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Optimization of Extraction Conditions for Total Flavonoids from Fructus Aurantii Immaturus and Its Anti-UVB Radiation Activity
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作者 Xu CHANG Yanhui WANG +5 位作者 Ximing LIU Yunge MA Yunhao LIU Xiaobo CHEN Mengyao SUN Liyan LI 《Agricultural Biotechnology》 CAS 2023年第4期110-114,118,共6页
[Objectives]Optimum extraction conditions of total flavonoids from Fructus Aurantii Immaturus(TFFAI)and its resistance activity to ultraviolet radiation were investigated in present research.[Methods]The optimal extra... [Objectives]Optimum extraction conditions of total flavonoids from Fructus Aurantii Immaturus(TFFAI)and its resistance activity to ultraviolet radiation were investigated in present research.[Methods]The optimal extraction conditions of TFFAI were determined by single factor and orthogonal experiments,and the survival rate of TFFAI on HaCaT cells irradiated with UVB rays was investigated.It s antioxidant capacity was determined by ABTS.[Results]The results showed that the highest yield of TFFAI was obtained with 70%ethanol at a solid-to-liquid ratio of 1:50(w/v)and 40℃for 1.5 h by single-factor and orthogonal experiments.Total flavonoids(0.25-1.00 mg/ml)could significantly improve the survival rate of HaCaT cell line.Meanwhile,the maximum absorption peak of TFFAI was found at 283 nm,and in-vitro antioxidant experiment identified that TFFAI had a good clearance rate to ABTS.It suggestes that TFFAI could protect the cells from UVB damage by absorption of UVB rays and anti-oxidation.[Conclusions]TFFAI played a protective role on UVB irradiated cells through UVB ultraviolet absorption and antioxidant pathways. 展开更多
关键词 Fructus Aurantss Immaturus Total flavonoids Optimization of extraction conditions UVB radiation resistance
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Optimization of Extraction Conditions of Pomegranate Peel Polyphenols and Its Protective Effect on Acute Alcoholic Liver Injury in Mice
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作者 Dianwu KONG Miao CAI +4 位作者 Jing LI Xinyu HAO Xinhao YANG Xianglong WANG Liyan LI 《Agricultural Biotechnology》 CAS 2023年第4期16-21,40,共7页
[Objectives]This study was conducted to explore the optimization of ultrasonic-assisted organic solvent extraction of pomegranate peel polyphenols(PPPs),and to study the protective effect of PPPs on acute alcoholic li... [Objectives]This study was conducted to explore the optimization of ultrasonic-assisted organic solvent extraction of pomegranate peel polyphenols(PPPs),and to study the protective effect of PPPs on acute alcoholic liver injury in mice.[Methods]The optimal extraction conditions of PPPs were determined by single factor and orthogonal experiments,and an acute alcoholic liver injury model in mice was established.Bifendate was used as the positive control group to investigate the protective effect of low,medium and high doses of PPPs on acute alcoholic liver injury.[Results]The optimum extraction process parameters were followed as 60%ethanol concentration,solid-liquid ratio of 1:40(w/v),extraction temperature of 50℃,and extraction time of 1.5 h,and the yield was 1.42%.The results of animal experiments showed that PPPs could effectively reduce the degree of alcoholic liver injury in mice,reduce the levels of serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST),and reduce the inflammation and necrosis of liver tissue in mice.Meanwhile,the total polyphenols from pomegranate peel also significantly reduced the expression levels of malondialdehyde(MDA),tumor necrosis factor(TNF-α)and interleukin-6(IL-6)in mice,and increased the levels of superoxide dismutase(SOD)and reduced glutathione(GSH)in liver tissue of mice,indicating its antioxidant and anti-inflammatory effects,further illustrating its protective effect on alcoholic liver injury.[Conclusions]PPPs could reduce the expression levels of TNF-α,IL-6 and MDA in mice,and increase the expression levels of SOD and GSH to achieve the protective effect on acute alcoholic liver injury in mice.This study will provide new ideas for the development of new anti-alcoholic liver injury drug resources. 展开更多
关键词 Pomegranate peel polyphenols extraction condition optimization Alcoholic liver injury Oxidative stress Inflammatory factor
