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Phase equilibrium data prediction and process optimizationin butadiene extraction process
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作者 Baowei Niu Yanjie Yi +5 位作者 Yuwen Wei Fuzhen Zhang Lili Wang Li Xia Xiaoyan Sun Shuguang Xiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期1-12,共12页
In response to the lack of reliable physical parameters in the process simulation of the butadiene extraction,a large amount of phase equilibrium data were collected in the context of the actual process of butadiene p... In response to the lack of reliable physical parameters in the process simulation of the butadiene extraction,a large amount of phase equilibrium data were collected in the context of the actual process of butadiene production by acetonitrile.The accuracy of five prediction methods,UNIFAC(UNIQUAC Functional-group Activity Coefficients),UNIFAC-LL,UNIFAC-LBY,UNIFAC-DMD and COSMO-RS,applied to the butadiene extraction process was verified using partial phase equilibrium data.The results showed that the UNIFAC-DMD method had the highest accuracy in predicting phase equilibrium data for the missing system.COSMO-RS-predicted multiple systems showed good accuracy,and a large number of missing phase equilibrium data were estimated using the UNIFAC-DMD method and COSMO-RS method.The predicted phase equilibrium data were checked for consistency.The NRTL-RK(non-Random Two Liquid-Redlich-Kwong Equation of State)and UNIQUAC thermodynamic models were used to correlate the phase equilibrium data.Industrial device simulations were used to verify the accuracy of the thermodynamic model applied to the butadiene extraction process.The simulation results showed that the average deviations of the simulated results using the correlated thermodynamic model from the actual values were less than 2%compared to that using the commercial simulation software,Aspen Plus and its database.The average deviation was much smaller than that of the simulations using the Aspen Plus database(>10%),indicating that the obtained phase equilibrium data are highly accurate and reliable.The best phase equilibrium data and thermodynamic model parameters for butadiene extraction are provided.This improves the accuracy and reliability of the design,optimization and control of the process,and provides a basis and guarantee for developing a more environmentally friendly and economical butadiene extraction process. 展开更多
关键词 Butadiene extraction Phase equilibrium data Prediction methods Thermodynamic modeling process simulation
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TLC Identification and Extraction Process of Rubiasin-1-methyl Ether from Yao Medicine Chuanlianzhu
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作者 Jingrong LU Jiangcun WEI +3 位作者 Xiumei MA Bing QING Meiyan QIU Wen ZHONG 《Medicinal Plant》 2024年第3期35-38,共4页
[Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopte... [Objectives]To establish a thin-layer chromatography(TLC)method for the determination of rubiadin-1-methyl ether in Yao Medicine Chuanlianzhu(Damnacanthus giganteus).[Methods]A silica gel G thin-layer plate was adopted for TLC.Petroleum ether(60-90℃)-chloroform-methanol-water(7:15:3:1)was used as the developing solvent and inspected under ultraviolet lamp(365 nm).The content was determined by Inertsil ODS-3 C 18 column(4.60 mm×250 mm,5μm),mobile phase:acetonitrile-0.2%phosphoric acid gradient elution,detection wavelength 277 nm,flow rate 1.0 mL/min,column temperature 30℃,injection volume 10μL.[Results]The spots of 10 Chuanlianzhu samples from different origins showed the same color at the same position as the control,and the spots were clear and specific.The injection volume of rubiadin-1-methyl ether showed a good linear relationship in the range of 2.90-145μg(R=0.9996).The average recovery rate of rubiadin-1-methyl ether in the low,medium and high dose groups of Yao Medicine Chuanlianzhu was 98.72%,and RSD=1.78%.[Conclusions]This method can effectively identify Yao Medicine Chuanlianzhu medicinal materials and accurately determine the content of rubiadin-1-methyl ether in the medicinal materials.It provides a scientific basis for the development and utilization of Yao Medicine Chuanlianzhu medicinal resources. 展开更多
关键词 Chuanlianzhu THIN-LAYER chromatography (TLC) extraction process Rubiadin-1-methyl ETHER Content determination
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Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts
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作者 Hongsheng LIU Jiqiang YAO +2 位作者 Xue BAI Jianying KANG Yefei YUAN 《Medicinal Plant》 2024年第2期10-14,共5页
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen... [Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh. 展开更多
关键词 Penthorum chinense Pursh Total flavonoids Orthogonal experiments extraction process Content determination
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Mechanism of Rosae Rugosae Flos flavonoids in the treatment of hyperlipidemia and optimization of extraction process based on network pharmacology
