Találati lista | Tudóstér

001-es BibID:	BIBFORM090106
035-os BibID:	(cikkazonosító)104029
Első szerző:	Heltai György
Cím:	Application of flexible multi-elemental ICP-OES detection in fractionation of potentially toxic element content of solid environmental samples by a sequential extraction procedure / Heltai György, Győri Zoltán, Fekete Ilona, Halász Gábor, Kovács Katalin, Takács Anita, Lamlile Khumalo, Horváth Márk
Dátum:	2019
ISSN:	0026-265X
Megjegyzések:	Remediation of areas contaminated by potentially toxic elements (PTE) requires the appropriate assessment of the environmental mobility of contaminants. The fractionation techniques developed for agrochemical and environmental purposes model the pathways of environmental mobilization mainly by sequential extraction procedures. In Europe mostly the simplified extraction scheme proposed by Community Bureau of Reference (BCR) in 1993 is widely used, why only to this certified sediment sample (BCR 701) is available, certified for fractionation of six elements (Cu, Cd, Cr, Ni, Pb, Zn). In the BCR extracts the reagent- solvents applied in leaching steps cause strong matrix interferences when for determination the PTE-contents of these solutions the multielemental capacity of inductively coupled plasma optical emission spectrometry (ICP-OES) should be utilized. Due to the different source of contamination the flexible multi-elemental ICP-OES method should be applied for analysis of the different BCR-extractant-solvent media which makes possible the reliable detection of all occurring PTE in the area. For this purpose as the most adequate solution the application of ICP-OES spectrometer with charge-coupled device (CCD)-detection was selected which is able to record the entire spectral range between 120 and 800?nm. On the basis of detailed study of BCR-solvent-matrix- and expected-analite-line interferences it was established that the sensitivities of the prominent lines of pollutant elements strongly depend on the type of extractants. For improving the accuracy of analytical results obtained for soils and environmental sediments, matrix matched calibration, internal standardization and robust plasma conditions were recommended and optimized. The successful application of this methodology is presented for a PTE-contaminated lake sediment sample and for selected typical Hungarian soil samples stored in sample bank of Hungarian Soil Protection Information and Monitoring System.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Microchemical Journal. - 149 (2019), p. 1-26. -
További szerzők:	Győri Zoltán (1948-) (vegyész) Fekete Ilona Halász Gábor (biokémikus) Kovács Katalin (1978-) (agrokémia) Takács Anita Khumalo, Lamlile Horváth Márk
Pályázati támogatás:	OTKA-108558 Egyéb OTKA-118101 Egyéb 1783-3/2018/FEKUTSTRAT Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM067315
Első szerző:	Heltai György
Cím:	Longterm study of transformation of potentially toxic element pollution in soil/water/sediment system by means of fractionation with sequential extraction procedures / Gy. Heltai, Z. Győri, I. Fekete, G. Halász, K. Kovács, A. Takács, N. Boros, M. Horváth
Dátum:	2018
ISSN:	0026-265X
Megjegyzések:	In first part of the paper a review is given on fractionation methodologies by sequential extraction methodologies applied for risk assessment of environmental pollution by potentially toxic elements (PTE). Main sources of PTE release are the mining-, industrial-, agri-food production-, traffic- and communal-waste. In this latter the medical and health care sources may emerge due to therapeutic and diagnostic applications (Ag, As, Au, Ba, Bi, Cd, Ga, Gd, 131I, Ir, Li, Mn, Fe, Os, Pd, Pt, Rh, Ru, Sb, Sn, Ti, V), to nanomedicines, to ayurvedic herbal medicines with possible contaminant PTEs and non-controlled dietary supplements. The magnitude of adverse effects caused by PTEs in the soil-water-sediment system depends on the various chemical species that can arise. Long-term biological impacts are strongly influenced by mobilization-immobilization processes in the aquatic environment. These can be studied through sequential extraction procedures modelling their pathways. In Europe the simplified extraction scheme proposed by BCR in 1993 and modified in 2001 is mostly used for this purpose. By this approach samples are gradually decomposed and four different fractions of PTEs can be identified, i.e.: i) water-soluble and carbonate-bound fraction; ii) fraction associated with reducible Fe- and Mn-oxides; iii) organic complexed fraction and sulphides; iv) fraction soluble in oxidative acids. The sediment-based Certified Reference Material (CRM) BCR 701 was produced to check the accuracy of the fractionation procedure. The standardization process was hindered by methodological problems, i.e.: i) the solvents used in the BCR system do not mirror completely the natural mobilization processes and partly modify the original chemical species; ii) the time demand of the batch leaching extraction steps is exceedingly long (4-5 days); iii) the above CRM, certified for the fractionation of Cu, Cd, Cr, Ni, Pb and Zn, is available only for sediment and cannot be applied to other environmental matrices and other PTEs. The studies aimed at improving the BCR methodology are summarized, in particular to: i) develop continuous flow systems; ii) accelerate the BCR leaching steps by sonication; iii) extend the BCR procedure to other environmental matrices (soils, red mud, composts, biofilms) and further PTEs by multielemental (ICP-OES) detection.In second part of the paper a case study is presented for evaluation of long-term changes of the environmental mobility of PTE contaminations in the fish pond system of Gödöllő town. For vertical and horizontal mapping of PTE content of accumulated sediment layers core samples were taken in 1994, 1995 and 2013. In the sediment layers total soluble PTE content was related to the BCR fractionation. The Chernobyl origine radionuclides were detected by ?-spectroscopy. The BCR sequential extraction procedure for tracking the long-term fate of PTE contamination of different origine in surface water/sediment/systems showed a much potential. By repetition of fractionation of PTEs after 20 years clearly reflects the change of PTE concentrations in different fractions. The decrease of PTE concentrations can be explained by leaching the most mobile fractions by water exchange over the sediment and/or by remediation activity.
