Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Aydin, Handan(2)
- Demirelli, Kadir(2)
- Gündüz, Bayram(2)
- ALMisned, Ghada(1)
- Adigüzel, Ragip(1)
- Al-Ghamdif, Ahmed A.(1)
- Al-Sehemi, Abdullah G.(1)
- Aslan, Naim(1)
- Aydin, Cihat(1)
- Aydın, Handan(1)
- Barim, Esra(1)
- Barım, Esra(1)
- Başman, Necati(1)
- Birdogan, Selcuk(1)
- Buldurun, Kenan(1)
- Canbay, Canan Aksu(1)
- Dere, Ayşegül(1)
- Durmus, Hasan(1)
- Erkovan, Mustafa(1)
- Guler, Seval Hale(1)
- Güler, Ömer(1)
- Ilik, E.(1)
- Karaduman, Oktay(1)
- Kavaz, E.(1)
- Kilic, G.(1)
- Körkoca, Hanifi(1)
- Tekin, H.O.(1)
- Torgut, Gülben(1)
- Tuncer, Hülya(1)
- Turan, Nevin(1)
- Uzun, Orhan(1)
- Yakuphanoğlu, Fahretttin(1)
- Yakuphanoǧlu, Fahrettin(1)
- Çolak, Naki(1)
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ1Preparation of Nanographene-Based Copolymer Nanocomposites: Thermal Decomposition Kinetic, Optical, and Electrical Behaviors
Barim, Esra; Demirelli, Kadir
The poly(4-methacryloyloxyphenyl-4'-methoxystyryl ketone-co-methyl methacrylate) [P(MPMESK0.25-co-MMA)] was synthesized using a free radical copolymerization method at 60 °C. The composition of the copolymer was estimated by 1H-NMR. The nanocomposites of P(MPMESK0.25-co-MMA)-loaded 9 and 11 wt% nanographene (NG) were produced using the ultrasonic homogenizer sonicator. The FT-IR, 1H-NMR, GPC, TGA, XRD, and SEM techniques were used to characterize the copolymer and composites. The thermal behavior of P(MPMESK0.25-co-MMA) partially heated up to 270, 310, 340, and 380 °C was investigated by FT-IR analysis. A six-membered anhydride ring in the copolymer backbone formed at 340 °C and higher temperatures. TG measurements were used to analyze the thermal decomposition processes of pure P(MPMESK0.25-co-MMA) and P(MPMESK0.25-co-MMA)/NG 11 wt% composite. Apparent activation energies for thermal decomposition of P(MPMESK0.25-co-MMA)/NG 11 wt% were determined using the Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) methods at a temperature range of 200 and 400 °C for a weight loss of approximately 70%. The average activation energies determined from the FWO and KAS methods were 86.3 and 80.3 kJ/mol, respectively. The dielectric and electrical behaviors of the P(MPMESK0.25-co-MMA) and P(MPMESK0.25-co-MMA)/NG 11 wt% composite were investigated at room temperature. The dc activation energy for dc conductivity of nanocomposite was calculated as 1.092 eV. Optical properties such as absorption, reflectance, refractive index, absorption edge, direct band gap of the copolymer, and composites were investigated from their optical examinations in the wavelength region of 200–800 nm. It was found that the optical energy gap values had shifted to the lower energies with the doping of NG.
AtıfScopus1OpenAlex1
İncele - MakaleYalnız künye2025Scopus SJRQ1Impact of controlled oxidation and incorporation of high entropy rare-earth alloys (HE-REAs) on the structural, physical, optical, and radiation shielding performance of zinc-borate glasses
Ilik, E.; Guler, Seval Hale; Güler, Ömer; Durmus, Hasan; Kavaz, E.; Birdogan, Selcuk; ALMisned, Ghada; Kilic, G.; Tekin, H.O.
This study investigates the influence of high entropy oxide (HEO) and high entropy alloy oxide (HEAO) dopants on the structural, optical, and radiation shielding properties of zinc-borate glasses. Two synthesis routes were employed through direct mechanical alloying of five rare-earth oxides such as Sm2O3, Ho2O3, Er2O3, Yb2O3, Gd2O3 to form (SmHoErYbGd)2O3 HEO, and mechanical alloying of the corresponding rare-earth metals followed by oxidation to produce HEAO of the same elemental composition. The central hypothesis proposed that the dopant structure and oxygen coordination, not just elemental presence, critically influence the on characteristic behaviors in terms of radiation attenuation. Structural analyses confirmed that HEAO-doped glasses exhibit more homogeneous, amorphous networks. Optical characterizations revealed red-shifted absorption edges and lower Urbach energies in HEAO samples, indicating reduced disorder. HEAO-doped glasses showed superior gamma-ray shielding, with higher linear attenuation coefficients and lower half-value layers than HEO or undoped samples. Most notably, HEAO glass achieved the highest fast neutron removal cross-section, surpassing water, graphite, and B4C. These findings demonstrate that rare-earth high entropy alloy oxides offer a structurally optimized pathway for designing next-generation multifunctional glasses for radiation-related applications.
