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Zaštita materijala 1. 2018

 

Slavko Smiljanić1*, Gordana Ostojić2, Aleksandar Došić1

1Univerzite u Istočnom Sarajevu,Tehnološki fakultet Zvornik, Zvornik, Republika Srpska, 2Fabrika glinice „Alumina“ Zvornik, Karakaj, Zvornik, Republika Srpska

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:622.794.2/.3:537.242.082,72
doi: 10.5937/ZasMat1801007S


Zastita Materijala 59 (1)
7 –  20  (2018)

Ispitivanje uticaja tretmana i mineraloškog sastava na tačku nultog naelektrisanja crvenog mulja

Izvod

Crveni mulj predstavlja jalovinu koja zaostaje nakon prerade boksita u glinicu po Bayer-ovom postupku. Svi elementi prisutni u crvenom mulju se nalaze u formi različitih minerala. Ovi minerali ne egzistiraju kao individualne čestice, nego su povezani sa drugim mineralima u agregate koji predstavljaju čestice crvenog mulja. Površinsko naelektrisanje predstavalja svojstvo crvenog mulja, koje utiče na niz njegovih karakteristika. Površinsko naelektrisanje se može razmatrati preko tačke nultog naelektrisanja. U ovom radu određena je tačka nultog naelektrisanja originalnog crvenog mulja i pojedinih tretiranih uroraka. Primenjeni tretmani imali su različit uticaj na pomeranje PZC i pufer područja. Originalni uzorak crvenog mulja odlikovao se visokom vrednošću pHPZC (9,7±0,2). Delimično ispiranje nije uticalo na promenu PZC, što sugeriše na veliku količinu zaostale baze iz proseca luženja. Termički tretman crvenog mulja nije bitno uticao na promenu finalne pH vrednosti pri kojoj se uočava plato (pHPZC = 9,4-9,9), dok je kiselinski tretman imao izraženiji uticaj (pHPZC = 6,2-7,9). Vrednosti PZC za kiselinski tretirane uzorke dobijene u inertnom elektrolitu, bile su niže od onih dobijenih u destilovanoj vodi. Svi razmatrani uzorci imali su izražen puferski region u kojem su finalne pH vrednosti bile nezavisne od inicijalnih. Delimično ispiranje i termički tretman nisu značajnije uticali na promenu pufer područja, dok je kiselinski tretman izazivao suženje pufer oblasti sa povećanjem koncentracije kiseline. Za pomeranje PZC tretiranih muljeva najodgovornije su fazne promene koje nastaju pri tretmanu, neutralizacija zaostale baze i alkalnih anjona u rastvoru, te promena kristaličnosti i rastvorljivosti minerala u mulju. Pravilnim izborom tretmana može se uticati na naelektrisanje površine mulja.

Ključne reči: crveni mulj, tačka nultog naelktrisanja, mineraloški sastav, tretman, fazne transformacije, pufer područje.

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EXAMINATION OF THE INFLUENCE OF TREATMENTS AND MINERAL COMPOSITION ON THE POINT OF ZERO CHARGE OF RED MUD

Abstract

Red mud represents tailings which remains after the processing of bauxite into alumina by Bayer’s proceedings. All the elements are present in the red mud are found in the form of different minerals. These minerals do not exist as individual particles, but are associated with other minerals in aggregates which represent particles of red mud. Surface charge is an important property of the red mud, which affects a number of its characteristics. Surface charge can be considered through the zero charge point. In this paper, the point of zero charge of the original red mud and certain treated samples is determined. Incomplete washing, thermal and acid treatment were used as treatments. The applied treatments had a different effect on the movement of the PZC and buffer region. The red mud sample was distinguished by a high value of pHPZC (9.7 ± 0.2). Incomplete washing did not affect the change in PZC, while thoroughly rinsing caused a significant movement of PZC to a lower pH. This suggests to a large amount of residual base from the leaching process. Thermal treatment of red mud did not significantly affect the change in the final pH at which plateau was observed (pHPZC 9.4-9.9), while acid treatment had a more pronounced effect (pHPZC 6.2-7.9). PZC values for acid-treated samples obtained in an inert electrolyte were lower than those obtained in distilled water, at least for one pH unit. All the analysed samples had a pronounced buffer region in which the final pH values were independent of the initial ones. Partial rinsing and thermal treatment did not significantly affect the change in buffer region, while acid treatment caused the narrowing of the buffer region with increasing acid concentration, but the samples continued to retain significant neutralization capacity.

For the move of the PZC treated muds, major responsibility have phase changes that occur in the treatment, neutralization of the residual base and the anions in the solution, and changing the crystallinity and the solubility of minerlas in the mud. Applying the appropriate treatment can affect the change in the mineral composition and, consequently, the changes in the charge of the surface.

Keywords: red mud, point of zero charge, mineral composition, phase transformation, treatment, buffer region.

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Ratko Ivković1*, Lazar Kopanja2

1Univerzitet u Prištini, Fakultet tehničkih nauka, Departman za elektrotehničko i računarsko inženjerstvo, Kosovska Mitrovica, Srbija, 2Alfa BK Univerzitet, Fakultet informacionih tehnologija, Beograd, Srbija

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:620.183.4(n)
doi: 10.5937/ZasMat1801021I

Zastita Materijala 59 (1)
21 – 30  (2018)

Hibridni metod za detekciju ivica na TEM slikama nanočestica

Izvod

Opšta primena fundamentalnih delova digitalne obrade slike nalazi sve širu primenu u različitim oblastima nauke. Sa ubrzanim razvojem tehnologije mikroskopskih slikanja, potreba za robusnom segmentacijom nanočestica značajno se povećava. Zbog velike različitosti u broju i obliku nanočestica na TEM slikama većina postojećih metoda samo je sposobna da segmentira određene vrste nanočestica. Uzimajući u obzir karakteristike nanočestičnih materijala, ovaj rad daje predlog novog algoritma detekcije ivica. Kao ocena podobnosti predloženog algoritma u radu, analiza je izvršena kako kroz prostornu, tako i kroz amplitudsku rezoluciju digitalne slike. U cilju dodatne preciznosti rezultata, analiza je vršena kroz slike nanočestica različitog stepena uvećanja. Slike tog tipa daju i različit stepen šumova u digitalnoj slici, pa je krajnja analiza dala ocenu stepena otpornosti na predloženi algoritmi detekcije ivica na šumove koji se javljaju u slikama nanočestica. Svi dobijeni rezultati ukazuju na visok stepen korisnosti obrađenih TEM slika, kako u prostornom tako i u amplitudskom domenu.

