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Corrective Action Investigation Plan for Corrective Action Unit 143: Area 25 Contaminated Waste Dumps, Nevada Test Site, Nevada (open access)

Corrective Action Investigation Plan for Corrective Action Unit 143: Area 25 Contaminated Waste Dumps, Nevada Test Site, Nevada

None
Date: July 12, 1999
Creator: /NV, USDOE
Object Type: Report
System: The UNT Digital Library
Raising Photoemission Efficiency with Surface Acoustic Waves (open access)

Raising Photoemission Efficiency with Surface Acoustic Waves

We are developing a novel technique that may help increase the efficiency and reduce costs of photoelectron sources used at electron accelerators. The technique is based on the use of Surface Acoustic Waves (SAW) in piezoelectric materials, such as GaAs, that are commonly used as photocathodes. Piezoelectric fields produced by the traveling SAW spatially separate electrons and holes, reducing their probability of recombination, thereby enhancing the photoemission quantum efficiency of the photocathode. Additional advantages could be increased polarization provided by the enhanced mobility of charge carriers that can be controlled by the SAW and the ionization of optically-generated excitons resulting in the creation of additional electron-hole pairs. It is expected that these novel features will reduce the cost of accelerator operation. A theoretical model for photoemission in the presence of SAW has been developed, and experimental tests of the technique are underway.
Date: July 1, 2012
Creator: A. Afanasev, F. Hassani, C.E. Korman, V.G. Dudnikov, R.P. Johnson, M. Poelker, K.E.L. Surles-Law
Object Type: Article
System: The UNT Digital Library
Effects of Global Boundary and Local Collisionality on Magnetic Reconnection in a Laboratory Plasma (open access)

Effects of Global Boundary and Local Collisionality on Magnetic Reconnection in a Laboratory Plasma

The magnetic reconnection process is studied in a wide range of operating conditions in the well-controlled Magnetic Reconnection Experiment. The reconnection rate is observed to be a function of both global (i.e., system size) and local (collisionality) plasma parameters. When only local collisionality is lowered, the current sheet is shortened while effective resistivity is enhanced, both accelerating reconnection rates. At a fixed collisionality, the current sheet length increases with system size, resulting in the reduction of the reconnection rate. These results quantitatively agree with a generalized Sweet-Parker analysis.
Date: July 24, 2007
Creator: A. Kuritsyn, H. Ji, S.P. Gerhardt, Y. Ren, and M. Yamada
Object Type: Report
System: The UNT Digital Library
Intra-beam scattering and its applications to ERL (open access)

Intra-beam scattering and its applications to ERL

N/A
Date: July 1, 2012
Creator: A., Fedotov
Object Type: Report
System: The UNT Digital Library
Potential for Luminosity improvement for low-energy RHIC operations with long bunches (open access)

Potential for Luminosity improvement for low-energy RHIC operations with long bunches

N/A
Date: July 1, 2012
Creator: A., Fedotov & Blaskiewicz, M.
Object Type: Report
System: The UNT Digital Library
Part II/Addendum Electron Beam Cooling between EBIS LINAC and Booster; Is Single Pass Cooling Possible? (open access)

Part II/Addendum Electron Beam Cooling between EBIS LINAC and Booster; Is Single Pass Cooling Possible?

N/A
Date: July 1, 2008
Creator: A., Hershcovitch
Object Type: Report
System: The UNT Digital Library
Thermal characteristics of air flow cooling in the lithium ion batteries experimental chamber (open access)

Thermal characteristics of air flow cooling in the lithium ion batteries experimental chamber

