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Calcium Carbonate Storage in Amorphous Form and Its Template-Induced Crystallization

Description: Calcium carbonate crystallization in organisms often occurs through the transformation from the amorphous precursor. It is believed that the amorphous phase could be temporarily stabilized and stored, until its templated transition to the crystalline form is induced. Here we develop a bio-inspired crystallization strategy that is based on the above mechanism. Amorphous calcium carbonate (ACC) spherulitic particles are formed and stabilized on a self-assembled monolayer (SAM) of hydroxy-terminat… more
Date: August 31, 2007
Creator: Han, T Y & Aizenberg, J
Partner: UNT Libraries Government Documents Department
open access

LISSAT Analysis of a Generic Centrifuge Enrichment Plant

Description: The U.S. Department of Energy (DOE) is interested in developing tools and methods for use in designing and evaluating safeguards systems for current and future plants in the nuclear power fuel cycle. The DOE is engaging several DOE National Laboratories in efforts applied to safeguards for chemical conversion plants and gaseous centrifuge enrichment plants. As part of the development, Lawrence Livermore National Laboratory has developed an integrated safeguards system analysis tool (LISSAT). Th… more
Date: May 31, 2007
Creator: Lambert, H; Elayat, H A; O?Connell, W J; Szytel, L & Dreicer, M
Partner: UNT Libraries Government Documents Department
open access

Experimental and theoretical studies of particle generation afterlaser ablation of copper with background gas at atmosphericpressure

Description: Laser ablation has proven to be an effective method for generating nanoparticles; particles are produced in the laser induced vapor plume during the cooling stage. To understand the in-situ condensation process, a series of time resolved light scattering images were recorded and analyzed. Significant changes in the condensation rate and the shape of the condensed aerosol plume were observed in two background gases, helium and argon. The primary particle shape and size distribution were measured… more
Date: May 31, 2007
Creator: Wen, Sy-Bor; Mao, Xianglei; Greif, Ralph & Russo, Richard E.
Partner: UNT Libraries Government Documents Department
open access

ITER Shape Controller and Transport Simulations

Description: We currently use the CORSICA integrated modeling code for scenario studies for both the DIII-D and ITER experiments. In these simulations, free- or fixed-boundary equilibria are simultaneously converged with thermal evolution determined from transport models providing temperature and current density profiles. Using a combination of fixed boundary evolution followed by free-boundary calculation to determine the separatrix and coil currents. In the free-boundary calculation, we use the state-spac… more
Date: May 31, 2007
Creator: Casper, T A; Meyer, W H; Pearlstein, L D & Portone, A
Partner: UNT Libraries Government Documents Department
open access

Optical alignment techniques for line-imaging velocity interferometry and line-imaging self-emulsion of targets at the National Ignition Facility (NIF)

Description: The National Ignition Facility (NIF) requires optical diagnostics for measuring shock velocities in shock physics experiments. The Velocity Interferometer System for Any Reflector (VISAR) measures shock velocities, shock breakout times, and emission of 1- to 5-mm targets at a location remote to the NIF target chamber. Three optical systems using the same vacuum chamber port each have a total track of 69 feet. All optical lenses are on kinematic mounts or sliding rails, enabling pointing accurac… more
Date: August 31, 2007
Creator: Robert M. Malone, Brent C. Frogget, Morris I. Kaufman, Thomas W. Tunnell, Robert L. Guyton, Imants P. Reinbachs, Phillip W. Watts, et al.
Partner: UNT Libraries Government Documents Department
open access

Leakage of CO2 from geologic storage: Role of secondary accumulation at shallow depth

Description: Geologic storage of CO2 can be a viable technology forreducing atmospheric emissions of greenhouse gases only if it can bedemonstrated that leakage from proposed storage reservoirs and associatedhazards are small or can be mitigated. Risk assessment must evaluatepotential leakage scenarios and develop a rational, mechanisticunderstanding of CO2 behavior during leakage. Flow of CO2 may be subjectto positive feedbacks that could amplify leakage risks and hazards,placing a premium on identifying a… more
Date: May 31, 2007
Creator: Pruess, K.
Partner: UNT Libraries Government Documents Department
open access

