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The refrigeration and cryogenic distribution system for the shortpulse x-ray source (open access)

The refrigeration and cryogenic distribution system for the shortpulse x-ray source

This report describes the essential elements of the cryogenic system. The cryogenic distribution system starts at the level of the linac superconducting RF cavities [1] and moves out through the cryogenic piping to the liquid helium refrigeration plant that will be used to cool the RF cavities and the undulator magnets. For this report, the cryogenic distribution system and cryogenic refrigerator includes the following elements: (1) The piping within the linac cryogenic modules will influence the heat transfer through the super-fluid helium from the outer surface of the TESLA niobium cavity and the liquid to gas interface within the horizontal header pipe where the superfluid helium boils. This piping determines the final design of the linac cryogenic module. (2) The acceptable pressure drops determine the supply and return piping dimensions. (3) The helium distribution system is determined by the need to cool down and warm up the various elements in the light source. (4) The size of the cryogenic plant is determined by the heat loads and the probable margin of error on those heat loads. Since the final heat loads are determined by the acceleration gradient in the cavities, a linac with five cryogenic modules will be compared to …
Date: October 20, 2002
Creator: Green, Michael A. & Corlett, John N.
Object Type: Report
System: The UNT Digital Library
Field and Current Amplification in the SSPX Spheromak (open access)

Field and Current Amplification in the SSPX Spheromak

Results are presented from experiments relating to magnetic field generation and current amplification in the SSPX spheromak. The SSPX spheromak plasma is driven by DC coaxial helicity injection using a 2MJ capacitor bank. Peak toroidal plasma currents of up to 0.7MA and peak edge poloidal fields of 0.3T are produced; lower current discharges can be sustained up to 3.5msec. When edge magnetic fluctuations are reduced below 1% by driving the plasma near threshold, it is possible to produce plasmas with Te > 150eV, <{beta}{sub e}>-4% and core {chi}{sub e} {approx} 30m{sup 2}/s. Helicity balance for these plasmas suggests that sheath dissipation can be significant, pointing to the importance of maximizing the voltage on the coaxial injector. For most operational modes we find a stiff relationship between peak spheromak field and injector current, and little correlation with plasma temperature, which suggests that other processes than ohmic dissipation may limit field amplification. However, slowing spheromak buildup by limiting the initial current pulse increases the ratio of toroidal current to injected current and points to new operating regimes with more favorable current amplification.
Date: October 8, 2002
Creator: Hill, D. N.; Blumer, R. H.; Cohen, B. I.; Hooper, E. B.; McLean, H. S.; Moller, J. et al.
Object Type: Article
System: The UNT Digital Library
Photon Colliders (open access)

Photon Colliders

A photon collider interaction region has the possibility of expanding the physics reach of a future TeV scale electron-positron collider. A survey of ongoing efforts to design the required lasers and optics to create a photon collider is presented in this paper.
Date: October 7, 2002
Creator: Gronberg, J.
Object Type: Article
System: The UNT Digital Library
Alternative Fuel News: Official Publication of the Clean Cities Network and the Alternative Fuels Data Center, Vol. 6, No. 2 (open access)

Alternative Fuel News: Official Publication of the Clean Cities Network and the Alternative Fuels Data Center, Vol. 6, No. 2

Official publication of the Clean Cities Network and the Alternative Fuels Data Center featuring LPG Around the World, AFVs in National Parks, and Federal and State news.
Date: October 1, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies (open access)

The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies

The National Ignition Facility (NIF), currently under construction at the University of California's Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8-Megajoule, 500-Terawatt, 351-nm laser system and a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. NIF is being built by the National Nuclear Security Administration and when completed will be the world's largest laser experimental system, providing a national center to study inertial confinement fusion and the physics of matter at extreme energy densities and pressures. NIF will provide 192 energetic laser beams that will compress small fusion targets to conditions where they will ignite and burn, liberating more energy than is required to initiate the fusion reactions. NIF experiments will allow the study of physical processes at temperatures approaching 100 million K and 100 billion times atmospheric pressure. These conditions exist naturally only in the interior of stars and in nuclear weapons explosions. In the course of designing the world's most energetic laser system, a number of significant technology breakthroughs have been achieved. Research is also underway to develop a shorter pulse capability on NIF for very high power and extreme electromagnetic field research and applications. We discuss here the technology challenges …
Date: October 16, 2002
Creator: Moses, E I & Wuest, C R
Object Type: Article
System: The UNT Digital Library
Global Expression Studies of Yersinia Pestis Pathogenicity (open access)

