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1.
蒙旦树脂烃化学组成及结构特征   总被引:9,自引:2,他引:7  
本文对中国三种蒙旦树脂烃潦浒树脂烃(LHT),寻甸树脂烃(XDT),舒兰树脂烃(SLT)进行了GCMS分析,获取了树脂烃中单元化合物的组成和结构。结果表明,在这三种树脂烃中,主要是五环三萜烃类五环三萜烷,五环三萜烯,单环、二环、三环、四环芳构化五环三萜烷以及三环二萜烃类降松脂烷,降松香烷,降海松烷,松香烷,山达松脂烷,单环、二环芳构化三环萜烷。比较三种树脂的总离子色谱图,发现在寻甸蒙旦树脂烃和舒兰树脂烃中,五环二萜的各种化合物是该组分主要化学组成,尤其在舒兰蒙旦树脂烃中,具有四环芳构化的萜烷其含量占绝对优势。潦浒蒙旦树脂烃中,三环二萜的各种物质是其重要的化学组成。与此同时,阐述了中国蒙旦蜡精制漂白脱色不完全的原因。  相似文献   

2.
本文研究云南宝秀盆地一个钻孔不同深度的泥炭和褐煤抽出物芳烃馏分中多环芳烃的组成。用GC和GC/MS鉴别了它们的组份,结果表明,从双环和三环单芳构化、双芳构化、三芳构化到四环双芳构化、三芳构化及四芳构化和五环单、双芳构化、三芳构化、四芳构化以及C环开裂的萜类化合物均有不同含量的存在,这说明在煤化过程早期芳构化就进行到相当的深度,也说明云南陆源高等植物,尤其是喜温树类的造煤物种为宝秀盆地提供了特殊的芳构化有机组成系列。  相似文献   

3.
多环芳烃的超临界流体色谱分离研究   总被引:6,自引:0,他引:6  
孙云鹏  孙传经 《色谱》1995,13(5):398-399
烃中多环芳烃(晕苯和卵苯)的分离是极其困难的。研究了在不同极性毛细管填充SFC柱上多环芳烃的分离条件。选用国产150mmCN填充柱,CO_2为流动相,线性升压,FID检测,可在26min内将烃中三到十环多环芳烃分离,定量重复性良好。  相似文献   

4.
与新鲜Mo/HZSM-5(F)催化剂相比,于973K以甲烷活化后的Mo/HZSM-5(A)对丙烷芳构化的活性和芳烃选择性都得到显著提高,芳烃的收率从3.35%提高到13.82%,根据催化剂(F)用于甲烷芳构化时存在活性诱导期,结合本实验的丙烷芳构化结果及XRD结果,提出担载于分子筛表面的MoO3经甲烷活化后转化为α-Mo2C后才对烷烃芳构化有较高活性。碳化钼是活性相,它的作用不在于活化烷烃,而是为  相似文献   

5.
C_(60)键合硅胶液相色谱固定相的合成及其性能评价   总被引:3,自引:1,他引:3  
刘英  达世禄  陈远荫 《色谱》1998,16(2):115-117
 以γ-(乙二胺基)丙基三乙氧基硅烷为偶联剂合成了C60键合硅胶固定相;用元素分析法测定得到该固定相的C60键合量为57.57μmol/g。考察了多环芳烃和杯芳烃在C60键合硅胶固定相上的分离,多环芳烃在该固定相上的洗脱顺序与ODS固定相相似;杯芳烃的洗脱顺序为杯[8]、杯[4]和杯[6]芳烃。  相似文献   

6.
C_(60)键合硅胶液相色谱固定相的合成及其性能评价   总被引:2,自引:0,他引:2  
以γ-(乙二胺基)丙基三乙氧基硅烷为偶联剂合成了C60键合硅胶固定相;用元素分析法测定得到该固定相的C60键合量为57.57μmol/g。考察了多环芳烃和杯芳烃在C60键合硅胶固定相上的分离,多环芳烃在该固定相上的洗脱顺序与ODS固定相相似;杯芳烃的洗脱顺序为杯[8]、杯[4]和杯[6]芳烃。  相似文献   

7.
潘海祥  麦碧娴 《分析化学》1999,27(2):140-144
参照美国EPA525.1方法,C18-固相萃取膜萃取饮用水中的有机物,利用GC/MS法鉴定多环芳烃(PAHS),使用16种多环芳烃混合标准样绘制标准曲线,以内标法对PAHS进行定量分析。采用本方法某水厂经过深度处理后的出厂水中的7种多环芳烃的含量,PAHS的平均回收率为94.0-97.7%。检测限为0.001μg/L。  相似文献   

8.
ZnHZSM-5上脱氢环化芳构化过程的探讨   总被引:1,自引:0,他引:1  
以正己烷、环己烷、甲基环戊烷、1-己烯和环己烯等分子探针反应,考察了单B酸型HZSM-5、Zn-L酸型ZnNaZSM-5和双中心型ZnHZSM-5(B酸和Zn-L酸)催化剂的性能,探讨了B酸中心和Zn-L酸中心在芳构化过程中的作用.实验结果表明,B酸中心有利于环化,L酸中心有利于脱氢芳构化.单具B酸或Zn-L酸中心催化剂上,直链烃分子的芳构化性能较差,当两种中心同时存在时,双功能互相促进,加快芳构化过程.文中还对C6分子脱氢环化芳构化过程进行了讨论  相似文献   

