Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Serencam, Huseyin(6)
- Cinar, Mehmet(5)
- Duran, Celal(5)
- Gurbuz, Fatih(5)
- Karabacak, Mehmet(5)
- Chova, LG(4)
- Martinez, AL(4)
- Ozdes, Duygu(4)
- Torres, IC(4)
- Aksoy, Gokhan(3)
- Toklu, Y.C.(3)
- Bekdaş, Gebrail(2)
- Bongaerts, Roy J.(2)
- Cansiz, Ahmet(2)
- Chinna Babu, P.(2)
- Cinar, M.(2)
- Degirmenci, Yavuz(2)
- Dertli, Enes(2)
- Erdem, Suat(2)
- Isleyen, Tevfik(2)
- Karabacak, M.(2)
- Karadag, Zekeriya(2)
- Karagoz, Sendogan(2)
- Kurt, M.(2)
- Küçük Demir, Betül(2)
- Mayer, Melinda J.(2)
- Nadaroglu, Hayrunnisa(2)
- Narbad, Arjan(2)
- Omeroglu, Gokhan(2)
- Prasad, Onkar(2)
- Salar, Riza(2)
- Sinha, Leena(2)
- Sundaraganesan, N.(2)
- Toklu, Yusuf Cengiz(2)
- Tufekci, Mehmet(2)
- Turgut, Umit(2)
- Uzun, F.(2)
- Çakir, Uǧur(2)
- Çomakli, Kemal(2)
- İlter, İlhan(2)
Yayınlar
- MakaleYalnız künye2013Scopus SJRQ3Application of carrier element free coprecipitation (CEFC) method for determination of Co(II), Cu(II) and Ni(II) ions in food and water samples
Serencam, Huseyin; Duran, Celal; Ozdes, Duygu; Bektas, Hakan
A simple and highly sensitive separation and preconcentration procedure, which has minimal impact on the environment, has been developed. The procedure is based on the carrier element free coprecipitation (CEFC) of Co(II), Cu(II), and Ni(II) ions by using 2-{4-[2-(1H-indol-3-yl)ethyl]-3-(4-methylbenzyl)-5-oxo- 4,5-dihydro-1H-1,2,4-triazol- 1-yl}-N'-(pyridin-2-yl methylidene)acetohydrazide (IMOTPA), as an organic coprecipitant. The levels of analyte ions were determined by flame atomic absorption spectrometry (FAAS). The detection limits for Co(II), Cu(II) and Ni(II) ions were found to be 0.40, 0.16 and 0.17 μg L-1, respectively, and the relative standard deviations for the analyte ions were lower than 3.0%. Spike tests and certified reference material analyses were performed to validate the method. The method was successfully applied for the determination of Co(II), Cu(II) and Ni(II) ions levels in sea and stream water as liquid samples and red pepper, black pepper, and peppermint as solid samples.
AtıfScopus10WoS10
İncele - MakaleAçık Erişim2013Scopus SJRQ2Time-dependent effect of salicylic acid on alleviating cold damage in two barley cultivars differing in cold tolerance
Mutlu, Salih; Karadaǧoǧlu, Ömer; Atici, Ökkeş; Taşǧin, Esen; Nalbantoǧlu, Barbaros
The time-dependent effect of salicylic acid (SA) on alleviating cold damage in the Tokak (tolerant) and Akhisar (sensitive) varieties of barley (Hordeum vulgare) was investigated. Seedlings subjected to 0.0, 0.1, and 1 mM SA for 7 days were transferred to cold (7/5 °C) on days 7, 14, 21, and 28 for 3 days. It was found that 0.1 mM SA had a greater alleviating effect, decreasing the freezing injury in both varieties for at least 10 days after the application. Moreover, 0.1 mM SA had a greater effect on alleviation in Tokak by increasing the ice nucleation activity of apoplastic proteins extracted from the leaves. SA was effective for at least 24 days in decreasing the effect of freezing temperature by regulating apoplastic proteins in the leaves after the application. Furthermore, 0.1 and 1 mM SA had an alleviating effect by decreasing the lipid peroxidation level in both varieties for at least 24 days after the application. It can be seen that SA treatment can play a positive role in alleviating cold damage in barley. Therefore, it is suggested that results from SA treatments may contribute to research related to diminishing cold damage in agricultural applications.
