期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到8,574篇文章
< 1 2 … 250 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Micro-Textural Fingerprints of Uranium Minerals within Carbonaceous Debris: A Case Study from the Ordos Basin 认领 引用
1
作者 Fan Zhang Yangquan Jiao +1 位作者 Liqun Wu Hui Rong 《Journal of Earth Science》 SCIE CAS CSCD 2026年第1期81-91,共11页
Carbonaceous debris(CD) is widely disseminated within sandstones in the Shuanglong uranium deposit,southern Ordos Basin,and is the dominant enrichment agent for uranium precipitation.The occurrence and chemical compos... Carbonaceous debris(CD) is widely disseminated within sandstones in the Shuanglong uranium deposit,southern Ordos Basin,and is the dominant enrichment agent for uranium precipitation.The occurrence and chemical composition of uranium minerals within CD were investigated by using scanning electron microscope and electron microprobe analyses.The results show that uranium minerals mostly occur in cell pores in the forms of fructus aurantia and concentric band structure.Pitchblende and coffinite are the main uranium minerals,and the former is dominant.According to the crystal morphology and composition of trace elements of uranium minerals,uranium precipitation on the pores is grouped into two periods,orderly Ⅰ,Ⅱ.Moreover,the Ⅰ period is further divided into two sub-period,orderly Ⅰ1,Ⅰ2.Moreover,askew sphere uranium minerals could indicate fluid migration.Under certain geological environment condition,uranium is unevenly adsorbed on the surface of the pore by the Van der Waals(i.e.,Ⅰ1 period),and then is precipitated towards to the center of the pore until the whole pore is filled up with uranium minerals by complicated process such as microorganism activities(i.e.,Ⅰ2,Ⅱ period).It will provide some guidance for studying the metallogenic environment and genesis of sandstone-type uranium deposit. 展开更多
关键词 uranium occurrences cell pores carbonaceous debris sandstone-type uranium deposit Shuanglong uranium deposit
暂未订购 下载PDF
On the role of global atmospheric oxygenation processes in uranium metallogeny of Proterozoic unconformity-related uranium deposits 认领 引用 被引量：1
2
作者 PEK A A PETROV V A +3 位作者 Ziying LI Linfei QIU Jian GUO Mingming TIAN 《世界核地质科学》 CAS 2026年第1期1-21,共21页
The article is devoted to the problems of the influence of global processes of Great Oxygenation Event of the Earth’s atmosphere on the genesis of Proterozoic unconformity-type uranium deposits in the Canadian sedime... The article is devoted to the problems of the influence of global processes of Great Oxygenation Event of the Earth’s atmosphere on the genesis of Proterozoic unconformity-type uranium deposits in the Canadian sedimentary Athabasca basin,which are the most prominent representatives of large-scale uranium deposits with uniquely rich ores with uranium content up to a few tens of percentages in the world.The influence of the formation of an oxygen atmosphere on the process of ore formation is considered with a comparative analysis of single-stage and multi-stage models of the formation of unconformity uranium deposits.The appearance of free oxygen in the Earth’s atmosphere,necessary for the formation of the unconformity deposits,occurred approximately 2.5-2.0 billion years ago during the Great Oxygenation Event(GOE).The Great Oxidation Event caused the atmosphere to form high levels of oxygen,leading to the production of more primary biological matter on the early Earth,thereby forming more organic-rich sediments,which played an important role in U-mineralization of Proterozoic unconformity-related uranium deposits.The formation of the Athabasca basin began approximately 1740 Ma ago.Uranium mineralization in the deposits occurred 1590 Ma ago.This was followed by a series of putative post-ore events with rejuvenated ages from 1525 to 1000-950 Ma,which in the single-stage deposit formation model were interpreted as re precipitation of primary ore mineralization with the formation of the deposits’ore resource from both of its main sources:the mobilization of uranium from uranium-bearing minerals of the Athabasca Group sandstones and from the basement rocks of the basin.We adopted an alternative genetic model the way from