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Autotoxicity of Water Extracts and Decomposition Liquids of Tumorous Stem Mustard(Brassica juncea var.tumida Tsen et Lee) Residues on Seed Germination and Seedling Growth of Tumorous Stem Mustard
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作者 Bo JIANG Xianrong ZHOU +4 位作者 Jin SHANG Jianhua WANG Changman LI Huichao WANG Miao YANG 《Agricultural Science & Technology》 CAS 2016年第7期1519-1524,1529,共7页
[Objective] This study aimed to explore whether there is autotoxicity in tumorous stem mustard through studying the allelopathic effects of water extracts and decomposition liquids of tumorous stem mustard residues on... [Objective] This study aimed to explore whether there is autotoxicity in tumorous stem mustard through studying the allelopathic effects of water extracts and decomposition liquids of tumorous stem mustard residues on seed germination and seedling growth of tumorous stem mustard.[Method] With Fuza No.2 as the experimental material,the effects of different concentrations of leaf extract,root extract,7-d decomposition liquid,15-d decomposition liquid of tumorous stem mustard on seed germination and seedling growth of tumorous stem mustard were investigated.[Result] Compared with those in the control,the four kinds of 100% treatment solutions all significantly reduced the seed germination rate,seed germination vigor,root length,plant height and fresh weight of tumorous stem mustard(P<0.05),and significantly increased the malondialdehyde(MDA) content,catalase(CAT) activity,peroxidase(POD) activity and superoxide dismutase(SOD) activity of young seedlings of tumorous stem mustard;the allelopathic effects of the four kinds of water extracts and decomposition liquids on seed germination and root length of tumorous stem mustard were weakened with the decreased concentration;for the four kinds of water extracts and decomposition liquids,low-concentration treatment solutions promoted the increase of plant height and fresh weight,while high-concentration treatment solutions inhibited the increase of plant height and fresh weight of young seedlings of tumorous stem mustard;the allelopathic effect of leaf extract on seed germination of tumorous stem mustard was stronger than those of root extract and decomposition liquids,the allelopathic effects of decomposition liquids on seedling growth of tumorous stem mustard were stronger than those of water extracts,the inhibitory effect of leaf extract on seed germination and seedling growth of tumorous stem mustard were stronger than that of root extract,and the inhibitory effect of 15-d decomposition liquid on seed germination and seedling growth of tumorous stem mustard was stronger than that of 7-d decomposition liquid.[Conclusion] The water extracts and decomposition liquids of tumorous stem mustard residues had certain autotoxicity on seed germination and seedling growth of tumorous stem mustard,and their allelopathic effects had a concentration-dependent manner.It could be presumed that the autotoxicity of tumorous stem mustard is the main cause of continuous cropping obstacle. 展开更多
关键词 germination seedling residues extracts liquids length stronger superoxide catalase peroxidase
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Study on liquid–liquid two-phase mass transfer characteristics in the microchannel with deformed insert
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作者 Qinyan Wang Yang Jin +2 位作者 Jun Li Yongbo Zhou Ming Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第2期114-126,共13页
In this work, the liquid-liquid two-phase mass transfer characteristics in the microchannel with deformed insert were studied. The experiment used di-(2-ethylhexyl) phosphoric acid/kerosene-Cu^(2+)as the mass transfer... In this work, the liquid-liquid two-phase mass transfer characteristics in the microchannel with deformed insert were studied. The experiment used di-(2-ethylhexyl) phosphoric acid/kerosene-Cu^(2+)as the mass transfer evaluation system. The effects of some key factors such as the total flow velocity,channel inner diameter, channel length, insert diameter, extractant concentration on the extraction efficiency and mass transfer coefficient were systematically investigated. Compared with a simple microreactor, the liquid-liquid mass transfer enhancement effect of the insert was quantitatively analyzed. The study found that the regular deformation of the insert could cause fluid interface deformation and promote flow state chaos, effectively increasing the mass transfer rate. And the enhancement effect of the insert was more significant at high flow velocities. The highest mass transfer coefficient in the microchannel with deformed insert was 7.886 s^(-1), the enhancement factor could reach 4.17. And only needed 0.095 s to approach the extraction equilibrium. The deformed center insert exhibited an effective liquid-liquid mass transfer enhancement effect, which can be used as a micro-chemical process enhancement method to be applied in the fields of higher throughput mass transfer and chemical synthesis,and at the same time provide ideas for development and structural optimization of microreactors. 展开更多
