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
- MakaleAçık Erişim2016Scopus SJRQ3Uranium (VI) Biosorption on Marine Sponge, Sarcotragus foetidus (Schmidt, 1862) and Its Statistical Investigation Using Central Composite Design
Celik, Fatih; Camas, Mustafa; Camas, Anil Sazak; Ozalp, Hasan Baris
The biosorption of heavy metals, radionuclides, uranium and thorium for the recovery or removal from aqueous systems using various micro-organisms and biological substances has been investigated by several groups of workers. In this paper, the uptake of uranium (VI) from aqueous systems by a marine sponge, Sarcotragus foetidus (Schmidt, 1862) has been investigated. S. foetidus samples were collected from Babakale/Ayvacik/Canakkale in Turkey. Uranium (VI) uptake experiments were carried out by the batch technique. The affecting parameters were analyzed using Central Composite Design (CCD) as the experimental method. Four independent variables such-pH, temperature, contact time, and initial uranium concentration were selected for this study. The influences of initial pH, contact time, and initial uranium concentration on the biosorption process were considered statistically significant as main effects. On the other hand, interaction effects of pH and contact time, as well as pH and initial uranium concentration, were considered as significant parameters on the biosorption process. The optimum condition of biosorption process was found to be at initial pH: 4, temperature: 35 degrees C, initial uranium concentration: 20 mg/L, and contact time: 31 minutes. At these conditions, the biosorption yield of uranium (VI) ions was obtained to be 93.29 +/- 2%.
AtıfWoS2OpenAlex1
İncele - MakaleYalnız künye2016Scopus SJRQ3The capacity of some newly bacteria and fungi for biodegradation of herbicide trifluralin under agiated culture media
Erguven, G. O.; Bayhan, H.; Ikizoglu, B.; Kanat, G.; Nuhoglu, Y.
Bioremediation is the use of microorganisms to degrade environmental contaminants (pesticides, polyaromatic hydrocarbons etc.) into less toxic forms or compounds. In this study microbial biodegradation of trifluralin was performed in liquid media with 11 different types of identified fungi and bacteria cultures and their mixtures in agiated culture media. The isolated fungi and bacteria mixtures showed the highest degradation, reaching 93% in the chemical oxygen demand (COD) parameter in four days and 82% as trifluralin active ingredient in five days. Bacteria and fungi mixtures achieved 69% and 66% degradations of trifluralin active ingredient respectively. In the fungi studies, the best removal was achieved by M. Chlamydosporia at 80%, in the bacteria studies, the best removal was achieved by Bacillus simplex about 95% in five days. These different removal rates were due to the microbial differencies.
AtıfWoS16OpenAlex2
İncele - MakaleAçık Erişim2016Scopus SJRQ1Hardness removal from waters by using citric acid modified pine cone
Altundogan, Hamdi Soner; Topdemir, Aykut; Çakmak, Meltem; Bahar, Nurdan
In this study, an effective cation exchanger was developed from the pine cone by citric acid modification and its hardness removal properties from the waters were investigated. For this purpose, ground pine cone samples were subjected to a citric acid modification following NaOH saponification. Both of the raw (RPC) and modified pine cone (MPC) samples were subjected to standardized hardness removal tests by shaking with hard waters. These tests showed that citric acid modification significantly increases the cation exchange capacity of the pine cone. Most suitable size fraction of pine cone was determined as -16 + 30 mesh (600 mu m < x < 1200 mu m). Also, citric acid modified product obtained from this fraction was used in a continuous system to remove hardness from water. The results of this study showed that the MPC can be used for hardness removal from waters as a cheap, durable and environment -friendly material. Finally, regeneration experiments showed that the MPC can be used for hardness removal from water repeatedly by a simple HCl regeneration. (C) 2015 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
AtıfWoS28OpenAlex34İncele - MakaleYalnız künye2016Scopus SJRQ3Experimental and modeling studies of methylene blue adsorption onto particles of peanut shell
Kiliç, Fatih; Sarici-Özdemir, Cigdem
In this study, adsorption of methylene blue from aqueous solution onto peanut shell has been investigated. Experimental data obtained from dye adsorption have been studied by five two-parameter (Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, and Frumkin) and five three-parameter (Redlich-Peterson, Sips, Toth, Radke-Prausnitz, and Koble-Corrigan) isotherm models. Eight nonlinear error functions (sum squares errors, hybrid fractional error function, Marquardt's percent standard deviation, average relative error, sum of absolute error, the coefficient of determination, nonlinear chi-square test, and standard deviation of relative errors) were examined for isotherm equations. In order to explain the adsorption kinetics fit of pseudo-first-order, pseudo-second-order, Elovich, and intraparticle kinetic models were used. The best fitting isotherm model was the Radke-Prausnitz and kinetics model was pseudo-second-order. Adsorption experiment showed that the maximum capacity of agricultural waste for methylene blue was 67.57 L.g(-1) at 25 degrees C.
