Browsing by Author "Gürkan R."
Now showing items 21-40 of 69
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Development of a new analytical methodology based on the catalytic effect of AG(I) in a new fuchsin-peroxodisulfate-1,10-phenantroline system: Application to the determination of trace amounts of silver
Gürkan R.; Ulusoy H.I. (2014)A simple, rapid and sensitive kinetic spectrophotometric method is proposed for the determination of trace amounts of silver ion in the concentration ranges of 2-20 and 20-50 ?g L-1. The proposed method is based on the ... -
Development of a New Methodology for Indirect Determination of Nitrite, Nitrate, and Total Nitrite in the Selected Two Groups of Foods by Spectrophotometry
Altunay N.; Gürkan R.; Olgaç E. (Springer New York LLC, 2017)A new indirect preconcentration procedure was developed for micellar sensitive detection of trace nitrite as analyte by spectrophotometry. The method is based on ion association of triiodide ion, I3 ? or I2, produced by ... -
Development of a simple, sensitive and inexpensive ion-pairing cloud point extraction approach for the determination of trace inorganic arsenic species in spring water, beverage and rice samples by UV-Vis spectrophotometry
Gürkan R.; Kir U.; Altunay N. (2015)The determination of inorganic arsenic species in water, beverages and foods become crucial in recent years, because arsenic species are considered carcinogenic and found at high concentrations in the samples. This ... -
Development of an inexpensive and sensitive method for the determination of low quantity of arsenic species in water samples by CPE-FAAS
Ulusoy H.B.; Akay M.; Gürkan R. (2011)The simple and rapid preconcentration technique using cloud point extraction (CPE) was applied for the determination of As(V) and total inorganic arsenic (As(V) plus As(III)) in water samples by means of FAAS. As(V) has ... -
Evaluation of the thermodynamic parameters for the adsorption of some hydrocarbons on chemically treated-bentonites by inverse gas chromatography
Gürkan R.; Ceylan H.; Şahan T.; Savran A.; Kubilay Ş. (2005)Inverse gas chromatography has been used to evaluate the adsorption parameters (?H a, ?H st, ?S a and ?G a) of some probe molecules, each representing a class of organic (n-hexane, cyclohexane, benzene, n-octane, 1-octene ... -
Extraction, preconcentration and spectrophotometric determination of trace levels of thiosulfate in environmental waters
Gürkan R.; Altunay N.; Gürkan N. (Springer Verlag, 2017)In the existing study, a new vortex-assisted cloud point extraction (VA-CPE) method was developed for determination of low levels of thiosulfate in environmental waters at 632 nm by spectrophotometry. The method is selectively ... -
Extraction, Preconcentration, and Quantification of Low Levels of Free Formaldehyde from Some Beverage Matrices by Combination of Ultrasound-Assisted-Cloud Point Extraction with Spectrophotometry
Temel N.K.; Gürkan R. (Springer New York LLC, 2017)In the present study, due to use of formaldehyde (FA) as a food additive as well as its endogenous and natural occurrence in aquatic products, a new preconcentration method for the quantification of free formaldehyde (FA) ... -
A fast and reliable method for quantitative determination of total mercury in vegetables
A cloud-point extraction (CPE) process using the nonionic surfactant, polyethylene glycol tert octylphenyl ether (Triton X-114) was employed for determination of Hg(II) ions in aqueous solutions. The method is based on the ... -
Indirect Determination of Free, Total, and Reversibly Bound Sulfite in Selected Beverages by Spectrophotometry Using Ultrasonic-Assisted Cloud Point Extraction as a Preconcentration Step
Altunay N.; Gürkan R.; Sertakan K. (2015)A new indirect ultrasonic-assisted cloud point extraction (UA-CPE) method has been developed for the determination of trace sulfite species by means of spectrophotometry. The method is based on either directly imide–bisulfite ... -
Indirect quantification of trace levels cyanide in environmental waters through flame atomic absorption spectrometry coupled with cloud point extraction
