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A 6.7 MeV cw RFQ linac (open access)

A 6.7 MeV cw RFQ linac

A 6.7-MeV 350 MHz, cw Radio Frequency Quadrupole proton linac has been designed and is being fabricated for the Accelerator Production of Tritium Project at Los Alamos. This eight-meter long structure consists of four resonantly-coupled segments and is being fabricated using hydrogen furnace brazing as a joining technology. Details of the design and status of fabrication are reported.
Date: August 1, 1997
Creator: Schrage, D.; Young, L.; Clark, W.; Davis, T.; Martinez, F.; Naranjo, A. et al.
Object Type: Article
System: The UNT Digital Library
24 M Meteorological Tower Data Report Period: January--December, 1994 (open access)

24 M Meteorological Tower Data Report Period: January--December, 1994

This report was prepared by the Desert Research Institute (DRI) for the U.S. Department of Energy (DOE). It summarizes meteorological data collected at the 24 meter tower at the Nevada Test Site Hazardous Material Spill Center (HAZMAT) located at Frenchman Flat near Mercury, Nevada, approximately 75 miles northwest of Las Vegas, Nevada. The tower was originally installed in July, 1993 to characterize baseline conditions for an EPA sponsored experimental research program at the HAZMAT.
Date: August 1, 1997
Creator: Freeman, D.; Bowen, J. & Egami, R.
Object Type: Report
System: The UNT Digital Library
94-1 Research and development project lead laboratory support. Status report, January 1--March 31, 1997 (open access)

94-1 Research and development project lead laboratory support. Status report, January 1--March 31, 1997

This status report is published for Los Alamos National Laboratory 94-1 Research and Development Project Support. The Department of Energy Office of Environmental Management funds these projects in order to support the storage or disposal of legacy plutonium and plutonium-bearing materials that resulted from weapons production throughout the DOE complex. This report summarizes status and technical progress for Los Alamos 94-1 projects during the second quarter of fiscal year 1997.
Date: August 1, 1997
Creator: Rink, N.A.
Object Type: Report
System: The UNT Digital Library
1400 Liter 1.8K Test Facility (open access)

1400 Liter 1.8K Test Facility

A double bath superfluid helium dewar has been constructed and operated at Fermilab`s Magnet Test Facility. The 1.8 K portion of the dewar is sized to contain a superconducting magnet up to 0.5 meters in diameter and 4 meters long in a vertical orientation in 0.12 MPa pressurized superfluid. The dewar can also provide a subcooled Helium I environment for tests; the entire temperature range from 4.4 K to 1. 8 K at 0.12 MPa is available. This paper describes the system design, lambda plate, heat exchanger, and performance.
Date: August 1, 1997
Creator: Peterson, T. J.; Rabehl, R. J. & Sylvester, C. D.
Object Type: Article
System: The UNT Digital Library
1996 Site environmental report Sandia National Laboratories Albuquerque, New Mexico (open access)

1996 Site environmental report Sandia National Laboratories Albuquerque, New Mexico

Sandia National Laboratories/New Mexico (SNL/NM) is operated in support of the U.S. Department of Energy (DOE) mission to provide weapon component technology and hardware for national security needs, and to conduct fundamental research and development (R&D) to advance technology in energy research, computer science, waste management, electronics, materials science, and transportation safety for hazardous and nuclear components. In support of this mission, the Environmental Safety and Health (ES&H) Center at SNL/NM conducts extensive environmental monitoring, surveillance, and compliance activities to assist SNL`s line organizations in meeting all applicable environmental regulations applicable to the site including those regulating radiological and nonradiological effluents and emissions. Also herein are included, the status of environmental programs that direct and manage activities such as terrestrial surveillance; ambient air and meteorological monitoring; hazardous, radioactive, and solid waste management; pollution prevention and waste minimization; environmental restoration (ER); oil and chemical spill prevention; and National Environmental Policy Act (NEPA) documentation. This report has been prepared in compliance with DOE order 5400.1, General Environmental Protection.
Date: August 1, 1997
Creator: Fink, C.H.; Duncan, D. & Sanchez, R.
Object Type: Report
System: The UNT Digital Library
1996 Site environmental report Tonopah test range Tonopah, Nevada (open access)

