43. Yiziphi izinyathelo zokuphepha zokusebenzisa ama-electrode engilazi?
⑴Inani le-pH elingaba nguziro le-electrode yengilazi kufanele libe phakathi kwebanga lesilawuli sokuma se-acidimitha efanayo, futhi akumele lisetshenziswe ezixazululweni ezingenamanzi. Lapho i-electrode yengilazi isetshenziswa okokuqala noma iphinda isetshenziswa ngemva kokushiywa ingasetshenziswa isikhathi eside, isibani sengilazi kufanele sicwiliswe emanzini acwengekile amahora angaphezu kwangu-24 ukuze sakhe ungqimba oluhle lwe-hydration. Ngaphambi kokusetshenziswa, hlola ngokucophelela ukuthi i-electrode isesimweni esihle yini, isibani seglasi kufanele singabi nemifantu namabala, futhi i-electrode yereferensi yangaphakathi kufanele ifakwe emanzini okugcwalisa.
⑵ Uma kukhona amabhamuza esixazululweni sokugcwalisa sangaphakathi, nyakazisa i-electrode ukuze uvumele amabhamuza agcwale, ukuze kube nokuxhumana okuhle phakathi kwe-electrode yesithenjwa yangaphakathi nesixazululo. Ukuze ugweme ukulimala kwesibani seglasi, ngemva kokugeza ngamanzi, ungasebenzisa iphepha lokuhlunga ukuze ubambe ngokucophelela amanzi ahlanganiswe ne-electrode, futhi ungawasuli ngamandla. Uma ifakiwe, ingilazi yengilazi ye-electrode yengilazi iphakeme kancane kune-electrode eyireferensi.
⑶Ngemva kokulinganisa amasampula amanzi aqukethe uwoyela noma izinto ezifakwe emulsified, hlanza i-electrode ngesihlanzi namanzi ngesikhathi. Uma i-electrode ikalwa ngosawoti wezinto ezingaphili, cwilisa i-electrode ku-(1+9) i-hydrochloric acid. Ngemuva kokuthi isikali sihlakazekile, sihlanza kahle ngamanzi bese usibeka emanzini a-distilled ukuze usetshenziswe kamuva. Uma umphumela wokwelapha ongenhla ungagculisi, ungasebenzisa i-acetone noma i-ether (i-ethanol ephelele ayikwazi ukusetshenziswa) ukuyihlanza, bese uphatha ngendlela engenhla, bese ucwilisa i-electrode emanzini acwecwe ubusuku bonke ngaphambi kokusetshenziswa.
⑷ Uma namanje kungasebenzi, ungaphinda ucwilise kusisombululo sokuhlanza i-chromic acid imizuzu embalwa. I-Chromic acid iyasebenza ekususeni izinto ezikhangisiwe endaweni engaphandle yengilazi, kodwa inobubi bokuphelelwa ngamanzi emzimbeni. Ama-Electrode aphathwa nge-chromic acid kufanele acwiliswe emanzini ngobusuku bonke ngaphambi kokuthi asetshenziselwe ukukala. Njengendlela yokugcina, i-electrode ingacwiliswa kusisombululo esingu-5% se-HF imizuzwana engu-20 ukuya kwangu-30 noma kusixazululo se-ammonium hydrogen fluoride (NH4HF2) iminithi elingu-1 ukuze uthole ukwelashwa kokugqwala okusesilinganisweni. Ngemva kokucwiliswa emanzini, yihlanza ngokugcwele ngamanzi ngokushesha, bese uyicwilisa emanzini ukuze isetshenziswe kamuva. . Ngemuva kokwelashwa okunjalo okunzima, impilo ye-electrode izothinteka, ngakho-ke lezi zindlela ezimbili zokuhlanza zingasetshenziswa kuphela njengenye indlela yokulahla.
