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This article discusses the mineral specimen known as samsonite, which is highly valued by collectors. Samsonite is a rare mineral composed of silver, manganese, and sulfur, and it was discovered in the St. Andreasberg mining district in Germany. The article provides information about the physical characteristics of samsonite and its historical significance. It also describes the acquisition process of a samsonite specimen by the Smithsonian Institution. Overall, the article offers valuable insights into the world of mineral collecting and the importance of samsonite as a prized mineral specimen. [Extracted from the article]

A radiological assessment of inland freshwater fishes of wetland haor zones, near a uranium mine and Rooppur Nuclear Power Plant (RNPP) areas, was performed. Gamma spectrometric analysis showed the accumulation of 226Ra, 228Ra, and 40K in all studied fishes, with varying degree levels of concentrations. The average radioactivity levels of 226Ra, 228Ra and 40K in haor fish samples ranged from 2.76 ± 1.51 to 22.02 ± 3.81 Bq kg−1, 1.78 ± 0.69 to 21.53 ± 1.40 Bq kg−1 and 405.51 ± 22.04 to 749.80 ± 42.65 Bq kg−1, respectively. Conversely, the respective values for Bata fish samples of Rooppur Nuclear power plant sites varied from 2.66 ± 0.80 to 6.62 ± 0.81 Bq kg−1, 2.31 ± 0.62 to 5.18 ± 49.81 Bq kg−1 and 342.00 ± 4.98 to 461.45 ± 18.00 Bq kg−1, respectively. Activity levels of Taki fish (Channa punctatus) from haors zones were almost 3–4 times higher than the Meni fish (Nundus nundus) of the same locations and Bata fish (Labeo bata) of the RNPP site. The general public may attain doses of 244.54 µSv from the consumption of haor fish and 84.02 µSv from the fish of the RNPP sites yearly. The chance of an increase in cancer risk from intake of haor fish was higher than the ICRP values of 2.9 × 10−4. Univariate statistics showed that 226Ra and 228Ra radionuclides do not normally distribute, whereas 40K is normally distributed in the studied fish species. Multivariate statistical analysis demonstrated that the radioactivity and estimated radiological parameters are strongly positively correlated with 226Ra and 228Ra, and also positively correlated with 40K. Hence, it indicated that the contents in the freshwater fish species are usually controlled and influenced by similar geogenic sources and occur together. It is presumed that the radiological risk is mostly associated with and dominated by the uranium and thorium series and non-series 40K radionuclides in the freshwater fish species. [ABSTRACT FROM AUTHOR]

Civilian and military nuclear programs of several nations over more than 70 years have led to significant quantities of heterogenous solid, organic, and aqueous radioactive wastes bearing actinides, fission products, and activation products. While many physicochemical treatments have been developed to remediate, decontaminate and reduce waste volumes, they can involve high costs (energy input, expensive sorbants, ion exchange resins, chemical reducing/precipitation agents) or can lead to further secondary waste forms. Microorganisms can directly influence radionuclide solubility, via sorption, accumulation, precipitation, redox, and volatilization pathways, thus offering a more sustainable approach to remediation or effluent treatments. Much work to date has focused on fundamentals or laboratory-scale remediation trials, but there is a paucity of information toward field-scale bioremediation and, to a lesser extent, toward biological liquid effluent treatments. From the few biostimulation studies that have been conducted at legacy weapon production/test sites and uranium mining and milling sites, some marked success via bioreduction and biomineralisation has been observed. However, rebounding of radionuclide mobility from (a)biotic scale-up factors are often encountered. Radionuclide, heavy metal, co-contaminant, and/or matrix effects provide more challenging conditions than traditional industrial wastewater systems, thus innovative solutions via indirect interactions with stable element biogeochemical cycles, natural or engineered cultures or communities of metal and irradiation tolerant strains and reactor design inspirations from existing metal wastewater technologies, are required. This review encompasses the current state of the art in radionuclide biogeochemistry fundamentals and bioremediation and establishes links toward transitioning these concepts toward future radioactive effluent treatments. [ABSTRACT FROM AUTHOR]

Magmatic rocks host different types of uranium deposits that can range from magmatic/high-temperature hydrothermal systems to post-magmatic, low-temperature hydrothermal deposits. The uranium mineralization in the syn- or late-magmatic systems could be divided into three types. (1) Magmatic deposits related to differentiated peralkaline complexes that are typically rich in SiO2 (>72 wt%) and poor in (B: Fe+Mg+Ti)<100 (in cation values). The Na/K ratio in these rocks is > 1 and they have high contents of incompatible lithophile elements such as Nb, Ta, Zr, REE, Th and U. (2) Magmatic deposits related to strongly peraluminous magmas, derived from partial melting of crust. They are the result of a low degree partial melting of crustal arkosic (quartz-feldspathic) rocks with high SiO2 (>74 wt%), low B < 40 and positive values for (A: Al-[Na+K + 2Ca]) (in cation values)), and are mostly accompanied by Li and F minerals. (3) Magmatic deposits related to the evolved hot peralkaline or metaluminous (A [A2] - to I- types) magma that assimilated fertile materials of the crust and endured a high rate of crystal fractionation. They mostly form high-temperature (vein-type and hybrid system) deposits. The rate of fluid in magma is important for the formation of this type of deposit. Therefore, the fertile magmas for this type of deposits typically have SiO2 >72 wt%, positive values of A, B < 50 and K/Rb < 150. They are possibly rich in Mo and F. Dry-hot alkaline felsic volcanic rocks are more suitable for post-magmatic low-temperature hydrothermal deposits. The altered intrusive rocks with about 200 Ma age and higher contents of refractory minerals, are suitable candidates for supporting the post-magmatic, low-temperature hydrothermal uranium mineralization. [ABSTRACT FROM AUTHOR]

The Jurassic Zhiluo Formation in the western Ordos Basin is known for hosting economically significant sandstone-type uranium deposits. However, the understanding of sediment sources for this formation, crucial for guiding uranium exploration, has been a subject of controversy. This study aims to address this issue by presenting a systematic dataset derived from detrital zircons found in the uranium-bearing sandstones of the Zhiluo Formation. The dataset includes U‒Pb dating, trace element analyses, and in-situ Hf isotope compositions. The detrital zircons analysed are predominantly of magmatic origin, as indicated by a Th/U ratio greater than 0.4. Their U‒Pb ages can be broadly categorized into a predominant population ranging from 170 to 500 Ma, with a peak ca. 300 Ma. Additionally, there are two minor age populations: 1600–2050 Ma (peaking at ca. 1850 Ma) and 2300–2650 Ma (peaking at ca. 2500 Ma). The εHf(t) values of these zircons exhibit a range from −27 to 7, concentrating mostly from −16 to 5. Importantly, none of them aligns above the deficit mantle evolutionary line in an εHf(t) vs. age covariant diagram. A comprehensive comparison of the analytical U‒Pb ages and Hf isotopic results with previously reported data from adjacent geological units surrounding the western Ordos Basin suggests that the primary provenance supply area for the sandstones is the Alxa Block, particularly the uranium-rich felsic rocks within it. Minor contributions are inferred from the Yinshan Block and the Qilian Orogenic Belt. The northwestern region of the study appears to be the primary prospect area for uranium exploration, and we have proposed effective measures to refine the exploration target area and enhance exploration efficiency. Overall, the study provided crucial insights into deducing provenance supply areas and transport paths, with implications for uranium exploration in sedimentary basins worldwide. [ABSTRACT FROM AUTHOR]

