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Genesis Mechanism of Heat Source in Mianhuakeng Uranium Deposit,South China:Insights from Radiogenic Heat Production of Granite Bodies
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作者 WANG Siqi ZHANG Baojian +2 位作者 LÜGuosen LIU Feng ZHU Xi 《Acta Geologica Sinica(English Edition)》 2026年第1期286-296,共11页
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
关键词 uranium-rich granite radiogenic heat production heat source genesis mechanism Mianhuakeng uranium deposit
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
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
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS uranium extraction
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Linear relationship between reactivity and the reciprocal of uranium concentration in thermal-spectrum molten salt re
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作者 Chang-Qing Yu Gui-Feng Zhu +7 位作者 Shu-Yang Jia Yang Zou Rui Yan Jian Guo Ya-Fen Liu Bo Zhou Xue-Chao Zhao Xiao-Han Yu 《Nuclear Science and Techniques》 2026年第2期208-222,共15页
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
关键词 Molten salt reactor REACTIVITY uranium concentration Cross sections LINEAR
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Cutting-edge aminated conjugated microporous poly(aniline)s enabled high-performance membrane for seawater uranium extraction
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作者 Xiaoxia Ye Bingqing Huang +7 位作者 Xueying Chen Yaping Wang Zhihong Zheng Yifan Liu Yuancai Lv Chunxiang Lin Jian Huang Jie Chen 《Green Energy & Environment》 2026年第1期181-194,共14页
The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by th... The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by the longstanding challenge of identifying sustainable membrane materials.In response,we propose a prototypal hybridization strategy to design a novel series of aminated conjugated microporous polymer(CMPN)@collagen fiber membrane(COLM).These sustainable and low-cost membrane materials allow a rapid and high-affinity kinetic to capture 90%of the uranium in just 30 min from 50 ppm with a high selectivity of Kd>105 mL·g^(−1).They also afford a robustly reusable adsorption capacity as high as 345 mg·g^(−1)that could harvest 1.61 mg·g^(−1)of uranium in a short 7-day real marine engineering in Fujian Province,even though suffered from very low uranium concentration of 3.29μg·L^(−1)and tough influence of salts such as 10.77 g·L^(−1)of Na^(+),1.75μg·L^(−1)of VO_(3)^(−)etc.in the rough seas.The structural evidence from both experimental and theoretical studies confirmed the formation of favorable chelating motifs from the amino group on CMPN-COLM,and the intensification by the synergistic effect from the size-sieving action of CMPN and the capillary inflow effect of COLM. 展开更多
关键词 Conjugated microporous polymer Collagen fiber MEMBRANE Seawater uranium extraction
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Biomass aerogel based on chitosan and bayberry tannin for uranium recovery from aqueous solution
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作者 Gui-Qiang He Jin-Fan Ou +3 位作者 Yan-Xia Wei Ai-Xia Lu Dan Lin Jian Zhou 《Nuclear Science and Techniques》 2026年第3期79-89,共11页
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
关键词 Biomass aerogel CHITOSAN Bayberry tannin uranium recovery
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Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction
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作者 Fengtao Yu Xiaolong Zhang +5 位作者 Jie Xu Guihong Wu Huiying Lei Zhiwu Yu Jianding Qiu Jianli Hua 《Journal of Energy Chemistry》 2026年第1期284-293,I0007,共11页
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
关键词 DIKETOPYRROLOPYRROLE Covalent organic frameworks Exciton binding energy Photocatalytic uranium extraction Synergistic effect
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Comparing of small and large optimal tapered cascades for supplying enriched uranium for fresh fuel production in the equilibrium cycle of a nuclear power reactor
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作者 S.L.Mirmohammadi J.Safdari A.A.Ghorbanpour Khamseh 《Nuclear Science and Techniques》 2026年第3期208-234,共27页
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
关键词 Small tapered cascade(thin) Large tapered cascade(fat) Enriched uranium fuel Power reactor PSO algorithm
