便携式气相色谱-质谱仪在应急监测中的应用

通过一次有机污染物应急监测实例,结合HAPSITE便携式GC-MS的使用情况,介绍了该仪器在应急监测与处置工作中的特点,并根据使用结果,总结了便携式GC-MS能够迅速确定污染范围,有效确定污染物种类以及快速确定污染状况和污染程度等性能特点,为相关单位对便携式GC-MS的实际应用提供了指导。     

气相色谱法测定苯酚生产废水中芳香族化合物

建立了用气相色谱法同时测定苯酚生产废水中异丙苯、α-甲基苯乙烯、α-甲基苯甲醇、2-苯基-2-丙醇、苯酚、苯乙酮、2-苯基丙醛等7种芳香族有毒有机污染物的定量分析方法。采用二氯甲烷对水样进行萃取后进行分析测定,气相色谱条件:DB-WAX型色谱柱,FID检测器,程序升温,进样量1μL。方法的检出限、精密度、回收率实验表明,该方法对苯酚生产废水中各污染物组分具有较好的分离效果,对7种物质的检测限均低于0.05 mg/L,5次测定的相对标准偏差小于5%,实际水样的加标回收率大于97%。     

便携式气相色谱质谱测定水中挥发性有机物再现性和准确度研究

建立了便携式顶空-气相色谱-质谱（HS-GC-MS）测定水中挥发性有机物的方法。以水中苯系物、卤代烃和氯代苯等VOCs为研究对象，在同一实验室内，使用3台便携式HS-GC-MS模拟现场应急监测环境开展检测活动，研究测定结果的再现性和准确度。实验结果表明，检测结果的相对标准偏差为0.7%~13%；绝大多数目标化合物测定结果的回收率为80%~120%。综合来看，方法的精密度和准确度基本满意，能够满足应急监测工作的需要。     

Determination of o-phthalic acid in snow and its photochemical degradation by capillary gas chromatography coupled with flame ionization and mass spectrometric detection

Phthalic acid and its photochemical degradation has been determined in snow and rainwater samples collected during winters (2003-2010) in the Southeast of Massachusetts using capillary gas chromatography (GC) with flame ionization and mass spectrometric detection. Water samples were dried using a rotary evaporator and derivatized with a 14% BF₃/methanol reagent before GC analysis. The developed method proved simple and accurate. Phthalic acid was found in snow samples collected in a concentration range of 7.22-76.5 nM. The photodegradation of phthalate was carried out under 300 nm UV light. The direct photodecomposition of the acid is slow (5% h⁻¹). However, the addition of dissolved Fe(III) species at 2.0 μM accelerated the light-induced degradation of phthalic acid by 3.5 times in the atmospheric water samples. Photodegradation rates of phthalic acid increases with decreasing pH value of water samples in the range of pH 2.8-4.5.     

水中丙烯酰胺气相色谱测定方法研究

研究建立了大口径毛细管柱气相色谱法测定水中丙烯酰胺的方法。优化了水中丙烯酰胺的衍生化条件,用乙酸乙酯和正己烷混合溶剂萃取衍生产物,萃取后直接进行色谱分离分析,水中丙烯酰胺的最低检测浓度为0.05μg/L,回收率在94.5%～113%之间;进行6次平行精密度试验,相对标准偏差低于11.5%。研究建立的气相色谱法简便、快速、准确、重现性好,定量、定性准确可靠,适合水中丙烯酰胺的分析测定。     

固相微萃取-气相色谱法测定水源地水中SVOC

采用固相微萃取-毛细管柱电子捕获气相色谱法测定水源地水中18种半挥发性有机物,优化了萃取纤维、时间、温度、pH值、转子转速、离子强度等萃取条件。方法线性良好,18种化合物的检出限为0.000 2μg/L~0.1μg/L,实际水样加标回收率为84.3%~109%。     

Gas/particle partitioning of atmospheric PCDD/Fs in a satellite town in Eastern China

Gas/particle partitioning of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in ambient air was investigated in a satellite town in Eastern China from April 2007 to January 2008 comprehending large temperature variations (from 3 to 34 °C, daily average). Molecular weight, molecular structure and ambient temperatures are the three major factors that govern the gas/particle partitioning of atmospheric PCDD/Fs throughout the year. Generally, good agreements were obtained (except for winter) between measured particulate fractions and theoretical estimates of both the Junge–Pankow adsorption model and Harner Bidleman absorption model using different sets of subcooled liquid vapor pressure and octanol–air partition coefficient (K_oa), respectively. Models utilizing estimates, derived from gas chromatographic retention indices (GC-RIs), are more accurate than that of entropy-based. Moreover, during winter, the K_oa-based model using the GC-RIs approach performs better on lower chlorinated PCDD/Fs than that of -based. Furthermore, possible sources of mismatch between measured and predicted values in winter (3–7 °C) were discussed. Gas adsorption artifact was demonstrated to be of minor importance for the phenomena observed. On the other hand, large deviations of slopes (m_r) and intercepts (b_r) in logK_p vs. plots from theoretical values are observed in the literature data and these are found to be linearly correlated with ambient temperatures (P<0.001) in this study. This indicates that the non-equilibrium partitioning of PCDD/Fs in winter may be significantly influenced by the colder temperatures that may have slowed down the exchange between gaseous and particulate fractions.     

广东省火电厂烟气脱硫装置的经济技术分析

简要介绍了广东省7个火电厂现有的5种烟气脱硫技术装置：海水脱硫、荷电干式烟气脱硫、湿式石灰石／石膏法烟气脱硫、DCL燃煤固硫剂脱硫及烟气循环流化床脱硫技术，对它们的经济、技术性进行了分析比较。     

简易石灰石/石膏湿法烟气脱硫技术在连州电厂的应用

在介绍了连州电厂的广东省第一套简易石灰石／石膏湿法烟气脱硫（FGD）系统主要设计参数和工艺流程的基础上，重点对FGD系统在近2年的运动过程中出现的主要问题进行了分析，包括系统与锅炉的相互影响，烟道腐蚀问题，脱硫石膏与灰渣水的混排及吸收塔内搅拌器叶片的损坏等，同时从技术，经济两方面对该套FGD系统进行了总体的评价。     

Natural gas engine driven heat pump system – a case study of an office building

ABSTRACT

An eQUEST model was developed to conduct a simulation study of a natural gas engine-driven heat pump (GEHP) for an office building in Woodstock, Ontario, Canada. Prior to the installation of the GEHP, the heating and cooling demands of the office building were provided by rooftop units (RTUs), comprising of natural gas heater and electric air conditioner. Energy consumption for both GEHP and RTUs were monitored for operation in alternating months. These recorded energy consumptions along with weather data were used in the regression analysis. The developed eQUEST models were validated and calibrated with the regression analysis results with respect to the ASHRAE Guideline 14–2014. The eventual models were then applied to investigate the potential annual energy consumption, greenhouse gas (GHG) emission and energy cost savings achieved by using the GEHP in Woodstock, and other cities in Canada, particularly in Ontario.