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1

Dynamic Evolution for Risk-Neutral Densities  

E-Print Network (OSTI)

We solved the scaled formulation for problems (7) and (10) and obtained the dynamic evolution for the densities (see Figure 1). For this data set, we.

2

Multiscale FEM-MD schema  

Science Conference Proceedings (OSTI)

... coupling finite element modeling (FEM) to atomistic Molecular Dynamics (MD) 1 ... for using extremely high (very unrealistic) indentation rates that are ...

2013-06-27T23:59:59.000Z

3

Md. Saifur Rahaman Md. Saifur Rahaman  

E-Print Network (OSTI)

of Chemical and Environmental Engineering "Environmental Applications of Nanotechnology" Advisor: ProfMd. Saifur Rahaman Resume 1 Md. Saifur Rahaman Department of Chemical and Environmental Engineering from Wastewater through Struvite Crystallization in a Fluidized Bed Reactor: Kinetics, Hydrodynamics

Elimelech, Menachem

4

Local Restaurants - Gaithersburg, MD  

Science Conference Proceedings (OSTI)

... Subway 16 Bureau Dr. Gaithersburg, MD (301) 527-8988. Thai Tanium 657 Center Point Way Gaithersburg, MD (301) 990-3699. ...

2013-07-25T23:59:59.000Z

5

Dynamical density functional theory for dense atomic liquids  

E-Print Network (OSTI)

Starting from Newton's equations of motion, we derive a dynamical density functional theory (DDFT) applicable to atomic liquids. The theory has the feature that it requires as input the Helmholtz free energy functional from equilibrium density functional theory. This means that, given a reliable equilibrium free energy functional, the correct equilibrium fluid density profile is guaranteed. We show that when the isothermal compressibility is small, the DDFT generates the correct value for the speed of sound in a dense liquid. We also interpret the theory as a dynamical equation for a coarse grained fluid density and show that the theory can be used (making further approximations) to derive the standard mode coupling theory that is used to describe the glass transition. The present theory should provide a useful starting point for describing the dynamics of inhomogeneous atomic fluids.

A. J. Archer

2006-04-25T23:59:59.000Z

6

Harvesting graphics power for MD simulations  

E-Print Network (OSTI)

We discuss an implementation of molecular dynamics (MD) simulations on a graphic processing unit (GPU) in the NVIDIA CUDA language. We tested our code on a modern GPU, the NVIDIA GeForce 8800 GTX. Results for two MD algorithms suitable for short-ranged and long-ranged interactions, and a congruential shift random number generator are presented. The performance of the GPU's is compared to their main processor counterpart. We achieve speedups of up to 80, 40 and 150 fold, respectively. With newest generation of GPU's one can run standard MD simulations at 10^7 flops/$.

J. A. van Meel; A. Arnold; D. Frenkel; S. F. Portegies Zwart; R. G. Belleman

2007-09-20T23:59:59.000Z

7

Density Functional Theory for the Photoionization Dynamics of Uracil  

E-Print Network (OSTI)

Photoionization dynamics of the RNA base Uracil is studied in the framework of Density Functional Theory (DFT). The photoionization calculations take advantage of a newly developed parallel version of a multicentric approach to the calculation of the electronic continuum spectrum which uses a set of B-spline radial basis functions and a Kohn-Sham density functional hamiltonian. Both valence and core ionizations are considered. Scattering resonances in selected single-particle ionization channels are classified by the symmetry of the resonant state and the peak energy position in the photoelectron kinetic energy scale; the present results highlight once more the site specificity of core ionization processes. We further suggest that the resonant structures previously characterized in low-energy electron collision experiments are partly shifted below threshold by the photoionization processes. A critical evaluation of the theoretical results providing a guide for future experimental work on similar biosystems.

Toffoli, D; Gianturco, F A; Lucchese, R R

2007-01-01T23:59:59.000Z

8

Hybrid Dynamic Density Functional Theory for Polymer Melts and Blends  

E-Print Network (OSTI)

We propose a high-speed and accurate hybrid dynamic density functional theory for the computer simulations of the phase separation processes of polymer melts and blends. The proposed theory is a combination of the dynamic self-consistent field (SCF) theory and a time-dependent Ginzburg-Landau type theory with the random phase approximation (GRPA). The SCF theory is known to be accurate in evaluating the free energy of the polymer systems in both weak and strong segregation regions although it has a disadvantage of the requirement of a considerable amount of computational cost. On the other hand, the GRPA theory has an advantage of much smaller amount of required computational cost than the SCF theory while its applicability is limited to the weak segregation region. To make the accuracy of the SCF theory and the high-performance of the GRPA theory compatible, we adjust the chemical potential of the GRPA theory by using the SCF theory every constant time steps in the dynamic simulations. The performance of the GRPA and the hybrid theories is tested by using several systems composed of an A/B homopolymer, an AB diblock copolymer, or an ABC triblock copolymer. Using the hybrid theory, we succeeded in reproducing the metastable complex phase-separated domain structures of an ABC triblock copolymer observed by experiments.

Takashi Honda; Toshihiro Kawakatsu

2006-09-05T23:59:59.000Z

9

Dynamical eigenfunctions and critical density in loop quantum cosmology  

E-Print Network (OSTI)

We offer a new, physically transparent argument for the existence of the critical, universal maximum matter density in loop quantum cosmology for the case of a flat Friedmann-Lemaitre-Robertson-Walker cosmology with scalar matter. The argument is based on the existence of a sharp exponential ultraviolet cutoff in momentum space on the eigenfunctions of the quantum cosmological dynamical evolution operator (the gravitational part of the Hamiltonian constraint), attributable to the fundamental discreteness of spatial volume in loop quantum cosmology. The existence of the cutoff is proved directly from recently found exact solutions for the eigenfunctions for this model. As a consequence, the operators corresponding to the momentum of the scalar field and the spatial volume approximately commute. The ultraviolet cutoff then implies that the scalar momentum, though not a bounded operator, is in effect bounded on subspaces of constant volume, leading to the upper bound on the expectation value of the matter densit...

Craig, David A

2012-01-01T23:59:59.000Z

10

DFT-based molecular dynamics as a new tool for computational biology: first applications and perspective  

Science Conference Proceedings (OSTI)

Static and molecular dynamics (MD) calculations based on density-functional theory (DFT) are emerging as a valuable means for simulations in the field of biology, especially when coupled with classical simulations. In this contribution, we point out ...

W. Andreoni; A. Curioni; T. Mordasini

2001-05-01T23:59:59.000Z

11

Dynamical instabilities in density-dependent hadronic relativistic models  

Science Conference Proceedings (OSTI)

Unstable modes in asymmetric nuclear matter (ANM) at subsaturation densities are studied in the framework of relativistic mean-field density-dependent hadron models. The size of the instabilities that drive the system are calculated and a comparison with results obtained within the nonlinear Walecka model is presented. The distillation and antidistillation effects are discussed.

Santos, A. M.; Brito, L.; Providencia, C. [Centro de Fisica Teorica, Department of Physics, University of Coimbra, P-3004-516 Coimbra (Portugal)

2008-04-15T23:59:59.000Z

12

Category:Baltimore, MD | Open Energy Information  

Open Energy Info (EERE)

MD MD Jump to: navigation, search Go Back to PV Economics By Location Media in category "Baltimore, MD" The following 16 files are in this category, out of 16 total. SVFullServiceRestaurant Baltimore MD Baltimore Gas & Electric Co.png SVFullServiceRestauran... 69 KB SVQuickServiceRestaurant Baltimore MD Baltimore Gas & Electric Co.png SVQuickServiceRestaura... 67 KB SVHospital Baltimore MD Baltimore Gas & Electric Co.png SVHospital Baltimore M... 69 KB SVLargeHotel Baltimore MD Baltimore Gas & Electric Co.png SVLargeHotel Baltimore... 69 KB SVLargeOffice Baltimore MD Baltimore Gas & Electric Co.png SVLargeOffice Baltimor... 69 KB SVMediumOffice Baltimore MD Baltimore Gas & Electric Co.png SVMediumOffice Baltimo... 68 KB SVMidriseApartment Baltimore MD Baltimore Gas & Electric Co.png

13

The Circulation Dynamics and Thermodynamics of Upper Ocean Density Fronts  

Science Conference Proceedings (OSTI)

This paper extends a previous hydrodynamic circulation model of established, persistent upper ocean density fronts by including a thermodynamic or buoyancy equation in the integral treatment. An analysis is also conducted of the variables related ...

Richard W. Garvine

1980-12-01T23:59:59.000Z

14

Dynamic Tensile Extrusion of High-density Polyethylene  

Science Conference Proceedings (OSTI)

Depending on the extrusion ratios and velocities HDPE damage varies gross ... Characterization of the Dynamic Behavior of Recycled Polypropylene-based Composites ... Shock Compression Behavior of Bi-material Powder Composites with ...

15

Fast plane wave density functional theory molecular dynamics calculations on multi-GPU machines  

Science Conference Proceedings (OSTI)

Plane wave pseudopotential (PWP) density functional theory (DFT) calculation is the most widely used method for material simulations, but its absolute speed stagnated due to the inability to use large scale CPU based computers. By a drastic redesign ... Keywords: Density functional theory, Electronic structure, First-principles, GPU, Molecular dynamics, Plane wave pseudopotential

Weile Jia, Jiyun Fu, Zongyan Cao, Long Wang, Xuebin Chi, Weiguo Gao, Lin-Wang Wang

2013-10-01T23:59:59.000Z

16

DENSITY  

Science Conference Proceedings (OSTI)

... Table 2: Principal mineral phases found in the granite rock. Mineral phase. ... Table 4. Average density of 12 granite rocks by Archimedes and CT. ...

2007-01-08T23:59:59.000Z

17

Coupled-channels density-matrix approach to low-energy nuclear reaction dynamics  

E-Print Network (OSTI)

Atomic nuclei are complex, quantum many-body systems whose structure manifests itself through intrinsic quantum states associated with different excitation modes or degrees of freedom. Collective modes (vibration and/or rotation) dominate at low energy (near the ground-state). The associated states are usually employed, within a truncated model space, as a basis in (coherent) coupled channels approaches to low-energy reaction dynamics. However, excluded states can be essential, and their effects on the open (nuclear) system dynamics are usually treated through complex potentials. Is this a complete description of open system dynamics? Does it include effects of quantum decoherence? Can decoherence be manifested in reaction observables? In this contribution, I discuss these issues and the main ideas of a coupled-channels density-matrix approach that makes it possible to quantify the role and importance of quantum decoherence in low-energy nuclear reaction dynamics. Topical applications, which refer to understanding the astrophysically important collision $^{12}$C + $^{12}$C and achieving a unified quantum dynamical description of relevant reaction processes of weakly-bound nuclei, are highlighted.

Alexis Diaz-Torres

2010-09-02T23:59:59.000Z

18

Density Functional Theory and Molecular Dynamics Studies on Energetics and Kinetics for Electro-Active Polymers: PVDF and P(VDF-TrFE)  

E-Print Network (OSTI)

We use first principles methods to study static and dynamical mechanical properties of the ferroelectric polymer Poly(vinylidene fluoride) (PVDF) and its copolymer with trifluoro ethylene (TrFE). We use density functional theory [within the generalized gradient approximation (DFT-GGA)] to calculate structures and energetics for various crystalline phases for PVDF and P(VDF-TrFE). We find that the lowest energy phase for PVDF is a non-polar crystal with a combination of trans (T) and gauche (G) bonds; in the case of the copolymer the role of the extra (bulkier) F atoms is to stabilize T bonds. This leads to the higher crystallinity and piezoelectricity observed experimentally. Using the MSXX first principles-based force field (FF) with molecular dynamics (MD), we find that the energy barrier necessary to nucleate a kink (gauche pairs separated by trans bonds) in an all-T crystal is much lower (14.9 kcal/mol) in P(VDF-TrFE) copolymer than in PVDF (24.8 kcal/mol). This correlates with the observation that the polar phase of the copolymer exhibits a solid-solid a transition to a non-polar phase under heating while PVDF directly melts. We also studied the mobility of an interface between a polar and non-polar phases under uniaxial stress; we find a lower threshold stress and a higher mobility in the copolymer as compared with PVDF. Finally, considering plastic deformation under applied shear, we find that the chains for P(VDF-TrFE) have a very low resistance to sliding, particularly along the chain direction. The atomistic characterization of these "unit mechanisms" provides essential input to mesoscopic or macroscopic models of electro-active polymers.

H. B. Su; Alejandro Strachan; William A. Goddard III

2004-08-09T23:59:59.000Z

19

Spontaneous fission of /sup 259/Md  

SciTech Connect

The mass and kinetic energy distributions of fission fragments from the spontaneous fission of th newly discovered nuclide /sup 259/Md were obtained. /sup 259/Md was identified as the E. C. daughter of /sup 259/No, and was found to decay entirely (> 95%) by spontaneous fission with a 95-min half-life. From the kinetic energies measured for 397 pairs of coincident fragments, a mass distribution was derived that is symmetric with sigma = 13 amu. /sup 259/Md, together with /sup 258/Fm and /sup 259/Fm, form a select group of three nuclides whose mass division in spontaneous fission is highly symmetric. Unlike the total-kinetic-energy (TKE) distributions of /sup 258/Fm and /sup 259/Fm, which peak at approx. = to 240 MeV, this distribution for /sup 259/Md is broad and is 50 MeV lower in energy. Analysis of the mass and energy distributions shows that events near mass symmetry also exhibit a broad TKE distribution, with one-third of the symmetric events having TKEs less than 200 MeV. The associated of low TKEs with symmetric mass division in the fission of very heavy actinides is anomalous and inconsistent with theories based upon the emergence of fragment shells near the scission point. Either three-body fragmentation or peculiar fragment shapes are assumed as the cause for the large consumption of Coulomb energy observed for a significant fraction of symmetric fissions in /sup 259/Md. 6 figures.

Hulet, E.K.; Wild, J.F.; Lougheed, R.W.; Baisden, P.A.; Landrum, J.H.; Dougan, R.J.; Mustafa, M.; Ghiorso, A.; Nitschke, J.M.

1979-05-04T23:59:59.000Z

20

Compute Node MD3000 Storage Array  

E-Print Network (OSTI)

Compute Node MD3000 Storage Array Dell 2950 Head Node 24-Port Switch Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node 24-Port Switch Dell 2950

Weber, David J.

Note: This page contains sample records for the topic "dynamics md density" 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

Heart Failure Jason Ryan, MD, MPH  

E-Print Network (OSTI)

1 Heart Failure Jason Ryan, MD, MPH Director, UCONN Heart Failure Center University of Connecticut,084,000 $34.8 billion Background on Heart Failure Heart failure (HF) is a major public health problem resulting in substantial morbidity and mortality 1American Heart Association.2008 Heart and Stroke

Oliver, Douglas L.

22

Visible and dark matter in M 31 - II. A dynamical model and dark matter density distribution  

E-Print Network (OSTI)

In the present paper we derive the density distribution of dark matter (DM) in a well-observed nearby disc galaxy, the Andromeda galaxy. From photometrical and chemical evolution models constructed in the first part of the study (Tamm, Tempel & Tenjes 2007 (arXiv:0707.4375), hereafter Paper I) we can calculate the mass distribution of visible components. In the dynamical model we calculate stellar rotation velocities along the major axis and velocity dispersions along the major, minor and intermediate axes of the galaxy. Comparing the calculated values with the collected observational data, we find the amount of DM, which must be added to reach an agreement with the observed rotation and dispersion data. We conclude that within the uncertainties, the DM distributions by Moore, Burkert, isothermal, Navarro, Frenk & White (NFW) and Navarro et al. 2004 (N04) fit with observations. The NFW and N04 density distributions give the best fit with observations. The total mass of M 31 with the NFW DM distributio...