Ključne reči: digitalna obrada slike, detekcija ivica, hibridni metod, TEM slike, nanočestice.

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HYBRID EDGE DETECTION METHOD ON TEM IMAGES OF NANOPARTICLES

General application of the fundamental part of digital image processing is widely used in various fields of science. With the rapid development of microscopic imaging technology, the need for the robust segmentation of nanoparticles increased significantly. Due to large differences in the number and form of nanoparticles in TEM images, most of the existing methods are only capable of segmenting certain types of nanoparticles. Taking into account the characteristics of nanoparticle materials, this paper gives some suggestions for a new edge detection algorithm. As an assessment of similarity of the proposed algorithm in the paper, the analysis was carried out both through the spatial and through the amplitude resolution of the digital image. With the aim of obtaining additional accurate results, the analysis was conducted through images of nanoparticles of different degrees of magnification. Images of this type provide different levels of noise in digital image, therefore the final analysis gave an assessment of the degree of resistance to the proposed edge detection algorithm for noise occurring in nanoparticle images. All the obtained results indicate a high degree of utility of the processed TEM images, both in spatial and amplitude domain.

Keywords: digital image processing, edge detection, hybrid method, TEM images, nanoparticles.

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Darko Manjenčić1*, Suzana Cakić2, Branka Pilić1, Vojislav Aleksić3, Jaroslava Budinski-Simendić1, Sanja Rackov1,Ivan Ristić1
1Univerzitet u Novom Sadu, Tehnološki fakultet, Novi Sad, 2Univerzitet u Nišu, Tehnološki fakultet Leskovac, Leskovac, Srbija, 3Univerzitet u Istočnom Sarajevu, Tehnološki fakultet, Zvornik, R. Srpska
Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:504.064:800.6
doi: 10.5937/ZasMat1704421V

Zastita Materijala 59 (1)
31 – 38  (2018)

 

Uticaj dodatka nanopunila na svojstva silikonskih materijala na osnovu različitih prekursora mreža

Izvod

Pri projektovanju sirovinskog sastava elastomera, veoma je bitno izvršiti takav izbor polaznih prekursora koji će nakon procesa umrežavanja dati materijal za specifične uslove eksploatacije. U toku procesa umrežavanja makromolekula, izborom vrste i količine komponenata dobijaju se materijali željene elastičnosti, mehaničkih i hemijskih karakteristika. Silikoni, odnosno, polisiloksani, su zasigurno jedna od najinteresantnijih klasa elastomernih materijala. Već decenijama imaju veliki značaj kako u akademskom, tako i u industrijskom proučavanju, te su polja, u kojima se pronalazi njihova primena mnogobrojna (elektronika, proizvodi za ličnu negu, strukturno inženjerstvo i tekstil, medicina i sportska oprema i dr.). Silikoni, zbog svojih izvanrednih svojstava, su predodređeni za biomedicinsku primenu jer su bioinertni, transparentni i imaju izuzetnu propustljivost kiseonika.  Međutim, ovi materijali se uglavnom odnose na dimetilsiloksan strukturu, koja je poznata po svojoj biokompatibilnosti. Odlična biokompatibilnost je, delom, zbog niske hemijske reaktivnosti, niske površinske energije i hidrofobnosti polidimetilsiloksana. Cilj ovog rada je bio da se odrede karakteristike regularnih mreža kao i da se ustanovi mogućnost umrežavanja linearnih višefunkcionalnih siloksana. Za sintezu su korišćeni vinil-funkcionalizovani siloksani kao i polisiloksani, uz dodatak nanopunila. Umrežavanje sistema na bazi polidimetildisiloksana kao i njihovih blendi izvođeno je na temperature od 80˚C u vakumu. Hemijska struktura dobijenih materijala je analizirana FTIR metodom, koja je potvrdila pretpostavljen mehanizam umrežavanja korišćenih silikonskih prekursora. Uticaj nanopunila na mehanička i termička svojstva dobijenih silikona je detaljno izučavan, pri čemu je prisutan jasan trend poboljšanja mehaničkih svojstava silikona sa dodatkom nanopunila. Uticaj nanopunila (silicijum(IV)oksida) na toplotna svojstva silikona je potvrđen na osnovu DSC rezultata. Iz ove grupe linearnih organofunkcionalnih siloksana, u poslednje vreme, difunkcionalni α, ω – organofunkcionalni siloksani su sve više u centru pažnje nauke i ekonomije, kao reaktivni reagensi za sintezu organskih polimera. Tri kooperativna uticaja, unutrašnja fleksibilnost, karakteristike lateralnog pakovanja individualnih makromolekula i prisustvo intermolekulskih privlačenja, predstavljaju veoma osetljiv sistem faktora koji se moraju posmatrati ukoliko se žele dobiti definisana svojstva. Na osnovu ovoga hemijskim dizajniranjem podešavana je struktura mreža i vremenski praćen stepen kritične konverzije umrežavajućih materijala.

Ključne reči: nanokompoziti, elastomeri, silikon, silicijum(IV)oksid.

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THE INFLUENCE OF NANOFILLER ON THE  PROPERTIES OF BIOCOMPATIBLE SILICONE BASED ON DIFFERENT NETWORK PRECURSORS 

