Liesegang rings? fascinating creations ntawm ntuj
"Lub voj voog ntawm Dab Ntxwg Nyoog"
Thov saib ob peb daim duab qhia txog cov kab mob nyob thiab cov qauv ntawm cov tsiaj tsis muaj sia: cov kab mob ntawm cov kab mob hauv nruab nrab agar, pwm loj hlob ntawm cov txiv hmab txiv ntoo, fungi ntawm lub nroog nyom thiab cov zaub mov - agate, malachite, sandstone. Dab tsi yog txhua yam khoom muaj sib xws? Qhov no yog lawv cov qauv, muaj xws li (ntau dua los yog tsawg dua kom meej meej) concentric voj voog. Chemists yuav hu lawv Liesegang rings.
Lub npe ntawm cov qauv no los ntawm lub npe ntawm tus neeg nrhiav pom? Raphael Eduard Liesegang, txawm hais tias nws tsis yog thawj tus los piav txog lawv. Qhov no tau ua tiav xyoo 1855 los ntawm Friedlieb Ferdinand Runge, uas tau koom nrog, tshwj xeeb, hauv kev ua cov tshuaj tiv thaiv ntawm cov ntawv lim. Tsim los ntawm German chemist? () tuaj yeem suav hais tias yog thawj lub nplhaib Liesegang tau txais, thiab cov txheej txheem ntawm lawv cov kev npaj yog daim ntawv chromatography. Txawm li cas los xij, qhov kev tshawb pom tsis tau pom hauv ntiaj teb kev tshawb fawb? Runge tau ua qhov no ib nrab xyoo ua ntej ntawm lub sijhawm (Lavxias teb sab botanist Mikhail Semyonovich Tsvet, uas ua haujlwm hauv Warsaw thaum pib ntawm lub xyoo pua XNUMXth, yog ib tug paub zoo inventor ntawm chromatography). Zoo, qhov no tsis yog thawj qhov xwm txheej hauv keeb kwm ntawm kev tshawb fawb; Tom qab tag nrho, txawm tias kev tshawb pom yuav tsum "tuaj raws sijhawm."
Raphael Eduard Liesegang (1869-1947)? German chemist thiab ua lag luam hauv kev lag luam yees duab. Raws li ib tug kws tshawb fawb, nws kawm txog chemistry ntawm colloids thiab cov khoom siv yees duab. Nws nto moo rau kev tshawb nrhiav cov qauv hu ua Liesegang rings.
Lub koob meej ntawm tus discoverer tau txais los ntawm R. E. Liesegang, uas tau pab los ntawm kev sib koom ua ke ntawm cov xwm txheej (tseem tsis yog thawj zaug hauv keeb kwm ntawm kev tshawb fawb?). Nyob rau hauv 1896, nws poob ib tug crystal ntawm silver nitrate AgNO.3 ntawm lub khob phaj coated nrog ib tug daws ntawm poov tshuaj dichromate (VI) K2Cr2O7 nyob rau hauv gelatin (Liesegang tau txaus siab rau kev yees duab, thiab dichromates tseem siv nyob rau hauv lub thiaj li hu ua noble tswv yim ntawm classical photography, piv txwv li, nyob rau hauv cov txheej txheem ntawm roj hmab thiab bromine). Concentric voj voog ntawm xim av precipitate ntawm nyiaj (VI) Ag chromate tsim nyob ib ncig ntawm lub lapis lazuli siv lead ua.2CRO4 txaus siab rau German chemist. Tus kws tshawb fawb tau pib txoj kev tshawb fawb ntawm qhov pom tshwm sim thiab yog li ntawd cov nplhaib tau raug hu ua nws.
Cov tshuaj tiv thaiv pom los ntawm Liesegang sib raug rau qhov sib npaug (sau hauv daim ntawv luv luv ionic):
Hauv kev daws teeb meem dichromate (los yog chromate), qhov sib npaug yog tsim los ntawm cov anions
, nyob ntawm cov tshuaj tiv thaiv ib puag ncig. Txij li nyiaj (VI) chromate tsawg soluble tshaj nyiaj (VI) dichromate, nws precipitates.
