Simulation of the carbon cycle in the ocean (open access)

Simulation of the carbon cycle in the ocean

A dual carbon-nitrogen biological model of the upper ocean has been developed, which has successfully allowed predictions of fluxes of carbon between atmosphere and the deep ocean to made. Regarding studying the carbon cycle in the ocean, the modelling has highlighted the need for a good understanding of the interactions between the carbon and nitrogen cycles, and also the importance of zooplankton grazing and levels of overwintering biological stocks. Problems have been encountered with the accuracy of prediction of the partial pressure of carbon dioxide in the surface ocean, and the sensitivity of the model to zooplankton parameters, and those parameters which effect overwintering stocks (e.g. mortality parameters). The model has recently been incorporated into a physical General Circulation Model of the Atlantic Ocean. Future work will involve assessing the performance of the biological model in General Circulation Models, and making necessary refinements in order to improve its predictive ability. 1 ref., 1 fig.
Date: September 16, 1991
Creator: Fasham, M.J.R.
Object Type: Report
System: The UNT Digital Library
An IFE development strategy (open access)

An IFE development strategy

The development of inertial fusion as a power source will require achieving four principal milestones: ignition and propagating burn; high gain at low drive energy for the reactor driver; pulse repetition rates of a few Hz; and long-term reliability and economics of a reactor. To keep development time and costs to a minimum, these should be accomplished with as few major facilities as possible. A viable scenario for the Inertial Fusion Energy (IFE) Program would include establishing the first milestone in a Nova Upgrade for ignition and gain and the latter three in an upgradable, low-power Engineering Test Facility (ETF)/Demonstration Power Plant (DPP), i.e. two major facilities. To be successful in as short a time as possible operations at the major facilities would have to be supported by off-line reactor driver and other reactor technology development efforts. These efforts would evaluate and prioritize the myriad of options available at present for power plant and subsystem concepts. This paper describes the elements of such a program that could make the first commercial power available in the decade of the 2020s and estimates the resources needed. This program would be carried out in phases with major go/no-go decision points before each large …
Date: July 16, 1991
Creator: Hogan, W.J.; Storm, E. & Lindl, J.D.
Object Type: Article
System: The UNT Digital Library
Budgets and behaviors of uranium and thorium series isotopes in the Santa Monica Basin off the California Coast (open access)

Budgets and behaviors of uranium and thorium series isotopes in the Santa Monica Basin off the California Coast

Samples from three time-series sediment traps deployed in the Santa Monica Basin off the California coast were analyzed to study the flux and scavenging of uranium and thorium series isotopes. Variations of uranium and thorium series isotopes fluxes in the water column were obtained by integrating these time-series deployment results. Mass and radionuclide fluxes measured from bottom sediment traps compare favorably with fluxed determined from sediment core data. This agreement suggests that the near-bottom sediment traps are capable of collecting settling particles representative of the surface sediment. The phase distributions of {sup 234}Th in the water column were calculated by an inverse method using sediment trap data, which help to study the variations of {sup 234}Th scavenging in the water column. Scavenging and radioactive decay of {sup 234}Th are the two principal processes for balancing {sup 234}Th budget in the water column. The residence times of dissolved and particulate {sup 234}Th were determined by a {sup 234}Th scavenging model.
Date: December 16, 1991
Creator: Yu, Lei.
Object Type: Report
System: The UNT Digital Library
Baryon inhomogeneity from the cosmic quark-hadron phase transition (open access)

Baryon inhomogeneity from the cosmic quark-hadron phase transition

We discuss the generation of inhomogeneity in the baryon-number density during the cosmic quark-hadron phase transition. We use a simple model with thin-wall phase boundaries and ideal-gas equations of state. The nucleation of the phase transition introduces a new distance scale into the universe which will be the scale of the generated inhomogeneity. We review the estimate of this scale. During the transition baryon number is likely to collect onto a layer at the phase boundary. These layers may in the end be deposited as small regions of very high baryon density. 21 refs., 1 fig.
Date: July 16, 1991
Creator: Kurki-Suonio, H.
Object Type: Article
System: The UNT Digital Library
Soft x-ray measurement of internal tearing mode structure in a reversed-field pinch (open access)

