805 MHz and 201 MHz RF cavity development for MUCOOL (open access)

805 MHz and 201 MHz RF cavity development for MUCOOL

A muon cooling channel calls for very high acceleratinggradient RF structures to restore the energy lost by muons in theabsorbers. The RF structures have to be operated in a strong magneticfield and thus the use of superconducting RF cavities is excluded. Toachieve a high shunt impedance while maintaining a large enough apertureto accommodate a large transverse emittance muon beam, the cavity designadopted is a pillbox-like geometry with thin Be foils to terminate theelectromagnetic field at the cavity iris. The possibility of using gridsof thin-walled metallic tubes for the termination is also being explored.Many of the RF-related issues for muon cooling channels are being studiedboth theoretically and experimentally using an 805 MHz cavity that has apillbox-like geometry with thin Be windows to terminate the cavityaperture. The design and performance of this cavity are reported here.High-power RF tests of the 805 MHz cavity are in progress at Lab G inFermilab. The cavity has exceeded its design gradient of 30 MV/m,reaching 34 MV/m without external magnetic field. No surface damage wasobserved at this gradient. The cavity is currently under conditioning atLab G with an external magnetic field of 2.5 T. We also present here a201 MHz cavity design for muoncooling channels. The proposed …
Date: October 10, 2002
Creator: DLi@lbl.gov
Object Type: Article
System: The UNT Digital Library
Accelerated Geothermal Resource Development in the Great Basin Through Enhanced Public Awareness and Outreach to Shareholders. (open access)

Accelerated Geothermal Resource Development in the Great Basin Through Enhanced Public Awareness and Outreach to Shareholders.

The Great Basin Center for Geothermal Energy conducted work encompassing two main tasks. We (1) produced a web-based, stakeholder geothermal information system for Nevada geothermal data relevant to assessing and developing geothermal resources, and (2) we held informational stakeholder workshops (both as part of GeoPowering the West Initiative). The objective of this grant was to conduct workshops and fund database and web development activities. This grant funds salaries for web and database developers and part of the administrative assistant who helps to coordinate and organize workshops, and maintain selected databases.
Date: April 10, 2002
Creator: Taranik, James V.; Oppliger, Gary & Sawatsky, Don
Object Type: Report
System: The UNT Digital Library
Advanced Chemistry Basins Model (open access)

Advanced Chemistry Basins Model

The DOE-funded Advanced Chemistry Basin model project is intended to develop a public domain, user-friendly basin modeling software under PC or low end workstation environment that predicts hydrocarbon generation, expulsion, migration and chemistry. The main features of the software are that it will: (1) afford users the most flexible way to choose or enter kinetic parameters for different maturity indicators; (2) afford users the most flexible way to choose or enter compositional kinetic parameters to predict hydrocarbon composition (e.g., gas/oil ratio (GOR), wax content, API gravity, etc.) at different kerogen maturities; (3) calculate the chemistry, fluxes and physical properties of all hydrocarbon phases (gas, liquid and solid) along the primary and secondary migration pathways of the basin and predict the location and intensity of phase fractionation, mixing, gas washing, etc.; and (4) predict the location and intensity of de-asphaltene processes. The project has be operative for 36 months, and is on schedule for a successful completion at the end of FY 2003.
Date: November 10, 2002
Creator: Goddard, William; Blanco, Mario; Cathles, Lawrence; Manhardt, Paul; Meulbroek, Peter & Tang, Yongchun
Object Type: Report
System: The UNT Digital Library
AISI/DOE Technology Roadmap Program: Improved Surface Quality of Exposed Automotive Sheet Steels (open access)

AISI/DOE Technology Roadmap Program: Improved Surface Quality of Exposed Automotive Sheet Steels

Surface quality of sheet steels is an important economic and technical issue for applications such as critical automotive surfaces. This project was therefore initiated to develop a more quantitative methodology for measuring surface imperfections, and to assess their response to forming and painting, particularly with respect to their visibility or invisibility after painting. The objectives were met, and included evaluation of a variety of imperfections present on commercial sheet surfaces or simulated using methods developed in the laboratory. The results are expected to have significant implications with respect to the methodology for assessing surface imperfections, development of quantitative criteria for surface inspection, and understanding and improving key painting process characteristics that influence the perceived quality of sheet steel surfaces.
Date: October 10, 2002
Creator: Speer, John G.; Matlock, David K.; Meyers, Noel & Choi, Young-Min
Object Type: Report
System: The UNT Digital Library
Alkaline Leaching of Key, Non-Radioactive Components from Simulants and Hanford Tank Sludge 241-S-110: Results of FY01 Studies (open access)

