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We here present the normal dynamics technique, which recasts the Newton's equations of motion in terms of phonon normal modes by exploiting a proper sampling of the reciprocal space. After introducing the theoretical background, we discuss how the reciprocal space sampling enables us to (i) obtain a computational speedup by selecting which and how many wave vectors of the Brillouin zone will be considered and (ii) account for distortions realized across large atomic distances without the use of large simulation cells. We implemented the approach into an open-source code, which we used to present three case studies: in the first one, we elucidate the general strategy for the sampling of the reciprocal space; in the second one, we illustrate the potential of the approach by studying the stabilization effect of temperature in α-uranium; and in the last one, we investigate the characterization of Raman spectra at different temperatures in MoS2/MX2 transition metal dichalcogenide heterostructures. Finally, we discuss how the procedure is general and can be used to simulate periodic, semiperiodic, and finite systems such as crystals, slabs, nanoclusters, or molecules. [ABSTRACT FROM AUTHOR]

Metallic fuels hold numerous advantages over conventional uranium dioxide fuels and are a key component of several liquid metal-cooled advanced reactor concepts including sodium fast reactors. These fuels undergo rapid swelling during early burnup; consequently, they spend most of their reactor lifetime in a porous state. The presence of this porosity alters many of the mechanical properties of the fuel including creep impacting fuel deformation during axial swelling. This work investigates the creep behavior of the porous fuel using a spark plasma sintering technique. Creep tests were performed for the first time on porous α-phase uranium and uranium with 10 wt. % zirconium (U-10Zr) samples. The samples of α-phase uranium and U-10Zr were fabricated from depleted uranium by spark plasma sintering and subjected to uniaxial compressive creep testing. Calculated stress exponents were found to be 2.6 ± 1.6 and 5.7 ± 1.4 for α-U and U-10Zr, respectively, and calculated activation energies were found to be 61.6 ± 1.1 kJ / mol for α-U. The creep data were also used to evaluate existing porosity inclusive in creep models. [ABSTRACT FROM AUTHOR]

This paper investigates the relationship between political constraint and investor perception of policy risk using an analysis of the reaction of Australian and Canadian uranium company stocks to the Fukushima nuclear disaster in 2011. Our dataset traces 933 projects of 322 uranium firms located across 36 countries and posits a U-shaped relationship between political constraint and investor perceptions of policy risk. Using an event study methodology as applied to the natural quasi-experiment arising from the event, we link heterogeneous changes in stock returns to the policy risk in the uranium project locations of the firms. The results corroborate the expected relationship and hold even after we control for home-country bias. [ABSTRACT FROM AUTHOR]

Uranium-based materials are valuable assets in the energy, medical, and military industries. However, understanding their sensitivity to hydrogen embrittlement is particularly challenging due to the toxicity of uranium and the computationally expensive nature of quantum-based methods generally required to study such processes. In this regard, we have developed a Chebyshev Interaction Model for Efficient Simulation (ChIMES) that can be employed to compute energies and forces of U and UH3 bulk structures with vacancies and hydrogen interstitials with accuracy similar to that of Density Functional Theory (DFT) while yielding linear scaling and orders of magnitude improvement in computational efficiency. We show that the bulk structural parameters, uranium and hydrogen vacancy formation energies, and diffusion barriers predicted by the ChIMES potential are in strong agreement with the reference DFT data. We then use ChIMES to conduct molecular dynamics simulations of the temperature-dependent diffusion of a hydrogen interstitial and determine the corresponding diffusion activation energy. Our model has particular significance in studies of actinides and other high-Z materials, where there is a strong need for computationally efficient methods to bridge length and time scales between experiments and quantum theory. [ABSTRACT FROM AUTHOR]

Western countries are eager to reduce their dependence on Russian-origin nuclear fuel but are hindered by capacity constraints in uranium conversion and enrichment. Governments hope to enhance supply security via uranium stockpiles and subsidies, yet such measures risk disrupting the market and are unlikely to accelerate capacity expansion in the short term. Recognizing the complexity of market dynamics and the fact that market adjustments are already taking place, governments should focus on providing market players with the incentives and certainty they need to protect their individual conversion and enrichment supply chains. [ABSTRACT FROM AUTHOR]

Bentonite containing smectite group clay minerals is an industrial raw material with a wide range of uses. In this study, the concentration of uranium, thorium, and radioactive potassium in ninety bentonite samples collected from quarries in Turkey was determined using an energy-dispersive X-ray fluorescence spectrometer. The concentrations of uranium, thorium and potassium varied from 0.4 to 18.2 with an average of 4.3 mg/kg, 5.4 to 53.4 with an average of 22.7 mg/kg and 0.3 to 3.4 with an average of 1.4 mg/kg, respectively. The radiogenic heat generation caused by the ionising radiation emitted from these radioactive elements in bentonite samples was calculated in the range of 0.9 to 6.6 µW/m3 with an average of 2.8 µW/m3. [ABSTRACT FROM AUTHOR]

