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captions transcript

[News Clip: Counterfeit bills]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: 2003-11-30/..
Duration: 1 minute 30 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Counterfeit bills]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: 2003-11-30/..
Duration: 25 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections
open access

Prospects for Investigating Unusual Nuclear Reaction Environments Using the National Ignition Facility

Description: The standard capsule design1 and other laser plasma targets at the National Ignition Facility offer the possibility of generating and studying thermal rates for significant astrophysical fusion reactions such as {sup 3}He({sup 3}He,2p){alpha}, {sup 7}Be(p,{gamma})B, and {sup 15}N(p,{alpha}){sup 12}C. At present the ''S'' factors for these reactions are determined either by extrapolation from higher energy scattering data or by underground laboratory, low event rate experiments such as at LUNA on un-ionized atoms with concomitantly large screening corrections. The ability to directly generate astrophysical fusion reactions in thermonuclear plasmas will be complemented by new, ab initio, ''no frozen core'' detailed shell model predictions for such light ion reactions. In addition, the expected fluence of neutrons from the main D + T {yields} {alpha} burn reaction, is high enough to drive 10-20% of seeded spectator nuclei into excited states via (n,n') reactions. Furthermore, the {approx}2% ''minority'' D + D {yields} {sup 3}He + n can drive reactions pertinent to the r, s, and p process nucleosynthesis of heavy elements, including branches that pass through excited states with t > 10 ps, that can be studied using particle spectroscopy and radiochemistry. Additionally, for the first time, it will be possible to measure the effects of plasma screening on thermonuclear reactions. In the latter arena it will be possible to address the controversy of whether or not there are significant quantum corrections to Salpeter screening. Radiochemistry measurements of noble gas end species can be made with very high efficiency with only {approx} 10{sup 4} atoms required. Solid collection systems are being developed as well (with 10 atoms required at present). Because the capsule is essentially thin to neutrons, the reaction rate on an advected set of marker nuclei is a linear functional of the neutron source distribution. Determining this source function is thus computationally …
Date: September 30, 2003
Creator: Libby, S B; Tabak, M; Hoffmann, R D; Stoyer, M A; Haan, S W; Hatchett, S P et al.
Partner: UNT Libraries Government Documents Department
open access

High Performance Diskless Linux Workstations in AX-Division

Description: AX Division has recently installed a number of diskless Linux workstations to meet the needs of its scientific staff for classified processing. Results so far are quite positive, although problems do remain. Some unusual requirements were met using a novel, but simple, design: Each diskless client has a dedicated partition on a server disk that contains a complete Linux distribution.
Date: September 30, 2003
Creator: Councell, E & Busby, L
Partner: UNT Libraries Government Documents Department
open access

Physical and Liquid Chemical Simulant Formulations for Transuranic Waste in Hanford Single-Shell Tanks

Description: CH2M HILL Hanford Group, Inc. (CH2M HILL) is in the process of identifying and developing supplemental process technologies to accelerate the tank waste cleanup mission. A range of technologies is being evaluated to allow disposal of Hanford waste types, including transuranic (TRU) process wastes. Ten Hanford single-shell tanks (SSTs) have been identified whose contents may meet the criteria for designation as TRU waste: the B-200 series (241-B-201, -B-202, -B 203, and B 204), the T-200 series (241-T-201, T 202, -T-203, and -T-204), and Tanks 241-T-110 and -T-111. CH2M HILL has requested vendor proposals to develop a system to transfer and package the contact-handled TRU (CH-TRU) waste retrieved from the SSTs for subsequent disposal at the Waste Isolation Pilot Plant (WIPP). Current plans call for a modified ''dry'' retrieval process in which a liquid stream is used to help mobilize the waste for retrieval and transfer through lines and vessels. This retrieval approach requires that a significant portion of the liquid be removed from the mobilized waste sludge in a ''dewatering'' process such as centrifugation prior to transferring to waste packages in a form suitable for acceptance at WIPP. In support of CH2M HILL's effort to procure a TRU waste handling and packaging process, Pacific Northwest National Laboratory (PNNL) developed waste simulant formulations to be used in evaluating the vendor's system. For the SST CH-TRU wastes, the suite of simulants includes (1) nonradioactive chemical simulants of the liquid fraction of the waste, (2) physical simulants that reproduce the important dewatering properties of the waste, and (3) physical simulants that can be used to mimic important rheological properties of the waste at different points in the TRU waste handling and packaging process. To validate the simulant formulations, their measured properties were compared with the limited data for actual TRU waste samples. PNNL …
Date: July 30, 2003
Creator: Rassat, Scot D.; Bagaasen, Larry M.; Mahoney, Lenna A.; Russell, Renee L.; Caldwell, Dustin D. & Mendoza, Donaldo P.
Partner: UNT Libraries Government Documents Department
open access

The 75As(n,2n) Cross Sections into the 74As Isomer and Ground State

Description: The {sup 75}As(n, 2n) cross section for the population of the T{sub 1/2} = 26.8-ns isomer at E{sub x} = 259.3 keV in {sup 74}As has been measured as a function of incident neutron energy, from threshold to E{sub n} = 20 MeV. The cross section was measured using the GEANIE spectrometer at LANSCE/WNR. For convenience, the {sup 75}As(n, 2n) population cross section for the {sup 74}As ground state has been deduced as the difference between the previously-known (n, 2n) reaction cross section and the newly measured {sup 75}As(n, 2n){sup 74}As{sup m} cross section. The (n, 2n) reaction, ground-state, and isomer population cross sections are tabulated in this paper.
Date: June 30, 2003
Creator: Younes, W; Garrett, P E; Becker, J A; Bernstein, L A; Ormand, W E; Dietrich, F S et al.
Partner: UNT Libraries Government Documents Department
open access

Spatial Coherence of Synchrotron Radiation

Description: Synchrotron Radiation (SR) has been widely used since the 80's as a tool for many applications of UV, soft X rays and hard X rays in condensed matter physics, chemistry and biology. The evolution of SR sources towards higher brightness has led to the design of low-emittance electron storage rings (emittance is the product of beam size and divergence), and the development of special source magnetic structures, as undulators. This means that more and more photons are available on a narrow bandwidth and on a small collimated beam; in other words there is the possibility of getting a high power in a coherent beam. In most applications, a monochromator is used, and the temporal coherence of the light is given by the monochromator bandwidth. With smaller and smaller sources, even without the use of collimators, the spatial coherence of the light has become appreciable, first in the UV and soft X ray range, and then also with hard X rays. This has made possible new or improved experiments in interferometry, microscopy, holography, correlation spectroscopy, etc. In view of these recent possibilities and applications, it is useful to review some basic concepts about spatial coherence of SR, and its measurement and applications. In particular we show how the spatial coherence properties of the radiation in the far field can be calculated with simple operations from the single-electron amplitude and the electron beam angular and position spreads. The gaussian approximation will be studied in detail for a discussion of the properties of the far field mutual coherence and the estimate of the coherence widths, and the comparison with the VanCittert-Zernike limit.
Date: October 30, 2003
Creator: Marchesini, S & Coisson, R
Partner: UNT Libraries Government Documents Department
open access

Laboratory Testing of Bulk Vitrified and Steam Reformed Low-Activity Waste Forms to Support A Preliminary Risk Assessment for an Integrated Disposal Facility

Description: Laboratory testing was conducted on bulk vitrified and steam reformed waste forms to supply the input parameters needed for reactive chemical transport calculations with the Subsurface Transport Over Reactive Multiphases (STORM) code. This same code was used to conduct the 2001 ILAW performance assessment. The required input parameters for both waste forms are derived from a mechanistic model that describes the effect of solution chemistry on contaminant release rates. The single-pass flow-through test was the principal method used to obtain these input parameters, supplemented by product consistency test measurements and physical property measurements.
Date: September 30, 2003
Creator: McGrail, B. Peter; Pierce, Eric M.; Schaef, Herbert T.; Rodriguez, Elsa A.; Steele, Jackie L.; Owen, Antionette T. et al.
Partner: UNT Libraries Government Documents Department
open access

