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A 3-D dynamical/chemical GCM for simulating the anthropogenical effects on ozone (open access)

A 3-D dynamical/chemical GCM for simulating the anthropogenical effects on ozone

In spite of the significantly increased attention atmospheric ozone has received over the last two decades or so, a fully quantitative understanding of the three-dimensional ozone structure remains unavailable. In the past, one-dimensional (vertical column) models have provided most of the quantitative simulations of atmospheric chemical systems, because these models can treat large ensembles of chemical process economically. More recently, two-dimensional (meridional cross section) models have become popular, in part because of increasing computer capabilities. There has been little work using a sophisticated 3-D GCM coupled with a comprehensive photochemical model to study the chemical-dynamical interactions involving the ozone abundance. Namely, either the dynamics or the chemistry is too simplified in most of the existing models. Relatively more advanced photochemistry has been included in the stratospheric models (dealing the vertical domain from 20 to 70 km above the surface) at the expense of tropospheric details. An important motivation for this research has been the desire to estimate the magnitude of changes in the ozone layer induced by anthropogenic perturbations such as the injection of oxides of nitrogen and chlorine compounds. Accordingly, the attempt has been to develop a complete but feasible photochemical scheme and to combine it with the Los …
Date: January 1, 1989
Creator: Kao, C. Y. J.; Glatzmaier, G. A.; Malone, R. C. & Turco, R. P.
System: The UNT Digital Library
3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters (open access)

3-D heat transfer computer calculations of the performance of the IAEA's air-bath calorimeters

A three dimensional (3-D) heat transfer computer code was developed to study and optimize the design parameters and to better understand the performance characteristics of the IAEA's air-bath calorimeters. The computer model accounts for heat conduction and radiation in the complex materials of the calorimeter and for heat convection and radiation at its outer surface. The temperature servo controller is modelled as an integral part of the heat balance equations in the system. The model predictions will be validated against test data using the ANL bulk calorimeter. 11 refs., 6 figs.
Date: January 1, 1989
Creator: Elias, E.; Kaizermann, S.; Perry, R. B. & Fiarman, S.
System: The UNT Digital Library
A 3-D measurement system using object-oriented FORTH (open access)

A 3-D measurement system using object-oriented FORTH

Discussed is a system for storing 3-D measurements of points that relates the coordinate system of the measurement device to the global coordinate system. The program described here used object-oriented FORTH to store the measured points as sons of the measuring device location. Conversion of local coordinates to absolute coordinates is performed by passing messages to the point objects. Modifications to the object-oriented FORTH system are also described. 1 ref.
Date: January 1, 1989
Creator: Butterfield, K.B.
System: The UNT Digital Library
3-D structures and intrinsic defects in trans-polyacetylene (open access)

3-D structures and intrinsic defects in trans-polyacetylene

We report first-principles local-density functional pseudopotential calculations of static and dynamic electronic structure properties of crystalline 3-D trans--(CH)/sub x/. We find a broken symmetry ground state of P2/sub 1//a symmetry with in-phase dimerizations. Using a Green's function technique, we show that the 3-D character of the electronic band edge states strongly suppresses self-trapping, destabilizing polarons and possibly bipolarons as well in perfectly ordered 3-D trans--(CH)/sub x/. 26 refs.
Date: January 1, 1989
Creator: Vogl, Peter & Campbell, David K.
System: The UNT Digital Library
A 14-MeV beam-plasma neutron source for materials testing (open access)

A 14-MeV beam-plasma neutron source for materials testing

The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m{sup 2} at the plasma surface are produced by D-T reactions in a two-component plasma. In the present designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection of 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source, in dimensionless units, have been achieved in the 2XIIB high-{beta} plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron source design. In the extrapolation, care has been taken to preserve the scaling and plasma attributes that contributed to equilibrium, magnetohydrodynamic (MHD) stability, and microstability in 2XIIB. The performance and scaling characteristics are described for several designs chosen …
Date: January 1, 1989
Creator: Futch, A. H.; Coensgen, F. H.; Damm, C. C. & Molvik, A. W.
System: The UNT Digital Library
A 30 MW, 10 GHz Gyroklystron With Linear Collider Application (open access)

