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Öğe Basic nutrients and element contents of white cheese of diyarbakir in turkey(Elsevier Sci Ltd, 2004) Merdivan, M; Yilmaz, E; Hamamci, C; Aygun, RSBasic nutrients, moisture, fat and protein, and concentrations of 15 major and trace elements in total and fatty parts of Diyarbakir white cheese were evaluated for compositional differences. Elements were determined using inductively coupled plasma atomic emission spectrometry, while fat was determined by supercritical extraction and protein by protein/nitrogen analyzer. Diyarbakir brine and melt cheeses have lower humidity and higher protein than market brine cheese samples. The fat level was 14-18% for all cheeses. The levels of investigated major and trace elements were much higher in three types of cheese samples. Except for Zn and Mn, the other investigated elements were found in fairly low concentrations and at variable ranges in the fatty part of cheese samples. The elements, Mg among major elements and Fe among trace elements, were highest in that part. Na and Ca as major and Zn, Fe and Al as trace elements were found at maximum levels, especially in Diyarbakir melt cheese. Also, levels correlations between basic nutrients, basic nutrients and elements and element pairs were investigated. (C) 2003 Published by Elsevier Ltd.Öğe Chemical analysis of geothermal water of Cermik, Turkey(Parlar Scientific Publications (P S P), 2003) Akba, O; Baysal, A; Hamamci, C; Merdivan, M; Gumgum, BGeothermal water of Cermik, which is located in Southeast Anatolia - Turkey, is a Na-Cl-HCO3 type containing also sulfide and iodide. The temperature, pH and flow rate of the geothermal water are 51 degreesC, 7.6 and 21 L s(-1), respectively. Its physical and chemical characterization in detail was done using standard methods. The trace elements Al, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn were analyzed directly using inductively coupled plasma-atomic emission spectrometry due to very low detection limits and the good reproducibility of this analytical method.Öğe Comparison of microwave digestion procedures for the determination of some elements in asphaltite ash using ICP-AES(Soc Chimica Italiana, 2002) Baysal, A; Akba, O; Merdivan, M; Hamamci, C; Gümgüm, BA microwave digestion procedure for asphaltite ash was developed in an attempt to facilitate routine analysis and obtain reproducible conditions or comparable results. The. conditions of the most effective procedure for 0.1g asphaltite ash samples are 1 ml of HNO3 + 3 ml of HCl + 1 ml of HF + 1 ml of deionized water as acid mixture and 15 min for digestion time. The digestion was accomplished in five stages applying continuously 90 % to 20 % of the microwave power and 20 to 100 psi of the pressure for 10 min of total time. Concentrations of selected elements, Cr, Co, Fe, Mn, Ni and Zn were measured using inductively coupled plasma-atomic emission spectroscopy. The proposed method of digestion provided precise results with relative standard deviations generally less than 3 % for investigated elements. Results for fly ash as standard reference material was in good agreement with certified values.Öğe Desulfurization of southeastern Anatolian asphaltites by the Meyers method(Elsevier Science Bv, 1997) Hamamci, C; Kahraman, F; Duz, MZSoutheastern Anatolian asphaltites are notoriously high in sulfur and therefore not suitable for direct use in combustion without extensive cleaning. In order to remove sulfur from asphaltites collected from Sirnak and Hazro, the Meyers (Fe3- salts) method was used. The effects of ferric concentration, coal particle size, temperature and time on the extraction efficiency were investigated and the experimental results are presented here. Most of the pyritic and sulfate sulfur was eliminated from the asphaltite samples. (C) 1997 Elsevier Science B.V.