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Author Sedghi, M.M.; Zhan, H. url  openurl
  Title On the discharge variation of a qanat in an alluvial fan aquifer Type Journal Article
  Year 2022 Publication Journal of Hydrology Abbreviated Journal  
  Volume 610 Issue Pages 127922  
  Keywords (up) Analytical solution, Wedge-shaped aquifer, Image well, Areal recharge  
  Abstract Qanat is a passive (unpumped) horizontal well (or a slant well with a very mild inclined angle) that is capable of extracting water from aquifers by gravity. Many qanats are constructed along the radius of the alluvial fan wedge-shaped aquifers. Analytical modeling of such a qanat-aquifer system provides great benefit for quickly screening different designs of qanats and accessing the performance of qanat discharge in the field. The previous analytical modeling of discharge of qanats, however, did not consider the wedge-shaped aquifers. Thus, the goal of this research is to obtain semi-analytical solutions of discharge variations of qanats in alluvial fan aquifers with nearby pumping wells, subjected to areal recharges due to rainfall. The uniform head boundary is considered inside the qanat (because of its enormous permeability in respect to the background aquifer). The influences of the aquifer lateral boundaries on discharge of qanat and its sensitivity to hydraulic and geometric parameters are explored. The influences of the lateral boundaries on the discharge of qanat due to areal recharge and nearby pumping wells discharge are also explored. The results of this study can be utilized for multiple purposes: 1) to predict the discharge of qanat in an alluvial fan aquifer and explore the influences of the areal recharge and nearby pumping well discharge; 2) to estimate the hydraulic parameters of the alluvial fan aquifer depleted by a qanat; 3) to determine the location of the nearby pumping well to minimize its influences on the discharge of a qanat; 4) to calculate the water budgets of aquifers depleted by qanats and pumping wells and replenished by areal recharge among other applications. This paper is an extension to the work presented by Sedghi and Zhan (2020) (which concerns an infinite unconfined aquifer) for an unconfined alluvial fan aquifer setting.  
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  ISSN 0022-1694 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Sedghi2022127922 Serial 267  
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Author Kumar, V.; Setia, R.; Pandita, S.; Singh, S.; Mitran, T. url  openurl
  Title Assessment of U and As in groundwater of India: A meta-analysis Type Journal Article
  Year 2022 Publication Chemosphere Abbreviated Journal  
  Volume 303 Issue Pages 135199  
  Keywords (up) Arsenic, Geology, Groundwater, Health risk, Soil texture, Uranium  
  Abstract More than 2.5 billion people depend upon groundwater worldwide for drinking, and giving quality water has become one of the great apprehensions of human culture. The contamination of Uranium (U) and Arsenic (As) in the groundwater of India is gaining global attention. The current review provides state-of-the-art groundwater contamination with U and As in different zones of India based on geology and soil texture. The average concentration of U in different zones of India was in the order: West Zone (41.07 μg/L) \textgreater North Zone (37.7 μg/L) \textgreater South Zone (13.5 μg/L)\textgreater Central Zone (7.4 μg/L) \textgreater East Zone (5.7 μg/L) \textgreaterSoutheast Zone (2.4 μg/L). The average concentration of As in groundwater of India is in the order: South Zone (369.7 μg/L)\textgreaterCentral Zone (260.4 μg/L)\textgreaterNorth Zone (67.7 μg/L)\textgreaterEast Zone (60.3 μg/L)\textgreaterNorth-east zone (9.78 μg/L)\textgreaterWest zone (4.14 μg/L). The highest concentration of U and As were found in quaternary sediments, but U in clay skeletal and As in loamy skeletal. Results of health risk assessment showed that the average health quotient of U in groundwater for children and adults was less than unity. In contrast, it was greater than unity for As posing a harmful impact on human health. This review provides the baseline data regarding the U and As contamination status in groundwater of India, and appropriate, effective control measures need to be taken to control this problem.  
