Resource Type
Collection
Office of Scientific & Technical Information Technical Reports
15,024
Congressional Research Service Reports
3,774
Technical Report Archive and Image Library
2,427
National Advisory Committee for Aeronautics Collection
1,171
Government Accountability Office Reports
787
Texas State Publications
478
TRAIL Microcard Collection
443
Texas State Auditor's Office: Reports
87
Office of Technology Assessment
74
End of Term Publications
50
7 More
Serial/Series Title
NACA Research Memorandums
451
Atomic Energy Commission Reports
425
NACA Technical Notes
368
CRS Issue Briefs
207
United States Geological Survey Reports
161
NACA Technical Memorandums
124
Argonne National Laboratory Reports
112
NACA Wartime Reports
111
Trace elements investigations report
101
GJBX
95
538 More
Degree Discipline
Country
States
Decade
Month
Language
22,715 Matching Results
Results open in a new window/tab.
Results:
1 - 24 of
22,715
next
0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology
Thermophotovoltaic (TPV) diodes fabricated from 0.52eV lattice-matched InGaAsSb alloys are grown by Metal Organic Vapor Phase Epitaxy (MOVPE) on GaSb substrates. 4cm{sup 2} multi-chip diode modules with front-surface spectral filters were tested in a vacuum cavity and attained measured efficiency and power density of 19% and 0.58 W/cm{sup 2} respectively at operating at temperatures of T{sub radiator} = 950 C and T{sub diode} = 27 C. Device modeling and minority carrier lifetime measurements of double heterostructure lifetime specimens indicate that diode conversion efficiency is limited predominantly by interface recombination and photon energy loss to the GaSb substrate and back ohmic contact. Recent improvements to the diode include lattice-matched p-type AlGaAsSb passivating layers with interface recombination velocities less than 100 cm/s and new processing techniques enabling thinned substrates and back surface reflectors. Modeling predictions of these improvements to the diode architecture indicate that conversion efficiencies from 27-30% and {approx}0.85 W/cm{sup 2} could be attained under the above operating temperatures.
Date:
June 9, 2004
Creator:
Dashiell, M. W.; Beausang, J. F.; Nichols, G.; Depoy, D. M.; Danielson, L. R.; Ehsani, H. et al.
System:
The UNT Digital Library
1- and 2-D computer analysis of an HDL stress wave switch, 1974, June 25
None
Date:
June 25, 1974
Creator:
Mahler, J.
System:
The UNT Digital Library
1-MWE Heat Exchangers for OTEC Final Design Report
The design of a 1 MWe OTEC heat exchanger is documented, including the designs of the evaporator and associated systems, condenser, instrumentation, and materials for corrosion/erosion control and fabrication processes. (LEW)
Date:
June 19, 1980
Creator:
Sprouse, A.M.
