The Hexagon, Volume 92, Number 4, Winter 2001

The Hexagon, Volume 92, Number 4, Winter 2001

Date: Winter 2001
Creator: Alpha Chi Sigma
Description: Quarterly publication of the Alpha Chi Sigma chemistry fraternity containing articles related to chemistry research and the activities of the organization, including local chapters and groups.
Contributing Partner: UNT Libraries
Characterization of Contaminant Transport Using Naturally-Occurring U-Series Disequilibria

Characterization of Contaminant Transport Using Naturally-Occurring U-Series Disequilibria

Date: June 1, 2001
Creator: KU, TEH-LUNG
Description: Study the migration of nuclear waste contaminants in subsurface fractured systems using naturally occurring uranium and thorium-series radionuclides as tracers under in-situ physico-chemical and hydrogeologic conditions. Radioactive disequilibria among members of these decay-series nuclides can provide information on the rates of adsorption-desorption and transport of contaminants as well as on fluid transport and rock dissolution in a natural setting.
Contributing Partner: UNT Libraries Government Documents Department
Rediscovery of the Elements: Soddy and Isotopes

Rediscovery of the Elements: Soddy and Isotopes

Date: Winter 2010
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Description: Article describing Frederick Soddy's career and research of isotopes. Tourist information is included for areas significant to Soddy's life and work.
Contributing Partner: UNT College of Arts and Sciences
Rediscovery of the Elements: Thorium

Rediscovery of the Elements: Thorium

Date: Winter 2001
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
Description: Article recounting the discovery of the element Thorium in Norway by Hans Morten Thrane Esmark. Maps and tourist information regarding the area are provided.
Contributing Partner: UNT College of Arts and Sciences
Overview of research and development in subsurface fate and transport modeling

Overview of research and development in subsurface fate and transport modeling

Date: May 1, 1995
Creator: Sullivan, T.M. & Chehata, M.
Description: The US Department of Energy is responsible for the remediation of over 450 different subsurface-contaminated sites. Contaminant plumes at these sites range in volume from several to millions of cubic yards. The concentration of contaminants also ranges over several orders of magnitude. Contaminants include hazardous wastes such as heavy metals and organic chemicals, radioactive waste including tritium, uranium, and thorium, and mixed waste, which is a combination of hazardous and radioactive wastes. The physical form of the contaminants includes solutes, nonaqueous phase liquids (NAPLs), and vapor phase contaminants such as volatilized organic chemicals and radon. The subject of contaminant fate and transport modeling is multi-disciplinary, involving hydrology, geology, microbiology, chemistry, applied mathematics, computer science, and other areas of expertise. It is an issue of great significance in the United States and around the world. As such, many organizations have substantial programs in this area. In gathering data to prepare this report, a survey was performed of research and development work that is funded by US government agencies to improve the understanding and mechanistic modeling of processes that control contaminant movement through subsurface systems. Government agencies which fund programs that contain fate and transport modeling components include the Environmental Protection Agency, ...
Contributing Partner: UNT Libraries Government Documents Department
Hanford Site background: Evaluation of existing soil radionuclide data

Hanford Site background: Evaluation of existing soil radionuclide data

Date: July 1, 1995
Creator: unknown
Description: This report is an evaluation of the existing data on radiological background for soils in the vicinity of the Hanford Site. The primary purpose of this report is to assess the adequacy of the existing data to serve as a radiological background baseline for use in environmental restoration and remediation activities at the Hanford Site. The soil background data compiled and evaluated in this report were collected by the Pacific Northwest Laboratory (PNL) and Washington State Department of Health (DOH) radiation surveillance programs in southeastern Washington. These two programs provide the largest well-documented, quantitative data sets available to evaluate background conditions at the Hanford Site. The data quality objectives (DQOs) considered in this evaluation include the amount of data, number of sampling localities, spatial coverage, number and types of radionuclides reported, frequency of reporting, documentation and traceability of sampling and laboratory methods used, and comparability between sets of data. Although other data on soil radionuclide abundances around the Hanford Site exist, they are generally limited in scope and lack the DQOs necessary for consideration with the PNL and DOH data sets. Collectively, these two sources provide data on the activities of 25 radionuclides and four other parameters (gross alpha, gross ...
Contributing Partner: UNT Libraries Government Documents Department
Tentative method for the determination of plutonium-239 and plutonium-238 in water (by a coprecipitation anion exchange technique)