A 30 MW, 10 GHz Gyroklystron With Linear Collider Application

In this paper, the final preparations for bringing the University of Maryland's 10 GHz, 30 MW gyroklystron experiment on-line are discussed. We describe the initial operation of the modulator and the acceptance tests performed on the electron gun. We explain the enhanced circuit modelling and present a two-cavity design which predicts an efficiency of 33% and a gain of 27 dB. The realization of the design is also discussed. In addition, we briefly discuss the output waveguide and the diagnostics for beam and rf characterization. Finally, a four-cavity circuit design is presented with its predicted operating parameters that can achieve the necessary gain and efficiency required for accelerator application. 14 refs., 11 figs., 5 tabs.
Date: January 1, 1989
Creator: Lawson, W.; Latham, P.E.; Calame, J.; Skopec, M.; Welsh, D.; Hogan, B. et al.
System: The UNT Digital Library
The 1989 outburst of V404 Cygni: A very unusual x-ray nova (open access)

The 1989 outburst of V404 Cygni: A very unusual x-ray nova

On May 22, 1989, the Japanese Ginga Team discovered a new x-ray source that was cataloged as GS 2023+338. This source was subsequently identified as coincident in position with a previously known nova cataloged as V404 Cygni. Its last recorded outburst was in 1938 when it rose to about 12th mag. Spectroscopic data were obtained and confirmed the nature of the outburst. Additional ground based data were obtained by us at CTIO and the VLA. The x-ray behavior of this object has been reported to be very unusual and it reached a peak of about 17 crab about one week after discovery. Since then it has varied widely in magnitude at all wavelengths at which it has been studied. We present a brief summary of the observations that have been obtained up to the time of the meeting and shortly thereafter. 5 refs., 3 figs.
Date: January 1, 1989
Creator: Wagner, R. M.; Collins, G. W.; Bertram, R. (Ohio State Univ., Columbus, OH (USA). Dept. of Astronomy); Starrfield, S. (Los Alamos National Lab., NM (USA) Arizona State Univ., Tempe, AZ (USA)); Cassatella, A.; Gonzalez-Riestra, R. et al.
System: The UNT Digital Library
1989 report on the IAEA research agreement No. 4412/CF (open access)

1989 report on the IAEA research agreement No. 4412/CF

My contribution to this CRP is the provision of double-differential neutron-scattering cross section data on the mono-isotopic elements Nb, Rh, In, Ho, Ta, Au, and Bi. These data cover the ranges incident neutron energies, E{sub in} = 5--8 Mev, angular range, 30--158 {degrees}, excitation energies, {approx} 2 to E{sub in}--1 MeV. In this report I will briefly review the original purpose of these measurements, indicate the assumptions and procedures required to obtain the requested cross sections, present the results of this effort, give a few examples of how these results compare to calculations made with relevant nuclear model codes, describe the data files that I have prepared for the participants of this CRP, briefly describe sources of error. An appendix contains a short discussion of some experimental concerns. 8 refs., 9 figs.
Date: January 1, 1989
Creator: Guenther, P. T.
System: The UNT Digital Library
2000 MCM electrical power jumper cable with controlled flexibility: Design and life cycle test (open access)

