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Preferentially selective extraction of lithium from spent LiCoO_(2)cathodes by medium-temperature carbon reduction roasting 被引量:2
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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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Synergistic solvent extraction of boric acid by trioctylamine and 2-hydroxydodecanoic acid
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作者 Zhuojun Jiang Yufeng Liang +5 位作者 Shuyao Xiong Guo Li Qian Zhang Benzheng Xia Liangrong Yang Zheng Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期117-126,共10页
A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of li... A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of ligands might impact H_(3)BO_(3) extraction,boron isotope separation,and solvent loss,which has not been thoroughly investigated.This study initially evaluated the influence of ligand's type,pKa,and substituents on H_(3)BO_(3) extraction efficiency,as well as the impact of the B_((4))-O structure(boron is bound to four oxygen atoms)in the organic phase on isotope separation efficiency.Subsequently,by synthesizing the highly hydrophobic 2-hydroxydodecanoic acid(HYA),the extraction performance and mechanism of the TOA/HYA system were investigated.The findings highlight the superior extraction efficiency when employing di-phenolic hydroxyl,phenolic hydroxyl + carbinol hydroxyl,and alcoholic hydroxyl + carboxyl ligands compared to phenolic hydroxyl + carboxyl,phenolic hydroxyl + ethanol hydroxyl,diol hydroxyl,and dicarboxylic ligands.The organic phase anion complex,exclusively comprising the B_((4))-O structure,enhances isotope separation effectiveness.The TOA/HYA system achieves an 80%single-stage extraction efficiency for H_(3)BO_(3).H_(3)BO_(3) and HYA are extracted into the organic phase at a ratio of 1:2,with the anion complex solely containing the B_((4))-O structure.This study paves the way for the construction of novel boric acid extraction and boron isotope separation systems. 展开更多
关键词 Boric acid 2-Hydroxydodecanoic acid Synergistic extraction Coordination mechanism Boron isotope separation
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Kinetics of Reactive Extraction of Nd from Nd2O3 with TBP-HNO3 Complex in Supercritical Carbon Dioxide 被引量:3
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作者 朱礼洋 段五华 +1 位作者 徐景明 朱永 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期214-218,共5页
The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generat... The process based on supercritical fluid extraction for reprocessing of the spent nuclear fuel has some remarkable advantages over the plutonium-uranium extraction(PUREX) process.Especially,it can minimize the generation of secondary waste.Dynamic reactive extraction of neodymium oxide(Nd2O3) in supercritical carbon dioxide(SC-CO2) containing tri-n-butyl phosphate-nitric acid(TBP-HNO3) complex was investigated.Temperature showed a positive effect on the extraction efficiency,while pressure showed a negative effect when the unsaturated TBP-HNO3 complex was employed for the dynamic reactive extraction of Nd2O3 in SC-CO2.Both temperature and pressure effects indicated that the kinetic process of the reactive extraction was controlled by the chemical reaction.A kinetic model was proposed to describe the extraction process. 展开更多
关键词 supercritical carbon dioxide KINETIcs reactive extraction TBP-HNO3 complex ND2O3
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Detection of Tetracycline Antibiotics in Water by Dispersive Micro-solid Phase Extraction using Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]Magnetic Composite Combined with Liquid Chromatography-Tandem Mass Spectrometry 被引量:2
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作者 Yan-ni Li Yan-yun Hu +2 位作者 Lei Ding Dian-bing Zhou Wen-jun Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第2期238-248,I0002,共12页
Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analys... Residues of tetracycline antibiotics(TCs) in environments may be harmful to human.Due to their high polarities,it is extremely challenging to efficiently enrich TCs with low concentrations in natural waters for analysis.In this work,a magnetic metal-organic framework Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]was synthesized and applied as a dispersive micro-solid phase extraction adsorbent for TCs enrichment.Effects of dispersive micro-solid phase extraction conditions including extraction time,solution p H,and elution solvent on the extraction efficiencies of TCs were investigated.Results show that TCs could be enriched efficiently