89,898 Matching Results

Results open in a new window/tab.

Photogenerated carrier-induced reactions on uhv semiconductor surfaces (open access)

Photogenerated carrier-induced reactions on uhv semiconductor surfaces

The objective for this experimental work was to examine the reaction mechanisms, half-collision dynamics, and other optically induced chemical effects, that are operable on a well characterized single-crystal semiconductor surface. Of particular interest were reactions induced by charge transfer from the semiconductor surface including hot carrier and thermalized carrier processes. The primary technique to measure the desorbed fragment translational energies was time-of-flight mass-spectroscopy, used in conjunction with a pulsed tunable laser source. The work was carried out in ultrahigh vacuum, thus other surface spectroscopies such as temperature-programmed desorption, (TPD), (LEED), etc. were used as needed. In the project, the photoreactions of several halogen-containing molecules on GaAs(110) surfaces have been investigated. The studies have made the first observations of several new photochemical processes on uhv prepared surfaces including intermolecular charge transfer; desorption by thermal-carrier-induced reactions (including the measurement of coverage-dependent changes in the translational energies of the desorbed products); interferometric oscillation of photoinduced reactions; and self-quenching of thermal carrier reactions on surfaces.
Date: May 28, 1992
Creator: Osgood, R.M. Jr.
Object Type: Report
System: The UNT Digital Library
Nuclear Parameter Survey of Molybdenum-Uranium Alloy Fuels for the Sheldon Reactor (open access)

Nuclear Parameter Survey of Molybdenum-Uranium Alloy Fuels for the Sheldon Reactor

A parameter survey was conducted on 19-rod fuel clusters using 3 and 10 wt.% Mo--U alloys. Graphs are included for the core diameter and initial conversion ratio for k/sub eff/= 1.064 as a function of moderator can size, and for the effect of the Mo resonance integral. (D. L.C.)
Date: March 28, 1958
Creator: Blaine, R. A.
Object Type: Report
System: The UNT Digital Library
Study to optimize Cr-Mo steels to resist hydrogen and temper embrittlement. Quarterly report No. 6, November 15, 1979-February 15, 1980 (open access)

Study to optimize Cr-Mo steels to resist hydrogen and temper embrittlement. Quarterly report No. 6, November 15, 1979-February 15, 1980

A modified test technique has been developed in this program to overcome difficulties in assessing the hydrogen embrittlement susceptibility of low strength 2 1/4 Cr-1 Mo steels. One steel sample was tempered to a range of strength levels and evaluated using the new technique. The results, showing a lower strength level for which hydrogen embrittlement susceptibility can be assessed in a 446 KPa H/sub 2/S environment, are presented in this report. A review of the restructuring of the program is also given.
Date: July 28, 1980
Creator: Shaw, B.J.
Object Type: Report
System: The UNT Digital Library
NON-DESTRUCTIVE ANALYSIS OF URANIUM IN GRAPHITE FUEL ELEMENTS BY NEUTRON ACTIVATION (open access)

NON-DESTRUCTIVE ANALYSIS OF URANIUM IN GRAPHITE FUEL ELEMENTS BY NEUTRON ACTIVATION

A method is presented for the determination of uranium (as U/sup 238/) in uraniuni-loaded graphite fuel elenients by a non-destructive, direct radioactivity analysis technique. A 200-cbannel pulse-height analyzer, equipped with a 3 in. x 3 in. NaI(Tl) crystal, is used to measure the Np/sup 239/ radioactivity of the neutron-irradiated samples. The amount of U/sup 238/ in the test samples is deterimined quantitatively by comparing the Np/sup 239/ radioactivity induced in each sample with the Np/sup 239/ radioactivity induced into known standards of U/sup 238/ processed under the same conditions as the test samples. The limit of detection for U/sup 238/in samples of normal uranium composition for this method is about 1.0 x l0-4 ug. (auth)
Date: November 28, 1961
Creator: Bate, L.C.; Hampton, W.J. & Leddicotte, G.W.
Object Type: Report
System: The UNT Digital Library
Area recommendation report for the crystalline repository project: An evaluation. [Crystalline Repository Project] (open access)