1996 Site environmental report Tonopah test range Tonopah, Nevada

Sandia National Laboratories (SNL) operates the Tonopah Test Range (TTR) for the Department of Energy`s (DOE) Weapons Ordnance Program. This annual report (calendar year 1996) summarizes the compliance status to environmental regulations applicable at the site including those statutes that govern air and water quality, waste management, clean-up of contaminated areas, control of toxic substances, and adherence to requirements as related to the National Environmental Policy Act (NEPA). In compliance with DOE Orders, SNL also conducts environmental surveillance for radiological and nonradiological contaminants. SNL`s responsibility for environmentals surveillance for radiological and nonradiological contaminants. SNL`s responsibility for environmental surveillance extends only to those activities performed by SNL or under its direction. Annual radiological and nonradiological routine releases and unplanned releases (occurrences) are also summarized herein.
Date: August 1, 1997
Creator: Culp, T.; Forston, W.; Duncan, D. & Sanchez, R.
Object Type: Report
System: The UNT Digital Library
Abnormal grain growth -- The origin of recrystallization nuclei? (open access)

Abnormal grain growth -- The origin of recrystallization nuclei?

The origin of recrystallization nuclei is reviewed with particular emphasis on materials in which well-developed cells are present in the deformed state. Nucleation is discussed in terms of coarsening of the subgrain network that develops on annealing and an analogy is made with abnormal grain growth. The results of a theoretical analysis of abnormal growth are summarized. The Monte Carlo model for grain growth is adapted for variable grain boundary energy and mobility in order to investigate the behavior of individual grains with special properties. The simulation results show that both energy and mobility affect abnormal growth as expected from the theoretical analysis. The results are discussed in terms of the stability that subgrain networks may exhibit depending on their mean misorientation.
Date: August 1, 1997
Creator: Rollett, A. D. & Holm, E. A.
Object Type: Report
System: The UNT Digital Library
Access control and interlock system at the Advanced Photon Source (open access)

Access control and interlock system at the Advanced Photon Source

The Advanced Photon Source (APS) consists of a linac, position accumulator ring (PAR), booster synchrotron, storage ring, and up to 70 experimental beamlines. The Access Control and Interlock System (ACIS) utilizes redundant programmable logic controllers (PLCs) and a third hard-wired chain to protect personnel from prompt radiation generated by the linac, PAR, synchrotron, and storage ring. This paper describes the ACIS`s design philosophy, configuration, hardware, functionality, validation requirements, and operational experience.
Date: August 1, 1997
Creator: Forrestal, J.; Hogrefe, R.; Knott, M.; McDowell, W.; Reigle, D.; Solita, L. et al.
Object Type: Article
System: The UNT Digital Library
Achievement of a superpolish on bare stainless steel (open access)

Achievement of a superpolish on bare stainless steel

We report the achievement of a superpolished surface, suitable for x-ray reflection, on bare stainless steel. The rms roughness obtained on various samples varied from 2.2 to 4.2 {angstrom}, as measured by an optical profiler with a bandwidth 0.29-100 mm{sup -1}. The type 17-4 PH precipitation-hardening stainless steel used to make the mirrors is also capable of ultrastability and has good manufactureability. This combination of properties makes it an excellent candidate material for mirror substrates. We describe the successful utilization of this type of steel in making elliptical-cylinder mirrors for a soft-x-ray microprobe system at the Advanced Light Source, and discuss possible for its unusual stability and polishability.
Date: August 1, 1997
Creator: Howells, M.R. & Casstevens, J.
Object Type: Article
System: The UNT Digital Library
Active chatter control in a milling machine (open access)