their source to the basin reservoirs,which formed the resource of primary uranium of the initial stage,and 2)initially barren(after the depletion of the ore reserve of the Athabasca sandstones on basin fluids that leached uranium from uranium-bearing especially organic of multi-stage deposit formation with two spatially and temporally separated uranium sources:1)ore-forming basin brines of the Athabasca sandstones with an initially elevated uranium content during its mobilization from uranium-bearing rocks along the brine migration route on rocks of the basin basement with the formation of an‘additional’uranium resource at subsequent stages with a rejuvenated ages.The deposition of primary uranium of the initial stage and‘additional’uranium occurred in structural traps localizing the initial stage uranium,with a concomitant increase in the total reserves and ore grades of the deposits.After the depletion of the‘additional’uranium in the basement available for mobilization,the formation of the ore resource of the deposits was completed.We adopted this conclusion as a hypothesis for a possible interpretation of the mechanism for the final completion of the geological history of the Athabasca basin deposits in the Mesoproterozoic Era,1600-1000 Ma ago. 展开更多
关键词 Athabasca basin uranium deposits inheritance of migration routes ‘additional’uranium structural traps localization of early-stage uranium
暂未订购 下载PDF
Genesis Mechanism of Heat Source in Mianhuakeng Uranium Deposit,South China:Insights from Radiogenic Heat Production of Granite Bodies 认领 引用
3
作者 WANG Siqi ZHANG Baojian +2 位作者 LÜGuosen LIU Feng ZHU Xi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 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
暂未订购 下载PDF
The combined exposure exacerbates the toxic effect of cadmium and uranium on rice seedlings 认领 引用
4
作者 Jun Liu Meihan Cai +8 位作者 Jiajie Zhang Aili Mo Shiyu Hu Peishuang He Menglei Jiang Wei Zhao Cuiying Peng Tangjian Peng Fei Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第4期444-455,共12页
Studies on the phytotoxicity of cadmium(Cd)and uranium(U)in rice mainly focus on single exposure.However,water,soil,and other environmental media are always co-contaminated by Cd and U.The effects of Cd(5 mg/L)and U(1... Studies on the phytotoxicity of cadmium(Cd)and uranium(U)in rice mainly focus on single exposure.However,water,soil,and other environmental media are always co-contaminated by Cd and U.The effects of Cd(5 mg/L)and U(10 mg/L)single and combined exposure for 7 days on rice seedlings were explored by hydroponic experiment.The synergism of U and Cd intensified the inhibitory effect of combined exposure on the rice seedling’s growth,accompanied by a remarkable reduction in chlorophyll content,alterations in antioxidant capacity,imbalances in mineral element metabolism,lipid peroxidation-induced destruction observed in rice seedlings,and significantly regulated expression of OsNramp5,OsHMA3,and OsHMA2,the adverse effects on the roots were more severe compared to those on the shoots.Combined exposure of U and Cd altered the distribution of U and Cd in the rice plant and subcellular.The accumulation of U and Cd in the rice seedlings’roots observably exceeded the shoot.Cd is mainly isolated in the vacuole and cell wall;U is primarily trapped in the cell wall.Cd promoted U accumulation in rice seedlings,while U inhibited Cd accumulation in rice seedlings.These findings can not only expand the understanding of the phytotoxicity of heavy metal combined exposure but also have important theoretical and practical significance for evaluating and remedying heavy metals contaminated-paddy soil and ensure for safe production of rice. 展开更多
关键词 Cadmium Uranium Combined exposure Phytotoxicity Rice seedling
暂未订购 下载PDF
Synergistic enhancement of uranium(VI)immobilization by humin–iron hydroxide composites:Performance and mechanisms 认领 引用
5
作者 Yang-yang Zhang Ni-jiao Chen +1 位作者 Huan Deng Bo Zu 《Water Science and Engineering》 EI CAS CSCD 2026年第2期257-268,共12页
