Zaštita Materijala 4. 2020

Contemporary laser techniques, general application in heritology and case of building in 7 Balkanska street, Belgrade

Abstract

It seems that the role of lasers in heritology and art has grown more and more since the end of the 20^th century; the early attempts of cleaning artistic objects, old monuments / artifacts during the times of Hedy Lamarr and the first unsuccessful nuclear tests as well as of thinking of holographic records. After the first series of circumstances linked to laser applications in restoration and conservation, it seems the coupling of words serendipity-zemblanity-bahramdipity has been activated. A long time has passed since the first works linked to the Porta della carte of the Palazzo Ducale (Doge’s Palace) in Venice (marble relief and ruby laser). Nowadays, this type of work can be treated as standardized and it is implemented in great number of countries [1, 2]. In the case of Florence Cathedral, the conservation of artworks was proposed by J. F. Fonatello, panels of the Giotto’s tower of the Florence Cathedral by Andrea Pisano.

The unique roles of quantum generators – lasers –  exist both in restoration and diagnostics. Besides that, the question of source existence – a source that provides completely new artistic impression with respect to its ideal characteristic of coherency – introduced new tools and techniques and could be (and was) implemented in many new processes and effects. New artistic directions were performed, where the source of the coherence became a part of a new artistic object, a hologram slide provokes the impression of the train entering the crowd, etc. [1–5] The laser role by using LIBS method in diagnostics in the case of the building in 7 Balkanska street, Belgrade, was presented in this paper.

Keywords: laser methods, LIBS, heritology, spectroscopy.

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Savremene laserske tehnike i opšta primena u heritologiji i slučaj zgrade u balkanskoj ulici 7, Beograd

Izvod

Čini se da je uloga lasera u heritologiji i umetnosti u stalnom porastu od kraja 20. veka; rani su pokušaji čišćenja umetničkih objekata, starih spomenika ili artefakata od vremena Hedi Lamar (Hedy Lamarr) i prvih neuspešnih nuklearnih testova, kao i razmišljanja o holografskim zapisima. Posle prve serije okolnosti vezanih za primene laserskih tehnika u restauraciji i konzervaciji, izgleda da je sprezanje reči serendipity, zemblanity i bahramdipity aktivirano. Prošlo je mnogo vremena otkad su obavljeni prvi radovi vezani za Porta della Carta Duždeve palate (Palazzo Ducale) u Veneciji – mermerni reljef i rubinski laser. Danas ovaj tip radova može da se tretira kao konvencionalan/standardan i primeni u nizu zemalja [1, 2]. U slučaju Katedrale u Firenci Fonatelo (J. F. Fonatello) je predložio konzervaciju umetničkih objekata, Pizanove (Andrea Pisano) panele na Đotovoj (Giotto) kuli Katedrale.

Jedinstvene uloge kvantnih generatora – lasera – postoje i u restauraciji i u dijagnostici. Osim toga, pitanje postojanja izvora – izvora koji nudi potpuno novi umetnički utisak u odnosu na idealne osobine koherencije – uvelo je nove alate i tehnike i moglo je da (i jeste) primeni mnogo novih procesa i efekata. Novi umetnički pravci su izvedeni, gde je izvor koherencije postao deo novog umetničkog objekta, hologram je izazvao utisak da voz ulazi u masu ljudi, itd. [1–5] Uloga lasera u dijagnostici i u svrhu konzervacije i neke primene na slučaj zgrade u Balkanskoj 7 u Beogradu je prikazana u ovom radu.

Ključne reči: laserske metode. LIBS, heritologija, spectroskopija.

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Electrochemical behavior for corrosion protection of mild steel (MS) in 1M HCl medium by using lidocaine drug as an inhibitor

Abstract

The impact of Lidocaine as a save corrosion inhibitor for mild steel (MS) in 1M HCl  by using weight loss (WL), Hydrogen evaluation (HE), open circuit potential (E_OCP), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and Electrochemical frequency modulation (EFM) techniques has been investigated. Weight loss studied at various temperatures between (25– 45^oC) but Hydrogen evaluation and electrochemical studies at room temperature. The effect of temperature on the inhibition of corrosion has been studied and the thermodynamic activationand adsorption parameters were calculated. The morphology of MS was examined by scanning electron microscope with energy dispersive X-ray spectroscopy (SEM–EDX) technology and atomic force microscopy (AFM). EIS  data indicate that in the presence of drug  the double layer capacitance was decreased and the charge transfer resistance increased. The adsorption of the Lidocaine on MS surface was found to obey Langmuir adsorption isotherm and elucidate the mechanism of corrosion inhibition. The Lidocaine drug acts as mixed type inhibitor. All surface examination confirms the formation thin film covered the surface of the metal and prevent the surface of the metal from corrosion.

