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Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Dynamic Power Flow Controller: Compact Dynamic Phase Angle Regulators for Transmission Power Routing  

SciTech Connect

GENI Project: Varentec is developing compact, low-cost transmission power controllers with fractional power rating for controlling power flow on transmission networks. The technology will enhance grid operations through improved use of current assets and by dramatically reducing the number of transmission lines that have to be built to meet increasing contributions of renewable energy sources like wind and solar. The proposed transmission controllers would allow for the dynamic control of voltage and power flow, improving the grids ability to dispatch power in real time to the places where it is most needed. The controllers would work as fail-safe devices whereby the grid would be restored to its present operating state in the event of a controller malfunction instead of failing outright. The ability to affordably and dynamically control power flow with adequate fail-safe switchgear could open up new competitive energy markets which are not possible under the current regulatory structure and technology base.

None

2012-01-03T23:59:59.000Z

2

Can Dynamic Contact Angle Be Measured Using Molecular Modeling?  

E-Print Network (OSTI)

A method is presented for determining the dynamic contact angle at the three-phase contact between a solid, a liquid, and a vapor under an applied force, using molecular simulation. The method is demonstrated using a ...

Malani, Ateeque A. A. G.

3

Eastern Interconnection Phase Angle Base Lining Study  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

bhargava@electricpowergroup.com June 27-28, 2013 Washington, DC DOE/OE Transmission Reliability Program Topics  Project objective  Major technical accomplishments that will be completed this year-stage in RD&D cycle  Deliverables and schedule for activities to be completed under FY13 funding  Risk factors affecting timely completion of planned activities as well as movement through RD&D cycle  Early thoughts on follow-on work that should be considered for funding in FY14 Project Objective  Operators monitor power flows at specific interchange points (such as Keystone-Juniata). However, power flows may not be a good measure of wide area system stress  Phasor networks provide the capability to monitor phase angle

4

Definition: Phase Angle Regulating Transformer | Open Energy Information  

Open Energy Info (EERE)

Angle Regulating Transformer Angle Regulating Transformer Jump to: navigation, search Dictionary.png Phase Angle Regulating Transformer Transformers that enable phase-angle control between the primary (source) and the secondary (load) side to create a phase shift between the primary side voltage and the secondary side voltage. The purpose of this phase shift is to control the real power flow through interconnected power systems.[1] Also Known As phase angle regulating transformers (PARs) Related Terms transformer, real power, smart grid References ↑ [www.smartgrid.gov/sites/default/files/pdfs/description_of_assets.pdf SmartGrid.gov 'Description of Assets'] An in LikeLike UnlikeLike You like this.Sign Up to see what your friends like. line Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Phase_Angle_Regulating_Transformer&oldid=502556"

5

Gas-Phase Molecular Dynamics  

NLE Websites -- All DOE Office Websites (Extended Search)

Gas-Phase Molecular Dynamics Gas-Phase Molecular Dynamics The Gas-Phase Molecular Dynamics Group is dedicated to developing and applying spectroscopic and theoretical tools to challenging problems in chemical physics related to reactivity, structure, dynamics and kinetics of transient species. Recent theoretical work has included advances in exact variational solution of vibrational quantum dynamics, suitable for up to five atoms in systems where large amplitude motion or multiple strongly coupled modes make simpler approximations inadequate. Other theoretical work, illustrated below, applied direct dynamics, quantum force trajectory calculations to investigate a series of reactions of the HOCO radical. The potential energy surface for the OH + CO/ H + CO2 reaction, showing two barriers (TS1 and TS2) and the deep HOCO well along the minimum energy pathway. The inset figure shows the experimental and calculated reactivity of HOCO with selected collision partners. See J.S. Francisco, J.T. Muckerman and H.-G. Yu, "HOCO radical chemistry,"

6

Effect of Load Phase Angle on Wind Turbine Blade Fatigue Damage: Preprint  

DOE Green Energy (OSTI)

This paper examines the importance of phase angle variations with respect to fatigue damage. The operating loads on a generic conventional three-bladed upwind 1.5-MW wind turbine blade were analyzed over a range of operating conditions, and an aggregate probability distribution for the actual phase angles between the in-plane (lead-lag) and out-of-plane (flap) loads was determined. Using a finite element model of a generic blade and Miner's Rule, the accumulated theoretical damage (based on axial strains) resulting from a fatigue test with variable phase angles was compared to the damage resulting from a fatigue test with a constant phase angle. The nodal damage distribution at specific blade cross-sections are compared for the constant and variable phase angle cases. The sequence effects of various phase angle progressions were also considered. For this analysis, the finite element results were processed using the nonlinear Marco-Starkey damage accumulation model. Each phase angle sequence was constrained to have the same overall phase angle distribution and the same total number of cycles but the order in which the phase angles were applied was varied.

White, D. L.; Musial, W. D.

2003-11-01T23:59:59.000Z

7

Predicting locality phases for dynamic memory optimization  

Science Conference Proceedings (OSTI)

Dynamic data, cache, and memory adaptation can significantly improve program performance when they are applied on long continuous phases of execution that have dynamic but predictable locality. To support phase-based adaptation, this paper defines the ... Keywords: Dynamic optimization, Locality analysis and optimization, Phase hierarchy, Program phase prediction, Reconfigurable architecture

Xipeng Shen; Yutao Zhong; Chen Ding

2007-07-01T23:59:59.000Z

8

Shock dynamics of phase diagrams  

E-Print Network (OSTI)

A thermodynamic phase transition denotes a drastic change of state of a physical system due to a continuous change of thermodynamic variables, as for instance pressure and temperature. The classical van der Waals equation of state is the simplest model that predicts the occurrence of a critical point associated with the gas-liquid phase transition. Nevertheless, below the critical temperature, theoretical predictions of the van der Waals theory significantly depart from the observed physical behaviour. We develop a novel approach to classical thermodynamics based on the solution of Maxwell relations for a generalised family of nonlocal entropy functions. This theory provides an exact mathematical description of discontinuities of the order parameter within the phase transition region, it explains the universal form of the equations of state and the occurrence of triple points in terms of the dynamics of nonlinear shock wave fronts.

Antonio Moro

2013-07-29T23:59:59.000Z

9

Cryogenic sample exchange NMR probe for magic angle spinning dynamic nuclear polarization  

E-Print Network (OSTI)

We describe a cryogenic sample exchange system that dramatically improves the efficiency of magic angle spinning (MAS) dynamic nuclear polarization (DNP) experiments by reducing the time required to change samples and by ...

Barnes, Alexander B.

10

Solid effect in magic angle spinning dynamic nuclear polarization  

E-Print Network (OSTI)

For over five decades, the solid effect (SE) has been heavily utilized as a mechanism for performing dynamic nuclear polarization (DNP). Nevertheless, it has not found widespread application in contemporary, high magnetic ...

Smith, Albert A.

11

Molecular Dynamics of Martenstic Phase Transitions  

Science Conference Proceedings (OSTI)

Presentation Title, Kinetics of martensitic phase transformation: Molecular Dynamics of Martenstic ... A Comparison of Coulombic and Plastic Shear Faults in Ice.

12

The two-angle model and the phase diagram for Chromatin  

E-Print Network (OSTI)

We have studied the phase diagram for chromatin within the framework of the two-angle model. Rather than improving existing models with finer details our main focus of the work is getting mathematically rigorous results on the structure, especially on the excluded volume effects and the effects on the energy due to the long-range forces and their screening. Thus we present a phase diagram for the allowed conformations and the Coulomb energies.

Philipp M. Diesinger; Dieter W. Heermann

2005-05-02T23:59:59.000Z

13

Quantum dynamics of elementary reactions in the gas phase and...  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantum dynamics of elementary reactions in the gas phase and on surfaces Quantum Dynamics of Elementary Reactions in the Gas Phase and on Surfaces Key Challenges: This research...

14

Stripe Dynamics, Global Phase Ordering and Quantum  

E-Print Network (OSTI)

By modeling the stripe phase in cuprates as spin gapped stripes coupled to the RVB liquid of preformed electron pairs, I derive the low energy effective theory of the RVB phase variable. It is found that the effect of stripe dynamics (including both longitudinal and transverse modes) leads to incipient temporal phase stiffness in the RVB liquid, which tunes a quantum phase transition toward a superconducting ground state with global phase order. Physical consequences of this quantum criticality are discussed. Typeset using REVTEX 1 I.

Criticality High; Tc Superconductors; Wenjun Zheng

2000-01-01T23:59:59.000Z

15

Dynamics of a Quantum Phase Transition  

E-Print Network (OSTI)

We present two approaches to the dynamics of a quench-induced phase transition in quantum Ising model. The first one retraces steps of the standard approach to thermodynamic second order phase transitions in the quantum setting. The second one is purely quantum, based on the Landau-Zener formula for transition probabilities in avoided level crossings. We show that the two approaches yield compatible results for the scaling of the defect density with the quench rate. We exhibit similarities between them, and comment on the insights they give into dynamics of quantum phase transitions.

Wojciech H. Zurek; Uwe Dorner; Peter Zoller

2005-03-21T23:59:59.000Z

16

Super Energy Saver Heat Pump with Dynamic Hybrid Phase Change ...  

Super Energy Saver Heat Pump with Dynamic Hybrid Phase Change Material United States Patent Application

17

Spinodal phase decomposition with dissipative fluid dynamics  

SciTech Connect

The spinodal amplification of density fluctuations is treated perturbatively within dissipative fluid dynamics including not only shear and bulk viscosity but also heat conduction, as well as a gradient term in the local pressure. The degree of spinodal amplification is calculated along specific dynamical phase trajectories and the results suggest that the effect can be greatly enhanced by tuning the collision energy so that maximum compression occurs inside the region of spinodal instability.

Randrup, J., E-mail: JRandrup@LBL.gov [Lawrence Berkeley Laboratory, Nuclear Science Division (United States)

2012-06-15T23:59:59.000Z

18

Dynamic Phase Transitions in Coupled Motor Proteins  

E-Print Network (OSTI)

The effect of interactions on dynamics of coupled motor proteins is investigated theoretically. A simple stochastic discrete model, that allows to calculate explicitly the dynamic properties of the system, is developed. It is shown that there are two dynamic regimes, depending on the interaction between the particles. For strong interactions the motor proteins move as one tight cluster, while for weak interactions there is no correlation in the motion of the proteins, and the particle separation increases steadily with time. The boundary between two dynamic phases is specified by a critical interaction that has a non-zero value only for the coupling of the asymmetric motor proteins, and it depends on the temperature and the transitions rates. At the critical interaction there is a change in a slope for the mean velocities and a discontinuity in the dispersions of the motor proteins as a function of the interaction energy.

Evgeny B. Stukalin; Anatoly B. Kolomeisky

2005-09-16T23:59:59.000Z

19

A comparison between amplitude sorting and phase-angle sorting using external respiratory measurement for 4D CT  

SciTech Connect

Respiratory motion can cause significant dose delivery errors in conformal radiation therapy for thoracic and upper abdominal tumors. Four-dimensional computed tomography (4D CT) has been proposed to provide the image data necessary to model tumor motion and consequently reduce these errors. The purpose of this work was to compare 4D CT reconstruction methods using amplitude sorting and phase angle sorting. A 16-slice CT scanner was operated in cine mode to acquire 25 scans consecutively at each couch position through the thorax. The patient underwent synchronized external respiratory measurements. The scans were sorted into 12 phases based, respectively, on the amplitude and direction (inhalation or exhalation) or on the phase angle (0-360 deg.) of the external respiratory signal. With the assumption that lung motion is largely proportional to the measured respiratory amplitude, the variation in amplitude corresponds to the variation in motion for each phase. A smaller variation in amplitude would associate with an improved reconstructed image. Air content, defined as the amount of air within the lungs, bronchi, and trachea in a 16-slice CT segment and used by our group as a surrogate for internal motion, was correlated to the respiratory amplitude and phase angle throughout the lungs. For the 35 patients who underwent quiet breathing, images (similar to those used for treatment planning) and animations (used to display respiratory motion) generated using amplitude sorting displayed fewer reconstruction artifacts than those generated using phase angle sorting. The variations in respiratory amplitude were significantly smaller (P<0.001) with amplitude sorting than those with phase angle sorting. The subdivision of the breathing cycle into more (finer) phases improved the consistency in respiratory amplitude for amplitude sorting, but not for phase angle sorting. For 33 of the 35 patients, the air content showed significantly improved (P<0.001) correlation with the respiratory amplitude than with the phase angle, suggesting a stronger relationship between internal motion and amplitude. Overall, amplitude sorting performed better than phase angle sorting for 33 of the 35 patients and equally well for two patients who were immobilized with a stereotactic body frame and an abdominal compression plate.

Lu Wei; Parikh, Parag J.; Hubenschmidt, James P.; Bradley, Jeffrey D.; Low, Daniel A. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States)

2006-08-15T23:59:59.000Z

20

Measurements of the cross-phase angle between density and electron temperature fluctuations and comparison with gyrokinetic simulations  

E-Print Network (OSTI)

This paper presents new measurements of the cross-phase angle, ?neTe [alpha n subscript n subscript e T subscript e], between long-wavelength (k??s<0.5) [k subscript theta p subscript s < 0.5)] density, n~e [n cedilla ...

White, Anne E.

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Phase dynamics and particle production in preheating  

Science Conference Proceedings (OSTI)

We study a simple model of a massive inflaton field {phi} coupled to another scalar field {chi} with interaction term g{sup 2}{phi}{sup 2}{chi}{sup 2}. We use the theory developed by Kofman et al. [L. Kofman, A. D. Linde, and A. A. Starobinsky, Phys. Rev. D 56, 3258 (1997).] for the first stage of preheating to give a full description of the dynamics of the {chi} field modes, including the behavior of the phase, in terms of the iteration of a simple family of circle maps. The parameters of this family of maps are a function of time when expansion of the Universe is taken into account. With this more detailed description, we obtain a systematic study of the efficiency of particle production as a function of the inflaton field and coupling parameters, and we find that for g < or approx. 3x10{sup -4} the broad resonance ceases during the first stage of preheating.

Charters, T. [Departamento de Mecanica/Seccao de Matematica, Instituto Superior de Engenharia de Lisboa, Rua Conselheiro Emidio Navarro, 1, P-1949-014 Lisbon (Portugal) and Centro de Fisica Teorica e Computacional da Universidade de Lisboa, Avenida Professor Gama Pinto 2, P-1649-003 Lisbon (Portugal); Nunes, A.; Mimoso, J.P. [Departamento de Fisica, Faculdade de Ciencias da Universidade de Lisboa and Centro de Fisica Teorica e Computacional da Universidade de Lisboa, Avenida Professor Gama Pinto 2, P-1649-003 Lisbon (Portugal)

2005-04-15T23:59:59.000Z

22

A Phase Field Study of Intercalation Dynamics in the Storage ...  

Science Conference Proceedings (OSTI)

Presentation Title, A Phase Field Study of Intercalation Dynamics in the Storage Electrode Materials of Li-Ion Battery. Author(s), Saswata Bhattacharya, Linyun...

23

A small angle neutron scattering investigation of the kinetics of phase separation in an Fe-27. 5 at. % Cr-5. 6 at. % Ni alloy  

Science Conference Proceedings (OSTI)

The small angle neutron scattering has been investigated in situ at 450{degree} and 500{degree}C for a polycrystalline, duplex Fe-27.5 at. % Cr-5.6 at. % Ni steel. A broad diffuse maximum in the scattering function is the signature of the {alpha}{prime}-phase formation, and this maximum is superimposed on a strong, temperature-dependent component due to critical magnetic scattering. The time dependence of the shift in the peak intensity position to lower scattering vectors and the increase in peak intensity obey power law scaling behavior. Furthermore, the structure function exhibits dynamical scaling, after about three hours annealing. It is suggested that this behavior could be utilized to predict the microstructure, and hence some of the properties, after significantly longer annealing times. 21 refs., 3 figs.

Epperson, J.E. (Argonne National Lab., IL (USA)); Rainey, V.S.; Windsor, C.G. (UKAEA Atomic Energy Research Establishment, Harwell (UK). Materials Physics and Metallurgy Div.); Hawick, K.A. (Edinburgh Univ. (UK). Dept. of Physics); Chen, H. (Illinois Univ., Urbana, IL (USA). Dept. of Materials Science and Engineering)

1990-10-01T23:59:59.000Z

24

Micromechanics of Dynamic Solid-to-Solid Phase Transformations  

Science Conference Proceedings (OSTI)

The influence of material heterogeneity on retained high-pressure phases, damage, and texture ... A Dislocation Dynamics Model of the Plastic Flow of fcc Polycrystals: ... Dynamic Contact Failure of Two Brittle Particles under Compression ... Grit on Shear Localization of HMX-Based Explosives in Drop Hammer Impact Tests.

25

Phase Separation Dynamics in Isotropic Ion-Intercalation Particles  

E-Print Network (OSTI)

Lithium-ion batteries exhibit complex nonlinear dynamics, resulting from diffusion and phase transformations coupled to ion intercalation reactions. Using the recently developed Cahn-Hilliard reaction (CHR) theory, we investigate a simple mathematical model of ion intercalation in a spherical solid nanoparticle, which predicts transitions from solid-solution radial diffusion to two-phase shrinking-core dynamics. This general approach extends previous Li-ion battery models, which either neglect phase separation or postulate a spherical shrinking-core phase boundary, by predicting phase separation only under appropriate circumstances. The effect of the applied current is captured by generalized Butler-Volmer kinetics, formulated in terms of diffusional chemical potentials, and the model consistently links the evolving concentration profile to the battery voltage. We examine sources of charge/discharge asymmetry, such as asymmetric charge transfer and surface "wetting" by ions within the solid, which can lead to...

Zeng, Yi

2013-01-01T23:59:59.000Z

26

GAS-PHASE MOLECULAR DYNAMICS: VIBRATIONAL DYNAMICS OF POLYATOMIC MOLECULES  

SciTech Connect

The goal of this research is the understanding of elementary chemical and physical processes important in the combustion of fossil fuels. Interest centers on reactions and properties of short-lived chemical intermediates. High-resolution, high-sensitivity, laser absorption methods are augmented by high-temperature, flow-tube reaction kinetics studies with mass-spectrometric sampling. These experiments provide information on the energy levels, structures and reactivity of molecular free radical species and, in turn, provide new tools for the study of energy flow and chemical bond cleavage in radicals involved in chemical systems. The experimental work is supported by theoretical studies using time-dependent quantum wavepacket calculations, which provide insight into energy flow among the vibrational modes of polyatomic molecules and interference effects in multiple-surface dynamics.

MUCKERMAN,J.T.

1999-06-09T23:59:59.000Z

27

Gas-Phase Molecular Dynamics: Vibrational Dynamics of Polyatomic Molecules  

SciTech Connect

The goal of this research is the understanding of elementary chemical and physical processes important in the combustion of fossil fuels. Interest centers on reactions and properties of short-lived chemical intermediates. High-resolution, high-sensitivity, laser absorption methods are augmented by high- temperature, flow-tube reaction kinetics studies with mass-spectrometic sampling. These experiments provide information on the energy levels, structures and reactivity of molecular free radical species and in turn, provide new tools for the study of energy flow and chemical bond cleavage in the radicals involved in chemical systems. The experimental work is supported by theoretical studies using time-dependent quantum wavepacket calculations, which provide insight into energy flow among the vibrational modes of polyatomic molecules and interference effects in multiple-surface dynamics.

Muckerman, J.T.

1999-05-21T23:59:59.000Z

28

Dynamically generated flat-band phases in optical kagome lattices  

E-Print Network (OSTI)

We suggest that a dynamically generated flat-band insulator can be realized using ultracold fermions loaded in an optical kagome lattice by depleting the mobile atoms at one edge of the lattice with a focused laser beam. Since the flat band of the kagome lattice is a high-energy one compared to the dispersive bands, this dynamically generated flat-band insulator is a population-inversion phase with no pumping required to maintain it after its formation. We also show that in a similar setup a dynamical stripe phase emerges in the flat band when two-component fermions with weakly repulsive interactions evolve in a static kagome lattice or even in the absence of interactions when the optical lattice is modulated. Given the broad variety of lattice geometries supporting frustration-induced localized states, our work opens the door to atomtronic devices utilizing geometrical effects and offers new insight on the dynamics of geometrically frustrated systems.

Gia-Wei Chern; Chih-Chun Chien; Massimiliano Di Ventra

2013-07-23T23:59:59.000Z

29

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. High-resolution spectroscopy, augmented by theoretical and computational methods, is used to investigate the structure and collision dynamics of chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry. Applications and methods development are equally important experimental components of this work.

Hall,G.E.; Sears, T.J.

2009-04-03T23:59:59.000Z

30

Gas-Phase Molecular Dynamics: Theoretical Studies In Spectroscopy and Chemical Dynamics  

Science Conference Proceedings (OSTI)

The main goal of this program is the development and application of computational methods for studying chemical reaction dynamics and molecular spectroscopy in the gas phase. We are interested in developing rigorous quantum dynamics algorithms for small polyatomic systems and in implementing approximate approaches for complex ones. Particular focus is on the dynamics and kinetics of chemical reactions and on the rovibrational spectra of species involved in combustion processes. This research also explores the potential energy surfaces of these systems of interest using state-of-the-art quantum chemistry methods, and extends them to understand some important properties of materials in condensed phases and interstellar medium as well as in combustion environments.

Yu H. G.; Muckerman, J.T.

2012-05-29T23:59:59.000Z

31

Dependency of the apparent contact angle on nonisothermal conditions  

Science Conference Proceedings (OSTI)

The dynamic behavior of liquids in partly filled containers is influenced to a large extend by the angle between the gas-liquid phase boundary and the solid container wall at the contact line. This contact angle in turn is influenced by nonisothermal conditions. In the case of a cold liquid meniscus spreading over a hot solid wall

Rolf Krahl; Jens Gerstmann; Philipp Behruzi; Eberhard Bnsch; Michael E. Dreyer

2008-01-01T23:59:59.000Z

32

Dynamic investigation of gold nanocrystal assembly using in situ grazing-incidence small angle x-ray scattering.  

SciTech Connect

Here we investigate the dynamic self-assembly pathway of ordered gold nanocrystal arrays during the self-assembly of gold nanocrystal micelles, with and without the presence of colloidal silica precursors, using grazing-incidence X-ray scattering performed at a synchrotron source. With silica precursors present, a lattice with rhombohedral symmetry is formed from the partial collapse of a face-centered cubic structure. In the absence of silica, a transient body-centered orthorhombic phase appears, which rapidly collapses into a glassy nanocrystal film. The appearance of face-centered and body-centered structures is consistent with a phase diagram for charged colloidal particles with assembly modulated via Coulomb screening.

Dunphy, D.; Fan, H.; Li, X.; Wang, J.; Brinker, C. J.; X-Ray Science Division; Univ. of New Mexico; SNL

2008-01-01T23:59:59.000Z

33

Dynamic Phase Structures in the Evolution of Conventions  

E-Print Network (OSTI)

This paper describes an agent-based model of a finite group of agents in a single population who each choose which convention to advocate, and which convention to practice. Influences or dependencies in agents choice exists in the form of guru effects and what others practice. With payoffs being dependent on cumulative rewards or actual standings in society, we illustrate the evolutionary dynamics of the phase structure of each group in the population via simulations.

Azhar, A K M; Ruzlan, M

2009-01-01T23:59:59.000Z

34

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. Chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry are investigated by high resolution spectroscopic tools. Production, reaction, and energy transfer processes are investigated by transient, double resonance, polarization and saturation spectroscopies, with an emphasis on technique development and connection with theory, as well as specific molecular properties.

Hall, G.E.

2011-05-31T23:59:59.000Z

35

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. Chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry are investigated by high resolution spectroscopic tools. Production, reaction, and energy transfer processes are investigated by transient, double resonance, polarization and saturation spectroscopies, with an emphasis on technique development and connection with theory, as well as specific molecular properties.

Hall G. E.; Goncharov, V.

2012-05-29T23:59:59.000Z

36

Gas-Phase Molecular Dynamics: Theoretical Studies in Spectroscopy and Chemical Dynamics  

SciTech Connect

The goal of this program is the development and application of computational methods for studying chemical reaction dynamics and molecular spectroscopy in the gas phase. We are interested in developing rigorous quantum dynamics algorithms for small polyatomic systems and in implementing approximate approaches for complex ones. Particular focus is on the dynamics and kinetics of chemical reactions and on the rovibrational spectra of species involved in combustion processes. This research also explores the potential energy surfaces of these systems of interest using state-of-the-art quantum chemistry methods.

Yu, H.G.; Muckerman, J.T.

2010-06-01T23:59:59.000Z

37

Gas Phase Moleculer Dynamics (GPMD) Group | Chemistry Department |  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Program Research Program The research within the Gas Phase Molecular Dynamics program spans spectroscopy, kinetics and dynamics, with input from both experiment and theory. The broad topics of recent and current focus are Development of new spectroscopic methods to probe transient molecules of importance to combustion Application of these methods to collisional dynamics and kinetics Theoretical predictions of vibrational spectra of small molecules and radicals Development and use of computational methods in reaction kinetics and dynamics, optimizing accuracy and efficiency to the size of the problem The group has long experience in the application of transient frequency modulation (FM) spectroscopy methods for probing radicals, and using this method for polarized photofragment Doppler spectroscopy and kinetics. More recently, FM applications in double resonance have been developed for spectral simplification and assignments, and for saturation recovery and transfer kinetics to study collisional energy and polarization transfer. Sub-Doppler saturation methods with FM probing have recently been applied to a variety of nuclear hyperfine structure problems in spectroscopy and dynamics. Frequency comb-stabilized diode lasers in the near infrared have been used for highly precise frequency-domain measurements of pressure broadening and line shape studies of collision effects.

38

Dynamics and Thermodynamics of a Novel Phase of NaAlH[subscript 4  

E-Print Network (OSTI)

We characterize a novel orthorhombic phase (?) of NaAlH[subscript 4], discovered using first-principles molecular dynamics, and discuss its relevance to the dehydrogenation mechanism. This phase is close in energy to the ...

Wood, Brandon C.

39

Microfluidic Platforms for on-chip Formulation and Small-Angle x-ray Analysis of the Phase Behavior of Lipid/Water Mixtures  

SciTech Connect

We present a microfluidic platform for on-chip formulation and X-ray analysis of lipidic mesophases formed upon mixing lipids and water. The platform is designed to study the effect of detergents on the phase behavior of lipid/water mixtures. The platform allows automated preparation of multiple samples of different composition from stock solutions and subsequent on-chip small-angle X-ray diffraction (SAXS) data collection. To ensure X-ray transparency of the platform we used thin layers of cyclic olefin copolymer (COC) and PDMS. The viability of the platform is demonstrated by mapping out a section of the phase diagram for lipid monoolein mixed with solutions of detergent {beta}-octylglucoside. The platform reported here is a viable alternative to the traditional method of establishing phase diagrams for lipid/solution mixtures. Compared to the conventional approach, a significantly smaller amount of sample is required for mapping phase diagrams of lipidic mesophases and samples of various compositions are prepared automatically. In ongoing work we are using these chips to rapidly determine the phase behavior of a range of lipids to establish their suitability for membrane protein crystallization, especially with respect to their sensitivity to detergent concentration.

Khvostichenko, Daria S.; Perry, Sarah L.; Kondrashkina, Elena; Guha, Sudipto; Brister, Keith; Kenis, Paul J.A. (UIUC); (NWU)

2012-03-27T23:59:59.000Z

40

Dynamic Phase Transitions In The Spin-2 Ising System Under An Oscillating Magnetic Field Within The Effective-Field Theory  

SciTech Connect

The dynamic phase transitions are studied in the spin-2 Ising model under a time-dependent oscillating magnetic field by using the effective-field theory with correlations. The effective-field dynamic equation is derived by employing the Glauber transition rates and the phases in the system are obtained by solving this dynamic equation. The nature (first- or second-order) of the dynamic phase transition is characterized by investigating the thermal behavior of the dynamic order parameter and the dynamic phase transition temperatures are obtained. The dynamic phase diagrams are presented in (T/zJ, h/zJ) plane.

Ertas, Mehmet; Keskin, Mustafa [Department of Physics, Erciyes University, 38039 Kayseri (Turkey); Deviren, Bayram [Department of Physics, Nevsehir University, 50300 Nevsehir (Turkey)

2010-12-23T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Molecular Dynamics Study of Phase Change of Water inside a Single-Walled Carbon Nanotube  

E-Print Network (OSTI)

The phase change of liquid water to ice crystal inside a single-walled carbon nanotube (SWNT) was studiedMolecular Dynamics Study of Phase Change of Water inside a Single-Walled Carbon Nanotube Shigeo phase change for various cooling rates in a SWNT with various chiralities were examined. With certain

Maruyama, Shigeo

42

Influence of the initial phase profile on the asymptotic self-similar parabolic dynamics  

E-Print Network (OSTI)

Influence of the initial phase profile on the asymptotic self-similar parabolic dynamics Christophe phase profile on the convergence towards asymptotic self-similar parabolic shape. More precisely, based on numerical simulations, we discuss the impact of an initial linear chirp and a phase shift. If the parabolic

Paris-Sud XI, Université de

43

Super energy saver heat pump with dynamic hybrid phase change ...  

The at least one outdoor heat exchanger has a phase change material in thermal communication ... Building Energy Efficiency; ... Solar Thermal; Startup America;

44

Berry's Phase, Josephson's Equation, and the Dynamics of Weak Link Superconductors and Their Vortices  

E-Print Network (OSTI)

We examine the dynamical consequences of Berry's phase for Josephson junctions, junction arrays, and their vortices. Josephson's equation and the related phase slip voltages are shown to be uneffected by Berry's phase. In an annular Josephson junction, Berry's phase is seen to generate a new current drive on a vortex. In the continuum limit, vortex dynamics in a 2D array is shown to map onto that of a 2D film. A Hall sign anomaly is expected in arrays; and the merits of arrays for studies of disorder on vortex motion is discussed.

Frank Gaitan; Subodh R. Shenoy

1995-05-19T23:59:59.000Z

45

Lattice Boltzmann Models (LBM) for Two-phase Thermo-hydro-dynamics  

NLE Websites -- All DOE Office Websites (Extended Search)

Lattice Boltzmann Models (LBM) for Two-phase Thermo-hydro-dynamics Speaker(s): Prashant Jain Date: October 15, 2009 - 12:00pm Location: 90-3122 Lattice Boltzmann Method (LBM) is...

46

Quantum dynamics in condensed phases : charge carrier mobility, decoherence, and excitation energy transfer  

E-Print Network (OSTI)

In this thesis, we develop analytical models for quantum systems and perform theoretical investigations on several dynamical processes in condensed phases. First, we study charge-carrier mobilities in organic molecular ...

Cheng, Yuan-Chung, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

47

Gas Phase Moleculer Dynamics (GPMD) Group | Chemistry Department |  

NLE Websites -- All DOE Office Websites (Extended Search)

GPMD Publications 2007 - present GPMD Publications 2007 - present H.-G. Yu, Ab initio molecular dynamics simulation of photodetachment reaction of cyclopentoxide, Chem. Phys. Lett, 441, 20 (2007). H.-G. Yu, J. T. Muckerman and J.S. Francisco, Quantum force molecular dynamics study ofthe O atoms with HOCO reaction, J. Chem. Phys. 127, 094302 (2007). M. L. Costen and G. E. Hall, Coherent and incoherent orientation and alignment of ICNphotoproducts, Phys. Chem. Chem. Phys. 9, 272-287 (2007). H.-G. Yu, G. Poggi, J.S. Francisco and J. T. Muckerman, Energetics and molecular dynamics of the reaction of HOCO with HO2 radicals, J. Chem. Phys. 129, 214307 (2008). H.-G. Yu and J.S. Francisco, Energetics and kinetics of the reaction of HOCO with hydrogen atoms, J. Chem. Phys. 128, 244315 (2008).

48

Liquid-gas phase transition in hot nuclei: correlation between dynamical and thermodynamical signals  

E-Print Network (OSTI)

The dynamics and thermodynamics of phase transition in hot nuclei are studied through experimental results on multifragmentation of heavy systems (A$geq$200) formed in central heavy ion collisions. Different signals indicative of a phase transition studied in the INDRA collaboration are presented and their consistency is stressed.

M. F. Rivet; B. Borderie; R. Bougault; P. Dsesquelles; E. Galichet; B. Guiot; N. Le Neindre; M. Parlog; G. Tabacaru; J. P. Wieleczko; the INDRA Collaboration

2005-01-12T23:59:59.000Z

49

Dynamic Transition Theory and its Application to Gas-Liquid Phase Transitions  

E-Print Network (OSTI)

Dynamic Transition Theory and its Application to Gas-Liquid Phase Transitions Tian Ma, Shouhong close links to the physics. In return the theory is applied to the physical problems. 2 #12;liquid gas #12;Objective: To study the types and the mechanisms of liquid-gas transitions. The phases correspond

Wang, Shouhong

50

Capillary Dynamics of Elastic?Wave?Enhanced Two?Phase Flow in Porous Media  

Science Conference Proceedings (OSTI)

Elastic waves may enhance two?phase flow in porous media. We investigate the role and dynamics of capillary forces during the enhancement process. We present a theory that allows us to estimate the response of trapped nonwetting phase blobs to variable frequency excitation. According to this theory capillary trapped oil blobs may exhibit resonance

Markus Hilpert; Chunyan Guo; Joseph Katz

2006-01-01T23:59:59.000Z

51

A heuristic method to minimise the chattering problem in dynamic mathematical two-phase flow models  

Science Conference Proceedings (OSTI)

This paper introduces the chattering problem in dynamic mathematical two-phase flow models. The real system object of study is also introduced, the DISS test facility, a parabolic-trough solar power plant using as heat transfer fluid the steam-water ... Keywords: Chattering, Heuristic methods, Modelling and simulation, Parabolic-trough solar power plant, Two-phase flow, Zeno phenomenon

J. Bonilla; L. J. Yebra; S. Dormido

2011-09-01T23:59:59.000Z

52

Dynamic High Pressure Measurements and Molecular Dynamics Simulations of Phase Changes and Vibrational Dynamics in Molecular Solids  

E-Print Network (OSTI)

rate on the phase transitions of Ice VI 17,18 and Ice VII.for the phase transitions of water ? Ice VI and Ice VI ? Iceobserve the phase transitions of water ? Ice VI and Ice VI ?

Rice, Andrew Patrick

2011-01-01T23:59:59.000Z

53

Alternating-phase focusing: A model to study nonlinear dynamics  

Science Conference Proceedings (OSTI)

We discuss a new model to study alternating-phase focusing (APF). Our approach is based on representing the accelerating electric field with a continuous phase modulated traveling wave. The resulting nonlinear equations of motion can be solved analytically to predict the regions of stable APF motion. We also identify the key parameters which adequately describe the physics of APF. The model is believed to be applicable to low-{beta} ion linacs with short independently-controlled superconducting cavities being developed at ANL.

Sagalovsky, L.; Delayen, J.R.

1992-09-01T23:59:59.000Z

54

Alternating-phase focusing: A model to study nonlinear dynamics  

SciTech Connect

We discuss a new model to study alternating-phase focusing (APF). Our approach is based on representing the accelerating electric field with a continuous phase modulated traveling wave. The resulting nonlinear equations of motion can be solved analytically to predict the regions of stable APF motion. We also identify the key parameters which adequately describe the physics of APF. The model is believed to be applicable to low-{beta} ion linacs with short independently-controlled superconducting cavities being developed at ANL.

Sagalovsky, L.; Delayen, J.R.

1992-01-01T23:59:59.000Z

55

Gas Phase Moleculer Dynamics (GPMD) Group | Chemistry Department |  

NLE Websites -- All DOE Office Websites (Extended Search)

Group Members Group Members Greg Hall (Group Leader) Chemical dynamics of unimolecular and bimolecular reactions. High resolution spectroscopic probes of collisional energy transfer processes. Elastic and inelastic interactions responsible for pressure broadening, saturation relaxation and depolarization. Non-adiabatic reactions and multiple surface interactions. Vector correlations and angular momentum polarization probes of chemical dynamics. Applied laser spectroscopy. Trevor Sears (PI) Use of frequency comb techniques for precision spectroscopic measurements in chemical systems. Development of new high resolution and high sensitivity spectroscopic techniques. Free radical spectroscopy relevant to combustion chemistry. Characterization of collisional phenomena and their effects on spectroscopic lineshapes, pressure broadening and sub-Doppler measurements. Hyperfine spectroscopy of 207PbF for potential e-EDM measurements

56

Optimal pulse control of dynamic systems in the shock phase  

Science Conference Proceedings (OSTI)

For minimization and maximization of the kinetic energy of a body hitting a fixed visco-elastic obstacle with the energy calculated at the instant of body detachment from the obstacle, the optimal control laws in the impact phase were obtained.

A. A. Galyaev

2006-01-01T23:59:59.000Z

57

Grain boundary dynamics in stripe phases of non potential systems  

E-Print Network (OSTI)

We describe numerical solutions of two non potential models of pattern formation in nonequilibrium systems to address the motion and decay of grain boundaries separating domains of stripe configurations of different orientations. We first address wavenumber selection because of the boundary, and possible decay modes when the periodicity of the stripe phases is different from the selected wavenumber for a stationary boundary. We discuss several decay modes including long wavelength undulations of the moving boundary as well as the formation of localized defects and their subsequent motion. We find three different regimes as a function of the distance to the stripe phase threshold and initial wavenumber, and then correlate these findings with domain morphology during domain coarsening in a large aspect ratio configuration.

Zhi-Feng Huang; Jorge Vinals

2006-12-11T23:59:59.000Z

58

A new modeling approach of STLF with integrated dynamics mechanism and based on the fusion of dynamic optimal neighbor phase points and ICNN  

Science Conference Proceedings (OSTI)

Based on the time evolution similarity principle of the topological neighbor phase points in the Phase Space Reconstruction (PSR), a new modeling approach of Short-Term Load Forecasting (STLF) with integrated dynamics mechanism and based on the fusion ...

Zhisheng Zhang; Yaming Sun; Shiying Zhang

2006-05-01T23:59:59.000Z

59

Gas Phase Moleculer Dynamics (GPMD) Group | Chemistry Department |  

NLE Websites -- All DOE Office Websites (Extended Search)

Instrumentation Instrumentation The GPMD experimental laboratories will relocate into newly renovated space in the historic BNL Chemistry Building in fall 2013. The major instrumentation for spectroscopy, kinetics and chemical dynamics studies includes two CW Ti:sapphire ring laser systems, several Lambda Physik excimer lasers, a Nd:Yag-pumped dye laser system, a 355 nm pumped high-resolution OPO system, numerous external-cavity diode lasers operating as tunable cw sources in the near infrared region, and a mode-locked fiber ring laser with amplifier and supercontinuum generation in the 1-2 micron region. A commercial 1.5 micron self-referenced frequency comb and associated external cavity diode lasers are located in the Sears laboratory in the Chemistry Department of Stony Brook University.

60

Quantum dynamics of elementary reactions in the gas phase and on surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantum Quantum dynamics of elementary reactions in the gas phase and on surfaces Quantum Dynamics of Elementary Reactions in the Gas Phase and on Surfaces Key Challenges: This research addresses several important dynamics issues in elementary chemical reactions. One of the major obstacles in such studies is the quantum nature of the reactions, where the zero-point energy, mode selectivity, dynamical resonances, non-adiabatic transitions, and tunneling play an important role. The calculations are very challenging because of the large number of quantum states involved, and because of the large number of partial waves. The work required development of new methods and new, highly-efficient codes to calculate the total and state-resolved reaction probabilities. Numerically, the calculations are based on sparse

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61

Performance monitoring for new phase dynamic optimization of instruction dispatch cluster configuration  

DOE Patents (OSTI)

In a processor having multiple clusters which operate in parallel, the number of clusters in use can be varied dynamically. At the start of each program phase, the configuration option for an interval is run to determine the optimal configuration, which is used until the next phase change is detected. The optimum instruction interval is determined by starting with a minimum interval and doubling it until a low stability factor is reached.

Balasubramonian, Rajeev (Sandy, UT); Dwarkadas, Sandhya (Rochester, NY); Albonesi, David (Ithaca, NY)

2012-01-24T23:59:59.000Z

62

Width bifurcation and dynamical phase transitions in open quantum systems  

E-Print Network (OSTI)

The states of an open quantum system are coupled via the environment of scattering wavefunctions. The complex coupling coefficients $\\omega$ between system and environment arise from the principal value integral and the residuum. At high level density where the resonance states overlap, the dynamics of the system is determined by exceptional points. At these points, the eigenvalues of two states are equal and the corresponding eigenfunctions are linearly dependent. It is shown in the present paper that Im$(\\omega)$ and Re$(\\omega)$ influence the system properties differently in the surrounding of exceptional points. Controlling the system by a parameter, the eigenvalues avoid crossing in energy near an exceptional point under the influence of Re$(\\omega)$ in a similar manner as it is well known from discrete states. Im$(\\omega)$ however leads to width bifurcation and finally (when the system is coupled to one channel, i.e. to a common continuum of scattering wavefunctions), to a splitting of the system into two parts with different characteristic time scales. Physically, the system is stabilized by this splitting since the lifetimes of most ($N-1$) states are longer than before while that of only one state is shorter. In the cross section the short-lived state appears as a background term in high-resolution experiments. The wavefunctions of the long-lived states are mixed in those of the original ones in a comparably large parameter range. Numerical results for the eigenvalues and eigenfunctions are shown for $N=2, ~4$ and 10 states coupled mostly to 1 channel.

Hichem Eleuch; Ingrid Rotter

2013-03-26T23:59:59.000Z

63

DYNAMIC MODELING STRATEGY FOR FLOW REGIME TRANSITION IN GAS-LIQUID TWO-PHASE FLOWS  

SciTech Connect

In modeling gas-liquid two-phase flows, the concept of flow regime has been used to characterize the global interfacial structure of the flows. Nearly all constitutive relations that provide closures to the interfacial transfers in two-phase flow models, such as the two-fluid model, are often flow regime dependent. Currently, the determination of the flow regimes is primarily based on flow regime maps or transition criteria, which are developed for steady-state, fully-developed flows and widely applied in nuclear reactor system safety analysis codes, such as RELAP5. As two-phase flows are observed to be dynamic in nature (fully-developed two-phase flows generally do not exist in real applications), it is of importance to model the flow regime transition dynamically for more accurate predictions of two-phase flows. The present work aims to develop a dynamic modeling strategy for determining flow regimes in gas-liquid two-phase flows through the introduction of interfacial area transport equations (IATEs) within the framework of a two-fluid model. The IATE is a transport equation that models the interfacial area concentration by considering the creation and destruction of the interfacial area, such as the fluid particle (bubble or liquid droplet) disintegration, boiling and evaporation; and fluid particle coalescence and condensation, respectively. For the flow regimes beyond bubbly flows, a two-group IATE has been proposed, in which bubbles are divided into two groups based on their size and shape (which are correlated), namely small bubbles and large bubbles. A preliminary approach to dynamically identifying the flow regimes is provided, in which discriminators are based on the predicted information, such as the void fraction and interfacial area concentration of small bubble and large bubble groups. This method is expected to be applied to computer codes to improve their predictive capabilities of gas-liquid two-phase flows, in particular for the applications in which flow regime transition occurs.

X. Wang; X. Sun; H. Zhao

2011-09-01T23:59:59.000Z

64

Tunneling dynamics and phase transition of a Bose-Fermi mixture in a double well  

Science Conference Proceedings (OSTI)

The coherent nonlinear tunneling dynamics of a boson-fermion mixture in a double-well potential is studied in this paper. Four types of phase are found for the mixture. The first one is two species localizing in different potential wells. The second one is two species coexisting in the same well. The third one is two species equally populated in two wells. The fourth one is one species equally populated in two wells while the other species is in one well. The phase transitions among these four states have been investigated. The interspecies and intraspecies interactions as well as bosonic and fermionic numbers can dramatically affect these phase transitions.

Qi Pengtang; Duan Wenshan [Department of Physics, Northwest Normal University, Lanzhou, 730070 (China)

2011-09-15T23:59:59.000Z

65

Dynamic van der Waals Theory of Two-Phase Fluids in Heat Flow Akira Onuki  

E-Print Network (OSTI)

Dynamic van der Waals Theory of Two-Phase Fluids in Heat Flow Akira Onuki Department of Physics as a functional of the order parameter and the energy density. Let us consider one-component fluids, where-component fluids the effect is drastically altered due to latent heat generation or absorption at the interface [12

66

Nuclear liquid-gas phase transition studied with antisymmetrized molecular dynamics  

E-Print Network (OSTI)

The nuclear liquid-gas phase transition of the system in ideal thermal equilibrium is studied with antisymmetrized molecular dynamics. The time evolution of a many-nucleon system confined in a container is solved for a long time to get a microcanonical ensemble of a given energy and volume. The temperature and the pressure are extracted from this ensemble and the caloric curves are constructed. The present work is the first time that a microscopic dynamical model which describes nuclear multifragmentation reactions well is directly applied to get the nuclear caloric curve. The obtained constant pressure caloric curves clearly show the characteristic feature of the liquid-gas phase transition, namely negative heat capacity (backbending), which is expected for the phase transition in finite systems.

Takuya Furuta; Akira Ono

2003-05-19T23:59:59.000Z

67

Dynamic fracture behavior of Ti-6Al-4V alloy with various stabilities of [beta] phase  

Science Conference Proceedings (OSTI)

The effect of stability of the body-centered cubic (bcc) [beta] phase on the dynamic fracture behavior of Ti-6Al-4V alloy at room temperature and 77 K has been studied. The presence of a highly unstable [beta] phase in the quenched alloy leads to a decrease in both the dynamic fracture toughness and the crack propagation energy, and this decrease becomes more pronounced when test temperature is reduced to 77 K. Somewhat improved fracture characteristics were obtained by applying anneal procedure to receive a fully stable [beta] phase. The highest fracture toughness as well as the greatest crack propagation resistance were observed in the air-cooled grade, where the lattice parameter of the bcc phase was intermediate between those pertaining to quenched and annealed Ti-6Al-4V alloys. The effect is attributed to the vanadium content in the [beta] phase, which is sufficiently high to suppress deformation-induced transformation. On the other hand, the V content should be low enough to retard ductile-brittle transition, typical for the bcc metals at cryogenic temperatures. As a result, marked toughening can be achieved, so that the lowest application temperature of high-strength titanium alloys containing the bcc phase can be decreased significantly.