The new coronavirus pandemic (2019-nCoV) arrived in Brazil in February 2020, where the worsening led to social isolation. The population started to remain entirely in their homes, mainly the elderly, children, and adolescents. The study aimed to determine the impact of radioecological dosimetry within the residences located in the municipality from Espinharas, Paraíba, Brazil, where one of the main uranium deposits in Brazil occurs. A scintillator-type gamma spectrometer with a combined NaI (Tl) and BGO probe, at 1.0 m from the soil surface, was used. A total occupation factor for the pandemic period was considered. The dose-response for the three months ranged from 0.55 to 1.70 mSv, with an average of 0.68 mSv, which characterises an increase of 25% when compared to the same period of the retrospective study in 2014. In the period of one year, the dosimetric response can vary between 2.22 and 6.80 mSv/y, with an average of 2.73 mSv/y. The work portrays the importance of a database for future affirmative actions and the determination of different radiometric conditions in an environment already considered to have a high level of natural radioactivity. The study also provides definitions of extreme exposure conditions and correlations with public health parameters. [ABSTRACT FROM AUTHOR]

Groundwater supplied by Beberibe aquifer, the main source for the metropolitan region north of Recife, Brazil, exhibits radioactivity because of the presence of uranium resulting from the alteration of phosphate rocks that occur at the base of the Gramame formation, which is superimposed on the aquifer. Using geochemical modelling as a tool to characterise hydrodynamic systems, studies were performed assessing uranyl ions and their interaction with other chemical and mineralogical species found in the aquifer. The results of the geochemical modelling made it possible to perform studies of uranium mobility in the aquifer, analysing the alteration of phosphate minerals and revealing the occurrence of different chemical species. This model suggests that the species present in the aquifer were available for the trophic chain and capable of affecting human health in a differentiated way. [ABSTRACT FROM AUTHOR]

The natural radioactivity data revealed that eU reached up to 157.4, 1625 and 178 ppm in microgranite and dolerite dikes as well as japer vein, respectively, whereas the two-mica granite possesses the higher eTh-contents up to 53.8 ppm. Mineralogically, the two-mica granite is enriched in thorite, brockite and uranothorite, whereas uraninite and coffinite are recorded in dolerite, and the latter one is recorded in microgranite, bostonite and jasper. Primary uranium minerals as uraninite and coffinite could be a source for uranium enrichment and the formation of secondary uranium mineralisation. Uranium mobilisation was active towards the two perpendicular shear zones having NNW-SSE and ENE-WSW rejuvenated trends. Successive hydrothermal alterations play their role in the formation of uranium ore deposits to be trapped in post-granitic dikes. [ABSTRACT FROM AUTHOR]

In many ways, vanadium is what makes volborthite interesting, appropriately so for this contribution because vanadium's history is deeply rooted in Mexico. Vanadium is much more reactive in the presence of oxygen with no fewer than 264 described oxide species; 37 of these contain copper and 21 include uranium, the elements with which vanadium species are most commonly found - notably sengerite [Cu SB 2 sb (UO SB 2 sb ) SB 2 sb (VO SB 4 sb ) SB 2 sb -6H SB 2 sb O] is the only species that includes all three. Volborthite dominantly occurs in sediment-hosted vanadium-uranium oxide deposits, exemplified by the "roll-front" deposits of the Four Corners region in the American Southwest. These include native vanadium, simple vanadium sulfides, vanadium-copper sulfides, and complex vanadium-copper (plus As, Ge, Mo, Pb, Mo) sulfosalts. [Extracted from the article]

The present study is an application of a radiochemical procedure for the determination of 238U, 235U and 234U as well as uranium isotopic ratios in El Sela ore grade samples that located at the Southeastern Desert of Egypt. This procedure is consisting of several steps include sample preparation, chemical separation and source preparation followed by counting using alpha-particle spectrometry technique. Radiochemical determination of various uranium isotopes contents indicated that El Sela uranium deposits are considered as a recent deposit where there was a large difference between radiochemically and radiometrically determined uranium. The measured 234U/238U activity ratios for most samples were approximately unity, indicating that secular radioactive equilibrium was established between 238U and 234U in the El Sela mineralised rocks. On the other hand, 238U and 234U might be equally leached due to the effect of rock-water interactions during the pluvial time by the action of surficial or underground water. The 238U/235U activity ratios of the studied mineralised granites were significantly shifted from the natural ratio 21.7, indicating that the redox conditions and alteration processes played an important role in the fractionation of 238U from 235U. The values of 234U/235U ratios in the studied granites varied between 23.08 and 34.70 in different samples, suggesting 235U migration out due to the prevailing conditions. [ABSTRACT FROM AUTHOR]

Characterizing the diverse, root-associated fungi in mine wastes can accelerate the development of bioremediation strategies to stabilize heavy metals. Ascomycota fungi are well known for their mutualistic associations with plant roots and, separately, for roles in the accumulation of toxic compounds from the environment, such as heavy metals. We sampled soils and cultured root-associated fungi from blue grama grass (Bouteloua gracilis) collected from lands with a history of uranium (U) mining and contrasted against communities in nearby, off-mine sites. Plant root-associated fungal communities from mine sites were lower in taxonomic richness and diversity than root fungi from paired, off-mine sites. We assessed potential functional consequences of unique mine-associated soil microbial communities using plant bioassays, which revealed that plants grown in mine soils in the greenhouse had significantly lower germination, survival, and less total biomass than plants grown in off-mine soils but did not alter allocation patterns to roots versus shoots. We identified candidate culturable root-associated Ascomycota taxa for bioremediation and increased understanding of the biological impacts of heavy metals on microbial communities and plant growth. [ABSTRACT FROM AUTHOR]

Personal exposure studies suffer from uncertainty issues, largely stemming from individual behaviour uncertainties. Built on spatial-temporal exposure analysis and methods, this study proposed a novel approach to spatial-temporal modelling that incorporated behaviour classifications taking into account uncertainties, to estimate individual livestock exposure potential. The new approach was applied in a community-based research project with a Tribal community in the southwest United States to address questions on potential livestock exposure to abandoned uranium mines (AUMs). The study aimed to 1) classify Global Positioning System (GPS) data from livestock into three behaviour subgroups – grazing, travelling or resting; 2) calculate the daily cumulative exposure potential for livestock; 3) assess the performance of the computational method with and without behaviour classifications. Using Lotek Litetrack GPS collars, we collected data at a 20-min-interval for two flocks of sheep and goats during the spring and summer of 2019. Analysis and modelling of GPS data demonstrated no significant difference in individual cumulative exposure potential within each flock when animal behaviours with probability/uncertainties were considered. However, when daily cumulative exposure potential was calculated without consideration of animal behaviour or probability/uncertainties, significant differences among animals within a herd were observed, which does not match animal grazing behaviours reported by livestock owners. These results suggest that the proposed method including behaviour subgroups with probability/uncertainties more closely resembled the observed grazing behaviours. Results from the research may be used for future intervention and policy-making on remediation efforts in communities where grazing livestock may encounter environmental contaminants. [ABSTRACT FROM AUTHOR]