Keywords: Adsorption; inhibition; electrochemical techniques; SEM; EDX; AFM.

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Elektrohemijsko ponašanje pri zaštiti od korozije mekog čelika (MS) u 1M HCl kiselini upotrebom leka lidokain kao inhibitora

Izvod

Lidokain, kao inhibitora korozije za zaštitu mekog čelik (MS) u 1M HCl,  proučavan je  ispitivanjem gubitka težine (VL), procene vodonika (HE), potencijala otvorenog kola (EOCP), potenciodinamičke polarizacije (PP), elektrohemijske impedansne spektroskopije (EIS) i elektrohemijske frekvencijske modulacije (EFM). Gubitak težine proučavan je na različitim temperaturama između (25 – 45⁰C) a procena vodonika i elektrohemijska ispitivanja na sobnoj temperaturi. Proučavan je uticaj temperature na inhibiciju korozije i izračunati termodinamički parametri aktivacije. Morfologija MS ispitivana je pomoću skenirajućeg elektronskog mikroskopa sa tehnologijom disperzivne rentgenske spektroskopije (SEM – EDKS) i atomskom mikroskopijom (AFM). Tehnika elektrohemijske impedance je pokazala da prisustvo leka lidokaina u rastvoru smanjuje dvoslojni kapacitet i povećava otpor prenosa naelektrisanja. Utvrđeno je da adsorpcija lidokaina na površini MS podleže izotermi Langmuir adsorpcije i razjašnjava mehanizam inhibicije korozije. Izračunati su parametri adsorpcije i utvrđeno je da lek lidokain deluje kao inhibitor mešovitog tipa. Sva površinska ispitivanja i analize potvrđuju formiranje tankog filma koji je prekrio površinu metala i sprečava koroziju površine metala.

Ključne reči: Adsorpcija; inhibicija; elektrohemijske tehnike; SEM; EDKS; AFM.

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Levels of some organic pollutants in water samples of Adriatic Sea. Case study: Hot-spot of Porto-Romano, Albania

Abstract

This paper presents concentrations of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in marine water samples of Porto-Romano area. Porto-Romano is situated in Adriatic Sea, near city of Durres, in central Albania. It was considered Hot-spot area because before 90’ there was located chemical plant for Lindane production. Landfill near Porto-Romano and elevated activity for industrial development of this area can be the main sources of water pollution in recent years. Water samples were taken in December 2018 and April 2019 in nine stations of Porto-Romano. Liquid-liquid extraction was used for isolate organic pollutants from water samples. Clean-up procedure for chlorinated pollutants was realized in a Florisil column. Qualitative and quantitative analyzes of pesticides and PCBs were performed in HP 6890 Series II, gas chromatograph equipped with μ-ECD detector. For separation of organochlorine pollutants was used Rtx-5 capillary column. Analyzes of PAH were realized in Varian 450 GC, gas chromatograph equipped with FID detector and VF-1ms capillary column.

The most frequent organic pollutants in water samples of Porto-Romano were found organochlorine pesticides because of ex-chemical plants impact in this area. Note, that Lindane and its isomers weren’t found in high concentration. PCB 28, volatile congener, was found in higher concentrations because of their atmospheric origin. Presence of PCB 138 show terrestrial origin of PCBs in this area. PAH were found in higher concentrations inside of hydrocarbon port. Their concentrations were due to industrial activity and ship transport in this area. Mismanagement of Lindane plant wastes, urban pollution and recent industrial activity are factors of continues pollution in Porto-Romano area. Presence of organic pollutants in water samples of Porto-Romano indicates that monitoring of this Hot-spot should be continuous.

