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A Scaled Final Focus Experiment for Heavy Ion Fusion

Description: A one-tenth dimensionally scaled version of a final focus sub-system design for a heavy ion fusion driver is built and tested. By properly scaling the physics parameters that relate particle energy and mass, beam current, beam emittance, and focusing field, the transverse dynamics of a driver scale final focus are replicated in a small laboratory beam. The experiment uses a 95 {micro}A beam of 160 keV Cs{sup +} ions to study the dynamics as the beam is brought to a ballistic focus in a lattice … more
Date: September 19, 2000
Creator: MacLaren, Stephan, Alexander
Partner: UNT Libraries Government Documents Department
open access

NIF program management

Description: No Description Available.
Date: September 15, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

NIF frequently asked questions

Description: The Stockpile Stewardship Program is an initiative to maintain the nuclear deterrent of the United States in the post-Cold War era. It is based on the maintenance of our stockpile through an ongoing process of surveillance, assessment, refurbishment, and recertification, without nuclear testing. At the heart of the SSP is an attempt to bring advanced experimental and computational tools to bear on the evaluation and certification of the stockpile itself; these advanced scientific capabilities a… more
Date: September 15, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

NIF and science

Description: The National Ignition Facility (NIF) will have many uses besides its primary mission in the US Department of Energy's Stockpile Stewardship Program. It will provide a broad array of applications to basic science, and will also play an important role in the development of commercial fusion energy.
Date: September 15, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

Kinetics of (beta)(right arrow)(delta) Solid-Solid Phase Transition of HMX

Description: In order to calculate the kinetic parameters from DSC data, we have used the generally accepted methods of Bershtein [13]. We have calculated the rate constants for 4 temperatures and the activation energy based on the shift in the transition temperature, {beta} {yields} {delta} for HMX. The values of E{sub a} from this work is 402 kJ/mol compared to previous results by Brill [9] of 204 kJ/mol. Brill and associates measured the phase transition of HMX using FTIR, sodium chloride plates and sili… more
Date: September 1, 2000
Creator: Weese, R K
Partner: UNT Libraries Government Documents Department
open access

NIF facts

Description: The National Ignition Facility (NIF) will use the world's largest laser to compress and heat BB-sized capsules of fusion fuel to thermo-nuclear ignition. NIF experiments will produce temperatures and densities like those in the Sun or in an exploding nuclear weapon. The experiments will help scientists sustain confidence in the nuclear weapon stockpile without nuclear tests as a unique element of the DOE'S Stockpile Stewardship Program and will produce additional benefits in basic science and f… more
Date: September 8, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

Towards Chip Scale Liquid Chromatography and High Throughput Immunosensing

Description: This work describes several research projects aimed towards developing new instruments and novel methods for high throughput chemical and biological analysis. Approaches are taken in two directions. The first direction takes advantage of well-established semiconductor fabrication techniques and applies them to miniaturize instruments that are workhorses in analytical laboratories. Specifically, the first part of this work focused on the development of micropumps and microvalves for controlled f… more
Date: September 21, 2000
Creator: Ni, J.
Partner: UNT Libraries Government Documents Department
open access

Multi-atom resonant photoemission and the development of next-generation software and high-speed detectors for electron spectroscopy

Description: This dissertation has involved the exploration of a new effect in photoelectron emission, multi-atom resonant photoemission (MARPE), as well as the development of new software, data analysis techniques, and detectors of general use in such research. We present experimental and theoretical results related to MARPE, in which the photoelectron intensity from a core level on one atom is influenced by a core-level absorption resonance on another. We point out that some of our and others prior experi… more
Date: September 1, 2000
Creator: Kay, Alexander William
Partner: UNT Libraries Government Documents Department
open access

Fidelity of a Finite Element Model for Longitudinal Wave Propagation in Thick Cylindrical Wave Guides

Description: The ability to model wave propagation in circular cylindrical bars of finite length numerically or analytically has many applications. In this thesis the capability of an explicit finite element method to model longitudinal waves in cylindrical rods with circular cross-sections is explored. Dispersion curves for the first four modes are compared to the analytical solution to determine the accuracy of various element sizes and time steps. Values for the time step and element size are determined … more
Date: September 1, 2000
Creator: Puckett, A.D.
Partner: UNT Libraries Government Documents Department
open access

