Yazarlar
- Tanyol, Mehtap(22)
- Yildirim, Numan(17)
- Karataş, Mehmet(14)
- Erguven, Gokhan Onder(13)
- Topal, Murat(13)
- Ince, Muharrem(12)
- Yildirim, Nuran Cikcikoglu(10)
- Kismet, Yilmaz(9)
- Öbek, Erdal(8)
- Arslan Topal, E. Işıl(7)
- Etli, Serkan(7)
- Goksu, Ali(7)
- Gul, Muhammet(7)
- Gülmez, Nihan(7)
- Ogedey, Aysenur(7)
- Uysal, Turan(7)
- Yonten, Vahap(7)
- Gürler, Nedim(6)
- Kaya, Sema Kayapinar(6)
- Sabanci, Serdal(6)
- Serdar, Osman(6)
- Yön, Merve Şahin(6)
- Alp, Hevidar(5)
- Aydoğmuş, Ercan(5)
- Benli, Ahmet(5)
- Cemalgil, Selim(5)
- Erdemoğlu, Murat(5)
- Erust, Ceren(5)
- Ince, Olcay Kaplan(5)
- Oguz, Ensar(5)
- Torğut, Gülben(5)
- Yilmaz, Mehmet(5)
- Yucesan, Melih(5)
- Celik, Erkan(4)
- Demir, Veysel(4)
- Dener, Murat(4)
- Doğan, Akar(4)
- Fırat, Tülay(4)
- Pekdemir, Mustafa Ersin(4)
- Tanaydin, Mehmet Kayra(4)
Yayınlar
- MakaleYayıncıda açık erişim2019Scopus SJRQ3An integrated best-worst and interval type-2 fuzzy TOPSIS methodology for green supplier selection
Yucesan, Melih; Mete, Suleyman; Serin, Faruk; Celik, Erkan; Gul, Muhammet
Supplier selection is one of the most important multi-criteria decision-making (MCDM) problems for decision-makers in the competitive market. Today's organizations are seeking new ways to reduce the negative effects they have on the environment and to achieve a greener system. Currently, the concept of green supplier selection has gained great importance for its ability to incorporate environmental or green criteria into classical supplier selection practices. Therefore, in this study, a multi-phase MCDM model based on the best-worst method (BWM) and the interval type-2 fuzzy technique for order preference by similarity to ideal solution (IT2F TOPSIS) is proposed. A case study in a plastic injection molding facility in Turkey was carried out to show the applicability of the proposed integrated methodology. The paper offers insights into decision-making, methodology, and managerial implications. Results of the case study are examined and suggestions for future research are provided.
AtıfScopus93WoS85OpenAlex98
İncele - MakaleYalnız künye2018Scopus SJRQ1Physical properties of structural soils containing waste materials to achieve urban greening
Yilmaz, Deniz; Cannavo, Patrice; Séré, Geoffroy; Vidal-Beaudet, Laure; Legret, Michel; Damas, Olivier; Peyneau, Pierre-Emmanuel
AtıfOpenAlex75İncele - MakaleYayıncıda açık erişim2018Scopus SJRQ1Investigation of usability of limonite aggregate in heavy-weight concrete production
Esen, Yuksel; Dogan, Zulfu Murat
Limonite (Fe2O3.xH(2)O) is a soft or brown, hard iron mineral, usually in yellow colour. It is also used as a pigment since it contains iron ore. It is believed that it can also be used in the production of heavy concrete due to its 60% iron ore content. In this paper, an experimental study was carried out on radiation shielding properties and certain physical and mechanical properties of normal and limonite reinforced concrete. For this purpose, with the normal concretes prepared according to standards, amounts of aggregates were reduced at the rates of 20%, 40%, 60%, 80% and 100% by volume respectively, and heavy concrete mixes were prepared that were obtained by adding limonite at the same rates in their place. With limonite reinforcement, compressive and flexural strength of the concrete produced decreased, water absorption amount increased and their radiation permeability significantly decreased.
