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Optimization of Ultrasound-assisted Extraction Conditions for Polysaccharides from Pinus tabulaeformis Seed Shells
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作者 蒋龙 杨国庆 +2 位作者 杨鹏 刘伟 张大伟 《Agricultural Science & Technology》 CAS 2013年第12期1826-1829,共4页
[Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted fr... [Objective] This study aimed to investigate the optimal technological condi- tions for ultrasouqd-assisted extraction of polysaccharides from Pinus tabulaeformis seed shells. [Melhod] Polysaccharides were extracted from P. tabulaeformis seed shells by ultrasound-assisted hot water extraction method and detected by phenol- concentrated sulfuric acid method. The effect of extraction temperature, extraction duration, solid-liquid ratio and extraction frequency on the extraction of polysaccha- rides was investigated using single-factor gradient experiment and the extraction conditions for polysaccharides from P. tabulaeformis seed shells were optimized us- ing L9(34) orthogonal design. [Result] The content of polysaccharides extracted twice at 60 ℃ for 25 min with solid-liquid ratio of 1:3.5 reached the maximum. The re- covery rate (n=-5) ranged from 97.71% to 100.67% and RSD was 1.56%, suggesting high stability. [Conclusion] A simple and efficient method for ultrasound-assisted ex- traction of polysaccharides from P. tabulaeformis seed shells was established in this study, which laid solid foundation for the development and utilization of abandoned pine nut shell resources. 展开更多
关键词 ultrasound-assisted extraction Spectrophotography Pinus tabulaeformis seed shells Polvsaccharides
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Optimized Ultrasound-assisted Extraction of Proacyanidins from Purple Cabbage 被引量:2
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作者 栾娜 刘行 《Agricultural Science & Technology》 CAS 2013年第3期512-515,519,共5页
[Objective] The paper was to optimize ultrasound-assisted extraction of proacyanidins from purple cabbage. [Method] The ultrasound-assisted extraction technology was used to study the extraction of proacyanidins from ... [Objective] The paper was to optimize ultrasound-assisted extraction of proacyanidins from purple cabbage. [Method] The ultrasound-assisted extraction technology was used to study the extraction of proacyanidins from purple cabbage. The effect of ethanol concentration, temperature, time, material-solution ratio and the power of ultrasound on extracting efficiency were studied by single-factor experiment. Based on this, L16(4%orthogonal test were conducted to determine the optimal condi- tion for extraction of proacyanidins from purple cabbage. [Result] The optimal condi- tion for extraction of proacyanidins from purple cabbage was as follows: ethanol concentration 50%, extraction temperature 50℃, extraction time 1 h, extraction power 540 W, material-liquid ratio 1:20. The extraction rate of procyanidins under this condition reached 104.8 mg/g. [Conclusion] The study provided a theoretical basis for scientific and reasonable utilization of procyanidins in purple cabbage. 展开更多
关键词 Purple cabbage Proacyanidins ULTRASOUND extraction
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Effects of Ethanol Condensation Reflux Extraction and Ultrasound-assisted Extraction on the Content of Total Flavonoids of Pueraria edulis
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作者 Jun TANG Jianguang ZENG +1 位作者 Hao LI Chenzhong JIN 《Agricultural Biotechnology》 CAS 2023年第2期91-95,104,共6页
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex... With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%. 展开更多
关键词 Pueraria edulis Total flavonoids Condensation reflux extraction method ultrasound-assisted extraction
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Optimization of ultrasound-assisted extraction of camptothecin from Camptotheca acuminata seeds 被引量:2
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作者 JING Li-jia LI Si-yang CHANG Zui WANG Yang YAN Xiu-feng 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期239-242,共4页