by Fe_(3)O_(4)@[Cu_(3)(btc)_(2)],and electrostatic interaction between TCs and Fe_(3)O_(4)@[Cu_(3)(btc)_(2)]dominated this process.Combined with liquid chromatography-tandem mass spectrometry,four TCs residues (oxytetracycline,tetracycline,chlortetracycline,and doxycycline) in natural waters were determined.The detection limits (LOD,S/N=3) of the four antibiotics were 0.01-0.02μg/L,and the limits of quantitation (LOQ,S/N=10)were 0.04-0.07μg/L.The recoveries obtained from river water and aquaculture water spiked with three TCs concentration levels ranged from 70.3%to 96.5%with relative standard deviations of 3.8%-12.8%.Results indicate that the magnetic metal-organic framework based dispersive micro-solid phase extraction is simple,rapid and high-loading for antibiotics enrichment from water,which further expand the practical application of metal-organic frameworks in sample pretreatment for environmental pollutant analysis. 展开更多
关键词 Fe_(3)O_(4)@[Cu_(3)(btc)_(2)] Metal-organic frameworks Dispersive micro-solid phase extraction Tetracycline
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Thermodynamics and mechanism of vanadium(IV) extraction from sulphate medium with D2EHPA,EHEHPA and CYANEX 272 in kerosene 被引量:15
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作者 李兴彬 魏昶 +4 位作者 吴钧 李存兄 李旻廷 邓志敢 徐红胜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期461-466,共6页
Extraction of vanadium(IV) from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium... Extraction of vanadium(IV) from sulphate acid solution was studied using organophosphorous-based extractants D2EHPA, EHEHPA and CYANEX 272 in kerosene. The different parameters affecting the extraction of vanadium(IV) under equilibrium conditions were separately investigated to elucidate the stoichiometry of the extracted species. The distribution ratio of vanadium increased with increasing equilibrium pH of the aqueous phase, concentration of the extractants and temperature. D2EHPA was found to be a stronger extractant, having greater pH functionality than EHEHPA and CYANEX 272. Extraction of vanadium(IV) by these organophosphorous-based extractants involved cation exchange mechanism, and the extracted species appear to be VOR2(HR)2 in the low equilibrium pH and VOR2 in the higher equilibrium pH, where HR refers to the three acidic extractants. 展开更多
关键词 VANADIUM solvent extraction D2EHPA EHEHPA CYANEX 272
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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO_2 extraction on Chinese fir 被引量:9
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,共5页
Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of se... Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2. 展开更多
关键词 chinese fir autointoxication supercritical CO_2 extraction BIOASSAY SEEDGERMINATION
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Surface passivation and hole extraction:Bifunctional interfacial engineering toward high-performance all-inorganic CsPbIBr2 perovskite solar cells with efficiency exceeding 12%
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作者 Qi Liu Junming Qiu +9 位作者 Xianchang Yan Yuemeng Fei Yue Qiang Qingyan Chang Yi Wei Xiaoliang Zhang Wenming Tian Shengye Jin Ze Yu Licheng Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第11期387-393,I0011,共8页
All-inorganic CsPbIBr2perovskite solar cells(PSCs)have attracted considerable research attention in recent years due to their excellent thermal stability.However,their power conversion efficiencies(PCEs)are relatively... All-inorganic CsPbIBr2perovskite solar cells(PSCs)have attracted considerable research attention in recent years due to their excellent thermal stability.However,their power conversion efficiencies(PCEs)are relatively low and still far below the theoretical limit.Here,we report the use of an organic dye molecule(namely VG1-C8)as a bifunctional interlayer between perovskite and the hole-transport layer in CsPbIBr2PSCs.Combined experimental and theoretical calculation results disclose that the multiple Lewis base sites in VG1-C8 can effectively passivate the trap states on the perovskite films.Meanwhile,theπ-conjugated dye molecule significantly accelerates the hole extraction from the perovskite absorber as evidenced by the photoluminescence analysis.Consequently,the VG1-C8 treatment simultaneously boosts the photovoltage and photocurrent density values from 1.26 V and 10.80 mA cm^(-2) to 1.31 V and 12.44 m A cm^(-2),respectively.This leads to a significant enhancement of PCE from 9.20%to12.10%under one sun irradiation(AM 1.5G).To our knowledge,this is the record efficiency reported so far for CsPbIBr_(2) PSCs.Thus,the present work demonstrates an effective interfacial passivation strategy for the development of highly efficient PSCs. 展开更多
