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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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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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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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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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Neuroprotective effects of Boswellia extract in animal models of ischemic stroke,Parkinson's disease,and Alzheimer's disease:a systematic review and meta-analysis
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作者 Meng-Ye Zhang Yu-Cheng Liao +7 位作者 Shan Liang Ji-Ping Yu Qian Meng Yi-Wen Wang Xing-F ang Zhang Wei Quan Ya-Jun Shi Yi Ding 《Traditional Medicine Research》 2026年第2期56-68,共13页
Background:Neurological disorders(NDs),including ischemic stroke(IS),Parkinson’s disease(PD),and Alzheimer’s disease(AD),are major contributors to global morbidity and mortality.Boswellia extract has demonstrated ne... Background:Neurological disorders(NDs),including ischemic stroke(IS),Parkinson’s disease(PD),and Alzheimer’s disease(AD),are major contributors to global morbidity and mortality.Boswellia extract has demonstrated neuroprotective properties,yet a comprehensive systematic review assessing its efficacy remains absent.This study aims to evaluate the efficacy of Boswellia extract in treating NDs,with a particular focus on its effects in AD and its potential for long-term neurorestoration,thereby supporting further investigation into Boswellia’s therapeutic role in ND management.Methods:A systematic literature search was performed in PubMed,Web of Science,ScienceDirect,and Google Scholar for English-language studies published up to March 2024.Eighteen studies met the inclusion criteria and were included in the meta-analysis.The study protocol was registered on PROSPERO(CRD42024524386).Eligible studies involved rodent models of IS,PD,or AD with post-operative interventions using Boswellia extract.Data extraction focused on mechanisms of action,dosages,treatment durations,and therapeutic outcomes.Studies were excluded if they involved non-ND models,combined treatments,or had incomplete data.Two researchers independently conducted literature screening and data extraction.Statistical analyses were conducted using Stata(version 17)and RevMan(version 5.4),employing fixed or random-effects models based on heterogeneity assessments.Result s:Boswellia extract significantly improved the mean effect size for NDs(ES=1.28,95%CI(1.05,1.51),P<0.001).Specifically,it reduced cerebral infarct volume in IS(SMD=−2.87,95%CI(−3.42,−2.32))and enhanced behavioral outcomes in AD(SMD=3.26,95%CI(2.07,5.14))and PD(SMD=5.37,95%CI(3.93,6.80)).Subgroup analyses revealed that Boswellia extract exhibited superior efficacy in AD when administered orally and via intra-cerebroventricular injection.Long-term treatment with Boswellia extract suggested potential neurorestorative effects.Additionally,Boswellia extract was more effective than its monomeric constituents,highlighting its promising role in ND treatment.Conclusion:Boswellia extract demonstrates significant neuroprotective effects across various NDs,particularly in AD and in promoting long-term neurorestoration.These findings support the need for further research into Boswellia’s potential as a therapeutic agent in the management of neurological disorders. 展开更多
关键词 Boswellic acid Boswellia extract ischemic stroke Parkinson’s disease Alzheimer’s disease META-ANALYSIS
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Chinese relation extraction for constructing satellite frequency and orbit knowledge graph:A survey
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作者 Yuanzhi He Zhiqiang Li Zheng Dou 《Digital Communications and Networks》 2025年第5期1305-1317,共13页
