PVP-AŞILANMIŞ NiFe2O4 NANO PARÇACIKLARININ YÜZEY POLİMERİZASYON TEKNİĞİ İLE SENTEZİ

Nikel ferrit nano parçacıkları, surfaktant destekli hidrotermal teknik kullanılarak, kontrollü parçacık boyutu ve boyut dağılımı ile sentezlenmiştir. Manyetik nano parçacıkların yüzey modifikasyonu (3-chloropropyl)triethoxysilane ile gerçekleştirilmiştir. Modifiye edilen nano parçacıklar yüzeyden başlatılan polimerizasyon tekniği kullanılarak PVP ile aşı polimer yapısında kaplanmıştır. Elde edilen spinel ferritlerin kristal yapısı ve boyutu X-Işını Kırınım Analizi (XRD) ve Taramalı Elektron Mikroskopu (SEM) ile araştırılmıştır. Nano parçacıkların ve nano kompozitlerin manyetik özellikleri Titreşimli Örnek Magnetometresi (VSM) kullanılarak incelenmiştir. Elde edilen NiFe2O4 nano parçacıklarının ortalama parçacık boyutu 24 nm’dir. Oda sıcaklığında süper paramagnetik karakter ve yüksek doygunluk manyetizasyonu göstermektedir. Gerçekleştirilen sentez stratejisinin biyo-uygulamalarda kullanılacak gelişmiş malzemelerin sentezinde etkili bir yöntem olabileceği düşünülmektedir

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

Preparation of spinel ferrite nanoparticles using the hydrothermal technique and investigation of magnetic properties

Kobalt, nikel ve çinko ferrit nano parçacıkları hidrotermal sentez yöntemi kullanılarak sentezlenmiştir. Sentez koşullarının elde edilen spinel ferritlerin kristal yapısı, parçacık boyutu, örgü parametreleri, mikroyapı ve manyetik özellikler üzerine etkileri XIşını Kırınım Analizi (XRD), taramalı elektron mikroskopu (SEM), Enerji-dağılımlı X-ışınları spektroskopisi (EDX) ve Mapping yöntemleriyle belirlenmiştir. Hazırlanan ferritlerin parçacık boyutu 25-70 nm arasında değişmektedir. Ayrıca, nano parçacıkların manyetik özellikleri titreşimli örnek magnetometresi (VSM) kullanılarak araştırılmıştır. Manyetik özelliklerin sıcaklık ve Co, Ni ve Çinko iyon çeşidine şiddetle bağımlı olduğu gözlenmiştir. Bu örnekler yüksek yoğunluklu manyetik kayıtlama cihazlarında, yüksek kullanım potansiyeline sahiptir.Cobalt, nickel and zinc ferrites nanoparticles have been synthesized using the hydrothermally technique. Effects of synthesis conditions on the crystal structure, crystallite size, lattice parameter, microstructure and magnetic properties of the produced spinel ferrites were investigated by X-ray diffraction analysis (XRD), scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy (EDX) and Mapping techniques. The mean crystallite size of the prepared ferrite was in the range of 25-70 nm. Furthermore, the magnetic properties of nanoparticles were investigated using a vibrating sample magnetometer (VSM). Strong temperature and Co, Ni, and Zn ions dependence of magnetic properties was observed. These samples are considered as promising materials for high density magnetic recording media

Synthesis and characterization of polyimides prepared from optically active (R,R) and (S,S)-1,3-bis (p-N,N'- dimethylaminobenzyl)-perhydrobenzimidazol-2-thion

This paper presents the synthesis and characterization of polyimides containing a chiral (R,R)or (S,S) 1,3-bis(p-N,N'-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion unit in the backbone.The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p -N,N'-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material.This paper presents the synthesis and characterization of polyimides containing a chiral (R,R)or (S,S) 1,3-bis(p-N,N'-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion unit in the backbone.The reactions occur between equimolar amounts of a dianhydride and an aromatic dimethylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis(p -N,N'-dimethylaminobenzyl)-perhydrobenzimidazol-2-thion were used as diamines. The polyimides obtained were characterized by thermogravimetry (TGA), differential thermal analysis (DTA), differential scanning calorimeter (DSC), infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material

SPİNEL FERRİT NANO-PARÇACIKLARININ HİDROTERMAL SENTEZ TEKNİĞİ KULLANILARAK HAZIRLANMASI ve MANYETİK ÖZELLİKLERİNİN ARAŞTIRILMASI

