Matematik ve Fen Bilimleri Eğitimi Bölümü Koleksiyonu

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https://hdl.handle.net/20.500.12428/2402

Listeleniyor 1 - 20 / 31

Quark and strange quark matter in f(R) gravity for Bianchi type I and V space-times
(Springer/Plenum Publishers, 2012) Yılmaz, İhsan; Baysal, Hüsnü; Aktaş, Can
Behaviors of quark matter and strange quark matter which exist in the first seconds of the early Universe in f(R) gravity are studied for Bianchi I and V universes. In this respect, we obtain exact solutions of the modified Einstein field equations by using anisotropy feature of Bianchi I and V space-times. In particular, we investigate exact f(R) functions for Bianchi I as the contribution of strange quark and quark matter. Also, we have concluded that quark matter may contribute to the early acceleration of the universe since quark matter behaves like phantom-type dark energy. Furthermore, obtained f(R) solutions represents early eras of the Universe since f(R) solutions for quark matter coincide with f(R) equations for inflation. From this point, we can reach the conclusion that quarks may be source of the early dark energy of the universe or source of little inflation due to their repulsive force.
Domain wall solutions with quark matter in higher dimensional space-times
(Amer Inst Physics, 2007) Aktaş, Can; Yılmaz, İhsan; Baysal, Hüsnü; Aygün, Melis; Demirel, Canan
In this paper, we have examined quark matter in the perfect form attached to domain walls in the higher dimensional spherical symmetric space-time admitting one-parameter group of conformal motions. For this purpose, we have solved Einstein's field equations for higher dimensional spherical symmetric space-time via conformal motions. Also, we have discussed the features of the obtained solutions.
Chemical Oxidative Synthesis and Characterization of Poly(8-hydroxyquinoline) Particles
(Taylor & Francis Inc, 2014) Doğan, Fatih; Kaya, İsmet; Temizkan, Kevser
The chemical oxidative polymerization (OP) of 8-hydroxyquinoline (HQ) in an organic medium leaded to the formation of the C-2 and C-4 linking poly (8-hydroxyquinoline) (PHQ). The structure of PHQ was confirmed by UV-Vis, FT-IR, and H-1-NMR. The characterization of polymer was performed by TG-DTA, differential scanning calorimetry, dynamic mechanical analysis, dynamic light scattering, size exclusion chromatography, X-ray diffraction, cyclic voltammetry, atomic force microscope, photoluminescence and solubility tests. The fluorescence spectrum of PHQ exhibited an emission peak at approximately 525nm in DMSO. Accordingly, it was found PHQ emitted green light whereas HQ emitted yellow light in DMSO solvent. Optical band gaps (E-g) of PHQ was calculated to be 3.31eV. The electrical conductivities of iodine doped-PHQ and undoped-PHQ were measured with four-point probe technique. Magnetic particles was prepared by chemical precipitation of mixed Fe(II) and Fe(III) salts and modified with HQ by using an in situ chemical oxidation polymerization method in organic medium.
Non-isothermal degradation kinetics of poly (2,2'-dihydroxybiphenyl)
(Springer, 2009) Doğan, Fatih; Kaya, İsmet; Bilici, Ali
Catalytic oxidative polymerization of 2,2'-dihydroxybiphenyl (DHBP) was performed by using Schiff base polymer-Cu (II) complex and hydrogen peroxide as catalyst and oxidant, respectively. According to size exclusion chromatography (SEC) analysis, the number-average molecular weight (M (n)), weight-average molecular weight (M (w)) and polydispersity index (PDI) values of poly (2,2'-dihydroxybiphenyl) (PDHBP) were found to be 37,500, 90,000 g mol(-1) and 2.4, respectively. The thermal degradation kinetics was investigated by thermogravimetric analysis in dynamic nitrogen atmosphere at four different heating rates: 5, 10, 15 and 20 A degrees C min(-1). The derivative thermogravimetry curves of PDHBP showed that its thermal degradation process had one weight-loss step. The apparent activation energies of thermal decomposition for PDHBP as determined by Tang, Flynn-Wall-Ozawa (FWO), Kissenger-Akahira-Sunose (KAS), Coats-Redfern (CR) and Invariant kinetic parameter (IKP) methods were 109.1, 109.0, 110.0, 108.4 and 109.8 kJ mol(-1), respectively. The mechanism function and pre-exponential factor were determined by master plots and Criado-Malek-Ortega method. The most likely decomposition process was a D (n) Deceleration type in terms of the CR, master plots and Criado-Malek-Ortega results.
