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16,032 Matching Results
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Performance Demonstration Program Plan for Nondestructive Assay of Drummed Wastes for the TRU Waste Characterization Program
Each testing and analytical facility performing waste characterization activities for the Waste Isolation Pilot Plant (WIPP) participates in the Performance Demonstration Program (PDP) to comply with the Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC) (DOE/WIPP-02-3122) and the Quality Assurance Program Document (QAPD) (CBFO-94-1012). The PDP serves as a quality control check for data generated in the characterization of waste destined for WIPP. Single blind audit samples are prepared and distributed to each of the facilities participating in the PDP. The PDP evaluates analyses of simulated headspace gases, constituents of the Resource Conservation and Recovery Act (RCRA), and transuranic (TRU) radionuclides using nondestructive assay (NDA) techniques.
Date:
April 1, 2009
Creator:
/A, N
Object Type:
Report
System:
The UNT Digital Library
Scaled Experimental Modeling of VHTR Plenum Flows
Abstract The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. Various scaled heated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification (“thermal striping”) in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the density effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower …
Date:
April 1, 2007
Creator:
15, ICONE
Object Type:
Article
System:
The UNT Digital Library
Development of Advanced Wear and Corrosion Resistant Systems Through Laser Surface Alloying and Materials Processing
The stability of tungsten carbide particles in iron-rich and nickel-rich liquid during the laser surface alloying (LSA) process was investigated. Kinetic calculations indicate a rapid dissolution of tungsten carbide particles in iron-rich liquid, as compared with the dissolution rate in nickel-rich liquid. Optical microscopy indicated a heterogeneous microstructure around the tungsten particles that is in agreement with concentration gradients predicted by kinetic calculation. The work demonstrates the applicability of computational thermodynamics and kinetic models for the LSA process.
Date:
April 1, 2002
Creator:
A, Babu S S Martukanitz R P Parks K D David S
Object Type:
Article
System:
The UNT Digital Library
Pressure-induced Breaking of Equilibrium Flux Surfaces in the W7AS Stellarator
Calculations are presented for two shots in the W7AS stellarator which differ only in the magnitude of the current in the divertor control coil, but have very different values of experimentally attainable β (<β> ≈ 2.7% versus <β> ≈ 1.8%). Equilibrium calculations find that a region of chaotic magnetic field line trajectories fills approximately the outer 1/3 of the cross-section in each of these configurations. The field lines in the stochastic region are calculated to behave as if the flux surfaces are broken only locally near the outer midplane and are preserved elsewhere. The calculated magnetic field line diffusion coefficients in the stochastic regions for the two shots are consistent with the observed differences in the attainable β, and are also consistent with the differences in the reconstructed pressure profiles.
Date:
April 24, 2007
Creator:
A. Reiman, M.C. Zarnstorff, D. Monticello, A. Weller, J. Geiger, and the W7-AS Team
Object Type:
Article
System:
The UNT Digital Library
Emittance Reduction between EBIS LINAC and Booster by Electron Beam Cooling - Is Single Pass Cooling Possible?
