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Space-charge compensation in high-intensity proton rings

Description: Recently, it was proposed to use negatively charged electron beams for compensation of beam-beam effects due to protons in the Tevatron collider. The authors show that a similar compensation is possible in space-charge dominated low energy proton beams. The idea has a potential of several-fold increase of the FNAL Booster beam brightness. Best results will be obtained using three electron lenses around the machine circumference, using co-moving electron beam with time structure and profile appr… more
Date: September 21, 2000
Creator: A. Burov, G.W. Foster and V.D. Shiltsev
open access

CATALYSIS SCIENCE AND TECHNOLOGY

Description: This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Our objectives were to develop a multidisciplinary team and capabilities to develop a fundamental understanding of homogeneous, heterogeneous, and heterogenized catalysts. With the aid of theoretical chemistry approaches we explored and characterized the chemical reactivity and physical properties of a large number of catalytic systems.
Date: August 1, 2000
Creator: ABRAMS, M.; BAKER, R. & AL, ET
open access

EFFECTS OF XE ION IRRADIATION AND SUBSEQUENT ANNEALING ON THE PROPERTIES OF MAGNESIUM-ALUMINATE SPINEL

Description: 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… more
Date: April 1, 2000
Creator: AFANASYEV, I. & AL, ET
open access

High performance anti-reflection coatings for broadband multi-junction solar cells

Description: The success of bandgap engineering has made high efficiency broadband multi-junction solar cells possible with photo-response out to the band edge of Ge. Modeling has been conducted which suggests that current double layer anti-reflection coating technology is not adequate for these devices in certain cases. Approaches for the development of higher performance anti-reflection coatings are examined. A new AR coating structure based on the use of Herpin equivalent layers is presented. Optical mod… more
Date: February 23, 2000
Creator: AIKEN,DANIEL J.
open access

Spectroscopic Detection of Pathogens

Description: The goal of this LDRD Research project was to provide a preliminary examination of the use of infrared spectroscopy as a tool to detect the changes in cell cultures upon activation by an infectious agent. Due to a late arrival of funding, only 5 months were available to transfer and setup equipment at UTTM,develop cell culture lines, test methods of in-situ activation and collect kinetic data from activated cells. Using attenuated total reflectance (ATR) as a sampling method, live cell cultures… more
Date: November 1, 2000
Creator: ALAM,M. KATHLEEN; TIMLIN,JERILYN A.; MARTIN,LAURA E.; HJELLE,DRIAN; LYONS,RICK & GARRISON,KRISTIN
open access

Molecular dynamic simulations, {sup 6}Li solid state NMR and ultraphosphate glasses

Description: The author's laboratory continues to use NMR to investigate the structure and dynamics in amorphous materials, including the local structure of ultraphosphate glasses. Changes in the alkali environment in these phosphate glasses as a function of modifier concentration has recently been probed using {sup 6}Li and {sup 23}Na solid state NMR. Molecular dynamic (MD) simulations have also been performed in an attempt to gain additional insight into the variations of the local structure. Interestingl… more
Date: May 1, 2000
Creator: ALAM,TODD M.
open access

Monte Carlo simulations of phosphate polyhedron connectivity in glasses

Description: Monte Carlo simulations of phosphate tetrahedron connectivity distributions in alkali and alkaline earth phosphate glasses are reported. By utilizing a discrete bond model, the distribution of next-nearest neighbor connectivities between phosphate polyhedron for random, alternating and clustering bonding scenarios was evaluated as a function of the relative bond energy difference. The simulated distributions are compared to experimentally observed connectivities reported for solid-state two-dim… more
Date: January 1, 2000
Creator: ALAM,TODD M.
open access

Chemometric Analysis of Nuclear Magnetic Resonance Spectroscopy Data

Description: 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 th… more
Date: July 20, 2000
Creator: ALAM,TODD M. & ALAM,M. KATHLEEN
open access

MICROHOLE TECHNOLOGY PROGRESS ON BOREHOLE INSTRUMENTATION DEVELOPMENT

Description: Microhole technology development is based on the premise that with advances in electronics and sensors, large conventional-diameter wells are no longer necessary for obtaining subsurface information. Furthermore, microholes offer an environment for improved substance measurement. The combination of deep microholes having diameters of 1-3/8 in. at their terminal depth and 7/8-in. diameter logging tools will comprise a very low cost alternative to currently available technology for deep subsurfac… more
Date: September 1, 2000
Creator: ALBRIGHT, J.
open access

Accident and Off Normal Response and Recovery from Multi Canister Overpack (MCO) Processing Events

Description: In the process of removing spent nuclear fuel (SNF) from the K Basins through its subsequent packaging, drymg, transportation and storage steps, the SNF Project must be able to respond to all anticipated or foreseeable off-normal and accident events that may occur. Response procedures and recovery plans need to be in place, personnel training established and implemented to ensure the project will be capable of appropriate actions. To establish suitable project planning, these events must first … more
Date: September 19, 2000
Creator: ALDERMAN, C.A.
open access

Fast Grid Search Algorithm for Seismic Source Location

Description: 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 … more
Date: July 1, 2000
Creator: ALDRIDGE,DAVID F.
open access

Frequency Doubling Broadband Light in Multiple Crystals

Description: 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 match… more
Date: July 26, 2000
Creator: ALFORD,WILLIAM J. & SMITH,ARLEE V.
open access

INVESTIGATION OF HALO FORMATION IN CONTINUOUS BEAMS USING WEIGHTED POLYNOMIAL EXPANSIONS AND PERTURBATIONAL ANALYSIS

Description: We consider halo formation in continuous beams oscillating at natural modes by inspecting particle trajectories. Trajectory equations containing field nonlinearities are derived from a weighted polynomial expansion. We then use perturbational techniques to further analyze particle motion.
Date: August 1, 2000
Creator: ALLEN, C.
open access

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

Description: 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… more
Date: July 1, 2000
Creator: ALTMANN, JURGEN
open access

Methodology for characterizing modeling and discretization uncertainties in computational simulation

Description: This research effort focuses on methodology for quantifying the effects of model uncertainty and discretization error on computational modeling and simulation. The work is directed towards developing methodologies which treat model form assumptions within an overall framework for uncertainty quantification, for the purpose of developing estimates of total prediction uncertainty. The present effort consists of work in three areas: framework development for sources of uncertainty and error in the… more
Date: March 1, 2000
Creator: ALVIN,KENNETH F.; OBERKAMPF,WILLIAM L.; RUTHERFORD,BRIAN M. & DIEGERT,KATHLEEN V.
open access

Use of inelastic analysis in cask design

Description: In this paper, the advantages and disadvantages of inelastic analysis are discussed. Example calculations and designs showing the implications and significance of factors affecting inelastic analysis are given. From the results described in this paper it can be seen that inelastic analysis provides an improved method for the design of casks. It can also be seen that additional code and standards work is needed to give designers guidance in the use of inelastic analysis. Development of these cod… more
Date: May 15, 2000
Creator: AMMERMAN,DOUGLAS J. & BREIVIK,NICOLE L.
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