States

Models and theory for precompound angular distributions (open access)

Models and theory for precompound angular distributions

We compare angular distributions calculated by folding nucleon- nucleon scattering kernels, using the theory of Feshbach, Kerman and Koonin, and the systematics of Kalbach, with a wide range of data. The data range from (n,xn) at 14 MeV incident energy to (p,xn) at 160 MeV incident energy. The FKK theory works well with one adjustable parameter, the depth of the nucleon-nucleon interaction potential. The systematics work well when normalized to the hybrid model single differential cross section prediction. The nucleon- nucleon scattering approach seems inadequate. 9 refs., 10 figs.
Date: June 6, 1990
Creator: Blann, M.; Pohl, B. A.; Remington, B. A.; Scobel, W.; Trabandt, M.; Byrd, R. C. et al.
Object Type: Article
System: The UNT Digital Library
Ecology for a changing earth. Final report (open access)

Ecology for a changing earth. Final report

To forecast the ecological impact of global change, research initiatives are needed on the explicit role of humans in ecological systems, and on how ecological processes functioning at different spatial and temporal scales are coupled. Furthermore, to synthesize the results of ecological research for Congress, policymakers, and the general public, a new agency, called the United States Ecological Survey (USES) is urgently required. Also, a national commitment to environmental health, as exemplified by establishing a National Institutes of the Environment (NIE), should be a goal.
Date: February 6, 1990
Creator: Brown, J. H. & Roughgarden, J.
Object Type: Report
System: The UNT Digital Library
Ecology for a changing earth (open access)

Ecology for a changing earth

To forecast the ecological impact of global change, research initiatives are needed on the explicit role of humans in ecological systems, and on how ecological processes functioning at different spatial and temporal scales are coupled. Furthermore, to synthesize the results of ecological research for Congress, policymakers, and the general public, a new agency, called the United States Ecological Survey (USES) is urgently required. Also, a national commitment to environmental health, as exemplified by establishing a National Institutes of the Environment (NIE), should be a goal.
Date: February 6, 1990
Creator: Brown, J.H. (New Mexico Univ., Albuquerque, NM (United States)) & Roughgarden, J. (Stanford Univ., CA (United States))
Object Type: Report
System: The UNT Digital Library
Portable code development in C (open access)

Portable code development in C

With a new generation of high performance computers appearing around us on a time scale of months, a new challenge for developers of simulation codes is to write and maintain production codes that are both highly portable and maximally efficient. My contention is that C is the language that is both best suited to that goal and is widely available today. GLF is a new code written mainly in C which is intended to have all of the XRASER physics and run on any platform of interest. It demonstrates the power of the C paradigm for code developers and flexibility and ease of use for the users. Three fundamental problems are discussed: the C/UNIX development environment; the supporting tools and libraries which handle data and graphics portability issues; and the advantages of C in numerical simulation code development.
Date: November 6, 1990
Creator: Brown, S.A.
Object Type: Article
System: The UNT Digital Library
Design of Long Induction Linacs (open access)

Design of Long Induction Linacs

A self-consistent design strategy for induction linacs is presented which addresses the issues of brightness preservation against space charge induced emittance growth, minimization of the beam breakup instability and the suppression of beam centroid motion due to chromatic effects (corkscrew) and misaligned focusing elements. A simple steering algorithm is described that widens the effective energy bandwidth of the transport system.
Date: September 6, 1990
Creator: Caporaso, G.J. & Cole, A.G.
Object Type: Article
System: The UNT Digital Library
The entropy in supernova explosions (open access)

The entropy in supernova explosions

The explosion of a supernova forms because of the collapse to a neutron star. In addition an explosion requires that a region of relatively high entropy be in contact with the neutron star and persisting for a relatively protracted period of time. The high entropy region ensures that the maximum temperature in contact with the neutron star and in hydrostatic equilibrium is less than some maximum. This temperature must be low enough such that neutrino emission cooling is small, otherwise the equilibrium atmosphere will collapse adding a large accretion mass to the neutron star. A so-called normal explosion shock that must reverse the accretion flow corresponding to a typical stellar collapse must have sufficient strength or pressure to reverse this flow and eject the matter with 10{sup 51} ergs for a typical type II supernova. Surprisingly the matter behind such a shock wave has a relatively low entropy low enough such that neutrino cooling would be orders of magnitude faster than the expansion rate. The resulting accretion low would be inside the Bondi radius and result in free-fall accretion inside the expanding rarefaction wave. The accreted mass or reimplosion mass unless stopped by a high entropy bubble could than exceed …
Date: December 6, 1990
Creator: Colgate, S. A.
Object Type: Article
System: The UNT Digital Library
Fish and Wildlife Service: Compensation to Local Governments (open access)

