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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 (down) 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 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  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ jana_-situ_2022 Serial 209  
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Author Lach, P.; Cathelineau, M.; Brouand, M.; Fiet, N. url  openurl
  Title (down) In-situ Isotopic and Chemical Study of Pyrite from Chu-Sarysu (Kazakhstan) Roll-front Uranium Deposit Type Journal Article
  Year 2015 Publication Procedia Earth and Planetary Science Abbreviated Journal  
  Volume 13 Issue Pages 207-210  
  Keywords LA-ICP-MS, pyrite, roll-front, SIMS, sulfur isotopy, traces elements, uranium  
  Abstract Pyrite is common in roll-front type uranium deposit in Chu-sarysu basin, Kazakhstan. Combined in-situ microstructural, isotopic and chemical analysis of pyrite indicates variation in precipitation conditions and in fluid composition. Broad-scale δ34S heterogeneity indicates a complex multi-facet evolution. First generation authigenic framboïdal aggregates are biogenic as demonstrated by the lowest δ34S values of -48‰ to -28‰. The latest generation pyrites are probably hydrothermal with greater δ34S variation (-30‰ to +12‰). This hydrothermal pyrite commonly displays variable enrichment of several trace elements especially As, Co and Ni. Strong variation in δ34S values and variable trace element enrichment is interpreted in terms of continuous variations in fluid composition.  
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  Series Volume Series Issue Edition  
  ISSN 1878-5220 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ lach_-situ_2015 Serial 182  
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Author Uhrie, J.L.; Drever, J.I.; Colberg, P.J.S.; Nesbitt, C.C. url  openurl
  Title (down) In situ immobilization of heavy metals associated with uranium leach mines by bacterial sulfate reduction Type Journal Article
  Year 1996 Publication Hydrometallurgy Abbreviated Journal  
  Volume 43 Issue 1 Pages 231-239  
  Keywords  
  Abstract Laboratory experiments with mixed populations of sulfate-reducing bactreria were shown to mediate the removal of milligrams/liter concentrations of uranium, selenium, arsenic and vanadium from aqueous solution via reduction, precipitation and adsorption. Results of laboratory experiments with active sulfidogenic biomass suggest that injection of sulfate and a source of carbon could enhance anaerobic microbial activity in and around uranium leach mines leading to in situ immobilization contaminating metals.  
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  Series Volume Series Issue Edition  
  ISSN 0304-386x ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ uhrie_situ_1996 Serial 197  
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Author de Jong, I.J.H.; Arif, S.S.; Gollapalli, P.K.R.; Neelam, P.; Nofal, E.R.; Reddy, K.Y.; Röttcher, K.; Zohrabi, N. url  openurl
  Title (down) Improving agricultural water productivity with a focus on rural transformation* Type Journal Article
  Year 2021 Publication Irrigation and Drainage Abbreviated Journal  
  Volume 70 Issue 3 Pages 458-469  
  Keywords irrigation efficiency, water productivity, rural transformation, efficacité de l’irrigation, productivité de l’eau, transformation rurale  
  Abstract ABSTRACT As a result of population growth, economic development and climate change, feeding the world and providing water security will require important changes in the technologies, institutions, policies and incentives that drive present-day water management, as captured in Goal 6.4 of the Millennium Development Goals. Irrigation is the largest and most inefficient water user, and there is an expectation that even small improvements in agricultural water productivity will improve water security. This paper argues that improvements in irrigation water productivity involves a complex and comprehensive rural transformation that goes beyond mere promotion of water saving technologies. Many of the measures to improve water productivity require significant changes in the production systems of farmers and in the support provided to them. Looking forward, water use and competition over water are expected to further increase. By 2025, about 1.8 billion people will be living in regions or countries with absolute water scarcity. Demand for water will rise exponentially, while supply becomes more erratic and uncertain, prompting the need for significant shifts of inter-sectoral water allocation to support continued economic growth. Advances in the use of remote sensing technologies will make it increasingly possible to cost-effectively and accurately estimate crop evapotranspiration from farmers’ fields.  
