脉冲激光溅射合成全氯代多环芳烃

受Ｋｒａｔｓｃｈｅｒ等［１］电弧法合成Ｃ６０工作的启发,本课题组近年来以独创的液相电弧、微波放电等方法,合成了Ｃ５０及其多种全氯代碎片［２－５］．本文通过我们最近发展的脉冲激光溅射方法在四氯化碳的蒸汽中溅射石墨,得到丰富的克量级产物．这些产物经ＨＰＬＣ－ＵＶ－ＭＳ联用技术,表征为全氯代多环芳烃．其中部分物质含有五元环,可以看作是富勒烯形成过程中产生的全氯代碎片,该研究结果不仅有助于了解富勒烯的形成机理,而且展示了激光溅射合成法应用前景．１实验部分 实验在特制的反应装置上进行,所用的脉冲激光为Ｑ－…     

大气压化学电离-高分辨质谱直接分析食用油中的甘油三酯

建立了食用油中甘油三酯的大气压化学电离-质谱直接分析检测方法.在考察实验条件影响的基础上,选择乙腈作为溶剂,正离子检测模式,进样流速为800 μL/h,喷雾器温度250℃,电晕针电流为5000 nA.用本方法对10种食用油进行分析,结果表明,植物油与动物油之间差异较大.经主成分分析,选择m/z 857.76与m/z 881.76峰强度比作为指标,重复性RSD＜5％,可直接识别出玉米油中掺杂5％的猪油.用碰撞诱导解离(CID)实验初步鉴别了食用油的3个特征峰.利用本方法对泔水油样品和煎炸油样品进行分析,结果泔水油样品中含有植物油和动物油,而煎炸油样品也与商品食用油存在差异.本方法可用于食用油样品的快速筛查.     

二烷基二硫代磷酸锌的大气压化学电离质谱

采用大气压化学电离质谱技术（APCI－MS）对润滑油抗氧抗腐蚀添加剂丁基、辛基混合烷基硫代磷酸锌进行了分析，并结合APCI－MS技术中特有的源内化学电离检测（CID）功能对二辛基二硫代磷酸锌进行了结构表征；该法简便、快速，与传统方法相比有优越之处。     

高效液相色谱/大气压化学电离质谱分析新型复合抗氧剂

 应用高效液相色谱 /大气压化学电离质谱技术 ,其中包括直接进样技术、同时正负离子扫描方式、可编程的源内碰撞诱导解离 (CID)技术 ,以及红外光谱分析技术 ,对一种用于润滑油的新型复合抗氧剂进行了分离分析 ,并对其中的有效组分进行了定性鉴定。该方法简便、快速、可靠。     

月腺大戟中二萜类化学成分的大气压化学电离-串联质谱研究

利用大气压化学电离源多级串联质谱(APCI/MSn)方法对月腺大戟中的松香烷型二萜类成分,以及苯乙酮类成分进行了分析鉴定。根据串联质谱数据,共鉴定出7个化合物,分别为岩大戟内酯B、对映体-11α-羟基松香烷-8(14),13(15)-二烯-16,12α-内酯、岩大戟内酯A、月腺大戟甲素、月腺大戟乙素、狼毒乙素、3,3′-二乙酰基-4,4′-二甲氧基-2,2′,6,6′-四羟基二苯甲烷,并获得了相应化合物的结构信息。该方法可简便、快速鉴定月腺大戟有效成分。     

高效液相色谱/大气压化学电离质谱分析银杏叶中聚戊烯醇化合物

采用高效液相色谱，大气压化学电离质谱法(HPLC/APCIMS)分析银杏叶中聚戊烯醇化合物。在ODS-3柱上，以异丙醇-甲醇-正己烷-水(50：25：15：2，V/V)为流动相分离银杏叶中不同碳链长度的聚戊烯醇，通过质谱分析对每种聚戊烯醇化合物进行定性鉴定，外标法定量分析各聚戊烯醇含量。经HPLC/APCIMS分析，银杏叶中含有C75-C105聚戊烯醇，其中主要为C85、C90和C95聚戊烯醇。该方法简便，快速。     

电喷雾飞行时间质谱与大气压化学电离质谱法分析烟叶中茄尼醇的比较

采用反相高效液相色谱(RP-HPLC-UV)和电喷雾飞行时间质谱(ESI-TOF/MS)、大气压化学电离质谱(APCI-MS),分析烟叶中的茄尼醇.使用反相G4色谱柱,以V(甲醇):V(水)=9:1为流动相,茄尼醇和烟草中的其它成分分离良好;茄尼醇在ESI正离子全范围扫描中主要形成[M-H2O H] 和[M NH4] 离子,只有微弱的[M H] 离子,同时会产生一些碎片离子;而在APCI正离子全范围扫描中主要形成[M-H2O H] 离子,检测不到[M H] 离子,碎片离子也很少;通过对茄尼醇的ESI-TOF/MS和APCI-MS的质谱分析特征比较可以发现,茄尼醇在ESI源分析中的信号强度远远小于在APCI源分析中的信号强度,说明APCI源更适于茄尼醇的定量分析.     

