Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(74)
- Akkurt, Nevzat(39)
- Celik, Erkan(35)
- Serdar, Osman(35)
- Güler, Ömer(33)
- Kutlu, Banu(32)
- Paksoy, Mehmet Yavuz(32)
- Yucesan, Melih(31)
- Tekin, H.O.(30)
- Yildirim, Numan(30)
- Yildirim, Nuran Cikcikoglu(30)
- ALMisned, Ghada(28)
- Mete, Suleyman(26)
- Danabas, Durali(20)
- Ince, Muharrem(20)
- Serin, Faruk(20)
- Ates, Mehmet(19)
- Can, Erkan(19)
- Onat, Onur(18)
- Benzer, Fulya(17)
- Kocabaş, Mehmet(17)
- Tanyol, Mehtap(17)
- Kizak, Volkan(16)
- Alataş, Mevlüt(15)
- Aydin, Rahmi(15)
- Kahraman, Gökhan(15)
- Kilic, G.(15)
- Polat, Alper(15)
- Susam, Selim Orhun(15)
- Xu, Qian(15)
- Aslan, Naim(14)
- Guler, Omer(14)
- Gürler, Nedim(14)
- Karatay, Gülnaz(14)
- Utku, Anıl(14)
- Yildirim, N. C.(14)
- Özkul, İskender(14)
- Demirol, Ferhat(13)
- Erguven, Gokhan Onder(13)
- Firat, Erhan(13)
Yayınlar
- MakaleYalnız künye2018Scopus SJRQ1A quantitative risk analysis by using interval type-2 fuzzy FMEA approach: the case of oil spill
Akyuz, Emre; Celik, Erkan
Risk assessment in maritime domain is one of the most cited topics since maritime transportation poses potential hazard for human life, marine environment and property. To mitigate risk and enhance safety awareness in maritime transportation, safety researchers have been seeking proactive solutions. This article prompts a quantitative risk-based approach combining interval type-2 fuzzy sets (IT2FSs) with failure mode and effect analysis (FMEA) to perform a comprehensive risk analysis. Thus, potential failure modes and their effects are revealed by calculating risk prioritisation numbers (RPNs). Whilst the FMEA method provides a robust risk analysing tool with relevant control options, the IT2FSs deals with ambiguity and vagueness of linguistic assessment of decision-makers through the FMEA. Hence, expert’s linguistic assessment in risk assessment can be transformed into useful information in terms of enhancing safety and pollution prevention in maritime industry. To demonstrate the proposed approach, potential failures and effects of a real shipboard oil spill case are handled. The findings show that incomplete information exchanged with local maritime authorities, malfunction of oil skimmer and poor organization of shoreline clean-up team are the most important failures during case of oil spill. The proposed approach provides not only theoretical insight into the maritime transportation industry but also practical contributions to chemical/oil tanker safety and environmental protection by mitigating risk in terms of technical or operational aspects.
AtıfScopus95WoS80OpenAlex92
İncele - MakaleYalnız künye2018Scopus SJRQ2The determination of present and possible environmental risks in solid waste dumping site, Tunceli, Turkey
Yildirim, Nuran Cikcikoglu; Demirbilek, Deniz; Erguven, Gokhan Onder; Kayar, Rahime; Basaran, Senay; Tulpar, Dilan
Leachate was a major cause of high risk classification. This landfill was set as one with highest possible risk classification due to high vulnerability of private water wells to contamination from leachate flows. The aim of this study is to determine the present and possible environmental risks of the leachate spreading from solid waste dumping site in Tunceli and offer solutions for those determined environmental risks. For this purpose, the characteristics of the leachate were monitored at two station points detected in the solid waste dumping site for 7 months. The characteristics of the leachate were found for pH between 7.9 and 8.7. Oxidation reduction potential (ORP) occurred between − 143 and − 48 mV while conductivity was between 2.8 and 2.6 mS. Total solid matter (TSM) and suspended solid matter (SSM) were between 1000 and 7000 mg/l, 0.2–22.5 mg/l, respectively, while total volatile solids (TVS) occurred between 300 and 1800 mg/l for the two stations. Alkalinity was approximately between 290 and 5210 mg/l, while biological oxygen demand (BOD5) and chemical oxygen demand (COD) results were 15–606 mg/l and 60–1160 mg/l, respectively, for two stations in all sampling time. In both stations, orthophosphate, ammonium nitrogen, nitrate, sulfate, and chloride analyses stayed between 3.04 and 921.1 mg/l; 0.29–619.36 mg/l; 8.94–135.04 