Liesegang izindandatho? indalo ethakazelisayo

"Umjikelezo kaDeveli"

Sicela ubheke izithombe ezimbalwa ezibonisa izinto eziphilayo namasampula emvelo engaphili: iqoqo lamagciwane endaweni ye-agar medium, isikhunta esikhula esithelweni, isikhunta otshanini bedolobha namaminerali - i-agate, i-malachite, i-sandstone. Zifana ngani zonke izinto? Lesi isakhiwo sabo, esihlanganisa (okuningi noma okuncane okuchazwe kahle) imibuthano egxilile. Osokhemisi bayawabiza Amasongo kaLiesegang.

Igama lalezi zakhiwo livela egameni lomtholi? URaphael Edouard Liesegang, nakuba ebengaqali ukuzichaza. Lokhu kwenziwa ngo-1855 nguFriedlieb Ferdinand Runge, owayehileleke, phakathi kwezinye izinto, ekwenzeni ukusabela kwamakhemikhali ephepheni lokuhlunga. Idalwe usokhemisi waseJalimane? Izithombe zokuzikhulela wena? () ngokuqinisekile zingabhekwa njengezindandatho zokuqala ze-Liesegang ezitholiwe, futhi indlela yokuzilungiselela i-chromatography yephepha. Nokho, ukutholakala akuzange kuqashelwe emhlabeni wesayensi? URunge wakwenza ngaphambi kwengxenye yekhulu leminyaka ngaphambi kwesimiso (isazi sezitshalo saseRussia uMikhail Semyonovich Tsvet, owayesebenza eWarsaw ekuqaleni kwekhulu lama-XNUMX, ungumsunguli owaziwayo we-chromatography). Nokho, leli akulona icala lokuqala elinjalo emlandweni wesayensi; ngoba ngisho nezinto ezitholakele kumele "zifike ngesikhathi."

URaphael Eduard Liesegang (1869-1947)? Usokhemisi waseJalimane nosomabhizinisi embonini yezithombe. Njengososayensi, wafunda i-chemistry yama-colloids nezinto zezithombe. Ubedume ngokuvundulula izinhlaka ezaziwa ngama-Liesegang rings.

Udumo lomtholi lwatholwa ngu-R. E. Liesegang, owasizwa inhlanganisela yezimo (futhi hhayi okokuqala emlandweni wesayensi?). Ngo-1896, wehlisa i-crystal ye-nitrate yesiliva i-AgNO.₃ epuleti lengilazi elihlanganiswe nesisombululo se-potassium dichromate (VI) K₂Cr₂O₇ nge-gelatin (u-Liesegang wayenesithakazelo ezithombeni, futhi ama-dichromates asasetshenziswa kulokho okubizwa ngokuthi amasu ahloniphekile wezithombe zakudala, isibonelo, kumasu enjoloba ne-bromine). Imibuthano egxilile yemvula ensundu yesiliva(VI)Ag chromate yakheke eduze kwekristalu ye-lapis lazuli.₂ICO₄ wathakasela usokhemisi waseJalimane. Usosayensi waqala ucwaningo oluhlelekile lwento ephawuliwe ngakho-ke izindandatho zagcina ziqanjwe ngaye.

Ukusabela okwabonwa u-Liesegang kuhambisana nezibalo (ezibhalwe ngendlela efushanisiwe ye-ionic):

Kusixazululo se-dichromate (noma i-chromate), ukulingana kuyasungulwa phakathi kwama-anions

, kuye ngokusabela kwendawo ezungezile. Ngenxa yokuthi isiliva(VI) chromate incibilika kancane kunesiliva(VI) dichromate, iyashona.