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Polysaccharides in Sipunculus nudus: Extraction Condition Optimization and Antioxidant Activities 被引量:5
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作者 ZHANG Qin DONG Lanfang +2 位作者 TONG Tong WANG Qingchao XU Mingzhu 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期74-80,共7页
Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxi... Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxidant activities of soluble polysaccharides from the body wall of Sipunculus nudus. The effects of solid-liquid ratio, extraction duration, extraction temperature, and alkali concentration on the yield of S. nudus polysaccharides(SNP) were examined, according to which the optimal combination of extraction parameters was obtained by an orthogonal test. The relative influencing importance of different extraction parameters on the yield of SNP followed the order as solid-liquid ratio > extraction temperature > alkali concentration > extraction duration. The highest extraction yield, 1.98%, was achieved under an optimal extraction condition: temperature 60℃, solid-liquid ratio 1:6 g mL^(-1), duration 5 h, and alkali(Na OH) mass fraction 6%. The in vitro antioxidant activities examination showed that extracted SNP under this optimized condition had strong power in reducing certain hydroxyl and superoxide radical scavenging abilities. The promising results showed that extracted SNP could be a potent natural antioxidant. 展开更多
关键词 Sipunculus nudus POLYSACCHARIDE extraction condition ANTIOXIDANT ACTIVITIES
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Feature Extraction Method Based on Pseudo-Wigner-Ville Distribution for Rotational Machinery in Variable Operating Conditions 被引量:8
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作者 WANG Huaqing LIKe +1 位作者 SUN Hao CHEN Peng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期661-668,共8页
In the case of fault diagnosis for roller bearings, the conventional diagnosis approaches by using the time interval of energy impacts in time-frequency distribution or the pass-frequencies are based on the assumption... In the case of fault diagnosis for roller bearings, the conventional diagnosis approaches by using the time interval of energy impacts in time-frequency distribution or the pass-frequencies are based on the assumption that machinery operates under a constant rotational speed. However, when the rotational speed varies in the broader range, the pass-frequencies vary with the change of rotational speed and bearing faults cannot be identified by the interval of impacts. Researches related to automatic diagnosis for rotational machinery in variable operating conditions were quite few. A novel automatic feature extraction method is proposed based on a pseudo-Wigner-Ville distribution (PWVD) and an extraction of symptom parameter (SP). An extraction method for instantaneous feature spectrum is presented using the relative crossing information (RCI) and sequential inference approach, by which the feature spectrum from time-frequency distribution can be automatically, sequentially extracted. The SPs are considered in the frequency domain using the extracted feature spectrum to identify among the conditions of a machine. A method to obtain the synthetic symptom parameter is also proposed by the least squares mapping (LSM) technique for increasing the diagnosis sensitivity of SP. Practical examples of diagnosis for bearings are given in order to verify the effectiveness of the proposed method. The verification results show that the features of bearing faults, such as the outer-race, inner-race and roller element defects have been effectively extracted, and the proposed method can be used for condition diagnosis of a machine under the variable rotational speed. 展开更多
关键词 feature extraction pseudo-wigner-ville distribution variable operating condition sequential diagnosis
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Inquiry of Water-Soluble Polysaccharide Extraction Conditions from Grapefruit Skin 被引量:9
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作者 Ziping Luo Zilin Liu +3 位作者 Shiyu Tan Qiliang Xu Haiyan Yang Lingli Yang 《Engineering(科研)》 2011年第11期1090-1094,共5页
