The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhua...The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhuakeng uranium deposit has a high radioactive heat production rate(avg.5.50μW/m³)and a low Th/U ratio(avg.2.62).Uranium-rich granite and its alteration zone within the upper crust(0-5 km depth)contribute about 45%of the total radioactive heat production,wich is crucial for controlling geothermal resource distribution.For uranium-thermal at tectonic plate margins,a symbiotic geological model was proposed:Firstly,subduction of the Pacific Plate caused upwelling of the asthenosphere,generating a high heat-flow background.Secondly,heat transfer is enhanced by major faults such as the Youdong and Mianhuakeng faults.Subsequently,uranium was mobilized,transported,and enriched within the granite through deep siliceous hydrothermal activity and associated alteration.Ultimately,the uranium enrichment in granite leads to increased radioactive heat production,resulting in local thermal anomalies.This model provides a theoretical support for exploring and developing uranium-thermal symbiotic resources in South China.展开更多
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis...The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness.展开更多
Knowing the precise relationship between fuel loading and reactivity is essential for guiding reactor criticality extrapolation and online refueling in molten salt reactors(MSRs).This study aims to explore and explain...Knowing the precise relationship between fuel loading and reactivity is essential for guiding reactor criticality extrapolation and online refueling in molten salt reactors(MSRs).This study aims to explore and explain the linear relationship between reactivity and the reciprocal of uranium concentration in thermal-spectrum MSRs.By applying neutron balance theory,we analyzed the neutron absorption cross sections of various nuclides in single-lattice models with varying fuel concentrations.Our findings reveal a simple linear correlation between reactivity and the reciprocal of uranium concentration,which can be explained from the perspective of nuclear reaction cross sections that adhere to the 1/v law in the thermal neutron spectrum.Furthermore,we identified that the neutron absorption single-group cross sections of structural materials and carrier salts exhibit an approximately linear relationship with the fission single-group cross section of ^(235) U;similarly,the reciprocal of ^(235)U’s fission cross section exhibits an approximately linear relationship with uranium concentration.This linear relationship deviates as the volume fraction of molten salt increases,due to a greater proportion of neutrons being captured in the resonance energy spectrum.However,it remains valid for molten salt volume fractions up to 25%and demonstrates broad applicability in the physical design and operation of thermal molten salt reactors.展开更多
Many adsorbents have been developed for uranium recovery to ensure global energy and environmental security.However,most reported adsorbents involve complex preparation process and rely heavily on petrochemical feedst...Many adsorbents have been developed for uranium recovery to ensure global energy and environmental security.However,most reported adsorbents involve complex preparation process and rely heavily on petrochemical feedstocks,which undoubtedly increases carbon emissions from production in the nuclear industry.Here,a biomass aerogel(CS-BT)is prepared by the facile cross-linking of chitosan and bayberry tannins with glutaraldehyde.U(Ⅵ)can be adsorbed by hydroxyl groups on CS-BT aerogel via chelation,and the maximum adsorption capacity of the obtained aerogel to U(Ⅵ)is 140 mg·g^(-1)and the removal rate reaches up to 99%(at 298.15 K,pH=5.0).The pseudo-second-order kinetics model and Freundlich model can better match the adsorption process of CS-BT aerogel,implying that its adsorption is a chemical adsorption process dominated by multilayer adsorption.The thermodynamic results show that the adsorption process of U(Ⅵ)by CS-BT aerogel is spontaneous and exothermic.Hence,our biomass aerogel can effectively extract uranium from water,contributing to the sustainable development of the nuclear industry.展开更多
As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term...As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term uranium supply but is challenged by ultra-low uranium concentrations and ion interference.To overcome these issues,we design three diketopyrrolopyrrole-based covalent organic frameworks(COFs)via a synergisticπ-extended lock and carboxyl-functionalized anchor molecular engineering strategy.Among them,TPy-DPP-COF features a covalently lockedπ-conjugated structure that enhances planarity,optimizes energy alignment,and minimizes exciton binding energy,thereby promoting charge transfer and suppressing recombination.Concurrently,carboxyl groups enable uranyl-specific coordination and create local electric fields to facilitate charge separation.These features contribute to the outstanding performance of TPy-DPP-COF,which achieves a high uranium adsorption capacity of 16.33 mg g−1 in natural seawater under irradiation,with only 29.3%capacity loss after 10 cycles,surpassing industrial benchmarks.Density functional theory(DFT)calculations and experimental studies reveal a synergistic photocatalysis-adsorption pathway,with DPP units acting as active sites for uranium reduction.This work highlights a molecular design strategy for developing efficient COF-based photocatalysts for practical marine uranium recovery.展开更多
One of the main issues in designing optimum tapered cascades for uranium enrichment for annual fuel production in a power reactor is whether to employ large(fat)or small(thin)cascades.What will be the permissible and ...One of the main issues in designing optimum tapered cascades for uranium enrichment for annual fuel production in a power reactor is whether to employ large(fat)or small(thin)cascades.What will be the permissible and optimal ranges of the number of machines that can be used in a cascade?For the first time,the permissible and optimal ranges of the number of gas centrifuges that can be utilized in a cascade were investigated using two types of centrifuges,and the performance of small and large tapered cascades was discussed.The particle swarm optimization algorithm(PSO)has been used to optimize tapered cascades.The results show:(1)For the first centrifuge,41 cascades(91≤n≤4897)and for the second centrifuge,49 cascades(18≤n≤3839)with small and large sizes can be used in enrichment facilities,and the best cascade for them has 530(with 23 stages)and 39(with 7 stages)centrifuges,respectively.(2)For both centrifuges,when 600≤n(number of centrifuges=n),the large cascade performance changes are relatively insignificant.(3)For both types of gas centrifuges,the annual los s of separation power in enrichment facilities is approximately 1.25%-4.82%of the total separation work required.展开更多
Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.Dur...Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.During the implementation of this project,the authors summarized the metallogenic regularity of uranium resource in China systematically,through the researches of geological characteristics of uranium resource,uranium deposits type（genetic and prediction type）,temporal and spatial distribution,and metallogenic series.Based on the investigation of present situation and progress in uranium exploration,this paper proposes the uranium deposits in China should be divided into 4 classes,9 types,21 subtypes in genetic,and 50 types in prediction;suggests to divide China into 29 uranium metallogenic belts and 20 uranium prospective area,and constructs 20uranium-polymetallic metallogenic series,through summarizing temporal and spatial distribution characteristics and metallogenic regularity of uranium deposits in China.The above research is beneficial to the comprehensive understanding of regional uranium metallogenic regularity,and will direct the uranium exploration in the future.展开更多
The study aims to investigate uranium species in the sediments of the natural-technogenic system within a sludge storage facility in Russia.The relevance of this work is underscored by the need to assess the geochemic...The study aims to investigate uranium species in the sediments of the natural-technogenic system within a sludge storage facility in Russia.The relevance of this work is underscored by the need to assess the geochemical mobility of radionuclides,a critical factor for predicting their migration and environmental impact.The objective of the research was to determine the uranium species in both peat and sedimentary rock samples of the sludge storage facility and the adjacent area.Laboratory analyses included XRD,XRF analysis using synchrotron radiation,and scanning electron microscopy to study the composition and properties of minerals.The uranium species were further identified using a modified Tessier sequential extraction method.The results revealed that uranium predominantly occurs in a stable silicate-bound form(up to 80%)in sedimentary rocks,indicating minimal geochemical mobility.In contrast,in peat deposits,uranium is primarily associated with manganese and iron oxides(30–60%)as well as organic matter(5–40%),with the most mobile forms constituting less than 5%.The decrease in uranium concentration with distance from the facility was attributed to sorption onto organic matter and co-precipitation with mineral compounds,manganese and iron oxides,which serve as effective natural sorbents.The findings highlight the critical role of organic matter and metal oxides in limiting uranium migration,thus identifying them as key components in the formation of natural barriers for radionuclides.These results are crucial for assessing environmental risks associated with radioactive waste management and for developing strategies to minimize the ecological impact of sludge storages.展开更多
Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise go...Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata.展开更多
The discharge of effluents containing uranium(U)ions into aquatic ecosystems poses significant risks to both human health and marine organisms.This study investigated the biosorption of U(VI)ions from aqueous solution...The discharge of effluents containing uranium(U)ions into aquatic ecosystems poses significant risks to both human health and marine organisms.This study investigated the biosorption of U(VI)ions from aqueous solutions using corncob-sodium alginate(SA)-immobilized Trichoderma aureoviride hyphal pellets.Experimental parameters,including initial solution pH,initial concentration,temperature,and contact time,were systematically examined to understand their influence on the bioadsorption process.Results showed that the corncob-SA-immobilized T.aureoviride hyphal pellets exhibited maximum uranium biosorption capacity at an initial pH of 6.23 and a contact time of 12 h.The equilibrium data aligned with the Langmuir isotherm model,with a maximum biosorption capacity of 105.60 mg/g at 301 K.Moreover,biosorption kinetics followed the pseudo-second-order kinetic model.In terms of thermodynamic parameters,the changes in Gibbs-free energy(△G°)were determined to be-4.29 kJ/mol at 301 K,the changes in enthalpy(△H°)were 46.88 kJ/mol,and the changes in entropy(△S°)was 164.98 J/(mol·K).Notably,the adsorbed U(VI)could be efficiently desorbed using Na_(2)CO_(3),with a maximum readsorption efficiency of 53.6%.Scanning electron microscopic(SEM)analysis revealed U(VI)ion binding onto the hyphal pellet surface.This study underscores the efficacy of corncob-SA-immobilized T.aureoviride hyphal pellets as a cost-effective and environmentally favorable biosorbent material for removing U(VI)from aquatic ecosystems.展开更多
It has been shown that the age of minerals in which U±Th are a major(e.g.,uraninite,pitchblende and thorite)or minor(e.g.,monazite,xenotime)component can be calculated from the concentrations of U±Th and Pb ...It has been shown that the age of minerals in which U±Th are a major(e.g.,uraninite,pitchblende and thorite)or minor(e.g.,monazite,xenotime)component can be calculated from the concentrations of U±Th and Pb rather than their isotopes,and such ages are referred to as chemical ages.Although equations for calculating the chemical ages have been well established and various computation programs have been reported,there is a lack of software that can not only calculate the chemical ages of individual analytical points but also provide an evaluation of the errors of individual ages as well as the whole dataset.In this paper,we develop a software for calculating and assessing the chemical ages of uranium minerals(CAUM),an open-source Python-based program with a friendly Graphical User Interface(GUI).Electron probe microanalysis(EPMA)data of uranium minerals are first imported from Excel files and used to calculate the chemical ages and associated errors of individual analytical points.The age data are then visualized to aid evaluating if the dataset comprises one or multiple populations and whether or not there are meaningful correlations between the chemical ages and impurities.Actions can then be taken to evaluate the errors within individual populations and the significance of the correlations.The use of the software is demonstrated with examples from published data.展开更多
Fast development of nuclear power plants requires sustainable support of uranium for nuclear fuel.Uranium is the most critical radionuclide to prepare nuclear fuel.However,the extraction of low concentration of uraniu...Fast development of nuclear power plants requires sustainable support of uranium for nuclear fuel.Uranium is the most critical radionuclide to prepare nuclear fuel.However,the extraction of low concentration of uranium in uranium ore or complex systems needs highly efficient selective binding of uranium in the presence of other competing metal ions.The excellent oxidative capacity of excited*UO_(2)^(2+)active species makes uranyl-based materials high photocatalytic performance in phototransformation of organic chemicals into high valuable products under visible light irradiation.In this mini review,the selective preconcentration of uranium through photocatalytic and electrocatalytic strategies was mainly described.The application of uranyl-based materials in photocatalytic conversion and degradation of organic pollutants was summarized.This review reports the utilization of uranium from its first step(i.e.,extraction of uranium for nuclear fuel supply)to its last additional application(i.e.,uranyl-based materials as photocatalysts in transformation and conversion of organic pollutants for environmental pollution treatment)from the viewpoint of“turning uranium wastes into treasure,from waste recycling to reutilization.”In the end of this review,the challenges and perspectives of uranium separation and catalytic properties were described.展开更多
Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(^(235)U)to detect the transient neutrons produced by fis...Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(^(235)U)to detect the transient neutrons produced by fission and then directly measure and quantify uranium;however,the stability and lifetime performance of pulsed neutron sources are the key constraints to its rapid promotion.To address these problems,this study proposes a PFNUL technique for acquiring the time spectrum of dual-energy neutrons(epithermal and thermal neutrons)from the upper and lower detection structures and establishes a novel uranium quantification algorithm based on the ratio of epithermal and thermal neutron time windows(E/T)via a mathematical-physical modeling derivation.Through simulations on well-logging models with di erent uranium contents,the starting and stopping times of the time window(Δt)for uranium quantification in the dual-energy neutron time spectrum are determined to be 200 and 800μs,respectively.The minimum radius and height of the model wells are 60 and 120 cm,respectively,and the E/T values in the time window show an excellent linear relationship with the uranium content.The scale factor is K_(E/T)=1.92 and R^(2)=0.999,which verifies the validity of the E/T uranium quantification algorithm.In addition,experiments were carried out in the Nu series of uranium standard model wells,and the results showed that under di erent neutron source yields,the E/T-based uranium quantification method reduced the relative standard deviation of the scale factor of the uranium content from 33.41%to 1.09%,compared with a single epithermal neutron quantification method.These results prove that the E/T value uranium quantification method is una ected by the change in the neutron source yield,e ectively improves the accuracy and service life of the logging instrument,and has great scientific and popularization value.展开更多
The Erlian Basin is one of the most important multi-energy basins in China.The Baiyanhua area of the Chuanjing depression in the western Erlian Basin has recently become a favorable area for new progress in sandstone-...The Erlian Basin is one of the most important multi-energy basins in China.The Baiyanhua area of the Chuanjing depression in the western Erlian Basin has recently become a favorable area for new progress in sandstone-type uranium prospecting.However,the Cretaceous source-to-sink evolution of the Chuanjing depression in the Erlian Basin is poorly known.This paper presents the systematic geochemical and zircon U-Pb studies on the Saihantala Formation and Erlian Formation in the Baiyanhua area.The data obtained are functionally important for revealing the provenance and tectonic setting of the source rocks.The results show that the upper part of the Saihantala Formation and the lower part of the Erlian Formation are mainly composed of felsic sedimentary rocks.The source rocks originated from a continental margin arc environment in terms of tectonic setting.The detrital zircons ages have the dominant populations at ca.250-270 Ma,with two subdominant age groups at ca.1400-1800 and 1900-2100 Ma,respectively.Combined with the tectono-sedimentary evolution of the Chuanjing depression,we conclude that:(1)the provenance of the Cretaceous strata was mostly sourced from the Baiyanhua uplift;(2)the water depth became shallow in the Southern Sangendalai sag during the middle period of Saihantala,further preventing the formation of coal beds;(3)the formation of Baiyanhua uplift might provide the beneficial tectonic condition for uranium mineralization in the upper Saihantala Formation in southern Sangendalai sag.This is significant for us to understand the space allocation of coal and uranium in Chuanjing depression and evaluate the uranium metallogenic prospects in southern Sangendalai sag.展开更多
Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8...Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8 assay. Apoptosis was measured using flow cytometry. Reagent kits were used to detect carbonyl stress markers malondialdehyde, 4-hydroxynonenal, thiobarbituric acid reactive substances, and protein carbonylation. Aldehyde-protein adduct formation and alcohol dehydrogenase, aldehyde dehydrogenase 2, aldo-keto reductase, nuclear factor E2-related factor 2(Nrf2), and cystathionine β-synthase(CBS) expression were determined using western blotting or real-time PCR. Sulforaphane(SFP) was used to activate Nrf2. RNA interference was used to inhibit CBS expression.Results GYY4137(an H_(2)S donor) pretreatment significantly reversed the uranium-induced increase in carbonyl stress markers and aldehyde-protein adducts. GYY4137 effectively restored the uraniumdecreased Nrf2 expression, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2, accompanied by a reversal of the uranium-decreased expression of CBS and aldehyde-metabolizing enzymes. The application of CBS siRNA efficiently abrogated the SFP-enhanced effects on the expression of CBS, Nrf2 activation, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2 and concomitantly reversed the SFP-enhanced effects of the uranium-induced mRNA expression of aldehyde-metabolizing enzymes.Simultaneously, CBS siRNA reversed the SFP-mediated alleviation of the uranium-induced increase in reactive aldehyde levels, apoptosis rates, and uranium-induced cell viability.Conclusion H_(2)S induces Nrf2 activation and nuclear translocation, which modulates the expression of aldehyde-metabolizing enzymes and the CBS/H_(2)S axis. Simultaneously, the Nrf2-controlled CBS/H_(2)S axis may at least partially promote Nrf2 activation and nuclear translocation. These events form a cycleregulating mode through which H_(2)S attenuates the carbonyl stress-mediated NRK-52E cytotoxicity triggered by uranium.展开更多
The study of uranium isotopes plays a crucial role in advancing our knowledge of nuclear physics,particularly in the realm of isospin and exotic nuclei.This study focused on the ground-state properties of uranium isot...The study of uranium isotopes plays a crucial role in advancing our knowledge of nuclear physics,particularly in the realm of isospin and exotic nuclei.This study focused on the ground-state properties of uranium isotopes ranging from A=203 to A=305.The key physical quantities examined included binding energy,quadrupole deformation,isotopic displacement,single-particle energy levels,and nucleon density distributions.Recent experimental advancements in uranium isotope studies have emphasized the indispensable role of theoretical models in interpreting experimental data.Moreover,the industrial applications of uranium—especially in nuclear energy production and weapons development—underscore the importance and necessity of accurate theoretical insights.The framework of the finite-range droplet model(FRDM)was utilized for comparative analysis because its predictions closely align with the experimental results.Through an analysis of the single-particle energy levels and continuous-state occupancy,this study identified 207 U as the proton drip line nucleus.This research not only deepens our understanding of uranium isotopes but also provides a solid theoretical foundation to guide future experimental investigations.展开更多
