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Impact of Temperature Optimization of ITO Thin Film on Tandem Solar Cell Efficiency
Get PDFThis study examined the impact of temperature optimization on indium tin oxide (ITO) films in monolithic HJT/perovskite tandem solar cells. ITO films were deposited using magnetron sputtering at temperatures ranging from room temperature (25 degrees C) to 250 degrees C. The sputtering target was ITO, with a mass ratio of In2O3 to SnO2 of 90% to 10%. The effects of temperature on the ITO film were analyzed using X-ray diffraction (XRD), spectroscopic ellipsometry, and sheet resistance measurements. Results showed that all ITO films exhibited a polycrystalline morphology, with diffraction peaks corresponding to planes (211), (222), (400), (440), and (622), indicating a cubic bixbyite crystal structure. The light transmittance exceeded 80%, and the sheet resistance was 75.1 Omega/sq for ITO deposited at 200 degrees C. The optical bandgap of deposited ITO films ranged between 3.90 eV and 3.93 eV. Structural and morphological characterization of the perovskite solar cell was performed using XRD and FE-SEM. Tandem solar cell performance was evaluated by analyzing current density-voltage characteristics under simulated sunlight. By optimizing the ITO deposition temperature, the tandem cell achieved a power conversion efficiency (PCE) of 16.74%, resulting in enhanced tandem cell efficiency.Scientific and Technological Research Council of Turkey (TUBITAK) [20AG002, 20AG014]This research was partially supported by The Scientific and Technological Research Council of Turkey (TUBITAK) with project numbers 20AG002 and 20AG014
A NOVEL MACHINE LEARNING STUDY: MAXIMIZING THE EFFICIENCY OF PARABOLIC TROUGH SOLAR COLLECTORS WITH ENGINE OIL-BASED COPPER AND SILVER NANOFLUIDS
Get PDFEstimating the heat transfer parameters of parabolic trough solar collectors with machine learning is crucial for improving the efficiency and performance of these renewable energy systems, optimizing their design and operation, and reducing costs while increasing the use of solar energy as a sustainable power source. In this study, the heat transfer characteristics of two different nanofluids flowing through the porous media in a straight plane underneath thermal jump conditions were investigated by machine learning methods. For the flow in the parabolic trough solar collector, two different nanofluids obtained from silver- and copper-based motor oil are considered. Flow characteristics were obtained by nonlinear surface tension, thermal radiation, and Cattaneo-Christov heat flow, which was used to calculate the heat flow in the thermal boundary layer. A neural network structure was established to estimate the skin friction and Nusselt number determined for the analysis of the flow characteristic. The data used in the multilayer neural network, which was developed using a total of 30 data sets, were divided into three groups as training, validation, and testing. In the input layer of the network model with 15 neurons in the hidden layer, 10 parameters were defined and four different results were obtained for two different nanofluids in the output layer. The prediction performance of the established neural network model has been comprehensively studied by means of several performance parameters. The study findings presented that the established artificial neural network can predict the heat transfer characteristics of two different nanofluids obtained from silver- and copper-based motor oil with deviation rates less than 0.06%.ACKNOWLEDGMENT The author expresses gratitude to Abu-Hamdeh et al. (2021) for their research in the field of renewable energy, their scientific contribution, and for providing an open source datase
Hydrogen storage capacity of two-dimensional MoS2
Get PDFHydrogen storage holds a crucial place for the future of the world in terms of green energy. Two-dimensional materials, in particular, are important in this regard. The aim of this study is to evaluate the performance of MoS2 which is one of the most popular member of two-dimensional materials family. To do this, bulk and exfoliated MoS2 were used. Firstly, the liquid phase exfoliation method was employed to obtain exfoliated MoS2 layers. Then, the hydrogen storage potential of the bulk and exfoliated MoS2 was addressed under 1, 3, 5, 7, and 9 bar hydrogen pressure. After the absorption process, all the samples were characterized using XRD, Raman Spectrometer, and BET ahead of evaluating their hydrogen storage potential. The XRD pattern showed that the peak positions of bulk and exfoliated MoS2 were not affected critically by hydrogen storage. In the Raman spectra, the A1g and E2g 1 peaks of all