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51.
对循环流化床在脱硝、脱硫和除尘等方面环保技术路线进行了分析,权衡各项技术的利弊及经济因素,结合新颁布的火电厂大气污染物排放标准(GB 13223—2011),做出如下建议:半干旋转喷雾法脱硫工艺(SDA)和SCR结合使用后,氮氧化物的脱除效率可达到95%,循环流化床中高灰分的环境不适合使用SCR,SNCR的脱除效率虽然相对较低,但是通过调整还原剂的停留时间和与烟气的混合程度,脱硝效率可达70%以上,完全可以满足新环保标准的要求;石灰石-石膏湿法脱硫技术成熟,脱硫效率高,负荷适应性好,在循环流化床炉内脱硫的基础上外加该工艺,可以保证足够的脱硫效率;电袋组合式除尘器发挥了两种除尘器的技术优势,可以达到新标准的要求。 相似文献
52.
Miroslav Trnka Petr Hlavinka Mikhail A. Semenov 《Journal of the Royal Society Interface》2015,12(112)
Ways of increasing the production of wheat, the most widely grown cereal crop, will need to be found to meet the increasing demand caused by human population growth in the coming decades. This increase must occur despite the decrease in yield gains now being reported in some regions, increased price volatility and the expected increase in the frequency of adverse weather events that can reduce yields. However, if and how the frequency of adverse weather events will change over Europe, the most important wheat-growing area, has not yet been analysed. Here, we show that the accumulated probability of 11 adverse weather events with the potential to significantly reduce yield will increase markedly across all of Europe. We found that by the end of the century, the exposure of the key European wheat-growing areas, where most wheat production is currently concentrated, may increase more than twofold. However, if we consider the entire arable land area of Europe, a greater than threefold increase in risk was predicted. Therefore, shifting wheat production to new producing regions to reduce the risk might not be possible as the risk of adverse events beyond the key wheat-growing areas increases even more. Furthermore, we found a marked increase in wheat exposure to high temperatures, severe droughts and field inaccessibility compared with other types of adverse events. Our results also showed the limitations of some of the presently debated adaptation options and demonstrated the need for development of region-specific strategies. Other regions of the world could be affected by adverse weather events in the future in a way different from that considered here for Europe. This observation emphasizes the importance of conducting similar analyses for other major wheat regions. 相似文献
53.
Employing pretreatment is a pressing need for preparing anticorrosive coatings on carbon steels. However, conventional pretreatments are usually based on Cr, P and some other toxic elements, which are harmful to human body. For this reason, green and environmental techniques attract more and more attention. In this paper, plasma electrolytic oxidation (PEO) process was used as a pretreatment to fabricate an underlayer for the organic coating on low carbon steel. The anticorrosive performance of the organic coated samples with and without PEO pretreatment was studied by potentiodynamic polarization, ac/dc/ac electrochemical impedance spectroscopy, salt spray and immersion tests, respectively. Results show that the PEO process produces an oxide layer with porous and rough surface structure on the low carbon steel substrate. The porous and rough PEO layer is beneficial for enhancing the adhesion strength and thickness of the organic topcoatings. The organic coated sample with PEO pretreatment exhibits improved corrosion resistance and longer service life in corrosive environment compared to that without PEO pretreatment. 相似文献
54.
55.
随着我国环境保护法规《大气污染防治法》的修订和《涂料征收消费税通知》的公布,探讨了其对船舶涂料企业的冲击及其应对措施。 相似文献
56.
《Energy Policy》2015
This article sounds the alarm that a significant build-out of efficient lighting and renewable energy technologies may be endangered by shortages of rare earths and rare earth permanent magnets. At the moment, China is the predominant supplier of both and its recent rare earth industrial policies combined with its own growing demand for rare earths have caused widespread concern. To diversify supplies, new mining—outside of China—is needed. But what many observers of the “rare earth problem” overlook is that China also dominates in (1) the processing of rare earths, particularly the less abundant heavy rare earths, and (2) the supply chains for permanent magnets. Heavy rare earths and permanent magnets are critical for many renewable energy technologies, and it will require decades to develop new non-Chinese deposits, processing capacity, and supply chains. This article clarifies several misconceptions, evaluates frequently proposed solutions, and urges policy makers outside of China to undertake measures to avert a crisis, such as greater support for research and development and for the cultivation of intellectual capital. 相似文献
57.
文章从我国消防法制建设的现状出发,简要介绍了现行的消防法律法规,并详细解读了其现存问题,最后分别从消防法制建设与消防监督两个角度提出了发展对策,以期能为改善我国现阶段的消防法制建设和消防监督体系带来一定的参考意见. 相似文献
58.
59.
随着大数据和云计算的技术的深入应用,人工智能时代的机器学习和深度学习更需要日益增长的数据,因此数据安全与隐私保护变得更加迫切。本文介绍人工智能的定义以及特征,探究数据安全和隐私保护现状,分析数据安全和隐私保护面临的诸多问题,并提出在人工智能时代对数据安全和隐私保护的措施。 相似文献
60.
随着信息时代的迅速发展,云计算数据访问安全已经成为了用户最关心的问题。身份认证技术是确保参与者在开放的网络环境中实现安全通信的一种重要手段,如何利用身份认证技术为云环境安全保驾护航,成为学者研究的热点。文中通过公钥基础设施(Public Key Infrastructure,PKI)颁发CA证书以在不同云服务间建立信任,将多个采用身份密码体制(Identity-Based Encryption,IBE)的云联合起来;采用分层身份加密体系,引入共享密钥技术,通过选取成环结构,提出一种PKI-IBE混合认证模型方案,并对方案的安全性进行分析,从理论上证明了云环境下PKI-IBE(Public Key Infrastructure-Identity-Based Encryption)同层成环模型提供服务的可行性。同时文中设计了一种基于该模型的签密技术,通过公私密钥对实现云内认证以及跨云认证。安全性理论证明与性能分析表明,该方案在计算量稍增加的前提下,保证了足够的安全性,更加满足云环境下的用户分属不同云域的认证以及用户安全访问的需求,有效解决了云环境中数据访问的安全问题。 相似文献