As the scale of nuclear power in China continues to expand, the problem of external dependence on uranium resources has become more and more prominent. The guarantee of uranium resources is facing great risks, especially the procurement risks. Therefore, the procurement risks of uranium resources based on the analytic hierarchy process and fuzzy comprehensive assessment method from multiple perspectives is analyzed in this paper. The results show that the risk values of target region selection, supplier selection and uranium mining are 73.6, 71.3 and 71.8 respectively, which are the main risks. The risk values of procurement contract and procurement cost are 69.3 and 67.5, which are relatively low. They can be regarded as the secondary risks. In addition, the countermeasures of uranium resource procurement risk are put forward from six aspects including risk mitigation, risk prevention, risk transfer, risk avoidance, risk retention and risk backup measures. It is helpful to guide the risk management of China's uranium resources in procurement and transportation activities [ABSTRACT FROM AUTHOR]

The contemporary artist Bonnie Devine (b 1952), a member of the Serpent River First Nation in Ontario, Canada, works in a wide range of media to address the cultural and environmental consequences of uranium mining that occurred in her community. Uranium extraction in the area has resulted in numerous devastations, including radioactive contamination of all fifty-five miles of the Serpent River. In this study, I use ecocritical methodologies to examine how local environmental conditions, Anishinaabe cosmologies, and histories of Cold War resource extraction inform Devine's animated film Rooster Rock: The Story of Serpent River (2002). The work demonstrates her intensive investigation of the unique properties of uranium, its effect on place, beings and ontologies, and the ways Ontarian uranium mining dovetails with the artist's personal history. Additionally, this article calls attention to divergent and overlapping modes of knowledge and valuation practiced by Indigenous and Euro-American participants in this history. [ABSTRACT FROM AUTHOR]

The study investigates the spatio-temporal variability of radon ( 222Rn) with respect to the geology and hydrogeology of the Vamanapuram River Basin (VRB), SW India. A total of 40 groundwater samples were collected during three seasons of 2019. RAD7, RAD-H2O accessory (Durridge Co. USA) was used to analyse 222Rn, and physico-chemical parameters were measured in situ by Horiba Laqua water quality analyser. The results show that the 222Rn activity was in the range of 640–79,940 Bq/m³ in pre-monsoon, 250–36,950 Bq/m3 in monsoon and 420–59,790 Bq/m³ in post-monsoon season and 18% of samples exceeded the permissible limit of USEPA (11,000 Bq/m³ ) during all seasons. Remarkably, the samples exceeding the permissible limit of 222Rn were associated with khondalitic rocks with notable amount of uranium-bearing minerals and NW-SE trending lineaments, the most active type of lineament in the study area. The study shows the considerable influence of seasons and the highest activities were found during pre-monsoon compared to the other two seasons. [ABSTRACT FROM AUTHOR]

Wadi El Reddah (valley), Central Eastern Desert, Egypt extends in North-South direction, it represents a semi-closed basin with only one outlet in its northern tip. Wadi El Reddah is mainly surrounded by scattered exposures in a sequence of metagabbro-diorite and metavolcanics complex in addition to wide sector of Hammamat sedimentary rocks, monzongranites of Gabal El Reddah, perthitic leucogranites of Gabal Gattar as well as swarms of post-granitic dykes. The studied sediments showed wide variation in their Uranium, Thorium, Radium (eU) and potassium (K%) contents. Uranium ranges from 5 to 51 ppm, with an average of 17.33 ppm, Th contents between 16 and 141 ppm, with 32.47 ppm as an average. Ra (eU) varies between 5 and 26 ppm with an average of 9.56 ppm. While potassium falls between 2.19% and 4.41% with an average of 3.19%. The disequilibrium conditions in the stream sediments under investigation indicated that they are mostly recent which is due to the fact that most of the radiometric measurements are lower than the chemical measurements. eTh/eU ratio values of old uranium deposits in the studied sediments suggested mineralisation in an environment of rapid deposition of rock detritus and poor weathering with the dominance of detrital radioactive minerals like thorite, samarskite, euxenite and xenotime. [ABSTRACT FROM AUTHOR]

This article examines conceptualisations of security in the debate over uranium mining and export in Fraser's Australia. Drawing together archives from the Fraser government, the Movement Against Uranium Mining, and newspaper coverage, the article demonstrates that pro- and anti-uranium groups held conflicting visions of (in)security: Fraser saw the exploitation of natural resources as an opportunity to strengthen Australia's geopolitical influence, while anti-uranium activists feared the risks that mining and export posed to the environment, Indigenous communities, public health and the survival of the planet. Tracing these competing visions of security through key developments in the nuclear debate in Australia, the article demonstrates that Fraser maintained his uranium policy by avoiding the security concerns of the anti-uranium movement. Nonetheless, the debate marked an early shift in the broader reformulation of narrow ideas of 'national security' to more expansive understandings of the term. [ABSTRACT FROM AUTHOR]

Uranium (U) is difficult to be transported from roots to leaves, but it has been reported to inhabit photosynthesis in leaves, so how does this work? In the present study, the effects of U (0–25 μM) on the development and photosynthesis in V. faba seedlings were studied under hydroponics. The results showed that U significantly inhibited the growth and development of V. faba plants, including decreased biomass, water content, lateral root number and root activity. U also led to a large accumulation of reactive oxygen species (ROS) in the leaves which affects leaf structural traits (e.g., decreased leaf area and chlorophyll a content). When U concentration was 25 μM, the net photosynthetic rate (Pn) and transpiration rate (Tr) were inhibited, which were only 66.53% and 41.89% of the control, respectively. Further analysis showed that the stomatal density of leaves increased with the increase of U concentration, while the stomatal aperture and stomatal conductance (Gs) were on the contrary. The results of chlorophyll fluorescence showed that the non-photochemical quenching coefficient (NPQ) increased and the electron transfer rate (ETR) decreased after U exposure, but fortunately, photosystem II (PSII) suffered little damage overall. In conclusion, the accumulation of U in the roots inhibited the root activity, resulting in water shortage in the plants. To prevent water loss, leaves have to regulated stomatal closure at the cost of weakening photosynthesis. These results provide a new insight into the mechanism by which U affects plant photosynthesis. [ABSTRACT FROM AUTHOR]