Wenza umzamo wokuqala ukuchaza lesi sigameko esibonwe. UWilhelm Friedrich Ostwald (1853-1932), owawina uMklomelo KaNobel eKhemistry ngo-1909. Isazi samakhemikhali esingokomzimba saseJalimane sathi imvula idinga i-supersaturation yesisombululo ukuze kwakhiwe i-crystallization nuclei. Ngakolunye uhlangothi, ukwakheka kwezindandatho kuhlotshaniswa nokwenzeka kokusakazwa kwama-ion endaweni evimbela ukunyakaza kwawo (i-gelatin). Inhlanganisela yamakhemikhali evela ongqimbeni lwamanzi ingena ijule ongqimbeni lwe-gelatin. Ama-ion we-reagent "evaleleke" asetshenziselwa ukwakha imvula. ku-gelatin, okuholela ekuncipheni kwezindawo ezisondelene ngokushesha ne-sediment (ama-ion ahlakazeka ngendlela yokunciphisa ukugxila).

U-Liesegang ukhala ku-vitro

Ngenxa yokungenzeki kokulinganisa okusheshayo kokugxilisa ingqondo nge-convection (ukuxutshwa kwezixazululo), ingabe i-reagent evela ongqimbeni olunamanzi ishayisana nesinye isifunda esinomthamo omkhulu ngokwanele wama-ion aqukethwe ku-gelatin, kuphela ebangeni elithile ukusuka kungqimba oseluvele lwakhiwe? lesi simo siphindaphindwa ngezikhathi ezithile. Ngakho-ke, amasongo e-Liesegang akhiwa ngenxa yokusabela kwezulu okwenziwa ngaphansi kwezimo zokuxuba okunzima kwama-reagents. Ungakwazi yini ukuchaza ukwakheka kwezingqimba zamanye amaminerali ngendlela efanayo? Ukusatshalaliswa kwama-ion kwenzeka endaweni eminyene ye-magma encibilikisiwe.

Umhlaba ophilayo onezindatshana nawo uwumphumela wezinsiza ezilinganiselwe. Umbuthano kasathane? eyakhiwe ngamakhowe (kusukela kudala kwakubhekwa njengomphumela wesenzo "semimoya emibi"), ivela ngendlela elula. I-Mycelium ikhula kuzo zonke izinhlangothi (ngaphansi komhlaba, imizimba yezithelo kuphela ibonakala phezulu). Ngemva kwesikhashana, inhlabathi iba inzalo phakathi nendawo? i-mycelium iyafa, isele kuphela ku-periphery, yakha isakhiwo esimise njengendandatho. Ukusetshenziswa kwemithombo yokudla ezindaweni ezithile zemvelo nakho kungachaza ukwakheka kwendandatho yamakoloni amagciwane kanye nesikhunta.

Ukuhlola nge Amasongo kaLiesegang zingenziwa ekhaya (isibonelo sokuhlola sichazwe esihlokweni; ngaphezu kwalokho, kumagazini we-Młodego Technika wangomhla zi-8/2006, uStefan Sienkowski wethula ukuhlolwa kwasekuqaleni kukaLiesegang). Kodwa-ke, kufanelekile ukunaka abahloli kumaphuzu amaningana. Ngokweqile, izindandatho ze-Liesegang zingakhiwa kunoma yikuphi ukusabela kwezulu (iningi lazo alichazwanga ezincwadini, ngakho-ke singaba amaphayona!), Kodwa akuzona zonke eziholela kumphumela oyifunayo futhi cishe zonke izinhlanganisela ezingenzeka zama-reagents ku-gelatin kanye isixazululo samanzi (okuphakanyiswe umbhali, isipiliyoni sizoba kuhle).

isikhunta ezithelweni

Khumbula ukuthi i-gelatin iyiphrotheni futhi idilizwa amanye ama-reagents (khona-ke ungqimba lwejeli alwakhiwe). Amaringi aphinyiselwe kakhudlwana kufanele atholakale kusetshenziswa amashubhu okuhlola mancane ngangokunokwenzeka (amashubhu engilazi avaliwe nawo angasetshenziswa). Ukubekezela kuyisihluthulelo, nokho, njengoba okunye ukuhlola kudla isikhathi (kodwa kuwufanele ukulinda; izindandatho ezakhiwe kahle zilula? Zinhle!).

