期刊文献+
共找到183,219篇文章
< 1 2 250 >
每页显示 20 50 100
Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts
1
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
暂未订购
Optimization of Ultrasonic-Assisted Extraction Process for Anthocyanins from Lycium ruthenicum Murray
2
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
暂未订购
Optimization of Ultrasonic-Assisted Extraction Process of Polysaccharides from American Ginseng and Evaluation of Its Immunostimulating Activity 被引量:7
3
作者 YANG Xiu-shi WANG Li-jun +2 位作者 DONG Chuan Edmund Man King Lui REN Gui-xing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2807-2815,共9页
Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrason... Ultrasonic-assisted extraction (UAE) of American ginseng polysaccharides (AGP) was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography (GC) analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides. 展开更多
关键词 ultrasonic-assisted extraction POLYSACCHARIDES American ginseng response surface methodology immunostimulating activity
在线阅读 下载PDF
Optimization of Response Surface of Ultrasonic-assisted Extraction of Rizhao Black Tea 被引量:1
4
作者 TANG Yu-huan LIANG Qing +2 位作者 ZOU Jia-jia DING Xin DING Li-xiao 《Chinese Food Science》 2012年第3期35-38,共4页
[ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of t... [ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of tea polyphenols ultrasonic-assisted extraction process optimi- zation was applied. The regression optimization model of the ethanol volume fraction, ultrasonic time, and ultrasonic temperature, ethyl acetate extract stalling time and tea polyphenols was established. [ Result] The influence of four factors on the black tea polyphenol solvents affecting size was as follows: ultrasonic time 〉 ethanol volume fraction 〉 stalling extraction time 〉 ultrasound temperature. The best extraction process was ultrasonic time 80 min, volume fraction of 88.99% ethanol, extraction time 89.97 min, ultrasonic temperature of 80℃. At the optimized technical parameters, the black tea phenolic extraction yield can be as high as 73.50%. [ Conclusion] The study provided theoretical basis for the development of tea leaves and black tea. 展开更多
关键词 Rizhao black tea ultrasonic-assisted extraction extraction yield Response surface China
在线阅读 下载PDF
Mathematical modeling for of arctigenin from acidultrasonic-assisted extractionhydrolyzed FructusArctii
5
作者 Dai Lin Zhang Yong +2 位作者 Hu Chi Qian Hongliang Wang Zhixiang 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期362-369,共8页
A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid pr... A mathematical model based on Fick's first lawwas established to describe the process of ultrasonic-assisted extraction of arctigenin from acid hydrolyzed FructusArctii.Acid hydrolization with hydrochloric acid promotes the conversion of arctiin to arctigenin in the arctiin-rich active pharmaceutical ingredient, and the hydrolyzed products were further examined to investigate the process setup. By considering the mechanism of the extraction process and experimental data, the effects of parameters including solven to solid ratio, particle size of hydrolyzed samples, ethano volume fraction, ultrasound power, extraction temperature and extraction time on concentration of arctigenin were analyzed in detail. The model was suitable for simulating the process of ultrasonic-assisted extraction of arctigenin. The simulation results of the model agree well with experimental data with the deviation below13%, indicating that the mathematical mode can provide valuable guidance for the extraction of arctigenin from acid hydrolyzed FructusArctii. 展开更多
关键词 FructusArctii acid hydrolysis ultrasonic-assisted extraction ARCTIGENIN mathematical model
在线阅读 下载PDF
Optimization of Ultrasonic-assisted Extraction Process for Polysaccharide from Lactarius deliciosus by Response Surface Methodology and Its Antioxidant Activity
6
作者 Bei LIU Ting DING +4 位作者 Yufeng ZHENG Fang WU Mi TIAN Qian WANG Ting HU 《Agricultural Biotechnology》 2024年第6期46-51,共6页
