以下是网学网为您推荐的应用化学-气相色谱，希望本篇文章对您学习有所帮助。
论文编号:HG208 论文字数:10726,页数:31
摘要：本文研究了食品中毒性较大的PCBs77、81、105、114、118、123、126、156、157、167、169、189测定方法，采用高速冷冻离心法、固相萃取小柱法对测试的式样提纯、净化，采用高效分离的气相色谱-电子捕获检测法(GC-ECD)，和高灵敏度、良好定性定量特点的质谱法(MS)，对食品中的多氯联苯进行了检测研究。
通过对气相色谱法中恒压程序、恒流程序以及程序升温法所得结果的比较，得出了气质联用分析多氯联苯的最佳实验操作条件。并且发现在气相色谱法中采用载气的恒线速度控制方式可以提高分离度，缩短分析时间。
利用所建立的方法测定了食品中毒性较大的样品，12种多氯联苯的线性范围0.001-2µg/L；相关系数r在0.99左右，回收率范围在96.25%-117.5%之间，RSD%<21%，方法检测限在0.4ppb-0.5ppb范围内。
随着公众对多氯联苯（PCBs）认知度的提高，PCBs和PCBs污染废物必须引起高度重视、合理收集和安全处置，以防止PCBs扩大环境污染。目前我国PCBs的研究工作主要集中在清单调查、环境污染水平监测和分析方法上，对PCBs的检测技术尚缺乏研究，特别是食品中的PCBs残留检测亟待加强。随着我国履行斯德哥尔摩公约的国家行动方案的制定和开展，PCBs的检测技术将成为持久性有机污染物控制领域的研究热点之一。
关键词：多氯联苯；电子捕获检测器；气相色谱-质谱；冷冻离心；固相萃取；
Abstract: This paper studies determination of larger toxicity the PCBs77, 81,105,114, 118,123,126,156,157,167,169,189 in food, high-speed freezing centrifuge, solid phase extraction column test method style purification, purification, separation with high efficiency gas chromatography - electron capture detection (GC-ECD), and high sensitivity, good qualitative and quantitative characteristics of mass spectrometry (MS). Through the constant pressure on the gas chromatography process, constant process and the programmed temperature method comparison of results obtained with GC-MS operating conditions for optimum PCBs. And found that the use of gas chromatography carrier gas of constant linear speed control method can improve the separation, shortening analysis time. With the established method of determination of toxicity of food in larger samples, 12 kinds of PCBs in the linear range of 0.001-2μg / L; correlation coefficient r is about 0.99, recoveries of 96.25% -117.5%, and RSD% <21%, detection limit in 0.4ppb-0.5ppb range.
With the public polychlorinated biphenyls (PCBs) increase awareness, PCBs and PCBs contaminated waste must be identified as soon as possible, reasonable collection and safe disposal, to prevent PCBs continue to pollute the environment. PCBs present our research work mainly in the list of investigations, the level of environmental pollution monitoring and analysis methods for detection of PCBs is still a lack of technology. Along with the Stockholm Convention implementation of national action programs to develop and carry out, PCBs in the detection technology will be a persistent organic pollutant control one of the hot area of research.
Keyword: PCBs; electron capture detector; gas chromatography - mass spectrometry; freeze centrifuged; solid phase extraction;
目录
中文摘要 I
英文摘要 II
目录 III
1 绪论 1
1.1实验研究的目的、意义 2
1.2实验的提取检测方法 3
2 实验部分 6
2.1 PCBs的物理和环境化学性质、固相萃取(SPE)技术简介 6
2.1.1 PCBs的物理和环境化学性质 6
2.1.2 固相萃取(SPE) 7
2.2 实验方案 7
2.3仪器和试剂 7
2.3.1仪器 7
2.3.2试剂及样品 8
2.4操作方法 9
2.5测定 11
2.5.1气相色谱分析条件 11
2.5.2质谱分析条件 11
2.5.3空白实验 11
2.5.4方法限量 11
2.5.5回收率 11
2.5.6计算 12
3.结果与讨论 13
结论 25
致谢 26
参考文献 28
