毛细管气相色谱法研究对环芳烷二氯化产物的组成

在选定毛细管柱温,载气流量、分流比、注入口和ＦＩＤ的温度等色谱条件下,分析了对环芳烷（ＰＣＰ）二氯化产物的组成。定性分析结果表明,ＰＣＰ二氯化产物除主要组分是二氯对环芳烷（ＤＣＰＣＰ）外,还含少量的一氯对环芳烷（ＭＣＰＣＰ）和三氯对环芳烷（ＴＣＰＣＰ）;ＤＣＰＣＰ的色谱图上出现了３个明显的色谱峰,证明３种异构体相对含量较高。用丙酮－石油醚混合溶剂分离去除 物得到了纯度为９９．１％的ＤＣＰＣＰ。以邻苯二甲酸二丁酯为内标物,测定了ＤＣＰＣＰ对内标物的相对质量校正因子。按内标法定量分析了ＰＣＰ二氯化产物各组分的含量,对ＤＣＰＣＰ分析的相对标准偏差小于３％。     

微波皂化萃取气相色谱法测定生物样品中的多氯联苯

１引言 多氯联苯（ＰＣＢｓ）的性质稳定、毒性大,贻贝等海洋生物能摄取和富集海水中的ＰＣＢｓ,因此研究其中ＰＣＢｓ的测定具有重要意义。生物样品中 ＰＣＢｓ的测定一般要进行预分离处理,索氏萃取分离 ＰＣＢｓ耗时至少８ｈ,加碱皂化生物组织再以液－液萃取提取ＰＣＢｓ需要在沸水浴中回流１～２ｈ,微波直接革取能有效地分离环境样品中的ＰＣＢｓ。本文利用微波皂化萃取（ＭＡＳＥ）气相色谱法（ＧＣ）测定生物样品中的多氯联苯,实验以未受ＰＣＢｓ污染的淡水鱼为空白,用正交试验系统优化了微波功率、微波加热时间、皂化及萃取溶…     

碱金属和稀土溴化物Meyer反应的相化学研究（I）

研究了四元体系ＣｓＢｒ－ＬａＢｒ３－ＨＢｒ（１２％）－Ｈ２Ｏ（２５℃）的相化学关系，绘制了相应的溶度图。在该体系中发现一种新型化合物５ＣｓＢｒ．２ＬａＢｒ３．２２Ｈ２Ｏ；对该人合物进行了偏光、Ｘ射线粉末衍射、ＴＧ及ＤＴＡ等方面的，将本体系与四元系ＣｓＣｌ－ＬａＣｌ３－ＨＣｌ（１３％）－Ｈ２Ｏ（２５℃）相比较，发现两者在生命化合物的数量、种类和相化学行为方面均有较大的差异。     

铜(Ⅱ)与苯基羧酸(HPCA)和2,2''''-联吡啶衍生物(dpx)混配配合物的合成和表征

合成了铜（Ⅱ）与苯基羧酸根［ＰＣＡ－＝苯甲酸根（Ｂｚ－），２－苯乙酸根（ＰＡｃ－），３－苯丙酸根（ＰＰｒ－），４－苯丁酸根［ＰＢｕ－）］和２，２′－联吡啶衍生物（ｄｐｘ：２，２′－联吡啶胺ｄｐａ、２，２′－联吡啶酮ｄｐｋ、２，２′－联吡啶甲烷ｄｐｍ）三大系列１２种新的三元配合物。用元素分析、摩尔电导、红外光谱、１Ｈ核磁共振、差热分析等实验方法表征了它们的组成和性质。确定该系列配合物化学组成为Ｃｕ（ＰＣＡ）２（ｄｐａ）、Ｃｕ（ＰＣＡ）２（ｄｐｍ）、Ｃｕ（ＰＣＡ）２（ｄｐｋ）·ｎＨ２Ｏ（ｎ＝２－４）。它们具有相似的组成和配位方式。它们的可能结构为：二个ＰＣＡ－与Ｃｕ（Ⅱ）单齿配位，一个ｄｐｘ与Ｃｕ（Ⅱ）Ｎ，Ｎ二齿螯合配位。ｄｐｋ的羰基在金属离子Ｃｕ２＋的存在下发生水化作用成ｄｐｋ·Ｈ２Ｏ。用１ＨＮＭＲ法研究了Ｃｕ（Ｂｚ）２（ｄｐｘ）·ｎＨ２Ｏ和Ｃｕ（ＰＡｃ）２（ｄｐｘ）·ｎＨ２Ｏ二个体系其分子内或分子间可能存在的非共价键作用。     