Fish and Wildlife Service: Compensation to Local Governments

The Refuge Revenue Sharing Fund (RRSF) was enacted in response to the concern of local governments regarding losses to their tax base due to the presence of federally owned land under the jurisdiction of the Fish and Wildlife Service. This report outlines recent history of RRSF payment levels. It examines the RRSF and describes how the fund differs in its treatment of reserved and acquired lands under the jurisdiction of FWS. The report also examines the Payment in Lieu of Taxes (PILT) program in detail.
Date: March 6, 1990
Creator: Corn, M. Lynne
Object Type: Report
System: The UNT Digital Library
Ionic two photon states and optical nonlinearity in. pi. -conjugated polymers (open access)

Ionic two photon states and optical nonlinearity in. pi. -conjugated polymers

A microscopic mechanism of optical nonlinearity in {pi}-conjugated polymers is presented. It is shown that the bulk of the nonlinearity is determined by only two well defined channels, even though an infinite number of channels are possible in principle. The above conclusion is true for both short and long range Coulomb interactions. The complete frequency dependence of the third harmonic generation in both trans-polyacetylene and polydiacetylene are explained within the same theoretical picture. 19 refs., 4 figs.
Date: November 6, 1990
Creator: Dixit, S.N. (Lawrence Livermore National Lab., CA (USA)); Guo, D. & Mazumdar, S. (Arizona Univ., Tucson, AZ (USA). Dept. of Physics)
Object Type: Article
System: The UNT Digital Library
Physics at the Planck scale (open access)

Physics at the Planck scale

Effective supergravity theories suggested by superstrings can be explored to determine their potential for successfully describing both observed physics at zero temperature and an inflationary cosmology. An important ingredient in this study is the dynamics of gaugino condensation, which has been the subject of recent activity. 33 refs., 2 figs.
Date: December 6, 1990
Creator: Gaillard, M.K. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)
Object Type: Article
System: The UNT Digital Library
German Unification (open access)

German Unification

This is a report on German Unification and the poliitical transformations in Germany.
Date: November 6, 1990
Creator: Gallis, Paul E. & Woehrel, Steven
Object Type: Report
System: The UNT Digital Library
Thermally Induced Structural Changes in Coal Combustion (open access)

Thermally Induced Structural Changes in Coal Combustion

Research continued on coal combustion. The project objectives are (1) to measure the effect of devolatilization temperature and time on the properties of the char and (2) characterize and quantify the effect of thermal annealing on char reactivity during char burnout under conditions of pulverized combustion. Work done during this reporting period includes: coal devolatilization/char generation; char oxidation in the thermogravimetric analyzer (TGA). Oxidation was conducted at 500{degree}C in a 5% O{sub 2}-N{sub 2} mixture at 150 cm{sup 3}/min flowrate. Under these conditions external and intraparticle diffusional limitations were negligible. Three chars obtained from the Pittsburgh No. 8 coal were used in the experiments; oxidation of single char particles in the electrodynamic balance. Experiments were carried out with particles from the Pittsburgh No. 8 char and a spherocarb'' synthetic char obtained from a vendor. The spherocarb char was used because the particles are nearly spherical thus avoiding the complications of irregular particle shape. 15 figs., 1 tab.
Date: December 6, 1990
Creator: Gavalas, G. R. & Flagan, R. C.
Object Type: Report
System: The UNT Digital Library
Diffusive transport enhancement by isolated resonances and distribution tails growth in hadronic beams (open access)

Diffusive transport enhancement by isolated resonances and distribution tails growth in hadronic beams

The escape rates and evolution of a distribution of particles are considered for a 2-D model of transverse motion of particles in hadronic storage rings, when nonlinear resonances and external diffusion are present. Dynamic enhancement of diffusion inside separatrices can develop under a certain geometry of resonance oscillations and relatively wide resonances, leading to the fast growth of distribution tails and escape rates. The phenomenon is absent in 1-D. 10 refs., 4 figs.
Date: December 6, 1990
Creator: Gerasimov, A.
Object Type: Article
System: The UNT Digital Library
Molten iron oxysulfide as a superior sulfur sorbent. First and second quarters progress report, September 1, 1989--March 1, 1990 (open access)

