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81.
Construction and demolition (C&D) waste dumped alongside roads and in open areas is a major source of soil and underground water pollution. Since 2006, Israeli ministry for environmental protection enacted a policy of vehicle impoundment (VI) according to which track drivers caught while dumping C&D waste illegally have their vehicles impounded. The present study attempted to determine whether the VI policy was effective in increasing the waste hauling to authorized landfill sites, thus limiting the number of illegal unloads of C&D waste at unauthorized landfill sites and in open areas. During the study, changes in the ratio between the monthly amount of C&D waste brought to authorized landfills sites and the estimated total amount of C&D waste generated in different administrative districts of Israel were examined, before and after the enactment of the 2006 VI policy. Short questionnaires were also distributed among local track drivers in order to determine the degree of awareness about the policy in question and estimate its deterrence effects. According to the study’s results, in the district of Haifa, in which the VI policy was stringently enacted, the ratio between C&D waste, dumped in authorized landfill sites, and the total amount of generated C&D waste, increased, on the average, from 20% in January 2004 to 35% in October 2009, with the effect attributed to the number of vehicle impoundments being highly statistically significant (t = 2.324; p < 0.05). By contrast, in the Jerusalem and Southern districts, in which the VI policy was less stringently enforced, the effect of VI on the above ratio was found to be insignificant (p > 0.1). The analysis of the questionnaires, distributed among the local truck drivers further indicated that the changes observed in the district of Haifa are not coincident and appeared to be linked to the VI policy’s enactment. In particular, 62% of the truck drivers, participated in the survey, were aware of the policy and 47% of them personally knew a driver whose vehicle was impounded. Furthermore, the drivers estimated the relative risk of being caught for unloading C&D waste in unauthorized sites, on the average, as high as 67%, which is likely to become a deterrent on its own. Our conclusion is that the VI policy appears to have a deterring effect on truck drivers, by encouraging them to haul C&D waste to authorized landfill sites. As we suggest, the research methodology implemented in the study and its results may help policy makers in other regions and countries, which experience similar environment enforcement problem, to analyze policy responses.  相似文献   
82.
Collection costs associated with servicing a major UK charity’s donation banks and collecting unsold goods from their retail shops can account for up to 20% of the overall income gained. Bank and shop collections are commingled and are typically made on fixed days of the week irrespective of the amounts of materials waiting to be collected. Using collection records from a major UK charity, this paper considers what vehicle routing and scheduling benefits could accrue if bank and shop servicing requirements were monitored, the former using remote sensing technology to allow more proactive collection scheduling. A vehicle routing and scheduling algorithm employing tabu search methods was developed, and suggested time and distance savings of up to 30% over the current fixed schedules when a minimum bank and shop fill level of between 50% and 60% was used as a collection trigger. For the case study investigated, this led to a potential revenue gain of 5% for the charity and estimated CO2 savings of around 0.5 tonnes per week across the fleet of six heterogeneous vehicles.  相似文献   
83.
汽车尾气对空气的污染越来越严重,影响人们的健康生活,破坏生态环境。机动车尾气中的氮氧化物是大气污染的主要污染物之一,采取有效措施减少机动车氮氧化物排放对于空气质量的改善具有重要意义。  相似文献   
84.
This study identified the levels and sources of heavy metal contamination in road dust from busy traffic areas in a typical industrial city in Korea. This study compared the total concentrations, as determined by aqua regia digestions and atomic absorption spectroscopy, of cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn) and nickel (Ni) in the road dust from areas with different characteristics such as traffic rotaries, downtown areas, circulation roads, and asphalt and concrete highways. The contamination levels of the heavy metals in the road dust were evaluated using the contamination factor and the degree of contamination. The contamination levels of the heavy metals in the road dust were highly dependent on traffic volume and atmospheric dispersion from traffic rotaries. Industrial emissions and the frequency of brake use and vehicles coming to a complete stop were additional factors that affected the contamination levels in downtown areas. The concrete highway had higher contamination levels of the heavy metals than the asphalt highway. Vehicle speed was also a strong contributing factor to the degree of contamination of heavy metals in the road dust from the circulation roads and highways.  相似文献   
85.
To devise and implement strategies to manage the quality of urban air, a metropolis needs air pollution data on which an air quality management plan can be formulated. Although air pollutants can come from several sources, many reports suggest that nitrogen dioxide from motor vehicle emissions is the major contributor to air pollution in cities. Since vehicles stop or move slowly through traffic intersections, concentrations of nitrogen dioxide (NO(2)) are expected to be relatively high at these sites. Inexpensive Ogawa passive samplers were placed at selected traffic intersections in the Durban Metropolis to trap the NO(2) which was then analysed by a sensitive laboratory-based method. The data obtained by this method was compared with data from sophisticated system comprising an active sampler cum on-line chemiluminescence detector. The sampling was done over a twelve month period to cover all seasons. Statistical analysis of the data showed that there was no significant difference between the means for the two methods. This study has established that an Ogawa passive sampler may be used as an economical and reliable collector for NO(2) in ambient air under varying climatic conditions. Further, the analysis method using a UV-Visible spectrophotometer was sensitive enough to detect NO(2) at the 10-20 ppb level. The cost of the method should be well within the budgets of most municipalities and it would motivate them to develop policies to alleviate traffic congestion.  相似文献   
86.
To investigate the impact of emission controls on ammonia (NH3) pollution in urban atmosphere, observation on NH3 (1 hr interval) was performed in Shanghai before, during and after the 2019 China International Import Expo (CIIE) event, along with measurements on inorganic ions, organic tracers and stable nitrogen isotope compositions of ammonium in PM2.5. NH3 during the CIIE period was 6.5±1.0 µg/m3, which is 41% and 32% lower than that before and after the event, respectively. Such a decrease was largely ascribed to the emission controls in nonagricultural sources, of which contribution for measured NH3 in control phase abated by ∼20% compared to that during uncontrol period. Molecular compositions of PAHs and hopanes further suggested a dominant role of the reduced vehicle emissions in the urban NH3 abatement during the CIIE period. Our results revealed that vehicle exhaust emission control is an effective way to mitigate NH3 pollution and improve air quality in Chinese urban areas.  相似文献   
87.
从雾和霾形成的原因以及与机动车尾气的关系等方面的论述,阐述了机动车尾气对人体健康的危害,提出了对机动车尾气的预防、治理办法。  相似文献   
88.
Atmospheric mixing ratios of carbonyl sulfide (COS) in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations (R2 > 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes (ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios.  相似文献   
89.
Atmospheric mixing ratios of carbonyl sulfide(COS) in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations(R2 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes(ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios.  相似文献   
90.
The imperatives for reducing the world's dependence on fossil and nuclear fuels have multiplied manifold in recent years with the advent of worldwide terrorism. These new dangers come in addition to the imperatives of addressing the dire consequences of global warming and devastating pollution that accompany the use of these fossil fuels. Reducing dependence on these unsafe and unreliable energy resources should be a top global priority. Implementation of proven energy efficiency technologies offers the world the fastest, safest, most economic and most environmentally benign way to alleviate these threats. This article outlines available efficiency measures, their economic advantages and means by which they may be and have been implemented. While examples of efficiency applications from both developed and developing countries are given, the article relies heavily on experience with energy efficiency in the United States, where data on efficiency is particularly abundant.  相似文献   
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