Tentative method for the determination of plutonium-239 and plutonium-238 in water (by a coprecipitation anion exchange technique)

Date: September 17, 1976
Creator: Bishop, C.T.; Brown, R.; Glosby, A.A.; Phillips, C.A. & Robinson, B.
Description: A procedure for the determination of plutonium 238 and plutonium 239 in water is described. The procedure consists of a coprecipitation, an anion exchange separation and electrodeposition, followed by alpha pulse height analysis. More specifically, the sample is acidified with nitric acid and plutonium-242 is added as a tracer before any chemical separations are performed. Iron is added to the water as iron (III) and the plutonium is coprecipitated with the iron as ferric hydroxide by adding ammonium hydroxide. After decantation and centrifugation, the ferric hydroxide precipitate containing the coprecipitated plutonium is dissolved and the solution is adjusted to 8M in HNO{sub 3} for anion exchange separation. When the sample fails to dissolve because of the presence of insoluble residue, the residue is treated by a rigorous acid dissolution using concentrated nitric acid and hydrofluoric acids. The sample is poured over an anion exchange column. The iron and most other elements that might be present pass through the column. Thorium is removed from the column with 12 M hydrochloric acid and then the plutonium is eluted by reducing it to plutonium (III) with the iodide ion. The plutonium is electrodeposited onto a stainless steel slide for counting by alpha pulse ...
Contributing Partner: UNT Libraries Government Documents Department
Savannah River Plant: 100 Area Reactors. Monthly report, May 1955

Savannah River Plant: 100 Area Reactors. Monthly report, May 1955

Date: June 15, 1955
Creator: unknown
Description: This report presents the details of the operation of the Savannah River Plant manufacturing division during the month of May 1955.
Contributing Partner: UNT Libraries Government Documents Department
Savannah River Plant heavy water: 400 Area. Monthly report, January 1955

Savannah River Plant heavy water: 400 Area. Monthly report, January 1955

Date: February 15, 1955
Creator: unknown
Description: This report presents the details of the operations of the Savannah River Plant manufacturing division during the month of January 1955.
Contributing Partner: UNT Libraries Government Documents Department
The University of Rochester Atomic Energy Project quarterly report, April 1, 1950--June 30, 1950

The University of Rochester Atomic Energy Project quarterly report, April 1, 1950--June 30, 1950

Date: December 31, 1950
Creator: Blair, H.A.
Description: This quarterly progress report gives an overview of the University of Rochester Atomic Energy Project for April 1, 1950 thru June 30, 1950. Sections included are entitled (1) Biological Effects of External Radiation (X-rays and gamma rays), (2) Biological Effects of External Radiation (Infra-red and ultraviolet), (3) Biological effects of radioactive materials (polonium, radon, thoron, and miscellaneous project materials), (4) Uranium, (5) Beryllium, (7) thorium, (8) fluoride, (9) zirconium, (10) special materials, (11) Isotopes, (12) Outside services, (12) Project health, (13) Health physics, (14) Special Clinical Service, and (15) Instrumentation (Spectroscopy, electron microscopy, x-ray and nuclear radiation detectors, x-ray diffraction, and electronics).
Contributing Partner: UNT Libraries Government Documents Department
Accelerator-driven transmutation of high-level waste from the defense and commercial sectors

Accelerator-driven transmutation of high-level waste from the defense and commercial sectors

