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Transition energy correlations in the three-body continuum of Borromean halo nuclei

Description: Energy correlations in transitions from the bound state to the three-body continuum of Borromean halo nuclei are considered. A core+n+n three-body cluster model which reproduces experimentally known properties of {sup 6}He and {sup 11}Li has been used to study low-lying resonances and soft modes. The analysis of the correlated responses in {sup 6}He shows that in the case of the narrow three-body 2{sub 1}{sup +} resonance the transition energy correlations are the same as in the intrinsic corre… more
Date: June 5, 2007
Creator: Danilin, B V; Vaagen, J S; Rogde, T; Ershov, S N; Thompson, I J & Zhukov, M V
Partner: UNT Libraries Government Documents Department
open access

The Emma Commissioning Procedure

Description: The author begins with a brief review of the goals of the EMMA experiment. He then describe two stages of EMMA commissioning. The first stage is simply to get the beam to circulate a full turn in the ring, and is done only once during the course of the experiment. The second stage will be repeated several times, at least once for each lattice configuration, and involves two parts: setting the required values for the machine parameters, and determining the tunes and time of flight as a function … more
Date: November 5, 2007
Creator: Berg, J. S.
Partner: UNT Libraries Government Documents Department
open access

Non-destructive Identification of Individual Leukemia Cells by Optical Trapping Raman Spectroscopy

Description: Currently, a combination of technologies is typically required to assess the malignancy of cancer cells. These methods often lack the specificity and sensitivity necessary for early, accurate diagnosis. Here we demonstrate using clinical samples the application of laser trapping Raman spectroscopy as a novel approach that provides intrinsic biochemical markers for the noninvasive detection of individual cancer cells. The Raman spectra of live, hematopoietic cells provide reliable molecular fing… more
Date: March 5, 2007
Creator: Chan, J W; Taylor, D S; Lane, S; Zwerdling, T; Tuscano, J & Huser, T
Partner: UNT Libraries Government Documents Department
open access

Overview of the National Atmospheric Release Advisory Center's urban research and development activities

Description: This presentation describes the tools and services provided by the National Atmospheric Release Advisory Center (NARAC) at Lawrence Livermore National Laboratory (LLNL) for modeling the impacts of airborne hazardous materials. NARAC provides atmospheric plume modeling tools and services for chemical, biological, radiological, and nuclear airborne hazards. NARAC can simulate downwind effects from a variety of scenarios, including fires, industrial and transportation accidents, radiation dispersa… more
Date: September 5, 2007
Creator: Lundquist, J K; Sugiyama, G A & Nasstrom, J
Partner: UNT Libraries Government Documents Department
open access

High-Resolution Spectroscopy of K-shell Praseodymium with a High-Energy Calorimeter

Description: We present a measurement of the K-shell spectrum of He-like through Be-like praseodymium ions trapped in the Livermore SuperEBIT electron beam ion trap using a bismuth absorber pixel on the XRS/EBIT microcalorimeter. This measurement is the first of its kind where the n=2 to n=1 transitions of the various charge states are spectroscopically resolved. The measured transition energies are compared with theoretical calculations from several atomic codes.
Date: June 5, 2007
Creator: Thorn, D B; Brown, G V; Clementson, J T; Chen, H; Chen, M H; Beiersdorfer, P et al.
Partner: UNT Libraries Government Documents Department
open access

A HAMILTONIAN FORMULATION FOR SPIRAL-SECTOR ACCELERATORS.

Description: I develop a formulation for Hamiltonian dynamics in an accelerator with magnets whose edges follow a spiral. I demonstrate using this Hamiltonian that a spiral FFAG can be made perfectly 'scaling'. I examine the effect of tilting an RF cavity with respect a radial line from the center of the machine, potentially with a different angle than the spiral of the magnets.
Date: November 5, 2007
Creator: Berg, J. S.
Partner: UNT Libraries Government Documents Department
open access

Biosynthesis of a Fully Functional Cyclotide inside Living Bacterial Cells

Description: The cyclotide MCoTI-II is a powerful trypsin inhibitor recently isolated from the seeds of Momordica cochinchinensis, a plant member of cucurbitaceae family. We report for the first time the in vivo biosynthesis of natively-folded MCoTI-II inside live E. coli cells. Our biomimetic approach involves the intracellular backbone cyclization of a linear cyclotide-intein fusion precursor mediated by a modified protein splicing domain. The cyclized peptide then spontaneously folds into its native conf… more
Date: April 5, 2007
Creator: Camarero, J A; Kimura, R H; Woo, Y; Cantor, J & Shekhtman, A
Partner: UNT Libraries Government Documents Department
open access

Ionization efficiency studies for xenon ions with thesuperconducting ECR ion source VENUS

Description: Ionization efficiency studies for high charge state xenon ions using a calibrated gas leak are presented. A 75% enriched {sup 129}Xe gas leak with a gas flow equivalent to 5.11p{mu}A was used in all the measurements. The experiments were performed at the VENUS (Versatile ECR ion source for Nuclear Science) ion source for 18 GHz, 28 GHz and double frequency operation. Overall, total ionization efficiencies close to 100% and ionization efficiencies into a single charge state up to 22% were measur… more
Date: June 5, 2007
Creator: Leitner, Daniela; Lyneis, Claude M.; Todd, DamonS. & Tarvainen,Olli
Partner: UNT Libraries Government Documents Department
open access

Energetics of Multiple-Ion Species Hohlraum Plasmas

Description: A study of the laser-plasma interaction processes in multiple-ion species plasmas has been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. Gas-filled hohlraums with densities of xe22/cc are heated to Te=3keV and backscattered laser light is measured by a suite of absolutely calibrated backscatter diagnostics. Ion Landau damping is increased by adding hydrogen to the CO2/CF4 gas fill. We find that the backscatter from … more
Date: November 5, 2007
Creator: Neumayer, P; Berger, R; Callahan, D; Divol, L; Froula, D; London, R et al.
Partner: UNT Libraries Government Documents Department
open access

Probing degradation in complex engineering silicones by 1H multiple quantum NMR

Description: Static {sup 1}H Multiple Quantum Nuclear Magnetic Resonance (MQ NMR) has recently been shown to provide detailed insight into the network structure of pristine silicon based polymer systems. The MQ NMR method characterizes the residual dipolar couplings of the silicon chains that depend on the average molecular weight between physical or chemical constraints. Recently, we have employed MQ NMR methods to characterize the changes in network structure in a series of complex silicone materials subj… more
Date: September 5, 2007
Creator: Maxwell, R S; Chinn, S C; Giuliani, J & Herberg, J L
Partner: UNT Libraries Government Documents Department
open access

COMPARISON OF RESPONSE OF 9977 TEST PACKAGES TO ANALYTICAL RESULTS

Description: Each of the hypothetical accident test cases for the 9977 prototypes was included in the battery of finite element structural analyses performed for the package. Comparison of the experimental and analytical results provides a means of confirming that the analytical model correctly represents the physical behavior of the package. The ability of the analytical model to correctly predict the performance of the foam overpack material for the crush test is of particular interest. The dissipation of… more
Date: December 5, 2007
Creator: Smith, A & Tsu-Te Wu, T
Partner: UNT Libraries Government Documents Department
open access

Protein Microarrays--Without a Trace

Description: Many experimental approaches in biology and biophysics, as well as applications in diagnosis and drug discovery, require proteins to be immobilized on solid supports. Protein microarrays, for example, provide a high-throughput format to study biomolecular interactions. The technique employed for protein immobilization is a key to the success of these applications. Recent biochemical developments are allowing, for the first time, the selective and traceless immobilization of proteins generated b… more
Date: April 5, 2007
Creator: Camarero, J A
Partner: UNT Libraries Government Documents Department
open access

Influence and measurement of mass ablation in ICF implosions

Description: Point design ignition capsules designed for the National Ignition Facility (NIF) currently use an x-ray-driven Be(Cu) ablator to compress the DT fuel. Ignition specifications require that the mass of unablated Be(Cu), called residual mass, be known to within 1% of the initial ablator mass when the fuel reaches peak velocity. The specifications also require that the implosion bang time, a surrogate measurement for implosion velocity, be known to +/- 50 ps RMS. These specifications guard against … more
Date: September 5, 2007
Creator: Spears, B. K.; Hicks, D.; Velsko, C.; Stoyer, M.; Robey, H.; Munro, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Biological impacts and context of network theory

Description: Many complex systems can be represented and analyzed as networks, and examples that have benefited from this approach span the natural sciences. For instance, we now know that systems as disparate as the World-Wide Web, the Internet, scientific collaborations, food webs, protein interactions and metabolism all have common features in their organization, the most salient of which are their scale-free connectivity distributions and their small-world behavior. The recent availability of large scal… more
Date: January 5, 2007
Creator: Almaas, E
Partner: UNT Libraries Government Documents Department
open access

Experimental Studies of ICF Indirect-Drive Be and High Density C Candidate Ablators

Description: To validate our modeling of the macroscopic and microscopic hydrodynamic and equation of state response of these candidate ablators to NIC-relevant x-ray drive, a multi-lab experimental program has been verifying the behavior of these new ablators. First, the pressures for onset and termination of melt for both Be and HDC under single or double shock drive has been measured at the Z and Omega facilities. Second, the level and effect of hard x-ray preheat has been quantified in scaled experiment… more
Date: September 5, 2007
Creator: Landen, O. L.; Bradley, D. K.; Braun, D. G.; Smalyuk, V. A.; Hicks, D. G.; Celliers, P. M. et al.
Partner: UNT Libraries Government Documents Department
open access

14C/C measurements support Andreev's internode method to determine lichen growth rates in Cladina stygia (Fr.) Ahti

