Çanakkale Teknik Bilimler Meslek Yüksekokulu Koleksiyonu

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https://hdl.handle.net/20.500.12428/3540

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The Individual and Combined Effects of Electrolyzed Water and Chitosan Coating Applications on the Storage Stability of Fresh Strawberries
(Springer, 2025) Yumak Alnıak, Nesrin; Caner, Cengiz; Yüceer, Muhammed
Fresh strawberry is very susceptible to spoilage and has limited storage stability due to its fast metabolism. The main focus of this research was to evaluate if electrolyzed water (EW) (30 ppm or 90 ppm) and 1% chitosan coating can be applied individually and in combination to evaluate individual and synergistic effects on extending the storage stability of fresh strawberries. The samples were analyzed (the gas composition, pH, degrees Brix, weight loss, spoilage rate, texture as well as total anthocyanin and total phenolic composition) for the 5 weeks at 4 degrees C. At the end of storage, the O2 in the trays reduced from 21 to 13% in the groups treated with chitosan, and the CO2 ratio increased from 0.03 to 14%. The most dramatic change in gas exchange, pH, and degrees Brix occurred in the control group during storage. The decrease was less in the chitosan-coated ones. Although there is no linear change in color values (L* and a*), it can be said that EW application has a more conservative feature, especially on a*. At the end of the storage, the combination of chitosan and EW had a spoiled fruit rate of 25-30% by weight, while this rate reached 67% in the control group. The hardness value of strawberries decreases throughout storage. Although there was a decrease in total anthocyanin and total phenolic components during the 5 weeks of storage, the highest protection was measured in samples where chitosan and EW were applied together. As a result of this study, the remarkable synergistic efficacy carried out by the combined application of the chitosan coatings and the EW (30 ppm or 90 ppm) makes it an attractive promising sustainable substitute for artificial preservatives while maintaining their fresh-like quality and improved appeal within the food industry.
The efficiency of Thermosonication, Ultrasonication and pasteurization on the storage stability of fresh eggs
(Elsevier Sci Ltd, 2025) Caner, Cengiz; Gedikoğlu Arslan, Pınar; Yüceer, Muhammed
The effectiveness of ultrasonication (90 W 3.5 min.), thermosonication (52 degrees C, 90 W 3.5 min.), and pasteurization (57.5 degrees C, 25 min.) processes on the quality attributes (HU as Haugh unit, YI as yolk index, dry matter, pH, foam stability and relative foam capacity) and shell strength of fresh eggs were evaluated during storage period. The significant differences in HU values between the untreated group and the treated eggs began to be observed from the day-10. The significant differences were found in the HU both in the untreated group (47.95) and in the eggs treated with ultrasonication (55.56), thermosonication (63.64), and pasteurization (73.28), with the highest HU value found in the pasteurized eggs at day-30. It was observed that thermosonication treatments maintained higher YI values compared to the untreated group, with significant differences between the values. The pH of the albumen and yolk at all groups increased in the highest value with control (albumen 9.44 - yolk 6.44), ultrasonication (albumen 9.35 - yolk 6.34), thermosonication (albumen 9.37 - yolk 6.41), and pasteurization (albumen 9,40 - yolk 6.35). The albumen dry matter values tended to increase in all groups during the storage, with the lowest dry matter results observed in the ultrasonicated samples. The relative foam capacity (RWC) value of the eggs treated with ultrasonication (796) was higher than those of the control (626), thermosonication (735), and pasteurization (680) groups. It was highlighted that thermal treatment led to a decrease in the RWC values at day-30. The lowest shell strength values were observed in the thermosonication samples due to both the cavitation mechanism and heat. This study demonstrated that thermosonication process is efficacious in maintaining the quality attributes of the fresh shell eggs. It was found that the combination of ultrasound with heat particularly improved quality characteristics such as HU and YI. Thermosonication applications could be an important and effective alternative for enhancing the internal-quality attributes and increasing the storage stability of eggs.