Composite systems of soil organic matter and iron hydroxides hold significant potential for the remediation of heavy metal pollution.However,the synergistic immobilization mechanisms of U(Ⅵ)by humin(HM)—iron hydroxi... Composite systems of soil organic matter and iron hydroxides hold significant potential for the remediation of heavy metal pollution.However,the synergistic immobilization mechanisms of U(Ⅵ)by humin(HM)—iron hydroxide composites remain insufficiently understood.In this study,goethite(Ge)—HM and magnetite(Mag)—HM composites with varying C-to-Fe molar ratios were synthesized via co-precipitation,and their adsorption behavior and underlying mechanisms towards U(Ⅵ)in aqueous solutions were systematically investigated.The results showed that under conditions of a pH value of 5.0 and temperature of 298 K,the maximum U(Ⅵ)adsorption capacities of Ge—HM and Mag—HM reached 60.56 mg/g and 64.12 mg/g,respectively,significantly surpassing those of pure Ge(39.6 mg/g),Mag(22.5 mg/g),and HM(20.2 mg/g).Kinetic studies revealed that the adsorption processes for both Ge—HM and Mag—HM conformed to the pseudo-second-order kinetic model,indicating chemical reaction control.Isothermal adsorption results were well described by the Langmuir model,suggesting monolayer adsorption on the composite surfaces.Crucially,characterization results elucidated distinct reaction mechanisms.Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)analyses revealed that U(Ⅵ)primarily complexed with oxygencontaining functional groups,such as carboxyl and hydroxyl groups,on both composite surfaces,leading to stable immobilization.For Mag—HM,a notable reduction of U(Ⅵ)to U(Ⅳ)was observed,with XPS U 4f spectra showing characteristic U(Ⅳ)peaks,indicating a significant reductive immobilization pathway facilitated by the presence of both Mag and HM.In contrast,for the Ge—HM composite with a Cto-Fe ratio of 0.5,the complete consumption of Fe(Ⅱ)after U(Ⅵ)adsorption,with its proportion in total Fe decreasing from 53.7%to zero,strongly suggested that Fe(Ⅱ)played a key role in electron transfer during the immobilization process.This study elucidates the synergistic enhancement mechanisms of HM—iron hydroxide composites in U(Ⅵ)removal,providing new insights for developing green and efficient materials for the remediation of heavy metal pollution. 展开更多
关键词 Uranium Humin Goethite Magnetite Co-precipitation
暂未订购 下载PDF
Anti-Polyelectrolyte-Effect Hydrogel Unlocks Efficient Uranium Extraction from Concentrated Seawater 认领 引用
6
作者 Hui Wang Feng Gao +5 位作者 Taohong Xu Peng Liu Zhanhu Guo Guanbing Zhou Yihui Yuan Ning Wang 《Engineering》 SCIE EI CSCD 2026年第5期198-209,共12页
Uranium extraction from seawater is a promising strategy to alleviate global uranium scarcity,yet its implementation is hindered by extremely low concentrations and complex ionic environments.Concentrated seawater bri... Uranium extraction from seawater is a promising strategy to alleviate global uranium scarcity,yet its implementation is hindered by extremely low concentrations and complex ionic environments.Concentrated seawater brine,a byproduct of salt production and desalination,contains 2-10 times more uranium than natural seawater,yet its high salinity presents additional challenges for extraction.Conventional polyamidoxime(PAO)hydrogels exhibit salt-induced shrinkage,compromising functional group accessibility and adsorption efficiency.Herein,we develop an anti-polyelectrolyte effect hydrogel by composing polyvinylphosphonic acid(PVPA)and the PAO.Under high-salinity conditions,cations and anions accumulate via diffusion around the positively charged amidoxime and negatively charged phosphonic acid groups,weakening interchain electrostatic attractions.This anti-polyelectrolyte effect promotes hydrogel swelling,significantly improving the exposure of binding sites and uranyl ion uptake.The PVPA-PAO hydrogel achieves a uranium adsorption capacity of 43.89 mg·g-1 after 24 days in concentrated natural seawater derived from solar saltworks,significantly surpassing that of previously reported PAO hydrogels(~10 mg·g-1).In addition,it exhibits excellent antibacterial performance,mechanical robustness,and ion selectivity.This work presents an effective strategy for improving uranium recovery from marine resources and advances the comprehensive development and utilization of seawater resources. 展开更多