A battery pack prototype has been designed and built to evaluate various air cooling concepts for the thermal management of Li-ion batteries. The heat generation from the Li-Ion batteries was simulated with electrical heat generation devices with the same dimensions as the Li-Ion battery (200 mm x 150 mm x 12 mm). Each battery simulator generates up to 15W of heat. There are 20 temperature probes placed uniformly on the surface of the battery simulator, which can measure temperatures in the range from -40 C to +120 C. The prototype for the pack has up to 100 battery simulators and temperature probes are recorder using a PC based DAQ system. We can measure the average surface temperature of the simulator, temperature distribution on each surface and temperature distributions in the pack. The pack which holds the battery simulators is built as a crate, with adjustable gap (varies from 2mm to 5mm) between the simulators for air flow channel studies. The total system flow rate and the inlet flow temperature are controlled during the test. The cooling channel with various heat transfer enhancing devices can be installed between the simulators to investigate the cooling performance. The prototype was designed to configure …
Date: July 8, 2012
Creator: A., Lukhanin; U., Rohatgi; Belyaev, A.; Fedorchenko, D.; Khazhmuradov, M.; Lukhanin, O et al.
Object Type: Article
System: The UNT Digital Library
Electron Gun for RHIC EBIS (open access)

Electron Gun for RHIC EBIS

N/A
Date: July 1, 2006
Creator: A., Pikin
Object Type: Report
System: The UNT Digital Library
Optical, Thermal and Stress Simulations of a 300-kwatt Electron Collector (open access)

Optical, Thermal and Stress Simulations of a 300-kwatt Electron Collector

N/A
Date: July 1, 2006
Creator: A., Pikin; Kponou, A. & Snydstrup, L.
Object Type: Report
System: The UNT Digital Library
Frequency budget for the PoP cavity (open access)

Frequency budget for the PoP cavity

None
Date: July 1, 1995
Creator: A., Ratti
Object Type: Report
System: The UNT Digital Library
Longitudinal coupling impedance measurements of a bellow at low frequencies (open access)

Longitudinal coupling impedance measurements of a bellow at low frequencies

None
Date: July 1, 1993
Creator: A., Ratti
Object Type: Report
System: The UNT Digital Library
F(1) for B (forward) D*ln from lattice QCD (open access)

F(1) for B (forward) D*ln from lattice QCD

The authors would like to determine |V{sub cb}| from the exclusive semi-leptonic decay B{yields}D*lv. The differential decay rate is d{Lambda}/dw = G{sub F}{sup 2}/4{pi}{sup 3}(w{sup 2}-1){sup 1/2}m{sub D*}{sup 3} (m{sub B}-m{sub D*}){sup 2}G(w)|V{sub cb}|{sup 2}|F{sub B{yields}D*}(w)|{sup 2}, where w = v {center_dot} v{prime} and G(1) = 1. At zero recoil (w = 1) heavy-quark symmetry requires F{sub B{yields}D*}(1) to be close to 1. So, |V{sub cb}| is determined by dividing measurements of d{Lambda}/dw by the phase space and well-known factors, and extrapolating to w {yields} 1. This yields |V{sub cb}|F{sub B{yields}D*}(1), and F{sub B{yields}D*}(1) is taken from ''theory''. To date models [1] or a combination of a rigorous inequality plus judgement [2] have been used to estimate F{sub B{yields}D*}(1) - 1. In this work [3] they calculate F{sub B{yields}D*}(1) with lattice gauge theory, in the so-called quenched approximation, but the uncertainty from quenching is included in the error budget.
Date: July 12, 2002
Creator: A.S. Kronfeld, P.B. Mackenzie and J.N. Simone
Object Type: Article
System: The UNT Digital Library
Design of a Precast Concrete Stay-in-Place Forming System for Lock Wall Rehabilitation (open access)

Design of a Precast Concrete Stay-in-Place Forming System for Lock Wall Rehabilitation

Report describing the design of forming a system to use pre-cast concrete for rehabilitating damaged walls in locks, as a way to prevent problems with cracking in replacement air-entrained concrete used in standard methods.
Date: July 1987
Creator: ABAM Engineers Incorporated
Object Type: Report
System: The UNT Digital Library
Chemometric Analysis of Nuclear Magnetic Resonance Spectroscopy Data (open access)