Synthesis, molecular, and photophysicochemical characterizations of phthalocyanine dyes containing sodiumsulfonatenaphthalen-2-olate groups
(Elsevier, 2025) Saruhan, Serkan; Pişkin, Mehmet; Özturk, Ömer Faruk; Odabaş, Zafer
In this study, novel highly water-soluble 6-sodiumsulfonatenaphthalen-2-olate substituted phthalocyanines from the organic near-infrared dye class and contained zinc(II) or indium(III) metal ions in their cavity, were designed, and synthesized to explore their potential use as photosensitizers in photodynamic therapy. The molecular structures of the starting materials and dyes were characterized using elemental analysis, FT-IR, UV-vis, 1H-NMR, 13C-NMR, and MALDI-TOF mass spectrometry. The solubility and aggregation behaviors of these phthalocyanine dyes have been investigated in polar solvent types such as dimethylsulfoxide and N,Ndimethylformamide, ethanol, methanol, and water, as well as in phosphate-buffered saline. They have high solubility in the studied solvents and do not show any tendency to aggregate, except for water. Their photophysical and photochemical properties were investigated in N,N-dimethylformamide. The influence of the presence and position of substituents on their macrocyclic and the nature of the metal species in their cavities on their photophysical and photochemical parameters were reported. The fluorescence properties of the zinc(II) dyes studied were enhanced, while those of indium(III) dyes were low but sufficient as photosensitizers. The suitable and sufficient photophysicochemical properties of the water-soluble near-infrared new phthalocyanine dyes denote they can be potential candidates as Type II photosensitizers for photocatalytic applications.
Use of Chitosan-Coated Conductive Copper/Nanoparticle Polymer in Drug Delivery System by Encapsulation Method
(Maik Nauka/Interperiodica/Springer, 2024) Şenol Bahçeci, Dilek; Kocaeren, Aysel Aydın; Demir, Neslihan; Dalgıç, Büşra
In this study, 4-amino-3-hydroxy-1-naphthalenesulfonic acid was polymerized by the oxidative polymerization method. Copper nanoparticles of the synthesized PSa were prepared with copper sulfate solution. Structural analysis of the synthesized compounds were determined by FTIR, H-1 NMR and C-13 NMR measurements. Its optical properties were measured by UV-Vis spectrophotometer, thermal analysis by Thermogravimetric Analysis (TG) device, morphological properties by scanning electron microscope (SEM) device, and crystallographic properties by X-ray Diffraction (XRD) device. Additionally, HOMO-LUMO band gaps were calculated by determining oxidation-reduction peak potential values with the Cyclic Voltammetry (CV) device. Since CuNPs@PSa shows very good antimicrobial properties against some yeasts and bacteria, its usability in drug release was investigated. For this, Ch-CuNPs@PSa encapsulation study was carried out by coating CuNPs@PSa with chitosan (Ch). Encapsulation efficiency, loading capacity, and in vitro release kinetics were calculated. As a result, it was observed that chitosan encapsulation increased the antimicrobial effect against bacteria and yeasts and achieved the release in a controlled manner. It has been determined that Ch-CuNPs@PSa can be used in drug delivery systems as it has an Encapsulation Efficiency (EE) of 98.70%, a Loading Capacity (LC) of 78.96% and a cumulative release of 98.84%. In this case, it can be said that the obtained Ch-CuNPs@PSa can be evaluated as effective in drug release studies.
Efficacy of Chitosan-Cloisites-Nanocomposite as Sustainable Coatings on Storage Stability of Fresh Eggs
(Wiley, 2025) Atakan, Orhan; Caner, Cengiz; Yüceer, Muhammed
Fresh eggs can quickly lose their high quality if the necessary care is not taken during storage. Biocoating the fresh eggs may be a valuable option. The current study focused on developing sustainable chitosan biocoatings by adding different Cloisite clays (Cloisite 15A, 20A, and 30B) into chitosan biocoatings to seek enhancement effects on the fresh eggshell storability. The variables measured were weight loss (WL), Haugh unit (HU), yolk index, pH measurements, soluble solids, relative whipping capacity and foam stability, color analysis, lipid oxidation, viscosity, and eggshell breaking strength. The coatings increased the eggshell's storability by sealing its pores, which decreased breakage and minimized mass transfer. As a result, the lower WL occurred in the Cloisite-coated groups. The WL, which was 6.63% in the control group, was 3.63% in the group coated with chitosan-Cloisite15A combination at week 4. The HU of samples with chitosan-Cloisite15A and chitosan-Cloisite20A (60.14) had the highest HU, significantly. Chitosan-Cloisite 30B (58.78), pure chitosan (53.85), while the control (45.60) was the lowest HU. The TBARS values were measured as follows: control 1.01; chitosan 0.61, chitosan-Cloisite15A 0.39, chitosan-Cloisite20A 0.42, and chitosan-Cloisite30B 0.47 mg of malondialdehyde/kg. Cloisite15A were found to be the most effective for improving storage stability and Cloisite30 B for enhancing breaking strength. Biocoatings with Cloisite (15A, 20B, and 30B) could enhance qualities for at least 2 weeks longer.
