Cryogenic Simulations of Tissue Freezing (open access)

Cryogenic Simulations of Tissue Freezing

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Date: October 17, 2000
Creator: DYKHUIZEN,RONALD C. & SAMBANIS,A.
Object Type: Article
System: The UNT Digital Library
Development of probabilistic RESRAD computer codes for NRC decommissioning and license termination applications. (open access)

Development of probabilistic RESRAD computer codes for NRC decommissioning and license termination applications.

In 1999, the US Nuclear Regulatory Commission (NRC) tasked Argonne National Laboratory to modify the existing RESRAD and RESRAD-BUILD codes to perform probabilistic, site-specific dose analysis for use with the NRC's Standard Review Plan for demonstrating compliance with the license termination rule. The RESRAD codes have been developed by Argonne to support the US Department of Energy's (DOEs) cleanup efforts. Through more than a decade of application, the codes already have established a large user base in the nation and a rigorous QA support. The primary objectives of the NRC task are to: (1) extend the codes' capabilities to include probabilistic analysis, and (2) develop parameter distribution functions and perform probabilistic analysis with the codes. The new codes also contain user-friendly features specially designed with graphic-user interface. In October 2000, the revised RESRAD (version 6.0) and RESRAD-BUILD (version 3.0), together with the user's guide and relevant parameter information, have been developed and are made available to the general public via the Internet for use.
Date: October 17, 2000
Creator: Chen, S. Y.; Yu, C.; T., Mo. & Trottier, C.
Object Type: Article
System: The UNT Digital Library
An approach for dealing with large errors. (open access)

An approach for dealing with large errors.

Numerical functions or equivalent algorithms are commonly used to derive estimates for physical quantities that can be expressed in terms of more fundamental physical parameters. It is shown that in situations where large uncertainties (errors) are involved in these parameters, or where error amplification occurs through severe non-linearity of the functions, conventional deterministic techniques for calculating the derived quantities and estimating their errors can lead to erroneous results. Instead, it is necessary to resort to a probabilistic approach and thereby obtain estimates for mean values and variances of the derived quantities through Monte Carlo simulation in order to preserve the essential information without distortion. The correct choice for a probability distribution is suggested by the inherent nature of the random variable in question. Examples are given from the analysis of radioactivity decay, the shielding of penetrating radiation, and the derivation of nuclear reaction rates that are used in astrophysical calculations to model nucleosynthesis of the elements in stellar explosions. Subsequent analyses that use these derived quantities must also be carried out in a probabilistic manner to insure that the obtained results will reflect the underlying information properly.
Date: October 17, 2001
Creator: Smith, D. L.; Naberejnev, D. G. & Van Wormer, L. A.
Object Type: Report
System: The UNT Digital Library
Thermal Stability and Aging Characteristics of Chromate Conversion Coatings on Aluminum Alloy 2024-T3 (open access)

Thermal Stability and Aging Characteristics of Chromate Conversion Coatings on Aluminum Alloy 2024-T3

XANES and electrochemical impedance spectroscopes were used in parallel to correlate the amount of Cr(VI) in chromate conversion coatings (CCC) on Al 2024 and their corrosion resistance in order to understand the degradation mechanisms upon aging or heating. Cr(VI) species appear to be immobilized for temperatures higher than 80 C due to dehydration. CCC are shown to be dynamic in the first month of aging with no significant dehydration. Another degradation mechanism involving chemical changes is to be considered.
Date: October 17, 1999
Creator: Laget, V.; Jeffcoate, C.; Isaacs, H. S. & Buchheit, R. G.
Object Type: Article
System: The UNT Digital Library
Design of a 16T Nb{sub 3}Sn twin dipole with a window-frame conductor layout (open access)

Design of a 16T Nb{sub 3}Sn twin dipole with a window-frame conductor layout

A simplified design study of a 16T Nb{sub 3}Sn twin bore accelerator dipole magnet is presented. The philosophy behind the study is to design a high field magnet with a coil structure optimized for a reasonable Lorentz-load and easy of construction. The coils are of the rectangular window-frame type with modular flat pancake windings, thus eliminating the need for complex coil return ends. The magnetic and structural design Is presented and a comparison is made with existing coil layouts for high field magnets.
Date: October 17, 1994
Creator: van Oort, J. M. & Scanlan, R. M.
Object Type: Article
System: The UNT Digital Library
High-temperature, radiation-tolerant electronics for the MMW (Multi-megawatt) Space Reactor Program (open access)

High-temperature, radiation-tolerant electronics for the MMW (Multi-megawatt) Space Reactor Program