Akmoulin, I.A.; Niinomi, M.; Kobayashi, T. (Toyohashi Univ. of Technology (Japan). Dept. of Production Systems Engineering)

1994-08-01T23:59:59.000Z

68

Measurement techniques for local and global fluid dynamic quantities in two and three phase systems  

SciTech Connect

This report presents a critical review of the methods available for assessing the fluid dynamic parameters in large industrial two and three phase bubble column and slurry bubble column reactors operated at high pressure and temperature. The physical principles behind various methods are explained, and the basic design of the instrumentation needed to implement each measurement principle is discussed. Fluid dynamic properties of interest are: gas, liquid and solids holdup and their axial and radial distribution as well as the velocity distribution of the two (bubble column) or three phases (slurry bubble column). This information on operating pilot plant and plant reactors is essential to verify the computational fluid dynamic codes as well as scale-up rules used in reactor design. Without such information extensive and costly scale-up to large reactors that exploit syngas chemistries, and other reactors in production of fuels and chemicals, cannot be avoided. In this report, available measurement techniques for evaluation of global and local phase holdups, instantaneous and average phase velocities and for the determination of bubble sizes in gas-liquid and gas-liquid-solid systems are reviewed. Advantages and disadvantages of various techniques are discussed. Particular emphasis is placed on identifying methods that can be employed on large scale, thick wall, high pressure and high temperature reactors used in the manufacture of fuels and chemicals from synthesis gas and its derivatives.

Kumar, S.; Dudukovic, M.P. [Washington Univ., St. Louis, MO (United States). Chemical Reaction Engineering Lab.; Toseland, B.A. [Air Products and Chemicals, Inc., Lehigh Valley, PA (United States)

1996-03-01T23:59:59.000Z

69

Rare-event trajectory ensemble analysis reveals metastable dynamical phases in lattice proteins  

E-Print Network (OSTI)

We explore the dynamical large-deviations of a lattice heteropolymer model of a protein by means of path sampling of trajectories. We uncover the existence of non-equilibrium dynamical phase-transitions in ensembles of trajectories between active and inactive dynamical phases, whose nature depends on properties of the interaction potential. When the full heterogeneity of interactions due to the amino-acid sequence is preserved, as in a fully interacting model or in a heterogeneous version of the G\\={o} model where only native interactions are considered, the transition is between the equilibrium native state and a highly native but kinetically trapped state. In contrast, for the homogeneous G\\={o} model, where there is a single native energy and the sequence plays no role, the dynamical transition is a direct consequence of the static bi-stability between unfolded and native states. In the heterogeneous case the native-active and native-inactive states, despite their static similarity, have widely varying dynamical properties, and the transition between them occurs even in lattice proteins whose sequences are designed to make them optimal folders.

Antonia S. J. S. Mey; Phillip L. Geissler; Juan P. Garrahan

2013-05-24T23:59:59.000Z

70

A Dynamic Two-Phase Flow Model of Proton Exchange Membrane Fuel Cells  

E-Print Network (OSTI)

A dynamic two phase flow model for proton exchange membrane (PEM) fuel cells is presented. The two dimensional along-the-channel model includes the two phase flow of water (gaseous and liquid) in the porous diffusion layers and in the catalyst layers, as well as the transport of the species in the gas phase. Moreover, proton and water transport in the membrane and the oxygen reduction reaction in the cathodic catalyst layer is accounted for. The discretisation of the resulting flow equations is done by a mixed finite element approach. Based on this the transport equations for the species in each phase are discretised by a finite volume scheme. The coupled mixed finite element/finite volume approach gives the spatially resolved water and gas saturation and the species concentrations. In order to describe the charge transport in the fuel cell the Poisson equations for the electrons and protons are solved by using Galerkin finite element schemes.

Karsten Khn; K. Khn; Mario Ohlberger; Jrgen O. Schumacher; C. Ziegler; R. Klfkorn; Karsten Khn Ab; Mario Ohlberger Cd; Jrgen O. Schumacher A; Christoph Ziegler; Robert Klfkorn C

2003-01-01T23:59:59.000Z

71

Molecular Dynamics Simulation of Phase-Change of Water inside a SWNT Shigeo Maruyama, Tatsuto Kimura and Yasuhiro Igarashi  

E-Print Network (OSTI)

, Bunkyo-ku, Tokyo 113-8656, Japan The phase change of liquid water to ice crystal inside a singleMolecular Dynamics Simulation of Phase-Change of Water inside a SWNT Shigeo Maruyama, Tatsuto, the carbon atoms were cooled at the constant heat-removal rate. The phase change phenomena with various rates

Maruyama, Shigeo

72

Liquid-gas phase transition in finite nuclei within Fermionic Molecular Dynamics  

E-Print Network (OSTI)

Within Fermionic Molecular Dynamics (FMD) a quantal nuclear system with only 16 nucleons shows a clearly visible liquid-gas phase transition. The FMD model is an approximation to the many-body problem which describes the system by antisymmetrized many-body states in which each nucleon is occupying a Gaussian shaped time-dependent wave-packet. The statistical ensemble is obtained by time averaging.

H. Feldmeier; J. Schnack

1998-06-02T23:59:59.000Z

73

Gas-phase and Solution-phase Peptide Conformations Studied by Ion Mobility-mass Spectrometry and Molecular Dynamics Simulations  

E-Print Network (OSTI)

Ion mobility spectrometry (IMS) separates ions on the basis of ion-neutral collision cross-sections (CCS, [omega]), which are determined by the geometry or conformation of the ions. The size-based IM separation can be extended to distinguish conformers that have different shapes in cases where shape differences influence the accessible surface area of the molecule. In recent years, IM has rapidly evolved as a structural characterization technique, which has applied on various structural biology problems. In this work, IMS is combined with molecular dynamics simulation (MDS), specially the integrated tempering sampling molecular dynamics simulation (ITS-MDS) to explore the gas-phase conformation space of two molecular systems (i) protonated tryptophan zipper 1 (trpzip1) ions and its six derivatives (ii) alkali metal ion (Na, K and Cs) adducts of gramicidin A (GA). The structural distributions obtained from ITS-MDS are compared well with results obtained from matrix-assisted laser desorption ionization-ion mobility-mass spectrometry (MALDI-IM-MS) for trpzip 1 series and electrospray ionization-ion mobility-mass spectrometry (ESI-IM-MS) for alkali metal ion adducts of GA. Furthermore, the solvent dependence on conformational preferences of the GA dimer is investigated using a combination of mass spectrometry techniques, viz. ESI-IM-MS and hydrogen/deuterium exchange (HDX)-MS, and MDS. The IM experiments reveal three distinct gramicidin A species, detected as the sodium ion adduct ions, [2GA + 2Na]?, and the equilibrium abundances of the dimer ions varies with solvent polarity. The solution phase conformations are assigned as the parallel and anti-parallel [beta]-helix dimer, and the anti-parallel dimer is the preferred conformation in non-polar organic solvent. The calculated CCS profiles by ITS-MDS agree very well with the experimentally measured CCS profiles, which underscore the utility of the method for determining candidate structures as well as the relative abundances of the candidate structures. The benefit of combining ion mobility measurements with solution-phase H/D exchange is allowing identifications and detail analysis of the solution-phase subgroup conformations, which cannot be uncovered by one method alone.

Chen, Liuxi

2012-08-01T23:59:59.000Z

74

Liquid phase fluid dynamic (methanol) run in the LaPorte alternative fuels development unit  

DOE Green Energy (OSTI)

A fluid dynamic study was successfully completed in a bubble column at DOE's Alternative Fuels Development Unit (AFDU) in LaPorte, Texas. Significant fluid dynamic information was gathered at pilot scale during three weeks of Liquid Phase Methanol (LPMEOJP) operations in June 1995. In addition to the usual nuclear density and temperature measurements, unique differential pressure data were collected using Sandia's high-speed data acquisition system to gain insight on flow regime characteristics and bubble size distribution. Statistical analysis of the fluctuations in the pressure data suggests that the column was being operated in the churn turbulent regime at most of the velocities considered. Dynamic gas disengagement experiments showed a different behavior than seen in low-pressure, cold-flow work. Operation with a superficial gas velocity of 1.2 ft/sec was achieved during this run, with stable fluid dynamics and catalyst performance. Improvements included for catalyst activation in the design of the Clean Coal III LPMEOH{trademark} plant at Kingsport, Tennessee, were also confirmed. In addition, an alternate catalyst was demonstrated for LPMEOH{trademark}.

Bharat L. Bhatt

1997-05-01T23:59:59.000Z

75

TMS320F2812 DSP controller for dynamic voltage restorer (DVR) application for improving of a three phase inverter  

Science Conference Proceedings (OSTI)

This paper discusses a control technique improvement of a three-phase inverter using TMS320F2812 DSP controller for Dynamic Voltage Restorer (DVR) applications. The output of the inverter is then connected to a voltage grid via a second order filter ... Keywords: TMS320F2812 DSP, dynamic voltage restorer (DVR), filter, inverters, total harmonic distortion (THD)

R. Omar; N. A. Rahim

2010-07-01T23:59:59.000Z

76

Large-scale molecular dynamics simulations of shock-induced plasticity, phase transformations, and detonation  

SciTech Connect

Modern computers enable routine multimillion-atom molecular dynamics simulations of shock propagation in solids using realistic interatomic potentials, and offer a direct insight into the atomistic processes underlying plasticity, phase transformations, and the detonation of energetic materials. Past, present, and prospects for future simulations will be discussed in the context of prototypical systems for each of these three classes of problems. Initial samples ranging from perfect single crystals, to those with specific isolated defects, to full-fledged polycrystalline materials will be considered.

Germann, T. C. (Timothy C.)

2001-06-01T23:59:59.000Z

77

Hierarchical Classifier-Regression Ensemble for Multi-phase Non-linear Dynamic System Response Prediction: Application to Climate Analysis  

Science Conference Proceedings (OSTI)

A dynamic physical system often undergoes phase transitions in response to fluctuations induced on system parameters. For example, hurricane activity is the climate system's response initiated by a liquid-vapor phase transition associated with non-linearly ... Keywords: Anomaly detection, Rainfall prediction, Tropical cyclone prediction, spatio-temporal data mining, regression, classification

Doel L. Gonzalez, Zhengzhang Chen, Isaac K. Tetteh, Tatdow Pansombut, Fredrick Semazzi, Vipin Kumar, Anatoli Melechko, Nagiza F. Samatova

2012-12-01T23:59:59.000Z

78

Computational Particle Dynamic Simulations on Multicore Processors (CPDMu) Final Report ?? Phase I  

SciTech Connect

Statement of Problem - Department of Energy has many legacy codes for simulation of computational particle dynamics and computational fluid dynamics applications that are designed to run on sequential processors and are not easily parallelized. Emerging high-performance computing architectures employ massively parallel multicore architectures (e.g., graphics processing units) to increase throughput. Parallelization of legacy simulation codes is a high priority, to achieve compatibility, efficiency, accuracy, and extensibility. General Statement of Solution - A legacy simulation application designed for implementation on mainly-sequential processors has been represented as a graph G. Mathematical transformations, applied to G, produce a graph representation {und G} for a high-performance architecture. Key computational and data movement kernels of the application were analyzed/optimized for parallel execution using the mapping G {yields} {und G}, which can be performed semi-automatically. This approach is widely applicable to many types of high-performance computing systems, such as graphics processing units or clusters comprised of nodes that contain one or more such units. Phase I Accomplishments - Phase I research decomposed/profiled computational particle dynamics simulation code for rocket fuel combustion into low and high computational cost regions (respectively, mainly sequential and mainly parallel kernels), with analysis of space and time complexity. Using the research team's expertise in algorithm-to-architecture mappings, the high-cost kernels were transformed, parallelized, and implemented on Nvidia Fermi GPUs. Measured speedups (GPU with respect to single-core CPU) were approximately 20-32X for realistic model parameters, without final optimization. Error analysis showed no loss of computational accuracy. Commercial Applications and Other Benefits - The proposed research will constitute a breakthrough in solution of problems related to efficient parallel computation of particle and fluid dynamics simulations. These problems occur throughout DOE, military and commercial sectors: the potential payoff is high. We plan to license or sell the solution to contractors for military and domestic applications such as disaster simulation (aerodynamic and hydrodynamic), Government agencies (hydrological and environmental simulations), and medical applications (e.g., in tomographic image reconstruction). Keywords - High-performance Computing, Graphic Processing Unit, Fluid/Particle Simulation. Summary for Members of Congress - Department of Energy has many simulation codes that must compute faster, to be effective. The Phase I research parallelized particle/fluid simulations for rocket combustion, for high-performance computing systems.

Mark S. Schmalz

2011-07-24T23:59:59.000Z

79

Effects of ice number concentration on dynamics of a shallow mixed-phase stratiform cloud  

SciTech Connect

Previous modeling studies have shown a high sensitivity of simulated properties of mixed-phase clouds to ice number concentration, Ni, with many models losing their ability to maintain the liquid phase as Ni increases. Although models differ widely at what Ni the mixed-phase cloud becomes unstable, the transition from a mixed-phase to an ice only cloud in many cases occurs over a narrow range of ice concentration. To gain better understanding of this non-linear model behavior, in this study, we analyze simulations of a mixed-phase stratiform Artic cloud observed on 26 April 2008 during recent Indirect and Semi-Direct Aerosol Campaign (ISDAC). The BASE simulation, in which Ni is constrained to match the measured value, produces a long-lived cloud in a quasi steady state similar to that observed. The simulation without the ice (NO_ICE) produces a comparable but slightly thicker cloud because more moisture is kept in the mixed layer due to lack of precipitation. When Ni is quadrupled relative to BASE (HI_ICE), the cloud starts loosing liquid water almost immediately and the liquid water path is reduced by half in less than two hours. The changes in liquid water are accompanied by corresponding reduction in the radiative cooling of the layer and a slow down in the vertical mixing, confirming the important role of interactions among microphysics, radiation and dynamics in this type of clouds. Deviations of BASE and HI_ICE from NO_ICE are used to explore the linearity of the model response to variation in Ni. It is shown that at early stages, changes in liquid and ice water as well as in radiative cooling/heating rates are proportional to the Ni change, while changes in the vertical buoyancy flux are qualitatively different in HI_ICE compared to BASE. Thus, while the positive feedback between the liquid water path and radiative cooling of the cloud layer is essential for glaciation of the cloud at higher Ni, the non-linear (with respect to Ni) reduction in positive buoyancy flux within and below the liquid cloud layer emerges as the process that influences the initial response of the mixed layer dynamics to the appearance of ice and subsequently determines the sustainability of liquid water in the cloud in this case.

Ovchinnikov, Mikhail; Korolev, Alexei; Fan, Jiwen

2011-09-17T23:59:59.000Z

80

First principles analysis of lattice dynamics for Fe-based superconductors and entropically-stabilized phases  

Science Conference Proceedings (OSTI)

Modern calculations are becoming an essential, complementary tool to inelastic x-ray scattering studies, where x-rays are scattered inelastically to resolve meV phonons. Calculations of the inelastic structure factor for any value of Q assist in both planning the experiment and analyzing the results. Moreover, differences between the measured data and theoretical calculations help identify important new physics driving the properties of novel correlated systems. We have used such calculations to better and more e#14;ciently measure the phonon dispersion and elastic constants of several iron pnictide superconductors. This dissertation describes calculations and measurements at room temperature in the tetragonal phase of CaFe{sub 2}As{sub 2} and LaFeAsO. In both cases, spin-polarized calculations imposing the antiferromagnetic order present in the low-temperature orthorhombic phase dramatically improves the agreement between theory and experiment. This is discussed in terms of the strong antiferromagnetic correlations that are known to persist in the tetragonal phase. In addition, we discuss a relatively new approach called self-consistent ab initio lattice dynamics (SCAILD), which goes beyond the harmonic approximation to include phonon-phonon interactions and produce a temperature-dependent phonon dispersion. We used this technique to study the HCP to BCC transition in beryllium.

Hahn, Steven

2012-07-20T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Direct observation of dynamic surface acoustic wave controlled carrier injection into single quantum posts using phase-resolved optical spectroscopy  

E-Print Network (OSTI)

A versatile stroboscopic technique based on active phase-locking of a surface acoustic wave to picosecond laser pulses is used to monitor dynamic acoustoelectric effects. Time-integrated multi-channel detection is applied to probe the modulation of the emission of a quantum well for different frequencies of the surface acoustic wave. For quantum posts we resolve dynamically controlled generation of neutral and charged excitons and preferential injection of holes into localized states within the nanostructure.

Vlk, S; Schlein, F J R; Truong, T A; Kim, H; Petroff, P M; Wixforth, A; Krenner, H J

2010-01-01T23:59:59.000Z

82

Direct observation of dynamic surface acoustic wave controlled carrier injection into single quantum posts using phase-resolved optical spectroscopy  

E-Print Network (OSTI)

A versatile stroboscopic technique based on active phase-locking of a surface acoustic wave to picosecond laser pulses is used to monitor dynamic acoustoelectric effects. Time-integrated multi-channel detection is applied to probe the modulation of the emission of a quantum well for different frequencies of the surface acoustic wave. For quantum posts we resolve dynamically controlled generation of neutral and charged excitons and preferential injection of holes into localized states within the nanostructure.

S. Vlk; F. Knall; F. J. R. Schlein; T. A. Truong; H. Kim; P. M. Petroff; A. Wixforth; H. J. Krenner

2010-11-08T23:59:59.000Z

83

Enhancement of two-phase flow images obtained using dynamic neutron radiography  

E-Print Network (OSTI)

Though both film and video radiographic image techniques are available in neutron radiography, radiographic video cameras are commonly used to capture the dynamic flow patterns in a rapid sequence of images. These images may be useful to verify two-phase flow models in small diameter flow channels. An initial series of real-time neutron radiography experiments were performed at the Texas A&M University System, Texas Engineering Experiment Station, Nuclear Science Center Reactor (NSCR) to evaluate the effectiveness of various image enhancement algorithms and procedures, beneficial for visualization of two-phase water and air flow regimes through small diameter metal flow channels. After evaluating these initial images, research was conducted to improve the images coming from the camera and to evaluate the particular forms of enhancement. Contrast enhancement and smoothing filters were applied to improve the ability to visualize the flow regimes. Tracking algorithms were applied to gather flow information in the form of vector flow plots. Finally, Monte Carlo analysis was performed to test the possibility of gathering three dimensional data from two dimensional images.

Johns, Russell Craig

1995-01-01T23:59:59.000Z

84

Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization  

SciTech Connect

We show that dynamic nuclear polarization (DNP) can be used to enhance NMR signals of 13C and 29Si nuclei located in mesoporous organic/inorganic hybrid materials, at several hundreds of nanometers from stable radicals (TOTAPOL) trapped in the surrounding frozen disordered water. The approach is demonstrated using mesoporous silica nanoparticles (MSN), functionalized with 3-(N-phenylureido)propyl (PUP) groups, filled with the surfactant cetyltrimethylammonium bromide (CTAB). The DNP-enhanced proton magnetization is transported into the mesopores via 1H1H spin diffusion and transferred to rare spins by cross-polarization, yielding signal enhancements ?on/off of around 8. When the CTAB molecules are extracted, so that the radicals can enter the mesopores, the enhancements increase to ?on/off ? 30 for both nuclei. A quantitative analysis of the signal enhancements in MSN with and without surfactant is based on a one-dimensional proton spin diffusion model. The effect of solvent deuteration is also investigated.

Lafon, Olivier [Universite de Lille Nord de France; Thankamony, Aany S. Lilly [Universite de Lille Nord de France; Kokayashi, Takeshi [Ames Laboratory; Carnevale, Diego [Ecole Polytechnique Federale de Lausanne; Vitzthum, Veronika [Ecole Polytechnique Federale de Lausanne; Slowing, Igor I. [Ames Laboratory; Kandel, Kapil [Ames Laboratory; Vezin, Herve [Universite de Lille Nord de France; Amoureux, Jean-Paul [Universite de Lille Nord de France; Bodenhausen, Geoffrey [Ecole Polytechnique Federale de Lausanne; Pruski, Marek [Ames Laboratory

2012-12-21T23:59:59.000Z

85

Research on the SPLL based single phase voltage sag detection technique  

Science Conference Proceedings (OSTI)

The drop of voltage amplitude and the jump of phase angle are two important parameters of the voltage sag. The design of Dynamic Voltage Restorer (DVR) compensation voltage with voltage sag parameters is discussed and a single-phase sag parameter detection ... Keywords: SPLL, detection, single-phase, voltage sag

Xie Yue; Chen Le; Sun Jian; Gong Xu

2008-04-01T23:59:59.000Z

86

Metallic phase-change materials for solar dynamic energy storage systems  

DOE Green Energy (OSTI)

Solar (thermal) dynamic power systems for satellites require a heat storage system that is capable of operating the engine during eclipse. The conventional approach to this thermal storage problem is to use the latent heat of fluoride salts, which would melt during insolation and freeze during eclipse. Although candidate fluorides have large heats of fusion per unit mass, their poor thermal conductivity limits the rate at which energy can be transferred to and from the storage device. System performance is further limited by the high parasitic mass of the superalloy canisters needed to contain the salt. This report describes a new thermal storage system in which the phase-change material (PCM) is a metal (typically germanium) contained in modular graphite canisters. These modules exhibit good thermal conductivity and low parasitic mass, and they are physically and chemically stable. Prototype modules have survived over 600 melt/freeze cycles without degradation. Advanced concepts to further improve performance are described. These concepts include the selection of ternary eutectic alloys to provide a wider range of useful melting temperatures and the use of infiltration to control the location of liquid alloy and to compensate for differences in thermal expansion. 13 refs., 18 figs.

Lauf, R.J.; Hamby, C. Jr.

1990-12-01T23:59:59.000Z

87

Phase matching of high order harmonic generation using dynamic phase modulation caused by a non-collinear modulation pulse  

DOE Patents (OSTI)

Phase matching high harmonic generation (HHG) uses a single, long duration non-collinear modulating pulse intersecting the driving pulse. A femtosecond driving pulse is focused into an HHG medium (such as a noble gas) to cause high-harmonic generation (HHG), for example in the X-ray region of the spectrum, via electrons separating from and recombining with gas atoms. A non-collinear pulse intersects the driving pulse within the gas, and modulates the field seen by the electrons while separated from their atoms. The modulating pulse is low power and long duration, and its frequency and amplitude is chosen to improve HHG phase matching by increasing the areas of constructive interference between the driving pulse and the HHG, relative to the areas of destructive interference.

Cohen, Oren (Boulder, CO); Kapteyn, Henry C. (Boulder, CO); Mumane, Margaret M. (Boulder, CO)

2010-02-16T23:59:59.000Z

88

Geometric phase effects in low-energy dynamics near conical intersections: A study of the multidimensional linear vibronic coupling model  

E-Print Network (OSTI)

In molecular systems containing conical intersections (CIs), a nontrivial geometric phase (GP) appears in the nuclear and electronic wave-functions in the adiabatic representation. We study GP effects in nuclear dynamics of an N-dimensional linear vibronic coupling (LVC) model. The main impact of GP on low-energy nuclear dynamics is reduction of population transfer between the local minima of the LVC lower energy surface. For the LVC model, we proposed an isometric coordinate transformation that confines non-adiabatic effects within a two-dimensional subsystem interacting with an N-2 dimensional environment. Since environmental modes do not couple electronic states, all GP effects originate from nuclear dynamics within the subsystem. We explored when the GP affects nuclear dynamics of the isolated subsystem, and how the subsystem-environment interaction can interfere with GP effects. Comparing quantum dynamics with and without GP allowed us to devise simple rules to determine significance of the GP for nuclear dynamics in this model.

Loic Joubert-Doriol; Ilya G. Ryabinkin; Artur F. Izmaylov

2013-10-10T23:59:59.000Z

89

Computational fluid dynamics modeling of two-phase flow in a BWR fuel assembly. Final CRADA Report.  

Science Conference Proceedings (OSTI)

A direct numerical simulation capability for two-phase flows with heat transfer in complex geometries can considerably reduce the hardware development cycle, facilitate the optimization and reduce the costs of testing of various industrial facilities, such as nuclear power plants, steam generators, steam condensers, liquid cooling systems, heat exchangers, distillers, and boilers. Specifically, the phenomena occurring in a two-phase coolant flow in a BWR (Boiling Water Reactor) fuel assembly include coolant phase changes and multiple flow regimes which directly influence the coolant interaction with fuel assembly and, ultimately, the reactor performance. Traditionally, the best analysis tools for this purpose of two-phase flow phenomena inside the BWR fuel assembly have been the sub-channel codes. However, the resolution of these codes is too coarse for analyzing the detailed intra-assembly flow patterns, such as flow around a spacer element. Advanced CFD (Computational Fluid Dynamics) codes provide a potential for detailed 3D simulations of coolant flow inside a fuel assembly, including flow around a spacer element using more fundamental physical models of flow regimes and phase interactions than sub-channel codes. Such models can extend the code applicability to a wider range of situations, which is highly important for increasing the efficiency and to prevent accidents.

Tentner, A.; Nuclear Engineering Division

2009-10-13T23:59:59.000Z

90

Measurement techniques for local and global fluid dynamic quantities in two and three phase systems  

Science Conference Proceedings (OSTI)

Available measurement techniques for evaluation of global and local phase holdups, instantaneous and average phase velocities and for the determination of bubble sizes in gas-liquid and gas-liquid-solid systems are reviewed. Advantages and disadvantages of various techniques are discussed. Particular emphasis is placed on identifying methods that can be employed on large scale, thick wall, high pressure and high temperature reactors used in the manufacture of fuels and chemicals from synthesis gas and its derivatives.

Kumar, S.; Dudukovic, M.P.; Toseland, B.A.

1998-01-01T23:59:59.000Z

91

In-situ Monitoring of Dynamic Phenomena during Solidification and Phase Transformation Processing  

Science Conference Proceedings (OSTI)

The purpose of this project is to: (1) Directly observe phase transformations and microstructure evolution using proton (and synchrotron x-ray) radiography and tomography; (2) Constrain phase-field models for microstructure evolution; (3) Experimentally control microstructure evolution during processing to enable co-design; and (4) Advance toward the MaRIE vision. Understand microstructure evolution and chemical segregation during solidification {yields} solid-state transformations in Pu-Ga.

Clarke, Amy J. [Los Alamos National Laboratory; Cooley, Jason C. [Los Alamos National Laboratory; Morris, Christopher [Los Alamos National Laboratory; Merrill, Frank E. [Los Alamos National Laboratory; Hollander, Brian J. [Los Alamos National Laboratory; Mariam, Fesseha G. [Los Alamos National Laboratory; Patterson, Brian M. [Los Alamos National Laboratory; Imhoff, Seth D. [Los Alamos National Laboratory; Lee, Wah Keat [Brookhaven National Lab; Fezzaa, Kamel [Argonne National Lab; Deriy, Alex [Argonne NationalLbaoratory; Tucker, Tim J. [Los Alamos National Laboratory; Clarke, Kester D. [Los Alamos National Laboratory; Field, Robert D. [Los Alamos National Laboratory; Thoma, Dan J. [Los Alamos National Laboratory; Teter, David F. [Los Alamos National Laboratory; Beard, Timothy V. [Los Alamos National Laboratory; Hudson, Richard W. [Los Alamos National Laboratory; Freibert, Franz J. [Los Alamos National Laboratory; Korzekwa, Deniece R. [Los Alamos National Laboratory; Farrow, Adam M. [Los Alamos National Laboratory; Cross, Carl E. [Los Alamos National Laboratory; Mihaila, Bogdan [Los Alamos National Laboratory; Lookman, Turab [Los Alamos National Laboratory; Hunter, Abigail [Los Alamos National Laboratory; Choudhury, Samrat [Los Alamos National Laboratory; Karma, Alain [Northeastern University; Ott, Thomas J. Jr. [Los Alamos National Laboratory; Barker, Martha R. [Los Alamos National Laboratory; O'Neill, Finian [Former MST-6 Summer Student; Hill, Joshua [Former MST-6 Summer Student; Emigh, Megan G. [Los Alamos National Laboratory

2012-07-30T23:59:59.000Z

92

Geological formation - drill string dynamic interaction finite-element program (GEODYN). Phase 1. Theoretical description  

DOE Green Energy (OSTI)

The Theoretical Description for the GEODYN interactive finite-element computer program is presented. The program is capable of performing the analysis of the three-dimensional transient dynamic response of a Polycrystalline Diamond Compact Bit-Bit Sub arising from the intermittent contact of the bit with the downhole rock formations. The program accommodates nonlinear, time-dependent, loading and boundary conditions.

Baird, J.A.; Apostal, M.C.; Rotelli, R.L. Jr.; Tinianow, M.A.; Wormley, D.N.

1984-06-01T23:59:59.000Z

93

Phase 1 user instruction manual. A geological formation - drill string dynamic interaction finite element program (GEODYN)  

DOE Green Energy (OSTI)

User instructions for the GEODYN Interactive Finite Element Computer Program are presented. The program is capable of performing the analysis of the three-dimensional transient dynamic response of a Polycrystalline Diamond Compact Bit - Bit Sub arising from the intermittent contact of the bit with the downhole rock formations. The program accommodates non-linear, time dependent, loading and boundary conditions.

Tinianow, M.A.; Rotelli, R.L. Jr.; Baird, J.A.

1984-06-01T23:59:59.000Z

94

Power System Dynamic Security Analysis Using Artificial Intelligence Systems: Phase 1 -- Feasibility Evaluation  

Science Conference Proceedings (OSTI)

On-line transient stability analysis, using actual system conditions, will allow more realistic stability limits. The result will be improved economy through increased transfers across the transmission grid. This feasibility evaluation explores ways of using artificial intelligence and other techniques to solve the computational problems associated with dynamic security analysis.

1994-04-26T23:59:59.000Z

95

Angle performance on optima MDxt  

Science Conference Proceedings (OSTI)

Angle control on medium current implanters is important due to the high angle-sensitivity of typical medium current implants, such as halo implants. On the Optima MDxt, beam-to-wafer angles are controlled in both the horizontal and vertical directions. In the horizontal direction, the beam angle is measured through six narrow slits, and any angle adjustment is made by electrostatically steering the beam, while cross-wafer beam parallelism is adjusted by changing the focus of the electrostatic parallelizing lens (P-lens). In the vertical direction, the beam angle is measured through a high aspect ratio mask, and any angle adjustment is made by slightly tilting the wafer platen prior to implant. A variety of tests were run to measure the accuracy and repeatability of Optima MDxt's angle control. SIMS profiles of a high energy, channeling sensitive condition show both the cross-wafer angle uniformity, along with the small-angle resolution of the system. Angle repeatability was quantified by running a channeling sensitive implant as a regular monitor over a seven month period and measuring the sheet resistance-to-angle sensitivity. Even though crystal cut error was not controlled for in this case, when attributing all Rs variation to angle changes, the overall angle repeatability was measured as 0.16 Degree-Sign (1{sigma}). A separate angle repeatability test involved running a series of V-curves tests over a four month period using low crystal cut wafers selected from the same boule. The results of this test showed the angle repeatability to be <0.1 Degree-Sign (1{sigma}).

David, Jonathan; Kamenitsa, Dennis [Axcelis Technologies, Inc., 108 Cherry Hill Dr, Beverly, MA 01915 (United States)

2012-11-06T23:59:59.000Z

96

Dynamic Heat Flow Measurements to Study the Distribution of Phase-Change Material in an Insulation Matrix  

DOE Green Energy (OSTI)

Phase change materials (PCMs) are used in building envelopes in many forms. The PCMs may be encased in discrete pouches or containers, or they may be distributed within another medium, such as in a board or within a loose fill product. In addition, most PCM products are blends containing fire retardants and chemical stabilizers. However, the current test method to measure the dynamic characteristics of PCMs, the differential scanning calorimeter (DSC), requires specimens that are relatively uniform and very small. Considering the limitations of DSC test results when applied to more complex PCM building envelope applications, we developed a combined experimental analytical protocol to determine the amount of phase-change energy actually available to provide thermal storage. This paper presents this new methodology for performing dynamic heat flow analysis of complex PCM-enhanced building materials. The experimental analytical protocol uses a conventional heat-flow apparatus and three-dimensional (3-D), finite-difference modeling. Based upon results from this methodology, ORNL researchers developed a simplified one-dimensional (1-D) model that can be easily used in whole-building simulations. This paper describes this methodology as applied to an insulation assembly containing a complex array of PCM pouches.

Kosny, Jan [ORNL; Stovall, Therese K [ORNL; Yarbrough, David W [ORNL

2010-01-01T23:59:59.000Z

97

Proper input phase-space filling for accurate beam-dynamics codes  

Science Conference Proceedings (OSTI)

In the future, more attention will be required concerning the filling of the input phase space used by particle-simulation codes. The prospect of greatly improved particle-tracking codes implies that code input distributions must be accurate models of real input distributions. Much of present simulation work is done using artificial phase-space distributions (K-V, waterbag, etc.). Real beams can differ dramatically from such ideal input. We have already developed a method for deriving code input distributions from measurements. This paper addresses the problem of determining the number of pseudoparticles needed to model the measured distribution properly.

Boicourt, G.P.; Vasquez, M.C.

1986-01-01T23:59:59.000Z

98

Sedimentation of a two-dimensional colloidal mixture exhibiting liquid-liquid and gas-liquid phase separation: a dynamical density functional theory study  

E-Print Network (OSTI)

We present dynamical density functional theory results for the time evolution of the density distribution of a sedimenting model two-dimensional binary mixture of colloids. The interplay between the bulk phase behaviour of the mixture, its interfacial properties at the confining walls, and the gravitational field gives rise to a rich variety of equilibrium and non-equilibrium morphologies. In the fluid state, the system exhibits both liquid-liquid and gas-liquid phase separation. As the system sediments, the phase separation significantly affects the dynamics and we explore situations where the final state is a coexistence of up to three different phases. Solving the dynamical equations in two-dimensions, we find that in certain situations the final density profiles of the two species have a symmetry that is different from that of the external potentials, which is perhaps surprising, given the statistical mechanics origin of the theory. The paper concludes with a discussion on this.

Alexandr Malijevsky; Andrew J. Archer

2013-09-17T23:59:59.000Z

99

The nuclear liquid-gas phase transition within Fermionic Molecular Dynamics  

E-Print Network (OSTI)

The time evolution of excited nuclei, which are in equilibrium with the surrounding vapour, is investigated. It is shown that the finite nuclear systems undergo a first oder phase transition. The caloric curve is presented for excited Oxygen, Magnesium, Aluminum and Calcium and the critical temperature is estimated for Oxygen.

J. Schnack; H. Feldmeier

1997-03-19T23:59:59.000Z

100

Determination of Optical-Field Ionization Dynamics in Plasmas through the Direct Measurement of the Optical Phase Change  

DOE Green Energy (OSTI)

This is the final report of a three-year Laboratory Directed Research and Development (LDRD) Project at Los Alamos National Laboratory (LANL). The detailed dynamics of an atom in a strong laser field is rich in both interesting physics and potential applications. The goal of this project was to develop a technique for characterizing high-field laser-plasma interactions with femtosecond resolution based on the direct measurement of the phase change of an optical pulse. The authors developed the technique of Multi-pulse Interferometric Frequency Resolved Optical Gating (MI-FROG), which recovers (to all orders) the phase difference between pumped and unpumped probe pulses, enabling the determination of sub-pulsewidth time-resolved phase and frequency shifts impressed by a pump pulse on a weak probe pulse. Using MI-FROG, the authors obtained the first quantitative measurements of high-field ionization rates in noble gases and diatomic molecules. They obtained agreement between the measured ionization rates an d those calculated for the noble gases and diatomic nitrogen and hydrogen using a one-dimensional fluid model and rates derived from tunneling theory. However, much higher rates are measured for diatomic oxygen than predicted by tunneling theory calculations.

Taylor, A.J.; Omenetto, G.; Rodriguez, G.; Siders, C.W.; Siders, J.L.W.; Downer, C.

1999-07-16T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Heat transfer and fluid dynamics of air-water two-phase flow in micro-channels  

SciTech Connect

Heat transfer, pressure drop, and void fraction were simultaneously measured for upward heated air-water non-boiling two-phase flow in 0.51 mm ID tube to investigate thermo-hydro dynamic characteristics of two-phase flow in micro-channels. At low liquid superficial velocity j{sub l} frictional pressure drop agreed with Mishima-Hibiki's correlation, whereas agreed with Chisholm-Laird's correlation at relatively high j{sub l}. Void fraction was lower than the homogeneous model and conventional empirical correlations. To interpret the decrease of void fraction with decrease of tube diameter, a relation among the void fraction, pressure gradient and tube diameter was derived. Heat transfer coefficient fairly agreed with the data for 1.03 and 2.01 mm ID tubes when j{sub l} was relatively high. But it became lower than that for larger diameter tubes when j{sub l} was low. Analogy between heat transfer and frictional pressure drop was proved to hold roughly for the two-phase flow in micro-channel. But satisfactory relation was not obtained under the condition of low liquid superficial velocity. (author)

Kaji, Masuo; Sawai, Toru; Kagi, Yosuke [Department of Mechanical Engineering, School of Biology-Oriented Science and Technology, Kinki University, 930 Nishi-mitani, Kinokawa, Wakayama 649-6493 (Japan); Ueda, Tadanobu [Toyota Central R and D Laboratory, Incorporated, 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan)

2010-05-15T23:59:59.000Z

102

Super energy saver heat pump with dynamic hybrid phase change material  

Science Conference Proceedings (OSTI)

A heat pump has a refrigerant loop, a compressor in fluid communication with the refrigerant loop, at least one indoor heat exchanger in fluid communication with the refrigerant loop, and at least one outdoor heat exchanger in fluid communication with the refrigerant loop. The at least one outdoor heat exchanger has a phase change material in thermal communication with the refrigerant loop and in fluid communication with an outdoor environment. Other systems, devices, and methods are described.

Ally, Moonis Raza (Oak Ridge, TN); Tomlinson, John Jager (Knoxville, TN); Rice, Clifford Keith (Clinton, TN)

2010-07-20T23:59:59.000Z

103

Ab-initio study of structure and dynamical properties of crystalline ice. Phase Transitions 78 179  

E-Print Network (OSTI)

We investigated the structural and dynamical properties of a tetrahedrally coordinated crystalline ice from first principles based on density functional theory within the generalized gradient approximation with the projected augmented wave method. First, we report the structural behaviour of ice at finite temperatures based on the analysis of radial distribution functions obtained by molecular dynamics simulations. The results show how the ordering of the hydrogen bonding breaks down in the tetrahedral network of ice with entropy increase in agreement with the neutron diffraction data. We also calculated the phonon spectra of ice in a 3 1 1 supercell by using the direct method. So far, due to the direct method used in this calculation, the phonon spectra is obtained without taking into account the effect of polarization arising from dipole-dipole interactions of water molecules which is expected to yield the splitting of longitudinal and transverse optic modes at the ?-point. The calculated longitudinal acoustic velocities from the initial slopes of the acoustic mode is in a reasonable agreement with the neutron scatering data. The analysis of the vibrational density of states shows the existence of a boson peak at low energy of translational region a characteristic common to amorphous systems.

W. A. Adeagbo; A. Zayak; P. Entel

2005-01-01T23:59:59.000Z

104

Imaging of cardiac perfusion of free-breathing small animals using dynamic phase-correlated micro-CT  

SciTech Connect

Purpose:Mouse models of cardiac diseases have proven to be a valuable tool in preclinical research. The high cardiac and respiratory rates of free breathing mice prohibit conventional in vivo cardiac perfusion studies using computed tomography even if gating methods are applied. This makes a sacrification of the animals unavoidable and only allows for the application of ex vivo methods. Methods: To overcome this issue the authors propose a low dose scan protocol and an associated reconstruction algorithm that allows for in vivo imaging of cardiac perfusion and associated processes that are retrospectively synchronized to the respiratory and cardiac motion of the animal. The scan protocol consists of repetitive injections of contrast media within several consecutive scans while the ECG, respiratory motion, and timestamp of contrast injection are recorded and synchronized to the acquired projections. The iterative reconstruction algorithm employs a six-dimensional edge-preserving filter to provide low-noise, motion artifact-free images of the animal examined using the authors' low dose scan protocol. Results: The reconstructions obtained show that the complete temporal bolus evolution can be visualized and quantified in any desired combination of cardiac and respiratory phase including reperfusion phases. The proposed reconstruction method thereby keeps the administered radiation dose at a minimum and thus reduces metabolic inference to the animal allowing for longitudinal studies. Conclusions: The authors' low dose scan protocol and phase-correlated dynamic reconstruction algorithm allow for an easy and effective way to visualize phase-correlated perfusion processes in routine laboratory studies using free-breathing mice.

Sawall, Stefan; Kuntz, Jan; Socher, Michaela; Knaup, Michael; Hess, Andreas; Bartling, Soenke; Kachelriess, Marc [Institute of Medical Physics, Friedrich-Alexander-University (FAU) Erlangen-Nuernberg, 91052 Erlangen, Germany and Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Animal Laboratory Services Core Facility, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Institute of Medical Physics, Friedrich-Alexander-University (FAU) Erlangen-Nuernberg, 91052 Erlangen (Germany); Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-University (FAU) Erlangen-Nuernberg, 91052 Erlangen (Germany); Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Institute of Medical Physics, Friedrich-Alexander-University (FAU) Erlangen-Nuernberg, 91052 Erlangen, Germany and Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

2012-12-15T23:59:59.000Z

105

Dynamic  

Office of Legacy Management (LM)

Dynamic Dynamic , and Static , Res.ponse of the Government Oil Shale Mine at ' , . , Rifle, Colorado, to the Rulison Event. , . ; . . DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. p ( y c - - a 2-1 0 -4- REPORT AT (29-2) 914 USBM 1 0 0 1 UNITED STATES DEPARTMENT O F THE I NTERIOR BUREAU OF MINES e s.09 P. L. R U S S E L L RESEARCH D l RECTOR Februory 2, lB7O DYNAMIC AND STATIC RESPONSE 'OF THE GOVERNMENT OIL SHALE MINE A T RIFLE, COLORADO, T O THE, RULISON EVENT ORDER FROM CFSTl A S ~ B ~ &J C / This page intentionally left blank CONTENTS Page . . . . . . . . . . . . . . . . . . . . . . . . . H i s t o r i c . a l Des c r i p t i o n 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Summary 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Introduction 3

106

Dynamic light scattering study on phase separation of a protein-water mixture: Application on cold cataract development in the ocular lens  

E-Print Network (OSTI)

We present a detailed dynamic light scattering study on the phase separation in the ocular lens emerging during cold cataract development. Cold cataract is a phase separation effect that proceeds via spinodal decomposition of the lens cytoplasm with cooling. Intensity auto-correlation functions of the lens protein content are analyzed with the aid of two methods providing information on the populations and dynamics of the scattering elements associated with cold cataract. It is found that the temperature dependence of many measurable parameters changes appreciably at the characteristic temperature ~16+1 oC which is associated with the onset of cold cataract. Extending the temperature range of this work to previously inaccessible regimes, i.e. well below the phase separation or coexistence curve at Tcc, we have been able to accurately determine the temperature dependence of the collective and self-diffusion coefficient of proteins near the spinodal. The analysis showed that the dynamics of proteins bears some resemblance to the dynamics of structural glasses where the apparent activation energy for particle diffusion increases below Tcc indicating a highly cooperative motion. Application of ideas developed for studying the critical dynamics of binary protein/solvent mixtures, as well as the use of a modified Arrhenius equation, enabled us to estimate the spinodal temperature Tsp of the lens nucleus. The applicability of dynamic light scattering as a non-invasive, early-diagnostic tool for ocular diseases is also demonstrated in the light of the findings of the present paper.

V. Petta; N. Pharmakakis; G. N. Papatheodorou; S. N. Yannopoulos

2008-06-11T23:59:59.000Z

107

Irreversible Aging Dynamics and Generic Phase Behavior of Aqueous Suspensions of Laponite  

E-Print Network (OSTI)

In this work we study the aging behavior of aqueous suspension of Laponite having 2.8 weight % concentration using rheological tools. At various salt concentration all the samples demonstrate orientational order when observed using crossed polarizers. In rheological experiments we observe inherent irreversibility in the aging dynamics which forces the system not to rejuvenate to the same state in the shear melting experiment carried out at a later date since preparation. The extensive rheological experiments carried out as a function of time elapsed since preparation demonstrate the self similar trend in the aging behavior irrespective of the concentration of salt. We observe that the exploration of the low energy states as a function of aging time is only kinetically affected by the presence of salt. We estimate that the energy barrier to attain the low energy states decreases linearly with increase in the concentration of salt. The observed superposition of all the elapsed time and the salt concentration dependent data suggests that the aging that occurs in low salt concentration systems over a very long period is qualitatively similar to the aging behavior observed in systems with high salt concentration over a shorter period.

A. Shahin; Yogesh M. Joshi

2010-01-26T23:59:59.000Z

108

Phase-only shaped laser pulses in optimal control theory: Application to indirect photofragmentation dynamics in the weak-field limit  

SciTech Connect

We implement phase-only shaped laser pulses within quantum optimal control theory for laser-molecule interaction. This approach is applied to the indirect photofragmentation dynamics of NaI in the weak-field limit. It is shown that optimized phase-modulated pulses with a fixed frequency distribution can substantially modify transient dissociation probabilities as well as the momentum distribution associated with the relative motion of Na and I.

Shu, Chuan-Cun; Henriksen, Niels E. [Department of Chemistry, Building 207, Technical University of Denmark, DK-2800, Kongens Lyngby (Denmark)

2012-01-28T23:59:59.000Z

109

Dynamics  

NLE Websites -- All DOE Office Websites (Extended Search)

Hydration Hydration Water on Rutile Studied by Backscattering Neutron Spectroscopy and Molecular Dynamics Simulation E. Mamontov,* ,† D. J. Wesolowski, ‡ L. Vlcek, § P. T. Cummings, §,| J. Rosenqvist, ‡ W. Wang, ⊥ and D. R. Cole ‡ Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6473, Chemical Sciences DiVision, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110, Department of Chemical Engineering, Vanderbilt UniVersity, NashVille, Tennessee 37235-1604, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6496, and EnVironmental Sciences DiVision, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6036 ReceiVed: December 20, 2007; ReVised Manuscript ReceiVed: June 4, 2008 The high energy resolution, coupled with the wide dynamic range, of the new backscattering

110

Spinning angle optical calibration apparatus  

DOE Patents (OSTI)

An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.

Beer, Stephen K. (Morgantown, WV); Pratt, II, Harold R. (Morgantown, WV)

1991-01-01T23:59:59.000Z

111

Spinning angle optical calibration apparatus  

DOE Patents (OSTI)

An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting and accurate reproducing of spinning magic angles in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the magic angle of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning magic angle of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position. 2 figs.

Beer, S.K.; Pratt, H.R. II.

1989-09-12T23:59:59.000Z

112

Extending the boundaries of the usage of NMR chemical shifts in deciphering biomolecular structure and dynamics  

E-Print Network (OSTI)

Extending the Boundaries of the Usage of NMR Chemical Shifts in Deciphering Biomolecular Structure and Dynamics Aleksandr B. Sahakyan A thesis submitted for the degree of Doctor of Philosophy Department of Chemistry University of Cambridge Darwin 9... ? and ? dihedral angles. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 1.3 The gas-phase optimised structures of the selected representative conformations of Ace-Ala-Nme with the fixed ? and ? angles and the corresponding secondary...

Sahakyan, Aleksandr B.

