{"id":1427,"date":"2018-11-08T13:08:14","date_gmt":"2018-11-08T12:08:14","guid":{"rendered":"https:\/\/www.enviblog.cz\/blog\/?p=1427"},"modified":"2018-12-27T12:08:40","modified_gmt":"2018-12-27T11:08:40","slug":"ignis-brunensis-2018-pod-mikroskopem","status":"publish","type":"post","link":"https:\/\/www.enviblog.cz\/blog\/2018\/11\/08\/ignis-brunensis-2018-pod-mikroskopem\/","title":{"rendered":"M\u011b\u0159en\u00ed kvality ovzdu\u0161\u00ed b\u011bhem brn\u011bnsk\u00e9 p\u0159ehl\u00eddky oh\u0148ostroj\u016f Ignis Brunensis 2018 \u2013 4. d\u00edl – Ignis Brunensis 2018 pod mikroskopem"},"content":{"rendered":"

Oh\u0148ostroj je bezesporu div\u00e1cky atraktivn\u00ed pod\u00edvanou. Bezpe\u010dnou, pokud se dr\u017e\u00edte n\u00e1vodu k pou\u017eit\u00ed\u00a0 nebo alespo\u0148 stoj\u00edte v bezpe\u010dn\u00e9 vzd\u00e1lenosti :-). Jak ale funguje a jak\u00fdm chemick\u00fdm l\u00e1tk\u00e1m \u0161\u00ed\u0159\u00edc\u00edm se v kou\u0159ov\u00e9 vle\u010dce je div\u00e1k vystaven? Poj\u010fme se pod\u00edvat zbl\u00edzka.<\/em><\/strong><\/p>\n

1. \u00davod – popis m\u011b\u0159en\u00ed, lokality a meteorologick\u00fdch podm\u00ednek<\/a>
\n<\/strong>2. Kvalita ovzdu\u0161\u00ed – PM10<\/sub>, PM2,5<\/sub>, NO2<\/sub>, NO, NOx<\/sub>, SO2<\/sub> a CO<\/a>
\n3. Kvalita ovzdu\u0161\u00ed – kovy<\/a>
\n4. Kvalita ovzdu\u0161\u00ed – \u010d\u00e1sticov\u00e1 anal\u00fdza SEM\/EDX<\/strong><\/p>\n

Oh\u0148ostrojem podle vyhl\u00e1\u0161ky \u010d. 174\/1992 Sb. je sou\u010dasn\u00e9 nebo v kr\u00e1tk\u00e9m \u010dasov\u00e9m sledu n\u00e1sleduj\u00edc\u00ed odpalov\u00e1n\u00ed pyrotechnick\u00fdch p\u0159edm\u011bt\u016f t\u0159\u00eddy II a III s p\u0159\u00edpadn\u00fdm pou\u017eit\u00edm pyrotechnick\u00fdch p\u0159edm\u011bt\u016f t\u0159\u00eddy I.<\/p>\n

Pyrotechnick\u00e9 p\u0159edm\u011bty – v\u00fdrobky obsahuj\u00edc\u00ed technologicky zpracovan\u00e9 pyrotechnick\u00e9 slo\u017ee, p\u0159\u00edpadn\u011b i mal\u00e1 mno\u017estv\u00ed v\u00fdbu\u0161nin. Jsou nebezpe\u010dn\u00e9 p\u0159edev\u0161\u00edm po\u017e\u00e1rem a p\u0159i dodr\u017een\u00ed n\u00e1vodu k pou\u017e\u00edv\u00e1n\u00ed neohroz\u00ed v\u00fdbuchem bezpe\u010dnost osob a majetku.<\/p>\n

Pyrotechnick\u00e9 slo\u017ee jsou mechanick\u00e9 sm\u011bsi ho\u0159lavin, oxidovadel, pojiv a dal\u0161\u00edch p\u0159\u00eddavn\u00fdch l\u00e1tek, jejich\u017e chemickou p\u0159em\u011bnou (ve form\u011b r\u016fzn\u011b rychl\u00e9ho ho\u0159en\u00ed) se vyvol\u00e1vaj\u00ed sv\u011bteln\u00e9, tepeln\u00e9, zvukov\u00e9, d\u00fdmov\u00e9, tlakov\u00e9 a pohybov\u00e9 \u00fa\u010dinky (d\u00e1le jen „pyrotechnick\u00e9 efekty“).<\/p>\n