Active chatter control in a milling machine

The use of active feedback compensation to mitigate cutting instabilities in an advanced milling machine is discussed in this paper. A linear structural model delineating dynamics significant to the onset of cutting instabilities was combined with a nonlinear cutting model to form a dynamic depiction of an existing milling machine. The model was validated with experimental data. Modifications made to an existing machine model were used to predict alterations in dynamics due to the integration of active feedback compensation. From simulations, subcomponent requirements were evaluated and cutting enhancements were predicted. Active compensation was shown to enable more than double the metal removal rate over conventional milling machines. 25 refs., 10 figs., 1 tab.
Date: August 1, 1997
Creator: Dohner, J. L.; Hinnerichs, T. D. & Lauffer, J. P.
Object Type: Article
System: The UNT Digital Library
The activity of cobalt and silicon in the Co - Si system with special focus on the {alpha} - Co solid solution (open access)

The activity of cobalt and silicon in the Co - Si system with special focus on the {alpha} - Co solid solution

The activities of cobalt and silicon at 1463 K have been determined across the whole composition range in the Co - Si system, including the {alpha} - Co solid solution, for which no activity data were previously available. Simple and reactive Knudsen effusion mass spectroscopy employed in this work were shown to successfully overcome problems normally encountered in studying high-temperature solid binary systems, such as slow equilibration and low partial pressures of the components. The composition dependence of the cobalt activities within the {alpha} - Co solid solution phase was used to calculate the self-interaction coefficients of silicon in {alpha} - Co: ln {gamma}{sub Si} = 10.4 {+-} 0.2 and {epsilon}{sub Si}{sup (Si)} = 18.6 {+-} 0.8. The regular solution model was shown to be a fairly good description of the {alpha} - Co solid solution, with an energy parameter Z{sub CoSi} of -120 {+-} 5 kJ{center_dot}mol{sup -1}. The results compare well with literature data on similar systems, such as Fe - Si and Ni - Si.
Date: August 1, 1997
Creator: Lexa, D.; Kematick, R. J. & Myers, C. E.
Object Type: Article
System: The UNT Digital Library
Adaptive Mesh Refinement Algorithm Development and Dissemination (open access)

Adaptive Mesh Refinement Algorithm Development and Dissemination

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to develop and disseminate adaptive mesh refinement (AMR) algorithms for structured and unstructured meshes. Development of ARM algorithms will continue along several directions. These directions include algorithms for parallel architectures, techniques for the solution of partial differential equations on adaptive meshes, mesh generation, and algorithms for nontraditional or generic applications of AMR. Dissemination of AMR algorithms is also a goal of the project. AMR algorithms are perceived as difficult to meld to current algorithms. The authors are developing tools that diminish this perception and allow more computational scientists to use AMR within their own work.
Date: August 1, 1997
Creator: Saltzman, J.S.; Brown, D.L.; Brislawn, K.D.; Chesshire, G.S.; Quinlan, D.J. & Berger, M.
Object Type: Report
System: The UNT Digital Library
Adsorption on nanosurfaces: A detailed look at metal clusters using infrared spectroscopy (open access)

Adsorption on nanosurfaces: A detailed look at metal clusters using infrared spectroscopy

A technique known as infrared photodissociation spectroscopy is being used at Argonne to probe the intimate details of how molecules and atoms adsorb onto metal clusters. Clusters of transition metal atoms, produced by laser vaporization of a metal target, are allowed to react with small molecules, producing cluster complexes whose properties mimic those of the small metal-containing particles that make up many industrial catalysts. A powerful infrared laser is used to excite the characteristic vibrations of the atoms or molecules adsorbed on the surfaces of the clusters, causing the complexes to fragment. The resulting photodissociation spectrum is capable of revealing whether the adsorbed molecules have undergone a chemical reaction after sticking to the cluster surface. This techniques has been used to show that methyl alcohol molecules readily adsorb to the surfaces of small iron clusters, but do not undergo further reaction once they are there. This behavior is fundamentally different from that observed on macroscopic iron surfaces, where methyl alcohol readily reacts to form smaller fragment species. It is anticipated that these experiments will contribute to the understanding of particle size effects and their influence on reaction mechanisms and pathways in heterogeneous catalysis systems.
Date: August 1, 1997
Creator: Knickelbein, M.B.
Object Type: Report
System: The UNT Digital Library
Advanced Biomass Gasification Projects (open access)

