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141.
DYNAMIC LOAD CHARACTERISTICS OF ARRESTING HOOK SWINGING ALONG ARRESTING CABLE IN CARRIER-BASED AIRCRAFT 总被引:1,自引:0,他引:1
针对舰载机钩偏着舰时拦阻钩沿拦阻索侧向滑摆运动,运用仿真与理论分析结合的方法,通过调整拦阻钩侧向动载荷的振动频率范围,具体研究了飞机机身动载荷特性。结果表明,在2 Hz, 10 Hz,20 Hz 等振动频率附近,机身会受到严重的载荷情况。结论可供机体结构刚度、钩头减摆等性能优化设计参考。 相似文献
142.
143.
Na-A type zeolite (Na-A) pellet showed a greater oxygen selectivity than Na-A powder (Izumi, J. and M. Suzuki, Adsorption, submitted; Izumi, J. et al., Japan Patent Toku-Kou-Shou 62-026808 (1987)). It was considered that a water adsorption at calcination stage influenced a window diameter shrinkage to increase the oxygen selectivity. For the confirmation of an optimum preparation condition for the oxygen selectivity enhancement of Na-A pellet, an experiment of oxygen and nitrogen adsorption on calcined Na-A was undertaken with a small adsorbent column under a pressure swing adsorption (PSA) condition at a temperature from 298 K to 213 K. It was found that the secondary calcination (953–1033 K) after the water vapor adsorption provided a remarkable increase of the oxygen selectivity. At the optimum condition for calcined Na-A, the oxygen separation factor is greater than 6. Calcined Na-A has a potential to separate oxygen and nitrogen from air by PSA effectively. 相似文献
144.
145.
吸附分离技术在现代工业中的应用 总被引:7,自引:0,他引:7
概括介绍了吸附分离技术的发展,详细评述了吸附分离技术的最新进展和在现代工业中的应用,并预测了吸附分离技术未来的发展方向。 相似文献
146.
147.
The Newtonian gravitational constantG is determined by means of the swing time method at the Cave Laboratory of Center for Gravitational Experiment of Huazhong
University of Science and Technology. The result value ofG is (6.669 0 ± 0.001 6) × 10-11 m3·kg-1·s-2, which is consistent with the CODATA value of G obtained by Cohen and Taylor in 3σ.
Project supported by the National Natural Science Foundation of China (Grant Nos. 19425008 and 49674246). 相似文献
148.
149.
本文给出了主机运行中各线圈电压监测结果;在测出HL-1装置变压器的磁化曲线基础上,从几个不同位置测量了装置在放电过程中伏秒数随时间变化过程的初步结果。 相似文献
150.
Heungsoo Shin 《Adsorption》1995,1(4):321-333
Gas separation of a binary gas mixture by various pressure swing adsorption (PSA) cycles was studied by a numerical simulation in order to provide a guidance in selecting PSA cycles. PSA cycles considered in this study are 3, 4-step cycles for production of only one component and a cycle with pressure equalization for production of a light component. 4 and 5-step cycles for simultaneous production of both components of a binary gas mixture are also considered. Separation of a CH4/CO2 gas mixture with zeolite 5A was chosen as a case study. Performances of cycles were examined and compared in view of purity, recovery and productivity. Their relative advantages were discussed. Inclusion of a purging step to a 3-step cycle for production of only one component improves a cycle performance. Further performance improvement of a cycle for production of a light component can be achieved by employing pressure equalization. Sircar's 4-step cycle with a recycle of effluent shows the best performance in view of purity and recovery among cycles for simultaneous production of both components.Nomenclature
B
Langmuir adsorption constant, bar–1
-
C
concentration of sorbate in gas phase, mol/m3
-
D
defined by Eq. (7)
-
n
amount of sorbate in solid phase, mol/kg
-
n
s
monolayer amount adsorbed, mol/kg
-
P
pressure, bar
-
R
gas constant, J/mol K
-
T
temperature, K
-
t
time, s
-
U
effluent gas velocity, m/s
- z
height of one cell, m
-
bulk density of a bed, kg/m3
-
bed void fraction
-
A
CH4
-
B
CO2
-
H
high pressure feed step
-
P
purge step
-
R
heavy-component rinse step
-
i
cell number (i=1 toN) 相似文献