States

A material model driver for DYNA3D (open access)

A material model driver for DYNA3D

This report describes a material model driver which has recently been implemented in the DYNA3D code. The material model driver allows plotting of the constitutive response predicted by a material model under a given load path. This capability is particularly useful when fitting complex material models to experimental data. The plotting capability of the material model driver facilitates comparison of the simulated material stress-strain behavior with actual material test results. 1 ref., 6 figs., 4 tabs.
Date: February 22, 1990
Creator: Hallquist, J.O. & Whirley, R.G.
Object Type: Report
System: The UNT Digital Library
Sector 30 collimator radiation (open access)

Sector 30 collimator radiation

The collimators at Sector 30 of the SLAC accelerator are designed to scrape off a significant fraction (e.g., {approximately}20%) of the SLC beam. The electromagnetic cascade shower that develops in the collimator, and in the scraper and waveguide downbeam, leads to very high radiation exposures of TV cameras (and other devices) located nearby. The collimator (point) source accounts for one-third of the dose and is best shielded by extending the radius of the copper scraper. Radiation from the waveguide accounts for the remaining two-thirds of the dose, and is difficult to shield since it is a line source. However, the spectrum from the waveguide is expected to be softer than that from the collimator. This paper discusses shielding of these sources.
Date: February 22, 1990
Creator: Namito, Y. (Ship Research Inst., Tokyo (Japan)); Nelson, W. R. & Benson, E.
Object Type: Report
System: The UNT Digital Library
Technical Appendix to Cryogenic Pressure Vessels (open access)

Technical Appendix to Cryogenic Pressure Vessels

The 20,000 gls. Liquid Argon dewar stores up to 15,000 gls. of high purity (<1.0 ppm O{sub 2}, 0.999995) LAr for use in the Liquid Argon calorimeters of E740, the D0 collider detector, at elevation 707-feet. The dewar provides for the total detector volume of 11,000 gls and a 4,000 gls. storage inventory. The large gas volume ({ge}5,000 gls.) serves operational needs and guards against overfill concerns. The LAr dewar functions in two modes: (1) low pressure (16 psi relief) storage, and liquid and gas transfer operations to and from the low pressure (13 psi relief) detector cryostats, and (2) high pressure (65 psi relief) liquid transfer operations to and from a delivery trailer at elevation 743-feet. The storage function is intended to be long term and nonventing. The dewar is equipped with a 40 kW LN{sub 2} condenser that operates to maintain the pressure constant in the storage mode. This service exactly parallels the NeH{sub 2} and D{sub 2} storage dewar services provided at the 15-feet bubble chamber for its operation.
Date: February 22, 1990
Creator: Mulholland, G. T. & Rucinski, R. A
Object Type: Report
System: The UNT Digital Library
Control Class Summaries and Control Class IV from April 1990 (open access)

Control Class Summaries and Control Class IV from April 1990

The D0 cryogenic control system is a complicated system with many facets. Because of the large number and variety of features in the system, a series of ongoing control system training seminars, or control classes, were created in order to keep people up to date on the operation of the system. As of the writing of this engineering note, there have been four classes. The original lecture notes from each class can be found in the cryogenic control room at the D0 Assembly Building, or in the Co-op office. This note provides a summary of the first three control classes, and it includes the entire set of notes from the fourth class, which was held in April of 1990. This class was taught by Jeff Wendlandt and Dan Markley. Dan should be consulted for more complete explanations than those given in the notes. The notes are, in fact, more of a reference for someone who has some experience with the system, than they are a training manual. Most of the pages include pictures and printouts of different menus and functions, useful for finding details without searching through the actual program. In general, this note serves as a pointer to the …
Date: February 22, 1991
Creator: Wu, J.
Object Type: Report
System: The UNT Digital Library
Design, synthesis, and characterization of novel fine-particle, unsupported catalysts for coal liquefaction (open access)

Design, synthesis, and characterization of novel fine-particle, unsupported catalysts for coal liquefaction

