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Dursun E.,Marmara University | Ozalp G.Y.,International Center for Hydrogen Energy Technologies | Kilic O.,Marmara University
International Review of Electrical Engineering

The proton exchange membrane fuel cell (PEMFC) which has low operating temperature, high power density and zero emission is the most suitable one for energy applications. In this study, two different PEMFCs membrane electrode assemblies (MEA) are tested in terms of electrical characteristics in different temperatures and humidity. Then these results are compared with improved PEMFCs electrical circuit model. This model is developed in MATLAB/Simulink®. © 2010 Praise Worthy Prize S.r.l. - All rights reserved. Source

Acikgoz B.,International Center for Hydrogen Energy Technologies | Celik C.,Kocaeli University
International Journal of Hydrogen Energy

In this paper, the performance and emission characteristics of a conventional twin-cylinder, four stroke, spark-ignited (SI) engine that is running with methane-hydrogen blends have been investigated experimentally. The engine was modified to realize hydrogen port injection by installing hydrogen feeding line in the intake manifolds. The experimental results have been demonstrated that the brake specific fuel consumption (BSFC) increased with the increase of hydrogen fraction in fuel blends at low speeds. On the other hand, as hydrogen percentage in the mixture increased, BSFC values decreased at high speeds. Furthermore, brake thermal efficiencies were found to decrease with the increase in percentage of hydrogen added. In addition, it has been found that CO 2, NO x and HC emissions decrease with increasing hydrogen. However, CO emissions tended to increase with the addition of hydrogen generally increase. It has been showed that hydrogen is a very good choice as a gasoline engine fuel. The data are also very useful for operational changes needed to optimize the hydrogen fuelled SI engine design. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Yazici M.S.,International Center for Hydrogen Energy Technologies
International Journal of Hydrogen Energy

The International Centre for Hydrogen Energy Technologies (ICHET) has been implementing measures to demonstrate potential benefits of "hydrogen and fuel cell systems" in developing countries. ICHET is a United Nations Industrial Development Organization (UNIDO) project funded by the Turkish Ministry of Energy and Natural Resources. To achieve its mission, ICHET implements pilot demonstration projects, provides applied research and development funding, and organizes workshops, education and training activities. Long term objective of the centre are to show implementation of hydrogen energy technologies with renewable energy systems and encourage local industries to manufacture similar systems for commercial applications. Support has been provided to select industrial partners in Turkey for developing prototypes including a fuel cell forklift, a fuel cell boat, a fuel cell passenger cart, renewable energy systems integrated mobile house, fuel cell based Uninterrupted Power Supply (UPS) installations. As more and more systems are demonstrated, public awareness of applications of hydrogen and fuel cell technologies will increase. ICHET has polymer electrolyte membrane (PEM) fuel cell testing capabilities together with analytical equipment to conduct fuel cell, hydrogen production and storage research. These facilities are being used for educational purposes with hundreds of engineers trained to date. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Gokce E.C.,Ankara University | Kahveci R.,Ministry of Health | Atanur O.M.,International Center for Hydrogen Energy Technologies | Gurer B.,Fatih Sultan Mehmet Education and Research Hospital | And 6 more authors.

Introduction Ganoderma lucidum (G. lucidum) is a mushroom belonging to the polyporaceae family of Basidiomycota and has widely been used as a traditional medicine for thousands of years. G. lucidum has never been studied in traumatic spinal cord injury. The aim of this study is to investigate whether G. lucidum polysaccharides (GLPS) can protect the spinal cord after experimental spinal cord injury. Materials and methods Rats were randomized into five groups of eight animals each: control, sham, trauma, GLPS, and methylprednisolone. In the control group, no surgical intervention was performed. In the sham group, only a laminectomy was performed. In all the other groups, the spinal cord trauma model was created by the occlusion of the spinal cord with an aneurysm clip. In the spinal cord tissue, caspase-3 activity, tumour necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, nitric oxide levels, and superoxide dismutase levels were analysed. Histopathological and ultrastructural evaluations were also performed. Neurological evaluation was performed using the Basso, Beattie, and Bresnahan locomotor scale and the inclined-plane test. Results After traumatic spinal cord injury, increases in caspase-3 activity, tumour necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, and nitric oxide levels were detected. After the administration of GLPS, decreases were observed in tissue caspase-3 activity, tumour necrosis factor-alpha levels, myeloperoxidase activity, malondialdehyde levels, and nitric oxide levels. Furthermore, GLPS treatment showed improved results in histopathological scores, ultrastructural scores, and functional tests. Conclusions Biochemical, histopathological, and ultrastructural analyses and functional tests reveal that GLPS exhibits meaningful neuroprotective effects against spinal cord injury. © 2015 Elsevier Ltd. All rights reserved. Source

Meryemoglu B.,Cukurova University | Hesenov A.,Cukurova University | Irmak S.,Cukurova University | Atanur O.M.,International Center for Hydrogen Energy Technologies | And 2 more authors.
International Journal of Hydrogen Energy

Aqueous-phase reforming (APR) of real biomass was studied for production of hydrogen gas. Wheat straw, an abundant by-product from wheat production was used as representative lignocellulosic biomass. Wheat straw was hydrolyzed in an environmentally benign-sub critical water condition. APR experiments of wheat straw hydrolysates were performed using commercial catalysts which were made of Pt, Pd and Ru doped on carbon, activated carbon and alumina supports for production of hydrogen rich gas mixture. The activity and selectivity of two commercial raney-nickel catalysts were also monitored in terms of hydrogen production. Among the precious metal catalysts tested, activity of the metals for hydrogen production was in the following descending order: Pt > Ru > Pd. Results indicated that alumina support significantly lowered the catalytic performance of the catalysts. Based on whole catalyst material, raney-nickel catalysts were more active than supported precious metal catalysts tested. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved. Source

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