Area recommendation report for the crystalline repository project: An evaluation. [Crystalline Repository Project]

An evaluation is given of DOE's recommendation of the Elk River complex in North Carolina for siting the second repository. Twelve recommendations are made including a strong suggestion that the Cherokee Tribe appeal both through political and legal avenues for inclusion as an affected area primarily due to projected impacts upon economy and public health as a consequence of the potential for reduced tourism.
Date: March 28, 1986
Creator: Beck, J E; Lowe, H & Yurkovich, S P
Object Type: Report
System: The UNT Digital Library
Investigation of sodium carbonate, sodium bicarbonate and water systems for saturated solar ponds. Final report (open access)

Investigation of sodium carbonate, sodium bicarbonate and water systems for saturated solar ponds. Final report

The overall objective of this study was to gather relevant data primarily from the published literature to investigate the technical feasibility of using a Na/sub 2/CO/sub 3/-NaHCO/sub 3/ mixture for a saturated solar pond. This objective was accomplished by a literature search and review of existing chemical information and by performing simple chemistry experiments in the laboratory. Information on density, solubility, phase diagram, equilibrium compositions, reaction rate constant, equilibrium constant, diffusion coefficient, vapor pressure and potentially useful additives is compiled. It is concluded that even though both the saturation density and solubility increase with temperature for trona, it is not chemically stable either at room temperature or higher temperatures (80/sup 0/C). Therefore, as is, trona is not suitable for use in a saturated solar pond. From the literature it has been found that sugar and gum can retard the decomposition of bicarbonate to carbonate in the mixture. Nevertheless, trona is a very attractive solute for an unsaturated solar pond. A laboratory unsaturated pond with a stable density gradient has worked without any problems for about two months at InterTechnology/Solar Corporation.
Date: March 28, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Adult Fishway Inspections on the Columbia and Snake Rivers, 1984-1985 Annual Report. (open access)

Adult Fishway Inspections on the Columbia and Snake Rivers, 1984-1985 Annual Report.

Mainstream projects which have adult fish passage facilities are inspected by project operators, fishway attendants, and state and federal fishery agencies. The overall movement of upstream migrants in 1984 appeared to be satisfactory with few delays. Special efforts were made by fishery agencies and Corps personnel to check on potential problems which appeared to exist at The Dalles and John Day Dams this year. However, adult passage facilities were operating ''in criteria'' and fish may have been delayed by temperature or other factors. Inspections were generally made once a month. Some projects were operating at less than full criteria as seen during inspections by fishery agencies this year. It appears that during periods of low tailwater, certain projects have difficulty maintaining proper head at main fishway entrances. Some main entrance gates bottom-out and water depth over these weirs are not up to desired criteria. Also it was noted that auxiliary water pumps were not being run at a rate to achieve the desired amount of water for attracting fish to the fish ladders and maintaining proper head at main fishway entrances.
Date: June 28, 1985
Creator: Basham, Larry R.
Object Type: Report
System: The UNT Digital Library
Thermal effects and mirror surface figure requirements for a diagnostic beamline at the Advanced Light Source (open access)

Thermal effects and mirror surface figure requirements for a diagnostic beamline at the Advanced Light Source

An imaging beamline based on a Kirkpatrick-Baez mirror configuration has been designed to image the electron beam in the ALS storage ring, to measure its size and shape. The electron beam emittance will be small ({epsilon}h = 3.4 {times} 10{sup {minus}9} m rad) and the quality of the image is extremely sensitive to surface figure distortion of the mirrors. Thermal distortions and surface temperatures have been calculated for radiatively cooled mirrors of various materials in a search for a simple design which avoids water cooling. The choice of mirror material and the thermal and mechanical design is discussed. 6 refs.
Date: October 28, 1991
Creator: Warwick, T. (Lawrence Berkeley Lab., CA (United States)) & Sharma, S. (Brookhaven National Lab., Upton, NY (United States))
Object Type: Article
System: The UNT Digital Library
Oil-shale-retorting and combustion system. [DOE patent application] (open access)