Radium is the most common source of alpha radiation exposure to humans and non-human species in the environment but the dosimetry is complicated by the decay chain which involves gamma exposure due to radon daughters. This paper seeks to determine the separate contributions of alpha and gamma doses to the total dose and total direct and non-targeted effect in a fish and a human cell line. This study aimed to isolate the effect of alpha particles following exposure to low doses of radium in cells, and their progeny which received no further exposure. This was initially done by comparing the survival values of a human keratinocyte cell line (HaCaT) and an embryonic Chinook salmon cell line (CHSE-214) exposed to gamma radiation, from survival of the same cell lines exposed to mixed alpha and gamma radiation through exposure to Ra-226 and its decay products. A Monte Carlo simulation was later performed to determine the contributions of radium decay products including radon daughters. The human cell line showed increased radioresistance when exposed to low doses of alpha particles. In contrast the fish cell line, which demonstrated radioresistance to low dose gamma radiation, showed increased lethality when exposed to low doses of alpha particles. Significant and complex levels of non-targeted effects were induced in progeny of irradiated cells. The simulation showed that gamma and beta decay products did not contribute significant dose and the highest beta dose was below the threshold for inducing non-targeted effects. The results confirm the need to consider the dose-response relationship when developing radiation weighting factors for low dose exposures, as well as the need to be aware of possible cell line and species differences. [ABSTRACT FROM AUTHOR]

Radon-222 contributes to half of the natural radiation exposure of humans and is one of the main causes of lung cancer. Of particular importance for humans is the exposure to radon-222 indoors, which enters living and working areas from the soil air, e.g. through cracks in the foundations of buildings. An easy and efficient way to minimise indoor radon in dwellings can be achieved through ventilation. How meteorological parameters and the geological background can influence ventilation efficiency in reducing indoor radon has not yet been fully investigated. Therefore, a decentralised ventilation system was installed in an unoccupied flat located in a former uranium mining region to analyse the effect of already existing ventilation modes on indoor radon activity concentration. It is aimed to assess 22 different ventilation experiments that were performed within the time period of one year. Even with a strong seasonal trend with significantly lower indoor radon activity concentrations in summer compared to winter, the decentralised ventilation system was able to reduce indoor radon by up to 83 %. Thereby, strong dependencies on the experimental parameters such as ventilation type or performance level of the fans were found. [ABSTRACT FROM AUTHOR]

Nine samples were chemically characterized and radiometrically analyzed for determination of 234U, 238U, 235U, 230Th, 232Th, 226Ra and 40K by γ-ray spectrometer Hyper Purity Germanium (HPGe detector). 238U activity concentrations reach up to 79.78 Bq Kg-1in the altered granites, 1714.11 and 2223.48 Bq Kg-1in the episyenite and pegmatite. Average 234U activity concentrations in the altered granite is 59.26 Bq Kg-1, between 175.88-543.47 Bq Kg-1and 48.19-1102.88 Bq Kg-1in the episyenite and pegmatite, respectively. 232Th activity concentrations vary between 14.16-1024.8 Bq Kg-1in the episyenite, 11.46-240.27 in the pegmatite and reach up to 201.45 Bq Kg-1in the altered granites. 40K activity concentrations range between 4.42-9.15, 2.76-7.34 and 2.68-9.94 Bq Kg-1in the altered granite, episyenite and pegmatite, respectively. 235U activity concentration ranges between 3.74–2.56, 12.45-78.86 and 0.58-102.34 Bq Kg-1 in the altered granite, episyenite and pegmatite, respectively. The studied altered granite, episyenite and pegmatite samples have relatively higher values than recorded in the international standards with the exception of potassium which has lesser amounts. It is demonstrated that pH changes, oxidation-reduction conditions, mineralogical constituents, in addition to alteration processes in these variable granitic environments were the main factors controlling uranium mobilization according to valid processes. The difference in alteration processes and La/Y ratio clarified the presence of more than one event of uranium accumulation and/or leaching in these rocks as confirmed by the presence of uranium accumulation and uranium vacant occurrences. Also, the isotopic ratios of uranium as 238U/235U,234U/235U, 234U/ 238U, 226Ra/ 238U,226Ra/ 230Th, 210Pb/ 226Ra, 230Th/ 238U, 230Th/ 234U with major, trace and rare earth elements were also affected by physico-chemical conditions changes. The present study shows that the samples of episyenite and pegmatite have been affected by leaching-accumulation events in the period from (1 × 105 to ˃2 × 105years). [ABSTRACT FROM AUTHOR]

This research explores contestations surrounding the rehabilitation of the Ranger Uranium Mine in the Northern Territory of Australia. I highlight how particular scientific knowledges are privileged throughout the rehabilitation process, but only so long as the rehabilitation problems at hand are deemed manageable. I also argue that the implications of the immense time scales of impacts are being ignored, and the question of monitoring, remediation, and regulation thousands of years into the deep future constitutes a kind of 'uncomfortable knowledge'. Ultimately, I contend that the legacy of the rehabilitated Ranger uranium mine will pose long-term threats to the environment and Mirarr Traditional Owners of the area, and that this slow violence constitutes a kind of unacknowledged environmental disaster, but one which is being disregarded through the active production of ignorance. [ABSTRACT FROM AUTHOR]

During the Second World War, Canada made several important contributions to wartime nuclear research efforts. The three main contributions were: establishing a domestic nuclear research laboratory in Montreal to investigate heavy water reactor; creating supply chains to provide uranium oxide, heavy water, and polonium to the Manhattan Project; and the direct contributions of several Canadians living in the United States to the project. These wartime efforts helped establish a legacy of nuclear research in Canada that has persisted to the present day. [ABSTRACT FROM AUTHOR]

The Taunsa uranium mineralisation is hosted by the upper Miocene–Pliocene Litra Formation, part of the molasse sediments (Siwalik Group) deposited in the Himalayan foreland basin of the eastern Sulaiman Range, Dera Ghazi Khan, Pakistan. The Litra Formation is the only rock unit hosting economic-grade uranium occurrences in the stratigraphic record of Pakistan. Surface radioactivity is mainly associated with cemented layers of the host sandstone, known as hard-bands, whereas weakly cemented sandstone is non-radioactive. The outcropping sandstone is dominantly whitish grey owing to bleaching, which is probably related to hydrocarbon migration from the underlying marine black shales. The main sandstone-type uranium mineralisation is phreatic owing to its parallelism with the water-table, whereas the concordantly oriented tabular (roll-type) ore is subordinate. The host sandstone layers have high dips ranging from 70 to 85°E indicating a deformed geological setting that makes the Taunsa uranium ore unique. Uranium is trapped mostly by scant organic matter, probably related to hydrocarbons, and also by Fe–Ti-oxide phases, phyllosilicates (chlorite and biotite), graphitic schist and black shale clasts in the host sandstone. Uranium ore minerals are mainly coffinite, pitchblende and minor brannerite. Uranium in the ore phases is accompanied by the high contents of Ca, Fe, Ti, Si and Al. Radiometric disequilibrium in the phreatic ore is strongly positive, whereas that in the tabular (roll-front) is moderately positive, which in turn suggests the former is younger than the latter. The coexistence of the two ore-types, characterised by different intensities of radiometric disequilibrium within the same uranium deposit, suggests that the phreatic uranium ore has possibly resulted from remobilisation of the tectonically uplifted tabular (roll-type) ore and its reprecipitation at the horizontally oriented redox interface following the water-table in the host sandstone aquifers. The Taunsa uranium resource is dominantly phreatic that has resulted from oxidation and remobilisation of the earlier tabular (roll-type) mineralisation. The phreatic uranium mineralisation is very young, which is indicated by low radioactivity and high positive disequilibrium in comparison with that within the tabular (roll-type) ore. Uranium phases are mainly pitchblende, coffinite and brannerite, associated with organic matter of hydrocarbon origin, with phyllosilicates and Fe–Ti-oxide phases. Outcrop of the host sandstone in the Taunsa area is pervasively bleached and is marked by flat topography. [ABSTRACT FROM AUTHOR]

