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Study on Extraction of Oolong Tea Assisted by Ultrasonic Wave and 4C Technique and Its Application
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作者 Guofeng YU Cuishu LENG +9 位作者 Keli FANG Zhiguang LIU Jianhong SUN Zengyu Wang Xuegang LI Shuai Zhang Jian LIU Xulun WEI Qiulin LIU Shoujie NIE 《Agricultural Biotechnology》 2024年第3期24-27,共4页
[Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea ext... [Objectives]The extraction conditions of formula oolong tea were investigated by an orthogonal experiment.[Methods]The technical conditions were optimized by the 4C method,and the application of formula oolong tea extract in cigarettes was studied.[Results]①In the experimental range,the best sensory evaluation effect of formula oolong tea extract was obtained with extraction conditions of 70%ethanol as extraction solvent,extraction time h,extraction temperature 25℃,and ultrasonic frequency 80 kHz,and follow-up low-temperature concentration,low-temperature sedimentation and low-temperature centrifugation.②The effects of different centrifugal speeds on the quality of formula oolong tea extract were explored.The formula oolong tea extract obtained under the conditions of 3000 r/min and centrifugal time of 10 min showed the best evaluation effect with soft and delicate smoke,rich smoke fragrance,good comfort and refreshing mouthfeel.③The effective aroma components in the formula oolong tea extract were qualitatively analyzed by GC-MS.[Conclusions]This study provides high-quality raw materials and a theoretical basis for the research of independent flavor blending in cigarette industry enterprises. 展开更多
关键词 Combined application of ultrasonic wave and 4C technique Orthogonal experiment Formula extraction FLAVOR
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Ultrasonic-Assisted Extraction of Fucoxanthin from Marine Macroalga Padina australis:Optimization,Bioactivity,and Structural Characterization
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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
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Analysis of Ultrasonic Emulsification Surgery and Small Incision Cataract Extracapsular Extraction Surgery for Cataract Clinical Treatment Level Improvement
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作者 Chunyan Ji 《Journal of Clinical and Nursing Research》 2024年第2期196-200,共5页
Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected an... Objective:To analyze the efficacy of ultrasonic emulsification and small incision cataract extracapsular extraction in cataract patients.Methods:96 cataract patients admitted from May 2021 to May 2023 were selected and randomly grouped into group A(ultrasonic emulsification)and group B(small-incision extracapsular cataract extraction),with 48 cases each.Results:At 1 week,1-month,and 3 months post-operation,the visual acuity of group A was higher and the astigmatism value was lower than that of group B(P<0.05);at 12h,24h,and 48h post-operation,the intraocular pressure of group A was higher than that of group B(P<0.05);the thickness of macular area of group A was lower than that of group B at 1 week and 1-month post-operation(P<0.05).Conclusion:Ultrasonic emulsification in cataract patients was slightly better than small incision cataract extracapsular extraction in correcting astigmatism,improving visual acuity,and regulating macular thickness.However,due to the high energy of ultrasonic emulsification,the risk of complications such as high postoperative intraocular pressure was higher.Small-incision extracapsular cataract extraction has better application value in economically disadvantaged areas. 展开更多
关键词 CATARACT Cataract ultrasonic emulsification Small incision cataract extracapsular extraction Therapeutic efficacy
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Optimal Ultrasonic Extraction of Pachyman from Jiuzihe Poria cocos 被引量:7
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作者 刘丽 徐春 +2 位作者 李可 姜昆 吴鹏 《Agricultural Science & Technology》 CAS 2016年第12期2746-2750,2776,共6页
This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ul... This study was conducted to extract pachyman to the greatest degree with ultrasonic technology, and to determine the content of pachyman by the phe-nol-sulfuric acid method, so as to choose the optimal technique of ultrasonic extrac-tion of pachyman. Firstly, the ultrasonic power, extraction time and solid-to-liquid ra-tio were investigated by ultrasonic extraction method. Then, on this basis, a respon-sible surface experiment was designed, to select the optimal process conditions ac-cording to the index of pachyman yield. The optimized ultrasonic water extraction conditions were as fol ow: ultrasonic power of 100 W, extraction time of 30 min, and solid-to-liquid ratio at 1:40. The Oxford cup method was used to study the an-timicrobial activity of pachyman. lt was found that pachyman could significantly in-hibit Bacilus subtilis_and Staphylococcus aureus. 展开更多