关键词 MICROCHANNEL INSERT DEFORMATION liquidliquid extraction Mass transfer enhancement
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Determination of brominated diphenyl ethers in atmospheric particulate matter using selective pressurized liquid extraction and gas chromatography–mass spectrometry with a negative chemical ionization 被引量:3
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作者 Qian Zhang Yongxiao Wang +1 位作者 Guilin Han Tao Liang 《Acta Geochimica》 EI CAS CSCD 2017年第3期531-534,共4页
This study describes the development and validation of a sensitive and reliable method for determination of polybrominated diphenyl ethers(PBDEs)in atmospheric particulate matter using selective pressurized liquid e... This study describes the development and validation of a sensitive and reliable method for determination of polybrominated diphenyl ethers(PBDEs)in atmospheric particulate matter using selective pressurized liquid extraction(SPLE)and gas chromatography–mass spectrometry with a negative chemical ionization(GC-NCI-MS).Extraction and clean-up were performed using PLE with 2 g florisil and 3 g silica placed in the extraction cells.Under optimal conditions,14 PBDEs were extracted at 70℃ using hexane/dichloromethane(50:50,v/v)as solvent.Validation of SPLE returned excellent recoveries for most analytes,with relative standard deviations mostly below20%.Method detection limits ranged from 0.13 to15.38 ng·mL^-1 for the GC-MS analyses.The method was successfully applied to atmospheric particulate matter of Beijing,where analytes were detected in the range of182.79 to 468.99 pg·m^-3. 展开更多
关键词 Brominated diphenyl ethers Atmospheric particulate matters Selective pressurised liquid extraction Gas chromatography-mass spectrometry
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Separation of Red (Y_2O_3:Eu^(3+)), Blue (BaMgAl_(10)O_(17):Eu^(2+)) and Green (CeMgAl_(10)O_(17):Tb^3) Rare Earth Phosphors by Liquid/Liquid Extraction 被引量:3
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作者 梅光军 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期603-607,共5页
A novel process for separation of red (Y2O3:Eu^3+), blue(BaMgAl10O17:Eu^2+) and green (CeMgAl10O17:Tb^3) rare earth fluorescent powders was proposed. At first, the blue powder can be extracted selectively f... A novel process for separation of red (Y2O3:Eu^3+), blue(BaMgAl10O17:Eu^2+) and green (CeMgAl10O17:Tb^3) rare earth fluorescent powders was proposed. At first, the blue powder can be extracted selectively from an aqueous solution using a chelating collector 2-thenoyltrifluoroacetone (TTA) dissolved in heptane at alkaline pH condition, then, chloroform was used for extracting the green powder into organic phase. The red phosphor remains in aqueous phase with potassium sodium tartrate depressant (PST). Therefore, three phosphors can be separated successfully from their artificial mixtures by liquid/liquid extraction, and grades and recovery of separated products reach respectively as follows: red is 96.9% and 95.2%, blue is 82.7% and 98.8%, green is 94.6% and 82.6%. 展开更多
关键词 rare earth phosphor solid-solid separation liquid/liquid extraction
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A highly sensitive SPE-liquid/liquid extraction-RPLC analytical method for the determination of 6β-hydroxycortisol and cortisol in cancer patients' urine 被引量:3
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作者 Zhang Hong Fang Yu Li Ying Liang Aibin 《Journal of Medical Colleges of PLA(China)》 CAS 2010年第2期75-83,共9页
A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods: After SPE column purification and liquid-l... A highly sensitive SPE-liquid/liquid extraction RPLC method has been developed for the analysis of 6β-hydroxycortisol and cortisol in the urine of cancer patients. Methods: After SPE column purification and liquid-liquid extraction, the sample test solutions were analyzed with RPLC using a C18 analytical column. This improved analytical method has been validated for linearity, accuracy (recovery from urine), repeatability (within-day and between-day precision), specificity, sensitivity, and stability. This SPE-liquid/liquid extraction-RPLC is rapid, simple, accurate and reproducible. The technique is particularly useful for monitoring the CYP3A activity of cancer patients in clinical settings. The results are expressed as the ratio of 6β-hydroxycortisol to cortisol. Results: The CYP3A activity from a total of 153 samples was measured using this improved method. Considerable variation in the CYP3A activity of different cancer patients has been documented. Thus, personalized medical treatment based on the individual metabolic enzyme activity level is necessary. Conclusion: This new analytical method facilitates such individualized medical treatments. 展开更多
