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Successful Spawning of Orangemouth Corvina Following Injection with des-Gly^10, [d-Ala^6] - Luteinizing Hormone-Releasing Hormone (1-9) Ethylamide and Pimozide (open access)

Successful Spawning of Orangemouth Corvina Following Injection with des-Gly^10, [d-Ala^6] - Luteinizing Hormone-Releasing Hormone (1-9) Ethylamide and Pimozide

Report on the experimentation to spawn mature orangemouth corvina with hormone injections.
Date: August 1987
Creator: Prentice, John A. & Thomas, Peter
System: The Portal to Texas History
The two-beam accelertor (open access)

The two-beam accelertor

The Two-Beam Accelerator (TBA) consists of a long high-gradient accelerator structure (HGS) adjacent to an equal-length Free Electron Laser (FEL). In the FEL, a beam propagates through a long series of undulators. At regular intervals, waveguides couple microwave power out of the FEL into the HGS. To replenish energy given up by the FEL beam to the microwave field induction accelerator units are placed periodically along the length or the FEL. In this manner it is expected to achieve gradients of more than 250 MV/m and thus have serious option for a 1 TeV /times/ 1 TeV linear collider. The state of present theoretical understanding of the TBA is presented with particular emphasis upon operation of the ''steady-state'' FEL, phase and amplitude control of the rf wave, and suppression of sideband instabilities. Experimental work has focused upon the development of a suitable HGS and the testing of this structure using the Electron Laser Facility (ELF). Description is given of a first test at ELF with a seven-cell 2..pi../3 mode structure which without pre-conditioning and with a not-very-good vacuum nevertheless at 35 GHz yielded an average accelerating gradient of 180 MV/m.
Date: August 1, 1987
Creator: Sessler, A. M. & Hopkins, D. B.
System: The UNT Digital Library
Radial Wire Drift Chambers for CDF Forward Tracking (open access)

Radial Wire Drift Chambers for CDF Forward Tracking

We describe the design, construction, and operating experience of unique drift chambers with radially strung wires for the Collider Detector of Fermilab (CDF) [1] which cover forward ad backward cone angles between 2{sup o} and 10{sup o} and 170{sup o} to 178{sup o}. The chambers are capable of operating in our high rate and high track multiplicity environment with excellent multitrack resolution of 2-3 mm and high tracking accuracy of 140 {micro}m per wire. Results from the recent running experience will be presented.
Date: August 1, 1987
Creator: Atac, M.; Foster, G. W.; Newman-Holmes, C.; Para, A.; Patrick, J.; Sekiguchi, M. et al.
System: The UNT Digital Library
Luminance in computer-aided lighting design (open access)

Luminance in computer-aided lighting design

Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually ``sees``. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its …
Date: August 1, 1987
Creator: Ward, G. J.; Rubinstein, F. M. & Grynberg, A.
System: The UNT Digital Library
Luminance in computer-aided lighting design (open access)

Luminance in computer-aided lighting design

Traditionally, the lighting engineering community has emphasized illuminance, the amount of light reaching a surface, as the primary design goal. The Illuminating Engineering Society (IES) provides tables of illuminances for different types of tasks which lighting engineers consult in designing lighting systems. Illuminance has proven to be a popular metric because it corresponds closely to the amount of energy needed to light a building as well as the initial cost of the lighting system. Perhaps more importantly, illuminance is easy to calculate, especially in simple unobstructed spaces with direct lighting. However,illuminance is not well correlated with visual performance, which is the real reason for installing a lighting system in the first place. Visual performance is a psychophysiological quantity that has been tied to physical quantities such as contrast, size and adaptation level by subject experiments. These physical quantities can be approximated from illuminance using a host of assumptions about the environment, or derived directly from the distribution of luminance. Luminance is the quantity of light traveling through a point in a certain direction, and it is this quantity that the eye actually sees''. However, the difficulty of calculating luminance for common tasks has made it an unpopular metric. Despite its …
Date: August 1, 1987
Creator: Ward, G.J.; Rubinstein, F.M. & Grynberg, A.
System: The UNT Digital Library
Use of expert systems in nuclear power plants (open access)

