二恶英类物质检测分析技术进展

介绍了同位素稀释气相色谱质谱联用和生物快速检测法测定二恶英类化合物的技术进展,概述了国际通用的二恶英类标准分析方法体系,提出了各方法的适用范围,综述了我国二恶英类化合物分析研究现状并对我国二恶英分析检测提出了建议。     

毒性废水稀释中强度改变与浓度改变的跟随性研究

适用于已知毒物和毒性应用剂量测定的经典技术方法,以样品稀释过程中毒性强度改变与浓度改变的等比率跟随性为基础。废水中的毒性物质常以未知和混合为特征,高毒性的样品现状浓度距离方法预试验中最小全致死浓度较远,以已知毒物重铬酸钾毒性为对照,形成5种毒物高层级等强度毒性,通过这些高毒性废水同步等比率稀释后毒性改变的同步性测定试验,证明毒性废水稀释中强度改变与浓度改变的跟随状态具有不确定性。     

Effects of initial temperature and pressure on explosion characteristics of propane–diluent–air mixtures

The explosion characteristics of propane–diluent–air mixtures under various temperatures and pressures were investigated using a 20-L apparatus. The explosion limits of propane diluted with nitrogen or carbon dioxide were measured at high temperatures from 25 to 120 °C. The results showed that the upper explosion limit (UEL) increased, and the lower explosion limit (LEL) decreased with the rising temperature. The explosion limits of propane diluted with nitrogen or carbon dioxide were also measured at high pressures from 0.10 to 0.16 MPa. The results showed that the UEL increased, and the LEL almost remainedunchanged along with increased pressure. Under the same initial operating conditions, the concentration of nitrogen required to reach the minimum inerting concentration (MIC) point was higher than the concentration of carbon dioxide. Finally, the study investigated the limiting oxygen concentration (LOC) of propane under various initial temperatures, initial pressures, and inert gases. The LOC of propane decreased approximately linearly with increased temperature or pressure, and the LOC of propane dilution with carbon dioxide was greater than dilution with nitrogen from 25 to 120 °C or from 0.10 to 0.16 MPa, which indicated that the dilution effect of carbon dioxide was better than that of nitrogen.     

生化需氧量测定的稀释倍数研究进展

概述了稀释法测定生化需氧量（ＢＯＤ５）的基本要求，综述了近年来国内生化需氧量测定中有关稀释倍数研究的主要成果，分析评价了稀释法测定生化需氧量的一些数理公式。     

河口潮流和水质数值模拟研究

河口与海岸环境中污染物质的稀释扩散，是环境流体力学研究的重要课题，同时也是城市污水排海工程建设的关键技术之一。该文采用沿水深积分的平面二维非定常流动数学模型，来计算污染物质降解影响的溶解物质输运扩散过程，并以长江口水域为例，对潮汐水流中溶解物质的稀释扩散过程，进行了细致的数值模拟。结果表明，潮型，排放量，污染物质的降解等，对污水排放口的远场水质有明显的影响。     

欧盟工业废水污染物排放限值的制定

目前欧盟废水污染物排放限值的制定,主要依据欧盟委员会公布的污染综合防治指令和水政策行动框架指令的原则来进行。限值的制定方法主要有两种：一是以技术先进、经济合理为基础的最佳可行技术法;二是通过水环境质量标准、水体稀释能力以及污水处理系统削减能力来计算的反演法。中国可借鉴欧盟的先进方法进行环境标准体系的建设和完善。     

固定污染源排放可凝结颗粒物采样方法综述

综述了国内外固定污染源可凝结颗粒物(CPM)冲击冷凝法和稀释冷凝法2种采样方法,指出CPM是固定污染源排放颗粒物的重要组成部分,国内对于固定污染源CPM排放的监测和研究尚处于起步阶段,缺乏必要的CPM采样标准方法。通过分析2种采样方法的优缺点,提出冲击冷凝采样法需进一步降低SO_2等水溶性气体的影响,提高气相CPM冷凝效果及超细颗粒态CPM的捕集效率;稀释冷凝法需提高采样装置的便携性实现可过滤颗粒物(FPM)和CPM的分离采样,提高采样管路壁面颗粒物回收率。同时,针对我国固定污染源如燃煤电厂大量使用湿法脱硫设备的情况,CPM采样方法需提高对低温高湿且夹带液滴烟气采样的适用性。     

Evaluation of methods for the physical characterization of the fine particle emissions from two residential wood combustion appliances

The fine particle emissions from a U. S. certified non-catalytic wood stove and a zero-clearance fireplace burning Quercus rubra L. (northern red oak) and Pseudotsuga menziesii (Douglas fir) cordwood each at two different moisture levels were determined. Emission testing was performed using both time-integrated and continuous instrumentation for total particle mass, particle number, particle size distribution, and fixed combustion gases using an atmospheric wind tunnel, full-flow laboratory dilution tunnel, and dilution stack sampler with a comparison made between the three dilution systems and two sampling filter types. The total mass emission factors (EFs) for all dilution systems and filter media are extremely variable ranging from <1 to 55 g kg⁻¹ of dry wood depending on the combination of appliance type, wood species and moisture content, filter medium, and dilution system. For Teflon filter sampling of stove emissions in the wind tunnel, the total mass EFs varied from 2 to 8 g kg⁻¹ of dry fuel depending on wood type whereas the equivalent fireplace emissions burning wet oak averaged 11 g kg⁻¹. A substantial number of ultrafine particles in the accumulation size range were also observed during all tests as determined by an Electrical Low Pressure Impactor (ELPI) and Scanning Mobility Particle Sizer. The PM-2.5 (particles ≤2.5 μm in aerodynamic diameter) fractions determined from the ELPI electrometer data ranged from 93 to 98% (mass) depending on appliance type as reported previously by Hays et al. (Aerosol Science, 34, 1061, 2003).     

消除水中硫酸盐测定干扰的方法

铬酸钡间接原子吸收法测定水中硫酸盐时,样品的稀释倍数、盐度、酸度对测定结果影响较大.通过试验得出消除干扰的方法,使得测定结果准确、可信.     

超高效液相色谱-串联质谱法同时检测溴代阻燃剂

采用Acquity BEH C18色谱柱,以甲醇-乙腈混合液和水为流动相,辅以电喷雾正离子模式多反应监测(MRM)进行定性定量分析,建立了一种同位素稀释超高效液相色谱-串联质谱(UPLC-MS/MS)同时检测四溴双酚A(TBBPA)、三-(2,3-二溴丙基)异氰脲酸酯(TBC)和3种六溴环十二烷(HBCD)异构体的方法。水样通过固相萃取进行净化,回收率达到85.3%~96.1%。土壤和底泥样品经加速溶剂萃取后,采用酸性硅胶和中性硅胶柱进行净化,回收率达到81.5%~102.7%。该方法对TBBPA、TBC、α-HBCD、β-HBCD、γ-HBCD在水和土壤中的检测限分别为1.0、1.2、2.0、0.8、1.2 ng/L和0.10、0.12、0.20、0.08、0.12 ng/g。