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USDE:An Unsupervised Web Data Extraction Method Based on Statistical Characteristics
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作者 Sun Long 《China Communications》 2025年第9期307-319,共13页
Web data extraction has become a key technology for extracting valuable data from websites.At present,most extraction methods based on rule learning,visual pattern or tree matching have limited performance on complex ... Web data extraction has become a key technology for extracting valuable data from websites.At present,most extraction methods based on rule learning,visual pattern or tree matching have limited performance on complex web pages.Through ana-lyzing various statistical characteristics of HTML el-ements in web documents,this paper proposes,based on statistical features,an unsupervised web data ex-traction method—traversing the HTML DOM parse tree at first,calculating and generating the statistical matrix of the elements,and then locating data records by clustering method and heuristic rules that reveal in-herent links between the visual characteristics of the data recording areas and the statistical characteristics of the HTML nodes—which is both suitable for data records extraction of single-page and multi-pages,and it has strong generality and needs no training.The ex-periments show that the accuracy and efficiency of this method are equally better than the current data extrac-tion method. 展开更多
关键词 cluster method statistical feature unsupervised technique web information extraction
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins 被引量:3
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作者 Antonio Pizzi Marie-Pierre Laborie Zeki Candan 《Journal of Renewable Materials》 EI CAS 2024年第3期397-425,共29页
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ... Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses. 展开更多
关键词 TANNINS FLAVONOIDS SOURCES extraction methods analysis methods
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A Review of Joint Extraction Techniques for Relational Triples Based on NYT and WebNLG Datasets
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作者 Chenglong Mi Huaibin Qin +1 位作者 Quan Qi Pengxiang Zuo 《Computers, Materials & Continua》 2025年第3期3773-3796,共24页
In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to er... In recent years,with the rapid development of deep learning technology,relational triplet extraction techniques have also achieved groundbreaking progress.Traditional pipeline models have certain limitations due to error propagation.To overcome the limitations of traditional pipeline models,recent research has focused on jointly modeling the two key subtasks-named entity recognition and relation extraction-within a unified framework.To support future research,this paper provides a comprehensive review of recently published studies in the field of relational triplet extraction.The review examines commonly used public datasets for relational triplet extraction techniques and systematically reviews current mainstream joint extraction methods,including joint decoding methods and parameter sharing methods,with joint decoding methods further divided into table filling,tagging,and sequence-to-sequence approaches.In addition,this paper also conducts small-scale replication experiments on models that have performed well in recent years for each method to verify the reproducibility of the code and to compare the performance of different models under uniform conditions.Each method has its own advantages in terms of model design,task handling,and application scenarios,but also faces challenges such as processing complex sentence structures,cross-sentence relation extraction,and adaptability in low-resource environments.Finally,this paper systematically summarizes each method and discusses the future development prospects of joint extraction of relational triples. 展开更多
关键词 Relation triplet extraction joint extraction methods named entity recognition relation extraction
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Optimization of Extraction Process of Qingdu Jianpi Mixture by Orthogonal Experimental Design
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作者 Jiangcun WEI Bing QING +4 位作者 Jinqing PENG Xiaofen FENG Weiwei CHEN Wen ZHONG Zujie QIN 《Medicinal Plant》 2025年第3期10-14,共5页
[Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin cont... [Objectives]To optimize the optimal extraction process of Qingdu Jianpi Mixture.[Methods]Taking water addition ratio,extraction time and extraction times as process investigation factors,psoralen content,astilbin content and dry extract yield as evaluation indicators,the main influencing factors and level range of the extraction process of Qingdu Jianpi Mixture were determined on the basis of single factor test method,and the optimal weight coefficient was screened by AHP-entropy method mixed with weighting method.Combined with L_(9)(3^(4))orthogonal experiment,the best extraction process was obtained.At the same time,thin-layer chromatographic identification was used to identify Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal liquid.[Results]The best extraction process:add 1:12 water to the prescription decoction pieces,extract under reflux for 2 times,1.5 h per time,and combine the filtrate to 250 mL.Thin layer chromatography analysis showed that the spots of Ficus simplicissima Lour.and Smilax glabra Roxb.in the medicinal solution were the same as those of reference substances at the corresponding positions,and the negative control had no interference.[Conclusions]The experimental method is reasonable and feasible,and the process is reliable,which can provide experimental reference for the subsequent application of in-hospital preparations and research and development of Qingdu Jianpi Mixture. 展开更多
关键词 Qingdu Jianpi MIXTURE AHP-entropy method ORTHOGONAL design extraction PROCESS
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Innovative Approaches in the Extraction,Identification,and Application of Secondary Metabolites from Plants
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作者 Amine Assouguem Saoussan Annemer +1 位作者 Mohammed Kara Abderrahim Lazraq 《Phyton-International Journal of Experimental Botany》 2025年第6期1631-1668,共38页
Unlike primary metabolites,secondary metabolites serve critical ecological functions,including plant protection,stress tolerance,and symbiosis.This review focuses on extracting,separating,and identifying the major cla... Unlike primary metabolites,secondary metabolites serve critical ecological functions,including plant protection,stress tolerance,and symbiosis.This review focuses on extracting,separating,and identifying the major classes of secondary metabolites,including alkaloids,terpenoids,phenolics,glycosides,saponins,and coumarins.It describes optimized methods regarding plant selection,extraction by solvents,and purification of the metabolites,highlighting the latest advancements in chromatographic and spectroscopic techniques.The review also describes some of the most important problems,such as the instability of the compounds or diversity of the structures,and discusses emerging technologies that solve these issues.Moreover,it examines the secondary roles of these metabolites in medicine,such as anticancer and antimicrobial drugs,sustainable agriculture biopesticides,and environmental ecology-also known as allelopathy and bioindicators.It combines traditional ethnobotanical approaches with contem-porary science,demonstrating the vital need to protect biodiversity in key ecosystems such as tropical rainforests,mountain regions,coral reefs,and arid zones as a foundation for anticipatory bio-discoveries.It organizes the methodological frameworks and outlines the steps needed to enhance the extraction of bioactive compounds from natural sources. 展开更多
关键词 Plant-derived substances extraction methods spectroscopic methods climate-friendly farming ecological roles biodiversity preservation
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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
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作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation Regional large-scale Online recognition Feature extraction method
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Isolation of Chlorella vulgaris and Its DNA Extraction Methods 被引量:8
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作者 王恒强 孔庆军 +2 位作者 任雪艳 占东霞 张海黎 《Agricultural Science & Technology》 CAS 2008年第4期44-46,共3页
[Objective] The aim of this study is to isolate Chlorella vulgaris(chlorella)and extract its genomic DNA.[Method] Both the dilution method and drip method were employed to isolate chlorella from lake water samples;the... [Objective] The aim of this study is to isolate Chlorella vulgaris(chlorella)and extract its genomic DNA.[Method] Both the dilution method and drip method were employed to isolate chlorella from lake water samples;the conditions for culturing chlorella were optimized and its genomic DNA was extracted by improved CTAB method and SDS method.[Result] The proper conditions for chlorella culture were as following:temperature 20-25 ℃,illumination 4.39-5.86 W/m2 and rotational speed 100-150r/min;improved CTAB method was suitable for extracting genomic DNA from chlorella.[Conclusion] The study is helpful to study the chlorella at molecular level and promote the exploitation and utilization of chlorella resources. 展开更多