2000 MCM electrical power jumper cable with controlled flexibility: Design and life cycle test

The ZTH Reversed Field Pinch (RFP) plasma confinement experiment being built at the Los Alamos National Laboratory will use magnet coils to provide ohmic heating currents in the plasma. The ohmic heating coils are supported by a structure that will allow them limited movement with respect to surrounding hardware and the connecting electrical bus work. To minimize displacement-induced stresses in the coils, flexible'' power conducting links are necessary to accommodate the relative motion between the bus work and the coils. A semi-flexible 2000 MCM jumper cable has been designed with enough flexibility to allow free movement of the coils, yet it is stiff enough to withstand large magnetically-induced lateral loads and minimize the effect of the lateral loads on the magnet coil leads. A full-power life cycle test of the jumper was performed under magnetic, thermal and dynamic loads that closely simulate the expected operating conditions. This test evaluated the structural and electrical integrity of the jumper as well as the quality and reliability of the bolted electrical connections at the jumper ends in a high-stress, cyclic-loading environment. The jumper cable design is presented with an explanation of the requirements for a semi-flexible link. A description of the life cycle …
Date: January 1, 1989
Creator: Bultman, D.H.; Sims, J.R. & Reass, W.A.
System: The UNT Digital Library
Absorption experiments on electorn-beam pumped rare gases (open access)

Absorption experiments on electorn-beam pumped rare gases

Absorption experiments have been performed on electron-beam pumped rare gases (argon and krypton) as a function of pump power using the frequency-doubled output of a tunable dye laser at 248.4 nm and 257.3 nm. Energy deposition into the gas was varied by attenuating the electron beam with one or two stainless steel screens and by filling the gas chamber with different rare gas densities. The results from two energy deposition diagnostics were compared, and found to agree within 20%. Kinetics code calculations agreed with experimental results when absorption cross sections in the code were lowered. 9 refs., 12 figs., 2 tabs.
Date: January 1, 1989
Creator: McCown, A. W.; Rose, E. A.; Krohn, B. J.; Hanson, D. E. & Czuchlewski, S. J.
System: The UNT Digital Library
Acceleration of metal plates (open access)

Acceleration of metal plates

High-explosive charges have been used to accelerate stainless steel plates to velocities of 6-7 km/s. A two-stage system has been used in which the first stage is a plane-wave detonating system that accelerates the plate down a short barrel. The second stage consists of a hollow cylindrical charge through which the moving plate passes. After an adjustable delay this charge is detonated on the outer circumference of the entry side of the charge. Flash radiographs and witness plates show no breakup in the first stage but bowing and frequent breakup in the second stage. 6 figs.
Date: January 1, 1989
Creator: Marsh, S. P.; McQueen, R. G. & Tan, T. H.
System: The UNT Digital Library
Acceleration of Small, Light Projectiles (Including Hydrogen Isotopes) to High Speeds Using a Two-Stage Light Gas Gun (open access)

Acceleration of Small, Light Projectiles (Including Hydrogen Isotopes) to High Speeds Using a Two-Stage Light Gas Gun

Small, light projectiles have been accelerated to high speeds using a two-stage light gas gun at Oak Ridge National Laboratory. With 35-mg plastic projectiles (4 mm in diameter), speeds of up to 4.5 km/s have been recorded. The pipe gun'' technique for freezing hydrogen isotopes in situ in the gun barrel has been used to accelerate deuterium pellets (nominal diameter of 4 mm) to velocities of up to 2.85 km/s. The primary application of this technology is for plasma fueling of fusion devices via pellet injection of hydrogen isotopes. Conventional pellet injectors are limited to pellet speeds in the range 1-2 km/s. Higher velocities are desirable for plasma fueling applications, and the two-stage pneumatic technique offers performance in a higher velocity regime. However, experimental results indicate that the use of sabots to encase the cryogenic pellets and protect them for the high peak pressures will be required to reliably attain intact pellets at speeds of {approx}3 km/s or greater. In some limited tests, lithium hydride pellets were accelerated to speeds of up to 4.2 km/s. Also, repetitive operation of the two-stage gun (four plastic pellets fired at {approx}0.5 Hz) was demonstrated for the first time in preliminary tests. The equipment …
Date: January 1, 1989
Creator: Combs, S. K.; Foust, C. R.; Gouge, M. J. & Milora, S. L.
System: The UNT Digital Library
Accelerator diagnosis and control by Neural Nets (open access)

