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1.
建立了高效溶剂萃取(HPSE)-固相萃取(SPE)/气相色谱-质谱(GC-MS)测定大气颗粒物中16种多环芳烃(PAHs)和15种有机磷阻燃剂(OPFRs)的方法。以正己烷-二氯甲烷(1∶1,体积比)溶液为萃取溶剂,萃取液旋转蒸发浓缩后经Florisil固相萃取柱净化,PAHs和OPFRs的洗脱溶剂分别为10 mL正己烷-二氯甲烷(1∶1)和10 mL乙酸乙酯,洗脱液浓缩定容后进行GC-MS测定。16种PAHs和15种OPFRs的线性范围为0.001 ~ 2.0 μg/mL,相关系数(r2)均大于0.99;检出限(LOD,S/N = 3)分别为0.10 ~ 10.00 μg/L和2.59 ~ 75.00 μg/L,定量下限(LOQ,S/N = 10)分别为0.33 ~ 33.33 μg/L和8.63 ~ 250.00 μg/L;平均回收率分别为73.0% ~ 98.0%和69.3% ~ 111%,相对标准偏差(RSD)分别为3.7% ~ 13%和2.5% ~ 17%。该方法适用于大气颗粒物样品中多环芳烃和有机磷阻燃剂的测定。  相似文献   

2.
建立了微波辅助萃取-气相色谱-质谱联用测定大气可吸入颗粒物中痕量多环芳烃(PAHs)的分析方法,优化了萃取时间、溶剂用量、微波辐射功率等微波萃取条件,并与超声波萃取方法进行了对照研究。结果表明:除了苊、芴外,微波萃取方法的回收率在85%-130%之间;方法的检出限在0.002-0.016μg/m^3之间。通过实际样品中PAHs的分析表明,该法快速、溶剂用量小,满足痕量分析的要求。  相似文献   

3.
荧光熄灭法测定痕量砷(Ⅲ)   总被引:1,自引:0,他引:1  
吴芳英  黄坚锋 《分析化学》1998,26(11):1404-1404
1 引 言砷(Ⅲ)对生物体的影响较大,在人体代谢过程中易于某些部位累积,引起慢性中毒,已列为公害病之一,因此,痕量砷(Ⅲ)的测定意义重大。砷(Ⅲ)的测定多采用AAS法及ICP法。近年来建立了一些荧光分析方法。由于实际样品中的砷(Ⅲ)含量极低,测定时常要富集,给测定带来不便。本文首次报道了新试剂7-[(2,4-羟基-5-羧基苯)偶氮]-8-羟基奎啉-5-磺酸(简称DHCBAQS)与As(Ⅲ)反应的荧光性能,建立起测定痕量砷(Ⅲ)的新方法,该方法灵敏度高,选择性好,操作简便快速,无须富集,可直接测定…  相似文献   

4.
本文合成了一种新的革并座隆类显色试剂—2-[2′-(6-溴-苯并噻唑)-偶氮]-1,8-二羟基萘-3,6-二磺酸(简称Br-BTCA),并研究了其与钛的显色反应。在CTMAB存在下,钛与试剂形成稳定的络合物,其ε616=1.15×105L·mol-1·cm-1,组成为Ti(Ⅳ):R:=1:2:钛浓度在0~0.5mg/L范围内符合比尔定律,该方法灵敏度高,选择性好,并用于铝合金及硅铁试样中微量钛的测定  相似文献   

5.
偶氮氯膦pA褪色分光光度法测定铬(Ⅵ)   总被引:11,自引:0,他引:11  
1 引 言2-(4-氯-2-膦酸基苯偶氮)-7-(4-乙酰基苯偶氮)-l,8-二羟基-3,6-萘二磺酸(简称偶氮氯膦pA)是测定稀土金属及钯、铑等贵金属离子的灵敏显色剂。实验发现Cr2O_7~(2-)离子在酸性介质中能使偶氮氯膦pA氧化褪色,且褪色程度与Cr2O_7~(2-)的含量呈线性关系,由此建立了测定微量铬(Ⅵ)的分光光度新方法。该方法所用试剂种类少,且在水相中进行,因而简单快速。Cr2O_7~(2-)在0.04~l.20 mg/L范围内符合比尔定律,表观摩尔吸光系数ε550=3.33 ×10~5…  相似文献   

