Enhancement of Uranium Oxidation Resistance by Molybdenum Implantation

1983 ◽  
Vol 27 ◽  
Author(s):  
E. N. Kaufmann ◽  
R. G. Musket ◽  
C.A. Colmenares ◽  
B. R. Appleton
Keyword(s):  
Weight Gain ◽  
Oxidation Resistance ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Ion Beam Analysis ◽  
Uranium Metal ◽  
X Ray ◽  
Uranium Oxidation ◽  
Beam Analysis ◽  
The Way

ABSTRACTInitial studies of the oxidation resistance imparted to uranium metal through the implantation of Mo ions have shown that a significantly increased resistance can be achievedfor doses of 5 ×1016/cm2. No enhancement of oxidation resistance was found for doses below 1 ×1016/cm2. We report results of weight-gain measurements, ion-beam analysis, and x-ray diffraction, as well as observations of the way in which the protective implanted layer fails at long exposure times.

scholarly journals Aluminium incorporation in AlxGa1−xN/GaN heterostructures: A comparative study by ion beam analysis and X-ray diffraction

2008 ◽  
Vol 516 (23) ◽  
pp. 8447-8452 ◽  
Author(s):  
A. Redondo-Cubero ◽  
R. Gago ◽  
F. González-Posada ◽  
U. Kreissig ◽  
M.-A. di Forte Poisson ◽  
...  
Keyword(s):  
Comparative Study ◽  
Ion Beam ◽  
X Ray Diffraction ◽  
Ion Beam Analysis ◽  
X Ray ◽  
Beam Analysis

Characterization of Natural and Synthesized FeTiO3 Crystals With RBS/PIXE/XRD

1997 ◽  
Vol 07 (03n04) ◽  
pp. 265-275
Author(s):  
R. Q. Zhang ◽  
S. Yamamoto ◽  
Z. N. Dai ◽  
K. Narumi ◽  
A. Miyashita ◽  
...  
Keyword(s):  
Single Crystals ◽  
Ion Beam ◽  
Pressure Control ◽  
Floating Zone ◽  
X Ray Diffraction ◽  
X Ray ◽  
Beam Analysis ◽  
Ppm Level

Natural FeTiO 3 (illuminate) and synthesized FeTiO 3, single crystals were characterized by Rutherford backscattering spectroscopy combined with channeling technique and particle-induced x-ray emission (RBS-C and PIXE). The results obtained by the ion beam analysis were supplemented by the x-ray diffraction analysis to identify the crystallographic phase. Oriented single crystals of synthesized FeTiO 3 were grown under the pressure control of CO 2 and H 2 mixture gas using a single-crystal floating zone technique. The crystal quality of synthesized FeTiO 3 single crystals could be improved by the thermal treatment but the exact pressure control is needed to avoid the precipitation of Fe 2 O 3 even during the annealing procedure. Natural FeTiO 3 contains several kinds of impurities such as Mn , Mg , Na and Si . The synthesized samples contain Al , Si and Na which are around 100 ppm level as impurities. The PBS-C results of the natural sample imply that Mn impurities occupy the Fe sublattice in FeTiO 3 or in mixed phase between ilmenite and hematite.

THE NEW LOW ENERGY ION BEAM ANALYSIS FACILITY AT MAPUTO UNIVERSITY

1995 ◽  
Vol 05 (04) ◽  
pp. 249-253
Author(s):  
R.J. UTUI ◽  
N.P.O. HOMMAN ◽  
K.G. MALMQVIST
Keyword(s):  
Ion Beam ◽  
Low Energy ◽  
Proton Accelerator ◽  
Nuclear Reaction Analysis ◽  
Beam Diagnostics ◽  
Ion Beam Analysis ◽  
X Ray ◽  
Beam Analysis ◽  
Set Up ◽  
Eduardo Mondlane University

A new Ion Beam Analysis (IBA) facility which was recently installed in the Department of Physics of the Eduardo Mondlane University of Maputo, Mozambique, is described. The set up is based on a low energy (500 keV) Van de Graaff proton accelerator and is intended to be used in particle induced X-ray emission (PIXE), Rutherford Backscattering (RBS) and nuclear reaction analysis (NRA). Preliminary experiments on beam diagnostics were performed successfully and the followed procedure is described.

AIR PARTICULATE RESEARCH CAPABILITY AT THE NEW ZEALAND ION BEAM ANALYSIS FACILITY USING PIXE AND IBA TECHNIQUES

2005 ◽  
Vol 15 (03n04) ◽  
pp. 249-255 ◽  
Author(s):  
W. J. TROMPETTER ◽  
A. MARKWITZ ◽  
P. DAVY
Keyword(s):  
Particulate Matter ◽  
New Zealand ◽  
Limit Of Detection ◽  
Ion Beam ◽  
Anthropogenic Sources ◽  
Ion Beam Analysis ◽  
Air Particulate Matter ◽  
X Ray ◽  
Air Particulate ◽  
Beam Analysis

PIXE and Ion Beam Analysis are one of the few techniques that can be used to identify the elemental composition of air particulates without destroying the filter sample. They are key tools for identifying the sources and determining the relative contribution of biogenic and anthropogenic sources of air particulate matter pollution in our environment. Over the last 8 years, specialised equipment has been designed and built at the New Zealand Ion Beam Analysis facility in Lower Hutt for semi automated analysis of air filters. The equipment and experimental techniques have been refined to improve sensitivities for many of the elements in the periodic table. At GNS, sensitivities have recently been further improved by using two X-ray detectors simultaneously with different amounts of X-ray filtering and collimation. The average limit of detection is improved from 66 ng/cm2 (typical for a setup using a single detector) to 35 ng/cm2 using two detectors simultaneously. The New Zealand Ion Beam Analysis facility now routinely analyses air particulate matter collected on filters from several locations around New Zealand. In this paper, results of air particulate studies from several locations in the Wellington region are presented.