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作者 Yunxiao Xia Aijinxiu Ma +1 位作者 Zihan Hou Xu Zhao 《Journal of Polyphenols》 2024年第2期65-77,共13页
This study aims to identify a natural plant chemical with hypolipidemic effects that can be used to treat high cholesterol without adverse reactions.Through network pharmacology screening,it was found that Rosae Rugos... This study aims to identify a natural plant chemical with hypolipidemic effects that can be used to treat high cholesterol without adverse reactions.Through network pharmacology screening,it was found that Rosae Rugosae Flos(RF)flavonoids had potential therapeutic effects on hyperlipidemia and its mechanism of action was discussed.TCMSP and GeneCards databases were used to obtain active ingredients and disease targets.Venn diagrams were drawn to illustrate the findings.The interaction network diagram was created using Cytoscape 3.8.0 software.The PPI protein network was constructed using String.GO and KEGG enrichment analysis was performed using Metascape.The results revealed 2 active flavonoid ingredients and 60 potential targets in RF.The key targets,including CCL2,PPARG,and PPARA,were found to play a role in multiple pathways such as the AGE-RAGE signaling pathway,lipid and atherosclerosis,and cancer pathway in diabetic complications.The solvent extraction method was optimized for efficient flavonoid extraction based on network pharmacology prediction results.This was achieved through a single factor and orthogonal test,resulting in an optimum process with a reflux time of 1.5 h,a solid-liquid ratio of 1:13 g/mL,and an ethanol concentration of 50%. 展开更多
关键词 Rosae Rugosae Flos FLAVONOIDS extraction process optimization network pharmacology HYPERLIPIDEMIA
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A comprehensive review of existing corpora and methods for creating annotated corpora for event extraction tasks
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作者 Mohd Hafizul Afifi Abdullah Norshakirah Aziz +3 位作者 Said Jadid Abdulkadir Kashif Hussain Hitham Alhussian Noureen Talpur 《Journal of Data and Information Science》 CSCD 2024年第4期196-238,共43页
Purpose:The purpose of this study is to serve as a comprehensive review of the existing annotated corpora.This review study aims to provide information on the existing annotated corpora for event extraction,which are ... Purpose:The purpose of this study is to serve as a comprehensive review of the existing annotated corpora.This review study aims to provide information on the existing annotated corpora for event extraction,which are limited but essential for training and improving the existing event extraction algorithms.In addition to the primary goal of this study,it provides guidelines for preparing an annotated corpus and suggests suitable tools for the annotation task.Design/methodology/approach:This study employs an analytical approach to examine available corpus that is suitable for event extraction tasks.It offers an in-depth analysis of existing event extraction corpora and provides systematic guidelines for researchers to develop accurate,high-quality corpora.This ensures the reliability of the created corpus and its suitability for training machine learning algorithms.Findings:Our exploration reveals a scarcity of annotated corpora for event extraction tasks.In particular,the English corpora are mainly focused on the biomedical and general domains.Despite the issue of annotated corpora scarcity,there are several high-quality corpora available and widely used as benchmark datasets.However,access to some of these corpora might be limited owing to closed-access policies or discontinued maintenance after being initially released,rendering them inaccessible owing to broken links.Therefore,this study documents the available corpora for event extraction tasks.Research limitations:Our study focuses only on well-known corpora available in English and Chinese.Nevertheless,this study places a strong emphasis on the English corpora due to its status as a global lingua franca,making it widely understood compared to other languages.Practical implications:We genuinely believe that this study provides valuable knowledge that can serve as a guiding framework for preparing and accurately annotating events from text corpora.It provides comprehensive guidelines for researchers to improve the quality of corpus annotations,especially for event extraction tasks across various domains.Originality/value:This study comprehensively compiled information on the existing annotated corpora for event extraction tasks and provided preparation guidelines. 展开更多
关键词 Information extraction Event extraction Text mining Large language model Natural language processing
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A Joint Entity Relation Extraction Model Based on Relation Semantic Template Automatically Constructed