Naturally occurring camptothecin(CPT) is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present... Naturally occurring camptothecin(CPT) is an important source of chemotherapeutic agents.The extraction from Camptotheca acuminata is still the main approach to obtain CPT compared with total synthesis.In the present study,ultrasound-assisted extractions(UAE) of CPT from C.acuminata seeds with alkaline solutions were investigated and CPT yield were determined by High Performance Liquid Chromatography.The conditions of alkaline species and concentrations,extraction time,extraction temperature and ultrasonic power were optimized.Results show that both Na3PO4 and Na2CO3 solutions gain good extraction yields,whereas Na3PO4 solution has stronger basicity and need higher concentration than Na2CO3 solution does,thus aqueous Na2CO3 is more beneficial for the extraction.The optimal condition was ultrasonically extracted with 0.5% aqueous Na2CO3 at 50°C and ultrasonic power of 400 W for 60 min.Comparing with UAE with ethanol,the extraction with 0.5% Na2CO3 solution achieves higher yield.Moreover,aqueous Na2CO3 as a solvent has various advantages including non-toxicity,inflammable,non-corrosive and low cost,which ensure this UAE method is a superior method with high utilizing prospect. 展开更多
关键词 CAMPTOTHECIN Camptotheca acuminata ultrasound-assistant extraction
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Study on the Technological Conditions of Ultrasound-assisted Extraction of Polysaccharides from Ajuga ciliata Bunge (Fujian) 被引量:1
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作者 Wenwen LU Ruonan HE +3 位作者 Zhongwei CHEN Chao YI Zhuangyu ZHANG Yanyan ZHENG 《Medicinal Plant》 CAS 2021年第1期51-55,共5页
[Objectives]To determine the optimum technological conditions of ultrasound-assisted extraction of polysaccharides from Ajuga ciliata Bunge.[Methods]In this study,Ajuga ciliata Bunge was used as raw material,and an or... [Objectives]To determine the optimum technological conditions of ultrasound-assisted extraction of polysaccharides from Ajuga ciliata Bunge.[Methods]In this study,Ajuga ciliata Bunge was used as raw material,and an orthogonal experiment was designed based on the single factor experiment to investigate the effects of ultrasonic time,solid-liquid ratio,ultrasonic temperature and ultrasonic power on the extraction rate of polysaccharides from A.ciliata Bunge(Fujian).Range analysis,variance analysis and SSR test of significant differences between groups were carried out with SPSS 20.0,and the test results were verified.[Results]Under the conditions of ultrasonic temperature of 85℃,ultrasonic time of 80 min,solid-liquid ratio of 1∶15 g/mL and ultrasonic power of 500 W,the yield of polysaccharides from A.ciliata Bunge(Fujian)was the best.[Conclusions]This study can provide theoretical basis for the application of A.ciliata Bunge(Fujian). 展开更多
关键词 Ajuga ciliata Bunge POLYSACCHARIDE Ultrasonic extraction Orthogonal test
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Effect of Ultrasound-Assisted Extraction of Phenolic Compounds on the Characteristics of Walnut Shells
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作者 Hannah Han Shusheng Wang +3 位作者 Milan Rakita Yanting Wang Qingyou Han Qin Xu 《Food and Nutrition Sciences》 2018年第8期1034-1045,共12页
Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially ... Walnuts are one of nature’s more waste-heavy products. 67% of the nut is shell and husk, low value by-products that are rich in phenolic compounds. The phenolic compounds extracted from walnut shells are potentially good natural sources of antioxidants for the food and pharmaceutical industries. In this study, phenolic compounds were extracted using an ultrasonic bath, an ultrasonic probe and a standard shaking method. The extraction yield achieved with an ultrasonic probe was 51.2 mg GAE/g DW, two times higher than both the shaking method and the ultrasonic bath method which were 20.6 mg GAE/g DW and 25.8 mg GAE/g DW, respectively. Phenolic extraction was further improved by a size reduction of the walnut shells. The best extraction yield of 52.8 mg GAE/g DW was attained when the particle size was between 45 - 100 mesh. The ultrasonic probe treatment is the best method for extraction of phenolic compounds from walnut shells. Scanning electron microscopy (SEM) imaging indicated that the ultrasonic probe treatment could better rupture the hard structure of the cells, increasing the penetration of solvents and thus the extraction yield. 展开更多
关键词 WALNUT SHELL ultrasound-assisted extraction TOTAL PHENOLIC Content (TPC) Particle Size SEM Analysis
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Ultrasound-assisted extraction of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety)husk