关键词 All-inorganic perovskite solar cells csPbIBr2 Defect passivation Hole extraction High efficiency
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KINETICS OF ALUMINUM EXTRACTION WITH DI—2-ETHYLHEXYL PHOSPHORIC ACID
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作者 Ma Yun Zhu Tun 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1992年第4期14-20,共7页
The kinetics of solvent.extraction of aluminum with di-2-ethylhexyl phosphoric acid(DEHPA)in n-heptane have been studied in a constant interfacial area cell.A HC1-KHC8H404(potassium biphthalate.KHL)buffer solution was... The kinetics of solvent.extraction of aluminum with di-2-ethylhexyl phosphoric acid(DEHPA)in n-heptane have been studied in a constant interfacial area cell.A HC1-KHC8H404(potassium biphthalate.KHL)buffer solution was used to maintain a constant pH during extraction.The effects of the concentration of aluminum,pH,the concentration of the extractant,the interfacial area and the temperature on the extraction rate were investigated.A method has been invented to determine amont of the extracted aluminum in the organic phase with 8-hydroxyquinoline.Based on calculation of the coordination states of the aluminum ions and their contribution to the reaction rate,a raaction mechanism which includes two main reaction paths,has been proposed to describe the process.One path starts from Al(H_(2)O)6^(+).and the other starts from Al(H_(2)O)6^(+).The reaction could take place both in the aqueous phase and at the interface.The main reaction region could be changed as the conditions of extraction were changed.When[HA]<0.03 mol/L the process was controlled by the interfacial reaction,and when[HA]>0.03 mol/L it was shifted to a homogeneous aqueous solution reaction. 展开更多
关键词 ALUMINUM solvent extraction kinetics constant interfacial area cell di-2-ethylliexyl phosphoric
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Trace amount of chromium(III) in waste water measured by extraction spectrophometry in H2CrO6-n-CsH11OH system
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作者 ZHANG Guo-fu YE He-lin +1 位作者 LIANG Peng LIU Ling-ling 《Journal of Chemistry and Chemical Engineering》 2008年第6期49-51,共3页
A novel, simple, rapid, economic and hypersensitive method of measuring Cr3+ is described in this paper. Cr3+ could be oxidated to H2CrO6, which is extracted by n-C5H11OH, so a trace amount of chromium is measured d... A novel, simple, rapid, economic and hypersensitive method of measuring Cr3+ is described in this paper. Cr3+ could be oxidated to H2CrO6, which is extracted by n-C5H11OH, so a trace amount of chromium is measured directly by spectrometers, Sandra sensitivity is S=6.40×10^-3 ug.cm-2. 展开更多
关键词 chromium(III) H2O2 n-pentanol extraction SPECTROPHOTOMETERS
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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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Effect of Allelochemicals of Chinese-fir root extracted by supercritical CO2 extraction on Chinese fir 被引量:5
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作者 林思祖 曹光球 +1 位作者 杜玲 王爱萍 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期122-126,185-186,共页
Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of s... Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of seed germination. The results showed that as to the available rate of allelochemicals, the pressure and temperature of extraction were the most important factors. The allelochemicals of Chinese-fir root extracted by pure CO2 and ethanol mixed with CO2 have different allelopathic activities to seed germination, and the allelochemicals extracted by ethanol mixed with CO2 had stronger inhibitory effects on seed germination than that extracted by pure CO2. 展开更多
关键词 Chinese fir Autointoxication Supercritical CO2 extraction BIOASSAY Seed germination
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Joint Biomedical Entity and Relation Extraction Based on Multi-Granularity Convolutional Tokens Pairs of Labeling
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作者 Zhaojie Sun Linlin Xing +2 位作者 Longbo Zhang Hongzhen Cai Maozu Guo 《Computers, Materials & Continua》 SCIE EI 2024年第9期4325-4340,共16页