一种新的有机污染物采样装置

介绍了一种由类脂物和半透膜组成的采样装置,该装置可模拟生物监测可被生物订的有机污染物。将其用于监测大气、水体、沉积物中的多氯联苯（ＰＣＢｓ）、有机氯农药（ＯＣＰ）和多环芳烃（ＰＡＨｓ）时,结果满意。     

GC/MS分析环境样品中的多氯联苯(PCBs)

多氯联苯（ｐｏｌｙｃｈｌｏｒｉｎａｔｅｄ Ｂｉｐｈｅｎｙｌｓ,简称ＰＣＢｓ）系一组化学性质极其稳定的氯代烃类化合物,由于难降解,可通过食物链而富集且直接危害人类的健康,因此,这类化合物已成为全球性的重要污染物之一。利用圆盘型固相萃取－ＧＣ－ＭＳ测定水样中的ＰＣＢｓ,同时采剂超声萃取－ＧＣ－ＭＳ分析了各种土壤样品和植物样品中的ＰＣＢｓ,实验结果证明分析方法中样品前处理过程简单、方法回收较高,重现性好,然质联用能够测定ＰＣＢｓ的同系物。另外,由已有的数据可以看出,中国土壤中存在有一定量的ＰＣＢｓ,特别是在一些特定污染地区的土壤中ＰＣＢｓ的浓度较高,另外,由于土壤的污染还影响到水和植物的污染。     

CmI奇宇称光谱能级的模式识别研究

应用新的模式识别方法ＰＣＡ－ＢＰＮ（ＰｒｉｎｃｉｐａｌＣｏｍｐｏｎｅｎｔＡｎａｌｙｓｉｓ－ＢａｃｋＰｒｏｐａｇａｔｉｏｎＮｅｔｗｏｒｋ）指认ＣｍＩ奇宇称未知能级，支持了前人应用传统的ＫＮＮ（ＫＮｅａｒｅｓｔＮｅｉｇｈｂｏｒｓ）等模式识别方法及对传神经网络方法（ＣｏｕｎｔｅｒＰｒｏｐａｇａｔｉｏｎｎｅｔｗｏｒｋ，ＣＰＮ）对大部分谱线的指认，进一步确认了这些组态的归属，鉴别了ＫＮＮ等与ＣＰＮ不同的预报     

异戊二烯/甲基丙烯酸甲酯嵌段共聚物的合成与微结构研究

用稀土催化剂ＲＥ（Ｐ２０４）３ （ｉ Ｂｕ）３Ａｌ ＢｒＣＨ２ＣＨ２Ｂｒ（ＲＥ＝Ｎｄ,Ｐｒ,Ｙ等）合成嵌段共聚物Ｐ（ＩＰ ｂ ＭＭＡ）．系统考察了共聚合反应特征,以ＤＳＣ,１Ｈ ＮＭＲ,１３Ｃ ＮＭＲ技术研究了该嵌段共聚物的微结构．发现以二溴乙烷为添加剂的稀土催化体系是制备Ｐ（ＩＰ ｂ ＭＭＡ）的良好催化剂,共聚物含２个玻璃化转变温度,分别为－７５６℃和１２９℃,嵌段共聚物的结构规整,（ＩＰ）ｍ段以ｃｉｓ １,４结构为主,其含量为９７％左右,３,４ 结构为３％左右,链节间以头 尾方式连接．（ＭＭＡ）ｎ段以间同立构为主,其含量达７４％．     

不同操作模式下多环芳烃气相色谱特性的研究

在气相色谱分析萘、联苯、苊、芴、菲、蒽、荧蒽、芘、苯并（ａ）蒽、屈艹、苯并（ａ）芘和匹艹的研究过程中,以有效塔板数（ｎｅｆｆ）作为考察指标对新型色谱操作模式——程序升温升压操作条件进行了优化。通过对Ｋｏｖａｔｓ保留指数体系和Ｌｅｅ 保留指数体系在不同操作模式下的对比实验表明,在脉冲进样和程序升压等新型色谱操作条件下,Ｌｅｅ 保留指数体系仍能够满足对多环芳烃定性分析的要求, 前者则不能。     

化合物Cs3Dy2Br9合成机理的相化学研究

研究了ＣｓＢｒ与ＤｙＢｒ３在氢溴酸介质中反应的四元体系ＣｓＢｒ－ＤｙＢｒ３－ＨＢｒ（１３％）－Ｈ２Ｏ（２５℃）相化学关系，发现了新物相５：３型化合物５ＣｓＢｒ．３ＤｙＢｒ．２４Ｈ２Ｏ，并对其进行了Ｘ射线，ＤＴＧ，ＤＴＡ及偏光显镜等方面的研究。     

