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170423

VIII. Sebze Tarımı Sempozyumu (23-26 Haziran 2010 Van) Bildiri Kitabı

CEMALOĞLU, Nazmi

Serada organik domates yetiştiriciliğinde bitki besleme.

166718

Özel yetenekli öğrencilerin yaratıcı yazma beceri düzeylerinin incelenmesi
Investigating creative writing skills of gifted and talented students

Özcan, Bahadır

Bu araştırmada, Bilim ve Sanat Merkezinde (BİLSEM) öğrenim görmekte olan özel yetenekli öğrencilerin yaratıcı yazma beceri düzeylerinin cinsiyet ve yetenek alanı değişkenlerine göre incelenmesi amaçlanmıştır. Bu araştırma nedensel karşılaştırma türü bir çalışmadır. Araştırmanın çalışma grubunu BİLSEM’de öğrenim gören resim, müzik ve genel yetenek alanlarında özel yetenekli olduğu tespit edilen 85 öğrenci oluşturmaktadır. Veriler, öğrencilerden alınan yazılı anlatımların değerlendirilmesinde Yaratıcı Yazma Dereceli Puanlama Anahtarı (rubric) kullanılmıştır. Verilerin analizinde bağımsız gruplar için t-testi ve Kruskal Wallis-H testi kullanılmıştır. Araştırmanın sonucunda özel yetenekli erkek öğrencilerin, yaratıcı yazma düzeyleri kız öğrencilerden anlamlı düzeyde daha yüksektir. Ayrıca resi...

169658

Can Plant Extracts Be Used as an Alternative for Short- and/or Long-Term Storage of Semen in Some Animal Species?

Tuncer,, Pürhan Barbaros

Ex situ koruma, genetik kaynakların ve nesli tükenmekte olan kanatlıların korunmasında önemli bir yöntemdir. Gamet koruması için kanatlılarda tek yöntem spermanın dondurulmasıdır. Çünkü kanatlı yumurtaları oldukça hacimlidir ve bunların dondurularak saklanması için kullanılan kriyoprotektanların çözüm sonu uzaklaştırılması pek mümkün değildir. Son yirmi yılda, standart kanatlı spermasının don durma teknolojisini geliştirmek için birçok çalışma yapılmıştır. Farklı ırklara uyum sağlamak için birçok girişim ve yöntem araştırılmıştır. Bu bölümde, ilk olarak spermatozoanın yapısı ve kanatlı spermasının dondurulmasını etkileyen ana faktörlerden bahsedilmiştir. Nanopartiküller ve sperma sulandırıcılarına katılan nanopartiküllerin sperma dondurulabilirliği üzerine etkileri hakkında bilgi verilmiş...

169694

Enhancing low-temperature ethanol-selective catalytic reduction over Ag/TiO2-cordierite catalysts via cerium addition
Enhancing low-temperature ethanol-selective catalytic reduction

Resitoglu, Ibrahim Aslan

The purpose of this study is to investigate the NOx reduction activity of Ag/TiO2-Cordierite catalysts enhanced with cerium (Ce) under varying operational temperatures and engine loads. The aim is to improve the low-temperature activity of the catalyst in an ethanol-selective catalytic reduction system using real exhaust gases. During the catalyst production process, Ag and Ce were used as active components, TiO2 as the secondary support material, and cordierite as the primary carrier structure material. Catalysts with 1 wt%, 3 wt%, and 5 wt% Ce-doped Ag/TiO2/Cordierite were synthesized using the washcoating method and characterized through X-Ray Diffraction, Brunauer-Emmett-Teller analysis, and Scanning Electron Microscopy (SEM). Performance test results demonstrated that the NOx conversi...

169757

New phosphine-amino-alcohol tridentate ligands for ruthenium catalyzed asymmetric transfer hydrogenation of ketones

Altan, Orhan | Yılmaz, Mustafa Kemal

New phosphine-amino-alcohol tridentate ligands (3a-c) and six new ruthenium complexes (4a-c and 5a-c) were synthesized and characterized. Catalytic activities of the metal complexes were tested on aryl alkyl ketones. All of the substrates were converted to related sec-alcohols in excellent yields (up to 99%), but enantioselectivities were insufficient (up to 40% ee). Despite the catalytic performance of 5a-c complexes can be considered as better than 4a-c, actually the catalytic activity of the complexes has been differed according to substrate. The ketones with less positive carbonyl carbons tend to give S-configuration with 5a-c and R-configuration with 4a-c. The catalytic performance of the complexes was rationalized by means of DFT calculations.