Date: September 1996
Creator: Bowman, C.; Arthur, E. & Beard, C.
Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The major goal has been to develop accelerator transmutation of waste (ATW) system designs that will thoroughly and rapidly transmute nuclear waste, including plutonium from dismantled weapons and spent reactor fuel, while generating useful electrical power and without producing a long-lived radioactive waste stream. We have identified and quantified the unique qualities of subcritical nuclear systems and their capabilities in bringing about the complete destruction of plutonium. Although the 1191 subcritical systems involved in our most effective designs radically depart from traditional nuclear reactor concepts, they are based on extrapolations of existing technologies. Overall, care was taken to retain the highly desired features that nuclear technology has developed over the years within a conservative design envelope. We believe that the ATW systems designed in this project will enable almost complete destruction of nuclear waste (conversion to stable species) at a faster rate and without many of the safety concerns associated with the possible reactor approaches.
Contributing Partner: UNT Libraries Government Documents Department
Aquifer Transport of Th, U, Ra, and Rn In Solution and Colloids

Aquifer Transport of Th, U, Ra, and Rn In Solution and Colloids

Date: April 2, 2001
Creator: Wasserburg, G. J.
Description: The ability to safely store radioactive materials for long periods of time depends on our understanding of the conditions that mobilize the nuclei, which requires an understanding of the mechanisms of dissolution and transport in aquifers. The objective of this research was to gain an understanding of the dissolution and transport of naturally occurring uranium, thorium, and their radioactive daughter products in groundwater systems without using injected tracers or accidental contaminants. The study involved analyses of groundwater in and around the Brookhaven National Laboratory site and the water supply system. A theoretical model of continuous flow was developed considering chemical, physical, and geologic properties. This is the first model of water transport in the vadose zone and the groundwater table with water-rock interactions supplying insight into the problems of mobilization and precipitation. We derived clear theoretical predictions on U and Th behavior in groundwater. The combination of sound theory and good data was successful. Most of the variation in uranium isotopes was due to the original imprint of near-surface weathering and not to water-rock reactions at depth. It was shown that high radon content was not due to micropores in the minerals but a reflection of thorium precipitation on surfaces ...
Contributing Partner: UNT Libraries Government Documents Department
Portable sensor for hazardous waste. Final report, March 31, 1995--May 31, 1997

Portable sensor for hazardous waste. Final report, March 31, 1995--May 31, 1997

Date: December 31, 1997
Creator: Piper, L.G.; Hunter, A.J.R.; Fraser, M.E.; Davis, S.H. & Finson, M.L.
Description: This report summarizes accomplishments for the second phase of a 5-year program designed to develop a portable monitor for sensitive hazardous waste detection. The approach is to excite atomic fluorescence by the technique of Spark-Induced Breakdown Spectroscopy (SIBS). The principal goals for this second phase of the program were to demonstrate sensitive detection of additional species, both RCRA metals (Sb, Be, Cd, Cr, Pb, As, Hg) and radionuclides (U, Th, Tc); to identify potential applications and develop instrument component processes, including, sample collection and excitation, measurement and test procedures, and calibration procedures; and to design a prototype instrument. Successful completion of these task results in being able to fabricate and field test a prototype of the instrument during the program`s third phase.
Contributing Partner: UNT Libraries Government Documents Department
Measurement of Radon, Thoron, Isotopic Uranium and Thorium to Determine Occupational and Environmental Exposure and Risk at Fernald Feed Material Production Center

Measurement of Radon, Thoron, Isotopic Uranium and Thorium to Determine Occupational and Environmental Exposure and Risk at Fernald Feed Material Production Center

Date: July 1, 2004
Creator: Naomi H. Harley, Ph.D.
Description: To develop a new and novel area and personal radon/thoron detector for both radon isotopes to better measure the exposure to low airborne concentrations of these gases at Fernald. These measurements are to be used to determine atmospheric dispersion and exposure to radon and thoron prior to and during retrieval and removal of the 4000 Ci of radium in the two silos at Fernald.
Contributing Partner: UNT Libraries Government Documents Department
Uranium industry annual 1996

