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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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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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Contributions from the extractive industry to the understanding,identification,and conservation of geoheritage in UNESCO Global Geoparks
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作者 Silas Samuel dos Santos Costa Manu Monge-Ganuzas +1 位作者 Diamantino Insua Pereira Marcos Antonio Leite do Nascimento 《Episodes》 2025年第4期403-420,共18页
Resource extraction and nature conservation are often seen as opposing concepts.Traditionally,from the viewpoint of nature conservationists,they are only positively associated when rehabilitation efforts are made to r... Resource extraction and nature conservation are often seen as opposing concepts.Traditionally,from the viewpoint of nature conservationists,they are only positively associated when rehabilitation efforts are made to restore biodiversity in degraded lands due to extractive activities.Despite these conflicting relationships,in UNESCO Global Geoparks(UGGps),mining and quarrying can act as opening windows in the Earth’s surface exposing geoheritage. 展开更多
关键词 restore biodiversity nature conservation resource extraction GEOHERITAGE extractive industry unesco global geoparks uggps mining quarrying UNESCO Global Geoparks
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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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Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel 被引量:1
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作者 Lou Zhang Shuo Li +4 位作者 Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang Lidong Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期504-514,共11页
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are... Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings. 展开更多
关键词 silver nanoparticles HYDROGEL STRAW extraction ANTIBACTERIAL
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Prediction of dispersed phase holdup in pulsed disc and doughnut solvent extraction columns under different mass transfer conditions 被引量:3
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作者 Yong Wang Kathryn H.Smith +3 位作者 Kathryn Mumford Teobaldo F.Grabin Zheng Li Geoffrey W.Stevens 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期226-231,共6页
Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is present... Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns (PDDC) have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDC has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDC were used to refit constants for the correlation presented by Kumar and Hartland lind. Eng. Chem. Res.,27 (1988),131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDC (i.e. the plate spacing), the unified cor- relation for holdup proposed by Kumar and Hartland based on data from eight different types of columns [Ind. Eng. Chem. Res.,34 (1995) 3925-3940] was refitted to the PDDC data. New constants have been presented for each hold- up correlation for a PDDC based on regression analysis using published holdup data from PDDCs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer. 展开更多
关键词 Solvent extraction Liquid extraction Pulsed disc and doughnut columns Solvent extraction column design Holdup Dispersed phase holdup Hydrodynamics of extraction columns
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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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Construction of a Maritime Knowledge Graph Using GraphRAG for Entity and Relationship Extraction from Maritime Documents 被引量:1
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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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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals Water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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