Boron Addition to Model Austenitic Steels and void Nucleation

Description: Fe-15Cr-16Ni, -0.25Ti, -500appmB, and -0.25Ti-500appmB have been irradiated in FFTF/MOTA over a wide range of dose rate which covers more than two orders difference in magnitude, within the very limited temperature range of 387-444 C. The effects of dose rate and boron addition on swelling are examined. Lower dose rates increase the swelling by shortening the incubation dose for swelling. Addition of boron does not significantly change the swelling nor the dose rate dependence of swelling for both the ternary and Ti-modified alloy. The helium pressure of cavities is found to be much smaller than the surface tension at every irradiation condition including the lowest dose and dose rate, helium generated by boron transmutant does not play any role in cavity formation in this experiment. Cavities form without helium. The difference in cavity morphology by boron addition is most likely caused by formation of borides and by lithium.
Date: October 30, 2003
Creator: Okita, T; Wolfer, W G; Garner, F A & Sekimura, N
Partner: UNT Libraries Government Documents Department
open access

Recommendations for Advanced Design Mixer Pump Operation in Savannah River Site Tank 18F

Description: This report discusses technical issues and presents recommendations for operating the advanced design mixer pump (ADMP) in Tank 18 at the Savannah River Site (SRS). Also presented are the results obtained from simulated scaled pump-down tests carried out in the 1/4-scale double shell tank (DST) test facility at Pacific Northwest National Laboratory (PNNL). The work was conducted for the DOE Tanks Focus Area (TFA) by the Retrieval Process Development and Enhancement (RPD&E) program. The ability of the Tank 18 retrieval system to mobilize the solid waste and transport it through the retrieval pump, efficiently removing the solids from the tank, are evaluated.
Date: October 30, 2003
Creator: Enderlin, Carl W.; Terrones, Guillermo; Bates, Cameron J.; Hatchell, Brian K. & Adkins, Brannen
Partner: UNT Libraries Government Documents Department
open access

Studies of Electron Transport and Isochoric Heating and Their Applicability to Fast Ignition

Description: Experimental measurements of electron transport and isochoric heating in 100 J, 1 ps laser irradiation of solid A1 targets are presented. Modeling with a hybrid PIC code is compared with the data and good agreement is obtained using a heuristic model for the electron injection. The relevance for fast ignition is discussed.
Date: October 30, 2003
Creator: Key, M. H.; Amiranoff, F.; Andersen, C.; Batani, D.; Baton, S. D.; Cowan, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Carcinogens formed when Meat is Cooked

Description: Diet has been associated with varying cancer rates in human populations for many years, yet the causes of the observed variation in cancer patterns have not been adequately explained (Wynder et al. 1977). Along with the effect of diet on human cancer incidence is the strong evidence that mutations are the initiating events in the cancer process (Vogelstein et al. 1992). Foods, when heated, are a good source of genotoxic carcinogens that very likely are a cause for some of these events(Doll et al. 1981). These carcinogens fall into two chemical classes: heterocyclic aromatic amines (HAA) and polycyclic aromatic hydrocarbons (PAH). There is ample evidence that many of these compounds are complete carcinogens in rodents(El-Bayoumy et al. 1995; Ohgaki et al. 1991). Heterocyclic aromatic amines are among the most potent mutagenic substances ever tested in the Ames/Salmonella mutagenicity test (Wakabayashi et al. 1992). Both classes of carcinogen cause tumors in rodents at multiple sites, (El-Bayoumy et al. 1995; Ohgaki et al. 1991) many of which are common tumor sites in people on a Western diet. An HAA, PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine), and a PAH, B[a]P (benzo[a]pyrene), of comparable carcinogenic potency caused mammary gland tumors in a feeding study in female rats (El-Bayoumy et al. 1995). In addition, PhIP has recently been shown to cause carcinomas in the prostate of the male rat (Shirai et al. 1997). Complementing the rodent cancer studies are numerous human case-control and prospective studies suggesting a relationship between overheated beef, chicken, and lamb, and cancer of the colon, breast, prostate, and stomach (Sinha et al. 1999; Ward et al. 1997; Zheng et al. 1998).
Date: May 30, 2003
Creator: Felton, J S; Salmon, C P & Knize, M G
Partner: UNT Libraries Government Documents Department
open access

Underwater Determination of Radionuclide Levels in 105-KE Basin Floor and Walls Using a Gamma-Ray Detector System