AtıfScopus21WoS8OpenAlex23İncele - MakaleAçık Erişim2013Scopus SJRQ2Biosorption properties of Morus alba L. for Cd (II) ions removal from aqueous solutions
Serencam, Huseyin; Ozdes, Duygu; Duran, Celal; Tufekci, Mehmet
The abundantly available industrial waste product Morus alba L. pomace (MAP) is one of the cost-effective biosorbent for removal of metal ions from aqueous solutions. Hence, in the present study, we aimed to test the ability of MAP to remove Cd(II) ions through batch biosorption process. Firstly, MAP was characterized using several techniques, and then the influence of various experimental parameters such as initial pH of the aqueous solution, initial Cd(II) concentration, contact time, MAP concentration, and temperature were evaluated upon the biosorption process. It was found that the maximum uptake of Cd(II) ions occurred at initial pH 6.0 and optimum contact time was observed as 60 min. Cd(II) ions adsorption on MAP analyzed by the Langmuir and Freundlich isotherm models and the maximum monolayer biosorption capacity of MAP was found to be 21.69 mg g-1 by using the Langmuir isotherm model. The pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models were employed to describe the biosorption kinetics. In order to investigate the thermodynamic properties of the biosorption process, the changes in the Gibbs free energy (â̂†G), enthalpy (â̂†H), and entropy (â̂†S) were also evaluated and it has been concluded that the process was feasible, spontaneous, and endothermic in the temperature range of 5-40 C.
AtıfScopus38WoS36OpenAlex46İncele - MakaleAçık Erişim2013Scopus SJRQ4Protective Role of Mentha longifolia L. ssp. longifolia against Aflatoxin B
Ceker, Selcuk; Agar, Guleray; Alpsoy, Lokman; Nardemir, Gokce; Kizil, Hamit Emre; Mete, Ebru
The aim of this study was to investigate the effects of essential oil of Mentha longifolia L. ssp. longifolia, used since ancient times for the treatment of many digestive tract diseases, on the genotoxicity and oxidative stress by a single dose of Aflatoxin B1 (5 μM) in the human lymphocyte culture. The total of the 12 identified components accounted for 97.69 % by Gas chromatography (GC). Major components of the oil were cis-piperitone epoxide (26.52 %), piperitenone oxide (26.40 %), pulegone (15.66 %) and piperitenone (13.57 %). According to the results obtained from GC-MS systems, monoterpenes consist of 89.19 % of the total oil approximately while sesquiterpenes were represented in small quantities in the oil. We studied the anti-genotoxic effects of essential oils of M. longifolia (MEO) by using sister chromatid exchange (SCE) and micronucleus (MN) test systems. Also, the anti-oxidative effects of MEO were evaluated by using superoxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA) assay. The SCE frequency and the number of MN were increased when treated with AFB1. Especially, MEO at 1.5 and 2.0 μl reduced SCE frequency and MN number in the human lymphocyte (p <0.05). In addition, AFB1 treatment significantly reduced the activity of SOD and GPx and elevated the level of MDA (p<0.05). MEOs treatment led to significant attenuation of AFB1-induced oxidative stress by normalization of the activities of SOD and GPx and the MDA (p < 0.05). These results suggest that MEOs could provide anti-oxidative and anti-genotoxic protection for the oxidative and genotoxic agents that cause many diseases including cancer and neurodegenerative disease.
