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Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910: Part 1. -- Analyses (open access)

Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910: Part 1. -- Analyses

From Significance and value of Analyses of Coal: "The analyses published in this report cover samples of coal collected in many different parts of the country with unusual care by experiences men, in such manner as to make them representative of extensive beds of coal."
Date: 1913
Creator: Lord, N. W.
System: The UNT Digital Library
Hyatt Rach Pegmatite, Larimer County, Colorado (open access)

Hyatt Rach Pegmatite, Larimer County, Colorado

Report issued by the Bureau of Mines over studies conducted on Larimer County pegmatite deposits. Descriptions of the deposits are presented. This report includes tables, maps, photographs, and illustrations.
Date: 1960
Creator: Gilkey, Millard M.
System: The UNT Digital Library
Extraction and Recovery of Mercury and Lead From Aqueous Waste Streams Using Redox-Active Layered Metal Chalcogenides. Annual Progress Report, September 15, 1996--September 14, 1997 (open access)

Extraction and Recovery of Mercury and Lead From Aqueous Waste Streams Using Redox-Active Layered Metal Chalcogenides. Annual Progress Report, September 15, 1996--September 14, 1997

'The authors have begun to examine the extraction and recovery of heavy elements from aqueous waste streams using redox-active metal chalcogenides. They have been able to prepare extractants from known chalcogenide starting materials, studied the efficacy of the extractants for selective removal of soft metal ions from aqueous phases, studied the deactivation of extractants and the concomitant recovery of soft metal ions from the extractants, and characterized all of the solids and solutions thus far in the study. The study was proposed as two parallel tasks: Part 1 and Part 2 emphasize the study and development of known metal chalcogenide extractants and the synthesis and development of new metal chalcogenide extractants, respectively. The two tasks were divided into sub-sections that study the extractants and their chemistry as detailed below: Preparation and reactivity of metal chalcogenide host solids Extraction of target waste (guest) ions from simulated waste streams Examination of the guest-host solids recovery of the guest metal and reuse of extractant Each section of the two tasks was divided into focused subsections that detail the specific problems and solutions to those problems that were proposed. The extent to which those tasks have been accomplished and the continued efforts of the …
Date: January 1, 1997
Creator: Dorhout, P.K. & Strauss, S.H.
System: The UNT Digital Library
Extraction and Recovery of Mercury and Lead From Aqueous Waste Streams Using Redox-Active Layered Metal Chalcogenides. 1998 Annual Progress Report (open access)

Extraction and Recovery of Mercury and Lead From Aqueous Waste Streams Using Redox-Active Layered Metal Chalcogenides. 1998 Annual Progress Report

'Mercury and other highly-toxic heavy metals such as cadmium and lead are present in many aquatic environments, and the remediation of such environments or the avoidance of heavy-metal contamination in the first place is an area of active interest. In recent years tougher environmental regulations and the high initial cost of new, more effective, and more selective extractants has made the reuse of extractant materials and the minimization of secondary waste volume a focus of their scientific effort. The authors research has involved the investigation of redox-active layered metal chalcogenides as selective, effective, and redox-recyclable extractants for heavy metals from aqueous solution.'
Date: June 1, 1998
Creator: Dorhout, P.K. & Strauss, S.H.
System: The UNT Digital Library
Long-Term Risk From Actinides in the Environment: Modes of Mobility. 1998 Annual Progress Report (open access)

Long-Term Risk From Actinides in the Environment: Modes of Mobility. 1998 Annual Progress Report

