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Electric quadrupole coupling constant eqQ/ h of the extremely proton-rich Al ( I = 5/2, T = 0.47 s) nucleus implanted into an AlO single crystal has been measured for the first time, using the β-ray detecting nuclear quadrupole resonance method ( β-NQR) in a high magnetic field. As a preliminary result, the quadrupole coupling constant was determined as | eqQ/ h(Al) | = 2.66±0.77 MHz. Using the quadrupole coupling constant of Al in AlO as a reference, the Q moment of the ground state of Al was extracted as | Q(Al)| ~ 160 mb, which is well explained by the shell model calculation in the sd-shell model space with the USD interaction. [ABSTRACT FROM AUTHOR]

The nuclear electric quadrupole moment ( Q moment) of the neutron-rich nucleus 33Al ( I = 5/2 , T1/2 = 41 ms) has been measured by the $ \beta$ -ray detected nuclear quadrupole resonance ( $ \beta$ -NQR) method for the first time. The 33Al nucleus is considered to be on the border of the island of inversion within which a significant intrusion of the pf orbits occurs across the N = 20 shell gap and the intrusion causes an anomalous enhancement of the Q moment. Polarized 33Al nuclei were produced from 36S (77.5MeV/ u beams through the fragmentation process and separated by LISE fragment separator at GANIL. The 33Al nuclei were implanted into a Al2O3 single-crystal plate and the $ \beta$ -NQR spectrum was successfully obtained. [ABSTRACT FROM AUTHOR]

Abstract: The electric quadrupole coupling constant of the 31Al ground state is measured to be using two different β-NMR (Nuclear Magnetic Resonance) techniques. For the first time, a direct comparison is made between the continuous rf technique and the adiabatic fast passage method. The obtained coupling constants of both methods are in excellent agreement with each other and a precise value for the quadrupole moment of 31Al has been deduced: . Comparison of this value with large-scale shell-model calculations in the sd and sdpf valence spaces suggests that the 31Al ground state is dominated by normal sd-shell configurations with a possible small contribution of intruder states. The obtained value for and a compilation of measured quadrupole moments of odd-Z even-N isotopes in comparison with shell-model calculations shows that the proton effective charge provides a much better description of the nuclear properties in the sd-shell than the adopted value . [Copyright &y& Elsevier]

Here we report two cases of pathologically confirmed tumor-like demyelinating lesions. In comparison with common primary demyelinating diseases, our cases demonstrated atypical radiologic features, such as a large monofocal lesion with mild brain edema, and open ring-like or focal enhancement on magnetic resonance images, suggesting brain tumors. The clinical manifestations included focal neurologic signs due to the lesions, monophasic episodes without relapse over a long follow-up period, and efficacy of oral corticosteroid therapy. Histological analysis of brain biopsy specimens showed the inflammatory demyelination and preserved axons without tumor cells. The present cases suggest the importance of considering inflammatory demyelinating disease in the different diagnosis of monofocal tumor-like lesion.