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Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces (open access)

Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Object Type: Report
System: The UNT Digital Library
The MTX (Microwave Tokamak Experiment) data acquisition system (open access)

The MTX (Microwave Tokamak Experiment) data acquisition system

The diagnostic data from the MTX experiment is acquired and processed by an expandable, distributed, multivendor computer network. The system blends a variety of software into a coordinated, unified, and highly flexible design. Using modular software design techniques, we created a system stressing distributed processing, portability, and transparent data access. In our approach to modularity, we standardized communication interfaces between modules and separated generic tasks from machine and application-specific implementations. For flexible distributed processing, we used modular, portable software and LLNL facility that provides an interprocess communication system (IPCS) in the multivendor network. With transparent data access, any program can access data stored anywhere in the network without knowing the specific location. The computer hardware includes a DEC VAX cluster, HP workstations and HP desktop computers. We are using commercial software in addition to packages from MIT, ORNL, and LLNL. 4 refs., 4 figs.
Date: September 20, 1989
Creator: Butner, D. N.; Drlik, M.; Brown, M. D.; Casper, T. A.; Meyer, W. H. & Moller, J. M.
Object Type: Article
System: The UNT Digital Library
Selective emitter. Task II topical report for radiative-cooling materials (open access)

Selective emitter. Task II topical report for radiative-cooling materials

The theoretical basis of the selective emitter is that, if a material emits only in the 8-13 micron interval, it will absorb only in the same interval. After a survey of several candidate materials, the silicon oxynitride system was found to have better optical properties than previously used materials as well as economic feasibility, and efforts to acquire a sample are described. Other promising materials are described: polyvinylidene fluoride (Tedlar), silicon monoxide, silicon dioxide, and silicon nitride. (LEW)
Date: September 20, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Analysis of quench-vent pressures for present design of ITER (International Thermonuclear Experimental Reactor) TF (toroidal field) coils (open access)

Analysis of quench-vent pressures for present design of ITER (International Thermonuclear Experimental Reactor) TF (toroidal field) coils

The International Thermonuclear Experimental Reactor (ITER) is a new tokamak design project with joint participation from Japan, the European Community, the Union of the Soviet Union, and the United States. This paper examines the effects of a quench within the toroidal field (TF) coils based on current ITER design. It is a preliminary, rough analysis. Its intent is to assist ITER designers while more accurate computer codes are being developed and to provide a check against these more rigorous solutions. Rigorous solutions to the quench problem are very complex involving three- dimensional heat transfer, extreme changes in heat capacities and copper resistivity, and varying flow dynamics within the conductors. This analysis addresses all these factors in an approximate way. The result is much less accurate than a rigorous analysis. Results here could be in error as much as 30 to 40 percent. However, it is believed that this paper can still be very useful to the coil designer. Coil pressures and temperatures vs time into a quench are presented. Rate of helium vent, energy deposition in the coil, and depletion of magnetic stored energy are also presented. Peak pressures are high (about 43 MPa). This is due to the very …
Date: September 20, 1989
Creator: Slack, D.S.
Object Type: Article
System: The UNT Digital Library
Recommendations for a cryogenic system for ITER (International Thermonuclear Experimental Reactor) (open access)

Recommendations for a cryogenic system for ITER (International Thermonuclear Experimental Reactor)

The International Thermonuclear Experimental Reactor (ITER) is a new tokamak design project with joint participation from Japan, the European Community, the Soviet Union, and the United States. ITER will be a large machine requiring up to 100 kW of refrigeration at 4.5 K to cool its superconducting magnets. Unlike earlier fusion experiments, the ITER cryogenic system must handle pulse loads constituting a large percentage of the total load. These come from neutron heating during a fusion burn and from ac losses during ramping of current in the PF (poloidal field) coils. This paper presents a conceptual design for a cryogenic system that meets ITER requirements. It describes a system with the following features: Only time-proven components are used. The system obtains a high efficiency without use of cold pumps or other developmental components. High reliability is achieved by paralleling compressors and expanders and by using adequate isolation valving. The problem of load fluctuations is solved by a simple load-leveling device. The cryogenic system can be housed in a separate building located at a considerable distance from the ITER core, if desired. The paper also summarizes physical plant size, cost estimates, and means of handling vented helium during magnet quench. 4 …
Date: September 20, 1989
Creator: Slack, D.S.
Object Type: Article
System: The UNT Digital Library
Precision timing and interlocks systems for FEL (free-electron laser) heating experiments on MTX (Microwave Tokamak Experiment) (open access)

