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2004 Inorganic Chemistry Gordon Research Conference - July 18-23, 2004

Description: The Gordon Research Conference (GRC) on 2004 Inorganic Chemistry Gordon Research Conference - July 18-23, 2004 was held at Salve Regina College, July 18-23, 2004. The Conference was well-attended with 110 participants (attendees list attached). The attendees represented the spectrum of endeavor in this field coming from academia, industry, and government laboratories, both U.S. and foreign scientists, senior researchers, young investigators, and students. In designing the formal speakers progra… more
Date: September 16, 2005
Creator: Clark, David
open access

2004 Mutagenesis Gordon Conference

Description: Mutations are genetic alterations that drive biological evolution and cause many, if not all, human diseases. Mutation originates via two distinct mechanisms: ''vertical'' variation is de novo change of one or few bases, whereas ''horizontal'' variation occurs by genetic recombination, which creates new mosaics of pre-existing sequences. The Mutagenesis Conference has traditionally focused on the generation of mutagenic intermediates during normal DNA synthesis or in response to environmental i… more
Date: September 16, 2005
Creator: Jinks-Robertson, Dr. Sue
open access

The algebras of large N matrix mechanics

Description: Extending early work, we formulate the large N matrix mechanics of general bosonic, fermionic and supersymmetric matrix models, including Matrix theory: The Hamiltonian framework of large N matrix mechanics provides a natural setting in which to study the algebras of the large N limit, including (reduced) Lie algebras, (reduced) supersymmetry algebras and free algebras. We find in particular a broad array of new free algebras which we call symmetric Cuntz algebras, interacting symmetric Cuntz a… more
Date: September 16, 1999
Creator: Halpern, M.B. & Schwartz, C.
open access

Analysis of a reported magnetic monopole

Description: It is shown that there are several substantive errors in a previous work on a cosmic ray event which is consistent with the hypothesis that it was caused by a magnetic monopole. It is shown that the data points fit to the hypothesis that the responsible particle is a platinum nucleus fragmenting to osmium and then to tantalum. (JFP)
Date: September 16, 1975
Creator: Alvarez, L.W.
open access

An Analytical Model for Solute Transport in Unsaturated Flowthrough a Single Fracture and Porous Rock Matrix

Description: Exact analytical solutions are presented for solute transport in an unsaturated fracture and porous rock matrix. The problem includes advective transport in the fracture and rock matrix as well as advective and diffusive fracture-matrix exchange. Linear sorption in the fracture and matrix and radioactive decay are also treated. The solution is for steady, uniform transport velocities within the fracture and matrix, but allows for independent specification of each of the velocities. The problem … more
Date: September 16, 2004
Creator: Houseworth, J.E.
open access

Application of uncertainty analysis of ignition performance to the Engineering Test Reactor

Description: The design of future Engineering Test Reactor (ETR) to demonstrate ignition is complicated by the uncertainties in the projected database for ignited plasmas. Application of uncertainty analysis to ETR design utilizing a figure-of-merit defined as the probability of ignition is presented. Performance evaluation from the uncertainty analysis in density-temperature space can locate an optimum operating window for ignition. 11 refs., 5 figs., 3 tabs.
Date: September 16, 1988
Creator: Ho, S. K. & Perkins, L. J.
open access

Applications of Event-by-Event Fission Modeling with FREYA

Description: The recently developed code FREYA (Fission Reaction Event Yield Algorithm) generates large samples of complete fission events, consisting of two receding product nuclei as well as a number of neutrons and photons, all with complete kinematic information. Thus it is possible to calculate arbitrary correlation observables whose behavior may provide unique insight into the fission process. We first discuss the present status of FREYA, which has now been extended to include spontaneous fission. Con… more
Date: September 16, 2011
Creator: Vogt, R & Randrup, J
open access

Assessing non-uniqueness: An algebraic approach

Description: Geophysical inverse problems are endowed with a rich mathematical structure. When discretized, most differential and integral equations of interest are algebraic (polynomial) in form. Techniques from algebraic geometry and computational algebra provide a means to address questions of existence and uniqueness for both linear and non-linear inverse problem. In a sense, the methods extend ideas which have proven fruitful in treating linear inverse problems.
Date: September 16, 2002
Creator: Vasco, Don W.
open access

