26,311 research outputs found
Research Summary on Fracture of Swollen Rubber
Crack propagation and critical strain in swollen rubbe
On the relaxation modulus of the equivoluminal composition of solithane 113
Relaxation moduli of equivoluminal ring and strip samples of Solithan
Evaluation of meteorological airborne Doppler radar
This paper will discuss the capabilities of airborne Doppler radar for atmospheric sciences research. The evaluation is based on airborne and ground based Doppler radar observations of convective storms. The capability of airborne Doppler radar to measure horizontal and vertical air motions is evaluated. Airborne Doppler radar is shown to be a viable tool for atmospheric sciences research
The Fracture Energy and Some Mechanical Properties of a Polyurethane Elastomer
The energy required to form a unit of new surface in the fracture of a polyurethane elastomer is determined. The rate sensitivity of the material has been reduced by swelling it in toluene. This paper primarily describes the experimental work of measuring the lower limit of the fracture energy. With this value and the creep compliance as a basis, the rate dependence of fracture energy for the unswollen material has been determined. It is thus shown that the dependence of the fracture energy on the rate of crack propagation can be explained by energy dissipation around the tip of the crack. Good agreement between the theoretically and experimentally determined relationships for the rate-sensitive fracture energy is demonstrated
Crossover from a square to a hexagonal pattern in Faraday surface waves
We report on surface wave pattern formation in a Faraday experiment operated
at a very shallow filling level, where modes with a subharmonic and harmonic
time dependence interact. Associated with this distinct temporal behavior are
different pattern selection mechanisms, favoring squares or hexagons,
respectively. In a series of bifurcations running through a pair of
superlattices the surface wave pattern transforms between the two incompatible
symmetries. The close analogy to 2D and 3D crystallography is pointed out.Comment: 4 pages, 4 figure
Charge radius and dipole response of Li
We investigate the consistency of the measured charge radius and dipole
response of Li within a three-body model. We show how these observables
are related to the mean square distance between the Li core and the center
of mass of the two valence neutrons. In this representation we find by
considering the effect of smaller corrections that the discrepancy between the
results of the two measurements is of the order of 1.5. We also
investigate the sensitivity to the three-body structure of Li and find
that the charge radius measurement favors a model with a 50% s-wave component
in the ground state of the two-neutron halo, whereas the dipole response is
consistent with a smaller s-wave component of about 25% value.Comment: 6 pages, 3 figure
Phase relaxation of Faraday surface waves
Surface waves on a liquid air interface excited by a vertical vibration of a
fluid layer (Faraday waves) are employed to investigate the phase relaxation of
ideally ordered patterns. By means of a combined frequency-amplitude modulation
of the excitation signal a periodic expansion and dilatation of a square wave
pattern is generated, the dynamics of which is well described by a Debye
relaxator. By comparison with the results of a linear theory it is shown that
this practice allows a precise measurement of the phase diffusion constant.Comment: 5 figure
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