顶空固相微萃取-气相色谱-质谱联用技术测定水中8种致臭物质方法优化

研究建立了顶空固相微萃取-气相色谱-质谱联用测定水中8种致臭物质的方法。通过试验研究确立了顶空固相微萃取的最优化条件:氯化钠加入量0.4g/mL,萃取时间40min,萃取温度70℃,搅拌速率500r/min,解析时间3 min,无需调节pH。在试验条件下,8种致臭物质在1~100ng/L内线性关系良好,R2为0.997~0.999 9,最低检出限为0.5~1ng/L,相对标准偏差为1.6%~3.8%,加标回收率为89.2%~105.4%。     

固相萃取-气相色谱质谱联用测定水中半挥发性有机物的研究

建立了固相萃取(SPE)与气相色谱-质谱(GC/MS)联用测定水样中半挥发性有机物(SVOC)的方法。结果表明,用这项技术可以得到可靠的校正曲线,各半挥发性有机物在0.5μg/L～10μg/L范围内有良好的线性关系,检出限分别在0.02μg/L～0.20μg/L之间,回收率在54%～124%之间,相对标准偏差在0.9%～10.0%之间。     

固相萃取气相色谱法测定水中痕量有机磷农药

分别采用C8,C18和HLB小柱萃取水样中的痕量有机磷农药（敌敌畏、内吸磷、乐果、甲基对硫磷、马拉硫磷、对硫磷）,以毛细柱气相色谱火焰光度检测器（FPD）进行测定,用甲醇-丙酮（70/30,V/V））洗脱3种不同的固相萃取小柱。C18小柱萃取回收率最好,平均回收率89.22%-101.93%。     

浅谈固相微萃取-气质联用在水体有机污染物检测中的应用条件

针对目前固相微萃取-气质联用在水体有机污染物检测中缺乏推荐条件,本文从固相微萃取条件、气质条件等5个方面综合介绍了亟待优化和规范的实验条件,为进一步研究和推广新的水体有机污染物检测标准提供参考。     

固相微萃取-气质联用法在水体嗅味物质测定中的应用

采用固相微萃取-气质联用法对水体中常见嗅味物质土臭素(GEO)和2-甲基异莰醇(2-MIB)进行分析测定。选取65μm PDMS/DVB纤维萃取头,经实验确定最佳萃取条件:Na Cl投加量为6 g;水浴温度为70℃;萃取时间为30 min。用内标法测定结果显示:GEO和2-MIB在5~900 ng/L范围内标准曲线线性良好,且该法检出限低,对GEO和2-MIB的检出限分别为0.5 ng/L和0.7 ng/L;精密度(RSD)分别为0.31%和0.94%;加标回收率分别为107%和103%,能够满足分析测试要求。     

固相萃取-高效液相色谱三重四级杆质谱联用法在北方河流水体氯霉素类抗生素测定中的应用

建立了固相萃取-高效液相色谱三重四级杆质谱联用法,同时测定水中的4种氯霉素类抗生素(氯霉素、甲砜霉素、氟苯尼考和氟苯尼考胺)残留,采用MRM扫描方式在正/负模式下,在10 min内完成对氯霉素类抗生素的分析,该方法线性范围为1~100μg/L,相关系数R20.99,实际水样加标回收率为92.8%~117.48%。利用该方法对北方河流水样进行采样调查,其中氟苯尼考检出率较高为26%,达526.36 ng/L。该方法操作简便,灵敏度高,重现性好,具有一定的推广价值。     

固相萃取-气相色谱法测定饮用水中的DDT和BHC

借鉴美国环境保护局规定中的有机氯农药分析方法,利用Agilent 6890N气相色谱仪/微电子捕获检测器(μ-ECD)以及固相萃取预处理技术,对饮用水中的DDT和BHC的成分进行分析测定.该测定方法快速、简洁、重复性好,线性相关系数＞99.9%,并且样品回收率不低于88%,用于测定实际样品结果满意.     