Öğe Effect of structural modifications of diaza-18-crown-6 on the extractability and selectivity of univalent metal picrates(Elsevier Science Bv, 2001) Ziyadanogullari, B; Topal, G; Erdogan, S; Hamamci, C; Hosgoren, HThe solvent extraction of univalent metal cations with N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16 diaza-2,3,11,12-dibenzocycloocta deca-2,11-diene (L-1), N,N'-didodecyl-1,4,10,13-tetraoxa-7,16-diaza-2,3-benzocylooctadeca-2-ene (L-2) and N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diaza-2,3,11,12-dibenzocyclo octadeca-2,11-diene (L-3) with picrate anion into dichloromethane has been studied at 25 degreesC by UV-visible spectroscopy. The extractability and selectivity of univalent metal picrates (Li+, Na+, Ag+, PhCH2NH3+, NH4+) was evaluated as a function of [ligand]/[metal cation]. L-2 showed the highest extractability and selectivity for Lit over the larger studied cations, and also exhibited the highest [Li+]/[NH4+] selectivity as L/M = 1. (C) 2001 Elsevier Science B.V. All rights reserved.Öğe Effect of winter air pollution on lipid peroxidation product levels of patients with chronic obstructive pulmonary disease(Mrs Pushpa Agarwal, 2006) Isik, B; Hamamci, C; Isik, RAir pollution and its effects on human health have been considered to the a serious problem in urban areas. The health hazards of outdoor air pollution are manifest across a wide spectrum of effects. Patients with. respiratory disease and chronic obstructive pulmonary disease (COPD), given their abnormal responses to noxious gases and particles. The causes of oxidative stress in COPD are cigarette smoking, air pollution and increase of free radicals in respiratory epithelial cells by inflammation and infections. In the present study, we aim to investigate the effect on oxidative stress due to air pollution in patients with COPD in Diyarbakir (SE Anatolia) Turkey. Clinically stable COPD outpatients (n = 52) and healthy controls (n = 42) were studied. The lipid peroxidation product malonyldialdehyde (MDA) in serum samples was measured spectrophometrically by the Buege method. The serum MDA levels of patients with COPD (3.06 +/- 0.7 nmol/ml) were significantly higher than those of control groups (0.62 +/- 0.19 nmol/mL) (p < 0,001)Öğe Elemental composition of Southeastern Anatolia asphaltites (Turkey) as a function of particle size(Estonian Academy Publishers, 2003) Hamamci, C; Düz, MZ; Saydut, A; Merdivan, MElemental composition of asphaltites from Southeastern Anatolia was determined after grinding the samples and separating particles obtained into fractions by sieving. The total content of carbon, hydrogen, nitrogen and sulfur was highest in Halbur asphaltite where they were present over a wide size range (from 125 to 600 mum). The content of nitrogen, the least element in asphaltites, did not depend on grain size, whereas the carbon and sulfur concentrations increased with increasing size.Öğe Formation and characterization of humic acids from low rank anatolian coals by air oxidation(Taylor & Francis Inc, 2005) Erdogan, S; Duz, MZ; Merdivan, M; Hamamci, CThe results of this study are aimed at evaluating the effects of air oxidation time, temperature and demineralization on humic acid production from two low-rank Anatolian coals. Two Anatolian low rank coals were studied at 120 and 200degreesC up to 10 days with and without demineralization. The best results for humic acid formation were obtained at a high temperature for longer times. Demineralization effect is negligible for studied coals. The rate of humic acid formation increased at first with increase in oxidation time, reached a maximum, and then decreased at high oxidation time. Also, a detailed study of the elemental composition, the characterization by FTIR, and the acidity of humic acids are reported.Öğe Heroin profiling using alkaloids and metal concentrations(Elsevier Sci Ireland Ltd, 2003) Bora, T; Merdivan, M; Hamamci, C[Abstract Not Available]Öğe Lead in urban street dust in Diyarbakir, Turkey(Inst Lebensmitteltechnologie Analytische Chemie, 1997) Hamamci, C; Gumgum, B; Akba, O; Erdogan, SParticulate matters were collected from thirteen locations in and around Diyarbakir(Turkey) in September 1995 to determine lead content. Lead analyses were performed with ICP-AES measured at 266.316 nm. The average concentrations of lead in urban street dust in Diyarbakir, Turkey was found to be 911 ppm (ranging from 616 to 1208 ppm).