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The other high resolution post accelerator approach (open access)

The other high resolution post accelerator approach

There has been significant discussion in consideration of a high resolution mass separator followed by a RFQ and a linear accelerator as the basic format for IsoSpin Laboratory. There exists another strong possibility-namely a low-resolution mass separator coupled to a cyclotron. The major objection to this approach has been that the conversion from the +1 mass separator beam to a q/m beam of 1/4 to 1/3 is thought to be highly inefficient. Since we are in the fortunate position of having the two expensive components of this system available for tests (an on-line mass separator and an ECR source), we intend to couple these devices to actually measure these efficiencies and to test ideas for improving the efficiency. We present some specifics of this approach.
Date: May 24, 1993
Creator: Moltz, D. M.; Tighe, R. J.; Rowe, M. W.; Ognibene, T. J. & Cerny, J.
System: The UNT Digital Library
Single sided tomography of extremely large dense objects (open access)

Single sided tomography of extremely large dense objects

One can envision many circumstances where radiography could be valuable but is frustrated by the geometry of the object to be radiographed. For example, extremely large objects, the separation of rocket propellants from the skin of solid fuel rocket motor, the structural integrity of an underground tank or hull of a ship, the location of buried objects, inspection of large castings etc. The author has been investigating ways to do this type of radiography and as a result has developed a technique which can be used to obtain three dimensional radiographs using Compton scattered radiation from a monochromatic source and a high efficiency, high resolution germanium spectrometer. This paper gives specific details of the reconstruction technique and presents the results of numerous numerical simulations and compares these simulations to spectra obtained in the laboratory. In addition the author presents the results of calculations made for the development of an alternative single sided radiography technique which will permit inspection of the interior of large objects. As a benchmark the author seeks to obtain three dimensional images with a resolution of about one cubic centimeter in a concrete cube 30 centimeters on a side. Such a device must use photons of very …
Date: March 24, 1993
Creator: Thoe, R. S.
System: The UNT Digital Library
High resolution tomography of objects with access to a single side (open access)

High resolution tomography of objects with access to a single side

The author is developing a technique which will enable one to obtain high-contrast, high-spatial resolution, three-dimensional images in opaque objects. The only constraint will be the radiation source and detector(s) will be located on the same side of the object. The goal is to obtain images with a spatial resolution of {approximately}1 mm at depths of 10 mm and {approximately}3 mm at depths of 30 mm in materials of moderate density (brass, steel, etc.). The author`s technique uses a highly-collimated beam of monochromatic gamma rays and a slit collimated high-resolution, high-efficiency, coaxial germanium spectrometer. If the geometry is well known, the spectrum of Compton scattered radiation can be used to map out the density as a function of depth. By scanning the object in two dimensions, a full three-dimensional image of the electron density can be reconstructed. The resolution is dependent on the incident beam collimation and the energy resolution of the spectrometer. For his system, the author anticipates a resolution of about 1 mm{sup 3}. The apparatus, reconstruction algorithms and current data verifying his predictions are presented here. Also included are the details on how the system can be modified to increase the efficiency by over two orders of …
Date: March 24, 1993
Creator: Thoe, R. S.
System: The UNT Digital Library
Organizing for public involvement in Fernald decision-making (open access)

Organizing for public involvement in Fernald decision-making

Fernald is returning to the basics of interpersonal communication as a cornerstone of its public involvement program. The guiding premise behind this concept is the belief that face-to-face interaction between people is more likely to build trust and confidence than public meetings, news releases and other traditional public information techniques. A network of project spokespersons, called ``envoys,`` is being organized to develop person-to-person relationships with people interested in the future of Fernald. To support this approach, public affairs personnel are adopting roles as management consultants and communications coaches in addition to serving in their traditional role as public information specialists. Early observations seem to show signs of improvement in the level of public trust in Fernald decision-makers.
Date: October 24, 1993
Creator: Morgan, K. L. & Hoopes, J.
System: The UNT Digital Library
Low toxicity aromatic diamine curing agents for adhesives (open access)

Low toxicity aromatic diamine curing agents for adhesives

Increasing severity of regulations for handling of hazardous materials has led to formulation of adhesives with considerably lowered toxicities for use at the Oak Ridge Y-12 Plant. Fundamental was the development of Asilamine aromatic diamines, a family of liquid aromatic diamines useful as substitutes for methylenedianiline (MDA), a widely used adhesives curing agent. The use of Asilamine has allowed us to continue operations without dealing with expensive measures for regulation of MDA as a carcinogen promulgated by the Occupational Safety and Health Administration (OSHA).
Date: August 24, 1993
Creator: Dorsey, G. F.
System: The UNT Digital Library
Radio galaxies and their environment (open access)

Radio galaxies and their environment

The relationships between radio galaxies and their environment are varied, complex, and evolve with cosmic epoch. Basic questions are what role the environment plays in triggering and fuelling (radio) galaxy activity what the effects of this activity are on its environment, and how radio galaxies and environment evolve. Clearly, this could be the topic of a workshop all in itself and the scope of this review will necessarily be limited. A review of the connections between environment and galaxy activity in general has been given by Heckman. First, I will briefly summarize the relationships between parent galaxy and cluster environments, and radio galaxies. A more detailed discussion of various aspects of this will be given elsewhere by F. Owen, J.0. Burns and R. Perley. I will then discuss the current status of investigations of extended emission-line regions in radio galaxies, again referring elsewhere in this volume for more detailed discussions of some particular aspects (kinematics and ionization mechanisms by K. Meisenheimer; polarization and spectral index lobe asymmetries by G. Pooley). I will conclude with a brief discussion of the current status of observations of high redshift radio galaxies.
Date: February 24, 1993
Creator: van Breugel, W.
System: The UNT Digital Library