44. Yiziphi izimiso nezinyathelo zokuphepha zokusebenzisa i-calomel electrode?
⑴I-calomel electrode iqukethe izingxenye ezintathu: i-metallic mercury, i-mercury chloride (calomel) nebhuloho likasawoti le-potassium chloride. Ama-ion e-chloride ku-electrode avela kusisombululo se-potassium chloride. Lapho ukugcwala kwesisombululo se-potassium chloride kungashintshi, amandla e-electrode ahlala esezingeni elithile lokushisa, kungakhathaliseki ukuthi inani le-pH lamanzi. Isixazululo se-potassium chloride ngaphakathi kwe-electrode singena ngebhuloho likasawoti (i-ceramic sand core), okwenza ibhethri lokuqala liqhube.
⑵ Uma sisetshenziswa, isivalo senjoloba senozi ohlangothini lwe-electrode kanye nesivalo senjoloba ekugcineni esingezansi kufanele kususwe ukuze isisombululo sebhuloho likasawoti sikwazi ukugcina izinga elithile lokugeleza nokuvuza ngamandla adonsela phansi futhi kugcinwe ukufinyelela esixazululweni. ukukalwa. Uma i-electrode ingasebenzi, isivalo senjoloba kanye nesivalo senjoloba kufanele kubekwe endaweni ukuvimbela ukuhwamuka nokuvuza. Ama-electrode e-Calomel angazange asetshenziswe isikhathi eside kufanele agcwaliswe ngesisombululo se-potassium chloride futhi afakwe ebhokisini le-electrode ukuze agcinwe.
⑶ Akufanele kube namabhamuza esixazululweni se-potassium chloride ku-electrode ukuvimbela ukujikeleza okufushane; amakristalu ambalwa e-potassium chloride kufanele agcinwe esixazululweni ukuze kuqinisekiswe ukugcwala kwesisombululo se-potassium chloride. Kodwa-ke, akufanele kube namakristalu amaningi e-potassium chloride, ngaphandle kwalokho angase avimbe indlela eya esixazululweni esilinganiswayo, okuholela ekufundweni okungajwayelekile. Ngesikhathi esifanayo, ukunakwa kufanele futhi kukhokhwe ekuqedeni ama-bubbles emoyeni ebusweni be-calomel electrode noma endaweni yokuxhumana phakathi kwebhuloho likasawoti namanzi. Uma kungenjalo, kungase futhi kubangele ukuba isifunda sokulinganisa siphuke futhi ukufundwa kungafundeki noma kungazinzi.
⑷Ngesikhathi sokulinganisa, izinga loketshezi lesixazululo se-potassium chloride ku-calomel electrode kufanele libe phezulu kuneleveli yoketshezi yesisombululo esilinganisiwe ukuze kuvinjelwe uketshezi olulinganisiwe ukuthi lungasakazeki ku-electrode futhi luthinte amandla e-calomel electrode. Ukusabalalisa kwangaphakathi kwama-chlorides, ama-sulfides, ama-complexing agents, usawoti wesiliva, i-potassium perchlorate nezinye izingxenye eziqukethwe emanzini kuzothinta amandla e-calomel electrode.
⑸Lapho izinga lokushisa lishintshashintsha kakhulu, ushintsho olungaba khona lwe-calomel electrode luba ne-hysteresis, okungukuthi, izinga lokushisa liyashintsha ngokushesha, amandla e-electrode ashintsha kancane, futhi kuthatha isikhathi eside ukuthi amandla e-electrode afinyelele ukulingana. Ngakho-ke, zama ukugwema izinguquko ezinkulu ekushiseni lapho ukala. .
⑹ Naka ukuvimbela i-calomel electrode ceramic sand core ukuthi ingavinjelwa. Naka ukunaka okukhethekile ekuhlanzeni okufika ngesikhathi ngemuva kokulinganisa izixazululo ze-turbid noma izixazululo ze-colloidal. Uma kukhona abalandeli ebusweni be-calomel electrode ceramic sand core, ungasebenzisa iphepha le-emery noma wengeze amanzi etsheni lamafutha ukuze ulisuse ngobumnene.
