CCL

Összesen 5 találat.
#/oldal:
Részletezés:
Rendezés:

1.

001-es BibID:BIBFORM002998
Első szerző:Andruch, Vasil
Cím:Investigation of the acid-base properties of 2-[2-(4-methoxy-phenylamino)-vinyl]-1,3,3-trimethyl-3H-indolium reagent / Vasil Andruch, Ioseph S. Balogh, Yaroslav R. Bazel, Ferenc Billes, Mihály Kádár, Roland Karosi, Gyula Parlagh, József Posta, András Simon, Rastislav Serbin, Marcel Torok
Dátum:2007
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Acta Chimica Slovenica. - 54 : 3 (2007), p. 551-557. -
További szerzők:Balogh Ioseph S. Bazel, Yaroslav R. Billes Ferenc Kádár Mihály Karosi Roland (1981-) (környezettudós) Parlagh Gyula Posta József (1948-) (vegyész, analitikus) Simon András Serbin, Rastislav Torok Marcel
Internet cím:elektronikus változat
elektronikus változat
Borító:

2.

001-es BibID:BIBFORM094364
Első szerző:Balogh Ioseph S.
Cím:A simple method of boron determination in mineral waters using Victoria blue 4R / Ioseph S. Balogh, Vasil Andruch, Mihály Kádár, Ferenc Billes, József Posta, Eva Szabová
Dátum:2009
ISSN:0306-7319
Megjegyzések:The reaction of the tetrafluoroborate anion with Victoria blue 4R (VB4R) reagent was investigated, and a new, simple, rapid and sensitive method was developed for the spectrophotometric determination of boron. The method is based on the reaction of boric acid with fluoride, which forms the tetrafluoroborate anion, and that is followed by the extraction of [image omitted] with VB4R into benzene and subsequent spectrophotometric detection. The optimum conditions for the conversion of boron to tetrafluoroborate anion as well as for complex formation and extraction of [image omitted] with VB4R were found. The molar absorptivity of the investigated complex is 9.6 104 L mol-1 cm-1 at 610 nm. The absorbance of the coloured extracts obeys Beer's law in the range 0.03-0.55 mg L-1 of B(III). The limit of detection calculated from a blank test (n = 10; P = 0.95) based on 3 s is 0.02 mg L-1 of B(III). Under appropriate extraction conditions, the majority of metals (excluding probably tantalum and some others) did not form extractable fluoride complexes with VB4R. Therefore, the presence of small quantities of metals should not interfere with the determination of boron in the presence of a sufficient surplus of fluoride. Exceptions, however, are metal ions such as Sn(IV), Ti(IV), Sn(II), Zr(IV), Hg(II), Hg(I), Tl(I), etc., which strongly hydrolysed under experimental conditions. Some anions formed complexes with the cation of VB4R and are easily extractable using benzene. Examples of such ions are [image omitted], I-, SCN-, Br-, bromate, chlorate, iodate and perrhenate. These anions strongly interfere with boron determination and therefore must first be extracted with VB4R before boron determination. The boron must then be converted to [image omitted] and extracted with VB4R into benzene for determination. The Cl-, [image omitted], [image omitted], CH3COO- and [image omitted] anions are extracted in very small amounts or not at all, and do not interfere with boron determination. The reaction mechanism was also discussed. Quantum chemical calculations were carried out for VB4R, and the optimised molecular structure and atomic net charges were calculated. The possible position of the protonation of VB4R as well as the possible position for dipole-ion interaction (associate building) between the reagent and the [image omitted] anion was predicted. The method was used for the determination of boron in commercial brand mineral waters.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
boron
determination
mineral waters
Victoria blue 4R
spectrophotometry
Megjelenés:International Journal of Environmental Analytical Chemistry. - 89 : 6 (2009), p. 449-459. -
További szerzők:Andruch, Vasil Kádár Mihály Billes Ferenc Posta József (1948-) (vegyész, analitikus) Szabová, Eva
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

3.

001-es BibID:BIBFORM095796
Első szerző:Karosi Roland (környezettudós)
Cím:Separation of chromium (VI) using complexation and its determination with GFAAS / Roland Karosi, Vasil Andruch, József Posta, József Balogh
Dátum:2006
ISSN:0026-265X
Megjegyzések:In acidic medium and in the presence of chloride ions 2-[2-(4-methoxy-phenylamino)-vinyl]-1,3,3-trimethyl-3H-indolium chloride forms complex with Cr(VI). The optimum conditions (pH, concentration of Cl - and the complex forming reagent) of the separation and extraction of Cr(VI) into toluene using this basic dye as a complexing reagent have been determined and the possible interferences of Ca, Mg, Na, K, Cr(III), Ni, Pb, Hg, Mn, Al, Cu have been studied. An electrothermal atomic absorption spectrometer (GFAAS) was used for the determination of Cr(VI). The detection limit of the method for Cr(VI) found to be 0.15 ?g dm ? 3 and RSD for spiked drinking water was better than 3%.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Speciation
Chromium
Extraction
GFAAS
Megjelenés:Microchemical Journal. - 82 : 1 (2006), p. 61-65. -
További szerzők:Andruch, Vasil Posta József (1948-) (vegyész, analitikus) Balogh József
Pályázati támogatás:T043366
OTKA
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

4.