N/A
Date:
April 1, 2008
Creator:
A., Hershcovitch
Object Type:
Report
System:
The UNT Digital Library
Optical simulations of the ion beam emittance growth in different types of a gridded lens
N/A
Date:
April 1, 2007
Creator:
A., Pikin
Object Type:
Report
System:
The UNT Digital Library
Cancellation of the Chromatic Effects with proper Field Profile
N/A
Date:
April 1, 2004
Creator:
A., Ruggiero
Object Type:
Report
System:
The UNT Digital Library
Astrophysical Gyrokinetics: Kinetic and Fluid Turbulent Cascades In Magentized Weakly Collisional Plasmas
This paper presents a theoretical framework for understanding plasma turbulence in astrophysical plasmas. It is motivated by observations of electromagnetic and density fluctuations in the solar wind, interstellar medium and galaxy clusters, as well as by models of particle heating in accretion disks. All of these plasmas and many others have turbulentmotions at weakly collisional and collisionless scales. The paper focuses on turbulence in a strong mean magnetic field. The key assumptions are that the turbulent fluctuations are small compared to the mean field, spatially anisotropic with respect to it and that their frequency is low compared to the ion cyclotron frequency. The turbulence is assumed to be forced at some system-specific outer scale. The energy injected at this scale has to be dissipated into heat, which ultimately cannot be accomplished without collisions. A kinetic cascade develops that brings the energy to collisional scales both in space and velocity. The nature of the kinetic cascade in various scale ranges depends on the physics of plasma fluctuations that exist there. There are four special scales that separate physically distinct regimes: the electron and ion gyroscales, the mean free path and the electron diffusion scale. In each of the scale ranges separated …
Date:
April 23, 2009
Creator:
A.A. Schekochihin, S.C. Cowley, W. Dorland, G.W. Hammett, G.G. Howes, E. Quataert, and T. Tatsuno
Object Type:
Report
System:
The UNT Digital Library
Simulation of a Production Facility with an Automated Transport System
A model was needed to assess material throughput and validate the conceptual design of a production facility, including equipment lists and layout. The initial desire was to use a commercially available discrete event simulation package. However, the available software was found to be too limited in capability. Database interface software was used to develop autonomous intelligent manufacturing workstations and material transporters. The initial Extend model used to assess material throughput and develop equipment lists for the preconceptual design effort was upgraded with software add-ons from Simulation Dynamics, Inc. (SDI). Use of the SDI database interface allowed the upgraded model to include: 1. a material mass balance at any level of detail required by the user, and 2. a transport system model that includes all transport system movements, time delays, and transfers between systems. This model will assist in evaluating transport system capacity, sensitive time delays in the system, and optimal operating strategies. An additional benefit of using the SDI database interface is dramatically improved run time performance. This allows significantly more runs to be completed to provide better statistics for overall plant performance. The model has all system and process parameters entered into sub-component accessible tables. All information for the …
Date:
April 7, 2004
Creator:
ABRAMCZYK, GLENN
Object Type:
Report
System:
The UNT Digital Library
EFFECTS OF XE ION IRRADIATION AND SUBSEQUENT ANNEALING ON THE PROPERTIES OF MAGNESIUM-ALUMINATE SPINEL
Single crystals of magnesium-aluminate spinel MgAl{sub 2}O{sub 4} were irradiated with 340 keV Xe{sup 2} ions at {minus}173 C ({approximately} 100 K). A fluence of 1 x 10{sup 20} Xe/m{sup 2} created an amorphous layer at the surface of the samples. The samples were annealed for 1 h at different temperatures ranging from 130 C to 880 C. Recrystallization took place in the temperature interval between 610 C and 855 C. Transmission electron microscopy (TEM) images show two distinct layers near the surface: (1) a polycrystalline layer with columnar grain structure; and (2) a buried damaged layer epitaxial with the substrate. After annealing at 1100 C for 52 days, the profile of implanted Xe ions did not change, which means that Xe ions are not mobile in the spinel structure up to 1100 C. The thickness of the buried damaged layer decreased significantly in the 1100 C annealed sample comparing to the sample annealed for 1 h at 855 C.
Date:
April 1, 2000
Creator:
AFANASYEV, I. & AL, ET
Object Type:
Article
System:
The UNT Digital Library
Evaluation of the Cask Transportation Facility Modifications (CTFM) compliance to DOE order 6430.1A Project A.5 and A.6
This report was prepared to evaluate the compliance of CTFM to DOE Order 6430.1A. This document presents the results of an evaluation that was performed to assess compliance of the K West (KW) Cask Transportation Facility Modifications (CTFM) designs against applicable requirements of Department of Energy (DOE) Order 6430.1 A, General Design Criteria. This evaluation was grouped under two categories described as Cask Loadout System (CLS) and Cranes/Other Modifications.
Date:
April 24, 2000
Creator:
ARD, K.E.
