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Information × Registration Number 0212U002428, 0111U008534 , R & D reports Title Devellopment of high-active waste immobilization methods with the use of ceramic materials, carbon-carbon composites and control of intensive irradiation flows during implementation of radiation and nuclear technologies popup.stage_title Head Sayenko Sergey Yuriyovych, Registration Date 23-02-2012 Organization National Science Center "Kharkiv Institute of Physics and Technology popup.description2 - It's carried out research of features low-temperature synthesis synthetic fluorapatite, as for immobilization of radionuclides, which are in ashes from burning wood of the Chernobyl zone (in particular 90Sr), and synthesis fluorapatite with a little raised temperatures for immobilization of radionuclide 90Sr other origin. In the first case, the basic component for synthesis fluorapatite is the ashes received from burning of wood, polluted radionuclides the Chernobyl zone. In the second case, the basic component for synthesis is industrially made pyrophosphate calcium. Results of researches on sintering and hot pressing of a composition fluorapatite with the different maintenance of impurity of strontium - albite in an interval of temperatures 800 - 1000 C, maintenances albite from 1,25 up to 30 weights % are resulted. Features of behaviour of a composition of structure fluorapatite- albite during sintering and hot pressing are certain. The maximal value of density of a composition (fluorapatite Ca9Sr(PO4)6F2+5 weights % albite) 3,0909 g/sm3 that makes 98,5 % from additive density, are received at pressing under pressure 10 МPа and temperature 870 C. - Principle possibility of immobilization of ash of radio-active wastes, which appears at burning of solid and liquid wastes, by its introduction into the pyrocarbon matrix is experimentally confirmed. The density of the achieved material is about 1.6 g/cm3, open porosity 7-9 %, compressive strength – 130 MPa. It is offered and experimentally approved a new technological approach in which in the same process ash is capsulated by the pyrocarbon matrix and external container from carbon/carbon composite material is created. It is shown that in case of external carbon/carbon container destruction ash that was bond by the pyrocarbon matrix is able to keep its integrity during lixiviating in the distilled water at 90 C for a long time. It is shown the principal possibility of decreasing the weight (on ~23 % ) and volume of ash by renewal of oxides in the atmosphere of hydrocarbon gas at 900 C. The offered method of ash binding can be used both as permanent and temporal. In case of a need ash can be renewed and used for the necessary purposes. The critical temperature of propane and butane mixture pyrolysis is set, the principal possibility of thermal gradient gasphase densification of the porous medias methods at the temperatures less than 600 C is shown. - The research to improve the uniformity of the thickness of diamond films and to elucidate the influence of the concentration of methane in the gas mixture on the magnitude of the electrical resistivity has been performed. By optimizing the synthesis parameters and structural elements of the installation sufficiently uniform in thickness and quality the diamond films with the area of 3 cm2 and resistance of 2.7 ... 3.7 1014 Ohm cm, which is more than ten times higher than previous results, has been synthesized. Diamond films for the manufacture of the model of detectors of ionizing radiation are deposited. - We describe the results of investigation developed in NSC KIPT of ionizing-radiation detectors based on polycrystalline diamond film. The advantages of diamond as a material for radiation detectors are the large band gap (5.5 eV), high radiation resistance, almost complete tissue equivalence (Z = 6 against Z = 7.1 for soft tissues), as well as the ability to work at room or higher temperatures. Polycrystalline diamond film synthesis was performed by chemical vapor deposition with the carbon-hydrogen mixture activation with a glow discharge stabilized by a magnetic field. The samples have a surface area not more than 1 cm2 and a thickness of 300 ... 350 microns. Their resistivity (~ 1012 ohm cm) corresponds to the values that the material for detectors of ionizing radiation should fit. Current-voltage characteristics of detectors and their sensitivity to various types of radiation (alpha- particle acceleration of electrons and bremsstrahlung), and radiation resistance were investigated. The first Ukrainian ionizing-radiation detector based on polycrystalline diamond film with high radiation resistance for use in radiation and nuclear technologies based on accelerators, and radiation monitoring systems in the nuclear energy in Ukraine, in particular for in-reactor dosimetry was designed, manufactured and tested. Product Description popup.authors Буколов Олександр Миколайович Верьовкін Андрій Андрійович Грицина Василій Іванович Гуйда Віктор Васильович Гурін Ігор Вячеславович Гурін Вячеслав Анатолійович Дуднік Станіслав Федорович Колосенко Віктор Васильович Кутній Володимир Євдокимович Наконечний Дмитрій Вікторович Опалєв Олег Анатолійович Пилипенко Олександр Васильович Решетняк Олена Миколаївна Рибка Олександр Вікторович Саєнко Сергій Юрійович Соколов Сергій Олександрович Стрельницький Володимир Євгенійович Тарасов Ростислав Васильович Холомєєв Генадій Олександрович Шкуропатенко Володимир Антонович popup.nrat_date 2020-04-02 Close