Abstract

The choice of starting network precursors for elastomeric material preparation is highly important in order to obtain materials for specific application. During the cross linking of macromolecules, with the choice of type and quantity of the components, it is possible to fine tuning material flexibility, mechanical and chemical characteristics. Silicones, more precisly polysiloxanes, are for sure one of most interested class of elastomeric materials.  For decades silicones are under huge interest of academical and industrial researches so the fields of their potentially usages are broad (electronics, personal care products, structural engineering and textiles, medicine, sports equipment…). Silicones, because of their extraordinary properties are predestined for biomedical purposes because they are bioinert, transparent and they have excellent oxygen permeability. Great biocompatibility is partly because of its low chemical reactivity, low surface energy and hydrofobicity of polydimethylsiloxane. The purpose of this work was to determine branched structures and charachteristics of noanocomposite organofunctionals siloxanes.  For synthesis were used vinyl-functionalized siloxanes and also polysiloxanes with adding of nanofillers. Cross linking of materials based on polydemitylsiloxanes and this compound was performed on 80˚C in vacuum. The chemical structure of the obtained materials was confirmed on the basis of the FTIR analysis, which confirmed the assumed mechanism of crosslinking of used silicone precursors. The influence of nanofillers on the mechanical and thermal properties of the obtained silicon is studied in detail, wherein was present a clear trend of improvement of mechanical properties of the silicone with the addition of nanofillers.  Influence of nanofillers on the thermal properties of the silicone is confirmed based on DSC results. From this group of linear organic functional siloxanes, difunctional α and ω – siloxanes are more in focus of science and economy in recent times, as they are reactive agens for synthesis of organic polymers. Three cooperative influences are their inner flexibility, characteristic of lateral packing of individual macromolecules and presence of intermolecular attraction represent sensitive system of factors which have to be observed in order to acquire defined properties.

Keywords: nanocomposites, elastomers, silicones, silica.

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Leposava Filipović-Petrović* Dušan Stanojević, Mirjana Antonijević-Nikolić, Ljubica Mijić

Visoka medicinska i poslovno-tehnološka škola strukovnih studija, Šabac, Srbija

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:666.32.002.3-121(n):553.612
doi: 10.5937/ZasMat1801039F


Zastita Materijala 59 (1)
39 – 44  (2018)

Mineraloška, fizičko-hemijska i keramička svojstva gline Brezaci

IZVOD

Podrinjsko-kolubarski region sa aspekta nemetaličnih mineralnih sirovina, odlikuje se, kako brojnošću mineralnih vrsta tako i kvalitetom mineralnih sirovina, kao retko koji rudonosni region u užoj Srbiji. Industrijski najznačajnija do sada otkrivena ležišta su nalazišta opekarskih i keramičkih glina u tamnavskom basenu.

U ovom radu izneti su neki rezultati mineraloških, fizičko-hemijskih i keramičkih ispitivanja gline Brezaci-Donje Crniljevo. Na osnovu dobijenih eksperimentalnih rezultata može se zaključiti da glina Brezaci-Donje Crniljevo pripada grupi kaolinitno-ilitnih  glina sa primesama kvarca, feldspata i liskuna. Saznanja iz ovog rada ukazuju da ispitivana glina poseduje značajan potencijal kao sirovinska komponenta za dobijanje brojnih keramičkih proizvoda.

Ključne reči: gline, glineni minerali, mineraloški sastav, keramička svojstva.

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MINERALOGICAL, PHYSICO-CHEMICAL AND CERAMIC PROPERTIES OF BREZACI CLAY

Abstract

The Podrinje-Kolubara region, from the point of non-metallic mineral raw materials, is characterized not only by numerous mineral types, but the quality of mineral resources as well as, being one of few mineral regions in that part of Serbia. Deposits of clay and ceramic clay in the Tamnava basin have been industrially the most important deposits up to now.

This paper presents some results of mineralogical, physico-chemical and ceramical-technological analyses of ceramic clay Brezaci-Donje Crniljevo. Based on the obtained experimental results, it can be concluded that clay Brezaci-Donje Crniljevo belongs to the kaolinite-illite  clay with traces of quartz, feldspar and mica. The findings from this study indicate that the examined clay has significant potential as a material raw component for numerous ceramic products.

Keywords: clay, clay minerals, mineralogical composition, ceramic properties.

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Marina Kolundžić1, Jelena Radović1, Ana Tačić2, Vesna Nikolić2, Tatjana Kundaković1*
1University of Belgrade, Faculty of Pharmacy, Department of Pharmacognosy, Belgrade, Serbia, 2University of Niš, Faculty of Technology, Department of Organic and Technological Sciences, Leskovac, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:635.8:635.81.095.337
doi: 10.5937/ZasMat1801045K

Zastita Materijala 59 (1)
45 – 50  (2018)

Elemental composition and nutritional value of three edible mushrooms from Serbia

Abstract

Nutrition value, as well as macro- and microconstituents of three edible mushrooms (Pleurotus ostreatus, Lentinula edodes, Macrolepiota procera) collected in Serbia were tested. It has been determined that all three mushroom samples were low in energy, fat and carbohydrates, but rich in β-glucans content. The most abundant elements in these three mushrooms were essential marcroelements Ca, K and P, but also there is a significant amount of Li, Se and Zn. On the other hand, toxic elements, such as Pb, As and Cd were also detected in level higher than allowed.

Keywords: Pleurotus ostreatus, Lentinula edodes, Macrolepiota procera, nutrition value, elemental analysis.

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SASTAV MIKRO I MAKROELEMENATA I NUTRITIVNA VREDNOST U TRI JESTIVE PEČURKE IZ SRBIJE

Izvod

Nutritivna vrednost, kao i sadržaj makro- i mikroelemenata testirana je u uzorcima tri jestive pečurke, sakupljene u Srbiji (Pleurotus ostreatus, Lentinula edodes, Macrolepiota procera). Pokazano je da su sve tri gljive bile siromašne energijom, mastima i ugljenimhidratima, ali bogate β-glukanima. Najzastupljeniji elementi u sva tri uzorka bili su esencijalni makroelementi Ca, K i P, ali je takođe je detektovana značajna količina Li, Se i Zn. Sa druge strane, koncentracija toksičnih metala, Pb, As i Cd, bila je iznad dozvoljenih granica.

Ključne reči: Pleurotus ostreatus, Lentinula edodes, Macrolepiota procera, nutritivna vrednost, analiza hemijskih elemenata.

