The nuclear magnetic moment of the ground state of 57 Cu(I π = 3/2 − , T 1/2 = 196.3 ms) has been measured to be |µ( 57 Cu)| = (2.00 ± 0.05)µN using the β-NMR technique. Together with the known magnetic moment of the mirror partner 57 Ni, the spin expectation value was extracted as Σσz = −0.78 ± 0.13. This is the heaviest isospin T = 1/2 mirror pair above the 40 Ca region for which both ground state magnetic moments have been determined. Discrepancy between present results and shell model calculations in full f p shell giving µ( 57 Cu) ∼ 2.4µN and Σσz ∼ 0.5 implies significant shell breaking at 56 Ni with the neutron number N = 28. The magnetic moment is one of the important fundamental properties of the nucleus and provides key information to understand nuclear structure, especially ideas built on core polarization and the meson exchange effects in the shell model. While the magnetic moments near the stability line in the nuclear chart are well known, we have only limited information on the magnetic moments far from the stability line. Some of the challenges facing ground state nuclear moment measurements include the small spin polarization and low cross sections encountered in the production mechanism for nuclei far removed from the stability line. It is important, however, to go far from the stability line in order to test predictive powers of theoretical models and to find possible variations of nuclear structure from the stability line.In this Letter, we report the first measurement of the magnetic moment of 57 Cu. Since 57 Cu has one proton outside of the 56 Ni core and the magnetic moment of T = 1/2 mirror partner 57 Ni is known, the current result completes the mirror pair and contributes important information for this shell region. The difficulties in the small polarization and low cross section were overcome by using a proton pick up reaction of an intermediate-energy primary beam. The small value for the 57 Cu magnetic moment, discussed later in this paper, implies possible shell breaking at the neutron number N = 28.The magnetic moment can be expressed as the sum of isoscalar Σµ 0 and isovector Σµ z components aswhere l and σ are the orbital and spin angularmomentum operators of the nucleon, respectively, τ is the isospin operator, µ p and µ n are the magnetic moments of free proton and neutron, respectively, and the sum is over all nucleons. The isovector Σµ z part is proportional to the isospin, T z , and changes its sign for T = ±T z . Provided that isospin is a good quantum number, the spin expectation value Σσ z , which is a contribution from nucleon spins to the magnetic moment, can be extracted [1] from the sum of mirror pair magnetic moments aswhere the total spin is I = Σl z + Σσ z /2. In the sd shell, all of the ground state magnetic moments of T = 1/2 mirror nuclei have been measured and there remain several T = 1 and 3/2 isospin multiplets to be measured. There exists, however, virtually no information regarding similar T = 1/2 pairs in the f p shell. A systematic trend of the spin expect...

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A new class of inherently adaptive polymer nanocomposites is developed where stress‐enabled redox reactions are used in the context of a solid polymer electrolyte to form deposits which render mechanical strengthening effects. Experimental investigations were conducted to provide insight into this self‐adaptation phenomenon. Results of tests conducted on bolted composite joints demonstrated the occurrence of this self‐adaptation phenomenon. Experiments were also performed on cracked composite specimens where the potential of the self‐adaptation phenomenon to repair cracks was demonstrated. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40620.

2,18‐Bis(diphenylphosphino)porphyrins undergo peripheral cyclometalation with group 10 transition‐metal salts to afford the corresponding porphyrin‐based PCP pincer complexes. The porphyrinic plane and the PCP‐pincer unit are apparently coplanar, with small strain. The catalytic activities of the porphyrin‐based pincer complexes at the periphery were investigated in the allylation of benzaldehyde with allylstannane and in the 1,4‐reduction of chalcone to discover the electronic interplay between the inner metal and the outer metal in catalysis.

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A β-ray detecting nuclear quadrupole resonance system has been developed at NSCL/MSU to measure ground-state electric quadrupole moments of short-lived nuclei produced as fast rare isotope beams. This system enables quick and sequential application of multiple transition frequencies over a wide range. Fast switching between variable capacitors in resonance circuits ensures sufficient power delivery to the coil in the β-ray detecting nuclear magnetic resonance technique. The fast switching technique enhances detection efficiency of resonance signals and is espe- Preprint submitted to Elsevier 3 February 2018cially useful when the polarization and/or production rate of the nucleus of interest are small and when the nuclear spin is large.

The nuclear states in 23 F have been investigated following the β decay of 23 O. The measurement of 23 O was carried out at the National Superconducting Cyclotron Laboratory using fragments from the reaction of a 48 Ca beam in a Be target. The half-life and total neutron emission probability were determined to be 97(8) ms and 7(2)%, respectively, for 23 O β decay. Ten γ -ray decays in 23 F and a single γ -ray in 22 F were observed to establish the β decay scheme for 23 O. Shell model calculations are in reasonable agreement with the measured β branching and B(GT) values for the lowest energy state. The excitation energies of the first 1/2 + and 3/2 + states have been determined to be 2243(8) and 4066(16) keV, respectively, indicating a widening of the 5/2 + -1/2 + state gap in 23 F. The decay scheme of the largest contaminant 26 Ne in the experiment was established.