treatment plant discharges,and high-intensity human activities continue to exacerbate antibiotic *** assessment indicated that sulfamethoxazole,tetracycline,lincomycin,and clindamycin ranked in the top four with the highest risks to the most sensitive aquatic ***,the antibiotics presented no risk to consumer *** study provides valuable insights for controlling antibiotic pollution in riverlake systems.

关键词： Antibiotics Occurrence characteristics Influencing factors Risk assessments River-lake system

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Characteristics of Lightning Activity in Southeast China and its Relation to the Atmospheric Background

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Journal of Tropical Meteorology 2024年第1期30卷 76-88页

作者：支树林朱杰刘岩毛梦妮 Jiangxi Meteorological Observatory Nanchang 330096 China Key Laboratory of Radiometric Calibration and Validation for environmental satellites National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081 China Shanghai Typhoon Institute China Meteorological AdministrationShanghai 200030 China Innovation Center for FengYun Meteorological satellite(FYSIC) Beijing 100081 China Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210041 China Key Laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CICFEMD)Nanjing University of Information Science&TechnologyNanjing 210041 China Jiujiang Observatory JiujiangJiangxi 332000 China

Based on the lightning observation data from the Fengyun-4A(FY-4A)Lightning Mapping Imager(FY-4A/LMI)and the Lightning Imaging Sensor(LIS)on the International Space Station(ISS),we extract the“event”type data as the lightning detection *** observations are then compared with the cloud-to-ground(CG)lightning observation data from the China Meteorological *** study focuses on the characteristics of lightning activity in Southeast China,primarily in Jiangxi Province and its adjacent areas,from April to September,2017–*** addition,with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis data,we further delved into the potential factors influencing the distribution and variations in lightning activity and their primary related *** findings indicate that the lightning frequency and density of the FY-4A/LMI,ISS-LIS and CG data are higher in southern and central Jiangxi,central Fujian Province,and western and central Guangdong Province,while they tend to be lower in eastern Hunan *** general,the high-value areas of lightning density for the FY-4A/LMI are located in inland mountainous *** lower the latitude is,the higher the CG lightning density ***-value areas of the CG lightning density are more likely to be located in eastern Fujian and southeastern Zhejiang ***,the high-value areas of lightning density for the ISS-LIS are more dispersed,with a scattered distribution in inland mountainous areas and along the coast of eastern ***,the mountainous terrain is closely related to the high-value areas of the lightning *** locations of the high-value areas of the lightning density for the FY-4A/LMI correspond well with those for the CG observations,and the seasonal variations are also *** contrast,the distribution of the high-value areas of the lightning density for the ISS-LIS is more *** positions of the peak frequency of the FY-4A/LMI lightnin

关键词： lightning satellite and ground detections atmospheric background Southeast China

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Legacy and emerging per-and polyfluoroalkyl substances(PFAS) in the atmosphere: A comprehensive review

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Science China Technological Sciences 2024年第10期67卷 3032-3050页

作者： QIAO BiTing SONG DongBao CHEN Hao YAO YiMing SUN HongWen MOE Key Laboratory of Pollution Processes and environmental Criteria College of Environmental Science and EngineeringNankai University

With long-term production and widespread application, per-and polyfluoroalkyl substances(PFAS) have been detected in various media worldwide, including the atmosphere. Since the gradual restriction and phase-out of C8perfluoroalkyl acids(PFAAs), environmental contamination by emerging PFAS substitutes such as short-chain PFAA homologues, perfluoroether carboxylic, and sulfonic acids has been reported. Although there has been extensive monitoring of emerging PFAS substitutes in the aquatic environment, few studies have conducted target analysis and nontarget screening(NTS) of emerging unknown PFAS in the atmosphere over the past decade. To fill the gap, this review focused on emerging PFAS in the atmosphere in addition to legacy PFAS. The reported sampling, pretreatment, and instrumental analysis methods for target analysis and NTS of both neutral and ionic PFAS in the atmosphere are summarized, along with the advantages and current limitations of different sampling and NTS methods for PFAS in the atmosphere. The global levels, composition, and spatiotemporal distribution characteristics of legacy and emerging PFAS in the atmosphere are summarized and their transport, transformation, and dry/wet deposition are elucidated. The review highlights the importance of developing and applying the all-in-one strategy integrating target, suspect screening, and NTS to gain insights into emerging PFAS in the atmosphere and provide a reference for future research.

关键词： emerging PFAS atmosphere nontarget screening spatiotemporal distribution fate

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Inverse reliability analysis and design for tunnel face stability considering soil spatial variability

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1552-1564页

作者： Zheming Zhang Jian Ji Xiangfeng Guo Siang Huat Goh Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Department of Civil and environmental Engineering National University of SingaporeSingapore

