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Research Project Low Temperature Behavior Of Hma And Sma Mixtures/tas Mastik Asfalt ve Bitümlü Sıcak Karısımların Düsük Sıcaklık Altındaki DavranısıLow temperature cracks in asphalt concrete pavements are commonly seen in the East, interior, and west interior Anatolian regions of turkey where air temperature falls below -20 °C, or so low that the developed thermal stress exceeds the thermal strength of asphalt concrete and causes cracks. Low temperature cracking reduces the roadway's driving comfort by the increased surface roughness due to fracture, leading to the seepage of melting snow and rainfall water into the subgradethrough the surface cracks and causing loss of bearing capacity). Combined with the disruption caused by traffic loading, low temperature cracking weakens the structural integrity of the pavement and eventually increases roadway maintenance and rehabilitation costs. Low temperature cracking is one of the main reasons for pavement deterioration, ranked as the second factor in roadway maintenance and repair costs in the Northern regions (Figure 1). Stone Matrix Asphalt (SMA) has been widely used in turkey highways, it provides stone-on-stone contact and high asphalt content that can increase a pavement’s durability and resistance to rutting and reduce noise. However, drainage of binder and higher primary costs could be mentioned of its disadvantages. Since there is no consensus about the performance of SMA at low temperature, conducting a comprehensive study with different tests on the performance of Stone Matrix Asphalt at low temperatures would be beneficial. This project aims at characterizing the low temperature behavior of the Stone Matrix Asphalt (SMA) and HMA in terms of gradation type,aggregate and asphalt type. Upon completing this proposed project, low temperature performance of SMA would be investigated, and a significant contribution will be provided to achieve long lasting pavements without frequent maintenance and rehabilitation. It is believed that the research outcomes will contribute to the national and international knowledge considering the fact that there is only a limited study available in the literature on low temperature performance of SMA.Research Project Elektrokatalitik Amonyak Üretimi için Ce Katkılı Lafeo3 Perovskit Malzemesinin GeliştirilmesiAmmonia is the second most produced chemical worldwide, which has a wide range of uses in the production of cleaning products, nitrogen-containing chemicals and explosives in sectors such as energy, cooling, textile, fertilizer, medicine. Also, a good source of hydrogen, ammonia has the potential to play an important role in the future hydrogen economy. Ammonia production has thermodynamic limitations and is commercially produced by the Haber-Bosh process at high pressure and high temperature. Electrocatalytic ammonia production processes eliminate thermodynamic limitations and provide ammonia production at atmospheric pressure. Studies on ammonia production by using solid oxide conductors are still ongoing, and research using oxide conducting electrolytes are limited. Ammonia production in oxide conducting electrolytes provides thermodynamically an advantage over the Haber-Bosh process, but the cathode catalyst is also very important for the development of the membrane electrode system. The catalyst to be used in oxide conducting electrolyte is expected to be active for ammonia production, to have high ionic and electrical conductivity, and to have high strength and stability under operating conditions. In addition, the compatibility of the electrolyte material and the thermal expansion coefficient of the catalyst to be used in the system is another important parameter. Perovskite materials have the potential to have these properties, and the properties of perovskites can be improved by adding various metals to their structure. Electrocatalytic studies in the literatüre widely use yttria stabilized zirconia (YSZ) stabilized, which can easily be obtained commercially, as the solid oxide electrolyte material. Within the scope of the proposed project, LaFeO3 that has thermal expansion coefficient close to YSZ will be synthesized and the effectof doping with Ce in different ratios on the katalyst properties will be examined by characterization methods. There are currently no studies in literatüre that use of La1-xCexFeO3 cathode catalyst for the production of ammonia in oxide conducting electrolyte system. As a result of the study, the development of an active and selective cathode catalyst with high ionic and electrical conductivity, compatible with YSZ electrolyte, for the production of ammonia using solid oxide electrolyte will contribute to the literature. Outcomes of this project are planned to be published in national/ international journals and/or presented in national/international conferences.Research Project Synthesis and Polymerization of Monomers Possessing Chemiluminescence Properties and Their Application AreasA novel class of chemiluminescence (KL) compounds was designed, synthesized and characterized; 2,3-dihydro-thieno[3,4-d]pyridazine-1,4-dione (T-Lum), 2,3-dihydro-furo[3,4-d]pyridazine-1,4-dione (FLum) and 2,3-dihydro-pyrrolo[3,4-d]pyridazine-1,4-dione (P-Lum). The KL reaction of the compounds in alkali medium was examined by using hydrogen peroxide and potasium permanganate oxidants and a possible KL mechanism was investigated. Synthesized compounds are especially sensitive to Fe+3 ion and this property makes them amenable to use as iron sensors. Also, the sensitivity of these materials towards iron makes them a promising candidate in forensic area to detect trace amount of blood at crime scene. Compounds are also sensitive both iron and blood samples even at lower concentration. By using the sensitivity of compounds towards hydrogen peroxide, the detection of many analytes will be possible. Beside the KL property, the electrochemiluminescence (EKL) property of the materials makes them very precious. Since the oxidation of pyridazine ring occurs before the aromatic rings, electropolymerization of the functionalized pyrrole, furan and thiophene compounds with pyridazine rings were not possible. To overcome this problem, new compounds, which have lower oxidation potential than that of pyridazine ring, were