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Vector Extraction from Design Drawings for Intelligent 3D Modeling of Transmission Towers
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作者 Ziqiang Tang Chao Han +5 位作者 Hongwu Li Zhou Fan Ke Sun Yuntian Huang Yuhang Chen Chenxing Wang 《Computers, Materials & Continua》 2025年第2期2813-2829,共17页
Accurate vector extraction from design drawings is required first to automatically create 3D models from pixel-level engineering design drawings. However, this task faces the challenges of complicated design shapes as... Accurate vector extraction from design drawings is required first to automatically create 3D models from pixel-level engineering design drawings. However, this task faces the challenges of complicated design shapes as well as cumbersome and cluttered annotations on drawings, which interfere with the vector extraction heavily. In this article, the transmission tower containing the most complex structure is taken as the research object, and a semantic segmentation network is constructed to first segment the shape masks from the pixel-level drawings. Preprocessing and postprocessing are also proposed to ensure the stability and accuracy of the shape mask segmentation. Then, based on the obtained shape masks, a vector extraction network guided by heatmaps is designed to extract structural vectors by fusing the features from node heatmap and skeleton heatmap, respectively. Compared with the state-of-the-art methods, experiment results illustrate that the proposed semantic segmentation method can effectively eliminate the interference of many elements on drawings to segment the shape masks effectively, meanwhile, the model trained by the proposed vector extraction network can accurately extract the vectors such as nodes and line connections, avoiding redundant vector detection. The proposed method lays a solid foundation for automatic 3D model reconstruction and contributes to technological advancements in relevant fields. 展开更多
关键词 Design drawings semantic segmentation deep learning vector extraction DIGITIZATION 3D modeling
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Salting-out Extraction of 2,3-Butanediol from Jerusalem artichoke-based Fermentation Broth 被引量:6
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作者 DAI Jianying ZHANG Yuanli XIU Zhilong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期682-686,共5页
The removal of solid impurities and separation of target products from a fermentation broth is becoming more tedious with the utilization of lignocelluloses as source of substrate.2,3-Butanediol,an important chemical ... The removal of solid impurities and separation of target products from a fermentation broth is becoming more tedious with the utilization of lignocelluloses as source of substrate.2,3-Butanediol,an important chemical used widely is also a main product of sugar-based fermentation carried out by Klebsiella pneumoniae.In this study,we investigated the use of salting-out extraction(SOE) that employed a K2HPO4/ethanol system consisting of 21% ethanol and 17% K2HPO4(mass fraction) to separate 2,3-butanediol from the viscous Jerusalem artichoke-based fermentation broth.After SOE,about 98% of solid matters was removed,and the viscosity decreased from 72.5 mPa s in the original fermentation broth to 4.4 mPa s in the top phase.The partition coefficient and yield of 2,3-butanediol reached 13.4 and 99%,respectively,and 89% of soluble proteins was removed from the broth.The results showed that SOE is an efficient way for isolating 2,3-BD from a highly viscous fermentation broth by removing much of the solid matters within the broth. 展开更多
关键词 2 3-butanediol Jerusalem artichoke salting-out extraction VISCOSITY
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Integrative Extraction of Ergosterol, (1→3)-α-D-Glucan and Chitosan from Penicillium chrysogenum Mycelia 被引量:11
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作者 王天奇 李翰祥 +1 位作者 王满意 谭天伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期725-729,共5页
