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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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Ultra-fast uranium adsorption with phosphorylated tungsten disulfide nanosheets via sulfur defects
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作者 Yuan-Ping Jiang Guo-Hang He +12 位作者 Jin-Cao Chen Jia-Rui Zhou Xing-Fang Yu Long-Xu Wang Xin Zeng Jiang-Chen Liu Jia-Jian Yang Chong Lin Xiao-Yu Hao Zuo-Jia Li Yun-Xiu Zhang Zhi-Bin Zhang Yun-Hai Liu 《Tungsten》 2025年第4期876-886,共11页
Rapid adsorption of radioactive substances is of great significance in emergency situations.A novel approach combining S-defect introduction and in situ phosphorization was employed to synthesize phosphorized WS_(2)(W... Rapid adsorption of radioactive substances is of great significance in emergency situations.A novel approach combining S-defect introduction and in situ phosphorization was employed to synthesize phosphorized WS_(2)(WS_(2)-PO_(4))for ultra-efficient uranium extraction.At an initial U(VI)concentration of 50 mg·L^(-1),the adsorption of U(VI)by WS_(2)-PO_(4) nanosheets exceeds77%within just 1 min,with high selectivity(SU=78.7%)and good adsorption capacity of 268.82 mg·g^(-1).The phosphate groups have grown on the S defects and taken part in U(VI)extraction through surface complexation,leading to fast,reusable,and highly selective uranium adsorption,showing great potential in emergency treatment of radioactive nuclear wastewater. 展开更多
关键词 TUNGSTEN PHOSPHORYLATION uranium DEFECTS ADSORPTION
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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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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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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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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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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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Highly efficient capture of uranium(Ⅵ)from wastewater by urchin-like W_(18)O_(49):insights to performance-dependence on active sites
