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
72 results
Результаты поиска
Теперь показываю 1 - 10 из 72
- ПубликацияОткрытый доступInfluence of synthesis conditions on the crystal and local structures of WO3 powders(2019) Zubavichus, Y. V.; Svetogorov, R. D.; Shchetinin, I. V.; Zheleznyi, M. V.; Popov, V. V.; Menushenkov, A. P.; Pisarev, A. A.; Berdnikova, M. M.; Yaroslavtsev, A. A.; Gaynanov, B. R.; Попов, Виктор Владимирович; Менушенков, Алексей Павлович; Писарев, Александр Александрович; Бердникова, Мария Михайловна; Гайнанов, Булат Радикович© Published under licence by IOP Publishing Ltd.Influence of synthesis conditions on the crystal and local structures of WO3 powders prepared by thermal decomposition of ammonium paratungstate and precipitation of tungstates aqueous solutions in strong acid conditions has been investigated. Combination of X-ray powder diffraction, X-ray absorption fine structure spectroscopy, IR- and Raman-spectroscopy, and scanning electron microscopy was used. The calcination of all initial compounds at temperatures ≥ 500C led to formation of the monoclinic γ-WO3 single phase. It was concluded that the neutral octahedral complex [W=0(0H)4(H20)] can be a structural unit of the precursors prepared in acidic suspensions. The local structure of synthesized tungsten oxides consists of edge-shared and corner-shared distorted octahedral WO6 species linked together.
- ПубликацияОткрытый доступOptical radiation from plasma of abnormal glow discharge in various gas mixtures(2019) Muller, T.; Misozhnikov, L.; Stepanova, T. V.; Borisyuk, Y. V.; Mozgrin, D. V.; Nenashev, P. S.; Norakidze, V. S.; Oreshnikova, N. M.; Pisarev, A. A.; Степанова, Татьяна Владимировна; Писарев, Александр Александрович© Published under licence by IOP Publishing Ltd.Optical radiation from plasma of abnormal glow discharge in Ar+N2, He+ N2 and N2+H2 was investigated. Lines of N2 N2 +, N, N+, Ar+, Ar, He, Fe, H, H2 and OH were detected by optical spectrometry. Discharge current and intensities of spectral lines of N2, N2 +, N, and N+ versus the concentration of Ar, He, and H2 in the gas mixtures were measured at various compositions of the working gas.
- ПубликацияОткрытый доступElastic backscattering as a method for the measurement of the integral lithium content in thin films on fusion-relevant substrates(2019) Mayer, M.; Krat, S.; Vasina, Y.; Prishvitsyn, A.; Gasparyan, Y.; Pisarev, A.; Крат, Степан Андреевич; Пришвицын, Александр Сергеевич; Гаспарян, Юрий Микаэлович; Писарев, Александр Александрович© 2019 Elsevier B.V.Different ion beam analysis techniques for the study of thin lithium-containing layers on top of fusion relevant materials are discussed and compared to each other. Elastic backscattering analysis (EBS) with protons is determined to be one of the most promising techniques and allows measurements of Li layers with thicknesses from ∼100 nm up to ∼600 μm, as shown by SIMNRA simulations. The best sensitivity for thin films (∼100 nm) can be achieved using 4 MeV protons with 170° scattering detection angle for layers on Mo and W substrates, and 2 MeV for C substrates. Experimentally EBS measurements were successfully tested for Li films with thicknesses from ∼50 nm up to ∼400 nm after air exposure. The Li films become strongly inhomogeneous and require averaging over multiple measurements in nearby areas. This necessitates averaging over multiple nearby measurement points, and limits the overall precision of the measurement.
- ПубликацияОткрытый доступFormation of nanoscale structures in thin films deposited by reactive magnetron sputtering of binary metal targets in Ar+O2+N2 gas mixture(2019) Bernt, D.; Ponomarenko, V.; Leshchev, S.; Pisarev, A.; Лещев, Сергей Валерьевич; Писарев, Александр Александрович© Published under licence by IOP Publishing Ltd.Bi-metal targets of ZnSn and SiAl were sputtered in A+O2+N2 gas mixtures at various N2/O2 ratios, and the deposited films were investigated by AFM and XPS. No nitrogen was detected in the films even at the highest nitrogen partial pressure in the gas, and the films were oxides. The concentration of the doping metal component in the deposited film increases with the increase of nitrogen partial pressure in the working gas. These experimental observations were supported by numerical calculations of the sputter-deposition process using a SRIM/SIMTRA+RSD software. It was shown that added nitrogen promotes sputtering of doping metal components of the targets, and the concentration of oxygen remains high enough to substitute the less active nitrogen in the growing film. The films consisted of nanograins with the average diameter, which decreased from 18 nm to 3 nm with increase of nitrogen content in the working gas. This effect was explained by the mechanism of abnormal grain growth: the film consisted of grains of oxides of two metals with different concentrations. The doping metal forms very fine nanograins of oxides, which suppress the growth of oxides of the main metal. With increase of nitrogen in the working gas mixture, the sputtering rate of doping metals from the cathodes and their respective concentration in the growing films increases, so the average diameter of oxide grains forming the coating decreases.