Nws ua thawj zaug los piav txog qhov tshwm sim pom. Wilhelm Friedrich Ostwald (1853-1932), tus yeej ntawm 1909 Nobel nqi zog hauv Chemistry. Tus German lub cev chemist tau hais tias nag lossis daus yuav tsum muaj supersaturation ntawm cov tshuaj thiaj li tsim crystallization nuclei. Ntawm qhov tod tes, kev tsim cov nplhaib yog txuam nrog qhov tshwm sim ntawm kev nthuav tawm ntawm ions hauv nruab nrab uas tiv thaiv lawv txoj kev txav (gelatin). Cov tshuaj lom neeg los ntawm txheej dej nkag mus tob rau hauv txheej gelatin. Cov ions ntawm cov "raug" reagent yog siv los ua ib tug precipitate. nyob rau hauv gelatin, uas ua rau depletion ntawm cov cheeb tsam tam sim ntawd nyob ib sab ntawm cov sediment (ions diffuse nyob rau hauv cov kev taw qhia ntawm txo concentration).
Liesegang rings hauv vitro
Vim yog qhov tsis tuaj yeem ntawm kev sib npaug nrawm ntawm cov concentrations los ntawm convection (sib tov ntawm cov kev daws teeb meem), puas yog cov reagent los ntawm cov txheej txheej aqueous sib tsoo nrog rau lwm thaj av uas muaj cov ntsiab lus siab txaus ntawm ions uas muaj nyob rau hauv gelatin, tsuas yog nyob ntawm qee qhov deb ntawm cov txheej txheem uas twb tau tsim lawm? qhov tshwm sim yog rov ua ntu zus. Yog li ntawd, Liesegang rings yog tsim los ntawm cov nag lossis daus cov tshuaj tiv thaiv nyob rau hauv cov xwm txheej ntawm kev sib xyaw nyuaj ntawm cov reagents. Koj puas tuaj yeem piav qhia cov txheej txheem txheej txheem ntawm qee cov zaub mov zoo sib xws? Diffusion ntawm ions tshwm sim nyob rau hauv ib tug ntom nruab nrab ntawm molten magma.
Lub ntiaj teb ringed nyob kuj yog qhov tshwm sim ntawm cov peev txheej tsawg. Lub voj voog ntawm dab ntxwg nyoog? tsim los ntawm nceb (los ntawm lub sij hawm immemorial nws tau suav hais tias ib tug kab ntawm qhov kev txiav txim ntawm "cov dab phem"), nws tshwm sim nyob rau hauv ib tug yooj yim txoj kev. Mycelium loj hlob nyob rau hauv tag nrho cov lus qhia (hauv av, tsuas yog fruiting lub cev pom nyob rau saum npoo). Tom qab ib pliag, cov av yuav sterilized nyob rau hauv qhov chaw? lub mycelium tuag tawm, tsuas yog nyob rau hauv periphery, tsim ib lub nplhaib-zoo li tus qauv. Kev siv cov khoom noj khoom haus hauv qee qhov chaw ntawm ib puag ncig tuaj yeem piav qhia lub nplhaib qauv ntawm cov kab mob thiab cov kab mob pwm.
Kev sim nrog Liesegang rings lawv tuaj yeem nqa tawm hauv tsev (ib qho piv txwv ntawm kev sim tau piav qhia hauv tsab xov xwm; ntxiv rau, hauv 8/2006 qhov teeb meem ntawm Młodego Technika, Stefan Sienkowski nthuav tawm Liesegang qhov kev sim thawj zaug). Txawm li cas los xij, nws tsim nyog them tus nqi ntawm cov neeg sim rau ntau lub ntsiab lus. Raws li txoj cai, Liesegang rings tuaj yeem tsim nyob rau hauv cov tshuaj tiv thaiv nag lossis daus (feem ntau ntawm lawv tsis tau piav qhia hauv cov ntaub ntawv, yog li peb tuaj yeem dhau los ua cov tho kev!), tab sis tsis yog txhua tus ntawm lawv ua rau cov txiaj ntsig xav tau thiab yuav luag txhua qhov sib xyaw ua ke ntawm reagents hauv gelatin thiab aqueous tov (cov lus qhia los ntawm tus sau, kev paub yuav zoo).
pwm ntawm txiv hmab txiv ntoo
Nco ntsoov tias gelatin yog cov protein thiab tawg los ntawm qee cov reagents (ces ib txheej gel tsis tsim). Ntau lub nplhaib yuav tsum tau txais los ntawm kev siv cov raj me me li sai tau (cov raj ntim cov iav tuaj yeem siv tau). Kev ua siab ntev yog qhov tseem ceeb, txawm li cas los xij, vim qee qhov kev sim siv sijhawm ntev heev (tab sis nws tsim nyog tos; cov nplhaib tsim tau yooj yim? Zoo nkauj!).