关键词 CHLORELLA VULGARIS ISOLATION method DNA extraction method
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Comparative Study on Four Methods for Quick Extraction of Sorghum Genomic DNA 被引量:3
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作者 高建明 夏卜咸 +5 位作者 杨洪 曲荣桂 桂枝 罗峰 裴忠有 孙守钧 《Agricultural Science & Technology》 CAS 2011年第5期686-687,744,共3页
[Objective] This study was to find out a quick,simple,and low-cost method for the extraction of sorghum genomic DNA.[Method] Four plant genomic DNA extraction methods based on CTAB,including liquid nitrogen grinding m... [Objective] This study was to find out a quick,simple,and low-cost method for the extraction of sorghum genomic DNA.[Method] Four plant genomic DNA extraction methods based on CTAB,including liquid nitrogen grinding method(method I),buffer grinding method(method II),drying grinding method(method III)and directly grinding method(method IV),were used to extract the sorghum genomic DNA from leaves;further the quantity and quality of the yielded DNA were detected by gel electrophoresis,SSR-PCR and SRAP-PCR.[Result] These four methods performed no remarkable difference in DNA product.The method I and method II produced DNA with higher purity and better integrity,which,especially from method I,is effective for SRAP-PCR and SSR-PCR.While the DNA extracted via method III and method IV had less integrality and lower purity,and only effective in SSR-PCR.[Conclusion] Enough amount of sorghum genomic DNA to perform tens of PCR could be quickly extracted using all these four methods.The DNA obtained via method I and method II had a broader application spectrum(SRAP,RAPD,ISSR and SSR)than that via method III and method IV which is only proper for PCR targeting small DNA fragments(SSR). 展开更多
关键词 Sorghum bicolor LEAF Genomic DNA CTAB method Quick extraction
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Comparison of RNA Extraction Methods of Sugarcane Stem 被引量:5
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作者 陈萍 罗挺 蔡文伟 《Agricultural Science & Technology》 CAS 2010年第3期43-46,共4页
[Objective] The study was to explore the most effective and feasible method for sugarcane stalks RNA extraction.[Method] SDS extraction method,kit extraction method and GHCL extraction method were used to extract the ... [Objective] The study was to explore the most effective and feasible method for sugarcane stalks RNA extraction.[Method] SDS extraction method,kit extraction method and GHCL extraction method were used to extract the sugarcane RNA in stalks,and the quality of the extracted RNA was compared.[Result] RNA extracted by kit extraction method had a high-yield,the bands were clear and RNA had a good integrity,there was no significant degradation of RNA,and the OD260 nm/OD280 nm value was closed to 2.0.[Conclusion] Kit extraction method was the effectively method to extract sugarcane RNA,and this study had provided a theoretical basis for the molecular biology study of sugarcane. 展开更多
关键词 SUGARCANE STALK RNA extraction method
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Comparison on Four Extraction Methods of Genomic DNA from Clematis fasciculiflora Franch 被引量:3
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作者 胡祎晨 孙正海 +3 位作者 王锦 李世峰 辛培尧 范萱 《Agricultural Science & Technology》 CAS 2011年第10期1420-1423,共4页
[Objective] This study aimed at comparing the four extraction methods of genomic DNA from Clematis fasciculiflora Franch and determining the optimal extraction method for extracting the genomic DNA from Clematis fasci... [Objective] This study aimed at comparing the four extraction methods of genomic DNA from Clematis fasciculiflora Franch and determining the optimal extraction method for extracting the genomic DNA from Clematis fasciculiflora Franch.[Method] Leavies of Clematis fasciculiflora Franch were used as materials for comparing the purity and concentration of extracted DNA and extracting time among the four extraction methods of genomic DNA including improved CTAB method Ⅰ,improved CTAB method Ⅱ,improved CTAB method Ⅲ and improved SDS method.[Result] The four extraction methods could all be successfully used for extracting the genomic DNA from Clematis fasciculiflora Franch.The purity of genomic DNA was the highest using improved CTAB method Ⅰ,with the longest extracting time;while the concentration of genomic DNA was the maximum using the improved SDS method,with the shortest extracting time and relatively low purity;the extracting time of improved CTAB method Ⅲ was the shortest.[Conclusion] This study had established the optimal extraction method for extracting the genomic DNA from Clematis fasciculiflora Franch and supported for the further research using molecular biological methods. 展开更多