mg/l; 125.9–1360.9 mg/l and 99.9–1249.9 mg/l, respectively, in 6 months. As a result of the characterization studies obtained from the leachate, it was found that the amounts of water entering into the waste mass and the retention period of the water in the mass were very effective in the temporal character change of the leachate. According to the Discharge Standards for Solid Waste Assessment and Disposal Facilities and Discharge to Waste Water Infrastructure Facilities of waste management regulation, the results were found to be risky. Consequently, the site in question needs to be urgently rehabilitated when considering the environmental risks of the leachate spreading from the site.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2018Scopus SJRQ1Assessment of the combined in-plane and out-of-plane behavior of brick infill walls within reinforced concrete frames under seismic loading
Onat, Onur; Correia, António A.; Lourenço, Paulo B.; Koçak, Ali
Understanding the out-of-plane response of masonry infill walls and preventing their progressive collapse mechanisms is very important for earthquake-prone countries to prevent loss of life and economic loss. In fact, having a realistic collapse mechanism assessment allows suitable prevention measures to be adopted. With this purpose in mind, two full-scale one-bay one-story substructures of reinforced concrete frames (RCF) with infill walls were tested on a shake table. These 2 specimens were designed to represent the response of a typical RC Frame at the fifth floor of an 8-story building, namely the out-of-plane failure of its infill wall under combined bidirectional seismic load. Both specimens were composed of a single-leaf clay brick infill wall surrounded by the RC Frame. However, while the first specimen corresponds to an unreinforced masonry configuration, the second specimen includes horizontal bed joint reinforcement as a strengthening/retrofitting technique. The main novelty of this study is the application of a bidirectional and simultaneous dynamic loading to the specimen, such that in-plane and out-of-plane effects are evaluated together. This work presents several interesting experimental results, with particular emphasis on the bearing capacity of the specimens against out-of-plane failure. As expected, the in-plane capacity of the reinforced infill specimen is larger than that of the unreinforced infill specimen. Nevertheless, the out-of-plane bearing capacities of the two specimens are very similar, in contrast to their ductility capacity, which is significantly increased in the reinforced masonry specimen. The capacities of the two specimens for both in-plane and out-of-plane directions, as predicted by formulations in the literature, are given. The differences found between these calculations and the results of the tests are discussed, and may possibly be explained by the parameters considered in the different formulations.
AtıfScopus49OpenAlex44İncele - MakaleYalnız künye2018Scopus SJRQ2Chemoprotective effects of curcumin on doxorubicin-induced nephrotoxicity in wistar rats: by modulating inflammatory cytokines, apoptosis, oxidative stress and oxidative DNA damage
Benzer, Fulya; Kandemir, Fatih Mehmet; Kucukler, Sefa; Comaklı, Selim; Caglayan, Cuneyt
Doxorubicin (DXR) is one of the most important chemotherapeutic agent. However, nephrotoxicity reduces its clinical utility in humans. The aim of the study was to investigate protective effects of curcumin (CMN) against DXR-induced nephrotoxicity. Rats were subjected to oral treatment of CMN (100 and 200 mg/kg body weight) for 7 days. Nephrotoxicity was induced by single intra peritoneal injection of DXR (40 mg/kg body weight) on the fifth day and then the experiment was terminated on the eighth day. Nephroprotective effects of CMN were associated with decrease in serum toxicity markers and increase in antioxidant enzyme activities. CMN was able to reduced the levels of inflammatory markers such as TNF-α, NF-κB, IL-1β, iNOS and COX-2 in the rats. It also reduced the expressions of apoptotic marker including caspase-3, and oxidative DNA damage marker including 8-OHdG. Collectively, these findings indicated that CMN protect against DXR-induced nephrotoxicity.