Öğe Levels of trace and major elements in illicit heroin(Amer Soc Testing Materials, 2002) Bora, T; Merdivan, M; Hamamci, CTen elements, aluminum (Al), barium (Ba), calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), lead (Pb), and zinc (Zn) were analyzed in 44 illicit heroin samples from Southeast Anatolia, Turkey. Illicit heroin samples were dissolved in nitric acid using microwave oven and were quantified by electrothermal atomic absorption spectrometry (Cd and Pb) and inductively coupled plasma-atomic emission spectrometry (Al, Ba, Ca, Cu, Fe, Mg, Mn, and Zn). The most abundant element was calcium, 4050 to 14200 mug/g, which could be ascribed to the use of lime in the manufacturing process and/or as diluting agent. Iron (180 to 1470 mug/g), aluminum (42 to 2280 mug/g), and zinc (160 to 210 mug/g) were found at moderately high levels, possibly because of the use of metal pots in the acetic anhydride cooking process and also for storage. Cadmium and lead concentrations were at the lowest measured levels. The amounts of magnesium, manganese, barium, and copper were in the range of 100 to 800 mug/g, 3 to 17 mug/g, 4 to 30 mug/g, and 2 to 46 mug/g, respectively.Öğe Matrix effects of concomitant species on the determination of nickel by inductively coupled plasma atomic emission spectrometry(Mrs Pushpa Agarwal, 2005) Akba, O; Baysal, A; Merdivan, M; Hamamci, C; Gumgum, BThe interference on the determination of nickel by the salts LiCl, NaCl, KCl, CsCl, NH4Cl, Na2SO4, NaNO3, NaC2H3O2 in an inductively coupled plasma-atomic emission spectrometry has been carried out. The salt concentration was in the 100-10000 mg L-1 range. Nickel emission was enhanced at lower matrix concentrations (100 mg L-1) and was depressed at higher matrix concentrations (10000 mg L-1). Except cesium, above 100 mg L-1, all studied ions caused a decrease in the signal intensity in the range of 0-15%. The sequence order of the investigated ions for the enhancement and depression was unstable. The sequence order in enhancement was found as Li+ < Na+ < K+ < Cs+ < NH4+ for cation; NO3- < SO42- < Cl- < OAc- for anions and Cs+ < NH4+ < K+ < Li+ < Na+ for cat-ions and OAc- < SO42- Cl- < NO3- for anions in depression at the studied lines.Öğe Polymer supported humic acid for separation and preconcentration of thorium(IV)(Taylor & Francis Inc, 2004) Erdogan, S; Merdivan, M; Hamamci, C; Akba, O; Baysal, AThe resin impregnating humic acid (HA) onto XAD-4 has been prepared to investigate adsorption behaviour of Th(IV). The characterization of the resulting resin has been carried out by infrared spectral data and sorption capacity. Maximum adsorption capacity of Th(IV) on the resin is found to be 1.51 X 10(-4) mol g(-1) at pH 4. The sorbent was found to possess a high selectivity for Th(IV) with an optimum extraction pH around 3-7. Recoveries for Th(IV) determined prior to breakthrough were found to be quantitative (96-99%). The resin exhibits good chemical stability, reuseability, and a faster rate of equilibration for Th(IV) determination. The influence of several ions as interferents is discussed. The method has been successfully applied for the separation of Th(IV) in synthetic mixtures.Öğe Pyrolysis kinetics and chemical composition of Hazro coal according to the particle size(Springer, 2005) Duz, MZ; Tonbul, Y; Baysal, A; Akba, O; Saydut, A; Hamamci, CThe relationship between particle size and chemical composition of Hazro coal (origin: SE Anatolia, Turkey) has been examined by elemental analysis and by thermogravimetric pyrolysis. The chemical composition of the coal was determined by grinding sample particles physically and separating according to their size in mm by sieving. Particle size distribution of the coal and chemical composition of these fractions were given. The coal has been non-isothermally pyrolysed in a thermogravimetric analyser to determine the kinetic factors. Thermal gravimetric (TG/DTG) experiments were performed from ambient temperature to 800 degrees C under a nitrogen atmosphere at heating rate 10 K min(-1) with five different particle size ranges. Kinetic parameters of the samples were determined using a Coats and Redfern kinetic model, assuming a first-order reaction. Depending on the particle size of the coal samples, the mean activation energy values varied between 49.1 and 84.6 kJ mol(-1). The results discussed indicate that activation energies increase as the particle size decreases.