Urchin-like W_(18)O_(49),with a large specific surface area(113.738 m^(2)g^(-1))and abundant oxygen vacancies(OVs),was prepared using an active sites tuning and microstructure engineering method.This material was appl...Urchin-like W_(18)O_(49),with a large specific surface area(113.738 m^(2)g^(-1))and abundant oxygen vacancies(OVs),was prepared using an active sites tuning and microstructure engineering method.This material was applied for U(Ⅵ)adsorption for the first time,demonstrating a high adsorption capacity of 567.55 mg g^(-1),which exceeds that of most inorganic adsorbents.Characterization via active site masking experiments and theoretical calculations,etc.,indicated that the excellent adsorption performance toward U(Ⅵ)was due to strong complexation between UO_(2)^(2+)and W–O bond of W_(18)O_(49),facile oxygen vacancy adsorption,and interface electron transfer from W^(5+)to UO_(2)^(2+),which acted as a reducing agent,partially converting U(Ⅵ)to U(IV).Furthermore,W_(18)O_(49)exhibited practical applicability with a removal rate exceeding 82%after 5 cycles,a 92.79%removal rate for real uranium-containing wastewater,and a high uranium recovery rate of 75.96%.Additionally,the synergistic adsorption-photocatalytic effect significantly enhanced U(Ⅵ)extraction,reaching an extraction capacity of 988.0mg g^(-1).This work provides a promising strategy for developing highly efficient U(Ⅵ)WO_(3)-based adsorbents.展开更多
0 INTRODUCTION The Haidewula uranium deposit is located in the Haidewula volcanic basin,which hosts a suite of basic,intermediate to felsic volcanic and subvolcanic rocks,including basalt,trachyte,trachyandesite.Previ...0 INTRODUCTION The Haidewula uranium deposit is located in the Haidewula volcanic basin,which hosts a suite of basic,intermediate to felsic volcanic and subvolcanic rocks,including basalt,trachyte,trachyandesite.Previous geochronological studies of the intrusions within this volcanic basin suggest that they primarily formed during the Silurian and Triassic periods(Dai et al.,2025;Sun et al.,2024;Wang et al.,2024;Zhu et al.,2022;Lei et al.,2021).展开更多
The former uranium ore logging data are mainly used for lithologic identification, stratigraphic division, shale content estimation, preliminary determination of sedimentary environment, accurate determination of spat...The former uranium ore logging data are mainly used for lithologic identification, stratigraphic division, shale content estimation, preliminary determination of sedimentary environment, accurate determination of spatial location, grade, thickness of uranium ore bodies, and determination of casing installation and cementing quality. Uranium-radium balance coefficient is one of the important parameters in uranium exploration, which is of great significance in guiding uranium exploration and studying uranium mineralization law. In this paper, the frequency change of uranium-radium balance coefficient is explored, and the correlation between the balance coefficient and uranium content and sample depth is statistically analyzed, and the determination of uranium-radium balance coefficient in the deposit is made.展开更多
In recent years,the close relationship between uranium and Ti-Fe oxides in the sandstonetype uranium deposits has been extensively recognized.However,the altered characteristics of ilmenite and its relationship with u...In recent years,the close relationship between uranium and Ti-Fe oxides in the sandstonetype uranium deposits has been extensively recognized.However,the altered characteristics of ilmenite and its relationship with uranium enrichment still remain unclear.With this paper based on heavymineral sorting of uranium ore selected from the Tarangaole-Nalinggou deposit in the northeastern Ordos Basin,electron probe,backscattering image,energy spectrum and scanning electron microscopy were systematically performed.The ilmenite in the sandstone can be divided into four groups,including unaltered,weakly altered,moderately altered,and strongly altered ilmenite.The alteration of ilmenite in uranium ores is notably more intense than that of the surrounding rocks.In addition,weakly,moderately,and strongly altered ilmenite associated with uranium minerals in uranium ores demonstrate that the more intensity ilmenite altered,the closer its relationship with uranium minerals is.The ilmenite has likely been somewhat altered before mineralization,and the alteration intensifies by later exposure related to an oxygencontaining fluid.The alteration mechanism comprises a process of competitive diffusion between Fe^(2+)and O_(2)-ions.In the early stage,Fe ions was mainly diffused on the particle surface.Subsequently,diffusion of O ions into the particles began to be dominate.Most of the leached iron is stripped or carried away by fluid.In an alkaline and reductive environment,the remaining iron is reduced to form the surrounding pyrite,and TiO_(2)in a form of titanium sol recrystallizes(i.e.,anatase).Backscattering images show that uranium and altered ilmenite are close in space.Coffinite is often distributed along the edges of altered ilmenite as burrs in shape.Colloidal or knitted coffinite associated with anatase is formed in the voids of altered ilmenite.The chemical composition of altered ilmenite varies considerably from the core to edge,and the mineral assemblage sequence is from girdle with ilmenite,to leucosphenite,to anatase,and to coffinite.There is no brannerite that is symbiotic with altered ilmenite.It is considered to be a uranium-containing titanium mineral aggregate caused by the reduction and adsorption of uranium.As the altered product of ilmenite,TiO_(2)is an aggregation agent,increasing the concentration of uranium by adsorption.Together with Fe^(2+)and S_(2)-in secondary pyrite,this aggregate creates a uranium-rich environment in the microzone for the formation of coffinite.Therefore,the alteration of ilmenite plays a geochemical role in the processes of sedimentary,diagenesis and mineralization,in which Fe is removed,Ti is enriched,and U is adsorbed and reduced.展开更多
基金supported by the National Natural Science Foundation of China(41902310,42372348,42372286)Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(2024ZD1003607)+2 种基金China Geological Survey Projects(DD20230700802,DD20221819)the Basic Research Fund of the Chinese Academy of Geological Sciences(JKYQN202306)Key Research and Development Program of Shanxi Province,China(202102090301009).
文摘The Mianhuakeng uranium deposit,characterized by uranium-rich granite,serves as a key site for research into crustal radioactive heating.Based on 45 rock samples,this study reviews that the host granite in the Mianhuakeng uranium deposit has a high radioactive heat production rate(avg.5.50μW/m³)and a low Th/U ratio(avg.2.62).Uranium-rich granite and its alteration zone within the upper crust(0-5 km depth)contribute about 45%of the total radioactive heat production,wich is crucial for controlling geothermal resource distribution.For uranium-thermal at tectonic plate margins,a symbiotic geological model was proposed:Firstly,subduction of the Pacific Plate caused upwelling of the asthenosphere,generating a high heat-flow background.Secondly,heat transfer is enhanced by major faults such as the Youdong and Mianhuakeng faults.Subsequently,uranium was mobilized,transported,and enriched within the granite through deep siliceous hydrothermal activity and associated alteration.Ultimately,the uranium enrichment in granite leads to increased radioactive heat production,resulting in local thermal anomalies.This model provides a theoretical support for exploring and developing uranium-thermal symbiotic resources in South China.