More than 900 abandoned uranium mines litter the Navajo Nation, the poisonous legacy of the mid- to late-twentieth century uranium boom in the American West. This article discusses findings from recent archaeological work related to reclamation activities at a series of abandoned uranium mines in the Cove and Monument Valley regions of northeastern Arizona. The projects sought to identify archaeological resources within the mine boundaries and gather ethnographic information regarding past mining activities at these sites. The results of this ethnoarchaeological work provide insight into the daily activities and family life of Navajo uranium mine workers, as well as historic data useful for Navajo Nation land managers planning remediation activities at the abandoned mine sites. The article concludes with a series of reflections about the nature of conducting archaeological work at uranium industry sites that might be of interest to others engaged in similar work. [ABSTRACT FROM AUTHOR]

Australia’s pro-nuclear lobby is calling for a major expansion of the country’s nuclear infrastructure, including an ambitious and controversial proposal to dispose of some of the world’s high-level nuclear waste on Australian territory. These calls have recently attracted the support of the premier of the state of South Australia, who launched a royal commission to explore the economic opportunities offered by the nuclear fuel cycle—even though Australian federal law forbids the development of nuclear energy. But due to a series of tragic blunders and abuses over the past 60 years, a serious lack of trust has been created between the nuclear industry and the Australian people—for which successive federal governments must share some of the responsibility. This has bred widespread public cynicism toward all things nuclear, which is likely to prevent bipartisan consensus on all but the most modest nuclear proposals. [ABSTRACT FROM AUTHOR]

The current work addresses the study of the recovery of rare earth elements (REE) from acid mine water by using cationic exchange resin. The acid water was obtained from a closed uranium mine in Brazil. Ion exchange experiments were carried out in batch with three different resins at 25 ± 0.5°C and pH values 1.4, 2.4 and 3.4 (natural). Data were adjusted to the Langmuir equation in order to calculate the maximum loading capacity (qmax) of the resins. The results of qmax for individual REE revealed that the resins present higher loading for La in detriment to the other REE. The Dowex 50WX8 and Lewatit MDS 200 H resins demonstrated favourable sorption profiles to REE, evidenced by values of equilibrium factor (RL) and higher values of the Langmuir constants (b). The separation factors ( α H R E E L R E E ) indicates that resins are more selective for light REE at all pH studied. The selectivity of the resins for the REE can be described as light REE > heavy REE. The pH 1.4 and 3.4 are more favourable for the recovery of REE. [ABSTRACT FROM AUTHOR]

Research into radionuclide leaching behavior in the treatment of low-level radioactive waste solidification has been a widespread concern. Bioleaching of uranium was carried out using Aspergillus sulphureus isolated from El-Sella ore material. This area is located in the southern eastern desert of Egypt. The maximum bioleaching of U(VI) was found to be 83.1 % at these optimum conditions: 9 days incubation period, 0.5% pulp density, 30 °C incubation temperature at shaking speed 175 rpm. Glucose and NH4Cl were considered the best carbon and nitrogen sources for fungal growth through direct bioleaching process. A. sulphureus exhibits good potential in generating varieties of organic acids which effective for bioleaching of uranium. It produced 45.2 and 17 µg/ml from gallic and ellagic acids, respectively in the culture filtrate under the optimum conditions. This work represented the environmental technology for leaching of uranium where this is method is more save and low cost. [ABSTRACT FROM AUTHOR]

Evolving atmospheric oxygen levels during the early Earth history had a profound impact on Earth's surface processes, especially on the mineralization of redox-sensitive elements such as iron (Fe) and Uranium (U). Here we present a review of the effect of the Great Oxidation Event (GOE) that started at ~2.44 Ga on the style of Uranium mineralization with reference to Indian uranium occurrences. GOE was responsible for the initiation of intense chemical oxidative weathering of the Neoarchean U-rich K-granites mobilizing U from the source rocks in the U6+ soluble state. By 2.32 Ga, anoxic/euxinic conditions in the oceans developed on a global scale mainly due to the bacterial sulphate reduction that was triggered by enhanced sulphate concentrations in the ocean caused by the GOE. Such a development of anoxic/euxinic conditions acted as a sink for the hexavalent U by reducing it to tetravalent state and its deposition on a large scale in the strata of post-2.0 Ga age. Majority of Uranium deposits of India are hosted in the Proterozoic rock formations unlike the global pattern, where the Phanerozoic strata are more prominent. Among the uranium reserves that occur in the Precambrian sequences of India, the mineralization during the 1.9 to 1.6 Ga time window constitute ~75% of the total. In India, the Archaean U occurrence is exemplified by the Bababudan quartz pebble conglomerates (~2.72 Ga) hosting detrital uraninite, while the Proterozoic period witnessed a marked change with most of the U deposits being of redox-controlled-type in sedimentary formations. A model is proposed to explain such an enrichment in Uranium reserves among the Proterozoic strata of India. It appears that the emplacement of large ion lithophile element (LILE)-enriched granites, the onset of GOE and ensuing oceanic anoxic conditions played a major role in controlling the Uranium mineralization of the late Paleoproterozoic in the Indian scenario. [ABSTRACT FROM AUTHOR]

As a techno–economic study, column and vat leaching experiments of low-grade uranium mineralization were implemented to obtain a deep understanding of reagent consumption during the uranium leaching stage. The leaching index (β) is a techno-economical parameter that must be considered during the decision-making stage of project development in order to arrive at an optimal point based on solution consumption and recovery. The results indicate that 21.2 and 32 g of acid are consumed using an acid concentration of 20 and 40 g/L, respectively, to have a 1% increase in the uranium recovery. Also, 1.0 and 1.8 L solutions using 0.1:1 and 0.2:1 sprinkling intensities are consumed, respectively, to have a 1% increase in the uranium recovery during column leaching period. The results of the leaching index (β) of vat leaching indicate that 4.1 m3 solution and 88 kg acid are consumed to have a 1% increase in the uranium recovery after 90 day. The overall consumed acid after this period was 17.6 kg/ton of ore. [ABSTRACT FROM AUTHOR]

