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1. Assessment of Lagrangian particle dispersion model “LAPMOD” through short range field tracer test in complex terrain

Author:
Haq, Amin ul; Nadeem, Qaisar; Farooq, Amjad; Irfan, Naseem; Ahmad, Masroor; Ali, Muhammad Rizwan
Source:
Journal of environmental radioactivity 2019 v.205-206 pp. 34-41
ISSN:
0265-931X
Subject:
tracer techniques,   etc   ; landscapes; models; radioactivity; receptors;     Show all 5 Subjects
Abstract:
... In this paper the mesoscale application of the 3D Lagrangian particle dispersion model LAPMOD has been assessed for a field tracer test performed in a short-range complex terrain. The meteorological input was provided through the diagnostic model CALMET, the meteorological pre-processor of the CALPUFF model. The CALMET/LAPMOD coupled system was used to simulate the hourly averaged ground level con ...
DOI:
10.1016/j.jenvrad.2019.04.015

2. Dispersion of Tracers in the Stable Atmosphere of a Valley Opening onto a Plain

Author:
Quimbayo-Duarte, Julian; Staquet, Chantal; Chemel, Charles; Arduini, Gabriele
Source:
Boundary-layer meteorology 2019 v.172 no.2 pp. 291-315
ISSN:
0006-8314
Subject:
tracer techniques,   etc   ; gravity; theoretical models; urbanization;     Show all 4 Subjects
Abstract:
... We quantify the impact of a valley-wind system on the transport of passive tracers in the stably-stratified atmosphere of a valley dynamically decoupled from the atmosphere above. The simple configuration of an idealized Alpine-type valley opening onto a plain is considered, for two values of the initial buoyancy frequency and of the valley steepness. The valley-wind system consists of thermally-d ...
DOI:
10.1007/s10546-019-00439-2

3. Simulation and theory of open-tube dispersion in short and long capillaries with slip boundaries and retention

Author:
Beauchamp, Matthew D.; Schure, Mark R.
Source:
Journal of chromatography 2019 v.1588 pp. 85-98
ISSN:
0021-9673
Subject:
tracer techniques,   etc   ; chromatography; liquids; separation; solutes;     Show all 5 Subjects
Abstract:
... Using random walk techniques, high resolution simulations of zone shape are conducted in open capillary tubes for short and long tube conditions. Finite size solutes are used as tracers in this treatment. Slip flow boundary conditions and wall retention are utilized as needed. These simulations are able to reproduce previous work in short and long tubes. For the short tube case where dispersion do ...
DOI:
10.1016/j.chroma.2018.12.040

4. Cation Diffusion in Compacted Clay: A Pore-Scale View

Author:
Yang, Yuankai; Wang, Moran
Source:
Environmental science & technology 2019 v.53 no.4 pp. 1976-1984
ISSN:
1520-5851
Subject:
tracer techniques,   etc   ; cations; clay; topology; waste disposal;     Show all 5 Subjects
Abstract:
... Cation diffusion through compacted clays is of great interest due to its potential for buffer materials for waste disposal. The importance of the electrokinetic effect on cationic tracer diffusion is investigated by using pore-scale simulations to consider the influence from the electrokinetic properties and topology of clays. It is indicated that the normalized volume charge density has a signifi ...
DOI:
10.1021/acs.est.8b05755

5. Ring-Closing Synthesis of Dibenzothiophene Sulfonium Salts and Their Use as Leaving Groups for Aromatic 18F-Fluorination

Author:
Gendron, Thibault; Sander, Kerstin; Cybulska, Klaudia; Benhamou, Laure; Sin, Pak Kwan Brian; Khan, Aqsa; Wood, Michael; Porter, Michael J.; Årstad, Erik
Source:
Journal of the American Chemical Society 2018 v.140 no.35 pp. 11125-11132
ISSN:
1520-5126
Subject:
tracer techniques,   etc   ; fluorides; regioselectivity;     Show all 3 Subjects
Abstract:
... Herein, we report a novel intramolecular ring-closing reaction of biaryl thioethers that give access to highly functionalized dibenzothiophene sulfonium salts under mild conditions. The resulting precursors react regioselectively with [¹⁸F]fluoride to give [¹⁸F]fluoroarenes in predictable radiochemical yields. The strategy expands the available radiochemical space and provides superior labeling ef ...
DOI:
10.1021/jacs.8b06730

