Protection of the historical heritage of İstanbul

Taha Toros Arşivi, Dosya Adı: İstanbul Genel Dokümanlarıİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Edip Cansever:Bezik oynayan kadınlar

Taha Toros Arşivi, Dosya No: 20-Edip-Turgut-Hasan Ferit CanseverUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010

Unraveling the nature of magnetism of the 5d4\boldsymbol{d^4} double perovskite Ba2_2YIrO6_6

We report electron spin resonance (ESR) spectroscopy results on the double perovskite Ba$_2$YIrO$_6$. On general grounds, this material is expected to be nonmagnetic due to the strong coupling of the spin and orbital momenta of Ir$^{5+}$ (5$d^4$) ions. However, controversial experimental reports on either strong antiferromagnetism with static order at low temperatures or just a weakly paramagnetic behavior have triggered a discussion on the breakdown of the generally accepted scenario of the strongly spin-orbit coupled ground states in the 5$d^4$ iridates and the emergence of a novel exotic magnetic state. Our data evidence that the magnetism of the studied material is solely due to a few percent of Ir$^{4+}$ and Ir$^{6+}$ magnetic defects while the regular Ir$^{5+}$ sites remain nonmagnetic. Remarkably, the defect Ir$^{6+}$ species manifest magnetic correlations in the ESR spectra at $T\lesssim 20$ K suggesting a long-range character of superexchange in the double prevoskites as proposed by recent theories

[Turgut Cansever]

Taha Toros Arşivi, Dosya No: 20-Edip-Turgut-Hasan Ferit CanseverUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010

The iridium double perovskite Sr2YIrO6 revisited: A combined structural and specific heat study

Recently, the iridate double perovskite Sr$_2$YIrO$_6$ has attracted considerable attention due to the report of unexpected magnetism in this Ir$^{5+}$ (5d$^4$) material, in which according to the J$_{eff}$ model, a non-magnetic ground state is expected. However, in recent works on polycrystalline samples of the series Ba$_{2-x}$Sr$_x$YIrO$_6$ no indication of magnetic transitions have been found. We present a structural, magnetic and thermodynamic characterization of Sr$_2$YIrO$_6$ single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat. Here, we demonstrate the clue role of single crystal X-ray diffraction on the structural characterization of the Sr$_2$YIrO$_6$ double perovskite crystals by reporting the detection of a $\sqrt{2}a \times \sqrt{2}a \times 1c$ supercell, where $a$, $b$ and $c$ are the unit cell dimensions of the reported monoclinic subcell. In agreement with the expected non-magnetic ground state of Ir$^{5+}$ (5d$^4$) in Sr$_2$YIrO$_6$, no magnetic transition is observed down to 430~mK. Moreover, our results suggest that the low temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order of $n \sim 0.5(2)$ \%. These impurities lead to non-negligible spin correlations, which nonetheless, are not associated with long-range magnetic ordering.Comment: 20 pages, 10 figure

Language structure of primary-process thinking

Thesis (Ph.D.)--Boston UniversityThis research was formulated within the framework of psychoanalytic theory and deals with the grammatical structure of primary-processing thinking investigated in a particular stae of weakened ego controls (alcohol intoxication). In line with Freud's and Rapaport's formulations on cognitive processes, two types of thinking are differentiated: Primary-process thinking (ideation) and secondary-process thinking (thought). Ideation is characterized as autistic, egocentric, and affect-laden. It is oriented to the immediate present, and does not consider past experiences or future possibilites. It lacks spatial, temporal, and causal organization, does not concern itself with the relations of time and space, and fails to make a definite estimation or evaluation of events and external reality. It is undifferentiated, diffuse, and vague. Since it abides by the laws of syncretic mechanisms, it manifests itself in symbolic forms and when expressed in speech, it is fragmented and disorganized. According to psychoanalytic theory, the primary thought processes can be observed in states of weakened ego controls, such as dreams, psychosis or sometimes neurosis [TRUNCATED

Design of a Microstrip Bandpass Filter for 3.1-10.6 GHz Uwb Systems

In this thesis, ultra-wideband (UWB) microwave filters and design challenges are studied and, a microstrip UWB filter prototype design is presented. The UWB bandpass filter operating in the 3.6 GHz to 10.6 GHz frequency band is targeted to comply with the FCC spectral mask for UWB systems. The prototype filter is composed of quarter-wavelength spaced shunt stub transmission lines. The circuit is first simulated and optimized by using AWR DE simulation software tool. Then Sonnet EM Simulation and CST EM Simulation Tools are further utilized to obtain more accurate simulated results. The fabricated microstrip UWB bandpass filter is then measured using a vector network analyzer and results are presented. The prototype built can be used in UWB communications or localization systems