In this study, Adsorption characteristics of uranium from nitrate media onto a commercially accessible strong cation exchange resin, Marathon C, were investigated. The characteristics of Marathon C, before and after adsorption of uranium, were determined using scanning electron microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The influence of the different parameters, which may affect the process of uranium adsorption process from synthetic solutions and applying on real sample from uranium purification unit, had been tracked. Specifically, impacts of initial uranium concentration (40–300 mg/L), PH (1–8), phase ratio (0.2–1.2 g/L), contact time (2–360 min.) and temperature (& 25–50°C) on uranium removal, were studied. In addition, the sorption kinetics and equilibrium parameters were assessed. At the optimum conditions, the adsorption capacity of uranium at PH 4, 1 g Marathon C/L and 120 min were found to be nearly 131.58 mg g−1 at room temperature (& 25°C). The kinetics and isotherm studies could show that the uranium adsorption onto Marathon C is following the models of pseudo-second-order and Langmuir isotherm, respectively. The thermodynamic parameters had indicated that the adsorption of uranium is an exothermic and spontaneous process (∆H = −64.27 ± 0.01, ∆G = −22.57 ± 0.02). The detected results of uranium adsorption could reveal that Marathon C is a suitable material for adsorption of uranium from nitrate media and applying on real sample from uranium purification unit. [ABSTRACT FROM AUTHOR]

Three brown algal biomasses namely, Sargassum latifolium, Padina pavonica and Dictyota dichotoma were used in the uranium biosorption from the processing effluent of Gattar pilot plant project, Eastern Desert, Egypt. Biosorption enhancement process was studied, and the uranium loading capacities were optimised at 1 h contact time, 1/1000 solid/liquid ratio, 200 ppm uranium as initial feed concentration, pH 4 and all experiments were at room temperature. The maximum capacities reached 190, 177 and 170 mg/g for Sargassum latifolium, Padina pavonica and Dictyota dichotoma, respectively. SEM examination for the three concerned algae showed different morphological and surface structural changes such as shrinking and appearance of large cavities. FTIR study revealed that, there are many functional groups contributed in uranium biosorption mechanism such as carboxylic, sulphonate, hydroxyl and amine groups. The obtained experimental data for the three concerned algal biomasses were comparable with pseudo-second-order model and best described by Langmuir isotherm model. 0.1 N HCl was used for desorption of the loaded uranium on the three algal masses. By applying the most effective alga (Sargassum latifolium) with fixing the optimum concluded conditions in the treatment of Gattar pilot plant effluent, it was clear that almost all elements and nearly uranium complete concentrations were recovered from the waste water and the water can be safely reused again. The present work concluded that the phyco-sorption is a sufficient, low costing, eco-friendly way for the recovery of variable elements and purification of waste water solutions. [ABSTRACT FROM AUTHOR]

Theoretical evaluation of experimental extraction data of U (VI) from nitric acid solutions by tri-n-butyl phosphate (TBP) loaded on macro reticular polymer SM-7 was verified using Thomas and Yan models. These data are represented by breakthrough relations at different conditions; flow rate, concentrations and interfering ions. Comparing correlation coefficients (R2) of both models, it was found that R2 equal 0.96 for Thomas model comparing to 0.88 for Yan one, indicating that Thomas model is convenient for evaluation of that extraction process. The calculated, theoretically, value of (qTh) was found to be almost equal to (qexp) the practical one. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A host matrix with a potential of incorporating heavy element like uranium, that have several forms of stabilization is the key interest. Uranium-doped BaAl2B2O7 is synthesized through solution combustion synthesis method. The luminescence studies indicate suitability of this alumino borate matrix to stabilize uranium as uranate (UO66−). The uranium life-time values suggest uranium to be surrounded by two different environments with varied defect concentration. The site occupancy of uranium in BaAl2B2O7 is probed through EXAFS studies. It is observed that the preferred sites for uranium incorporation is the Al3+ regular lattice sites. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extracting uranium from the ocean is considered a promising solution for meeting nuclear fuel consumption. To date, porous adsorbents fabricated with polyamidoxime (PAO), particularly macroporous PAO hydrogels, have demonstrated exceptional potential for uranium capture from natural seawater. Herein, a novel macroporous PAO hydrogel is developed via a well‐designed wax‐casting method. The developed wax‐casted macroporous PAO (WMPAO) hydrogel particles are subsequently encapsulated in alginate‐polyacrylic acid (A‐PAA) beads. The obtained A‐PAA@WMPAO beads exhibit a high qmax of 687.4 mg‐U/g‐Ads. and show a good adsorption capacity of 8.23 mg g−1 toward uranium in simulated seawater. Additionally, A‐PAA@WMPAO shows good reusability with a 31.2% reduction in uranium adsorption capacity after five consecutive adsorption‐desorption cycles. Furthermore, A‐PAA@WMPAO displays satisfactory extraction efficiencies of 95.9–99.5% for U‐spiked coastal seawater after 10 days of adsorption, achieving adsorption capacities ranging from 207.5 to 3963.2 µg g−1. Particularly, with the utilization of 4 mg of A‐PAA@WMPAO beads, a high adsorption capacity of 4.79 mg g−1 for uranium from 10 L of coastal seawater within 15 days is achieved. These obtained results comprehensively demonstrate the significant potential of the fabricated A‐PAA@WMPAO beads for uranium capture from natural seawater. [ABSTRACT FROM AUTHOR]