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作者 Adriana Méndez-Flores Ayerim Hérnandez-Almanza +3 位作者 AidéSáenz-Galindo Jesús Morlett-Chávez Cristóbal N Aguilar Juan Ascacio-Valdés 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2018年第12期676-681,共6页
Objective:To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety)husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometr... Objective:To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety)husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity.Methods:Rambutan husk extracts were obtained by ultrasound-assisted extraction,mass/volume ratio,water/ethanol percentage and extraction time were evaluated.Once the best extraction condition of polyphenolic compounds was defined,a polyphenolic fraction was recovered using Ambetlite XAD-16.The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents.Recovered compounds were identified by FTIR(ATR)spectroscopy and HPLC/ESI/MS.The antioxidant activity was carried out by ABTS,DPPH and lipid oxidation inhibition in vitro methods.Results:In Mexican variety rambutan husk,the total polyphenolic content was 487.67 mg/g,after ultrasound-assisted extraction.According to the HPLC/ESI/MS analysis 12 antioxidant polyphenolic compounds were identified,mostly ellagitannins such as geraniin,corilagin and ellagic acid.The antioxidant activity determined by ABTS,DPPH and lipid oxidation inhibition methods was demonstrated.The main functional groups of the identified compounds were determined by FTIR analysis.Conclusions:It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds.Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity,these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms. 展开更多
关键词 MEXICAN VARIETY RAMBUTAN ULTRA-SOUND assisted extraction ANTIOXIDANT polyphenolic COMPOUNDS HPLC/ESI/MS
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Effects of Ultrasound-Assisted Alkaline Extraction on the Structural and Emulsifying Properties of Chickpea Protein Isolate
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作者 ZHANG Yixue YANG Qing +4 位作者 CHENG Teng ZHENG Ruihan MA Wuchao HE Xiangli LI Ke 《食品科学》 北大核心 2025年第19期236-247,共12页
This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of ... This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of chickpea protein isolate(CPI).Compared with the non-ultrasound group,ultrasound treatment at 400 W resulted in the largest increase in CPI yield,and both the particle size and turbidity decreased with increasing ultrasound power from 0 to 400 W.The scanning electron microscope results showed a uniform structural distribution of CPI.Moreover,itsα-helix content increased,β-sheet content decreased,and total sulfhydryl group content and endogenous fluorescence intensity rose,illustrating that UAE changed the secondary and tertiary structure of CPI.At 400 W,the solubility of the emulsion increased to 63.18%,and the best emulsifying properties were obtained;the emulsifying activity index(EAI)and emulsifying stability index(ESI)increased by 85.42%and 46.78%,respectively.Furthermore,the emulsion droplets formed were smaller and more uniform.In conclusion,proper UAE power conditions increased the extraction yield and protein content of CPI,and effectively improved its structure and emulsifying characteristics. 展开更多
关键词 CHICKPEA ULTRASOUND extraction yield protein structure functional properties
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Ultrasound-assisted extraction of bound phenolic compounds from the residue of Apocynum venetum tea and their antioxidant activities 被引量:5
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作者 Shengwei Sun Yiwen Zhao +10 位作者 Luyao Wang Yuzhi Tan Yaning Shi Rita-Cindy Aye-Ayire Sedjoah Yuting Shao Longxiang Li Mengxi Wang Jiashuai Wan Xia Fan Rong Guo Zhihong Xin 《Food Bioscience》 SCIE 2022年第3期502-511,共10页
Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free ... Bound phenolic compounds from the residue of Apocynum venetum(A.venetum)tea were released by alkaline digestion with sonication,followed by extraction using ethyl acetate(EtOAc).The fragment ions of compounds in free and bound forms were identified by liquid chromatography electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)in both positive and negative modes.Further investigation of chemical constituents in the EtOAc extract led to the isolation of eleven individual compounds,and their chemical structures were identified as(−)-epicatechin(1),(−)-loliolide(2),(−)-syringaresinol-4-O-β-D-glucopyranoside(3),alloside of benzyl alcohol(4),3-[(6-O-hexopyranosylhexopyranosyl)oxy]-2-(palmitoyloxy)propyl(9Z,12Z,15Z)-9,12,15-octadecatrienoate(5),apocynoside I(6),quercetin-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucopyranoside(8),[1-acetyloxy-3-[3,4,5-trihydroxy-6-[[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxymethyl]oxan-2-yl]oxypropan-2-yl]hexadecanoate(9),1-stearoyl-2-palmitoyl-sn-glycerol(10),and 3-hexene-l-O-β-D-glucoside(11)using a series of spectroscopic methods.Compounds 2–5 and 9–11 were isolated for the first time from A.venetum,while antioxidant experiments showed that compounds 1,7,and 8 displayed strong DPPH and ABTS+radical scavenging activities.This study represents the first investigation of bound phenolic compounds with potential health benefits in the residue of A.venetum tea. 展开更多
关键词 Apocynum venetum.L tea residue ultrasound-assisted extraction Bound phenolic compounds Structural characterization Antioxidant activity
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Evaluating the effectiveness of ultrasound-assisted wound debridement in managing diabetic foot ulcers:A systematic review and meta-analysis 被引量:2
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作者 Rui Yang Geng Chen +5 位作者 Qing-Yun Pan Yao Yao Yan-Fen Li Hai-Ting Chen Chang-Jiang Lei Xia Liang 《World Journal of Diabetes》 2025年第2期246-256,共11页
BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therape... BACKGROUND Diabetic foot ulcers(DFUs)present a significant clinical challenge due to their high prevalence and profound impact on morbidity.Ultrasound-assisted wound debridement(UAWD)has emerged as a potential therapeutic modality to improve healing outcomes in DFU management.AIM To evaluate the efficacy of UAWD in treating DFUs on wound closure rates,treatment duration,and quality of life outcomes.METHODS This systematic review and meta-analysis followed PRISMA guidelines,systematically searching PubMed,Embase,Web of Science,and the Cochrane Library with no date restrictions.Randomized controlled trials(RCTs)that evaluated the efficacy of UAWD in DFU treatment were included.Data were independently extracted by two reviewers,with discrepancies resolved through consensus or third-party consultation.The risk of bias was assessed using the Cochrane tool.χ2 and I2 statistics assessed heterogeneity,informing the use of fixed or random-effects models for meta-analysis,supplemented by sensitivity analysis and publication bias assessment through funnel plots and Egger's test.RESULTS From 1255 articles,seven RCTs met the inclusion criteria.The studies demonstrated that UAWD significantly reduced DFU healing time(standardized mean difference=-0.78,95%CI:-0.97 to-0.60,P<0.001)and increased healing rates(odds ratio=9.96,95%CI:5.99 to 16.56,P<0.001)compared to standard care.Sensitivity analysis confirmed the stability of these results,and no significant publication bias was detected.CONCLUSION UAWD is a promising adjunctive treatment for DFUs,significantly reducing healing times and increasing healing rates.These findings advocate for the integration of UAWD into standard DFU care protocols. 展开更多
关键词 Diabetic foot ulcers ultrasound-assisted wound debridement Healing time Healing rates META-ANALYSIS
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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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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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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts
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作者 Xiao-Long Zhou Wei-Jin Jiang +2 位作者 Ji Yu Mao-Jun Yao Yun-Tong Li 《Traditional Medicine Research》 2025年第1期73-81,共9页
Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigat... Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties. 展开更多
关键词 vine tea DIHYDROMYRICETIN ultrasonic-assisted extraction volatile aroma components
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Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction
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作者 Shi Li Didi Sun 《Computers, Materials & Continua》 SCIE EI 2025年第1期1069-1086,共18页
