固上顶空气相色谱法测定樟脑和萘

本文对固上顶空气相色谱法的理论和测定条件进行了研究。用于樟脑和萘的测定，最小检出量达１０－９ｇ，回收率为９６．０～１０１．３％．本法基体干扰小，操作简便．     

顶空气相色谱法测定水中三氯甲烷四氯化碳的参数优化及测定影响因素探讨

本文探讨了如何提高顶空气相色谱法测定三氯甲烷及四氯化碳的灵敏度、精密度与准确度。重点讨论了平衡条件的优化以及带顶空自动进器的气相色谱仪的各个关键参数的优化。     

顶空固相微萃取-气相色谱-串联质谱法测定水中2,4,6-三氯酚

建立了顶空固相微萃取-气相色谱-串联质谱法(HS-SPME-GC-MS-MS)测定水中2,4,6-三氯酚的方法。优化条件下,在1. 00～50. 0μg/L质量浓度范围内线性响应良好(r~2=0. 999 1);检出限0. 224μg/L,测定下限0. 896μg/L;加标样相对标准偏差(RSD)为4. 15%～6. 24%;加标回收率为81. 0%～115%;单个样品检测总时间40 min。该方法萃取与气相色谱-串联质谱分析在线一步完成,操作简便、灵敏度高、抗干扰性强,适用于地表水、生活饮用水、工业废水等水体中2,4,6-三氯酚的检测。     

应急监测中便携式顶空/GC-MS法测定水中VOCs的初步研究

通过对实验室加标水样和实际水样的测定,研究了便携式顶空/气相色谱-质谱法(GC-MS)与吹扫捕集/GC-MS法测定水中VOCs的性能比较,探讨了利用Loop环测定水中高浓度VOCs的准确度. 结果表明:便携式顶空/GC-MS测定水中54种低浓度VOCs的检出限略高于吹扫捕集/GC-MS系统,准确度和精密度分别为67.4%～136%和9.08%～19.80%,均满足环境应急监测分析的要求;利用Loop环,便携式顶空/GC-MS可对水中高浓度级(mg/L)VOCs进行较为准确地测定,回收率为100%～149%;复杂的实际样品基本不干扰便携式顶空/GC-MS的测定,与吹扫捕集/GC-MS法相比,二者对实际水样的测定结果相对偏差小于20%;便携式顶空/GC-MS在水污染事故现场可得到基本准确的结果,可为事故后续处理提供有效的数据支持.      

顶空-气相色谱法测定地表水中松节油

采用顶空-气相色谱法测定地表水中松节油,并对顶空瓶的平衡温度、平衡时间,盐析效应和取样量等顶空条件进行优化,使方法在0.200 mg/L~4.00 mg/L范围内线性良好,方法检出限为0.037 mg/L。实际样品2个质量浓度水平的加标回收率为89.3%~108%,RSD分别为5.8%和4.8%。     

顶空气相色谱法测定饮水中氰化物

采用顶空气相色谱法，测定饮水中氰化物。对水样保存特殊性的影响，色谱柱的选择及实验条件进行研究。结果表明，CN^-浓度在1-18ug/l呈线性关系，最低检出限为0．35ug/l，高、中、低三浓度测定相对标准偏差分别为2．68％、6．69％、6．98％，回收率范围83．4-119．2％，满足卫生检验要求。是一种简便快速、实用性强的分析方法。     

顶空气相色谱法测定水中三氯乙醛的条件控制

探讨了顶空气相色谱法测定水中三氯乙醛的条件控制，阐述了加碱量对测定结果的影响，以及加热温度过高或加热时间过长导致三氯甲烷响应值变低的原因。结果表明，在5.0 mL水样中加入0.4 mL 5 mol/L NaOH水溶液，于45 ℃条件下加热30 min，可使目标产物三氯甲烷的响应值及稳定状态达到最佳。方法在2.00 μg/L～30.0 μg/L范围内线性良好，检出限为0.5 μg/L。对三氯甲烷背景浓度较高的自来水样品的加标回收率为88.3%～105%，RSD为6.3%。     

地表水样品中10种卤代烃测定方法的优化

对地表水样品中10种卤代烃测定方法进行优化,找出空白偏高的原因。方法优化后的加标回收率为90.1%~104%,相对标准偏差为1.1%~6.9%,检出限为0.000 3μg/L~2.0μg/L,可满足地表水环境质量分析要求。     

顶空-气相色谱法测定固定污染源废气中挥发性脂肪胺

采用顶空-气相色谱法测定固定污染源废气中甲胺、二甲胺、乙胺、二乙胺和三乙胺,通过优化相关测定条件,使5种挥发性脂肪胺在0.005 mg/L～25.0 mg/L范围内线性良好,方法检出限为0.004 mg/m3～0.4 mg/m3(以采集20 L空气样品计).5种挥发性脂肪胺的加标回收率为91.0％～113％,6次测定结...     

Monitoring and modelling of siloxanes in a sewage treatment plant in the UK

Monitoring of cyclic volatile methylsiloxanes (cVMS) carried out at Anglian Water’s Broadholme sewage treatment plant (STP) is described. The method deployed used headspace gas chromatography/mass spectrometry (HS-GC/MS) and the addition of isotopically labelled cVMS to correct for partitioning in samples containing high levels of particulate and dissolved organic carbon. The method was capable of measuring cVMS in raw sewage samples, with recoveries of 80%, 85% and 71% respectively, for D₄, D₅ and D₆. The limit of quantification was 0.2 μg L⁻¹ for all three substances. Recoveries close to 100% were observed for all cVMS spiked into treated effluent (LOQ = 0.01 μg L⁻¹). Despite the volatile nature of cVMS and its ubiquitous presence in the ambient atmosphere, the methods deployed showed excellent recoveries, reproducibility and quantification limits. A distinct diurnal variation in cVMS concentration, probably linked with the use of personal care products was observed for raw sewage but not in treated sewage effluent. The estimated per capita consumption of D₅ (∼2.7 mg cap⁻¹ d⁻¹) derived for the population served by this plant was significantly lower than that derived in the Environment Agency (UK) risk assessment (11.6 mg cap⁻¹ d⁻¹). The cVMS were highly removed during sewage treatment with efficiencies greater than 98%. The methods and findings of this pilot study can be used as the basis for future studies on the fate of cVMS substances in STPs.