Trends in Sustainability and Innovative Food Packaging Materials: An Overview
(Sidas Medya A.S., 2024) Caner, Cengiz; Yüceer, Muhammed; Harte, Bruce
Globally, 1.3 billion tons of food are wasted or lost every year. This loss is valued at US $2.6 trillion and accounts for 8-10% of greenhouse gas emissions (GHG). Food waste is a significant source of greenhouse gas emissions and results in a waste of natural resources. Therefore, reducing food waste can help diminish GHG emissions, improve food security, and promote healthy food systems. Packaging plays an important role in protecting food, enhancing quality and safety, and reducing food losses. Innovative and sustainable packaging strategies are necessary to decrease waste accumulation, particularly of plastics, safeguard food quality and safety, and reduce food losses and waste. Sustainable packaging aims to enhance the effectiveness of design and the use of environmentally friendly materials. This review provides an overview of the sustainable status of common packaging materials such as plastic, glass, metal, and paper/cardboard based on the circular economy, which includes recycling, reuse, composting, and bio-based packaging. The study examines new developments in food packaging materials in response to the growing demand for environmentally sustainable alternatives. Several applications from food companies and sustainable studies are discussed regarding continuous availability without impacting the environment. Ongoing research and technological advancements, such as material reduction, the development of innovative new materials like bioplastics, and improvements in recycling, will contribute to increasing the acceptance of sustainable packaging. Definitions, requirements, limitations, legislation, and applications of sustainable packaging are explored. Sustainable packaging can stimulate economic growth and offer new opportunities for companies, notably by helping the environment and reducing the carbon footprint. However, the cost of sustainable packaging can still be challenging for small businesses. Determining whether consumers are willing to pay more for sustainable packaging is also crucial in this transition. © 2024 Sidas Medya A.S.. All rights reserved.
Kripto Varlık Özelinde Üniversite Öğrencilerinin Blok Zincir Teknolojisi Bilgi Düzeylerinin İncelenmesi
(2024) Demir, Ümit; Uğurlu, Bora; Ataç, Sezgin
İnternet ve bilişim teknolojileri araçlarında meydana gelen gelişimler gelişmeler birçok alan ve işkolunun yeniden düzenlenmesine hem olanak sağlamış hem de zorunlu kılmıştır. Blok zinciri kavramı ülkemizde kripto varlıklar ile bilinirliği artan bir kavram olsa bile bilgi güvenliğinin esas olduğu dağıtık yapıda birçok sektörde gelişme potansiyeli bulunmaktadır. Bu nedenle blok zincir kavramının farklı alanlarda kullanımına yönelik bilgi yeterliliğinin önemli olduğu düşünülmektedir. Bu kapsamda gerçekleştirilen bu çalışma ile 344 lisans ve önlisans öğrencinin katılımı ile üniversite öğrencilerinin kripto para özelinde blok zinciri teknolojisine yönelik bilgi düzeylerini belirlenmesi amaçlanmıştır. Elde edilen veriler ışığında öğrencilerin çoğunun blok zinciri konusunda az ya da hiç bilgi sahibi olmadığı sonucuna ulaşılmıştır. Fakat öğrenciler kripto varlıklara yatırım düzeylerinin yüksek olduğu görülmüştür. Ayrıca öğrencilerini kripto varlıklara yatırım konusunda olumlu algılara sahip oldukları ve yatırım sürecinde sosyal çevre ve medya ortamlarının da etkisinin büyük olduğu çalışma sonucunda elde edilen önemli bulgulardandır. Elde edilen veriler ışığında tüm eğitim kademelerinde finansal okuryazarlık ve lisans seviyesinde blok zincir eğitimlerinin verilmesine yönelik öneriler getirilmiştir.
