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Application of generalized classical trajectories in nuclear physics

Description: A new semi-classical method, the so-called uniform semiclassical approximation, is described briefly and then applied to two nuclear physics problems. The basic features of this method are that the dynamics of the problem is treated completely classically (that is, one solves classical equations of motion), but the quantum mechanical superposition principle is retained by evaluating a phase along the classical trajectory and adding probability amplitudes for indistinguishable processes rather t… more
Date: September 1, 1975
Creator: Leser, H.M.
Partner: UNT Libraries Government Documents Department
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Application of Monte Carlo criticality calculations to the Ames Laboratory Research Reactor

Description: >Thesis. The modeling of the Ames Laboratory Research Reactor core region and the input required to utilize the Monte Carlo computer code KENO for criticality calculations are described. Reactivity calculations in terms of k- effective were made for various reactor configurations and compared to measurements made on the actual reactor. (16 references) (auth)
Date: April 1, 1974
Creator: Hull, D.L.
Partner: UNT Libraries Government Documents Department
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Application of optimal prediction to molecular dynamics

Description: Optimal prediction is a general system reduction technique for large sets of differential equations. In this method, which was devised by Chorin, Hald, Kast, Kupferman, and Levy, a projection operator formalism is used to construct a smaller system of equations governing the dynamics of a subset of the original degrees of freedom. This reduced system consists of an effective Hamiltonian dynamics, augmented by an integral memory term and a random noise term. Molecular dynamics is a method for si… more
Date: December 1, 2004
Creator: Barber IV, John Letherman
Partner: UNT Libraries Government Documents Department
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Application of photothermal deflection spectroscopy to electrochemical interfaces

Description: This dissertation discusses the theory and practice of Photothermal Deflection Spectroscopy (PDS, which is also known as probe beam deflection spectroscopy, PBDS, probe deflection technique, and mirage effect spectroscopy) with respect to electrochemical systems. Much of the discussion is also relevant to non-electrochemical systems. PDS can measure the optical absorption spectrum of interfaces and concentration gradients in the electrolyte adjacent to the electrode. These measurements can be m… more
Date: March 1, 1992
Creator: Rudnicki, J. D.; McLarnon, F. R. & Cairns, E. J.
Partner: UNT Libraries Government Documents Department
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The application of psoralens to the study of DNA structure, function and dynamics

Description: A series of six nitroxide spin-labeled psoralens were designed, synthesized and tested as probes for DNA dynamics. The synthesis of these spin-labeled psoralen derivatives and their photoreactivity with double-stranded DNA fragments is described. The spin labels (nitroxides) were demonstrated to survive the uv irradiation required to bind the probe to the target DNA. EPR spectra of the photobound spin-labels indicate that they do not wobble with respect to the DNA on the time-scales investigate… more
Date: April 1, 1991
Creator: Spielmann, P. H.
Partner: UNT Libraries Government Documents Department
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Application of seismic tomographic techniques in the investigation of geothermal systems

Description: The utility of microearthquake data for characterizing the Northwest Geysers geothermal field and the Long Valley Caldera (LVC) was investigated. Three-dimensional (3-D) P- and S-wave seismic velocity models were estimated for the Coldwater Creek Steam Field (CCSF) in the Northwest Geysers region. Hypocenters relocated using these 3-D models appear to be associated with the steam producing zone, with a deeper cluster of hypocenters beneath an active injection well. Spatial and temporal patterns… more
Date: May 1, 1995
Creator: Romero, A. E., Jr.
Partner: UNT Libraries Government Documents Department
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Application of semiclassical methods to reaction rate theory

Description: This work is concerned with the development of approximate methods to describe relatively large chemical systems. This effort has been divided into two primary directions: First, we have extended and applied a semiclassical transition state theory (SCTST) originally proposed by Miller to obtain microcanonical and canonical (thermal) rates for chemical reactions described by a nonseparable Hamiltonian, i.e. most reactions. Second, we have developed a method to describe the fluctuations of decay … more
Date: November 1, 1993
Creator: Hernandez, R.
Partner: UNT Libraries Government Documents Department
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THE APPLICATION OF SINGLE PARTICLE AEROSOL MASS SPECTROMETRY FOR THE DETECTION AND IDENTIFICATION OF HIGH EXPLOSIVES AND CHEMICAL WARFARE AGENTS