6.
王超  黄肇章  邢占磊  陈烨  于建钊  刘方  袁懋 《色谱》2019,37(2):239-245
建立了在线固相萃取-液相色谱直接测定水体中16种超痕量多环芳烃(PAHs)的方法。水样经高速离心后,加入适量甲醇,配制成40%(体积分数)甲醇水溶液,直接进样2 mL至在线固相萃取流路,进行萃取富集,再通过阀切换将洗脱的PAHs转移至分析流路进行分离检测。16种PAHs在各自范围内线性关系良好,相关系数均大于0.996;方法的检出限为0.14~12.50 ng/L,其中苯并[a]芘(B(a)P)的检出限为0.38 ng/L。实际水样在10、40和200 ng/L加标水平下的加标回收率为76.1%~134.9%,RSD为0.3%~16.6%。B(a)P在1 ng/L加标水平下的回收率为71.8%~92.7%,RSD为3.9%。结果表明,该方法操作简单,灵敏度高,溶剂消耗量少,可满足水样中PAHs,尤其是B(a)P的超痕量分析要求。  相似文献   

7.
本文研究新试剂10-(2-羧基苯偶氮)-9-菲酚(简称CAP的合成,测定试剂的高解常数。研究了试剂CAP与铈(Ⅳ)的显色反应。在表面活性剂OP存在下,光度法测定球墨铸铁中铈的含量,结果较满意。  相似文献   

8.
本文研究新试剂10-(2-羧基苯偶氮)-9-菲酚(简称CAP)的合成,测定试剂的离解常数。研究了试剂CAP与铈(Ⅳ)的显色反应。在表面活性剂OP存在下,光度法测定球墨铸铁中铈的含量,结果较满意。  相似文献   

9.
邱凤仙  姚成 《分析化学》2000,28(6):792-792
1引言目前已有多种光度分析用于试样中的小量和痕量铁的测定,作者观察到在酸性介质中,十二烷基磺酸钠(NaLS)存在下可使4-(2-吡啶偶氮)-邻苯二酚[简称PAPC]与Fe(Ⅲ)的反应灵敏度提高,选择性增强,对比度高达123nm,从而建立了测定铁(Ⅲ)的新方法。2实验部分2.1主要仪器及试剂TU-1201型紫外分光光度计,722型分光光度计,铁标准溶液:10mg/L的标准溶液,PAPC(自制):1.0×10-3mol/L,十二烷基磺酸钠(NaLS):1%水溶液,HAc-NaAc缓冲溶液:pH=4.0,其它试剂均为AR级。2.2实验方法吸取一定量的铁标准溶液于2…  相似文献   

10.
用八羰基合二钴在相转移催化条件下合成1—萘乙酸   总被引:1,自引:0,他引:1  
戴金水 《应用化学》1998,15(1):86-87
1一荣乙酸是一种植物生长调节剂,也是合成茶乙酸甲酯(另一种优良的植物生长调节剂)的原料.其合成方法有多种“’“.本文研究了在常压下,利用CO。(CO)s在相转移催化条件下,使1一氯甲基素和一氧化碳直接反应,转化为帮乙酸的合成方法,气相色谱分析法研究了反应温度、催化剂用量等反应条件对转化率的影响.SP-3410型气相色谱仪(北京分析仪器厂),岛津IR-44O红外光谱仪(日本),EM-36060MHZ核磁共振仪(上海),HP5890-5971色谱一质谱联用仪(美国).l一氯甲基素(按文献[3」制备,纯度95%),八谈基合二钻(AR),…  相似文献   

11.
An analytical protocol including solid-phase extraction and purification is described for the individual quantification of polycyclic aromatic hydrocarbon metabolites (hydroxylated PAHs) in liquid biological matrices such as plasma and bile. The method consists in an enzymatic deconjugation followed by a solid-phase extraction on a C18 cartridge and by a cleanup on an NH2 cartridge. Extracts are then submitted to a derivatization step before gas chromatography/mass spectrometry (GC/MS) analysis. The quantification of PAH metabolites is ensured by adding an internal standard, 1-hydroxypyrene deuterated, at the beginning of the protocol. Recoveries obtained for the entire protocol were for the major part of the compounds between 96 and 70%. However, recoveries were not so satisfying concerning 2-hydroxybiphenyl and especially 3-hydroxybenzo(a)pyrene, with 62 and 36% respectively. Finally, the protocol was applied to different fish bile samples and showed its good applicability to fish bile samples. The NH2 cleanup step has been proved to be a very selective purification step, necessary to remove most of the bile pigments before GC/MS injection. Different PAH metabolites could be detected in those natural samples and their quantification allowed us to distinguish different levels of fish exposure.  相似文献   