Analysis of Maarif Model of Century of Türkiye Secondary School Mathematics Curriculum According to SOLO Taxonomy
(2024) Satmaz, İsmail; Yabanova, Ulaş
Curricula are regularly updated to keep pace with social developments and scientific advancements. In this context, a new curriculum called the Maarif Model of Century of Türkiye was introduced into the Turkish Education System in 2024. Taxonomic approaches are often employed in the development of curricula; however, the specific taxonomic approach used in this curriculam has not been disclosed. The aim of this study is to analyze the secondary school Mathematics Course outcomes of the Maarif Model of Century of Türkiye Educational Program using the SOLO taxonomy. The study utilized document analysis, a qualitative research method. The outcomes were analyzed according to the SOLO taxonomy using software developed by the researchers. The results of the analysis were then reported and discussed.
ÇANAKKALE ONSEKİZ MART ÜNİVERSİTESİ TERZİOĞLU YERLEŞKESİNE SÜNGER ŞEHİR KONSEPTİ UYGULANMA POTANSİYELİNİN ARAŞTIRILMASI
(2024) Kızılaslan, Mehmet Anıl
Çanakkale Onsekiz Mart Üniversitesi Terzioğlu Kampüsü'nde gerçekleştirilen bu çalışma, kampüs alanında Sünger Şehir konseptinin uygulanabilirliğini araştırmayı amaçlamaktadır. Çalışma kapsamında mevcut duruma yönelik saha araştırmaları yapılmış ve coğrafi bilgi sistemi ortamı kullanılarak sayısal veriler elde edilmiştir. Elde edilen bulgulara göre, mevcut durumda yapılacak değişiklikler ile yerleşkenin sünger şehir konseptine yaklaştırılması mümkündür. Bu değişiklikler arasında yeşil çatı uygulamaları, geçirimsiz yüzeylerin geçirgen hale getirilmesi ve mevcut yağmur suyu drenaj sisteminin iyileştirilmesi yer almaktadır. Ayrıca, kampüs içinde yağmur bahçeleri ve yağmur suyu biriktirme haznelerinin inşa edilmesi önerilmiştir. Bu uygulamaların hayata geçirilmesi, kampüsün su kaynaklarını daha verimli kullanmasını sağlayarak çevresel sürdürülebilirliği artıracaktır. Çalışma sonucunda, Sünger Şehir konseptinin kampüs içerisinde uygulanmasının mümkün olduğu ve belirlenen alanlarda yapılacak iyileştirmelerin bu süreci destekleyeceği tespit edilmiştir. Bu tür yeşil uygulamaların, kampüsün ekolojik ayak izini azaltacağı, yağmur suyunu etkili bir şekilde biriktireceği ve iklim değişikliği ile mücadelede önemli bir rol oynayacağı sonucuna varılmıştır.
Ultrasonically sprayed cobalt oxide thin films: Enhancing of some physical properties by nickel doping
(Elsevier B.V., 2021) Kuş, Esra; Küçükkarslan, Ayşe; Demirselçuk, Barbaros; Sarıca, Emrah; Akyüz, İdris; Bilgin, Vildan
In this study, the effect of Ni doping (3, 6, 9 at%) on structural, optical, electrical and magnetic properties of Co3O4 films was reported. Films were grown at 300 ± 5 °C substrate temperature via ultrasonic spray pyrolysis (USP) technique. The structural analyses showed that undoped and Ni (3%) doped films exhibit an amorphous structure. Ni doping at higher ratios caused the films to have improved crystallinity. Optical band gap values the films were found to be between 2.03 and 2.08 eV with an additional sub-band corresponding to energies varying between 1.35 and 1.46 eV. The electrical conductivity values of the films increased significantly depending on the Ni doping. The hysteresis curves of the films showed that the films have weak ferromagnetic properties. Ni doping significantly improved the structural and electrical properties of Co3O4 films making them suitable materials for technological applications.