Oil-shale-retorting and combustion system. [DOE patent application]

The present invention is directed to the extraction of energy values from oil shale containing considerable concentrations of calcium carbonate in an efficient manner. The volatiles are separated from the oil shale in a retorting zone of a fluidized bed where the temperature and the concentration of oxygen are maintained at sufficiently low levels so that the volatiles are extracted from the oil shale with minimal combustion of the volatiles and with minimal calcination of the calcium carbonate. These gaseous volatiles and the calcium carbonate flow from the retorting zone into a freeboard combustion zone where the volatiles are burned in the presence of excess air. In this zone the calcination of the calcium carbonate occurs but at the expense of less Btu's than would be required by the calcination reaction in the event both the retorting and combustion steps took place simultaneously. The heat values in the products of combustion are satisfactorily recovered in a suitable heat exchange system.
Date: August 28, 1981
Creator: Pitrolo, Augustine A.; Mei, Joseph S. & Shang, Jerry Y.
Object Type: Patent
System: The UNT Digital Library
Nuclear reactor control apparatus (open access)

Nuclear reactor control apparatus

Nuclear reactor core safety rod release apparatus comprises a control rod having a detent notch in the form of an annular peripheral recess at its upper end, a control rod support tube for raising and lowering the control rod under normal conditions, latches pivotally mounted on the control support tube with free ends thereof normally disposed in the recess in the control rod, and cam means for pivoting the latches out of the recess in the control rod when a scram condition occurs. One embodiment of the invention comprises an additonal magnetically-operated latch for releasing the control rod under two different conditions, one involving seismic shock.
Date: August 28, 1981
Creator: Sridhar, B.N.
Object Type: Patent
System: The UNT Digital Library
Guthrie Daily News. (Guthrie, Okla. Terr.), Vol. 5, No. 1470, Ed. 1 Saturday, April 28, 1894 (open access)

Guthrie Daily News. (Guthrie, Okla. Terr.), Vol. 5, No. 1470, Ed. 1 Saturday, April 28, 1894

Daily newspaper from Guthrie, Oklahoma Territory that includes local, territorial, and national news along with advertising.
Date: April 28, 1894
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
Guthrie Daily News. (Guthrie, Okla. Terr.), Vol. 5, No. 1571, Ed. 1 Tuesday, August 28, 1894 (open access)

Guthrie Daily News. (Guthrie, Okla. Terr.), Vol. 5, No. 1571, Ed. 1 Tuesday, August 28, 1894

Daily newspaper from Guthrie, Oklahoma Territory that includes local, territorial, and national news along with advertising.
Date: August 28, 1894
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Oklahoma Democrat (Altus, Okla.), Vol. 6, No. 25, Ed. 1 Thursday, August 28, 1913 (open access)

The Oklahoma Democrat (Altus, Okla.), Vol. 6, No. 25, Ed. 1 Thursday, August 28, 1913

Weekly newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 28, 1913
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Oklahoma Leader (Guthrie, Okla.), Vol. 28, No. 10, Ed. 1 Thursday, February 28, 1918 (open access)

The Oklahoma Leader (Guthrie, Okla.), Vol. 28, No. 10, Ed. 1 Thursday, February 28, 1918

Weekly newspaper from Guthrie, Oklahoma that includes local, state, and national news along with advertising.
Date: February 28, 1918
Creator: Niblack, Leslie G.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Logan County News (Crescent, Okla.), Vol. 14, Ed. 1 Thursday, December 28, 1916 (open access)

The Logan County News (Crescent, Okla.), Vol. 14, Ed. 1 Thursday, December 28, 1916

