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Biostimulation of n-alkane degradation in diesel fuel-spiked soils

Kahraman, Bekir Fatih | Altın, Ahmet | Altın, Süreyya | Demirel-Bayık, Gülçin

Article | 2017 | Soil and Sediment Contamination26 ( 5 ) , pp.486 - 500

Nutrient enhancement of bioremediation with nitrogen, namely biostimulation, increases process performance. Selection of a proper nitrogen source is critical for bioremediation applications. In this study, the effects of different nitrogen sources on biodegradation of C10–C25 n-alkane compounds in diesel fuel-spiked soil were revealed, and the most appropriate nitrogen source for biodegradation of semi- and non-volatile n-alkanes was investigated. Bioremediation of diesel fuel contaminated soil was monitored in lab-scale reactors for 15 days. Ammonium sulfate, potassium nitrate and urea were used as nitrogen sources. Carbon dioxide . . .and oxygen levels in the reactors were recorded to monitor microbiological activity. Contaminant removal process was investigated by pH, heterotrophic plate count, total petroleum hydrocarbons (TPH) and C10–C25 n-alkane analyses. First-order kinetic constants were calculated via respirometric and contaminant concentration data. According to total C10–C25 n-alkane removal levels and degradation rate constants, ammonium sulfate addition resulted in the most efficient contaminant removal followed by potassium nitrate and urea. Simultaneous degradation of individual n-alkanes was observed for all of the nitrogen sources. Urea addition changed the distribution of individual n-alkane concentrations relative to the pre-experimental concentrations. Nitrogen source type had no differential effect on degradation rates of semi- (C10–C16) and non-volatile (C17–C25) fractions. © 2017 Taylor & Francis Group, LLC Daha fazlası Daha az

The Evaluation of Kurtbogazi Dam (Ankara, Turkey) from Hydro-Geochemical and Environmental Aspects

Altın, Ahmet | Bakır, Fatma | Özölçer, İsmail Hakkı

Article | 2010 | WATER RESOURCES MANAGEMENT24 ( 4 ) , pp.747 - 759

KurtbogazA +/- Dam is one of the most significant sources of drinking water sources for Ankara City. In this study, hydro-geochemical properties and pollution sources of surface waters feeding into the dam are determined. In addition, important environmental problems such as squatter's houses and wastewater discharges within protection zones of watershed of the dam are defined and appropriate precautions are discussed. The long-term trend (1998-2007) in water quality results of the dam and the surface waters in the KurtbogazA +/- watershed were studied, utilizing data provided by General Directorate of State Water Works (DSI). The r . . .esults indicate that waters in the watershed can be classified as waters with calcium-bicarbonate. Due to the drought conditions experienced in recent years, the concentrations of the organic materials and nitrogen and phosphorus compounds in the surface waters have increased dramatically since 2005. It is thought that wastewaters discharged by the settlements within the watershed (especially Pazar Township) are responsible for these increases. Preventing wastewater discharges from the squatter's houses and agricultural activities on the absolute and the proximate zones of the watershed and the constructing of a sewerage and treatment plant are the first challenges for the protection of the watersheds Daha fazlası Daha az

An alternative type of photoelectro-Fenton process for the treatment of landfill leachate

Altın, Ahmet

Article | 2008 | Separation and Purification Technology61 ( 3 ) , pp.391 - 397

An alternative type of photoelectro-Fenton (PEF) process has been proposed to remove COD, color and phosphate from the landfill leachates. The process was improved by combining the different type of electro-Fenton (EF) process with UV irradiation. The efficiency of the process and settling characteristics of waste sludge produced from the process were investigated by changing some operating parameters such as initial pH, H2O2 and current. In addition, the proposed process was compared with other treatment processes such as electro-coagulation (EC), electro-Fenton and UV/H2O2 in terms of treatment efficiency. The high removal efficie . . .ncies were observed at the initial pH 3, initial H2O2 concentration, 3000 mg L-1; current, 2.5 A; and treatment time, 20 min. Removal of COD, color and phosphate under the reported conditions were 94%, 97%, 96%, respectively. The obtained results from the comparative experiments revealed that the proposed PEF process is more effective than the other treatment processes for the landfill leachate. © 2007 Elsevier B.V. All rights reserved Daha fazlası Daha az

