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2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector (open access)

2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector

There are five 2.5 MHz ferrite cavities (h = 28) in the Main Injector with an R/Q of 500 that are presently used for coalescing for the Tevatron. For use with the Fermilab Recycler, feedforward (FF) beam loading compensation (BLC) is required on these cavities because they will be required to operate at a net of 2 kV. Under current Recycler beam conditions, the beam-induced voltage is of this order. Recently a system using a digital bucket delay module operating at 53 MHz (h = 588) was used to produce a one-turn-delay feedforward signal. This signal was then combined with the low level RF signal to the 2.5 MHz cavities to cancel the beam induced voltage. During current operation they have shown consistently to operate with over a 20 dB reduction in beam loading.
Date: May 19, 2003
Creator: Dey, Joseph E.; Kourbanis, Ioanis & Steimel, James
Object Type: Article
System: The UNT Digital Library
3,2-HOPO Complexes of Near-Infra-Red (NIR) Emitting Lanthanides: Sensitization of Ho(III) and Pr(III) in Aqueous Solution (open access)

3,2-HOPO Complexes of Near-Infra-Red (NIR) Emitting Lanthanides: Sensitization of Ho(III) and Pr(III) in Aqueous Solution

There is a growing interest in Near Infra-Red (NIR) emission originating from organic complexes of Ln{sup III} cations. As a major impetus, biological tissues are considerably more transparent at these low energy wavelengths when compared to visible radiation, which facilitates deeper penetration of incident and emitted light. Furthermore, the long luminescence lifetimes of Ln{sup III} complexes (eg. Yb{sup III}, {tau}{sub rad} {approx} 1 ms) when compared to typical organic molecules can be utilized to vastly improve signal to noise ratios by employing time-gating techniques. While the improved quantum yield of Yb{sub III} complexes when compared to other NIR emitters favors their use for bioimaging applications, there has also been significant interest in the sensitized emission from other 4f metals such as Ln = Nd, Ho, Pr and Er which have well recognized applications as solid state laser materials (eg. Nd {approx} 1.06 {micro}m, Ho {approx} 2.09 {micro}m), and in telecommunications (eg. Er {approx} 1.54 {micro}m) where they can be used for amplification of optical signals. As a result of their weak (Laporte forbidden) f-f absorptions, the direct excitation of Ln{sup III} cations is inefficient, and sensitization of the metal emission is more effectively achieved using the so-called antenna effect. We …
Date: May 19, 2008
Creator: Moore, Evan G.; Szigethy, Geza; Xu, Jide; Palsson, Lars-Olof; Beeby, Andrew & Raymond, Kenneth N.
Object Type: Article
System: The UNT Digital Library
53 MHZ Feedforward beam loading compensation in the Fermilab main injector (open access)

53 MHZ Feedforward beam loading compensation in the Fermilab main injector

53 MHz feedforward beam loading compensation is crucial to all operations of the Main Injector. Recently a system using a fundamental frequency down converter mixer, a digital bucket delay module and a fundamental frequency up converter mixer were used to produce a one-turn-delay feedforward signal. This signal was then combined with the low level RF signal to the cavities to cancel the transient beam induced voltage. During operation they have shown consistently over 20 dB reduction in side-band voltage around the fundamental frequency during Proton coalescing and over 14 dB in multi-batch antiproton coalescing.
Date: May 19, 2003
Creator: al., Joseph E Dey et
Object Type: Article
System: The UNT Digital Library
100 Area excavation treatability study data validation report (open access)

100 Area excavation treatability study data validation report

This report presents the results of sampling and chemical analyses at Hanford Reservation. The samples were analyzed by Thermo-Analytic Laboratories and Roy F. Weston Laboratories using US Environmental Protection Agency CLP protocols. Sample analyses included: volatile organics; semivolatile organics; inorganics; and general chemical parameters. The data from the chemical analyses were reviewed and validated to verify that reported sample results were of sufficient quality to support decisions regarding remedial actions performed at this site.
Date: May 19, 1994
Creator: Frain, J. M.
Object Type: Report
System: The UNT Digital Library
242-A Control System device logic software documentation. Revision 2 (open access)