'The mobility of actinides in surface soils is a key issue of concern at several DOE facilities in arid and semiarid environments, including Rocky Flats, Hanford, Nevada Test Site, Idaho National Engineering Laboratory, and Los Alamos National Laboratory and the Waste Isolation Pilot Plant (WIPP). Key sources of uncertainty in assessing Pu mobility are the magnitudes of mobility resulting from three modes of transport: (1) wind erosion, (2) water erosion, and (3) vertical migration. Each of these three processes depend on numerous environmental factors and they compete with one another, particularly for actinides in very shallow soils ({approximately} 1 \265m). The overall goal of the study is to quantify the mobility of soil actinides from all three modes. The authors study is using field measurements, laboratory experiments, and ecological modeling to address these three processes at three DOE facilities where actinide kinetics are of concern: WIPP, Rocky Flats, and Hanford. Wind erosion is being measured with suite of monitoring equipment, water erosion is being studied with rainfall simulation experiments, vertical migration is being studied in controlled laboratory experiments, and the three processes are being integrated using ecological modeling. Estimates for clean up of soil actinides for the extensive tracts of …
Date: June 1, 1998
Creator: Breshears, D. D.; Whicker, J. J.; Ibrahim, S. A.; Whicker, F. W.; Hakonson, T. E. & Kirchner, T.
System: The UNT Digital Library
Detection of blockages in process piping Los Alamos National Laboratory. Final report (open access)

Detection of blockages in process piping Los Alamos National Laboratory. Final report

The attached reports and proposal summarize the work to date for the revised Ultrasonic Resonance Interferometry system. The most recent set of experiments, to determine the accuracy of the implementation of a new calibration curve to account for the variation of the wave speed with temperature, were never completed due to lack of funding. The general focus of the ongoing work, outlined in the weekly reports, had been improvements in accuracy of the measurement system using software modifications. The future focus of the project, as outlined in the attached proposal, was to incorporate a thermal conductivity probe with the ultrasonic measurement system to allow measurement of fluids which have a bimodal wavespeed vs. molarity relation.
Date: October 1, 1994
Creator: Histand, M.B.
System: The UNT Digital Library
National Institute for Global Environmental Change. Final Report (open access)

National Institute for Global Environmental Change. Final Report

Over the past decade or so the evolution and equilibria of persistent decks of stratocumulus climatologically clinging to the edge of summertime subtropical highs has been an issue of increased scientific inquiry. The particular interest in the microphysical structure of these clouds stems from a variety of hypotheses which suggest that anthropogenic influences or biogenic feedbacks may alter the structure of these clouds in a manner which may be climatically significant. Most hypotheses regarding boundary layer influences on climate have been formulated by an examination of the solution space of simple models. The earliest hypothesis of this sort (and the one on the most solid footing) is due to Twomey (1974), who posited that enhanced concentrations of CCN could lead to enhanced droplet reflectivity and enhanced albedos in clouds of modest optical depths. In low lying clouds where the albedo effect dominates, the climate sensitivity to a robust perturbation in cloud albedo may be significant. One of the primary objectives of this current research has been to explore the hypothesis of Twomey. The basic approach was to couple radiative calculations with detailed representations of the droplet spectra. The detailed representation of the droplet spectra was generated by the Large Eddy …
Date: March 9, 1995
Creator: Cotton, W.R.; Stevens, B.; Duda, D.; Richardson, W. & Feingold, G.
System: The UNT Digital Library
Catalytic applications of mono- and dinuclear complexes containing metal-carbon sigma bonds. Final report, November 1, 1993--October 31, 1996 (open access)

Catalytic applications of mono- and dinuclear complexes containing metal-carbon sigma bonds. Final report, November 1, 1993--October 31, 1996

This report discusses results from several studies involved in the project. Investigations include: vibrational models for surface olefins and alkylidenes; mechanism of the formation and fragmentation of diosmacyclobutanes; reaction of dienes and allenes with diosmacyclobutanes; determination by nematic phase NMR of the structure of mononuclear and dinuclear ethylene complexes of osmium; and generation of ``coordinatively unsaturated`` complexes by protonation of methyl osmium complexes.
Date: December 31, 1996
Creator: Norton, J.R.
System: The UNT Digital Library
Development of a kinetic model and calculation of radiation dose estimates for sodium iodide-{sup 131}I in athyroid individuals (open access)

Development of a kinetic model and calculation of radiation dose estimates for sodium iodide-{sup 131}I in athyroid individuals