Industrial noise and its effects on humans

Atmaca, Eyüp | Peker, İ. | Altın, Ahmet

Article | 2005 | Polish Journal of Environmental Studies14 ( 6 ) , pp.721 - 726

The problem of noise in the industries around Sivas has been examined in this study; and noise measurement and survey studies have been carried out at concrete traverse, cement, iron and steel and textile factories located in this region. A questionnaire was completed by 256 workers during this study in order to determine the physical, physiological, and psycho-social impacts of the noise on humans and to specify what kind of measurements have been taken both by the employers and workers for protection from the effects of noise. It has been specified, during the surveys, that the noise levels detected in all the industries are much . . .above the 80 dBA that is specified in the regulations: 73.83% of the workers in these industries are disturbed from the noise in their workplaces, 60.96% of them have complaints about their nervous situations, 30.96% of these workers are suffering hearing problems although they had not had any periodical hearing tests and they are not using ear protection equipment Daha fazlası Daha az

Comparison of electrodialysis and reverse electrodialysis processes in the removal of Cu(II) from dilute solutions

Altın, Süreyya | Öztekin, Elif | Altın, Ahmet

Article | 2017 | Korean Journal of Chemical Engineering34 ( 8 ) , pp.2218 - 2224

Electrodialysis (ED) and electrodialysis reversal (EDR) processes have been often used for separation of ions in dilute solutions. In this study, the performance of ED and EDR processes has been examined in the removal of copper from the dilute solutions. First, applied voltage, initial concentration, flow rate, type of electrolyte and the effect of concentration were determined for both processes. Then, separation efficiency, current efficiency, energy requirement and material flux of the processes were calculated, and the performances of the processes were compared. The separation efficiency and energy consumption of EDR process w . . .ere higher compared to ED process under equal operating conditions. Also, the current efficiency (39.58%) of EDR process was lower than the current efficiency (67.46%) of ED process. It can be said that the ED process is more suitable in terms of energy consumption for separation in the low flow rate and concentration. © 2017, Korean Institute of Chemical Engineers, Seoul, Korea Daha fazlası Daha az

Removal of Cadmium ions from aqueous solutions by microorganisms of activated sludge

Altın, Süreyya | Altın, Ahmet | Kahraman, Bekir Fatih | Alemdar, Sonay | Alaydın, Elif

Article | 2015 | Fresenius Environmental Bulletin24 ( 1B ) , pp.302 - 310

In this study, the utilization of dried activated sludge for removal of Cd2+ from aqueous solution in a batch system was investigated. Initial pH, biosorbent dosage, contact time, and initial metal concentration parameters were selected to determine optimal process conditions. The bi-osorption mechanism was examined by SEM, FTIR and EDX results. The optimum conditions for Cd2+ biosorption were found to be 6.0, 120 min., 1.2 g. L-1 and 80 mg. L-1, respectively for initial pH, contact time, biosorbent dosage and initial Cd2+ concentration. Langmuir and Freundlich isotherms were used to model the biosorption equilibrium data, and it wa . . .s determined that the system followed the Langmuir isotherm, and the sorption capacity of the biosorbent was found to be 15.43 mg.g-1. Biosorption followed a pseudo-second-order rate model. Two main mechanisms of Cd2+ biosorption onto the dried activated sludge were adsorption to the C-H bonds and ion exchange with Na+, K+ and Ca2+ ions Daha fazlası Daha az

Conversion of an industrial waste to an oil sorbent by coupling with functional silanes