Object Type:
Report
System:
The UNT Digital Library
Spent Nuclear Fuel (SNF) Project Cask and MCO Helium Purge System Design Review Completion Report Project A.5 and A.6
This report documents the results of the design verification performed on the Cask and Multiple Canister Over-pack (MCO) Helium Purge System. The helium purge system is part of the Spent Nuclear Fuel (SNF) Project Cask Loadout System (CLS) at 100K area. The design verification employed the ''Independent Review Method'' in accordance with Administrative Procedure (AP) EN-6-027-01.
Date:
April 19, 2000
Creator:
ARD, K.E.
Object Type:
Report
System:
The UNT Digital Library
FUTURE PLANS AT BNL: RHIC-II AND eRHIC.
The development of future facilities relevant to the study of deep inelastic scattering at BNL is described.
Date:
April 16, 2007
Creator:
ARONSON,S.
Object Type:
Article
System:
The UNT Digital Library
Volatile organic compounds in indoor air: A review ofconcentrations measured in North America since 1990
Central tendency and upper limit concentrations of volatile organic compounds (VOCs) measured in indoor air are summarized and reviewed. Data were obtained from published cross-sectional studies of residential and office buildings conducted in North America from 1990through the present. VOC concentrations in existing residences reported in 12 studies comprise the majority of the data set. Central tendency and maximum concentrations are compared between new and existing residences and between existing residences and office buildings. Historical changes in indoor VOC concentrations since the Clean Air Act Amendments of 1990 are explored by comparing the current data set with two published reviews of previous data obtained primarily in the 1980s. These historical comparisons suggest average indoor concentrations of some toxic air contaminants, such as 1,1,1-trichloroethane have decreased.
Date:
April 1, 2003
Creator:
ATHodgson@lbl.gov
Object Type:
Report
System:
The UNT Digital Library
Hydrogen Storage Properties of Magnesium Base Nanostructured Composite Materials
In this work, nanostructured composite materials have been synthesized using the mechanical alloying process. The new materials produced have been investigated by X-ray diffraction (XRD), transition electron microscope (TEM), scanning electron microscope (SEM) and electron energy dispersion spectrum (EDS) for their phase compositions, crystal structure, grain size, particle morphology and the distribution of catalyst element. Hydrogen storage capacities and the hydriding-dehydriding kinetics of the new materials have been measured at different temperatures using a Sieverts apparatus. It is observed that mechanical alloying accelerates the hydrogenation kinetics of the magnesium based materials at low temperature, but a high temperature must be provided to release the absorbed hydrogen from the hydrided magnesium based materials. It is believed that the dehydriding temperature is largely controlled by the thermodynamic configuration of magnesium hydride. Doping Mg-Ni nano/amorphous composite materials with lanthanum reduces the hydriding and dehydriding temperature. Although the stability of MgH2 can not be easily reduced by ball milling alone, the results suggest the thermodynamic properties of Mg-Ni nano/amorphous composite materials can be alternated by additives such as La or other effective elements. Further investigation toward understanding the mechanism of additives will be rewarded.
Date:
April 30, 2004
Creator:
AU, M
Object Type:
Article
System:
The UNT Digital Library
Laser Hazard Analysis for Ultra-Fast Sub-Nanosecond, Mode-Locked Near Infrared Lasers Operated with Pulse Repetition Frequencies Above the Critical Frequency
Ultra fast, sub-nanosecond (picosecond to femtosecond) duration, laser pulses present unique challenges when performing laser safety analysis involving mode-locked lasers, which operate at pulse repetition frequencies above the critical frequency in the near infrared wavelength bands. Two specific cases are presented, one such case that agrees and one that disagrees with the general rule on critical frequency. The results show that in all cases the appropriate maximum permissible exposure is always the smallest of the values calculated from ANSI rule 1, 2 and 3.
Date:
April 1, 2003
Creator:
AUGUSTONI, ARNOLD L.