AtıfScopus9OpenAlex8
İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2Controlling of electro-optical properties of cobalt phthalocyanine formed single chain polymer: Sudan III and nanographene based its composites
Demirelli, Kadir; Barım, Esra; Tuncer, Hülya; Dere, Ayşegül; Canbay, Canan Aksu; Karaduman, Oktay; Al-Sehemi, Abdullah G.; Al-Ghamdif, Ahmed A.; Yakuphanoğlu, Fahretttin
The synthesis of poly[4-(4-vinylbenzyl)oxy)phthalonitrile-co-styrene] [P(VBOPN5 %-co-St)] was carried out by free radical polymerisation at 60 °C. The successful formation of a green coloured single-chain polymer molecule with the formation of cobalt phthalocyanine (SCP-CoPc) was performed at 140–150 °C in the presence of dilute cyclohexanol. The characterization of SCP-CoPc was confirmed by FT-IR and UV/vis spectroscopic techniques. The absorption filtration process of the SCP-CoPc polymer/Sudan III composite was investigated. The introduction of Sudan III into the SCP-CoPc polymer matric strongly affected the optical transmission spectrum of the composite films. The optical transmission measurements of the SCP-CoPc/Sudan III thin film show a high absorption in the visible region (400–800 nm). In the SCP-CoPc/Sudan III composites, the optical band gaps (Eg1 and Eg2) of each of its components has changed significantly. The Eg1 and Eg2 were found to be between 1.90 and 2.83 eV, respectively. Depending on the sudan III content, a wide range from 600 nm to 730 nm indicates complete absorption filtration. The dc electrical conductivity and dielectric behavior of the SCP-CoPc/Nanografene (NG) 6 wt% nanocomposite increased with increasing temperature. From the dc conductivity plot, the Ea values of I. and II. regions were found to be 0.75 eV and 0.27 eV, respectively and it was found that the calculated activation energy obeyed the Arrhenius relationship. The refractive index and the optical permittivity of SCP-CoPc/NG 6 wt% have been estimated.
AtıfScopus2OpenAlex3İncele - MakaleYalnız künye2024Scopus SJRQ2Synthesis, spectroscopic characterization and optical studies of poly(AN-co-St) composites with doped lanthanum (III) chloride for aerospace applications
Aydin, Handan; Torgut, Gülben
In this study, firstly, the copolymer of acrylonitrile (AN) and styrene (St) was synthesized by solution polymerization method using 2,2′-azobisisobutyronitrile (AIBN) as an initiator. The composites of copolymer incorporating lanthanum (III) chloride (3, 6, 9 and 18 wt%), the rare earth element (REE), were prepared and thin films were produced by thermal evaporation method for optical measurement. The samples were characterized by attenuated total reflectance Fourier transform infrared (ATR–FTIR), scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS) and X-ray diffraction (XRD). The glass transition temperature, which is one of the thermal properties of the synthesized copolymers and composites, was examined with a differential thermal analyzer. The changes in the optical properties of the samples produced with LaCl3 dopant were investigated using the UV–VIS spectroscopy. The optical band gaps of the samples were calculated using Tauc equation. As a result of the optical studies, it was observed that there was a change in the conductivity properties of the samples with the addition of LaCl3. The present results showed the advantage of using LaCl3 as a filler to improve the optical properties of poly(AN-co-St) samples.
- MakaleYalnız künye2024Scopus SJRQ2Synthesis and characterization of MgO-doped PHA bio-composites
Aydın, Handan
In this study, a highly useable MgO doped polymer composite of Polyhydroxyalkanoates (PHA), which is an alternative to conventional plastics and an environmentally friendly plastic material due to its biodegradability, was investigated. PHA-MgO composites were obtained by stirring in a suitable solution for a long time with the help of a homogenizer. Then, MgO was added and the changes in Poly Hydroxy Alkonate (PHA) polymer composites were investigated according to the changing MgO ratio. Composites were prepared by adding MgO at different ratios of 1 %, 5 %, 10 % and 15 % into PHA. The structural results of the prepared samples were investigated by using XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscopy). In addition, the thermal properties of the composites were investigated by DSC (Differential Scanning Calorimetry) and TGA (Thermogravimetric Analysis). Furthermore, the optical properties of PHA-MgO composites were determined by UV-VIS spectrometry. Finally, since PHA polymer exhibits shape memory properties, the shape memory properties of the composites were also investigated.
