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Interim Report on the Development of an Air Pulser for Pulse Column Application (open access)

Interim Report on the Development of an Air Pulser for Pulse Column Application

The Idaho Chemical Processing Plant for several years has been studying various pulsing systems, used in extraction columns for processing irradiated nucIear fuel elements, in an effort to eliminate the mechanical difficuittes in present pulsing systems. An air puising system has been demonstrated, and a discussion is given of experimental work, pulser design, and plant operational experience with this system. It is concluded, from work completed thus far that air puising of extraction columns is a considerable improvement over other systems. (auth)
Date: September 22, 1961
Creator: Weech, M. E.; P'Pool, R. S. & MacQueen, D. K.
Object Type: Report
System: The UNT Digital Library
Injection septum magnets for the Loma Linda medical accelerator (open access)

Injection septum magnets for the Loma Linda medical accelerator

The injection beamline runs over the last magnet before a long straight section and is then displaced downward 55.88 cm to the accelerator beamline. The displacement is magnetic and the final deflection onto the synchrotron orbit is by an electric kicker. The first component, the reverse septum magnet, bends the injection beam 25)degree) downward. This is followed by the injection septum (20)degree) bend upward) and the final injection kicker (5)degree) bend upward). The septum magnets produce a peak field of 3.4 K gauss at a current of 28,000 amperes within a 0.1 msec long pulse. The electric kicker produces a field of 7.3 KV/cm with a pulse length of 0.0011 msec. The septum magnets are similar to each other in construction with a bending radium of 72.7 cm. The curvature is required to increase the effective aperture. Each magnet has a single-turn copper coil bonded to a stainless steel plate for reinforcement. This eliminates insulating material, which could be subject to radiation damage, at the septum. The stainless steel plate is welded to the magnet laminations. The current is confined to the septum by the insulation between the laminations, which are a standard core material. The total septum thickness with …
Date: September 22, 1987
Creator: Satti, J.A.
Object Type: Article
System: The UNT Digital Library
Background field coils for the High Field Test Facility (open access)

Background field coils for the High Field Test Facility

The High Field Test Facility (HFTF), presently under construction at LLNL, is a set of superconducting coils that will be used to test 1-m-o.d. coils of prototype conductors for fusion magnets in fields up to 12 T. The facility consists of two concentric sets of coils; the outer set is a stack of Nb-Ti solenoids, and the inner set is a pair of solenoids made of cryogenically-stabilized, multifilamentary Nb/sub 3/Sn superconductor, developed for use in mirror-fusion magnets. The HFTF system is designed to be parted along the midplane to allow high-field conductors, under development for Tokamak fusion machines, to be inserted and tested. The background field coils were wound pancake-fashion, with cold-welded joints at both the inner and outer diameters. Turn-to-turn insulation was fabricated at LLNL from epoxy-fiberglass strip. The coils were assembled and tested in our 2-m-diam cryostat to verify their operation.
Date: September 22, 1980
Creator: Zbasnik, J. P.; Cornish, D. N.; Scanlan, R. M.; Jewell, A. M.; Leber, R. L.; Rosdahl, A. R. et al.
Object Type: Article
System: The UNT Digital Library
Stability of space-charge neutralized beams (open access)

Stability of space-charge neutralized beams

Consideration is given to the stability of negative ion beams which are neutralized through ionization of a background gas. Two types of instabilities are examined. First, beam-plasma instabilities are analyzed with the dispersion relation showing that they are unimportant if the beam velocity is less than the electron thermal velocity. Second, results of a computer simulation on the flow of a cylindrical beam and the resulting background plasma show that when the background neutral gas density is less than or approximately equal to a critical density as instability occurs. This critical density is the density that would be needed to space-charge neutralize the beam if the positive ions were not retarded by the beam. An approximate dispersion relation indicates that the nature of the instability is a transverse positive-ion acoustic wave which couples to the beam.
Date: September 22, 1977
Creator: Turnbull, R. J. & Hooper, E. B. Jr.
Object Type: Article
System: The UNT Digital Library
Dispersive effects of transverse magnet displacements in rolled arc achromats (open access)