Description: Single Particle Aerosol Mass Spectrometry (SPAMS) was evaluated as a real-time detection technique for single particles of high explosives. Dual-polarity time-of-flight mass spectra were obtained for samples of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX), and pentaerythritol tetranitrate (PETN); peaks indicative of each compound were identified. Composite explosives, Comp B, Semtex 1A, and Semtex 1H were also analyzed, and peaks due to the explosive components of each sam… more
Date: October 23, 2006
Creator: Martin, A
Partner: UNT Libraries Government Documents Department
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Application of Soft X-Ray Appearance Potential Spectroscopy to Light Lanthanides, 4d Transition Metals, and Insulators

Description: Evaporated films of La, Ce, Yb, Y, Ag--Mn(5 percent), KCl, MnF$sub 2$, CsCl and LaF$sub 3$ were studied using the soft x-ray appearance potential spectroscopy (SXAPS) technique. Studies were also made of bulk polycrystalline samples of Y, Zr, Nb, and Mo. The results are discussed in terms of existing SXAPS theories. Several similarities between soft x-ray absorption (SXA) data and the SXAPS results are discussed, and it is shown that the SXA data can aid in the interpretation of SXAPS spectra w… more
Date: October 1, 1975
Creator: Smith, R. J.
Partner: UNT Libraries Government Documents Department
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The application of solid-state NMR spectroscopy to electrochemical systems: CO adsorption on Pt electrocatalysts at the aqueous-electrode interface

Description: A fuel cell is an electrochemical energy conversion device, the continuous-flow analogue of the popular electrochemical storage device known as the battery. While the potential of fuel cells as power sources was recognized well over a century ago, they have since found limited application; a myriad of chemical, engineering and materials issues can be cited for this disappointing showing. Recent growing concern over the fate of the environment, however, has helped to renew interest in fuel cell … more
Date: December 1, 1996
Creator: Yahnke, M. S.; Reimer, J. A. & Cairns, E. J.
Partner: UNT Libraries Government Documents Department
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The Application of Some Hartree-Fock Model Calculation to the Analysis of Atomic and Free-Ion Optical Spectra

Description: Techniques for applying ab-initio calculations to the is of atomic spectra are investigated, along with the relationship between the semi-empirical and ab-initio forms of Slater-Condon theory. Slater-Condon theory is reviewed with a focus on the essential features that lead to the effective Hamiltonians associated with the semi-empirical form of the theory. Ab-initio spectroscopic parameters are calculated from wavefunctions obtained via self-consistent field methods, while multi-configuration … more
Date: August 6, 1980
Creator: Hayhurst, Thomas Laine
Partner: UNT Libraries Government Documents Department
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Application of spectral hole burning to the study of in vitro cellular systems

Description: Chapter 1 of this thesis describes the various stages of tumor development and a multitude of diagnostic techniques used to detect cancer. Chapter 2 gives an overview of the aspects of hole burning spectroscopy important for its application to the study of cellular systems. Chapter 3 gives general descriptions of cellular organelles, structures, and physical properties that can serve as possible markers for the differentiation of normal and cancerous cells. Also described in Chapter 3 are the p… more
Date: November 8, 1999
Creator: Milanovich, Nebojsa
Partner: UNT Libraries Government Documents Department
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Application of the Environmental Protection Agency`s data quality objective process to environmental monitoring quality control

Description: The United States Environmental Protection Agency`s (EPA) Data Quality Objectives (DQO) process was applied to two environmental monitoring networks for the purpose of optimizing field quality control sampling to give the highest quality monitoring data with minimal impact on resources. The DQO process, developed primarily to aid in cleanup and restoration activities, is a systematic approach to designing sampling, and analysis programs with improved efficiency, cost savings, and measureable an… more
Date: November 1, 1995
Creator: Garcia, L.M.
Partner: UNT Libraries Government Documents Department
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Application of the Scenario Planning Process - a Case Study: The Technical Information Department at the Lawrence Livermore National Laboratory

