Report of Foreign Travel of Environmental Sciences Research Staff, October 1990 (open access)

Report of Foreign Travel of Environmental Sciences Research Staff, October 1990

BIOMOVS (BIOspheric MOdel Validation Study) is an international cooperative study initiated in 1985 by the Swedish National Institute of Radiation Protection to test models designed to calculate the environmental transfer and bioaccumulation of radionuclides and other trace substances. The objective of the symposium and workshop was to synthesize results obtained during Phase 1 of BIOMOVS (the first five years of the study) and to suggest new directions that might be pursued during Phase 2 of BIOMOVS. The travelers were an instrumental part of the development of BIOMOVS. This symposium allowed the travelers to present a review of past efforts at model validation and a synthesis of current activities and to refine ideas concerning future development of models and data for assessing the fate, effect, and human risks of environmental contaminants. R. H. Gardner also visited the Free University, Amsterdam, and the National Institute of Public Health and Environmental Protection (RIVM) in Bilthoven to confer with scientists about current research in theoretical ecology and the use of models for estimating the transport and effect of environmental contaminants and to learn about the European efforts to map critical loads of acid deposition.
Date: November 7, 1990
Creator: Blaylock, B. Gordon; Hoffman, F. Owen & Gardner, Robert H.
Object Type: Report
System: The UNT Digital Library
Processing method for superconducting ceramics (open access)

Processing method for superconducting ceramics

A process for preparing a superconducting ceramic and particularly YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}, where {delta} is in the order of about 0.1--0.4, is carried out using a polymeric binder which decomposes below its ignition point to reduce carbon residue between the grains of the sintered ceramic and a nonhydroxylic organic solvent to limit the problems with water or certain alcohols on the ceramic composition.
Date: May 7, 1990
Creator: Bloom, I. D.; Poeppel, R. B. & Flandermeyer, B. K.
Object Type: Patent
System: The UNT Digital Library
Cumulative beam breakup of the ground-based-free-electron laser (open access)

Cumulative beam breakup of the ground-based-free-electron laser

Strategies employed by the Ground-Based Free Electron Laser system to maintain beam stability in its rf linac against cumulative beam breakup will be described. These strategies include a proper choice of cavity shape and the use of staggered tuning. Simulations show that the growths of effective transverse emittance due to cumulative beam breakup can be limited to 10%. 4 refs., 5 figs., 1 tab.
Date: August 7, 1990
Creator: Chan, K. C. D. & Spalek, G.
Object Type: Article
System: The UNT Digital Library
Effects of relativity of RTEX in collisions of U sup q+ with light targets (open access)

Effects of relativity of RTEX in collisions of U sup q+ with light targets

We have calculated the resonant transfer and excitation cross sections in collisions of U{sup q+} (q = 82, 89, 90) ion with H{sub 2}, He and C in impulse approximation using the multi-configuration Dirac-Fock method. The calculations were carried out in intermediate coupling with configuration interaction. The quantum electrodynamic and finite nuclear size corrections were included in the calculations of transition energies. The Auger rates were calculated including the contributions from Coulomb as well as the transverse Breit interactions. For U{sup 89+} and U{sup 90+}, effects of relatively not only shift the peak positions but also change the peak structure. The total dielectronic recombination strength has been found to increase by 50% due to the effects of relativity. The present theoretical RTEX cross sections for U{sup 90+} in hydrogen agree well with experiment. For U{sup 82+}, Breit interaction had been found to have little effect on the RTEX cross sections involving L-shell excitation. However, the spin-orbit interaction can still make significant change in the peak structure. 24 refs., 4 figs.
Date: November 7, 1990
Creator: Chen, Mau Hsiung.
Object Type: Article
System: The UNT Digital Library
Measurement and Simulation of Whole Beam Brightness on the ETA-II (Experimental Test Accelerator-II) Linear Induction Accelerator (open access)

Measurement and Simulation of Whole Beam Brightness on the ETA-II (Experimental Test Accelerator-II) Linear Induction Accelerator