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  Call Number THL @ christoph.kuells @ https://doi.org/10.1002/ird.2451 Serial 89  
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Author Custódio, D.A.; Ghisi, E. url  openurl
  Title (down) Impact of residential rainwater harvesting on stormwater runoff Type Journal Article
  Year 2023 Publication Journal of Environmental Management Abbreviated Journal  
  Volume 326 Issue Pages 116814  
  Keywords Rainwater harvesting, Residential buildings, Stormwater runoff, Floods, Computer simulation  
  Abstract Population increase, climate change and soil impermeability are factors causing floods in large urban centres. Such places also always have water shortage problems. This research aims to evaluate the influence of rainwater harvesting in residential buildings on stormwater in a basin located in southern Brazil (Rio Cachoeira Basin). Urbanised and non-urbanised areas, soil types, curve numbers and time of concentration of each sub-basin were taken into account. Through the HEC-HMS programme, it was possible to calculate hydrographs for the base scenario (when there is no rainwater harvesting). Then, rainwater tanks for the residential buildings were sized using the computer programme Netuno. In the second scenario, there is rainwater harvesting in all residential buildings. Thus, the hydrographs for the second scenario were also calculated. The peak flow reduction potentials for the sub-basins ranged from 2.7% to 14.3%. The highest percentage (14.3%) did not occur in the sub-basin with the most extensive roof area; such highest peak flow reduction occurred in Bom Retiro sub-basin. In Bom Retiro sub-basin, there are more houses than multi-storey residential buildings. Even when considering the full potential of rainwater harvesting for roof areas of all existing buildings in the Rio Cachoeira Basin, the average potential reduction in peak flow was 7.2%. The conclusion is that rainwater tanks in residential buildings have little influence on stormwater runoff, and the stormwater runoff will be less affected when the area of the hydrographic basin is larger. Thus, the reduction in peak flows is insignificant when considering the flooding in the region.  
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  ISSN 0301-4797 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Custodio2023116814 Serial 231  
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Author Alexander, A.C.; Ndambuki, J.M. url  openurl
  Title (down) Impact of mine closure on groundwater resource: Experience from Westrand Basin-South Africa Type Journal Article
  Year 2023 Publication Physics and Chemistry of the Earth, Parts A/B/C Abbreviated Journal  
  Volume 131 Issue Pages 103432  
  Keywords Acid mine drainage, Groundwater quality, Mine closure, Spatio-temporal variation, Westrand Basin  
  Abstract The mining sector is at the edge of expanding to cater for natural resources that are much needed for technological development and manufacturing. Mushrooming of mines will consequently increase the number of mines closure. Moreover, mines closure have adverse impact on the environment at large and specifically on water resources. This study analyses historical groundwater quality parameters in mine intensive basin of Westrand Basin (WRB) to understand the status of groundwater quality in relation to mining activities and mine closure. Geographic information system (GIS) was used to map the spatio-temporal variation of groundwater quality in the basin and groundwater quality index (GQI) to evaluate its status. The coefficient of variation (CV) was applied to understand the stability of groundwater quality after the mine closure. Results indicated unstable and altered trend with increasing levels of acidity and salts concentration around the mines vicinity following the mine closure. The resultant maps indicated a significant deterioration of groundwater quality around the WRB with concentrations decreasing downstream. Obtained average GQI for the study period of 1996–2015 suggested a moderate groundwater quality at a range of GQI = 64–73. The CV indicated varying water quality at CV \textgreater 30% suggesting presence of source of contamination. Observed groundwater quality trends in Westrand basin suggested that mines closure present potential threat on groundwater quality and thus, a need for a robust mine closure plan and implementation.  