Abstract Ergosterol,(1→3)-α-D-glucan and chitosan are important biomaterials. In this research, a process has been developed to integratively extract ergosterol, (1→3)-α-D-glucan, and chitosan from Penicillium... Abstract Ergosterol,(1→3)-α-D-glucan and chitosan are important biomaterials. In this research, a process has been developed to integratively extract ergosterol, (1→3)-α-D-glucan, and chitosan from Penicillium chrysongenum mycelium. First the mycelia are pretreated with 0.1mol·L^-1 of NaOH. After recovery by centrifugation the solid portion is made to undergo saponification and deacetylation reactaons by addition of 2mol·L^-1 NaOH and et anol.After reaction, extraction is carried out by addition of petroleum ether, which separates the reaction mixture into two phases. The upper layer of petroleum ether contains extracted ergosterol, and the .bottom layer of NaOH solution contains (1→3)-α-DEglucan; the chitosan is on the mycelia residuum. After isolation, the recovery yield of ergosterol is 0.52% of dry mycelium. That of (1→3)-α-D-glucan is about 8.2%; and chitosan is 5.7% with 86% deacetylation. The compositions have been characterized by 1R, HPLC analyses. 展开更多
关键词 ERGOSTEROL (1→3)-α-D-glucan CHITOSAN extraction Penicillium chrysogenum
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Extraction of rare earth elements from their oxides using organophosphorus reagent complexes with HNO_3 and H_2O in supercritical CO_2 被引量:5
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作者 段五华 曹丕佳 朱永(贝睿) 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第2期221-226,共6页
Direct extraction of metals from solids with complexing agents in supercritical CO2(SC-CO2) has recently attracted interests in separation,purification,recovery,and analysis of metals.In the present study,the static/d... Direct extraction of metals from solids with complexing agents in supercritical CO2(SC-CO2) has recently attracted interests in separation,purification,recovery,and analysis of metals.In the present study,the static/dynamic extraction of rare earth elements(Nd,Ce) from their oxides(Nd2O3,CeO2) with organophosphorus complexes with HNO3 and H2O in SC-CO2 was investigated.The static extraction efficiency of Nd from Nd2O3 with the tri-n-butylphosphate(TBP)-HNO3 complex could reach 95% under optimized experiment... 展开更多
关键词 supercritical CO2 TBP-HNO3 complex TRPO-HNO3 complex extraction rare earths
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Extraction Behavior of Rare Earths with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 Using Solid-liquid Extraction Technique 被引量:2
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作者 高锦章 潘仲巍 +2 位作者 杜新贞 康敬万 白光弼 《Rare Metals》 SCIE EI CAS CSCD 1993年第3期198-202,共5页
The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium... The extraction behavior of rare earths was studied by using paraffin with ceresin as a diluent containing 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5.In solid phase,the composition of complexes is REP_3.The equilib- rium extraction constants and pH_(1/2) values of solid-liquid extraction are higher than those of normal liquid-liquid extraction.The extraction efficiency tends to maximum when the ratio of phases is 1:1.When the extraction temperature is higher than the melting point of paraffin and the extraction time is over 10 min,the extraction efficiency keeps constant.Moreover,the relationship among separation factor,equilibrium extrac- tion constant,pH_(1/2) value and atomic number was obtained.The mechanism of solid-liquid extraction is analogous to that of liquid-liquid extraction. 展开更多
关键词 Solid-liquid extraction Rare earths 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5
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Kinetics of Reactive Extraction of Nd from Nd2O3 with TBP-HNO3 Complex in Supercritical Carbon Dioxide 被引量:3
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作者 朱礼洋 段五华 +1 位作者 徐景明 朱永 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期214-218,共5页
The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generat... The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generation of secondary waste.Dynamic reactive extraction of neodymium oxide(Nd2O3) in supercritical carbon dioxide(SC-CO2) containing tri-n-butyl phosphate-nitric acid(TBP-HNO3) complex was investigated.Temperature showed a positive effect on the extraction efficiency,while pressure showed a negative effect when the unsaturated TBP-HNO3 complex was employed for the dynamic reactive extraction of Nd2O3 in SC-CO2.Both temperature and pressure effects indicated that the kinetic process of the reactive extraction was controlled by the chemical reaction.A kinetic model was proposed to describe the extraction process. 展开更多
关键词 supercritical carbon dioxide KINETICS reactive extraction TBP-HNO3 complex ND2O3
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Extraction of palladium(Ⅱ) from hydrochloride solutions with 2-n-octyl-4-isothiazolin-3-one as novel extractant 被引量:1
