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Microstructural damage produced by helium in aged /sup 238/PuO/sub 2/ fuels

Description: Microstructural damage is produced in aged /sup 238/PuO/sub 2/ fuels used to power radioisotopic heat sources by the generation and release of the helium arising from alpha decay of the fuel. We obtained information about the nature and extent of this damage from metallographic examination of fuel pellets ranging in density from 87 to 94% with a grain size range of 6 to 30 ..mu..m that either were stored at ambient temperature for 18 months and then heated at 900, 1150, or 1360/sup 0/C or were stored at 900, 1150, or 1350/sup 0/C for 27 months. Microstructural damage was not observed in the fuel pellets stored at ambient temperature and then heated at 900/sup 0/C, but grain boundary bubble damage was observed in the pellets stored at ambient temperature and then heated at either 1150 or 1350/sup 0/C. More extensive damage occurred in those pellets heated at 1350/sup 0/C. Four of the higher density pellets (92 and 94% dense) stored at 900/sup 0/C shattered during storage and the rest appeared to be highly strained. The pellets stored at 1150/sup 0/C were damaged only slightly but were somewhat strained and appeared to have released their helium inventory only partially. All pellets stored at 1350/sup 0/C showed swelling and extensive void agglomeration. These data suggest that the best fuel operating temperature, as far as helium damage is concerned, would be approx. 1200/sup 0/C because below this temperature the fuel becomes highly strained and above this temperature the fuel swells ad becomes somewhat friable. Both these situations could adversely affect the impact behavior of the fuel from the standpoint of strength and fines generation.
Date: January 1, 1980
Creator: Land, C.C.
Partner: UNT Libraries Government Documents Department

The Marysville, Montana, Geothermal Project: Environmental Analysis of the Deep Geothermal Research Well

Description: The objective of this research project is to investigate a geothermal anomaly of high heat flow discovered in 1969 in central Montana, and to determine how this natural resource might be developed as a source of useful energy. Under Phase I, the natural resource will be explored, drilled, and modeled at an estimated cost of $2,588,935 over a 3-year period. Phase II, depending upon the nature of the heat source, will be developing the resource under a cooperative effort of government and private industry. This environmental analysis is intended to cover the drilling and logging operations noted under Phase I, the only work being undertaken at this time. As can be seen from Figure 1, further tests may be run at this site in later phases of the study. But since the nature of these tests are highly dependent on the results of Phase I, it is not considered productive to speculate on their environmental impact. As is show, however, any later experiments would cover a range of underground experiments, some of which consume water and others which would produce water. Before a meaningful analysis of such work can be written, it will be necessary to analyze the results of Phase I findings.
Date: February 15, 1973
Partner: UNT Libraries Government Documents Department

California Desert Conservation Area Plan: Amendment / Final Environmental Impact Statement for Ivanpah Solar Electric Generation System

Description: Report for the proposed California Desert Conservation Area Plan Amendment and Final Environmental Impact Statement for the Ivanpah Solar Electric Generating System (ISEGS) project. The proposed plan amendment adds the Ivanpah Solar Electric Generating System project site to those identified in the current California Desert Conservation Area Plan, as amended, for solar energy production.
Date: July 2010
Creator: United States. Bureau of Land Management.
Partner: UNT Libraries Government Documents Department

Final Environmental Impact Statement and Proposed Amendment to the California Desert Conservation Area Plan for the Calico Solar (formerly SES Solar One) Project

Description: This Final Environmental Impact Statement (FEIS) addresses the possible Bureau of Land Management (BLM) approval of an amendment to the California Desert Conservation Area (CDCA) Plan to allow solar energy development on a proposed project site, up to 8,230 acres in size, 37 miles east of Barstow, California.
Date: August 2010
Creator: United States. Bureau of Land Management.
Partner: UNT Libraries Government Documents Department

Proposed Revisions to Grazing Regulations for the Public Lands

Description: This final environmental impact statement (EIS) is a national-level, programmatic EIS that documents the ecological, cultural, social, and economic effects that would result from implementing the proposed regulator changes caused by the Bureau of Land Management amending the grazing regulation for the public lands, 43 CFR Part 4100, Grazing Administration - Exclusive of Alaska.
Date: October 2004
Creator: United States. Bureau of Land Management.
Partner: UNT Libraries Government Documents Department

Land grant to Levi Shumway : Monroe, Mich., 1835 October 6.

Description: Land Grant for 40 acres in Monroe, Michigan, granting "the north east quarter of the south west quarter, of section nine, in the township eight south, of range three east, in the District of lands subject to sale at Monroe, Michigan Territory, containing forty acres." This is Certificate 149.
Date: January 6, 1835
Creator: United States. General Land Office.
Partner: UNT Libraries Rare Book and Texana Collections

Solid Minerals Reclamation Handbook

Description: A document by the Bureau of Land Management that details the organization's long-term goals to shape, stabilize, and treat disturbed areas so as to make productive use of the land.
Date: unknown
Creator: United States. Department of the Interior Bureau of Land Management.
Partner: UNT Libraries Government Documents Department

Effect of powered propellers on the aerodynamic characteristics and the porpoising stability of a dynamic model of a long-range flying boat

Description: Report discusses the results of two tests: "1) aerodynamic tests to determine the effect of the slipstream and thrust from the powered propellers on the lift and trimming-moment characteristics, and 2) hydrodynamic tests to determine the effect of the powered propellers on the range of stable locations of the center of gravity (from Introduction)." Large differences in the stable range between half-thrust and full-thrust conditions were observed. Three effects of power were also involved in the location of the stable range of the center of gravity.
Date: May 1943
Creator: Land, Norman S.
Partner: UNT Libraries Government Documents Department