Extraction of uranium from seawater is considered to be an effective way to solve the shortage of uranium resources, and the development of efficient adsorption functional groups is the key to uranium extraction. In this work, the complexation of uranyl cations with a series of diamidoxime and bifunctional (amidoximate‐carboxylate, amidoximate‐phosphate) ligands has been probed by quantum chemical calculations. For most of the uranyl complexes, the amidoxime groups adopt η2 mode to uranyl cations. Based on bonding analyses, we found that the uranyl complexes with methyl‐substituted ligands (H2L′) possess stronger covalent interactions than those with phenyl‐substituted ligands (H2L). Consequently, the uranyl complexes with H2L' are more stable in the extraction process according to thermodynamic analysis. The amidoximate‐phosphate bifunctional ligand (H2L3′) has stronger extraction capacity to uranyl cations than other ligands, which is related to the relatively lower decomposition energy, and it shows selectivity in seawater for uranyl cations over vanadium ions, which may be a potential ligand for uranium extraction. Therefore, the introduction of synergistic functional groups, i. e. the bifunctional ligands, enhance the extraction properties of uranyl cations. This work improves understanding of synergistic ligands, and may contribute to design and development of efficient ligands for recovery of uranium from seawater. [ABSTRACT FROM AUTHOR]

This review examines the advances and applications of metal–organic frameworks (MOFs) in the field of the extraction of uranium from various sources, focusing on their potential to address critical issues in nuclear fuel cycles. MOFs, characterized by their high surface area, tunable porosity, and chemical versatility, offer a promising alternative to traditional extraction methods. The review paper provides a comprehensive analysis of the synthesis strategies, functionalization techniques, and adsorption mechanisms of MOFs tailored for uranium capture. Furthermore, the review discusses the challenges and future directions in the field, emphasizing the need for scalable production, real-world application testing, and environmental impact assessment. This review aims to highlight the potential of MOFs to improve the sustainability and efficiency of uranium extraction processes. [ABSTRACT FROM AUTHOR]

A rapid in situ synthesis of electrochromic covalent organic frameworks (EC‐COFs) was proposed by using green electrochemical interface polymerization of N,N,N',N'‐tetrakis(4‐aminophenyl)‐1,4‐benzenediamine (TPDA) and 2,5‐dihydroxyterephthalaldehyde (DHBD). The synthetized TPDA‐DHBD films exhibit stable polymorphic color variations under different applied potentials, which can be attributed to the redox state changes of bis(triphenylamine) and imine electroactive functional groups within the COFs skeleton. TPDA‐DHBD represents markedly different electrochromisms from red to cyan due to the steric hindrance effect caused by the presence of UO22+, demonstrating the unique tunability of COFs materials. This work offers a new feasible idea for rapid EC‐COFs synthesis and tunable EC‐COFs realization. [ABSTRACT FROM AUTHOR]

Background: Parathyroid cysts account for a small percentage of parathyroid lesions and are more prevalent in females. Cystic parathyroid hyperplasia is exceptionally rare, with only two cases reported thus far. This case report provides the readers with the first multimodality imaging in cystic parathyroid hyperplasia as well as the authors' first experience in using a 4D computed tomography (CT) scan in our institution while the systematic review will comprehensively search and present similar cases. Main text: The literature search started and ended on August 4, 2024. We searched five academic databases: MEDLINE, Cochrane Library, Pubmed, Science Direct, and Google Scholar. The studied population was all patients with cystic parathyroid gland hyperplasia, confirmed by histopathology. A total of 205 articles were initially identified, out of which 29 duplicates were promptly eliminated, leaving 176 unique articles for screening. Following the evaluation of titles and abstracts, ultimately only two studies were included in the systematic review. A 61-year-old male presented with recurrent abdominal pain and weight loss. Ultrasound revealed a left neck mass, cystic. The laryngeal CT scan agreed with the ultrasound while the Technetium-99 sestamibi scan suggested a thyroid lesion. A 4D CT scan confirmed a lobulated cystic lesion in the left parathyroid region. The patient underwent successful surgery, and histopathology confirmed parathyroid hyperplasia with a pseudocyst appearance. Conclusions: This case report presents the first imaging multimodality in cystic parathyroid hyperplasia while highlighting the rarity of this case, with two cases worldwide. In addition, this article describes our institution's first experience with a 4D CT scan. [ABSTRACT FROM AUTHOR]

Uranium ditelluride (UTe2) is the strongest contender to date for a p-wave superconductor in bulk form. Here we perform a spectroscopic study of the ambient pressure superconducting phase of UTe2, measuring conductance through point-contact junctions formed by metallic contacts on different crystalline facets down to 250 mK and up to 18 T. Fitting a range of qualitatively varying spectra with a Blonder-Tinkham-Klapwijk (BTK) model for p-wave pairing, we can extract gap amplitude and interface barrier strength for each junction. We find good agreement with the data for a dominant py-wave gap function with amplitude 0.26 ± 0.06 meV. Our work provides spectroscopic evidence for a gap structure consistent with the proposed spin-triplet pairing in the superconducting state of UTe2. [ABSTRACT FROM AUTHOR]