Tempel, Elmo; Tenjes, Peeter

2007-01-01T23:59:59.000Z

23

Visible and dark matter in M 31 - II. A dynamical model and dark matter density distribution  

E-Print Network (OSTI)

In the present paper we derive the density distribution of dark matter (DM) in a well-observed nearby disc galaxy, the Andromeda galaxy. From photometrical and chemical evolution models constructed in the first part of the study (Tamm, Tempel & Tenjes 2007 (arXiv:0707.4375), hereafter Paper I) we can calculate the mass distribution of visible components (the bulge, the disc, the stellar halo, the outer diffuse stellar halo). In the dynamical model we calculate stellar rotation velocities along the major axis and velocity dispersions along the major, minor and intermediate axes of the galaxy assuming triaxial velocity dispersion ellipsoid. Comparing the calculated values with the collected observational data, we find the amount of DM, which must be added to reach an agreement with the observed rotation and dispersion data. We conclude that within the uncertainties, the DM distributions by Moore, Burkert, Navarro, Frenk & White (NFW) and the Einasto fit with observations nearly at all distances. The NFW and Einasto density distributions give the best fit with observations. The total mass of M 31 with the NFW DM distribution is 1.19*10^12 M_sun, the ratio of the DM mass to the visible mass is 10.0. For the Einasto DM distribution, these values are 1.28*10^12 M_sun and 10.8. The ratio of the DM mass to the visible mass inside the Holmberg radius is 1.75 for the NFW and the Einasto distributions. For different cuspy DM distributions, the virial mass is in a range 6.9-7.9*10^11 M_sun and the virial radius is ~150 kpc. The DM mean densities inside 10 pc for cusped models are 33 and 16 M_sun pc^-3 for the NFW and the Einasto profiles, respectively. For the cored Burkert profile, this value is 0.06 M_sun pc^-3.

Elmo Tempel; Antti Tamm; Peeter Tenjes

2007-07-30T23:59:59.000Z

24

Free Energy Calculation in MD Simulation  

E-Print Network (OSTI)

Free Energy Calculation in MD Simulation #12;Basic Thermodynamics Helmoholtz free energy A = U ­ TS + i Ni dA = wrev (reversible, const N V T) eq (22.9) McQuarrie & Simon Gibbs free energy G = U;Implication of Free Energy A B Keq = [A]/[B] Keq = exp (-G0 /RT) G0 = -RT ln Keq G = G0 + RT ln Q G > 0

Nielsen, Steven O.

25

DOE - Office of Legacy Management -- Johns Hopkins University - MD 02  

Office of Legacy Management (LM)

Johns Hopkins University - MD 02 Johns Hopkins University - MD 02 FUSRAP Considered Sites Site: JOHNS HOPKINS UNIVERSITY (MD.02 ) Eliminated from further consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: Baltimore , Maryland MD.02-1 Evaluation Year: 1987 MD.02-2 Site Operations: Conducted spectroscopic studies under contract number AT(49-1)-309. MD.02-1 Site Disposition: Eliminated - Potential for contamination considered remote based on limited quantities of material used in a controlled environment MD.02-2 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Tritium MD.02-1 Radiological Survey(s): None Indicated Site Status: Eliminated from further consideration under FUSRAP Also see Documents Related to JOHNS HOPKINS UNIVERSITY

26

Steady-State Dynamics of a Density Current in an f-Plane Nonlinear Shallow-Water Model  

Science Conference Proceedings (OSTI)

The authors study the nonlinear dynamics of a density current generated by a diabatic source in a rotating and a nonrotating system, both in the presence and in the absence of frictional losses, using a steady-state hydrostatic shallow-water ...

Giovanni A. Dalu; Marina Baldi

2010-02-01T23:59:59.000Z

27

Improved interval estimation of long run response from a dynamic linear model: A highest density region approach  

Science Conference Proceedings (OSTI)

This paper proposes a new method of interval estimation for the long run response (or elasticity) parameter from a general linear dynamic model. We employ the bias-corrected bootstrap, in which small sample biases associated with the parameter estimators ... Keywords: ARDL model, Bias-correction, Bootstrapping, Highest density region, Long run elasticity

Jae H. Kim; Iain Fraser; Rob J. Hyndman

2011-08-01T23:59:59.000Z

28

Detonation shock dynamics calibration for pBX 9502 with temperature, density, and material lot variations  

Science Conference Proceedings (OSTI)

We present a methodology for scaling the detonation shock dynamics D{sub n}[{kappa}] calibration function to accommodate variations in the HE starting material. We apply our model to the insensitive TATB-based explosive PBX 9502, for which we have enough front curvature rate stick data to characterize three material attributes: initial temperature T{sub 0}, nominal density {rho}{sub 0}, and manufacturing lot (representing different microstructures). A useful feature of the model is that it returns an absolute estimate for the reaction zone thickness, {delta}. Lacking demonstrated material metrics(s), we express microstructural variation indirectly, in terms of its effect on {delta}. This results in a D{sub n}[{kappa}] function that depends on T{sub 0}, {rho}{sub 0}, and {delta}. After examining the separate effects of each parameter on D{sub n}[{kappa}], we compute an arc geometry as a validation problem. We compare the calculation to a PBX 9502 arc experiment that was pressed from one of the calibrated HE lots. The agreement between the model and experiment is excellent. We compute worst, nominal, and best-performing material parameter combinations to show how much difference accrues throughout the arc.

Hill, Larry G [Los Alamos National Laboratory; Aslam, Tariq D [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

29

More accurate and efficient bath spectral densities from super-resolution  

E-Print Network (OSTI)

Quantum transport and other phenomena are typically modeled by coupling the system of interest to an environment, or bath, held at thermal equilibrium. Realistic bath models are at least as challenging to construct as models for the quantum systems themselves, since they must incorporate many degrees of freedom that interact with the system on a wide range of timescales. Owing to computational limitations, the environment is often modeled with simple functional forms, with a few parameters fit to experiment to yield semi-quantitative results. Growing computational resources have enabled the construction of more realistic bath models from molecular dynamics (MD) simulations. In this paper, we develop a numerical technique to construct these atomistic bath models with better accuracy and decreased cost. We apply a novel signal processing technique, known as super-resolution, combined with a dictionary of physically-motivated bath modes to derive spectral densities from MD simulations. Our approach reduces the required simulation time and provides a more accurate spectral density than can be obtained via standard Fourier transform methods. Moreover, the spectral density is provided as a convenient closed-form expression which yields an analytic time-dependent bath kernel. Exciton dynamics of the Fenna-Matthews-Olsen light-harvesting complex are simulated with a second order time-convolutionless master equation, and spectral densities constructed via super-resolution are shown to reproduce the dynamics using only a quarter of the amount of MD data.

Thomas Markovich; Samuel M. Blau; John Parkhill; Christoph Kreisbeck; Jacob N. Sanders; Xavier Andrade; Alán Aspuru-Guzik

2013-07-16T23:59:59.000Z

30

DOE - Office of Legacy Management -- Maryland Disposal Site - MD 05  

Office of Legacy Management (LM)

Maryland Disposal Site - MD 05 Maryland Disposal Site - MD 05 FUSRAP Considered Sites Site: MARYLAND DISPOSAL SITE (MD.05 ) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: Baltimore - Vicinity , Maryland MD.05-1 Evaluation Year: 1989 MD.05-1 Site Operations: Proposed disposal site - never developed. MD.05-1 Site Disposition: Eliminated Radioactive Materials Handled: None Indicated Primary Radioactive Materials Handled: None Indicated Radiological Survey(s): None Indicated Site Status: Eliminated from consideration under FUSRAP Also see Documents Related to MARYLAND DISPOSAL SITE MD.05-1 - Report (DOE/OR/20722-131 Revision 0); Site Plan for the Maryland Disposal Site; April 1989 Historical documents may contain links which are no longer valid or to

31

Optimization of density functional tight-binding and classical reactive molecular dynamics for high-throughput simulations of carbon materials  

Science Conference Proceedings (OSTI)

Carbon materials and nanostructures (fullerenes, nanotubes) are promising building blocks of nanotechnology. Potential applications include optical and electronic devices, sensors, and nano-scale machines. The multiscale character of processes related ... Keywords: ACM proceedings, BLAS, Cray XT5, LAPACK, advanced materials, density-functional tight binding, high-throughput, linear algebra, material science, molecular dynamics, multiscale-modeling, quantum chemistry, scientific libraries, scientific-computing

Jacek Jakowski; Bilel Hadri; Steven J. Stuart; Predrag Krstic; Stephan Irle; Dulma Nugawela; Sophya Garashchuk

2012-07-01T23:59:59.000Z

32

Oral Histories: Pathologist Clarence Lushbaugh, M.D.  

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

3 HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Pathologist Clarence Lushbaugh, M.D. Conducted October 5, 1994 United States Department of Energy Office of...

33

DOE - Office of Legacy Management -- Max Zuckerman and Sons Inc - MD 04  

Office of Legacy Management (LM)

Inc - MD 04 Inc - MD 04 FUSRAP Considered Sites Site: MAX ZUCKERMAN & SONS, INC. (MD.04 ) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: Maryland Alloys Corporation MD.04-1 Location: 5245 Fairlawn Avenue , Baltimore , Maryland MD.04-2 Evaluation Year: 1994 MD.04-1 MD.04-3 Site Operations: Scrap metals broker that arranged purchases of materials for third party buyers. MD.04-2 MD.04-4 Site Disposition: Eliminated - Potential for contamination remote MD.04-3 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Uranium (Q-11) Oxide/Residue MD.04-2 MD.04-4 Radiological Survey(s): Yes MD.04-1 Site Status: Eliminated from consideration under FUSRAP MD.04-3 Also see Documents Related to MAX ZUCKERMAN & SONS, INC.

34

Net Zero Residential Test Facility Gaithersburg, MD Solar Photovoltaic Panels  

E-Print Network (OSTI)

1 Net Zero Residential Test Facility Gaithersburg, MD Solar Photovoltaic Panels Solar Thermal R-35 Rim Joist Area 5" open cell spray foam 2" mineral wool insulation blanket R-10 Basement Slab electric WH #12;NZERTF Gaithersburg, MD Solar Photovoltaic Array Roof Mounted South half of main roof

Oak Ridge National Laboratory

35

Circulation in the Alboran See as Determined by Quasi-Synoptic Hydrographic Observations. Part II: Mesoscale Ageostrophic Motion Diagnosed through Density Dynamical Assimilation  

Science Conference Proceedings (OSTI)

The 3D velocity field in the Alboran Sea (Western-Mediterranean) is diagnosed through density dynamical assimilation in a primitive equation (PE) model with mesoscale resolution. The ageostrophic motion is computed from fields produced by short-...

Álvaro Viúdez; Robert L. Haney; Joaquín Tintoré

1996-05-01T23:59:59.000Z

36

Study of fusion dynamics using Skyrme energy density formalism with different surface corrections  

E-Print Network (OSTI)

Within the framework of Skyrme energy density formalism, we investigate the role of surface corrections on the fusion of colliding nuclei. For this, the coefficient of surface correction was varied between 1/36 and 4/36, and its impact was studied on about 180 reactions. Our detailed investigations indicate a linear relationship between the fusion barrier heights and strength of the surface corrections. Our analysis of the fusion barriers advocate the strength of surface correction of 1/36.

Ishwar Dutt; Narinder K. Dhiman

2010-11-19T23:59:59.000Z

37

A combined Event-Driven/Time-Driven molecular dynamics algorithm for the simulation of shock waves in rarefied gases  

Science Conference Proceedings (OSTI)

A novel combined Event-Driven/Time-Driven (ED/TD) algorithm to speed-up the Molecular Dynamics simulation of rarefied gases using realistic spherically symmetric soft potentials is presented. Due to the low density regime, the proposed method correctly ... Keywords: 47.11.Mn, 47.40.Ki, 47.45.-n, 47.61.Cb, Event-Driven MD, Molecular Dynamics, Non-continuum effects, Shock Waves

Paolo Valentini; Thomas E. Schwartzentruber

2009-12-01T23:59:59.000Z

38

Millisecond-scale molecular dynamics simulations on Anton  

Science Conference Proceedings (OSTI)

Anton is a recently completed special-purpose supercomputer designed for molecular dynamics (MD) simulations of biomolecular systems. The machine's specialized hardware dramatically increases the speed of MD calculations, making possible for the first ...

David E. Shaw; Ron O. Dror; John K. Salmon; J. P. Grossman; Kenneth M. Mackenzie; Joseph A. Bank; Cliff Young; Martin M. Deneroff; Brannon Batson; Kevin J. Bowers; Edmond Chow; Michael P. Eastwood; Douglas J. Ierardi; John L. Klepeis; Jeffrey S. Kuskin; Richard H. Larson; Kresten Lindorff-Larsen; Paul Maragakis; Mark A. Moraes; Stefano Piana; Yibing Shan; Brian Towles

2009-11-01T23:59:59.000Z

39

NAMD - The Engine for Large-Scale Classical MD Simulations of Biomolecular  

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

NAMD NAMD NAMD - The Engine for Large-Scale Classical MD Simulations of Biomolecular Systems Based on a Polarizable Force Field PI Name: Benoit Roux PI Email: roux@uchicago.edu Institution: Argonne National Laboratory & University of Chicago Allocation Program: ESP Allocation Hours at ALCF: 80 Million Year: 2010 to 2013 Research Domain: Biological Sciences Biology, at the atomic and molecular level, is governed by complex interactions involving a large number of key constituents, including water, ions, proteins, nucleic acids, and lipid membranes. The goal of this project is to develop new technologies to simulate virtual models of biomolecular systems with an unprecedented accuracy. Large-scale molecular dynamics (MD) simulations based on atomic models play an increasingly

40

Modelling of the internal dynamics and density in a tens of joules plasma focus device  

Science Conference Proceedings (OSTI)

Using MHD theory, coupled differential equations were generated using a lumped parameter model to describe the internal behaviour of the pinch compression phase in plasma focus discharges. In order to provide these equations with appropriate initial conditions, the modelling of previous phases was included by describing the plasma sheath as planar shockwaves. The equations were solved numerically, and the results were contrasted against experimental measurements performed on the device PF-50J. The model is able to predict satisfactorily the timing and the radial electron density profile at the maximum compression.

Marquez, Ariel [CNEA and Instituto Balseiro, 8402 Bariloche (Argentina); Gonzalez, Jose [INVAP-CONICET and Instituto Balseiro, 8402 Bariloche, Argentina. (Argentina); Tarifeno-Saldivia, Ariel; Pavez, Cristian; Soto, Leopoldo [CCHEN, Comision Chilena de Energia Nuclear, Casilla 188-D, Santiago (Chile); Center for Research and Applications in Plasma Physics and Pulsed Power, P4 (Chile); Clausse, Alejandro [CNEA-CONICET and Universidad Nacional del Centro, 7000 Tandil (Argentina)

2012-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

DOE - Office of Legacy Management -- Armco-Rustless Iron and Steel - MD 03  

Office of Legacy Management (LM)

Armco-Rustless Iron and Steel - MD Armco-Rustless Iron and Steel - MD 03 FUSRAP Considered Sites Site: Armco-Rustless Iron & Steel (MD.03 ) Eliminated from consideration under FUSRAP Designated Name: Not Designated Alternate Name: ARMCO Baltimore Works MD.03-1 Location: Baltimore , Maryland MD.03-2 Evaluation Year: 1987 MD.03-1 Site Operations: Test rolling of uranium billets. MD.03-2 MD.03-3 Site Disposition: Eliminated - Potential for contamination remote due to limited quantity of material and duration of test MD.03-1 Radioactive Materials Handled: Yes Primary Radioactive Materials Handled: Uranium MD.03-2 Radiological Survey(s): Health and safety monitoring conducted during operations MD.03-2 Site Status: Eliminated from consideration under FUSRAP MD.03-1 Also see

42

MD. SAIFUR RAHAMAN 9 Hillhouse Ave., Environmental Engineering Program  

E-Print Network (OSTI)

of Chemical Engineering, Yale University Project: "Environmental implications and applications of engineeredMD. SAIFUR RAHAMAN 9 Hillhouse Ave., Environmental Engineering Program Department of Chemical Crystallization in a Fluidized Bed Reactor: Kinetics, Hydrodynamics and Performance" Supervisor: Professor Donald

Elimelech, Menachem

43

Cove Point, MD Natural Gas Liquefied Natural Gas Imports from...  

