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101.
Abstract

This study is a part of an ongoing investigation of the types and locations of emission sources that contribute fine particulate air contaminants to Underhill, VT. The air quality monitoring data used for this study are from the Interagency Monitoring of Protected Visual Environments network for the period of 2001–2003 for the Underhill site. The main source-receptor modeling techniques used are the positive matrix factorization (PMF) and potential source contribution function (PSCF). This new study is intended as a comparison to a previous study of the 1988–1995 Underhill data that successfully revealed a total of 11 types of emission sources with significant contributions to this rural site. This new study has identified a total of nine sources: nitrate-rich secondary aerosol, wood smoke, East Coast oil combustion, automobile emission, metal working, soil/dust, sulfur-rich aerosol type I, sulfur-rich aerosol type II, and sea salt/road salt. Furthermore, the mass contributions from the PMF identified sources that correspond with sampling days with either good or poor visibility were analyzed to seek possible correlations. It has been shown that sulfur-rich aerosol type I, nitrate aerosol, and automobile emission are the most important contributors to visibility degradation. Soil/dust and sea salt/road salt also have an added effect.  相似文献   
102.
Subway systems are considered as main public transportation facility in developed countries. Time spent by people in indoors, such as underground spaces, subway stations, and indoor buildings, has gradually increased in the recent past. Especially, operators or old persons who stay in indoor environments more than 15 hr per day usually influenced a greater extent by indoor air pollutants. Hence, regulations on indoor air pollutants are needed to ensure good health of people. Therefore, in this study, a new cumulative calculation method for the estimation of total amounts of indoor air pollutants emitted inside the subway station is proposed by taking cumulative amounts of indoor air pollutants based on integration concept. Minimum concentration of individual air pollutants which naturally exist in indoor space is referred as base concentration of air pollutants and can be found from the data collected. After subtracting the value of base concentration from data point of each data set of indoor air pollutant, the primary quantity of emitted air pollutant is calculated. After integration is carried out with these values, adding the base concentration to the integration quantity gives the total amount of indoor air pollutant emitted. Moreover, the values of new index for cumulative indoor air quality obtained for 1 day are calculated using the values of cumulative air quality index (CAI). Cumulative comprehensive indoor air quality index (CCIAI) is also proposed to compare the values of cumulative concentrations of indoor air pollutants. From the results, it is clear that the cumulative assessment approach of indoor air quality (IAQ) is useful for monitoring the values of total amounts of indoor air pollutants emitted, in case of exposure to indoor air pollutants for a long time. Also, the values of CCIAI are influenced more by the values of concentration of NO2, which is released due to the use of air conditioners and combustion of the fuel. The results obtained in this study confirm that the proposed method can be applied to monitor total amounts of indoor air pollutants emitted, inside apartments and hospitals as well.

Implications: Nowadays, subway systems are considered as main public transportation facility in developed countries. Time spent by people in indoors, such as underground spaces, subway stations, and indoor buildings, has gradually increased in the recent past. Especially, operators or old persons who stay in the indoor environments more than 15 hr per day usually influenced a greater extent by indoor air pollutants. Hence, regulations on indoor air pollutants are needed to ensure good health of people. Therefore, this paper presents a new methodology for monitoring and assessing total amounts of indoor air pollutants emitted inside underground spaces and subway stations. A new methodology for the calculation of cumulative amounts of indoor air pollutants based on integration concept is proposed. The results suggest that the cumulative assessment approach of IAQ is useful for monitoring the values of total amounts of indoor air pollutants, if indoor air pollutants accumulated for a long time, especially NO2 pollutants. The results obtained here confirm that the proposed method can be applied to monitor total amounts of indoor air pollutants emitted, inside apartments and hospitals as well.  相似文献   
103.
Recent catastrophic floods in Viet Nam have been increasingly linked to land use and forest cover change in the uplands. Despite the doubts that many scientists have expressed on such nexus, this common view prompted both positive forest protection/reforestation programs and often-unwarranted blame on upland communities for their forest management practices. This study discusses the disparity between public perceptions and scientific evidences relating the causes of catastrophic floods. The former was drawn on the results of a questionnaire and focus groups discussions with key informants of different mountainous communities, whereas the latter was based on GIS and remote sensing analysis of land cover change, including a statistical analysis of hydro-meteorological data of the Huong river basin in Viet Nam. Results indicate that there is a gap between the common beliefs and the actual relationship between the forest cover change and catastrophic floods. Undeniably, the studied areas showed significant changes in land cover over the period 1989–2008, yet, 71% of the variance of catastrophic flood level in the downstream areas appeared related to variance in rainfall. Evidences from this study showed that the overall increasing trends of catastrophic flooding in the Huong river basin was mainly due to climate variability and to the development of main roads and dyke infrastructures in the lowlands. Forest management policies and programs, shaped on the common assumption that forest degradation in the upland is the main cause of catastrophic flood in the downstream areas, should be reassessed to avoid unnecessary strain on upland people.  相似文献   
104.