The effect of nanoparticle sizes on the structural, optical and electrical properties of indium sulfide thin films consisting of In2S3 and In6S7 phases
(Elsevier B.V., 2021) Demir, Ramazan; Göde, Fatma; Güneri, Emine; Emen, Fatih Mehmet
Indium sulfide thin films consisting of In2S3 and In6S7 phases were synthesized onto microscope glass substrates with different nanoparticle size using the chemical bath deposition method (CBD). Immediately after obtaining the films, they were annealed at 400°C for 1 h in reduced media in order to get better crystallization. The effect of nanoparticle sizes on the structural, compositional, optical, and electrical properties of the films was investigated. The films were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive x-ray spectrometry (EDS), UV–Vis spectroscopy and sheet resistivity measurements. The XRD spectra revealed the existence of both the cubic In2S3 and monoclinic In6S3 phases. From the SEM micrographs, the deposited films showed dense and good coverage of the surface with cracks. Moreover, nanoparticle sizes increased from 53 nm to 142 nm with increasing deposition time as well as film thickness. With an increase in nanoparticle size, the S/In ratio in the films decreased from 1.74 to 1.21 showing sulfur deficiency in the deposited films. The direct band gap (Eg) of the films decreased from 3.35 eV to 2.70 eV with increasing nanoparticle size. The sheet resistivity of the films decreased from 1.69 × 107Ω/Sq to 4.61 × 103Ω/Sq. The obtained results demonstrate that nanoparticle sizes effected the structural, compositional, optical and sheet resistivity of the films.
Length-weight relationships of fishes caught by stationary uncovered pound nets in the coastal waters of Saros Bay, North Aegean Sea (Turkey)
(Ege University Faculty of Fisheries, 2021) Çolakoğlu, Serhat
Stationary uncovered pound nets are passively fishing gears used for fish catching according to traditional methods in the coastal waters of Saros Bay, North Aegean Sea. The purpose of this study was to determine length-weight relations (LWRs) for a wide range of fish species collected from the traps in the coastal waters of Saros Bay. We are studied in the fish species caught by four traps between April and August (fishing season) in 2010 - 2012. A total of 23 fish species belonging to 12 families were caught individual 2.096. The mean value of the growth pattern (b) was 3.141 +/- 0.042, ranging from 2.711 to 3.577. Whereas they were negative allometric only for two species (Pomatomus saltatrix and Mugil cephalus), from other fish species were observed to be 13 positive allometric and 8 isometrics. The LWR parameters for the positive allometric and isometric fish species were significant (P<0.05). This study provides some general information about the status of the LWR parameters of the fish species caught from the traps.
The impact of ozone and equilibrium-modified atmosphere packaging on storage stability and health-promoting indicators of fresh Angelino plums
(Sage Publications Ltd, 2024) Caner, Cengiz; Uysal Pala, Çiğdem; Yüceer, Muhammed
Effectiveness of ozone concentrations (2, 5, and 10 ppm) and exposure time (3 and 9 min) on selected physicochemical properties (pH, soluble solids, color values (L*, a*, and b*), and texture) and health-promoting indicators such as organic acids, total phenolics (TP), and anthocyanins of Angelino fresh plums was evaluated during storage (0, 30, 90, and 120 days) in equilibrium modified atmosphere packaging (EMAP). Total anthocyanin contents and organic acid profiles were significantly affected by storage times. Malic acid (MA) was the main organic acid in Angelino plums. MA content (4663 and 4764 mg/L) was the highest value in the ozonated 2-ppm/9-min and 5-ppm/3-min than other ozonated groups and also control at 120 days of the storage. The ozone treatments especially 2-ppm/9-min and 5-ppm/3 min can significantly retard the degradation of MA content (8294 to 2688-2694 mg/L) during the storage (p < .05). Total phenol content were most significantly decreased in the control during storage, with the loss at the level of 31.7% of TPs, while the lowest one 2-ppm/9-min (20.8%) and 5-ppm/-3 min (21.9%). The color and texture are maintained for the ozone applications compared to the control during storage. Ozonation with 2-ppm/9-min and 5-ppm/-3 min showed the best performance while maintaining the storage stability based on the physicochemical properties including hardness and bioactive compounds (such as anthocyanins and organic acids), visual appearance due to the more attractive color (L*, a*, b*) the plums.