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作者 Wei Liu Meijuan Yin +1 位作者 Jialong Zhang Lunchong Cui 《Computers, Materials & Continua》 SCIE EI 2024年第1期975-997,共23页
The joint entity relation extraction model which integrates the semantic information of relation is favored by relevant researchers because of its effectiveness in solving the overlapping of entities,and the method of... The joint entity relation extraction model which integrates the semantic information of relation is favored by relevant researchers because of its effectiveness in solving the overlapping of entities,and the method of defining the semantic template of relation manually is particularly prominent in the extraction effect because it can obtain the deep semantic information of relation.However,this method has some problems,such as relying on expert experience and poor portability.Inspired by the rule-based entity relation extraction method,this paper proposes a joint entity relation extraction model based on a relation semantic template automatically constructed,which is abbreviated as RSTAC.This model refines the extraction rules of relation semantic templates from relation corpus through dependency parsing and realizes the automatic construction of relation semantic templates.Based on the relation semantic template,the process of relation classification and triplet extraction is constrained,and finally,the entity relation triplet is obtained.The experimental results on the three major Chinese datasets of DuIE,SanWen,and FinRE showthat the RSTAC model successfully obtains rich deep semantics of relation,improves the extraction effect of entity relation triples,and the F1 scores are increased by an average of 0.96% compared with classical joint extraction models such as CasRel,TPLinker,and RFBFN. 展开更多
关键词 Natural language processing deep learning information extraction relation extraction relation semantic template
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Study on the green extraction of corncob xylan by deep eutectic solvent
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作者 Bingyu Jiao Le Wang +3 位作者 Haitao Gui Zifu Ni Rong Du Yuansen Hu 《Grain & Oil Science and Technology》 CAS 2024年第1期50-59,共10页
Corn as one of the world's major food crops,its by-product corn cob is also rich in resources.However,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other ... Corn as one of the world's major food crops,its by-product corn cob is also rich in resources.However,the unreasonable utilization of corn cob often causes the environmental pollution,waste of resources and other problems.As one of the most abundant polymers in nature,xylan is widely used in food,medicine,materials and other fields.Corn cob is rich in xylan,which is an ideal raw material for extracting xylan.However,the intractable lignin is covalently linked to xylan,which increases the difficulty of xylan extraction.It has been reported that the deep eutectic solvent(DES)could preferentially dissolve lignin in biomass,thereby dissolving the xylan.Then,the xylan in the extract was separated by ethanol precipitation method.The xylan precipitate was obtained after centrifugation,while the supernatant was retained.The components of the supernatant after ethanol precipitation were separated by the rotary evaporator.The ethanol,water and DES were collected for the subsequent extraction of corn cob xylan.In this study,a novel way was provided for the green production of corn cob xylan.The DES was used to extract xylan from corn cob which was used as the raw material.The effects of solid-liquid ratio,reaction time,reaction temperature and water content of DES on the extraction rate of corn cob xylan were investigated by the single factor test.Furthermore,the orthogonal test was designed to optimize the xylan extraction process.The structure of corn cob xylan was analyzed and verified.The results showed that the optimum extraction conditions of corn cob xylan were as follows:the ratio of corn cob to DES was 1:15(g:mL),the extraction time was 3 h,the extraction temperature was 60℃,and the water content of DES was 70%.Under these conditions,the extraction rate of xylan was 16.46%.The extracted corn cob xylan was distinctive triple helix of polysaccharide,which was similar to the structure of commercially available xylan.Xylan was effectively and workably extracted from corn cob by the DES method.This study provided a new approach for high value conversion of corn cob and the clean production of xylan. 展开更多
关键词 CORNCOB Deep eutectic solvent XYLAN process optimization extraction
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Extraction Process and Quality Standard of Danshen Jianxin Capsules 被引量:1
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作者 Chengtong LIU Xinying MO +5 位作者 Silu HE Donglian CHEN Guilin YANG Hongsheng TAN Peng LIANG Haisheng ZENG 《Medicinal Plant》 CAS 2023年第1期25-28,共4页