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作者 Chao-Long Liu Keng Xuan +6 位作者 Yao-Ping Guo Hao Jiang Wen-Jie Ma Xue-Gang Wang Zhong-Kui Zhou Jun Li Ya-Dan Guo 《Rare Metals》 2025年第9期6786-6800,共15页
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
关键词 Adsorption uranium(VI) W_(18)O_(49) Oxygen vacancy Active sites
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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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酸性铀污染地下水原位生物修复技术:进展与挑战
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作者 刘亚洁 李江 +2 位作者 王学刚 柯平超 孙占学 《地学前缘》 北大核心 2026年第1期250-268,共19页
酸性铀污染地下水是全球亟待解决的重大环境问题。原位生物修复因其经济性与可持续性等优势,成为极具潜力的治理策略。本文系统解析酸性铀污染地下水原位生物修复的技术原理、现存问题与发展方向:追溯铀采冶活动引发的酸性污染成因,阐... 酸性铀污染地下水是全球亟待解决的重大环境问题。原位生物修复因其经济性与可持续性等优势,成为极具潜力的治理策略。本文系统解析酸性铀污染地下水原位生物修复的技术原理、现存问题与发展方向:追溯铀采冶活动引发的酸性污染成因,阐释金属还原微生物作用的代谢特征及原位修复技术发展历程,评述生物还原(核心)、生物矿化(稳定固化)、生物吸附(快速截留)和生物累积(资源化潜力)等多元固铀机制;剖析极端酸性环境(pH<4.0)、竞争性电子受体(硝酸盐等)、寡营养环境、微生物群落动态演替及U(Ⅳ)产物稳定性等关键制约因素,提出针对性解决策略;未来应以自主适应微生物群落构建、稳定性强化技术(如晶态U(Ⅳ)生成调控)与多机制协同融合(生物-化学耦合、电子供体智能投送等)的创新研究为方向,以提升复杂酸性系统中修复效能与长效性。 展开更多
关键词 铀污染 酸性地下水 原位生物修复 铀固化机制 挑战
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基于自然伽马能谱的三参数页岩黏土矿物含量计算模型——以四川盆地龙马溪组页岩为例
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作者 任文希 朱思融 +2 位作者 卢聪 姜淑贤 陈新意 《断块油气田》 北大核心 2026年第1期67-73,共7页
黏土矿物含量是评价页岩储层的重要参数之一。文中从岩石物理学出发,选择了自然伽马能谱测井中可以有效反映黏土矿物含量的无U伽马值,建立了针对黏土矿物的一个指示参数,进一步结合页岩气常规测井系列,建立了针对黏土矿物的另一个指示参... 黏土矿物含量是评价页岩储层的重要参数之一。文中从岩石物理学出发,选择了自然伽马能谱测井中可以有效反映黏土矿物含量的无U伽马值,建立了针对黏土矿物的一个指示参数,进一步结合页岩气常规测井系列,建立了针对黏土矿物的另一个指示参数,然后通过主成分分析和多元线性回归,建立了无需识别基线的页岩黏土矿物含量计算模型。基于龙马溪组页岩测井资料和实验数据,对新建立的模型进行了测试。结果显示:新建立的模型精度较高,优于传统的中子-密度归一化差值模型和无U伽马模型,也优于支持向量机和随机森林这2种机器学习模型,具有一定的推广价值。 展开更多
关键词 页岩 黏土矿物含量计算 测井 自然伽马能谱测井 无U伽马
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准噶尔盆地中北部蚀源区岩浆岩时空分布特征与 铀源 条件分析
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作者 曹玉召 吴玉 +8 位作者 钟军 朱斌 韩长城 马静辉 林陈雨 何中波 冀华丽 东前 郭子欣 《地学前缘》 北大核心 2026年第2期290-310,共21页
蚀源区铀源的分析和评价对沉积盆地中砂岩型铀矿的勘查具有重要意义。本研究聚焦于准噶尔盆地中北部地区,通过对蚀源区岩浆岩的铀含量特征、锆石U-Pb年龄分布和Hf同位素组成特征分析,探讨蚀源区岩浆岩时空分布特征、铀源条件以及有利铀... 蚀源区铀源的分析和评价对沉积盆地中砂岩型铀矿的勘查具有重要意义。本研究聚焦于准噶尔盆地中北部地区,通过对蚀源区岩浆岩的铀含量特征、锆石U-Pb年龄分布和Hf同位素组成特征分析,探讨蚀源区岩浆岩时空分布特征、铀源条件以及有利铀源的岩浆岩特征,进而为准噶尔盆地中北部砂岩型铀矿找矿预测提供了源区评价依据。分析结果表明,准噶尔盆地中北部蚀源区富铀地质体的岩浆活动期次主要集中在奥陶纪、晚志留世—晚泥盆世和早石炭世—晚二叠世,其次为早侏罗世。在空间分布上,蚀源区富铀地质体的铀含量和供铀能力呈现出“自北向南减小、东高西低”的趋势。阿尔泰造山带中段和东准噶尔的野马泉岛弧带具有较高的供铀能力,而西准噶尔造山带的铀含量相对较低。在岩浆岩类型上,蚀源区古铀含量最高和供铀能力最强的岩体为酸性侵入岩,其次为碱性岩和酸性喷出岩,最后是中基性岩浆岩;在岩石成因上,S型的花岗岩较A型和I型花岗岩具有更好的铀源条件;另外,锆石Hf同位素特征显示,壳源岩浆岩相较于幔源岩浆岩更为富铀。因此,多种因素的叠加促使了有利铀源的形成。最后,根据有利铀源的分布和盆地内已知铀矿化信息,提出准噶尔盆地东部卡姆斯特地区、库普盆地西北缘、福津盆地北部以及和什托洛盖盆地北部具有较好的砂岩型铀矿的成矿潜力。 展开更多
