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An analytical and experimental study was performed on the use of lanthanide oxides (La-oxides) as surrogates for plutonium oxides (PuO{sub 2}) during simulated buried waste retrieval. This study determined how well the La-oxides move compared to PuO{sub 2} in aerosolized soils during retrieval scenarios. As part of the analytical study, physical properties of La-oxides and PuO{sub 2}, such as molecular diameter, diffusivity, density, and molecular weight are compared. In addition, an experimental study was performed in which Idaho National Engineering Laboratory (INEL) soil, INEL soil with lanthanides, and INEL soil with plutonium were aerosolized and collected in filters. Comparison of particle size distribution parameters from this experimental study show similarity between INEL soil, INEL soil with lanthanides, and INEL soil with plutonium.

In a long-term program that began in 1984, limestone and marble briquettes have been exposed to both anthropogenic acid deposition and natural weathering at four field sites in the eastern United States.

We present the design and implementation of a very compact adaptive optic system that senses the return light from a sodium guide-star and controls a deformable mirror and a pointing mirror to compensate atmospheric perturbations in the wavefront. The deformable mirror has 19 electrostrictive actuators and triangular subapertures. The wavefront sensor is a Hartmann sensor with lenslets on triangular centers. The high-bandwidth steering mirror assembly incorporates an analog controller that samples the tilt with an avalanche photodiode quad cell. An {line_integral}/25 imaging leg focuses the light into a science camera that can either obtain long-exposure images or speckle data. In laboratory tests overall Strehl ratios were improved by a factor of 3 when a mylar sheet was used as an aberrator. The crossover frequency at unity gain is 30 Hz.

In a long-term program that began in 1984, limestone and marble briquettes have been exposed to both anthropogenic acid deposition and natural weathering at four field sites in the eastern United States. Similar tests began at an Ohio site in 1986. Effects of exposure on the briquettes and other materials at the sites are evaluated periodically by several federal agencies cooperating in the National Acid Precipitation Assessment Program (NAPAP). One of the primary contributions of Argonne National Laboratory to the NAPAP has been the measurement of tristimulus color change on samples exposed to the environment. Results from the first six years indicate a yellowing of the marble and a darkening of limestone on both the skyward and groundward surfaces of fresh and preexposed briquettes. The relationship between discoloration and exposure period appears to be linear. Discoloration rates as a function of a cumulative exposure time are almost constant for marble and slightly decreasing for limestone Dark spots on groundward surfaces were measured with tristimulus color equipment prior to chemical analysis to determine if a correlation exists between darkening (change in reflectance) and SO{sub 4} concentration. Taking exposure time into consideration, and assuming that the airborne concentration of dark particles, which …

Thermal discharge requirements for power plants using once-through cooling systems are based on state water quality standards for temperatures that must be met outside of designated mixing zones. This study evaluates the impact of limiting the extent of thermal mixing zones. This study evaluates the impact of limiting the extent of thermal mixing zones to no more than 1,000 feet from the discharge point. Data were collected from 79 steam electric plants. Of the plants currently using once-through cooling systems, 74% could not meet current thermal standards at the edge of a 1,000-foot mixing zone. Of this total, 68% would retrofit cooling towers, and 6% would retrofit diffusers. The estimated nationwide capital cost for retrofitting plants that could not meet current thermal standards at the edge of a 1,000-foot mixing zone is $21.4 billion. Conversion of a plant from once-through cooling to cooling towers or addition of diffusers would result in a lower energy output from that plant. For the affected plants, the total estimated replacement cost would be $370 to $590 million per year. Some power companies would have to construct new generating capacity to meet the increased energy demand. The estimated nationwide cost of this additional capacity would …

The Environmental Science Group of Los Alamos National Laboratory collected soil water content data using Time Domain Reflectometry (TDR) and neutron probe in order to correlate the results from the two techniques in a study performed at Los Alamos, NM. Two well-characterized field plots (3m {times} 10m) were instrumented with TDR waveguides and neutron probe access tubes at four locations. At each location, TDR rod pairs were placed horizontally at 5-,15-,30-,45- and 60-cm depths and vertical sets of rod pairs with lengths of 15-,30-,45- and 60-cm were installed. Neutron probe measurements were taken at 15-,30-,45- and 60-cm depths. Because the neutron probe measures a spherical volume, soil water content values were compared with horizontal TDR readings averaged over the same zone. Additionally, vertical TDR readings were compared to neutron probe readings averaged over the depths corresponding to each TDR length. Measurements for each technique were taken weekly since Fall of 1992. A time series comparison of the results is presented.

