GCRIS

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Citation - WoS: 8
Hydrogen Sulfide Determination by Solid Surface Luminescence
(Springer Verlag, 1996) Eroğlu, Ahmet Emin; Volkan, Mürvet; Bayramlı, Erdal; Ataman, O. Yavuz; Mark, Harry B.
In the analytical system suggested, atmospheric hydrogen sulfide reacts with the surface of a filter paper treated with aqueous cadmium chloride and yields a luminescent species whose intensity can be correlated with the analyte concentration in ambient air. It was shown that the luminescent species are CdS solid particles which were formed in a well defined size. The paper luminescence was also tried on polymeric surfaces; polyethyleneoxide, polyvinyl alcohol, ethylcellulose and carboxymethylcellulose were found to give a similar luminescence signal. The system can be used on the tip of an optical fiber for an irreversible, cumulative type of analytical device for hydrogen sulfide determination. The 3s detection limit for the paper luminescence detection system was 7.8 ppb H2S.
Citation - WoS: 24
Fiber Optic Sensors Using Novel Substrates for Hydrogen Sulfide Determination by Solid Surface Fluorescence
(Elsevier Ltd., 2000) Eroğlu, Ahmet Emin; Volkan, Mürvet; Ataman, O. Yavuz
Two different fiber optic sensors were developed for the determination of hydrogen sulfide at ppb concentration levels; a probe-type fiber optic sensor coated with polyethylene oxide containing 0.5 M CdCl2 and a fiber optic sensor utilizing 0.5 M CdCl2-pretreated filter paper as solid substrate. In the first type, CdCl2–polyethyleneoxide (PEO) mixture was coated onto the tip of a fiber optic probe and the probe was exposed to H2S. The methodology is based on the measurement of CdS fluorescence on the surface. Detection limit (3s) of the PEO-coated fiber optic system was 36.0 ppb for H2S and precision at the 0.552 ppm level was 29% R.S.D. For the fiber optic system utilizing CdCl2-pretreated filter paper, two different configurations were devised and evaluated; a bifurcated fiber optic sensor and a single fiber optic sensor. Similar figures were obtained with these two systems; the detection limit (3s) was 4.0 ppb for the bifurcated fiber optic sensor and 4.3 ppb for the single fiber optic sensor, and both sensors had linear responses in the range 0.032–1.0 ppm. Their precisions at 0.299 ppm level were also very similar, 10 and 11% R.S.D., respectively, for the bifurcated and single fiber systems. In addition to the fiber optic sensors developed, various surfactants (sodiumdodecylsulfate (SDS), Aerosol OT, Aerosol A102, Aerosol 501), some cellulosic substances (sodium carboxymethylcellulose (CMC), ethylcellulose, hydroxypropylmethylcellulose, ethylhydroxyethylcellulose, α-cellulose) and several water-soluble polymers (polyacrylicacid polyethleneoxide (PEO), polyvinylalcohol (PVA)) were dissolved in proper solvents and after mixing with 0.5 M CdCl2, were spread over glass slides. These novel solid substrates were exposed to H2S and fluorescence signal on the surfaces of the glass slides was measured with a luminescence spectrometer. The new substrates were shown to be good alternatives to filter paper for the determination of H2S by room temperature solid surface fluorescence spectrometry.
Citation - WoS: 9
A novel sorbent tube for ambient hydrogen sulfide determination
(Elsevier Ltd., 1998) Eroğlu, Ahmet Emin; Volkan, Mürvet; Eroğlu, Tijen; Ataman, O. Yavuz; Mark, Harry B.
A novel tubular device has been developed for hydrogen sulfide determination in air. Several substrates such as commercial silica gel and alumina TLC plates, silica gel powder, alumina, CaSO4, CaCO3, BaSO4, MgO, chalk, α-cellulose and ethyl cellulose were tested as solid substrates. 30–70-mesh silica gel was finally employed in glass tubes of 4.0 mm internal diameter. Silica gel is treated with 0.5 M aqueous CdCl2 solution, dried, filled into the glass tube and sample gas is passed through the device using nitrogen as the carrier gas where 70% relative humidity is employed. The analyte reacts with the solid substrate to form a luminescent spot whose length in the tube is measured and correlated to concentration. The flow rate was 68 ml min−1. The analytical system is linear in the range of 0.2–1.3 ppm H2S for the specified conditions. The prepared devices are stable at least for 3 months prior to sampling; and after sampling, the luminescing spot is stable also at least for 3 months.
Citation - WoS: 31
Citation - Scopus: 32
Speciation and Preconcentration of Inorganic Tellurium From Waters Using a Mercaptosilica Microcolumn and Determination by Hydride Generation Atomic Absorption Spectrometry
(Royal Society of Chemistry, 2000) Körez, Aslıhan; Eroğlu, Ahmet Emin; Volkan, Mürvet; Ataman, O. Yavuz
A separation–preconcentration method utilising a mercapto-modified silica microcolumn was developed for the determination of trace amounts of Te(IV) and Te(VI) in waters by hydride generation atomic absorption spectrometry. Bottled drinking water, tap water and sea-water samples were spiked with sub-ng ml−1 concentrations of Te(IV) and the spiked solutions were subjected to the mercapto-modified silica microcolumn separation and enrichment procedure. The spike recovery values varied between 86 and 114%. In addition to spike recovery experiments, accuracy was also verified via the analysis of a certified reference material. The limit of detection for Te(IV) in sea-water with a preconcentration factor of 50 was 0.037 ng ml−1. The capability of the microcolumn enrichment scheme for on-line sample processing via flow manifolds was demonstrated. A detailed interference study was performed.

Chemistry / Kimya

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