基金supported by the National Natural Science Foundation of China(No.52403035)the Shanghai Sailing Program(23YF1400300)+1 种基金the Fundamental Research Funds for the Central Universities(2232023D-05)the Weiqiao Teaching and Research Innovation Program.
文摘The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness.
基金supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2020261)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA02010000)the Young Potential Program of the Shanghai Institute of Applied Physics,Chinese Academy of Sciences(No.SINAP-YXJH-202412)。
文摘Knowing the precise relationship between fuel loading and reactivity is essential for guiding reactor criticality extrapolation and online refueling in molten salt reactors(MSRs).This study aims to explore and explain the linear relationship between reactivity and the reciprocal of uranium concentration in thermal-spectrum MSRs.By applying neutron balance theory,we analyzed the neutron absorption cross sections of various nuclides in single-lattice models with varying fuel concentrations.Our findings reveal a simple linear correlation between reactivity and the reciprocal of uranium concentration,which can be explained from the perspective of nuclear reaction cross sections that adhere to the 1/v law in the thermal neutron spectrum.Furthermore,we identified that the neutron absorption single-group cross sections of structural materials and carrier salts exhibit an approximately linear relationship with the fission single-group cross section of ^(235) U;similarly,the reciprocal of ^(235)U’s fission cross section exhibits an approximately linear relationship with uranium concentration.This linear relationship deviates as the volume fraction of molten salt increases,due to a greater proportion of neutrons being captured in the resonance energy spectrum.However,it remains valid for molten salt volume fractions up to 25%and demonstrates broad applicability in the physical design and operation of thermal molten salt reactors.
基金supported by Doctoral Scientific Fund Project of Southwest University of Science and Technology(20zx7130)Seawater Uranium Extraction Innovation and Development Fund Project(China National Nuclear Corporation)(CNNCCXLM-202215)。
文摘Many adsorbents have been developed for uranium recovery to ensure global energy and environmental security.However,most reported adsorbents involve complex preparation process and rely heavily on petrochemical feedstocks,which undoubtedly increases carbon emissions from production in the nuclear industry.Here,a biomass aerogel(CS-BT)is prepared by the facile cross-linking of chitosan and bayberry tannins with glutaraldehyde.U(Ⅵ)can be adsorbed by hydroxyl groups on CS-BT aerogel via chelation,and the maximum adsorption capacity of the obtained aerogel to U(Ⅵ)is 140 mg·g^(-1)and the removal rate reaches up to 99%(at 298.15 K,pH=5.0).The pseudo-second-order kinetics model and Freundlich model can better match the adsorption process of CS-BT aerogel,implying that its adsorption is a chemical adsorption process dominated by multilayer adsorption.The thermodynamic results show that the adsorption process of U(Ⅵ)by CS-BT aerogel is spontaneous and exothermic.Hence,our biomass aerogel can effectively extract uranium from water,contributing to the sustainable development of the nuclear industry.
基金the Young Elite Scientists Sponsorship Program by JXAST(2024QT11)the National Natural Science Foundation of China(22465001,22309003)the Jiangxi Provincial Natural Science Foundation(20232BAB203042,20242BAB22002).
文摘As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term uranium supply but is challenged by ultra-low uranium concentrations and ion interference.To overcome these issues,we design three diketopyrrolopyrrole-based covalent organic frameworks(COFs)via a synergisticπ-extended lock and carboxyl-functionalized anchor molecular engineering strategy.Among them,TPy-DPP-COF features a covalently lockedπ-conjugated structure that enhances planarity,optimizes energy alignment,and minimizes exciton binding energy,thereby promoting charge transfer and suppressing recombination.Concurrently,carboxyl groups enable uranyl-specific coordination and create local electric fields to facilitate charge separation.These features contribute to the outstanding performance of TPy-DPP-COF,which achieves a high uranium adsorption capacity of 16.33 mg g−1 in natural seawater under irradiation,with only 29.3%capacity loss after 10 cycles,surpassing industrial benchmarks.Density functional theory(DFT)calculations and experimental studies reveal a synergistic photocatalysis-adsorption pathway,with DPP units acting as active sites for uranium reduction.This work highlights a molecular design strategy for developing efficient COF-based photocatalysts for practical marine uranium recovery.
文摘One of the main issues in designing optimum tapered cascades for uranium enrichment for annual fuel production in a power reactor is whether to employ large(fat)or small(thin)cascades.What will be the permissible and optimal ranges of the number of machines that can be used in a cascade?For the first time,the permissible and optimal ranges of the number of gas centrifuges that can be utilized in a cascade were investigated using two types of centrifuges,and the performance of small and large tapered cascades was discussed.The particle swarm optimization algorithm(PSO)has been used to optimize tapered cascades.The results show:(1)For the first centrifuge,41 cascades(91≤n≤4897)and for the second centrifuge,49 cascades(18≤n≤3839)with small and large sizes can be used in enrichment facilities,and the best cascade for them has 530(with 23 stages)and 39(with 7 stages)centrifuges,respectively.(2)For both centrifuges,when 600≤n(number of centrifuges=n),the large cascade performance changes are relatively insignificant.(3)For both types of gas centrifuges,the annual los s of separation power in enrichment facilities is approximately 1.25%-4.82%of the total separation work required.
基金National Mineral Resource Potential Evaluation Project
文摘Uranium,as one of twenty-six kinds of important minerals in China,is strategic resource and energy mineral,which has been thoroughly investigated in the project of National Potential Evaluation of Uranium Resource.During the implementation of this project,the authors summarized the metallogenic regularity of uranium resource in China systematically,through the researches of geological characteristics of uranium resource,uranium deposits type（genetic and prediction type）,temporal and spatial distribution,and metallogenic series.Based on the investigation of present situation and progress in uranium exploration,this paper proposes the uranium deposits in China should be divided into 4 classes,9 types,21 subtypes in genetic,and 50 types in prediction;suggests to divide China into 29 uranium metallogenic belts and 20 uranium prospective area,and constructs 20uranium-polymetallic metallogenic series,through summarizing temporal and spatial distribution characteristics and metallogenic regularity of uranium deposits in China.The above research is beneficial to the comprehensive understanding of regional uranium metallogenic regularity,and will direct the uranium exploration in the future.
