Screening the emission sources of volatile organic compounds (VOCs) in China by multi-effects evaluation

We develop a multi-effect evaluation method to assess integrated impact of VOCs. Enable policy-makers to identify important emission sources, regions, and key species. Solvent usage and industrial process are the most important anthropogenic sources. Styrene, toluene, ethylene, benzene, and m/p-xylene are key species to be cut. Volatile organic compounds (VOCs) play important roles in the atmosphere via three main pathways: photochemical ozone formation, secondary organic aerosol production, and direct toxicity to humans. Few studies have integrated these effects to prioritize control measures for VOCs sources. In this study, we developed a multi-effects evaluation methodology based on updated emission inventories and source profiles, by combining the ozone formation potential (OFP), secondary organic aerosol potential (SOAP), and VOC toxicity data. We derived species-specific emission inventories for 152 sources. The OFPs, SOAPs, and toxicity of each source were estimated, the contribution and sharing of source to each of these adverse effects were calculated. Weightings were given to the three adverse effects by expert scoring, and then the integrated effect was determined. Taking 2012 as the base year, solvent use and industrial process were found to be the most important anthropogenic sources, accounting for 24.2% and 23.1% of the integrated effect, respectively, followed by biomass burning, transportation, and fossil fuel combustion, each had a similar contribution ranging from 16.7% to 18.6%. The top five industrial sources, including plastic products, rubber products, chemical fiber products, the chemical industry, and oil refining, accounted for nearly 70.0% of industrial emissions. Beijing, Chongqing, Shanghai, Jiangsu, and Guangdong were the five provinces contributing the largest integrated effects. For the VOC species from emissions showed the largest contributions were styrene, toluene, ethylene, benzene, and m/p-xylene.     

Air quality improvement in Los Angeles—perspectives for developing cities

Air quality improvement in Los Angeles can inform air quality policies in developing cities. Emission control efforts, their results, costs and health benefits are briefly summarized. Today's developing cities face new challenges including regional pollution. Air quality issues in Beijing are briefly compared and contrasted with Los Angeles. Opportunities for co-benefits for climate and air quality improvement are identified. Air quality improvement in Los Angeles, California is reviewed with an emphasis on aspects that may inform air quality policy formulation in developing cities. In the mid-twentieth century the air quality in Los Angeles was degraded to an extent comparable to the worst found in developing cities today; ozone exceeded 600 ppb and annual average particulate matter <10 mm reached ~150 mg·m⁻³. Today's air quality is much better due to very effective emission controls; e.g., modern automobiles emit about 1% of the hydrocarbons and carbon monoxide emitted by vehicles of 50 years ago. An overview is given of the emission control efforts in Los Angeles and their impact on ambient concentrations of primary and secondary pollutants; the costs and health benefits of these controls are briefly summarized. Today's developing cities have new challenges that are discussed: the effects of regional pollution transport are much greater in countries with very high population densities; often very large current populations must be supplied with goods and services even while economic development and air quality concerns are addressed; and many of currently developing cities are located in or close to the tropics where photochemical processing of pollution is expected to be more rapid than at higher latitudes. The air quality issues of Beijing are briefly compared and contrasted with those of Los Angeles, and the opportunities for co-benefits for climate and air quality improvement are pointed out.     

机场大气污染研究现状综述

经济的发展驱动着航空业的进步,同时带来了机场大气污染问题。概述了机场大气污染的危害、基本原理,认为飞机排放是大气温室效应的直接污染源。进而对国内外典型的机场大气排放评估模型进行对比分析,并分析研究了飞机尾气污染防治措施。     

新型饮用水除氟材料Bio-F除氟机制研究

采用了SEM、BET、FT-IR、XRD等现代分析测试方法,研究了Bio-F的表面微观结构及吸附氟离子机制.结果表明,Bio-F吸附氟离子后比表面积由12.411m2·g-1减少为10.692m2·g-1,平均孔容减少了0.004 cm3·g-1,最可几孔径分布在1.88nm左右.Bio-F吸附氟离子的过程包括离子交换和吸附作用,吸附方式包括物理吸附和化学吸附,离子交换时材料与氟离子结合可能形成Ca10(PO4)5CO3(OH)F.     

Odor compounds from different sources of landfill: characterization and source identification

This study investigated the odor compounds from different areas in a landfill site, which included the municipal solid waste (MSW)-related area, the leachate-related area and the sludge-related area. Nine sampling points were placed and 35 types of odorous substances were measured and quantified from these grabbed samples. The results showed that the main odorous substances emitted from landfill site were styrene, toluene, xylene, acetone, methanol, n-butanone, n-butylaldehyde, acetic acid, dimethyl sulfide, dimethyl disulfide and ammonia. In the MSW-related area, the highest concentrations of oxygenated compounds were observed at the gas extraction wells (GW), while sulfur compounds were rare. Ammonia in the sludge-related area was very abundant. Sludge discharge area (SD1) and sludge disposal work place (SD2) were representative points of pre- and post-drying, in which the characterizations of the emitted odorous gas were different. After chemical drying, the concentration of ammonia increased, whereas those of volatile fatty acids and sulfur compounds decreased. In the leachate-related area, relatively low concentrations of all those odorants were detected in leachate storage pool (LS), which may be due to the enclosure operation of the leachate storage pool. Using principal components analysis and cluster analysis, GW, SD1 and SD2 were distinguished from the other sampling points. The typical odorants in GW were acetaldehyde, ethyl benzene, xylene, methylamine and dimethyl formamide. The typical odorants in SD1 were methyl mercaptan, valeric acid and isovaleric acid, while those in SD2 were carbon disulfide, acetone, 3-pentanone, methanol and trimethylamine. The typical odorants in other sampling points were hydrogen sulfide, n-butylaldehyde and acetic acid.     

