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Szulczyk K.R.,Suleyman Demirel University of Kazakhstan | McCarl B.A.,Texas A&M University
Renewable and Sustainable Energy Reviews | Year: 2010

This research examines in detail the technology and economics of substituting biodiesel for diesel #2. This endeavor examines three areas. First, the benefits of biodiesel are examined, and the technical problems of large-scale implementation. Second, the biodiesel production possibilities are examined for soybean oil, corn oil, tallow, and yellow grease, which are the largest sources of feedstocks for the United States. Examining in detail the production possibilities allows to identity the extent of technological change, production costs, byproducts, and greenhouse gas (GHG) emissions. Finally, a U.S. agricultural model, FASOMGHG was used to predict market penetration of biodiesel, given technological progress, variety of technologies and feedstocks, market interactions, energy prices, and carbon dioxide equivalent prices. FASOMGHG has several interesting results. First, diesel fuel prices have an expansionary impact on the biodiesel industry. The higher the diesel fuel prices, the more biodiesel is produced. However, given the most favorable circumstances, the maximum biodiesel market penetration is 9% in 2030 with a wholesale diesel price of $4 per gallon. Second, the two dominant sources of biodiesel are from corn and soybeans. Sources like tallow and yellow grease are more limited, because they are byproducts of other industries. Third, GHG prices have an expansionary impact on the biodiesel prices, because biodiesel is quite GHG efficient. Finally, U.S. government subsidies on biofuels have an expansionary impact on biodiesel production, and increase market penetration at least an additional 3%. © 2010 Elsevier Ltd.

Kharin S.N.,Kazakh-British Technical University | Sarsengeldin M.,Suleyman Demirel University of Kazakhstan
Key Engineering Materials | Year: 2012

Investigation of transition phenomena accompanying the evolution of metallic phase of electric arc into gaseous phase is very important for the further progress in such fields as plasma technologies, electrical apparatus, plasmatrons and other technical applications. Some aspects of this transition are considered in presented paper on the base of mathematical model described dynamics of phenomena in the arc column, near-electrode zones, anode and cathode solids. Cathode and anode phenomena such as ion bombardment, thermionic emission, inverse electron flux, evaporation, radiation, heat conduction etc. are considered in dependence on time, current, opening velocity, parameters of the gas and contact materials. The conditions of the arc transition from one phase to another are formulated in terms of above characteristics and increasing of gas ionization level. Special experiments with two contacts materials, AgCdO and AgSnO 2 have been carried to verify the mathematical model. The results of calculation and experimental data enables us to conclude that in metallic arc phase (short arc length), which is characterized by material transfer from the anode to the cathode, the erosion of AgSnO 2 contacts is considerably small than erosion of AgCdO contacts both for resistive and inductive circuits, while in gaseous arc phase (long arc length) with opposite material transfer the rate of erosion depends on the inductance. If the inductance L = 0, then AgSnO 2 contacts have smaller erosion in comparison with AgCdO contacts, however for inductive circuits situation is quite different, thus use of AgCdO contacts in the case of long arcs burning in gaseous phase is more preferable. It was found also that the addition of niobium diselenide NbSe 2 (1%) and tantalum Ta (5%) into silver contact material which are sublimating into arc plasma enables to change ionization potential, that leads to decreasing of the arc temperature, arc duration and contact erosion. © (2012) Trans Tech Publications.

Koseoglu Y.,Fatih University | Koseoglu Y.,Suleyman Demirel University of Kazakhstan
Ceramics International | Year: 2014

A simple microwave-assisted combustion route was used first time for the preparation of nanocrystalline ZnO nanoplatelets using dissolution of zinc nitrate as the oxidant and glycin as fuel. The structure, morphology and composition of the as-prepared samples were investigated by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectra (EDX). The XRD results confirmed the formation of single phase hexagonal wurtzite structure of ZnO and SEM pictures indicated that the sample includes the nanostructured nanoplatelets with the porous surface of the products. The optical properties were determined by a UV-vis spectrophotometer and the results showed that the as prepared ZnO nanoplatelets have larger band gap of 3.06 eV. Vibrating sample magnetometer (VSM) was used for the magnetic property investigations and ZnO nanoplatelets indicated room temperature ferromagnetism which is intrinsic in nature and attributed to oxygen and/or Zn deficiencies as found in EDX results. © 2013 Elsevier Ltd and Techna Group S.r.l.

Sencan A.,Suleyman Demirel University of Kazakhstan
Environmental Earth Sciences | Year: 2011

Conventional methods using for removing heavy metals from waste water such as ion change, sedimentation, electrochemical and membrane processes, active carbon adsorption, evaporization and solvent extraction methods have high preliminary investments and operation costs. Furthermore, after the physicochemical refinement processes, subsidiary pollutants which are harmful to the environment occurs. Because of these reasons, biosorption processes improvement studies have been speeded up. Biosorption processes are the methods that are used for absorbing heavy metals from waste water by using biological substances. Using proper biomass is a cheaper process than those mentioned above. Moreover, the operation is easier than these processes. Many studies in the literature, it was determined that heavy metals were held on the surface of the dead bacteria, fungi and alga. In this study, it was also aimed to find out the capacity of heavy metal biosorption found in waste water by active sludge biomass which contains a number of bacteria, protozoa, fungi and rotifer kinds. Biosorption studies are carried out with batch technique. In this extent, the solutions which include chrome (VI) are used and optimum conditions on which biomass is successful in biosorpting these metals. The IR spectra's of raw sludge and CR+6 charged biomass were taken for determine the effective functional groups on the adsorption. And for the biosorption process, kinetics and isotherm studies were also conducted. Finally, it was determined that biosorption can be explained with second degree kinetic and isotherm datum is compatible with Freundlich and Langmuir's isotherm modal. © Springer-Verlag Berlin Heidelberg 2011.

Koseolu Y.,Fatih University | Koseolu Y.,Suleyman Demirel University of Kazakhstan
Journal of Magnetism and Magnetic Materials | Year: 2015

Nanoparticles of Co0.1Zn0.9O were successfully synthesized by a simple polyethylene-glycol (PEG)-assisted hydrothermal method. A systematic investigation was done to determine the structural, morphological and magnetic properties of the as synthesized sample and XRD, FE-SEM and EDX measurements were conducted respectively for the structural, morphological and compositional investigation of the product. For the magnetic property investigations VSM was used. Additionally FMR was further used to confirm the room temperature ferromagnetism of the sample. Average particle size of the nanoparticles was estimated using Debye-Scherers equation and found as 23.5 nm. SEM image of the nanoparticles confirms that the size of the nanoparticles vary between 20 nm and 100 nm with small aggregation. Magnetization measurements have shown that the particles have room temperature ferromagnetic behavior with relatively high coercive fields which are decreasing with the temperature as expected. FMR spectrum also confirms the room temperature ferromagnetism of the product without any metallic precipitates. © 2014 Elsevier B.V. All rights reserved.

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