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(open access)

Feasibility Study of a New Mass Flow System. Quarterly Report No. 5, June 1, 1961 to August 31, 1961

Activities are reported on development work on a mass flow system capable of measuring externally the properties of homogeneous flow, slurries, highly corrosive fluids, and multi-phase fiuids. In the proposed system, the fluid passes through an S-shaped tube wherein measurements of angular momentum and density yield mass flow directly. (B.O.G.)

Date: September 20, 1961

Creator: Haffner, J. W.

Object Type: Report

System: The UNT Digital Library

(open access)

Advective-diffusive/dispersive transport of chemically reacting species in hydrothermal systems. Final report, FY83-85

A general formulation of multi-phase fluid flow coupled to chemical reactions was developed based on a continuum description of porous media. A preliminary version of the computer code MCCTM was constructed which implemented the general equations for a single phase fluid. The computer code MCCTM incorporates mass transport by advection-diffusion/dispersion in a one-dimensional porous medium coupled to reversible and irreversible, homogeneous and heterogeneous chemical reactions. These reactions include aqueous complexing, oxidation/reduction reactions, ion exchange, and hydrolysis reactions of stoichiometric minerals. The code MCCTM uses a fully implicit finite difference algorithm. The code was tested against analytical calculations. Applications of the code included investigation of the propagation of sharp chemical reaction fronts, metasomatic alteration of microcline at elevated temperatures and pressures, and ion-exchange in a porous column. Finally numerical calculations describing fluid flow in crystalline rock in the presence of a temperature gradient were compared with experimental results for quartzite.

Date: June 20, 1986

Creator: Lichtner, P. C. & Helgeson, H. C.

Object Type: Report

System: The UNT Digital Library

(open access)

Strontium, Strontium-90, and Calcium Analyses of Clinch and Tennessee River Clams

Analyses of clam shells for Sr, Sr/sup 90/, and Ca are reported. The data include 208 Sr, 80 Sr/sup 90/, and 35 Ca analyses. Information on age of the clam and shell weight are also included because the Sr concentration in some shells is affected by age and growth rate. A detailed description of sample treatment and preparation is also included. (auth)

Date: June 20, 1962

Creator: Nelson, D. J.

Object Type: Report

System: The UNT Digital Library

(open access)

Why search for double beta decay

Searching for neutrinoless double beta decay is the only known practical method for trying to determine whether neutrinos are their own antiparticles. The theoretical motivation for supposing that they may indeed be their own antiparticles is described. The reason that it is so difficult to ascertain experimentally whether they are or are not is explained, as is the special sensitivity of neutrinoless double beta decay. The potential implications of the observation of this reaction for neutrino mass and for the physics of neutrinos is discussed.

Date: April 20, 1988

Creator: Kayser, B.

Object Type: Article

System: The UNT Digital Library

(open access)

Automatic beam centering at the SSC interaction regions

In the SSC interaction regions, the two colliding beams, each only a few microns in size, will have to be centered and maintained in good alignment over many hours, in order to provide the maximum possible luminosity and to minimize off-center beam-beam focussing effects. It is unlikely that sufficiently good alignment can be achieved without some kind of active feedback system, based on the beam-beam interaction rate. This memo describes such a system. In the proposed scheme, one of the beams is moved continuously and in a circular fashion about its mean transverse position. The radius of this motion is approximately 0.01 of the rms beam size at the interaction point. The motion is achieved with two sets of crossed high frequency dipole magnets, one on each side of the interaction region, suitably phased. As a consequence of this motion, the beam-beam interaction rate is modulated in synchronism with the beam motion when the beams are not centered on one another. The amplitude and phase of this modulation yields information on the magnitude and direction of the misalignment between the beams, allowing continuous display and automatic correction of any misalignment.

Date: March 20, 1984

Creator: Joestlein, H.

Object Type: Report

System: The UNT Digital Library

(open access)

BX in situ oil shale project. Quarterly technical progress report, September 1-November 30, 1981

September 1, 1981-November 30, 1981, was the fourth consecutive quarter of superheated steam injection at the BX In Situ Oil Shale Project. During the quarter, 117,520 barrels of water as steam were injected into project injection wells at an average wellhead temperature of 715/sup 0/F and an average wellhead pressure of 1378 PSIG. During the same period, 148,516 barrels of fluid were produced from the project production wells for a produced-to-injected fluid ratio of 1.26 to 1.0. Net oil production for the quarter was 169 barrels.