Alkaline Leaching of Key, Non-Radioactive Components from Simulants and Hanford Tank Sludge 241-S-110: Results of FY01 Studies

This study addressed three aspects in selected alkaline leaching: first, the use of oxidants persulfate, permanganate, and ferrate as selective chromium-leaching agents from washed Hanford Tank S-110 solids under varying conditions of hydroxide concentration, temperature, and time was investigated. Second, the selective dissolution of solids containing mercury(II) oxide under alkaline conditions was examined. Various compounds were studied for their effectiveness in dissolving mercury under varying conditions of time, temperature, and hydroxide concentration in the leachate. Three compounds were studied: cysteine, iodide, and diethyldithiophosphoric acid (DEDTPA). Finally, the possibility of whether an oxidant bound to an anion-exchange resin can be used to effectively oxidize chromium(III) in alkaline solutions was addressed. The experimental results remain ambiguous to date; further work is required to reach any definitive conclusions as to the effectiveness of this approach.
Date: September 10, 2002
Creator: Rapko, Brian M.; Vienna, John D.; Sinkov, Serguei I.; Kim, Jinseong & Cisar, Alan J.
Object Type: Report
System: The UNT Digital Library
Amplitude and TIme Measurement ASIC With Analog Derandomization (open access)

Amplitude and TIme Measurement ASIC With Analog Derandomization

We describe a new ASIC for accurate and efficient processing of high-rate pulse signals from highly segmented detectors. In contrast to conventional approaches, this circuit affords a dramatic reduction in data volume through the use of analog techniques (precision peak detectors and time-to-amplitude converters) together with fast arbitration and sequencing logic to concentrate the data before digitization. In operation the circuit functions like a data-driven analog first-in, first-out (FIFO) memory between the preamplifiers and the ADC. Peak amplitudes of pulses arriving at any one of the 32 inputs are sampled, stored, and queued for readout and digitization through a single output port. Hit timing, pulse risetime, and channel address are also available at the output. Prototype chips have been fabricated in 0.35 micron CMOS and tested. First results indicate proper functionality for pulses down to 30 ns peaking time and input rates up to 1.6 MHz/channel. Amplitude accuracy of the peak detect and hold circuit is 0.3% (absolute). TAC accuracy is within 0.3% of full scale. Power consumption is less than 2 mW/channel. Compared with conventional techniques such as track-and-hold and analog memory, this new ASIC will enable efficient pulse height measurement at 20 to 300 times higher rates.
Date: November 10, 2002
Creator: O'Connor, P.; De Geronimo, G. & Kandasamy, A.
Object Type: Article
System: The UNT Digital Library
Analysis of Disposal of Lead in the E-Area Low-Level Waste Facility (open access)

Analysis of Disposal of Lead in the E-Area Low-Level Waste Facility

Savannah River Site has received approval from SCDHEC for disposal of radioactively contaminated equipment with lead shielding or counterweights. The objective of this analysis was to document the technical basis for the administrative limit of 100,000 pounds approved by SCDHEC under alternative disposal strategies.
Date: May 10, 2002
Creator: Wilhite, E.L.
Object Type: Report
System: The UNT Digital Library
Application of PCT to the EBR II ceramic waste form. (open access)

Application of PCT to the EBR II ceramic waste form.

We are evaluating the use of the Product Consistency Test (PCT) developed to monitor the consistency of borosilicate glass waste forms for application to the multiphase ceramic waste form (CWF) that will be used to immobilize waste salts generated during the electrometallurgical conditioning of spent sodium-bonded nuclear fuel from the Experimental Breeder Reactor No. 2 (EBR II). The CWF is a multiphase waste form comprised of about 70% sodalite, 25% borosilicate glass binder, and small amounts of halite and oxide inclusions. It must be qualified for disposal as a non-standard high-level waste (HLW) form. One of the requirements in the DOE Waste Acceptance System Requirements Document (WASRD) for HLW waste forms is that the consistency of the waste forms be monitored.[1] Use of the PCT is being considered for the CWF because of the similarities of the dissolution behaviors of both the sodalite and glass binder phases in the CWF to borosilicate HLW glasses. This paper provides (1) a summary of the approach taken in selecting a consistency test for CWF production and (2) results of tests conducted to measure the precision and sensitivity of the PCT conducted with simulated CWF.
Date: January 10, 2002
Creator: Ebert, W. L.; Lewis, M. A. & Johnson, S. G.
Object Type: Article
System: The UNT Digital Library
An assessment of the impact of decommissioning the Cray SV1 systems at NERSC (open access)