2012-07-03T23:59:59.000Z

113

GAS PHASE MOLECULAR DYNAMICS  

SciTech Connect

The goal of this research is the understanding of elementary chemical and physical processes important in the combustion of fossil fuels. Interest centers on reactions involving short-lived chemical intermediates and their properties. High-resolution, high-sensitivity, laser absorption methods are augmented by high temperature flow-tube reaction kinetics studies with mass-spectrometric sampling. These experiments provide information on the energy levels, structures and reactivity of molecular free radical species and, in turn, provide new tools for the study of energy flow and chemical bond cleavage in the radicals in chemical systems. The experimental work is supported by theoretical and computational work using time-dependent quantum wavepacket calculations that provide insights into energy flow between the vibrational modes of the molecule. The work of group members Fockenberg and Muckerman is described in separate abstracts of this volume.

SEARS,T.J.; HALL,G.E.; PRESES,J.M.; WESTON,R.E.,JR.

1999-06-09T23:59:59.000Z

114

Gas Phase Molecular Dynamics  

Science Conference Proceedings (OSTI)

The goal of this research is the understanding of elementary chemical and physical processes important in the combustion of fossil fuels. Interest centers on reactions involving short-lived chemical intermediates and their properties. High-resolution high-sensitivity laser absorption methods are augmented by high temperature flow-tube reaction kinetics studies with mass spectrometric sampling. These experiments provide information on the energy levels, structures and reactivity of molecular flee radical species and, in turn, provide new tools for the study of energy flow and chemical bond cleavage in the radicals in chemical systems. The experimental work is supported by theoretical and computational work using time-dependent quantum wavepacket calculations that provide insights into energy flow between the vibrational modes of the molecule.

Hall, G.E.; Prrese, J.M.; Sears, T.J.; Weston, R.E.

1999-05-21T23:59:59.000Z

115

Phase effect on flow control for dielectric barrier plasma actuators  

SciTech Connect

Active control of flow has a wide range of applications. Specifically, mitigation of detachment due to the weakly ionized gas flow past a flat plate at an angle of attack is studied using two asymmetric sets of electrode pairs kept at a phase lag. The equations governing the dynamics of electrons, helium ions, and neutrals are solved self-consistently with charge-Poisson equation. The electrodynamic forces produced by two actuators largely depend on the relative phase between the potentials applied to rf electrodes and distance between them. A suitable phase and an optimum distance exist between two actuators for effective separation control.

Singh, K. P.; Roy, Subrata [Computational Plasma Dynamics Laboratory, Mechanical Engineering, Kettering University, Flint, Michigan 48504 (United States)

2006-07-03T23:59:59.000Z

116

Level-dynamic approach to the excited spectra of the Jahn-Teller model - kink-train lattice and 'glassy' quantum phase  

E-Print Network (OSTI)

The dynamics of excited phonon spectra of the Exe Jahn-Teller (hereafter, JT) model mapped onto the generalized Calogero-Moser (gCM) gas of pseudoparticles implies a complex interplay between nonlinearity and fluctuations of quasiparticle trajectories. A broad crossover appears in a pseudotime (interaction strength) between the initial oscillator region and the nonlinear region of the kink-train lattice as a superlattice of the kink-antikink gCM trajectories. The local nonlinear fluctuations, nuclei (droplets) of the growing kink phase arise at the crossover, forming a new intermediate droplet "glassy" phase as a precursor of the kink phase. The "glassy" phase is related to a broad maximum in the entropy of the probability distributions of pseudoparticle accelerations, or level curvatures. The kink-train lattice phase with multiple kink-antikink collisions is stabilised by long-range correlations when approaching a semiclassical limit. A series of bifurcations of nearest-level spacings were recognised as signatures of pre-chaotic behaviour at the quantum level in the kink phase. Statistical characteristics can be seen to confirm the coexistence within all of the spectra of both regularity and chaoticity to a varying extent (nonuniversality). Regions are observed within which one of the phases is dominant.

E. Majernikova; S. Shpyrko

2007-11-27T23:59:59.000Z

117

Low Wind Speed Technology Phase II: Offshore Floating Wind Turbine Concepts: Fully Coupled Dynamic Response Simulations; Massachusetts Institute of Technology  

SciTech Connect

This fact sheet describes a subcontract with Massachusetts Institute of Technology to study dynamic response simulations to evaluate floating platform concepts for offshore wind turbines.

2006-03-01T23:59:59.000Z

118

Definition: Angle of incidence | Open Energy Information  

Open Energy Info (EERE)

Angle of incidence Angle of incidence Jump to: navigation, search Dictionary.png Angle of incidence In reference to solar energy systems: the angle a ray of sun makes with a line perpendicular to a surface; for example, a surface directly facing the sun has an angle of incidence of zero, and a surface parallel to the sun (such as a sunrise striking a horizontal rooftop) has an angle of incidence of 90°. Sunlight with an incident angle of 90° tends to be absorbed, while lower angles tend to be reflected.[1][2] View on Wikipedia Wikipedia Definition Angle of incidence is a measure of deviation of something from "straight on", for example: in the approach of a ray to a surface, or the angle at which the wing or horizontal tail of an airplane is installed on the fuselage, measured relative to the axis of the fuselage.

119

Novel crystal phase in suspensions of hard ellipsoids  

E-Print Network (OSTI)

We present a computer simulation study on the crystalline phases of hard ellipsoids of revolution. For aspect ratios greater than or equal to 3 the previously suggested stretched-fcc phase [D. Frenkel and B. M. Mulder, Mol. Phys. 55, 1171 (1985)] is replaced by a novel crystalline phase. Its unit cell contains two ellipsoids with unequal orientations. The lattice is simple monoclinic. The angle of inclination of the lattice, beta, is a very soft degree of freedom, while the two right angles are stiff. For one particular value of beta, the close-packed version of this crystal is a specimen of the family of superdense packings recently reported [Donev et al., Phys. Rev. Lett. 92, 255506 (2004)]. These results are relevant for studies of nucleation and glassy dynamics of colloidal suspensions of ellipsoids.

Patrick Pfleiderer; Tanja Schilling

2006-12-06T23:59:59.000Z

120

Thermodynamics and Phase Diagrams  

Science Conference Proceedings (OSTI)

...of two-phase fields meet also is limited by thermodynamics. That is, the angle must be such that the extension of each beyond the point of intersection projects into a two-phase field, rather than a one-phase

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121

Building Energy Software Tools Directory : SunAngle Professional...  

NLE Websites -- All DOE Office Websites (Extended Search)

SunAngle Professional Suite Back to Tool SunAngle Excel screenshot SunAngle Java screenshot SunAngle technical manual...

122

Solar Pilot Plant, Phase I. Preliminary design report. Volume II, Book 3. Dynamic simulation model and computer program descriptions. CDRL item 2. [SPP dynamics simulation program  

DOE Green Energy (OSTI)

The mathematical models and computer program comprising the SPP Dynamic Simulation are described. The SPP Dynamic Simulation is a computerized model representing the time-varying performance characteristics of the SPP. The model incorporates all the principal components of the pilot plant. Time-dependent direct normal solar insulation, as corrupted by simulated cloud passages, is transformed into absorbed radiant power by actions of the heliostat field and enclosed receiver cavity. The absorbed power then drives the steam generator model to produce superheated steam for the turbine and/or thermal storage subsystems. The thermal storage subsystem can, in turn, also produce steam for the turbine. The turbine using the steam flow energy produces the mechanical shaft power necessary for the generator to convert it to electrical power. This electrical power is subsequently transmitted to a transmission grid system. Exhaust steam from the turbine is condensed, reheated, deaerated, and pressurized by pumps for return as feedwater to the thermal storage and/or steam generator. A master control/instrumentation system is utilized to coordinate the various plant operations. The master controller reacts to plant operator demands and control settings to effect the desired output response. The SPP Dynamic Simulation Computer program is written in FORTRAN language. Various input options (e.g., insolation values, load demands, initial pressures/temperatures/flows) are permitted. Plant performance may be monitored via computer printout or computer generated plots. The remainder of this document describes the detailed pilot plant dynamic model, the basis for this simulation, and the utilization of this simulation to obtain analytical plant performance results.

None

1977-05-01T23:59:59.000Z

123

Depletion-induced structure and dynamics in bimodal colloidal suspensions.  

Science Conference Proceedings (OSTI)

Combined small angle x-ray scattering and x-ray photon correlation spectroscopy studies of moderately concentrated bimodal hard-sphere colloidal suspensions in the fluid phase show that depletion-induced demixing introduces spatially heterogeneous dynamics with two distinct time scales. The adhesive nature, as well as the mobility, of the large particles is determined by the level of interaction within the monomodal domains. This interaction is driven by osmotic forces, which are governed by the relative concentration of the constituents.

Sikorski, M.; Sandy, A. R.; Narayanan, S. (X-Ray Science Division)

2011-05-03T23:59:59.000Z

124

Structure and Phase Transitions of Monolayers of Intermediate-length n-alkanes on Graphite Studied by Neutron Diffraction and Molecular Dynamics Simulation  

Science Conference Proceedings (OSTI)

We present evidence from neutron diffraction measurements and molecular dynamics (MD) simulations of three different monolayer phases of the intermediate-length alkanes tetracosane (n-C(24)H(50) denoted as C24) and dotriacontane (n-C(32)H(66) denoted as C32) adsorbed on a graphite basal-plane surface. Our measurements indicate that the two monolayer films differ principally in the transition temperatures between phases. At the lowest temperatures, both C24 and C32 form a crystalline monolayer phase with a rectangular-centered (RC) structure. The two sublattices of the RC structure each consists of parallel rows of molecules in their all-trans conformation aligned with their long axis parallel to the surface and forming so-called lamellas of width approximately equal to the all-trans length of the molecule. The RC structure is uniaxially commensurate with the graphite surface in its [110] direction such that the distance between molecular rows in a lamella is 4.26 A=sqrt[3a(g)], where a(g)=2.46 A is the lattice constant of the graphite basal plane. Molecules in adjacent rows of a lamella alternate in orientation between the carbon skeletal plane being parallel and perpendicular to the graphite surface. Upon heating, the crystalline monolayers transform to a 'smectic' phase in which the inter-row spacing within a lamella expands by approximately 10% and the molecules are predominantly oriented with the carbon skeletal plane parallel to the graphite surface. In the smectic phase, the MD simulations show evidence of broadening of the lamella boundaries as a result of molecules diffusing parallel to their long axis. At still higher temperatures, they indicate that the introduction of gauche defects into the alkane chains drives a melting transition to a monolayer fluid phase as reported previously.

Taub, H. [University of Missouri, Columbia; Hansen, F.Y. [Technical University of Denmark; Diama, Amand [National University of the Ivory Coast; Matthies, Blake [Goodyear Tire and Rubber Company, The; Criswell, Leah [University of Missouri, Columbia; Mo, Haiding [Advanced Optowave Corporation; Bai, M [University of Missouri, Columbia; Herwig, Kenneth W [ORNL

2009-01-01T23:59:59.000Z

125

An evaluation of the neutron radiography facility at the Nuclear Science Center for dynamic imaging of two-phase hydrogenous fluids  

E-Print Network (OSTI)

Though both film and video radiographic image techniques are available in neutron radiography, radiographic cameras are commonly used to capture the dynamic flow patterns in a rapid sequence of images. These images may be useful to verify two-phase flow models in small diameter flow channels. An initial series of real-time neutron radiography experiments were performed at the Texas A&M University System, Texas Engineering Experiment Station, Nuclear Science Center Reactor (NSCR) to determined the image resolution of two-phase water and air flow regimes through small diameter metal flow channels. After evaluating these initial images, research was conducted to determine cost effective enhancements that would increase the dimensional accuracy and contrast of these flow images. Modifications were completed to the beam collimator and the radiography camera video processing board was realigned to provide a stronger vidio signal with less noise. Several hydrogenous-media reference standards were designed and constructed to evaluate the effectiveness of the modifications. The beamport collimator was redesigned and the radiography calibration methodology was changed. The post-modification images demonstrate that a smaller, more focused neutron beam and a more sensitive video camera provide clearer images with excellent dimensional characteristics. Specific research to quantify both the resolution and sensitivity limits is proposed and a change in dynamic target imaging methodology is proposed.

Carlisle, Bruce Scott

1994-01-01T23:59:59.000Z

126

Locality phase prediction  

Science Conference Proceedings (OSTI)

As computer memory hierarchy becomes adaptive, its performance increasingly depends on forecasting the dynamic program locality. This paper presents a method that predicts the locality phases of a program by a combination of locality profiling and run-time ... Keywords: dynamic optimization, locality analysis and optimization, phase hierarchy, program phase analysis and prediction, reconfigurable architecture

Xipeng Shen; Yutao Zhong; Chen Ding

2004-12-01T23:59:59.000Z

127

Methods for magnetic resonance analysis using magic angle technique  

DOE Patents (OSTI)

Methods of performing a magnetic resonance analysis of a biological object are disclosed that include placing the object in a main magnetic field (that has a static field direction) and in a radio frequency field; rotating the object at a frequency of less than about 100 Hz around an axis positioned at an angle of about 54.degree.44' relative to the main magnetic static field direction; pulsing the radio frequency to provide a sequence that includes a phase-corrected magic angle turning pulse segment; and collecting data generated by the pulsed radio frequency. In particular embodiments the method includes pulsing the radio frequency to provide at least two of a spatially selective read pulse, a spatially selective phase pulse, and a spatially selective storage pulse. Further disclosed methods provide pulse sequences that provide extended imaging capabilities, such as chemical shift imaging or multiple-voxel data acquisition.

Hu, Jian Zhi (Richland, WA); Wind, Robert A. (Kennewick, WA); Minard, Kevin R. (Kennewick, WA); Majors, Paul D. (Kennewick, WA)

2011-11-22T23:59:59.000Z

128

Dynamics of hadron-nucleus interactions  

SciTech Connect

Recent progress in diffraction theory shows that proton-nucleus scattering at nonforward angles is dominated by the interference of waves from two or more bright spots. Analytic formulas based on asymptotic theories of diffraction yield valuable new insights into the scattering and these formulas can be readily extended to illuminate the role of dynamical ingredients, i.e., the nucleon-nucleon amplitudes. The governing parameters of the diffraction and some direct connections between the observed cross sections and the input dynamics are reviewed. New information regarding the nucleon-nucleon parameters based on recent phase shift analyses show some systematic differences from the effective NN amplitudes which produce fits to proton-nucleus diffraction data. Recent progress in understanding the role of ..delta..-isobars in proton-nucleus dynamics is reviewed. 126 references.

Wallace, S.J.

1981-07-01T23:59:59.000Z

129

Phase separation of an asymmetric binary fluid mixture confined in a nanoscopic slit pore: Molecular-dynamics simulations  

E-Print Network (OSTI)

As a generic model system of an asymmetric binary fluid mixture, hexadecane dissolved in carbon dioxide is considered, using a coarse-grained bead-spring model for the short polymer, and a simple spherical particle with Lennard-Jones interactions for the carbon dioxide molecules. In previous work, it has been shown that this model reproduces the real phase diagram reasonable well, and also the initial stages of spinodal decomposition in the bulk following a sudden expansion of the system could be studied. Using the parallelized simulation package ESPResSo on a multiprocessor supercomputer, phase separation of thin fluid films confined between parallel walls that are repulsive for both types of molecules are simulated in a rather large system (1356 x 1356 x 67.8 A^3, corresponding to about 3.2 million atoms). Following the sudden system expansion, a complicated interplay between phase separation in the directions perpendicular and parallel to the walls is found: in the early stages the hexadecane molecules accumulate mostly in the center of the slit pore, but as the coarsening of the structure in the parallel direction proceeds, the inhomogeneity in the perpendicular direction gets much reduced. Studying then the structure factors and correlation functions at fixed distances from the wall, the densities are essentially not conserved at these distances, and hence the behavior differs strongly from spinodal decomposition in the bulk. Some of the characteristic lengths show a nonmonotonic variation with time, and simple coarsening described by power-law growth is only observed if the domain sizes are much larger than the film thickness.

K. Bucior; L. Yelash; K. Binder

2008-04-09T23:59:59.000Z

130

A qualitative perspective on the dynamics of a single-Cooper-pair box with a phase-damped cavity  

E-Print Network (OSTI)

In a recent paper Dajka, et.al., [J. Phys. A \\textbf{40}, F879 (2007)] predicted that some composite systems can be entangled forever even if coupled with a thermal bath. We analyze the transient entanglement of a single-Cooper-pair box biased by a classical voltage and irradiated by a quantized field and find the unusual feature that the phase-damped cavity can lead to a long-lived entanglement. The results show an asymptotic value of the idempotency defect (concurrence) which embodies coherence loss (entanglement survival), independent of the interaction development by dependent critically on environment.

Mahmoud Abdel-Aty

2008-01-18T23:59:59.000Z

131

Estimation of rotor angles of synchronous machines using artificial neural networks and local PMU-based quantities  

Science Conference Proceedings (OSTI)

This paper investigates a possibility for estimating rotor angles in the time frame of transient (angle) stability of electric power systems, for use in real-time. The proposed dynamic state estimation technique is based on the use of voltage and current ... Keywords: Electric power systems, Multilayer perceptrons, Phasor measurement units, Transient stability monitoring and control

Alberto Del Angel; Pierre Geurts; Damien Ernst; Mevludin Glavic; Louis Wehenkel

2007-10-01T23:59:59.000Z

132

Self-adjoint phase operator  

Science Conference Proceedings (OSTI)

and E.V. Damaskinskii ... 1 . Introduction. The problem of quantizing classical action-phase (angle) .... of the ordinary canonical operators Q and P in L2([0, 1])).

133

Materials Small-angle X-ray Scattering (SAXS) | Stanford Synchrotron  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Small-angle X-ray Scattering (SAXS) Materials Small-angle X-ray Scattering (SAXS) Small Angle X-ray Scattering for Materials Science Small-angle X-ray scattering (SAXS) is a well-established characterization method for microstructure investigations in various materials. It probes electron density differences to give information about structural inhomogeneities from the near atomic scale (1 nm) to the micron scale (1 000 nm). The method involves measuring the scattered X-ray intensity as a function of (typically small) scattering angles and is generally performed in transmission. SAXS is used to characterize the size scale of inhomogeneities (e.g. pores, inclusions, second phase regions) in polymer blends, micro-emulsions, geological materials, bones, cements and ceramics. Instrumentation

134

Orientation Angles of a Pulsar's Polarization Vector  

E-Print Network (OSTI)

A statistical model of the polarization of pulsar radio emission is used to derive the general statistics of a polarization vector's orientation angles. The theoretical distributions are compared with orientation angle histograms computed from single-pulse, polarization observations of PSR B2020+28. The favorable agreement between the theoretical and measured distributions lends support to the underlying assumptions of the statistical model, and demonstrates, like recent work on other pulsars, that the handedness of circular polarization is associated with the radiation's orthogonally polarized modes. Comprehensive directional statistics of the vector's orientation angles are also derived, and are shown to follow the Watson bipolar and Fisher distributions in its limiting forms.

Mark M. McKinnon

2006-03-17T23:59:59.000Z

135

A Practical Pyrgeometer Using the Representative Angle  

Science Conference Proceedings (OSTI)

A simple directional pyrgeometer is tested and compared with a conventional standard pyrgeometer. The system presented in this article has a narrow directional response and points to the representative zenith angle of 52.5. Because of its ...

Satoshi Sakai; Aya Ito; Kazuhiro Umetani; Isao Iizawa; Masanori Onishi

2009-03-01T23:59:59.000Z

136

New-generation absolute angle sensors  

Science Conference Proceedings (OSTI)

This paper describes new schemes for absolute angle sensors designed on the modern element base (megapixel CCD- and CMOS-matrices). In these schemes communication between a measured object and a receiving module is organized through an optical channel ...

Yu. A. Grodetskii; Yu. E. Dukarevich; Yu. M. Ivanov

2013-05-01T23:59:59.000Z

137

A Comparative Heat Transfer Examination of Structural Insulated Panels (SIPs) With and Without Phase Change Materials (PCMs) Using a Dynamic Wall Simulator  

E-Print Network (OSTI)

The main focus of this paper was to present data to advance the design of a previously developed thermally-enhanced structural insulated panel (SIP) that had been outfitted with phase change materials (PCMs) (Medina et al., 2008). To advance the development of the previous design, which had only been evaluated under full weather conditions, a set of well-controlled laboratory experiments was carried out. For this, a dynamic wall simulator was built, where a range of important parameters was evaluated. This was done through a comparative heat transfer examination of SIPs, with and without PCMs; where parameters, such as, foam core material of the SIP and material of the PCM holding containers (i.e., encapsulating pipes) were evaluated. Instantaneous heat transfer rates measurements are presented. The two parameters considered (i.e., foam material and pipe material) were found to have first order effects on the performance of PCM-enhanced SIPs. The PCM outfitted SIPs reduced the peak heat fluxes when compared to their own kind, but without PCM. The results indicate that SIPs with molded expanded polystyrene (EPS) cores would benefit more from the PCM enhancement than SIPs with urethane cores. PVC pipes as holding containers for the PCMs did not prove as efficient as metal pipes.

Medina, M.; Zhu, D.

2008-12-01T23:59:59.000Z

138

Surface tension of multi-phase flow with multiple junctions governed by the variational principle  

E-Print Network (OSTI)

We explore a computational model of an incompressible fluid with a multi-phase field in three-dimensional Euclidean space. By investigating an incompressible fluid with a two-phase field geometrically, we reformulate the expression of the surface tension for the two-phase field found by Lafaurie, Nardone, Scardovelli, Zaleski and Zanetti (J. Comp. Phys. \\vol{113} \\yr{1994} \\pages{134-147}) as a variational problem related to an infinite dimensional Lie group, the volume-preserving diffeomorphism. The variational principle to the action integral with the surface energy reproduces their Euler equation of the two-phase field with the surface tension. Since the surface energy of multiple interfaces even with singularities is not difficult to be evaluated in general and the variational formulation works for every action integral, the new formulation enables us to extend their expression to that of a multi-phase ($N$-phase, $N\\ge2$) flow and to obtain a novel Euler equation with the surface tension of the multi-phase field. The obtained Euler equation governs the equation of motion of the multi-phase field with different surface tension coefficients without any difficulties for the singularities at multiple junctions. In other words, we unify the theory of multi-phase fields which express low dimensional interface geometry and the theory of the incompressible fluid dynamics on the infinite dimensional geometry as a variational problem. We apply the equation to the contact angle problems at triple junctions. We computed the fluid dynamics for a two-phase field with a wall numerically and show the numerical computational results that for given surface tension coefficients, the contact angles are generated by the surface tension as results of balances of the kinematic energy and the surface energy.

Shigeki Matsutani; Kota Nakano; Katsuhiko Shinjo

2011-07-13T23:59:59.000Z

139

Non-equilibrium dynamics of a system with Quantum Frustration  

E-Print Network (OSTI)

Using flow equations, equilibrium and non-equilibrium dynamics of a two-level system are investigated, which couples via non-commuting components to two independent oscillator baths. In equilibrium the two-level energy splitting is protected when the TLS is coupled symmetrically to both bath. A critical asymmetry angle separates the localized from the delocalized phase. On the other hand, real-time decoherence of a non-equilibrium initial state is for a generic initial state faster for a coupling to two baths than for a single bath.

Heiner Kohler; Andreas Hackl; Stefan Kehrein

2013-04-06T23:59:59.000Z

140

Electron bunch injection at an angle into a laser wakefield  

E-Print Network (OSTI)

External injection of electron bunches longer than the plasma wavelength in a laser wakefield accelerator can lead to the generation of femtosecond ultrarelativistic bunches with a couple of percent energy spread. Extensive study has been done on external electron bunch (e.g. one generated by a photo-cathode rf linac) injection in a laser wakefield for different configurations. In this paper we investigate a new way of external injection where the electron bunch is injected at a small angle into the wakefield. This way one can avoid the ponderomotive scattering as well as the vacuum-plasma transition region, which tend to destroy the injected bunch. In our simulations, the effect of the laser pulse dynamics is also taken into account. It is shown that injection at an angle can provide compressed and accelerated electron bunches with less than 2% energy spread. Another advantage of this scheme is that it has less stringent requirements in terms of the size of the injected bunch and there is the potential to tr...

Luttikhof, M J H; Van Goor, F A; Boller, K -J

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Building Energy Software Tools Directory: SunAngle Professional Suite  

NLE Websites -- All DOE Office Websites (Extended Search)

SunAngle Professional Suite SunAngle Professional Suite SunAngle Professional logo. More sophisticated, robust, and well-documented version of SunAngle for people interested in better understanding the calculation methodology or developing their own solar angle calculation tools. The Professional Suite includes well-documented HTML/JavaScript and Microsoft Excel versions of SunAngle, plus a detailed technical manual explaining how to perform all of the underlying calculations. Screen Shots Keywords sun angle, solar calculator Validation/Testing Outputs of the SunAngle Professional Suite were compared to published standard sources of solar angle data; this is documented in the SunAngle Technical Manual. Expertise Required Knowledge of HTML, JavaScript, and/or Microsoft Excel, if the user wishes

142

PRINCIPLE OF GLOBAL DECOUPLING WITH COUPLING ANGLE MODULATION.  

Science Conference Proceedings (OSTI)

The global betatron decoupling on the ramp is an important issue for the operation of the Relativistic Heavy Ion Collider (RHIC). A new scheme, coupling angle modulation, was found. By modulating two orthogonal skew quadrupole families, an extra rotating coupling is introduced into the coupled machine. The skew quadrupole modulation frequency is about 0.2Hz for the RHIC ramp, and 0.5Hz at injection and store. The eigentune changes are tracked with a high resolution phase lock loop (PLL) tune measurement system. The global coupling correction strengths are determined by the modulation skew quadrupole strengths at the minimum eigentune split multiplied by a factor k. k is determined by the uncoupled eigentune split and the maximum and the minimum tune split during the skew quadrupole modulation. This decoupling scheme is fast and robust. It had been verified at the RHIC and has been applied for the RHIC global decoupling on the ramp. In this article, the principle of the coupling angle modulation is presented in detail. Simulation results are also shown.

LUO, Y.; PILAT, F.; PEGGS, S.; TRBOJEVIC, D.; ROSER, T.

2005-05-16T23:59:59.000Z

143

Solar concentrator with restricted exit angles  

DOE Patents (OSTI)

A device is provided for the collection and concentration of radiant energy and includes at least one reflective side wall. The wall directs incident radiant energy to the exit aperture thereof or onto the surface of energy absorber positioned at the exit aperture so that the angle of incidence of radiant energy at the exit aperture or on the surface of the energy absorber is restricted to desired values.

Rabl, Arnulf (Downers Grove, IL); Winston, Roland (Chicago, IL)

1978-12-19T23:59:59.000Z

144

Small Angle X-Ray Scattering Detector  

DOE Patents (OSTI)

A detector for time-resolved small-angle x-ray scattering includes a nearly constant diameter, evacuated linear tube having an end plate detector with a first fluorescent screen and concentric rings of first fiber optic bundles for low angle scattering detection and an annular detector having a second fluorescent screen and second fiber optic bundles concentrically disposed about the tube for higher angle scattering detection. With the scattering source, i.e., the specimen under investigation, located outside of the evacuated tube on the tube's longitudinal axis, scattered x-rays are detected by the fiber optic bundles, to each of which is coupled a respective photodetector, to provide a measurement resolution, i.e., dq/q, where q is the momentum transferred from an incident x-ray to an x-ray scattering specimen, of 2% over two (2) orders of magnitude in reciprocal space, i.e., qmax/qmin approx=lO0.

Hessler, Jan P.

2004-06-15T23:59:59.000Z

145

IR OPTICS MEASUREMENT WITH LINEAR COUPLING'S ACTION-ANGLE PARAMETERIZATION.  

Science Conference Proceedings (OSTI)

A parameterization of linear coupling in action-angle coordinates is convenient for analytical calculations and interpretation of turn-by-turn (TBT) beam position monitor (BPM) data. We demonstrate how to use this parameterization to extract the twiss and coupling parameters in interaction regions (IRs), using BPMs on each side of the long IR drift region. The example of TBT BPM analysis was acquired at the Relativistic Heavy Ion Collider (RHIC), using an AC dipole to excite a single eigenmode. Besides the full treatment, a fast estimate of beta*, the beta function at the interaction point (IP), is provided, along with the phase advance between these BPMs. We also calculate and measure the waist of the beta function and the local optics.

LUO, Y.; BAI, M.; PILAT, R.; SATOGATA, T.; TRBOJEVIC, D.

2005-05-16T23:59:59.000Z

146

LHC luminosity upgrade with large Piwinski angle scheme: a recent look  

Science Conference Proceedings (OSTI)

Luminosity upgrade at the LHC collider using longitudinally flat bunches in combination with the large crossing angle (large Piwinski angle scheme) is being studied with renewed interest in recent years. By design, the total beam-beam tune shift at the LHC is less than 0.015 for two interaction points together. But the 2010-11 3.5 TeV collider operation and dedicated studies indicated that the beam-beam tune shift is >0.015 per interaction point. In view of this development we have revisited the requirements for the Large Piwinski Angle scheme at the LHC. In this paper we present a new set of parameters and luminosity calculations for the desired upgrade by investigating: (1) current performance of the LHC injectors, (2) e-cloud issues on nearly flat bunches and (3) realistic beam particle distributions from longitudinal beam dynamics simulations. We also make some remarks on the needed upgrades on the LHC injector accelerators.

Bhat, C.M.; /Fermilab; Zimmermann, f.; /CERN

2011-09-01T23:59:59.000Z

147

Regge calculus from a new angle  

E-Print Network (OSTI)

In Regge calculus space time is usually approximated by a triangulation with flat simplices. We present a formulation using simplices with constant sectional curvature adjusted to the presence of a cosmological constant. As we will show such a formulation allows to replace the length variables by 3d or 4d dihedral angles as basic variables. Moreover we will introduce a first order formulation, which in contrast to using flat simplices, does not require any constraints. These considerations could be useful for the construction of quantum gravity models with a cosmological constant.

Benjamin Bahr; Bianca Dittrich

2009-07-24T23:59:59.000Z

148

Anomalous and resonance small angle scattering  

SciTech Connect

Significant changes in the small angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous dispersion terms for the scattering factor (x-rays) or scattering length (neutrons). The physics inherent in these anomalous dispersion terms is first discussed before considering how they enter the relevant scattering theory. Two major areas of anomalous scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with x-rays. However, it is pointed out that the formalism is the same or the analogue experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small-angle neutron scatterings are discussed. 8 figs.

Epperson, J.E.; Thiyagarajan, P.

1987-11-01T23:59:59.000Z

149

Anomalous and resonance small angle scattering: Revision  

SciTech Connect

Significant changes in the small angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous dispersion terms for the scattering factor (x-rays) or scattering length (neutrons). The physics inherent in these anomalous dispersion terms is first discussed before considering how they enter the relevant scattering theory. Two major areas of anomalous scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with x-rays. However, it is pointed out that the formalism is the same for the analogue experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small angle neutron scatterings are discussed. 54 refs., 8 figs., 1 tab.

Epperson, J.E.; Thiyagarajan, P.

1987-11-01T23:59:59.000Z

150

The electric dipole moment of the nucleon from simulations at imaginary vacuum angle theta  

E-Print Network (OSTI)

We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N_f=2 flavors of dynamical quarks at imaginary vacuum angle theta. The calculation proceeds via the CP odd form factor F_3. A novel feature of our calculation is that we use partially twisted boundary conditions to extract F_3 at zero momentum transfer. As a byproduct, we test the QCD vacuum at nonvanishing theta.

R. Horsley; T. Izubuchi; Y. Nakamura; D. Pleiter; P. E. L. Rakow; G. Schierholz; J. Zanotti

2008-08-10T23:59:59.000Z

151

PARMTEQ (Phase And Radial Motion in Transverse Electric Quadrupole linacs): A beam dynamics code for the RFQ (radio-frequency quadrupole)  

SciTech Connect

The PARMTEQ code is used for generating the complete cell design of a radio-frequency quadrupole linear accelerator and for multiparticle simulation of the beam dynamics. We present a review of the code, with an emphasis on the physics used to describe the particle motion and the cell generation. 9 refs., 1 fig.

Crandall, K.R.; Wangler, T.P.

1987-01-01T23:59:59.000Z

152

Alternative IR geometries for TESLA with a small crossing angle  

E-Print Network (OSTI)

The formulation of hybrid crossing angle schemes has been a recent development of the TESLA collision geometry debate. Here we report on two such schemes, characterised by either a small vertical or horizontal beam crossing angle.

R. Appleby; D. Angal-Kalinin; P. Bambade; B. Mouton; O. Napoly; J. Payet; the TESLA Collaboration

2004-12-09T23:59:59.000Z

153

Phase behavior, structure, and properties of model block polymers. Final report, 15 April 1990-14 October 1993  

Science Conference Proceedings (OSTI)

This project brought together three distinct experimental methods in an integrated investigation of the phase behavior, structure and properties of block copolymers in the vicinity of the order-disorder transition. Anionic polymerization of polydiene diblock copolymers followed by catalytic hydrogenation was used to produce three classes of model saturated hydrocarbon materials. Dynamic mechanical spectroscopy and large amplitude dynamic shearing were employed to probe and manipulate, respectively, the melt state microstructure. Small angle neutron scattering (SANS) experiments provided detailed information regarding the structure of the materials. A significant achievement during this work was the development of a dynamic shearing device that could be operated in situ with a SANS instrument. Together with the spectrum of materials produced, this combined scattering-rheology technique has led to a qualitative improvement in the understanding of block copolymer phase behavior, and uncovered a rich polymorphism that is accompanied by dramatic variations in physical properties. Two new parameters have been shown to play a crucial role in determining block copolymer phase behavior. The degree of polymerization, controls the extent of composition fluctuations which strongly affects the types of phases encountered near the order-disorder transition. Conformational asymmetry, which is controlled by the block volume and radius of gyration, leads to different phases on either side of the phase diagram. These effects have not been accounted for theoretically.

Bates, F.S.

1993-10-14T23:59:59.000Z

154

Medium energy pitch angle distribution during substorm injected electron clouds  

E-Print Network (OSTI)

Medium energy pitch angle distribution during substorm injected electron clouds A. A° snes,1 J, N. ?stgaard, and M. Thomsen (2005), Medium energy pitch angle distribution during substorm injected to obtain pitch angle resolved electron distribution data for measurements at energies 10 eV to 47 keV. [3

Bergen, Universitetet i

155

Large-angle Parabolic Equation Methods James T. Kirby*  

E-Print Network (OSTI)

CHAPTER 32 Large-angle Parabolic Equation Methods James T. Kirby* Large-angle parabolic equation of the parabolic equation method (PEM) to any relevant wave propagation problem implies that a principal is to examine two methods of extending the basic parabolic equation method to include large-angle effects

Kirby, James T.

156

FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION  

E-Print Network (OSTI)

FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION GEORGIOS AKRIVIS Abstract. We consider a model initial and boundary value problem for the wide-angle `parabolic' equation Lur = icu, the wide-angle `parabolic'equation of underwater acoustics. Given R > 0, µ 0, > 0, , and q real

Akrivis, Georgios

157

SIMULATING THE EFFECTS OF INITIAL PITCH-ANGLE DISTRIBUTIONS ON SOLAR FLARES  

SciTech Connect

In this work, we model both the thermal and non-thermal components of solar flares. The model we use, HYLOOP, combines a hydrodynamic equation solver with a non-thermal particle tracking code to simulate the thermal and non-thermal dynamics and emission of solar flares. In order to test the effects of pitch-angle distribution on flare dynamics and emission, a series of flares is simulated with non-thermal electron beams injected at the loop apex. The pitch-angle distribution of each beam is described by a single parameter and allowed to vary from flare to flare. We use the results of these simulations to generate synthetic hard and soft X-ray emissions (HXR and SXR). The light curves of the flares in Hinode's X-ray Telescope passbands show a distinct signal that is highly dependent on pitch-angle distribution. The simulated HXR emission in the 3-6 keV bandpass shows the formation and evolution of emission sources that correspond well to the observations of pre-impulsive flares. This ability to test theoretical models of thermal and non-thermal flare dynamics directly with observations allows for the investigation of a wide range of physical processes governing the evolution of solar flares. We find that the initial pitch-angle distribution of non-thermal particle populations has a profound effect on loop top HXR and SXR emission and that apparent motion of HXR is a natural consequence of non-thermal particle evolution in a magnetic trap.

Winter, Henry D.; Reeves, Katharine K. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 58, Cambridge, MA 02138 (United States); Martens, Petrus, E-mail: hwinter@cfa.harvard.edu [Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717 (United States)

2011-07-10T23:59:59.000Z

158

Imaging Narrow Angle The Voyager Spacecraft  

E-Print Network (OSTI)

of the mission has allowed us to explore the most distant reaches of our heliosphere and allowed us to take to characterize the far outer heliosphere, the distant solar wind, and the interaction between the two. This phase spacecraft are exploring regions of space never before encountered, building on the legacy of one of NASA

159

Phase Stability, Phase Transformations, and Reactive Phase ...  

Science Conference Proceedings (OSTI)

Jul 31, 2012 ... New Phase in Stoichiometric Cu6Sn5 and Effect of Ni Addition on Phase Stabilization in Wide Temperature Range Optical Properties of...

160

Phase Diagrams  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Computational Thermodynamics and Kinetics: Phase Diagrams ... TMS: Alloy Phases Committee, TMS: Chemistry and Physics of Materials...

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Partial Dynamical Symmetry and Mixed Dynamics  

E-Print Network (OSTI)

Partial dynamical symmetry describes a situation in which some eigenstates have a symmetry which the quantum Hamiltonian does not share. This property is shown to have a classical analogue in which some tori in phase space are associated with a symmetry which the classical Hamiltonian does not share. A local analysis in the vicinity of these special tori reveals a neighbourhood of phase space foliated by tori. This clarifies the suppression of classical chaos associated with partial dynamical symmetry. The results are used to divide the states of a mixed system into ``chaotic'' and ``regular'' classes.

A. Leviatan; N. D. Whelan

1996-08-24T23:59:59.000Z

162

Definition: Transmission Angle and Frequency Monitoring | Open Energy  

Open Energy Info (EERE)

Transmission Angle and Frequency Monitoring Transmission Angle and Frequency Monitoring Jump to: navigation, search Dictionary.png Transmission Angle and Frequency Monitoring An advanced transmission application that uses angle and frequency measurements from PMUs to indicate loss of generation or other disturbances causing a change in the supply/demand balance.[1] Related Terms transmission lines, advanced transmission applications, transmission line References ↑ https://www.smartgrid.gov/category/technology/transmission_angle_and_frequency_monitoring [[Cat LikeLike UnlikeLike You like this.Sign Up to see what your friends like. egory: Smart Grid Definitionssmart grid,smart grid, |Template:BASEPAGENAME]]smart grid,smart grid, Retrieved from "http://en.openei.org/w/index.php?title=Definition:Transmission_Angle_and_Frequency_Monitoring&oldid=502506

163

Ponderomotive phase plate for transmission electron microscopes  

Science Conference Proceedings (OSTI)

A ponderomotive phase plate system and method for controllably producing highly tunable phase contrast transfer functions in a transmission electron microscope (TEM) for high resolution and biological phase contrast imaging. The system and method includes a laser source and a beam transport system to produce a focused laser crossover as a phase plate, so that a ponderomotive potential of the focused laser crossover produces a scattering-angle-dependent phase shift in the electrons of the post-sample electron beam corresponding to a desired phase contrast transfer function.

Reed, Bryan W. (Livermore, CA)

2012-07-10T23:59:59.000Z

164

Small-angle Synchrotron Diffraction Study of Partially Gasified Coal ...  

Science Conference Proceedings (OSTI)

Presentation Title, Small-angle Synchrotron Diffraction Study of Partially Gasified Coal Chars. Author(s), Keith Gordon McLennan, Daniel Roberts, Richard...

165

The Extended Q-Range Small Angle Neutron Scattering ...  

Science Conference Proceedings (OSTI)

Abstract Scope, The Extended Q-Range Small Angle Neutron Scattering Diffractometer (EQ-SANS) at the Spallation Neutron Source (SNS) is a high intensity...

166

Industrial Applications at Small Angle Neutron Scattering and ...  

Science Conference Proceedings (OSTI)

... at Small Angle Neutron Scattering and Neutron Diffraction of HANARO Reactor .... Structure/Microstructure Analysis of Faulted and Modular Materials from...

167

Laser warning receiver to identify the wavelength and angle of ...  

A laser warning receiver is disclosed which has up to hundreds of individual optical channels each optically oriented to receive laser light from a different angle of ...

168

Building Energy Software Tools Directory: SunAngle  

NLE Websites -- All DOE Office Websites (Extended Search)

Calculates solar angles based on location, date, and time. It's useful in passive solar building design, PV and solar thermal system design and analysis, and other...

169

USANS: the Ultra-Small-Angle Neutron Scattering Instrument at...  

NLE Websites -- All DOE Office Websites (Extended Search)

USANS-Ultra-Small-Angle Neutron Scattering Instrument USANS is designed for the study of hierarchical structures in natural and artificial materials. It can be considered an...

170

High Temperature, Large Sample Volume, Constant Flow Magic Angle Spinning NMR Probe for a 11  

NLE Websites -- All DOE Office Websites (Extended Search)

High Temperature, Large Sample Volume, Constant Flow Magic Angle Spinning NMR Probe for a High Temperature, Large Sample Volume, Constant Flow Magic Angle Spinning NMR Probe for a 11.7 T Magnetic Field for In Situ Catalytic Reaction Characterization Project start date: April 1, 2007 EMSL Lead Investigator: Joseph Ford, EMSL High Field Magnetic Resonance Facility Co-investigators: Jian Zhi Hu, Macromolecular Structure and Dynamics, Biological Science Division, FCSD Jesse Sears and David W. Hoyt, EMSL High Field Magnetic Resonance Facility Detailed understanding of the mechanisms involved in a catalytic reaction requires identification of the nature of the active sites and the temporal evolution of reaction intermediates. Although optical methods such as UV-visible and infrared (IR) spectroscopies can be used for some types of reactions, these do not

171

Phase Field Simulations  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... The anisotropic solid-vapor surface energy for a 2D PFC hexagonal crystal is ... Finally, we examine the dynamic case of step-flow growth of a crystal into ... Thermal and Dispersed-Phase Analysis of Nano Fluid Using CFD-A Hybrid ... gas turbine power generation systems because of its high melting point,...

172

Phase five  

NLE Websites -- All DOE Office Websites (Extended Search)

Phase five Phase five 1663 Los Alamos science and technology magazine Latest Issue:November 2013 All Issues » submit Phase five Los Alamos physicists have conclusively demonstrated the existence of a new phase of matter. November 25, 2013 Phase five Scientists still have more to learn about the exotic physics of specialty materials. What makes the cuprates special? How about a new phase of matter. Ceramic metals known as cuprates have mystified physicists for decades. They exhibit a variety of distinct phases of matter, each with its own specific properties, including a phase bearing an exotic type of magnetism, a high-temperature superconducting phase, an ordinary metal phase, a poorly understood and weird metallic phase simply called a strange metal, and an equally poorly understood metallic phase known as the pseudogap. The

173

POLY-FREE CONSTRUCTIONS FOR RIGHT-ANGLED ARTIN GROUPS  

E-Print Network (OSTI)

POLY-FREE CONSTRUCTIONS FOR RIGHT-ANGLED ARTIN GROUPS SUSAN HERMILLER1 AND ZORAN SUNI´C Abstract. We show that every right-angled Artin group A defined by a graph of finite chromatic number is poly-free with poly-free length bounded between the clique number and the chromatic number of . Further

Hermiller, Susan

174

Dynamics of quantum spin liquid and spin solid phases in IPA-CuCl3 under an applied magnetic field studied with neutron scattering  

SciTech Connect

Inelastic and elastic neutron scattering is used to study spin correlations in the quasi-one-dimensional quantum antiferromagnet IPA-CuCl3 in strong applied magnetic fields. A condensation of magnons and commensurate transverse long-range ordering is observe at a critical field Hc=9.5 T. The field dependencies of the energies and polarizations of all magnon branches are investigated both below and above the transition point. Their dispersion is measured across the entire one-dimensional Brillouin zone in magnetic fields up to 14 T. The critical wave vector of magnon spectrum truncation Masuda et al., Phys. Rev. Lett. 96, 047210 2006 is found to shift from hc0,35 at HHC to hc=0.25 for HHC. A drastic reduction of magnon bandwidths in the ordered phase Garlea et al., Phys. Rev. Lett. 98, 167202 2007 is observed and studied in detail. New features of the spectrum, presumably related to this bandwidth collapse, are observed just above the transition field.

Zheludev, Andrey I [ORNL; Garlea, Vasile O [ORNL; Masuda, T. [Yokohama City University, Japan; Manaka, H. [Kagoshima University, Kagoshima JAPAN; Regnault, L.-P. [CEA, Grenoble, France; Ressouche, E. [CEA, Grenoble, France; Grenier, B. [CEA, Grenoble, France; Chung, J.-H. [National Institute of Standards and Technology (NIST); Qiu, Y. [National Institute of Standards and Technology (NIST); Habicht, Klaus [Hahn-Meitner Institut, Berlin, Germany; Kiefer, K. [Hahn-Meitner Institut, Berlin, Germany; Boehm, Martin [Institut Laue-Langevin (ILL)

2007-01-01T23:59:59.000Z

175

Complete breakdown of the Debye model of rotational relaxation near the isotropic-nematic phase boundary: Effects of intermolecular correlations in orientational dynamics  

E-Print Network (OSTI)

The Debye-Stokes-Einstein (DSE) model of rotational diffusion predicts that the rotational correlation times $\\tau_{l}$ vary as $[l(l+1)]^{-1}$, where $l$ is the rank of the orientational correlation function (given in terms of the Legendre polynomial of rank $l$). One often finds significant deviation from this prediction, in either direction. In supercooled molecular liquids where the ratio $\\tau_{1}/\\tau_{2}$ falls considerably below three (the Debye limit), one usually invokes a jump diffusion model to explain the approach of the ratio $\\tau_{1}/\\tau_{2}$ to unity. Here we show in a computer simulation study of a standard model system for thermotropic liquid crystals that this ratio becomes much less than unity as the isotropic-nematic phase boundary is approached from the isotropic side. Simultaneously, the ratio $\\tau_2/\\eta$ (where $\\eta$ is the shear viscosity of the liquid) becomes {\\it much larger} than hydrodynamic value near the I-N transition. We have also analyzed the break down of the Debye model of rotational diffusion in ratios of higher order rotational correlation times. We show that the break down of the DSE model is due to the growth of orientational pair correlation and provide a mode coupling theory analysis to explain the results.

Prasanth P. Jose; Dwaipayan Chakrabarti; Biman Bagchi

2005-12-16T23:59:59.000Z

176

Dynamical Self-Assembly of Nanocrystal Superlattices during Colloidal...  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynamical Self-Assembly of Nanocrystal Superlattices during Colloidal Droplet Evaporation by in situ Small Angle X-Ray Scattering S. Narayanan, J. Wang, X.-M. Lin (Argonne National...