Azomethine-based phenol polymer: Synthesis, characterization and thermal study
(Elsevier Science Sa, 2011) Doğan, Fatih; Kaya, İsmet; Bilici, Ali
Azomethine-based phenol polymer, poly-2-{[(6-aminopyridin-2-yl)imino]methyl}-phenol (PAPIMP), was synthesized through the combination of condensation reaction and oxidative polymerization. Polymer isolated from aqueous solution was characterized by UV-vis, FT-IR, NMR and TG, SEC analysis. According to the SEC chromatograms, the number-average molecular weight (M(n)), weight-average molecular weight (M(w)) and polydispersity index (PDI) values of PAPIMP were determined to be 33,550, 78,900 g mol(-1) and 2.352, respectively. Also, optical band gaps (E(g)) of APIMP and PAPIMP calculated from cyclic voltammetry (CV) measurements. Also, electrical conductivities of each component measured with four-point probe technique. TG analysis showed that PAPIMP was stable up to 300 degrees C. The thermal decomposition kinetics of PAPIMP was investigated by means of thermogravimetric analysis in dynamic nitrogen atmosphere at four different heating rates: 5, 10, 15 and 20 degrees C min(-1) The apparent activation energies for thermal decomposition of PAPIMP were obtained by Tang, Flynn-Wall-Ozawa (FWO), Kissenger-Akahira-Sunose (KAS) and Coats-Redfern methods (CR) were 96.97, 105.33, 97.28 and 88.60 kJ mol(-1), respectively; the mechanism function and pre-exponential factor were determined by master plots method. The most likely decomposition process was a D(n) Deceleration type in terms of the Coats-Redfern and master plots results. (C) 2010 Elsevier B.V. All rights reserved.
Monomer/polymer Schiff base copper(II) complexes for catalytic oxidative polymerization of 2,2′-dihydroxybiphenyl
(Wiley, 2009) Bilici, Ali; Kaya, İsmet; Doğan, Fatih
Catalytic oxidative polymerization of 2,2'-dihydroxybiphenyl (DHBP) was performed by using both the Schiff base monomer-Cu(II) complex and Schiff base polymer-Cu(II) complex compounds as catalysts and hydrogen peroxide as oxidant, respectively. The dependence of monomer conversion and molecular weight distribution on various reaction parameters, including time, temperature, solvent as well as the amount of catalyst and oxidant were investigated. The structure of the poly-2,2'-dihydroxybiphenyl (PDHBP) was confirmed by UV-vis, IR, H-1 and C-13 NMR spectroscopy techniques. The electrochemical and thermal properties of PDHBP were also studied. DSC data revealed that PDHBP was amorphous. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2977-2984, 2009
Regioselectively functionalized synthesis of poly(amino naphthalene disulfonic acid)
(Elsevier Science Sa, 2016) Doğan, Fatih; Kaya, İsmet; Temizkan, Keyser
Here, we reported the regioselective formation of poly(amino naphthalene disulfonic acid) (PANDA) nanoparticles by a template-free polymerization process in an aqueous alkaline medium. The NMR, FT-IR, UV-vis, gel permeation chromatography (GPC), thermogravimetry (TG), differential scanning calorimetry (DSC), cyclic voltammetry (CV), photoluminescence (PL), dynamic light scattering (DLS), X-Ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and conductivity techniques were used to investigate the structure characterization in addition to the chemical and physical properties of PANDA polymer-based nanoparticle with molecular weight ca. 14000 Da. Polymer-based nanoparticle showed a reversible redox behavior because of its electroactive nature. PANDA, also, emitted a yellow light while ANDA typically emitted a blue light in DMSO. PANDA displayed an uncommon high photoluminescence quantum efficiency of approximately 30%. The kinetic parameters related to the solid state thermal decomposition of the poly-nanoparticles were calculated from isoconversional methods based on multiple heating rates by TG-DTG/DTA curves. (C) 2016 Elsevier B.V. All rights reserved.
