V\u00e0o n\u0103m 1943, \u1edf th\u00e0nh ph\u1ed1 Los Angeles c\u1ee7a n\u01b0\u1edbc M\u1ef9 b\u1ed7ng nhi\u00ean c\u00f3 \u0111\u00e1m kh\u00f3i m\u00f9 m\u00e0u xanh nh\u1ea1t bay ch\u1ea7m ch\u1eadm tr\u00ean b\u1ea7u tr\u1eddi. Kh\u00f4ng \u00edt c\u01b0 d\u00e2n trong th\u00e0nh ph\u1ed1 c\u1ea3m th\u1ea5y kh\u00f3 th\u1edf, m\u1eaft b\u1ecb \u0111\u1ecf, s\u1ed1 ng\u01b0\u1eddi b\u1ecb vi\u00eam m\u0169i, vi\u00eam h\u1ecdng gia t\u0103ng. Th\u00e1ng 11 – 1952, \u1edf th\u00e0nh ph\u1ed1 Califonia l\u1ea1i x\u1ea3y ra s\u1ef1 ki\u1ec7n t\u01b0\u01a1ng t\u1ef1, g\u00e2y t\u1eed vong cho h\u01a1n 400 c\u1ee5 gi\u00e0 tr\u00ean 65 tu\u1ed5i. V\u1eady trong kh\u00f4ng kh\u00ed \u0111\u00e3 x\u1ea3y ra s\u1ef1 ki\u1ec7n g\u00ec v\u1eady? B\u00ed m\u1eadt c\u1ee7a “kh\u00ed \u0111\u1ed9c” n\u00e0y l\u00e0 g\u00ec?<\/p>\n\n\n\n
Nguy\u00ean do l\u00e0 ch\u1ea5t kh\u00ed lo\u1ea1i oxit nit\u01a1 c\u00f9ng nh\u1eefng ch\u1ea5t kh\u00ed c\u00f3 h\u1ea1i kh\u00e1c khi \u0111\u1ea1t \u0111\u1ebfn n\u1ed3ng \u0111\u1ed9 n\u00e0o \u0111\u00f3, d\u01b0\u1edbi t\u00e1c d\u1ee5ng c\u1ee7a \u00e1nh s\u00e1ng M\u1eb7t Tr\u1eddi \u0111\u00e3 g\u00e2y ra m\u1ed9t s\u1ed1 ph\u1ea3n \u1ee9ng ho\u00e1 h\u1ecdc ph\u1ee9c t\u1ea1p, t\u1ea1o n\u00ean h\u1ec7 th\u1ed1ng c\u00e1c ch\u1ea5t kh\u00ed \u0111\u1ed9c h\u1ea1i xanh nh\u1ea1t. \u0110\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng \u0111\u01b0\u1eddng h\u00f4 h\u1ea5p c\u1ee7a ng\u01b0\u1eddi nh\u01b0 l\u1ed7 m\u0169i, cu\u1ed1ng h\u1ecdng, cu\u1ed1ng ph\u1ed5i v\u00e0 ph\u1ed5i, c\u00e1c ch\u1ea5t kh\u00ed \u0111\u1ed9c s\u1ebd g\u00e2y t\u00e1c d\u1ee5ng k\u00edch th\u00edch r\u1ea5t m\u1ea1nh g\u00e2y n\u00ean b\u1ec7nh cho \u0111\u01b0\u1eddng h\u00f4 h\u1ea5p. Nhi\u1ec1u th\u00e0nh ph\u1ed1 l\u1edbn \u1edf c\u00e1c n\u01b0\u1edbc kh\u00e1c tr\u00ean th\u1ebf gi\u1edbi nh\u01b0 Cana\u0111a, Nh\u1eadt B\u1ea3n, \u00dac, H\u00e0 Lan\u2026 \u0111\u1ec1u \u0111\u00e3 x\u1ea3y ra c\u00e1c hi\u1ec7n t\u01b0\u1ee3ng t\u01b0\u01a1ng t\u1ef1. \u1ede nh\u00e0 m\u00e1y ho\u00e1 d\u1ea7u T\u00e2y C\u1ed1 thu\u1ed9c th\u00e0nh ph\u1ed1 Lan Ch\u00e2u, Trung Qu\u1ed1c c\u0169ng \u0111\u00e3 x\u1ea3y ra s\u1ef1 c\u1ed1 “m\u00e2y m\u00f9 \u0111\u1ed9c” v\u00e0o n\u0103m 1974.<\/p>\n\n\n\n