Use of expert systems in nuclear power plants

None
Date: August 1, 1987
Creator: Uhrig, Robert E.
System: The UNT Digital Library
A summary of the low angle x-ray atomic scattering factors which have been measured by the critical voltage effect in High Energy Electron Diffraction (HEED) (open access)

A summary of the low angle x-ray atomic scattering factors which have been measured by the critical voltage effect in High Energy Electron Diffraction (HEED)

A tabulated summary of all the accurate (/approximately/0.1%) low-angle x-ray atomic scattering (form) factors which have been determined by the systematic critical voltage technique in HEED is presented. For low atomic number elements (Z/approx lt/40) the low angle form factors can be significantly different to best free atom values, and so the best band structure calculated and/or x-ray measured form factors consistent with the critical voltage measurements are also indicated. At intermediate atomic numbers Zapprox. =40..-->..50 only the very low-angle form factors appear to be different to the best free atom values, and even then only by a small amount. For heavy elements (Z/approx lt/70) the best free atom form factors appear to agree very closely with the critical voltage measured values and so, in this case, critical voltage measurements give very accurate measurements of Debye-Waller factors. 48 refs.
Date: August 1, 1987
Creator: Fox, A.G. & Fisher, R.M.
System: The UNT Digital Library
Photon energy tunability of advanced photon source undulators (open access)

Photon energy tunability of advanced photon source undulators

At a fixed storage ring energy, the energy of the harmonics of an undulator can be shifted or ''tuned'' by changing the magnet gap of the device. The possible photon energy interval spanned in this way depends on the undulator period, minimum closed gap, minimum acceptable photon intensity and storage ring energy. The minimum magnet gap depends directly on the stay clear particle beam aperture required for storage ring operation. The tunability of undulators planned for the Advanced Photon Source with first harmonic photon energies in the range of 5 to 20 keV are discussed. The results of an analysis used to optimize the APS ring energy is presented and tunability contours and intensity parameters are presented for two typical classes of devices.
Date: August 1, 1987
Creator: Viccaro, P. J. & Shenoy, G. K.
System: The UNT Digital Library
Experimental Studies of Electromagnetic Properties of Few Body Systems (open access)

Experimental Studies of Electromagnetic Properties of Few Body Systems

An overview is given of some recent and planned experiments which have or will substantially increase our knowledge of the electromagnetic properties of few body systems. Specific examples include the proton and neutron elastic form factors, the deuteron elastic form factors, deuteron threshold electrodisintegration and quasi-elastic scattering, deuteron photodisintegration, and finally measurements of cross sections in deep inelastic scattering from hydrogen, deuterium, and iron. 47 refs., 13 figs. (DWL)
Date: August 1, 1987
Creator: Bosted, P. E.
System: The UNT Digital Library
The role of pre-equilibrium theory in nuclear data evaluation (open access)

The role of pre-equilibrium theory in nuclear data evaluation

We illustrate the utility of preequilibrium plus equilibrium decay models in reproducing neutron and ..gamma..-ray spectra for incident nucleons of approx. = 2 to 20 MeV. We discuss models and theories for calculating preequilibrium nucleon angular distributions and the short comings involved. Attention is focussed on special problems in modelling preequliibrium reactions for target nuclei near shell closures, and possible ways to improve the modelling in these regimes by use of shell model levels to generate few quasi-particle state densities. We show preliminary tests of applicability of preequilibrium models to incident nucleon energies up to 1 GeV and for heavy ion induced reactions at energies up to 300 MeV, areas where modern technology is increasingly seeking nuclear data input. 40 refs., 16 figs.
Date: August 1, 1987
Creator: Blann, M.
System: The UNT Digital Library
Production and propagation of mesons in complex nuclei (open access)

