Crookes radiometers have been the subject of numerous theoretical, numerical, and experimental studies because of the complicated forces they exhibit as well as their potential applications to light sensing and actuation. The majority of these studies have focused on classical radiometers, which function under low vacuum pressures. In contrast, here we report a radiometer with microengineered vanes that rotates at atmospheric pressure. Its functionality at pressures thousands of times higher than previous light mills is due to unique attributes of the nanocardboard that forms its vanes: 1) the extremely low areal density (0.1 mg/cm 2 ) of nanocardboard reduces the vane masses by two orders of magnitude; 2) its lower thermal conductivity allows a greater cross-vane temperature difference; and 3) its microchannels dramatically increase the thermal transpiration flow that drives the rotation. Intriguingly, the experimentally observed rotation speeds are substantially higher than those theoretically expected. Our device demonstrates new possibilities for micromanipulation, propulsion of aerial vehicles, and light-powered generators. [2020-0165].

中文翻译：

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带纳米纸板叶片的大气压辐射计演示


克鲁克斯辐射计因其表现出的复杂力及其在光传感和驱动方面的潜在应用而成为众多理论、数值和实验研究的主题。这些研究大部分集中在经典辐射计上，它们在低真空压力下工作。相比之下，我们在这里报告了一种带有微工程叶片的辐射计，该叶片在大气压下旋转。其在比以前的轻磨机高数千倍的压力下发挥作用，是由于形成其叶片的纳米纸板的独特属性：1) 纳米纸板极低的面密度 (0.1 mg/cm 2 ) 将叶片质量减少了两个数量级; 2）其较低的导热系数允许较大的叶片交叉温差； 3）其微通道极大地增加了驱动旋转的热蒸腾流。有趣的是，实验观察到的旋转速度远高于理论上预期的速度。我们的设备展示了微操作、飞行器推进和光动力发电机的新可能性。 [2020-0165]。