System:
The UNT Digital Library
2.1 Pan-WCRP Monsoon Modelling Workshop Summary
Ken Sperber led a discussion of the outcome of the Pan-WCRP Monsoon Modelling Workshop that was held at the University of California at Irvine from 15-17 June 2005. At the workshop presentations from key CLIVAR and GEWEX panels were presented to highlight the outstanding problems in modelling the Earth's monsoons. Additionally, presentations from invited experts were given to highlight important aspects of monsoon phenomena and processes, such as low-level jets, air-sea interaction, predictability, observational networks/studies, and model test beds etc. Since all persons attending the CLIVAR AAMP meeting were present for all, or most, of the monsoon workshop, a detailed description of the workshop presentations was not given. Rather, the discussion was focused on the recommendations of the workshop breakout groups and their relevance to CLIVAR AAMP. CLIVAR AAMP endorsed the near-term workshop recommendation of investigating the diurnal cycle using a hierarchy of models a key way forward for promoting CLIVAR/GEWEX interactions. In GCM studies CLIVAR researchers have identified the diurnal cycle as a forced ''mode'' of variability that is poorly represented in terms of amplitude and phase, especially in the case of precipitation. Typical phase errors of 6-12 hours are noted over both land and ocean in GCMs. CLIVAR …
Date:
June 28, 2005
Creator:
Sperber, K R
System:
The UNT Digital Library
2, Pulse-mode expansions and refractive indices in plane-wave propagation
This memo presents basic background theory for treating simultaneous propagation of electromagnetic pulses of various colors, directed along a common ray, through a molecular vapor. The memo discusses some techniques for expanding the positive frequency part of the transverse electric field into pulse modes, characterized by carrier frequencies within a modulated envelope. We discuss, in the approximation of plane waves with slowly varying envelopes, a set of uncoupled envelope equations in which a polarization mode-envelope acts as a source for an electric-field envelope. These equations, when taken with a prescription for the polarization field, are the basic equations of plane-wave pulse propagation through a molecular medium. We discuss two ways of treating dispersive media, one based upon expansions in the frequency domain and the other based in the time domain. In both cases we find envelope equations that involve group velocities. This memo represents a portion of a more extensive treatment of propagation to be presented separately. Many of the equations presented here have been described in various books and articles. They are collected and described here as a summary and review of contemporary theory.
Date:
June 20, 1987
Creator:
Shore, B. W.; Sacks, R.; Karr, T.; Morris, J. & Paisner, J. A.
System:
The UNT Digital Library
3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface
Gian Fradelizio, a Rice Ph.D. student has completed reprocessing the 3D seismic reflection data acquired at Hill AFB through post-stack depth migration for comparison to the traveltime and waveform tomography results. Zelt, Levander, Fradelizio, and 5 others spent a week at Hill AFB in September 2005, acquiring an elastic wave data set along 2 profiles. We used 60 3-component Galperin mounted 40 Hz geophones recorded by 3 GEOMETRICS Stratavision systems. The seismic source employed was a sledgehammer used to generate transverse, and radial, and vertical point source data. Data processing has begun at Rice to generate S-wave reflection and refraction images. We also acquired surface wave and ground penetrating rada data to complement the elastic wave dataset.
Date:
June 1, 2005
Creator:
Levander, Alan R.
System:
The UNT Digital Library
3-D Spectral Induced Polarization (IP) Imaging: Non-Invasive Characterization Of Contaminant Plumes
The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth's subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are 1. 2. 3. Understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations. Developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field. Developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties.
Date:
June 1, 1997
Creator:
Morgan, Dale F.; Lesmes, David P.; Rodi, William; Shi, Weiqun; Frye, Kevin, M. & Sturrock, John
System:
The UNT Digital Library
3-D Spectral IP Imaging: Non-Invasive Characterization DE FG02 96ER 14714
The Earth Resources Laboratory (ERL) performed a broad foundational study of spectral induced polarization (SIP) for site characterization. The project encompassed laboratory studies of microgeometry and chemistry effects on Induced Polarization (IP), an investigation of electromagnetic coupling (emc) noise, and development of 3D modeling and inversion codes. The major finding of the project is that emc noise presents a critical limitation for field implementation of SIP and conventional correction methods are inadequate. The project developed a frequency domain 3D complex resistivity modeling and inversion code Laboratory experiments were conducted to study the effects of solution chemistry and microgeometry on the SIP response of sandstone. Results indicate that changes in chemistry affect the magnitude of the spectral IP response and changes in microgeometry affect the shape of the spectral IP response. The developed physiochemical IP model can be used to invert spectral IP data for an apparent grain size distribution. Laboratory studies over the last twenty years have shown that SIP data must be acquired over several decades of frequency and include frequencies greater than 1kHz. A model of the components of emc noise has been developed and investigation with this model showed that inductive coupling is the most significant component. …
Date:
June 1, 2000
Creator:
Morgan, F. Dale; Rodi, William & Lesmes, David
System:
The UNT Digital Library
3-D Spectral IP Imaging: Non-Invasive Characterization of Contaminant Plumes
The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth's subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are: (1) Understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations. (2) Developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field. (3) Developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties.