Synthesis and characterization of epoxy resins containing imine group and their curing processes with aromatic diamine
(Taylor & Francis Inc, 2019) Kaya, İsmet; Gül, Murat; Şenol, Dilek
The epoxy resins containing imine bonding were prepared from hydroxyl substituted Schiff base monomers in two steps. At the first step, hydroxyl substituted Schiff base monomers were synthesized via condensation reaction. At the second step, epoxy resins were synthesized from the reaction between Schiff base monomers and epichlorohydrine (EPC). Then curing processes of epoxy resins were achieved by p-phenylenediamine compound. The structures of resulting compounds were confirmed by FT-IR, UV-Vis and H-1-NMR. TG-DTA and DSC measurements were performed for thermal characterizations of the compounds. Chemical resistances of the cured epoxy-amine systems were determined for coating applications in acidic, alkaline and organic solvents. HCl (10%, aqueous solution), NaOH (10%, aqueous solution), DMSO, DMF, N-methylpyrrolidone, ethanol, THF and acetone were used for corrosion tests. Chemical resistance data of the synthesized epoxy resins demonstrated that they have good chemical resistance against various acid, alkaline and common organic solvents. Surface morphologies of epoxy resin and the cured epoxy resin were determined with scanning electron microscopy (SEM) measurements. Also, optical band gap (E-g) values of Schiff base monomers and epoxy resins were calculated from UV-Vis measurements.
An Examination of the Impact of Game-Based Geometric Shapes Education Software Usage on the Education of Students With Intellectual Disabilities
(Sage Publications Inc, 2022) Demir, Ümit
Purpose:This study aims to research the impact of the e-learning environment, in which game-based education software was used, on the learning of students with intellectual disabilities.Design/Approach/Methods:The study group consisted of 34 students with intellectual disabilities studying at a special education vocational school in canakkale, Turkey. In this study, the true experimental method was used. For 5 weeks, the experimental group received blended learning that was supported by the usage of a game-based education software designed by the researcher, which includes interactive educational game applications. At the same time, control group students only received the teaching process in the classroom with the traditional teaching method. A course attitude scale and an achievement test were used for data collection.Findings:The analysis of the findings showed that there was a significant increase between pre-course and post-course attitudes and academic achievement scores of the students. There wasn't a significant difference between pre-course and post-course attitudes and academic achievement scores according to the gender and academic achievement scores. Males' academic achievement and attitude post-test scores were higher than females' scores. Students having upper daily mobile devices usage experience had higher post-test and academic achievement scores than students having lower daily mobile devices usage experience.Originality/Value:This article has the potential to construct a new practice example as a supplement for analyzing the game-based educational software usage on the education of students with intellectual disabilities. As a pilot study, it provides a good sample for further investigations.
Synthesis and characterization of substituted poly(naphthalene)s with imine bonding containing thiophene unit
(Elsevier Science Sa, 2019) Şenol, Dilek; Kaya, İsmet
In this study, 5-(4H-dithieno[3,2-b:2',3'-d]pyrrol-4-yl)naphthalen-1-amine was synthesized from the required reaction conditions of 3,3'-dibromo-2,2'-bithiophene with 1,5-diamine naphthalene. Then, Schiff base monomers were synthesized from the condensation reactions of 5-(4H-dithieno [3,2-b:2',3'-d]pyrrol-4-yl)naphthalen-1-amine with mono aldehydes such as 2-hydroxybenzaldehyde, 4-hydroxybenzaldehyde and isovaniline. The Schiff base monomers were polymerized via oxidative polycondensation in 0.1 M KOH aqueous solution at 90 degrees C by 10-15% NaOCl oxidant. The structures of synthesized compounds were carried out by FT-IR, UV-Vis, H-1 NMR, C-13 NMR techniques. Further characterization was implemented by cyclic voltammetry (CV) electrochemical properties, fluorescence (FL) measurements, electrical properties, thermogravimetric-differential thermal analysis (TG-DTA) and differential scanning calorimetry (DSC) measurements. Depending on structural changes of synthesized polymers, differences were observed for the optical, electrochemical, thermal and physical properties. The optical and electrochemical band gaps, conductivity and fluorescence properties of P1 were found to be better than other polymers. The fluorescence intensity of P1 in two different wavelengths was found to be 632 a. u. and 1000 a.u. The optical (E-g) and electrochemical band gap values (E'(g)) of P1 were found to be 2.34 and 2.25 eV, respectively. This low band gap values have demonstrated to be a good conjugation in the structure. According to TG measurements, T-on temperature of P1, P2 and P3 were found to be 227, 293 and 306 degrees C, respectively. The weight average molecular weight (Mw) of P1, P2 and P3 were calculated to be 39500, 40150 and 44300 Da, respectively.