12.
The use of micellar media in constant-energy synchronous fluorescence spectrometry has been proposed. The influence of some aqueous micellar systems on the determination of pyrene, perylene and benzo[a]pyrene has been investigated. The presence of these micellar systems allows their determination in aqueous media, thus avoiding the use of an organic solvent, and greatly enhances the fluorescence signals. The combination of a constant-energy synchronous scanning technique and a micellar system provided a single spectrum for the simultaneous identification and quantitative determination of the three polycyclic aromatic hydrocarbons (PAHs). Further there was no energy transfer among them, making the measurement simple and fast. A constant-energy difference of 2800 cm(-1) was selected. The analytical characteristics of the proposed method in the presence of anionic micelles of sodium dodecylsulfate (SDS) were studied. The detection limits were at a level of ng ml(-1). Analysis of water samples from two different origins spiked with known amount of pyrene, perylene and benzo[a]pyrene also gave satisfactory results, and total average recoveries were greater than 97.1%.  相似文献   

13.
A method capable of determining 13 PAHs (acenaphthene, anthracene, benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, chrysene, dibenzo[ah]anthracene, fluoranthene, fluorene, indene[1,2,3-cd]pyrene, phenanthrene and pyrene) in a mixture of 16 EPA PAHs by second derivative synchronous spectrofluorometry in the constant wavelength mode was developed. It has not been possible to determine the following PAHs in the mixture: acenaphthylene, benzo[ghi]perylene and naphthalene. The approach studied allows the sensitive, rapid and inexpensive identification and quantitation of 13 PAHs in a solution of hexane. The detection limits are <1 microg L(-1) (except for chrysene and phenanthrene).  相似文献   

14.
An automated extractor-concentrator was used to extract metabolites of naphthalene, 2,6-dimethylnaphthalene, and benzo[a]pyrene from serum, bile and liver homogenate of rainbow trout (Salmo gairdneri). The extracts were analyzed by reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection. Recoveries of naphthalene and 2,6-dimethylnaphthalene metabolites from all matrices were generally greater than 90%; however, the recoveries of benzo[a]pyrene metabolites from serum ranged from 37-99%. In addition, conjugated metabolites of polycyclic aromatic hydrocarbons (PAHs) were separated from non-conjugated metabolites and parent PAHs by using two diol columns with normal-phase HPLC. The extraction and separation techniques were also applied to isolate metabolites in samples from fish fed 2,6-dimethylnaphthalene.  相似文献   

15.
A simple and rapid method for the highly sensitive determination of polycyclic aromatic hydrocarbons (PAHs) in water was developed. Benzo[a]pyrene, benzo[k]fluoranthene, perylene, and pyrene in water were concentrated into sodium dodecyl sulfate (SDS)-alumina admicelles. The collection was performed by adding SDS and alumina particles into the sample solution at pH 2. After gentle mixing, the resulting suspension was passed through a membrane filter to collect the SDS admicelles containing highly concentrated PAHs. The filter was placed on a slide glass and then covered admicellar layer with a fused silica glass plate before setting in a fluorescence spectrometer. Benzo[a]pyrene, benzo[k]fluoranthene, perylene, and pyrene were selectively determined by the synchronous fluorescence scan (SFS) analysis with keeping wavelength intervals between excitation and emission to 98, 35, 29, and 45 nm, respectively. Because of the minimum spectral overlapping, 1-40 ng l−1 of benzo[a]pyrene, benzo[k]fluoranthene, and perylene as well as 10-150 ng l−1 of pyrene were selectively determined with eliminating the interferences of other 12 PAHs. The detection limits were 0.3 ng l−1 for benzo[a]pyrene, benzo[k]fluoranthene, and perylene, and 1 ng l−1 for pyrene. They were 2-3 orders of magnitude lower than the detection limits in normal aqueous micellar solutions. The application to water analysis was studied.  相似文献   