177

Enhancing Condensers for Geothermal Systems: the Effect of High Contact Angles on Dropwise Condensation Heat Transfer  

DOE Green Energy (OSTI)

Phase change heat transfer is notorious for increasing the irreversibility of, and therefore decreasing the efficiency of, geothermal power plants. Its significant contribution to the overall irreversibility of the plant makes it the most important source of inefficiency in the process. Recent studies here have shown the promotion of drop wise condensation in the lab by means of increasing the surface energy density of a tube with nanotechnology. The use of nanotechnology has allowed the creation of surface treatments which discourage water from wetting a tube surface during a static test. These surface treatments are unique in that they create high- contact angles on the condensing tube surfaces to promote drop wise condensation.

Kennedy, John M.; Kim, Sunwoo; Kim, Kwang J.

2009-10-06T23:59:59.000Z

178

Angle of crack propagation for a vertical hydraulic fracture  

DOE Green Energy (OSTI)

Using the strain-energy-density-factor (S) theory, the positive fracture angle +theta/sub o/ (the initial fracture angle of crack propagation) of a near-vertical crack is predicted by using the opening- and sliding-mode stress-intensity factors in the presence of the overburden pressure, the least in situ horizontal principal stress, and the borehole fluid pressure. The crack spreads in the positive theta/sub o/ direction (counter-clockwise) in the plane for which S is a minimum, S/sub min/. It was verified that S/sub min/ is greater than or equal to S/sub c/. The quantity S/sub c/ is defined as the critical value of S, and remains essentially constant. Of interest is the numerical example for calculating fracture angle and the critical uniform borehole fluid pressure required to initiate fracture at such an angle for the present LASL Dry Hot Rock Geothermal Energy Program. (auth)

Sarda, J.P.; Hsu, Y.C.

1975-12-01T23:59:59.000Z

179

A multiresolution spectral angle-based hyperspectral classification method  

Science Conference Proceedings (OSTI)

Due to the lack of training samples, hyperspectral classification often adopts the minimum distance classification method based on spectral metrics. This paper proposes a novel multiresolution spectral-angle-based hyperspectral classification method, ...

Jin Chen; Runsheng Wang; Cheng Wang

2008-06-01T23:59:59.000Z

180

Modtran radiance modeling of multi-angle worldview-2 imagery .  

E-Print Network (OSTI)

??The WorldView-2 satellite, launched in 2010 by DigitalGlobe, provides researchers with the ability to collect high resolution, multi-angle, 8-band multispectral imagery. This offers a unique (more)

Marshall, Samuel I.

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Multi-angle technique for measurement of ground source emission  

SciTech Connect

TAISIR, the Temperature and Imaging System Infrared, is a nominally satellite based platform for remote sensing of the earth. One of its design features is to acquire atmospheric data simultaneous with ground data, resulting in minimal dependence on external atmospheric models for data correction. One technique we employ to acquire atmospheric data is a true multi-angle data acquisition technique. Previous techniques have used only two angles. Here we demonstrate the advantage of using a large number of viewing angles to overconstrain the inversion problem for critical atmospheric and source parameters. For reasonable data acquisition scenarios, simulations show source temperature errors of less than 1K should be possible. Tradeoffs between flight geometry, number of look angles,, and system signal-to-noise are given for typical parameter ranges.

Henderson, J.R.

1995-04-01T23:59:59.000Z

182

Angle Instability Detection in Power Systems with High Wind Penetration  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Angle Instability Detection in Power Angle Instability Detection in Power Systems with High Wind Penetration Using PMUs YC Zhang National Renewable Energy Laboratory Yingchen.zhang@nrel.gov 27/28 June 2013 Washington, DC DOE/OE Transmission Reliability Program Angle Instability Detection in Power Systems with High Wind Penetration Using Synchrophasor Measurements  Project Objective * Utilize synchrophasor measurements to estimate the equivalent inertia of a power source such as synchronous generators or wind turbine generators * Develop angle instability detection method for a system with high wind penetration using the synchrophasor measurements 2 3 Background Submitted to IEEE Journal of Emerging and Selected Topics in Power Electronics * In case of angular instability, some machines will have

183

Limbus Impact on Off-angle Iris Degradation  

SciTech Connect

The accuracy of iris recognition depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. Off-angle iris recognition is a new research focus in biometrics that tries to address several issues including corneal refraction, complex 3D iris texture, and blur. In this paper, we present an additional significant challenge that degrades the performance of the off-angle iris recognition systems, called the limbus effect . The limbus is the region at the border of the cornea where the cornea joins the sclera. The limbus is a semitransparent tissue that occludes a side portion of the iris plane. The amount of occluded iris texture on the side nearest the camera increases as the image acquisition angle increases. Without considering the role of the limbus effect, it is difficult to design an accurate off-angle iris recognition system. To the best of our knowledge, this is the first work that investigates the limbus effect in detail from a biometrics perspective. Based on results from real images and simulated experiments with real iris texture, the limbus effect increases the hamming distance score between frontal and off-angle iris images ranging from 0.05 to 0.2 depending upon the limbus height.

Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

2013-01-01T23:59:59.000Z

184

Phase Field, Phase Field Crystal, Diffusive Molecular Dynamics  

Science Conference Proceedings (OSTI)

Mar 7, 2013... growth of quantum dots on thin membranes and the creation of superstructures (stripes, honeycomb and triangular) in ultrathin films of Cu on...

185

Localized in Vivo Isotropic-Anisotropic Correlation 1H NMR Spectroscopy Using Ultraslow Magic Angle Spinning  

Science Conference Proceedings (OSTI)

Previous work has shown that it is possible to separate the susceptibility broadening in the 1H NMR metabolite spectrum obtained in a live mouse from the isotropic information, thus significantly increasing the spectral resolution. This was achieved using ultra-slow magic angle spinning of the animal combined with a modified phase-corrected magic angle turning (PHORMAT) pulse sequence. However, PHORMAT cannot be used for spatially selective spectroscopy. In this article a modified sequence called LOCMAT (localized magic angle turning) is introduced that makes this possible. Proton LOCMAT spectra are shown for the liver and heart of a live mouse, while spinning the animal at a speed of 4 Hz in a 2 Tesla field. It was found that even in this relatively low field LOCMAT provided isotropic line widths that are a factor 4-10 times smaller than the ones obtained in a stationary animal, and that the susceptibility broadening of the heart metabolites shows unusual features not observed for a dead animal. Finally, the limitations of LOCMAT and possible ways to improve the technique are discussed. It is concluded that in vivo LOCMAT can significantly enhance the utility of NMR spectroscopy for biomedical research.

Wind, Robert A.; Hu, Jian Zhi; Majors, Paul D.

2006-01-01T23:59:59.000Z

186

Entanglement dynamics during decoherence  

Science Conference Proceedings (OSTI)

The evolution of the entanglement between oscillators that interact with the same environment displays highly non-trivial behavior in the long time regime. When the oscillators only interact through the environment, three dynamical phases were identified ... Keywords: 03.65.Yz, 03.67.Bg, 03.67.Mn, 05.40.Jc, Decoherence, Entanglement, Quantum Brownian Motion

Juan Pablo Paz; Augusto J. Roncaglia

2009-12-01T23:59:59.000Z

187

Unwinding relaxation dynamics of polymers  

E-Print Network (OSTI)

The relaxation dynamics of a polymer wound around a fixed obstacle constitutes a fundamental instance of polymer with twist and torque and it is of relevance also for DNA denaturation dynamics. We investigate it by simulations and Langevin equation analysis. The latter predicts a relaxation time scaling as a power of the polymer length times a logarithmic correction related to the equilibrium fluctuations of the winding angle. The numerical data support this result and show that at short times the winding angle decreases as a power-law. This is also in agreement with the Langevin equation provided a winding-dependent friction is used, suggesting that such reduced description of the system captures the basic features of the problem.

Jean-Charles Walter; Marco Baiesi; Gerard Barkema; Enrico Carlon

2013-01-13T23:59:59.000Z

188

A two-phase method for selecting IMRT treatment beam angles ...  

E-Print Network (OSTI)

Sep 8, 2011 ... Penalty coefficient for hot spots on OAR ?n ...... ation therapy of non-small-cell lung cancers, International Journal of. Radiation Oncology...

189

Exploring Competing Orders in the High-Tc Cuprate Phase Diagram Using Angle Resolved Photoemission Spectroscopy  

E-Print Network (OSTI)

the competing order. Does this order fundamentally compete,see in Section 4.3, this order does not appear to correspondunit cells on the order 10? A, ARPES does not have good bulk

Garcia, Daniel Robert

2010-01-01T23:59:59.000Z

190

The effect of electron beam pitch angle and density gradient on solar type III radio bursts  

SciTech Connect

1.5D particle-in-cell simulations of a hot, low density electron beam injected into magnetized, maxwellian plasma were used to further explore the alternative non-gyrotropic beam driven electromagnetic (EM) emission mechanism, first studied in Tsiklauri, Phys. Plasmas 18, 052903 (2011). Variation of beam injection angle and background density gradient showed that the emission process is caused by the perpendicular component of the beam injection current, whereas the parallel component only produces Langmuir waves, which play no role in the generation of EM waves in our mechanism. Particular emphasis was put on the case, where the beam is injected perpendicularly to the background magnetic field, as this turned off any electrostatic wave generation along the field and left a purely electromagnetic signal in the perpendicular components. The simulations establish the following key findings: (i) Initially, waves at a few {omega}{sub ce}/{gamma} are excited, mode converted and emitted at Almost-Equal-To {omega}{sub pe} (ii) The emission intensity along the beam axis is proportional to the respective component of the kinetic energy of the beam; (iii) The frequency of the escaping EM emission is independent of the injection angle; (iv) A stronger background density gradient causes earlier emission; (v) The beam electron distribution function in phase space shows harmonic oscillation in the perpendicular components at the relativistic gyrofrequency; (vi) The requirement for cyclotron maser emission, ({partial_derivative}f/{partial_derivative}v{sub Up-Tack })>0, is fulfilled; (vii) The degree of linear polarization of the emission is strongly dependent on the beam injection angle; (viii) The generated electromagnetic emission is left-hand elliptically polarized as the pitch angle tends to 90 Degree-Sign ; and (ix) The generated electromagnetic energy is of the order of 0.1% of the initial beam kinetic energy.

Pechhacker, R.; Tsiklauri, D. [School of Physics and Astronomy, Queen Mary University of London, E1 4NS (United Kingdom)

2012-11-15T23:59:59.000Z

191

Equilibrium gas-liquid-solid contact angle from density-functional theory  

E-Print Network (OSTI)

We investigate the equilibrium of a fluid in contact with a solid boundary through a density-functional theory. Depending on the conditions, the fluid can be in one phase, gas or liquid, or two phases, while the wall induces an external field acting on the fluid particles. We first examine the case of a liquid film in contact with the wall. We construct bifurcation diagrams for the film thickness as a function of the chemical potential. At a specific value of the chemical potential, two equally stable films, a thin one and a thick one, can coexist. As saturation is approached, the thickness of the thick film tends to infinity. This allows the construction of a liquid-gas interface that forms a well defined contact angle with the wall.

Pereira, Antonio

2010-01-01T23:59:59.000Z

192

Phase-field Simulations/Molecular Dynamics  

Science Conference Proceedings (OSTI)

The sharp interface model was used to determine the SLI free energy and its anisotropy by fitting to the MD data. Finally, the MD simulation of the B2 growth...

193

NCNR Scaling of Membrane Phase Dynamics  

Science Conference Proceedings (OSTI)

... Authors. L. Porcar Oak Ridge National Laboratory Oak Ridge, TN 37831-6393 Present address: University of Maryland College Park, MD 20742. ...

194

Contact Angle of the Colloidal Liquid-Gas Interface and a Hard Wall  

E-Print Network (OSTI)

We consider the Asakura-Oosawa-Vrij model of hard sphere colloids and ideal polymer coils in contact with a planar hard wall at (colloidal) liquid-gas coexistence. Using extensive numerical density functional calculations, the liquid-gas, wall-liquid and wall-gas interfacial free energies are calculated. The results are inserted into Young's equation to obtain the contact angle between the liquid-gas interface and the wall. As a function of polymer fugacity this angle exhibits discontinuities of slope (``kinks'') upon crossing first-order surface phase transitions located on the gas branch of the bulk binodal. Each kink corresponds to a transition from n-1 to $n$ colloid layers adsorbed at the wall, referred to as the n'th layering transition. The corresponding adsorption spinodal points from n-1 to n layers upon reducing the polymer fugacity along the bulk binodal were found in a previous study (J. M. Brader et al. J. Phys.: Cond. Matt., 14: L1, 2002; Mol. Phys., 101: 3349, 2003). Remarkably, we find desorption spinodal points from n to n-1 layers to be absent upon increasing polymer fugacity at bulk coexistence, and many branches (containing up to 7 colloid layers) remain metastable. Results for the first layering binodal and both spinodal branches off-bulk coexistence hint at a topology of the surface phase diagram consistent with these findings. Both the order of the transition to complete wetting and whether it is preceded by a finite or an infinite number of layering transitions remain open questions. We compare the locations of the first layering binodal line and of the second layering binodal point at bulk coexistence with recent computer simulation results by Dijkstra and van Roij (Phys. Rev. Lett., 89: 208303, 2002) and discuss our results for the contact angle in the light of recent experiments.

Paul P. F. Wessels; Matthias Schmidt; Hartmut Lowen

2004-05-07T23:59:59.000Z

195

From a Single-Band Metal to a High-Temperature Superconductor via Two Thermal Phase Transitions  

SciTech Connect

The nature of the pseudogap phase of cuprate high-temperature superconductors is one of the most important unsolved problems in condensed matter physics. We studied the commencement of the pseudogap state at temperature T* using three different techniques (angle-resolved photoemission spectroscopy, polar Kerr effect, and time-resolved reflectivity) on the same optimally-doped Bi2201 crystals. We observe the coincident onset at T* of a particle-hole asymmetric antinodal gap, a non-zero Kerr rotation, and a change in the relaxational dynamics, consistent with a phase transition. Upon further cooling, spectroscopic signatures of superconductivity begin to grow close to the superconducting transition temperature (T{sub c}), entangled in an energy-momentum dependent fashion with the pre-existing pseudogap features.

He, R.-H.; Hashimoto, M.; Karapetyan, H.; Koralek, J.D.; Hinton, J.P.; Testaud, J.P.; Nathan, V.; Yoshida, Y.; Yao, H.; Tanaka, K.; Meevasana, W.; Moore, R.G.; Lu, D.H.; Mo, S.-K.; Ishikado, M.; Eisaki, H.; Hussain, Z.; Devereaux, T.P.; Kivelson, S.A.; Orenstein, J.; Kapitulnik, A.

2011-11-08T23:59:59.000Z

196

General Compression Looks at Energy Storage from a Different Angle |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

General Compression Looks at Energy Storage from a Different Angle General Compression Looks at Energy Storage from a Different Angle General Compression Looks at Energy Storage from a Different Angle February 3, 2011 - 3:36pm Addthis Image of the General Compression CAES system | courtesy of General Compression, Inc. Image of the General Compression CAES system | courtesy of General Compression, Inc. April Saylor April Saylor Former Digital Outreach Strategist, Office of Public Affairs Earlier this week, we told you about a new company that's developing battery technology that will allow energy storage for multiple hours on the power grid. General Compression is another innovative company that's developing a different way to store electricity by using compressed air energy storage, or CAES. The technology uses cheap power to pump air into

197

Correlation of conductivity and angle integrated valence band photoemission  

NLE Websites -- All DOE Office Websites (Extended Search)

Correlation of conductivity and angle integrated valence band photoemission Correlation of conductivity and angle integrated valence band photoemission characteristics in single crystal iron perovskites for 300 K < T < 800 K: Comparison of surface and bulk sensitive methods Title Correlation of conductivity and angle integrated valence band photoemission characteristics in single crystal iron perovskites for 300 K < T < 800 K: Comparison of surface and bulk sensitive methods Publication Type Journal Article Year of Publication 2010 Authors Braun, Artur, Bongjin S. Mun, Yun Sun, Z. Liu, Oliver Gröning, R. Mäder, Selma Erat, Xueyuan Zhang, Samuel S. Mao, Ekaterina Pomjakushina, Kazimierz Conder, and Thomas Graule Journal Journal of Electron Spectroscopy and Related Phenomena Volume 181 Issue 1 Pagination 56-62 Date Published 07/2013

198

Minimal Neutrino Texture with Neutrino Mass Ratio and Cabibbo Angle  

E-Print Network (OSTI)

We present neutrino mass matrix textures in a minimal framework of the type-I seesaw mechanism where two right-handed Majorana neutrinos are introduced in order to reproduce experimental results of neutrino oscillations. The textures can lead to experimentally favored leptonic mixing angles described by the tri-bimaximal mixing with one additional rotation. We present minimal and next to minimal textures for the normal mass hierarchy case in a context of the texture zero. A minimal texture in the inverted hierarchy case is also constructed, which does not have any vanishing entries in a Dirac neutrino mass matrix. We also discuss some cases that model parameters in the textures are supposed to be a neutrino mass ratio and/or the Cabibbo angle. Predicted regions of mixing angles, a leptonic CP-violation parameter, and an effective mass for the neutrino-less double beta decay are presented in all textures.

Yusuke Shimizu; Ryo Takahashi; Morimitsu Tanimoto

2012-12-24T23:59:59.000Z

199

General Compression Looks at Energy Storage from a Different Angle |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

General Compression Looks at Energy Storage from a Different Angle General Compression Looks at Energy Storage from a Different Angle General Compression Looks at Energy Storage from a Different Angle February 3, 2011 - 3:36pm Addthis Image of the General Compression CAES system | courtesy of General Compression, Inc. Image of the General Compression CAES system | courtesy of General Compression, Inc. April Saylor April Saylor Former Digital Outreach Strategist, Office of Public Affairs Earlier this week, we told you about a new company that's developing battery technology that will allow energy storage for multiple hours on the power grid. General Compression is another innovative company that's developing a different way to store electricity by using compressed air energy storage, or CAES. The technology uses cheap power to pump air into

200

PHASE DETECTOR  

DOE Patents (OSTI)

A phase detector circuit is described for use at very high frequencies of the order of 50 megacycles. The detector circuit includes a pair of rectifiers inverted relative to each other. One voltage to be compared is applied to the two rectifiers in phase opposition and the other voltage to be compared is commonly applied to the two rectifiers. The two result:ng d-c voltages derived from the rectifiers are combined in phase opposition to produce a single d-c voltage having amplitude and polarity characteristics dependent upon the phase relation between the signals to be compared. Principal novelty resides in the employment of a half-wave transmission line to derive the phase opposing signals from the first voltage to be compared for application to the two rectifiers in place of the transformer commonly utilized for such purpose in phase detector circuits for operation at lower frequency.

Kippenhan, D.O.

1959-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Off-Angle Iris Correction using a Biological Model  

SciTech Connect

This work implements an eye model to simulate corneal refraction effects. Using this model, ray tracing is performed to calculate transforms to remove refractive effects in off-angle iris images when reprojected to a frontal view. The correction process is used as a preprocessing step for off-angle iris images for input to a commercial matcher. With this method, a match score distribution mean improvement of 11.65% for 30 degree images, 44.94% for 40 degree images, and 146.1% improvement for 50 degree images is observed versus match score distributions with unmodi ed images.

Thompson, Joseph T [ORNL; Santos-Villalobos, Hector J [ORNL; Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

2013-01-01T23:59:59.000Z

202

PJMRprobe for dynamic-angle spinning K. T. Mueller, G. C. Chingas, and A. Pines  

E-Print Network (OSTI)

with a pulley attached to the probehead and coupled to a stepping motor outside of the magnet. The choice of a superconducting magnet. This allows the refocusing of nuclear spin magnetization that evolves under anisotropic of motor and gear ratio is based on an analysis of the moments of inertia of the motor and load

Pines, Alexander

203

Diffusion and adsorption of methane confined in nanoporous carbon aerogel: a combined quasi-elastic and small-angle neutron scattering study  

SciTech Connect

The diffusion of methane confined in nano-porous carbon aerogel with the average pore size 48 {angstrom} and porosity 60% was investigated as a function of pressure at T = 298 K using quasi-elastic neutron scattering (QENS). The diffusivity of methane shows a clear effect of confinement: it is about two orders of magnitude lower than in bulk at the same thermodynamic conditions and is close to the diffusivity of liquid methane at 100 K (i.e. {approx} 90 K below the liquid-gas critical temperature T{sub C} {approx} 191 K). The diffusion coefficient (D) of methane initially increases with pressure by a factor of {approx}2.5 from 3.47 {+-} 0.41 x 10{sup -10} m{sup 2} s{sup -1} at 0.482 MPa to D = 8.55 {+-} 0.33 x 10{sup -10} m{sup 2} s{sup -1} at 2.75 MPa and starts to decrease at higher pressures. An explanation of the observed non-monotonic behavior of the diffusivity in the confined fluid is based on the results of small-angle neutron scattering experiments of the phase behavior of methane in a similar carbon aerogel sample. The initial increase of the diffusion coefficient with pressure is explained as due to progressive filling of bigger pores in which molecular mobility in the internal pore volume is less affected by the sluggish liquid-like molecular mobility in the adsorbed phase. Subsequent decrease of D, is associated with the effect of intermolecular collisions, which result in a lower total molecular mobility with pressure, as in the bulk state. The results are compared with the available QENS data on the methane diffusivity in zeolites, metal organic frameworks, and porous silica as well as with the molecular dynamics simulations of methane in nano-porous carbons and silica zeolites.

Mavila Chathoth, Suresh [ORNL; Mamontov, Eugene [ORNL; Melnichenko, Yuri B [ORNL; Zamponi, Michaela M [ORNL

2010-01-01T23:59:59.000Z

204

Wind Turbine Pitch Angle Controllers for Grid Frequency Stabilisation  

E-Print Network (OSTI)

Wind Turbine Pitch Angle Controllers for Grid Frequency Stabilisation Clemens Jauch Risø National Laboratory Wind Energy Department P.O. Box 49 DK-4000 Roskilde, Denmark clemens.jauch@risoe.dk Abstract: In this paper it is investigated how active-stall wind turbines can contribute to the stabilisation of the power

205

Numerical Simulation of Katabatic Flow with Changing Slope Angle  

Science Conference Proceedings (OSTI)

A large eddy simulation (LES) model and the Advanced Regional Prediction System (ARPS) model, which does not resolve turbulent eddies, are used to study the effect of a slope angle decrease on the structure of katabatic slope flows. For a simple, ...

Craig M. Smith; Eric D. Skyllingstad

2005-11-01T23:59:59.000Z

206

SSM/I Brightness Temperature Corrections for Incidence Angle Variations  

Science Conference Proceedings (OSTI)

The incidence angles of the SSM/I radiometers on the DMSP satellites vary from satellite to satellite and exhibit variations of up to 1.5 during one orbit. The effects of these variations on the measured brightness temperatures are investigated ...

Rolf Fuhrhop; Clemens Simmer

1996-02-01T23:59:59.000Z

207

Neutrino Mass Models: Impact of non-zero reactor angle  

E-Print Network (OSTI)

In this talk neutrino mass models are reviewed and the impact of a non-zero reactor angle and other deviations from tri-bimaximal mixing are discussed. We propose some benchmark models, where the only way to discriminate between them is by high precision neutrino oscillation experiments.

Stephen F. King

2011-06-21T23:59:59.000Z

208

The Estimation of Wind Turbine Pitch Angle Based on ANN  

Science Conference Proceedings (OSTI)

Variable-speed and constant-frequency (VSCF) pitch-controlled wind turbine is believed to be superior to other types of wind turbine due to its features such as high efficiency and ideal starting and braking performance, Artificial Neural Networks (ANN) ... Keywords: VSCF, ANN, pitch angle, Pitch-controlled system

Yanping Liu; Shuhong Liu; Hongmei Guo; Huajun Wang

2009-11-01T23:59:59.000Z

209

Rapid emission angle selection for rotating-shield brachytherapy  

SciTech Connect

Purpose: The authors present a rapid emission angle selection (REAS) method that enables the efficient selection of the azimuthal shield angle for rotating shield brachytherapy (RSBT). The REAS method produces a Pareto curve from which a potential RSBT user can select a treatment plan that balances the tradeoff between delivery time and tumor dose conformity. Methods: Two cervical cancer patients were considered as test cases for the REAS method. The RSBT source considered was a Xoft Axxent{sup TM} electronic brachytherapy source, partially shielded with 0.5 mm of tungsten, which traveled inside a tandem intrauterine applicator. Three anchor RSBT plans were generated for each case using dose-volume optimization, with azimuthal shield emission angles of 90 Degree-Sign , 180 Degree-Sign , and 270 Degree-Sign . The REAS method converts the anchor plans to treatment plans for all possible emission angles by combining neighboring beamlets to form beamlets for larger emission angles. Treatment plans based on exhaustive dose-volume optimization (ERVO) and exhaustive surface optimization (ERSO) were also generated for both cases. Uniform dwell-time scaling was applied to all plans such that that high-risk clinical target volume D{sub 90} was maximized without violating the D{sub 2cc} tolerances of the rectum, bladder, and sigmoid colon. Results: By choosing three azimuthal emission angles out of 32 potential angles, the REAS method performs about 10 times faster than the ERVO method. By setting D{sub 90} to 85-100 Gy{sub 10}, the delivery times used by REAS generated plans are 21.0% and 19.5% less than exhaustive surface optimized plans used by the two clinical cases. By setting the delivery time budget to 5-25 and 10-30 min/fx, respectively, for two the cases, the D{sub 90} contributions for REAS are improved by 5.8% and 5.1% compared to the ERSO plans. The ranges used in this comparison were selected in order to keep both D{sub 90} and the delivery time within acceptable limits. Conclusions: The REAS method enables efficient RSBT treatment planning and delivery and provides treatment plans with comparable quality to those generated by exhaustive replanning with dose-volume optimization.

Liu, Yunlong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Sun, Wenqing [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Yang Wenjun [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa 52242 (United States); Wu Xiaodong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

2013-05-15T23:59:59.000Z

210

Asymmetric-cut variable-incident-angle monochromator  

Science Conference Proceedings (OSTI)

A novel asymmetric-cut variable-incident-angle monochromator was constructed and tested in 1997 at the Advanced Photon Source of Argonne National Laboratory. The monochromator was originally designed as a high heat load monochromator capable of handling 5-10 kW beams from a wiggler source. This was accomplished by spreading the x-ray beam out on the surface an asymmetric-cut crystal and by using liquid metal cooling of the first crystal. The monochromator turned out to be a highly versatile monochromator that could perform many different types of experiments. The monochromator consisted of two 18 deg. asymmetrically cut Si crystals that could be rotated about 3 independent axes. The first stage ({Phi}) rotates the crystal around an axis perpendicular to the diffraction plane. This rotation changes the angle of the incident beam with the surface of the crystal without changing the Bragg angle. The second rotation ({Psi}) is perpendicular to the first and is used to control the shape of the beam footprint on the crystal. The third rotation ({Theta}) controls the Bragg angle. Besides the high heat load application, the use of asymmetrically cut crystals allows one to increase or decrease the acceptance angle for crystal diffraction of a monochromatic x-ray beam and allows one to increase or decrease the wavelength bandwidth of the diffraction of a continuum source like a bending-magnet beam or a normal x-ray-tube source. When the monochromator is used in the doubly expanding mode, it is possible to expand the vertical size of the double-diffracted beam by a factor of 10-15. When this was combined with a bending magnet source, it was possible to generate an 8 keV area beam, 16 mm wide by 26 mm high with a uniform intensity and parallel to 1.2 arc sec that could be applied in imaging experiments.

Smither, R. K.; Fernandez, P. B.; Mills, D. M. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Graber, T. J. [Center for Advanced Radiation Sources, University of Chicago, Chicago, Illinois 60637 (United States)

2012-03-15T23:59:59.000Z

211

Phase-Field Modeling of Microstructure Evolution in Elastically ...  

Science Conference Proceedings (OSTI)

... and lithium-depleted two-phase mixtures in Li-intercalation compounds, and evolution ... Ab Initio Temperature-Dependent Lattice Dynamics for BCC Uranium .

212

Nodal domains of a non-separable problem - the right angled isosceles triangle  

E-Print Network (OSTI)

We study the nodal set of eigenfunctions of the Laplace operator on the right angled isosceles triangle. A local analysis of the nodal pattern provides an algorithm for computing the number of nodal domains for any eigenfunction. In addition, an exact recursive formula for the number of nodal domains is found to reproduce all existing data. Eventually we use the recursion formula to analyse a large sequence of nodal counts statistically. Our analysis shows that the distribution of nodal counts for this triangular shape has a much richer structure than the known cases of regular separable shapes or completely irregular shapes. Furthermore we demonstrate that the nodal count sequence contains information about the periodic orbits of the corresponding classical ray dynamics.

Amit Aronovitch; Ram Band; David Fajman; Sven Gnutzmann

2011-10-07T23:59:59.000Z

213

The Large-Angle Photon Veto System for the NA62 Experiment at CERN  

E-Print Network (OSTI)

AbstractThe branching ratio (BR) for the decay K + ? ? + ? ? is a sensitive probe for new physics. The NA62 experiment at the CERN SPS will measure this BR to within about 10%. To reject the dominant background from channels with final state photons, the large-angle vetoes (LAVs) must detect photons of energy as low as 200 MeV with an inefficiency of less than 10 ?4, as well as provide energy and time measurements with resolutions of 10 % and 1 ns for 1 GeV photons. The LAV detectors make creative reuse of lead glass blocks recycled from the OPAL electromagnetic calorimeter barrel. We describe the mechanical design and challenges faced during construction, the characterization of the lead glass blocks and solutions adopted for monitoring their performance, and the development of front-end electronics to allow simultaneous time and energy measurements over an extended dynamic range using the time-over-threshold

F. Ambrosino; B. Angelucci; A. Antonelli; F. Costantini; R. Fantechi; S. Gallorini; S. Giudici; E. Leonardi; I. Mannelli; P. Massarotti; M. Moulson; M. Napolitano; V. Palladino; F. Rafaelli; M. Raggi; G. Saracino; M. Serra; T. Spadaro; P. Valente; S. Venditti; F. Ambrosino; P. Massarotti; M. Napolitano

2011-01-01T23:59:59.000Z

214

Quantum gates and their coexisting geometric phases  

SciTech Connect

Geometric phases arise naturally in a variety of quantum systems with observable consequences. They also arise in quantum computations when dressed states are used in gating operations. Here we show how they arise in these gating operations and how one may take advantage of the dressed states producing them. Specifically, we show that for a given, but arbitrary Hamiltonian, and at an arbitrary time {tau}, there always exists a set of dressed states such that a given gate operation can be performed by the Hamiltonian up to a phase {phi}. The phase is a sum of a dynamical phase and a geometric phase. We illustrate the dressed phase for several systems.

Wu Lianao [Ikerbasque, Basque Foundation for Science, E-48011 Bilbao (Spain); Department of Theoretical Physics and History of Science, Basque Country University (EHU/UPV), P.O. Box 644, E-48080 Bilbao (Spain); Bishop, C. Allen [Physics Department, Southern Illinois University, Carbondale, Illinois 62901-4401 (United States); Byrd, Mark S. [Physics Department, Southern Illinois University, Carbondale, Illinois 62901-4401 (United States); Computer Science Department, Southern Illinois University, Carbondale, Illinois 62901 (United States)

2011-08-15T23:59:59.000Z

215

Toroidal Precession as a Geometric Phase  

SciTech Connect

Toroidal precession is commonly understood as the orbit-averaged toroidal drift of guiding centers in axisymmetric and quasisymmetric configurations. We give a new, more natural description of precession as a geometric phase effect. In particular, we show that the precession angle arises as the holonomy of a guiding center's poloidal trajectory relative to a principal connection. The fact that this description is physically appropriate is borne out with new, manifestly coordinate-independent expressions for the precession angle that apply to all types of orbits in tokamaks and quasisymmetric stellarators alike. We then describe how these expressions may be fruitfully employed in numerical calculations of precession.

J.W. Burby and H. Qin

2012-09-26T23:59:59.000Z

216

Critical dynamics and decoherence  

SciTech Connect

We study dynamics of decoherence in a generic model where the environment is driven and undergoes a quantum phase transition. We model the environment by the Ising chain in the transverse field, and assume that the decohering system is a central spin-1/2. We found that when the environment is quenched slowly through the critical point, the decoherence factor of the central spin undergoes rapid decay that encodes the critical exponents of the environment. We also found that decoherence in a non-equilibrated, kink-contaminated, environment can be stronger than in a vacuum one. We derived a remarkably simple analytical expression that describes post-transition decoherence and predicts periodicities involving all system parameters. This research connects the fields of decoherence, quantum phase transitions, and Kibble-Zurek non-equilibrium dynamics.

Damski, Bogdan [Los Alamos National Laboratory; Quan, Haitao T [Los Alamos National Laboratory; Zurek, Wojciech H [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

217

Phase Transformations  

Science Conference Proceedings (OSTI)

Aug 9, 2013 ... O. Advanced Neutron and Synchrotron Studies of Materials: Phase .... We will describe recent advances at the Advanced Photon Source in ... Finally, we will describe upgrade plans for microdiffraction capabilities at the APS.

218

Searching for the Neutrino Mixing Angle Theta-13 at Reactors  

E-Print Network (OSTI)

Two neutrino mixing angles have been measured, and much of the neutrino community is turning its attention to the unmeasured mixing angle, $\\quq$, whose best limit comes from the reactor neutrino experiment CHOOZ.\\cite{bib:chooz} New two detector reactor neutrino experiments are being planned, along with more ambitious accelerator experiments, to measure or further limit $\\quq$. Here I will overview how to measure $\\quq$ using reactor neutrinos, mention some experiments that were considered and are not going forward, and review the current status of four projects: Double Chooz in France, Daya Bay in China, RENO in South Korea and Angra in Brazil. Finally I will mention how the neutrino observer can gauge progress in these projects two years from now as we approach the times corresponding to early estimates for new results.

Goodman, Maury

2007-01-01T23:59:59.000Z

219

Metal oxide morphology in argon-assisted glancing angle deposition  

Science Conference Proceedings (OSTI)

Glancing angle deposition (GLAD) is a thin film deposition technique capable of fabricating columnar architectures such as posts, helices, and chevrons with control over nanoscale film features. Argon bombardment during deposition modifies the GLAD process, producing films with new morphologies which have shown promise for sensing and photonic devices. The authors report modification of column tilt angle, film density, and specific surface area for 12 different metal oxide and fluoride film materials deposited using Ar-assisted GLAD. For the vapor flux/ion beam geometry and materials studied here, with increasing argon flux, the column tilt increases, film density increases, and specific surface area decreases. With a better understanding of the nature of property modification and the mechanisms responsible, the Ar-assisted deposition process can be more effectively targeted towards specific applications, including birefringent thin films or photonic crystal square spirals.

Sorge, J. B.; Taschuk, M. T.; Wakefield, N. G.; Sit, J. C.; Brett, M. J. [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 2V4 (Canada); Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 2V4 (Canada) and NRC National Institute for Nanotechnology, Edmonton, AB T6G 2M9 (Canada)

2012-03-15T23:59:59.000Z

220

A SMALL-ANGLE DRILL-HOLE WHIPSTOCK  

DOE Patents (OSTI)

A small angle whipstock is described for accurately correcting or deviating a drill hole by a very small angle. The whipstock is primarily utilized when drilling extremely accurate, line-of-slight test holes as required for diagnostic studies related to underground nuclear test shots. The invention is constructed of a length of cylindrical pipe or casing, with a whipstock seating spike extending from the lower end. A wedge-shaped segment is secured to the outer circumference of the upper end of the cylinder at a position diametrically opposite the circumferential position of the spike. Pin means are provided for affixing the whipstock to a directional drill bit and stem to alloy orienting and setting the whipstock properly in the drill hole. (AEC)

Nielsen, D.E.; Olsen, J.L.; Bennett, W.P.

1963-01-29T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Angle amplifying optics using plane and ellipsoidal reflectors  

DOE Patents (OSTI)

An optical system for providing a wide angle input beam into ellipsoidal laser fusion target illumination systems. The optical system comprises one or more pairs of centrally apertured plane and ellipsoidal mirrors disposed to accept the light input from a conventional lens of modest focal length and thickness, to increase the angular divergence thereof to a value equivalent to that of fast lenses, and to direct the light into the ellipsoidal target illumination system.

Glass, Alexander J. (Pleasanton, CA)

1977-01-01T23:59:59.000Z

222

NA Standards | Valence Geometries | Bond Angles-Furanose Rings  

NLE Websites -- All DOE Office Websites (Extended Search)

angles in Furanose Rings angles in Furanose Rings ----------------------------------------------------- ribose deoxyribose ----------------------------------------------------- angle mean esd N mean esd N value value ----------------------------------------------------- C1'-C2'-C3' 101.5 (0.9, 80) 102.7 (1.4, 47) C2'-C3'-C4' 102.7 (1.0, 80) 103.2 (1.0, 47) C3'-C4'-O4' 105.5 (1.4, 80) 105.6 (1.0, 47) C4'-O4'-C1' 109.6 (0.9, 80) 109.7 (1.4, 47) O4'-C1'-C2' 106.4 (1.4, 80) 106.1 (1.0, 47) C1'-C2'-O2' 110.6 (3.0, 80) na C3'-C2'-O2' 113.3 (2.9, 80) na C2'-C3'-O3' 111.0 (2.8, 80) 110.6 (2.7, 47) C4'-C3'-O3' 110.6 (2.6, 80) 110.3 (2.2, 47) C5'-C4'-C3' 115.5 (1.5, 80) 114.7 (1.5, 47)

223

On-demand generation of aqueous two-phase microdroplets with reversible phase transitions  

Science Conference Proceedings (OSTI)

Aqueous two-phase systems contained entirely within microdroplets enable a bottom-up approach to mimicking the dynamic microcompartmentation of biomaterial that naturally occurs within the cytoplasm of cells. Here, we demonstrate the on-demand generation of femtolitre aqueous two-phase droplets within a microfluidic oil channel. Gated pressure pulses were used to generate individual, stationary two-phase microdroplets with a well-defined time zero for carrying out controlled and sequential phase transformations over time. Reversible phase transitions between single-phase, two-phase, and core-shell microgel states were obtained via evaporation-induced dehydration and on-demand water rehydration. In contrast to other microfluidic aqueous two-phase droplets, which require continuous flows and high-frequency droplet formation, our system enables the controlled isolation and reversible transformation of a single microdroplet and is expected to be useful for future studies in dynamic microcompartmentation and affinity partitioning.

Boreyko, Jonathan B [ORNL; Mruetusatorn, Prachya [ORNL; Retterer, Scott T [ORNL; Collier, Pat [ORNL

2013-01-01T23:59:59.000Z

224

HYDROGEN AND DEUTERIUM NMR OF SOLIDS BY MAGIC ANGLE SPINNING  

DOE Green Energy (OSTI)

The nuclear magnetic resonance of solids has long been characterized by very large spectral broadening which arises from internuclear dipole-dipole coupling or the nuclear electric quadrupole interaction. These couplings can obscure the smaller chemical shift interaction and make that information unavailable. Two important and difficult cases are that of hydrogen and deuterium. For example, the homonuclear dipolar broadening, HD, for hydrogen is usually several tens of kilohertz. For deuterium, HD is relatively small; however, the quadrupole interaction causes a broadening which can be hundreds of kilohertz in polycrystalline or amorphous solids. The development of cross polarization, heteronuclear radiofrequency decoupling, and coherent averaging of nuclear spin interactions has provided measurement of chemical shift tensors in solids. Recently, double quantum NMR and double quantum decoupling have led to measurement of deuterium and proton chemical shift tensors, respectively. A general problem of these experiments is the overlapping of the tensor powder pattern spectra of magnetically distinct sites which cannot be resolved. In this work, high resolution NMR of hydrogen and deuterium in solids is demonstrated. For both nuclei, the resonances are narrowed to obtain liquid-like isotropic spectra by high frequency rotation of the sample about an axis inclined at the magic angle, {beta}{sub m} = Arccos(3{sup -1/2}), with respect to the direction of the external magnetic field. Two approaches have been developed for each nucleus. For deuterium, the powder spectra were narrowed by over three orders of magnitude by magic angle rotation with precise control of {beta}. A second approach was the observation of deuterium double quantum transitions under magic angle rotation. For hydrogen, magic angle rotation alone could be applied to obtain the isotropic spectrum when H{sub D} was small. This often occurs naturally when the nuclei are semi-dilute or involved in internal motion. In the general case of large H{sub D}, isotropic spectra were obtained by dilution of {sup 1}H with {sup 2}H combined with magic angle rotation. The resolution obtained represents the practical limit for proton NMR of solids. Theoretical and technical aspects are described in the text with comments on the application of the principles to other nuclei of interest.

Eckman, R.R.

1982-10-01T23:59:59.000Z

225

Dislocation Dynamics  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Recent Progress in Dislocation Dynamics: Sylvie Aubry1; Athanasios Arsenlis1; Wei Cai2; Steve Fitzgerald3; 1LLNL; 2Stanford University;...

226

Phase response characteristics of sinoatrial node cells  

Science Conference Proceedings (OSTI)

In this work, the dynamic response of the sinoatrial node (SAN), the natural pacemaker of the heart, to short external stimuli is investigated using the Zhang et al. model. The model equations are solved twice for the central cell and for the peripheral ... Keywords: Cardiac models, Heart, Mathematical models, Phase resetting, Regional differences, Sinoatrial node, Three-dimensional phase transition curves

D. G. Tsalikakis; H. G. Zhang; D. I. Fotiadis; G. P. Kremmydas; ?. K. Michalis

2007-01-01T23:59:59.000Z

227

18.385 Nonlinear Dynamics and Chaos, Fall 2002  

E-Print Network (OSTI)

Nonlinear dynamics with applications. Intuitive approach with emphasis on geometric thinking, computational and analytical methods. Extensive use of demonstration software. Topics: Bifurcations. Phase plane. Nonlinear ...

Rosales, Rodolfo

228

Quantum phases of dipolar spinor condensates  

E-Print Network (OSTI)

We study the zero-temperature ground state structure of a spin-1 condensate with magnetic dipole-dipole interactions. We show that the dipolar interactions break the rotational symmetry of the Hamiltonian and induce new quantum phases. Different phases can be reached by tuning the effective strength of the dipolar interactions via modifying the trapping geometry. The experimental feasibility of detecting these phases is investigated. The spin-mixing dynamics is also studied.

S. Yi; L. You; H. Pu

2004-05-21T23:59:59.000Z

229

Weinberg Angle and Integer Electric Charges of Quarks  

E-Print Network (OSTI)

Orthogonality between photon and Z boson involves the Weinberg angle and a scheme for assignments of electric charge and weak isospin to leptons and quarks coupling to photon and Z. The Han-Nambu scheme, with integer electric charges for quarks, satisfies photon-Z orthogonality with sin^2(theta_W)= 0.25 in leading order. Experimental results for photon-photon fusion into charm-anticharm and bottom-antibottom pairs provide further support for assigning integer electric charges to quarks.

Martin A. Faessler

2013-08-22T23:59:59.000Z

230

Estimation of the Aerosol Phase Function in Backscatter from Simultaneous Satellite and Sun-Photometer Measurements  

Science Conference Proceedings (OSTI)

The backscatter part of the aerosol phase function PA(?), where ? is the scattering angle, is difficult to measure from the ground. Experimental data for ? > 120 are not reported in the literature. Customarily, PA(?) is calculated from Mie ...

Alexander Ignatov

1997-06-01T23:59:59.000Z

231

Double wells, scalar fields and quantum phase transitions in ions traps  

E-Print Network (OSTI)

Since Hund's work on the ammonia molecule, the double well potential has formed a key paradigm in physics. Its importance is further underlined by the central role it plays in the Landau theory of phase transitions. Recently, the study of entanglement properties of many-body systems has added a new angle to the study of quantum phase transitions of discrete and continuous degrees of freedom, i.e., spin and harmonic chains. Here we show that control of the radial degree of freedom of trapped ion chains allows for the simulation of linear and non-linear Klein-Gordon fields on a lattice, in which the parameters of the lattice, the non-linearity and mass can be controlled at will. The system may be driven through a phase transition creating a double well potential between different configurations of the ion crystal. The dynamics of the system are controllable, local properties are measurable and tunnelling in the double well potential would be observable.

A. Retzker; R. Thompson; D. Segal; M. B. Plenio

2008-01-04T23:59:59.000Z

232

Two-phase flow studies  

DOE Green Energy (OSTI)

The two-phase flow program is directed at understanding the hydrodynamics of two-phase flows. The two-phase flow regime is characterized by a series of flow patterns that are designated as bubble, slug, churn, and annular flow. Churn flow has received very little scientific attention. This lack of attention cannot be justified because calculations predict that the churn flow pattern will exist over a substantial portion of the two-phase flow zone in producing geothermal wells. The University of Houston is experimentally investigating the dynamics of churn flow and is measuring the holdup over the full range of flow space for which churn flow exists. These experiments are being conducted in an air/water vertical two-phase flow loop. Brown University has constructed and is operating a unique two-phase flow research facility specifically designed to address flow problems of relevance to the geothermal industry. An important feature of the facility is that it is dedicated to two-phase flow of a single substance (including evaporation and condensation) as opposed to the case of a two-component two-phase flow. This facility can be operated with horizontal or vertical test sections of constant diameter or with step changes in diameter to simulate a geothermal well profile.

Hanold, R.J.

1983-12-01T23:59:59.000Z

233

The small mixing angle {theta}13 and the lepton asymmetry  

SciTech Connect

We present the correlation of low energy CP phases, and the lepton asymmetry for the baryon asymmetry in the universe, for cases in which the amount of the lepton asymmetry YL turns out to be proportional to {theta}{sub 13}{sup 2}, considering the constraint between two types of CP phases and the relation of YL versus the Jarlskog invariant or the amplitude of neutrinoless double beta decay as {theta}13 varies.

Lee, Song-Haeng; Siyeon, Kim [Department of Physics, Chung-Ang University, Seoul 156-756 (Korea, Republic of)

2005-12-02T23:59:59.000Z

234

The reactor mixing angle and CP violation with two texture zeros in the light of T2K  

E-Print Network (OSTI)

We reconsider the phenomenological implications of two texture zeros in symmetric neutrino mass matrices in the light of the recent T2K result for the reactor angle and the new global analysis which gives also best fit values for the Dirac CP phase delta. The most important results of the analysis are: Among the viable cases classified by Frampton et al. only A1 and A2 predict the reactor mixing angle to be different from zero at 3 sigma. Furthermore these two cases are compatible only with a normal mass spectrum in the allowed region for the reactor angle. At the best fit value A1 and A2 predict 0.024 >= sin^2(theta13) >= 0.012 and 0.014 <= sin^2(theta13) <= 0.032, respectively, where the bounds on the right and the left correspond to cos(delta)=-1 and cos(delta)=1, respectively. The cases B1, B2, B3 and B4 predict nearly maximal CP violation, i.e. cos(delta) is approximately zero.