Demirel Bayık, Gülçin | Altın, Ahmet

Article | 2018 | Journal of Cleaner Production196 , pp.1052 - 1064

The aim of the present study is to produce an oil sorbent from paper industry waste by reducing the water sorption capacity with silane coating. Waste material was pretreated and then coupled with two different kinds of alkoxysilane, by solution immersion process. Coated material was characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and contact angle measurements. Oil and water selectivity from water surface were evaluated for three different oil types. Production cost of the sorbent was determined and compared with other commercial products. Effect of silane coupling on water sorpti . . .on percentage was more apparent for thinner oil film thickness which was 0.127 cm. The water percentage for uncoated sorbent at this film thickness was 38.24% for diesel-oil mixture. For surface coated material, water sorption percentages were 9.27% for (3-Aminopropyl)triethoxysilane (APS) and 10% for 3-(Trimethoxysilyl) propyl methacrylate (MPS). The results show that industrial waste can be converted into an oil sorbing material by silane coupling. After coating, the material can be a good alternative for the removal of spilled oil. © 201 Daha fazlası Daha az

Environmental awareness level of secondary school students: A case study in Balikesir (Turkiye)

Altın, Ahmet | Tecer, Selcen | Tecer, Lokman | Altın, Süreyya | Kahraman, Bekir Fatih


In this study, secondary school students' awareness of environmental issues and problems and the level of their active participation in environmental activities have been identified, and the effects of some factors as family school and media on their environmental awareness and active participation have been investigated. The study was carried out in Balikesir city centre by conducting a survey on senior students consisting of 6 classes from three secondary schools which have different demographic and socio-economic levels. The results of the study showed a high level of environmental awareness among participant students. However, i . . .t is understood that environmental disclosures made in schools are insufficient and the participation level of students to environmental activities is low. Students rather gain experiences in the field of environment from mass media (i.e. audio, printed and visual media). It is revealed that female students have a higher level of environmental awareness and active participation level. In addition, when family income and family education level increases, environmental awareness and active participation level of students also increases. (C) 2014 Published by Elsevier Ltd Daha fazlası Daha az

Treatment of kraft pulp and paper mill wastewater by electro-fenton/electro-coagulation process

Altın, Ahmet | Altın, Süreyya | Yıldırım, Ömür

Article | 2017 | Journal of Environmental Protection and Ecology18 ( 2 ) , pp.652 - 661

The present study aims to examine the electro-Fenton/electro-coagulation (EF/EC) process for the treatment of wastewater generated from Kraft pulp and paper mills. As a result of the experimental studies, the optimum operating parameters of the EF/EC process have been identified as follows: current = 1.0 A, initial H2O2 concentration = 1000 mg/l and initial pH 2.5. It has been established that, under these conditions, the COD could be removed at 91.7%. It has been understood that the sludge produced from the EF/EC reactor possesses fairly good sedimentation characteristics and is significantly affected by the operating parameters. I . . .t has been established that the best sedimentation characteristics can be achieved when the current is ? 1.0 A, the initial pH value is between 2.3 and 3.2, and the initial H2O2 concentration is between 400 and 1800 mg/l Daha fazlası Daha az

Separation of Cd(II) from aqueous solutions by a new consecutive process consisting of supported liquid membrane and electrodialysis

Altın, Süreyya | Altın, Ahmet

Article | 2019 | Journal of Electrochemical Science and Technology10 ( 1 ) , pp.14 - 21

