Compatibility of advanced tokamak plasma with high density and high radiation loss operation in JT-60U

2005 ◽  
Vol 45 (12) ◽  
pp. 1618-1627 ◽  
Author(s):  
H Takenaga ◽  
N Asakura ◽  
H Kubo ◽  
S Higashijima ◽  
S Konoshima ◽  
...  
2001 ◽  
Vol 41 (2) ◽  
pp. 227-233 ◽  
Author(s):  
H Kubo ◽  
S Sakurai ◽  
N Asakura ◽  
S Konoshima ◽  
H Tamai ◽  
...  
Keyword(s):  

Author(s):  
И.Ю. Сениченков ◽  
Е.Г. Кавеева ◽  
В.А. Рожанский ◽  
Е.А. Сытова ◽  
И.Ю. Веселова ◽  
...  

AbstractModeling of the transition to the detachment of ASDEX Upgrade tokamak plasma with increasing density is performed using the SOLPS-ITER numerical code with a self-consistent account of drifts and currents. Their role in plasma redistribution both in the confinement region and in the scrape-off layer (SOL) is investigated. The mechanism of high field side high-density formation in the SOL in the course of detachment is suggested. In the full detachment regime, when the cold plasma region expands above the X -point and reaches closed magnetic-flux surfaces, plasma perturbation in a confined region may lead to a change in the confinement regime.


2014 ◽  
Vol 1025-1026 ◽  
pp. 410-414
Author(s):  
David Manas ◽  
Martin Ovsik ◽  
Miroslav Manas ◽  
Michal Stanek ◽  
Karel Kocman ◽  
...  

Micromechanical changes in the surface layer of High-density polyethylene HDPE modified by beta radiation were measured by instrumented test of nanohardness. The specimens were prepared by injection technology and subjected to radiation doses of 0, 132, 165, 198 kGy. Measurements of nanohardness showed considerable changes of behavior of surface layer in middle as well as high radiation doses with higher values of indentation hardness and stiffness.


2014 ◽  
Vol 79 ◽  
pp. 01007 ◽  
Author(s):  
L. Casali ◽  
M. Bernert ◽  
R. Dux ◽  
R. Fischer ◽  
A. Kallenbach ◽  
...  

1983 ◽  
Vol 22 (Part 1, No. 12) ◽  
pp. 1910-1914
Author(s):  
Takechiyo Watanabe ◽  
Akihiro Nagao ◽  
Yukio Nakamura ◽  
Satoshi Itoh

2021 ◽  
Author(s):  
Shrish Raj ◽  
Nirmal Bisai ◽  
Vijay Shankar ◽  
Abhijit Sen ◽  
Joydeep Ghosh ◽  
...  

Abstract We present numerical simulation studies on impurity seeding using Nitrogen, Neon, and Argon gases. These impurity gases are ionized by the electron impact ionization. These ions can be at multiply ionized states, recombine again with the plasma electrons, and radiate energy. The radiation losses are estimated using a non-coronal equilibrium model. A set of 2D model equations to describe their self-consistent evolution are derived using interchange plasma turbulence in the edge and SOL regions and solved using BOUT++. It is found that impurity ions (with single or double-positive charges) move in the inward direction with a velocity ∼ 0.02cs so that these fluxes are negative. These fluxes are analyzed for different strengths of an effective gravity that help to understand the impurity ion dynamics. Increased gravity shows an accumulation of certain charged species in the edge region. The radiation loss is seen to have a fluctuation in time with frequency 5-20 kHz that closely follows the behavior of the interchange plasma turbulence. The simulation results on the radiated power and its frequency spectrum compare favourably with observations on the Aditya-U tokamak. The negative fluxes of the impurity ions, their dynamics in the edge region, and the fluctuating nature of the radiation loss are the most important results of this work.


Author(s):  
S. McKernan ◽  
C. B. Carter ◽  
D. Bour ◽  
J. R. Shealy

The growth of ternary III-V semiconductors by organo-metallic vapor phase epitaxy (OMVPE) is widely practiced. It has been generally assumed that the resulting structure is the same as that of the corresponding binary semiconductors, but with the two different cation or anion species randomly distributed on their appropriate sublattice sites. Recently several different ternary semiconductors including AlxGa1-xAs, Gaxln-1-xAs and Gaxln1-xP1-6 have been observed in ordered states. A common feature of these ordered compounds is that they contain a relatively high density of defects. This is evident in electron diffraction patterns from these materials where streaks, which are typically parallel to the growth direction, are associated with the extra reflections arising from the ordering. However, where the (Ga,ln)P epilayer is reasonably well ordered the streaking is extremely faint, and the intensity of the ordered spot at 1/2(111) is much greater than that at 1/2(111). In these cases it is possible to image relatively clearly many of the defects found in the ordered structure.


Sign in / Sign up

Export Citation Format

Share Document