Gasoline and Diesel Fuel Update (EIA)

Trinidad and Tobago (Million Cubic Feet) Cove Point, MD Natural Gas Liquefied Natural Gas Imports from Trinidad and Tobago (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug...

44

Cove Point, MD Natural Gas Liquefied Natural Gas Imports from...  

Annual Energy Outlook 2012 (EIA)

Norway (Million Cubic Feet) Cove Point, MD Natural Gas Liquefied Natural Gas Imports from Norway (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011...

45

Cove Point, MD Natural Gas Liquefied Natural Gas Imports from...  

Annual Energy Outlook 2012 (EIA)

Nigeria (Million Cubic Feet) Cove Point, MD Natural Gas Liquefied Natural Gas Imports from Nigeria (Million Cubic Feet) Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2011...

46

Cove Point, MD Natural Gas Liquefied Natural Gas Imports from...  

U.S. Energy Information Administration (EIA) Indexed Site

Algeria (Million Cubic Feet) Cove Point, MD Natural Gas Liquefied Natural Gas Imports from Algeria (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6...

47

Cove Point, MD Natural Gas Liquefied Natural Gas Imports from...  

U.S. Energy Information Administration (EIA) Indexed Site

Egypt (Million Cubic Feet) Cove Point, MD Natural Gas Liquefied Natural Gas Imports from Egypt (Million Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

48

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

49

Interactions between Ether Phospholipids and Cholesterol as Determined by Scattering and Molecular Dynamics Simulations  

SciTech Connect

Cholesterol and ether lipids are ubiquitous in mammalian cell membranes, and their interactions are crucial in ether lipid mediated cholesterol trafficking. We report on cholesterol s molecular interactions with ether lipids as determined using a combination of small-angle neutron and Xray scattering, and all-atom molecular dynamics (MD) simulations. A scattering density profile model for an ether lipid bilayer was developed using MD simulations, which was then used to simultaneously fit the different experimental scattering data. From analysis of the data the various bilayer structural parameters were obtained. Surface area constrained MD simulations were also performed to reproduce the experimental data. This iterative analysis approach resulted in good agreement between the experimental and simulated form factors. The molecular interactions taking place between cholesterol and ether lipids were then determined from the validated MD simulations. We found that in ether membranes cholesterol primarily hydrogen bonds with the lipid headgroup phosphate oxygen, while in their ester membrane counterparts cholesterol hydrogen bonds with the backbone ester carbonyls. This different mode of interaction between ether lipids and cholesterol induces cholesterol to reside closer to the bilayer surface, dehydrating the headgroup s phosphate moiety. Moreover, the three-dimensional lipid chain spatial density distribution around cholesterol indicates anisotropic chain packing, causing cholesterol to tilt. These insights lend a better understanding of ether lipid-mediated cholesterol trafficking and the roles that the different lipid species have in determining the structural and dynamical properties of membrane associated biomolecules.

Pan, Jianjun [ORNL; Cheng, Xiaolin [ORNL; Heberle, Frederick A [ORNL; Mostofian, Barmak [ORNL; Kucerka, Norbert [Canadian Neutron Beam Centre and Comelius University (Slovakia); Drazba, Paul [ORNL; Katsaras, John [ORNL

2012-01-01T23:59:59.000Z

50

Security Standards for the Global Information Grid Gary Buda, Booz Allen & Hamilton, Linthicum, MD 21090  

E-Print Network (OSTI)

, Telcordia Technologies, Morristown, NJ 07960 Chris Kubic, Department of Defense, Ft. Meade, MD, 20755

Lee, Ruby B.

51

TO J. A. QuigUy, M.D. NATIONALLPADCW~  

Office of Legacy Management (LM)

J. A. QuigUy, M.D. J. A. QuigUy, M.D. NATIONALLPADCW~ OF oliI0 Cincbnati 39, Ohio September 23, 1960 TRIP RBPCRT TO PIONRBR DIVISION, BENDIX AVI4TIONC~ ION, DAVBNPQRT, SOWA,oNSEPTEMBR6-9,196O F. J. Klein CENTRAL FILE The purpose of this trip was tot (1) determine if a Bendix ronic energy cleaning system can clean uranium-contaminated drums to the extent of rcduciug the @ha ccmtazuinatiou level belav that required for sale as %oa-contaminatecl** by AEC Manual Chapter 5182-0s UOOO a dMlOO& average and at peak not more than 25,OOO a d~lOOcm2, and (2) observe . the health and safety aspects of the wotk and insure the adequate decontauimtiou of the machinery, tools, equi~t, aud teat area. This waa a wet operation Md the tauk waa not ventilated; hawever, should

52

Performance analysis and optimization of molecular dynamics simulation on Godson-T many-core processor  

Science Conference Proceedings (OSTI)

Molecular dynamics (MD) simulation has broad applications, but its irregular memory-access pattern makes performance optimization a challenge. This paper presents a joint application/architecture study to enhance on-chip parallelism of MD on Godson-T ...

Liu Peng; Aiichiro Nakano; Guangming Tan; Priya Vashishta; Dongrui Fan; Hao Zhang; Rajiv K. Kalia; Fenglong Song

2011-05-01T23:59:59.000Z

53

The evolution of solid density within a thermal explosion II. Dynamic proton radiography of cracking and solid consumption by burning  

Science Conference Proceedings (OSTI)

We report proton transmission images obtained subsequent to the laser assisted thermal ignition of a sample of PBX 9501 (a plastic bonded formulation of the explosive nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)). We describe the laser assisted thermal ignition technique as a means to synchronize a non-linear thermal ignition event while preserving the subsequent post-ignition behavior. We have obtained dynamic proton transmission images at two spatial magnifications and viewed both the radial and transverse axis of a solid cylindrical sample encased in aluminum. Images have been obtained with 3 to 15 {mu}s temporal resolution and approximately 100 {mu}m spatial resolution at the higher magnification. We observe case expansion from very early in the experiment, until case fragmentation. We observe spatially anisotropic features in the transmission which we attribute to cracking in the solid explosive, in agreement with previous measurements conducted on two dimensional samples with optical viewing. Digital analysis of the images also reveals spatially isotropic features which we attribute to the evolution of the loss of density by burning subsequent to thermal ignition.

Smilowitz, L.; Henson, B. F.; Romero, J. J.; Asay, B. W.; Saunders, A.; Merrill, F. E.; Morris, C. L.; Kwiatkowski, K.; Grim, G.; Mariam, F.; Schwartz, C. L.; Hogan, G.; Nedrow, P.; Murray, M. M.; Thompson, T. N.; Espinoza, C.; Lewis, D.; Bainbridge, J.; McNeil, W.; Rightley, P. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); and others

2012-05-15T23:59:59.000Z

54

Medical Scholars (BS/MD) Program Expectations and Requirements  

E-Print Network (OSTI)

Medical Scholars (BS/MD) Program Expectations and Requirements Undergraduate portion semester GPAs lower than 3.5 will trigger an automatic review by the Medical Scholars Committee of the Medical Scholars Committee, to delay their entry to medical school by one year to broaden their education

Fernandez, Eduardo

55

DOE - Office of Legacy Management -- Bendix Corp Frieze Division - MD 0-01  

Office of Legacy Management (LM)

Bendix Corp Frieze Division - MD Bendix Corp Frieze Division - MD 0-01 FUSRAP Considered Sites Site: BENDIX CORP., FRIEZE DIVISION (MD.0-01 ) Eliminated from further consideration under FUSRAP Designated Name: Not Designated Alternate Name: None Location: Baltimore , Maryland MD.0-01-1 Evaluation Year: 1987 MD.0-01-3 Site Operations: Produced "classified units" believed to be electronics components - no radioactive materials involved. MD.0-01-1 MD.0-01-3 Site Disposition: Eliminated - No radioactive materials handled at this site MD.0-01-3 Radioactive Materials Handled: No Primary Radioactive Materials Handled: None MD.0-01-3 Radiological Survey(s): No Site Status: Eliminated from further consideration under FUSRAP Also see Documents Related to BENDIX CORP., FRIEZE DIVISION

56

DOE - Office of Legacy Management -- Naval Ordnance Laboratory - MD 0-03  

Office of Legacy Management (LM)

Ordnance Laboratory - MD 0-03 Ordnance Laboratory - MD 0-03 FUSRAP Considered Sites Site: NAVAL ORDNANCE LABORATORY (MD.0-03 ) Eliminated from further consideration under FUSRAP - Referred to DOD Designated Name: Not Designated Alternate Name: Naval Ordnance Laboratory - White Oak Location: White Oak Area , Silver Spring , Maryland MD.0-03-1 MD.0-03-2 Evaluation Year: 1987 MD.0-03-2 Site Operations: Research and development - may have involved radioactive materials because the site was identified on a 1955 Accountability Station List. MD.0-03-1 Site Disposition: Eliminated - NRC licensed MD.0-03-2 Radioactive Materials Handled: None Specifically Identified Primary Radioactive Materials Handled: None specifically indicated Radiological Survey(s): None Indicated Site Status: Eliminated from further consideration under FUSRAP - Referred to DOD MD.0-03-2

57

Spectroscopic studies beyond N = 152 neutron gap : decay of {sup 255 ovr sub 101}Md and {sup 256 ovr sub 101}Md.  

Science Conference Proceedings (OSTI)

The isotopes {sup 255}Md and {sup 256}Md were produced by the irradiation of {sup 253}Es with 35-45 MeV {alpha} particles by ({alpha},n) and ({alpha},2n) reactions and were removed from the target by a helium jet system. {alpha}, {gamma}, and {alpha}-{gamma} coincidence spectra were measured with Si and Ge(Li) detectors. From the EC decays of {sup 255}Md and {sup 256}Md, levels in {sup 255}Fm and {sup 256}Fm were deduced. Favored {alpha} decay of {sup 255}Md was found to populate the 7/2{sup -}[514] single-particle state in {sup 251}Es, thus establishing the 7/2{sup -}[514] as the {sup 255}Md ground state. Several {gamma} rays were observed in the {sub 256}Md {alpha}-{gamma} coincidence spectrum. {sup 256}Fm is the heaviest nucleus in which excited intrinsic states have been identified.

Ahmad, I.; Chasman, R. R.; Fields, P. R.

2000-01-01T23:59:59.000Z

58

Spectroscopic studies beyond the N=152 neutron gap: Decay of {sub 101}{sup 255}Md and {sub 101}{sup 256}Md  

Science Conference Proceedings (OSTI)

The isotopes {sup 255}Md and {sup 256}Md were produced by the irradiation of {sup 253}Es with 35-45 MeV {alpha} particles by ({alpha},n) and ({alpha},2n) reactions and were removed from the target by a helium jet system. {alpha}, {gamma}, and {alpha}-{gamma} coincidence spectra were measured with Si and Ge(Li) detectors. From the EC decays of {sup 255}Md and {sup 256}Md, levels in {sup 255}Fm and {sup 256}Fm were deduced. Favored {alpha} decay of {sup 255}Md was found to populate the 7/2{sup -}[514] single-particle state in {sup 251}Es, thus establishing the 7/2{sup -}[514] as the {sup 255}Md ground state. Several {gamma} rays were observed in the {sup 256}Md {alpha}-{gamma} coincidence spectrum. {sup 256}Fm is the heaviest nucleus in which excited intrinsic states have been identified. (c) 2000 The American Physical Society.

Ahmad, I. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Chasman, R. R. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Fields, P. R. [Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2000-04-01T23:59:59.000Z

59

Coupled-channels density-matrix approach to low-energy nuclear collision dynamics: A technique for quantifying quantum decoherence effects on reaction observables  

E-Print Network (OSTI)

The coupled-channels density-matrix technique for nuclear reaction dynamics, which is based on the Liouville-von Neumann equation with Lindblad dissipative terms, is developed with the inclusion of full angular momentum couplings. It allows a quantitative study of the role and importance of quantum decoherence in nuclear scattering. Formulae of asymptotic observables that can reveal effects of quantum decoherence are given. A method for extracting energy-resolved scattering information from the time-dependent density matrix is introduced. As an example, model calculations are carried out for the low-energy collision of the $^{16}$O projectile on the $^{154}$Sm target.

Alexis Diaz-Torres

2010-10-18T23:59:59.000Z

60

Upper limit on the gas density in the Beta-Pictoris system: On the effect of gas drag on the dust dynamics  

E-Print Network (OSTI)

We investigate in this paper the effect of gas drag on the dynamics of the dust particles in the edge-on Beta-Pictoris disc in order to derive an upper limit on the mass of gas in this system. Our study is motivated by the large uncertainties on the amount of gas in the Beta-Pictoris disc currently found in the literature. The dust particles are assumed to originate from a colliding annulus of planetesimals peaked around 100AU from the central star as proposed by Augereau et al.(2001). We consider the various gas densities that have been inferred from independent observing techniques and we discuss their impact on the dust dynamics and on the disc profile in scattered light along the midplane. We show that the observed scattered light profile of the disc cannot be properly reproduced if hydrogen gas number density at 117AU exceeds 10**4 cm**-3. This corresponds to an upper limit on the total gas mass of about 0.4 Mearth assuming the gas density profile inferred by Brandeker et al.(2004) and thus to a gas to dust mass ratio smaller than 1. Our approach therefore provides an independent diagnostic for a gas depletion in the Beta-Pictoris system relative to the dust disc. Such an approach could also be used to constrain the gas content of recently identified systems like the edge-on disc around AUmic.

P. Thebault; J. -C Augereau

2005-02-22T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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.


61

Charge transport through bio-molecular wires in a solvent: Bridging molecular dynamics and model Hamiltonian approaches  

E-Print Network (OSTI)

We present a hybrid method based on a combination of quantum/classical molecular dynamics (MD) simulations and a mod el Hamiltonian approach to describe charge transport through bio-molecular wires with variable lengths in presence o f a solvent. The core of our approach consists in a mapping of the bio-molecular electronic structure, as obtained f rom density-functional based tight-binding calculations of molecular structures along MD trajectories, onto a low di mensional model Hamiltonian including the coupling to a dissipative bosonic environment. The latter encodes fluctuat ion effects arising from the solvent and from the molecular conformational dynamics. We apply this approach to the c ase of pG-pC and pA-pT DNA oligomers as paradigmatic cases and show that the DNA conformational fluctuations are essential in determining and supporting charge transport.

R. Gutierrez; R. Caetano; P. B. Woiczikowski; T. Kubar; M. Elstner; G. Cuniberti

2009-01-22T23:59:59.000Z

62

Oral Histories: Oncologist Helen Vodopick, M.D.  

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

2 2 HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Oncologist Helen Vodopick, M.D. Conducted December 28, 1994 United States Department of Energy Office of Human Radiation Experiments August 1995 CONTENTS Foreword Short Biography Academic Fellowship at Oak Ridge Institute for Nuclear Studies (ORINS), 1960 Appointment to the Staff at ORINS Medical Division The Medium-Exposure-Rate Total Body Irradiator (METBI) ORINS Radioisotope Tracer Studies Participation by Regional Universities at Oak Ridge Associated Universities (ORAU) Treatment of Cancer Patients with the METBI Introduction of Immunotherapy Radiation Treatment for Leukemia Patients Bone Marrow Treatment of Leukemia Low-Exposure-Rate Total Body Irradiator (LETBI) Treatment of Radiation Accident Victims at ORAU

63

Substructured multibody molecular dynamics.  

SciTech Connect

We have enhanced our parallel molecular dynamics (MD) simulation software LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator, lammps.sandia.gov) to include many new features for accelerated simulation including articulated rigid body dynamics via coupling to the Rensselaer Polytechnic Institute code POEMS (Parallelizable Open-source Efficient Multibody Software). We use new features of the LAMMPS software package to investigate rhodopsin photoisomerization, and water model surface tension and capillary waves at the vapor-liquid interface. Finally, we motivate the recipes of MD for practitioners and researchers in numerical analysis and computational mechanics.

Grest, Gary Stephen; Stevens, Mark Jackson; Plimpton, Steven James; Woolf, Thomas B. (Johns Hopkins University, Baltimore, MD); Lehoucq, Richard B.; Crozier, Paul Stewart; Ismail, Ahmed E.; Mukherjee, Rudranarayan M. (Rensselaer Polytechnic Institute, Troy, NY); Draganescu, Andrei I.

2006-11-01T23:59:59.000Z

64

Soham Al Snih Al Snih, MD., PhD. Curriculum Vitae CURRICULUM VITAE  

E-Print Network (OSTI)

Soham Al Snih Al Snih, MD., PhD. Curriculum Vitae 1 CURRICULUM VITAE NAME: Soham Al Snih Al Snih, M at the Sealy Center on Aging, University of Texas Medical Branch, Galveston, TX. #12;Soham Al Snih Al Snih, MD arthritis. B. Grant Support Current Grant Support: 1R03 AG029959-01A2 (Al Snih ­PI) Period: 06

Wood, James B.

65

Density Dependence of the Mass Function of Globular Star Clusters in the Sombrero Galaxy and its Dynamical Implications  

E-Print Network (OSTI)

We have constructed the mass function of globular star clusters in the Sombrero galaxy in bins of different internal half-mass density rho_h and projected galactocentric distance R. This is based on the published measurements of the magnitudes and effective radii of the clusters by Spitler et al. (2006) in BVR images taken with the ACS on HST. We find that the peak of the mass function M_p increases with rho_h by a factor of about 4 but remains nearly constant with R. Our results are almost identical to those presented recently by McLaughlin & Fall (2007) for globular clusters in the Milky Way. The mass functions in both galaxies agree with a simple, approximate model in which the clusters form with a Schechter initial mass function and evolve subsequently by stellar escape driven by internal two-body relaxation. These findings therefore undermine recent claims that the present peak of the mass function of globular clusters must have been built into the initial conditions.

Rupali Chandar; S. Michael Fall; Dean E. McLaughlin

2007-09-10T23:59:59.000Z

66

EA-1942: Cove Point Liquefaction Project, Lusby, MD | Department of Energy  

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

2: Cove Point Liquefaction Project, Lusby, MD 2: Cove Point Liquefaction Project, Lusby, MD EA-1942: Cove Point Liquefaction Project, Lusby, MD SUMMARY The Federal Energy Regulatory Commission (FERC) is preparing, with DOE as a cooperating agency, an EA, to analyze the potential environmental impacts of a proposal to add natural gas liquefaction and exportation capabilities to an existing Cove Point LNG Terminal located on the Chesapeake Bay in Lusby, Maryland. PUBLIC COMMENT OPPORTUNITIES None available at this time. DOCUMENTS AVAILABLE FOR DOWNLOAD September 28, 2012 EA-1942: Notice of Intent to Prepare an Environmental Assessment Cove Point Liquefaction Project, Lusby, MD September 24, 2012 EA-1942: Notice of Intent of to Prepare an Environmental Assessment Cove Point Liquefaction Project, Lusby, MD

67

Molecular Dynamics Simulations on High-Performance Reconfigurable Computing Systems  

Science Conference Proceedings (OSTI)

The acceleration of molecular dynamics (MD) simulations using high-performance reconfigurable computing (HPRC) has been much studied. Given the intense competition from multicore and GPUs, there is now a question whether MD on HPRC can be competitive. ... Keywords: FPGA-based coprocessors, application acceleration, bioinformatics, biological sequence alignment, high performance reconfigurable computing

Matt Chiu; Martin C. Herbordt

2010-11-01T23:59:59.000Z

68

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

69

BERAC Meeting, October 6-7, 2011, Rockville, MD| U.S. DOE Office of Science  

Office of Science (SC) Website

Meeting, October 6-7, 2011, Rockville, MD Meeting, October 6-7, 2011, Rockville, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting, October 6-7, 2011, Rockville, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting October 6-7, 2011 Rockville, MD Agenda .docx file (13KB) Presentations Sharlene Weatherwax, State of BER Report .pptx file (2.0MB) Gary Geernaert, Climate and Environmental Sciences Division Update .pptx file (24.0MB) Todd Anderson, Biological Systems Science Division Update .pptx file (8.0MB) Susan Hubbard, Science Talk - Geophysical Signatures of Subsurface Microbially-Mediated Processes: Toward Quantification of In-Situ Ecosystem

70

BERAC Meeting October 16, 2006 North Bethesda, MD | U.S. DOE Office of  

Office of Science (SC) Website

October 16, 2006 North Bethesda, MD October 16, 2006 North Bethesda, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting October 16, 2006 North Bethesda, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting October 16, 2006 North Bethesda, MD Agenda .pdf file (8KB) Presentations Jerry Elwood .ppt file (4.1MB), State of BER James Ehleringer .ppt file (6.7MB), Report on BERAC Review of FACE Experiments David Kingsbury .ppt file (10.4MB), CAMERA-Metagenomics meets the Cyberinfrastructure Chris Somerville .ppt file (59KB), Life Sciences PART Measure Progress Report Joyce Penner .ppt file (116KB), Climate Change Science PART Measure

71

BERAC Meeting February 18 - 19, 2009 North Bethesda, MD | U.S. DOE Office  

Office of Science (SC) Website

18 - 19, 2009 North Bethesda, MD 18 - 19, 2009 North Bethesda, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting February 18 - 19, 2009 North Bethesda, MD Print Text Size: A A A RSS Feeds FeedbackShare Page Biological and Environmental Research Advisory Committee Meeting February 18-19, 2009 North Bethesda, MD Meeting Agenda .pdf file (9KB) Presentations Anna Palmisano .ppt file (11.7MB), State of BER Sharlene Weatherwax .ppt file (8.7MB), Biological Systems Science Division Update Wanda Ferrell .ppt file (16.9MB), Climate and Environmental Sciences Division Update Jeff Amthor, Report on the Climate Change Research Strategic Plan

72

BERAC Meeting February 23-24, 2010 Gaithersburg, MD | U.S. DOE Office of  

Office of Science (SC) Website

February 23-24, 2010 Gaithersburg, MD February 23-24, 2010 Gaithersburg, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting February 23-24, 2010 Gaithersburg, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting February 23-24,2010 Gaithersburg MD Agenda .pdf file (8KB) Presentations Patricia Dehmer .ppt file (7.4MB), News from the Office of Science Anna Palmisano .ppt file (18.0MB), State of BER Jeff Marqusee .ppt file (5.0MB), SERDP & ESTCP Phil Robertson .pdf file (3.1MB), Bioenergy & Sustainability (pdf format) Wanda Ferrell .ppt file (5.1MB), Climate and Environmental Sciences Division Update

73

BERAC Meeting September 1-2, 2009 Gaithersburg, MD | U.S. DOE Office of  

Office of Science (SC) Website

-2, 2009 Gaithersburg, MD -2, 2009 Gaithersburg, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting September 1-2, 2009 Gaithersburg, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting September 1-2, 2009 Gaithersburg, MD Agenda .pdf file (8KB) Presentations Patricia Dehmer .ppt file (25.0MB), News from the Office of Science Anna Palmisano .pptx file (6.6MB), State of BER Barbara Alving, NIH .ppt file (6.6MB), Connecting the Nation's Researchers, Patients and Communities: Next Steps Horst Simon .pdf file (2.6MB), Future Trends in Computing Sharlene Weatherwax .pdf file (928KB), Biological Systems Science

74

BERAC Meeting May 19-20, 2008 Hilton Hotel Gaithersburg, MD | U.S. DOE  

Office of Science (SC) Website

9-20, 2008 Hilton Hotel Gaithersburg, MD 9-20, 2008 Hilton Hotel Gaithersburg, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting May 19-20, 2008 Hilton Hotel Gaithersburg, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting May 19-20, 2008 Hilton Hotel Gaithersburg, MD Agenda .pdf file (17KB) Presentations Mike Hochella .ppt file (388KB), Environmental Remediation Sciences Division Committee of Visitors Report Jim Adelstein .ppt file (1.1MB), Report on the Low Dose Radiation Research Program Himadri Pakrasi .ppt file (22.3MB), Science Talk, Membrane Biology Grand Challenge Jeff Amthor .ppt file (11.7MB), Update on BER Program for Ecosystems

75

BERAC Meeting, June 6-7, 2012 Gaithersburg, MD| U.S. DOE Office of Science  

Office of Science (SC) Website

June 6-7, 2012 Gaithersburg, MD June 6-7, 2012 Gaithersburg, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting, June 6-7, 2012 Gaithersburg, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting June 6-7, 2012 Gaithersburg, MD Agenda .pdf file (424KB) Presentations Sharlene Weatherwax, BER Associate Director State of BER Report .pdf file (482KB) Todd Anderson, Director, Biological Systems Science Division Biological Systems Science Division Update .pdf file (1.9MB) Gary Geernaert, Director, Climate and Environmental Sciences Division Climate and Environmental Sciences Division Update .pdf file (1.6MB) Jonathan Petters,

76

BERAC Meeting, February 21-22, 2013, Rockville, MD | U.S. DOE Office of  

Office of Science (SC) Website

February 21-22, 2013 BERAC Rockville, MD February 21-22, 2013 BERAC Rockville, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings February 21-22, 2013 BERAC Rockville, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting, February 21-22, 2013, Rockville, MD Agenda .pdf file (10KB) Presentations: Sharlene Weatherwax .pdf file (1.9MB) - Office of Biological and Environmental Research Update Todd Anderson .pdf file (1.7MB) - Biological Systems Science Division Update Gary Geernaert .pdf file (2.3MB) - Climate and Environmental Sciences Division Update Judy Wall .pdf file (3.5MB) - The Genetic Basis for Bacterial Mercury Methylation

77

BERAC Meeting May 14-15, 2007 North Bethesda, MD | U.S. DOE Office of  

Office of Science (SC) Website

4-15, 2007 North Bethesda, MD 4-15, 2007 North Bethesda, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting May 14-15, 2007 North Bethesda, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting May 14-15, 2007 North Bethesda, MD Agenda .pdf file (10KB) Presentations Joyce Penner .ppt file (74KB), Report on ARM Facilities Charge William Pizer .pdf file (292KB), Report on Integrated Assessment Charge John Ferrell .ppt file (2.7MB), Report on DOE Energy Efficiency and Renewable Energy Biomass Program Paul Vaska .ppt file (23.6MB), Science Talk, Advances in Instrumentation for Small-Animal PET Imaging Mike Viola .ppt file (2.3MB), State of BER

78

BERAC Meeting September 16-17, 2010 Gaithersburg, MD | U.S. DOE Office of  

Office of Science (SC) Website

6-17, 2010 Gaithersburg, MD 6-17, 2010 Gaithersburg, MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting September 16-17, 2010 Gaithersburg, MD Print Text Size: A A A RSS Feeds FeedbackShare Page BERAC Meeting September 16-17, 2010 Gaithersburg, MD Agenda .pdf file (8KB) Presentations Anna Palmisano .pptx file (6.5MB), State of BER Judy Wall .pptx file (904KB), CESD COV Report Gary Sayler .ppt file (65.0MB), Science Lecture, "From Microbes to Man: Environmental Biosensing with Bacterial Bioluminescence" Gary Geernaert .pptx file (4.5MB), Climate and Environmental Sciences Division Update Sharlene Weatherwax .pptx file (5.6MB), Biological Systems Science

79

Price of Cove Point, MD Natural Gas LNG Imports from Algeria...  

Gasoline and Diesel Fuel Update (EIA)

Algeria (Dollars per Thousand Cubic Feet) Price of Cove Point, MD Natural Gas LNG Imports from Algeria (Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

80

Price of Cove Point, MD Natural Gas LNG Total Imports (Dollars...  

Gasoline and Diesel Fuel Update (EIA)

Total Imports (Dollars per Thousand Cubic Feet) Price of Cove Point, MD Natural Gas LNG Total Imports (Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 Year-2 Year-3 Year-4...

Note: This page contains sample records for the topic "dynamics md density" 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

Price of Cove Point, MD Natural Gas LNG Imports from Egypt (Nominal...  

U.S. Energy Information Administration (EIA) Indexed Site

Egypt (Nominal Dollars per Thousand Cubic Feet) Price of Cove Point, MD Natural Gas LNG Imports from Egypt (Nominal Dollars per Thousand Cubic Feet) Decade Year-0 Year-1 Year-2...

82

Adaptive-boost molecular dynamics simulation of carbon diffusion in iron  

E-Print Network (OSTI)

We have developed an accelerated molecular dynamics (MD) method to model atomic-scale rare events. In this method, a smooth histogram of collective variables is first estimated by canonical ensemble molecular dynamics ...

Ishii, Akio

83

Molecular dynamics simulation of displacement cascades in FeCr alloys  

E-Print Network (OSTI)

Molecular dynamics simulation of displacement cascades in Fe­Cr alloys L. Malerba a,*, D. Terentyev by displacement cascades in the relevant material. Molecular dynamics (MD) is well known to be the simulation tool

84

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

85

LDRD Final Report (08-ERD-037): Important Modes to Drive Protein MD Simulations to the Next Conformational Level  

SciTech Connect

Every action in biology is performed by dynamic proteins that convert between multiple states in order to engage their functions. Often binding to various ligands is essential for the rates of desired transitions to be enhanced. The goal of computational biology is to study these transitions and discover the different states to fully understand the protein's normal and diseased function, design drugs to target/bias specific states, and understand all of the interactions in between. We have developed a new methodology that is capable of calculating the absolute free energy of proteins while taking into account all the interactions with the solvent molecules. The efficiency of the new scheme is an order of magnitude greater than any existing technique. This method is now implemented in the massively parallel popular MD program package NAMD. This now makes it possible to calculate the relative stability of different conformational states of biological macromolecules as well as their binding free energies to various ligands.

Sadigh, B

2011-04-07T23:59:59.000Z

86

Molecular dynamics simulation of Li surface erosion and bubble formation  

E-Print Network (OSTI)

Molecular dynamics simulation of Li surface erosion and bubble formation Z. Insepov *, A. Hassanein Structure and dynamical properties of liquid Li containing He atoms were studied by the Molecular Dynamics devices. Molecular dynamics (MD) method is capable of studying important collision processes and providing

Harilal, S. S.

87

Anton, a special-purpose machine for molecular dynamics simulation  

Science Conference Proceedings (OSTI)

The ability to perform long, accurate molecular dynamics (MD) simulations involving proteins and other biological macro-molecules could in principle provide answers to some of the most important currently outstanding questions in the fields of biology, ...