The source of uranium is an important research topic related to the exploration of sandstone-type uranium deposits, and potential uranium sources in deep basins are often overlooked. Black organic-rich shale is a common uranium-bearing rock in deep sedimentary basins. However, relatively few studies have investigated the migration of uranium during hydrocarbon generation in and release from uranium-rich shale. In this study, the uranium-rich shale in the Chang 7 member of the Yanchang Formation of the Upper Triassic in the Ordos Basin was selected to investigate the migration of uranium and other trace elements during the thermal maturation of uranium-rich shale via a semiopen pyrolysis simulation system. The gas and liquid products as well as the solid residue were thoroughly analysed by means of multiple instruments. The results showed that uranium significantly migrated before hydrocarbon generation (Ro < 0.61%), with a leaching rate between 12.1% and 18.8%. The leaching rate of uranium during the hydrocarbon generation stage (0.63% < Ro < 1.35%) was relatively low, ranging from 0 to 7.2%. Cu, Pb, Zn, Mo, and other trace elements also migrated considerably during the early stage of thermal evolution, with leaching rates ranging from 2.9 ~ 11.6%. The yield of low-molecular-weight organic acids (LOAs) was the highest in the early stage of thermal maturity, and the LOA yield exhibited a good correlation with the leaching rates of Cu, Pb, Zn, Co, Mo, etc. The generation of LOAs from source rocks was conducive to the leaching and migration of trace elements. Moreover, according to a statistical analysis of published geochemical data, the total organic carbon (TOC) content, uranium content, and U/TOC ratio in shale decreased significantly with increasing burial depth, indicating that uranium migrated significantly upon kerogen hydrocarbon generation during thermal evolution. Therefore, uranium-rich shale is an important deep uranium source in sedimentary basins. [ABSTRACT FROM AUTHOR]

2,6-Dipicolinoylbis(N,N-dialkylthioureas) and H2LR2 react with uranyl salts and a supporting base (e.g., NEt3) under formation of monomeric or oligomeric complexes of the compositions [UO2(LR2)(solv)] (solv = donor solvents) or [{UO2(LR2)(µ2-OMe)}2]2–. In such complexes, the uranyl ions are commonly coordinated by the "hard" O,N,O or N,N,N donor atom sets of the central ligand unit and the lateral sulfur donor atoms remain uncoordinated. Their individual structures, however, depend on the reaction conditions, particularly on the equivalents of NEt3 used. An unprecedented, selective hydrolysis of the uranium-coordinating bis(thioureato) ligands results in an S/O donor atom exchange at exclusively one thiourea side-arm, when an excess of NEt3 is used. The resulting trimeric uranyl complexes are isolated in fair yields and have a composition of [(UO2)3(L2Et2)2(µ2–OR)(µ3-O)]–. H2L2Et2 represents the newly formed 2,6-dipicolinoyl(N,N-diethylthiourea)(N,N-diethylurea) and R = H, Me, or Et. {L2Et2}2– binds to the uranyl units via the pyridine ring, the dialkylurea arm, and the central carbonyl groups, while the thiourea unit remains uncoordinated. The central cores of the products consist of oxido-centered triangular {(UO2)3O}4+ units. The observed reactivity is metal-driven and corresponds mechanistically most probably to a classical metal-catalyzed hydrodesulfurization. The hydrolytic thiourea/urea conversion is only observed in the presence of uranyl ions. The products were isolated in crystalline form and studied spectroscopically and by X-ray diffraction. The experimental findings are accompanied by DFT calculations, which help to understand the energetic implications in such systems. [ABSTRACT FROM AUTHOR]

The synthesis, isolation, and characterisation of well-defined low-valent actinide complexes are reviewed with a main focus on compounds featuring uranium and thorium metal centres in formal oxidation states ≤ +3. The importance of the ligand environment in enabling access to these highly reactive species, as well as its influence on ground state electronic configurations and their reactivity, are emphasised. Furthermore, we highlight cyclic voltammetry (C.V.) studies as a more widely used method that can guide the synthesis of these highly reducing species. [ABSTRACT FROM AUTHOR]