Dispersive effects of transverse magnet displacements in rolled arc achromats

The effect of transverse displacements of combined function magnets is investigated where the disperion in not matched due to roll. This dispersion function is perturbed by displacement of combined function magnets either singly or coherently. In the latter case the effect of a systematic (or DC) offset of magnets is examined. This type of error can occur due to systematics in the placement or the readout of Beam Position Monitors or equivalently by correcting the orbit of a beam of the wrong momentum with respect to the Arc magnet excitation. 5 refs., 18 figs.
Date: September 22, 1986
Creator: Fieguth, T.; Kheifets, S. & Murray, J. J.
Object Type: Report
System: The UNT Digital Library
Proposal to utilize fusion reactor energy sources for chemical process applications (open access)

Proposal to utilize fusion reactor energy sources for chemical process applications

We propose to study the utilization of high-temperature (approximately 2000-2500K) process heat from fusion reactors for large-scale chemical process applications. Of particular interest is the decomposition reaction, CO/sub 2/ ..-->.. CO + /sup 1///sub 2/O/sub 2/, which at 2500K should yield approximately 60 percent conversion to CO if O/sub 2/ is partially removed through an oxide membrane. Hydrogen can be derived from CO at lower temperatures by reacting CO with steam, and C can also be derived from CO by a disproportionation into C and CO/sub 2/ at approximately 1000K. These chemicals, CO, H/sub 2/, and C, form the basis for a multitude of non-electrical energy applications in the areas of transportation, industrial processes, and residential and commercial uses. In addition to the CO/sub 2/ decomposition process, we propose to explore a variety of ideas and evaluate them for scientific and economic merit. A follow-on research and development program will be proposed if the ideas prove promising.
Date: September 22, 1977
Creator: Krikorian, O. H.
Object Type: Report
System: The UNT Digital Library
Measurement of Coefficients of Reactivity. 0 EFPH. Core I, Seed 2. (T- 550132). Section 1 (open access)

Measurement of Coefficients of Reactivity. 0 EFPH. Core I, Seed 2. (T- 550132). Section 1

None
Date: September 22, 1960
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Cold-pressure-welded joints in large multifilamentary Nb--Ti superconductors (open access)

Cold-pressure-welded joints in large multifilamentary Nb--Ti superconductors

A number of mechanical and electrical measurements were made on joints in typical conductors for the proposed mirror fusion test facility (MFTF) and high field test facility (HFTF). For such measurements, a commercially available cold-pressure-welding machine was used. For joints in the MFTF conductor, which has a large proportion of superconductor, joint strength approached conductor strength. For the HFTF conductor, where the Cu-to-superconductor ratio is 4.33/1, the joint is stronger than the conductor. Electrically, the joints were not superconducting.. While the resistance is higher than might be achieved by other forms of joining, we feel that the cold-weld joint has the advantages of simplicity, speed, reliability, and reproducibility. This makes the method attractive for MFTF, where resistance losses will be small compared with the total 4 K refrigeration requirements.
Date: September 22, 1977
Creator: Cornish, D.N.; Deis, D.W. & Zbasnik, J.P.
Object Type: Article
System: The UNT Digital Library
Review of draft HTGR-SC/C design and technology development plans (open access)

Review of draft HTGR-SC/C design and technology development plans

GCRA has approached the initial review of the subject plans from the vantage of Utility/User interests in an HTGR-SC/C Lead Project as characterized in the HTGR-SC/C Lead Project Plan. At their current stage of development, the plans are considered to represent the early views of General Atomic Company, acting as a potential NSSS vendor, on the effort necessary to design and license an HTGR-SC/C plant. As such, these plans embody GA's perception of the level of technical development and demonstration needed to support the cost and risk sharing assumptions in the Lead Project Plan. These plans and the plant design which they address will be subjected to a more formal review by other vendor and Utility interests in the course of establishing the Project Decision Package scheduled for June 1982. The culmination of these review activities will be the adoption of this information by all participants as the HTGR-SC/C Program Baseline.
Date: September 22, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Vectorizing and machine-spanning techniques (open access)

