Gubbuk I.H.,Selcuk University
Journal of Hazardous Materials | Year: 2011
In this study, sporopollenin of Lycopodium clavatum spores was used for the sorption experiment. Glutaraldehyde (GA) immobilized sporopollenin (Sp), is employed as a sorbent in sorption of selected heavy metal ions. The sorbent prepared by sequential treatment of sporopollenin by silanazing compound and glutaraldehyde is suggested for sorption of Cu(II), Zn(II) and Co(II) from aqueous solutions. Experimental conditions for effective sorption of heavy metal ions were optimized with respect to different experimental parameters using batch method in detail. Optimum pH range of Cu(II) has occurred at pH≥5.5 and Zn(II), Co(II) at pH≥5.0, for the batch method. All of the metal ions can be desorbed with 10cm3 of 0.5moldm-3 of ethylenediaminetetraacetic acid (EDTA) solution. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm equations were applied to the experimental data. Thermodynamic parameters such as free energy (ΔGo), entropy (ΔSo) and enthalpy (ΔHo) were also calculated from the sorption results used to explain the mechanism of the sorption. The results indicated that this sorbent is successfully employed in the separation of trace Cu(II), Zn(II) and Co(II) from the aqueous solutions. © 2010 Elsevier B.V.
Malkondu S.,Selcuk University
Tetrahedron | Year: 2014
A novel 'turn-on' fluorescent probe with perylene tetracarboxylic bisimide (PBI) as the fluorophore and di(2-(salicylideneamino))ethylamine (DSEA) as the metal ion receptor was designed. The capability of the prepared probe to detect metal ions was evaluated by the changes in its emission intensity. The probe demonstrated a considerable emission enhancement (ca. 110-fold) in the presence of Al3+in MeCN with high selectivity and sensitivity. Furthermore, the considerably 'off-on' fluorescence response concomitantly led to the apparent color change from colorless to brilliant yellow, which could also be identified by naked eye easily under UV lamp. © 2014 Elsevier Ltd. All rights reserved.
Mulazimoglu I.E.,Selcuk University
Energy Education Science and Technology Part A: Energy Science and Research | Year: 2011
In this paper, a simple and sensitive method for the electrochemical determination of phenol in soil sample using disposable screen-printed glassy carbon (GC) electrode surface modified with an electrografted aminophenol film, via the electrochemical reduction of its prepared aminophenol diazonium salt in non-aqueous media, is presented. 1 mM of aminophenol diazonium salt (APDAS) in 100 mM tetrabutylammonium tetrafluoroborate (TBATFB) was used for modification of GC electrode surface in this study. The surface modification of GC electrode was performed with aminophenol (AP) using cyclic voltammetry (CV), whereas the characterization of this sensor electrode was performed using CV and electrochemical impedance spectroscopy. The modification process was carried out in non-aqueous media, whereas phenol determination was carried out in aqueous media. Acetonitrile (MeCN) for providing non-aqueous condition and Britton-Robinson (BR) buffer solution at pH 10 and 100 mM KCl solution for providing aqueous condition were used. As the final of this study, a reaction mechanism was suggested for the binding of phenol to aminophenol modified GC electrode surface. 0.1316 mgL -1 phenol was determined in soil sample by using AP modified GC electrode. © Sila Science.
Uyan M.,Selcuk University
Renewable and Sustainable Energy Reviews | Year: 2013
Renewable energy is clean sources and has a much lower environmental impact than other energy sources. In Turkey, solar energy investments have been developed rapidly in recent years. Site selection for solar farms is a critical issue for large investments because of quality of terrain, local weathering factors, proximity to high transmission capacity lines, agricultural facilities and environmental conservation issues. Multi criteria evaluation methods are often used for different site selection studies. The purpose of this study was to determine suitable site selection for solar farms by using GIS and AHP in the study area. The final index model was grouped into four categories as "low suitable", "moderate", "suitable" and "best suitable" with an equal interval classification method. As a result, 15.38% (928.18 km2) of the study area has low suitable, 14.38% (867.83 km2) has moderate suitable, 15.98% (964.39 km2) has suitable and 13.92% (840.07 km2) has best suitable for solar farms area. 40.34% (2434.52 km2) of the study area is not suitable for solar farm areas. © 2013 Elsevier Ltd.
Ozcan S.,Selcuk University
Journal of Separation Science | Year: 2011
A method was developed for viable and rapid determination of seven polychlorinated biphenyls (PCBs) in water samples with vortex-assisted liquid-liquid microextraction (VALLME) using gas chromatography-mass spectrometry (GC-MS). At first, the most suitable extraction solvent and extraction solvent volume were determined. Later, the parameters affecting the extraction efficiency such as vortex extraction time, rotational speed of the vortex, and ionic strength of the sample were optimized by using a 23 factorial experimental design. The optimized extraction conditions for 5 mL water sample were as follows: extractant solvent 200 μL of chloroform; vortex extraction time of 2 min at 3000 rpm; centrifugation 5 min at 4000 rpm, and no ionic strength. Under the optimum condition, limits of detection (LOD) ranged from 0.36 to 0.73 ng/L. Mean recoveries of PCBs from fortified water samples are 96% for three different fortification levels and RSDs of the recoveries are below 5%. The developed procedure was successfully applied to the determination of PCBs in real water and wastewater samples such as tap, well, surface, bottled waters, and municipal, treated municipal, and industrial wastewaters. The performance of the proposed method was compared with traditional liquid-liquid extraction (LLE) of real water samples and the results show that efficiency of proposed method is comparable to the LLE. However, the proposed method offers several advantages, i.e. reducing sample requirement for measurement of target compounds, less solvent consumption, and reducing the costs associated with solvent purchase and waste disposal. It is also viable, rapid, and easy to use for the analyses of PCBs in water samples by using GC-MS. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.