Nakuba lo mkhuba wokusungula Amasongo kaLiesegang kungase kubonakale kithi ilukuluku lamakhemikhali kuphela (abakhulumi ngakho ezikoleni), lisakazeke kakhulu ngokwemvelo. Ingabe isenzakalo esishiwo esihlokweni siyisibonelo sento ebanzi kakhulu? ukusabela kwe-chemical oscillatory lapho kwenzeka izinguquko ngezikhathi ezithile ekugxilweni kwe-substrate. Amasongo kaLiesegang ziwumphumela walokhu kuguquguquka komkhathi. Okuthakazelisayo futhi ukusabela okubonisa ukushintshashintsha kokugxilisa ingqondo phakathi nenqubo, isibonelo, izinguquko ngezikhathi ezithile ekugxilweni kwama-reagents e-glycolysis, okungenzeka ukuthi, okungaphansi kwewashi lebhayoloji lezinto eziphilayo.

Bona ukuzizwisa:

Ikhemistri kuwebhu

?kwalasha? I-inthanethi iqukethe izingosi eziningi ezingase zibe nesithakazelo kusokhemisi. Nokho, inkinga ekhulayo ukuchichima ngokweqile kwedatha eshicilelwe, ngezinye izikhathi futhi enekhwalithi engabazekayo. Hhayi? uzocaphuna lapha izibikezelo ezihlakaniphile zikaStanislav Lem, eminyakeni engaphezu kwengu-40 edlule encwadini yakhe ?? yamemezela ukuthi ukunwetshwa kwezinsiza zolwazi kanyekanye kunciphisa ukutholakala kwazo.

Ngakho-ke, ekhoneni lamakhemikhali kukhona isigaba lapho amakheli nezincazelo zezindawo ezithakazelisa kakhulu "zamakhemikhali" zizoshicilelwa. Ihlobene nesihloko sanamuhla? amakheli aholela kumasayithi achaza izindandatho ze-Liesegang.

Umsebenzi wokuqala we-F. F. Runge ngefomu ledijithali (ifayela le-PDF ngokwalo liyatholakala ukuze lidawunilodwe ekhelini elifushanisiwe: http://tinyurl.com/38of2mv):

http://edocs.ub.uni-frankfurt.de/volltexte/2007/3756/.

Iwebhusayithi enekheli http://www.insilico.hu/liesegang/index.html iyiqoqo langempela lolwazi mayelana nezindandatho ze-Liesegang? umlando wokutholwa, imibono yezemfundo nezithombe eziningi.

Futhi ekugcineni, okuthile okukhethekile? ifilimu ekhombisa ukwakheka kweringi yezulu ye-Ag₂ICO₄, umsebenzi womfundi wasePoland, untanga wabafundi beMT. Yebo, kuthunyelwe ku-YouTube:

Kuyafaneleka futhi ukusebenzisa injini yokusesha (ikakhulukazi eyisithombe) ngokufaka amagama angukhiye afanelekile kuyo: “Izindandatho ze-Liesegang”, “amabhendi e-Liesegang” noma “ama-Liesegang rings”.

Kusixazululo se-dichromate (noma i-chromate), ukulingana kuyasungulwa phakathi kwama-anions

futhi, kuye ngokusabela kwemvelo. Ngenxa yokuthi isiliva(VI) chromate incibilika kancane kunesiliva(VI) dichromate, iyashona.

Umzamo wokuqala wokuchaza lesi senzakalo esiphawuliwe senziwa uWilhelm Friedrich Ostwald (1853-1932), owawina uMklomelo KaNobel kuKhemistry ngo-1909. Isazi samakhemikhali esingokomzimba saseJalimane sathi imvula idinga i-supersaturation yesisombululo ukuze kwakhiwe i-crystallization nuclei. Ngakolunye uhlangothi, ukwakheka kwezindandatho kuhlotshaniswa nokwenzeka kokusakazwa kwama-ion endaweni evimbela ukunyakaza kwawo (i-gelatin). Inhlanganisela yamakhemikhali evela ongqimbeni lwamanzi ingena ijule ongqimbeni lwe-gelatin. Ama-ion we-reagent "evaleleke" asetshenziselwa ukwakha imvula. ku-gelatin, okuholela ekuncipheni kwezindawo ezisondelene ngokushesha ne-sediment (ama-ion ahlakazeka ngendlela yokunciphisa ukugxila). Ngenxa yokungenzeki kokulinganisa okusheshayo kokugxilisa ingqondo nge-convection (ukuxutshwa kwezixazululo), ingabe i-reagent esuka kungqimba olunamanzi ishayisana nesinye isifunda esinomthamo omkhulu ngokwanele wama-ion aqukethwe ku-gelatin, kuphela kude nongqimba oseluvele lwakhiwe? lesi simo siphindaphindwa ngezikhathi ezithile. Ngakho-ke, amasongo e-Liesegang akhiwa ngenxa yokusabela kwezulu okwenziwa ngaphansi kwezimo zokuxuba okunzima kwama-reagents. Ungakwazi yini ukuchaza ukwakheka kwesakhiwo esinezingqimba zamanye amaminerali ngendlela efanayo? Ukusatshalaliswa kwama-ion kwenzeka endaweni eminyene ye-magma encibilikisiwe.

