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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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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 of Fagopyri Dibotryis Rhizoma by Orthogonal Experiment
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作者 Jian YU 《Medicinal Plant》 2024年第3期26-29,共4页
[Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate ... [Objectives]To optimize the water extraction process of Fagopyri Dibotryis Rhizoma.[Methods]The entropy weight method was used to determine the weight of epicatechin extraction rate and dry extract rate and calculate the comprehensive score.The water extraction process of Fagopyri Dibotryis Rhizoma was optimized by orthogonal design with the comprehensive score as the indicator and the amount of water,extraction time and extraction times as the factors.[Results]The optimum extraction process of Fagopyri Dibotryis Rhizoma was as follows:adding 10 times of water,extracting 3 times,and extracting for 60 min each time.[Conclusions]The optimized extraction process is stable and feasible,and can be used for the extraction of Fagopyri Dibotryis Rhizoma. 展开更多
关键词 Fagopyri Dibotryis Rhizoma ORTHOGONAL EXPERIMENT EPICATECHIN DRY EXTRACT
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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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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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Predictive methods for density and refractive index of naphthenic lubricating oils during solvent extraction process 被引量:2
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作者 Xiao-Ling Xu Tian-Qi Wang +2 位作者 Guang-Huai Chen Jun-Wei Hou Yan-Sheng Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1934-1946,共13页
Lubricating oils are usually produced by solvent extraction to separate aromatics in order to achieve the desired specifications and better quality products.Among the different properties of lubricating oils,density a... Lubricating oils are usually produced by solvent extraction to separate aromatics in order to achieve the desired specifications and better quality products.Among the different properties of lubricating oils,density and refractive index are some of the most important properties which can both be used for petroleum fluid characterization.Predictions of density and refractive index for naphthenic oils during solvent extraction by DMSO obtained by the pseudo-component approach and the quadratic correlation were both examined.The pseudo-component approach is a method to predict density and refractive index from composition while the latter merely relates density to refractive index.Results indicated that the predictions yielded by the pseudo-component method were in good agreement with experimental data for naphthenic oils.And the use of a function of refractive index(FRI_(20))as a pseudo-component property remarkably improved n_(20)predictions for the naphthenic mixtures.However,the density and refractive index predictions obtained by the quadratic correlation exhibited significantly higher de-viations for naphthenic oils than those for paraffinic oils.Thus a new modified correlation of the same functional form was proposed for naphthenic oils.The modification significantly improved predictions for naphthenic oils,which presented similar accuracy as the pseudo-component approach.And the previous correlation was still used for paraffinic oils.Additionally,effect of temperature on density and refractive index of naphthenic oils was examined.Results showed that the modified quadratic correlation was accurate for describing the relationship between density and refractive index of naphthenic oils at 20-90℃.The temperature dependence of density and refractive index for the raffinates and the extracts could be accurately described by the thermal coefficients for saturates and aromatics,respectively.Regarding the refractive index variation of the extracts with temperature,the empirical equation was proved to be a better option compared with the method using the thermal coefficient for aromatics. 展开更多
关键词 DENSITY Refractive index Pseudo-components Paraffinic lubricating oils Naphthenic lubricating oils Solvent extraction
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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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Online pharmaceutical process analysis of Chinese medicine using a miniature mass spectrometer: Extraction of active ingredients as an example 被引量:1
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作者 Wangmin Hu Junling Hou +4 位作者 Wenjing Liu Xuan Gu Yulei Yang Hongcai Shang Mei Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第5期535-543,共9页