169771

The effects of Fe2O3 based DOC and SCR catalyst on the exhaust emissions of diesel engines

Resitoglu, Ibrahim Aslan

The effects of Fe2O3 based DOCs (Diesel Oxidation Catalyst) and SCR (Selective Catalytic Reduction) catalysts on the exhaust emissions of diesel engine were investigated in this experimental study. The investigated catalysts, Al2O3 - TiO2/CeO2/Fe2O3 (ATCF) and Al2O3- Nb2O5/CeO2/Fe2O3 (ANCF), were produced with impregnation method and aged for 6 h at 600 degrees C. FE-SEM (Field Emission Scanning Electron Microscopy), XRD (X-Ray Diffraction), XRF (X-Ray Fluorescence) and BET (Brunauer-Emmett-Teller) Surface Area analyzes were carried out to determine the specifications of catalysts. The catalytic performances of the DOCs were tested for the oxidation of CO, HC, PM, NO while SCR catalysts were tested for SCR of NOx using NH3. An individual exhaust system was built up and mounted to the engin...

Makale2020Fuel 4 | 0 Erişime Kapalı
169772

Nanostructured Photocatalysts Chapter 15 - Black phosphorus-based photocatalysts for energy and environmental applications

Altan, Orhan

Photocatalysis using semiconductor materials to conduct chemical reactions more efficiently with the aid of sunlight irradiation is foreseen as a promising solution to combat the energy and environmental pollution crisis that the world is facing at present. Finding a suitable semiconductor material that harvests a large portion of the sunlight spectrum with high photocatalytic efficiency lies in the heart of photocatalysis. In this regard, black phosphorus (BP), a rising star two-dimensional (2D) semiconducting material, has recently been regarded as an abundant, nontoxic, metal-free, and cheap photocatalyst with a suitable bandgap and broad light absorption ability. In this chapter, after the introduction of the general properties and synthesis of BP, the photocatalytic efficiency of BP a...

169777

Boosting formic acid dehydrogenation via the design of a Z-scheme heterojunction photocatalyst: The case of graphitic carbon nitride/Ag/Ag3PO4-AgPd quaternary nanocomposites

Altan, Orhan

The development of an efficient, eco-friendly, practical, and selective way to decompose formic acid (FA) into H2 and CO2 is crucial for the utilization of FA as a chemical hydrogen storage material in hydrogen economy. In this regard, photocatalytic FA dehydrogenation attracts great attention owing to its potential to meet the above-mentioned requirements. Interestingly, there is no example of heterojunction photocatalyst that tunes the hole potential of the semiconductor, resulted in a better photocatalytic activity. We report herein for the first time the design and fabrication of a novel Z-scheme heterojunction photocatalyst for FA dehydrogenation, denoted as g-CN/Ag/Ag3PO4-AgPd comprising graphitic carbon nitride (g-CN) and Ag3PO4 semiconductors, Ag and AgPd alloy nanoparticles (NPs)....

Makale2021Applied Surface Science 2 | 0 Erişime Kapalı
169802

The influence of band bending phenomenon on photocatalytic Suzuki-Miyaura coupling reaction: The case of AgPd alloy nanoparticles supported on graphitic carbon nitride

Altan, Orhan

The development of solar-powered systems for applications other than energy, such as photocatalytic organic reactions, will benefit in the resolution of environmental issues while also lowering production costs. In this study, the photocatalytic activity of g-CN(G)-AgPd, which was prepared by synthesizing AgPd alloy nanoparticles (NPs) on g-CN, was investigated in the Suzuki-Miyaura coupling (SMC) reaction. The photocatalytic activity of g-CN(G)-AgPd in an ethanol/water mixture at ambient temperature was discovered to be among the highest ever recorded. Under vis-light illumination, g-CN(G)-AgPd converted all of the aryl iodides and most of the aryl bromides investigated to desired coupling products in 15 min with excellent isolated yields, and it was used at least five times without signi...

Makale2022Applied Surface Science 2 | 0 Erişime Kapalı
169804

A rare example of the in situ formation of palladium nanoparticles: The emergence of catalytically active palladium nanoparticles from Pd (II) phosphine complexes in the Suzuki–Miyaura coupling reaction

Altan, Orhan

Suzuki–Miyaura coupling (SMC) reactions are one of the most promising routes for carbon–carbon bond formation. It is believed that metal complexes, particularly palladium complexes, are the most effective catalysts for this purpose. However, the catalysis nature whether it is homogenous or heterogeneous is under debate. It is commonly believed that a homogenous catalysis pathway is responsible for the catalytic activity when the phosphine ligands are present in the structure due to the strong phosphorus-metal interactions. In this study, Pd (II) complexes of phosphino-benzaldoxime ligands were synthesized, characterized, and tested in SMC reactions. Interestingly, it was found that the catalytic activity increased by 11 times when the amount of catalyst was reduced by 10-fold and increased...

169807

The rational design of a graphitic carbon nitride-based dual S-scheme heterojunction with energy storage ability as a day/night photocatalyst for formic acid dehydrogenation

Altan, Orhan

Photocatalytic formic acid dehydrogenation (FAD) has been regarded as one of the most promising methods of producing H2 in a sustainable manner. In the photocatalytic FAD reaction, photogenerated holes play an important role in the reaction mechanism and thus in the efficiency of photocatalysts. However, the design of photocatalytic systems capable of generating high hole potential without compromising the reducing ability of the photocatalyst is extremely rare for the FAD reaction. In this respect, we report herein a novel and highly efficient heterojunction photocatalyst composed of 2D graphitic carbon nitride, 2D MnO2, 1D MnOOH, and 0D PdAg alloy nanoparticles, denoted as GCN/MnO2/MnOOH-PdAg, that can create high reduction and oxidation potentials via a dual S-scheme heterojunction. The...

