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Articles 1 - 16 of 16
Full-Text Articles in Physical Sciences and Mathematics
Fabrication Of Electrospun Cellulose-Derived Nanofiber Membranes With Enhanced Stability Properties Of Arginase, Ceyhun Işik, Mustafa Teke
Fabrication Of Electrospun Cellulose-Derived Nanofiber Membranes With Enhanced Stability Properties Of Arginase, Ceyhun Işik, Mustafa Teke
Turkish Journal of Chemistry
In this study, cellulose acetate (CA)/polyvinylpyrrolidone (PVP) and CA/PVP/Mn2+ nanofibers were produced by the electrospinning method, and these cellulose-derived membranes were used as carriers for arginase immobilization for the first time. The structural and morphological analysis of these cellulose-derived nanofibers were determined by attenuated total reflection-Fourier to transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). After the immobilization process, it was observed that the thermal properties of the cellulose-derived nanofibers especially improved. The optimum temperature value for free arginase was found to be 35 °C, and this value was found to be 40 …
Cyclotide-Rich Fractions Containing Nanofibers By Electrospinning: Preparation, Characterization And Examination Of Antimicrobial Activity, Eli̇f Büşra Baş, Cemi̇l Kürekci̇, Orhan Murat Kalfa, Muharrem Akcan
Cyclotide-Rich Fractions Containing Nanofibers By Electrospinning: Preparation, Characterization And Examination Of Antimicrobial Activity, Eli̇f Büşra Baş, Cemi̇l Kürekci̇, Orhan Murat Kalfa, Muharrem Akcan
Turkish Journal of Chemistry
In this study, antimicrobial nanofibers were produced with the mixtures of polyvinyl alcohol (PVA) and cyclotide-rich fractions by electrospinning method. After extraction, the first separation was carried out with C18 flash chromatography and then fractioned into five separate parts by reversed-phase high-pressure liquid chromatography (RP-HPLC). The molecular weights of cyclotides in each fraction were determined by quadrupole time-of-flight liquid chromatography-mass spectrometry (Q-TOF LC-MS). Cyclotide-rich fractions were mixed with 10% of PVA solution and nanofibers were produced from this biocomposite mixture by electrospinning method. The nanofibers were characterized by field emission scanning electron microscopy (FE-SEM), and it was observed that 100% …
Ytterbium Oxide Nanofibers: Fabrication And Characterization For Energy Applications, Adem Sarilmaz
Ytterbium Oxide Nanofibers: Fabrication And Characterization For Energy Applications, Adem Sarilmaz
Turkish Journal of Chemistry
Metal oxide nanomaterials are widely used in many applications of renewable energy. Ytterbium oxide (Yb2O3) also attracts attention due to its similar structure to ZnO (~3,26 eV) and TiO2 (~3,36 eV) in terms of bandgap energy. In this study, Yb2O3 belonging to the lanthanide oxide family was produced as nanofiber forms by using the electrospinning technique, which allows for large-scale production, for the first time. The morphological, structural, optical, and phase properties of the produced nanofibers were investigated via XRD, SEM-Mapping, TEM, FTIR, UV-Vis, and XPS characterization techniques. As a result of …
Removal Of Polycyclic Aromatic Hydrocarbons (Pahs) From Water Through Degradable Polycaprolactone Electrospun Membrane, Fuat Topuz
Turkish Journal of Chemistry
Polycyclic aromatic hydrocarbons (PAHs) are common and persistent environmental pollutants produced during the incomplete combustion of fuels. They are known for their carcinogenic and mutagenic properties. Thus, their removal from water bodies is highly crucial and has become a critical issue globally. As a solution, here an electrospun polycaprolactone (PCL) membrane with a mean fiber diameter of 2.74 ± 1.3 μm was produced by electrospinning. Water contact angle (WCA) analysis confirmed the hydrophobic nature of the PCL membrane with a WCA of 124°, which remained stable over time. Differential scanning calorimetry analysis (DSC) revealed the semicrystalline nature of the membrane …
In-Situ Synthesis Of Phthalocyanines On Electrospun Tio2 Nanofiber By Solvothermal Process For Photocatalytic Degradation Of Methylene Blue, Seli̇n Gümrükçü, Mukaddes Özçeşmeci̇, Esma Sezer, Belkiz Ustamehmetoğlu, Esi̇n Hamuryudan