Chemometric Analysis of Nuclear Magnetic Resonance Spectroscopy Data

Chemometric analysis of nuclear magnetic resonance (NMR) spectroscopy has increased dramatically in recent years. A variety of different chemometric techniques have been applied to a wide range of problems in food, agricultural, medical, process and industrial systems. This article gives a brief review of chemometric analysis of NMR spectral data, including a summary of the types of mixtures and experiments analyzed with chemometric techniques. Common experimental problems encountered during the chemometric analysis of NMR data are also discussed.
Date: July 20, 2000
Creator: ALAM,TODD M. & ALAM,M. KATHLEEN
Object Type: Article
System: The UNT Digital Library
Acoustic Wave Equations for a Linear Viscous Fluid and An Ideal Fluid (open access)

Acoustic Wave Equations for a Linear Viscous Fluid and An Ideal Fluid

The mathematical description of acoustic wave propagation within a time- and space-varying, and moving, linear viscous fluid is formulated as a system of coupled linear equations. This system is rigorously developed from fundamental principles of continuum mechanics (conservation of mass, balance of linear and angular momentum, balance of entropy) and various constitutive relations (for stress, entropy production, and entropy conduction) by linearizing all expressions with respect to the small-amplitude acoustic wavefield variables. A significant simplification arises if the fluid medium is neither viscous nor heat conducting (i.e., an ideal fluid). In this case the mathematical system can be reduced to a set of five, coupled, first-order partial differential equations. Coefficients in the systems depend on various mechanical and thermodynamic properties of the ambient medium that supports acoustic wave propagation. These material properties cannot all be arbitrarily specified, but must satisfy another system of nonlinear expressions characterizing the dynamic behavior of the background medium. Dramatic simplifications in both systems occur if the ambient medium is simultaneously adiabatic and stationary.
Date: July 1, 2002
Creator: ALDRIDGE, DAVID F.
Object Type: Report
System: The UNT Digital Library
Elastic Wave Radiation from a Pressurized Spherical Cavity (open access)

Elastic Wave Radiation from a Pressurized Spherical Cavity

None
Date: July 1, 2002
Creator: ALDRIDGE, DAVID F.
Object Type: Report
System: The UNT Digital Library
Fast Grid Search Algorithm for Seismic Source Location (open access)

Fast Grid Search Algorithm for Seismic Source Location

The spatial and temporal origin of a seismic energy source are estimated with a first grid search technique. This approach has greater likelihood of finding the global rninirnum of the arrival time misiit function compared with conventional linearized iterative methods. Assumption of a homogeneous and isotropic seismic velocity model allows for extremely rapid computation of predicted arrival times, but probably limits application of the method to certain geologic environments and/or recording geometries. Contour plots of the arrival time misfit function in the vicinity of the global minimum are extremely useful for (i) quantizing the uncertainty of an estimated hypocenter solution and (ii) analyzing the resolving power of a given recording configuration. In particular, simultaneous inversion of both P-wave and S-wave arrival times appears to yield a superior solution in the sense of being more precisely localized in space and time. Future research with this algorithm may involve (i) investigating the utility of nonuniform residual weighting schemes, (ii) incorporating linear and/or layered velocity models into the calculation of predicted arrival times, and (iii) applying it toward rational design of microseismic monitoring networks.
Date: July 1, 2000
Creator: ALDRIDGE,DAVID F.
Object Type: Report
System: The UNT Digital Library
AN APPROACH TO EXTREME-SCALE SIMULATION OF NOVEL ARCHITECTURES (open access)

AN APPROACH TO EXTREME-SCALE SIMULATION OF NOVEL ARCHITECTURES

None
Date: July 1, 2001
Creator: ALEXANDER, F. J.; BERKBIGLER, K. & AL, ET
Object Type: Article
System: The UNT Digital Library
Frequency Doubling Broadband Light in Multiple Crystals (open access)