6. Analysis of radially convergent tracer test in a two-zone confined aquifer with vertical dispersion effect: Asymmetrical and symmetrical transports

Author:
Huang, Ching-Sheng; Tong, Chenchen; Hu, Wei-Shan; Yeh, Hund-Der; Yang, Tao
Source:
Journal of hazardous materials 2019 v.377 pp. 8-16
ISSN:
0304-3894
Subject:
tracer techniques,   etc   ; confined aquifer; finite element analysis; models; prediction;     Show all 5 Subjects
Abstract:
... Radially convergent tracer test (RCT) with an extraction well and a tracer injection well is commonly conducted for determining aquifer dispersivity associated with the spreading of contamination plume. A variety of analytical models for RCT have been proposed, but the effects of skin zone and vertical dispersion are rarely explored. In addition, little attention is paid to the validity of those a ...
DOI:
10.1016/j.jhazmat.2019.05.042

7. Comparative study of nanofiltration membrane characterization devices of different dimension and configuration (cross flow and dead end)

Author:
Imbrogno, Alessandra; Schäfer, Andrea I.
Source:
Journal of membrane science 2019 v.585 pp. 67-80
ISSN:
0376-7388
Subject:
tracer techniques,   etc   ; artificial membranes; hydrodynamics; mass transfer; nanofiltration; systems engineering;     Show all 6 Subjects
Abstract:
... Comparison of nanofiltration characterization data from literature is challenging due to different hydrodynamics and system designs, which affect membrane retention. In this study, stirred cell (SC), micro and macro cross flow systems (micro and macro CF) with different configuration were used to measure salt and organic tracer retention. Minimal concentration polarization conditions were applied ...
DOI:
10.1016/j.memsci.2019.04.035

8. Correction to: Monte Carlo fingerprinting of the terrestrial sources of different particle size fractions of coastal sediment deposits using geochemical tracers: some lessons for the user community

Author:
Gholami, Hamid; Jafari Takhti Najad, Ebrahim; Collins, Adrian L.; Fathabadi, Aboalhasan
Source:
Environmental science and pollution research international 2019 v.26 no.22 pp. 23206
ISSN:
0944-1344
Subject:
tracer techniques,   etc   ; coastal sediments; particle size; sediment deposition;     Show all 4 Subjects
Abstract:
... The original publication of this paper contains a mistake. The correct University name of the 3rd affiliation is shown in this paper. ...
DOI:
10.1007/s11356-019-05443-0

9. Recent multi-tracer dating of the Black Sea sediments: Recovery of the late post-Chernobyl trends of radioactive contamination

Author:
Gulin, Sergey B.; Proskurnin, Vladislav Yu; Sidorov, Ilya G.
Source:
Journal of environmental radioactivity 2019 v.203 pp. 154-162
ISSN:
0265-931X
Subject:
tracer techniques,   etc   ; accidents; basins; cesium; radioactivity; radionuclides; sediments; Black Sea;     Show all 8 Subjects
Abstract:
... The combined use of artificial (137Cs, 238,239+240,241Pu, 241Am) and naturally occurring (210Pb/226Ra, 40K) radionuclides as tracers for dating of the Black Sea sediments has allowed to reveal the recent increase in radioactive contamination of this basin with 137Cs after the Chernobyl accident. This is presumably caused by the prolonged input of the man-made radionuclides that showed a rise in th ...
DOI:
10.1016/j.jenvrad.2019.03.016

10. Troubleshooting in a full-scale wastewater treatment plant: what can be learnt from tracer tests

Author:
Collivignarelli, M. C.; Bertanza, G.; Abbà, A.; Damiani, S.
Source:
International journal of environmental science and technology 2019 v.16 no.7 pp. 3455-3466
ISSN:
1735-1472
Subject:
tracer techniques,   etc   ; denitrification; foaming; hydrodynamics; mixers; sludge; wastewater treatment;     Show all 7 Subjects
Abstract:
... The experimental assessment of the actual reactor hydrodynamic behavior is aimed at detecting possible deviations from the design configuration, as well as suggesting corrective/improving modifications, efficacy of which can be also assessed in the aftermath. The hydrodynamic scheme can be defined by means of tracer tests (stimulus–response method) used for detecting the residence time distributio ...
DOI:
10.1007/s13762-018-2032-0

