Dawb lead: lub zog, siv, siv, raug mob rau kev kho mob

Mineral xim dawb, ua rau lub hauv paus ntawm cov hlau lead, npe hu ua tom qab lub mineral yog muaj nyob rau hauv lawv cov muaj pes tsawg leeg - dawb lead. Nyob rau hauv lub teb chaws, lub sij hawm thiab txoj kev raug txhuas yog variously hu ua: psimition, Dutch, cerussite, nyiaj los yog cia li nyiaj ua npuas ncauj, Klagenfurt, Venetian dawb, dawb huv dawb lead thiab lwm tus neeg.

Lub keeb kwm ntawm tshwm sim

Rau cov thawj lub sij hawm dawb lead tau piav nyob rau hauv lub ntawmv ntawm lub Greek txawj sau ntawv Dioscorides nyob rau hauv IV xyoo pua BC. Twb paub txog lub thaj chaw ntawm cov hlau lead thiab yuav tawm ntawm nws los tsim cov xim. Ib me ntsis tom qab whitewash raug technology, los yog, raws li lawv hu ua lawv, cerussa, tau piav txog tus Roman sau ntawv xws li Vitruvius, Pliny thiab Theophrastus. Lub "tshiab" lub teeb ntawm dawb lead rau cov thawj lub sij hawm nyob rau hauv lub Netherlands nyob rau hauv cov Nrab Hnub nyoog. Hoobkas zus tau tej cov dawb heev sai sai nrhiav tau ib tug ntau tis, thiab lawv tau yog tas li loj hlob. Dua li no, tus paub txog Bergman tsuas mus rau thaum xaus ntawm lub XVIII xyoo pua, muaj peev xwm los qhia cov tshuaj nyob tus yeees ntawm cov dawb.

Raws li rau Russia, lub keeb kwm ntawm kev siv thiab cov siv thiab ua cov dawb lead yog tsis li qub, ib puas xyoo dhau los, lawv pib ua tau rau peb. Ua raws li xim nyob rau hauv loj qhov ntau nyob rau hauv Yaroslavl, uas yog xam rau qhov chaw ntawm zus tau tej cov whitewash. Rau hnub tim, muaj ntau ntau factories koom nyob rau hauv qhov siv thiab ua dawb-paub hom uas yog nrov thoob ntiaj teb.

kheej ntawm daim ntawv thov

Koj yuav siv tsis tau dawb lead raws li ib tug hnyav rau cov lwm yam xim. Tib yam siv rau lawv cov kev siv nyob rau hauv painting ua hauj lwm vim hais tias ntawm lub high school toxicity ntawm cov khoom. Nyob rau hauv exceptional mob ntawm kev siv ntawm cov hlau lead-raws li dawb xim rau cov hniav hlau.

Yog hais tias, txawm li cas los, muaj yog kev siv ntawm cov dawb lead nyob rau hauv lub chaw ua hauj lwm, nws yog tsim nyog nruj kev ua raws li kev ruaj ntseg cov kev cai kho nyob rau hauv cov ntaub ntawv ntawm qhov kev siv ntawm tej tshuaj. Vim hais tias ntawm qhov teeb meem los ntawm tib neeg lub cev, txawm raws li ib feem ntawm cov xim muaj hlau nws yog txwv tsis pub siv dawb lead.

Vim lub high toxicity siv dawb tswj ntawm lub PatientsÕ theem. Yog li, cov kev cai ntawm 1909 thiab 1926 cuam tshuam tus ntse poob nyob rau hauv lub xyoo ntau lawm ntawm cov xim tsev nyob rau hauv Fabkis. Kaum Ob tug xim factories nyob rau hauv lub teb chaws no txhua xyoo ua ntau tshaj 20 000 tonnes ntawm Whiting nyob rau hauv lub tam sim no lub sij hawm, tus nqi tsis pub tshaj 1,000 tonnes. Cov kev cai yog, hmoov tsis, tsuas yog thov mus rau lub chaw uas zoo heev ntawm Fabkis, nyob rau hauv lub lwm lub teb chaws, siv cov dawb lead tsis yog los ntawm kev cai lij choj.

