Pollution and risk assessment of the surface sediment of the Boka Kotorska Bay with heavy metals and radionuclides due to their bioavailability

Površinski morski sediment uzorkovan u decembru 2019. godine na dvanaest lokacija u Bokokotorskom zalivu, analiziran je primenom različitih instrumentalnih metoda u cilju postizanja hemijske, teksturalne i radiološke karakterizacije sedimenta. Određen je sadržaj deset oksida i dvadeset šest elemenata (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2, TiO2, i As, Ba, Br, Cl, Co, Cr, Cs, Cu, Ga, La, Mo, Nb, Ni, Pb, Rb, S, Sb, Se, Sn, Sr, Th, U, V, Y, Zn, Zr), dodatnih teških metala (Cd, Hg), radionuklida (40K, 226Ra, 232Th, 238U, 137Cs) i njihova prostorna raspodela u zalivu. Pre instrumentalnih analiza, određene su fizičko-hemijske katakteristike sedimenta, poput granulometrijskog sastava, sadržaja organske materije i karbonata. U okviru doktorske disertacije, jedan deo istraživanja odnosio se na procenu ekološkog i radiološkog rizika za period 2019. godine. Za procenu ekološkog statusa sedimenta primenjeni su individualni indeksi, poput faktora obogaćenja (EF), geoakumulacionog indeksa (Igeo), faktora kontaminacije (Cf), zatim i kompleksni indeks, kao što je indeks opterećenja zagađenjem (PLI); koji su se zasnivali na vrednostima potencijalno toksičnih elemenata (Al, Fe, Mn, Cr, Zn, Ni, Cu, Pb, As, Co, U). Primenom individualnih indeksa zagađenja (EF, Cf, Igeo), okriveno je umereno i umereno-do-jako zagađenje u Tivatskom zalivu za većinu teških metala (Ni, Cr, Zn, Cu, As i Pb), što je ukazalo na očigledan uticaj antropogenih aktivnosti koji je doprineo kontaminaciji sedimenta. Primenom PLI, utvrđen je ukupan obim opterećenja teških metala za svaku lokaciju, čime je ukazano na visok nivo zagađenja na lokaciji Bijela brodogradilište. Metode multivarijacione statističke analize istakle su sličnosti odnosno razlike u distribuciji pojedinih ispitivanih elemenata u skladu sa njihovm poreklom. Da bi se obezbedila radiološka procena rizika morskih sedimenata u 2019. godini, najpre je izvršena analiza sadržaja prirodnih radionuklida (40K, 226Ra, 232Th, 238U) i tehnogenog cezijuma (137Cs). Primenjeno je nekoliko dobro utvrđenih parametara (doza zračenja i indeksa), i to spoljašnjih hazard indeksa: ekvivalent aktivnosti radijuma (Raeq), ukupna apsorbovana doza (D), eksterni hazard indeks (Hex), rizik od nastanka kancera tokom života (ELCR); i unutrašnjih hazard indeksa: interni hazard indeks (Hin), godišnja efektivna doza (AEDE), godišnji ekvivalent gonadne doze (AGDE), i indeks iskorišćenja aktivnosti (AUI). Rezultati dobijenih indeksa ukazuju na to da je rizik usled gama zračenja u ispitivanom području u okviru prihvatljivog nivoa. Mape prostorne raspodele radionuklida upućivale su na izraženiju primordijalnu radioaktivnost u unutrašnjem delu zaliva. Korelaciona i klasterska analiza otkrile su snažnu povezanost između primordijalnih radionuklida i većine makroelemenata i napravile jasnu razliku između 226Ra, 232Th, 238U i 137Cs. Drugi deo ovog istraživanja predstavljao je sveobuhvatnu procenu statusa kvaliteta sedimenta, odnosno procenu potencijalne kontaminacije sedimenta. Evaluacija sedimenta izvršena je uporednom analizom vrednosti razmatranih pokazatelja ekološkog rizika i indeksa zagađenja, praćenih na četrdeset lokacija u Bokokotorskom zalivu u različitim sezonama u periodu od 2005. do 2019. godine. U cilju procene potencijalnog ekološkog rizika, ekotoksičnosti sedimenta, identifikacije nivoa toksičnosti i ukupnog opterećenja kontaminacije razmatranih teških metala (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe), primenjeni su indeksi poput indeksa opterećenja zagađenjem (PLI), indeksa potencijalnog ekološkog rizika (RI), prosečnog ERM kvocijenta (MERMQ), indeksa toksičnog rizika (TRI) i indeksa jačine kontaminacije (CSI). Nekoliko žarišta u zalivu vizuelno su predstavljena prostornom distribucijom ovih indeksa zagađenja, ukazujući da je sediment u Tivatskom zalivu bio najzagađeniji u okviru ispitivanog područja. Utvrđen je prosečni doprinos pojedinih metala u ukupnom riziku, predstavljen sledećim redosledom: Cd > Hg > As > Pb > Ni > Cu > Cr > Zn. S obzirom na najveći doprinos ukupnom riziku, prisustvo Cd predstavlja prioritet usled toksičnosti koji izaziva veliku zabrinutost u okviru ekosistema zaliva. Na osnovu rezultata, postoji opadajući trend vrednosti sadržaja Hg zabeležen u periodu od 2005. do 2019. godine. Na osnovu rezultata dobijenih indeksima zagađenja ukazano je na Tivatski zaliv kao najzagađeniji deo ispitivanog područja, kako za 2019. godinu, tako i za istraživani period od 2005. do 2019., što je potvrđeno i metodama multivarijacione analize. Multivarijacione statističke metode podržale su primenu smanjenog broja kompleksnih indeksa, s obzirom da je većina njih