关键词 古铀含量 蚀源区岩浆岩 铀源条件 砂岩型铀矿 准噶尔盆地中北部地区
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地震氡测量仪便携校准装置研制与测试分析
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作者 田兴宇 张雄杰 +3 位作者 刘佳悦 李文一 明晓冉 王忠彪 《核电子学与探测技术》 北大核心 2026年第1期80-87,共8页
氡的准确测量是保障地震监测数据质量的关键因素,为确保测氡仪测试结果准确,需定期对其进行校准。测氡仪主要通过氡室和镭标准源进行校准,为确保地震监测数据的连贯性,各观测站的测氡仪不宜长时间脱离观测位置,难以借助氡室等大型实验... 氡的准确测量是保障地震监测数据质量的关键因素,为确保测氡仪测试结果准确,需定期对其进行校准。测氡仪主要通过氡室和镭标准源进行校准,为确保地震监测数据的连贯性,各观测站的测氡仪不宜长时间脱离观测位置,难以借助氡室等大型实验设施进行校准。同时,随着国家对放射性标准源监管日趋严格,镭生产厂商持续减少,导致由镭制成的固态氡源采购愈发困难。随着现有氡源逐步老化淘汰,各观测点配置的仪器因缺乏有效校准手段,或将导致氡观测数据准确度降低。为满足地震氡测量仪器的校准需求,本文提出采用铀矿废石压片材料制作氡源,以流气平衡控制法构建不同氡体积活度环境进行测氡仪校准的测试方法,并基于此设计了操作简单、便于携带的小型测氡仪校准装置。测试结果表明,该校准装置氡体积活度调控范围为(600~3500)Bq/m^(3),可用于提供测氡仪校准测试环境,且装置所构建校准环境也具有良好的稳定性。经实验验证,通过所研制装置取得校准结果的相对标准不确定度为6.0%,与氡室对比结果的归一化误差为0.0931,二者一致性良好,该装置初步具备应用于测氡仪周期校准测试、期间核查以及响应实验的可行性。 展开更多
关键词 测氡仪 仪器校准 铀矿废石
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退火法制备TiO_(2)/Ti电极及其对有机含铀废水的电化学净化
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作者 彭超 李天宇 +4 位作者 吕慧涛 陈佳琪 颜永得 薛云 田国新 《原子能科学技术》 北大核心 2026年第1期148-157,共10页
高温气冷堆燃料元件生产过程中会产生相当量的偏碱性含铀废水,其中还含有一定浓度的尿素、聚乙烯醇、四氢糠醇等有机物。为实现有机含铀废水的净化,本研究针对这种废水开展铀去除研究。首先通过对Ti片进行680℃退火处理,制备了TiO_(2)/T... 高温气冷堆燃料元件生产过程中会产生相当量的偏碱性含铀废水,其中还含有一定浓度的尿素、聚乙烯醇、四氢糠醇等有机物。为实现有机含铀废水的净化,本研究针对这种废水开展铀去除研究。首先通过对Ti片进行680℃退火处理,制备了TiO_(2)/Ti电极,然后配制有机含铀模拟溶液,采用电化学法开展模拟溶液中铀的去除研究,探索了碳酸根浓度、pH、铀初始浓度、时间、电压等因素对铀去除率的影响,并推测了过程的反应机理。X射线光电子谱(XPS)、扫描电子显微镜(SEM)、电子能谱(EDS)和X射线衍射(XRD)分析表明,通过退火处理合成的TiO_(2)/Ti电极表面被颗粒状金红石相TiO_(2)覆盖,说明通过退火法能成功制备TiO_(2)/Ti电极。电化学法去除模拟溶液(pH=9)中铀的最优条件为:碳酸钠浓度0.01 mol/L、电压10 V、时间5 h,此条件下铀去除率达95.43%。0.01 mol/L碳酸钠溶液中,铀的还原电位为-0.99 V(vs SCE),其还原过程为一步单电子过程,U(Ⅵ)得到1个电子还原为U(Ⅴ),再歧化为U(Ⅳ)和U(Ⅵ),铀是以UO_(2)和U_(2)O_(5)的形态沉积在电极表面。在4种共存物中,硝酸铵、尿素和聚乙烯醇对铀去除有明显的抑制,而四氢糠醇则没有明显影响。它们共同存在时,在10 V条件下,铀去除率下降至36.75%,但通过提升电压至15 V,铀去除率上升至85.99%。本文所制备TiO_(2)/Ti电极的重复利用性良好,重复使用8次后,铀去除率仍能达到90%以上,每次重复使用,铀的回收率基本能达90%以上。 展开更多
关键词 含铀废水 电化学 TiO_(2)/Ti电极 有机物
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松嫩盆地硝氮驱动的地下水铀富集机理
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作者 高志鹏 郭华明 +3 位作者 丁正 姜春平 胡学达 徐达 《水文地质工程地质》 北大核心 2026年第1期12-22,共11页