Water-soluble polysaccharide was isolated from grapefruit with the method of water-dissolving and ethanol-precipitating. By single factor test and orthogonal experimental method, the extraction conditions of the water... Water-soluble polysaccharide was isolated from grapefruit with the method of water-dissolving and ethanol-precipitating. By single factor test and orthogonal experimental method, the extraction conditions of the water-soluble polysaccharide were investigated, which contained liquid-solid ratio, temperature, time and pH. The results showed that pH was the most important factor of polysaccharide extraction, followed by temperature. The optimized extraction technology conditions were obtained. The liquid-solid ratio was 1:40, temperature was 90?C, time was 2.0 h, and pH was 2. The highest extraction rate of crude polysaccharide was 8.30%. 展开更多
关键词 GRAPEFRUIT WATER-SOLUBLE POLYSACCHARIDE extractING condition Single Factor EXPERIMENT and Orthogonal EXPERIMENT
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Optimization of Extraction Conditions of Some Phenolic Compounds from White Horehound (<i>Marrubium vulgare</i>L.) Leaves 被引量:2
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作者 Karim Bouterfas Zoheir Mehdadi +3 位作者 Djamel Benmansour Meghit Boumedien Khaled Mohamed Bouterfas Ali Latreche 《International Journal of Organic Chemistry》 2014年第5期292-308,共17页
This research was aimed to optimize the extraction conditions of three phenolic compounds: total phenolics, flavonoids and condensed tannins, from White Horehound’s leaves (Marrubium vulgare L.). Distilled water and ... This research was aimed to optimize the extraction conditions of three phenolic compounds: total phenolics, flavonoids and condensed tannins, from White Horehound’s leaves (Marrubium vulgare L.). Distilled water and different organic solvents such as: methanol, ethanol and acetone, were used, with various concentrations (20% - 80%, v/v), temperatures (20&deg;C - 60&deg;C) and extraction times (30 - 450 min). Results showed that the maximum total phenolics amounts (293.34 ± 14.60 mg gallic acid equivalent/g dry weigh), were obtained with 60% aqueous methanol at 25&deg;C for 180 min;total flavonoids (79.52 ± 0.55 mg catechin equivalent/g dry weigh) with 80% aqueous methanol at 20&deg;C for 450 min, and condensed tannins (28.15 ± 0.80 mg catechin equivalent/g dry weigh) with 60% aqueous acetone at 50&deg;C and for 180 min. ANOVA test showed the significant effect (***P < 0.001) of the extraction conditions tested on phenolic compounds. The Principal Component Analysis (PCA) exhibited the positive effect of low temperatures on total phenolics and flavonoids extraction, and the effect of high temperatures on the condensed tannins extraction. The Response Surface Methodology (RSM) provided predicted values of extraction conditions and maximum polyphenols amounts similar to those obtained experimentally. 展开更多
关键词 Marrubium vulgare PHENOLIC COMPOUNDS Optimization extraction conditions
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Massive Power Device Condition Monitoring Data Feature Extraction and Clustering Analysis using MapReduce and Graph Model 被引量:4
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作者 Hongtao Shen Peng Tao +1 位作者 Pei Zhao Hao Ma 《CES Transactions on Electrical Machines and Systems》 CSCD 2019年第2期221-230,共10页
Effective storage,processing and analyzing of power device condition monitoring data faces enormous challenges.A framework is proposed that can support both MapReduce and Graph for massive monitoring data analysis at ... Effective storage,processing and analyzing of power device condition monitoring data faces enormous challenges.A framework is proposed that can support both MapReduce and Graph for massive monitoring data analysis at the same time based on Aliyun DTplus platform.First,power device condition monitoring data storage based on MaxCompute table and parallel permutation entropy feature extraction based on MaxCompute MapReduce are designed and implemented on DTplus platform.Then,Graph based k-means algorithm is implemented and used for massive condition monitoring data clustering analysis.Finally,performance tests are performed to compare the execution time between serial program and parallel program.Performance is analyzed from CPU cores consumption,memory utilization and parallel granularity.Experimental results show that the designed framework and parallel algorithms can efficiently process massive power device condition monitoring data. 展开更多
关键词 Clustering analysis GRAPH feature extraction MAPREDUCE maxcompute power device condition monitoring.