Accelerator diagnosis and control by Neural Nets

Neural Nets (NN) have been described as a solution looking for a problem. In the last conference, Artificial Intelligence (AI) was considered in the accelerator context. While good for local surveillance and control, its use for large complex systems (LCS) was much more restricted. By contrast, NN provide a good metaphor for LCS. It can be argued that they are logically equivalent to multi-loop feedback/forward control of faulty systems, and therefore provide an ideal adaptive control system. Thus, where AI may be good for maintaining a 'golden orbit,' NN should be good for obtaining it via a quantitative approach to 'look and adjust' methods like operator tweaking which use pattern recognition to deal with hardware and software limitations, inaccuracies or errors as well as imprecise knowledge or understanding of effects like annealing and hysteresis. Further, insights from NN allow one to define feasibility conditions for LCS in terms of design constraints and tolerances. Hardware and software implications are discussed and several LCS of current interest are compared and contrasted. 15 refs., 5 figs.
Date: January 1, 1989
Creator: Spencer, J.E.
System: The UNT Digital Library
Accelerator for the production of tritium (APT) (open access)

Accelerator for the production of tritium (APT)

A collaborative study by Los Alamos and Brookhaven National Laboratories, supported by the Westinghouse Hanford Company, investigating a facility to produce tritium for the nation's defense needs indicates that a 1.6-GeV, 250-mA proton accelerator is required. A reference design of this accelerator starts with two parallel 125-keV injectors feeding 350-MHz radio-frequency quadrupoles (RFQ) that funnel at 2.5 MeV into a 700-MHz drift-tube linac (DTL). The DTL injects at 100 MeV into a 1400-MHz side-coupled linac (SCL). The accelerator will cost about $1.2 B and require 746 MW of electricity. 3 refs., 3 tabs.
Date: January 1, 1989
Creator: Wilson, M. T.; Bhatia, T. S.; Guy, F. W.; Neuschaefer, G. H.; Wangler, T. P. & Young, L. M.
System: The UNT Digital Library
Achieving Consensus in Environmental Programs (open access)

Achieving Consensus in Environmental Programs

In this paper, we describe a new research effort on consensus tied to the Environmental Restoration Program (ERP) within the US Department of Energy's Office of Defense Waste and Transportation Management (DWTM). We define consensus and explain why consensus decisions are not merely desirable but necessary in furthering ERP activities. As examples of our planned applied research, we first discuss Nominal Group Technique as a representative consensus-generating tool, and we conclude by describing the consensus-related mission of the Waste Management Review Group, established at Virginia Tech to conduct independent, third-party review of DWTM/ERP plans and activities. 10 refs.
Date: January 1, 1989
Creator: Kurstedt, Jr., H. A.; Jones, R. M.; Walker, J. A. & Middleman, L. I.
System: The UNT Digital Library
Actinide recycle potential in the IFR (Integral Fast Reactor) (open access)

Actinide recycle potential in the IFR (Integral Fast Reactor)

Rising concern about the greenhouse effect reinforces the need to reexamine the question of a next-generation reactor concept that can contribute significantly toward substitution for fossil-based energy generation. Even with only the nuclear capacity on-line today, world-wide reasonably assured uranium resources would last for only about 50 years. If nuclear is to make a significant contribution, breeding is a fundamental requirement. Uranium resources can then be extended by two orders of magnitude, making nuclear essentially a renewable energy source. The key technical elements of the IFR concept are metallic fuel and fuel cycle technology based on pyroprocessing. Pyroprocessing is radically different from the conventional PUREX reprocessing developed for the LWR oxide fuel. Chemical feasibility of pyroprocessing has been demonstrated. The next major step in the IFR development program will be the full-scale pyroprocessing demonstration to be carried out in conjunction with EBR-II. IFR fuel cycle closure based on pyroprocessing can also have a dramatic impact on the waste management options, and in particular on the actinide recycling. 6 figs.
Date: January 1, 1989
Creator: Chang, Y. I.
System: The UNT Digital Library
Active interlock for storage ring insertion devices (open access)

