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Neutron activation analysis and chemical inference for the identification of Buena Vista ceramicsSullivan, Daniel D. 01 January 1986 (has links)
Instrumental Neutron Activation Analysis was used for this study of stonewares collected from the site of the Buena Vista/Oregon Pottery Company (1866-1890).
The results show significant chemical signatures in the samples tested. Thorium/ytterbium and thorium/chromium ratios within their respective ranges of variation demonstrate a relative conformity among all samples of Buena Vista ceramics.
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Application of inversion techniques to radiometric dataWilliams, Kevin M. (Kevin McEachern) January 1983 (has links)
No description available.
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Plutonic and volcanic rocks from central Chile (33 ̊- 42 ̊S) : geochemical evidence regarding their petrogenesis.Lopez Escobar, Leopoldo January 1975 (has links)
Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Earth and Planetary Sciences. / Vita. / Bibliography: leaves 123-135. / Ph.D.
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A neutron activation analysis investigation of traceable elements from automobile exhaust in roadside soil and vegetationOakes, Thomas Wyatt 08 June 2010 (has links)
The purpose of this work was to demonstrate the effectiveness of neutron activation analysis in studying a complex environmental problem. The area chosen for study was the exhaust emitted by automobiles and its dispersion into soil and selected plants near highways. The elements chosen for this study were the major traceable components of gasoline and automobile exhaust. Variations in the concentrations of these trace elements in soil, grass and wash off the grass at various distances from two highways were investigated. Of the elements found in gasoline and in automobile exhaust, bromine most clearly indicated where some of the atmospheric components were going and, therefore, would be the most suitable element for neutron activation studies of atmospheric and turbulence modeling and possibly for following biological effects of automobile traffic. / Master of Science
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Design, construction, and characterization of a neutron depth profiling facility at the Oregon State University TRIGA�� reactor with an advanced digital spectroscopy systemRobinson, Joshua A. 13 July 2012 (has links)
In this work, Neutron Depth Profiling (NDP) analysis capability has been added to the Oregon State University TRIGA�� Reactor Prompt Gamma Neutron Activation Analysis Facility (PGNAA). This system has been implemented with an advanced digital spectroscopy system and is capable of rise time pulse shape analysis as well as coincidence measurements from multiple detectors. The digital spectroscopy system utilizes a high-speed multichannel digitizer with speeds up to 200 Megasamples/second (MS/s) with advanced hardware trigger and time stamping capabilities. These additions allow the facility to conduct simultaneous NDP and PGNAA combined measurements, which also enables cross calibration. The digital pulse processing is implemented with software programmed rise time pulse shape analysis capabilities for the analysis of the detector responses on a pulse-by-pulse basis to distinguish between different interactions in the detector. The advanced trigger capabilities of the digitizer were configured to accurately measure and correct for dead time effects from pulse pile up and preamplifier decay time. / Graduation date: 2013
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Quantification of trace metals in an adsorbent using proton induced x-ray emissionYadav, Nirbhay Narayan. January 2005 (has links)
Thesis (M.Sc.)(Hons) -- University of Western Sydney, 2005. / "A thesis presented to the University of Western Sydney in fulfilment of the requirements for the degree of Master of Science (Honours) Physics" Bibliography: leaves 101-108.
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Elemental analysis of some geological samples using neutron activation techniqueAsres Yihunie Hibstie 09 May 2013 (has links)
This study describes the technique and procedures used for the simultaneous determination
of elements involved in Instrumental Neutron Activation Analysis, applied
to some geological samples as a sensitive and non-destructive tool. Using Isotopic
Neutron Source, the delayed gamma-rays emitted due to neutron capture have been
applied for the investigation of the elemental constituents and concentrations of major,
minor and trace elements in such samples.
The experimental investigations were carried out at the scale of researcher's practices
at the chosen site by measuring soil/rock nutrient contents from hydrologically
isolated farmland/site plots. Using detailed sampling procedures with special precautions,
against contaminations, to yield meaningful results, soil/rock samples have
been collected from selected areas of East Gojjam, pulverized, homogenized and prepared
for irradiation.
The samples were properly prepared together with known standards of potassium iodide
or cupric sulphate or arsenic trioxide (one /or both at a time), and simultaneously
irradiated in to isotopic neutron
ux in the same irradiation position. After activation,
the samples were subjected to gamma-ray spectrometry, using a high-purity germanium
detection system and computerized multichannel analyzer. The gamma-ray
spectra from the irradiated samples were measured by high resolution gamma-ray
spectrometry with a calibrated germanium detector. Both qualitative and quantitative
approach to data collection and analysis were used in order to gain insight into what should be acceptable to the community.
The results obtained have a practical interest in view of possible applications to the
technology of extraction and exploration of a variety of industrial, metallic, cement
minerals, and geothermal energy and coal deposits. These results tend to agree with
the lowest values reported in the literature, and the analytical precision is su cient
for the determination of the standard deviation of the distribution of all elements in
East Gojjam and these results were brie
y discussed within the text of this research
work.
In carrying out the analysis, the best and most convenient method being the Instrumental
and /non-destructive Neutron Activation Analysis was adopted, and NAA
has matured and attained analytical competence providing not only rapid, quantitative,
qualitative, simultaneous, multielement analysis but also crucial validation
support to programmes using di erent analytical techniques. This method of analysis
is generally multi-element and experimental conditions can be designed to be
nondestructive to the sample, and it plays a leading role among analytical techniques
in the eld of environmental research related to human, animal and plant
health.