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From bench to buoy:challenges in seawater uranium extraction
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作者 Zhenli Sun Hanyang Wang +5 位作者 Zhongshan Chen Xishi Tai Jiehong Lei Baowei Hu Suhua Wang Xiangke Wang 《Science China Materials》 2026年第3期1416-1419,共4页
Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear ... Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear power plants in a few years.Uranium-235 serves as the primary fissile material for the fabrication of nuclear fuel.However,there are only about 6.14 million tons of uranium resources on land,which can sustain~70 years of operation for global nuclear power plants.Thereby,the recovery of uranium from spent fuel,radioactive waste solutions,seawater,and salt lakes is crucial for the healthy development of nuclear power utilization[2-4]. 展开更多
关键词 carbon neutrality china nuclear power plantstherebythe peaking carbon dioxide emissions sustainable economic development fissile material nuclear energy seawater uranium extraction nuclear power plants
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Outline of Uranium Resources Characteristics and Metallogenetic Regularity in China 被引量:15
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作者 CAI Yuqi ZHANG Jindai +6 位作者 LI Ziying GUO Qingyin SONG Jiye FAN Honghai LIU Wusheng QI Fucheng ZHANG Minglin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第3期918-937,共20页
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
关键词 uranium deposit uranium deposit type uranium metallogenic regularity uraniummetallogenic belt uranium metallogenic series
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Uranium Species in Peat and Rock Sediments Near Sludge Storage Facility
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作者 Olga Shvartseva Daria Mashkova 《Journal of Environmental & Earth Sciences》 2025年第2期187-197,共11页
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
关键词 uranium Sludge Storage Mineral Composition uranium Speciation in Sediments Sorption by Peat XRD SEM Safe Management
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Uranium Provinces in China 被引量:7
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作者 CHEN Zhaobo ZHAO Fengmin +1 位作者 XIANG Weidong CHEN Yuehui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期587-594,共8页
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
关键词 uranium province Phanerozoic hydrothermal(vein-type)uranium deposit Meso-Cenozoic sandstone-type uranium deposit genesis of uranium province
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Trichoderma aureoviride hyphal pellets embedded in corncob-sodium alginate matrix for efficient uranium(Ⅵ)biosorption from aqueous solutions
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作者 Min Li Bo Liang +3 位作者 Jie-ming Liu Jin Zhang Bin Wang Jie Shang 《Water Science and Engineering》 2025年第1期51-58,共8页
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
关键词 BIOSORPTION uranium Trichoderma aureoviride Immobilization CORNCOB
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CAUM:A software for calculating and assessing chemical ages of uranium minerals
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作者 Hao Song Tao Xiao +3 位作者 Guoxiang Chi Zexin Wang Zhengqi Xu Mingcai Hou 《Geoscience Frontiers》 2025年第3期183-192,共10页
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
关键词 Chemical ages uranium minerals EPMAU-Th-Pb geochronology SOFTWARE Python
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Recent Progress of Uranium Extraction and its Catalytic Applications
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作者 Guo Wei Zhongshan Chen +2 位作者 Xishi Tai Zhenli Sun Xiangke Wang 《Transactions of Tianjin University》 2025年第4期390-402,共13页
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
关键词 uranium High selective extraction Photocatalytic property CONVERSION TRANSFORMATION
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Prompt fission neutron uranium logging(Ⅰ):direct uranium quantification method theory
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作者 Yan Zhang Chi Liu +6 位作者 Hai-Tao Wang Xiong-Jie Zhang Zhi-Feng Liu Rui Chen Jin-Hui Qu Ren-Bo Wang Bin Tang 《Nuclear Science and Techniques》 2025年第6期216-227,共12页
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
关键词 PFNUL uranium exploration Pulsed neutrons Neutron time spectrum