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Slađana B. Tanasković1*, Mirjana Antonijević-Nikolić2, Branka Dražić1

1University of Belgrade, Faculty of Pharmacy, Belgrade, Serbia, 2Higher Medical and Business-technological School of Professional Studies, Šabac, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:631.81.095.338:546.73
doi: 10.5937/ZasMat1801051T

Zastita Materijala 59 (1)
51 – 55  (2018)

New mixed ligand Co(II) complexes- synthesis, characterization and antimicrobial activity

Abstract

A new complexes with general formula [Co2(X)2tpmc](BF4)2·Y (X= F, Y=CH3CN; X= Br, Y= H2O; tpmc = N,N’,N”,N”’- tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane), were isolated and their composition, some of physical and chemical properties and their tentative geometries were evaluated based on: elemental analysis (C, H, N), conductometric and magnetic measurements, spectroscopic data (UV/Vis, IR) respectively. Then, we compared synthesized complexes with early described chloro analogous. Both complexes are binuclear with proposed chair conformation of macrocycle. Complex compounds were also preliminary assayed in vitro toward some Gram (+) and Gram (-) bacteria, fungi and mould together with the starting material for the synthesis (ligands, simple salts and solvents) as test substances. In some cases certain antimicrobial activity of the complexes was detected. Minimal inhibitory concentration suppressing the visible growth of bacteria was determined.  Both investigated complexes showed a moderate activity against strains of bacteria and were inactive against the tested fungi and mould. Under the same conditions and applied the same concentration of the control group did not show activity.

Keywords: antimicrobial activity, Co(II) complexes, pendant octaazamacrocycle.

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NOVI MEŠOVITO-LIGANDNI KOMPLEKSI Co (II)- SINTEZA, KARAKTERIZACIJA I ANTIMIKROBNA AKTIVNOST

Izvod

Pripremlljena  su  dva nova kompleksa opšte formule [Co2(X)2tpmc](BF4)2·Y (X= F, Y=CH3CN; X= Br, Y= H2O; tpmc = N,N’,N”,N”’- tetrakis(2-piridilmetil)-1,4,8,11-tetraazaciklotetradekan), čiji su sastav, neke fizičke i hemijske osobine kao i približne geometrije  određene na osnovu  elementalne analize (C, H, N), konduktometrijskih i magnetnih merenja i spektroskopskih podataka (UV/Vis, IR). Podaci su upoređeni sa ranije sintetisanim i opisanim hloro analogom. Oba nova kompleksa Co(II) su dinuklearna sa pretpostavljenom egzo koordinacijom makrocikla u konformaciji  stolice. Kompleksi su preliminarno testirani na neke Gram (+), Gram (-) bakterije,  plesni i kvasce zajedno sa startnim supstancama za sintezu (ligandima, prostim solima i rastvaračima) koje su služile kao test supstance. Određivana je minimalna inhibitorna koncentracija koja sprečava rast bakterija. U nekim slučajevima je nađena izvesna antimikrobna  aktivnost. Oba kompleksa su pokazala aktivnost prema bakterijama ali su inaktivni prema gljivicama i kvascima dok je pod istim uslovima i istim primenjenim koncentracijama  kontrolna grupa bila neaktivna.

Ključne reči: antimikrobna aktivnost, Co(II) kompleksi, pendantni oktaazamakrocikli.

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Nevenka Mijatović1*, Lato Pezo2, Anja Terzić1, Snežana Šerbula3, Renata Kovačević4

1University of Belgrade, Institute for Testing of Materials IMS, Belgrade, Serbia, 2Institute of General and Physical Chemistry, Belgrade, Serbia, 3 University of Belgrade, Technical Faculty in Bor, Bor, Serbia, 4Mining and Metallurgy Institute Bor, Bor, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:613.95/.99
doi: 10.5937/ZasMat1801057M

Zastita Materijala 59 (1)
56 – 66  (2018)

The biometrics techniques for the assessment of the degree of adoption of toxic and essential elements

Abstract

The focus of this study is on the biometric classification of plants, plant organs, sampling sites and sampling time, in terms of toxic (As, Cd, Hg and Pb) and essential elements (Cu and Zn) monitoring, and possible the application in phyto-remediation. The degree of adoption of elements depends on the plant species and its morphological and physiological properties, therefore the adoption of toxic and essential elements in three plant species (coltsfoot, dandelion and nettles) was investigated. Vegetation experiments were carried out in the coastal region of river Kriveljska, Serbia. Principal component analysis and analysis of variance were used for assessing the effect of plant types, plant organs (root, shoot and leaves), and sampling sites and sampling time (April, May, June) on toxic and essential elements uptake. Obtained results showed that a difference in toxic and essential elements uptake depends mostly upon the cultivar and the plant organ types. Biometric techniques provided a good opportunity for a better understanding the behaviour of plants and obtaining much more useful information from the original data.

Keywords: coltsfoot, dandelion, nettles,toxic elements, essential elements, biometrics monitoring.

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BIOMETRIJSKE TEHNIKE ZA OCENU STEPENA USVAJANJA TOKSIČNIH I ESENCIJALNIH ELEMENATA

Izvod

Fokus ove studije je na biometrijsku klasifikaciju biljaka, biljnih organa, lokaliteta i vremena uzorkovanja, u smislu praćenja stepena usvajanja toksičanih (As, Cd, Hg i Pb) i esencijalnih elemenata (Cu i Zn), i mogućnost primene u fito-remedijaciji. Stepen usvajanja elemenata zavisi od biljne vrste i njenih morfoloških i fizioloških osobina. Usvajanje toksičnih i esencijalnih elemenata u ovom radu je praćeno kod tri vrste biljaka (podbel, maslačak i kopriva). Uzorkovanje biljaka i zemljišta je vršeno u priobalnom regionu Kriveljske reke, Srbija. Analiza glavnih komponenti i analiza varijanse su korišćene za procenu efekasnosti usvajanja toksičnih i esencijalnih elemenata kod pomenutih biljnih vrsta, biljnih organa (korena, stabla i lišća), lokaliteta i vremena uzorkovanja (april, maj, jun). Dobijeni rezultati su pokazali da je razlika u usvajanju toksičnih i esencijalnih elemenata najviše zavisi od sorte i tipova biljnih organa. Biometrijske tehnike pružaju mogućnost za bolje razumevanje ponašanja biljaka i dobijanja mnogo korisnih informacija iz izvornih podataka.

Ključne reči: podbel, maslačak, kopriva, toksični elementi, esencijalni elementi, biometrijski monitoring.

