Персона: Писарев, Александр Александрович
Загружается...
Email Address
Birth Date
Научные группы
Организационные подразделения
Организационная единица
Институт лазерных и плазменных технологий
Стратегическая цель Института ЛаПлаз – стать ведущей научной школой и ядром развития инноваций по лазерным, плазменным, радиационным и ускорительным технологиям, с уникальными образовательными программами, востребованными на российском и мировом рынке образовательных услуг.
Статус
Фамилия
Писарев
Имя
Александр Александрович
Имя
37 results
Результаты поиска
Теперь показываю 1 - 10 из 37
- ПубликацияОткрытый доступCOMPARISON OF EROSION AND DEPOSITION IN JET DURING CARBON AND ITER-LIKE CAMPAIGNS(НИЯУ МИФИ, 2015) Krat, S.; Gasparyan, Yu.; Pisarev, A.; Mayer, M.; de Saint-Aubin, G.; Bykov, I.; Coad, P.; Likonen, J.; van Renterghem, W.; Ruset, C.; Widdowson, A.; JET-EFDA, contributors; Гаспарян, Юрий Микаэлович; Крат, Степан Андреевич; Писарев, Александр АлександровичErosion of plasma facing elements in fusion devices is an important question affecting their lifetimes. Redeposition of eroded materials may lead to accumulation of hydrogen isotopes, which makes it an important problem from the perspective of radiological safety. Redeposition in layers with carbon and beryllium could be a channel for hydrogen isotope accumulation.
- ПубликацияОткрытый доступDETERMINATION OF HYDROGEN BINDING ENERGIES WITH DEFECTS IN METALS FROM THERMAL DESORPTION MEASUREMENTS WITH DIFFERENT HEATING RATES(НИЯУ МИФИ, 2015) Zibrov, M.; Gasparyan, Yu.; Shubina, A.; Pisarev, A.; Писарев, Александр Александрович; Гаспарян, Юрий МикаэловичInvestigation of hydrogen isotope behaviour in plasma-facing and structural components is of great importance for successful development of fusion reactors with magnetic confinement. The hydrogen inventory (especially in the metals with a positive heat of solution) is determined by the presence of defects, which act as trapping sites for hydrogen. Therefore precise determination of defects’ parameters, namely binding energies for hydrogen atoms and their concentration is essential. Thermal desorption spectroscopy (TDS) is a commonly used method for such purposes. The trap parameters are usually determined by fitting of simulated TDS spectra to experimental ones using numerical diffusion-trapping codes, such as TMAP7 [1]. In such approach, the determination of the characteristics of the trapping sites is ambiguous – they act as free parameters in the model and, as a result, one spectrum can be fitted by using several combinations of parameters.
- ПубликацияОткрытый доступINTERACTION OF LITHUM-DEUTERIUM FILMS WITH ATMOSPHERIC GASES(НИЯУ МИФИ, 2015) Popkov,A. S.; Krat, S. A.; Gasparyan, Yu. M.; Pisarev, A. A.; Гаспарян, Юрий Микаэлович; Писарев, Александр Александрович; Крат, Степан АндреевичA choice of plasma-facing materials is one of the key issues in thermonuclear fusion reactor design. Lithium as an element with the low atomic number is a promising material for plasma-facing components (PFC) in fusion installations and a number of experiments at tokamaks already demonstrated many positive effects on plasma operation [1,2]. Lithium can be used for conditioning, PFC on the base of of capillary porous system with liquid lithium are also considered. In any way, one can expect lithium co-deposition with hydrogen isotopes at the surface of PFC and at remote areas. Lithium as a good getter can accumulate high amount of hydrogen isotopes (deuterium, tritium) that can be a problem from the safety reason. Deuterium retention and thermal desorption from lithium films formed in plasma discharge were investigated in this work.
- ПубликацияОткрытый доступИЗОТОПНЫЙ ЭФФЕКТ В НАКОПЛЕНИИ ВОДОРОДА В ОСАЖДЁННЫХ ИЗ ПЛАЗМЫ ВОЛЬФРАМОВЫХ СЛОЯХ(НИЯУ МИФИ, 2024) КРАТ, С. А.; ПРИШВИЦЫН, А. С.; ГАСПАРЯН, Ю. М.; ПИСАРЕВ, А. А.; Писарев, Александр Александрович; Пришвицын, Александр Сергеевич; Крат, Степан Андреевич; Гаспарян, Юрий МикаэловичВажность изучения накопления водорода в соосаждённых из плазмы металлических слоях во многом обусловлена опасностью избыточного накопления радиоактивного изотопа трития в термоядерных установках, где со-осаждение материалов стенки с частицами работчего газа – один из основных каналов накопления водорода в установке. Так как эксперименты с использованием трития крайне затруднены технически, опасны и дороги, подавляющее большинство работ в данной области проводится с использованием дейтерия как симулятора трития. При этом предполагается, что накопление трития будет происходить идентично накоплению дейтерия. В связи со сложностью проведения экспериментов с тритием, возможно провести опыты по сравнению свойств протия и дейтерия и сделать некоторые оценки в части трития на основе полученных данных.
- ПубликацияОткрытый доступHYDROGEN AND HELIUM RETENTION IN TUNGSTEN UNDER ION IRRADIATION(НИЯУ МИФИ, 2017) Gasparyan, Yu.; Zibrov, M.; Efimov, V.; Ryabtsev, S.; Ogorodnikova, O.; Pisarev, A.; Писарев, Александр Александрович; Гаспарян, Юрий Микаэлович; Огородникова, Ольга ВячеславовнаInteraction of helium and hydrogen ions with tungsten is intensively investigated during last decades in relation to construction of fusion reactor. Tungsten has the high melting temperature and the energy threshold for sputtering and, therefore, is considered as plasma facing material (PFM) in fusion devices in the area of largest heat loads and small energies of ions (divertor area). In particular, tungsten will be used in the international experimental reactor ITER, which is now under construction.