关键词 Solid phase extraction (SPE) liquid/liquid extraction Reversed-phase high performance liquid chromatography (RPLC) CYP3A 6β-hydroxycortisol/cortisol Cancer
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Synthesis of 2, 6 Bis(1′-Phenyl- 3′- Methyl-5′-Oxopyrazole- 4′) Pyridinediacyl and Its Solid Liquid Extraction Behavior for Ce(Ⅲ) 被引量:1
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作者 邓启良 郭效军 +2 位作者 彭波 高锦章 康敬万 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期420-423,共4页
diketone type chelating ligands have high coordinative activity and selectivity, and are widely applied in analytical chemistry. In order to obtain profounder understanding to the properties of bis(4 acylpyrazolone ... diketone type chelating ligands have high coordinative activity and selectivity, and are widely applied in analytical chemistry. In order to obtain profounder understanding to the properties of bis(4 acylpyrazolone 5), A new 4 acylpyrazol 5 one derivative (H 2BPMPP) was syntheszed, which contains a heterocyclic ring between two 1 phenyl 3 methyl 4 acylpyrazol 5 one rings. The new compound was characterized by element analyses, UV, IR and 1H NMR spectra. The equilibrium of the keto enol tautomerism was studied. The results show that a lower dielectric constant of solvent favors the enol form which has a higher λ max . Due to special merits of paraffin wax, the solid liquid extraction behavior of Ce(Ⅲ) with molten paraffin wax as a diluent was also investigated at higher temperature. The value of the pH 1/2 was 3.19 and the value of log K ex was 3.467. The chemical composition of the complex was obtained by the slope analysis method. 展开更多
关键词 rare earths synthesis H 2BPMPP solid liquid extraction cerium(Ⅲ)
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Comparison of conventional and supported liquid extraction methods for the determination of sitagliptin and simvastatin in rat plasma by LC-ESI-MS/MS 被引量:1
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作者 B.Ramesh N.Manjula +2 位作者 S.R.Bijargi V.U.M.Sarma P.Sita Devi 《Journal of Pharmaceutical Analysis》 SCIE CAS 2015年第3期161-168,共8页
Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC-MS/MS, including (1) liquid-liquid extraction (LLE), (2) solid phase extraction (SPE) and ... Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC-MS/MS, including (1) liquid-liquid extraction (LLE), (2) solid phase extraction (SPE) and (3) supported liquid extraction (SLE). Comparison of recoveries of analytes with different extraction methods revealed that SLE was the best extraction method. The detection was facilitated with ion trap-mass spectrometer by multiple reactions monitoring (MRM) in a positive ion mode with ESI. The transitions monitored were m./z 441.1→325.2 for simvastatin, 408.2→235.1 for sitagliptin and 278.1→260.1 for the IS. The lower limit of quantification (LLOQ) was 0.2 ng/mL for sitagliptin and 0.1 ng/mL for simvastatin. The effective SLE offers enhanced chromatographic selectivity, thus facilitating the potential utility of the method for routine analysis of biological samples along with pharmacokinetic studies. 展开更多
关键词 Rat plasma SIMVASTATIN Sita#'ptin Supported liquid extraction
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Direct injection HILIC-MS/MS analysis of darunavir in rat plasma applying supported liquid extraction 被引量:2
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作者 Bokka Ramesh Nemali Manjula +1 位作者 Sistla Ramakrishna Potturi Sita Devi 《Journal of Pharmaceutical Analysis》 SCIE CAS 2015年第1期43-50,共8页
A novel bioanalytical method was developed and validated for the quantitative determination of darunavir(DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry(HILIC-MS... A novel bioanalytical method was developed and validated for the quantitative determination of darunavir(DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry(HILIC-MS/MS) with supported liquid extraction(SLE).lrbesartan(IRB) was used as an internal standard(IS).The analyte in rat plasma(200 μL) was isolated through SLE using ethyl acetate as the eluting solvent.The chromatographic separation was achieved on Luna-HILIC(250 mm × 4.6 mm,5 μm)column with a mobile phase of 0.1% of formic acid in water:acetonitrile(5:95,v/v),at a constant flow rate of 1.0mL/min.The MS/MS ion transitions for DRV(548.1→392.0) and IS(429.2→207.1) were monitored on an ion trap mass spectrometer,operating in the multiple reaction monitoring(MRM) mode.The lower limit of quantitation(LLOQ) was 0.2 ng/mL and quantitation range was 0.2-5000 ng/mL.The method was validated for its selectivity,sensitivity,carryover,linearity,precision,accuracy,recovery,matrix effect and stability.The method was successfully applied to pharmacokinetic study in rats. 展开更多
