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Herein, a modified solid state synthesis of Na0.67Mn0.5Fe0.5O2 and the results of a detailed investigation of the structural and magnetic properties via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis are reported. The magnetic properties of Na0.67Mn0.5Fe0.5O2 do not fit the Curie-Weiss law and a model regarding the spin configuration of the Mn and Fe ions and a possible ferrimagnetic order is suggested. Electrochemical measurements and ex situ structural analysis of the cathode material confirm the reversible structural transitions for the cells charged up to 4.0 V. Environmental temperature-dependent electrochemical measurements reveal a strong temperature dependence of both, the initial capacity and the capacity retention. Ex situ SEM, FTIR, and XRD studies on the battery membrane verify the formation of a Na2CO3 phase on the membrane, which blocks the Na ion diffusion through membrane pores and is responsible for the capacity fade for this compound.

In this study, we report the synthesis of SrCo1-xRuxO3- nominal compositions, where x=0.0-1.0, using solid-state reaction technique. XRD analysis confirms the structure of x=0 sample as hexagonal Sr6Co5O15. As the Co ions are substituted by Ru, a two-phase structure (hexagonal R32 and orthorhombic Pbnm) emerges up to x0.5. As the Ru content is increased further, the hexagonal R32 phase disappears completely and an orthorhombic Pbnm phase becomes the main phase. SEM images show that grain size of the samples decreases with increasing Ru content. Temperature-dependent electrical conductivity studies indicate upon Ru substitution in the nominal SrCo1-xRuxO3- compounds, resistivity decreases due to appearance of metallic SrRuO3 phase. The cyclic voltammogram (CV) of the samples show capacitive properties upon Ru substitution. The cycle measurements of the capacitors yield promising results for potential supercapacitor applications.

Güncel hayatımızda, cep telefonları ve diz üstü bilgisayarlar gibi taşınabilir elektronik cihazların sayısının hızla artması ile yüksek enerji yoğunluklu, hafif, kompakt ve şarj edilebilir pillerle ilgili araştırmalar yoğunlaşmıştır. Bu makalede Li-iyon pillerinde en çok kullanılan katot malzemesi olan LiCoO2’de Co yerine Mn katkılaması yapılarak, bu katkılamanın kristal yapı ve morfolojik özellikleri nasıl etkilediği incelenmiştir. LiCo1-xMnxO2 bileşikleri x=0.1 aralığında katıhal reaksiyonları ile üretilmiş ve örneklerin yapısal ve morfolojik özellikleri XRD ve SEM teknikleri ile araştırılmıştır. Bu çalışmalar sonucunda 0≤x≤0.2 örneklerinde LiCoO2 fazı kararlı faz durumunda iken, Mn miktarının artması ile Li2MnO3ve LiMn2O4 spinel fazı ortaya çıkmıştır.

Combined neutron and x-ray diffraction experiments demonstrate the formation of a low-temperature minority tetragonal phase in Ba$_{0.76}$K$_{0.24}$Fe$_2$As$_2$ in addition to the majority magnetic, orthorhombic phase. A coincident enhancement in the magnetic ($\frac{1}{2}$ $\frac{1}{2}$ 1) peaks shows that this minority phase is of the same type that was observed in Ba$_{1-x}$Na$_x$Fe$_2$As$_2$ ($0.24 \leq x \leq 0.28$), in which the magnetic moments reorient along the $c$-axis. This is evidence that the tetragonal magnetic phase is a universal feature of the hole-doped iron-based superconductors., Comment: 6 pages, 7 figures