⑺ Hlola njalo ukuqina kwe-calomel electrode, bese ukala amandla e-calomel electrode ehloliwe kanye nenye i-calomel electrode eqinile enoketshezi lwangaphakathi olufanayo ku-anhydrous noma kusampula yamanzi efanayo. Umehluko ongaba khona kufanele ube ngaphansi kuka-2mV, ngaphandle kwalokho i-calomel electrode entsha idinga ukushintshwa.
45. Yiziphi izinyathelo zokuphepha zokulinganisa izinga lokushisa?
Njengamanje, izindinganiso zikazwelonke zokuthuthwa kwendle azinayo imithetho ethile mayelana nokushisa kwamanzi, kodwa izinga lokushisa lamanzi libaluleke kakhulu ezinhlelweni ezijwayelekile zokwelashwa kwezinto eziphilayo futhi kufanele zinakwe kakhulu. Kokubili ukwelashwa kwe-aerobic kanye ne-anaerobic kuyadingeka ukuba kwenziwe ngaphakathi kwebanga elithile lokushisa. Uma lolu hlu seludlulile, izinga lokushisa liphezulu kakhulu noma liphansi kakhulu, okuzonciphisa ukusebenza kahle kokwelashwa futhi kubangele nokuhluleka kwalo lonke uhlelo. Ukunakwa ngokukhethekile kufanele kukhokhwe ekuqaphelweni kwezinga lokushisa kwamanzi angenayo esistimu yokwelapha. Uma izinga lokushisa lamanzi angenayo litholakala, kufanele sinake kakhulu izinguquko ekushiseni kwamanzi kumadivayisi wokwelapha alandelayo. Uma zingaphakathi kwebanga elibekezelelekayo, zinganakwa. Uma kungenjalo, izinga lokushisa lamanzi angenayo kufanele lilungiswe.
I-GB 13195–91 icacisa izindlela ezithile zokukala izinga lokushisa kwamanzi kusetshenziswa amathemometha angaphezulu, amathemometha ajulile noma amathemometha aguquguqukayo. Ngaphansi kwezimo ezijwayelekile, lapho kukalwa izinga lokushisa lamanzi okwesikhashana esakhiweni ngasinye senqubo yesikhungo sokuhlanza amanzi angcolile esizeni, ithemometha yengilazi egcwele i-mercury ngokuvamile ingasetshenziswa ukuyikala. Uma i-thermometer idinga ukukhishwa emanzini ukuze ifundwe, isikhathi kusukela lapho i-thermometer ishiya amanzi kuya lapho ukufundwa kuqediwe akufanele sidlule imizuzwana engu-20. Ithemometha kufanele ibe nesikali esinembile okungenani esingu-0.1oC, futhi umthamo wokushisa kufanele ube mncane ngangokunokwenzeka ukuze kube lula ukufinyelela ukulingana. Idinga futhi ukulinganiswa njalo umnyango we-metrology nokuqinisekisa kusetshenziswa ithemometha enembayo.
Lapho ukala izinga lokushisa lamanzi okwesikhashana, i-probe ye-thermometer yengilazi noma enye impahla yokulinganisa izinga lokushisa kufanele icwiliswe emanzini ukuze ikalwe isikhathi esithile (imvamisa engaphezu kwemizuzu emi-5), bese ufunda idatha ngemva kokufinyelela ukulingana. Inani lokushisa ngokuvamile linembile ukuya ku-0.1oC. Izitshalo zokuhlanza amanzi angcolile ngokuvamile zifaka ithuluzi lokulinganisa izinga lokushisa eliku-inthanethi ekugcineni kwe-water inlet yethangi lokungenisa umoya, futhi ithemometha ngokuvamile isebenzisa i-thermistor ukukala izinga lokushisa lamanzi.
Isikhathi sokuthumela: Nov-02-2023
