\u1ede m\u1ed9t s\u1ed1 n\u01a1i c\u1ee7a n\u01b0\u1edbc Anh, ng\u01b0\u1eddi ta x\u00e2y d\u1ef1ng nh\u1eefng con \u0111\u01b0\u1eddng r\u1ea5t k\u1ef3 l\u1ea1. Nh\u1eefng con \u0111\u01b0\u1eddng n\u00e0y tuy c\u0169ng l\u00e0m b\u1eb1ng xi m\u0103ng, nh\u01b0ng c\u00f3 \u0111i\u1ec1u kh\u00e1c l\u00e0 ti\u1ebfng \u1ed3n s\u1ea3n sinh ra khi xe ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng th\u1ea5p h\u01a1n c\u00e1c \u0111\u01b0\u1eddng th\u00f4ng th\u01b0\u1eddng kh\u00e1c 2-3 dB (\u0111\u00eaxiben), v\u00ec v\u1eady \u0111\u01b0\u1ee3c g\u1ecdi m\u1ed9t c\u00e1ch \u0111\u1eb9p \u0111\u1ebd l\u00e0 “\u0111\u01b0\u1eddng ti\u00eau \u00e2m”.<\/p>\n\n\n\n
Vi\u1ec7c nghi\u00ean c\u1ee9u x\u00e2y d\u1ef1ng \u0111\u01b0\u1eddng ti\u00eau \u00e2m n\u1ea3y sinh t\u1eeb \u0111\u1eb7c t\u00ednh c\u1ee7a c\u00e1c t\u1ea5m x\u1ed1p c\u1ee7a bu\u1ed3ng c\u00e1ch \u00e2m. C\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u00e3 \u00e1p d\u1ee5ng nguy\u00ean l\u00fd c\u00e1c t\u1ea5m x\u1ed1p c\u00f3 th\u1ec3 kh\u1eed ti\u1ebfng \u1ed3n \u0111\u00e3 s\u00e1ng ch\u1ebf m\u1ed9t lo\u1ea1i b\u00ea t\u00f4ng nh\u1ef1a \u0111\u01b0\u1eddng x\u1ed1p \u0111\u1ec3 l\u00e0m \u0111\u01b0\u1eddng, gi\u1ea3m \u0111\u01b0\u1ee3c ti\u1ebfng \u1ed3n giao th\u00f4ng. B\u00ea t\u00f4ng nh\u1ef1a \u0111\u01b0\u1eddng x\u1ed1p c\u00f3 th\u1ec3 l\u1ee3i d\u1ee5ng l\u1ed7 r\u1ed7ng v\u00e0 t\u00ednh \u0111\u00e0n h\u1ed3i \u1edf b\u00ean trong v\u1eadt li\u1ec7u \u0111\u1ec3 h\u1ea5p th\u1ee5 s\u00f3ng \u1ee9ng l\u1ef1c \u0111\u00e0n h\u1ed3i s\u1ea3n sinh ra khi xe ch\u1ea1y, l\u00e0m ti\u00eau tan ph\u1ea7n l\u1edbn nhi\u1ec7t n\u0103ng b\u00ean trong v\u1eadt li\u1ec7u do ch\u1ea5n \u0111\u1ed9ng g\u00e2y ra, do \u0111\u00f3 l\u00e0m cho c\u1ea3 s\u1ef1 ch\u1ea5n \u0111\u1ed9ng v\u00e0 ti\u1ebfng \u1ed3n \u0111\u1ec1u b\u1ecb suy gi\u1ea3m nhanh ch\u00f3ng. Tuy nhi\u00ean, lo\u1ea1i \u0111\u01b0\u1eddng n\u00e0y sau khi b\u1ecb b\u0103ng tuy\u1ebft ph\u1ee7 l\u00ean th\u00ec to\u00e0n b\u1ed9 c\u00e1c l\u1ed7 r\u1ed7ng tr\u00ean m\u1eb7t \u0111\u01b0\u1eddng \u0111\u1ec1u b\u1ecb \u0111\u00f3ng b\u0103ng, \u0111\u01b0\u1eddng kh\u00f4ng s\u1eed d\u1ee5ng \u0111\u01b0\u1ee3c. V\u1eady th\u00ec c\u00f3 th\u1ec3 t\u00ecm \u0111\u01b0\u1ee3c m\u1ed9t v\u1eadt li\u1ec7u m\u1edbi l\u00e0m m\u1eb7t \u0111\u01b0\u1eddng m\u00e0 kh\u00f4ng b\u1ecb \u1ea3nh h\u01b0\u1edfng c\u1ee7a kh\u00ed h\u1eadu kh\u00f4ng?<\/p>\n\n\n\n
C\u00e1c nh\u00e0 khoa h\u1ecdc Anh \u0111\u00e3 s\u00e1ng ch\u1ebf m\u1ed9t lo\u1ea1i v\u1eadt li\u1ec7u m\u1edbi g\u1ecdi l\u00e0 xi m\u0103ng h\u1ea1t. Khi s\u1eed d\u1ee5ng lo\u1ea1i xi m\u0103ng h\u1ea1t n\u00e0y \u0111\u1ec3 r\u1ea3i l\u00ean m\u1eb7t \u0111\u01b0\u1eddng, tr\u01b0\u1edbc h\u1ebft c\u1ea7n \u0111\u1ed5 m\u1ed9t l\u1edbp b\u00ea t\u00f4ng c\u00f3 chi\u1ec1u d\u00e0y ch\u1eebng 20 cm, t\u1ea1o th\u00e0nh m\u1ed9t m\u1eb7t \u0111\u01b0\u1eddng b\u1eb1ng ph\u1eb3ng, sau \u0111\u00f3 r\u1ea3i m\u1ed9t l\u1edbp xi m\u0103ng h\u1ea1t d\u00e0y kho\u1ea3ng 2 cm, b\u00ean tr\u00ean l\u1ea1i phun m\u1ed9t ho\u00e1 ch\u1ea5t ng\u0103n ng\u1eeba v\u1eefa xi m\u0103ng \u0111\u00f4ng k\u1ebft tr\u00ean m\u1eb7t \u0111\u01b0\u1eddng. Sau 12 gi\u1edd d\u00f9ng m\u00e1y ch\u1ea3i s\u1ea1ch l\u1edbp