Active interlock for storage ring insertion devices

The insertion devices in the NSLS x-ray ring produce such intense photon beams that passive measures alone are not adequate to protect the vacuum chamber. An active interlock is used to prevent thermal damage from improperly steered electron beams. The interlock system measures the position of the electron beam on both sides of the insertion devices using pick-up electrodes and interrupts the rf if the beam moves outside a safe window. The interlock features redundant circuitry as well as an automatic testing procedure. 1 ref., 4 figs.
Date: January 1, 1989
Creator: Rochman, J. L. & Nawrocky, R. J.
System: The UNT Digital Library
Adaptive enhancement of magnetoencephalographic signals via multichannel filtering (open access)

Adaptive enhancement of magnetoencephalographic signals via multichannel filtering

A time-varying spatial/temporal filter for enhancing multichannel magnetoencephalographic (MEG) recordings of evoked responses is described. This filter is based in projections derived from a combination of measured data and a priori models of the expected response. It produces estimates of the evoked fields in single trial measurements. These estimates can reduce the need for signal averaging in some situations. The filter uses the a priori model information to enhance responses where they exist, but avoids creating responses that do not exist. Examples are included of the filter's application to both MEG single trial data containing an auditory evoked field and control data with no evoked field. 5 refs., 7 figs.
Date: January 1, 1989
Creator: Lewis, P.S.
System: The UNT Digital Library
Additional capabilities and benchmarking with the SPERT transients for heavy water application of the PARET code (open access)

Additional capabilities and benchmarking with the SPERT transients for heavy water application of the PARET code

The capabilities of the PARET code have been expanded to include the ability to compute steady-state and transient results for heavy water reactors. A comparison is provided between PARET and the SPERT II series of transients. Another significant improvement in the code is the addition of a restart capability. The current capabilities of the code are summarized. 7 refs., 12 figs., 3 tabs.
Date: January 1, 1989
Creator: Woodruff, W.L.
System: The UNT Digital Library
Advanced Accelerator Test Facility (AATF) Upgrade Plan (open access)

Advanced Accelerator Test Facility (AATF) Upgrade Plan

We have successfully demonstrated the principles of wake-field acceleration using structures (cavity, dielectric) and plasmas as wake-field devices using the AATF at Argonne National Laboratory. Due to the limited driver electron pulse intensity and relative long pulse length, only modest accelerating gradients were observed. In order to study the wake field effects in much greater detail and demonstrate the feasibility of wake-field accelerator for high energy physics, we are considering construction of a laser photocathode injector on the existing 20 MeV Chem-Linac to produce very intense and short electron pulses. 10 refs., 5 figs.
Date: January 1, 1989
Creator: Gai, W.; Ho, C.; Konecny, R.; Mtingwa, S.; Norem, J.; Rosenzweig, J. et al.
System: The UNT Digital Library
Advanced binary geothermal power plants working fluid property determination and heat exchanger design (open access)

Advanced binary geothermal power plants working fluid property determination and heat exchanger design