Mercuric Iodide Photocell Technology for Room Temperature Readout of Scintillators

Description: Mercuric iodide (HgI2) is a well known material for the direct detection of gamma rays; however, the largest volume achievable is limited by thickness of the detector, which needs to be a small fraction of the average trapping length for electrons. We are reporting here preliminary results in using HgI2 crystals to fabricate photocells used in the readout of various scintillators. The optical spectral response and efficiency of these photocells were measured and will be reported. Preliminary nu… more
Date: August 31, 2007
Creator: al., Warnick Kernan et
Partner: UNT Libraries Government Documents Department
open access

Comparison between S/1 and R/1 tests and damage density vs. fluence (rho(phi)) results for unconditioned and sub-nanosecond laser-conditioned KD2PO4 crystals

Description: We present S/1 and R/1 test results on unconditioned and 355 nm (3{omega}), 500 ps laser conditioned DKDP. We find up to {approx}2.5X improvement in fluence in the S/1 performance after 3{omega}, 500 ps conditioning to 5 J/cm{sup 2}. For the first time, we observe a shift to higher fluences in the R/1 results for DKDP at 3{omega}, 7 ns due to 500 ps laser conditioning. The S/1 results are compared to {rho}({phi}) results previously measured on the same DKDP crystal [1]. A consistent behavior in… more
Date: October 31, 2007
Creator: Adams, J. J.; Jarboe, J.; Feit, M. & Hackel, R.
Partner: UNT Libraries Government Documents Department
open access

The morphologies of breast cancer cell lines in three-dimensionalassays correlate with their profiles of gene expression

Description: 3D cell cultures are rapidly becoming the method of choice for the physiologically relevant modeling of many aspects of non-malignant and malignant cell behavior ex vivo. Nevertheless, only a limited number of distinct cell types have been evaluated in this assay to date. Here we report the first large scale comparison of the transcriptional profiles and 3D cell culture phenotypes of a substantial panel of human breast cancer cell lines. Each cell line adopts a colony morphology of one of four … more
Date: January 31, 2007
Creator: Kenny, Paraic A.; Lee, Genee Y.; Myers, Connie A.; Neve, RichardM.; Semeiks, Jeremy R.; Spellman, Paul T. et al.
Partner: UNT Libraries Government Documents Department
open access

A Generalized Eigensolver based on Smoothed Aggregation (GES-SA) for Initializing Smoothed Aggregation Multigrid (SA)

Description: Consider the linear system Ax = b, where A is a large, sparse, real, symmetric, and positive definite matrix and b is a known vector. Solving this system for unknown vector x using a smoothed aggregation multigrid (SA) algorithm requires a characterization of the algebraically smooth error, meaning error that is poorly attenuated by the algorithm's relaxation process. For relaxation processes that are typically used in practice, algebraically smooth error corresponds to the near-nullspace of A.… more
Date: May 31, 2007
Creator: Brezina, M; Manteuffel, T; McCormick, S; Ruge, J; Sanders, G & Vassilevski, P S
Partner: UNT Libraries Government Documents Department
open access

Michrochannel plate for position sensitive alpha particle detection

Description: This paper will describe the use of a microchannel plate (MCP) as the associated particle detector on a sealed tube neutron generator. The generator produces neutrons and associated alpha particles for use as a probe to locate and identify hidden explosives in associated particle imaging (API). The MCP measures the position in two dimensions and precise timing of the incident alpha particle, information which is then used to calculate the emission time and direction of the corresponding neutron… more
Date: August 31, 2007
Creator: Tinsley, Paul Hurley and James
Partner: UNT Libraries Government Documents Department
open access