New perspectives in physics beyond the standard model

Description: In 1934 Fermi postulated a theory for weak interactions containing a dimensionful coupling with a size of roughly 250 GeV. Only now are we finally exploring this energy regime. What arises is an open question: supersymmetry and large extra dimensions are two possible scenarios. Meanwhile, other experiments will begin providing definitive information into the nature of neutrino masses and CP violation. In this paper, we explore features of possible theoretical scenarios, and study the phenomenol… more
Date: September 9, 2000
Creator: Weiner, Neal Jonathan
Partner: UNT Libraries Government Documents Department
open access

Characterization of the Dilute Ising Antiferromagnet

Description: A spin glass is a magnetic ground state in which ferromagnetic and antiferromagnetic exchange interactions compete, thereby creating frustration and a multidegenerate state with no long range order. An Ising system is a system where the spins are constrained to lie parallel or antiparallel to a primary axis. There has been much theoretical interest in the past ten years in the effects of applying a magnetic field transverse to the primary axis in an Ising spin glass at low temperatures and thus… more
Date: September 12, 2000
Creator: Wiener, T.
Partner: UNT Libraries Government Documents Department
open access

Development and Evaluation of an Externally Air-Cooled Low-Flow torch and the Attenuation of Space Charge and Matrix Effects in Inductively Coupled Plasma Mass Spectrometry

Description: An externally air-cooled low-flow torch has been constructed and successfully demonstrated for applications in inductively coupled plasma mass spectrometry (ICP-MS). The torch is cooled by pressurized air flowing at {approximately}70 L/min through a quartz air jacket onto the exterior of the outer tube. The outer gas flow rate and operating RF forward power are reduced considerably. Although plasmas can be sustained at the operating power as low as 400 W with a 2 L/min of outer gas flow, somewh… more
Date: September 12, 2000
Creator: Praphairaksit, N.
Partner: UNT Libraries Government Documents Department
open access

Transition Metal Complexes of Cr, Mo, W and Mn Containing {eta}{sup 1}(S)-2,5-Dimethylthiophene, Benzothiophene and Dibenzothiophene Ligands

Description: The UV photolysis of hexanes solutions containing the complexes M(CO){sub 6} (M=Cr, Mo, W) or CpMn(CO){sub 3} (Cp={eta}{sup 5}-C{sub 5}H{sub 5}) and excess thiophene (T{sup *}) (T{sup *}=2,5-dimethylthiophene (2,5-Me{sub 2}T), benzothiophene (BT), and dibenzothiophene (DBT)) produces the {eta}{sup 1}(S)-T{sup *} complexes (CO){sub 5}M({eta}{sup 1}(S)-T{sup *}) 1-8 or Cp(CO){sub 2}Mn({eta}{sup 1}(S)-T{sup *})9-11, respectively. However, when T{sup *}=DBT, and M=Mo, a mixture of two products resu… more
Date: September 21, 2000
Creator: Reynolds, M.
Partner: UNT Libraries Government Documents Department
open access

Multichannel Simultaneous Determination of Activities of Lactate Dehydrogenase

Description: It is very important to find the best conditions for some enzymes to do the best catalysis in current pharmaceutical industries. Based on the results above, we could say that this set-up could be widely used in finding the optimal condition for best enzyme activity of a certain enzyme. Instead of looking for the best condition for enzyme activity by doing many similar reactions repeatedly, we can complete this assignment with just one run if we could apply enough conditions.
Date: September 12, 2000
Creator: Ma, L.
Partner: UNT Libraries Government Documents Department
open access

Theoretical Simulations and Ultrafast Pump-probe Spectroscopy Experiments in Pigment-protein Photosynthetic Complexes

Description: Theoretical simulations and ultrafast pump-probe laser spectroscopy experiments were used to study photosynthetic pigment-protein complexes and antennae found in green sulfur bacteria such as Prosthecochloris aestuarii, Chloroflexus aurantiacus, and Chlorobium tepidum. The work focused on understanding structure-function relationships in energy transfer processes in these complexes through experiments and trying to model that data as we tested our theoretical assumptions with calculations. Theo… more
Date: September 12, 2000
Creator: Buck, D. R.
Partner: UNT Libraries Government Documents Department
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