Meslek Bilgisi Derslerinin Öğretmen Adaylarının Profesyonel Gelişimindeki Önemi
(Pamukkale Üniversitesi, 2010) Şahin Taşkın, Çiğdem; Hacıömeroğlu, Güney
Bu araştırma öğretmen adaylarının meslek bilgisi dersleri üzerine bakış açılarını ortaya koymayı amaçlamaktadır. Araştırmaya Marmara bölgesinde yer alan bir üniversitenin, Eğitim Fakültesi, İlköğretim Bölümü Sınıf Öğretmenliği ve Okul Öncesi Öğretmenliği A.B.D. son sınıfında öğrenim gören toplam 72 öğretmen adayı katılmıştır. Bu çalışmada, veriler nitel araştırma yöntemlerinden açık uçlu soru tekniği kullanılarak toplanmıştır. Elde edilen bulgular, Sınıf Öğretmenliği öğretmen adaylarından 38inin, Okul Öncesi öğretmenliği öğretmen adaylarından ise 20sinin meslek bilgisi derslerinin öğretmenlik mesleğine bakış açılarını olumlu yönde etkilediğini ifade ettiklerini göstermektedir. Bununla beraber, bazı öğretmen adayları bu dersleri yeterli bulmadıklarını, bazıları ise derslerin mesleğe bakış açılarını değiştirmediğini belirtmiştir.
Investigation of Some Properties of 4-Amino-2-Methyl-Quinoline and CdS Nano Composite Thin Films for Production of Diodes
(2024) Demir, Ramazan; Kaya, İsmet
The aim of this study is to produce a diode, which is a basic electronic circuit element, and analyze its physical characterization. In this study, a diode was produced from CdS and C10H10N2 films, and its structural, optical, and electrical properties were investigated. First, a thin CdS film was deposited on an ITO substrate using the CBD method. Then, a C10H10N2 film was coated on this CdS film by the spin coating method. The CdS film has n-type semiconductor properties, whereas the C10H10N2 film has p-type semiconductor properties. XRD, SEM, AFM, UV-Vis spectroscopy, and IV measurements were performed on the produced films. According to the XRD result, a sharp peak at 27.07° was observed in the hexagonal phase of CdS. At this angle, a grain size of 33.3 nm was calculated according to the XRD result. Based on the SEM and AFM measurement results, it was determined that the film surface was uniform and dotted. According to the UV-Vis results, in addition to the d→d* transition, π→π* and n→π* transitions were also observed. From the I-V diagram, it was seen that the heterojunction structure of the CdS/C10H10N2 films had a diode property. The value of rectification factor was calculated as 2.91x102 from the I-V data. In addition, the ideality factor was calculated as 1.93 using the traditional method.
