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Artificial intelligence-enabled high-precision colony extraction and isolation system
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作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
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Coordination-driven in-situ reduction and extraction of neptunium
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作者 Huaixin Hao Shuyun Zhang +7 位作者 Xue Dong Qilong Tang Yuxiao Guo Yaoyang Liu Jing Chen Jing Su Zhipeng Wang Chao Xu 《Science China Chemistry》 2026年第2期777-783,共7页
The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation st... The recycling of neptunium(Np)from nuclear wastes is crucial for the sustainable development of nuclear energy,yet it is still a challenging task owing to the complexity of Np chemistry.Precise control of oxidation state is highly desirable for the effective recovery of Np.In this study,we report an innovative strategy for Np recovery through in-situ coordination and reduction of Np(Ⅴ)in a biphasic extraction system.By leveraging the synergistic effects of coordination by a P=O donating ligand(trialkyl phosphine oxide,TRPO)and reduction by hydroquinone(HQ)in the organic phase,efficient Np(Ⅴ)-to-Np(Ⅳ)conversion and high distribution ratio(D)of Np were achieved in a single extraction contact.The reduction mechanism of Np was elucidated through spectroscopic and theoretical analyses.This work enriches the redox chemistry of Np and provides a novel pathway for Np recovery in advanced nuclear fuel cycles. 展开更多
关键词 NEPTUNIUM COORDINATION REDUCTION extraction
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Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
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作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS Uranium extraction
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Straightforward and versatile construction of phenanthroline-derived diamide ligands for f-block element extraction
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作者 Dong Fang Xiaofan Yang +1 位作者 Fengxin Gao Chengliang Xiao 《Chinese Chemical Letters》 2026年第1期602-605,共4页
As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive stu... As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive study.In this work,we first report a convenient synthetic method for the construction of DAPhen using Friedländer reaction by two facile steps(vs.previous 12 steps).A variety of DAPhen ligands are readily available,especially unsymmetrical ones,which give us a platform to systematically study the substituent effect on f-block elements extraction performance.The performance of unsymmetrical extractants is experimentally confirmed to falls between that of their corresponding symmetrical extractants by extracting UO_(2)^(2+) as the representative f-block element.This work provides a direct and versatile method to synthesize symmetrical and unsymmetrical DAPhen,which paves way for the investigations on their coordination properties with metal ions and other applications. 展开更多
关键词 Phenanthroline diamide ligand Friedlander reaction UNSYMMETRICAL SYMMETRICAL Solvent extraction
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Cutting-edge aminated conjugated microporous poly(aniline)s enabled high-performance membrane for seawater uranium extraction
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作者 Xiaoxia Ye Bingqing Huang +7 位作者 Xueying Chen Yaping Wang Zhihong Zheng Yifan Liu Yuancai Lv Chunxiang Lin Jian Huang Jie Chen 《Green Energy & Environment》 2026年第1期181-194,共14页
The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by th... The extraction of uranium from seawater via membrane adsorption is a promising strategy for ensuring a long-term supply of uranium and the sustainability of nuclear energy.However,this approach has been hindered by the longstanding challenge of identifying sustainable membrane materials.In response,we propose a prototypal hybridization strategy to design a novel series of aminated conjugated microporous polymer(CMPN)@collagen fiber membrane(COLM).These sustainable and low-cost membrane materials allow a rapid and high-affinity kinetic to capture 90%of the uranium in just 30 min from 50 ppm with a high selectivity of Kd>105 mL·g^(−1).They also afford a robustly reusable adsorption capacity as high as 345 mg·g^(−1)that could harvest 1.61 mg·g^(−1)of uranium in a short 7-day real marine engineering in Fujian Province,even though suffered from very low uranium concentration of 3.29μg·L^(−1)and tough influence of salts such as 10.77 g·L^(−1)of Na^(+),1.75μg·L^(−1)of VO_(3)^(−)etc.in the rough seas.The structural evidence from both experimental and theoretical studies confirmed the formation of favorable chelating motifs from the amino group on CMPN-COLM,and the intensification by the synergistic effect from the size-sieving action of CMPN and the capillary inflow effect of COLM. 展开更多