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Milan Milivojević*, Biljana Pejić, Marija Vukčević, Mirjana Kostić

Univerzitet u Beogradu, Tehnološko-metalurški fakultet, Beograd, Srbija

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:66.067.8.081.3:546.47.815
doi: 10.5937/ZasMat1801069M

Zastita Materijala 59 (1)
67 – 76  (2018)

Novi biosorbent na bazi vlakna konoplje (Cannabis sativa) i Ca-alginata za uklanjanje jona olova i cinka

Izvod

U ovom radu ispitana je mogućnost primene novog biosorbenta, na bazi kratkih hemijski modifikovanih vlakana konoplje impregniranih alginatnim gelom, za adsorpciju jona olova(II) i cinka(II). Biosorbent na bazi alginata i alkalno tretiranih vlakana konoplje okarakterisan je sa aspekta strukture i morfologije primenom skenirajuće elektronske mikroskopije (SEM) i prirode funkcionalnih grupa korišćenjem infracrvene spektroskopije sa Furijeovim transformacijama (FT-IR). Adsorpcione karakteristike ovog kompozita, ispitivane su praćenjem kinetike adsorpcije jona olova i cinka, i upoređene su sa adsorpcionim karakteristikama alkalno tretiranih vlakana konoplje. Podaci dobijeni tokom adsorpcije, testirani su korišćenjem Lagergrenovog modela pseudo-prvog reda i pseudo-drugog reda, kao i modela intračestične difuzije. Slaganje modelnih i eksperimentalnih podataka pokazuje da adsorpcioni proces prati kinetiku pseudo-drugog reda, što upućuje na zaključak da tokom adsorpcije jona olova i cinka na površini ispitivanih uzoraka konoplje i kompozita alginat-konoplja, preovladava mehanizam hemisorpcije. Ova zapažanja su potvrđena i rezultatima FT-IR analize, koji pokazuju da se joni teških metala vezuju na karboksilnim, i delimično hidroksilnim grupama prisutnim na površini ispitivanog biokompozita. Na osnovu dobijenih rezultata zaključuje se da se novi biosorbent može uspešno koristiti, kao jeftin i efikasan adsorbent za uklanjanje jona teških metala iz vode.

Ključne reči: adsorpcija, alginat, vlakna konoplje, biokompozit, Pb(II),  Zn(II).

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HEMP FIBERS  (Cannabis Sativa)  IMPREGNATED BY Ca-ALGINATE GEL AS A NOVEL BIOSORBENT FOR THE REMOVAL OF  Pb(II) and Zn(II) IONS

Abstract

In this paper the possibility of implementing the new biosorbent composed of chemically modified short hemp fibers impregnated with alginate gel for adsorption of lead(II) and zinc (II) ions was investigated. Waste hemp fibers, alkaly treated, were used as an alginate carrier in order to improve the mechanical stability of alginate. Morphological characteristics of obtained alginate-hemp composite were investigated by scanning electron microscopy (SEM), while the Fourier transform infrared spectroscopy (FT-IR) was used for examination of surface chemistry. Alginate immobilization on the hemp fibers surface leads to the morphological changes, by decreasing the roughness of short hemp fibers. FT-IR analysis showed that surface chemistry was changed after alginate immobilization, primarily by increasing the amount of carboxyl groups. The presence of surface groups characteristic for hemp fibers, on the surface of biocomposite, indicate that the surface of hemp fibers is not completely covered by alginate. Adsorption characteristics of alginate-hemp biosorbent were examined through the adsorption of lead and zinc ions, and compared with the adsorption characteristics of alkali treated hemp fibers. Biosorption of lead and zinc ions onto both hemp fibers and alginate-hemp composite, represent fast process since 80 % of initial ions amount were adsorbed in first five minutes. Obtained adsorption data were analyzed by Lagergren pseudo-first and pseudo-second order kinetic models, as well as intraparticle diffusion model. It was found that biosorption of lead and zinc ions on alkali treated hemp fibers and alginate-hemp composite obey the pseudo-second order adsorption kinetics, indicating that adsorption/binding of ions is mediated by chemical forces rather than physical forces of attraction. This observation was confirmed by results of FT-IR analysis of alginate composite surface before and after ions adsorption. It was found that lead and zinc ions predominantly bind on carboxyl and hydroxyl groups through the ion-exchange and surface complexation. New biosorbent demonstrated effective removal of the ions, with the possibility of further process optimization in order to increase the adsorption capacity and rate of metal ions removal.

Keywords: biosorption, alginate, hemp fibers, biocomposite, Pb(II),  Zn(II).

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Nemanja Tošković1, Danijela Rajić1,Ljubica Vasiljević1, Dragan Tošković1*, Miloš Rajković2

1University of East Sarajevo, Faculty of Technology, Zvornik, Bosnia and Herzegovina, 2University in Belgrade, Faculty of Agriculture, Zemun, Belgrade, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC: 543.4/.5:546.57.59
doi: 10.5937/ZasMat1801079T

Zastita Materijala 59 (1)
77 – 81  (2018)

Determination of Au and Ag from iron ores combining FA and ICP/AES methods

Abstract

In this paper, the combination of FA (Flame Analysis of Noble Metals – Cupellation) and ICP/AES (Atomic Emission Spectrometry with Induction Coupled Plasma) methods for determination of Au and Ag in geological samples of iron ore-magnetite was presented.Au and Ag were concentrated with Pb from PbO after desulphurisation and melting process (Pb2+→Pb). Regulus (Pb with noble metals) is then cupellated. The resulting bead-pril after cupellation was dissolved in HNO3 and then in HCl (imperial water: 2HNO3 and 6HCl). After the preparation of standard solutions and a blank test, the ICP/AES recording is performed. The obtained results werecompared with those obtained by the classical method of cupellation. The advantages of ICP/AES are excellent detection limits and linear dynamic range as well as a stable and repeating signal which is particularly important for samples of iron tested due to the low content of noble metals.

Keywords: geological samples, FA, ICP / AES,noble metals.

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ODREĐIVANJE Au I Ag IZ RUDE GVOŽĐA KOMBINOVANJEM FA I ICP/AES METODA

Izvod

U ovom radu je prikazana kombinacija FA (plamena analiza plemenitih metala-kupelacija) i ICP/AES (atomska emisiona spektrometrija sa indukovanom kuplovanom plazmom) metoda za određivanje Au i Ag u geološkim uzorcima rude gvožđa-magnetit. Au i Agse koncentišu sa Pb iz PbOnakon procesa odsumporavanja i topljenja (Pb2+→Pb).Regulus (Pb sa Au i Ag)se kupelira. Dobijena perla-pril nakon kupelacije se rastvara u HNO3 a zatim u HCl(carska voda 2HNO3 : 6HCl). Nakon pripreme standardnih rastvora i blank probe vrši se snimanje na ICP/AES. Dobijeni rezultati su poređeni sa rezultatima dobijenim klasičnom metodom kupelacije. Prednosti ICP/AES su odlične granice detekcije i linearni dinamički opseg kao i stabilan i ponovljiv signal što je posebno bitno za uzorke ispitivane rude gvožđa zbog malog sadržaja plemenitih metala.