Thousands of abandoned uranium mines (AUMs) exist in the western United States. Due to improper remediation, windblown dusts generated from AUMs are of significant community concern. A mobile inhalation lab was sited near an AUM of high community concern ("Claim 28") with three primary objectives: to (1) determine the composition of the regional ambient particulate matter (PM), (2) assess meteorological characteristics (wind speed and direction), and (3) assess immunological and physiological responses of mice after exposures to concentrated ambient PM (or CAPs). C57BL/6 and apolipoprotein E-null (ApoE−/-) mice were exposed to CAPs in AirCARE1 located approximately 1 km to the SW of Claim 28, for 1 or 28 days for 4 hr/day at approximately 80 µg/m3 CAPs. Bronchoalveolar lavage fluid (BALF) analysis revealed a significant influx of neutrophils after a single-day exposure in C57BL/6 mice (average PM2.5 concentration = 68 µg/m3). Lungs from mice exposed for 1 day exhibited modest increases in Tnfa and Tgfb mRNA levels in the CAPs exposure group compared to filtered air (FA). Lungs from mice exposed for 28 days exhibited reduced Tgfb (C57BL/6) and Tnfa (ApoE−/-) mRNA levels. Wind direction was typically moving from SW to NE (away from the community) and, while detectable in all samples, uranium concentrations in the PM2.5 fraction were not markedly different from published-reported values. Overall, exposure to CAPs in the region of the Blue GAP Tachee's Claim-28 uranium mine demonstrated little evidence of overt pulmonary injury or inflammation or ambient air contamination attributed to uranium or vanadium. [ABSTRACT FROM AUTHOR]

Interaction between uranium(VI) and aminopolycarboxylic acids could significantly influence the chemical behavior of uranium(VI) in the processing and disposal of nuclear wastes. Trans-1,2-cyclohexanediaminetetraacetic acid (CDTA) is a commonly used aminopolycarboxylic acid, but its complexation with uranium(VI) has not been sufficiently studied. In this study, stability constants of CDTA protonation and U(VI)-CDTA complexes at different temperatures were measured by potentiometry. Their enthalpies and entropies were obtained from van't Hoff plots. As a result, four U(VI)-CDTA species, UO2(H2CDTA), UO2(HCDTA)-, UO2CDTA2- and UO2(OH)CDTA3-, were identified at pH 3-6 and their coordination modes in solution were demonstrated by thermodynamic studies. The proposed coordination modes of UO2(H2CDTA) and UO2(HCDTA)- in solution differ from the reported crystals; the former is bidentate bonding with one carboxylate and the latter is tridentate bonding with iminodicarboxylate. [ABSTRACT FROM AUTHOR]

The sediment-hosted uranium deposit at Four Mile West is buried by 130–150 m of sediments yet has a landscape as well as a surficial geochemical and biogeochemical expression of the mineral system. The landscape expression includes exposure of stratigraphy with now-oxidised redox overprinting (including 'roll-fronts') equivalent to those in the buried mineralisation. The landscape also includes morpho-tectonic expressions of faults that have been responsible for the development and preservation of mineralisation. Most importantly, this faulting has produced an embayment in the range front corresponding to a down-faulted area on the plains that has hosted throughflow of surface and groundwater and preservation of underlying, chemically reduced, ore-hosting Mesozoic and Cenozoic sediments. Landscape geochemical and biogeochemical expressions of buried mineralisation are best represented in U2/Th and selected trace elements, rather than simply elevated U contents in isolation. These associations are especially important for distinguishing between the U-rich expressions of buried, sediment-hosted mineralisation and laterally transported U-rich detritus from the adjacent ranges. The surficial geochemical and biogeochemical expression of the underlying mineralised substrate, with higher U2/Th, is best expressed in regolith carbonates, river red gums and potentially ants and macropod droppings. The mechanism proposed for this vertical geochemical transfer is in part tree-root depth penetration (or burrowing in the case of ants) but most importantly upward groundwater flux. Important groundwater fluctuations are connected to low-frequency–high-intensity rainfall periods that drive groundwater recharge and significantly raises the water-table towards the land surface, especially along faults and fractures near the range front and the immediately adjacent plains. During seasons with high rainfall, this groundwater rise may even express itself as water discharge at springs along the range front. Other media, such as stream sediments, soils and inland tea tree are more closely associated with expressing lateral physical dispersion and re-accumulation of U within the landscape. This study shows that surficial mapping, geochemistry and biogeochemistry within a landscape processes/landscape system context can be invaluable for the detection of, and exploration for, buried sediment-hosted uranium mineral systems, and most especially understanding more about the behaviour of chemical elements in the Australian landscape. [ABSTRACT FROM AUTHOR]

In order to alleviate the sulfate accumulation in uranium hydrometallurgy process, the sulfate accumulating path was studied and a new elution process was proposed. The eluate composition as a function of eluent volume during the conventional and new elution process was studied. The result showed that pre-elution of saturated resin with 0.5–0.8 BV (bed volume) mother liquor was beneficial to the discharge of accumulated sulfate and could alleviate the accumulation of sulfate. Field tests showed that the new process ensured more stable production and reduced the amount of wastewater. Finally, the mechanism of the pre-elution process was analyzed. [ABSTRACT FROM AUTHOR]

Airborne geophysics provides one of the most relevant data for uranium exploration. However, the application of radiometric surveys is decreasing considerably as the depth of exploration is increasing. Notwithstanding, there is still a large potential for radiometric data, especially using recent data processing techniques such as machine learning methods. In this work, we propose a new method to detect uranium anomalies through regression using the Random Forest machine learning algorithm (RF). The RF regression allows combining airborne geophysical data to predict the expected uranium content, which represents the uranium content generated by environmental effects such as lithology and pedogenesis. Therefore, the deviation (Ud) between the measured uranium and the expected uranium represents the secondary effects such as weathering, soil alteration, hydrothermal alteration or mineralisation process. We evaluated the relevance of the geophysical parameters proposed by previous authors in the prediction of the expected uranium (thorium, thorium potassium ratio, uranium potassium ratio, and Total Gradient Amplitude). Randomly selecting only 10% of the database as training data, we estimate the expected uranium with an R2 = 0.99 concerning the measured uranium. To assess the reliability of the Ud anomalies, we employed the proposed methodology in the Carajás Mineral Province (CMP), Brazil. In the CPM, the Ud anomalies showed a clear correlation with the several Iron Oxide Copper–Gold deposits (IOCG) and some IOCG-related and granite-related prospects. In situ measurements with a portable gamma-ray spectrometer in the Salobo mine supported the uranium anomalies. The Ud map also highlighted contrasts within granites that correlate with previously reported granitic facies. Therefore, the Ud map generated by RF regression is useful in setting exploration targets for conventional and unconventional uranium resources, as well as in high-detail granitic facies mapping. [ABSTRACT FROM AUTHOR]