11. Ultrasonic characterisation of particle retention by a double porosity medium

Author:
Bai, Ruonan; Alem, Abdellah; Franklin, Hervé; Tinel, Alain; Wang, Huaqing; Kachkouch, Fatima; Taibi, Said; Bizet, Laurent
Source:
Environmental technology 2019 v.40 no.9 pp. 1166-1177
ISSN:
1479-487X
Subject:
tracer techniques,   etc   ; filtration; particle size distribution; porosity; porous media; ultrasonics;     Show all 6 Subjects
Abstract:
... A study was undertaken to characterise the evolution of the clogging of various porous media during filtration experiments. Long-term tracer tests were carried out at various flow velocities. To highlight the effects of intraporosity on transport and retention mechanisms, both single porosity and double porosity media (DPM) were used. The presence of matrix porosity in the two investigated DPM pro ...
DOI:
10.1080/09593330.2017.1417494

12. Channel network concept: an integrated approach to visualize solute transport in fractured rocks

Author:
Shahkarami, Pirouz; Neretnieks, Ivars; Moreno, Luis; Liu, Longcheng
Source:
Hydrogeology journal 2019 v.27 no.1 pp. 101-119
ISSN:
1431-2174
Subject:
tracer techniques,   etc   ; diffusivity; equations; hydrogeology; models; prediction; rocks; solutes; uncertainty;     Show all 9 Subjects
Abstract:
... The advection-dispersion equation, ADE, has commonly been used to describe solute transport in fractured rock. However, there is one key question that must be addressed before the mathematical form of the so-called Fickian dispersion that underlies the ADE takes on physical meaning in fractures. What is the required travel distance, or travel time, before the Fickian condition is met and the ADE b ...
DOI:
10.1007/s10040-018-1855-6

13. Elastohydrodynamic lubricant flow with nanoparticle tracking

Author:
Jeffreys, S.; di Mare, L.; Liu, X.; Morgan, N.; Wong, J. S. S.
Source:
RSC advances 2019 v.9 no.3 pp. 1441-1450
ISSN:
2046-2069
Subject:
tracer techniques,   etc   ; image analysis; lubricants; nanoparticles; rheological properties; rheology; velocimetry;     Show all 7 Subjects
Abstract:
... Lubricants operating in elastohydrodynamic (EHD) contacts exhibit local variations in rheological properties when the contact pressure rises. Direct evidence of this behaviour has only been obtained by examining through-thickness velocity profiles U(z) of lubricants in a contact using luminescence-based imaging velocimetry. In the present study, nanoparticles (NPs) are added to polybutene (PB) as ...
DOI:
10.1039/c8ra09396b

14. PTV-Stream: A simplified particle tracking velocimetry framework for stream surface flow monitoring

Author:
Tauro, Flavia; Piscopia, Rodolfo; Grimaldi, Salvatore
Source:
Catena 2019 v.172 pp. 378-386
ISSN:
0341-8162
Subject:
tracer techniques,   etc   ; algorithms; monitoring; overland flow; stream flow; streams; velocimetry;     Show all 7 Subjects
Abstract:
... Particle tracking velocimetry (PTV) is a promising image-based approach for remote streamflow measurements in natural environments. However, most PTV approaches require highly-defined round-shaped tracers, which are often difficult to observe outdoors. PTV-Stream offers a versatile alternative to cross-correlation-based PTV by affording the identification and tracking of features of any shape tran ...
DOI:
10.1016/j.catena.2018.09.009

15. A Straightforward Random Walk Model for Fast Push‐Pull Tracer Test Evaluation

Author:
Klotzsch, Stephan; Binder, Martin; Händel, Falk
Source:
Ground water 2017 v.55 no.1 pp. 129-135
ISSN:
0017-467X
Subject:
tracer techniques,   etc   ; algorithms; models;     Show all 3 Subjects
Abstract:
... In this article, we present a straightforward random walk model for fast evaluation of push‐pull tracer tests. By developing an adaptive algorithm, we overcome the problem of manually defining how many particles have to be used to simulate the transport problem. Beside this, we validate the random walk model by evaluating a push‐pull tracer test with drift phase and confirm the results with MT3DMS ...
DOI:
10.1111/gwat.12438

