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New type of anion-selective electrodes deposited on sliver

dc.contributor.advisorVučurović, Borislava
dc.contributor.otherNikolić, Branislav
dc.contributor.otherRekalić, Vladimir
dc.creatorJovanović, Vladislava M.
dc.date.accessioned2019-02-04T12:08:01Z
dc.date.available2019-02-04T12:08:01Z
dc.date.issued1988
dc.identifier.urihttp://eteze.bg.ac.rs/application/showtheses?thesesId=2760
dc.identifier.urihttps://fedorabg.bg.ac.rs/fedora/get/o:10920/bdef:Content/download
dc.identifier.urihttp://vbs.rs/scripts/cobiss?command=DISPLAY&base=70036&RID=3311631
dc.identifier.urihttp://nardus.mpn.gov.rs/123456789/5159
dc.identifier.urihttp://cer.ihtm.bg.ac.rs/handle/123456789/2547
dc.description.abstractPredmet teorijskog proučavanja i eksperimentalnog istraživanja ove disertacije bio je razrada novih postupaka dobijanja prevučenih jon-selektivnih elektroda (coated-on-wire ion-selective electrodes), proučavanje njihovih osobina u čistim rastvorima i ispitivanje mogućnosti njihove primene u realnim biološkim, farmaceutskim i ekološkim sistemima. Srebro-halogenidne elektrode dobijene su postupkom prevlačenja srebrne trake rastopom odgovarajućeg senzorskog jedinjenja, prethodno sintetizovanog taloženjem iz vodenih rastvora homogene smese halogenida i sulfida srebra. Potenciometrijskim i metalogtafskim ispitivanjem dobijenih prevlaka ustanovljeno je potpuno odsustvo poroznosti, dakle njihova izvanredna monolitnost. Osobine iz rastopa dobijenih srebro-halogenidnih elektroda slične su osobinama komercijalnih polikristalnih disk mambrana.Izrada nataložene srebro-sulfidne elektrode izlaganjem srebrne trake parama upravo stopljenog sublimisanog sumpora, postupak je koji traje svega nekoliko minuta. Monolitnost sulfidne prevlake utvrđena je ne samo metalografskim snimanjem već i njenom visokom otpornošću prema koroziji u koncentrovanim rastvorima cijanida koja mnogostruko prevazilazi otpornost komercijalnih cijanid-selektivnih elektroda. Razvijajući teorijske postavke eksperimentalnih istraživanja, zaključilo se da se izraz Sato-a namenjem izračunavanju vrednosti potencijala teško rastvornih sulfida, uz izmene, može uspešno primeniti i u slučaju ovih na srebro-nataloženih elektroda. Tako, vodeći računa o aktivitetima iste jonske vrste u čvrstoj fazi senzorske membrane kao i u tečnoj fazi rastvora u kome se selektivna elektroda nalazi, izračunati su strandardni potencijali ne samo halogenidnih i sulfidne elektrode u rastvorima odgovarajučih vrsti, već i standardni potencijali relevantnih elektroda u rastvorima cijanida. U ovom poslednjem slučaju od posebne važnosti bila je po prvi put sa naše strane primenjena, u literaturi poznata, ideja o izluživanju jona srebra iz defektne kristalne rešetke senzorske faze, za izračunavanje ovog potencijala. Izuzetno značajna, naročito sa teorijskog stanovišta, jeste i činjenica da je jedino nataložena srebro/srebro-sulfidna elektroda pokazala nagib od 120 mV po dekadi koncentracije cijanida, odstupajući na taj način za svega 2 mV od teorijske vrednosti u rastvorima ovih jona. Nagib komercijalnih cijanid-selektivnih elektroda odstupa inaće od teorijske vrednosti za više desetina mV. Od jednakog teorijskog i eksperimentalnog značaja jeste i činjenica da je ova elektroda u rastvorima cijanida ispoljila vrednost standarnog potencijala, određenog ekstrapolacijom, koja se za manje od 10 % razlikuje od teorijske vrednosti, izračunate po prvi put u ovoj disertaciji.sr
dc.description.abstractThe scope of the theoretical studies and experimental investigations of this thesis was development and examination of a new family of coated wire ion-selective electrodes. The properties of the electrodes obtained were studied in pure solutions and real biological, pharmaceutical and ecological systems. Silver halide electrodes were produced by coating the silver strip with the melt of the corresponding sensor compound prepared by previous precipitation from aqueous solutions of the homogeneous mixture of silver halide and silver sulphide. Potentiometric and metallographic examinations showed non-porosity and compactness of the coatings obtained. These electrodes have simmilar characteristics as polycrystalline disk membrane of the corresponding commercial ion-selective electrodes.Deposited silver-sulphide electrode was obtained by exposing the silver strip to the vapour of just melted sublimated sulphure. The compactness and non-porosity of the sulphide coating was proved both by metalographic examination and by high stabillity against corrosion in concentrated cyanide solution which was much higher than the stability of commercial cyanide-selective electrodes.Developing the theoretical assumptions of the experimental research, it was concluded that Sato's equation, obtained for the potentials of slight soluble sulphides could be applicable, with some modifications, also in the case of deposited-on-wire electrodes. Thus, taking into account the activities of the same ionic species present in the solid phase of the electrode membrane and in the licquid phase of the applied solution, the values of the standard potentials were calculated not only for deposited on silver-silver halide and silver-sulphide electrodes but also for the relevant electrodes in cyanide solutions. In the case of “cyanide“ potentials the idea of leaching of silver ions from the defect crystal lattice of the corresponding slight soluble compound, known from the literature, was of the great importance. Hence the E0 value for the cyanide response of the silver sulphide electrode is for the first time reported. The fact that only deposited-on-silver silver sulphide electrode exhibits the slope of 120 mV per concentration decade in cyanide solutions, deviating from the theoretical value only for 2 mV is of the great importance. The slope for commercial silver-sulphide polycrystalline disk membranes in cyanide solutions deviate from theoretical value for few tens of mV. The standard potential value in cyanide solutions for the deposited-on-silver/silver sulphide electrode found by extrapolation, differs from the theoretical one, for the first time estimated in this thesis, less than 10 %.en
dc.formatapplication/pdf
dc.languagesr
dc.publisherУниверзитет у Београду, Технолошко-металуршки факултетsr
dc.rightsopenAccess
dc.sourceУниверзитет у Београдуsr
dc.subjectsrebro/srebro halogenid selektivne elektrodesr
dc.subjectdeposited-on-silver silver halide electrodesen
dc.subjectsrebro/srebro sulfid selektivna elektrodasr
dc.subjectcijanid selektivna elektrodasr
dc.subjectstandni potencijal u rastvoru cijanidasr
dc.subjectdeposited-on-silver silver sulphide electrodeen
dc.subjectcyanide sensitive electrodeen
dc.subjectstandard potentials value in cyanide solutionsen
dc.titleNova vrsta na srebro nataloženih anjonskih selektivnih elektrodasr
dc.titleNew type of anion-selective electrodes deposited on sliveren
dc.typedoctoralThesisen
dc.rights.licenseBY-NC-ND
dcterms.abstractВучуровић, Борислава; Николић, Бранислав; Рекалић, Владимир; Јовановић, Владислава М.; Нова врста на сребро наталожених ањонских селективних електрода; Нова врста на сребро наталожених ањонских селективних електрода;
dc.identifier.fulltexthttp://cer.ihtm.bg.ac.rs/bitstream/id/8879/2544.pdf
dc.type.versionpublishedVersion


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