关键词 Clematis fasciculiflora Franch extraction of genomic DNA Improved CTAB method Improved SDS method
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Comparison of Genomic DNA Extraction Methods for Chenopodium quinoa Willd 被引量:4
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作者 陆敏佳 莫秀芳 +2 位作者 王勤 陆国权 蒋玉蓉 《Agricultural Science & Technology》 CAS 2015年第7期1343-1347,1446,共6页
To rapidly obtain high-quality genomic DNA from Chenopodium quinoa Willd, the genomic DAN in different tissues (leaves, stems and roots) of Chenopodi- um quinoa Willd was extracted by modified CTAB method, SDS metho... To rapidly obtain high-quality genomic DNA from Chenopodium quinoa Willd, the genomic DAN in different tissues (leaves, stems and roots) of Chenopodi- um quinoa Willd was extracted by modified CTAB method, SDS method and high- salt Iow-pH method, respectively. The quality and yield of extracted DNA was deter- mined using agarose gel electrophoresis and UV spectrophotometry. At the same time, the PCR-SSR and SSCP molecular detection was also performed. The results showed that the gel test strips, without obvious decomposition, of all the extraction methods were relatively obvious; the genomic DNA yield extracted by modified CTAB method was highest, followed by that by SDS method, and the genomic DNA extracted by high-salt Iow-pH method was lowest: the genomic DNA yields extracted by different methods from Chenopodium quinoa Wiltd leaves were all high- er than those from roots and stems; the quality of Chenopodium quinoa Willd ge- nomic DNA extracted by modified CTAB method and high-salt Iow-pH method was better, and polyphenols, polysaccharides and other impurities were removed more completely. The PCR-SSR and SSCP detection results showed that the genomic DNA extracted by different methods from different tissues of Chenopodium quinoa Willd all could be better amplified, and high-quality strips could be obtained. So the Chenopodium quinoa Willd genomic DNA extracted by the three methods all can be used for subsequent molecular biology research. 展开更多
关键词 Chenopodium quinoa Willd DNA extraction method Molecular detection SSR: SSCP
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Extraction of Pumpkin Polysaccharide by Complex Enzyme Method and Its Antioxidant Research 被引量:20
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作者 孙婕 尹国友 +2 位作者 陈兰英 Guo-you Lan-ying 《Agricultural Science & Technology》 CAS 2010年第5期34-37,共4页
[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid rati... [Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin. [Method] The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogonal tests. Scavenging ·OH and O-2 activities of pumpkin polysaccharides were also investigated by salicylic acid and improved self-oxidation of o-pheno methods respectively. [Results] The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min under water at 40 ℃ with the solid-liquid ratio of 1:30. In addition,pumpkin polysaccharides had a strong activity of eliminating ·OH,but very weak activity to scavenge O-2. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide. 展开更多
关键词 Complex enzymes method Pumpkin polysaccharide extraction Antioxidant activity
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Optimization for supercritical CO_2 extraction of icariin by response surface method 被引量:1
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作者 关雅琼 张曜武 张龙 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第2X期159-163,共5页
The aim of the present study was to optimize the supercritical CO_2 extraction conditions of icariin from Herba Epimedii by response surface method(RSM) and central composite design(CCD).A 3-factor,5-level CCD was use... The aim of the present study was to optimize the supercritical CO_2 extraction conditions of icariin from Herba Epimedii by response surface method(RSM) and central composite design(CCD).A 3-factor,5-level CCD was used for the optimization.Independent variables were extraction temperature,extraction pressure and entrainer flow rate.Dependent variable was yield ratio of icariin from Herba Epimedii.A two-order polynomial equation was fitted to the data.The results showed that the optimum extraction conditions were as follows:extraction temperature 46.5℃,extraction pressure 30.6 MPa,entrainer flow rate 3.3 mL/min.CCD/ RSM is convenient and highly predictive for optimizing the extraction process of icariin from Herba Epimedii. 展开更多