Object Type:
Report
System:
The UNT Digital Library
Power Technologies Energy Data Book - Third Edition
This report, prepared by NREL's Energy Analysis Office, includes up-to-date information on power technologies, including complete technology profiles. The data book also contains charts on electricity restructuring, power technology forecasts, electricity supply, electricity capability, electricity generation, electricity demand, prices, economic indicators, environmental indicators, and conversion factors.
Date:
April 1, 2005
Creator:
Aabakken, J.
Object Type:
Report
System:
The UNT Digital Library
Search for Heavy, Long-Lived Neutralinos that Decay to Photons at CDF II Using Photon Timing
The authors present the results of the first hadron collider search for heavy, long-lived neutralinos that decay via {tilde {chi}}{sub 1}{sup 0} {yields} {gamma}{tilde G} in gauge-mediated supersymmetry breaking models. Using an integrated luminosity of 570 {+-} 34 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, they select {gamma}+jet+missing transverse energy candidate events based on the arrival time of a high-energy photon at the electromagnetic calorimeter as measured with a timing system that was recently installed on the CDF II detector. They find 2 events, consistent with the background estimate of 1.3 {+-} 0.7 events. While the search strategy does not rely on model-specific dynamics, they set cross section limits and place the world-best 95% C.L. lower limit on the {tilde {chi}}{sub 1}{sup 0} mass of 101 GeV/c{sup 2} at {tau}{sub {tilde {chi}}{sub 1}{sup 0}} = 5 ns.
Date:
April 1, 2008
Creator:
Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of Particle Production and Inclusive Differential Cross Sections in p anti-p Collisions at s**(1/2) = 1.96-TeV
We report a set of measurements of particle production in inelastic p{bar p} collisions collected with a minimum-bias trigger at the Tevatron Collider with the CDF II experiment. The inclusive charged particle transverse momentum differential cross section is measured, with improved precision, over a range about ten times wider than in previous measurements. The former modeling of the spectrum appears to be incompatible with the high particle momenta observed. The dependence of the charged particle transverse momentum on the event particle multiplicity is analyzed to study the various components of hadron interactions. This is one of the observable variables most poorly reproduced by the available Monte Carlo generators. A first measurement of the event transverse energy sum differential cross section is also reported. A comparison with a PYTHIA prediction at the hadron level is performed. The inclusive charged particle differential production cross section is fairly well reproduced only in the transverse momentum range available from previous measurements. At higher momentum the agreement is poor. The transverse energy sum is poorly reproduced over the whole spectrum. The dependence of the charged particle transverse momentum on the particle multiplicity needs the introduction of more sophisticated particle production mechanisms, such as multiple parton …
Date:
April 1, 2009
Creator:
Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for the Rare Decays B^+ -> mu^+ mu^- K^+, B^0 -> mu^+ mu^- K^*0(892), and B^0_s -> mu^+ mu^- phi at CDF
The authors search for b {yields} s{mu}{sup +}{mu}{sup -} transitions in B meson (B{sup +}, B{sup 0}, or B{sub s}{sup 0}) decays with 924 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. They find excesses with significances of 4.5, 2.9, and 2.4 standard deviations in the B{sup +} {yields} {mu}{sup +}{mu}{sup -}K{sup +}, B{sup 0} {yields} {mu}{sup +}{mu}{sup -}K*(892){sup 0}, and B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -}{phi} decay modes, respectively. Using B {yields} J/{psi}h (h - K{sup +}, K*(892){sup 0}, {phi}) decays as normalization channels, they report branching fractions for the previously observed B{sup +} and B{sup 0} decays as normalization channels, they report branching fractions for the previously observed B{sup +} and B{sup 0} decays, {Beta}(B{sup +} {yields} {mu}{sup +}{mu}{sup -}K{sup +}) = (0.59 {+-} 0.15 {+-} 0.04) x 10{sup -6}, and {Beta}(B{sup 0} {yields} {mu}{sup +}{mu}{sup -}K*(892){sup 0}) = (0.81 {+-} 0.30 {+-} 0.10) x 10{sup -6}, where the first uncertainty is statistical, and the second is systematic. These measurements are consistent with the world average results, and are competitive with the best available measurements. They set an upper limit on the relative branching …
Date:
April 1, 2008
Creator:
Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Object Type:
Article
System:
The UNT Digital Library
Search for CP violation in semileptonic B(s)0 decays
We have performed a search for CP violation in a sample of semileptonic B{sub s}{sup 0} decays corresponding to approximately 5 fb{sup -1} of data collected by the D0 detector in Run II at the Fermilab Tevatron Collider. A time-dependent fit to the distributions of the B{sub s}{sup 0} candidates yields the flavor-specific asymmetry a{sub fs}{sup s} = [-1.7 {+-} 9.1(stat){sub -2.3}{sup +1.2}(syst)] x 10{sup -3}. This is the most precise measurement to date of this CP violation parameter.