关键词 Darunavir HILIC-MS/MS Rat plasma Supported liquid extraction
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Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry 被引量:4
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作者 SHAN Xiao Mei SHEN Deng Hui +2 位作者 WANG Bing Shuang LU Bei Bei HUANG Fa Yuan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第6期471-474,共4页
To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry ... To establish an analytical method for determination of four bisphenols (BPA, BPB, BPF, and BPS) and two alkylphenols (4-n-OP, 4-n-NP) in water by ultra performance liquid chromatography- tandem mass spectrometry (UPLC/MS/MS). The water samples were extracted and condensed with solid-phase extraction (SPE) using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%. 展开更多
关键词 UPLC BPA Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance liquid Chromatography-tandem Mass Spectrometry MASS
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Liquid chromatography tandem mass spectrometry method for the estimation of lamotrigine in human plasma:Application to a pharmacokinetic study 被引量:4
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作者 Santosh Ghatol Vatsal Vithlani +3 位作者 Sanjay Gurule Arshad Khuroo Tausif Monif Pankaj Partani 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第2期75-83,共9页
A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standa... A reliable,selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine13C3,d3 as an internal standard.Analyte and internal standard were extracted from human plasma by solid-phase extraction and detected in positive ion mode by tandem mass spectrometry with electrospray ionization(ESI) interface.Chromatographic separation was performed on a Chromolith s SpeedROD;RP-18e column(50-4.6 mm i.d.) using acetonitrile:570.1 mM ammonium formate solution(90:10,v/v) as the mobile phase at a flow rate of 0.500 mL/min.The calibration curves were linear over the range of 5.02-1226.47 ng/mL with the lower limit of quantitation validated at 5.02 ng/mL.The analytes were found stable in human plasma through three freeze(-20℃)-thaw(ice-cold water bath) cycles and under storage on bench-top in ice-cold water bath for at least 6.8 h,and also in the mobile phase at 10℃ for at least 57h.The method has shown good reproducibility,as the intra-and inter-day precisions were within 3.0%,while the accuracies were within 76.0% of nominal values.The validated LC-MS/MS method was applied for the evaluation of pharmacokinetic and bioequivalence parameters of lamotrigine after an oral administration of 50mg lamotrigine tablet to thirty-two healthy adult male volunteers. 展开更多
关键词 Lamotrigine liquid chromatography/tandem mass spectrometry Solid phase extraction Pharmacokinetic study
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Application of silver-based dihydric alcohol to the extraction of methyl linolenate with high extractability and stability replacing ionic liquids
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作者 Qianxia Chen Xianghong Lu Jianbing Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期871-880,共10页
A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18... A novel silver-based dihydric alcohol extractant was substituted for ionic liquids to enrich methyl linolenate(C18-3)from tallow seed oil methyl ester in this study.The interactions among dihydric alcohol,Ag(I)and C18-3 were explored by FT-IR spectroscopy.The effects of dihydric alcohol structure,carrier Ag(I)concentration,temperature and initial feed concentration on extraction yield and selectivity were reported.The good extraction performance was achieved by 1,4-butanediol containing AgBF4.The complexation of Ag(I)with C18-3 was dominant in extraction operation rather than physical partition.Furthermore,a multi-step reverse extraction method was proposed to obtain C18-3 product and regenerate the extractant.1-Hexene as the stripping phase can facilitate C18-3 reverse extraction.The content of C18-3 in the product was up to 93.36%,and the yield was 73.76%.This work opened a new route for the utilization of the dihydric alcohol properties to manipulate the carrier efficiency for extracting unsaturated fatty acid methyl esters at a lower cost. 展开更多
关键词 liquidliquid extraction Dihydric alcohol COMPLEXATION AgBF4 Reverse extraction
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Transport Behaviour of La^(3+) with Flat-Sheet-Sandwich Supported Liquid Membrane Extraction System