Uranium uptake, translocation and its effects on leaf anatomy in vetiver grass (Vetiveria zizanioides L. Nash) grown in hydroponics were investigated at a wide range of concentrations. At concentrations below 200 ppm (1, 5, 25, 100, and 200 ppm) almost 90–95% of uranium was depleted from the medium within 3 days of treatment, while at other concentrations viz., at 318, 500, 619, 1,000, 5,000, 7,500, and 11,900 ppm, it reached a maximum between 7 and 14 days, with a marginal increase in the depletion thereafter. Most of the uranium could be recovered from plants at concentrations below 200 ppm. On the contrary, a significant reduction in the recovery of uranium was noticed at higher concentrations and the percentage of recovery dropped from 82% at 318 ppm to 35% at 11,900 ppm. While most of the uranium taken up by the plants could be recovered from roots at lower concentrations, a preferential translocation of the element to shoot occurred at concentrations beyond 1,000 ppm. Histological studies of leaves from plants treated with 1,000 ppm uranium displayed the formation of multilayered cells between the epidermis and vascular bundles on the adaxial side in the distal regions of the leaves. The plants were also found to tolerate and survive the radiological and chemical constituents of both uranium mill tailings soil as well as various effluents of uranium mine and mill operations. Further, they could also survive in uranium ore containing 600 ppm of triuranium octoxide (U3O8) and could withstand the amendment of ore with citric acid. The ability of vetiver to take up uranium from solutions to high levels and its survival in effluents, mill tailings soil, and ore coupled with its ecological characteristics makes it an ideal plant for phytoextraction of uranium. [ABSTRACT FROM AUTHOR]

Investments and progress of mineral projects depend on the quantity (tonnage) and quality (grade) of mineral resources and reserves. This study examines the impact of various criteria used in the classification of mineral deposits or parameters defining these criteria. The data used in this study include the uranium assay analysis from 127 exploratory boreholes, which were then subjected to a three-directional variography after statistical studies to identify regional anisotropy. A grade block model was built using the optimal parameters of variograms and with the help of kriging estimator. Then, by using different methods of estimating the block model uncertainty including kriging estimation variance, block error estimation, kriging efficiency and slope of regression, classification of mineral reserves was carried out in accordance with the JORC standard code. Based on different cut-off grades, the tonnage and average grade were calculated and plotted. An innovative quantitative method based on the distribution function of the mentioned parameters and the fractal pattern of separation of populations was used for the classification of mineral reserves. The existence of the least difference between the use of standard and fractal patterns in the slope of regression method indicated less error and was a proof of more reliable results. [ABSTRACT FROM AUTHOR]

The spatial distribution of six heavy metals (Cd, As, Zn, Pb, Cr, and Cu) in the soil of a decommissioned uranium mining area was investigated and their potential environmental risk was assessed. Soil samples were collected along the main riversides enclosing the mining area. The heavy metal distribution was determined by geospatial interpolation. Pearson correlation coefficient and principal component analysis were used to locate the sources of pollution which are the mine ore as natural source, and dressing plants and tailing area from human activity. The results indicate that the average concentrations of As and Cd strongly exceed the recommended EQSS (Environmental Quality Standard for Soils of China) limits at all sampling sites, whereas Zn concentrations were found to be slightly over the limit only at sampling sites close to the mining area. The concentrations of Cr, Cu and Pb were all within the recommended limits. Environmental risk was assessed using the toxicity characteristic leaching procedure defining the degree to which extend the metal is released into the solution. High leaching rates were found only for Zn and Cd, suggesting that together with its high concentrations Cd is the most toxic metal around the mining area, followed by As. [ABSTRACT FROM AUTHOR]

Uranium mining and ore processing are known to be harmful to the environment and human health if the waste generated is not managed properly. The aim of the present study is to determine the radiological indices in the mill tailings and review the possible attempts to utilize and minimize its hazardous effect. The activity concentrations of natural radionuclides, 238U, 232Th, 226Ra, and 40K have been measured by gamma spectrometry using HP-Ge detector. The average activity concentrations of 238U, 232Th, 226Ra, and 40K in the tailings wastes were 2071.8, 59.92, 6921.262, and 445. 57 Bq/kg respectively which are higher than the international average limit. The ranges of hazard indices such as Radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), γ-radiation hazard index Iγ, Dose rate (nGy/h) and annual effective dose equivalent (AED), were estimated. Uraniumm isotopic ratios in the ore –material and mill tailing samples indicate migration out of radionuclides to the surrounding environment causing contamination and many dangerous diseases. Fairly, all investigated tailing waste samples do not satisfy the universal standards, the studied wastes relatively still have high uranium contents and need reprocessing. [ABSTRACT FROM AUTHOR]

The South China Uranium Province (SCUP) contains the largest number of discovered uranium deposits in China. This province includes seven uranium mineralization belts, at Wuyishan, Taoshan–Zhuguang, Chenzhou–Qinzhou, Gan–Hang, Xixia–Luzong, Mufushan–Hengshan, and Xuefengshan–Jiuwandashan. The uranium deposits can be classified according to their ore-hosting rocks into four general types: granite-, volcanic-, black-shale-, and sandstone-related. These uranium deposits crop out at the peripheries of Cretaceous–Neogene (K–N) redbed basins or are connected to the basins by NE–SW- to NNE–SSW-trending regional faults. Most of the volcanic-related uranium deposits were formed during the mid-Cretaceous (118 to 88 Ma); granite-related deposits have a wider range of ages from 124 to 11 Ma; the black-shale-related deposits have ages of 120 to 7 Ma; sandstone-related deposits yield ages of 111 to 22.5 Ma. As such, these four types of uranium deposits in South China have similar ages, irrespective of location, and are similar in age to K–N redbed basins in this region. δDVSMOW(fluid) and δ18OVSMOW(fluid) values of the volcanic-related uranium deposits generally range from – 105.9‰ to – 38.0‰ and – 11.1‰ to +5.3‰, respectively. The black-shale-related uranium deposits yield δDVSMOW(fluid) and δ18OVSMOW(fluid) values of – 74.5‰ to – 33.0‰ and – 4.4‰ to 9.3‰, respectively. However, the granite-related uranium deposits have a much wider range of δDVSMOW(fluid) and δ18OVSMOW(fluid) values from – 104.4‰ to – 23.1‰ and – 9.4‰ to +7.3‰, respectively. H–O isotopic compositions of the SCUP ore-forming fluids are similar to those of basinal fluids, again demonstrating the link between the uranium deposits and the basins. The spatial–temporal relationships and fluid isotopic similarities between the K–N basins and uranium mineralization indicate that the uranium deposits of the SCUP are genetically related to the K–N redbed basins, and are unconformity-related uranium deposits. [ABSTRACT FROM AUTHOR]

Based on statistics from the World Nuclear Association, Kazakhstan has the highest uranium production in the world. Most of the uranium in the country is mined via in-situ leaching and the accurate classification of lithologic composition using electric logging data is economically crucial for this type of mining. In general, this classification is done manually, which is both inefficient and erroneous. Information technology tools, such as predictive analytics with Supervised Machine Learning (SML) algorithms and Artificial Neural Networks (ANN) models, are nowadays widely used to automate geophysical processes, but little is known about their application for uranium mines. Previous experiments showed an ANN accuracy of about 60% in the task of lithological interpretation of logging data. To determine the upper limit of the accuracy of machine learning algorithms in such task and for indirect assessment of the experts' influence, a digital borehole model was developed. This made it possible to generate a complete set of data avoiding subjective expert assessments. Using these data, the work of various ML algorithms, both simple (kNN) and deep learning models (LSTM), was evaluated. [ABSTRACT FROM AUTHOR]