As Satellite Frequency and Orbit(SFO)constitute scarce natural resources,constructing a Satellite Frequency and Orbit Knowledge Graph(SFO-KG)becomes crucial for optimizing their utilization.In the process of building ... As Satellite Frequency and Orbit(SFO)constitute scarce natural resources,constructing a Satellite Frequency and Orbit Knowledge Graph(SFO-KG)becomes crucial for optimizing their utilization.In the process of building the SFO-KG from Chinese unstructured data,extracting Chinese entity relations is the fundamental step.Although Relation Extraction(RE)methods in the English field have been extensively studied and developed earlier than their Chinese counterparts,their direct application to Chinese texts faces significant challenges due to linguistic distinctions such as unique grammar,pictographic characters,and prevalent polysemy.The absence of comprehensive reviews on Chinese RE research progress necessitates a systematic investigation.A thorough review of Chinese RE has been conducted from four methodological approaches:pipeline RE,joint entityrelation extraction,open domain RE,and multimodal RE techniques.In addition,we further analyze the essential research infrastructure,including specialized datasets,evaluation benchmarks,and competitions within Chinese RE research.Finally,the current research challenges and development trends in the field of Chinese RE were summarized and analyzed from the perspectives of ecological construction methods for datasets,open domain RE,N-ary RE,and RE based on large language models.This comprehensive review aims to facilitate SFO-KG construction and its practical applications in SFO resource management. 展开更多
关键词 Relation extraction Information extraction Distant supervision Parsing tree Joint entity-relation extraction
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A Review of Joint Extraction Techniques for Relational Triples Based on NYT and WebNLG Datasets
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作者 Chenglong Mi Huaibin Qin +1 位作者 Quan Qi Pengxiang Zuo 《Computers, Materials & Continua》 2025年第3期3773-3796,共24页
In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to er... In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to error propagation.To overcome the limitations of traditional pipeline models,recent research has focused on jointly modeling the two key subtasks-named entity recognition and relation extraction-within a unified framework.To support future research,this paper provides a comprehensive review of recently published studies in the field of relational triplet extraction.The review examines commonly used public datasets for relational triplet extraction techniques and systematically reviews current mainstream joint extraction methods,including joint decoding methods and parameter sharing methods,with joint decoding methods further divided into table filling,tagging,and sequence-to-sequence approaches.In addition,this paper also conducts small-scale replication experiments on models that have performed well in recent years for each method to verify the reproducibility of the code and to compare the performance of different models under uniform conditions.Each method has its own advantages in terms of model design,task handling,and application scenarios,but also faces challenges such as processing complex sentence structures,cross-sentence relation extraction,and adaptability in low-resource environments.Finally,this paper systematically summarizes each method and discusses the future development prospects of joint extraction of relational triples. 展开更多
关键词 Relation triplet extraction joint extraction methods named entity recognition relation extraction
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Development of new solid phase extraction techniques in the last ten years 被引量:5
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作者 范惠霞 邓志鹏 +1 位作者 仲浩 姚庆强 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第4期293-302,共10页
Solid phase extraction (SPE) is a widely used sample pretreatment method for separation, purification and enrichment, which has been established due to its significant advantages of time-saving, low consumption of s... Solid phase extraction (SPE) is a widely used sample pretreatment method for separation, purification and enrichment, which has been established due to its significant advantages of time-saving, low consumption of solvent, high enrichment factor, high accuracy, etc. In recent years, a variety of new SPE methods such as molecularly imprinted solid phase extraction (MISPE), magnetic solid phase extraction (MSPE), solid phase micro-extraction (SPME), etc., which are superior to the conventional SPE, have been developed and been widely applied to food, drugs, and environmental monitoring. In this paper, the basic principles and methods of SPE and its new applications in different areas are reviewed. 展开更多
关键词 Solid phase extraction Molecularly imprinted solid phase extraction Magnetic solid phase extraction Solid phase micro-extraction
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Exploration of augmented prompting methods for information extraction using large language models