Thaj chaw ntawm dawb lead

Lawv yog ua nyob rau hauv daim ntawv ntawm hnyav dawb hmoov muaj ib tug granular cov qauv. Thaum kis tau tus pa acetic acid mus rau daim ntawv hlau thiab dawb lead. Thas xim rau lawv, lawv txiav txim los ntawm lub npe, dawb. Vim qhov xwm ntawm tus ntau lawm txheej txheem rau qhov kawg khoom no muaj cov ib tug me me npaum li cas ntawm cov hmoov txhuas qab zib. Qhov no muaj feem xyuam rau tus ntxhiab ntawm cov dawb txhuas, lawv muaj me ntsis sourish tsw, thiab tus piv ntawm acetic yooj yim lead ntsev yuav tsum tsis pub tshaj 1% ntawm tag nrho cov impurities.

Mineral xim, uas yog tsim los ntawm cov dawb txhuas, muaj lub siab ua tej qho hwj chim thiab luv luv kom qhuav lub sij hawm. Mus txog 10% ntawm tag nrho cov luj ntawm tus number case ntawm lawv cov roj haum. Tawm sab nraud Dawb sai sai solidify, thiab qhov no tshwm sim thoob plaws hauv lub thickness ntawm cov xim muaj hlau txheej. Nws yog ua tsaug rau qhov no zoo li uas cog noob nyob rau hauv painting nyob rau hauv multilayer technology thiab zus tau tej cov roj primers dawb lead.

Muaj pes tsawg leeg, thiab chaw pib lub peev xwm rau ceev ceev kom qhuav ntawm tus number case yog yooj yim pauv mus rau lwm yam ntaub ntawv, nrog rau cov tshwm sim hais tias txawm qeeb-qhuav number case rau sai sai qhuav tawm thoob plaws nws txheej. Ntawm kev nqi yog kawm tau rau podmalevki li zoo tagnrho rau tom ntej uas tseg tau, tus zoo txuam nrog tom ntej khaubncaws sab nraud povtseg thiab tsis keej.

Lows nyob rau hauv cov kev siv ntawm cov dawb lead

Sib nrug los ntawm lub cuab kev pab cuam ntawm txoj kev siv cov dawb txhuas, lawv muaj ib tug xov tooj ntawm ceeb disadvantages.

Thawj thiab foremost nws muaj nqis ntsoov teev lub siab toxicity ntawm cov hmoov. Thaum muab tshuaj ntxuav tag nrho cov kev ruaj ntseg cov kev cai yuav tsum tau ua raws li, nyob rau hauv kev txiav txim, yog li ntawd lub hmoov yog tsuag. Nws yog lub npe hu tsis tau tsuas yog rau tus neeg mob mob lom, tab sis kuj tuag taus.

Dawb lead yog tau hloov lawv lub teeb. Thaum raug rau hydrogen sulfide xim nws thawj pib loj hlob xim av, thiab ces tag puv dub. Qhov no tshwm sim yog hais tias ib feem ntawm ib tug tsis txaus tus naj npawb ntawm dawb phau ntawv lub caij. Txawm li cas los, txoj kev no yog reversible. Rau thawj zaug tshaaj pleev xim rau saum npoo hom xim yuav tsum kho nrog hydrogen peroxide, muaj peev xwm ntawm transforming lub dub lead sulphide rau hauv sulphate dawb.

Nyob rau hauv ib tug alkaline ib puag ncig, dawb heev tsis ruaj tsis khov, uas yog vim li cas lawv yuav tsis haum rau alkaline tempera thiab xeeb tub.

Nyob rau hauv nrag xws tseem tau pom. Dawb taug txhuas, linseed roj pounded nrog, muaj tus muaj peev xwm mus hloov lub ntiaj teb no. Yog hais tias daim duab yog muab deb ntawm cov qhov rai thiab yog raws kev coj kom lub phab ntsa xim raws li nyob dawb lead daj, tab sis yog tau rov qab mus rau tus thawj xim, thaum yog hais tias nws yog raug ncaj qha tshav ntuj.

Ntau ntawm cov dawb

Rau hnub tim, muaj ntau hom ntawm dawb. Lead, zinc thiab titanium yog cov feem ntau.

Coj - cov hlob, lawv feem ntau siv lub qub ntxias. Advantage ntawm lawv yog hais tias nws yuav tau mus thov nyob rau hauv cov pob tshab khaubncaws sab nraud povtseg, thiab cov xim muaj hlau dries sai sai heev. Nws muaj ib tug saj zawg zog qauv thiab ruaj khov. Tab sis lub ntsiab drawback yog nws toxicity.

