对TH_PKU-300B挥发性有机物快速在线监测系统的改进

针对现有TH_PKU-300B挥发性有机机物快速在线监测系统在测定含氧挥发性有机化合物(OVOCs)、含氮挥发性有机物(NVOCs)和高沸点挥发性有机物时存在灵敏度低、精密度差、线性响应较差、记忆效应明显等不足,根据其原理,对其GC-MS通道的部分气路进行改进。通过实验对比分析,证明改进后的仪器系统响应更加灵敏、线性拟合度更高、精密度及解析效率均显著提高,同时检出限也由改进前的体积分数0.1×10~(-9)~1.0×10~(-9)降低至0.02×10~(-9)~0.08×10~(-9),并解决了记忆效应问题。改进后的系统在OVOCs、NVOCs和高沸点挥发性有机物测定方面要优于原系统。     

噪声自动监测系统的运行维护管理

对噪声自动监测系统在运行过程中遇到的各种情况进行分类和总结,详细介绍了南通市环境监测中心站的相关工作经验,提出从设备故障、突发事件、软件错误等方面出发,对噪声自动监测的运行维护进行综合管理。     

空气自动监测系统运行维护与管理方法初探

根据乐山市空气自动监测系统多年来的运行管理实践,通过对长光程环境空气质量自动监测系统的性能和特征的了解掌握,论述了进行预防性维护、定期巡检维护和现场故障排除的重要性,提出了系统运行维护和管理的方法以及常见故障分析处理技术。     

XH2000A型空气连续自动监测系统常见故障及其解决方法

我站XH2000A型空气连续自动监测系统在2年多的运行过程中，多次遇到仪器故障和技术问题，通过对总体站房系统的探索和实践，整理了一些常见故障，并着重于实际条件，总结出主要依靠自身来排除故障的方法，同时提出一些降低仪器故障发生率、延长配件使用寿命及解决系统技术问题的建议。     

气相色谱／傅立叶变换红外光谱（GC／FT—IR）系统分析有机污染物

1 概述气相色谱(GC)可卓有成效地分离测定环境样品中复杂、痕量、多组分的有机污染物,而傅立时变换红外光谱能提供完整的分子结构信息,因而GC/FTIR系统兼两者之长,适于分离、鉴定多组分的混合物,GC/FTIR系统具有如下几个特点:     

地表水水质自动监测系统常见故障及原因分析

笔者针对该市环境地表水水质自动监测系统自运行以来出现的故障,详细介绍了对其的诊断解决方法,并对引起故障的所有可能因素进行了总结,由此笔者还对地表水自动监测系统的日常维护提出了一些建议。     

DOAS环境空气质量自动化监测系统运行维护

介绍了DOAS环境空气质量自动化监测系统的性能和特征,指出该系统在日常运行时,需要进行预防性定期例行维护和现场故障排除,总结分析了该系统运行维护的方法,并对常见故障作了剖析.     

环境空气中痕量挥发性有机硫监测分析方法研究

采用预浓缩系统与GC MS联用,建立了环境空气中痕量挥发性有机硫的分析方法,该法用苏玛罐或Tedlar袋采集空气样品在预浓缩系统中经液氮于-160℃冷冻浓缩后,进入GC MS进行分析。甲硫醇、乙硫醇、甲硫醚、乙硫醚、二甲二硫的最低检出限分别为2 0、1 0、1 0、1 0、0 5μg m3。经6次的重复测定,其相对标准偏差小于9 0%。该方法已用于环境空气的测定,取得了令人满意的结果。     

我国污染源在线监控系统建设运行及对策措施研究

介绍了我国污染源在线监控系统建设运行现状,阐述污染源在线监控系统建设运行过程中存在的问题,对如何解决这些问题进行研究,提出相应对策措施.     