242-A Control System device logic software documentation. Revision 2

A Distributive Process Control system was purchased by Project B-534. This computer-based control system, called the Monitor and Control System (MCS), was installed in the 242-A Evaporator located in the 200 East Area. The purpose of the MCS is to monitor and control the Evaporator and Monitor a number of alarms and other signals from various Tank Farm facilities. Applications software for the MCS was developed by the Waste Treatment System Engineering Group of Westinghouse. This document describes the Device Logic for this system.
Date: May 19, 1995
Creator: Berger, J. F.
Object Type: Report
System: The UNT Digital Library
2006 Pantex Plant Annual Illness and Injury Surveillance Report (open access)

2006 Pantex Plant Annual Illness and Injury Surveillance Report

The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of illness and injury surveillance activities that provide an early warning system to detect health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: May 19, 2008
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
Acceptance test procedure for the 105-KW isolation barrier leak rate (open access)

Acceptance test procedure for the 105-KW isolation barrier leak rate

This acceptance test procedure shall be used to: First establish a basin water loss rate prior to installation of the two isolation barriers between the main basin and the discharge chute in K-Basin West. Second, perform an acceptance test to verify an acceptable leakage rate through the barrier seals. This Acceptance Test Procedure (ATP) has been prepared in accordance with CM-6-1 EP 4.2, Standard Engineering Practices.
Date: May 19, 1995
Creator: McCracken, K. J.
Object Type: Report
System: The UNT Digital Library
Activation and micropore structure determination of carbon-fiber composite molecular sieves. Topical report, 30 March 1994--14 April 1995 (open access)

Activation and micropore structure determination of carbon-fiber composite molecular sieves. Topical report, 30 March 1994--14 April 1995

Progress in developing novel, rigid, monolithic adsorbent carbon fiber composites is described. Carbon fiber composites are activated using steam or CO{sub 2}, in order to produce uniform activation through the material and to control the pore structure and adsorptive properties. There is an overall shrinkage during activation, which is directly correlated with burnoff; burnoff above 40% results in fracture. Burnoffs higher than 10% does not produce any benefit for separation of CH{sub 4}-CO{sub 2} mixtures. Five samples of CFCMS have been prepared for testing as molecular sieves; all have relatively narrow pore size distributions with average pore diameters around 6A.
Date: May 19, 1995
Creator: Jagtoyen, M.; Derbyshire, F.; Kimber, G. & Fei, You Qing
Object Type: Report
System: The UNT Digital Library
Advanced, soluble hydroliquefaction and hydrotreating catalysts. Quarterly reports No. 10 and 11, January 1, 1993--May 30, 1993 (open access)

Advanced, soluble hydroliquefaction and hydrotreating catalysts. Quarterly reports No. 10 and 11, January 1, 1993--May 30, 1993

The purpose of the present program is to develop soluble analogs of surface confined catalysts that can be impregnated directly into the coal structure at low temperatures. This approach should avoid problems related to surface area dependence, a two phase (surface-liquid) reaction system and, mass transport limitations. Heteropolyanions (HPAs) offer the opportunity to develop soluble forms of surface confined catalysts. HPAs, are inexpensive, well-characterized, water soluble metal oxide clusters, e.g. [EM {sub 12}O{sub 40}]{sup 14{minus}} where E = Si or P and M = Mo or W. They are easily modified to contain other transition metals such as Co, Ni or Ru and, can be made soluble in organic solvents. The protic forms exhibit extremely high acidities pK{sub a} {approx} 0--2. In addition, selectively modified RPAs can function as low temperature hydrogenation catalysts that exhibit microporosity HPAs are multifunctional catalysts that could be used to promote both hydroliquefaction and hydrotreating. In theory, these functions could be employed sequentially or simultaneously and could permit exceptional control of liquefaction reactions and reaction conditions. Thus, the current research program involves efforts to evaluate HPAs as soluble liquefaction and hydrotreating catalysts, with the goal of developing soluble analogs of surface confined catalysts. Alternately, if …
Date: May 19, 1993
Creator: Laine, R. M. & Stoebe, T.
Object Type: Report
System: The UNT Digital Library
Advances in Nb3Sn Performance (open access)