Description: When the field of modern publishing was on a collision course with telecommunications, publishing organizations had to come up to speed in fields that were, heretofore, completely foreign and technologically forbidding to them. For generations, the technology of publishing centered on offset lithography, typesetting, and photography--fields that saw evolutionary and incremental change from the time of Guttenberg. But publishing now includes making information available over the World Wide Web--… more
Date: November 26, 2001
Creator: Schuster, J A
Partner: UNT Libraries Government Documents Department
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The application of the symmetry properties of optical second harmonic generation to studies of interfaces and gases

Description: Optical second harmonic generation has proven to be a powerful tool for studying interfaces. The symmetry properties of the process allow for surface sensitivity not available with other optical methods. In this thesis, we take advantage of these symmetry properties SHG to study a variety of interesting systems not previously studied with this technique. We show that optical second harmonic generation is an effective surface probe with a submonolayer sensitivity for media without inversion symm… more
Date: November 1, 1991
Creator: Feller, M. B.
Partner: UNT Libraries Government Documents Department
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Application of Ultrasonic Guided Waves to the Characterization of Texture in Metal Sheets of Cubic and Hexagonal Crystallites

Description: Ultrasonic techniques have recently been applied to the texture characterization in polycrystalline aggregates of hexagonal crystals. The basis of this application lies in the relations between the elastic constants {bar C}{sub ij} of the aggregates, which can be inferred from ultrasonic wave velocity measurements, and the orientation distribution coefficients. This communication present such relations for aggregates which possess orthotopic material symmetry and hexagonal crystal symmetry for … more
Date: October 8, 1990
Creator: Li, Yan
Partner: UNT Libraries Government Documents Department
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Applications of a single-molecule detection in early disease diagnosis and enzymatic reaction study

Description: Various single-molecule techniques were utilized for ultra-sensitive early diagnosis of viral DNA and antigen and basic mechanism study of enzymatic reactions. DNA of human papilloma virus (HPV) served as the screening target in a flow system. Alexa Fluor 532 (AF532) labeled single-stranded DNA probes were hybridized to the target HPV-16 DNA in solution. The individual hybridized molecules were imaged with an intensified charge-coupled device (ICCD) in two ways. In the single-color mode, target… more
Date: October 15, 2008
Creator: Li, Jiangwei
Partner: UNT Libraries Government Documents Department
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Applications of capillary electrophoresis and laser-induced fluorescence detection to the analysis of trace species: From single cells to single molecules

Description: This Ph.D. Thesis describes several separation and detection schemes for the analysis of small volume and amount of samples, such as intracellular components and single enzymes developed during research. Indirect Laser-induced fluorescence detection and capillary electrophoresis were used to quantify lactate and pyruvate in single red blood cells. The assay of specific enzyme activities was achieved by monitoring the highly fluorescent enzymatic reaction product, NADH. LDH activity was found no… more
Date: November 1, 1995
Creator: Qifeng, X.
Partner: UNT Libraries Government Documents Department
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Applications of electrochemically-modulated liquid chromatography (EMLC): Separations of aromatic amino acids and polycyclic aromatic hydrocarbons

Description: The research in this thesis explores the separation capabilities of a new technique termed electrochemically-modulated liquid chromatography (EMLC). The thesis begins with a general introduction section which provides a literature review of this technique as well as a brief background discussion of the two research projects in each of the next two chapters. The two papers which follow investigate the application of EMLC to the separation of a mixture of aromatic amino acids and of a mixture of … more
Date: March 27, 1998
Creator: Deng, L.
Partner: UNT Libraries Government Documents Department
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Applications of Flavor Symmetry to the Phenomenology of Elementary Particles

Description: Some applications of flavor symmetry are examined. Approximate flavor symmetries and their consequences in the MSSM (Minimal Supersymmetric Standard Model) are considered, and found to give natural values for the possible B- and L-violating couplings that are empirically acceptable, except for the case of proton decay. The coupling constants of SU(3) are calculated and used to parameterize the decays of the D mesons in broken flavor SU(3). The resulting couplings are used to estimate the long-d… more
Date: May 1, 1995
Creator: Kaeding, T. A.
Partner: UNT Libraries Government Documents Department
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