| 摘要 |
An efficient X-ray radiographic method for recognition of materials of inspected objects and a corresponding device with improved functional possibilities are proposed, ensuring direct determination of the effective atomic number Zeff of the material, its density and thickness, as well as chemical composition. In customs inspection this should ensure practically unambiguous identification of explosives and drugs, and in medical tomography—early diagnostics of cancer tumors, osteoporosis, atherosclerosis and other dangerous and widespread diseases. The method includes X-raying of the inspected objects and recording of the transmitted radiation in several different spectral ranges with different effective energy by multi-element radiation receivers. For this purpose, quasimonochromatic X-ray radiation is used, and detection of radiation transmitted through the inspected object is made by spatially separated multi-element radiation receivers of selective sensitivity, upon each of which quasimonochromatic radiation of specified energy is directed. The background signal values in the absence of the inspected object are pre-recorded for each of said receiver elements under X-ray irradiation of specified energy, and signal values obtained in X-raying of a set of test objects are recorded. All the obtained signals are then normalized with respect to said background signals, and calibration constants are determined, after which the material is recognized by the obtained radiographic reflexes accounting for said calibration constants using special algorithms.
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