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41.
气相色谱法测定苯酚生产废水中芳香族化合物 总被引:1,自引:1,他引:0
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%。 相似文献
42.
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. 相似文献
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44.
固相微萃取-气相色谱法测定水源地水中SVOC 总被引:1,自引:0,他引:1
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%。 相似文献
45.
Gas/particle partitioning of atmospheric PCDD/Fs in a satellite town in Eastern China 总被引:3,自引:0,他引:3
Meng-xia Xu Jian-hua Yan Sheng-yong Lu Xiao-dong Li Tong Chen Ming-jiang Ni Hui-fen Dai Fei Wang Ke-fa Cen 《Chemosphere》2009,76(11):1540-1549
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 (Koa), respectively. Models utilizing estimates, derived from gas chromatographic retention indices (GC-RIs), are more accurate than that of entropy-based. Moreover, during winter, the Koa-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 (mr) and intercepts (br) in logKp 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. 相似文献
46.
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。 相似文献
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48.
Altamash Ahmad Baig Farshad Kimiaghalam Rakesh Kumar JuanLi Ma Alan S. Fung 《International Journal of Green Energy》2020,17(8):476-487
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. 相似文献
49.
锚索拉断火花引爆瓦斯的实验研究 总被引:3,自引:0,他引:3
设计了锚索拉断火花引爆瓦斯实验装置 ,在瓦斯浓度为爆炸范围的环境中 ,对锚索拉断时产生火花规律及引起瓦斯爆炸的可能性进行了一系列实验研究。结果表明 :锚索拉断产生火花的概率为 5 0 % ,锚索钢绞线破断产生的火花不能引起瓦斯爆炸。采用红外热成象仪对锚索拉断火花温度的测试表明 ,锚索拉断产生的火花最高温度远小于瓦斯爆炸所需的最低点燃温度 6 5 0℃。 相似文献
50.
J. Karnesky P. Chatterjee F. Tamanini S. Dorofeev 《Journal of Loss Prevention in the Process Industries》2007,20(4-6):447-454
A three-dimensional gasdynamic model with constant burning rate is applied for the prediction of the maximum pressure rise from gaseous combustion in vented enclosures. A series of calculations for an enclosure with aspect ratio close to unity are presented. Both cases with and without obstacles in the enclosure are considered. Results of calculations are compared with a simple 0D solution for spherical vessels. It is shown that, in cases without obstacles, the 0D solution for the maximum reduced overpressures is close to the predictions of the detailed modeling. In cases with obstacles, the detailed simulation gives significantly higher overpressures than those from the 0D model. However, in all the cases the reduced pressures are correlated well with the maximum flame surface area. 相似文献