Advances in Nb3Sn Performance

Nb{sub 3}Sn wires with non-Cu critical current densities (J{sub c}) that surpass 3 kAmm{sup -2} at 12 T and 4.2 K are commercially available in piece lengths longer than 10 km. Accelerator-type magnets that utilize these conductors have achieved record magnetic fields. This article summarizes key developments in the last decade that have led to these significant improvements in the performance of Nb{sub 3}Sn wires.
Date: May 19, 2008
Creator: Godeke, Arno
Object Type: Article
System: The UNT Digital Library
Analysis and stabilization of Lawrence Berkeley Laboratory`s multiphase mixed waste (open access)

Analysis and stabilization of Lawrence Berkeley Laboratory`s multiphase mixed waste

Five drums of mixed waste were accepted from LBL during FY 1994; they contain inorganic acids and compounds, as well as organic reagents and radioactive materials. This document defines the work plan for stabilization and characterization of the waste in three of these 5 drums.
Date: May 19, 1995
Creator: Crawford, B. A.
Object Type: Report
System: The UNT Digital Library
Analysis of the stored energy distribution in D-reactor (open access)

Analysis of the stored energy distribution in D-reactor

The purpose of this document is to characterize, as completely as possible, the stored energy distribution in D Reactor as of March 1958, the date of the last stored energy survey and to estimate the temperature rises which can be expected to occur during a stored energy release. D Reactor was chosen for this study only because it represents one of the oldest operating Hanford reactors and not because of any circumstances peculiar to this reactor. 14 refs., 13 figs.
Date: May 19, 1961
Creator: Morgan, W. C.
Object Type: Report
System: The UNT Digital Library
Analytic, High-beta Solutions of the Helical Grad-Shafranov Equation (open access)

Analytic, High-beta Solutions of the Helical Grad-Shafranov Equation

We present analytic, high-beta ({beta} {approx} O(1)), helical equilibrium solutions for a class of helical axis configurations having large helical aspect ratio, with the helix assumed to be tightly wound. The solutions develop a narrow boundary layer of strongly compressed flux, similar to that previously found in high beta tokamak equilibrium solutions. The boundary layer is associated with a strong localized current which prevents the equilibrium from having zero net current.
Date: May 19, 2004
Creator: Smith, D. R. & Reiman, A. H.
Object Type: Report
System: The UNT Digital Library
Anchor Toolkit - a secure mobile agent system (open access)

Anchor Toolkit - a secure mobile agent system

Mobile agent technology facilitates intelligent operation insoftware systems with less human interaction. Major challenge todeployment of mobile agents include secure transmission of agents andpreventing unauthorized access to resources between interacting systems,as either hosts, or agents, or both can act maliciously. The Anchortoolkit, designed by LBNL, handles the transmission and secure managementof mobile agents in a heterogeneous distributed computing environment. Itprovides users with the option of incorporating their security managers.This paper concentrates on the architecture, features, access control anddeployment of Anchor toolkit. Application of this toolkit in a securedistributed CVS environment is discussed as a case study.
Date: May 19, 1999
Creator: Mudumbai, Srilekha S.; Johnston, William & Essiari, Abdelilah
Object Type: Article
System: The UNT Digital Library
Application of Electron Backscattered Diffraction (EBSD) and Atomic Force Microscopy (AFM) to Determine Texture, Microtexture, and Grain Boundary Energies in Ceramics (open access)

Application of Electron Backscattered Diffraction (EBSD) and Atomic Force Microscopy (AFM) to Determine Texture, Microtexture, and Grain Boundary Energies in Ceramics

