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1.
Artigo em Inglês | MEDLINE | ID: mdl-36232178

RESUMO

To determine the nature and origin of the unconsolidated bottom sediments, as well as to demonstrate and quantify the presence of Presumably Contaminating Elements (PCE) in the Serbian Danube River, as a novelty, the mass fractions on nine major elements as oxides-SiO2, TiO2, Al2O3, FeO, MnO, MgO, CaO, Na2O, and K2O, as well as Sc, V, Cr, Co, Ni, Cu, Zn, As, Rb, Sr, Zr, Sb, Cs, Ba, La, Hf, Ta, W, Th, and U were determined by Instrumental Neutron Activation Analysis (INAA) in 13 sediment samples collected between Belgrade and Iron Gate 2 dam. INAA was chosen for its ability to perform elemental analysis without any preliminary sample treatment that could introduce systematic errors. The distribution of major elements was relatively uniform, with the sampling locations having less influence. Concerning the trace elements, excepting the PCE Cr, Ni, Cu, Zn, As, and Sb, their distributions presented the same remarkable similarity to the Upper Continental Crust (UCC), North American Shale Composite (NASC), Average Bottom Load (ABL), and Average Dobrogea Loess (AVL), and were in good concordance with the location of the Serbian Danube River in the Pannonian Plain. In the case of considered PCE, both Enrichment Factor and Pollution Load Index showed values higher than the pollution threshold, which pointed towards a significant anthropogenic contamination, and rising concern to what extent the water quality and biota could be affected.


Assuntos
Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos/análise , Ferro/análise , Óxido de Magnésio/análise , Metais Pesados/análise , Rios , Sérvia , Dióxido de Silício/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise
2.
Environ Sci Pollut Res Int ; 24(6): 5717-5732, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28039634

RESUMO

The total content of 8 major and 32 trace elements in four species of mosses and two of lichens as well as neighboring soil and rocks collected from different places of the Livingston Island Antarctica was determined by instrumental neutron activation analysis. The main goals of the project consisted of evidencing the possible trace of anthropogenic contamination as well as the influence of altitude on the distribution of considered elements. In the absence of a unanimously accepted descriptor, enrichment factor, geo-accumulation, and pollution load indices with respect to soil and rocks were used. The data, interpreted within the model of a reference plant, were compared with previous studies regarding the same organisms in similar geographic and climatological areas. The experimental results evidenced different capacity of mosses and lichens to retain the considered elements, but within experimental uncertainties, no traces of anthropogenic pollution were found. At the same time, it was found that the content of most of the elements decreased with the altitude.


Assuntos
Briófitas , Poluição Ambiental , Líquens , Análise de Ativação de Nêutrons , Oligoelementos/análise , Altitude , Regiões Antárticas , Monitoramento Ambiental/métodos , Ilhas , Solo
3.
Bull Environ Contam Toxicol ; 98(2): 262-269, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27889805

RESUMO

Moss biomonitoring using the species Hypnum cupressiforme (Hedw.) and Pleurocarpous sp was applied to study air pollution in the Republic of Moldova. A total of 41 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Cd, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Hf, Ta, W, Pb, Th, and U) were determined by instrumental epithermal neutron activation analysis and atomic absorption spectrometry. Principal component analysis was used to identify and characterize different pollution sources. Geographical distribution maps were prepared to point out the regions most affected by air pollution and relate this to potential sources of contamination. Median values of the elements studied were compared with data from the European moss biomonitoring program. The cities of Chisinau and Balti were determined to experience particular environmental stress.


Assuntos
Poluição do Ar/análise , Bryopsida/química , Monitoramento Ambiental , Metais/análise , Moldávia , Análise de Ativação de Nêutrons , Análise de Componente Principal , Espectrofotometria Atômica
4.
Bull Environ Contam Toxicol ; 96(5): 650-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27003805

RESUMO

The moss-bag transplant technique was used to investigate the kinetics of the accumulation of 38 elements in Sphagnum girgensohni moss samples in the highly polluted municipality of Baia Mare, Romania. The moss samples collected from the unpolluted Vitosha Mountain Natural Reserve, Bulgaria, were analyzed after 1, 2, 3, and 4 months of exposure, respectively. The ANOVA method was used to assay the statistical significance of the observed changes in elemental content, as determined by neutron activation analysis. The content of Zn, Se, As, Ag, Cd, and Sb increased steadily, while that of physiologically active K and Cl, as well as Rb and Cs, decreased exponentially. The study showed that an adequate application of the moss transplant technique in an urban environment should consider the exposure time as a critical parameter, since particular elements are depleted in the moss at sites with high atmospheric loading of metals.


Assuntos
Poluentes Ambientais/análise , Sphagnopsida/química , Arsênio/análise , Cidades , Monitoramento Ambiental/métodos , Indústrias , Metais/análise , Análise de Ativação de Nêutrons , Romênia , Fatores de Tempo
5.
Mar Pollut Bull ; 58(6): 827-31, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19261305

RESUMO

The vertical distributions of five potential pollutants - Zn, As, Br, Sn, and Sb - were determined via epithermal neutron activation in the upper 50cm of unconsolidated sediments from the Black Sea, which were collected 600m below sea surface. This analysis demonstrated increasing concentrations towards the upper limits of sediments, which were greater than alert concentrations in the case of As and Br, and in accordance with Romanian Environment Regulations. The utilization of Chernobyl (137)Cs as a time marker allowed for dating of this region to the last 100 years.


Assuntos
Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Antimônio/análise , Arsênio/análise , Bromo/análise , Radioisótopos de Césio , Análise de Ativação de Nêutrons , Oceanos e Mares , Tempo , Estanho/análise , Zinco/análise
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