TOF–SIMS surface analysis of chemical components of size–fractioned urban aerosols in a typical heavy air pollution event in Beijing

Size–fractioned atmospheric aerosol particles were collected during a typical heavy air pollution event in Beijing. The organic and inorganic components on the surfaces of the samples were analyzed using time–of–flight secondary ion mass spectrometry(TOF–SIMS).The variation characteristics of the surface chemical composition and influencing factors were studied, and the possible sources of these chemical compositions were identified through principal component analysis. The results showed that inorganic components such as crustal elements and sulfate, and organic components such as aliphatic hydrocarbons and oxygen–containing organic groups were present. Some surface components, such as polycyclic aromatic hydrocarbons, heavy metals and fluorides may exert adverse effects on human health. The species and relative percentages of the chemical components varied with particle size, diurnal and pollution progress. During a heavy pollution event, the species and relative percentages of secondary components such as oxygen–containing organic groups and sulfurous compounds increased, indicating that particles aged during this event. The surface chemical composition of the aerosol particles was affected mainly by emissions from coal combustion and motor vehicles. In addition, air pollution, meteorological factors, and air mass transport also exerted a significant effect on the surface chemical composition of aerosol particles.     

A conductive polypyrrole based ammonium ion selective electrode

In view of the development of miniaturized sensor arrays, a solid-contact ammonium ion selective electrode has been investigated. A conductive polypyrrole film was electrochemicallydeposited on a glassy carbon surface and used as an internal solid contact layer between the sensing membrane and solid electrode surface. A systematic evaluation of the importantparameters affecting the electromotive force (emf) response ispresented. The performances of this solid-contact sensor were verified using a batch-mode measurement setup and a wall-jet flow cell system. The designed sensor exhibited excellent selectivity for the primary ion and a linear response over the pNH₄ ⁺ range 1–5 with a slope of 56.3 mV decade^-1. The sensor has a fast response and is relativelyrobustness, and was also used to determine ammonium concentrations in natural waters, with promising results.     

室内甲醛污染及对人体健康的影响

通过对三种不同类型居室内甲醛监测表明,甲醛浓度与室内装饰、吸烟和燃料的不完全燃烧有关.兰州地区夏季室内甲醛超标率高,为41.0％～51.3％.室内主要污染物除TSP以外,甲醛居第2位,且一天中浓度最高值在中午.新建居室比普通居室甲醛浓度高,在所有情况下,室内浓度高于室外.     

Rapid infiltration wastewater treatment for small communities in Beijing

This rapid infiltration (RI) system is proposed as the first one in China. The RI system treated 500 m3/d of municipal and industrial wastewater. About 0.36 ha of field was used. It has been evaluated that the RI system has an excellent ability to treat the wastewater. The infiltration rate was 50.3 m/a.     

人工湿地控制滇池面源水污染适用性研究

由于滇池面源污染主要发生在农村地区 ,而这些地区在水污染控制方面的资金投入和管理水平有限 ,所以应用于面源污染的水污染控制技术要求是低投入、易管理的工艺方法。而人工湿地是一种基建费用低 ,运行成本低 ,维护技术低的“三低”技术 ,氮磷去除效果显著 ,是一种适合应用于发生在农村地区的面源污染控制的工艺方法     

莲花电站库区水污染防治对策研究

莲花电站位于牡丹江干流下游,是一座以发电为主,兼顾防洪、养鱼等综合利用的大型水利枢纽工程.近年来,随着地区经济的快速发展,莲花电站下游用水量逐年增加,需要莲花电站补充一定的水量,并对水库水质提出了更高的要求.同时,上游牡丹江市经济的快速发展和人民生活水平的不断提高,导致进入莲花电站库区的污染物量增加,加剧了库区水体的污染程度.通过对水质现状分析,找出污染来源,提出莲花电站库区水污染防治对策.     

双极性脉冲高压介质阻挡放电降解氯苯和甲苯

将双极性脉冲高压引入介质阻挡反应器(螺旋棒式不锈钢电极、石英玻璃介质),分别对氯苯和甲苯的分解特性进行了实验研究.结果发现,这种放电形式可以高效注入能量,兼有脉冲电晕放电和介质阻挡放电的特点.脉冲高压使电场强度急剧增强,瞬间产生大功率放电和高能粒子,可以实现对VOCs化学键的高效裂解.与工频交流高压、单极性脉冲高压的试验结果比较表明,双极性脉冲高压取得了最高的降解效果;氯苯比甲苯难以分解.     

四原子氮有机胺三乙烯四胺吸收CO2的研究

在常压下,采用搅拌式反应器对三乙烯四胺(简写为TETA)吸收CO2进行了研究.测定了不同温度下,不同浓度的TETA对CO2的吸收情况,并与常用的醇胺吸收剂一乙醇胺(简写为MEA)、二乙醇胺(简写为DEA)、三乙醇胺(简写为TEA)的吸收效果作了比较;同时研究了TETA-有机胺-水三元混合体系对CO2 的吸收情况,结果表明:TEA-TEA-H2O对CO2 的吸收效果最好,且TETA/TEA=1/1时,吸收量最大,吸收速率最快.     

Renovated water reuse for rapid infiltration system

The renovated water in the rapid infiltration system (RI) as area for fish and duck farming is feasible. The flesh of fish and duck is edible. The farming of fish for 5 months and duck for 120 - 130 days can be accepted. It is beneficial to environment and economy, especially in developing countries. The production of fish and duck can make up for the cost of wastewater treatment.     

Changes of surface water pollution of Suzhou region:a case study in Taicang County, China

Environmental pollution is a by-product of industrialization when economy of a region is developing. China also suffers from such a problem, especially in the southern part like Suzhou region in Jiangsu Province. In this paper, data covering situations of surface water pollution and social and economic development showed that the surface water pollution in Taicang County, a typical economic zone of Suzhou region, is significantly correlated to the economic growth of this region.