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951.
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953.
The Gothenburg Protocol set national emission ceilings for transboundary air pollutants in 2010. These ceilings were formulated in 1999 using the Regional Air Pollution Information and Simulation (RAINS) model and national forecast data. The 2010 ceiling deadline is approaching as is a revision process which may lead to the setting of emission ceilings for 2020. This paper considers the original 1999 projections of six countries that were used within the RAINS model to inform the setting of their respective Gothenburg Protocol 2010 emission ceilings. These data are then contrast against recent inventory data and contemporary short-term forecasts out to 2010. These recent forecasts indicate that major downward shifts in the trends of pollutant emissions have been achieved, and whilst compliance challenges remain, there is a clear indication of the potential of such international agreements and their associated legislative and policy driven mechanisms. However, in a process governed by a maxim of achieving international environmental objectives at ‘least-cost’, the recent experience offers some valuable lessons. Specifically, in relation to the accuracy of energy projections and assumptions of other relevant variables in the modelling process. This paper considers these lessons and opens a discussion on the role of more adaptable mechanisms for the ongoing management of international agreements with long-term compliance horizons.  相似文献   
954.
以咸宁市消费者人群为研究对象,通过问卷调查统计并分析了消费者对政策(塑料购物袋收费)的行为响应。与此同时根据咸宁市统计年鉴和环境公报.统计估算了城市生活垃圾及白色污染的产生量及其变化趋势,研究结果表明:政府强制措施的出台限制了白色垃圾的产生量,但公众配合意愿尚不高。在此基础上,基于系统化原理,本研究提出了城市生活垃圾及白色污染治理的对策措施。  相似文献   
955.
The presence of human adenoviruses (HAdV) in recreational water might cause disease in the population upon exposure. HAdV detected by PCR could also serve as indicators of the virological water quality. In order to assess the applicability of HAdV to the evaluation of the faecal contamination in European bathing waters, a real-time quantitative PCR assay was used for the quantification of HAdV in 132 samples collected from 24 different recreational marine and freshwater sites in nine European countries. Selected samples presenting positive nested PCR results for HAdV were analyzed using quantitative PCR and 80 samples from a total of 132 produced quantitative results with mean values of 3.2 × 102 per 100 ml of water, being human adenovirus 41 the most prevalent serotype between the samples where adenovirus was typified. HAdV were quantified in samples from all 15 surveillance laboratories. Statistical analysis showed no homogeneous linear relation between HAdV and E. coli, intestinal enterococci or somatic coliphages concentrations in the tested samples when considering all the data together. Significant correlations between HAdV and at least one of the other indicators were observed only when data from individual laboratories were considered. The quantification of HAdV may provide complementary information in relation to the use of bacterial standards in the control of water quality in bathing water.  相似文献   
956.
Microbial melanin production by autochthonous bacteria was explored in this study as a means to increase U immobilization in U contaminated soil. This article demonstrates the application of bacterial physiology and soil ecology for enhanced U immobilization in order to develop an in situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE), Savannah River Site (SRS), South Carolina, as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >10(6) cells per g wet soil. Pyomelanin demonstrated U complexing and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in a field test demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments.  相似文献   
957.
PM(10) concentration and chemical composition (ions and carbon compounds) at three sampling stations in Rome and in its surroundings was determined daily during a one-month field study, carried out during December 2003. PM concentration at the traffic station was considerably higher than at the urban background and semi-rural stations; elemental carbon was detected as one of the chemical components responsible for this increase. The difference in the concentration of sulphate and ammonium was negligible, as it was expected for secondary pollutants. A negative artefact in the determination of ammonium nitrate by means of heated automatic monitors was highlighted. The dilution properties of the lower atmosphere were traced by means of a natural radioactivity monitor. This parameter has been found to play an essential role in pollution buildup. A considerable increase in PM concentration was observed to coincide with periods of atmospheric stability. The main difference in PM composition between periods of high concentration and periods of "clean" air was found to be in the increase of ammonium nitrate concentration.  相似文献   
958.
Human serum and plasma from Sweden (n=17), the United Kingdom (the UK) (n=13) and Australia (n=40) were analyzed by high performance liquid chromatography coupled to mass spectrometry. The objective was to identify different perfluorooctane sulfonate (PFOS) isomers. Similar isomer patterns typical for the electrochemical fluorination (ECF) process were found for all samples. The linear PFOS (L-PFOS) was the major isomer found (58-70%) followed by the monosubstituted PFOS isomers 1/6-CF(3)-PFOS (18-22%) and 3/4/5-CF(3)-PFOS (13-18%). Disubstituted isomers were also detected. The percentage of L-PFOS found in the serum and plasma samples was lower compared to a standard PFOS product (76-79%). The pattern of PFOS isomers in human serum and plasma may be suggestive concerning potential isomeric discrimination since PFOS is only produced by ECF. Possibilities for such isomer discrimination are discussed. Significant higher content of L-PFOS (68%) in Swedish samples compared to Australia and the UK (59%) was also found, which may suggest differences in exposure sources for humans.  相似文献   
959.
This paper presents an environmental system study of the production of propionic acid in a biorefinery system based on agricultural by-products. Here, propionic acid is produced by fermentation of glycerol, a by-product from biodiesel production, as carbon source and potato juice, a by-product from starch production, as nitrogen source. Biomass-based propionic acid leads to a greenhouse gas reduction of 60% compared to propionic acid from fossil sources. However, the primary energy input is about twice as high for the biomass-based propionic acid. The choice of input energy and the efficiency of the process, as well as the technology applied, have high impacts on the environmental performance of the biorefinery concept. There is a potential for increased integration both on the input of substrates and the output of end products of the biorefinery system, which will further improve its environmental performance.  相似文献   
960.
Exposure to bioaerosols associated with wastewater treatment processes may represent an occupational health risk for workers at wastewater treatment plants (WWTPs). A high frequency of acute symptoms in the gastrointestinal tract among the wastewater workers at a Danish WWTP has been reported. The objective of the study was therefore to examine the exposure of the workers to aerosolised microorganisms. Sampling of inhalable endotoxin, bacteria, moulds and viruses was performed on one occasion using personal samplers. Noroviruses (NoVs) and endotoxin were detected at concentrations that could pose an occupational health risk and possibly contribute to the increased frequency of gastrointestinal illness among the workers and should therefore be investigated further. In addition, positive correlations between exposure to endotoxin, bacteria, moulds and NoVs were found and indicate that the exposure to bioaerosols may be related to work tasks. This is the first study directly showing an occupational exposure to airborne NoVs by its detection in airborne dust.  相似文献   
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