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作者 Song-Ping Wu 《Rare Metals》 SCIE EI CAS CSCD 2013年第4期425-430,共6页
Solvent extraction of palladium (Ⅱ) from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one (OIT)/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.9... Solvent extraction of palladium (Ⅱ) from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one (OIT)/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium (Ⅱ) could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium (Ⅱ) from the loaded organic phase was achieved with 0.5 mol·L^-1 (NH2)2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra. 展开更多
关键词 Solvent extraction PALLADIUM 2-n-octyl-4-isothiazolin-3-one OIT STRIPPING
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Effective and simple recovery of 1,3-propanediol from a fermented medium by liquid–liquid extraction system with ethanol and K_3PO_4 被引量:4
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作者 Daiana Wischral Hongxin Fu +2 位作者 Fernando L.Pellegrini Pessoa Nei Pereira Jr Shang-Tian Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第1期104-108,共5页
1,3-Propanediol,traditionally obtained from fossils,has numerous industrial applications,including use in the production of high performance polymers.The microbial production of 1,3-propanediol presents several opport... 1,3-Propanediol,traditionally obtained from fossils,has numerous industrial applications,including use in the production of high performance polymers.The microbial production of 1,3-propanediol presents several opportunities,and the final purity grade determines its price and commercial viability.The development of novel separation technology could improve the economic viability of the bioproduction of 1,3-propanediol.Thus,we investigated salting-out extraction as a novel process for 1,3-propanediol recovery from fermentation broth.Initially,a screening for the best salt/solvent combination was conducted and then optimized using the response surface methodology.The solvents studied were methanol,ethanol,isopropanol and acetone,and the salts examined were K_2HPO_4,Na_2CO_3,K_2CO_3,(NH_4)_2SO_4,NaHPO_4,K_3PO_4 and C_6H_5NaO_7.The optimal extraction system consisted of 34 wt%K_3PO_4,28 wt% ethanol,and 38 wt% fermentation broth containing 23.0 g·L^(-1)1,3-propanediol,which gave the highest partition coefficient of 33 and recovery yield of 97%.The results demonstrated that salting-out extraction was a promising method for 1,3-propanediol recovery from fermentation broth. 展开更多
关键词 Fermentation Downstream process 1 3-Propanediol Clostridium beijerinckii Liquid-liquid extraction Salting-out extraction
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Extraction of lanthanide ions with N,N,N′,N′-tetrabutyl-3-oxadiglycolamide from nitric acid media 被引量:1
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作者 Xiu-Jing Peng Yu Cui +2 位作者 Ji-Fei Ma Yulan Li Guo-Xin Sun 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第6期190-195,共6页
Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDG... Extractability and extraction mechanism of lanthanide ions were investigated by using a new extractant,N,Nn,N′,N′-tetrabutyl-3-oxa-diglycolamide(TBDGA),in toluene from nitric acid media.The effects of HNO_3 and TBDGA concentrations,and temperature,on extraction of lanthanide ions were studied.Stoichiometrics of the main extracted species were HNO_3·TBDGA and M(NO_3)_3-3TBDGA(M = Er,Dy,Tb,Gd,La,Ce,Nd,Sm and Eu).The extracted species for metal ions were established to be ionic complex.In this complex,nitrate anion was not coordinated to the central ion.The extraction pattern increased gradually across the lanthanide ions series,showing enhanced affinity of TBDGA toward heavy lanthanide ions.Thermodynamic parameters were investigated for the exothermic extraction reaction. 展开更多
关键词 Lanthanide ions extraction N N N N-tetrabutyl-3-oxa-diglycolamide NITRIC acid TOLUENE
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Kinetic study on selective extraction of HCl and H_3PO_4 in a microfluidic device 被引量:2
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作者 Fang Zhao Yangcheng Lu +1 位作者 Kai Wang Guangsheng Luo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期221-225,共5页