Molten iron oxysulfide as a superior sulfur sorbent. First and second quarters progress report, September 1, 1989--March 1, 1990

Slagging combustors with injected lime or limestone are being considered as replacements for conventional coal burners. They have advantages in that they can be staged to reduce NO{sub x} and SO{sub X} emissions. Iron oxide, as an alternative to lime or limestone may be effective not only as a desulfurizing agent, but, under the right conditions of oxygen potential, it can act as a flux to produce a glassy slag. This glassy slag should be dense and environmentally inert. In this reporting period, the thermodynamic conditions for the operation of the first stage of a combustor operating on a Illinois No. 2 Coal have been examined with respect to the formation of the four phase equilibrium: FeO(wustite)/Fe/liquid/gas over the temperature 950{degrees} to 1300{degrees}C. The minimum dosages of iron oxide which are required at equilibrium and the calculated maximum percent sulfur removal are reported. Also given are the expected pounds of So, per million Btu of heat evolution calculated for complete combustion. These preliminary results indicate that higher temperatures, in the range studied, give better results approaching 96 percent sulfur removal from a coal containing (on a dry basis) 3.29% by weight sulfur. A comparison is made between iron oxide and …
Date: March 6, 1990
Creator: Hepworth, M. T.
Object Type: Report
System: The UNT Digital Library
Molten iron oxysulfide as a superior sulfur sorbent. Technical progress report, September 1, 1989--March 1, 1990 (open access)

Molten iron oxysulfide as a superior sulfur sorbent. Technical progress report, September 1, 1989--March 1, 1990

Slagging combustors with injected lime or limestone are being considered as replacements for conventional coal burners. They have advantages in that they can be stages to reduce NO{sub x} and SO{sub x} emissions. Iron oxide, as an alternative to lime or-limestone may be effective not only as a desulfurizing agent, but, under the right conditions of oxygen potential, it can act as a flux to produce a glassy slag This glassy slag should be dense and environmentally inert. In this reporting period, the thermodynamic conditions for the operation of the first stage of a combustor operating on a Illinois No. 2 Coal have been examined with respect to the formation of the four phase equilibrium:FeO(wustite)/Fe/liquid/gas over the temperature 950{degree} to 1300{degree}C. The minimum dosages of iron oxide which are required at equilibrium and the calculated maximum percent sulfur removal are reported. Also given are the expected pounds of S per million Btu of heat SO{sub 2} evolution calculated for complete combustion. These preliminary results indicate that higher temperatures, in the range studied, give better results approaching 96 percent sulfur removal from a coal containing (on a dry basis) 3.29% by weight sulfur. A comparison is made between iron oxide and …
Date: March 6, 1990
Creator: Hepworth, M. T.
Object Type: Report
System: The UNT Digital Library
Layout of the LER (Low Energy Ring) Arc (open access)

Layout of the LER (Low Energy Ring) Arc

We have recently been trying to accumulate all of the information necessary to decide on the layout of the regular curved arcs of the Low Energy Ring (LER) and there have been several ABC Notes published on different aspects of the problem. This note will describe the layout that has been derived from these considerations.
Date: October 6, 1990
Creator: Hutton, A.
Object Type: Report
System: The UNT Digital Library
The OZI rule: A unique selector of glueballs and hadron spectroscopy (open access)

The OZI rule: A unique selector of glueballs and hadron spectroscopy

In the first part of this talk I have reviewed the history of the OZI rule. I then have shown how it is a unique selector glueballs and new quarks in hadron spectroscopy. In particular the only glueball candidates which cannot be explained by other hypotheses within QCD are the I{sup G}J{sup PC} = 0{sup +}2{sup ++} g{sub T}(2010), g{sub T},(2300) and g{sub T{double prime}}(2340) observed in the OZI suppressed reaction {pi}{sup {minus}} p {yields} {phi}{phi}n. The narrowness of the J/{psi} and T can only be explained by OZI suppression. I then reminisced about the 1954 Rochester Conference in which our work on {pi}{sup {plus minus}}p total cross sections and {pi}{sup {plus minus}} production combined gave convincing evidence for the delta being the first resonance. Described how the 1964 Dubna Conference results on small angle {pi}{sup {plus minus}}p elastic scattering led to the first critical experimental check of the pion-nucleon forward dispersion relations which showed that the basic axions of modern field theory worked on strong interactions at high energies. I finally reminisced about glueballs in the 1982 and 1988 Rochester Conferences. 52 refs., 17 figs., 3 tabs.
Date: August 6, 1990
Creator: Lindenbaum, S. J.
Object Type: Article
System: The UNT Digital Library
Data Report Documenting the Rattachment of the CC Cryostat Heads (open access)