关键词 Uranium extraction Concentrated seawater Anti-polyelectrolyte effect Functional group accessibility Anti-biofouling
暂未订购 下载PDF
Effect of Palaeoclimate and Palaeoenvironment on Tabular Uranium Mineralisation: Insight From the Upper Cretaceous Qingshankou Formation in the Qianjiadian Area of Songliao Basin, NE China 认领 引用
7
作者 Shaohua Huang Xiao Huang +5 位作者 Mingkuan Qin Zhongbo He Yingying Geng Renjie Zhang Zhangyue Liu Wenjian Jiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2026年第3期934-955,共22页
Several sandstone-type uranium deposits were identified within the Upper Cretaceous red-variegated strata in the Qianjiadian area of the Songliao Basin,NE China.However,a consensus regarding the genesis of multilayer ... Several sandstone-type uranium deposits were identified within the Upper Cretaceous red-variegated strata in the Qianjiadian area of the Songliao Basin,NE China.However,a consensus regarding the genesis of multilayer tabular ore bodies within a sandstone reservoir remains elusive.This paper investigates the provenance,palaeoenvironment,and unique mineralisation characteristics of the Qingshankou Formation within the newly discovered Dalin deposit on the basis of lithofacies,element-environmentorganic geochemistry and stable isotopes.The results indicate that the fragment provenance of the ore-bearing strata is primarily composed of intermediate-felsic rocks,and the source areas are characterised by a complex tectonic background that encompasses both passive and active continental margins,as well as continental arcs.Its sedimentary environment shows a general(semi-) arid and hot palaeoclimate,with ancient lacustrine water exhibiting both fresh and brackish properties.Pure grey mudstone(PGM)features low Fe2O3T but exhibits elevated levels of ferrous iron,uranium,molybdenum,Fe2+/Fe3+ratio and reduction capacity;pure red mudstone(PRM) displays contrasting characteristics;and certain geochemical indicators of mottled mudstone(MD) are intermediate between those of the above-mentioned mudstones.Green alteration within the MD is identified as having a synsedimentary origin,as opposed to the previously assumed secondary reduction of foreign hydrocarbons.The associated organic matter is classified as Type-Ⅲ kerogen,initially derived from aquatic plankton and herbaceous plants.Finally,a sedimentary model is proposed for the red-variegated Qingshankou Formation in the study area,where the original interbedded architecture with varying geochemical properties is influenced by alternations in palaeoclimate and associated redox stratification of ancient lacustrine water.Some lenticular native grey beds,which were deposited in local low-lying lands during semi-arid and pluvial interphases,exhibit pronounced uranium pre-concentration due to phreatic oxidation during the sedimentary stage.Subsequently,differential redox activities in the Cenozoic era led to the development of multilayer geochemical zoning and tabular ore bodies in a reservoir.This research offers valuable insights into the uranium mineralisation of oxidative red-variegated strata within global basins and contributes to the development of uranium exploration strategies. 展开更多
关键词 petrography and geochemistry Qingshankou Formation red-variegated strata sandstone-type uranium deposit Songliao Basin
暂未订购 下载PDF
Petrogenesis of Yanshanian granites in the Guidong complex,Northern Guangdong:Implications for uranium mineralization 认领 引用
8
作者 Haiyang Wang Changqian Ma +7 位作者 Jiayong Pan Fujun Zhong Fei Xia Xiangping Gu Guanghua Liu Zhengle Chen Jungang Liu Jiaming Qi 《Acta Geochimica》 EI CAS CSCD 2026年第3期554-575,共22页
The Guidong complex in northern Guangdong constitutes a key segment of the Nanling Metallogenic Belt and hosts significant granite-related uranium deposits.However,the petrogenesis of the Yanshanian intrusions in its ... The Guidong complex in northern Guangdong constitutes a key segment of the Nanling Metallogenic Belt and hosts significant granite-related uranium deposits.However,the petrogenesis of the Yanshanian intrusions in its western part remains poorly constrained because of insufficient high-precision geochronological and mineralogical data.This limitation hinders a comprehensive understanding of regional metallogenesis.To address