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  ISSN 1474-7065 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ alexander_impact_2023 Serial 134  
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Author Boulesteix, T.; Cathelineau, M.; Deloule, E.; Brouand, M.; Toubon, H.; Lach, P.; Fiet, N. url  openurl
  Title (down) Ilmenites and their alteration products, sinkholes for uranium and radium in roll-front deposits after the example of South Tortkuduk (Kazakhstan) Type Journal Article
  Year 2019 Publication Journal of Geochemical Exploration Abbreviated Journal  
  Volume 206 Issue Pages 106343  
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  Abstract The approximate determination of average Ra/U disequilibria in orebodies is one of the most common causes of errors in U reserve estimations. In roll-front deposits, the disequilibria are however frequently distributed following complex geometries, which must be fully understood to prevent major U reserve overestimates and costly unproductive extractive operations. The processes responsible for disruption of the radioactive equilibria and the U and Ra carriers in such complex natural systems remain poorly constrained. In this contribution, we propose an innovative approach, mixing orebody to sub-grain scale studies to unravel the distribution of U and Ra and the processes responsible for their concentration and uncoupling. Using mineral separations, gamma spectrometry and mineral-chemical analyses, we identified the Fe-Ti clusters (altered ilmenite + pyrite/marcasite) as the microsites for coffinite precipitation and Ra concentration. To understand the influence of such clusters on the distribution of U and Ra at the deposit scale, whole-rock Ra/U disequilibria were measured and mapped at a series of ten drill holes along a profile crosscutting the studied roll-front. The main Ra/U disequilibria are encountered around the mineralization in low U content zones. They are controlled by two main processes. (1) In the oxidized zones, the immobility of 230Th with respect to the U produces patches of Ra disequilibria (carried by the altered U minerals). (2) In the immediate vicinity of the roll-front, the dissolution of the mineralization produces an Ra flux trapped by the alteration products of ilmenites, as definitely confirmed by direct SIMS measurements. Such a process is responsible for the Ra disequilibria envelope located downstream of the richest ores, also known as Ra halo. The highest Ra/U ratios correspond to oxidized upstream samples, but most other high Ra/U ratios are from reduced downstream samples close to the mineralization. Such a low to medium U content envelope with high Ra/U ratios constitutes the main cause of U reserve overestimations.  
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  ISSN 0375-6742 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ boulesteix_ilmenites_2019 Serial 181  
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Author Ibrahim, A.S.; Zayed, I.S.A.; Abdelhaleem, F.S.; Afify, M.M.; Ahmed, A.; Abd-Elaty, I. url  openurl
  Title (down) Identifying cost-effective locations of storage dams for rainfall harvesting and flash flood mitigation in arid and semi-arid regions Type Journal Article
  Year 2023 Publication Journal of Hydrology: Regional Studies Abbreviated Journal  
  Volume 50 Issue Pages 101526  
  Keywords Flash flood, Morphometric parameters, GIS, Cost-effective, Wadi Tayyibah, Dams  
  Abstract Study region Wadi Tayyibah is located in south Sinai, Egypt, in a region called Abou Zenima, and it is used to develop this study. Study focus Flash floods tremendously impact many facets of human life due to their destructive consequences and the costs associated with mitigating efforts. This study aims to evaluate the harvesting of Runoff by delineating the watersheds using the Hydrologic Engineering Center-1 (HEC-1) model and ArcGIS software in trying to benefit from it in different ways. All morphometric parameters of the basin were considered, and the risk degree of the different sub-basins was determined. The suitable locations of dams were identified using a Geographical Information System (GIS) using the basin’s morphometric characteristics. New hydrological insights for the region The study proposed a total number of eight dams, including five dams that were recommended for sub-basin (1) and three dams in sub-basin (4), while sub-basins (2) and (3) are not suitable locations to build dams according to the contour map of Wadi Tayyibah. Results indicate that, based on the constructed flash flood hazard maps and the basin’s detailed morphometric characteristics, the best locations of dams are Dam (3) in sub-basin (1) and Dam (7) in sub-basin (4), where the runoff volume reached 3.13 million cubic meters (Mm3) and 5.56 Mm3 for return period 100, respectively. This study is useful for decision-makers and designers for using morphometric parameters and flash flood hazard degree maps to select dam locations. Also, the cost-benefit analysis for using the morphometric parameters is required to be investigated.  