[Objectives]Polysaccharide was extracted from Lactarius deliciosus by ultrasonic-assisted method to improve polysaccharide yield.[Methods]Five variables including extraction temperature,extraction time,ultrasonic powe... [Objectives]Polysaccharide was extracted from Lactarius deliciosus by ultrasonic-assisted method to improve polysaccharide yield.[Methods]Five variables including extraction temperature,extraction time,ultrasonic power,ultrasonic time and material-to-liquid ratio were selected for single factor experiments.The extraction process of L.deliciosus polysaccharide was optimized by response surface analysis,and its antioxidant activity was evaluated by measuring its total reduction ability and DPPH free radical scavenging capacity.[Results]The optimal extraction conditions were determined as follows:material-to-liquid ratio 1:35 g:ml,ultrasonic power 462 W,ultrasonic time 10 min,extraction time 110 min and extraction temperature 90℃.Under these conditions,the extraction rate of polysaccharide was(10.83±0.03)%.The antioxidant test results showed that when the mass concentration of L.deliciosus polysaccharide was 0.5 mg/ml,its absorbance and DPPH free radical scavenging rate reached their maximum values,which were 3.274%and 41.27%,respectively.The L.deliciosus polysaccharide had good antioxidant properties.[Conclusions]This study provides a theoretical basis for further development and utilization of L.deliciosus polysaccharide in the future. 展开更多
关键词 Lactarius deliciosus POLYSACCHARIDE ultrasonic-assisted extraction Response surface analysis Antioxidant activity
在线阅读 下载PDF
Antioxidant and hepatoprotective effects of Ajuga nipponensis extract by ultrasonic-assisted extraction 被引量:4
7
作者 Chang-Wei Hsieh Wen-Ching Ko +3 位作者 Wai-Jane Ho Chao-Kai Chang Guo-Jhou Chen Jen-Chieh Tsai 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第5期409-414,共6页
Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction paramet... Objective: To investigate suitable condition for extraction of the active components from Ajuga nipponensis(A. nipponensis). Methods: Orthogonal experimental design was used to determine the optimal extraction parameters for ecdysterones and flavonoids. Finally, the hepatoprotective abilities of A. nipponensis extracts were evaluated by CCl_4-induced animal models. Results:Maximum yields of flavonoids(7.87±0.10) mg/g and ecdysterones(0.73±0.02) mg/g could be obtained when the extraction time was 50 min, the extraction temperature was 60 ℃, and the ratio of sample to 70%(v/v) ethanol was 1:20(w/w). The antioxidant property of A. nipponensis was correlated to the concentration of its extracts. At 5 mg/m L, A. nipponensisextract scavenged 84.8% of DPPH radical and had absorbance values of 2.43±0.04 reducing power. Upon CCl_4-induced liver injury, glutamic oxaloacetic transaminase and glutamic pyruvic transaminase decreased significantly after the mice were treated with A. nipponensis. Histological researches also explained that A. nipponensis reduced the extent of liver lesions induced by CCl_4. Conclusions: A. nipponensis exhibited potent antioxidant activity in chemical experimental models and hepatoprotective effect against CCl_4-induced liver damage. 展开更多
关键词 Ajuga nipponensis ultrasonic-assisted extraction ORTHOGONAL test ANTIOXIDANT HEPATOPROTECTION
暂未订购
An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L. 被引量:16
8
作者 Jingyao Tian Siddique Muhammad +5 位作者 Ai Chen Peng Chen Jinghong Wang Chengwu Yang Hui Yuan Zhensheng Wang 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第5期1735-1741,共7页
In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations an... In this paper,the ultrasonic-assisted extraction process of flavonoid compounds from leaves of Amorpha fruticosa is optimized.In single factor experiments,solid/liquid ratios,ultrasonic power,ethanol concentrations and extraction cycles were experimental factors.Box–Behnken central composite design and RSM analyzed the effects of the four factors on the yield of total flavonoids.The optimal extraction parameters were solid/liquid ratio 1:50 g/mL,ultrasonic power 316 W,ethanol concentration 50%,4 extraction cycles.In the optimized condition,the estimated value of the regression model was 66.6456 mg/g while the measured value was 66.4329 mg/g. 展开更多
关键词 Amorpha fruticosa L. Flavonoid COMPOUNDS ULTRASONIC extraction Response surface METHODOLOGY
在线阅读 下载PDF
Evaluating the performances of accelerated-solvent extraction, microwave-assisted extraction, and ultrasonic-assisted extraction for determining PCBs, HCHs and DDTs in sediments 被引量:1
9
作者 张蓬 葛林科 +1 位作者 周传光 姚子伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1103-1112,共10页
Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments, i.e. accelerated solvent extraction (ASE), microwave assisted extraction (MAE) ... Three extraction techniques have been recently used for the quantitative extraction of semi-volatile organic pollutants in sediments, i.e. accelerated solvent extraction (ASE), microwave assisted extraction (MAE) and ultrasonic assisted extraction (UAE). However, their extraction efficiencies have rarely been quantitatively compared using rigorous mathematical methods. In this paper, one-way analysis of variance (ANOVA) was employed to evaluate the performance of ASE, MAE and UAE in the overall extraction of PCBs, DDTs and HCHs by analysis of their recoveries from the Standard Reference Material IAEA-417, a sediment sample certified by many international laboratories. Conclusions were drawn at a significance level of P〈 0.05. No significant differences were found among the mean values for method recoveries using ASE, MAE and UAE. The mean values for real recoveries using ASE and MAE were nearly identical, but the real recovery using UAE was much lower. The concentrations of all PCBs, DDTs and HCHs except for CB52 and o,p'-DDT using UAE were the lowest. Comparing the results obtained using ASE with MAE, the concentrations of CB28, CB52, CB138, ct-HCH, [3-HCH, p,p'-DDE and p,p'-DDD were nearly identical, while the concentrations of other compounds were significantly different. Based on the low recoveries, it was concluded that UAE is a relatively inefficient extraction method, while ASE and MAE are equivalent methods. Taking into consideration the relative standard deviation (RSD) values, solvent volume, extraction time, and purchasing costs of the apparatus, MAE was considered superior to ASE for extraction of PCBs, DDTs and HCHs. 展开更多
关键词 extraction technique sediment PCB HCH DDT
原文传递
Optimization of the Ultrasonic-assisted Extraction Process for Total Flavonoids in Primula sikkimensis Hook.by Response Surface Methodology 被引量:1
10
作者 Qing XIA Dandan TANG +1 位作者 Zhiqiang ZHANG Jianhui JIANG 《Medicinal Plant》 CAS 2021年第1期35-39,共5页
[Objectives]To optimize the ultrasonic-assisted extraction process for total flavonoids in Primula sikkimensis Hook.[Methods]The effects of ethanol volume fraction,extraction time,extraction temperature,ultrasonic tim... [Objectives]To optimize the ultrasonic-assisted extraction process for total flavonoids in Primula sikkimensis Hook.[Methods]The effects of ethanol volume fraction,extraction time,extraction temperature,ultrasonic time and solid-to-liquid ratio on the yield of total flavonoids were investigated by single factor method,and the extraction process for total flavonoids in P.sikkimensis was optimized by Box-Behnken experimental design.[Results]The optimal extraction process for total flavonoids in P.sikkimensis was ethanol volume fraction 45%,extraction time 29 min,extraction temperature 80℃,solid-to-liquid 1∶40(g/mL)and ultrasonic time 10 min.Under such conditions,the average yield of total flavonoids in P.sikkimensis was 3.09%.[Conclusions]The optimized extraction process is simple and feasible,and is expected to provide a reference for the extraction of total flavonoids in P.sikkimensis. 展开更多
关键词 Primula sikkimensis Hook. Total flavonoids Response surface methodology(RSM) extraction process
暂未订购
Optimization of Ultrasonic-assisted Extraction of Polysaccharide from Hibiscus syriacus L.