Soft x-ray measurement of internal tearing mode structure in a reversed-field pinch

The structure of internally resonant tearing modes has been studied in the Madison Symmetric Torus reversed-field pinch with a soft x-ray detector system consisting of an imaging array at one toroidal location and several detectors at different toroidal locations. The toroidal mode numbers of m = 1 structures are in the range n = {minus}5, {minus}6, {minus}7. The modes propagate with phase velocity v = 1--6 {times} 10{sup 6} cm/s, larger than the diamagnetic drift velocity v{sub d} {approximately} 5 {times} 10{sup 5} cm/s. Phase locking between modes with different n in manifested as a beating of soft x-ray signals which is found to be strongest near the resonant surfaces of the modes (r/a = 0.1 -- 0.5). 15 refs., 5 figs.
Date: September 16, 1991
Creator: Chartas, G. & Hokin, S.
Object Type: Report
System: The UNT Digital Library
International workshop of chromosome 19 (open access)

International workshop of chromosome 19

This document summarizes the workshop on physical and genetic mapping of chromosome 19. The first session discussed the major disease loci found on the chromosome. The second session concentrated on reference families, markers and linkage maps. The third session concentrated on radiation hybrid mapping, somatic cell hybrid panels, macro restriction maps and YACs, followed by cDNA and long range physical maps. The fourth session concentrated on compiling consensus genetic and physical maps as well as discussing regions of conflict. The final session dealt with the LLNL cosmid contig database and comparative mapping of homologous regions of the human and mouse genomes, and ended with a discussion of resource sharing. 18 refs., 2 figs. (MHB)
Date: September 16, 1991
Creator: Pericak-Vance, M.A. (Duke Univ. Medical Center, Durham, NC (United States). Div. of Neurology) & Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))
Object Type: Article
System: The UNT Digital Library
Prototype SDC Muon alignment-position monitoring concepts (open access)

Prototype SDC Muon alignment-position monitoring concepts

We have developed and tested some prototype ideas, components, and systems for monitoring the relative planar orientations, spacings between, transverse positions and rotations of the multi Muon supermodule layers in a given SDC Muon chamber projective tower. These are described and parameterized from measurements. Their resolutions are given, and long term stabilities have been determined.
Date: March 16, 1991
Creator: Eartly, D. & Johnson, P.
Object Type: Report
System: The UNT Digital Library
Neutron capture therapy: Years of experimentation---Years of reflection (open access)

Neutron capture therapy: Years of experimentation---Years of reflection

This report describes early research on neutron capture therapy over a number of years, beginning in 1950, speaking briefly of patient treatments but dwelling mostly on interpretations of our animal experiments. This work carried out over eighteen years, beginning over forty years ago. Yet, it is only fitting to start by relating how neutron capture therapy became part of Brookhaven's Medical Research Center program.
Date: December 16, 1991
Creator: Farr, L.E.
Object Type: Report
System: The UNT Digital Library
Chamber propagation (open access)

Chamber propagation

Propagation of a heavy ion beam to the target appears possible under conditions thought to be realizable by several reactor designs. Beam quality at the lens is believed to provide adequate intensity at the target -- but the beam must pass through chamber debris and its self fields along the way. This paper reviews present consensus on propagation modes and presents recent results on the effects of photoionization of the beam ions by thermal x-rays from the heated target. Ballistic propagation through very low densities is a conservative mode. The more-speculative self-pinched mode, at 1 to 10 Torr, offers reactor advantages and is being re-examined by others. 13 refs.
Date: January 16, 1991
Creator: Langdon, B.
Object Type: Article
System: The UNT Digital Library
Chiral symmetry breaking in gauge theories from Reggeon diagram analysis (open access)

