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91.
In close-coupled gas atomization(CCGA), the influences of melt superheat on breakup process are fundamental to obtain desired or finer powder. Based on a series of Cu atomization experiment under different superheating conditions, the influences of melt superheat on breakup process were studied. Experimental results indicate that as the melt superheat is increased to 150, 200, 250 and 300 K, the mean particle size (D50) decreases consequently to 34.9, 32.3, 30.9 and 19.7 μm. Theoretical analysis reveals that the primary breakup and secondary breakup processes are close coupled, and the melt superheat radically influences the melt properties, and plays a crucial role on governing the filming process of primary breakup and the atomization modes of secondary breakup. There exists a strong nonlinear decrease of contact angle of melt to nozzle orifice wall when the superheat is increased fi'om 250 K to 300 K, leading to a marked fall of the film thickness formed in primary breakup, and D50 of copper powders is therefore sharply reduced. However, the log-normal distribution feature of particle size has not been substantially improved. 相似文献
92.
T. M. Morris 《Journal of the Institute of Brewing》1987,93(1):13-17
Haze measurements have been obtained for suspensions of polystyrenelatex particles of known diameter using two light scattering instruments which measure at angles of 90° and 13° respectively. The results agree well with the theory of light scattering and demonstrate the significant effects of particle size and angle of detection upon the instrumental values for haze. This information has been used to correlate the particle size distributions of a number of beers, as measured by Coulter Counter, with the corresponding, measured haze values. 相似文献
93.
94.
大中型风力发电机组可靠性研究 总被引:6,自引:2,他引:4
研究了大中型风力发电机组的可靠性,讨论了可靠性指标的分配,可靠性设计的四个重要方面、可靠性试验计算机模拟。 相似文献
95.
大型焦炉计算机优化控制系统 总被引:7,自引:2,他引:5
本文介绍一个大型焦炉计算机优化控制系统,它不仅实现了燃烧系统的DDC控制,而且完成了结焦终点的在线预报和以焦炉能耗最小为目标的优化控制。 相似文献
96.
97.
Effect of Particle Size on Monometallic and Bimetallic (Au,Pd)/C
on the Liquid Phase Oxidation of Glycerol 总被引:2,自引:0,他引:2
Nikolaos Dimitratos Jose Antonio Lopez-Sanchez David Lennon Francesca Porta Laura Prati Alberto Villa 《Catalysis Letters》2006,108(3-4):147-153
The influence of metal particle size of monometallic and bimetallic supported catalysts (Au, Pd, Au–Pd)/C was studied using
as a model reaction the liquid phase oxidation of glycerol. By tuning the metal particle size from 2 to 16 nm a progressive
decrease of activity and simultaneously an increase in the selectivity to sodium glycerate was observed. Moreover, the influence
of the temperature was studied and it was found that by increasing the temperature, only with a large particle size the formed
glycerate was retained and not over-oxidized to tartronate. 相似文献
98.
99.
大空域机动巡航导弹的模糊PID控制器设计 总被引:1,自引:1,他引:0
针对大空域机动巡航导弹下降转平飞过程中出现的强非线性特点.在俯仰通道设计了模糊PID双模控制方案。以高度误差和该误差变化量为输入.以高度误差为阀限.在高度误差较大时采用响应迅速的模糊控制器.较小时采用稳态精度较高的PID控制器。最后通过仿真表明通过该方案所控制的弹道符合方案弹道.满足设计指标要求。 相似文献
100.
It is shown, by means of Lagrangian momentum and power balances across the slug nose in slug flow, that the power dissipated due to sudden expansion of the fluid in the film immediately downstream of the slug nose is greater than the power lost due to viscous action at the pipe wall but that it may not be large enough to materially aid particle transport. This has the implication that sand transport in intermittent flow may be considered as transport in a hybrid flow of hydraulic conveying and stratified flow when the length of the mixing section at the slug nose is short compared to the length of the slug body. 相似文献