An assessment of the impact of decommissioning the Cray SV1 systems at NERSC

None
Date: June 10, 2002
Creator: Carter, Jonathan T.
Object Type: Report
System: The UNT Digital Library
Asymmetric perfectly matched layer for the absorption of waves (open access)

Asymmetric perfectly matched layer for the absorption of waves

The Perfectly Matched Layer (PML) has become a standard for comparison in the techniques that have been developed to close the system of Maxwell equations (more generally wave equations) when simulating an open system. The original Berenger PML formulation relies on a split version of Maxwell equations with numerical electric and magnetic conductivities. They present here an extension of this formulation which introduces counterparts of the electric and magnetic conductivities affecting the term which is spatially differentiated in the equations. they phase velocity along each direction is also multiplied by an additional coefficient. They show that, under certain constraints on the additional numerical coefficients, this ''medium'' does not generate any reflection at any angle and any frequency and is then a Perfectly Matched Layer. Technically it is a super-set of Berenger's PML to which it reduces for a specific set of parameters and like it, it is anisotropic. However, unlike the PML, it introduces some asymmetry in the absorption rate and is therefore labeled an APML for Asymmetric Perfectly Matched Layer. They present here the numerical considerations that have led them to introduce such a medium as well as its theory. Several finite-different numerical implementations are derived (in one, two …
Date: February 10, 2002
Creator: Vay, Jean-Luc
Object Type: Article
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Facilities Newsletter, December 2001. (open access)

Atmospheric Radiation Measurement Program Facilities Newsletter, December 2001.

Monthly newsletter discussing news and activities related to the Atmospheric Radiation Measurement Program, articles about weather and atmospheric phenomena, and other related topics.
Date: January 10, 2002
Creator: Atmospheric Radiation Measurement Program (U.S.)
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Atmospheric Release Assessment Program (ARAP) Science and Technology Base Development (open access)

Atmospheric Release Assessment Program (ARAP) Science and Technology Base Development

ARAP s integrated suite of research, development, and operational programs is focused on the creation of capabilities for predicting the consequences of atmospheric releases of hazardous materials. The foundation of ARAP lies in its science and technology base in multi-scale meteorological and dispersion modeling, field experiments, and software systems (databases, real-time data acquisition software, and remote-access tools). Scientific and technological advancements are integrated into DOENNSA s operational National Atmospheric Release Advisory Center (NARAC) at LLNL to support emergency response, pre-event planning, preparedness, and consequence analysis. Some recent ARAP development highlights are described below.
Date: May 10, 2002
Creator: Ermak, D L; Sugiyama, G & Nasstrom, J S
Object Type: Report
System: The UNT Digital Library
Authorization policy in a PKI environment (open access)

Authorization policy in a PKI environment

The major emphasis of Public Key Infrastructure has been to provide a cryptographically secure means of authenticating identities. While there are a number of proposed standards for authorization structures and protocols based on X.509 or other key-based identities, none have been widely adopted. As part of an effort to use X.509 identities to provide authorization in highly distributed environments, we have developed and deployed an authorization service based on X.509 identified users and access policy contained in certificates signed by X.509 identified stakeholders. The major goal of this system, called Akenti, is to produce a usable authorization system for an environment consisting of distributed resources used by geographically and administratively distributed users.
Date: April 10, 2002
Creator: Thompson, Mary R.; Mudumbai, Srilekha S.; Essiari, Abdelilah & Chin, Willie
Object Type: Article
System: The UNT Digital Library
Beam rounders for circular colliders (open access)

Beam rounders for circular colliders

By means of linear optics, an arbitrary uncoupled beam can be locally transformed into a round (rotation-invariant) state and then back. This provides an efficient way to round beams in the interaction region of circular colliders.
Date: December 10, 2002
Creator: Nagaitsev, A. Burov and S.
Object Type: Article
System: The UNT Digital Library
CO2 Capture Project: An Integrated, Collaborative Technology Development Project For CO2 Separation, Capture And Geologic Sequestration (open access)

CO2 Capture Project: An Integrated, Collaborative Technology Development Project For CO2 Separation, Capture And Geologic Sequestration

