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Environmental,economic and exergy analysis of separation of ternary azeotrope by variable pressure extractive distillation based on multi-objective optimization
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作者 Peizhe Cui Jiafu Xing +5 位作者 Chen Li Mengjin Zhou Jifu Zhang Yasen Dai Limei Zhong Yinglong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期145-157,共13页
In this work,the ternary azeotrope of tert-butyl alcohol/ethyl acetate/water is separated by extractive distillation(ED)to recover the available constituents and protect the environment.Based on the conductor like shi... In this work,the ternary azeotrope of tert-butyl alcohol/ethyl acetate/water is separated by extractive distillation(ED)to recover the available constituents and protect the environment.Based on the conductor like shielding model and relative volatility method,ethylene glycol was selected as the extractant in the separation process.In addition,in view of the characteristic that the relative volatility between components changes with pressure,the multi-objective optimization method based on nondominated sorting genetic algorithm II optimizes the pressure and the amount of solvent cooperatively to avoid falling into the optimal local solution.Based on the optimal process parameters,the proposed heat-integrated process can reduce the gas emissions by 29.30%.The heat-integrated ED,further coupled with the pervaporation process,can reduce gas emission by 42.36%and has the highest exergy efficiency of 47.56%.In addition,based on the heat-integrated process,the proposed two heat pump assisted heat-integrated ED processes show good economic and environmental performance.The double heat pump assisted heat-integrated ED can reduce the total annual cost by 28.78%and the gas emissions by 55.83%compared with the basis process,which has a good application prospect.This work provides a feasible approach for the separation of ternary azeotropes. 展开更多
关键词 extractive distillation Optimization MIXTURES SEPARATION
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The Oxyalkylation of Hydrophilic Black Alder Bark Extractives with Propylene Carbonate with a Focus on Green Polyols Synthesis
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作者 Alexandr Arshanitsa Matiss Pals +1 位作者 Daniela Godina Oskars Bikovens 《Journal of Renewable Materials》 EI CAS 2024年第11期1927-1948,共22页
The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and l... The isolated hydrophilic black alder(Alnus glutinosa)bark extractives were characterized in terms of component and functional composition and converted at 150℃-170℃ into liquid green polyols using solvent-free and lowtoxic base-catalyzed modification with propylene carbonate(PC).FTIR spectroscopy,HP-LC,GC,GPC,and wet chemistry methods were used to characterize the starting constituents,intermediate and final products of the reaction and to monitor the different pathways of PC conversion.The reaction of extractives as well as the model compounds,including catechol,xylose,PEG 400,and benzoic acid,with PC indicated the ability of OH groups of different origins present in the extractives to condense with equivalent amounts of PC.The polyols obtained consist of a copolymer fraction with one oxypropyl unit grafted per OH functionality of extractive components on average and oligo oxypropyl diols with a small number of carbonate linkages in the chain,obtained as a result of remaining PC homopolymerization.The domination of the oxypropylation mechanism vs.transcarbonation for PC ring opening was observed for both copolymerization and homopolymerization processes,making the process of oxypropylation with PC similar to that of conventional oxypropylation.At optimal reaction conditions,including a PC/OH ratio of 3.0 and a 24-h duration at 150°C,uniform polyols with low viscosity of~900 mPa·s^(-1),a biomass content of~27%,and an OHV of~500 mg KOH·g^(-1) were obtained.Increasing the temperature of modification allows shortening the process but drastically increases the polyol viscosity.At fixed temperature values,increasing the PC/OH ratio not only decreases the biomass content but also strongly prolongs the processing.The significantly increased duration of the process using PC as an alternative oxyalkylation agent compared to that of oxyalkylation with propylene oxide is a reasonable trade-off for using a safer and more environmentally friendly technology. 展开更多
关键词 Bark extractives propylene carbonate OXYALKYLATION POLYOLS
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Design of dual-functional protic porous ionic liquids for boosting selective extractive desulfurization