AtıfScopus10WoS11OpenAlex11İncele - MakaleAçık Erişim2013Scopus SJRQ1Spontaneous Mutation Reveals Influence of Exopolysaccharide on Lactobacillus johnsonii Surface Characteristics
Horn, Nikki; Wegmann, Udo; Dertli, Enes; Mulholland, Francis; Collins, Samuel R. A.; Waldron, Keith W.; Bongaerts, Roy J.; Mayer, Melinda J.; Narbad, Arjan
As a competitive exclusion agent, Lactobacillus johnsonii FI9785 has been shown to prevent the colonization of selected pathogenic bacteria from the chicken gastrointestinal tract. During growth of the bacterium a rare but consistent emergence of an altered phenotype was noted, generating smooth colonies in contrast to the wild type rough form. A smooth colony variant was isolated and two-dimensional gel analysis of both strains revealed a protein spot with different migration properties in the two phenotypes. The spot in both gels was identified as a putative tyrosine kinase (EpsC), associated with a predicted exopolysaccharide gene cluster. Sequencing of the epsC gene from the smooth mutant revealed a single substitution (G to A) in the coding strand, resulting in the amino acid change D88N in the corresponding gene product. A native plasmid of L. johnsonii was engineered to produce a novel vector for constitutive expression and this was used to demonstrate that expression of the wild type epsC gene in the smooth mutant produced a reversion to the rough colony phenotype. Both the mutant and epsC complemented strains had increased levels of exopolysaccharides compared to the wild type strain, indicating that the rough phenotype is not solely associated with the quantity of exopolysaccharide. Another gene in the cluster, epsE, that encoded a putative undecaprenyl-phosphate galactosephosphotransferase, was deleted in order to investigate its role in exopolysaccharide biosynthesis. The ΔepsE strain exhibited a large increase in cell aggregation and a reduction in exopolysaccharide content, while plasmid complementation of epsE restored the wild type phenotype. Flow cytometry showed that the wild type and derivative strains exhibited clear differences in their adhesive ability to HT29 monolayers in tissue culture, demonstrating an impact of EPS on surface properties and bacteria-host interactions.
AtıfScopus71WoS66OpenAlex72İncele - MakaleYalnız künye2013Scopus SJRQ3Bacteria-modified red mud for adsorption of cadmium ions from aqueous solutions
Kalkan, Ekrem; Nadaroglu, Hayrunnisa; Dikbaş, Neslihan; Taşgin, Esen; Çelebi, Neslihan
Cadmium is a toxic metal widely used in industry and it enters the environment from electroplating, smelting, alloy manufacturing, pigments, plastics, cadmium-nickel batteries, fertilizers, pesticides, mining, pigments and dyes, textile operations, and refining industries. Considering the harmful effects of cadmium, it is necessary to remove cadmium from liquid wastes at least to the limit accepted by regulations. The present study describes removal of cadmium from aqueous solutions using bacteria-modified red mud waste material. Batch adsorption experiments have been performed as a function of pH, contact time, temperature, and adsorbent dosage. The optimum results were obtained at pH 4.0, contact time of 60 min, temperature of 30°C, and an adsorbent dose of 1 mg/mL. The adsorption data was correlated with Langmuir and Freundlich adsorption models. The maximum adsorption capacity obtained from Langmuir adsorption model was 83.034 mg/g. The kinetic processes of cadmium adsorption on bacteria-modified red mud were described by applying pseudo-first-order and pseudo-second-order rate equations. The kinetic data for the adsorption process obeyed pseudo-second-order rate equations. Various thermodynamic parameters, such as ΔG°, ΔH°, and Δ15° were calculated and the negative value of ΔG° obtained indicate that the process was spontaneous, and the positive value of ΔH° confirms the reaction to be endothermic, and the positive value of ΔS° shows that the decrease in the degree of freedom of the adsorbed species. The bacteria-modified red mud investigated in this study exhibited a high potential for the removal of cadmium from aqueous solutions.