This report (which forms part of the requirements of the Statement of Work Task 0, subtask 0.4) records progress towards defining a detailed Work Plan for the CCP 30 days after contract initiation. It describes the studies planned, workscope development and technology provider bid evaluation status at that time. Business sensitive information is provided separately in Appendix 1. Contract negotiations are on hold pending award of patent waiver status to the CCP.
Date: January 10, 2002
Creator: Kerr, Helen
Object Type: Report
System: The UNT Digital Library
CO2 Capture Project: An Integrated, Collaborative Technology Development Project For CO2 Separation, Capture And Geologic Sequestration (open access)

CO2 Capture Project: An Integrated, Collaborative Technology Development Project For CO2 Separation, Capture And Geologic Sequestration

None
Date: July 10, 2002
Creator: Kerr, Helen
Object Type: Report
System: The UNT Digital Library
Coincidence Prompt Gamma-Ray Neutron Activation Analysis (open access)

Coincidence Prompt Gamma-Ray Neutron Activation Analysis

The normal prompt gamma-ray neutron activation analysis for either bulk or small beam samples inherently has a small signal-to-noise (S/N) ratio due primarily to the neutron source being present while the sample signal is being obtained. Coincidence counting offers the possibility of greatly reducing or eliminating the noise generated by the neutron source. The present report presents our results to date on implementing the coincidence counting PGNAA approach. We conclude that coincidence PGNAA yields: (1) a larger signal-to-noise (S/N) ratio, (2) more information (and therefore better accuracy) from essentially the same experiment when sophisticated coincidence electronics are used that can yield singles and coincidences simultaneously, and (3) a reduced (one or two orders of magnitude) signal from essentially the same experiment. In future work we will concentrate on: (1) modifying the existing CEARPGS Monte Carlo code to incorporate coincidence counting, (2) obtaining coincidence schemes for 18 or 20 of the common elements in coal and cement, and (3) optimizing the design of a PGNAA coincidence system for the bulk analysis of coal.
Date: November 10, 2002
Creator: Gardner, R. P.; Mayo, C. W.; Metwally, W. A.; Zhang, W.; Guo, W. & Shehata, A.
Object Type: Report
System: The UNT Digital Library
Constant Load SCC Initiation Response of Alloy 22 (UNS N06022), Titanium Grade 7 and Stainless Steels at 105C (open access)

Constant Load SCC Initiation Response of Alloy 22 (UNS N06022), Titanium Grade 7 and Stainless Steels at 105C

This paper provides an update on research addressing the effects of material condition and applied stress on stress corrosion cracking (SCC) in waste package and drip shield materials for the Yucca Mountain Project. Time-to-failure experiments are being performed on smooth bar tensile specimens in a hot, concentrated, mixed-salt solution chosen to simulate concentrated Yucca Mountain water. The effects of applied stress, welding, surface finish, shot peening, cold work, crevicing, and aging treatment are being investigated for Alloy 22 (UNS N06022). Aging treatments were designed to produce topologically close-packed phases (TCP) and long-range ordering (LRO) and are under investigation as worse-case scenarios for possible microstructures in Alloy 22 (UNS N06022). Titanium Grade 7 and 3 16NG stainless steel are included in the matrix, as they are identified for drip shield and waste package components, respectively. Sensitized 304SS specimens are included in the test matrix to provide benchmark data. This research complements high-resolution crack-growth-rate experiments currently being performed in a parallel research project.
Date: October 10, 2002
Creator: Young, L. M.; Catlin, G. M.; Andresen, P. L. & Gordon, G. M.
Object Type: Report
System: The UNT Digital Library
CONTROL SYSTEM ANALYSIS FOR THE PERTURBED LINEAR ACCELERATOR RF SYSTEM (open access)

CONTROL SYSTEM ANALYSIS FOR THE PERTURBED LINEAR ACCELERATOR RF SYSTEM

This paper addresses the modeling problem of the linear accelerator RF system in SNS. Klystrons are modeled as linear parameter varying systems. The effect of the high voltage power supply ripple on the klystron output voltage and the output phase is modeled as an additive disturbance. The cavity is modeled as a linear system and the beam current is modeled as the exogenous disturbance. The output uncertainty of the low level RF system which results from the uncertainties in the RF components and cabling is modeled as multiplicative uncertainty. Also, the feedback loop uncertainty and digital signal processing signal conditioning subsystem uncertainties are lumped together and are modeled as multiplicative uncertainty. Finally, the time delays in the loop are modeled as a lumped time delay. For the perturbed open loop system, the closed loop system performance, and stability are analyzed with the PI feedback controller.
Date: April 10, 2002
Creator: KWON, SUNG-IL & REGAN, AMY H.
Object Type: Report
System: The UNT Digital Library
Design Analysis for a Scaled Erosion Test (open access)