Chiral symmetry breaking in gauge theories from Reggeon diagram analysis

It is argued that reggeon diagrams can be used to study dynamical properties of gauge theories containing a large number of massless fermions. SU(2) gauge theory is studied in detail and it is argued that there is a high energy solution which is analogous to the solution of the massless Schwinger model. A generalized winding-number condensate produces the massless pseudoscalar spectrum associated with chiral symmetry breaking and a trivial'' S-Matrix.
Date: December 16, 1991
Creator: White, A. R.
Object Type: Article
System: The UNT Digital Library
The equation of state of liquid Flibe (open access)

The equation of state of liquid Flibe

Flibe (Li{sub 2}BeF{sub 4}) is a candidate material for the liquid blanket in the HYLIFE-2 fusion reactor. The thermodynamic properties of the material are important for the study of thermohydraulic behavior of the concept design, including the compressible analysis of the blanket isochoric heating problem and resulting jet breakup. The equation of state provides the relationship between all the thermodynamic properties. Previously, a soft sphere model of liquid equation of state was used for describing a number of liquid metals. In this paper we have fitted the available experimental data for liquid Flibe with a modified soft sphere model. 5 refs.
Date: August 16, 1991
Creator: Chen, Xiang M.; Schrock, V.E. & Peterson, P.F.
Object Type: Article
System: The UNT Digital Library
Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties (open access)

Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties

The current knowledge is reviewed on (1) the effects of neutron irradiation on tensile strength and ductility, ductile-brittle transition temperature, creep, fatigue, and swelling of vanadium-base alloys, (2) the compatibility of vanadium-base alloys with liquid lithium, water, and helium environments, and (3) the effects of hydrogen and helium on the physical and mechanical properties of vanadium alloys that are potential candidates for structural materials applications in fusion systems. Also, physical and mechanical properties issues are identified that have not been adequately investigated in order to qualify a vanadium-base alloy for the structural material in experimental fusion devices and/or in fusion reactors.
Date: December 16, 1991
Creator: Loomis, B. A. & Smith, D. L.
Object Type: Article
System: The UNT Digital Library
A study of potential high band-gap photovoltaic materials for a two step photon intermediate technique in fission energy conversion (open access)

A study of potential high band-gap photovoltaic materials for a two step photon intermediate technique in fission energy conversion

A diamond synthesis chamber and an ion implanter have been constructed. Work has been rapidly progressing and diamond has been synthesized. There are five variables which affect the quality of diamond: (1) mass flow of methane, (2) mass flow of hydrogen, (3) filament temperature, (4) substrate temperature, and (5) substrate material. Enclosed are pictures and data of previous diamond growth experiments. Current work is focused on the conditions which produce the best quality diamond films. In this study, diamond films were deposited using a hot-filament CVD method with boron trioxide (B{sub 2}O{sub 3}) and diphosphorus pentoxide (P{sub 2}O{sub 5}) as the doping sources. P{sub 2}O{sub 5} is the only known effective phosphorus source for forming n-type semiconducting material. An RF generator has been made operation for epitaxial growth of AIN by the chemical vapor deposition method. In initial experiments with a graphite substrate, the RF generator heated the material to a temperature of 1100{degrees}C. A reactor which will use the RF generator has been built for AIN synthesis. The device should be assembled and tested by the end of August. A new process for fabricating platinum silicide photovoltaic cells has been developed. A diffused guard ring has been added to …
Date: August 16, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
LIMB demonstration project extension (open access)