Characterization of three Aroclor mixtures using a new cyanobiphenyl stationary phase

The retention characteristics of all 209 polychlorinated biphenyl (PCB) congeners were determined on a new p,p-cyanobiphenyl stationary phase using gas chromatography with electron capture detection (GC-ECD). Response factors were determined relative to decachlorobiphenyl, PCB 209. Several congeners that coelute on the phases routinely used for PCB analysis are separated on this phase, including the hexachlorobiphenyls 138, 163, and 164. The p,p-cyanobiphenyl stationary phase exhibits altered retention for planar congeners, such that the toxic coplanar PCBs 77, 126, and 169 are eluted free from interference. Of the 209 congeners, 61 were separated using the p,p-cyanobiphenyl phase in conjunction with GC-ECD. When analyzed by gas chromatography with mass selective detection (GC-MSD), the number of congeners determined increased to 133. Therefore GC-MSD was used with the p,p-cyanobiphenyl phase to characterize three PCB mixtures: Aroclor 1242, Aroclor 1254, and Aroclor 1260.     

Application of a retention database to the identification of individual polychlorinated biphenyl congeners in Aroclors mixture using selected polychlorinated biphenyls as a reference series

The database of the relative retention times (RRTs) of polychlorinated biphenyls (PCBs) reported in literature was used to calculate the retention indices (RIs) of all 209 PCB congeners on temperature programmed capillary column Rtx-5. Calculation of retention indices was based on reference series of seven congeners (PCB IUPAC Nos. 18, 52, 101, 143, 185, 203 and 206) that exhibit linear relative retention time behaviour as a function of chlorine number. The calculated indices were compared to those determined in our laboratory as well as to those obtained by other authors. The proposed indices system was applied for identification individual congeners in mixture of Aroclors 1242:1254:1260, using only reference series of PCBs.     

Gas chromatographic separation of polychlorinated biphenyls on a new apolar capillary column

Eighty one polychlorinated biphenyls (PCBs) and nineteen chlorinated pesticide standards have been analyzed on a newly developed apolar high resolution gas chromatography (HRGC) column. Emphasis was placed on the determination of PCB indicator congeners which are part of national regulations, and of toxic coplanar PCB congeners. The new column enables almost unambiguous quantification of the PCB indicator congeners (PCB 138 can be separated from both PCB 163 and PCB 164; PCB 28 and PCB 31 were also separated and no coelution was observed for PCB 52, PCB 118, and PCB 180). The new column furnished better results than CP-Sil 8 for the analysis of PCB indicator congeners in a sample of seal blubber.     

Use of a polar ionic liquid as second column for the comprehensive two-dimensional GC separation of PCBs

The orthogonality of three columns coupled in two series was studied for the congener specific comprehensive two-dimensional GC separation of polychlorinated biphenyls (PCBs). A non-polar capillary column coated with poly(5%-phenyl–95%-methyl)siloxane was used as the first (¹D) column in both series. A polar capillary column coated with 70% cyanopropyl-polysilphenylene-siloxane or a capillary column coated with the ionic liquid 1,12-di(tripropylphosphonium)dodecane bis(trifluoromethane-sulfonyl)imide were used as the second (²D) columns. Nine multi-congener standard PCB solutions containing subsets of all native 209 PCBs, a mixture of 209 PCBs as well as Aroclor 1242 and 1260 formulations were used to study the orthogonality of both column series. Retention times of the corresponding PCB congeners on ¹D and ²D columns were used to construct retention time dependences (apex plots) for assessing orthogonality of both columns coupled in series. For a visual assessment of the peak density of PCBs congeners on a retention plane, 2D images were compared. The degree of orthogonality of both column series was, along the visual assessment of distribution of PCBs on the retention plane, evaluated also by Pearson's correlation coefficient, which was found by correlation of retention times t_R,i,2D and t_R,i,1D of corresponding PCB congeners on both column series. It was demonstrated that the apolar + ionic liquid column series is almost orthogonal both for the 2D separation of PCBs present in Aroclor 1242 and 1260 formulations as well as for the separation of all of 209 PCBs. All toxic, dioxin-like PCBs, with the exception of PCB 118 that overlaps with PCB 106, were resolved by the apolar/ionic liquid series while on the apolar/polar column series three toxic PCBs overlapped (105 + 127, 81 + 148 and 118 + 106).     