Txawm tias phenomenon ntawm creativity Liesegang rings tej zaum yuav zoo li peb tsuas yog xav paub txog tshuaj lom neeg (lawv tsis hais nws hauv tsev kawm), nws yog qhov dav heev. Puas yog qhov tshwm sim uas tau hais hauv tsab xov xwm yog qhov piv txwv ntawm ntau qhov tshwm sim? tshuaj oscillatory tshuaj tiv thaiv thaum lub sij hawm lub sij hawm hloov nyob rau hauv lub concentration ntawm lub substrate tshwm sim. Liesegang rings lawv yog qhov tshwm sim ntawm cov kev hloov pauv hauv qhov chaw. Ntawm kev txaus siab kuj yog cov tshuaj tiv thaiv uas qhia tau tias muaj kev hloov pauv hauv cov concentrations thaum lub sijhawm ua haujlwm, piv txwv li, kev hloov pauv ntawm cov concentrations ntawm glycolysis reagents, feem ntau yuav, ua rau lub sij hawm lom neeg ntawm cov kab mob nyob.
Saib kev paub:
Chemistry ntawm lub vev xaib
?Abyss? Hauv Is Taws Nem muaj ntau qhov chaw uas yuav txaus siab rau tus kws tshuaj. Txawm li cas los xij, qhov teeb meem loj zuj zus yog qhov overabundance ntawm cov ntaub ntawv luam tawm, qee zaum kuj tsis zoo. Tsis yog? yuav hais ntawm no qhov ci ntsa iab kwv yees ntawm Stanislav Lem, uas ntau tshaj 40 xyoo dhau los hauv nws phau ntawv ?? tshaj tawm tias kev nthuav dav ntawm cov ntaub ntawv xov xwm ib txhij txwv lawv qhov muaj.
Yog li ntawd, nyob rau hauv lub ces kaum ntawm chemistry muaj ib seem nyob rau hauv uas chaw nyob thiab cov lus piav qhia ntawm qhov nthuav tshaj plaws "tshuaj" chaw yuav tsum luam tawm. Muaj feem xyuam rau tsab xov xwm niaj hnub no? chaw nyob ua rau cov chaw piav txog Liesegang rings.
Thawj qhov haujlwm ntawm F. F. Runge hauv daim ntawv digital (cov ntaub ntawv PDF nws tus kheej muaj rau rub tawm ntawm qhov chaw nyob luv: http://tinyurl.com/38of2mv):
http://edocs.ub.uni-frankfurt.de/volltexte/2007/3756/.
Lub vev xaib nrog chaw nyob http://www.insilico.hu/liesegang/index.html Puas yog qhov kev lees paub tiag tiag ntawm kev paub txog Liesegang rings? keeb kwm ntawm kev tshawb pom, kev tshawb xav ntawm kev kawm thiab ntau cov duab.
Thiab thaum kawg, ib yam dab tsi tshwj xeeb? zaj duab xis qhia Ag nag los nag tsim2CRO4, ua hauj lwm ntawm ib tug tub kawm ntawv Polish, ib tug phooj ywg ntawm MT nyeem ntawv. Tau kawg, tshaj tawm hauv YouTube:
Nws tseem tsim nyog siv lub tshuab tshawb nrhiav (tshwj xeeb tshaj yog cov duab nraaj) los ntawm kev nkag mus rau cov ntsiab lus tsim nyog rau hauv nws: "Liesegang rings", "Liesegang bands" lossis tsuas yog "Liesegang rings".
Hauv kev daws teeb meem dichromate (los yog chromate), qhov sib npaug yog tsim los ntawm cov anions
thiab, nyob ntawm cov tshuaj tiv thaiv ntawm ib puag ncig. Txij li nyiaj (VI) chromate tsawg soluble tshaj nyiaj (VI) dichromate, nws precipitates.
Thawj qhov kev sim piav qhia qhov tshwm sim tau pom los ntawm Wilhelm Friedrich Ostwald (1853-1932), tus yeej ntawm Nobel nqi zog hauv Chemistry hauv 1909. Tus German lub cev chemist tau hais tias nag lossis daus yuav tsum muaj supersaturation ntawm cov tshuaj thiaj li tsim crystallization nuclei. Ntawm qhov tod tes, kev tsim cov nplhaib yog txuam nrog qhov tshwm sim ntawm kev nthuav tawm ntawm ions hauv nruab nrab uas tiv thaiv lawv txoj kev txav (gelatin). Cov tshuaj lom neeg los ntawm txheej dej nkag mus tob rau hauv txheej gelatin. Cov ions ntawm cov "raug" reagent yog siv los ua ib tug precipitate. nyob rau hauv gelatin, uas ua rau depletion ntawm cov cheeb tsam tam sim ntawd nyob ib sab ntawm cov sediment (ions diffuse nyob rau hauv cov kev taw qhia ntawm txo concentration). Vim yog qhov tsis yooj yim ntawm kev sib txig sib luag ntawm cov concentrations los ntawm convection (sib tov ntawm cov kev daws teeb meem), cov reagent los ntawm aqueous txheej collides nrog rau lwm cheeb tsam nrog ib tug txaus siab concentration ntawm ions uas muaj nyob rau hauv gelatin, tsuas yog nyob deb ntawm lub twb tsim txheej? qhov tshwm sim yog rov ua ntu zus. Yog li, Liesegang rings yog tsim los ntawm cov nag lossis daus cov tshuaj tiv thaiv ua haujlwm nyob rau hauv cov xwm txheej ntawm kev sib xyaw nyuaj ntawm cov reagents. Koj puas tuaj yeem piav qhia txog kev tsim cov txheej txheem txheej txheem ntawm qee cov zaub mov zoo sib xws? Diffusion ntawm ions tshwm sim nyob rau hauv ib tug ntom nruab nrab ntawm molten magma.