Chloroprene, 2-chloro-1,3-butadiene, is a colorless liquid with a pungent ethereal odor that is primarily used as an intermediate in the manufacture of neoprene rubber, and has been used as such since about 1930. This study addressed the potential for chloroprene to cause developmental toxicity in New Zealand white rabbits following gestational exposure to 0, 10, 40, or 175 ppm chloroprene vapors, 6h/dy, 7dy/wk. Each treatment group consisted of 15 artificially inseminated females exposed on 6 through 28 days of gestation (dg). Body weights were obtained throughout the study period, and uterine and fetal body weights were obtained at sacrifice on 29 dg. Implants were enumerated and their status recorded and live fetuses were examined for gross, visceral, skeletal, and soft-tissue craniofacial defects. There were no overt signs of maternal toxicity and the change in maternal body weight over the course of the study was not affected. Exposure of pregnant rabbits to chloroprene vapors on 6-28 dg had no effect on the number of implantation, the mean percent of live pups per litter, or on the incidence of resorptions per litter. The incidence of fetal malformations was not increased by exposure to chloroprene. Results of this study indicate that gestational exposure …

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

The objective of this research project has been to investigate the potential for using temperature-dependent (thermal) precipitation of chemicals to reduce the porosity and permeability of porous rocks. The method consists of injecting hot water that is saturated in a chemical that will precipitate upon cooling. Through this process, the permeability of thief zones in oil reservoirs could be reduced, allowing improved recovery by secondary and tertiary recovery processes. The chemical literature was reviewed for environmentally safe chemicals that have a suitable temperature-dependent solubility for the thermal precipitation process. Four suitable chemicals were identified: boron oxide, potassium carbonate, sodium borate, and potassium chloride. An experimental apparatus was constructed to test the thermal precipitation process at high temperatures and pressures. Data was collected with clastic Berea sandstone cores using two chemicals: potassium carbonate and sodium borate. Data was also collected with limestone cores using potassium carbonate. The porosities and permeabilities were measured before and after being treated by the thermal precipitation process. A theoretical study of the process was also conducted. A model for predicting the fractional reduction in porosity was developed that is based on the temperature-dependent solubility of the chemical used. An empirical model that predicts the fractional reduction …

Most enhanced oil recovery schemes involve the displacement of a more dense and more viscous oil by a less dense and less viscous fluid in a heterogeneous porous medium. The interaction of heterogeneity with the several competing forces, namely, viscous, capillary, gravitational, and dispersive forces, can conspire to make the displacements unstable and difficult to model and to predict. The objective of this research was to develop a systematic methodology for modeling unstable fluid displacements in heterogeneous media. Flow visualization experiments were conducted using X-ray computed tomography imaging and a video imaging workstation to gain insights into the dynamics of unstable displacements, acquire detailed quantitative experimental image data for calibrating numerical models of unstable displacements, and image and characterize heterogeneities in laboratory cores geostatistically. High-resolution numerical models modified for use on vector-architecture supercomputers were used to replicate the image data. Geostatistical models of reservoir heterogeneity were incorporated in order to study the interaction of hydrodynamic instability and heterogeneity in reservoir displacements. Finally, a systematic methodology for matching the experimental data with the numerical models and scaling the laboratory results to other systems were developed. The result is a new method for predicting the performance of unstable EOR displacements in the …

This report contains: (1) FY 1993 AGS schedule as run; (2) FY 1994--95 AGS schedule; (3) AGS experiments {ge} FY 1993 (as of 30 March 1994); (4) AGS beams 1993; (5) AGS experimental area FY 1991 physics program; (6) AGS experimental area FY 1992 physics program; (7) AGS experimental area FY 1993 physics program; (8) AGS experimental area FY 1994 physics program (planned); (9) a listing of experiments by number; (10) two-page summaries of each experiment; (11) listing of publications of AGS experiments; and (12) listing of AGS experiments.

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Monthly newspaper from Oklahoma City, Oklahoma that includes news and information about the Churches of Christ along with advertising.

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state, and national news along with extensive advertising.

Experiments were conducted to assess the effects of high potential testing of cables and to assess the survivability of aged and damaged cables under Loss-of-Coolant Accident (LOCA) conditions. High potential testing at 240 Vdc/mil on undamaged cables suggested that no damage was incurred on the selected virgin cables. During aging and LOCA testing, Okonite ethylene propylene rubber (EPR) cables with a bonded jacket experienced unexpected failures. The failures appear to be primarily related to the level of thermal aging and the presence of a bonded jacket that ages more rapidly than the insulation. For Brand Rex crosslinked polyolefin (XLPO) cables, the results suggest that 7 mils of insulation remaining should give the cables a high probability of surviving accident exposure following aging. The voltage necessary to detect when 7 mils of insulation remain on unaged Brand Rex cables is approximately 35 kVdc. This voltage level would almost certainly be unacceptable to a utility for use as a damage assessment tool. However, additional tests indicated that a 35 kvdc voltage application would not damage virgin Brand Rex cables when tested in water. Although two damaged Rockbestos silicone rubber cables also failed during the accident test, no correlation between failures and level …