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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 @ kumar_assessment_2022 Serial 161  
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Author Ren, Y.; Yang, X.; Hu, X.; Wei, J.; Tang, C. url  openurl
  Title Mineralogical and geochemical evidence for biogenic uranium mineralization in northern Songliao Basin, NE China Type Journal Article
  Year 2022 Publication Ore Geology Reviews Abbreviated Journal  
  Volume 141 Issue Pages 104556  
  Keywords (up) Bacterial sulfate reduction, In-situ S isotope of pyrite, Northern Songliao basin, Sandstone-type uranium deposit, Sifangtai Formation  
  Abstract The sandstone-hosted uranium mineralization areas in the Sanzhao Sag of the northern Songliao Basin have been newly identified. The target stratum is the Upper Cretaceous Sifangtai Formation and the uranium mineralization mainly occurs in the bottom of Sifangtai Formation, corresponding to channel sand bodies in meandering river system, characterized by medium to fine-grained sandstone. This study proposes the uranium metallogenic model through petrographic observation, whole rock geochemistry, mineralogical study of uranium occurrence form (SEM), organic matter rock–eval pyrolysis analysis (REP) and in-situ sulfur isotope determination of different generations of pyrite by LA-MC-ICP-MS. Compared with the sandstones collected in barren reduction and oxidization zones, the mineralized sandstones show obvious increase in the contents of TOC, total sulfur, Y and U. Petrographic observations indicate that organic matters are mainly inherited from land plants. REP data display that the organic matter (OM) disseminated in the sandstone has very low hydrogen index (HI) from around 0 to 21 mg HC/g TOC and varied oxygen index (OI) from 44 to 115 mg CO2/g TOC, corresponding to Type Ⅳ kerogen (degraded kerogen). There are two types of coffinite with different grain size, micro-particles (μm-sized) and large aggregates (generally up to 100 μm) respectively. The coffinite micro spherules exhibit short rod-like or worm-like morphology occurring in clay matrix and cell cavities in degradofusinite or around subidiomorphic-idiomorphic pyrite. The coarse-grained coffinite contains other mineral facies (e.g. pyrite, quartz) and some of large coffinite aggregates display thrombolite-type microbial structures. The irregular pyrite relict particles in coarse-grained colloidal coffinite have light sulfur isotope compositions characterized by δ34S values from –39.96‰ to –49.89‰. The δ34S values of colloidal pyrite in replacement of OM or of the sub-idiomorphic FeS2 cement filling in the cavities of OM range from –52.77‰ to –13.88‰. Some of sub-idiomorphic pyrite cement and idiomorphic crystal have the heavier signature from – 27.06‰ to + 14.23‰. The light sulfur isotope signature suggests that the sulfur originates from bacterial sulfate reduction (BSR). The OM replacement by pyrite and the highest OI values recorded by REP in uranium mineralized samples are lines of evidence of biodegradation. Bacteria use the organic matter as food source and produce isotopically light reduced sulfur species. Oxygenated uranium-bearing waters infiltrated through the denudated windows at Daqing placanticline into the porous reduced sandstones deposited in the Sanzhao Sag. Uranium was indirectly reduced by BSR-derived iron disulfides or directly reduced by sulfate-reducing bacteria.  
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  ISSN 0169-1368 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ ren_mineralogical_2022 Serial 144  
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Author Emparanza, A.R.; Kampmann, R.; Caso, F.D.; Morales, C.; Nanni, A. url  openurl
  Title Durability assessment of GFRP rebars in marine environments Type Journal Article
  Year 2022 Publication Construction and Building Materials Abbreviated Journal  
  Volume 329 Issue Pages 127028  
  Keywords (up) Composite FRP rebar, Durability, Service life, Marine structures, Reinforced concrete  
  Abstract Technologies developed over the last two decades have facilitated the use of glass fiber reinforced polymer (GFRP) bars as internal reinforcement for concrete structures, specially in coastal environments, mainly due to their corrosion resistance. To-date, most durability studies have focused on a single mechanical parameter (tensile strength) and a single aging environment (exposure to high alkalinity). However, knowledge gaps exists in understanding how other mechanical parameters and relevant conditioning environments may affect the durability of GFRP bars. To this end, this study assesses the durability for different physio-mechanical properties of GFRP rebars, post exposure to accelerated conditioning in seawater. Six different GFRP rebar types were submerged in seawater tanks, at various temperatures (23°C, 40°C and 60°C) for different time periods (60, 120, 210 and 365 days). In total six different physio-mechanical properties were assessed, including: tensile strength, E-modulus, transverse and horizontal shear strength, micro-structural composition and lastly, bond strength. It was inferred that rebars with high moisture absorption resulted in poor durability, in that it affected mainly the tensile strength. Based on the Arrhenius model, at 23°C all the rebars that met the acceptance criteria by ASTM D7957 are expected to retain 85% of the tensile strength capacity.  