Measurement of beam radius as a function of focusing strength of an upstream solenoidal field allows simultaneous determination of the beam energy, brightness and tilt of the phase space ellipse. On ETA-II beam radius has been measured by analyzing foil emitted Cherenkov light with a gated (5 ns) image intensified CCD camera. The beam energy measurement is corroborated with a spectrometer magnet and core brightness with a two hole emittance diagnostic. For a 6 MeV, 1.6 kA beam, the whole beam brightness was measured to be 4.0 {times} 10{sup 8} A/(m-rad){sup 2} with an inner core (few percent) brightness of 1.2 {times} 10{sup 9} A/(m-rad){sup 2}. The data was simulated with a particle transport code that includes the effects of energy sweep and magnetic misalignment. The code predicts a halo produced by an orbital resonance that is also observed experimentally.
Date: August 7, 1990
Creator: Chen, Y. J.; CLark, J. C.; Paul, A. C.; Nexsen, W. E. & Turner, W. C.
Object Type: Article
System: The UNT Digital Library
Experience with Position Sensitive Neutron Detectors at the Intense Pulsed Neutron Source (open access)

Experience with Position Sensitive Neutron Detectors at the Intense Pulsed Neutron Source

At the Intense Pulsed Neutron Source (IPNS) pulses of protons accelerated in a synchrotron produce pulses of fast neutrons via the spallation process in an enriched uranium target. After moderation, the resulting pulses of slow neutrons are directed into beams which serve a variety of neutron scattering instruments. Currently there are thirteen neutron scattering instruments in operation or under development at IPNS, and six of these use position-sensitive neutron detectors (PSDs). These PSDs are: a 30 cm {times} 30 cm, {approximately}3 mm resolution, neutron Anger camera area PSD with {sup 6}Li-glass scintillator; a 2.5 cm dia, {approximately}0.7 mm resolution, microchannel-plate area PSD with {sup 6}Li-glass scintillator; a 20 cm {times} 20 cm, {approximately}5 mm resolution, {sup 3}He proportional counter area PSD; a 40 cm {times} 40 cm, {approximately}4 mm resolution, {sup 3}He proportional counter area PSD; a flat 20 cm long, {approximately}1.6 mm resolution, {sup 3}He proportional counter linear PSD; and 160 cylindrical {sup 3}He proportional counter linear PSDs, each of which is 1.27 cm in dia 60 cm long and has {approximately}14 mm resolution. These detectors, in addition to being position-sensitive, resolve the time of the neutron capture with {approximately}1 {mu}s precision for neutron time-of-flight measurements. This paper will …
Date: May 7, 1990
Creator: Crawford, R. K.; Haumann, J. R.; Schultz, A. J.; Felcher, G. P.; Epperson, J. E.; Thiyagarajan, P. et al.
Object Type: Article
System: The UNT Digital Library
Bioechnology of indirect liquefaction (open access)

Bioechnology of indirect liquefaction

The project on biotechnology of indirect liquefaction was focused on conversion of coal derived synthesis gas to liquid fuels using a two-stage, acidogenic and solventogenic, anaerobic bioconversion process. The acidogenic fermentation used a novel and versatile organism, Butyribacterium methylotrophicum, which was fully capable of using CO as the sole carbon and energy source for organic acid production. In extended batch CO fermentations the organism was induced to produce butyrate at the expense of acetate at low pH values. Long-term, steady-state operation was achieved during continuous CO fermentations with this organism, and at low pH values (a pH of 6.0 or less) minor amounts of butanol and ethanol were produced. During continuous, steady-state fermentations of CO with cell recycle, concentrations of mixed acids and alcohols were achieved (approximately 12 g/l and 2 g/l, respectively) which are high enough for efficient conversion in stage two of the indirect liquefaction process. The metabolic pathway to produce 4-carbon alcohols from CO was a novel discovery and is believed to be unique to our CO strain of B. methylotrophicum. In the solventogenic phase, the parent strain ATCC 4259 of Clostridium acetobutylicum was mutagenized using nitrosoguanidine and ethyl methane sulfonate. The E-604 mutant strain of Clostridium …
Date: May 7, 1990
Creator: Datta, R.; Jain, M. K.; Worden, R. M.; Grethlein, A. J.; Soni, B.; Zeikus, J. G. et al.
Object Type: Report
System: The UNT Digital Library
Bioechnology of indirect liquefaction. Final report (open access)

