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Erzurum, Turkey

Balci M.,Bayburt University | Nalbant M.O.,Bayburt University | Kara E.,Bayburt University | Gundogdu O,AtaturkUniversity
International Journal of Automotive and Mechanical Engineering | Year: 2014

This study presents a free vibration analysis of a laminated composite beam, based on the Euler-Bernoulli beam theory. A numerical model of the laminated composite beam was obtained for various boundary conditions based on different length-to-thickness ratios for a number of layers, using the finite element method. A planar beam bending element with two nodes, each having two degrees of freedom, was chosen according to Euler-Bernoulli beam theory. The natural frequencies of the laminated composite beam were obtained for each case, and presented in such a way as to display the effect of these changes on the natural frequencies. Eight natural frequencies of clamped-free, clamped-clamped (CC) and simple-simple (SS) composite beams were first obtained for different length-to-thickness ratios (Lx /h), numbers of layers, layer angles and for their different positions. It can be seen that natural frequencies decrease for all modes with increasing length-to-thickness ratio in all cases. © Universiti Malaysia Pahang.

Ozdemir M.E.,AtaturkUniversity | Kavurmaci H.,Yuzuncu Yil University | Avci M.,Adiyaman University
Tamkang Journal of Mathematics | Year: 2014

In this paper, we obtain Ostrowski type inequalities for convex functions.

Medhat M.E.,Nuclear Research Center - Negev | Medhat M.E.,CAS Institute of High Energy Physics | Shan W.,Aerospace Space Center Hospital | Kurudirek M.,AtaturkUniversity
X-Ray Spectrometry | Year: 2015

The objective of the proposed work was to measure concentration of six essential elements, Ca, Cu, Fe, Mn, Sr, and Zn directly in whole blood. The adopted method is based on the theory of attenuation of low energy photons through the whole blood sample. Photons are completely absorbed at energy region approximately (25-100keV), of K-absorption edge for especially low-Z elements and at L-absorption edge especially for high-Z elements. Children, adults, and old people from whom the blood samples are taken are considered as subjects in this study. The aim of this work is not to investigate any disease or specific elemental changes. Blood samples were irradiated by 22.0, 31.0, and 59.5keV photons emitted by 108Cd (1.78GBq), 133Ba (2.92GBq), and 241Am (2.78GBq) radioactive point source. A high resolution high pure germanium spectrometer has been used to detect low energy photons with low counts peaks. When compared to the existing data in literature, it has been found that the results obtained in this study agree well with those reported. There are many advantages of this technique over other methods such as being practical, inexpensive, non-destructive, and can also do analysis fast. © 2015 John Wiley & Sons, Ltd.

Kotan R.,AtaturkUniversity | Okutucu A.,Eastern Anatolia Forestry Research Institute | Ala Gormez A.,AtaturkUniversity | Karagoz K.,AtaturkUniversity | And 4 more authors.
Journal of Phytopathology | Year: 2013

This study was carried out to identify pathogenic bacteria and fungi on mistletoe (Viscum album L.) and investigate their potential use in biological control of this parasitic plant. For this purpose, a total of 48 fungal isolate and 193 bacterial strains were isolated from contaminated V. album during the summers 2005-2006. The isolated bacterial strains and fungal isolates were identified by using the Sherlock Microbial Identification System (MIS; Microbial ID, Newark) and microscopic methods, respectively. The bacterial strains that induced hypersensitive reaction (HR) on tobacco (Nicotiana tabacum L.) and fungal isolates were tested for pathogenicity on young shoots of mistletoe by using injection methods. The pathogenic bacterial strains and fungal isolates were also tested for their activity against mistletoe using spray methods. Five bacterial strains (two Burkholderia cepacia, one each of Bacillus megaterium, Bacillus pumilus and Pandoraea pulminicola) were HR and pathogenicity positive when injected but none of them when sprayed on mistletoe. When fungi were injected, 32 isolates were pathogenic but only thirteen when sprayed on mistletoe. Alternaria alternata VAŞ-202, VAŞ-205, VAŞ-217 and Acremonium kiliense VA-11 fungal isolates were the most effective ones and caused strong disease symptoms on mistletoe. The present study is the first report on the efficiency of potential biocontrol agents against mistletoe in Turkey. © 2012 Blackwell Verlag GmbH.

Nadaroglu H.,AtaturkUniversity | Kalkan E.,BayburtUniversity | Celebi N.,AtaturkUniversity | Tasgin E.,Ataturk University
Clay Minerals | Year: 2015

In this study, a clinoptilolite modified with apolaccase was used to adsorb Reactive Black 5 (RB5) dye from aqueous solution using the batch procedure. The influences of pH, contact time, temperature and absorbent dosage on the adsorption were investigated. The optimum adsorption was obtained at pH = 6, contact time = 60 min, temperature = 25°C and adsorbent dosages of 1.62 and 1.59 mg/50 mL per gram of clinoptilolite and of apolaccase-modified clinoptilolite (LMC), respectively). The adsorption experimental data fitted both the Langmuir and Freundlich isotherm models well. In addition, pseudo-first-order and pseudo-second-order kinetics were used to study the kinetics of RB5 dye adsorption onto natural clinoptilolite and LMC. Adsorption appears to follow pseudo-second-order kinetics with a high correlation coefficient. Thermodynamic parameters such as changes in the free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) of adsorption were calculated. The thermodynamic parameters indicate that the adsorption of RB5 dye onto LMC was less spontaneous, feasible and endothermic. The LMC can be used as an alternative low-cost adsorbent for the dye removal from aqueous solutions. © 2015 Mineralogical Society 2015.

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