The treatment for some thyroid carcinomas involves surgically removing the thyroid gland and administering the radiopharmaceutical Sodium iodide-{sup 131}I (NaI). A diagnostic dose of NaI is given to the patient to determine if remnant tissue from the gland remains or larger doses are administered in order to treat the malignant tissue. Past research regarding NaI uptake and retention in euthyroid individuals (normal functioning thyroid) reveal that radioiodine concentrates mainly in the thyroid tissue and the remaining material is excreted from the body. The majority of radioiodine in athyroid (without thyroid) individuals is also eliminated from the body; however, there has been recent evidence of a long-term retention phase for individuals with no radioiodine concentrating tissue. The general purpose of this study was to develop a kinetic model and estimate the absorbed dose to athyroid individuals regarding the distribution and retention of NaI.
Date: July 1, 1997
Creator: Rodriguez, M.
System: The UNT Digital Library
Exploratory Study of Metal Vapor Lasers Operating in the Ultra-Violet at Kilowatt Power Levels. Technical Progress Report, June 1, 1975--May 1, 1976 (open access)

Exploratory Study of Metal Vapor Lasers Operating in the Ultra-Violet at Kilowatt Power Levels. Technical Progress Report, June 1, 1975--May 1, 1976

Three laser research programs are proposed: (1) to find new laser systems in the wavelength region between 2000 and 4500 A; (2) to attempt scaling lasers to high output power; and (3) to focus research on metal vapor laser systems which have promise of high efficiency. Twenty-eight new laser transitions from Cu II spanning the wavelength region from 2486 to 7988 A have been observed. A list of papers and conferences are given that summarize the metal vapor laser research. (TFD)
Date: March 1, 1976
Creator: Collins, G.J.
System: The UNT Digital Library
Exploration of the Big Boulder Prospect, Larimer County, Colorado (open access)

Exploration of the Big Boulder Prospect, Larimer County, Colorado

From introduction: The Big Boulder prospect is in SE 1/4 sec. 36, T.7N., R.,72W., in Tarimer County, Colorado. The prospect has been opened by four irregular trenches and shallow cuts, and a 10-foot discovery shaft. Hanley 1/4 states that 10.5 tons of beryl were produced from the Big Boulder prospect in 1936, and about 600 pounds in 1941.
Date: August 1950
Creator: Thurston, W. R.
System: The UNT Digital Library
Pegmatites of the Crystal Mountain District, Larimer County, Colorado (open access)

Pegmatites of the Crystal Mountain District, Larimer County, Colorado

From abstract: The Front Range of Colorado is composed chiefly of schists of the Idaho Springs formation of pre-Cambrian age which have been intruded by a variety of granitic batholiths. In the Crystal Mountain district the Mount Olympus granite, a satellite of Fuller's Longs Peak batholith, forms sills and essentially concordant multiple intrusions in quartz-mica schist that dips southward at moderate to steep angles. A great number of pegmatites accompanied and followed the intrusion of the sills and formed concordant and discordant bodies in schist and granite.
Date: 1955
Creator: Thurston, William R.
System: The UNT Digital Library
Treasure Hill Area, Larimer County, Colorado (open access)

Treasure Hill Area, Larimer County, Colorado

Abstract: The Treasure Hill area consists of eight mining-lode claims in secs. 10 and 15, T. 9 N., R. 70 W., Larimer County, Colo. All of the workings were examined and samples were taken from most of them. The results of the examination indicate that there is little or no detectable radioactivity in the schist and granite of the area.
Date: December 20, 1951
Creator: Wyant, Donald G.
System: The UNT Digital Library
Pegmatites of the Crystal Mountain District, Larimer County, Colorado (open access)

Pegmatites of the Crystal Mountain District, Larimer County, Colorado

From introduction: The study of the Crystal Mountain district, Larimer County, Colo., is but one phase of this post-World War II pegmatite program, in part carried out by the Geological Survey on behalf of the Division of Raw Materials of the Atomic Energy Commission.
Date: April 1952
Creator: Thurston, William R.
System: The UNT Digital Library
Generalized Altitude and Configuration of the Water Table in Parts of Larimer, Logan, Sedgwick, and Weld Counties, Colorado (open access)