Bioechnology of indirect liquefaction. Final report

The project on biotechnology of indirect liquefaction was focused on conversion of coal derived synthesis gas to liquid fuels using a two-stage, acidogenic and solventogenic, anaerobic bioconversion process. The acidogenic fermentation used a novel and versatile organism, Butyribacterium methylotrophicum, which was fully capable of using CO as the sole carbon and energy source for organic acid production. In extended batch CO fermentations the organism was induced to produce butyrate at the expense of acetate at low pH values. Long-term, steady-state operation was achieved during continuous CO fermentations with this organism, and at low pH values (a pH of 6.0 or less) minor amounts of butanol and ethanol were produced. During continuous, steady-state fermentations of CO with cell recycle, concentrations of mixed acids and alcohols were achieved (approximately 12 g/l and 2 g/l, respectively) which are high enough for efficient conversion in stage two of the indirect liquefaction process. The metabolic pathway to produce 4-carbon alcohols from CO was a novel discovery and is believed to be unique to our CO strain of B. methylotrophicum. In the solventogenic phase, the parent strain ATCC 4259 of Clostridium acetobutylicum was mutagenized using nitrosoguanidine and ethyl methane sulfonate. The E-604 mutant strain of Clostridium …
Date: May 7, 1990
Creator: Datta, R.; Jain, M. K.; Worden, R. M.; Grethlein, A. J.; Soni, B.; Zeikus, J. G. et al.
Object Type: Report
System: The UNT Digital Library
Arbitrary function generator for APS injector synchrotron correction magnets (open access)

Arbitrary function generator for APS injector synchrotron correction magnets

The APS injector synchrotron ring measures about 368 m in circumference. In order to obtain the precision of the magnetic field required for the positron acceleration from 450 Mev to 7.7 Gev with low beam loss, eighty correction magnets are distributed around its circumference. These magnets provide the vernier field changes required for beam orbit correction during the acceleration phase of the injector synchrotron cycle. Because of mechanical imperfections in the construction, as well as installation of real dipole and multi-pole magnets, the exact field correction required at each correction magnet location is not known until a beam is actually accelerated. It is therefore essential that a means is provided to generate a correction field that is a function of the beam energy from injection until extraction for each correction magnet. The fairly large number of correction magnets in the system requires that the arbitrary function generator design be as simple as possible yet provide the required performance. An important, required performance feature is that the function can be changed or modified ``on the fly``, to provide the operator with a real-time feel during the tune up process. The arbitrary function generator described in this report satisfies these requirements.
Date: November 7, 1990
Creator: Despe, O.D.
Object Type: Report
System: The UNT Digital Library
Strange meson and strangeonium spectroscopy: Introduction (open access)

Strange meson and strangeonium spectroscopy: Introduction

None
Date: December 7, 1990
Creator: Dunwoodie, W.
Object Type: Article
System: The UNT Digital Library
High power CW performance from a Ti:Sapphire laser and a single-pass amplifier (open access)

High power CW performance from a Ti:Sapphire laser and a single-pass amplifier

Using two argon-ion lasers to pump a CW Ti:Sapphire laser we have demonstrated consistent high power (19 watts) operation with a low order spatial mode. Thermal lensing effects were controlled by enclosing the laser in a vacuum and cooling the rod with liquid nitrogen. Using this laser we also demonstrated a CW Ti:Sapphire amplifier with an efficiency of 20%. 5 refs., 5 figs.
Date: November 7, 1990
Creator: Erbert, G. V.; Bass, I. L.; Hackel, R. P.; Jenkins, S.; Kanz, K. V. & Paisner, J. A.
Object Type: Article
System: The UNT Digital Library
Thermally Induced Structural Changes in Coal Combustion (open access)

Thermally Induced Structural Changes in Coal Combustion

The project objectives are (1) to measure the effect of devolatilization temperature and time on properties of the char and (2) characterize and quantify the effect of thermal annealing on char reactivity during char burnout under conditions of pulverized combustion. Coal devolatilization runs continued during the reporting period. Elemental analysis and N{sub 2} BET surface areas measurements were carried out on the three chars produced in the devolatilization runs. The results are presented. Experiments in the electrodynamic balance during the reporting period were focused on developing ways to measure the particle mass loss and, therefore, the reaction rate directly. This work is summarized in the attached Appendix. 4 refs., 1 fig., 1 tab.
Date: December 7, 1990
Creator: Gavalas, G. R. & Flagan, R. C.
Object Type: Report
System: The UNT Digital Library
16 Channel ECL repeater (open access)

