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Tan, K., Li, C., Liu, J., Qu, H., Xia, L., Hu, Y., et al. (2014). A novel method using a complex surfactant for in-situ leaching of low permeable sandstone uranium deposits. Hydrometallurgy, 150, 99–106.
Abstract: Applications of a complex surfactant developed in-house to in-situ leaching of low permeable sandstone uranium deposits are described based on results from agitation leaching, column leaching, resin adsorption, and elution experiments using uranium containing solution from the in-situ leaching site. The results of agitation leaching experiments show that adding surfactant with different concentrations into leaching solution improves the leaching rate of uranium. The maximum leaching rate of uranium from agitation leaching reached 92.6% at an added surfactant concentration of 10mg/l. Result of column leaching experiment shows that adding surfactant with varying concentrations into leaching solutions increased the permeability coefficient of ore-bearing layer by 42.7–86.8%. The leaching rate of uranium from column leaching increased by 58.0% and reached 85.8%. The result of kinetic analysis shows that for the extraction of uranium controlled by diffusion without surfactant the apparent rate constant 0.0023/d changed to 0.0077/d for the extraction with surfactant controlled by both diffusion and surface chemical reactions. Results from resin adsorption and elution experiments show that there was no influence on resin adsorption and elution of uranium with an addition of 50mg/l surfactant to production solution from in-situ leaching. The adsorption curve, sorption capacity of resin, recycling of resin remained the same as without adding any surfactant. Introducing complex surfactant to leaching solution increased the peak concentration of uranium in eluents, reduced the residual uranium content in resin, and promoted the elution efficiency. The method of using a complex surfactant for in-situ leaching is useful for low permeable sandstone uranium deposits.
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Demuth, S., & Külls, C. (1997). Probability analysis and regional aspects of droughts in southern Germany. Sustainability of Water Resources under Increasing Uncertainty, (240), 97.
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Pereira, A. J. S. C., & Neves, L. J. P. F. (2012). Estimation of the radiological background and dose assessment in areas with naturally occurring uranium geochemical anomalies—a case study in the Iberian Massif (Central Portugal). Journal of Environmental Radioactivity, 112, 96–107.
Abstract: Naturally occurring uranium geochemical anomalies, representative of the several thousand recognized in the Portuguese section of the Iberian Massif and outcropping in three target areas with a total of a few thousand square metres, were subjected to a detailed study (1:1000 scale) to evaluate the radiological health-risk on the basis of a dose assessment. To reach this goal some radioactive isotopes from the uranium, thorium and potassium radioactive series were measured in 52 samples taken from different environmental compartments: soils, stream sediments, water, foodstuff (vegetables) and air; external radiation was also measured through a square grid of 10×10m, with a total of 336 measurements. The results show that some radioisotopes have high activities in all the environmental compartments as well as a large variability, namely for those of the uranium decay chain, which is a common situation in the regional geological setting. Isotopic disequilibrium is also common and led to an enrichment of several isotopes in the different pathways, as is the case of 226Ra; maximum values of 1.76BqL−1 (water), 986Bqkg−1 (soils) and 18.9Bqkg−1 (in a turnip sample) were measured. On the basis of a realistic scenario combined with the experimental data, the effective dose from exposure to ionizing radiation for two groups of the population (rural and urban) was calculated; the effective dose is variable between 8.0 and 9.5mSvyear−1, which is 3–4 times higher than the world average. Thus, the radiological health-risk for these populations could be significant and the studied uranium anomalies must be taken into account in the assessment of the geochemical background. The estimated effective dose can also be used as typical of the background of the Beiras uranium metalogenetic province and therefore as a “benchmark” in the remediation of the old uranium mining sites.
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Akter, A., Tanim, A. H., & Islam, M. K. (2020). Possibilities of urban flood reduction through distributed-scale rainwater harvesting. Water Science and Engineering, 13(2), 95–105.