The first task in our proposed study of catalysts for coal liquefaction was to prepare ultrafine dispersed metal sulfide particles by reactive precipitation from solutions of appropriate metal precursors. At this point, equipment to allow us to prepare these air-sensitive materials in an anaerobic environment has been acquired and assembled. Initial experiments aimed at synthesizing iron sulfide particles have been initiated. As part of the investigation of short contact time catalytic coal liquefaction, initial efforts focused on the noncatalytic pyrolysis reactions of coal and a model compound, Dibenzyl ether (DBE). Two different reactor configurations were examined; catalytic experiments are planned for the coming month.
Date: February 22, 1991
Creator: Klein, M.T.
Object Type: Report
System: The UNT Digital Library
Design, synthesis, and characterization of novel fine-particle, unsupported catalysts for coal liquefaction. Technical progress report, October 26, 1990--January 26, 1991: Draft (open access)

Design, synthesis, and characterization of novel fine-particle, unsupported catalysts for coal liquefaction. Technical progress report, October 26, 1990--January 26, 1991: Draft

The first task in our proposed study of catalysts for coal liquefaction was to prepare ultrafine dispersed metal sulfide particles by reactive precipitation from solutions of appropriate metal precursors. At this point, equipment to allow us to prepare these air-sensitive materials in an anaerobic environment has been acquired and assembled. Initial experiments aimed at synthesizing iron sulfide particles have been initiated. As part of the investigation of short contact time catalytic coal liquefaction, initial efforts focused on the noncatalytic pyrolysis reactions of coal and a model compound, Dibenzyl ether (DBE). Two different reactor configurations were examined; catalytic experiments are planned for the coming month.
Date: February 22, 1991
Creator: Klein, M. T.
Object Type: Report
System: The UNT Digital Library
DSP: A detailed spectroscopy postprocessor for H-, He-, and Li-like ions (open access)

DSP: A detailed spectroscopy postprocessor for H-, He-, and Li-like ions

A detailed plasma spectroscopy postprocessor for H-, He-, and Li-like ions with 6 {le} Z {le} 26 has been constructed. The structure of the code and the physics contained within it will be described and a sample application given. 15 refs., 5 figs.
Date: February 22, 1991
Creator: Keane, C.J.; Lee, R.S. (Lawrence Livermore National Lab., CA (USA)) & Grandy, J.P. (Massachusetts Inst. of Tech., Cambridge, MA (USA))
Object Type: Article
System: The UNT Digital Library
(HFR-B1 experiment reporting and capsule disassembly) (open access)

(HFR-B1 experiment reporting and capsule disassembly)

The traveler visited the Joint Research Centre (JRC), Petten, The Netherlands, the Forschungszentrum GmbH (KFA), Juelich, Germany; and the Zentralinstitut fuer Kernforschung (ZfK), Rossendorf, Germany, during the period January 28 through February 9. At JRC, the analysis of the experiment HFR-B1 was discussed; a new schedule for issuance of the final data report was established. Other discussions at JRC concerned the capabilities of Petten to conduct two reactor experiments being proposed under the US/FRG cooperative program and the initial results of a proof test of Germany fuel spheres. At KFA, the main emphasis was on the disassembly of capsules 2 and 3 of the HFR-B1 experiment and agreement on the examinations and tests to be conducted with the disassembled components. The disassembly of capsule 3 was observed. Extensive discussions were conducted on the work, both experimental and analytical, being conducted in the Institut fuer Sicherheitsforschung und Reaktor Technologie. A major portion of the experimental work is being conducted at ZfK and a visit to this laboratory, sponosored by the KFA, was made on February 6 and 7. Cooperation with the US on the experimental and analytical work in the safety area was strongly emphasized. 1 tab.
Date: February 22, 1991
Creator: Myers, B.F.
Object Type: Report
System: The UNT Digital Library
Modeling the Longitudinal Wall Impedance Instability in Heavy Ion Beams Using an R-Z PIC Code (open access)

Modeling the Longitudinal Wall Impedance Instability in Heavy Ion Beams Using an R-Z PIC Code

The effects of the longitudinal wall impedance instability in a heavy ion beam are of great interest for heavy ion fusion drivers. We are studying this instability using the R-Z thread of the WARP PIC code. We describe the code and our model of the impedance due to the accelerating modules of the induction LINAC as a resistive wall. We present computer simulations which illustrate this instability. 2 refs., 2 figs., 1 tab.
Date: February 22, 1991
Creator: Callahan, D. A.; Langdon, A. B.; Friedman, A.; Grote, D. P. & Haber, I.
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: DM-4 (open access)