分散固相萃取-气相色谱-串联质谱法测定蔬菜中多环芳烃及卤代多环芳烃

建立了同时检测蔬菜中16种多环芳烃(PAHs)和11种卤代多环芳烃(X-PAHs)污染水平的分散固相萃取-气相色谱-串联质谱(GC-MS/MS)分析方法。样品中的多环芳烃和卤代多环芳烃经正己烷提取,N-丙基乙二胺吸附剂(PSA)和十八烷基键合硅胶吸附剂(C18)分散固相萃取净化剂净化,气相色谱-串联质谱方法测定,外标法定量。16种PAHs和11种X-PAHs在50,100和200μg/kg添加浓度下的回收率为74.7%～115.1%,相对标准偏差为1.6%～15.3%,方法检出限为0.03～7.4μg/kg。     

在线气体分析的电晕放电大气压电离质谱

研制了适合在线气体分析的电晕放电大气压电离源(corona discharge atmospheric pressure ionization source)及其与商品质谱仪(LTQ-MS)的接口,对其试剂离子的产生机理进行了研究,以H2O. (H2O)为试剂离子,对乙醇气体进行检测,并分析了该离子的产生机制。实验结果表明:在潮湿氮气中电晕放电产生的主要试剂离子是m/z36、37和55;而在含丙酮的潮湿氮气中则产生m/z59和76等离子。利用静态顶空-电晕放电大气压电离质谱对不同浓度的乙醇水溶液进行分析,结果表明:以m/z64为检测对象,乙醇气体浓度的最低检出限可达2.4×10-7g/L;而以m/z47为检测对象,检出限为5.9×10-6g/L。同时还利用动态顶空-电晕放电大气压电离质谱对栀子花香气成分进行了检测,为生物挥发性物质的在线检测提供了一种新方法。     

凝固漂浮有机液滴-分散液液微萃取结合高效液相色谱法同时测定自来水中氯代多环芳烃与多环芳烃

建立了自来水中6种氯代多环芳烃和15种多环芳烃的凝固漂浮有机液滴-分散液液微萃取高效液相色谱分析方法,并探讨了萃取剂种类和用量、分散剂种类和用量、氯化钠含量及涡旋振荡时间等因素对萃取效率的影响。优化后的萃取实验条件为:10μL十二醇为萃取溶剂,500μL甲醇为分散溶剂,6%NaCl,涡旋振荡时间2 min。目标化合物经多环芳烃专用柱(SUPELCOSILTMLC-PAH,150 mm×4.6 mm,5μm)分离后,外标法定量。结果表明,21种目标化合物在一定质量浓度范围内线性良好,相关系数均不低于0.999;在低、中、高3个加标水平下的回收率为70.6%～98.7%,相对标准偏差(RSD)为2.0%～10%;方法的检出限(LOD,S/N=3)为0.000 7～0.009μg/L,定量下限(LOQ,S/N=10)为0.002 2～0.028μg/L。可用于自来水中氯代多环芳烃和多环芳烃的分析检测。     

Determination of oxygen and nitrogen derivatives of polycyclic aromatic hydrocarbons in fractions of asphalt mixtures using liquid chromatography coupled to mass spectrometry with atmospheric pressure chemical ionization

Liquid chromatography coupled to mass spectrometry with atmospheric pressure chemical ionization was used for the determination of polycyclic aromatic hydrocarbon derivatives, the oxygenated polycyclic aromatic hydrocarbons and nitrated polycyclic aromatic hydrocarbons, formed in asphalt fractions. Two different methods have been developed for the determination of five oxygenated and seven nitrated polycyclic aromatic hydrocarbons that are characterized by having two or more condensed aromatic rings and present mutagenic and carcinogenic properties. The parameters of the atmospheric pressure chemical ionization interface were optimized to obtain the highest possible sensitivity for all compounds. The detection limits of the methods ranged from 0.1 to 57.3 μg/L for nitrated and from 0.1 to 6.6 μg/L for oxygenated derivatives. The limits of quantification were in the range of 4.6–191 μg/L for nitrated and 0.3–8.9 μg/L for oxygenated derivatives. The methods were validated against a diesel particulate extract standard reference material (National Institute of Standards and Technology SRM 1975), and the obtained concentrations (two nitrated derivatives) agreed with the certified values. The methods were applied in the analysis of asphalt samples after their fractionation into asphaltenes and maltenes, according to American Society for Testing and Material D4124, where the maltenic fraction was further separated into its basic, acidic, and neutral parts following the method of Green. Only two nitrated derivatives were found in the asphalt sample, quinoline and 2‐nitrofluorene, with concentrations of 9.26 and 2146 mg/kg, respectively, whereas no oxygenated derivatives were detected.     

