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The impact of episodic nonequilibrium fracture-matrix flow on repository performance at the potential Yucca Mountain site

Description: Adequate representation of fracture-matrix interaction during episodic infiltration events is crucial in making valid hydrological predictions of repository performance at Yucca Mountain. Approximations have been applied to represent fracture-matrix flow interaction, including the Equivalent Continuum Model, which assumes capillary equilibrium between fractures and matrix, and the Fracture-Matrix Model, which accounts for nonequilibrium fracture-matrix flow and transport for the eight major hydrostratigraphic units in the unsaturated zone at Yucca Mountain. 18 refs., 6 figs., 3 tabs.
Date: November 1, 1991
Creator: Buscheck, T.A.; Nitao, J.J. & Chesnut, D.A.
Partner: UNT Libraries Government Documents Department

Progress in assessing the effect of ionizing radiation on the anticipated waste package environment at the Yucca Mountain potential repository site

Description: Progress in establishing the effect of ionizing radiation on the expected air/water vapor waste package environment is summarized. This work was performed at Argonne National Laboratory (ANL) in support of the Yucca Mountain Site Characterization Project. The radiolytic issues that have been identified are presented. Long-term gamma experiments with gas compositions ranging from dry air to high-humidity air were completed. The predominant nitrogen fixation products in all air-like systems studied were nitrogen dioxide and nitric acid. Yields between 0.8 and 2.3 molec/100 eV have been measured. Ammonia formation, although not predominant, was also observed at temperature below 100{degrees}C. The ammonia yields were low, and the concentration did not build up with increased absorbed dose. The status of the issues identified is given.
Date: December 31, 1991
Creator: Reed, D.T.
Partner: UNT Libraries Government Documents Department

Nuclear magnetic resonance determination of the non-pore water content of zeolitic tuffs and its application to correction of epithermal-neutron-log-derived water content

Description: The use of free water obtained from correction of log-derived total water for the non-pore water measured on desiccated samples appears to result in more plausible values for calculated saturation properties in zeolitized rocks. There is evidence that grain density can best be measured using helium pyncnometry of samples kept at a controlled humidity. The best procedure would be to measure both grain density and bound water in the same samples at the same humidity. Under those conditions, desiccation would not be necessary, and the values of grain density and water content used in Eq. (1) would be completely compatible. This procedure should improve our site characterizations. 7 refs., 4 figs., 1 tab.
Date: September 1, 1991
Creator: McKague, H.L.; Hearst, J.R. & Ward, R.L.
Partner: UNT Libraries Government Documents Department

Geochemical evidence for waning magmatism and polycyclic volcanism at Crater Flat, Nevada

Description: Petrologic and geochemical studies of basaltic rocks in the Yucca Mountain region are currently focused on understanding the evolution of volcanism in the Crater Flat volcanic field and the mechanisms of polycyclic volcanism at the Lathrop Wells volcanic center, the youngest center in the Crater Flat volcanic field. Geochemical and petrologic data indicate that the magma chambers which supplied the volcanic centers in Crater Flat became situated at greater crustal depths as the field evolved. Deep magma chambers may be related to a waning magma flux that was unable to sustain upper crystal magma conduits and chambers. Geochemical data from the Lathrop Wells volcanic center indicate that eruptive units identified from field and geomorphic relationships are geochemically distinct. The geochemical variations cannot be explained by fractional crystallization of a single magma batch, indicating that several magma batches were involved in the formation of the Lathrop Wells center. Considering the low magma flux in the Yucca Mountain region in the Quaternary, the probability of several magma batches erupting essentially simultaneously at Lathrop Wells in considered remote. It is more likely that the Lathrop Wells center was formed by a series of eruptions that took place over many thousands of years. The geochemical data from Lathrop Wells is consistent with the concept of a complex, polycyclic volcano, which was originally proposed based on geomorphic and soil-development data.
Date: December 31, 1991
Creator: Perry, F.V. & Crowe, B.M.
Partner: UNT Libraries Government Documents Department

LLW Forum meeting report, April 18--19, 1991

Description: The Low-Level Radioactive Waste Forum is an association of representatives of states and compacts established to facilitate state and compact commission implementation of the Low-Level Radioactive Waste Policy Act of 1980 and the Low-Level Radioactive Waste Policy Amendments Act of 1985 and to promote the objectives of low-level radioactive waste regional compacts. The Forum provides an opportunity for states and compacts to share information with one another and to exchange views with officials of federal agencies. LLW Forum participants include representatives from regional compacts, designated host states, unaffiliated states, and states with currently- operating low-level radioactive waste facilities. This quarterly meeting was held on April 18-19, 1991.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Evaluation of wave dispersion, mode-conversion, and damping for ECRH with exact relativistic corrections

