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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，这一点在体育直播中也有详细论述
"I don't think CNN would become Fox News overnight," says Seth Stern, chief advocate at the Freedom of the Press Foundation, noting that there are already several popular news outlets serving right-wing audiences. "But coverage could be softened, critiques of the Trump administration could be reduced, hosts that are known for being particularly critical... could be fired."，这一点在Line官方版本下载中也有详细论述
Weak shock waves triggered by micro-cracks in the adhesive layer of tape cause it to screech when being unspooled from its roll.