AtıfScopus30İncele - MakaleYalnız künye2013Scopus SJRQ2Molecular structure, electronic properties, NLO, NBO analysis and spectroscopic characterization of Gabapentin with experimental (FT-IR and FT-Raman) techniques and quantum chemical calculations
Sinha, Leena; Karabacak, Mehmet; Narayan, V.; Cinar, Mehmet; Prasad, Onkar
Gabapentin (GP), structurally related to the neurotransmitter GABA (gamma-aminobutyric acid), mimics the activity of GABA and is also widely used in neurology for the treatment of peripheral neuropathic pain. It exists in zwitterionic form in solid state. The present communication deals with the quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers of GP using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. In view of the fact that amino acids exist as zwitterions as well as in the neutral form depending on the environment (solvent, pH, etc.), molecular properties of both the zwitterionic and neutral form of GP have been analyzed. The fundamental vibrational wavenumbers as well as their intensities were calculated and compared with experimental FT-IR and FT-Raman spectra. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The electric dipole moment, polarizability and the first hyperpolarizability values of the GP have been calculated at the same level of theory and basis set. The nonlinear optical (NLO) behavior of zwitterionic and neutral form has been compared. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using natural bond orbital analysis. Ultraviolet-visible (UV-Vis) spectrum of the title molecule has also been calculated using TD-DFT method. The thermodynamic properties of both the zwitterionic and neutral form of GP at different temperatures have been calculated.
AtıfScopus53WoS53OpenAlex58İncele - MakaleAçık Erişim2013Scopus SJRQ2Energetic and exergetic comparison of air to air and air to water heat pumps according to evaporator conditions
Çomakli, Kemal; Çakir, Uǧur; Şahin, Erol; Kuş, Ayşegül Çokgez
This paper presents an experimental energetic and exergetic comparison for a heat pump system that can be run in different modes as air to air and air to water. Components of the heat pump do not change when the running mode changes, except for the condenser. This means that some external and internal effects (like compressor type, pipe lines) that can affect the system performance will be the same for each running mode. The comparison which was made in this study demonstrates which system leads to an efficient conversion and supply of energy and exergy. In the analysis, four balance (mass, energy, entropy and exergy) equations are applied to the system for the two modes. Exergy and energy efficiency values for both systems are given, while exergy destructions in each of the systems are determined and presented. It is seen that the heat pump unit which has the highest COP value is the air to air type (3.45-3.8); second is the air to water type (3.35-3.41). The exergy efficiency of the air to air heat pump (29-32%) is higher than the exergy efficiency of the air to water type heat pump (24.1-25). Ranking of the exergy destruction rates of the two heat pump types from high to low is as follows: air to air and air to water.
AtıfScopus5OpenAlex5İncele - MakaleAçık Erişim2013Scopus SJRQ2Application of S-UTD-CH model into multiple diffraction scenarios
Tabakcioglu, Mehmet Baris; Cansiz, Ahmet
Propagation prediction models based on ray tracing in coverage estimation for digital broadcasting systems are compared. Geometrical Theory of Diffraction (GTD), Slope Uniform Theory of Diffraction (S-UTD), and Slope UTD with Convex Hull (S-UTD-CH) models are compared for computation time and propagation path loss. S-UTD-CH model is optimum model with respect to computation time and relative path loss.
AtıfScopus8WoS7OpenAlex11İncele - MakaleYalnız künye2013Scopus SJRQ2Experimental and theoretical FTiR and FT-Raman spectroscopic analysis of 1-pyrenecarboxylic acid
Karabacak, M.; Cinar, M.; Kurt, M.; Chinna Babu, P.; Sundaraganesan, N.
The title molecule 1-pyrenecarboxylic acid (1PCA) has been characterized by FTiR, FT-Raman, NMR and UV-Vis spectral analyses. The molecular geometry, harmonic vibrational modes, the corresponding wavenumbers and iR intensities of 1PCA were calculated by DFT method with 6-311G(d, p) basis set. The assignments of the fundamentals were proposed on the basis of total energy distribution (TED) calculations. The calculated 13C and 1H NMR chemical shifts using gauge including atomic orbitals (GiAOs) approach are in good agreement with the observed chemical shifts. The polarizability and first order hyperpolarizability of the title molecule were calculated and interpreted. Using TD-DFT method, the electronic transitions have been compared with the experimental wavelengths. The molecular electrostatic potential map was used for prediction of possible hydrogen and oxygen bonding sites 1PCA molecule.