ASSESSMENT OF RADIONUCLIDES DATABASES IN CAP88 MAINFRAME VERSION 1.0 AND WINDOWS-BASED VERSION 3.0

Description: In this study the radionuclide databases for two versions of the Clean Air Act Assessment Package-1988 (CAP88) computer model were assessed in detail. CAP88 estimates radiation dose and the risk of health effects to human populations from radionuclide emissions to air. This program is used by several Department of Energy (DOE) facilities to comply with National Emission Standards for Hazardous Air Pollutants (NESHAP) regulations. CAP88 Mainframe, referred to as Version 1.0 on the Environmental … more
Date: September 16, 2008
Creator: Farfan, E.; Lee, P.; Jannik, T. & Donnelly, E.
open access

Biocorrosive Thermophilic Microbial Communities in Alaskan North Slope Oil Facilities

Description: Corrosion of metallic oilfield pipelines by microorganisms is a costly but poorly understood phenomenon, with standard treatment methods targeting mesophilic sulfatereducing bacteria. In assessing biocorrosion potential at an Alaskan North Slope oil field, we identified thermophilic hydrogen-using methanogens, syntrophic bacteria, peptideand amino acid-fermenting bacteria, iron reducers, sulfur/thiosulfate-reducing bacteria and sulfate-reducing archaea. These microbes can stimulate metal corros… more
Date: September 16, 2009
Creator: Duncan, Kathleen E.; Gieg, Lisa M.; Parisi, Victoria A.; Tanner, Ralph S.; Green Tringe, Susannah; Bristow, Jim et al.
open access

Bounds and self-consistent estimates for elastic constants of random polycrystals with hexagonal, trigonal, and tetragonal symmetries

Description: Peselnick, Meister, and Watt have developed rigorous methods for bounding elastic constants of random polycrystals based on the Hashin-Shtrikman variational principles. In particular, a fairly complex set of equations that amounts to an algorithm has been presented previously for finding the bounds on effective elastic moduli for polycrystals having hexagonal, trigonal, and tetragonal symmetries. The more analytical approach developed here, although based on the same ideas, results in a new set… more
Date: September 16, 2004
Creator: Berger, E. L.
open access

Bremsstrahlung pair-production of positrons with low neutron background.

Description: Minimization of component activation is highly desirable at accelerator-based positron sources. Electrons in the 8- to 14-MeV energy range impinging on a target produce photons energetic enough to create electron-positron pairs; however, few of the photons are energetic enough to produce photoneutrons. Slow positron production by low-energy electrons impinging on a multilayer tungsten target with and without electromagnetic extraction between the layers was studied by simulation. The neutron ba… more
Date: September 16, 1998
Creator: Lessner, E.
open access

The C-Cat Wordnet Package: An Open Source Package for modifying andapplying Wordnet

Description: We present the C-Cat Wordnet package, an open source library for using and modifying Wordnet. The package includes four key features: an API for modifying Synsets; implementations of standard similarity metrics, implementations of well known Word Sense Disambiguation algorithms, and an implementation of the Castanet algorithm. The library is easily extendible and usable in many runtime environments. We demonstrate it's use on two standard Word Sense Disambiguation tasks and apply the Castanet a… more
Date: September 16, 2011
Creator: Stevens, K; Huang, T & Buttler, D
open access

Characterization of High-Temperature Laser-Produced Plasmas Using Thomson Scattering

Description: Ultraviolet Thomson scattering has been fielded at the Omega Laser Facility to achieve accurate measurements of the plasma conditions in laser-produced high-temperature plasmas. Recent applications to hohlraum targets that have been filled with CH gas or SiO{sub 2} foams have demonstrated a new high temperature plasma regime of importance to laser-plasma interaction studies in a strongly damped regime such as those occurring in indirect drive inertial confinement fusion experiments. The Thomson… more
Date: September 16, 2005
Creator: Glenzer, S H; Froula, D H; Ross, S; Niemann, C; Meezan, N & Divol, L
open access

CHARACTERIZATION OF PLASTICALLY-INDUCED STRUCTURAL CHANGES IN A Zr-BASED BULK METALLIC GLASS USING POSITRON ANNIHILATION SPECTROCOPY

