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51.
The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) Everything is interconnected (and should usually stay that way), and (2) We can never do merely one thing. The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones.  相似文献   
52.
电动汽车与燃油汽车的环境指标比较   总被引:2,自引:0,他引:2  
郭文双  申金升  徐一飞 《交通环保》2002,23(2):21-23,30
对燃油汽车的尾气直接污染,尾气间接污染和噪声污染的环境指标进行了分析。比较了电动汽车与燃油汽车的同类环境指标,指出中国发展电动汽车对于改善环境的重要作用。  相似文献   
53.
电除尘器管状芒刺类电晕极电参数模拟计算   总被引:1,自引:0,他引:1       下载免费PDF全文
推导了不等线径、不等线距圆线组合电除尘器伏安特性计算关系,利用不等线径、不等线距圆线组合对管状芒刺类电晕极作了近似简化处理.采用静电场与电晕电场相叠加的办法建立了管状芒刺类电晕极电场分布的一种计算方法.与实验值对比表明,该方法的计算结果是可靠的.  相似文献   
54.
调查和研究了9种车型:轿车、出租车、摩托车、中型客车、小型面包车、大公共汽车、轻型货车、中型货车、重型货车的汽油和柴油的NOx,CO、HC、SO2、PM10污染排放量及分别在主干线、次干线、支路、街巷路中每条路段不同时间车流量密度及利用排放因子,求出每条路段机动车污染物排放量。同时分别汇总主干线、次干线、支路、街巷路中9种车型车流量密度及污染物排放量,最后估算出污染物排放总量。  相似文献   
55.
当今城市大气污染物中 6 0 %— 70 %来自机动车的排放 ,而其中很大部分是柴油车的排放。作者对柴油车在城市生活中的重要地位、对在用柴油车的技术改造措施和城市环境保护的其他举措进行了研究探讨 ,提出了一些具体方案  相似文献   
56.
广州市在用汽车排气检测执行新标准的初步分析   总被引:1,自引:0,他引:1  
在广州市机动车排气检测工作中,对在用汽车(指已上牌的汽车)在路检、抽检、复测和被举报冒黑烟车辆检测已经全面执行GB 18585-2005和GB 3847-2005国家新标准。文章对执行新标准实际工作中的技术问题和检测结果作了初步分析,并提出了相应的建议。  相似文献   
57.
Over the past decade, the emission standards and fuel standards in Beijing have been upgraded twice, and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles. Through the formulation and implementation of these policies, the emissions of carbon monoxide (CO), volatile organic compounds (VOCs), nitrogen oxides (NOx), and fine particulate matter (PM2.5) in 2019 were 147.9, 25.3, 43.4, and 0.91 kton in Beijing, respectively. The emission factor method was adopted to better understand the emissions characteristics of primary air pollutants from combustion engine vehicles and to improve pollution control. In combination with the air quality improvement goals and the status of social and economic development during the 14th Five-Year Plan period in Beijing, different vehicle pollution control scenarios were established, and emissions reductions were projected. The results show that the emissions of four air pollutants (CO, VOCs, NOx, and PM2.5) from vehicles in Beijing decreased by an average of 68% in 2019, compared to their levels in 2009. The contribution of NOx emissions from diesel vehicles increased from 35% in 2009 to 56% in 2019, which indicated that clean and energy-saving diesel vehicle fleets should be further improved. Electric vehicle adoption could be an important measure to reduce pollutant emissions. With the further upgrading of vehicle structure and the adoption of electric vehicles, it is expected that the total emissions of the four vehicle pollutants can be reduced by 20%-41% by the end of the 14th Five-Year Plan period.  相似文献   
58.
Objective: European car design regulations and New Car Assessment Program (NCAP) ratings have led to reductions in pedestrian injuries. The aim of this study was to evaluate the impact of improving vehicle front design on mortality and morbidity due to pedestrian injuries in a European country (Germany) and 2 countries (the United States and India) that do not have pedestrian-focused NCAP testing or design regulations.

Methods: We used data from the International Road Traffic and Accident Database and the Global Burden of Disease project to estimate baseline pedestrian deaths and nonfatal injuries in each country in 2013. The effect of improved passenger car star ratings on probability of pedestrian injury was based on recent evaluations of pedestrian crash data from Germany. The effect of improved heavy motor vehicle (HMV) front end design on pedestrian injuries was based on estimates reported by simulation studies. We used burden of disease methods to estimate population health loss by combining the burden of morbidity and mortality in disability-adjusted life years (DALYs) lost.

Results: Extrapolating from evaluations in Germany suggests that improving front end design of cars can potentially reduce the burden of pedestrian injuries due to cars by up to 24% in the United States and 41% in India. In Germany, where cars comply with the United Nations regulation on pedestrian safety, additional improvements would have led to a 1% reduction. Similarly, improved HMV design would reduce DALYs lost by pedestrian victims hit by HMVs by 20% in each country. Overall, improved vehicle design would reduce DALYs lost to road traffic injuries (RTIs) by 0.8% in Germany, 4.1% in the United States, and 6.7% in India.

