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Dissolved barium as a tracer of Kuroshio incursion in the Kuroshio region east of Taiwan Island and the adjacent East China Sea

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Science China Earth Sciences 2017年第7期60卷 1356-1367页

作者： LIU Wei SONG JinMing YUAN HuaMao LI Ning LI XueGang DUAN LiQin Chinese Academy of Sciences Key Laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China University of Chinese Academy of Sciences Beijing 100049 China Shandong Analysis and Test Center Jinan 250014 China Laboratory for Marine Ecology and Environmental Sciences Qingdao National Laboratory for Marine science and Technology Qingdao 266237 China

From May to June 2014, the geochemical characteristics of dissolved barium(Ba) in sea water and its influx from the Kuroshio into the East China Sea(ECS) were studied by investigation of the Kuroshio mainstream east of Taiwan Island and the adjacent ECS. This allowed for the scope and extent of the Kuroshio incursion to be quantitatively described for the first time by using Ba as a tracer. The concentration of Ba in the Kuroshio mainstream increased gradually downward from the surface in the range 4.91–19.2 μg L.1. In the surface layer of the ECS, the Ba concentration was highest in coastal water and gradually decreased seaward, while it was higher in coastal and offshore water but lowest in middle shelf for bottom layer. The influx of Ba from Kuroshio into the ECS during May to October was calculated to be 2.19×108 kg by a water exchange model, in which the subsurface layer had the largest portion. The distribution of Ba indicated that Kuroshio upwelled in the sea area northeast of Taiwan Island. The north-flowing water in the Taiwan Strait restrained the incursion of Kuroshio surface water onto the ECS shelf, while Kuroshio subsurface water gradually affected the bottom of the ECS from outside. The results of end member calculation, using Ba as a parameter, showed that the Kuroshio surface water had little impact on the ECS, while the Kuroshio subsurface water formed an intrusion current by climbing northwest along the bottom of the middle shelf from the sea area northeast of Taiwan Island into the Qiantang Estuary, of which the volume of Kuroshio water was nearly 65%. Kuroshio water was the predominant part of the water on the outer shelf bottom and its proportion in areas deeper than the 100 m isobath could reach more than 95%. In the DH9 section(north of Taiwan Island), Kuroshio subsurface water intruded westward along the bottom from the shelf edge and then rose upward(in lower proportion). Kuroshio water accounted for 95% of the ocean volume could reach as f

关键词： Dissolved barium tracer Geochemical characteristics Kuroshio incursion The ECS shelf

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Self-adaptive behavior of nunchakus-like tracer induced by active Brownian particles

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Chinese Physics B 2022年第4期31卷 90-95页

作者： Yi-Qi Xia Guo-Qiang Feng Zhuang-Lin Shen Department of Physics and Electronic Engineering Yancheng Teachers UniversityYancheng 224007China Center for Soft Condensed Matter Physics&Interdisciplinary Research School of Physical Science and TechnologySoochow UniversitySuzhou 215006China Department of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

We design a nunchakus-like tracer and investigate its self-adaptive behavior in an active Brownian particle(ABP)bath via systematically tuning the self-propelled capability and density of ***,the nunchakus-like tracer will have a stable wedge-like shape in the ABP bath when the self-propelled force is high *** analyze the angle between the two arms of the tracer and the velocity of the joint point of the *** angle exhibits a non-monotonic phenomenon as a function of active ***,it increases with density of ABPs increasing monotonically.A simple linear relationship between the velocity and the self-propelled force is found under the highly active *** other words,the joint points of the tracer diffuse and the super-diffusive behavior can make the relation between the self-propelled force and the density of ABPs persist *** addition,we find that the tracer can flip at high density of *** results also suggest the new self-adaptive model research of the transport properties in a non-equilibrium medium.

