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1. New insights into particle transport in karst conduits using comparative tracer tests with natural sediments and solutes during low‐flow and high‐flow conditions

Author:
Dominik Richter; Nadine Goeppert; Nico Goldscheider
Source:
Hydrological processes 2022 v.36 no.1 pp. e14472
ISSN:
0885-6087
Subject:
tracer techniques,   etc   ; aquifers; dyes; hydrodynamics; karsts; models; solutes; streams; water management; Vietnam;     Show all 10 Subjects
Abstract:
... Colloidal particles are an important vector for the transport of contaminants in karst aquifers, characterized by a high degree of hydrologic variability. Understanding this heterogeneity and hydrogeological functioning is of particular importance for water management strategies. Until now, transport parameters for particles were mostly determined by injection of solutes or surrogates for natural ...
DOI:
10.1002/hyp.14472

2. Peroxone activated persulfate oxidation of 1,4-Dioxane under column scale conditions

Author:
M. Cashman; R. Ball; T. Lewis; T.B. Boving
Source:
Journal of contaminant hydrology 2022 v.245 pp. 103937
ISSN:
0169-7722
Subject:
tracer techniques,   etc   ; aquifers; dioxane; oxidants; oxidation; porous media; sand; slugs; water pollution;     Show all 9 Subjects
Abstract:
... The research presented herein investigates a peroxone activated persulfate (PAP) oxidant, commercialized under the trade name OxyZone®, and its effects on 1,4-Dioxane (dioxane) contaminated water under column scale conditions in the presence of porous material. There is a limited understanding of the underlying processes that govern PAP oxidation, including the oxidation rates in the presence of a ...
DOI:
10.1016/j.jconhyd.2021.103937

3. Performance evaluation of the Habanero enhanced geothermal system, Australia: Optimization based on tracer and induced micro-seismicity data

Author:
Tianfu Xu; Xu Liang; Yi Xia; Zhenjiao Jiang; Fabrizio Gherardi
Source:
Renewable energy 2022 v.181 pp. 1197-1208
ISSN:
0960-1481
Subject:
tracer techniques,   etc   ; diffusivity; electric power; permeability; porosity; renewable energy sources; sustainable development; Australia;     Show all 8 Subjects
Abstract:
... Understanding of hydraulic heterogeneity of the reservoir is the basis for Enhanced geothermal systems (EGS) optimization. This, however, is challenging, as there are limited well tests available for reservoir characterization. To overcome this challenge, this study developed a methodology for determining hydraulic parameters by integrating the induced micro-seismic data collected during the hydra ...
DOI:
10.1016/j.renene.2021.09.111

4. Water renewal estimation for sustainable aquaculture development in Ria de Aveiro and Rias Baixas

Author:
Leandro Vaz; Magda C. Sousa; Moncho Gómez-Gesteira; João M. Dias
Source:
Regional studies in marine science 2022 v.49 pp. 102098
ISSN:
2352-4855
Subject:
tracer techniques,   etc   ; aquaculture; estuaries; freshwater; geomorphology; hydrodynamics; marine science; models; oxygen; seasonal variation; summer; water quality; winter; Portugal; Spain;     Show all 15 Subjects
Abstract:
... Inshore aquaculture sustainability is extremely dependent on the efficiency of the water renewal at the culture sites, ensuring the supply of oxygen and nutrients to fish and/or bivalves. In this context, this study intends to investigate the effect of water quality on aquaculture development, assessing the water renewal rates in two contrasting coastal systems, Ria de Aveiro and Rias Baixas, unde ...
DOI:
10.1016/j.rsma.2021.102098

5. Tracer movements in a straight uniform flow: New equations for the advective part considering the distortion of flow lines around the well

Author:
Anthony Delbar; Robert P. Chapuis
Source:
Journal of contaminant hydrology 2021 v.239 pp. 103776
ISSN:
0169-7722
Subject:
tracer techniques,   etc   ; aquifers; groundwater; groundwater flow; isotropy;     Show all 5 Subjects
Abstract:
... Methods for interpreting tracer tests often rely on equations assuming a natural regional flow which is straight and uniform. The main purpose of this project was to develop more realistic equations for the advective part of contaminant transport, by including the flow lines distortion occurring in the vicinity of the injection well. The complex potential of the flow during a tracer test was calcu ...
DOI:
10.1016/j.jconhyd.2021.103776