Ključne riječi: geološki uzorci, FA, ICP/AES, plemeniti metali

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Dragana Tomašević Pilipović1*, Aleksandar Došić2, Đurđa Kerkez1,Nataša Slijepčević1, Božo Dalmacija1, Miladin Gligorić2, Milena Bečelić-Tomin1

1Univerzitet u Novom Sadu, Prirodno-matematički fakultet, Departman za hemiju, biohemiju i zaštitu životne sredine,
Novi Sad, Srbija, 2Univerzitet u Istočnom Sarajevu, Tehnološki fakultet, Zvornik, Republika Srpska, Bosna i Hercegovina

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:622.794.2/.4
doi: 10.5937/ZasMat1801084T

Zastita Materijala 59 (1)
82 – 91  (2018)

Karakterizacija otpadnog mulja sa jalovišta tretiranog letećim pepelom i crvenim muljem u cilju solidifikacije/stabilizacije

Izvod

U radu je prikazana problematika otpadnog mulja sa jalovišta rudnika ”Sase” zagađenog toksičnim metalima, kao i tretman jalovine postupkom solidifikacije/stabilizacije (S/S). Kao imobilizacioni agensi korišćeni su leteći pepeo i crveni mulj koji predstavljaju sporedan industrijski otpad, te je njihovom primenom u ovom tretmanu ujedno ostvarena imobilizacija dve vrste otpada.  Tokom poslednjih nekoliko godina termin “zeleni” koncept u upravljanju opasnim otpadom dobija sve veći značaj, i odnosi se na procese i aktivnosti koje imaju mali ili zanemarljiv uticaj na životnu sredinu. Za procenu potencijalne mobilnosti metala u netretiranim i tretiranim uzorcima jalovine korišćena je modifikovana sekvencijalna ekstrakcija. Rezultati sekvencijalne ekstrakcione procedure S/S smeša ukazali su na to da su metali u smešama skoro potpuno imobilisani i ne predstavljaju rizik za životnu sredinu, naročito u smeši jalovine sa crvenim muljem. Glavni cilj ovog rada je karakterizacija tretiranih uzoraka primenom skenirajuće elektronske mikroskopije sa elementarnom analizom (SEM-EDS) i rendgenske difrakcije (XRD), koje su pružile dokaze o formiranju kompaktnog matriksa i pozolaničkih produkata.  Dobijeni rezultati pokazuju da je crveni mulj efikasniji za imobilizaciji metala u odnosu na leteći pepeo.

Ključne riječi: jalovina, crveni mulj, leteći pepeo, SEM-EDS, XRD, modifikovana sekvencijalna ekstrakcija.

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CHARACTERIZATION OF SLUDGE FROM THE TAILINGS WITH FLY ASH AND RED MUD AFTER THE PROCESS OF SOLIDIFICATION/STABILIZATION

Abstract

The paper presents the problem of waste sludge from mine tailing ”Sasa” contaminated with toxic metals, as well as the treatment of process solidification/stabilization. As a stabilizing agent fly ash and red mud were used.  Fly ash and red mud represent a secondary industrial waste, and its application in the treatment immobilized two types of waste. Over the past few years, the term “green” concept of hazardous waste management has gained increasing importance, and refers to processes and activities that have a small or negligible impact on the environment. A modified sequential extraction was used to estimate potential metal mobility in untreated and treated mine tailings samples. The results of the sequential extraction procedure of the S/S mixture indicate that the metals in the mixtures are almost completely immobilized and do not pose a risk to the environment, especially in the red sludge mixture. The main objective of this paper is to characterize the treated samples using a scanning electron microscopy with elemental analysis (SEM-EDS) and X-ray diffraction (XRD). This  analysis  confirmed  the formation of compact matrices and pozzolanic products. Obtained results indicated that red mud and fly ash effectively perform the immobilization of metals in the mine tailing.

Keywords: mine tailing, red mud, fly ash, SEM-EDS, XRD

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Bore V. Jegdić1*, Biljana M. Bobić1, Bojana M. Radojković2, Behar Alić3

1Univerzitet u Beogradu, Institut za hemiju tehnologiju i metalurgiju, Beograd, Srbija, 2Univerzitet u Beogradu, Inovacioni centar Mašinskog fakulteta, Beograd, Srbija, 3Metalurški Institut, “Kemal Kapetanović”, Zenica, Bosna i Hercegovina

Naučni rad
ISSN 0351-9465, E-ISSN 2466-2585
UDC:620.192.6:669.15-196.56
doi: 10.5937/ZasMat1801094J

Zastita Materijala 59 (1)
92 – 99  (2018)

Formiranje i rast pitova na austenitnom nerđajućem čeliku X5CrNi18-10 u prisustvu hlorida i sulfata

Izvod

Primenom potenciodinamičke metode ispitana je otpornost nerđajućeg čelika X5CrNi18-10 na piting koroziju, u rastvoru koji sadrži hloride i sulfate. Dobijeni rezultati pokazuju da je nerđajući čelik u značajnoj meri otporan prema formiranju pitova, ali postoji sklonost prema rastu pitova i koroziji u zazorima. Pitovi formirani na korozionom potencijalu nastavljaju stabilno da rastu. Izvršena je statistička analiza rezultata dobijenih pri ispitivanju piting korozije. Pokazano je da će se sa verovatnoćom od 95 % vrednosti pokazatelja otpornosti nerđajućeg čelika prema formiranju pitova (potencijal pitinga Epit, potencijal metastabilnog pitinga Empit i razlika Epit–Ekor) nalaziti u granicama od nekoliko procenata. Vrednosti pokazatelja otpornosti nerđajućeg čelika prema rastu pitova (količina naelektrisanja potrebna za rast pitova q, zaštitni potencijal Eprot i razlika Epit–Eprot) će se nalaziti u širim granicama. Pored navedenog, analiziran je izgled pitova na površini nerđajućeg čelika, kao i izgled dna pitova. Pokazano je da struktura ispitivanog nerđajućeg čelika nije senzibilizovana prema piting i interkristalnoj koroziji, odnosno da nerđajući čelik nije bio prethodno termički tretiran.