Date: December 20, 1981

Creator: Dougan, P. M.

Object Type: Report

System: The UNT Digital Library

(open access)

Laser produced plasma soft x-ray generation

The efficiency of soft x-ray production from laser-irradiated plasmas is simulated for two different spectral regions. These two regions, 14{Angstrom} {plus minus} 15% and 130{Angstrom} {plus minus} 1%, were chosen for proximity mask or point-projection technological applications. Relatively large conversion efficiencies were obtained from irradiation of a stainless steel target using the conditions suggested by recent Hampshire Instruments' experiments for proximity masking. Pulse-width and laser frequency parameter studies were performed for point-projection applications which suggest that the conversion applications which suggest that the conversion efficiency is sensitive to pulse-width but not to laser frequency. One of the critical components of any x-ray lithographic scheme is of course the x-ray laser source. There are two primary contenders for a reliable, efficient source currently: synchrotron radiation and spectral emission from laser produced plasma. The dominant issue for laser-plasma emission is the conversion efficiency -- output in the intended operating spectral region relative the required incident laser energy. Simulations are described in the following for both high and low energy spectral regions which have been suggested by either the proximity masking or point-projection technology.

Date: May 20, 1991

Creator: Cerjan, C. & Rosen, M.D.

Object Type: Article

System: The UNT Digital Library

(open access)

Applications of Micellar Enzymology to Clean Coal Technology

This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid Dibenzothiophene (DBT) and ehtylphenylsulfide (EPS)are serving as serving as models of organic sulfur-containing components of coal in initial studies.

Date: January 20, 1990

Creator: Walsh, C. T.

Object Type: Report

System: The UNT Digital Library

(open access)

Directions for possible upgrades of the Mirror Fusion Test Facility (MFTF)

The Mirror Fusion Test Facility (MFTF) may be upgraded by extending the time of plasma sustenance in an approach to steady-state operation and/or by increasing the neutral-beam injection energy. Some parameter bounds for these upgrades are discussed as they relate to a definition of the required neutral-beam development.

Date: December 20, 1977

Creator: Damm, C. C.; Coensgen, F. H.; Devoto, R. S.; Molvik, A. W.; Porter, G. D.; Shearer, J. W. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Elementary reaction rate measurements at high temperatures by tunable-laser flash-absorption

The major objective of this program is to measure thermal rate coefficients and branching ratios of elementary reactions. To perform these measurements, we have constructed an ultrahigh-purity shock tube to generate temperatures between 1000 and 5500 K. The tunable-laser flash-absorption technique is used to measure the rate of change of the concentration of species which absorb below 50,000 cm{sup {minus}1} e.g.: OH, CH, and CH{sub 3}. This technique is being extended into the vacuum-ultraviolet spectral region where we can measure atomic species e.g.: H, D, C, O, and N; and diatomic species e.g.: O{sub 2}, CO, and OH.

Date: March 20, 1992

Creator: Hessler, J.P.

Object Type: Article

System: The UNT Digital Library

(open access)

Plutonium Residue Recovery (PuRR) project quarterly progress report, April--June 1989

A material-balance flowsheet for ash-heel processing has been prepared. The major process features are (1) reduction of Pu into a calcium-zinc alloy and selective electrolytic recovery of the Pu from the alloy, (2) removal of americium as a waste, (3) concentration of nontransuranic tramp elements in a zinc waste, (4) removal of oxygen and recovery of calcium by electrolysis of CaO, and (5) zinc recycle by evaporation. Based on this idealized flowsheet, the mass of solid waste is only 62% of that of the original residue. This is accomplished by recycling virtually all the reagents and discarding the oxygen as CO and CO{sub 2}. The pyrochemical recovery of Pu from incinerator ash heel from the Rocky Flats Plant was investigated. During this period, zinc-calcium alloys were used to reduce the PuC{sub 2} in the ash. Reduction of ash heel has been attempted with zinc-calcium alloys containing 2, 6, and 10 wt% calcium after the reduction. These resulted in extractions of 95%, 97%, and 99.5%, respectively, of the Pu from the salt. Following exposure of the reduction alloy to a ZnCl{sub 2}-bearing salt, the Pu was removed effectively from the alloy; however, the Pu recovered in the salt did not complete …

Date: October 20, 1989

Creator: Gregg, D. W.; Hickman, R. G.; Landrum, J. H. (Lawrence Livermore National Lab., CA (USA)); Johnson, G. K.; Johnson, I.; Mulcahey, T. P. et al.

