The Study of the Interaction of the Components of Imitator-Glasses of Glassified Radioactive Wastes With Various Surrounding Rocks

1981 ◽  
Vol 6 ◽  
Author(s):  
V. I. Spitsyn ◽  
A. A. Minaev ◽  
L. I. Barsova ◽  
P. Ya. Glazunov ◽  
V. N. Vetchkanov
Keyword(s):  
Gamma Irradiation ◽  
High Temperatures ◽  
Phosphate Glass ◽  
Phosphate Glasses ◽  
Radioactive Wastes ◽  
X Ray ◽  
Enhanced Diffusion ◽  
Radiation Enhanced Diffusion

ABSTRACTThis work is one of the first attempts to work out a proper technique for the determination of the diffusion of the phosphate glass components into various rocks by using X-ray microanalysis. Under study was thermal and radiationenhanced diffusion of phosphorus, chromium from phosphate glasses into the samples of basalt, metagabbro, metadunite and quartz at high temperatures (to 600°) during gamma irradiation. Radiation enhanced diffusion of ions into rocks.

Bioactive comparison of a borate, phosphate and silicate glass

2006 ◽  
Vol 21 (1) ◽  
pp. 125-131 ◽  
Author(s):  
Wen Liang ◽  
Christian Rüssel ◽  
Delbert E. Day ◽  
Günter Völksch
Keyword(s):  
Silicate Glass ◽  
Phosphate Glass ◽  
Ph Value ◽  
Phosphate Glasses ◽  
Tissue Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Reaction Processes ◽  
Bone Tissue Formation ◽  
Potential Use

A borate glass, phosphate glass, and silicate glass were converted to hydroxyapatite (HA) by soaking the substrates in a solution of K2HPO4 with a pH value of 9.0 at 37 °C. The weight loss of the substrates was studied as a function of time. Unlike the silicate glasses, the reaction processes of the borate glasses and phosphate glasses were bulk dissolution. X-ray diffraction and scanning electron microscopy revealed an initially amorphous product that subsequently crystallized to HA. The data suggest good bioactive characteristics for the borate and phosphate glass and the potential use of them as a favorable template for bone-tissue formation.

Immobilisation of Simulated Plutonium-Contaminated Material in Phosphate Glass: An Initial Scoping Study

2006 ◽  
Vol 932 ◽  
Author(s):  
Paul A. Bingham ◽  
Russell J. Hand ◽  
Charlie R. Scales
Keyword(s):  
Phosphate Glass ◽  
Glass Matrix ◽  
Glass Ceramics ◽  
Additional Benefit ◽  
Phosphate Glasses ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pu Isotopes ◽  
Waste Loading ◽  
Low Levels

ABSTRACTVitrification is a potential route for the immobilisation of Plutonium Contaminated Material (PCM). This is an Intermediate Level Waste (ILW) arising from operations in which there is contact with Pu isotopes. PCM consists of low levels of Pu combined with metals, masonry, glass, ceramics, polymers and other carbonaceous materials. Simulated PCM containing CeO2 as a PuO2 surrogate was mixed with a phosphate precursor and vitrified. Pre-oxidation of PCM simulant prior to vitrification minimised the violence of batch reactions. No pre-oxidation produced inhomogeneous slag-like materials with high residual metals and particulates. Pre-oxidation at 600°C in air and at 1200°C in an O2-rich atmosphere produced more favourable results, with increasingly vitreous products resulting from more oxidised PCM simulant. The most oxidised PCM simulant produced phosphate glasses with low levels of particulate inclusions, as confirmed by x-ray diffraction and scanning electron microscopy. Particulates included iron-rich metallics and aluminous oxides. Increased melting times and temperatures may have reduced the number of inclusions slightly, but O2 bubbling during melting resulted in little additional benefit. Waste loading equivalent to ∼60 weight % of untreated waste may be possible. There was little evidence of Ce partitioning, indicating that it was immobilised within the glass matrix and had little preference for metallic or crystalline phases. These results demonstrate the potential feasibility for vitrification of PCM in phosphate glass, justifying further investigation into this potentially novel solution.

Effect of gamma irradiation on X-ray absorption and photoelectron spectroscopy of Nd-doped phosphate glass

2016 ◽  
Vol 23 (6) ◽  
pp. 1424-1432 ◽  
Author(s):  
V. N. Rai ◽  
Parasmani Rajput ◽  
S. N. Jha ◽  
D. Bhattacharyya ◽  
B. N. Raja Shekhar ◽  
...  
Keyword(s):  
Gamma Irradiation ◽  
Photoelectron Spectroscopy ◽  
Glass Matrix ◽  
Structural Changes ◽  
Phosphate Glasses ◽  
White Line ◽  
Edge Structure ◽  
Xps Spectra ◽  
X Ray ◽  
X Ray Absorption

X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopy (XPS) of Nd-doped phosphate glasses have been studied before and after gamma irradiation. The intensity and the location of the white line peak of theL3-edge XANES of Nd are found to be dependent on the ratio O/Nd in the glass matrix. Gamma irradiation changes the elemental concentration of atoms in the glass matrix, which affects the peak intensity of the white line due to changes in the covalence of the chemical bonds with Nd atoms in the glass (structural changes). Sharpening of the Nd 3d5/2peak profile in XPS spectra indicates a deficiency of oxygen in the glasses after gamma irradiation, which is supported by energy-dispersive X-ray spectroscopy measurements. The ratio of non-bridging oxygen to total oxygen in the glass after gamma radiation has been found to be correlated to the concentration of defects in the glass samples, which are responsible for its radiation resistance as well as for its coloration.