001-es BibID:BIBFORM100905
035-os BibID:(cikkazonosító)2361
Első szerző:Karosi Roland (környezettudós)
Cím:Using dimethyl indocarbocyanide (DIC) as ion-pair agent for chromium speciation and its application in GFAAS analysis of water / Karosi Roland, Boruzs Klára, Béni Áron, Posta József, Balogh József, Andruch Vasil
Dátum:2012
ISSN:1759-9660 1759-9679
Megjegyzések:A novel procedure for the determination of Cr(VI) using electrothermal atomic absorption spectrometry with Zeeman background correction was developed. The method is based on the reaction of Cr(VI) with dimethyl indocarbocyanine (DIC) in acidic medium in the presence of chloride ion followed by liquid?liquid extraction of the ion associate formed and subsequent GFAAS detection. The optimum conditions (pH, concentrations of chloride ion and DIC) were determined for the extraction of Cr(VI) into toluene. Furthermore, the effect of temperature on the separation, the stability of the complex formed, possibilities of preconcentration and possible interference of Fe, Cd, Co, Ba, Al, Hg, Zn, Ni, Cu, V, Mn and Pb were studied as well. The detection limit (LOD) of the method for Cr(VI) was found to be 0.25 ?g L?1 and RSD was mostly better than 5% using a 1?:?1 ratio for the organic and water phases.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
elemental speciation
Megjelenés:Analytical Methods. - 4 : 8 (2012), p. 1-4. -
További szerzők:Boruzs Klára (1983-) (környezetkutató vegyész és MBA) Béni Áron (1978-) (vegyész) Posta József (1948-) (vegyész, analitikus) Balogh József Andruch, Vasil
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

5.

001-es BibID:BIBFORM016471
Első szerző:Kocúrová, Lívia
Cím:A novel approach in dispersive liquid-liquid microextraction based on the use of an auxiliary solvent for adjustment of density UV-VIS spectrophotometric and graphite furnace atomic absorption spectrometric determination of gold based on ion pair formation / Lívia Kocúrová, Ioseph S. Balogh, Jana Škrlíková, József Posta, Vasil Andruch
Dátum:2010
ISSN:0039-9140
Megjegyzések:This paper presents a novel approach to dispersive liquid-liquid microextraction (DLLME), based on the use of an auxiliary solvent for the adjustment of density. The procedure utilises a solvent system consisting of a dispersive solvent, an extraction solvent and an auxiliary solvent, which allows for the use of solvents having a density lower than that of water as an extraction solvent while preserving simple phase separation by centrifugation. The suggested approach could be an alternative to procedures described in the literature in recent months and which have been devoted to solving the same problem. The efficiency of the suggested approach is demonstrated through the determination of gold based on the formation of the ion pair [Au(CN)(2)](-) anion with Astra Phloxine (R) reagent and its extraction using the DLLME procedure with subsequent UV-VIS spectrophotometric and graphite furnace atomic absorption spectrometric detection. The optimum conditions were found to be: pH 3; 0.8 mmol L-1 K-4[Fe(CN)(6)]; 0.12 mmol L-1 R; dispersive solvent, methanol; extraction solvent, toluene; auxiliary solvent, tetrachloromethane. The calibration plots were linear in the ranges 0.39-4.7 mg L-1 and 0.5-39.4 mu g L-1 for UV-VIS and GFAAS detection, respectively; thus enables the application of the developed method in two ranges differing from one from another by three orders of magnitude. The presented approach can be applied to the development of DLLME procedures for the determination of other compounds extractable by organic solvents with a density lower than that of water. (C) 2010 Elsevier B.V. All rights reserved.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Dispersive liquid-liquid microextraction
Auxiliary solvent
Ion pair
Gold
UV-VIS spectrophotometry
Graphite furnace atomic absorption
spectrometry
mass-spectrometry
water samples
Megjelenés:Talanta (Oxford). - 82 : 5 (2010), p. 1958-1964. -
További szerzők:Balogh Ioseph S. Škrlíková, Jana Posta József (1948-) (vegyész, analitikus) Andruch, Vasil
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Rekordok letöltése1 
Corvina könyvtári katalógus v8.2.27 © 2023 Monguz kft. Minden jog fenntartva.