关键词 Poria cocos Pachyman ultrasonic extraction Response surface An-timicrobial activity
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Optimal ultrasonic extraction condition and determination of polysaccharides in Tilia amurensis flowers 被引量:2
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作者 穆立蔷 刘立平 马大龙 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期77-80,I0003,共5页
Seven extracting temperatures (25, 35, 45, 55, 65, 75, 85℃) and extracting time (30, 40, 50, 60, 70, 80, 90 min) were designed for selecting the optimal extracting time and extracting temperature for ultrasonic e... Seven extracting temperatures (25, 35, 45, 55, 65, 75, 85℃) and extracting time (30, 40, 50, 60, 70, 80, 90 min) were designed for selecting the optimal extracting time and extracting temperature for ultrasonic extraction of T. amurensis flowers. Polysaccharides from T. amurensis flowers were isolated and determined by spectrophotometry. Results show that the optimal ultrasonic temperature was 75℃ and ex tracting time 52 min. The content of polysaccharides in T. amurensis flowers measured by anthrone--H2SO4 colorimetry under 580 nm, was 9.74% with 0.47% of relative standard deviation (RSD, n=3). This study demonstrated that ultrasonic extraction method was simple, and the color of the treated samples was stable in 4 h. The average recovery value for the polysaccharides measured was 99.48%±1.01%, with 0.112% of RSD (n=3). 展开更多
关键词 best extracting condition POLYSACCHARIDES Tilia amurensis flowers ultrasonic extraction
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Ultrasonic Assisted Extraction of Anthocyanins from Strawberry
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作者 孙建霞 翟熙 +3 位作者 张振华 邱瑞霞 欧仕益 白卫滨 《Agricultural Science & Technology》 CAS 2014年第8期1403-1406,1432,共5页
This study aimed to explore the main factors influencing the extraction of anthocyanins from strawberry, such as solid-liquid ratio, concentration of solvent, duration of ultrasonic treatment and ultrasonic power. Acc... This study aimed to explore the main factors influencing the extraction of anthocyanins from strawberry, such as solid-liquid ratio, concentration of solvent, duration of ultrasonic treatment and ultrasonic power. According to the results of sin-gle factor test, an orthogonal experiment was designed to determine the optimum extraction conditions. The effects of the four factors on anthocyanins extraction from strawberry were listed here in an decreasing order: ethanol concentration 〉 solid-liq-uid ratio〉duration of ultrasonic treatment〉ultrasonic power. And the optimal condi-tions of ultrasonic extraction of anthocyanins from strawberry were: ultrasonic treat-ment of 30 min, solid-liquid ratio of 1:15, ethanol concentration of 60% and ultra-sonic power of 300 W. Under such conditions, the content of extracted antho-cyanins was 33.247 mg/100g, which was 1.3 folds higher than that by extraction without ultrasonic treatment. 展开更多
关键词 ultrasonic extraction STRAWBERRY ANTHOCYANIN
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An experimental study exploring the influencing factors for ultrasonic-assisted extraction of flavonoid compounds from leaves of Amorpha fruticosa L. 被引量:15
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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
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Polyphenols extracted from Aronia melanocarpa by combined enzymatic and ultrasonication and their antioxidant potential and antimicrobial activity
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作者 Xinzhu Zhang Ming Song +1 位作者 Weizhuo Xu Wei Xu 《Journal of Polyphenols》 2023年第1期35-47,共13页
The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction condit... The extraction of polyphenols from Aronia melanocarpa was carried out using a combination of enzymatic and ultrasound.After single-factor and orthogonal design and experiment,the optimized polyphenol extraction conditions were 1%enzyme,1:40 material-to-liquid ratio,55℃,60 min ultrasonication,70%ethanol,and the final extraction amount was 88.634 mg/g,which displayed a 25.15%and 34.08%improvement compared with the single ultrasonication and enzymatic extraction methods,respectively.Significant antibacterial effects of polyphenols were shown against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.Further antioxidation effects were evaluated,and the superoxide anion radical scavenging rate,hydroxyl radical scavenging rate and DPPH free radical scavenging rate reached 45.2%,83.5%and 85.4%,respectively.This combined enzymatic and ultrasonic extraction method exhibited the advantages of high extraction rate,saving solvent consumption and extraction time,but also provided a new method for the development and utilization of natural antimicrobial and antioxidant health products. 展开更多