Extracting valuable information frombiomedical texts is one of the current research hotspots of concern to a wide range of scholars.The biomedical corpus contains numerous complex long sentences and overlapping relati... Extracting valuable information frombiomedical texts is one of the current research hotspots of concern to a wide range of scholars.The biomedical corpus contains numerous complex long sentences and overlapping relational triples,making most generalized domain joint modeling methods difficult to apply effectively in this field.For a complex semantic environment in biomedical texts,in this paper,we propose a novel perspective to perform joint entity and relation extraction;existing studies divide the relation triples into several steps or modules.However,the three elements in the relation triples are interdependent and inseparable,so we regard joint extraction as a tripartite classification problem.At the same time,fromthe perspective of triple classification,we design amulti-granularity 2D convolution to refine the word pair table and better utilize the dependencies between biomedical word pairs.Finally,we use a biaffine predictor to assist in predicting the labels of word pairs for relation extraction.Our model(MCTPL)Multi-granularity Convolutional Tokens Pairs of Labeling better utilizes the elements of triples and improves the ability to extract overlapping triples compared to previous approaches.Finally,we evaluated our model on two publicly accessible datasets.The experimental results show that our model’s ability to extract relation triples on the CPI dataset improves the F1 score by 2.34%compared to the current optimal model.On the DDI dataset,the F1 value improves the F1 value by 1.68%compared to the current optimal model.Our model achieved state-of-the-art performance compared to other baseline models in biomedical text entity relation extraction. 展开更多
关键词 Deep learning BIOMEDICAL joint extraction triple classification multi-granularity 2D convolution
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Parameter Extraction for 2-π Equivalent Circuit Model of RF CMOS Spiral Inductors 被引量:1
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作者 高巍 余志平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第4期667-673,共7页
A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experiment... A novel parameter extraction method with rational functions is presented for the 2-πequivalent circuit model of RF CMOS spiral inductors. The final S-parameters simulated by the circuit model closely match experimental data. The extraction strategy is straightforward and can be easily implemented as a CAD tool to model spiral inductors. The resulting circuit models will be very useful for RF circuit designers. 展开更多
关键词 2-π compact model parameters extraction RF CMOS spiral inductors
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Synergistic extraction of rare earth by mixtures of 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester and di-(2-ethylhexyl) phosphoric acid from sulfuric acid medium 被引量:9
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作者 黄小卫 李建宁 +3 位作者 龙志奇 张永奇 薛向欣 朱兆武 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期410-413,共4页
The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric a... The extraction of Nd^3+ and Sm^3+, including the extraction and stripping capability as well as the separation effect of Nd^3+ or Sm^3+, from a sulfuric acid medium, by mixtures of di-(2-ethylhexyl) phosphoric acid (HDEHP, H2A2(0)) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (HEH/EHP, H2L2(0)) were studied. The distribution ratios and synergistic coefficients of Nd^3+ and Sm^3+ in different acidities were also determined. A synergistic extractive effect was found when HDEHP and HEH/EHP were used as mixed extractants for Sm^3+ or Nd^3+. The chemical compositions of the extracted complex were determined as Nd.(HA2)2-HL2 and Sm.(HA2)2-HL2. The extraction equilibrium constants, enthalpy change, and entropy change of the extraction reaction were also determined. 展开更多
关键词 di-2-ethylhexyl) phosphoric acid 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester synergistic extraction mechanism Sm^3+ Nd^3+ rare earths
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The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket 被引量:10
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作者 Chang Liu Zhe Wu Hong-chen Sun 《International Journal of Oral Science》 SCIE CAS CSCD 2009年第2期90-98,共9页
Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (... Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. 展开更多
关键词 bone morphogenetic protein-2 (BMP-2 in situ hybridization SIMVASTATIN tooth extraction socket transforming growth factor-β1 (TGF-β1) vascular endothelial growth factor (VEGF)
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Salting-out Extraction of 2,3-Butanediol from Jerusalem artichoke-based Fermentation Broth 被引量:6
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作者 DAI Jianying ZHANG Yuanli XIU Zhilong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第4期682-686,共5页