Advanced Biomass Gasification Projects

DOE has a major initiative under way to demonstrate two high-efficiency gasification systems for converting biomass into electricity. As this fact sheet explains, the Biomass Power Program is cost-sharing two scale-up projects with industry in Hawaii and Vermont that, if successful, will provide substantial market pull for U.S. biomass technologies, and provide a significant market edge over competing foreign technologies.
Date: August 1, 1997
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Advanced concurrent engineering environment final report (open access)

Advanced concurrent engineering environment final report

Sandia demonstrated large-scale visualization in a conference room environment. Project focused on the installation of hardware for visualization and display, and the integration of software tools for design and animation of 3-dimensional parts. Using a high-end visualization server, 3-dimensional modeling and animation software, and leading edge World Wide Web technology, and advanced concurrent engineering environment was simulated where a design team was able to work collectively, rather than as solely disjoint individual efforts. Finally, a successful animation of a Sandia part was demonstrated, and a computer video generated. This video is now accessible on a Sandia internal web server.
Date: August 1, 1997
Creator: Jortner, J. N.; Friesen, J. A. & Schwegel, J.
Object Type: Report
System: The UNT Digital Library
Advanced deformation process modeling (open access)

Advanced deformation process modeling

Progress was made in achieving a comprehensive and coherent description of material behavior in deformation processing. The materials included were metals, alloys, intermetallic compounds, arbitrary lattice structure, and metal matrix composites. Aspects of behavior modeled included kinetics of flow and strain hardening, as well as recrystallization and the various anisotropies of strength and compliance. Highlights include a new prediction of the limiting strength of materials at high temperature, a new understanding of the generation of new grain boundaries during forming operations, and a quantitatively verified computer simulation of texture development and the resulting behavioral anisotropies.
Date: August 1, 1997
Creator: Kocks, U. F.; Embury, J. D.; Beaudoin, A. J.; Dawson, P. R.; MacEwen, S. R. & Mecking, H. J.
Object Type: Report
System: The UNT Digital Library
Advanced micromechanisms in a multi-level polysilicon technology (open access)

Advanced micromechanisms in a multi-level polysilicon technology

Quad-level polysilicon surface micromachining technology, comprising three mechanical levels plus an electrical interconnect layer, is giving rise to a new generation of micro-electromechanical devices and assemblies. Enhanced components can not be produced through greater flexibility in fabrication and design. New levels of design complexity that include multi-level gears, single-attempt locks, and optical elements have recently been realized. Extensive utilization of the fourth layer of polysilicon differentiates these latter generation devices from their predecessors. This level of poly enables the fabrication of pin joints, linkage arms, hinges on moveable plates, and multi-level gear assemblies. The mechanical design aspects of these latest micromachines will be discussed with particular emphasis on a number of design aspects of these latest micromachines will be discussed with particular emphasis on a number of design modifications that improve the power, reliability, and smoothness of operation of the microengine. The microengine is the primary actuation mechanism that is being used to drive mirrors out of plane and rotate 1600-{mu}m diameter gears. Also discussed is the authors most advanced micromechanical system to date, a complex proof-of-concept batch-fabricated assembly that, upon transmitting the proper electrical code to a mechanical lock, permits the operation of a micro-optical shutter.
Date: August 1, 1997
Creator: Rodgers, M. S.; Sniegowski, J. J.; Miller, S. L.; Barron, C. C. & McWhorter, P. J.
Object Type: Article
System: The UNT Digital Library
Advanced oil recovery technologies for improved recovery from slope basin clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico. Annual report, September 25, 1995--September 24, 1996 (open access)

