Arama Sonuçları

Listeleniyor 1 - 10 / 32
  • Öğe
    Uluslararası kültürel miras mevzuatı
    (Kültürel Mirasın Dostları Derneği, 2007) Aydın, Mahmut; Öz, Ali Kazım; Güner, Saadet; Aydın, Mahmut; Öz, Ali Kazım; Güner, Saadet; Kapan, Deniz
  • Öğe
    Biodiesel production from inedible animal tallow and an experimental investigation of its use as alternative fuel in a direct injection diesel engine
    (Elsevier, 2009-02-15) Altun, Şehmus; Öner, Cengiz
    In this study, a substitute fuel for diesel engines was produced from inedible animal tallow and its usability was investigated as pure biodiesel and its blends with petroleum diesel fuel in a diesel engine. Tallow methyl ester as biodiesel fuel was prepared by base-catalyzed transesterification of the fat with methanol in the presence of NaOH as catalyst. Fuel properties of methyl ester, diesel fuel and blends of them (5%, 20% and 50% by volume) were determined. Viscosity and density of fatty acid methyl ester have been found to meet ASTM D6751 and EN 14214 specifications. Viscosity and density of tallow methyl esters are found to be very close to that of diesel. The calorific value of biodiesel is found to be slightly lower than that of diesel. An experimental study was carried out in order to investigate of its usability as alternative fuel of tallow methyl ester in a direct injection diesel engine. It was observed that the addition of biodiesel to the diesel fuel decreases the effective efficiency of engine and increases the specific fuel consumption. This is due to the lower heating value of biodiesel compared to diesel fuel. However, the effective engine power was comparable by biodiesel compared with diesel fuel. Emissions of carbon monoxide (CO), oxides of nitrogen (NOx), sulphur dioxide (SO2) and smoke opacity were reduced around 15%, 38.5%, 72.7% and 56.8%, respectively, in case of tallow methyl esters (B100) compared to diesel fuel. Besides, the lowest CO, NOx emissions and the highest exhaust temperature were obtained for B20 among all other fuels. The reductions in exhaust emissions made tallow methyl esters and its blends, especially B20 a suitable alternative fuel for diesel and thus could help in controlling air pollution. Based on this study, animal tallow methyl esters and its blends with petroleum diesel fuel can be used a substitute for diesel in direct injection diesel engines without any engine modification.
  • Öğe
    The comparison of engine performance and exhaust emission characteristics of sesame oil-diesel fuel mixture with diesel fuel in a direct injection diesel engine
    (Elsevier, 2008-01-09) Altun, Şehmus; Bulut, Hüsamettin; Öner, Cengiz
    The use of vegetable oils as a fuel in diesel engines causes some problems due to their high viscosity compared with conventional diesel fuel. Various techniques and methods are used to solve the problems resulting from high viscosity. One of these techniques is fuel blending. In this study, a blend of 50% sesame oil and 50% diesel fuel was used as an alternative fuel in a direct injection diesel engine. Engine performance and exhaust emissions were investigated and compared with the ordinary diesel fuel in a diesel engine. The experimental results show that the engine power and torque of the mixture of sesame oil-diesel fuel are close to the values obtained from diesel fuel and the amounts of exhaust emissions are lower than those of diesel fuel. Hence, it is seen that blend of sesame oil and diesel fuel can be used as an alternative fuel successfully in a diesel engine without any modification and also it is an environmental friendly fuel in terms of emission parameters.
  • Öğe
    Batman ilinin doğal gaz ihtiyacının ve hava kirliliğini azaltmasının matematiksel yöntemlerle modellenmesi
    (Karabük Üniversitesi, 2009) Aydın, Hüseyin; Yaşar, Fevzi; Bezek Güre, Özlem
  • Öğe
    An analysis of biodiesel requirement, production and policies in Turkey
    (e-Journal of New World Sciences Academy, 2008-02-01) Aydın, Hüseyin; Bayındır, Hasan
    The development of alternative fuels from renewable resources, like biomass, has gained considerable attention in recent years. A biodiesel program would give many benefits in terms of generation of employment for poor/rural people, farmers, accelerate of starting many type of industries for developing countries like Turkey. This paper investigates current status of biodiesel in Turkey, advantages and disadvantages of biodiesel in diesel engines, annual diesel fuel consumption, import and export ratings and annual diesel fuel demand. The main focus of this paper is on Turkey’s current fuel status and to clarify Turkey’s biodiesel demand as alternative to fossil diesel fuel. Results show that Turkey is highly in need of alternative energies such as bio-fuels. That’s way it is recommended that Turkey should promote oilseed crops farming to the rise production of biodiesel.