Date:
June 1, 1998
Creator:
Morgan, F. Dale; Rodi, William & Lesmes, David
System:
The UNT Digital Library
3-D Spectral IP Imaging: Non-Invasive Characterization of Contaminant Plumes. 1998 Annual Progress Report
'The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth''s subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are: (1) understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations; (2) developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field; (3) developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties. The authors laboratory experiments to date are described in Appendices A and B, which consist of two papers submitted to the annual SAGEEP conference (Frye et al., 1998; Sturrock et al., 1998). The experiments involved measurements of complex resistivity vs. frequency on a suite of brine saturated sandstone samples. In one set of experiments, the fluid chemistry (pH, ionic strength, and cation type) was varied. In a second set of experiments, the microgeometry of the rock matrix was varied. The experiments showed that spectral IP responses …
Date:
June 1, 1998
Creator:
Morgan, F. D.; Rodi, W. & Lesmes, D.
System:
The UNT Digital Library
3 GeV Booster Synchrotron Conceptual Design Report
Synchrotron light cna be produced from a relativistic particle beam circulating in a storage ring at extremely high intensity and brilliance over a large spectral region reaching from the far infrared regime to hard x-rays. The particles, either electrons or positrons, radiate as they are deflected in the fields of the storage ring bending magnets or of magnets specially optimized for the production of synchrotron light. The synchrotron light being very intense and well collimated in the forward direction has become a major tool in a large variety of research fields in physics, chemistry, material science, biology, and medicine.
Date:
June 2, 2009
Creator:
Wiedemann, Helmut
System:
The UNT Digital Library
4-D High-Resolution Seismic Reflection Monitoring of Miscible CO2 Injected into a Carbonate Reservoir
The objective of this research project was to acquire, process, and interpret multiple high-resolution 3-D compressional wave and 2-D, 2-C shear wave seismic data in the hopes of observing changes in fluid characteristics in an oil field before, during, and after the miscible carbon dioxide (CO{sub 2}) flood that began around December 1, 2003, as part of the DOE-sponsored Class Revisit Project (DOE No.DE-AC26-00BC15124). Unique and key to this imaging activity is the high-resolution nature of the seismic data, minimal deployment design, and the temporal sampling throughout the flood. The 900-m-deep test reservoir is located in central Kansas oomoldic limestones of the Lansing-Kansas City Group, deposited on a shallow marine shelf in Pennsylvanian time. After 30 months of seismic monitoring, one baseline and eight monitor surveys clearly detected changes that appear consistent with movement of CO{sub 2} as modeled with fluid simulators and observed in production data. Attribute analysis was a very useful tool in enhancing changes in seismic character present, but difficult to interpret on time amplitude slices. Lessons learned from and tools/techniques developed during this project will allow high-resolution seismic imaging to be routinely applied to many CO{sub 2} injection programs in a large percentage of shallow carbonate …
Date:
June 30, 2007
Creator:
Miller, Richard D.; Raef, Abdelmoneam E.; Byrnes, Alan P. & Harrison, William E.
System:
The UNT Digital Library
4$pi$ detector for correlation experiments
None
Date:
June 12, 1975
Creator:
Thorndike, A. M.
System:
The UNT Digital Library
5 kWe reactor power distributions
None
Date:
June 26, 1972
Creator:
Bost, D.S.
System:
The UNT Digital Library
5 MW pulsed spallation neutron source, Preconceptual design study
This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in {approx} 1 {mu}sec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor …
Date:
June 1, 1994
Creator:
unknown
System:
The UNT Digital Library
A 6.3 T Bend Magnet for the Advanced Light Source
The Advanced Light Source (ALS) is a 1.5 to 1.9 GeV high-brightness electron storage ring operating at Lawrence Berkeley Laboratory (LBL) that provides synchrotron radiation for a large variety of users. It Is proposed to replace three of the thirty six 1.5T, one meter long bend magnets with very sbort high-field superconductlng (SC) dipoles. These magnets would provide bend-magnet synchrotron radiation to six bcamlines with a critical energy of at least 6 keV that is much better suited for protein crystallography and other small-sample x-ray diffraction and adsorption studies, than is currently available at the ALS. The magnet design is described, including coil, yoke, magnetic field analysis, and cyrostat. A prototype magnet is under construction at LBL.