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Studies on Optimal Extraction Conditions of Flavonoid in Leaves of Black Currnt 被引量:1
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作者 XUYa-qin SUNYan-mei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第2期144-148,共5页
Employing the orthogonal design,the optimal extraction conditions for flavonoid in leaves of black currant were determined by colorimetric estimation,which were extraction agent of 75% EtOH-H 2O,the material ratio(ra... Employing the orthogonal design,the optimal extraction conditions for flavonoid in leaves of black currant were determined by colorimetric estimation,which were extraction agent of 75% EtOH-H 2O,the material ratio(ratio of weight of fresh leaves to volume of the solvent)of 1:16,the temperature of 35℃,the time of 1 h and times of three.A total extraction rate of over 97% and the flavonoid contents of 179 33 mg/100 g were obtained under the optimal extraction conditions. 展开更多
关键词 extraction conditions flavonoid contents leaves of black currant
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Reaction condition optimization and kinetic investigation of roasting zinc oxide ore using (NH_4)_2SO_4 被引量:7
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作者 Hong-mei Shao Xiao-yi Shen +2 位作者 Yi Sun Yan Liu Yu-chun Zhai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第10期1133-1140,共8页
An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using(NH_4)_2SO_4. The optimized reaction conditions are defined as an(NH_4)_2SO_4/zinc molar ratio of 1.4:1, a roasting ... An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using(NH_4)_2SO_4. The optimized reaction conditions are defined as an(NH_4)_2SO_4/zinc molar ratio of 1.4:1, a roasting temperature of 440°C, and a thermostatic time of 60 min. The molar ratio of(NH_4)_2SO_4/zinc is the most predominant factor and the roasting temperature is the second significant factor that governs the zinc extraction. Thermogravimetric-differential thermal analysis was used for(NH_4)_2SO_4 and zinc mixed in a molar ratio of 1.4:1 at the heating rates of 5, 10, 15, and 20 K·min-1. Two strong endothermic peaks indicate that the complex chemical reactions occur at approximately 290°C and 400°C. XRD analysis was employed to examine the transformations of mineral phases during roasting process. Kinetic parameters, including reaction apparent activation energy, reaction order, and frequency factor, were calculated by the Doyle-Ozawa and Kissinger methods. Corresponding to the two endothermic peaks, the kinetic equations were obtained. 展开更多
关键词 zinc ore treatment extractive metallurgy kinetic studies reaction mechanisms phase transformation reaction conditions
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Optimization of Extraction Process for Polysaccharides of Urtica fissa E. Pritz. 被引量:1
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作者 Lin YANG Duo CAO +1 位作者 Xuedong GU Fumin CHI 《Medicinal Plant》 CAS 2018年第2期44-47,共4页
[Objectives] To study the optimal extraction process for polysaccharides of Urtica fissa E. Pritz. [Methods] Leaves of wild U. fissa E. Pritz. collected in Nyingchi of Tibet were used as raw materials. Water extractio... [Objectives] To study the optimal extraction process for polysaccharides of Urtica fissa E. Pritz. [Methods] Leaves of wild U. fissa E. Pritz. collected in Nyingchi of Tibet were used as raw materials. Water extraction method was used to extract polysaccharides from U. fissa E. Pritz. Besides,comparison was made for the effects of extraction time,extraction temperature and solid-to-liquid ratio on the yield rate of polysaccharides from U. fissa E. Pritz. In addition,using the extraction time,extraction temperature and solid-to-liquid ratio as factors,L9( 33) orthogonal experiment was carried out to determine the optimal process parameters for water extraction of polysaccharides from U. fissa E. Pritz.[Results] The optimal process parameters: hot water extraction time was 4 h,the extraction temperature was 90℃,and the mass ratio of water to leaves of U. fissa E. Pritz. was 1∶ 25. Under such extraction conditions,the yield rate of polysaccharides from U. fissa E. Pritz.was up to 11. 611%. [Conclusions]This experiment is expected to provide certain reference for reasonable development and utilization of wild U. fissa E. Pritz. resources in Tibet. 展开更多
关键词 Urtica fissa E.Pritz. POLYSACCHARIDES extraction Process conditions
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Study on Extraction of Pectin from Orange Peels 被引量:1
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作者 Hongrui LI Yahui HAN +1 位作者 Liqiang ZOU Wenquan ZHANG 《Agricultural Biotechnology》 CAS 2013年第3期30-32,35,共4页