Abstract: Urban flooding in Chittagong City usually occurs during the monsoon season and a rainwater harvesting (RWH) system can be used as a remedial measure. This study examines the feasibility of rain barrel RWH system at a distributed scale within an urbanized area located in the northwestern part of Chittagong City that experiences flash flooding on a regular basis. For flood modeling, the storm water management model (SWMM) was employed with rain barrel low-impact development (LID) as a flood reduction measure. The Hydrologic Engineering Center’s River Analysis System (HEC-RAS) inundation model was coupled with SWMM to observe the detailed and spatial extent of flood reduction. Compared to SWMM simulated floods, the simulated inundation depth using remote sensing data and the HEC-RAS showed a reasonable match, i.e., the correlation coefficients were found to be 0.70 and 0.98, respectively. Finally, using LID, i.e., RWH, a reduction of 28.66% could be achieved for reducing flood extent. Moreover, the study showed that 10%–60% imperviousness of the subcatchment area can yield a monthly RWH potential of 0.04–0.45 m3 from a square meter of rooftop area. The model can be used for necessary decision making for flood reduction and to establish a distributed RWH system in the study area.
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Carrión, A., & Fornes, A. (2016). Underground medieval water distribution network in a Spanish town. Tunnelling and Underground Space Technology, 51, 90–97.
Abstract: The city of Alcudia de Crespins, in the centre of the Valencia province (east of Spain), has an exceptional water distribution system that in the past served fresh water to many houses in the town. This system is formed by more than one km of tunnels and underground cisterns, and dates probably in the late medieval times, while it has been in use and suffering modifications until 1955. This paper presents the structure and characteristics of such exceptional system, and explains the functioning parameters of the infrastructure.
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Chen, Y., Hong, Y., Huang, D., Dai, X., Zhang, M., Liu, Y., et al. (2022). Risk assessment management and emergency plan for uranium tailings pond. Journal of Radiation Research and Applied Sciences, 15(3), 83–90.
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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Rajfur, M., Kłos, A., & Wacławek, M. (2010). Sorption properties of algae Spirogyra sp. and their use for determination of heavy metal ions concentrations in surface water. Bioelectrochemistry, 80(1), 81–86.
Abstract: Kinetics of heavy-metal ions sorption by alga Spirogyra sp. was evaluated experimentally in the laboratory, using both the static and the dynamic approach. The metal ions – Mn2+, Cu2+, Zn2+ and Cd2+ – were sorbed from aqueous solutions of their salts. The static experiments showed that the sorption equilibria were attained in 30min, with 90-95% of metal ions sorbed in first 10min of each process. The sorption equilibria were approximated with the Langmuir isotherm model. The algae sorbed each heavy metal ions proportionally to the amount of this metal ions in solution. The experiments confirmed that after 30min of exposition to contaminated water, the concentration of heavy metal ions in the algae, which initially contained small amounts of these metal ions, increased proportionally to the concentration of metal ions in solution. The presented results can be used for elaboration of a method for classification of surface waters that complies with the legal regulations.
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Külls, C. (2011). Rekonstruktion hydrologischer Extreme in der Namibwüste. Berichte der naturforschenden Gesellschaft zu Freiburg im Breisgau, (101), 69–81.
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Shams, A. (2014). A rediscovered-new ‘Qanat’ system in the High Mountains of Sinai Peninsula, with Levantine reflections. Journal of Arid Environments, 110, 69–74.
Abstract: Since the Achaemenid Empire in 532–332 BCE, the ‘Qanat’ became the central irrigation system in the arid and semi-arid lands. Several terms are used for ‘Qanat’ in different regions, including the Karez, Qanat, Falaj type Daudi, Qanat Romani, Fuqara (Foggara), or Khettara as known in Central Asia, Persia, Southeast Arabia, Levant, North Africa, or Morocco respectively. Typically, the ground, spring or surface water (i.e. seasonal floods or river-fed) sources feed similar irrigation system. Based on thirteen years of extensive survey and analysis work (i.e. Sinai Peninsula Research 2000–2013 CE), this paper presents a rediscovered-new Qanat system in the High Mountains of Sinai Peninsula (i.e. UNESCO World Heritage Site ‘WHS’ no. 954) under chronological open question with Levantine reflections. In 1970s CE, the present Sinaitic site of Farsh Abu A’lwan or the anciently known Farsh Shamma’a was archaeologically surveyed without a direct reference to the Qanat system in-situ. Scientifically, it is an argumentative and unique Qanat system in terms of chronology, location (region), site (local-setting), water source, size and household utility. It is the only discovered ‘Qanat’ across the Sinai, connecting the Near East and North Africa.
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Külls, C., & Schwarz, O. (2000). Grundwasseranreicherung in den Waldbeständen der Teninger Allmend bei Freiburg im Breisgau. In Beiträge zur Physischen Geographie (pp. 67–78). Frankfurt am Main: Werner-F. Bär.
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