this,we conducted an integrated study of the Siqian two-mica granite and the Changping biotite granite,incorporating zircon U-Pb geochronology,whole-rock geochemistry,Hf-Nd isotope analysis,and mineral chemistry.Our objectives were to determine their emplacement ages and to investigate their petrogenesis and relationship with uranium mineralization.Zircon U-Pb dating indicates that the Siqian and Changping granites formed at 160±1 Ma and 156±1 Ma,respectively,suggesting both were emplaced during the Early Yanshanian magmatic event.These high-K calc-alkaline rocks are peraluminous(A/CNK=1.04-1.44),enriched in large-ion lithophile elements(LILEs;e.g.,Rb,Th,U),and depleted in high-field-strength elements(HFSEs;e.g.,Ba,Nb,Ta).They exhibit negative zircon εHf(t)values ranging from-15.4 to-8.4,with corresponding crustal model ages of 1668-2142 Ma.Whole-rock samples show εNd(t)values from-11.2 to-9.1 and Nd model ages of 1693-1860 Ma.These isotopic features indicate that both plutons represent moderately differentiated S-type granites derived from partial melting of Paleo-to Mesoproterozoic metasedimentary sources(e.g.,pelitic and psammitic rocks),accompanied by fractional crystallization of minerals such as ilmenite and apatite.Integrated geochemical and mineralogical data reveal that the Siqian and Changping granites are characterized by low Th/U ratios,high F contents,and low magmatic oxygen fugacity—signatures typical of U-rich granites.These attributes provided a favorable lithogeochemical environment for uranium enrichment and acted as primary sources for uranium-bearing,high-temperature hydrothermal fluids,thereby playing a critical role in regional uranium mineralization. 展开更多
关键词 Guidong complex Granite Zircon U–Pb Petrogenesis Uranium mineralization
暂未订购 下载PDF
Biomass aerogel based on chitosan and bayberry tannin for uranium recovery from aqueous solution 认领 引用
9
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》 SCIE EI CAS CSCD 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-1and 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
暂未订购 下载PDF
Linear relationship between reactivity and the reciprocal of uranium concentration in thermal‑spectrum molten salt reactors 认领 引用
10
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》 SCIE EI CAS CSCD 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 235U’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
暂未订购 下载PDF
Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction 认领 引用
11
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》 SCIE EI CAS CSCD 2026年第1期284-293,I0007,共10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
暂未订购 下载PDF
Prompt fission neutron uranium logging(Ⅲ):logging instrument 认领 引用
12
作者 Hai‑Tao Wang Yan Zhang +9 位作者 Chi Liu Jian‑Qiang Xu Li‑Jiao Zhang Zhi‑Feng Liu Xiong‑Jie Zhang Rui Chen Qi Liu Ren‑Bo Wang Shu‑Min Zhou Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第7期115-127,共13页
The domestically developed prompt fission neutron uranium logging(PFNUL)instrument for uranium exploration represents a significant advancement in China’s deep uranium mining efforts,although it has considerable chal... The domestically developed prompt fission neutron uranium logging(PFNUL)instrument for uranium exploration represents a significant advancement in China’s deep uranium mining efforts,although it has considerable challenges and complexity.This paper presents the development of a new prompt fission neutron uranium logging instrument(named UNL4)that integrates a domestic D-T neutron generator,two 3He proportional detectors,a lanthanum bromide(LaBr3)gamma-ray detector,and a digital multi-channel pulse amplitude analyzer.The near 3He detector is shielded with 1 mm of cadmium(Cd)and 5 mm of high-density polyethylene(HDPE),enabling efficient epithermal neutron detection,whereas the far 3He detector measures thermal neutrons.A LaBr3 detector is employed for gamma-ray detection,primarily originating from uranium decay.Highspeed analog-to-digital converter(ADC)and field-programmable gate array(FPGA)technologies are used to achieve rapid acquisition and transmission of both dual-energy neutron time spectra and gamma spectra.Moreover,this paper proposes a fast signal-shaping method,which