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United States Geological Survey Reports
12
Trace elements investigations report
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Water Resources Investigations Reports
3
United States Bureau of Mines Reports
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Geological Survey professional paper
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Report of investigations (United States. Bureau of Mines)
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Role of polycrystallinity in CdTe and CuInSe[sub 2] photovoltaic cells
The limiting role of polycrystallinity in thin-film solar calls has been reduced somewhat during the past year, and efficiencies of both CdTe and CuInSe[sub 2] cells are approaching 15%. Quantitative separation of loss mechanisms shows that individual losses, with the exception of forward recombination current, can be made comparable to their single crystal counterparts. One general manifestation of the extraneous trapping states in that the voltage of all polycrystalline thin-film cells drifts upward by 10--50 mV following the onset of illumination.
Date:
November 1, 1992
Creator:
Sites, J.R. (Colorado State Univ., Fort Collins, CO (United States))
System:
The UNT Digital Library
Parameterization of Convective Clouds Mesoscale Convective Systems, and Convective-Generated Cirrus. Final Report, September 15, 1990--October 31, 1993
The overall goal of this research is to develop a scheme to parameterize diabatic heating, moisture/water substance, and momentum transports, and precipitation from mesoscale convective systems (MCSs) for use in general circulation models (GCMs). Our approach is to perform explicit cloud-resolving simulations of MCSs in the spirit of the GEWEX Cloud Systems Study (GCSS), by using the Regional Atmospheric Modeling System (RAMS) developed at Colorado State University (CSU). We then perform statistical analyses (conditional sampling, ensemble-averages, trajectory analyses) of simulated MCSs to assist in fabricating a parameterization scheme, calibrating coefficients, and provide independent tests of the efficacy of the parameterization scheme. A cloud-resolving simulation of ordinary cumulonimbi forced by sea breeze fronts has been completed. Analysis of this case and comparison with parameterized convection simulations has resulted in a number of refinements in the scheme. Three three-dimensional, cloud-resolving simulations of MCSs have been completed. Statistical analyses of model-output data are being performed to assist in developing a parameterization scheme of MCSs in general circulation models.
Date:
November 5, 1993
Creator:
Cotton, W. R.
System:
The UNT Digital Library
Role of polycrystallinity in CdTe and CuInSe{sub 2} photovoltaic cells. Annual subcontract report, 1 April 1990--31 March 1991
The polycrystalline nature of thin-film CdTe and CuInSe{sub 2} solar cells continues to be a major factor in several individual losses that limit overall cell efficiency. This report describes progress in the quantitative separation of these losses, including both measurement and analysis procedures. It also applies these techniques to several individual cells to help document the overall progress with CdTe and CuInSe{sub 2} cells. Notably, CdTe cells from Photon Energy have reduced window photocurrent losses to 1 mA/Cm{sup 2}; those from the University of South Florida have achieved a maximum power voltage of 693 mV; and CuInSe{sub 2} cells from International Solar Electric Technology have shown a hole density as high as 7 {times} 10{sup 16} cm{sup {minus}3}, implying a significant reduction in compensation. 9 refs.
Date:
December 31, 1991
Creator:
Sites, J. R.
System:
The UNT Digital Library
Advanced NMR approaches in the characterization of coal. Final technical report, September 1, 1990--August 31, 1993
This project addressed two main goals and one much smaller one. The main goals were (1) to improve the significance, reliability and information content in high-resolution NMR (nuclear magnetic resonance) characterization of coal samples and (2) to develop chemically informative NMR imaging techniques for coal. The minor goal was to explore advanced features of dynamic nuclear polarization (DNP) as a technique for coal characterization; this included the development of two DNP probes and the examination of DNP characteristics of various carbonaceous samples, including coals. {sup 13}C NMR advances for coal depended on large-sample MAS devices, employing either cross-polarization (CP) or direct polarization (DP) approaches. CP and DP spin dynamics and their relationships to quantitation and spin counting were elucidated. {sup 1}H NMR studies, based on CRAMPS, dipolar dephasing and saturation with perdeuteropyridine, led to a {sup 1}H NMR-based elucidation of chemical functionality in coal. {sup 1}H and {sup 13}C NMR imaging techniques, based on magic-angle spinning and rotating magnetic field gradients, were developed for introducing chemical shift information (hence, chemical detail) into the spatial imaging of coal. The TREV multiple-pulse sequence was found to be useful in the {sup 1}H CRAMPS imaging of samples like coal.
Date:
September 30, 1993
Creator:
Maciel, G. E.
System:
The UNT Digital Library
Evaluation of Aftermarket Fuel Delivery Systems for Natural Gas and Lpg Vehicles
This study was designed to evaluate the effectiveness of aftermarket fuel delivery systems for vehicles fueled by compressed natural gas (CNG) and liquefied petroleum gas (LPG). Most of the CNG and LPG vehicles studied were converted to the alternative fuel after purchase. There are wide variations in the quality of the conversion hardware and the installation. This leads to questions about the overall quality of the converted vehicles, in terms of emissions, safety, and performance. There is a considerable body of emissions data for converted light-duty vehicles, and a smaller amount for medium- and heavy-duty vehicles. However, very few of these data involve real world conditions, and there is growing concern about in-use emissions. This report also attempts to assess factors that could allow in-use emissions to vary from the best-case'' results normally reported. The study also addresses issues of fuel supply, fuel composition, performance, safety, and warranty waivers. The report is based on an extensive literature and product survey and on the author's experience with fuel delivery systems for light-duty vehicles.
Date:
September 1, 1992
Creator:
Willson, B. (Colorado State Univ., Fort Collins, CO (United States))
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
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
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
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
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
Report of factual data obtained during examination of Copper King shaft, Black Hawk claim no. 1, Larimer County, Colorado
A report regarding factual data obtained during an examination of the copper King Shaft, Black Hawk Claim no. 1, Larimer County, Colorado. This report is designed to provide the owners with the factual data obtained from their property in accordance with the Agreement for Mineral Exploration with them.
Date:
May 1950
Creator:
Granger, H. C. & King, Robert Ugstad
System:
The UNT Digital Library
Geology of the Copper King Mine area, Prairie Divide, Larimer County, Colorado
"This report, prepared principally to aid in the interpretation of the core drilling, presents the principal results of the field and preliminary laboratory work by the U.S. Geological Survey; it does not contain information obtained from the core drilling."
Date:
December 1952
Creator:
Sims, P. K. & Phair, George
System:
The UNT Digital Library
Geology of the Copper King uranium mine, Larimer County, Colorado
A report regarding the geology of the Copper King Uranium Mine, in Larimer County, Colorado.
Date:
June 1955
Creator:
Sims, P. K.; Phair, George & Moench, Robert Hadley
System:
The UNT Digital Library
Cross-Spectral Study of the Spatial Relationships in the North Pacific Sea-Surface Temperature Anomaly Field. Report No. 23
Cross-spectral analysis is used to examine the dependence of the temporal covariation of sea-surface temperature (SST) anomalies at pairs of spatially separated points in the North Pacific on (1) the time scale of the variations, (2) the relative displacement of the points and (3) their location within the North Pacific basin. Spatial scales considered here range from 1000 kilometers up to the width of the basin. The study focuses on cross-spectral estimates for the interannual frequency band, 0.125-0.75 yr/sup -1/ although estimates for three other bands spanning higher frequencies are also examined.
Date:
March 1, 1980
Creator:
Middleton, John W.
System:
The UNT Digital Library
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
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
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
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
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
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
'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