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作者 Jin-Rui Zhang Jie Yin +6 位作者 Jing He Hong-Shun Ran Wei Jiang Hong-Ping Li Wen-Shuai Zhu Hua-Ming Li Ming Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2817-2829,共13页
Porous ionic liquids have demonstrated excellent performance in the field of separation,attributed to their high specific surface area and efficient mass transfer.Herein,task-specific protic porous ionic liquids(PPILs... Porous ionic liquids have demonstrated excellent performance in the field of separation,attributed to their high specific surface area and efficient mass transfer.Herein,task-specific protic porous ionic liquids(PPILs)were prepared by employing a novel one-step coupling neutralization reaction strategy for extractive desulfurization.The single-extraction efficiency of PPILs reached 75.0%for dibenzothiophene.Moreover,adding aromatic hydrocarbon interferents resulted in a slight decrease in the extraction efficiency of PPILs(from 45.2%to 37.3%,37.9%,and 33.5%),indicating the excellent extraction selectivity of PPILs.The experimental measurements and density functional theory calculations reveal that the surface channels of porous structures can selectively capture dibenzothiophene by the stronger electrophilicity(Eint(HS surface channel/DBT)=-39.8 kcal mol^(-1)),and the multiple extraction sites of ion pairs can effectively enrich and transport dibenzothiophene from the oil phase into PPILs throughπ...π,C-H...πand hydrogen bonds interactions.Furthermore,this straightforward synthetic strategy can be employed in preparing porous liquids,offering new possibilities for synthesizing PPILs with tailored functionalities. 展开更多
关键词 Protic porous ionic liquids extractive desulfurization SELECTIVITY Density functional theory
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Economy, environmental assessment and energy conservation for separation of isopropanol/diisopropyl ether/water multi-azeotropes via extractive distillation coupled pervaporation process 被引量:2
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作者 Qinggang Xu Yasen Dai +6 位作者 Qing Zhao Zhengrun Chen Peizhe Cui Zhaoyou Zhu Yinglong Wang Jun Gao Yixin Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期353-363,共11页
This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heteroge... This wok proposed the extraction distillation coupled pervaporation(ED+PV) technology process using two different solvents to separate isopropanol(IPA) and diisopropyl ether(DIPE) from DIPE/IPA/H_(2)O ternary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study.Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol(EG)-EG+H_(2)O process and the 1,3-propanediol(PDO)-IPA+H_(2)O process, the total annual cost(TAC) of the EG-IPA+H_(2)O process decreased by 20.76% and 7.86%(PDO). Compared to the EG-EG+H_(2)O process, the TAC of the PDO-IPA+H_(2)O process reduced 14%, but the global warming potential(GWP) and human toxicity of the PDO-IPA+H_(2)O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H_(2)O process, the EG-IPA+H_(2)O process saves 7.86%(TAC), 9.78%(GWP) and 9.85%(human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H_(2)O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmental assessment and human toxicity, designing cleaner products, controlling waste discharge, and promoting the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical production, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry. 展开更多
关键词 Life cycle assessment extractive distillation coupled pervaporation Isopropanol/diisopropyl ether/water azeotropes Thermodynamic efficiency Human toxicity
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Ginkgo biloba extract alleviates fatty liver hemorrhagic syndrome in laying hens via reshaping gut microbiota 被引量:3
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作者 Xinyue Yang Depeng Li +5 位作者 Meihong Zhang Yuqing Feng Xiaolu Jin Dan Liu Yuming Guo Yongfei Hu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期277-294,共18页
Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatt... Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatty liver hemorrhagic syndrome(FLHS)in laying hens and the underlying mechanisms remain to be elucidated.Here,we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.Results The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet(HFD)-induced FLHS laying hen model by decreasing the levels of TG,TC,ALT and ALP.The lipid accumulation and pathological score of liver were also relieved after GBE treatment.Moreover,GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH,SOD,T-AOC,GSH-PX and reducing MDA,and downregulated the expression of genes related to lipid synthesis(FAS,LXRα,GPAT1,PPARγand Ch REBP1)and inflammatory cytokines(TNF-α,IL-6,TLR4 and NF-κB)in the liver.Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota,particularly elevated the abundance of Megasphaera in the cecum.Meanwhile,targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs,acetate and propionate,which were positively correlated with the GBE-enriched gut microbiota.Finally,we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation(FMT).Conclusions We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota.Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry. 展开更多