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作者 Yishuo Fu Benfeng Xu +2 位作者 Mingxuan Du Quan Wang Zhendong Mao 《中国科学技术大学学报》 北大核心 2025年第7期15-24,14,I0001,共12页
Information extraction(IE)aims to automatically identify and extract information about specific interests from raw texts.Despite the abundance of solutions based on fine-tuning pretrained language models,IE in the con... Information extraction(IE)aims to automatically identify and extract information about specific interests from raw texts.Despite the abundance of solutions based on fine-tuning pretrained language models,IE in the context of fewshot and zero-shot scenarios remains highly challenging due to the scarcity of training data.Large language models(LLMs),on the other hand,can generalize well to unseen tasks with few-shot demonstrations or even zero-shot instructions and have demonstrated impressive ability for a wide range of natural language understanding or generation tasks.Nevertheless,it is unclear,whether such effectiveness can be replicated in the task of IE,where the target tasks involve specialized schema and quite abstractive entity or relation concepts.In this paper,we first examine the validity of LLMs in executing IE tasks with an established prompting strategy and further propose multiple types of augmented prompting methods,including the structured fundamental prompt(SFP),the structured interactive reasoning prompt(SIRP),and the voting-enabled structured interactive reasoning prompt(VESIRP).The experimental results demonstrate that while directly promotes inferior performance,the proposed augmented prompt methods significantly improve the extraction accuracy,achieving comparable or even better performance(e.g.,zero-shot FewNERD,FewNERD-INTRA)than state-of-theart methods that require large-scale training samples.This study represents a systematic exploration of employing instruction-following LLM for the task of IE.It not only establishes a performance benchmark for this novel paradigm but,more importantly,validates a practical technical pathway through the proposed prompt enhancement method,offering a viable solution for efficient IE in low-resource settings. 展开更多
关键词 prompt learning natural language processing few-shot information extraction zero-shot information extraction
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Green corrosion inhibition of mild steel in acidic media using Datura stramonium seed extract:A study for sustainable engineering applications
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作者 Kaoutar Hjouji Ibrahim Atemni +5 位作者 Rajesh Haldhar Moussa Ouakki Tarik Ainane Mustapha Taleb Seong-Cheol Kim Zakia Rais 《Chinese Journal of Chemical Engineering》 2025年第4期281-302,共22页
This study investigates the corrosion inhibition potential of Datura stramonium seed extracts on mild steel in 1.0 mol·L^(-1)HCl and 0.5 mol·L^(-1)H_(2)SO_(4),utilizing both ethanolic and aqueous extracts as... This study investigates the corrosion inhibition potential of Datura stramonium seed extracts on mild steel in 1.0 mol·L^(-1)HCl and 0.5 mol·L^(-1)H_(2)SO_(4),utilizing both ethanolic and aqueous extracts as ecofriendly inhibitors.Electrochemical techniques,thermodynamic studies,and quantum chemical calculations were employed to evaluate the adsorption mechanism and inhibitory action at the metal/electrolyte interface.Maximum inhibition efficie ncies of 93.1%in HCl and 97.7%in H_(2)SO_(4) were achieved with the ethanolic extract at a concentration of 0.2 g·L^(-1),while the aqueous extract demonstrated 93.8%inhibition in HCl and 96.6%in H_(2)SO_(4).Polarization curves indicated mixed-type inhibition with a slight anodic bias.The thermodynamic analysis of two extracts in both environments indicated that the K_(ads)increased and that theΔG_(ads)were close to-40 kJ·mol^(-1),suggesting that the adsorption followed the Langmuir isotherm,indicating a combination of physical and chemical adsorption.SEM/EDX analysis confirmed the formation of a protective layer,while quantum chemical studies further validated strong adsorption,evidenced by a lowΔE of 2.396 eV and an adsorption energy of-878 kcal·mol^(-1)(1kcal·mol^(-1)=4.18 kJ·mol^(-1)).These results demonstrate that Datura stramonium extracts are promising inhibitors,particularly in sulfuric acid,for industrial applications.Reason:Improved clarity,vocabulary,and technical accuracy while maintaining the original meaning. 展开更多
关键词 extractION Solvents Datura stramonium extract Corrosion Adsorption and morphology