A Kinetic Evaluation for PANSA Doped Low Density Polyethylene Blends
(2019) Doğan, Fatih; Bilici, Ali; Kaya, İsmet; Şirin, Mehtap
In our previous study, we prepared blends of lowdensity polyethylene (LDPE) with semiconductorpolymer, poly (1-amino-2-hydroxynaphthalene-4-sulfonic acid) (PANSA), in different mixing ratios. Inthat study, the findings on some physical and chemical properties of the blends prepared were alsopresented. In this study, it was aimed to investigate the thermal decomposition kinetics of these preparedblends. For this purpose, thermograms of PANSA doped LDPE blends at four different heating rates wereobtained. With the addition of PANSA into LDPE, it was observed that the initial decompositiontemperature and maximum decomposition temperature of LDPE increased. Thermal decompositionkinetics of blends were performed using the integral isoconversional methods (Kissinger, Kim-Park (KP),Tang, Kissenger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO)) in addition to differentialisoconversional method (Friedman method). The activation energy values calculated by Kissinger, KP,Tang, KAS, FWO and Friedman methods and found to be 187.9, 200.2, 171.90, 171.78, 171.70 and171.89 kJ mol-1for 0.5 % PANSA doped LDPE, 193.9, 206.2, 173.31, 172.87, 172.98 and 172.78 kJmol-1for 1 % PANSA doped LDPE and 207.0, 219.2, 196.94, 197.09, 198.08 and 208.10 kJ mol-1for 0.5% PANSA doped LDPE, respectively. Thermal decomposition mechanism for blends was proposed withthe help of master plot curves.
Synthesis and Characterization and Thermal Decomposition Kinetics of Poly (quinoline)-Copper Composite
(2018) Bilici, Ali; Tezel, Ruhiye Nilay; Kaya, İsmet; Doğan, Fatih
In here, chemical oxidative synthesis of a new poly(quinoline)-coppercomposite was given in one-step pathway. To obtain composite, the coppersulphate and 2-amino-8-quinolinol were used as oxidant and monomer,respectively. The oxidation product obtained was characterized by FTIR, UV-Vis,thermogravimetry (TG), photoluminescence (PL), SEM-EDX, TEM analysis and solidstate conductivity measurements. SEM observations exhibited the presence of a plate-like heterogeneousmorphology. Rod like structures was revealed from TEM images. TEM studies also indicated that the coppernanoparticles were almost uniformly distributed on polymer. The thermaldecomposition kinetics of oxidation product were also studied. For this, the differentmethods such as Coats-Redfern, Flynn-Wall-Ozawa, Tang and Kissinger-Akahira-Sunose were used.
The Effects of Blog-Based Learning on Pre-service Science Teachers' Internet Self-efficacy and Understanding of Atmosphere-Related Environmental Issues
(Springer Science and Business Media Deutschland GmbH, 2021) Kahraman, Sakıp
The aim of the study was to investigate the effects of blog-based learning (BBL) on pre-service science teachers’ Internet self-efficacy and understanding of atmosphere-related environmental problems (AREPs). The working group of the study consisted of 89 pre-service science teachers. The participants were divided into groups, and each group was asked to perform the following activities in sequence: (1) accessing scientific documents (e.g. articles, books) and reading them individually, (2) coming together in groups to discuss the scientific knowledge extracted by each group member and preparing a presentation about the issue discussed, (3) sharing findings and engaging groups in a discussion of issues, and (4) developing a blog using the knowledge from the discussions within and between groups. In this study, single-group pretest-posttest experimental design was used. To collect data, the Internet Self-efficacy Scale (ISS), the Atmosphere-related Environmental Problems Diagnostic Test (AREPDiT), and the Opinion Questionnaire about Blogging (OQaB) were used. The results revealed that the subjects’ ISS and AREPDiT post-test mean scores were significantly higher than their pre-test mean scores and that their misconceptions about AREPs were substantially eliminated by the intervention. The subjects’ responses to the blog use were generally positive.