Production and propagation of mesons in complex nuclei

The propagation of unstable mesons in nuclei is considered with regard to the use of the nucleus as a micro-laboratory. Specific problems considered are those of the nu and the S*/delta systems. 17 refs., 12 figs.
Date: August 1987
Creator: Gibbs, W.R. & Kaufmann, W.B.
System: The UNT Digital Library
Fully developed turbulence via Feigenbaum's period-doubling bifurcations (open access)

Fully developed turbulence via Feigenbaum's period-doubling bifurcations

Since its publication in 1978, Feigenbaum's predictions of the onset of turbulence via period-doubling bifurcations have been thoroughly borne out experimentally. In this paper, Feigenbaum's theory is extended into the regime in which we expect to see fully developed turbulence. We develop a method of averaging that imposes correlations in the fluctuating system generated by this map. With this averaging method, the field variable is obtained by coarse-graining, while microscopic fluctuations are preserved in all averaging scales. Fully developed turbulence will be shown to be a result of microscopic fluctuations with proper averaging. Furthermore, this model preserves Feigenbaum's results on the physics of bifurcations at the onset of turbulence while yielding additional physics both at the onset of turbulence and in the fully developed turbulence regime.
Date: August 1, 1987
Creator: Duong-van, M.
System: The UNT Digital Library
Physical and chemical characteristics and development of the Changuinola peat deposit of northwestern Panama (open access)

Physical and chemical characteristics and development of the Changuinola peat deposit of northwestern Panama

A peat deposit occupying over 80 square kilometers, and averaging 8 meters in thickness, was discovered on the Caribbean coast of northwestern Panama near the town of Changuinola. This deposit occurs inland (behind) the present beach-barrier shoreline. It is thickest in the center and thins toward all edges (as if domed). The surface vegetation in the central regions consists primarily of ombrotrophic plants (especially sedges, grasses, Sphagnum, Sagittaria, and various scattered shrubs). Toward the edges, the deposit has a surface cover of more minerotrophic plants (such as swamp-forest trees, ferns, and palms). Petrographic/botanical analysis of the deposit with depth reveals the presence of five peat types (swamp-forest, sedge-grass-fern, Sagittaria et al., Nymphaea et al., and Rhizophora). Typically peats of the thick, central portions of the deposit are very low in ash and sulfur (less than 2% ash and 0.3% sulfur). Ash contents tend to increase abruptly at the base and more gradually toward the edges of the deposit and sulfur contents increasing gradually toward the ocean and bay. Vertical and lateral variations in botanical, chemical, and physical properties of this deposit can be related to factors that have controlled: (1) the surrounding rocks and water chemistry; (2) the source vegetation; …
Date: August 1, 1987
Creator: Cohen, A.D.; Raymond, R. Jr.; Thayer, G. & Ramirez, A.
System: The UNT Digital Library
GOLD: Integration of model-based control systems with artificial intelligence and workstations (open access)

GOLD: Integration of model-based control systems with artificial intelligence and workstations

Our experience with model-based accelerator control started at SPEAR. Since that time nearly all accelerator beamlines have been controlled using model-based application programs, for example, PEP and SLC at SLAC. In order to take advantage of state-of-the-art hardware and software technology, the design and implementation of the accelerator control programs have undergone radical changes with time. Consequently, SPEAR, PEP and SLC all use different control programs. Since many of these application programs are embedded deep into the control system, they had to be rewritten each time. Each time this rewriting has occurred a great deal of time and effort has been spent on training physicists and programmers to do the job. Now, we have developed an integrated system called GOLD (Genetic Orbit and Lattice Debugger) for debugging and correcting trajectory errors in accelerator lattices. The system consists of a lattice modeling program (COMFORT), a beam simulator (PLUS), a graphical workstation environment (micro-VAX) and an expert system (ABLE). This paper will describe some of the features and applications of our integrated system with emphasis on the automation offered by expert systems. 5 refs.
Date: August 1, 1987
Creator: Lee, M. & Clearwater, S.
System: The UNT Digital Library
Nuclear stopping and energy deposition into the central rapidity region (open access)