The traditional deterministic analysis for tunnel face stability neglects the uncertainties of geotechnical parameters,while the simplified reliability analysis which models the potential uncertainties by means of random variables usually fails to account for soil spatial *** overcome these limitations,this study proposes an efficient framework for conducting reliability analysis and reliability-based design(RBD)of tunnel face stability in spatially variable soil *** three-dimensional(3D)rotational failure mechanism of the tunnel face is extended to account for the soil spatial variability,and a probabilistic framework is established by coupling the extended mechanism with the improved Hasofer-Lind-Rackwits-Fiessler recursive algorithm(iHLRF)as well as its inverse analysis *** proposed framework allows for rapid and precise reliability analysis and RBD of tunnel face *** demonstrate the feasibility and efficacy of the proposed framework,an illustrative case of tunnelling in frictional soils is presented,where the soil's cohesion and friction angle are modelled as two anisotropic cross-correlated lognormal random *** results show that the proposed method can accurately estimate the failure probability(or reliability index)regarding the tunnel face stability and can efficiently determine the required supporting pressure for a target reliability index with soil spatial variability being taken into ***,this study reveals the impact of various factors on the support pressure,including coefficient of variation,cross-correlation between cohesion and friction angle,as well as autocorrelation distance of spatially variable soil *** results also demonstrate the feasibility of using the forward and/or inverse first-order reliability method(FORM)in high-dimensional stochastic *** is hoped that this study may provide a practical and reliable framework for determining the stability of tunnels in complex

关键词： Limit analysis Tunnel face stability Spatial variability HLRF algorithm Inverse reliability method

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Evolution hydrothermal aging resistance mechanism study of zirconium and manganese doped CeO_(2)catalysts in soot catalytic combustion based on low Miller indices crystal surface effect

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Journal of Rare Earths 2024年第7期42卷 1272-1281,I0003页

作者： Zonglin Li Pan Wang Hong Ni Chengcheng Ao Lidong Zhang Hefeng Zhang Kai Li School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China State environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental ScienceBeijing100012China national Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230026China

The thermogravimetric analysis(TGA)experiments were carried out to reveal the mechanism of Zr and Mn doping on catalytic activity of CeO_(2)catalyst both fresh and after hydrothermal aging,and the lattice morphology and valence changes were characterized by means of Brunauer-Emmett-Teller(BET)method,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and H_(2)-temperature programmed reduction(H_(2)-TPR).Density functional theory(DFT)and molecular thermodynamics calculations were applied to investigate the change in catalytic activity,crystal surface energy and crystal morphology caused by hydrothermal *** maximum reaction rate temperature of fresh Mn/CeO_(2)(389℃)is similar to that of CeO_(2)(371℃)and lower than that of Zr/CeO_(2)(447℃),but the catalytic performance of CeO_(2)decreases more severely after hydrothermal *** catalyst crystals show different degrees of crystal surface migration after hydrothermal aging,which leads to the reduction of Ce^(3+)/Ce^(4+) ratio and the active sites *** calculations indicate that the doping of Zr and Mn reduces the surface energy of the low Miller indices surface and increases the oxygen vacancy formation energy,leading to better thermal stability and lower catalytic *** Zr and Mn doping also changes the adsorption energy and Gibbs free energy of H_(2)O,which dominates the migration of(111)to(110)and(100)in the vapor *** crystal surface migration mechanism of CeO_(2)catalysts doped with Zr and Mn induced by H_(2)O molecules at high temperature obtained in this study can provide a valuable addition to the regeneration of CeO_(2)catalysts in the after-treatment systems of diesel engines.

关键词： Soot CeO_(2)-based catalyst CDPF Rare earth metal oxides DFT calculations

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Water temperature governs organophosphate ester dynamics in the aquatic food chain of Poyang Lake

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environmental Science and Ecotechnology 2024年第5期21卷 197-207页

作者： Zhenfei Yan Chenglian Feng Yiping Xu Jindong Wang Nannan Huang Xiaowei Jin Fengchang Wu Yingchen Bai State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China College of Environment Hohai UniversityNanjing210098China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China China national environmental Monitoring Centre Beijing100012China

Organophosphate esters(OPEs)are increasingly recognized as pervasive environmental contaminants,primarily from their extensive application in flame retardants and *** their widespread presence,the intricacies of OPE bioaccumulation within aquatic ecosystems remain poorly understood,particularly the environmental determinants influencing their distribution and the bioaccumulation dynamics across aquatic food *** we show that water temperature plays a crucial role in modulating the dispersion of OPE in the aquatic environment of Poyang *** quantified OPE concentrations across various matrices,uncovering levels ranging from 0.198 to 912.622 ng L^(-1) in water,0.013e493.36 ng per g dry weight(dw)in sediment,0.026e41.92 ng per g wet weight(ww)in plankton,0.13e2100.72 ng per g dw in benthic invertebrates,and 0.31e3956.49 ng per g dw in wild fish,highlighting a pronounced bioaccumulation ***,the intestines emerged as the principal site for OPE absorption,displaying the highest concentrations among the seven tissues *** the various OPEs,tris(chloroethyl)phosphate was distinguished by its significant bioaccumulation potential within the aquatic food web,suggesting a need for heightened *** propensity for OPE accumulation was markedly higher in benthic invertebrates than wild fish,indicating a differential vulnerability within aquatic *** study lays a foundational basis for the risk assessment of OPEs as emerging contaminants and underscores the imperative to prioritize the examination of bioaccumulation effects,particularly in benthic invertebrates,to inform future environmental safeguarding strategies.

关键词： Organophosphate esters Driving factor Bioaccumulation and biomagnification Ecological risk

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