PubMed İndeksli Yayınlar Koleksiyonu

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Browsing PubMed İndeksli Yayınlar Koleksiyonu by Publisher "AIP Publishing"

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    Citation - WoS: 10
    Citation - Scopus: 11
    New 4D and 3D Models of Chaotic Systems Developed From the Dynamic Behavior of Nuclear Reactors
    (AIP Publishing, 2022) Ablay, Guenyaz
    The complex, highly nonlinear dynamic behavior of nuclear reactors can be captured qualitatively by novel four-dimensional (that is, fourth order) and three-dimensional (that is, third order) models of chaotic systems and analyzed with Lyapunov spectra, bifurcation diagrams, and phase diagrams. The chaotic systems exhibit a rich variety of bifurcation phenomena, including the periodic-doubling route to chaos, reverse bifurcations, anti-monotonicity, and merging chaos. The offset boosting method, which relocates the attractor's basin of attraction in any direction, is demonstrated in these chaotic systems. Both constant parameters and periodic functions are seen in offset boosting phenomena, yielding chaotic attractors with controlled mean values and coexisting attractors. Published under an exclusive license by AIP Publishing.
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    Citation - WoS: 53
    Citation - Scopus: 55
    Bond Energies of ThO+ and ThC+: A Guided Ion Beam and Quantum Chemical Investigation of the Reactions of Thorium Cation With O2 and CO
    (AIP Publishing, 2016) Cox, Richard M.; Citir, Murat; Armentrout, P. B.; Battey, Samuel R.; Peterson, Kirk A.
    Kinetic energy dependent reactions of Th+ with O-2 and CO are studied using a guided ion beam tandem mass spectrometer. The formation of ThO+ in the reaction of Th+ with O-2 is observed to be exothermic and barrierless with a reaction efficiency at low energies of k/k(LGS) = 1.21 +/- 0.24 similar to the efficiency observed in ion cyclotron resonance experiments. Formation of ThO+ and ThC+ in the reaction of Th+ with CO is endothermic in both cases. The kinetic energy dependent cross sections for formation of these product ions were evaluated to determine 0 K bond dissociation energies (BDEs) of D-0(Th+-O) = 8.57 +/- 0.14 eV and D-0(Th+-C) = 4.82 +/- 0.29 eV. The present value of D-0(Th+-O) is within experimental uncertainty of previously reported experimental values, whereas this is the first report of D-0(Th+-C). Both BDEs are observed to be larger than those of their transition metal congeners, TiL+, ZrL+, and HfL+ (L = O and C), believed to be a result of lanthanide contraction. Additionally, the reactions were explored by quantum chemical calculations, including a full Feller-Peterson-Dixon composite approach with correlation contributions up to coupled-cluster singles and doubles with iterative triples and quadruples (CCSDTQ) for ThC, ThC+, ThO, and ThO+, as well as more approximate CCSD with perturbative (triples) [CCSD(T)] calculations where a semi-empirical model was used to estimate spin-orbit energy contributions. Finally, the ThO+ BDE is compared to other actinide (An) oxide cation BDEs and a simple model utilizing An(+) promotion energies to the reactive state is used to estimate AnO(+) and AnC(+) BDEs. For AnO(+), this model yields predictions that are typically within experimental uncertainty and performs better than density functional theory calculations presented previously. Published by AIP Publishing.