scholarly journals Photon flux determination of a liquid-metal jet X-ray source by means of photon scattering

2019 ◽  
Vol 34 (7) ◽  
pp. 1497-1502 ◽  
Author(s):  
Malte Wansleben ◽  
Claudia Zech ◽  
Cornelia Streeck ◽  
Jan Weser ◽  
Christoph Genzel ◽  
...  
Keyword(s):  
Electron Beam ◽  
Liquid Metal ◽  
Power Density ◽  
Photon Flux ◽  
Beam Power ◽  
Photon Scattering ◽  
X Ray ◽  
Metal Anode ◽  
Metal Jet

Liquid-metal jet X-ray sources promise to deliver high photon fluxes, which are unprecedented for laboratory based X-ray sources, because the regenerating liquid-metal anode is less sensitive to damage caused by an increased electron beam power density.

scholarly journals Current Status of the Liquid-Metal-Jet X-ray Source Technology

2014 ◽  
Vol 70 (a1) ◽  
pp. C1738-C1738
Author(s):  
Emil Espes ◽  
Björn Hansson ◽  
Christina Gratorp ◽  
Oscar Hemberg ◽  
Göran Johansson ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Current Status ◽  
Beam Power ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fundamental Limitations ◽  
Current State ◽  
Reliable Source ◽  
Order Of Magnitude ◽  
Metal Jet

High-end x-ray diffraction and scattering techniques such as high-resolution XRD, protein crystallography, and SAXS rely heavily on the x-ray source brightness for resolution and exposure time. Traditional solid or rotating anode x-ray tubes are typically limited in brightness by when the e-beam power density melts the anode. The liquid-metal-jet technology has overcome this limitation by using an anode that is already in the molten state. We have previously demonstrated prototype performance of a metal-jet anode x-ray source concept [1-3] with unprecedented brightness in the range of one order of magnitude above current state-of-the art sources. The technology has since been developed into a stable and reliable source for home-lab systems This presentation will review the current status of the technology specifically in terms of stability, lifetime, flux and brightness. It will also discuss details of the liquid-metal-jet technology with a focus on the fundamental limitations of the technology. It will furthermore refer to some recent data from applications within x-ray diffraction and SAXS.

scholarly journals Influence of Beam Power on Young’s Modulus and Friction Coefficient of Ti–Ta Alloys Formed by Electron-Beam Surface Alloying

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1246
Author(s):  
Stefan Valkov ◽  
Dimitar Dechev ◽  
Nikolay Ivanov ◽  
Ruslan Bezdushnyi ◽  
Maria Ormanova ◽  
...  
Keyword(s):  
Electron Beam ◽  
Young’S Modulus ◽  
Coefficient Of Friction ◽  
Young's Modulus ◽  
Beam Power ◽  
Surface Alloying ◽  
Surface Alloys ◽  
X Ray ◽  
The Coefficient Of Friction ◽  
Beam Surface

In this study, we present the results of Young’s modulus and coefficient of friction (COF) of Ti–Ta surface alloys formed by electron-beam surface alloying by a scanning electron beam. Ta films were deposited on the top of Ti substrates, and the specimens were then electron-beam surface alloyed, where the beam power was varied from 750 to 1750 W. The structure of the samples was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Young’s modulus was studied by a nanoindentation test. The coefficient of friction was studied by a micromechanical wear experiment. It was found that at 750 W, the Ta film remained undissolved on the top of the Ti, and no alloyed zone was observed. By an increase in the beam power to 1250 and 1750 W, a distinguished alloyed zone is formed, where it is much thicker in the case of 1750 W. The structure of the obtained surface alloys is in the form of double-phase α’and β. In both surface alloys formed by a beam power of 1250 and 1750 W, respectively, Young’s modulus decreases about two times due to different reasons: in the case of alloying by 1250 W, the observed drop is attributed to the larger amount of the β phase, while at 1750 W is it due to the weaker binding forces between the atoms. The results obtained for the COF show that the formation of the Ti–Ta surface alloy on the top of Ti substrate leads to a decrease in the coefficient of friction, where the effect is more pronounced in the case of the formation of Ti–Ta surface alloys by a beam power of 1250 W.

scholarly journals Determination of X-ray flux using silicon pin diodes

2009 ◽  
Vol 16 (2) ◽  
pp. 143-151 ◽  
Author(s):  
Robin L. Owen ◽  
James M. Holton ◽  
Clemens Schulze-Briese ◽  
Elspeth F. Garman
Keyword(s):  
Light Source ◽  
Energy Deposition ◽  
Photon Flux ◽  
Macromolecular Crystallography ◽  
Pin Diodes ◽  
Web Based ◽  
X Ray ◽  
Swiss Light Source ◽  
Flux Incident

Accurate measurement of photon flux from an X-ray source, a parameter required to calculate the dose absorbed by the sample, is not yet routinely available at macromolecular crystallography beamlines. The development of a model for determining the photon flux incident on pin diodes is described here, and has been tested on the macromolecular crystallography beamlines at both the Swiss Light Source, Villigen, Switzerland, and the Advanced Light Source, Berkeley, USA, at energies between 4 and 18 keV. These experiments have shown that a simple model based on energy deposition in silicon is sufficient for determining the flux incident on high-quality silicon pin diodes. The derivation and validation of this model is presented, and a web-based tool for the use of the macromolecular crystallography and wider synchrotron community is introduced.