Keywords: Organochlorine pesticides; PCBs; PAH; water pollution; GC/ECD/FID.

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Nivoi nekih organskih zagađivača u uzorcima vode jadranskog mora. Studija slučaja: žarište porto-romana, Albanija

Izvod

U ovom radu su predstavljene koncentracije organohlornih pesticida (OCP), polihlorisanih bifenila (PCB) i policikličnih aromatičnih ugljovodonika (PAH) u uzorcima morske vode područja Porto-Romano. Porto-Romano se nalazi na obali Jadranskog mora, u blizini grada Drača, u centralnoj Albaniji. Smatralo se zagađenim područjem, jer je pre devedesetih godina bilo smešteno hemijsko postrojenje za proizvodnju lindana. Deponija u blizini Porto-Romana i povećana aktivnost za industrijski razvoj ovog područja mogu biti glavni izvori zagađenja vode poslednjih godina. Uzorci vode uzeti su u decembru 2018. i aprilu 2019. godine u devet stanica Porto-Romano. Ekstrakcija tečnost-tečnost korišćena je za izolovanje organskih zagađivača iz uzoraka vode. Postupak čišćenja hlorisanih zagađivača realizovan je u koloni Florisil. Kvalitativne i kvantitativne analize pesticida i PCB-a izvršene su u gasnom hromatografu HP 6890 Series II, opremljenom m-ECD detektorom. Za odvajanje zagađivača organohlora korišćena je kapilarna kolona Rtk-5. Analize PAH realizovane su na Varian 450 GC, gasnom hromatografu opremljenom FID detektorom i kapilarnom kolonom VF-1ms.

Najčešći organski zagađivači u uzorcima vode Porto-Romana bili su organohlorni pesticidi, zbog uticaja bivših hemijskih postrojenja na ovom području. Uorci materije Lindane i njegovi izomeri nisu pronađeni u visokoj koncentraciji. PCB 28, isparljivi srodnik, pronađen je u višim koncentracijama zbog svog atmosferskog porekla. Prisustvo PCB 138 pokazuje zemaljsko poreklo PCB-a u ovom području. PAH je pronađen u višim koncentracijama unutar luke. Njihova koncentracija bila je usled industrijske aktivnosti i brodskog transporta na ovom području. Loše upravljanje biljnim otpadom Lindane, gradsko zagađenje i nedavne industrijske aktivnosti faktori su kontinuiranog zagađenja na području Porto-Romano. Prisustvo organskih zagađivača u uzorcima vode Porto-Romana ukazuje na to da bi nadgledanje ovog žarišta trebalo biti kontinuirano.

Ključne reči: Organohlorni pesticidi; PCB; PAH; zagađenje vode; GC / ECD / FID.

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Case study of extracting soil and land use maps to determine agricultural best management practices that can be applied to prevent erosion and fertile soil loss

Abstract

The Büyük Melen river in the Melen Basin meets Istanbul’s drinking water needs. Protecting the basin against nutrient pollution is vital in this regard as well. This study focuses on the best possible management practice (BMPs) in the Melen Basin to reduce the export of nutrients from the agricultural areas. A region comprising industrial, farming, and residential zones is the Melen basin. There is a forecast of global climate change in Turkey, and scientists and also governors must know which areas are no longer farming zones and which will be more appropriate for agriculture. Turkey’s territory is a high-risk desertification area. In Melen Basin, the soil type and land use properties have been determined and mapped using GIS and Soil and Water Assessment Tool (SWAT). Buffer BMP filter strips can be used effectively for nutrient protection that can be carried from residential areas and motorways by runoff. The region in the basin is steep, and its clay and sandy soil structures are ideal for parallel terraces, grade stabilization, strip, and contour cultivation. Unless the ground can not retain or store water, the soil can undergo sudden floods, causing an erosion of the soil’s productive surface layer. When we protect the land, this condition is reduced. The land type and land use mapping should be drawn up as soon as possible for the remaining Turkish basins by scientific methods. This research is intended to be an illustration for researches on other agricultural basins in Turkey and the world for this reason.

Keywords: Agricultural best management practices, erosion, land use, Melen Basin, nutrients, soil type.