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Geochemistry and Detrital Zircon U-Pb Chronology of Late Mesozoic Strata in the Western Erlian Basin and Their Indication to Provenance and Uranium Metallization
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作者 Reng-An Yu Tong Li +4 位作者 Qiang Zhu Qinghong Si Jiarun Tu Shenglong Peng Yongxiang Tang 《Journal of Earth Science》 2025年第5期2058-2074,共17页
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
关键词 Erlian Basin Saihantala Formation detrital zircon U-Pb geochronology PROVENANCE sandstone type uranium metallization GEOCHEMISTRY mineral doposits
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Organic ion building blocks-assembled carboxyl ionic single crystals for ultra-selective and ultrafast uranium extraction
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作者 Jing He Jia Chen +5 位作者 Yongxing Sun Zijie Li Huifeng Liu Juanjuan Wang Weiqun Shi Hongdeng Qiu 《Nano Research》 2025年第12期531-541,共11页
Uranium extraction from seawater(UES)is crucial for reducing nuclear fuel supply pressure and promoting the comprehensive utilization of marine resources.The successful implementations of UES engineering critically re... Uranium extraction from seawater(UES)is crucial for reducing nuclear fuel supply pressure and promoting the comprehensive utilization of marine resources.The successful implementations of UES engineering critically rely on the highly efficient sorbent materials with exceptional performance in binding uranyl ions.Herein,a universal and facile“organic ion building blocks self-assembly”strategy is established to realize a first class of carboxyl functionalized ionic single crystals,named BPTC-BPY-R(R=1–6,the R corresponds to alkyl chain length modifier,e.g.,R=1 corresponds to iodomethane derivatives,R=2 corresponds to bromoethane derivatives,etc.),derived from rationally designed viologen-derivatives with different alkyl chain lengths and polycarboxylic acid.This strategy effectively exploits the organic ion building block properties to achieve U(VI)adsorption based on the synergistic effects of anions(ligand interaction)and cations(electrostatic interaction).Notably,attributed to the special crystal stacking mode and higher specific surface area,the resulting BPTC-BPY-3 not only achieves ultrahigh selectivity for U(VI)adsorption with a partition coefficient of 3.998×10^(6) mL/g,but also possesses an ultrafast U(VI)adsorption kinetics and an uptake capacity of 686.8 mg/g within 2 min.More importantly,it realizes a U(VI)uptake capacity of 7.41 mg/g from natural seawater in 20 days.The designed material with ultra-selectivity,high capacity,ultrafast kinetics,and good recyclability exhibits a great promise for efficient U(VI)extraction from seawater. 展开更多
关键词 ionic self-assembly single crystal uranium extraction organic ion building block chain length tuning
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Hydrogen Sulfide Alleviates Lipid Peroxidation-Mediated Carbonyl Stress in Uranium-Intoxicated Kidney Cells via Nrf2/ARE Signaling
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作者 Jialin Liu Min Wang +3 位作者 Rui Zhang Jifang Zheng Xixiu Jiang Qiaoni Hu 《Biomedical and Environmental Sciences》 2025年第4期484-500,共17页
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
关键词 Hydrogen sulfide(H_(2)S) Carbonyl stress Lipid peroxidation uranium NEPHROTOXICITY NRF2
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Ground-state properties of uranium isotope chain:a relativistic mean field approach
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作者 Di Xu Hong-Fei Zhang 《Nuclear Science and Techniques》 2025年第9期199-208,共10页
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
关键词 Relativistic mean field BCS theory uranium isotopic chain
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Discovery and Significance of Paleozoic Granite Porphyry in the Haidewula Uranium Deposit,East Kunlun Orogenic Belt,Northwest China
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作者 Jian-Hua Duan Tong Liu +3 位作者 Jia-Wen Dai Hui-Min Su Yan-Qiang Li Shao-Yong Jiang 《Journal of Earth Science》 2025年第5期2365-2372,共8页
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
关键词 geochronological studies PALEOZOIC subvolcanic rocksincluding silurian triassic periods dai east kunlun orogenic belt volcanic basin granite porphyry haidewula uranium deposit
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