Description: The complex dispersion functions of Eq. (3) in Ref. 1 have recently been computed accurately and reliably over their entire range of parameters, without recourse to the usual slightly-relativistic approximation, which may have difficulty for oblique incidence. In the future, the local dispersion properties of ECRF waves will be reevaluated for parameters of interest to ECRF conditions in several existing and proposed fusion experiments, with particular emphasis on the damping and mode-conversion of both ordinary and extraordinary waves to electrostatic waves near the upper hybrid and cyclotron frequencies.
Date: December 31, 1991
Creator: Smithe, D.N. & Colestock, P.L.
Partner: UNT Libraries Government Documents Department

Annual meeting of the Calorimetry Exchange Program: minutes--April 24-25, 1991

Description: On April 24-25, 1991, people from seven DOE organizations participated in the annual meeting of the Calorimetry Exchange Program. The meeting featured a review of the statistical analysis of the calorimetry and gamma-ray data submitted to the exchange program during 1990. The meeting also enabled the group to review progress of five projects concerning a tritium exchange program, reprogramming of the database, a catalogue of measurement techniques, additional samples, and recharacterization of the current sample. There were presentations on recent advances in calorimetry and gamma-ray measurements.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Small Inertial Fusion Energy (IFE) demonstration reactors

Description: ICF target design studies done for the Nova Upgrade have identified conditions under which the target ignition ``cliff`` is shifted to much lower drive energy albeit with the penalty that the gain achieved at a given energy is also smaller. These targets would repeatedly produce the output and spectra of a higher gain targets at low yield. They should, thus, allow building much smaller R&D reactors with full thermonuclear effects. Demonstration reactor at the 1 to 100 MW{sub e} level appear to be feasible with driver energies of 0.5 to 2.0 MJ per pulse. These smaller, less expensive test and demonstration facilities should result in lower IFE development cost. If the U.S. government builds a driver and target factory, it is also conceivable that commercial organizations could build their own scaled concepts of IFE reactors using the beams and targets supplied by the government`s facilities.
Date: October 3, 1991
Creator: Hogan, W.J.
Partner: UNT Libraries Government Documents Department

Multi-spectral automated rotating shadowband radiometry in the Atmospheric Radiation Measurement (ARM) Program

Description: This paper discusses the work in progress to develop two RSR variants that extend this measurement technique to make measurements at multiple wavelengths. One of these instruments uses independent interference-filter/photodiode detectors to measure any seven wavelength bands chosen between 350 nm and 2.5 {micro}m, and the other uses a prism spectrograph coupled to a Charge-Coupled Device (CCD) array to measure 256 wavelength intervals from 370 nm to 1 {micro}m. These instruments provide spectrally resolved measurements of the direct-normal, total horizontal, and diffuse horizontal irradiances. These parameters of the sky-radiance function are measured using the same detector (for a given wavelength), eliminating the difficulties inherent in comparing these data when they are taken by independent detectors. The data are measured synchronously, and can be measured at intervals as short as 10 seconds if desired, though more normally data are taken at 15 second intervals and averaged over 1 to 5 minutes. Field deployment of the multiple filter instruments has begun, and twelve of these instruments will be deployed this year as part of the United States Department of Energy (DOE) Quantitative Links measurement program. In addition, further development and testing of these instruments is underway as part of the Atmospheric Radiation Measurement Program also sponsored by DOE.
Date: December 31, 1991
Creator: Harrison, L.
Partner: UNT Libraries Government Documents Department

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 9: Evaluation of Additional Pentaphene, Pentacene, and Pyranthrene Compounds as Possible Solvent Polarity Probes

Description: Article on polycyclic aromatic hydrocarbon solute probes and an evaluation of additional pentaphene, pentacene, and pyranthrene compounds as possible solvent polarity probes.
Date: March 1, 1991
Creator: Tucker, Sheryl A. (Sheryl Ann); Zvaigzne, Anita I.; Acree, William E. (William Eugene); Fetzer, John Charles, 1953- & Zander, Maximilian
Partner: UNT College of Arts and Sciences

