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LLM-KE: An Ontology-Aware LLM Methodology for Military Domain Knowledge Extraction 认领 引用 被引量：2
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作者 Yu Tao Ruopeng Yang +3 位作者 Yongqi Wen Yihao Zhong Kaige Jiao Xiaolei Gu 《Computers, Materials & Continua》 SCIE EI 2026年第1期2045-2061,共17页
Since Google introduced the concept of Knowledge Graphs(KGs)in 2012,their construction technologies have evolved into a comprehensive methodological framework encompassing knowledge acquisition,extraction,representati... Since Google introduced the concept of Knowledge Graphs(KGs)in 2012,their construction technologies have evolved into a comprehensive methodological framework encompassing knowledge acquisition,extraction,representation,modeling,fusion,computation,and storage.Within this framework,knowledge extraction,as the core component,directly determines KG quality.In military domains,traditional manual curation models face efficiency constraints due to data fragmentation,complex knowledge architectures,and confidentiality protocols.Meanwhile,crowdsourced ontology construction approaches from general domains prove non-transferable,while human-crafted ontologies struggle with generalization deficiencies.To address these challenges,this study proposes an OntologyAware LLM Methodology for Military Domain Knowledge Extraction(LLM-KE).This approach leverages the deep semantic comprehension capabilities of Large Language Models(LLMs)to simulate human experts’cognitive processes in crowdsourced ontology construction,enabling automated extraction of military textual knowledge.It concurrently enhances knowledge processing efficiency and improves KG completeness.Empirical analysis demonstrates that this method effectively resolves scalability and dynamic adaptation challenges in military KG construction,establishing a novel technological pathway for advancing military intelligence development. 展开更多
关键词 Knowledge extraction natural language processing knowledge graph large language model
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Predicting rare earth extraction efficiency with organophosphorus ligands:A data-driven machine learning approach 认领 引用 被引量：1
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作者 Qihan Zhang Haitao Wang +2 位作者 Ziyi Liu Zhaomin Hao Wuping Liao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2026年第7期2204-2214,I0007,共11页
Organophosphorus ligands are widely employed as extractants in industrial rare-earth(RE)separation;however,their design and optimization have largely been guided by empirical methodologies rather th an systematic,rati... Organophosphorus ligands are widely employed as extractants in industrial rare-earth(RE)separation;however,their design and optimization have largely been guided by empirical methodologies rather th an systematic,rational approaches.In this work,we present a data-driven machine learning framework for predicting the distribution ratios(D)of RE elements in extraction processes using various organophosphorus ligands.To support this effort,a curated database comprising over 3500 experimental D measurements was established,encompassing 43 distinct ligands and 16 RE elements(excluding radioactive promethium)under varied extraction conditions.By integrating ligand descriptors,metal ion properties,and extraction parameters,we developed a convolutional neural network(CNN)model that achieves robust performance,with R2values of approximately 0.98 for training and 0.83 for testing.Our analysis further identified key factors-such as aqueous pH,ligand structural fragments,partial charges,metal ionic radii and topological features-that govern extraction behavior and correlate with specific mechanisms.Finally,the predictive capability of model was validated by accurately forecasting the D value of a newly synthesized ligand HA. 展开更多
关键词 Rare earths Extraction Machine learning Organophosphorus ligands Distribution ratios
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Optimizing pe+pH via integrated water management and phosphorus fertilization enhances phytoextraction of Cd/As by rice plant in contaminated paddy soils 认领 引用
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作者 Rui Huang Yunhe Xie +6 位作者 Xin Wang Wei Wei Bingyu Li Jingmin Yang Haoyu Chen Saihua Liu Xionghui Ji 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第8期821-831,共11页
