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Physical and Chemical Analytical Analysis: A key component of Bioforensics

Description: The anthrax letters event of 2001 has raised our awareness of the potential importance of non-biological measurements on samples of biological agents used in a terrorism incident. Such measurements include a variety of mass spectral, spectroscopic, and other instrumental techniques that are part of the current armamentarium of the modern materials analysis or analytical chemistry laboratory. They can provide morphological, trace element, isotopic, and other molecular ''fingerprints'' of the age… more
Date: February 15, 2005
Creator: Velsko, S P
Item Type: Refine your search to only Article
open access

A Model Study of Transverse Mode Coupling Instability at National Synchrotron Light Source-II (Nsls-II).

Description: The vertical impedances of the preliminary designs of National Synchrotron Light Source II (NSLS-II) Mini Gap Undulators (MGU) are calculated by means of GdfidL code. The Transverse Mode Coupling Instability (TMCI) thresholds corresponding to these impedances are estimated using an analytically solvable model.
Date: May 15, 2005
Creator: Blednykh, A. & Wang, J. M.
Item Type: Refine your search to only Article
open access

RESEARCH AND DEVELOPMENT OF A VARIABLE POLARIZATION SUPERCONDUCTING UNDULATOR AT THE NSLS.

Description: In this paper a new concept for a planar, superconductive, variable polarization undulator (VPU) is presented. Advantage of this design include: (1) electrical tunability for both right and left circular and elliptical, as well as linear vertical or horizontal, (2) it requires no compensation of unwanted vertical field component and (3) used only simple windings of superconductive wire in an interlaced pattern. The construction of the device is described and compared with a permanent magnet VPU… more
Date: May 15, 2005
Creator: CHOUHAN, S.; HARDER, D.; RAKOWSKY, G. & AL., ET
Item Type: Refine your search to only Article
open access

Influence of Nitrate on the Hanford 100D Area In Situ Redox Manipulation Barrier Longevity

Description: The purpose of this laboratory study is to determine the influence of nitrate on the Hanford 100D Area in situ redox manipulation (ISRM) barrier longevity. There is a wide spread groundwater plume of 60 mg/L nitrate upgradient of the ISRM barrier with lower nitrate concentrations downgradient, suggestive of nitrate reduction occurring. Batch and 1-D column experiments showed that nitrate is being slowly reduced to nitrite and ammonia. These nitrate reduction reactions are predominantly abiotic,… more
Date: July 15, 2005
Creator: Szecsody, Jim E.; Phillips, Jerry L.; Vermeul, Vince R.; Fruchter, Jonathan S. & Williams, Mark D.
Item Type: Refine your search to only Report
open access

Density Measurements of Be Shells

Description: The purpose of this memo is to lay out the uncertainties associated with the measurement of density of Be ablators by the weigh and volume method. I am counting on the readers to point out any faulty assumptions about the techniques or uncertainties associated with them. Based on the analysis presented below we should expect that 30 {micro}m thick shells will have an uncertainty in the measured density of about 2% of the value, coming more or less equally from the mass and volume measurement. T… more
Date: February 15, 2005
Creator: Cook, R C
Item Type: Refine your search to only Report
open access

The Influence of Selected Liquid and Soil Properties on the Propagation of Spills over Flat Permeable Surfaces

Description: In an effort to determine spill characteristics, information about a spill's spatial distribution with time is being studied. For permeable surfaces, spill phenomenology is controlled by liquid and soil properties, the most relevant of which are presented in this report. The pertinent liquid and soil properties were tabulated for ten liquids and four soils. The liquids represented an array of organic compounds, some of which are or are soon to be documented in the liquid spectra library by the … more
Date: February 15, 2005
Creator: Keller, Jason M. & Simmons, Carver S.
Item Type: Refine your search to only Report
open access

Ultrasonic Examination of Double-Shell Tank 241-AP-104. February 2005

Description: COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AP-104. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary and secondary tank. The requirements for the ultrasonic examination of Tank 241-AP-104 were to detect, characterize (identify, size, and locate), and record me… more
Date: March 15, 2005
Creator: Pardini, Allan F. & Posakony, Gerald J.
Item Type: Refine your search to only Report
open access

Harmonic Cavity Performance for NSLS-II

Description: NSLS-II is a 3 GeV ultra-high brightness storage ring planned to succeed the present NSLS rings at BNL. Ultralow emittance combined with short bunch length means that it is critical to minimize the effects of Touschek scattering and coherent instabilities. Improved lifetime and stability can be achieved by including a third-harmonic RF cavity in the baseline design. This paper describes the required harmonic RF parameters and the expected system performance.
Date: May 15, 2005
Creator: Blednykh, A.; Krinsky, S.; Podobedov, B.; Rose, J.; Towne, N. & Wang, J. M.
Item Type: Refine your search to only Article
open access

DYNAMIC APERTURE OPTIMIZATION FOR LOW EMITTANCE LIGHT SOURCES.