In-Situ Synthesis Of Phthalocyanines On Electrospun Tio2 Nanofiber By Solvothermal Process For Photocatalytic Degradation Of Methylene Blue, Seli̇n Gümrükçü, Mukaddes Özçeşmeci̇, Esma Sezer, Belkiz Ustamehmetoğlu, Esi̇n Hamuryudan
Turkish Journal of Chemistry
Titanium dioxide/phthalocyanine (TiO2/Pc), TiO2/fluor containing phthalocyanine (TiO2/FPc), and TiO2/fluor containing cobalt phthalocyanine (TiO2/FCoPc) had been successfully fabricated by a simple combination of phthalocyanines obtained by in-situ synthesis on the surface of TiO2 nanofibers prepared by electrospinning. Scanning electron microscopy micrographs and X-ray diffraction analysis indicated that the phthalocyanines uniformly immobilized on the surface of TiO2 nanofibers. Photocatalytic activity of TiO2, TiO2/Pc, TiO2/FPc, TiO2/FCoPc nanofibers for methylene blue in water was comparatively investigated firstly by ultraviolet-visible absorption measurements with time, and kinetic parameters were calculated. Results indicated that the obtained TiO2/Pc, TiO2/FPc and TiO2/FCoPc exhibited high photocatalytic activity for the degradation …
Evaluation Of The Fuel Cell Performances Of Tio2/Pan Electrospun Carbon-Based Electrodes, Sema Aslan
Evaluation Of The Fuel Cell Performances Of Tio2/Pan Electrospun Carbon-Based Electrodes, Sema Aslan
Turkish Journal of Chemistry
Electrocatalytic effect of the untreated and TiO2+polyacrylonitrile (PAN) modified discarded battery coal (DBC) and pencil graphite electrodes (PGE) were evaluated in fuel cell (FC) applications. TiO2+PAN solution is coated on PGE and DBC electrodes by electrospinning. According to the FESEM and EDS characterizations, TiO2 and PAN nanofibers are found to be approximately 40 and 240 nm in size. TiO2+PAN/PGE showed the best FC performances with 2.00 A cm-2 current density and 5.05 W cm-2 power density values, whereas TiO2+PAN/DBC showed 0.68 A cm-2 current density and 0.62 W cm-2 power density values. Electrochemical characterizations of PGE and TiO2+PAN/PGE electrodes were …
Pan-Based Activated Carbon Nanofiber/Metal Oxide Composites For Co2 And Ch4adsorption: Influence Of Metal Oxide, Çi̇sem Kirbiyik Kurukavak, Burak Zafer Büyükbekar, Mustafa Ersöz
Pan-Based Activated Carbon Nanofiber/Metal Oxide Composites For Co2 And Ch4adsorption: Influence Of Metal Oxide, Çi̇sem Kirbiyik Kurukavak, Burak Zafer Büyükbekar, Mustafa Ersöz
Turkish Journal of Chemistry
In the present study, we successfully prepared two different electrospun polyacrylonitrile (PAN) based-activated carbon nanofiber (ACNF) composites by incorporation of well-distributed Fe2O3 and Co3O4 nanoparticles (NPs). The influence of metal oxide on the structural, morphological, and textural properties of final composites was thoroughly investigated. The results showed that the morphological and textural properties could be easily tuned by changing the metal oxide NPs. Even though, the ACNF composites were not chemically activated by any activation agent, they presented relatively high surface areas (SBET) calculated by Brunauer?Emmett? Teller (BET) equation as 212.21 and 185.12 m2/g for ACNF/Fe2O3 and ACNF/Co3O4 composites, respectively. …
Silk Fiber-Based Composite Nanofiber Tissue Scaffold Produced With Electrospinning Method, Meti̇n Yüksek, Mehmet Akalin, Erhan Sancak, Erkan İşgören, Onur Atak, Derya Saltik Çi̇rki̇n, Ali̇ Beyi̇t
Silk Fiber-Based Composite Nanofiber Tissue Scaffold Produced With Electrospinning Method, Meti̇n Yüksek, Mehmet Akalin, Erhan Sancak, Erkan İşgören, Onur Atak, Derya Saltik Çi̇rki̇n, Ali̇ Beyi̇t
Turkish Journal of Chemistry
Wound dressings are one of the most rapidly expanding areas in medical textiles. In recent years, a large number of functional wound dressing has been developed. The aims of these products are to speed up the wound healing process and to provide maximum comfort for patients. Today, the multidisciplinary studies are required to improve further existed wound dressings. The results of such research studies are also promised new hopes for the Turkish textile industry weakened by the global competition. For this purpose, three different polymers were selected as silk fibroin (SF) / polycaprolactone (PCL) / polyethylene oxide (PEO). The productions …
Characterization, Mechanical, And Antibacterial Properties Of Nanofibers Derived From Olive Leaf, Fumitory, And Terebinth Extracts, Ni̇lşen Sünter Eroğlu, Suat Canoğlu, Meti̇n Yüksek