Vectorizing and machine-spanning techniques

Techniques for vectorizing complex logic are shown using a decoupled sliding-surface calculation that is part of a two-dimensional Lagrangian simulation model. The same source coding can be run on many vector, parallel, and multiprocessor computers with very little or no alteration. The vectorizing techniques have been used for a wide range of problems.
Date: September 22, 1983
Creator: Giroux, E D
Object Type: Article
System: The UNT Digital Library
TEBASCO user's guide (open access)

TEBASCO user's guide

TEBASCO is a Tandem mirror Equilibrium and BAllooning Stability COde. TEBASCO allows you to compute tandem-mirror MHD equilibria and to analyze both the flute-averaged and ballooning-mode stability of these equilibria. This stability analysis is directed toward the computation of marginal stability boundaries. Users of TEBASCO require a binary output file from the EFFI code which describes the vacuum magnetic field. In making this EFFI file the user will have defined a system of units for lengths (e.g., meters) and magnetic field (e.g., Tesla). In TEBASCO, all magnetic field strengths are normalized to the vacuum center-cell midplane value, and times are defined in units of the time for an Alfven wave in this field to transit one EFFI unit of length.
Date: September 22, 1983
Creator: Pearlstein, L. D.; Kaiser, T. B.; LoDestro, L.; Maron, N.; Nevins, W. M. & Willmann, P. A.
Object Type: Report
System: The UNT Digital Library
Stochastic Acceleration by a Single Wave in a Magnetized Plasma (open access)

Stochastic Acceleration by a Single Wave in a Magnetized Plasma

A particularly simple problem exhibiting stochasticity is the motion of a charged particle in a uniform magnetic field and a single wave. Detailed studies of this wave-particle interaction show the following features. An electrostatic wave propagating obliquely to the magnetic field causes stochastic motion if the wave amplitude exceeds a certain threshold. The overlap of cyclotron resonances then destroys a constant of the motion, allowing strong particle acceleration. A wave of large enough amplitude would thus suffer severe damping and lead to rapid heating of a particle distribution. The stochastic motion resembles a diffusion process even though the wave spectrum contains only a single wave. The motion of ions in a nonuniform magnetic field and a single electrostatic wave is treated in our study of a possible saturation mechanism of the dissipative trapped-ion instability in a tokamak. A theory involving the overlap of bounce resonances predicts the main features found in the numerical integration of the equations of motion. Ions in a layer near the trapped-circulating boundary move stochastically. This motion leads to nonlinear stabilization mechanisms which are described qualitatively.
Date: September 22, 1977
Creator: Smith, R.
Object Type: Report
System: The UNT Digital Library
Characterization of Tank 17 Residual Waste (open access)

Characterization of Tank 17 Residual Waste

Plans are to close Tank 17, a type IV waste tank in the F-area Tank Farm, by filling it with pumpable backfills. Most of the waste was removed from the tank in the late 1980s, and the remainder of the waste was removed in a short spray washing campaign that began on 11 April 1997. More details on the planned closure can be found in the Closure Plan for the High-Level Waste (HLW) Tanks and the specific closure module for Tank 17. To show that closure of the tank is environmentally sound, a performance evaluation has been performed for Tank 17. The performance evaluation projected the concentration of contaminants at various locations and times after closure. This report documents the basis for the inventories of contaminants that were used in the Tank 17 performance evaluation.
Date: September 22, 1997
Creator: D'Entremont, P. & Thomas Caldwell, T.
Object Type: Report
System: The UNT Digital Library
LINAC DESIGN FOR AN ARRAY OF SOFT X-RAY FREE ELECTRON LASERS (open access)

