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181.
针对秦皇岛市能源消耗中清洁能源比重较小,不利于城市环境改善的状况,提出了推行"以电代煤"来优化能源结构,改善城市环境.并对秦皇岛市"以电代煤"潜力进行了分析,提出了在居民生活、农村、商饮业、党政机关和公用事业单位推行"以电代煤"的措施.  相似文献   
182.
Bio-effects of static magnetic fields on cell growth and cell death have been investigated in suspension-cultured tobacco cells as undifferentiated, embryonic plant cell model. The cells in their logarithmic growth phase were exposed to static magnetic field with the magnitudes of 10 mT and 30 mT for 5 h/day. Exposure to static magnetic field ceased the growth and caused an increase in cell death of exposed tobacco cells compared to those cells which were not treated with the field. Promotion of cell death was accompanied by a harmonized increase in the activity of peroxidase and increase of lignifcation of cell walls.  相似文献   
183.
含氧氢气钢瓶释放过程危险性分析及处置   总被引:1,自引:1,他引:1  
针对一起空气误充入氢气钢瓶而导致使用时发生多起爆炸的事故,详细分析了氢氧混合气钢瓶在释放过程中的主要危险性,对释放过程中最可能存在的点火源即静电的产生机理及静电的放电条件进行了详细的论述,应用TNT当量法对可能发生的氢气钢瓶爆炸事故的破坏强度进行了估算。针对爆炸事故的高危险性,制定了以电机作为开阀动力的远距离放空方案,并提出了接地、洒水增湿等预防静电产生的有效措施,综合考虑冲击波超压伤害和人员操作的方便,确定了合理的安全操作距离,为防止爆炸产生的碎片对周围人员、建筑的伤害,在释放场所周围及人员操作场所设置了沙包墙作为防爆掩体。  相似文献   
184.
静电灾害已成为现代工业安全生产活动的主要危害之一 . 通过对易燃易爆性液体及气体 静电产生机理的分析 , 结合防静电、防爆安全检测工作实际 , 指出了加油站静电产生的三个 主要环节 , 并提出了相应的防护技术和措施 .  相似文献   
185.
论油田电力调度安全运行管理途径   总被引:2,自引:0,他引:2  
从5个方面论述了如何做好电力调度安全运行的管理工作,并且提出和分析了各个方面在电网运行中所起的作用和意义.  相似文献   
186.
Modern Biomass Conversion Technologies   总被引:4,自引:2,他引:4  
This article gives an overview of the state-of-the-art of key biomass conversion technologies currently deployed and technologies that may play a key role in the future, including possible linkage to CO2 capture and sequestration technology (CCS). In doing so, special attention is paid to production of biofuels for the transport sector, because this is likely to become the key emerging market for large-scale sustainable biomass use. Although the actual role of bio-energy will depend on its competitiveness with fossil fuels and on agricultural policies worldwide, it seems realistic to expect that the current contribution of bio-energy of 40–55 EJ per year will increase considerably. A range from 200 to 300 EJ may be observed looking well into this century, making biomass a more important energy supply option than mineral oil today. A key issue for bio-energy is that its use should be modernized to fit into a sustainable development path. Especially promising are the production of electricity via advanced conversion concepts (i.e. gasification and state-of-the-art combustion and co-firing) and modern biomass derived fuels like methanol, hydrogen and ethanol from ligno-cellulosic biomass, which can reach competitive cost levels within 1–2 decades (partly depending on price developments with petroleum). Sugar cane based ethanol production already provides a competitive biofuel production system in tropical regions and further improvements are possible. Flexible energy systems, in which biomass and fossil fuels can be used in combination, could be the backbone for a low risk, low cost and low carbon emission energy supply system for large scale supply of fuels and power and providing a framework for the evolution of large scale biomass raw material supply systems. The gasification route offers special possibilities to combine this with low cost CO2 capture (and storage), resulting in concepts that are both flexible with respect to primary fuel input as well as product mix and with the possibility of achieving zero or even negative carbon emissions. Prolonged RD&D efforts and biomass market development, consistent policy support and international collaboration are essential to achieve this.  相似文献   
187.
Renewable generating technologies offer an effective means for climate change mitigation. Policy makers, however, are wary because of the widespread perception that these technologies cost more than conventional alternatives so that increasing their deployment will raise overall electricity generating costs. Energy planning represents an investment-decision problem. Investors commonly evaluate such problems using portfolio theory to manage risk and maximize portfolio performance under a variety of unpredictable economic outcomes. Energy planners need to similarly abandon their reliance on traditional, “least-cost” stand-alone kWh generating cost measures and instead evaluate conventional and renewable energy sources on the basis of their portfolio cost – their cost contribution relative to their risk contribution to a mix of generating assets. Energy security generally focuses on the threat of abrupt supply disruptions. This paper suggests a more profound aspect: mitigating fossil price volatility. An extensive body of research indicates that fossil volatility significantly disrupts the economies of consuming nations, potentially exacting hundreds of billions of dollars from the US and EU economies alone. Energy security is reduced when countries hold inefficient portfolios that are needlessly exposed to fossil price risks. This paper describes essential portfolio-theory ideas and uses three case studies to illustrate how electricity-generating mixes can benefit from additional shares of wind, geothermal and other renewables. Compared to existing, fossil-dominated mixes, efficient portfolios reduce generating cost while including greater renewables shares in the mix thereby enhancing energy security. Though counter-intuitive, the idea that adding more costly renewables can actually reduce portfolio-generating cost is consistent with basic finance theory. An important implication is that in dynamic and uncertain environments, the relative value of generating technologies must be determined not by evaluating alternative resources, but by evaluating alternative resource portfolios.  相似文献   
188.
用甲苯直接萃取酸化后尿中的除草醚,以气相色谱法测定。方法的最低检测限为2μl/l;精密度为4.7%;回收率为95%。  相似文献   
189.
针对原油贮罐工程施工中的用电问题,提出改进安全用电的应对措施.  相似文献   
190.
“以电代煤”环境效益分析   总被引:1,自引:0,他引:1  
目前 ,我国只有约 1 /3的煤用于发电 ,远低于发达国家的水平。要改善我国特别是城市大气环境状况 ,实行“以电代煤”是一条最有效的途径。本文以上海、北京、柳州等城市为例 ,分析了“以电代煤”的环境效益 ,并指出 ,使用电力作为最终消费方式 ,最清洁、方便 ,效率最高 ,也最易于控制。  相似文献   
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