Resource Type

Addendum to the 200 West Area Dust Mitigation Strategies: Treatment of the Dust Source Area (open access)

Addendum to the 200 West Area Dust Mitigation Strategies: Treatment of the Dust Source Area

This document describes the source area for the blowing dust encountered in the southwest portion of the 200 West Area. Strategies for short-term stabilization of the entire source area, short-term stabilization of a portion of the source area based on levels of respirable dust, and long-term stabilization of the entire source area are provided. An separate evaluation of aerosolized water as a means of reducing airborne dust is also provided.
Date: May 14, 2001
Creator: Becker, James M. & Sackschewsky, Michael R.
System: The UNT Digital Library
Status Report on high explosive and laser driven Al6061-T651 (open access)

Status Report on high explosive and laser driven Al6061-T651

This report describes work done using isentropic drives based on high-explosives and lasers, along with recovery and ex-situ examination, to characterize material deformation behavior.
Date: November 14, 2003
Creator: Remiington, B; McNaney, J M; Becker, R; Lorenz, K T & Edwards, J E
System: The UNT Digital Library
Homopolar Gun for Pulsed Spheromak Fusion Reactors II (open access)

Homopolar Gun for Pulsed Spheromak Fusion Reactors II

A homopolar gun is discussed that could produce the high currents required for pulsed spheromak fusion reactors even with unit current amplification and open field lines during injection, possible because close coupling between the gun and flux conserver reduces gun losses to acceptable levels. Example parameters are given for a gun compatible with low cost pulsed reactors and for experiments to develop the concept.
Date: June 14, 2004
Creator: Fowler, T.
System: The UNT Digital Library
APDS: Autonomous Pathogen Detection System (open access)

APDS: Autonomous Pathogen Detection System

An early warning system to counter bioterrorism, the Autonomous Pathogen Detection System (APDS) continuously monitors the environment for the presence of biological pathogens (e.g., anthrax) and once detected, it sounds an alarm much like a smoke detector warns of a fire. Long before September 11, 2001, this system was being developed to protect domestic venues and events including performing arts centers, mass transit systems, major sporting and entertainment events, and other high profile situations in which the public is at risk of becoming a target of bioterrorist attacks. Customizing off-the-shelf components and developing new components, a multidisciplinary team developed APDS, a stand-alone system for rapid, continuous monitoring of multiple airborne biological threat agents in the environment. The completely automated APDS samples the air, prepares fluid samples in-line, and performs two orthogonal tests: immunoassay and nucleic acid detection. When compared to competing technologies, APDS is unprecedented in terms of flexibility and system performance.
Date: February 14, 2002
Creator: Langlois, R. G.; Brown, S.; Burris, L.; Colston, B.; Jones, L.; Makarewicz, T. et al.
System: The UNT Digital Library
Upscaling Radionuclide Retardation?Linking the Surface Complexation and Ion Exchange Mechanistic Approach to a Linear Kd Approach (open access)

Upscaling Radionuclide Retardation?Linking the Surface Complexation and Ion Exchange Mechanistic Approach to a Linear Kd Approach

The LLNL near-field hydrologic source term (HST) model is based on a mechanistic approach to radionuclide retardation-that is, a thermodynamic description of chemical processes governing retardation in the near field, such as aqueous speciation, surface complexation, ion exchange, and precipitation The mechanistic approach allows for radionuclide retardation to vary both in space and time as a function of the complex reaction chemistry of the medium. This level of complexity is necessary for near-field HST transport modeling because of the non-linear reaction chemistry expected close to the radiologic source. Large-scale Corrective Action Unit (CAU) models-into which the near-field HST model results feed-require that the complexity of the mechanistic approach be reduced to a more manageable form (e.g. Linear, Langmuir, or Freundlich sorption isotherms, etc). The linear sorption isotherm (or K{sub d}) approach is likely the most simple approach for large-scale CAU models. It may also be the most appropriate since the reaction chemistry away from the near field is expected to be less complex and relatively steady state. However, if the radionuclide retardation approaches in near-field HST and large-scale CAU models are different, they must be proved consistent. In this report, we develop a method to link the near-field HST and …
Date: May 14, 2004
Creator: Zavarin, M; Carle, S & Maxwell, R
System: The UNT Digital Library
Dose-Rate Dependence of High-Dose Health Effects in Humans from Photon Radiation with Application to Radiological Terrorism (open access)

