States

Comments on septa and other small production angle magnets (open access)

Comments on septa and other small production angle magnets

A discussion is given of possible septum magnet parameters for small production angle experiments in the ISABELLE storage rings. Superconducting septa and torroidal septa are also considered. (PMA)
Date: August 25, 1977
Creator: Allinger, J.; Danby, G. & Jackson, J.
Object Type: Article
System: The UNT Digital Library
Fire protection countermeasures for containment ventilation systems (open access)

Fire protection countermeasures for containment ventilation systems

The goal of this project is to find countermeasures to protect High Efficiency Particulate Air (HEPA) filters, in exit ventilation ducts, from the heat and smoke generated by fire. Initially, methods were developed to cool fire-heated air by fine water spray upstream of the filters. It was recognized that smoke aerosol exposure to HEPA filters could also cause disruption of the containment system. Through testing and analysis, several methods to partially mitigate the smoke exposure to the HEPA filters were identified. A continuous, movable, high-efficiency prefilter using modified commercial equipment was designed. The technique is capable of protecting HEPA filters over the total time duration of the test fires. The reason for success involved the modification of the prefiltration media. Commercially available filter media has particle sorption efficiency that is inversely proportional to media strength. To achieve properties of both efficiency and strength, rolling filter media were laminated with the desired properties. The approach was Edisonian, but truncation in short order to a combination of prefilters was effective. The application of this technique was qualified, since it is of use only to protect HEPA filters from fire-generated smoke aerosols. It is not believed that this technique is cost effective in …
Date: August 25, 1980
Creator: Alvares, N.; Beason, D.; Bergman, V.; Creighton, J.; Ford, H. & Lipska, A.
Object Type: Report
System: The UNT Digital Library
Spectrographic Determination of Impurities in Hafnium (open access)

Spectrographic Determination of Impurities in Hafnium

A spectrographic method using d-c arc excitation in a controlled atmosphere was developed to analyze for seven impurity elements in radioactive hafnium samples. Analysis requires as little as 35 mg of hafnium oxide. (auth)
Date: August 25, 1961
Creator: Ginther, B. E. & Wheeler, G. V.
Object Type: Report
System: The UNT Digital Library
Viewgraph notes: geologic aspects of terminal storage of radioactive wastes (open access)

Viewgraph notes: geologic aspects of terminal storage of radioactive wastes

This document contains copies of viewgraphs discussed in a presentation made at the Fifth Annual Power Conference, August 29 to September 2, 1977. No text. 19 figures, 11 references.
Date: August 25, 1977
Creator: Lomenick, T.F.
Object Type: Article
System: The UNT Digital Library
Hybrid simulations of quasineutral phenomena in magnetized plasma (open access)

Hybrid simulations of quasineutral phenomena in magnetized plasma

A new class of numerical algorithms for computer simulation of low frequency electromagnetic and electrostatic phenomena in magnetized plasma is presented. Maxwell's equations are solved in the limits of quasineutrality and negligible transverse displacement current (Darwin's model). Electrons are modeled as a fluid with polarization effects ignored. Ions are described as particles. A novel feature of these algorithms is the use of the electron fluid equation of motion to determine the electric field, which renders these numerical schemes remarkably simple and direct. The simulation plasma is either periodic or bounded by particle reflecting conducting walls. Both fully nonlinear codes with spatial grids and linearized gridless codes have been implemented.
Date: August 25, 1977
Creator: Byers, J.A.; Cohen, B.I.; Condit, W.C. & Hanson, J.D.
Object Type: Report
System: The UNT Digital Library
10-MWe pilot-plant-receiver panel test requirements document solar thermal test facility (open access)

10-MWe pilot-plant-receiver panel test requirements document solar thermal test facility

Testing plans for a full-scale test receiver panel and supporting hardware which essentially duplicate both physically and functionally, the design planned for the Barstow Solar Pilot Plant are presented. Testing is to include operation during normal start and shutdown, intermittent cloud conditions, and emergencies to determine the panel's transient and steady state operating characteristics and performance under conditions equal to or exceeding those expected in the pilot plant. The effects of variations of input and output conditions on receiver operation are also to be investigated. Test hardware are described, including the pilot plant receiver, the test receiver assembly, receiver panel, flow control, electrical control and instrumentation, and structural assembly. Requirements for the Solar Thermal Test Facility for the tests are given. The safety of the system is briefly discussed, and procedures are described for assembly, installation, checkout, normal and abnormal operations, maintenance, removal and disposition. Also briefly discussed are quality assurance, contract responsibilities, and test documentation. (LEW)
Date: August 25, 1978
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Hybrid charged-particle guide for studying (n, charged particle) reactions (open access)