[Objectives]This study was conducted to establish the quality standard of Danshen Jianxin Capsules.[Methods]Orthogonal design was adopted to optimize the water extraction process by taking the amount of water added,ex... [Objectives]This study was conducted to establish the quality standard of Danshen Jianxin Capsules.[Methods]Orthogonal design was adopted to optimize the water extraction process by taking the amount of water added,extraction time and extraction times as factors,and the content of tanshinone I as the index.Salviae Miltiorrhizae,Notoginseng Radix Et Rhizoma and Radix Astragali in the capsules were qualitatively identified by TLC,and the content of tanshinone I in the capsules was determined by HPLC.[Results]The best water extraction process included the steps of adding 12 times of water each time,extracting the materials twice,for 1 h each time.In TLC identification,the test samples showed spots of the same color at the positions corresponding to tanshinone II A,ginsenoside Rg1,notoginsenoside R1 and astragaloside IV reference samples.[Conclusions]Danshen Jianxin Capsules was prepared by the water extraction method,which is characterized by high efficiency and being suitable for mass production.The quality control method is reliable,fast and accurate,which can effectively control the quality of the product. 展开更多
关键词 Danshen Jianxin Capsules extraction process Content determination TLC identification Quality standard
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Optimization of Polysaccharides Extraction from Physalis alkekengi L.Peel and Its Effect on the Expression of Inflammation-Related Proteins in SW620 Cells
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作者 Dan Shao Chengxin Hao +4 位作者 Yubi Mei Jiaxin Xu Tianjiao Wang Wei Yang Jiamei Wu 《Proceedings of Anticancer Research》 2024年第4期148-156,共9页
Objective:To establish an optimized aqueous extraction process for polysaccharides from Physalis alkekengi L.peel and to preliminarily explore its in vitro anti-inflammatory activity against colorectal cancer SW620 ce... Objective:To establish an optimized aqueous extraction process for polysaccharides from Physalis alkekengi L.peel and to preliminarily explore its in vitro anti-inflammatory activity against colorectal cancer SW620 cells.Methods:A single-factor test combined with orthogonal test analysis was used to evaluate the effects of the material-to-liquid ratio,extraction temperature,and extraction time on the yield of polysaccharides from Physalis alkekengi L.peel.The antioxidant activity of the polysaccharides was assessed by analyzing their free radical scavenging ability in vitro,and the anti-inflammatory effect was evaluated using SW620 cells.Results:The optimal extraction conditions were a material-to-liquid ratio of m(g):V(mL)=1:30,an extraction temperature of 100℃,and an extraction time of 40 minutes,with a predicted polysaccharide yield of 25.7%.The polysaccharides from Physalis peruviana peel effectively scavenged DPPH,superoxide anion,and hydroxyl radicals.After treatment with Physalis peruviana polysaccharides,the levels of IL-1β,IL-18,and TNF-αin the cell culture medium were significantly reduced,and the phosphorylation level of P65 protein in SW620 cells was decreased.Conclusion:This extraction method is stable and reliable,and the prepared Physalis alkekengi L.polysaccharides exhibit significant in vitro antioxidant and anti-inflammatory activities.This study provides a theoretical basis for developing drugs for the prevention and treatment of colorectal cancer. 展开更多
关键词 Physalis alkekengi L.polysaccharide ANTIOXIDANT IL-1β extraction process Colorectal cancer
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Design of Traditional Chinese Medicine Extraction Workshop Process and Automation System
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作者 Meisong Li Dongmei Tan Qian Zhang 《Pharmacology & Pharmacy》 2023年第10期407-427,共21页
Objective: This paper takes the example of a Panax notoginseng extraction workshop and designs an automated production workshop with advanced domestic capabilities. Methods: 1) Based on the small-scale Panax notoginse... Objective: This paper takes the example of a Panax notoginseng extraction workshop and designs an automated production workshop with advanced domestic capabilities. Methods: 1) Based on the small-scale Panax notoginseng extraction process, the feasibility of the workshop production process is demonstrated. 2) The workshop process design for Panax Notoginseng saponin extraction is completed, including production organization plans and the selection of key equipment. 3) For the Panax notoginseng extraction workshop process, an automated production control system is designed. Conclusion: Through optimized design of the production process and automation system, continuous and automated production of traditional Chinese medicine extraction is achieved, leading to improvements in drug quality and production efficiency. 展开更多
关键词 Traditional Chinese Medicine extraction process Validation Panax Notoginseng Saponin Workshop process Design Automation Control
