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Article Citation - WoS: 9Citation - Scopus: 9Sr addition and its effect on the melt cleanliness of A356(Iop Publishing Ltd, 2020) Atakav, Baturalp; Gursoy, Ozen; Erzi, Eray; Tur, Kazim; Dispinar, DeryaStrontium modification of Al-Si alloys has known to have several beneficial effects such as increased feedability, the formation of fibrous Si and increased mechanical properties. However, in the presence of Sr, during melting and holding durations, the oxide structure of the dross may change which leads to several problems during casting operations. In this work, the amount of Sr was changed and the melt was held for 1 h. Reduced Pressure Test (RPT) was used to asses melt quality change and it was found that cleanliness was increased due to the fading of Sr.Article Citation - Scopus: 1Samarium and Yttrium Doping Induced Phase Transitions and Their Effects on the Structural, Optical and Electrical Properties of Nd2sn2< Ceramics(Iop Publishing Ltd, 2019) Saleh, Adli A.; Qasrawi, A. F.; Hamamera, Hanan Z.; Khanfar, Hazem K.; Yumusak, G.In this work, the effects of Sm+3 and Y+3 doping onto the structural, optical and electrical properties of Nd2Sn2O7 are investigated. An atomic content of 3.49% and 4.29% of Sm and Y, respectively, were sufficient to alter the physical properties of the Nd2Sn2O7. Particularly, the Y+3 ionic substitution decreased the lattice constant, narrows the energy band gap, changed the conductivity type from n- to p- type and increased the electrical conductivity by 73 times without changing the cubic nature of structure of the pyrochlore ceramics. On the other hand, Sm+3 ionic substitutions changed the cubic structure to hexagonal or trigonal and forced optical transitions in the infrared range of light. The energy band gap shrunk from 3.40 to 1.40 eV, the defect density is reduced and the electrical conductivity increased by 47 times via Sm doping. These doping agents' makes the neodymium stannate pyrochlore ceramics more appropriates for optoelectronic applications.Article Citation - WoS: 20Citation - Scopus: 20Properties of the Pc(4312) pentaquark and its bottom partner(Iop Publishing Ltd, 2021) Azizi, K.; Sarac, Y.; Sundu, H.We present an analysis of the newly observed pentaquark P-c(4312)(+) to shed light on its quantum numbers. To do that, the QCD sum rules approach is used. The measured mass of this particle is close to the Sigma D-++(c)- threshold and has a small width, which supports the possibility of its being a molecular state. We consider an interpolating current in a molecular form and analyze both the positive and negative parity states with spin-. We also consider the bottom counterpart of the state with similar molecular form. Our mass result for the charm pentaquark state supports that the quantum numbers of the observed state are consistent with J(P) = 1/2(-).Article Citation - WoS: 13Citation - Scopus: 15Induced Scattering Limits on Fast Radio Bursts From Stellar Coronae(Iop Publishing Ltd, 2016) Lyubarsky, Yuri; Ostrovska, SofiyaThe origin of fast radio bursts remains a puzzle. Suggestions have been made that they are produced within the Earth's atmosphere, in stellar coronae, in other galaxies, or at cosmological distances. If they are extraterrestrial, the implied brightness temperature is very high, and therefore the induced scattering places constraints on possible models. In this paper, constraints are obtained on flares from coronae of nearby stars. It is shown that the radio pulses with the observed power could not be generated if the plasma density within and in the nearest vicinity of the source is as high as is necessary to provide the observed dispersion measure. However, one cannot exclude the possibility that the pulses are generated within a bubble with a very low density and pass through the dense plasma only in the outer corona.Article Citation - WoS: 31Citation - Scopus: 34Mechanical, Thermo-Mechanical and Morphological Characterization of Abs Based Composites Loaded With Perlite Mineral(Iop Publishing Ltd, 2020) Alghadi, Aiah Mohamed; Tirkes, Seha; Tayfun, UmitAcrylonitrile-butadiene-styrene (ABS) copolymer was filled with perlite mineral (PER) at four different loading level of 2.5%, 5%, 10% and 15%. ABS/PER composites were produced using lab-scale micro-compounder followed by injection molding process. Mechanical, thermo-mechanical, melt-flow and morphological properties of composites were reported by tensile and impact tests, dynamic mechanical analysis (DMA), melt flow index (MFI) test and scanning electron microscopy (SEM), respectively. Mechanical characterizations revealed that tensile strength, elongation and Youngs? modulus of ABS were improved by PER inclusions. However, impact strength of ABS reduced with increase