Serial/Series Title
Country
States
Decade
Year
Month
Language
19,309 Matching Results
Results open in a new window/tab.
prev
Results:
19,297 - 19,309 of
19,309
Proton resonance spectroscopy
Preparations for studying [sup 30]P via [sup 29]Si(p,[gamma]) have continued. We are exploring both the use of the Fourier transform and the statistical behavior of electromagnetic transition strengths within the shell model as alternate approaches to identifying quantum chaos in nuclei. Analysis of interfering resonances in (p,[alpha]) resonances suggests that improvements in the limits on detailed balance in nuclear reactions are possible, but several issues still must be considered before a definitive conclusion can be reached. Plans for a new control system for the High Resolution Laboratory's electrostatic analyzer are being implemented.
Date:
November 1, 1992
Creator:
Shriner, J.F. Jr.
Object Type:
Report
System:
The UNT Digital Library
Photon resonance spectroscopy
This report summarizes the progress on Grant No. FG05-87ER40353 during the period February 1, 1990 to November 30, 1990. The primary focus of the research during this period has been on fluctuations of nuclear levels and possible connections with fundamental symmetries. In this paper the analysis of low-lying nuclear levels for a large collection of nuclides is discussed, and the analysis of just the levels in {sup 116}Sn is presented. The current status experiments to study fluctuation properties in {sup 30}P is summarized, while the development of hardware and software for the next phase of these measurements in outlined. We discuss the early stages of a project to search for a particular type of detailed-balance violation.
Date:
November 1, 1990
Creator:
Shriner, J.F. Jr.
Object Type:
Report
System:
The UNT Digital Library
Proton resonance spectroscopy. Progress report, December 1, 1990--November 30, 1991
This report discusses the following topics: Complete Level Scheme for {sup 30}P; A Search for Resonances Suitable for Tests of Detailed-Balance Violation; The Fourier Transform as a Tool for Detecting Chaos; Entrance Channel Correlations in p + {sup 27}Al; The Parity Dependence of Level Densities in {sup 49}V; and A Computer Program for the Calculation of Angular Momentum Coupling.
Date:
November 1, 1991
Creator:
Shriner, J. F. Jr.
Object Type:
Report
System:
The UNT Digital Library
Effects of the Operation of Hungry Horse Dam on the Kokanee Fishery in the Flathead River System, 1983 Annual Progress Report.
This study was undertaken to assess the effects of the operation of Hungry Horse Dam on the kokanee fishery in the Flathead River system. This annual report covers the 1982-1983 field season concerning the effects of Hungry Horse operations on kokanee abundance, migration, spawning, egg incubation and fry emergence in the Flathead River system. This report also addresses the expected recovery of the mainstem kokanee population under the flow regime recommended by the Department of Fish, Wildlife and Parks in 1982.
Date:
November 1, 1983
Creator:
Fraley, John J.
Object Type:
Report
System:
The UNT Digital Library
Proton resonance spectroscopy. Quarterly technical progress report, December 1992--November 1995
Work on chaos in the low-lying levels of nuclei has continued on several fronts. The major effort has been study of the {sup 29}Si(p,{gamma}) reaction with the goal of establishing a complete level scheme for {sup 30}P and analyzing the eigenvalue fluctuations for evidence of chaos. These measurements are in progress, and the current status is described. A related topic is the search for different signatures of chaos which do not require the extremely high degree of completeness and purity necessary for eigenvalue analyses; those efforts are discussed in Sections 2 and 3. The possibility of studying both parity violation and time-reversal invariance violation with charged particle resonances has been explored by performing calculations using experimentally measured resonance parameters. Large enhancements are indeed available; the results are discussed in Sections 4 and 5. Preparations for an experimental study of parity violation using these techniques are ongoing. An undergraduate project searching for experimental evidence of a parity dependence of level density is discussed in Section 6. A number of improvements to the operation of the TUNL KN accelerator have been implemented in the past three years. These are described in Section 7.
Date:
November 1, 1995
Creator:
Shriner, J.F. Jr.
Object Type:
Report
System:
The UNT Digital Library
Nuclear astrophysics with RIBs at Oak Ridge National Laboratory
The Daresbury Recoil Separator (DRS) and Silicon Detector Array (SIDAR) have been installed at Oak Ridge National Laboratory (ORNL) to perform measurements of reaction cross sections of astrophysical interest using radioactive ions beams (RIBs). For example radioactive {sup 17}F beams will be used to determine the {sup 14}O({alpha},p){sup 17}F and {sup 17}F(p,{gamma}){sup 18}Ne stellar reaction rates--both of which are important reactions in the Hot-CNO cycle. The first reactions studied will be {sup 1}H({sup 17}F,p){sup 17}F and {sup 1}H({sup 17}F,{alpha}){sup 14}O. These experiments will require {sup 17}F beams with intensities of 10{sup 4}--10{sup 6} ions per second in conjunction with the SIDAR. The {sup 1}H({sup 17}F,p){sup 17}F reaction will be used to probe resonances in {sup 18}Ne which contribute to the {sup 17}F(p,{gamma}){sup 18}Ne stellar reaction rate, while {sup 1}H({sup 17}F,{alpha}){sup 14}O will be used to determine the stellar reaction rate of the inverse reaction {sup 14}O({alpha},p){sup 17}F. In preparation for these experiments, measurements have been made of the {sup 1}H({sup 17}O,p){sup 17}O and {sup 1}H({sup 17}O,{alpha}){sup 14}N reaction cross sections. When higher beam currents of {sup 17}F become available, a direct measurement of the {sup 1}H({sup 17}F, {sup 18}Ne) resonance strength will be made using the DRS. To test the …
Date:
November 1, 1998
Creator:
Bardayan, D. W.