关键词 Aronia melanocarpa phenolic compounds enzymatic extraction ultrasonication antibacterial effect antioxidation effect
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Extraction of Organochlorine Pesticides in Sediments Using Soxhlet,Ultrasonic and Accelerated Solvent Extraction Techniques 被引量:9
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作者 LANGYinhai CAOZhengmei NIEXinhua 《Journal of Ocean University of China》 SCIE CAS 2005年第2期173-176,共4页
The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake ... The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented. 展开更多
关键词 organochlorine pesticides Taihu Lake sediments soxhlet extraction ultrasonic extraction accelerated solvent extraction
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The Optimization of Ultrasonic Extraction Technology of Total Flavonoids in Leaves of Mallotus apelta by Response Surface Analysis Methodology 被引量:9
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作者 Dengfeng ZOU Ruifen FAN +1 位作者 Xiao HUANG Aize XIE 《Medicinal Plant》 CAS 2018年第4期68-72,共5页
[Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assiste... [Objectives] Response surface analysis methodology was used to optimize the extraction technology of total flavonoids from Mallotus apelta leaves. [Methods] The total flavonoids were extracted using ultrasonic assisted ethanol extraction,and extraction rate of total flavonoids was taken as evaluation index. On the basis of single-factor experiment,Box-Behnken response surface methodology was employed for selecting the optimum extraction process. [Results]The optimum extraction conditions of total flavonoids were as follows: 75% of ethanol concentration,1∶ 25 of ratio of material to liquid,31 min of ultrasonic time. Under these conditions,the extraction rate of total flavonoids was 1. 115%.[Conclusions] The extraction process obtained by response surface methodology was stable,reasonable,accurate and reliable. It was a feasible method to extract the total flavonoids from M. apelta leaves. 展开更多
关键词 Mallotus apelta Total flavonoids ultrasonic extraction Response surface methodology
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Ultrasonic Extraction of Polysaccharides from Laminaria japonica and Their Antioxidative and Glycosidase Inhibitory Activities 被引量:6
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作者 WAN Peng YANG Xiaoman +4 位作者 CAI Bingna CHEN Hua SUN Huili CHEN Deke PAN Jianyu 《Journal of Ocean University of China》 SCIE CAS 2015年第4期651-662,共12页
In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Lami- naria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities ar... In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Lami- naria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design (BBD) combined with response surface methodology (RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80℃ and ratio of material to solvent at 1:50 (g mL-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield (5.75% + 0.3%) is close to the predicted result (5.67%) with no significant difference (P〉0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides (LJP) and two major ethanol precipitated fractions (LJP1 and LJP2) are in a concentration-dependent manner. LJP2 (30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase in- hibitory activity and moderate scavenging activity against hydroxyl radicals (66.09% ±2.19%, 3.0 mg mL-l). Also, the inhibitory activity against a-glucosidase (59.08% ± 3.79%, 5.0 mg mL-1) is close to that of acarbose (63.99% ± 3.27%, 5.0 mg mL-l). LJP 1 (30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals (99.80%q-0.00%, 3.0mg mL-1) and moderate a-glucosidase inhibitory activity (47.76%± 1.92%, 5.0 mgmL-1). LJP shows the most remarkable DPPH scav- enging activity (66.20%±0.11%, 5.0mgmL-1) but weakest a-glucosidase inhibitory activity (37.77%±1.30%, 5.0mgmL-1). How- ever, all these LJPs exert weak inhibitory effects against a-amylase. These results show that UET is an effective method for extract- ing bioactive polysaccharides from seaweed materials. LJP 1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of diabetes. This study provides scientific evidence and advances in the preparation technology and a hypoglycemic activities evaluation method for seaweed polysaccharides, especially glycosidase inhibition in com- bination with an antioxidative activity evaluation method. 展开更多