169995

Estimation of soil liquefaction using artificial intelligence techniques: an extended comparison between machine and deep learning approaches

Şehmusoğlu, Eyyüp Hakan | Kurnaz, Talas Fikret | Erden, Caner

This study investigates the effectiveness of various deep learning (DL) algorithms in predicting soil liquefaction susceptibility. We explore a spectrum of algorithms, including machine learning models such as Support Vector Machines (SVMs), K-Nearest Neighbors (KNN), and Logistic Regression (LR), alongside DL architectures like Convolutional Neural Networks (CNNs), Long Short-Term Memory networks (LSTMs), Bidirectional LSTMs (BiLSTMs), and Gated Recurrent Units (GRUs). The performance of these algorithms is assessed using comprehensive metrics, including accuracy, precision, recall, F1-score, receiver operating characteristic (ROC) curve analysis, and area under the curve (AUC). Cross-entropy loss is employed as the loss function during model training to optimize the differentiation...

169996

An integrated SHAP-MCDM approach for slope stability prediction based on machine learning algorithms

Demir, Alparslan Serhat | Dağdeviren, Uğur | Kurnaz, Talas Fikret | Erden, Caner | Kökçam, Abdullah Hulusi

In machine learning (ML)-based slope stability prediction studies, feature importance results often vary across different algorithms, leading to inconsistent interpretations. This issue arises because the importance of features differs depending on the algorithm applied within the same study. To address this challenge, this study proposes a novel methodology for obtaining a final, unified ranking of features by combining the feature importance rankings of various ML algorithms using a Multi-Criteria Decision-Making (MCDM) technique. This approach ensures a consistent and reliable feature ranking derived from the results of successful ML models. Furthermore, the study demonstrates how performance indicators of ML algorithms can be translated into criterion weights within the MCDM f...

Makale2025Natural Hazards 3 | 0 Erişime Açık
170014

Development of Fe2O3 based catalysts to control pollutant emissions in diesel engines

Resitoglu, Ibrahim Aslan | Yıldırımcan, Saadet

Exhaust after treatment systems have become a necessity to eliminate pollutant emissions as required by standard. Nowadays, DOC and SCR are widely used after treatment technologies in diesel vehicles. In this experimental study carried on DOC and SCR systems, two different catalysts as Al2O3-TiO2/Fe2O3 and Al2O3-Pt/Fe2O3 were produced with impregnation method. The catalysts were characterized by Field Emission-Scanning Electron Microscope (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and Brauner-Emmett-Teller (BET). Each catalyst was tested as DOC and SCR in real working state to see the effect of catalyst on pollutant emissions in diesel engine. Results showed that the use catalysts as DOC led to significant decrease in CO, HC, NO and smoke emissions. The exhaust temperature...

Makale2017Fuel 0 | 0 Erişime Kapalı
170015

Hydrogen applications in selective catalytic reduction of NOx emissions from diesel engines

Resitoglu, Ibrahim Aslan

Diesel engines have been considered as a major source in nitrogen oxide (NOx) formation worldwide. The widespread use of diesel engines in consequence of their low fuel consumption, high durability and efficiency increases NOx emissions day by day. NOx emissions from diesel engines cause unavoidable damage on environment and people health. Although so many technologies such as exhaust gas recirculation (EGR), lean burn combustion, electronic controlling fuel injection systems, etc. have been developed to control NOx emissions from diesel engines, they couldn't meet the desired reduction in NOx emissions. In any case, Selective Catalytic Reduction (SCR) as one of the most promising aftertreatment-emission control technologies is an effective solution in restriction of NOx emissions. Th...

169293

Enhanced electrochemical sensing of nitrite ions in water samples using hydroxyapatite-zinc oxide nanocomposite modified carbon paste electrode

Turunç, Ersan | Binzet, Rıza

This study reports the green synthesis of a hydroxyapatite‑zinc oxide (HAp-ZnO) nanocomposite using Onosma mersinana leaf extract (OMLE) and its application as a highly sensitive electrochemical sensor for nitrite ion detection. The structural and surface characteristics of the synthesized nanomaterial were confirmed by XRD, which revealed crystalline phases corresponding to both HAp and ZnO; SEM analysis showed uniform morphology; EDX confirmed elemental composition; and XPS identified chemical states of Zn, O, Ca, C, and P, verifying successful ZnO doping. The HAp-ZnO nanocomposite was incorporated into a carbon paste electrode (CPE) to fabricate the CPE@HAp-ZnO100 sensor for the electrochemical detection of nitrite. The electrochemical behavior of nitrite on the CPE@HAp-ZnO100 electrode...

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