Date:
June 7, 1995
Creator:
Taylor, C. E. & Caspi, S.
System:
The UNT Digital Library
The 8-GeV transfer line injection into main ring
Included in this report are a brief review of the design lattice of the 8-GeV beam transfer line and the Main Ring, the recent measurements on the 8-GeV line lattice function as well as that of the Main Ring at 8-GeV. The injection matching is a very important part of the MR operation. Mismatches such as energy, timing, or position are easily corrected because they cause oscillations which are visible on the Turn-By-Turn (TBT) TV monitor display. Mis-matches due to beta and dispersion functions are detected only by using the Flying Wire or by doing measurements during beam study. A new method which makes use of the available data from TBT hardware was used to obtain the beam phase space ellipse. Data taken from Main Ring at injection gives the beta function needed for transfer matching from 8-GeV line. The result of this measurement is also presented here.
Date:
June 1, 1995
Creator:
Yang, M. J.
System:
The UNT Digital Library
9-{beta}-arabinofuranosyladenine preferentially sensitizes radioresistant squamous cell carcinoma cell lines to x-rays
The effect of 9-{beta}-arabinofuranosyladenine (ara-A) on sensitivity to the deleterious effects of x-rays was studied in six squamous cell carcinoma cell lines. Three lines were relatively radioresistant, having D{sub 0} values of 2.31 to 2.89 Gy, and the other three lines were relatively radiosensitive, having D{sub 0} values of between 1.07 and 1.45 Gy. Ara-A (50 or 500 {mu}M) was added to cultures 30 min prior to irradiation and removed 30 min after irradiation, and sensitivity was measured in terms of cell survival. The radiosensitizing effect of ara-A was very dependent on the inherent radiosensitivity of the tumor cell line. Fifty micromolar concentrations of ara-A sensitized only the two most radioresistant lines, SCC-12B.2 and JSQ-3. Five hundred micromolar concentrations of ara-A sensitized the more sensitive cell lines, SQ-20B and SQ-9G, but failed to have any effect on the radiation response of the two most sensitive cell lines, SQ-38 and SCC-61. Concentrations of ara-A as low as 10 {mu}M were equally efficient in inhibiting DNA synthesis in all six cell lines. These results suggest that the target for the radiosensitizing effect of ara-A is probably related to the factor controlling the inherent radiosensitivity of human tumor cells. Therefore, ara-A might be …
Date:
June 1, 1992
Creator:
Heaton, D.; Mustafi, R. & Schwartz, J. L.
System:
The UNT Digital Library
10-MWe pilot-plant-receiver-panel test-requirements document: Solar Thermal Test Facility
Plans are presented for insolation testing of a full-scale test receiver panel and supporting hardware which essentially duplicate both physically and functionally the design planned for the 10 MWe pilot plant. Testing includes operation during normal start and shutdown, intermittent cloud conditions, and emergencies to determine the transient and steady state operating characteristics and performance under conditions equal to or exceeding those expected in the pilot plant. The effects of variations of input and output conditions on receiver operation are also to be investigated. A brief description of the pilot plant receiver subsystem is presented, followed by a detailed description of the receiver assembly to be tested at the Solar Thermal Test Facility. Major subassemblies are described, including the receiver panel, flow control, electrical control and instrumentation, and the structural assembly. Requirements of the Solar Thermal Test Facility for the tests are given. System safety measures are described. The tests, operating conditions, and expected results are presented. Quality assurance, task responsibilities, and test documentation are also discussed. (LEW)
Date:
June 10, 1978
Creator:
unknown
System:
The UNT Digital Library
14-plex Feasibility Report
The Native Village of Unalakleet project was a feasibility study for a retrofit of a “tribally owned” three story, 14 apartment complex located in Unalakleet, Alaska. The program objective and overall goal was to create a plan for retrofitting to include current appraised value and comparable costs of new construction to determine genuine feasibility as low-income multi-family housing for tribal members.