9.
超临界流体分级萃取正构烷烃和多环芳烃   总被引:10,自引:0,他引:10  
本工作用超临界CO2对环境模拟样品中的正构烷烃和多环芳烃的超临界分级萃取方法及超临界CO2的压力,温度和用量对分级效率的影响进行了详细的研究。结果表明,在低压、低温下(80MPa,50℃)能成功地分级萃取正构烷烃和多环芳烃,其C10~C18的萃取率为99.94%~59.28%,而多环芳烃基本未被萃取。当压力升至26.0MPa、温度升至80℃时,可有效地萃取多环芳烃,实现了正构烷烃和多环芳烃的有效分离  相似文献   

10.
杯芳烃固定液分子识别的热力学性质   总被引:3,自引:0,他引:3  
用毛细管气相色谱法测得了5组芳香族位置异构体在杯芳冠醚聚硅氧烷(C[4]C5_PSO),二乙氧基杯芳烃聚硅氧烷(C[4]E_PSO)和二丁氧基杯芳烃聚硅氧烷(M_C[4]B_PSO)3种杯芳烃固定液上的热力学参数ΔH、ΔS、ΔG,然后用热力学及超热力学的方法探讨了杯芳烃对异构体的分子识别特性和保留机理。  相似文献   

11.
SRM 1597 Complex Mixture of Polycyclic Aromatic Hydrocarbons from Coal Tar, originally issued in 1987, was recently reanalyzed and reissued as SRM 1597a with 34 certified, 46 reference, and 12 information concentrations (as mass fractions) for polycyclic aromatic hydrocarbons (PAHs) and polycyclic aromatic sulfur heterocycles (PASHs) including methyl-substituted PAHs and PASHs. The certified and reference concentrations (as mass fractions) were based on results of analyses of the coal tar material using multiple analytical techniques including gas chromatography/mass spectrometry on four different stationary phases and reversed-phase liquid chromatography. SRM 1597a is currently the most extensively characterized SRM for PAHs and PASHs.  相似文献   

12.
北京地区大气颗粒物中不同功能区多环芳烃的分布特征   总被引:1,自引:0,他引:1  
用撞击式分级采样器同步采集了北京市城乡结合部、郊区的2003年四个季节的不同粒径大气颗粒物样品,用气相色谱-质谱分析了其中的多环芳烃。两个功能区的PAHs总质量浓度分布趋势均为:冬季>秋季>春季>夏季;不同环数PAHs在不同粒径颗粒物中的分配比例比较显示,粗颗粒物中2 环或3环PAHs的分配比例比其在高环PAHs的比例要大。  相似文献   

13.
宋春侠  王威  刘泽龙  刘颖荣  蔡新恒 《色谱》2019,37(7):750-758
基于氯化钯配位交换色谱柱和氨基键合正相色谱柱,利用自动阀切换系统,构建了在线二维液相色谱分离平台。通过优化液相色谱分离条件,实现减压蜡油样品中含硫芳烃的在线富集与多环芳烃的环数分离。利用傅里叶变换离子回旋共振质谱对分离后的含硫芳烃和芳烃组分进行分子水平表征,得到更为详细的化合物类型与碳数分布信息。根据计算得到的平均结构信息,可以提供分离后组分典型的分子结构式,并对芳环结构和侧链位置进行了推测。建立的分析表征方法可以加深对重馏分油中含硫芳烃化合物的分子水平认识,为重油加工过程的原料选择与工艺条件优化提供技术支持。  相似文献   

14.
气相色谱质谱法测定化妆品中9种多环芳烃   总被引:1,自引:0,他引:1  
建立了气相色谱质谱法测定化妆品中9种多环芳烃的分析方法。化妆品中的萘、苯并[a]蒽、、苯并[b]荧蒽、苯并[j]荧蒽、苯并[k]荧蒽、苯并[e]芘、苯并[a]芘、二苯并[a,h]蒽等9种多环芳烃用甲醇超声提取后,用环己烷液-液萃取后浓缩,经硅胶-中性氧化铝柱净化后,采用气相色谱-质谱测定。多环芳烃浓度在0.05~2 mg/L范围内,质量浓度与其峰面积呈良好的线性关系。在低、中、高3个添加水平下,9种多环芳烃化合物的平均回收率为81.6%~100.2%,相对标准偏差为1.3%~5.8%。方法可用于化妆品中多环芳烃的检测。  相似文献   

15.
使用色谱-质谱联用中的选择离子监测的方法选择性地检测柴油机排气中的多环芳香烃,采用14种多环芳香烃混合标准样品绘制校正曲线,以外标法对柴油机排气微粒中的PAHs进行定量分析。实验结果表明,该方法能够减少其它类有机成份的干扰,快速、准确地测量柴油机排气微粒中多环芳香烃的含量,且重复性较好,相对标准偏差低于 12%(n=6),检出限为3.5~7.0pg/m3,样品的回收率为79%~89%,方法用于柴油机排气微粒中多环芳香烃排放量的测定取得了满意的效果。  相似文献   