upućivala na relativno slične zaključke u proceni rizika.Marine surface sediment sampled in December 2019 at twelve locations in the Boka Kotorska Bay was analyzed using different instrumental methods to achieve chemical, textural and radiological characterization of sediment. The content was determined for ten oxides and twenty-six elements (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2, TiO2, As, Ba, Br, Cl, Co, Cr, Cs, Cu, Ga, La, Mo, Nb, Ni, Pb, Rb, S, Sb, Se, Sn, Sr, Th, U, V, Y, Zn, Zr), heavy metals (Cd, Hg), radionuclides (40K, 226Ra, 232Th, 238U, 137Cs) was determined, as well as their spatial distribution in the Bay. Before instrumental analysis, physico-chemical characteristics of the sediment were determined, such as granulometric composition, organic matter content and carbonate content. Within the doctoral dissertation, one part of the research referred to the assessment of environmental and radiological risk for the period 2019. Individual indices, such as enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (Cf); and complex index, such as pollution load index (PLI), were applied to assess the ecological status of the sediment, which were based on the values of potentially toxic elements (Al, Fe, Mn, Cr, Zn, Ni, Cu, Pb, As, Co, U). Moderate and moderate-to-strong pollution has been identified in the Tivat Bay for most heavy metals (Ni, Cr, Zn, Cu, As and Pb) using the individual pollution indices EF, Cf and Igeo, which indicated the obvious impact of anthropogenic activities that contributed to sediment contamination. Combining the number of analyzed heavy metals, PLI determined the total heavy metal load for each site, indicating a high level of pollution at the site Bijela shipyard. The multivariate statistical analysis highlighted the similarities and differences in the distribution of individual examined elements in the Bay by their origin. To provide a radiological risk assessment of marine sediments in 2019, the sediment has been first analyzed for the content of natural, primordial radionuclides (40K, 226Ra, 232Th, 238U) and technogenic cesium (137Cs). Several well-established parameters (radiation doses and indices) were applied, such as, external hazard indices: radium equivalent activities (Raeq), absorbed dose rate (D), external hazard index (Hex), excess lifetime cancer risk (ELCR); and internal hazard indices: internal hazard index (Hin), annual effective dose rate (AEDE), annual gonadal dose equivalent (AGDE), activity utilization index (AUI). The results of the obtained indices suggest that the risk due to gamma radiation in the investigated area is within an acceptable level. Spatial distribution maps of radionuclides indicated that primordial radioactivity was more concentrated in the inner part of the Bay. Correlation and cluster analysis revealed a strong association between primordial radionuclides and most macroelements and a clear difference between 226Ra, 232Th, 238U and 137Cs. The second part of this research was a comprehensive assessment of the sediment quality status, that is, an assessment of potential sediment contamination. The sediment evaluation was performed by a comparative analysis of the values of the considered environmental risk indicators and pollution indices, monitored at forty locations in the Boka Kotorska Bay in different seasons in the period from 2005 to 2019. To assess the potential environmental risk, sediment ecotoxicity, identification of toxicity levels and total contamination load of the considered heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe), indices such as Pollution Load Index (PLI), Potential Ecological Risk Index (RI), Mean ERM Quotient (MERMQ), Toxic Risk Index (TRI), and Pollution Contamination Index (CSI) were applied. Several hotspots in the Bay were visually represented by the spatial distribution of these pollution indices, indicating that the sediment in Tivat Bay was the most polluted within the study area. The average contribution of individual metals in the total risk was determined, presented in the following order: Cd > Hg > As > Pb > Ni > Cu > Cr > Zn. Considering the highest contribution to the overall risk, the presence of Cd is a priority due to the toxicity that causes great concern within the ecosystem of the Bay. Based on the results, there is a declining trend of Hg content observed in the period from 2005 to 2019. Based on the results obtained by pollution indices, the bay of Tivat was the most polluted part of the investigated area, both in 2019 and in the period from 2005 to 2019, which was confirmed by the methods of multivariate analysis. Multivariate statistical methods supported the application of a reduced number of complex indices, as most of them pointed to relatively similar conclusions in the risk assessment

