89 results about "Bremsstrahlung" patented technology

A light generating system that comprises a narrow evacuated slot defined between at least two high index contrast waveguide elements. The apparatus can be fabricated using a material such as a SOI wafer having an oxide layer thickness of the order of 1 micron and a top silicon layer thickness of the order of 100-150 nm. Electrode contacts are provided to at least two waveguide elements fabricated in the top silicon layer, each waveguide element having a thickness comparable to the top silicon layer thickness, a width of some hundreds of nm, and having a slot having dimensions in the range of 50-200 nm defined therebetween. The length of the slot is at least as long as the slot width. Charged particles, such as electrons, that are emitted and accelerated across the slot by an applied electrical signal provide a source of photons as a consequence of being accelerated and/or decelerated.

A radiation therapy method that includes directing a beam along a beam path toward a treatment area. Performing a correction process on the beam, the process includes selectively collimating the beam based on a dose that takes into account bremsstrahlung interactions caused by the beam.

A non-intrusive container inspection system, including apparatuses and methods, for non-intrusively scanning and inspecting containers employed to transport items therewithin that utilizes forward-scattered bremsstrahlung, or x-rays, for generating multi-plane images of items present within the containers and for distinguishing between multiple materials present in such items. The system is adapted to direct a pulsed bremsstrahlung, or x-ray, beam having multiple spectra in a substantially single direction at a container being scanned and to produce data that corresponds to portions of the beam that either pass through items within the container without being scattered or that are forward-scattered by items within the container. The system employs a detector array having sections specially configured and oriented to receive and produce data corresponding to the non-scattered and forward-scattered portions of the beam.

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.

A double-spectrum imaging device driven by laser to generate an X-ray source comprises a laser device (1), a vacuum chamber (3),a driving laser inlet (2) and a target assembly. The driving laser inlet (2) is arranged on the vacuum chamber (3) and is matched with the laser device (1), the target assembly is arranged in the vacuum chamber (3) and consists of a plane foil target (601) and a support (602), the plane foil target (601) is positioned in the middle of the vacuum chamber (3), andthe plane with the plane foil target (601) divides the vacuum chamber (3) into target-front space and target-rear space. The double-spectrum imaging device is characterized in that spherical bent crystals capable of being gathered are distributed at the front or the rear of the target to diffract X-rays, to-be-measured samples are distributed on a sample support (701) at the downstream of the spherical bent crystals, and backlight imaging information is received by an imager; and bremsstrahlung spectral lines are led to the front or the rear of the target to directly transmit through the to-be-measured samples on the sample support, and backlight imaging information is received by an imager at a signal receiving end.

The invention relates to a bremsstrahlung reflection triode for generating strong pulse hard X rays. The problems that the gap potentials of two cathodes and anodes of an existing bremsstrahlung reflection triode are inconsistent, and a radiation field cannot be fully utilized are solved. The triode comprises a reflection triode cavity, an anode base, an anode, cathodes, transverse cover plates, aforward cover plate, an insulation plate fixing nut, an insulation plate transition piece and an insulation plate. The part, connected with the insulation plate, of the reflection triode cavity is acylinder, the part, away from the insulation plate, of the reflection triode cavity is transited into a closed cavity, and two parallel flat plates are arranged on the opposite surfaces of the closedcavity; the two cathodes are respectively arranged on the two flat plates of the closed cavity; the anode is positioned between the two cathodes; the anode is arranged on the anode base, the anode base is installed on a water line inner cylinder through the insulation plate transition piece, and the insulation plate transition piece is fixed through the insulation plate fixing nut. The transversecover plates are arranged on the two flat plates of the closed cavity respectively, and the forward cover plate is arranged at the axial tail end of the closed cavity.

The invention discloses blades of a multi-blade collimator for electronic wire conformation and intensity modulated radiation therapy (IMRT), which are mainly characterized in that: the blade of the electronic multi-blade collimator is made of tungsten with thickness of 1.50 to 2cm so as to block most of electrons and generate relatively less bremsstrahlung; the end face of the blade is an upright end face, an inclined end face of which the inclined plane forms an angle of 3.75 to 60 degrees with a ray center shaft, and an arc-shaped end face with curvature radius of 0.75 to 0.85cm, and dosage penumbrae generated by the three end faces are basically the same; and the width of the blade is 0.8 to 1.2cm, so that radiated field edge dosage is relatively accurate and the accurate input of the subfield dosage is facilitated. Compared with the photon multi-blade collimator which is commonly used at present, the electronic multi-blade collimator has the advantages of simple structure, small occupied space, low cost, and more suitability for the electronic wire conformation and intensity modulated radiation therapy (IMRT) to better treat superficial tumors.

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.

The invention belongs to the field of medical radioactive diagnosis nuclides, and relates to a <99>Mo production method and <99>Mo production equipment based on a bremsstrahlung and photonuclear reaction bifunctional target. In the prior art, the introduction of a conversion target can cause the low bremsstrahlung efficiency of a method for producing <99>Mo by using electron beams. A purpose of the present invention is to solve the problem in the prior art. According to the present invention, a high-energy electron beam emitted from an electron accelerator directly bombards an integrated bremsstrahlung and photonuclear reaction <100>Mo target; the production equipment comprises an electron accelerator, a target box, a target plate arranged in the target box, and a cooling system, wherein the target plate is a bremsstrahlung and photonuclear reaction bifunctional target plate, the bremsstrahlung and photonuclear reaction bifunctional target plate is a <100>Mo target, the target box hasan opening for the entering of an electron beam, and the electron beam enters the target box and directly bombards the bremsstrahlung and photonuclear reaction bifunctional target to produce <99>Mo. According to the present invention, by using the <100>Mo integrated bremsstrahlung and photonuclear reaction target, the strong self-attenuation on the bremsstrahlung twice in the traditional conversion target methods of high atomic number tungsten (W) and the like can be well overcome so as to greatly improve the production efficiency of <99>mo.