AtıfWoS54OpenAlex56İncele - MakaleYalnız künye2018Scopus SJRQ3Kinetics behavior of methylene blue onto agricultural waste
Sarici-Özdemir, Cigdem; Kiliç, Fatih
In the present work, investigations on a potential use of agricultural waste for the removal of methylene blue (MB) from wastewater are presented. Adsorption kinetics of MB has been studied using reaction-based and diffusion-based models. Three kinetic models, namely pseudo-first-order, pseudo-second-order, and the Elovich are analyzed at the temperature of 298 K for the reaction-based model. The kinetic studies showed that the data were well described by the pseudo-second-order kinetic model. Intraparticle diffusion, external-film diffusion, and internal-pore diffusion models characterizing MB were obtained. The results suggested that the agricultural waste has a high potential to be used as an effective adsorbent for MB adsorption. Pseudo-first-order, pseudo-second-order, and the Elovich models were employed to describe the desorption mechanism. The experimental results showed that the pseudo-second-order equation is the best model.
AtıfWoS22OpenAlex23İncele - MakaleYalnız künye2018Scopus SJRQ1Antioxidant biomarkers in Gammarus pulex to evaluate the efficiency of electrocoagulation process in landfill leachate treatment
Serdar, Osman; Yildirim, Nuran Cikcikoglu; Tatar, Sule; Yildirim, Numan; Ogedey, Aysenur
The discharge of landfill leachate into the environment without effective treatment poses a serious threat for the aquatic ecosystems. This present study was undertaken to evaluate whether electrocoagulation process is efficient for treatment landfill leachate (LL) or not by using antioxidant biomarkers in Gammarus pulex. Glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities and malondialdehyde (MDA) and glutathione (GSH) levels in G. pulex exposed to untreated, treated, and diluted rates 1/10 and 1/20 in both LL during 24 and 96 h were tested. Physiochemical characteristics of leachate (chemical oxygen demand, electrical conductivity, pH, phosphate, turbidity, NH3, Cl−, and color) were determined pre and post treatment. All physiochemical characteristics of LL decreased after treatment process. GSH-Px and CAT activities and GSH and MDA levels were increased in untreated groups when compared to control (p < 0.05). After treatment by electrocoagulation, MDA and GSH levels and CAT activities were returned to control values. In conclusion, the abilities of LL to stimulate oxidative stress in G. pulex have been proven. The results revealed that antioxidant parameters are useful biomarkers for determining the treatment efficiency of the electrocoagulation process.
AtıfScopus19WoS17OpenAlex23
İncele - MakaleYalnız künye2018Scopus SJRQ2Assessment of pollution potential of the Hasangazi chromite pit (Tunceli, Turkey): implications for the natural environment
Çimen, Okay; Öztüfekçi Önal, Ayten; Akyol, Eylem Akarsu
The Hasangazi chromite pit is an abandoned mine located to the east of the town of Pülümür (Tunceli, Turkey). The surface water that circulates in the pit flows into the Pülümür stream via the Turnadere creek. The quality of the surface water and soil from the region is important regarding the ecosystem in the Tunceli area. The open pit operations in the chromite deposits may be the cause of toxic element enrichments. To understand the effects of such pits, samples from the sediments, soil, waste material, and surface water were collected from the Hasangazi pit and its surrounding area. Samples were mineralogically and geochemically analyzed by XRD, ICP-OES, and ICP-MS methods. Mineralogical analyses showed the presence of chrysotile and plagioclase in the sediment and soil samples. These samples are also enriched in toxic elements, e.g., Cr, Ni, and Co. In particular, the Cr and Ni concentrations exceed the limits of soil pollution regulation of Turkey and the US Environmental Protection Agency. Overall the Cr, Ni, and chrysotile contents demonstrate the impact of the abandoned pit and the ultramafic rocks. Moreover, the surface water samples in the dry season have Zn concentrations above the toxic levels that may have been derived from the volcanic rocks. Environmental remediation precautions should immediately be taken around this inactive pit.
