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  • Öğe
    Synthesis, crystal structure, DFT studies, Hirshfeld surface analysis and drug delivery performance of bis(2-chloro-4,6-diaminopyrimidine)copper(II)-dichloride
    (Elsevier, 2021) Yağcı, Nermin Kahveci; Kansız, Sevgi; Özcandan, Eda
    The new single crystal, bis(2-chloro-4,6-diaminopyrimidine)-copper(II)-dichloride [CDPCD] compound was synthesized. The crystal structure of the compound was solved by the single crystal X-ray diffraction method. CDPCD has a = 6.3334(9) angstrom, b = 6.9914 (10) angstrom, c = 8.9901(12) angstrom, alpha = 78.127(11) degrees, beta = 86.853(11) degrees, gamma = 67.307(10)degrees and Z = 1 parameters and is crystallized in the space group P-1 in the triclinic crystal system. Complete vibration assignments of CDPCD in gas phase and experimental frequencies are reported together with the scaled force constants. The optimized geometric parameters and frequency values were theoretically calculated using DFT/B3LYP method with LANL2DZ basis set. The XRD single crystal measurement parameters are good agreed with the optimized parameters. Molecular orbital surfaces and molecular electrostatic potential properties were measured at B3LYP/LANL2DZ level. Hirshfeld surface and fingerprint drawings were obtained to explain the intermolecular interactions of the crystal structure. The most important contributions for the crystal packing are from Cl center dot center dot center dot H/H center dot center dot center dot Cl (38.7%), H center dot center dot center dot H (17.9%) and N center dot center dot center dot H/H center dot center dot center dot N (14.8%) interactions. In addition, the molecule was tested by MTT test to determine the apoptosis and necrosis by cytotoxicity and double staining method. For the MTT test [MTT: (3,4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide], the tetrazolium salt was used. In different percentages of the compound, apoptotic necrotic index ratios of L929 fibroblasts and MCF-7 cells decreased. Bilateral staining method was used to evaluate the cells that had undergone apoptosis and necrosis of FITC (480-520nm wavelength). Apoptotic and necrotic index results of L929 fibroblasts and MCF-7 cells decreased as the amount of concentration decreased. (C) 2021 Elsevier B.V. All rights reserved.
  • Öğe
    Refinement of fundamental characteristic properties with homovalent Er/Y partial replacement of YBa2Cu3O7-y ceramic matrix
    (Elsevier Science Sa, 2021) Erdem, Ümit; Turkoz, Mustafa B.; Yıldırım, Gürcan; Zalaoğlu, Yusuf; Nezir, Saffet
    In the current work, the effect of partial substitution of Er-sites for the Y-sites in the bulk YBa2Cu3O7-y (YBCO) crystal system on the fundamental superconducting, electrical, crystallinity and structural morphology features is examined together with the reasons by means of powder X-ray diffraction (XRD), temperature-dependent electrical resistivity (rho-T), scanning electron microscopy (SEM), electron dispersive X-ray (EDX) investigations and deduced calculation parameters. All the experimental test results show that the erbium impurities are suc-cessfully substituted by the yttrium sites in the bulk Y-123 crystal system, confirmed by sensitively the EDX and rho-T measurement results. Moreover, it is found that all the fundamental characteristic quantities improve with the increment in the Er/Y partial substitution level up to the value of x = 0.03 beyond which the features tend to degrade dramatically. In this respect, the bulk Y1-xErxBa2Cu3O7-y ceramic compound prepared within the molar ratio of x = 0.03 crystallizes in the orthorhombic space group P-4/ mmm with a little distortion due to the refinement in the crystallinity quality, crystallite growth, oxygen ordering degree, scattering mechanism, intra and intergrain boundary couplings, grain alignment distributions and orientations. The XRD results show that the optimum erbium content enables to develop seriously the fundamental crystallographic features (lattice strain, lattice cell constants, crystallite size distribution, dislocation density ratio, oxygen concentrations in the unit cells) of Y-123 crystal structure. However, the excess Er/Y substitution leads to enhance considerably the systematic structural problems and inhomogeneous distribution of strains (formed by