LIMB demonstration project extension

The main objectives of this project are: (1) To demonstrate the general applicability of Limestone Injection Multistage Burner (LIMB) technology by testing 3 coals and 4 sorbents (total of 12 coal/sorbent combinations) at the Ohio Edison Edgewater Plant. (2) To demonstrate that Coolside is a viable technology for improving precipitator performance and reducing sulfur dioxide emissions while acceptance operability is maintained. During the past quarter, activities for phase I, design and permitting, and phase II, construction, shakedown and start-up were completed for phase III, operation, data collection, reporting and disposition, activities continued with consol completing the revisions to the Coolside Topical report, the completion of LIMB Extension testing, and the start of demobilization and restoration.
Date: December 16, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Steam gasification of carbon: Catalyst properties (open access)

Steam gasification of carbon: Catalyst properties

This research uses several techniques to measure the concentration of catalyst sites and determine their stoichiometry for the catalyzed gasification of carbon. Both alkali and alkaline earth oxides are effective catalysts for accelerating the gasification rate of coal chars, but only a fraction of the catalyst appears to be in a form that is effective for gasification, and the composition of that catalyst is not established. Transient techniques, with {sup 13}C labeling, are being used to study the surface processes, to measure the concentration of active sites, and to determine the specific reaction rates. We have used secondary ion mass spectroscopy (SIMS) for both high surface area samples of carbon/alkali carbonate mixtures and for model carbon surfaces with deposited alkali atoms. SIMS provides a direct measure of surface combination of these results can provide knowledge of catalyst dispersion and composition, and thus indicate the way to optimally utilize carbon gasification catalysts.
Date: September 16, 1991
Creator: Falconer, J.L.
Object Type: Report
System: The UNT Digital Library
Enzymatic desulfurization of coal (open access)

Enzymatic desulfurization of coal

The overall objective of this program was to investigate the feasibility of an enzymatic desulfurization process specifically intended for organic sulfur removal from coal. Toward that end, a series of specific objectives were defined: (1) establish the feasibility of (bio)oxidative pretreatment followed by biochemical sulfate cleavage for representative sulfur-containing model compounds and coals using commercially-available enzymes; (2) investigate the potential for the isolation and selective use of enzyme preparations from coal-utilizing microbial systems for desulfurization of sulfur-containing model compounds and coals; and (3) develop a conceptual design and economic analysis of a process for enzymatic removal of organic sulfur from coal. Within the scope of this program, it was proposed to carry out a portion of each of these efforts concurrently. (VC)
Date: May 16, 1991
Creator: Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P. & Nochur, S.V.
Object Type: Report
System: The UNT Digital Library
Electroweak phase transitions (open access)

Electroweak phase transitions

An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l angle}{phi}{r angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l angle}{phi}{r angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l angle}{phi}{r angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l angle}{phi}{r angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l angle}{phi}{r angle} = 246 GeV unstable. The requirement that the state …
Date: September 16, 1991
Creator: Anderson, G.W.
Object Type: Report
System: The UNT Digital Library
The analysis of the Flibe jets in HYLIFE-II (open access)

The analysis of the Flibe jets in HYLIFE-II

In the HYLIFE-2 Inertial Confinement Fusion reactor, an array of Flibe (Li{sub 2}BeFe{sub 4}) jets is designed to protect the chamber from the fusion radiation. During the fusion pulse the Flibe jets sustain an instantaneous neutron and X-ray heating. The high energy neutrons from fusion can penetrate deep into the Flibe jets and the sudden increase in internal energy can induce a great pressure rise inside the jets. The subsequent relaxation of the jets is important for the reactor design, because the configuration of the jets will control the subsequent impact forces of vapor and liquid on the reactor chamber wall. The calculations for the lithium jets in the HYLIFE-1 reactor were done previously by using a compressible flow model with a soft sphere equation of state for lithium. A similar equation of state model for Flibe was recently developed. This model allows us to use the same compressible analysis code to calculate the pressure field in the Flibe jets and to estimate the upper bound of the Flibe tension limit. With these results we can analyze the mechanisms of jet relaxation and breakup. 4 refs., 1 fig.
Date: August 16, 1991
Creator: Chen, Xiang M.; Schrock, V.E. & Peterson, P.F.
Object Type: Article
System: The UNT Digital Library
(Attendance at the XIV Nuclear Physics Symposium) (open access)