v\u1eefa xi m\u0103ng \u0111i, do \u0111\u00f3 h\u00ecnh th\u00e0nh m\u1eb7t \u0111\u01b0\u1eddng c\u00f3 h\u1ea1t tr\u1ed3i l\u00ean. M\u1eb7t \u0111\u01b0\u1eddng l\u00e0m nh\u01b0 th\u1ebf n\u00e0y do b\u1ec1 m\u1eb7t c\u1ee7a n\u00f3 c\u00f3 s\u1ef1 m\u1ea5p m\u00f4 c\u1ef1c nh\u1ecf kh\u00f4ng theo m\u1ed9t quy t\u1eafc n\u00e0o, do \u0111\u00f3 c\u0169ng gi\u1ed1ng nh\u01b0 \u0111\u01b0\u1eddng b\u00ea t\u00f4ng nh\u1ef1a \u0111\u01b0\u1eddng x\u1ed1p, c\u0169ng c\u00f3 th\u1ec3 h\u1ea5p th\u1ee5 s\u00f3ng \u1ee9ng l\u1ef1c \u0111\u00e0n h\u1ed3i do ti\u1ebfng \u1ed3n giao th\u00f4ng g\u00e2y n\u00ean, \u0111\u1ea1t \u0111\u01b0\u1ee3c m\u1ee5c \u0111\u00edch kh\u1eed ti\u1ebfng \u1ed3n. \u01afu \u0111i\u1ec3m c\u1ee7a lo\u1ea1i “\u0111\u01b0\u1eddng ti\u00eau \u00e2m” n\u00e0y l\u00e0 d\u00f9 v\u1ec1 m\u00f9a h\u00e8 tr\u1eddi n\u1eafng chang chang hay m\u00f9a \u0111\u00f4ng b\u0103ng tuy\u1ebft c\u0169ng kh\u00f4ng \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn giao th\u00f4ng b\u00ecnh th\u01b0\u1eddng v\u00e0 ch\u1ee9c n\u0103ng “ti\u00eau \u00e2m” c\u1ee7a n\u00f3 do \u1ea3nh h\u01b0\u1edfng c\u1ee7a s\u1ef1 bi\u1ebfn \u0111\u1ed5i th\u1eddi ti\u1ebft.<\/p>\n\n\n\n
D\u00f9ng xi m\u0103ng h\u1ea1t \u0111\u1ec3 l\u00e0m \u0111\u01b0\u1eddng cao t\u1ed1c, kh\u00f4ng nh\u1eefng c\u00f3 th\u1ec3 “kh\u1eed h\u1ebft” ti\u1ebfng \u1ed3n giao th\u00f4ng tr\u00ean m\u1eb7t \u0111\u01b0\u1eddng, m\u00e0 c\u00f2n do c\u00e1c h\u1ea1t xi m\u0103ng tr\u1ed3i l\u00ean l\u00e0m cho s\u1ef1 ph\u1ea3n quang c\u1ee7a m\u1eb7t \u0111\u01b0\u1eddng gi\u1ea3m \u0111i, m\u00e0u s\u1eafc c\u1ee7a m\u1eb7t \u0111\u01b0\u1eddng t\u01b0\u01a1ng \u0111\u1ed1i h\u00e0i ho\u00e0 v\u1edbi m\u00f4i tr\u01b0\u1eddng \u0111i\u1ec1u \u0111\u00f3 s\u1ebd l\u00e0m cho n\u00f3 tr\u1edf th\u00e0nh m\u1ed9t th\u1ef1c t\u1ebf c\u00f3 \u00edch cho vi\u1ec7c ph\u00e1t tri\u1ec3n giao th\u00f4ng \u0111\u01b0\u1eddng b\u1ed9 trong t\u01b0\u01a1ng lai.<\/p>\n\n\n\n
T\u1eeb kh\u00f3a: \u0110\u01b0\u1eddng ti\u00eau \u00e2m; Ti\u1ebfng \u1ed3n giao th\u00f4ng.<\/p>\n","protected":false},"excerpt":{"rendered":"
\u1ede m\u1ed9t s\u1ed1 n\u01a1i c\u1ee7a n\u01b0\u1edbc Anh, ng\u01b0\u1eddi ta x\u00e2y d\u1ef1ng nh\u1eefng con \u0111\u01b0\u1eddng r\u1ea5t k\u1ef3 l\u1ea1. Nh\u1eefng con \u0111\u01b0\u1eddng n\u00e0y tuy c\u0169ng l\u00e0m b\u1eb1ng xi m\u0103ng, nh\u01b0ng c\u00f3 \u0111i\u1ec1u kh\u00e1c l\u00e0 ti\u1ebfng \u1ed3n s\u1ea3n sinh ra khi xe ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng th\u1ea5p h\u01a1n c\u00e1c \u0111\u01b0\u1eddng th\u00f4ng th\u01b0\u1eddng kh\u00e1c 2-3 dB (\u0111\u00eaxiben), v\u00ec v\u1eady \u0111\u01b0\u1ee3c […]<\/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":[15,16],"tags":[],"class_list":["post-8820","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-ky-thuat"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/8820","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=8820"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/8820\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=8820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=8820"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=8820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}