Hybrid charged-particle guide for studying (n, charged particle) reactions

Charged-particle transport systems consisting of magnetic quadrupole lenses have been employed in recent years in the study of (n, charged particle) reactions. We have completed a new transport system that is based both on magnetic lenses as well as electrostatic fields. The magnetic focusing of this charged-particle guide is provided by six magnetic quadrupole lenses arranged in a CDCCDC sequence (in the vertical plane). The electrostatic field is produced by a wire at high voltage which stretches the length of the guide and is physically at the center of the magnetic axis. The magnetic lenses are used for charged particles above 5 MeV; the electrostatic guide is used for lower energies. This hybrid system possesses the excellent focusing and background rejection properties of other magnetic systems. For low energy charged-particles, the electrostatic transport avoids the narrow band-passes in charged-particle energy which are a problem with purely magnetic transport systems. This system is installed at the LLNL Cyclograaff facility for the study of (n, charged particle) reactions at neutron energies up to 35 MeV.
Date: August 25, 1982
Creator: Haight, R. C.; White, R. M. & Zinkle, S. J.
Object Type: Article
System: The UNT Digital Library
Supernovae, compact stars and nuclear physics (open access)

Supernovae, compact stars and nuclear physics

We briefly review the current understanding of supernova. We investigate the implications of rapid rotation corresponding to the frequency of the new pulsar reported in the supernovae remnant SN1987A. It places very stringent conditions on the equation of state if the star is assumed to be bound by gravity alone. We find that the central energy density of the star must be greater than 12 times that of nuclear density to be stable against the most optimistic estimate of general relativistic instabilities. This is too high for the matter to plausibly consist of individual hadrons. We conclude that the newly discovered pulsar, if its half-millisecond signals are attributable to rotation, cannot be a neutron star. We show that it can be a strange quark star, and that the entire family of strange stars can sustain high rotation under appropriate conditions. We discuss the conversion of a neutron star to strange star, the possible existence of a crust of heavy ions held in suspension by centrifugal and electric forces, the cooling and other features. 39 refs., 8 figs., 2 tabs.
Date: August 25, 1989
Creator: Glendenning, N.K.
Object Type: Article
System: The UNT Digital Library
An Evaluation of the Krieger-Nelkin Method From Calculations of Slow Neutron Scattering by CH$sub 4$ (open access)

An Evaluation of the Krieger-Nelkin Method From Calculations of Slow Neutron Scattering by CH$sub 4$

None
Date: August 25, 1961
Creator: McMurry, H. L.; Griffing, G. W.; Hestir, W. A. & Gannon, L. J.
Object Type: Report
System: The UNT Digital Library
Mirror theory applied to toroidal systems (open access)

Mirror theory applied to toroidal systems

Central features of a mirror plasma are strong departures from Maxwellian distribution functions, ambipolar potentials and densities which vary along a field line, and losses, and the mirror field itself. To examine these features, mirror theorists have developed analytical and numerical techniques to solve the Fokker-Planck equation, evaluate the potentials consistent with the resulting distribution functions, and assess the microstability of these distributions. Various combinations of mirror-plasma fetures are present and important in toroidal plasmas as well, particularly in the edge region and in plasmas with strong r.f. heating. In this paper we survey problems in toroidal plasmas where mirror theory and computational techniques are applicable, and discuss in more detail three specific examples: calculation of the toroidal generalization of the Spitzer-Haerm distribution function (from which trapped-particle effects on current drive can be calculated), evaluation of the nonuniform potential and density set up by pulsed electron-cyclotron heating, and calculation of steady-state distribution functions in the presence of strong r.f. heating and collisions. 37 refs., 3 figs.
Date: August 25, 1987
Creator: Cohen, R.H.
Object Type: Article
System: The UNT Digital Library
Measured resolutions of the Arc and Linac BPM systems (open access)

Measured resolutions of the Arc and Linac BPM systems

The 6'' long final focus beam position monitors (short FF BPM's are longer, thus deliver more signal after a 15 nanosecond filter, than either the Linac or Arc monitors. The purpose of this note is to compare the resolution of the Arc vs Linac electronics when applied to a short FF 2'' diameter BPM. A method of calibrating the Arc modules is also tested and briefly discussed. The range of each DAC setting to minimize digitization error is also calculated.
Date: August 25, 1986
Creator: Pappas, D. & Tentindo, S.
Object Type: Report
System: The UNT Digital Library
Rolling Contact Fatigue of Ceramics (open access)

Rolling Contact Fatigue of Ceramics

None
Date: August 25, 2006
Creator: Wereszczak, A. A.; Wang, W.; Wang, Y.; Hadfield, M.; Kanematsu, W.; Kirkland, T. P. et al.
Object Type: Report
System: The UNT Digital Library
Primary Quantum Conversion in Photosynthesis (open access)