The Effect of Fe and Co doping on the Physical Properties of CdO Films Deposited by Ultrasonic Spray Pyrolysis
(Springer, 2025) Demirselçuk, Barbaros; Güneş, İbrahim; Sarıca, Emrah; Kuş, Esra; Küçükarslan, Ayşe; Bilgin, Vildan
In this study, Cadmium Oxide (CdO) semiconductor films with different iron (Fe) and cobalt (Co) concentrations have been produced at 350 degrees C substrate temperature on the glass substrates by the ultrasonic spray pyrolysis method. In the first part of this study, the Fe element was doped in different ratios (2, 4, 6%) to CdO films, and the films were characterized. At the end of this stage, the optimum Fe doping ratio was determined for CdO films. In the second step, CdO films were dually doped with Fe + Co. The electrical resistivities of CdO:Fe films were determined using a four-probe technique to measure their conductivities, carrier concentrations, mobilities, and electrical conductivity types through Hall measurements. The produced films showed n-type electrical conductivity. It was determined that with increasing doping ratios, the electrical resistivity generally increased, and the films exhibited n-type conductivity. The XRD patterns revealed that the crystal structures of the films were polycrystalline and cubic in structure. The lections of (111), (200), (220), (311), and (222) planes were observed in the XRD patterns. Upon examination of the SEM images, it was observed that the films had nearly homogeneous surfaces and good adhesion to the substrate. By utilizing the fundamental absorption spectra of the films, it was determined that they exhibited direct bandgap transitions, and the bandgap energy values ranged from 2.34 to 2.65 eV. In the structural analysis, all films were found to have a polycrystalline structure and cubic CdO crystal system. When the SEM images of CdO:(Fe + Co) films were examined, it was observed that the films had almost homogeneous surfaces. Based on all these analyses, it was concluded that the doping elements Fe and Co significantly influenced the physical properties of CdO thin films.
Humidity properties of Schiff base polymers
(De Gruyter Poland Sp Zoo, 2018) Demir, Ramazan; Kaya, İsmet
The synthesized Schiff base polymers were investigated for humidity and chloroform response characteristics. The crystal structure of polymers were analyzed using X-ray diffraction (X-RD) method. We used the QCM (quartz crystal microbalance) method for the analyses of the water steam adsorption and desorption ratio of polymers. The experimental results showed that Schiff base polymers were very sensitive to humidity and chloroform at room temperature and it was possible to use it as a sensing element in moisture sensor applications.
Comparison of electrical characteristics of zinc oxide and cadmium sulfide films covered with 8-hydroxyquinoline for diode applications
(Springer, 2019) Demir, Ramazan; Kaya, İsmet
In the present work, n-ZnO/p-8HQ and n-CdS/p-8HQ thin film heterojunctions were fabricated using spin coating and chemical bath deposition (CBD) techniques, respectively. The letter n indicates that the film is an n-type semiconductor, and the letter p is a p-type semiconductor. The thin films of ZnO covered with 8-hydroxyquinoline (8HQ) and CdS covered with 8HQ were investigated for electrical characteristics. The crystal structure of the films was investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. The optical properties of the films were investigated through a ultraviolet-visible spectrophotometer (UV-Vis spectrometer). The experimental results show that the conduction mechanism in the films is ohmic. The experimental results also reveal that ZnO thin films have diode properties with 8HQ while CdS does not have diode properties with 8HQ.
Numerical and statistical buckling analysis of laminated composite plates with functionally graded fiber orientation angles
(Sage Publications Ltd, 2020) Evran, Savaş
The aim of this numerical and statistical study was to investigate the buckling analysis of laminated composite plates containing functionally graded fiber orientation angles. The laminated composite plates had functionally graded fiber orientation angles based on Taguchi's L18 (2(1)x 3(2)) orthogonal array. The fiber orientation angles were considered to be control factors. Numerical analyses were performed using finite element software ANSYS. The optimum critical buckling load and the effects of fiber orientation angles for maximum data were determined using the analysis of the signal-to-noise ratio. The importance levels of laminates and their percent contribution on the buckling characteristics were calculated using analysis of variance. Regression analysis was employed to investigate the effects of control factors on buckling responses mathematically. The effects of laminate stacking sequence, mesh size, element type, mode number, and boundary condition were carried out using laminates with the optimum levels.

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