6. Lattice distortion of CaF₂ nanocrystals for shortening their ¹⁹F longitude relaxation time

Author:
Ran Xu; Fanqiang Meng; Yanyue Liu; Dida Duosiken; Kang Sun; Sijian Pan; Ke Tao
Source:
Chemical communications 2021 v.57 no.72 pp. 9148-9151
ISSN:
1364-548X
Subject:
tracer techniques,   etc   ; chemical communication; image analysis; longitude; nanocrystals;     Show all 5 Subjects
Abstract:
... As a promising ¹⁹F MRI tracer, the relatively slow lattice-spin relaxation of CaF₂ nanocrystals leads to an unacceptable scanning time in MR imaging, hampering their application. We herein controlled the size and lattice distortion of CaF₂ nanocrystals and showed that the shortened interplanar spacing pronouncedly sped up the longitude relaxation. ...
DOI:
10.1039/d1cc02448e

7. Nucleophilic 18F-fluorination of phosphorofluoridates and phosphonofluoridic acids via imidazole-activated precursors

Author:
Zhaobiao Mou; Xueyuan Chen; Chao Wang; Tao Wang; Hongzhang Yang; Zijing Li
Source:
Tetrahedron letters 2021 v.68 pp. 152917
ISSN:
0040-4039
Subject:
tracer techniques,   etc   ; Lewis bases; acids; positron-emission tomography;     Show all 4 Subjects
Abstract:
... ¹⁸F-Labeled organofluorophosphates are important radiosynthons that have only been previously accessible via¹⁸/¹⁹F-isotope-exchange with limited molar activities. Herein, a novel ¹⁸F-fluorination methodology has been developed to prepare ¹⁸F-labeled phosphorofluoridates and phosphonofluoridic acids via the [¹⁸F]F⁻ nucleophilic substitution of imidazole-activated precursors. The efficient one-step ...
DOI:
10.1016/j.tetlet.2021.152917

8. Emulsion-Templated Macroporous Polymer Micromixers

Author:
Hande Barkan-Öztürk; Angelika Menner; Alexander Bismarck
Source:
Industrial & engineering chemistry process design and development 2021 v.60 no.39 pp. 14013-14025
ISSN:
1520-5045
Subject:
tracer techniques,   etc   ; laminar flow; polymers; porous media; process design;     Show all 5 Subjects
Abstract:
... Micromixers were fabricated from emulsion-templated macroporous polymers, known as polymerizing high internal-phase emulsions (polyHIPEs). Micromixers are mixing elements containing submillimeter channels, in which mixing occurs by molecular diffusion in the laminar flow regime. PolyHIPEs possess an interconnected pore structure with connected channels, which are ideal to mix liquids. We investiga ...
DOI:
10.1021/acs.iecr.1c01949

9. Tracer Dispersion through Karst Conduit: Assessment of Small-Scale Heterogeneity by Multi-Point Tracer Test and CFD Modeling

Author:
Romain Deleu; Sandra Soarez Frazao; Amaël Poulain; Gaëtan Rochez; Vincent Hallet
Source:
Hydrology 2021 v.8 no.4 pp. -
ISSN:
2306-5338
Subject:
tracer techniques,   etc   ; aquifers; geometry; hydrodynamics; karsts; rivers; spatial variation;     Show all 7 Subjects
Abstract:
... Tracer tests are widely used for characterizing hydrodynamics, from stream-scale to basin-wide scale. In karstic environments, the positioning of field fluorometers (or sampling) is mostly determined by the on-site configuration and setup difficulties. Most users are probably aware of the importance of this positioning for the relevance of data, and single-point tests are considered reliable. Howe ...
DOI:
10.3390/hydrology8040168

10. A Dye Tracer Approach for Quantifying Fluid and Solute Flux Across the Sediment–Water Interface

Author:
Ryan N. Cascarano; Donald M. Reeves; Mark A. Henry
Source:
Ground water 2021 v.59 no.3 pp. 428-437
ISSN:
0017-467X
Subject:
tracer techniques,   etc   ; equations; fluorescein; groundwater; models; sediment-water interface; solutes; stream channels;     Show all 8 Subjects
Abstract:
... We propose a dye tracer method to characterize fluid and solute fluxes across the sediment‐water interface. Zones of groundwater discharge within the streambed are first identified, and small volume slugs of 0.5 to 1 mL fluorescein dye are released at known subsurface depths. Fluorescein dye allows for visual identification of interface breakthrough locations and times, and dye concentrations at t ...
DOI:
10.1111/gwat.13060

11. Improving robustness and accuracy of predicted daily methane emissions of dairy cows using milk mid‐infrared spectra

Author:
Amélie Vanlierde; Frédéric Dehareng; Nicolas Gengler; Eric Froidmont; Sinead McParland; Michael Kreuzer; Matthew Bell; Peter Lund; Cécile Martin; Björn Kuhla; Hélène Soyeurt
Source:
Journal of the science of food and agriculture 2021 v.101 no.8 pp. 3394-3403
ISSN:
0022-5142
Subject:
tracer techniques,   etc   ; agriculture; data collection; lactation; methane; milk; milk yield; phenotype; prediction; regression analysis;     Show all 10 Subjects
Abstract:
... BACKGROUND: A robust proxy for estimating methane (CH₄) emissions of individual dairy cows would be valuable especially for selective breeding. This study aimed to improve the robustness and accuracy of prediction models that estimate daily CH₄ emissions from milk Fourier transform mid‐infrared (FT‐MIR) spectra by (i) increasing the reference dataset and (ii) adjusting for routinely recorded pheno ...
DOI:
10.1002/jsfa.10969