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Extraction Process of Zhuang Medicine Fumigation Lotion
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作者 Jiangcun WEI Meiyan QIU +4 位作者 Bing QING Xianyi SHI Yinghong HUANG Xian PENG Wen ZHONG 《Medicinal Plant》 CAS 2023年第5期29-31,41,共4页
[Objectives]To establish the extraction process and quality standard method of Zhuang medicine fumigation lotion.[Methods]The orthogonal design method was employed to optimize the water extraction process with the amo... [Objectives]To establish the extraction process and quality standard method of Zhuang medicine fumigation lotion.[Methods]The orthogonal design method was employed to optimize the water extraction process with the amount of water added,decocting time and extraction times as factors,and syringin content and dry extract yield as indexes.The content of syringin was determined by high performance liquid chromatography.[Results]The best water extraction process was:soaking in water for 1 h,decocting twice,added 10 times the amount of water each time,decocting for 1 h.The average content of syringin in 3 batches was 0.98 mg/g,and the average dry extract yield was 26.07%.[Conclusions]The project adopts water extraction method to prepare Zhuang medicine fumigation lotion,which has the characteristics of high efficiency and suitable for large-scale production.The quality control method is reliable,rapid and accurate,and can effectively control the quality of the lotion. 展开更多
关键词 Zhuang medicine fumigation lotion extraction process Content determination
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Study on Extraction Process of Phytoene from Tomato Paste
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作者 吴增宝 彭代萍 陈文 《Agricultural Science & Technology》 CAS 2017年第12期2554-2556,2560,共4页
With tomato paste as raw material, the optimal extraction process of phy- toene from tomato paste was explored by orthogonal experiment on the basis of single-factor experiments. The results showed that the optimal ex... With tomato paste as raw material, the optimal extraction process of phy- toene from tomato paste was explored by orthogonal experiment on the basis of single-factor experiments. The results showed that the optimal extraction process for phytoene from tomato paste was as follows: extractant, acetone; solid to liquid ratio, 10:1; extraction time, 40 min; extraction temperature, 45 ℃. The developed extrac- tion process was stable, reasonable and feasible. Under the optimal extraction pro- cess, the extraction rate of phytoene reached 0.044 4%. 展开更多
关键词 Tomato paste PHYTOENE extraction process
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Extraction process of chlorogenic acid in flos lonicerae by enzymatic treatment 被引量:4
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作者 刘佳佳 赵国玲 +1 位作者 王晖 章晓骅 《Journal of Central South University of Technology》 2002年第4期246-249,共4页
A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three... A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three important factors, enzyme dosage, treatment time and treatment temperature are adapted to optimize the extraction process. The experimental results show that the extract yield of flos lonicerae and chlorogenic acid can be obviously increased by the cellulase treatment, 61.5 mg chlorogenic acid is obtained from 1.00 g flos lonicerae at most. The optimal temperature of enzymatic treatment is 40 50 ℃. Compared with the use of single cellulase, the combined treatment of cellulase and pectinase increase the extract yield obviously but fail to improve that of chlorogenic acid. 展开更多
关键词 flos lonicerae chlorogenic ACID ENZYMATIC TREATMENT extract process
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Extraction Process Validation of Isatis Radix 被引量:4
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作者 Junshan Li Bo Zhang 《Pharmacology & Pharmacy》 2014年第4期356-363,共8页
This study is aimed to validate the extraction process of Isatis Radix. Using near infrared spectroscopy and high performance liquid chromatography to determine the uridine, adenosine, guanosine contents in Isatis Rad... This study is aimed to validate the extraction process of Isatis Radix. Using near infrared spectroscopy and high performance liquid chromatography to determine the uridine, adenosine, guanosine contents in Isatis Radix Solution, as well as NIR to monitor the extraction process. The results indicate that the existing extraction is optimized to extract thoroughly. 展开更多
关键词 Isatis RADIX extraction process NIR SPECTROSCOPY HPLC VALIDATION
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Fusion of Region Extraction and Cross-Entropy SVM Models for Wheat Rust Diseases Classification
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作者 Deepak Kumar Vinay Kukreja +2 位作者 Ayush Dogra Bhawna Goyal Talal Taha Ali 《Computers, Materials & Continua》 SCIE EI 2023年第11期2097-2121,共25页