Field trip guide to selected outcrops, Arbuckle Mountains, Oklahoma

Description: The Arbuckle Mountains, named for Brigadier General Matthew Arbuckle, are located in south-central Oklahoma. The formations that comprise the Arbuckle Mountains have been extensively studied for hydrocarbon source rock and reservoir rock characteristics that can be applied to the subsurface in the adjacent Anadarko and Ardmore basins. Numerous reports and guidebooks have been written concerning the Arbuckle Mountains. A few important general publications are provided in the list of selected references. The purpose of this handout is to provide general information on the geology of the Arbuckle Mountains and specific information on the four field trip stops, adapted from the literature. The four stops were at: (1) Sooner Rock and Sand Quarry; (2) Woodford Shale; (3) Hunton Anticline and Hunton Quarry; and (4) Tar Sands of Sulfur Area. As part of this report, two papers are included for more detail: Paleomagnetic dating of basinal fluid migration, base-metal mineralization, and hydrocarbon maturation in the Arbuckle Mountains, Oklahoma and Laminated black shale-bedded chert cyclicity in the Woodford Formation, southern Oklahoma.
Date: November 17, 1991
Partner: UNT Libraries Government Documents Department

LLW Forum meeting report

Description: This document reports the details of the Quarterly Meeting of the Low- Level Radioactive Waste Forum held in San Diego, California during January 23-25, 1991. Topics discussed include: State and Compact Progress Reports; Legal Updates; Update on Technical Assistance; Advanced Notice of Proposed Rulemaking Regarding Surcharge Rebates; Update on TCC Activities; NRC Update; Disposal of Commercial Mixed Waste; Update on EPA Activities; ACNW Working Group on Mixed Waste; National Profile on Mixed Waste; Commercial Perspective on Mixed Waste; Update on DOT Activities; Source Terms; Materials and Waste; Storage: and Waste Acceptance Criteria and Packaging.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Measurements of the {sup 235}U(n,f) cross section in the 3 to 30 MeV neutron energy region

Description: To improve the accuracy of the {sup 235}U(n,f) cross section, measurements have been made of this standard cross section at the target 4 facility at Los Alamos National Laboratory (LANL). The data were obtained at the 20-meter flight path of that facility. The fission reaction rate was determined with a fast parallel plate ionization chamber and the neutron fluence was measured with an annular proton recoil telescope. The measurements provide the shape of the {sup 235}U(n,f) cross section relative to the hydrogen scattering cross section for neutron energies from about 3 to 30 MeV neutron energy. The data have been normalized to the very accurately known value near 14 MeV. The results are in good agreement with the ENDF/B-VI evaluation up to about 15 MeV neutron energy. Above this energy differences as large as 5% are observed.
Date: December 31, 1991
Creator: Carlson, A.D.; Wasson, O.A. & Lisowski, P.W.
Partner: UNT Libraries Government Documents Department

Sedimentary basin geochemistry and fluid/rock interactions workshop

Description: Fundamental research related to organic geochemistry, fluid-rock interactions, and the processes by which fluids migrate through basins has long been a part of the U.S. Department of Energy Geosciences program. Objectives of this program were to emphasize those principles and processes which would be applicable to a wide range of problems associated with petroleum discovery, occurrence and extraction, waste disposal of all kinds, and environmental management. To gain a better understanding of the progress being made in understanding basinal fluids, their geochemistry and movement, and related research, and to enhance communication and interaction between principal investigators and DOE and other Federal program managers interested in this topic, this workshop was organized by the School of Geology and Geophysics and held in Norman, Oklahoma in November, 1991.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Stationary second-degree iterative methods and recurrences

Description: The basic theory of stationary second-degree iterative methods is presented from the point of view of recurrences. Recurrences are encountered in the development of expressions for the spectral radii and for various norms associated with linear stationary iterative methods. We show that many of these recurrences are special cases of a single general recurrence and that its closed-form solution leads to these expressions. Citations are given showing where the expressions occur in the theory of iterative methods.
Date: February 1, 1991
Creator: Kincaid, D.R. & Young, D.M.
Partner: UNT Libraries Government Documents Department

Performance characteristics of an induction linac magnetic pulse compression modulator at multi-kilohertz pulse repetition frequencies

Description: The ETA-II linear induction accelerator utilizes four pulse power conditioning chains. Magnetic pulse compression modulators (MAG1-Ds) form the last stage of each chain. A single power conditioning chain is used to drive the injector; the remaining three are used to drive 60 accelerator cells. Nominal parameters of the MAG1-D are an output voltage of greater than 120 kV, pulse width of 70 ns, and an output impedance of 2 ohms. Our operations goal for ETA-II is stable high average power operation at 5 kHz PRF. We have begun upgrading and characterizing the power conditioning chain on our High Average Power Test Stand (HAPTS). On HAPTS, the pulse to pulse amplitude stability has been improved to less than 0.7% (one sigma) and of order 3-5 ns random jitter about a systematic timing variation. In this paper we describe the status of our work to achieve the this paper we describe the status of our work to achieve the average power operation of ETA-II
Date: May 1, 1991
Creator: Sampayan, S.E.; Chambers, F.W. & Deadrick, F.J.
Partner: UNT Libraries Government Documents Department