Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Search Results

Now showing 1 - 10 of 18
  • Book Part
    Citation - Scopus: 5
    Turmeric Starch: Structure, Functionality, and Applications
    (Elsevier, 2023) Rasmi, Y.; Demir, Mustafa Muammer; Kırboğa, K.K.; Tekin, B.; Demir, M.
    For many years, starch has been a subject of never-ending study. It is a relatively affordable substance widely used in food and non-food applications. Fresh rhizomes of Curcuma longa L. and Curcuma caesia extract turmeric starch (Zingiberaceae). Turmeric starch is a common food ingredient used in the thickening of soups and making syrups and other sugars. It is easily modified and finds many uses in industries such as adhesives, paper products, anti-sticking agents, and textile manufacturing. Morphological characteristics such as the shape and size of starch granules vary significantly, and further studies are expected for Turmeric starch, with promising results and increasing the usefulness of starches in industries. This book chapter outlines recent developments in understanding starch isolation, chemical composition, morphology, pasting, rheological and thermal characteristics, and various applications of turmeric starch. Potential applications of oat starches are also reviewed. © 2024 Elsevier Inc. All rights reserved.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Characterization of a Pearlescent Biaxially Oriented Multilayer Polypropylene Film
    (Lviv Polytechnic National University, 2015) Arkış, Esen; Çetinkaya, Hayrullah; Kurtuluş, Işıl; Ulucan, Utku; Aytaç, Arda; Balcı, Beste; Balköse, Devrim
    The morphology, composition, optical, thermal and mechanical properties of a commercial pearlescent and multilayer biaxially oriented polypropylene (BOPP) films were determined. The structure and orientation of BOPP films were confirmed by FTIR spectroscopy, X-ray diffraction and EDX analysis. The films surface roughness was determined by AFM method. The tensile strength of the films was determined in machine and transverse directions.
  • Other
    Erratum To: Mbe-Grown Cdte Layers on Gaas With In-Assisted Thermal Deoxidation
    (Springer Verlag, 2016) Arı, Ozan; Bilgilisoy, Elif; Özçeri, Elif; Selamet, Yusuf
  • Article
    Citation - WoS: 6
    Citation - Scopus: 5
    Mbe-Grown Cdte Layers on Gaas With In-Assisted Thermal Deoxidation
    (Springer Verlag, 2016) Arı, Ozan; Bilgilisoy, Elif; Özçeri, Elif; Selamet, Yusuf
    Molecular beam epitaxy (MBE) growth of thin (∼2 μm) CdTe layers characterized by high crystal quality and low defect density on lattice mismatched substrates, such as GaAs and Si, has thus far been difficult to achieve. In this work, we report the effects of in situ thermal deoxidation under In and As4 overpressure prior to the CdTe growth on epiready GaAs(211)B wafers, aiming to enhance CdTe crystal quality. Thermally deoxidized GaAs samples were analyzed using in situ reflection high energy electron diffraction, along with ex situ x-ray photo-electron spectroscopy (XPS) and atomic force microscopy. MBE-grown CdTe layers were characterized using x-ray diffraction (XRD) and Everson-type wet chemical defect decoration etching. We found that In-assisted desorption allowed for easier surface preparation and resulted in a smoother surface compared to As-assisted surface preparation. By applying In-assisted thermal deoxidation to GaAs substrates prior to the CdTe growth, we have obtained single crystal CdTe films with a CdTe(422) XRD rocking curve with a full-width half-maximum value of 130.8 arc-s and etch pit density of 4 × 106 cm−2 for 2.54 μm thickness. We confirmed, by XPS analysis, no In contamination on the thermally deoxidized surface.
  • Conference Object
    Citation - WoS: 33
    Citation - Scopus: 35
    Effects of Physical Growth Conditions on the Structural and Optical Properties of Sputtered Grown Thin Hfo2 Films
    (Elsevier Ltd., 2011) Aygün, Gülnur; Cantaş, Ayten; Şimşek, Yılmaz; Turan, Raşit
    HfO2 thin films were prepared by reactive DC magnetron sputtering technique on (100) p-Si substrate. The effects of O2/Ar ratio, substrate temperature, sputtering power on the structural properties of HfO2 grown films were studied by Spectroscopic Ellipsometer (SE), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectrum, and X-ray photoelectron spectroscopy (XPS) depth profiling techniques. The results show that the formation of a SiOx suboxide layer at the HfO2/Si interface is unavoidable. The HfO2 thickness and suboxide formation are highly affected by the growth parameters such as sputtering power, O 2/Ar gas ratio during sputtering, and substrate temperature. XRD spectra show that the deposited films have (111) monoclinic phase of HfO 2, which is also supported by FTIR spectra. XPS depth profiling spectra shows that highly reactive sputtered Hf atoms consume some of the oxygen atoms from the underlying SiO2 to form HfO2, leaving Si-Si bonds behind. © 2010 Elsevier B.V. All rights reserved.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 11
    The Effects of Sb Substitution on Structural Properties in Yba 2cu 3o 7 Superconductors
    (Springer Verlag, 2011) Akyüz, Gönül B.; Kocabaş, Kemal; Yıldız, Aylin; Özyüzer, Lütfi; Çiftçioglu, Muhsin
    In this study, the effects of partial Sb 3+ ion substitutions for the Y sites and the Cu sites on the superconducting properties of YBa 2Cu 3O y (Y123) ceramic superconductors were investigated. The samples were prepared by the conventional solid-state reaction method and the properties of the samples were investigated by means of X-ray diffraction, AC magnetic susceptibility measurements, scanning electron microscope, and energy dispersive X-ray analysis. The critical temperatures were determined to be in the range of 80-92 K for both Systems I and II. It was found that Sb-addition leads to the formation of the non-superconducting YBa 2SbO 6 phase, which has a negative effect on the critical temperature, since the highest critical temperature was measured for pure Y123. However, the increasing substitution level has a negligible effect on the X-ray diffraction analysis peak intensities of the superconducting phases. In addition, SEM images showed that Sb substitution decreases the grain size and modifies the microstructure development, which makes the samples denser.
