A5085650448- Magnetic confinement fusion research
- Fusion materials and technologies
- Photochemistry and Electron Transfer Studies
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Ionosphere and magnetosphere dynamics
- Plasma Diagnostics and Applications
- Electrochemical Analysis and Applications
- Advanced oxidation water treatment
- Laser-Plasma Interactions and Diagnostics
- Lanthanide and Transition Metal Complexes
- Metal complexes synthesis and properties
- Porphyrin and Phthalocyanine Chemistry
- Free Radicals and Antioxidants
- Nuclear Physics and Applications
- Radical Photochemical Reactions
- Magnetism in coordination complexes
- Spectroscopy and Quantum Chemical Studies
- Luminescence and Fluorescent Materials
- Photochromic and Fluorescence Chemistry
- Organometallic Compounds Synthesis and Characterization
- Nuclear reactor physics and engineering
- Solar and Space Plasma Dynamics
University of Lisbon
2011-2025
Institute of Chemical Kinetics and Combustion
2014-2024
Novosibirsk State University
2013-2024
Moscow State University
2023
Lomonosov Moscow State University
2023
Royal Military Academy
2020
Instituto de Engenharia de Sistemas e Computadores Investigação e Desenvolvimento
2002-2019
Siberian Branch of the Russian Academy of Sciences
2006-2019
Culham Science Centre
2009-2019
Novosibirsk Tuberculosis Research Institute
2017
Disruption mitigation is mandatory for ITER in order to reduce forces, mitigate heat loads during the thermal quench and avoid runaway electrons (REs). A fast disruption valve has been installed at JET study by massive gas injection. Different species amounts have investigated with respect timescales efficiency. We discuss of halo currents as well sideways forces vertical displacement events, increased energy dissipation through radiation, which could arise asymmetric radiation suppression REs.
Disruptions are a critical issue for ITER because of the high thermal and magnetic energies that released on short timescales, which results in extreme forces heat loads. The choice material plasma-facing components (PFCs) can have significant impact loads arise during disruption. With ITER-like wall (ILW) JET made beryllium main chamber tungsten divertor, finding is low fraction radiation. This has dropped significantly with ILW from 50–100% total energy being dissipated disruptions CFC...
Disruptions are a major operational concern for next generation tokamaks, including ITER.They may generate excessive heat loads on plasma facing components, large electromagnetic forces in the machine structures and several MA of multi-MeV runaway electrons.A more complete understanding processes methods to suppress them is necessary ensure safe reliable operation future tokamaks.Runaway electrons were studied at JET-ILW showing that their dependencies (accelerating electric field, avalanche...
Abstract A series of experiments have been executed at JET to assess the efficacy newly installed shattered pellet injection (SPI) system in mitigating effects disruptions. Issues, important for ITER disruption mitigation system, such as thermal load mitigation, avoidance runaway electron (RE) formation, radiation asymmetries during quench electromagnetic control and RE energy dissipation addressed over a large parameter range. The efficiency has examined various SPI strategies. paper...
Extensive analysis of disruptions in JET has helped advance the understanding trends disruption-generated runaway electrons. Tomographic reconstruction soft x-ray emission made possible a detailed observation magnetic flux geometry evolution during disruptions. With aid and hard diagnostics electrons have been detected at very beginning A study electron parameters shown that an approximate upper bound for conversion efficiency pre-disruptive plasma currents into runaways is about 60% over...
The role of the COMPASS tokamak in research generation, confinement and losses runaway electron (RE) population is presented. Recently, two major groups experiments aimed at improved understanding control REs have been pursued. First, effects massive gas injection ( Ar/Ne particles) impurity seeding were studied systematically. observed phenomena include generation post-disruption RE beam current conversion from plasma to RE. Zero loop voltage was implemented order study decay simplified...
Abstract Runaway electrons (REs) created during tokamak disruptions pose a threat to the reliable operation of future larger machines. Experiments using shattered pellet injection (SPI) have been carried out at JET investigate ways prevent their generation or suppress them if avoidance is not sufficient. Avoidance possible SPI contains sufficiently low fraction high-Z material, it fired early in advance disruption prone runaway generation. These results are consistent with previous similar...
This paper investigates the effect of ITER-like wall (ILW) on runaway electron (RE) generation through a comparative study similar slow argon injection JET disruptions, performed with different materials. In carbon case, plateau is observed, while in current quench slower and negligibly small. The aim to shed light reason for these differences by detailed numerical modelling which factors affected RE formation. post-disruption profile calculated one-dimensional model electric field,...