(Attendance at the XIV Nuclear Physics Symposium)

This report includes background material on the long-standing series of annual symposia presented by the Mexican nuclear physics community, summarizes the highlights of the fourteenth symposium in the series, and records items learned by the traveler in subsequent visits to two research laboratories in Mexico.
Date: January 16, 1991
Creator: Halbert, M.L.
Object Type: Report
System: The UNT Digital Library
Analysis of time- and space-resolved Na-, Ne-, and F-like emission from a laser-produced bromine plasma (open access)

Analysis of time- and space-resolved Na-, Ne-, and F-like emission from a laser-produced bromine plasma

Advances in the efficiency and accuracy of computational atomic physics and collisional radiative modeling promise to place the analysis and diagnostic application of L-shell emission on a par with the simpler K-shell regime. Coincident improvements in spectroscopic plasma measurements yield optically thin emission spectra from small, homogeneous regions of plasma, localized both in space and time. Together, these developments can severely test models for high-density, high-temperature plasma formation and evolution, and non-LTE atomic kinetics. In this paper we present highly resolved measurements of n=3 to n=2 X-ray line emission from a laser-produced bromine micro-dot plasma. The emission is both space- and time-resolved, allowing us to apply simple, steady-state, 0-dimensional spectroscopic models to the analysis. These relativistic, multi-configurational, distorted wave collisional-radiative models were created using the HULLAC atomic physics package. Using these models, we have analyzed the F-like, Ne-like and Na-like (satellite) spectra with respect to temperature, density and charge-state distribution. This procedure leads to a full characterization of the plasma conditions. 9 refs., 3 figs.
Date: January 16, 1991
Creator: Goldstein, W.H.; Young, B.K.F.; Osterheld, A.L.; Stewart, R.E.; Walling, R.S. (Lawrence Livermore National Lab., CA (USA)); Bar-Shalom, A. (Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev) et al.
Object Type: Article
System: The UNT Digital Library
Agenda and briefing book: Clean Coal Technology Coordinating Committee, September 16, 1991, Louisville, Kentucky (open access)

Agenda and briefing book: Clean Coal Technology Coordinating Committee, September 16, 1991, Louisville, Kentucky

A considerable amount of time was spent discussing the Clean Air Act Amendments pending before Congress. Several members pointed out provisions of the legislation that would have serious impacts on the coal industry and the electric utility industry. The need for increased electricity in Florida raised the question about coal fired Power Plants. It is generally believed that most people in Florida do not know that over 55 percent of the electricity now comes from coal-fired generators. However, publicly, people will say they do not want coal-fired facilities built in Florida. People in Florida are concerned with the EMF Issue just as much as the source of power. It was stated that the coal industry has a very poor image and DOE should assume responsibility for improving the image of coal. it was agreed that it would take a considerable financial commitment to do this and that in addition to government the industry would have to be willing to contribute financially. The Partial results of a survey to utilities concerning the future use of clean coal technologies was reported. Utilities are not ignoring coal technologies but acknowledged that the amendments to the Clean Air Act would be the driving force …
Date: September 16, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 16, Number 53, Pages 3915-3965, July 16, 1991 (open access)

Texas Register, Volume 16, Number 53, Pages 3915-3965, July 16, 1991

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: July 16, 1991
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Register, Volume 16, Number 29, Pages 2121-2247, April 16, 1991 (open access)

Texas Register, Volume 16, Number 29, Pages 2121-2247, April 16, 1991

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: April 16, 1991
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Texas Register, Volume 16, Number 61, Pages 4429-4516, August 16, 1991 (open access)

Texas Register, Volume 16, Number 61, Pages 4429-4516, August 16, 1991

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: August 16, 1991
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History