hydrogenated materials shifted to low wavelengths. Moreover, the BET measurements revealed that the specific surface area and the pore size of the bulk MoS2 were 12.31 m2/g and <= 67.46 nm respectively. Additionally, the specific surface area and the pore size of the exfoliated MoS2 were 23.16 m2/g and <= 69.28 nm, respectively. The hydrogen storage potential of the bulk and the exfoliated MoS2 was evaluated through an MFC in sccm unit. The bulk and exfoliated MoS2 stored 220 and 450 sccm hydrogen, respectively. Besides, the weight percent hydrogen storage for H-MoS2 and H -exfoliated MoS2 was determined to be 1.2 and 2.4 wt%, respectively. In summary, this study has shown that exfoliated MoS2, one of the twodimensional materials, can play a critical role for hydrogen storage due to their high specific surface area.Scientific and Technological Research Council of Turkey, Turkey (TUBITAK) [122F333]; Council of Higher Education (YOK)This research was supported by The Scientific and Technological Research Council of Turkey, Turkey (TUBITAK) with project number 122F333. The author, Ali ALTUNTEPE would like to thank the Council of Higher Education (YOK) for the 100/2000 Ph.D. Scholarship Program
Impacts of Pulsed Electric Fields (PEF) Pre-treatment on the Characteristics of Fried Yellow- and Purple-Fleshed Potatoes: a Chemometric-Assisted FTIR Study
Get PDFPulsed electrical field (PEF) treatment with 1 kJ/kg and 3 kJ/kg of energies was applied to yellow- and purple-fleshed potatoes before frying (180 degrees C for 2 min). The effects of PEF on oil content, colour and bioactive compounds were investigated. Significant oil reductions were observed for PEF-treated potatoes, >= 20% for yellow- and >= 24% for purple-fleshed potatoes, and this was also confirmed in the Fourier transform infrared (FTIR) graph. PEF-treated potatoes had significantly higher phenolic compounds and antioxidant activity than those of untreated samples. Moreover, although the frying reduced total monomeric anthocyanin (TMA) contents of the purple-fleshed potato samples compared to raw potato samples (not PEF-treated and not fried), PEF-treated samples had significantly higher TMA than the untreated (not PEF-treated but fried) samples. Raw samples and fried samples were separated according to PC1 (principal component 1) in chemometric analysis, and fried samples with and without PEF treatment were also separated according to PC2 (principal component 2). When PLS (partial least squares) regression graphs were examined, it was revealed that there was a very good correlation between the oil content and redness (a*) values calculated and estimated by FTIR spectroscopy. Our study showed that PEF treatment could be succesfully used for different varieties of potato before frying
The Protective Effects of Nigella Sativa on the Antioxidant System and Certain Cytokine Levels in Rats Exposed to Experimental Acrylamide
Get PDFAim: The objective of this research was to examine the potential safeguarding properties of Nigella sativa (N. sativa) against the genotoxic, carcinogenic, and neurotoxic effects of acrylamide. N. sativa is known for its strong antioxidant and anti-inflammatory characteristics which can counteract the detrimental impact of environmental toxins. The research investigated the influence of N. sativa on the antioxidant system and pro-inflammatory cytokines, and explored its therapeutic potential in rats exposed to acrylamide, a substance known for its harmful effects on various systems. Materials and Methods: Thirty-two healthy adult male rats were used and allocated into four separate groups: control, acrylamide, N. sativa, and acrylamide + N. sativa groups. Acrylamide (40 mg/kg/day) and N. sativa oil (10 mg/kg/day) were given orally for 15 days. IL-1, IL-6, IL-10, SOD, glutathione, malondialdehyde, and TNF-? levels were analyzed. Results: The acrylamide group exhibited a significant increase in MDA levels in comparison to the other groups, indicating oxidative stress (P < 0.05). Moreover, GSH and SOD levels were appreciably lower in the acrylamide group (P < 0.05). Conversely, the experimental group treated with N. sativa displayed reduced MDA levels (by approximately 30%) and improved GSH and SOD levels compared to the acrylamide group, suggesting a significant protective effect against acrylamide toxicity (P < 0.05). The acrylamide group showed significantly increased levels of pro-inflammatory cytokines, including TNF-?, IL-6, and IL-1, along with a notable decrease in the antiinflammatory cytokine IL-10 (P < 0.05). Conversely, in the group treated with N. sativa, there was a significant reduction in the concentrations of TNF-?, IL-6 and IL-1 (P < 0.05), indicating the anti-inflammatory effects of N. sativa. Conclusion: The study results suggest that N. sativa can alleviate acrylamideinduced oxidative stress and inflammation. It seemed that N. sativa significiantly improved the increase of MDA levels altered by ACR and increase antioxidant levels, and partially attenuate the changes in L-1 levels induced by ACR. These findings indicate that N. sativa suggests potential benefits in alleviating the adverse impacts of acrylamide