P. O. Ludl; S. Morisi; E. Peinado

2011-09-15T23:59:59.000Z

235

NON-LINEAR DYNAMICS IDENTIFICATION USING  

E-Print Network (OSTI)

to be identified and extracted from the data. The above work is applied to a real physical wind turbine data 143 5 Case Study: Identification of Wind Turbine Dynamics Using Gaussian Processes 145 5 Turbine Dynamics 147 5.3.1 About the Data 148 5.3.2 Cleaning Up Raw Data (Phase 1) 152 5.3.3 Nonlinear

Duffy, Ken

236

Rotation Angle for the Optimum Tracking of One-Axis Trackers  

DOE Green Energy (OSTI)

An equation for the rotation angle for optimum tracking of one-axis trackers is derived along with equations giving the relationships between the rotation angle and the surface tilt and azimuth angles. These equations are useful for improved modeling of the solar radiation available to a collector with tracking constraints and for determining the appropriate motor revolutions for optimum tracking.

Marion, W. F.; Dobos, A. P.

2013-07-01T23:59:59.000Z

237

ERROR ESTIMATES FOR FINITE DIFFERENCE METHODS FOR A WIDE-ANGLE `PARABOLIC' EQUATION  

E-Print Network (OSTI)

ERROR ESTIMATES FOR FINITE DIFFERENCE METHODS FOR A WIDE-ANGLE `PARABOLIC' EQUATION G. D. AKRIVIS-value problem for a third-order p.d.e., a wide-angle `parabolic' equation frequently used in underwater. wide-angle `parabolic' equation, Underwater Acoustics, finite difference error esti- mates, interface

Akrivis, Georgios

238

Identification and modeling for non-linear dynamic system using neural networks type MLP  

Science Conference Proceedings (OSTI)

In control systems, the model dynamics of linear systems is the principal and most important phase of a project, but when working with dynamic of non-linear systems obtain the model becomes a very complex task can be used techniques of system identification. ... Keywords: LP, algorithms, dynamic backprogation, modeling, multilayer perceptrons, neural networks dynamics, non-linear dynamics, training

Hernn Gonzlez Acua; Max Suell Dutra; Omar Lengerke

2009-06-01T23:59:59.000Z

239

Small-angle x-ray scattering measurements of the microstructure of liquid helium mixtures adsorbed in aerogel  

Science Conference Proceedings (OSTI)

Small-angle x-ray scattering (SAXS) was used to measure the microstructure of isotopic mixtures of {sup 3}He and {sup 4}He adsorbed into silica aerogels as a function of temperature and {sup 3}He concentration. The SAXS measurements could be well described by the formation of a nearly pure film of {sup 4}He which separates from the bulk mixture onto the aerogel strands and which thickens with decreasing temperature. Previous observations of a superfluid {sup 3}He-rich phase are consistent with superfluidity existing within this film phase. Observed differences between different density aerogels are explained in terms of the depletion of {sup 4}He from the bulk mixture due to film formation.

Lurio, L. B.; Mulders, N.; Paetkau, M.; Chan, M. H. W.; Mochrie, S. G. J. [Department of Physics, Northern Illinois University, DeKalb, Illinois 60115 (United States); Department of Physics, University of Delaware, Newark, Delaware 19716 (United States); Department of Physics and Astronomy, Okanagan College, British Columbia V1Y4X8 (Canada); Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Department of Physics, Yale University, New Haven, Connecticut 06511 (United States)

2007-07-15T23:59:59.000Z

240

A unified analysis of the reactor neutrino program towards the measurement of the theta_13 mixing angle  

E-Print Network (OSTI)

We present in this article a detailed quantitative discussion of the measurement of the leptonic mixing angle theta_13 through currently scheduled reactor neutrino oscillation experiments. We thus focus on Double Chooz (Phase I & II), Daya Bay (Phase I & II) and RENO experiments. We perform a unified analysis, including systematics, backgrounds and accurate experimental setup in each case. Each identified systematic error and background impact has been assessed on experimental setups following published data when available and extrapolating from Double Chooz acquired knowledge otherwise. After reviewing the experiments, we present a new analysis of their sensitivities to sin^2(2 theta_13) and study the impact of the different systematics based on the pulls approach. Through this generic statistical analysis we discuss the advantages and drawbacks of each experimental setup.

Guillaume Mention; Thierry Lasserre; Dario Motta

2007-04-04T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

A swollen phase observed between the liquid-crystalline phase and the interdigitated phase induced by pressure and/or adding ethanol in DPPC aqueous solution  

E-Print Network (OSTI)

A swollen phase, in which the mean repeat distance of lipid bilayers is larger than the other phases, is found between the liquid-crystalline phase and the interdigitated gel phase in DPPC aqueous solution. Temperature, pressure and ethanol concentration dependences of the structure were investigated by small-angle neutron scattering, and a bending rigidity of lipid bilayers was by neutron spin echo. The nature of the swollen phase is similar to the anomalous swelling reported previously. However, the temperature dependence of the mean repeat distance and the bending rigidity of lipid bilayers are different. This phase could be a precursor to the interdigitated gel phase induced by pressure and/or adding ethanol.

H. Seto; M. Hishida; H. Nobutou; N. L. Yamada; M. Nagao; T. Takeda

2006-02-21T23:59:59.000Z

242

Lower hybrid instability driven by mono-energy {alpha}-particles with finite pitch angle spread in a plasma  

Science Conference Proceedings (OSTI)

A kinetic formalism of lower hybrid wave instability, driven by mono-energy {alpha}-particles with finite pitch angle spread, is developed. The instability arises through cyclotron resonance interaction with high cyclotron harmonics of {alpha}-particles. The {alpha}-particles produced in D-T fusion reactions have huge Larmor radii ({approx}10 cm) as compared to the wavelength of the lower hybrid wave, whereas their speed is an order of magnitude smaller than the speed of light in vacuum. As a result, large parallel phase velocity lower hybrid waves, suitable for current drive in tokamak, are driven unstable via coupling to high cyclotron harmonics. The growth rate decreases with increase in pitch angle spread of the beam. At typical electron density of {approx}10{sup 19} m{sup -3}, magnetic field {approx}4 Tesla and {alpha}-particle concentration {approx}0.1%, the large parallel phase velocity lower hybrid wave grows on the time scale of 20 ion cyclotron periods. The growth rate decreases with plasma density.

Kumar, Pawan; Singh, Vishwesh; Tripathi, V. K. [Department of Physics, IIT Delhi, New Delhi-110016 (India)

2013-02-15T23:59:59.000Z

243

Oxygen-diffusion limited metal combustions in Zr, Ti, and Fe foils: Time- and angle-resolved x-ray diffraction studies  

Science Conference Proceedings (OSTI)

The transient phase and chemical transformations of diffusion controlled metal combustions in bulk Zr, Ti, and Fe foils have been investigated, in situ, using novel time- and angle-resolved x-ray diffraction (TARXD). The TARXD employs monochromatic synchrotron x-rays and a fast-rotating diffracted beam chopper resolving the diffraction image temporally in time-resolution of {approx}45 {mu}s along the azimuth on a 2D pixel array detector. The metal foil strips (10-25 {mu}m in thickness) are ignited using a pulsed electrical heating with a typical heating rate of {approx}10{sup 6} K/s. The x-ray results indicate that the combustion occurs in molten metals, producing a wide range of stoichiometric solid oxides. It reflects an enhanced oxygen solubility and mobility of molten metals with respect to those of solid metals. However, the initial oxides formed are mainly oxygen-deficient metal oxides of ZrO, TiO, and FeO/Fe{sub 3}O{sub 4} - the lowest suboxides stable at these high temperatures. These transition metal monoxides further react with unreacted molten metals, yielding the secondary products of Zr{sub 3}O, Ti{sub 3}O, and Ti{sub 2}O - but not in FeO/Fe{sub 3}O{sub 4}. On the other hand, the higher stoichiometric oxides of ZrO{sub 2} and TiO{sub 2} are formed in the later time only on the metal surface. These results clearly indicate that the combustion process of metal strips is diffusion limited and strongly depends on the solubility and diffusivity of oxygen into molten metals. The time-resolved diffraction data reveals no evidence for metal oxidation in solids, but a series of temperature-induced polymorphic phase transitions. The dynamic thermal expansibility of Fe measured in the present fast heating experiments is similar to those in static conditions (3.3*10{sup -5}/K vs 3.5*10{sup -5}/K for {alpha}-Fe and 6.5*10{sup -5}/K versus 7.0*10{sup -5}/K for {gamma}-Fe).

Wei, Haoyan; Yoo, Choong-Shik; Chen, Jing-Yin; Shen, Guoyin (CIW); (WSU)

2012-04-30T23:59:59.000Z

244

Phase Conjugation in Quantum Optomechanics  

E-Print Network (OSTI)

We analyze the phase conjugate coupling of a pair of optomechanical oscillator modes driven by the time-dependent beat-note due to a two-color optical field. The dynamics of the direct and phase conjugate modes exhibit familiar time-reversed qualities, leading to opposite sign temperatures for the modes in the classical regime of operation, but these features are limited by quantum effects due to the non-commutative nature of quantum mechanical operators. The effects are measurable by read-out of the oscillator via a qubit. As a potential application of this system in sensing, we discuss a protocol applying phase-conjugate swaps to cancel external forces acting on the system.

L. F. Buchmann; E. M. Wright; P. Meystre

2013-05-08T23:59:59.000Z

245

Correlation of Oil-Water and Air-Water Contact Angles of Diverse Silanized Surfaces and Relationship to Fluid Interfacial Tensions  

Science Conference Proceedings (OSTI)

The use of air-water, {Theta}{sub wa}, or air-liquid contact angles is customary in surface science, while oil-water contact angles {Theta}{sub ow}, are of paramount importance in subsurface multiphase flow phenomena including petroleum reocovery, nonaqueous phase liquid fate and transport, and geological carbon sequestration. In this paper we determine both the air-water and oil-water contact angles of silica surfaces modified with a diverse selection of silanes, using hexadecane as the oil. The silanes included alkylsilanes, alkylarylsilanes, and silanes with alkyl or aryl groups that are functionalized with heteroatoms such as N, O, and S. These silanes yielded surfaces with wettabilities from water-wet to oil wet, including specific silanized surfaces functionalized with heteroatoms that yield intermediate wet surfaces. The oil-water contact angles for clean and silanized surfaces, excluding one partially fluorinated surface, correlate linearly with air-water contact angles with a slope of 1.41 (R = 0.981, n = 13). These data were used to examine a previously untested theoretical treatment relating air-water and oil-water contact angles in terms of fluid interfacial energies. Plotting the cosines of these contact angles against one another, we obtain a linear relationship in excellent agreement with the theoretical treatment; the data fit cos {Theta}{sub ow} = 0.667 cos {Theta}{sub ow} + 0.384 (R = 0.981, n = 13), intercepting cos {Theta}{sub ow} = -1 at -0.284. The theoretical slope, based on the fluid interfacial tensions {Theta}{sub wa}, {Theta}{sub ow}, and {Theta}{sub oa}, is 0.67. We also demonstrate how silanes can be used to alter the wettability of the interior of a pore network micromodel device constructed in silicon/silica with a glass cover plate. Such micromodels are used to study multiphase flow phenomena. The contact angle of the resulting interior was determined in situ. An intermediate wet micromodel gave a contact angle in excellent agreement with that obtained on an open planar silica surface using the same silane.

Grate, Jay W.; Dehoff, Karl J.; Warner, Marvin G.; Pittman, Jonathan W.; Wietsma, Thomas W.; Zhang, Changyong; Oostrom, Martinus

2012-02-24T23:59:59.000Z

246

NA Standards | Valence Geometries | Bond Lengths & Angles - Guanine  

NLE Websites -- All DOE Office Websites (Extended Search)

Guanine Guanine ---------------------------------------------------- Bond or Angle Mean (esd, N) Value ---------------------------------------------------- N1-C2 1.373 (0.008, 21) C2-N3 1.323 (0.008, 21) N3-C4 1.350 (0.007, 21) C4-C5 1.379 (0.007, 21) C5-C6 1.419 (0.010, 21) C6-N1 1.391 (0.007, 21) C5-N7 1.388 (0.006, 21) N7-C8 1.305 (0.006, 21) C8-N9 1.374 (0.007, 21) N9-C4 1.375 (0.008, 21) C2-N2 1.341 (0.010, 21) C6-O6 1.237 (0.009, 21) N9-C1' 1.459 (0.009, 21) C6-N1-C2 125.1 (0.6, 21) N1-C2-N3 123.9 (0.6, 21) C2-N3-C4 111.9 (0.5, 21) N3-C4-C5 128.6 (0.5, 21) C4-C5-C6 118.8 (0.6, 21) C5-C6-N1 111.5 (0.5, 21)

247

Angle stations in or for endless conveyor belts  

DOE Patents (OSTI)

In an angle station for an endless conveyor belt, there are presented to each incoming run of the belt stationary curved guide members (18, 19) of the shape of a major segment of a right-circular cylinder and having in the part-cylindrical portion (16 or 17) thereof rectangular openings (15) arranged in parallel and helical paths and through which project small freely-rotatable rollers (14), the continuously-changing segments of the curved surfaces of which projecting through said openings (15) are in attitude to change the direction of travel of the belt (13) through 90.degree. during passage of the belt about the part-cylindrical portion (16 or 17) of the guide member (18 or 19). The rectangular openings (15) are arranged with their longer edges lengthwise of the diagonals representing the mean of the helix but with those of a plurality of the rows nearest to each end of the part-cylindrical portion (16 or 17) slightly out of axial symmetry with said diagonals, being slightly inclined in a direction about the intersections (40) of the diagonals of the main portion of the openings, to provide a "toe-in" attitude in relation to the line of run of the endless conveyor belt.

Steel, Alan (Glasgow, GB6)

1987-04-07T23:59:59.000Z

248

NA Standards | Valence Geometries | Bond Lengths & Angles - Adenine  

NLE Websites -- All DOE Office Websites (Extended Search)

Adenine Adenine ---------------------------------------------------- Bond or Angle Mean (esd, N) Value ---------------------------------------------------- N1-C2 1.339 (0.009, 48) C2-N3 1.331 (0.009, 48) N3-C4 1.344 (0.006, 48) C4-C5 1.383 (0.007, 48) C5-C6 1.406 (0.009, 48) C6-N1 1.351 (0.007, 48) C5-N7 1.388 (0.006, 48) N7-C8 1.311 (0.007, 48) C8-N9 1.373 (0.008, 48) N9-C4 1.374 (0.006, 48) C6-N6 1.335 (0.008, 48) N9-C1' 1.462 (0.010, 48) C6-N1-C2 118.6 (0.6, 48) N1-C2-N3 129.3 (0.5, 48) C2-N3-C4 110.6 (0.5, 48) N3-C4-C5 126.8 (0.7, 48) C4-C5-C6 117.0 (0.5, 48) C5-C6-N1 117.7 (0.5, 48) C4-C5-N7 110.7 (0.5, 48) C5-N7-C8 103.9 (0.5, 48)

249

NA Standards | Valence Geometries | Bond Lengths & Angles - Protonated  

NLE Websites -- All DOE Office Websites (Extended Search)

Protonated Adenine Protonated Adenine ---------------------------------------------------- Bond or Angle Mean (esd, N) Value ---------------------------------------------------- N1-C2 1.357 (0.009, 15) C2-N3 1.305 (0.008, 15) N3-C4 1.356 (0.006, 15) C4-C5 1.378 (0.008, 15) C5-C6 1.403 (0.007, 15) C6-N1 1.359 (0.007, 15) C5-N7 1.379 (0.005, 15) N7-C8 1.312 (0.008, 15) C8-N9 1.373 (0.009, 15) N9-C4 1.365 (0.007, 15) C6-N6 1.320 (0.008, 15) N9-C1' 1.466 (0.009, 15) C6-N1-C2 123.3 (0.6, 15) N1-C2-N3 125.7 (0.6, 15) C2-N3-C4 111.6 (0.4, 15) N3-C4-C5 127.4 (0.6, 15) C4-C5-C6 117.9 (0.5, 15) C5-C6-N1 114.0 (0.4, 15) C4-C5-N7 111.0 (0.3, 15) C5-N7-C8 103.7 (0.4, 15)

250

Characterization of photosynthetic supramolecular assemblies using small angle neutron scattering  

DOE Green Energy (OSTI)

We are using small angle neutron scattering (SANS) to resolve structural features of supramolecular assemblies of photosynthetic proteins in liquid and frozen solutions. SANS resolves the size, shape, and structural homogeneity of macromolecular assemblies in samples identical to those used for spectroscopic assays of photosynthetic function. Likely molecular structures of the supramolecular assemblies can be identified by comparing experimental scattering data with scattering profiles calculated for model supramolecular assemblies built from crystal structures of the individual proteins. SANS studies of the Rhodobacter sphaeroides reaction center, RC, presented here, show that the detergent solubilized RC exists in a variety of monomeric and aggregation states. The distribution between monomer and aggregate was found to depend strongly upon detergent, temperature and nature of additives, such as ethylene glycol used for low temperature spectroscopy and polyethylene glycol used for crystallization. Likely aggregate structures are being identified by fitting the experimental scattering profiles with those calculated for model aggregates built-up using the RC crystal structure. This work establishes the foundation for using SANS to identify intermediates in the RC crystallization pathways, and for determining likely structures of complexes formed between the RC and its physiological reaction partners, cytochrome c, and the LHI antenna complex.

Tiede, D.M.; Marone, P.; Wagner, A.M.; Thiyagarajan, P.

1995-12-31T23:59:59.000Z

251

High-pressure Magic Angle Spinning Nuclear Magnetic Resonance  

Science Conference Proceedings (OSTI)

A high-pressure magic angle spinning (MAS) NMR capability, consisting of a reusable high-pressure MAS rotor, a high-pressure loading/reaction chamber for in situ sealing and re-opening of the high-pressure MAS rotor, and a MAS probe with a localized RF coil for background signal suppression, is reported. The unusual technical challenges associated with development of a reusable high-pressure MAS rotor are addressed in part by modifying standard ceramics for the rotor sleeve to include micro-groves at the internal surface at both ends of the cylinder. In this way, not only is the advantage of ceramic cylinders for withstanding very high-pressure utilized, but also plastic bushings can be glued tightly in place so that other plastic sealing mechanisms/components and O-rings can be mounted to create the desired high-pressure seal. Using this strategy, sealed internal pressures exceeding 150 bars have been achieved and sustained under ambient external pressure with minimal penetration loss of pressure for 72 hours. As an application example, in situ 13C MAS NMR studies of mineral carbonation reaction intermediates and final products of forsterite (Mg2SiO4) reacted with supercritical CO2 and H2O at 150 bar and 50?C are reported, with relevance to geological sequestration of carbon dioxide.

Hoyt, David W.; Turcu, Romulus VF; Sears, Jesse A.; Rosso, Kevin M.; Burton, Sarah D.; Felmy, Andrew R.; Hu, Jian Z.

2011-10-01T23:59:59.000Z

252

A NEW MEASUREMENT OF THE WEAK MIXING ANGLE  

DOE Green Energy (OSTI)

The E158 experiment at SLAC has made the first measurement of parity violation in electron-electron (Moeller) scattering. The authors report a preliminary result using 50% of the accumulated data sample for the right-left parity-violating cross-section asymmetry (A{sub PV}) in the elastic scattering of 45 and 48 GeV polarized electron beams with unpolarized electrons in a liquid hydrogen target. They find A{sub PV} = (-160 {+-} 21(stat.) {+-} 17(syst.)) {center_dot} 10{sup -9}, with a significance of 6.3{sigma} for observing parity violation. In the context of the Standard Model, this yields a measurement of the weak mixing angle, sin{sup 2} {theta}{sub W}{sup {ovr MS}} (Q{sup 2} = 0.026GeV{sup 2}) = 0.2379 {+-} 0.0016(stat.) {+-} 0.0013(syst.). They also present preliminary results for the first observation of a single-spin transverse asymmetry in Moeller scattering.

Woods, M

2004-02-26T23:59:59.000Z

253

Consistent Adjoint Driven Importance Sampling using Space, Energy and Angle  

Science Conference Proceedings (OSTI)

For challenging radiation transport problems, hybrid methods combine the accuracy of Monte Carlo methods with the global information present in deterministic methods. One of the most successful hybrid methods is CADIS Consistent Adjoint Driven Importance Sampling. This method uses a deterministic adjoint solution to construct a biased source distribution and consistent weight windows to optimize a specific tally in a Monte Carlo calculation. The method has been implemented into transport codes using just the spatial and energy information from the deterministic adjoint and has been used in many applications to compute tallies with much higher figures-of-merit than analog calculations. CADIS also outperforms user-supplied importance values, which usually take long periods of user time to develop. This work extends CADIS to develop weight windows that are a function of the position, energy, and direction of the Monte Carlo particle. Two types of consistent source biasing are presented: one method that biases the source in space and energy while preserving the original directional distribution and one method that biases the source in space, energy, and direction. Seven simple example problems are presented which compare the use of the standard space/energy CADIS with the new space/energy/angle treatments.

Peplow, Douglas E. [ORNL; Mosher, Scott W [ORNL; Evans, Thomas M [ORNL

2012-08-01T23:59:59.000Z

254

Cosmological lepton asymmetry with a nonzero mixing angle $\\theta_{13}$  

E-Print Network (OSTI)

While the baryon asymmetry of the Universe is nowadays well measured by cosmological observations, the bounds on the lepton asymmetry in the form of neutrinos are still significantly weaker. We place limits on the relic neutrino asymmetries using some of the latest cosmological data, taking into account the effect of flavor oscillations. We present our results for two different values of the neutrino mixing angle \\theta_{13}, and show that for large \\theta_{13} the limits on the total neutrino asymmetry become more stringent, diluting even large initial flavor asymmetries. In particular, we find that the present bounds are still dominated by the limits coming from Big Bang Nucleosynthesis, while the limits on the total neutrino mass from cosmological data are essentially independent of \\theta_{13}. Finally, we perform a forecast for COrE, taken as an example of a future CMB experiment, and find that it could improve the limits on the total lepton asymmetry approximately by up to a factor 5.

Castorina, Emanuele; Lattanzi, Massimiliano; Lesgourgues, Julien; Mangano, Gianpiero; Melchiorri, Alessandro; Pastor, Sergio

2012-01-01T23:59:59.000Z

255

Band gap enhancement of glancing angle deposited TiO{sub 2} nanowire array  

SciTech Connect

Vertically oriented TiO{sub 2} nanowire (NW) arrays were fabricated by glancing angle deposition technique. Field emission-scanning electron microscopy shows the formation of two different diameters {approx}80 nm and {approx}40 nm TiO{sub 2} NW for 120 and 460 rpm azimuthal rotation of the substrate. The x-ray diffraction and Raman scattering depicted the presence of rutile and anatase phase TiO{sub 2}. The overall Raman scattering intensity decreased with nanowire diameter. The role of phonon confinement in anatase and rutile peaks has been discussed. The red (7.9 cm{sup -1} of anatase E{sub g}) and blue (7.4 cm{sup -1} of rutile E{sub g}, 7.8 cm{sup -1} of rutile A{sub 1g}) shifts of Raman frequencies were observed. UV-vis absorption measurements show the main band absorption at 3.42 eV, 3.48 eV, and {approx}3.51 eV for thin film and NW prepared at 120 and 460 rpm, respectively. Three fold enhance photon absorption and intense light emission were observed for NW assembly. The photoluminescence emission from the NW assembly revealed blue shift in main band transition due to quantum confinement in NW structures.

Chinnamuthu, P.; Mondal, A.; Singh, N. K.; Dhar, J. C. [National Institute of Technology Agartala, Department of Electronics and Communication Engineering, Jirania, Tripura (West) 799055 (India); Chattopadhyay, K. K. [Jadavpur University, Department of Physics, Kolkata 700032 (India); Bhattacharya, Sekhar [SSN Research Centre, Tamil Nadu 603110 (India)

2012-09-01T23:59:59.000Z

256

The Impact of the Ice Phase and Radiation on a Midlatitude Squall Line System  

Science Conference Proceedings (OSTI)

A two-dimensional cloud model is used to study the interrelationships among cloud microphysics, radiation, and dynamics in a midlatitude broken-line squall system. The impact of the ice phase, longwave and shortwave radiation on the dynamic and ...

Hung-Neng S. Chin

1994-11-01T23:59:59.000Z

257

Radiation Dry Bias in the TWP-ICE Radiosonde Soundings Solar Zenith Angle Correction Factor  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation Dry Bias in the TWP-ICE Radiosonde Soundings Radiation Dry Bias in the TWP-ICE Radiosonde Soundings Solar Zenith Angle Correction Factor Figure 3: Ratio of MWR TCWV to radiosonde derived TCWV, and the solar zenith angle at the radiosonde launch time (black dots). The dry bias observed in sonde TCWV values is mainly attributable to a dry RH bias near the surface The red dots show the 1000 hPa RH correction factors suggested by Voemel et al for sondes launched near noon (10-30 degree solar zenith angle), and at night time (90 degree zenith angle). The green line shows a modified RH correction factor which is a function of the solar zenith angle. ● During the day-time, the TCWV bias is significantly smaller when the zenith angle correction is applied than when no correction, or only the Crad and Ccal corrections are applied.

258

Development of a hybrid margin angle controller for HVDC continuous operation  

SciTech Connect

The objective of this paper is to present a new hybrid margin angle control method for HVDC continuous operation under AC system fault conditions. For stable continuous operation of HVDC systems, the margin angle controller must be designed to maintain the necessary margin angle to avoid commutation failures. The proposed method uses the open loop margin angle controller (MAC) as the basic controller, and adds output from the closed loop MAC to correct the control angle. A fast voltage detection algorithm is used for open loop control, and margin angle reference correction using harmonics detection for closed loop control are also developed. The combination of open and closed loop control provides quick responses when faults occur with stable and speedy recovery after fault clearance. The effectiveness of the developed controller is confirmed through EMTP digital simulations and also with the experiments using an analogue simulator.

Sato, M. [Kansai Electric Power Co., Osaka (Japan); Yamaji, K. [Shikoku Electric Power Co., Takamatsu (Japan); Sekita, M. [Electric Power Development Co., Tokyo (Japan); Amano, M.; Nishimura, M.; Konishi, H.; Oomori, T. [Hitachi, Ltd. (Japan)

1996-11-01T23:59:59.000Z

259

Method and apparatus for controlling pitch and flap angles of a wind turbine  

DOE Patents (OSTI)

A wind turbine with improved response to wind conditions is provided. Blade flap angle motion is accompanied by a change in pitch angle by an amount defining a pitch/flap coupling ratio. The coupling ratio is non-constant as a function of a flap angle and is preferably a substantially continuous, non-linear function of flap angle. The non-constant coupling ratio can be provided by mechanical systems such as a series of linkages or by configuring electronic or other control systems and/or angle sensors. A link with a movable proximal end advantageously is part of the mechanical system. The system can provide relatively large coupling ratios and relatively large rates of coupling ratio changes especially for near-feather pitches and low flap angles.

Deering, Kenneth J. (Seattle, WA); Wohlwend, Keith P. (Issaquah, WA)

2009-05-12T23:59:59.000Z

260

Simulations of astronomical imaging phased arrays  

E-Print Network (OSTI)

We describe a theoretical procedure for analyzing astronomical phased arrays with overlapping beams, and apply the procedure to simulate a simple example. We demonstrate the effect of overlapping beams on the number of degrees of freedom of the array, and on the ability of the array to recover a source. We show that the best images are obtained using overlapping beams, contrary to common practise, and show how the dynamic range of a phased array directly affects the image quality.

George Saklatvala; Stafford Withington; Michael P. Hobson

2007-09-04T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

NA Standards | Valence Geometries | Bond Lengths & Angles - Thymine  

NLE Websites -- All DOE Office Websites (Extended Search)

Thymine Thymine ---------------------------------------------------- Bond or Angle Mean (esd, N) Value ---------------------------------------------------- N1-C2 1.376 (0.008, 50) C2-N3 1.373 (0.008, 50) N3-C4 1.382 (0.008, 50) C4-C5 1.445 (0.009, 50) C5-C6 1.339 (0.007, 50) C6-N1 1.378 (0.007, 50) C2-O2 1.220 (0.008, 50) C4-O4 1.228 (0.009, 50) C5-M5 1.496 (0.006, 50) N1-C1' 1.473 (0.014, 50) C6-N1-C2 121.3 (0.5, 50) N1-C2-N3 114.6 (0.6, 50) C2-N3-C4 127.2 (0.6, 50) N3-C4-C5 115.2 (0.6, 50) C4-C5-C6 118.0 (0.6, 50) C5-C6-N1 123.7 (0.6, 50) N1-C2-O2 123.1 (0.8, 50) N3-C2-O2 122.3 (0.6, 50) N3-C4-O4 119.9 (0.6, 50) C5-C4-O4 124.9 (0.7, 50) C4-C5-M5 119.0 (0.6, 50)

262

NA Standards | Valence Geometries | Bond Lengths & Angles - Protonated  

NLE Websites -- All DOE Office Websites (Extended Search)

Protonated Cytosine Protonated Cytosine ---------------------------------------------------- Bond or Angle Mean (esd, N) Value ---------------------------------------------------- N1-C2 1.381 (0.007, 17) C2-N3 1.384 (0.007, 17) N3-C4 1.353 (0.006, 17) C4-C5 1.413 (0.005, 17) C5-C6 1.346 (0.006, 17) C6-N1 1.365 (0.007, 17) C2-O2 1.212 (0.006, 17) C4-N4 1.315 (0.007, 17) N1-C1' 1.483 (0.015, 17) C6-N1-C2 121.7 (0.5, 17) N1-C2-N3 114.7 (0.7, 17) C2-N3-C4 125.3 (0.7, 17) N3-C4-C5 117.6 (0.5, 17) C4-C5-C6 118.4 (0.5, 17) C5-C6-N1 122.2 (0.5, 17) N1-C2-O2 123.4 (0.7, 17) N3-C2-O2 121.9 (0.5, 17) N3-C4-N4 119.5 (0.7, 17) C5-C4-N4 123.0 (0.8, 17) C6-N1-C1' 121.2 (0.9, 17) C2-N1-C1' 116.9 (1.0, 17

263

NA Standards | Valence Geometries | Bond Lengths & Angles - Uracil  

NLE Websites -- All DOE Office Websites (Extended Search)

Uracil Uracil ---------------------------------------------------- Bond or Angle Mean (esd, N) Value ---------------------------------------------------- N1-C2 1.381 (0.009, 46) C2-N3 1.373 (0.007, 46) N3-C4 1.380 (0.009, 46) C4-C5 1.431 (0.009, 46) C5-C6 1.337 (0.009, 46) C6-N1 1.375 (0.009, 46) C2-O2 1.219 (0.009, 46) C4-O4 1.232 (0.008, 46) N1-C1' 1.469 (0.014, 46) C6-N1-C2 121.0 (0.6, 46) N1-C2-N3 114.9 (0.6, 46) C2-N3-C4 127.0 (0.6, 46) N3-C4-C5 114.6 (0.6, 46) C4-C5-C6 119.7 (0.6, 46) C5-C6-N1 122.7 (0.5, 46) N1-C2-O2 122.8 (0.7, 46) N3-C2-O2 122.2 (0.7, 46) N3-C4-O4 119.4 (0.7, 46) C5-C4-O4 125.9 (0.6, 46) C6-N1-C1' 121.2 (1.4, 46) C2-N1-C1' 117.7 (1.2, 46

264

Dynamic tariffs  

SciTech Connect

The general theoretical models of dynamic tariffs, such as spot pricing, are extended in this paper to include the issues of optimal response of industrial consumers and the effect of large scale penetration of these tariffs on the utility load curve. If such tariffs are to serve their purpose consumers need to acquire the ability for flexible and dynamic response. While the hardware for this is readily available the theoretical models and software systems are not. These issues are examined and correlated with industrial site studies. A systematic analysis of the effect of significant consumer response on the system load curve is next undertaken. A methodologically sound approach to system load and price forecasting is presented.

David, A.K.; Lee, Y.C.

1989-08-01T23:59:59.000Z

265

MATHEMATICAL MODELS OF HYSTERESIS (DYNAMIC PROBLEMS IN HYSTERESIS)  

SciTech Connect

This research has further advanced the current state of the art in the areas of dynamic aspects of hysteresis and nonlinear large scale magnetization dynamics. The results of this research will find important engineering applications in the areas of magnetic data storage technology and the emerging technology of spintronics. Our research efforts have been focused on the following tasks: Study of fast (pulse) precessional switching of magnetization in magnetic materials. Analysis of critical fields and critical angles for precessional switching of magnetization. Development of inverse problem approach to the design of magnetic field pulses for precessional switching of magnetization. Study of magnetization dynamics induced by spin polarized current injection. Construction of complete stability diagrams for spin polarized current induced magnetization dynamics. Development of the averaging technique for the analysis of the slow time scale magnetization dynamics. Study of thermal effects on magnetization dynamics by using the theory of stochastic processes on graphs.

Professor Isaak Mayergoyz

2006-08-21T23:59:59.000Z

266

Anomalous Small-angle Scattering with Soft X-rays at Al and Si K ...  

Science Conference Proceedings (OSTI)

Anomalous Small-angle Scattering with Soft X-rays at Al and Si K Absorption ... and Cooling Cycles in a High Strength Quenched and Tempered Structural Steel.

267

Causal signal transmission by quantum fields. VI: Phase-space approach to quantum electrodynamics  

E-Print Network (OSTI)

Phase-space techniques are generalized to nonlinear quantum electrodynamics beyond the rotating wave approximation, resulting in an essentially classical picture of radiation dynamics.

L. I. Plimak; S. T. Stenholm

2011-04-19T23:59:59.000Z

268

A Phase-Field Model for Phase Transformations in Glass-Forming Alloys  

SciTech Connect

A phase-field model is proposed for phase transformations in glass-forming alloys. The glass transition is introduced as a structural relaxation, and the competition between the glass and crystalline phases is investigated. The simulations are performed for Cu-Zr alloys, employing thermodynamic and kinetic parameters derived from reported thermodynamic modeling and molecular dynamics simulation results,[13] respectively. Four distinct phase fields are treated with a multi-phase-field approach, representing the liquid/glass, Cu10Zr7, CuZr, and CuZr2 phases. In addition, a continuum-field method is applied to the liquid to accommodate the liquidglass transformation. The combined phase-field approach is used to investigate the glass formation tendency, and critical cooling rates are estimated and compared with the reported experimental values.

Wang, Tao; Napolitano, Ralph E.

2012-03-24T23:59:59.000Z

269

Economic Recovery of Oil Trapped at Fan Margins Using Hig Angle Wells Multiple Hydraulic Fractures  

Science Conference Proceedings (OSTI)

The Yowlumne field is a giant field in the southern San Joaquin basin, Kern County, California. It is a deep (13,000 ft) waterflood operation that produces from the Miocene- aged Stevens Sand. The reservoir is interpreted as a layered, fan-shaped, prograding turbidite complex containing several lobe-shaped sand bodies that represent distinct flow units. A high ultimate recovery factor is expected, yet significant quantities of undrained oil remain at the fan margins. The fan margins are not economic to develop using vertical wells because of thinning pay, deteriorating rock quality, and depth. This project attempts to demonstrate the effectiveness of exploiting the northeast distal fan margin through the use of a high- angle well completed with multiple hydraulic- fracture treatments. A high-angle well offers greater pay exposure than can be achieved with a vertical well. Hydraulic-fracture treatments will establish vertical communication between thin interbedded layers and the wellbore. The equivalent production rate and reserves of three vertical wells are anticipated at a cost of approximately two vertical wells. The near-horizontal well penetrated the Yowlumne sand; a Stevens sand equivalent, in the distal fan margin in the northeast area of the field. The well was drilled in a predominately westerly direction towards the interior of the field, in the direction of improving rock quality. Drilling and completion operations proved to be very challenging, leading to a number of adjustments to original plans. Hole conditions resulted in obtaining less core material than desired and setting intermediate casing 1200 ft too high. The 7 in. production liner stuck 1000 ft off bottom, requiring a 5 in. liner to be run the rest of the way. The cement job on the 5 in. liner resulted in a very poor bond, which precluded one of three hydraulic fracture treatments originally planned for the well. Openhole logs confirmed most expectations going into the project about basic rock properties: the formation was shaly with low porosities, and water saturations were in line with expectations, including the presence of some intervals swept out by the waterflood. High water saturations at the bottom of the well eliminated one of the originally planned hydraulic fracture treatments. Although porosities proved to be low, they were more uniform across the formation than expected. Permeabilities of the various intervals continue to be evaluated, but appear to be better than expected from the porosity log model derived in Budget Period One. The well was perforated in all pay sections behind the 5 in. liner. Production rates and phases agree nicely with log calculations, fractional flow calculations, and an analytical technique used to predict the rate performance of the well.

Laue, M.L.

1997-11-21T23:59:59.000Z

270

ARM: Shortwave Array Spectroradiometer-Hemispheric, VISible channel, low-sun angles [a0 data is uncalibrated  

DOE Data Explorer (OSTI)

Shortwave Array Spectroradiometer-Hemispheric, VISible channel, low-sun angles [a0 data is uncalibrated

Connor Flynn

271

ARM: Shortwave Array Spectroradiometer-Hemispheric, VISible channel, high-sun angles [a0 data is uncalibrated  

DOE Data Explorer (OSTI)

Shortwave Array Spectroradiometer-Hemispheric, VISible channel, high-sun angles [a0 data is uncalibrated

Connor Flynn

272

ARM: Shortwave Array Spectroradiometer-Hemispheric, VISible channel, low-sun angles [a0 data is uncalibrated  

SciTech Connect

Shortwave Array Spectroradiometer-Hemispheric, VISible channel, low-sun angles [a0 data is uncalibrated

Connor Flynn

2011-03-22T23:59:59.000Z

273

ARM: Shortwave Array Spectroradiometer-Hemispheric, VISible channel, high-sun angles [a0 data is uncalibrated  

SciTech Connect

Shortwave Array Spectroradiometer-Hemispheric, VISible channel, high-sun angles [a0 data is uncalibrated

Connor Flynn

2011-03-22T23:59:59.000Z

274

Glass Transition by Gelation in a Phase Separating Binary Alloy  

E-Print Network (OSTI)

We use molecular dynamics simulations to show that glass transition in a model phase separating amorphous alloy, Cu50Nb50, occurs by gelation. At the glass transition, a mechanically stiff, percolating network of atoms ...

Baumer, Richard E.

275

Gas phase 129Xe NMR imaging and spectroscopy  

E-Print Network (OSTI)

5 l l Dynamic NMR microscopy of gas phase Poiseuille flowmetal vapors and noble gases can be used to efficientlypolarize the nuclei ofthe noble-gas atoms. As a result, the

Kaiser, Lana G.

2010-01-01T23:59:59.000Z

276

Autumnal Mixed-Phase Cloudy Boundary Layers in the Arctic  

Science Conference Proceedings (OSTI)

Two mixed-phase cloudy boundary layer events observed over the Arctic ice pack in autumn are extensively analyzed. The local dynamic and thermodynamic structure of the boundary layers is determined from aircraft measurements including analysis of ...

James O. Pinto

1998-06-01T23:59:59.000Z

277

Comparison of Aircraft Observations with Mixed-Phase Cloud Simulations  

Science Conference Proceedings (OSTI)

In order to provide guidance for the further improvement of a mixed-phase cloud scheme being developed for use in an NWP model, comparisons of dynamical, thermodynamical, and microphysical variables between in situ aircraft data and model data ...

Paul A. Vaillancourt; Andr Tremblay; Stewart G. Cober; George A. Isaac

2003-04-01T23:59:59.000Z

278

Temperature-insensitive phase-matched optical harmonic conversion crystal  

DOE Patents (OSTI)

Temperature-insensitive, phase-matched harmomic frequency conversion of laser light at a preferred wavelength of 1.064 microns can be achieved by use of a crystal of deuterated l-arginine phosphate. The crystal is cut and oriented so that the laser light propagates inside the crystal along one of several required directions, which correspond to a temperature-insensitive, phase-matching locus. The method of measuring and calculating the temperature-insensitive, phase-matching angles can be extended to other fundamental wavelengths and other crystal compositions.

Barker, Charles E. (Sunnyvale, CA); Eimerl, David (Livermore, CA); Velsko, Stephan P. (Livermore, CA); Roberts, David (Sagamore Hills, OH)

1993-01-01T23:59:59.000Z

279

Ab-Initio Molecular Dynamics  

E-Print Network (OSTI)

Computer simulations and molecular dynamics in particular, is a very powerful method to provide detailed and essentially exact informations of classical many-body problems. With the advent of \\textit{ab-initio} molecular dynamics, where the forces are computed on-the-fly by accurate electronic structure calculations, the scope of either method has been greatly extended. This new approach, which unifies Newton's and Schr\\"odinger's equations, allows for complex simulations without relying on any adjustable parameter. This review is intended to outline the basic principles as well as a survey of the field. Beginning with the derivation of Born-Oppenheimer molecular dynamics, the Car-Parrinello method as well as novel hybrid scheme that unifies best of either approach are discussed. The predictive power is demonstrated by a series of applications ranging from insulators to semiconductors and even metals in condensed phases.

Khne, Thomas D

2012-01-01T23:59:59.000Z

280

Phase I ResonantSonic CRADA report  

Science Conference Proceedings (OSTI)

This test report describes the Phase 1 testing and results of the ResonantSonic drilling method. This effort was conducted as part of a Cooperative Research and Development Agreement (CRADA) between the US Department of Energy, Pacific Northwest Laboratory, Westinghouse Hanford Company and Water Development Corporation. The purpose of this demonstration was to evaluate the Water Development Corporation`s ResonantSonic drilling system, modify components as necessary and determine compatible drilling applications for the ResonantSonic drilling method for use at facilities in the DOE complex and private industry. Initially, the ResonantSonic drill was used to drill several test holes at the Drilling Technology Test Site to assess the feasibility of drilling vertical and angle holes. After this initial phase, a 45 degree angle vapor extraction well was drilled to a depth of 168 feet at the 200 West Carbon Tetrachloride Site. This well was drilled and completed in nine days. Extensive geologic and vapor sampling were conducted while drilling this well. In addition, testing was also conducted at the test site to evaluated drilling with larger diameter casing (8 5/8 inch). Evaluation of the Resonant Sonic drilling method will be continued during the Phase 2 portion of testing to determine if improvements to the ResonantSonic system will make it a more viable method for drilling and sampling.

Richterich, L.R.; Amos, L.O.; Fancher, J.D.; McLellan, G.W.; Setzer, W.V.; Tuttle, B.G. [Westinghouse Hanford Co., Richland, WA (United States); Hockey, R.L.; Ferris, R.H.; Riechers, D.M.; Pitman, S.G. [Pacific Northwest Lab., Richland, WA (United States)

1994-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Dielectric energy versus plasma energy, and Hamiltonian action-angle variables for the Vlasov equation  

Science Conference Proceedings (OSTI)

Expressions for the energy content of one-dimensional electrostatic perturbations about homogeneous equilibria are revisited. The well-known dielectric energy, {var epsilon}{sub D}, is compared with the exact plasma free energy expression, {delta}{sup 2}F, that is conserved by the Vlasov-Poisson system. The former is an expression in terms of the perturbed electric field amplitude, while the latter is determined by a generating function, which describes perturbations of the distribution function that respect the important constraint of dynamical accessibility of the system. Thus the comparison requires solving the Vlasov equation for such a perturbations of the distribution function in terms of the electric field. This is done for neutral modes of oscillation that occur for equilibria with stationary inflection points, and it is seen that for these special modes {delta}{sup 2}F = {var epsilon}{sub D}. In the case of unstable and corresponding damped modes it is seen that {delta}{sup 2}F {ne} {var epsilon}{sub D}; in fact {delta}{sup 2}F {equivalent to} 0. This failure of the dielectric energy expression persists even for arbitrarily small growth and damping rates since {var epsilon}{sub D} is nonzero in this limit, whereas {delta}{sup 2}F remains zero. The connection between the new exact energy expression and the at-best approximate {var epsilon}{sub D} is described. The new expression motivates natural definitions of Hamiltonian action variables and signature. A general linear integral transform is introduced that maps the linear version of the noncanonical Hamiltonian structure, which describes the Vlasov equation, to action-angle (diagonal) form.

Morrison, P.J. (Texas Univ., Austin, TX (United States). Inst. for Fusion Studies); Pfirsch, D. (Max-Planck-Institut fuer Plasmaphysik, Garching (Germany))

1992-04-01T23:59:59.000Z

282

Dielectric energy versus plasma energy, and Hamiltonian action-angle variables for the Vlasov equation  

Science Conference Proceedings (OSTI)

Expressions for the energy content of one-dimensional electrostatic perturbations about homogeneous equilibria are revisited. The well-known dielectric energy, {var_epsilon}{sub D}, is compared with the exact plasma free energy expression, {delta}{sup 2}F, that is conserved by the Vlasov-Poisson system. The former is an expression in terms of the perturbed electric field amplitude, while the latter is determined by a generating function, which describes perturbations of the distribution function that respect the important constraint of dynamical accessibility of the system. Thus the comparison requires solving the Vlasov equation for such a perturbations of the distribution function in terms of the electric field. This is done for neutral modes of oscillation that occur for equilibria with stationary inflection points, and it is seen that for these special modes {delta}{sup 2}F = {var_epsilon}{sub D}. In the case of unstable and corresponding damped modes it is seen that {delta}{sup 2}F {ne} {var_epsilon}{sub D}; in fact {delta}{sup 2}F {equivalent_to} 0. This failure of the dielectric energy expression persists even for arbitrarily small growth and damping rates since {var_epsilon}{sub D} is nonzero in this limit, whereas {delta}{sup 2}F remains zero. The connection between the new exact energy expression and the at-best approximate {var_epsilon}{sub D} is described. The new expression motivates natural definitions of Hamiltonian action variables and signature. A general linear integral transform is introduced that maps the linear version of the noncanonical Hamiltonian structure, which describes the Vlasov equation, to action-angle (diagonal) form.

Morrison, P.J. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies; Pfirsch, D. [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

1992-04-01T23:59:59.000Z

283

Calculation and Analysis of Optimal Tilt Angle for PV/T Hybrid Collector  

Science Conference Proceedings (OSTI)

The use of solar energy received world wide attention in recent years. Solar energy is a free and clean natural resource which can be utilized by using a solar collector. In this paper, a model was presented for the calculation of the optimal tilt angle ... Keywords: Solar energy, Optimal tilt angle, Optimization, PV/T hybrid collector

Xianping Liu

2012-01-01T23:59:59.000Z

284

Mobility of organic pollutants in soil components. What role can magic angle spinning NMR play?  

E-Print Network (OSTI)

Mobility of organic pollutants in soil components. What role can magic angle spinning NMR play? C resonance (NMR) spectroscopy on dry samples. We recently demonstrated the potential of the 1 H high resolution magic angle spinning (MAS) NMR technique to study such mechanisms in situ on highly hydrated

Paris-Sud XI, Université de

285

Parity Violation in elastic electron scattering : A first measurment of the parity-violating Asymmetry at Q2 = 0.631 GeV/c2 at Backward Angle.  