Charnockitic rocks are a suite of granulitefacies plutonic rocks that include dominantly granitic-tonalitic and partly dioritic rocks. The Na-rich endmembers of the charnockite series, including dioritic to tonalitic rocks, are also termed enderbites. Charnockitic rocks are the main component of the cratonic-type lower continental crust in Precambrian cratons worldwide. These rocks are generally considered to be products of the anatexis of the lower crust under high-to ultrahigh-temperature conditions and play a key role in stratification between upper and lower crustal layers as well as the cratonic stabilization (cratonization) of Precambrian continents, although further study is required to gather detailed information about these rocks. In this study, a group of igneous enderbites (dioritic-tonalitic charnockites) from Eastern Hebei, North China Craton, is investigated. Zircon U-Pb dating reveals that the enderbites formed at ca. 2.46 Ga, which coeval with the regional granulite-facies metamorphic overprinting. The enderbites are primarily composed of clinopyroxene, orthopyroxene, plagioclase, and quartz, with minor amphibole, biotite, K-feldspar, and Fe-Ti oxides. The rocks are characterized high Fe2O3 T + MgO (9.80-15.9 wt%), Cr 71.0-292 ppm), and Ni (41.2-107 ppm) contents, as well as low Al2O3 (13.9-16.6 wt%) and K2O (1.07-2.43 wt%) contents, with high Na2O/K2O ratios (1.51-4.43) and low Sr/Y 24.5-49.5) ratios. Moreover, these rocks are enriched in light rare earth elements (LREEs), (La/Yb)N = 8.06-17.8, and yield weak Eu anomalies, (Eu/Eu* = 0.80-1.18), with negative Th, U, Ta, Nb, and Ti anomalies. Various mineral thermobarometers, oxybarometers, and hydrometers are used to constrain the crystallized P-T-ƒO2-H2O conditions of the enderbites. These rocks crystallized at high temperature (860-1000 °C), crystallization pressure (8.0 ± 1.0 kbar), and H2O-poor (1.5-2.4 wt%) conditions, with oxygen fugacities (QFM) of 0.0-3.0, which suggests "hot" (high-temperature) and "dry" (water-poor) crystallization conditions. The enderbites also have heterogeneous in situ zircon Hf-O isotopic compositions: eHf(t) = 2.4-7.5; d18O = 5.78‰-7.74‰. These new data, combined with trace element characteristics, suggest that the enderbites were derived from the partial melting of metabasites, and that assimilation and fractional crystallization controlled the compositional variation in the enderbites. Further thermodynamic and geochemical modeling suggests that the anatexis of Mg-Fe-rich metabasite under ultrahigh-temperature (>1000 °C) and H2O-poor (1.0-1.5 wt%) conditions at a low crustal depth (~9.0 kbar) could yield a melt composition comparable to that of the observed enderbites. Postcollisional lithospheric extension and mafic magma underplating prompted the partial melting of lower crustal metabasite at ultrahigh temperatures and normal lower crustal depths, resulting in the formation of enderbites. This study demonstrates that the enderbites could be formed by ultrahigh-temperature anatexis of metabasite with amphibole dehydration melting (Pl + Amp Opx + Cpx + melt) and offers robust evidence of the genetic links between the ultrahigh-temperature anatexis of basic rocks and the generation of enderbites. In addition, the occurrence of ca. 2.46 Ga enderbites may mark the final cratonization of the North China Craton, and the ca. 2.50-2.45 Ga tectono-thermal event was an ultrahigh-temperature metamorphicanatexis process rather than simple regional granulite metamorphic overprinting. Therefore, the generation and emplacement of enderbites involved not only a magmatic process but also an element redistribution process in the lower crust, which has important implications for stabilization of the North China Craton at ca. 2.5 Ga. [ABSTRACT FROM AUTHOR]

2,6-Dipicolinoylbis(N,N-dialkylthioureas), H2LR, readily react with uranyl salts under formation of monomeric or dimeric complexes of the compositions [UO2(LR)(solv)] (solv = donor solvents such as H2O, MeOH or DMF) or [{UO2(LR)(µ-OMe)}2]2− (1). In such complexes, the uranyl ions are exclusively coordinated by the "hard" O,N,O or N,N,N donor atom sets of the central ligand unit and the lateral sulfur donor atoms do not participate in the coordination. Different conformations have been found for the dimeric anions. The bridging methanolato ligands and the four uncoordinated sulfur atoms can adopt different orientations with respect to the equatorial coordination spheres of the uranyl units. The presence of non-coordinated sulfur atoms offers the opportunity for the coordination of additional, preferably "soft" metal ions. Thus, reactions with [AuCl(PPh3)], lead acetate or acetates of transition metal ions such as Ni2+, Co2+, Fe2+, Mn2+, Zn2+, or Cd2+, were considered for the syntheses of bimetallic complexes. Various oligometallic complexes with uranyl units were prepared: [{UO2(LR)(μ-OMe)(Au(PPh3)}2] (2), [(UO2)3Pb2(LR)4(MeOH)2(μ-OMe)2] (3), [M{UO2(LR)(OAc)}2] (M= Zn, Ni, Co, Fe, Mn or Cd) (R = Et: 5, RR = morph: 6), or [(UO2)(NiI)2(LR)2] (7). The products were extensively studied spectroscopically and by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The Journal of Analytical Atomic Spectrometry (JAAS) published in 2024 by The Royal Society of Chemistry covers a wide range of topics related to advances in the analysis of metals, chemicals, and materials. The issue includes technical notes on simplified instrumental protocols for trace Nd and Hf isotope measurements, as well as papers on various topics such as uranium measurement in a glass matrix and data fusion techniques for improving accuracy in machining processes. The journal aims to provide a platform for research on analytical atomic spectrometry and its applications in diverse fields. [Extracted from the article]

The storage and management of nuclear waste materials require the detection of uranium, but traditional analytical methods are unsuitable for radioactive environments. The enhancement methods of uranium in glass matrices using fiber-optic laser-induced breakdown spectroscopy are still underdeveloped. Using an optical diagnostic system coupled with fast photography, shadowgraphy, and optical emission spectroscopy, the evolution of laser-induced plasma generated from a glass matrix under spatial confinement is studied. The plasma evolution image illustrates the temporal consistency between the compression of plasma width and the enhancement of luminescence intensity. Two enhancements were observed when the plate spacing was smaller than the plasma, which might be due to the high density of the core plasma or a synergistic effect of plasma expansion and shockwave confinement. Under spatial confinement, there is a 3–4-times enhancement in the intensity of uranium spectral lines and a 2–4 times enhancement in the signal-to-noise ratio. Several calibration curves are established under spatial confinement based on U II 409.01 nm, U II 367.01 nm and U I 358.48 nm. The lowest limit of detection (LOD) of uranium reaches 95 ppm, which supports the application of FO-LIBS in the detection of uranium-containing nuclear waste materials. [ABSTRACT FROM AUTHOR]