关键词： tracer self-adaptive super-diffusion active Brownian particles

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Comparison of smoothness-constrained and geostatistically based cross-borehole electrical resistivity tomography for characterization of solute tracer plumes

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Water Science and Engineering 2016年第4期9卷 274-286页

作者： Andreas Englert Andreas Kemna Jun-feng Zhu Jan Vanderborght Harry Vereecken Tian-Chyi J.Yeh Institute of Geology Mineralogy and GeophysicsRuhr University Bochum Department of Geophysics Steinmann InstituteUniversity of Bonn Kentucky Geological Survey University of Kentucky Agrosphere Institute for Bio- and Geosciences(IBG-3)Forschungszentrum Jlich GmbH Department of Resources Engineering National Cheng Kung University Department of Hydrology and Water Resources The University of Arizona

Experiments using electrical resistivity tomography(ERT) have shown promising results in reducing the uncertainty of solute plume characteristics related to estimates based on the analysis of local point measurements *** explore the similarities and differences between two cross-borehole ERT inversion approaches for characterizing salt tracer plumes,namely the classical smoothness-constrained inversion and a geostatistically based approach,we performed two-dimensional synthetic *** assumptions about the solute transport model and the electrical forward and inverse model allowed us to study the sensitivity of the ERT inversion approaches towards a variety of basic conditions,including the number of boreholes,measurement schemes,contrast between the plume and background electrical conductivity,use of a priori knowledge,and point *** results show that geostatistically based and smoothness-constrained inversions of electrical resistance data yield plume characteristics of similar quality,which can be further improved when point measurements are incorporated and advantageous measurement schemes are *** expected,an increased number of boreholes included in the ERT measurement layout can highly improve the quality of inferred plume characteristics,while in this case the benefits of point conditioning and advantageous measurement schemes *** ERT inversion approaches are similarly sensitive to the noise level of the data and the contrast between the solute plume and background electrical conductivity,and robust with regard to biased input parameters,such as mean concentration,variance,and correlation length of the *** sophisticated inversion schemes have recently become available,in which flow and transport as well as electrical forward models are coupled,these schemes effectively rely on a relatively simple geometrical parameterization of the hydrogeological ***,we believe that standard uncoupled ER

关键词： Electrical resistivity tomography Inversion technique Solute tracer plume Synthetic experiment Plume characteristics

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tracer Experimental Study of the Main Conveying Conduits of CCl_4 Pollutant in the Qiligou Water Supply Resource

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Journal of China University of Mining and Technology 2007年第2期17卷 184-187页

作者： PEI Zong-ping HAN Bao-ping LIU Han-hu LIANG Zhi ZHOU Dong-lai ZHU Xue-qiang School of Environment and Spatial Informatics China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The Ordovician karst groundwater in the Qiligou basin is an important water supply source. This groundwater has been seriously contaminated in recent years by Cfl4 from a pesticide plant located in the recharge area. The highest concentration of CCl4 in the groundwater is 3909.2μg/L. Large scale tracer experiments were carried out to study the conveying conduits for Cfl4 in the basin on May 1-6, 2005. Nontoxic, edible glucose was used as a tracer and it was detected by spectrophotometric techniques. Well area of the basin, was employed for injecting the tracer X-61, located near the pesticide plant in the southern recharge Ten wells widely located in the groundwater runoff area were used as observing and sampling wells. The results show that the migration of the pollutants is controlled by the water hydrodynamic field and by the development of karst conduits. The tracer did not enter the up-drainage wells, X-49 and X-47, near the injection point because the water levels at these wells are higher than at the injection point. The adjacent well X-62 is close to the injection site, but the tracer reached the well after eleven hours. Wells X-43, X-59, X-58, YY-1 and X-57, located in the syncline axis runoff area, are respectively 2.5, 3.5, 4.33, 4.38 and 5.44 kilometers from the in- jection site. The time for initial appearance of tracer was 4, 4, 2, 6 and 4 hours, respectively. The maximum runoff velocity （well X-58） is over two kilometers per hour, indicating that the karst conduits are well developed along the syncline basin axis. These conduits are the main conveying conduits for groundwater and Cfl4. Closer wells were not necessarily the first to receive tracer. This shows the inhomogeneity in karst development which causes complex runoff, and pollutant migration, patterns.