Uranium industry annual 1996

Date: April 1, 1997
Creator: unknown
Description: The Uranium Industry Annual 1996 (UIA 1996) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1996 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. Data on uranium raw materials activities for 1987 through 1996 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2006, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. A feature article, The Role of Thorium in Nuclear Energy, is included. 24 figs., 56 tabs.
Contributing Partner: UNT Libraries Government Documents Department
Biannual recalibration of two spectral gamma-ray logging systems used for baseline characterization measurements in the Hanford Tank Farms. Vadose Zone Characterization Project at the Hanford Tank Farms

Biannual recalibration of two spectral gamma-ray logging systems used for baseline characterization measurements in the Hanford Tank Farms. Vadose Zone Characterization Project at the Hanford Tank Farms

Date: May 1, 1996
Creator: Koizumi, C.J.
Description: The US Department of Energy`s (DOE`s) Grand Junction Projects Office (GJPO) is engaged in establishing an initial, or baseline, characterization of the gamma-ray-emitting contaminants in the subsurface of the Tank Farms at the DOE Hanford site in the State of Washington. These baseline data are gathered by logging existing monitoring boreholes with two high-resolution passive gamma-ray logging systems informally known as Gamma 1 and Gamma 2. Calibration of the logging systems is crucial to the assurance of data quality. The project document Spectral Gamma-Ray borehole Geophysical Logging Characterization and Baseline Monitoring Plan for the Hanford Single-Shell Tanks (DOE 1995a) specifies that the initial, or base, calibration of both systems must be performed before commencement of field measurements at Hanford and that both systems must be recalibrated every 6 months thereafter using the calibration standards at the Hanford borehole logging calibration center. Data collection for the base calibrations was completed in April 1995; the results were published in Calibration of Two Spectral Gamma-Ray Logging Systems for Baseline Characterization Measurements in the Hanford Tank Farms (DOE 1995b). This report documents the first recalibration of the two systems that was performed in October 1995 at the Hanford Site. Analyses of data collected during ...
Contributing Partner: UNT Libraries Government Documents Department
Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, July 1, 1992--September 30, 1992

Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, July 1, 1992--September 30, 1992

Date: November 13, 1992
Creator: Anthony, R.G. & Akgerman, A.
Description: A series of zirconia catalysts prepared by a modified sol gel procedure, coprecipitation with ammonium hydroxide, and by a hydrothermal method were evaluated for catalytic activity. These catalysts were prepared containing silicon, thorium, titanium, cerium and the alkali metals. A catalyst containing 2% thorium on zirconia was the most active. The isobutylene and isobutane selectivity were 19.4 wt % and 1.82 wt %, respectively. Macro- and micro-kinetic models indicate that C0{sub 2} formation inhibits the rate of CO conversion, hydrogen is dissociatively adsorbed, and CO is molecularly adsorbed. The microkinetic model indicates the strengthening of the metaloxygen bond might increase the production rate of isobutylene.
Contributing Partner: UNT Libraries Government Documents Department
Acrylic vessel cleaning tests

Acrylic vessel cleaning tests

Date: February 26, 1997
Creator: Earle, D.; Hahn, R.L.; Boger, J. & Bonvin, E.
Description: The acrylic vessel as constructed is dirty. The dirt includes blue tape, Al tape, grease pencil, gemak, the glue or residue form these tapes, finger prints and dust of an unknown composition but probably mostly acrylic dust. This dirt has to be removed and once removed, the vessel has to be kept clean or at least to be easily cleanable at some future stage when access becomes much more difficult. The authors report on the results of a series of tests designed: (a) to prepare typical dirty samples of acrylic; (b) to remove dirt stuck to the acrylic surface; and (c) to measure the optical quality and Th concentration after cleaning. Specifications of the vessel call for very low levels of Th which could come from tape residues, the grease pencil, or other sources of dirt. This report does not address the concerns of how to keep the vessel clean after an initial cleaning and during the removal of the scaffolding. Alconox is recommended as the cleaner of choice. This acrylic vessel will be used in the Sudbury Neutrino Observatory.
Contributing Partner: UNT Libraries Government Documents Department
Research in actinide chemistry. Final report, March 1, 1993--February 28, 1996

