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United States Geological Survey Reports
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Geological Survey professional paper
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A Preliminary Improved Test of the Flavor Independence of Strong Interactions
The authors present an improved comparison of the strong couplings of gluons to light (u, d, and s), c, and b quarks, determined from multijet rates in flavor-tagged samples of hadronic Z{sup 0} decays recorded with the SLC Large Detector at the SLAC Linear Collider between 1993 and 1995. Flavor separation on the basis of lifetime and decay multiplicity differences among hadrons containing light, c, and b quarks was made using the SLD precision tracking system, yielding tags with high purity and low bias against {ge} 3-jet final states. They find: {alpha}{sub s}{sup uds}/{alpha}{sub s}{sup all} = 0.997 {+-} 0.011(stat) {+-} 0.011(syst) {+-} 0.005(theory), {alpha}{sub s}{sup c}/{alpha}{sub s}{sup all} = 0.984 {+-} 0.042 {+-} 0.053 {+-} 0.022, {alpha}{sub s}{sup b}/{alpha}{sub s}{sup all} = 1.022 {+-} 0.019 {+-} 0.023 {+-} 0.012.
Date:
June 1, 1997
Creator:
Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Object Type:
Article
System:
The UNT Digital Library
Production of {pi}{sup {+-}}, K{sup {+-}}, K{sup 0}, K*{sup 0}, {phi}, p and {Lambda}{sup 0} in Hadronic Z{sup 0} Decays
The authors have measured production rates as a function of momentum of the identified hadrons {pi}{sup +}, K{sup +}, K{sup 0}, K*{sup 0}, {phi}, p, {Lambda}{sup 0} and their antihadrons in inclusive hadronic Z{sup 0} decays, as well as separately in decays into light, c and b flavors. In addition they have compared hadron and antihadron production rates in light quark (rather than antiquark) jets. The SLD Cherenkov Ring Imaging Detector was used to identify charged hadrons. The vertex detector was used to tag high-purity samples of light- and b-flavor events. The electron beam polarization was used to tag samples of quark and antiquark jets. Clear flavor dependences are observed, consistent with expectations based upon measured production and decay properties of heavy hadrons. They use the light-flavor results to test the predictions of MLLA QCD and of various fragmentation models. Differences between hadron and antihadron production in light quark jets are observed at high momentum fraction, providing direct evidence that higher-momentum particles are more likely to contain a primary quark or antiquark, and they use these results to make a new direct measurement of strangeness suppression in the jet fragmentation process.
Date:
June 1, 1997
Creator:
Abe, K.; Abe, K.; Akagi, T. & Collaboration, SLD
Object Type:
Article
System:
The UNT Digital Library
The production of {pi}{sup {+-}}, K{sup {+-}}, p, k{sup 0} and {Lambda}{sup 0} in hadronic Z{sup 0} decays
The authors have measured production fractions and spectra for {pi}{sup {+-}}, K{sup {+-}} and p, and production spectra for K{sup 0} and {Lambda}{sup 0} in both hadronic Z{sup 0} decays and a Z{sup 0} {yields} light quark (uds) subset at SLD. The SLD Cherenkov Ring Imaging Detector was used to identify charged hadrons. The CCD vertex detector was used to select the enriched uds sample. For the global sample, the results are consistent with previous experiments. The authors observe a clear flavor dependence in production spectra, but only a small effect in hadron fractions and {xi} = ln(1/x{sub p}) peak positions.
Date:
August 1, 1995
Creator:
Baird, K.
Object Type:
Article
System:
The UNT Digital Library
Effects of Vegetation of Radon Transport Processes in Soil: The Origins and Pathways of {Sup 222}Rn Entering Into Basement Structures. Final Report, March 15, 1987--May 15, 1993
The entry rate of {sup 22}Rn into a basement structure was measured continuously. These measurements demonstrated that radon entry did not vanish even when the structure was slightly pressurized. This persistent entry has been determined to be dominated by diffusion through the floor and walls and a combination of diffusion and convection through the floor-wall joint. The highest indoor radon concentrations occurred during calm periods when the pressure differentials between the inside and outside of the structure were small. The objectives of this work were to identify the origins of the radon and investigate the entry pathways. The radon could originate either in the concrete or in the soil surrounding the structure. Entry pathways into the basement were through the concrete floor and walls as well as through the floor-wall joint. The contributions of the origins and entry pathways were determined by continuously measuring the radon entry rate into the basement, using a trace gas system, and the flux density through portions of the floor and walls. Radon entry through the floor-wall joint could be controlled using a baseboard barrier system. Results indicated that, during calm conditions with wind speeds less than 1 m s{sup {minus}1}, 25 % of the …
Date:
August 1, 1992
Creator:
Borak, T. B.
Object Type:
Report
System:
The UNT Digital Library
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.
Object Type:
Report
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.