水体有机污染物分析的研究进展

评述了水体有机污染物分析中GC、GC-MS、LC、GC-FTIR等方法的特性和适用范围,介绍了应用各种分析方法分析水体有机污染物的研究现状,提出了水体有机污染物分析的发展方向。     

VOCs在线监测系统与SUMMA罐采样-气质联用法的比对分析

将挥发性有机污染物在线监测系统与实验室内SUMMA罐采样气质联用法(GC-MS)的挥发性有机物分析进行了标准气体和实际空气样品的分析比对,并对偏差原因作分析,提出在线监测系统的维护建议。结果表明,挥发性有机物在线监测系统的监测结果与实验室方法有一定的可比性,可用于大气中挥发性有机污染物的在线监测。     

食品企业周边空气中异味挥发性有机物测定方法比较

以1个典型食品生产企业(酱菜厂)周边的异味挥发性有机物监测为例,介绍了罐采样-GC/MS、便携式GC/MS、SPME-GC/MS以及SPME-异味分析系统等4种监测方法的实际应用,从定性、定量监测结果等方面,比较了4种监测方法的特点。罐采样-GC/MS、便携式GC-MS 2种方法适用于定性、定量检测,在有标准样品的前提下,定量结果总体可比;SPME-GC/MS以及SPME-异味分析系统2种方法更适用于定性检测。     

GC-MS测定土壤中酞酸酯类化合物

采用毛细管柱气相色谱-质谱联用选择离子检测(GC-MS-SIM)技术,结合快速萃取和佛罗里硅土柱净化方法分析土壤中的六种酞酸酯类(PAEs)化合物。结果表明,六种PAEs峰形好,平均加标回收率为76.7%~110%,相对标准偏差为2.5%~4.5%。方法具有操作简便、回收率高、纯化效果好和对环境友好的特点,且具有很强的实用性。     

GC和HPLC测定水中苦味酸的比较

建立了气相色谱法(GC)和高效液相色谱法(HPLC)测定水中苦味酸的分析方法,并对2种方法进行比较。GC法检出限为0.000 4 mg/L,线性范围为0.0~0.050 mg/L,加标回收率为92.3%~94.1%,相对标准偏差为4.6%~8.9%。HPLC法检出限为0.02 mg/L,线性范围为0.10~5.00 mg/L,加标回收率为93.7%~96.5%,相对标准偏差为1.3%~2.0%。2种方法相比,GC法灵敏度较高,可用于痕量分析,但操作烦琐,不能有效地将苦味酸与硝基酚类干扰物分离;而HPLC法虽然灵敏度较差些,但简单、快速、稳定性好、准确度高,可有效地将苦味酸与硝基酚类干扰物分离。     

Ambient level volatile organic compound (VOC) monitoring using solid adsorbents--recent US EPA studies

Ambient air spiked with 1-10 ppbv concentrations of 41 toxic volatile organic compounds (VOCs) listed in US Environmental Protection Agency (EPA) Compendium Method TO-14A was monitored using solid sorbents for sample collection and a Varian Saturn 2000 ion trap mass spectrometer for analysis. The adsorbent was a combination of graphitic carbon and a Carboxen-type carbon molecular sieve. The method detection limits (MDLs) for 11 samples were typically 0.5 parts per billion by volume (ppbv) and lower except for bromomethane and chloromethane, both of which exhibited breakthrough. Thirty-day sample storage on the sorbents resulted in less than a 20% change for most compounds, and water management was required for humid samples to avoid major anomalous decreases in response during analyses. The adsorbent-based system, a system using canister-based monitoring, and a semi-continuous automated GC/MS (autoGC) monitoring system with a Tenax GR/Carbotrap B/Carbosieve S-III adsorbent preconcentrator were compared using spiked ozone concentrations as a variable. In this comparison, the target compounds included a number of n-aldehydes as well as those listed in TO-14A. The effects of ozone on the TO-14A compounds were relatively minor with the exception of negative artifacts noted for styrene and 1,1,2,2-tetrachloroethane. However, a small, systematic decrease in response was evident for a number of aromatic VOCs and 1,1,2,2-tetrachloroethane when ozone was increased from 50 to 300 ppbv. Method averages for multiple runs under the same conditions were typically within +0.25 ppbv of their mean for most compounds. For n-aldehydes, strong positive artifacts using the autoGC preconcentrator and strong negative artifacts for the canister-based and carbon sorbent approaches caused major disagreement among methods. These artifacts were mostly eliminated by using MnO2 ozone scrubbers, although loss of the n-aldehydes for all methods occurred after a single sample collection of 1 h duration, apparently due to the interaction of the n-aldehydes and products of the O3, MnO2 reaction on the scrubber.     