16.
The formation of polycyclic aromatic hydrocarbons (PAHs) during pyrolysis process of phenylalanine had been studied. Ten PAHs, including fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[k]fluoranthene, benzo[e]pyrene, and benzo[a]pyrene were analyzed by gas chromatography-mass spectrometry using selective ion monitoring mode. This technique offers the capability to analyze trace amounts of PAHs in phenylalanine pyrolyzates. The pyrolysis was carried out in a micro-furnace with quartz furnace liner. The injection was conducted with glass pelletizer syringe to avoid metal contamination. Qualitative results were obtained at 900 degrees C and quantitative analysis of 10 PAHs was done for 700 and 900 degrees C.  相似文献   

17.
采用超声波萃取大气飘尘样品中的多环芳烃,样品不需纯化,直接可用于同步荧光分析,超声波萃取效率高,萃取时间短;采用恒能量同步荧光法对多环芳烃进行定性定量,相关系数r>0.999 1,检出限(3δ)在0.013~4.4 ng之间,回收率为80%~132%。  相似文献   

18.
The analytical method of determining enzyme activity by liquid chromatography-mass spectrometry (LC/MS) was developed and applied for investigation of the effect of polycyclic aromatic hydrocarbons (PAHs) on the enzyme activity of chitinase. The measurement of chitinase activity by LC/MS is useful in order to use the nonderivatized substrate, which can show in vivo chitinase activity. Substrate consumption and product formation were monitored in order to determine chitinase activity. It was shown that, for the first time, in vitro addition of PAHs inhibited the activity of chitinase in a noncompetitive manner. The IC50 value of benzo[a]pyrene was 1.4 μM, and PAHs containing four or more aromatic rings showed the same or higher inhibitory effect, whereas PAHs with a lower number of aromatic rings showed lower inhibition of the chitinase activity than benzo[a]pyrene.  相似文献   

19.
A gas chromatographic (GC) method with mass spectrometry detection (MS) for the determination of eight polycyclic aromatic hydrocarbons (PAHs) in olive pomace oil has been developed. The oil was diluted with n-pentane and extracted by liquid-liquid partition with dimethyl sulphoxide (DMSO). After water addition and back-extraction with cyclohexane, a thin-layer chromatography on silica gel was performed as a further purification step. The PAHs spot was scraped off from the plate and the final extract was concentrated and analysed by GC-MS in full scan mode. The eight PAHs under investigation were determined in the presence of the corresponding labelled compounds added as internal standards to the sample at the beginning of the analytical process. The identified PAHs were then quantified by the isotope dilution methodology assuring the compensation of the concentration of each analyte for any variation in the sample preparation. The method precision was satisfactory with relative standard deviation (R.S.D.) values in the range 3.6-12.7% for all PAHs. The average recovery rates ranged from 69.0 to 97.5%. Accuracy was also calculated for benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene and benzo[ghi]perylene by analysing a certified reference material (CRM 458, coconut oil) with adequate results. All response curves exhibited a linear fit from 0.1 to 10 microg ml(-1) and the determination coefficients R2 were better than 0.9942. The limits of detection (0.1-0.4 microg kg(-1)) were acceptable when compared with the maximum permitted limit of 2 microg kg(-1) for each of the eight considered PAHs and 5 microg kg(-1) for the sum of the eight PAHs established by the Italian legislation. Measurement uncertainty was finally calculated identifying and quantifying the uncertainty components of the analytical process. The relative expanded uncertainties (Uc), expressed as percent values were in the range 8.5-11.4% thus appropriate for residues quantification in the range of concentrations considered in the present study.  相似文献   

20.
Summary The application of different non-ionic surfactants for the micellar extraction and enrichment of PAHs from aqueous media was tested. Recoveries were up to 100%. A spectroscopic method for the simultaneous detection of PAH-mixtures by synchronous fluorescence in the micellar phase was developed, with detection limits of 6.8 and 2.6 ng/l for benzo(k)fluoranthene and benzo(a)pyrene, respectively. The method was applied to the extraction and detection of benzo(k)fluoranthene/benzo(a)pyrene mixtures from aqueous solutions and soil suspensions. Genapol X-80 was found to suppress PAH-adsorption on bentonite at surfactant concentrations above 0.1%.Dedicated to Prof. Dr. V. Krivan on the occasion of his 60th birthday.  相似文献   

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