76,803 Matching Results

Results open in a new window/tab.

Transposable elements and genetic instabilities in crop plants (open access)

Transposable elements and genetic instabilities in crop plants

Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.
Date: April 10, 1981
Creator: Burr, B. & Burr, F.
Object Type: Article
System: The UNT Digital Library
Renewable energy and utility regulation (open access)

Renewable energy and utility regulation

This report summarizes the results of a joint project on renewable energy of the National Association of Regulatory Utility Commissioners (NARUC) and the US DOE. NARUC'S Task Force on Renewable Energy conducted a review of the current state of renewable energy technologies to evaluate their potential and extract key policy lessons from experience already gained in deployment of these technologies in numerous states. The main focus of this effort has been to clarify how utility regulators affect the development of renewable energy resources. The goal of the project was twofold: (1) identify the factors that have led to success or failure or renewable energy technologies in various energy markets, and (2) to develop an agenda on renewable energy and utility regulation for NARUC and the DOE. This report consists of three sections: renewable energy contributions, costs and potential; factors affecting development of renewable energy resources; and a renewable energy agenda for NARUC.
Date: April 10, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Mound Laboratory tritium environmental study: 1976--1977 (open access)

Mound Laboratory tritium environmental study: 1976--1977

In the course of an extensive investigation of tritium in the aquifer underlying the Mound Facility site, an unusual behavior was noted for a beta-emitting radionuclide contaminant present in the environs of the abandoned Miami-Erie Canal adjacent to the laboratory site. The soil contaminant was determined to be tritium, of which 90% was in the form of a relatively stable or bound species that was not readily exchangeable with the free water in the soil. (Bound-to-exchangeable transfer half-time was found to be approximately 3 yr.) The contamination was found to be concentrated within two feet of the surface in the center of the canal channel and near the Facility site drainage ditch and canal confluence. In order to characterize the contaminant and to assess its potential for reaching the aquifer, an analysis program and study were initiated in September 1976. The results and findings from the first phase of this work which was completed in February 1977 are the subject of this report.
Date: April 10, 1978
Creator: Kershner, C.J. & Rhinehammer, T.B.
Object Type: Report
System: The UNT Digital Library
Fracture-mechanics analysis of a thirty-inch gas autoclave (open access)

Fracture-mechanics analysis of a thirty-inch gas autoclave

None
Date: October 10, 1975
Creator: Thompson, W. F.
Object Type: Report
System: The UNT Digital Library
Radiation damage measurements on rock salt and other minerals for waste disposal applications. Quarterly report, January 1, 1980-March 31, 1980 (open access)

Radiation damage measurements on rock salt and other minerals for waste disposal applications. Quarterly report, January 1, 1980-March 31, 1980

Different aspects of radiation damage in both synthetic NaCl crystals and various natural rock salt samples as well as granite, basalt and other minerals which will be important for radioactive waste disposal applications are being investigated. The principal means of measuring radiation damage is the determination of F-center concentrations, and the concentration and size of sodium metal colloid particles. Formation of these and other defects during irradiation and the annealing of defects and characterization of other processes occurring after irradiation are being studied as a function of dose rate, total dose, sample temperature during irradiation, strain applied prior to and during irradiation, etc. Measurements are being made on synthetic NaCl and natural rock salt samples from different geological locations, including some potential repository sites. It will be necessary to determine if radiation damage in the minerals from different localities is similar. If non-negligible differences are observed a detailed study must be made for each locality under consideration. Almost all current studies are being made on rock salt but other minerals particularly granite and basalt are being phased into the program. It is now established that radiation damage formation in both natural and synthetic rock salt is strongly dependent on strain. …
Date: April 10, 1980
Creator: Swyler, K. J.; Loman, J. M.; Teutonico, L. J.; Elgort, G. E. & Levy, P. W.
Object Type: Report
System: The UNT Digital Library
Uniform laser ablative acceleration of targets at 10/sup 14/ W/cm/sup 2/ (open access)

Uniform laser ablative acceleration of targets at 10/sup 14/ W/cm/sup 2/

We present the first detailed investigations of the ablative acceleration of planar targets while simultaneously using high irradiance (10/sup 14/ W/cm/sup 2/), large focal diameters (1 mm) and long laser pulse duration (3 nsec). Included are measurements of target preheat, ablation pressures and uniformity achieved under these conditions. Targets were accelerated to high velocities with velocity profile uniformity approaching that required for high gain pellet implosions.
Date: August 10, 1982
Creator: Obenschain, S. P.; Whitlock, R. R.; McLean, E. A.; Ripin, B. H.; Price, R. H.; Phillion, D. W. et al.
Object Type: Report
System: The UNT Digital Library
A Bench-Scale Natural-Recirculation Dissolver (open access)

