scholarly journals Design and Operation of First Egyptian IEC Fusion Plasma Device

2019 ◽  
Vol 3 (4) ◽  
pp. 241-248 ◽  
Author(s):  
Gamal M. Elaragi
Keyword(s):  
Voltage Divider ◽  
Neutron Generation ◽  
X Rays ◽  
Fusion Plasma ◽  
Time Resolved ◽  
Plasma Device ◽  
Stainless Steel Cathode ◽  
Confinement Fusion ◽  
Inertial Electrostatic Confinement Fusion

In this paper, Egyptian first inertial electrostatic confinement fusion (IECF) device, constructed at the Egyptian Atomic Energy Authority (EAEA-IEC), is introduced the characterization of IEC Plasma Device. It consists of 2.8 cm stainless steel cathode, 6.5 cm anode diameter with 10 cm diameter 30 cm height vacuum chamber. The discharge current and voltage of plasma discharge has been recorded using current probe and resistive voltage divider respectively. The X-ray emissions in IEC plasma device were investigated by employing time-resolved detector. The temporal distributions of detected x-rays emission are occurring during the initial 1 microsecond. The calculated rate of DD-neutron generation using the same electrode configuration about 106 – 108 neutrons/second.

Particle-in-Cell Simulation of Inertial Electrostatic Confinement Fusion Plasma

2001 ◽  
Vol 39 (3) ◽  
pp. 1211-1216 ◽  
Author(s):  
Masami Ohnishi ◽  
Hodaka Osawa ◽  
Kiyoshi Yoshikawa ◽  
Kai Masuda ◽  
Yasushi Yamamoto
Keyword(s):  
Inertial Electrostatic Confinement ◽  
Fusion Plasma ◽  
Particle In Cell ◽  
Electrostatic Confinement ◽  
Confinement Fusion ◽  
Cell Simulation ◽  
Inertial Electrostatic Confinement Fusion

scholarly journals Small-angle scattering for beginners

2021 ◽  
Vol 54 (6) ◽  
Author(s):  
Cedric J. Gommes ◽  
Sebastian Jaksch ◽  
Henrich Frielinghaus
Keyword(s):  
Small Angle ◽  
Small Angle Scattering ◽  
X Rays ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Time Resolved ◽  
Characterization Methods ◽  
Angle Scattering

Many experimental methods are available for the characterization of nanostructures, but most of them are limited by stringent experimental conditions. When it comes to analysing nanostructures in the bulk or in their natural environment – even as ordinary as water at room temperature – small-angle scattering (SAS) of X-rays or neutrons is often the only option. The rapid worldwide development of synchrotron and neutron facilities over recent decades has opened unprecedented possibilities for using SAS in situ and in a time-resolved way. But, in spite of its huge potential in the field of nanomaterials in general, SAS is covered far less than other characterization methods in non-specialized curricula. Presented here is a rigorous discussion of small-angle scattering, at a technical level comparable to the classical undergraduate coverage of X-ray diffraction by crystals and which contains diffraction as a particular case.

scholarly journals Time-resolved hard X-ray emission from a small plasma focus

1995 ◽  
Vol 13 (1) ◽  
pp. 129-134 ◽  
Author(s):  
S.P. Moo ◽  
C.S. Wong
Keyword(s):  
Experimental Study ◽  
Plasma Focus ◽  
Anode Voltage ◽  
Plastic Scintillator ◽  
Temporal Evolution ◽  
Voltage Divider ◽  
X Rays ◽  
Time Resolved ◽  
X Ray ◽  
Second Period

Some results of an experimental study of the hard X rays emitted from a 15-kV, 3-kJ plasma focus operated in argon are reported. The temporal evolution of the hard X rays detected by a plastic scintillator-photomultiplier detector and the voltage across the focus tube measured by a resistive voltage divider are simultaneously recorded on a two-channel digitizing oscilloscope. Metal absorbers of various thicknesses are used to provide some indications of the energies of the X rays. When the time delay of the detector system with respect to the anode voltage is taken into account, the hard X rays are observed to be emitted about 15 ns before the peak of the anode voltage and last for about 100 ns. There are two periods of emission, the X rays emitted in the first period being more intense, more energetic, and more directional than the X rays emitted in the second period. The X rays are attributed to the bombardment of the anode by energetic electrons generated in the pinch and the disruption phases of the focus.

scholarly journals Characterization of an X-ray Source Generated by a Portable Low-Current X-Pinch

2021 ◽  
Vol 11 (23) ◽  
pp. 11173
Author(s):  
Alexandros Skoulakis ◽  
Evaggelos Kaselouris ◽  
Antonis Kavroulakis ◽  
Christos Karvounis ◽  
Ioannis Fitilis ◽  
...  
Keyword(s):  
Experimental Setup ◽  
X Rays ◽  
Slow Response ◽  
Current Profile ◽  
Current Generator ◽  
Time Resolved ◽  
X Ray ◽  
Upper Limit ◽  
Optical Probing

An X-pinch scheme of a low-current generator (45 kA, 50 ns rise time) is characterized as a potential efficient source of soft X-rays. The X-pinch target consists of wires of 5 μm in diameter—made from either tungsten (W) or gold (Au)-plated W—loaded at two angles of 55° and 98° between the crossed wires. Time-resolved soft X-ray emission measurements are performed to provide a secure correlation with the optical probing results. A reconstruction of the actual photodiode current profile procedure was adopted, capable of overcoming the limits of the slow rising and falling times due to the “slow” response of the diodes and the noise. The pure and Au-plated W deliver an average X-ray yield, which depends only on the angle of the crossed wires, and is measured to be ~50 mJ and ~70 mJ for the 98° and 55° crossed wire angles, respectively. An additional experimental setup was developed to characterize the X-pinch as a source of X-rays with energy higher than ~6 keV, via time-integrated measurements. The X-ray emission spectrum was found to have an upper limit at 13 keV for the Au-plated W configuration at 55°. The portable tabletop X-pinch proved to be ideal for use in X-ray radiography applications, such as the detection of interior defects in biological samples.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Characterization of Rh/Si multilayer structure by HREM and HAADF

1992 ◽  
Vol 50 (1) ◽  
pp. 122-123
Author(s):  
Y. Cheng ◽  
J. Liu ◽  
M.B. Stearns ◽  
D.G. Steams
Keyword(s):  
Normal Incidence ◽  
High Resolution Electron Microscopy ◽  
X Rays ◽  
Beam Direction ◽  
Cross Sectional ◽  
Optical Elements ◽  
Resolution Electron ◽  
Point To Point ◽  
Better Than

The Rh/Si multilayer (ML) thin films are promising optical elements for soft x-rays since they have a calculated normal incidence reflectivity of ∼60% at a x-ray wavelength of ∼13 nm. However, a reflectivity of only 28% has been attained to date for ML fabricated by dc magnetron sputtering. In order to determine the cause of this degraded reflectivity the microstructure of this ML was examined on cross-sectional specimens with two high-resolution electron microscopy (HREM and HAADF) techniques.Cross-sectional specimens were made from an as-prepared ML sample and from the same ML annealed at 298 °C for 1 and 100 hours. The specimens were imaged using a JEM-4000EX TEM operating at 400 kV with a point-to-point resolution of better than 0.17 nm. The specimens were viewed along Si [110] projection of the substrate, with the (001) Si surface plane parallel to the beam direction.

Sign in / Sign up

Export Citation Format

Share Document