The performance of binary geothermal power plants can be improved through the proper choice of a working fluid, and optimization of component designs and operating conditions. This paper reviews the investigations at the Idaho National Engineering Laboratory (INEL) which are examining binary cycle performance improvements for moderate temperature (350 to 400 F) resources with emphasis on how the improvements may be integrated into design of binary cycles. These investigations are examining performance improvements resulting from the supercritical vaporization of mixed hydrocarbon working fluids and achieving countercurrent integral condensation with these fluids, as well as the modification of the turbine inlet state points to achieve supersaturated turbine vapor expansions. For resources where the brine outlet temperature is restricted, the use of turbine exhaust recuperators is examined. The baseline plant used to determine improvements in plant performance (characterized by the increase in the net brine effectiveness, watt-hours per pound of brine) in these studies operates at conditions similar to the 45 MW Heber binary plant. Through the selection of the optimum working fluids and operating conditions, achieving countercurrent integral condensation, and allowing supersaturated vapor expansions in the turbine, the performance of the binary cycle (the net brine effectiveness) can be improved by …
Date: January 1, 1989
Creator: Bliem, C.J. & Mines, G.L.
System: The UNT Digital Library
Advanced composite materials and processes for the manufacture of SSC (Superconducting Super Collider) and RHIC (Relativistic Heavy Ion Collider) superconducting magnets used at cryogenic temperatures in a high radiation environment (open access)

Advanced composite materials and processes for the manufacture of SSC (Superconducting Super Collider) and RHIC (Relativistic Heavy Ion Collider) superconducting magnets used at cryogenic temperatures in a high radiation environment

Presently, BNL work on superconducting magnets centers mainly on the development of 17 meter length dipoles for the Superconducting Super Collider Project, approved for construction at Waxahatchie, Texas and 9.7 meter dipoles and quadrupoles for the Relativistic Heavy Ion Collider, a BNL project to start construction next year. This paper will discuss the role of composites in the manufacture of magnets, their operational requirements in cryogenic and radiation environments, and the benefits derived from their use. 13 figs.
Date: January 1, 1989
Creator: Sondericker, J.H.
System: The UNT Digital Library
The Advanced Composition Explorer (open access)

The Advanced Composition Explorer

The Advanced Composition Explorer (ACE) was recently selected as one of two new Explorer-class missions to be developed for launch during the mid-1990's. ACE will observe particles of solar, interplanetary, interstellar, and galactic origins, spanning the energy range from that of the solar wind ({approximately}1 keV/nucleon) to galactic cosmic ray energies (several hundred MeV/nucleon). Definitive studies will be made of the abundance of nearly all isotopes from H to Zn (1{le}Z{le}30), with exploratory isotope studies extending to Zr (Z = 40). To accomplish this, the ACE payload includes six high-resolution spectrometers, each designed to provide the optimum charge, mass, or charge-state resolution in its particular energy range, and each having a geometry factor optimized for the expected flux levels, so as to provide a collecting power a factor of 10 to 1000 times greater than previous or planned experiments. The payload also includes several instruments of standard design that will monitor solar wind and magnetic field conditions and energetic H, He, and electron fluxes. We summarize here the scientific objectives, instrumentation, spacecraft, and mission approach that were defined for ACE during the Phase-A study period. 4 refs., 4 figs., 2 tabs.
Date: January 1, 1989
Creator: Stone, E. C.; Cummings, A. C.; Mewaldt, R. A. (California Inst. of Tech., Pasadena, CA (USA)); Burlaga, L. F.; Rosenvinge, T. T. von (National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center); Feldman, W. C. et al.
System: The UNT Digital Library
Advanced Hydride Laboratory (open access)

Advanced Hydride Laboratory

Metal hydrides have been used at the Savannah River Tritium Facilities since 1984. However, the most extensive application of metal hydride technology at the Savannah River Site is being planned for the Replacement Tritium Facility, a $140 million facility schedules for completion in 1990 and startup in 1991. In the new facility, metal hydride technology will be used to store, separate, isotopically purify, pump, and compress hydrogen isotopes. In support of the Replacement Tritium Facility, a $3.2 million, cold,'' process demonstration facility, the Advanced Hydride Laboratory began operation in November of 1987. The purpose of the Advanced Hydride Laboratory is to demonstrate the Replacement Tritium Facility's metal hydride technology by integrating the various unit operations into an overall process. This paper will describe the Advanced Hydride Laboratory, its role and its impact on the application of metal hydride technology to tritium handling.
Date: January 1, 1989
Creator: Motyka, T.
System: The UNT Digital Library