  • Article
    Citation - WoS: 17
    Citation - Scopus: 19
    Effect of Compaction Pressure on Structural and Superconducting Properties of Bi-2223 Superconductors
    (Springer Verlag, 2010) Kocabaş, Kemal; Gökçe, Melis; Çiftçioğlu, Muhsin; Bilgili, Özlem
    In this work, effects of compaction pressure on the structural and superconducting properties of BSCCO ceramic superconductors were investigated. The study was carried out on two systems which were, System I: Bi 1.7Pb 0.3Sr 2Ca 2Cu 3O y and System II: Bi 1.6Pb 0.3Ag 0.1Sr 2Ca 2Cu 3O y, respectively. Ceramic powders were prepared by conventional solid-state reaction method and sintered at 850°C after compaction at five different pressures in the 150-750 MPa range. Critical temperatures of samples were determined by resistivity-temperature determinations made by four-point probe method in liquid nitrogen conditions. XRD analysis was conducted by powder X-ray diffraction method. Morphology of the grains present in the samples were determined by using scanning electron microscope (SEM) photographs at 2 K× and 2.5 K× magnifications for System I and System II, respectively. Sintered densities of the superconducting ceramics were measured by Archimedes water displacement method and unit cell parameters were additionally obtained from XRD data. T c values for System I was determined to be in the 109-115 K with sample D having the highest T c of 115 K while T c varied in the 104-109 K range and sample B had the highest T c value of 109 K for System II. The transition width, which is a sign of the purity of the samples, was determined to be narrow for both systems. The data obtained from X-ray diffraction measurements have shown that 2223 high-T c phase was dominant in both systems. The determination of the optimum pellet compaction pressure for BSCCO ceramic superconductors was the main purpose of this work. The results of this work indicated that compaction at around 450 MPa improves the superconducting and structural properties of the BSCCO ceramic superconductors. © 2009 Springer Science+Business Media, LLC.
  • Article
    Citation - WoS: 12
    Citation - Scopus: 12
    The Effect of Zn Substitution of Ca in Bipbsrcacuo Superconductors Sintered at 830°c
    (Springer Verlag, 2009) Kocabaş, Kemal; Şakiroğlu, Serpil; Çiftçioğlu, Muhsin; Ercan, İsmail; Epik, Hakan; Bilgili, Özlem
    The effect of partial substitution of Ca by Zn in Bi 1.7Pb 0.3Sr 2Ca 2-x Zn x Cu 3O y at x=0.00, 0.05, 0.10, 0.15 and 0.20 levels on the electrical and structural properties was investigated in this work. The characterization of the ceramics prepared by the conventional solid-state reaction method were done by resistance-temperature measurements, XRD, SEM and density analysis. Low levels of Zn substitution of Ca caused significant changes in the properties of the ceramics. The low-T c superconducting properties were enhanced and the fraction of the low-T c (2212) phase were found to increase at x=0.15 level of Zn substitution at 830°C sintering temperature. Zero resistance was observed only in sample D with x=0.15 and the T c was determined as 92 K. The SEM micrographs and the density analysis have shown that this was the densest packed ceramic.
  • Article
    Citation - WoS: 19
    Citation - Scopus: 21
    Microwave Effect on Ion-Exchange and Structure of Clinoptilolite
    (Springer Verlag, 2007) Akdeniz, Yelda; Ülkü, Semra
    The effect of microwave irradiation on the ion exchange degree and structure of clinoptilolite mineral has been examined in comparison with the conventional heat treatment in waterbath. Clinoptilolite-rich mineral from the Western Anatolia, Bigadiç region was used for the experimental study. The mineral was mainly clinoptilolite (80-85%) and additionally, quartz (5-10%), and analcime+mordenite (<5%) were found as co-existing minerals. The mineral was stable towards dehydration and maintains its original structure up to 800°C. The BET and Langmuir surface areas of the sample were found to be 22 and 17m2/g for N2 adsorption and 28 and 22m2/g for Ar adsorption, respectively. For the exchange experiments, clinoptilolite rich mineral was treated with 1N NaCl salt solution both in a microwave unit and waterbath for 10min, 1h and 2h at 80°C. The waterbath treatment with the same conditions was continued for two additional weeks. The chemical composition of the parent and Na-exchanged forms of the clinoptilolite rich minerals were analyzed by using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). Microwave treatment was found to be more rapid and effective for ion exchange compared to conventional waterbath treatment. Additionally, the XRD results reveal that microwave irradiation has zero effect on the structure of the clinoptilolite rich mineral.
  • Article
    Citation - WoS: 30
    Citation - Scopus: 35
    Effect of Temperature and Time on Zinc Borate Species Formed From Zinc Oxide and Boric Acid in Aqueous Medium
    (American Chemical Society, 2007) Eltepe, H. Emre; Balköse, Devrim; Ülkü, Semra
    The effect of temperature and time of heating of zinc oxide and boric acid in aqueous medium on product type, dehydration behavior, crystal morphology, and structure was investigated for the production of flame retardant and smoke suppressant zinc borate. Two different products dehydrated at 140 and 350°C were obtained and characterized by thermal gravimetric analysis, X-ray diffraction, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy.