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1.
应用离子淌度谱仪在负高压方式下测得苯酚、2-氯代酚、2,4-二氯代酚及五氯代酚的折合淌度值分别为2.12、2.01、1.93、1.74 cm2V-1s-1,检测限分别为 1.0、0.1、0.5、0.5μg/L,2-氯代酚、2,4-二氯代酚的二聚体的折合淌度值分别为 1.60、1.47cm2V1s1,并对苯酚、2-氯代酚和2,4-二氯代酚的混合物进行了分析测定,并讨论了淌度值与分子量、分子形状之间的关系。  相似文献   

2.
几种挥发性有机酚的离子淌度谱研究   总被引:1,自引:1,他引:0  
郭岩  陆妙琴 《分析化学》1997,25(8):951-954
篱子淌度谱仪在负高压方式下测得苯酚、2-氯代酚、2,4-二氯代酚及五氯代酚的折合淌度值分别为2.12、2.01、1.93、1.74cm^2V^-1s^-1,检测限分别为1.0、0.1、0.5、0.5μg/L,2-氯代酚、2,4-二氯代酚的二聚体折合沿度值分别为1.60、1.47cm^2V^-1S^-1,并对苯酚、进行了分析测定,并讨论了淌度值与分子量,佞子形状之间的关系。  相似文献   

3.
测定N-亚硝基化合物的分光光度法   总被引:6,自引:0,他引:6  
沈彬  朱建华  须沁华 《分析化学》1998,26(12):1478-1480
利用N-亚硝基化合物的化学去亚硝基反应,建立了一种间接测定N-亚硝基化合物的分光光度法。实验结果表明,N-二苯基亚硝胺在 0 2~ 9.0 mg/L浓度范围内呈线性关系。该法应用于香烟烟丝及侧流烟雾卒取液的分析,4次测定RSD及回收率分别为1.86%~6.32%,86.2%~96.6%;3.01%~5.03%,101.1%~109.1%。  相似文献   

4.
测定N—亚硝基化合物的分光光度法   总被引:2,自引:0,他引:2  
沈彬  朱建华 《分析化学》1998,26(12):1478-1480
利用N-亚硝基化合物的化学去亚硝基反应,建立了一种间接测定N-亚硝基化合物的分光光度法。实验结果表明,N-二苯基亚硝胺在0.2 ̄9.0mg/L浓度内呈线性关系。该法应用于香烟烟丝及侧流烟雾萃取液的分析,4次测定RSD及回收率分别为1.86% ̄6.32%,86.2% ̄96.6%;3.01% ̄5.03%,101.1% ̄109.1%。  相似文献   

5.
油脂中九种抗氧化剂的反相高效液相色谱法分离和测定   总被引:19,自引:0,他引:19  
研究了油脂中9种酚类抗氧化剂的色谱保留行为,以甲醇-水-乙酸体系为流动相,采用梯度洗脱,可在30min内将九种物质完全分离并定量测定。测定的线性范围1 ̄200mg/l(r=0.9985 ̄0.9997),检测限为2mg/kg,回收率为82.4% ̄98.7%,RSD为1.01% ̄4.74%。  相似文献   

6.
报道了以2′,7′-二氯荧光素(DCF)为指示剂,荧光法间接测定痕量酚的新方法。在0.5mol/LH2SO4介质中,Br-和BrO-3反应生成Br2,Br2与2′,7′-二氯荧光素反应,使2′7′-二氯荧光素荧光猝灭,当加入酚时,酚的溴代反应使体系荧光增强。pH4.0~6.0范围内,该体系激发波长,发射波长分别为λex505nm,λem520nm。酚浓度在1.6~52ng/L范围内呈线性关系,检出限为1.6ng/L。本法选择性好,用于环境水样中酚的测定,结果满意。  相似文献   

7.
痕量硝基酚的反相高效液相色谱电化学检测   总被引:10,自引:0,他引:10  
蒋淑敏  傅承光 《分析化学》1997,25(3):286-289
本文以甲醇与0.03mol/L邻苯二甲酸氢钾缓冲液为淋洗液,采用安培型电化学检测,实现了2-硝基苯酚,3-硝基苯酚,4-硝基苯酚及2,4-二硝基苯酚和2,6-0二硝基苯酚等五种酚类化合物于Perkin-Elmer Nucleosil C8柱上反相高效液相色谱的分离及在E=+1.2V时于玻碳电极上的同时检测。  相似文献   

8.
大黄酚在0.15mol/L HAc-NaAc(pH4.9)底液中,出现一灵敏的示波极谱导数峰,峰电位为-0.45V(vs,SCE),峰电流与大黄酚浓度在2.0×10^-7-5.0×10^-6mol/L范围内成线性关系,检测限为2.0×10^-6mol/L。用于生药大黄中大黄酚的测定,回收率为92.4%-108.4%。用多种电化学手段研究体系的电化学行为,测得电极反应电子数n=2。体系具有吸附性,并  相似文献   

9.
本文介绍了石墨炉原子吸收光谱法测定天然饮用矿泉水中的钼。水样不需浓缩萃取直接测定。线性范围0.02~1.6ng,检测限0.01ng,相对标准偏差2.3%-4.5%,回收率96%-103%。  相似文献   

10.
碘的凝胶色谱测定方法   总被引:6,自引:1,他引:6  
丁朝武  李华斌 《分析化学》1997,25(5):586-589
建立了碘折凝胶色谱测定方法。色谱条件为:Shim-pack DIOL-150柱;流动相甲醇0.01mol/L H3PO4(10:90)流速为1.2mL/min;柱温为35℃,检测波长为224nm;线性范围是0.010-1.0mg/L,相关系数为0.9993,检测限为0.001mg/L,相对标准偏差为1.2%-4.6%;回收率为91%-98%。所建立的方法已用于食盐,尿,系带等样品的测试,均取得较好  相似文献   

11.
An online adsorption-high-performance liquid chromatography (HPLC) method was developed for the determination of phenols (11 priority water pollutants) in waters, using polystyrene chemically modified with N-vinyl-2-pyrrolidone (Strata-X). The detection limits for phenols obtained using a preconcentration from 10 mL of water and calculated by different means vary from 0.3 to 2 μg/L. The accuracy of the determination of phenols in tap and river water samples was verified by the standard addition method.  相似文献   

12.
近年来气相色谱法、薄层色谱法和高效液相色谱法已成为应用最广的测定酚类的方法。Tsuruta等提出了对酞内酰胺苯甲酰氯(4-2(phthalimidyl)benzoyl chloride,简称PIB-Cl)的合成方法,并将PIB-Cl作为胺类和醇类化合物的荧光衍生化试剂,但将它与酚类化合物进行衍生反应及相应的色谱应用还未见报道。本文提出了PIB-Cl与酚的反应,并以苯酚  相似文献   

13.
示波电位—动力学分析法测定环境水样中的酚   总被引:6,自引:1,他引:6  
吴庆生  丁亚平 《分析化学》1995,23(6):696-698
  相似文献   

14.
A flow injection (FI) method with a biamperometric detector, based on the biamperometry for an irreversible redox couple, is described for the determination of phenols in environmental wastewater. The method relies on coupling of the oxidation of phenols at one platinum-wire electrode with the reduction of MnO4- at another platinum wire electrode to enable biamperometric detection with an applied potential difference of 0 V. The linear dynamic range for the dependence of current on phenol concentration was from 1.0 x 10(-6) to 1.0 x 10(-4) mol L(-1), with a detection limit of 4.0 x 10(-7) mol L(-1) (signal-to-noise ratio, S/N=3). In comparison with the 4-aminoantipyrine (4-AAP) standard method and the 3-methyl-2-benzothiazoline hydrazone (MBTH) method the proposed method can be used to detect many para-substituted phenols that do not react with 4-AAP and MBTH, and response factors are higher for most of the phenols tested. The method, which is simple, economic, and rapid (180 samples h(-1)), has been applied to the analysis of four wastewater samples. The results obtained were compared with those from 4-AAP method. The recoveries obtained by adding phenol standards to samples ranged from 94.3 to 105.2% with a standard deviation of 3.6%.  相似文献   

15.
Application of high performance liquid chromatography coupled with electrochemical detection (HPLC/EC) to the analysis of phenolic priority pollutants was studied. This method is highly sensitive and selective. Under optimum experimental conditions, the detection limits range from 0.05 ng for phenol to 1.20 ng for pentachlorophenol. The method was successfully applied to the direct determination of trace phenols in industrial wastewaters.  相似文献   