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作者 易涛 严纯华 +5 位作者 李标国 李洁 朱国斌 杜启云 王利生 胡小平 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第2期81-84,共4页
This paper suggested a modified model of SLM which could improve its stability.In the model, an organic solution was sandwiched between two layers of supported film,which we called sandwich supported liquid membrane(S... This paper suggested a modified model of SLM which could improve its stability.In the model, an organic solution was sandwiched between two layers of supported film,which we called sandwich supported liquid membrane(SSLM).The transport experiments of La3+ were performed with SSLM containing HEH(EHP)as a carrier. The permeability coefficient (p) of La3+ were measured and some factors affecting the p were investigated. The results showed that if the pH of the feed was below 4.0,the p was increased with increasing in pH. The p was also increased when the strip acidity increases.Inspite of not enough satisfactory reproducibility on test result, the stability of the model was improved. 展开更多
关键词 liquid membrane extraction LANTHANUM Permeability coefficient HEH(EHP) Flat-Sheet-Sandwich
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Transport Behaviour of La^(3+) with Hollow Fiber Sandwich Liquid Membrane Extraction System
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作者 朱国斌 李洁 +5 位作者 杜启云 王利生 胡小平 严纯华 易涛 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第4期252-256,共5页
The extraction of La ̄(3+) with hollow fiber sandwich liquid membrane was described in present paper. The theoretical equations of mass transport for this system were deduced. The permeability coefficient p of mass tr... The extraction of La ̄(3+) with hollow fiber sandwich liquid membrane was described in present paper. The theoretical equations of mass transport for this system were deduced. The permeability coefficient p of mass transport and its related factors were observed experimentally. The p value was increased with increase of pH in the feed and became constant under the condition of pH over 4. The p value was the highest when the flow rate was at 30 ml/min. The value of the coefficient was lower than that of single hollow fiber supported liquid membrane under the same conditions, but the stability and concentrated capacity of the sandwich membrane was better. 展开更多
关键词 LANTHANUM liquid membrane extraction Hollow fiber Permeability coefficient HEH ( EHP )
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Optimization of Ultrasonic Extraction and Clean-up Protocol for the Determination of Polycyclic Aromatic Hydrocarbons in Marine Sediments by High-performance Liquid Chroma-tography Coupled with Fluorescence Detection 被引量:1
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作者 PENG Xuewei YAN Guofang +3 位作者 LI Xianguo GUO Xinyun ZHOU Xiao WANG Yan 《Journal of Ocean University of China》 SCIE CAS 2012年第3期331-338,共8页
The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were pu... The procedures of ultrasonic extraction and clean-up were optimized for the determination of polycyclic aromatic hydrocarbons (PAHs) in marine sediments. Samples were ultrasonically extracted, and the extracts were purified with a miniaturized silica gel chromatographic column and analyzed with high performance liquid chromatography (HPLC) with a fluorescence detector. Ultrasonication with methanol-dichloromethane (2:1, v/v) mixture gave higher extraction efficiency than that with dichloromethane. Among the three elution solvents used in clean-up step, dichloromethane-hexane (2:3, v/v) mixture was the most satisfactory. Under the optimized conditions, the recoveries in the range of 54.82% to 94.70% with RSDs of 3.02% to 23.22% for a spiked blank, and in the range of 61.20% to 127.08% with RSDs of 7.61% to 26.93% for a spiked matrix, were obtained for the 15 PAHs studied, while the recoveries for a NIST standard reference SRM 1941b were in the range of 50.79% to 83.78% with RSDs of 5.24% to 21.38%. The detection limits were between 0.75 ng L-1 and 10.99 ng L-1for different PAHs. A sample from the Jiaozhou Bay area was examined to test the established methods. 展开更多
关键词 ultrasonic extraction marine sediment polycyclic aromatic hydrocarbon high performance liquid chromatography
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Transport of yttrium metal ions through fibers supported liquid membrane solvent extraction
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作者 A.G.Gaikwad A.M.Rajput 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第1期1-6,共6页