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Studija slučaja uređenja i korišćenja zemljišta za određivanje načina upravljanja zemljištem koji se može primeniti u poljoprivrednoj praksi za sprečavanje erozije i gubitka plodnog zemljišta

Izvod

Reka Buiuk Melen u slivu Melen zadovoljava Istanbulske potrebe za pijaćom vodom. Zaštita bazena od zagađenja hranjivim sastojcima, takođe, je vitalna u ovom pogledu. Ova studija usredsređena je na najbolju moguću praksu upravljanja (BMP) u bazenu Melen kako bi se smanjio izvoz hranljivih sastojaka iz poljoprivrednih područja. Regija koja obuhvata industrijske, poljoprivredne i stambene zone je sliv Melena. U Turskoj postoji prognoza globalnih klimatskih promena, a naučnici i guverneri moraju znati koja područja više nisu poljoprivredne zone, a koja će biti prikladnija za poljoprivredu. Teritorija Turske je područje visokog rizika od dezertifikacije. U slivu Melen, vrsta zemljišta i svojstva korišćenja zemljišta utvrđeni su i mapirani pomoću GIS-a i Alata za procenu tla i vode (SWAT). Filterske trake puferskog BMP-a mogu se efikasno koristiti za zaštitu hranljivih sastojaka, koji se mogu odneti iz stambenih naselja i autoputeva. Regija u slivu je strma, a njene glinene i peskovite strukture tla idealne su za paralelne terase, stabilizaciju stepena, trakastu i konturnu kultivaciju. Ako tlo ne može da zadrži ili uskladišti vodu, zemljište može pretrpeti iznenadne poplave, što dovodi do erozije produktivnog površinskog sloja tla. Kada zaštitimo zemlju, ovo stanje se smanjuje. Kartiranje vrste zemljišta i upotrebe zemljišta trebalo bi da bude napravljeno što je pre moguće za preostale Turske basene naučnim metodama. Iz ovog razloga ovo istraživanje ima za cilj ilustraciju istraživanja na drugim poljoprivrednim basenima u Turskoj i svetu.

Ključne reči: Najbolje poljoprivredne prakse upravljanja, erozija, upotreba zemljišta, sliv Melen, hranljive materije, vrsta tla.

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Stress corrosion resistance of welded joints of low-alloy pipe steel produced by high frequency welding

Abstract

The paper presents the results of stress corrosion resistance studies of welded joints of low-alloy steel 17G1SU, obtained by high-frequency welding (HFW). The potentiometry method has established that the welded joint in the state after welding and after linear heat treatment is resistant to corrosion, because the potential difference between the weld and the base metal does not exceed (30-50) mV. According to the results of accelerated corrosion-mechanical tests in 3% NaCl under conditions of constant load  under different stress, it was found that the rate of uniform corrosion of both types of welded joints is almost the same as the base metal. Slightly higher corrosion rate of the welded junction after linear heat treatment correlates with the electrochemical data. In general, the welded joint, made according to the factory technology, has resistance to corrosion and mechanical destruction in a solution of 3% NaCl at the level of the base metal, in the absence of weld defects.

In the range of protective polarization potentials normalized by the standard of Ukraine, the ratio of the cathodic protection current to the diffusion current limit for the base metal and for the weld metal practically does not differ. It can be expected that under the conditions of cathodic protection, the predominant local flooding of the weld metal or the parent metal is not expected.

Keywords: low-carbon pipe steel 17G1S-U, welded joint, linear heat treatment, corrosion rate, stress corrosion resistance, potentiometry, method of polarization curves.

