Multiple Orbitoides d’Orbigny lineages in the Maastrichtian? Data from the Central Sakarya Basin (Turkey) and Arabian Platform successions (Southeastern Turkey and Oman)

The standard reconstruction of species of Orbitoides d’Orbigny into a single lineage during the late Santonian to the end of the Maastrichtian is based upon morphometric data from Western Europe. An irreversible increase in the size of the embryonic apparatus, and the formation of a greater number of epi-embryonic chamberlets (EPC) with time, is regarded as the main evolutionary trends used in species discrimination. However, data from Maastrichtian Orbitoides assemblages from Central Turkey and the Arabian Platform margin (Southeastern Turkey and Oman) are not consistent with this record. The Maastrichtian Besni Formation of the Arabian Platform margin in Southeastern Turkey yields invariably biconvex specimens, with small, tri- to quadrilocular embryons and a small number of EPC, comparable to late Campanian Orbitoides medius (d’Archiac). The upper Maastrichtian Taraklı Formation from the Sakarya Basin of Central Turkey contains two distinct, yet closely associated forms of Orbitoides, easily differentiated by both external and internal features. Flat to biconcave specimens possess a small, tri- to quadrilocular embryonic apparatus of Orbitoides medius-type and a small number of EPC, whereas biconvex specimens possess a large, predominantly bilocular embryonic apparatus, and were assigned to Orbitoides ex. interc. gruenbachensis Papp–apiculatus Schlumberger based on morphometry. The flat to biconcave specimens belong to a long overlooked species Orbitoides pamiri Meriç, originally described from the late Maastrichtian of the Tauride Mountains in SW Turkey. This species is herein interpreted to be an offshoot from the main Orbitoides lineage during the Maastrichtian, as are forms that we term Orbitoides ‘medius’, since they recall this species, yet are younger than normal occurrence with the accepted morphometrically defined lineage. The consistent correlation between the external and internal test features in O. pamiri implies that the shape of the test is not an ecophenotypic variation, but appears to be biologically controlled. We, therefore, postulate that more than one lineage of Orbitoides exists during the Maastrichtian, with a lineage that includes O. ‘medius’ and O. pamiri displaying retrograde evolutionary features

Dielectric Properties of Calcium Phosphate Ceramics

Calcium phosphate ceramics with various Ca/P ratios of 1, 2, 3, 4 and 8 were synthesized via sol-gel route. The effects of Ca/P molar ratio on structural, morphological, dielectric and antimicrobial properties were investigated in detail using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy and dielectric measurements. The Ca/P molar ratio significantly affects the crystal structure and phase composition. The crystallite size, lattice parameters and volume of the unit cell were remarkably affected by the change in the Ca/P molar ratio. The microstructure is changed with increasing the Ca/P molar ratio. The relative permittivity and alternating current conductivity gradually decrease for the samples having the Ca/P ratios higher than 2. The dielectric loss decreases gradually with the increase of the molar ratio of Ca/P.DOI: http://dx.doi.org/10.5755/j01.ms.22.1.7222</p

Crystallinity Improvement of Co3O4 by Adding Thiourea

Tricobalt tetraoxide (Co3O4) samples having different thiourea/Co molar ratio of 0, 5 and 10 were prepared by wet chemical synthesis. The effects of thiourea content on the crystal structure-related parameters of Co3O4 were determined. The increase in the amount of thiourea caused a gradual decrease in the lattice parameters and specific surface area and an increase in the crystallinity and crystallite size. The experimental analysis results showed that thiourea content can be used to control the crystal structure-related parameters of Co3O4

Malva neglecta Wallr. (Ebegümeci)’nın In vitro Biyoaktif ve Fitokimyasal Özellikleri

M. neglecta çok yıllık otsu bir bitkidir ve Malvaceae familyasında yer almaktadır. Bu bitki ülkemizde her türlü toprakta kendiliğinden yetişir ve taze sürgünleri ile yaprakları sebze olarak tüketilir. Bu çalışmada M. neglecta toprak üstü kısımlarının su, etanol ve metanol ekstraktlarının antiradikal, antimikrobiyal, antikanser ve fitokimyasal içerikleri incelenmiştir. Elde edilen sonuçlara göre, M. neglecta toprak üstü kısımlarının yüksek antiradikal, antimikrobiyal, antikanser aktiviteye ve fitokimyasal içeriğe sahip olduğu anlaşılmıştır

Synthesis and Structural Characterization of Y-doped Pyramidal ZnO Powders

The present study focuses on the structural changes in ZnO powder induced by doping of a rare earth metal of Y. For this aim, we synthesized four ZnO samples with different Y-content using the combustion reaction method. X-ray powder diffraction (XRPD) technique and scanning electron microscopy (SEM) results confirm that the as-investigated structural parameters and morphology of the ZnO structure were affected directly by the concentration of Y dopant. For each Y-doped sample, randomly-oriented pyramidal morphology and the formation of a minority phase of Y2O3 were observed. A gradual increase in both lattice parameters and unit cell volume was detected with increasing Y content. All samples were found to be thermally stable in the temperature interval of 25-950 °C

Li2O-Al2O3-SiO2-NiO cam-seramiğinin üretimi ve karakterizasyonu

Bu çalışmada, Li2O-Al2O3-SiO2-NiO cam-seramik numunesi geleneksel yöntem kullanılarak üretildi ve X-ışını kırınımı (XRD) analizi, Fourier dönüşümlü kızılötesi (FTIR) spektroskopisi, diferansiyel termal analiz (DTA), termogravimetrik analiz (TGA) ve taramalı elektron mikroskopisi teknikleri kullanılarak karakterize edildi. Numunenin iki fazlı çok kristalli bir yapıya sahip olduğu görüldü. Fonksiyonel gruplar tespit edildi. Üretilen numunenin oda sıcaklığı ile 1000 °C aralığında termal davranışı araştırıldı. Numunenin morfolojisi incelendi ve numune içerisinde herhangi bir safsızlık tespit edilemedi

A Palaeontological Geosite Example: Hasanaga Stream, Akcadag, Malatya

WOS: 000434457700008Rock, mineral, fossil associations, structure, geological section, landforms or a part of land which they represent current or former geological process, event or a specialty is defined geosite. Some geologic units containing fossil associations and outcropping along Hasanaga Stream located in the northwest of Akcadag which is a settlement of Malatya city in Eastern Anatolia Region, is seen as a good example to this definition. The age of the geological units that outcrop along Hasanaga Stream ranges from Mesozoic to Quaternary. Diversity of Tertiary sedimentary units along Hasanaga Stream is represented by Korgantepe, Yenice and Asartepe members of Eocene Darende Formation, Oligocene Muratli Formation and Lower Miocene Alibonca Formation. The geological units constitute a regular sequence range from Lutetian to Oligocene in Hasanaga Stream. Their abundant larger benthic foraminifera such as Nummulites, Alveolina and Discocyclina are the subject of this study and they have been evaluated within the scope of geological heritage. Along the Hasanaga stream also, there are many caves having traces of life in some of them, on both sides of the valley, in different sizes. Diversity of larger benthic foraminifera and karstic formations increases the scientific importance of the district