With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions... With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant importance.Emotion-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying reasons.This comprehension is crucial for making informed strategic decisions in various business and societal contexts.However,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause extraction.To address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment mechanisms.The model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause pairs.Second,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among tasks.The proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 score.Experimental results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its effectiveness.This research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-cause pair extraction.However,the study’s limitation lies in the data sources,potentially restricting the generalizability of the findings. 展开更多
关键词 Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms
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Optimization of lithium extraction solar pond in Zabuye Salt Lake: Theoretical calculation combined with field experiments 被引量:1
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作者 Tao Ding Zhen Nie +6 位作者 Qian Wu Jiang-jiang Yu Ling-zhong Bu Yun-sheng Wang En-yuan Xing Mian-ping Zheng Yu-bin Li 《China Geology》 2025年第1期26-38,共13页
This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducte... This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducted experiments to investigate the influence of four factors related to solar pond structure on the crystallization of Li_(2)CO_(3) and their pairwise interactions.Computational Fluid Dynamics(CFD)simulations of the flow field within the solar pond were performed using COMSOL Multiphysics software to compare temperature distributions before and after optimization.The results indicate that the optimal structure for lithium extraction from the Zabuye Salt Lake solar ponds includes UCZ(Upper Convective Zone)thickness of 53.63 cm,an LCZ(Lower Convective Zone)direct heating temperature of 57.39℃,a CO32−concentration of 32.21 g/L,and an added soda ash concentration of 6.52 g/L.Following this optimized pathway,the Li_(2)CO_(3) precipitation increased by 7.34% compared to the initial solar pond process,with a 33.33% improvement in lithium carbonate crystallization rate.This study demonstrates the feasibility of optimizing lithium extraction solar pond structures,offering a new approach for constructing such ponds in salt lakes.It provides valuable guidance for the efficient extraction of lithium resources from carbonate-type salt lake brines. 展开更多
关键词 Salt lake Solar pond Lithium extraction Crystallization rate Box-Behnken Computational fluid dynamics Response surface Zabuye salt lake Mineral exploration engineering
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Physical Determination and Extraction of Annona muricata Seed Oil
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作者 Chioma Don-Lawson Reminus Okah Adele Ruth Chituru 《American Journal of Analytical Chemistry》 2025年第2期15-22,共8页
The physical examination of the fruit of soursop fruit (Annona muricata) selected from different parent trees was investigated. Three-stage modified Soxhlet method was used which includes a percolator (boiler and refl... The physical examination of the fruit of soursop fruit (Annona muricata) selected from different parent trees was investigated. Three-stage modified Soxhlet method was used which includes a percolator (boiler and reflux) which circulates the solvent, a thimble (usually made of thick filter paper) which retains the seed to be extracted, and a siphon mechanism, which periodically empties the condensed solvent from the thimble back into the percolator. The extraction of oil from the seed and the percentage yield was examined. The oil samples were characterized for physico-chemical properties. The maximum values of physical parameters found were fruit weight 3.7 ± 7.09, fruit length 12.2 ± 28.3 cm, with 15.2 ± 20.81 cm and 0.12 ± 18.91 g for pulp weight. The percentage oil yield of 48.5% was obtained due to the environmental factors such as the soil type, planting season and optimal temperature of the region of seed cultivation. The result of chemical properties showed maximum acid value 0.46 mg KOH, FFA of 0.33 mg, saponification of 189.4 mg KOH mg and peroxide value of 4.33 mg/g. The oil physical properties as discovered have a melting point of 32˚C, smoke point of 198˚C and flash point of 280˚C. The results obtained in this study further reveal the potential of oil from seed of soursop as a substitute for conventional vegetable oil due to its high flash point which is an indication of its low flammability and can be used as a good source of food, industrially can be used as an anti-microbial agent and for pest control. 展开更多