Nuclear stopping and energy deposition into the central rapidity region

Nuclear stopping and energy deposition into the central rapidity region of ultrarelativistic heavy-ion collisions are studied through the application of a model incorporating hydrodynamic baryon flow coupled to a self-consistent field calculated in the flux tube model. Ultrarelativistic heavy ion collisions are modeled in which the nuclei have passed through each other and as a result are charged and heated.
Date: August 3, 1987
Creator: Zingman, J.A.
System: The UNT Digital Library
Evidence for bimodal fission in the heaviest elements (open access)

Evidence for bimodal fission in the heaviest elements

We have measured the mass and kinetic-energy partitioning in the spontaneous fission of five heavy nuclides: /sup 258/Fm, /sup 259/Md, /sup 260/Md /sup 258/No, and /sup 260/(104). Each was produced by heavy-ion reactions with either /sup 248/Cm, /sup 249/Bk, or /sup 254/Es targets. Energies of correlated fragments from the isotopes with millisecond half lives, /sup 258/No and /sup 260/(104), were measured on-line by a special rotating-wheel instrument, while the others were determined off-line after mass separation. All fissioned with mass distributions that were symmetric. Total-kinetic-energy distributions peaked near either 200 or 235 MeV. Surprisingly, because only a single Gaussian energy distribution had been observed previously in actinide fission, these energy distributions were skewed upward or downward from the peak in each case, except for /sup 260/(104), indicating a composite of two energy distributions. We were able to fit accurately two Gaussian curves to the gross energy distributions from the four remaining nuclides. From the multiple TKE distributions and the shapes of the mass distributions, we conclude that there is a low-energy fission component with liquid-drop characteristics which is admixed with a much higher-energy component due to closed fragment shells. We now have further evidence for this conclusion from measurements of …
Date: August 1, 1987
Creator: Hulet, E. K.; Wild, J. F.; Lougheed, R. W.; Dougan, R. J.; Landrum, J. H.; Dougan, A. D. et al.
System: The UNT Digital Library
Magnetic mirror fusion systems: Characteristics and distinctive features (open access)

Magnetic mirror fusion systems: Characteristics and distinctive features

A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.
Date: August 10, 1987
Creator: Post, Richard F.
System: The UNT Digital Library
Fossil Energy Materials Program conference proceedings (open access)

Fossil Energy Materials Program conference proceedings

The US Department of Energy Office of Fossil Energy has recognized the need for materials research and development to assure the adequacy of materials of construction for advanced fossil energy systems. The principal responsibility for identifying needed materials research and for establishing a program to address these needs resides within the Office of Technical Coordination. That office has established the Advanced Research and Technology Development (AR and TD) Fossil Energy Materials Program to fulfill that responsibility. In addition to the AR and TD Materials Program, which is designed to address in a generic way the materials needs of fossil energy systems, specific materials support activities are also sponsored by the various line organizations such as the Office of Coal Gasification. A conference was held at Oak Ridge, Tennessee on May 19-21, 1987, to present and discuss the results of program activities during the past year. The conference program was organized in accordance with the research thrust areas we have established. These research thrust areas include structural ceramics (particularly fiber-reinforced ceramic composites), corrosion and erosion, and alloy development and mechanical properties. Eighty-six people attended the conference. Papers have been entered individually into EDB and ERA. (LTN)
Date: August 1, 1987
Creator: Judkins, R.R. (comp.)
System: The UNT Digital Library
Ground state partial radiative widths of /sup 207/Pb + n resonances and M1 and E2 strengths in /sup 208/Pb (open access)

Ground state partial radiative widths of /sup 207/Pb + n resonances and M1 and E2 strengths in /sup 208/Pb