关键词 ANTIOXIDATION Fecal microbiota transplantation FLHS Ginkgo biloba extract INFLAMMATION Megasphaera
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Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells 被引量:3
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作者 Yijun Yao Zhifang Li +2 位作者 Bowen Qin Xingrong Ju Lifeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期454-461,共8页
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat... Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4. 展开更多
关键词 Highland barley Polyphenols extract Lipid-lowering effect HepG2 cells
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins 被引量:2
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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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Feature extraction for machine learning-based intrusion detection in IoT networks 被引量:1
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作者 Mohanad Sarhan Siamak Layeghy +2 位作者 Nour Moustafa Marcus Gallagher Marius Portmann 《Digital Communications and Networks》 SCIE CSCD 2024年第1期205-216,共12页
A large number of network security breaches in IoT networks have demonstrated the unreliability of current Network Intrusion Detection Systems(NIDSs).Consequently,network interruptions and loss of sensitive data have ... A large number of network security breaches in IoT networks have demonstrated the unreliability of current Network Intrusion Detection Systems(NIDSs).Consequently,network interruptions and loss of sensitive data have occurred,which led to an active research area for improving NIDS technologies.In an analysis of related works,it was observed that most researchers aim to obtain better classification results by using a set of untried combinations of Feature Reduction(FR)and Machine Learning(ML)techniques on NIDS datasets.However,these datasets are different in feature sets,attack types,and network design.Therefore,this paper aims to discover whether these techniques can be generalised across various datasets.Six ML models are utilised:a Deep Feed Forward(DFF),Convolutional Neural Network(CNN),Recurrent Neural Network(RNN),Decision Tree(DT),Logistic Regression(LR),and Naive Bayes(NB).The accuracy of three Feature Extraction(FE)algorithms is detected;Principal Component Analysis(PCA),Auto-encoder(AE),and Linear Discriminant Analysis(LDA),are evaluated using three benchmark datasets:UNSW-NB15,ToN-IoT and CSE-CIC-IDS2018.Although PCA and AE algorithms have been widely used,the determination of their optimal number of extracted dimensions has been overlooked.The results indicate that no clear FE method or ML model can achieve the best scores for all datasets.The optimal number of extracted dimensions has been identified for each dataset,and LDA degrades the performance of the ML models on two datasets.The variance is used to analyse the extracted dimensions of LDA and PCA.Finally,this paper concludes that the choice of datasets significantly alters the performance of the applied techniques.We believe that a universal(benchmark)feature set is needed to facilitate further advancement and progress of research in this field. 展开更多
关键词 Feature extraction Machine learning Network intrusion detection system IOT
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Experimental investigation on coal pore-fracture variation and fractal characteristics synergistically affected by solvents for improving clean gas extraction 被引量:1
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作者 Feilin Han Sheng Xue +3 位作者 Chunshan Zheng Zhongwei Chen Guofu Li Bingyou Jiang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期413-425,共13页
Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal... Chemical solvents instead of pure water being as hydraulic fracturing fluid could effectively increase permeability and improve clean methane extraction efficiency.However,pore-fracture variation features of lean coal synergistically affected by solvents have not been fully understood.Ultrasonic testing,nuclear magnetic resonance analysis,liquid phase mass spectrometry was adopted to comprehensively analyze pore-fracture change characteristics of lean coal treated by combined solvent(NMP and CS_(2)).Meanwhile,quantitative characterization of above changing properties was conducted using geometric fractal theory.Relationship model between permeability,fractal dimension and