Raw clays in the production of ceramic and refractory tiles

Raw clay samples from Serbia, mainly of kaolinitic, illitic and mixed nature, were tested for their possible application in the production of ceramics. Using various triaxial diagrams, the samples were sorted according to their chemical and bulk mineralogical makeup, and also particle size distribution to determine whether they could be employed in the production of ceramics and refractories. The areas in the ternary graphs determined in earlier studies concerning the expected color after firing and the applicability of the raw clays are checked and extended. The samples' water absorption and flexural strength were assessed using EN standard procedures after they had been hydraulically semi-dry pressed and fired at several peak temperatures between 1100 and 1300 °C. A novel triaxial diagram considering the position of the samples based on firing temperature, water absorption and modulus of rupture is proposed, and the areas of different kinds of ceramic tiles are defined. It is discovered that the different raw clays can be utilized to create refractory, as well as wall and floor tiles. This study supports the rational use of natural sources of raw materials

Spatial distribution and identification of elements and oxides in surface sediments of the Boka Kotor bay

Ovo istraživanje sprovedeno je u Bokokotorskom zalivu radi procene kvaliteta površinskog sedimenata, a time i stanja morske sredine. ED-XRF metodom elementarne analize određen je sadržaj velikog broja elemenata i oksida u površinskim sedimentima uzorkovanih sa 12 lokacija u 2019. godini. Multivarijantnom statističkom analizom, kao što su analiza glavnih komponenati (PCA) i klaster analiza (CA), urađena je analiza dobijenih podataka kako bi se dobila sveobuhvatna raspodela ispitivanih elemenata po lokacijama u zalivu i njihovo poreklo, kao i sličnosti/razlike grupa uzoraka u hemijskom sastavu.This study was carried out in the Bay of Boka Kotor in order to assess the surface sediment quality and thereby to evaluate the status of the marine environment. The method of elementary analysis, ED-XRF was used to determine the content of elements and oxides in surface sediments sampled at 12 stations in 2019. Multivariate statistical methods, such as principal component analysis (PCA) and cluster analysis (CA) were used to analyse the data in order to obtain a comprehensive distribution of the examined elements according to locations in the bay, and their origin, as well as similarities/differences of samples in chemical composition.49. godišnja konferencije o aktuelnim problemima korišćenja i zaštite voda „Voda 2020“, Trebinje, 19. – 20. novembar 2020