加速溶剂萃取-固相萃取小柱净化-气相色谱法测定土壤中有机磷农药

建立了加速溶剂萃取-固相萃取小柱净化-气相色谱法测定土壤中12种有机磷农药的方法。推荐了12种有机磷农药快速分离的色谱条件。采用加速溶剂萃取技术实现了对土壤中有机磷农药残留的提取,选取最佳条件参数,减少了组分的损失,提取回收率达88%～108%。选择不同填料的SPE小柱和洗脱溶剂形成3种方案法进行净化实验,结果表明,方案2采用混合溶剂(正己烷、丙酮、二氯甲烷体积比为1∶1∶1)洗脱上样后的硅胶SPE小柱的净化效果好,回收率为91%～121%。方法检出限为0.000 1～0.000 2 mg/kg,石英砂基体和实际污染土壤样品加标回收率为62%～112%,相对标准偏差为0.7%～8.6%。该方法操作简便,快捷,灵敏度高,检出限低,试剂用量少,准确度和精密度符合质量控制要求。     

GC/MS内标法测定土壤中多环芳烃的质量控制

阐述了GC/MS内标法测定土壤中多环芳烃时质量控制的基本内容、基本方法和基本操作。测定结果为：空白分析结果均小于检出限;空白加标精密度和准确度分别在7.80%~25.2%和49.2%~96.6%之间;样品加标精密度和准确度分别在7.77%~19.8%和67.2%~122%之间;检出限在0.05~0.08 mg/kg之间...     

Simplified determination of lipophilic metabolites of nonylphenol ethoxylates: method development and application in aqueous samples from Buenos Aires, Argentina

In the present work we have developed an analytical methodology for the determination of nonylphenol (NP) and nonylphenol mono- and di-ethoxylates (NP1EO and NP2EO) in water samples. The applicability of this methodology was proved by means of the analysis of environmentally relevant aqueous samples from Buenos Aires. This constitutes a starting point for a rigorous assessment of the incidence of NPnEO surfactants in Argentina, as only very few, qualitative or semi-quantitative data on the occurrence of these compounds in local systems were available up to this time. Enrichment of the analytes was carried out by solid-phase extraction on a C-18 sorbent, followed by elution with ethyl acetate. Normal-phase high performance liquid chromatography on an amino-silica column and fluorescence detection at excitation-emission wavelengths of 230-300 nm were employed for separation and quantification of the analytes. Confirmation of peak assignment in selected real samples was performed by off-line coupling HPLC with GC-MS analysis. A non-polar GC capillary column was used, and a characteristic peak pattern was obtained for the alkyl chain isomers of each ethoxylated homologue and NP. GC-MS analyses yielded in all cases purity levels higher than 80% for the HPLC collected fractions. The elevated concentrations found for the estrogenic metabolites of NPnEO are in accordance with an unrestricted use of this class of non-ionic surfactants in the country.     

全二维气相色谱-飞行时间质谱法分离复杂体系中7种指示剂 多氯联苯

采用全二维气相色谱-飞行时间质谱法(GC×GC TOF-MS)分析了混标样品Aroclor 1260、Aroclor 1254、Aroclor 1242中的多氯联苯(PCBs)单体,考察了在复杂体系下对7种PCBs指示剂的分离能力。结果表明,与优化柱系统的分离效果相比,136种单体的混标样品中共分离出121种单体,7种指示剂经一维和二维的保留时间及质谱定性,在121种单体的2D斑点图中清晰可辨。全二维对于复杂体系的PCBs和指示剂的分离表明其强大的分离能力和对于检测复杂体系中指示剂的分辨能力,对该类物质的定性和定量检测具有重要意义。