55,172 research outputs found
Copper(I)-Phosphinite Complexes in Click Cycloadditions: Three-Component Reactions and Preparation of 5-Iodotriazoles
© 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.The remarkable activity displayed by copper(I)–phosphinite complexes of general formula [CuBr(L)] in two challenging cycloadditions is reported: a) the one-pot azidonation/cycloaddition of boronic acids, NaN3, and terminal alkynes; b) the cycloaddition of azides and iodoalkynes. These air-stable catalysts led to very good results in both cases and the expected triazoles could be isolated in pure form under ‘Click-suitable’ conditions
The Earth Mantle-Core Effect in Matter-Induced Asymmetries for Atmospheric Neutrino Oscillations
Earth medium effects in the three-neutrino oscillations of atmospheric
neutrinos are observable under appropriate conditions. This paper generalizes
the study of the medium effects and the possibility of their observation in the
atmospheric neutrino oscillations from the case of neutrinos traversing only
the Earth mantle, where the density is essentially constant, to the case of
atmospheric neutrinos crossing also the Earth core. In the latter case new
resonance-like effects become apparent. We calculate the CPT-odd asymmetry for
the survival probability of muon neutrinos and the observable muon-charge
asymmetry, taking into account the different atmospheric neutrino fluxes, and
show the dependence of these asymmetries on the sign of
and on the magnitude of the mixing angle . A magnetized detector
with a sufficiently good neutrino momentum resolution is required for the
observation of the muon-charge asymmetry generated by the Earth mantle-core
effect.Comment: 14 pages, 5 figure
Multifractal properties of elementary cellular automata in a discrete wavelet approach of MF-DFA
In 2005, Nagler and Claussen (Phys. Rev. E 71 (2005) 067103) investigated the
time series of the elementary cellular automata (ECA) for possible
(multi)fractal behavior. They eliminated the polynomial background at^b through
the direct fitting of the polynomial coefficients a and b. We here reconsider
their work eliminating the polynomial trend by means of the multifractal-based
detrended fluctuation analysis (MF-DFA) in which the wavelet multiresolution
property is employed to filter out the trend in a more speedy way than the
direct polynomial fitting and also with respect to the wavelet transform
modulus maxima (WTMM) procedure. In the algorithm, the discrete fast wavelet
transform is used to calculate the trend as a local feature that enters the
so-called details signal. We illustrate our result for three representative ECA
rules: 90, 105, and 150. We confirm their multifractal behavior and provide our
results for the scaling parametersComment: 8 pages, 5 figures, 21 reference
Multifractal properties of elementary cellular automata in a discrete wavelet approach of MF-DFA
In 2005, Nagler and Claussen (Phys. Rev. E 71 (2005) 067103) investigated the
time series of the elementary cellular automata (ECA) for possible
(multi)fractal behavior. They eliminated the polynomial background at^b through
the direct fitting of the polynomial coefficients a and b. We here reconsider
their work eliminating the polynomial trend by means of the multifractal-based
detrended fluctuation analysis (MF-DFA) in which the wavelet multiresolution
property is employed to filter out the trend in a more speedy way than the
direct polynomial fitting and also with respect to the wavelet transform
modulus maxima (WTMM) procedure. In the algorithm, the discrete fast wavelet
transform is used to calculate the trend as a local feature that enters the
so-called details signal. We illustrate our result for three representative ECA
rules: 90, 105, and 150. We confirm their multifractal behavior and provide our
results for the scaling parametersComment: 8 pages, 5 figures, 21 reference
Homoclinic Orbits around Spinning Black Holes I: Exact Solution for the Kerr Separatrix
Under the dissipative effects of gravitational radiation, black hole binaries
will transition from an inspiral to a plunge. The separatrix between bound and
plunging orbits features prominently in the transition. For equatorial Kerr
orbits, we show that the separatrix is a homoclinic orbit in one-to-one
correspondence with an energetically-bound, unstable circular orbit. After
providing a definition of homoclinic orbits, we exploit their correspondence
with circular orbits and derive exact solutions for them. This paper focuses on
homoclinic behavior in physical space, while in a companion paper we paint the
complementary phase space portrait. The exact results for the Kerr separatrix
could be useful for analytic or numerical studies of the transition from
inspiral to plunge.Comment: 21 pages, some figure
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