Characterization, Mechanical, And Antibacterial Properties Of Nanofibers Derived From Olive Leaf, Fumitory, And Terebinth Extracts, Ni̇lşen Sünter Eroğlu, Suat Canoğlu, Meti̇n Yüksek
Turkish Journal of Chemistry
In this study, nanofiber structures were obtained with convenient polymers (PVA [polyvinyl alcohol] and PCL [poly º-caprolactone]) derived from the herbal extracts of olive leaves, fumitory, and terebinth plants. Optimum nanofiber structures were identified by measuring viscosity and conductivity values and performing morphological analysis, characterization, and mechanical tests of the prepared solutions. The potential use for wound healing at the most efficient level was determined as a result of antibacterial analysis of the structures obtained. APT (PVA/terebinth) and BFO (PCL/fumitory) nanofibers had the thinnest diameter range and the highest strength values. In terms of the determination of antibacterial effects, nanofiber …
Effect Of Cnt Incorporation On Pan/Ppy Nanofibers Synthesized By Electrospinning Method, Ati̇ke İnce Yardimci, Meti̇n Tanoğlu, Selahatti̇n Yilmaz, Yusuf Selamet
Effect Of Cnt Incorporation On Pan/Ppy Nanofibers Synthesized By Electrospinning Method, Ati̇ke İnce Yardimci, Meti̇n Tanoğlu, Selahatti̇n Yilmaz, Yusuf Selamet
Turkish Journal of Chemistry
In this study, carbon nanotubes (CNTs) added polyacrylonitrile/polypyrrole (PAN/PPy) electrospun nanofibers were produced. Average diameters of the nanofibers were measured as 268 and 153 nm for 10 and 25 wt% of PPy contents, respectively. A relatively higher strain to failure values (23.3%) were observed for the low PPy content. When as-grown CNTs (1 and 4 wt%) were added into the PAN/PPy blends, disordered nanofibers were observed to form within the microstructure. To improve the interfacial properties of CNTs/PAN/PPy composites, CNTs were functionalized with H$_{2}$SO$_{4}$/HNO$_{3}$/HCl solution. The functionalized CNTs were well dispersed within the nanofibers and aligned along the direction of …
Effect Of Polyvinyl Alcohol/Chitosan Blend Ratios On Morphological, Optical, And Thermal Properties Of Electrospun Nanofibers, Gökhan Açik, Musa Kamaci, Burak Özata, Cahi̇de Eli̇f Özen Cansoy
Effect Of Polyvinyl Alcohol/Chitosan Blend Ratios On Morphological, Optical, And Thermal Properties Of Electrospun Nanofibers, Gökhan Açik, Musa Kamaci, Burak Özata, Cahi̇de Eli̇f Özen Cansoy
Turkish Journal of Chemistry
In this study, the electrospinning method was used to prepare polyvinyl alcohol (PVA)/chitosan (CS) blend nanofibers from their solutions. The effect of blend ratios (PVA/CS: 1%, 3%, 5%, and 7% (w/w)), applied voltage, and flow rate on the morphological, optical, and thermal properties of electrospun nanofibers were investigated by scanning electron microscopy (SEM), fluorescence and UV-Vis spectroscopies, and thermogravimetric analysis (TGA), respectively. Fourier transform infrared spectroscopy analysis indicated the existence of related functional groups of both PVA and CS in the electrospun fibers. During the electrospinning process, the maximum possible ratio of CS was 7% (w/w). SEM images indicated that …
Development Of A Nanoscale-Based Optical Chemical Sensor For The Detection Of No Radical, Özlem Öter, Aki̇f Ci̇han Aydin, Merve Zeyrek Ongun, Erdal Çeli̇k
Development Of A Nanoscale-Based Optical Chemical Sensor For The Detection Of No Radical, Özlem Öter, Aki̇f Ci̇han Aydin, Merve Zeyrek Ongun, Erdal Çeli̇k
Turkish Journal of Chemistry
Nitric oxide is one of the most important biochemical parameters in biological processes; it is also known as carcinogenic. There is need for the design of stable and durable solid phase nitric oxide sensors. In this study, we immobilized the nitric oxide sensitive molecules pyrene, tris(2,2'-bipyrdyl)dichlororuthenium(II) hexahydrate (Ru(bipy)$_{3}^{2+})$, and magnesium phthalocyanine (Mg-Pc) for the first time in polymeric or glassy matrices. We applied silver nanoparticles and ionic liquids in the fabrication process of polymeric electrospun fibers and thin films. We compared their NO sensitivity in micelle solutions that mimic the cell medium by both steady state and lifetime-based fluorescence measurements. …
Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh
Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh
Turkish Journal of Chemistry
Superhydrophobic nanocomposite coatings for magnesium surfaces with remarkable corrosion resistance were fabricated by electrospinning in the presence of fluorosilane-functionalized silica (SiO$_{2})$ nanoparticles. The effects of surface-modified silica (mod-SiO$_{2})$ nanoparticles on the superhydrophobicity and corrosion resistance of polystyrene (PS)/mod-SiO$_{2}$ fiber coatings were evaluated. The incorporation of the SiO$_{2}$ nanoparticles endows PS fibers with rough surfaces exhibiting a water contact angle (WCA) of 165$^{\circ}$. The surface wettability, corrosion resistance, and their relation to the inorganic content in the PS fibers and the contact angle of the composite coatings were explored. Analysis of the corrosion results confirmed that the PS/mod-SiO$_{2}$ coating protected the …
Gaseous And Dissolved Oxygen Sensing With Stabilized Pyrene In Ionic Liquid Modified Electrospun Slides, Özlem Öter, Gülhan Sabanci Şahi̇n
Gaseous And Dissolved Oxygen Sensing With Stabilized Pyrene In Ionic Liquid Modified Electrospun Slides, Özlem Öter, Gülhan Sabanci Şahi̇n
Turkish Journal of Chemistry
Pyrene dye has many superior characteristics for oxygen sensing studies such as long fluorescence lifetime, high quantum yield, and good sensitivity. It is preferred in some cases over ruthenium dyes for its more lipophilic character and higher sensitivity. However, easy photodegradation of pyrene is a challenging problem. In this study, pyrene dye was for the first time immobilized in an ethyl cellulose matrix and used for oxygen sensing in the form of thin films and electrospun sensing slides. The hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was used as additive for the first time for dissolved oxygen sensing studies. The oxygen sensitivity …
A Comparative Study On Fabrication Of Cu$_{2}$Znsns$_{4}$ (Czts) Nanofibers Using Acetate And Chloride Metal Precursors, Burak Zafer Büyükbekar, Faruk Özel, Hüseyi̇n Şakalak, Hali̇t Çavuşoğlu, Mustafa Ersöz, Mahmut Kuş, Mustafa Selman Yavuz
A Comparative Study On Fabrication Of Cu$_{2}$Znsns$_{4}$ (Czts) Nanofibers Using Acetate And Chloride Metal Precursors, Burak Zafer Büyükbekar, Faruk Özel, Hüseyi̇n Şakalak, Hali̇t Çavuşoğlu, Mustafa Ersöz, Mahmut Kuş, Mustafa Selman Yavuz
Turkish Journal of Chemistry
This study reports, for the first time, the fabrication of electrospun Cu$_{2}$ZnSnS$_{4}$ (CZTS) nanofibers using metal acetate precursors. Viscous poly(vinyl pyrrolidone) (PVP) solution containing acetate or chloride salts of copper, zinc, and tin was electrospun onto a conductive substrate. The PVP nanofibers that have a mixture of metal salts were annealed at elevated temperatures. After calcination, these nanofibers were treated with the sulfur source and then annealed again in order to generate CZTS nanofibers. The CZTS nanofibers generated from acetate and chloride salts were characterized and compared. Belt-like and wire-like nanofibers were obtained when using metal acetate and chloride precursors, …
Preparation Of Porphyrinated Polyacrylonitrile Fiber Mat Supported Tio_2 Photocatalyst And Its Photocatalytic Activities, Linjun Shao, Ji Chen, Luyao He, Guiying Xing, Weixi Lv, Zaina Chen, Chenze Qi
Preparation Of Porphyrinated Polyacrylonitrile Fiber Mat Supported Tio_2 Photocatalyst And Its Photocatalytic Activities, Linjun Shao, Ji Chen, Luyao He, Guiying Xing, Weixi Lv, Zaina Chen, Chenze Qi
Turkish Journal of Chemistry
Fe(III)meso-tetraphenylporphyrinated polyacrylonitrile fiber mat supported TiO_2 photocatalyst (PANC/ TiO_2 mat) was prepared via copolymerization and electrospinning. SEM images showed that well-defined fibers with diameters around 1.47 \pm 0.26 \mu m were fabricated from Fe(III)meso-tetraphenylporphyrin (FeTPP)-acrylonitrile copolymer (PANC) and TiO_2 mixture. The XRD characterizations demonstrated that the electrospinning process had no effect on the anatase structure of TiO_2. The photocatalytic activity of the PANC/TiO_2 mat was examined for the photodegradation of methyl red in aqueous solution under the irradiation of visible light. The results showed that this PANC/TiO_2 fiber mat was very efficient for the photodegradation of methyl red, with a …