Structure and morphology of copper oxide composite materials synthesized by the arc discharge method

2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840067 ◽  
Author(s):  
F. Fang ◽  
J. Rogers ◽  
P. P. Murmu ◽  
J. Kennedy
Keyword(s):  
Composite Materials ◽  
Copper Oxide ◽  
Arc Discharge ◽  
Ion Beam ◽  
Ion Beam Analysis ◽  
X Ray ◽  
Oxide Composite ◽  
Beam Analysis ◽  
Arc Current ◽  
Discharge Method

Copper oxide is a semiconducting compound with a narrow band gap and is used for photoconductive and photothermal applications. Most of the synthesis methods for the preparation of copper oxide composite materials either are unsuitable for mass fabrication or inevitably introduce unwanted impurities. In this work, we report on the synthesis of copper oxide composite materials by the arc discharge method with a pure copper rod as the anode and graphite as the cathode. Ion beam analysis techniques, particle-induced X-ray emission and Rutherford backscattering spectrometry were used to probe the impurities in the copper oxide composites. Ion beam analysis results revealed copper and oxygen as constituent elements with no impurities. X-ray diffraction results discovered the presence of CuO, Cu2O and Cu phases in the composite materials. The morphology of the as-synthesized copper oxide was studied by scanning electron microscopy. Results clearly demonstrated that spherical particles were obtained with an average diameter of 14 [Formula: see text]m (range 2–85 [Formula: see text]m), 35 [Formula: see text]m (range 20–100 [Formula: see text]m) and 50 [Formula: see text]m (range 30–120 [Formula: see text]m) for the arc current of 60 A, 80 A and 95 A, respectively. It was found that the morphology can be controlled by the arc discharge parameters, e.g. a lower arc discharge current contributed to a smaller particle size. This is because the electric arc current influences the nucleation and the growth of the spherical structures. Due to its simplicity of synthesis, the proposed arc discharge is a promising technique for the fabrication of copper oxide composite materials for optical and electrical applications.

Effects of SiC on Oxidation Behavior of ZrB2-Based Composites with MoSi2 and SiC Additives

2014 ◽  
Vol 602-603 ◽  
pp. 457-462 ◽  
Author(s):  
Shu Qi Guo
Keyword(s):  
Weight Gain ◽  
Oxidation Resistance ◽  
Oxidation Behavior ◽  
Bulk Material ◽  
Sample Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scale Layer ◽  
Exposure Temperature ◽  
Reactive Mixture

In this study, oxidation behavior of ZrB2-MoSi2-SiC composite was investigated in the hot-pressed 5-20 vol% SiC-containing ZrB2-20 vol% MoSi2-based composites which were exposed to dry air between 1100°C and 1500°C up to 10 hours. The effects of SiC additive on the oxidation behavior were assessed. Experimental results showed that the weight gain due to oxidation exposure in air increased with increasing exposure temperature and exposure time. Parabolic oxidation behavior was observed for all the compositions composites. On the other hand, the weight gain decreased with increasing amount of SiC added. The addition of SiC improved the oxidation resistance of the composites, and the improvement was enhanced with increasing amount of SiC added. In addition, X-ray diffraction was used to identify major crystalline phases present in both the as-received and the post-oxidized composites. The oxidized sample surface was characterized by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The microstructure of the post-oxidized composites consisted of two characteristic regions: oxidized reactive region and unreactive bulk material region. Furthermore, the oxidized reactive region divided into an outermost dense silica-rich scale layer and oxidized reactive mixture layer. The improvement of the oxidation resistance due to the addition of SiC is associated with the presence of the thicker dense outermost scale layer which inhibited inward diffusion of oxygen through it.

Superconducting Mbtallic Supkrlattices

1986 ◽  
Vol 77 ◽  
Author(s):  
Charles M. Falco ◽  
Ruggero Vaglio ◽  
Annamaria Cucolo
Keyword(s):  
Thin Films ◽  
Ion Beam ◽  
London Penetration Depth ◽  
X Ray Diffraction ◽  
Josephson Tunneling ◽  
X Ray ◽  
Analysis Techniques ◽  
Beam Analysis ◽  
Superlattice Layer

ABSTRACTSince the coherence length is of order 50 Å to 1 μm, it is possible to alternately layer thin films of a superconductor with another material to affect the physical properties of the resulting superlattice. A brief description of our sputtering technique used to prepare superlat t ices consisting of Nb/Cu and Ta/Mo is given. Optical interferometry, x-ray diffraction and ion beam analysis techniques independently confirm that control of ±0.3% is achieved over the amount of material deposited in each layer. Results of a study of Josephson tunneling to Nb/Cu metallic super lattices are reviewed. These measurements enable a determination of the London penetration depth to be made as a function of superlattice layer thickness.

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