Precision timing and interlocks systems for FEL (free-electron laser) heating experiments on MTX (Microwave Tokamak Experiment)

A new precision timing system has been installed on the Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL). The purpose of the system is to synchronize the tokamak's plasma discharge with a 140-GHz, 2-GW microwave pulse generated by a free-electron laser (FEL). The installation involved modifying the existing sequencer system and adding Digital delay generators, three in-house-designed CAMAC modules and other components. The system controls placement of the 30-ns FEL pulse during the MTX plasma discharge. It also provides precision triggers for the microwave plasma diagnostics. These triggers are distributed over 100-Mbit/s fiber-optic links. The MTX interlock system has been expanded to provide personnel safety during FEL experiments, to protect the FEL and related equipment, and to control the path of the FEL beam starting from the FEL's output, through the beam transport system, and into the tokamak. This paper describes how the existing MTX timing and interlocks systems were upgraded to accommodate these new FEL experiments. 4 refs., 4 figs.
Date: September 20, 1989
Creator: Petersen, D.E. (Lawrence Livermore National Lab., CA (USA))
Object Type: Article
System: The UNT Digital Library
Milliwatt-generator heat source. Progress report, January-June 1983 (open access)

Milliwatt-generator heat source. Progress report, January-June 1983

Progress is reported in the following: heat source shipments, reimbursable orders, hardware shipments, raw material qualification/procurement, DOE audit and milliwatt generator process review, surveillance capsule evaluations, pressure burst testing, and hardware fabrication and quality. (MHR)
Date: September 20, 1983
Creator: Mershad, E.A.
Object Type: Report
System: The UNT Digital Library
Microwave tokamak experiment (MTX) first year of operation and future plans (open access)

Microwave tokamak experiment (MTX) first year of operation and future plans

The Microwave Tokamak Experiment (MTX) at Lawrence Livermore National Laboratory (LLNL) began plasma operations in November 1988, and our main goal is the study of electron-cyclotron heating (ECH) in plasma discharges. The MTX tokamak was relocated from the Massachusetts Institute of Technology (MIT), and we have re-created plasma parameters that are similar to those generated while the tokamak was at MIT. After stable ohmic operation was achieved, single-pulse FEL heating experiments began. During this phase, the FEL operated at low power levels on the way to its ultimate goal of 2 GW and 140 GHz with a 30-ns pulse length. We have developed a number of new diagnostics to measure these fast FEL pulses and the resulting plasma effects. In this paper, we present results that show the correlation of MTX data with MIT data, some of the operational modifications and procedures used, results to date from preliminary tokamak operations with the FEL, and our near-term operational plans. 7 refs., 8 figs., 1 tab.
Date: September 20, 1989
Creator: Jackson, M.C.
Object Type: Article
System: The UNT Digital Library
Comparison of three ICF reactor designs (open access)

Comparison of three ICF reactor designs

Three concepts for inertial confinement fusion (ICF) reactors are described and compared with each other, and with magnetic fusion and fission reactors on the basis of environmental impact, safety and efficiency. The critical technical developments of each concept are described. The three concepts represent alternative development paths for inertial fusion.
Date: September 20, 1984
Creator: Hogan, W.J.
Object Type: Article
System: The UNT Digital Library
BX in-situ oil-shale project. Quarterly technical progress report, June 1, 1981-August 31, 1981 (open access)

BX in-situ oil-shale project. Quarterly technical progress report, June 1, 1981-August 31, 1981