A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liqu... A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liquid membrane was impregnated with different concentrations carrier.The experimental variables explored were concentration of yttrium(Ⅲ) ions,pH of source phase,PC-88A concentration in membrane phase,acid concentration in receiving phase and stirring speed.The pre-concentration of yttrium(Ⅲ) ions ... 展开更多
关键词 fibers supported liquid membrane solvent extraction yttrium metal ion channel EXTRACTION STRIPPING PC-88A rare earths
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Comparison between sequential and single extraction procedures for metal speciation in fresh and dried Sedum Plumbizincicola 被引量:4
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作者 宋祖威 仲兆平 +2 位作者 钟道旭 吴龙华 骆永明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期487-494,共8页
Sequential and single extraction procedures were applied to both fresh and dried Sedum Plumbizincicola leaves and stems.The extractants, different from those of soil, sediment or sewage sludge metal fractions, were wa... Sequential and single extraction procedures were applied to both fresh and dried Sedum Plumbizincicola leaves and stems.The extractants, different from those of soil, sediment or sewage sludge metal fractions, were water, 80%(v/v) ethanol, 1 mol/L Na Cl,2% HAc and 0.6 mol/L HCl. Zn, Cd and Cu in the extracts and samples were measured by flame atomic adsorption spectrometry. In sequential extraction procedures, water soluble form and ethanol soluble form are the main fractions for Zn, while water soluble form and Na Cl soluble form for Cd, and comparatively uniform distribution for Cu with the residue form most and HCl soluble form second. Single extraction procedures are used to compare the extraction efficiencies of the five reagents to screen appropriate extractants and operating conditions for liquid extraction to deal with large amount of harvested metal-contained biomass, which will pose a threat to the environment if treated improperly. The sequences of extraction efficiencies are HCl>Na Cl≈HAc>Water≈Ethanol for Zn and HCl≈Na Cl≈HAc>Water>Ethanol for Cd. As for Cu, all the five extractants cannot effectively extract Cu, but HCl achieves a higher efficiency(>70% in fresh samples, and 45%-60% in dried samples). Besides, extraction efficiencies for most extractants in fresh samples are higher than those in dried samples, and extraction efficiencies of stems and leaves for the five extractants are close. The two extraction procedures can obtain high degree of accuracy with the relative standard deviation(RSD)lower than 10%, and metal recoveries are controlled between 80%-120% with most of 90%-110%. 展开更多
关键词 Sedum Plumbizincicola liquid extraction biomass disposal heavy metals
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Prediction of dispersed phase holdup in pulsed disc and doughnut solvent extraction columns under different mass transfer conditions 被引量:3
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作者 Yong Wang Kathryn H.Smith +3 位作者 Kathryn Mumford Teobaldo F.Grabin Zheng Li Geoffrey W.Stevens 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第2期226-231,共6页
Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is present... Using experimental data from a number of pulsed disc and doughnut solvent extraction columns, a unified correla- tion for the prediction of dispersed phase holdup that considers the effects of mass transfer is presented. Pulsed disc and doughnut solvent extraction columns (PDDC) have been used for a range of important applications such as ura- nium extraction and nuclear fuel recycling. Although the dispersed phase holdup in a PDDC has been presented by some researchers, there is still the need to develop a robust correlation that can predict the experimental dispersed phase holdup over a range of operating conditions including the effects of mass transfer direction. In this study, dis- persed phase holdup data from different literature sources for a PDDC were used to refit constants for the correlation presented by Kumar and Hartland lind. Eng. Chem. Res.,27 (1988),131-138] which did not consider the effect of col- umn geometry. In order to incorporate the characteristic length of the PDDC (i.e. the plate spacing), the unified cor- relation for holdup proposed by Kumar and Hartland based on data from eight different types of columns [Ind. Eng. Chem. Res.,34 (1995) 3925-3940] was refitted to the PDDC data. New constants have been presented for each hold- up correlation for a PDDC based on regression analysis using published holdup data from PDDCs that cover a range of onerating conditions and nhwical nronerties and consider the direction of mass transfer. 展开更多
关键词 Solvent extraction liquid extraction Pulsed disc and doughnut columns Solvent extraction column design Holdup Dispersed phase holdup Hydrodynamics of extraction columns
