摘要:
A method and system for detecting special nuclear materials are disclosed. Said method and system detect the special nuclear materials by making use of the photofission characteristic and thermal neutron induced fission characteristic thereof. In one preferred embodiment, the high density and/or high atomic number region in the object to be detected is also detected first as a suspicious region.
摘要:
The present invention discloses an article inspection device, comprising: an x-ray machine, a collimation unit, a transmission detector array and a scattering detector array. The scattering detector array comprising a plurality of same scattering detector modules arranged in a matrix of i-rows and j-columns. A transmission cross section of the article transmitted by the x-rays is divided into a plurality of same sub-regions arranged in a matrix of i-rows and j-columns. The plurality of scattering detector modules arranged in i-rows and j-columns correspond to the plurality of sub-regions arranged in i-rows and j-columns one by one for detecting pair production effect annihilation photons and Compton-effect scattering photons from the respective sub-regions. Obtaining atomic numbers of the respective sub-regions based on a ratio of the pair production effect annihilation photon count to the Compton-effect scattering photon count, so as to form a three-dimensional image of the article. In addition, the present invention further discloses an article inspection method.
摘要:
The present invention discloses an article inspection device, comprising: a x-ray machine, a collimation unit, a transmission detector array and at least one scattering detector array. Each of the at least one scattering detector array comprising a plurality of same scattering detector modules arranged in a matrix of i-rows and j-columns. A transmission cross section of the article transmitted by the x-rays is divided into a plurality of same sub-regions arranged in a matrix of i-rows and j-columns. The plurality of scattering detector modules arranged in i-rows and i-columns correspond to the plurality of sub-regions arranged in i-rows and j-columns one by one for detecting pair production effect annihilation photons and Compton-effect scattering photons from the respective sub-regions. Obtaining atomic numbers of the respective sub-regions based on a ratio of the pair production effect annihilation photon count to the Compton-effect scattering photon count, so as to form a three-dimensional image of the article. In addition, the present invention further discloses an article inspection method.
摘要:
A photoneutron-x ray source includes a photoneutron conversion target, which outputs both photoneutrons and x-rays simultaneously. The photoneutron-x ray source includes an x-ray generator for generating an x-ray main beam that is applied to the photoneutron conversion target. The photoneutron conversion target generates photoneutrons upon the application of the x-ray main beam to the photoneutron conversion target. The photoneutron conversion target has a body that defines a passageway extending through the body and that is structured such that a first x-ray beam of the x-ray main beam can pass through the passageway without any reaction with the body, while a second x-ray beam of the x-ray main beam can enter the body and react with the body to emit the photoneutrons.
摘要:
A method and a system for contraband detection in an object using photoneutrons and x-rays includes an x-ray generator that generates an x-ray main beam including a first x-ray beam and a second x-ray beam, the first x-ray beam being directed to pass through the object. A photoneutron conversion target is arranged to receive the second x-ray beam so as to generate photoneutrons, the photoneutrons being directed to enter the object and react with the object to emit characteristic γ-rays. An x-ray detecting arrangement is arranged to receive the first x-ray beam that has passed through the object in order to perform x-ray imaging detection of the detected object. A γ-ray detecting arrangement is arranged to receive the characteristic γ-rays in order to perform neutron detection of the object based on the characteristic γ-rays. The x-ray imaging detection and the neutron detection are simultaneously performed.