Electrocatalytic oxidation and flow injection analysis of formaldehyde at binary metal oxides (Co3O4-NiO and CuO-Co3O4) modified pencil graphite electrodes
(Springer, 2021) Emir, Gamze; Karakaya, Serkan; Ayaz, Selen; Dilgin, Didem Giray; Dilgin, Yusuf
In this work, a highly efficient performance of bimetallic thin films as their oxide forms (Co3O4-NiO and CuO-Co3O4) modified on pencil graphite electrodes (PGEs) was presented for electrocatalytic oxidation of formaldehyde. In addition, a sensitive and selective amperometric determination of formaldehyde in flow injection analysis system have been first performed using binary transition metal oxides modified PGEs. Co3O4-NiO and CuO-Co3O4 films were electrochemically deposited on the PGE surface using cyclic voltammetric procedures. The recorded cyclic voltammograms in the presence of formaldehyde in 0.10 M NaOH containing 0.10 M KCl showed that the prepared binary transition metal oxides modified PGEs exhibited a higher electrocatalytic activity than single metal oxide thin films modified PGEs towards oxidation of formaldehyde. The linear responses based on electrocatalytic oxidation of formaldehyde were determined as 2.5-5000 mu M and 0.25-1000 mu M for Co3O4-NiO/PGE and CuO-Co3O4/PGE, respectively. Moreover, limit of detections and sensitivities were estimated as 0.73 mu M and 81.8 mu A mM(-1) cm(-2) and 0.09 mu M and 166 mu A mM(-1) cm(-2) for Co3O4-NiO/PGE and CuO-Co3O4/PGE, respectively. The results from real sample studies proved that the fabricated FI-amperometric sensors enable high applicability towards determination of formaldehyde in real water samples.
Anti-bacterial, anti-oxidant activities of polymer-based metal complexes and their catalyst effects in presence of H2O2
(Springer Science and Business Media Deutschland GmbH, 2024) Şenol Bahçeci, Dilek; Aydın Kocaeren, Aysel; Demir, Neslihan; Dalgıç, Büşra
4-{[(3-Hydroxynaphthalen-2-yl)imino]methyl}benzene-1,2,3-triol Schiff-base, abbreviated as ligand (L), was synthesized and additionally, its polymer was obtained through oxidative polycondensation and named as poly-4-{[(3-hydroxynaphthalen-2-yl)imino]methyl}benzene-1,2,3-triolpoly-ligand (PL). The ammonium persulfate (NH4)2S(2)O(8) was used as an oxidant in this reaction. The metal complexes of PL were synthesized in the presence of various metal ions such as Cu2+, Hg2+, Ni2+, Pb2+,and Zn2+. The synthesized structures of PL and metal complexes were confirmed by FTIR, UV-vis, H-1 and C-13 NMR, and elemental analysis. Moreover, SEM and TGA analyses were performed for characterization. In this study, the anti-oxidant, anti-bacterial and catalytic properties of PL and its metal complexes were investigated. For anti-oxidant properties, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) detection methods were studied. Also, for anti-bacterial activities they were tested against various bacteria using the minimum inhibitory concentration (MIC) method. It was observed that [Ni(PL)(2)] and [Pb(PL)(2)] metal complexes showed quite good anti-oxidant activities when they were compared with PL at its highest concentration of 100 ppm. The anti-bacterial activity results showed that [Hg(PL)(2)] had the highest MIC value of all the mentioned materials. The obtained catalytic activity results revealed that the synthesized poly-ligand metal [M(PL)(2)] complexes could be considered as an alternative catalyst to remove various organic pollutants from the aqueous environment. From this point of view, it is possible to say that [M(PL)(2)] complexes synthesized within the scope of the study could be used as polymeric agents to reduce environmental pollution.