11
作者 Haibo DENG Bei NING +3 位作者 Shunfan ZHU Chenzhong JIN Yihong HU Xuejiao ZHANG 《Agricultural Biotechnology》 CAS 2018年第3期161-164,共4页
The ultrasonic-assisted extraction of polysaccharides from Hibiscus syriacus L. at 180 W low power was optimized by the single factor tests and orthogonal test. Extraction temperature,ultrasonic treatment time,extract... The ultrasonic-assisted extraction of polysaccharides from Hibiscus syriacus L. at 180 W low power was optimized by the single factor tests and orthogonal test. Extraction temperature,ultrasonic treatment time,extraction times,and material-to-liquid ratio were considered as independent variables. The results suggested that the best extraction condition were determined as the extraction temperature at 80 ℃,the ultrasonic treatment time of 40 min,the material-to-liquid ratio at1∶ 20( g/ml),and the extraction times of 3. Under the optimal conditions,the extraction rate of polysaccharides from Hibiscus syriacus was 3. 114%. 展开更多
关键词 Hibiscus syriacus L. POLYSACCHARIDE Ultrasound-assisted extraction
在线阅读 下载PDF
Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization
12
作者 L.Antony Catherine Flora Kirubanandan Shanmugam Renganathan Sahadevan 《Proceedings of Anticancer Research》 2024年第5期89-104,共16页
Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the caroten... Macroalgae serve as a potential feedstock for fucoxanthin extraction.Fucoxanthin,a bioactive pigment found in the chloroplasts of marine algae,exhibits significant pharmacological properties.As a member of the carotenoid family,fucoxanthin plays a crucial role in both the food and pharmaceutical industries.This research explores the effects of ultrasonics on the extraction of fucoxanthin from the marine macroalga Padina australis.In addition,various extraction techniques and the influence of solvents on the efficient separation of fucoxanthin from algae have been studied and compared.Using methanol,chloroform,and a combination of methanol and chloroform(1:1,v/v),conventional fucoxanthin extraction from Padina australis yielded 8.12 mg of fucoxanthin per gram of biomass.However,the ultrasonic-assisted extraction resulted in a significantly higher yield of 16.9 mg of fucoxanthin per gram of biomass,demonstrating that the use of ultrasonics enhances the extraction rate compared to conventional methods.Therefore,the efficient separation of fucoxanthin from Padina australis is highly dependent on ultrasonic-assisted extraction.The process conditions for the extraction were optimized to maximize the yield of fucoxanthin from seaweeds.The following parameters were selected for optimization studies:moisture content,particle size,mixing speed,extraction temperature,extraction duration,and solid-to-solvent ratio.The extracted fucoxanthin exhibited various biological activities,including antimicrobial and antioxidant properties,and its structure was elucidated through FTIR and NMR spectroscopy.Additionally,thin-layer chromatography of the crude algae extracts confirmed the presence of fucoxanthin in the marine algae.Given these findings,the optimized extraction process holds the potential for scaling up to large-scale fucoxanthin production.Fucoxanthin,as a potent pharmacological agent,offers promising applications in the treatment of various ailments. 展开更多
关键词 Marine algae FUCOXANTHIN ULTRASONICS extraction OPTIMIZATION TLC DPPH Antimicrobial antioxidant activities
在线阅读 下载PDF
Analysis of volatile components in saffron from Tibet and Henan by ultrasonic-assisted solvent extraction and GC-MS 被引量:1
13
作者 贾凌晗 刘一 李玉珍 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第4期404-409,共6页