AtıfScopus116WoS111OpenAlex122
İncele - MakaleYalnız künye2018Scopus SJRQ4Checklist of Turkish bryophyte vegetation; [Pregled vegetacije mahovina u Turskoj]
Alataş, Mevlüt
U radu je prikazana lista vegetacijskih jedinica mahovina u Turskoj, radena prema metodologiji Braun-Blanquet- a. Ukupno je utvrdeno prisustvo 41 asocijacije i 19 subasocijacija, svrstanih u 19 sveza, 12 redova i 8 klasa. Štaviše, zabeleženo je i 6 zajednica i 17 jedinica nepoznatog fitocenološkog statusa. Briološke vegetacijske jedinice su prikazane u skladu sa njihovim akvatičnim, teresticnim i epifitskim karakterom, zajedno sa njihovim lokalitetima i sinonimima. © 2018 Institute of Botany and Botanical Garden Jevremovac, Belgrade.; A list of the known bryophyte syntaxa in Turkey compiled according to the methodology of Braun-Blanquet is presented in this study. Altogether, 41 associations and 19 subassociations belonging to 19 alliances, 12 orders, and eight bryosociological classes have been determined to date in Turkey. Moreover, six communities and 17 units of unknown phytosociological status have also been reported. The bryosociological syntaxa are grouped on the basis of their aquatic, terrestrial, or epiphytic character and given together with their localities and synonyms.
AtıfScopus9WoS5İncele - MakaleYalnız künye2018Scopus SJRQ4Epiphytic bryophyte vegetation of the Samanli Mountains (Sakarya-Kocaeli-Yalova-Bursa) in Northwest Turkey; [Epifitska vegetacija mahovina Samanli planine (Sakarya-Kocaeli-Yalova-Bursa) u severozapadnoj Turskoj]
Gözcü, Merve Can; Uyar, Güray; Alataş, Mevlüt; Ezer, Tülay; Ören, Muhammet
Epifitska vegetacija mahovina Samanli planine u severozapadnom delu Turske je istraživana na osnovu 191 snimka uzetih Braun-Blanquet metodom sa stabla drveća tokom 2015. i 2016. godine. Kao rezultat ovih istraživanja, utvrdeno je prisustvo 9 epifitskih asocijacija mahovina i 3 subasocijacije. Medu njima, 2 asocijacije i 2 subasocijacije, Neckero - Anomodontetum viticulosi, Neckero - Anomodontetum viticulosi - anomodontetosum viticulosi, Syntrichietum laevipilae, Syntrichietum laevipilae - orthotrichetosum lyellii, konstatovane su po prvi put na teritoriji Turske. Takode, epifitska vegetacija mahovina je analizirana pomoću multivarijantskih analiza, a uradene su i analize životnih formi i životnih strategija vrsta unutar vegetacijskih jedinica. Kao rezultat, dok su dugoživeće višegodišnje jedinke sa visokim reproduktivnim potencijalom dominantne u epifitskoj vegetaciji mahovina, najćešća životna forma je gusta prostirka. © 2018 Institute of Botany and Botanical Garden Jevremovac, Belgrade.; In the present study, epiphytic bryophyte vegetation of the Samanli Mountains (northwest Turkey) was investigated on the basis of 191 relevés taken from the trunks of trees by the Braun- Blanquet method between 2015 and 2016. Nine epiphytic bryophyte associations and three subassociations were determined as a result of this investigation. Among them, two associations and two subassociations, viz., Neckero - Anomodontetum viticulosi, Neckero - Anomodontetum viticulosi - anomodontetosum viticulosi, Syntrichietum laevipilae, and Syntrichietum laevipilae - orthotrichetosum lyellii, were recorded for the first time in Turkey. In addition, epiphytic bryophyte vegetation was classified and ordinated using multivariate analysis techniques such as two-way indicator species analysis and detrended correspondence analysis. Besides that, the life form and life strategies of the species within syntaxa were analysed. As a result, it is established that while perennial stayers with a high sexual reproductive effort were dominant within the epiphytic bryophyte vegetation comparatively, the most abundant life form was the mat rough type.