Primary Quantum Conversion in Photosynthesis

None
Date: August 25, 1962
Creator: Calvin, Melvin & Androes, G. M.
Object Type: Article
System: The UNT Digital Library
Electron-Cloud Build-Up Simulations for the FNAL Main Injector (open access)

Electron-Cloud Build-Up Simulations for the FNAL Main Injector

We present a summary on ongoing simulation results for the electron-cloud (EC) buildup in the context of the proposed FNAL Main Injector (MI) intensity upgrade effort [1]. Most of the results presented here are for the field-free region at the location of the retarding field analyzer (RFA) electron detector [2-4]. The primary input variable we exercise is the peak secondary electron yield (SEY) {delta}{sub max}, which we let vary in the range 1.2 {le} {delta}{sub max} {le} 1.7. By combining our simulated results for the electron flux at the vacuum chamber wall with the corresponding RFA measurements we infer that 1.25 {approx}< {delta}{sub max} {approx}< 1.35 at this location. From this piece of information we estimate features of the EC distribution for various fill patterns, including the average electron number density n{sub e}. We then compare the behavior of the EC for a hypothetical RF frequency f{sub RF} = 212 MHz with the current 53 MHz for a given total beam population N{sub tot}. The density n{sub e} goes through a clear threshold as a function of N{sub tot} in a field-free region. As expected, the higher frequency leads to a weaker EC effect: the threshold in N{sub tot} is …
Date: August 25, 2008
Creator: Furman, Miguel .A.
Object Type: Article
System: The UNT Digital Library
Method of making multilayered titanium ceramic composites (open access)

Method of making multilayered titanium ceramic composites

A method making a titanium ceramic composite involves forming a hot pressed powder body having a microstructure comprising at least one titanium metal or alloy layer and at least one ceramic particulate reinforced titanium metal or alloy layer and hot forging the hot pressed body follwed by hot rolling to substantially reduce a thickness dimension and substantially increase a lateral dimension thereof to form a composite plate or sheet that retains in the microstructure at least one titanium based layer and at least one ceramic reinforced titanium based layer in the thickness direction of the composite plate or sheet.
Date: August 25, 1998
Creator: Fisher, George T., II; Hansen; Jeffrey, S.; Oden; Laurance, L.; Turner et al.
Object Type: Patent
System: The UNT Digital Library
Remaining Sites Verification Package for the 100-F-33, 146-F Aquatic Biology Fish Ponds, Waste Site Reclassification Form 2006-021 (open access)

Remaining Sites Verification Package for the 100-F-33, 146-F Aquatic Biology Fish Ponds, Waste Site Reclassification Form 2006-021

The 100-F-33, 146-F Aquatice Biology Fish Ponds waste site was an area with six small rectangular ponds and one large circular pond used to conduct tests on fish using various mixtures of river and reactor effluent water. The current site conditions achieve the remedial action objectives specified in the Remaining Sites ROD. The results of verification and applicable confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: August 25, 2006
Creator: Dittmer, L. M.
Object Type: Report
System: The UNT Digital Library
Verification (mostly) for High Energy Density Radiation Transport: 5 Case Studies (open access)

Verification (mostly) for High Energy Density Radiation Transport: 5 Case Studies

None
Date: August 25, 2006
Creator: Castor, J I
Object Type: Article
System: The UNT Digital Library
A phylogenomic gene cluster resource: The phylogeneticallyinferred groups (PhlGs) database (open access)

A phylogenomic gene cluster resource: The phylogeneticallyinferred groups (PhlGs) database

We present here the PhIGs database, a phylogenomic resource for sequenced genomes. Although many methods exist for clustering gene families, very few attempt to create truly orthologous clusters sharing descent from a single ancestral gene across a range of evolutionary depths. Although these non-phylogenetic gene family clusters have been used broadly for gene annotation, errors are known to be introduced by the artifactual association of slowly evolving paralogs and lack of annotation for those more rapidly evolving. A full phylogenetic framework is necessary for accurate inference of function and for many studies that address pattern and mechanism of the evolution of the genome. The automated generation of evolutionary gene clusters, creation of gene trees, determination of orthology and paralogy relationships, and the correlation of this information with gene annotations, expression information, and genomic context is an important resource to the scientific community.
Date: August 25, 2005
Creator: Dehal, Paramvir S. & Boore, Jeffrey L.
Object Type: Article
System: The UNT Digital Library
IBS suppression lattice in RHIC: theory and experimental verification (open access)