Global Expression Studies of Yersinia Pestis Pathogenicity

The aim of these studies continues to be the investigation into the molecular mechanisms that underlie the virulence process in Yersinia pestis. In particular, the focus of this work centers on the identification of novel genes and pathways responsible for the pathogenic properties of this organism. In spite of more than four decades of intense investigation in this field, the dilemma as to what makes Y. pestis such a virulent and lethal pathogen remains unanswered. The method being employed makes use microarray technology (DNA chip) that enables the examination of the global activities of the whole complement of genes in this pathogen. Two primary resources available to the investigators (one directly obtained from a separate CBNP-funded project) make these studies possible: (1) Whole genome comparisons of the genes in Y. pestis and its near neighbors with attenuated or non pathogenic characteristics, and (2) the ability to duplicate in vitro, conditions that mimic the infection process of this pathogen. This year we have extended our studies from the original work of characterizing the global transcriptional regulation in Y. pestis triggered during temperature transition from 26 C to 37 C (roughly conditions found in the flea vector and the mammalian host, respectively) …
Date: October 15, 2002
Creator: Garcia, E; Motin, V; Brubaker, R & Fitch, P
Object Type: Report
System: The UNT Digital Library
The LLNL Accelerator Mass Spectrometry System for Biochemical 14C-Measurements (open access)

The LLNL Accelerator Mass Spectrometry System for Biochemical 14C-Measurements

We report on recent improvements made to our 1 MV accelerator mass spectrometry system that is dedicated to {sup 14}C quantification of biochemical samples. Increased vacuum pumping capacity near the high voltage terminal has resulted in a 2-fold reduction of system backgrounds to 0.04 amol {sup 14}C/mg carbon. Carbon ion transmission through the accelerator has also improved a few percent. We have also developed tritium measurement capability on this spectrometer. The {sup 3}H/{sup 1}H isotopic ratio of a milligram-sized processed tap water sample has been measured at 4 {+-} 1 x 10{sup -16} (430 {+-} 110 {micro}Bq/mg H). Measurement throughput for a typical biochemical {sup 3}H sample is estimated to be {approx}10 minutes/sample.
Date: October 31, 2002
Creator: Ognibene, T J; Bench, G; Brown, T A & Vogel, J S
Object Type: Article
System: The UNT Digital Library
Battery Power for Your Residential Solar Electric System: Better Buildings Series Solar Electric Fact Sheet (open access)

Battery Power for Your Residential Solar Electric System: Better Buildings Series Solar Electric Fact Sheet

This consumer fact sheet provides an overview of battery power for residential solar electric systems, including sizing, estimating costs, purchasing, and performing maintenance.
Date: October 1, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Science& Technology Review December 2002 (open access)

Science& Technology Review December 2002

This issue has the following articles: (1) ''Doing It All: Sustaining Our Working Solutions, Rising to New Challenges''; (2) ''Emerging from the Cold War: Stockpile Stewardship and Beyond''--When the Cold War ended, Lawrence Livermore stepped up to a new national challenge--maintaining the safety and reliability of the U.S. nuclear stockpile without underground testing. (3) ''Machines from Interlocking Molecules''--Fundamental chemistry and physics research will enable scientists to control and use individual molecules. (4) ''Laser Zaps Communication Bottleneck''--Using laser communications, the U.S. military will be able to transmit data from advanced remote sensors in real time.
Date: October 28, 2002
Creator: Budil, K S
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Calculated Thermodynamic Functions for Gas Phase Uranium, Neptunium, Plutonium, and Americium Oxides (AnO3), Oxyhydroxides (AnO2(OH)2), Oxychlorides (AnO2Cl2), and Oxyfluorides (AnO2F2) (open access)

Calculated Thermodynamic Functions for Gas Phase Uranium, Neptunium, Plutonium, and Americium Oxides (AnO3), Oxyhydroxides (AnO2(OH)2), Oxychlorides (AnO2Cl2), and Oxyfluorides (AnO2F2)