Weekly newspaper from Crescent, Oklahoma that includes local, state, and national news along with advertising.
Date: December 28, 1916
Creator: Jent, H. C.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Mangum Star. (Mangum, Okla.), Vol. 13, No. 34, Ed. 1 Thursday, February 28, 1901 (open access)

The Mangum Star. (Mangum, Okla.), Vol. 13, No. 34, Ed. 1 Thursday, February 28, 1901

Weekly newspaper from Mangum, Oklahoma that includes local, territorial, and national news along with advertising.
Date: February 28, 1901
Creator: Townsend, G. B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Greer County Democrat (Mangum, Okla.), Vol. 26, No. 7, Ed. 1 Thursday, October 28, 1915 (open access)

The Greer County Democrat (Mangum, Okla.), Vol. 26, No. 7, Ed. 1 Thursday, October 28, 1915

Weekly newspaper from Mangum, Oklahoma that includes local, state, and national news along with advertising.
Date: October 28, 1915
Creator: Watt, W. O.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Mangum Star. (Mangum, Okla.), Vol. 21, No. 31, Ed. 1 Thursday, January 28, 1909 (open access)

The Mangum Star. (Mangum, Okla.), Vol. 21, No. 31, Ed. 1 Thursday, January 28, 1909

Weekly newspaper from Mangum, Oklahoma that includes local, state, and national news along with advertising.
Date: January 28, 1909
Creator: Taylor, J. E.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Mangum Star. (Mangum, Okla.), Vol. 12, No. 35, Ed. 1 Wednesday, February 28, 1900 (open access)

The Mangum Star. (Mangum, Okla.), Vol. 12, No. 35, Ed. 1 Wednesday, February 28, 1900

Weekly newspaper from Mangum, Oklahoma that includes local, territorial, and national news along with advertising.
Date: February 28, 1900
Creator: Scarborough, James
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Mangum Star. (Mangum, Okla. Terr.), Vol. 18, No. 26, Ed. 1 Thursday, December 28, 1905 (open access)

The Mangum Star. (Mangum, Okla. Terr.), Vol. 18, No. 26, Ed. 1 Thursday, December 28, 1905

Weekly newspaper from Mangum, Oklahoma that includes local, territorial, and national news along with advertising.
Date: December 28, 1905
Creator: Echols, R. C.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Oklahoma Democrat (Altus, Okla.), Vol. 5, No. 38, Ed. 1 Thursday, November 28, 1912 (open access)

The Oklahoma Democrat (Altus, Okla.), Vol. 5, No. 38, Ed. 1 Thursday, November 28, 1912

Weekly newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: November 28, 1912
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Mangum Mirror (Mangum, Okla.), Vol. 1, No. 47, Ed. 1 Tuesday, August 28, 1917 (open access)

The Mangum Mirror (Mangum, Okla.), Vol. 1, No. 47, Ed. 1 Tuesday, August 28, 1917

Semi-weekly newspaper from Mangum, Oklahoma that includes local, state, and national news along with advertising.
Date: August 28, 1917
Creator: Ryder, J. W.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Guthrie Daily News. (Guthrie, Okla. Terr.), Vol. 5, No. 1422, Ed. 1 Wednesday, February 28, 1894 (open access)

Guthrie Daily News. (Guthrie, Okla. Terr.), Vol. 5, No. 1422, Ed. 1 Wednesday, February 28, 1894

Daily newspaper from Guthrie, Oklahoma Territory that includes local, territorial, and national news along with advertising.
Date: February 28, 1894
Creator: unknown
Object Type: Newspaper
System: The Gateway to Oklahoma History
Oklahoma State Register (Guthrie, Okla.), Vol. 27, No. 9, Ed. 1 Thursday, June 28, 1917 (open access)

Oklahoma State Register (Guthrie, Okla.), Vol. 27, No. 9, Ed. 1 Thursday, June 28, 1917

Weekly newspaper from Guthrie, Oklahoma that includes local, state, and national news along with advertising.
Date: June 28, 1917
Creator: Golobie, John
Object Type: Newspaper
System: The Gateway to Oklahoma History