Abstract: Interpenetrating polymer network composition, of shaped solid polyester material, e.g. new or reused polyester containing particles, sheeting, fiber or fiber fabric, in a matrix of curable prepolymer resin, e.g. a thermosetting phenol-aldehyde resin of basic pH for providing a flame retardant composition, an interfacial dissolving agent for the polyester material, e.g. an aromatic alcohol and/or a halohydrocarbon, optionally an accelerator for the resin, e.g. a weak acid, and optionally a filler, e.g. in a weight ratio of matrix to polyester material of about 0.25-15:1, wherein the polyester material is distributed, e.g.

Abstract: Production of a lightweight, flame retardant, sound absorption composition in the form of a phenol-aldehyde/polyurethane hybrid polymer foam of open cell structure and interconnected continuous porous architecture, by reacting 100 parts by weight phenolic resin, such as a resole resin of an aldehyde and a phenol, e.g. formaldehyde and phenol, having an aldehyde to phenol mole ratio greater than about 1:1; about 50-300 parts by weight aromatic or aliphatic polyisocyanate; about 0-100 parts by weight aliphatic group containing polyol, e.g. a polyether, polyester, polycaprolactone or polybutadiene polyol; and about 0-100 parts by weight filler; in the presence of a catalyst, e.g. a basic and/or metal salt catalyst in an amount of about 0.01-2 parts by weight, and a blowing agent, especially with all reactants but the polyisocyanate being premixed and then combined with the polyisocyanate for reaction in an open mold, e.g. with the resole resin having a pH of about 4.5-9.

Abstract: A fluid driven jet-edge whistle timing system for control rods of a nuclear reactor for producing real-time detection of the timing of each control rod in its scram operation. An important parameter in reactor safety, particularly for liquid metal fast breeder reactors (LMFBR), is the time deviation between the time the control rod is released and the time the rod actually reaches the down position. The whistle has a nearly pure tone signal with center frequency (above 100 kHz) far above the frequency band in which the energy of the background noise is concentrated. Each control rod can be fitted with a whistle with a different frequency so that there is no ambiguity in differentiating the signal from each control rod.

Abstract: A loaded spring in a pressure relief valve or other spring-loaded device is excited with acoustic vibrations and the resonant frequencies of selected vibration modes are measured. Changes in spring constant due to aging and high temperature are detected by monitoring the longitudinal vibration mode resonant frequency, and changes in loading by monitoring the transverse and/or torsional vibration mode resonant frequency. The pressure set point is ascertained from manufacturing data of resonant frequency versus set point.