Object Type:
Report
System:
The UNT Digital Library
VXD3: The SLD Vertex Detector Upgrade Based on a 307 MPixel CCD System
The SLD upgrade CCD vertex detector (VXD3) is described. Its 307 million pixels are assembled from 96 3.2 Mpixel CCDs of 13 cm{sup 2} each. The system has evolved from the pioneering CCD vertex detector VXD2, which has operated in SLD since 1992. The CCDs of VXD3 are mounted on beryllium ladders in three cylinders, providing three space point measurements along each track of about 5 microns resolution in all three co-ordinates. Significant improvements are achieved with VXD3 in impact parameter resolution (about a factor of two) and acceptance ({approximately}20%) through optimized geometry and reduced material. New readout electronics have been developed for this system.
Date:
December 1995
Creator:
Brau, James E.
Object Type:
Article
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.
Object Type:
Report
System:
The UNT Digital Library
Variability Within the Ocean-Atmospheric System Over the North Pacific
Characteristics of the oceanic mixed layer over the North Pacific were examined utilizing a number of statistical methods. Based on the analyses of twelve years of data, a quasi-meridional differentiation (QMD) in sea surface temperature (SST) spectra across the North Pacific was observed. The SST spectra became increasingly red as an increasing function of latitude. A strong 21 to 26 day cycle in SST anomalies is discussed which may be a reflection of heat fluxes. These fluxes also vacillate significantly on this time-scale in conjunction with cycles observed in the atmospheric energy modes of available potential and kinetic energy. Examination of an oceanic heat budget on a spatial and temporal basis suggest that the impact of latent and sensible heat fluxes upon ..delta..SST is partially a function of the magnitude of the heat fluxes as well as of the depth to which their effects are mixed. The heat budget analyses and the fitting of power spectra of SST anomalies over the North Pacific to a two-parameter oceanic model, suggest that SST behavior over the mid-oceanic regions of the North Pacific is dominated by the influence of latent and sensible heat fluxes. On the other hand, over the remainder of the …
Date:
January 1, 1980
Creator:
Ciesielski, P E
Object Type:
Report
System:
The UNT Digital Library
Exploratory Study of Metal Vapor Lasers Operating in the Ultra-Violet at Kilowatt Power Levels. Final Report, June 1, 1975--March 31, 1979
Cw laser action has been extended down to 220 nm. Moreover, cw oscillation has been obtained on twenty additional transitions in the spectral range between 220 and 320 nm. Ultra-violet laser thresholds as low as 2 A have been observed. In comparison, rare gas ion lasers require 20 to 50 A to reach threshold. Metals of interest are sputtered into the discharge giving metal densities of 10/sup 14/ atoms cm/sup -3/ without using external ovens or discharge heating. Recent attempts to scale the output power levels to 1 W cw are presented with particular emphasis on the 780 nm transitions of Cu II and the 840 nm transitions of Ag II.
Date:
March 1, 1979
Creator:
Collins, G.J.
Object Type:
Report
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.
Object Type:
Report
System:
The UNT Digital Library
Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report
Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in the Corning design, whereas heat is conducted through a single glass wall to an external heat exchanger plate in the Philips collector. In comparison with conventional flat-plate collectors, both types show reduced heat losses and improved efficiency. For space heating and hot water supply in winter, the solar delivery efficiency of the Corning collector ranged from 49% to 60% of the incident solar energy. The portion of the space heating and domestic hot water load carried by solar energy through fall and winter ranged from 50% to 74%, with a four-month contribution of 61% of the total requirements. Data on the Philips collector are currently being analyzed.
Date:
January 1, 1979
Creator:
Conway, T. M.; Duff, W. S.; Loef, G. O. G. & Pratt, R. G.
Object Type:
Article
System:
The UNT Digital Library
Rehabilitation Potential and Practices of Colorado Oil Shale Lands. Progress Report, June 1, 1978--May 31, 1979
The following document is a third-year progress report for the period June 1, 1978 to May 31, 1979. The overall objective of the project is to study the effects of seeding techniques, species mixtures, fertilizer, ecotypes, improved plant materials, mycorrhizal fungi, and soil microorganisms on the initial and final stages of reclamation obtained through seeding and subsequent succession on disturbed oil shale lands. Plant growth medias that are being used in field-established test plots include retorted shale, soil over retorted shale, subsoil materials, and surface disturbed topsoils. Because of the long-term nature of successional and ecologically oriented studies the project is just beginning to generate significant publications. Several of the studies associated with the project have some phases being conducted principally in the laboratories and greenhouses at Colorado State Univerisity. The majority of the research, however, is being conducted on a 20 hectare Intensive Study Site located near the focal points of oil shale activity in the Piceance Basin. The site is at an elevation of 2,042 m, receives approximately 30 to 55 cm of precipitation annually, and encompasses the plant communities most typical of the Piceance Basin. Most of the information contained in this report originated from the monitoring …
Date:
March 1, 1979
Creator:
Cook, C.W.
Object Type:
Report
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.
Object Type:
Report
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.