AtıfWoS7OpenAlex8İncele - MakaleYalnız künye2015Scopus SJRQ1Biochemical response of crayfish Astacus leptodactylus exposed to textile wastewater treated by indigenous white rot fungus Coriolus versicolor
Aksu, Onder; Yildirim, Nuran Cikcikoglu; Yildirim, Numan; Danabas, Durali; Danabas, Seval
The discharge of textile effluents into the environment without appropriate treatment poses a serious threat for the aquatic organisms. The present study was undertaken to investigate biochemical response of crayfish Astacus leptodactylus exposed to textile wastewater (TW) treated by indigenous white rot fungus Coriolus versicolor. Glutathione S-transferase (GST), cytochrome P450 1A1 (CYP1A1), and acetylcholinesterase (AchE) levels in hepatopancreas and abdomen tissues of crayfish exposed to untreated, treated, and diluted rates (1/10) in both TW during 24 and 96 h were tested. Physiochemical parameters (electrical conductivity (EC), chemical oxygen demand (COD), pH, and total dissolved solid (TDS)) of TW were determined before and after treatment. Physiochemical parameters of TW decreased after treatment. The GST activity and AchE were generally increased, but CYP1A1 activity was decreased in hepatopancreas tissue of crayfish exposed to different kinds of untreated TW. After treatment by indigenous white rot fungus (C. versicolor), GST and CYP1A1 activities were returned to control values, while AchE activities were increasing further. In this study, only GST and CYP1A1 activities of A. leptodactylus confirmed the efficiency of TW treatment with C. versicolor.
AtıfWoS23OpenAlex27İncele - MakaleYalnız künye2015Scopus SJRQ2Removal of Phosphate from Aqueous Solutions by Chemical- and Thermal-Modified Bentonite Clay
Tanyol, Mehtap; Yonten, Vahap; Demir, Veysel
The study investigated phosphate adsorption from aqueous solutions using chemical- and thermal-modified bentonite in batch system. The adsorbent was characterized by SEM, BET, and FTIR spectroscopy. Contact time, beginning phosphate concentration, pH of the solution, and the effects of the temperature on phosphate adsorption capacity were determined by a series of experimental studies. In a wide pH range (3-10), high phosphate removal yields were obtained (between 94.23 and 92.26 %), and with the increase in temperature (from 25 to 45 degrees C), phosphate removal increased. Langmuir and Freundlich isotherms were used to determine the sorption equilibrium, and the results demonstrated that equilibriumdata displayed better adjustment to Langmuir isotherm than the Freundlich isotherm. Phosphate sorption capacity, calculated using Langmuir equation, is 20.37 mg g(-1) at 45 degrees C temperature and pH 3. Mass transfer and kinetic models were applied to empirical findings to determine the mechanism of adsorption and the potential steps that control the reaction rate. Both external mass transfer and intra-particle diffusion played a significant role on the adsorption mechanism of phosphate, and adsorption kinetics followed the pseudo-second-order-type kinetic. Furthermore, thermodynamic parameters (Delta H degrees, Delta G degrees, Delta S degrees) which reveal that phosphate adsorption occur spontaneously and in endothermic nature were determined. The results of this study support that bentonite, which is found abundant in nature and modified as an inexpensive and effective adsorbent, could be used for phosphate removal from aqueous solutions.