AtıfScopus6WoS5İncele - Derleme MakaleYalnız künye2018Scopus SJRQ3What makes us happy? Socioeconomic determinants of subjective well-being in Turkey
Birdal, Murat; Acun, Serdar; Onuk, Parla
This article explores the socioeconomic determinants of subjective well-being in Turkey based on the nationwide Turkish Statistical Institute (TURKSTAT) survey held in 2015. Our empirical results point out relationships between subjective well-being and a wide range of factors such as age, gender, marital status, education, income, financial debt, health, religiosity, employment status, type of employment, social security, crime victimization, and perception of insecurity and revealed significant gender-based disparities. Findings from this survey contribute to a broader discussion on determinants of well-being and the role of gender differences, enabling us to draw cultural comparisons.
AtıfScopus3OpenAlex2İncele - MakaleYalnız künye2018Scopus SJRQ2Effects of voltage gradient and fat content on changes of electrical conductivity of frozen minced beef meat during ohmic thawing
Cevik, Mutlu; Icier, Filiz
Frozen minced beef meat samples having different fat contents of 2, 10, and 18% were thawed until their center temperature reached −1 °C in the ohmic thawing system. Ohmic thawing was conducted by applying different voltage gradients (10, 13, and 16 V/cm) at ambient temperature of 4 ± 0.5 °C. Effective electrical conductivity (EEC) values of the samples at −1 °C were 0.5774 ± 0.0558, 0.4231 ± 0.0510, and 0.3933 ± 0.0693 S/m for 2, 10, and 18% fat contents, respectively. The change of effective electrical conductivity with temperature was linear for temperature range of −18 °C/−9.5 °C while it was exponential for temperature range of −9.5 °C/−4 °C. Above −4 °C, the polynomial model was best model describing the change of EEC with temperature. Ohmic thawing process could be applied as an alternative novel technology for thawing of meat and meat products. It is thought that the results of present study would contribute valuable information to open literature. Practical applications: Researchers have given attention on investigation of alternative thawing methods for foods in recent years. Ohmic thawing has high energy efficiency, causes low drip loss and does not produce any waste water. Since it is controlled by heat generation caused due to passing of alternative current through food, the information on change of its electrical conductivity is crucial. The minced beef sample has heterogeneous structure such as muscle, connective, and adipose tissues. Thus, its effective electrical conductivity (EEC) varies depending on its composition. In this study, the relations between temperature and EEC of minced beef samples having different fat contents were determined for four different temperature ranges existed during ohmic thawing at different voltage gradients. EEC was very low at temperatures below −4 °C, and then it sharply increased above this temperature. Results of present study would give valuable information to food industry for setting up industrial scale ohmic thawing systems for meat and meat products.
AtıfScopus52WoS47İncele - BildiriYalnız künye2018Control of fluid flow around a square prism by fluid injection at low Reynolds number
Flrat, Erhan; Tsitouras, C.; Simos, T.; King Saud University, College of Sciences, Department of Mathematics , P. O. Box 2455, Riyadh; Ural Federal University, Group of Modern Computational Methods, 19 Mira Street, Ekaterinburg
The two-dimensional wake structure behind a fixed, rigid square prism with fluid injection from the single, relatively narrow slot (h/H=0.1) has been computed at low Reynolds number (Re=ρ·U∞·H/μ=100 based on the side length of the prism and freestream velocity) using a finite volume method (FVM). Injection surface (i.e. front and rear) and injection rate (from IR=UJ/U∞=0 to 3 by 0.2 step) are the key parameters that determine the aerodynamic and flow characteristics. Two flow patterns for the prism with front jet and four flow patterns for the prism with rear jet were identified with respect to IR. Flow patterns were associated with changes in flow and aerodynamic characteristics.
AtıfOpenAlex1İncele - MakaleYalnız künye2018Scopus SJRQ2Comparison of Some Soil Fungi in Bioremediation of Herbicide Acetochlor Under Agitated Culture Media
Erguven, Gokhan Onder
In this study, we aimed to find out the biodegradation efficiency of some soil fungi types on herbicide acetochlor with acetochlor active material, chemical oxygen demand (COD), biochemical oxygen demand (BOD5) and total organic carbon (TOC) parameters. We also try to determine the population dynamics of these fungi via turbidity. The fungi cultures were isolated from agricultural field in in Thrace region of Turkey. Each fungi enriched in malt extract broth media and 1 mL of these enriched media was inoculated into 100 mL of acetochlor solutions that suggested for using application concantrations in agricultural field for farmers (11000 mg L−1) for sunflower and corn agriculture. Bioremediation results of acetochlor have shown different results according to the types of fungi. Our results indicate that Tolypocladium geodes and Cordyceps cicadae might be used in acetochlor bioremediation with a significant acetochlor, COD, TOC and BOD5 reduction and can be used for rehabilitation of agricultural fields or receiving environments for removal the opposite effects of acetochlor or other herbicides.