AtıfScopus6WoS6OpenAlex8İncele - MakaleYalnız künye2018Scopus SJRQ2COD removal from leachate by electrocoagulation process: Treatment with monopolar electrodes in parallel connection
Tanyol, Mehtap; Ogedey, Aysenur; Oguz, Ensar
This study examines the removal of chemical oxygen demand (COD) from landfill leachate generated from the municipal landfill site of Bingol, Turkey. The effect of parameters such as current density, pH, and inter-electrode distance during the electrocoagulation (EC) process on COD removal of the process was investigated. Moreover, for COD removal, the energy consumption and operating costs were calculated for iron electrode under the EC conditions. COD removal efficiency was 72.13% at the current density of 16 mA m-2, pH of 8.05, and the inter-electrode distance of 9 mm at the detention time of 60 min with iron electrode and the COD concentration was reduced from 6,100 mg L-1 to 1,700 mg L-1 by EC. The highest value of the electrical energy and electrode consumptions per kg of COD in the optimum conditions were determined as 0.055 kWh kg-1 COD and 3.43 kg kg-1 COD and the highest operating cost value was found to be 1.41 US$ kg-1 COD for 0-60 min time intervals.
AtıfScopus29WoS29OpenAlex32İncele - MakaleAçık Erişim2018Scopus SJRQ3The chemical and biochemical oxygen demand reduction by armillaria tabescens in malathion supplemented culture medium
Yildirim, N.; Erguven, G.O.; Adar, E.
The extensive use of pesticides for controlling insects has been widely used in agricultural activities. However, the indiscriminate use of the pesticides has inflicted serious harmful problems to humans in the ecosystem. Our study aims to evaluating the capacity of Armillaria tabescens to remove the chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) at different concentration of malathion insecticide (50, 100 and 150 ppm) under agitated (130 rpm) submerged culture conditions at 27 °C after 8 and 15 days. According to our results, A. tabescens has achieved COD reduction as 52.39, 27.24, and 38.30% at concentration of 50, 100 and 150 ppm respectively on 15 days. The BOD5 reduction rates were found as 78.2, 74.76 and 81.26% at 50, 100 and 150 ppm concentration respectively at the end of the 15th days. At the end of this time period, the dried biomass of A. tabescens was weighted and we have suggested that malathion in medium reduced the biomass production compared the control group (Sabouraud dextrose broth + A. tabescens). Our experiments have focused that; A. tabescens could be an alternative and useful fungus for bioremediation of wastewater containing malathion insecticide.
AtıfScopus3WoS3OpenAlex4İncele - MakaleYalnız künye2018Scopus SJRQ2Mechanical and flow properties of blends of polypropylene and powder coating recyclates with and without addition of maleic anhydride
Kismet, Yilmaz; Wagner, Manfred H.
In this research, from 10% to 40% by weight of hydrolyzed powder coating recyclates were used as filler in polypropylene (PP). Firstly, PP and filler were dry-mixed and then, in order to get a homogeneous mixture, were extruded at 180°C. The resulting compounds were cooled and granulated, and by use of an injection molding machine at 180–200°C, standard tensile test bars were produced. Tensile stress, three-point bending strength, and izod impact strength of these specimens containing different types of filler and different filler concentrations were tested. The results are presented, and the effects of type and content of hydrolyzed powder coating waste on the mechanical properties of polypropylene are discussed. Also, the change in melt flow index of polypropylene as a function of filler content is analyzed. Furthermore, the bonding mechanism of filler and matrix material was examined by electron microscopy.