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Otpornost prema naponskoj koroziji zavarenih cevi od niskolegiranog čelika primenom visokofrekventnog indukcionog zavarivanja

Izvod

Predstavljeni su rezultati izučavanja otpornosti prema naponskoj koroziji zavarenih spojeva od niskolegiranog čelika 17G1SU, ostvarenih primenom visokofrekventnog zavarivanja (HFW). Potenciometrijska metoda je pokazala da je zavareni spoj, u stanju po zavarivanju i nakon neprekidnog žarenja (LHT), otporan na koroziju, što je protumačeno postojanjem potencijalne razlike između vara i osnovnog materijala koja nije prelazila 30-50mV. Prema rezultatima ubrzanog koroziono-mehaničkog ispitivanja u 3%NaCl pod dejstvom istog opterećenja a pri različitim naponima, nađeno je da je brzina uniformne korozije zavarenog spoja uglavnom ista kao u osnovnom materijalu. Nešto viša brzina korozije u zavarenom spoju a nakon neprekidnog žarenja je u korelaciji sa elektrohemijskim podacima. Uopšte, zavareni spoj urađen po fabričkoj tehnologiji i bez zavarivačkih grešaka, pokazao je otpornost prema koroziji i mehaničkom razaranju u 3% rastvoru NaCl na nivou osnovnog metala. U opsegu zaštitnog polarizacionog potencijala, propisanog od strane Ukrajinskog standarda, odnos katodne zaštitne struje prema graničnoj vrednosti struji difuzije, praktično se ne razlikuju između osnovnog metala i metala vara.  Pod uslovima katodne zaštite, neko značajnije lokalno strujanje između metala vara i osnovnog metala se ne očekuje.

Ključne reči: niskougljenični čelik za cevi 17G1SU, zavareni spoj, neprekidno žarenje, brzina korozije, otpornost prema naponskoj koroziji, potenciometrija. metoda polarizacionih krivih.

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Corrosion of the stainless steel 316Ti in 10% hydrochloric and sulfuric acid

Abstract

The corrosion of the austenitic stainless steel 316Ti is investigated in 10% hydrochloric and 10% sulfuric acid, by the means of linear polarization, electrochemical impedance spectroscopy, polarization, and weight loss measurements. It is concluded that 316Ti is unstable in 10% hydrochloric acid and passive in 10% sulfuric acid solution.

Keywords: Austenitic stainless steel; Titanium; Weight loss; Micrographs.

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Korozija nerđajućeg čelika 316ti u 10% hlorovodoničnoj i sumpornoj kiselini

Izvod

Korozija austenitnog nerđajućeg čelika 316Ti ispitivana je u 10% hlorovodoničnoj i 10% sumporne kiseline, pomoću linearne polarizacije, elektrohemijske impedanse spektroskopije, polarizacionih merenja i merenja gubitka težine. Zaključeno je da je 316Ti nestabilan u 10% hlorovodoničnoj kiselini i pasivan u rastvoru 10% sumporne kiseline.

Ključne reči: Austenitni nerđajući čelik, titan, gubitak mase, mikrografija.

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TiO₂ based nanomaterials and nanostructures for green convergent technologies and environmental protection

Abstract

Taking into account the importance of development of the advanced nanomaterials for the environmental protection, in this article the application of TiO₂ based nanomaterials and nanostructures in the fields of renewable energy, chemical and bio decontamination has been presented. The role of TiO₂ in formation of composite hybrid structures for solar energy harvesting has been explained, as well as the use of various antimicrobial TiO₂ based nanomaterials for photocatalytic degradation of pollutants. Special attention has been paid to structure and properties of TiO₂ nanotubes obtained by electrochemical anodization and their application in bio decontamination.

Keywords: TiO₂, convergent technologies, environmental protection, nanomaterials.

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Nanomaterijali i nanostrukture na bazi  TiO₂   za zelene konvergentne tehnologije i zaštitu prirodne okoline

Izvod

Imajući u vidu značaj razvoja naprednih nanomaterijala za zaštitu prirodne okoline, u ovome radu su prezentovane primene nanomaterijala i nanostruktura na bazi TiO₂ u oblastima obnovljivih izvora energije, hemijske i bio dekontaminacije. Objašnjena je uloga TiO₂ u formiranju kompozitnih hibridnih struktura za prikupljanje solarne energije, kao i primena različitih antimikrobnih materijala na bazi TiO₂ koji se koriste za fotokatalitičko uklanjanje polutanata. Naročita pažnja je posvećena strukturi i svojstvima titan dioksidnih nanotuba dobijenih primenom metode elektrohemijske anodizacije i njihova primena u bio dekontaminaciji.

Ključne reči: TiO₂, konvergentne tehnologije, zaštita prirodne okoline, nanomaterijali.

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