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  Series Volume Series Issue Edition  
  ISSN 0950-0618 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Ruizemparanza2022127028 Serial 83  
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Author Paradis, C.J.; Hoss, K.N.; Meurer, C.E.; Hatami, J.L.; Dangelmayr, M.A.; Tigar, A.D.; Johnson, R.H. url  openurl
  Title Elucidating mobilization mechanisms of uranium during recharge of river water to contaminated groundwater Type Journal Article
  Year 2022 Publication Journal of Contaminant Hydrology Abbreviated Journal  
  Volume 251 Issue Pages 104076  
  Keywords (up) Desorption, Dissolution, Groundwater, Surface water, Tracer, Uranium  
  Abstract The recharge of stream water below the baseflow water table can mobilize groundwater contaminants, particularly redox-sensitive and sorptive metals such as uranium. However, in-situ tracer experiments that simulate the recharge of stream water to uranium-contaminated groundwater are lacking, thus limiting the understanding of the potential mechanisms that control the mobility of uranium at the field scale. In this study, a field tracer test was conducted by injecting 100 gal (379 l) of oxic river water into a nearby suboxic and uranium-contaminated aquifer. The traced river water was monitored for 18 days in the single injection well and in the twelve surrounding observation wells. Mobilization of uranium from the solid to the aqueous phase was not observed during the tracer test despite its pre-test presence being confirmed on the aquifer sediments from lab-based acid leaching. However, strong evidence of oxidative immobilization of iron and manganese was observed during the tracer test and suggested that immobile uranium was likely in its oxidized state as U(VI) on the aquifer sediments; these observations ruled out oxidation of U(IV) to U(VI) as a potential mobilization mechanism. Therefore, desorption of U(VI) appeared to be the predominant potential mobilization mechanism, yet it was clearly not solely dependent on concentration as evident when considering that uranium-poor river water (\textless0.015 mg/L) was recharged to uranium-rich groundwater (≈1 mg/L). It was possible that uranium desorption was limited by the relatively higher pH and lower alkalinity of the river water as compared to the groundwater; both factors favor immobilization. However, it was likely that the immobile uranium was associated with a mineral phase, as opposed to a sorbed phase, thus desorption may not have been possible. The results of this field tracer study successfully ruled out two common mobilization mechanisms of uranium: (1) oxidative dissolution and (2) concentration-dependent desorption and ruled in the importance of advection, dispersion, and the mineral phase of uranium.  
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  ISSN 0169-7722 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ paradis_elucidating_2022 Serial 135  
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Author Zhang, H.; Gao, J.; Xu, L.; Zhang, X. url  openurl
  Title Case studies of radioactivity of drilling mud for in situ leaching uranium mining in China Type Journal Article
  Year 2022 Publication Journal of Environmental Radioactivity Abbreviated Journal  
  Volume 251-252 Issue Pages 106982  
  Keywords (up) Drilling mud, Exemption management, In situ leaching, Radioactivity  
  Abstract The drilling mud from in situ leaching uranium mining is a type of low-radioactivity waste that contains natural nuclides and other harmful substances. In order to determine whether the drilling mud can meet the requirements of radioactive exemption management standards, field investigations and data simulations were conducted in this study. Two typical uranium mines were selected for onsite investigations. Drilling mud from different layers (i.e., the upper covering layer and ore-bearing layer) and from different stages (e.g., logging stage mud, drilling expansion stage mud, and mixed mud) was sampled. For each sample, the 238U and 226Ra concentrations of the solid components and the U and 226Ra concentrations of the supernatant were analyzed. The results revealed that the highest 238U and 226Ra concentrations of the solid components were 4122 Bq/kg and 4077 Bq/kg, while the 238U and 226Ra concentrations of the mixed drilling mud were all less than 300 Bq/kg. A radioactivity estimation model was established for scenario analysis. Exemption management screening lines of waste drilling mud, which can be used to classify and treat the drilling project according to the deposit’s grade and conditions, were proposed for in situ leaching drilling projects.  
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  Series Volume Series Issue Edition  
  ISSN 0265-931x ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ zhang_case_2022 Serial 191  
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Author Chen, Y.; Hong, Y.; Huang, D.; Dai, X.; Zhang, M.; Liu, Y.; Xu, Z. url  openurl
  Title Risk assessment management and emergency plan for uranium tailings pond Type Journal Article
  Year 2022 Publication Journal of Radiation Research and Applied Sciences Abbreviated Journal  
  Volume 15 Issue 3 Pages 83-90  
  Keywords (up) Emergency management, Interpreted structural model (ISM), Resilience, Risk coupling, Uranium tailings pond  
  Abstract The safety of uranium tailings pond is closely related to social stability and economic development, so it is necessary to improve the emergency management of uranium tailings pond to ensure its safety by adjusting the emergency plan. The Interpretive Structural Model (ISM) is used to analyze the structural relationship between the main risk factors leading to the occurrence of emergencies. The results show that attention should be paid to the risk factors originating from humans and infrastructures, and effective management measures should be adopted in the process of emergency management, for example, people build tighter employee access system, clarify the responsibilities of employees at all levels, and improve monitoring and organizational means. According to the results of ISM analysis, a structural risk control system can be constructed, and a defensive barrier that can effectively block the risk coupling transmission can be designed to prevent the risk from being transformed into an event. For other risks, system resilience management should be strengthened to respond to risks. The process is set as emergency response and accident response. Different management objects use different management methods to make emergency management work efficiently.  