Ključne reči: nerđajući čelici, piting korozija, potenciodinamička metoda, statistička analiza.

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FORMATION AND GROWTH OF PITS ON X5CrNi18-10 AUSTENITIC STAINLESS STEEL IN PRESENCE OF CHLORIDES AND SULPHATES

Abstract

The resistance of X5CrNi18-10 stainless steel to pitting corrosion in a solution containing chlorides and sulphates was tested using the potentiodynamic polarization method. The obtained results show that the stainless steel is significantly resistant to pit formation, but it is susceptible to pit growth and crevice corrosion. Pits formed at the corrosion potential grow continuously. Statistical analysis of the results obtained during pitting corrosion testing was performed. It can be assumed with a probability of 95% that values of indicators of resistance to pit formation (the pitting potential Epit, the metastable pitting potential Empit and the difference Epit-Ekor) will be within the range of several percents. Values of indicators of resistance to pit growth (the amount of charge required for the pit growth q, the protective potential Eprot and the difference Epit-Eprot) will be within the broader range. In addition, the appearance of pits on the surface of the stainless steel, as well as the appearance of the pits bottom, were analyzed. It was shown that the structure of the stainless steel tested was not sensitized to pitting and intergranular corrosion, which means that the stainless steel was not previously thermally treated.

Keywords: stainless steels, pitting corrosion, potentiodynamic polarization method, statistical analysis.

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Zoran Janjušević, Vladislav Matković, Mladen Bugarčić*, Miroslav Sokić, Branislav Marković, Vaso Manojlović, Aleksandra Patarić

Institute for Technology of Nuclear and Other Mineral Raw Materials, Belgrade, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:669.283’17
doi: 10.5937/ZasMat1801102J


Zastita Materijala 59 (1)
100 – 107  (2018)

Molybdenum recovery as alloying agent from waste molybdenum solution

Abstract

The present work reports the commercialization of a recycling process of spent acid from filament tungsten wire plant to recover molybdenum (VI)-oxide and further utilizing this product for alloying cast iron. First part of the process consists of ammonia gas neutralization of spent acid containing molybdenum, crystallization and filtration of ammonium molybdate, drying and roasting to produce a commercial grade molybdic-trioxide powder (molybdenum mass fraction 59.2 mas%). Second part of the process consists of grey cast alloying with MoO3 in inducing furnace. Final product was hardened iron alloy with high yield of molybdenum recovery (up to 86 %).

Keywords: spent acid, ammonia neutralization, molybdenum-trioxide, alloying, cast iron.

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VALORIZACIJA MOLIBDENA IZ OTPADNOG MOLIBDENSKOG RASTVORA ZA LEGIRANJE SIVOG LIVA

Izvod

U istraživačkom radu opisan je komercializovan reciklažni proces prerade otpadnog rastvora iz postrojenja za proizvodnju sijaličnih vlakana od volframa radi izdvajanja molibden (VI)-oksida i njegovom daljem iskorišćavanju kao legirajućeg agensa sivog liva. U prvom delu izvršena je neutralizacija utrošene kiseline, koja u sebi sadrži izvesne količine molibdena, uz pomoć rastvora amonijaka, a potom kristalizacija i filtracija amonijum-molibdata, njegovo sušenje i prženje u cilju dobijanja praha molibdentrioksida tehničke čistoće (maseni udeo molibdena 59,2 mas%). U drugom delu izvršeno je legiranje sivog liva uz pomoć MoO3 u indukcionoj peći. Finalni proizvod je legura železa sa povećanom tvrdoćom uz postignut visok stepen usvajanja molibdena u leguri (čak do 86%).

Ključne reči: otpadni rastvor, neutralizacija amonijakom, molibdentrioksid, legiranje, sivi liv.

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Sahar Zolfaghari1, Amin Rabiei Baboukani1*, Ali Ashrafi2, Ahmad Saatchi3

1Islamic Azad University, Advanced Materials Research Center, Materials Engineering Department, Najafabad Branch, Najafabad, Iran, 2Isfahan University of Technology, Department of Materials Engineering, Isfahan, Iran, 3University of Wisconsin, Department of Materials Science and Engineering, Madison, USA.

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:620.197.3
doi: 10.5937/ZasMat1801110Z

Zastita Materijala 59 (1)
108 – 116  (2018)

Investigation the effects of Na2MoO4 as an inhibitor on electrochemical corrosion behavior of 316L stainless steel in LiBr solution

Abstract

The effect of sodium molybdate (Na2MoO4) as an inhibitor at various concentrations of 50, 100 and 200ppm on the electrochemical corrosion behavior of 316L stainless steel in LiBr solution at 60°C was studied by polarization curves, electrochemical impedance spectroscopy (EIS) methods and electron microscopy. Polarization curves indicate that Na2MoO4 acts as mixed-type inhibitor. The corrosion resistance of 316L stainless steel samples increases with the inhibitor concentration up to 200ppm. By increasing the inhibitor concentration from 50ppm to 200ppm, corrosion current density decreases. These results were confirmed by further analysis using a scanning electron microscope.

Keywords: sodium molybdate, corrosion, 316L stainless steel, Lithium bromide.

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ISPITIVANJE  EFEKATA Na2MoO4 KAO INHIBITORA NA ELEKTROHEMIJSKO KOROZIONO PONAŠANJE NERĐAJUĆEG ČELIKA 316L U RASTVORU LiBr

Izvod

Uticaj natrijum-molibdata (Na2MoO4) kao inhibitora pri njegovim različitim koncentracijama 50, 100 i 200 ppm na elektrohemijsko korozijsko ponašanje nerđajućeg čelika 316L u LiBr rastvoru na 60°C ispitani su polarizacionim krivinama, metodama elektrohemijske impedansne spektroskopije (EIS) i elektronske mikroskopije. Otpornost na koroziju uzorka nerđajućeg čelika 316L povećava se sa koncentracijom inhibitora do 200ppm. Povećanjem koncentracije inhibitora od 50ppm do 200ppm smanjuje se gustina korozivne struje. Ovi rezultati su potvrđeni daljom analizom koristeći skenirajući elektronski mikroskop.