In the extraction method for preparing KH2PO4, one of the key processes is the selective extraction of HCI over H3PO4. In our work, extraction kinetic studies have been carried out in a microfluidic device with a coax... In the extraction method for preparing KH2PO4, one of the key processes is the selective extraction of HCI over H3PO4. In our work, extraction kinetic studies have been carried out in a microfluidic device with a coaxial microchannel, using the extractant of 33.3% (by volume) trioctylamine (TOA) dissolved in n-octanol, with differ- ent aqueous phases: the HCI solution, the H3P04 solution, and H3PO4 and KCI solutions of different concentra- tions. The changes of the extraction efficiency of HC1 and H3P04 and the selectivity for HC1 along with the residence time were investigated. We found that fast extraction kinetics could be realized in microfluidic devices, and that HC1 could be extracted faster than H3P04 due to smaller mass transfer resistance and much stronger re- action between HCI and TOA. For the extraction of H3PO4 and KC1 solutions, the selectivity for HC1 first increased and then decreased when TOA was in excess of H3PO4 in the initial feeds, and in contrast, always increased when H3PO4 was in excess of TOA in the initial feeds. The diverse changes of selectivity for HCI along with the residence time indicate that a dynamic control of selectivity in microfluidic devices may be important and accessible for im- proving the KH2P04 conversion efficiency in extraction method. 展开更多
关键词 KINETICS Selective extraction MICROCHANNEL TOA HCI H3PO4
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Multi-walled carbon nanotube as a solid phase extraction adsorbent for analysis of indole-3-butyric acid and 1-naphthylacetic acid in plant samples 被引量:4
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作者 Zong-Hua Wang Jian-Fei Xia +4 位作者 Qiang Han Hai-Ning Shi Xin-Mei Guo Hui Wang Ming-Yu Ding 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第7期588-592,共5页
In this work, a new sample pretreatment method prior to HPLC separations was developed for the determination of auxins in plant samples, Owing to its large surface area and high adsorption capacity, multi-walled carbo... In this work, a new sample pretreatment method prior to HPLC separations was developed for the determination of auxins in plant samples, Owing to its large surface area and high adsorption capacity, multi-walled carbon nanotube (MWCNT) was chosen as the adsorbent for the extraction of auxins from plant samples. In this study, two important auxins were selected as model analytes, namely indole-3- butyric acid (IBA) and 1-naphthylacetic acid (NAA). They could be extracted and concentrated due to their π-π stacking interactions with MWCNT. Then HPLC-UV was introduced to detect IBA and NAA after sample pretreatment. Factors that may affect the enrichment efficiency were investigated and optimized. Comparative studies showed that MWCNT was superior to CI 8 for the extraction of the two analytes. Validation experiments showed that the optimized method had good linearity (0.9998 and 0.9960), high recovery (81.4%-85.4%), and low detection limits (0.0030 mg/L and 0.0012 mg/L). The results indicated that the novel method had advantages of convenience, good sensitivity, high efficiency, and it was feasible for the determination of auxins in plant samples. 展开更多
关键词 Multi-walled carbon nanotube Solid phase extraction Indole-3-butyric acid 1-Naphthylacetic acid
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Facile preparation of nano-g-C_(3)N_(4)/UiO-66-NH_(2) composite as sorbent for high-efficient extraction and preconcentration of food colorants prior to HPLC analysis 被引量:6
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作者 Xiaowan Zhang Yixin Yang +5 位作者 Peige Qin Lizhen Han Wenli Zhu Shaofeng Duan Minghua Lu Zongwei Cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第2期903-906,共4页
In this work,the nano-g-C_(3)N_(4)/Ui O-66-NH_(2)composite was prepared by one-step solvothermal method.The as-prepared composite was characterized by scanning electron microscopy,Brunner-Emmet-Teller measurement,ener... In this work,the nano-g-C_(3)N_(4)/Ui O-66-NH_(2)composite was prepared by one-step solvothermal method.The as-prepared composite was characterized by scanning electron microscopy,Brunner-Emmet-Teller measurement,energy dispersive spectrometer,X-ray diffraction,and Fourier transform infrared spectroscopy.By using nano-g-C_(3)N_(4)/Ui O-66-NH_(2)composite as sorbent,a dispersive solid-phase extraction coupled with high-performance liquid chromatography was developed to sensitive analysis of food colorants including tartrazine,amaranth,carmine,sunset yellow,allura red and bright blue.The experiment parameters including the amount of sorbent,adsorption time,the p H of adsorption solution,desorption time,desorption solvent,the p H of desorption solution as well as the proportion between desorption solvent and buffer solvent were investigated.Under the optimized conditions,the limits of detection(S/N=3) and limits of quantitation (S/N=10) were determined in the ranges of 0.08-0.8 and 0.2-2.0 ng/m L,respectively.With the developed sample pretreatment method,carmine and brilliant blue were determined from blueberry juice by HPLC-DAD.The contents were calculated as 1.53μg/m L and0.17μg/mL,respectively. 展开更多