Promising the potential of ?-caryophyllene on mercury chloride-induced alteration in cerebellum and spinal cord of young Wistar albino rats
Get PDFMercury chloride (ME) is a chemical pollutant commonly found in the environment, which can contribute to undesirable health consequence worldwide. The current study investigated the detrimental impact of ME on the cerebellum and spinal cord tissues in 6-8-week-old female rats. We also evaluated the neuroprotective efficacy of beta-caryophyllene (BC) against spinal and cerebellar changes caused by ME. Thirty-five young Wistar albino rats were randomly chosen and assigned into five groups: control (CO), olive oil (OI), ME, BC, ME + BC. All samples were analysed by means of unbiased stereological, biochemical, immunohistochemical, and histopathological methods. Our biochemical findings showed that SOD level was significantly increased in the ME group compared to the CO group (p < 0.05). We additionally detected a statistically significant decrease in the number of cerebellar Purkinje cells and granular cells, as well as spinal motor neuron in the ME group compared to the CO group (p < 0.05). In the ME + BC group, the number of Purkinje cells, granular cells, and spinal motor neurons was significantly higher compared to the ME group (p < 0.05). Decreased SOD activity in the ME + BC group was also detected than the ME group (p < 0.05). Immunohistochemical (the tumour necrosis factor-alpha (TNF-alpha)) and histopathological examinations also exhibited crucial information in each of the group. Taken together, ME exposure was associated with neurotoxicity in the cerebellum and spinal cord tissues. BC treatment also mitigated ME-induced neurological alteration, which may imply its potential therapeutic benefits.The research was supported by Karabuk University Scientific Research FundNo Statement Availabl
Konya population in the Republican era (1927-1950)
Get PDFSosyal Bilimler Enstitüsü, Tarih Ana Bilim DalıTürkiye Cumhuriyeti'nin kurulmasının ardından, Büyük Millet Meclisi daha kapsamlı bir nüfus sayımını garanti altına almak için bir yasa çıkarmıştır. Bu son nüfus sayımı sadece erkek ve kadın sayısını belgelemekle kalmamış, aynı zamanda toplanacak bilgilerin kapsamını da genişletmiştir. Nüfus cinsiyet, medeni durum, okuryazarlık, eğitim, dini aidiyet, yaş grupları ve diğer ilgili faktörlere göre sınıflandırılmıştır. Bu araştırma, Türkiye Cumhuriyeti'nde 1927-1950 yılları arasında Konya ilinde yapılan nüfus sayımlarını bağlamında analiz etmeyi amaçlamaktadır. Konya ilinin nüfus ve demografik yapısının analizi 1927, 1935, 1940, 1945, 1950, 1955 ve 1960 nüfus sayımı verileri kullanılarak yapılmıştır.Following the establishment of the Republic of Turkey, the Grand National Assembly passed a law to guarantee a more comprehensive census. This latest census not only documented the number of men and women, but also expanded the scope of information to be collected. The population is classified according to gender, marital status, literacy, education, religious affiliation, age groups and other relevant factors. This research aims to analyze the population censuses conducted in the province of Konya between 1927 and 1950 in the Republic of Turkey. The analysis of the population and demographic structure of Konya province was made using 1927, 1935, 1940, 1945, 1950, 1955 and 1960 census data
Ultrasound-enhanced dispersive solid phase extraction of Cd (II), Co (II), and Ni (II) using magnetic Pinus pinea
Get PDFA new ultrasound assisted dispersive solid phase extraction (DSPE) technique has been combined with flame atomic absorption spectrometry (FAAS) to enable the simultaneous preconcentration, determination and removal of cadmium, cobalt and nickel ions from aqueous samples. In this procedure, a magnetic Pinus pinea bioadsorbent was synthesized and used as bio-adsorbent. The parameters such as solution pH, ultrasound time, analyte concentration and interfering ions were successfully optimized. All three metal ions were extracted within a mere 120 s at pH 6 and the extraction recovery values of the all three analytes were quantitative (>95%) under the optimal conditions. The adsorption processes of the metal ions were analyzed and adsorption of the metal ions were identified by Energy Dispersive X-Ray Mapping technique. A certified reference material was analyzed for the accuracy of the method. Finally, the developed method was applied for preconcentration and determination of the analytes in real water samples including natural spring water, natural mineral water and factory process water