Oral History Interview with Werner A. Land, May 18, 1974

Description: Interview with Navy veteran Werner A. Land. The interview includes Land's personal experiences while aboard the battleship USS Maryland during the Japanese attack at Pearl Harbor on December 7, 1941.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: May 18, 1974
Creator: Marcello, Ronald E. & Land, Werner A.
Partner: UNT Oral History Program

[Land Grant, May 17, 1883]

Description: This is a land grant from the State of Texas to Levi Perryman. It has been signed by governor John Ireland, and W.C Walsh, commissioner of the general land office. The land is 90 2/5 acres, and is about 10 miles from the city of Montague.
Date: May 17, 1883
Creator: Texas. General Land Office.
Partner: UNT Libraries Special Collections

Ion-implanted PLZT ceramics: a new high-sensitivity image storage medium

Description: Results were presented of our studies of photoferroelectric (PFE) image storage in H- and He-ion implanted PLZT (lead lanthanum zirconate titanate) ceramics which demonstrate that the photosensitivity of PLZT can be significantly increased by ion implantation in the ceramic surface to be exposed to image light. More recently, implantations of Ar and Ar + Ne into the PLZT surface have produced much greater photosensitivity enhancement. For example, the photosensitivity after implantation with 1.5 x 10/sup 14/ 350 keV Ar/cm/sup 2/ + 1 x 10/sup 15/ 500 keV Ne/cm/sup 2/ is increased by about four orders of magnitude over that of unimplanted PLZT. Measurements indicate that the photosensitivity enhancement in ion-implanted PLZT is controlled by implantation-produced disorder which results in marked decreases in dielectric constant and dark conductivity and changes in photoconductivity of the implanted layer. The effects of Ar- and Ar + Ne-implantation are presented along with a phenomenological model which describes the enhancement in photosensitivity obtained by ion implantation. This model takes into account both light- and implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage V/sub c/ as a function of near-uv light intensity for both unimplanted and implanted PLZT. The model, used in conjunction with calculations of the profiles of implantation-produced disorder, has provided the information needed for co-implanting ions of different masses, e.g., Ar and Ne, to improve photosensitivity.
Date: January 1, 1980
Creator: Peercy, P.S. & Land, C.E.
Partner: UNT Libraries Government Documents Department

Environmental safety analysis tests on the Light Weight Radioisotope Heater Unit (LWRHU)

Description: A series of safety tests has been performed on the Light Weight Radioisotope Heater Unit (LWRHU), a /sup 238/PuO/sub 2/-fueled device designed to provide thermal energy at selected locations in a spacecraft. The tests simulate the thermal and mechanical environments postulated for spacecraft accidents on the launch pad and on reentry abort. The tests demonstrate almost complete containment of the fuel, or fuel simulant (depleted UO/sub 2/), in (1) an overpressure environment of 12.76 MPa (1850 psi), (2) on impact by an 18-g aluminum fuel-tank fragment at velocities greater than 750 m/s (2460 ft/s) but less than 900 m/s (2950 ft/s), (3) during a 10.5-min burn of a 0.9 x 0.9 x 0.9 m (3 x 3 x 3 ft) block of solid rocket motor propellant, (4) after impact at 49 m/s (161 ft/s) in four different orientations on a hard surface, and (5) during immersion in seawater for 1.75 years at both sea level pressure and at a pressure equivalent to 6000 m (19,700 ft) of ocean depth.
Date: May 1, 1985
Creator: Tate, R.E. & Land, C.C.
Partner: UNT Libraries Government Documents Department

Optical image storage in ion implanted PLZT ceramics

Description: Optical images can be stored in transparent lead-lanthanum-zirconate-titanate (PLZT) ceramics by exposure to near-uv light with photon energies greater than the band gas energy of approx. 3.35 eV. The image storage process relies on optically induced changes in the switching properties of ferroelectric domains (photoferroelectric effect). Stored images are nonvolatile but can be erased by uniform uv illumination and simultaneous application of an electric field. Although high quality images, with contrast variations of greater than or equal to 100:1 and spatial resolution of approx. 10 ..mu..m, can be stored using the photoferroelectric effect, relatively high exposure energies (approx. 100 mJ/cm/sup 2/) are required to store these images. This large exposure energy severely limits the range of possible applications of nonvolatile image storage in PLZT ceramics. It was found in H, He, and Ar implanted PLZT that the photosensitivity can be significantly increased by ion implantation into the surface to be exposed. The photosensitivity after implantation with 5 x 10/sup 14/ 500 keV Ar/cm/sup 2/ is increased by about three orders of magnitude over that of unimplanted PLZT. The image storage process and the effect of ion implantation is presented along with a phenomenological model which describes the enhancement in photosensitivity obtained by ion implantation. This model takes into account both light- and ion implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage with light intensity for ion implanted PLZT.
Date: January 1, 1980
Creator: Peercy, P. S. & Land, C. E.
Partner: UNT Libraries Government Documents Department

The effect of afterbody length of the hydrodynamic stability of a dynamic model of a flying boat: Langley tank model 134

Description: Report presenting some model tests that will be used to guide the relation of length of afterbody and depth of step. Results indicated that an increase in length of afterbody requires an accompanying increase in depth of step to maintain adequate landing stability.
Date: October 1945
Creator: Land, Norman S.
Partner: UNT Libraries Government Documents Department

Milford Wind Corridor Project Millard and Beaver Counties, Utah

Description: A report which analyses the environmental consequences of the Milford Wind Corridor Project. The information inside the paper assists the Bureau of Land Management in evaluating whether to grant a right-of-way (ROW) on public lands.
Date: October 15, 2008
Creator: United States. Department of the Interior Bureau of Land Management.
Partner: UNT Libraries Government Documents Department