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在分析蓄热燃烧方法和现有蓄热式烤包器的基础上,结合莱钢炼钢厂钢包烘烤现状,研制开发了新的蓄热式空间燃烧烤包器。现场使用证明该烤包器具有节能、加热均匀和低污染排放等显著优点,具有广阔的应用前景。 相似文献
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Changes in climate, atmospheric carbon dioxide concentration and fire regimes have been occurring for decades in the global boreal forest, with future climate change likely to increase fire frequency--the primary disturbance agent in most boreal forests. Previous attempts to assess quantitatively the effect of changing environmental conditions on the net boreal forest carbon balance have not taken into account the competition between different vegetation types on a large scale. Here we use a process model with three competing vascular and non-vascular vegetation types to examine the effects of climate, carbon dioxide concentrations and fire disturbance on net biome production, net primary production and vegetation dominance in 100 Mha of Canadian boreal forest. We find that the carbon balance of this region was driven by changes in fire disturbance from 1948 to 2005. Climate changes affected the variability, but not the mean, of the landscape carbon balance, with precipitation exerting a more significant effect than temperature. We show that more frequent and larger fires in the late twentieth century resulted in deciduous trees and mosses increasing production at the expense of coniferous trees. Our model did not however exhibit the increases in total forest net primary production that have been inferred from satellite data. We find that poor soil drainage decreased the variability of the landscape carbon balance, which suggests that increased climate and hydrological changes have the potential to affect disproportionately the carbon dynamics of these areas. Overall, we conclude that direct ecophysiological changes resulting from global climate change have not yet been felt in this large boreal region. Variations in the landscape carbon balance and vegetation dominance have so far been driven largely by increases in fire frequency. 相似文献
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加快推进民族地区城乡公共服务一体化 总被引:1,自引:0,他引:1
由于城乡和区域发展不平衡所造成的深层次矛盾突出,民族地区在公共服务领域和其他地区还存在明显的差距。加快推进民族地区城乡公共服务一体化进程,其基本途径是统筹城乡发展,在加快转变经济发展方式中促进城乡一体化,以保障和改善民生为重点,以完善的制度安排和政策体系为保障,加大中央财政在教育、医疗卫生、社会保障、公共基础设施等方面对民族地区的扶持力度,创新社会管理,逐步形成覆盖城乡居民的基本公共服务体系。 相似文献
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