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Kinetic study on reactive extraction of phenylalanine enantiomers with BINAP-copper complexes 被引量:1
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作者 唐课文 罗菁菁 +3 位作者 张盼良 易健民 华杰 杨长安 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期57-63,共7页
Enantioselective liquid–liquid extraction has attracted considerable attention for its potential use in largescale production. Kinetic data are needed for the reliable scale-up of the process. This paper reports the ... Enantioselective liquid–liquid extraction has attracted considerable attention for its potential use in largescale production. Kinetic data are needed for the reliable scale-up of the process. This paper reports the kinetic study of reactive extraction of phenylalanine(Phe) enantiomers with BINAP–copper complex(BINAP–Cu) as a chiral selector. The theory of extraction accompanied by a chemical reaction was applied.The effects of agitation speed, interfacial area, p H value of aqueous phase, initial concentration of Phe enantiomers and initial concentration of BINAP–Cu on the specific rate of extraction were investigated. The forward rate constants of the reactions in the reactive extraction process are 7.93 × 10-5m5/2·mol-1/2·s-1for D-Phe and 1.29 × 10-4m5/2·mol-1/2·s-1for L-Phe. 展开更多
关键词 KINETICS Amino acids Modeling liquidliquid extraction ENANTIOMERS
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Determination of berberine in Phellodendron amurense from different sites of Changbai Mountain 被引量:2
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作者 Lin Ma Jun-qing Li Yuan-dong Hu 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期201-207,共7页
Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active c... Phellodendron amurense has been used for many years as a medical plant in traditional Chinese medicine and has shown great prospect in recent clinical trials for future applications. Berberine is an essential active compound contained in P. amurense. Our objective in this study was to quantify the content of berberine in P.amurense from sites at different elevations on Changbai Mountain. We collected samples of P. amurense from five different elevations on Changbai Mountain. Berberine in samples was extracted by ultrahigh pressure extraction(UPE). And the quantity was measured by high performance liquid chromatography(HPLC). First, the optimal HPLC conditions for berberine were identified with satisfactory precision(relative standard deviation, R SD/5.6 %), good accuracy(relative error, R E/ 3.6 %) and good linear relation(R2= 0.9998) in the range of 6.576–328.8 mg L-1. Second, the combination of UPE and HPLC methods in quantitative analysis of berberine showed high repeatability(R SD= 3.28 %), reproducibility(R SD= 4.72 %),stability(R SD/ 1.27 %) and good recovery(99.54 %) for real plant materials. Samples from Heilongjiang Province at the lowest elevation contained the highest amount of berberine.Similarly, the lowest amount of berberine was recorded in samples from Changbai Forest Bureau of Jilin Province collected at the highest elevation in this paper. The proposed UPE–HPLC method is simple, reliable and low-cost for quantitative analysis of berberine. Content of berberine in P.amurense varied significantly by site on Changbai Mountain. 展开更多
关键词 Phellodendron amurense Berberine Changbai Mountain Altitudes Ultrahigh pressure extraction High performance liquid chromatography
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Enrichment of Trace Scandium with Microcrystalline Naphthalene and Subsequent ICP-AES Determination
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作者 Xiong Hongchun, Liao Zhenhuan, Peng Tianyou, Deng Zhonghua, Jiang Zucheng(College of Chemistry, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第2期205-208,共4页
A new method is proposed to preconcentrate and separate trace scandium from a large volume of aqueous solution by solid liquid extraction with microcrystalline naphthalene. Scandium oxinate can be adsorbed onto microc... A new method is proposed to preconcentrate and separate trace scandium from a large volume of aqueous solution by solid liquid extraction with microcrystalline naphthalene. Scandium oxinate can be adsorbed onto microcrystalline naphthalene quantitatively under certain conditions. The effects of various experimental parameters have been optimized. The influence of additive of cobalt (II) on recovery of scandium (III) is studied in detail. The proposed method has been used for determination of Sc in Certified Reference Material of “Vehicle Exhaust Particulates”. 展开更多
关键词 Key words scandium COBALT microcrystalline naphthalene inductively coupled plasma atomic emission spectrometry (ICP AES) solid liquid extraction
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