To determine the chemical constituents of volatile components in saffron from the Tibet Autonomous Region and the Henan Province of China and to compare the chemical composition difference in the saffron,the total vol... To determine the chemical constituents of volatile components in saffron from the Tibet Autonomous Region and the Henan Province of China and to compare the chemical composition difference in the saffron,the total volatile components were extracted by ultrasonic-assisted solvent extraction(USE),using five different solvents:diethyl ether,ethanol,ethyl acetate, dichloromethane and acetone,analyzed using gas chromatography-mass spectrometry(GC-MS)and compared to the standard MS data,and their relative contents were calculated by area normalization.The results showed both that USE was an efficient and rapid method for the extraction of the volatile components from saffron and that the components extracted from the same sample using different solvents were different.Comparison of the experimental results of saffron from the Tibet Autonomous Region and the Henan Province of China showed that their volatile components were different in their chemical composition and in their relative percentages.USE/GC-MS is a simple,rapid,and effective method for the analysis of volatile oil components in saffron. 展开更多
关键词 SAFFRON Volatile components ultrasonic-assisted solvent extraction GC-MS
原文传递
Artificial intelligence-enabled high-precision colony extraction and isolation system
14
作者 ZHAO Xu-feng JIA Zhi-qiang +5 位作者 CHEN Wei-xue HU Peng-tao SU Xin-ran LI Jun-lin GE Ming-feng DONG Wen-fei 《中国光学(中英文)》 北大核心 2026年第1期190-204,共15页
Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and... Standard bacterial suspensions play a crucial role in microbiological diagnosis.Traditional prepar-ation methods,which rely heavily on manual operations,face challenges such as poor reproducibility,low ef-ficiency,and biosafety concerns.In this study,we propose a high-precision automated colony extraction and separation system that combines large-field imaging and artificial intelligence(AI)to facilitate intelligent screening and localization of colonies.Firstly,a large-field imaging system was developed to capture high-resolution images of 90 mm Petri dishes,achieving a physical resolution of 13.2μm and an imaging speed of 13 frames per second.Subsequently,AI technology was employed for the automatic recognition and localiza-tion of colonies,enabling the selection of target colonies with diameters ranging from 1.9 to 2.3 mm.Next,a three-axis motion control platform was designed,accompanied by a path planning algorithm for the efficient extraction of colonies.An electronic pipette was employed for accurate colony collection.Additionally,a bacterial suspension concentration measurement module was developed,incorporating a 650 nm laser diode as the light source,achieving a measurement accuracy of 0.01 McFarland concentration(MCF).Finally,the system’s performance was validated through the preparation of an Esckerichia coli(E.coli)suspension.After 17 hours of cultivation,E.coli was extracted four times,achieving the target concentration set by the system.This work is expected to enable rapid and accurate microbial sample preparation,significantly reducing de-tection cycles and alleviating the workload of healthcare personnel. 展开更多
关键词 artificial intelligence colony extraction and isolation large-field imaging AUTOMATION
暂未订购
Low-temperature bonding of W90 tungsten heavy alloy using Sn−2Al filler metal by ultrasonic-assisted coating technology
15
作者 Xiao-guo SONG Xu-dong ZHANG +3 位作者 Wei FU Xiao-yu TIAN Guang-dong WU Sheng-peng HU 《Transactions of Nonferrous Metals Society of China》 2026年第1期259-272,共14页
The Sn−2Al filler metal was utilized to bond W90 tungsten heavy alloys by the ultrasonic-assisted coating technology in atmospheric environment at 250℃.The effects of ultrasonic power and ultrasonic time on microstru... The Sn−2Al filler metal was utilized to bond W90 tungsten heavy alloys by the ultrasonic-assisted coating technology in atmospheric environment at 250℃.The effects of ultrasonic power and ultrasonic time on microstructure and interfacial strength of Sn−2Al/W90 interface were investigated.The ultrasound improved the wettability of Sn−2Al filler metal on W90 surface.As the ultrasonic power increased and ultrasonic time increased,the size of Al phase in seam decreased.The maximum value of Sn−2Al/W90 interfacial strength reached 30.1 MPa.Based on the acoustic pressure simulation and bubble dynamics,the intensity of cavitation effect was proportional to ultrasonic power.The generated high temperature and high pressure by cavitation effect reached 83799.6 K and 1.26×10^(14) Pa,respectively. 展开更多
