自由基是什么？它是如何产生的？What are free radicals? How did it come about?

array(7) { [0]=> object(stdClass)#2280 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "sZWiQO31oJ8" ["related_video_title"]=> string(89) "「老闆給我工作，我就該鞠躬盡瘁？」Z世代不這麼想 #生活講堂 EP15" ["posted_time"]=> string(21) "1 день назад" ["channelName"]=> string(12) "生活講堂" } [1]=> object(stdClass)#2253 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "O7r1-xFZAVM" ["related_video_title"]=> string(51) "СТРЕСС СЖИГАЕТ ТЕБЯ ИЗНУТРИ" ["posted_time"]=> string(24) "49 минут назад" ["channelName"]=> string(10) "Айсер" } [2]=> object(stdClass)#2278 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "dUGhc6OEAiQ" ["related_video_title"]=> string(55) "6/12葉子老師猿猴式超慢跑還您健康不是夢" ["posted_time"]=> string(19) "1 час назад" ["channelName"]=> string(24) "葉子老師健康講座" } [3]=> object(stdClass)#2285 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "FdTWIbtvo7E" ["related_video_title"]=> string(100) "Botella de agua de hidrógeno, el mejor generador de botellas de agua de hidrógeno 2024" ["posted_time"]=> string(27) "9 месяцев назад" ["channelName"]=> string(17) "Unosuich Hydrogen" } [4]=> object(stdClass)#2264 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "_sDU9tYUdig" ["related_video_title"]=> string(98) "Pem Hydrogen Electrolyzer SPE Electrolysis Pure Water Electrolyser Hydrogen Electrolytic Fuel Cell" ["posted_time"]=> string(25) "4 месяца назад" ["channelName"]=> string(17) "Unosuich Hydrogen" } [5]=> object(stdClass)#2282 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "-71dL3J8ZdI" ["related_video_title"]=> string(135) "Bouteille d'eau à hydrogène, meilleur générateur de bouteille d'eau à hydrogène 2024, gaz H2" ["posted_time"]=> string(27) "8 месяцев назад" ["channelName"]=> string(17) "Unosuich Hydrogen" } [6]=> object(stdClass)#2277 (5) { ["video_id"]=> int(9999999) ["related_video_id"]=> string(11) "NlEHjfDIXwU" ["related_video_title"]=> string(95) "Hydrogen Water Bath Bombs Hydrogen Gas Generator H2 Gas Water Shower Salt BubbleBath 100~500PPB" ["posted_time"]=> string(25) "4 месяца назад" ["channelName"]=> string(17) "Unosuich Hydrogen" } }