Texas Attorney General Opinion: DM-4

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether a county may make a purchase in excess of $10,000 without competitive bids if, after advertising, no bids are recieved (RQ-2187)
Date: February 22, 1991
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Register, Volume 16, Number 14, Pages 1107-1242, February 22, 1991 (open access)

Texas Register, Volume 16, Number 14, Pages 1107-1242, February 22, 1991

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: February 22, 1991
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Preventable Disease News, Volume 52, Number 4, February 22, 1992 (open access)

Texas Preventable Disease News, Volume 52, Number 4, February 22, 1992

Newsletter of the Texas Bureau of Disease Control and Epidemiology discussing the news, activities, and events of the organization and other information related to health in Texas.
Date: February 22, 1992
Creator: Texas. Bureau of Disease Control and Epidemiology.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Bulletin on Texas State Finance: 1993, Number 1 (open access)

Bulletin on Texas State Finance: 1993, Number 1

Periodic bulletin analyzing issues related to Texas legislation. This issue focuses on property values.
Date: February 22, 1993
Creator: Texas Research League
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Geographos asteroid flyby and autonomous navigation study (open access)

Geographos asteroid flyby and autonomous navigation study

Deep Space Program Science Experiment (DSPSE), also known as Clementine, is a collection of science experiments conducted in near-earth with the goal of demonstrating Strategic Defense Initiative Office (SDIO) developed technologies. The 785 lb (fully fueled) spacecraft will be launched into low Earth orbit in February 1994 together with a Star 37 solid kick motor and interstage. After orbit circulation using Clementine`s 110 lb Delta-V thruster, the Star 37 will execute a trans-lunar injection burn that will send the spacecraft toward lunar obit. The 110-lb will then be used in a sequence of burns to insert Clementine into a trimmed, polar orbit around the moon. After a two month moon mapping mission, Clementine will execute burns to leave lunar orbit, sling-shot around Earth, and flyby the moon on a 9.4 million km journey toward the asteroid Geographos. After about three months in transit, Clementine will attempt a flyby with a closest point of approach of 100 km from the asteroid on August 31, 1994. During its approach to Geographos, Clementine will be tracked by the Deep Space Network (DSN) and receive guidance updates. The last update and correction burn will occur about one day out of the flyby. Multiple experiments …
Date: February 22, 1993
Creator: Ng, L. C.; Pines, D. J.; Patz, B. J. & Perron, D. C.
Object Type: Article
System: The UNT Digital Library
Longitudinal beam dynamics for heavy ion fusion using WARPrz (open access)

Longitudinal beam dynamics for heavy ion fusion using WARPrz

WARPrz is a 2.5 dimensional, cylindrically symmetric, electrostatic, particle-in-cell code. It is part of the WARP family of codes which has been developed to study heavy ion fusion driver issues. WARPrz is being used to study the longitudinal dynamics of heavy ion beams including a longitudinal instability that is driven by the impedance of the LINAC accelerating modules. This instability is of concern because it can enhance longitudinal momentum spread; chromatic abhoration in the lens system restricts the amount of momentum spread allowed in the beam in the final focusing system. The impedance of the modules is modeled by a continuum of resistors and capacitors in parallel in WARPrz. We discuss simulations of this instability including the effect of finite temperature and reflection of perturbations off the beam ends. We also discuss intermittency of axial confining fields (``ears`` fields) as a seed for this instability.
Date: February 22, 1993
Creator: Callahan, D. A.; Langdon, A. B.; Friedman, A. & Haber, I.
Object Type: Article
System: The UNT Digital Library
Model building, control and optimization of large scale systems (open access)

Model building, control and optimization of large scale systems

This report covers the research progress made during the calendar year 1992. The new results obtained during this period are described, keyed to the references listed on the last two pages of this report.
Date: February 22, 1993
Creator: Basar, T.
Object Type: Report
System: The UNT Digital Library
Model building, control and optimization of large scale systems. Progress report, January 1992--January 1993 (open access)