Jako okysli\u010dovadla<\/em><\/strong>, kter\u00e1 jsou rychle dostupn\u00fdm zdrojem kysl\u00edku pot\u0159ebn\u00e9ho k ho\u0159en\u00ed (ho\u0159en\u00ed pyrotechnick\u00fdch slo\u017e\u00ed tedy nen\u00ed z\u00e1visl\u00e9 na vzdu\u0161n\u00e9m kysl\u00edku), se pou\u017e\u00edvaj\u00ed nej\u010dast\u011bji dusi\u010dnany (KNO3<\/sub>, Ba(NO3<\/sub>),2<\/sub>, Sr(NO3<\/sub>)2<\/sub>), chlore\u010dnany (KClO3<\/sub>, Ba(ClO3<\/sub>)2<\/sub>) a chloristany (KClO4<\/sub>, Ba(ClO4<\/sub>)2<\/sub>, NH4<\/sub>ClO4<\/sub>).<\/p>\n

P\u0159\u00edklad rozkladu okysli\u010dovadla (dusi\u010dnanu):<\/p>\n

XNO3 <\/sub>(dusi\u010dnan) \u2192 XNO2<\/sub> (dusitan) + 1\/2O2 <\/sub>(kysl\u00edk)<\/p>\n

Sv\u011bteln\u00fd efekt oh\u0148ostroje je zalo\u017een na reakci ho\u0159laviny<\/em><\/strong> s kysl\u00edkem (ho\u0159en\u00ed) dodan\u00fdm okysli\u010dovadlem. Sou\u010dasn\u011b poskytuje tolik tepeln\u00e9 energie, aby sta\u010dila oh\u0159\u00e1t zbytek slo\u017ee na z\u00e1palnou teplotu. Mezi ho\u0159laviny pat\u0159\u00ed pr\u00e1\u0161kov\u00e9 kovy jako nap\u0159. hlin\u00edk (Al), ho\u0159\u010d\u00edk (Mg), titan (Ti), \u017eelezo (Fe), antimon (Sb) atd., d\u00e1le s\u00edra (S), fosfor (P), d\u0159ev\u011bn\u00e9 uhl\u00ed, \u0161kroby, cukry, nitrocelul\u00f3za atd.<\/p>\n

Jako pojiva<\/em><\/strong>, kter\u00e1 celou slo\u017e spoj\u00ed a dr\u017e\u00ed pohromad\u011b, slou\u017e\u00ed s\u00edra (S), arabsk\u00e1 guma, antracen, dextrin, \u0161krob atd.<\/p>\n

P\u0159\u00eddavn\u00e9 l\u00e1tky<\/em><\/strong> slou\u017e\u00ed k dosa\u017een\u00ed po\u017eadovan\u00fdch vlastnost\u00ed jednotliv\u00fdch slo\u017e\u00ed, m\u016f\u017eeme jimi ovlivnit nap\u0159. rychlost ho\u0159en\u00ed, barvu plamene, tvorbu d\u00fdmu, ale tak\u00e9 zlep\u0161it mechanickou a chemickou stabilitu pro bezpe\u010dn\u011bj\u0161\u00ed manipulaci. Hlavn\u00edm \u00fa\u010delem oh\u0148ostroj\u016f je sv\u011bteln\u00fd efekt, konkr\u00e9tn\u011b dosa\u017een\u00ed r\u016fzn\u00fdch barevn\u00fdch odst\u00edn\u016f plamene. L\u00e1tky barv\u00edc\u00ed plamen jsou po chemick\u00e9 str\u00e1nce p\u0159edev\u0161\u00edm soli alkalick\u00fdch kov\u016f a kov\u016f alkalick\u00fdch zemin, soli sod\u00edku (Na), drasl\u00edku (K), lithia (Li), stroncia (Sr), barya (Ba), ho\u0159\u010d\u00edk (Mg), soli v\u00e1pn\u00edku (Ca), d\u00e1le soli m\u011bdi (Cu), titan (Ti), pro zv\u00fd\u0161en\u00ed intenzity plamene se pou\u017e\u00edvaj\u00ed hlin\u00edk (Al), zinek (Zn) \u010di berilium (Be).<\/p>\n

