92 results about "High atomic number" patented technology

In one example, a method of examining contents of an object is disclosed comprising scanning an object by first and second radiation beams at at least first and second angles, detecting radiation at the first and second angles, and determining whether the object at least potentially comprises high atomic number material, which may be nuclear material or shielding material, based, at least in part, on the detected radiation. In one example, the detected radiation at both angles must be indicative of a region of high atomic number material by the presence of corresponding high density regions, in order for it to be concluded that high atomic number material that may be nuclear material may be present. The determination may be further based on the size of a high density region in one of the images. Systems are also disclosed.

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.

A method for improving resolution of X-ray radiography systems of the type used to obtain images of internal features of human bodies or to view contents of luggage articles, cargo containers and the like comprises positioning a plurality of baffle plates between the rear surface of an X-ray radiation detector array and a back stop used to limit transmitted X-ray radiation to a safe level. The baffle plates are made of a high atomic-number metal such as iron or lead which reduces by absorption, scattering or other attenuating processes the intensity of X-ray radiation back scattered from the back-stop onto the detector array, thus reducing noise contributions to signals output from detector elements of the array and thereby improving the quality of radiographic images formed from detector output signals. A back-scattered X-ray radiation attenuation apparatus according to the present invention utilizes pairs of horizontal upper and lower baffle plates disposed longitudinally rearward from upper and lower sides of individual X-ray radiation detector elements, or groups of elements, of a detector array, and optionally includes pairs of baffle plates disposed transversely to the horizontally disposed plates to thereby form an array of tubular collimatator elements which intercept and attenuate X-ray radiation scattered from locations on a back-stop on lateral sides of as well as above and below the detector elements.

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.

A radiotherapy device comprises a radioactive wire adapted to deliver an intended dosage of radiation to a lesion or other selected body tissues. The radioactive wire comprises an inner core about which is disposed an outer buffer layer of platinum or other suitable metal of high atomic number. The buffer layer preferably comprises a thin, continuous wire wrapped about the inner core. The radiotherapy device may be made into a variety of shapes, such as a straight wire, a helical coil, or other more complex shape, and it may be provided with an elastic memory. The device may be adapted for attachment to a delivery wire for controlled placement, as through a delivery catheter or microcatheter, at the treatment site. When accurate positioning of the device is not necessary, it can simply be injected through the delivery catheter or microcatheter, and in that event a delivery wire is not needed. The device may be provided with mechanically or electrically releasable means for attachment to the delivery wire during delivery, and for releasing the device at the treatment site. The device may be provided with a shoulder, hook, or other suitable gripping means on its distal end, which can be lassoed by a microsnare device for retrieving the device from the body.

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.

An x-ray generator may include a plurality of electron field emitters; a target material; a plurality of energisable solenoid coils; and an electronic power and timing circuit. The generator may provide electrical current to at least one individual solenoid coil to create a magnetic field to cause the path of electrons emitted from the emitter closest to the energised solenoid coil to be defocused and/or deflected before the electrons reach the target material. The target material may comprise a low atomic number material and a high atomic number material, the high atomic number material being arranged in a regular pattern, such that, in use, the electrons may be aimed at either the high or the low atomic number material.

The invention discloses a radiation-proof thermal control coating. A low-atomic-number material is utilized as a surface coating of the thermal control coating, a medium-atomic-number material is utilized as an intermediate coating of the thermal control coating, and a high-atomic-number material is utilized as a bottom coating of the thermal control coating. Compared with a ZnO coating, the coating disclosed by the invention has the advantages that the radiation protection capability is improved by over 10%, the solar absorption ratio alpha s of the coating is about 0.152 and the thermal emissivity epsilon is about 0.886 and is equivalent to that of a ZnO white paint under the same surface density.

Apparatus includes an X-ray source 10, a wavelength dispersive X-ray detector for measuring X-ray fluorescence (XRF) and an energy dispersive X-ray detector 14 again for measuring X-ray fluoresence. Selected elements are measured using the wavelength dispersive process to reduce the overall measurement time compared with using only one of the two detectors or compared to a simple approach of measuring low atomic number elements with the wavelength dispersive detector and high atomic number elements with the energy dispersive detector. The selection can take place dynamically, in particular on the basis of the results of the energy-dispersive detector.

A phantom and film cassette therefor, a composition of high atomic number elements and tissue-equivalent material for a phantom, and an adjustable holder for a phantom. The film cassette comprises sections of tissue-equivalent material, wherein the sections retain a sheet of film when closed together and the phantom composition comprises tissue-equivalent material and high atomic number elements. In operation, dose distributions are determined via computation at various depths within a simulated water-equivalent phantom. After calculating dose distributions, an actual beam is delivered to a phantom containing the cassette, or utilizing a phantom containing high atomic number elements, wherein the phantom mimics human tissue, wherein the phantom houses radiographic film. Images are then generated on the film, the images are converted into an actual dose distribution, and the actual dose distribution is compared with the calculated dose distributions. Finally, a patient is treated based on the beam delivery thus verified.

The invention discloses a preparation and coating method of a total dose radiation shielding coating layer material. The method concretely comprises the following steps: uniformly mixing a high atomic number material with a high-molecular polymer to obtain a mixed coating A; uniformly mixing a low atomic number material with the high-molecular polymer to obtain a mixed coating B; and coating the mixed coating A on the surface layer of a device shell in order to form a high atomic number material layer, and coating the mixed coating B on the surface of the high atomic number material layer to form a low atomic number material layer. The method for preparing the total dose radiation shielding coating layer material and coating the inner wall of the product shell allows the coating layer of the coating layer material to stand up the emission stage of a spacecraft and in-orbit space environment, and the coating layer greatly improves the space total dose radiation environment resistance of the coated product.

The invention provides a medical isotope generation method and device based on a laser wake-field accelerator. Interaction between super-strong and super-short lasers and plasma is utilized to generate a strong flow relativity electron beam. The electron beam is utilized to irradiate a high atomic number target to generate high-flow-strength bremsstrahlung gamma light. The bremsstrahlung gamma light bombards an interested object target to induce a ([gamma], xn+yp) photonuclear reaction or a ([gamma], [gamma]') optical excitation reaction, and object isotopes including gamma rays, electrons, positive electrons and [alpha] particle emitters are generated. By adopting the method provided by the invention, radio isotopes higher in activity are generated, and the cost is relatively low; in addition, the device provided by the invention is compact and convenient to carry, and the device is capable of being placed near a large-sized medical mechanism to be better applied to and serve radiation diagnosis, targeting treatment and other medical applications.