Model building, control and optimization of large scale systems. Progress report, January 1992--January 1993

This report covers the research progress made during the calendar year 1992. The new results obtained during this period are described, keyed to the references listed on the last two pages of this report.
Date: February 22, 1993
Creator: Basar, T.
Object Type: Report
System: The UNT Digital Library
Overview of WARP, a particle code for Heavy Ion Fusion (open access)

Overview of WARP, a particle code for Heavy Ion Fusion

The beams in a Heavy Ion beam driven inertial Fusion (HIF) accelerator must be focused onto small spots at the fusion target, and so preservation of beam quality is crucial. The nonlinear self-fields of these space-charge-dominated beams can lead to emittance growth; thus a self-consistent field description is necessary. We have developed a multi-dimensional discrete-particle simulation code, WARP, and are using it to study the behavior of HIF beams. The code`s 3d package combines features of an accelerator code and a particle-in-cell plasma simulation, and can efficiently track beams through many lattice elements and around bends. We have used the code to understand the physics of aggressive drift-compression in the MBE-4 experiment at Lawrence Berkeley Laboratory (LBL). We have applied it to LBL`s planned ILSE experiments, to various ``recirculator`` configurations, and to the study of equilibria and equilibration processes. Applications of the 3d package to ESQ injectors, and of the r, z package to longitudinal stability in driver beams, are discussed in related papers.
Date: February 22, 1993
Creator: Friedman, A.; Grote, D. P.; Callahan, D. A.; Langdon, A. B. & Haber, I.
Object Type: Article
System: The UNT Digital Library
A Performance Review of Austin Independent School District (ISD), February 1993 (open access)

A Performance Review of Austin Independent School District (ISD), February 1993

A performance review of Austin Independent School District (ISD) examining their use of funds in different areas of the school system.
Date: February 22, 1993
Creator: Texas. Comptroller's Office.
Object Type: Report
System: The Portal to Texas History
PIC space-charge emission with finite {Delta}t and {Delta}z (open access)

PIC space-charge emission with finite {Delta}t and {Delta}z

A new algorithm for space charge emission has been developed to provide the correct (to a few percent) Child-Langmuir steady-state current limits as the number of mesh points in the voltage gap drops to O(10). Further, the transient behavior of such flows compares well with idealized, analytic cases, lending confidence as we extend these algorithms into full RZ geometry with curved emitting surfaces to investigate transient characteristics of realistic injector designs.
Date: February 22, 1993
Creator: Hewett, D. W. & Chen, Yu-Jiuan
Object Type: Article
System: The UNT Digital Library
Precision of source response inside dimpled HAD brass tubes (open access)

Precision of source response inside dimpled HAD brass tubes

We have measured the variation in response of the {sup 137}CS source as positioned in 10 samples of the brass source tubes, dimpled at {plus_minus}5 cm from the center of a scintillator tile. We find an RMS in the signals of 2.5%.
Date: February 22, 1993
Creator: Jankowski, D. J. & Stanek, R.
Object Type: Report
System: The UNT Digital Library
Precision of source response inside dimpled HAD brass tubes (open access)

Precision of source response inside dimpled HAD brass tubes

We have measured the variation in response of the [sup 137]CS source as positioned in 10 samples of the brass source tubes, dimpled at [plus minus]5 cm from the center of a scintillator tile. We find an RMS in the signals of 2.5%.
Date: February 22, 1993
Creator: Jankowski, D. J. & Stanek, R.
Object Type: Report
System: The UNT Digital Library
Texas Disease Prevention News, Volume 53, Number 4, February 1993 (open access)

Texas Disease Prevention News, Volume 53, Number 4, February 1993

Newsletter of the Texas Department of Health discussing the news, activities, and events of the organization and other information related to health in Texas.
Date: February 22, 1993
Creator: Texas. Department of Health.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Pecan Pest Management Newsletter, Volume 93, Number 1, February 1993 (open access)

Texas Pecan Pest Management Newsletter, Volume 93, Number 1, February 1993

Newsletter focusing on pecan disease and pest control in Texas, including prevention, identification, treatment, and educational opportunities.
Date: February 22, 1993
Creator: Texas Agricultural Extension Service
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History