The automation of traditional Chinese medicine(TCM)pharmaceuticals has driven the development of process analysis from offline to online.Most of common online process analytical technologies are based on spectroscopy,... The automation of traditional Chinese medicine(TCM)pharmaceuticals has driven the development of process analysis from offline to online.Most of common online process analytical technologies are based on spectroscopy,making the identification and quantification of specific ingredients still a challenge.Herein,we developed a quality control(QC)system for monitoring TCM pharmaceuticals based on paper spray ionization miniature mass spectrometry(mini-MS).It enabled real-time online qualitative and quantitative detection of target ingredients in herbal extracts using mini-MS without chromatographic separation for the first time.Dynamic changes of alkaloids in Aconiti Lateralis Radix Praeparata(Fuzi)during decoction were used as examples,and the scientific principle of Fuzi compatibility was also investigated.Finally,the system was verified to work stably at the hourly level for pilot-scale extraction.This mini-MS based online analytical system is expected to be further developed for QC applications in a wider range of pharmaceutical processes. 展开更多
关键词 process analytical technology TCM Pharmaceuticals Miniature mass spectrometry Online analysis
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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 of Cinnamomum longepaniculatum deciduous leaves essential oil using solvent-free microwave extraction: Process optimization and quality evaluation
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作者 Chunlei Wei Chuyun Wan +1 位作者 Fenghong Huang Tingting Guo 《Oil Crop Science》 CSCD 2023年第1期7-15,共9页
The optimal process conditions for solvent-free microwave extraction(SFME)of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodolog... The optimal process conditions for solvent-free microwave extraction(SFME)of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodology(RSM).A Box-Behnken design(BBD)was applied to evaluate the effects of three independent variables:moisture content(A:54%–74%),microwave power(B:300–500 W)and microwave time(C:20–40 min),on the extraction yield of essential oil.The compounds of the essential oils obtained by SFME,hydro-distillation and microwaveassisted hydro-distillation(MADE)were identified by gas chromatography-mass spectrometry(GC-MS),and the total lipids of C.longepaniculatum fresh leaves and deciduous leaves were analyzed.The correlation analysis of the response regression model indicated that quadratic polynomial model could be employed to optimize the extraction of essential oil.The optimal extraction condition was A:58%,B:400 W and C:28 min.In the optimal condition,the maximum extraction yield was 4.475 mL/100 g dw and higher than that by MADE.The main compound of the essential oil was eucalyptol(63.54%),and total oxygenated compounds was 78.95%,mainly caused by SFME and the metabolism of endophytic bacteria with decreasing content of phospholipids and fatty acids.Analysis of variance under the extraction condition illustrated high fitness of the model and the success of RSM for optimizing and reflecting the expected process condition.SFME combined with moisture regulation was an effective method for extracting essential oil from C.longepaniculatum deciduous leaves. 展开更多
关键词 Cinnamomum longepaniculatum Deciduous leaves Solvent-free microwave extraction Response surface methodology extraction yield Essential oil
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Extraction and Refining Process of Polysaccharide from Tricholoma matsutake and Verification of Its Whitening Effect
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作者 Quan AN Guoqing LI +2 位作者 Xuetao LI Ruijun JU Xue SHAO 《Medicinal Plant》 CAS 2023年第1期19-24,共6页
[Objectives]The paper was to determine the extraction and refining process of polysaccharide from Tricholoma matsutake,and to verify its whitening effect.[Methods]With T.matsutake as the research object,the effects of... [Objectives]The paper was to determine the extraction and refining process of polysaccharide from Tricholoma matsutake,and to verify its whitening effect.[Methods]With T.matsutake as the research object,the effects of eluent concentration,loading amount and diameter-to-height ratio on the refining process of T.matsutake polysaccharide were explored by orthogonal test,to optimize the dynamic elution conditions of T.matsutake polysaccharide.The survival rate of mouse melanoma cells(B16),inhibition of melanin synthesis and inhibition of tyrosinase activity of crude extract A1 and refined extracts A2-A4 were tested to verify the whitening effect of T.matsutake.[Results]The best extraction and refining process for T.matsutake polysaccharide was:eluent 40%ethanol(volume fraction),loading amount 30 mg/g(polysaccharide-resin),diameter-to-height ratio 1∶8.Under this condition,the extraction rate of T.matsutake can reach up to 33%(A3).The whitening efficacy test showed that crude extract A1 and refined extracts A2-A4 had good whitening effects,and the whitening effects were A3≥A4>A1>A2.[Conclusions]The study provides a reference for the application of T.matsutake polysaccharide in cosmetics. 展开更多
关键词 Tricholoma matsutake POLYSACCHARIDE extraction PURIFICATION WHITENING
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Automatic Extraction Method of 3D Feature Guidelines for Complex Cultural Relic Surfaces Based on Point Cloud 被引量:1