the structural defects) in the YBCO crystal structure. Thus, the phase transition from orthorhombic to tetragonal (structural O-T transition) crystal structure is observed. In fact, the XRD result displays that the trivalent Er3+ particles may partially be replaced by the divalent Cu2+ host atoms in the bulk Y-123 crystal structure after the critic substitution level of x = 0.03. The optimum Er concentration causes to form more thermodynamically activated super-electrons in the homogeneous superconducting cluster percentages in the paths due to the induced polaronic effect, and accordingly the intrinsic overdoped nature of Y-123 ceramic system transits into optimally doped state. Similarly, the erbium ions enable to increase the mobile hole carrier concentration and homogeneities in the oxidation state of superconducting grains. Namely, the amplitude of pair wave function (Psi=Psi(0)e(-i phi)) is strength enough to form bipolarons in the polarizable lattices and localize of densities of electronic states (DOS) at Fermi level. SEM investigations picture that the surface morphology view and crystallinity quality develop remarkably with the increment in the erbium content up to the critical dopant level of x = 0.03 where the sample exhibits the best grain alignment orientations, densest and smoothest surface morphology with the combination of lowest porous and largest particle distributions well linked each other. All in all, this comprehensive work based on the analysis of Er/Y partial replacement mechanism along the YBa2Cu3O7- y ceramic matrix may open up a newly/novel and feasible area for the advanced engineering, heavy-industrial technology and large-scale applications of type-II superconducting materials. (C) 2021 Elsevier B.V. All rights reserved.
  • Öğe
    Re-examination of β-decay in Hg, Pb and PoIsotopes
    (Iop Publishing Ltd, 2023) Nabi, Jameel-Un; Bayram, Tuncay; Riaz, Muhammad; Ullah, Asim; Hayder, Anes; Şentürk, Şevki; Böyükata, Mahmut
    This study re-examines the effect of nuclear deformation on the calculated Gamow-Teller (GT) strength distributions of neutron-deficient (Hg178-192, Pb185-194 and Po196-206) nuclei. The nuclear ground state properties and shape parameters were calculated using the Relativistic Mean Field model. Three different density-dependent interactions ((DC)-C-3, DD-ME2 and DD-PC1) were used in the calculation. Estimated shape parameters were later used within the framework of deformed proton-neutron quasi-random phase approximations model, with a separable interaction, to calculate the GT strength distributions, half-lives and branching ratios for these neutron-deficient isotopes. It was concluded that half-lives and GT strength distributions vary considerably with change in shape parameter.
  • Öğe
    Re-examination of nuclear structure properties and shape co-existence of nuclei around A ∼ 70
    (Elsevier, 2024) Nabi, Jameel-Un; Bayram, Tuncay; Böyükata, Mahmut; Ullah, Asim; Hayder, Anes; Naqvi, Syeda Zainab
    We re-examine the nuclear structure properties of waiting point nuclei around A similar to 70 using the interacting boson model-1 (IBM-1) and the relativistic mean field (RMF) model. Effective density-dependent meson-exchange functional (DD-ME2) and density-dependent point-coupling functional (DD-PC1) were used for the RMF calculations. We calculated the energy levels, the geometric shapes, binding and separation energies of nucleons and quadrupole deformation parameters (beta 2). The shape co-existence phenomena in A similar to 70 nuclei (Se-68, Se-70, Br-70, Kr-70, Kr-72, Kr-74, Rb-74 and Sr-74) was later investigated. Spherical and deformed shapes of the selected waiting point nuclei were computed using the IBM-1 and RMF models, respectively. The proton-neutron quasiparticle random phase approximation (pn-QRPA) model was used to calculate beta-decay properties (Gamow-Teller strength distributions, beta-decay half-lives and branching ratios) of selected nuclei as a function of beta 2. The results revealed a significant variation in calculated half-lives and Gamow-Teller strength distributions as the shape parameter was changed. The beta 2 computed via DD-ME2 functional resulted in half-lives in best agreement with the measured data.
  • Öğe
    Can Stable MoS2 Monolayers and Multilayers Be Constituted in the Biphenylene Network?