Date:
June 21, 2013
Creator:
Kotongan, Victoria Hazel
System:
The UNT Digital Library
A 20-year data set of surface longwave fluxes in the Arctic
Creation of 20-year data set of surface infrared fluxes from satellite measurements. A reliable estimate of the surface downwelling longwave radiation flux (DLF) is a glaring void in available forcing data sets for models of Arctic sea ice and ocean circulation. We have developed a new method to estimate the DLF from a combination of satellite sounder retrievals and brightness temperatures from the TIROS Operational Vertical Sounder (TOVS), which has flown on NOAA polar-orbiting satellites continuously since late 1979. The overarching goal of this project was to generate a 20-year data set of surface downwelling longwave flux measurements from TOVS data over the Arctic Ocean. Daily gridded fields of DLF were produced with a spatial resolution of (100 km){sup 2} north of 60{sup o}N for 22.5 years rather than only 20. Surface measurements from the field station at Barrow, AK--part of the Atmospheric Radiation Measurement (ARM) Program --and from the Surface Heat Budget of the Arctic (SHEBA) were used to validate the satellite-derived fluxes and develop algorithm improvements for conditions that had resulted in systematic errors in early versions of the algorithm. The resulting data set has already been sent to two other investigators for incorporation into their research, and …
Date:
June 15, 2004
Creator:
Francis, Jennifer
System:
The UNT Digital Library
24-Channel Geophone Array for Horizontal or Vertical Boreholes Quarterly Technical Report: January-March 2003
This report describes the technical progress on a project to design and construct a multichannel geophone array that improves tomographic imaging capabilities in both surface and underground mines. Especially important in the design of the array is sensor placement. One issue related to sensor placement is addressed in this report: the method for clamping the sensor once it is emplaced in the borehole. If the sensors (geophones) are not adequately coupled to the surrounding rock mass, the resulting data will be of very poor quality. Improved imaging capabilities will produce energy, environmental, and economic benefits by increasing exploration accuracy and reducing operating costs.
Date:
June 1, 2003
Creator:
Westman, Erik C.
System:
The UNT Digital Library
A 30 MW, 200 MHz Inductive Output Tube for RF Accelerators
This program investigated development of a multiple beam inductive output tube (IOT) to produce 30 MW pulses at 200 MHz. The program was successful in demonstrating feasibility of developing the source to achieve the desired power in microsecond pulses with 70% efficiency. The predicted gain of the device is 24 dB. Consequently, a 200 kW driver would be required for the RF input. Estimated cost of this driver is approximately $1.25 M. Given the estimated development cost of the IOT of approximately $750K and the requirements for a test set that would significantly increase the cost, it was determined that development could not be achieved within the funding constraints of a Phase II program.
Date:
June 19, 2008
Creator:
Ives, R. Lawrence & Read, Michael
System:
The UNT Digital Library
45-day safety screen results and final report for tank 241-C-202, auger samples 95-Aug-026 and 95-Aug-027
Two auger samples from tank 241-C-202 (C-202) were received at the 222-S Laboratories and underwent safety screening analysis, consisting of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and total alpha activity. Two samples were submitted for energetics determination by DSC. Within the triplicate analyses of each sample, one of the results for energetics exceeded the notification limit. The sample and duplicate analyses for both augers exceeded the notification limit for TGA. As required by the Tank Characterization Plan, the appropriate notifications were made within 24 hours of official confirmation that the limits were violated.
Date:
June 19, 1995
Creator:
Baldwin, J.H.
System:
The UNT Digital Library