The potential pollution risks and characteristics of heavy metal pollution in surface streams were assessed in a decommissioned uranium tailing. The results demonstrated that the concent of seven heavy metals in the tailing were comparatively high and were beyond the environmental quality standard limits of surface water. Correlation and enrichment factor studies demonstrated that mining operations were the main source of contamination. According to pollution evaluation indices, there was a high risk of contamination and notable enrichment and pollution features for Tl, Mo, Mn, U, and Al in the tailing. Ni and Cd were mildly contaminated and enriched. [ABSTRACT FROM AUTHOR]

238U and 234U concentrations, 238U/234U ratios and Na, Ca, Mg, K, Al, As, Cd concentrations were measured in selected surface waters (streams, rivers and lakes), ground waters (dug wells) and underground waters (drill wells and thermal waters) in Quang Nam and Da Nang provinces, Central Vietnam. The mineralization was < 500 mg L−1 and Al, As, Cd contents were a few tenths of µg L−1. 234U and 238U activities were between 0.47–27.6 mBq L−1 and 0.6–15.0 mBq L−1 respectively, these values are lower than WHO recommended limits. Uranium contents trended as Urivers < Ustreams < Ulakes < Udig wells < Uthermal water < Udrill wells. The 234U/238U ratio ranged from 0.69 to 2.31 with 1.26 on average. For groundwaters, the ratio scattered around one. Effects of Nong Son uranium deposit located in Quang Nam region were not observed. [ABSTRACT FROM AUTHOR]

A radiochemical procedure has been developed for the quantification of uranium and thorium isotopes in NORM samples from the ceramic industry, such as zirconium sands, zirconium flours, micronized zircon, pigments and personal aerosol filters. The method is based on a fusion pretreatment with borate salts, a separation with anion exchange resins and alpha-particle spectrometry measurement. This method is an alternative to gamma spectrometry when the amount of sample is extremely small (2–10 mg) as in the case of aerosol filters, or there is no secular equilibrium in the 238U and 232Th chains, as in the ceramic pigments. The method has been validated with different ceramic materials and the comparison of the results with gamma measurements. Its reproducibility was also checked with different sample masses. [ABSTRACT FROM AUTHOR]

The 234U/238U activity ratio can be used to delineate the last redox surface between the lower and middle members of Um Bogma Formation in Allouga Quarry, southwestern Sinai, Egypt. The activity concentrations of radionuclides were measured for nine samples collected from the base to top of the geologic section. The 234U/238U activity ratio was used to express the oxidation or reduction prevailing. The lower (base) samples showed oxidation state, while the upper (top) samples showed reduction state. From uranium age results, the uranium leaching process in lower member is more recent than the uranium accumulation process in middle member. [ABSTRACT FROM AUTHOR]

Uranium is a highly hazardous heavy metal and radionuclide. The distribution of uranium in rock, soil, fruit, and water has been measured in the Balod area. Samples were collected using one square kilometer griding technique from Jhalmala Paragaon, Parsoda, Dewerbatt, Pakurbatt, and Jagarata Deur tarai. The distribution of uranium is quantified within the ranges of 0.7–3.6 (ppb) in soil, 0.5–4.4 ppb in rock, 0.2–52.6 ppb in groundwater, and 0.2–0.7 ppb in fruit.The presence and movement of uranium has been verified through a systematic statistical investigation, and its mobility in environmental components has been established. [ABSTRACT FROM AUTHOR]

Spergularia rubra (L.) J. Presl & C. Presl has a mycorrhizal resistance that leads to increased uranium uptake. The results show that 35% of the 238U is retained in the carbonate fraction and 59% in the residual or non-reactive fraction. 226Ra shows a different pattern with an average association of 19% in the organic matter fraction, 10% in the carbonate compounds and the remaining 71% in the residual fraction. The relationships between the activity concentrations of 238U and 226Ra in the soil fractions and in Spergularia were found to be statistically representative of the carbonate and organic matter fractions, respectively. [ABSTRACT FROM AUTHOR]

In this study, we report the facile synthesis of diglycolamic acid (DGA)-coated titanium dioxide (TiO2) microspherical nano-particles (TMP-DGA) for effective extraction of uranium (U(VI)) from aqueous solutions. The physical properties of the as-prepared adsorbents were carefully investigated using BET and XRD, and the presence of DGA groups was verified using FTIR, TG–DTA, and SEM–EDAX. Batch experiments were performed to assess the extraction efficiency of U(VI). The Langmuir adsorption isotherm capacity of TMP-DGA towards U(VI) was determined to be 175.87 mg g−1 at pH 6, which is substantially greater than the maximum adsorption capacity of commercial TiO2. The addition of DGA groups to TiO2 enhanced the number of active sites and enabled excellent coordination with the U(VI) species. In the presence of several contemporaneous metal ions, it has also displayed strong selectivity towards U(VI). The plausible mechanism include electrostatic attraction between U(VI) species and the DGA groups. The results of these studies show that the reported material has a remarkable ability to be utilized as an adsorbent for the removal of U(VI) from aqueous medium. [ABSTRACT FROM AUTHOR]