Advanced oil recovery technologies for improved recovery from slope basin clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico. Annual report, September 25, 1995--September 24, 1996

The basic driver for this project is the low recovery observed in Delaware reservoirs, such as the Nash Draw Pool (NDP). This low recovery is caused by low reservoir energy, less than optimum permeabilities and porosities, and inadequate reservoir characterization and reservoir management strategies which are typical of projects operated by independent producers. Rapid oil decline rates and high gas/oil ratios are typically observed in the first year of primary production. Based on the production characteristics that have been observed in similar Delaware fields, pressure maintenance is a likely requirement at the Nash Pool. Three basic constraints to producing the Nash Draw Brushy Canyon Reservoir are: (1) limited areal and interwell geologic knowledge, (2) lack of an engineering tool to evaluate the various producing strategies, and (3) limited surface access prohibiting development with conventional drilling. The limited surface access is caused by the proximity of underground potash mining and surface playa lakes. The objectives of this project are: (1) to demonstrate that a development drilling program and pressure maintenance program, based on advanced reservoir management methods, can significantly improve oil recovery compared with existing technology applications and (2) to transfer these advanced methodologies to oil and gas producers, especially in …
Date: August 1, 1997
Creator: Murphy, M. B.
Object Type: Report
System: The UNT Digital Library
Advanced photon source experience with vacuum chambers for insertion devices (open access)

Advanced photon source experience with vacuum chambers for insertion devices

During the last five years, a new approach to the design and fabrication of extruded aluminum vacuum chambers for insertion devices was developed at the Advanced Photon Source (APS). With this approach, three different versions of the vacuum chamber, with vertical apertures of 12 mm, 8 mm, and 5 mm, were manufactured and tested. Twenty chambers were installed into the APS vacuum system. All have operated with beam, and 16 have been coupled with insertion devices. Two different vacuum chambers with vertical apertures of 16 mm and 11 mm were developed for the BESSY-II storage ring and 3 of 16 mm chambers were manufactured.
Date: August 1, 1997
Creator: Hartog, P.D.; Grimmer, J.; Xu, S.; Trakhtenberg, E. & Wiemerslage, G.
Object Type: Article
System: The UNT Digital Library
The advanced photon source low-energy undulator test line (open access)

The advanced photon source low-energy undulator test line

There are a number of fully commissioned 3rd-generation synchrotron light sources in the world today. So far they have met the demanding requirements of the user community; however, there is always a desire to go beyond what is presently available or even desirable. The Advanced Photon Source (APS) Low-Energy Undulator Test Line (LEUTL) was conceived to address the advancement of synchrotron light sources. The LEUTL uses the existing APS linac and a low-emittance electron gun, and by means of measurements of the beam and generated light, will test new and innovative undulators and push the technology and physics of single-pass, coherent light sources. The design and status of the LEUTL will be described along with its immediate capabilities and those planned for the future.
Date: August 1, 1997
Creator: Milton, S. V.; Galayda, J. N. & Gluskin, E.
Object Type: Article
System: The UNT Digital Library
Advanced Sulfur Control Concepts for Hot Gas Desulfurization Technology. Quarterly Report, January 1--March 31, 1997 (open access)

Advanced Sulfur Control Concepts for Hot Gas Desulfurization Technology. Quarterly Report, January 1--March 31, 1997