designed, synthesized and characterized; 5,7-di-tthiophen-2-yl-2,3-dihydro-thieno[3,4- d]pyridazine-1,4-dione (TTT-Lum) and 5,7-di-ethylenedioxythiophene-2-yl-2,3-dihydro-thieno[3,4- d]pyridazine-1,4-dione (ETE-Lum). The materials synthesized in the form of donor-acceptor-donor exhibit both KL and EKL properties, which makes them promising candidates in the analytical chemistry and forensic science. Compounds were polymerized successfully without oxidizing pyridazine ring via electrochemical polymerization (only neat BF3-Et2O solution or 0.1 M LiClO4 or 0.1 M tetrabutylammonium perchlorate dissolved in acetonitrile containing 5% of BF3-Et2O by volume ) and the electrochemical and optical properties were investigated. Electroactive and electrochromic polymeric materials, exhibiting reversible redox behaviours, have lower band gaps between 1.6 and 1.7 eV. Also, the polymer films are very stable; the electroactivity and the EKL properties were remain unchangeable after many cycles. Furthermore, the soluble polymer films in alkali medium with their KL properties will attract many attention in the academic areas.Research Project Sürekli Nanomalzeme Üretimi için Alev Aerosol Reaktör Tasarımı, Kontrolü ve SimülasyonuDue to its advantages compared to the wet chemistry methods, Flame Aerosol Technology is used to produce 90% (by volume) of the commercial nanomaterials continuously in a faster, cheaper way, and in a single step [1-2]. Evolved by combining combustion and aerosol technologies, a large span of materials from salts to metal oxides can be produced by this method [3]. In this technology, the most important issue is to produce the desired phase in the desired purity and morphology, and to understand the effect of the process parameters that control these properties. This is mostly because it takes place at very high temperature, where momentum, heat and mass transfer phenomena take place simultaneouly, as well as the combustion of fuel and the reaction of the metal salts in the flame. In order to apply this fast and high temperature process to the industrial scale, there is a need for well controlled laboratory experiments that allows to produce models which can be used to simulate the experimental results. In this proposal, a well controlled flame reactor will be designed, and the effect of the operation conditions on the final nano particle size, morphology and crystal phase will be investigated. The aim is to control the process conditions in a way that allows the tailor-made nanoparticles especially for heterogeneous catalytic applications. Computational Fluid Dynamics package FLUENT will be used along with a user defined “population balance” model in order to estimate the nanoparticle size, and compared with the experimental results. A new reactor will be designed and constructed with the help of the simulation, and metal oxides (e.g. TiO2, Pd/Co3O4 ) will be produced under different operating conditions. The nanoparticles produced will be characterized for their size and morphology, and the validity of the simulation model will be checked.Research Project Lineer Olmaya Üçlü Schrödinger Denklemi için Yapı Koruyan Sayısal Yöntemler(2016) Aydın, Ayhan; Ertuğ, Sevim-Research Project Plastikleştirilmiş Poli(laktik Asit)’in Alev Dayanımının Fosfor Bazlı Katkı Maddeleri ile GeliştirilmesiThe aim of this study is to improve the flame resistance and toughness of PLA by adding small amounts of different flame retardant additives and plasticizers at the same time. Poly(ethylene glycol) (PEG) was used as a plasticizer. Phosphate-based chemicals as flame retardant additives; ammonium polyphosphate (APP), boron phosphate (BP) and tri-phenyl phosphate (TPP) were used. Within the scope of the project, the synergistic effects of the double and triple compositions of these flame retardant additives were also examined. The mixtures are produced by melt blending and injection molding methods. The effect of the type and composition of flame retardant additives on the properties of PLA composites was determined by various mechanical, thermal and flammability tests.Research Project Donör-akseptör Düzeninde Yeni Bir Bileşik Grubununtasarımı, Sentezi ve İletken Polimerlerinin Uygulama Alanları(2011) Cihaner, Atilla; Tirkeş, Seha; Atak, Samed-Research Project Okzim Türevli Ligandlar İçeren Yeni Plantik(ıı) Komplekslerinin Sentezi, Elektrokimyasal Karakterizasyonu ve Antioksidatif Antikanser Etkileri(2012) Özalp, Şeniz Yaman; Emrullahoğulları, Mustafa; İşgör, Sultan Belgin-Research Project Duygusal Olaylar Kendinden Önce Sunulan Nötr Uyarıcıların Hatırlanması Neden Artırır? Bir Fonksiyonel Manyetik Rezonansgörüntüleme Çalışması(2012) Özçelik, Erol; Gökçay, Didem; Er, Nurhan-Research Project Preparation Of Magnetic Nanoparticles Which Enable The Use Of 18f-fdg As Multi-modal İmaging Agents İn Pet-mrı Applications/18f-fdg Nin Pet-mr Görüntüleme Uygulamalarında Multi-modal Görüntüleme Ajanı Olarak Kullanılmasına Yönelik Manyetik Nanoparçacıkların HazırlanmasıIt is becoming increasingly evident that PET-MRI multi-modal imaging systems have great potential in practical medicine and for basic scientific research. Consequently there is a wide interest in developing proper imaging agents for these applications. Superparamagnetic iron oxide (SPIO) nanoparticles are already, extensively, being used as MRI contrast agents. The labeling of these nanoparticles with radioactive isotopes provides a new generation for MRI agents. Combination of the required properties, in the body of the same sample for both measurement techniques, ensures that both images are coming from the same spot and simultaneously. This approach provides more accurate and reliable data for diagnosis and treatment of the illness. One of the candidates of the applicable radioactive isotopes is 18F, an easily available one and is being produced in our country. However its chemical binding to delivery agents requires several steps of exhaustive chemical treatments. A laboratory/firm which tends to fabricate iron oxide nanoparticles labeled with 18F should reconstruct a new manufacturing plant, which needs a laborious and a quite expensive operation. Instead, a new process, which can convert already available PET contrast agents into PET-MRI agents without requiring any special expertise, would be more practical and economical.