Generalized Altitude and Configuration of the Water Table in Parts of Larimer, Logan, Sedgwick, and Weld Counties, Colorado

From introduction: The purpose of this study was to define the altitude and configuration of the water table for use by water planners and users in future development of water resources.
Date: 1983
Creator: Borman, R. G. & Gaggiani, Neville G.
System: The UNT Digital Library
Ground-Water Resources of the Alluvial Aquifers in Northeastern Larimer County, Colorado (open access)

Ground-Water Resources of the Alluvial Aquifers in Northeastern Larimer County, Colorado

From introduction: Ground water is a source of municipal, domestic, stock, and irrigation water supply for most of northeastern Larimer County, Colorado. This report presents the results of a study made to determine the quantity, availability, and quality of the ground water. This information should be useful particularly for land-use planning and the utilization and protection of the ground-water resources.
Date: January 1977
Creator: Hurr, R. Theodore & Schneider, Paul A., Jr.
System: The UNT Digital Library
Shallow Ground Water in the Boulder-Fort Collins-Greeley Area, Front Range Urban Corridor, Colorado, 1975-77 (open access)

Shallow Ground Water in the Boulder-Fort Collins-Greeley Area, Front Range Urban Corridor, Colorado, 1975-77

From introduction: This investigation was made as part of a comprehensive geohydrologic study of the Front Range Urban Corridor in Colorado conducted by the U.S. Geological Survey. The purpose of the study was to delineate the areal extent of the aquifer, the altitude and configuration of the water table, and the gradient and underflow in various parts of the area, in order to better understand the quality of water moving into and through the aquifer.
Date: 1983
Creator: Schneider, Paul A., Jr.
System: The UNT Digital Library
Geology of the Copper King Mine Area, Prairie Divide, Larimer County, Colorado (open access)

Geology of the Copper King Mine Area, Prairie Divide, Larimer County, Colorado

Report discussing the geology of the Copper King mine area, which was worked for uranium following the discovery of pitchblende. The geology of the site is described as well as the history of the area's production.
Date: December 1952
Creator: Sims, Paul K. & Phair, George
System: The UNT Digital Library
Pegmatites of the Crystal Mountain District, Larimer County, Colorado (open access)

Pegmatites of the Crystal Mountain District, Larimer County, Colorado

Report discussing the geology of the pegmatites in the Crystal Mountain district in Larimer County, Colorado.
Date: April 1952
Creator: Thurston, William R.
System: The UNT Digital Library
Design, Construction, and Testing of a Residential Solar Heating and Cooling System. Progress Report, 1 September 1973--31 January 1974 (open access)
Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination] (open access)

Palladium Catalyzed Coupling Reactions: Mechanism of Reductive Elimination. Progress Report, October 1, 1979-September 30, 1980. [Ethane Elimination]

The 1,1-reductive elimination of ethane from three cis-bis(phosphine)-dimethylpalladium complexes, L/sub 2/Pd(CH/sub 3/)/sub 2/ (L = PPh/sub 3/, PPh/sub 2/,CH/sub 3/ and L/sub 2/ = Ph/sub 2/PCH/sub 2/CH/sub 2/PPh/sub 2/), and three trans analogs (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/ and L/sub 2/ = 2,11-bis(diphenylphosphinomethyl)benzo(c)phenanthrene (TRANSPHOS)) was carried out. The three cis complexes underwent reductive elimination in the presence of coordinating solvents (DMSO, DMF, and THF). The trans complexes which could isomerize to cis (L = PPh/sub 3/, PPh/sub 2/CH/sub 3/) did so in polar solvents and then underwent reductive elimination. TRANSPHOS dimethylpalladium would not undergo reductive elimination of ethane. The eliminations from the cis isomers were intramolecular and displayed first order kinetics. Although TRANSPHOS dimethylpalladium(II) would not undergo a 1,1-reductive elimination of ethane, the addition of CD/sub 3/I to a DMSO solution of this complex at 25/sup 0/C rapidly produced CD/sub 3/-CH/sub 3/, implicating a transient palladium(IV) intermediate. E- and Z-bromostyrylbis(diphenylmethylphosphine)palladium(0) react with methyl lithium in THF at ambient temperature to give the E- and Z- propenylbenzenes, respectively. At -78/sup 0/C, the intermediate E- and Z-styrylmethylbis(diphenylmethylphosphine)palladium(II) complexes (9a,b) can be isolated. On raising the temperature of solutions of 9a,b in THF, E- and Z-propenylbenzenes are produced. The reductive elimination …
Date: September 1, 1980
Creator: Stille, J. K.
System: The UNT Digital Library
Planetary-Wave Behavior and Arctic Air Pollution (open access)

