The elevator model was made by using devices such as limit switch, nixie tube, direct current motor.

采用限位开关、按钮、数码管、直流电机等器件实际制作。

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This paper established the internal ballistics equation for the high-low pressure launcher with tandem construction when the rocket motor is ignited in the launch tube.

本文建立了火箭发动机在管内点燃情况下，串联结构的高低压无后座力发射器的内弹道方程，并对试验弹进行了数值计算。

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Neural stem cells can now be coaxed to develop into motor neurons in a test tube.

神经干细胞现在可以在试管慢慢的发育成为运动神经元。

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Three strands of DNA were synthesized so that when they were put into a test tube, they immediately became a molecular motor--a pair of DNA tweezers, held together at one end by a third piece of DNA that could be made to open and shut by adding or subtracting a fourth DNA strand.

FORBES: DNA May Make Computers, Not Run Them