12. Turbulent mass transfer model for the simulation of liquid-solid CFB risers and its verification

Author:
Yawen Zhang; Panfeng Ren; Wenbin Li; Kuotsung Yu
Source:
Powder technology 2021 v.377 pp. 847-856
ISSN:
0032-5910
Subject:
tracer techniques,   etc   ; diffusion; diffusivity; mass; mass transfer; models; paper; solids; technology; turbulent flow; velocity;     Show all 11 Subjects
Abstract:
... Rigorous simulation of mass transfer process in liquid-solid circulating fluidized bed (LSCFB) system is challenging not only due to the fluidization but also due to the existing turbulence. In this paper, the recently developed c2¯−εc approach is introduced to characterize the turbulent mass diffusion in LSCFB riser so that the empirical turbulent mass diffusivity are abandoned. As for describing ...
DOI:
10.1016/j.powtec.2020.09.050

13. Using Quinine as a Fluorescent Tracer to Estimate Overland Flow Velocities on Bare Soil: Proof of Concept under Controlled Laboratory Conditions

Author:
João L. M. P. de Lima; Soheil Zehsaz; M. Isabel P. de Lima; Jorge M. G. P. Isidoro; Romeu Gerardo Jorge; Ricardo Martins
Source:
Agronomy 2021 v.11 no.7 pp. -
ISSN:
2073-4395
Subject:
tracer techniques,   etc   ; agronomy; dyes; fluorescence; overland flow; quantitative analysis; quinine; soil; surface water; ultraviolet radiation;     Show all 10 Subjects
Abstract:
... This study presents a tracer technique based on the fluorescent properties of quinine to help on the visualization of shallow flows and allow a quantitative measurement of overland flow velocities. Laboratory experiments were conducted to compare the traditional dye tracer and thermal tracer techniques with this novel fluorescent (quinine) tracer by injecting a quinine solution and the other trace ...
DOI:
10.3390/agronomy11071444

14. Roughness effect on the correction factor of surface velocity for rill flows

Author:
Alessio Nicosia; Costanza Di Stefano; Vincenzo Palmeri; Vincenzo Pampalone; Vito Ferro
Source:
Hydrological processes 2021 v.35 no.10 pp. e14407
ISSN:
0885-6087
Subject:
tracer techniques,   etc   ; Reynolds number; dyes; gravel; hydraulic flumes; hydrodynamics; overland flow; roughness; soil; travel; turbulent flow;     Show all 11 Subjects
Abstract:
... Flow velocity is one of the most important hydrodynamic variables for both channelized (rill and gullies) and interrill erosive phenomena. The dye tracer technique to measure surface flow velocity Vₛ is based on the measurement of the travel time of a tracer needed to cover a known distance. The measured Vₛ must be corrected to obtain the mean flow velocity V using a factor αᵥ = V/Vₛ which is gene ...
DOI:
10.1002/hyp.14407

15. Trace Organic Contaminant Transfer and Transformation in Bioretention Cells: A Field Tracer Test with Benzotriazole

Author:
Xinyao Gu; Timothy F. M. Rodgers; Sylvie Spraakman; Tim Van Seters; Robert Flick; Miriam L. Diamond; Jennifer Drake; Elodie Passeport
Source:
Environmental science & technology 2021 v.55 no.18 pp. 12281-12290
ISSN:
1520-5851
Subject:
tracer techniques,   etc   ; alanine; bioretention areas; chemical analysis; green infrastructure; soil; stormwater; technology; triazoles; urban runoff; water pollution;     Show all 11 Subjects
Abstract:
... Bioretention cells can effectively infiltrate stormwater runoff and partly remove conventional water contaminants. A field tracer injection experiment in a conventionally designed bioretention cell was used to investigate the fate of benzotriazole, a model trace organic contaminant, during and between runoff events. Moderate (29%) benzotriazole load reductions were measured during the 6 h long inj ...
DOI:
10.1021/acs.est.1c01062