关键词 Conjugated microporous polymer Collagen fiber MEMBRANE Seawater Uranium extraction
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Enhanced Multi-Scale Feature Extraction Lightweight Network for Remote Sensing Object Detection
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作者 Xiang Luo Yuxuan Peng +2 位作者 Renghong Xie Peng Li Yuwen Qian 《Computers, Materials & Continua》 2026年第3期2097-2118,共22页
Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targ... Deep learning has made significant progress in the field of oriented object detection for remote sensing images.However,existing methods still face challenges when dealing with difficult tasks such as multi-scale targets,complex backgrounds,and small objects in remote sensing.Maintaining model lightweight to address resource constraints in remote sensing scenarios while improving task completion for remote sensing tasks remains a research hotspot.Therefore,we propose an enhanced multi-scale feature extraction lightweight network EM-YOLO based on the YOLOv8s architecture,specifically optimized for the characteristics of large target scale variations,diverse orientations,and numerous small objects in remote sensing images.Our innovations lie in two main aspects:First,a dynamic snake convolution(DSC)is introduced into the backbone network to enhance the model’s feature extraction capability for oriented targets.Second,an innovative focusing-diffusion module is designed in the feature fusion neck to effectively integrate multi-scale feature information.Finally,we introduce Layer-Adaptive Sparsity for magnitude-based Pruning(LASP)method to perform lightweight network pruning to better complete tasks in resource-constrained scenarios.Experimental results on the lightweight platform Orin demonstrate that the proposed method significantly outperforms the original YOLOv8s model in oriented remote sensing object detection tasks,and achieves comparable or superior performance to state-of-the-art methods on three authoritative remote sensing datasets(DOTA v1.0,DOTA v1.5,and HRSC2016). 展开更多
关键词 Deep learning object detection feature extraction feature fusion remote sensing
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LLM-KE: An Ontology-Aware LLM Methodology for Military Domain Knowledge Extraction
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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》 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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Accurate closed-form flutter eigensolutions of three-dimensional composite laminates with shear deformation
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作者 Dezhuang PAN Yufeng XING 《Chinese Journal of Aeronautics》 2026年第1期230-246,共17页
According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing ... According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing differential equations are derived by the Hamilton's variational principle,and then solved by the iterative Separation-of-Variable(i SOV)method,which are applicable to arbitrary combinations of homogeneous Boundary Conditions(BCs).However,only the simply-support,clamped and cantilever panels are considered in this work for the sake of clarity.With the closed-form eigensolutions,the flutter frequency,flutter mode and flutter boundary are presented,and the effect of shear deformation and aerodynamic damping on flutter frequencies is investigated.Besides,the relation between panel energy and the work of aerodynamic load is discussed.The numerical comparisons reveal the following.(A)The flutter eigenvalues obtained by the present method are accurate,validated by the Finite Element Method(FEM)and the Galerkin method.(B)When the span-chord ratio is larger than 3,simplifying a 3D panel to 2D(two-dimensional)panel is reasonable and the relative differences of the flutter points predicted by the two models are less than one percent.(C)The reciprocal relationship between the mechanical energy of the panel and the work done by aerodynamic load is verified by using the present flutter eigenvalues and modes,further indicating the high accuracy of the present solutions.(D)The coupling of shear deformation and aerodynamic damping prevents frequency coalescing. 展开更多
关键词 Closed-form eigensolutions The first-order piston theory The Mindlin plate theory three-dimensional panel flutter Separation-of-variable method
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Recycling of High-Purity Lithium Metal from Waste Battery by Photoelectrochemical Extraction at Ultralow Overall Potential
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作者 Longfei Yang Chao Huang +3 位作者 Yanhong Lyu Dawei Chen Aibin Huang Jianyun Zheng 《Nano-Micro Letters》 2026年第4期371-388,共18页