AtıfScopus45WoS43OpenAlex46İncele - MakaleYalnız künye2013Scopus SJRQ1Determination of aroma profiles of olive oils from Turkish olive cultivars
Bayrak, Ali; Kıralan, Mustafa; Kara, Hasan Hüseyin
This study analyzed volatile aromatic compounds present in the oils of Turkish olive cultivars. The cultivars Gemlik, AyvalIk, Memecik, Domat, Uslu, HalhalI, Kilis yaǧlIk, Nizip yaǧlIk, Haşebi and Karamani were harvested from important Turkish olive-growing locations, such as BalIkesir, Bursa, Manisa, AydIn, Muǧla, İzmir, Kilis, Mersin, Hatay and Gaziantep during the 2007-2008 and 2008-2009 growing seasons. Olive samples were collected in two harvest years, at almost the same maturity stage, and processed under the same conditions. Headspace solid-phase microextraction (HS-SPME) was used to analyze volatile aroma compounds in the olive oil samples. Forty-seven compounds were characterized and quantified using gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID). The most abundant identified compounds were trans-2-hexenal, hexanal and 3-methyl-1-butanol. The trans-2-hexenal, hexanal and 3-methyl-1-butanol contents of oil samples varied between 0.86-67.15, 3.93-61.82 and 0.48-84.74 %, respectively.
AtıfScopus11WoS11OpenAlex11İncele - BildiriYalnız künye2013Nonlinear analysis of structures by Total Potential Optimization using Metaheuristic Algorithms (TPO/MA)
Toklu, Y.C.; Bekdaş, G.; Temür, R.; Toklu, Ş.Ç.; Uzun, F.; de Wilde, P.; Suter, G.; Rafiq, Y.
Structural analysis problems can be formulized as either root finding problems, or optimization problems. The general practice is to choose the first option directly or to convert the second option again to a root finding problem by taking relevant derivatives and equating them to zero. The second alternative is used very randomly as it is and that only for some simple demonstrative problems, most probably due to difficulty in solving optimization problems by classical methods. The method called Total Potential Optimization using Metaheuristic Algorithms (TPO/MA) described in this study successfully enables handling structural problems with optimization formulation. Using metaheuristic algorithms provides additional advantages in dealing with all kinds of constraints.
AtıfScopus1İncele - BildiriYalnız künye2013Space applications of tensegric structures
Toklu, Y.C.; Temur, R.; Bekdas, G.; Uzun, F.
Tensile integrity (tensegrity, tensegric) structures are suggested for possible use in outer space and on space bodies because of their minimal need for structural materials, ease of transfer and mounting. Structurally their behavior is non-linear. It has been shown here that their structural analysis can successfully be performed by total potential optimization using meta-heuristic algorithms (TPO/MA). The named method is an emerging technique that combines minimum energy principle of mechanics with metaheuristic algorithms. The technique thus defined has been shown to be very efficient, accurate and robust in analyzing structures. The success of the technique is especially profound for non-linear structures. In this study the named technique is applied to tensile integrity (tensegrity, tensegric) structures which are known to be highly nonlinear, thus difficult to analyze.
AtıfScopus10İncele - MakaleAçık Erişim2013Scopus SJRQ1Solutions of an anisotropic nonlocal problem involving variable exponent
Avci, Mustafa; Ayazoglu, Rabil A.; Cekic, Bilal
The present paper deals with an anisotropic Kirchhoff problem under homogeneous Dirichlet boundary conditions, set in a bounded smooth domain Ω of ℝN (N ≥ 3). The problem studied is a stationary version of the original Kirchhoff equation, involving the anisotropic p→(.)-Laplacian operator, in the framework of the variable exponent Lebesgue and Sobolev spaces. The question of the existence of weak solutions is treated. Applying the Mountain Pass Theorem of Ambrosetti and Rabinowitz, the existence of a nontrivial weak solution is obtained in the anisotropic variable exponent Sobolev space W01p→(.) (Ω), provided that the positive parameter λ that multiplies the nonlinearity f is small enough.