of PER concentration. Glass transition temperature of ABS displayed increasing trend for %5 concentration of PER. MFI test implied that PER addition caused slight decreasing for MFI value of unfilled ABS. Homogeneous dispersion of PER particles into ABS matrix for their lower loading level was obtained from SEM micrographs of composites. According to findings, 5% PER containing sample exhibited the best performance and it was remarked as the most suitable candidate among fabricated ABS based composites.Conference Object Developments in Technology-Based Courses Contents of Interior Architecture Departments in Turkey(Iop Publishing Ltd, 2020) Aykac, Gokce NurThe introduction of information technologies in space design disciplines begins with the use of the Computer Aided Design concept in those disciplines. Since the first example of CAD tool which was launched in 1963, the ability to design using computers has been a method adopted by architecture and space design disciplines and transferred to the educational context. There were changes and transformations in this method due to the needs created by the developing building technologies. The CAD technology, has been adopted to the space design education in order to support the courses. The CAD which was created for challenging the difficulties in the practicing area and speeding up the process, also takes place among the traditional methods of space design in the Interior Architecture discipline. The possibilities provided by those digitally created spatial mediums, have led to a rotational improvement in both education and practice. In addition, the reflections of technological developments in the social context in last decade on many areas of life have led to the necessity of reorganizing the educational contents. Academic studies conducted in recent years, are designed to include the last technological developments in today's educational contents and to reflect students' interests and commitment to these technologies in direct proportion. Bearing this in mind, the objective of this study is to read out the reflection of the developments mentioned above on the Interior Architecture discipline in Turkey by monitoring the developments in the context of the need of updating the educational contents. In order to meet the social developments and today's skills, space design education must follow the technological context in parallel. Based on these considerations, the studies of Turkey which were examined in this research have been conducted before could be explained as inadequate. In this context, to examine the curriculum of the Interior Architecture departments of Turkey and to monitor the updates mentioned before constitute the main focus of the study. CAD-based courses in the curriculum of the Interior Architecture departments were determined and the contents were examined. These analyses were achieved in the context of the methods, techniques and tools used in the courses, and after, the situation of the information based courses were determined. It was concluded that these courses were transformed in direct proportion in line with the increasing needs in the educational context with the developing technology and updates should continue in the context of meeting today's skills.Conference Object Citation - WoS: 4Citation - Scopus: 4A Material Perspective on Consequence of Deformation Heating During Stamping of Dp Steels(Iop Publishing Ltd, 2017) Simsir, C.; Cetin, B.; Efe, M.; Davut, K.; Bayramin, B.Recent studies showed that, during stamping of high strength steels at industrially relevant production rates, local temperature in the blank may rise up to 200 degrees C - 300 degrees C due to deformation heating. Moreover, die temperature may also rise up to 100 degrees C - 150 degrees C for progressive stamping dies. Based on the common assumption that the blank softens as the temperature increases, thermal softening creates a margin in Forming Limit Diagram (FLD) and therefore the FLD determined at room temperature can safely be used for those cases. In this article, the validity of this assumption on DP590 steel is questioned by high temperature tensile tests (RT - 300 degrees C) at various strain rates (10(-3) s(-1) - 1 s(-1)). The results indicated a decrease both in uniform and total elongation in 200 degrees C - 300 degrees C range together with several other symptoms of Dynamic Strain Aging (DSA) at all strain rates. Concurrent with the DSA, the simulated FLD confirms the lower formability at high temperature and strain rates. Thus, it is concluded FLD determined at RT may not be valid for the investigated steels.Conference Object Citation - WoS: 1Citation - Scopus: 1Investigation of the Ds2*(2573)+< Vertex Via Qcd Sum Rules(Iop Publishing Ltd, 2014) Sarac, Y.; Azizi, K.; Sundu, H.In