Conclusions: Recent evaluations show a strong correlation between Euro NCAP pedestrian scores and real-life pedestrian injuries, suggesting that improved car front end design in Europe has led to substantial reductions in pedestrian injuries. Although the United States has fewer pedestrian crashes, it would nevertheless benefit substantially by adopting similar regulations and instituting pedestrian NCAP testing. The maximum benefit would be realized in low- and middle-income countries like India that have a high proportion of pedestrian crashes. Though crash avoidance technologies are being developed to protect pedestrians, supplemental protection through design regulations may significantly improve injury countermeasures for vulnerable road users.  相似文献   

59.
Nearly 130 years ago Holtzwart and von Meyer (1891) demonstrated by experiments that explosible dust clouds could be ignited by inductive electric sparks. Then more than half a century passed before the publication of the important quantitative research of Boyle and Llewellyn (1950) and Line et al. (1959). They worked with capacitive electric sparks and found that the minimum capacitor energies ½CU2 required for ignition of various dust clouds in air decreased substantially when a large series resistance, in the range 104–107 Ω, was introduced in the discharge circuit. When considering that the net energies of the sparks themselves were only of the order of 10% of the ½CU2 discharged, the minimum net spark energies required for ignition with a large series resistance were only a few per cent of the net energies required without such a resistance.Line et al. observed that the essential effect of increasing the series resistance, and hence increasing the discharge time of the sparks, was to reduce the disturbance of the dust cloud by the blast wave from the spark. This phenomenon was explored further by Eckhoff (1970, 2017), and subsequently by some simple experiments by Eckhoff and Enstad (1976). Franke (1974, 1977) and Laar (1980) confirmed the additional finding of Line et al. (1959) that the minimum ½CU2 for ignition is also substantially reduced by including a series inductance in the discharge circuit, rather than a series resistance. The basic reason is the same as with a large series resistance, viz. increased spark discharge time and hence decreased disturbance of the dust cloud by blast wave from the spark. For this reason inclusion of an appreciable series inductance in the spark discharge circuit is an essential element in current standard MIE test methods.In experiments with spark ignition of transient dust clouds produced by a blast of air in a closed vessel, it is necessary to synchronize the occurrence of the spark with the formation of the dust cloud. The precision required from this type of synchronization is typically of the order of 10 ms, which can be obtained even by mechanical arrangements, such as rapid change of spark gap length, or of the distance between two capacitor plates. The present paper reviews some methods that have been/are being used for achieving adequate synchronization of dust cloud appearance and spark discharge. Some current standard experimental methods for determining MIEs of dust clouds experimentally have also been reviewed. The same applies to some theories of electric-spark ignition of dust clouds.At the end of paper some suggestions for possible future modifications of current standard methods for measuring MIEs of explosible dust clouds are presented. With regard to justifying significant modifications of existing standard methods, the “bottom line” is, as quite often in many connections, that any modifications should be based on realistic cost/benefit evaluations.  相似文献   
60.
Objective: This study aimed to understand the awareness, riding behaviors, and legislative attitudes of electric bike (e-bike) users and non-e-bike road users toward e-bikes in Tianjin, a municipality in China.

Methods: This cross-sectional investigation included 2 components. The field survey was conducted in 9 districts (4 urban and 5 rural) from 2015 to 2017. Adult participants were interviewed using a street intercept method. The online survey was conducted using the WeChat social platform. A series of questions related to awareness and practice of e-bike safety-related issues was asked.

Results: A total of 16,859 interviews were completed, including 1,653 (794 e-bike users and 859 other road users) in-person interviews by field survey and 15,206 (4,426 e-bike users and 10,780 other road users) by online survey. Except for ignoring a red light when making a left turn (P?=?.000) and waiting across the white line at a red light (P?=?.000), which e-bike users were lower than other road users, there were no significant differences between e-bike users and other road users in regards to the correct awareness rate of riding in the opposite direction, riding in a motor vehicle lane, running red lights, jaywalking, speeding, carrying adult passengers, and riding on the expressway (P?>?.05). In addition, 74.2% of e-bike users considered helmet use necessary (P?=?.000) and 54.7% thought that installing a windshield is wrong (P?=?.000), which was higher than other road users (49.1 and 48.4%, respectively). Other road users had greater awareness than e-bike users regarding whether turning left at a red light is wrong (91.7 vs. 85.1%), waiting across the white line when the light is red is wrong (86.6 vs. 75.9%), lighs should be turned on at night (94.8 vs. 90.3%). Correct practices were far behind awareness in all kinds of violation behaviors (P?=?.000) among e-bike users in the field survey. The rate of public support for legislation including those who very much support and support legislation was 93.34% in the field survey and 87.68% in the online survey.

Conclusions: E-bike users had lower correct awareness rate than other road users regarding e-bike violation behaviors but were more concerned about safety protection than other road users. E-bike users’ correct practices were far behind their awareness for all kinds of violation behaviors. Public education on the traffic law needs to be strengthened among e-bike users. The public strongly supported special regulations for e-bike use, such as helmet use.  相似文献   
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