92 results about "High atomic number" patented technology

This invention is directed towards finding, locating, and confirming threat items and substances. The inspection system is designed to detect objects that are made from, but not limited to, special nuclear materials (“SNM”) and / or high atomic number materials. The system employs advanced image processing techniques to analyze images of an object under inspection (“OUI”), which includes, but is not limited to baggage, parcels, vehicles and cargo, and fluorescence detection.

Cast collimators for use in CT imaging systems are described, as are methods of making them. Such collimators may comprise pre-patient collimators, pre-patient filter / collimator assemblies, and / or post-patient collimators. The filters and / or collimators may be made of any suitable high-density, high atomic number material such as lead, a lead alloy, tantalum, tungsten, tungsten suspended in an epoxy matrix, tungsten suspended in a slurry, or the like. Embodiments of these collimators comprise specially-designed channels and vanes that allow them to be precision cast to the necessary degree of accuracy. These channels and vanes are preferably tapered. These collimators and filter / collimator assemblies help minimize the x-ray dose to the patient by minimizing the scattered radiation creation mechanism and by collimating out much of the scattered radiation that would otherwise be subjected to the patient. These collimators may be cast as either single piece structures, or multiple pieces that can be operatively connected together.

A scintigraphic device includes a case open at an application end, and coated by a shielding shell; a collimator positioned inside the case, made of a material with high atomic number and high density and having a plurality of collimation channels extending mutually parallel according to a predefined direction of measurement; a measuring member positioned inside the case in proximity to the collimator and including a scintillation crystal for converting each ionizing radiation originating from a source in exam into light radiation, and at least one photosensor, for determining the energy and the position of each detected event. The measuring member and the collimator are relatively movable to increase and / or reduce the distance between the converter and the application end and consequently to vary the total length of the collimator. The collimator may include two or more blocks at least one of which is movable relative to the others.

Disclosed herein is the use of differences in x-ray linear absorption coefficients to process ore and remove elements with higher atomic number from elements with lower atomic numbers. Use of this dry method at the mine reduces pollution and transportation costs. One example of said invention is the ejection of inclusions with sulfur, silicates, mercury, arsenic and radioactive elements from coal. This reduces the amount and toxicity of coal ash. It also reduces air emissions and the energy required to clean stack gases from coal combustion. Removal of said ejected elements improves thermal efficiency and reduces the pollution and carbon footprint for electrical production.

The intrinsic background of a gamma ray spectrometer is significantly reduced by surrounding the scintillator with a second scintillator. This second (external) scintillator surrounds the first scintillator and has an opening of approximately the same diameter as the smaller central scintillator in the forward direction. The second scintillator is selected to have a higher atomic number, and thus has a larger probability for a Compton scattering interaction than within the inner region. Scattering events that are essentially simultaneous in coincidence to the first and second scintillators, from an electronics perspective, are precluded electronically from the data stream. Thus, only gamma-rays that are wholly contained in the smaller central scintillator are used for analytic purposes.

It is desirable to achieve a co-incident investigative kV source for a therapeutic MV source—a so-called “beams-eye-view” source. It has been suggested that bremsstrahlung radiation from an electron window be employed; we propose a practical structure for achieving this which can switch easily between a therapeutic beam and a beam-eye-view diagnostic beam capable of offering good image resolution. Such a radiation source comprises an electron gun, a pair of targets locatable in the path of a beam produced by the electron gun, one target of the pair being of a material with a lower atomic number than the other, and an electron absorber insertable into and withdrawable from the path of the beam. In a preferred form, the electron gun is within a vacuum chamber, and the pair of targets are located at a boundary of the vacuum chamber. The lower atomic number target can be Nickel and the higher atomic number target Copper and / or Tungsten. The electron absorber can be Carbon, and can be located within the primary collimator, or within one of a plurality of primary collimators interchangeably locatable in the path of the beam. Such a radiation source can be included within a radiotherapy apparatus, to which the present invention further relates. A flat panel imaging device for this source can be optimised for low energy x-rays rather than high energy; Caesium Iodide-based panels are therefore suitable.