To ease the scarcity of lithium(Li)resource and cut down on environmental pollution,an efficient,selective,inexpensive and sustainable Li recycling process from waste batteries is needed,which is yet to be achieved.He... To ease the scarcity of lithium(Li)resource and cut down on environmental pollution,an efficient,selective,inexpensive and sustainable Li recycling process from waste batteries is needed,which is yet to be achieved.Here,we report a low-potential photoelectrochemical(PEC)system that selectively and efficiently extracts Li metals from multi-cation electrolytes under 1 sun illumination.Based on the difference of redox potential,we can get rid of the disturbance of other cations(i.e.,Fe,Co and Ni ions)by a bias-free PEC device to realize the extraction of high-purity Li metals on a coplanar Si-based photocathode-TiO_(2) photoanode tandem device at 2 V of applied bias(far less than the redox potentials of Li^(+)/Li).In such system,the extraction rate of Li metals(purity>99.5%)exceeds 1.35 g h^(-1)m^(-2)with 90%of Faradaic efficiency.Long-term experiments,different electrode/electrolyte tests,and various price assessments further demonstrate the stability,compatibility and economy of PEC extraction system,enabling a solar-driven pathway for the recycling of critical metal resources. 展开更多
关键词 Photoelectrochemical method Lithium metals Waste batteries Ultralow-potential device Selective and efficient extraction
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Synergistic lock-anchor engineered diketopyrrolopyrrole-COFs for efficient photocatalytic uranium extraction
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作者 Fengtao Yu Xiaolong Zhang +5 位作者 Jie Xu Guihong Wu Huiying Lei Zhiwu Yu Jianding Qiu Jianli Hua 《Journal of Energy Chemistry》 2026年第1期284-293,I0007,共11页
As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term... As a key low-carbon energy source,nuclear power plays a vital role in the global transition toward sustainable energy.Photocatalytic uranium extraction from seawater(UES)offers a promising solution to ensure long-term uranium supply but is challenged by ultra-low uranium concentrations and ion interference.To overcome these issues,we design three diketopyrrolopyrrole-based covalent organic frameworks(COFs)via a synergisticπ-extended lock and carboxyl-functionalized anchor molecular engineering strategy.Among them,TPy-DPP-COF features a covalently lockedπ-conjugated structure that enhances planarity,optimizes energy alignment,and minimizes exciton binding energy,thereby promoting charge transfer and suppressing recombination.Concurrently,carboxyl groups enable uranyl-specific coordination and create local electric fields to facilitate charge separation.These features contribute to the outstanding performance of TPy-DPP-COF,which achieves a high uranium adsorption capacity of 16.33 mg g−1 in natural seawater under irradiation,with only 29.3%capacity loss after 10 cycles,surpassing industrial benchmarks.Density functional theory(DFT)calculations and experimental studies reveal a synergistic photocatalysis-adsorption pathway,with DPP units acting as active sites for uranium reduction.This work highlights a molecular design strategy for developing efficient COF-based photocatalysts for practical marine uranium recovery. 展开更多
关键词 DIKETOPYRROLOPYRROLE Covalent organic frameworks Exciton binding energy Photocatalytic uranium extraction Synergistic effect
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Long-term outcomes following lens extraction surgery in acute primary angle closure
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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)》 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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From bench to buoy:challenges in seawater uranium extraction
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作者 Zhenli Sun Hanyang Wang +5 位作者 Zhongshan Chen Xishi Tai Jiehong Lei Baowei Hu Suhua Wang Xiangke Wang 《Science China Materials》 2026年第3期1416-1419,共4页
Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear ... Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear power plants in a few years.Uranium-235 serves as the primary fissile material for the fabrication of nuclear fuel.However,there are only about 6.14 million tons of uranium resources on land,which can sustain~70 years of operation for global nuclear power plants.Thereby,the recovery of uranium from spent fuel,radioactive waste solutions,seawater,and salt lakes is crucial for the healthy development of nuclear power utilization[2-4]. 展开更多
关键词 carbon neutrality china nuclear power plantstherebythe peaking carbon dioxide emissions sustainable economic development fissile material nuclear energy seawater uranium extraction nuclear power plants
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A state-of-the-art review of automated extraction of rock mass discontinuity characteristics using three-dimensional surface models 被引量:11
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作者 Rushikesh Battulwar Masoud Zare-Naghadehi +1 位作者 Ebrahim Emami Javad Sattarvand 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第4期920-936,共17页
