Abstract: This invention relates to an acoustic energy absorbing material which abss sound energy underwater and its performance is independent of the surrounding hydrostatic pressure. It consists of a non-conducting elastomeric matrix having piezoelectric or magnetostrictive particles disposed therein for converting incident soundwave energy into heat, a corrosion resistant coating on the particles for optimizing energy absorption of sonar waves of predetermined frequency, the elastomeric matrix designed so as to have a Poisson's ratio of about 0.5 for effectively utilizing all particles so the incident soundwaves are applied to the particles as a hydrostatic stress distribution, and the acoustic energy absorbing material consisting of a plurality of thin layers of the elastomeric matrix and having high energy absorption per unit volume for providing a slight impedance mismatch between successive layers thus absorbing the predetermined energy of the soundwaves.

Abstract: A method of determining the amount of fatigue or stress-corrosion damage occurring in a member includes the step of matching the target material of the x-ray tube with the material of the member such that x-rays from such target material are capable of penetrating beyond the work hardened surface layer of the member. Since the work hardened surface layer extends up to a depth of from about 100 to 200 micrometers in most metallic materials, the x-ray radiation should at least penetrate to a depth of from about 200 to about 400 micrometers to provide x-ray diffraction line intensity profiles from which the excess dislocation density for the material can be determined. The ratio of the average excess dislocation density of the member to the critical excess dislocation density at failure is equivalent to the fatigue or stress-corrosion damage that has occurred to the member.

Abstract: A method of preventing corrosion of incinerators designed to burn sewage sisting essentially of from about 90 to 98 percent water and from about 2 to 10 percent waste solids by increasing the fusion temperature range of the ash product above the operating temperature of the interior surfaces of the incinerator. The sewage is mixed with additive materials selected from the group SiO.sub.2, CaO, Al.sub.2 O.sub.3, MgO wherein the CaO, Al.sub.2 O.sub.3 and MgO are selected from within the range of 10 to 30 percent of the weight of the waste solids and the SiO.sub.2 is selected from within the range of 25 to 30 percent of the weight of the waste solids.

Abstract: Aluminum objects which are designed to be submersed, submerged, or buried e rendered antifouling by anodizing the surface of the aluminum and impregnating therein, for example, an organometallic compound containing tin. Long term antifouling is achieved due to the low rate of leaching of the organotin compound, while adverse environmental effects are minimized.