Electromigration-induced plasticity and texture in Cu interconnects

Description: Plastic deformation has been observed in damascene Cu interconnect test structures during an in-situ electromigration experiment and before the onset of visible microstructural damage (ie. voiding) using a synchrotron technique of white beam X-ray microdiffraction. We show here that the extent of this electromigration-induced plasticity is dependent on the texture of the Cu grains in the line. In lines with strong <111> textures, the extent of plastic deformation is found to be relatively… more
Date: October 31, 2007
Creator: Source, Advanced Light; Tamura, Nobumichi; Budiman, A. S.; Hau-Riege, C.S.; Besser, P. R.; Marathe, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Electrokinetic Hydrogen Generation from Liquid WaterMicrojets

Description: We describe a method for generating molecular hydrogen directly from the charge separation effected via rapid flow of liquid water through a metal orifice, wherein the input energy is the hydrostatic pressure times the volume flow rate. Both electrokinetic currents and hydrogen production rates are shown to follow simple equations derived from the overlap of the fluid velocity gradient and the anisotropic charge distribution resulting from selective adsorption of hydroxide ions to the nozzle su… more
Date: May 31, 2007
Creator: Duffin, Andrew M. & Saykally, Richard J.
Partner: UNT Libraries Government Documents Department
open access

PRIME VALUE METHOD TO PRIORITIZE RISK HANDLING STRATEGIES

Description: Funding for implementing risk handling strategies typically is allocated according to either the risk-averse approach (the worst risk first) or the cost-effective approach (the greatest risk reduction per implementation dollar first). This paper introduces a prime value approach in which risk handling strategies are prioritized according to how nearly they meet the goals of the organization that disburses funds for risk handling. The prime value approach factors in the importance of the project… more
Date: October 31, 2007
Creator: Noller, D
Partner: UNT Libraries Government Documents Department
open access

Uncharted Microbial World: Microbes and Their Activities in the Environment

Description: Microbes are the foundation for all of life. From the air we breathe to the soil we rely on for farming to the water we drink, everything humans need to survive is intimately coupled with the activities of microbes. Major advances have been made in the understanding of disease and the use of microorganisms in the industrial production of drugs, food products and wastewater treatment. However, our understanding of many complicated microbial environments (the gut and teeth), soil fertility, and b… more
Date: December 31, 2007
Creator: Harwood, Caroline & Buckley, Merry.
Partner: UNT Libraries Government Documents Department
open access

Microgrids and Heterogeneous Security, Quality, Reliability, andAvailability

Description: This paper describes two stylized alternative visions inpopular currencyof how the power system might evolve to meet futurerequirements for the high quality electricity service that modern digitaleconomies demand, a supergrids paradigm and a dispersed paradigm. Some ofthe economics of the dispersed vision are explored. Economic perspectivesare presented on both the choice of homogeneous universal power qualityupstream in the electricity supply, and also on the extremelyheterogeneous require-men… more
Date: January 31, 2007
Creator: Marnay, Chris
Partner: UNT Libraries Government Documents Department
open access

Flat-Field Calibration of CCD Detector for Long TraceProfilers

Description: The next generation of synchrotrons and free electron lasersrequires x-ray optical systems with extremely high-performance,generally, of diffraction limited quality. Fabrication and use of suchoptics requires highly accurate metrology. In the present paper, wediscuss a way to improve the performance of the Long Trace Profiler(LTP), a slope measuring instrument widely used at synchrotron facilitiesto characterize x-ray optics at high-spatial-wavelengths fromapproximately 2 mm to 1 m. One of the … more
Date: July 31, 2007
Creator: Kirschman, Jonathan L.; Domning, Edward E.; Franck, Keith D.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R. et al.
Partner: UNT Libraries Government Documents Department
open access

Field Deployable Gamma Radiation Detectors for DHS Use

Description: Recently, the U.S. Department of Homeland Security (DHS) has integrated all nuclear detection research, development, testing, evaluation, acquisition, and operational support into a single office: the Domestic Nuclear Detection Office (DNDO). The DNDO has specific requirements set for all commercial and government off-the-shelf radiation detection equipment and data acquisition systems. This article would investigate several recent developments in field deployable gamma radiation detectors that… more
Date: August 31, 2007
Creator: Mukhopadhyay, Sanjoy
Partner: UNT Libraries Government Documents Department
open access