Titanium dawb. Lawv yog cov tsis muaj tsawg nrov nrog nyuab thiab tus yam ntxwv yog zoo li cov dawb lead. Qhov no kob vuam yog qhov whitest laus, tab sis nws disadvantage yog hais tias nws yog kiag li pob tshab thiab tag nyob rau lwm tones.

Cov no yog cov nrov heev nrog dawb tais diav ntim chaws masters. Lawv cuam tshuam ncaj qha nyob rau hauv cov av nplaum, thiab yog hais tias yog tsis txaus, ces thov ib tug nyias txheej nyob rau hauv sab saum toj ntawm lwm tus.

Zinc oxide. Lawv yog cov tsis raws li tuab li titanium dawb , thiab yog li ntawd lawv siv rau toning thiab thov tshab khaubncaws sab nraud povtseg. Lub downside ntawm no xim tsuas yog ib tug ntev qhuav lub sij hawm.

Dutch qauv

Qhov no yog tus thawj thiab feem ntau ancient txoj kev dawb lead ntau lawm. Rau tus txheej txheem no, cov hlau lead hauv cov phiaj 2-3 mm dav sawb yog txiav mus rau hauv ib tug ntev ntawm 6 cm muab tso nyob rau hauv ib tug glazed earthenware huam, yog li displacing kauv. Huam yuav tsum txog 1 liter, thiab ib qhov siab ntawm 20 cm. Thereto ntxiv 250 ml ntawm vinegar. Cov huam yog muab tso rau hauv kab ntawm cib koob yees duab thiab interspersed nrog khaubncaws sab nraud povtseg ntawm nees quav, yog ntxiv. Tom qab txheej shrouded nees quav, nws yog teem rau lub thawj txheej ntawm pots, lawv yuav them rau sab saum toj nrog cov hlau lead hauv cov phiaj thiab cov laug cam, rau tej qhov chaw ntawm lub huam kuj muaj nrog quav. Yog li huam yog teem mus txog rau lub sab saum toj khaubncaws sab nraud povtseg.

Thaum lub sij hawm quav fermentation generates tshav kub, uas txhawb nqa lub evaporation ntawm acetic acid. Thaum catalyzing oxygen los ntawm cov pa lead-ua acetic ntsev, yog hloov dua siab tshiab rau hauv uglesvintsovuyu, uas yog cov dawb lead. Tus txheej txheem ntawm kev sib cais ntawm cov dawb los ntawm cov hmoov txhuas hauv cov phiaj ntawm cov feem ntau laborious, feem ntau koom nyob rau hauv no siv lub tshuab. Feem ntau cov lug siv rau lub hom phiaj no yog ib tug mountainous ntaus ntawv.

German qauv

Qhov txawv ntawm tus txheej txheem ntawm German Dutch xwb nyob rau hauv cov ntsiab lus. Lead los xij tsis cuam tshuam nyob rau hauv lub huam, thiab yog dai nyob rau hauv cib thiab ntoo hlwb. Ib tug ntxiv txheej txheem effects acetic acid thiab cov pa tib yam. Feem ntau cov feem ntau cov qauv no yog siv Major tshuab.

Fabkis txoj

Tenar twb npaj siab los ntawm qhov Fabkis txoj kev raug dawb lead. Rau nws yog manufactured thawj tov acetic lead ntsev, thiab ces los ntawm kev uas cov pa roj carbon dioxide yog dhau lawm. Raws li ib tug tshwm sim, raug zam dawb, thiab qhov nruab nrab acetic Lead ntsev nyob rau hauv cov tshuaj. Qhov no tus txheej txheem yog tas mus li, raws li nyob rau hauv ib tug siv tshuaj redissolved litharge, txoj kev ua ib tug yooj yim ntsev.

English txoj kev

Qhov no txoj kev ntawm extracting dawb lead yog ntau thiab yog li ntawd siv tsawg ntev los no. Cov kab rov tav drums muab tso litharge, moistened nrog ib tug daws ntawm 1% lead qab zib. Muaj nws siv agitator rotates. Nyob rau hauv cov ntaub ntawv no, cov pa roj carbon dioxide kwj tiav.

Rau tus txheej txheem no, nws tseem ceeb heev uas nyob rau hauv lub litharge tsis muaj impurities, los yog dawb tej zaum yuav tau ib tug undesirable xim.