The removal of solid impurities and separation of target products from a fermentation broth is becoming more tedious with the utilization of lignocelluloses as source of substrate.2,3-Butanediol,an important chemical ... The removal of solid impurities and separation of target products from a fermentation broth is becoming more tedious with the utilization of lignocelluloses as source of substrate.2,3-Butanediol,an important chemical used widely is also a main product of sugar-based fermentation carried out by Klebsiella pneumoniae.In this study,we investigated the use of salting-out extraction(SOE) that employed a K2HPO4/ethanol system consisting of 21% ethanol and 17% K2HPO4(mass fraction) to separate 2,3-butanediol from the viscous Jerusalem artichoke-based fermentation broth.After SOE,about 98% of solid matters was removed,and the viscosity decreased from 72.5 mPa s in the original fermentation broth to 4.4 mPa s in the top phase.The partition coefficient and yield of 2,3-butanediol reached 13.4 and 99%,respectively,and 89% of soluble proteins was removed from the broth.The results showed that SOE is an efficient way for isolating 2,3-BD from a highly viscous fermentation broth by removing much of the solid matters within the broth. 展开更多
关键词 2 3-butanediol Jerusalem artichoke salting-out extraction VISCOSITY
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GC/MS Analysis of Fractional Extraction of Fusain from Tongting Bituminous Coal in CS_2 被引量:10
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作者 QIN Zhi-hong JIANG Chun SUN Hao ZONG Zhi-min JIANG Bing WEI Xian-yong 《Journal of China University of Mining and Technology》 EI 2006年第1期8-12,共5页
Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FT... Fusain from Tongting (Huaibei, Anhui Province) bituminous (FTTB) coal was fractionally extracted using Soxhlet extractor with CS2. Then the extracts were analyzed with GC/MS. Comparison of experimental data between FTTB coal and clarain from Tongting bituminous (CTTB) coal was carried out. The results show that the kinds of small molecule components detected by GC/MS of FTTB are less than those of CTTB. Long-chain alkanes exist mostly in the extracts of fusain. Macromolecular networks are predominant in the FTTB coal mainly composed of inertinite in the coal petrography. The size of micropores in the FTTB coal is relatively small, and the development of micropores is relatively low. Thus the content of aromatic compounds with affinity for micropores is relative low in FTTB, while the content of long-chain alkanes with affinity for macromolecule networks is relatively high. Sub-components in exinite determine the distribution of long-chain alkanes extracted in the last stage. Odd-numbered carbon distribution appears when resin is most in exinite, while high carbon alkane distribution appears when exinite is dominant in cutinite. Small aromatic molecules are firstly packed in micropores, and exist in a free state after micropores are saturated. 展开更多
关键词 COAL fusain extraction fractional sample cs2 GC/MS
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Comparison of Constituents and Insecticidal Activities of Essential Oil from Artemisia lavandulaefolia by Steam Distillation and Supercritical-CO_2 Fluid Extraction 被引量:8
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作者 YUAN Hai-bin SHANG Li-na +1 位作者 WEI Chun-yan REN Bing-zhong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第6期888-892,共5页
Essential oil was extracted from Artemisia lavandulaefolia DC.by steam distillation(SD) and supercritical-CO2 fluid extraction(SFE),respectively.The constituents of the essentil oils extracted with those two metho... Essential oil was extracted from Artemisia lavandulaefolia DC.by steam distillation(SD) and supercritical-CO2 fluid extraction(SFE),respectively.The constituents of the essentil oils extracted with those two methods were analyzed by gas chromatography-mass spectrometry(GC-MS) and insecticidal activities of the essential oils were evaluated,then the results were compared to assess their biological activity.Thirty-one compounds were identified in the essential oil extracted by SD,and its main components were eucalyptol,α,α,4-trimethyl-3-cyclohexene-1-methanol and so on.Twenty-two compounds were identified for the essential oil extracted by SFE,and its main components were cyclodecene,n-hexadecanoic acid and so on.Six chemical compositions were all contained in the essential oils extracted by the two methods,i.e.,eucalyptol,α,α,4-trimethyl-3-cyclohexene-1-methanol,caryophyllene,[3aS-(3aα,3bβ,4β,7α,7aS)]-octahydro-7-methyl-3-methylene-4-(1-methylethyl)-1H-cyclopenta[1,3]cyclopropa-[1,2]benzene,nerolidol and(-)-Spathulenol.The fumigation toxicity of the essential oil obtained by means of SD to the adults of Sitophilus zeamais is significantly higher than that of the essential oil by means of SFE.The contact toxicity of the essential oil obtained by means of SFE to the adults of S.zeamais is higher than that of the essential oil obtained by means of SD,but the difference is not significant. 展开更多