DOE Green Energy (OSTI)

The goal of Experiment E04-115 (the G0 backward angle measurement) at Jefferson Lab is to investigate the contributions of strange quarks to the fundamental properties of the nucleon. The experiment measures parity-violating asymmetries in elastic electron scattering off hydrogen and quasielastic electron scattering off deuterium at backward angles at Q2 = 0.631 (GeV/c)2 and Q2 = 0.232 (GeV/c)2. The backward angle measurement represents the second phase of the G0 experiment. The first phase, Experiment E00-006 (the G0 forward angle experiment), measured parity-violating asymmetries in elastic electron scattering off hydrogen at forward angles over a Q2 range of 0.1-1.0 (GeV/c)2. The experiments used a polarized electron beam and unpolarized hydrogen and deuterium liquid targets. From these measurements, along with the electromagnetic form factors, one can extract the contribution of the strange quark to the proton's charge and magnetization distributions. This thesis represents a fi

Bailey, Stephanie

2007-05-01T23:59:59.000Z

286

An acceleration of the characteristics by a space-angle two-level method using surface discontinuity factors  

Science Conference Proceedings (OSTI)

We present a non-linear space-angle two-level acceleration scheme for the method of the characteristics (MOC). To the fine level on which the MOC transport calculation is performed, we associate a more coarsely discretized phase space in which a low-order problem is solved as an acceleration step. Cross sections on the coarse level are obtained by a flux-volume homogenisation technique, which entails the non-linearity of the acceleration. Discontinuity factors per surface are introduced as additional degrees of freedom on the coarse level in order to ensure the equivalence of the heterogeneous and the homogenised problem. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenised grid. The solution of this problem is then used to correct the angular moments of the flux resulting from the previous free transport sweep. Numerical tests for a given benchmark have been performed. Results are discussed. (authors)

Grassi, G. [Commissariat a l'Energie Atomique, CEA de Saclay, DM2S/SERMA/LENR, 91191, Gif-sur-Yvette (France)

2006-07-01T23:59:59.000Z

287

Pitch Angle Control of Variable Low Rated Speed Wind Turbine Using Fuzzy Logic Control  

E-Print Network (OSTI)

Abstract Pitch angle control of wind turbine has been used widely to reduce torque and output power variation in high rated wind speed areas. It is a challenge to maximize available energy in the low rated wind speed areas. In this paper, a wind turbine prototype with a pitch angle control based on fuzzy logic to maximize the output power is built and demonstrated. In the varying low rated wind speed of 4-6 m/s, the use of fuzzy logic controller can maximize the average output power of 14.5 watt compared to 14.0 watt at a fixed pitch angle of the blade. Implementation of pitch angle fuzzy logic-based control to the wind turbine is suitable for the low rated wind speed areas. Index Terms low rated wind speed areas, pitch angle control, fuzzy logic, wind turbine. T I.

A. Musyafa; A. Harika; I. M. Y. Negara; I. Rob

2010-01-01T23:59:59.000Z

288

Bonding in the Superionic Phase of Water  

DOE Green Energy (OSTI)

The predicted superionic phase of water is investigated via ab initio molecular dynamics at densities of 2.0-3.0 g/cc (34-115 GPa) along the 2000K isotherm. They find that extremely rapid (superionic) diffusion of protons occurs in a fluid phase at pressures between 34 and 58 GPa. A transition to a stable body-centered cubic (bcc) O lattice with superionic proton conductivity is observed between 70 and 75 GPa, a much higher pressure than suggested in prior work. They find that all molecular species at pressures greater than 75 GPa are too short lived to be classified as bound states. Up to 95 GPa, they find a solid superionic phase characterization by covalent O-H bonding. Above 95 GPa, a transient network phase is found characterized by symmetric O-H hydrogen bonding with nearly 50% covalent character. In addition, they describe a new metastable superionic phase with quenched O disorder.

Goldman, N; Fried, L E; Kuo, I W; Mundy, C J

2005-02-07T23:59:59.000Z

289

Measurement of the Weak Mixing Angle in Moller Scattering  

DOE Green Energy (OSTI)

The weak mixing parameter, sin{sup 2} {theta}{sub w}, is one of the fundamental parameters of the Standard Model. Its tree-level value has been measured with high precision at energies near the Z{sup 0} pole; however, due to radiative corrections at the one-loop level, the value of sin{sup 2} {theta}{sub w} is expected to change with the interaction energy. As a result, a measurement of sin{sup 2} {theta}{sub w} at low energy (Q{sup 2} << m{sub Z}, where Q{sup 2} is the momentum transfer and m{sub Z} is the Z boson mass), provides a test of the Standard Model at the one-loop level, and a probe for new physics beyond the Standard Model. One way of obtaining sin{sup 2} {theta}{sub w} at low energy is from measuring the left-right, parity-violating asymmetry in electron-electron (Moeller) scattering: A{sub PV} = {sigma}{sub R}-{sigma}{sub L}/{sigma}{sub R}+{sigma}{sub L}, where {sigma}{sub R} and {sigma}{sub L} are the cross sections for right- and left-handed incident electrons, respectively. The parity violating asymmetry is proportional to the pseudo-scalar weak neutral current coupling in Moeller scattering, g{sub ee}. At tree level g{sub ee} = (1/4 -sin{sup 2} {theta}{sub w}). A precision measurement of the parity-violating asymmetry in Moeller scattering was performed by Experiment E158 at the Stanford Linear Accelerator Center (SLAC). During the experiment, {approx}50 GeV longitudinally polarized electrons scattered off unpolarized atomic electrons in a liquid hydrogen target, corresponding to an average momentum transfer Q{sup 2} {approx} 0.03 (GeV/c){sup 2}. The tree-level prediction for A{sub PV} at such energy is {approx}300 ppb. However one-loop radiative corrections reduce its value by {approx}40%. This document reports the E158 results from the 2002 data collection period. The parity-violating asymmetry was found to be A{sub PV} = -160 {+-} 21 (stat.) {+-} 17 (syst.) ppb, which represents the first observation of a parity-violating asymmetry in Moeller scattering. This value corresponds to a weak mixing angle at Q{sup 2} = 0.026 (GeV/c){sup 2} of sin{sup 2} {theta}{sub w{ovr MS}} = 0.2379 {+-} 0.0016 (stat.) {+-} 0.0013 (syst.), which is -0.3 standard deviations away from the Standard Model prediction: sin{sup 2} {theta}{sub w{ovr MS}}{sup predicted} = 0.2385 {+-} 0.0006 (theory). The E158 measurement of sin{sup 2} {theta}{sub w} at a precision of {delta}(sin{sup 2} {theta}{sub w}) = 0.0020 provides new physics sensitivity at the TeV scale.

Klejda, B.

2005-01-28T23:59:59.000Z

290

Dynamical failure of Turing patterns  

E-Print Network (OSTI)

The emergence of stable disordered patterns in reactive system on spatially homogenous substrate is studied in the context of vegetation patterns in the semi-arid climatic zone. It is shown that reaction-diffusion systems that allow for Turing instability may exhibit heterogeneous "glassy" steady state, with no characteristic wavelength, if the diffusion rate associated with the "slow" reactant is very small. Upon decreasing the diffusion constant of the slow reactant three phases are identified: strong diffusion yields a stable homogenous phase, intermediate diffusion implies Turing (crystal like) patterns while in the slow diffusion limit the glassy state is the generic stable solution. In this disordered phase the dynamics is of crucial importance, with strong differences between local and global initiation.

Alon Manor; Nadav M. Shnerb

2005-08-08T23:59:59.000Z

291

Metastable Phase Transformations  

Science Conference Proceedings (OSTI)

Oct 8, 2012 ... The omega phase is commonly observed in many commercial beta or near-beta titanium alloys on quenching from single beta phase field.

292

Contact angle hysteresis of cylindrical drops on chemically heterogeneous striped surfaces  

E-Print Network (OSTI)

Contact angle hysteresis of a macroscopic droplet on a heterogeneous but flat substrate is studied using the interface displacement model. First, the apparent contact angle of a droplet on a heterogeneous surface under the condition of constant volume is considered. By assuming a cylindrical liquid-vapor surface (meniscus) and minimizing the total free energy, we derive an equation for the apparent contact angle, which is similar but different from the well-known Cassie's law. Next, using this modified Cassie's law as a guide to predict the behavior of a droplet on a heterogeneous striped surface, we examine several scenarios of contact angle hysteresis using a periodically striped surface model. By changing the volume of the droplet, we predict a sudden jump of the droplet edge, and a continuous change of the apparent contact angle at the edge of two stripes. Our results suggest that as drop volume is increased (advancing contact lines), the predominant drop configuration observed is the one whose contact angle is large; whereas, decreasing drop volume from a large value (receding contact lines) yields drop configuration that predominantly exhibit the smaller contact angle.

Masao Iwamatsu

2005-11-26T23:59:59.000Z

293

Phase Contrast Microscopy with Soft and Hard X-rays  

E-Print Network (OSTI)

Calibration ­ Uses up part of dynamic range · Solution: ­ Soft x-rays: Back side Illumination ­ Hard xPhase Contrast Microscopy with Soft and Hard X-rays Using a Segmented Detector Benjamin Hornberger ­ Phase Contrast 101 · A Segmented Detector for Hard X-ray Microprobes ­ Segmented Silicon Chip ­ Charge

Homes, Christopher C.

294

Prediction of Tropical Rainfall by Local Phase Space Reconstruction  

Science Conference Proceedings (OSTI)

The authors propose a weather prediction model based on a local reconstruction of the dynamics in phase space, using an 11-year dataset from Tlaxcala, Mexico. A vector in phase space corresponds to T consecutive days of data; the best predictions ...

H. Waelbroeck; R. Lpez-Pen?a; T. Morales; F. Zertuche

1994-11-01T23:59:59.000Z

295

Regional Dynamics Model (REDYN) | Open Energy Information  

Open Energy Info (EERE)

Regional Dynamics Model (REDYN) Regional Dynamics Model (REDYN) Jump to: navigation, search Tool Summary Name: REDYN Agency/Company /Organization: Regional Dynamics Inc. Sector: Energy Phase: Determine Baseline, "Evaluate Options and Determine Feasibility" is not in the list of possible values (Bring the Right People Together, Create a Vision, Determine Baseline, Evaluate Options, Develop Goals, Prepare a Plan, Get Feedback, Develop Finance and Implement Projects, Create Early Successes, Evaluate Effectiveness and Revise as Needed) for this property., Develop Goals Topics: Market analysis, Policies/deployment programs, Co-benefits assessment, - Macroeconomic Resource Type: Software/modeling tools User Interface: Desktop Application Website: www.regionaldynamics.com/

296

Amyloid fibril structure of peptides and proteins by magic angle spinning NMR spectroscopy and dynamic nuclear polarization  

E-Print Network (OSTI)

Amyloid fibrils are insoluble, non-crystalline protein filaments associated with a number of diseases such as Alzheimer's and Type Il diabetes. They can have a functional role in different organisms and many proteins and ...

Debelouchina, Galia Tzvetanova

2011-01-01T23:59:59.000Z

297

Role of the target orientation angle and orbital angular momentum in the evaporation residue production  

E-Print Network (OSTI)

The influence of the orientation angles of the target nucleus symmetry axis relative to the beam direction on the production of the evaporation residues is investigated for the $^{48}$Ca+$^{154}$Sm reaction as a function of the beam energy. At low energies ($E_{\\rm c.m.}orientation angles ($\\alpha_Torientation angles $\\alpha_T$ can contribute to the evaporation residue cross section $\\sigma_{ER}$ in the 10--100 mb range, and at $E_{c.m.}>$180 MeV $\\sigma_{ER}$ ranges around 0.1--10 mb because the fission barrier for a compound nucleus decreases by increasing its excitation energy and angular momentum.

Giovanni Fazio; Giorgio Giardina; Francis Hanappe; Giuseppe Mandaglio; Marina Manganaro; Akhtam I. Muminov; Avazbek K. Nasirov; Carmelo Sacca

2008-09-22T23:59:59.000Z

298

Analysis of the incidence angle of the beam radiation on CPC. [Compound Parabolic Concentrator  

SciTech Connect

Analytic expressions have been derived for the projected incidence angles {var theta}{sub 1} and {var theta}{sub 2} from a two-dimensional compound parabolic concentrator solar collector. For a CPC the fraction of the incident rays on the aperture at angle {var theta}, which reaches the absorber, depends only on the {var theta}{sub 1} angle. In this paper, a mathematical expression for {var theta}{sub 1} and {var theta}{sub t} has been calculated to determine the times at which acceptance of the sun's beam radiation begins and ceases for a CPC consisting of arbitrary orientation.

Pinazo, J.M.; Canada, J.; Arago, F. (Univ. Politecnica de Valencia (Spain))

1992-09-01T23:59:59.000Z

299

Morphological Phase Behavior of Poly(RTIL)-Containing Diblock Copolymer Melts  

Science Conference Proceedings (OSTI)

The development of nanostructured polymeric systems containing directionally continuous poly(ionic liquid) (poly(IL)) domains has considerable implications toward a range of transport-dependent, energy-based technology applications. The controlled, synthetic integration of poly(IL)s into block copolymer (BCP) architectures provides a promising means to this end, based on their inherent ability to self-assemble into a range of defined, periodic morphologies. In this work, we report the melt-state phase behavior of an imidazolium-containing alkyl-ionic BCP system, derived from the sequential ring-opening metathesis polymerization (ROMP) of imidazolium- and alkyl-substituted norbornene monomer derivatives. A series of 16 BCP samples were synthesized, varying both the relative volume fraction of the poly(norbornene dodecyl ester) block (f{sub DOD} = 0.42-0.96) and the overall molecular weights of the block copolymers (M{sub n} values from 5000-20,100 g mol{sup -1}). Through a combination of small-angle X-ray scattering (SAXS) and dynamic rheology, we were able to delineate clear compositional phase boundaries for each of the classic BCP phases, including lamellae (Lam), hexagonally packed cylinders (Hex), and spheres on a body-centered-cubic lattice (S{sub BCC}). Additionally, a liquid-like packing (LLP) of spheres was found for samples located in the extreme asymmetric region of the phase diagram, and a persistent coexistence of Lam and Hex domains was found in lieu of the bicontinuous cubic gyroid phase for samples located at the intersection of Hex and Lam regions. Thermal disordering was opposed even in very low molecular weight samples, detected only when the composition was highly asymmetric (f{sub DOD} = 0.96). Annealing experiments on samples exhibiting Lam and Hex coexistence revealed the presence of extremely slow transition kinetics, ultimately selective for one or the other but not the more complex gyroid phase. In fact, no evidence of the bicontinuous network was detected over a 2 month annealing period. The ramifications of these results for transport-dependent applications targeting the use of highly segregated poly(IL)-containing BCP systems are carefully considered.

Scalfani, Vincent F.; Wiesenauer, Erin F.; Ekblad, John R.; Edwards, Julian P.; Gin, Douglas L.; Bailey, Travis S. (CSU); (Colorado)

2012-10-23T23:59:59.000Z

300

Thermodynamics and Phase Diagrams  

Science Conference Proceedings (OSTI)

...Alloy Phase Diagrams and Microstructure, Metals Handbook Desk Edition, ASM International, 1998, p. 95??114...

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Dynamic interaction between tectonic plates, subducting slabs, and the mantle  

Science Conference Proceedings (OSTI)

Mantle convection models have been formulated to investigate the relation between plate kinematics and mantle dynamics. The cylindrical geometry models incorporate mobile, faulted plate margins, a phase change at 670 km depth, non-Newtonian ...

Shijie Zhong; Michael Gurnis

1997-01-01T23:59:59.000Z

302

Observed Dynamic Structure of an Intense Oceanic Cyclone  

Science Conference Proceedings (OSTI)

A major extratropical cyclone developed over the East China Sea during the initial phase of the AMTEX'75. Using cross-section analyses the dynamic structure of the cyclone is investigated with an emphasis on obtaining a better understanding of ...

C-B. Chang; D. J. Perkey; W-D. Chen

1987-06-01T23:59:59.000Z

303

Chaff Seeding Effects in a Dynamical-Electrical Cloud Model  

Science Conference Proceedings (OSTI)

A two-dimensional, slab-symmetric, time-dependent cloud model has been devised to simulate deep convection in the atmosphere. The dynamics and thermodynamics of deep convection are prescribed and the microphysics of the liquid phase is ...

John H. Helsdon Jr.

1980-09-01T23:59:59.000Z

304

Dependence of Land Surface Albedo on Solar Zenith Angle: Observations and Model Parameterization  

Science Conference Proceedings (OSTI)

This study examines the dependence of surface albedo on solar zenith angle (SZA) over snow-free land surfaces using the intensive observations of surface shortwave fluxes made by the U.S. Department of Energy Atmospheric Radiation Measurement (...

Fanglin Yang; Kenneth Mitchell; Yu-Tai Hou; Yongjiu Dai; Xubin Zeng; Zhuo Wang; Xin-Zhong Liang

2008-11-01T23:59:59.000Z

305

Polar-azimuthal angle dependent efficiency of different infrared superconducting nanowire single-photon detector designs  

E-Print Network (OSTI)

The illumination-angle-dependent absorptance was determined for three types of superconducting-nanowire singlephoton detector (SNSPD) designs: 1. periodic bare niobium-nitride (NbN) stripes with dimensions of conventional ...

Csete, Maria

306

WAND: Wide-Angle Neutron Diffractometer at HFIR | ORNL Neutron Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

US/Japan Wide-Angle Neutron Diffractometer US/Japan Wide-Angle Neutron Diffractometer WAND Instrument scientist Jaime Fernandez-Baca (left) with a visiting researcher at WAND. The Wide-Angle Neutron Diffractometer (WAND) at the HFIR HB-2C beam tube was designed to provide two specialized data-collection capabilities: (1) fast measurements of medium-resolution powder-diffraction patterns and (2) measurements of diffuse scattering in single crystals using flat-cone geometry. For these purposes, this instrument is equipped with a curved, one-dimensional 3He position-sensitive detector covering 125º of the scattering angle with the focal distance of 71 cm. The sample and detector can be tilted in the flat-cone geometry mode. These features enable measurement of single-crystal diffraction patterns in a short time over a

307

DISCRETE TRANSPARENT BOUNDARY CONDITIONS FOR WIDE ANGLE PARABOLIC EQUATIONS IN UNDERWATER  

E-Print Network (OSTI)

DISCRETE TRANSPARENT BOUNDARY CONDITIONS FOR WIDE ANGLE PARABOLIC EQUATIONS IN UNDERWATER ACOUSTICS "parabolic" equations (WAPEs) in underwater acoustics (assuming cylindrical symmetry). Existing the discretization of transparent bottom boundary conditions. In oceanography one wants to calculate the underwater

Ehrhardt, Matthias

308

Evaluation of LOWTRAN and MODTRAN for use over high zenith angle/long path length viewing.  

E-Print Network (OSTI)

??LOWTRAN and MODTRAN were evaluated in the 2.0-5.5 micron region against field collection data at high zenith angle/long path lengths to determine the degree of (more)

Wright, Jonathan

1991-01-01T23:59:59.000Z

309

Bio-SANS: the Biological Small-Angle Neutron Scattering Instrument...  

NLE Websites -- All DOE Office Websites (Extended Search)

Biological Small-Angle Neutron Scattering Instrument at HFIR Detector tanks for the new SANS instruments at HFIR. The Bio-SANS detector is on the right. Detector tanks for the SANS...

310

A system for optimizing interior daylight distribution using reflective Venetian blinds with independent blind angle control  

E-Print Network (OSTI)

An operational algorithm for blind angle control is developed to optimize the daylighting performance of a system of reflective Venetian blinds. Numerical modeling and experiment confirm that independent control of alternating ...

McGuire, Molly E

2005-01-01T23:59:59.000Z

311

Astrophysical Implications of the QCD Phase Transition  

Science Conference Proceedings (OSTI)

The possible role of a first order QCD phase transition at nonvanishing quark chemical potential and temperature for cold neutron stars and for supernovae is delineated. For cold neutron stars, we use the NJL model with a nonvanishing color superconducting pairing gap, which describes the phase transition to the 2SC and the CFL quark matter phases at high baryon densities. We demonstrate that these two phase transitions can both be present in the core of neutron stars and that they lead to the appearance of a third family of solution for compact stars. In particular, a core of CFL quark matter can be present in stable compact star configurations when slightly adjusting the vacuum pressure to the onset of the chiral phase transition from the hadronic model to the NJL model. We show that a strong first order phase transition can have a strong impact on the dynamics of core collapse supernovae. If the QCD phase transition sets in shortly after the first bounce, a second outgoing shock wave can be generated which leads to an explosion. The presence of the QCD phase transition can be read off from the neutrino and antineutrino signal of the supernova.

Schaffner-Bielich, J. [Ruprecht-Karls-Universitaet, Heidelberg, Germany; Sagert, I. [Goethe University, Frankfurt, Germany; Hempel, M. [Goethe University, Frankfurt, Germany; Pagliara, G. [Ruprecht-Karls-Universitaet, Heidelberg, Germany; Fischer, T. [University of Basel; Mezzacappa, Anthony [ORNL; Thielemann, Friedrich-Karl W. [Universitat Basel, Switzerland; Liebendoerfer, Matthias [Universitat Basel, Switzerland

2009-01-01T23:59:59.000Z

312

Growth Kinetics of Lipid-Based Nanodiscs to Unilamellar Vesicles: A Time-Resolved Small Angle Neutron Scattering (SANS) Study  

Science Conference Proceedings (OSTI)

Mixtures of dimyristoyl-phosphatidylcholine (DMPC), dimyristoyl-phosphatidylglycerol (DMPG) and dihexanoylphosphatidylcholine (DHPC) in aqueous solutions spontaneously form monodisperse, bilayered nanodiscs (also known as bicelles ) at or below the melting transition temperature of DMPC (TM ~23 C). In dilute systems above the main transition temperature TM of DMPC, bicelles coalesce (increasing their diameter) and eventually self-fold into unilamellar vesicles (ULVs). Time resolved small angle neutron scattering was used to study the growth kinetics of nanodiscs below and equal to TM over a period of hours as a function of temperature at two lipid concentrations in presence or absence of NaCl salt. Bicelles seem to undergo a sudden initial growth phase with increased temperature, which is then followed by a slower reaction-limited growth phase that depends on ionic strength, lipid concentration and temperature. The bicelle interaction energy was derived from the colloidal theory of Derjaguin and Landau, and Verwey and Overbeek (DLVO). While the calculated total energy between discs is attractive and proportional to their growth rate, a more detailed mechanism is proposed to describe the mechanism of disc coalescence. After annealing at low temperature (low-T), samples were heated to 50 C in order to promote the formation of ULVs. Although the low-T annealing of samples has only a marginal effect on the mean size of end-state ULVs, it does affect their polydispersity, which increases with increased T, presumably driven by the entropy of the system.

Mahabir, Suanne [University of Western Ontario, The; Small, Darcy [University of Western Ontario, The; Li, Ming [University of Connecticut, Storrs; Wan, Wankei [University of Western Ontario, The; Kucerka, Norbert [Canadian Neutron Beam Centre and Comelius University (Slovakia); Littrell, Ken [ORNL; Katsaras, John [ORNL; Nieh, Mu-Ping [University of Connecticut, Storrs

2013-01-01T23:59:59.000Z

313

Excursions in Chemical Dynamics  

E-Print Network (OSTI)

2009). [118] F. A. Cotton, Chemical Applications of GroupExcursions in Chemical Dynamics by Shervin Fatehi AFall 2010 Excursions in Chemical Dynamics Copyright 2010 by

Fatehi, Shervin

2010-01-01T23:59:59.000Z

314

Angle-resolved scattering spectroscopy of explosives using an external cavity quantum cascade laser  

Science Conference Proceedings (OSTI)

Investigation of angle-resolved scattering from solid explosives residues on a car door for non-contact sensing geometries. Illumination with a mid-infrared external cavity quantum cascade laser tuning between 7 and 8 microns was detected both with a sensitive single point detector and a hyperspectral imaging camera. Spectral scattering phenomena were discussed and possibilities for hyperspectral imaging at large scattering angles were outlined.

Suter, Jonathan D.; Bernacki, Bruce E.; Phillips, Mark C.

2012-04-01T23:59:59.000Z

315

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

Science Conference Proceedings (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a propagating turbidite complex through the use of hydraulically-fractured horizontal or high-angle wells. The combination of a horizontal or high-angled well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thininterbedded layers and the well bore.

Mike L. Laue

1997-05-08T23:59:59.000Z

316

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

Science Conference Proceedings (OSTI)

This project attempts to demonstrate the effectivensss of exploiting thin-layered, low energy deposits at the distal margin of a propagating turbinite complex through u se of hydraulically fractgured horizontal of high-angle wells. TGhe combinaton of a horizontal or high-angle weoo and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.

Mike L. Laue

1998-02-05T23:59:59.000Z

317

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

Science Conference Proceedings (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low energy deposits at the distal end of a protruding turbidite complex through use of hydraulically fractured horizontal of high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than conventional vertical wells while maintaining vertical communication between thin interbedded layers and the well bore.

Mike L. Laue

1998-05-29T23:59:59.000Z

318

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures  

Science Conference Proceedings (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.

Laue, M.L.

1999-11-01T23:59:59.000Z

319

Topological field theory of dynamical systems  

SciTech Connect

Here, it is shown that the path-integral representation of any stochastic or deterministic continuous-time dynamical model is a cohomological or Witten-type topological field theory, i.e., a model with global topological supersymmetry (Q-symmetry). As many other supersymmetries, Q-symmetry must be perturbatively stable due to what is generically known as non-renormalization theorems. As a result, all (equilibrium) dynamical models are divided into three major categories: Markovian models with unbroken Q-symmetry, chaotic models with Q-symmetry spontaneously broken on the mean-field level by, e.g., fractal invariant sets (e.g., strange attractors), and intermittent or self-organized critical (SOC) models with Q-symmetry dynamically broken by the condensation of instanton-antiinstanton configurations (earthquakes, avalanches, etc.) SOC is a full-dimensional phase separating chaos and Markovian dynamics. In the deterministic limit, however, antiinstantons disappear and SOC collapses into the 'edge of chaos.' Goldstone theorem stands behind spatio-temporal self-similarity of Q-broken phases known under such names as algebraic statistics of avalanches, 1/f noise, sensitivity to initial conditions, etc. Other fundamental differences of Q-broken phases is that they can be effectively viewed as quantum dynamics and that they must also have time-reversal symmetry spontaneously broken. Q-symmetry breaking in non-equilibrium situations (quenches, Barkhausen effect, etc.) is also briefly discussed.

Ovchinnikov, Igor V. [Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, California 90095-1594 (United States)

2012-09-15T23:59:59.000Z

320

The Price of Synchrony: Resistive Losses due to Phase Synchronization in Power Networks  

E-Print Network (OSTI)

We investigate the total resistive losses incurred in returning a power network of identical generators to a synchronous state following a transient stability event or in maintaining this state in the presence of persistent stochastic disturbances. We formulate this cost as the input-output $H^2$ norm of a linear dynamical system with distributed disturbances. We derive an expression for the total resistive losses that scales with the size of the network as well as properties of the generators and power lines, but is independent of the network topology. This topologically invariant scaling of what we term the price of synchrony is in contrast to typical power system stability notions like rate of convergence or the region of attraction for rotor-angle stability. Our result indicates that highly connected power networks, whilst desirable for higher phase synchrony, do not offer an advantage in terms of the total resistive power losses needed to achieve this synchrony. Furthermore, if power flow is the mechanism used to achieve synchrony in highly-distributed-generation networks, the cost increases unboundedly with the number of generators.

Bassam Bamieh; Dennice F. Gayme

2012-09-21T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

The role of viscoelastic contrast in orientation selection of block copolymer lamellar phases under oscillatory shear  

E-Print Network (OSTI)

The mesoscale rheology of a lamellar phase of a block copolymer is modeled as a structured fluid of uniaxial symmetry. The model predicts a viscoelastic response that depends on the angle between the the local lamellar planes and velocity gradients. We focus on the stability under oscillatory shear of a two layer configuration comprising a parallel and a perpendicularly oriented domain, so that the two layers have a different viscoelastic modulus $G^{*}(\\omega)$. A long wave, low Reynolds number expansion is introduced to analytically obtain the region of stability. When the response of the two layers is purely viscous, we recover earlier results according to which the interface is unstable for non zero Reynolds number flows when the thinner layer is more viscous. On the other hand, when viscoelasticity is included, we find that the interface can become unstable even for zero Reynolds number. The interfacial instability is argued to dynamically favor perpendicular relative to parallel orientation, and hence we suggest that the perpendicular orientation would be selected in a multi domain configuration in the range of frequency $\\omega$ in which viscoelastic contrast among orientations is appreciable.

Chi-Deuk Yoo; Jorge Vinals

2013-01-10T23:59:59.000Z

322

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated  

DOE Data Explorer (OSTI)

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated

Connor Flynn

323

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated  

DOE Data Explorer (OSTI)

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated

Connor Flynn

324

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated  

SciTech Connect

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, low-sun angles [a0 data is uncalibrated

Connor Flynn

2011-03-22T23:59:59.000Z

325

ARM: Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated  

SciTech Connect

Shortwave Array Spectroradiometer-Hemispheric, Near-InfraRed channel, high-sun angles [a0 data is uncalibrated

Connor Flynn

2011-03-22T23:59:59.000Z

326

Research of Dynamic Voltage Restorer Based on Repetitive Control Strategy  

Science Conference Proceedings (OSTI)

This paper introduces a dynamic voltage restorer with independent three-phase structure, which is controlled on repetitive control strategy. Computer simulation of the whole repetitive control system is performed by Matlab/Simulink, and the results show ... Keywords: Dynamic Voltage Restorer, Repetitive Control, Voltage Sag

Tianyu Liu

2012-10-01T23:59:59.000Z

327

Dynamic reduction, Version 1. 0  

SciTech Connect

This report describes the theoretical background of the EPRI Dynamic Reduction DYNRED V 1.0. EPRI initiated research under project RP763 to develop the original reduction program DYNEQU. This program was the first to be based on the concept of aggregating of coherent groups of synchronous generators into a single equivalent generator model. While technically advanced, DYNEQU proved difficult to use. Since then, the stability problems encountered in power system planning and operations have changed. The emphasis on first swing transient stability has been replaced by emphasis on inter-area oscillations and voltage stability. The method of identification of coherent generators used in DYNEQU is based on the comparison of rotor angle swings, in a linearized system model, following a fault. It has been shown that this method of coherency identification is good for first swing stability. For inter-area oscillation studies, this method of generator aggregation is less accurate. Far better, are identification methods based on the structure of the power system. Because of these changes in the requirements for reduced order power system models, a new dynamic reduction program (DYNRED) has been developed under EPRI project RP2447-1. It is coherency based, as is DYNEQU, but it has structurally based coherency identification methods in addition to the method used in DYNEQU. This report describes the techniques used in DYNRED, that is: Coherency Identification; Network Reduction; Method of Aggregation, Generator Aggregation, Excitation Aggregation, Primemover/Governor Aggregation. An example of the application of DYNRED to the reduction of a large interconnected power system model is also presented. DYNRED uses the special modeling and network solution techniques developed to enable systems having up to 12,000 bus to be studied. Dynamic data is completely compatible between MASS, PEALS, and the EPRI Extended Transient Midterm Stability Program (ETMSP).

Rogers, G.J.; Wong, D.Y.; Ottevangers, J.; Wang, L. (Ontario Hydro, Toronto, ON (Canada))

1993-04-01T23:59:59.000Z

328

Geometric phases of the Faraday rotation of electromagnetic waves in magnetized plasmas  

Science Conference Proceedings (OSTI)

Geometric phases of circularly polarized electromagnetic waves in nonuniform magnetized plasmas is studied theoretically. The variation of the propagation direction of circularly polarized waves results in a geometric phase, which also contributes to the Faraday rotation, in addition to the standard dynamical phase. The origin and properties of the geometric phase are investigated. The influence of the geometric phase to plasma diagnostics using the Faraday rotation is discussed as an application of the theory.

Liu Jian [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Qin Hong [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

2012-10-15T23:59:59.000Z

329

Determining the angles of break of the mining subsidence basin by the neural network with genetic algorithm  

Science Conference Proceedings (OSTI)

The angle of break is a key factor that determines the mining damage extent of the surface in a mine, and it is also used to depict the characteristics of the mining subsidence basin. The geological and mining factors that influence the angle of break ... Keywords: angle of break, genetic algorithm, neural network, subsidence basin

Hua-bin Chai

2010-03-01T23:59:59.000Z

330

Small-angle Compton Scattering to Determine the Depth of a Radioactive Source in Matter  

SciTech Connect

A gamma-ray peak in a spectrum is often accompanied by a discontinuity in the Compton continuum at the peak. The Compton continuum results from Compton scattering in the detector. The discontinuity at a peak results from small-angle Compton scattering by the gamma rays in matter situated directly between the gamma-ray source and the detector. The magnitude of this discontinuity with respect to the gamma-ray peak is therefore an indicator of the amount of material or shielding between the gamma-ray source and the detector. This small-angle scattering was used to determine the depth of highly-enriched uranium (HEU) solution standards in a concrete floor mockup. The empirical results of the use of this small-angle scattering discontinuity in a concrete floor experiment will be described. A Monte Carlo calculation of the experiment will also be described. In addition, the depth determined from small-angle scattering was used in conjunction with differential attenuation to more accurately measure the uranium content of the mockup. Following these empirical results, the theory of small-angle scattering will be discussed. The magnitude of the discontinuity compared to the peak count rate is directly related to the depth of the gamma-ray source in matter. This relation can be described by relatively simple mathematical expressions. This is the first instance that we are aware of in which the small-angle Compton scattering has been used to determine the depth of a radioactive source. Furthermore this is the first development of the theoretical expressions for the magnitude of the small-angle scattering discontinuity.

Oberer, R. B.; Gunn, C. A.; Chiang, L. G.; Valiga, R. E.; Cantrell, J. A.

2011-04-01T23:59:59.000Z

331

Ray-tracing studies for a whole-viewing-angle retroreflector  

SciTech Connect

The APS Survey and Alignment team uses LEICA laser trackers for the majority of their alignment tasks. These instruments utilize several different retroreflectors for tracking the path of the laser interferometer. Currently in use are open-air corner cubes with an acceptance angle of {+-}20{degree}, corner cube prisms with an acceptance angle of {+-}50{degree}, and a Cat's eye with an acceptance angle of {+-}60{degree}. Best measurement results can be achieved by using an open-air corner cube that eliminates the need for the laser beam to travel through a different medium before it returns to the instrument detector. However, the trade off is a small acceptance angle. In order to overcome the limitations of the small acceptance angles, Takatsuji et al. has proposed the creation of a full-viewing-angle retroreflector. Based on the notion that the radius R{sub 1} of a common Cat's eye is proportional to R{sub 2}, one can write: R{sub 1} = (n {minus} 1)R{sub 2}. In the case that n, the refractive index of glass, equals 2, the radii R{sub 1} and R{sub 2} are identical, and one can create a solid sphere Cat's eye. This design has the advantages that no adhesives are used to bond the two hemispheres together, misalignments between the hemispheres are not an issue, and most importantly, larger acceptance angles are possible. This paper shows the results of their ray tracing calculations characterizing the geometrical optics.

Yang, B.; Friedsam, H.

2000-02-02T23:59:59.000Z

332

System dynamics model for simulation of the software inspection process  

Science Conference Proceedings (OSTI)

Repairing a defect in the late phases of software development can be a hundred times more expensive than finding and fixing it during the requirements and design phase. Software inspection is a technique that may be used to aid in the identification ... Keywords: defect detection, software inspection, system dynamics

Jailton Jr. De Sousa Coelho, Jos Luis Braga, Bernardo Giori Ambrsio

2013-08-01T23:59:59.000Z

333

Reaction Dynamics with Exotic Beams  

E-Print Network (OSTI)

We review the new possibilities offered by the reaction dynamics of asymmetric heavy ion collisions, using stable and unstable beams. We show that it represents a rather unique tool to probe regions of highly Asymmetric Nuclear Matter ($ANM$) in compressed as well as dilute phases, and to test the in-medium isovector interaction for high momentum nucleons. The focus is on a detailed study of the symmetry term of the nuclear Equation of State ($EOS$) in regions far away from saturation conditions but always under laboratory controlled conditions. Thermodynamic properties of $ANM$ are surveyed starting from nonrelativistic and relativistic effective interactions. In the relativistic case the role of the isovector scalar $\\delta$-meson is stressed. The qualitative new features of the liquid-gas phase transition, "diffusive" instability and isospin distillation, are discussed. The results of ab-initio simulations of n-rich, n-poor, heavy ion collisions, using stochastic isospin dependent transport equations, are ...

Baran, V; Greco, V; Di Toro, M

2004-01-01T23:59:59.000Z

334

Pressure tunes electrical resistivity by four orders of magnitude in amorphous Ge[subscript 2]Sb[subscript 2]Te[subscript 5] phase-change memory alloy  

Science Conference Proceedings (OSTI)

Ge-Sb-Te-based phase-change memory is one of the most promising candidates to succeed the current flash memories. The application of phase-change materials for data storage and memory devices takes advantage of the fast phase transition (on the order of nanoseconds) and the large property contrasts (e.g., several orders of magnitude difference in electrical resistivity) between the amorphous and the crystalline states. Despite the importance of Ge-Sb-Te alloys and the intense research they have received, the possible phases in the temperature-pressure diagram, as well as the corresponding structure-property correlations, remain to be systematically explored. In this study, by subjecting the amorphous Ge{sub 2}Sb{sub 2}Te{sub 5} (a-GST) to hydrostatic-like pressure (P), the thermodynamic variable alternative to temperature, we are able to tune its electrical resistivity by several orders of magnitude, similar to the resistivity contrast corresponding to the usually investigated amorphous-to-crystalline (a-GST to rock-salt GST) transition used in current phase-change memories. In particular, the electrical resistivity drops precipitously in the P = 0 to 8 GPa regime. A prominent structural signature representing the underlying evolution in atomic arrangements and bonding in this pressure regime, as revealed by the ab initio molecular dynamics simulations, is the reduction of low-electron-density regions, which contributes to the narrowing of band gap and delocalization of trapped electrons. At P > 8 GPa, we have observed major changes of the average local structures (bond angle and coordination numbers), gradually transforming the a-GST into a high-density, metallic-like state. This high-pressure glass is characterized by local motifs that bear similarities to the body-centered-cubic GST (bcc-GST) it eventually crystallizes into at 28 GPa, and hence represents a bcc-type polyamorph of a-GST.

Xu, M.; Cheng, Y.Q.; Wang, L.; Sheng, H.W.; Meng, Y.; Yang, W.G.; Hang, X.D.; Ma, E. (Beijing U); (JHU); (CIW); (George Mason)

2012-05-22T23:59:59.000Z

335

116 Interfacial Phase Effect on Static-Dynamic Mechanical ...  

Science Conference Proceedings (OSTI)

005 Calcium Phosphates for Drug Carrier: Adsorption and Release Kinetics of Drugs ... 058 Properties Optimization of Refractory Mineral Resources in China.

336

Bayesian Estimator for Angle Recovery: Event Classification and Reconstruction in Positron Emission Tomography  

SciTech Connect

PET at the highest level is an inverse problem: reconstruct the location of the emission (which localize biological function) from detected photons. Ideally, one would like to directly measure an annihilation photon's incident direction on the detector. In the developed algorithm, Bayesian Estimation for Angle Recovery (BEAR), we utilized the increased information gathered from localizing photon interactions in the detector and developed a Bayesian estimator for a photon's incident direction. Probability distribution functions (PDFs) were filled using an interaction energy weighted mean or center of mass (COM) reference space, which had the following computational advantages: (1) a significant reduction in the size of the data in measurement space, making further manipulation and searches faster (2) the construction of COM space does not depend on measurement location, it takes advantage of measurement symmetries, and data can be added to the training set without knowledge and recalculation of prior training data, (3) calculation of posterior probability map is fully parallelizable, it can scale to any number of processors. These PDFs were used to estimate the point spread function (PSF) in incident angle space for (i) algorithm assessment and (ii) to provide probability selection criteria for classification. The algorithm calculates both the incident {theta} and {phi} angle, with {approx}16 degrees RMS in both angles, limiting the incoming direction to a narrow cone. Feature size did not improve using the BEAR algorithm as an angle filter, but the contrast ratio improved 40% on average.

Foudray, Angela M K [Stanford University Molecular Imaging Program at Stanford Department of Radiology Palo Alto, CA (United States); University of California, San Diego Department of Physics La Jolla, CA (United States); Levin, Craig S [Stanford University Molecular Imaging Program at Stanford Department of Radiology Palo Alto, CA (United States)

2007-11-13T23:59:59.000Z

337

Aging, phase ordering and conformal invariance  

E-Print Network (OSTI)

In a variety of systems which exhibit aging, the two-time response function scales as $R(t,s)\\approx s^{-1-a} f(t/s)$. We argue that dynamical scaling can be extended towards conformal invariance, obtaining thus the explicit form of the scaling function $f$. This quantitative prediction is confirmed in several spin systems, both for $Tphase ordering) and $T=T_c$ (non-equilibrium critical dynamics). The 2D and 3D Ising models with Glauber dynamics are studied numerically, while exact results are available for the spherical model with a non-conserved order parameter, both for short-ranged and long-ranged interactions, as well as for the mean-field spherical spin glass.

Malte Henkel; Michel Pleimling; Claude Godreche; Jean-Marc Luck

2001-07-13T23:59:59.000Z

338

Ni coarsening in the three-phase solid oxide fuel cell anode - a phase-field simulation study  

E-Print Network (OSTI)

Ni coarsening in Ni-yttria stabilized zirconia (YSZ) solid oxide fuel cell anodes is considered a major reason for anode degradation. We present a predictive, quantative modeling framework based on the phase-field approach to systematically examine coarsening kinetics in such anodes. The initial structures for simulations are experimentally acquired functional layers of anodes. Sample size effects and error analysis of contact angles are examined. Three phase boundary (TPB) lengths and Ni surface areas are quantatively identified on the basis of the active, dead-end, and isolated phase clusters throughout coarsening. Tortuosity evolution of the pores is also investigated. We find that phase clusters with larger characteristic length evolve slower than those with smaller length scales. As a result, coarsening has small positive effects on transport, and impacts less on the active Ni surface area than the total counter part. TPBs, however, are found to be sensitive to local morphological features and are only i...

Chen, Hsun-Yi; Cronin, J Scott; Wilson, James R; Barnett, Scott A; Thornton, Katsuyo

2012-01-01T23:59:59.000Z

339

Power system identification toolbox: Phase two progress  

Science Conference Proceedings (OSTI)

This report describes current progress on a project funded by the Bonneville Power Administration (BPA) to develop a set of state-of-the-art analysis software (termed the Power System Identification [PSI] Toolbox) for fitting dynamic models to measured data. The project is being conducted as a three-phase effort. The first phase, completed in late 1992, involved investigating the characteristics of the analysis techniques by evaluating existing software and developing guidelines for best use. Phase Two includes extending current software, developing new analysis algorithms and software, and demonstrating and developing applications. The final phase will focus on reorganizing the software into a modular collection of documented computer programs and developing user manuals with instruction and application guidelines. Phase Two is approximately 50% complete; progress to date and a vision for the final product of the PSI Toolbox are described. The needs of the power industry for specialized system identification methods are particularly acute. The industry is currently pushing to operate transmission systems much closer to theoretical limits by using real-time, large-scale control systems to dictate power flows and maintain dynamic stability. Reliably maintaining stability requires extensive system-dynamic modeling and analysis capability, including measurement-based methods. To serve this need, the BPA has developed specialized system-identification computer codes through in-house efforts and university contract research over the last several years. To make full integrated use of the codes, as well as other techniques, the BPA has commissioned Pacific Northwest Laboratory (PNL) to further develop the codes and techniques into the PSI Toolbox.

Trudnowski, D.J.

1994-08-01T23:59:59.000Z

340

Self-tuning Fuzzy Control Method Based on the Trajectory Performance of the Phase Plane  

E-Print Network (OSTI)

The phase plane is already an important method to design fuzzy control systems and analyze their stability. The concept of the real-time response trajectory characteristic vectors and angles between the real-time characteristic vectors on the phase plane are put forward in this paper according to the analysis of the response trajectory performance on the phase plane of a fuzzy control system. The method of rule self-tuning fuzzy control based on the response trajectory performance on phase plane is presented by analyzing the characteristics of angles between the real-time characteristic vectors. The simulation results show that the method is not only capable of increasing greatly the ability to identify and describe the plant in small error, reducing the overshoot, settle time greatly and improving the convergence speed of the fuzzy control system, but also possesses a simple arithmetic and does not require much more storage space and calculation time.

Zhang, J.; Chen, Y.; Xiong, J.

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

A Generic Dynamic Emulator  

E-Print Network (OSTI)

In applied sciences, we often deal with deterministic simulation models that are too slow for simulation-intensive tasks such as calibration or real-time control. In this paper, an emulator for a generic dynamic model, given by a system of ordinary non-linear differential equations, is developed. The non-linear differential equations are linearized and Gaussian white noise is added to account for the non-linearities. The resulting linear stochastic system is conditioned on a set of solutions of the non-linear equations that have been calculated prior to the emulation. A path-integral approach is used to derive the Gaussian distribution of the emulated solution. The solution reveals that most of the computational burden can be shifted to the conditioning phase of the emulator and the complexity of the actual emulation step only scales like $\\mathcal O(Nnm^2)$, where $N$ is the number of time-points at which the solution is to be emulated, $n$ the number of solutions the emulator is conditioned on and $m$ the n...

Albert, Carlo

2011-01-01T23:59:59.000Z

342

Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle  

Open Energy Info (EERE)

Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Aerial Photography, NAS Fallon Geothermal Exploration Project, Dixie Valley, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Aerial Photography, NAS Fallon Geothermal Exploration Project, Dixie Valley, Nevada Abstract The goal of this study is to map and characterize Quaternary faults in southern Dixie Valley for the Department of the Navy Geothermal Program Office's NAS Fallon Geothermal Exploration Project. We will use this information to better characterize the regional structure and geothermal resource potential of the area,with a focus on determining the structural

343

EQ-SANS: the Extended Q-Range Small-Angle Neutron Scattering Diffractometer  

NLE Websites -- All DOE Office Websites (Extended Search)

The Extended Q-Range Small-Angle Neutron Scattering Diffractometer at SNS The Extended Q-Range Small-Angle Neutron Scattering Diffractometer at SNS Extended Q-Range Small Angle Diffractometer EQ-SANS detector array The EQ-SANS Diffractometer is designed to study non-crystalline, nano-sized materials in solid, liquid, or gas forms such as polymers, micelles, proteins, and other large biological molecular complexes in solution. It offers high neutron flux, high wavelength resolution (precision), and wide Q-coverage. EQSANS is located on beam line 6, viewing the top-downstream, coupled supercritical hydrogen moderator. It has a curved multichannel beam bender to avoid the direct line of sight of the moderator, which cleans out the background from the prompt neutron pulse quite effectively. The cutoff wavelength of the optics is ~1.5 Å. Above this minimum wavelength, the

344

Combustion Process in a Spark Ignition Engine: Analysis of Cyclic Maximum Pressure and Peak Pressure Angle  

E-Print Network (OSTI)

In this paper we analyze the cycle-to-cycle variations of maximum pressure $p_{max}$ and peak pressure angle $\\alpha_{pmax}$ in a four-cylinder spark ignition engine. We examine the experimental time series of $p_{max}$ and $\\alpha_{pmax}$ for three different spark advance angles. Using standard statistical techniques such as return maps and histograms we show that depending on the spark advance angle, there are significant differences in the fluctuations of $p_{max}$ and $\\alpha_{pmax}$. We also calculate the multiscale entropy of the various time series to estimate the effect of randomness in these fluctuations. Finally, we explain how the information on both $p_{max}$ and $\\alpha_{pmax}$ can be used to develop optimal strategies for controlling the combustion process and improving engine performance.