Simple, sensitive, and cost-effective voltammetric determination of salbutamol at a pencil graphite electrode modified with Nafion and functionalized multi-walled carbon nanotubes
(Springer, 2024) Dilgin, Didem Giray; Vural, Kader; Karakaya, Serkan; Dilgin, Yusuf
This study describes a simple, highly sensitive, and cost-effective electrochemical determination of salbutamol (SBT) at a disposable pencil graphite electrode modified with Nafion/functionalized multi-walled carbon nanotubes composite material (Nf/f-MWCNTs/PGE). The electrochemical response of SBT at this modified electrode was investigated by both differential pulse voltammetry (DPV) and cyclic voltammetry techniques. The voltammetric measurements confirmed that the combination of f-MWCNTs with Nafion shows remarkable electrocatalytic activity on the oxidation of SBT due to a synergistic effect of Nafion via electrostatic interaction and f-MWCNTs via excellent conductivity and large specific surface area. Differential pulse voltammetry results show that the composite electrode gives two linear ranges of 0.10-17.5 mu M and 17.5-100 mu M with a detection limit (LOD) of 0.027 mu M SBT. Moreover, the studies of some potential interferants show that there is no significant interference in the determination of SBT. The proposed procedure was successfully applied to determine SBT in tube- and syrup-type pharmaceutical formulations, animal feed, and beef meat samples, and acceptable results were obtained with high accuracy and precision. Moreover, the proposed sensor displays good intra-day and inter-day precisions for the voltammetric determination of SBT.
Voltammetric Determination of Favipiravir Used as an Antiviral Drug for the Treatment of Covid-19 at Pencil Graphite Electrode
(John Wiley and Sons Inc, 2023) Erşan, Teslime; Dilgin, Didem Giray; Kumrulu, Elif; Kumrulu, Umur; Dilgin, Yusuf
This work describes the sensitive voltammetric determination of favipiravir (FAV) based on its reduction for the first time with a low-cost and disposable pencil graphite electrode (PGE). In addition, the determination of FAV was also performed based on its oxidation. Differential pulse (DP) voltammograms recorded in 0.5 M H2SO4 for the reduction of FAV show that peak currents increase linearly in the range of 1.0 to 600.0 μM with a limit of detection of 0.35 μM. The acceptable recovery values (98.9–106.0 %) obtained from a pharmaceutical tablet, real human urine, and artificial blood serum samples spiked with FAV confirm the high accuracy of the proposed method.
Streamline analysis of MHD flow in a double lid-driven cavity
(SAGE Publications Ltd, 2023) Çelik, Ebutalib; Guerbuez-Caldağ, Merve
The magnetohydrodynamic flow of an incompressible, steady and electrically conducting fluid is considered in double lid-driven square cavity under an inclined magnetic field. The non-dimensional governing equations are solved numerically using a radial basis function (RBF) approximation meshless method in order to obtain the flow patterns. Hartmann number (Formula presented.) and the inclination angle of magnetic field (Formula presented.) are taken as a problem variables that produce various flow transformations by their variation for (Formula presented.). Streamlines are examined topologically, and it has been observed that the inclination angle and strength of magnetic field have different influence on the bifurcation of flow structures.
Voltammetric determination of Molnupiravir used in treatment of the COVID-19 at magnetite nanoparticle modified carbon paste electrode
(Elsevier Inc., 2023) Vural, Kader; Karakaya, Serkan; Dilgin, Didem Giray; Gökçel, Hatice İsmet; Dilgin, Yusuf
To reduce the progression of the viral process in patients infected with COVID-19, new treatments and drug active substances are needed. One of these drugs is Molnupiravir (MNP) which has a direct antiviral effect and has also proven to be highly effective in reducing the azopharyngeal SARS-CoV-2 infectious virus and viral RNA. Due to the importance and frequent use of this drug in the treatment of COVID-19, its accurate, quick, and cheap detection in pharmaceutical or biological samples is crucial. In this work, electrochemical behavior and sensitive voltammetric determination of MNP are described using a magnetite nanoparticle modified carbon paste electrode (Fe3O4@CPE) for the first time. Fe3O4 nanoparticles (NPs) were characterized by recording their transmission electron microscopy (TEM) images, energy dispersive X-ray (EDX), and X-ray diffraction (XRD) spectra. Cyclic voltammetric measurements showed that MNP was irreversibly oxidized at Fe3O4@CPE at 760 mV in pH 2.0 Britton Robinson buffer solution (BRBS). The peak current of MNP was increased approximately threefold at Fe3O4@CPE compared to bare CPE due to a good electrocatalytic efficiency of Fe3O4 NPs. According to differential pulse voltammetric studies, the fabricated electrode exhibited a linear range (LR) between 0.25 and 750 µM with sensitivity and limit of detection (LOD) of 4591.0 µA mM−1 cm−2 and 0.05 µM, respectively. On the other hand, although lower sensitivity (327.3 µA mM−1 cm−2) was obtained from CV compared to DPV, a wider linear calibration curve between 0.25 and 1500 µM was obtained in CV. Studies performed in tablet samples confirmed that the Fe3O4@CPE exhibits high applicability for selective and accurate voltammetric determination of MNP in real samples.