David E. Shaw; Martin M. Deneroff; Ron O. Dror; Jeffrey S. Kuskin; Richard H. Larson; John K. Salmon; Cliff Young; Brannon Batson; Kevin J. Bowers; Jack C. Chao; Michael P. Eastwood; Joseph Gagliardo; J. P. Grossman; C. Richard Ho; Douglas J. Ierardi; István Kolossváry; John L. Klepeis; Timothy Layman; Christine McLeavey; Mark A. Moraes; Rolf Mueller; Edward C. Priest; Yibing Shan; Jochen Spengler; Michael Theobald; Brian Towles; Stanley C. Wang

2008-07-01T23:59:59.000Z

88

A scalable parallel algorithm for dynamic range-limited n-tuple computation in many-body molecular dynamics simulation  

Science Conference Proceedings (OSTI)

Recent advancements in reactive molecular dynamics (MD) simulations based on many-body interatomic potentials necessitate efficient dynamic n-tuple computation, where a set of atomic n-tuples within a given spatial range is constructed ... Keywords: dynamic range-limited n-tuple computation, molecular dynamics, parallel computing

Manaschai Kunaseth, Rajiv K. Kalia, Aiichiro Nakano, Ken-ichi Nomura, Priya Vashishta

2013-11-01T23:59:59.000Z

89

Bayesian uncertainty quantification and propagation in molecular dynamics simulations: A high performance computing framework  

Science Conference Proceedings (OSTI)

We present a Bayesian probabilistic framework for quantifying and propagating the uncertainties in the parameters of force fields employed in molecular dynamics (MD) simulations. We propose a highly parallel implementation of the transitional Markov chain Monte Carlo for populating the posterior probability distribution of the MD force-field parameters. Efficient scheduling algorithms are proposed to handle the MD model runs and to distribute the computations in clusters with heterogeneous architectures. Furthermore

Panagiotis Angelikopoulos; Costas Papadimitriou; Petros Koumoutsakos

2012-01-01T23:59:59.000Z

90

Density functional theory study of the structural, electronic, lattice dynamical, and thermodynamic properties of Li4SiO4 and its capability for CO2 capture  

SciTech Connect

The structural, electronic, lattice dynamical, optical, thermodynamic, and CO{sub 2} capture properties of monoclinic and triclinic phases of Li{sub 4}SiO{sub 4} are investigated by combining density functional theory with phonon lattice dynamics calculations. We found that these two phases have some similarities in their bulk and thermodynamic properties. The calculated bulk modulus and the cohesive energies of these two phases are close to each other. Although both of them are insulators, the monoclinic phase of Li{sub 4}SiO{sub 4} has a direct band gap of 5.24 eV while the triclinic Li{sub 4}SiO{sub 4} phase has an indirect band gap of 4.98 eV. In both phases of Li{sub 4}SiO{sub 4}, the s orbital of O mainly contributes to the lower-energy second valence band (VB{sub 2}) and the p orbitals contribute to the fist valence band (VB{sub 1}) and the conduction bands (CBs). The s orbital of Si mainly contributes to the lower portions of the VB1 and VB{sub 2}, and Si p orbitals mainly contribute to the higher portions of the VB{sub 1} and VB{sub 2}. The s and p orbitals of Li contribute to both VBs and to CBs, and Li p orbitals have a higher contribution than the Li s orbital. There is possibly a phonon soft mode existing in triclinic {gamma}-Li{sub 4}SiO{sub 4}; in the monoclinic Li{sub 4}SiO{sub 4}, there are three phonon soft modes, which correspond to the one type of Li disordered over a few sites. Their LO-TO splitting indicates that both phases of Li{sub 4}SiO{sub 4} are polar anisotropic materials. The calculated infrared absorption spectra for LO and TO modes are different for these two phases of Li{sub 4}SiO{sub 4}. The calculated relationships of the chemical potential versus temperature and CO{sub 2} pressure for reaction of Li{sub 4}SiO{sub 4} with CO{sub 2} shows that Li{sub 4}SiO{sub 4} could be a good candidate for a high-temperature CO{sub 2} sorbent while used for postcombustion capture technology.

Duan, Yuhua; Parlinski, K.

2011-01-01T23:59:59.000Z

91

Molecular Dynamics Simulations of Heat Transfer In Nanoscale Liquid Films  

E-Print Network (OSTI)

Molecular Dynamics (MD) simulations of nano-scale flows typically utilize fixed lattice crystal interactions between the fluid and stationary wall molecules. This approach cannot properly model thermal interactions at the wall-fluid interface. In order to properly simulate the flow and heat transfer in nano-scale channels, an interactive thermal wall model is developed. Using this model, the Fourier’s law of heat conduction is verified in a 3.24 nm height channel, where linear temperature profiles with constant thermal conductivity is obtained. The thermal conductivity is verified using the predictions of Green-Kubo theory. MD simulations at different wall wettability ( ??f /? ) and crystal bonding stiffness values (K) have shown temperature jumps at the liquid/solid interface, corresponding to the well known Kapitza resistance. Using systematic studies, the thermal resistance length at the interface is characterized as a function of the surface wettability, thermal oscillation frequency, wall temperature and thermal gradient. An empirical model for the thermal resistance length, which could be used as the jump-coefficient of a Navier boundary condition, is developed. Temperature distributions in the nano-channels are predicted using analytical solution of the continuum heat conduction equation subjected to the new temperature jump condition, and validated using the MD results. Momentum and heat transfer in shear driven nanochannel flows are also investigated. Work done by the viscous stresses heats the fluid, which is dissipated through the channel walls, maintained at isothermal conditions. Spatial variations in the fluid density, kinematic viscosity, shear- and energy dissipation rates are presented. The energy dissipation rate is almost a constant for ??f /? < 0.6, which results in parabolic temperature profiles in the domain with temperature jumps due to the Kapitza resistance at the liquid/solid interfaces. Using the energy dissipation rates predicted by MD simulations and the continuum energy equation subjected to the temperature jump boundary conditions developed in this study, the analytical solutions are obtained for the temperature profiles, which agree well with the MD results.

Kim, Bo Hung

2009-05-01T23:59:59.000Z

92

BERAC Meeting September 5 2008 Gaithersburg MD | U.S. DOE Office of Science  

Office of Science (SC) Website

September 5 2008 Gaithersburg MD September 5 2008 Gaithersburg MD Biological and Environmental Research Advisory Committee (BERAC) BERAC Home Meetings BERAC Minutes BERAC Minutes Archive Members Charges/Reports Charter .pdf file (40KB) BER Committees of Visitors BER Home Meetings BERAC Meeting September 5 2008 Gaithersburg MD Print Text Size: A A A RSS Feeds FeedbackShare Page BER September 5, 2008 Arlington, VA Agenda Presentations Peg Riley .ppt file (357KB), Life and Medical Sciences Division Committee of Visitors Report Patricia Dehmer .ppt file (2.6MB), Report from the Office of Science Todd Anderson .ppt file (1.2MB), Scientific Focus Area (SFA) Rollout & Discussion Robert Dickinson .ppt file (6.1MB), Report on Climate Research Grand Challenges Mike Kuperberg .ppt file (975KB), Climate & Environmental Sciences

93

Molecular Dynamics Simulation of Macromolecules Using Graphics Processing Unit  

E-Print Network (OSTI)

Molecular dynamics (MD) simulation is a powerful computational tool to study the behavior of macromolecular systems. But many simulations of this field are limited in spatial or temporal scale by the available computational resource. In recent years, graphics processing unit (GPU) provides unprecedented computational power for scientific applications. Many MD algorithms suit with the multithread nature of GPU. In this paper, MD algorithms for macromolecular systems that run entirely on GPU are presented. Compared to the MD simulation with free software GROMACS on a single CPU core, our codes achieve about 10 times speed-up on a single GPU. For validation, we have performed MD simulations of polymer crystallization on GPU, and the results observed perfectly agree with computations on CPU. Therefore, our single GPU codes have already provided an inexpensive alternative for macromolecular simulations on traditional CPU clusters and they can also be used as a basis to develop parallel GPU programs to further speedup the computations.

Ji Xu; Ying Ren; Wei Ge; Xiang Yu; Xiaozhen Yang; Jinghai Li

2010-01-21T23:59:59.000Z

94

Molecular dynamics simulations of ordered alkane chains physisorbed on graphite  

E-Print Network (OSTI)

Molecular dynamics simulations of ordered alkane chains physisorbed on graphite Reinhard Hentschke molecular axes oriented parallel to the substrate. Here we employ molecular dynamics (MD) simulations to obtain more details on the molecular order and dynamics within the alkane lamellae as a function

Peters, Achim

95

Molecular Dynamics Simulations of Temperature Equilibration in Dense Hydrogen  

DOE Green Energy (OSTI)

The temperature equilibration rate in dense hydrogen (for both T{sub i} > T{sub e} and T{sub i} < T{sub e}) has been calculated with large-scale molecular dynamics simulations for temperatures between 10 and 300 eV and densities between 10{sup 20}/cc to 10{sup 24}/cc. Careful attention has been devoted to convergence of the simulations, including the role of semiclassical potentials. We find that for Coulomb logarithms L {approx}> 1, Brown-Preston-Singleton [Brown et al., Phys. Rep. 410, 237 (2005)] with the sub-leading corrections and the fit of Gericke-Murillo-Schlanges [Gericke et al., PRE 65, 036418 (2003)] to the T-matrix evaluation of the collision operator, agrees with the MD data to within the error bars of the simulation. For more strongly-coupled plasmas where L {approx}< 1, our numerical results are consistent with the fit of Gericke-Murillo-Schlanges.

Glosli, J; Graziani, F; More, R; Murillo, M; Streitz, F; Surh, M; Benedict, L; Hau-Riege, S; Langdon, A; London, R

2008-02-14T23:59:59.000Z

96

Molecular dynamics simulation of hydrogen diffusion in titanium  

National Nuclear Security Administration (NNSA)

9: Computation Physics 9: Computation Physics Atomistic Simulation of Hydrogen Diffusion in Titanium. Alexandr S. Rokhmanenkov, Alexey Yu. Kuksin, and Vladimir V. Stegailov All-Russia Research Institute of Automatics, Moscow 125412, Russia rohmanenkov@gmail.com Summary Study of the behavior of hydrogen in metals and alloys. The study is based on classical molecular dynamics (MD) and density functional theory (DFT) calculations. Study of the behavior of hydrogen in metals and alloys is of great importance due to the practical uses of hydrogen-metal systems for absorption of nuclear radiation, in neutron sources, for storage of hydrogen, or as catalyzers. This work is devoted to atomistic simulation of hydrogen diffusion in titanium hydrides and the effect of stresses and lattice defects on diffusivity.

97

Mar. Drugs 2013, 11, 3350-3371; doi:10.3390/md11093350 marine drugs  

E-Print Network (OSTI)

Mar. Drugs 2013, 11, 3350-3371; doi:10.3390/md11093350 marine drugs ISSN 1660-3397 www% cytotoxicity was observed at the highest concentration tested (5 µg mL-1 ). However, OPEN ACCESS #12;Mar. Drugs Pinna had first been implicated in food poisoning in China in 1990 [1]. Pinnatoxin A (Pn

Recanati, Catherine

98

A coupled RISM/MD or MC simulation methodology for solvation free energies  

E-Print Network (OSTI)

A coupled RISM/MD or MC simulation methodology for solvation free energies Holly Freedman, Thanh N methods for determination of solvation free energies. We employ the RISM formulation of solvation free-netted chain equations. We apply this approach to determining free energies of solvation for several small

Truong, Thanh N.

99

MD Study of Phase Change of Water inside a Carbon Nanotube Tatsuto KIMURA and Shigeo MARUYAMA  

E-Print Network (OSTI)

into ice crystal at 220 K or 200 K. In the case of phase change at 220 K, octagonal ice nanotube MD Study of Phase Change of Water inside a Carbon Nanotube * Tatsuto KIMURA and Shigeo MARUYAMA Dept. of Mech. Eng., The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 Phase change

Maruyama, Shigeo

100

Ira Helfand, MD International Physicians for the Prevention of Nuclear War  

E-Print Network (OSTI)

of studies have shown that a limited, regional nuclear war between India and Pakistan would cause significantIra Helfand, MD International Physicians for the Prevention of Nuclear War Physicians for Social Responsibility NUCLEAR FAMINE: A BILLION PEOPLE AT RISK Global Impacts of Limited Nuclear War on Agriculture

Robock, Alan

Note: This page contains sample records for the topic "dynamics md density" 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

Force Field Development and Molecular Dynamics of [NiFe] Hydrogenase  

Science Conference Proceedings (OSTI)

Classical molecular force-field parameters describing the structure and motion of metal clusters in [NiFe] hydrogenase enzymes can be used to compare the dynamics and thermodynamics of [NiFe] under different oxidation, protonation, and ligation circumstances. Using density functional theory (DFT) calculations of small model clusters representative of the active site and the proximal, medial, and distal Fe/S metal centers and their attached protein side chains, we have calculated classical force-field parameters for [NiFe] in reduced and oxidized states, including internal coordinates, force constants, and atom-centered charges. Derived force constants revealed that cysteinate ligands bound to the metal ions are more flexible in the Ni-B active site, which has a bridging hydroxide ligand, than in the Ni-C active site, which has a bridging hydride. Ten nanosecond all-atom, explicit-solvent MD simulations of [NiFe] hydrogenase in oxidized and reduced catalytic states established the stability of the derived force-field parameters in terms of C{alpha} and metal cluster fluctuations. Average active site structures from the protein MD simulations are consistent with [NiFe] structures from the Protein Data Bank, suggesting that the derived force-field parameters are transferrable to other hydrogenases beyond the structure used for testing. A comparison of experimental H{sub 2}-production rates demonstrated a relationship between cysteinate side chain rotation and activity, justifying the use of a fully dynamic model of [NiFe] metal cluster motion.

Smith, Dayle MA; Xiong, Yijia; Straatsma, TP; Rosso, Kevin M.; Squier, Thomas C.

2012-05-09T23:59:59.000Z

102

Ceramic Composites, Inc. 1110 Benfield Blvd, Ste Q, Millersville, MD 21108  

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

Composites, Inc. Composites, Inc. 1110 Benfield Blvd, Ste Q, Millersville, MD 21108 A subsidiary of Technology Assessment and Transfer, Inc. 410-987-3435 fax 410-987-7172 www.techassess.com AGENCY: DOE / NETL CONTRACT: DE-FG02-03ER83627 TITLE: Enhanced Performance Carbon Foam Heat Exchanger for Power Plant Cooling REPORT: Final Technical Report PERIOD: 21 July 2003 - 13 July 2007 TPOC: Barbara Carney carney@netl.doe.gov PHONE: 304-285-4671 PI: Steven Seghi steve@techassess.com PHONE: 410-987-3435 COMPANY: Ceramic Composites, Inc. 133 Defense Hwy, Ste 212 Annapolis, MD 21401 SBIR/STTR Rights Notice These SBIR/STTR data are furnished with SBIR/STTR rights under Grant No. DE-FG02- 03ER83627. For a period of 4 years after the acceptance of all items to be delivered under this

103

FINDING OF MD SIGNIFICANT IMPACT FORMERLY UTILIZED HED/AEC SITES REMEDIAL ACTION PROGRAM:  

Office of Legacy Management (LM)

FINDING OF MD SIGNIFICANT IMPACT FINDING OF MD SIGNIFICANT IMPACT FORMERLY UTILIZED HED/AEC SITES REMEDIAL ACTION PROGRAM: BAY0 CANYONS, NEW MEXICO Under the Formerly Utilized Sites Remedial Action Program (FUSRAP), the U.S. Department of Energy (DOE) has proposed to carry out rcmedfrl action at a site located in Bayo Canyon, Los Alamos County, New Mexico. Although the site as partially decontaminated and decommissioned in the 196Os, there remain above-background amounts of radionuclides. DOE has determined that strontium-90 in excess of DDE's proposed remedial- action criterir exists in subsurface materials underlying an area of about 0.6 ha (1.5 acres) at the Bayo Canyon site. The proposed action is to demarcate this are8 and restrict its use to activities that will not disturb this sub-

104

Medication Safety in Older Adults: Home-Based Practice Patterns Joshua P. Metlay, MD, PhD,wzz  

E-Print Network (OSTI)

Medication Safety in Older Adults: Home-Based Practice Patterns Joshua P. Metlay, MD, Ph-reported sources of in- formation on current medications as well as home-based practices for organizing medication

Hennessy, Sean

105

Exploiting hierarchical parallelisms for molecular dynamics simulation on multicore clusters  

Science Conference Proceedings (OSTI)

We have developed a scalable hierarchical parallelization scheme for molecular dynamics (MD) simulation on multicore clusters. The scheme explores multilevel parallelism combining: (1) Internode parallelism using spatial decomposition via message passing; ... Keywords: Molecular dynamics simulation, Multicore cluster, Scalable hierarchical parallelization scheme, Single instruction multiple data

Liu Peng; Manaschai Kunaseth; Hikmet Dursun; Ken-Ichi Nomura; Weiqiang Wang; Rajiv K. Kalia; Aiichiro Nakano; Priya Vashishta

2011-07-01T23:59:59.000Z

106

Anton, a special-purpose machine for molecular dynamics simulation  

Science Conference Proceedings (OSTI)

The ability to perform long, accurate molecular dynamics (MD) simulations involving proteins and other biological macro-molecules could in principle provide answers to some of the most important currently outstanding questions in the fields of biology, ... Keywords: bioinformatics, biomolecular system simulation, computational biology, computational drug design, molecular dynamics, protein folding, protein structure, special-purpose machine

David E. Shaw; Martin M. Deneroff; Ron O. Dror; Jeffrey S. Kuskin; Richard H. Larson; John K. Salmon; Cliff Young; Brannon Batson; Kevin J. Bowers; Jack C. Chao; Michael P. Eastwood; Joseph Gagliardo; J. P. Grossman; C. Richard Ho; Douglas J. Ierardi; István Kolossváry; John L. Klepeis; Timothy Layman; Christine McLeavey; Mark A. Moraes; Rolf Mueller; Edward C. Priest; Yibing Shan; Jochen Spengler; Michael Theobald; Brian Towles; Stanley C. Wang

2007-06-01T23:59:59.000Z

107

Molecular Dynamics Simulations of Microscale Fluid Transport  

E-Print Network (OSTI)

Recent advances in micro-science and technology, like Micro-ElectroMechanical Systems (MEMS), have generated a group of unique liquid flow problems that involve characteristic length scales of a micron. Also, in manufacturing processes such as coatings, current continuum models are unable to predict microscale physical phenomena that appear in these nonequilibrium systems. It is suspected that in these systems, molecular-level processes can control the interfacial energy and viscoelastic properties at the liquid/solid boundary. A massively parallel molecular dynamics (MD) code has been developed to better understand microscale transport mechanisms, fluid-structure interactions, and scale effects in micro-domains. Specifically, this MD code has been used to analyze liquid channel flow problems for a variety of channel widths, e.g. 0.005-0.05 microns. This report presents results from MD simulations of Poiseuille flow and Couette flow problems and address both scaling and modeling issues...