摘要:
Disclosed is a method of discriminating materials by employing fast neutron and continuous spectral X-ray and an equipment for the same. The method comprising the steps of: (a) transmitting a fast neutron beam produced by a fast neutron source and a continuous spectral X-ray beam produced by a continuous spectral X-ray source through inspected objects; (b) directly measuring the intensity of the transmitted X-rays and the intensity of the transmitted neutrons by a X-ray detector array and a neutron detector array respectively; and (c) identifying the materials of the inspected object by Z-dependency curves formed by the attenuation differences between the neutron beam and X-ray beam transmitted through different materials of the inspected object. This direct measurement of transmitted dual-ray technique has much more efficient than secondary radiations measurement such as neutron activation analysis, has much more material discrimination sensitivity than dual-energy x-ray technique. The respective measurements of neutrons and x-rays make the usages of high detect efficiency neutron detectors and x-ray detectors possible. The using continuous spectral x-ray produced by Linac adds more advantages such as: high penetration ability, high spatial resolution, and high image quality over monoenergetic dual-ray technique.
摘要:
This invention relates to a system for recuperation and utilization of exhaust heat from a reformer, in which a plurality of arc passageways are formed respectively on the opposite outside walls of the reformer body with a plurality of arc-shaped steel sheet or zinc-plated steel sheet, said arch passageways together with the bottom chamber under the reformer body serve as preheating duct, and at least one air inlet above each passageway is disposed above the top of the reformer. Under the effect of a blower, the air above the reformer top passes through the said preheating duct, and absorbs the heat dispersed from the reformer body. The preheated air makes indirect heat exchange with the flue gas through a heat pipe excharger. The temperature of the air after heat exchange rises from the environmental to about 220.degree. C. and the air is then introduced to the reformer and auxiliary boiler for combustion. The temperature of the flue gas drops from about 300.degree. C. to about 160.degree. C. after heat exchange, and then the flue gas exhausts to the atmosphere through a chimney.
摘要:
A photoneutron conversion target for generating photoneutrons by directing an x-ray beam at the photoneutron conversion target includes an elongated body having a first end and a second end. When the photoneutron conversion target is in use, the x-ray beam enters the body and propagates in a direction from the first end to the second end. The body of the photoneutron conversion target is shaped such that propagation of the x-ray beam is substantially proportionate to an intensity distribution of the x-ray beam, so that the greater an intensity of x-rays of the x-ray beam, the greater the propagation distance of the x-rays within the body of the photoneutron conversion target. The photoneutron conversion target according to the invention can make full use of the x-ray beam so as to increase a yield of photoneutrons.
摘要:
A method and a system for contraband detection in an object using photoneutrons and x-rays includes an x-ray generator that generates an x-ray main beam including a first x-ray beam and a second x-ray beam, the first x-ray beam being directed to pass through the object. A photoneutron conversion target is arranged to receive the second x-ray beam so as to generate photoneutrons, the photoneutrons being directed to enter the object and react with the object to emit characteristic γ-rays. An x-ray detecting arrangement is arranged to receive the first x-ray beam that has passed through the object in order to perform x-ray imaging detection of the detected object. A γ-ray detecting arrangement is arranged to receive the characteristic γ-rays in order to perform neutron detection of the object based on the characteristic γ-rays. The x-ray imaging detection and the neutron detection are simultaneously performed.
摘要:
Disclosed is a method of discriminating materials by employing fast neutron and continuous spectral X-ray and an equipment for the same. The method comprising the steps of: (a) transmitting a fast neutron beam produced by a fast neutron source and a continuous spectral X-ray beam produced by a continuous spectral X-ray source through inspected objects; (b) directly measuring the intensity of the transmitted X-rays and the intensity of the transmitted neutrons by a X-ray detector array and a neutron detector array respectively; and (c) identifying the materials of the inspected object by Z-dependency curves formed by the attenuation differences between the neutron beam and X-ray beam transmitted through different materials of the inspected object. This direct measurement of transmitted dual-ray technique has much more efficient than secondary radiations measurement such as neutron activation analysis, has much more material discrimination sensitivity than dual-energy x-ray technique. The respective measurements of neutrons and x-rays make the usages of high detect efficiency neutron detectors and x-ray detectors possible. The using continuous spectral x-ray produced by Linac adds more advantages such as: high penetration ability, high spatial resolution, and high image quality over monoenergetic dual-ray technique.