G. Litak; T. Kaminski; J. Czarnigowski; A. K. Sen; M. Wendeker

2006-11-29T23:59:59.000Z

345

Dynamics of Jupiter Trojans during the 2:1 mean motion resonance crossing of Jupiter and Saturn  

E-Print Network (OSTI)

We study the dynamics of Jupiter Trojans in the early phase of the Solar system while the outer planets migrated due to their interaction with the planetesimal disk.

Marzari, F

2007-01-01T23:59:59.000Z

346

Rf phase measurement at PHERMEX (Pulsed High Energy Radiographic Machine Emitting X-Rays) using time-to-digital converters  

Science Conference Proceedings (OSTI)

Recent advances in time-to-digital converters (TDCs) have made 50-MHz rf phase measurement possible without the use of double-balanced mixers. These advances allow zero crossing discriminators to be used in conjunction with fast CAMAC TDCs to make amplitude-independent phase measurements. This method uses a time interval proportional to the phase angle, thus eliminating any of the calculations and calibration required with double-balanced mixers. 4 refs., 1 fig., 1 tab.

Watson, S.A.; Jennings, G.R.; Moir, D.C.

1989-01-01T23:59:59.000Z

347

Methods, systems and apparatus for optimization of third harmonic current injection in a multi-phase machine  

DOE Patents (OSTI)

Methods, system and apparatus are provided for increasing voltage utilization in a five-phase vector controlled machine drive system that employs third harmonic current injection to increase torque and power output by a five-phase machine. To do so, a fundamental current angle of a fundamental current vector is optimized for each particular torque-speed of operating point of the five-phase machine.

Gallegos-Lopez, Gabriel

2012-10-02T23:59:59.000Z

348

Dynamics of hot and dense nuclear and partonic matter  

Science Conference Proceedings (OSTI)

The dynamics of hot and dense nuclear matter is discussed from the microscopic transport point of view. The basic concepts of the Hadron-String-Dynamical transport model (HSD)-derived from Kadanoff-Baym equations in phase phase-are presented as well as 'highlights' of HSD results for different observables in heavy-ion collisions from 100 A MeV (SIS) to 21 A TeV(RHIC) energies. Furthermore, a novel extension of the HSD model for the description of the partonic phase-the Parton-Hadron-String-Dynamics (PHSD) approach-is introduced. PHSD includes a nontrivial partonic equation of state-in line with lattice QCD-as well as covariant transition rates from partonic to hadronic degrees of freedom. The sensitivity of hadronic observables to the partonic phase is demonstrated for relativistic heavy-ion collisions from the FAIR/NICA up to the RHIC energy regime.

Bratkovskaya, E. L., E-mail: Elena.Bratkovskaya@th.physik.uni-frankfurt.de [Frankfurt University, Institute for Theoretical Physics (Germany); Cassing, W. [Giessen University, Institute for Theoretical Physics (Germany); Linnyk, O. [Frankfurt University, Institute for Theoretical Physics (Germany); Konchakovski, V. P. [Giessen University, Institute for Theoretical Physics (Germany); Voronyuk, V. [Frankfurt University, FIAS (Germany); Ozvenchuk, V. [Frankfurt University, Institute for Theoretical Physics (Germany)

2012-06-15T23:59:59.000Z

349

Low Energy Sputtering Events at Free Surfaces near Anti-Phase and Grain Boundaries in Ni3Al  

Science Conference Proceedings (OSTI)

Atomic recoil events on free surfaces orthogonal to two different anti-phase boundaries (APBs) and two grain boundaries (GBs) in Ni3Al are simulated using molecular dynamics methods. The threshold energy for sputtering, Esp, and adatom creation, Ead, are determined as a function of recoil direction. The study is relevant to FEG STEM experiments on preferential Al sputtering and/or enhancement of the Ni-Al ratio near boundaries. Surfaces intersected by {l_brace}110{r_brace} and {l_brace}111{r_brace} APBs have minimum Esp of 6.5 eV for an Al atom on the Ni-Al mixed (M) surface, which is close to the value of 6.0 eV for a perfect M surface. High values of Esp of an Al atom generally occur at large angle to the surface normal and depend strongly on the detailed atomic configuration of the surface. The mean Esp averaged over all recoil directions reveals that APBs have a small effect on the threshold sputtering. However, the results for Ead imply that an electron beam could create more Al adatoms on surfaces intersected by APBs than on those without. The equilibrium, minimum energy structures for a (001) surface intersected by either Sigma5[001](210) or Sigma25[001](340) symmetric tilt grain boundaries are computed. Esp for surface Al atoms near these GBs increases monotonically with increasing recoil angle to the surface normal, with a minimum value which is only about 1 eV different from that obtained for a perfect surface. Temperature up to 300 K has no effect on this result. It is concluded that the experimental observations of preferential sputtering are due to effects beyond those for Esp studied here. Possible reasons for this are discussed.

Gao, Fei; Bacon, David J.; Lai, Wenshen; Kurtz, Richard J.

2006-09-21T23:59:59.000Z

350

Pitch angle scattering of relativistic electrons from stationary magnetic waves: Continuous Markov process and quasilinear theory  

Science Conference Proceedings (OSTI)

We develop a Markov process theory of charged particle scattering from stationary, transverse, magnetic waves. We examine approximations that lead to quasilinear theory, in particular the resonant diffusion approximation. We find that, when appropriate, the resonant diffusion approximation simplifies the result of the weak turbulence approximation without significant further restricting the regime of applicability. We also explore a theory generated by expanding drift and diffusion rates in terms of a presumed small correlation time. This small correlation time expansion leads to results valid for relatively small pitch angle and large wave energy density - a regime that may govern pitch angle scattering of high-energy electrons into the geomagnetic loss cone.

Lemons, Don S. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2012-01-15T23:59:59.000Z

351

Pitch angle resolved measurements of escaping charged fusion products in TFTR  

SciTech Connect

Measurements of the flux of charged fusion products escaping from the TFTR plasma have been made with a new type of detector which can resolve the particle flux vs. pitch angle, energy, and time. The design of this detector is described, and results from the 1987 TFTR run are presented. These results are roughly consistent with predictions from a simple first-orbit particle loss model with respect to the pitch angle, energy, time, and plasma current dependence of the signals. 11 refs., 9 figs.

Zweben, S.J.

1989-01-01T23:59:59.000Z

352

Reaction Dynamics with Exotic Beams  

E-Print Network (OSTI)

We review the new possibilities offered by the reaction dynamics of asymmetric heavy ion collisions, using stable and unstable beams. We show that it represents a rather unique tool to probe regions of highly Asymmetric Nuclear Matter ($ANM$) in compressed as well as dilute phases, and to test the in-medium isovector interaction for high momentum nucleons. The focus is on a detailed study of the symmetry term of the nuclear Equation of State ($EOS$) in regions far away from saturation conditions but always under laboratory controlled conditions. Thermodynamic properties of $ANM$ are surveyed starting from nonrelativistic and relativistic effective interactions. In the relativistic case the role of the isovector scalar $\\delta$-meson is stressed. The qualitative new features of the liquid-gas phase transition, "diffusive" instability and isospin distillation, are discussed. The results of ab-initio simulations of n-rich, n-poor, heavy ion collisions, using stochastic isospin dependent transport equations, are analysed as a function of beam energy and centrality. The isospin dynamics plays an important role in all steps of the reaction, from prompt nucleon emissions to the final fragments. The isospin diffusion is also of large interest, due to the interplay of asymmetry and density gradients. In relativistic collisions, the possibility of a direct study of the covariant structure of the effective nucleon interaction is shown. Results are discussed for particle production, collective flows and iso-transparency. Perspectives of further developments of the field, in theory as well as in experiment, are presented.

V. Baran; M. Colonna; V. Greco; M. Di Toro

2004-12-15T23:59:59.000Z

353

Chaotic eigenfunctions in phase space  

E-Print Network (OSTI)

We study individual eigenstates of quantized area-preserving maps on the 2-torus which are classically chaotic. In order to analyze their semiclassical behavior, we use the Bargmann-Husimi representations for quantum states, as well as their stellar parametrization, which encodes states through a minimal set of points in phase space (the constellation of zeros of the Husimi density). We rigorously prove that a semiclassical uniform distribution of Husimi densities on the torus entails a similar equidistribution for the corresponding constellations. We deduce from this property a universal behavior for the phase patterns of chaotic Bargmann eigenfunctions, which reminds of the WKB approximation for eigenstates of integrable systems (though in a weaker sense). In order to obtain more precise information on ``chaotic eigenconstellations", we then model their properties by ensembles of random states, generalizing former results on the 2-sphere to the torus geometry. This approach yields statistical predictions for the constellations, which fit quite well the chaotic data. We finally observe that specific dynamical information, e.g. the presence of high peaks (like scars) in Husimi densities, can be recovered from the knowledge of a few long-wavelength Fourier coefficients, which therefore appear as valuable order parameters at the level of individual chaotic eigenfunctions.

S. Nonnenmacher; A. Voros

1997-11-15T23:59:59.000Z

354

NGNP PHASE I REVIEW  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

REVIEW REVIEW NEAC REACTOR TECHNOLOGY SUBCOMMITTEE FINAL REPORT JUNE 15, 2011 EPACT 2005 REQUIREMENTS * FIRST PROJECT PHASE REVIEW-On a determination by the Secretary that the appropriate activities under the first project phase under subsection (b)(1) are nearly complete, the Secretary shall request the NERAC to conduct a comprehensive review of the Project and to report to the Secretary the recommendation of the NERAC concerning whether the Project is ready to proceed to the second project phase under subsection (b)(2) NGNP PROJECT PHASES (1) FIRST PHASE.-A first project phase shall be conducted to- (A) select and validate the appropriate technology under subsection (a)(1); (B) carry out enabling research, development, and demonstration activities on technologies and components under

355

Gymnastics in Phase Space  

SciTech Connect

As accelerator technology advances, the requirements on accelerator beam quality become increasingly demanding. Facing these new demands, the topic of phase space gymnastics is becoming a new focus of accelerator physics R&D. In a phase space gymnastics, the beam's phase space distribution is manipulated and precision tailored to meet the required beam qualities. On the other hand, all realization of such gymnastics will have to obey accelerator physics principles as well as technological limitations. Recent examples of phase space gymnastics include Emittance exchanges, Phase space exchanges, Emittance partitioning, Seeded FELs and Microbunched beams. The emittance related topics of this list are reviewed in this report. The accelerator physics basis, the optics design principles that provide these phase space manipulations, and the possible applications of these gymnastics, are discussed. This fascinating new field promises to be a powerful tool of the future.

Chao, Alexander Wu; /SLAC

2012-03-01T23:59:59.000Z

356

Drum-boiler dynamics  

Science Conference Proceedings (OSTI)

A nonlinear dynamic model for natural circulation drum-boilers is presented. The model describes the complicated dynamics of the drum, downcomer, and riser components. It is derived from first principles, and is characterized by a few physical parameters. ...

K. J. StrM; R. D. Bell

2000-03-01T23:59:59.000Z

357

Dynamic Residential Window prototype  

NLE Websites -- All DOE Office Websites (Extended Search)

to have dynamic seasonal solar control: high solar gains in the winter with high insulation and low solar gains in the summer. Dynamic, high performance products can be based...

358

Crystal phase identification  

DOE Patents (OSTI)

A method and apparatus for determining the crystalline phase and crystalline characteristics of a sample. This invention provides a method and apparatus for unambiguously identifying and determining the crystalline phase and crystalline characteristics of a sample by using an electron beam generator, such as a scanning electron microscope, to obtain a backscattered electron Kikuchi pattern of a sample, and extracting crystallographic and composition data that is matched to database information to provide a quick and automatic method to identify crystalline phases.

Michael, Joseph R. (Albuquerque, NM); Goehner, Raymond P. (Albuquerque, NM); Schlienger, Max E. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

359

Phase Transition - CECM  

E-Print Network (OSTI)

Dec 24, 2003 ... Another example is the order-disorder phases in binary alloy such as brass. The copper and zinc atoms occupy alternate sites in a regular...

360

NGNP PHASE I REVIEW  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

REVIEW NEAC REACTOR TECHNOLOGY SUBCOMMITTEE CURRENT STATUS DECEMBER 9, 2010 EPACT 2005 REQUIREMENTS * FIRST PROJECT PHASE REVIEW-On a determination by the Secretary that the...

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

ARM - Measurement - Cloud phase  

NLE Websites -- All DOE Office Websites (Extended Search)

property that captures the state o f the hydrometeors within a cloud (liquid, ice, or mixed-phase). This is distinct from cloud type that involves property descriptors...

362

Phase Stability II  

Science Conference Proceedings (OSTI)

... and Mo-Pu-U are presented with a discussion on phase identification versus ... the formulation of more robust principles of kinetics and path selection.

363

General Dynamics, Electric Boat  

Science Conference Proceedings (OSTI)

General Dynamics, Electric Boat. NVLAP Lab Code: 100560-0. Address and Contact Information: 75 Eastern Point Road ...

2013-08-16T23:59:59.000Z

364

NIST Photovoltaic carrier dynamics  

Science Conference Proceedings (OSTI)

... carrier dynamics in novel electronic photovoltaic materials being considered and developed for future solar cell and energy capture applications. ...

2013-04-01T23:59:59.000Z

365

Update on Angles and Sides of the CKM Unitarity Triangle from BaBar  

SciTech Connect

We report several recent updates from the BABAR Collaboration on the matrix elements |V{sub cb}|, |V{sub ub}|, and |V{sub td}| of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix, and the angles {beta} and {alpha} of the unitarity triangle. Most results presented here are using the full BABAR {Upsilon}(4S) data set.

Cheng, Chih-hsiang; /Caltech

2011-11-14T23:59:59.000Z

366

Coulomb Correction to the Screening Angle of the Moliere Multiple Scattering Theory  

E-Print Network (OSTI)

High-energy Coulomb correction to the screening angular parameter of the Moliere multiple scattering theory is found. Numerical calculations are presented in the range of nuclear charge from Z=4 to Z=82. Comparison with the Moliere result for the screening angle reveals up to 30% deviation from it for sufficiently heavy elements of the target material.

E. A. Kuraev; O. O. Voskresenskaya; A. V. Tarasov

2012-11-29T23:59:59.000Z

367

Importance of Low-Angle Grain Boundaries in YBa2Cu3O7-? Coated Conductors  

E-Print Network (OSTI)

behaviour of single grain boundaries in YBa2Cu3O7?? with an emphasis on those with misorientation angles less than 10 degrees. This cutoff is chosen following the work of Redwing and Heinig [65, 7] who showed, with some variation with magnetic field...

Durrell, John H; Rutter, Noel Anthony

368

Gaze Estimation for Off-Angle Iris Recognition Based on the Biometric Eye Model  

SciTech Connect

Iris recognition is among the highest accuracy biometrics. However, its accuracy relies on controlled high quality capture data and is negatively affected by several factors such as angle, occlusion, and dilation. Non-ideal iris recognition is a new research focus in biometrics. In this paper, we present a gaze estimation method designed for use in an off-angle iris recognition framework based on the ANONYMIZED biometric eye model. Gaze estimation is an important prerequisite step to correct an off-angle iris images. To achieve the accurate frontal reconstruction of an off-angle iris image, we first need to estimate the eye gaze direction from elliptical features of an iris image. Typically additional information such as well-controlled light sources, head mounted equipment, and multiple cameras are not available. Our approach utilizes only the iris and pupil boundary segmentation allowing it to be applicable to all iris capture hardware. We compare the boundaries with a look-up-table generated by using our biologically inspired biometric eye model and find the closest feature point in the look-up-table to estimate the gaze. Based on the results from real images, the proposed method shows effectiveness in gaze estimation accuracy for our biometric eye model with an average error of approximately 3.5 degrees over a 50 degree range.

Karakaya, Mahmut [ORNL; Barstow, Del R [ORNL; Santos-Villalobos, Hector J [ORNL; Thompson, Joseph W [ORNL; Bolme, David S [ORNL; Boehnen, Chris Bensing [ORNL

2013-01-01T23:59:59.000Z

369

Estimating fish orientation from broadband, limited-angle, multiview, acoustic reflections  

E-Print Network (OSTI)

Estimating fish orientation from broadband, limited-angle, multiview, acoustic reflections Jules S recorded from lateral views of juvenile fish can be used to infer animal orientation. Cali- brated acoustic data were recorded from live fish in a laboratory, while orientation was measured simultaneously via

Jaffe, Jules

370

Small-Angle Neutron Scattering Studies of a-Si:H and a-Si:D  

DOE Green Energy (OSTI)

The heterogeneity of hydrogen and deuterium on the nanometer scale has been probed by samll-angle neutron scattering (SANS) from a-Si:H and a-Si:D films. Films were depsoited by two techniques, plasma-enhanced chemical vapor deposition (PECVD) and hot-wire chemical vapor deposition (HWCVD) using conditions that yield high quality films and devices.

Williamson, D. L.; Marr, D. W. M.; Nelson, B. P.; Iwaniczko, E.; Yang, J.; Yan, B.; Guha, S.

2000-01-01T23:59:59.000Z

371

A Study on Optimum Tilt Angle for Wind Estimation Using Indian MST Radar  

Science Conference Proceedings (OSTI)

The effect of tilt angle on horizontal wind estimation is studied using Indian mesospherestratospheretroposphere (MST) radar located at Gadanki (13.45N, 79.18E). It operates in Doppler beam swinging (DBS) mode with a beamwidth of 3. ...

V. K. Anandan; I. Srinivasa Rao; P. Narasimha Reddy

2008-09-01T23:59:59.000Z

372

Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging  

DOE Patents (OSTI)

Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

Hu, Jian Zhi (Richland, WA); Sears, Jr., Jesse A. (Kennewick, WA); Hoyt, David W. (Richland, WA); Wind, Robert A. (Kennewick, WA)

2009-05-19T23:59:59.000Z

373

Biology and Phase Transition - CECM  

E-Print Network (OSTI)

Dec 24, 2003 ... next up previous. Next: Kaufman and percolation Up: Phase Transition Models in Previous: Phase Transition Models in...

374

Hydrogen and deuterium NMR of solids by magic-angle spinning  

DOE Green Energy (OSTI)

The nuclear magnetic resonance of solids has long been characterized by very large specral broadening which arises from internuclear dipole-dipole coupling or the nuclear electric quadrupole interaction. These couplings can obscure the smaller chemical shift interaction and make that information unavailable. Two important and difficult cases are that of hydrogen and deuterium. The development of cross polarization, heteronuclear radiofrequency decoupling, and coherent averaging of nuclear spin interactions has provided measurement of chemical shift tensors in solids. Recently, double quantum NMR and double quantum decoupling have led to measurement of deuterium and proton chemical shift tensors, respectively. A general problem of these experiments is the overlapping of the tensor powder pattern spectra of magnetically distinct sites which cannot be resolved. In this work, high resolution NMR of hydrogen and deuterium in solids is demonstrated. For both nuclei, the resonances are narrowed to obtain liquid-like isotropic spectra by high frequency rotation of the sample about an axis inclined at the magic angle, ..beta../sub m/ = Arccos (3/sup -1/2/), with respect to the direction of the external magnetic field. For deuterium, the powder spectra were narrowed by over three orders of magnitude by magic angle rotation with precise control of ..beta... A second approach was the observation of deuterium double quantum transitions under magic angle rotation. For hydrogen, magic angle rotation alone could be applied to obtain the isotropic spectrum when H/sub D/ was small. This often occurs naturally when the nuclei are semi-dilute or involved in internal motion. In the general case of large H/sub D/, isotropic spectra were obtained by dilution of /sup 1/H with /sup 2/H combined with magic angle rotation. The resolution obtained represents the practical limit for proton NMR of solids.

Eckman, R.R.

1982-10-01T23:59:59.000Z

375

Phases of N=1 Supersymmetric Chiral Gauge Theories  

SciTech Connect

We analyze the phases of supersymmetric chiral gauge theories with an antisymmetric tensor and (anti)fundamental flavors, in the presence of a classically marginal superpotential deformation. Varying the number of flavors that appear in the superpotential reveals rich infrared chiral dynamics and novel dualities. The dualities are characterized by an infinite family of magnetic duals with arbitrarily large gauge groups describing the same fixed point, correlated with arbitrarily large classical global symmetries that are truncated nonperturbatively. At the origin of moduli space, these theories exhibit a phase with confinement and chiral symmetry breaking, an interacting nonabelian Coulomb phase, and phases where an interacting sector coexists with a sector that either s-confines or is in a free magnetic phase. Properties of these intriguing 'mixed phases' are studied in detail using duality and a-maximization, and the presence of superpotential interactions provides further insights into their formation.

Craig, Nathaniel; /Princeton, Inst. Advanced Study /Rutgers U., Piscataway; Essig, Rouven; /Princeton, Inst. Advanced Study /YITP, Stony Brook /SLAC /Stanford U., Phys. Dept.; Hook, Anson; Torroba, Gonzalo; /SLAC /Stanford U., Phys. Dept.

2012-02-17T23:59:59.000Z

376

Mapping the Flip Angle in Magnetic Resonance Imaging Using the Accelerated 3D Look-Locker Sequence.  

E-Print Network (OSTI)

??In the ongoing quest to extract more information from MRI images, there has arisen a need to rapidly map the flip angle. This has been (more)

Wade, Trevor P

2010-01-01T23:59:59.000Z

377

Superconducting phase qubits  

Science Conference Proceedings (OSTI)

Experimental progress is reviewed for superconducting phase qubit research at the University of California, Santa Barbara. The phase qubit has a potential advantage of scalability, based on the low impedance of the device and the ability to microfabricate ... Keywords: 03.65.Yz, 03.67.Lx, 85.25.Cp, Decoherence, Quantum computation, Qubits, Superconductivity

John M. Martinis

2009-06-01T23:59:59.000Z

378

UPVG phase 2 report  

DOE Green Energy (OSTI)

The Utility PhotoVoltaic Group (UPVG), supported by member dues and a grant from the US Department of Energy, has as its mission the acceleration of the use of cost-effective small-scale and emerging large-scale applications of photovoltaics for the benefit of electric utilities and their customers. Formed in October, 1992, with the support of the American Public Power Association, Edison Electric Institute, and the National Rural Electric Cooperative Association, the UPVG currently has 90 members from all sectors of the electric utility industry. The UPVG`s efforts as conceived were divided into four phases: Phase 0--program plan; Phase 1--organization and strategy development; Phase 2--creating market assurance; and Phase 3--higher volume purchases. The Phase 0 effort developed the program plan and was completed early in 1993. The Phase 1 goal was to develop the necessary background information and analysis to lead to a decision as to which strategies could be undertaken by utilities to promote greater understanding of PV markets and achieve increased volumes of PV purchases. This report provides the details of the UPVG`s Phase 2 efforts to initiate TEAM-UP, its multiyear, 50-MW hardware initiative.

NONE

1995-08-01T23:59:59.000Z

379

Comment on 'Geometric phase of the gyromotion for charged particles in a time-dependent magnetic field'[Phys. Plasmas 18, 072505 (2011)  

Science Conference Proceedings (OSTI)

The geometric analysis of the gyromotion for charged particles in a time-dependent magnetic field by Liu and Qin [Phys. Plasmas 18, 072505 (2011)] is reformulated in terms of the spatial angles that represent the instantaneous orientation of the magnetic field. This new formulation, which includes the equation of motion for the pitch angle, clarifies the decomposition of the gyroangle-averaged equation of motion for the gyrophase into its dynamic and geometric contributions.

Brizard, Alain J. [Department of Physics, Saint Michael's College, Colchester, Vermont 05439 (United States); Guillebon, Loiec de [Centre de Physique Theorique Aix-Marseille Universite, CNRS (UMR 7332), 13288 Marseille Cedex 09 (France)

2012-09-15T23:59:59.000Z

380

Modelling the corrugation of the three-phase contact line perpendicular to a chemically striped substrate  

E-Print Network (OSTI)

We model an infinitely long liquid bridge confined between two plates chemically patterned by stripes of same width and different contact angle, where the three-phase contact line runs, on average, perpendicular to the stripes. This allows us to study the corrugation of a contact line in the absence of pinning. We find that, if the spacing between the plates is large compared to the length scale of the surface patterning, the cosine of the macroscopic contact angle corresponds to an average of cosines of the intrinsic angles of the stripes, as predicted by the Cassie equation. If, however, the spacing becomes of order the length scale of the pattern there is a sharp crossover to a regime where the macroscopic contact angle varies between the intrinsic contact angle of each stripe, as predicted by the local Young equation. The results are obtained using two numerical methods, Lattice Boltzmann (a diffuse interface approach) and Surface Evolver (a sharp interface approach), thus giving a direct comparison of two popular numerical approaches to calculating drop shapes when applied to a non-trivial contact line problem. We find that the two methods give consistent results if we take into account a line tension in the free energy. In the lattice Boltzmann approach, the line tension arises from discretisation effects at the diffuse three phase contact line.

F. J. Montes Ruiz-Cabello; H. Kusumaatmaja; M. A. Rodriguez-Valverde; J. M. Yeomans; M. A. Cabrerizo-Vilchez

2009-04-29T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

ARM - Measurement - Hydrometeor phase  

NLE Websites -- All DOE Office Websites (Extended Search)

phase phase ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hydrometeor phase Hydrometeor phase such as liquid ice or mixed phase Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Value-Added Products VISST : Minnis Cloud Products Using Visst Algorithm (Process) VISSTPX04G08V2MINNIS : VISST-derived pixel-level products from satellite GOES8, version 2 VISSTPX04G08V3MINNIS : VISST-derived pixel-level products from satellite GOES8, version 3

382

Langevin molecular dynamics derived from Ehrenfest dynamics  

E-Print Network (OSTI)

Stochastic Langevin molecular dynamics for nuclei is derived from quantum classical molecular dynamics, also called Ehrenfest dynamics, at positive temperature, assuming that the molecular bulk system is in equilibrium and that the initial data for the electrons is stochastically perturbed from the ground state. The initial electron probability distribution is derived from the Liouville equilibrium solution generated by the nuclei acting as a heat bath for the electrons. The diffusion and friction coefficients in the Langevin equation satisfy Einstein's fluctuation-dissipation relation. The fluctuating initial data yields, in addition to the fluctuating diffusion terms, also a contribution to the drift, modifying the standard ab initio Born-Oppenheimer solution at zero temperature, where the electrons are in their ground state for the current nuclear configuration. The dissipative friction mechanism comes from the evolution of the electron ground state, due to slow dynamics of the nuclei, while the modified d...

Szepessy, Anders

2007-01-01T23:59:59.000Z

383

AVESTAR® - Dynamic Modeling  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynamic Modeling Dynamic Modeling The AVESTAR team is pursuing research on the dynamic modeling and simulation of advanced energy systems ranging from power plants to power grids. Dynamic models provide a continuous view of energy systems in action by calculating their transient behavior over time. Plant-wide Models For power plants, dynamic models are used to analyze a wide variety of operating scenarios, including normal base load operation, startup, shutdown, feedstock switchovers, cycling, and load-following. Dynamic process and control models are also essential for analyzing plant responses to setpoint changes and disturbances, as well as malfunctions and abnormal situations. Other applications of plant-wide dynamic models include controllability and operational flexibility analyses, environmental studies, safety evaluations, and risk mitigation.

384

Petascale Adaptive Computational Fluid Dynamics | Argonne Leadership  

NLE Websites -- All DOE Office Websites (Extended Search)

Petascale Adaptive Computational Fluid Dynamics Petascale Adaptive Computational Fluid Dynamics PI Name: Kenneth Jansen PI Email: jansen@rpi.edu Institution: Rensselaer Polytechnic Institute The specific aim of this request for resources is to examine scalability and robustness of our code on BG/P. We have confirmed that, during the flow solve phase, our CFD flow solver does exhibit perfect strong scaling to the full 32k cores on our local machine (CCNI-BG/L at RPI) but this will be our first access to BG/P. We are also eager to study the performance of the adaptive phase of our code. Some aspects have scaled well on BG/L (e.g., refinement has produced adaptive meshes that take a 17 million element mesh and perform local adaptivity on 16k cores to match a requested size field to produce a mesh exceeding 1 billion elements) but other aspects (e.g.,

385

Measurement of specimen dimensions and dynamic pressure in dynamic triaxial experiments  

SciTech Connect

Novel experimental techniques are developed to measure the rapid changes in specimen dimensions during dynamic triaxial experiments. A capacitance gage is designed and constructed to measure the diameter change of the specimen inside the pressure chamber at both low and high rates. The length change is determined by a linear variable differential transformer at low rates and by Kolsky bar signals at high rates. The Kolsky bar also measures the dynamic axial stress in the specimen during the high-rate phase of an experiment. A line pressure gage records the hydrostatic pressure in the chamber. The dynamic pressure variation in the chamber during axial impact loading is detected by a manganin gage placed inside the chamber. The feasibility of this new experimental setup is demonstrated by dynamic triaxial experiments on a fine dry sand.

Kabir, Md. E. [School of Aeronautics/Astronautics, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907-2045 (United States); Chen, Weinong W. [School of Aeronautics/Astronautics, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907-2045 (United States); School of Materials Engineering, Purdue University, 701 West Stadium Avenue, West Lafayette, Indiana 47907-2045 (United States)

2009-12-15T23:59:59.000Z

386

Pressure drop of two-phase dry-plug flow in round mini-channels: Effect of moving contact line  

SciTech Connect

In the present experimental study, the pressure drop of the two-phase dry-plug flow (dry wall condition at the gas portions) in round mini-channels was investigated. The air-water mixtures were flowed through the round mini-channels made of polyurethane and Teflon, respectively, with their inner diameters ranging from 1.62 to 2.16 mm. In the dry-plug flow regime, the pressure drop measured became larger either by increasing the liquid superficial velocity or by decreasing the gas superficial velocity due to the increase of the number of the moving contact lines in the test section. In such a case, the role of the moving contact lines turned out to be significant. Therefore, a pressure drop model of dry-plug flow was proposed through modification of the dynamic contact angle analysis taking account of the energy dissipation by the moving contact lines, which represents the experimental data within the mean deviation of 4%. (author)

Lee, Chi Young; Lee, Sang Yong [Department of Mechanical Engineering, KAIST, Science Town, Daejeon 305-701 (Korea)

2010-01-15T23:59:59.000Z

387

Gas Phase Chemical Physics | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Gas Phase Chemical Physics Gas Phase Chemical Physics Chemical Sciences, Geosciences, & Biosciences (CSGB) Division CSGB Home About Research Areas Energy Frontier Research Centers (EFRCs) DOE Energy Innovation Hubs Scientific Highlights Reports & Activities Principal Investigators' Meetings BES Home Research Areas Gas Phase Chemical Physics Print Text Size: A A A RSS Feeds FeedbackShare Page Gas Phase Chemical Physics (GPCP) research emphasizes studies of the dynamics and rates of chemical reactions at energies characteristic of combustion, and the chemical and physical properties of key combustion intermediates. The overall aim is the development of a fundamental understanding of chemical reactivity enabling validated theories, models and computational tools for predicting rates, products, and dynamics of

388

Orientational Ordering and Dynamics of Rodlike Polyelectrolytes  

E-Print Network (OSTI)

The interplay between electrostatic interactions and orientational correlations is studied for a model system of charged rods positioned on a chain, using Monte Carlo simulation techniques. It is shown that the coupling brings about the notion of {\\em electrostatic frustration}, which in turn results in: (i) a rich variety of novel orientational orderings such as chiral phases, and (ii) an inherently slow dynamics characterized by stretched-exponential behavior in the relaxation functions of the system.

Hossein Fazli; Ramin Golestanian; Mohammad R. Kolahchi

2007-01-11T23:59:59.000Z

389

Maxwell rigidity and topological constraints in amorphous phase-change networks  

Science Conference Proceedings (OSTI)

By analyzing first-principles molecular-dynamics simulations of different telluride amorphous networks, we develop a method for the enumeration of radial and angular topological constraints, and show that the phase diagram of the most popular system Ge-Sb-Te can be split into two compositional elastic phases: a tellurium rich flexible phase and a stressed rigid phase that contains most of the materials used in phase-change applications. This sound atomic scale insight should open new avenues for the understanding of phase-change materials and other complex amorphous materials from the viewpoint of rigidity.

Micoulaut, M. [Laboratoire de Physique Theorique de la Matiere Condensee, Universite Pierre et Marie Curie, Boite 121, CNRS UMR 7600, 4 place Jussieu, 75252 Paris Cedex 05 (France); Otjacques, C.; Raty, J.-Y. [Physique de la Matiere Condensee, B5, Universite de Liege, B4000 Sart-Tilman (Belgium); Bichara, C. [Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), CNRS and Aix-Marseille Universities, Campus de Luminy, Case 913, 13288 Marseille (France)

2011-12-12T23:59:59.000Z

390

Superionic to superionic phase change in water: consequences for the interiors of Uranus and Neptune  

E-Print Network (OSTI)

Using density functional molecular dynamics free energy calculations, we show that the body-centered-cubic phase of superionic ice previously believed to be the only phase is in fact thermodynamically unstable compared to a novel phase with oxygen positions in fcc lattice sites. The novel phase has a lower proton mobility than the bc phase and may exhibit a higher melting temperature. We predict a transition between the two phases at a pressure of 1 +/- 0.5 Mbar, with potential consequences for the interiors of ice giants such as Uranus and Neptune.

Wilson, Hugh F; Militzer, Burkhard

2012-01-01T23:59:59.000Z

391

Transient stability enhancement of electric power generating systems by 120-degree phase rotation  

DOE Patents (OSTI)

A method and system for enhancing the transient stability of an intertied three-phase electric power generating system. A set of power exporting generators (10) is connected to a set of power importing generators (20). When a transient cannot be controlled by conventional stability controls, and imminent loss of synchronism is detected (such as when the equivalent rotor angle difference between the two generator sets exceeds a predetermined value, such as 150 degrees), the intertie is disconnected by circuit breakers. Then a switch (30) having a 120-degree phase rotation, or a circuit breaker having a 120-degree phase rotation is placed in the intertie. The intertie is then reconnected. This results in a 120-degree reduction in the equivalent rotor angle difference between the two generator sets, making the system more stable and allowing more time for the conventional controls to stabilize the transient.

Cresap, Richard L. (Portland, OR); Taylor, Carson W. (Portland, OR); Kreipe, Michael J. (Portland, OR)

1982-01-01T23:59:59.000Z

392

Inhomogeneous chiral symmetry breaking phases  

Science Conference Proceedings (OSTI)

We investigate inhomogeneous chiral symmetry breaking phases in the phase diagram of the two-flavor Nambu-Jona-Lasinio model, concentrating on phases with one-dimensional modulations. It is found that the first-order transition line in the phase diagram of homogeneous phases gets completely covered by an inhomogeneous phase which is bordered by second-order transition lines. The inhomogeneous phase turns out to be remarkably stable when vector interactions are included.

Buballa, M., E-mail: michael.buballa@physik.tu-darmstadt.de; Carignano, S., E-mail: carignano@crunch.ikp.physik.tu-darmstadt.de [Technische Universitaet Darmstadt, Institut fuer Kernphysik (Germany); Nickel, D., E-mail: mdjn@u.washington.edu [University of Washington, Institute for Nuclear Theory (United States)

2012-06-15T23:59:59.000Z

393

Multifunction Phased-Array Radar: Time Balance Scheduler for Adaptive Weather Sensing  

Science Conference Proceedings (OSTI)

Phased-array radars (PARs) have the capability of instantaneously and dynamically controlling beam position on a pulse-by-pulse basis, which allows a single radar to perform multiple functions, such as tracking multiple storms or weather and ...

Ricardo Reinoso-Rondinel; Tian-You Yu; Sebastin Torres

2010-11-01T23:59:59.000Z

394

Topological and Dynamical Complexity of Random Neural Networks  

E-Print Network (OSTI)

Random neural networks are dynamical descriptions of randomly interconnected neural units. These show a phase transition to chaos as a disorder parameter is increased. The microscopic mechanisms underlying this phase transition are unknown, and similarly to spin-glasses, shall be fundamentally related to the behavior of the system. In this Letter we investigate the explosion of complexity arising near that phase transition. We show that the mean number of equilibria undergoes a sharp transition from one equilibrium to a very large number scaling exponentially with the dimension on the system. Near criticality, we compute the exponential rate of divergence, called topological complexity. Strikingly, we show that it behaves exactly as the maximal Lyapunov exponent, a classical measure of dynamical complexity. This relationship unravels a microscopic mechanism leading to chaos which we further demonstrate on a simpler class of disordered systems, suggesting a deep and underexplored link between topological and dynamical complexity.

Gilles Wainrib; Jonathan Touboul

2012-10-18T23:59:59.000Z

395

Critique of the solid angle method. Technical report 1 Jul 75-30 Sep 77  

SciTech Connect

The solid angle method provides an approximation for nuclear criticality safety analyses for fissile arrays. It was formulated for use with highly-enriched systems. This study was initiated to determine applicability of this method to low-enriched uranium systems, using as a standard for comparison analyses the KENO-IV code and the Hansen-Roach cross sections. The report identified many conditions for which a margin of safety does exist, using the solid angle method. The study also determined that some applications exist for which a safety margin does not exist, using common criteria, and has recommended additional criteria needed to assure safety margins. These additional criteria have not been tested extensively to assure generic applicability.

Oden, D.R.; Thompson, J.K.; Lewallen, M.A.; Trapp, T.J.

1978-02-01T23:59:59.000Z

396

Elevation angle alignment of quasi optical receiver mirrors of collective Thomson scattering diagnostic by sawtooth measurements  

Science Conference Proceedings (OSTI)

Localized measurements of the fast ion velocity distribution function and the plasma composition measurements are of significant interest for the fusion community. Collective Thomson scattering (CTS) diagnostics allow such measurements with spatial and temporal resolution. Localized measurements require a good alignment of the optical path in the transmission line. Monitoring the alignment during the experiment greatly benefits the confidence in the CTS measurements. An in situ technique for the assessment of the elevation angle alignment of the receiver is developed. Using the CTS diagnostic on TEXTOR without a source of probing radiation in discharges with sawtooth oscillations, an elevation angle misalignment of 0.9 Degree-Sign was found with an accuracy of 0.25 Degree-Sign .

Moseev, D. [FOM DIFFER - Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Nieuwegein (Netherlands); Max-Planck-Institut fuer Plasmaphysik, Euratom Association-IPP, 85748 Garching (Germany); Meo, F.; Korsholm, S. B.; Leipold, F.; Michelsen, P. K.; Nielsen, S. K.; Salewski, M.; Stejner, M. [Association EURATOM - DTU, Department of Physics, Technical University of Denmark, Riso Campus, 4000 Roskilde (Denmark); Bindslev, H. [Faculty of Science and Technology, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Furtula, V. [Chalmers University of Technology, SE-412 96 Gothenburg (Sweden); Kantor, M. [FOM DIFFER - Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Nieuwegein (Netherlands); FZ Juelich GmbH, EURATOM, Trilateral Euregio Cluster, D-52425 Juelich (Germany); Ioffe Institute, RAS, Saint Petersburg 194021 (Russian Federation)

2012-10-15T23:59:59.000Z

397

Cerenkov angle and charge reconstruction with the RICH detector of the AMS experiment  

E-Print Network (OSTI)

The Alpha Magnetic Spectrometer (AMS) experiment to be installed on the International Space Station (ISS) will be equipped with a proximity focusing Ring Imaging Cerenkov (RICH) detector, for measurements of particle electric charge and velocity. In this note, two possible methods for reconstructing the Cerenkov angle and the electric charge with the RICH, are discussed. A Likelihood method for the Cerenkov angle reconstruction was applied leading to a velocity determination for protons with a resolution of around 0.1%. The existence of a large fraction of background photons which can vary from event to event, implied a charge reconstruction method based on an overall efficiency estimation on an event-by-event basis.

F. Barao; L. Arruda; J. Borges; P. Goncalves; M. Pimenta; I. Perez

2002-10-18T23:59:59.000Z

398

Note: Grazing incidence small and wide angle x-ray scattering combined with imaging ellipsometry  

SciTech Connect

The combination of grazing incidence small angle x-ray scattering (GISAXS) and grazing incidence wide angle x-ray scattering (GIWAXS) with optical imaging ellipsometry is presented as an upgrade of the available measurement techniques at the wiggler beamline BW4 of the Hamburger Synchrotronstrahlungslabor. The instrument is introduced with the description of the alignment procedure to assure the measurement of imaging ellipsometry and GISAXS/GIWAXS on the same sample spot. To demonstrate the possibilities of the new instrument examples of morphological investigation on films made of poly(3-hexylthiophene) and [6,6]-phenyl-C{sub 61} butyric acid methyl ester as well as textured poly(9,9-dioctylfluorene-alt-benzo-thia-diazole) are shown.

Koerstgens, V.; Meier, R.; Ruderer, M. A.; Guo, S.; Chiang, H.-Y.; Mueller-Buschbaum, P. [Technische Universitaet Muenchen, Physik-Department, Lehrstuhl fuer Funktionelle Materialien, James-Franck-Str. 1, 85748 Garching (Germany); Perlich, J.; Roth, S. V.; Gehrke, R. [HASYLAB, DESY, Notkestr. 85, 22607, Hamburg (Germany)

2012-07-15T23:59:59.000Z

399

BIOISIS: Biological Macromolecules by Small Angle X-ray Scattering (SAXS)  

DOE Data Explorer (OSTI)

BIOISIS is an open access database dedicated to the study of biological macromolecules by small angle X-ray scattering (SAXS). BIOISIS aims to become the complete source for the deposition, distribution and maintenance of small angle X-ray scattering data and technologies. The database is designed around the concept of an experiment and relates a specific experiment to a set of genes, organisms, computational models and experimental data. As of May 2012, BIOSIS contains 7,118 genes covering four different organisms. Forty-two modeled structures are available. Clicking on a structures reveals scattering curves, experimental conditions, and experimental values. The data are collected at Beamline 12.3.1 of the Advanced Light Source (ALS).[Copied with editing from http://www.bioisis.net/about

Tainer, John (Scripps Research Institute); Hura, Greg (LBNL); Rambo, Robert P. (LBNL)

400

Beam power and angle adaptation in multibeam 2.5 Gbit/s spot diffusing mobile optical wireless system  

Science Conference Proceedings (OSTI)

Mobility can induce significant signal-to-noise ratio (SNR) performance degradation in optical wireless (OW) systems based on diffuse as well as spot-diffusing configurations. Two methods (beam angle and beam power adaptation) are introduced to the design ... Keywords: beam angle adaptation, diversity receiver, optical wireless communication, transmit power adaptation

Fuad E. Alsaadi; Jaafar M. H. Elmirghani

2010-08-01T23:59:59.000Z

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401

Research article: Monte Carlo-based rigid body modelling of large protein complexes against small angle scattering data  

Science Conference Proceedings (OSTI)

We present a modular, collaborative, open-source architecture for rigid body modelling based upon small angle scattering data, named sas_rigid. It is designed to provide a fast and extensible scripting interface using the easy-to-learn Python programming ... Keywords: Hemocyanin, Monte Carlo with simulated annealing, Rigid body modelling, Small angle scattering (SAS)

Christian Meesters; Bruno Pairet; Anja Rabenhorst; Heinz Decker; Elmar Jaenicke

2010-06-01T23:59:59.000Z

402

Double Chooz, A Search for the Neutrino Mixing Angle theta-13  

E-Print Network (OSTI)

The Double Chooz Reactor Neutrino Experiment in France plans to quickly measure the neutrino mixing angle theta-13, or limit it to sin^2 2-theta_13 less than 0.025. The physics reach, experimental site, detector structures, scintillator, photodetection, electronics, calibration and simulations are described. The possibility of using Double Chooz to explore the possible use of a antineutrino detector for non-proliferation goals is also presented.

Lasserre, T

2006-01-01T23:59:59.000Z

403

Study of High Temperature Superconductors with Angle-Resolved Photoemission Spectroscopy  

Science Conference Proceedings (OSTI)

The Angle Resolved Photoemission Spectroscopy (ARPES) recently emerged as a powerful tool for the study of highly correlated materials. This thesis describes the new generation of ARPES experiment, based on the third generation synchrotron radiation source and utilizing very high resolution electron energy and momentum analyzer. This new setup is used to study the physics of high temperature superconductors. New results on the Fermi surfaces, dispersions, scattering rate and superconducting gap in high temperature superconductors are presented.

Dunn, Lisa

2003-05-13T23:59:59.000Z

404

High-harmonic XUV source for time- and angle-resolved photoemission spectroscopy  

Science Conference Proceedings (OSTI)

We present a laser-based apparatus for visible pump/XUV probe time- and angle-resolved photoemission spectroscopy (TRARPES) utilizing high-harmonic generation from a noble gas. Femtosecond temporal resolution for each selected harmonic is achieved by using a time-delay-compensated monochromator (TCM). The source has been used to obtain photoemission spectra from insulators (UO{sub 2}) and ultrafast pump/probe processes in semiconductors (GaAs).

Dakovski, Georgi L [Los Alamos National Laboratory; Li, Yinwan [Los Alamos National Laboratory; Durakiewicz, Tomasz [Los Alamos National Laboratory; Rodriguez, George [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

405

Leptonic CP Phase in {nu}{sub {mu}}{yields}{nu}{sub {mu}} Oscillations  

Science Conference Proceedings (OSTI)

In the case of large 1-3 mixing angle as sin{sup 2} 2{theta}{sub 13}{>=}0.03, we investigate the possibility for measuring the leptonic CP phase by using only {nu}{sub {mu}}{yields}{nu}{sub {mu}} oscillations independently of {nu}{sub {mu}}{yields}{nu}{sub e} oscillations. As the result, we find that the CP phase can be measured best around the energy E = 0.43 GeV and the baseline length L = 5000 km without depending on the uncertainties of other parameters too much. In this region, the CP phase effect remains even after averaging over neutrino energy.