AtıfScopus37WoS26OpenAlex36İncele - MakaleYalnız künye2018Scopus SJRQ2Solutions of partial differential equations using the fractional operator involving Mittag-Leffler kernel
Yavuz, Mehmet; Ozdemir, Necati; Baskonus, Haci Mehmet
In this paper, time-fractional partial differential equations (FPDEs) involving singular and non-singular kernel are considered. We have obtained the approximate analytical solution for linear and nonlinear FPDEs using the Laplace perturbation method (LPM) defined with the Liouville-Caputo (LC) and Atangana-Baleanu (AB) fractional operators. The AB fractional derivative is defined with the Mittag-Leffler function and has all the properties of a classical fractional derivative. In addition, the AB operator is crucial when utilizing the Laplace transform (LT) to get solutions of some illustrative problems with initial condition. We show that the mentioned method is a rather effective and powerful technique for solving FPDEs. Besides, we show the solution graphs for different values of fractional order α, distance term x and time value t. The classical integer-order features are fully recovered if α is equal to 1.
AtıfScopus115WoS106OpenAlex131İncele - MakaleYalnız künye2018Scopus SJRQ2Dissemination of heavy-metal contamination in surface sediments of the Uzunçayır Dam Lake, Tunceli, Turkey
Kutlu, Banu
The objective of this study was to determine the heavy-metal concentrations (Cu, Pb, Zn, Ni, Mn, Fe, As, Cd, Cr, and Hg), evaluate the pollution levels, and determine the concentration of chlorophyll-a and organic carbon in the surface sediments of the Uzunçayır Dam Lake, Tunceli, Turkey, between 2015 and 2016. In order to evaluate the effect of the pollution level in the study area, the contamination factor (CF), enrichment factor, potential ecological risk index, and pollution load index were used. The concentrations of the studied heavy metals were ordered as follows: Fe > Mn > Ni > Cr > Zn > Cu > Pb > As > Cd > Hg. The highest CF value was found for the Ni element among the studied heavy metals in the Dam Lake. Moreover, the highest CF mean value was found for the As contamination level. According to the toxicity analyses in the study area, the potential toxic effect of sediments was not at a very serious level.
AtıfScopus12WoS14OpenAlex14İncele - MakaleYalnız künye2018Scopus SJRQ1Effects of salicylic acid and organic selenium on wheat (Triticum aestivum L.) exposed to fenoxaprop-p-ethyl
Akbulut, Gulcin Beker; Yigit, Emel; Kaya, Armagan; Aktas, Aydın
In this study, we evaluated effects of fenoxaprop-p-ethyl herbicide on wheat (Triticum aestivum L.). The wheat plants were grown in pots containing perlite. Fenoxaprop-p-ethyl was applied to adequately grown T. aestivum plants at determined doses (1 mM, 1.5 mM, 2.2 mM, 3.4 mM and 5.1 mM) via spraying. The effects of this herbicide on some antioxidant enzymes, lipid peroxidation, carotenoid, total chlorophyll and total phenolic were investigated on days 1, 5 and 10 following the application. Environmental pollutants cause oxidative stress, production of free radicals and changes in antioxidants. Synthesis of signal molecules such as salicylic acid (SA) is important for the stress response of plants. In addition to this, although selenium is known not to be an obligatory element for plants, low dose selenium has positive effects on the plant growth. We also investigated the effects that are elicited on parameters above mentioned by the treatment of exogenous 0.5 mM SA and 0.004 mM organic selenium (SeI) separately. Our findings reveal that SA and SeI, which are externally applied before the germination of seeds that are exposed to herbicide stress, becomes effective in reduction of the negative effects of fenoxaprop-p-ethyl, with regard to antioxidant system, lipid peroxidation, pigment system and total phenolic. When we evaluate the study results, our findings suggest that especially SA plays a protective role on wheat against herbicide stress.