AtıfScopus12WoS10OpenAlex13İncele - 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 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 - MakaleAçık Erişim2018Scopus SJRQ2Comparative Adsorption of Different Dyes from Aqueous Solutions onto Polymer Prepared by ROP: Kinetic, Equilibrium and Thermodynamic Studies
Torğut, Gülben; Demirelli, Kadir
Poly(1,2-epoxy-3-phenoxy)propane was synthesized by ring-opening polymerization using Sn (Oct) 2 as a catalyst and benzyl alcohol as an initiator. Homopolymer’s epoxy type was acylated with chloroacetyl chloride firstly and then modified with the diethanol amine. The polymers were characterized by FT-IR and 1H - NMR. Dye adsorption properties of poly(2-phenoxy ethyl [bis(2-hydroxy ethyl)amino]acetate) were investigated by using bromocresol green (BCG), alizarin yellow (AY) and methylene blue (MB). Amounts of dye holding polymers at different times were calculated and plotted as a function of time. According to the removal results, all of the dyes reach its highest efficiency at 90 min. The effect of pH on adsorption of dyes was studied in the pH range of 2–11. Kinetic models known as pseudo-first order and pseudo-second order were used to analyze the mechanism of adsorption, and the results indicated an adsorption kinetic compatible with the pseudo-second order. The Langmuir and Freundlich isotherms were utilized to explain the adsorption equilibrium, and when it was compared with each other, it was revealed that the Langmuir isotherm model was better than Freundlich isotherm. The maximum adsorption capacities of BCG, AY and MB were 52.63, 15.87 and 31.25 mg/g, respectively. Furthermore, thermodynamic properties (Δ H∘, Δ S∘, Δ G∘) of modified polymer were investigated for the three dyes. According to the thermodynamic parameters, the adsorption of the dyes occurred spontaneously and was endothermic. The results of this study support that novel polymer, an inexpensive and effective adsorbent, could be used for dye removal from aqueous solutions.
AtıfScopus20WoS16OpenAlex24İncele - MakaleYalnız künye2017Scopus SJRQ3Enhancing the potential of employing thermosetting powder recyclates as filler in LLDPE by structural modifications
Kismet, Yilmaz; Wagner, Manfred H.
Potential of using powder coating recyclates as filler material for polyethylene compounds was investigated. Due to their strong adhesion to the metal surface during compounding at extrusion temperatures higher than 100 degrees C, the coating powder recyclates were chemically modified to facilitate its processing by extrusion and injection molding at higher temperatures. For this purpose, the coating powder recyclates were first hydrolyzed with addition of an alcohol as swelling agent. The deactivated recyclates were mixed at different ratios with the matrix polymer, a linear low-density polyethylene (LLDPE). The mixtures obtained were then compounded by extrusion and subsequently injection molded to plates to produce specimens for testing. The resulting samples were characterized mechanically by tensile, bending, and impact strength tests. In summary, the powder coatings recyclates can be processed as filler for thermoplastic material, without any adhesion problems up to 160 degrees C and 180 degrees C in the extruder and in the injection molding machine, respectively.
AtıfWoS12OpenAlex13İncele - Derleme MakaleAçık Erişim2017Usage of microalgae as a sustainable food source in aquaculture
Özçiçek, Esin; Cane, Erkan; Yilmaz, Kadir; Can, Safak Seyhaneyildiz
The need for food sources more reliability according to animal products has increased interest especially in plants and in algae. In aquaculture has benefited significantly from microalgae in the various application areas. They are used as food as well as are evaluated as sources of pigments in the salmonids. Currently, studies are underway to examine the cost-effectiveness of microalgae production systems which can be obtained by large-scale and advanced quality control. In order to ensure sustainability in the use of microalgae; a systems based approach is needed which integrates different fields such as biotechnology, bioprocess and management procedures.
AtıfWoS4OpenAlex1İncele - MakaleYalnız künye2017Scopus SJRQ1A food waste utilization study for removing lead(II) from drinks
Ince, Olcay Kaplan; Ince, Muharrem; Yonten, Vahap; Goksu, Ali
This is the first study about removal of lead (Pb(II)) from energy drinks. In this paper, food waste, namely eggshell (hydroxyapatite) utilization, was used to remove Pb(II) from mineral water and energy drinks. Mineral water and energy drinks were chosen for removal of lead since the latter is severely hazardous to human health even in small amounts. Response Surface Methodology (RSM) was performed to optimize the application process by practice of the quadratic model united with the Central Composite Design (CCD) and quadratic combined program was utilized to study the most effective parameters on aforementioned liquids. Through the application of variance analysis (ANOVA) factors critical to removing of lead were identified for each experimental design response. Maximum adsorption capacity of eggshell was achieved as 923 mg g(-1) for Pb(II). The obtained optimum conditions were applied to drinks. Results showed that used adsorbent was quite effective in removing Pb(II) from drinks. (C) 2016 Elsevier Ltd. All rights reserved.
