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Article Citation - WoS: 1Citation - Scopus: 1Chemical Composition Optimization and Isothermal Transformation of Δ-Transformation Plasticity Steel for the Third-Generation Advanced High-Strength Steel Grade(Wiley-v C H verlag Gmbh, 2024) Okur, Onur; Davut, Kemal; Palumbo, Gianfranco; Nalcaci, Burak; Guglielmi, Pasquale; Yalcin, Mustafa Alp; Erdogan, MehmetA new low-manganese transformation-induced plasticity steel is designed with optimized nickel content to achieve superior strength and ductility while minimizing the use of expensive nickel. The steel is optimized using JMatPro software, then cast, and hot rolled. To assess the effect of intercritical annealing on austenite (martensite at room temperature) volume fraction and carbon content, hot-rolled steel samples quenched from different annealing temperatures (680-1100 degrees C) are used. Additionally, hot-rolled steel coupons are intercritically annealed at about 50% austenite formation temperature (740 degrees C) and then subjected to isothermal treatments at 300-425 degrees C for varying times (10-90 min). After optimizing these treatments to maximize retained austenite (RA), tensile specimens are heat-treated first at 740 degrees C and then isothermally at 325 degrees C. Thermodynamic calculations suggest that aluminum combined with silicon may lead to the delta ferrite formation, and even minimal nickel content can stabilize a considerable amount of austenite. In the experimental studies, it is shown that lower-temperature bainitic holding enhances austenite stability by enriching the carbon content. Optimized two-stage heat treatments yield up to 25.8% RA, with a tensile strength of 867.2 MPa and elongation of 40.6%, achieving a strength-elongation product of 35.2 GPax%, surpassing the third-generation advanced high-strength steel grades minimum requirement of 30 GPax%.Article Citation - WoS: 41Citation - Scopus: 48Platinated Copper(3-Clip Complexes as Effective Dna-Cleaving and Cytotoxic Agents(Wiley-v C H verlag Gmbh, 2008) Ozalp-Yaman, Seniz; de Hoog, Paul; Amadei, Giulio; Pitie, Marguerite; Gamez, Patrick; Dewelle, Janique; Reedijk, JanThe synthesis and biological activity of three heteronuclear platinum-copper complexes based on 3-Clip-Phen are reported. These rigid complexes have been designed to alter the intrinsic mechanism of action of both the platinum moiety and the Cu(3-Clip-Phen) unit. The platinum centers of two of these complexes are coordinated to a 3-Clip-Phen moiety, an ammine ligand and two chlorides, which are either cis or trans to each other. The third complex comprises two 3-Clip-Phen units and two chloride ligands bound in a trans fashion to the platinum ion. DNA-cleavage experiments show that the complexes are highly efficient nuclease agents. In addition, a markedly difference in their aptitude to perform direct double-strand cleavage is observed, which appears to be strongly related to the ability of the platinum unit to coordinate to DNA. Indeed, complex 6 is unable to coordinate to DNA, which is reflected by its incapability to carry out double-strand breaks. Nonetheless, this complex exhibits efficient DNA-cleavage activity, and its cytotoxicity is high for several cell lines. Complex 6 shows better antiproliferate activity than both cisplatin and Cu(3-Clip-Phen) toward most cancer cell lines. Furthermore, the cytotoxicity observed for 1 is for most cell lines close to that of cisplatin, or even better. Cu(3-Clip-Phen) induces very low cytotoxic effects, but a marked migratory activity. Complex 6 presents DNA-cleavage properties comparable to the one of Cu(3-Clip-Phen), but it does not show any migratory activity. Interestingly, both Cu(3-Clip-Phen) and 6 induces vacuolisation processes in the cell in contrast to complex 1 and cisplatin. Thus, the four complexes cisplatin tested, Cu(3-Clip-Phen), I and 6 stimulate different cellular responses.Article Citation - WoS: 75Citation - Scopus: 80Unique Ligand-Based Oxidative Dna Cleavage by Zinc(ii) Complexes of Hpyramol and Hpyrimol(Wiley-v C H verlag Gmbh, 2007) Maheswari, Palanisamy Uma; Barends, Sharief; Oezalp-Yaman, Seniz; de Hoog, Paul; Casellas, Helene; Teat, Simon J.; Reedijk, JanThe zinc(II) complexes reported here have been synthesised from the ligand 4-methyl-2-N-(2-pyridylmethyl)aminophenol (Hpyramol) with