reduces the dead time effect in 3He detectors on neutron time spectra.Experiments conducted in standard model boreholes with varying uranium contents demonstrated a strong linear relationship between the epithermal-to-thermal neutron ratio(E/T)and uranium content,with a fitting coefficient of R2>0.999,confirming the accuracy of the instrument.The E/T value repeatability,in both short-term(3.16%RSD)and long-term(1.2%RSD)measurements,showed excellent stability.In addition,the instrument demonstrated good performance at neutron-logging speeds of 0.3∼3 m∕min(E/T values)and gamma logging speeds of 1∼10 m∕min.Through measurements in two ore sections of the PU model with uranium contents of 87.1 ppm and 45.6 ppm showed that RD remained below approximately 10%at logging speeds of 0–2 m/s in both cases,satisfying the requirements for engineering applications.This marks the first successful development of a neutron-logging instrument for uranium exploration based on a domestic neutron generator and signifies an important contribution to uranium resource exploration. 展开更多
关键词 Uranium exploration Neutron-logging instrument Pulsed neutron Neutron time spectrum detection
暂未订购 下载PDF
Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications 认领 引用 被引量：1
13
作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 SCIE EI CAS CSCD 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 m2g-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
暂未订购 下载PDF
Cutting-edge aminated conjugated microporous poly(aniline)s enabled high-performance membrane for seawater uranium extraction 认领 引用
14
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》 SCIE EI CAS CSCD 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−1that could harvest 1.61 mg·g−1of uranium in a short 7-day real marine engineering in Fujian Province,even though suffered from very low uranium concentration of 3.29μg·L−1and tough influence of salts such as 10.77 g·L−1of Na+,1.75μg·L−1of VO3−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
暂未订购 下载PDF
Fine electronic structure and 5f-electron localized-itinerant transition in uranium films 认领 引用
15
作者 Yun Zhang Jian Wu +10 位作者 Ying Jiang Qiuyun Chen Wei Feng Xiangfei Yang Qin Liu Xiegang Zhu Dengpeng Yuan Qiang Zhang Xinchun Lai Qunqing Hao Shiyong Tan 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第4期571-580,共10页
Uranium,the heaviest natural element,exhibits rich and complex physical behavior,including three types of charge density wave transitions and superconductivity at low temperatures.It is widely believed that these phen... Uranium,the heaviest natural element,exhibits rich and complex physical behavior,including three types of charge density wave transitions and superconductivity at low temperatures.It is widely believed that these phenomena are closely linked to the properties of 5f electrons,which are highly susceptible to external perturbations.To elucidate the detailed electronic structure,particularly the 5f electron signatures,we fabricated high-quality single-crystal uranium films on W(110)substrates using molecular beam epitaxy and investigated their fine electronic properties and temperature-dependent evolution by angle-resolved photoemission spectroscopy(ARPES).Our experiments reveal three electron pockets around the Γ point and direct hybridization between 5f electrons and conduction electrons at regions distant from Γ.The Kondo temperature extracted from ARPES and electrical resistance measurements is approximately 131 K,indicating that the 5f electrons transition from a high-temperature localized state to a low-temperature itinerant state in the thin film system.Additionally,we observe another flat band with an energy scale of 148 meV.The detailed electronic structure and direct evidence of the localized-to-itinerant transition of 5f electrons provided in this study advance the understanding of strong electronic correlations in uranium-based materials. 展开更多
关键词 uranium c-f hybridization Kondo physics
暂未订购 下载PDF
Integrated approach to uranium recovery and organic decomposition with electricity generation in a self-driven photoelectrochemical system 认领 引用
16
作者 Qingqing Yang Yi-Lin Liu +3 位作者 Haiyi Gong Qingyan Zhang Shuaishuai Guo Qingyi Zeng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第2期274-282,共9页