16 Channel ECL repeater

This paper describes the circuits of a 16 channel CL repeater. (LSP)
Date: March 7, 1990
Creator: Graupman, Dan
Object Type: Report
System: The UNT Digital Library
Molecular cytogenetics using fluorescence in situ hybridization (open access)

Molecular cytogenetics using fluorescence in situ hybridization

Fluorescence in situ hybridization (FISH) with chromosome-specific probes enables several new areas of cytogenetic investigation by allowing visual determination of the presence and normality of specific genetic sequences in single metaphase or interphase cells. in this approach, termed molecular cytogenetics, the genetic loci to be analyzed are made microscopically visible in single cells using in situ hybridization with nucleic acid probes specific to these loci. To accomplish this, the DNA in the target cells is made single stranded by thermal denaturation and incubated with single-stranded, chemically modified probe under conditions where the probe will anneal only with DNA sequences to which it has high DNA sequence homology. The bound probe is then made visible by treatment with a fluorescent reagent such as fluorescein that binds to the chemical modification carried by the probe. The DNA to which the probe does not bind is made visible by staining with a dye such as propidium iodide that fluoresces at a wavelength different from that of the reagent used for probe visualization. We show in this report that probes are now available that make this technique useful for biological dosimetry, prenatal diagnosis and cancer biology. 31 refs., 3 figs.
Date: December 7, 1990
Creator: Gray, J.W.; Kuo, Wen-Lin; Lucas, J.; Pinkel, D.; Weier, H-U. & Yu, Loh-Chung.
Object Type: Article
System: The UNT Digital Library
Characterization of rocket propellant combustion products: Description of sampling and analysis methods for rocket exhaust characterization studies (open access)

Characterization of rocket propellant combustion products: Description of sampling and analysis methods for rocket exhaust characterization studies

A systematic approach has been developed and experimentally validated for the sampling and chemical characterization of the rocket motor exhaust generated from the firing of scaled down test motors at the US Army's Signature Characterization Facility (ASCF) at Redstone Arsenal in Huntsville, Alabama. The overall strategy was to sample and analyze major exhaust constituents in near real time, while performing off-site analyses of samples collected for the determination of trace constituents of the particulate and vapor phases. Initial interference studies were performed using atmospheric pressure burns of 1 g quantities of propellants in small chambers at Oak Ridge National Laboratory. Carbon monoxide and carbon dioxide were determined using non-dispersive infrared instrumentation. Hydrogen cyanide, hydrogen chloride, and ammonia determinations were made using ion selective electrode technology. Oxides of nitrogen were determined using chemiluminescence instrumentation. Airborne particulate mass concentration was determined using infrared forward scattering measurements and a tapered element oscillating microbalance, as well as conventional gravimetry. Particulate phase metals were determined by collection on Teflon membrane filters, followed by inductively coupled plasma and atomic absorption analysis. Particulate phase polynuclear aromatic hydrocarbons (PAH) and nitro-PAH were collected using high volume sampling on a two stage filter. Target species were extracted, and quantified …
Date: June 7, 1990
Creator: Jenkins, R.A.
Object Type: Report
System: The UNT Digital Library
Accident analysis and safety review of DOE Category B reactors (open access)

Accident analysis and safety review of DOE Category B reactors

DOE is employing the principle of comparability with the NRC requirements to guide its safety program. Since the safety record of research reactors licensed by the NRC has been established and accepted, the comparison of DOE Orders applicable to DOE research reactors with the NRC regulations applicable to research reactors would identify strengths and weaknesses of the DOE Orders. The comparison was made in 14 general topics of safety which are labeled Areas of Safety Concerns. This paper focuses on the Area of accident analysis and safety review and presents recommendations in these areas. 12 refs.
Date: August 7, 1990
Creator: Kimura, C. Y.
Object Type: Article
System: The UNT Digital Library
A technique for shell compression measurements of laser fusion targets by neutron activation of a rubidium tracer (open access)

A technique for shell compression measurements of laser fusion targets by neutron activation of a rubidium tracer