In the last two decades,significant research has been conducted in the field of automated extraction of rock mass discontinuity characteristics from three-dimensional(3D)models.This provides several methodologies for ... In the last two decades,significant research has been conducted in the field of automated extraction of rock mass discontinuity characteristics from three-dimensional(3D)models.This provides several methodologies for acquiring discontinuity measurements from 3D models,such as point clouds generated using laser scanning or photogrammetry.However,even with numerous automated and semiautomated methods presented in the literature,there is not one single method that can automatically characterize discontinuities accurately in a minimum of time.In this paper,we critically review all the existing methods proposed in the literature for the extraction of discontinuity characteristics such as joint sets and orientations,persistence,joint spacing,roughness and block size using point clouds,digital elevation maps,or meshes.As a result of this review,we identify the strengths and drawbacks of each method used for extracting those characteristics.We found that the approaches based on voxels and region growing are superior in extracting joint planes from 3D point clouds.Normal tensor voting with trace growth algorithm is a robust method for measuring joint trace length from 3D meshes.Spacing is estimated by calculating the perpendicular distance between joint planes.Several independent roughness indices are presented to quantify roughness from 3D surface models,but there is a need to incorporate these indices into automated methodologies.There is a lack of efficient algorithms for direct computation of block size from 3D rock mass surface models. 展开更多
关键词 Rock mass Discontinuity characterization Automatic extraction three-dimensional(3D)point cloud
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Evaluating Soil Dissolved Organic Matter Extraction Using Three-Dimensional Excitation-Emission Matrix Fluorescence Spectroscopy 被引量:8
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作者 XIE Wenming ZHANG Shanshan +4 位作者 RUAN Lin YANG Mingyue SHI Weiming ZHANG Hailin LI Weihua 《Pedosphere》 SCIE CAS CSCD 2017年第5期968-973,共6页
Soil dissolved organic matter (DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of di... Soil dissolved organic matter (DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of different DOM components are poorly understood. We extracted DOM from three soils using different extraction times, solid to liquid ratios (SLR), and extraction solution (KC1) concentrations, and evaluated the extractions using three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy. The sum of the contents of the main DOM components (protein-, fulvic-, and humic-like compounds) increased by 0.6-3.5, 2.5-3.9, and 0.11 0.37 times (P 〈 0.05) when SLR decreased from 1:2 to 1:10, the extraction solution concentration increased from 0.01 to 1.5 mol L-1, and extraction time increased from 10 to 300 rain, respectively. The three-dimensional EEM fluorescence spectroscopy is a useful tool to characterize the components of DOM and evaluate DOM extraction in soils. 展开更多
关键词 dissolved organic matter components extraction conditions extraction time KC1 concentration solid to liquid ratio
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A New Three-Dimensional Code for Simulation of Ion Beam Extraction: Ion Optics Simulator
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作者 金大志 黄桃 +1 位作者 胡权 杨中海 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第4期516-518,共3页
A new thee-dimensional code, ion optics simulator (IOS), to simulate ion beam extraction is developed in visual C++ language. The theoretical model, the flowchart of code, and the results of calculation as an exam... A new thee-dimensional code, ion optics simulator (IOS), to simulate ion beam extraction is developed in visual C++ language. The theoretical model, the flowchart of code, and the results of calculation as an example are presented. 展开更多
关键词 ion beam extraction ion optics SIMULATION
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Solvent extraction with a three-dimensional reticulated hollow-strut SiC foam microchannel reactor
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作者 Ye Zhang Yong Gao +3 位作者 Peng Wang Duo Na Zhenming Yang Jinsong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第6期53-62,共10页