Wheat rust diseases are one of the major types of fungal diseases that cause substantial yield quality losses of 15%–20%every year.The wheat rust diseases are identified either through experienced evaluators or compu... Wheat rust diseases are one of the major types of fungal diseases that cause substantial yield quality losses of 15%–20%every year.The wheat rust diseases are identified either through experienced evaluators or computerassisted techniques.The experienced evaluators take time to identify the disease which is highly laborious and too costly.If wheat rust diseases are predicted at the development stages,then fungicides are sprayed earlier which helps to increase wheat yield quality.To solve the experienced evaluator issues,a combined region extraction and cross-entropy support vector machine(CE-SVM)model is proposed for wheat rust disease identification.In the proposed system,a total of 2300 secondary source images were augmented through flipping,cropping,and rotation techniques.The augmented images are preprocessed by histogram equalization.As a result,preprocessed images have been applied to region extraction convolutional neural networks(RCNN);Fast-RCNN,Faster-RCNN,and Mask-RCNN models for wheat plant patch extraction.Different layers of region extraction models construct a feature vector that is later passed to the CE-SVM model.As a result,the Gaussian kernel function in CE-SVM achieves high F1-score(88.43%)and accuracy(93.60%)for wheat stripe rust disease classification. 展开更多
关键词 Wheat rust diseases AGRICULTURAL region extraction models INTERCROPPING image processing feature extraction precision agriculture
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Extraction Process and Content Determination of Total Flavonoids in Ginkgo( Ginkgo biloba L. ) Leaves 被引量:2
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作者 Dengfeng ZOU Hua ZHU +1 位作者 Binghua QIN Xiaohua WANG 《Agricultural Biotechnology》 CAS 2019年第1期171-175,共5页
[Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavono... [Objectives]This study was conducted to study the extraction process and the content determination of flavonoids in ginkgo( Ginkgo biloba L.) leaves.[Methods]Ethanol extraction and methanol extraction of total flavonoids in ginkgo leaves were studied,and the optimal extraction conditions for flavonoids were determined by orthogonal test; and with quercetin as reference substance,total flavonoid content in ginkgo leaves was determined by UV spectrophotometry.[Results]The optimal extraction process was 4 h of Soxhlet extraction with methanol; and the total flavonoid contents had a good linear relation in the range of 0. 006 5-0. 039 mg/ml( R^2= 0. 999 9),the average content was stabilized at 1. 135%,and the average recovery of the method was 102. 0%. [Conclusions]This study selected the optimal extraction process for total flavonoids in ginkgo leaves. The test method is simple with high accuracy and precision,and is suitable for the extraction and determination of total flavonoids in ginkgo leaves. 展开更多
关键词 GINKGO biloba L. TOTAL FLAVONOIDS extraction process Content determination
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Optimization of Extraction Process of Clerodendrum philippinum Schauer var. simplex Mlodenke Total Flavonoids(CPTF) by Central Composite Design-Response Surface Methodology 被引量:3
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作者 Bo LI Simao HUANG +3 位作者 Xiaohua PANG Boting XI Houkang CAO Kefeng ZHANG 《Medicinal Plant》 CAS 2018年第3期17-20,共4页
[Objectives] The research aimed to optimize extraction process of Clerodendrum philippinum Schauer var. simplex Mlodenke total flavonoids( CPTF),and provide reference for its development and utilization. [Methods] Bas... [Objectives] The research aimed to optimize extraction process of Clerodendrum philippinum Schauer var. simplex Mlodenke total flavonoids( CPTF),and provide reference for its development and utilization. [Methods] Based on single-factor test,ethanol concentration,extraction temperature and extraction time were taken as independent variables,and total flavonoids yield was taken as dependent variable. The test was conducted according to central composite design principle. Multivariate linear regression and binomial equation fitting of the result were conducted,and extraction process of CPTF was optimized by using response surface methodology. [Results]The optimal extraction process of CPTF was as below: ethanol concentration 54. 76%,extraction temperature 83. 92℃,extraction time 102. 64 min,solid-liquid ratio 1:20,extraction for twice. [Conclusions] The extraction process of CPTF by central composite design-response surface methodology was simple and feasible,with reliable prediction result,which was suitable for industrial production. 展开更多
关键词 Central composite design-response surface methodology Guoqiangfeng Total flavonoids extraction process
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Information Extraction Based on Multi-turn Question Answering for Analyzing Korean Research Trends
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作者 Seongung Jo Heung-Seon Oh +2 位作者 Sanghun Im Gibaeg Kim Seonho Kim 《Computers, Materials & Continua》 SCIE EI 2023年第2期2967-2980,共14页