One of the objectives of the Multi-Megawatt (MMW) space reactor program is to determine, within the next five years, what types of power electronic devices would be suitable for MMW space power applications. Suitable devices must be able to withstand high temperatures and high radiation fields. After investigating the literature on solid state device and miniature vacuum tube technologies, we have concluded that the miniature vacuum tube technology is, currently, the most promising. The main reason for choosing this technology, is because miniature vacuum tubes can operate at very high temperatures (775 K or potentially higher) and are tolerant to very high neutron fluence and gamma dose. Although there are still problems to be solved before miniature vacuum tubes can be used, the time required for their development will be much shorter than the five year period required by the MMW space reactor program. 13 refs., 3 figs., 3 tabs.
Date: October 17, 1986
Creator: Yee, J. H.; Orvis, William J.; McConaghy, C. & Ciarlo, D. R.
Object Type: Report
System: The UNT Digital Library
Functional and design requirements for construction of framed fabric structures in the CWC (open access)

Functional and design requirements for construction of framed fabric structures in the CWC

The purpose of this document is to supply the applicable functional design requirements associated with construction and use of framed fabric structures in the Central Waste Complex
Date: October 17, 1995
Creator: Irwin, R. M.
Object Type: Report
System: The UNT Digital Library
Winter Fuels Report: Week Ending October 11, 1991. [Contains Glossary] (open access)

Winter Fuels Report: Week Ending October 11, 1991. [Contains Glossary]

This Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and State and local governments on the following topics: distillate fuel oil net production, imports and stocks for all Petroleum Administration for Defense Districts (PADD) and product supplied on a US level; propane net production, imports and stocks for PADD's 1, 2, and 3; natural gas supply and disposition and underground storage for the United States and consumption for all PADD's; residential and wholesale pricing data for propane and heating oil for those States participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil and petroleum price comparisons for the United States and selected cities; and US total heating degree-days by city. 37 figs., 13 tabs.
Date: October 17, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
TMX, a new facility (open access)

TMX, a new facility

As a mirror fusion facility, the Tandem Mirror Experiment (TMX) at the Lawrence Livermore Laboratory (LLL) is both new and different. It utilizes over 23,000 ft/sup 2/ of work area in three buildings and consumes over 14 kWh of energy with each shot. As a systems design, the facility is broken into discreet functional regions. Among them are a mechanical vacuum pumping system, a liquid-nitrogen system, neutral-beam and magnet power supplies, tiered structures to support these supplies, a neutron-shielded vacuum vessel, a control area, and a diagnostics area. Constraints of space, time, and cost have all affected the design.
Date: October 17, 1977
Creator: Thomas, S. R., Jr.
Object Type: Article
System: The UNT Digital Library
Flow through porous media from a nuclear cavity (open access)

Flow through porous media from a nuclear cavity

The transport of fluid from the cavity formed by an underground nuclear explosion is investigated. Driven by the high cavity pressure, steam and noncondensing gas enter the surrounding porous medium. Their subsequent motion through the medium is described and the extent of penetration determined. The relations governing the transport are presented. An implicit iterative computational method is developed. The relative merits of this technique are discussed. The method is applied to a nuclear test. Results of calculations are presented and discussed.
Date: October 17, 1976
Creator: Morrison, F. A., Jr.
Object Type: Article
System: The UNT Digital Library
Observation and study of baryonic B decays: B -> D(*) p pbar, D(*) p pbar pi, and D(*) p pbar pi pi (open access)

Observation and study of baryonic B decays: B -> D(*) p pbar, D(*) p pbar pi, and D(*) p pbar pi pi

We present a study of ten B-meson decays to a D{sup (*)}, a proton-antiproton pair, and a system of up to two pions using BABAR's data set of 455 x 10{sup 6} B{bar B} pairs. Four of the modes {bar B}{sup 0} {yields} D{sup 0}p{bar p}, {bar B}{sup 0} {yields} D*{sup 0}p{bar p}, {bar B}{sup 0} {yields} D{sup +}p{bar p}{pi}{sup -}, {bar B}{sup 0} {yields} D{sup ast+}p{bar p}{pi}{sup -} are studied with improved statistics compared to previous measurements; six of the modes (B{sup -} {yields} D{sup 0}p{bar p}{pi}{sup -}, B{sup -} {yields} D*{sup 0}p{bar p}{pi}{sup -}, {bar B}{sup 0} {yields} D{sup 0}p{bar p}{pi}{sup -}{pi}{sup +}, {bar B}{sup 0} {yields} D*{sup 0}p{bar p}{pi}{sup -}{pi}{sup +}, B{sup -} {yields} D{sup +}p{bar p}{pi}{sup -}{pi}{sup -}, B{sup -} {yields} D{sup ast+}p{bar p}{pi}{sup -}{pi}{sup -}) are first observations. The branching fractions for 3- and 5-body decays are suppressed compared to 4-body decays. Kinematic distributions for 3-body decays show non-overlapping threshold enhancements in m(p{bar p}) and m(D{sup (*)0}p) in the Dalitz plots. For 4-body decays, m(p{pi}{sup -}) mass projections show a narrow peak with mass and full width of (1497.4 {+-} 3.0 {+-} 0.9)MeV/c{sup 2} and (47 {+-} 12 {+-} 4)MeV/c{sup 2}, respectively, where the first …
Date: October 17, 2009
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
Search for a Narrow Resonance in e e- to Four Lepton Final States (open access)