Based on known and estimated molecular constants, the thermodynamic functions, C{sub p}, S{sup o}, H{sup o}-H{sup o}(298), and -(G{sup o} - H{sup o}(298))/T, have been calculated and tabulated for actinide vapors species of the formulas AnO{sub 3}(g), AnO{sub 2}(OH){sub 2}(g), AnO{sub 2}Cl{sub 2}(g), and AnO{sub 2}F{sub 2}(g) where An = U, Np, Pu, and Am. A method to calculate the thermodynamic functions for the mixed species, AnO{sub 2}ClOH(g), AnO{sub 2}FOH(g), and AnO{sub 2}FCl(g), is also given.
Date: October 31, 2002
Creator: Ebbinghaus, B. B.
Object Type: Report
System: The UNT Digital Library
Recent Advances in Indirect Drive ICF Target Physics (open access)

Recent Advances in Indirect Drive ICF Target Physics

In preparation for ignition on the National Ignition Facility, the Lawrence Livermore National Laboratory's Inertial Confinement Fusion Program, working in collaboration with Los Alamos National Laboratory, Commissariat a lEnergie Atomique (CEA), and Laboratory for Laser Energetics at the University of Rochester, has performed a broad range of experiments on the Nova and Omega lasers to test the fundamentals of the NIF target designs. These studies have refined our understanding of the important target physics, and have led to many of the specifications for the NIF laser and the cryogenic ignition targets. Our recent work has been focused in the areas of hohlraum energetics, symmetry, shock physics, and target design optimization & fabrication.
Date: October 8, 2002
Creator: Hammel, B.; Lindl, J.; Amendt, P. A.; Bernat, G. W.; Collins, G. W.; Glenzer, S. H. et al.
Object Type: Article
System: The UNT Digital Library
Highlighting High Performance: The Solar Energy Research Facility, Golden, Colorado (Revised) (open access)

Highlighting High Performance: The Solar Energy Research Facility, Golden, Colorado (Revised)

The Solar Energy Research Facility at the National Renewable Energy Laboratory includes energy-efficient features, making it a high-performing building.
Date: October 1, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Multiphase Advection and Radiation Diffusion with Material Interfaces on Unstructured Meshes (open access)

Multiphase Advection and Radiation Diffusion with Material Interfaces on Unstructured Meshes

A collection of numerical methods are presented for the advection or remapping of material properties on unstructured and staggered polyhedral meshes in arbitrary Lagrange-Eulerian calculations. The methods include several new procedures to track and capture sharp interface boundaries, and to partition radiation energy into multi-material thermal states. The latter is useful for extending and applying consistently single material radiation diffusion solvers to multi-material problems.
Date: October 3, 2002
Creator: Anninos, P
Object Type: Article
System: The UNT Digital Library
Science& Technology Review October 2002 (open access)

Science& Technology Review October 2002

The October 2002 issue of Science and Technology Review has the following articles: (1) Applied Science Is a Hallmark of This Laboratory--Commentary by Hal Graboske. (2) Sending Up Signals for Genetic Variation--In situ rolling circle amplification promises to advance the detection and treatment of cancer and other diseases. (3) SiMM Is Anything But Simple--Modules of silicon microchannels and microlenses result in the smallest, most powerful, and least expensive laser diode pumps ever. (4) World's Most Powerful Solid-State Laser--A new design allows tremendous scaling up of solid-state laser power. (5) Stepping Up to Extreme Lithography--The next generation of computer chips can now be produced on a commercial scale. (6) Relief for Acute and Chronic Pain--New technology turns an ancient pain management method into a modern medical tool. (7)50th Anniversary Highlight--14 Energy and Environment: Understanding Our World--The Laboratory's energy and environmental research is an important adjunct to its core national security mission.
Date: October 1, 2002
Creator: Budil, K S
Object Type: Report
System: The UNT Digital Library
Universal Interconnection Technology Workshop Proceedings (open access)

Universal Interconnection Technology Workshop Proceedings

The Universal Interconnection Technology (UIT) Workshop - sponsored by the U.S. Department of Energy, Distributed Energy and Electric Reliability (DEER) Program, and Distribution and Interconnection R&D - was held July 25-26, 2002, in Chicago, Ill., to: (1) Examine the need for a modular universal interconnection technology; (2) Identify UIT functional and technical requirements; (3) Assess the feasibility of and potential roadblocks to UIT; (4) Create an action plan for UIT development. These proceedings begin with an overview of the workshop. The body of the proceedings provides a series of industry representative-prepared papers on UIT functions and features, present interconnection technology, approaches to modularization and expandability, and technical issues in UIT development as well as detailed summaries of group discussions. Presentations, a list of participants, a copy of the agenda, and contact information are provided in the appendices of this document.
Date: October 1, 2002
Creator: Sheaffer, P.; Lemar, P.; Honton, E. J.; Kime, E.; Friedman, N. R.; Kroposki, B. et al.
Object Type: Book
System: The UNT Digital Library
A Picosecond 14.7 nm X-Ray Laser for Probing Matter Undergoing Rapid Changes (open access)