关键词 Artemisia lavandulaefolia DC. Essential oil Supercritical-CO2 fluid extraction Steam distillation GC-MS Insecticidal activity
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Liquid-liquid Extraction System Based on Non-ionic Surfactant-salt-H_2O and Mechanism of Drug Extraction 被引量:3
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作者 LeiLI FengLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期349-350,共2页
Extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydro- chloride (PCN) in the system described in the title was studied. Research shows that the extraction efficiency of CPZ can amount to 96% by... Extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydro- chloride (PCN) in the system described in the title was studied. Research shows that the extraction efficiency of CPZ can amount to 96% by twice extraction, while that of PCN is 77%. This system produces the distribution coefficients (KD) of 12.3 and 2.6 respectively for CPZ and PCN. Extraction mechanism is deduced according to ultraviolet and molecular fluorescence spectra variation of the drugs in the system studied. 展开更多
关键词 Non-ionic surfactant-salt-H2O extraction system polyethylene glycol-1000 chlor- promazine hydrochloride procaine hydrochloride mechanism of extraction.
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Dynamic analysis of heat extraction rate by supercritical carbon dioxide in fractured rock mass based on a thermal-hydraulic-mechanics coupled model 被引量:4
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作者 Chunguang Wang Xingkai Shi +7 位作者 Wei Zhang Derek Elsworth Guanglei Cui Shuqing Liu Hongxu Wang Weiqiang Song Songtao Hu Peng Zheng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第2期225-236,共12页
Heat production from geothermal reservoirs is a typical heat transfer process involving a cold working fluid contacting a hot rock formation.Compared to the thermal-physical characteristics of water,supercritical CO_(... Heat production from geothermal reservoirs is a typical heat transfer process involving a cold working fluid contacting a hot rock formation.Compared to the thermal-physical characteristics of water,supercritical CO_(2)(scCO_(2))has a higher heat storage capacity over a wide temperature-pressure range and may be favored as a heat transfer fluid.Singularly characteristic of scCO_(2)-based heat extraction is that the hydraulic-thermal properties of the scCO_(2) vary dramatically and dynamically with the spatial pressure gradient during unsteady-state flow along fracture.This highly nonlinear behavior presents a challenge in the accurate estimation of heat extraction efficiency in scCO_(2)-based EGS.In this paper,a thermal-h ydraulic-mechanical(THM)coupled model is developed by considering deformation of the fractured reservoir,non-Darcy flow and the varying thermal-physical properties of scCO_(2).The proposed model is validated by matching the modeling temperature distribution with published data.The results show that during continuous injection of scCO_(2),the fracture first widens and then narrows,ultimately reopening over the long term.The sequential fracture deformation behaviors are in response to the combined impacts of mechanical compression and thermally-induced deformation.By controlling the injection parameters of the scCO_(2),it is found that the heat extraction rate is positively correlated to its pore pressure or mass flow rate.The heat extraction rate can be significantly enhanced,when the inlet temperature of scCO_(2) is below its critical temperature.As a result,the heat increment recovered per unit mass of scCO_(2) decreases as the hot rock is gradually cooled.Meanwhile,the heat increment recovered per unit mass of scCO_(2) decreases by increasing the inlet temperature of scCO_(2) or its mass flow rate,but increases as the outlet pressure rises.Furthermore,multi-linear regression indicates that controlling the inlet temperature of the scCO_(2) can significantly improve the thermodynamic efficiency of heat extraction. 展开更多
关键词 Supercritical CO_(2) Heat extraction Hot rock Geothermal energy Fracture-matrix interaction
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