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931.
The objective is to know how the CO2 emits and how much the CO2 emits due to the cement manufacture in both direct and indirect ways with the increasing concerns about the global warming and the cement plants emitting huge CO2. A precise method to calculate CO2 emissions including three processes was established in this paper and a case study was provided. From the case of 23 typical plants in China, we can see the amount of CO2 emissions at the right level. The summary of CO2 emissions consists of emissions from raw materials, fuels and electricity. The average result of the 23 typical plants is 0.74 t CO2 per ton clinker in this study. Therefore, CO2 emissions from these typical cement plants were pictured and then measured. The creative point is that an approach provides a basic framework to identify various situations in different cement plants in China and other in the rest of the world. The framework would be useful in quantitatively evaluating CO2 emissions for government to know precisely CO2 emissions in the cement plants. 相似文献
932.
根据交通管理的需求,选择行车道作为道路网络的最小建模单元,提出了一种新的基于行车道交通路网模型。模型利用几何和逻辑这两种网络结构,实现了道路网络几何特征表达和拓扑连通关系的分离;利用两层路网结构实现道路网络的多尺度表达;最后应用该模型讨论了移动对象的时空管理并以实例对模型进行了验证。 相似文献
933.
随着我国铁路运输事业向着高速、重载的方向迅速发展.对铁路列车制动技术提出了更高的要求。HXN5型内燃机车是戚墅堰机车有限公司与美国通用电器公司共同合作的,对HXN5型内燃机车空气管路系统的掌握和了解对机车的运用及检修均有很大的帮助。 相似文献
934.
935.
研究了一类带有阻尼项的三维等熵可压缩欧拉方程组经典解局部存在性和弱解的整体存在性。一方面利用对称双曲型方程组解的存在性结论,将该方程组转化为对称双曲型方程组,得到了经典解的局部存在性;另一方面由新坐标的引入,该方程组转化为比较熟悉的p-系统,并通过Glimm格式证明了它的整体弱解的存在性。 相似文献
936.
AbstractThe evolution in type,size and shape of carbides in as-cast American Iron and Steel Institute(AISI) M2 high-speed steel before and after annealing were investigated.The micromechanism which was responsible for those changes was also analyzed and discussed.At the initial stage of reheating,metastable M2C-type carbide decomposed continuously.M6C-type carbide nucleated at the interface of M2C/γfirstly and grow from surface to center.Then MC-type carbide nucleated at both surface of M6C/M6C and inner of M6C.With the increasing decomposition of the metastable M2C-type carbide,the rod-shaped construction of eutectic carbide began necking,fracturing and spheroidizing gradually.Held enough time or reheated at higher temperature,particle-shaped product aggregated and grew up apparently,while secondary carbide precipitated in cell and grew up less sig- nificantly than the former.Based on the above microstructural observation,the thermodynamic mechanism for decomposition of M2C carbide,for spheroidization of products,and for the growth of particles were analyzed.The rate equations of carbides evolution were derived,too.It shows that the evolving rate is controlled by diffusion coefficients of alloy atoms,morphology of eutectic carbides and heating temperature. 相似文献
937.
Electron beam welding of in situ TiB2p reinforced aluminum composites was studied. The results show that no obvious pores or cracks is presented in the weld seam.
The grains in the weld seam are remarkably refined and TiB2 particles distribute much more homogeneously than that in base metal. The hardness values of fusion zone and heat affected
zone (HAZ) are both increased in comparison with that of base metal. There are no interface reactions between TiB2 particle and Al matrix. This results supply the evidence that the novel TiB2p reinforced aluminum composites can be well joined with the electron beam welding. 相似文献
938.
939.
建筑行业门槛低,市场竞争激烈,利润不断摊薄。施工企业面临严竣经营形势,唯有强化成本管理,增收节支,才能在经营活动中有所收获。该文通过对建筑公司在企业及项目部两级成本管理方面的制度、规则及策略进行分析,总结了施工企业在市场经济条件下成本管理方面的部分经验,对施工企业提高市场竞争力和经济效益将有一定的借鉴作用。 相似文献