At the Nova Laser, the activation of a rubidium tracer incorporated in the shell of ICF targets has become a standard diagnostic technique for measuring the compressed shell areal density {l angle}{rho}{Delta}R{r angle}. The isotope {sup 85}Rb is activated by 14 MeV implosion neutrons to produce the isomer {sup 84m}Rb(t{sub {1/2}} = 20.5 min) which is used to determine the shell {l angle}{rho}{Delta}R{r angle} while the radioactive isotope {sup 86}Rb(t{sub 1/2} = 18.8 d) is used to determine the fraction of target debris collected as well as to assay the amount of rubidium in the target. The {sup 85}Rb(n,2n){sup 84m}Rb cross-section at 14.1 MeV was measured ({sigma} = 0.514 {plus minus} 0.080 b). Details of the detector system and experimental technique are given. 12 refs., 2 tabs.
Date: December 7, 1990
Creator: Lane, S.M. & Nelson, M.B.
Object Type: Article
System: The UNT Digital Library
Timing between streak cameras with a precision of 10 ps (open access)

Timing between streak cameras with a precision of 10 ps

The laser beams irradiating a target at the Nova laser facility comprise a set of ten simultaneous events. Two streak cameras, whose resolutions are 40 ps, record the power history for each beam, five beams to a camera; their time bases are cross-timed with a fiducial pulse. Analysis of data recorded for target experiments conducted over a six month period show the precision for cross-timing signals between two streak cameras to be {plus minus}9 ps and for characterizing a single temporal feature of a pulse to be {plus minus}5 ps. Beam synchronization at the end of six months was within 20 ps of the synchronization at the beginning of the experiments. A beam timing shift greater than 25 ps can be detected on a single laser shot; shifts of 10 to 20 ps require several shots to detect. 2 refs., 6 figs.
Date: December 7, 1990
Creator: Lerche, R. A.
Object Type: Article
System: The UNT Digital Library
A systematic study of actinide production from the interactions of heavy ions with sup 248 Cm (open access)

A systematic study of actinide production from the interactions of heavy ions with sup 248 Cm

Production cross sections for heavy actinides produced from the interactions of {sup 12}C, {sup 31}P, {sup 40}Ar, and {sup 44}Ca ions with {sup 248}Cm were measured at energies ranging from 0.98 to 1.35 X Coulomb barrier. The recoiling reaction products were collected in copper or gold catcher foils located near the {sup 248}Cm target. Separate fractions of Bk, Cf, Es, Fm, and Md were obtained from a radiochemical separation procedure. For the {sup 12}C system, a He/KCl jet was used to transport the recoiling No activities of interest to a rotating wheel system. The isotopic distributions of the actinide products were found to be essentially symmetric about the maximum with full-widths-at-half-maximum of approximately 2.5 mass units. Isotopic distributions of the {sup 12}C, {sup 31}P, {sup 40}Ar, and {sup 44}Ca systems were found to be very similar to the {sup 40,48}Ca systems studied previously. The maxima of the isotopic distributions generally occurred for those reaction channels which involved the exchange of the fewest number of nucleons between the target and projectile for which the calculated excitation energy was a positive quantity. Additionally, the maxima of the excitation functions occurred at those projectile energies which were consistent with the calculated reaction barriers …
Date: September 7, 1990
Creator: Leyba, J.D.
Object Type: Report
System: The UNT Digital Library
Feed-forward compensation for transient beam loading of the 805 MHz debuncher for the Fermilab linac upgrade (open access)

Feed-forward compensation for transient beam loading of the 805 MHz debuncher for the Fermilab linac upgrade

The expected momentum spread from the 400 MeV upgrade of the Fermilab linac is {plus minus}0.19% growing to about {plus minus}0.25% in 63 m of beam transport to the booster synchrotron. The desired injection value is about {plus minus}0.05%. An 805 MHz (h=1) debuncher is located 47 m downstream of the linac to reduce the momentum spread and the differences in mean energy between bunches. The beam pulse to the booster will vary from about 2--15 {mu}s at average current of 30--50 mA depending on program need. During 15 {mu}s the beam excitation of the debuncher can reach 2.2 MV/m for a three-cell cavity. This gradient is comparable to, but 90{degree} out of phase with, the 3.85 MV/m required to minimize the momentum spread. We choose to use feed-forward compensation to control the cavity field for the entire beam pulse. We discuss some general features of transient beam loading as well as the design and detailed simulation of the compensation scheme.
Date: September 7, 1990
Creator: MacLachlan, J. A.; Mills, F. E. & Owens, T.
Object Type: Article
System: The UNT Digital Library
Chloride anion exchange coprocessing for recovery of plutonium from pyrochemical residues and Cs sub 2 PuCl sub 6 filtrate (open access)