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Selective separation of vanadium from the high-acidity leaching liquor through chelating extraction by the ketoxime extractant
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作者 Xile Tian Fancheng Meng +7 位作者 Xianglan Zhang Yongchao Wang Yahui Liu Jian Zhang Shuai Zhao Desheng Chen Lina Wang Tao Qi 《Chinese Journal of Chemical Engineering》 2025年第11期262-272,共11页
The high-acidity vanadium-containing solution contains high concentrations of iron and aluminum with pH around 0.5,the ketoxime extractant with the active ingredient of 2-hydroxy-5-nonylacetophenone oxime(HNAO,HL) was... The high-acidity vanadium-containing solution contains high concentrations of iron and aluminum with pH around 0.5,the ketoxime extractant with the active ingredient of 2-hydroxy-5-nonylacetophenone oxime(HNAO,HL) was proposed to extract vanadium from the solution.Under the phase ratio(O/A)of 1:2,HNAO concentration of 0.542 mol·L^(-1) at 25℃ for 10 min,99.06% of vanadium was extracted after a three-stage countercurrent extraction,while the extraction of impurities was less than 1%,with the separation coefficients of vanadium from iron and aluminum were 137050 and 43197,respectively.The antioxidant properties of the extractant were studied.At 25℃,the extractant basically did not undergo oxidative degradation.Besides,about 91.2% of the loaded vanadium was effectively stripped using 2.5 mol·L^(-1)Na_(2)CO_(3) solution.The extraction mechanism of vanadium was investigated through the slope analysis method,the spectral characterizations and density functional theory calculations.It has been observed that VO_(2)^(+) substitutes the H atom on the phenolic hydroxyl and coordinates with the N atom on the oxime and the O atom on the phenolic hydroxyl to form of a six-membered ring,and the extraction complexes were determined to be VO_(2)(H_(2)O)L and VO_(2)L. 展开更多
关键词 VANADIUM Solvent extraction High acidity Ketoxime extractant CHELATING
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Extraction properties of diglycolamide for rare earth:Contribution of N-substituents
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作者 Xiujing Peng Miaomiao Zhang +5 位作者 Jingjing Yin Heng Zhao Jianhui Su Yu Cui Xuchuan Jiang Guoxin Sun 《Journal of Rare Earths》 2025年第4期815-821,I0006,共8页
A successful extraction process relies heavily on an excellent extractant structure.The theory of extractant structure and extraction performance is still insufficient to guide the design of new extractants,despite ex... A successful extraction process relies heavily on an excellent extractant structure.The theory of extractant structure and extraction performance is still insufficient to guide the design of new extractants,despite extensive research into extractants.However,diglycolamide extractants have demonstrated certain advantages in nuclear fuel reprocessing and rare earth extraction and separation.This paper focuses on the synthesis of 13 structurally serially changed extractants.There is a good connection between the extraction performance and the energy consumption of the carbonyl conformation torsion of the extractant with symmetrical straight-chain alkyl substituents.The extraction capacity of extractant decreases with the increase of alkyl chain length.The methyl substituent extractant shows higher extractability than the other.The steric effect of the alkyl chain with more than two carbons is not significantly different.The relationship between the structure and performance of extractants was systematically studied by the combination of theoretical calculations and experimental data to investigate the effects of symmetric,asymmetric and branched N-substituents on extraction performance. 展开更多
关键词 N-substituents Structure and performance Diglycolamide extractants extractION Rare earths
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High extraction efficiency of N,N,N′,N′-tetracyclohexyldiglycolamide for Sr(Ⅱ):An experimental and crystal structure study
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作者 Xiujing Peng Ling Li +6 位作者 Haiyin Yu Riming Hu Jianhui Su Miaomiao Zhang Yu Cui Xuchuan Jiang Guoxin Sun 《Chinese Journal of Chemical Engineering》 2025年第1期1-9,共9页
