http://hdl.handle.net/11513/19 Mühendislik Fakltesine'ne ait bölümleri içerir. Wed, 08 Apr 2026 22:01:36 GMT 2026-04-08T22:01:36Z http://hdl.handle.net/11513/343 Title: Sorption of alpha and beta hydrophobic endosulfan in a Vertisol from southeast region of Turkey Authors: Atasoy, Ayşe Dilek; Mermut, Ahmet Ruhi; Kumbur, Halil; İnce, Faruk; Arslan, Hüdaverdi; Avcı, Emel Deniz Abstract: Endosulfan has been applied to control numerous insects in a variety of food and non-food crops. Limited information is available on dynamics of this pesticide in the soil. The objective of this research was to determine the adsorption–desorption behavior of the alpha (a) and beta (b) endosulfan in a Vertisol from the southeast region of Turkey, where cotton is the main crop in the large irrigated lowlands. The a and b endosulfan were adsorbed considerably and Freundlich adsorption–desorption isotherms fitted the a and b endosulfan data (R2 > 0.98). Freundlich adsorption coefficients (Kf) for the a endosulfan ranged between 21.63 and 16.33 while for the b endosulfan they were between 14.01 and 17.98 for the Ap and Bw2 horizons. The difference of Kf values of a and b endosulfan for two horizons were explained with the slight difference in the amount of organic matter and clay, but considerable difference in Fe contents of the two horizons. Alpha and b endosulfan Kfd values were 118.03 and 45.81 for the Ap and 48.08 and 68.71 for the Bw2 horizons. Higher adsorption and desorption behavior of the endosulfan isomers for the same horizon was attributed to poor physical bonding between the endosulfan molecule and the surfaces of fundamental soil particles. This fact is thought to increase the effective use of endosulfan in agriculture with a possibility of its movement to the surface and groundwater in the Vertisol studied. Thu, 01 Jan 2009 00:00:00 GMT http://hdl.handle.net/11513/343 2009-01-01T00:00:00Z http://hdl.handle.net/11513/342 Title: Effect of high sulfate concentration on the corrosivity: a case study from groundwater in Harran Plain, Turkey Authors: Atasoy, Ayşe Dilek; Yeşilnacar, Mehmet İrfan Abstract: Corrosion, which tends to increase the concentrations of certain metals in tap water, is one of the most important water quality problems as it can affect public health and public acceptance of water supply and the cost of providing safe water. In this context, this study aimed at investigating the scale formation tendency or corrosivity of groundwater in the semi-arid Harran Plain. The degree of scale formation tendency/corrosivity of water was determined considering pHs, Langelier Index, and Ryznar Index of groundwater samples. Except for well no.4, which is close to a local hot spring, all the wells had corrosive characteristics. The amount of CO2 from the soil zone respiration and high sulfate concentration in the wells are important factors affecting corrosiveness. Results showed that precipitation, excessive irrigation, and change in groundwater level caused seasonal variation in corrosive characteristics. Fri, 01 Jan 2010 00:00:00 GMT http://hdl.handle.net/11513/342 2010-01-01T00:00:00Z http://hdl.handle.net/11513/341 Title: Artificial Neural Network Prediction of the Performance of Upflow and Downflow Fluidized Bed Reactors Treating Acidic Mine Drainage Water Authors: Atasoy, Ayşe Dilek; Babar, B.; Şahinkaya, Erkan Abstract: The performance of fluidized bed reactors treating synthetic acid mine drainage were predicted using an artificial neural network (ANN). The developed model gave satisfactory fits to the experimentally obtained sulfate, COD, alkalinity, and sulfide data; R-values were within 0.92 and 0.98. ANN can be effectively used to predict the performance of these complex systems and, with the proposed model-based applications, it is possible to reduce operational costs and risks. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/11513/341 2013-01-01T00:00:00Z http://hdl.handle.net/11513/340 Title: Adsorption of Fluoride on the Raw and Modified Cement Clay Authors: Atasoy, Ayşe Dilek; Özdemir Şahin, Müge Abstract: Adsorption of fluoride (F) on the raw and modified local cement clay was investigated by batch method. Modified clays were prepared through calcination, using the Na and Mg saturated (C-Na, C-Mg) clay at 500 and 850°C (C-500, C-850) and calcination of Mg incorporated clay at 500°C (C-Mg-500). The equilibration time was attained in 5 h. Adsorption of F increased with increasing adsorbent dose. Decrease of the initial F concentration resulted in an increasing amount of F adsorption. F adsorption isotherms fitted well with both Freundlich and Langmuir models. Low F adsorption was obtained on the raw, incorporated or calcined clays. However maximum F adsorption was found for C-Mg-500, with Kf and Q0 values of 0.27 and 1.69, respectively. This work indicated that the calcination of incorporated clay with Mg increased the F adsorption significantly, due to increased and stabilized positive sites. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/11513/340 2013-01-01T00:00:00Z