To study the runaway electron (RE) dynamics during plasma discharge and develop scenarios for disruption mitigation, a hard x-ray (HXR) spectrometric system has been developed commissioned at ASDEX Upgrade tokamak (AUG). The diagnostic consists of two high-performance spectrometers based on LaBr3(Ce) scintillation detectors supplied with advanced electronics analysis algorithms. These view AUG chamber quasi-radially equatorial plane. measurements were carried out in RE beam generation...
Abstract The photophysics of a number salicylic acid derivatives (SADs) in aqueous solutions was investigated wide range pH by time‐correlated single photon counting ( λ ex = 350 nm, τ resp 300 ps) and fluorescence up‐conversion 266 fs) techniques. acid–base equilibrium constants the ground (p K ) excited states ${\rm p}K_{\rm a}^* $ ), quantum yields as well lifetimes anionic, neutral, cationic forms SADs were determined. Evidence ultrafast excited‐state intramolecular proton transfer...
Ultrafast pump–probe spectroscopy (λpump = 405 nm) was applied to study the primary photochemical processes for PtCl62− and PtBr62− complexes in aqueous alcohol solutions. For PtCl62−, an intermediate with a lifetime of ca. 200 ps registered identified as Adamson radical pair [PtIIICl52−⋯Cl˙]. The transformations give rise successive formation different Pt(III) species. reactions results chain photoaquation solutions reduction Pt(IV) Pt(II) complex, previously reported (I. L. Zheldakov, M....
ITER as a superconducting fusion machine needs efficient wall conditioning techniques for application in the presence of permanent high toroidal magnetic field (i) reducing in-vessel impurity content, (ii) controlling surface hydrogen isotopic ratio and (iii) mitigating long-term tritium inventory build-up. Encouraging results recently obtained with ion-cyclotron (ICWC) present-day tokamaks stellarators have raised ICWC to status one most promising available routine inter-pulse overnight...
Transient absorption and time resolved luminescence spectroscopy were used to study photophysical processes in the macrocycle-appended 1,8-naphthalimide compound H3L, its Eu(III) Gd(III) complexes Eu·L Gd·L, particular naphthalimide-Eu(III) energy-transfer process. In all cases aggregation of naphthalimide chromophores results a low-energy emission feature 470-500 nm region addition fluorescence; this lower-energy has lifetime longer by an order magnitude than monomer fluorescence. was...
Laser pulse photolysis was used to study the nature and reactions of intermediates in photochemistry flat dithiocarbamate complex Cu(Et2dtc)2 CCl4. A nanosecond laser (355 nm) is shown induce intermediate absorption bands bivalent copper whose coordination sphere contains a radical Et2dtc• chloride ion at axial position ([(Et2dtc)Cu(Et2dtc•)Cla]). At room temperature during some microseconds after pulse, this interacts with initial form presumably dimer [Cu2(Et2dtc)3(Et2dtc•)Cl]. The latter...
Studies of the super-thermal and runaway electron behavior in ohmic lower hybrid current drive FT-2 tokamak plasmas have been carried out using information obtained from measurements hard x-ray spectra non-thermal microwave radiation intensity at frequency 10 GHz range (53 ÷ 78) GHz. A gamma-ray spectrometer based on a scintillation detector with LaBr3(Ce) crystal was used, which provides counting rates up to 107 s−1. Reconstruction energy distribution RE interacting poloidal limiter chamber...
Diazide diamino complexes of Pt(iv) are considered as prospective prodrugs in oxygen-free photodynamic therapy (PDT). Primary photophysical and photochemical processes for cis,trans,cis-[Pt(N3)2(OH)2(NH3)2] trans,trans,trans-[Pt(N3)2(OH)2(NH3)2] were studied by means stationary photolysis, nanosecond laser flash photolysis ultrafast kinetic spectroscopy. The process is multistage. first stage the photosubstitution an azide ligand to a water molecule. This was shown be chain reaction...
The significant role of magnetic perturbations in mitigation and losses runaway electrons (REs) was documented dedicated experimental studies RE at the COMPASS tokamak. REs are produced both low density quiescent discharges disruptions triggered by massive gas injection (MGI). seed beginning discharge on subsequent population proved significant. Modulation MHD instabilities observed several characteristic frequencies, as well field oscillations related to power supplies. Magnetic islands...
This paper presents two scenarios used for generation of a runaway electron (RE) beam in the COMPASS tokamak with focus on decay phase and control beam. The first scenario consists massive gas injection argon into current ramp-up phase, leading to disruption accompanied by plateau generation. In second scenario, smaller amount is order isolate RE from high-temperature plasma. performances radial vertical position feedback were experimentally studied analysed. role energy stability seems be...