To improve the ability of diglycolamide extractants for the extraction of Sr(Ⅱ)from high-level waste liquid,N,N,N′,N′-tetracyclohexyldiglycolamide(TCHDGA)was proposed and studied to extract Sr(Ⅱ)from nitrate media... To improve the ability of diglycolamide extractants for the extraction of Sr(Ⅱ)from high-level waste liquid,N,N,N′,N′-tetracyclohexyldiglycolamide(TCHDGA)was proposed and studied to extract Sr(Ⅱ)from nitrate media.TCHDGA was prepared and characterized by 1H nuclear magnetic resonance spectroscopy(NMR),^(13)C NMR,and fourier transform infrared spectroscopy(FT-IR).Various factors affecting extraction were studied systematically.In just 20 s,the extraction rate can reach approximately 98.2%.The extraction capacity of cyclohexyl-substituted extractant TCHDGA is tens of times higher than that with linear or branched chain alkyl.The chemical structure of the complex has been demonstrated to be[Sr3TCHDGA]·(NO_(3))_(2),based on FT-IR,X-ray photoelectron spectroscopy(XPS),and crystal structure analysis.The crystal belongs to the monoclinic system,space group P21,and a strontium ion coordinates with nine oxygen atoms,all of which contribute from TCHDGA.The stripping rate can reach over 99%when using distilled water or 0.50 mol·L^(-1)oxalic acid as stripping agents. 展开更多
关键词 STRONTIUM TCHDGA extractant extractION Crystal structure
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Solvent extraction systems for selective isolation of light rare earth elements with high selectivity for Sm and La
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作者 Hossein Salehi Samane Maroufi +1 位作者 Rasoul Khayyam Nekouei Veena Sahajwalla 《Rare Metals》 2025年第3期2071-2084,共14页
This study details a comprehensive approach focusing on the effective separation of light rare earth elements(REEs)via solvent extraction technique.A stock solution containing lanthanum,cerium,neodymium,praseodymium,a... This study details a comprehensive approach focusing on the effective separation of light rare earth elements(REEs)via solvent extraction technique.A stock solution containing lanthanum,cerium,neodymium,praseodymium,and samarium was prepared by dissolving their pure mixed oxide(reclaimed from spent Ni-MH batteries)in a diluted HCl solution.Key extractants,including bis(2,4,4-trimethylpentyl)phosphinic acid(Cyanex 272),Cyanex 572,trialkylphosphine oxide(Cyanex 923),and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester(PC 88A),along with tributyl phosphate(TBP)as a phase modifier,were utilized to form organic systems.The extraction behavior and separability of these systems at various pH levels as well as their extraction mechanisms were investigated.The results demonstrated a direct relationship between the extraction trend and the experimental pH value,with enhanced selectivity when TBP was added.Notably,Nd and Pr exhibited similar extraction behaviors,with minor deviations from Ce,making their separation difficult to achieve.Sm extraction followed a distinct trend,allowing for its separation from other elements at pH≤2.In contrast,La exhibited a low affinity for coordination with extractants when pH was≤3.5,facilitating the separation of other elements from La,which could then be isolated in the raffinate.Among the studied organic systems,combinations of Cyanex 572 and PC 88A with TBP demonstrated superior performance in element separation.Optimum separation factors were calculated withβ_(Ce/La)=12,βNd/La=87,β_(Pr/La)=127,andβ_(Sm/La)=3191 for the former,andβ_(Sm/Ce)=54,β_(Sm/Nd)=20,andβ_(Sm/Pr)=14 for the latter.These findings provide valuable insights for selecting extraction systems and designing experiments for the effective solvent extraction separation of light REEs from their mixture. 展开更多
关键词 Solvent extraction Rare earth elements Individual separation Ni-MH batteries extraction mechanism
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Synergistic solvent extraction system of bis(pyridin-2-ylmethyl)dodecan-1-amine and dinonylnaphthalene for enhanced selective extraction of nickel and cobalt
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作者 Bharat Prasad Sharma Tianzhang Wang +3 位作者 Yufeng Liang Jinping Xiong Liangrong Yang Zheng Li 《Chinese Journal of Chemical Engineering》 2025年第1期10-18,共9页
Simultaneous recovery of Ni and Co from Fe(Ⅲ)and AI is a critical challenge in hydrometallurgical processes.Recognized solvent extraction systems often struggle with selectivity and effective performance in mixed met... Simultaneous recovery of Ni and Co from Fe(Ⅲ)and AI is a critical challenge in hydrometallurgical processes.Recognized solvent extraction systems often struggle with selectivity and effective performance in mixed metal ion environments.Herein,a new synergistic solvent extraction(SSX)system comprised of a novel pyridine analog,N,N-bis(pyridin-2-ylmethyl)dodecan-1-amine(BPMDA),and dinonylnaphthalene sulfonic acid(DNNSA)with tributyl phosphate as phase modifier is introduced.The SSX