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作者 GENG Yuxin ZHONG Ruofei +1 位作者 HUANG Yuqin SUN Haili 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期16-41,共26页
Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduct... Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduction is undoubtedly necessary for line drawings.However,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is complex.Therefore,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic projection.Based on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was designed.Then the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index distributions.The feasibility and stability were verified through experiments conducted on real cultural relic surface data.Results demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex surfaces.The extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics. 展开更多
关键词 point cloud conformal parameterization vertex weight surface mesh cultural relics feature extraction
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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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Effect of bubble morphology and behavior on power consumption in non-Newtonian fluids’aeration process 被引量:1
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作者 Xiemin Liu Jing Wan +5 位作者 Jinnan Sun Lin Zhang Feng Zhang Zhibing Zhang Xinyao Li Zheng Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期243-254,共12页
Due to a prolonged operation time and low mass transfer efficiency, the primary challenge in the aeration process of non-Newtonian fluids is the high energy consumption, which is closely related to the form and rate o... Due to a prolonged operation time and low mass transfer efficiency, the primary challenge in the aeration process of non-Newtonian fluids is the high energy consumption, which is closely related to the form and rate of impeller, ventilation, rheological properties and bubble morphology in the reactor. In this perspective, through optimal computational fluid dynamics models and experiments, the relationship between power consumption, volumetric mass transfer rate(kLa) and initial bubble size(d0) was constructed to establish an efficient operation mode for the aeration process of non-Newtonian fluids. It was found that reducing the d0could significantly increase the oxygen mass transfer rate, resulting in an obvious decrease in the ventilation volume and impeller speed. When d0was regulated within 2-5 mm,an optimal kLa could be achieved, and 21% of power consumption could be saved, compared to the case of bubbles with a diameter of 10 mm. 展开更多
关键词 Non-Newtonian fluids aeration process Power consumption Volumetric mass transfer rate Bubble size
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Preferentially selective extraction of lithium from spent LiCoO_(2)cathodes by medium-temperature carbon reduction roasting 被引量:1
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作者 Daixiang Wei Wei Wang +6 位作者 Longjin Jiang Zhidong Chang Hualei Zhou Bin Dong Dekun Gao Minghui Zhang Chaofan Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期315-322,共8页
Lithium recovery from spent lithium-ion batteries(LIBs)have attracted extensive attention due to the skyrocketing price of lithium.The medium-temperature carbon reduction roasting was proposed to preferential selectiv... Lithium recovery from spent lithium-ion batteries(LIBs)have attracted extensive attention due to the skyrocketing price of lithium.The medium-temperature carbon reduction roasting was proposed to preferential selective extraction of lithium from spent Li-CoO_(2)(LCO)cathodes to overcome the incomplete recovery and loss of lithium during the recycling process.The LCO layered structure was destroyed and lithium was completely converted into water-soluble Li2CO_(3)under a suitable temperature to control the reduced state of the cobalt oxide.The Co metal agglomerates generated during medium-temperature carbon reduction roasting were broken by wet grinding and ultrasonic crushing to release the entrained lithium.The results showed that 99.10%of the whole lithium could be recovered as Li2CO_(3)with a purity of 99.55%.This work provided a new perspective on the preferentially selective extraction of lithium from spent lithium batteries. 展开更多
关键词 spent LiCoO_(2)cathodes medium-temperature carbon reduction lithium extraction priority crystal transformation macro-scopic transport resistance
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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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Optimization of Supercritical Extraction Process of Laoshan Black Tea by Response Surface Methodology
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作者 Yongxin LIU Zhiguang LIU +11 位作者 Zengyu WANG Shuai ZHANG Guofeng YU Jianhong SUN Shoutao CAO Qiulin LIU Xulun WEI Cuishu LENG Fuhua MA Xuegang LI Yinlong WANG Shoujie NIE 《Agricultural Biotechnology》 CAS 2023年第1期98-101,共4页