    (Amer Chemical Soc, 2023) Gorkan, Taylan; Demirci, Salih; V. Barth, Johannes; Aktürk, Ethem; Çıracı, Salim
    Based on the first-principles calculations, we predict that the well-known 2H-MoS2 monolayer of the trigonal prismatic phase appearing in a hexagonal network can also constitute another stable phase in the biphenylene network (B-MoS2). It consists of the connected octagon, hexagon and square rings and hence maintains the same numbers of neighbors of the constituent atoms, but its bonds between transition metal and chalcogen atoms are deformed to construct a direct but narrow band gap semiconductor with directional electronic conduction and optical properties with strong absorption in the near-infrared region. It has softer mechanical properties and site specific chemical activities of the same kind of constituent atoms. In the same way, vacancies of different chalcogen atoms in the cell attain different defect states in the band gap. This phase can remain stable above the room temperature and has a cohesive energy comparable to all the other 2D phases of the same compound. In fact, transitions from the 2H-phase to the B-phase can be possible. The B-phase can form multilayers and also a metallic 3D layered, van der Waals crystal with weak interlayer coupling. The narrow band gap of the monolayer is reduced in the bilayer but diminishes in multilayers and 3D layered crystals to change the semiconductor to a metal. Even more interesting is that B-MoS2 is versatile for the modulation of the band gap, even for the metal-insulator transition under applied strains.
  • Öğe
    Sınıf Öğretmeni Adaylarının Fen ve Teknoloji Laboratuvarında Kullanılan Deney Türlerinin Motivasyon ve Kavramalarına Etkisiyle İlgili Görüşleri
    (2019) Aydın, Nilgün; Aydın, Abdullah
    Fen deneyleri, yapılış şekillerine, amaçlarına ve yapılış zamanına göre üç başlık altında toplanabilir. Bu araştırmanın amacı, sınıf öğretmeni adaylarının fen ve teknoloji laboratuvarı derslerinde kullanılan deney türlerinin motivasyonlarını ve kavramalarını nasıl etkilediğiyle ilgili görüşlerinin belirlenmesidir. Bu amaçla araştırmada olgubilim (fenomenoloji) deseni kullanılmıştır. Çalışma grubunu bir devlet üniversitesinin, Eğitim Fakültesi, Sınıf Öğretmenliği Anabilim Dalı’nda 2017-2018 eğitim-öğretim yılı bahar döneminde 2.sınıfta öğrenim gören 52 öğretmen adayı oluşturmaktadır. Verilerin elde edilmesinde 4 tane açık uçlu sorudan oluşan yarı yapılandırılmış görüşme formu kullanılmıştır. Bulgulara göre çalışma grubundaki öğretmen adaylarının %48,08’i, yapılış şekline göre hem gösteri hem de grup deneylerinin, %17,3’ü tamamen grup deneylerinin, %28,8’i tamamen gösteri deneylerinin, %5,7’si de bireysel deney yapılması yönünde görüş bildirmişlerdir. Öğretmen adaylarının %59,6’sının yapılış amacına göre kapalı uçlu deneyleri, %19,23’ünün açık uçlu deneyleri, %17,3’ünün hem kapalı uçlu hem de açık uçlu deney türünü %3,8’inin de hipotez test etme deneyini tercih ettikleri görülmüştür. Araştırmanın sonuçlarına göre, öğretmen adaylarının farklı deney yapma türlerini tercih ettikleri ve bu tercihleri doğrultusunda deneyler yapıldığında motivasyon ve kavramalarının daha olumlu etkileneceği yönünde görüş bildirdikleri görülmüştür.
