Abstract: A system and method of rapidly obtaining quantitative information as to the elemental constituents of coal, particularly the oxygen and sulfer content thereof. The system makes use of the photonuclear interaction to produce the desired radioactivity in the coal constituents. The above mentioned interaction is induced by high energy x-rays from a suitable electron accelerator. The induced radioactivity manifests itself by the emission of characteristic gamma rays among other things. These gamma rays are detected by conventional energy sensitive gamma-ray detectors such as germanium or sodium iodide crystals. The resultant signals are sorted and analyzed to provide the desired information.

Abstract: A system and method of obtaining the maximum amount of information availa in photographs or other objects in which the optical density is far below normal. The system makes use of an unconventional system of illumination combined with conventional projection imaging optics to form a real image of the object using only light scattered by the individual particles which form the object.

Abstract: A method for producing a replica image with enhanced contrast from an orial photographic image comprising toning the original photographic negative with a stable photofissionable isotope material, placing the toned negative in contact with a replication plate made from a transparent material in which damage tracks left by fission fragments may be made visible by some process such as etching, irradiating the toned negative with high-energy X-rays, and etching the replication plate to render the damage tracks visible and thereby produce the replica image.

Abstract: An instrument for measuring the energy fluence of a pulsed X-ray field inendent of the energy of the photons constituting the field. Separate X-radiation absorption assemblies made of particular materials include separate X-radiation detector means therein and are positioned relative to each other to provide output signals proportional to the energy fluence of the incident radiation. This device will operate over an energy fluence rate range from 10.sup.4 ergs/cm.sup.2 to 10.sup.8 ergs/cm.sup.2 delivered in less than one second.