Simultaneous uranium recovery,organic pollutant degradation,and electricity generation were achieved by employing a self-driven photoelectrochemical(PEC)system equipped with a modified carbon felt(MCF)cathode for the ... Simultaneous uranium recovery,organic pollutant degradation,and electricity generation were achieved by employing a self-driven photoelectrochemical(PEC)system equipped with a modified carbon felt(MCF)cathode for the treatment of complex radioactive wastewater.The MCF cathode was synthesized via a facile hydrothermal method,which modified the surface functional groups on carbon felt(CF)with enhanced active site availability and facilitated interfacial charge transfer,thus improving its UO22+adsorption and reduction capacities.The self-driven PEC system with the MCF cathode demonstrated remarkable removal efficiencies and rate constants(k)for UO22+(98.8%and 0.111 min−1)and chlortetracycline hydrochloride(CTC)(92.9%and 0.028 min−1)within 40 min and 90 min,respectively,coupled with an excellent power output of 1.41 mW/cm2.Additionally,the system with the MCF cathode exhibited superior removal performance for UO22+and CTC in treating model complex wastewater under wide conditions.Even under natural sunlight,the system achieved over 80%removal efficiency for both UO22+and CTC.Moreover,the uranium immobilized on the MCF cathode was mainly reduced to U(Ⅳ)species(90.51%),and performance remained robust over ten operational cycles.The cathode surface modification strategy and its application in the system provide a cost-effective,multi-functional and high-efficiency approach to controlling nuclides and organic pollutants in complex radioactive wastewater. 展开更多
关键词 Complex radioactive wastewater Modified carbon felt Uranium recovery Organic degradation Electricity production Self-driven PEC system
暂未订购 下载PDF
Flexible two-dimensional uranium-organic framework with upgraded radiation resistant for X-ray imaging 认领 引用
17
作者 Jueqiong Wang Liwei Cheng +15 位作者 Yang Yang Dewen He Yingtong Fan Zhiwei Li Junhao Lu Yumin Wang Jia Lei Zhiyong Peng Aiping Jin Dan Zhou Zhizai Li Shuaihua Wang Lixi Chen Yaxing Wang Yanlong Wang Shuao Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第5期354-358,共5页
The intrinsic scintillation property of uranium has recently endowed this heaviest naturally occurring element with new opportunities for X-ray radiation detection and visualization.However,the low radiation stability... The intrinsic scintillation property of uranium has recently endowed this heaviest naturally occurring element with new opportunities for X-ray radiation detection and visualization.However,the low radiation stability of most uranium compounds hinders their practical application,particularly in X-ray imaging.Here,we presented a flexible two-dimensional uranium-organic framework(UOF,SCU-334)as an air-stable scintillating material for X-ray detection and,for the first time,a systematic investigation of X-ray imaging in UOFs.Following continuous high dose rate X-ray irradiation exceeding 50 Gy,which equals thousands of chest X-ray diagnoses,SCU-334 retains over 90%of its initial performance,representing a significant improvement over previously reported scintillating UOFs.The upgraded radiation resistance of SCU-334 is attributed to its flexible structure that dissipates energy more efficiently under high-energy particle bombardment through conformation fluctuation and relaxation.This work offers a promising approach to improve the radiation resistance of uranium-based scintillators. 展开更多
关键词 Uranium Metal-organic framework X-ray excited luminescence X-ray irradiation stability X-ray imaging
暂未订购 下载PDF
Production of99Mo via photofission reaction in natural-uranium-bearing molten salt targets 认领 引用
18
作者 Jun-Ze Lin Bo-Lin Fu +5 位作者 De-Yang Cui Xiao-Xiao Li Cheng-Gang Yu Jian-Hui Wu Jin-Gen Chen Xiang-Zhou Cai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第5期361-374,共14页