Öğretmen Adaylarının Bilimin Doğası Öğretimine Yönelik Anlayışlarının Değerlendirilmesi
(Hacettepe Üniversitesi, 2021) Çavuş Güngören, Seda; Hamzaoğlu, Ergin
Bu çalışmanın amacı, fen bilgisi öğretmen adaylarının bilimin doğası öğretimine ilişkin anlayışlarını değerlendirmektir. Ayrıca farklı öğretim yöntemlerine odaklanmanın bu konuda oluşturabileceği farklılıklar incelenmiştir. Araştırmaya bir devlet üniversitesinin 3. sınıfında okuyan 41 fen bilgisi öğretmen adayı katılmıştır. Çoklu durum çalışması olarak tasarlanan araştırma, bilimin doğası ve bilim tarihi dersi kapsamında gerçekleştirilmiştir. Ders kapsamında öğretmen adaylarına bilimin doğası, öğretiminin önemi, öğretim programındaki yeri, ortak bilgi yapılandırma modeli ve bağlam temelli öğretim yaklaşımı konularında eğitim verilmiştir. Veri toplama aracı olarak bilimin doğası öğretimi hakkındaki açık uçlu sorular, yarı yapılandırılmış görüşmeler ve günlükler kullanılmıştır. Verilerin analizinde betimsel analiz kullanılmış ve beş boyutta çözümlenmiştir. Bu boyutlar; bilimin doğası içeriğinin öğretimi, bilimin doğası öğretiminin kazandırdıkları, bilimin doğası öğretiminin içeriği, öğretmenin-öğrencinin rolü ve görüş belirtmedi olarak ele alınmıştır. Araştırma sonuçları öğretmen adaylarının bilimin doğası öğretimine yönelik anlayışlarının yeterli olduğunu göstermiştir. Öğretmen adaylarının farklı öğretim yöntemlerine odaklanmaları bilimin doğası öğretimine yönelik anlayışlarında ilgili boyutlar açısından önemli bir farklılaşmaya neden olmadığı belirlenmiştir.
Quantum dots-based photoelectrochemical sensors and biosensors
(Elsevier, 2021) Dilgin, Yusuf; Karakaya, Serkan; Dilgin, Didem Giray
Photoelectrochemistry has been one of the most frequently studied branches of chemistry for the past 2 decades and its principle is based on monitoring a photocurrent generated by the irradiation of photosensitive material on an electrode surface with a light source. Photoelectrochemical (PEC) analysis has found wide applications in various fields such as water splitting, hydrogen or oxygen production, pollutant degradation, CO2 reduction, and construction of sensors and biosensors. In PEC studies, various photosensitive materials such as organic redox mediators (ORMs), semiconductors, heterostructures, and composite nanomaterials have been used. Among these, quantum dots (QDs) are of great interest to researchers because of their unique and superior optical and electronic properties. In this chapter the principles and mechanisms of PEC-sensing strategies using ORMs, QDs or their hybrid nanostructures are described and applications of PEC-sensing platforms such as in small analyte detection, immunoassays, nucleic acids, and enzyme-based biosensors.

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