溴代稠环芳烃的氧化溴化法合成

以HBr/H2O2为溴化体系,采用氧化溴化法合成了6种稠环芳烃的溴化物。 合成反应无需催化剂,通过控制反应温度和溴化试剂用量,可以在稠环芳烃化合物的活性位选择性地单溴化或双溴化,产率可达51.1%～94.2%。 产品经熔点和1H NMR法确认,合成操作简单安全,环境污染少,有工业应用前景。     

羟基取代的多环芳烃与一氧化氮的反应研究

内源性的一氧化氮(NO)是多种生理过程中必不可少的信使分子,它在神经系统递质传导、神经发育、脑血流调节以及免疫调节等过程中具有十分重要的作用。为揭示NO生理功能的化学本质,NO成为化学家近年来研究的重要课题之一。     

Helical Ullazine-Quinoxaline-Based Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic azomethine ylides (PAMYs) are powerful building blocks in the bottom-up synthesis of internally nitrogen-containing polycyclic aromatic hydrocarbons (N-PAHs) through 1,3-cycloaddition reactions. In this work, the cycloaddition reaction of PAMYs to asymmetric ortho-quinones is presented, which, in contrast to the addition to symmetric para-quinones, facilitates subsequent condensation reactions and allows the synthesis of three helical N-PAHs with ullazine-quinoxaline ( UQ - 1 – 3 ) backbones. UQ - 1 and UQ - 2 possess two helical centers; however, single-crystal X-ray analysis together with the computational modeling of UQ - 3 elucidate the formation of only the thermodynamically most stable geometry with four helical centers in a (P,P,M,M) configuration. For the series UQ - 1 – 3 , the number of redox steps is directly correlated with the number of ullazine or quinoxaline units incorporated into the targeted molecular backbones. A detailed investigation of the spectroscopic and magnetic properties of the radical cation and anion as well as the dication and dianion species by in situ EPR/UV/Vis-NIR spectroelectrochemistry is provided. The excellent optical and redox properties combined with helical geometries render them possibly applicable as chiral emitter or ambipolar charge transport material in organic electronics.     

Relationship between the Biodegradability and Structure of Polycyclic Aromatic Hydrocarbons

21 Physicochemical and quantum chemical parameters of 17 kinds of polycyclic aromatic hydrocarbons were calculated by using semi-empirical MOPAC AM1 method. By means of Partial Least Squares （PLS）, quantitative structure-biodegradation relationship （QSBR） study was performed with the logarithm of specific biodegradation rates （logKb）. The optimal model was obtained, and the result showed that the first-order molecular connectivity index （^1X）, the energy of the lowest unoccupied molecular orbital （Elumo）, logarithm of n-octyl alcohol/water partition coefficient （logP） and torsion energy （Et） are the dominant factors governing the biodegradability of polyeyelie aromatic hydrocarbons, and the effect of second-order valence molecular connectivity index （^2X^V）, the third-order valence molecular connectivity index （^3X^V） and molar refractivity （Rm） should not be ignored.     

气相色谱/质谱法测定熏肉中的多环芳烃

建立了熏肉中多环芳烃的气相色谱/质谱(GC/MS)测定方法。样品经正己烷-丙酮(体积比为1∶1)超声波提取、氧化铝柱净化后,用GC/MS分离测定。优化了25种多环芳烃(PAHs)化合物的分离测定条件。结果 25种PAHs回收率范围为48.5%-106.5%;日内(n=7)相对标准偏差为3.75%-7.95%。方法具有灵敏度高、准确度好、能同时分离测定20余种多环芳烃化合物的优点,适合于熏肉中多环芳烃化合物的分析测定。     

Polycyclic Aromatic Hydrocarbons Formation from Fuel and Additives Combustion

A study has been made of the effect of additives to the fuel of a turbulent diffusion flame on the formation of soot and polycyclic aromatic hydrocarbons (PAHs). Fuels containing a polystyrene thickener doped with benzene proved to have many advantages over unthickened fuels. Most significant were an increase in the burning time and the flash point. Nevertheless, polystyrene and benzene additives to a considerable extent increased the formation of soot and PAHs. The analysis of PAHs in this study was made by capillary gas chromatography (GC) and capillary gas chromatography/mass spectrometry (GC/MS). A total of 42 individual compounds were characterized by their retention indices and mass spectra.     

Analysis of Isomeric Alkylated Polycyclic Aromatic Hydrocarbons by Matrix Isolation Fourier Transform Infrared Spectroscopy

Abstract

Matrix isolation Fourier transform infrared spectra of isomeric methylnaphthalenes and methylbiphenyls, in N₂ matrices at 15 K, are compared with each other and with those of the respective parent hydrocarbons. The applicability of matrix isolation Fourier transform infrared spectroscopy to both identification and quantitative analysis of individual alkylated polycyclic aromatic hydrocarbon isomers in mixtures is demonstrated.