Design Analysis for a Scaled Erosion Test

In support of a slurry wear evaluation in the pretreatment filtration and evaporation systems of RPP-WTP, Engineering Modeling and Simulation Group (EMSG) has developed the computational models to help guide component design and scaling decisions and to assist in the full-scale analyses. This report deals with the filtration system. In this project, computational fluid dynamics (CFD) methods were applied to ensure that the test facility design would capture the erosion phenomena expected in the full-scale cross-flow ultrafiltration facility. The literature survey was initially performed to identify the principal mechanisms of erosion for a solids laden fluid.
Date: April 10, 2002
Creator: Lee, Si Young
Object Type: Report
System: The UNT Digital Library
Design of 2.4 GHz CMOS Direct Conversion LNA and Mixer Combination for Wirless Data-Link Transceiver (open access)

Design of 2.4 GHz CMOS Direct Conversion LNA and Mixer Combination for Wirless Data-Link Transceiver

Three LNA and mixer combinations in 0.6{micro}m and 0.4{micro}m standard CMOS processes for direct-conversion receiver of 2.4GHz ISM band short-range wireless data-link applications are described in this paper. Taking low power dissipation as first consideration, these designs, employing differential common-source LNA and double balanced mixer architectures, achieve total conversion gain as high as 42.4dB, DSB noise figure as low as 9.5dB, output-referred IP3 as high as of 21.3dBm at about 4mA DC current consumption. This proves it is possible to apply standard CMOS process to implement receiver front-end with low power dissipation for this kind of application, but gain changeable LNA is needed to combat the dominant flicker noise of the mixer in order to achieve acceptable sensitivity and dynamic range at the same time.
Date: April 10, 2002
Creator: Zhao, Desong & O'Connor, Paul
Object Type: Report
System: The UNT Digital Library
Determination of Importance Evaluation for Exploratory Studies Facility (ESF) Subsurface Testing Activities (open access)

Determination of Importance Evaluation for Exploratory Studies Facility (ESF) Subsurface Testing Activities

None
Date: May 10, 2002
Creator: Goodin, S.
Object Type: Report
System: The UNT Digital Library
Developing High Brightness and High Current Beams for HIF Injectors (open access)

Developing High Brightness and High Current Beams for HIF Injectors

The US Heavy Ion Fusion Virtual National Laboratory is continuing research into ion sources and injectors that simultaneously provide high current (0.5-1.0 Amps) and high brightness (normalized emittance better than 1.0 {pi}-mm-mr). The central issue of focus is whether to carry on the traditional approach of large surface ionization sources or to adopt a multi-aperture approach that transports many smaller ''beamlets'' separately at low energies before allowing them to merge. For the large surface source, the recent commissioning of the 2-MeV injector for the High Current experiment has increased our understanding of the beam quality limitations for these sources. We have also improved our techniques for fabricating large diameter aluminosilicate sources to improve lifetime and emission uniformity. For the multi-aperture approach we are continuing to study the feasibility of small surface sources and a RF induced plasma source in preparation for beamlet merging experiments, while continuing to run computer simulations for better understanding of this alternate concept. Experiments into both architectures will be performed on a newly commissioned ion source test stand at LLNL called the STS-500. This stand test provides a platform for testing a variety of ion sources and accelerating structures with 500 kV, 17-microsecond pulses. Recent progress …
Date: May 10, 2002
Creator: Ahle, L & Kwan, J W
Object Type: Article
System: The UNT Digital Library
Development of Low Cost Carbonaceous Materials for Anodes in Lithium-Ion Batteries for Electric and Hybrid Electric Vehicles (open access)

Development of Low Cost Carbonaceous Materials for Anodes in Lithium-Ion Batteries for Electric and Hybrid Electric Vehicles

Final report on the US DOE CARAT program describes innovative R & D conducted by Superior Graphite Co., Chicago, IL, USA in cooperation with researchers from the Illinois Institute of Technology, and defines the proper type of carbon and a cost effective method for its production, as well as establishes a US based manufacturer for the application of anodes of the Lithium-Ion, Lithium polymer batteries of the Hybrid Electric and Pure Electric Vehicles. The three materials each representing a separate class of graphitic carbon, have been developed and released for field trials. They include natural purified flake graphite, purified vein graphite and a graphitized synthetic carbon. Screening of the available on the market materials, which will help fully utilize the graphite, has been carried out.
Date: December 10, 2002
Creator: Barsukov, Igor V.
Object Type: Report
System: The UNT Digital Library