AtıfWoS26OpenAlex27İncele - MakaleYalnız künye2013Scopus SJRQ1Geo-environmental site investigation for Tunceli, Turkey municipal solid waste disposal site
Önal, Ayten Oztufekci; Demirbilek, Deniz; Demir, Veysel
The environmental and geological condition of a current solid waste disposal site in the city of Tunceli, Turkey was investigated. Improper geological structure and soil properties of this unsanitary solid waste storage site as well as leachate from this site caused significant pollution in air, soil, and surface water. Natural soil characteristics and geology of the site are presented in this paper. Petrographic properties of vulcanized rubber rocks composed of tuff and volcanic sandstone at the bottom of storage sites and the mineralogical composition of the base composed of these rocks were examined. Permeability of the natural soil and index properties were determined using soil mechanics experiments (moisture content, specific gravity, Atterberg limit tests, sieve analysis, hydrometer analysis, falling-head permeability test, and standard proctor test) conducted on disturbed samples collected from excavated sites and the relationship between mineralogical composition and soil hydraulic behavior was investigated. Natural soil samples of six different parts of the site indicated that, the soil class in four samples is silty sands, sand-silt mixtures, one is clayey sands, sand-clay mixtures and one is clayey silts with slight plasticity. The values obtained using permeability tests for subsoil samples vary from 10(-5) to 10(-8) cm/s. Low permeability (10(-7) and 10(-8) cm/s) at the south part of the site increases to 10(-5) cm/s at the natural soil of the North side. Extensively faulted and fissured volcanic sandstone levels at the site give potential to waste leachate to reach deep levels. The soil composition, hydraulic conductivity, topographic conditions, and other location criteria in the current solid waste disposal site showed that the current disposal site is not suitable for this purpose. (C) 2013 Elsevier B.V. All rights reserved.
AtıfWoS5OpenAlex6İncele - MakaleAçık Erişim2013Scopus SJRQ2Characterization and pollution potential assessment of Tunceli, Turkey municipal solid waste open dumping site leachates
Demirbilek, Deniz; Önal, Ayten Oztufekci; Demir, Veysel; Uslu, Gulsad; Arslanoglu-Isik, Hilal
Environmental monitoring of leachate quality from an open municipal solid waste dumping site in Tunceli, Turkey was studied in this research. The most commonly examined pollution parameters were determined on a seasonal basis. The annual average 5-day biological oxygen demand (BOD5) and chemical oxygen demand (COD) values of station points were measured as 70 and 425 mg/L, respectively, and also the average BOD5/COD ratio (a measure of biodegradability) was calculated as 0.20. The low ratio of biodegradability and slightly alkaline pH values in the leachate samples indicated that the site was characterized by methanogenic conditions. The mean ammonium-nitrogen (NH4 (+)-N) and corresponding phosphate (orthophosphate) values were assayed as 70 and 11 mg/L, respectively. The average solids content in the leachates was measured as 4,681 mg/L (total solids) and 144 mg/L (suspended solids). Very low concentrations of iron, manganese, copper, and zinc in the leachate samples were found and the concentration of cadmium was measured below detection limits. Excessive amount of nutrients and high organic and inorganic pollutant content in the leachates pose serious pollution potential to the environment. Since no drainage system or bio treatment exists in this open dumping site, high permeability of natural soil at the site and in the surrounding area and very fractured and crackled rocks under natural soil are indicators of high groundwater pollution potential in this site.