Frequency Doubling Broadband Light in Multiple Crystals

The authors compare frequency doubling of broadband light in a single nonlinear crystal with doubling in five crystals with intercrystal temporal walk off compensation, and with doubling in five crystals adjusted for offset phase matching frequencies. Using a plane-wave, dispersive numerical model of frequency doubling they study the bandwidth of the second harmonic and the conversion efficiency as functions of crystal length and fundamental irradiance. For low irradiance the offset phase matching arrangement has lower efficiency than a single crystal of the same total length but gives a broader second harmonic bandwidth. The walk off compensated arrangement gives both higher conversion efficiency and broader bandwidth than a single crystal. At high irradiance, both multicrystal arrangements improve on the single crystal efficiency while maintaining broad bandwidth.
Date: July 26, 2000
Creator: ALFORD,WILLIAM J. & SMITH,ARLEE V.
Object Type: Article
System: The UNT Digital Library
Wavelength Variation of the Second-Order Nonlinear Coefficients of KNbO3, KTiOPO4, KTiOAsO4, LiNbO3, LiIO3, B-BaB2O4, KH2PO4, and LiB3O5 Crystals: A Test of Miller Wavelength Scaling (open access)
Cooperative Monitoring Center Occasional Paper/16: The Potential of Technology for the Control of Small Weapons: Applications in Developing Countries (open access)

Cooperative Monitoring Center Occasional Paper/16: The Potential of Technology for the Control of Small Weapons: Applications in Developing Countries

For improving the control of small arms, technology provides many possibilities. Present and future technical means are described in several areas. With the help of sensors deployed on the ground or on board aircraft, larger areas can be monitored. Using tags, seals, and locks, important objects and installations can be safeguarded better. With modern data processing and communication systems, more information can be available, and it can be more speedily processed. Together with navigation and transport equipment, action can be taken faster and at greater range. Particular considerations are presented for cargo control at roads, seaports, and airports, for monitoring designated lines, and for the control of legal arms. By starting at a modest level, costs can be kept low, which would aid developing countries. From the menu of technologies available, systems need to be designed for the intended application and with an understanding of the local conditions. It is recommended that states start with short-term steps, such as acquiring more and better radio transceivers, vehicles, small aircraft, and personal computers. For the medium term, states should begin with experiments and field testing of technologies such as tags, sensors, and digital communication equipment.
Date: July 1, 2000
Creator: ALTMANN, JURGEN
Object Type: Report
System: The UNT Digital Library
Land-Based Geologic Emplacement of Mercury Wastes (open access)

Land-Based Geologic Emplacement of Mercury Wastes

None
Date: July 20, 2000
Creator: ANDERSON,D. RICHARD
Object Type: Article
System: The UNT Digital Library
Evaluation of the Cask Transportation Facility Modifications (CTFM) compliance to DOE order 6430.1A (open access)

Evaluation of the Cask Transportation Facility Modifications (CTFM) compliance to DOE order 6430.1A

This report was prepared to evaluate the compliance of Cask Transportation Facility Modifications (CTFM) to DOE Order 6430.1A.
Date: July 14, 1999
Creator: ARD, K.E.
Object Type: Report
System: The UNT Digital Library
THE PHENIX EXPERIMENT AT RHIC. (open access)

THE PHENIX EXPERIMENT AT RHIC.

PHENIX is a large detector at the Relativistic Heavy Ion Collider (RHIC) at BNL. RHIC and PHENIX have recently operated for the first time, producing and detecting collisions of gold ions at beam energies of 30 and 65 GeV per nucleon. The current performance and future plans of PHENIX and of RHIC are presented.
Date: July 27, 2000
Creator: ARONSON,S. FOR THE PHENIX COLLABORATION
Object Type: Article
System: The UNT Digital Library