Elevated accumulation of cadmium(Cd)and arsenic(As)in rice threatens human health.However,this offers a potential phytoremediation strategy for contaminated paddy soils.This study investigated how integrated water reg... Elevated accumulation of cadmium(Cd)and arsenic(As)in rice threatens human health.However,this offers a potential phytoremediation strategy for contaminated paddy soils.This study investigated how integrated water regimes(continuous flooding,intermittent irrigation with prolonged drying,moistening irrigation)and phosphate fertilizers(calcium magnesium phosphate and ammonium dihydrogen phosphate)optimize soil pe+pH to enhance rice-mediated extraction of labile Cd/As.The intermittent irrigation with ammonium dihydrogen phosphate(IADP)treatment yielded the highest pe+pH(mean 8.30)during growth cycles,mobilizing labile Cd and increasing soil Cd extraction by rice,leading to 0.32 mg/kg(19%)reduction in potentially plant-available soil Cd.Conversely,the continuous flooding with calcium magnesium phosphate(FCMP)treatment achieved the lowest pe+pH(mean 3.50),significantly elevating labile As and promoting As uptake by rice,ultimately decreasing potentially plant-available As by 4.3 mg/kg(13%)compared to the original soil.Notably,the moistening irrigation with ammonium dihydrogen phosphate(MADP)treatment resulted in concurrent reductions in both potentially plant-available soil Cd(14%)and As(6%).At maturation,diffusion gradients in thin films(DGT)-labile Cd and As concentrations in surface soil(0-5 cm)under IADP and FCMP decreased by 68%and 10%,respectively,compared to subsurface layers(6-14 cm),demonstrating preferential Cd/As depletion from surface horizons.This study shows that the proposed optimized soil pe+pH through water management combined with phosphorus fertilizer regimes can enhance the depletion of bioavailable Cd/As by rice,providing a technically feasible and cost-effective strategy for remediating contaminated paddy soils. 展开更多
关键词 Rice plant extraction Arsenic Cadmium Water management Phosphate fertilizer
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Efficient separation of rhenium and molybdenum in phosphoric-sulfuric mixed-acid medium via tertiary amine extraction 认领 引用
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作者 LIU Rui-zhuo FAN Ruo-bin +2 位作者 ZHAO Zhong-wei LIU Dong-fu LI Yong-li 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第6期2459-2476,共18页
The selective recovery of rhenium(Re)from molybdenum(Mo)-rich hydrometallurgical solutions is a persistent challenge,hindered by the chemical similarity of the two elements and the poor performance of conventional ext... The selective recovery of rhenium(Re)from molybdenum(Mo)-rich hydrometallurgical solutions is a persistent challenge,hindered by the chemical similarity of the two elements and the poor performance of conventional extraction systems.This study elucidates a highly efficient separation strategy using the tertiary amine extractant N235,uniquely enabled by a synergistic phosphoric-sulfuric mixed-acid medium.We reveal a novel dual-pathway separation mechanism termed"acidity regulation and ion competition".Specifically,sulfuric acid modulates the solution acidity to promote the dissociation of extractable molybdate anions(PMo12O403-)into non-extractable MoO22+.Concurrently,phosphoric acid introduces a high concentration of competitive phosphate anions that saturate the extractant's active sites,effectively suppressing the co-extraction of any residual anionic Mo species.This synergistic effect,corroborated by FT-IR and DFT calculations,leads to exceptional selectivity.Under optimized conditions,a single-stage Re extraction of 98.6%was achieved with only 1.4%Mo co-extraction,yielding an outstanding separation factor(βRe/Mo)of 4183.Furthermore,the loaded Re was efficiently stripped(>98.2%)using 1 mol/L aqueous ammonia,and the organic system demonstrated excellent stability,maintaining over 96.3%extraction efficiency after six cycles.This work presents not only a robust and industrially viable process but also a new mechanistic paradigm for separating chemically analogous metals by synergistically manipulating solution speciation and competitive equilibria. 展开更多
关键词 rhenium molybdenum separation solvent extraction tertiary amine mixed-acid medium
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Research progress of iron extraction from red mud and resource utilization of remaining tailings 认领 引用
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作者 Chao-Gang Zhou Xin-Ze Zhang +7 位作者 Yu Long Da-Chao Qi Dao-Zheng Liu Zhan-Hui Yan Qing Zhao Xu Gao Shu-Huan Wang Wei Gong 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2026年第6期397-416,共20页
Red mud is an alkaline solid waste generated by the alumina industry.Its annual global emissions have exceeded 180 million tons,and its prolonged open storage is prone to causing soil alkalization and air pollution.Re... Red mud is an alkaline solid waste generated by the alumina industry.Its annual global emissions have exceeded 180 million tons,and its prolonged open storage is prone to causing soil alkalization and air pollution.Red mud is considered to be a potential secondary resource given its rich valuable metal content.To realize the efficient resource utilization of red mud and convert solid waste into useful resources as much as possible,related researchers have carried out various studies on the recovery of iron from red mud.The relevant literature in recent years was summarized and analyzed.The research progress of iron resource recovery technology from red mud and the resource utilization of its tailings were also reviewed.In terms of iron recovery technologies,the process principles,technical characteristics,and limitations of these technologies for traditional methods such as physical