LINAC DESIGN FOR AN ARRAY OF SOFT X-RAY FREE ELECTRON LASERS

The design of the linac delivering electron bunches into ten independent soft x-ray free electron lasers (FELs) producing light at 1 nm and longer wavelengths is presented. The bunch repetition rate in the linac is 1 MHz and 100 kHz in each of ten FEL beam lines. Various issues regarding machine layout and lattice, bunch compression, collimation, and the beam switch yard are discussed. Particular attention is given to collective effects. A demanding goal is to preserve both a low beam slice emittance and low slice energy spread during acceleration, bunch compression and distribution of the electron bunches into the array of FEL beamlines. Detailed studies of the effect of the electron beam microbunching caused by longitudinal space-charge forces and coherent synchrotron radiation (CSR) have been carried out and their results are presented.
Date: September 22, 2008
Creator: Zholents, Alexander A.; Kur, E.; Penn, G.; Qiang, Ji; Venturini, M. & Wells, R. P.
Object Type: Article
System: The UNT Digital Library
Model-Independent Jets plus Missing Energy Searches (open access)

Model-Independent Jets plus Missing Energy Searches

We present a proposal for performing model-independent jets plus missing energy searches. Currently, these searches are optimized for mSUGRA and are consequently not sensitive to all kinematically-accessible regions of parameter space. We show that the reach of these searches can be broadened by setting limits on the differential cross section as a function of the total visible energy and the missing energy. These measurements only require knowledge of the relevant Standard Model backgrounds and can be subsequently used to limit any theoretical model of new physics. We apply this approach to an example where gluinos are pair-produced and decay to the LSP through a single-step cascade, and show how sensitivity to different gluino masses is altered by the presence of the decay chain. The analysis is closely based upon the current searches done at the Tevatron and our proposal requires only small modifications to the existing techniques. We find that within the MSSM, the gluino can be as light as 125 GeV. The same techniques are applicable to jets and missing energy searches at the Large Hadron Collider.
Date: September 22, 2008
Creator: Alwall, Johan; Le, My-Phuong; Lisanti, Mariangela & Wacker, Jay G.
Object Type: Article
System: The UNT Digital Library
805 MHz Beta = 0.47 Elliptical Accelerating Structure R & D (open access)

805 MHz Beta = 0.47 Elliptical Accelerating Structure R & D

A 6-cell 805 MHz superconducting cavity for acceleration in the velocity range of about 0.4 to 0.53 times the speed of light was designed. After single-cell prototyping, three 6-cell niobium cavities were fabricated. In vertical RF tests of the 6-cell cavities, the measured quality factors (Q{sub 0}) were between 7 {center_dot} 10{sup 9} and 1.4 {center_dot} 10{sup 10} at the design field (accelerating gradient of 8 to 10 MV/m). A rectangular cryomodule was designed to house 4 cavities per cryomodule. The 4-cavity cryomodule could be used for acceleration of ions in a linear accelerator, with focusing elements between the cryomodules. A prototype cryomodule was fabricated to test 2 cavities under realistic operating conditions. Two of the 6-cell cavities were equipped with helium tanks, tuners, and input coupler and installed into the cryomodule. The prototype cryomodule was used to verify alignment, electromagnetic performance, frequency tuning, cryogenic performance, low-level RF control, and control of microphonics.
Date: September 22, 2008
Creator: Bricker, S.; Compton, C.; Hartung, W.; Johnson, M.; Marti, F.; Popierlarski, J. et al.
Object Type: Report
System: The UNT Digital Library
Modeling Growth of Au-Cu Nanocrystalliine Coatings (open access)