Ground state partial radiative widths of neutron resonances in /sup 207/Pb + n have been measured. A resonance analysis has been carried out in a complete manner below 700 keV neutron energy, and for selected strongly radiation resonances up to 1 MeV. The total magnetic dipole strength detected above neutron separation energy is only 6.8 ..mu../sub 0//sup 2/, but the observed appreciable fragmentation of the M1 strength suggests that considerable strength is missed at excitation energies above 8 MeV. The electric quadrupole strength observed between neutron separation energy and 8.2 MeV is distributed rather uniformly, and corresponds to 4.9% of the energy-weighted sum-rule for isoscalar E2 transitions. 10 refs., 2 figs.
Date: August 1, 1987
Creator: Weigmann, H.; Koehler, R.; Poortmans, F.; Raman, S. & Wartena, J.A.
System: The UNT Digital Library
The role of basic research in society (open access)

The role of basic research in society

This report contains general remarks on the rate of accelerators, especially the Superconducting Super Collider, in the advancement of modern scientific knowledge. (LSP)
Date: August 1, 1987
Creator: Seaborg, G. T.
System: The UNT Digital Library
Single leptons from heavy quark production (open access)

Single leptons from heavy quark production

We consider the single lepton decay mode of heavy quarks as a signature of heavy quark pair production at the SSC. We find that events with multijets (n/sub jet/ greater than or equal to 3) and a single high p/sub T/ lepton are a good signal for heavy quark production.
Date: August 1, 1987
Creator: Dawson, S. & Godfrey, S.
System: The UNT Digital Library
Experimental results from TMX-U. [Tandem Mirror Experiment-Update] (open access)

Experimental results from TMX-U. [Tandem Mirror Experiment-Update]

This paper presents the recent results from the Tandem Mirror Experiment-Update(TMX-U). Many of these results can be divided into two major areas: (1) axial confinement and plasma potential, and (2) radial transport and total confinement (i.e., particle balance). Among the key observations to be discussed are the following: When the ion-confining potential theta/sub ic/ is small, theta/sub ic//T/sub i/ approx. 1 to 2, the axial confinement time scales as the theoretical Pastukhov time. Deep thermal barriers (theta/sub b/ approx. 0.7 kV, theta/sub b//T/sub e/ approx. 6 to 7) have been measured, but there is no strong correlation between ion-confining potential and the thermal-barrier depth. By installing a calibrated H/sub ..cap alpha../ emission diagnostic to measure the ionization current, we have quantified particle balance between the ionization source current and the four plasma current channels: (1) axial losses, (2) nonambipolar radial losses, (3) ambipolar radial losses, and (4) density changes. All current channels are directly measured except for the ambipolar current, which is inferred from the particle balance equation. TMX-U operation above 1 to 3 x 10/sup 12/ cm/sup -3/ is dominated by current channel (1) and below 1 x 10/sup 12/ cm/sup -3/ by one or more of the remaining …
Date: August 1, 1987
Creator: Correll, D.L.
System: The UNT Digital Library
Relativistic nuclear fluid dynamics and VUU kinetic theory (open access)

Relativistic nuclear fluid dynamics and VUU kinetic theory

Relativistic kinetic theory may be used to understand hot dense hadronic matter. We address the questions of collective flow and pion production in a 3 D relativistic fluid dynamic model and in the VUU microscopic theory. The GSI/LBL collective flow and pion data point to a stiff equation of state. The effect of the nuclear equation of state on the thermodynamic parameters is discussed. The properties of dense hot hadronic matter are studied in Au + Au collisions from 0.1 to 10 GeV/nucleon. 22 refs., 5 figs.
Date: August 24, 1987
Creator: Molitoris, J.J.; Hahn, D.; Alonso, C.; Collazo, I.; D'Alessandris, P.; McAbee, T. et al.
System: The UNT Digital Library
Production of strange particles in hadronization processes (open access)

Production of strange particles in hadronization processes

Strange particles provide an important tool for the study of the color confinement mechanisms involved in hadronization processes. We review data on inclusive strange-particle production and on correlations between strange particles in high-energy reactions, and discuss phenomenological models for parton fragmentation. 58 refs., 24 figs.
Date: August 1, 1987
Creator: Hofmann, W.
System: The UNT Digital Library