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但当史蒂夫开口说话，我心中的犹豫瞬间消散。我从未见过如此充满激情与愿景的人。他谈论未来——科技将释放人类创造力与潜能，以连结与提升我们的方式，甚至超出他的想象。为此，他需要一群充满好奇心的人，为超越自身的目标而努力。我知道我必须加入。
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Optical-based smoke alarms use light instead. They are slightly better at detecting the large smoke particles created by slow, smouldering fires. When such particles enter a chamber in the device, they scatter light from a small light source, which is then picked up by a photoelectric sensor.
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