The invention provides a composite test specimen for all-dimensional direct observation of metal material penetration fusion welding micropores. The composite test specimen comprises an upper metal test specimen body and a lower GG17 test specimen body, the top face of the whole composite test piece, namely the top face of the metal test specimen body is a plane, the bottom face of the metal testspecimen body and the top face of the GG17 test specimen body are smooth binding faces, and an included angle of n degrees is formed between the binding face of the metal test specimen body and the GG17 test specimen body and top face of the composite test specimen, wherein n is larger than 0 degree and smaller than 90 degrees. The composite test specimen can be used for all-dimensional direct observation of shapes of the metal material penetration fusion welding micropores and all-dimensional direct observation of plasma in the micropores, observation dead corners do not exist, more precise micropore shapes are provided for study of micropore behaviors and energy absorption mechanisms in the micropores, and accurate in-pore plasma parameters are also provided for study of inverse bremsstrahlung absorption of the plasma.

The invention discloses a hard X-ray flux detection system of a J-TEXT Tokamak device. The hard X-ray flux detection system comprises a hard X-ray detection module, a detection circuit and an AD data acquisition module; the J-TEXT Tokamak device generates a large number of high-speed escape electrons when disruption is operated; the high-speed escape electrons bombard the material of the first wall of the device so as to directly damage the material; great importance should be attached to the density monitoring of the escape electrons; when the escape electrons damage the first wall, thick target bremsstrahlung occurs between the escape electrons and the material, and hard X-rays are generated, and the energy of the hard X-rays can be up to 0.5 to 10MeV; the more escape electrons strike the wall of the device, the higher the energy of the generated hard X-rays is, and the higher pulse voltage outputted by the detector is; hard X-ray optical signals are converted to pulse voltage signals through the hard X-ray detection module; the peak signals of the pulse signals are detected by the detection circuit; the peak signals are transmitted to a computer terminal through the data acquisition card; the computer terminal stores the peak signals; radiation intensity can be determined; and since the radiation intensity is proportional to the amplitude of the pulse signals, the distribution condition of the escape electrons can be obtained.

A self-shielded sterilization apparatus using an electron beam, comprising: an electron beam irradiator for irradiating an electron beam; a shielding for shielding the electron beam irradiated from the electron beam irradiator and a bremsstrahlung of the electron beam; a tray disposed within the shielding for placing thereon an object to be irradiated; an opening for placing an object into and taking the object out of the shielding; and a shielding door for closing the opening. With the above configurations, the apparatus avoids the shield construction taking a large area and the complicated transporting device, which facilitates a miniaturization of the apparatus.

The invention discloses a method for identifying substance by simulating dual energy X-ray imaging by utilizing a Monte Carlo method, which relates to the method for identifying the substance by utilizing the dual energy X-ray imaging and aims at solving the problem of a low substance identification rate in the current security check process. The method comprises the following steps of: step 1, simulating processes of bombarding a tungsten target by electron beams with energies being 9 MeV and 6 MeV by utilizing the Monte Carlo method, generating bremsstrahlung radiation, and obtaining an X-ray spectrum; step 2, carrying out alignment for the X-ray spectrum obtained in the step 1, scanning a sample to be detected after the alignment, and obtaining a scanning image; and step 3, analyzing the scanning image obtained in the step 2, obtaining an identification curve of the sample to be detected, and realizing the substance identification according to the relationship between the identification curve and substance atoms. The method disclosed by the invention is suitable for the security check.

The invention discloses a laser shock peening method for improving the intensity of a laser induced shock wave by adopting a time sequence double laser pulse, and belongs to the field of laser processing. The laser shock peening method aims at solving the problem that existing laser shock peening systems are generally insufficient in laser energy utilization so as to affect the intensity of shockwaves. The method comprises the step that a laser pulse A and a laser pulse B sequentially irradiate and shock the same position of a workpiece surface in a relative delay mode. The specific process comprises the following steps that firstly, the pulse A irradiates and shocks the surface of the workpiece to form an initial plasma, when the electron density of the initial plasma is reduced to be below the critical density of forming the plasma shielding effect, the pulse B which reaches in delay irradiates and shocks a target area, and a part of the laser energy of the pulse B reaches the surface of an absorption layer so as to continue to gasify and ionize the material of the workpiece; and the other part of the laser energy of the pulse B is subjected to inverse bremsstrahlung absorptionby the initial plasma formed through the pulse A. Under the conditions that the output capability of a laser device is not increased and the irradiation area of a light spot is not changed, the purpose of improving the intensity of the shock wave is achieved.

The invention discloses a method for measuring voltage of a compact superconductive circular accelerator high frequency resonant cavity. Based on Bremsstrahlung principles, the method specifically comprises the following steps: Bremsstrahlung X rays sent out from detecting points in the accelerator high frequency cavity are propagated to an outer part of an accelerator via a collimating aperture, full energy peak energy spectra of the above rays can be detected via a detector, cavity peak value voltage in the accelerator high frequency cavity is in a certain corresponding relation with maximum energy of the rays, and peak value voltage of the high frequency cavity can be measured based on maximum value of the detected energy spectra of the rays. The method disclosed in the invention is simple and reliable in principles, high in feasibility and strong in operability; the peak value voltage of the high frequency cavity can be accurately obtained; compared with a conventional electronics measurement method, cavity distribution parameters can be prevented from being affected by a plurality of factors, the peak value voltage of the high frequency cavity can be accurately reflected, and physical beam tuning requirements for the accelerator can be satisfied.