Pollution and risk assessment of the surface sediment of the Boka Kotorska Bay with heavy metals and radionuclides due to their bioavailability

Površinski morski sediment uzorkovan u decembru 2019. godine na dvanaest lokacija u Bokokotorskom zalivu, analiziran je primenom različitih instrumentalnih metoda u cilju postizanja hemijske, teksturalne i radiološke karakterizacije sedimenta. Određen je sadržaj deset oksida i dvadeset šest elemenata (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2, TiO2, i As, Ba, Br, Cl, Co, Cr, Cs, Cu, Ga, La, Mo, Nb, Ni, Pb, Rb, S, Sb, Se, Sn, Sr, Th, U, V, Y, Zn, Zr), dodatnih teških metala (Cd, Hg), radionuklida (40K, 226Ra, 232Th, 238U, 137Cs) i njihova prostorna raspodela u zalivu. Pre instrumentalnih analiza, određene su fizičko-hemijske katakteristike sedimenta, poput granulometrijskog sastava, sadržaja organske materije i karbonata. U okviru doktorske disertacije, jedan deo istraživanja odnosio se na procenu ekološkog i radiološkog rizika za period 2019. godine. Za procenu ekološkog statusa sedimenta primenjeni su individualni indeksi, poput faktora obogaćenja (EF), geoakumulacionog indeksa (Igeo), faktora kontaminacije (Cf), zatim i kompleksni indeks, kao što je indeks opterećenja zagađenjem (PLI); koji su se zasnivali na vrednostima potencijalno toksičnih elemenata (Al, Fe, Mn, Cr, Zn, Ni, Cu, Pb, As, Co, U). Primenom individualnih indeksa zagađenja (EF, Cf, Igeo), okriveno je umereno i umereno-do-jako zagađenje u Tivatskom zalivu za većinu teških metala (Ni, Cr, Zn, Cu, As i Pb), što je ukazalo na očigledan uticaj antropogenih aktivnosti koji je doprineo kontaminaciji sedimenta. Primenom PLI, utvrđen je ukupan obim opterećenja teških metala za svaku lokaciju, čime je ukazano na visok nivo zagađenja na lokaciji Bijela brodogradilište. Metode multivarijacione statističke analize istakle su sličnosti odnosno razlike u distribuciji pojedinih ispitivanih elemenata u skladu sa njihovm poreklom. Da bi se obezbedila radiološka procena rizika morskih sedimenata u 2019. godini, najpre je izvršena analiza sadržaja prirodnih radionuklida (40K, 226Ra, 232Th, 238U) i tehnogenog cezijuma (137Cs). Primenjeno je nekoliko dobro utvrđenih parametara (doza zračenja i indeksa), i to spoljašnjih hazard indeksa: ekvivalent aktivnosti radijuma (Raeq), ukupna apsorbovana doza (D), eksterni hazard indeks (Hex), rizik od nastanka kancera tokom života (ELCR); i unutrašnjih hazard indeksa: interni hazard indeks (Hin), godišnja efektivna doza (AEDE), godišnji ekvivalent gonadne doze (AGDE), i indeks iskorišćenja aktivnosti (AUI). Rezultati dobijenih indeksa ukazuju na to da je rizik usled gama zračenja u ispitivanom području u okviru prihvatljivog nivoa. Mape prostorne raspodele radionuklida upućivale su na izraženiju primordijalnu radioaktivnost u unutrašnjem delu zaliva. Korelaciona i klasterska analiza otkrile su snažnu povezanost između primordijalnih radionuklida i većine makroelemenata i napravile jasnu razliku između 226Ra, 232Th, 238U i 137Cs. Drugi deo ovog istraživanja predstavljao je sveobuhvatnu procenu statusa kvaliteta sedimenta, odnosno procenu potencijalne kontaminacije sedimenta. Evaluacija sedimenta izvršena je uporednom analizom vrednosti razmatranih pokazatelja ekološkog rizika i indeksa zagađenja, praćenih na četrdeset lokacija u Bokokotorskom zalivu u različitim sezonama u periodu od 2005. do 2019. godine. U cilju procene potencijalnog ekološkog rizika, ekotoksičnosti sedimenta, identifikacije nivoa toksičnosti i ukupnog opterećenja kontaminacije razmatranih teških metala (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe), primenjeni su indeksi poput indeksa opterećenja zagađenjem (PLI), indeksa potencijalnog ekološkog rizika (RI), prosečnog ERM kvocijenta (MERMQ), indeksa toksičnog rizika (TRI) i indeksa jačine kontaminacije (CSI). Nekoliko žarišta u zalivu vizuelno su predstavljena prostornom distribucijom ovih indeksa zagađenja, ukazujući da je sediment u Tivatskom zalivu bio najzagađeniji u okviru ispitivanog područja. Utvrđen je prosečni doprinos pojedinih metala u ukupnom riziku, predstavljen sledećim redosledom: Cd > Hg > As > Pb > Ni > Cu > Cr > Zn. S obzirom na najveći doprinos ukupnom riziku, prisustvo Cd predstavlja prioritet usled toksičnosti koji izaziva veliku zabrinutost u okviru ekosistema zaliva. Na osnovu rezultata, postoji opadajući trend vrednosti sadržaja Hg zabeležen u periodu od 2005. do 2019. godine. Na osnovu rezultata dobijenih indeksima zagađenja ukazano je na Tivatski zaliv kao najzagađeniji deo ispitivanog područja, kako za 2019. godinu, tako i za istraživani period od 2005. do 2019., što je potvrđeno i metodama multivarijacione analize. Multivarijacione statističke metode podržale su primenu smanjenog broja kompleksnih indeksa, s obzirom da je većina njih upućivala na relativno slične zaključke u proceni rizika.Marine surface sediment sampled in December 2019 at twelve locations in the Boka Kotorska Bay was analyzed using different instrumental methods to achieve chemical, textural and radiological characterization of sediment. The content was determined for ten oxides and twenty-six elements (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2, TiO2, As, Ba, Br, Cl, Co, Cr, Cs, Cu, Ga, La, Mo, Nb, Ni, Pb, Rb, S, Sb, Se, Sn, Sr, Th, U, V, Y, Zn, Zr), heavy metals (Cd, Hg), radionuclides (40K, 226Ra, 232Th, 238U, 137Cs) was determined, as well as their spatial distribution in the Bay. Before instrumental analysis, physico-chemical characteristics of the sediment were determined, such as granulometric composition, organic matter content and carbonate content. Within the doctoral dissertation, one part of the research referred to the assessment of environmental and radiological risk for the period 2019. Individual indices, such as enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (Cf); and complex index, such as pollution load index (PLI), were applied to assess the ecological status of the sediment, which were based on the values of potentially toxic elements (Al, Fe, Mn, Cr, Zn, Ni, Cu, Pb, As, Co, U). Moderate and moderate-to-strong pollution has been identified in the Tivat Bay for most heavy metals (Ni, Cr, Zn, Cu, As and Pb) using the individual pollution indices EF, Cf and Igeo, which indicated the obvious impact of anthropogenic activities that contributed to sediment contamination. Combining the number of analyzed heavy metals, PLI determined the total heavy metal load for each site, indicating a high level of pollution at the site Bijela shipyard. The multivariate statistical analysis highlighted the similarities and differences in the distribution of individual examined elements in the Bay by their origin. To provide a radiological risk assessment of marine sediments in 2019, the sediment has been first analyzed for the content of natural, primordial radionuclides (40K, 226Ra, 232Th, 238U) and technogenic cesium (137Cs). Several well-established parameters (radiation doses and indices) were applied, such as, external hazard indices: radium equivalent activities (Raeq), absorbed dose rate (D), external hazard index (Hex), excess lifetime cancer risk (ELCR); and internal hazard indices: internal hazard index (Hin), annual effective dose rate (AEDE), annual gonadal dose equivalent (AGDE), activity utilization index (AUI). The results of the obtained indices suggest that the risk due to gamma radiation in the investigated area is within an acceptable level. Spatial distribution maps of radionuclides indicated that primordial radioactivity was more concentrated in the inner part of the Bay. Correlation and cluster analysis revealed a strong association between primordial radionuclides and most macroelements and a clear difference between 226Ra, 232Th, 238U and 137Cs. The second part of this research was a comprehensive assessment of the sediment quality status, that is, an assessment of potential sediment contamination. The sediment evaluation was performed by a comparative analysis of the values of the considered environmental risk indicators and pollution indices, monitored at forty locations in the Boka Kotorska Bay in different seasons in the period from 2005 to 2019. To assess the potential environmental risk, sediment ecotoxicity, identification of toxicity levels and total contamination load of the considered heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe), indices such as Pollution Load Index (PLI), Potential Ecological Risk Index (RI), Mean ERM Quotient (MERMQ), Toxic Risk Index (TRI), and Pollution Contamination Index (CSI) were applied. Several hotspots in the Bay were visually represented by the spatial distribution of these pollution indices, indicating that the sediment in Tivat Bay was the most polluted within the study area. The average contribution of individual metals in the total risk was determined, presented in the following order: Cd > Hg > As > Pb > Ni > Cu > Cr > Zn. Considering the highest contribution to the overall risk, the presence of Cd is a priority due to the toxicity that causes great concern within the ecosystem of the Bay. Based on the results, there is a declining trend of Hg content observed in the period from 2005 to 2019. Based on the results obtained by pollution indices, the bay of Tivat was the most polluted part of the investigated area, both in 2019 and in the period from 2005 to 2019, which was confirmed by the methods of multivariate analysis. Multivariate statistical methods supported the application of a reduced number of complex indices, as most of them pointed to relatively similar conclusions in the risk assessment