关键词 Response surface method Central composite design Supercritical fluid extraction Herba Epimedii ICARIIN
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A New Rapid and Batch-oriented Crushing Method for DNA Extraction from Maize Leaves
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作者 刘鹏飞 陈趣 +2 位作者 曾慕衡 王晓明 蒋锋 《Agricultural Science & Technology》 CAS 2015年第5期945-946,950,共3页
The crushing of leaves is the most time and effort-consuming part in DNA extraction which is a fundamental step in the study of molecular biology. In this study, a new rapid and batch-oriented crushing method for DNA ... The crushing of leaves is the most time and effort-consuming part in DNA extraction which is a fundamental step in the study of molecular biology. In this study, a new rapid and batch-oriented crushing method for DNA extraction from maize leaves was developed. In addition, the practicability of the developed method in molecular marker-assisted breeding was verified using SSR molecular maker technology so as to provide a rapid, batch-oriented, low-cost and non-toxic leafcrushing method for a large number of molecular marker tests, improving test efficiency. 展开更多
关键词 DNA extraction SSR molecular marker MAIZE Rapid and batch-oriented crushing method
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An Improved Method for DNA Extraction from the Faeces of Red Deer
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作者 日沙来提·吐尔地 艾斯卡尔·买买提 +2 位作者 日孜汗·阿布地艾尼 阿米拉·阿布来提 马合木提·哈力克 《Agricultural Science & Technology》 CAS 2012年第4期698-700,900,共4页
[Objective] To introduce an improved method for DNA extraction from the faeces of red deer. [Method] Based on the traditional method of CTAB lysis, we proposed an improved DNA extraction method according to the charac... [Objective] To introduce an improved method for DNA extraction from the faeces of red deer. [Method] Based on the traditional method of CTAB lysis, we proposed an improved DNA extraction method according to the characteristics of red deer faeces. [Result] This improved method extracted high-quality fecal DNA from Tianshan red deer and amplified the mitochondrial cytochrome b gene. With the muscle and fur DNA of red deer as the control, the sequencing results further con- firmed the reliability of the method. [Conclusion] The method requires no proteinase K in the process of extraction, and the extracted DNA can be used for PCR ampli- fication directly without the purification of DNA purification kit, thus, it is cost-saving. 展开更多
关键词 Red deer Noninvasive sampling Improved method for DNA extraction Faecal DNA
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A Mass and Rapid Method for DNA Extraction of Beauveria bassiana
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作者 王滨 岛津光明 《Plant Diseases and Pests》 CAS 2010年第3期19-21,46,共4页
[Objective] The aim was to optimize the mass and rapid method for DNA extraction of Beauvena bassiana. [Method] Boiling water DNA extraction method was improved, DNA extraction liquid was heated by PCR instrument and ... [Objective] The aim was to optimize the mass and rapid method for DNA extraction of Beauvena bassiana. [Method] Boiling water DNA extraction method was improved, DNA extraction liquid was heated by PCR instrument and the extraction process was finished rapidly. [ Resuit] The quality of DNA obtained through mass and rapid extraction of fungal genomic DNA could meet the requirement of RAPD amplification analysis. The clear bands were amplified from 22 tested strains, the number of clear bands were different in the range of 2 -6 and the size of band were mainly concentrated in 450 -800 bp. The DNA extracted by this method also could completely meet the requirement of SCAR amplification. The amplified specific DNA bands used to mark the strain F263 were very clear. [Conclusion] This research provided relatively perfect method for mass and rapid extraction of fungal clenomic DNA. 展开更多
关键词 Beauveria bassiana DNA extraction Boiling water method
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A Comparative Study on Three Methods for the Extraction of Total RNA from Pinus bungeana 被引量:3