scholarly journals An X-ray Optical Method for the Determination of Diffusion Properties in Very Thin Bimetallic Films

1975 ◽  
Vol 30 (12) ◽  
pp. 1648-1654
Author(s):  
A. Wagendristel
Keyword(s):  
Alloy Formation ◽  
Experimental Check ◽  
X Ray ◽  
Enhanced Diffusion ◽  
Diffusion Parameters ◽  
Diffusion Rates ◽  
Bimetallic Films ◽  
Good Agreement ◽  
Diffusion Properties

Abstract The change of x-ray optical properties during diffusional alloy formation can be used for the evaluation of diffusion parameters in bimetallic thin film couples. The most pronounced phenomenon governed by these properties are the known Kiessig interferences which can be observed in the specular scattered x-ray beam at very small glancing angles. From these interference patterns diffusion data can be obtained by a comparison with calculated reflection curves based on a proper model for diffusion.The most useful thickness range for this method is below 1000 Å, where common x-ray techniques lose their applicability. Since the changes in the interference patterns are most significant in the early diffusion stages, this technique is most suitable for observing initial interdiffusion, which very often occurs with enhanced diffusion rates.The experimental check of the method is performed in the Au-Ag system. Bimetallic films of the pure components were annealed at temperatures between 200 and 300 °C. In this temperature range diffusion parameters from 10-16 to 10-14 cm2/s were found in good agreement with values obtained by other techniques.

Lateral resolution of the electron microbeam analysis

1978 ◽  
Vol 36 (1) ◽  
pp. 542-543
Author(s):  
H.J. Dudek
Keyword(s):  
Quantitative Analysis ◽  
Depth Resolution ◽  
Lateral Resolution ◽  
Cylindrical Particle ◽  
Correction Procedure ◽  
X Ray ◽  
Element Concentrations ◽  
Microbeam Analysis ◽  
The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

Sem and X-Ray Analysis of Renal and Biliary Calculi

1976 ◽  
Vol 34 ◽  
pp. 306-307
Author(s):  
R. J. Narconis ◽  
G. L. Johnson
Keyword(s):  
Chemical Constituents ◽  
Natural State ◽  
X Ray Diffraction ◽  
Chemical Methods ◽  
X Ray ◽  
Additional Dimension ◽  
Biliary Calculi ◽  
Calculus Formation ◽  
Scanning Electron

Analysis of the constituents of renal and biliary calculi may be of help in the management of patients with calculous disease. Several methods of analysis are available for identifying these constituents. Most common are chemical methods, optical crystallography, x-ray diffraction, and infrared spectroscopy. The application of a SEM with x-ray analysis capabilities should be considered as an additional alternative.A scanning electron microscope equipped with an x-ray “mapping” attachment offers an additional dimension in its ability to locate elemental constituents geographically, and thus, provide a clue in determination of possible metabolic etiology in calculus formation. The ability of this method to give an undisturbed view of adjacent layers of elements in their natural state is of advantage in determining the sequence of formation of subsequent layers of chemical constituents.

Preparation And elemental analysis of ancient fibers

1987 ◽  
Vol 45 ◽  
pp. 410-411
Author(s):  
Allen Angel ◽  
Kathryn A. Jakes
Keyword(s):  
Cross Sections ◽  
Physical Structure ◽  
Energy Dispersive ◽  
Archaeological Sites ◽  
X Ray ◽  
Long Term Storage ◽  
Backscattered Electron ◽  
Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

Determination of Stoichiometry of GaAs Component in (Gaas)Ge Epitaxially Grown Thin Films by Electron Microprobe X-Ray Analysis

1990 ◽  
Vol 48 (2) ◽  
pp. 264-265
Author(s):  
D. R. Liu ◽  
S. S. Shinozaki ◽  
R. J. Baird
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Compound Semiconductors ◽  
Energy Dispersive Analysis ◽  
X Ray ◽  
Metastable Alloys ◽  
Lower Voltage

The epitaxially grown (GaAs)Ge thin film has been arousing much interest because it is one of metastable alloys of III-V compound semiconductors with germanium and a possible candidate in optoelectronic applications. It is important to be able to accurately determine the composition of the film, particularly whether or not the GaAs component is in stoichiometry, but x-ray energy dispersive analysis (EDS) cannot meet this need. The thickness of the film is usually about 0.5-1.5 μm. If Kα peaks are used for quantification, the accelerating voltage must be more than 10 kV in order for these peaks to be excited. Under this voltage, the generation depth of x-ray photons approaches 1 μm, as evidenced by a Monte Carlo simulation and actual x-ray intensity measurement as discussed below. If a lower voltage is used to reduce the generation depth, their L peaks have to be used. But these L peaks actually are merged as one big hump simply because the atomic numbers of these three elements are relatively small and close together, and the EDS energy resolution is limited.

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