  • Öğe
    Hayvansal iç yağlardan transesterifikasyon reaksiyonu ile biyodizel üretilmesi
    (Doğu Anadolu Bölgesi Araştırma ve Uygulama Merkezi, 2008-07-31) Altun, Şehmus; Öner, Cengiz
    Hayvansal yağlar normal çevre sıcaklığında katı ve çok viskozdurlar. Yüksek viskozitelerinden dolayı dizel motorlarında kullanılmadan önce modifiye edilmeleri gerekmektedir. Hayvansal yağların dizel motorlarında kullanılabilirliliğini iyileştirmek için emülsiyon ve transesterifikasyon etkili iki yöntemdir. Bu çalışmada hayvansal iç yağlardan baz katalizörlü transesterifikasyon ile %99.7 saflıkta metil alkol ve katalizör olarak %98 saflıkta NaOH kullanılarak hayvansal iç yağı metil esteri (biyodizel) üretilmiştir. Hayvansal iç yağı, metil ester şekline dönüştükten sonra viskozitesi önemli ölçüde azalmış ve oda sıcaklığında sıvı fazında bir yakıt elde edilmiştir. Biyodizelin belirlenen yakıt özellikleri ASTM standartlarında olup, viskozitesi ve yoğunluğu dizel yakıtına yakın, ısıl değeri ise %8 daha düşük çıkmıştır.
  • Öğe
    Callus induction and plant regeneration from different explants of actinidia deliciosa
    (Springer Nature, 2008-10-31) Akbaş, Filiz; Işıkalan, Çiğdem; Namlı, Süreyya
    In this study, an efficient procedure was developed for callus induction and regeneration of kiwifruit (Actinidia deliciosa) using different organs of shoots developed under in vitro conditions. Effects of explants source and media (M1, 1.0 mg l-1 BA + 2.0 mg l-1 2,4-D-M 2, 1.0 mg l-1 NAA + 2.0 mg l-1 2,4-D) on initiation of callus were examined in order to obtain callus for organogenesis. The best callus for plant regeneration was obtained from leaf explants on Murashige and Skoog's medium (MS) supplemented with M2. Formation of callus from leaf of kiwifruit (A. deliciosa) was cultured in MS medium containing different concentration of N6-benzylaminopurin (BA; 0.0, 1.0, 2.0, 4.0, 6.0, 8.0 mg l-1) for callus proliferation and plant regeneration. Although the first shoot formation was appeared in medium containing 6.0 and 8.0 mg l-1 BA, the best shoots formation was obtained in medium with 4.0 mg l-1 BA.
  • Öğe
    Radiation dose estimation and mass attenuation coefficients ofcement samples used in Turkey
    (Elsevier, 2009-12-16) Damla, Nevzat; Çevik, Uğur; Kobya, Ali İhsan; Çelik, Ahmet; Çelik, Necati; Grieken, R. Van
    Different cement samples commonly used in building construction in Turkey have been analyzed for natural radioactivity using gamma-ray spectrometry. The mean activity concentrations observed in the cement samples were 52, 40 and 324 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and world average limits. The radiological hazard parameters such as radium equivalent activities (Raeq), gamma index (Iγ) and alpha index (Iα) indices as well as terrestrial absorbed dose and annual effective dose rate were calculated and compared with the international data. The Raeq values of cement are lower than the limit of 370 Bq kg−1, equivalent to a gamma dose of 1.5 mSv y−1. Moreover, the mass attenuation coefficients were determined experimentally and calculated theoretically using XCOM in some cement samples. Also, chemical compositions analyses of the cement samples were investigated.
  • Öğe
    Bir dizel motorunda kanola yağı kullanımında ön-ısıtma işleminin egzoz emisyonlarına etkilerinin deneysel araştırılması
    (e-Journal of New World Sciences Academy, 2009-03-01) Aydın, Hüseyin; Öner, Cengiz; İlkılıç, Cumali; Hazar, Hanbey
    Bu çalışmanın amacı; bitkisel yağlardan olan kanola yağının önceden ısıtılarak bir dizel motorunda kullanımından kaynaklanan egzoz emisyonlarının nasıl değiştiğini incelemektir. Bu amaçla saf kanola yağı %20 ve %50 oranlarında dizel yakıtı ile karıştırılmış ve bu karışım yakıtlar dört zamanlı, tek silindirli ve hava soğutmalı bir dizel motorda kullanılmıştır. Karışım yakıtlar kullanım sırasında 100o C sıcaklığa kadar ısıtıldıktan sonra kullanılmış ve bu ön ısıtma işleminin dizel motorda ısıl verim, egzoz gazı sıcaklığı, NOx, CO ve duman emisyonlarına etkileri araştırılmıştır. Ön ısıtma işleminin CRO’ nun viskozitesini azalttığı ve daha uygun bir yakıt akışı sağlayarak emisyonlar üzerinde olumlu etki yaptığı sunucuna varılmıştır
  • Öğe
    Dairesel kesitli bir borunun girişine yerleştirilen delikli sabit kanatçıklı dönme üreticinin ısı geçişi ve basınç düşüşüne etkileri
    (Pamukkale Üniversitesi, 2006-02-01) Argunhan, Zeki; Yıldız, Cengiz
    Bu çalışmada iç içe borulu ısı değiştirgecinde farklı delik sayılı dönme üreticilerin ısı transferine ve basınç düşüşüne etkisi deneysel olarak araştırılmıştır. Bu amaçla değiştirgecin 60 mm çapındaki iç borunun girişine 55º kanat açısına sahip ve kanatlarında birer, ikişer, üçer ve dörder adet dairesel delikler bulunan dönme üreticiler yerleştirilerek deneyler yapılmıştır. Bunlar iç borunun girişine rahat takılıp sökülebilecek şekilde dizayn edilmişlerdir. İç borunun içinden sıcak akışkan olarak hava, iç borunun dışından ise soğuk akışkan olarak su geçmektedir.