关键词 W−Ni−Fe alloy Sn−Al filler metal ultrasonic-assisted coating technology acoustic pressure CAVITATION bubble dynamics
在线阅读 下载PDF
Flexible High-Aspect-Ratio COF Nanofibers:Defect-Engineered Synthesis,Superelastic Aerogels,and Uranium Extraction Applications
16
作者 Binbin Fan Jianyong Yu +2 位作者 Xueli Wang Yang Si Peixin Tang 《Nano-Micro Letters》 2026年第5期15-30,共16页
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis... The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness. 展开更多
关键词 Defect cleavage COF nanofibers Flexibility AEROGELS Uranium extraction
在线阅读 下载PDF
Systematic explorations for the effect of nitric acid on radiolysis of TODGA/kerosene:extraction behavior and DFT investigations for the complexation of lanthanides
17
作者 Jia-Wei Zheng Shu-Yi Yang +2 位作者 Hao Wu Yan Wu Yue-Zhou Wei 《Nuclear Science and Techniques》 2026年第5期264-277,共14页
N,N,N',N'-tetraoctyl diglycolamide(TODGA)is a potential extractant for the co-extraction of lanthanides and actinides in high-level liquid waste.In this study,the radiolysis and extraction properties of TODGA ... N,N,N',N'-tetraoctyl diglycolamide(TODGA)is a potential extractant for the co-extraction of lanthanides and actinides in high-level liquid waste.In this study,the radiolysis and extraction properties of TODGA in kerosene solvents contacted with the aqueous phase of varying HNO_(3) concentrations were systematically investigated,and the complexation mechanism was analyzed in conjunction with density functional theory(DFT)calculations.After γ-irradiation,the variation of TODGA concentration was detected,and the variation trends in the relative content of radiolysis products(RPs)with sample type and absorbed dose were demonstrated.Results indicated that the breaking of the amide bond,ether bond,and C_(amide)-C_(ether)bond was the primary radiolysis routes.The aqueous-phase precipitate was studied as a potential new mode of TODGA radiolysis in ultrapure water aqueous phase.Moreover,TODGA/kerosene exhibited excellent extraction capabilities for lanthanides even after absorbing 100 kGy,and HNO_(3) can maintain a portion of TODGA's extraction capacity.The DFT method was applied to calculate and evaluate the complexing ability of TODGA and some of its RPs toward lanthanides.The results revealed that the complexing ability of TODGA for Ce(Ⅲ),Eu(Ⅲ),and Dy(Ⅲ)was enhanced successively,and the complexing ability of the RPs with intact oxygen-containing structures could not be neglected. 展开更多
关键词 TODGA KEROSENE Systematic research Radiolysis product extraction DFT calculation
在线阅读 下载PDF
Straightforward and versatile construction of phenanthroline-derived diamide ligands for f-block element extraction
18
作者 Dong Fang Xiaofan Yang +1 位作者 Fengxin Gao Chengliang Xiao 《Chinese Chemical Letters》 2026年第1期602-605,共4页
As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive stu... As an important class of phenanthroline derivatives containing soft N and hard O donor atoms,the laborious syntheses of unsymmetrical 1,10-phenanthroline-derived diamide ligands(DAPhen) have hindered its extensive study.In this work,we first report a convenient synthetic method for the construction of DAPhen using Friedländer reaction by two facile steps(vs.previous 12 steps).A variety of DAPhen ligands are readily available,especially unsymmetrical ones,which give us a platform to systematically study the substituent effect on f-block elements extraction performance.The performance of unsymmetrical extractants is experimentally confirmed to falls between that of their corresponding symmetrical extractants by extracting UO_(2)^(2+) as the representative f-block element.This work provides a direct and versatile method to synthesize symmetrical and unsymmetrical DAPhen,which paves way for the investigations on their coordination properties with metal ions and other applications. 展开更多