The comparison was conducted to investigate the higher extraction rate between two methods including alcohol deposition with acid hydrolysis and micro- wave-assistant extraction technique. The experimental results sho... The comparison was conducted to investigate the higher extraction rate between two methods including alcohol deposition with acid hydrolysis and micro- wave-assistant extraction technique. The experimental results showed that the former method led to a better extraction effect. For the method of alcohol deposition with acid hydrolysis, the technique parameters were optimized through I.s (34 ) orthogonal e^periment based on the results of single factor experiments, after investi- gated the effect of solid to liquid ratio, pH, extraction temperature and extraction time on the pectin extraction rate. tersrm technique was employed to extract pectin. The selected parameter was obtained by means On the basis of the optimal technical parmne- of L16 (45) orthogonal experiment after studied the effect of solid to liquid ratio, extraction temperature, microwave treatment period, pH and microwave power on pectin extraction yield. Repetitive examinations of two methods were carried out separately, pectin extraction rate with the fLrst technique was 14.57% and that with the second method was 11.62%. The charac- teristics of the pectin sample prepared by alcohol deposition with acid hydrolysis were further investigated. The research demonstrated that mass percent of pectin was 87.23%. The esterification degree of pectin was 75.66% ,and pectin sample color was from creamy white to pale yellow. 展开更多
关键词 Orange peel Pectin Microwave-assistant extraction Optional conditions Methoxy pectin
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EXTRACTION OF ANTHRAQUINONE DERIVATIVES FROM RHUBARB RHIZOMES AND THEIR ANTIBACTERIAL TESTS 被引量:1
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作者 YUAN-CHENG CAO YUAN-DI ZHAO 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2011年第2期127-132,共6页
Photometry was employed to study the optimum extraction conditions of anthraquinone derivatives from rhizomes of Rheum officinale Baill in this study.The influences of extraction solvents(chloroform,benzene,ethanol,me... Photometry was employed to study the optimum extraction conditions of anthraquinone derivatives from rhizomes of Rheum officinale Baill in this study.The influences of extraction solvents(chloroform,benzene,ethanol,methanol,and glycerol),acid,and extraction time on the extraction yield were discussed.The results indicate that,to the Rhubarb rhizomes powder with the average particle size 0.18 mm,the conditions of the extraction solvent composed by chloroform,glycerol,and sulfuric acid(20%)in the ratio of 4:1:1(v:v),the weight of dried Rhubarb to the solvent volume in the ratio of 1:12 ew:vT,extraction time of 110 min,the anthraquinone derivatives extraction could achieve the best yield.And the antibacterial tests showed the raw extraction products had the MIC(minimal inhibitory concentration)of 20μg=mL and 30μg=mL to Staphylococcus aureus and Escherichia coli,respectively. 展开更多
关键词 Anthraquinone derivatives PHOTOMETRY optimum extraction conditions Rheum officinale Baill ANTIBACTERIAL
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Robust Speech Recognition System Using Conventional and Hybrid Features of MFCC,LPCC,PLP,RASTA-PLP and Hidden Markov Model Classifier in Noisy Conditions 被引量:7
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作者 Veton Z.Kepuska Hussien A.Elharati 《Journal of Computer and Communications》 2015年第6期1-9,共9页
In recent years, the accuracy of speech recognition (SR) has been one of the most active areas of research. Despite that SR systems are working reasonably well in quiet conditions, they still suffer severe performance... In recent years, the accuracy of speech recognition (SR) has been one of the most active areas of research. Despite that SR systems are working reasonably well in quiet conditions, they still suffer severe performance degradation in noisy conditions or distorted channels. It is necessary to search for more robust feature extraction methods to gain better performance in adverse conditions. This paper investigates the performance of conventional and new hybrid speech feature extraction algorithms of Mel Frequency Cepstrum Coefficient (MFCC), Linear Prediction Coding Coefficient (LPCC), perceptual linear production (PLP), and RASTA-PLP in noisy conditions through using multivariate Hidden Markov Model (HMM) classifier. The behavior of the proposal system is evaluated using TIDIGIT human voice dataset corpora, recorded from 208 different adult speakers in both training and testing process. The theoretical basis for speech processing and classifier procedures were presented, and the recognition results were obtained based on word recognition rate. 展开更多
关键词 Speech Recognition Noisy conditions Feature extraction Mel-Frequency Cepstral Coefficients Linear Predictive Coding Coefficients Perceptual Linear Production RASTA-PLP Isolated Speech Hidden Markov Model
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Fractional Envelope Analysis for Rolling Element Bearing Weak Fault Feature Extraction 被引量:6
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作者 Jianhong Wang Liyan Qiao +1 位作者 Yongqiang Ye YangQuan Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第2期353-360,共8页