Chloride anion exchange coprocessing for recovery of plutonium from pyrochemical residues and Cs sub 2 PuCl sub 6 filtrate

Continuing studies of plutonium recovery from direct oxide reduction (DOR) and electrorefining (ER) pyrochemical process residues show that chloride anion exchange coprocessing is useful and effective. Coprocessing utilizes DOR residue salt as a reagent to supply the bulk of chloride ion needed for the chloride anion exchange process and to improve ER residue salt solubility. ER residue salt and ER scrapeout can be successfully treated, either alone or together, using coprocessing. In addition, chloride anion exchange at 2.0M acidity results in improved process performance by greatly reducing disproportionation of plutonium(IV), eliminating restrictions on oxidation time compared to operation at 1.0M acidity. Laboratory-scale experiments show that below-discard effluent plutonium losses are obtained. Resin capacity was 30 g Pu/{ell} or greater. Furthermore, it is feasible to perform chloride anion exchange recovery of plutonium from filtrate resulting from precipitation of dicesium hexachloroplutonate (Cs{sub 2}PuCl{sub 6}, an oxidant salt to be used in the molten salt extraction process) and integration of its preparation with recovery of DOR salts. 10 refs., 9 figs., 10 tabs.
Date: December 7, 1990
Creator: Muscatello, A. C. & Killion, M. E.
Object Type: Report
System: The UNT Digital Library
Bench-scale co-processing (open access)

Bench-scale co-processing

The objective of this current is to extend and optimize UOP's single-stage slurry-catalyzed co-processing scheme, which has developed under previous Contract AC22-84PC70002. Particular emphasis is given to defining and improving catalyst utilization and costs, evaluating alternative and disposable slurry-catalyst systems, and improving catalyst recycle and recovery techniques. The work during this quarter involved a series of bench-scale runs using a new Mo-based slurry catalyst. The results of bench-scale Runs 24 and 25 are discussed in the following report. 7 refs., 4 figs., 3 tabs.
Date: March 7, 1990
Creator: Nafis, D.A.; Gatsis, J.G.; Lea, C. & Miller, M.A.
Object Type: Report
System: The UNT Digital Library
Spectroscopic study of coal structure and reactivity (open access)

Spectroscopic study of coal structure and reactivity

Work done during this period (December 15, 1989 to March 14, 1990) covered two of the three primary areas of study of this project. The first involved the continuing development a of step-scanning interferometer for the photoacoustic depth-profiling of materials whose composition varies in the spatial region between 5 and 50 {mu}m from its surface. The second covered the initial construction of an on-line interface between a supercritical fluid chromatograph (SFC) and a Fourier transform infrared (FT-IR) spectrometer for monitoring the composition of coal extracts. 5 refs., 8 figs.
Date: September 7, 1990
Creator: Rabenstein, D.L.
Object Type: Report
System: The UNT Digital Library
Spectroscopic study of coal structure and reactivity (open access)

Spectroscopic study of coal structure and reactivity

The aim of this project is to perform quantitative analysis of the Fourier transform infrared (FT-IR) spectra of coals and coal extracts. The major difficulty encountered in the analysis of the FT-IR spectra of coals is the complexity of the bands, which consist of many closely overlapped peaks. Two techniques that are commonly used for the quantitative analysis of complex FT-IR spectra are deconvolution and curve-fitting. Deconvolution is a mathematical technique that narrows the speaks in a spectrum, thereby improving the effective resolution. Curve-fitting optimizes a set of ban parameters, using a least squares criterion, to simulate the true spectrum. We have recently completed work on optimizing the combination of these two techniques with the aim of applying this to the spectra of coals and coal extracts. Two types of deconvolution were investigated in this context: Fourier self-deconvolution (FSD) and maximum likelihood restoration (MLR). It was concluded that for noisy spectra MLR gave superior results. 3 refs., 7 figs.
Date: September 7, 1990
Creator: Rabenstein, D.L.
Object Type: Report
System: The UNT Digital Library