A Picosecond 14.7 nm X-Ray Laser for Probing Matter Undergoing Rapid Changes

With laser-driven tabletop x-ray lasers now operating in the efficient saturation regime, the source characteristics of high photon flux, high monochromaticity, picosecond pulse duration, and coherence are well-matched to many applications involving the probing of matter undergoing rapid changes. We give an overview of recent experiments at the Lawrence Livermore National Laboratory (LLNL) Compact Multipulse Terawatt (COMET) laser using the picosecond 14.7 nm x-ray laser as a compact, ultrafast probe for surface analysis and for interferometry of laser-produced plasmas. The plasma density measurements for known laser conditions allow us to reliably and precisely benchmark hydrodynamics codes. In the former case, the x-ray laser ejects photo-electrons, from the valence band or shallow core-levels of the material, and are measured in a time-of-flight analyzer. Therefore, the electronic structure can be studied directly to determine the physical properties of materials undergoing rapid phase changes.
Date: October 7, 2002
Creator: Dunn, J.; Smith, R. F.; Nilsen, J.; Nelson, A. J.; Van Buuren, T. W.; Moon, S. J. et al.
Object Type: Article
System: The UNT Digital Library
National Ignition Facility Configuration Management Plan (open access)

National Ignition Facility Configuration Management Plan

This Configuration Management Plan (CMP) describes the technical and administrative management process for controlling the National Ignition Facility (NIF) Project configuration. The complexity of the NIF Project (i.e., participation by multiple national laboratories and subcontractors involved in the development, fabrication, installation, and testing of NIF hardware and software, as well as construction and testing of Project facilities) requires implementation of the comprehensive configuration management program defined in this plan. A logical schematic illustrating how the plan functions is provided in Figure 1. A summary of the process is provided in Section 4.0, Configuration Change Control. Detailed procedures that make up the overall process are referenced. This CMP is consistent with guidance for managing a project's configuration provided in Department of Energy (DOE) Order 430.1, Guide PMG 10, ''Project Execution and Engineering Management Planning''. Configuration management is a formal discipline comprised of the following four elements: (1) Identification--defines the functional and physical characteristics of a Project and uniquely identifies the defining requirements. This includes selection of components of the end product(s) subject to control and selection of the documents that define the project and components. (2) Change management--provides a systematic method for managing changes to the project and its physical and …
Date: October 1, 2002
Creator: Cabral, S. G. & Moore, T. L.
Object Type: Report
System: The UNT Digital Library
Unstructured Mesh Connectivity in Unstructured Mapping (open access)

Unstructured Mesh Connectivity in Unstructured Mapping

The connectivity interface for UnstructuredMapping has been rewritten to provide a more thorough interface to the mesh. This new design also resembles the TSTT mesh query interface. While data is still stored in array form, indexed by integers, the interface provides iterators through the mesh entities and adjacencies. This document describes the additions to the UnstructuredMapping class as well as the definition and use of the UnstructuredMappingIterator and UnstructuredMappingAdjacencyIterator classes.
Date: October 22, 2002
Creator: Chand, K
Object Type: Text
System: The UNT Digital Library
A Dynamically Adaptive Arbitrary Lagrangian-Eulerian Method for Hydrodynamics (open access)

A Dynamically Adaptive Arbitrary Lagrangian-Eulerian Method for Hydrodynamics

A new method that combines staggered grid Arbitrary Lagrangian-Eulerian (ALE) techniques with structured local adaptive mesh refinement (AMR) has been developed for solution of the Euler equations. The novel components of the combined ALE-AMR method hinge upon the integration of traditional AMR techniques with both staggered grid Lagrangian operators as well as elliptic relaxation operators on moving, deforming mesh hierarchies. Numerical examples demonstrate the utility of the method in performing detailed three-dimensional shock-driven instability calculations.
Date: October 19, 2002
Creator: Anderson, R W; Pember, R B & Elliott, N S
Object Type: Article
System: The UNT Digital Library
PROTEIN QUALITY CONTROL IN BACTERIAL CELLS: INTEGRATED NETWORKS OF CHAPERONES AND ATP-DEPENDENT PROTEASES. (open access)

PROTEIN QUALITY CONTROL IN BACTERIAL CELLS: INTEGRATED NETWORKS OF CHAPERONES AND ATP-DEPENDENT PROTEASES.