Date:
April 1, 2009
Creator:
Abazov, : V.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the forward-backward charge asymmetry and extraction of $sin^2Theta^{eff}_W$ in $p\bar{p} \to Z/\gamma^{*}+X \to e^+e^-+X$ events produced at $\sqrt{s}=1.96$ TeV
We present a measurement of the forward-backward charge asymmetry (A{sub FB}) in p{bar p} {yields} Z/{gamma}* + X {yields} e{sup +}e{sup -} + X events at a center-of-mass energy of 1.96 TeV using 1.1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider. A{sub FB} is measured as a function of the invariant mass of the electron-positron pair, and found to be consistent with the standard model prediction. We use the A{sub FB} measurement to extract the effective weak mixing angle sin{sup 2} {theta}{sub W}{sup eff} = 0.2327 {+-} 0.0018 (stat.) {+-} 0.0006 (syst.).
Date:
April 1, 2008
Creator:
Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the Lambda(b) lifetime in the exclusive decay Lambda(b) ---> J / psi Lambda
We have measured the {lambda}{sub b} lifetime using the exclusive decay {lambda}{sub b}{yields}J/{psi}{lambda}, based on 1.2 fb{sup -1} of data collected with the D0 detector during 2002-2006. From 171 reconstructed {lambda}{sub b} decays, where the J/{psi} and {lambda} are identified via the decays J/{psi}{yields}{mu}{sup +}{mu}{sup -} and {lambda}{yields}p{pi}, we measured the {lambda}{sub b} lifetime to be {tau}({lambda}{sub b})=1.218{sub -0.115}{sup +0.130}(stat){+-}0.042(syst) ps. We also measured the B{sup 0} lifetime in the decay B{sup 0}{yields}J/{psi}({mu}{sup +}{mu}{sup -})K{sub S}{sup 0}({pi}{sup +}{pi}{sup -}) to be {tau}(B{sup 0})=1.501{sub -0.074}{sup +0.078}(stat){+-}0.050(syst) ps, yielding a lifetime ratio of {tau}({lambda}{sub b})/{tau}(B{sup 0})=0.811{sub -0.087}{sup +0.096}(stat){+-}0.034(syst = )
Date:
April 1, 2007
Creator:
Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the polarization of the $\Upsilon(1S)$ and $\Upsilon(2S)$ states in $p\bar{p}$ collisions at $\sqrt{s}=$1.96 TeV
We present a study of the polarization of the {Upsilon}(1S) and {Upsilon}(2S) states using a 1.3 fb{sup -1} data sample collected by the D0 experiment in 2002-2006 during Run II of the Fermilab Tevatron Collider. We measure the polarization parameter {alpha} = ({sigma}{sub T} - 2{sigma}{sub L})/({sigma}{sub T} + 2{sigma}{sub L}), where {sigma}{sub T} and {sigma}{sub L} are the transversely and longitudinally polarized components of the production cross section, as a function of the transverse momentum (p{sub T}{sup {Upsilon}}) for the {Upsilon}(1S) and {Upsilon}(2S). Significant p{sub T}{sup {Upsilon}}-dependent longitudinal polarization is observed for the {Upsilon}(1S). A comparison with theoretical models is presented.
Date:
April 1, 2008
Creator:
Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type:
Article
System:
The UNT Digital Library