Umhlaba ophilayo onezindatshana nawo uwumphumela wezinsiza ezilinganiselwe. Umbuthano kasathane? eyakhiwe ngamakhowe (kusukela kudala kwakubhekwa njengomphumela wesenzo "semimoya emibi"), ivela ngendlela elula. I-Mycelium ikhula kuzo zonke izinhlangothi (ngaphansi komhlaba, imizimba yezithelo kuphela ibonakala phezulu). Ngemva kwesikhashana, inhlabathi iba inzalo phakathi nendawo? i-mycelium iyafa, isele kuphela ku-periphery, yakha isakhiwo esimise njengendandatho. Ukusetshenziswa kwemithombo yokudla ezindaweni ezithile zemvelo nakho kungachaza ukwakheka kwendandatho yamakoloni amagciwane kanye nesikhunta.

Ukuhlolwa ngezindandatho ze-Liesegang kungenziwa ekhaya (isibonelo sokuhlolwa sichazwe esihlokweni; ngaphezu kwalokho, kumagazini we-Młodego Technika wangomhla zi-8/2006, uStefan Sienkowski wethula ukuhlolwa kwasekuqaleni kwe-Liesegang). Kodwa-ke, kufanelekile ukunaka abahloli kumaphuzu amaningana. Ngokweqile, izindandatho ze-Liesegang zingakhiwa kunoma yikuphi ukusabela kwezulu (iningi lazo alichazwanga ezincwadini, ngakho-ke singaba amaphayona!), Kodwa akuzona zonke eziholela emphumeleni oyifunayo futhi cishe zonke izinhlanganisela ezingenzeka zama-reagents ku-gelatin futhi isixazululo samanzi (okuphakanyiswe umbhali, isipiliyoni sizoba kuhle). Khumbula ukuthi i-gelatin iyiphrotheni futhi idilizwa amanye ama-reagents (khona-ke ungqimba lwejeli alwakhiwe). Amaringi aphinyiselwe kakhudlwana kufanele atholakale kusetshenziswa amashubhu okuhlola mancane ngangokunokwenzeka (amashubhu engilazi avaliwe nawo angasetshenziswa). Ukubekezela kuyisihluthulelo, nokho, njengoba okunye ukuhlola kudla isikhathi (kodwa kuwufanele ukulinda; izindandatho ezakhiwe kahle zilula? Zinhle!).

Nakuba ukwakheka kweringi ye-Liesegang kungase kubonakale njengelukuluku lamakhemikhali (akushiwo ezikoleni), kusakazeke kakhulu ngokwemvelo. Ingabe isenzakalo esishiwo esihlokweni siyisibonelo sento ebanzi kakhulu? ukusabela kwe-chemical oscillatory lapho kwenzeka izinguquko ngezikhathi ezithile ekugxilweni kwe-substrate. Amaringi e-Liesegang awumphumela walokhu kuguquguquka kwesikhala. Okuthakazelisayo futhi ukusabela okubonisa ukushintshashintsha kokugxilisa ingqondo phakathi nenqubo, isibonelo, izinguquko ngezikhathi ezithile ekugxilweni kwama-reagents e-glycolysis, okungenzeka ukuthi, okungaphansi kwewashi lebhayoloji lezinto eziphilayo.

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