16.
An aniline-based polymer was electrochemically prepared and applied as a new fiber coating for solid phase microextraction (SPME) of some priority phenols from water samples. The polyaniline (PANI) film was directly electrodeposited on the platinum wire surface in sulfuric acid solution using cyclic voltammetry (CV) technique. The efficiency of new coating was investigated using a laboratory-made SPME device and gas chromatography with flame ionization detection for the extraction of some phenols from the headspace of aqueous samples. The scanning electron microscopy (SEM) images showed the homogeneity and the porous surface structure of the film. The results obtained proved the ability of this polymer as a suitable SPME fiber coating for trapping the selected phenols. Influential parameters affecting the extraction process were optimized and an extraction time of 50 min at 50 °C gave maximum efficiency, when the aqueous sample was saturated with NaCl and adjusted at pH 2. This new coating can be prepared easily in a reproducible manner and it is rather inexpensive and stable against most of organic solvents. The PANI thickness can be precisely controlled by the number of CV cycles. At the optimum conditions, the R.S.D. for a double distilled water spiked with phenol and chlorophenols at ppb level were 4.8-17% (n = 3) and detection limits for the studied compounds were between 0.69 and 3.7 ng ml−1, except for phenol and 4-chlorophenol. The optimized method was successfully applied to some real-life water samples.  相似文献   

17.
A reverse-phase high-performance liquid chromatography procedure with gradient elution and electrochemical detection is described for the determination of phenolic compounds, including several priority pollutant chlorophenols, in sea-water and sediments. In addition, a method for concentrating phenols from sea-water was examined. A solid-phase extraction using a derivatized poly(styrene-divinylbenzene) copolymer is discussed. The recovery, repeatability and detection limits are shown. Electrochemical detection provided selectivity as well as sensitivity. Phenols at the ng/l level were detected. The method was applied to the analysis of the most important phenolic compounds in sea-water and marine sediments.  相似文献   

18.
A scheme for separation and detection of eleven priority phenols using capillary zone electrophoresis (CZE) coupled with amperometric detection is described. With a capillary of I.D. 50 μm and length 62.5 cm at 9 kV and an electrophoretic buffer of 20 mM CHES (pH 10.1), complete separation of the eleven compounds was achieved in less than 17 min. Amperometric detection was carried out using a carbon fiber microelectrode of diameter 9 μm inserted into the end of the detection capillary. Linearity over two orders of magnitude was generally obtained for the eleven priority phenols. With an electrode potential+1.10 V (vs. Ag/AgCl reference), the concentration limits of detection were in the sub-ppm (10?6 M) level. This method was successfully applied to analysis of priority phenols in industrial waste water.  相似文献   

19.
A reverse-phase high-performance liquid chromatography procedure with gradient elution and electrochemical detection is described for the determination of phenolic compounds, including several priority pollutant chlorophenols, in sea-water and sediments. In addition, a method for concentrating phenols from sea-water was examined. A solid-phase extraction using a derivatized poly(styrene-divinylbenzene) copolymer is discussed. The recovery, repeatability and detection limits are shown. Electrochemical detection provided selectivity as well as sensitivity. Phenols at the ng/l level were detected. The method was applied to the analysis of the most important phenolic compounds in sea-water and marine sediments. Received: 12 April 1996 / Revised: 30 October 1996 / Accepted: 28 November 1996  相似文献   

20.
Alkaline water was used for the microwave-assisted extraction of some priority pollutants of phenols in sediments, i.e. phenol (Ph), 2-chlorophenol (2CP), 2,4-dichlorophenol (2,4DCP), 4-chlorophenol (4CP), 4-dinitrophenol (4NP) and pentachlorophenol (PCP). This organic solvent-free extraction procedure was optimized by studying the parameters such as pH, volume of the alkaline water, extraction pressure and time. Under the optimized conditions, the recoveries of phenols were in the range of 80% to 110%. The extracts were then cleaned-up and concentrated by microcolumn solid phase extraction (SPE) and determined by gas chromatography-flame ionization detection system. The relative standard deviation of the overall-method for most phenol determinations was about 5.0% (n = 6). The proposed method, which needs little volume (1 mL) of ethanol for SPE, has been applied to determine these phenols in sediment samples, and the analytical results are in good agreement with those achieved by Soxhlet extraction.  相似文献   

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