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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.
,更多细节参见搜狗输入法2026
2月13日,北京人民大会堂。作为获得2025年度中国政府友谊奖的外国专家代表,德国海瑞恩集团董事长尤根·海瑞恩受邀出席一场新春座谈会。
Москвичей предупредили о резком похолодании09:45