Modeling Growth of Au-Cu Nanocrystalliine Coatings

The electrodeposition process parameters of current density, pulse duration, and cell potential affect both the structure and composition of the foils. The mechanism for nucleation and growth as determined from current transients yield relationships for nucleus density and nucleation rate. To develop an understanding of the role of the process parameters on grain size--as a design structural parameter to control strength, for example, a formulation is presented to model the affects of the deposition energetics on grain size and morphology. An activation energy for the deposition process is modeled that reveals different growth mechanisms, wherein nucleation and diffusion effects are each dominant as dependent upon pulse duration. A diffusion coefficient common for each of the pulsed growth modes demarcates an observed transition in growth from smooth to rough surfaces. Empirical relationships are developed that relate the parameters of the deposition process to the morphology and grain size at the nanoscale. Regimes for nanocrystalline growth include a short and long pulse mode, each with distinct activation energies. The long pulse has the additional contribution of bulk-like diffusion whereas the short pulse is limited to surface diffusion and nucleation. For either pulse condition, a transition from a rough (or nodular) growth to …
Date: September 22, 2005
Creator: Jankowski, Alan Frederic
Object Type: Article
System: The UNT Digital Library
Silicon-Germanium Films Deposited by Low Frequency PE CVD: Effect of H2 and Ar Dilution (open access)

Silicon-Germanium Films Deposited by Low Frequency PE CVD: Effect of H2 and Ar Dilution

We have studied structure and electrical properties of Si{sub 1-Y}Ge{sub Y}:H films deposited by low frequency PE CVD over the entire composition range from Y=0 to Y=1. The deposition rate of the films and their structural and electrical properties were measured for various ratios of the germane/silane feed gases and with and without dilution by Ar and by H{sub 2}. Structure and composition was studied by Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS) and Fourier transform infrared (FTIR) spectroscopy. Surface morphology was characterized by atomic force microscopy (AFM). We found: (1) The deposition rate increased with Y maximizing at Y=1 without dilution. (2) The relative rate of Ge and Si incorporation is affected by dilution. (3) Hydrogen preferentially bonds to silicon. (4) Hydrogen content decreases for increasing Y. In addition, optical measurements showed that as Y goes for 0 to 1, the Fermi level moves from mid gap to the conduction band edge, i.e. the films become more n-type. No correlation was found between the pre-exponential and the activation energy of conductivity. The behavior of the conductivity {gamma}-factor suggests a local minimum in the density of states at E {approx} 0.33 eV for the films grown with or …
Date: September 22, 2005
Creator: Kosarev, A; Torres, A; Hernandez, Y; Ambrosio, R; Zuniga, C; Felter, T E et al.
Object Type: Article
System: The UNT Digital Library
Mu B-Driven Electroweak Symmetry Breaking (open access)

Mu B-Driven Electroweak Symmetry Breaking

None
Date: September 22, 2005
Creator: Nomura, Yasunori; Poland, David & Tweedie, Brock
Object Type: Article
System: The UNT Digital Library
ORGANIC GEOCHEMICAL STUDIES. I. MOLECULAR CRITERIA FOR HYDROCARBONGENESIS (open access)

ORGANIC GEOCHEMICAL STUDIES. I. MOLECULAR CRITERIA FOR HYDROCARBONGENESIS

In recent years the search for life-forms at the earliest periods of geological time has been continued not only at the morphological level but also at the molecular level. This has been possible as a result of the increase in the biochemical knowledge and with the advent of analytical techniques that are capable of describing the intimate molecular architecture of individual molecules in acute detail. The fundamental premises upon which this organic geochemical approach rest are the following: that certain molecules, possessing a characteristic structural skeleton, show a reasonable stability to degradation over long periods of geological time; that their structural specificity can be understood in terms of known biosynthetic sequences; and that their formation by any non-biological means is of negligible probability. In this manuscript it is proposed to critically re-examine these premises and to establish criteria whereby one can differentiate molecules derived from biological systems from those that have their origin in non-biological processes. The importance of establishing such criteria lies in the significance these criteria have in determining whether life exists, or has existed, on other planets. Within the very near future it may be possible to provide an initial answer to this question when the first …
Date: September 22, 1967
Creator: McCarthy, Eugene D. & Calvin, Kevin
Object Type: Article
System: The UNT Digital Library
A comparison of model short-range forecasts and the ARM Microbase data (open access)

