Foraminiferal biostratigraphy and sequence stratigraphy of peritidal carbonates at the Triassic-Jurassic boundary (Karaburun Peninsula, Western Turkey)

Continuous shallow marine carbonates spanning the Triassic-Jurassic boundary are exposed in the Karaburun Peninsula, Western Turkey. The studied section (Tahtaiskele section) consists of Upper Triassic cyclic shallow marine carbonates intercalated with clastics overlain by Lower Liassic carbonates. Based on the microfacies stacking patterns, three main types of shallowing-upward cycles have been recognized. Cycles are mostly composed of subtidal facies at the bottom, intertidal/supratidal facies and/or subaerial exposure structures at the top. The duration of the cycles suggests that cycles were driven by the precessional Milankovitch rhytmicity. In the sequence stratigraphic frame of the Tahtaiskele section 4 sequence boundaries were detected and globally correlated. The first sequence boundary is located at the Alaunian-Sevatian boundary nearly coinciding with the first appearance of Triasina hantkeni. The second falls in the Rhaetian corresponding to a major sea level fall which led to the invasion of forced regressive siliciclastic deposits over the peritidal carbonates. The third occurs close to the T/J boundary and the fourth lies slightly above the base of the Jurassic. In the studied section, extinction, survival and recovery intervals have been recognized based on the stratigraphic occurrence patterns of benthic foraminifera and algae. Foraminifers became nearly totally extinct in the inner carbonate shelves at the Triassic-Jurassic boundary and an interval of approximately 0.5 my passed before the begining of the recovery of Jurassic foraminifera

Phase transformation and paired-plate precipitate formation in Pb 0.91 La 0.09 Zr 0.65 Ti 0.35 O 3 films grown on sapphire substrates

Abstract We report on the phase transformation behavior of Pb 0.91 La 0.09 Zr 0.65 Ti 0.35 O 3 (9/65/35) PLZT films grown on rsapphire substrates via rf-magnetron sputtering. A complex microstructure results in these films depending on deposition and annealing conditions. A random equiaxed polycrystalline grain morphology was observed after rapid thermal annealing or furnace annealing when the as-deposited films were predominantly pyrochlore. Precipitate formation (100-150 nm) was observed in PLZT films that were deposited at temperatures in excess of 4901C with a perovskite structure, after furnace annealing at 7001C. We believe that this is related to internal stresses in the films due to both the lattice mismatch and the thermal expansion mismatch between the PLZT film and the sapphire substrate.

Properties of Ceria Based Novel Anode Nanopowders Synthesized by Glycine-Nitrate Process

Novel anode nanopowder materials consisting of ceria-based components synthesized by glycine-nitrate process were investigated for solid oxide fuel cells. Glycine-nitrate process involves a self-combustion reaction at 220C of water-based nitrate and glycine solutions which subsequently can reach up to 1200°C. The resulting morphology, the size of particles and the formation of crystalline phases were characterized by differential scanning calorimetry, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, the Brunauer-Emmett-Teller method and Nanosizer. It was determined that dopants in ceria such as Co, Ni, Cu, V and Fe had significant effect on the morphology and size. The size distribution measured by Nanosizer was 50-600 nm, transmission electron microscopy, 5-200 nm and the Brunauer-Emmett-Teller method 100-120 nm and specific surface area of powders in the range 67.45-72.05 $m^2 g^{-1}$ as measured by the Brunauer-Emmett-Teller method. Particles were observed to have spherical structures for Cu and Fe doped powders and rod-shaped in a porous tuff microstructure for those doped with Co and Ni. Vanadium doping helped to decrease the porosity and initiated the process of spheroidization of particles

Anxiety among adolescents and its affect on orthodontic compliance

Background: Investigations have suggested that poor compliance could be an indicator of poor relationship with family and could be related to the person′s personality traits. Aim: The aim of this study was to determine the effect of parents attitude, the anxiety during treatment and self-confidence/self-care of the patient on cooperation during orthodontic treatment. Materials and Methods: The study material consisted of questionnaires completed by 82 adolescent patients and their parents. The patients were divided into two groups of 42 compliant and 40 non-compliant patients. The above-mentioned questionnaries were State-Trait Anxiety Inventory-STAI, Piers-Harris Children′s Self Concept Scale and The Exercise of Self-Care Agency for the patients and Mc Master Family Assessment Device and Parental Attitude Research Instrument-PARI for the parents. Results: The problem solving and caring attitude of the father and his determinative role in the family had a positive infulence on the compliance of the child. The patients who showed better compliance also had a lower state of anxiety, which could also be explained by the positive effect of the attitude of the father in the family. Conclusion: It would be useful to overcome the increased state of anxiety of the child in the orthodontic clinic by using educational and relaxation techniques. Besides, it would be wise to ask the father to be present at the first appointment during part of the education of the child

Recent Rrogresses on Solution-Processed Silver Nanowire Based Transparent Conducting Electrodes for Organic Solar Cells

Organic photovoltaics (OPVs) are considered as a future alternative for conventional silicon based solar cells, owing to their low cost, ease of production and high-throughput. The transparent conducting electrode (TCE) is a fundamental component of OPVs. Traditionally, indium tin oxide (ITO) has been mainly utilized as a TCE in OPV applications due to its relatively high transparency and low sheet resistance. However, increasing demand for the optoelectronic devices has led to large fluctuations in ITO prices in the past decade and ITO is known to account more than 50% of the total cost of OPV devices. Thus, it is believed that development of solution-processable alternative materials is of great importance in reducing the cost of OPVs. Numerous materials, including silver nanowires, carbon nanotubes, graphene and conducting polymers, have been offered as replacements for ITO. This article reviews recent progress on fabrication of TCE via solution based coating techniques of silver nanowires (Ag NWs). In addition, performance of the Ag NWs based TCE in OPVs is summarized. Finally, we explore the future outlook for Ag NWs based TCE at the end of the review. © 2017 Elsevier LtdNational Research Foundation of Korea: NRF-2015R1C1A1A02036599 111M510The authors would like to acknowledge the financial support from T?BITAK, Turkey (Grant No: 111M510) and National Research Foundation of Korea, South Korea (NRF-2015R1C1A1A02036599)

Properties of Ceria Based Novel Anode Nanopowders Synthesized by GlycineNitrate Process

Novel anode nanopowder materials consisting of ceria-based components synthesized by glycinenitrate process were investigated for solid oxide fuel cells. Glycinenitrate process involves a self-combustion reaction at 220 • C of water-based nitrate and glycine solutions which subsequently can reach up to 1200 • C. The resulting morphology, the size of particles and the formation of crystalline phases were characterized by dierential scanning calorimetry, X-ray diraction, transmission electron microscopy, scanning electron microscopy, the BrunauerEmmettTeller method and Nanosizer. It was determined that dopants in ceria such as Co, Ni, Cu, V and Fe had signicant eect on the morphology and size. The size distribution measured by Nanosizer was 50600 nm, transmission electron microscopy, 5200 nm and the BrunauerEmmettTeller method 100120 nm and specic surface area of powders in the range 67.4572.05 m 2 g −1 as measured by the BrunauerEmmettTeller method. Particles were observed to have spherical structures for Cu and Fe doped powders and rod-shaped in a porous tu microstructure for those doped with Co and Ni. Vanadium doping helped to decrease the porosity and initiated the process of spheroidization of particles