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Öğe Comparison of Extraction Procedures for Assessing Soil Metal Bioavailability of to Wheat Grains(Wiley, 2011) Bakircioglu, Dilek; Kurtulus, Yasemin Bakircioglu; Ibar, HilmiAgricultural soils have been analyzed to elucidate whether the trace metal distribution changes in relation to agricultural activities and to predict environmental risk. In addition to the extractability of Cu, Mn, Ni, Pb, and Zn in soils was compared by single extraction (hydrochloric acid (HCl), ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), calcium chloride (CaCl2), water (H2O)), and sequential extraction procedures. The modified Community Bureau of Reference (BCR) sequential extraction procedure (three-step) used to extraction of metals in soil samples. The extraction capacity of the analyzed metals was found by using single extraction procedures in the order: HCl > EDTA > DTPA > CaCl2 > H2O. A single correlation analysis was used to investigate the relationship between extractable metal concentrations in soil solutions and metal accumulation in wheat grains. Simple correlation analyses indicated that the extractable Pb and Ni of soils by HCl, EDTA, and DTPA single extraction procedures were significantly correlated with the metal contents of wheat grains. For CaCl2, H2O, and BCR extraction procedures there was a relatively poor correlation between the extractable Cu, Mn, Ni, Pb, and Zn of soils and metal contents of wheat grains.Öğe Determination of Cd, Mn, Sb, Ni and Fe in water samples after preconcentration on bentonite modified with trioctyl phosphine oxide(Parlar Scientific Publications (P S P), 2007) Aktas, Yildiz Kalebasi; Ibar, HilmiBentonite modified by the addition of trioctyl phosphine oxide (TO-B) is developed for the separation and preconcentration of Cd, Mn, Sb, Ni and Fe, prior to their determination by flame atomic absorption spectrometry (FAAS). Separation and preconcentration of the above metals have been investigated by a column method using, TO-B as adsorbent, and analytes were quantitatively retained at pH 6.0. The elements collected were completely recovered with 1 mol/L of nitric acid. Low blank values of the collector have served as important advantage, and recoveries were 98.3%, 98.6%, 100%, 98.1% and 100% for Cd, Mn, Sb, Ni and Fe, respectively. The relative standard deviations were found to be 1.0-4.0%. Detection limits (3 sigma) were 0.25 mu g L-1 for Cd, 0.19 mu g L-1 for Mn, 2.3 mu g L-1 for Sb, 0.17 mu g L-1 for Ni and 0.12 mu g L-1 for Fe. The method was practically applied analysing the studied elements in wastewaters. The method can be characterized with fastness, simplicity, quantitative recovery, and high reproducibility.Öğe The Determination of Single and Mixture Toxicity at High Concentrations of Some Acidic Pharmaceuticals via Aliivibrio fischeri(Springer International Publishing Ag, 2014) Dokmeci, Ayse Handan; Dokmeci, Ismet; Ibar, HilmiPharmaceutical and Personal Care Products (PPCPs) may cause serious and significant environmental pollution. Environmental analyses have detected pharmaceuticals in addition to conventional chemical pollutants. In our study, the acute toxicity of ibuprofen, naproxen, diclofenac, salicylic acid and substances that are mixtures themselves (INDS) on Aliivibrio fischeri bacterium were assessed with the use of ToxAlert (R). The selected materials are acidic in nature, highly polarized and widely sold over-the-counter analgesics. Dose-response curves were drawn, and linear regression analyses and probit analyses determined their 50 %-effective concentrations (EC50). The pharmaceuticals alone are unlikely to have acute impacts in aquatic environments. However, when evaluated in combination with A. fischeri bacterium, the acute toxicity of the INDS mixture was EC50 7.09 +/- 5.1 mg/L and the acute toxicity of TUs was 14.10, which indicates their very toxic quality for organisms. Since the target components do not exist in isolation, we should primarily consider the toxicity of the mixture only at high concentrations.