Object Type:
Report
System:
The UNT Digital Library
Grassland/Atmosphere Response to Changing Climate: Coupling Regional and Local Scales. Final Report
The objectives of the study were: to evaluate the response of grassland ecosystems to atmospheric change at regional and site scales, and to develop multiscaled modeling systems to relate ecological and atmospheric models with different spatial and temporal resolutions. A menu-driven shell was developed to facilitate use of models at different temporal scales and to facilitate exchange information between models at different temporal scales. A detailed ecosystem model predicted that C{sub 3} temperate grasslands wig respond more strongly to elevated CO{sub 2} than temperate C{sub 4} grasslands in the short-term while a large positive N-PP response was predicted for a C{sub 4} Kenyan grassland. Long-term climate change scenarios produced either decreases or increases in Colorado plant productivity (NPP) depending on rainfall, but uniform increases in N-PP were predicted in Kenya. Elevated CO{sub 2} is likely to have little effect on ecosystem carbon storage in Colorado while it will increase carbon storage in Kenya. A synoptic climate classification processor (SCP) was developed to evaluate results of GCM climate sensitivity experiments. Roughly 80% agreement was achieved with manual classifications. Comparison of lx and 2xCO{sub 2} GCM Simulations revealed relatively small differences.
Date:
October 1, 1993
Creator:
Coughenour, M. B.; Kittel, T. G. F.; Pielke, R. A. & Eastman, J.
Object Type:
Report
System:
The UNT Digital Library
Radon Progeny Control in Buildings. Final Report
None
Date:
May 1, 1973
Creator:
Culot, M.V.J.; Olson, H.G. & Schiager, K.J.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Steady-State Thermomechanical Finite Element Analysis of Elastoviscoplastic Metal Forming Processes
Extrusion and rolling processes exhibiting large amounts of plastic flow are analyzed using a finite element technique that is based on a modified creeping viscous flow approximation. The technique, called the initial stress-rate method, iteratively corrects creeping viscous flow solutions to generate results that include elastic response. The momentum equations have been coupled with the energy equation to provide the capability to predict thermomechanical response during forming operations.
Date:
January 1, 1977
Creator:
Dawson, P.R. & Thompson, E.G.
Object Type:
Article
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.
Object Type:
Report
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
'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.
Object Type:
Report
System:
The UNT Digital Library
Investigation of the Pathway of Contaminated Soil Transported to Plant Surfaces by Raindrop Splash
The environmental transport pathway of soil-borne radioisotopes to vegetation surfaces via raindrop splash was studied. The data show that soil can significantly contribute to the contamination found on plants. Further detailed study is needed to calculate the rate constant for the raindrop splash and retention pathways. 8 references, 1 figure. (ACR)
Date:
October 21, 1983
Creator:
Dreicer, M.; Hakonson, T. E.; Whicker, F. W. & White, G. C.
Object Type:
Article
System:
The UNT Digital Library
Novel Concepts in Electrochemical Solar Cells. Third Quarterly Progress Report, November 15, 1979-January 15, 1980. [Molten Salt Electrolytes]
Efforts have been primarily directed toward evaluation of the room temperature molten salt electrolyte in terms of its overall performance for photovoltaic cells. Mass transport processes may prove to be the rate-limiting factor for such electrolytes, unless the concentration of the photo-active redox component can be increased and the solvent viscosity reduced. Acid-base surface chemistry of n-GaAs as occurs in aqueous systems, has been found present and its consequences will be further explored. The selection and optimization of PEC electrolytes is a complex task and we believe that a systems approach would facilitate in identifying the basic electrolyte properties needed. A preliminary analysis reveals that although some of the criteria for an electrolyte are definable precisely, others do require empirical experimentation. It can be concluded that relatively few electrolytes in current use are adequate and it would appear that greater efforts to develop electrolytes would be advantageous. The various types of electrolytes that could be used for PEC's have been identified. Good quality MoSe/sub 2/ single crystals can be grown and short circuit currents greater than previously reported have been achieved in an I/sub 2//I/sup -//Pt cell. A novel technique to produce photo-active films by anodization is being investigated, initially …
Date:
January 1, 1980
Creator:
DuBow, J.; Job, R. & Krishnan, R.
Object Type:
Report
System:
The UNT Digital Library
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.
Object Type:
Report
System:
The UNT Digital Library
Solar Thermal Electric Power Systems With Line-Focus Collectors. Final Report
Electric power generation by conventional Rankine cycle heat engines with heat supplied by line-focus solar collectors was investigated. The objectives of the study were: (1) determine which of four types of line-focus solar collectors coupled with turbine-generators of conventional design has the potential to produce low-cost electric power with thermal energy in 100 to 300/sup 0/C range; (2) develop performance and cost relationships for organic Rankine cycle engines for power generation capacities from 3 MW/sub e/ to 300 MW/sub e/; (3) develop conceptual storage units for organic fluid systems. Evaluation procedures and study results and conclusion are presented and discussed in detail. (WHK)
Date:
December 1, 1978
Creator:
Duff, W. S.; Karaki, S.; Shaner, W. W.; Wilbur, P. J.; Somers, E. V.; Grimble, R. E. et al.
Object Type:
Report
System:
The UNT Digital Library