June 1, 1981-August 31, 1981 was the third consecutive quarter of superheated steam injection at the BX In Situ Oil Shale Project. Injection was continuous except for the period of July 14th to August 1st when the injection was suspended during the drilling of core hole BX-37. During the quarter, 99,760 barrels of water as superheated steam were injected into Project injection wells at an average well head temperature of 752/sup 0/F and an average wellhead pressure of 1312 PSIG. During the same period, 135,469 barrels of fluid were produced from the Project production wells for a produced to injected fluid ratio of 1.36 to 1.0. Net oil production during the quarter was 38 barrels.
Date: September 20, 1981
Creator: Dougan, P. M.
Object Type: Report
System: The UNT Digital Library
Performance of cable-in-conduit conductors in ITER (International Thermonuclear Experimental Reactor) toroidal field coils with varying heat loads (open access)

Performance of cable-in-conduit conductors in ITER (International Thermonuclear Experimental Reactor) toroidal field coils with varying heat loads

The toroidal field (TF) coils in the International Thermonuclear Experimental Reactor (ITER) will operate with varying heat loads generated by ac losses and nuclear heating. The total heat load is estimated to be 2 kW per TF coil under normal operation and can be higher for different operating scenarios. Ac losses are caused by ramping the poloidal field (PF) for plasma initiation, burn, and shutdown; nuclear heating results from neutrons that penetrate into the coil past the shield. Present methods to reduce or eliminate these losses lead to larger and more expensive machines, which are unacceptable with today's budget constraints. A suitable solution is to design superconductors that operate with high heat loads. The cable-in-conduit conductor (CICC) can operate with high heat loads. One CICC design is analyzed for its thermal performance using two computer codes developed at LLNL. One code calculates the steady state flow conditions along the flow path, while the other calculates the transient conditions in the flow. We have used these codes to analyze the superconductor performance during the burn phase of the ITER plasma. The results of these analyses give insight to the choice of flow rate on superconductor performance. 4 refs., 5 figs.
Date: September 20, 1989
Creator: Kerns, J.A. & Wong, R.L.
Object Type: Article
System: The UNT Digital Library
A non-inductively driven steady state tokamak reactor (open access)

A non-inductively driven steady state tokamak reactor

The physics and engineering guidelines for the ITER device are shown to lead to viable and attractive operating points for a steady state tokamak power reactor. Non-inductive current drive is provided in steady state by high energy neutral beam injection in the plasma core, lower hybrid slow waves in the outer regions of the plasma and bootstrap current. Plasma gain Q (/equivalent to/fusion power/input power) in excess of 20 and average neutron wall loading, <GAMMA> approx. 2.0 MW/m/sup 2/ are predicted in a device with major radius, R/sub 0/ = 7.5 m and minor radius, a = 2.8 m. 15 refs., 3 figs., 3 tabs.
Date: September 20, 1988
Creator: Fenstermacher, M. E.; Devoto, R. S.; Bulmer, R. H.; Lee, J. D.; Miller, J. R. & Schultz, J.
Object Type: Article
System: The UNT Digital Library
Third order TRANSPORT with MAD (Methodical Accelerator Design) input (open access)

Third order TRANSPORT with MAD (Methodical Accelerator Design) input

This paper describes computer-aided design codes for particle accelerators. Among the topics discussed are: input beam description; parameters and algebraic expressions; the physical elements; beam lines; operations; and third-order transfer matrix. (LSP)
Date: September 20, 1988
Creator: Carey, D.C.
Object Type: Report
System: The UNT Digital Library
SIMS and ESCA studies of possible sodium uranate precursors as related to aerosol characterization from a simulated HCDA. [LMFBR] (open access)

SIMS and ESCA studies of possible sodium uranate precursors as related to aerosol characterization from a simulated HCDA. [LMFBR]

During the main thrust of the HCDA studies, it was found that sodium uranates, especially Na/sub 3/UO/sub 4/, were formed when the Na-U-O system was subjected to high temperatures approximating those of the HCDA. Mechanisms through which these rather complicated compounds are formed remain unknown. The purpose of these SIMS and ESCA studies was to detect the formation of any precursor ion species to the sodium uranates. The ESCA results agree with theory and support the presence of U/sub 2/O/sub 7/ /sup 2 -/ in Na/sub 2/U/sub 2/O/sub 7/; however, SIMS analyses show no evidence of possible uranate precursor formation in an Ar/sup +/ sputtered ion beam.
Date: September 20, 1982
Creator: Zanotelli, W. A. Jr.; Miller, G. D. & Craven, S. M.
Object Type: Report
System: The UNT Digital Library
Continuous cryopump for steady-state Mirror Fusion Reactors (open access)