The presence of uranium in groundwater has become a growing concern due to its potential health implications. This abstract focuses on the assessment of uranium concentrations in groundwater samples collected from the Kangra district. The study employed rigorous sampling and analysis techniques to evaluate the extent of uranium contamination and its distribution in the groundwater resources of the region. A comprehensive survey was conducted across various locations within the Kangra district, involving the collection of groundwater samples from different depths and geological formations. The collected samples were subjected to meticulous laboratory analysis, employing advanced spectroscopic method of LED fluorimeter to quantify uranium concentrations. The findings reveal varying levels of uranium in the groundwater samples, with concentrations ranging from minimal to elevated levels. The distribution of uranium was observed to be influenced by geological factors, hydrological characteristics, and anthropogenic activities. This research contributes to the understanding of little uranium contamination in the Kangra district's groundwater, serving as a valuable resource for policymakers, researchers, and stakeholders striving to ensure the safety and sustainability of the region's water resources. [ABSTRACT FROM AUTHOR]

Among uranium extraction materials, amidoxime polymers are very promising. But the conformation of molecular chains is not well understood. Herein, conformation behavior of polyamidoxime (PAO) was analyzed via molecular dynamics. In water, the conformation of PAO is extended, its radius of gyration (Rg) is 12.5 Å. However, the Rg of polyacrylonitrile is merely 6.2 Å. The PAO conformation collapses due to uranyl and sodium ions. Moreover, small angle X-ray scattering showed that Rg from 11.6 to 11.0 nm after uranium adsorption. Overall, this work will be beneficial to the design of new uranium adsorbents. [ABSTRACT FROM AUTHOR]

Radioactive elements have coexisted in our environment and the health risks assessment for humans associated with the presence of these radioactive elements in the environment is necessary. This study was conducted in the Mansa district of Punjab for estimating the health risks to the people living in the region. 22 Soil and water samples from collected from various locations in the district. The range of Ra, Th and K in the soil samples varied from 28.09 Bq/kg to 55.91 Bq/kg, from 23.32 Bq/kg to 79.64 Bq/kg and from 189.22 Bq/kg to 425.58 Bq/kg, respectively. Doses to different organs have been calculated and ultimately Expected lifetime cancer risk varies from 0.79 × 10−3 to 1.46 × 10−3 for indoor and 0.08 × 10−3 to 0.15 × 10−3 for outdoor which is well below the safe limit of 3.5 × 10−3. The average concentration of Uranium in groundwater samples is found to be 37.95 µg/L, which is above the World Health Organisation's (WHO) standard limit of 30 µg/L. But the values of Life time average daily dose (LADD) and Hazard quotient (HQ) is found to be below the standard limit by WHO. Bones are found to be the most affected organ followed by Kidneys from the study of organ specific doses. The study suggests more intense detailed survey of Mansa district by increasing the number of sampling sites and correlate it with the other water and soil quality parameters. [ABSTRACT FROM AUTHOR]

The general population's health is directly related to the quality of the water used for drinking. As a result, research will be done on the radiation levels in the groundwater in the Charkhi Dadri area in the Indian state of Haryana. Using the LED Fluorimetry Technique, the concentration of uranium in drinking water samples taken from sources including hand pumps and tube wells of varying depths from the district will be determined. 40 water samples are gathered from various districts sites. With average value of 41.30 μg/L, variations in uranium level were noted within the range of 2–99 μg/L. The average value of uranium concentration is within the safe limit of 60 μg/L as recommended by Atomic Energy Regulatory Board, India but greater than 30 μg/L, the safe limit recommended by World Health Organization (WHO 2011). The value of cancer mortality is varying from 0.03 × 10–6 to 1.4 × 10–6 with mean value of 0.38 × 10–6 and that of cancer morbidity varying from 0.06 × 10–6 to 2.75 × 10–6 with mean value of 0.75 × 10–6. LADD value varying from 0.15 to 7.29 µg kg−1 d−1 with mean value of 1.90 µg kg−1 d−1 and HQ varying from 0.12 to 6.07 with mean value of 1.50. 60% of the samples showed HQ values greater than unity, this shows noteworthy danger of chemical poisonousness of uranium. [ABSTRACT FROM AUTHOR]

The article discusses the discovery and mineralogy of greenlizardite, a hydrated ammonium sodium uranyl sulfate found in the Green Lizard mine in San Juan County, Utah. The mineral formed in a secondary crust on a mined wall underground and is associated with other sulfate minerals. The history of mining in the White Canyon district, particularly the uranium boom during World War II and the subsequent decline in production, is also detailed. The Green Lizard mine, now closed with a bat-accessible grate, has been the site of mineral collection and research, leading to the discovery of new minerals. [Extracted from the article]

In order to facilitate the dissolution of these insoluble nuclear debris from the Fukushima Daiichi NPS accident, it is necessary to investigate methods of pulverizing them to increase their surface area. For uranium and zirconium oxides in nuclear fuel debris, we proposed a pretreatment method using a redox method to achieve powdering. In this study, the simulated nuclear fuel debris pellets with uranium-zirconium ratio 9:1 and 1:1, and the pellet containing U, Zr, Fe, Gd, Nd and Si (65%:10%:10%:5%:5%:5%) were subjected to heating oxidation experiments in an oxygen atmosphere and reduction experiments after oxidation. The feasibility of pulverizing uranium-zirconium solid after heating and oxidation was demonstrated. And the product of the powder after redox reaction, uranium dioxide to triuranium octoxide was confirmed by XRD. Thus increasing the surface area required for dissolution or chemical conversion to soluble compounds can be expected. [ABSTRACT FROM AUTHOR]

