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A 1-Joule laser for a 16-fiber injection system

Description: A 1-J laser was designed to launch light down 16, multi-mode fibers (400-{micro}m-core dia.). A diffractive-optic splitter was designed in collaboration with Digital Optics Corporation (DOC), and was delivered by DOC. Using this splitter, the energy injected into each fiber varied <1%. The spatial profile out of each fiber was such that there were no ''hot spots,'' a flyer could successfully be launched and a PETN pellet could be initiated. Preliminary designs of the system were driven by system efficiency where a pristine TEM{sub 00} laser beam would be required. The laser is a master oscillator, power amplifier (MOPA) consisting of a 4-mm-dia. Nd:YLF rod in the stable, q-switched oscillator and a 9.5-mm-dia. Nd:YLF rod in the double-passed amplifier. Using a TEM{sub 00} oscillator beam resulted in excellent transmission efficiencies through the fibers at lower energies but proved to be quite unreliable at higher energies, causing premature fiber damage, flyer plate rupture, stimulated Raman scattering (SRS), and stimulated Brillouin scattering (SBS). Upon further investigation, it was found that both temporal and spatial beam formatting of the laser were required to successfully initiate the PETN. Results from the single-mode experiments, including fiber damage, SRS and SBS losses, will be presented. In addition, results showing the improvement that can be obtained by proper laser beam formatting will also be presented.
Date: April 6, 2004
Creator: Honig, J
Partner: UNT Libraries Government Documents Department

A-01 metals in stormwater runoff evaluation

Description: As a part of the A-01 investigation required by the NPDES permit, an investigation was performed to ascertain the concentrations of metals specifically copper (Cu), lead (Pb), and zinc (Zn) in stormwater being discharged through the outfall. This information would indicate whether all water being discharged would have to be treated or if only a portion of the discharged stormwater would have to be treated. A study was designed to accomplish this. The first goal was to determine if the metal concentrations increased, decreased, or remained the same as flow increased during a rain event. The second goal was to determine if the concentrations in the storm water were due to dissolved. The third goal was to obtain background data to ascertain if effluent credits could be gained due to naturally occurring metals.Samples from this study were analyzed and indicate that the copper and lead values increase as the flow increases while the zinc values remain essentially the same regardless of the flow rate. Analyses of samples for total metals, dissolved metals, TSS, and metals in solids was complicated because in all cases metals contamination was found in the filters themselves. Some conclusions can be derived if this problem is taken into account when analyzing the data. Copper concentrations in the total and dissolved fractions as well as the TSS concentrations followed the hydrograph at this outfall but the copper in solids concentration appeared to peak in the first flush and decline to nondetectable rapidly over the course of the storm event. Lead was present in the total analysis but not present in the dissolved fraction or the solids fraction of the samples. The data for zinc was interesting in that the dissolved fractions were higher than the total fraction in three out of four samples. This is probably due ...
Date: November 6, 1997
Creator: Eldridge, L. L.
Partner: UNT Libraries Government Documents Department

2-D or not 2-D, that is the question: A Northern California test

Description: Reliable estimates of the seismic source spectrum are necessary for accurate magnitude, yield, and energy estimation. In particular, how seismic radiated energy scales with increasing earthquake size has been the focus of recent debate within the community and has direct implications on earthquake source physics studies as well as hazard mitigation. The 1-D coda methodology of Mayeda et al. has provided the lowest variance estimate of the source spectrum when compared against traditional approaches that use direct S-waves, thus making it ideal for networks that have sparse station distribution. The 1-D coda methodology has been mostly confined to regions of approximately uniform complexity. For larger, more geophysically complicated regions, 2-D path corrections may be required. The complicated tectonics of the northern California region coupled with high quality broadband seismic data provides for an ideal ''apples-to-apples'' test of 1-D and 2-D path assumptions on direct waves and their coda. Using the same station and event distribution, we compared 1-D and 2-D path corrections and observed the following results: (1) 1-D coda results reduced the amplitude variance relative to direct S-waves by roughly a factor of 8 (800%); (2) Applying a 2-D correction to the coda resulted in up to 40% variance reduction from the 1-D coda results; (3) 2-D direct S-wave results, though better than 1-D direct waves, were significantly worse than the 1-D coda. We found that coda-based moment-rate source spectra derived from the 2-D approach were essentially identical to those from the 1-D approach for frequencies less than {approx}0.7-Hz, however for the high frequencies (0.7{le} f {le} 8.0-Hz), the 2-D approach resulted in inter-station scatter that was generally 10-30% smaller. For complex regions where data are plentiful, a 2-D approach can significantly improve upon the simple 1-D assumption. In regions where only 1-D coda correction is available it is ...
Date: June 6, 2005
Creator: Mayeda, K; Malagnini, L; Phillips, W S; Walter, W R & Dreger, D
Partner: UNT Libraries Government Documents Department