IBS suppression lattice in RHIC: theory and experimental verification

Intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for Relativistic Heavy Ion Collider (RHIC) operation with heavy ions. Over the last few years the process of IBS was carefully studied in RHIC with dedicated IBS measurements and their comparison with the theoretical models. A new lattice was recently designed and implemented in RHIC to suppress transverse IBS growth, which lowered the average arc dispersion by about 20% [1]. This lattice became operational during RHIC Run-8. We review the IBS suppression mechanism, IBS measurements before and after the lattice change, and comparisons with predictions.
Date: August 25, 2008
Creator: Fedotov, A. V.; Bai, M.; Bruno, D.; Cameron, P.; Connolly, R.; Cupolo, J. et al.
Object Type: Article
System: The UNT Digital Library
Interface reconstruction and sub-zone physics models (open access)

Interface reconstruction and sub-zone physics models

None
Date: August 25, 2005
Creator: Bailey, D S; Brown, S A & Zimmerman, G B
Object Type: Article
System: The UNT Digital Library
Test Results of a Nb3Sn Wind/React 'Stress-Managed' BlockDipole (open access)

Test Results of a Nb3Sn Wind/React 'Stress-Managed' BlockDipole

A second phase of a highfield dipole technology developmenthas been tested. A Nb3Sn block-coil model dipole was fabricated, usingmagnetic mirror geometry and wind/react coil technology. The primaryobjective of this phase was to make a first experimental test of thestress-management strategy pioneered at Texas A&M. In this strategy ahigh-strength support matrix is integrated with the windings to interceptLorentz stress from the inner winding so that it does not accumulate inthe outer winding. The magnet attained a field that was consistent withshort sample limit on the first quench; there was no training. Thedecoupling of Lorentz stress between inner and outer windings wasvalidated. In ramp rate studies the magnet exhibited a remarkablerobustness in rapid ramping operation. It reached 85 percent of shortsample(ss) current even while ramping 2-3 T/s. This robustness isattributed to the orientation of the Rutherford cables parallel to thefield in the windings, instead of the transverse orientation thatcharacterizes common dipole designs. Test results are presented and thenext development phase plans are discussed.
Date: August 25, 2006
Creator: McInturff, A.; Bish, P.; Blackburn, R.; Diaczenko, N.; Elliott,T.; Hafalia Jr., R. et al.
Object Type: Article
System: The UNT Digital Library
Electron-Cloud Build-Up Simulations for the FNAL Main Injector (open access)

Electron-Cloud Build-Up Simulations for the FNAL Main Injector

None
Date: August 25, 2008
Creator: Furman, Miguel A.
Object Type: Article
System: The UNT Digital Library
Beam dynamics limits for low-energy RHIC operation (open access)

Beam dynamics limits for low-energy RHIC operation

There is a strong interest in low-energy RHIC operations in the single-beam total energy range of 2.5-25 GeV/nucleon [1-3]. Collisions in this energy range, much of which is below nominal RHIC injection energy, will help to answer one of the key questions in the field of QCD about the existence and location of a critical point on the QCD phase diagram [4]. There have been several short test runs during 2006-2008 RHIC operations to evaluate RHIC operational challenges at these low energies [5]. Beam lifetimes observed during the test runs were limited by machine nonlinearities. This performance limit can be improved with sufficient machine tuning. The next luminosity limitation comes from transverse and longitudinal Intra-beam Scattering (IBS), and ultimately from the space-charge limit. Here we summarize dynamic effects limiting beam lifetime and possible improvement with electron cooling.
Date: August 25, 2008
Creator: Fedotov, A. V.; Ben-Zvi, Ilan; Chang, X.; Kayran, D.; Litvinenko, V. N.; Pozdeyev, E. et al.
Object Type: Article
System: The UNT Digital Library
GEOCHEMICAL CONTROLS ON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS (open access)

GEOCHEMICAL CONTROLS ON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS

Proton nuclear magnetic resonance (NMR) is used in the Earth Sciences as a means of obtaining information about the molecular-scale environment of fluids in porous geological materials. Laboratory experiments were conducted to advance our fundamental understanding of the link between the NMR response and the geochemical properties of geological materials. In the first part of this research project, we studied the impact of both the surface-area-to-volume ratio (S/V) of the pore space and the surface relaxivity on the NMR response of fluids in sand-clay mixtures. This study highlighted the way in which these two parameters control our ability to use NMR measurements to detect and quantify fluid saturation in multiphase saturated systems. The second part of the project was designed to explore the way in which the mineralogic form of iron, as opposed to simply the concentration of iron, affects the surface relaxation rate and, more generally, the NMR response of porous materials. We found that the magnitude of the surface relaxation rate was different for the various iron-oxide minerals because of changes in both the surface-area-to-volume ratio of the pore space, and the surface relaxivity. Of particular significance from this study was the finding of an anomalously large surface …
Date: August 25, 2008
Creator: Knight, Rosemary
Object Type: Report
System: The UNT Digital Library