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作者 王雁 李贞 +3 位作者 刘小侠 倪慧 毛红 张青文 《Agricultural Science & Technology》 CAS 2011年第5期663-665,共3页
[Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction ... [Objective] The aim of this study was to compare three RNA extraction methods and thus find out the suitable one for isolating intact and high quality total RNA from Pinus bungeana.[Method] Employing three extraction methods of Trizol,RNeasy Mini Kit,LiCl precipitation,total RNAs of P.bungeana were extracted from pine leaf samples,and their integrity and purity were detected via agarose gel electrophoresis and spectrophotometry for a comparative study.[Result] Among the three extraction methods,LiCl precipitation method demonstrated higher yield and better integrity of total extracted RNA,with OD260/OD280 ratio between 1.8-2.0 and clear 28 S and 18 S bands in electrophoresis pattern.[Conclusion] LiCl precipitation method could be used to extract highly pure and intact total RNA from P.bungeana. 展开更多
关键词 Pinus bungeana Total RNA extraction method cDNA library
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DNA extraction of birch leaves by improved CTAB method and optimization of its ISSR system 被引量:10
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作者 PAN hua YANG Chuan-ping WEI Zhi-gang JIANG Jing 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期298-300,共3页
The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitabl... The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitable not only for genomic DNA extraction of birch but also for that of other plants. The purity of genornic DNA extracted by the.multi-times STE-CTAB extraction method is higher than that by one time STE-CTAB method, and it does not need the process of RNase. The factors of influencing ISSR system were explored based on the genomic DNA of birch extracted by the two methods. The optimal conditions for ISSR system were determined as follows: Mg2+ concentration is 1.5-3.0 mmol·L^-1, dNTP concentration 0.104).25 mmol·L^-1, the quantity of Taq polymerase 0.5-2.0 U, template DNA 30-100 ng, and the concentration of primer is 0.2-0.4 pmmol·L^-1, and the reaction program was as: initial denaturation for 5 min at 94℃, 30 cycles of denaturation for 30 s at 94℃,annealing for 30 s at 51℃, extension for 30 s at 72℃, and a final 7 min extension at 72℃. 展开更多
关键词 BIRCH DNA extraction method ISSR Reaction system
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Supervised descent method for weld pool boundary extraction during fiber laser welding process 被引量:6
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作者 Zhao Yaobang Zhang Dengming +1 位作者 Wu Yuanfeng Yang Changqi 《China Welding》 EI CAS 2019年第1期6-10,共5页
In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainl... In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainless steel is welded by a 5 kW high-power fiber laser and a high-speed camera is employed to capture the topside images of weld pools. Then we propose a robust visual-detection approach for the molten pool based on the supervised descent method. It provides an elegant framework for representing the outline of a weld pool and is especially efficient for weld pool detection in the presence of strong uncertainties and disturbances. Finally, welding experimental results verified that the proposed approach can extract the weld pool boundary accurately, which will lay a solid foundation for controlling the weld quality of fiber laser welding process. 展开更多
关键词 fiber laser WELDING MOLTEN POOL supervised DESCENT method BOUNDARY extraction
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CTAB-silica Method for DNA Extraction and Purification from Castanea mollissima and Ginkgo biloba 被引量:7
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作者 Shen Yongbao Shi Jisen 《Forestry Studies in China》 CAS 2003年第3期10-12,共3页
A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Bo... A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Boom et al. (1990). By modifying the protocol, plant genome DNA could be extracted easily from dormant buds, mature leaves, and other parts of plant. Our results showed that the purified DNA was of high purity and could be analyzed by PCR. Furthermore, this CTAB-silica method took much less time for a successful DNA purification process compared to the traditional methods (CTAB and SDS). By our method, the suitable DNA can be extracted and purified from over 10 plant samples by one person in an hour. 展开更多
关键词 DNA extraction and purification CTAB-silica method Castanea mollissima Ginkgo biloba
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