Research in actinide chemistry. Final report, March 1, 1993--February 28, 1996

Date: January 1, 1997
Creator: Choppin, G.R.
Description: The present three-year grant period has been a fruitful one for the laboratory as research entered some new areas while continuing in others in which the group has been successful. As in past grant periods, the principal focus has been on complexation of actinide elements with inorganic and organic ligands. The ligands to study have been chosen for their value (known or potential) in actinide separations or for their potential role in environmental behavior of the actinides. Since the radioactivity of some actinides limits the variety of techniques which can be used in their study, we have used {open_quotes}oxidation state analogs{close_quotes}. These analogs have the same oxidation state and very similar chemical behavior but are stable or very long-lived. Also, the analogs are chosen for their redox stability to avoid uncertainties in interpretation of systems in which several oxidations may coexist (e.g., in the case of Pu). Examples of such analogs which we have used are: Nd(III), Eu(III) for Pu(III), Am(III), Cm(III); Th(IV) for U(IV), Pu(IV); NpO{sub 2}{sup +} for PuO{sub 2}{sup +}; UO{sub 2}{sup 2+} for NpO{sub 2}{sup 2+}, PuO{sub 2}{sup 2+}. These analogs have allowed use of techniques which can increase significantly our understanding of actinide complexation.
Contributing Partner: UNT Libraries Government Documents Department
Isotope Trace Studies of Diffusion in Silicates and of Geological Transport Processes Using Actinide Elements

Isotope Trace Studies of Diffusion in Silicates and of Geological Transport Processes Using Actinide Elements

Date: January 19, 2001
Creator: Wasserburg, Prof. G. J.
Description: Over the past year we have competed two studies of Os concentration and isotopic composition in rivers from the Himalayan uplift and in hydrothermal fluids from the Juan de Fuca Ridge. Both of these studies have been published. We have completed a study of paleo-climate in Soreq Cave, Israel, and have expanded our studies of the transport of U-Th through riverine and estuarine environments. We are completing two studies of weathering and transport in the vadose in two very different environments--one a tropical regime with a deep laterite profile and the other a northern arboreal forest with only a thin weathering zone. We have begun a new study of U-Th in aquifers with low water velocity.
Contributing Partner: UNT Libraries Government Documents Department
Aqueous biphasic extraction of uranium and thorium from contaminated soils. Final report

Aqueous biphasic extraction of uranium and thorium from contaminated soils. Final report

Date: July 1, 1995
Creator: Chaiko, D.J.; Gartelmann, J.; Henriksen, J.L.; Krause, T.R.; Deepak; Vojta, Y. et al.
Description: The aqueous biphasic extraction (ABE) process for soil decontamination involves the selective partitioning of solutes and fine particulates between two immiscible aqueous phases. The biphase system is generated by the appropriate combination of a water-soluble polymer (e.g., polyethlene glycol) with an inorganic salt (e.g., sodium carbonate). Selective partitioning results in 99 to 99.5% of the soil being recovered in the cleaned-soil fraction, while only 0.5 to 1% is recovered in the contaminant concentrate. The ABE process is best suited to the recovery of ultrafine, refractory material from the silt and clay fractions of soils. During continuous countercurrent extraction tests with soil samples from the Fernald Environmental Management Project site (Fernald, OH), particulate thorium was extracted and concentrated between 6- and 16-fold, while the uranium concentration was reduced from about 500 mg/kg to about 77 mg/kg. Carbonate leaching alone was able to reduce the uranium concentration only to 146 mg/kg. Preliminary estimates for treatment costs are approximately $160 per ton of dry soil. A detailed flowsheet of the ABE process is provided.
Contributing Partner: UNT Libraries Government Documents Department
EVALUATIONS OF RADIONUCLIDES OF URANIUM, THORIUM, AND RADIUM ASSOCIATED WITH PRODUCED FLUIDS, PRECIPITATES, AND SLUDGES FROM OIL, GAS, AND OILFIELD BRINE INJECTION WELLS IN MISSISSIPPI