A Bench-Scale Natural-Recirculation Dissolver

A natural-recirculation dissolver closely approaching a stirred-tank reactor in behavior was developed, and its feasibility was demonstrated in the mercury-catalyzed dissolution of aluminum in nitric acid, It was designed to utilize the heat of reaction and evolution of gaseous reaction products for recirculation and mixing. The dissolvent was 5-molar nitric acid, containing mercury in concentrations from 10/sup -4/ to 10/sup -3/ molar as a catalyst. Dissolution rates for 1/7 scale, simulated MTR fuel elements of 2-S aluminum ranged from 0.25 to 4.0 mg/(cm/sup 2/)(rain), depending on the catalyst concentration in the dissolvent and the dissolvent flow rate. For comparable catalyst and acid feed concentrations, dissolution rates, based on unit net superficial velocities, were nearly 25 times those for dissolution of randomly- packed flat plates in a pilot plant, continuous, flooded dissolver. (auth)
Date: January 10, 1962
Creator: Erickson, E. E.
Object Type: Report
System: The UNT Digital Library
Pressure limits of negative ion sources based upon gas efficiency and extracted ion-current density (open access)

Pressure limits of negative ion sources based upon gas efficiency and extracted ion-current density

The nature of the electrical discharge has an obvious impact upon the gas efficiency of an ion source and on the current density whch can be drawn from it. However external factors, such as the conductance of the grids and the background pressure along the beamline, also have an effect. Simple approximations based upon these factors show that there is a lower limit to the pressure of an ion source, which can deliver an ion beam of given current density at a specific gas efficiency. Estimates of ion stripping losses in a double gridded structure show that for all practical purposes, there is an upper limit as well.
Date: March 10, 1982
Creator: Fink, J.
Object Type: Report
System: The UNT Digital Library
Investigation into the repetition-rate limitations of magnetic switches (open access)

Investigation into the repetition-rate limitations of magnetic switches

The use of magnetic switches to generate high power pulses has opened up a whole new spectrum of possibilities. Here we describe an investigation into the maximum repetition rates possible with these devices.
Date: February 10, 1982
Creator: Birx, D. L.; Reginato, L. L. & Schmidt, J. A.
Object Type: Article
System: The UNT Digital Library
SLAC Divertor Channel Entrance Thermal Stress Analysis (open access)

SLAC Divertor Channel Entrance Thermal Stress Analysis

X-ray beams emerging from the new SLAC electron-positron storage ring (PEP) impinge on the entrance to tangential divertor channels causing highly localized heating in the channel structure. Analyses were completed to determine the temperatures and thermally-induced stresses due to this heating. These parts are cooled with water flowing axially over them at 30/sup 0/C. The current design and operating conditions should result in the entrance to the new divertor channel operating at a peak temperature of 123/sup 0/C with a peak thermal stress at 91% of yield. Any micro-cracks that form due to thermally-induced stresses should not propagate to the coolant wall nor form a path for the coolant to leak into the storage ring vacuum. 34 figs., 4 tabs.
Date: July 10, 1985
Creator: Johnson, Gary L.; Stein, Werner; Lu, Stephen C. & Riddle, Robert A.
Object Type: Report
System: The UNT Digital Library
Pilot demonstration: enhanced oil recovery by micellar-polymer waterflooding, Bell Creek field. Monthly technical progress report for October 1977 (open access)

Pilot demonstration: enhanced oil recovery by micellar-polymer waterflooding, Bell Creek field. Monthly technical progress report for October 1977

The work described covers the tasks for: Micellar-Polymer Systems Selection and Evaluation, Site Development, Pilot Performance Predictions, Fluid Distribution Facilities, and Log-Inject-Log Tests. (DLC)
Date: November 10, 1977
Creator: unknown
Object Type: Report
System: The UNT Digital Library
[News Clip: Spam-o-Rama] captions transcript

[News Clip: Spam-o-Rama]

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 10pm.
Date: April 10, 1994, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Aylor] captions transcript

[News Clip: Aylor]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: August 10, 1994, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Shelters] captions transcript

[News Clip: Shelters]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: February 10, 1994, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Houston murders] captions transcript

[News Clip: Houston murders]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: July 10, 1994, 5:30 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Locomotive] captions transcript

[News Clip: Locomotive]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: January 10, 1994, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Botanic PCB] captions transcript

[News Clip: Botanic PCB]

B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: June 10, 1994, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Carjacking] captions transcript

[News Clip: Carjacking]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: October 10, 1994, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: MO storms] captions transcript

[News Clip: MO storms]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: April 10, 1994, 5:30 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Aylor] captions transcript

[News Clip: Aylor]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: August 10, 1994, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Shuttle] captions transcript

[News Clip: Shuttle]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: April 10, 1994, 5:30 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: War room part 1] captions transcript

[News Clip: War room part 1]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: November 10, 1994, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
[News Clip: Murder sentence] captions transcript

[News Clip: Murder sentence]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: March 10, 1995, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Object Type: Video
System: The UNT Digital Library
Importance of high order momentum terms in SLC optics (open access)

Importance of high order momentum terms in SLC optics

The evaluation of background levels at the SLC relies, in several cases, on the proper representation of how low momentum electrons propagate through the Arcs and the Final Focus System (FFS). For example, beam - gas bremsstrahlung in the arcs causes electrons of up to 6% energy loss to be transported through to the IP; secondary showers on edges of masks and collimators yield debris with a very wide momentum spectrum. This note is a naive attempt at checking the validity of TRANSPORT and TURTLE calculations, by evaluating the contributions of the momentum terms to increasingly higher order, and checking the mutual consistency of the results produced by the two methods on a beam of wide momentum spread. 8 refs., 4 figs., 1 tab.
Date: July 10, 1985
Creator: Kozanecki, W.
Object Type: Report
System: The UNT Digital Library