上盖一体化地铁车站结构非线性地震响应分析∗

基于 ABAQUS 软件建立了地下地铁车站?土?上盖建筑一体化结构大型三维有限元数值模型,计算分析了上盖一体化地铁车站结构的地震响应规律和破坏机理,探讨了上盖一体化地铁车站结构与单体车站结构地震响应的差异。结果表明：地铁上盖一体化结构体系各阶自振频率与自由场地较为接近,地铁上盖结构的存在对场地动力特性的影响较小;强震作用下,一体化地铁车站结构的损伤破坏区域主要是车站各层楼板和墙柱的交接位置,尤其是中柱和侧墙顶底部的损伤最为严重;单体车站与上盖一体化地铁车站结构地震响应规律存在一定差异,上盖一体化地铁车站结构的地震反应略小,其中,上盖地铁车站结构的地震响应同时受上盖结构和周围土体介质的影响, 上盖结构对上盖地铁一体化区域的影响显著,周围土体对上盖地铁非一体化区域的影响显著。     

Self‐protective reactions to peer abusive supervision: The moderating role of prevention focus and the mediating role of performance instrumentality

Across 3 studies, we apply a self‐protection perspective of observed mistreatment to examine a moderated mediation model on “when” and “why” third parties are motivated by peer abusive supervision. We hypothesize that prevention‐focused third parties will increase their performance effort as a response to peer abusive supervision, and this effect is mediated by performance instrumentality. In a field study of working adults (Study 1) and an experimental study that manipulated peer abusive supervision (Study 2), we found that peer abusive supervision interacted with third parties' prevention focus to predict their performance effort such that peer abuse was positively related to third parties' performance effort only for those high on prevention focus. Results were replicated in a second field study of working adults (Study 3). Further, we found support for the mediating effect of performance instrumentality. The theoretical and practical implications of our results are discussed.     

The health hazards of potentially toxic metals in the daily diets of adults and children from a mining and smelting region (Hezhang County) in southwestern China

Toxic metals accumulated in the human body are predominantly absorbed by the digestive tract in non-occupationally exposed populations. In the current study, we collected plowed soil samples, and investigated the varied food compositions in a mining and smelting area in southwestern China, to measure the concentrations of ten potentially toxic metals—As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sr, and Zn. We collected information on the daily intakes of these metals to assess the health risks associated with their exposure among children and adults. The urine concentrations of the metals were also measured to obtain data on the amounts present in the body. The results showed that the hazard indexes (HIs) of As, Ba, Cd, Cr, Ni, Pb, and Sr were all larger than 1, for both adults and children; the Zn and Cu values were comparatively higher in children. The intake of staple foods of the region posed the greatest health risk, while drinking water only posed risks clearly associated with As exposure. The urine samples of local residents contained larger amounts of As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn, confirming the hazards in the health risk assessment. Obvious differences in the urine metal concentrations between men and women were confirmed. In conclusion, higher concentrations of metals in the surface soil and rain water were the predominant cause of elevated exposure through home-grown crops and produce to accumulate in local residents’ bodies.     

新时期生态环境监测数据产品内涵和发展建议

简述了新时期环境监测数据产品内涵,分析了当前数据产品在信息化程度、深度开发、数据质量和信息公开等方面存在的问题;提出,要不断提高数据产品的信息化水平,推进其深度开发,要立足于服务社会和管控需求,加强数据产品可追溯能力建设,针对现各部门存在的"数据孤岛"问题,增强各部门间监测数据的可比性,推进区域污染物排放、空气环境质量、水环境质量等信息公开,为政府决策提供准确的技术支持,为公众、企业提供优质服务。     

Humic Acid Transport in Water-Saturated Porous Media

The presence of humic acid (HA) in water poses environmental problems because it enhances the transport of several contaminants. A series of column experiments was conducted toward studying HA transport in different porous media under various pH, ionic strength, and flow rate conditions. The results showed that decreasing pH and increasing ionic strength increased adsorption and therefore delayed the transport of HA in porous media. However, increasing flow rate accelerated the transport of HA in porous media. The effects of pH, ionic strength, and flow rate varied with the solid matrix and were more evident in sands of smaller average particle diameter than in those with larger ones. These factors must be considered when predicting the environmental fate of HA. The results also suggested that HA adsorption was an important process controlling HA transport and should be considered in studies of HA behavior in porous media.