AtıfWoS23OpenAlex21İncele - MakaleAçık Erişim2013Scopus SJRQ3Effect of Fly Ash and Silica Fume on compressive strength, sorptivity and carbonation of SCC
Turk, Kazim; Karatas, Mehmet; Gonen, Tahir
In this paper, ASTM C 618 Class F Fly Ash (FA) at 25%, 30%, 35% and 40% and Silica Fume (SF) at 5%, 10%, 15% and 20% replacement of Portland Cement (PC) CEM I 42.5 in SCC was used to evaluate the effect of types and quantity of powder additions on compressive strength and permeations properties of SCC. To this end, eight types of SCC were designed, in comparison with Vibrated Traditional Concrete (VTC). The results indicated that SCC specimens with SF15 had the highest compressive strength with 73.87 MPa for 130 days. The sorptivity values of SCC specimens with FA and SF were lower than those of VTC specimens regardless of type and quantity of powder additions. On the other hand, the carbonation resistance of VTC was higher than that of SCC specimens containing both SF and FA for all accelerated carbonation periods. Consequently, it can be said that type and quantity of powder additions had an important effect on the correlation among the compressive strength and permeation properties of SCC.
AtıfWoS69OpenAlex85İncele - MakaleAçık Erişim2013Scopus SJRQ4Column Studies on Effect of Phosphate Immobilization on Removal of Metals from Stormwater Runoff in Bioretention Cell
Demir, V.; Bin-Shafique, S.
Batch studies indicated that low cost native materials such as loam soil, juniper mulch, hardwood mulch, pine mulch and sawdust performed efficiently as media in bioretention cell for removal of copper and lead from stormwater runoff. Juniper mulch performed best in batch studies was used in column studies. Column studies suggested that the presence of phosphate has a pronounced effect on metal immobilization. This is due to the formation of metal phosphates that have extremely low solubility. The remaining metals were adsorbed on bioretention media of the bioretention cell. Breakthrough adsorption and desorption curves for lead and copper were measured in presence and absence of phosphate immobilization. Copper reached a breakthrough curve in around 20 days and lead in 30 days. Column studies showed that in all samples addition of phosphate also decreased the leaching of lead and copper back to aqueous solution consistent with lead and copper immobilization.
AtıfWoS3OpenAlex3İncele - BildiriYalnız künye2012Scopus SJRQ2The investigation on physico-chemical parameters of the textile effluents after treatment by white rot fungus Pleurotus djamor
Yildirim, Numan; Tanyol, Mehtap; Dere, Turgay; Cumurcu, Aysenur; Yildiz, Abdunnasir
AtıfWoS3OpenAlex4İncele - MakaleYalnız künye2010Scopus SJRQ3Bioconversion Efficiencies of Lignocellulosic Soy Stalk by Pleurotus eryngii Strains
Yildirim, Numan; Yildiz, Abdunnasir
The bioconversion of soy stalk (SS) lignocellulose by three different starins of Pleurotus eryngii from various origins by solid state fermentation was studied during 40 days. The effect of rice bran ratio, 5% or 10% (w/w), on lignin degradation and laccase activity were measured througout the fermentations while, total crude protein and C/N ratio of the remaining substrate were determined at the end of the fermentations. The degradation of lignocellulose was found by the determination of acid soluble lignin (Klason lignin) content. All the strains degraded lignin with different extents. The amount of lignin degradation was decreased by the addition of the higher quantities of rice bran (SS+10% RB). The highest lignin degradation was obtained as 24.43% by P eryngii var. ferulae (E) and the highest protein level was found to be %13.32 by P eryngii (H). We determined that the laccase activity was generally decreased by the addition of the higher quantities of rice bran (10%). Maximum laccase activity (204.39 U/L) was obtained by P. eryngii (E) on SS + 5% RB at the end of the fermentation. This study showed that, after fungal treatment soy stalk can be used as a feed for ruminants with its higher feeding value.
AtıfWoS2OpenAlex1İncele