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  ISSN 2214-5818 ISBN Medium  
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  Notes Approved no  
  Call Number THL @ christoph.kuells @ Ibrahim2023101526 Serial 238  
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Author Hubbard, B.E.; Gallegos, T.J.; Stengel, V.; Hoefen, T.M.; Kokaly, R.F.; Elliott, B. url  openurl
  Title (down) Hyperspectral (VNIR-SWIR) analysis of roll front uranium host rocks and industrial minerals from Karnes and Live Oak Counties, Texas Coastal Plain Type Journal Article
  Year 2024 Publication Journal of Geochemical Exploration Abbreviated Journal  
  Volume 257 Issue Pages 107370  
  Keywords Critical minerals, Hyperspectral, Industrial minerals, Mine waste, Texas coastal plain, Uranium  
  Abstract VNIR-SWIR (400–2500 nm) reflectance measurements were made on the surfaces of various cores, cuttings and sample splits of sedimentary rocks from the Tertiary Jackson Group, and Catahoula, Oakville and Goliad Formations. These rocks vary in composition and texture from mudstone and claystone to sandstone and are known host rocks for roll front uranium occurrences in Karnes and Live Oak Counties, Texas. Spectral reflectance profiles, 569 in total, were reduced to 125 representative spectral signatures, which were analyzed using the U.S. Geological Survey’s (USGS) Material Identification and Characterization Algorithm (MICA). MICA uses an automated continuum-removal procedure together with a least-squares linear regression to determine the fit of observed sample spectral absorption features to those of reference mineral standards in a spectral library. The reference minerals include various clay, mica, carbonate, ferric and ferrous iron minerals and their mixtures. In addition, absorption feature band-depth analysis was done to identify rock surfaces exhibiting absorption features related to uranium and zeolite minerals, which were not included in the command files used to execute MICA. Rocks from each of the four geologic units produced broadly similar spectral signatures as a result of comparable mineral compositions, but there were some notable differences. For example, Ca- and Na-montmorillonite was matched most frequently to the spectral absorption features in 2-μm (∼2000–2500 nm) wavelengths, while goethite occurred often at 1-μm (∼400–1000 nm) wavelengths. The latter is related to limonitic iron-staining in and around oxidized zones of the uranium roll front as described in previous papers. Rocks of the Jackson Group differed from those of the Catahoula, Oakville and Goliad units in that the former exhibited spectral features we interpret as being due to the presence of lignite-bearing mudstone layers. Goliad rocks exhibit spectral features related to dolomite, gypsum, anhydrite, and an unidentified green clay mineral that is possibly glauconite. Jackson Group rocks also exhibit weak but well-resolved absorption features at 964 and 1157 nm related to either or both zeolite minerals clinoptilolite and heulandite. These zeolite minerals and a few spectra exhibiting hydrous silica absorption features are indicative of alteration of volcanic glass in tuffaceous mudstone and claystone layers. A few sample spectra exhibited strong absorption features at around 1135 nm related to the uranium mineral coffinite. Both the 1135 nm coffinite and 1157 nm zeolite absorption features overlap somewhat, potentially making them difficult to distinguish without additional hyperspectral field, laboratory or remote sensing data. The results of this study were compared to mixtures of minerals described for ore, gangue and alteration minerals in deposit models for sandstone-hosted uranium, sedimentary bentonite and sedimentary zeolite. Use of these spectra can help facilitate mapping of both waste materials from the legacy mining of the above commodities, as well as future exploration and resource assessment activities.  
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  ISSN 0375-6742 ISBN Medium  
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  Call Number THL @ christoph.kuells @ hubbard_hyperspectral_2024 Serial 178  
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Author Androvitsanea, A.; Fawzy, M.; Fuchs, J.; Külls, C.; Fahlbusch, H.; Heiden, J. openurl 
  Title (down) Hydrologische Bedingungen im Heraion von Samos vom 12. bis 8. Jh. v. Chr. und ihre Bedeutung für die wasserbauliche Infrastruktur Type Journal Article
  Year 2018 Publication Environmental Water Engineering Abbreviated Journal  
  Volume 1 Issue 1 Pages 1-21  
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  Call Number THL @ christoph.kuells @ Androvitsanea2018hydrologische Serial 17  
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