Planetary-Wave Behavior and Arctic Air Pollution

An attempt was made to relate episodes of air pollution at Barrow, Alaska, containing vanadium, to the behavior of planetary waves in middle and high latitudes. A stationarity index for planetary waves is defined as the ratio between amplitudes computed from monthly mean maps and the mean amplitudes computed on a daily basis and averaged over the same month, irrespective of phase angle. Longitude-time sections of 500-mb height anomalies at various latitudes are related to vanadium pollution episodes at Barrow.
Date: January 1, 1979
Creator: Reiter, Elmar R.
System: The UNT Digital Library
Novel Concepts in Electrochemical Solar Cells. Second Quarterly Progress Report, August 15, 1979-October 15, 1979. [Molten Salt Electrolytes] (open access)

Novel Concepts in Electrochemical Solar Cells. Second Quarterly Progress Report, August 15, 1979-October 15, 1979. [Molten Salt Electrolytes]

It is considered that the short term stability of n-GaAs PEC's in a ferrocene-based, ambient temperature molten salt electrolyte is reasonably good. However, longer term evaluation is required to determine the extent and significance of corrosion, stability, etc. Extremely few fundamental studies have been made of the semiconductor/molten salt interphase and experiments in this area would be most useful. Indeed, even the design parameters for PECs of any kind have not been quantitatively delineated and present consideration will be given to models for PEC solar cells and limitations caused by ion transport in the electrolyte. The MoSe/sub 2/ and MoS/sub 2/ electrodes appear to have substrate reproducibility and transport limitations that make them unsuitable candidates for efficient PEC's at this time. Similarly, the lack of availability of high quality CuInSe/sub 2/ and CuInS/sub 2/ substrates limits the quantitative experimental evaluation of their utility for PEC applications. We are presently focusing attention on CdSe/CdTe mixtures and CdS as electrodes as well as Si and GaAs in molten salt and polyelectrolyte solutions. The system for solar cell evaluation and network analysis of substrates and cells was mode operational. Preliminary work on economic and theoretical modelling was begun. Progress is reported. (WHK)
Date: January 1, 1979
Creator: DuBow, J.; Job, R.; Krishnan, R. & Gale, B.
System: The UNT Digital Library
Effects of Vegetation on Radon Transport Processes in Soil (open access)

Effects of Vegetation on Radon Transport Processes in Soil

A large component of radon entry cannot be explained by pressure differences between the soil and inside the structures. The persistence of this radon entry even when the house is pressurized by 1 Pa indicates that it must be due to molecular diffusion. The radon entry rate as measured by accumulators below ground level (soil + concrete) is roughly 2 times greater than that measured above ground level (concrete alone). The soil permeability is about 10{sup {minus}12} m{sup 2} and does not change dramatically with depth down to 2 m. The diffusion component of radon entry is reduced by about 30% when the floor wall joint is sealed. The Rn3D model is operating on our computer system and is being modified to accommodate the geometrical configurations of the underground test structure.
Date: January 1, 1991
Creator: Borak, T.B.
System: The UNT Digital Library