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Tokat, Turkey

Gaziosmanpaşa University is a public university established in 1992 and primarily located in Tokat, Turkey. The university takes its name from the famous Turkish commander Gazi Osman Nuri Pasha, who was born in Tokat. Wikipedia.

Cumurcu T.,Gaziosmanpasa University
Ophthalmic research | Year: 2010

PURPOSE: The objective of this study was to investigate the antioxidant/oxidant status of serum in patients with pseudoexfoliation syndrome (PEX). METHODS: Forty-seven patients with PEX and 32 healthy controls were included in the study. Serum total antioxidant capacity (TAC) and total oxidant status (TOS) levels were determined by using a novel automated method. RESULTS: A significant increase in serum TOS (p < 0.001) and a significant decrease in serum TAC (p < 0.0001) were observed in PEX patients compared to control subjects. CONCLUSION: TAC decreases while the oxidative stress increases in PEX. Copyright 2009 S. Karger AG, Basel. Source

Mamedov B.A.,Gaziosmanpasa University
International Journal of Quantum Chemistry | Year: 2014

This article, written on behalf of Guseinov's friends and colleagues in honor of his 80th birthday, presents a brief biography and an overview of the major themes of his scientific researches. This is an opportunity to summarize Guseinov's main contributions to the quantum theory of atoms, molecules, and nuclei. Some aspects of Guseinov's career and research are highlighted here. © 2013 Wiley Periodicals, Inc. Born 80 years ago in Azerbaijan, physicist Israfil I. Guseinov contributed to the development of quantum chemistry with seminal research on subjects as broad as the Lorentz self-frictional field, Laguerre polynomials, exponential type orbitals, multicenter integrals, and nonrelativistic and relativistic quantum theories. Copyright © 2013 Wiley Periodicals, Inc. Source

Abstract Three kinds of kaolin-based composite phase change materials (Kb-CPCMs) including capric acid (CA), PEG600, and heptadecane (HD) as organic PCMs were fabricated using vacuum impregnation method for latent heat storage (LHS) application in buildings. The surface morphology, compatibility, maximum ratio for impregnated PCM, LHS properties, thermal endurance, thermal conductivity and its effect on the melting times of prepared Kb-CPCMs were investigated by using microscopy, spectroscopy, calorimetry and thermal methods. The seepage test indicated that CA, PEG600 and HD were impregnated maximally into the kaolin as 17.5, 21 and 16.5 wt%, respectively. The fabricated three composites, K/CA, K/PEG600, and K/HD, have a phase change temperature of 30.71, 5.16 and 22.08 C and a latent heat of 27.23, 32.80 and 34.63 J/g, respectively. The thermal cycling test exposed that the thermal reliability of the Kb-CPCMs slightly changed after repeated 1000 heating-cooling cycling. The heat storage rates of the Kb-CPCMs were increased considerably by adding expanded graphite (EG) in mass faction of 5%. All the prepared Kb-CPCMs have good thermal energy storage (TES) function for heating, ventilating and air conditioning (HVAC) in building envelopes because of their suitable LHS properties, high reusability performance and enhanced thermal conductivity. © 2015 Elsevier B.V. All rights reserved. Source

Sari A.,Gaziosmanpasa University
Energy Conversion and Management | Year: 2012

In this study, four kinds of mannitol-fatty acid esters were synthesized as novel organic phase change materials (PCMs) for thermal energy storage applications. The structural characterization of synthesized mannitol hexastearate (MHS), mannitol hexapalmitate (MHP), mannitol hexamyristate (MHM) and mannitol hexalaurate (MHL) were carried out using Fourier Transform Infrared (FT-IR), Proton Nuclear Magnetic Resonance (1H NMR), and 13C NMR spectroscopy methods. Thermal energy storage properties and thermal reliability of the synthesized PCMs were determined using differential scanning calorimetry (DSC) method at a heating rate of 1 °C/min. DSC results showed that the melting temperatures of the PCMs were in the temperature range of 42-65 °C and their latent heat values spanned between 145 and 202 J/g. The latent heats of these PCMs are low compared to mannitol but they fall into the same range as fatty acids. The synthesized PCMs have much lower phase change temperatures and supercooling degree (about 1-8 °C) and compared to the mannitol. They have also better odor, noncorrosivity and thermal durability properties as compared to the fatty acids. Thermal cycling test consisted of repeated 1000 melting/solidification cycles also revealed that the synthesized PCMs have good thermal reliability. In addition, thermal conductivity of the PCMs was increased significantly by addition of expanded graphite (EG) at 10 wt%. Based on all results it can be concluded that the synthesized PCMs, MHS, MHP, MHM and MHL esters can be considered as promising solid-liquid PCMs for solar heating applications. © 2012 Elsevier Ltd. All rights reserved. Source

In this study, a new method was presented for the detection of a static eccentricity fault in a closed loop operating induction motor driven by inverter. Contrary to the motors supplied by the line, if the speed and load, and therefore the amplitude and frequency, of the current constantly change then this also causes a continuous change in the location of fault harmonics in the frequency spectrum. Angular Domain Order Tracking analysis (AD-OT) is one of the most frequently used fault diagnosis methods in the monitoring of rotating machines and the analysis of dynamic vibration signals. In the presented experimental study, motor phase current and rotor speed were monitored at various speeds and load levels with a healthy and static eccentricity fault in the closed loop driven induction motor with vector control. The AD-OT method was applied to the motor current and the results were compared with the traditional FFT and Fourier Transform based Order Tracking (FT-OT) methods. The experimental results demonstrate that AD-OT method is more efficient than the FFT and FT-OT methods for fault diagnosis, especially while the motor is operating run-up and run-down. Also the AD-OT does not incur any additional cost for the user because in inverter driven systems, current and speed sensor coexist in the system. The main innovative parts of this study are that AD-OT method was implemented on the motor current signal for the first time. © 2012 Elsevier Ltd. Source

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