Object Type:
Article
System:
The UNT Digital Library
Proton resonance spectroscopy. Progress report, December 1, 1991--November 30, 1992
Preparations for studying {sup 30}P via {sup 29}Si(p,{gamma}) have continued. We are exploring both the use of the Fourier transform and the statistical behavior of electromagnetic transition strengths within the shell model as alternate approaches to identifying quantum chaos in nuclei. Analysis of interfering resonances in (p,{alpha}) resonances suggests that improvements in the limits on detailed balance in nuclear reactions are possible, but several issues still must be considered before a definitive conclusion can be reached. Plans for a new control system for the High Resolution Laboratory`s electrostatic analyzer are being implemented.
Date:
November 1, 1992
Creator:
Shriner, J. F. Jr.
Object Type:
Report
System:
The UNT Digital Library
Chemical activation of molecules by metals: Experimental studies of electron distributions and bonding. Progress report, March 1, 1992--September 30, 1992
Purpose of this research program is to obtain experimental information on the different fundamental ways metals bond and activate organic molecules. Our approach has been to directly probe the electronic interactions between metals and molecules through a wide variety of ionization spectroscopies and other techniques, and to investigate the relationships with bonding modes, structures, and chemical behavior. During this period, we have (1) characterized the electronic features of diphosphines and monophosphines in their coordination to metals, (2) carried out theoretical and experimental investigations of the bonding capabilities of C{sub 60} to transition metals, (3) developed techniques for the imaging of single molecules on gold substrates that emphasizes the electronic backbonding from the metal to the molecule, (4) obtained the high resolution photoelectron spectrum of pure C{sub 70} in the gas phase, (5) compared the bonding of {eta}{sup 3}- acetylide ligands to the bonding of other small organic molecules with metals, and (6) reported the photoelectron spectra and bonding of {eta}{sup 3}-cyclopropenyl groups to metals.
Date:
November 1, 1992
Creator:
Lichtenberger, D. L.
Object Type:
Report
System:
The UNT Digital Library
Approaches to verification of two-dimensional water quality models
The verification of a water quality model is the one procedure most needed by decision making evaluating a model predictions, but is often not adequate or done at all. The results of a properly conducted verification provide the decision makers with an estimate of the uncertainty associated with model predictions. Several statistical tests are available for quantifying of the performance of a model. Six methods of verification were evaluated using an application of the BETTER two-dimensional water quality model for Chickamauga reservoir. Model predictions for ten state variables were compared to observed conditions from 1989. Spatial distributions of the verification measures showed the model predictions were generally adequate, except at a few specific locations in the reservoir. The most useful statistics were the mean standard error of the residuals. Quantifiable measures of model performance should be calculated during calibration and verification of future applications of the BETTER model. 25 refs., 5 figs., 7 tabs.
Date:
November 1, 1990
Creator:
Butkus, S.R. (Tennessee Valley Authority, Chattanooga, TN (USA). Water Quality Dept.)
Object Type:
Report
System:
The UNT Digital Library
A Liquid-Scintillation Technique for the Radioassay of {sup 45}Ca
None
Date:
November 1, 1967
Creator:
Hardcastle, J. E.; Hannapel, R. J. & Fuller, W. H.
Object Type:
Article
System:
The UNT Digital Library
Sputtering calculations with the discrete ordinated method
The purpose of this work is to investigate the applicability of the discrete ordinates (S/sub N/) method to light ion sputtering problems. In particular, the neutral particle discrete ordinates computer code, ANISN, was used to calculate sputtering yields. No modifications to this code were necessary to treat charged particle transport. However, a cross section processing code was written for the generation of multigroup cross sections; these cross sections include a modification to the total macroscopic cross section to account for electronic interactions and small-scattering-angle elastic interactions. The discrete ordinates approach enables calculation of the sputtering yield as functions of incident energy and angle and of many related quantities such as ion reflection coefficients, angular and energy distributions of sputtering particles, the behavior of beams penetrating thin foils, etc. The results of several sputtering problems as calculated with ANISN are presented.
Date:
November 29, 1977
Creator:
Hoffman, T. J.; Dodds Jr., H. L.; Robinson, M.T. & Holmes, D.K.
Object Type:
Article
System:
The UNT Digital Library
History and evaluation of the AUTRC Program 1985--1995
The Alabama Universities/Tennessee Valley Authority Research Consortium (AUTRC), established in 1985, includes two state agencies and one federal agency working cooperatively with seven Alabama public research institutions to promote research and support economic development in Alabama. In 1985 the Alabama Department of Economic and Community Affairs (ADECA) was awarded a grant from the Appalachian Regional Commission (ARC) to establish a consortium of research universities and promote the economic development of the Appalachian counties of north Alabama. The following year, the Alabama Commission on Higher Education (ACHE) requested funding from the state legislature (Special Educational Trust Fund) to provide continuing support for AUTRC. One of the principal goals of this Consortium was to facilitate job creation in the state through the commercialization of TVA research. Since that time, continuing appropriations from ACHE and support from TVA, the universities, and the private sector have continued to support research activities and commercialization efforts. This report provides a ten-year overview of the program`s evolution, describes its research and commercialization activities, identifies the roles and contributions of the parties to the Consortium, and presents conclusions and recommendations for the future.
Date:
November 1, 1994
Creator:
Ransom, J. M. & Seale, S. K.
Object Type:
Report
System:
The UNT Digital Library
A Digital Computer Program for the Egcr Temperature and Neutron Transient Analysis--Etnata
None
Date:
November 18, 1963
Creator:
Keeton, D. C.
Object Type:
Report
System:
The UNT Digital Library