Kobalt, nikel ve çinko ferrit nano parçacıkları hidrotermal sentez yöntemi kullanılarak sentezlenmiştir. Sentez koşullarının elde edilen spinel ferritlerin kristal yapısı, parçacık boyutu, örgü parametreleri, mikroyapı ve manyetik özellikler üzerine etkileri X-Işını Kırınım Analizi (XRD), taramalı elektron mikroskopu (SEM), Enerji-dağılımlı X-ışınları spektroskopisi (EDX) ve Mapping yöntemleriyle belirlenmiştir. Hazırlanan ferritlerin parçacık boyutu 25-70 nm arasında değişmektedir. Ayrıca, nano parçacıkların manyetik özellikleri titreşimli örnek magnetometresi (VSM) kullanılarak araştırılmıştır. Manyetik özelliklerin sıcaklık ve iyon çeşidine bağlı olarak değiştiği gözlenmiştir. Elde edilen manyetik özelliklere göre hazırlanan örnekler yüksek yoğunluklu manyetik kayıtlama cihazlarında, yüksek kullanım potansiyeline sahiptir

The Toxicity Assessment of Iron Oxide (Fe3O4) Nanoparticles on Physical and Biochemical Quality of Rainbow Trout Spermatozoon

The aim of this study was to evaluate the in vitro effect of different doses (50, 100, 200, 400, and 800 mg/L) of Fe3O4 nanoparticles (NPs) at 4 °C for 24 h on the kinematics of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) spermatozoon. Firstly, Fe3O4 NPs were prepared at about 30 nm from Iron (III) chloride, Iron (II) chloride, and NH3 via a co-precipitation synthesis technique. Then, the prepared Fe3O4 NPs were characterized by different instrumental techniques for their chemical structure, purity, morphology, surface properties, and thermal behavior. The size, microstructure, and morphology of the prepared Fe3O4 NPs were studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) spectroscopy, and scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS). The thermal properties of the Fe3O4 NPs were determined with thermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimeter (DSC) analysis techniques. According to our results, there were statistically significant (p < 0.05) decreases in the velocities of spermatozoon after treatment with 400 mg/L Fe3O4 NPs. The superoxide dismutase (SOD) and catalase (CAT) activities were significant (p < 0.05) decrease after 100 mg/L in after exposure to Fe3O4 NPs in 24 h. As the doses of Fe3O4 NPs increases, the level of malondialdehyde (MDA) and total glutathione (tGSH) significantly (p < 0.05) increased at doses of 400 and 800 mg/L

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 asinvestigated structural parameters and morphology of the ZnO structure were affected directly by the concentrationof Y dopant. For each Y-doped sample, randomly-oriented pyramidal morphology and the formation of a minorityphase of Y2O3 were observed. A gradual increase in both lattice parameters and unit cell volume was detected withincreasing Y content. All samples were found to be thermally stable in the temperature interval of 25-950 °C

Aliphatic Polyurethane Films Based on Hexamethylene Diisocyanate and Saccharides for Biocompatible Transparent Coating on Optic Medical Devices

Polyurethanes are widely used in daily life, from the textile industry to medical applications. In this study, a biocompatible and transparent coating from polyethylene glycol-based polyurethanes including different type of saccharide (xylose as monosaccharide, sucrose as disaccharide, or starch as polysaccharide) is prepared. Prepared optically transparent polyurethanes are characterized with different instrumental analysis techniques and contact-angle measurements. Thermogravimetric analysis data allow understanding that the synthesized saccharide based polyurethanes are resistant to high temperatures, which means that medical devices can be easily coated with one of the saccharide-based polymers during the manufacturing process. The study results also show that synthesized polyurethane samples having a different kind of saccharides present high biocompatibility and transparency properties via In vitro cytotoxicity analysis and optic transparency tests. For xylose, sucrose, or starch containing polyurethanes, the tranmittance values are 97.72%, 85.20%, and 89.23%, respectively. In addition, scanning electron microscope images show that the samples also have smooth surfaces which can be used for proper coating of medical devices. Consequently, this manuscript addresses synthesis and characterization of the optically transparent polyurethanes based on specific saccharides for biocompatible and transparent surfaces especially in optic medical devices such as colonoscopy applications and laparoscopic detection probes.Scientific and Technical Research Council of Turkey (TUBTAK) [111T104]This study was supported by a grant (111T104) to Burhan ATES from The Scientific and Technical Research Council of Turkey (TUBTAK)