Search results for "CLEAR"
showing 10 items of 27042 documents
α decay of the πh11/2 isomer in Ir164
2014
The α -decay branch of the πh 11 / 2 isomer in 164 Ir has been identified using the GREAT spectrometer. The 164 Ir nuclei were produced using the 92 Mo( 78 Kr ,p 5 n ) 164 Ir reaction and separated in flight using the recoil ion transport unit (RITU) gas-filled separator. The measured α -decay energy of 6880 ± 10 keV allowed the excitation of the πh 11 / 2 state in 160 Re to be deduced as 166 ± 14 keV. The half-life of 164 Ir was measured with improved precision to be 70 ± 10 μ sandan α -decay branching ratio of 4 ± 2% was determined. Improved half-life and branching ratio measurements were also obtained for 165 Ir, but no evidence was found for the ground-state decays of either 164 Ir or 1…
First decay study of the very neutron-rich isotope 93Br
2001
The decay of the mass-separated, very neutron-rich isotope 93 Br has been studied by γ spectroscopy. A level scheme of its daughter 93 Kr has been constructed. Level energies, γ-ray branching ratios, and multipolarities suggest spins and parities which are in accord with a smooth systematics of the N = 57 isotones for Z <~ 4 0 , suggesting the N = 56 subshell closure still to be effective in Kr isotopes. So far, there is no indication of a progressive onset of deformation in neutron-rich Kr isotopes. peerReviewed
First evidence of multiple β-delayed neutron emission for isotopes with a > 100
2017
The β-delayed neutron emission probability, Pn, of very neutron-rich nuclei allows us to achieve a better understanding of the nuclear structure above the neutron separation energy, Sn. The emission of neutrons can become the dominant decay process in neutron-rich astrophysical phenomena such as the rapid neutron capture process (r-process). There are around 600 accessible isotopes for which β-delayed one-neutron emission (β1n) is energetically allowed, but the branching ratio has only been determined for about one third of them. β1n decays have been experimentally measured up to the mass A ∼ 150, plus a single measurement of 210Tl. Concerning two-neutron emitters (β2n), ∼ 300 isotopes are …
Probabilità di fuga di "particelle" nucleari da corpi a simmetria sferica
2008
Acidity and basicity of primaryN-phenylnitramines: catalytic effect of protons on the nitramine rearrangement
2002
Para-substituted N-phenylnitramines were prepared either by oxidation of diazonium salts or by nitration under alkaline or acidic conditions. Isotopic [15N-NO2] labelling indicated that the bands characteristic of the N-nitro group appear in the 1318–1323 and 1585–1607 cm−1 regions. In the nitrogen NMR spectra, the nitramino group gives two resonances at −193 ± 3 (NH) and −32 ± 3 ppm (NO2). The chemical shifts in proton and carbon NMR spectra are predictable, based on increments and the additivity rule. The spectral data indicate the lack of conjugation between the nitramino group and another substituent bound to the ring. It seems to contradict the well-known fact that substituents strongl…
N,N-Dicyclohexylnitramine
2016
Molecules of the title compound, C12H22N2O2, are composed of an nitramine group substituted by two cyclohexane rings. The cyclohexane rings have chair conformations, with the exocyclic C—N bonds in axial orientations. In the crystal, C—H...O hydrogen bonds connect the molecules intoC(6) [-101] zigzag chains.
4-Fluoro-N-methyl-N-nitroaniline
2016
Molecules of the title compound, C7H7FN2O2, are composed of a nitramine group which is twisted with the respect to the aromatic ring, with an N—N—C—C torsion angle of −117.38 (12)°. In the molecule, the N—N bond length [1.3510 (15) Å] indicates some double-bond character, while the angle between the aromatic ring and the nitramine group rules out further delocalization in the molecule. In the crystal, C—H...F hydrogen bonds connect the molecules intoC11(6) chains along theaaxis. C—H...O hydrogen bonds form, which featureR22(12) loops and further connect these chains.
Role of the NF-kB pathway and nitric oxide in mammary gland involution after weaning. Implications in breast cancer
2013
INTRODUCCIÓN La glándula mamaria es un órgano dinámico que alcanza su máximo desarrollo funcional con la lactancia, momento en el cual, a través de la producción de leche, aporta nutrientes y protección inmunológica a las crías de los mamíferos. Cuando la lactancia finaliza con el destete, el exceso de tejido glandular debe desaparecer y la glándula sufre una extensa remodelación hasta alcanzar nuevamente un estado pre-gestacional, preparada para un nuevo ciclo. La involución del tejido mamario es un proceso complejo durante el cual se suceden de forma coordinada una serie de eventos como la muerte de las células epiteliales secretoras, la proliferación de tejido adiposo circundante y la re…
Noble Gases as Magnetic Probes in Fullerene Chemistry
2016
Since the early 1990s of the previous century, the use of magnetic active noble gas atom to indirectly probe the size and symmetry of fullerene cage has been reviewed. Molecular modeling of nuclear shielding (and chemical shift) using gauge-including atomic orbital (GIAO) approach at several levels of theory, including Hartree–Fock (HF), density functional theory (DFT), and coupled cluster (CC), is discussed. The advantage of using GIAO calculation to predict and closely reproduce experimental 3He and 129Xe NMR spectra is shown.
Inference of proto-neutron star properties from gravitational-wave data in core-collapse supernovae
2021
The eventual detection of gravitational waves from core-collapse supernovae (CCSN) will help improve our current understanding of the explosion mechanism of massive stars. The stochastic nature of the late post-bounce gravitational wave signal due to the non-linear dynamics of the matter involved and the large number of degrees of freedom of the phenomenon make the source parameter inference problem very challenging. In this paper we take a step towards that goal and present a parameter estimation approach which is based on the gravitational waves associated with oscillations of proto-neutron stars (PNS). Numerical simulations of CCSN have shown that buoyancy-driven g-modes are responsible …