基金supported by the Russian Science Foundation grant number 23-27-00362,https://rscf.ru/en/project/23-27-00362/.
文摘The study aims to investigate uranium species in the sediments of the natural-technogenic system within a sludge storage facility in Russia.The relevance of this work is underscored by the need to assess the geochemical mobility of radionuclides,a critical factor for predicting their migration and environmental impact.The objective of the research was to determine the uranium species in both peat and sedimentary rock samples of the sludge storage facility and the adjacent area.Laboratory analyses included XRD,XRF analysis using synchrotron radiation,and scanning electron microscopy to study the composition and properties of minerals.The uranium species were further identified using a modified Tessier sequential extraction method.The results revealed that uranium predominantly occurs in a stable silicate-bound form(up to 80%)in sedimentary rocks,indicating minimal geochemical mobility.In contrast,in peat deposits,uranium is primarily associated with manganese and iron oxides(30–60%)as well as organic matter(5–40%),with the most mobile forms constituting less than 5%.The decrease in uranium concentration with distance from the facility was attributed to sorption onto organic matter and co-precipitation with mineral compounds,manganese and iron oxides,which serve as effective natural sorbents.The findings highlight the critical role of organic matter and metal oxides in limiting uranium migration,thus identifying them as key components in the formation of natural barriers for radionuclides.These results are crucial for assessing environmental risks associated with radioactive waste management and for developing strategies to minimize the ecological impact of sludge storages.
文摘Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata.
基金supported by the National Natural Science Foundation of China(Grant No.21968001).
文摘The discharge of effluents containing uranium(U)ions into aquatic ecosystems poses significant risks to both human health and marine organisms.This study investigated the biosorption of U(VI)ions from aqueous solutions using corncob-sodium alginate(SA)-immobilized Trichoderma aureoviride hyphal pellets.Experimental parameters,including initial solution pH,initial concentration,temperature,and contact time,were systematically examined to understand their influence on the bioadsorption process.Results showed that the corncob-SA-immobilized T.aureoviride hyphal pellets exhibited maximum uranium biosorption capacity at an initial pH of 6.23 and a contact time of 12 h.The equilibrium data aligned with the Langmuir isotherm model,with a maximum biosorption capacity of 105.60 mg/g at 301 K.Moreover,biosorption kinetics followed the pseudo-second-order kinetic model.In terms of thermodynamic parameters,the changes in Gibbs-free energy(△G°)were determined to be-4.29 kJ/mol at 301 K,the changes in enthalpy(△H°)were 46.88 kJ/mol,and the changes in entropy(△S°)was 164.98 J/(mol·K).Notably,the adsorbed U(VI)could be efficiently desorbed using Na_(2)CO_(3),with a maximum readsorption efficiency of 53.6%.Scanning electron microscopic(SEM)analysis revealed U(VI)ion binding onto the hyphal pellet surface.This study underscores the efficacy of corncob-SA-immobilized T.aureoviride hyphal pellets as a cost-effective and environmentally favorable biosorbent material for removing U(VI)from aquatic ecosystems.
基金supported by the Natural Science Foundation Program of China(42173072,41503037,U1967207)Postgraduate Innovative Cultivation Program(CDUT2023BJCX013)Uranium Resources Exploration and Exploitation Innovation Center&and Everest Scientific Research Program(CDUT).
文摘It has been shown that the age of minerals in which U±Th are a major(e.g.,uraninite,pitchblende and thorite)or minor(e.g.,monazite,xenotime)component can be calculated from the concentrations of U±Th and Pb rather than their isotopes,and such ages are referred to as chemical ages.Although equations for calculating the chemical ages have been well established and various computation programs have been reported,there is a lack of software that can not only calculate the chemical ages of individual analytical points but also provide an evaluation of the errors of individual ages as well as the whole dataset.In this paper,we develop a software for calculating and assessing the chemical ages of uranium minerals(CAUM),an open-source Python-based program with a friendly Graphical User Interface(GUI).Electron probe microanalysis(EPMA)data of uranium minerals are first imported from Excel files and used to calculate the chemical ages and associated errors of individual analytical points.The age data are then visualized to aid evaluating if the dataset comprises one or multiple populations and whether or not there are meaningful correlations between the chemical ages and impurities.Actions can then be taken to evaluate the errors within individual populations and the significance of the correlations.The use of the software is demonstrated with examples from published data.
基金support from the National Natural Science Foundation of China(Nos.U24B20195,U23A20105,U2341289,22341602,22327807)was acknowledged.
文摘Fast development of nuclear power plants requires sustainable support of uranium for nuclear fuel.Uranium is the most critical radionuclide to prepare nuclear fuel.However,the extraction of low concentration of uranium in uranium ore or complex systems needs highly efficient selective binding of uranium in the presence of other competing metal ions.The excellent oxidative capacity of excited*UO_(2)^(2+)active species makes uranyl-based materials high photocatalytic performance in phototransformation of organic chemicals into high valuable products under visible light irradiation.In this mini review,the selective preconcentration of uranium through photocatalytic and electrocatalytic strategies was mainly described.The application of uranyl-based materials in photocatalytic conversion and degradation of organic pollutants was summarized.This review reports the utilization of uranium from its first step(i.e.,extraction of uranium for nuclear fuel supply)to its last additional application(i.e.,uranyl-based materials as photocatalysts in transformation and conversion of organic pollutants for environmental pollution treatment)from the viewpoint of“turning uranium wastes into treasure,from waste recycling to reutilization.”In the end of this review,the challenges and perspectives of uranium separation and catalytic properties were described.
