祝凌燕
博士 教授
南开大学 环境科学与工程学院
持久性有机污染物(POPs)在环境中的迁移、转化与归宿;污染生态化学;环境分析与监测;污染控制与生态修复;
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- 姓名:祝凌燕
- 目前身份:在职研究人员
- 担任导师情况:
- 学位:博士
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学术头衔:
国家杰出青年科学基金获得者
- 职称:高级-教授
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学科领域:
环境工程学
- 研究兴趣:持久性有机污染物(POPs)在环境中的迁移、转化与归宿;污染生态化学;环境分析与监测;污染控制与生态修复;
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3579
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646
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成果数
15
祝凌燕, Lingyan Zhu, Chiew Boon Tay, Hian Kee Lee*
Journal of Chromatography A, 963 (2002) 231-237,-0001,():
-1年11月30日
A simple preconcentration and clean-up liquid-liquid-liquid microextraction of aromatic amines is described in this paper. The compounds were extracted from 2.0µl aqueous samples (donor phase) into an organic phase, layered on the donor phase, and then back extracted to a microdrop of aqueous receiving phase, suspended in the organic phase. After extraction, the microdrop was injected into the HPLC system directly for analysis. Optimal conditions of the extraction were donor phase (a): 2 ml of water sample adjusted to pH 13 with NaOH-NaCl; organic phase (o), 150ml ethyl acetate; and 1 receiving phase (a) of 2µl aqueous solution at pH 2.1. The a→o extraction time was 15min and for o→a, 30s. 212 18-Crown-6 ether, which can complex with amine, was added to the aqueous receiving phase to improve the extraction performance. Enrichment factors ranged from 218 (for 4-nitroaniline) to 378 (for 4-chloro-2-aniline). The calibration curve 2 for these anilines was linear within the range 2.5ng/ml-2.5mg/ml (r 50.998). Detection limits ranged from 0.85 to 1.80ng/ml (at S/N53). This procedure can be a selective preconcentration method for aromatic amines present in water samples. 2002 Elsevier Science B.V. All rights reserved.
Liquid-liquid-liquid microextraction, Extraction methods, Water analysis, Environmental analysis, Amines,, aromatic
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祝凌燕, Chuanhong Tu, ingyan Zhu, Chay Hoon Ang, Hian Kee Lee
Electrophoresis 2003, 24, 2188-2192,-0001,():
-1年11月30日
Large-volume sample stacking (LVSS) is an effective on-capillary sample concentration method in capillary zone electrophoresis, which can be applied to the sample in a low-conductivity matrix. NaOH solution is commonly used to back-extract acidic compounds from organic solvent in sample Fretreatment. The effect of NaOH as sample matrix on LVSS of haloacetic acids was investigated in this study. It was found that the presence of NaOH in sample did not compromise, but rather help the sample stacking performance if a low pH background electrolyte (BGE) was used. The sensitivity enhancement factor was higher than the case when sample was dissolved in pure water or diluted BGE. Compared with conventional injection (0.4% capillary volume), 97-120-fold sensitivity enhancement in terms of peak height was obtained without deterioration of separation with an injection amount equal to 20% of the capillary volume. This method was applied to determine haloacetic acids in tap water by combination with liquid-liquid extraction and back-extraction into NaOH solution. Limits of detection at sub-ppb levels were obtained for real samples with direct UV detection.
Capillary zone electrophoresis, Haloacetic acids, Large-volume sample stacking
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【期刊论文】Determination of Polybrominated Diphenyl Ethers in Environmental Standard Reference Materials
祝凌燕, Lingyan Y. Zhu and Ronald A. Hites*
Anal. Chem. 2003, 75, 6696-6700,-0001,():
-1年11月30日
The total concentrations (ΣPBDE) of 15 polybrominated diphenyl ethers, BDEs 17, 28, 47, 49, 66, 71, 85, 99, 100, 138, 153, 154, 183, 190, and 209, and a predominant polybrominated biphenyl (PBB) congener, 2,2´,4,4´,5,5´-polybrominated biphenyl (PBB-153) were determined in six natural matrix Standard Reference Materials (SRM) provided by the National Institute of Standards and Technology (NIST). The ΣPBDE concentrations (±one standard deviation) in SRM 1945 (whale blubber), SRM 1946 (fish tissue), SRM 1947 (fish tissue), and SRM 1974b (mussel tissue) were ±126, 7±79, 3±134, 5, and 7.9±0.2ng/g of wet wt, respectively. The ΣPBDE concentrations were 54±2 and 163±4ng/g of dry wt for SRM 2977 (mussel tissue) and SRM 2978 (mussel tissue), respectively. Among the three kinds of marine animals, mussel tissue had the lowest total concentration of PBDEs. These values can provide an informal reference or benchmark to laboratories who measure these compounds.