Tárgyszavak:	Műszaki tudományok Bio-, környezet- és vegyészmérnöki tudományok idegen nyelvű folyóiratközlemény külföldi lapban Potentially toxic elements Fractionation BCR sequential extraction ICP-OES multielemental detection of pollutants Risk assessment
Megjelenés:	Microchemical Journal. - 136 (2018), p. 85-93. -
További szerzők:	Győri Zoltán (1948-) (vegyész) Fekete Ilona Halász Gábor (biokémikus) Kovács Katalin Takács Anita Horváth Márk Boros Norbert (1977-) (agrármérnök)
Internet cím:	DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM079997
Első szerző:	Kovács Katalin (agrokémia)
Cím:	Study of ultrasound-assisted sequential extraction procedure for potentially toxic element content of soils and sediments / Katalin Kovács, Gábor Halász, Anita Takács, György Heltai, Éva Széles, Zoltán Győri, Márk Horváth
Dátum:	2018
ISSN:	0026-265X
Megjegyzések:	For risk assessment of potentially toxic element (PTE) pollution of sediments and soils the fractionation by sequential extraction procedures are applied which require longtime leaching-shaking periods to achieve the dissolution equilibria. In this work an attempt is described for reduction the duration these leaching-shaking periods of the sequential extraction procedure proposed by Community Bureau of Reference (BCR) in 1993 by application of ultrasonic treatment. The fractionation of PTE content of BCR 701 certified reference sample was performed in three experiments: "A" experiment was the control, all extraction steps were performed with 16 hours shaking according to the BCR prescription; "B" experiment: in each extraction step was applied 1 hour preliminary ultrasonic treatment and after this 1 hour shaking; "C" experiment: only 1 hour ultrasonic treatment and no shaking was applied. It was experienced that by ultrasonic treatment can be efficiently increased the rate of dissolution when constant temperature of assisting medium was kept. 77% and 63% of element content extractable with the control "A" experiment can be extracted in "B" and "C" experiments, respectively. To achieve the 100% efficiency further experiments are in process.
Tárgyszavak:	Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Microchemical Journal. - 136 (2018), p. 80-84. -
További szerzők:	Halász Gábor (biokémikus) Takács Anita Heltai György Széles Éva (1979-) (vegyész) Győri Zoltán (1948-) (vegyész) Horváth Márk
Internet cím:	Intézményi repozitóriumban (DEA) tárolt változat DOI
Borító:
Saját polcon:

001-es BibID:	BIBFORM088830
035-os BibID:	(cikkazonosító)0096
Első szerző:	Prokisch József (vegyész)
Cím:	Determination of Optimal Sample Volume for Liquid Chromatograph Atomic Absorption or Emission Spectrometer Hyphenated Systems / József Prokisch, Béla Kovács, Zoltán Győri
Dátum:	1996
ISSN:	0026-265X
Tárgyszavak:	Agrártudományok Élelmiszertudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk spectrometer hyphenated
Megjelenés:	Microchemical Journal. - 54 (1996), p. 204-209. -
További szerzők:	Kovács Béla (1963-) (okleveles vegyész, angol szakfordító) Győri Zoltán (1948-) (vegyész)
Internet cím:	Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon: