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1.
Sci Total Environ ; 505: 724-31, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25461075

RESUMO

The spatial variability of the mineral composition of grapevines in production vineyards along the east Adriatic coast was determined and compared between conventional and sustainable vineyard management. Cluster analysis shows a high level of spatial variability even within the individual locations. Factor analysis reveals three factors with strong loading for the macronutrients K and P and the micronutrient Mn, which explain 67% of the total variance in the mineral composition. Here, 26% to 34% of the variance of these three elements can be explained by abiotic and biotic soil parameters, with soil concentrations of K, Fe and Cu, organic matter content, and vesicular colonisation showing the strongest effects on the mineral composition of the grapevines. In addition, analysis of the mineral composition data shows significant differences between differently managed vineyards, with increased bioaccumulation of P and K in sustainable vineyards, while Zn bioaccumulation was increased in conventional vineyards. Our data confirm the importance of soil and vineyard management in the concept of terroir, and demonstrate the effects of sustainable management practices on the mineral nutrition of grapevines that result from modified nutrient availability related to changes in the abiotic and biotic characteristics of the soil.


Assuntos
Agricultura/métodos , Minerais/análise , Solo/química , Vitis/química , Fertilizantes , Micronutrientes/análise
2.
Appl Radiat Isot ; 87: 238-41, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24373873

RESUMO

The methods of electrodeposition and "molecular plating" were studied for the production of uranium targets with an areal density up to 0.6 mg cm(-2) on aluminium and up to 1.5 mg cm(-2) on stainless steel backings from aqueous and organic electrolytes. For characterisation of the deposited material, gamma-ray spectrometry, alpha-particle spectrometry, X-ray fluorescence, X-ray powder diffraction, scanning electron microscopy and autoradiography were applied.

3.
Appl Radiat Isot ; 87: 61-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24359791

RESUMO

A comparison of different dissolution techniques for determination of uranium in soil samples was made. Conventional wet dissolution with mixtures of HNO3, HClO4 and HF acids, microwave dissolution using HNO3 and HF, and alkaline fusion with Na2CO3 and Na2O2 were evaluated. For testing the effectiveness of the dissolution procedures, two reference materials and six soil samples from the surroundings of a former uranium mine were investigated. It was observed that the content of uranium in the residues determined by INAA represents a significant contribution to its total concentration in the sample, especially in the case of microwave dissolution.

4.
Environ Geochem Health ; 29(1): 69-79, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17203367

RESUMO

The present work was designed as an extension of a previous study of a barium anomaly observed in stream sediments of the Kupa River. In its upper part the Kupa River drains a region underlain by a trans-boundary aquifer. The river is a significant water resource in a region of tourism, sport, and fishing in both Croatia and Slovenia. The contamination source is situated in Homer (Lokve), Croatia, where barite was mined until 10 years ago. The barium processing waste material (<3-mm fraction) was carelessly deposited in gardens, forests, and into a sinkhole, which has an underground link with the Kupica River, a tributary of the Kupa River. Barium waste and stream sediments were analyzed using comparative techniques: X-ray diffraction (XRD), X-ray fluorescence (XRF), Mössbauer spectroscopy, and grain size analysis. XRD of the waste material identified the major minerals quartz, barite, and dolomite and the Fe-containing minor minerals muscovite and goethite. Barite was identified as a minor or trace mineral in the Kupica River sediments. XRF analysis of the waste material has shown Ba and Fe to be the predominant elements, Ca and K to be minor elements, and Mn, Zn, Sr, Pb, Co, Cu, As, Zr, Rb, Y, and Mo to be trace elements. Mössbauer spectroscopy performed at room temperature (RT) was used to study iron minerals, particularly to obtain information on the valence status of Fe ions. Grain size analysis of the waste material (<63-microm fraction) has shown that it contains 23.5% clay-size material in comparison with 7-8% clay-size material in stream sediments. It is our aim to combine geochemical and medical methods to investigate the possible impact of waste disposal on human health in Lokve. At this stage of the work, concentrations of Ba and other toxic elements in the water compartment of the Kupica River (a source of drinking water) have not been monitored by Croatian Waters (name of the Croatian water authorities). The necessity of such measurements in future studies has been highlighted. A preliminary study of diseases diagnosed in Lokve shows that about 18% of the total inhabitants have serious medical problems. Diseases of the circulatory system, endocrine, nutritional, and metabolic diseases, neoplasms, and respiratory diseases predominate. This paper calls for further multidisciplinary research on the health effects of barium and trace elements, as well as for bioremediation of contaminated gardens and for watershed management of vulnerable karstic aquifers.


Assuntos
Bário/análise , Monitoramento Ambiental , Rios/química , Poluentes Químicos da Água/análise , Bário/química , Conservação dos Recursos Naturais , Croácia , Sedimentos Geológicos/química , Nível de Saúde , Humanos , Isótopos de Ferro/análise , Tamanho da Partícula , Eslovênia , Espectrometria por Raios X , Espectroscopia de Mossbauer , Movimentos da Água , Poluentes Químicos da Água/química , Difração de Raios X
5.
Sci Total Environ ; 207(2-3): 141-8, 1997 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-9447743

RESUMO

With the ultimate objective in contributing to the improvement of the quality control of drinking water and to facilitate the checking of its compliance with the respective regulations, an inventory of analytical techniques used in water supply companies in Eastern and Western European countries is presented. The existing regulations for drinking water and bottled mineral water quality with respect to trace elements in these countries are compared to regulations of the World Health Organisation. The data obtained can be useful for further harmonisation of the respective regulations in Europe.


Assuntos
Técnicas de Química Analítica/métodos , Oligoelementos/análise , Abastecimento de Água/legislação & jurisprudência , Abastecimento de Água/normas , Ingestão de Líquidos , Europa (Continente) , Europa Oriental , Espectrofotometria Atômica
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