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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Coincident proton decay of the continuum induced by 200 MeV protons on 12C

Pilcher, John Victor January 1989 (has links)
Bibliography: p. 212-221. / Coincident protons from the reaction ¹²C(p,2p) at an incident proton energy of 200 Me V, have been measured using conventional particle telescopes. Data were acquired at nine pairs of angles (θ₂=20°, 45°, 70°, 95°, 120° and 145° for θ₁ =-20°, and θ₂=35°, 85° and 135° for θ₁ =-45°). An improved model, based on previous theoretical and experimental work, has been proposed to describe the reaction mechanism leading to the observed coincident proton yield from the nuclear continuum. This model considers an initial quasifree nucleon-nucleon interaction - described by a distorted wave impulse approximation (DWIA) treatment - between the incident proton and a single target nucleon, followed by the rescattering of the struck nucleon, which behaves as an intranuclear projectile, from the spectator part of the target nucleus. The validity of the DWIA treatment used in the continuum study, has been tested by analysing the kinematic regions of the coincident proton energy spectra corresponding to the knockout of protons from the outer lp3/2 orbital of ¹²C which do not undergo further interactions with the residual nucleus. Good agreement in shape has been found between the calculated and measured cross sections in the kinematic region of interest to the continuum study. An average spectroscopic factor of 1.1±0.3 was extracted. Except in the -20°,20° case, the DWIA treatment was found to be insensitive to the choice of the initial or final energy prescriptions for the two-body scattering approximation. Nonlocality effects were found to be small, changing the absolute value of spectroscopic factors by a maximum of 20%. Coincident continuum cross sections were extracted from the experimental data corresponding to the detection of protons at the θ₁ angles with energies of 70±5 MeV, 100±5 MeV and 130±5 MeV. Comparisons were made with calculations which modelled the proposed reaction mechanism in terms of a convolution integral over the DWIA cross sections describing the initial quasifree knockout process and experimental inelastic scattering probabilities describing the further multiple scattering interactions undergone by the knocked out nucleons. Good agreement has been found between the normalized calculated and measured continuum cross sections (spectroscopic factors varying from 0.8 to 2.3 between sets of data, depending on the kinematic region sampled and the prescription used for the two-body scattering approximation). It has been shown that contributions from nucleons that are knocked out both in- and out-of-plane in the initial quasifree process should be considered, and that the contribution from neutron knockout in the initial interaction is significant, ranging from 0.13 to 0.62 that of the proton knockout contribution.
102

Assessment of Volatile Metabolites for In Situ Detection of Fungal Decay of Wood

Maafi, Nasim 11 August 2017 (has links)
Although incipient fungal decay of wood may be difficult to detect early, it causes a significant decrease in wood strength. Developing a reliable method of decay identifica-tion to overcome wood replacement costs by non-destructive methods is necessary. This study investigates a possibility of identifying fungal volatile organic compounds (VOCs) as means of fungal detection using solid phase micro-extraction (SPME) coupled with gas chromatography–mass spectrometry (GC-MS). Volatile emissions from two brown rot (Gloeophyllum trabeum and Postia pla-centa) and two white rot (Trametes versicolor and Irpex lacteus) fungi on pine and aspen and their profiles related to wood mechanical strength and mass loss were investigated over 12 weeks. Principal component analysis of VOCs spectra differentiated volatiles from decayed and sound wood. Volatiles from two fungal species revealed distinct pat-terns of early and late degradation stages. SPME combined with GC-MS showed promissing results for non-destructive identification of incipient decay in wood struc-tures.
103

Decay properties of unstable Gd nuclides

Turcotte, Richard January 1988 (has links)
No description available.
104

Exclusive decay modes of heavy mesons in perturbative quantum chromodynamics

Trottier, Howard D. January 1984 (has links)
No description available.
105

Level structure of neutron-deficient Br isotopes.

Houdayer, Alain. January 1972 (has links)
No description available.
106

A search for the decays B⁺ [arrow] l⁺[nu] and B⁰ [arrow] l⁺ [tau]⁻ (l = e, [mu]) using hadronic tag reconstruction /

Klemetti, Miika A. January 2007 (has links)
No description available.
107

The decay of K43 /

Burns, Kerry Ian. January 1975 (has links)
No description available.
108

A Correlation of the Habitat Factors with the Quantity of Bacterial Colonies as Observed by the Direct Microscopic Method on Twenty Soils of Denton County, Texas

Roach, Cornelia Ann 08 1900 (has links)
The aim of this study is to determine what factors are most important in controlling the number of bacterial colonies found in twent represntative Denton County (Texas) soils during the growing season.
109

The Decay of ¹⁸⁵Os

Cook, William Brian 09 1900 (has links)
The decay of 94 day ¹⁸⁵Os to levels in ¹⁸⁵Re has been studied, using Ge(Li), NaI(Tl), and Si(Li) detectors. The internal conversion spectrum was investigated using the Chalk River 𝛑√2 β-spectrometer. The decay scheme is discussed and some spin assignments are suggested. / Thesis / Master of Science (MSc)
110

Rare earth nuclides far from beta stability

Deslauriers, Jean. January 1979 (has links)
Note:

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