porosity were established.Results indicate that the end face fractures of coal are well developed after CS2and combined solvent treatments,of which,end face box-counting fractal dimensions range from 1.1227 to 1.4767.Maximum decreases in ultrasonic longitudinal wave velocity of coal affected by NMP,CS_(2)and combined solvent are 2.700%,20.521%,22.454%,respectively.Solvent treatments could lead to increasing amount of both mesopores and macropores.Decrease ratio of fractal dimension Dsis 0.259%–2.159%,while permeability increases ratio of NMR ranges from 0.1904 to 6.4486.Meanwhile,combined solvent could dissolve coal polar and non-polar small molecules and expand flow space.Results could provide reference for solvent selection and parameter optimization of permeability-enhancement technology. 展开更多
关键词 Clean gas extraction Chemical solvent Experimental investigation Fractal characteristics Pore fracture
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Applications of SMILE-extracted lenticules in ophthalmology 被引量:1
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作者 Hossein Aghamollaei Hassan Hashemi +3 位作者 Mahsa Fallahtafti Seyed-Hashem Daryabari Mehdi Khabazkhoob Khosrow Jadidi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期173-187,共15页
AIM:To review recent innovations,challenges,and applications of small incision lenticule extraction(SMILE)extracted lenticule for treating ocular disorders.METHODS:A literature review was performed in the PubMed datab... AIM:To review recent innovations,challenges,and applications of small incision lenticule extraction(SMILE)extracted lenticule for treating ocular disorders.METHODS:A literature review was performed in the PubMed database,which was last updated on 30 December 2021.There was no limit regarding language.The authors evaluated the reference lists of the collected papers to find any relevant research.RESULTS:Due to the simplicity and accuracy of modern femtosecond lasers and the extensive development of SMILE surgery,many healthy human corneal stromal lenticules were extracted during surgery,motivating some professionals to investigate the SMILE lenticule reusability in different ocular disorders.In addition,new approaches had been developed to preserve,modify,and bioengineer the corneal stroma,leading to the optimal use of discarded byproducts such as lenticules from SMILE surgery.The lenticules can be effectively re-implanted into the autologous or allogenic corneas of human subjects to treat refractive errors,corneal ectasia,and corneal perforation and serve as a patch graft for glaucoma drainage devices with better cosmetic outcomes.CONCLUSION:SMILE-extracted lenticules could be a viable alternative to human donor corneal tissue. 展开更多
关键词 small incision lenticule extraction corneal lenticule implantation KERATOCONUS corneal perforation femtosecond laser stromal keratophakia
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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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Economic and entropy production evaluation of extractive distillation and solvent-assisted pressure-swing distillation by multi-objective optimization
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作者 Yao Wang Qing Ye +2 位作者 Jinlong Li Qingqing Rui Azhi Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期246-259,共14页
Extractive distillation(ED)and solvent-assisted pressure-swing distillation(SA-PSD)are both special distillation processes that perform good at separating pressure-insensitive azeotropes.However,few reported studies h... Extractive distillation(ED)and solvent-assisted pressure-swing distillation(SA-PSD)are both special distillation processes that perform good at separating pressure-insensitive azeotropes.However,few reported studies have compared the performance of the two processes.In this paper,ED processes with N-methylpyrrolidone(NMP)and dimethlac-etamide(DMCA)as entrainer,SA-PSD process with isopropyl-alcohol(IPA)as solvent and SA-PSD process with partial heat integration(PHI-PSD)are proposed to achieve high purity separation of a mixture of cyclohexane/2-butanol system.The optimal operating conditions of the processes are obtained after optimizing with NSGA-Ⅱ algorithm when total annual cost(TAC)and the entropy production of process are set as objectives.The optimal results show that the optimal PHI-PSD process has lower TAC by 28.7% and the lower entropy production by 39.5% than the optimal SA-PSD process while the ED process with NMP as entrainer has lower TAC by 50.9% and the lower entropy production by 56.1% than the optimal SA-PSD process.The optimal results show that the ED process with NMP as entrainer has the best economic and thermodynamic efficiency among the four proposed processes in this paper. 展开更多
