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    Application of Modified BCR Sequential Extraction Method for the Fractionation and ICP-OES Determination of Copper in Asphaltite Combustion Waste
    (PERKIN-ELMER CORP, 2013) Aydin, Firat; Gunduz, Beniz; Aydin, Isil; Akba, Osman; Saydut, Abdurrahman; Hamamci, Candan
    Asphaltite is derived from petroleum-origin solid fossil fuel. It contains many elements in different forms which may change during the combustion process. This study presents a modified BCR sequential extraction method for the fractionation of copper (Cu) in asphaltite combustion waste (ACW) into four forms (exchangeable, reducible, oxidizable, and residual) and determination by inductively coupled plasma optical emission spectrometry (ICP-OES). The 327.393 nm line was used because it offers highest detectability and is free from major spectral interferences. A two-stage microwave acid digestion program was used for preparation of the samples. The total Cu concentration in the ACW was 104.56 mg kg(-1) dry weight (d.w). The most abundant copper fraction in the studied ACW samples was found as residual fraction of Cu (59.94 mg kg(-1) d.w.). The relative abundances of the remaining Cu fractions in ACW were as follows: exchangeable + water- and acid-soluble (19.07 mg kg(-1) d.w.) > oxidizable (17.49 mg kg(-1)' d.w.) > reducible (7.65 mg kg(-1) d.w.). The results were found to be in good agreement with the certified values. The advantages of the technique include a high degree of automation, good reproducibility, and short analysis time, which makes it the method of choice for the fractionation of Cu.
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    Chemical Speciation of Vanadium in Coal Bottom Ash
    (WILEY, 2012) Aydin, Firat; Saydut, Abdurrahman; Gunduz, Beniz; Aydin, Isil; Hamamci, Candan
    Chemical speciation of vanadium is important to understand the true nature of this element in the environment as well as its biochemical pathways. Sample pretreatment, preparation, and chemical speciation methods were applied for vanadium in coal bottom ash here. Two-stage microwave acid digestion was used to preparation of samples. Determination of vanadium was performed using inductively coupled plasma-optical emission spectrometry (ICP-OES). Speciation of vanadium was carried out using a seven-step sequential extraction procedure of the coal bottom ash each releasing species of vanadium: Water soluble, exchangeable, carbonate, reducible, oxidizable, sulfide, and residual fractions. Total vanadium concentration in the coal bottom ash is 701?mg?kg-1 d.w. The most abundant form of vanadium in coal bottom ash is residual fraction of vanadium (196?mg?kg-1 d.w.). Relative abundances of the remaining vanadium fractions in coal bottom ash are as follows: Reducible (176?mg?kg-1 d.w.)?>?sulfide (176?mg?kg-1 d.w.)?>?carbonate (85?mg?kg-1 d.w.)?>?oxidizable (50?mg?kg-1 d.w.)?>?water soluble (10.6?mg?kg-1 d.w.)?>?exchangeable (9.0?mg?kg-1 d.w.).
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    Comparative Determination of Phosphorus Fractions in Coastal Surface Sediment (NE Mediterranean Sea) by ICP-OES and UV/VIS Spectrometry
    (PERKIN-ELMER CORP, 2018) Aydin, Isil; Temel, Zihni; Gunduz, Beniz; Aydin, Firat
    The role of phosphorus (P) in sediments in promoting marine eutrophication can be more efficiently evaluated by considering different P fractions instead of total P content. This paper presents the P distribution (total P, organic P, and fractions of inorganic P; loosely adsorbed P, and P bound to aluminium, P bound to calcium, and P bound to iron, as well as total inorganic P) in surface sediments collected in June 2015 at the NE Mediterranean Sea (due to extensive tourism is under anthropogenic pressure) using chemical (sequential extraction) fractionation techniques. A number of fractions were collected for each reagent for subsequent colorimetric determination using UV/Vis spectrometry and ICP-OES determination. The two methods show similar results for the P and the concentrations are in good agreement with the reference values. The results presented P-bound calcium as the major P fraction in the surface sediments collected, mainly due to the oversaturation of calcite and the co-precipitation of phosphate. Relative abundances of the remaining P fractions follow the order: Fe-P > Al-P > loosely bound P for coastal surface sediment.
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    Content and Mobility Behavior of Iron and Manganese in Asphaltite Burning Residue Using ICP-OES
    (PERKIN-ELMER CORP, 2014) Aydin, Isil; Gunduz, Beniz; Aydin, Firat; Akba, Osman; Saydut, Abdurrahman; Hamamci, Candan
    The determination of inorganic pollutants leaching from solid waste, such as coal, asphaltite, oil shale, and ash, is an important topic for industrial applications and solid waste management. This study presents the concentration and fractionation of iron (Fe) and manganese (Mn) in asphaltite burning residue (ABR) and their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). A modified Tessier sequential extraction method was used for the fractionation of Fe and Mn in four forms (exchangeable, carbonates, bound to organic and sulfide, and residual content). Investigations on the Fe and Mn chemical fractions and their environmental mobility in ash solution systems were carried out. It was found that Mn in ABR (from Harbul-Silopi, Turkey) occurs in the following fractions: exchangeable (13.56%), associated with carbonates (28.94%), associated with organic matter and sulfides (17.48%), and residual content (40.08%). Fe occurs in the following fractions: exchangeable (11.11%), carbonates (27.68%), organic matter and sulfides (23.39%), and residual content (37.82%). Among these fractions, the exchangeable and carbonate-bound fractions are unstable and prone to leach out, while the organic matter-bound fractions and the residual fractions are considered to be relatively stable and of low bioavailability. Thw mobility fractions of Fe contain 38.79% and of Mn contain 42.50% of their total concentration in ABR under normal environmental conditions.