Between 2000 and 2018, China's number of operating nuclear reactors increased more than 10-fold.[16] By 2019, China had 45 operating reactors - fewer than half of the 98 operating reactors in the United States, but more than the number in Russia (36) and nearly as many as in France (58). Uranium mining in Namibia began in 1976, when Rio Tinto opened the Rössing mine. Only 10% of the 50 reactors under construction around the world are in North America or Western Europe.[64] If China's nuclear energy strategy is successful, it is likely to become a model for many of the 30 countries that are currently either starting or considering nuclear energy programs.[65] Namibia is on the front lines of intensified uranium mining, but additional uranium exploration and mining projects are underway in at least 12 African countries. [Extracted from the article]

Halophiles are a group of microorganisms found in salty environments such as marine ecosystems, salty meat, salt evaporation ponds, and salt mines. The present study aimed to investigate the diversity of halophilic microorganisms in Saghand Desert (Yazd Province, Iran). To this end, water, soil, and salt crystal samples were taken from Saghand Desert. In order to isolate and culture bacteria and archaea, they were separately inoculated in solid 10% Halophiles Moderate (HM) medium and 23% Modified Growth Medium (MGM). After incubation at 37 °C, all obtained halophilic isolates were analyzed in terms of phenotypic, microscopic, and biochemical characteristics. After eliminating repetitive strains, 26 isolates from each representative sample were selected for DNA extraction and molecular studies. Phylogenetic analysis showed that archaeal isolates belonged to genera Natrinema and Haloarcula and bacterial isolates were from genera Halomonas, Bacillus, Staphylococcus, and Gracilibacillus. The isolation of these genera from many regions of Iran and their enzymatic activity indicate the high biodiversity of these microorganisms in Iran and their potentials for use in biotechnology, which should be considered by industries more seriously. [ABSTRACT FROM AUTHOR]

The 1993 Nunavut Agreement was intended to help resolve disputes over resource extraction and facilitate responsible development in Nunavut. However, conflicts have persisted. In the Kivalliq region, debates over uranium mining and mining in caribou calving grounds have caused divisions between different representative organizations created by the Nunavut Agreement. Scholars have explained these conflicts with reference to the structures created by the Nunavut Agreement, especially the corporate structure of the territory's Inuit organizations. While this is an important factor driving these conflicts, I argue that the system of land rights created by the Nunavut Agreement, especially the extinguishment of Aboriginal title, is also an important causal factor in these disputes. I begin with an overview of the concept of Aboriginal title and its extinguishment in British-Canadian law. Next, I discuss the Nunavut Agreement's provisions for land rights, especially the exchange of Aboriginal title over a large territory for fee-simple ownership over relatively small parcels of land. This is followed by an examination of the conflicts over uranium mining and mining in calving grounds. I conclude that the provisions of the Nunavut agreement intended to provide 'certainty' for capital investment have in some cases had the opposite effect by fueling ongoing conflicts. [ABSTRACT FROM AUTHOR]

Uranium from Africa was, and remains, a major source of fuel for atomic weapons and power plants throughout the world. Uranium for the Hiroshima bomb, for example, came from the Belgian Congo. During any given year of the Cold War, between 20 percent and 50 percent of the Western world’s uranium came from African places: Congo, Niger, South Africa, Gabon, Madagascar, and Namibia. Today, there is a renewed uranium boom throughout the continent. The author writes on the ambiguities of the nuclear state, and the state of being nuclear, and why the nuclear designation matters. She looks at two countries to uncover different dimensions of nuclearity: Niger, which has long struggled with France over the price of its uranium; and Gabon, where cancer and other illnesses related to four decades of uranium production remain invisible. [ABSTRACT FROM PUBLISHER]

The final two pages consist of a photo gallery of Respino with various other Italian mineral collectors under the guise of "the importance of social relationships in amateur mineralogy." The ore deposits section consists of the following subsections: metalliferous skarns; fluorite- and baryte-bearing metal deposits; manganese deposits; and uranium deposits. The chapter is not so much about being able to recognize minerals using the classification scheme and crystal systems, but in how Italian minerals are represented in these groupings. [Extracted from the article]

Acid mine drainage samples were collected from the central basin of the Witwatersrand basin in South Africa to study the removal of radioactivity. The samples were analyzed for gross alpha/beta activity, specific radionuclides, metals and anions concentration. The pH of the acid mine drainage samples was then varied and ion-exchange column experiments were carried out to remove radioactivity from acid mine drainage. The gross alpha activity ranged between 60 and 75 Bq/L and gross beta activity ranged from 56 to 70 Bq/L. The speciation of uranium, thorium and radium was modelled using Joint Expert Speciation System. The speciation had a big influence on the removal of radioactivity from acid mine drainage using ion exchange resin. The optimum pH was determined to be 8. Acid mine drainage samples treated at this pH showed gross alpha activity below the detection limit of 0.03 Bq/L for all samples and gross beta activities below 5 Bq/L for 9 of the 10 treated samples [ABSTRACT FROM AUTHOR]

Algal biomass has a great potential for cleaning metal pollutants from wastewaters. In the present study, biosorption of three metals i.e., vanadium, titanium, and uranium which are appeared in contaminated effluent during the uranium ore mines processing or in sludge resulting from pure UO2 processing are investigated by a new strain of Galdieria sulphuraria, SBU-SH1 KY651246, which is isolated from a sulfur hot spring. The optimum biosorption situations and efficiency of isolated alga are investigated for each metal. Looking at the results, it can be concluded that G. sulphuraria SBU-SH1 is amenable to biosorption and has a favorable efficiency. [ABSTRACT FROM AUTHOR]

A few plant species are recognized for uranium bioaccumulation, particularly as upper accumulator. Uranium has a dynamic impact on the physiological, biochemical, and photochemical reactions. Therefore, the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), soluble sugar, protein, photochemical reactions, and accumulation of uranium characteristics were studied in Bidens pilosa L. while applying altered concentrations of uranium in the form of C4H6O6U. It was done to measure the capacity of B. pilosa L. to remediate uranium from wastewater. In this study, the results showed that B. pilosa L. not only has the ability of uranium accumulation but it can accumulate in the upper parts i.e. leaves and stem. Overall it can accumulate as much as 1538 mg/kg on a dry weight basis. Uranium accumulation is a complex process which changes both physiological and biochemical index in plant species under different treatments. SOD decreased in leaves and stem in response to all treatments whereas POD and CAT increased at treatment 3 and 72 h up to 1335 μ/g-FW and 47 μ/g-FW at 72 h, respectively. This increase was followed by a downward trend. The correlation coefficient between fluorescence ratio Fv/Fm and the concentrations of uranium treatment were significantly negative i.e. -0.928. The Fourier transform infrared spectroscopy (FTIR) analysis also highlighted that uranium does not change the basic chemical composition of B. pilosa L., but has an effect on the contents of chemical constituents. From the study, it is concluded that B. Pilosa L. has shown a capacity for uranium enrichment, especially as an upper accumulator. [ABSTRACT FROM AUTHOR]