This study proposes a method for99Mo production via electron accelerator irradiation of a natural-uranium-bearing liquid molten salt target,with advantages including low nuclear proliferation risk,online extraction... This study proposes a method for99Mo production via electron accelerator irradiation of a natural-uranium-bearing liquid molten salt target,with advantages including low nuclear proliferation risk,online extraction capability,and low construction costs.The approach primarily produces99Mo through photofission of uranium(~95%),specifically238U(γ,f).Secondary neutrons,originating from photonuclear interactions or fission processes,contribute minimally(~5%)to99Mo production owing to their high energies and low fission cross sections.Key parameter analyses revealed that fluoride salt systems exhibit higher99Mo yield.Their performance stems from high bremsstrahlung energy loss rate and superior photon yield,making them optimal molten salt target materials.To maximize photofission and photoneutron cross sections while minimizing highenergy gamma ray shielding requirements,an electron beam energy range of 40-80 MeV is recommended.To suppress local hot spots and prevent molten salt boiling,flow conditions were introduced to enhance convective heat transfer,effectively reducing the peak temperature.At a flow velocity of 0.5 m/s and under 80 MeV energy conditions,the maximum system temperature is only 808.9 K,which is significantly lower than the boiling point of 1773 K.Under optimized parameters,the maximum annual production capacity of~(99)Mo reaches 4486.49 Ci,sufficient for millions of diagnostic procedures and equivalent to 16.37% of China's projected demand for 2030.This method provides a viable pathway for stable,large-scale99Mo production. 展开更多
关键词 99Mo Electron accelerator Molten salt Natural uranium Photofission
暂未订购 下载PDF
Pore surface engineering of hydrazone-linked covalent organic framework with tailor-made chelating sites for uranium extraction from seawater 认领 引用
19
作者 Junjie Yu Yichen Huang +8 位作者 Pengcheng Zhang Shusen Chen Yan Song Congzhi Wang Zijie Li Liyong Yuan Jipan Yu Nannan Wang Weiqun Shi 《Chinese Chemical Letters》 SCIE CAS CSCD 2026年第3期481-488,共8页
The extraction of uranium from seawater is essential for the sustainable development of the nuclear industry.Covalent organic frameworks(COFs)exhibit significant potential in uranium extraction from seawater due to th... The extraction of uranium from seawater is essential for the sustainable development of the nuclear industry.Covalent organic frameworks(COFs)exhibit significant potential in uranium extraction from seawater due to their high stability,designability,and large specific surface area.Herein,a vinyl-decorated covalent organic framework,designated as COF-IHEP5,was synthesized through acid-catalyzed solvothermal method.COF-IHEP5-COOH was constructed by post-modification strategy through the“thiol-ene”click reaction,where COF-IHEP5-COOH contains hydrazone-carbonyl and flexible carboxylic acid chelating sites on pore wall.This modification facilitates synergistic adsorption of uranium by utilizing a“nano trap”that is embedded within the COF framework.The maximum adsorption capacity of the postmodified COF-IHEP5-COOH for UO22+has reached 543.8 mg/g,representing a 1.5-fold increase compared to the unmodified COF-IHEP5.Additionally,COF-IHEP5-COOH demonstrates an extraction efficiency of approximately 80%for uranium from spiked natural seawater,featuring 4.5 times higher selectivity than vanadium.The DFT calculation results show that the adsorption of uranium orginated from the synergistic coordination of the skeleton in COF-IHEP5-COOH and carboxyl group on the side arm.This research highlights the remarkable potential of pore surface engineering in customizing active adsorption sites and offers new insights for the design of functionalized uranium adsorbents with superior binding affinity and adsorption capacities. 展开更多
关键词 Covalent organic framework Uranium extraction from seawater Adsorption and separation Thiol-ene click reaction Post-modification
暂未订购 下载PDF
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 认领 引用
20
作者 S.L.Mirmohammadi J.Safdari A.A.Ghorbanpour Khamseh 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 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
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 250 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