基金supported by the National Natural Science Foundation of China(No.42374226)Jiangxi Provincial Natural Science Foundation(Nos.20232BAB201043,gpyc20240073,and 20232BCJ23006)+2 种基金Nuclear Energy Development Project(20201192-01)Fundamental Science on Radioactive Geology and Exploration Technology Laboratory(2022RGET20)National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing(ECUT)(2024QZ-TD-09)。
文摘Prompt fission neutron uranium logging(PFNUL)is an advanced method for utilizing pulsed neutron bombardment of the ore layer and a fission reaction with uranium(^(235)U)to detect the transient neutrons produced by fission and then directly measure and quantify uranium;however,the stability and lifetime performance of pulsed neutron sources are the key constraints to its rapid promotion.To address these problems,this study proposes a PFNUL technique for acquiring the time spectrum of dual-energy neutrons(epithermal and thermal neutrons)from the upper and lower detection structures and establishes a novel uranium quantification algorithm based on the ratio of epithermal and thermal neutron time windows(E/T)via a mathematical-physical modeling derivation.Through simulations on well-logging models with di erent uranium contents,the starting and stopping times of the time window(Δt)for uranium quantification in the dual-energy neutron time spectrum are determined to be 200 and 800μs,respectively.The minimum radius and height of the model wells are 60 and 120 cm,respectively,and the E/T values in the time window show an excellent linear relationship with the uranium content.The scale factor is K_(E/T)=1.92 and R^(2)=0.999,which verifies the validity of the E/T uranium quantification algorithm.In addition,experiments were carried out in the Nu series of uranium standard model wells,and the results showed that under di erent neutron source yields,the E/T-based uranium quantification method reduced the relative standard deviation of the scale factor of the uranium content from 33.41%to 1.09%,compared with a single epithermal neutron quantification method.These results prove that the E/T value uranium quantification method is una ected by the change in the neutron source yield,e ectively improves the accuracy and service life of the logging instrument,and has great scientific and popularization value.
基金funded by the project initiated by the China Geological Survey“Investigation of sandstone-type uranium deposits in the Ordos and Qaidam Basins”(No.DD20190119)the National Key Research and Development Project(No.2018YFC0604200)from the Ministry of Science and Technology of the International Geoscience Programme(No.IGCP675),which is a joint endeavor of UNESCO and IUGS。
文摘The Erlian Basin is one of the most important multi-energy basins in China.The Baiyanhua area of the Chuanjing depression in the western Erlian Basin has recently become a favorable area for new progress in sandstone-type uranium prospecting.However,the Cretaceous source-to-sink evolution of the Chuanjing depression in the Erlian Basin is poorly known.This paper presents the systematic geochemical and zircon U-Pb studies on the Saihantala Formation and Erlian Formation in the Baiyanhua area.The data obtained are functionally important for revealing the provenance and tectonic setting of the source rocks.The results show that the upper part of the Saihantala Formation and the lower part of the Erlian Formation are mainly composed of felsic sedimentary rocks.The source rocks originated from a continental margin arc environment in terms of tectonic setting.The detrital zircons ages have the dominant populations at ca.250-270 Ma,with two subdominant age groups at ca.1400-1800 and 1900-2100 Ma,respectively.Combined with the tectono-sedimentary evolution of the Chuanjing depression,we conclude that:(1)the provenance of the Cretaceous strata was mostly sourced from the Baiyanhua uplift;(2)the water depth became shallow in the Southern Sangendalai sag during the middle period of Saihantala,further preventing the formation of coal beds;(3)the formation of Baiyanhua uplift might provide the beneficial tectonic condition for uranium mineralization in the upper Saihantala Formation in southern Sangendalai sag.This is significant for us to understand the space allocation of coal and uranium in Chuanjing depression and evaluate the uranium metallogenic prospects in southern Sangendalai sag.
基金supported by the National Natural Science Foundation of China(No.82160627)the Natural Science Foundation of the Guangxi Autonomous Region(No.2020GXNFSAA297262)。
文摘Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8 assay. Apoptosis was measured using flow cytometry. Reagent kits were used to detect carbonyl stress markers malondialdehyde, 4-hydroxynonenal, thiobarbituric acid reactive substances, and protein carbonylation. Aldehyde-protein adduct formation and alcohol dehydrogenase, aldehyde dehydrogenase 2, aldo-keto reductase, nuclear factor E2-related factor 2(Nrf2), and cystathionine β-synthase(CBS) expression were determined using western blotting or real-time PCR. Sulforaphane(SFP) was used to activate Nrf2. RNA interference was used to inhibit CBS expression.Results GYY4137(an H_(2)S donor) pretreatment significantly reversed the uranium-induced increase in carbonyl stress markers and aldehyde-protein adducts. GYY4137 effectively restored the uraniumdecreased Nrf2 expression, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2, accompanied by a reversal of the uranium-decreased expression of CBS and aldehyde-metabolizing enzymes. The application of CBS siRNA efficiently abrogated the SFP-enhanced effects on the expression of CBS, Nrf2 activation, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2 and concomitantly reversed the SFP-enhanced effects of the uranium-induced mRNA expression of aldehyde-metabolizing enzymes.Simultaneously, CBS siRNA reversed the SFP-mediated alleviation of the uranium-induced increase in reactive aldehyde levels, apoptosis rates, and uranium-induced cell viability.Conclusion H_(2)S induces Nrf2 activation and nuclear translocation, which modulates the expression of aldehyde-metabolizing enzymes and the CBS/H_(2)S axis. Simultaneously, the Nrf2-controlled CBS/H_(2)S axis may at least partially promote Nrf2 activation and nuclear translocation. These events form a cycleregulating mode through which H_(2)S attenuates the carbonyl stress-mediated NRK-52E cytotoxicity triggered by uranium.
基金supported by the National Natural Science Foundation of China(Nos.12175170 and 11675066)。
文摘The study of uranium isotopes plays a crucial role in advancing our knowledge of nuclear physics,particularly in the realm of isospin and exotic nuclei.This study focused on the ground-state properties of uranium isotopes ranging from A=203 to A=305.The key physical quantities examined included binding energy,quadrupole deformation,isotopic displacement,single-particle energy levels,and nucleon density distributions.Recent experimental advancements in uranium isotope studies have emphasized the indispensable role of theoretical models in interpreting experimental data.Moreover,the industrial applications of uranium—especially in nuclear energy production and weapons development—underscore the importance and necessity of accurate theoretical insights.The framework of the finite-range droplet model(FRDM)was utilized for comparative analysis because its predictions closely align with the experimental results.Through an analysis of the single-particle energy levels and continuous-state occupancy,this study identified 207 U as the proton drip line nucleus.This research not only deepens our understanding of uranium isotopes but also provides a solid theoretical foundation to guide future experimental investigations.