AtıfScopus13WoS14OpenAlex9İncele - MakaleYalnız künye2013Scopus SJRQ1An experimental exergetic comparison of four different heat pump systems working at same conditions: As air to air, air to water, water to water and water to air
Çakir, Uǧur; Çomakli, Kemal; Çomakli, Ömer; Karsli, Süleyman
In this study, we designed a multifunctional heat pump system using just one scroll compressor and which can be run in four different modes, namely air to air, air to water, water to water and water to air, in order to make an experimental energetic and exergetic performance comparison. Experimental system consists of two condensers and two evaporators and uses R22 as working fluid. One of the evaporators and condensers uses water and the others use air as heat source/sink. Heating capacities of four heat pump types are equal to each other. It is realized by adjusting the mass flow rate and temperature level of external fluid of condenser. Results show that the heat pump unit which has the maximum COP (coefficient of performance) value is water to air type with 3.94 and followed by water to water type with 3.73, air to air type with 3.54 and air to water type with 3.40. Ranking of four heat pump types with respect to their mean exergy efficiency is as follows; water to air type with 30.23%, air to air type with 30.22%, air to water type with 24.77% and water to water type with 24.01%. Exergy destruction rates of the systems were investigated in this study and the results revealed that the heat pump type which has the maximum exergy destruction is air to air type with 2.93kW. The second highest one is air to water type with 2.84kW. The third highest one is water to air type with 2.64kW and last one is water to water type with 2.55kW. It is understood that the temperature of the evaporator external fluid affects the exergetic efficiency of the system more than the mass flow rate. In contrast to the previous, the dominant parameter which has more important effect on the exergy destruction of the heat pump unit is the mass flow rate of evaporator external fluid.
AtıfScopus55WoS46İncele - MakaleYalnız künye2013Scopus SJRQ2Analysis of trusses by total potential optimization method coupled with harmony search
Toklu, Yusuf Cengiz; Bekdaş, Gebrail; Temur, Rasim
Current methods of analysis of trusses depend on matrix formulations based on equilibrium equations which are in fact derived from energy principles, and compatibility conditions. Recently it has been shown that the minimum energy principle, by itself, in its pure and unmodified form, can well be exploited to analyze structures when coupled with an optimization algorithm, specifically with a meta-heuristic algorithm. The resulting technique that can be called Total Potential Optimization using Meta-heuristic Algorithms (TPO/MA) has already been applied to analyses of linear and nonlinear plane trusses successfully as coupled with simulated annealing and local search algorithms. In this study the technique is applied to both 2-dimensional and 3-dimensional trusses emphasizing robustness, reliability and accuracy. The trials have shown that the technique is robust in two senses: all runs result in answers, and all answers are acceptable as to the reliability and accuracy within the prescribed limits. It has also been shown that Harmony Search presents itself as an appropriate algorithm for the purpose.
AtıfScopus33WoS26OpenAlex26İncele - MakaleAçık Erişim2013Scopus SJRQ3Existence of solutions for an elliptic equation with nonstandard growth
Avci, M.; Mashiyev, R. Ayazoglu; Cekic, B.
This paper deals with the existence of solutions for some elliptic equations with nonstandard growth under zero Dirichlet boundary condition. Using a direct variational method and the theory of the variable exponent Sobolev spaces, we set some conditions that ensures the existence of nontrivial weak solutions.