关键词： tracer experiment tracer karst groundwater CC14 contamination conveying conduit

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A new anterograde trans-synaptic tracer based on Sindbis virus

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Neural Regeneration Research 2022年第12期17卷 2761-2764页

作者： Xiang-Wei Shi Fan Jia Pei Lyu Fu-Qiang Xu State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Key Laboratory of Magnetic Resonance in Biological SystemsWuhan Center for Magnetic ResonanceInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhanHubei ProvinceChina Guangdong Provincial Key Laboratory of Brain Connectome and Behavior CAS Key Laboratory of Brain Connectome and Manipulationthe Brain Cognition and Brain Disease Institute(BCBDI)Translational Research Center for the Nervous System(TRCNS)Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhenGuangdong ProvinceChina NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products Key Laboratory of Quality Control Technology for Virus-Based TherapeuticsGuangdong Provincial Medical Products AdministrationShenzhen Key Laboratory of Viral Vectors for BiomedicineShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina University of Chinese Academy of Sciences BeijingChina Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhanHubei ProvinceChina

Mapping neural circuits is critical for understanding the structure and function of the nervous *** viruses are a valuable tool for tracing neural ***,current tracers do not fully meet the needs for this approach because of various drawbacks,such as toxicity and characteristics that are difficult to ***,there is an urgent need to develop a new tracer with low toxicity and that allows for long-term *** this study,we constructed an engineered Sindbis virus(SINV)expressing enhanced green fluorescent protein(EGFP)reporter gene(SINV-EGFP)and found that it had no significant difference in biological characterization compared with the wild-type Sindbis virus in BHK-21 cells and neurons in *** injected the virus into the visual circuit of mouse brain and found that the virus infected neurons in the local injected site and anterogradely spread in the neural *** the efficiency of transmission was limited,the findings demonstrate that SINV can be used as a new anterograde tracer to map neural circuits in mouse brain and that it spreads exclusively in the anterograde ***,use of SINV in mouse brain research will provide longer time windows for circuit tracing than is possible with herpes simplex virus and vesicular stomatitis virus tracers.

关键词： anterograde lateral geniculate nucleus mouse brains neural circuit neurons retina Sindbis virus superior colliculus synapse tracer

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Performance evaluation of a water erosion tracer using plot-scale experiments and process-based modeling

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International Soil and Water Conservation Research 2023年第4期11卷 622-632页

作者： João M.Villela Jamil A.A.Anache Alex M.Watanabe Dennis C.Flanagan Edson C.Wendland Silvio Crestana EMBRAPA-Brazilian Agricultural Research Corporation LNNA-National Laboratory of Nanotechnology for AgrobusinessSt.XV de NovembroSão CarlosSP13560-970Brazil University of São Paulo(USP) São Carlos School of Engineering.Graduate Program in Environmental Engineering Sciences(PPG-SEA)Av.Trabalhador São-CarlenseCxP.359São CarlosSP13566590Brazil Department of Hydraulics and Sanitation São Carlos School of Engineering(EESC)University of São Paulo(USP)CxP.359São CarlosSP13566-590Brazil Federal University of Mato Grosso Do Sul CxP.549Campo Grande.MS.79070-900Brazil USDA-Agricultural Research Service National Soil Erosion Research Laboratory275 S.Russell StWest LafayetteIN47907USA

Socioeconomic and environmental losses caused by water erosion have highlighted the importance of quantifying and understanding the dynamics of soil redistribution in the landscape to develop effective soil management *** methods are applied to estimate erosion/deposition rates and identify sources of sediments,among them,the one that uses rare earth elements(REE)as a tracer stands ***,an alternative not yet explored that can benefit the accuracy of the estimates provided by the method is using a tracer containing a chemical signature composed of more than one *** present study aimed to evaluate the performance of a new water erosion tracer based on montmoril-lonite labeled with rare earth elements(La40-MMT).The innovative aspects of this La40-MMT tracer include its highly stable multi-chemical signature(Nd^(3+),La^(3+),and Pr^(3+)),which enhances tracer detection in the environment,and its low production cost due to the use of an industrial residue in the synthesis *** tracer was evaluated for a typical soil of the Cerrado biome,using a natural rainfall field-scale plot-NRFP(5 m × 20 m)and a physical predictive erosion model(WEPP).The results showed that the La40-MMT tracer could be used to estimate erosion/deposition rates,with agreement between the values observed with the tracer and the WEPP ***,this study confirmed the great potential of La40-MMT as a tool to identify patterns of soil redistribution at the field scale and aid in the validation of erosion models.