吹扫捕集-气相色谱质谱联用测定水中挥发性有机物的研究

建立了吹扫捕集(Purge-and-Trap)与气相色谱-质谱(GC/MS)联用测定水样中挥发性有机物(VOC)的方法,探讨了该方法可能出现的问题,提出了一些简单的解决方案,并对GC/MS条件进行了优化。结果表明,用这项技术可以得到可靠的校正曲线,各挥发性有机物在0.4μg/L～60μg/L范围内有良好的线性关系,检出限分别在0.0021μg/L～0.20μg/L之间,回收率在95.6%～106.4%之间,相对标准偏差在2.2%～4.4%之间。     

固相萃取-高效液相色谱法测定水中的酚类化合物

详细介绍了水中酚类化合物的测定方法。在固相萃取工作站上建立的酚类预处理方法稳定性好,筛选出的三种弱极性萃取小柱,回收率较高。采用流动相梯度淋洗,紫外检测器波长编程的方法测定富集后的酚类化合物,并测定了方法的精密度、准确度和检测限。     

固相萃取-高效液相色谱检测原水中微量内分泌干扰物

提出了检测饮用水中几种微量存在的内分泌干扰物的仪器分析方法.检测对象包括邻苯二甲酸二甲酯(DMP),邻苯二甲酸二丁酯(DBP),双酚A(BPA),壬基酚(NP),阿特拉津(Atrazine)等,采用固相萃取技术对水样进行预处理,利用高效液相色谱进行分析,DMP,DBP,BPA,NP和Atrazine的超纯水加标回收率、原水加标回收率均可达到70%以上;对上海市饮用水水源黄浦江进行了初步的水质调查,分别检测出较高含量的二丁酯、双酚A、壬基酚和阿特拉津.     

超声提取/气相色谱-质谱法测定涂料中的8种有机磷阻燃剂

建立了采用超声提取进行前处理,结合气相色谱-质谱法检测技术同时测定涂料中8种有机磷阻燃剂(OPFRs)的检测方法。经对比和优化超声提取过程中的提取溶剂、温度、时间和次数等试验条件,发现以丙酮为提取溶剂,设定提取温度30℃和提取时间15 min,重复提取2次时,回收率较好。配制标准曲线的线性范围为10~1 000 ng/mL,采用气相色谱-质谱法应用选择性离子扫描方式进行定量分析,结果表明,8种OPFRs的线性回归方程的相关系数均不低于0.990 4,方法的检出限为0.04~0.26 ng/mL,在阴性涂料基质中的加标回收率为79.3%~112.0%,平行样的相对标准偏差小于等于6.4%。应用该方法测定市售5家企业的涂料产品时,仅在一家企业的样品中检出TCEP,含量为15.22 ng/mL。     

地下水中21种半挥发性有机物测定方法的优化研究

为研究建立同时测定地下水中21种半挥发性有机物的固相萃取-气相色谱-串联质谱(SPE-GC/MS)法,采用C_(18)和HLB固相萃取柱对地下水样品进行富集萃取,DB-5MS毛细管柱(30 m×0.25 mm×0.25μm)进行气相分离,单离子监测(SIM)扫描模式进行分析,并对进样速率、洗脱剂和pH等样品前处理条件进行优化,建立了固相萃取-气相色谱-质谱测定地下水中21种半挥发性有机物的检测方法。研究结果显示:21种半挥发性有机物的标准曲线在0.1～1μg/mL范围内,线性关系良好。平均回收率基本在80%～120%之间,精密度在1.70%～8.79%之间,检出限在0.022～0.045μg/L之间,均低于《地下水质量标准》(GB/T 14848—2017)一类水限值。研究结果表明,本方法操作简便、有机试剂消耗量少、灵敏、准确,可用于地下水中多种半挥发性有机物的同时检测。     

Fates of Organic Compounds from Niagara Falls Dumpsites in Lake Ontario

Sediment samples from the western portion of Lake Ontario were analyzed for chlorinated organic compounds using gas chromatography and gas chromatographic mass spectrometry. Both electron impact and negative chemical ionization mass spectrometry were employed. Many of the chlorinated compounds previously found to be leaking into the Niagara River from waste disposal sites in the city of Niagara Falls were identified in the sediments of Lake Ontario. In particular, two unique chlorofluorinated compounds were found in the lake's sediment, showing that stable compounds introduced into the Niagara River accumulate to detectable levels 100 km away in Lake Ontario. Chlorinated styrenes as well as several highly chlorinated poly cyclic aromatic hydrocarbons were also found. Their exact origin is uncertain at this time.     