V\u00ec sao hi\u1ec7n t\u01b0\u1ee3ng m\u00e2y m\u00f9 \u0111\u1ed9c l\u1ea1i xu\u1ea5t hi\u1ec7n \u1edf nh\u1eefng th\u00e0nh ph\u1ed1 c\u00f4ng nghi\u1ec7p ph\u00e1t tri\u1ec3n? C\u00e1c nh\u00e0 khoa h\u1ecdc g\u1ecdi hi\u1ec7n t\u01b0\u1ee3ng m\u00e2y m\u00f9 \u0111\u1ed9c l\u00e0 m\u00e2y m\u00f9 quang ho\u00e1. Ch\u00fang ta \u0111\u1ec1u bi\u1ebft r\u1eb1ng \u1edf c\u00e1c th\u00e0nh ph\u1ed1 c\u00f4ng nghi\u1ec7p l\u1edbn, t\u1eadp trung m\u1ed9t l\u01b0\u1ee3ng l\u1edbn kh\u00ed th\u1ea3i c\u1ee7a \u00f4 t\u00f4 v\u00e0 c\u00e1c nh\u00e0 m\u00e1y c\u00f4ng nghi\u1ec7p.<\/p>\n\n\n\n
\u0110\u00f3 ch\u00ednh l\u00e0 c\u01a1 s\u1edf cho vi\u1ec7c sinh ra \u00f4 nhi\u1ec5m quang ho\u00e1. Lo\u1ea1i kh\u00ed th\u1ea3i n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 t\u1ea1p ch\u1ea5t \u00f4 nhi\u1ec5m s\u01a1 c\u1ea5p, trong \u0111\u00f3 ch\u1ee7 y\u1ebfu l\u00e0 c\u00e1c nit\u01a1 oxit v\u00e0 cacbon oxit. D\u01b0\u1edbi t\u00e1c d\u1ee5ng c\u1ee7a b\u1ee9c x\u1ea1 M\u1eb7t Tr\u1eddi (ch\u1ee7 y\u1ebfu l\u00e0 c\u00e1c tia t\u1eed ngo\u1ea1i c\u00f3 b\u01b0\u1edbc s\u00f3ng l\u1edbn h\u01a1n 350nm), c\u00e1c ch\u1ea5t \u00f4 nhi\u1ec5m s\u01a1 c\u1ea5p s\u1ebd ph\u00e1t sinh c\u00e1c ph\u1ea3n \u1ee9ng quang ho\u00e1 t\u1ea1o th\u00e0nh c\u00e1c ch\u1ea5t \u00f4 nhi\u1ec5m th\u1ee9 c\u1ea5p l\u00e0 ozon, metan\u2026<\/p>\n\n\n\n
Khi c\u00e1c ch\u1ea5t \u00f4 nhi\u1ec5m th\u1ee9 c\u1ea5p \u0111\u1ea1t \u0111\u1ebfn n\u1ed3ng \u0111\u1ed9 nh\u1ea5t \u0111\u1ecbnh n\u00e0o \u0111\u00f3 trong kh\u00f4ng kh\u00ed s\u1ebd t\u1ea1o th\u00e0nh c\u00e1c ch\u1ea5t \u00f4 nhi\u1ec5m \u1edf tr\u1ea1ng th\u00e1i m\u00e2y m\u00f9.<\/p>\n\n\n\n
S\u1ef1 \u00f4 nhi\u1ec5m quang ho\u00e1 kh\u00f4ng ch\u1ec9 g\u00e2y t\u00e1c h\u1ea1i cho s\u1ee9c kho\u1ebb con ng\u01b0\u1eddi m\u00e0 c\u00f2n g\u00e2y t\u00e1c h\u1ea1i l\u1edbn cho th\u1ef1c v\u1eadt, th\u1eadm ch\u00ed l\u00e0m cao su b\u1ecb l\u00e3o ho\u00e1, l\u00e0m nh\u1ea1t m\u00e0u c\u1ee7a ch\u1ea5t m\u00e0u\u2026<\/p>\n\n\n\n