Object Type: Report

System: The UNT Digital Library

(open access)

Ecological Sampling and Meteorological Calculation of Fallout on Forests Near Oak Ridge

Spatial patterns of radioactive contuamination on forest foliage were measured by gamma spectrometry and are discussed with respect to local vs. world- wide origin of the fallout and implications for ecology, health physics, and management of nuclear facilities. In September 1959, I/sup 131/ on dogwood leaf samples varied from over 500 mu mu c/g dry wt near Oak Ridge National Laboratory stacks to 1 to 7 mu mu c/g near the margins of the Oak Ridge Reservation. Stack fallout tended to occur closer to the source than was calculated from hourly wind data by an IBM 610 computer program based on Culkowski' s adaptation of the SuttonChamberlain theory of atmospheric diffusion and deposition. Over most of the Reservation levels of Ru/sup 106/ Cs/sup 137/ Zr/sup 9/ >s/sup 5/Nb/sup 95/ and Ce/sup 144/ were similar to levels found elsewhere (2 to 9, 1 to 3, 2 to 9, and 10 to 20 mu mu c/g respectively) and were presumably controlled by weapons fallout. Higher levels were found in small areas and indicate the need for attention to localized contamination, even though indirect estilevels considered hazardous from the standpoint of health physics. (auth)

Date: September 20, 1961

Creator: Olson, J.S.

Object Type: Report

System: The UNT Digital Library

(open access)

The Effect of Chemical Additives on the Synthesis of Ethanol

The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additives on the synthesis reaction may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from snygas. 27 refs., 2 figs., 2 tabs.

Date: September 20, 1991

Creator: Chuang, S. C. & Balakos, M. W.

Object Type: Report

System: The UNT Digital Library

(open access)

Current California legislative and regulatory activity impacting geothermal hydrothermal commercialization: monitoring report No. 2. Report No. 1020

The progress of four bills relating to geothermal energy is reported. The current regulatory activities of the California Energy Commission, the Lake County Planning Commission/Lake County Air Pollution Control District, the Governor's Office of Planning and Research, the State Lands' Commission, and the California Public Utilities Commission are reviewed. (MHR)

Date: April 20, 1980

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Anomalous isotopic composition of cosmic rays

Recent measurements of nonsolar isotopic patterns for the elements neon and (perhaps) magnesium in cosmic rays are interpreted within current models of stellar nucleosynthesis. One possible explanation is that the stars currently responsible for cosmic-ray synthesis in the Galaxy are typically super-metal-rich by a factor of two to three. Other possibilities include the selective acceleration of certain zones or masses of supernovas or the enhancement of /sup 22/Ne in the interstellar medium by mass loss from red giant stars and planetary nebulas. Measurements of critical isotopic ratios are suggested to aid in distinguishing among the various possibilities. Some of these explanations place significant constraints on the fraction of cosmic ray nuclei that must be fresh supernova debris and the masses of the supernovas involved. 1 figure, 3 tables.

Date: June 20, 1980

Creator: Woosley, S. E. & Weaver, T. A.

Object Type: Article

System: The UNT Digital Library

(open access)

Computor program for mathematical evaluation of the Rocky Flats nuclear accident dosimetry system

A computer program has been developed to facilitate the evaluation of the Rocky Flats Emergency Dosimetry System. This program evaluates data to determine the neutron fluence associated with a criticality accident. It is necessary to obtain information about the critical system for personnel dose estimates. Information pertaining to the geometry and position of the critical material and orientation of personnel, with respect to the material, is essential to supplement the calculations contained in this program.

Date: December 20, 1977

Creator: Wood, C. B.

Object Type: Report

System: The UNT Digital Library