Öğe The solvent extraction of alkali metal picrates with 4,13-N,N?-dibenzyl-4,13-diaza-18-crown-6(Elsevier Science Bv, 1998) Hamamci, C; Hosgoren, H; Erdogan, SExtraction of alkali metal picrates with N,N'-dibenzyl-18-crown-6 was carried out, with dichloromethane as water-immiscible solvent, as a function [ligand]/[metal cation]. The extractability of metal picrates (Li+, Na+, K+ Rb+, Cs+) was evaluated as a function of [L]/[M+]. The extractability of complex cation-picrate ion pairs decreases in this sequence: Li+ > Rb+ > Cs+ > K+ > Na+. The overall extraction equilibrium constants (K-ex) for complexes of N,N'-dibenzyl-18-crown-6 with alkali metal picrates between dichloromethane and water have been determined at 25 degrees C. The values of the extraction constants (log K-ex) were determined to be 10.05, 6.83, 7.12, 7.83, 6.73 for Li+ Na+, K+, Rb+ and Cs+ compounds, respectively. DB186 shows almost 2-fold extractability against Li+ compared to the other metal picrates, whereas it shows no obvious extractability difference amongst the other metal cations when [L]/[M+] is 0.2-1. However, an increasing extractability is observed for Cs+ when [L]/[M+] [1]. (C) 1998 Elsevier Science B.V. All rights reserved.Öğe Sorption behaviour of uranium(VI) with N,N-dibutyl-N?-benzoylthiourea Impregnated in Amberlite XAD-16(Elsevier Science Bv, 2001) Merdivan, M; Düz, MZ; Hamamci, CThe sorption of U(VI) by N, N-dibutyl, N'-benzoylthiourea (DBBT) impregnated resin has been studied. DBBT impregnated resin was prepared by direct adsorption of chelating ligand onto macroporous support, Amberlite XAD-16. The adsorption of DBBT on the macroporous support is shown by FTIR spectroscopy to be the result of only weak chelating ligand-support interactions. Parameters such as the pH effect on the sorption of uranium, the sorption capacity of the impregnated resin, the stripping of uranium and the effect of coexisting ions were investigated by batch experiments. The results demonstrated that uranium(VI) ions, at pH 4.5-7 could be sorbed completely using 0.1 g Amberlite XAD-16 resin loaded with DBBT. The sorption capacity of the impregnated resin is 0.90 mmol uranium(VI) g(-1). Quantitative recovery of U(VI) is achieved by stripping with 0.1 M HNO3. The method was applied to the determination of uranium in synthetic samples. The precision of the method was 2.4 RSD% in a concentration of 1.20 mug ml(-1) for ten replicate analysis. (C) 2001 Elsevier Science B.V. All rights reserved.Öğe Thorium(IV) and uranium(VI) sorption studies on octacarboxymethyl-C-methylcalix[4]resorcinarene impregnated on a polymeric support(Elsevier, 2003) Demirel, N; Merdivan, M; Pirinccioglu, N; Hamamci, CThe impregnation of octacarboxymethyl-C-methylcalix[4]resorcinarene into a polymeric matrix, Amberlite XAD-4, is reported and was characterized by infrared spectroscopy. The sorption capacity of the impregnated resin is 0.34 x 10(-3) mol g(-1). The resin was used for the sorption of thorium(IV) and uranium(VI) from aqueous solution. The properties of capacity, pH effect, and breakthrough curves of the impregnated resin were investigated. The capacity of the resin for Th(IV) and U(VI) was found to be 0.29 and 0.27 x 10(-3) mol g(-1), respectively. The metal ions were eluted with 0.4-2 M HCl or HNO3. Chromatographic separation of Th(W) and U(VI) was accomplished by adjustment of pH to 3.0 and 6.0, respectively. The impregnated resin exhibits a high chemical stability, reusability and fast equilibration. Separation of Th(W) and U(VI) from other metal cations in synthetic solution was achieved. (C) 2003 Elsevier Science B.V. All rights reserved.