Uranium mineralization related to Na-metasomatism is known as Na-metasomatite or albitite-type. They represent the fourth-largest uranium resource globally and constitute fifty thousand tons of U resources. The present work gives details about well-known Na-metasomatic uranium occurrences worldwide in terms of structures, metasomatic stages, geochemical characteristics, fluid inclusions, and compositions of stable isotopes. The host rocks are granite, granitoid, and metamorphosed volcano-sedimentary rocks, and these rocks experienced two/three deformational stages. U mineralization is mainly confined to faults and characterized by granitic intrusive, cataclasis, mylonitization, and albitization. The albitized rocks exhibit two to three metasomatic and late hydrothermal stages. The first stage is marked by the replacement of pre-existing host minerals during a ductile shear regime. The second stage is related to U mineralization contemporaneous with the brittle deformation. The albitized rocks exhibit depletion in Si, K, Ba, and heavy rare-earth elements relative to the host rocks and enrichments in Na, Ca, U, Zr, P, V, Sr, and light rare-earth elements. U-enrichment is positively correlated with Na, Mo, Cu, and high-field strength elements. The pressure–temperature (P-T) conditions of U mineralization are considered to be epithermal and mesothermal. Fluid inclusion studies indicate that the mineralizing fluids were rich in Na+, Mg2+, Cl−, CO2, H2O, F−, and PO43− and meteoric–magmatic derived. The geological processes responsible for the genesis of Na-metasomatic U deposits of the North Delhi Fold Belt (India) are comparable with some international examples, i.e., Australia, Ukraine, Cameroon, Brazil, Guyana, China, and the USA. [ABSTRACT FROM AUTHOR]

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The airborne gamma-ray spectrometric (AGS) data of the north Wadi Qena area were used to map the radioactive potentiality and uranium migration. Examination of the potassium (K), equivalent uranium (eU), equivalent thorium (eTh), and ternary maps displayed the areas of potential radioactivity. The results of uranium favorability (U2) index revealed that the granitic rocks, Rakhiyat, Esna, and Sudr formations, have high uranium potential. On the other hand, the computed uranium migration maps (original uranium (Uo), migrated uranium (Um), uranium migration rate (P%), eU-eTh/3.5, and eU point anomaly) allowed the delineation of migration patterns (inward and outward) for all the rock units of the area under study. The inward uranium migration distinguished the Sudr, Esna, and Rakhiyat formations, while the other rocks displayed outward uranium migration. The investigation of geological structural data indicated that the research area was influenced by NNW-SSE, NE-SW, NNE-SSW, ENE-WSW, and WNW-ESE trends. These structures most likely had a significant influence on uranium movement and migration (in and out) of the rocks in the current study area. [ABSTRACT FROM AUTHOR]

Selective uranium adsorption in high acidic conditions is essential and extremely challenging. Based on the potential uranium adsorption capacity of phosphazene‐based frameworks, a design of constructing fully heterocyclic covalent phosphazene‐based polymers (CPPs) is proposed by introducing potential coordination structural units rich in Nitrogen (N), Oxygen (O), and other heteroatoms. The as‐prepared CPP‐N and CPP‐O (CPP‐N/O) with unique ─N═P─NH─C═N‐ and ─N═P─O─C═N─ full heterocyclic structures. Uranium adsorption experiments reveal that under the synergistic coordination of N, O, and other heteroatoms, the saturated sorption capacity of uranium under 1 mol L−1 (M) HNO3 can reach 270 and 275 mg g−1 for CPP‐N and CPP‐O, respectively. The adsorption capacities of CPP‐N and CPP‐O are greater than 130 and 100 mg g−1at 1‐6 M acidity, respectively. Moreover, the selectivity of CPP‐O for uranium under competing ions can reach up to more than 80%. Both CPP‐N/O show stable and excellent uranium adsorption capacity under high acidity, which lays a path for the design and preparation of novel uranium adsorbents applicable to highly acidic environment. [ABSTRACT FROM AUTHOR]

The works of assessing the pollution posed by metals in agricultural areas in developing countries are limited. This study aims to assess metal concentrations and pollution indices of parent materials and soils representing the mantle and oceanic crust units of the ophiolite in the Eastern Mediterranean region, specifically in Kahramanmaraş Province. A total of 88 samples, comprising 44 soil (0–30 cm) and 44 parent material (90 + cm), were collected from the study area. Arsenic (As), mercury (Hg), selenium (Se), uranium (U), molybdenum (Mo), tin (Sn), and cesium (Cs) concentrations were analyzed in these samples, along with the reference metal, iron (Fe). Pollution levels were assessed using enrichment factor (EF) and contamination factor (CF) calculations. Results showed that elemental concentrations (Hg, Se, U, Mo, Sn, and Cs) in soils from the mantle and oceanic crust generally reflected those of the parent material. However, the average As concentration in soils from oceanic crust and mantle units was notably elevated, showing a 3 to fourfold increase compared to the parent material. Based on pollution index values, soils from these units demonstrated a moderate level of enrichment (2 < EF < 5) for As, while other elements (Hg, Se, U, Mo, Sn, and Cs) fell into the low enrichment class (EF < 2). Furthermore, the CF index indicated significant contamination (3 < CF < 6) for As. These findings suggest As contamination in soils from different units of the ophiolite (mantle and oceanic crust), potentially resulting from agricultural chemicals like pesticides and fertilizers. [ABSTRACT FROM AUTHOR]