Ključne reči: natrijum molibdat, korozija, nerđajući čelik 316L, litijum bromid.

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Nataša V. Valentić1 Jelena M. Lađarević1, Bojan Đ. Božić2, Dušan Ž. Mijin1*, Gordana S. Ušćumlić1

1University of Belgrade, Faculty of Technology and Metallurgy, Belgrade, Serbia, 2University of Belgrade, Faculty of Biology, Belgrade, Serbia

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:620.197.6
doi: 10.5937/ZasMat1801119V

Zastita Materijala 59 (1)
117 – 125  (2018)

 

Solvatochromism of 5-(4-substituted arylazo) -4-phenyl-6-methyl-3-cyano-2-pyridones

Abstract

Eight 5-(4-substituted arylazo)-4-phenyl-6-methyl-3-cyano-2-pyridones were synthesized by reaction of benzoylacetone and arendiazonium salt, followed by condensation with cyanoacetamide. Absorption spectra of all azo pyridone dyes were recorded in twelve protic and aprotic solvents in the range of 200-600 nm. A simple Hammett equation was used to study the effect of the substituents on the absorption spectra of these azo dyes. The solute-solvent interactions were clarified on the basis of linear solvation energy relationships concept proposed by Kamlet and Taft. The results showed that the solvent effects on the absorption spectra of the investigated azo dyes were very complex and strongly dependent on the nature of the substituents on the phenylazo group.

Keywords: Arylazo pyridone dyes, solvent effects, substituent effects, absorption spectra.

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SOLVATOHROMIZAM   5-(4-supstituisanih arilazo) -4-fenil-6-metil-3-cijano-2-piridona

Izvod

Osam 5-(4-supstituisanih arilazo)-4-fenil-6-metil-3-cijano-2-piridona je sintetizovano reakcijom benzoilacetona i arendiazonijumove soli, i kondenzacijom nastalog proizvoda sa cijano­acetamidom. Apsorpcioni spektri dobijenih arilazo piridonskih boja su snimljeni u dvanaest protičnih i aprotičnih rastvarača u opsegu od 200-600 nm. za proučavanje uticaja supstituenata na apsorpcione spektre ispitivanih azo boja korišćena je prosta Hametova jednačina. Interakcije rastvorak-rastvarač su razjašnjene na osnovu koncepta linearne korelacije energije solvatacije, koji su predložili Kamlet i Taft. Rezultati pokazuju da su efekti rastvarača na apsorpcione spektre istraženih azo boja veoma kompleksni i jako zavise od prirode supstituenata na fenilazo grupi.

Ključne reči: arilazo piridonske boje, uticaj rastvarača, uticaj supstituenata, apsorpcioni spektri.

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Abd El-Aziz S. Fouda1*, Adel H. Ali1,2

1El-Mansoura University, Faculty of science, Department of chemistry, El-Mansoura, Egypt, 2University of Taiz, Faculty of medical science, Department of medicinal laboratory, Taiz, Yemen

Scientific paper
ISSN 0351-9465, E-ISSN 2466-2585
UDC:620.193/.197
doi: 10.5937/ZasMat1801128F

Zastita Materijala 59 (1)
126 – 140  (2018)

Egy- dronate drug as promising corrosion inhibitor of C – steel in aqueous medium

Abstract

The effect of Egy – dronate as the corrosion inhibition of Carbon steel (CS) in 1 M HCl was studied by weight loss (WL), hydrogen evaluation (HE), Open circuit potential (EOCP), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS), electron frequency modulation (EFM) and surface examination of the specimens by atomic force microscopy (AFM), energy dispersion spectroscopy (EDS) and scanning electron microscopy (SEM). The results of the inhibition efficiency (IE %)   with increasing the concentration of inhibitor but decreases with raising the temperature. The adsorption of Egy – dronate on the C – steel surface obeys with Langmuir adsorption isotherm. The adsorption process is spontaneous, endothermic and physical adsorption.  . The results obtained from chemical and electrochemical techniques are a good agreement quality and gives the same behavior of the adsorption of Egy-dronate drug. All techniques have proved the thin film   formation adsorbed on the metal surface as a protective coated to prevent the dissolution metal in the corrosive medium, due to electrostatic attraction between unshared electrons of inhibitor molecules and the positive sites on the metal surface.

Keywords: corrosion inhibition, HCl, CS, adsorption, SEM, EDX, AFM.

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EGI-DRONAT KAO PERSPEKTIVNI INHIBITOR KOROZIJE UGLENIČNOG ČELIKA U VODENIM RASTVORIMA

Izvod

Uticaj Egi-dronata kao inhibitora korozije ugljeničnog čelika u 1M HCl proučavan je gubitkom težine, procenom vodonika, potencijalom otvorenog kola, potentiodinamičkom polarizacijom, elektrohemijskom spektroskopskom impedancijom, modulacijom elektronske frekvencije i ispitivanjem površina uzoraka atomskom mikroskopijom (AFM), spektroskopijom disperzije energije (EDS) i skenirajućom elektronskom mikroskopijom (SEM). Rezultati efikasnosti inhibicije (IE%) povećavaju se s povećanjem koncentracije inhibitora, ali se smanjuju sa podizanjem temperature. Adsorpcija Egi-dronata na ugljeničnoj – čeličnoj površini podudara se sa Langmuirovom adsorpcionom izotermom. Proces adsorpcije je spontana, endotermna i fizička adsorpcija. Polarizacijske krive pokazuju da je Egi-dronat mešoviti inhibitor koji ima tendenciju anodnom tipu. Rezultati dobijeni hemijskim i elektrohemijskim tehnikama su dobar kvalitet odogovora i daju isto ponašanje adsorpcije Egi-dronata. Sve tehnike su dokazale formiranje tankog filma na površini metala kao zaštitnu oblogu, kako bi se sprečio metal da se razlaže u korozivnom medijumu, zbog elektrostatičke privlačnosti između nerastvornih elektrona molekula inhibitora i pozitivnih mesta na površini metala.

Ključne reči: inhibicija korozije, HCl, ugljenični čelik, adsorpcija, SEM, EDKS, AFM.

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