The bearing weak fault feature extraction is crucial to mechanical fault diagnosis and machine condition monitoring.Envelope analysis based on Hilbert transform has been widely used in bearing fault feature extraction... The bearing weak fault feature extraction is crucial to mechanical fault diagnosis and machine condition monitoring.Envelope analysis based on Hilbert transform has been widely used in bearing fault feature extraction. A generalization of the Hilbert transform, the fractional Hilbert transform is defined in the frequency domain, it is based upon the modification of spatial filter with a fractional parameter, and it can be used to construct a new kind of fractional analytic signal. By performing spectrum analysis on the fractional envelope signal, the fractional envelope spectrum can be obtained. When weak faults occur in a bearing, some of the characteristic frequencies will clearly appear in the fractional envelope spectrum. These characteristic frequencies can be used for bearing weak fault feature extraction.The effectiveness of the proposed method is verified through simulation signal and experiment data. 展开更多
关键词 Fractional analytic signal fractional envelope analysis fractional Hilbert transform rolling element bearing weak fault feature extraction
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Optimization of Extraction and Characterization of Pectin from Grapefruit Peels
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作者 Wenbo ZHANG Hongrui LI +3 位作者 Jiulong XIE Wenquan ZHANG Yongxiang XIONG Wenwen ZHOU 《Agricultural Biotechnology》 CAS 2015年第6期34-37,共4页
In this study, pectin was extracted from grapefruit peels with hydrochloric acid and precipitated with 95% ethanol solution and 5% tartaric acid. The physical and chemical properties of pectin obtained were analyzed, ... In this study, pectin was extracted from grapefruit peels with hydrochloric acid and precipitated with 95% ethanol solution and 5% tartaric acid. The physical and chemical properties of pectin obtained were analyzed, including color, texture, degree of esterification, and water solubility. The effects of peel to sol- vent ratio, pH of the solvent, extraction temperature and extraction duration on pectin extraction rate were investigated. On the basis of single-factor experiments, an L9 (34) orthogonal experiment was performed to screen the optimal extraction conditions. According to the results, the optimal combination of technical parame- ters was A1B3 C1 D3, i. e. , solid to liquid ratio 1:40 (g: ml), pH 2.0, extraction duration 70 rain, extraction temperature 90 ℃. The average pectin extraction rate was 68.60% ; the color of pectin extracted under the optimal conditions varied from milky white to light yellow; the degree of esterification of pectin extracts was 65. 71% ; the extracted pectin exhibited good water solubility. Key words Pomelo peel; Pectin extraction; Optimum conditions; Esterification degree; Water solubility 展开更多
关键词 Pomelo peel Pectin extraction Optimum conditions Esterification degree Water solubility
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Application of Particle Swarm Optimization to Fault Condition Recognition Based on Kernel Principal Component Analysis 被引量:1
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作者 WEI Xiu-ye PAN Hong-xia HUANG Jin-ying WANG Fu-jie 《International Journal of Plant Engineering and Management》 2009年第3期129-135,共7页
Panicle swarm optimization (PSO) is an optimization algorithm based on the swarm intelligent principle. In this paper the modified PSO is applied to a kernel principal component analysis ( KPCA ) for an optimal ke... Panicle swarm optimization (PSO) is an optimization algorithm based on the swarm intelligent principle. In this paper the modified PSO is applied to a kernel principal component analysis ( KPCA ) for an optimal kernel function parameter. We first comprehensively considered within-class scatter and between-class scatter of the sample features. Then, the fitness function of an optimized kernel function parameter is constructed, and the particle swarm optimization algorithm with adaptive acceleration (CPSO) is applied to optimizing it. It is used for gearbox condi- tion recognition, and the result is compared with the recognized results based on principal component analysis (PCA). The results show that KPCA optimized by CPSO can effectively recognize fault conditions of the gearbox by reducing bind set-up of the kernel function parameter, and its results of fault recognition outperform those of PCA. We draw the conclusion that KPCA based on CPSO has an advantage in nonlinear feature extraction of mechanical failure, and is helpful for fault condition recognition of complicated machines. 展开更多
关键词 particle swarm optimization kernel principal component analysis kernel function parameter feature extraction gearbox condition recognition
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A Novel Aquila Optimizer Based PV Array Reconfiguration Scheme to Generate Maximum Energy under Partial Shading Condition
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作者 Dong An Junqing Jia +4 位作者 Wenchao Cai Deyu Yang Chao Lv Jiawei Zhu Yingying Jiao 《Energy Engineering》 EI 2022年第4期1531-1545,共15页
