Unlike other rockets, Falcon 9's upper and lower stages do not use explosive bolts to separate mid-flight.

不同于其他火箭，飞行中，猎鹰9号的上下级不使用爆炸螺栓分离。

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In order to adjust Upper Jingjiang stretch fluvial regime and predict its change tendency after completion of TGP, a physical model study on Upper Jingjiang stretch was carried out at various stages.

为了调整上荆江河势及预测三峡工程兴建后上荆江河势变化趋势，分阶段进行了上荆江实体模型河势调整试验和河床冲刷试验研究工作。

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The upper leaves of flue_cured tobacco CV. NC89, K326, RG11 were sliced, and their changes of thickness and dissecting structure were observed from the stages of yellowing to color fixing.

以烤烟品种NC89、K326、RG11的上部叶为材料，对变黄期至定色期烟叶厚度及解剖结构的变化进行了切片观察。

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This architecture also enables NASA to leverage existing capabilities and lower development costs by using liquid hydrogen and liquid oxygen for both the core and upper stages.

ENGADGET: NASA's Space Launch System to rocket into deep space, unravel the universe's mysteries (video)

Fulham enjoyed the upper hand in the opening stages and mustered two penalty shouts inside the first 10 minutes.

BBC: Fulham 2-1 Wolves