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祝凌燕, Lingyan Zhu, Chuanhong Tu, and Hian Kee Lee*
Anal. Chem. 2002, 74, 5820-5825,-0001,():
-1年11月30日
An easy, simple, and highly efficient on-line preconcentration method for acidic compounds in capillary electrophoresis was investigated. It combined two on-line concentration techniques, field-amplified sample injection (FASI) and sweeping. A low-pH (2.5) background electrolyte was used to suppress the electroosmotic flow (EOF), obviating the need of a coated capillary, as well as to neutralize the weakly acidic analytes. After injection of a plug of water inside the separation capillary, negative voltage was applied to initialize FASI for a much longer time than usual. The anions experienced a high electric field and moved quickly to the boundary of the water and the low-pH nonmicellar electrolyte. When the anions encountered the low-pH electrolyte, they were neutralized and a focused sample zone was formed. Then both inlet and outlet vials were changed to those Containing the lowp Hmicellar background electrolyte. As negative voltage was applied, the anionic micelles moved into the capillary, and sweeping and separation began. The novelty in the present procedure is that a low-pH buffer is used to suppress the EOF and also the ionization of the analytes, without need of any other additives or use of a coated capillary. This method afforded 100 000-fold improvement in peak heights for some phenoxy acidic herbicides. The detection limits for these compounds could be low as 100pg/mL.
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祝凌燕, Lingyan Zhu, Kim Huey Ee, Limian Zhao, Hian Kee Lee*
Journal of Chromatography A, 963 (2002) 335-343 ,-0001,():
-1年11月30日
A preconcentration technique, which involves liquid–liquid–liquid microextraction, was developed to determine phenoxy herbicides in bovine milk. A layer of organic phase was impregnated into the pores of a 3.5cm long porous hollow fiber, while the internal volume of the fiber was filled with NaOH solution (the acceptor solution) that was connected directly to the needle of a microsyringe. The fiber was then immersed into 8ml of acidified milk sample. When the sample solution was stirred, acidic analytes were extracted into the organic phase and back extracted simultaneously into the alkaline acceptor medium as the analytes were protonated at low pH and deprotonated at high pH. After extracting for a prescribed time, 5ml acceptor solution was taken back into the syringe and injected directly into a HPLC system for quantification. The analytes were extracted quantitatively from the sample solution into the acceptor solution with a large enrichment factor of 900. Due to its low cost, the hollow-fiber extraction device was disposed of after a single extraction that eliminated the possibility of carry over effects. In addition, because a small volume of organic solvent was required and little waste is generated, the procedure is environmentally friendly, and is compatible with the "green chemistry" concept.
Liquid-liquid-liquid microextracion, Extraction methods, Milk, Food analysis, Membrane extraction, Hollow-fiber membranes, Phenoxy acids, Pesticides
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祝凌燕, Lingyan Zhu a), Su YIn Tham a), Adrian U.J. Yap b), Htan Kee Lee a)
J. Sep. Sci, 2002. 15. 1-6,-0001,():
-1年11月30日
The release of fluoride is an impodant factor in evaluating a composite restorative material due to its anticariogenic effect, Field amplified stacking injection in capillary electrophoresis was studied to determine the concentration of fluoride released from dental restorative materials, A detection limit of 20ng/mL was obtained with good reproducibility (relative standard deviation <4%), The method was applied to the ana-lysis of fluoride released from four different types of commercially available dental composites ever 28 days. Resutis showed that fiald-amplified stacking injection-capil-lary electrophoresis was effective in monitoring the fluonde release process and pro- duct quality of different kinds of restorative materials,
Cedillary elect rophoresis, Field-amplified stacking, Dental restorative ma-terials, Fluoride release
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祝凌燕, Lingyan Zhu, Liang Zhu, Hian Kee Lee*
Journal of Chromatography A, 924 (2001) 407-414 ,-0001,():
-1年11月30日
A simple liquid-liquid-liquid microextraction device utilizing a 2cm 30.6mm I.D. hollow fiber membrane was used to preconcentrate nitrophenols from water sample prior to capillary liquid chromatography (cLC) analysis. The extraction procedure was induced by the pH difference inside and outside the hollow fiber. The donor phase outside the hollow fiber was adjusted to pH~1 with HCl; the acceptor phase was NaOH solution used at various concentrations. Organic solvent was immobilized into the pores of the hollow fiber. With stirring, the neutral nitrophenols outside the fiber were extracted into the organic solvent, then back extracted into 2ml of basic acceptor solution inside the fiber. The acceptor phase was then withdrawn into a microsyringe and injected into the cLC system directly. This technique used a low-cost disposable extraction "device" and is very convenient to operate. Up to 380-fold enrichment of analytes could be achieved. This procedure could also serve as a sample clean-up step because large molecules and basic compounds were not extracted into the acceptor phase. The RSD (n56) was less than 6.2%, while the linear calibration range was from 1 to 200 mg/ml with r.0.998. The procedure was applied to the analysis of seawater.