Jako hnac\u00ed \u201cmotor\u201d<\/strong><\/em>, kter\u00fd vynese oh\u0148ostrojov\u00e9 t\u011bleso vysoko do vzduchu, se obvykle pou\u017e\u00edv\u00e1 sm\u011bs dusi\u010dnanu draseln\u00e9ho (KNO3<\/sub>), s\u00edry (S) a d\u0159ev\u011bn\u00e9ho uhl\u00ed (C) tzv. \u010dern\u00fd prach (black powder, gun powder), chemick\u00e1 reakce spojen\u00e1 s odp\u00e1len\u00edm oh\u0148ostroje potom m\u016f\u017ee vypadat takto:<\/p>\n

4KNO3<\/sub> (dusi\u010dnan draseln\u00fd) + S (s\u00edra) + 7C (uhl\u00edk v d\u0159ev\u011bn\u00e9m uhl\u00ed) \u2192 K2<\/sub>S (sulfid draseln\u00fd) + K2<\/sub>CO3<\/sub> (uhli\u010ditan draseln\u00fd) + 2N2<\/sub> (dus\u00edk gas) + 3CO2<\/sub> (oxid uhli\u010dit\u00fd)<\/p>\n

\"\"<\/p>\n

Obr. Oh\u0148ostrojov\u00e9 slo\u017ee<\/em><\/p>\n

Pro \u010d\u00e1sticovou anal\u00fdzu (p\u0159eva\u017eovaly \u010d\u00e1stice aerodynamick\u00e9ho pr\u016fm\u011bru do 10 \u00b5m tzv. PM10<\/sub>) pomoc\u00ed elektronov\u00e9ho mikroskopu byly odebr\u00e1ny 4 vzorky. Odb\u011br ka\u017ed\u00e9ho ze 4 vzork\u016f trval p\u0159esn\u011b 4 h, vzorkovalo se od 22 \u2013 02 h (odpalov\u00e1n\u00ed oh\u0148ostroj\u016f zapo\u010dalo ve 22,30\u00a0h a trvalo p\u0159ibli\u017en\u011b 20 min). Jeden \u00a0odb\u011br byl proveden ve stejnou denn\u00ed dobu, ale v\u00a0den bez oh\u0148ostroje a slou\u017eil jako referen\u010dn\u00ed vzorek.<\/p>\n

\"\"<\/a><\/p>\n

Obr. N\u00edzkoobjemov\u00fd vzorkova\u010d (vlevo) a jeho um\u00edst\u011bn\u00ed na brn\u011bnsk\u00e9 p\u0159ehrad\u011b (vpravo)<\/em><\/p>\n

Na brn\u011bnsk\u00e9 p\u0159ehrad\u011b p\u0159evl\u00e1d\u00e1 z\u00e1padn\u00ed a severoz\u00e1padn\u00ed proud\u011bn\u00ed vzduchu, vzorkova\u010d byl tedy um\u00edst\u011bn jihov\u00fdchodn\u011b od odpalovac\u00ed rampy, kter\u00e1 byla na vodn\u00ed hladin\u011b. Vzorkova\u010d tak zachytil kou\u0159ovou vle\u010dku.<\/p>\n

\"\"<\/a><\/p>\n

Obr. V\u011btrn\u00e1 r\u016f\u017eice z dat nam\u011b\u0159en\u00fdch v obdob\u00ed 2. 6. \u2013 14. 6. 18<\/em><\/p>\n

\"\"<\/a><\/p>\n

Obr. Polykarbon\u00e1tov\u00fd filtr s p\u00f3ry o velikosti 0,8 \u00b5m (\u010dern\u00e9 d\u00edry) a zachycen\u00fdmi prachov\u00fdmi \u010d\u00e1sticemi PM10<\/sub> (oh\u0148ostroj 6. 6. 18)<\/em><\/p>\n

\"\"<\/a><\/p>\n

Obr. Ob\u0159\u00ed a p\u0159esto pouh\u00fdm okem neviditeln\u00e1 pylov\u00e1 zrna. Polykarbon\u00e1tov\u00fd filtr s p\u00f3ry o velikosti 0,8 \u00b5m (\u010dern\u00e9 d\u00edry) a zachycen\u00fdmi prachov\u00fdmi \u010d\u00e1sticemi PM10<\/sub> (oh\u0148ostroj 6. 6. 18)
\n<\/em><\/p>\n