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    Polymerization capacity of orthodontic composites analyzed by Fourier transform infrared spectroscopy
    (MOSBY-ELSEVIER, 2011) Corekci, Bayram; Malkoc, Siddik; Ozturk, Bora; Gunduz, Beniz; Toy, Ebubekir
    Introduction: The aim of this in-vitro study was to analyze the polymerization capacity of 5 orthodontic composites by determining the degree of monomer conversion (DC). Methods: Fourier transform infrared spectroscopy was used to evaluate the DC of the orthodontic composites immediately after polymerization and after storage in artificial saliva at 37 degrees C +/- 1 degrees C for 30 days. The resin-based adhesive composites investigated were Bisco Ortho (Bisco, Schaumburg, III), Heliosit Orthodontics (Ivoclar, Schaan, Liechtenstein), Kurasper F (Kuraray, Okayama, Japan), Light Bond (Reliance Orthodontic Products, Itasca, III), and Transbond XT (3M Unitek, Monrovia, Calif), cured with Elipar FreeLight 2 (3M ESPE, St Paul, Minn) for the testing of the DC values. Fifty cylindrical specimens were manufactured in molds. The data were analyzed by 2-factor analysis of variance (ANOVA) and Tukey HSD test. Results: According to 2-way ANOVA, the DC was significantly influenced by composite type (P < 0.05); after 30 days, there were no differences among the composite types for the DC. The interaction of orthodontic composites and time played a statistically significant role in the DC (P < 0.05), but there was no statistically significant influence of time for the DC (P > 0.05). Conclusions: The DC was found to change according to composite materials used, and Bisco Ortho showed the most DC performance. The DC of orthodontic composites is a complex process that is affected not only by inorganic filler content of the composite but also the monomer type and many other factors. Sufficient DC values of 5 commercially available orthodontic composites can be achieved with a new-generation light-emitting diode curing light. (Am J Orthod Dentofacial Orthop 2011;139:e299-e304)
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    Study of phosphorus distribution in coastal surface sediment by sequential extraction procedure (NE Mediterranean Sea, Antalya-Turkey)
    (ELSEVIER SCIENCE BV, 2011) Gunduz, Beniz; Aydin, Firat; Aydin, Isil; Hamamci, Candan
    The paper presents the results of the distribution of phosphorus (P) bioavailability (total P. organic and inorganic P) in marine surface sediments collected from four coasts that are under different anthropogenic pressures of NE Mediterranean Sea (Alanya, Serik, Kemer, Finike - Antalya, Turkey) in May, 2009. Speciation of inorganic phosphorus (IP) was carried out using a method on sequential extractions, with each releasing four forms of IP loosely bound P, phosphorus bound to aluminum (P-Al). phosphorus bound to iron (P-Fe), and phosphorus bound to calcium (P-Ca) and determined by the inductively coupled plasma-optical emission spectrometer (ICP-OES). The total P contents ranged from 152.18 to 275.12 mg/kg. It was found that more than 96% of the total P is IP. Among the four forms of IP, IP distribution ranges were 1.20-3.59% for loosely bound P, 2.38-4.74% for P-Fe, 4.43-8.55% for P-AI, and 84.36-91.99% for P-Ca. The region of Alanya was characterized by the highest total P concentration in the surface sediment than Serik, Kemer, Finike sediments. For all the marine surface sediment samples, the rank order of inorganic P-fractions was Ca-P > Al-P > Fe-P > loosely bound P. (C) 2010 Elsevier B.V. All rights reserved.
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    Surface modification of glass beads with an aminosilane monolayer
    (SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2006) Arslan, Gulsin; Ozmen, Mustafa; Gunduz, Beniz; Zhang, Xunli; Ersroz, Mustafa
    Surface modification of glass beads with a self-assembled monolayer of (3-Aminopropyl)-triethoxysilane (APTES) was investigated. Characterisation of the self-assembled monolayer was confirmed by a reaction between amine terminal groups and thionylchloride of Rhodamine-B dye using fluorescence microscopy. Quantitative 3-dimensional profiling was obtained for all modification processes by converting microscopic images to numerical values. The reaction steps were also analysed using infrared spectroscopy (FTIR).
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    Use of Sequential Extraction With UV/Vis Spectrophotometer to Assess Phosphorus Species in Surface Sediments (NE Mediterranean Sea)
    (PERKIN-ELMER CORP, 2010) Gunduz, Beniz; Aydin, Isil; Bakirdere, Sezgin; Saydut, Abdurrahrnan; Aydin, Firat
    The speciation of total phosphorus in different forms is necessary to understand the phosphate exchange mechanisms in sediments, its potential removal from the water column, and the availability of phosphorus for primary producers. This paper presents the phosphorus (P) distribution (total phosphorus, organic phosphorus, and forms of inorganic phosphorus; loosely adsorbed phosphorus and phosphorus bound to aluminium, phosphorus bound to calcium, and phosphorus bound to iron, as well as total inorganic phosphorus) in surface sediments collected from two coasts (each under different anthropogenic pressures) in the eastern Mediterranean Sea in April 2007. The sampling stations are located at on the south-eastern Mediterranean coast of Turkey, adjacent to the Cilician Basin. The most abundant phosphorus in studied surface sediments was found as calcium-bound phosphorus. Relative abundances of the remaining phosphorus forms follow the order: P-Al > loosely bound-P> P-Fe. The concentration of total phosphorus in the surface sediments taken from Tasucu was found to be higher than the sediments from Erdemli. Accuracy of the method was checked by using NCS DC 73316 certified reference material and the results found were found to be in good agreement with the certified value. Maximum values of total P in Erdemli and Tasucu were 220.35 and 321.42 mu g g(-1), respectively.