A comparison of model short-range forecasts and the ARM Microbase data

For the fourth quarter ARM metric we will make use of new liquid water data that has become available, and called the 'Microbase' value added product (referred to as OBS, within the text) at three sites: the North Slope of Alaska (NSA), Tropical West Pacific (TWP) and the Southern Great Plains (SGP) and compare these observations to model forecast data. Two time periods will be analyzed March 2000 for the SGP and October 2004 for both TWP and NSA. The Microbase data have been averaged to 35 pressure levels (e.g., from 1000hPa to 100hPa at 25hPa increments) and time averaged to 3hourly data for direct comparison to our model output.
Date: September 22, 2006
Creator: Hnilo, J J
Object Type: Report
System: The UNT Digital Library
Final Technical Report Steam Cycle Washer for Unbleached Pulp (open access)

Final Technical Report Steam Cycle Washer for Unbleached Pulp

Project Abstract for “Steam Cycle Washer for Unbleached Pulp” When completed, the patented SC Washer will provide an innovative, energy efficient demonstration project to wash unbleached pulp using a pressure vessel charged with steam. The Port Townsend Paper Corporation’s pulp mill in Port Townsend, WA was initially selected as the host site for conducting the demonstration of the SCW. Due to 2006 and 2007 delays in the project caused by issues with 21st Century Pulp & Paper, the developer of the SCW, and the 2007 bankruptcy proceedings and subsequent restructuring at Port Townsend Paper, the mill can no longer serve as a host site. An alternate host site is now being sought to complete the commercial demonstration of the Steam Cycle Washer for Unbleached Pulp. Additionally, estimated costs to complete the project have more than doubled since the initial estimates for the project were completed in 2002. Additional grant funding from DOE was sought and in July, 2008 the additional DOE funds were procured under a new DOE award, DE-PS36-08GO98014 issued to INL. Once the new host site is secured the completion of the project will begin under the management of INL. Future progress reports and milestone tracking will be …
Date: September 22, 2008
Creator: Starkey, Yvonne; Salminen, Reijo & Karlsnes, Andy
Object Type: Report
System: The UNT Digital Library
Enhancement of T1 and T2 relaxation by paramagnetic silica-coated nanocrystals (open access)

Enhancement of T1 and T2 relaxation by paramagnetic silica-coated nanocrystals

None
Date: September 22, 2006
Creator: Gerion, D; Herberg, J; Gjersing, E; Ramon, E; Maxwell, R; Gray, J W et al.
Object Type: Article
System: The UNT Digital Library
2007 GRC on Cellulases and Cellulosomes (July 29-August 3, 2007) (open access)

2007 GRC on Cellulases and Cellulosomes (July 29-August 3, 2007)

Cellulose, a key component of the plant cell wall, comprises the most abundant source of organic carbon on the planet and its microbial degradation is of considerable biological and industrial importance. Indeed, the microbial degradation of cellulose and other plant structural polysaccharides is critical to the maintenance of the carbon cycle in terrestrial and marine microbial ecosystems, host invasion by several phytopathogens, and herbivore nutrition. While the enzymes that attack cellulose are already widely used in several biotechnology-based industries, the major future application of these biocatalysts is the conversion of plant biomass into bio-ethanol and other forms of energy. In that context, the 2007 Conference will present the latest breakthroughs in our understanding of the enzymology, structural biology and (meta)genomics underpinning the conversion of plant structural polysaccharides into fermentable sugars, both in natural and engineered processes. There is also an increased emphasis on the roles of other carbohydrate active enzymes in plant biomass conversion. The themes for the scientific sessions include: (1) crystallographic and biochemical analyses of enzyme structure and function; (2) molecular mechanisms underpinning enzyme catalysis, processivity and specificity; (3) functional and comparative analyses of carbohydrate binding modules and enzyme-substrate interactions; (4) directed evolution for the development of catalytically …
Date: September 22, 2008
Creator: Gray, Mark Morrison Nancy Ryan
Object Type: Article
System: The UNT Digital Library