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Author Wilson, G.B.; McNeill, G.W. url  openurl
  Title Noble gas recharge temperatures and the excess air component Type Journal Article
  Year 1997 Publication Applied Geochemistry Abbreviated Journal  
  Volume 12 Issue 6 Pages (up) 747-762  
  Keywords  
  Abstract The calculation of a groundwater recharge temperature based on the dissolved concentrations of Ne, Ar, Kr and Xe requires a correction for noble gas supersaturation due to excess air entrainment. This entrainment is commonly attributed to the recharge process or to air contamination at the wellhead during sample collection. With the exception of some local studies, most work has concentrated on interpretation of the recharge temperature or quantification of the radiogenic content for palaeoclimatic and dating purposes. The magnitude and source of the excess air is not directly relevant to these studies and so is often ignored. In this work, excess air Ne and other data have been calculated from new and published noble gas data sets for several groundwater systems. For younger groundwaters which have been recharged under one broad climatic regime, the amount of air entrainment increases according to lithology in the order granites, sandstones and limestones respectively. A negative correlation between precipitation and excess air entrainment is identified in at least one aquifer, and some of the mechanisms which may influence the entrainment process are discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0883-2927 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Wilson1997747 Serial 281  
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Author YI, Z.-ji; LIAN, B.; YANG, Y.-qun; ZOU, J.-ling url  openurl
  Title Treatment of simulated wastewater from in situ leaching uranium mining by zerovalent iron and sulfate reducing bacteria Type Journal Article
  Year 2009 Publication Transactions of Nonferrous Metals Society of China Abbreviated Journal  
  Volume 19 Issue Pages (up) 840  
  Keywords basification, sulfate, sulfate reducing bacteria (SRB), uranium, wastewater, zerovalent iron (ZVI)  
  Abstract Batch and column experiments were conducted to determine whether zerovalent iron (ZVI) and sulfate reducing bacteria (SRB) can function synergistically and accelerate pollutant removal. Batch experiments suggest that combining ZVI with SRB can enhance the removal of U(?) synergistically. The removal rate of U(?) in the ZVI+SRB combining system is obviously higher than the total rate of ZVI system and SRB system with a difference of 13.4% at t=2 h and 29.9% at t=4 h. Column experiments indicate that the reactor filled with both ZVI and SRB biofilms is of better performance than the SRB bioreactor in wastewater basification, desulfurization and U(?) fixation. The results imply that the ZVI+SRB permeable reactive barrier may be a promising method for treating subsurface uranium contamination.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1003-6326 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ yi_treatment_2009 Serial 206  
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Author Liesch, T.; Hinrichsen, S.; Goldscheider, N. url  openurl
  Title Uranium in groundwater — Fertilizers versus geogenic sources Type Journal Article
  Year 2015 Publication Science of The Total Environment Abbreviated Journal  
  Volume 536 Issue Pages (up) 981-995  
  Keywords Drinking water, Fertilizer, Geogenic background, Groundwater, Uranium  
  Abstract Due to its radiological and toxicological properties even at low concentration levels, uranium is increasingly recognized as relevant contaminant in drinking water from aquifers. Uranium originates from different sources, including natural or geogenic, mining and industrial activities, and fertilizers in agriculture. The goal of this study was to obtain insights into the origin of uranium in groundwater while differentiating between geogenic sources and fertilizers. A literature review concerning the sources and geochemical processes affecting the occurrence and distribution of uranium in the lithosphere, pedosphere and hydrosphere provided the background for the evaluation of data on uranium in groundwater at regional scale. The state of Baden-Württemberg, Germany, was selected for this study, because of its hydrogeological and land-use diversity, and for reasons of data availability. Uranium and other parameters from N=1935 groundwater monitoring sites were analyzed statistically and geospatially. Results show that (i) 1.6% of all water samples exceed the German legal limit for drinking water (10μg/L); (ii) The range and spatial distribution of uranium and occasional peak values seem to be related to geogenic sources; (iii) There is a clear relation between agricultural land-use and low-level uranium concentrations, indicating that fertilizers generate a measurable but low background of uranium in groundwater.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0048-9697 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ liesch_uranium_2015 Serial 145  
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Author Davila, P.; Külls, C. openurl 