Identification and Determination of Trace Organic Substances in Sediment Cores from the Western Basin of Lake Ontario

A study was carried out to identify and to determine organic chemicals in sediment from the western basin of Lake Ontario, particularly in the fine-grained sediments near the mouth of the Niagara River. Sediment cores were obtained at five sampling stations, and samples were extracted by the base/neutral and acid method designed by US Environmental Protection Agency for extraction of water samples. The identification of organic compounds in the base/neutral sediment extract was carried out by GC/MS techniques. The major classes of investigated contaminants were aromatics, polynuclear aromatics, alkylated polynuclear aromatics, alkylated benzenes, phthalates, methyl esters of fatty acids, olefins, aldehydes, chlorobenzenes, and benzoates. In addition, all sediment samples were analysed for 2,3,7,8-tetrachloro dibenzo-p-dioxin. In the surface sediments, the abundance of contaminants decreased with the distance from the Niagara River mouth toward the north-west. However, high concentrations of most of the detected organics were present in sediment at the station located east of the River mouth.     

光声光谱技术应用于变压器油中溶解气体分析

变压器油中溶解气体在线监测装置中的色谱柱和气敏传感器存在消耗被测气体和长期稳定性差等不足。光声光谱气体分析技术灵敏度高,不消耗被测气体,克服了传统油中溶解气体在线监测技术的缺点。文中对其在变压器油中溶解气体在线监测中的应用进行了研究。构建了用于变压器油中溶解气体分析的光声光谱平台,给出具有红外特征吸收峰的CH4 ,C2 H6 ,C2 H4 ,C2 H2 ,CO和CO2 这6种主要故障特征气体的特征频谱,采用加权最小二乘法对2种混合气体中的CH4 ,C2 H6 ,C2 H4 ,C2 H2 ,CO和CO2 进行了定性和定量分析。分析结果与气体各组分体积分数真实值或气相色谱仪测量值的比较表明,光声光谱技术能有效地对变压器油中溶解气体进行分析。     

Tetrachloro-9H-Carbazole,a Previously Unrecognized Contaminant in Sediments of the Buffalo River

Three sediment samples taken from the Buffalo River, New York, have been analyzed for polychlorinated planar molecules similar in structure to the highly toxic 2,3,7,8-TCDD. Although no TCDD was found, residues of chlorinated dibenzofuran, fluorene, biphenylene, phenanthrene (anthracene), naphthalene, and 9H-carbazole were identified. l,3,6,8-tetrachloro-9H-carbazole was identified as the major chemical of this type in the sediments, and quantified at levels as high as 25 ng/g at one site.     

Environmental Impact of Two,Adjacent, Hazardous Waste Disposal Sites in the Niagara River Watershed

Sediment core samples were taken from the Niagara River at locations adjacent to the Love Canal and the 102nd Street dumps, two hazardous waste disposal sites in the City of Niagara Falls, New York. The samples were analyzed by capillary gas chromatographic mass spectrometry, and a variety of halogenated organic compounds (including chlorobenzene, -toluene, -naphthalene, -benzyl, and -norbornane derivatives) were identified and quantified. Based on the qualitative and quantitative data obtained, the sources of these pollutants were identified, and the relative migration of chemicals from the two dumps to the Niagara River was established. The impact on the river is localized to the immediate vicinity of the outfall of the sewer draining the Love Canal neighborhood. Remedial action could be as easy as removing 20 truckloads of contaminated sediment from the river.     

关于测定水中亚硝酸盐氮、硝酸盐氮、总氮的方法探讨

含氮化合物是水体污染监测中的重要指标,因此需要可靠精确的检测方法作为支撑。本文采用气相分子吸收光谱法对亚硝酸盐氮、硝酸盐氮、总氮进行检测分析,结果表明:标准曲线相关系数均大于0.999,检出限、精密度、准确度、加标回收率均满足方法要求。表明气相分子吸收光谱法具有较高的灵敏度和准确度,稳定性好,可实现样品在线自动稀释和在线消解,简化样品前处理过程,更适用于大批量含氮化合物水质检测工作。     

固定化光合细菌对含酚废水的生物降解试验

对实验室保存的光合细菌用不同浓度的模拟含酚废水进行驯化后,采用RCVBN液体培养基对光合细菌进行扩大培养,并用海藻酸钠-壳聚糖-活性炭微胶囊法对光合细菌进行固定。分别用固定化光合细菌和非固定化光合细菌在不同的温度和不同的接种量下对含酚废水进行降解。以苯酚含量为降解效果指标,结果表明:两种状态下的光合细菌均可以降解含酚废水,但是它们对苯酚的降解率各不相同,固定化光合细菌优于非固定化光合细菌。进一步的正交试验结果表明:影响固定化光合细菌处理含酚废水各因素的影响次序分别为:温度、接种量、pH值,其最佳降解条件是温度为30℃,接种量为20%,pH值为7.0,此时废水中苯酚降解率为85.3%。