Description: Flow in metallic glasses is associated with stress-induced cooperative rearrangements of small groups of atoms involving the surrounding free volume. Understanding the details of these rearrangements therefore requires knowledge of the amount and distribution of the free volume and how that distribution evolves with deformation. The present study employs positron annihilation spectroscopy to investigate the free volume change in Zr{sub 58.5}Cu{sub 15.6}Ni{sub 12.8}Al{sub 10.3}Nb{sub 2.8} bulk m… more
Date: September 16, 2005
Creator: Flores, K M; Kanungo, B P; Glade, S C & Asoka-Kumar, P
open access

Cluster-Molecule Systems: Analysis and Tuning of the Interaction Potential

Description: The interaction (modelled by a LEPS potential) of a D[sub 2] molecule with an icosahedral Ni[sub 13] cluster is mapped and analyzed in the form of equipotential contour plots. The topological features of the map correlate with the energetic and dynamical characteristics of the dissociative adsorption of the molecule on the cluster, which were extracted from quasiclassical trajectory simulations. A modification of the LEPS potential used originally is introduced. It brings the calculated reactiv… more
Date: September 16, 1992
Creator: Jellinek, J. & Guevenc, Z. B.
open access

Cluster-molecule systems: Analysis and tuning of the interaction potential

Description: The interaction (modelled by a LEPS potential) of a D{sub 2} molecule with an icosahedral Ni{sub 13} cluster is mapped and analyzed in the form of equipotential contour plots. The topological features of the map correlate with the energetic and dynamical characteristics of the dissociative adsorption of the molecule on the cluster, which were extracted from quasiclassical trajectory simulations. A modification of the LEPS potential used originally is introduced. It brings the calculated reactiv… more
Date: September 16, 1992
Creator: Jellinek, J. & Guevenc, Z. B.
open access

Comparative analysis of internal fuel motion in annular fuel designs

Description: In this paper, the whole-core reactivity consequences of internal fuel motion in three annular fuel designs during a hypothetical 3 dollars/s transient overpower (TOP) accident are compared to determine the effect of geometric design variations. The PINEX-2 and PINEX-3 experiments were performed in the TREAT reactor using annular fuel pins irradiated in GETR. This paper investigates three combinations of solid and annular axial blankets and fission gas plena: top annular blanket and plenum, bot… more
Date: September 16, 1983
Creator: Smith, D. E.
open access

A Comparison of Kretschmann-Raether Angular Regimes for Measuring Changes in Bulk Refractive Index

Description: We compare 2 angular regimes for the measurement of changes in the real refractive index of bulk fluid analytes. The measurements are based on the use of the Kretschmann-Raether configuration to sense a change in reflectivity with index. Specifically, we numerically simulate the relative sensitivities of the total internal reflection (TIR) and surface-plasmon resonance (SPR) regimes. For a fixed-angle apparatus, the method which gives the greatest change in reflectivity varies with metal film t… more
Date: September 16, 1999
Creator: KASUNIC, K.J.
open access

A Concept for Zero-Alignment Micro Optical Systems

Description: We are developing a method of constructing compact, three-dimensional photonics systems consisting of optical elements, e.g., lenses and mirrors, photo-detectors, and light sources, e.g., VCSELS or circular-grating lasers. These optical components, both active and passive, are mounted on a lithographically prepared silicon substrate. We refer to the substrate as a micro-optical table (MOT) in analogy with the macroscopic version routinely used in optics laboratories. The MOT is a zero-alignment… more
Date: September 16, 1999
Creator: DESCOUR, MICHAEL R.; KOLOLUOMA,TERHO; LEVEY,RAVIV; RANTALA,JUHA T.; SHUL,RANDY J.; WARREN,MIAL E. et al.
open access

Coupled Resonator Vertical Cavity Laser Diode

Description: We report the operation of an electrically injected monolithic coupled resonator vertical cavity laser which consists of an active cavity containing In{sub x}Ga{sub 1{minus}x}As quantum wells optically coupled to a passive GaAs cavity. This device demonstrates novel modulation characteristics arising from dynamic changes in the coupling between the active and passive cavities. A composite mode theory is used to model the output modulation of the coupled resonator vertical cavity laser. It is sh… more
Date: September 16, 1999
Creator: CHOQUETTE, KENT D.; CHOW, WENG W.; FISCHER, ARTHUR J.; GEIB, KENT M. & HOU, HONG Q.
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