16. Diffusion of perfluoroalkyl acids through clay-rich soil

Author:
Charles E. Schaefer; Dina Drennan; Anastasia Nickerson; Andrew Maizel; Christopher P. Higgins
Source:
Journal of contaminant hydrology 2021 v.241 pp. 103814
ISSN:
0169-7722
Subject:
tracer techniques,   etc   ; adsorption; diffusivity; hydrology; models; perfluorocarbons; perfluorooctane sulfonic acid; perfluorooctanoic acid; permeability; prediction; silty clay soils; sulfonates;     Show all 12 Subjects
Abstract:
... Diffusion through a water saturated silty clay soil column was measured for six perfluoroalkyl acids (PFAAs), including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). An aqueous pore diffusion model, which incorporated linear adsorption parameters measured independently in batch tests and a tortuosity factor determined independently using a bromide tracer test, was used to ...
DOI:
10.1016/j.jconhyd.2021.103814

17. One-year measurements of secondary organic aerosol (SOA) markers in the Paris region (France): Concentrations, gas/particle partitioning and SOA source apportionment

Author:
G.M. Lanzafame; D. Srivastava; O. Favez; B.A.M. Bandowe; P. Shahpoury; G. Lammel; N. Bonnaire; L.Y. Alleman; F. Couvidat; B. Bessagnet; A. Albinet
Source:
Science of the total environment 2021 v.757 pp. 143921
ISSN:
0048-9697
Subject:
tracer techniques,   etc   ; aerosols; air; biomass; combustion; environment; isoprene; nitrophenols; organic carbon; pollution; spring; summer; temperature; thermodynamic models; Asia; France;     Show all 16 Subjects
Abstract:
... Twenty-five biogenic and anthropogenic secondary organic aerosol (SOA) markers have been measured over a one-year period in both gaseous and PM₁₀ phases in the Paris region (France). Seasonal and chemical patterns were similar to those previously observed in Europe, but significantly different from the ones observed in America and Asia due to dissimilarities in source precursor emissions. Nitroaro ...
DOI:
10.1016/j.scitotenv.2020.143921

18. Measurement of Enteric Methane Emissions by the SF6 Technique Is Not Affected by Ambient Weather Conditions

Author:
Peter J. Moate; Jennie E. Pryce; Leah C. Marett; Josie B. Garner; Matthew H. Deighton; Brigid E. Ribaux; Murray C. Hannah; William J. Wales; S. Richard O. Williams
Source:
Animals 2021 v.11 no.2 pp. -
ISSN:
2076-2615
Subject:
tracer techniques,   etc   ; air temperature; automation; diet; dry matter intake; methane; methane production; rain; relative humidity; spring; sulfur hexafluoride; wind speed;     Show all 12 Subjects
Abstract:
... Despite the fact that the sulphur hexafluoride (SF₆) tracer technique was developed over 25 years ago to measure methane production from grazing and non-housed animals, no studies have specifically investigated whether ambient wind speed, temperature, relative humidity and rainfall influence the accuracy of the method. The aim of this research was to investigate how these weather factors influence ...
DOI:
10.3390/ani11020528

19. Investigation of hydraulic properties in fractured aquifers using cross-well travel-time based thermal tracer tomography: Numerical and field experiments

Author:
Quan Liu; Rui Hu; Linwei Hu; Yixuan Xing; Pengxiang Qiu; Huichen Yang; Steffen Fischer; Thomas Ptak
Source:
Journal of hydrology 2022 v.609 pp. 127751
ISSN:
0022-1694
Subject:
tracer techniques,   etc   ; heat transfer; models; solutes; tomography; Germany;     Show all 6 Subjects
Abstract:
... Hydraulic properties are well known to be essential in controlling fluid flow, solute migration, and heat transport in fractured subsurface. However, accurate characterization of hydraulic properties including the locations of conductive fracture and their hydraulic conductivities as well as their cross-well connectivity is still challenging. In this work, we modified the inversion framework of tr ...
DOI:
10.1016/j.jhydrol.2022.127751

20. A comparison of radon, heat tracer and head gradient methods to quantify surface water - groundwater exchange in a tidal wetland (Kooragang Island, Newcastle, Australia)

Author:
Mahmood Sadat-Noori; Christian Anibas; Martin S. Andersen; William Glamore
Source:
Journal of hydrology 2021 v.598 pp. 126281
ISSN:
0022-1694
Subject:
tracer techniques,   etc   ; carbon; ecological zones; ecosystems; equations; groundwater; head; heat transfer; models; nitrogen; radon; seawater; solutes; subsurface flow; surface water; wetlands; Australia;     Show all 17 Subjects
Abstract:
... Subsurface flow plays an important role in the functioning of wetlands and in the maintenance of their ecosystem services. Specifically, the transport and exchange of dissolved matter between sediments and surface waters is regulated by subsurface flow, which can strongly affect ecological zonation and productivity. Having a quantitative understanding of this subsurface flow is therefore important ...
DOI:
10.1016/j.jhydrol.2021.126281