基金financially supported by the National Natural Science Foundation of China(Nos.22366004 and 42302293)the National Key Laboratory of Uranium Resources Exploration-Mining and Nuclear Remote Sensing Independent Project(No.2024QZ-TD-19)+2 种基金the Key R&D Plan of Jiangxi Province(No.20212BBG71011)China Uranium Corporation Limited-East China University of Technology State Key Laboratory of Nuclear Resources and Environment Joint Innovation Fund(No.2023NRE-LH-19)the Innovation Special Fund Project of Graduate Student in East China University of Technology(No.DHYC-202414)
文摘Urchin-like W_(18)O_(49),with a large specific surface area(113.738 m^(2)g^(-1))and abundant oxygen vacancies(OVs),was prepared using an active sites tuning and microstructure engineering method.This material was applied for U(Ⅵ)adsorption for the first time,demonstrating a high adsorption capacity of 567.55 mg g^(-1),which exceeds that of most inorganic adsorbents.Characterization via active site masking experiments and theoretical calculations,etc.,indicated that the excellent adsorption performance toward U(Ⅵ)was due to strong complexation between UO_(2)^(2+)and W–O bond of W_(18)O_(49),facile oxygen vacancy adsorption,and interface electron transfer from W^(5+)to UO_(2)^(2+),which acted as a reducing agent,partially converting U(Ⅵ)to U(IV).Furthermore,W_(18)O_(49)exhibited practical applicability with a removal rate exceeding 82%after 5 cycles,a 92.79%removal rate for real uranium-containing wastewater,and a high uranium recovery rate of 75.96%.Additionally,the synergistic adsorption-photocatalytic effect significantly enhanced U(Ⅵ)extraction,reaching an extraction capacity of 988.0mg g^(-1).This work provides a promising strategy for developing highly efficient U(Ⅵ)WO_(3)-based adsorbents.
基金financially supported by projects from the National Natural Science Foundation of China(No.42321001)the Qinghai Provincial Department of Science and Technology Key R&D Project(No.2025-SF-141)+1 种基金the Qinghai“Kunlun Talent”Program(Qing RC Talent Zi(2024)No.1)the Academician Zhao Pengda Innovation Center in Qinghai Geological Bureau of Nuclear Industry。
文摘0 INTRODUCTION The Haidewula uranium deposit is located in the Haidewula volcanic basin,which hosts a suite of basic,intermediate to felsic volcanic and subvolcanic rocks,including basalt,trachyte,trachyandesite.Previous geochronological studies of the intrusions within this volcanic basin suggest that they primarily formed during the Silurian and Triassic periods(Dai et al.,2025;Sun et al.,2024;Wang et al.,2024;Zhu et al.,2022;Lei et al.,2021).
文摘The former uranium ore logging data are mainly used for lithologic identification, stratigraphic division, shale content estimation, preliminary determination of sedimentary environment, accurate determination of spatial location, grade, thickness of uranium ore bodies, and determination of casing installation and cementing quality. Uranium-radium balance coefficient is one of the important parameters in uranium exploration, which is of great significance in guiding uranium exploration and studying uranium mineralization law. In this paper, the frequency change of uranium-radium balance coefficient is explored, and the correlation between the balance coefficient and uranium content and sample depth is statistically analyzed, and the determination of uranium-radium balance coefficient in the deposit is made.
基金financially supported by projects under the National Key Research and Development Program of China(No.2018YFC0604200)the Open Fund Project of State Key Laboratory of Nuclear Resources and Environment (No.2020NRE10)+3 种基金the National Key Infrastructure Development Plan (No.2015CB453006)the China Geological Survey (Nos.DD20190119,DD20221678)the International Geoscience Programme (No.IGCP-675)the National Nature Science Foundation of China (No.92162212)
文摘In recent years,the close relationship between uranium and Ti-Fe oxides in the sandstonetype uranium deposits has been extensively recognized.However,the altered characteristics of ilmenite and its relationship with uranium enrichment still remain unclear.With this paper based on heavymineral sorting of uranium ore selected from the Tarangaole-Nalinggou deposit in the northeastern Ordos Basin,electron probe,backscattering image,energy spectrum and scanning electron microscopy were systematically performed.The ilmenite in the sandstone can be divided into four groups,including unaltered,weakly altered,moderately altered,and strongly altered ilmenite.The alteration of ilmenite in uranium ores is notably more intense than that of the surrounding rocks.In addition,weakly,moderately,and strongly altered ilmenite associated with uranium minerals in uranium ores demonstrate that the more intensity ilmenite altered,the closer its relationship with uranium minerals is.The ilmenite has likely been somewhat altered before mineralization,and the alteration intensifies by later exposure related to an oxygencontaining fluid.The alteration mechanism comprises a process of competitive diffusion between Fe^(2+)and O_(2)-ions.In the early stage,Fe ions was mainly diffused on the particle surface.Subsequently,diffusion of O ions into the particles began to be dominate.Most of the leached iron is stripped or carried away by fluid.In an alkaline and reductive environment,the remaining iron is reduced to form the surrounding pyrite,and TiO_(2)in a form of titanium sol recrystallizes(i.e.,anatase).Backscattering images show that uranium and altered ilmenite are close in space.Coffinite is often distributed along the edges of altered ilmenite as burrs in shape.Colloidal or knitted coffinite associated with anatase is formed in the voids of altered ilmenite.The chemical composition of altered ilmenite varies considerably from the core to edge,and the mineral assemblage sequence is from girdle with ilmenite,to leucosphenite,to anatase,and to coffinite.There is no brannerite that is symbiotic with altered ilmenite.It is considered to be a uranium-containing titanium mineral aggregate caused by the reduction and adsorption of uranium.As the altered product of ilmenite,TiO_(2)is an aggregation agent,increasing the concentration of uranium by adsorption.Together with Fe^(2+)and S_(2)-in secondary pyrite,this aggregate creates a uranium-rich environment in the microzone for the formation of coffinite.Therefore,the alteration of ilmenite plays a geochemical role in the processes of sedimentary,diagenesis and mineralization,in which Fe is removed,Ti is enriched,and U is adsorbed and reduced.