3-D THERMAL EVALUATIONS FOR a FUELED EXPERIMENT in the ADVANCED TEST REACTOR

Description: The DOE Advanced Fuel Cycle Initiative and Generation IV reactor programs are developing new fuel types for use in the current Light Water Reactors and future advanced reactor concepts. The Advanced Gas Reactor program is planning to test fuel to be used in the Next Generation Nuclear Plant (NGNP) nuclear reactor. Preliminary information for assessing performance of the fuel will be obtained from irradiations performed in the Advanced Test Reactor large ''B'' experimental facility. A test configuration has been identified for demonstrating fuel types typical of gas cooled reactors or fast reactors that may play a role in closing the fuel cycle or increasing efficiency via high temperature operation Plans are to have 6 capsules, each containing 12 compacts, for the test configuration. Each capsule will have its own temperature control system. Passing a helium-neon gas through the void regions between the fuel compacts and the graphite carrier and between the graphite carrier and the capsule wall will control temperature. This design with three compacts per axial level was evaluated for thermal performance to ascertain the temperature distributions in the capsule and test specimens with heating rates that encompass the range of initial heat generation rates.
Date: October 6, 2004
Creator: Ambrosek, R. G.; Chang, G. S. & Utterbeck, D. J.
Partner: UNT Libraries Government Documents Department

The 9/11 Commission and a National Counterterrorism Center: Issues and Options for Congress

Description: From Summary: "This report, which will be updated, examines a number of issues as Congress considers codification of an NCTC. One issue is whether the centralization remedy the commission has recommended fits the problems associated specifically with the 9/11 intelligence failure, and perhaps more broadly, the systematic maladies affecting the Intelligence Community. There are at least four options for congressional consideration: (1) NCTC with intelligence and operational planning duties, (2) NCTC restricted to an intelligence role, (3) NCTC restricted to an operational planning role, and (4) status quo plus-viewing the newly forming collected entity as a pilot potential NCTC. As one of its 41 recommendations, the 9/11 Commission recommended the creation of a National Counterterroism Center (NCTC)."
Date: October 6, 2004
Creator: Masse, Todd
Partner: UNT Libraries Government Documents Department

9/11 Commission: Current Legislative Proposals for U.S. Immigration Law and Policy

Description: This report briefly discusses some of the major immigration areas under consideration in comprehensive reform proposals suggested by the 9/11 Commission, including asylum, biometric tracking systems, border security, document security, exclusion, immigration enforcement, and visa issuances. It refers to other CRS reports that discuss these issues in depth and will be updated as needed.
Date: December 6, 2004
Creator: Garcia, Michael John & Wasem, Ruth Ellen
Partner: UNT Libraries Government Documents Department

20% Partial Siberian Snake in the AGS.

Description: An 11.4% partial Siberian snake was used to successfully accelerate polarized proton through a strong intrinsic depolarizing spin resonance in the AGS. No noticeable depolarization was observed. This opens up the possibility of using a 20% to 30% partial Siberian snake in the AGS to overcome all weak and strong depolarizing spin resonances. Some design and operation issues of the new partial Siberian snake are discussed.
Date: November 6, 2002
Creator: Huang, H; Bai, M; Brown, K A; Glenn, W; Luccio, A U; Mackay, W W et al.
Partner: UNT Libraries Government Documents Department

100 Areas technical activities report -- Physics, November 1951

Description: Activities discussed in this report are as follows: shielding studies; xenon generator; assay of xenon sample counting techniques; crystal diffraction neutron spectrometer; C{sup 12} cross sections measurements; magnetic spectrometer; scintillation spectroscopy; improved pile structure; criticality for the untamped 16 inch spherical reactor; exponential experiments; large scale pile structure; and operational pile physics.
Date: December 6, 1951
Partner: UNT Libraries Government Documents Department

100 Areas technical activities report -- Physics, October 1946

Description: The D Pile was down five times for scheduled shutdowns. The fifth shutdown was of short duration for the purpose of discharging temporary ``P`` columns. Details of the shutdowns are given. Three new bismuth columns were established, Special Requests were charged into seven tubes and three Special Requests were discharged. Three tubes were charged with four-inch slugs. The power level of the F Pile has been corrected for the discrepancy noted last month. Material for irradiation under the Special Request program was charged into six tubes and the B experimental hole during the month. The effect of poison columns and rods on the temperature distribution of the pile was checked for the overall content of the pile. The F Pile gained two in hours in cold, clean reactivity during the month if allowance is made for xenon poison values corresponding to 190 MW for the beginning of the month and 200 MW at the end of the month. The graphite stringer removed from the ``D`` test hole of the D Pile on 3-12-46 was studied physical radiation effects.
Date: November 6, 1946
Creator: Gast, P. F.
Partner: UNT Libraries Government Documents Department