  • Öğe
    Physical Properties of Martensitic Phase Transformations in Fe - 18.79%Mn-4.53%Ni Alloys
    (2016) Türk, Dilek; Yağcı, Nermin Kahveci
    Bu çalışmada, Fe-%18,79Mn-%4,53Ni alaşımında termal etki ile oluşturulan martensitik faz dönüşümlerinin kristalografik ve manyetik özellikleri araştırıldı. Taramalı Elektron Mikroskobu (SEM) ile termal etkili martensitelerin mikroyapıları incelendi. Mikroyapı incelemelerinde, termal etkili martensite yapı miktarının uygulanan sıcaklık derecelerinin artması ile arttığı gözlendi. Austenite faz içerisinde oluşan termal etkili martensite fazın hacim yüzdeleri Mössbauer Spektrometresi tekniği yoluyla belirlendi. X-ışını tekniği ile örgü parametrelerinde meydana gelen değişimler tespit edildi
  • Öğe
    Hydroxyapatite-based nanoparticles as a coating material for the dentine surface: An antibacterial and toxicological effect
    (ELSEVIER SCI LTD, 2020) Erdem, Umit; Dogan, Mustafa; Metin, Aysegul U.; Baglar, Serdar; Turkoz, Mustafa B.; Turk, Mustafa; Nezir, Saffet
    In this study, nano sized hydroxyapatite (nHAp) and Ag(I) doped hydroxyapatite (Ag-nHAp) particles were synthesized by the precipitation method and used as a coating material for remineralization on caries-affected dentine samples. Characterization studies of both the synthesized hydroxyapatite-based particles and the coated dentine samples were performed using instrumental techniques such as SEM and FFIR, and then toxicity and antibacterial properties were also evaluated. It was observed that dentine samples were effectively coated by both nHAp and Ag center dot nHAp particles which have no toxic effects. Furthermore, the costing of nano-hydroxyapatite on dentine samples positively contributed to the viability of L929 fibroblast cells and also provided an antibacterial effect against to bacteria such as S. mutants, C. albicans and E. coli bacteria that are most frequently caused caries in the teeth. While all type of bacteria was eliminated by the nHAp coated dentine samples at 24th, Ag-nHAp coated dentine samples removed to all bacteria type at 1st.
  • Öğe
    Temperature, strain and charge mediated multiple and dynamical phase changes of selenium and tellurium
    (ROYAL SOC CHEMISTRY, 2020) Demirci, Salih; Gürel, Hikmet Hakan; Jahangirov, Seymur; Çıracı, Salim
    Semiconducting selenium and tellurium in their 3D bulk trigonal structures consist of parallel and weakly interacting helical chains of atoms and display a number of peculiarities. We predict that thermal excitations, 2D compressive strain and excess charge of positive and negative polarity mediate metal-insulator transitions by transforming these semiconductors into different metallic crystal structures. When heated to high temperature, or compressed, or charged positively, they change into a simple cubic structure with metallic bands, which is very rare among elemental crystals. When charged negatively, they transform first into body-centered tetragonal and subsequently into the body-centered orthorhombic structures with increasing negative charging. These two new structures stabilized by excess electrons also have overlapping metallic bands and quasi 2D and 1D substructures of lower dimensionality. Since the external charging of crystals can be achieved through their surfaces, the effects of charging on 2D structures of selenium and tellurium are also investigated. Similar structural transformations have been mediated also in 2D nanosheets and free-standing monolayers of these elements. These phase changes assisted by phonons are dynamical, reversible and tunable; the resulting metal-insulator transitions can occur within very short time intervals and may offer important device applications.
  • Öğe
    Electronic, Elastic, Vibrational and Thermodynamic Properties of HfIrX (X = As, Sb and Bi) Compounds: Insights from DFT-Based Computer Simulation
    (SPRINGER, 2020) Arikan, Nihat; Dikici Yildiz, Gokcen; Yildiz, Yasin Gokturk; Iyigor, Ahmet
    Ab-initio calculations were performed to reveal and thoroughly understand the structural, electronic, elastic, thermodynamic and vibrational properties of HfIrX (X = As, Sb and Bi) compounds in the C1(b) phase. Basic physical characteristics, such as bulk modulus, pressure derivative of bulk modulus, anisotropy factor, shear modulus, Poisson's ratio, Cauchy pressure, elastic constants and Young's modulus were obtained and some of them were compared with those in the literature. Electronic band structure, the density of states and phonon dispersion curves were obtained and compared with current theoretical calculations. It was concluded according to current band structure calculations that the HfIrAs and HfIrBi compounds showed semimetal characteristics, while the HfIrSb compound behaves as a semiconductor. It was determined based on phonon calculations that all three compounds were dynamically stable. Various thermodynamic properties, such as heat capacity, thermal expansion coefficient values and Gruneisen parameter were calculated under constant volume and constant pressure by using Gibbs2 code within the Quasi-harmonic approach, and these results are discussed.
  • Öğe
    Intersection Magnetization and Temperature Revealed by FCC-FCT Phase Transformation in the FePd Binary Alloy System
    (SPRINGER, 2020) Yildiz, Gokcen Dikici
    This study investigated the fcc-fct phase transformation effect on the magnetic properties of the FePd alloy system by means of the effective field theory (EFT) developed by Kaneyoshi (1993). We determined the thermal magnetization loop and magnetic hysteresis loop of fcc-FePd and fct-FePd for both the ferromagnetic (FM) and antiferromagnetic (AFM) case. We found that the FM fcc-FePd and fct-FePd have a single thermal magnetization area, whereas AFM fcc-FePd and fct-FePd have binary thermal magnetization area. In the AFM case, the magnetization curves for fcc-FePd and fct-FePd had an intersection temperature point (Ti = 1.33 at H = 0). At Ti, the magnetization value of the fcc-FePd and fct-FePd was almost the same (Mi = 0.59) and we call this magnetization the intersection magnetization. However, the magnetic hysteresis loop area of the fcc-FePd was higher than that of the fct-FePd for both the FM and AFM case. Fcc-fct phase transformation has a strong effect on the FM and AFM properties of the FePd binary alloy system.
  • Öğe
    Monolayer diboron dinitride: Direct band-gap semiconductor with high absorption in the visible range
    (AMER PHYSICAL SOC, 2020) Demirci, Salih; Rad, Soheil Ershad; Kazak, Sahmurat; Nezir, Saffet; Jahangirov, Seymur
    We predict a two-dimensional monolayer polymorph of boron nitride in an orthorhombic structure (o-B2N2) using first-principles calculations. Structural optimization, phonon dispersion, and molecular dynamics calculations show that o-B2N2 is thermally and dynamically stable. o-B2N2 is a semiconductor with a direct band gap of 1.70 eV according to calculations based on hybrid functionals. The structure has high optical absorption in the visible range in the armchair direction while low absorption in the zigzag direction. This anisotropy is also present in electronic and mechanical properties. The in-plane stiffness of o-B2N2 is very close to that of hexagonal boron nitride. The diatomic building blocks of this structure hint at its possible synthesis from precursors having B-B and N-N bonds.
  • Öğe
    Focusing-free impedimetric differentiation of red blood cells and leukemia cells: A system optimization
    (ELSEVIER SCIENCE SA, 2020) Bilican, Ismail; Guler, Mustafa Tahsin; Serhatlioglu, Murat; Kirindi, Talip; Elbuken, Caglar
    A focusing-free microfluidic impedimetric cell detection system is developed. The effect of the channel dimensions, solution conductivity, excitation voltage, and particle size on impedimetric signal outputs were optimized to increase the sensitivity of the system. Conventional microfabrication techniques were adapted to obtain low height, resealable microchannels. The geometry optimization was performed by a combination of analytical, numerical and experimental approaches. The results demonstrate that reliable impedimetric particle differentiation can be achieved without any labeling or particle focusing. The system parameters were studied and rule-of-thumb design criteria were provided. Finally, using the developed system, red blood cells and leukemia cells were experimentally detected and differentiated. Thanks to its simplicity, the focusing-free cell differentiation system may find applications in several cellular diagnostic uses.