- ПубликацияОткрытый доступТЕРМОДЕСОРБЦИЯ ДЕЙТЕРИЯ ИЗ РАДИАЦИОННЫХ ДЕФЕКТОВ В ВОЛЬФРАМЕ(НИЯУ МИФИ, 2015) Рябцев, С. А.; Гаспарян, Ю. М.; Зибров, М. С.; Писарев, А. А.; Писарев, Александр Александрович; Гаспарян, Юрий МикаэловичDetrapping of deuterium ions from point defects created by pre-irradiation in polycrystalline tungsten has been studied by thermal desorption spectroscopy. Different fluences and ion energies were used to investigate various types of defects. The heating rate β was also varied in different experiments in the range of 0.15-4 K/s to determine detrapping energies from the shift of peak positions.
- ПубликацияОткрытый доступВЛИЯНИЕ УЛЬТРАФИОЛЕТОВОГО ИЗЛУЧЕНИЯ НА СОДЕРЖАНИЕ И ДЕСОРБЦИЮ ДЕЙТЕРИЯ ИЗ СООСАЖДЕННЫХ ЛИТИЕВЫХ СЛОЕВ(НИЯУ МИФИ, 2021) Хомяков, А. К.; Крат, С. А.; Пришвицын, А. С.; Фефёлова, Е. А.; Гаспарян, Ю. М.; Писарев, А. А.; Писарев, Александр Александрович; Пришвицын, Александр Сергеевич; Гаспарян, Юрий Микаэлович; Крат, Степан АндреевичThe influence of ultraviolet irradiation of co-deposited lithium layers on the content and desorption of deuterium from them is considered. It was found that exposure to ultraviolet radiation suppresses desorption at high temperatures, facilitates desorption at low temperatures. Effects are considered that can form the basis for the development of methods for determining the places of accumulation of lithium hydride in tokamaks with lithium walls, as well as facilitating the removal of heavy hydrogen isotopes from the walls of installations.
- ПубликацияОткрытый доступDeuterium trapping in co-deposited layers of ITER-relevant materials(НИЯУ МИФИ, 2021) Krat, S. A.; Prishvitsyn, A. S.; Vasina, Ya. A.; Fefelova, E. A.; Gasparyan, Yu. M.; Pisarev, A. A.; Писарев, Александр Александрович; Гаспарян, Юрий Микаэлович; Крат, Степан Андреевич; Пришвицын, Александр СергеевичHydrogen isotope accumulation in fusion devices is a serious problem. Because deuterium-tritium mixture will be a working gas in future fusion devices, including ITER tokamak, tritium accumulation is an issue from the perspective of radiation safety. In total, only 700 grams of tritium are allowed to be present in ITER vessel at any time, with additional 120 in the cryopumps, and 180 grams allocated to measurement error, to the total of 1000 grams.
- ПубликацияОткрытый доступHELIUM THERMAL DESORPTION FROM TUNGSTEN AFTER ION BEAM IRRADIATION AT ELEVATED TEMPERATURES(НИЯУ МИФИ, 2019) Ryabtsev, S. A.; Gasparyan, Yu. M.; Harutyunyan, Z. R.; Efimov, V. S.; Aksenova, A. S.; Pisarev, A. A.; Писарев, Александр Александрович; Ефимов, Виталий Сергеевич; Гаспарян, Юрий Микаэлович; Арутюнян, Зорий РобертовичHelium (He) is a product of deuterium-tritium reaction, so appearance of helium impurities will be unavoidable. In addition to He implantation from fusion plasma, He can be introduced into material by both neutron irradiation and tritium radioactive decay. Presence of He in plasma-facing materials may significantly influence their mechanical properties and surface morphology [1, 2], as well as hydrogen isotope recycling [3, 4]. Tungsten (W) will be used as a plasma-facing material in ITER divertor [5], and it is considered also for application in future fusion devices. Therefore, investigation of He interaction with W is of great interest.
- ПубликацияОткрытый доступHYDROGEN CO-DEPOSITION WITH METALS IN PLASMA DISCHARGE(НИЯУ МИФИ, 2017) Krat, S. A.; Gasparyan, Yu. M.; Vasina, Ya. A.; Pisarev, A. A.; Писарев, Александр Александрович; Крат, Степан Андреевич; Гаспарян, Юрий МикаэловичDeposition of a single element film is always accompanied by co-deposition of a certain amount of other elements. This can be done properly to improve properties of the coating or due to contamination by impurities. In the field of thermonuclear fusion research, where hydrogen isotopes are used as a fuel, co-deposition with sputtered material from the wall is one of major mechanisms of hydrogen isotopes accumulation in the installation. Since D-T fuel will be used in ITER and future fusion reactors, accumulation of radioactive tritium will limit the lifespan of the installations due to safety concerns. For example, tritium accumulation in ITER is limited by 1 kg. This is why carbon materials were not accepted for the use in ITER. Basing on experiments, it was predicted that the safety limit could be reached after 100 of shots with tritium. Recent experiments in JET [1] demonstrated in the case of “ITER-like” wall (first wall – Be, divertor area - tungsten) accumulation of deuterium fuel in the co-deposits was 20 times lower than in the full-carbon wall campaign. This is both due to smaller amount of co-deposits and smaller concentration of deuterium in them.