sorting,pyrometallurgy,and hydrometallurgy,as well as emerging technologies including bioleaching,biomass pyrolysis reduction,and electrochemistry,are highlighted.A comparative analysis of the applicability of various technologies provides theoretical support for the selection of iron recovery processes under different conditions.At the same time,for the characteristics of the tailings produced after iron extraction from red mud,the ways of resource utilization in the fields of building materials and cementitious materials are discussed in depth,so as to realize the efficient utilization of the components of red mud.Finally,based on the research results obtained above and the current problems of red mud resource utilization,the sustainable development direction of red mud resource utilization in the future is prospected. 展开更多
关键词 Red mud Iron recovery Iron extraction tailing Resource utilization
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Anti-Polyelectrolyte-Effect Hydrogel Unlocks Efficient Uranium Extraction from Concentrated Seawater 认领 引用
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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
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T-Pointer:A Chinese Text Semantic Extraction Model for Semantic Communication 认领 引用
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作者 Qian Liping Qian Jiang +3 位作者 Wu Wanwan Huang Liang Wu Yuan Yang Xiaoniu 《China Communications》 SCIE EI CSCD 2026年第2期298-311,共14页
Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future... Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future sixth-generation(6G)wireless networks.In this paper,we propose a Chinese text semantic extraction model,namely T-Pointer,to improve the quality of semantic extraction by integrating the Transformer with the pointer-generator network.The proposed T-Pointer model consists of a semantic encoder and a semantic decoder.In the encoding stage,we use the multi-head attention mechanism of the Transformer to extract semantic features from the input Chinese text.In the decoding stage,we first use the Transformer to extract multi-level global text features.Then,we introduce the pointer-generator network model to directly copy the keyword information from the source text.The simulation results demonstrate that the T-Pointer model can improve the bilingual evaluation understudy(BLEU)and recalloriented understudy for gisting evaluation(ROUGE)by 14.69%and 14.87%on average in comparison with the state-of-the-art models,respectively.Also,we implement the T-Pointer model on a semantic communication system based on the universal software radio peripheral(USRP)platform.The result shows that the packet delay of semantic transmission can be reduced by 52.05%on average,compared to traditional information transmission. 展开更多
关键词 attention mechanism pointer-generator network semantic communication semantic extraction transformer
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Phosphorus fractions of ornithogenic soil profiles in coral islands using P k-edge XANES,sequential extraction,and31P-NMR spectroscopy 认领 引用
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作者 Xianglong Xi Yongli Zhou +5 位作者 Xueying Wang Zhangqin Zheng Yulu Xue Libin Wu Liqiang Xu Xiaodong Liu 《Acta Geochimica》 EI CAS CSCD 2026年第4期1041-1054,共14页
The Xisha Islands accumulated significant amounts of phosphorus(P)due to seabird guano input.However,the seabird population has declined significantly in recent years as a result of climate change and human activities... The Xisha Islands accumulated significant amounts of phosphorus(P)due to seabird guano input.However,the seabird population has declined significantly in recent years as a result of climate change and human activities.As plant communities develop,significant amounts of organic matter and nitrogen were introduced into the soil through plant humus.To investigate the effects of different sources on the distribution of phosphorus fractions during the past~1000 years of ecological evolution,we conducted k-edge x-ray absorption near-edge structural spectroscopy(XANES),sequential extraction,and31P nuclear magnetic resonance(31P-NMR)of soil phosphorus in two ornithogenic soil profiles from the Xisha Islands.Combining these methods,the results revealed that magnesium-bound phosphorus(Mg-P)in modern guano underwent mineralization after deposition,and its content decreased by>50%.Subsequently,it may be released and combine with the abundant calcium-bearing minerals to transform into calcium-bound phosphorus(Ca-P).The results of XANES and sequential extraction indicated that Ca-P dominated the soil phosphorus pool by up to 70%–90%.The distributions of total organic carbon,total nitrogen,and total phosphorus in the soil profile are consistent with the evolutionary characteristics of nutrient supply from guano or plant humus during historical periods.In addition,although plant humus has lower total phosphorus content than guano,it may be an important source of organic phosphorus for topsoil.This study provides insights into the evolution of coral island ecosystems by examining phosphorus fractions and sources of phosphorus and offers valuable references for understanding nutrient cycling on tropical coral islands. 展开更多