AtıfScopus2WoS2OpenAlex3İncele - MakaleAçık Erişim2019Scopus SJRQ3The effects of deposition potential on the optical, morphological and mechanical properties of DLC films produced by electrochemical deposition technique at low voltages
Aslan, Naim; Başman, Necati; Uzun, Orhan; Erkovan, Mustafa; Yakuphanoǧlu, Fahrettin
Diamond-like carbon (DLC) films were electrochemically deposited onto indium tin oxide (ITO) substrates using acetic acid and deionized water as electrolyte at low deposition voltages (2.4 V and 60 V). The transmittance of the films was investigated by UV spectrometry. Transmittance measurements versus wavelength revealed that the films transmit 86 % to 89 % light in visible region and band gap of the films varies between 3.87 eV and 3.89 eV. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used for structural characterization to evaluate surface morphology of the DLC films. The grain size and the surface roughness increased for the films prepared at higher deposition potential, while their measured average height decreased. The mechanical properties (hardness H and elastic modulus Er) were determined from load-displacement curves which were obtained by using nanoindentation method. Hardness and elastic modulus of the films increased as the deposition voltage of the films increased from 2.4 V to 60 V.
AtıfScopus9OpenAlex4İncele - MakaleAçık Erişim2019Scopus SJRQ1Surface morphology, spectroscopy, optical and conductivity properties of transparent poly(9-vinylcarbazole) thin films modified with graphene oxide
Aydin, Handan; Gündüz, Bayram; Aydin, Cihat
In this work, we synthesized the graphene oxide by Hummers method and prepared poly-N-vinylcarbazole (PVK)/graphene oxide (GO) nanocomposites. We investigated the SEM images, FTIR and UV spectroscopy and ac conductivity properties of PVK:wt% (0, 1, 5, 10, 15%) GO nanocomposites thin films. The PVK and PVK/GO nanocomposites are dominant in near ultraviolet region. The absorption band edge of the films of the PVK/GO nanocomposites varies from 3.077 to 3.175 eV, while the allowed optical band gap of the 0, 1, 5, 10 and 15% wt. GO + PVK nanocomposites varies from 2.97 to 3.30 eV. The optical band gap and refractive indices of the PVK can be changed with increasing the percentage by weight of graphene oxide. The single oscillator energy varies from 3.358 to 3.670 eV, while the dispersion energy varies from 6.404 to 6.970 eV. The graphene oxide has an important effect on the ac conductivity of the PVK. Obtained results show that the PVK material modified with graphene oxide is promising for electronic, optical and optoelectronic technology.
AtıfScopus20WoS20OpenAlex22İncele - MakaleYalnız künye2014Scopus SJRQ3Study of Structure and Spectral Characteristics of the Zinc(II) and Copper(II) Complexes With 5,5-Dimethyl-2-(2-(3-nitrophenyl) hydrazono)cyclohexane-1,3-dione and Their Effects on Optical Properties and the Developing of the Energy Band Gap and Investigation of Antibacterial Activity
Turan, Nevin; Gündüz, Bayram; Körkoca, Hanifi; Adigüzel, Ragip; Çolak, Naki; Buldurun, Kenan
A new chelating ligand, 5,5-dimethyl-2-(2-(3-nitrophenyl)hydrazono)cyclohexane-1,3-dione (L), and four transition metal complexes were synthesized. The ligand and its complexes were characterized by IR, H-1 and C-13-NMR spectra, elemental analyses, magnetic susceptibility, mass spectra, UV-Vis. and thermogravimetry-differential thermal analysis (TGA-DTA). The metal complexes showed different geometric structures. Antibacterial tests of the ligand and complexes were also done. The Zn(II) complexes showed antibacterial activity against Staphylococcus aureus ATCC-25923 at middle level. The optical properties of the ligand and its complexes were extensively investigated by optical measurements. The average transmittance value of the ligand was the highest value, while the average transmittance value of the [CuL2(NO3)(2)]center dot 6H(2)O complex was the lowest value. The optical band gap of the ligand, [(Zn)(2)L(OH)(4)]center dot 2DMF, [ZnL(NO3)(2)(H2O)(2)]center dot 5H(2)O, [CuL2(OAc)]center dot OAc center dot 3.5H(2)O and [CuL2(NO3)(2)]center dot 6H(2)O complexes were calculated and 3.121 eV, 2.180 eV, 1.551 eV, 2.489 eV and 1.556 eV values were found, respectively. The complexes decreased the optical band gap of the ligand. The optical band gap value of the [ZnL(NO3)(2)(H2O)(2)]center dot 5H(2)O complex is the lowest value. The optical band gap value of the ligand is the highest value. The complexes decrease the angle of incidence of the ligand, while complexes increase the angle of refraction of the ligand. The electric susceptibility of the ligand decreases with its complexes.
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