Continuous cryopump for steady-state Mirror Fusion Reactors

The characteristics of Mirror Fusion Reactors, i.e., steady state operation, a low neutral gas density and a large gas throughput require unique vacuum pumping capabilities. One approach that appears to meet these requirements is a liquid helium cooled cryopump system in which a fixed portion can be isolated and degassed while the remainder continues to pump. The time to degas a rotating, fixed portion of the pumping area and the ratio of that area to the total area fixes the gas inventory in the chamber. It follows that the active pump area maintains the required neutral gas density and the time averaged degassing rate equals the gas throughput. We have built such a cryopump whereby the gas condensed (deuterium) on the liquid helium cooled panel can be transferred to a collector pump and subsequently to an exterior mechanical pump and exhausted. At panel loadings as high as .55 torr-litres/cm/sup 2/ the gas leakage during degassing is less than 8% and the degassing time is less than 10 minutes. Scaling to reactor size appears to be feasible.
Date: September 20, 1982
Creator: Batzer, T. H. & Call, W. R.
Object Type: Article
System: The UNT Digital Library
Texas Register, Volume 10, Number 70, Pages 3569-3644, September 20, 1985 (open access)

Texas Register, Volume 10, Number 70, Pages 3569-3644, September 20, 1985

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: September 20, 1985
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Register, Volume 8, Number 69, Pages 3723-3770, September 20, 1983 (open access)

Texas Register, Volume 8, Number 69, Pages 3723-3770, September 20, 1983

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: September 20, 1983
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Attorney General Opinion: LO89-74 (open access)

Texas Attorney General Opinion: LO89-74

Letter opinion 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, Jim Mattox, regarding a legal question submitted for clarification.
Date: September 20, 1989
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JM-1097 (open access)

Texas Attorney General Opinion: JM-1097

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, Jim Mattox, regarding a legal question submitted for clarification;Whether Johnson county has the option of creating a county industrial commission instead of a board of development(RQ-1692).
Date: September 20, 1989
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JM-1099 (open access)

Texas Attorney General Opinion: JM-1099

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, Jim Mattox, regarding a legal question submitted for clarification;Whether a county auditor may require elected officials and department heads to provide details about employees hours worked and leave taken(RQ-1548).
Date: September 20, 1989
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Mineral resources of the Fiddler Butte (East) Wilderness Study Area, Garfield County, Utah (open access)

Mineral resources of the Fiddler Butte (East) Wilderness Study Area, Garfield County, Utah

Map showing the mineral resource potential and the geology of the Fiddler Butte Wilderness Study Area
Date: September 20, 1989
Creator: Dubiel, Russell F.; Gese, Diann D.; Lee, Gregory K. & Orkild, Paul P.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 13, Number 72, Pages 4619-4703, September 20, 1988 (open access)

Texas Register, Volume 13, Number 72, Pages 4619-4703, September 20, 1988

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: September 20, 1988
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Control algorithms for autonomous robot navigation (open access)

Control algorithms for autonomous robot navigation

This paper examines control algorithm requirements for autonomous robot navigation outside laboratory environments. Three aspects of navigation are considered: navigation control in explored terrain, environment interactions with robot sensors, and navigation control in unanticipated situations. Major navigation methods are presented and relevance of traditional human learning theory is discussed. A new navigation technique linking graph theory and incidental learning is introduced.
Date: September 20, 1985
Creator: Jorgensen, C. C.
Object Type: Article
System: The UNT Digital Library
Texas Parks & Wildlife News, September 20, 1989 (open access)

Texas Parks & Wildlife News, September 20, 1989

Weekly newsletter discussing natural resources, parks, hunting and fishing, and other information related to the outdoors in Texas.
Date: September 20, 1989
Creator: Texas. Parks and Wildlife Department.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History