Search for a Narrow Resonance in e e- to Four Lepton Final States

Motivated by recent models proposing a hidden sector with {approx} GeV scale force carriers, we present a search for a narrow dilepton resonance in 4 lepton final states using 536 fb{sup -1} collected by the BABAR detector. We search for the reaction, e{sup +}e{sup -} {yields} W{prime}W{prime} {yields} (l{sup +}l{sup -})(l{prime}{sup +}l{prime}{sup -}), where the leptons carry the full 4-momentum and the two dilepton pair invariant masses are equal. We do not observe a significant signal and we set 90% upper limits of {sigma}(e{sup +}e{sup -} {yields} W{prime}W{prime} {yields} e{sup +}e{sup -}e{sup +}e{sup -}) < (15-70) ab, {sigma}(e{sup +}e{sup -} {yields} W{prime}W{prime} {yields} e{sup +}e{sup -}{mu}{sup +}{mu}{sup -} < (15-40) ab, and {sigma}(e{sup +}e{sup -} {yields} W{prime}W{prime} {yields} {mu}{sup +}{mu}{sup -}{mu}{sup +}{mu}{sup -}) < 11-17) ab in the W{prime} mass range between 0.24 and 5.3GeV/c{sup 2}. Under the assumption that the W{prime} coupling to electrons and muons is the same, we obtain a combined upper limit of {sigma}e{sup +}e{sup -} {yields} W{prime}W{prime} {yields} l{sup +}l{sup -}l{prime}{sup +}l{prime}{sup -} < (25-60) ab. Using these limits, we constrain the product of the SM-dark sector mixing and the dark coupling constant in the case of a non-Abelian Higgsed dark sector.
Date: October 17, 2009
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
A Search for Invisible Decays of the Upsilon(1S) (open access)

A Search for Invisible Decays of the Upsilon(1S)

We search for invisible decays of the {Upsilon}(1S) meson using a sample of 91.4 x 10{sup 6} {Upsilon}(3S) mesons collected at the BABAR/PEP-II B Factory. We select events containing the decay {Upsilon}(3S) {yields} {pi}{sup +}{pi}{sup -} {Upsilon}(1S) and search for evidence of an undetectable {Upsilon}(1S) decay recoiling against the dipion system. We set an upper limit on the branching fraction {Beta}({Upsilon}(1S) {yields} invisible) < 3.0 x 10{sup ?4} at the 90% confidence level.
Date: October 17, 2009
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of D0-D0bar Mixing using the Ratio of D0->K-pi and K-K Lifetimes (open access)

Measurement of D0-D0bar Mixing using the Ratio of D0->K-pi and K-K Lifetimes

We measure the rate of D{sup 0}-{bar D}{sup 0} mixing with the observable y{sub CP} = ({tau}{sub K{pi}}/{tau}{sub KK}) - 1, where {tau}{sub KK} and {tau}{sub K{pi}} are respectively the mean lifetimes of CP-even D{sup 0} {yields} K{sup +}K{sup -} and CP-mixed D{sup 0} {yields} K{sup -}{pi}{sup +} decays, using a data sample of 384 fb{sup -1} collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B Factory. From a sample of D{sup 0} and {bar D}{sup 0} decays where the initial flavor of the decaying meson is not determined, we obtain y{sub CP} = [1.12 {+-} 0.26(stat) {+-} 0.22(syst)]%, which excludes the no-mixing hypothesis at 3.3{sigma}, including both statistical and systematic uncertainties. This result is in good agreement with a previous BABAR measurement of y{sub CP} obtained from a sample of D*{sup +} {yields} D{sup 0}{pi}{sup +} events, where the D{sup 0} decays to K{sup -}{pi}{sup +}, K{sup +}K{sup -}, and {pi}{sup +}{pi}{sup -}, which is disjoint with the untagged D{sup 0} events used here. Combining the two results taking into account statistical and systematic uncertainties, where the systematic uncertainties are assumed to be 100% correlated, we find y{sub CP} = [1.16 {+-} 0.22(stat) {+-} 0.18(syst)]%, which excludes …
Date: October 17, 2009
Creator: Aubert, B.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X. et al.
Object Type: Article
System: The UNT Digital Library