16.
Aryl hydrocarbon receptor (AhR) agonistic contaminants were identified in roadside snow samples. Snow was collected in Oslo, Norway, and compared to a background sample collected from a mountain area. The water and particulate fractions were analysed for AhR agonists using a dioxin-responsive, chemically activated luciferase expression (CALUX) cell assay and by gas chromatography coupled to high-resolution time-of-flight mass spectrometry with targeted analysis for polycyclic aromatic hydrocarbons (PAHs) and broad-spectrum non-target analysis. The AhR agonist levels in the dissolved fractions in the roadside samples were between 15 and 387 pg/L CALUX toxic equivalents (TEQ(CALUX)). An elevated AhR activity of 221 pg TEQ(CALUX) per litre was detected in the mountain sample. In the particle-bound fractions, the TEQ(CALUX) was between 1,350 and 7,390 pg/L. One possible explanation for the elevated levels in the dissolved fraction of the mountain sample could be the presence of black carbon in the roadside samples, potentially adsorbing dioxin-like compounds and rendering them unavailable for AhR interaction. No polychlorinated dibenzodioxins and dibenzofurans or polychlorinated biphenyls were detected in the samples; the occurrence of PAHs, however, explained up to 9 % of the AhR agonist activity in the samples, whilst comprehensive two-dimensional gas chromatography coupled to mass spectrometry GCxGC-ToF-Ms identified PAH derivatives such as polycyclic aromatic ketones and alkylated, nitrogen sulphur and oxygen PAHs in the particle fractions. The (large) discrepancy between the total and explained activity highlights the fact that there are other as yet unidentified AhR agonists present in the environment.  相似文献   

17.
A simple and effective solid phase extraction (SPE) method using silica gel micro glass columns has been developed for the separation of diesel fuel into groups of aliphatic, and mono-, di- and polyaromatic hydrocarbons. It is based on a stepwise gradient of dichloromethane in n-pentane. The resulting fractions were analyzed by capillary gas chromatography with a flame ionization detector and coupled gas chromatography-mass spectrometry. Commercially available standards, and retention indices and mass spectra were used for identification of individual aromatic compounds. The principal polycyclic aromatic hydrocarbons (PAHs) in diesel fuel are naphthalene, biphenyl, fluorene, phen-anthrene and their alkylated derivatives. Sulfur-containing PAHs are mainly represented by methyl-substituted dibenzo-thiophenes.  相似文献   

18.
《Analytica chimica acta》2004,508(2):177-183
The objective of this study was to optimize and characterise extraction methods to examine the effects of wood ash application on polycyclic aromatic hydrocarbons (PAHs) concentrations in run-off waters for the evaluation of their distribution by storage in the different compartments (free and bound to dissolved organic matter, DOM), what influence their stability and persistence. The feasibility of solid phase extraction (SPE) and stir bar sorptive extraction (SBSE) for the determination of eight PAHs in run-off water samples has been evaluated. Both are appropriate to determine PAHs in run-off waters, but SPE is suitable for the determination of overall PAHs, while SBSE is used for the determination of free PAHs. The combination of both extraction techniques can then be used to estimate PAHs bound to DOM. Another approach based in the only use of SBSE is proposed for the estimation of all PAHs fractions (free, bound to DOM, and overall), once we are able to estimate the fraction percentage the free concentration represents. The percentage of free fraction was variable in the run-off waters with medium levels of DOM depending on the number of aromatic rings, molecular weight and water solubility of PAHs.  相似文献   

19.
A method is described for the determination of three- to six-ring polynuclear aromatic hydro-carbons (PAHs) and mononitrated PAHs (nitro-PAHs) in particulate matter. The procedure includes Soxhlet extraction followed by fractionation using gel filtration chromatography and normal-phase liquid chromatography with an aminosilane stationary phase. The resulting fractions were separated by capillary gas chromatography (GC) into individual PAHs and nitro-PAHs which were detected by a flame-ionization detector and a thermal energy analyzer, respectively. Commercially available standards were used for quantification. Individual peak assignments were confirmed by using both mass spectral and retention index data obtained through computerized capillary GC-mass spectrometry. Several samples were processed, including a certified diesel particulate reference material supplied by the National Bureau of Standards for the purpose of evaluating analytical methods. This method may also be applicable in the determination of certain carbonyl PAHs.  相似文献   

20.
By using the relationship equation of Partition coefficients with water solubilities for polycyclic aromatic hydrocarbons (PAHs), we have estimated the solubilities of PAHs. In addition the high-performance liquid chromatograph (HPLC) method has been used for the indirect determination of solubilities of PAHs. t3ased on the di-region theory, We have studied the relationship of the solubilities of PAHs with carcinogenicity and introduced the solubility parameter into the di-region theory equation. The calculated carcinogenicity of PAHs from the obtained equation shows little difference from that calculated from Dai Qianhuan's equation.  相似文献   

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