- ПубликацияОткрытый доступPost-mortem analyses of gap facing surfaces of tungsten tiles of T-10 ring limiter(2021) Arkhipov, I.; Grashin, S.; Zibrov, M.; Pisarev, A.; Babich, Y.; Berdnikova, M.; Gasparyan, Y.; Gutorov, K.; Efimov, V.; Isaenkova, M.; Krat, S.; Krymskaya, O.; Kurnaev, V.; Stepanova, T.; Vovchenko, E.; Vizgalov, I.; Писарев, Александр Александрович; Бердникова, Мария Михайловна; Гаспарян, Юрий Микаэлович; Гуторов, Константин Михайлович; Ефимов, Виталий Сергеевич; Исаенкова, Маргарита Геннадьевна; Крат, Степан Андреевич; Крымская, Ольга Александровна; Степанова, Татьяна Владимировна; Вовченко, Евгений Дмитриевич© 2020 Elsevier B.V.Surfaces facing the gap between W tiles of the ring limiter of tokamak T-10 were analyzed after T-10 decommissioning using LIBS, SEM/EDA, XRD, TDS, and NRA techniques. Gaps with the width of 5 mm and 0.1 mm were nearly completely covered to their full depths of 22 and 15 mm, respectively, by a deposited film. The film was formed mainly by deposition of lithium that came from Li limiter and transformed in air to Li2CO3 and Li2O. Carbon was deposited from volatile hydrocarbons sputtered from the tokamak walls. Besides, carbon appeared due to chemical reaction with lithium in air. Chemical interactions of W with C, O, and Li led to formation W2C, WC, WO2, and Li2WO4. Carbides formed in W over the entire surface to the full depth of the gaps. Trapping of deuterium and helium in tiles was demonstrated. Possible influence of auto-oscillating discharges on ionization and ion trapping of C,D, and He in gaps is discussed.
- ПубликацияОткрытый доступAnalytical approach for description of deuterium content in deuterium-beryllium co-deposited layers(2021) De, Temmerman, G.; Krat, S.; Gasparyan, Y.; Vasina, Y.; Prishvitcyn, A. S.; Pisarev, A.; Крат, Степан Андреевич; Гаспарян, Юрий Микаэлович; Пришвицын, Александр Сергеевич; Писарев, Александр Александрович© 2021 The Author(s)Available literature data for beryllium content in D-Be co-deposited layers was modeled using newly developed model. It was shown that the model adequately describes the experimental results. An empirical scaling for the available trap concentrations as a function of deuteron energy was introduced in order to improve the agreement between the experimental data and model predictions. The limited recombination rate describes the co-deposition better than the unlimited one. Assuming two types of traps in the film with detrapping energies of 0.8–0.9 and 1.2–1.3 eV and trap concentrations of 10 at. % and 1 at. %, respectively, and the deuterium implantation energy of 15.6 eV, the average relative deviation between experimental and predicted D/Be values of 1.9 was observed, which is better than the empirical D/Be scalings.
- ПубликацияТолько метаданныеEffects of synthesis conditions on the crystal and local structures of high-entropy oxides Ln2M2O7 (Ln = La-Yb, Y; M = Ti, Zr, Ce)(2024) Popov, V. V.; Menushenkov, A. P.; Yastrebtsev, A. A.; Gaynanov, B. R.; Ivanov, A. A.; Rudakov, S. G.; Berdnikova, M. M.; Pisarev, A. А.; Попов, Виктор Владимирович; Менушенков, Алексей Павлович; Ястребцев, Алексей Алексеевич; Гайнанов, Булат Радикович; Иванов, Андрей Анатольевич; Рудаков, Сергей Геннадьевич; Бердникова, Мария Михайловна; Писарев, Александр Александрович
- ПубликацияТолько метаданныеFLOWING LIQUID LITHIUM AS A PLASMA FACING MATERIAL ТЕКУЩИИ ЖИДКИИ ЛИТИИ КАК МАТЕРИАЛ, ОБРАЩЕННЫИ К ПЛАЗМЕ(2024) Pisarev, A. A.; Vertkov, А. V.; Zharkov, M. Yu.; Tarasyuk, G. M.; Писарев, Александр Александрович; Тарасюк, Григорий Михайлович
- 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 доступCHARACTERISATION OF PLASMA PARAMETERS OF INDUCTIVELY - COUPLED PLASMA SOURCE AND ITS APPLICATION FOR NITRIDING OF STEELS(НИЯУ МИФИ, 2015) Meshcheryakova, E.; Zibrov, M.; Kaziev, A.; Khodachenko, G.; Pisarev, A.; Казиев, Андрей Викторович; Писарев, Александр АлександровичInductively coupled plasma (ICP) sources are widely used in many technological applications, including etching of semiconductors, thin film deposition, and surface modification of materials [1]. In particular, ICP plasmas could be attractive for plasma nitriding of metals (steels, titanium, aluminium, etc.) due to the following features: high ionization degree (up to several percent), low pressure (down to 10−4 mbar) that results in increase of energy of ions bombarding a substrate and reduction of their energy spread, and relatively small impurity content in the plasma due to electrodeless nature of the discharge. Consequently, thorough characterization of plasma parameters in ICP sources is essential for revealing the optimal regimes of plasma nitriding.