AtıfScopus21WoS19OpenAlex24İncele - MakaleYalnız künye2018Scopus SJRQ1Transmission line fault location using traveling wave frequencies and extreme learning machine
Akmaz, Düzgün; Mamiş, Mehmet Salih; Arkan, Müslüm; Tağluk, Mehmet Emin
In this research, a new approach was proposed for determining the fault location in transmission lines. Traveling wave frequencies and an extreme learning machine (ELM) were used to determine fault location. Transient signals in the time domain were transformed to the frequency domain using the fast Fourier transform (FFT) and the traveling wave frequencies were detected from the transient frequency spectrum. In order to detect the location of fault, traveling wave frequency was used initially to predict the fault location. The prediction of this fault location was tested for many different fault conditions and was found to be adversely affected by only the source inductance value. This is due to the negative effect of source inductance on wave velocity. Regression feature of ELM was used in order to improve the prediction of fault location and to minimize the negative effect of source inductance. For ELM regression training, values of the fault distance estimated from the traveling-wave frequencies and the source inductance values were used as ELM input data, and the actual distance values were used as ELM output data. After ELM regression training, ELM predicted a new fault location using the input data. The Alternative Transients Program (ATP/EMTP) was used to model J. Marti frequency dependent line model, and the MATLAB program was used to perform fault-detection algorithms. Simulation results show that the proposed method is very successful against many variables such as different fault resistances, source inductances, transmission line characteristics, transmission line lengths.
AtıfScopus104WoS74OpenAlex101İncele - MakaleYalnız künye2018Scopus SJRQ2Curing effect on mortar properties produced with styrene-butadiene rubber
Cemalgil, Selim; Etli, Serkan; Onat, Onur
This paper presents an experimentally investigation pertinent to the mechanical properties of rubberized mortar (RM) with styrene-butadiene rubber (SBR). The SBR were used with constant water-to-cement ratio of 0.485 and two different volume proportion of SBR particles were utilized as aggregates. One types of SBR particles with fineness modulus of 4.951 were utilized 0%, 10%, and 20% of aggregate volume. Effectiveness of SBR replacement ratio, curing and aging effect on the compressive strength, flexural strengths as well as load-displacement. Compressive and flexural strength of concrete were investigated at the end of 28-days and 56-days age. Obtained results demonstrated that utilization of SBR reduced the flexural strength of SBR mortar at the earlier curing age while SBR increased. Moreover, mechanical properties of mortar mentioned above were significantly affected by the water cure timing with an increasing proportion of the replacement level of SBR.
AtıfScopus11WoS11OpenAlex13İncele - MakaleYalnız künye2018Scopus SJRQ2New results on nondensely characterized integrodifferential equations with fractional order
Ravichandran, C.; Jothimani, K.; Baskonus, Haci Mehmet; Valliammal, N.
This study reports a novel approach which deals with the coupled classes of fractional integrodifferential equations for nondensely characterized linear operators in the Banach space. Using the noncompact measure theory, we investigate the existence of the results presented.
AtıfScopus69WoS65OpenAlex77İncele - MakaleYalnız künye2018Scopus SJRQ4400 MHz NMR Study of Isotope Effects on Albumin in H2O/D2O Solutions
Korunur, S.; Zengin, B.; Yılmaz, A.
