Shear Ratios Research Articles

Reflecting radial-shear interferometers with an air-spaced system

An earlier paper treated a reflecting radial-shear interferometer made with a thick lens for use with collimated light. This paper treats this interferometer in more detail and includes others designed for an object point at a finite distance and also air-spaced systems suitable for a range of different shear ratios.

The effects of die relief agent on the retention of full coverage castings

The effect of a commercial die relief agent on the retention of castings cemented with a zinc phosphate, a zinc polycarboxylate, or a modified zinc oxide-eugenol cement was studied. Forces required to dislodge unspaced castings from tooth preparations were higher when zinc phosphate cement was the luting medium. Die relief agents resulted in a 32% reduction in the forces required to dislodge castings cemented with zinc phosphate. Data for the other cements did not differ statistically. Shear strength-tensile ratios of the cements indicate that the high shear strength provided by zinc phosphate cement may be negated by the cementation of oversize castings fabricated from relieved dies.

The effect of shear and poisson's ratio in the static bending of wood beams

New displacement equations for the static bending of six common types of simple, finite anisotropic or orthotropic beams are presented. The effect of shear and Poisson's ratios in the determination of Young's modulus by static bending is discussed.