Accumulation of heavy metal(loid)s and polycyclic aromatic hydrocarbons in the sediment of the Prahovo Port (Danube) and associated risks

The current study investigated the concentrations, possible sources, toxicity, and ecological risk of eight heavy metal(loid)s (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) and sixteen priority polycyclic aromatic hydrocarbons (PAHs) in surface sediments in the port of Prahovo (Danube, Serbia). Among the examined HMs, the most abundant was Cu (38.3 mg/kg), followed by Zn. The Σ16PAHs concentrations ranged from 25 to 112.5 µg/kg, with 4-ring PAHs (17.3 µg/kg) being the most dominant in the study area. The mean and maximum values of HMs and PAHs obtained in this study were below the national regulatory limits and within environmental criteria. Particularly significant correlations between As, Cd, Cr, Ni, Pb, Zn, 5-, 6-ring PAHs, as well as between Pb and Hg, indicated their similar anthropogenic sources, pathways, and adsorption mechanisms. These findings were confirmed by cluster analysis and principal component analysis. Diagnostic ratios demonstrated that contamination in inner port stations was characterized by pyrogenic sources, while PAHs of petrogenic origin prevailed in samples near the port entrance. The mean ERM quotient (mERMq), toxic risk index (TRI), and toxic equivalent quotient (TEQ) were also calculated to assess the toxicity of the investigated HMs and PAHs in sediments. Positive matrix factorization suggested four potential sources as the main components of sediment contamination, whereas the risk assessment indicated a low or relatively insignificant risk of adverse biological effects from the combined toxicity of HMs and PAHs for the entire study area

Fired pressed pellet as a sample preparation technique of choice for an energy dispersive X-ray fluorescence analysis of raw clays