关键词： Soil erosion tracer Rare earth elements Deposition Sediment source WEPP Model

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Biotinylated dextran amine is an ideal anterograde tracer for the corticospinal tract in a goat model of ischemic corticospinal tract injury

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Neural Regeneration Research 2011年第25期6卷 1960-1964页

作者： Xiaoyu Yang Yufei Gao Zhigang Qin Xia Cao Xinquan Gu China-Japan Union Hospital Jifin University Changchun 130033 Jilin Province China School of Pharmaceutical Sciences Jilin University Changchun 130021 Jifin Province China

Existing visualized tracer studies of the corticospinal tract have been focused on rodents, which have markedly different spinal cord structures compared with humans. In this study, the segmental artery feeding the spinal cord was embolized with digital subtraction angiography to establish a goat model of ischemic spinal cord injury. Biotinylated dextran amine was injected into the motor function areas of the cortex in goats with ischemic spinal cord injury. The corticospinal tract originates from the cerebral cortex motor function area, and travels towards the lateral funiculus at the contralateral spinal dorsal horn after decussation at the pyramid. The number of corticospinal tract positive fibers was found to be gradually reduced. These findings indicate that digital subtraction angiography can be applied to a goat model of ischemic spinal cord injury. Biotinylated dextran amine visualizes the course of the goat corticospinal tract in the spinal cord, which is similar to the human spinal cord. Biotinylated dextran amine is an ideal tracer for the corticospinal tract.

关键词： corticospinal tract biotinylated dextran amine ischemic spinal cord injury digital subtraction angiography tracer neuroanatomy neural regeneration

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Study of fissured-rock seepage flow with isotope tracer method in single borehole

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Science China(Technological Sciences) 2001年第S1期44卷 108-113页

作者：陈建生董海洲 Institute of Geotechnical Engineering Hohai University Nanjing China

A systematic summary is presented describing the application of isotope tracer method in detecting seepage flow in a single borehole. In a single borehole, many hydraulic coefficients, such as flow velocity, direction of flow, vertical flow etc., can be obtained by using isotope tracer method. There are three conditions if a fissure intersects a borehole: vertical, parallel and tilt. According to each different condition, the formulation of flow velocity deduced by isotope dilution method is different. At the same time, well theory of blended borehole about fissure groups including single fissure group and multi-fissure groups, has also been discussed.

关键词： isotope tracer method fissured rock seepage flow.

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A theoretical framework of tracer methods for marine sediment dynamics

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Chinese Science Bulletin 2000年第15期45卷 1434-1440页

作者： GAO ShuInstitute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China Institute of Oceanology Chinese Academy of Sciences Qingdao China

A new theoretical framework of tracer methods is proposed in the present contribution, on the basis of mass conservation. This model is applicable for both artificial and natural tracers. It can be used to calculate the spatial distribution patterns of sediment transport rate, thus providing independent information and verification for the results derived from empirical formulae. For the procedures of the calculation, first, the tracer concentration and topographic maps of two times are obtained. Then, the spatial and temporal changes in the concentration and seabed elevation are calculated, and the boundary conditions required are determined by field observations (such as flow and bedform migration measurements). Finally, based upon eqs. (1) and (13), the transport rate is calculated and expressed as a function of the position over the study area. Further, appropriate modifications to the model may allow the tracer to have different densities and grain size distributions from the bulk sediment.

关键词： sediment transport tracer methods marine environment modeling.

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A Study of Neutron Activation tracer Sediment Technique

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Science China Mathematics 1993年第2期36卷 243-247页

作者：尹毅常乃环仲维妮孙树正张蕴辉崔海平陈声亮冯玉林孙连成 First Institute of Oceanography SOA Qingdao 266003 PRC Institute of Atomic Energy Beijing 102413 PRC Tianjin Institute of Water Transport Engineering Ministry of Communications Tianjin 300456 PRC

In this study, iridium (Ir) was selected as a signal element, the chemical adsorption tagging method was adopted to make the tracer sediments, the neutron activation analysis method was used to determine the signal element content in sediments, and the sediment transport law was judged according to the movement characteristics of the signal elements. This method overcomes the shortcomings of the fluorescent sediment technique and radioactive tracer sediment technique. It is capable of simulating truly the movement characteristics of natural sediments. Therefore, it is an advanced technique for observation of the sediment movement. The expectant effects were obtained in the experiment on the first domestic practical application of this method carried out in Tianjin Port.

关键词： tracer element radioactive tracer neutron activation analysis isotope.

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