Magnetic flux concentration effect of Metglas as a function of its sheet aspect ratio was investigated for Metglas/polyvinylidene fluoride laminates. Taking advantage of this effect, the magnetoelectric voltage coefficient of 21.46 V/cm∙Oe for a laminate with 1 mm wide and 30 mm long Metglas sheet (25 μm thick) is achieved, which is much higher than those reported earlier in similar laminates without making use of the flux concentration effect. The results demonstrate an effective means to significantly enhance the sensitivity of magnetostrictive/piezoelectric composite laminates as weak magnetic field sensors.

The magic-angle spinning ' Si nuclear magnetic resonance (NMR) of annealed rf-sputterdeposited amorphous silicon was measured as a function of annealing temperature up to crystallization. The NMR peak width is observed to narrow significantly with little change in peak position. A comparison with Raman-scattering and neutron-diffraction results indicates that the distribution of NMR chemical shifts is modified by variations of the electronic density of states with bond-angle distribution.

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The bulk mechanical properties of two different types of rootzone sands (round and angular) were measured using a cubical triaxial tester. T wo monosize sands (d 50 = 0:375 mm and 0.675 mm) and their 50:50 binary mixtures (d 50 = 0:500 mm) were studied. T he compression, shear, and failure responses of the above-mentioned six compositions were analyzed, compared, and modeled. T wo elastic parameters (bulk and shear moduli) and two elastoplastic parameters (swelling and consolidation indices) of the six sand compositions were also calculated and compared. T he angular sand was more compressible than round sand during isotropic compression. In addition, the angular sands tended to have lower initial bulk density and high porosity values. Among the three different size fractions, the 0.375 mm mixture was least compressible for both sand shapes. T he failure strength and shear modulus of the angular sand were higher than the round sands. In addition, due to their simplicity, phenomenologica l models were developed to predict the compression and shear behavior of the sands. T he prediction models were validated using subangular and subround sands. Average relative difference values were calculated to determine the effectiveness of the prediction models. T he mean average relative difference values for compression pro® les, i.e., volumetric stress vs. volumetric strain, were from 16% to 39%, except for the initial load-response portion ( < 1% volumetric strain). T he predictive models were effective in reproducing the 145 failure responses: at 17.2 kPa con® ning pressure, the mean of average relative difference was 23%; at 34.5 kPa, the mean difference was 24%.