C. C. Wong; A. R. Lopez; M.J. Stevens; S. J. Plimpton; Category Uc; Like Micro-electro

1998-01-01T23:59:59.000Z

108

ANL/ALCF/ESP-13/14 NAMD - The Engine for Large-Scale Classical MD  

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

4 4 NAMD - The Engine for Large-Scale Classical MD Simulations of Biomolecular Systems Based on a Polarizable Force Field ALCF-2 Early Science Program Technical Report Argonne Leadership Computing Facility About Argonne National Laboratory Argonne is a U.S. Department of Energy laboratory managed by UChicago Argonne, LLC under contract DE-AC02-06CH11357. The Laboratory's main facility is outside Chicago, at 9700 South Cass Avenue, Argonne, Illinois 60439. For information about Argonne and its pioneering science and technology programs, see www.anl.gov. Availability of This Report This report is available, at no cost, at http://www.osti.gov/bridge. It is also available on paper to the U.S. Department of Energy and its contractors, for a processing fee, from:

109

DOE Challenge Home Case Study, Nexus EnergyHomes, Frederick, MD, Production  

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

Nexus Nexus EnergyHomes Frederick, MD BUILDING TECHNOLOGIES OFFICE DOE Challenge Home builders are in the top 1% of builders in the country meeting the extraordinary levels of excellence and quality specifi ed by the U.S. Department of Energy. Every DOE Challenge Home starts with ENERGY STAR for Homes Version 3 for an energy-effi cient home built on a solid foundation of building science research. Then, even more advanced technologies are designed in for a home that goes above and beyond current code to give you the superior quality construction, HVAC, appliances, indoor air quality, safety, durability, comfort, and solar-ready components along with ultra-low or no utility bills. This provides homeowners with a quality home that will last for generations to come.

110

DEPARTMENT OF HEALTH AN~~.N~dtAN, MD. Y.P.H.  

Office of Legacy Management (LM)

,' ,...- ,' ,...- -., -.- . . we#lnty..: - DEPARTMENT OF HEALTH AN~~.N~dtAN, MD. Y.P.H. April 30, 1979 . _-- _' . U.S.E.P.A. Radiation Branch 26 Federal Plaz;a, Boom 9079 New York, N. Y. 10007 Attention: Miss Feldman:, Gentlemen: In accordance with your request to Calvin E. Weber, P.E., Assistant Commissioner of Health for Environmental Quality, I am forwarding a copy of a report prepared by him concerning a radiation survey conducted in the vicinity of the former Canadian Radium and Uranium Corpora+on plant on Railroad Avenue in the Village of Mount Kisco, Westchester County, New Yor Please transmit any comments you may have regarding this matter directly to Mr. Weber. Very truly Yours, Conmissioner of Health xc:rr cc: Sherwood Davies, P.E. lbm Cashman

111

Recipient: County of Howard, MD ENERGY EFFICIENCY AND CONSERVATION BLOCK GRANTS NEPA COMPLIANCE FORM  

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

2 2 Recipient: County of Howard, MD ENERGY EFFICIENCY AND CONSERVATION BLOCK GRANTS NEPA COMPLIANCE FORM Activities Determination/ Categorical Exclusion Reviewer's Specific Instructions and Rationale (Restrictions and Allowable Activity) Electric Pick-up truck for on- site use at Alpha Ridge Landfill B5.1 None Landfill Forced Draft Heater A9 This CX applies to preliminary engineering and design tasks only. Additional information is required to make a NEPA determination for construction and operation tasks. Diesel Hybrid Truck B5.1 None Home Energy Audits A9 None Park Ballfield Lights Energy Efficiency B5.1 Waste Stream Clause Energy Efficiency Analysis via Monitoring of Sub-Meters Installation B5.1 None Energy Management Consultant A9 None High Efficiency Lighting - Rec & Parks B5.1

112

Recipient. County of Baltimore, MD ENERGY EFFICIENCY AND CONSERVATION BLOCK GRANTS NEPA  

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

0 0 Recipient. County of Baltimore, MD ENERGY EFFICIENCY AND CONSERVATION BLOCK GRANTS NEPA COMPLIANCE FORM Activities Determination/ Categorical Exclusion Reviewer's Specific Instructions and Rationale (Restrictions and Allowable Activity) Renovation for the Green Resource Center B5.1 All administrative activities, audits, outreach, and technical advice should be CX'd. All EE activities are subject to the Waste Stream Clause, Historic Preservation clause, and Engineering clause. Energy Audits for Business & Government Structures A9, All, B5.1 None Revolving Loan Fund A9, All, B5.1 All administrative activities, audits, outreach, and technical advice should be CX'd. All EE activities are subject to the Waste Stream Clause, Historic Preservation clause, and Engineering clause.

113

Oral Histories: Dr. John W. Gofman, M.D., Ph.D.  

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

7 7 HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Dr. John W. Gofman, M.D., Ph.D. Conducted December 20, 1994 United States Department of Energy Office of Human Radiation Experiments June 1995 CONTENTS Foreword Short Biography Oberlin College, Enrollment in Western Reserve Medical School To University of California, Berkeley to Study Physical Chemistry Assisting Seaborg's Research, Discovery of Uranium-233 The Manhattan Project From Research to Laboratory Production of Plutonium Joe Hamilton's Cavalier Approach to Radiation Medical Treatments With Radioactive Phosphorus (32P) Conflict Between University of California San Francisco and Berkeley Reflections on Ernest Lawrence Heart Disease Studies AEC Support for Heart Disease Studies Heparin and Lipoprotein Research With Human Subjects

114

Oral Histories: Oral History of Radiologist Henry I. Kohn, M.D., Ph.D.  

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

1 1 HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Radiologist Henry I. Kohn, M.D., Ph.D. Conducted September 13, 1994 United States Department of Energy Office of Human Radiation Experiments June 1995 CONTENTS Foreword Short Biography Studying the Effects of X Rays on Animal Blood Chemistry at Oak Ridge Work at UCSF's Radiological Laboratory Advantages of Yeast Cells for Studying Radiation Effects Reflections on Bert Low-Beer and Joseph Hamilton Radiation Genetics Experiments on Mice Reflections on Reynold Brown and Henry Kaplan Establishment of Harvard's Joint Center for Radiation Therapy (Mid '60s) Radiological Assessment for the National Academy of Science Survey of Nuclear and Alternative Energy (1975–79) Biologist and Physicist Perspectives on Radiological Effects

115

Felix F? Camacho Governor Michael W. Cruz, M.D. Lieutenant Governor  

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

O. Box 2950 Haghiia, Guam 96932 O. Box 2950 Haghiia, Guam 96932 TEL: (671) 472-8931 FAX: (671) 477-4826 EMAIL: governo@mail.gov.gu Felix F? Camacho Governor Michael W. Cruz, M.D. Lieutenant Governor 0 6 MAW 2009 The Honorable Steven Chu Secretary U.S. Department of Energy 1000 Independence Avenue, S. W. Washington, D.C. 20585 Re: State Energy Program Assurances Dear Secretary Chu: As a condition of receiving Guam's share of the $3.1 billion funding for the State Energy Program (SEP) under the American Recovery and Renewal Act of 2009 (H.R. l)(ARRA), I am providing the following assurances. I have written to the Consolidated Commission on Utilities, Guam's public utility commission, and requested that they consider additional actions to promote energy efficiency, consistent with the Federal

116

Molecular dynamics simulation of UO2 nanocrystals melting  

E-Print Network (OSTI)

In this article we study melting of uranium dioxide (UO2) nanocrystals (NC) isolated in vacuum (i.e. non-periodic boundary conditions) using molecular dynamics (MD) in the approximation of pair potentials and rigid ions. We calculate the size dependence of the temperature and heat of melting, the density jump for crystals of cubic shape and volumes up to 1000 nm^3 (50000 particles). Linear and parabolic extrapolations of these dependences to macroscopic (infinite) size are considered, the parabolic is found to be better suited for the analysis of data on the temperature and the heat of melting. The closest to the modern experimental data estimates of the melting temperature of macrocrystals are obtained using the interaction potentials Goel-08 (2969K), Yakub-09 (3105K) and MOX-07 (3291K). The density jump at melting is well reproduced by Yakub-09 (8.66%) and MOX-07 (7.97%). The heat of fusion for all sets of the potentials considered is found to be underestimated by 50-75%, possibly because of the excluded he...

Boyarchenkov, A S; Nekrasov, K A; Kupryazhkin, A Ya

2011-01-01T23:59:59.000Z

117

California Health eQuality Advisory Committee Kenneth W. Kizer, M.D., M.P.H. -Chair  

E-Print Network (OSTI)

California Health eQuality Advisory Committee Kenneth W. Kizer, M.D., M.P.H. - Chair Distinguished Association (IHA) Ellen Wu, M.P.H. Executive Director California Pan-Ethnic Health Network Pamela L. Lane, M.S., RHIA, CPHIMS, Ex officio Deputy Secretary, HIE California Health & Human Services Agency Linette T

California at Davis, University of

118

Molecular dynamics study of nanoparticle evolution in a background gas under laser ablation conditions  

E-Print Network (OSTI)

Molecular dynamics study of nanoparticle evolution in a background gas under laser ablation,7] are used to explain the evaporation­condensation process. Molecular dynamics (MD) method [4,5,8,9] directly simulates molecular movement and interactions and can be used to investigate the evaporation process

Zhigilei, Leonid V.

119

The implementation of polarizable and flexible models in molecular dynamics simulations  

Science Conference Proceedings (OSTI)

We discuss a new methodology for implementing polarizable and flexible molecular models - the fluctuating charge and intramolecular potential (fCINTRA) method - in Molecular Dynamics (MD) simulations. An example has been provided for ethanol. In these ... Keywords: message passing interface, molecular dynamics simulation, polarizable and flexible model

Shihao Wang; Natalie M. Cann

2009-06-01T23:59:59.000Z

120

Oral Histories: Physician James S. Robertson, M.D., Ph.D.  

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

8 8 HUMAN RADIATION STUDIES: REMEMBERING THE EARLY YEARS Oral History of Physician James S. Robertson, M.D., Ph.D. Conducted January 20, 1995 United States Department of Energy Office of Human Radiation Experiments September 1995 CONTENTS Foreword Short Biography Education Research on Human Subjects at Berkeley Invited to Join the New Lab at Brookhaven (1950) Boron Neutron Capture Therapy Other AEC Biomedical Programs Brookhaven Human Use Committee Castle Bravo Atomic Weapon Test (March 1, 1954) Studies on Marshallese at Brookhaven Modern BNCT Treatment Leaves Brookhaven for the Mayo Clinic (1975) Joins the Department of Energy (1983) Work at the Naval Radiological Defense Laboratory (1953–55) Controversial Treatments and the "Crackpot File" FOREWORD I n December 1993, U.S. Secretary of Energy Hazel R. O'Leary announced her Openness Initiative. As part of this initiative, the Department of Energy undertook an effort to identify and catalog historical documents on radiation experiments that had used human subjects. The Office of Human Radiation Experiments coordinated the Department's search for records about these experiments. An enormous volume of historical records has been located. Many of these records were disorganized; often poorly cataloged, if at all; and scattered across the country in holding areas, archives, and records centers.

Note: This page contains sample records for the topic "dynamics md density" from the National Library of EnergyBeta (NLEBeta).
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121

Effects of confinement on water structure and dynamics and on proton transport: a molecular simulation study  

E-Print Network (OSTI)

Classical molecular dynamics (MD) simulations are performed to study structural and dynamic properties of water confined within graphite surfaces. The surfaces are separated at distances varying between 7 and 14.5 Å and the water density is held constant at 1g/cc. Results at 298 K show the formation of a well-ordered structure constituted by water layers parallel to the graphite surfaces. The water molecules in the layers in contact with the surface have a tendency to orient their dipole parallel to the surface. Such ice-like structures may have different structural and dynamic properties than those of ice. The calculated mean square displacement reveals that the mobilities of the confined water at a separation of 8 Å become similar to that of low-temperature water (213 K) at the same density, although the structures of water are very different. The temperature at which the mobility of water confined at the separation of 7 Å would become similar to that of bulk low-temperature water was found to be 373K. With respect to the dynamics of confined water, a significant blue shift is observed in the intermolecular vibrational modes associated with the O×××O×××O bending and O×××O stretching of molecules linked by hydrogen bonds. The analysis of the geometry of water clusters confined between two graphite surfaces has been performed using ab initio methods. The ab initio calculations yield two preferential orientations of water molecules which are; 1) one O-H bond points to the surface and the other is parallel; 2) both O-H bonds are parallel to the surface. These orientations agree with those found in our MD simulation results. The calculated energy barriers for proton transfer of the confined H3O+-(H2O) complexes between two graphite model surfaces suggest that the confinement enhances the proton transfer at the separation 6-14.5 Å. When the confinement is high, at a separation of 4 Å, the barrier energies are extremely large. The confinement does not enhance proton transfer when the H3O+-(H2O) complexes are located further from the surfaces by more than 8 Å. As a result, the barrier energies start to increase at the separation of 20 Å.

Hirunsit, Pussana

2007-05-01T23:59:59.000Z

122

Kinetic energy deficit in the symmetric fission of /sup 259/Md. [Light particle emission in /sup 256/Fm fission  

Science Conference Proceedings (OSTI)

The fragment energies of about 725 coincidence events have now been observed in the spontaneous fission (SF) decay of 105-min /sup 259/Md since its discovery in 1977. The fission of /sup 259/Md is characterized by a symmetric mass distribution, similar to those of /sup 258/Fm and /sup 259/Fm, but with a broad total kinetic energy (anti TKE) distribution which peaks at about 195 MeV, in contrast to those of /sup 258/Fm and /sup 259/Fm, for which the anti TKE is about 240 MeV. This kinetic energy deficit, approx. 40 MeV, has been postulated to be due to the emission of hydrogen-like particles by /sup 259/Md at the scission point in a large fraction of the fissions, leaving the residual fissioning nucleus with 100 protons. The residual nucleus would then be able to divide into two ultrastable tin-like fission fragments, but with less kinetic energy than that observed in the SF of /sup 258/Fm and /sup 259/Fm, because of binding-energy losses and a reduction in the Coulomb repulsion of the major fragments. To test this hypothesis, counter-telescope experiments aimed at detecting and identifying these light particles were performed. In 439 SF events 3 + 3 protons of the appropriate energy were observed, too few to account for the kinetic energy deficit in the fission of /sup 259/Md. There seems to be no explanation for this problem within the framework of current fission theory. These results are discussed along with preliminary measurements of light-particle emission in the SF of /sup 256/Fm. 5 figures.

Hulet, E.K.; Wild, J.F.; Lougheed, R.W.; Baisden, P.A.; Dougan, R.J.; Mustafa, M.G.