关键词 Phenanthroline diamide ligand Friedlander reaction UNSYMMETRICAL SYMMETRICAL Solvent extraction
原文传递
T-Pointer:A Chinese Text Semantic Extraction Model for Semantic Communication
19
作者 Qian Liping Qian Jiang +3 位作者 Wu Wanwan Huang Liang Wu Yuan Yang Xiaoniu 《China Communications》 2026年第2期298-311,共14页
Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future... Text semantic extraction has been envisioned as a promising solution to improve the data transmission efficiency with the limited radio resources for the autonomous interactions among machines and things in the future sixth-generation(6G)wireless networks.In this paper,we propose a Chinese text semantic extraction model,namely T-Pointer,to improve the quality of semantic extraction by integrating the Transformer with the pointer-generator network.The proposed T-Pointer model consists of a semantic encoder and a semantic decoder.In the encoding stage,we use the multi-head attention mechanism of the Transformer to extract semantic features from the input Chinese text.In the decoding stage,we first use the Transformer to extract multi-level global text features.Then,we introduce the pointer-generator network model to directly copy the keyword information from the source text.The simulation results demonstrate that the T-Pointer model can improve the bilingual evaluation understudy(BLEU)and recalloriented understudy for gisting evaluation(ROUGE)by 14.69%and 14.87%on average in comparison with the state-of-the-art models,respectively.Also,we implement the T-Pointer model on a semantic communication system based on the universal software radio peripheral(USRP)platform.The result shows that the packet delay of semantic transmission can be reduced by 52.05%on average,compared to traditional information transmission. 展开更多
关键词 attention mechanism pointer-generator network semantic communication semantic extraction TRANSFORMER
在线阅读 下载PDF
Highly enhanced scandium extraction and back-extraction efficiencies using a new C272–iso-octanol synergistic system
20
作者 Ziyun Zhang Yanlin Zhang +5 位作者 Wenyu Shen Dapeng Guo Hongbo Wang Duo Wang Fang Zhou Chao Yang 《Chinese Journal of Chemical Engineering》 2026年第1期198-207,共10页
This article presents a new synergistic extraction system composed of Cyanex 272(C272,bis(2,4,4-trimethylpentyl)phosphinic acid)and iso-octanol for Sc_(3+) separation.The proposed synergistic system possessed an Sc^(3... This article presents a new synergistic extraction system composed of Cyanex 272(C272,bis(2,4,4-trimethylpentyl)phosphinic acid)and iso-octanol for Sc_(3+) separation.The proposed synergistic system possessed an Sc^(3+) extraction efficiency of 93.5%and a back-extraction efficiency of 82.7%,with selectivity coefficients of β_(Sc/Fe)=459 and β_(Sc/Al)=4241,which are considerably higher as compared to the current extraction systems.The extraction mechanism was studied and interpreted.The enhanced extraction efficiency is attributed to the increased hydrophobicity of the ternary complex,whereas the back-extraction efficiency can be ascribed to the attenuated stability of the complex.C272 and C272–iso-octanol systems also possess considerable surface activity,which is beneficial for the phase separation in solvent extraction.Based on the solvent extraction results,a preliminary study was conducted on polymer inclusion membranes(PIMs)using the binary system for Sc^(3+) separation to avoid the formation of the third phase,achieving an optimal initial flux of PIM of 6.71×10^(−4)mol·m^(−2)·h^(−1).Our results provide valuable information on highly efficient Sc^(3+) separation,and the study on PIM extraction has shown a green alternative to solvent extraction. 展开更多
关键词 SCANDIUM Solvent extraction Polymer inclusion membrane C272 Iso-octanol
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部