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  ISSN 1687-8507 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ chen_risk_2022 Serial 128  
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Author Xiao, L.; Robinson, M.; O’Connor, M. url  openurl
  Title Woodland’s role in natural flood management: Evidence from catchment studies in Britain and Ireland Type Journal Article
  Year 2022 Publication Science of The Total Environment Abbreviated Journal  
  Volume 813 Issue Pages 151877  
  Keywords (up) Forest harvesting, Streamflow, Natural flood management, Before-after-control-impact, Evidence-based forest impact  
  Abstract Despite the attention currently given to the potential environmental benefits of large-scale forest planting, there is a shortage of clear observational evidence regarding the effects on river flows, and what there is has often been contradictory or inconclusive. This paper presents three independently conducted paired-catchment forestry studies covering 66 station-years of flow measurements in the UK and Ireland. In each case coniferous evergreen trees were removed from one catchment with minimal soil disturbance while the adjoining control catchment was left unchanged. Trees were removed from 20% – 90% of the three experimental basins. Following woodland removal there was an increase in dry weather baseflow at all sites. Baseflows increased by about 8% after tree removal from a quarter of the Hore basin and by 41% for the near-total cut at Howan. But the changes were more complex for peak flows. Tree harvesting increased the smallest and most frequent peak storm flows, indicating that afforestation would lead to the suppression of such events. This was however restricted to events well below the mean annual flood, indicating that the impact of forests upon the largest and most damaging floods is likely to be limited. Whilst a forest cover can be effective in mitigating small and frequent stormflows it should never be assumed to provide protection against major flood events.  
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  ISSN 0048-9697 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Xiao2022151877 Serial 241  
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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 1175-1184  
  Keywords (up) 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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  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 Jana, A.; Unni, A.; Ravuru, S.S.; Das, A.; Das, D.; Biswas, S.; Sheshadri, H.; De, S. url  openurl
  Title In-situ polymerization into the basal spacing of LDH for selective and enhanced uranium adsorption: A case study with real life uranium alkaline leach liquor Type Journal Article
  Year 2022 Publication Chemical Engineering Journal Abbreviated Journal  
  Volume 428 Issue Pages 131180  
  Keywords (up) In-situ polymerization, Layered double hydroxide, Leach liquor, Uranium adsorption, Uranium recovery  
  Abstract Uranium is used as a fuel for nuclear power plant and can be extracted from different ores, mainly acidic (silicious ore) and alkaline (carbonate ore). Recovery of uranium through acid leaching from silicious ore is well established, whereas, alkaline leaching from carbonate ore is challenging due to the excessive salinity of leach liquor and high concentration of carbonate, bicarbonate and sulphate. Herein, two monomers, acrylic acid (AA) and N, N-methylene bisacrylamide (BAM), selective towards uranyl were intercalated in-situ into the interlayer, followed by their polymerization and cross-linking to form novel polymer intercalated hybrid layered double hydroxide (LDH). The LDH acts as a backbone to overcome coiling and swelling of polymer and anchors them as free-standing. Various parameters, like, the type of metal ions, monomer ratio (AA: BAM) and metal ion ratio (M2+:M3+), were studied to determine the optimum conditions for effective intercalation and polymerization of monomers. Magnesium aluminum (MgAl) LDH with a cross-linked polymer having a monomer ratio of 3:2 (AA: BAM) as intercalating species showed maximum efficiency of uranyl adsorption (1456 mg/g at 30 °C) with highest capacity so far. The distribution coefficient (Kd, l/mg) in the order of 105 suggested that the adsorbent was highly selective for uranyl in the presence of different cations, anions and humic acid. The adsorbent extracts uranium effectively and selectively from a real-life alkaline leach liquor with an efficiency of 96% at 5 g/l dose. Uranium can be recovered from the adsorbent in the form of sodium di-uranate using 2(M) NaOH and was reused for eight cycles.  
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  ISSN 1385-8947 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ jana_-situ_2022 Serial 209  
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