关键词 Soursop extraction Annona muricata Melting Point
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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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Optimization of Ultrasonic-Assisted Extraction Process for Anthocyanins from Lycium ruthenicum Murray
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作者 Yanjuan LUO Xiaojun WANG Guojun LI 《Asian Agricultural Research》 2025年第8期31-37,共7页
[Objectives]To investigate the optimal extraction conditions for anthocyanins from defatted Lycium ruthenicum Murray using ultrasonic-assisted solvent extraction.[Methods]Anthocyanins were extracted from wild L.ruthen... [Objectives]To investigate the optimal extraction conditions for anthocyanins from defatted Lycium ruthenicum Murray using ultrasonic-assisted solvent extraction.[Methods]Anthocyanins were extracted from wild L.ruthenicum in Qinghai Province using ultrasonic-assisted ethanol extraction.Through single-factor and orthogonal experiments,the optimal extraction conditions were determined as follows:temperature 50℃,solid-liquid ratio 1:15(g/mL),ethanol concentration 60%(v/v),and ultrasonic extraction time 25 min.Under these conditions,the anthocyanin content of L.ruthenicum was quantified by UV-Vis spectrophotometry at 280 nm.[Results]The extraction yield of anthocyanins from wild Qinghai L.ruthenicum was 17.0 mg/g,which is superior to the yield of 10.0 mg/g obtained by water solvent extraction,representing a 0.7%increase in extraction rate.The anthocyanin content in L.ruthenicum from different regions was determined,revealing that samples from the Chaidamu area in Qinghai had the highest content(17.3 mg/g),while samples from the Gansu area had the lowest(12.0 mg/g).[Conclusions]Ultrasonic-assisted ethanol extraction technology offers advantages including rapid operation,low energy consumption,high extraction yield,simple detection,and safety. 展开更多
关键词 LYCIUM ruthenicum Murray Anthocyanins ULTRASONIC-ASSISTED SOLVENT extraction extraction YIELD
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Corrosion resistance of a calcium carbonate coating prepared by ultrasound-assisted chemical conversion in calcium disodium edetate solution
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作者 Ye Wang Zhipeng You +5 位作者 Sanlve Pei Kai Ma Chaoneng Dai Danqian Wang Jingfeng Wang Fusheng Pan 《Journal of Magnesium and Alloys》 2025年第5期1994-2008,共15页
A CaCO_(3)coating with good anticorrosion and adhesion performance was fabricated via ultrasound-assisted chemical conversion on AZ41 magnesium alloy,with a water-bath treated coating as a control.The coating formed o... A CaCO_(3)coating with good anticorrosion and adhesion performance was fabricated via ultrasound-assisted chemical conversion on AZ41 magnesium alloy,with a water-bath treated coating as a control.The coating formed on AZ41 mainly consists of an outer CaCO_(3)layer and an inner(Ca,Mg)CO_(3)layer.Surface characterizations were carried out to obtain the morphology and the chemical composition,mechanical tests were also adopted to assess the hardness and the adhesion of the coating prepared.Afterwards,the long-term corrosion resistance was investigated via electrochemical methods in the chloride-containing Portland cement system.Results show that the ultrasound-assisted coating exhibits higher mechanical properties.In addition,the corrosion resistance of the ultrasound-assisted coating is also higher than that of the bare AZ41 alloy and the water-bath treated coating.This could be due to the formation of a much more compact CaCO_(3)coating on AZ41 Mg alloy,which is mainly benefit from the assistance of the ultrasound.Ultrasound accelerates the nucleation of CaCO_(3)crystals and assists the removal of hydrogen bubbles.Additionally,corrosion mechanism was suggested and discussed for the CaCO_(3)coating. 展开更多
关键词 Magnesium alloy Concrete formwork Calcium carbonate ultrasound-assisted chemical conversion Corrosion protection
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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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