Po stalet\u00ed se lidstvo zab\u00fdvalo zd\u00e1nliv\u011b jednoduchou ot\u00e1zkou: pro\u010d je led tak kluzk\u00fd? Od olympijsk\u00fdch sportovc\u016f klouzaj\u00edc\u00edch po zmrzl\u00fdch trat\u00edch a\u017e po ka\u017edodenn\u00ed p\u00e1dy na chodn\u00edc\u00edch je tento fenom\u00e9n univerz\u00e1ln\u00ed, ale v\u011bdecky z\u00e1hadn\u00fd. Navzdory dlouhotrvaj\u00edc\u00edm spekulac\u00edm z\u016fst\u00e1vala definitivn\u00ed odpov\u011b\u010f v nedohlednu \u2013 a\u017e doned\u00e1vna. <\/p>\n
V\u011bdci tradi\u010dn\u011b nab\u00edzej\u00ed t\u0159i hlavn\u00ed vysv\u011btlen\u00ed. Prvn\u00ed, poch\u00e1zej\u00edc\u00ed z 19. stolet\u00ed, nazna\u010duje, \u017ee tlak p\u0159edm\u011btu (nap\u0159\u00edklad brusle) roztav\u00ed led a vytvo\u0159\u00ed mazac\u00ed vrstvu vody. Tato teorie je v\u0161ak neudr\u017eiteln\u00e1: lid\u00e9 nev\u00e1\u017e\u00ed dostate\u010dn\u011b, aby vytvo\u0159ili dostate\u010dn\u00fd tlak pro v\u00fdznamn\u00e9 t\u00e1n\u00ed. Druh\u00e1 hypot\u00e9za poukazuje na t\u0159en\u00ed: t\u0159en\u00ed mezi povrchem a ledem vytv\u00e1\u0159\u00ed teplo, co\u017e zp\u016fsobuje m\u00edstn\u00ed t\u00e1n\u00ed. I kdy\u017e to vysv\u011btluje klouz\u00e1n\u00ed po<\/em> zah\u00e1jen\u00ed pohybu, nevysv\u011btluje to po\u010d\u00e1te\u010dn\u00ed snadnost klouz\u00e1n\u00ed. T\u0159et\u00ed teorie p\u0159edpokl\u00e1d\u00e1 p\u0159edem roztavenou vrstvu vody na povrchu ledu kv\u016fli struktur\u00e1ln\u00edm rozd\u00edl\u016fm mezi pevnou a kapalnou vodou. Ale ani toto vysv\u011btlen\u00ed nedok\u00e1\u017ee pln\u011b vysv\u011btlit extr\u00e9mn\u00ed kluzkost. <\/p>\n Snaha porozum\u011bt kluzkosti ledu nen\u00ed jen akademick\u00e1 z\u00e1le\u017eitost. Nizozem\u0161t\u00ed v\u011bdci, poh\u00e1n\u011bn\u00ed touhou udr\u017eet si vedouc\u00ed postaven\u00ed sv\u00e9 zem\u011b v rychlobruslen\u00ed, vid\u00ed praktick\u00e9 aplikace. Krom\u011b sportu by komplexn\u00ed pochopen\u00ed t\u0159en\u00ed ledem mohlo m\u00edt glob\u00e1ln\u00ed d\u016fsledky. T\u0159en\u00ed p\u0159edstavuje asi 25 % celosv\u011btov\u00e9 spot\u0159eby energie, co\u017e znamen\u00e1, \u017ee odhalen\u00ed tajemstv\u00ed n\u00edzk\u00e9ho t\u0159en\u00ed ledu by mohlo v\u00e9st k v\u00fdznamn\u00fdm \u00faspor\u00e1m energie v r\u016fzn\u00fdch pr\u016fmyslov\u00fdch odv\u011btv\u00edch. <\/p>\n Ned\u00e1vn\u00fd v\u00fdzkum nazna\u010duje, \u017ee odpov\u011b\u010f m\u016f\u017ee spo\u010d\u00edvat ve struktu\u0159e samotn\u00e9 ledov\u00e9 plochy. M\u00edsto toho, aby se spol\u00e9hali pouze na t\u00e1n\u00ed, v\u011bdci nyn\u00ed teoretizuj\u00ed, \u017ee akce, \u0159ekn\u011bme, \u0161l\u00e1pnut\u00ed na led ni\u010d\u00ed jeho krystalickou strukturu a vytv\u00e1\u0159\u00ed \u201eamorfn\u00ed vrstvu\u201c \u2013 neuspo\u0159\u00e1dan\u00fd stav mezi pevnou l\u00e1tkou a kapalinou. Tato vrstva nen\u00ed \u00fapln\u011b rozpu\u0161t\u011bn\u00fd led, ale chaotick\u00e9 uspo\u0159\u00e1d\u00e1n\u00ed molekul, kter\u00e9 klade minim\u00e1ln\u00ed odpor pohybu. <\/p>\n Tato teorie, publikovan\u00e1 v \u010dasopise Physical Review Letters<\/em>, nazna\u010duje, \u017ee i p\u0159i extr\u00e9mn\u011b n\u00edzk\u00fdch teplot\u00e1ch se mohou zarovnan\u00e9 ledov\u00e9 krystaly pod tlakem rychle rozpadnout a zp\u016fsobit kluzkost. Rozbit\u00ed krystalick\u00e9 struktury usnad\u0148uje molekul\u00e1rn\u00ed pohyb a sni\u017euje t\u0159en\u00ed. <\/p>\n O kluzkosti ledu v\u011bdci diskutovali v\u00edce ne\u017e stolet\u00ed. Ned\u00e1vn\u00fd v\u00fdzkum ukazuje, \u017ee pravda nespo\u010d\u00edv\u00e1 v jedin\u00e9m vysv\u011btlen\u00ed, ale v kombinaci faktor\u016f. Roli hraje tlak, t\u0159en\u00ed a struktur\u00e1ln\u00ed poruchy. Tento objev by mohl otev\u0159\u00edt inovace ve sni\u017eov\u00e1n\u00ed t\u0159en\u00ed v pr\u016fmyslov\u00fdch odv\u011btv\u00edch od dopravy po v\u00fdrobu. Z\u00e1hada ledu m\u016f\u017ee b\u00fdt kone\u010dn\u011b vy\u0159e\u0161ena a slibuje skute\u010dn\u00e9 v\u00fdhody daleko za kluzi\u0161t\u011bm.<\/p>\n","protected":false},"excerpt":{"rendered":" Po stalet\u00ed se lidstvo zab\u00fdvalo zd\u00e1nliv\u011b jednoduchou ot\u00e1zkou: pro\u010d je led tak kluzk\u00fd? Od olympijsk\u00fdch sportovc\u016f klouzaj\u00edc\u00edch po zmrzl\u00fdch trat\u00edch a\u017e po ka\u017edodenn\u00ed p\u00e1dy na chodn\u00edc\u00edch je tento fenom\u00e9n univerz\u00e1ln\u00ed, ale v\u011bdecky z\u00e1hadn\u00fd. Navzdory dlouhotrvaj\u00edc\u00edm spekulac\u00edm z\u016fst\u00e1vala definitivn\u00ed odpov\u011b\u010f v nedohlednu \u2013 a\u017e doned\u00e1vna. Zaveden\u00e9 teorie V\u011bdci tradi\u010dn\u011b nab\u00edzej\u00ed t\u0159i hlavn\u00ed vysv\u011btlen\u00ed. Prvn\u00ed, poch\u00e1zej\u00edc\u00ed z […]<\/p>\n","protected":false},"author":1,"featured_media":7429,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"tdm_status":"","tdm_grid_status":""},"categories":[1],"tags":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/posts\/7430"}],"collection":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/comments?post=7430"}],"version-history":[{"count":0,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/posts\/7430\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/media\/7429"}],"wp:attachment":[{"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/media?parent=7430"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/categories?post=7430"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.schooler.org.ua\/cs\/wp-json\/wp\/v2\/tags?post=7430"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Role spot\u0159eby energie a n\u00e1rodn\u00ed hrdosti<\/h3>\n
Nov\u00fd vzhled: Amorfn\u00ed vrstvy a molekul\u00e1rn\u00ed poruchy<\/h3>\n
Pro\u010d je to d\u016fle\u017eit\u00e9<\/h3>\n