We present neutron diffraction analysis of BaFe$_2$(As$_{1-x}$P$_x$)$_2$ over a wide temperature (10 to 300 K) and compositional ($0.11 \leq x \leq 0.79$) range, including the normal state, the magnetically ordered state, and the superconducting state. The paramagnetic to spin-density wave and orthorhombic to tetragonal transitions are first order and coincident within the sensitivity of our measurements ($\sim 0.5$ K). Extrapolation of the orthorhombic order parameter down to zero suggests that structural quantum criticality cannot exist at compositions higher than $x = 0.28$, which is much lower than values determined using other methods, but in good agreement with our observations of the actual phase stability range. The onset of spin-density wave order shows a stronger structural anomaly than the charge-doped system in the form of an enhancement of the $c/a$ ratio below the transition., Comment: 10 pages, 7 figures, 2 tables

We report the results of a systematic investigation of the phase diagram of the iron-based superconductor system, Ba1-xNaxFe2As2, from x = 0.1 to x = 1.0 using high resolution neutron and x-ray diffraction and magnetization measurements. We find that the coincident structural and magnetic phase transition to an orthorhombic (O) structure with space group Fmmm and a striped antiferromagnet (AF) with space group F(C)mm'm' in Ba1-xNaxFe2As2 is of first order. A complete suppression of the magnetic phase is observed by x = 0.30, and bulk superconductivity occurs at a critical concentration near 0.15. We compare the new findings to the previously reported results of the hole-doped Ba1-xKxFe2As2 solid solution in order to resolve the differing effects of band filling and A-site cation size on the properties of the magnetic and superconducting ground states. The substantial size difference between Na and K causes various changes in the lattice trends, yet the overarching property phase diagram from the Ba1-xKxFe2As2 phase diagram carries over to the Ba1-xNaxFe2As2 solid solution. We note that the composition dependence of the c axis turns over from positive to negative around x = 0.35, unlike the K-substituted materials. We show that this can be understood by invoking steric effects; primarily the Fe2As2 layer shape is dictated mostly by the electronic filling, which secondarily induces an interlayer spacing adjusted to compensate for the given cation volume. This exemplifies the primacy of even subtle features in the Fe2As2 layer in controlling both the structure and properties in the uncollapsed 122 phases., 10 pages, 12 figures, 2 tables

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır. Araştırma, ilköğretim altıncı sınıf öğrencilerinin yapım eklerini öğrenmesinde reklam filmlerinin etkililiğini tespit etmek, yeni ve yaratıcı bir yaklaşım olarak reklam filmlerinin de Türkçe dersinde öğretim tekniği olarak kullanılabilirliğini ölçmek amacıyla yapılmıştır. Uygulama için Sakarya ili Hendek ilçesinde bir devlet ilköğretim okulu seçilmiş ve okulun altıncı sınıf öğrencilerinden biri deney diğeri kontrol grubu olmak üzere iki grup oluşturulmuştur. Gruplar otuz öğrenciden oluşmakta olup toplamda altmış kişi olan öğrenciler örneklem grubumuzu oluşturmaktadır. Deney ve kontrol grupları random ( seçkisiz örnekleme ) yöntemiyle belirlenmiştir.Araştırmada ?ön test, son test kontrol gruplu deneme modeli? kullanılmıştır. Sözcükte yapı konusu, araştırmacı tarafından hazırlanan reklam filmleriyle deney grubunda işlenmiş, kontrol grubunda ise geleneksel yöntem kullanılarak işlenmiştir. Araştırmanın başında ve sonunda gruplara ?Yapım Ekleri Bilgi Testi? ve ?Tutum Ölçeği? uygulanmıştır.Araştırma sonucu elde edilen bulgular doğrultusunda, reklam filmleriyle dersin işlendiği deney grubu öğrencileri ile geleneksel yöntemin uygulandığı kontrol grubu öğrencilerinin ?Yapım Ekleri Bilgi Testi? son test puan ortalamaları arasında deney grubunun lehine anlamlı fark olduğu görülmüştür. Öğrencilerin son test tutum puanları dikkate alındığında deney grubu ve kontrol grubu öğrencilerinin son test tutum puanlarında reklam filmleriyle dersin işlendiği deney grubunun lehine anlamlı fark olduğu ortaya çıkmıştır.Araştırma sonunda reklam filmlerinin Türkçe dersinde kullanılmasının, öğrencilerin hem akademik başarılarına hem de tutumlarına yönelik olarak etkili olduğu sonucu ortaya çıkarılmıştır.Anahtar Kelimeler: Türkçe Eğitimi, Dil Bilgisi Öğretimi, Reklam Filmleri, Yapım Ekleri. The research was carrried out for primary 6th graders to determine the effectiveness of commercial films in learning derivational affix, also as a new and innovative approach, to measure the availability of commercial films in Turkish language lessons as a teaching technique. For application, a public school district of the province of Sakarya ditch was choosen and the school?s sixth grader students selected one or two groups, including the experimental and control groups.Group consist of 30 students in total sample of students who constituted our sample group of 60 people. Experimental and control groups was determined randomly.In this research, ' the experimental model as pre-test post-test control group ' was used. The word structure was processed in the experinmental group using the advertising films prepared by the researcher, but processed in control group using the traditional methods. At the beginning and end of the research, groups were applied to have the `knowledge test about affixes' and 'attitude scale?.According to findings from the research, there were significant differences between the two groups? students? final test scores about `Test of knowledge affixes?, in which the course was committed for the experiment group using method of advertising films, and the control group using traditional methods. Considering the post-test attitude scores of students, experimental group and control group students? post-test attitude scores proved that there was really significant difference in favor of experimental group, in which the course was committed with advertising films.At the end of the research, using commercials in Turkish language course helped learners to be effective in academic success as well as attitudes.Key words: Turkish Education, Teaching Grammar, Advertising Films, Derivational Affix