TEMPEST Simulations of Collisionless Damping of Geodesic-Acoustic Mode in Edge Plasma Pedestal

Description: The fully nonlinear 4D TEMPEST gyrokinetic continuum code produces frequency, collisionless damping of geodesic-acoustic mode (GAM) and zonal flow with fully nonlinear Boltzmann electrons for the inverse aspect ratio {epsilon}-scan and the tokamak safety factor q-scan in homogeneous plasmas. The TEMPEST simulation shows that GAM exists in edge plasma pedestal for steep density and temperature gradients, and an initial GAM relaxes to the standard neoclassical residual, rather than Rosenbluth-Hin… more
Date: May 31, 2007
Creator: Xu, X; Xiong, Z; Nevins, W & McKee, G
Partner: UNT Libraries Government Documents Department
open access

The Genomes On Line Database (GOLD) in 2007: status of genomic and metagenomic projects and their associated metadata

Description: The Genomes On Line Database (GOLD) is a comprehensive resource of information for genome and metagenome projects world-wide. GOLD provides access to complete and ongoing projects and their associated metadata through pre-computed lists and a search page. The database currently incorporates information for more than 2900 sequencing projects, of which 639 have been completed and the data deposited in the public databases. GOLD is constantly expanding to provide metadata information related to th… more
Date: December 31, 2007
Creator: Fenner, Marsha W; Liolios, Konstantinos; Mavromatis, Konstantinos; Tavernarakis, Nektarios & Kyrpides, Nikos C.
Partner: UNT Libraries Government Documents Department
open access

Proposal for a Universal Test Mirror for Characterization of SlopeMeasuring Instruments

Description: The development of third generation light sources like theAdvanced Light Source (ALS) or BESSY II brought to a focus the need forhigh performance synchrotron optics with unprecedented tolerances forslope error and micro roughness. Proposed beam lines at Free ElectronLasers (FEL) require optical elements up to a length of one meter,characterized by a residual slope error in the range of 0.1murad (rms),and rms values of 0.1 nm for micro roughness. These optical elements mustbe inspected by highly… more
Date: July 31, 2007
Creator: Yashchuk, Valeriy V.; McKinney, Wayne R.; Warwick, Tony; Noll,Tino; Siewert, Frank; Zeschke, Thomas et al.
Partner: UNT Libraries Government Documents Department
open access

Modeling Efforts to Aid in the Prediction of Process Enrichment Levels with the Intent of Identifying Potential Material Diversion

Description: As part of an ongoing effort at Lawrence Livermore National Laboratory (LLNL) to enhance analytical models that simulate enrichment and conversion facilities, efforts are underway to develop routines to estimate the total gamma-ray flux and that of specific lines around process piping containing UF{sub 6}. The intent of the simulation modeling effort is to aid in the identification of possible areas where material diversion could occur, as input to an overall safeguards strategy. The operation … more
Date: May 31, 2007
Creator: Guenther, C F; Elayat, H A; O?Connell, W J & Lambert, H E
Partner: UNT Libraries Government Documents Department
open access

Design, construction, alignment, and calibration of a compact velocimetry experiment

Description: A velocimetry experiment has been designed to measure shock properties for small, cylindrical, metal targets (8 mm diameter × 2 mm thick). A target is accelerated by high explosives, caught, then retrieved for later inspection. The target is expected to move at a velocity of 0.1 to 3 km/sec. The complete experiment canister is ~105 mm in diameter and 380 mm long. Optical velocimetry diagnostics include the Velocity Interferometer System for Any Reflector (VISAR) and photon Doppler velocimetry (… more
Date: August 31, 2007
Creator: Kaufman, Morris I.; Malone, Robert M.; Frogget, Brent C.; Romero, Vincent T.; Esquibel, David L.; Iverson, Adam et al.
Partner: UNT Libraries Government Documents Department
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