Analyzing Research and Development(R&D)trends is important because it can influence future decisions regarding R&D direction.In typical trend analysis,topic or technology taxonomies are employed to compute the... Analyzing Research and Development(R&D)trends is important because it can influence future decisions regarding R&D direction.In typical trend analysis,topic or technology taxonomies are employed to compute the popularities of the topics or codes over time.Although it is simple and effective,the taxonomies are difficult to manage because new technologies are introduced rapidly.Therefore,recent studies exploit deep learning to extract pre-defined targets such as problems and solutions.Based on the recent advances in question answering(QA)using deep learning,we adopt a multi-turn QA model to extract problems and solutions from Korean R&D reports.With the previous research,we use the reports directly and analyze the difficulties in handling them using QA style on Information Extraction(IE)for sentence-level benchmark dataset.After investigating the characteristics of Korean R&D,we propose a model to deal with multiple and repeated appearances of targets in the reports.Accordingly,we propose a model that includes an algorithm with two novel modules and a prompt.A newly proposed methodology focuses on reformulating a question without a static template or pre-defined knowledge.We show the effectiveness of the proposed model using a Korean R&D report dataset that we constructed and presented an in-depth analysis of the benefits of the multi-turn QA model. 展开更多
关键词 Natural language processing information extraction question answering multi-turn Korean research trends
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Investigation of extraction fraction in confined impinging jet reactors for tri-butyl-phosphate extracting butyric acid process 被引量:2
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作者 Zhengming Gao Manting Zhao +2 位作者 Yun Yu Zhipeng Li Jing Han 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期310-316,共7页
The extraction fraction E and overall volumetric mass transfer coefficient kka of TBP extracting butyric acid pro- cess in confined impinging jet reactors (CIJR) with two jets were investigated. The main variables t... The extraction fraction E and overall volumetric mass transfer coefficient kka of TBP extracting butyric acid pro- cess in confined impinging jet reactors (CIJR) with two jets were investigated. The main variables tested were the concentration of tri-butyl-phosphate (TBP) and butyric acid, the impinging velocity V, the impinging velocityratio of two phases Vorg/Vaq, the nozzle inner diameter di and the distance L between the jet axes and the top wall of the impinging chamber. The results showed that E and kLa increase with an increase of the impinging velocity V, the concentration ofTBP Corg, and the impinging velocity ratio Vor/Vaq. However, E and kta decrease with an increase of the inner diameter d1 from 1 to 2 mm, the concentration of butyric acid Caq from 0.5% (v/v) to 2% (v/v). The factor L ranging from 3 to 11 mm has a negligible effect on E and kLa. A correlation on these variables and kLa was proposed based on the experimental data. These results indicated good mass transfer oerformance of CIJR in the extraction operation. 展开更多
关键词 Confined impinging jet reactors (CIJR) extraction fraction Mass transfer coefficient extraction process
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Optimization of the Extraction Process of Astaxanthin from Haematococcus pluvialis with Oil Dissolution Method 被引量:2
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作者 Xiaohui LI Ning ZOU +1 位作者 Donghong SUN Jun ZHANG 《Agricultural Biotechnology》 CAS 2015年第6期70-72,共3页
[ Objective ] This study aimed to optimize the extraction process of astaxanthin from Haematococcus pluvialis with oil dissolution method. [ Method ] Small amounts of acetone or ethanol were separately added into soyb... [ Objective ] This study aimed to optimize the extraction process of astaxanthin from Haematococcus pluvialis with oil dissolution method. [ Method ] Small amounts of acetone or ethanol were separately added into soybean oil for astaxanthin extraction. The extraction efficiency of astaxanthin from H. pluvialis with different methods was compared. [ Result] The extraction efficiency of astaxanthin from H. pluvialis with acetone, acetone + soybean oil, ethanol + soybean oil, soybean oil was 20.46, 21.65, 20.85 mg/g and 13.05 mg/g, respectively. According to the results, acetone + soybean oil led to the highest extraction rate, which was approximately twice that of soybean oil and higher than that of acetone. [ Conclusion ] This study laid the foundation for large-scale production of astaxanthin. 展开更多
关键词 Haematococcus pluvialis extraction process optimization ASTAXANTHIN 0il dissolution method
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