关键词 POLYSACCHARIDES Laminariajaponica ultrasonic extraction ANTIOXIDATIVE Α-GLUCOSIDASE a-amylase
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Rapid determination of volatile constituents in safflower from Xinjiang and Henan by ultrasonic-assisted solvent extraction and GC-MS 被引量:3
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作者 Ling-Han Jia Yi Liu Yu-Zhen Li 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第3期213-218,共6页
The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide s... The total volatile components were extracted from safflower by ultrasonic-assisted solvent extraction (USE) and their chemical constituents were analyzed by gas chromatographymass spectrometry (GC-MS) to provide scientific basis for the quality control of safflower. Five different solvents (diethyl ether, ethanol, ethyl acetate, dichloromethane and acetone) were used and compared in terms of number of volatile components extracted and the peak areas of these components in TIC. The results showed that USE could be used as an efficient and rapid method for extracting the volatile components from safflower. It also could be found that the number of components in the TIC of ethyl acetate extract was more than that in the TIC of other solvent ones. Meanwhile, the volatile components of safflower from Xinjiang Autonomous Region and Henan Province of China were different in chemical components and relative contents. It could be concluded that both the extraction solvents and geographical origin of safflower are responsible for these differences. The experimental results also indicated that USE/GC-MS is a simple, rapid and effective method to analyze the volatile oil components of safflower. 展开更多
关键词 SAFFLOWER ultrasonic solvent extraction Gas chromatographymass spectrometry (GC-MS)
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Study on Ultrasonic Extraction of Total Flavonoids from Angelica keiskei Koidzumi 被引量:4
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作者 Yaoming HU Donghai CHU 《Agricultural Biotechnology》 CAS 2016年第3期6-8,共3页
[Objective] This study aimed to optimize the ultrasonic extraction process of total flavonoids from Angelica keiskei Koidzumi. [Method] Using the yield of total flavonoids as an indicator, the ultrasonic extraction pr... [Objective] This study aimed to optimize the ultrasonic extraction process of total flavonoids from Angelica keiskei Koidzumi. [Method] Using the yield of total flavonoids as an indicator, the ultrasonic extraction process of total flavonoids from A. keiskei was optimized by orthogonal experimental design. [ Result ] Among four factors in orthogonal experimental design, extraction time exhibited the most significant effect on the extraction result; ethanol concentration exhib- ited a significant effect on the extraction result; ultrasonic power and solid-to-liquid ratio had no significant effect. The optimal conditions for ultrasonic extraction of total flavonoids from A. keiskei were extraction time of 25 min, ethanol concentration of 80%, ultrasonic power of 60 W, solid-to-liquid ratio of 1:20 (g/ml), under which the yield of total flavonoids reached 1.56%. [ Conclusion] This study provides the basis for further development and utilization of total flavonoids from A. keiskei. 展开更多
关键词 Angelica keiskei Koidzumi Total flavonoids Orthogonal experiment ultrasonic extraction
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Feature extraction of wood-hole defects using wavelet-based ultrasonic testing 被引量:7
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作者 Huiming Yang Lei Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期395-402,共8页
The primary bottleneck to extracting wood defects during ultrasonic testing is the accuracy of identifying the wood defects. The wavelet energy moment was used to extract defect features of artificial wood holes drill... The primary bottleneck to extracting wood defects during ultrasonic testing is the accuracy of identifying the wood defects. The wavelet energy moment was used to extract defect features of artificial wood holes drilled into 120 elm samples that differed in the number of holes to verify the validity of the method. Wavelet energy moment can reflect the distribution of energy along the time axis and the amount of energy in each frequency band,which can effectively extract the energy distribution characteristics of signals in each frequency band; therefore,wavelet energy moment can replace the wavelet frequency band energy and constitute wood defect feature vectors. A principal component analysis was used to normalize and reduce the dimension of the feature vectors. A total of 16 principal component features were then obtained, which can effectively extract the defect features of the different number of holes in the elm samples. 展开更多