Studies of di erent radionuclide and trace elements in the environmental samples are
very important for health physics, research and education. Many forms of elements
are possible in environmental samples which may be hazardous for human being, animals
and also plants. Most of them have the potential for both benefcial and harmful
effects / Environmental Sciences / D. Phil. (Environmental Science)
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Elemental analysis of some geological samples using neutron activation techniqueAsres Yihunie Hibstie 09 May 2013 (has links)
This study describes the technique and procedures used for the simultaneous determination
of elements involved in Instrumental Neutron Activation Analysis, applied
to some geological samples as a sensitive and non-destructive tool. Using Isotopic
Neutron Source, the delayed gamma-rays emitted due to neutron capture have been
applied for the investigation of the elemental constituents and concentrations of major,
minor and trace elements in such samples.
The experimental investigations were carried out at the scale of researcher's practices
at the chosen site by measuring soil/rock nutrient contents from hydrologically
isolated farmland/site plots. Using detailed sampling procedures with special precautions,
against contaminations, to yield meaningful results, soil/rock samples have
been collected from selected areas of East Gojjam, pulverized, homogenized and prepared
for irradiation.
The samples were properly prepared together with known standards of potassium iodide
or cupric sulphate or arsenic trioxide (one /or both at a time), and simultaneously
irradiated in to isotopic neutron
ux in the same irradiation position. After activation,
the samples were subjected to gamma-ray spectrometry, using a high-purity germanium
detection system and computerized multichannel analyzer. The gamma-ray
spectra from the irradiated samples were measured by high resolution gamma-ray
spectrometry with a calibrated germanium detector. Both qualitative and quantitative
approach to data collection and analysis were used in order to gain insight into what should be acceptable to the community.
The results obtained have a practical interest in view of possible applications to the
technology of extraction and exploration of a variety of industrial, metallic, cement
minerals, and geothermal energy and coal deposits. These results tend to agree with
the lowest values reported in the literature, and the analytical precision is su cient
for the determination of the standard deviation of the distribution of all elements in
East Gojjam and these results were brie
y discussed within the text of this research
work.
In carrying out the analysis, the best and most convenient method being the Instrumental
and /non-destructive Neutron Activation Analysis was adopted, and NAA
has matured and attained analytical competence providing not only rapid, quantitative,
qualitative, simultaneous, multielement analysis but also crucial validation
support to programmes using di erent analytical techniques. This method of analysis
is generally multi-element and experimental conditions can be designed to be
nondestructive to the sample, and it plays a leading role among analytical techniques
in the eld of environmental research related to human, animal and plant
health.
Studies of di erent radionuclide and trace elements in the environmental samples are
very important for health physics, research and education. Many forms of elements
are possible in environmental samples which may be hazardous for human being, animals
and also plants. Most of them have the potential for both benefcial and harmful
effects / Environmental Sciences / D. Phil. (Environmental Science)
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Establishment of concentration ratios for riparian and shrub steppe areas of the eastern Washington Columbia basinNapier, Jonathan Bamberger 12 September 2012 (has links)
Concentration ratios are used to determine the transfer of nuclides from soil to biota to fauna. Some nuclides have limited associated data though, this has not prevented predictions from being performed at sites without associated data. These ratios are site specific and are not fully applicable when applied to other locations. A recent literature review for a waste repository performance assessment determined that a significant portion of the environmental data was based on recursively published material. To address this deficiency neutron activation analysis (NAA) was used to determine concentration ratios of certain biota. Three sites, two riparian and one shrub steppe, were sampled in the eastern Washington Columbia basin, near the Hanford site. Two hundred and fifty eight samples of opportunity were collected. This included 15 soil samples, 10 water and sediment samples, 40 different species of biota, and 2 terrestrial animal species and 3 aquatic animal species. These samples were prepared for NAA by drying, weighing, and in certain cases ashing to improve detection efficiency. After activation, the samples were placed in a HPGe detector to perform spectral analysis. The concentration results of 26 elements of interest are presented, along with newly established concentration ratios for all of the species sampled. / Graduation date: 2013
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Etudes expérimentales de l'accélération de particules avec des lasers ultra-intenses : applications à des expériences de physique nucléaire dans les plasmas lasersPlaisir, Cyril 23 November 2010 (has links) (PDF)
Les lasers de puissance permettent depuis une dizaine d'années de produire des faisceaux de particules accélérées dans lesquels quelques 1012 électrons, protons sont accélérés en quelques ps. Nous avons simulé et développé des diagnostiques, utilisant l'activation nucléaire, pour qualifier les distributions angulaire et en énergie des faisceaux de particules générés. Les techniques de caractérisation sont présentées et illustrées à l'aide des résultats obtenus dans différentes expériences réalisées auprès des lasers de puissance. Nous envisageons d'utiliser ces faisceaux pour exciter des états nucléaires dans des environnements plasma. Celui-ci peut en effet influencer des caractéristiques intrinsèques du noyau comme la durée de vie de certains états isomériques. Dans le cadre de la préparation de telles expériences, nous avons mesuré la section efficace de la réaction (g,n) permettant de produire l'état isomérique du 84Rb à 463 keV d'énergie d'excitation, à l'aide de l'accélérateur ELSA du CEA/DIF de Bruyères-le-Châtel.
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