  Title Combined application of 85-Kr, 39-Ar with CFCs in contaminated aquifers Type Journal Article
  Year 2009 Publication EGU Geophysical Abstracts Abbreviated Journal  
  Volume Issue Pages (up) 1074  
  Keywords  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Davila2009combined Serial 51  
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Author Castro, M.C.; Stute, M.; Schlosser, P. url  openurl
  Title Comparison of 4He ages and 14C ages in simple aquifer systems: implications for groundwater flow and chronologies Type Journal Article
  Year 2000 Publication Applied Geochemistry Abbreviated Journal  
  Volume 15 Issue 8 Pages (up) 1137-1167  
  Keywords  
  Abstract 4He concentrations in excess of the solubility equilibrium with the atmosphere by up to two to three orders of magnitude are observed in the Carrizo Aquifer in Texas, the Ojo Alamo and Nacimiento aquifers in the San Juan Basin, New Mexico, and the Auob Sandstone Aquifer in Namibia. A simple 4He accumulation model is applied to explain these excess 4He concentrations in terms of both in situ production and a crustal flux across the bottom layer of the aquifer. Results from the model simulations suggest variability in the 4He fluxes, ranging from 6×10−6 cm3 STP cm−2 yr−1 for the Auob Sandstone Aquifer to 3.6×10−7 cm3 STP cm−2 yr−1 for the Carrizo aquifer. For the Ojo Alamo and Nacimiento aquifers an intermediate value of 3×10−6 cm3 STP cm−2 yr−1 was estimated. The contribution of in-situ produced 4He to the measured concentrations was also estimated. This contribution is negligible for the Auob Sandstone Aquifer as compared with both the concentrations measured at the top and bottom of the aquifer for most of the pathway. In the Carrizo aquifer, in-situ produced 4He contributes 27.5% and 15.4%, to the total 4He observed at the top and bottom of the aquifer, respectively. For both aquifers of the San Juan Basin in-situ production almost entirely dominates the 4He concentrations at the top of the aquifer for most of the pathway. In contrast, the internal production is negligible as compared with the measured concentrations at the bottom of these aquifers, reaching, at most, 1.1%. The model simulations require an exponential decrease in the horizontal velocity of the water with increasing recharge distance to reproduce the distribution of 4He in these aquifers. For the Auob Sandstone Aquifer the highest range in the velocity values is obtained (25 to 0.4 m yr−1). The simulations for the Carrizo aquifer and both aquifers located in the San Juan Basin require velocities varying from 4 to 0.1 m yr−1, and from 2 to 0.3 m yr−1, respectively. For each aquifer, average permeability values were also estimated. They are generally in agreement with results obtained from pumping tests, hydrodynamic modeling and previous 14C measurements. On the basis of the results obtained by calibrating the model with the measured 4He concentrations, the mean water residence times were estimated. They agree reasonably well with 14C ages. When applied as chronologies for noble gas temperatures in the same aquifers, the calculated 4He ages allow the identification of three different climate periods similar to those previously identified using 14C ages: (1) the Holocene period (0–10 Ka BP), (2) the Last Glacial Maximum (≈18 Ka BP), and (3) the preceeding period (30–150 Ka BP).  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0883-2927 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ castro_comparison_2000 Serial 109  
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Author Zeng, S.; Shen, Y.; Sun, B.; Tan, K.; Zhang, S.; Ye, W. url  openurl
  Title Fractal kinetic characteristics of uranium leaching from low permeability uranium-bearing sandstone Type Journal Article
  Year 2022 Publication Nuclear Engineering and Technology Abbreviated Journal  
  Volume 54 Issue 4 Pages (up) 1175-1184  
  Keywords Fractal characteristics, In-situ leaching, Leaching kinetics, Pore structure, Uranium mine  
  Abstract The pore structure of uranium-bearing sandstone is one of the critical factors that affect the uranium leaching performance. In this article, uranium-bearing sandstone from the Yili Basin, Xinjiang, China, was taken as the research object. The fractal characteristics of the pore structure of the uranium-bearing sandstone were studied using mercury intrusion experiments and fractal theory, and the fractal dimension of the uranium-bearing sandstone was calculated. In addition, the effect of the fractal characteristics of the pore structure of the uranium-bearing sandstone on the uranium leaching kinetics was studied. Then, the kinetics was analyzed using a shrinking nuclear model, and it was determined that the rate of uranium leaching is mainly controlled by the diffusion reaction, and the dissolution rate constant (K) is linearly related to the pore specific surface fractal dimension (DS) and the pore volume fractal dimension (DV). Eventually, fractal kinetic models for predicting the in-situ leaching kinetics were established using the unreacted shrinking core model, and the linear relationship between the fractal dimension of the sample’s pore structure and the dissolution rate during the leaching was fitted.  