Cloud point extraction (CPE) has been used for the preconcentration and indirect quantification of cyanide after the formation of a ion-associate complex with 3-amino-7-diethylamino-8,9-benzo-2-phenoxazine chloride (Nile ... -
An Inexpensive and Sensitive Method for Speciative Determination of Sn(IV), Sn(II), and Total Sn as Sn(IV) in Selected Beverages by Micellar Improved Spectrophotometry
Altunay N.; Gürkan R. (2015)In the present study, an inexpensive, selective, and micellar sensitive spectrophotometric method for Sn(IV) was developed at 537 nm. The method is based on the formation of ternary complex of Sn(IV) with tartaric acid and ... -
Inexpensive and versatile method for trace Sn(II) and Sn(IV) ions in food samples by CPE/FAAS
Ulusoy S.; Ulusoy H.I.; Akçay M.; Gürkan R. (2012)In this work, a new cloud point extraction procedure was developed for the separation and preconcentration of tin ions in water and food samples. The method is based on the complexation of Sn(IV) ions with calcon carboxylic ... -
The investigation of a novel indicator system for trace determination and speciation of selenium in natural water samples by kinetic spectrophotometric detection
Gürkan R.; Ulusoy H.I. (2010)A novel catalytic kinetic method is proposed for the determination of Se(IV), Se(VI) and total inorganic selenium in water based on the catalytic effect of Se(IV) on the reduction of bromate by p-nitrophenylhydrazine at ... -
Investigation of Pd-catalyzed Co(III)-EDTA/hypophosphite inhibition reaction kinetics, mechanism and the evaluation of its analytical application possibilities
Biçer N.; Gürkan R.; Akçay M.; Altunata T. (Serbian Chemical Society, 2004)The reaction between Co(III)-EDTA and hypophosphite ion, catalyzed by Pd(II) was chosen as the indicator reaction. The inhibition kinetics of this catalytic reaction have been investigated by a mechanistic approach in the ... -
Investigation of separation and identification possibilities of some metal-DEDTC complexes by sequential TLC-IR system
Gürkan R.; Savasci S. (Preston Publications, 2005)The separation and identification possibilities of some metal-diethyldithiocarbamate (DEDTC) complexes are investigated by thin-layer chromatography-IR sequential system. DEDTC complexes of metal cations are prepared in a ... -
Investigation of separation and indentification possibilities of some metal-dithizonate complexes by sequential TLC-IR system
Gürkan R.; Savaşci Ş.; Ozkan M.H.; Akçay M. (2005)The separation and identification possibilities of a number of metal-dithizonate complexes were investigated by means of a TLC-IR sequential system. Dithizonate complexes of some metal cations were pre-pared in a predetermined ... -
Kinetic spectrophotometric determination of trace amounts of selenium based on the catalytic reduction of maxilon blue-SG by sulfide
A simple and sensitive catalytic spectrophotometric method was developed for the determination of trace amounts of selenium. The method is based on the catalytic effect of selenium in form Se(IV) on the reduction of Maxilon ... -
Kinetic spectrophotometric determination of trace copper(II) ions by their catalytic effect on the reduction of brilliant cresyl blue by ascorbic acid
Ulusoy H.I.; Gürkan R.; Akçay M. (2011)In the present study, a novel catalytic-kinetic spectrophotometric method was developed for the determination of trace amounts of copper. It is based on the catalytic effect of Cu(II) on the reduction of brilliant cresyl ... -
Manganese sensitised-indirect determination of melamine in milk-based samples by flame atomic absorption spectrometry coupled with ultrasound assisted-cloud point extraction
Gürkan R.; Kartal Temel N. (Taylor and Francis Ltd., 2019)In the current study, a simple and low- cost method of UA-CPE in combination with flame atomic absorption spectrometry (FAAS) was developed for pre-concentration and indirect determination of melamine in milk-based samples. ... -
Micellar sensitized catalytic kinetic spectrophotometry for highly accurate and reproducible determination of V(IV) and V(V)
Gürkan R.; Emektaş C. (2014)A highly accurate and reproducible micellar sensitized kinetic method was proposed for determination of V(VI). The method is based on its catalytic effect on the oxidation of Coomassie brilliant blue R 250 (CBB+) by bromate ...