关键词 Coral island Soil phosphorus fractions XANES Sequential extraction 31P-NMR
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Recycling of spent LiFePO4 extraction slag:Current status and future prospects 认领 引用
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作者 Yufa Feng Huijie Wang +8 位作者 Wei Yang Huiqin Hu Hengyu Zhu Wei Ren Guang Yang Lei Zhou Liming Yang Honggen Peng Xubiao Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2026年第3期721-736,共16页
Recovering LiFePO4 extraction slag(LES)-the FePO4-rich residue formed after Li leaching from spent LiFePO4-has become pivotal to minimizing resource losses,mitigating environmental risks,and advancing circula... Recovering LiFePO4 extraction slag(LES)-the FePO4-rich residue formed after Li leaching from spent LiFePO4-has become pivotal to minimizing resource losses,mitigating environmental risks,and advancing circularity in lithium-ion battery value chains.However,integrative frameworks that link closed-loop routes(returning to battery precursors/cathodes)with non-closed-loop upcycling are still limited,constraining process optimization and scale-up.This review synthesizes current progress in LES recycling with emphasis on maximizing recovery efficiency and product value.In closed-loop pathways,hydrometallurgical purification removes impurities to yield battery-grade FePO4 as an LiFePO4 precursor,while direct relithiation(e.g.,solid-state sintering aided by Li sources and reductants)restores Li and reduces Fe3+to Fe2+,thereby regenerating LiFePO4 cathodes from LES.In non-closed-loop pathways,compositionally guided upcycling converts LES into advanced materials(e.g.,high-performance electrodes,highcapacity adsorbents),thereby broadening the techno-economic value propositions.We also distill lessons from early industrial practice,identifying constraints arising from feedstock variability,energy-cost coupling(thermal/chemical utilities),and product-quality assurance(battery-grade specifications).Finally,we map research directions-including data-driven feed characterization and process control,defecthealing relithiation strategies and interfacial engineering,quality grading and market pathways,and multi-scenario deployment-to enhance the technical and economic sustainability of LES recycling and accelerate its contribution to a circular battery economy. 展开更多
关键词 LiFePO4extraction slag Closed-loop regeneration Non-closed-loop regeneration Application
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Sustainable construction of multistage porous LiMn2O4 thick electrode by 3D printing for enhanced electrochemical lithium extraction from brine 认领 引用
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作者 Li Zhang Guiling Luo +7 位作者 Yanhong Chao Muyao He Jun Gu Jianquan Deng Jiangtao Yu Minmeng Tang Xiaowei Li Wenshuai Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2026年第3期546-557,共12页
Electrochemical liquid lithium extraction technology has attracted much attention because of its high selectivity,good efficiency,and eco-friendliness.However,the low energy density per unit area and poor stability of... Electrochemical liquid lithium extraction technology has attracted much attention because of its high selectivity,good efficiency,and eco-friendliness.However,the low energy density per unit area and poor stability of traditional thin film electrodes(F-LMO),as well as manganese dissolution loss induced by the Jahn-Teller distortion of LiMn2O4,hinder their industrial scalability.Herein,a durable and high-efficiency multistage porous LiMn2O4 thick electrode was prepared sustainably by 3D printing technology(3DPLMO)for enhancing lithium recovery from salt lake brine.The multistage porous structure reduced the mass transfer resistance and shortened the ion diffusion path,which was conducive to accelerating the diffusion rate of Li+.Simultaneously,the three-dimensional conductive networks composed of reduced graphene oxide(r GO)and carbon nanotubes(CNT)synergized with the multistage pores effectively weakened the polarization phenomenon of the electrode and improved the stability of 3DP-LMO.The3DP-LMO exhibited a 5.5-fold higher extraction capacity per unit area and the Mn dissolution loss rate was only 1/15 compared with the F-LMO.Notably,the capacity retention rate of 3DP-LMO was 87.6%,significantly better than that of F-LMO(66.3%).Based on the quasi-in situ X-ray Diffraction results,the mechanism of lithium intercalation and deintercalation in 3DP-LMO was elucidated.Furthermore,lithium extraction parameters were optimized using response surface method-center composite design(RSM-CCD),resulting in an increase in lithium extraction capacity to 15.66 mg g-1and a reduction in energy consumption to only 12.33 Wh mol-1.The results show that 3DP-LMO has significantly improved lithium extraction performance and stability,and has considerable prospects in practical application. 展开更多
关键词 Lithium extraction Electrochemistry 3D printing Multistage pores Three-dimensional conductive network