关键词 extractive distillation Solvent-assisted pressure-swing distillation Entropy production NSGA-Ⅱalgorithm Computer simulation
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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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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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Antimicrobial Activities of Plant Extracts against Streptococcus pneumoniae Isolated from Pediatric Patients at Federal Teaching Hospital Abakaliki, Ebonyi State
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作者 Euslar Nnenna Onu Donatus Chukwuma Ilang +5 位作者 Cornelius Ituma Azi Theophilus Onwe Eze Chinedu Obasi Akpa Oluwatoyin Oluwatosin Kelechi-Mathew Okechukwu Emmanuel Ogbonna Samuel Eleojo Agada 《American Journal of Plant Sciences》 CAS 2024年第10期847-857,共11页
Antibiotic-resistant genes have become a threat to synthetic or conventional medications and because of this much work has been done on using plants and plants part to treat disease caused by bacteria, Herbal medicine... Antibiotic-resistant genes have become a threat to synthetic or conventional medications and because of this much work has been done on using plants and plants part to treat disease caused by bacteria, Herbal medicine has served as effective treatment against various diseases caused by pathogenic bacteria and multi drug-resistant strains of bacteria which made it advantageous over synthetic medications. This study aimed to reveal the sensitivity of Streptococcus pneumoniae from clinical isolate and perform antibacterial assay on the organism using plants leaf extracts of Ocimum gratissimum, Sida acuta, Newbouldia laevia and Mimosa pudica. Gram staining and various biochemical test were used for the identification of Streptococcus pneumoniae. The plants leaves were aseptically washed, dried and ground into fine powder and diluted in varying concentration and agar well diffusion method was used to test for the antimicrobial properties of this plants on Streptococcus pneumoniae at various concentrations as follows 0.1 g/ml, 0.4 g/ml, 0.6 g/ml and 1 g/ml. The plants extract of Ocimum gratissimum showed a greater antibacterial effects on Streptococcus pneumoniae in high concentration more than other plant extracts while Sida acuta and Newbouldia laevia plant extract showed weak antibacterial properties to the organism. This proves that Ocimum gratissimum and Mimosa pudica leaves have good and strong antibacterial properties against Streptococcus pneumoniae than Sida acuta and Newbouldia laevia and can be used as antibacterial agent at adequate concentrations. 展开更多
关键词 CONVENTIONAL HERBAL ANTIBACTERIAL extractS CONCENTRATIONS
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Influence of the Extraction Process on the Characteristics of Romanian Mountain Walnut Oil
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作者 Anne-Gaëlle Gambert Sabina Niţu +6 位作者 Andra Tămaș Maria Laura Fanani Justine Dupré Clara Delepine Ludovic Chaveriat Patrick Martin Lucian Rusnac 《American Journal of Plant Sciences》 CAS 2024年第10期940-967,共28页
The objective of this work is to extract walnut oil using various processes in order to compare the influence on the nature of the components extracted, and thus identify the areas of potential use. We carried out the... The objective of this work is to extract walnut oil using various processes in order to compare the influence on the nature of the components extracted, and thus identify the areas of potential use. We carried out the extractions by mechanical process, thanks to a press in reduced model provided with a worm. We obtained cold extracted oil whose characteristics slightly diverge from extra virgin oil found in shops in Romania, but its composition is similar. We were also able to extract by chemical process using two methods, Folch and Soxhlet. Commercially available table walnut oils are only cold extracted to avoid the presence of solvents. Those are difficult to remove and strongly oxidize the oil. Currently, consumers appreciate walnut oil for its taste and nutritional qualities. In nutrition, this oil is put forward for its composition rich in polyunsaturated fatty acids, which are needed for human body. Food supplements made from walnut oil are available today. For the moment, this is the only use of walnut oil. Indeed, there are some studies on other fields of application, but they remain in the field of research and nothing has yet been commercialized. In this present study, we compared the chemical and physical properties of cold-extracted oil with the solvent extraction of walnut kernel originating from the mountain region of Rumania. The cold extracted oil has a high content of polyunsaturated fatty acids (63%) and monounsaturated fatty acids (30%), a very low level of saturated fatty acid (7%) and no content of linolenic acid. The Soxhlet and Folch methods produced slightly different oils with increased amounts of minor components, which changes their characteristic. Even when solvent-extracted oils do not meet the standard criteria imposed by the Codex Alimentarius, they offer a possible use in the fields of food, cosmetics industries and biomedicine. 展开更多
