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51.
综述了国内外锂离子动力电池充电方式所经历的各个发展阶段和最新的成果,并阐述了每种充电模式的优缺点和对电池寿命的影响,着重介绍了快速充电方式的发展历程,总结出其发展的规律。在众多的充电模式中,脉冲充电和快速智能充电由于省时、高效和寿命长等优点已被大量研究和应用。本研究对锂动力电池的实际应用具有重要的指导意义。  相似文献   
52.
To support the development of policies that reduce greenhouse gas (GHG) emissions by encouraging reduced travel and increased use of efficient transportation modes, it is necessary to better understand the explanatory effects that transportation, population density, and policy variables have on passenger travel related CO2 emissions. This study presents the development of a model of CO2 emissions per capita as a function of various explanatory variables using data on 146 urbanized areas in the United States. The model takes into account selectivity bias resulting from the fact that adopting policies aimed at reducing emissions in an urbanized area may be partly driven by the presence of environmental concerns in that area. The results indicate that population density, transit share, freeway lane-miles per capita, private vehicle occupancy, and average travel time have a statistically significant explanatory effect on passenger travel related CO2 emissions. In addition, the presence of automobile emissions inspection programs, which serves as a proxy indicator of other policies addressing environmental concerns and which could influence travelers in making environmentally favorable travel choices, markedly changes the manner in which transportation variables explain CO2 emission levels.  相似文献   
53.
Several electrification systems based on renewable energy power sources (first of all, solar energy) are discussed in respect to their applicability to railway transport and, in particular, to suburban electric trains. Two systems are considered with basic technical details and economic estimation, both including the onboard bank of batteries and the photovoltaic converters (PVC) of solar energy for compensation of energy expenses, which could be positioned either on stations or on wagon's roofs. Sun‐tracking systems and their effect on the solar energy conversion efficiency are discussed in application to stationary and moving PVC platforms. An analysis made shows that introduction of the “green” systems discussed will not only have positive ecological impact, but also can bring a notable economical effect even with today's components, while it could be considerably greater with the usage of new PVCs, which are being developed by the authors. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
54.
Lithium traction batteries are a key enabling technology for plug-in electric vehicles (PEVs). Traction battery manufacture contributes to vehicle production emissions, and battery performance can have significant effects on life cycle greenhouse gas (GHG) emissions for PEVs. To assess emissions from PEVs, a life cycle perspective that accounts for vehicle production and operation is needed. However, the contribution of batteries to life cycle emissions hinge on a number of factors that are largely absent from previous analyses, notably the interaction of battery chemistry alternatives and the number of electric vehicle kilometers of travel (e-VKT) delivered by a battery. We compare life cycle GHG emissions from lithium-based traction batteries for vehicles using a probabilistic approach based on 24 hypothetical vehicles modeled on the current US market. We simulate life-cycle emissions for five commercial lithium chemistries. Examining these chemistries leads to estimates of emissions from battery production of 194–494 kg CO2 equivalent (CO2e) per kWh of battery capacity. Combined battery production and fuel cycle emissions intensity for plug-in hybrid electric vehicles is 226–386 g CO2e/e-VKT, and for all-electric vehicles 148–254 g CO2e/e-VKT. This compares to emissions for vehicle operation alone of 140–244 g CO2e/e-VKT for grid-charged electric vehicles. Emissions estimates are highly dependent on the emissions intensity of the operating grid, but other upstream factors including material production emissions, and operating conditions including battery cycle life and climate, also affect life cycle GHG performance. Overall, we find battery production is 5–15% of vehicle operation GHG emissions on an e-VKT basis.  相似文献   
55.
按照键合图的规则,分别建立了蓄电池等效电路的键合图模型和冷却系统的键合图模型,然后将电系统和热系统耦合在一起,实现了蓄电池系统的键合图模型,最后建立了蓄电池的数学模型和仿真模型,并实现了动态仿真。  相似文献   
56.
免维护电池不等于不需要维护。本文介绍了用内阻法测量蓄电池故障的原理及方法,并通过试验得出:根据免维护电池内阻值的变化可预测出机车蓄电池的故障。  相似文献   
57.
Ships of opportunity have been used to investigate ocean–atmosphere CO2 fluxes in the English Channel and Southern Bight of the North Sea. Continuous underway measurements of the fugacity of seawater carbon dioxide (fCO2sw), chlorophyll, temperature and salinity have been performed along 26 transects during the spring and autumn periods. The spatial fCO2sw distribution along the Channel and Southern Bight is modulated by the photosynthetic activity, temperature changes and water mixing between inputs from the North Atlantic Ocean and riverine discharges. The seasonal variability of fCO2sw is assessed and discussed in terms of the biology and temperature effects, these having similar impacts. The variation of fCO2sw shows similar interannual patterns, with lower values in spring. The annual average of air–sea CO2 fluxes places the English Channel as neutral area of CO2 uptake. The spring and autumn data allow differentiating between distal and proximal continental areas. The Southern Bight shows a tendency towards net CO2 uptake on the distal continental shelf, whereas the Scheldt and Thames Plumes show a CO2 source behaviour on the proximal continental shelves.  相似文献   
58.
郑晓鹏 《中国造船》2007,48(B11):297-302
CO2减排是国际关注的热点问题。将CO2注入地下地质构造永久封存是CO2减排的有效途径。挪威Sleipner气田盐水层CO2封存工程是世界上第一个完全为了对CO2进行地质封存而实施的商业项目,为CO2的海上捕集、地质存储及其监测提供了极其宝贵的经验。详细介绍Sleipner气田海上平台MDEA法天然气分离CO2技术及CO2高压密相回注工艺,为我国南海莺歌海盆地天然气田伴生二氧化碳的埋存和利用提供参考。  相似文献   
59.
刘志刚 《船海工程》2006,35(6):119-121
介绍蓄电池分类及特点,放电浓度、硫酸浓度、温度等是影响船用铅酸蓄电池使用寿命的主要因素;提出在日常使用中要常检查铅酸蓄电池在支架上的固定螺栓,保持蓄电池盖上的气孔畅通无阻等正确的维护方法。  相似文献   
60.
锰与工人心血管健康   总被引:8,自引:0,他引:8  
临床研究和职业流行病学调查发现,锰作业工人心电图异常率明显增高,其中以窦性心动性缓、过速及不齐为主,并有左室肥大和ST-T改变。锰作业女工心率加快,P-R间期缩短,锰中毒病人有体位性低血压。锰作业工人低舒张压检出率增高,舒张压均值明显降低,以青工及女工表现更为突出,提示猛对工人有明显的心血管效应。本文对锰与工人心血管健康研究的进一步发展提出了展望。  相似文献   
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