Kimura, Keiichi; Yoshikawa, Tadashi [Department of Physics, Nagoya University, Nagoya, 464-8602 (Japan); Takamura, Akira [Department of Mathematics, Toyota National College of Technology Eisei-cho 2-1, Toyota-shi, 471-8525 (Japan)

2008-02-21T23:59:59.000Z

406

Faster Phase Estimation  

E-Print Network (OSTI)

We develop several algorithms for performing quantum phase estimation based on basic measurements and classical post-processing. We present a pedagogical review of quantum phase estimation and simulate the algorithm to numerically determine its scaling in circuit depth and width. We show that the use of purely random measurements requires a number of measurements that is optimal up to constant factors, albeit at the cost of exponential classical post-processing; the method can also be used to improve classical signal processing. We then develop a quantum algorithm for phase estimation that yields an asymptotic improvement in runtime, coming within a factor of log* of the minimum number of measurements required while still requiring only minimal classical post-processing. The corresponding quantum circuit requires asymptotically lower depth and width (number of qubits) than quantum phase estimation.

Krysta M. Svore; Matthew B. Hastings; Michael Freedman

2013-04-02T23:59:59.000Z

407

Chemical Structure and Dynamics  

NLE Websites -- All DOE Office Websites (Extended Search)

2154-3 2154-3 UC-400 Annual Report 2000 Chemical Structure and Dynamics Steven D. Colson, Associate Director Robin S. McDowell, Program Manager and the Staff of the Chemical Structure and Dynamics Program April 2001 Prepared for the U.S. Department of Energy under Contract DE-AC06-76RL01830 Chemical Structure and Dynamics 2000 Annual Report Contents Chemical Structure and Dynamics 2000 Annual Report Chemical Structure and Dynamics 2000 Annual Report 1. Introduction Chemical Structure and Dynamics Program......................................................... 1-3 2. Reaction Mechanisms at Liquid Interfaces Structure and Reactivity of Ice Surfaces and Interfaces G. A. Kimmel, Z. Dohnálek, K. P. Stevenson, R. S. Smith,

408

The General-Purpose Small-Angle Neutron Scattering Diffractometer at HFIR -  

NLE Websites -- All DOE Office Websites (Extended Search)

General-Purpose Small-Angle Neutron Scattering Diffractometer at HFIR General-Purpose Small-Angle Neutron Scattering Diffractometer at HFIR Instrument scientist Ken Littrell at GP-SANS. Instrument scientist Ken Littrell at GP-SANS. The General-Purpose Small-Angle Neutron Scattering Diffractometer (GP-SANS) instrument is optimized for providing information about structure and interactions in materials in the size range of 0.5 - 200 nm. It has a cold neutron flux on sample and capabilities comparable to those of the best SANS instruments worldwide, including a wide range of neutron wavelengths λ 5 - 30 Å, resolution Δλ ⁄ λ 9=45%, and a 1m2 area detector with 5 × 5mm2 pixel resolution with a maximum counting capability of up to 2.5 kHz. The sample-to-detector distance can be varied from 1 to 20 m, and the detector can be offset horizontally by up to 45 cm, allowing

409

Experimental and computational studies of film cooling with compound angle injection  

DOE Green Energy (OSTI)

The thermal efficiency of gas turbine systems depends largely on the turbine inlet temperature. Recent decades have seen a steady rise in the inlet temperature and a resulting reduction in fuel consumption. At the same time, it has been necessary to employ intensive cooling of the hot components. Among various cooling methods, film cooling has become a standard method for cooling of the turbine airfoils and combustion chamber walls. The University of Minnesota program is a combined experimental and computational study of various film-cooling configurations. Whereas a large number of parameters influence film cooling processes, this research focuses on compound angle injection through a single row and through two rows of holes. Later work will investigate the values of contoured hole designs. An appreciation of the advantages of compound angle injection has risen recently with the demand for more effective cooling and with improved understanding of the flow; this project should continue to further this understanding. Approaches being applied include: (1) a new measurement system that extends the mass/heat transfer analogy to obtain both local film cooling and local mass (heat) transfer results in a single system, (2) direct measurement of three-dimensional turbulent transport in a highly-disturbed flow, (3) the use of compound angle and shaped holes to optimize film cooling performance, and (4) an exploration of anisotropy corrections to turbulence modeling of film cooling jets.

Goldstein, R.J.; Eckert, E.R.G.; Patankar, S.V.; Simon, T.W. [Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Mechanical Engineering

1995-12-31T23:59:59.000Z

410

The performance of the small-angle diffractometer, SAND at IPNS.  

Science Conference Proceedings (OSTI)

The time-of-flight small-angle diffractometer SAND has been serving the scientific user community since 1996. One notable feature of SAND is its capability to measure the scattered intensity in a wide Q (4{pi}sin{theta}/{lambda}, where 2{theta} is the scattering angle and {lambda} is the wavelength of the neutrons) range of 0.0035 to 0.5 {angstrom}{sup {minus}1} in a single measurement. The optical alignment system makes it easy to set up the instrument and the sample. The cryogenically cooled MgO filter reduces the fast neutrons over two orders of magnitude, while still transmitting over 70% of the cold neutrons. A drum chopper running at 15 Hz suppresses the delayed neutron background. SAND has a variety of ancillary equipment to control the sample environment. In this paper we describe the features of the SAND instrument, compare its data on a few standard samples with those measured at well established centers in the world, and display two scientific examples which take advantage of measuring data in a wide Q-range in a single measurement. With a new set of tight collimators the Q{sub min} can be lowered to 0.002 {angstrom}{sup {minus}1} and the presently installed high-angle bank of detectors will extend the Q{sub max} to 2 {angstrom}{sup {minus}1}.

Thiyagarajan, P.

1998-07-17T23:59:59.000Z

411

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells Multiple Hydraulic Fractures  

SciTech Connect

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. A high-angle well will be drilled in the fan-margin portion of a slope-basin clastic reservoir and will be completed with multiple hydraulic-fracture treatments. Geologic modeling, reservoir characterization, and fine-grid reservoir simulation will be used to select the well location and orientation. Design parameters for the hydraulic-fracture treatments will be determined, in part, by fracturing an existing test well. Fracture azimuth will be predicted by passive seismic monitoring of a fracture-stimulation treatment in the test well using logging tools in an offset well.

Mike L. Laue

1997-10-30T23:59:59.000Z

412

Magnetic field pitch angle diagnostic using the motional Stark effect (invited)  

DOE Green Energy (OSTI)

The Stark effect has been employed in a novel technique for obtaining the pitch angle profile and {ital q}({ital r}) using polarimetry measurements of the Doppler shifted {ital H}{sub {alpha}} emission from a hydrogen diagnostic neutral beam. As a neutral beam propagates through a plasma, collisions of the beam particles with the background ions and electrons will excite beam atoms, leading to emission of radiation. The motional Stark effect, which arises from the electric field induced in the atom's rest frame due to the beam motion across the magnetic field ({bold E}={bold V}{sub beam}{times}{bold B}), causes a wavelength splitting of several angstroms and polarization of the emitted radiation. The {Delta}{ital m}={plus minus}1 transitions, or {sigma} components, from the beam fluorescence are linearly polarized parallel to the direction of the local magnetic field when viewed transverse to the fields. Since the hydrogen beam provides good spatial localization and penetration, the pitch angle can be obtained anywhere in the plasma. A photoelastic modulator (PEM) is used to modulate the linearly polarized light. Depending on the orientation of the PEM, it can measure the sine or cosine of the angle of polarization. Two PEM's are used to measure both components simultaneously. Results of {ital q}({ital r}) for both Ohmic and NBI heated discharges have been obtained in the Princeton Beta Experiment (PBX-M) tokamak, with an uncertainty of {approximately}6% for {ital q}(0).

Levinton, F.M. (Fusion Physics Technology, Torrance, CA (USA)); Gammel, G.M.; Kaita, R.; Kugel, H.W.; Roberts, D.W. (Princeton Plasma Physics Laboratory, Princeton, NJ (USA))

1990-10-01T23:59:59.000Z

413

ECONOMIC RECOVERY OF OIL TRAPPED AT FAN MARGINS USING HIGH ANGLE WELLS AND MULTIPLE HYDRAULIC FRACTURES  

Science Conference Proceedings (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. A high-angle well will be drilled in the fan-margin portion of a slope-basin clastic reservoir and will be completed with multiple hydraulic-fracture treatments. Geologic modeling, reservoir characterization, and fine-grid reservoir simulation will be used to select the well location and orientation. Design parameters for the hydraulic-fracture treatments will be determined, in part, by fracturing an existing test well. Fracture azimuth will be predicted by passive seismic monitoring of a fracture-stimulation treatment in the test well using logging tools in an offset well.

Mike L. Laue

1998-11-06T23:59:59.000Z

414

Complexity-based program phase analysis and classification  

Science Conference Proceedings (OSTI)

Modeling and analysis of program behavior are at the foundation of computer system design and optimization. As computer systems become more adaptive, their efficiency increasingly depends on program dynamic characteristics. Previous studies have revealed ... Keywords: computer architecture, performance modeling, program phase, wavelet

Chang-Burm Cho; Tao Li

2006-09-01T23:59:59.000Z

415

Understanding reservoir mechanisms using phase and component streamline tracing  

E-Print Network (OSTI)

Conventionally streamlines are traced using total flux across the grid cell faces. The visualization of total flux streamlines shows the movement of flood, injector-producer relationship, swept area and movement of tracer. But they fail to capture some important signatures of reservoir dynamics, such as dominant phase in flow, appearance and disappearance of phases (e.g. gas), and flow of components like CO2. In the work being presented, we demonstrate the benefits of visualizing phase and component streamlines which are traced using phase and component fluxes respectively. Although the phase and component streamlines are not appropriate for simulation, as they might be discontinuous, they definitely have a lot of useful information about the reservoir processes and recovery mechanisms. In this research, phase and component streamline tracing has been successfully implemented in three-phase and compositional simulation and the additional information obtained using these streamlines have been explored. The power and utility of the phase and component streamlines have been demonstrated using synthetic examples and two field cases. The new formulation of streamline tracing provides additional information about the reservoir drive mechanisms. The phase streamlines capture the dominant phase in flow in different parts of the reservoir and the area swept corresponding to different phases can be identified. Based on these streamlines the appearance and disappearance of phases can be identified. Also these streamlines can be used for optimizing the field recovery processes like water injection and location of infill wells. Using component streamlines the movement of components like CO2 can be traced, so they can be used for optimizing tertiary recovery mechanisms and tracking of tracers. They can also be used to trace CO2 in CO2 sequestration project where the CO2 injection is for long term storage in aquifers or reservoirs. They have also other potential uses towards study of reservoir processes and behavior such as drainage area mapping for different phases, phase rate allocations to reservoir layers, etc.

Kumar, Sarwesh

2008-08-01T23:59:59.000Z

416

Efficiency of the dynamical mechanism  

E-Print Network (OSTI)

The most extreme starbursts occur in galaxy mergers, and it is now acknowledged that dynamical triggering has a primary importance in star formation. This triggering is due partly to the enhanced velocity dispersion provided by gravitational instabilities, such as density waves and bars, but mainly to the radial gas flows they drive, allowing large amounts of gas to condense towards nuclear regions in a small time scale. Numerical simulations with several gas phases, taking into account the feedback to regulate star formation, have explored the various processes, using recipes like the Schmidt law, moderated by the gas instability criterion. May be the most fundamental parameter in starbursts is the availability of gas: this sheds light on the amount of external gas accretion in galaxy evolution. The detailed mechanisms governing gas infall in the inner parts of galaxy disks are discussed.

F. Combes

2004-11-15T23:59:59.000Z

417

Qualification of a computer program for drill string dynamics  

DOE Green Energy (OSTI)

A four point plan for the qualification of the GEODYN drill string dynamics computer program is described. The qualification plan investigates both modal response and transient response of a short drill string subjected to simulated cutting loads applied through a polycrystalline diamond compact (PDC) bit. The experimentally based qualification shows that the analytical techniques included in Phase 1 GEODYN correctly simulate the dynamic response of the bit-drill string system. 6 refs., 8 figs.

Stone, C.M.; Carne, T.G.; Caskey, B.C.

1985-01-01T23:59:59.000Z

418

The application of taylor weighting, digital phase shifters, and digital attenuators to phased-array antennas.  

SciTech Connect

Application of Taylor weighting (taper) to an antenna aperture can achieve low peak sidelobes, but combining the Taylor weighting with quantized attenuators and phase shifters at each radiating element will impact the performance of a phased-array antenna. An examination of array performance is undertaken from the simple point of view of the characteristics of the array factor. Design rules and guidelines for determining the Taylor-weighting parameters, the number of bits required for the digital phase shifter, and the dynamic range and number of bits required for the digital attenuator are developed. For a radar application, when each element is fed directly from a transmit/receive module, the total power radiated by the array will be reduced as a result of the taper. Consequently, the issue of whether to apply the taper on both transmit and receive configurations, or only on the receive configuration is examined with respect to two-way sidelobe performance.

Brock, Billy C.

2008-03-01T23:59:59.000Z

419

Dynamic Instruction Fusion  

E-Print Network (OSTI)

SANTA CRUZ DYNAMIC INSTRUCTION FUSION A thesis submitted in4 2.2 Instruction Fusion & Complex10 3.1 Fusion Selection

Lee, Ian

2012-01-01T23:59:59.000Z

420

Fundamentals of Dynamic Behavior  

Science Conference Proceedings (OSTI)

Feb 28, 2011 ... Atomistically-Informed Dislocation Dynamics Simulations of High Rate Deformation of Single fcc Crystals: Zhiqiang Wang1; 1University of North...

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Dynamic Windows.pdf  

NLE Websites -- All DOE Office Websites (Extended Search)

including products with improved fixed or static properties and products with dynamic solar heat gain proper- ties. Nine representative window products are examined in eight...

422

Electro-optic Phase Grating Streak Spectrometer  

SciTech Connect

The electro-optic phase grating streak spectrometer (EOPGSS) generates a time-resolved spectra equivalent to that obtained with a conventional spectrometer/streak camera combination, but without using a streak camera (by far the more expensive and problematic component of the conventional system). The EOPGSS is based on a phase, rather than an amplitude grating. Further, this grating is fabricated of electro-optic material such as, for example, KD*P, by either etching grooves into an E-O slab, or by depositing lines of the E-O material onto an optical flat. An electric field normal to the grating alters the materials index of refraction and thus affects a shift (in angle) of the output spectrum. Ramping the voltage streaks the spectrum correspondingly. The streak and dispersion directions are the same, so a second (static, conventional) grating disperses the spectrum in the orthogonal direction to prevent different wavelengths from overwriting each other. Because the streaking is done by the grating, the streaked output spectrum is recorded with a time-integrating device, such as a CCD. System model, typical design, and performance expectations will be presented.

Goldin, F. J.

2012-08-02T23:59:59.000Z

423

The effects of diamond injector angles on flow structures at various Mach numbers  

E-Print Network (OSTI)

Numerical simulations of a three dimensional diamond jet interaction flowfield at various diamond injector half angles into a supersonic crossflow were presented in this thesis. The numerical study was performed to improve the understanding of the flame holding potential by extending the numerical database envelop to include different injector half angles and examine the flow at Mach 2 and Mach 5. The configuration of a diamond injector shape was found to reduce the flow separation upstream, and produce an attached shock at the initial freestream interaction and the injection fluid has an increased field penetration as compared to circular injectors. The CFD studies were also aimed at providing additional information on the uses of multiple injectors for flow control. The numerical runs were performed with diamond injectors at half angles of 10?° and 20?° at a freestream Mach number of 5. The transverse counter-rotating pair of vortices found in the 15?° does not form within the 10?° and 20?° cases at freestream Mach number 5. The 10?° case had a barrel shock that became streamlined in the lateral direction. The 20?° barrel shock had a very large spanwise expansion and became streamlined in the transverse direction. In both cases the trailing edge of their barrel shocks did not form the flat â??Vâ? shape, as found in the baseline case. At Mach 2 the 10?° and 15?° cases both formed the flat â??Vâ? shape at the trailing edge of the barrel shocks, and formed the transverse counter rotating vortex pairs. The 10?° multiple injector case successfully showed the interaction shocks forming into a larger planer shock downstream of the injectors. The swept 15?° case produced interaction shocks that were too weak to properly form a planar shock downstream. This planar shock has potential for flow control. Depending on the angle of incidence of the injector fluid with the freestream flow and the half angle of the diamond injector, the planar shocks will form further upstream or downstream of the injector.

McLellan, Justin Walter

2005-08-01T23:59:59.000Z

424

Dynamic ray tracing and traveltime corrections for global seismic tomography  

Science Conference Proceedings (OSTI)

We present a dynamic ray tracing program for a spherically symmetric Earth that may be used to compute Frechet kernels for traveltime and amplitude anomalies at finite frequency. The program works for arbitrarily defined phases and background models. The numerical precisions of kinematic and dynamic ray tracing are optimized to produce traveltime errors under 0.1 s, which is well below the data uncertainty in global seismology. This tolerance level is obtained for an integration step size of about 20 km for the most common seismic phases. We also give software to compute ellipticity, crustal and topographic corrections and attenuation.

Tian Yue [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States)], E-mail: ytian@princeton.edu; Hung, S.-H. [Department of Geosciences, National Taiwan University, Taipei 106, Taiwan (China); Nolet, Guust [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States); Montelli, Raffaella [ExxonMobil Upstream Research Company, P.O. Box 22189, GW03-940A, Houston, TX 77252-2189 (United States); Dahlen, F.A. [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States)

2007-09-10T23:59:59.000Z

425

Dynamics of electrostatically driven granular media: Effects of humidity  

SciTech Connect

We performed experimental studies of the effect of humidity on the dynamics of electrostatically driven granular materials. Both conducting and dielectric particles undergo a phase transition from an immobile state (granular solid) to a fluidized state (granular gas) with increasing applied field. Spontaneous precipitation of solid clusters from the gas phase occurs as the external driving is decreased. The clustering dynamics in conducting particles is primarily controlled by screening of the electric field but is aided by cohesion due to humidity. It is shown that humidity effects dominate the clustering process with dielectric particles.

Howell, D. W.; Aronson, Igor S.; Crabtree, G. W.

2001-05-01T23:59:59.000Z

426

Molecular simulation of nano-dispersed fluid phases  

E-Print Network (OSTI)

Fluid phase equilibria involving nano-dispersed phases, where at least one of the coexisting phases is confined to a small volume, are investigated by molecular dynamics simulation. Complementing previous studies on nanoscopic droplets, simulation volumes containing a nanoscopic gas bubble surrounded by a subsaturated liquid phase under tension, i.e. at negative pressure, are conducted in the canonical ensemble. The boundary conditions are chosen such that the phase equilibrium at the curved interface is thermodynamically stable. Two distinct size-dependent effects are found: Curvature induces a subsaturation of the system, leading to a smaller liquid density. For the gas in the centre of the bubble, the small diameter has an additional obverse effect, increasing its density. The curvature dependence of the surface tension is discussed by evaluating average radial density profiles to obtain the excess equimolar radius, which is found to be positive, corresponding to a negative Tolman length.

Martin Horsch; Hans Hasse

2013-07-22T23:59:59.000Z

427

New Phases of Hydrogen-Bonded Systems at Extreme Conditions  

DOE Green Energy (OSTI)

We study the behavior of hydrogen-bonded systems under high-pressure and temperature. First principle calculations of formic acid under isotropic pressure up to 70 GPa reveal the existence of a polymerization phase at around 20 GPa, in support of recent IR, Raman, and XRD experiments. In this phase, covalent bonding develops between molecules of the same chain through symmetrization of hydrogen bonds. We also performed molecular dynamics simulations of water at pressures up to 115 GPa and 2000 K. Along this isotherm, we are able to define three different phases. We observe a molecular fluid phase with superionic diffusion of the hydrogens for pressure 34 GPa to 58 GPa. We report a transformation to a phase dominated by transient networks of symmetric O-H hydrogen bonds at 95-115 GPa. As in formic acid, the network can be attributed to the symmetrization of the hydrogen bond, similar to the ice VII to ice X transition.

Manaa, M R; Goldman, N; Fried, L E

2006-10-23T23:59:59.000Z

428

Thin Film Absorbers Based on Plasmonic Phase Resonances  

E-Print Network (OSTI)

We demonstrate an efficient double-layer light absorber by exciting plasmonic phase resonances. We show that the addition of grooves can cause mode splitting of the plasmonic waveguide cavity modes and all the new resonant modes exhibit large absorptivity greater than 90%. Some of the generated absorption peaks have wide-angle characteristics. Furthermore, we find that the proposed structure is fairly insensitive to the alignment error between different layers. The proposed plasmonic nano-structure designs may have exciting potential applications in thin film solar cells, thermal emitters, novel infrared detectors, and highly sensitive bio-sensors.

Cui, Yanxia; Xu, Jun; He, Sailing; Fang, Nicholas X

2010-01-01T23:59:59.000Z

429

Application of Small Angle Scattering to FeCo-based Soft Magnetic ...  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

430

Response to 'Comment on 'Geometric phase of the gyromotion for charged particles in a time-dependent magnetic field''[Phys. Plasmas 19, 094701 (2012)  

Science Conference Proceedings (OSTI)

The reformulation of our analysis on the geometric phase of the gyromotion [J. Liu and H. Qin, Phys. Plasmas 18, 072505 (2011)] in terms of spatial angles presented in the comment by Brizard and Guillebon is interesting and correct. The subtlety of whether the adiabatic term associated with the long term average of the variation of pitch angle completely disappears after the gyrophase average is related to where valid approximations are applied. But it has no impact on the main conclusions.

Liu Jian [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Qin Hong [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

2012-09-15T23:59:59.000Z

431

For Edison Phase 1 users  

NLE Websites -- All DOE Office Websites (Extended Search)

For Edison Phase 1 users For Edison Phase 1 users You can run jobs in the same way as you did on the phase 1 system, but keep in mind that the number of cores per node is 24...

432

Phase Resetting in an Asymptotically Phaseless System: On the Phase Response of Limit Cycles Verging on a Heteroclinic Orbit  

E-Print Network (OSTI)

Rhythmic behaviors in neural systems often combine features of limit cycle dynamics (stability and periodicity) with features of near heteroclinic or near homoclinic cycle dynamics (extended dwell times in localized regions of phase space). Proximity of a limit cycle to one or more saddle equilibria can have a profound effect on the timing of trajectory components and response to both fast and slow perturbations, providing a possible mechanism for adaptive control of rhythmic motions. Reyn showed that for a planar dynamical system with a stable heteroclinic cycle (or separatrix polygon), small perturbations satisfying a net inflow condition will generically give rise to a stable limit cycle (Reyn, 1980; Guckenheimer and Holmes, 1983). Here we consider the asymptotic behavior of the infinitesimal phase response curve (iPRC) for examples of two systems satisfying Reyn's inflow criterion, (i) a smooth system with a chain of four hyperbolic saddle points and (ii) a piecewise linear system corresponding to local l...

Shaw, Kendrick M; Thomas, Peter J

2011-01-01T23:59:59.000Z

433

Towards dynamic collaboration architectures  

Science Conference Proceedings (OSTI)

In this paper, we introduce the concept of dynamically changing between centralized, replicated, and hybrid collaboration architectures. It is implemented by providing users a function that dynamically changes the mapping between user-interface and program ... Keywords: ad-hoc collaboration, application sharing, collaboration architecture, latecomers, mobile collaboration

Goopeel Chung; Prasun Dewan

2004-11-01T23:59:59.000Z

434

Another View of Phase Diagrams  

Science Conference Proceedings (OSTI)

On 2D phase fraction charts these are lines where the fraction equals one. However another type of diagram can be drawn using lines where the phase fraction...

435

Langevin molecular dynamics derived from Ehrenfest dynamics  

E-Print Network (OSTI)

Stochastic Langevin molecular dynamics for nuclei is derived from the Ehrenfest Hamiltonian system (also called quantum classical molecular dynamics) in a Kac-Zwanzig setting, with the initial data for the electrons stochastically perturbed from the ground state and the ratio, $M$, of nuclei and electron mass tending to infinity. The Ehrenfest nuclei dynamics is approximated by the Langevin dynamics with accuracy $o(M^{-1/2})$ on bounded time intervals and by $o(1)$ on unbounded time intervals, which makes the small $\\mathcal{O}(M^{-1/2})$ friction and $o(M^{-1/2})$ diffusion terms visible. The initial electron probability distribution is a Gibbs density at low temperture, derived by a stability and consistency argument: starting with any equilibrium measure of the Ehrenfest Hamiltonian system, the initial electron distribution is sampled from the equilibrium measure conditioned on the nuclei positions, which after long time leads to the nuclei positions in a Gibbs distribution (i.e. asymptotic stability); by consistency the original equilibrium measure is then a Gibbs measure.The diffusion and friction coefficients in the Langevin equation satisfy the Einstein's fluctuation-dissipation relation.

Anders Szepessy

2007-12-21T23:59:59.000Z

436

RAYLEIGH-TAYLOR STRENGTH EXPERIMENTS OF THE PRESSURE-INDUCED alpha->epsilon->alpha' PHASE TRANSITION IN IRON  

SciTech Connect

We present here the first dynamic Rayleigh-Taylor (RT) strength measurement of a material undergoing solid-solid phase transition. Iron is quasi-isentropically driven across the pressure-induced bcc ({alpha}-Fe) {yields} hcp ({var_epsilon}-Fe) phase transition and the dynamic strength of the {alpha}, {var_epsilon} and reverted {alpha}{prime} phases have been determined via proton radiography of the resulting Rayleigh-Taylor unstable interface between the iron target and high-explosive products. Simultaneous velocimetry measurements of the iron free surface yield the phase transition dynamics and, in conjunction with detailed hydrodynamic simulations, allow for determination of the strength of the distinct phases of iron. Forward analysis of the experiment via hydrodynamic simulations reveals significant strength enhancement of the dynamically-generated {var_epsilon}-Fe and reverted {alpha}{prime}-Fe, comparable in magnitude to the strength of austenitic stainless steels.

Belof, J L; Cavallo, R M; Olson, R T; King, R S; Gray, G T; Holtkamp, D B; Chen, S R; Rudd, R E; Barton, N R; Arsenlis, A; Remington, B A; Park, H; Prisbrey, S T; Vitello, P A; Bazan, G; Mikaelian, K O; Comley, A J; Maddox, B R; May, M J

2011-08-10T23:59:59.000Z

437

Dielectric barrier plasma dynamics for active control of separated flows  

Science Conference Proceedings (OSTI)

The dynamics of separation mitigation with asymmetric dielectric barrier discharges is explored by considering the gas flow past a flat plate at an angle of attack. A self-consistent model utilizing motion of electrons, ions, and neutrals is employed to couple the electric force field to the momentum of the fluid. The charge separation and concomitant electric field yield a time-averaged body force which is oriented predominantly downstream, with a smaller transverse component towards the wall. This induces a wall-jet-like feature that effectively eliminates the separation bubble. The impact of several geometric and electrical operating parameters is elucidated.

Roy, Subrata; Singh, K.P.; Gaitonde, Datta V. [Computational Plasma Dynamics Laboratory, Mechanical Engineering, Kettering University, Flint, Michigan 48504 (United States); Computational Sciences Branch, Air Vehicles Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433 (United States)

2006-03-20T23:59:59.000Z

438

Iterative phase estimation  

E-Print Network (OSTI)

We give an iterative algorithm for phase estimation of a parameter theta, which is within a logarithmic factor of the Heisenberg limit. Unlike other methods, we do not need any entanglement or an extra rotation gate which can perform arbitrary rotations with almost perfect accuracy: only a single copy of the unitary channel and basic measurements are needed. Simulations show that the algorithm is successful. We also look at iterative phase estimation when depolarizing noise is present. It is seen that the algorithm is still successful provided the number of iterative stages is below a certain threshold.

Caleb J O'Loan

2009-04-22T23:59:59.000Z

439

Striped phases from holography  

E-Print Network (OSTI)

We discuss new types of second order phase transitions in holography by constructing striped black holes in D=4 with $AdS_{4}$ asymptotics. In the context of $AdS/CFT$, they provide the gravity duals to field theory phases in which translational symmetry is spontaneously broken due to the formation of current density waves. These black holes are associated to three dimensional CFTs at finite temperature and deformed by a uniform chemical potential. We numerically solve a non-linear system of PDEs in order to construct the black hole geometries and extract some of their thermodynamic properties.

Aristomenis Donos

2013-03-28T23:59:59.000Z

440

Linear phase compressive filter  

DOE Patents (OSTI)

A phase linear filter for soliton suppression is in the form of a laddered series of stages of non-commensurate low pass filters with each low pass filter having a series coupled inductance (L) and a reverse biased, voltage dependent varactor diode, to ground which acts as a variable capacitance (C). L and C values are set to levels which correspond to a linear or conventional phase linear filter. Inductance is mapped directly from that of an equivalent nonlinear transmission line and capacitance is mapped from the linear case using a large signal equivalent of a nonlinear transmission line.

McEwan, Thomas E. (Livermore, CA)

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Nuclear chiral dynamics and thermodynamics  

E-Print Network (OSTI)

This presentation reviews an approach to nuclear many-body systems based on the spontaneously broken chiral symmetry of low-energy QCD. In the low-energy limit, for energies and momenta small compared to a characteristic symmetry breaking scale of order 1 GeV, QCD is realized as an effective field theory of Goldstone bosons (pions) coupled to heavy fermionic sources (nucleons). Nuclear forces at long and intermediate distance scales result from a systematic hierarchy of one- and two-pion exchange processes in combination with Pauli blocking effects in the nuclear medium. Short distance dynamics, not resolved at the wavelengths corresponding to typical nuclear Fermi momenta, are introduced as contact interactions between nucleons. Apart from a set of low-energy constants associated with these contact terms, the parameters of this theory are entirely determined by pion properties and low-energy pion-nucleon scattering observables. This framework (in-medium chiral perturbation theory) can provide a realistic description of both isospin-symmetric nuclear matter and neutron matter. The importance of three-body forces is emphasized, and the role of explicit Delta(1232)-isobar degrees of freedom is investigated in detail. Nuclear chiral thermodynamics is developed and a calculation of the nuclear phase diagram is performed. This includes a successful description of the first-order phase transition from a nuclear Fermi liquid to an interacting Fermi gas and the coexistence of these phases below a critical temperature T_c. Density functional methods for finite nuclei based on this approach are also discussed. Effective interactions, their density dependence and connections to Landau Fermi liquid theory are outlined. Finally, the density and temperature dependence of the chiral (quark) condensate is investigated.

J. W. Holt; N. Kaiser; W. Weise

2013-04-23T23:59:59.000Z

442

Space and phase resolved ion energy and angular distributions in single-and dual-frequency capacitively coupled plasmas  

E-Print Network (OSTI)

Space and phase resolved ion energy and angular distributions in single- and dual of ion energy and angular distributions (IEADs) is critically important for anisotropic etching), the narrowing in angle and spread in energy of ions as they cross the sheath are definable functions

California at Los Angles, University of

443

Graded index and randomly oriented core-shell silicon nanowires with broadband and wide angle antireflection for photovoltaic cell applications  

E-Print Network (OSTI)

Antireflection with broadband and wide angle properties is important for a wide range of applications on photovoltaic cells and display. The SiOx shell layer provides a natural antireflection from air to the Si core absorption layer. In this work, we have demonstrated the random core-shell silicon nanowires with both broadband (from 400nm to 900nm) and wide angle (from normal incidence to 60\\degree) antireflection characteristics within AM1.5 solar spectrum. The graded index structure from the randomly oriented core-shell (Air/SiOx/Si) nanowires may provide a potential avenue to realize a broadband and wide angle antireflection layer.

Pignalosa, P; Qiao, L; Tseng, M; Yi, Yasha

2011-01-01T23:59:59.000Z

444

Liquid-gas phase transition in hot nuclei studied with INDRA  

E-Print Network (OSTI)

Thanks to the high detection quality of the INDRA array, signatures related to the dynamics (spinodal decomposition) and thermodynamics (negative microcanonical heat capacity) of a liquid-gas phase transition have been simultaneously studied in multifragmentation events in the Fermi energy domain. The correlation between both types of signals strongly supports the existence of a first order phase transition for hot nuclei.

B. Borderie; R. Bougault; P. Desesquelles; E. Galichet; B. Guiot; Ph. Lautesse; N. Le Neindre; J. Marie; M. Parlog; M. Pichon. M. F. Rivet; E. Rosato; G. Tabacaru; M. Vigilante; J. P. Wieleczko

2003-11-19T23:59:59.000Z

445

Modeling and computation of two phase geometric biomembranes using surface finite elements  

Science Conference Proceedings (OSTI)

Biomembranes consisting of multiple lipids may involve phase separation phenomena leading to coexisting domains of different lipid compositions. The modeling of such biomembranes involves an elastic or bending energy together with a line energy associated ... Keywords: Lipid bilayer, Multi-component membrane, Numerical simulation, Phase field method, Relaxation dynamics, Surface finite element method

Charles M. Elliott; Bjrn Stinner

2010-09-01T23:59:59.000Z

446

Evaluations of emitter clogging in drip irrigation by two-phase flow simulations and laboratory experiments  

Science Conference Proceedings (OSTI)

Emitter clogging will affect greatly the irrigation efficiency and the running cost of a drip irrigation system. If there is an effective method to predict the emitter clogging, the lost will be reduced to a minimum. A solid-liquid two-phase turbulent ... Keywords: Clogging, Computational fluid dynamics, Drip emitters, Drip irrigation, Two-phase flow

Wei Qingsong; Lu Gang; Liu Jie; Shi Yusheng; Dong Wenchu; Huang Shuhuai

2008-10-01T23:59:59.000Z

447

ECONOMIC RECOVERY OF OIL TRAPPED AT FAN MARGINS USING HIGH ANGLE WELLS AND MULTIPLE HYDRAULIC FRACTURES  

Science Conference Proceedings (OSTI)

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. A high-angle well will be drilled in the fan-margin portion of a slope-basin clastic reservoir and will be completed with multiple hydraulic-fracture treatments. Geologic modeling, reservoir characterization, and fine-grid reservoir simulation will be used to select the well location and orientation. Design parameters for the hydraulic-fracture treatments will be determined, in part, by fracturing an existing test well. Fracture azimuth will be predicted by passive seismic monitoring of a fracture-stimulation treatment in the test well using logging tools in an offset well. The long radius, near horizontal well was drilled during the first quarter of 1996. Well conditions resulted in the 7 in. production liner sticking approximately 900 ft off bottom. Therefore, a 5 in. production liner was necessary to case this portion of the target formation. Swept-out sand intervals and a poor cement bond behind the 5 in. liner precluded two of the three originally planned hydraulic fracture treatments. As a result, all pay intervals behind the 5 in. liner were perforated and stimulated with a non-acid reactive fluid. Following a short production period, the remaining pay intervals in the well (behind the 7 in. liner) were perforated. The well was returned to production to observe production trends and pressure behavior and assess the need to stimulate the new perforations.

Mike L. Laue

2001-09-28T23:59:59.000Z

448

Concept development for the ITER equatorial port visible/infrared wide angle viewing system  

Science Conference Proceedings (OSTI)

The ITER equatorial port visible/infrared wide angle viewing system concept is developed from the measurement requirements. The proposed solution situates 4 viewing systems in the equatorial ports 3, 9, 12, and 17 with 4 views each (looking at the upper target, the inner divertor, and tangentially left and right). This gives sufficient coverage. The spatial resolution of the divertor system is 2 times higher than the other views. For compensation of vacuum-vessel movements, an optical hinge concept is proposed. Compactness and low neutron streaming is achieved by orienting port plug doglegs horizontally. Calibration methods, risks, and R and D topics are outlined.

Reichle, R.; Beaumont, B.; Boilson, D.; Bouhamou, R.; Direz, M.-F.; Encheva, A.; Henderson, M.; Kazarian, F.; Lamalle, Ph.; Lisgo, S.; Mitteau, R.; Patel, K. M.; Pitcher, C. S.; Pitts, R. A.; Prakash, A.; Raffray, R.; Schunke, B.; Snipes, J.; Diaz, A. Suarez; Udintsev, V. S. [ITER Organization, Route de Vinon-sur-Verdon, 13115 St Paul-lez-Durance (France); and others

2012-10-15T23:59:59.000Z

449

COMPARISON OF OFF-LINE IR BUMP AND ACTION-ANGLE KICK MINIMIZATION.  

Science Conference Proceedings (OSTI)

The interaction region bump (IR bump) nonlinear correction method has been used for the sextupole and octupole field error on-line corrections in the Relativistic Heavy Ion Collider (RHIC) . Some differences were found for the sextupole and octupole corrector strengths between the on-line IR bump correction and the predictions from the action-angle kick minimization. In this article, we compare the corrector strengths from these two methods based on the RHIC Blue ring lattice with the IR nonlinear modeling. The comparison confirms the differences between resulting corrector strengths. And the reason for the differences is found and discussed.

LUO, Y.; PILAT, F.; PTITSYN, V.; TRBOJEVIC, D.; WEI, J.

2005-05-16T23:59:59.000Z

450

Neutrino Mass Models and the Implications of a Non-Zero Reactor Angle  

E-Print Network (OSTI)

In this talk we survey some of the recent promising developments in the search for the theory behind neutrino mass and mixing, and indeed all fermion masses and mixing. The talk is organized in terms of a neutrino mass models decision tree according to which the answers to experimental questions provide sign posts to guide us through the maze of theoretical models eventually towards a complete theory of flavour and unification. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.

S. F. King

2009-04-21T23:59:59.000Z

451

Neutrino Mass Models and the Implications of a Non-Zero Reactor Angle  

E-Print Network (OSTI)

In this talk we survey some of the recent promising developments in the search for the theory behind neutrino mass and mixing, and indeed all fermion masses and mixing. The talk is organized in terms of a neutrino mass models decision tree according to which the answers to experimental questions provide sign posts to guide us through the maze of theoretical models eventually towards a complete theory of flavour and unification. We also discuss the theoretical implications of the measurement of a non-zero reactor angle, as hinted at by recent experimental measurements.

King, S F

2009-01-01T23:59:59.000Z

452

Use of Small Angle Neutron Scattering to Study Various Properties of Wool and Mohair Fibres  

SciTech Connect

To maintain a competitive edge in the wool and mohair industry, a detailed knowledge and understanding of the properties of wool fibres is essential. Standard techniques are used to determine fibre diameter, length and strength; however, properties such as hydroscopicity, lustre and changes in fibre structure following chemical or mechanical treatment are not so well understood. The unique capabilities of small angle neutron scattering to study changes in the supermolecular structure of wool fibres, particularly at the level of the microfibril-matrix complex, have been used to provide previously unknown features of the fibres. The results of these studies are presented.

Franklyn, C. B. [Radiation Science Department, Necsa, PO Box 582, Pretoria 0001 (South Africa); Toeroek, Gy. [Research Institute for Solid State Physics and Optics, H-1525 Budapest, POB 49 (Hungary)

2011-12-13T23:59:59.000Z

453

Scanning angle Raman spectroscopy: Investigation of Raman scatter enhancement techniques for chemical analysis  

SciTech Connect

This thesis outlines advancements in Raman scatter enhancement techniques by applying evanescent fields, standing-waves (waveguides) and surface enhancements to increase the generated mean square electric field, which is directly related to the intensity of Raman scattering. These techniques are accomplished by employing scanning angle Raman spectroscopy and surface enhanced Raman spectroscopy. A 1064 nm multichannel Raman spectrometer is discussed for chemical analysis of lignin. Extending dispersive multichannel Raman spectroscopy to 1064 nm reduces the fluorescence interference that can mask the weaker Raman scattering. Overall, these techniques help address the major obstacles in Raman spectroscopy for chemical analysis, which include the inherently weak Raman cross section and susceptibility to fluorescence interference.

Meyer, Matthew W. [Ames Laboratory

2013-03-14T23:59:59.000Z

454

Solar heat gain coefficient of complex fenestrations with a venetian blind for differing slat tilt angles  

DOE Green Energy (OSTI)

Measured bidirectional transmittances and reflectances of a buff-colored venetian blind together with a layer calculation scheme developed in previous publications are utilized to produce directional-hemispherical properties for the venetian blind layer and solar heat gain coefficients for the blind in combination with clear double glazing. Results are presented for three blind slat tilt angles and for the blind mounted either interior to the double glazing or between the glass panes. Implications of the results for solar heat gain calculations are discussed in the context of sun positions for St. Louis, MO.

Klems, J.H.; Warner, J.L.

1996-08-01T23:59:59.000Z

455

Solar Dynamics | Open Energy Information  

Open Energy Info (EERE)

Dynamics Jump to: navigation, search Name Solar Dynamics Place Ottumwa, Iowa Zip IA 52501 Sector Solar Product Solar Dynamics is a US-based solar powered attic roof vents...

456

DELTA PHASE PLUTONIUM ALLOYS  

DOE Patents (OSTI)

Delta-phase plutonium alloys were developed suitable for use as reactor fuels. The alloys consist of from 1 to 4 at.% zinc and the balance plutonium. The alloys have good neutronic, corrosion, and fabrication characteristics snd possess good dimensional characteristics throughout an operating temperature range from 300 to 490 deg C.

Cramer, E.M.; Ellinger, F.H.; Land. C.C.

1960-03-22T23:59:59.000Z

457

Examples of Phase Diagrams  

Science Conference Proceedings (OSTI)

...The phase diagram of the lead-tin system ( Fig. 31 ) shows the importance of the low-melting eutectic in this system to the success of lead-tin solders. While solders having tin contents between 18.3 to 61.9%

458

Refusing to Twist: Demonstration of a Line Hexatic Phase in DNA Liquid Crystals  

Science Conference Proceedings (OSTI)

We report conclusive high resolution small angle x-ray scattering evidence that long DNA fragments form an untwisted line hexatic phase between the cholesteric and the crystalline phases. The line hexatic phase is a liquid-crystalline phase with long-range hexagonal bond-orientational order, long-range nematic order, but liquidlike, i.e., short-range, positional order. So far, it has not been seen in any other three dimensional system. By line-shape analysis of x-ray scattering data we found that positional order decreases when the line hexatic phase is compressed. We suggest that such anomalous behavior is a result of the chiral nature of DNA molecules. (c) 2000 The American Physical Society.

Strey, H. H. [Department of Polymer Science and Engineering, University of Massachusetts Amherst, Amherst, Massachusetts 01003 (United States); NICHD/LPSB, National Institutes of Health, Building 12A/2041, Bethesda, Maryland 20892-5626 (United States); Wang, J. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Corporate Strategic Research, ExxonMobil Research and Engineering Company, Route 22 East, Annandale, New Jersey 08801 (United States); Podgornik, R. [NICHD/LPSB, National Institutes of Health, Building 12A/2041, Bethesda, Maryland 20892-5626 (United States); Rupprecht, A. [Physical Chemistry, Arrhenius Laboratory, University of Stockholm, Stockholm, (Sweden); Yu, L. [NIAMS/LPB, National Institutes of Health, Building 6/408, Bethesda, Maryland 20892 (United States); Parsegian, V. A. [NICHD/LPSB, National Institutes of Health, Building 12A/2041, Bethesda, Maryland 20892-5626 (United States); Sirota, E. B. [Corporate Strategic Research, ExxonMobil Research and Engineering Company, Route 22 East, Annandale, New Jersey 08801 (United States)

2000-04-03T23:59:59.000Z

459

Dynamic Behavior of Materials V  

Science Conference Proceedings (OSTI)

Dynamic Characterization of Cast and Wrought Uranium-Niobium Metals Dynamic Deformation Response of High-Strength Ni-Containing Steels.

460

Downslope Flows on a Low-Angle Slope and Their Interactions with Valley Inversions. Part II: Numerical Modeling  

Science Conference Proceedings (OSTI)

The characteristics of well-developed downslope winds observed by tethered balloon soundings at multiple locations over a low-angle slope in the Salt Lake Valley are studied using the Regional Atmospheric Modeling System (RAMS). The model ...

Shiyuan Zhong; C. David Whiteman

2008-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamic phase angle" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Real Time Selective Harmonic Minimization for Multilevel Inverters Connected to Solar Panels Using Artificial Neural Network Angle Generation  

SciTech Connect

This work approximates the selective harmonic elimination problem using artificial neural networks (ANNs) to generate the switching angles in an 11-level full-bridge cascade inverter powered by five varying dc input sources. Each of the five full bridges of the cascade inverter was connected to a separate 195-W solar panel. The angles were chosen such that the fundamental was kept constant and the low-order harmonics were minimized or eliminated. A nondeterministic method is used to solve the system for the angles and to obtain the data set for the ANN training. The method also provides a set of acceptable solutions in the space where solutions do not exist by analytical methods. The trained ANN is a suitable tool that brings a small generalization effect on the angles' precision and is able to perform in real time (50-/60-Hz time window).

Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL; Filho, Faete [ORNL; Cao, Yue [ORNL

2011-01-01T23:59:59.000Z

462

Interface dynamics under nonequilibrium conditions: from a self-propelled droplet to dynamic pattern evolution  

E-Print Network (OSTI)

In this article, we describe the instability of a contact line under nonequilibrium conditions mainly based on the results of our recent studies. Two experimental examples are presented: the self-propelled motion of a liquid droplet and spontaneous dynamic pattern formation. For the self-propelled motion of a droplet, we introduce an experiment in which a droplet of aniline sitting on an aqueous layer moves spontaneously at an air-water interface. The spontaneous symmetry breaking of Marangoni-driven spreading causes regular motion. In a circular Petri dish, the droplet exhibits either beeline motion or circular motion. On the other hand, we show the emergence of a dynamic labyrinthine pattern caused by dewetting of a metastable thin film from the air-water interface. The contact line between the organic phase and aqueous phase forms a unique spatio-temporal pattern characterized as a dynamic labyrinthine. Motion of the contact line is controlled by diffusion processes. We propose a theoretical model to interpret essential aspects of the observed dynamic behavior.

Yong-Jun Chen; Kenichi Yoshikawa

2012-08-22T23:59:59.000Z

463

Time-Resolved Small-Angle X-ray Scattering Studies Revealed Three Kinetic  

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June 2010 June 2010 Time-Resolved Small-Angle X-ray Scattering Studies Revealed Three Kinetic Stages of a T=4 Virus Maturation Most eukaryotic viruses, including HIV, influenza and herpes viruses, undergo maturation when transitioning from the noninfectious provirion to the infectious virion. Maturation processes involve reorganization of viral quaternary structure to defend viral gene from the cellular defense mechanism and lead to effective transfection. Nudaurelia capensis omega virus, NwV, is a T=4, non-enveloped, icosahedral, single strand RNA virus, where T is the triangulation number defining an icosahedral lattice of the virus capsid structure. Virus like particles (VLPs) of NwV exhibit large pH-dependent conformational changes (LCC) when the procapsid, purified at pH=7.6, (~480 Å) is exposed to pH=5.0, resulting in ~400 Å particles (Figure 1). In response to the LCC, an auto-proteolysis occurs in which each of 240 subunits is cleaved at Asn570-Phe571 (1). We investigated this pH-induced maturation by equilibrium and time-resolved small angle X-ray scattering (SAXS) at SSRL beam line 4-2.