A non-destructive and on-site digital autoradiography-based tool to identify contaminating radionuclide in nuclear wastes and facilities to be dismantled

Abstract The radiological characterisation of nuclear wastes of a research centre is difficult seen the many different processes that generate waste. Since these wastes may contain radionuclides relevant for the disposal option, the nuclide content and activity have to be known. Considering the fact that some wastes are generated only in minor quantities, complex approaches, involving sampling and successive analysis are generally not justified. Basic physical models can generally be applied to estimate activity ratios from which the radionuclide inventory can be determined by non-destructive assay on waste packages. This article discusses waste streams at the Belgian Nuclear Research Centre SCK•CEN and explains how nuclide inventories and activity are determined. The physical models, used to derive activity ratios and other simple approaches are discussed.

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The Leaching Of The Reactive Powder Concretes: Results On Transfer Properties

MRS Proceedings ◽

10.1557/proc-503-145 ◽

1997 ◽

Vol 503 ◽

Cited By ~ 1

Author(s):

V. Matite ◽

M. Moranville

Keyword(s):

Diffusion Coefficient ◽

Pure Water ◽

Diffusion Cell ◽

Leaching Test ◽

Nuclear Wastes ◽

Reactive Powder ◽

Non Destructive ◽

Transfer Properties ◽

And Diffusion ◽

Non Destructive Techniques

ABSTRACTThe properties of concrete can be altered in aggressive media such as pure water. A leaching test was performed for Reactive Powder Concretes (RPC) in order to evaluate their durability when used as storage of nuclear wastes. Emphasis is placed on the changes of their microstructure, on the tritium diffusion coefficient and on the porosity after leaching. Using mainly non destructive techniques such as SEM, BET and diffusion cell, we found that the leaching affects the RPC microstructure, particularly the anhydrous cement grains. The tritium diffusion coefficient, even lower than that of granite, is however ten times higher after a three month-leaching.

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Luminescence from individual dislocations in II-VI and III-V semiconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088488 ◽

1991 ◽

Vol 49 ◽

pp. 834-835

Author(s):

J W Steeds

Keyword(s):

Group Iv ◽

Luminescence Properties ◽

Carrier Recombination ◽

Transmission Electron ◽

Wide Range ◽

Basic Physics ◽

Semiconducting Compounds ◽

Diamond Group ◽

Non Destructive ◽

Technological Significance

There is a wide range of experimental results related to dislocations in diamond, group IV, II-VI, III-V semiconducting compounds, but few of these come from isolated, well-characterized individual dislocations. We are here concerned with only those results obtained in a transmission electron microscope so that the dislocations responsible were individually imaged. The luminescence properties of the dislocations were studied by cathodoluminescence performed at low temperatures (~30K) achieved by liquid helium cooling. Both spectra and monochromatic cathodoluminescence images have been obtained, in some cases as a function of temperature.There are two aspects of this work. One is mainly of technological significance. By understanding the luminescence properties of dislocations in epitaxial structures, future non-destructive evaluation will be enhanced. The second aim is to arrive at a good detailed understanding of the basic physics associated with carrier recombination near dislocations as revealed by local luminescence properties.

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Forensic Identifications Aided by Scanning Electron Microscopy of Silicone-Epoxy Microreplicas of Calcified and Cornified Structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117017 ◽

1975 ◽

Vol 33 ◽

pp. 678-679 ◽

Cited By ~ 3

Author(s):

R.F. Sognnaes

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Forensic Science ◽

George Washington ◽

Epithelial Surface ◽

Extended Application ◽

Tissue Surfaces ◽

Non Destructive ◽

Scanning Electron ◽

Surface Changes

Sufficient experience has been gained during the past five years to suggest an extended application of microreplication and scanning electron microscopy to problems of forensic science. The author's research was originally initiated with a view to develop a non-destructive method for identification of materials that went into objects of art, notably ivory and ivories. This was followed by a very specific application to the identification and duplication of the kinds of materials from animal teeth and tusks which two centuries ago went into the fabrication of the ivory dentures of George Washington. Subsequently it became apparent that a similar method of microreplication and SEM examination offered promise for a whole series of problems pertinent to art, technology and science. Furthermore, what began primarily as an application to solid substances has turned out to be similarly applicable to soft tissue surfaces such as mucous membranes and skin, even in cases of acute, chronic and precancerous epithelial surface changes, and to post-mortem identification of specific structures pertinent to forensic science.

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