Description: State of the art low emittance light source lattices, require small bend angle dipole magnets and strong quadrupoles. This in turn creates large chromaticity and small value of dispersion in the lattice. To counter the high linear chromaticity, strong sextupoles are required which limit the dynamic aperture. Traditional methods for expanding the dynamic aperture use harmonic sextupoles to counter the tune shift with amplitude. This has been successful up to now, but is non-deterministic and lim… more
Date: May 15, 2005
Creator: KRAMER, S. & BENGTSSON, J.
Item Type: Refine your search to only Article
open access

Inverse Scattering Approach to Improving Pattern Recognition

Description: The Helmholtz machine provides what may be the best existing model for how the mammalian brain recognizes patterns. Based on the observation that the ''wake-sleep'' algorithm for training a Helmholtz machine is similar to the problem of finding the potential for a multi-channel Schrodinger equation, we propose that the construction of a Schrodinger potential using inverse scattering methods can serve as a model for how the mammalian brain learns to extract essential information from sensory dat… more
Date: February 15, 2005
Creator: Chapline, G & Fu, C
Item Type: Refine your search to only Article
open access

CONTROL OF DYNAMIC APERTURE FOR SYNCHROTRON LIGHT SOURCES.

Description: A summary of how modern analytical and numerical techniques enable one to construct a realistic model of state-of-the-art synchrotron light sources is provided. The effects of engineering tolerances and radiation are included in a self-consistent manner. An approach for utilizing these tools to develop an effective strategy for the design and control of the dynamic aperture for such dynamical systems is also outlined.
Date: May 15, 2005
Creator: BENGTSSON, J.
Item Type: Refine your search to only Article
open access

Predicting Peak Hydrogen Concentrations from Spontaneous Gas Releases in Hanford Waste Tanks

Description: Buoyant displacement gas release events (BDGRE) are spontaneous gas releases that occur in a few of the Hanford radioactive waste storage tanks when gas accumulation makes the sediment layer buoyant with respect to the liquid. BDGREs are assumed to be likely if the ratio of the predicted sediment gas fraction and neutral buoyancy gas fraction, or buoyancy ratio, exceeds unity. Based on the observation that the buoyancy ratio is also an empirical indicator of BDGRE size, a new methodology is der… more
Date: July 15, 2005
Creator: Stewart, Charles W.; Hartley, Stacey A.; Meyer, Perry A. & Wells, Beric E.
Item Type: Refine your search to only Report
open access

The crystal structure of Rv1347c, a putative antibiotic resistance protein from Mycobacterium tuberculosis, reveals a GCN5-related fold and suggests an alternative function in siderophore biosynthesis

Description: Mycobacterium tuberculosis, the cause of TB, is a devastating human pathogen. The emergence of multi-drug resistance in recent years has prompted a search for new drug targets and for a better understanding of mechanisms of resistance. Here we focus on the gene product of an open reading frame from M. tuberculosis, Rv1347c, which is annotated as a putative aminoglycoside N-acetyltransferase. The Rv1347c protein does not show this activity, however, and we show from its crystal structure, couple… more
Date: February 15, 2005
Creator: Card, G. L.; Peterson, N. A.; Smith, C. A.; Rupp, B.; Schick, B. M. & Baker, E. N.
Item Type: Refine your search to only Article
open access

Impedance of Finite Length Resistor

Description: We determine the impedance of a cylindrical metal tube (resistor) of radius a, length g, and conductivity {sigma}, attached at each end to perfect conductors of semi-infinite length. Our main interest is in the asymptotic behavior of the impedance at high frequency, k >> 1/a. In the equilibrium regime, , the impedance per unit length is accurately described by the well-known result for an infinite length tube with conductivity {sigma}. In the transient regime, ka{sup 2} >> g, we der… more
Date: May 15, 2005
Creator: Krinsky, S.; Podobedov, B. & Gluckstern, R. L.
Item Type: Refine your search to only Article
open access

Appendix D-21 Building 696S Consolidation Waste Accumulation Area

Description: This appendix is designed to provide information specific to the Building 696S Consolidation Waste Accumulation Area (B-696S CWAA), a waste storage area. The appendix is not designed to be used as a sole source of information. All general information that is not specific to the B-696S CWAA is included in the Contingency Plan for Waste Accumulation Areas, dated July 2004, and should be referenced.
Date: April 15, 2005
Creator: Michalik, R L
Item Type: Refine your search to only Report
open access