关键词 wavelet defects ultrasonic extracting replace validity identifying verify processed bottleneck
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Multiresidue Method for Determination of 67 Pesticides in Water Samples Using Solid-Phase Extraction with Centrifugation and Gas Chromatography-Mass Spectrometry 被引量:3
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作者 Abir Kouzayha Abdul Rahman Rabaa +3 位作者 Mohamad Al Iskandarani Daniel Beh Hélène Budzinski Farouk Jaber 《American Journal of Analytical Chemistry》 2012年第3期257-265,共9页
A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 a... A new multi-residue method based on solid-phase extraction (SPE) with centrifugation was developed for determination and quantitation of 67 pesticides in water samples. Two SPE cartridges were tested: Chromabond C18 and Oasis HLB. Parameters that influence the extraction efficiency such as the eluent volume, the sample loading volume, the addition of organic solvent to water sample, sorbent drying and elute concentration were optimized. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps. When combined with centrifugation, the volume of the elution solvent was reduced to 2 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under the optimized conditions, this method showed good recoveries higher than 65% - 68% for the 67 analyzed pesticides using the C18 and HLB cartridges with relative standard deviations lower than 9.7% - 12.3%. Limits of quantification were between 2 and 20 ng.L–1. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples. 展开更多
关键词 MULTI-RESIDUE PESTICIDES SOLID-PHASE extraction centrifugation Gas Chromatography-Mass SPECTROMETRY
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Ultrasonic Nebulization Extraction Coupled with Gas Chromatography-Mass Spectrometry for Analysis of Volatile Components in Traditional Chinese Patent Medicine 被引量:1
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作者 LIANG Yue WANG Lu WANG Zi-ming YU Cui ZHANG Han-qi SHI Yu-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期203-207,共5页
The ultrasonic nebulization extraction(UNE) was developed and applied to the extraction of volatile components from traditional Chinese patent medicine Xiaoyao Pills. Several parameters of ultrasonic nebulization ex... The ultrasonic nebulization extraction(UNE) was developed and applied to the extraction of volatile components from traditional Chinese patent medicine Xiaoyao Pills. Several parameters of ultrasonic nebulization extraction including the sample particle size, solvent volume, extraction time and ultrasonic power were studied and selected. As a result, 2.4 g of sample with particle size of 80 mesh was extracted with 15 mL of n-hexane for 20 min at an ultrasonic power of 35 W. The volatile components were analyzed by gas chromatography-mass spectrometry (GC-MS) under the optimal conditions and 57 compounds were identified. The precision, repeatability and stability of the proposed method were also studied. Compared with ultrasonic-assisted extraction(UAE) and hydrodistillation(HD) extraction, the proposed method is more efficient, faster and easier to be operated at room temperature with smaller sample and energy consumption. It is suggested that the ultrasonic nebulization extraction can be used as a novel alternative method for the extraction of volatile components from traditional Chinese patent medicine. 展开更多
关键词 ultrasonic nebulization extraction Gas chromatography-mass spectrometry Volatile component Traditional Chinese patent medicine
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FEATURE EXTRACTION OF BONES AND SKIN BASED ON ULTRASONIC SCANNING 被引量:3
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作者 Zheng Shuxian Zhao Wanhua +1 位作者 Lu Bingheng Zhao Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期510-514,共5页
In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning m... In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning method is developed to acquire the bones and skin contours of the residual limb. Using a pig fore-leg as the scanning object, an overlapping algorithm is designed to reconstruct the 2D cross-sectional image, the contours of the bone and skin are extracted using edge detection algorithm and the 3D model of the pig fore-leg is reconstructed by using reverse engineering technology. The results of checking the accuracy of the image by scanning a cylinder work pieces show that the extracted contours of the cylinder are quite close to the standard circumference. So it is feasible to get the contours of bones and skin by ultrasonic scanning. The ultrasonic scanning system featuring no radiation and low cost is a kind of new means of cross section scanning for medical images. 展开更多