  • Öğe
    Investigation of the Mechanical, Electronic and Phonon Properties of X2ScAl (X = Ir, Os, and Pt) Heusler Compounds
    (KOREAN PHYSICAL SOC, 2020) Arikan, Nihat; Ocak, Hamza Yasar; Yildiz, Gokcen Dikici; Yildiz, Yasin Gokturk; Unal, Rahmi
    In the present study, the second-order elastic constants and the electronic band structures of the X2ScAl (x= Ir, Os, and Pt) compounds crystallized in the L2(1)phase were calculated separately by using theab-initiodensity functional theory. According to the results for the second-order elastic constants, these compounds met the Born mechanical stability criteria. Also, according to the Pugh criteria, they were found to have a ductile structure and to show anisotropic behavior. The microhardneses of the compounds were between 2 and 14 GPa, and the highest hardness was found in the Ir2ScAl (14.290 GPa) compound. In addition, the energy band structures of these compounds were calculated, and the crystals were found to have a metallic bond structure. All the computed data were compared with previously calculated results obtained with different methods. According to the findings obtained in the present study, in terms of its mechanical and electronic behaviors, Ir2ScAl was found to have better physical properties than Os2ScAl and Pt2ScAl. The phonon dispersion curves and their corresponding total and projected densities of states were investigated for the first time by using a linear-response approach in the context of density functional perturbation theory. The frequencies of the optical phonon modes of all compounds at the Gamma point were 4.767, 7.504 and 9.271 THz for Ir2ScAl, 2.761, 7.985 and 9.184 THz for Os2ScAl and 2.012, 5.6952 and 8.118 THz for Pt2ScAl. The heat capacityC(v)at constant volume versus temperature was calculated using a quasi-harmonic approach and the results are discussed.
  • Öğe
    Crystal structure, Hirshfeld surface analysis and DFT studies of (E)-4-methyl-2-{[(4-methylphenyl)-imino]methyl}phenol
    (INT UNION CRYSTALLOGRAPHY, 2020) Yagci, Nermin Kahveci; Faizi, Md Serajul Haque; Aydin, Alev Sema; Dege, Necmi; Dogan, Onur Erman; Agar, Erbil; Mashrai, Ashraf
    In the title compound, C15H15NO, the configuration of the C=N bond of the Schiff base is E, and an intramolecular O-H center dot center dot center dot N hydrogen bond is observed, forming an intramolecular S(6) ring motif. The phenol ring is inclined by 45.73 (2)degrees from the plane of the aniline ring. In the crystal, molecules are linked along the b axis by O-H center dot center dot center dot N and C-H center dot center dot center dot O hydrogen bonds, forming polymeric chains. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the packing arrangement are from H center dot center dot center dot H (56.9%) and H center dot center dot center dot C/C center dot center dot center dot H (31.2%) interactions. The density functional theory (DFT) optimized structure at the B3LYP/ 6-311 G(d,p) level is compared with the experimentally determined molecular structure, and the HOMO-LUMO energy gap is provided. The crystal studied was refined as an inversion twin.
  • Öğe
    Two dimensional ruthenium carbide: structural and electronic features
    (ROYAL SOC CHEMISTRY, 2020) Görkan, Taylan; Demirci, Salih; Jahangirov, S.; Gokoglu, Gökhan; Aktürk, Ethem
    The design and realization of novel 2D materials and their functionalities have been a focus of research inspired by the successful synthesis of graphene and many other 2D materials. In this study, in view of first principles calculations, we predict a novel 2D material ruthenium carbide (RuC) in graphene-like honeycomb hexagonal lattice with planar geometry. Phonon dispersion spectra display a dynamically stable structure. Comprehensive molecular dynamics calculations confirm the stability of the structure up to high temperatures as approximate to 1000 K. The system is a narrow gap semiconductor with a band gap of 53 meV (345 meV) due to GGA-PBE (HSE) calculations. Band gap exhibits significant changes by applied strain. Elastic and optical properties of the system are examined in monolayer form. RuC/RuC bilayer, RuC/graphene and RuC/h-BN heterostructures are also investigated. By calculating the phonon dispersion it is verified that RuC bilayer is the most stable in AA type-stacking configuration where Ru and C atoms of both layers have identical lateral coordinates. The effects of atomic substitutions on electronic band structures, acting as p-type and n-type doping, are revealed. A novel 3D RuCLi structure is also predicted to be stable and the isolation of its monolayer forms are discussed. Ruthenium carbide, as a 2D material which is dynamically and thermally stable, holds promise for applications in nanoelectronics.
  • Öğe
    New empirical formula for calculating (n, p) reaction cross-sections at 14.5 MeV neutrons
    (WORLD SCIENTIFIC PUBL CO PTE LTD, 2020) Akrawy, Dashty T.; Ahmed, Ali H.; Tel, Eyüp; Aydın, Abdullah; Sihver, L.
    An empirical formula to calculate the (n, p) reaction cross-sections for 14.5 MeV neutrons for 183 target nuclei in the range 44 <= A <= 212 is presented. Evaluated cross-section data from TENDL nuclear data library were used to test and benchmark the formula. In this new formula, the nonelastic cross-section term is replaced by the atomic number Z, while the asymmetry parameter-dependent exponential term has been retained. The calculated results are presented in comparison with the seven previously published formulae. We show that the new formula is significantly in better agreement with the measured values compared to previously published formulae.
  • Öğe
    A new formulae study for the (n,2p) reaction cross-section systematics at 14-15 MeV
    (PERGAMON-ELSEVIER SCIENCE LTD, 2020) Kavun, Yusuf; Aydin, Abdullah; Tel, Eyyüp
    The cross-section calculation systematics for nuclear reactions have great importance in describing the particleinduced excitation of nuclei. In this study, for 14-15 MeV of incident neutron energy, it has been suggested new empirical formulae to describe the (n, 2p) reactions cross sections. The new empirical formulae have been obtained for 29 <= A <= 159, 29 <= A <= 103 and 133
  • Öğe
    Crystal structure, Hirshfeld surface analysis and DFT studies of (E)-4-methyl-2-{[(2-methyl-3-nitrophenyl)imino]methyl}phenol
    (INT UNION CRYSTALLOGRAPHY, 2020) Cinar, Emine Berrin; Faizi, Md Serajul Haque; Yagci, Nermin Kahveci; Dogan, Onur Erman; Aydin, Alev Sema; Agar, Erbil; Dege, Necmi
    The title compound, C15H14N2O3, was prepared by condensation of 2-hydroxy-5-methyl-benzaldehyde and 2-methyl-3-nitro-phenylamine in ethanol. The configuration of the C=N bond is E. An intramolecular O-H center dot center dot center dot N hydrogen bond is present, forming an S(6) ring motif and inducing the phenol ring and the Schiff base to be nearly coplanar [C- C-N-C torsion angle of 178.53 (13)degrees]. In the crystal, molecules are linked by C-H center dot center dot center dot O interactions, forming chains along the b-axis direction. The Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H center dot center dot center dot H (37.2%), C center dot center dot center dot H (30.7%) and O center dot center dot center dot H (24.9%) interactions. The gas phase density functional theory (DFT) optimized structure at the B3LYP/ 6-311 G(d,p) level is compared to the experimentally determined molecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.
  • Öğe
    Nuclear structure properties of even-even chromium isotopes and the effect of deformation on calculated electron capture cross sections
    (ELSEVIER, 2020) Nabi, Jameel-Un; Boyukata, Mahmut; Ullah, Asim; Riaz, Muhammad
    In this study, we investigate the role of the nuclear deformation on the calculated electron capture cross section (ECC) of even-even chromium (Cr) isotopes. We first determined the nuclear structure properties of these nuclei within the interacting boson model-1 (IBM-1). The energy spectra and E2 transition probabilities were calculated by fitting the parameters in the model formalism. The analysis of the potential energy surface were also performed to predict the geometric shape of the Cr nuclei by plotting their contour plot in the plane of (beta, gamma ) deformation parameters. Later, we calculated the ECC within the proton-neutron quasiparticle random phase approximation (pn-QRPA) model. In particular we studied how the calculated ECC changed with different values of nuclear deformation parameter. The calculated Gamow-Teller (GT) strength distributions were widely spread among the daughter states. The total GT strength decreased with increasing value of the beta parameter. The computed ECC values, however, increased with increase in the beta value of the Cr isotopes. (c) 2020 Elsevier B.V. All rights reserved.