this work the D-s2*(2573)+D+K-0 vertex is studied and the coupling constant corresponding to the D-s2*(2573)(+) -> (D+K0) transition is calculated. The calculation is performed using three point QCD sum rules method and the value of the coupling constant is obtained as gD(s2)*(DK) = (12.85 +/- 3.85) GeV-1. The coupling constant is also used to calculate the decay width and the branching ratio of the considered transition.Article Citation - WoS: 7Citation - Scopus: 6Tunable Nonlinear Absorption and Optical Limiting Behavior of Nabi(moxw1-x< Single Crystals With Ratio of Molybdenum/Tungsten(Iop Publishing Ltd, 2023) Pepe, Yasemin; Yildiz, Elif Akhuseyin; Isik, Mehmet; Karatay, Ahmet; Gasanly, Nizami; Elmali, AyhanThe compositional effect of Mo/W ratio on linear, nonlinear absorption and optical limiting behavior of the NaBi(MoxW1-xO4)(2) single crystals grown by Czochralski technique was investigated. X-ray diffraction patterns of the studied crystals presented well-defined peaks associated with the tetragonal crystalline structure. The nonlinear absorption performance and optical limiting threshold were determined using an open-aperture Z-scan technique. A theoretical model including one photon absorption (OPA), two photon absorption (TPA) and free carrier absorption was used to determine the nonlinear absorption parameters. All of the results showed that defect states, which strongly affect nonlinear absorption (NA) and optical limiting behaviors, can be tuned with the Mo/W ratio, enabling NaBi(MoxW1-xO4)(2) single crystals to be used in desired optoelectronic applications. Linear optical absorption analysis revealed that bandgap energy and defect states can be tuned by changing the Mo/W ratio in the crystal structure. The obtained results showed that all the studied crystals had NA behavior and the nonlinear absorption coefficient decreased with increasing Mo/W ratio. Sequential TPA is the main NA mechanism for these crystals due to the fact that the incident light energy is lower than the bandgap energies and the existence of the real intermediate state around 2.32 eV.Conference Object Reflections of Memory Boom on the Architectural Researches in Turkey(Iop Publishing Ltd, 2020) Cihangiroglu, Melike SelcanMemory is a notion studied by many different disciplines with its various points of views. Researchers, who examine memory and its sub-categories, discuss this notion through interactions of people within their individual; societal; cultural; and urban contexts. It is possible to observe a considerable increase of researches on the phenomenon of memory in the last two decades. These research increase is labelled in the literature as 'memory-boom'. The term "memory-boom" could be explained as the importance and attention given to the notion of memory in society and the academic world. An example of this 'memory-boom' can be seen in the increasing number of researches after the World War II and then The Holocaust. A similar rise was experienced after the 9/11 World Trade Centre attack. As a result of these incidents, which had a worldwide impact on masses, reasons behind memory-boom started to emerge in some researches. In this study, 'memory-boom' is discussed within the national context of Turkey. Notion of memory has been studied in many researches in Turkey, as in the literature of elsewhere. This study focuses on the rise of academic works in Turkey that examine relations between architectural buildings and memory within the field of architecture, as opposed to researches focusing solely on the concept of memory. The purposes of the study could be explained as twofold: 1) to understand reasons behind the increase of memory researches in Turkey and triggers or reasons that may be affecting these works, 2) to understand reasons of the memory-boom related to architecture and architectural buildings in Turkey. In this context, this study is constructed as a preliminary work, which has limited research universe that encompass academic dissertations in architecture and interior design disciplines, written between years of 2000-2020 in Turkey. Thesis, which are archived at the "Council of Higher Education National Thesis Center" database, are examined within the scope of this study, to be able to demonstrate the relations between architecture and memory-boom. The study has a qualitative, interpretive conceptual framework and it relies on critical readings of the existing literature as a method. It is aimed to understand notable similarities and/or differences between triggering reasons of memory-boom in Turkey and related architectural studies. The study intends to contribute to the literature by drawing attention to the notion of "memory-boom" in national literature and to expand its place in academic works and researches.