In this paper, the main subject concerns comparing different techniques to prepare raw clay samples for energy-dispersive X-ray fluorescence spectrometry (EDXRF). Three kinds of sample preparation procedures are examined, such as loose powder, pressed pellet, and fired pressed pellet. The fired pressed pellet approach was observed as a part of universal sample preparation for physic, mechanical, and instrumental analysis, which has not been previously tested as a solution in chemical analysis by the EDXRF method. The observed sample preparation techniques were compared by calculating the parameters of validation (recoveries, limit of detection - LOD, limit of quantification - LOQ, precision, and expanded uncertainties of measurements) of 11 elements (Si, Al, Fe, Ca, Mg, K, Na, Ti, P, Mn, and S) using 15 certified reference materials (CRMs). Calibration curves were created and evaluated using 30 reference materials (RM) for all three approaches. Results proved that the fired pressed pellet is the most practical and precise approach for sample preparation of raw clays

Pečeni presovani pelet kao tehnika pripreme uzorka sirovih glina za hemijsku analizu pomoću energetsko disperzivne rendgensko fluorescentne spektrometrije

KORISNIK TEHNIČKOG REŠENJA: Institut za ispitivanje materijala IMS a.d.iz Beograd

An augmented approach for the determination of the particle size effect on energy dispersive X-ray fluorescence analysis outcomes for alumina-based refractory materials

The chemical compositions of refractory materials, such as high-alumina concrete, bricks, and putty, were analyzed using an energy-dispersive X-ray spectrometer (EDXRF). An improved methodology for investigating the effect of particle size on the outcomes of EDXRF chemical analysis is presented. Eight independent refractory samples (refractory concrete, brick, and putty) were pulverized utilizing seven milling times (30, 60, 120, 180, 240, 300, and 360 s) and compared to non-pulverized samples. Thus, sixty-four refractory samples were obtained and analyzed using EDXRF. The method for measuring the fundamental EDXRF characteristics was then tested with ten certified reference materials. The acquired data were compared using inductively coupled plasma atomic emission spectrometry (ICP-OES). Univariate and multivariate statistics are used to evaluate EDXRF data. The particle size of the tested samples affected the z-scores of SiO2, Al2O3, Fe2O3, TiO2, CaO, MgO, Na2O, K2O, and P2O5 concentration measurements. Grinding times for refractory concrete, brick, and putty samples were determined in order to validate the robustness of the EDXRF technique and provide reliable chemical analyses. The ideal milling times for the samples studied ranged from 180 to 360 s, depending on the type of refractory material

GEOSPATIAL MAPPING OF ECOLOGICAL RISK FROM POTENTIALLY TOXIC ELEMENTS IN SOIL IN THE PANNONIAN-CARPATHIAN BORDER AREA SOUTH OF THE DANUBE

This study collected agricultural surface soil samples from 200 sites in the district of Braničevo, located in the Carpathian Mountains – Pannonian Basin south of the Danube River (Serbia). The main objective was to determine the soil contamination by ten potentially toxic elements (As, B, Cd, Cr, Cu, Mn, Mo, Ni, Pb, Zn) and evaluate the associated ecological risk via different indices. The physicochemical parameters, pH, organic carbon, water content, and soil texture were also analyzed. The mean values of most metal concentrations remained below their corresponding national target values, except for Mo and Ni. The main soil texture types were silt loam (40.5 %) and silty clay loam (34.5 %). According to the mean values, pollution load index (PLI) and potential ecological risk (RI) demonstrated that the soil in the study area was exposed to moderate pollution and moderate ecological risk, while enrichment factor (EF), geoaccumulation index (Igeo), and contamination factor (CF) revealed very high enrichment and contamination with Mo, implying the impact of anthropogenic activities. There was a lack of strong correlations among elements and soil properties, except for Cd and Corg, while moderate to strong positive inter-metal relationships suggested their common sources. The chemometric analysis illustrated the classification of sampling sites into two distinct clusters of spatial similarities according to higher and lower metal concentrations. Geospatial mapping identified a few areas of considerable ecological risk. © 2022,Carpathian Journal of Earth and Environmental Sciences. All Rights Reserved