EVALUATIONS OF RADIONUCLIDES OF URANIUM, THORIUM, AND RADIUM ASSOCIATED WITH PRODUCED FLUIDS, PRECIPITATES, AND SLUDGES FROM OIL, GAS, AND OILFIELD BRINE INJECTION WELLS IN MISSISSIPPI

Date: March 1, 2004
Creator: Swann, Charles; Matthews, John; Ericksen, Rick & Kuszmaul, Joel
Description: Naturally occurring radioactive materials (NORM) are known to be produced as a byproduct of hydrocarbon production in Mississippi. The presence of NORM has resulted in financial losses to the industry and continues to be a liability as the NORM-enriched scales and scale encrusted equipment is typically stored rather than disposed of. Although the NORM problem is well known, there is little publically available data characterizing the hazard. This investigation has produced base line data to fill this informational gap. A total of 329 NORM-related samples were collected with 275 of these samples consisting of brine samples. The samples were derived from 37 oil and gas reservoirs from all major producing areas of the state. The analyses of these data indicate that two isotopes of radium ({sup 226}Ra and {sup 228}Ra) are the ultimate source of the radiation. The radium contained in these co-produced brines is low and so the radiation hazard posed by the brines is also low. Existing regulations dictate the manner in which these salt-enriched brines may be disposed of and proper implementation of the rules will also protect the environment from the brine radiation hazard. Geostatistical analyses of the brine components suggest relationships between the concentrations of ...
Contributing Partner: UNT Libraries Government Documents Department
ASSESSMENT OF LIQUID EMULSION MEMBRANE FOR CLEAN UP OF AQUEOUS WASTE EFFLUENTS FROM HAZARDOUS ELEMENTS

ASSESSMENT OF LIQUID EMULSION MEMBRANE FOR CLEAN UP OF AQUEOUS WASTE EFFLUENTS FROM HAZARDOUS ELEMENTS

Date: February 27, 2003
Creator: El-Reefy, Sohair A.; Selim, Y.T.; Hassan, M.A. & Aly, H.F.
Description: Four liquid emulsion membrane (LEM) systems are given to remove different hazardous elements such as uranium, thorium, cobalt, copper, lead, and cadmium from different aqueous waste effluents. The optimum conditions for use of these systems are deduced. The potentiality of LEM for removal of hazardous pollutants from aqueous waste solutions is given.
Contributing Partner: UNT Libraries Government Documents Department
Associating Physical and Chemical Properties to Evaluate Buffer Materials by Th and U Sorption

Associating Physical and Chemical Properties to Evaluate Buffer Materials by Th and U Sorption

Date: February 27, 2003
Creator: Jan, Yi-Lin; Chen, Tzu-Yun; Cheng, Hwai-Ping; Hsu, Chun-Nan; Tseng, Chia-Liang; Wei,Yuan-Yaw et al.
Description: The physical and chemical properties of buffer materials to be used for a radwaste disposal repository should be evaluated prior to use. In a conventional approach, independent studies of physical and/or chemical characteristics are conducted. This study investigated the relationship between the plastic index (PI) and distribution ratio (Rd) of buffer materials composed of varying ratios of quartz sand and bentonite. Thorium (Th) and Uranium (U) were the nuclides of interest, and both synthetic groundwater and seawater were used as the liquid phases to simulate conditions representative of deep geological disposal within an island. Atterberg tests were used to determine PI values, and batch sorption experiments were employed to measure Rd values. The results show that Th reached maximum sorption behavior when the bentonite content exceeded 30 % of the mixture. Contrariwise, the sorption of U increased linearly with bentonite content, up to bentonite contents of 100%, and this correlation was present regardless of the liquid phase used. A further result is that U has a better additivity with respect to Rd than Th in both synthetic groundwater and synthetic seawater. These results will allow a determination of more effective buffer material composition, and improved estimates of the overall Rd ...
Contributing Partner: UNT Libraries Government Documents Department
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