Öğe Development of spectrophotometric determination method for Au(III) and Ag(I)(Marmara Univ, Fac Pharmacy, 2017) Erdogan, Gulbin; Dolen, Emre; Ibar, HilmiIn this research, a potentiometric and spectrophotometric method was developed to determine Ag(I) and Au(III) based on their reaction with m and p-phenylenediamine. As a result reactions between Ag(I) and Au(III) and m-and p-phenylenediamine mixtures was revealed that, there is an oxidation by means of complexation via oxidation, a diazo compound occured from amines and Ag(I) was reducted to elementel form, Au(III) was reducted to Au(I). Also the formation conditions of the reactions of these metals with amines were investigated, the pH range that the reactions took place, time needed for the formation of the reactions and the mol ratios needed for the complete reaction of the metals with amines. Mole ratios were determined as follows: Ag(I) / (m+p) phenylenediamine= 1; Au(III) / (m+p) phenylenediamine= 1/2Öğe Effective one-step microwave extraction of PCB congeners from soil followed by GC-MS analysis(Amer Chemical Soc, 2014) Ibar, Hilmi[Abstract Not Available]Öğe Extraction of iron(III), antimony(III) and cadmium(II) from hydrochloric acid by trioctyl amine and trioctyl phosphine oxide in isoamyl acetate(Parlar Scientific Publications (P S P), 2007) Aktas, Yildiz Kalebasi; Ibar, HilmiThe extraction of iron (III), antimony (III) and cadmium (II) from hydrochloric acid solutions has been investigated using high-molecular weight amine (trioctyl amine, TOA, R3N) and a neutral organophosphorus compound (trioctyl phosphine oxide, TOPO) in isoamyl acetate (IAA). It was found that the efficiency of batch extraction method for the studied elements is almost similar for trioctyl phosphine oxide and trioctyl amine, both at low and higher acidity. This method was applied to the analysis of the elements in wastewaters. In addition, the back-extractions for iron, antimony and cadmium were studied. The interfering effects of sodium, potassium, magnesium, calcium, lead and cobalt were investigated. Blank values were low and recoveries were 100%, 100% and 88.3% for iron, antimony and cadmium, respectively, at 95% confidence level. The relative standard deviations for the determinations were found to be 1.0-6.0%. Detection limits (3 sigma) were 0.5 mu g L-1 for iron, 0.6 mu g L-1 for antimony and 2.9 mu g L-1 for cadmium.Öğe Investigation of trace elements in agricultural soils by BCR sequential extraction method and its transfer to wheat plants(Springer, 2011) Bakircioglu, Dilek; Kurtulus, Yasemin Bakircioglu; Ibar, HilmiIn this study, soil samples were collected from Edirne, Turkey in both summer and winter seasons and subjected to the modified Community Bureau of Reference (BCR) sequential extraction procedure in order to investigate the chemical partitioning of metals in soils and to predict heavy metals uptake by wheat grains which grown at the same soils. The samples were subjected to a three stage extraction procedure proposed by the BCR. The three phases that were separated out in the following order: (1) carbonate, exchangeable, (2) Fe-Mn oxides, and (3) organic matter. Metal concentrations of soil fractions and grain samples were determined by inductively coupled plasma atomic emission spectroscopy. The wheat samples were prepared to analysis using microwave acid digestion procedure. The pseudo-total concentrations of metals were determined after aqua regia digestion. The analytical accuracy of the method was evaluated by using the Standard Reference Materials (BCR 142R Light Sandy Soil, NIST 2711 Montana Soil, and NIST 2704 Buffalo River Sediment). The sum of the metal contents obtained from the modified BCR sequential extraction procedure and pseudo-total metal contents for soil samples were used to calculate recovery values. In order to evaluate the bioavailability of metals, the relationships between the wheat-metal and soil-extractable metal concentrations were compared.