Elektronov\u00e1 mikroskopie vyu\u017e\u00edv\u00e1 interakce tzv. prim\u00e1rn\u00edch elektron\u016f s atomy vzorku v jeho povrchov\u00e9 vrstv\u011b, jedn\u00edm z v\u00fdsledk\u016f t\u00e9to interakce je emise foton\u016f RTG z\u00e1\u0159en\u00ed. Energie foton\u016f RTG z\u00e1\u0159en\u00ed je charakteristick\u00e1 pro dan\u00fd prvek a tak n\u00e1m detekce t\u011bchto foton\u016f poskytne informaci o prvkov\u00e9m slo\u017een\u00ed vzorku v m\u00edst\u011b anal\u00fdzy. Sou\u010dasn\u011b je mo\u017en\u00e9 na z\u00e1klad\u011b srovn\u00e1n\u00ed intenzit spektr\u00e1ln\u00edch \u010dar v rentgenov\u00e9 oblasti s intenzitami stejn\u00fdch \u010dar v p\u0159\u00edslu\u0161n\u00fdch standardech z\u00edskat kvantitativn\u00ed informaci ve form\u011b hmotnostn\u00edch procent jednotliv\u00fdch prvk\u016f (v na\u0161em konkr\u00e9tn\u00edm p\u0159\u00edpad\u011b pou\u017e\u00edv\u00e1me bezstandardovou metodu se ZAF korekc\u00ed a normalizac\u00ed, \u00a0v\u00fdsledek je pouze semikvantitativn\u00ed). Software pro automatickou anal\u00fdzu \u010d\u00e1stic n\u00e1m otev\u0159el cestu k anal\u00fdze n\u011bkolika tis\u00edc \u010d\u00e1stic na dan\u00e9m vzorku za \u010das, kter\u00e9mu nem\u016f\u017ee manu\u00e1ln\u00ed anal\u00fdza konkurovat. V\u00fdstupem \u010d\u00e1sticov\u00e9 anal\u00fdzy jsou kvalitativn\u00ed (z \u010deho \u010d\u00e1stice je), semikvantitativn\u00ed (kolik toho v n\u00ed p\u0159ibli\u017en\u011b je [hm. %] a morfologick\u00e1 informace (velikost a tvar \u201c2D\u201d \u010d\u00e1stice) o v\u0161ech analyzovan\u00fdch \u010d\u00e1stic\u00edch.<\/p>\n

Za \u00fa\u010delem rozt\u0159\u00edd\u011bn\u00ed \u010d\u00e1stic do t\u0159\u00edd byla vytvo\u0159ena klasifika\u010dn\u00ed krit\u00e9ria, d\u00edky kter\u00fdm bylo mo\u017en\u00e9 \u010d\u00e1stice na z\u00e1klad\u011b obsahu konkr\u00e9tn\u00edch prvk\u016f, pop\u0159\u00edpad\u011b ve spojen\u00ed s\u00a0jejich tvarem za\u0159adit. Pokud konkr\u00e9tn\u00ed \u010d\u00e1stice nesplnila krit\u00e9ria ani jedn\u00e9 ze t\u0159\u00edd klasifika\u010dn\u00edho sch\u00e9matu, byla za\u0159azena do t\u0159\u00eddy \u201eNeza\u0159azen\u00e1\u201d. V\u00a0p\u0159\u00edpad\u011b, \u017ee \u010d\u00e1stice splnila klasifika\u010dn\u00ed krit\u00e9ria v\u00edce ne\u017e jedn\u00e9 t\u0159\u00eddy, byla p\u0159i\u0159azena do v\u00edce t\u0159\u00edd. Z\u00a0toho tak\u00e9 plyne, \u017ee sou\u010det procentu\u00e1ln\u00edho zastoupen\u00ed jednotliv\u00fdch t\u0159\u00edd z\u00a0celku je v\u00a0sou\u010dtu vy\u0161\u0161\u00ed ne\u017e 100 %. Do t\u0159\u00eddy \u201cOh\u0148ostroje\u201d byla za\u0159azena \u010d\u00e1stice v p\u0159\u00edpad\u011b, \u017ee splnila jednu z podm\u00ednek:<\/p>\n