关键词 Nano-g-C_(3)N_(4)/Ui O-66-NH_(2)composite Metal-organic frameworks Dispersive solid-phase extraction Sample pretreatment Food colorants Food additives High-performance liquid chromatography
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Detection of Tetracycline Antibiotics in Water by Dispersive Micro-solid Phase Extraction using Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]Magnetic Composite Combined with Liquid Chromatography-Tandem Mass Spectrometry 被引量:2
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作者 Yan-ni Li Yan-yun Hu +2 位作者 Lei Ding Dian-bing Zhou Wen-jun Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第2期238-248,I0002,共12页
Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analys... Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analysis.In this work,a magnetic metal-organic framework Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]was synthesized and applied as a dispersive micro-solid phase extraction adsorbent for TCs enrichment.Effects of dispersive micro-solid phase extraction conditions including extraction time,solution p H,and elution solvent on the extraction efficiencies of TCs were investigated.Results show that TCs could be enriched efficiently by Fe_(3)O_(4)@[Cu_(3)(btc)_(2)],and electrostatic interaction between TCs and Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]dominated this process.Combined with liquid chromatography-tandem mass spectrometry,four TCs residues (oxytetracycline,tetracycline,chlortetracycline,and doxycycline) in natural waters were determined.The detection limits (LOD,S/N=3) of the four antibiotics were 0.01-0.02μg/L,and the limits of quantitation (LOQ,S/N=10)were 0.04-0.07μg/L.The recoveries obtained from river water and aquaculture water spiked with three TCs concentration levels ranged from 70.3%to 96.5%with relative standard deviations of 3.8%-12.8%.Results indicate that the magnetic metal-organic framework based dispersive micro-solid phase extraction is simple,rapid and high-loading for antibiotics enrichment from water,which further expand the practical application of metal-organic frameworks in sample pretreatment for environmental pollutant analysis. 展开更多
关键词 Fe_(3)O_(4)@[Cu_(3)(btc)_(2)] Metal-organic frameworks Dispersive micro-solid phase extraction Tetracycline
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Analysis of anticancer compound,indole-3-carbinol,in broccoli using a new ultrasound-assisted dispersive-filter extraction method based on poly(deep eutectic solvent)-graphene oxide nanocomposite 被引量:1
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作者 Yanan Yuan Huanhuan Chen +2 位作者 Yehong Han Fengxia Qiao Hongyuan Yan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第2期301-307,共7页
Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challengin... Indole-3-carbinol(I3C),an important anticancer compound found in broccoli,has attracted considerable attention.The rapid extraction and accurate analysis of I3C in the pharmaceutical industry in broccoli is challenging as I3C is unstable at low pH and high temperature.In this study,a rapid,accurate,and lowcost ultrasound-assisted dispersive-filter extraction(UADFE)technique based on poly(deep eutectic solvent)-graphene oxide(PDES-GO)adsorbent was developed for the isolation and analysis of I3C in broccoli for the first time.PDES-GO with multiple adsorption interactions and a fast mass transfer rate was synthesized to accelerate adsorption and desorption.UADFE was developed by combining dispersive solid-phase extraction(DSPE)and filter solid-phase extraction(FSPE)to realize rapid extraction and separation.Based on the above two strategies,the proposed PDES-GO-UADFE method coupled with high-performance liquid chromatography(HPLC)allowed the rapid(15-16 min),accurate(84.3%-96.4%),and low-cost(adsorbent:3.00 mg)analysis of I3C in broccoli and was superior to solid-phase extraction,DSPE,and FSPE methods.The proposed method showed remarkable linearity(r=0.9998;range:0.0840-48.0 mg/g),low limit of quantification(0.0840 mg/g),and high precision(relative standard deviation<5.6%).Therefore,the PDES-GO-UADFE-HPLC method shows significant potential in the field of pharmaceutical analysis for the separation and analysis of anti-cancer compounds in complex plant samples. 展开更多