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Surface Sulfate Modification Promoted Excitons Extraction of BiOBr Nanosheets for Efficient1O2Photosynthesis and Chlorophenols Dechlorination 认领 引用
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作者 Yan-Biao Shi Zhi-Ping Yang +6 位作者 Chen-Chen Zhang Pin-Ji Chen Hao-Yang Fu Xu-Peng Liu Hao Li Bo Lai Li-Zhi Zhang 《Rare Metals》 SCIE EI CAS CSCD 2026年第2期283-294,共12页
Photocatalytic molecular oxygen(O2)activation provides a sustainable approach to produce singlet oxygen(1O2)for organic contaminants detoxification.However,the charge carriers-involved pathway usually suffers... Photocatalytic molecular oxygen(O2)activation provides a sustainable approach to produce singlet oxygen(1O2)for organic contaminants detoxification.However,the charge carriers-involved pathway usually suffers from unsatisfactory1O2production efficiency owing to energy loss caused by photogenerated hole-mediated superoxide species(·O2-)oxidation.If the photoinduced species could be directly extracted onto photocatalysts surface rather than completely separated into electron and holes,traditional built-in electric field-triggering charge-carriers extraction process might be circumvented,promoting the electroneutral excitons-mediated1O2production.Herein,we demonstrate that introducing sulfate ions on bismuth oxybromide surface([SO4]-BiOBr)using a facile photoetching-coordination strategy can regulate its steric hindrance and surface excitonic states.Benefiting from the energy gradient from the bulk to surface excitonic states,[SO4]-BiOBr exhibits extremely high-efficiency bulk exciton extraction performance.Different from the counterparts favoring the O2chemisorption via a side-on mode,[SO4]-BiOBr with larger steric hindrance preferentially transfers the energy of long-lived excitons to physically absorbed O2,resulting in the photocatalytically generated reactive oxygen species(ROS)switching from·O2-to1O2and thereby boosting the dechlorination and degradation of 4-chlorophenol(4-CP).This study reveals the pivotal effect of surface modification on regulating the excitonic processes of semiconductors for efficient1O2photosynthesis and subsequent wastewater purification. 展开更多
关键词 BiOBr chlorophenol degradation exciton extraction O2activation singlet oxygen
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Intelligent feature extraction for anaerobic/anoxic/aerobic process in municipal wastewater treatment plant 认领 引用
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作者 Honggui Han Yaqian Zhao +1 位作者 Xiaolong Wu Hongyan Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第3期360-371,共12页
In the municipal wastewater treatment plants(MWWTPs),significant fluctuations in flow rate result in time delays and non-uniform distribution,making it challenging to accurately capture the real dynamics.Feature extra... In the municipal wastewater treatment plants(MWWTPs),significant fluctuations in flow rate result in time delays and non-uniform distribution,making it challenging to accurately capture the real dynamics.Feature extraction can extract useful information from complex process data for wastewater treatment process monitoring.However,non-uniform distribution poses a challenge for effective feature extraction.To tackle this issue,a sparse autoencoder feature extraction method(SAFEM)is designed to improve monitoring accuracy.Firstly,the influence of the thrust rate on sample distribution is analyzed in conjunction with MWWTPs inflow fluctuations,and residence time between the two monitoring points is analyzed by hydrodynamic mechanism.Secondly,by constructing a sparse matrix,the distribution of non-zero element is used to reflect the inhomogeneity of the sample distribution,which can effectively capture the high-dimensional sparsity.Thirdly,based on the sparse autoencoder,the loss function is designed for feature extraction,which could better adapt to the change of sample distribution and improve the accuracy of feature extraction in the wastewater treatment process.Finally,the effectiveness of SAFEM is illustrated with experimental studies from a real MWWTP in China.The abnormal condition diagnosis performance of SAFEM shows that SAFEM can extract MWWTPs features accurately. 展开更多
关键词 Municipal wastewater treatment plants Feature extraction Deep learning Non-uniform distribution
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A novel application of a stepwise extraction protocol:resolving the challenge of biomarker detection in high-maturity shale systems 认领 引用
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作者 Jing-Ya Zhang Bo-Wen Meng +2 位作者 Ru-Kai Zhu Hua-Sen Zeng Chang Liu 《Petroleum Science》 SCIE EI CAS CSCD 2026年第3期1280-1292,共13页