Favorable results were achieved in the sulfidation of CeO{sub 2} by H{sub 2}S and the regeneration of Ce{sub 2}O{sub 2}S by SO{sub 2}. Successful removal of approximately 99% of the H{sub 2}S from the sulfidation gas to levels of about 100 ppmv (or lower), and the production of approximately 12% elemental sulfur (as S{sub 2}) in the regeneration product gas were highlights. Final effort in the preliminary phase included a ten-cycle test at standard sulfidation and regeneration conditions with little or no sorbent deterioration. In the initial test of the detailed experimental phase of the program, the authors investigated the effect of temperature on the regeneration reaction. Results of preliminary tests showed that the Ce{sub 2}O{sub 2}S-SO{sub 2} reaction did not occur at 350 C, and all subsequent regeneration tests were at 600 C where the reaction was rapid. Significant progress has been made on the process analysis effort during the quarter. Detailed process flow diagrams along with material and energy balance calculations for six design case studies were completed in the previous quarter. Two of the cases involved two-stage desulfurization with steam regeneration, three used two-stage desulfurization with SO{sub 2} regeneration, and the sixth was based on single-stage desulfurization …
Date: August 1, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Advances in 3D electromagnetic finite element modeling (open access)

Advances in 3D electromagnetic finite element modeling

Numerous advances in electromagnetic finite element analysis (FEA) have been made in recent years. The maturity of frequency domain and eigenmode calculations, and the growth of time domain applications is briefly reviewed. A high accuracy 3D electromagnetic finite element field solver employing quadratic hexahedral elements and quadratic mixed-order one-form basis functions will also be described. The solver is based on an object-oriented C++ class library. Test cases demonstrate that frequency errors less than 10 ppm can be achieved using modest workstations, and that the solutions have no contamination from spurious modes. The role of differential geometry and geometrical physics in finite element analysis is also discussed.
Date: August 1, 1997
Creator: Nelson, E.M.
Object Type: Article
System: The UNT Digital Library
AEM investigations of primary water SCC in nickel alloys (open access)

AEM investigations of primary water SCC in nickel alloys

The microstructure of nickel alloys, particularly the grain boundary composition and intergranular precipitates, plays an important role in high temperature primary water stress corrosion cracking (SCC) performance. Analytical electron microscopy (AEM) was used to examine SCC cracks in Alloys 600 and X-750 to investigate the role of grain boundary precipitates, dislocations and oxides in primary water SCC (PWSCC). Analysis of oxides by AEM and ESCA/Auger indicates that the crack tip oxides are different than the oxides formed on the outer surfaces. Comparison of heats with good and poor SCC resistance has identified metallurgical features that affect cracking. These AEM results show that the mechanism of PWSCC in nickel-base alloys does not involve void formation or blunting of the crack tip near intergranular carbides. The role of grain boundary composition, the interaction of cracks with carbides and other intergranular precipitates, and observations from AEM examinations ahead of the crack tip are discussed in relation to the mechanism of SCC.
Date: August 1, 1997
Creator: Fish, J. S.; Perry, D. J.; Lewis, N.; Thompson, C. D. & Yang, W. J. S.
Object Type: Report
System: The UNT Digital Library
Air cushion effect in the short-pulse initiation of explosives (open access)

Air cushion effect in the short-pulse initiation of explosives

When thin flyer plates are used to shock initiate high explosive (HE), any air present ahead of the flyer may cause a significant desensitization of the HE. The effect of the air in cushioning the impact of plastic flyers faced with metal films is analyzed here with MACRAME, a code which calculates wave interactions and traces wave propagation. The authors find that the second air shock into the HE has sufficient pressure to collapse the HE to crystal density or higher. Precompressed regions of HE do not react rapidly when the main impact pulse does arrive. Define y{sup *} as the depth where the major shock overtakes the precompression wave (for no air y{sup *} {r_arrow} 0). For various flyers and air combinations, the authors compare pressure profiles at y = y{sup *} + {epsilon}. The shock pressure profile associated with metal film impact may be greatly attenuated at the depth y{sup *}. Density profiles (p(t) at y) show that the shock heating for y > y{sup *} is greater than that for y < y{sup *}.
Date: August 1, 1997
Creator: Fritz, J. N. & Kennedy, J. E.
Object Type: Article
System: The UNT Digital Library