Crystallographic orientations in alumina (Al<sub>2</sub>0<sub>3</sub>) and magnesium aluminate spinel (MgAl<sub>2</sub>0<sub>4</sub>) were obtained using electron backscattered diffraction (EBSD) patterns. The texture and mesotexture (grain boundary misorientations) were random and no special boundaries were observed. The relative grain boundary energies were determined by thermal groove geometries using atomic force microscopy (AFM) to identify relationships between the grain boundary energies and misorientations.
Date: May 19, 1999
Creator: Glass, S. J.; Rohrer, G. S.; Saylor, D. M. & Vedula, V. R.
Object Type: Article
System: The UNT Digital Library
Application of the TraPPE force field to predicting isothermal pressure-volume curves at high pressures and high temperatures (open access)

Application of the TraPPE force field to predicting isothermal pressure-volume curves at high pressures and high temperatures

Knowledge of the thermophysical properties of materials at extreme pressure and temperature conditions is essential for improving our understanding of many planetary and detonation processes. Significant gaps in what is known about the behavior of materials at high density and high temperature exist, largely due to the limitations and dangers of performing experiments at the necessary extreme conditions. Modeling these systems through the use of equations of state and particle-based simulation methods significantly extends the range of pressures and temperatures that can be safely studied. The reliability of such calculations depends on the accuracy of the models used. Here we present an assessment of the united-atom version of the TraPPE (Transferable Potentials for Phase Equilibria) force field and single-site exp-6 representations for methane, methanol, oxygen, and ammonia at extreme conditions. As shown by Monte Carlo simulations in the isobaric-isothermal ensemble, the TraPPE models, despite being parameterized to the vapor-liquid coexistence curve (i.e. relatively mild conditions), perform remarkably well in the high pressure/high temperature regime. The single-site exp-6 models can fit experimental data in the high pressure/temperature regime very well, but the parameters are less transferable to ambient conditions.
Date: May 19, 2006
Creator: Eggimann, B L; Siepmann, J I & Fried, L E
Object Type: Article
System: The UNT Digital Library
APPR critical experiment program meeting (open access)

APPR critical experiment program meeting

This report addresses the APPR critical experiment program meeting.
Date: May 19, 1955
Creator: Gallagher, J G
Object Type: Report
System: The UNT Digital Library
ASIC Development for Three-Dimensional Silicon Imaging Array for Cold Neutrons (open access)

ASIC Development for Three-Dimensional Silicon Imaging Array for Cold Neutrons

An Integrated Circuit (IC) readout chip with four channels arranged so as to receive input charge from the corners of the chip was designed for use with 5- to 7-mm pixel detectors. This Application Specific IC (ASIC) can be used for cold neutron imaging, for study of structural order in materials using cold neutron scattering or for particle physics experiments. The ASIC is fabricated in a 0.5-{micro}m n-well AMI process. The design of the ASIC and the test measurements made is reported. Noise measurements are also reported.
Date: May 19, 2004
Creator: Britton, C.L.; Jagadish, U. & Bryan, W.L.
Object Type: Report
System: The UNT Digital Library
Attack of stainless steel type 2169 by decomposition products of TATB studied by Auger spectroscopy and ESCA (open access)

Attack of stainless steel type 2169 by decomposition products of TATB studied by Auger spectroscopy and ESCA

None
Date: May 19, 1975
Creator: Colmenares, C.; Meisenheimer, R.; Smith, R.L. & Fischer, J.W.
Object Type: Article
System: The UNT Digital Library
Audit of Administration of Cooperative Research and Development Agreements at DOE National Laboratories (open access)

Audit of Administration of Cooperative Research and Development Agreements at DOE National Laboratories