Recently,there has been considerable interest in the use of microchannel reactors for hydrometallurgy of rare earths(REs).Here,a novel integrated microchannel reactor based on the hollow-strut SiC foam material is pre... Recently,there has been considerable interest in the use of microchannel reactors for hydrometallurgy of rare earths(REs).Here,a novel integrated microchannel reactor based on the hollow-strut SiC foam material is presented and demonstrated to extract Ce^(3+)and Pr^(3+)using 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester(P507)as the extractant.The typical three-dimensional reticulated structure of the hollow-strut SiC foam was characterized by scanning electron microscopy and X-ray micro computed tomography.Since the reactor’s structure plays a key role in fluid mixing and mass diffusion during the extraction process,the structure-performance relationship of the foam was studied by extraction experiments combined with numerical simulations.Using the foam with the optimal structure,the influence of the flow rate Q_(0) of the two liquid phases on the extraction efficiency η and overall volume mass transfer coefficient KLa was discussed.For both RE ions,with increasing Q_(0),η decreases while KLa increases.For the total flow rate of the two phases of 4 ml·min^(-1),the η values of Pr^(3+)and Ce^(3+)reached 98.7%and 97.0%,respectively.For the total flow rate of 36 ml·min^(-1) which was much higher than that of many other microchannel reactors reported in the literatures,the η values of Pr^(3+)and Ce^(3+)still reached 92.2%and 86.9%,respectively,and the KLa values of Pr^(3+)and Ce^(3+)were 0.198 and 0.161 s^(-1),respectively,similar to the high values reported for other microchannel reactors studied in previous work.These findings indicate that the hollow-strut SiC foam microchannel reactor is suitable for use in REs extraction. 展开更多
关键词 extraction HOLLOW Foam Microchannels Numerical simulation
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A three-dimensional feature extraction-based method for coal cleat characterization using X-ray μCT and its application to a Bowen Basin coal specimen
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作者 Yulai Zhang Matthew Tsang +4 位作者 Mark Knackstedt Michael Turner Shane Latham Euan Macaulay Rhys Pitchers 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期153-166,共14页
Cleats are the dominant micro-fracture network controlling the macro-mechanical behavior of coal.Improved understanding of the spatial characteristics of cleat networks is therefore important to the coal mining indust... Cleats are the dominant micro-fracture network controlling the macro-mechanical behavior of coal.Improved understanding of the spatial characteristics of cleat networks is therefore important to the coal mining industry.Discrete fracture networks(DFNs)are increasingly used in engineering analyses to spatially model fractures at various scales.The reliability of coal DFNs largely depends on the confidence in the input cleat statistics.Estimates of these parameters can be made from image-based three-dimensional(3D)characterization of coal cleats using X-ray micro-computed tomography(m CT).One key step in this process,after cleat extraction,is the separation of individual cleats,without which the cleats are a connected network and statistics for different cleat sets cannot be measured.In this paper,a feature extraction-based image processing method is introduced to identify and separate distinct cleat groups from 3D X-ray m CT images.Kernels(filters)representing explicit cleat features of coal are built and cleat separation is successfully achieved by convolutional operations on 3D coal images.The new method is applied to a coal specimen with 80 mm in diameter and 100 mm in length acquired from an Anglo American Steelmaking Coal mine in the Bowen Basin,Queensland,Australia.It is demonstrated that the new method produces reliable cleat separation capable of defining individual cleats and preserving 3D topology after separation.Bedding-parallel fractures are also identified and separated,which has his-torically been challenging to delineate and rarely reported.A variety of cleat/fracture statistics is measured which not only can quantitatively characterize the cleat/fracture system but also can be used for DFN modeling.Finally,variability and heterogeneity with respect to the core axis are investigated.Significant heterogeneity is observed and suggests that the representative elementary volume(REV)of the cleat groups for engineering purposes may be a complex problem requiring careful consideration. 展开更多
关键词 Cleat separation Cleat statistics Feature extraction Discrete fracture network(DFN)modeling
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Analytical and Numerical Model Confrontation for Transfer Impedance Extraction in Three-Dimensional Radio Frequency Circuits
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作者 Olivier Valorge Fengyuan Sun +3 位作者 Jean-Etienne Lorival Mohamed Abouelatta-Ebrahim Francis Calmon Christian Gontrand 《Circuits and Systems》 2012年第2期126-135,共10页