Superconductivity in iron selenides has experienced a rapid growth, but not without major inconsistencies in the reported properties. For alkali-intercalated iron selenides, even the structure of the superconducting phase is a subject of debate, in part because the onset of superconductivity is affected much more delicately by stoichiometry and preparation than in cuprate or pnictide superconductors. If high-quality, pure, superconducting intercalated iron selenides are ever to be made, the intertwined physics and chemistry must be explained by systematic studies of how these materials form and by and identifying the many coexisting phases. To that end, we prepared pure K_2Fe_4Se_5 powder and superconductors in the K_xFe_{2-y}Se_2 system, and examined differences in their structures by high-resolution synchrotron and single-crystal x-ray diffraction. We found four distinct phases: semiconducting K_2Fe_4Se_5, a metallic superconducting phase K_xFe_2Se_2 with x ranging from 0.38 to 0.58, an insulator KFe_{1.6}Se_2 with no vacancy ordering, and an oxidized phase K_{0.51(5)}Fe_{0.70(2)}Se that forms the PbClF structure upon exposure to moisture. We find that the vacancy-ordered phase K_2Fe_4Se_5 does not become superconducting by doping, but the distinct iron-rich minority phase K_xFe_2Se_2 precipitates from single crystals upon cooling from above the vacancy ordering temperature. This coexistence of metallic and semiconducting phases explains a broad maximum in resistivity around 100 K. Further studies to understand the solubility of excess Fe in the K_xFe_{2-y}Se_2 structure will shed light on the maximum fraction of superconducting K_xFe_2Se_2 that can be obtained by solid state synthesis., Comment: 12 pages, 16 figures, supplemental material

We report the results of a systematic investigation of the phase diagram of the iron-based superconductor, Ba1-xKxFe2As2, from x = 0 to x = 1.0 using high resolution neutron and x-ray diffraction and magnetization measurements. The polycrystalline samples were prepared with an estimated compositional variation of \Deltax, Comment: Accepted for publication in Physical Review B; 12 pages, 13 figures, 2 tables

We report a high resolution neutron diffraction investigation of the coupling of structural and magnetic transitions in Ba1xKxFe2As2. The tetragonal-orthorhombic and antiferromagnetic transitions are suppressed with potassium-doping, falling to zero at x ~ 0.24., Comment: 4 pages, 5 figures