Dose-Rate Dependence of High-Dose Health Effects in Humans from Photon Radiation with Application to Radiological Terrorism

In 1981, as part of a symposium entitled ''The Control of Exposure of the Public to Ionizing Radiation in the Event of Accident or Attack,'' Lushbaugh, H?bner, and Fry published a paper examining ''radiation tolerance'' of various human health endpoints as a function of dose rate. This paper may not have received the notice it warrants. The health endpoints examined by Lushbaugh et al. were the lethal dose that will kill 50% of people within 60 days of exposure without medical care (LD50/60); severe bone marrow damage in healthy men; severe bone marrow damage in leukemia patients; temporary sterility (azoospermia); reduced male fertility; and late effects such as cancer. Their analysis was grounded in extensive clinical experience and anchored to a few selected data points, and based on the 1968 dose-rate dependence theory of J.L. Bateman. The Lushbaugh et al. paper did not give predictive equations for the relationships, although they were implied in the text, and the relationships were presented in a non-intuitive way. This work derives the parameters needed in Bateman's equation for each health endpoint, tabulates the results, and plots them in a more conventional manner on logarithmic scales. The results give a quantitative indication of how …
Date: January 14, 2005
Creator: Strom, Daniel J.
System: The UNT Digital Library
A Generalized Fast Frequency Sweep Algorithm for Coupled Circuit-EM Simulations (open access)

A Generalized Fast Frequency Sweep Algorithm for Coupled Circuit-EM Simulations

An Asymptotic Wave Expansion (AWE) technique is implemented into the EIGER computational electromagnetics code. The AWE fast frequency sweep is formed by separating the components of the integral equations by frequency dependence, then using this information to find a rational function approximation of the results. The standard AWE method is generalized to work for several integral equations, including the EFIE for conductors and the PMCHWT for dielectrics. The method is also expanded to work for two types of coupled circuit-EM problems as well as lumped load circuit elements. After a simple bisecting adaptive sweep algorithm is developed, dramatic speed improvements are seen for several example problems.
Date: December 14, 2004
Creator: Ouyang, G.; Jandhyala, V.; Champagne, N.; Sharpe, R.; Fasenfest, B. J. & Rockway, J. D.
System: The UNT Digital Library
Final report: flight dynamics and impact characteristics of thin flyer plates driven by laser-and electrically-produced plasmas (open access)

Final report: flight dynamics and impact characteristics of thin flyer plates driven by laser-and electrically-produced plasmas

The scope of the project was to conduct experimental and computer modeling studies of the launching, flight characteristics and impacts of thin flyer plates driven by laser ablation under drive conditions where the plate remains a solid and retains its strength. Motivation for the work was to provide the scientific underpinnings for advanced development work on new detonators that will be needed within the next ten years for use in the Laboratory's national security mission. Areas of study were to be coupling of laser energy into the flyer plate during the launch phase, melting and instability growth in the flyer during launch, and an explosive-grain-scale understanding of the shock-to-detonation transition when the flyer plate impacts an explosive target. Knowledge and modeling capability, developed from this study, were to enable us to tailor the launching and acceleration conditions of thin flyer plates to produce an optimum impact for initiating high explosives. Experimental and computational studies of the shock-to-detonation transition were to aid us in developing more efficient initiating explosives for use in future detonators.
Date: February 14, 2001
Creator: Lee, R. S.; Colvin, J.; Frank, A.; Fried, L. & Reaugh, J.
System: The UNT Digital Library
Using Colored Cullet for Making Beautiful Glassware (open access)