Description: Growth rates and the ability to date an organism can greatly contribute to understanding its population biology and community dynamics. 1n 1954, Andreev proposed a method to date Cladina, a fruticose lichen, using total thallus length and number of internodes. No research, however, has demonstrated the reliability of this technique or compared its estimates to those derived by other means. In this study, we demonstrate the utility of {sup 14}C/C ratios to determine lichen age and growth rate in… more
Date: December 5, 2007
Creator: Holt, E. & Bench, G.
Partner: UNT Libraries Government Documents Department
open access

FUNCTIONALIZED LATERAL SURFACE COATED LASERS FOR CHEM-BIO DETECTION

Description: We present a class of compact, monolithic, photonic sensors consisting of multiple section edge emitting lasers with functionalized lateral surface coatings for low level detection of chemical or biological agents. Specifically, we discuss 8 {micro}m x 250 {micro}m Pd-coated H{sub 2} sensors and configurations to reduce the minimum detection limit from 138ppm for passive sensors to 1ppm for active sensors. Compared with conventional optical H{sub 2} sensors that use fiber gratings, surface plas… more
Date: July 5, 2007
Creator: Goddard, L L; Bond, T C; Cole, G D & Behymer, E M
Partner: UNT Libraries Government Documents Department
open access

Horizontal Shear Wave Imaging of Large Optics

Description: When complete the National Ignition Facility (NIF) will be the world's largest and most energetic laser and will be capable of achieving for the first time fusion ignition in the laboratory. Detecting optics features within the laser beamlines and sizing them at diameters of 0.1 mm to 10 mm allows timely decisions concerning refurbishment and will help with the routine operation of the system. Horizontally polarized shear waves at 10 MHz were shown to accurately detect, locate, and size feature… more
Date: September 5, 2007
Creator: Quarry, M J
Partner: UNT Libraries Government Documents Department
open access

Tracking of Acceleration With Hnj Method.

Description: After reviewing the principle of operation of acceleration with the method of Harmonic Number Jump (HNJ) in a Fixed-Field Alternating-Gradient (FFAG) accelerator for protons and heavy ions, we report in this talk the results of computer simulations performed to assess the capability and the limits of the method in a variety of practical situations. Though the study is not yet completed, and there still remain other cases to be investigated, nonetheless the tracking results so far obtained are v… more
Date: November 5, 2007
Creator: Ruggiero, A. G.
Partner: UNT Libraries Government Documents Department
open access

Simulations of Fracture and Fragmentation of Geologic Materials using Combined FEM/DEM/SPH Analysis

Description: An overview of the Lawrence Discrete Element Code (LDEC) is presented, and results from a study investigating the effect of explosive and impact loading on geologic materials using the Livermore Distinct Element Code (LDEC) are detailed. LDEC was initially developed to simulate tunnels and other structures in jointed rock masses using large numbers of polyhedral blocks. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combi… more
Date: April 5, 2007
Creator: Morris, J. P. & Johnson, S. M.
Partner: UNT Libraries Government Documents Department
open access

EVALUATION OF THERMAL CONDUCTIVITY OF INSTALLED-IN-PLACE POLYURETHANE FOAM INSULATION BY EXPERIMENT AND ANALYSIS

Description: In the thermal analysis of the 9977 package, it was found that calculated temperatures, determined using a typical thermal analysis code, did not match those measured in the experimental apparatus. The analysis indicated that the thermal resistance of the overpack in the experimental apparatus was less than that expected, based on manufacturer's reported value of thermal conductivity. To resolve this question, the thermal conductivity of the installed foam was evaluated from the experimental re… more
Date: December 5, 2007
Creator: Smith, A; Bruce Hardy, B; Kurt Eberl, K & Nick Gupta, N
Partner: UNT Libraries Government Documents Department
open access

Evaluation of radioactive background rejection in 76Ge neutrino-lessdouble-beta decay experiments using a highly segmented HPGe detector

Description: A highly segmented coaxial HPGe detector was operated in a low background counting facility for over 1 year to experimentally evaluate possible segmentation strategies for the proposed Majorana neutrino-less double-beta decay experiment. Segmentation schemes were evaluated on their ability to reject multi-segment events while retaining single-segment events. To quantify a segmentation scheme's acceptance efficiency the percentage of peak area due to single segment events was calculated for peak… more
Date: February 5, 2007
Creator: Chan, Yuen-Dat; Campbell, D. B.; Vetter, K.; Henning, R.; Lesko, K.; Chan, Y. D. et al.
Partner: UNT Libraries Government Documents Department
open access

SAFETY IMPROVES DRAMATICALLY IN FLUOR HANFORD SOIL AND GROUNDWATER REMEDIATION PROJECT

Description: This paper describes dramatic improvements in the safety record of the Soil and Groundwater Remediation Project (SGRP) at the Hanford Site in southeast Washington state over the past four years. During a period of enormous growth in project work and scope, contractor Fluor Hanford reduced injuries, accidents, and other safety-related incidents and enhanced a safety culture that earned the SGRP Star Status in the Department of Energy's (DOE's) Voluntary Protection Program (VPP) in 2007. This pap… more
Date: December 5, 2007
Creator: Gerber, M. S.
Partner: UNT Libraries Government Documents Department
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