Biomarkers in source rocks are crucial in uncovering biological source and depositional environment.However,the detection of critical biomarkers such as steranes and terpanes in high-maturity source rocks is often cha... Biomarkers in source rocks are crucial in uncovering biological source and depositional environment.However,the detection of critical biomarkers such as steranes and terpanes in high-maturity source rocks is often challenging.On one hand,biomarkers in high-maturity source rocks are inherently present at low concentrations;on the other hand,the detection of these low-concentration biomarkers can be hampered by the high concentrations of interfering compounds,such as n-alkanes and other branched/cyclic alkanes.In this study,we developed a sample pretreatment protocol of stepwise extraction,using the combination of solvent in varying polarities(i.e.,n-hexane and dichloromethane)and samples of different sizes(i.e.,blocks>3 cm,2.5–5 mesh,10–20 mesh).The specific procedures are as follows:(1)removing the high amounts of interfering compounds during the first-step extraction to increase the relative proportion of biomarkers in saturated fraction by extracting coarse samples with relatively weak-polar solvents;(2)analyzing the soluble organic matter extracted in the second step by Gas chromatography-mass spectrometry(GC-MS)for biomarker(i.e.,steranes and terpanes)detection by extracting samples of 100–200 mesh with solvents of stronger polarity.This method was demonstrated using organic-rich shales with high maturity(Ro=1.42%)from the Qingshankou Formation(Fm.)in the Gulong Sag,and it was validated using the medium maturity(Ro=1.0%)shales from the Qingshankou Fm.,Sanzhao Sag,Songliao Basin.The results show that under routine Soxhlet extraction combining GC-MS analysis,sterane and terpane biomarkers in the Qingshankou shales are unidentifiable,regardless of whether urea adduction is applied or not.In contrast,these biomarkers can be successfully identified utilizing stepwise extraction coupled with GC-MS analysis.The effectiveness of biomarker identification is influenced by the interplay of both the shale particle size and organic solvent polarity.The integration of biomarker indexes was then employed to interpret the biological source and the depositional environment of the organic matter,providing detailed insights of the hydrocarbon generation potential of shales.This information can further provide additional guidance for selecting favorable resource zones for shale oil exploration in the Gulong Sag,Songliao Basin. 展开更多
关键词 Source rocks Biomarker identification High maturity Stepwise extraction Gas chromatography-mass spectrometry (GC-MS)
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Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction 认领 引用
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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》 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
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Impact of organic acids on extraction of rare earth elements:Mechanisms and optimization 认领 引用
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作者 Peidong Liu Xu Wang Wencai Zhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2026年第1期299-310,共12页
Organic acids are increasingly recognized as an environmentally friendly and efficient selective leaching agent of critical minerals.However,their impact on subsequent extraction processes remains unclear.This study i... Organic acids are increasingly recognized as an environmentally friendly and efficient selective leaching agent of critical minerals.However,their impact on subsequent extraction processes remains unclear.This study investigated the extraction behavior of rare earth elements(REEs),representative of critical minerals,in the presence of various organic acids,including citric acid,maleic acid,malonic acid,DLmalic acid,L(+)-tartaric acid,and L-ascorbic acid.Organic acids exhibit a slight inhibitory effect on REE extraction,while significantly enhancing the extraction of Al(Ⅲ),thereby complicating REE separation.Therefore,the concentration of organic acids should be maintained as low as possible in practical applications.Under the optimized conditions,the inhibitory effects on REEs are negligible,and undesired Al extraction is minimized by adjusting contact time.The study identifies malonic and L(+)-tartaric acids as particularly effective for selective separation.Mechanistically,organic acids are likely to form complexes with REEs and D2EHPA during extraction,except for Y(Ⅲ),offering practical guidelines for optimizing REE recovery.The recovery of organic acids can be achieved by precipitating REEs from stripping solutions using oxalic acid,adding further environmental and economic benefits.This study provides both theoretical insights and experimental evidence for the separation of REEs from aqueous containing organic acids,offering a valuable reference for the recovery of other critical minerals from such solutions. 展开更多
关键词 Organic acid Solvent extraction Rare earths D2EHPA
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Push-pull extraction strategy using DTPA as a complexing agent for enhanced separation of lutetium and ytterbium 认领 引用
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作者 Zilong Yang Jingquan Cai +2 位作者 Chuanying Liu Shuainan Ni Chengliang Xiao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2026年第6期1907-1914,I0008,共8页
The efficient separation of lutetium(Lu)and ytterbium(Yb)re mains a significant challenge in rare earth elements processing due to their nearly identical chemical properties.In this work,a"push-pull"synergis... The efficient separation of lutetium(Lu)and ytterbium(Yb)re mains a significant challenge in rare earth elements processing due to their nearly identical chemical properties.In this work,a"push-pull"synergistic extraction system was developed,utilizing a mixture of phosphate ester extractants(named HP350)as the extractant and diethylenetriamine-N,N,N',N",N"-pentaacetic acid(DTPA)as the watersoluble complexing agent,aiming to achieve a higher selective separation of Lu3+and Yb3+.The effects of HP350 and DTPA concentrations,the equilibrium pH of the aqueous phase,and the extraction equilibration time on the separation performance of Lu3+/Yb3+ were systematically investigated.Notably,under the optimal conditions,the separation factor of Lu/Yb(SFLu/Yb)in the HP350-DTPA"push-pull"extraction system reaches 2.58±0.08,compared to only 1.81 with HP350 extractant alone.This result also greatly exceeds most of the extractants reported so far.Besides,the thermodynamic modeling results provide additional evidence that the presence of DTPA in the aqueous phase enhances the SFLu/Yb.The stripping experiment demonstrates that the SFLu/Yb of DTPA as a scrubbing agent is comparable to that of the extraction stage.Batch counter-current extraction experiments further confirm the efficacy of the"push-pull"extraction strategy,with the purity of Lu increasing from 48.0 wt%to 97.4 wt%after 10 extraction stages and 10 scrubbing stages.This study offers a novel approach to the efficient separation of Lu and Yb and demonstrates the potential of the"push-pull"extraction system in rare earth separation processes. 展开更多
关键词 Rare earths Lu/Yb separation Solvent extraction "Push-pull"effect
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Efficient gold extraction process from refractory gold concentrate based on Bi-alloy formation 认领 引用
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作者 Bai-qi SUN Wei-feng LIU +3 位作者 Du-chao ZHANG Lin CHEN Xu-heng LIU Tian-zu YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2026年第7期2172-2184,共13页
To improve the efficiency of gold extraction and address environmental pollution issues associated with conventional cyanide processes,a novel process was proposed to concentrate gold stepwise by iron matte and Bi-all... To improve the efficiency of gold extraction and address environmental pollution issues associated with conventional cyanide processes,a novel process was proposed to concentrate gold stepwise by iron matte and Bi-alloy.Firstly,theoretical analysis was conducted to confirm the feasibility of the new process.Three Bi-containing agents were selected to enhance gold capture in iron matte smelting.Subsequently,the effects of agents and Bi content on gold recovery rate in iron matte smelting were investigated.The gold content of slag decreases to 0.10 g,with a gold recovery rate of 99.53%.The distribution of Bi in iron matte is beneficial to the gold recovery.Furthermore,molten reverse extraction was conducted,thus resulting in a gold-enriched alloy with a gold content of 182.47 g.Finally,the entire process experiment was conducted to recycle iron matte and increase gold content in gold-enriched alloy.The gold content of gold-enriched alloy reached more than 400 g. 展开更多
关键词 refractory gold concentrate iron matte smelting molten reverse extraction Au−Bi alloy
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Long-term outcomes following lens extraction surgery in acute primary angle closure 认领 引用
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作者 Yi-Ning Guo Jing Ding +3 位作者 Hao-Ran Ai Xin-Zuo Zhou Xue-Min Li Chun Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2026年第2期281-290,共10页
AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longit... AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longitudinal observational study,detailed medical histories of APAC patients and comprehensive ophthalmic examinations at final followup were collected.Logistic regression analysis was performed to identify predictors of blindness.Univariate and multivariate linear regression analyses were conducted to determine risk factors associated with visual outcomes.RESULTS:This study included 39 affected eyes of 31 subjects(26 females)with an average age of 74.1±8.0y.At 6.7±4.2y after APAC attack,2(5.7%)eyes had bestcorrected visual acuity(VA)worse than 3/60.Advanced glaucomatous visual field loss was observed in 15(39.5%)affected eyes and 5(25.0%)fellow eyes.Nine affected eyes(23.7%)had GON,and 11(28.9%)were blind.Six(15.4%)affected eyes and 2(9.1%)fellow eyes had suspicious progression.A significantly higher blindness rate in factory workers compared to office workers.Logistic regression identified that worse VA at attack(OR 10.568,95%CI 1.288-86.695;P=0.028)and worse early postoperative VA(OR 13.214,95%CI 1.157-150.881;P=0.038)were risk factors for blindness.Multivariate regression showed that longer duration of elevated intraocular pressure(P=0.004)and worse early postoperative VA(P=0.009)were associated with worse visual outcomes.CONCLUSION:Despite LE surgery,some APAC patients experience continued visual function deterioration.Lifelong monitoring is necessary.Target pressure and progression rates should be re-evaluated during follow-up. 展开更多
关键词 acute primary angle closure lens extraction surgery long-term follow-up visual impairment glaucomatous optic neuropathy
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A pipeline approach for entity and relationship extraction in geological hazard texts using BERT-BiLSTM-CRF with self-attention 认领 引用
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作者 Yange Li Yudan Shao +1 位作者 Li Luo Zheng Han 《Intelligent Geoengineering》 2026年第2期169-178,共10页
Geohazard knowledge is a vital component of geological knowledge bases,playing a crucial role in disaster prevention and risk assessment.However,existing information extraction methods struggle with long-distance depe... Geohazard knowledge is a vital component of geological knowledge bases,playing a crucial role in disaster prevention and risk assessment.However,existing information extraction methods struggle with long-distance dependencies in geohazard texts,leading to poor performance in extracting relevant entities and their semantic relationships.To address this,we propose a pipeline approach based on deep learning models for enhanced geohazard information extraction.First,the BERT-BiLSTM-CRF model is applied to extract five types of entities in the geohazard domain,achieving an average F1-score of 90.22%.This demonstrates the model’s ability to effectively capture the semantic meaning of entities in geohazard texts.Next,to tackle the issue of long-distance semantic dependencies,a self-attention mechanism is introduced in the relation extraction task,combined with the BERT-BiLSTM-CRF model.The F1-score for relation extraction reaches an average of 82.7%,significantly improving the model's stability in recognizing relationships in long texts.Experimental results show that the proposed method outperforms traditional approaches in both entity and relation extraction,thus improving the accuracy of geohazard knowledge extraction.These findings promote the intelligent application of geohazard information and further enrich and refine geological knowledge bases. 展开更多
关键词 Geological hazards Entity extraction Relationship extraction Self-attention mechanism BERT
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Microfluidic extraction of phenolic compounds from wastewater in the straight/helical/in-plane spiral microchannels 认领 引用
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作者 Yabing Qi Chumeng Zhao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2026年第3期188-205,共18页
The extraction of phenol was conducted in the straight,helical and in-plane spiral microchannels using tributyl phosphate,methyltri-n-octylammonium chloride and 1-butyl-3-methylimidazolium hexafluorophosphate in keros... The extraction of phenol was conducted in the straight,helical and in-plane spiral microchannels using tributyl phosphate,methyltri-n-octylammonium chloride and 1-butyl-3-methylimidazolium hexafluorophosphate in kerosene,respectively.The results indicated that initial phenol concentration had little effect on phenol extraction efficiency but led to a near-linear increase in space-time yield of phenol.The phenol extraction efficiency initially rose sharply with capillary length before stabilizing,whereas space-time yield of phenol decreased continuously with increasing capillary length.Both extraction efficiency and space-time yield of phenol declined with increasing capillary inner diameter.In the straight microchannel,the phenol extraction efficiency increased with overall volumetric flow rate before leveling off,while in the in-plane spiral microchannel,it decreased with increasing flow rate.The space-time yields in both straight and in-plane spiral microchannels increased rapidly with rising overall volumetric flow rate.The extraction efficiency and space-time yield of phenol decreased with increasing helical diameter and pitch.Horizontal placement of the helical microchannel yielded higher extraction efficiency and space-time yield of phenol compared to vertical placement.Increasing the volume fraction of extractant in the extractant phase improved both extraction efficiency and spacetime yield of phenol.Under optimal conditions,phenol extraction efficiencies in all three microchannels exceeded 99.8%.Among phenol-containing wastewater with identical flow rates and concentrations,the in-plane spiral microchannel demonstrated superior phenol extraction performance compared to the other two microchannel types.The improvement of extraction efficiency and spacetime yield of phenol were realized through both reduction in microchannel dimensions and increase in the curvature of the microchannel. 展开更多
关键词 Phenolic compounds Wastewater Microchannels Extraction Ionic liquids Response surface methodology
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