Using Colored Cullet for Making Beautiful Glassware

Eight colored glasses from Fire and Light Originals (FLO) and three container cullet glasses were characterized for the viscosity, density, and thermal expansion, glass transition temperature, dilatometer softening temperature, color chromaticity, Fe(II)/Fe(total) redox ratio, and chemical composition. The results of the characterization were used to evaluate the options for the glass formulation development of colored glasses aimed at increasing the use of recycled container glass cullet. Out of several options considered, the possibility of using clear cullet for FLO’s Citrus colored glass was selected and investigated in this study. It was shown that it is possible to use clear cullet to produce Citrus glass at the cullet oxide ratio of 90 mass% and the final color can be adjusted by controlling the nitrate level and alkali concentrations. From the present study, recommendations for further development efforts are provided to increase the container cullet usage or to replace partially or entirely the clear cullet by the amber cullet.
Date: March 14, 2003
Creator: Kim, Dong-Sang & Matyas, Josef
System: The UNT Digital Library
KCAT Performance Summary - Update, Rev 1 (open access)

KCAT Performance Summary - Update, Rev 1

High Energy Density Physics (HEDP) experiments play an important role in corroborating the improved physics codes that underlie LLNL's Stockpile Stewardship mission. Conducting these experiments, whether on the National Ignition Facility (NIF) or another national facility such as Omega, will require not only improvement in the diagnostics for measuring the experiment, but also detailed knowledge of the as-built target components and assemblies themselves. To assist in this effort, a defined set of well-known reference standards designed to represent a range of HEDP targets have been built and are being used to quantify the performance of different characterization techniques. Without the critical step of using reference standards for qualifying characterization tools there can be no verification of either commercial or internally-developed characterization techniques and thus an uncertainty in the input to the physics code models would exist.
Date: September 14, 2004
Creator: Waters, A.; Martz, H.; Logan, C.; Gross, J. & Chinn, D.
System: The UNT Digital Library
Ultrasonic NDE of Multilayered Structures (open access)

Ultrasonic NDE of Multilayered Structures

This project developed ultrasonic nondestructive evaluation techniques based on guided and bulk waves in multilayered structures using arrays. First, a guided wave technique was developed by preferentially exciting dominant modes with energy in the layer of interest via an ultrasonic array. Second, a bulk wave technique uses Fermat's principle of least time as well as wave-based properties to reconstruct array data and image the multilayered structure. The guided wave technique enables the inspection of inaccessible areas of a multilayered structure without disassembling it. Guided waves propagate using the multilayer as a waveguide into the inaccessible areas from an accessible position. Inspecting multi-layered structures with a guided wave relies on exciting modes with sufficient energy in the layer of interest. Multilayered structures are modeled to determine the possible modes and their distribution of energy across the thickness. Suitable modes were determined and excited by designing arrays with the proper element spacing and frequency. Bulk wave imaging algorithms were developed to overcome the difficulties of multiple reflections and refractions at interfaces. Reconstruction algorithms were developed to detect and localize flaws. A bent-ray algorithm incorporates Fermat's principle to correct time delays in the ultrasonic data that result from the difference in wave speeds …
Date: February 14, 2005
Creator: Quarry, M. J.; Fisher, K. A. & Lehman, S. K.
System: The UNT Digital Library
Advancing Climate and Carbon Simulation (open access)

Advancing Climate and Carbon Simulation

We use a recently developed integrated climate/carbon model to perform breakthrough studies of the climate. Two major studies are carried out--namely the effects of CO{sub 2}-fertilized vegetation on global climate and carbon dynamics, and the effect of climate sensitivity on carbon cycle feedback. We have also begun development of a next-generation climate/carbon modeling capability.
Date: December 14, 2004
Creator: Thompson, S.
System: The UNT Digital Library