关键词 Walnut Oil extractION COMPOSITION Romanian Mountain
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Development of a Simple Extraction Method for Tetracycline Analogues from Bovine Milk
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作者 Oscar Cordova Thien Le +4 位作者 Christopher Lambert Devin Brodie Stephany Ramirez Francis Sandoval Karno Ng 《Advances in Biological Chemistry》 CAS 2024年第4期111-120,共10页
Tetracycline and analogues are among the most used antibiotics in the dairy industry. Besides the therapeutic uses, tetracyclines are often incorporated into livestock feed as growth promoters. A considerable amount o... Tetracycline and analogues are among the most used antibiotics in the dairy industry. Besides the therapeutic uses, tetracyclines are often incorporated into livestock feed as growth promoters. A considerable amount of antibiotics is released unaltered through milk from dairy animals. The presence of antibiotic residues in milk and their subsequent consumption can lead to potential health impacts, including cancer, hypersensitivity reactions, and the development of antibiotic resistance. Thus, it is important to monitor residual levels of tetracyclines in milk. The purpose of this study is to develop a quick and simple method for simultaneously extracting five tetracycline analogues from bovine milk. Specifically, five tetracycline analogues: Chlortetracycline (CTC), demeclocycline (DEM), doxycycline (DC), minocycline (MC), and tetracycline (TC) were simultaneously extracted from milk using trifluoroacetic acid. Subsequently, the extracted analogues were separated by reverse-phase high-performance liquid chromatography (RP-HPLC) and detected at 355 nm using UV/Vis. Calibration curves for all five tetracycline analogues show excellent linearity (r2 value > 0.99). Percent recovery for MC, TC, DEM, CTC, and DC were: 31.88%, 96.91%, 151.29, 99.20%, and 85.58% respectively. The developed extraction method has good precision (RSD < 9.9% for 4 of the 5 analogues). The developed method with minimal sample preparation and pretreatment has the potential to serve as an initial screening test. 展开更多
关键词 ANTIBIOTICS TETRACYCLINES extraction MILK HPLC
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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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Effect of Rosmarinus officinalis and Origanum majorana extracts on stability of sunflower oil during storage and repeated heating
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作者 Ali Sahunie 《Oil Crop Science》 CSCD 2024年第1期29-37,共9页
Both rosemary(Rosmarinus officinalis)and marjoram(Origanum majorana)are abundant in phenolic compounds,exhibiting exceptional antioxidant activity.This study aims to assess the impact of rosemary and marjoram extracts... Both rosemary(Rosmarinus officinalis)and marjoram(Origanum majorana)are abundant in phenolic compounds,exhibiting exceptional antioxidant activity.This study aims to assess the impact of rosemary and marjoram extracts on the stability of sunflower oil during storage and repeated heating.Sunflower oil supplemented with herbal extracts or butylated hydroxytoluene(BHA)at a concentration of 200 ppm was stored for six months under light and dark conditions at room temperature.Peroxide value(PV),p-anisidine value(An-V),and total oxidation(TOTOX)value were measured to monitor lipid oxidation progression.A significant difference(P<0.05)was observed between light and dark storage for all studied samples regarding oxidation parameters.The ethanolic extract of rosemary exhibited higher antioxidant activity compared to BHA and other extracts.Furthermore,sunflower oil supplemented with the ethanolic extract of rosemary underwent weekly treatment at 100℃for 30 min over four consecutive weeks.Although all oxidation indicators increased during repeated heating,the addition of rosemary and marjoram extracts as well as BHA significantly reduced these indicators.These findings demonstrate that both rosemary extracts and marjoram extracts can serve as natural antioxidants in edible oils. 展开更多
关键词 Phenolic compounds BHA Marjoram extract Rosemary extract Sunflower oil
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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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