创刊于1972年12月的《文教资料简报》是由南京师范学院(1984年易名为南京师范大学)内部编印的资料性月刊,主要目的是为文科教研服务。本文回顾该刊从创办至拥有"统一刊号"、从非正式出版物至成为正式出版物的历史沿革,具体观照该刊的编辑理念,总结该刊的内容特色、文献价值及经验启示。  相似文献   
105.
Japan's Eco-Town Program spearheaded in Japan the integration of Industrial Symbiosis and Urban Symbiosis, seeking to maximise the economic and environmental benefit from close geographic proximity of industrial and urban areas, through the use of previously discarded commercial, municipal and industrial waste materials in industrial applications. The program established 26 Eco-Towns around Japan. Approximately 1.65 billion USD was invested in 61 innovative recycling projects, with an average government subsidy of 36%. In addition at least 107 other recycling facilities have been constructed without government subsidy. 14 Eco-Towns primarily contributed to improving industry's productivity, whilst 10 Eco-Towns primarily contributed to improving environmental amenity. In 16 Eco-Towns the private sector was the most important actor supporting local government in the realisation of the Eco-Town, whilst in 9 Eco-Towns this was civil society. The availability of investment subsidies, the coming into force of ambitious recycling legislation with quantified, product-specific targets, access to the significant technological resources of the private sector, and widespread recognition of the urgency to act on environmental issues, all contributed to the success of the Eco-Town Program.  相似文献   
106.
107.
108.
Since 1994 UNIDO and UNEP cooperate in a Programme to establish National Cleaner Production Centres (NCPCs) as a mechanism for delivery of Cleaner Production (CP) services to businesses, governments and other organisations. In 2007, 38 NCPCs were operational in 37 developing and transition countries. While initially set up in near-identical ways in each country, over time NCPCs evolved in response to both programme-internal and country-level factors. The resulting diversity among NCPCs is described and analysed here. Differentiation and specialisation had occurred in service areas or topics both within and between NCPCs, however without a clear strategy for integration and synergy. NCPCs were becoming part of expanding networks of business services providers nationally forcing some to focus on audit and training services (tier 1), and others on specialist services in CP technology and/or policy (tier 2) and/or networking services (tier 3). All NCPCs were on a trajectory from a project management organisation to a nationally-owned entity. The different management requirements were not proactively managed and technical aspects of CP service delivery overshadowed institutional and governance aspects of establishing and operating the NCPC institution. Differences in service delivery methods between NCPCs are most evident in three service areas: CP assessments; policy advice; and transfer of Environmentally Sound Technologies. It is argued here that understanding root causes and benefits of this presently-observed differentiation, could lay the foundation for capturing and advancing best practice CP concepts, methods and policies. This in turn would enable strategic planning for customised interventions and support at the national level.  相似文献   
109.
To better understand arsenic (As) bioaccumulation, a soil invertebrate species was exposed to 17 field soils contaminated with arsenic due to mining activity. Earthworms (Eisenia fetida) were kept in the soils for 70 days under laboratory conditions, as body burden increased and failed to reach equilibrium in all soils. After 70 days of exposure, XANES spectra determined that As was biotransformed to a highly reduced form. Uptake kinetics for As was calculated using one compartment model. Stepwise multiple regression suggested that sorbed As in soils are bioaccessible, and uptake is governed by soil properties (iron oxide, sulfate, and dissolved organic carbon) that control As mobility in soils. As in soil solution are highly related to uptake rate except four soils which had relatively high chloride or phosphate. The results imply that uptake of As is through As interaction with soil characteristics as well as direct from the soil solution. Internal validation showed that empirically derived regression equations can be used for predicting As uptake as a function of soil properties within the range of soil properties in the data set.  相似文献   
110.
The concentrations of ammonium NH4+, nitrate NO3-, and nitrite NO2- ions were recorded along with ammonia (NH(3)) emission from a fertilized rice field located in the Kwangju province in South Korea over a period of 4 months (June to October 2006). The highest magnitude of NH(3) flux was 20,754 microg m(-2) h(-1), while the average flux value over the entire sampling period was 2,395 microg m(-2) h(-1). The highest ionic concentrations were 1.67, 0.44, and 0.71 ppm for NH4+, NO3-, and NO2- ions, respectively. Possible effects of soil pH on NH(3) fluxes were detected, as they concurrently exhibited a gradual and periodic change during the sampling period. Positive correlations existed between concentrations of NH4+ and NO2- ions and the soil pH. Positive correlations also existed between NH(3) emission flux and ambient (and water) temperatures. Results indicated that fertilizer application to rice can lead to significant emission of NH(3) along with NH4+ and NO3- ions.  相似文献   
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