100% foundry compatible packaging and full wafer release and die separation technique for surface micromachined devices

Description: A completely foundry compatible chip-scale package for surface micromachines has been successfully demonstrated. A pyrex (Corning 7740) glass cover is placed over the released surface micromachined die and anodically bonded to a planarized polysilicon bonding ring. Electrical feedthroughs for the surface micromachine pass underneath the polysilicon sealing ring. The package has been found to be hermetic with a leak rate of less than 5 x 10{sup {minus}8} atm cm{sup {minus}3}/s. This technology has applications in the areas of hermetic encapsulation and wafer level release and die separation.
Date: April 6, 2000
Creator: Oliver, Andrew D. & Matzke, Carolyn M.
Partner: UNT Libraries Government Documents Department

AZ-101 Mixer Pump Test MT Fury Suspended Solids Profiler Application and Testing

Description: Describes the radiation testing and calibration of the AZ-101 tank suspended solids profiler unit mounted on 6 tank riser 24A. The Mt. Fury Suspended Solids Profiler (SSP) is a microprocessor-controlled instrument that measures the turbidity of solid-liquid suspensions and sludges. The profiler is used commercially for the monitoring and control of clarifiers and thickeners in waste treatment, mining, pulp and paper, and other industrial processing facilities. The instrument includes a three inch diameter probe, a Kynar coated coaxial cable, a reel assembly with a clutch and drive shaft, a stepper motor, and electronics. The instrument measures insoluble or suspended solids content in liquids by transmitting infrared energy at a wavelength of 935 nm and measuring the extent of backscatter. This frequency is not affected by solution color. There are two detectors that allow the instrument to operate over a broad range of concentrations, from clear liquids to light sludges.
Date: January 6, 2000
Creator: MACLEAN, G.T.
Partner: UNT Libraries Government Documents Department

The 13th International Symposium on Relations between Homogeneous and Heterogeneous Catalysis -- AnIntroduction

Description: Over forty years, there have been major efforts to aim at understanding the properties of surfaces, structure, composition, dynamics on the molecular level and at developing the surface science of heterogeneous and homogeneous catalysis. Since most catalysts (heterogeneous, enzyme and homogeneous) are nanoparticles, colloid synthesis methods were developed to produce monodispersed metal nanoparticles in the 1-10 nm range and controlled shapes to use them as new model catalyst systems in two-dimensional thin film form or deposited in mezoporous three-dimensional oxides. Studies of reaction selectivity in multipath reactions (hydrogenation of benzene, cyclohexene and crotonaldehyde) showed that reaction selectivity depends on both nanoparticle size and shape. The oxide-metal nanoparticle interface was found to be an important catalytic site because of the hot electron flow induced by exothermic reactions like carbon monoxide oxidation.
Date: February 6, 2008
Creator: Somorjai, Gabor A.
Partner: UNT Libraries Government Documents Department

[1974 Concert band tour member]

Description: Photograph of a North Texas State University bassoon player and member of the 1974 concert band tour. In this image, the unidentified musician is wearing his uniform and standing in front of a long sheet of paper.
Date: February 6, 1974
Partner: UNT Libraries Special Collections

1998 Chemical Technology Division Annual Technical Report.

Description: The Chemical Technology (CMT) Division is a diverse technical organization with principal emphases in environmental management and development of advanced energy sources. The Division conducts research and development in three general areas: (1) development of advanced power sources for stationary and transportation applications and for consumer electronics, (2) management of high-level and low-level nuclear wastes and hazardous wastes, and (3) electrometallurgical treatment of spent nuclear fuel. The Division also performs basic research in catalytic chemistry involving molecular energy resources, mechanisms of ion transport in lithium battery electrolytes, and the chemistry of technology-relevant materials. In addition, the Division operates the Analytical Chemistry Laboratory, which conducts research in analytical chemistry and provides analytical services for programs at Argonne National Laboratory (ANL) and other organizations. Technical highlights of the Division's activities during 1998 are presented.
Date: August 6, 1999
Creator: Ackerman, J.P.; Einziger, R.E.; Gay, E.C.; Green, D.W. & Miller, J.F.
Partner: UNT Libraries Government Documents Department