3D chip stacking is considered known to overcome conventional 2D-IC issues, using through silicon vias to ensure vertical signal transmission. From any point source, embedded or not, we calculate the impedance spread ... 3D chip stacking is considered known to overcome conventional 2D-IC issues, using through silicon vias to ensure vertical signal transmission. From any point source, embedded or not, we calculate the impedance spread out;our ultimate goal will to study substrate noise via impedance field method. For this, our approach is twofold: a compact Green function or a Transmission Line Model over a multi-layered substrate is derived by solving Poisson’s equation analytically. The Discrete Cosine Transform (DCT) and its variations are used for rapid evaluation. Using this technique, the substrate coupling and loss in IC’s can be analyzed. We implement our algorithm in MATLAB;it permits to extract impedances between any pair of embedded contacts. Comparisons are performed using finite element methods. 展开更多
关键词 Through Silicon Via (TSV) Green’s Function Transmission Line Model Radio Frequency (RF) Transfer IMPEDANCE extraction
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Construction of a Maritime Knowledge Graph Using GraphRAG for Entity and Relationship Extraction from Maritime Documents 被引量:3
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作者 Yi Han Tao Yang +2 位作者 Meng Yuan Pinghua Hu Chen Li 《Journal of Computer and Communications》 2025年第2期68-93,共26页
In the international shipping industry, digital intelligence transformation has become essential, with both governments and enterprises actively working to integrate diverse datasets. The domain of maritime and shippi... In the international shipping industry, digital intelligence transformation has become essential, with both governments and enterprises actively working to integrate diverse datasets. The domain of maritime and shipping is characterized by a vast array of document types, filled with complex, large-scale, and often chaotic knowledge and relationships. Effectively managing these documents is crucial for developing a Large Language Model (LLM) in the maritime domain, enabling practitioners to access and leverage valuable information. A Knowledge Graph (KG) offers a state-of-the-art solution for enhancing knowledge retrieval, providing more accurate responses and enabling context-aware reasoning. This paper presents a framework for utilizing maritime and shipping documents to construct a knowledge graph using GraphRAG, a hybrid tool combining graph-based retrieval and generation capabilities. The extraction of entities and relationships from these documents and the KG construction process are detailed. Furthermore, the KG is integrated with an LLM to develop a Q&A system, demonstrating that the system significantly improves answer accuracy compared to traditional LLMs. Additionally, the KG construction process is up to 50% faster than conventional LLM-based approaches, underscoring the efficiency of our method. This study provides a promising approach to digital intelligence in shipping, advancing knowledge accessibility and decision-making. 展开更多
关键词 Maritime Knowledge Graph GraphRAG Entity and Relationship extraction Document Management
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Review on micro-mechanism of forming emulsification during rare earth extraction by acidic extractants 被引量:2
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作者 Jie Liu Yuxiu Zhao +6 位作者 Zhirong Wang Minghui Jia Wenxiang Xia Guizhi Wu Wenda Guo Ru'an Chi Kun Huang 《Journal of Rare Earths》 2025年第1期9-20,I0001,共13页
Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or... Solvent extraction is the main method used to separate and purify rare earth elements.In the process of rare earths extraction,emulsification often generated due to the instability of the aqueous and organic phases or improper operating conditions.Once emulsification occurs,it would not only lead to low rare earths recovery efficiency,small product quantities,high production costs and the losing of extractant and rare earth resources,but also result in serious environmental pollution.Therefore,it is very important to study the micro-mechanisms of emulsification and establish new methods to prevent emulsification at the source.In this paper,possible factors resulting in emulsification,such as the compositions and properties of the organic and aqueous phases,the operating conditions of the rare earths extraction are reviewed.The micro-mechanisms of emulsification are summarized basing on the microscopic structures in the bulk phase,aggregations of the extractants at the organic-aqueous interface,spectral characterizations and computational simulations.On this basis,new formation mechanisms are proposed for emulsification.Preliminary explorations are employed to verify the correctness of these new viewpoints.Finally,future directions for studies of the emulsification micro-mechanism are proposed.This study provides a theoretical basis for further understanding the micro-mechanisms of interfacial instability resulting in emulsification in the process of rare earths extraction. 展开更多
关键词 extraction Rare earths EMULSIFICATION Mechanism Interface
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