Supported liquid membrane process usually is used for recovering or enrichment of valuable metals in the industrial wastewater. But, even if the metals in the wastewater was separated with high chemical selectivity, it cannot be enough concentrated since separation performance of supported liquid membrane (SLM) process is limited by concentration gradient between feed solution and stripping solution. If metal concentration in the stripping solution to be enough low, transport of metal through membrane can be accomplishment constantly. Therefore, Electrodialysis (ED) has been placed after SLM process and the stripping solution of SLM . . . was used as the feed solution for the ED process. Transport of ions in the solutions is successfully performed by ED process. Thus, the metal concentration in the stripping solution does not rise as to stop ion transport. Besides, valuable metals easily are concentrated by ED process for re-use. In this study, effects of operation parameters like initial Cd(II) concentration, HCl concentration in the feed solution of SLM and applied voltage are investigated on separation efficiency, flux and permeability of the both processes. As the feed solution concentration increased, all performance values has increased. When initial concentration of 100 mg/L is used, separation performances (SP) are 55% and 70%, for SLM and consecutive process, respectively. The best HCl concentration in the feed solution of SLM has determined as 2 M, in this conditions SP are 64% and 72%, for SLM and consecutive process, respectively. With increased of applied voltage on ED process, SP of the consecutive process has been raised from 72% to 83%. According to the obtained experimental data, consecutive process has better separation performance than SLM. When the separation performances of both processes were compared for the same operating conditions, it was determined higher the separation efficiency, permeability and flux values of the consecutive process, 8%, 9% and %10.6, respectively. Consequently, the use of the consecutive process increases the performance efficiency of both processes. The consecutive process studied has quite a good chemical separation efficiency, and enrichment capability. Moreover, this process requires few water and energy. © 2019, Korean Electrochemical Society. All rights reserved Daha fazlası Daha az

Environmental knowledge of primary school students: Zonguldak (Turkey) example

Alaydın, Elif | Demirel, Gülçin | Altın, Süreyya | Altın, Ahmet


The number of environmentally conscious individuals in society can be raised by increasing environmental education quality in primary schools. Starting studies about environment in the childhood years is very important. In this study, the knowledge and skill levels of primary school students in Zonguldak about waste recycling was determined, and the participation levels of theirs into recycling activities was measured. For this aim, the third and fourth grade primary school students were identified as a target group of the study, and a questionnaire assessing the impact of the parents' socio-economic structures and education status . . .on environmental awareness of theirs was prepared. The results were evaluated to determine the strengths and weaknesses of environmental education of the students, statistically. The questionnaire was conducted in three elementary schools having different social and economic levels. Questions in the first, second and last parts of the questionnaire relate with the demographic characteristics of students families, the environmental awareness of the students, and the participation of students into recycling activities, respectively. The survey reviews were carried out with a statistical program and differences between the schools were determined by using one way ANOVA test. (C) 2014 The Authors. Published by Elsevier Ltd Daha fazlası Daha az

Facilitated transport of Cd(II) through a supported liquid membrane with Aliquat 336 as a carrier

Altın, Süreyya | Alemdar, Sonay | Altın, Ahmet | Yıldırım, Yılmaz

Article | 2011 | Separation Science and Technology46 ( 5 ) , pp.754 - 764

Selective removal of cadmium from wastewaters is very important, because cadmium is toxic for the environment and for human health. This work is a comprehensive study on the selective removal of Cd(II) from aqueous solutions by using a co-current flow flat sheet supported liquid membrane system. 4.4 × 10-4M Cd(II) concentration was used as a feed solution in the experiments. Toluene containing Aliquat 336 was used as the membrane liquid in the membrane system. Parameters such as the properties of feed and stripping solutions, carrier concentration, and flow rate, which have roles in transport of Cd(II) ions, were optimized. The effi . . .ciency of the system is expressed in terms of permeability and flux values, and transport efficiency. The optimum process conditions for the Cd(II) transport are experimentally found as follows: The feed solution as 2 M HCl, the carrier concentration as 0.1 M Aliquat 336, the stripping solution as 0.06 M EDTA, and the flow rates for the feed and stripping solutions as 50 mL/min and 80 mL/min, respectively. Under these conditions, the Cd(II) transport efficiency is found to be 82%. © Taylor & Francis Group, LLC Daha fazlası Daha az

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