关键词 ultrasonic scanning image reconstruction Feature extraction Bones and skin Image accuracy
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A Study on the Ultrasonic Extraction and Antioxidant Activity of Lychee Pericarp Polysaccharides 被引量:1
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作者 Dandan ZHAO Shengyu CHEN +3 位作者 Shaoming LING Bingfang SHI Jinlei ZHANG Li LI 《Asian Agricultural Research》 2016年第7期61-63,68,共4页
The aim was to optimize ultrasonic extraction conditions and study antioxidant activities of lychee pericarp polysaccharides. The effects of extraction temperature,time,ultrasonic power,solid-liquid ratio on polysacch... The aim was to optimize ultrasonic extraction conditions and study antioxidant activities of lychee pericarp polysaccharides. The effects of extraction temperature,time,ultrasonic power,solid-liquid ratio on polysaccharides yield were investigated by single-factor experiment and orthogonal experiment to obtain optimum extraction conditions; the antioxidant activities of lychee pericarp polysaccharides were evaluated by the total antioxidant activity. Optimum extraction process was under extraction temperature of 80 ℃,extraction time of 2. 5 h,ultrasonic power of 180 W,solid-liquid ratio of 1∶ 25 g / m L; the total antioxidant activity was increased with the increasing concentration of polysaccharides. The extraction process is simple and efficient. The extraction rate of lychee pericarp polysaccharides with antioxidant activities is high. 展开更多
关键词 Lychee PERICARP POLYSACCHARIDES ultrasonic extraction ANTIOXIDANT ACTIVITY
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Optimization of Ultrasonic Extraction Process of Polysaccharides from Polyporus umbellatus 被引量:1
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作者 Juanjuan DU Mengting LIU Fei LI 《Agricultural Biotechnology》 CAS 2015年第6期7-9,共3页
[ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbe... [ Objective] This study aimed to investigate the optimal conditions for ultrasonic extraction of polysaccharides from Polyporus umbeUatus, thus providing a reliable basis for the development and utilization of P. umbellatus. [ Method ] By single-factor experiment, the ultrasonic extraction process of polyperus pelysac- charides was optimized. [Result] The optimal conditions for ultrasonic extraction of polysaccharides from P. umbeUatus were: solid-liquid ratio 1:40 (g: ml), ex- traction duration 60 rain, extraction temperature 70 ℃, ultrasonic power 100 W. [ Conclusion] Compared with conventional water extraction method, ultrasonic ex- traction could significantly improve the content of polyporus polysaccharides with shorter extraction duration, lower solid-liquid ratio and lower extraction tempera- 展开更多
关键词 Polyporus umbellatus POLYSACCHARIDES ultrasonic extraction Single-factor experiment
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The Optimization of Ultrasonic Extraction Process of Total Flavonoids from Rhodiola Crenulata by Response Surface Method 被引量:9
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作者 Xuedong GU Yajing SUN +2 位作者 Changzhong MA Fumin CHI Lin YANG 《Medicinal Plant》 2017年第6期33-39,共7页
[Objectives]To study the optimal extraction process of total flavonoids in Rhodiola rosea L.,and further facilitate the development and utilization of Rhodiola rosea L. [Methods]With Rhodiola crenulata as raw material... [Objectives]To study the optimal extraction process of total flavonoids in Rhodiola rosea L.,and further facilitate the development and utilization of Rhodiola rosea L. [Methods]With Rhodiola crenulata as raw material,ethanol as extractant,ultrasonic extraction as the extraction method,the single factor method was first used for preliminary investigation of effect of ethanol volume fraction,solid-liquid ratio,extraction temperature and extraction time on the flavonoids extraction rate,and then the Box-Behnken response surface method was used to optimize the extraction process of total flavonoids in R. crenulata. [Results] The optimal extraction conditions: ethanol concentration of 72%;solid-liquid ratio of 1∶ 43; extraction temperature of 66℃; extraction time of 50 min. Under these conditions,the extraction rate of total flavonoids from R. crenulata was 2. 591%. [Conclusions] The results showed that the method of response surface was reasonable and feasible for the optimization of ultrasonic extraction of total flavonoids from R. crenulata. 展开更多
关键词 RHODIOLA crenulata TOTAL FLAVONOIDS ultrasonic extraction RESPONSE surface method
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