关键词 INDOLE-3-CARBINOL BROCCOLI Poly(deep eutectic solvent)-graphene oxide Ultrasound-assisted dispersive-filter extraction Rapid analysis
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Thermodynamic and application study of complicated extraction system Ce(Ⅳ)-HF-H_(3)BO_(3)-H_(2)SO_(4) using Cyanex 923 被引量:1
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作者 Dan Zou Haitian Li +1 位作者 Ji Chen Deqian Li 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第9期1117-1125,共9页
This article aims to reduce the environmental pollution while maximizing the recovery of REEs as well as associate resource-fluorine(F)from bastnaesite.This paper investigates the extraction equilibrium process and me... This article aims to reduce the environmental pollution while maximizing the recovery of REEs as well as associate resource-fluorine(F)from bastnaesite.This paper investigates the extraction equilibrium process and mechanism of Ce(Ⅳ)-HF-H_(3)BO_(3)-H_(2)SO_(4)system using Cyanex 923.Extraction equilibrium process of different systems,including HF-H_(2)SO_(4),H_(3)BO_(3)-HF-H_(2)SO_(4),and Ce(Ⅳ)-HF-H_(2)SO_(4),were studied in detail and the corresponding extraction mechanisms were also determined.It is noteworthy that a synergistic effect between B-F and an antagonistic effect between Ce(Ⅳ)-F were discovered first in the extraction process by Cyanex 923.Besides,H_(3)BO_(3)is found to be able to promote the extraction of F in quantitation by Cyanex 923.FTIR and^(11)B and^(19)F NMR were adopted to characterize the different loaded organic phase.Based on these results,the extraction mechanism of complicated system Ce(Ⅳ)-HF-H_(3)BO_(3)-H_(2)SO_(4)was further determined.Besides,the effect of H_(3)BO_(3)on the extraction and stripping of Ce(Ⅳ)in complicated system was studied.Moreover,it shows that the addition of H_(3)BO_(3)has nothing to do with the purity of obtained CeF_(3)particle from bastneasite liquor in the practical system.Adding H_(3)BO_(3)into bastnaesite leach liquor,on the one hand,will be beneficial for the recovery yield of Ce and F.On the other hand,it can avoid from environmental pollution caused by emission of F-containing waste water as well as reducing the waste residue. 展开更多
关键词 Ce(Ⅳ)-HF-H_(3)BO_(3)-H_(2)SO_(4) extraction Cyanex 923 THERMODYNAMIC Mechanism Rare earths
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Effect of Crystallinity on Electrochemical Insertion/Extraction of Li in Transition Metal Oxides Part Ⅱ: TiO_2, V_2O_5 and MoO_3 被引量:1
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作者 Tomoki TSUMURA and Michio INAGAKI (Graduate School of Engineering, Hokkaido University Kita-ku, Sapporo, 060-8628, Japan) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第1期5-14,共10页
Electrochemical insertion/extraction of Li on cathode materials of anatase type TiO_2, quasilayered structure V_2O_5 and layered structure MoO_3 was measured on samples of which structures were well characterized and... Electrochemical insertion/extraction of Li on cathode materials of anatase type TiO_2, quasilayered structure V_2O_5 and layered structure MoO_3 was measured on samples of which structures were well characterized and showed a wide range of crystallinity. On the basis of experimental results on structure, morphology and charge-discharge characteristics, the effect of crystallinity of the cathode materials on electrochemical Li insertion/extraction pedermance was discussed. These three transition metal oxides were classified as one group on the basis of whether the crystallinity of these oxides affects to the performance or not; LiMn_2O_4 and LiCo_(0.5)O_2 belongs to the former group and TiO_2, V_2O_5 and MoO_3 to the latter. 展开更多
关键词 LI Effect of Crystallinity on Electrochemical Insertion/extraction of Li in Transition Metal Oxides PART V2O5 and MoO3
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A strategy for selective extraction of lanthanides based on self-assembly with MPyEDChDGA from nitric acid solution
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作者 Miaomiao Zhang Zhen Yang +5 位作者 Heng Zhao Chengjin Xu Xiaolei Liu Guoxin Sun Xiujing Peng Yu Cui 《Journal of Rare Earths》 2025年第9期1955-1963,共9页
The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycola... The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements. 展开更多
关键词 Rare earths extraction SELF-ASSEMBLY SEPARATION HNO_(3)