Data Report Documenting the Rattachment of the CC Cryostat Heads

Reassembly of the inner pressure vessel of a seventeen foot diameter by ten foot long double wall toroidal shaped vessel in which each vessel consists of two concentric cylinders which are capped at each end by an annular dished head. Attached drawing 1, 2, 3, and 4 (all Revision 1) show the repair work items. The work covered by this data report applies only to the inner pressure vessel (See Item 8 remarks) . These work items are: (1) Two circumferential weld seams ( Seams A and G on attached drawing 2) of the north end annular dished head. (2) Two circumferential weld seams (Seam C and F on attached drawing 2) of the south end annular dished head. (3) Rerolling and rewelding of the vertical seam of the 64 3/8 inch nominal inside diameter tube (seam L on attached drawing 2) (4) Welding of the two dust catchers inside the inner pressure vessel (Seams Nand 0 on attached drawing 2). The dust catchers are attachments to pressure parts and were supplied by Fermi National Accelerator Laboratory. (5) Welding of the outer tube of the beam bypass tube (Seams I and K on attached drawing 3).
Date: November 6, 1990
Creator: Luther, R.
Object Type: Report
System: The UNT Digital Library
ASME Code Data Report for the CC Cryostat (open access)

ASME Code Data Report for the CC Cryostat

None
Date: November 6, 1990
Creator: Luther, Rick
Object Type: Report
System: The UNT Digital Library
Experimental development of nuclear pumped laser candidate for inertial confinement fusion driver. Technical progress report, Phase 2, 1989--1990 (open access)

Experimental development of nuclear pumped laser candidate for inertial confinement fusion driver. Technical progress report, Phase 2, 1989--1990

A report is given on progress made during the second year of a three year contract studying the feasibility of nuclear pumping the atomic iodine laser. Experimental results are presented showing efficiencies of 25--38% at converting neutron-induced nuclear reaction energy in the excimer XeBr into UV photons which can be used to pump the laser. Parametric studies were done utilizing the {sup 10}B(n,{alpha}){sup 7}Li reaction, with three bromine donor chemicals, over a range of pressures and mix ratios, to optimize the fluorescence efficiency.
Date: June 6, 1990
Creator: Miley, G. H.
Object Type: Report
System: The UNT Digital Library
Experimental development of nuclear pumped laser candidate for inertial confinement fusion driver (open access)

Experimental development of nuclear pumped laser candidate for inertial confinement fusion driver

A report is given on progress made during the second year of a three year contract studying the feasibility of nuclear pumping the atomic iodine laser. Experimental results are presented showing efficiencies of 25--38% at converting neutron-induced nuclear reaction energy in the excimer XeBr into UV photons which can be used to pump the laser. Parametric studies were done utilizing the {sup 10}B(n,{alpha}){sup 7}Li reaction, with three bromine donor chemicals, over a range of pressures and mix ratios, to optimize the fluorescence efficiency.
Date: June 6, 1990
Creator: Miley, George H.
Object Type: Report
System: The UNT Digital Library
Superclean coal-water slurry combustion testing in an oil-fired boiler. Quarterly technical progress report, November 15, 1989--February 15, 1990 (open access)

Superclean coal-water slurry combustion testing in an oil-fired boiler. Quarterly technical progress report, November 15, 1989--February 15, 1990

The Pennsylvania State University is conducting a superclean coal-water slurry (SCCWS) program for the US Department of Energy (DOE) and the Commonwealth of Pennsylvania with the objective of demonstrating the capability of effectively firing SCCWS in industrial boilers designed for oil. Penn State has entered into a cooperative agreement with DOE to determine if SCCWS (a fuel containing coal with less than 3% ash and 0.9% sulfur) can effectively be burned in oil-designed industrial boilers without adverse impact on boiler rating, maintainability, reliability, and availability. The project will provide information on the design of new systems specifically configured to fire these clean coal-based fuels. The project consists of three phases: (1) design, permitting, and test planning, (2) construction and start up, and (3) operations and disposition. The boiler testing will determine if the SCCWS combustion characteristics, heat release rate, slagging and fouling factors, erosion and corrosion limits, and fuel transport, storage, and handling can be accommodated in an oil-designed boiler. In addition, the proof-of-concept demonstration will generate data to determine how the properties of SCCWS and its parent coal affect boiler performance. Economic factors associated with retrofitting and operating boilers will be identified to assess the viability of future oil-to-coal …
Date: April 6, 1990
Creator: Miller, B. G.; Walsh, P. M.; Elston, J. T. & Scaroni, A. W.
Object Type: Report
System: The UNT Digital Library
Superclean coal-water slurry combustion testing in an oil-fired boiler. Quarterly technical progress report, August 15--November 15, 1989 (open access)