Some of these could also be operated in the energy range above lOMeV for experiments designed to determine at which energy level radioactivity can be induced in the irradiated medium. A linac with a maximum energy of 25 MeV was commissioned for the U.S. Army Natick Research and Development Labora­ tories in 1963. Its beam power was 6.5 kW at an electron energy of 10 MeV, 18 kW at 24 MeV. Assuming 100% efficiency, a 1-kW beam can irradiate 360 kg of product with a dose of 10 kGy/h. The efficiency of electron accelerators is higher than that of gamma sources because the electron beam can be directed at the product, whereas the gamma sources emit radiation in all directions. An efficiency of 50% is a realistic assumption for accelerator facilities. With that and 6.5 kW beam power an accelerator of the type built for the Natick laboratories can process about 1.2t/h at 10 kGy. In Odessa in the former Soviet Union, now in the Ukraine, two 20-kW accelerators with an energy of 1.4 MeV installed next to a grain elevator went into operation in 1983. Each accelerator has the capacity to irradiate 200 t of wheat per hour with a dose of 200 Gy for insect disinfestation. This corresponds to a beam utilization of 56% (9). In France, a facility for electron irradiation of frozen deboned chicken meat commenced operation at Berric near Vannes (Brittany) in late 1986. The purpose of irradiation is to improve the hygienic quality of the meat by destroying salmonella and other disease-causing (pathogenic) microorganisms. The electron beam accelerator is a 7 MeV/10 kW Cassitron built by CGR-MeV (10). An irradiation facility of this type is shown in Figure . Because of their relatively low depth of penetration electron beams cannot be used for the irradiation of animal carcasses, large packages, or other thick materials. However, this difficulty can be overcome by converting the electrons to x-rays. As indicated in Figure 9, this can be done by fitting a water-cooled metal plate to the scanner. Whereas in conventional x-ray tubes the conversion of electron energy to x-ray energy occurs only with an efficiency of about %, much higher efficiencies can be achieved in electron accelerators. The conversion efficiency depends on the material of the converter plate (target) and on the electron energy. Copper converts 5-MeV electrons with about 7% efficiency, 10-MeV electrons with 12% efficiency. A tungsten target can convert 5-MeV electrons with about 20%, 10-MeV electrons with 30% efficiency. (Exact values depend on target thickness.) In contrast to the distinct gamma radiation energy emitted from radionuclides and to the monoenergetic electrons produced by accelerators, the energy spectrum of x-rays is continuous from the value equivalent to the energy of the bombarding electrons to zero. The intensity of this spectrum peaks at about one-tenth of the maximum energy value. The exact location of the intensity peak depends on the thickness of the converter plate and on some other factors. As indicated in Figure

1995 ◽  
pp. 40-40
Keyword(s):  
Electron Beam ◽  
Electron Energy ◽  
Maximum Energy ◽  
Metal Plate ◽  
Beam Power ◽  
X Rays ◽  
X Ray ◽  
Emit Radiation ◽  
Electron Accelerators ◽  
Gamma Sources

Electron-Impact Liquid-Metal-Jet Hard x-Ray Sources

2014 ◽  
pp. 91-109
Author(s):  
H.M. Hertz ◽  
O. Hemberg ◽  
M. Otendal ◽  
T. Tuohimaa ◽  
B.A.M. Hansson
Keyword(s):  
Liquid Metal ◽  
Electron Impact ◽  
X Ray ◽  
Metal Jet

Phase-contrast x-ray imaging with a liquid-metal-jet-anode microfocus source

2007 ◽  
Vol 91 (7) ◽  
pp. 074104 ◽  
Author(s):  
T. Tuohimaa ◽  
M. Otendal ◽  
H. M. Hertz
Keyword(s):  
Liquid Metal ◽  
Phase Contrast ◽  
X Ray ◽  
X Ray Imaging ◽  
Metal Jet

A 24 keV liquid-metal-jet x-ray source for biomedical applications

2011 ◽  
Vol 82 (12) ◽  
pp. 123701 ◽  
Author(s):  
D. H. Larsson ◽  
P. A. C. Takman ◽  
U. Lundström ◽  
A. Burvall ◽  
H. M. Hertz
Keyword(s):  
Liquid Metal ◽  
Biomedical Applications ◽  
X Ray ◽  
Metal Jet
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