system demonstrates high extraction performance achieving>90%for Ni and>97%for Co in a singlestage extraction process,with high selectivity.Under optimal conditions,the selectivity sequence is observed as Co^(2+)(>97%)>Ni^(2+)(>90%)>Mn^(2+)(<20%)>Fe^(3+)(<10%)>Mg^(2+)(<5%)>Al^(3+)(<2%)>Ca^(2+)(<1%).Spectroscopic analysis evidences the preferential binding of BPMDA with Ni and Co in the presence of DNNSA,concurrently achieving a significant reduction in the co-extraction of Fe(Ⅲ)and Al.The selective complexation of Ni and Co using the SSX system offers a highly efficient and selective approach for their extraction,with promising potential for applications in recovery-based processes. 展开更多
关键词 Nickel and cobalt extraction Synergistic solvent extraction DNNSA Pyridine HYDROMETALLURGY
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Comparative spectrum of antimicrobial activity of Phyllanthus emblica(Indian gooseberry)leaf extracts against clinically important pathogenic microbes in comparison to methanolic extracts of leaves of other plants
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作者 Bhoj Raj Singh Himani Agri +2 位作者 Akanksha Yadav Varsha Jayakumar Abhijit Motiram Pawde 《Infectious Diseases Research》 2025年第3期1-8,共8页
Background:Fruits of Indian gooseberry or Amla or Aonla(Phyllanthus emblica)are important ingredients in many Ayurvedic medicines,but little is known about its leaves.Methods:Different extracts and crude alkaloids of ... Background:Fruits of Indian gooseberry or Amla or Aonla(Phyllanthus emblica)are important ingredients in many Ayurvedic medicines,but little is known about its leaves.Methods:Different extracts and crude alkaloids of P.emblica leaves were evaluated for their antimicrobial activity against clinically important microbes using agar well diffusion assay.The antimicrobial activity of methanolic extract(ME)of P.emblica leaves was also compared with similarly prepared methanolic extracts from leaves of Yellow Kaner(Cascabela peruviana),Parijaat or Harsingar(Nyctanthes arbor-tristis),Custard apple(Annona squamosa),Garlic vine(Mansoa alliacea),Shami plant(Prosopis cineraria),Madar(Calotropis gigantea),and Bael(Aegle marmelos).Results:The ME of leaves of P.emblica was the most potent preparation against bacteria and yeast.Of the 338 strains of microbes belonging to 100 species(96 bacteria and four Candida species),the ME of P.emblica inhibited the growth of 300 strains.A total of 84.62%,96.39%,and 100%of 221 G−bacteria,111 G+bacteria,and 6 Candida species strains,respectively,were inhibited by ME of P.emblica leaves at≤36 mg/well.The aqueous extract of P.emblica leaves also inhibited a similar number of bacterial strains,but at higher concentrations,while the ether extract could inhibit only staphylococci.The alkaloid from P.emblica leaves and the ME from leaves of other plants had insignificant antimicrobial activity at similar≤36 mg/well concentration.Conclusion:The study concluded that the ME of P.emblica leaves may be a useful source of a potent,wide-spectrum antimicrobial substance(s). 展开更多
关键词 Emblica officinalis ether extract ALKALOID G+ve bacteria G−ve bacteria Candida species aqueous extract salmonella enterica ssp.enterica Escherichia coli Staphylococcus aureus
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Dual-hole extraction strategy promotes photoelectrochemical water splitting of bismuth vanadate photoanode
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作者 Hua Yang Dingyanyan Zhou +6 位作者 Kaige Tian Lingjiang Kong Pengfei An Jing Zhang Yujin Ji Youyong Li Junqing Yan 《Chinese Journal of Catalysis》 2025年第10期236-249,共14页
Elemental doping of BiVO_(4) crystal lattices effectively enhances carrier separation,thereby facilitating efficient photoelectrochemical water splitting.However,the positive effect of elementally induced lattice dist... Elemental doping of BiVO_(4) crystal lattices effectively enhances carrier separation,thereby facilitating efficient photoelectrochemical water splitting.However,the positive effect of elementally induced lattice distortions on hole extraction has been neglected.Herein,the crystal lattice of BiVO_(4) is distorted by doping with an inexpensive Cs metal;then,CoFe_(2)O_(4) is used as an efficient hole-extraction layer to further modify the surface of the doped photoanode.Benefiting from the above design,the newly prepared CoFe_(2)O_(4)-Cs-BiVO_(4) photoanode achieved a photocurrent density of 5.66 mA cm^(–2) at 1.23 V vs.a reversible hydrogen electrode,indicating a 3.9-fold improvement in photocurrent