Morphological and Thermal Characterization of Low-Cost Graphene Produced by Electrochemical Exfoliation Method
Get PDFThe low-cost and mass production of graphene has gained importance in recent years. The electrochemical exfoliation method, one of the graphene production methods, is an efficient technique used to obtain low-cost-effective and large quantities of graphene nanosheets. Exfoliation parameters affect the properties of exfoliated graphene nanosheets. In this study, graphene production is fabricated by the method of exfoliation using electrolyte and voltage parameters. For this, a pen tip was used instead of pure platinum, which is very expensive, at the cathode. The structural research was done by X-ray diffraction spectroscopy (XRD), Raman spectroscopy and Fourier Transform Infrared Spectrometer (F-TIR). Morphological analyses were carried out by Scanning Electron Microscopy (SEM). The number of layers and crystallite of graphene layers were estimated. The obtained results were compared with the results of the other similar studies. Analysis results show that low-cost multilayer graphene can be produced by the electrochemical exfoliation method with the electrical parameters
The effect of Web 2.0 tools supported games on achievement and attitude in primary school Turkish grammar teaching
Get PDFEğitim Bilimleri Enstitüsü, Temel Eğitim Ana Bilim Dalı, Sınıf Öğretmenliği Eğitimi Bilim DalıBu çalışmanın amacı Türkçe dil bilgisi öğretiminde web 2.0 araçları destekli oyunların öğrencilerin akademik başarısına ve Türkçe dersine ilişkin tutumlarına etkisini araştırmaktır. Çalışmada 4. Sınıf Türkçe dersi "Milli Mücadele ve Atatürk" ve "Kişisel Gelişim" temalarına yönelik hazırlanan oyunlar kullanılmıştır. Araştırmanın çalışma grubu; 2022-2023 eğitim öğretim yılının bahar döneminde Niğde il merkezinde bulunan bir devlet okulunda, 50 kişiden oluşan 4. sınıf öğrencilerinden oluşmaktadır. Araştırmada deneysel modellerden ön test- son test kontrol gruplu yarı deneysel desen kullanılmıştır. Araştırma deney ve kontrol grubu olmak üzere iki şubede gerçekleştirilmiştir. Deney grubunda web 2.0 araçları ile oluşturulmuş oyunlar, kontrol grubunda ise öğretim programı uygulanmıştır. Araştırma verileri araştırmacı tarafından geliştirilen " Türkçe Dersi Dil Bilgisi Akademik Başarı Testi" ile Acat tarafından geliştirilen "Türkçe Dersine İlişkin Tutum Ölçeği" ile toplanmıştır. Araştırmacı tarafından hazırlanan 22 soruluk başarı testinin KR-20 güvenirlik katsayısı .83 hesaplanmıştır. Elde edilen veriler SPSS paket programından yararlanılarak bilgisayar ortamında analiz edilmiştir. Araştırma sonucunda; Türkçe dil bilgisi öğretiminde web 2.0 araçları ile oluşturulmuş oyunların kullanılmasının deney grubu öğrencilerinin akademik başarı puanlarını ve Türkçe dersine ilişkin tutum puanlarını olumlu etkilediği belirlenmiştir. Öğrencilerin hem akademik başarılarını hem de Türkçe dersine ilişkin tutumlarını artırmıştır.The aim of this study is to investigate the effect of games supported by web 2.0 tools on students' academic achievement and attitudes towards Turkish language teaching.In the study, games prepared for the 4th grade Turkish lesson "National Struggle and Atatürk" and "Personal Development" themes were used. The study group of the research; In the spring semester of the 2022-2023 academic year, it consists of 4th grade students consisting of 50 students in a public school in the city center of Niğde. In the study, a quasi-experimental design with pretest-posttest control group was used. The research was conducted in two branches, experimental and control groups. Games created with web 2.0 tools were applied in the experimental group and the curriculum was applied in the control group. The research data were collected with the "Turkish Language Academic Achievement Test" developed by the researcher and the "Attitude Scale towards Turkish Lesson" developed by Acat. The KR-20 reliability coefficient of the 22-question achievement test prepared by the researcher was calculated as .83. The data obtained were analyzed in computer environment by using SPSS package program. As a result of the research; it was determined that the use of games created with web 2.0 tools in teaching Turkish grammar positively affected the academic achievement scores of the experimental group students and their attitude scores towards Turkish lesson. It increased both students' academic achievement and their attitudes towards Turkish lesson