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  Corporate Author Thesis  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1738-5733 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ zeng_fractal_2022 Serial 193  
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Author Klimkova, S.; Cernik, M.; Lacinova, L.; Filip, J.; Jancik, D.; Zboril, R. url  openurl
  Title Zero-valent iron nanoparticles in treatment of acid mine water from in situ uranium leaching Type Journal Article
  Year 2011 Publication Chemosphere Abbreviated Journal  
  Volume 82 Issue 8 Pages (up) 1178-1184  
  Keywords Acid mine water, Contaminant removal, Surface stabilizing shell, Water treatment, Zero-valent iron nanoparticles  
  Abstract Acid mine water from in situ chemical leaching of uranium (Straz pod Ralskem, Czech Republic) was treated in laboratory scale experiments by zero-valent iron nanoparticles (nZVI). For the first time, nZVI were applied for the treatment of the real acid water system containing the miscellaneous mixture of pollutants, where the various removal mechanisms occur simultaneously. Toxicity of the treated saline acid water is caused by major contaminants represented by aluminum and sulphates in a high concentration, as well as by microcontaminants like As, Be, Cd, Cr, Cu, Ni, U, V, and Zn. Laboratory batch experiments proved a significant decrease in concentrations of all the monitored pollutants due to an increase in pH and a decrease in oxidation–reduction potential related to an application of nZVI. The assumed mechanisms of contaminants removal include precipitation of cations in a lower oxidation state, precipitation caused by a simple pH increase and co-precipitation with the formed iron oxyhydroxides. The possibility to control the reaction kinetics through the nature of the surface stabilizing shell (polymer vs. FeO nanolayer) is discussed as an important practical aspect.  
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  Series Volume Series Issue Edition  
  ISSN 0045-6535 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ klimkova_zero-valent_2011 Serial 196  
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Author Robati, A.; Barani, G.A. url  openurl
  Title Modeling of water surface profile in subterranean channel by differential quadrature method (DQM) Type Journal Article
  Year 2009 Publication Applied Mathematical Modelling Abbreviated Journal  
  Volume 33 Issue 3 Pages (up) 1295-1305  
  Keywords Subterranean channel, Qanat, Differential quadrature method, Water surface profile, Porous media  
  Abstract This study, investigates the hydraulic of flow in a subterranean channel headspring. The continuity and momentum equations of flow in porous media considering real conditions were used and the basic equation of flow in a subterranean channel was resulted. This equation is very similar to the spatially varied flow with increasing discharge. An equation, defining the hydraulic parameters of a subterranean channel section was adopted. Then differential quadrature method (DQM), was applied to the equation of flow in subterranean channel, consequently the water surface profile was resulted. To illustrate the rightness of model, the hydraulic parameters of flow in the Gavgard branch of the Joopar Goharriz Qanat were measured and the water surface profile was determined. This water surface profile was compared to the water surface profile computed by the model, which are in good agreement.  
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  Corporate Author Thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0307-904x ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Robati20091295 Serial 249  
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Author Liu, Z.; Tan, K.; Li, C.; Li, Y.; Zhang, C.; Song, J.; Liu, L. url  openurl
  Title Geochemical and S isotopic studies of pollutant evolution in groundwater after acid in situ leaching in a uranium mine area in Xinjiang Type Journal Article
  Year 2023 Publication Nuclear Engineering and Technology Abbreviated Journal  
  Volume 55 Issue 4 Pages (up) 1476-1484  
  Keywords Acid in situ leaching of uranium, Pollution evolution, Sulfate elimination, Sulfur isotopes analysis  
  Abstract Laboratory experiments and point monitoring of reservoir sediments have proven that stable sulfate reduction (SSR) can lower the concentrations of toxic metals and sulfate in acidic groundwater for a long time. Here, we hypothesize that SSR occurred during in situ leaching after uranium mining, which can impact the fate of acid groundwater in an entire region. To test this, we applied a sulfur isotope fractionation method to analyze the mechanism for natural attenuation of contaminated groundwater produced by acid in situ leaching of uranium (Xinjiang, China). The results showed that δ34S increased over time after the cessation of uranium mining, and natural attenuation caused considerable, area-scale immobilization of sulfur corresponding to retention levels of 5.3%–48.3% while simultaneously decreasing the concentration of uranium. Isotopic evidence for SSR in the area, together with evidence for changes of pollutant concentrations, suggest that area-scale SSR is most likely also important at other acid mining sites for uranium, where retention of acid groundwater may be strengthened through natural attenuation. To recapitulate, the sulfur isotope fractionation method constitutes a relatively accurate tool for quantification of spatiotemporal trends for groundwater during migration and transformation resulting from acid in situ leaching of uranium in northern China.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1738-5733 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ liu_geochemical_2023 Serial 192  
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Author Baram, S.; Ronen, Z.; Kurtzman, D.; Külls, C.; Dahan, O. url  doi
openurl 
  Title Desiccation-crack-induced salinization in deep clay sediment Type Journal Article
  Year 2013 Publication Hydrology and Earth System Sciences Abbreviated Journal  
  Volume 17 Issue 4 Pages (up) 1533  
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  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Copernicus GmbH Place of Publication Editor  
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  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Baram2013desiccation Serial 21  
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