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EXTRACTION KINETICS,SYNERGISTIC EFFECTS AND INTERFACIAL CHEMISTRY FOR D_2 EHPA MPA-Fe^(3+) MIXED EXTRACTION SYSTEM
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作者 YU Jingfen LIU Difei Tsinghua University,Beijing,China professor,Dept.of Chemical Engineering,Tsinghua University,Beijing 100084,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1993年第12期405-410,共6页
The thermodynamics of micella formation,interfacial characteristics,synergistic effects and interfacial kinetics for synergistic extraction system D_2 EHPA-MPA-Fe^(3+) have been studied.It was found that D_2EHPA in th... The thermodynamics of micella formation,interfacial characteristics,synergistic effects and interfacial kinetics for synergistic extraction system D_2 EHPA-MPA-Fe^(3+) have been studied.It was found that D_2EHPA in the mixed system strongly exhibits the effect on the micella formation thermodynamics and interracial characteristics of MPA.Some ther- modynamic parameters for constants of micelles formation(K_m).free energies of micelles formation(ΔG_m)and critical micella concentrations(CMC)were obtained.The inter- facial adsorption behaviour of D_2EHPA is opposite to that of MPA.The emulsification for single MPA and the mixed system was discussed.The synergistic effects were found in this mixed extraction system.It is proved that the process of the Fe^(3+) extraction for non-mixed extraction system is controlled by chemical reaction and the controlling reaction occurs at the interface. 展开更多
关键词 interfacial chemistry synergistic effect Fe^(3+) extraction kinetics
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Synthesis of N,N'-dimethyl-N,N'-didecyl-3-oxa-diglycolamide for extraction of lanthanides 被引量:1
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作者 张辽宁 王亚群 +3 位作者 孙国新 周鹤方 党庆毅 崔玉 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第4期24-27,共4页
A novel extractant,N,N'-dimethyl-N,N'-didecyl-3-oxa-diglycolamide(DMDDDGA),was designed and synthesized for extraction of lanthanides in the nuclear fuel reprocessing.The extraction behaviors of Gd,Dy,Er and H... A novel extractant,N,N'-dimethyl-N,N'-didecyl-3-oxa-diglycolamide(DMDDDGA),was designed and synthesized for extraction of lanthanides in the nuclear fuel reprocessing.The extraction behaviors of Gd,Dy,Er and Ho from nitric acid solution were investigated using DMDDDGA in chloroform.The effects of nitric acid concentration,extractant concentration,and temperature on the extraction were investigated.The distribution ratio of lanthanides increases with concentrations of the extractant and nitric acid,but decreases with increasing temperature,which indicates that the extraction process is exothermic.FT-IR spectra indicated that the C=0 in DMDDDGA is coordinated with metal ion in the extracted species and the stoichiometries of lanthanides(Ⅲ)complex are Gd(NO_3)_3·3DMDDDGA,Dy(NO_3)_3·4DMDDDGA,Er(NO_3)_3·4DMDDDGA,and Ho(NO_3)_3·4DMDDDGA. 展开更多
关键词 镧系元素 提取过程 二甲基 合成 核燃料后处理 硝酸溶液 温度升高
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Analysis of the Results of Rectal Cancer Treatment via 3D Laparoscopic Natural Orifice Specimen Extraction Surgery (NOSES IV) 被引量:1
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作者 Bei Ma 《Journal of Clinical and Nursing Research》 2022年第5期30-34,共5页
Objective:To investigate the effect of 3D laparoscopic natural orifice specimen extraction surgery as rectal cancer treatment.Methods:The study was carried out in Shaanxi Provincial People’s Hospital from July 2021 t... Objective:To investigate the effect of 3D laparoscopic natural orifice specimen extraction surgery as rectal cancer treatment.Methods:The study was carried out in Shaanxi Provincial People’s Hospital from July 2021 to July 2022.80 rectal cancer patients were selected and divided into two groups which are the experimental group and control group.The experimental group was given 3D laparoscopic surgery while the control group was given 2D laparoscopic surgery.The results were compared and analysed.Results:The patients in the experimental group had shorter operative and evacuation times,less intraoperative bleeding,and a lower rate of complications.Conclusion:The clinical application of 3D laparoscopic radical surgery for rectal cancer via natural lumen extraction is more effective,which can promote patients'recovery and reduce the incidence of adverse events. 展开更多
关键词 3D laparoscopy Natural orifice specimen extraction surgery Rectal cancer Clinical outcome
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