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71.
近年来国内兴起了煤制天然气建设热潮,但可供参考经验不多。本文结合煤制天然气工厂建设经验,介绍了面向工业用户、面向城镇用户和面向综合用户三类工厂,简述了“从煤矿到煤制天然气工厂再到城镇用户”供应链存在的“煤化工生产装置要求安、稳、长、满、优运行与用户用气量不均衡之间的矛盾”和“煤化工生产装置阶段性停产必然性与用户要求供气不间断之间的矛盾”,指出了保证连续稳定供气是工厂建设的首要任务,解决或缓解供应链上的主要矛盾是建设的关键问题;分析了影响供应链上系统运行的因素,表明工厂首先要有明确的定位,煤源是工厂设计和运行的基础,采用可靠技术、本地化装备、多系列装置有利于工厂的优化运行和快速消除故障;提出应从总体设计开始设计全厂信息化并系统集成,安全环保设施和剩余物质管理要考虑规范升级对策,并高度重视由于量的变化所带来的问题;与利益相关者的关系非常重要。综合考虑资源、市场、环境和政策来制定建设原则。 相似文献
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Polyaluminocarbosilane (PACS) was synthesized directly by the one‐pot reaction of polydimethylsilane (PDMS) with aluminum acetylacetonate [Al(acac)3] in an autoclave. In this closed system, all the aluminum in Al(acac)3 was converted into PACS. Therefore, the content of aluminum could be readily controlled quantitatively. On the basis of Fourier transform infrared, 1H‐NMR, 13C‐NMR, 29Si‐NMR, and 27Al magic‐angle spinning NMR analysis, the reaction mechanism was proposed as follows: PDMS dissociated during pyrolysis to generate silicon free radicals, and then they reacted with Al(acac)3 to yield PACS containing (Si? O)nAl groups (n = 4, 5, or 6). Meanwhile, these reactions resulted in the cleavage of O? C and/or O?C bonds in Al(acac)3. Some of the free‐radical fragments generated by this cleavage continued to react with the silicon free radicals and were incorporated into the structural units of PACS; the rest of them may have been converted into small oxygen‐containing compounds, which were removed in the subsequent processing after the reactions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
73.
基于GT-Power的LPG燃气组分对发动机排放影响的研究 总被引:2,自引:1,他引:2
通过建立单缸点火式LPG发动机在GT-Power中仿真,来研究LPG组分及其比例对发动机排放的影响.仿真实验表明,LPG组分对污染物的排放有重要的影响.随着丁烷比例的增加,CO和HC的排放增加,而NO_x减少;其中,CO、HC排放最少的是Fuel 1#,NO_x的排放最低的是Fuel 3#;考虑到综合排放性能和动力性的同时,丙烷与丁烷比例为7:3时最佳. 相似文献
74.
采用等离子旋转电极雾化技术(plasma rotating electrode processing,PREP)制备出纯W和W-La合金球形粉末,对比分析了2种类型粉末的化学成分、形貌、物理性能、缺陷和粒度分布。结果表明:PREP法制备的球形纯W粉末表面光滑、球形度高,小于106μm粉末的收得率为70%。在棒料中加入La2O3后,大部分La2O3在PREP过程中挥发,残余的La2O3优先附着于液滴表面,降低了的液态金属钨的表面张力,将小于106μm粉末的收得率提升至90%;但是,表面张力的降低同时也导致W-La合金粉末表面出现少量缺陷。La2O3提高粉末收得率的现象为研究提高PREP技术粉末收得率提供了新思路。 相似文献
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Yixuan Jia Christoph A. Spiegel Alexander Welle Stefan Heißler Elaheh Sedghamiz Modan Liu Wolfgang Wenzel Maximilian Hackner Joachim P. Spatz Manuel Tsotsalas Eva Blasco 《Advanced functional materials》2023,33(39):2207826
Manufacturing programmable materials, whose mechanical properties can be adapted on demand, is highly desired for their application in areas ranging from robotics, to biomedicine, or microfluidics. Herein, the inclusion of dynamic and living bonds, such as alkoxyamines, in a printable formulation suitable for two-photon 3D laser printing is exploited. On one hand, taking advantage of the dynamic covalent character of alkoxyamines, the nitroxide exchange reaction is investigated. As a consequence, a reduction of the Young´s Modulus by 50%, is measured by nanoindentation. On the other hand, due to its “living” characteristic, the chain extension becomes possible via nitroxide mediated polymerization. In particular, living nitroxide mediated polymerization of styrene results not only in a dramatic increase of the volume (≈8 times) of the 3D printed microstructure but also an increase of the Young's Modulus by two orders of magnitude (from 14 MPa to 2.7 GPa), while maintaining the shape including fine structural details. Thus, the approach introduces a new dimension by enabling to create microstructures with dynamically tunable size and mechanical properties. 相似文献
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We studied the problem of QoS guarantee for differentiated services. A two-level hierarchical scheduling framework was deployed to separate QoS metrics. Due to its desirable property of minimizing the maximum packet lateness, the Earliest Deadline First (EDF) scheduling was adopted to provide the in-class scheduling for the time-sensitive traffic. We employed an EDF scheduler combined with an active buffer management scheme (CHOKe) to improve the fairness of resource allocation and to maintain a good delay performance for real-time applications. Simulation results showed that the proposed scheme can achieve a better delay performance and make a more fair bandwidth allocation between the real-time TCP and UDP connections than the First Come First Served (FCFS) scheduling with the drop-tail buffer management which is commonly deployed in traditional IP routers. 相似文献