Liquid-liquid-liquid microextraction, Extraction methods, Hollow-fiber membranes, Water analysis, Environmental analysis, Nitrophenols
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祝凌燕, Lingyan Zhu and Hian Kee Lee*
Anal. Chem. 2001, 73, 3065-3072,-0001,():
-1年11月30日
A procedure that combines two common stacking techniques, field-amplified sample injection and water removal, with an electroosmotic flow pump, is used to separate phenoxy acid herbicides by capillary zone electrophoresis. Before sample loading, a long plug of water was hydrodynamically injected into the capillary both to serve as the medium to permit a high electric field strength and to contain sample anions. Because of this long length of water, the number of ions injected into the capillary was greatly increased. Electrokinetic injection at reversed voltage was then used for introducing negatively charged ions from the diluted sample into the column. The water was removed from the capillary using the electroosmotic flow (EOF) pump when the EOF of the background electrolyte was suppressed. This method afforded a sensitivity enhancement of greater than 3000 times. Combined with solid-phase extraction, detection limits for the phenoxy acid herbicides as low as 0.01ng/mL could be achieved.
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【期刊论文】Dechlorane Plus, a Chlorinated Flame Retardant, in the Great Lakes
祝凌燕, EUNHA HOH, LINGYAN ZHU, AND RONALD A. HITES*
ENVIRON. SCI. & TECHNOL VOL. xx, NO.xx, xxxx,-0001,():
-1年11月30日
A highly chlorinated flame retardant, Dechlorane Plus (DP), was detected and identified in ambient air, fish, and sediment samples from the Great Lakes region. The identity of this compound was confirmed by comparing its gas chromatographic retention times and mass spectra with those of authentic material. This compound exists as two gas chromatographically separable stereoisomers (syn and anti), the structures of which were characterized by one-and two-dimensional proton nuclear magnetic resonance. DP was detected in most air samples, even at remote sites. The atmospheric DP concentrations were higher at the eastern Great Lakes sites (Sturgeon Point, NY, and Cleveland, OH) than those at the western Great Lakes sites (Eagle Harbor, MI, Chicago, IL, and Sleeping Bear Dunes, MI). At the Sturgeon Point site, DP concentrations once reached 490 pg/m3. DP atmospheric Concentrations were comparable to those of BDE-209 at the eastern Great Lakes sites. DP was also found in sediment cores from Lakes Michigan and Erie. The peak DP concentrations were comparable to BDE-209 concentrations in the sediment core from Lake Erie but were about 30 times lower than BDE- 209 concentrations in the core from Lake Michigan. In the sediment cores, the DP concentrations peaked around 1975-1980, and the surficial concentrations were 10-80% of peak concentrations. Higher DP concentrations in air samples from Sturgeon Point, NY, and in the sediment core from Lake Erie suggest that DP's manufacturing facility in Niagara Falls, NY, may be a source. DP was also detected in archived fish (walleye) from Lake Erie, suggesting that this compound is, at least partially, bioavailable.
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【期刊论文】Identification of Brominated Carbazoles in Sediment Cores from Lake Michigan
祝凌燕, LINGYAN ZHU ANDRONALD A. HITES*
Environ. Sci. Technol. 2005, 39, 9446-9451,-0001,():
-1年11月30日
During the analysis of brominated flame retardants in sediment cores taken from Lake Michigan, a group of unknown brominated compounds were observed. To identify their chemical structures, a variety of gas chromatographic mass spectrometric techniques were used. With the help of high-resolution and positive chemical ionization mass spectrometry, the molecular formula of the most abundant congener was established to be C12H5Br4N. On the basis of the electron impact and electron capture negative ionization mass spectra, this chemical was suspected of being a tetrabromocarbazole. The structure was confirmed by comparing the mass spectra and gas chromatographic retention times of an authentic standard of 1,3,6,8-tetrabromocarbazole with those of the most abundant unknown. The other unknown compounds may be other bromocarbazole congeners. The time trend determined by measuring these compounds as a function of depth in the Lake Michigan sediment cores indicated that the concentration of 1,3,6,8-tetrabromocarbazole peaked around 1920-1935. This is the first time that bromocarbazoles have been found in the environment.
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