density.Detailed physicochemical characterization and density functional theory calculations showed that the lattice distortion induced by Cs doping promoted the directional migration of BiVO_(4) bulk-phase holes to the CoFe_(2)O_(4) layer.Additionally,the coupled CoFe_(2)O_(4) can be used as a hole extraction layer to further enhance the interfacial migration of carriers.The synergistic effect of the two effectively promotes the directional migration of photogenerated carriers from the BiVO_(4) bulk phase to the active sites of the oxygen evolution reaction,thereby effectively inhibiting carrier recombination.This study revealed the positive effect of the dual-hole extraction strategy on solar energy conversion,thereby opening new avenues for the rational design of photoanodes. 展开更多
关键词 Bismuth vanadate Photoelectrochemical water splitting Lattice distortion CoFe_(2)O_(4)hole extraction layer Dual-hole extraction
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Removal of chromium(Ⅲ) from aqueous waste solution by predispersed solvent extraction 被引量:1
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作者 罗建洪 李军 +1 位作者 杨兆鹏 刘雪峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期524-529,共6页
The extraction experiments of chromium(W) from aqueous waste solution by predispersed solvent extraction (PDSE) process with extractant (HEHPEHE) and its mixture, including acidic extractant (D2EHPA), alkaline... The extraction experiments of chromium(W) from aqueous waste solution by predispersed solvent extraction (PDSE) process with extractant (HEHPEHE) and its mixture, including acidic extractant (D2EHPA), alkaline extractant (TOA) and neutral extractant (TBP) were carried out respectively. It is found that the extractant HEHPEHE exhibited high extraction selectivity to chromium(III) from aqueous waste solution. The colloidal liquid aphrons (CLAs) were successfully generated using kerosene as a solvent, HEHPEHE as an extractant, sodium dodecyl benzene sulphate (SDBS) as a surfactant in aqueous phase and polyoxyethylene sorbitol anhydride monolaurate (Tween-20) in oil phase. To study the extraction efficiency and advantages of the PDSE process in the removal of chromium(III), the effects of major factors, such as initial chromium(III) concentration, volume of colloidal gas aphrons (CGAs), HEHPEHE volume fraction, phase ratio (solvent phase to water phase), mass fraction of dodecyl trimethylammonium bromide (HTAB), mass fraction of SDBS, mass fraction of Tween-20 and initial pH of aqueous waste solution were also investigated and the appropriate process conditions were obtained. Under the appropriate conditions, the extraction efficiency of chromium(III) above 99.9 % can be achieved and the treated aqueous waste solution can be discharged directly without polluting the environment. 展开更多
关键词 predispersed solvent extraction (PDSE) process chromium(III) extraction mechanism extractANT
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Extraction of the Residual Polycyclic Aromatic Hydrocarbons in the Long-term Contaminated Soil in the Field 被引量:1
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作者 张铁军 李晓军 +2 位作者 杨辉 王善仙 图影 《Agricultural Science & Technology》 CAS 2010年第9期153-156,共4页
[Objective] The aim of this study was to find a better method to exactly quantify the residual polycyclic aromatic hydrocarbons(PAHs)in the long-term contaminated soil in the field so as to provide basis for the rem... [Objective] The aim of this study was to find a better method to exactly quantify the residual polycyclic aromatic hydrocarbons(PAHs)in the long-term contaminated soil in the field so as to provide basis for the remediation for PAHs contaminated soil.[Method]The comparisons of soxhlet extraction,ultrasonic extraction and shaking extraction were studied in the agricultural soil irrigated with oil sewage over a long period of time.[Result]The total PAHs extracted by soxhlet extraction were the highest(6 873.7 μg/kg),followed by shaking extraction(6 698.8 μg/kg)and ultrasonic extraction(5 737.6 μg/kg).Among these methods,the highest extracted 4 and 6 rings PAHs were in the soxhlet extraction,the highest extracted 2 and 5 rings PAHs were in the shaking extraction,and the highest extracted 3 rings PAHs were in the ultrasonic extraction.[Conclusion]This study had provided basis for the selection of the assessment method of residual PAHs in the field soil. 展开更多
关键词 Polycyclic aromatic hydrocarbons Soil Soxhlet extraction Ultrasonic extraction Shaking extraction
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