Ceramic Laser Materials

Description: Transparent ceramic materials have several major advantages over single crystals in laser applications, not the least of which is the ability to make large aperture parts in a robust manufacturing process. After more than a decade of working on making transparent YAG:Nd, Japanese workers have recently succeeded in demonstrating samples that performed as laser gain media as well as their single crystal counterparts. Since then several laser materials have been made and evaluated. For these reaso… more
Date: February 15, 2005
Creator: Soules, T F; Clapsaddle, B J; Landingham, R L & Schaffers, K I
Item Type: Refine your search to only Report
open access

Data Analysis of Plutonium Sorption on Colloids in a Minimal Kinetics Model

Description: We considered a sorption model containing the minimal dynamic features of the system to fit plutonium adsorption data similar to that developed by Painter et al. (2002). Global fits to recent data favored nonzero values of reversible sorption, allowing the definition of equilibrium distribution coefficients in all cases except the synthetic form of montmorillonite. In most cases, the two-site model was adequate to fit the data. The model represents a mathematic simplification of the time-depend… more
Date: August 15, 2005
Creator: Wittman, Richard S.; Buck, Edgar C. & Hanson, Brady D.
Item Type: Refine your search to only Report
open access

2005 Annual Report Summer Research Institute Interfacial and Condensed Phase Chemical Physics

Description: The Pacific Northwest National Laboratory (PNNL) hosted its second annual Summer Research Institute in Interfacial and Condensed Phase Chemical Physics from May through September 2005. During this period, sixteen PNNL scientists hosted fourteen young scientists from eleven different universities. Of the fourteen participants, twelve were graduate students; one was a postdoctoral fellow; and one was a university faculty member.
Date: November 15, 2005
Creator: Barlow, Stephan E.
Item Type: Refine your search to only Report
open access

Topology Changing Transitions in Bubbling Geometries

Description: Topological transitions in bubbling half-BPS Type IIB geometries with SO(4) x SO(4) symmetry can be decomposed into a sequence of n elementary transitions. The half-BPS solution that describes the elementary transition is seeded by a phase space distribution of fermions filling two diagonal quadrants. We study the geometry of this solution in some detail. We show that this solution can be interpreted as a time dependent geometry, interpolating between two asymptotic pp-waves in the far past and… more
Date: February 15, 2005
Creator: Horava, Petr & Shepard, Peter G.
Item Type: Refine your search to only Article
open access

Topology Changing Transitions in Bubbling Geometries

Description: Topological transitions in bubbling half-BPS Type IIB geometries with SO(4) x SO(4) symmetry can be decomposed into a sequence of n elementary transitions. The half-BPS solution that describes the elementary transition is seeded by a phase space distribution of fermions filling two diagonal quadrants. We study the geometry of this solution in some detail. We show that this solution can be interpreted as a time dependent geometry, interpolating between two asymptotic pp-waves in the far past and… more
Date: February 15, 2005
Creator: Horava, Petr & Shepard, Peter G.
Item Type: Refine your search to only Article
open access

Evaluation of production samples of the scintillators LaBr3:Ce and LaCl3:Ce

Description: We report on the evaluation of the performance of two recently developed scintillator materials, LaCl{sub 3}:Ce and LaBr{sub 3}:Ce, at the task of gamma ray spectroscopy. Their performance is compared to a standard scintillator used for gamma ray spectroscopy--a 25 mm diameter 25 mm tall cylinder of NaI:Tl. We measure the pulse height, energy resolution, and full-energy efficiency of production LaBr{sub 3}:Ce and LaCl{sub 3}:Ce scintillation crystals of different sizes and geometries for a vari… more
Date: September 15, 2005
Creator: Choong, Woon-Seng; Derenzo, Stephen E. & Moses, William W.
Item Type: Refine your search to only Article
open access

Comparing FRACHEM and TOUGHREACT for reactive transport modelingof brine-rock interactions in enhanced geothermal systems (EGS)

Description: Coupled modelling of fluid flow and reactive transport ingeothermal systems is challenging because of reservoir conditions such ashigh temperatures, elevated pressures and sometimes high salinities ofthe formation fluids. Thermal hydrological-chemical (THC) codes, such asFRACHEM and TOUGHREACT, have been developed to evaluate the long-termhydrothermal and chemical evolution of exploited reservoirs. In thisstudy, the two codes were applied to model the same geothermal reservoir,to forecast reser… more
Date: November 15, 2005
Creator: Andre, L.; Spycher, N.; Xu, T.; Pruess, K. & Vuataz, F.-D.
Item Type: Refine your search to only Article
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