1980-10-01T23:59:59.000Z

123

Scattering Length Density Calculator  

Science Conference Proceedings (OSTI)

... For energy dependent cross sections please go to ... The neutron scattering length density is defined ... To calculate scattering length densities enter a ...

124

Hydrogenation and surface density changes in hydrocarbon films during erosion using Ar/H{sub 2} plasmas  

SciTech Connect

We report interactions of low pressure Ar, H{sub 2}, and Ar/H{sub 2} mixture plasmas with a-C:H films. Surface evolution and erosion of a-C:H films were examined for ion energies up to 200 eV by rf biasing the substrates. Film surfaces were characterized using in situ ellipsometry, x-ray photoelectron spectroscopy, and atomic force microscopy. Multilayer models for steady-state modified surface layers are constructed using ellipsometric data and compared with results of molecular dynamics (MD) simulations and transport of ions in matter (TRIM) calculations. We find that Ar plasma causes a modified layer at the surface that is depleted of H atoms. The depth and degree of this modification is strongly depending on Ar ion energies. This depletion saturates quickly during plasma exposure (<1 s) and persists during steady-state erosion. We find that the thickness and density of the H-depleted layer are in good agreement with MD and TRIM simulations. The degree of surface densification decreases when small amounts of H{sub 2} are added to Ar plasmas. When more than 5% H{sub 2} is added to the plasma, long term loss in surface density is observed, indicating rehydrogenation and saturation of H in the film. As the H{sub 2} fraction increases, the near-surface atomic H increases and the ion composition bombarding the surface changes. This causes incorporation of H deeper into the a-C:H film. For a-C:H films exposed to pure H{sub 2} plasmas, H is introduced into the near-surface region to a depth of up to {approx}8 nm from the surface. As the rf bias is increased the ion energy transitions from solely chemical sputtering to one involving physical sputtering, causing the yield of C atoms from the surface to greatly increase. The increasing yield suppresses H incorporation/saturation and decreases the magnitude of the modified surface layer.

Fox-Lyon, N.; Oehrlein, G. S. [Department of Materials Science and Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States); Ning, N.; Graves, D. B. [Department of Chemical Engineering, University of California, Berkeley, California 94720 (United States)

2011-11-15T23:59:59.000Z

125

Molecular Dynamics Simulation of Tri-n-Butyl-Phophate Liquid: A Force Field Comparative Study  

SciTech Connect

Molecular dynamics (MD) simulations were conducted to compare the performance of four force fields in predicting thermophysical properties of tri-n-butyl-phosphate (TBP) in the liquid phase. The intramolecular force parameters used were from the Assisted Model Building with Energy Refinement (AMBER) force field model. The van der Waals parameters were based on either the AMBER or the Optimized Potential for Liquid Simulation (OPLS) force fields. The atomic partial charges were either assigned by performing quantum chemistry calculations or utilized previously published data, and were scaled to approximate the average experimental value of the electric dipole moment. Canonical ensemble computations based on the aforementioned parameters were performed near the atmospheric pressure and temperature to obtain the electric dipole moment, mass density, and self-diffusion coefficient. In addition, the microscopic structure of the liquid was characterized via pair correlation functions between selected atoms. It has been demonstrated that the electric dipole moment can be approximated within 1% of the average experimental value by virtue of scaled atomic partial charges. The liquid mass density can be predicted within 0.5-1% of its experimentally determined value when using the corresponding charge scaling. However, in all cases the predicted self- diffusion coefficient is significantly smaller than a commonly quoted experimental measurement; this result is qualified by the fact that the uncertainty of the experimental value was not available.

Cui, Shengting [ORNL; de Almeida, Valmor F [ORNL; Hay, Benjamin [ORNL; Ye, Xianggui [ORNL; Khomami, Bamin [ORNL

2012-01-01T23:59:59.000Z

126

Modeling ramp compression experiments using large-scale molecular dynamics simulation.  

Science Conference Proceedings (OSTI)

Molecular dynamics simulation (MD) is an invaluable tool for studying problems sensitive to atomscale physics such as structural transitions, discontinuous interfaces, non-equilibrium dynamics, and elastic-plastic deformation. In order to apply this method to modeling of ramp-compression experiments, several challenges must be overcome: accuracy of interatomic potentials, length- and time-scales, and extraction of continuum quantities. We have completed a 3 year LDRD project with the goal of developing molecular dynamics simulation capabilities for modeling the response of materials to ramp compression. The techniques we have developed fall in to three categories (i) molecular dynamics methods (ii) interatomic potentials (iii) calculation of continuum variables. Highlights include the development of an accurate interatomic potential describing shock-melting of Beryllium, a scaling technique for modeling slow ramp compression experiments using fast ramp MD simulations, and a technique for extracting plastic strain from MD simulations. All of these methods have been implemented in Sandia's LAMMPS MD code, ensuring their widespread availability to dynamic materials research at Sandia and elsewhere.

Mattsson, Thomas Kjell Rene; Desjarlais, Michael Paul; Grest, Gary Stephen; Templeton, Jeremy Alan; Thompson, Aidan Patrick; Jones, Reese E.; Zimmerman, Jonathan A.; Baskes, Michael I. (University of California, San Diego); Winey, J. Michael (Washington State University); Gupta, Yogendra Mohan (Washington State University); Lane, J. Matthew D.; Ditmire, Todd (University of Texas at Austin); Quevedo, Hernan J. (University of Texas at Austin)

2011-10-01T23:59:59.000Z

127

Mapping densities in a noisy state space  

E-Print Network (OSTI)

Weak noise smooths out fractals in a chaotic state space and introduces a maximum attainable resolution to its structure. The balance of noise and deterministic stretching/contraction in each neighborhood introduces local invariants of the dynamics that can be used to partition the state space. We study the local discrete-time evolution of a density in a two-dimensional hyperbolic state space, and use the asymptotic eigenfunctions for the noisy dynamics to formulate a new state space partition algorithm.

Domenico Lippolis

2013-03-05T23:59:59.000Z

128

Instabilities in the Nuclear Energy Density Functional  

E-Print Network (OSTI)

In the field of Energy Density Functionals (EDF) used in nuclear structure and dynamics, one of the unsolved issues is the stability of the functional. Numerical issues aside, some EDFs are unstable with respect to particular perturbations of the nuclear ground-state density. The aim of this contribution is to raise questions about the origin and nature of these instabilities, the techniques used to diagnose and prevent them, and the domain of density functions in which one should expect a nuclear EDF to be stable.

M. Kortelainen; T. Lesinski

2010-02-05T23:59:59.000Z

129

Computing 1-D atomic densities in macromolecular simulations: the Density Profile Tool for VMD  

E-Print Network (OSTI)

Molecular dynamics simulations have a prominent role in biophysics and drug discovery due to the atomistic information they provide on the structure, energetics and dynamics of biomolecules. Specialized software packages are required to analyze simulated trajectories, either interactively or via scripts, to derive quantities of interest and provide insight for further experiments. This paper presents the Density Profile Tool, a package that enhances the Visual Molecular Dynamics environment with the ability to interactively compute and visualize 1-D projections of various density functions of molecular models. We describe how the plugin is used to perform computations both via a graphical interface and programmatically. Results are presented for realistic examples, all-atom bilayer models, showing how mass and electron densities readily provide measurements such as membrane thickness, location of structural elements, and how they compare to X-ray diffraction experiments.

Giorgino, Toni

2013-01-01T23:59:59.000Z

130

Probability Densities in Strong Turbulence  

E-Print Network (OSTI)

According to modern developments in turbulence theory, the "dissipation" scales (u.v. cut-offs) $\\eta$ form a random field related to velocity increments $\\delta_{\\eta}u$. In this work we, using Mellin's transform combined with the Gaussain large -scale boundary condition, calculate probability densities (PDFs) of velocity increments $P(\\delta_{r}u,r)$ and the PDF of the dissipation scales $Q(\\eta, Re)$, where $Re$ is the large-scale Reynolds number. The resulting expressions strongly deviate from the Log-normal PDF $P_{L}(\\delta_{r}u,r)$ often quoted in the literature. It is shown that the probability density of the small-scale velocity fluctuations includes information about the large (integral) scale dynamics which is responsible for deviation of $P(\\delta_{r}u,r)$ from $P_{L}(\\delta_{r}u,r)$. A framework for evaluation of the PDFs of various turbulence characteristics involving spatial derivatives is developed. The exact relation, free of spurious Logarithms recently discussed in Frisch et al (J. Fluid Mech. {\\bf 542}, 97 (2005)), for the multifractal probability density of velocity increments, not based on the steepest descent evaluation of the integrals is obtained and the calculated function $D(h)$ is close to experimental data. A novel derivation (Polyakov, 2005), of a well-known result of the multi-fractal theory [Frisch, "Turbulence. {\\it Legacy of A.N.Kolmogorov}", Cambridge University Press, 1995)), based on the concepts described in this paper, is also presented.

Victor Yakhot

2005-12-12T23:59:59.000Z

131

Quantum relaxation dynamics using Bohmian trajectories  

Science Conference Proceedings (OSTI)

We present a new Bohmian trajectory based treatment of quantum dynamics suitable for dissipative systems. Writing the density matrix in complex-polar form

Jeremy B. Maddox; Eric R. Bittner

2001-01-01T23:59:59.000Z

132

Structure and Dynamics of Forsterite-scCO2/H2O Interfaces as a Function of Water Content  

Science Conference Proceedings (OSTI)

Molecular dynamics (MD) simulations of forsterite surfaces in contact with supercritical carbon dioxide (scCO2) fluids of varying water content were performed to determine the partition of water between the scCO2 fluid and the mineral surface, the nature of CO2 and H2O bonding at the interface, and the regions of the interface that may be conducive to HxCO3(2-x)- formation. Calculations of the free energy of the associative adsorption of water onto the (010) forsterite surface from the scCO2 phase indicated that the formation of a water film up to three-monolayer thick can be exothermic even for water contents below the water saturation concentration of the scCO2 fluid. In MD simulations of scCO2/H2O mixtures in contact with the (010) forsterite surface, H2O was found to readily displace CO2 at the surface and, therefore, CO2 directly contacted the surface only for water coverages below two monolayers. For thicker water films, a two-monolayer hydration layer formed that CO2 could not penetrate. Simulations of the hydroxylated (010) surface and of the (011) surface suggested that this conclusion can be extended to forsterite surfaces with different surface structures and/or compositions. The density, diffusion, and degree of hydration of CO2 as well as the extent of CO2/H2O mixing at the interface were all predicted to depend strongly on the thickness of the water-rich film, i.e., on the water content of the scCO2 fluid.

Kerisit, Sebastien N.; Weare, John H.; Felmy, Andrew R.

2012-05-01T23:59:59.000Z

133

Density-dependent covariant energy density functionals  

Science Conference Proceedings (OSTI)

Relativistic nuclear energy density functionals are applied to the description of a variety of nuclear structure phenomena at and away fromstability line. Isoscalar monopole, isovector dipole and isoscalar quadrupole giant resonances are calculated using fully self-consistent relativistic quasiparticle randomphase approximation, based on the relativistic Hartree-Bogoliubovmodel. The impact of pairing correlations on the fission barriers in heavy and superheavy nuclei is examined. The role of pion in constructing desnity functionals is also investigated.

Lalazissis, G. A. [Physics Department, Aristotle University of Thessaloniki, GR-54124 (Greece)

2012-10-20T23:59:59.000Z

134

MD-Predicted Phase diagrams for Pattern Formation due to Ion Irradiation  

E-Print Network (OSTI)

Energetic particle irradiation of solids can cause surface ultra-smoothening, self-organized nanoscale pattern formation, or degradation of the structural integrity of nuclear reactor components. Periodic patterns including high-aspect ratio quantum dots, with occasional long-range order and characteristic spacing as small as 7 nm, have stimulated interest in this method as a means of sub-lithographic nanofabrication. Despite intensive research there is little fundamental understanding of the mechanisms governing the selection of smooth or patterned surfaces, and precisely which physical effects cause observed transitions between different regimes has remained a matter of speculation. Here we report the first prediction of the mechanism governing the transition from corrugated surfaces to flatness, using only parameter-free molecular dynamics simulations of single-ion impact induced crater formation as input into a multi-scale analysis, and showing good agreement with experiment. Our results overturn the paradigm attributing these phenomena to the removal of target atoms via sputter erosion. Instead, the mechanism dominating both stability and instability is shown to be the impact-induced redistribution of target atoms that are not sputtered away, with erosive effects being essentially irrelevant. The predictions are relevant in the context of tungsten plasma-facing fusion reactor walls which, despite a sputter erosion rate that is essentially zero, develop, under some conditions, a mysterious nanoscale topography leading to surface degradation. Our results suggest that degradation processes originating in impact-induced target atom redistribution effects may be important, and hence that an extremely low sputter erosion rate is an insufficient design criterion for morphologically stable solid surfaces under energetic particle irradiation.

Scott A. Norris; Juha Samela; Laura Bukonte; Marie Backman; Djurabekova Flyura; Kai Nordlund; Charbel S. Madi; Michael P. Brenner; Michael J. Aziz

2010-12-23T23:59:59.000Z

135

I The sat (Sl md.re#t IR) inpuFs OyaCIjdo  

E-Print Network (OSTI)

aH a * input cQhrd8&mr: bc;ch ktpm tyva the paeMitv in&rtor to vvhen"b ' is low, the activehDgh outpu? is forced high; when "R " is low, the active-high output is forced low. Although normally the aotive-low output is drs complement of DUAL DTYPE RIP-FLOP e J-K master/slave The duat D-type flip-flop shown in Figura I of two imht D-tr.pe flip-flops with inputs on the left and flipflops: W mn&h w?U sxta mfy for as long as both "8 ' and "R " wo brcl low. The flip-flop will return to some indeterminate state when both " S and "R " go high. FIGURE 2. Four-Bit Bistable Latch input. tion is derived as follows:- The "DC " input has an AND relationship with the "C " input w shown by the subswipted "C". Therefore, Data passas through "Dc" only when "6 ' is active trua- Input "C " is sensitive to transition, or sensitive as shown by:he ed % (dynamic indicator) symbol.- Absence of the polarity indicator on input "C " means that the MORE E level is true. Therefore, ive true on a low-to-hi& tramis# * and when "C " is active true as stated &over data is passed through and active low outputs are by the abseme/presence of tarritvindicator {-P 1. FOUR-BIT BISTABLE LATCH The fourbit bistable latch shown in Figure 2 consists of four independent D-type flip-flops. FFI and FF2 are controlled by the 61 dock input, and FF3 and FF4 are controlled by the C2 clock input. This is evident by the subscripted C1 and C2 on the input data lines. Information present at a data (Dc) input is transferred to the active-high and active-low outputs when the associated clock input is high: the outputs will follow the data as long as the clock remains high. When the clock goes low, the information that was present at the data input when t4e transition occurred is retained at the outputs until the dock returns high. WWW.HPARCHIVE.COM-flops. Inputs to the master section on the left side are controlled by the gate (G) pulse. The gate pulse also controls the state of the coupling transistors (not shown) wh connect the mmw aprd dm

unknown authors

1976-01-01T23:59:59.000Z

136

Mass Transport Properties of LiD-U Mixtures from Orbital Free Molecular Dynamics Simulations and a Pressure-Matching Mixing Rule  

SciTech Connect

Mass transport properties for LiD-U mixtures were calculated using a pressure matching mixture rule for the mixing of LiD and of U properties simulated with Orbital Free Molecular Dynamics (OFMD). The mixing rule was checked against benchmark OFMD simulations for the fully interacting three-component (Li, D, U) system. To obtain transport coefficients for LiD-U mixtures of different (LiD){sub x}U{sub (1-x)} compositions as functions of temperature and mixture density is a tedious task. Quantum molecular dynamics (MD) simulations can be employed, as in the case LiD or U. However, due to the presence of the heavy constituent U, such simulations proceed so slowly that only a limited number of numerical data points in the (x, {rho}, T) phase space can be obtained. To finesse this difficulty, transport coefficients for a mixture can be obtained using a pressure-matching mixing rule discussed. For both LiD and U, the corresponding transport coefficients were obtained earlier from quantum molecular dynamics simulations. In these simulations, the quantum behavior of the electrons was represented using an orbital free (OF) version of density functional theory, and ions were advanced in time using classical molecular dynamics. The total pressure of the system, P = nk{sub B}T/V + P{sub e}, is the sum of the ideal gas pressure of the ions plus the electron pressure. The mass self-diffusion coefficient for species {alpha}, D{sub {alpha}}, the mutual diffusion coefficient for species {alpha} and {beta}, D{alpha}{beta}, and the shear viscosity, {eta}, are computed from the appropriate autocorrelation function. The details of similar QMD calculations on LiH are described in Ref. [1] for 0.5 eV < T < 3 eV, and in Ref. [2] for 2 eV < T < 6 eV.