Reactivity features of polychlorobiphenyl congeners in the nucleophilic substitution reactions

Groups of congeners and individual congeners of polychlorobiphenyls contributing to the composition of the technical mixture “Sovol” (PCB 60, PCB 64, PCB 70, PCB 74, PCB 97, PCB 101, PCB 105, PCB 110, PCB 118, PCB 138, PCB 149, PCB 156, and PCB 163) were synthesized by the reaction of aryl-aryl coupling. The interaction of the congeners with sodium methoxide was performed and their complete conversion was proved. By means of gas chromatography-mass spectrometry the PCBs methoxy derivatives were identified. The data on the reactivity of the individual polychlorobiphenyl congeners were precised.     

Chiral comprehensive two-dimensional gas chromatography with electron-capture detection applied to the analysis of chiral polychlorinated biphenyls in food samples

The feasibility of comprehensive two-dimensional gas chromatography with electron-capture detection (GC x GC-ECD) for the enantioseparation of chiral PCBs from other possible interfering compounds has been evaluated. Three commercially available enantioselective beta-cyclodextrin-based capillary columns (Chirasil-Dex, BGB-172 and BGB-176SE) have been tested as first-dimension columns. Three non-enantioselective stationary phases (HT-8, BPX-50 and Supelcowax-10) were combined with the enantioselective columns to allow the unambiguous determination of the enantiomers of the target chiral PCBs. Each enantioselective first-dimension column tested was able to separate into enantiomers different PCB congeners, but in all cases, the use of Supelcowax-10 as second-dimension column provided the most satisfactory results. The Chirasil-Dex x Supelcowax-10 column combination allowed the determination of the enantiomeric fraction (EF) of PCBs 84, 91, 95, 132, 136, 149, 174 and 176 in the working standard solution, while that of congener 135 was hindered. The BGB-172 x Supelcowax-10 column set allowed a proper EF determination of congeners 45, 84, 131, 132, 135, 171, 174 and 183, while that of PCB 91 was interfered with co-elutants. The column combination BGB-176SE x Supelcowax-10 allowed the determination of all congeners that this enantioselective stationary phase was able to separate into enantiomers, i.e. PCBs 45, 91, 95, 136, 149 and 176. These column combinations have also been evaluated for the simultaneous determination of the 12 congeners with a toxic equivalency factor assigned by the WHO (PCBs 77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169, 189) and the seven indicator congeners (PCBs 28, 52, 101, 118, 138, 153 and 180), and evaluated for the analysis of food samples.     

The routine analysis of some specific isomers of polychlorinated biphenyl congeners in human milk

A mixture of 14 polychlorinated biphenyl (PCB) isomers of various congeners, representing approximately 70% of all human milk PCBs reported in the literature, was made up to identify and approximate their residues in human milk. Individual isomer levels varied from 5 to 103 nanograms per gram of milkfat with the 2,2',4,4',5,5'-hexachlorobiphenyl isomer as the major PCB contaminant of human milk. PCB isomer numbers 74, 118, 153, 138 and 180 made up approximately 75% of all PCBs as measured by this mixture. There was close agreement of total PCB isomer content in breast milk between electron capture gas chromatography and gas chromatographic mass spectrometry determinations. A major interference was encountered however for PCB isomer no. 52, whose residue level in the breast milk was approximately 3 X higher by gas liquid chromatography than by mass spectrometry.     

Optimized method for the determination of 25 polychlorinated biphenyls in water samples using stir bar sorptive extraction followed by thermodesorption-gas chromatography/mass spectrometry

An optimized method using stir bar sorptive extraction (SBSE) for the determination of 25 polychlorinated biphenyls (PCBs) from water samples among them three of the most toxic coplanar PCBs (PCB 77, PCB 126 and PCB 169) was developed. Since the investigated PCBs comprise all steps of chlorination (from PCB 1 as monochlorobiphenyl to PCB 209 as decachlorobiphenyl) the results should be representative for the total class of the 209 PCB congeners. For 8 ml spiked water samples with 2 ml methanol addition and 2 h exposure time of stir bars recoveries between 28% (PCB 209) and 93% (PCB 1, PCB 52, PCB 77) were found. Detection limits between 0.05 ng/l and 0.15 ng/l were calculated for the combination of SBSE and thermodesorption-GC/MS. The procedure was applied to the investigation of groundwater and river water samples from the industrial region of Bitterfeld northern Leipzig, Germany.