This paper develops a real-time PV arrays maximum power harvesting scheme under partial shading condition(PSC)by reconfiguring PV arrays using Aquila optimizer(AO).AO is based on the natural behaviors of Aquila in cap... This paper develops a real-time PV arrays maximum power harvesting scheme under partial shading condition(PSC)by reconfiguring PV arrays using Aquila optimizer(AO).AO is based on the natural behaviors of Aquila in capturing prey,which can choose the best hunting mechanism ingeniously and quickly by balancing the local exploitation and global exploration via four hunting methods of Aquila:choosing the searching area through high soar with the vertical stoop,exploring in different searching spaces through contour flight with quick glide attack,exploiting in convergence searching space through low flight with slow attack,and swooping through walk and grabbing prey.In general,PV arrays reconfiguration is a problem of discrete optimization,thus a series of discrete operations are adopted in AO to enhance its optimization performance.Simulation results based on 10 cases under PSCs show that the mismatched power loss obtained by AO is the smallest compared with genetic algorithm,particle swarm optimization,ant colony algorithm,grasshopper optimization algorithm,and butterfly optimization algorithm,which reduced by 4.34%against butterfly optimization algorithm. 展开更多
关键词 PV array reconfiguration partial shading condition Aquila optimizer maximum power extraction total-cross-tied
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Optimization of Extraction Process and Anti-ultraviolet Activity of Polysaccharide from Cordyceps militaris
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作者 Duofei WANG Mengzhen DING +1 位作者 Huijuan ZHANG Liyan LI 《Agricultural Biotechnology》 CAS 2021年第2期89-92,共4页
Extraction process of Cordyceps militaris polysaccharide(PS)was optimized with single factor experiment and orthogonal test.Then,the anti-UVB ability of the polysaccharide was investigated to develop anti-UV sun-scree... Extraction process of Cordyceps militaris polysaccharide(PS)was optimized with single factor experiment and orthogonal test.Then,the anti-UVB ability of the polysaccharide was investigated to develop anti-UV sun-screening agent through determining the cell viability after UVB irradiation.The results showed that the optimum were solid-liquid ratio at 1∶40(g/ml)at 80℃ for 4 h,and the extract ratio was 27.4%according to the verification test.The PS showed no cytotoxicity to HaCaT cells and pretreatment with the PS significantly decreased UVB-induced cytotoxicity in a dose-dependent relationship.It suggests that the PS has strong anti-UVB irradiation ability and has a good application prospect in developing sunscreen agent. 展开更多
关键词 Cordyceps militaris POLYSACCHARIDE Optimization of extraction conditions Anti-UV radiation
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Study on Leaching Conditions of Miao Medicine Xiange Zuyu Powder
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作者 Yuanfeng YANG Yuchuan LI +2 位作者 Renhui YANG Lida CHEN Qiqian CHEN 《Agricultural Biotechnology》 CAS 2022年第3期103-105,共3页
[Objectives]This study was conducted to optimize the soaking conditions of Miao medicine Xiange Zuyu Powder.[Methods]With the water-soluble extract as an investigation index,an L_(9)(3^(4))orthogonal test was carried ... [Objectives]This study was conducted to optimize the soaking conditions of Miao medicine Xiange Zuyu Powder.[Methods]With the water-soluble extract as an investigation index,an L_(9)(3^(4))orthogonal test was carried out to investigate the amount of water added,soaking temperature,soaking times and soaking time,and the best soaking conditions for Xiange Zuyu Powder were screened.[Results]The optimal soaking conditions were as follows:adding 1000 ml of boiling water at 100℃,soaking for 20 min each time,3 times in total.[Conclusions]The soaking scheme is reasonable and can provide a reasonable basis for clinical medication. 展开更多
关键词 Xiange Zuyu Powder Soaking conditions Orthogonal test Water soluble extract
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Enhanced Identifying Gene Names from Biomedical Literature with Conditional Random Fields
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作者 Wei-Zhong Qian Chong Fu Hong-Rong Cheng Qiao Liu Zhi-Guang Qin 《Journal of Electronic Science and Technology of China》 2009年第3期227-231,共5页
Identifying gene names is an attractive research area of biology computing. However, accurate extraction of gene names is a challenging task with the lack of conventions for describing gene names. We devise a systemat... Identifying gene names is an attractive research area of biology computing. However, accurate extraction of gene names is a challenging task with the lack of conventions for describing gene names. We devise a systematical architecture and apply the model using conditional random fields (CRFs) for extracting gene names from Medline. In order to improve the performance, biomedical ontology features are inserted into the model and post processing including boundary adjusting and word filter is presented to solve name overlapping problem and remove false positive single words. Pure string match method, baseline CRFs, and CRFs with our methods are applied to human gene names and HIV gene names extraction respectively in 1100 abstracts of Medline and their performances are contrasted. Results show that CRFs are robust for unseen gene names. Furthermore, CRFs with our methods outperforms other methods with precision 0.818 and recall 0.812. 展开更多
关键词 conditional random fields gene nameextraction information extraction named entityrecognition
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