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湖南省酸雨现状与成因分析 总被引:1,自引:0,他引:1
湖南省是地处中南的酸雨污染严重区域。本文依据湖南省1993—1999年监测酸雨的数据资料,对湖南省酸雨的现状特征作了简要的阐述,对湖南省酸雨的成因进行了较为系统的分析,并对酸雨的发展趋势进行了预测,初步提出了一些酸雨防治对策。 相似文献
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Historical change of heavy metals in urban soils of Nanjing, China during the past 20 centuries 总被引:5,自引:0,他引:5
Two typical areas, including once commercial and residential quarters of Nanjing, China, were studied by investigating soil properties especially heavy metals of soils in various cultural layers formed in different Chinese Dynasties. The age of the soil profiles was dated by both archaeological and 14C chronological methods. The results showed that urban soils in the old commercial/workshop quarter of Nanjing were generally contaminated by heavy metals Cu, Zn, Pb, but their concentration levels varied significantly among the cultural layers formed in different dynasties. The substantial increase of heavy metals appeared in three historical periods, i.e., South Dynasty (222-589 AD), the earlier Ming (1368-1644 AD) and the late Qing (1644-1912 AD) in one area. The tremendous input and storage of heavy metals in soils was explained by the primitive smelting and the strengthened metal processing activities, which might be due to the requirement of weapon making or other industries, in the changing social conditions of the corresponding periods. Soils in the once noble political, cultural centers did not show significant increase of heavy metals. The difference in the distribution pattern of heavy metals revealed the contrasting history of the site uses. The change of contaminant level in soils is believed to be a reflection of various human activities in the city during the past 20 centuries. 相似文献
776.
Bing Xin Gong 《International Journal of Sustainable Engineering》2014,7(3):194-199
The world is facing an energy and climate crisis. Globally, the energy sector emits 26 billion tonnes of CO2 each year, and electricity production alone accounts for 41% of emissions (European Wind Energy Association. 2008. Pure Power: Wind Energy Scenarios up to 2030. European Wind Energy Association. p. 6). Currently, reducing CO2 emissions and curbing climate change have become global priorities, and we only have a narrow window of time left in which to act. The new type of refrigerator can offer an immediate and concrete solution to the many energy and climate challenges that we are facing. This is an account of a new type of refrigerator and its cycle for use in the refrigeration industry. For its cycle, the working substance is air or other gases; its cycle is very similar to that of the reverse Brayton cycle (Hou, Y., Zhao, H. L., Chen, C. Z., and Xiong, L. Y. 2006. “Developments in Reverse Brayton Cycle Cryocooler in China.” Cryogenics 46 (5): 403–407). In the cycle of the new type of refrigerator, the isochoric exothermic process and the isothermal exothermic compression process replace the isobaric exothermic compression process of the reverse Brayton cycle. The new type of refrigerator can produce a net electrical energy, and it is not a perpetual motion machine, because the environmental enthalpy and atmospheric pressure can be utilized as the external energy sources, which cannot be performed by any other conventional refrigerators; therefore, the reliability and significance of this new type of refrigerator is self-evident. 相似文献
777.
BingXin Gong 《International Journal of Sustainable Engineering》2016,9(5):345-352
This is a new technique for operating a Stirling heat engine. Theoretically, its thermal efficiency should be greater than 100%. However, it does not violate the first and second laws of thermodynamics; it is not a perpetual motion engine, because the atmospheric pressure can be utilized as the external energy source, which no other existing heat engines can do. This means that the new type of heat engine can offer an immediate and concrete solution to the many energy and climate challenges that we are facing; therefore the reliability and significance of this new type of Stirling heat engine is self-evident. 相似文献
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大力发展循环经济促进区域经济持续发展 总被引:1,自引:0,他引:1
党中央在科学总结国内外发展经验教训和充分吸收人类文明进步成果的基础上,提出了科学发展观。这是对经济、社会、自然发展规律认识的不断深化,是发展观念上的伟大创新,是对马克思主义发展观的最新贡献。从某种意义上讲,科学发展观源于可持续发展战略,可持续发展又源于环境保护。大力发展循环经济,是落实科学发展观的现实载体,是促进区域经济持续发展的必然途径,是调整结构、走新型工业化道路的战略选择。循环经济作为一种新的技术范式,一种新的生产力发展方式,为实施新型工业化开辟了新的道路。发展循环经济,就是要用循环经济理念指导和规… 相似文献
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高层建筑火灾防烟空气幕的实验研究 总被引:9,自引:4,他引:9
通过分析高层建筑火灾时引起烟气流动的因素 ,建立了高层建筑火灾时防烟空气幕流量、吹风口宽度和吹风口的射流速度的计算模型。通过实验研究 ,验证了理论计算的正确性 相似文献