Superclean coal-water slurry combustion testing in an oil-fired boiler. Quarterly technical progress report, August 15--November 15, 1989

The Pennsylvania State University is conducting a superclean coal-water slurry (SCCWS) program for the US Department of Energy (DOE) and the Commonwealth of Pennsylvania with the objective of demonstrating the capability of effectively firing SCCWS in industrial boilers designed for oil. Penn State has entered into a cooperative agreement with DOE to show that SCCWS (a fuel containing coal with less than 3% ash and 0.9% sulfur) can effectively be burned in oil-designed industrial boilers without adverse impact on boiler rating, maintainability, reliability, and availability. The project will provide information on the design of new systems specifically configured to fire these clean coal-based fuels. The project consists of three phases: (1) design, permitting, and test planning, (2) construction and start up, and (3) operations and disposition. The boiler testing will determine if the SCCWS combustion characteristics, heat release rate, slagging and fouling factors, erosion and corrosion limits, and fuel transport, storage, and handling can be accommodated in an oil-designed boiler. In addition, the proof-of-concept demonstration will generate data to determine how the properties of SCCWS and its parent coal affect boiler performance. Economic factors associated with retrofitting and operating boilers will be identified to assess the viability of future oil-to-coal …
Date: April 6, 1990
Creator: Miller, B.G. & Scaroni, A.W.
Object Type: Report
System: The UNT Digital Library
A high resolution capacitive imaging sensor for manufacturing applications (open access)

A high resolution capacitive imaging sensor for manufacturing applications

A high resolution capacitive image sensing technique for measuring edge and surface profiles during manufacturing processes has been invented. A prototype device utilizing this technique consists of two 0.020 in. (500 {mu}m) diameter electrodes fabricated on a printed circuit board with a 0.010 in. (250 {mu}m) gap between them. As the device is mechanically scanned over the workpiece, the spatial variations in the edge or surface to be measured interfere with an electric field imposed between the electrodes, altering the mutual capacitance. The sensor functions as a near field proximity sensor producing range images of surface imperfections. This sensor has been used in applications requiring a preview image of burrs on the edge of a machined part and other processes requiring an inspection image after automated deburring operations. 10 refs., 8 figs.
Date: September 6, 1990
Creator: Novak, J. L. & Wiczer, J. J.
Object Type: Article
System: The UNT Digital Library
Changes in Fe site occupancy and Tc in YBa sub 2 (Cu sub 1-x Fe sub x ) sub 3 O sub y through processing (open access)

Changes in Fe site occupancy and Tc in YBa sub 2 (Cu sub 1-x Fe sub x ) sub 3 O sub y through processing

Fe substitution for Cu in YBa{sub 2}Cu{sub 3}O{sub y} can give information about the local environment on the two crystallographic Cu sites through Mossbauer effect measurements. In this paper, we explore the possibility of forcing larger amounts of Fe onto the Cu (2) site which represents the CuO planes. At values near y = 6, the chain Cu (1) site is characteristic for Cu{sup +} in its linear 0 coordination and should preclude Fe occupation. We therefore prepared materials at elevated temperatures under N{sub 2} where y {approximately}6. Oxygenation to y {approximately}7 was achieved at temperatures where metal diffusion is minimized. We used Mossbauer spectroscopy to determine the Fe site occupancy. Site preference can be expressed in terms of a distribution ratio r = MCul/ MCu2. Creating materials with low r allows studying the effects of spatially constrained Fe on T{sub c}, separating influences from the spatially more complex Cu (1) site.
Date: April 6, 1990
Creator: Oesterreicher, H. (California Univ., San Diego, CA (USA)); Smith, M.G. (Los Alamos National Lab., NM (USA) California Univ., San Diego, CA (USA)) & Taylor, R.D. (Los Alamos National Lab., NM (USA))
Object Type: Article
System: The UNT Digital Library