Lub ntiaj teb ringed nyob kuj yog qhov tshwm sim ntawm cov peev txheej tsawg. Lub voj voog ntawm dab ntxwg nyoog? tsim los ntawm nceb (los ntawm lub sij hawm immemorial nws tau suav hais tias ib tug kab ntawm qhov kev txiav txim ntawm "cov dab phem"), nws tshwm sim nyob rau hauv ib tug yooj yim txoj kev. Mycelium loj hlob nyob rau hauv tag nrho cov lus qhia (hauv av, tsuas yog fruiting lub cev pom nyob rau saum npoo). Tom qab ib pliag, cov av yuav sterilized nyob rau hauv qhov chaw? lub mycelium tuag tawm, tsuas yog nyob rau hauv periphery, tsim ib lub nplhaib-zoo li tus qauv. Kev siv cov khoom noj khoom haus hauv qee qhov chaw ntawm ib puag ncig tuaj yeem piav qhia lub nplhaib qauv ntawm cov kab mob thiab cov kab mob pwm.
Kev sim nrog Liesegang rings tuaj yeem nqa tawm hauv tsev (ib qho piv txwv ntawm kev sim tau piav qhia hauv tsab xov xwm; ntxiv rau, hauv qhov teeb meem ntawm Młodego Technika hnub tim 8/2006, Stefan Sienkowski nthuav tawm thawj Liesegang kev sim). Txawm li cas los xij, nws tsim nyog them tus nqi ntawm cov neeg sim rau ntau lub ntsiab lus. Raws li txoj cai, Liesegang rings tuaj yeem tsim nyob rau hauv cov tshuaj tiv thaiv nag lossis daus (feem ntau ntawm lawv tsis tau piav qhia hauv cov ntaub ntawv, yog li peb tuaj yeem dhau los ua cov tho kev!), tab sis tsis yog txhua tus ntawm lawv ua rau cov txiaj ntsig xav tau thiab yuav luag txhua qhov sib xyaw ua ke ntawm reagents hauv gelatin thiab aqueous tov (cov lus qhia los ntawm tus sau, kev paub yuav zoo). Nco ntsoov tias gelatin yog cov protein thiab tawg los ntawm qee cov reagents (ces ib txheej gel tsis tsim). Ntau lub nplhaib yuav tsum tau txais los ntawm kev siv cov raj me me li sai tau (cov raj ntim cov iav tuaj yeem siv tau). Kev ua siab ntev yog qhov tseem ceeb, txawm li cas los xij, vim qee qhov kev sim siv sijhawm ntev heev (tab sis nws tsim nyog tos; cov nplhaib tsim tau yooj yim? Zoo nkauj!).
Txawm hais tias qhov tsim ntawm Liesegang nplhaib yuav zoo li kev xav paub txog tshuaj lom neeg (nws tsis tau hais hauv tsev kawm), nws yog qhov dav heev. Puas yog qhov tshwm sim uas tau hais hauv tsab xov xwm yog qhov piv txwv ntawm ntau qhov tshwm sim? tshuaj oscillatory tshuaj tiv thaiv thaum lub sij hawm lub sij hawm hloov nyob rau hauv lub concentration ntawm lub substrate tshwm sim. Liesegang rings yog qhov tshwm sim ntawm cov kev hloov pauv hauv qhov chaw. Ntawm kev txaus siab kuj yog cov tshuaj tiv thaiv uas qhia tau tias muaj kev hloov pauv hauv cov concentrations thaum lub sijhawm ua haujlwm, piv txwv li, kev hloov pauv ntawm cov concentrations ntawm glycolysis reagents, feem ntau yuav, ua rau lub sij hawm lom neeg ntawm cov kab mob nyob.
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