AtıfWoS27OpenAlex28İncele - DüzeltmeYalnız künye2017Scopus SJRQ1A food waste utilization study for removing lead(II) from drinks (vol 214, pg 637, 2017)
Ince, Olcay Kaplan; Ince, Muharrem; Yonten, Vahap; Goksu, Ali
- MakaleYalnız künye2017Scopus SJRQ1Performance analyses for evaporation of pomegranate juice in ohmic heating assisted vacuum system
Cokgezme, Omer Faruk; Sabanci, Serdal; Cevik, Mutlu; Yildiz, Hasan; Icier, Filiz
AtıfOpenAlex83İncele - MakaleAçık Erişim2017Scopus SJRQ1Evaluation of physical and mechanical characteristics of siderite concrete to be used as heavy-weight concrete
Esen, Yuksel; Dogan, Zulfu Murat
The objective of this study is to investigate the usability of siderite aggregates mentioned above as a heavy-weight aggregate in the heavy-weight concrete production and their effects on physical properties of the heavy-weight concrete mixture. For this purpose, normal-weight aggregate content was decreased at the rate of 20%, 40%, 60%, 80% and 100% by volume of the concrete mixture prepared and mixtures were prepared by its substitution with siderite aggregate at the same rates. Based on the increase in siderite aggregate in the concrete mixture, a considerable increase in unit weight, compressive strength and tensile strength of concrete was obtained. Plate-shaped concrete specimens obtained from combined normal-weight and heavy-weight aggregates were exposed to radiation with different X-ray source (118 keV, 164 keV) and Co-60 (1250 keV) beam source at cekmece Nuclear Facility. It is clearly seen that the concrete mixture containing siderite aggregate improved 70% radiation absorption characteristics compared to that of the concrete mixture without siderite aggregate. (C) 2017 Elsevier Ltd. All rights reserved.
AtıfWoS53OpenAlex51İncele - MakaleYalnız künye2017Scopus SJRQ3Hazardous Waste Management in Turkey
Akkoyunlu, Atilla; Avsar, Yasar; Erguven, Gokhan Onder
The objective of this study is to analyze the time processes of hazardous waste management (HWM) in Turkey. There should be a holistic evaluation of a country's hazardous waste management program in terms of theoretical qualifications, best practice applications, and, of course, problems and their solutions. This paper offers a similar approach to evaluate HWM in compliance with the European Union under the laws of environmental applications. In 2010, 786,418 tons of hazardous waste (HW) were produced in Turkey. Of this, around 18% is sent to municipal garbage dumps, 0.6% is burned, and the remaining 81.4% is disposed of by other methods (such as controlled landfill or haphazard throwaways). (C) 2017 American Society of Civil Engineers.
AtıfWoS6OpenAlex10İncele - Kitap BölümüAçık Erişim2017Use of FAHP for occupational safety risk assessment: An application in the aluminum extrusion industry
Gul, Muhammet; Guneri, Ali Fuat
Risk is dened as relating to a technical or sociotechnical system in which events may take place in the future that have unwanted consequences to assets that we want to protect (Rausand, 2011). The rst stage in controlling risks is to perform a risk assessment in order to see what is required to be done (Health and Safety Executive, 1998). This includes identifying hazards, deciding the harmfulness of them, evaluating all possible risks, reducing them, and recording the results, respectively (Health and Safety Executive, 1998; Main, 2004; Gul and Guneri, 2016). The plentifulness in risk assessment.
AtıfScopus11OpenAlex149İncele
