Evolutionary processes and sources of high-nitrate haze episodes over Beijing, Spring

Rare and consecutive high-nitrate haze pollution episodes were observed in Beijing in spring2012. We present detailed characterization of the sources and evolutionary mechanisms of this haze pollution, and focus on an episode that occurred between 15 and 26 April. Submicron aerosol species were found to be substantially elevated during haze episodes, and nitrates showed the largest increase and occupation(average: 32.2%) in non-refractory submicron particles(NR-PM_1), which did not occur in other seasons as previously reported. The haze episode(HE) was divided into three sub-episodes, HEa, HEb, and HEc. During HEa and HEc, a shallow boundary layer, stagnant meteorological conditions, and high humidity favored the formation of high-nitrate concentrations, which were mainly produced by three different processes —daytime photochemical production, gas-particle partitioning, and nighttime heterogeneous reactions — and the decline in visibility was mainly induced by NR-PM_1.However, unlike HEa and HEc, during HEb, the contribution of high nitrates was partly from the transport of haze from the southeast of Beijing — the transport pathway was observed at ~800–1000 m by aerosol Lidar —and the decline in visibility during HEb was primarily caused by PM_(2.5). Our results provide useful information for air quality improvement strategies in Beijing during Spring.     

饮用水水源有机污染研究综述

由于工业的发展,特别是近年来化学工业的迅速发展,使原本就十分短缺的饮用水资源受到了严重的污染。本文综述了国内外饮用水水源有机污染的现状,分析了有机污染物的种类、特点及对人体健康的危害,同时也介绍了目前几种国内外水质检测中的常用分析方法。     

Toxicity-oriented water quality engineering

• Toxicity-oriented water quality monitoring was proposed. • Toxicity-oriented water quality engineering control was proposed. • Future issues to the proposition were discussed. The fundamental goal of water quality engineering is to ensure water safety to humans and the environment. Traditional water quality engineering consists of monitoring, evaluation, and control of key water quality parameters. This approach provides some vital insights into water quality, however, most of these parameters do not account for pollutant mixtures – a reality that terminal water users face, nor do most of these parameters have a direct connection with the human health safety of waters. This puts the real health-specific effects of targeted water pollutant monitoring and engineering control in question. To focus our attention to one of the original goals of water quality engineering – human health and environmental protection, we advocate here the toxicity-oriented water quality monitoring and control. This article presents some of our efforts toward such goal. Specifically, complementary to traditional water quality parameters, we evaluated the water toxicity using high sensitivity toxicological endpoints, and subsequently investigated the performance of some of the water treatment strategies in modulating the water toxicity. Moreover, we implemented the toxicity concept into existing water treatment design theory to facilitate toxicity-oriented water quality control designs. Suggestions for the next steps are also discussed. We hope our work will intrigue water quality scientists and engineers to improve and embrace the mixture water pollutant and toxicological evaluation and engineering control.     

Verification results of jet resonance-enhanced multiphoton ionization as a real-time PCDD/F emission monitor

A jet resonance-enhanced multiphoton ionization (REMPI) monitor was tested on a hazardous-waste-fired boiler for its ability to determine concentrations of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs). Jet REMPI is a real-time instrument capable of highly selective and sensitive (from parts per billion to parts per trillion) detection of a broad range of aromatic compounds, including a number of air toxic compounds. The PCDD/F toxic equivalency (TEQ) value was derived from a predetermined correlation (R ² = 0.74) with monochlorobenzene (MClBz). This relationship was applied to nine subsequent jet REMPI on-line measurements of MClBz and parallel, standard extractive sampling for PCDD/F TEQ. For high waste-firing rates, with a range of PCDD/F TEQ values between 3.9 and 6.0 ng TEQ/m³, the TEQ values predicted by jet REMPI had a relative difference of 26% with the standard EPA Method 23 results. At low waste-firing rates (0.9–1.6 ng TEQ/m³), the relative difference increased to 219%. This limited testing shows that jet REMPI has promise as an on-line diagnostic monitor, providing feedback on the effects on PCDD/F emissions of operating parameter changes such as fuel feed interruptions or air pollution control failures.     

一种监控煤矿轴流风机喘振的方法

分析了轴流风机喘振的产生、特性及其造成的危害;研究了轴流风机喘振监控的工作原理,即以压力传感器和控制电路为核心元件组成喘振监测装置,通过数字显示、声光报警及断电等形式监控轴流风机的运行状态;论述了喘振监测装置、喘振保护值的设置、安装及喘振监测装置的性能试验方法;介绍了轴流风机喘振时的现象及应急措施,为监控轴流风机的安全可靠的运行提供了可借鉴的经验。     

煤矿安全监控装备可靠性评价方法的研究

针对如何评价和选择矿井安全监控系统装备的问题。运用科学的方法，就几种不同型号装备，做了定量和定性的阐述，还就建立监测系统装备的可靠性评价结构模型和数学分析模型做了分析。也对其他几个人为影响因素的性能指标提出了定性分析方法。     

城市电磁波辐射污染监测及防护

电磁波辐射不仅对通信、无线电管理、电器设备的正常工作有许多干扰,而且对生物体也有严重的影响。为了更有效地避免因射频、微波等高频电磁场对城市居民身心健康的危害,进行城市电磁波辐射水平的监测与评价,并为此采取相应的防护措施是十分必要的。在1990年,用我国研制的电磁环境辐射监测仪对厦门、漳州两城市的电磁波辐射污染进行了测试和评价,为我国各大中城市进行电磁波辐射污染测试和评估提供了切实可行的方法。     

污染源监测中样品采集质量控制方法

现场监测及核查的重要环节包括采样点位、采样断面、现场工况等方面。针对这些环节,尤其是废气现场工况核查部分提出质量监控方法,并以现场推算复核的方式有效解决监测现场中经常出现的问题。     

中文智能pH在线监控仪及其算法开发

介绍了中文智能ｐＨ在线监控仪的性能、工作原理，功能及软件硬件设置，分析讨论了几咱不同的控制算法。     

利用GDY-101SA现场甲醛测定仪监测室内空气中的甲醛含量

本文对GDY-101SA现场甲醛测定仪监测室内空气甲醛含量的优势进行了分析,并对国标“GB／T18204．26-2000酚试剂比色法”和101SA仪进行样品的对比实验分析及显著性差异的检验,得出了GDY-101SA现场甲醛测定仪与酚试剂比色法所测结果无显著性差异的结论,且101SA测定仪省时省力,是开展室内甲醛监测的理想仪器之一。