chloride or acetate counterions. All the five complexes have been structurally characterised, and the crystal structures reveal that the ligand Hpyramol gradually undergoes an oxidative dehydrogenation to form the ligand 4-methyl-2-N-(2-pyridylmethylene)aminophenol (Hpyrimol), upon coordination to Zn-II. All the five complexes cleave the phi X174 phage DNA oxidatively and the complexes with fully dehydrogenated pyrimol ligands were found to be more efficient than the complexes with non-dehydrogenated Hpyramol ligands. The DNA cleavage is suggested to be ligand-based, whereas the pure ligands alone do not cleave DNA. The DNA cleavage is strongly suggested to be oxidative, possibly due to the involvement of a non-diffusible phenoxyl radical mechanism. ne enzymatic religation experiments and DNA cleavage in the presence of different radical scavengers further support the oxidative DNA cleavage by the zinc(II) complexes.Article Citation - WoS: 2Citation - Scopus: 2Investigation of Tungsten-Based Seleno-Chevrel Compounds With Different Compositions for Efficient Water Splitting(Wiley-v C H verlag Gmbh, 2023) Dag, Tugce Sevinc; Surucu, Gokhan; Gencer, Aysenur; Surucu, Ozge; Ozel, Faruk; Ciftci, YaseminThis study investigates the photocatalytic water splitting performance for NixW6Se8(x=1,2,3,4)${\mathrm{N}}{{\mathrm{i}}_{\mathrm{x}}}{{\mathrm{W}}_6}{\mathrm{S}}{{\mathrm{e}}_8}\;( {x = 1, 2, 3, 4} )$ Chevrel phases with the chemical formula M(x)Mo(6)Ch(8), where M is a metal and Ch is a chalcogen, with x being 0, 1, 2, 3, or 4. Density Functional Theory (DFT) is used to study the NixW6Se8(x=1,2,3,4)${\mathrm{N}}{{\mathrm{i}}_{\mathrm{x}}}{{\mathrm{W}}_6}{\mathrm{S}}{{\mathrm{e}}_8}{\mathrm{\;}}( {x = 1, 2, 3, 4} )$ Chevrel phases, which includes earth-abundant elements for this specific study as an essential consideration for photocatalytic water splitting. The electronic properties are calculated for the NiW6Se8 and Ni2W6Se8 compounds with thermodynamical, mechanical, and dynamic stabilities. For photocatalytic water splitting, the band gaps below 1.23 eV are excluded, and the conduction and valence band levels are determined to examine the reduction and oxidation potentials for efficient photocatalytic water-splitting materials. An examination of the selected band gaps, along with the conduction and valence band levels, reveals that NiW6Se8 is suitable for both reduction and oxidation reactions; whereas, Ni2W6Se8 is a convenient material only for the reduction reaction. This is the first attempt, as far as the literature reveals, to study Chevrel phases in detail and to identify a suitable compound for photocatalytic water splitting.Article Citation - WoS: 11Citation - Scopus: 13The Convergence of q-bernstein Polynomials (0 < q < 1) in the Complex Plane(Wiley-v C H verlag Gmbh, 2009) Ostrovska, SofiyaThe paper focuses at the estimates for the rate of convergence of the q-Bernstein polynomials (0 < q < 1) in the complex plane. In particular, a generalization of previously known results on the possibility of analytic continuation of the limit function and an elaboration of the theorem by Wang and Meng is presented. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimArticle Citation - WoS: 11Citation - Scopus: 14Schwarz Problem for Higher-Order Complex Partial Differential Equations in the Upper Half Plane(Wiley-v C H verlag Gmbh, 2019) Aksoy, Umit; Begehr, Heinrich; Celebi, A. OkayLinear and nonlinear elliptic complex partial differential equations of higher-order are considered under Schwarz conditions in the upper-half plane, Firstly, using the integral representations for the solutions of the inhomogeneous polyanalytic equation with Schvvarz conditions, a class of integral operators is introduced together with some of their properties. Then, these operators are used to transform the problem for linear equations into singular integral equations. In the case of nonlinear equations such a transformation yields a system of integro-differential equations. Existence of the solutions of the relevant boundary value problems for linear and nonlinear equations are discussed via Fredholm theory and fixed point theorems, respectively.Article Citation - WoS: 13Citation - Scopus: 15Stability Criterion for Second Order Linear Impulsive Differential Equations With Periodic Coefficients(Wiley-v C H verlag Gmbh, 2008) Guseinov, G. Sh.; Zafer, A.In this paper we obtain instability and stability criteria for second order linear impulsive differential equations with periodic coefficients. Further, a Lyapunov type inequality is also established. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Article Citation - WoS: 2Citation - Scopus: 1Direct Detection of Viral Infections From Swab Samples by Probe-Gated Silica Nanoparticle-Based Lateral Flow Assay(Wiley-v C H verlag Gmbh, 2024) Durdabak, Dilara Buse; Dogan, Soner; Tekol, Serap Demir; Celik, Caner; Ozalp, Veli Cengiz; Tuna, Bilge GuvencPoint-of-care diagnosis is crucial to control the spreading of viral infections. Here, universal-modifiable probe-gated silica nanoparticles (SNPs) based lateral flow assay (LFA) is developed in the interest of the rapid and early detection of viral infections. The most superior advantage of the rapid assay is its utility in detecting various sides of the virus directly from the human swab samples and its adaptability to detect various types of viruses. For this purpose, a high concentration of fluorescein and rhodamine B as a reporting material was loaded into SNPs with excellent loading capacity and measured using standard curve, 4.19 mu mol & sdot; g-1 and 1.23 mu mol & sdot; g-1, respectively. As a model organism, severe acute respiratory syndrome coronavirus-2 (CoV-2) infections were selected by targeting its nonstructural (NSP9, NSP12) and envelope (E) genes as target sites of the virus. We showed that NSP12-gated SNPs-based LFA significantly outperformed detection of viral infection in 15 minutes from 0.73 pg & sdot; mL-1 synthetic viral solution and with a dilution of 1 : 103 of unprocessed human samples with an increasing test line intensity compared to steady state (n=12). Compared to the RT-qPCR method, the sensitivity, specificity, and accuracy of NSP12-gated SNPs were calculated as 100 %, 83 %, and 92 %, respectively. Finally, this modifiable nanoparticle system is a high-performance sensing technique that could take advantage of upcoming point-of-care testing markets for viral infection detections. Here, universal-modifiable probe-gated silica nanoparticles (SNPs) based lateral flow assay (LFA) is developed in the interest of the rapid and early detection of viral infections. The most superior advantage of the rapid assay is its utility in detecting various sides of the virus directly from the human swab samples and its adaptability to detect various types of viruses. The NSP12, NSP9, and E gene targets of CoV-2 were used as detection targets.imageArticle Citation - WoS: 30Citation - Scopus: 29A New, Highly Conductive, Lithium Salt/Nonionic Surfactant, Lyotropic Liquid-Crystalline Mesophase and Its Application(Wiley-v C H verlag Gmbh, 2012) Albayrak, Cemal; Cihaner, Atilla; Dag, Omer[No Abstract Available]Article Citation - WoS: 3Citation - Scopus: 2Establishing the nimo6se8< Chevrel Phase as a Promising Material Using Dft(Wiley-v C H verlag Gmbh, 2024) Surucu, Gokhan; Surucu, Ozge; Usanmaz, Demet; Oezel, Faruk; Gencer, AysenurIn this study, the NiMo6Se8 Chevrel phase is analyzed using Density Functional Theory (DFT) and the Vienna Ab-initio Simulation Package (VASP). The analysis focuses on the phase's structural, electrical, and mechanical characteristics to fill gaps in the current literature. The presence of a rhombohedral crystal structure confirms its thermodynamic stability, as indicated by a negative formation enthalpy, which suggests that it can be synthesized under favorable conditions. The electronic properties of the phase are analyzed, indicating that it exhibits semiconductor characteristics with a bandgap of 1.07 eV. This makes it appropriate for various technological applications. The estimated elastic constants provide an indication of mechanical strength and flexibility, with a noticeable presence of anisotropic elasticity. The confirmation of dynamical stability is achieved by analyzing the phonon dispersion curve, which reveals the absence of any negative frequencies. Furthermore, the material has a low thermal conductivity, increasing its suitability for thermoelectric applications. The analysis emphasizes the versatile capabilities of the NiMo6Se8 Chevrel phase, especially in thermoelectric and energy storage applications, showcasing its promising potential for future technological implementation.