M\u00e2y m\u00f9 quang ho\u00e1 c\u00f3 li\u00ean quan \u0111\u1ebfn ho\u00e0n c\u1ea3nh \u0111\u1ecba l\u00fd c\u1ee7a c\u00e1c th\u00e0nh ph\u1ed1, \u0111i\u1ec1u ki\u1ec7n nhi\u1ec7t \u0111\u1ed9, v\u1eadn t\u1ed1c gi\u00f3\u2026 V\u00ed d\u1ee5 \u1edf c\u00e1c th\u00e0nh ph\u1ed1 Los Angeles, Califonia (M\u1ef9), nhi\u1ec1u l\u1ea7n x\u1ea3y ra hi\u1ec7n t\u01b0\u1ee3ng m\u00e2y m\u00f9 quang ho\u00e1 li\u00ean quan ch\u1eb7t ch\u1ebd \u0111\u1ebfn \u0111i\u1ec1u ki\u1ec7n \u0111\u1ecba l\u00fd c\u00f3 ba m\u1eb7t n\u00fai bao quanh \u1edf hai th\u00e0nh ph\u1ed1.<\/p>\n\n\n\n
Nh\u01b0ng n\u00f3i chung, \u0111\u1ee9ng \u0111\u1ea7u “c\u00e1c t\u1ed9i danh” g\u00e2y \u00f4 nhi\u1ec5m quang ho\u00e1 l\u00e0 kh\u00ed th\u1ea3i do \u00f4 t\u00f4 v\u00e0 c\u00e1c nh\u00e0 m\u00e1y c\u00f4ng nghi\u1ec7p th\u1ea3i ra.<\/p>\n\n\n\n
Ch\u1ec9 c\u00f3 c\u00e1ch c\u1ea3i ti\u1ebfn k\u1ef9 thu\u1eadt gi\u1ea3m \u0111\u01b0\u1ee3c ngu\u1ed3n kh\u00ed th\u1ea3i m\u1edbi c\u1ea3i thi\u1ec7n \u0111\u01b0\u1ee3c nguy\u00ean nh\u00e2n ch\u1ee7 y\u1ebfu g\u00e2y \u00f4 nhi\u1ec5m quang ho\u00e1.<\/p>\n\n\n\n
T\u1eeb kho\u00e1: \u00d4 nhi\u1ec5m quang ho\u00e1; Ch\u1ea5t g\u00e2y \u00f4 nhi\u1ec5m th\u1ee9 c\u1ea5p.<\/p>\n\n\n\n
<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"
V\u00e0o n\u0103m 1943, \u1edf th\u00e0nh ph\u1ed1 Los Angeles c\u1ee7a n\u01b0\u1edbc M\u1ef9 b\u1ed7ng nhi\u00ean c\u00f3 \u0111\u00e1m kh\u00f3i m\u00f9 m\u00e0u xanh nh\u1ea1t bay ch\u1ea7m ch\u1eadm tr\u00ean b\u1ea7u tr\u1eddi. Kh\u00f4ng \u00edt c\u01b0 d\u00e2n trong th\u00e0nh ph\u1ed1 c\u1ea3m th\u1ea5y kh\u00f3 th\u1edf, m\u1eaft b\u1ecb \u0111\u1ecf, s\u1ed1 ng\u01b0\u1eddi b\u1ecb vi\u00eam m\u0169i, vi\u00eam h\u1ecdng gia t\u0103ng. Th\u00e1ng 11 – 1952, \u1edf th\u00e0nh […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[8,15],"tags":[],"class_list":["post-7958","post","type-post","status-publish","format-standard","hentry","category-hoa-hoc","category-hoi-dap-khoa-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7958","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=7958"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/7958\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=7958"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=7958"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=7958"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}