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81.
机动车尾气净化控制的一个难点在于冷启动阶段,此时由于温度较低,催化剂尚未完全起作用,导致排出的污染物浓度较高。阐述了活性炭纤维的基本特性,特别是其低温吸附与催化性能对NO和CO的转化作用,讨论了活性炭纤维作为机动车尾气净化材料所需的改性及方法,并展望了其应用前景。  相似文献   
82.
To improve the estimation accuracy of battery’s inner state for battery management system, an online parameters identification algorithm for Thevenin battery model is researched. The Thevenin model and parameters identification algorithm based on recursive least square adaptive filter algorithm was built with the Simulink/xPC Target. The results of hardware-in-loop experiment, which uses Federal Urban Driving Schedule test to verify the parameters identification approach, show the proposed approach can accurately identify the model parameters within 1% maximum terminal voltage estimation error, and the State of Charge error which calculated by the open circuit voltage estimates can be efficiently reduced to 4%.  相似文献   
83.
This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.  相似文献   
84.
In this study, performances of Iranian thermal power plants have been assessed with respect to human factors such as job stress, satisfaction and security through data envelopment analysis (DEA). In the first step performance of power plants (DMUs) have been evaluated considering traditional production factors including installed capacity, internal consumption and fuel consumption as inputs and gross production as output (model 1). In the next step, model 1 is expanded to include three above mentioned human factors (model 2). Power plants have been ranked based on their relative efficiency scores in both models. Pearson and Spearman correlation coefficients between relative efficiency scores and rankings of power plants in two models have been calculated. The results show that efficiency scores and rankings of power plants in two models are quite different indicating that mentioned human factors have direct impact on overall performance of generation companies and that if we were to use just traditional factors it would not reflect the optimum efficiency of the DMUs. Finally, job security has been found as the most effective human factor in Iranian power plants. This is the first study that presents an integrated approach for assessment of electric power plants considering job stress, security and satisfaction. And it is shown that these human factors play important role in overall performance of generation companies.  相似文献   
85.
In this study, ammonia emissions characteristics of typical light-duty gasoline vehicles were obtained through laboratory vehicle bench test and combined with New European Driving Cycle (NEDC) condition and Worldwide Harmonized Light Vehicles Test Cycle (WLTC) condition. The influence of ambient temperature on ammonia emissions is mainly concentrated in the cold start stage. The influence of ambient temperature on ammonia emission is shown that the ammonia emissions of light-duty gasoline vehicles under ambient temperature conditions (14 and 23°C) are lower than those under low ambient temperature conditions (?7°C) and high ambient temperature conditions (35 and 40°C). The influence of TWC on ammonia emission is shown that ammonia is a by-product of the catalytic reduction reaction of conventional gas pollutants in the exhaust gas in the TWC. Under NEDC operating conditions and WLTC operating conditions, ammonia emissions after the catalyst are 45 times and 72 times that before the catalyst, respectively. In terms of ammonia emissions control strategy research, Pd/Rh combination can reduce NH3 formation more effectively than catalyst with a single Pd formula. Precise control of the engine's air-fuel ratio and combination with the optimized matched precious metal ratio TWC can effectively reduce ammonia emissions.  相似文献   
86.
As a proactive step towards understanding future waste management challenges, this paper presents a future oriented material flow analysis (MFA) used to estimate the volume of lithium-ion battery (LIB) wastes to be potentially generated in the United States due to electric vehicle (EV) deployment in the near and long term future. Because future adoption of LIB and EV technology is uncertain, a set of scenarios was developed to bound the parameters most influential to the MFA model and to forecast “low,” “baseline,” and “high” projections of future end-of-life battery outflows from years 2015 to 2040. These models were implemented using technology forecasts, technical literature, and bench-scale data characterizing battery material composition. Considering the range from the most conservative to most extreme estimates, a cumulative outflow between 0.33 million metric tons and 4 million metric tons of lithium-ion cells could be generated between 2015 and 2040. Of this waste stream, only 42% of the expected materials (by weight) is currently recycled in the U.S., including metals such as aluminum, cobalt, copper, nickel, and steel. Another 10% of the projected EV battery waste stream (by weight) includes two high value materials that are currently not recycled at a significant rate: lithium and manganese. The remaining fraction of this waste stream will include materials with low recycling potential, for which safe disposal routes must be identified. Results also indicate that because of the potential “lifespan mismatch” between battery packs and the vehicles in which they are used, batteries with high reuse potential may also be entering the waste stream. As such, a robust end-of-life battery management system must include an increase in reuse avenues, expanded recycling capacity, and ultimate disposal routes that minimize risk to human and environmental health.  相似文献   
87.
通过火灾模拟实验,研究电熨斗发生过热故障后底板的火灾痕迹特性。根据底板的温度分布,应用DTA、TG、SEM、EDS、硬度分析和金相分析等方法,系统分析、归纳、总结电熨斗底板火灾痕迹的材料性能变化规律。研究表明,过热故障电熨斗的火灾痕迹,在宏观形貌、硬度分布和显微组织特征等方面,均显著区别于火烧电熨斗的火灾痕迹。结果为火灾原因调查提供新的技术依据,可应用在火灾现场勘验,物证提取与鉴定工作中。  相似文献   
88.
Environmental regulations that grandfather existing plants, by not holding them to the same strict standards as new plants, may have the unintended consequence of retarding new investment. If new plants are cleaner, then this effect may increase pollution in the short run. I develop a dynamic model of a facility’s decisions over scrapping and abatement, which depend on capital depreciation, profitability shocks, and environmental policy. Using data from fossil fuel fired boilers at electric power plants, I estimate the structural parameters of the model and assess the impact of grandfathering in the Clean Air Act on sulfur dioxide emissions. Counterfactual policy simulations show that an increase in the stringency of performance standards would have led to a decrease in investment in new boilers. However, this does not lead to increased emissions, since there is less investment in dirtier coal boilers as compared to relatively cleaner oil or natural gas boilers.  相似文献   
89.
90.
Much academic research and industrial development explores new ways to create greener and environmentally friendlier chemicals and materials for a variety of applications. A significant part of this work focuses on the development, processing and manufacturing, recycling and disposal of green plastics, adhesives, polymer composites, blends and many other industrial products from renewable resources. Natural fibres offer the potential to deliver greater added value, sustainability, renewability and lower costs especially in the automotive industry. Further research involves the fibre crop production. The ever-increasing volume of scientific literature refers with enthusiasm to the potential of natural fibres in technological, economic and ecological terms. This enthusiasm tends to also expand to the areas of human life and socio-economic development for the fibre crop growers and their communities. However, there is very little debate or evidence to support statements about the assumed advantages for the affected population in rural areas. We argue that despite the predicted new boom in the demand of natural fibres, it is unlikely that this will represent a real improvement in the quality of life of crop fibre growers and their communities. This paper examines the experience of Mexico as a case study and argues that only through consistent political will and co-operation between governments, industry, scientists, consumer groups and local communities, as well as a suitable economic strategy such as local subsidies, a truly sustainable economic development, social equity and improved environmental quality will be achieved for tens of thousands of natural fibre growers.  相似文献   
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