氮素污染导致的地下水重金属次生污染是当前研究的重点和热点。本研究旨在探究地下水中硝氮的分布、来源及其对地下水中铀迁移转化的控制机制。本研究综合采用水化学、NO_(3)^(-)氮氧同位素及水文地球化学模拟的方法,探究了松嫩盆地西... 氮素污染导致的地下水重金属次生污染是当前研究的重点和热点。本研究旨在探究地下水中硝氮的分布、来源及其对地下水中铀迁移转化的控制机制。本研究综合采用水化学、NO_(3)^(-)氮氧同位素及水文地球化学模拟的方法,探究了松嫩盆地西部山前倾斜平原地下水中NO_(3)^(-)来源、转化及其驱动的地下水中铀富集过程。研究区地下水沿流向逐渐由氧化环境演变至还原环境,氧化区地下水铀质量浓度(平均14.2μg/L)显著高于还原区(平均4.1μg/L);氧化区地下水NO_(3)^(-)平均质量浓度高达188 mg/L,还原区普遍低于10 mg/L。NO_(3)^(-)氮氧同位素结果表明:氧化区地下水NO_(3)^(-)主要来自土壤NH_(4)^(+)及NH_(4)^(+)氮肥的硝化作用;而在还原区则主要来自NO_(3)^(-)氮肥的输入。氧化区高浓度的NO_(3)^(-)一方面将固态U(Ⅳ)氧化为溶解态U(Ⅵ),另一方面通过驱动碳酸盐岩风化导致Ca-U-CO_(3)三元络合物的形成,进一步促进了地下水铀的富集;还原区主要发生硅酸盐岩风化及Ca^(2+)与Na^(+)离子交换过程,地下水氧化还原电位和Ca^(2+)浓度均较低,不利于地下水铀的富集。本研究对于理解地下水NO_(3)^(-)污染导致的次生铀浓度超标具有重要的理论意义。 展开更多
关键词 松嫩盆地 地下水 硝氮 富集机理
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河套盆地含水层沉积物铀赋存特征及对地下水铀富集的影响
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作者 章一川 常光明 +2 位作者 鲁重生 邢世平 郭华明 《地学前缘》 北大核心 2026年第2期535-547,共13页
长期暴露在高铀(U)地下水中会对人体健康造成潜在威胁。尽管高U地下水形成的水文地球化学过程已得到广泛研究,目前对含水层沉积物的水文地球化学特征如何控制地下水U迁移和富集仍缺乏深入理解。本文以河套盆地为研究区,采集了山前区和... 长期暴露在高铀(U)地下水中会对人体健康造成潜在威胁。尽管高U地下水形成的水文地球化学过程已得到广泛研究,目前对含水层沉积物的水文地球化学特征如何控制地下水U迁移和富集仍缺乏深入理解。本文以河套盆地为研究区,采集了山前区和平原区含水层沉积物样品并对其中U的不同赋存形态和含量进行分析。结果表明,山前区沉积物中U含量远高于平原,山前区U主要以铁锰氧化物结合态(F3-U)为主,平原区主要为基质态(F5-U)。沉积物U含量随其粒径减小呈现增大的趋势,其中黏土沉积物中U含量最高。沉积物中各赋存态U含量与Fe、Mn含量均呈正相关关系,表明Fe、Mn对沉积物中U富集有着重要控制作用。地下水中的U主要受到沉积物中可交换态(F1-U)、碳酸盐结合态(F2-U)和铁锰氧化物结合态(F3-U)这三种赋存形态的控制。在山前区,解吸附和氧化溶解作用促进地下水中U的富集;在平原区,含水层中铁锰氧化物还原溶解释放的U在还原环境中被还原为U(IV)再次固定在沉积物中,形成高Fe 2+低U的地下水。本研究将含水层沉积物地球化学特征与地下水U的迁移富集建立联系,揭示了含水层沉积物铀赋存特征对地下水U富集的影响。 展开更多
关键词 河套盆地 含水层沉积物 地下水 氧化还原过程
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共价有机框架纤维膜的制备及其海水提铀应用
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作者 胡张挺 陈乾浩 +4 位作者 叶昊 温柔铭 袁梓豪 吴铭榜 姚菊明 《浙江理工大学学报(自然科学版)》 2026年第1期1-12,共12页
为解决共价有机框架(Covalent organic frameworks,COFs)粉末在海水提铀中分离困难和传质效率低等问题,通过静电纺丝牺牲模板法与原位合成法制备自支撑COFs纤维膜(COFs fiber membrane,COFs-M)。分析COFs-M的微观形貌、比表面积、孔径... 为解决共价有机框架(Covalent organic frameworks,COFs)粉末在海水提铀中分离困难和传质效率低等问题,通过静电纺丝牺牲模板法与原位合成法制备自支撑COFs纤维膜(COFs fiber membrane,COFs-M)。分析COFs-M的微观形貌、比表面积、孔径分布、晶体结构和热稳定性能,并探究铀溶液pH值、吸附时长、铀起始质量浓度以及循环吸附-解吸次数等因素对COFs-M铀吸附性能的影响。结果表明:COFs-M纤维截面呈多级孔结构,拥有远高于粉末的比表面积(77.48 m^(2)/g),微孔以小于2 nm为主,有利于促进铀酰离子的传质过程;具有良好结晶性和热稳定性;在pH值为6.00时吸附量最高,最大理论吸附容量达217.97 mg/g,较传统粉末状COFs(67.53 mg/g)提升了2.2倍,吸附过程符合伪二级动力学模型,实现快速化学吸附;经6次循环使用后,铀酰吸附率仍保持在91.18%以上,有效克服了粉末回收困难与吸附团聚问题。该文制备的COFs-M保留了原有粉末的优异化学结构,而且通过提供铀酰离子快速迁移的传质通道和暴露更多的吸附位点等方式提高了吸附能力,为海水提铀材料的实际应用提供了创新策略。 展开更多
关键词 共价有机框架 静电纺丝 海水提铀 吸附 多级孔结构
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