It is generally accepted that the information necessary to specify the native, functional, three-dimensional structure of a protein is encoded entirely within its amino acid sequence; however, efficient reversible folding and unfolding is observed only with a subset of small single-domain proteins. Refolding experiments often lead to the formation of kinetically-trapped, misfolded species that aggregate, even in dilute solution. In the cellular environment, the barriers to efficient protein folding and maintenance of native structure are even larger due to the nature of this process. First, nascent polypeptides must fold in an extremely crowded environment where the concentration of macromolecules approaches 300-400 mg/mL and on average, each ribosome is within its own diameter of another ribosome (1-3). These conditions of severe molecular crowding, coupled with high concentrations of nascent polypeptide chains, favor nonspecific aggregation over productive folding (3). Second, folding of newly-translated polypeptides occurs in the context of their vehtorial synthesis process. Amino acids are added to a growing nascent chain at the rate of {approx}5 residues per set, which means that for a 300 residue protein its N-terminus will be exposed to the cytosol {approx}1 min before its C-terminus and be free to begin the folding process. However, because protein …
Date: October 1, 2002
Creator: Flanagan, J. M. & Bewley, M. C.
Object Type: Book
System: The UNT Digital Library
RCRA Groundwater Quality Assessment Report for Single-Shell Tank Waste Management Area TX-TY (January 1998 through December 2001) (open access)

RCRA Groundwater Quality Assessment Report for Single-Shell Tank Waste Management Area TX-TY (January 1998 through December 2001)

This report presents the findings of groundwater monitoring and characterization at WMA TX-TY in the 200 West Area of the Hanford Site.
Date: October 31, 2002
Creator: Horton, Duane G.
Object Type: Report
System: The UNT Digital Library
Fast Ignition: Physics Progress in the US Fusion Energy Program and Prospects for Achieving Ignition. (open access)

Fast Ignition: Physics Progress in the US Fusion Energy Program and Prospects for Achieving Ignition.

Fast ignition (FI) has significant potential advantages for inertial fusion energy and it is therefore being studied as an exploratory concept in the US fusion energy program. FI is based on short pulse isochoric heating of pre-compressed DT by intense beams of laser accelerated MeV electrons or protons. Recent experimental progress in the study of these two heating processes is discussed. The goal is to benchmark new models in order to predict accurately the requirements for full-scale fast ignition. An overview is presented of the design and experimental testing of a cone target implosion concept for fast ignition. Future prospects and conceptual designs for larger scale FI experiments using planned high energy petawatt upgrades of major lasers in the US are outlined. A long-term roadmap for FI is defined.
Date: October 16, 2002
Creator: Key, M. H.; Andersen, C.; Cowan, T.; Fisch, N.; Freeman, R.; Hatchett, S. et al.
Object Type: Article
System: The UNT Digital Library
Pacific Northwest National Laboratory Annual Self-Evaluation Report: 2002 (open access)

Pacific Northwest National Laboratory Annual Self-Evaluation Report: 2002

This report will summarize PNNL's progress toward accomplishment of the critical outcomes, objectives and performance indicators as delineated in the FY 2002 Performance Evaluation and Fee Agreement. In addition, this report will summarize PNNL's analysis of the results of the FY2002 Peer Reviews, the implementation of PNNL's FY2002 Operational Improvement Initiatives, and the resolution of the Key Areas for Improvements.
Date: October 29, 2002
Creator: Cuello, Robert
Object Type: Report
System: The UNT Digital Library
Steam System Opportunity Assessment for the Pulp and Paper, Chemical Manufacturing, and Petroleum Refining Industries: Main Report (open access)

Steam System Opportunity Assessment for the Pulp and Paper, Chemical Manufacturing, and Petroleum Refining Industries: Main Report

This report assesses steam generation and use in the pulp and paper, chemical, and petroleum refining industries, and estimates the potential for energy savings from implementation of steam system performance and efficiency improvements.
Date: October 1, 2002
Creator: unknown
Object Type: Book
System: The UNT Digital Library