Description: Activities to remove spent fuel, sludge and debris from K East Basin have begun. Once all the radioactive hazards (i.e., fuel, sludge and debris) are removed from the basin, the basin water will be removed and the basin will be turned over to a deactivation and decommission contractor. However, the specific approach to achieving this end state is dependent on knowledge of contamination levels in the concrete walls and floor once the water is removed. PNNL researchers have developed a one-of-a-kind technology for performing non-destructive evaluation of the highly contaminated K East fuel storage basin for the purpose of determining concrete contamination levels from selected wall and floor locations below the basin waterline.
Date: September 30, 2003
Creator: Arthur, Richard J.; Schlahta, Stephan N.; Scherpelz, Robert I.; MacFarlan, Paul J. & Catalan, Michael A.
Partner: UNT Libraries Government Documents Department
open access

High-Efficiency Steam Electrolyzer

Description: A hydrogen economy will require readily available and affordable hydrogen fuel. Current methods of hydrogen production do not fulfill these requirements. We are working on an electrolyzer system that can provide distributed hydrogen production while taking advantage of the nation's existing natural gas infrastructure. Electrolysis is a promising hydrogen production technology both because of its ability to produce pure hydrogen from water and because it does not require large, centralized plants. Unlike other technologies, the cost of hydrogen production scales well from larger to smaller systems. Electrolysis units could be widely distributed and scaled to meet the hydrogen requirements of different users such as individual households, local fueling stations and industrial facilities. A significant drawback to traditional electrolysis is the large electricity consumption required to convert water to hydrogen and oxygen. The electricity requirements mean such systems are expensive to operate. In addition, if the electricity is provided from coal or gas-fired power plants, electrolytic hydrogen production does not mitigate greenhouse gas emissions. The concept described in this report is intended to resolve some of the problems associated with electrolytic hydrogen production. By utilizing natural gas in place of air in the anode compartment in a solid oxide electrolyzer, the electricity requirements of the system are greatly reduced. The system has the capability to produce pure hydrogen, or hydrogen humidified to levels appropriate for direct use in a PEM fuel cell. With inherent electrochemical compression, the requirement for external compression for pressurization could be reduced. This technology offers numerous advantages for distributed hydrogen production of stationary and transportation hydrogen fuel cells. Our preliminary calculations indicate that using this concept, hydrogen could be produced at a cost competitive with gasoline (on a per gallon equivalent basis) while also lowering carbon dioxide emissions.
Date: June 30, 2003
Creator: Vance, A L; Trent, J W; See, E F & Glass, R S
Partner: UNT Libraries Government Documents Department
open access

Health Impacts from Acute Radiation Exposure

Description: Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.
Date: September 30, 2003
Creator: Strom, Daniel J.
Partner: UNT Libraries Government Documents Department
open access

Incorporation of Chemical Reactions into Building-scale Flow

Description: Many hazardous atmospheric releases involve chemical reactions that occur within a few kilometers of the source. Reactions with commonly occurring atmospheric compounds such as the OH radical, can transform and potentially neutralize original release compounds. Especially in these cases, accurately resolving flow around nearby structures and over surrounding topography can be critical to correctly predicting material dispersion, and thus, the extent of any hazard. Accurate prediction of material dispersion around complex geometries near the source of an atmospheric release requires high-resolution computation. Further complications arise if the compounds released undergo chemical reactions which could alter the extent of the main plume. The reaction products form dispersion patterns separate from, and often more complicated than, the original plume. Directions for future work include expanding the library of chemical reaction mechanisms, adding capabilities for aqueous and heterogeneous reactions, and integrating this model within larger-scale models. We plan that the larger-scale models will provide meteorological and chemical boundary conditions, and that this model could provide a source term in larger-scale models, both for momentum and for dispersed compounds.
Date: October 30, 2003
Creator: Humphreys, T D; Jayaweera, T M & Lee, R L
Partner: UNT Libraries Government Documents Department
open access

Ultrasonic Examination of Double-Shell Tank 241-AP-103. Examination Completed April 2003.

Description: COGEMA Engineering Corporation (COGEMA), under contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic examination of selected portions of Double-Shell Tank 241-AP-103. PNNL is responsible for preparing a report(s)that describes the results of the COGEMA ultrasonic examinations.
Date: June 30, 2003
Creator: Pardini, Allan F. & Posakony, Gerald J.
Partner: UNT Libraries Government Documents Department
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