16. Tracers used in granular systems: Review

Author:
Hernández, Luis G.; Pérez, Javier García; Gaytán-Martínez, Marcela
Source:
Powder technology 2018 v.340 pp. 274-289
ISSN:
0032-5910
Subject:
tracer techniques,   etc   ; hydrology; industry; powders; tomography;     Show all 5 Subjects
Abstract:
... The study and understanding of the dynamic phenomena of particles in a granular system is crucial to define the optimal parameters of operation, mix quality and key controls of processes. There are different kinds of methodologies to screen the performance of mix process since sample extractions until tomographic techniques in real time. Some of these methods are based on the introduction of parti ...
DOI:
10.1016/j.powtec.2018.09.025

17. Analytical model for advective-dispersive transport involving flexible boundary inputs, initial distributions and zero-order productions

Author:
Chen, Jui-Sheng; Li, Loretta Y.; Lai, Keng-Hsin; Liang, Ching-Ping
Source:
Journal of hydrology 2017 v.554 pp. 187-199
ISSN:
0022-1694
Subject:
tracer techniques,   etc   ; hydrology; models; solutes;     Show all 4 Subjects
Abstract:
... A novel solution method is presented which leads to an analytical model for the advective-dispersive transport in a semi-infinite domain involving a wide spectrum of boundary inputs, initial distributions, and zero-order productions. The novel solution method applies the Laplace transform in combination with the generalized integral transform technique (GITT) to obtain the generalized analytical s ...
DOI:
10.1016/j.jhydrol.2017.08.050

18. Correction: Fluorescent natural products as probes and tracers in biology

Author:
Duval, Romain; Duplais, Christophe
Source:
Natural product reports 2017 v.34 no.3 pp. 329
ISSN:
1460-4752
Subject:
tracer techniques,   etc   ; fluorescence; fluorescent dyes;     Show all 3 Subjects
Abstract:
... Correction for ‘Fluorescent natural products as probes and tracers in biology’ by Romain Duval et al., Nat. Prod. Rep., 2017, DOI: 10.1039/c6np00111d. ...
DOI:
10.1039/c7np90008b

19. Evaluation of liquid and solid phase mixing in Chinese dome digesters using residence time distribution (RTD) technique

Author:
Jegede, A.O.; Zeeman, G.; Bruning, H.
Source:
Renewable energy 2019 v.143 pp. 501-511
ISSN:
0960-1481
Subject:
tracer techniques,   etc   ; anaerobic digestion; impellers; methane production; renewable energy sources; total solids;     Show all 6 Subjects
Abstract:
... The Residence Time Distribution (RTD) technique was applied to evaluate mixing of liquid and solid phases in laboratory scale Chinese dome digesters mixed via hydraulic variation. To achieve this purpose, six laboratory scales digesters with different mixing modes and two total solids (TS) concentrations using appropriate tracers were studied over a theoretical hydraulic retention time (HRT) of 30 ...
DOI:
10.1016/j.renene.2019.04.160

20. Evaluation of factors influencing secondary organic carbon (SOC) estimation by CO and EC tracer methods

Author:
Zhang, Qi; Sarkar, Sayantan; Wang, Xuemei; Zhang, Jinpu; Mao, Jingying; Yang, Liming; Shi, Yiwen; Jia, Shiguo
Source:
The Science of the total environment 2019 v.686 pp. 915-930
ISSN:
0048-9697
Subject:
tracer techniques,   etc   ; Monte Carlo method; aerosols; carbon monoxide; organic carbon; ozone; uncertainty;     Show all 7 Subjects
Abstract:
... Secondary organic carbon (SOC) is known to account for a substantial fraction of fine-mode carbonaceous aerosol. Owing to a limited understanding of SOC formation processes and the absence of direct measurement methods, SOC concentrations are mostly estimated using a tracer-based method utilizing either elemental carbon (EC) or carbon monoxide (CO) as tracers. The performance of these tracer-based ...
DOI:
10.1016/j.scitotenv.2019.05.402