[Objectives]Laoshan black tea was subjected to supercritical CO_(2) extraction. [Methods]The extraction conditions of Laoshan black tea were studied by an orthogonal experiment and optimized by response surface method... [Objectives]Laoshan black tea was subjected to supercritical CO_(2) extraction. [Methods]The extraction conditions of Laoshan black tea were studied by an orthogonal experiment and optimized by response surface methodology. [Results] The optimum extraction conditions of black tea extract by supercritical CO_(2) extraction were as follows: extraction pressure 23.53 MPa, extraction time 1.73 h, and extraction temperature 49.75 ℃, with which the extract yield could reach 5.15% theoretically. [Conclusions] Based on the traditional extraction process, a supercritical extraction method optimized by response surface methodology and a unique extraction process were formed, which enriches the extraction processes and methods of natural raw materials. 展开更多
关键词 Laoshan black tea Supercritical extraction Response surface method
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Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes
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作者 Zhen Zhang Pan Luo +7 位作者 Yan Zhang Yuhan Wang Li Liao Bo Yu Mingshan Wang Junchen Chen Bingshu Guo Xing Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期678-687,共10页
Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low cost.Nevertheless,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines gi... Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low cost.Nevertheless,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental pollution.In this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium extraction.The conductive network in the LFP electrode was optimized by adjusting the type of conductive agent.This approach resulted in high lithium extraction efficiency and extended cycle life.When the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was utilized.Meanwhile,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling performance.When the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical performance.Furthermore,a self-designed,highly efficient,continuous lithium extraction device was constructed.The electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this device.This work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes. 展开更多
关键词 salt lake brine lithium extraction electrochemical lithium extraction conductive agent extraction efficiency adsorption capacity
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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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Unlocking the Potential:A Comprehensive Systematic Review of ChatGPT in Natural Language Processing Tasks
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作者 Ebtesam Ahmad Alomari 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期43-85,共43页
As Natural Language Processing(NLP)continues to advance,driven by the emergence of sophisticated large language models such as ChatGPT,there has been a notable growth in research activity.This rapid uptake reflects in... As Natural Language Processing(NLP)continues to advance,driven by the emergence of sophisticated large language models such as ChatGPT,there has been a notable growth in research activity.This rapid uptake reflects increasing interest in the field and induces critical inquiries into ChatGPT’s applicability in the NLP domain.This review paper systematically investigates the role of ChatGPT in diverse NLP tasks,including information extraction,Name Entity Recognition(NER),event extraction,relation extraction,Part of Speech(PoS)tagging,text classification,sentiment analysis,emotion recognition and text annotation.The novelty of this work lies in its comprehensive analysis of the existing literature,addressing a critical gap in understanding ChatGPT’s adaptability,limitations,and optimal application.In this paper,we employed a systematic stepwise approach following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)framework to direct our search process and seek relevant studies.Our review reveals ChatGPT’s significant potential in enhancing various NLP tasks.Its adaptability in information extraction tasks,sentiment analysis,and text classification showcases its ability to comprehend diverse contexts and extract meaningful details.Additionally,ChatGPT’s flexibility in annotation tasks reducesmanual efforts and accelerates the annotation process,making it a valuable asset in NLP development and research.Furthermore,GPT-4 and prompt engineering emerge as a complementary mechanism,empowering users to guide the model and enhance overall accuracy.Despite its promising potential,challenges persist.The performance of ChatGP Tneeds tobe testedusingmore extensivedatasets anddiversedata structures.Subsequently,its limitations in handling domain-specific language and the need for fine-tuning in specific applications highlight the importance of further investigations to address these issues. 展开更多
关键词 Generative AI large languagemodel(LLM) natural language processing(NLP) ChatGPT GPT(generative pretraining transformer) GPT-4 sentiment analysis NER information extraction ANNOTATION text classification
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