Abstract: Chemical shift measurements were performed for several percentages of H2O added to D2O, in several H2O/D2O mixtures without and with a single concentration of albumin, and also in a mixture of 0.1H2O/0.9D2O containing increasing concentrations of albumin. The chemical shifts of pure mixtures decreases with increasing fraction of pure water. This is closely related to isotope effects. The chemical shift corrected for isotope effects increases with percentage of H2O. The chemical shift obtained for the mixture of 0.1H2O/0.9D2O increases with increasing concentration of albumin. These increments are consistent with fast chemical exchange in H2O/D2O mixture. In conclusion, present study reveals the presence of isotope effect on albumin in H2O/D2O solutions, and demonstrates fast chemical exchange in D2O solutions with albumin in a different way.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2018Scopus SJRQ2Microbial Sorption of Uranium Using Amycolatopsis sp. K47 Isolated from Uranium Deposits
Celik, Fatih; Camas, Mustafa; Kyeremeh, Kwaku; Sazak Camas, Anil
The increasing contamination of soils, sediments, and water with heavy metals through natural and industrial processes is a worldwide problem. Mining processes produce tons of material contaminated with radionuclides such as U and different heavy metals such as Cd, Ni, and Pb. U(VI) adsorbs strongly on bacteria, exhibiting pH-dependent adsorption behavior that is caused by a range of uranyl surface complexes on bacteria cell walls. The Amycolatopsis sp. K47 was isolated from Manisa Koprubasi Kasar open-cast uranium mine and identified for the first time. Using the batch adsorption method, the biosorption potential of this microbe was investigated by studying the effects of changes in pH (1–10), biomass dose (0.1–5 g/l), initial uranium metal concentration (5–200 mg/l), contact time (5–180 min), and temperature (20–60 °C). Interpretation of FTIR data obtained for both the uranium loaded and unloaded Amycolatopsis sp. K47 biomass showed the presence of carboxylic acid, hydroxyl, and amide functional groups that could interact with uranium ions. Scanning electron microscopy images demonstrated that uranium was intensely adsorbed on the microbial biomass surface. The sorption isotherms were investigated by analysis of the Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) models. The Langmuir isotherm model was found to show the best fit for the experimental data obtained. Furthermore, thermodynamic parameters, such as ΔH°, ΔS°, and ΔG°, were calculated using adsorption equilibrium constant obtained from the Langmuir isotherm. The optimal experimental conditions were determined to be pH = 4, C0 = 40 ppm, t = 150 min, temp. = 40 °C, and abs. dose = 1 g/l, and the corresponding U(VI) removal efficiency was about 97 ± 2%.
AtıfScopus16WoS14OpenAlex15İncele - MakaleYalnız künye2018Scopus SJRQ3Holographic reconstruction of scalar fields in extended Kaluza Klein cosmology
Korunur, Murat
In recent years, many studies have been conducted to reconstruct the physical properties of scalar fields by establishing a connection between some energy densities and a scalar field of dark energies. In this paper, using the extended five-dimensional (5D) Kaluza- Klein model, we establish a correspondence among modified holographic dark energy and the tachyon, K-essence and dilaton scalar-field models. We also graphically illustrate the evolution of the equation-of-state parameter versus time.
AtıfScopus7WoS7OpenAlex7İncele - MakaleYalnız künye2018Scopus SJRQ2Preliminary geochemical data of the mafic rocks from the ovacik and Pülümür ophiolite zone (Eastern Anatolia, Turkey): Implications for the geodynamic evolution of the northern neotethyan ocean
Çimen, Okay; Önal, Ayten Öztüfekçi
The İzmir-Ankara-Erzincan-Sevan-Akera Suture Belt (IAESASB) stretches from the Aegean Sea to the Lesser Caucasus and includes the remnants of the Northern Neotethys. The Ovacık and Pülümür Ophiolite Zone (OPOZ) to the north of Tunceli is less-known members of this belt. In this study, preliminary geochemical data from the basaltic and gabbroic rocks from this zone are presented to provide the first insights into their geochemistry. The studied mafic samples exhibit geochemical characteristics of an intra-oceanic subduction system. Three types of samples were differentiated on the basis of their major, trace and rare earth element (REE) geochemistry. The first one is boninitic and displays highly depleted elemental pattern (relative to N-MORB) and concave REE profile. The second type is akin to back-arc basin basalts (BABB) and generally reflects normal-MORB (NMORB)-like high field strength element (HFSE) patterns coupled with negative Nb anomalies. The last type is relatively similar to the BABB-type, but it lacks the marked negative anomaly in Nb and can be ascribed to the mid-ocean ridge basalt (MORB). The overall geochemical features suggest that these mafic rocks were predominantly generated in a supra-subduction setting from a subduction-modified mantle source. It is further suggested that the Ovacık and Pülümür Ophiolite Zone was formed in an oceanic arc-basin system within the northward subducting Northern Neotethys.
AtıfScopus7İncele