AtıfScopus2OpenAlex2İncele - MakaleYalnız künye2013Scopus SJRQ2Separation and pre-concentration of palladium(II) from environmental and industrial samples by formation of a derivative of 1,2,4-triazole complex on Amberlite XAD-2010 resin
Serencam, Huseyin; Bulut, Volkan Numan; Tufekci, Mehmet; Gundogdu, Ali; Duran, Celal; Hamza, Sibel; Soylak, Mustafa
A simple separation/pre-concentration method was developed for extraction of Pd(II) in various environmental samples, based on its adsorption of 4-phenyl-5-{[(4-phenyl-5-pyridin-4-yl-4H-1,2,4-triazole-3-yl)thio]methyl}-4H-1,2,4-triazole-3-thyol (PPTTMET) complex on Amberlite XAD-2010 resin in a mini column. The ligand has high affinity for Pd(II) among many other metals that are taken into consideration. The flame atomic absorption spectrometry is employed to determine the concentration of Pd(II). The optimum working conditions which were determined are as follows: 0.05 mol L-1 HNO3 as working medium, 1.0 mol L-1 HCI in acetone as elution solvent, 0.75 mg of PPTTMET amount and 750 mL of sample volume. The system was independent from the flow rates between 3.1 and 23.1 mL min-1. The Pd(II) adsorption capacity of Amberlite XAD-2010 resin was found to be 12.8 mg g-1 and the enrichment factor was calculated as 375. The method was successfully applied for the determination of Pd(II) in motorway dust samples, anodic sludge, gold ore, industrial electronic waste materials and various water samples.
AtıfScopus17WoS15OpenAlex17İncele - MakaleYalnız künye2013Scopus SJRQ3Selective Separation, Preconcentration, and Determination of Au (III) Ions in Environmental Samples by Coprecipitation With a 1,2,4-Triazole Derivative
Ozdes, Duygu; Duran, Celal; Serencam, Huseyin; Şahin, Deniz
An effective, simple, lowcost, and accurate separation and preconcentration procedure which has minimal impact on the environment has been developed. It is based on the carrier element-free coprecipitation (CEFC) of Au(III)ions using N-benzyl-2-{[3-methyl-4-(2morpholine-4-ylethyl)-5-oxo-4,5-dihydro-1H-1,2, 4-triazole-1-yl] acetyl)hydrazinecarboxamide (BODAH) as an organic coprecipitant. Determination of the Au(IH) ion levels was performed by flame atomic absorption spectrometry (FAAS). The developed method provided a detection limit of 0.36 μg L-1 and the relative standard deviation for Au(III)ions was found to be 5.1%. Spike tests and certified reference material analyses were performed to validate the method. The developed method was systematically investigated in different sets of experimental parameters that influence the quantitative recovery of the Au(III)ions. Based on these investigations, the optimum conditions for the determination of Au(III) ions at trace levels were established. The coprecipitation method was applied to anodic slime, gold ore, soil, and water samples to determine their Au(III)levels.
AtıfScopus6İncele - MakaleAçık Erişim2013Scopus SJRQ1Damages on reinforced concrete buildings due to consecutive earthquakes in Van
Ates, Sevket; Kahya, Volkan; Yurdakul, Muhammet; Adanur, Suleyman
Consecutive earthquakes occurred on October 23rd, 2011 in Ercis and on November 9th, 2011 in Edremit that are townships located 90. km and 18. km far from Van city in Turkey, respectively. A total of 28,000 buildings were damaged or collapsed in the city center and the surrounding villages after the Ercis earthquake. This number reached 35,000 after the Edremit earthquake. In the area where the earthquakes occurred, almost all the reinforced concrete buildings were affected.This study presents field observations of damages on reinforced concrete buildings due to the consecutive earthquakes that occurred in Van, Turkey. Damages appearing in the buildings may occur due to several reasons such as site effect, poor construction quality, poor concrete strength, poor detailing in beam-column joints, detailing of stronger beam than column, soft stories, weak stories, inadequate reinforcement, short lap splices, incorrect end hook angle, and short columns. Aftershocks also caused progressive damages on the buildings within 17 days after the earthquakes. According to the results of this study, most of the damaged buildings were not designed and constructed according to the Turkish earthquake code, the so-called Specification for Buildings to be built in Seismic Zones.
AtıfScopus84WoS74OpenAlex92İncele