DOE established policies to ensure that Cooperative Research and Development Agreements (CRADAS) enhance US competitiveness in the world economy, provide a reasonable return on resources invested, and enable successful commercialization of technologies developed. DOE`s Office of Technology Partnerships issued a General Guidance Memorandum to DOE operations offices establishing policy goals for technology transfer programs, including CRADAS. Our audit disclosed that efforts to manage CRADAs at three national laboratories did not fully achieve DOE`s policy goals outlined in the General Guidance Memorandum. Specifically, the audit showed that: (1) joint work statements did not always contain clearly defined information that allowed DOE to facilitate technology transfer or to evaluate CRADAs potential benefits; (2) CRADA statements of work did not always contain adequate documentation or address potential benefits; (3) the national laboratories reviewed did not have effective mechanisms for continuous self-appraisal or measures of overall program success; and (4) CRADA provisions did not exist to ensure an accurate evaluation of partner contributions.
Date: May 19, 1995
Creator: unknown
Object Type: Report
System: The UNT Digital Library
BEAM-BEAM 2003 SUMMARY. (open access)

BEAM-BEAM 2003 SUMMARY.

This paper summarizes the presentations and discussions of the Beam-Beam'03 workshop, held in Montauk, Long Island, from May 19 to 23, 2003. Presentations and discussions focused on halo generation from beam-beam interactions; beam-beam limits, especially coherent limits and their effects on existing and future hadron colliders; beam-beam compensation techniques, particularly for long-range interactions; and beam-beam study tools in theory, simulation, and experiment.
Date: May 19, 2003
Creator: FISCHER,W. SEN,T.
Object Type: Article
System: The UNT Digital Library
Beyond Finite Size Scaling in Solidification Simulations (open access)

Beyond Finite Size Scaling in Solidification Simulations

Although computer simulation has played a central role in the study of nucleation and growth since the earliest molecular dynamics simulations almost 50 years ago, confusion surrounding the effect of finite size on such simulations have limited their applicability. Modeling solidification in molten tantalum on the BlueGene/L computer, we report here on the first atomistic simulation of solidification that verifies independence from finite size effects during the entire nucleation and growth process, up to the onset of coarsening. We show that finite size scaling theory explains the observed maximal grain sizes for systems up to about 8,000,000 atoms. For larger simulations, a cross-over from finite size scaling to more physical size-independent behavior is observed.
Date: May 19, 2005
Creator: Streitz, F H; Glosli, J N & Patel, M V
Object Type: Article
System: The UNT Digital Library
Broad, intense, quiescent beam of singly charged metal ions obtained by extraction from self-sputtering plasma far above the runaway threshold (open access)

Broad, intense, quiescent beam of singly charged metal ions obtained by extraction from self-sputtering plasma far above the runaway threshold

Dense metal plasmas obtained by self-sputtering far above the runway threshold are well suited to generate intense quiescent ion beams. The dilemma of high current density and charge state purity can be solved when using target materials of low surface binding energy by utilizing non-resonant exchange reactions before ion extraction. Space-charge-limited quiescent beams of Cu+, Zn+, and Bi+ with ~;;10 mA/cm2 have been obtained through multi-aperture gridded ion extraction up to 45 kV from self-sputtering plasmas.
Date: May 19, 2009
Creator: Anders, Andre & Oks, Efim
Object Type: Article
System: The UNT Digital Library
Cable Hot Shorts and Circuit Analysis in Fire Risk Assessment (open access)

Cable Hot Shorts and Circuit Analysis in Fire Risk Assessment

Under existing methods of probabilistic risk assessment (PRA), the analysis of fire-induced circuit faults has typically been conducted on a simplistic basis. In particular, those hot-short methodologies that have been applied remain controversial in regards to the scope of the assessments, the underlying methods, and the assumptions employed. To address weaknesses in fire PRA methodologies, the USNRC has initiated a fire risk analysis research program that includes a task for improving the tools for performing circuit analysis. The objective of this task is to obtain a better understanding of the mechanisms linking fire-induced cable damage to potentially risk-significant failure modes of power, control, and instrumentation cables. This paper discusses the current status of the circuit analysis task.
Date: May 19, 1999
Creator: LaChance, Jeffrey; Nowlen, Steven P. & Wyant, Frank
Object Type: Article
System: The UNT Digital Library