A5066271915- Fusion materials and technologies
- Magnetic confinement fusion research
- Ion-surface interactions and analysis
- Nuclear Materials and Properties
- Superconducting Materials and Applications
- Plasma Diagnostics and Applications
- Advanced materials and composites
- Metal and Thin Film Mechanics
- Particle accelerators and beam dynamics
- Bone Tissue Engineering Materials
- Semiconductor materials and devices
- Integrated Circuits and Semiconductor Failure Analysis
- Diamond and Carbon-based Materials Research
- Nuclear Physics and Applications
- Electron and X-Ray Spectroscopy Techniques
- Advancements in Photolithography Techniques
- Orthopaedic implants and arthroplasty
- Graphite, nuclear technology, radiation studies
- Advanced Materials Characterization Techniques
- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Titanium Alloys Microstructure and Properties
- Advanced Cellulose Research Studies
- X-ray Spectroscopy and Fluorescence Analysis
- Electrospun Nanofibers in Biomedical Applications
Pennsylvania State University
2018-2024
University of Illinois Urbana-Champaign
2014-2023
Oak Ridge National Laboratory
2021
University of Tennessee at Knoxville
2021
Canadian Nuclear Laboratories
2021
Urbana University
2014-2019
Plasma (Russia)
2000-2019
Purdue University West Lafayette
2008-2018
Massachusetts Institute of Technology
2018
Fusion Academy
2018
The accumulation of defects and in particular He bubbles, can have significant implications for the performance materials exposed to plasma magnetic-confinement nuclear fusion reactors. Some most promising candidates deployment into such environments are nanocrystalline as engineering grain boundary density offers possibility tailoring their radiation resistance properties. In order investigate microstructural evolution ultrafine- nanocrystalline-grained tungsten under conditions similar...
National Spherical Torus Experiment [which M. Ono et al., Nucl. Fusion 40, 557 (2000)] high-power divertor plasma experiments have shown, for the first time, that benefits from lithium coatings applied to facing components found previously in limited plasmas can occur also diverted configurations. Lithium were with pellets injected into helium discharges, and an oven directed a collimated stream of vapor toward graphite tiles lower center stack divertor. depositions few milligrams 1g been...
This work discusses the response of ultrafine-grained tungsten materials to high-flux, high-fluence, low energy pure He irradiation. Ultrafine-grained samples were exposed in Pilot-PSI (Westerhout et al 2007 Phys. Scr. T128 18) linear plasma device at Dutch Institute for Fundamental Energy Research (DIFFER) Nieuwegein, Netherlands. The flux on ranged from 1.0 × 1023–2.0 1024 ions m−2 s−1, sample bias a negative (20–65) V, and temperatures 600–1500 °C. SEM analysis clearly shows that have...
Abstract Lithium wall coatings have been shown to reduce recycling, suppress edge-localized modes (ELMs), and improve energy confinement in the National Spherical Torus Experiment (NSTX). Here we document effect of gradually increasing lithium on discharge characteristics, with reference ELMy discharges obtained boronized, i.e. non-lithiated conditions. We observed a continuous but not quite monotonic reduction recycling improvement confinement, gradual alteration edge plasma profiles,...
Nanocrystalline metals are considered highly radiation-resistant materials due to their large grain boundary areas. Here, the existence of a size threshold for enhanced irradiation resistance in high-temperature helium-irradiated nanocrystalline and ultrafine tungsten is demonstrated. Average bubble density, projected area corresponding change volume were measured via transmission electron microscopy plotted as function two ion fluences. grains less than 35 nm possess ∼10–20 times lower this...
Liquid metal plasma-facing components (PFCs) have been proposed as a means of solving several problems facing the creation economically viable fusion power reactors. To date, few demonstrations exist this approach in diverted tokamak and we here provide an overview such work on National Spherical Torus Experiment (NSTX). The Lithium Divertor (LLD) was installed operated for 2010 run campaign using evaporated coatings filling method. LLD consisted copper-backed structure with porous...
We assess key plasma–surface interaction issues of an all-metal plasma facing component (PFC) system for ITER, in particular a tungsten divertor, and beryllium or first wall. Such eliminates problems with carbon divertor erosion T/C codeposition, all-tungsten would better extrapolate to post-ITER devices. The studied are sputtering, transport formation mixed surface layers, tritium contamination, edge-localized mode (ELM) response He-on-W irradiation effects. Code package OMEGA computes PFC...
Metallic mirrors will be used as plasma-viewing elements in all optical and laser diagnostic systems ITER. In the harsh environment of ITER, performance decrease mainly because erosion their surfaces deposition impurities. The deterioration properties directly affect entire respective ITER diagnostics, possibly leading to shutdown. Therefore, R&D on is crucial importance for diagnostics. There a coordinated worldwide programme supervised by Specialists Working Group first International...
Research on the National Spherical Torus Experiment, NSTX, targets physics understanding needed for extrapolation to a steady-state ST Fusion Nuclear Science Facility, pilot plant, or DEMO. The unique operational space is leveraged test theories next-step tokamak operation, including ITER. Present research also examines implications coming device upgrade, NSTX-U. An energy confinement time, τE, scaling unified varied wall conditions exhibits strong improvement of BTτE with decreased electron...
The National Spherical Torus Experiment (NSTX) has undergone a major upgrade, and the NSTX Upgrade (NSTX-U) Project was completed in summer of 2015.NSTX-U first plasma subsequently achieved, diagnostic control systems have been commissioned, H-mode accessed, magnetic error fields identified mitigated, physics research campaign carried out.During ten run weeks operation, NSTX-U surpassed record pulse-durations toroidal (TF), high-performance ~1 MA plasmas comparable to best sustained near...
Lipase mediated biodegradation of carbon dots in the presence H<sub>2</sub>O<sub>2</sub> follows a sequential oxidation pathway.
Lithium wall conditioning has lowered hydrogenic recycling and dramatically improved plasma performance in many magnetic-fusion devices. In this Letter, we report quantum-classical atomistic simulations laboratory experiments that elucidate the roles of lithium oxygen uptake hydrogen amorphous carbon. Surprisingly, show creates a high concentration on carbon surface when bombarded by deuterium. Furthermore, oxygen, rather than lithium, plays key role trapping hydrogen.
Abstract Several proposed mechanisms and theoretical models exist concerning nanostructure evolution on III-V semiconductors (particularly GaSb) via ion beam irradiation. However, making quantitative contact between experiment the one hand model-parameter dependent predictions from different theories other is usually difficult. In this study, we take a approach provide an experimental investigation with range of targets (GaSb, GaAs, GaP) species (Ne, Ar, Kr, Xe) to determine new parametric...