Burakovsky, Leonid [Los Alamos National Laboratory; Kress, Joel D. [Los Alamos National Laboratory; Collins, Lee A. [Los Alamos National Laboratory

2012-05-31T23:59:59.000Z

137

Phase Diagram of Amorphous Solid Water: Low-Density, High-Density, and Very-High-Density Amorphous Ices  

E-Print Network (OSTI)

We describe the phase diagram of amorphous solid water by performing molecular dynamics simulations. Our simulations follow different paths in the phase diagram: isothermal compression/decompression, isochoric cooling/heating and isobaric cooling/heating. We are able to identify low-density amorphous (LDA), high-density amorphous (HDA), and very-high density amorphous (VHDA) ices. The density $\\rho$ of these glasses at different pressure $P$ and temperature $T$ agree well with experimental values. We also study the radial distribution functions of glassy water. We obtain VHDA by isobaric heating of HDA, as in experiment. We also find that ``other forms'' of glassy water can be obtained upon isobaric heating of LDA, as well as amorphous ices formed during the transformation of LDA to HDA. We argue that these other forms of amorphous ices, as well as VHDA, are not altogether new glasses but rather are the result of aging induced by heating. Samples of HDA and VHDA with different densities are recovered at normal $P$, showing that there is a continuum of glasses. Furthermore, the two ranges of densities of recovered HDA and recovered VHDA overlap at ambient $P$. Our simulations are consistent with the possibility of HDA$\\to$LDA and VHDA$\\to$LDA transformations, reproducing the experimental findings. We do not observe a VHDA$\\to$HDA transformation.

Nicolas Giovambattista; H. Eugene Stanley; Francesco Sciortino

2005-02-22T23:59:59.000Z

138

Density | OpenEI  

Open Energy Info (EERE)

Density Density Dataset Summary Description This dataset is part of a larger internal dataset at the National Renewable Energy Laboratory (NREL) that explores various characteristics of large solar electric (both PV and CSP) facilities around the United States. This dataset focuses on the land use characteristics for solar facilities that are either under construction or currently in operation. Source Land-Use Requirements for Solar Power Plants in the United States Date Released June 25th, 2013 (5 months ago) Date Updated Unknown Keywords acres area average concentrating solar power csp Density electric hectares km2 land land requirements land use land-use mean photovoltaic photovoltaics PV solar statistics Data application/vnd.openxmlformats-officedocument.spreadsheetml.sheet icon Master Solar Land Use Spreadsheet (xlsx, 1.5 MiB)

139

Single-Nucleon Densities  

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

Densities Densities This web page presents single-nucleon densities calculated for a variety of nuclei in the range A=2-10 with some preliminary results for A=11,12. These are from variational Monte Carlo calculations (VMC) using the Argonne v18 two-nucleon and Urbana X three-nucleon potentials (AV18+UX). (Urbana X is intermediate between the Urbana IX and Illinois-7 models; it has the form of UIX supplemented with a two-pion S-wave piece, while the strengths of its terms are taken from the IL7 model. It does NOT have the three-pion-ring term of IL7.) These VMC wave functions are the starting trial functions for a number of recent Green's function Monte Carlo (GFMC) calculations: Brida, et al., Phys. Rev. C 84, 024319 (2011); McCutchan, et al., Phys. Rev. C 86, 024315 (2012);

140

Multiple density layered insulator  

DOE Patents (OSTI)

A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

Alger, T.W.

1994-09-06T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

Multiple density layered insulator  

DOE Patents (OSTI)

A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

Alger, Terry W. (Tracy, CA)

1994-01-01T23:59:59.000Z

142

Near quantitative agreement of model free DFT- MD predictions with XAFS observations of the hydration structure of highly charged transition metal ions  

Science Conference Proceedings (OSTI)

DFT-MD simulations (PBE96 and PBE0) with MD-XAFS scattering calculations (FEFF9) show near quantitative agreement with new and existing XAFS measurements for a comprehensive series of transition metal ions which interact with their hydration shells via complex mechanisms (high spin, covalency, charge transfer, etc.). This work was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory (PNNL) is operated for the U.S. DOE by Battelle. A portion of the research was performed using EMSL, a national scientific user facility sponsored by the U.S. DOE's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory.

Fulton, John L.; Bylaska, Eric J.; Bogatko, Stuart A.; Balasubramanian, Mahalingam; Cauet, Emilie L.; Schenter, Gregory K.; Weare, John H.

2012-09-20T23:59:59.000Z

143

Force-field development and molecular dynamics simulations of ferrocene-peptide conjugates as a scaffold for hydrogenase mimics.  

Science Conference Proceedings (OSTI)

The increasing importance of hydrogenase enzymes in the new energy research field has led us to examine the structure and dynamics of potential hydrogenase mimics, based on a ferrocene-peptide scaffold, using molecular dynamics (MD) simulations. To enable this MD study, a molecular mechanics force field for ferrocene-bearing peptides was developed and implemented in the CHARMM simulation package, thus extending the usefulness of the package into peptide-bioorganometallic chemistry. Using the automated frequency-matching method (AFMM), optimized intramolecular force-field parameters were generated through quantum chemical reference normal modes. The partial charges for ferrocene were derived by fitting point charges to quantum-chemically computed electrostatic potentials. The force field was tested against experimental X-ray crystal structures of dipeptide derivatives of ferrocene-1,1{prime}-dicarboxylic acid. The calculations reproduce accurately the molecular geometries, including the characteristic C2-symmetrical intramolecular hydrogen-bonding pattern, that were stable over 0.1{micro}s MD simulations. The crystal packing properties of ferrocene-1-(D)alanine-(D)proline{prime}-1-(D)alanine-(D)proline were also accurately reproduced. The lattice parameters of this crystal were conserved during a 0.1 s MD simulation and match the experimental values almost exactly. Simulations of the peptides in dichloromethane are also in good agreement with experimental NMR and circular dichroism (CD) data in solution. The developed force field was used to perform MD simulations on novel, as yet unsynthesized peptide fragments that surround the active site of [Ni-Fe] hydrogenase. The results of this simulation lead us to propose an improved design for synthetic peptide-based hydrogenase models. The presented MD simulation results of metallocenes thereby provide a convincing validation of our proposal to use ferrocene-peptides as minimal enzyme mimics.

De Hatten, Xavier [University of Bordeaux; Cournia, Zoe [Yale University; Smith, Jeremy C [ORNL; Metzler-Nolte, Nils [University of Bochum, Germany

2007-08-01T23:59:59.000Z

144

Force-field development and molecular dynamics simulations of ferrocene-peptide conjugates as a scaffold for hydrogenase mimics  

Science Conference Proceedings (OSTI)

The increasing importance of hydrogenase enzymes in the new energy research field has led us to examine the structure and dynamics of potential hydrogenase mimics, based on a ferrocene-peptide scaffold, using molecular dynamics (MD) simulations. To enable this MD study, a molecular mechanics force field for ferrocene-bearing peptides was developed and implemented in the CHARMM simulation package, thus extending the usefulness of the package into peptide-bioorganometallic chemistry. Using the automated frequency-matching method (AFMM), optimized intramolecular force-field parameters were generated through quantum chemical reference normal modes. The partial charges for ferrocene were derived by fitting point charges to quantum-chemically computed electrostatic potentials. The force field was tested against experimental X-ray crystal structures of dipeptide derivatives of ferrocene-1,1'-dicarboxylic acid. The calculations reproduce accurately the molecular geometries, including the characteristic C{sub 2}-symmetrical intramolecular hydrogen-bonding pattern, that were stable over 0.1 {micro}s MD simulations. The crystal packing properties of ferrocene-1-(D)alanine-(D)proline-1'-(D)alanine-(D)proline were also accurately reproduced. The lattice parameters of this crystal were conserved during a 0.1 {micro}s MD simulation and match the experimental values almost exactly. Simulations of the peptides in dichloromethane are also in good agreement with experimental NMR and circular dichroism (CD) data in solution. The developed force field was used to perform MD simulations on novel, as yet unsynthesized peptide fragments that surround the active site of [Ni-Fe] hydrogenase. The results of this simulation lead us to propose an improved design for synthetic peptide-based hydrogenase models. The presented MD simulation results of metallocenes thereby provide a convincing validation of our proposal to use ferrocene-peptides as minimal enzyme mimics.

De Hatten, Xavier [University of Bordeaux; Cournia, Zoe [Yale University; Smith, Jeremy C [ORNL; Huc, I [University of Bochum, Germany; Metzler-Nolte, Nils [University of Bochum, Germany

2007-08-01T23:59:59.000Z

145

Early maturation processes in coal. Part 2: Reactive dynamics simulations using the ReaxFF reactive force field on Morwell Brown coal structures  

E-Print Network (OSTI)

Early maturation processes in coal. Part 2: Reactive dynamics simulations using the ReaxFF reactive force field on Morwell Brown coal structures Elodie Salmon a , Adri C.T. van Duin b , François Lorant Brown coal using the ReaxFF reactive force field. We find that these reactive MD simulations

Goddard III, William A.

146

High Energy Density Capacitors  

SciTech Connect

BEEST Project: Recapping is developing a capacitor that could rival the energy storage potential and price of today’s best EV batteries. When power is needed, the capacitor rapidly releases its stored energy, similar to lightning being discharged from a cloud. Capacitors are an ideal substitute for batteries if their energy storage capacity can be improved. Recapping is addressing storage capacity by experimenting with the material that separates the positive and negative electrodes of its capacitors. These separators could significantly improve the energy density of electrochemical devices.

None

2010-07-01T23:59:59.000Z

147

The Subthermocline Lens D1. Part II: Kinematics and Dynamics  

Science Conference Proceedings (OSTI)

The dynamics of a subthermocline lens observed during the POLYMODE Local Dynamics Experiment are examined using density data and measurements of the velocity field obtained by an absolute velocity profiler. It is shown that the momentum balance ...

B. A. Elliott; T. B. Sanford

1986-03-01T23:59:59.000Z

148

Simulations of liquid ribidium expanded to the critical density  

Science Conference Proceedings (OSTI)

Quantum molecular dynamic simulations were used to examine the change in atomic and electronic structure in liquid rubidium along its liquid-vapor coexistence curve. Starting from the liquid at the triple point, with increasing expansion we observe a continuous increase in the electron localization leading to ion clustering near the metal-nonmetal transition at about twice the critical density, in agreement with electrical measurements, and to the presence of dimers near and below the critical density.

Ross, M; Yang, L H; Pilgrim, W

2006-05-16T23:59:59.000Z

149

Stochastic point kinetics equations in nuclear reactor dynamics.  

E-Print Network (OSTI)

??A system of Itô stochastic differential equations is derived that model the dynamics of the neutron density and the delayed neutron precursors in a point… (more)

Hayes, James G.

2005-01-01T23:59:59.000Z

150

Hydrodynamic slip boundary condition at chemically patterned surfaces: A continuum deduction from molecular dynamics  

E-Print Network (OSTI)

We investigate the slip boundary condition for single-phase flow past a chemically patterned surface. Molecular dynamics (MD) simulations show that modulation of fluid-solid interaction along a chemically patterned surface induces a lateral structure in the fluid molecular organization near the surface. Consequently, various forces and stresses in the fluid vary along the patterned surface. Given the presence of these lateral variations, a general scheme is developed to extract hydrodynamic information from MD data. With the help of this scheme, the validity of the Navier slip boundary condition is verified for the chemically patterned surface, where a local slip length can be defined. Based on the MD results, a continuum hydrodynamic model is formulated using the Navier-Stokes equation and the Navier boundary condition, with a slip length varying along the patterned surface. Steady-state velocity fields from continuum calculations are in quantitative agreement with those from MD simulations. It is shown that, when the pattern period is sufficiently small, the solid surface appears to be homogeneous, with an effective slip length that can be controlled by surface patterning. Such a tunable slip length may have important applications in nanofluidics.

Tiezheng Qian; Xiao-Ping Wang; Ping Sheng

2005-02-26T23:59:59.000Z

151

Anomalous evolution of Ar metastable density with electron density in high density Ar discharge  

SciTech Connect

Recently, an anomalous evolution of argon metastable density with plasma discharge power (electron density) was reported [A. M. Daltrini, S. A. Moshkalev, T. J. Morgan, R. B. Piejak, and W. G. Graham, Appl. Phys. Lett. 92, 061504 (2008)]. Although the importance of the metastable atom and its density has been reported in a lot of literature, however, a basic physics behind the anomalous evolution of metastable density has not been clearly understood yet. In this study, we investigated a simple global model to elucidate the underlying physics of the anomalous evolution of argon metastable density with the electron density. On the basis of the proposed simple model, we reproduced the anomalous evolution of the metastable density and disclosed the detailed physics for the anomalous result. Drastic changes of dominant mechanisms for the population and depopulation processes of Ar metastable atoms with electron density, which take place even in relatively low electron density regime, is the clue to understand the result.

Park, Min; Chang, Hong-Young [Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); You, Shin-Jae; Kim, Jung-Hyung [Center for Vacuum Technology, Korea Research Institute of Standards and Science, Daejeon, 305-306 (Korea, Republic of); Shin, Yong-Hyeon

2011-10-15T23:59:59.000Z

152

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 ...

153

Charge Density Wave Compounds  

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

Fisher Research Group Fisher Research Group Layered Chalcogenides 29 February 2008 Controlling the Wave by Brad Plummer, SLAC Communications Stanford University researchers working in part at SSRL have discovered a novel set of properties pertaining to a compound of materials called tritellurides. These compounds, composed of three atoms of tellurium and a single atom of one of the rare earth elements, demonstrate unique electronic properties that can be controlled by altering the temperature of the material. The tritellurides display phenomena known as charge density waves (CDW). In a normal conductive metal, electrons persist in a "sea" wherein they are evenly distributed and equally available, or conductive. A CDW occurs under certain circumstances and causes the electrons to clump together, lowering their availability, and thereby lowering the compound's conductivity. Tellurium, when crystallized into quasi-two-dimensional planes and combined with rare earth elements, produces a material with CDWs that can be manipulated and controlled.

154

Low density microcellular foams  

DOE Patents (OSTI)

Disclosed is a process of producing microcellular from which comprises the steps of: (a) selecting a multifunctional epoxy oligomer resin; (b) mixing said epoxy resin with a non-reactive diluent to form a resin-diluent mixture; (c) forming a diluent containing cross-linked epoxy gel from said resin-diluent mixture; (d) replacing said diluent with a solvent therefore; (e) replacing said solvent with liquid carbon dioxide; and (f) vaporizing off said liquid carbon dioxide under supercritical conditions, whereby a foam having a density in the range of 35-150 mg/cc and cell diameters less than about 1 .mu.m is produced. Also disclosed are the foams produced by the process.

LeMay, James D. (Castro Valley, CA)

1992-01-01T23:59:59.000Z

155

Low density microcellular foams  

DOE Patents (OSTI)

Disclosed is a process of producing microcellular foam which comprises the steps of: (a) selecting a multifunctional epoxy oligomer resin; (b) mixing said epoxy resin with a non-reactive diluent to form a resin-diluent mixture; (c) forming a diluent containing cross-linked epoxy gel from said resin-diluent mixture; (d) replacing said diluent with a solvent therefore; (e) replacing said solvent with liquid carbon dioxide; and (f) vaporizing off said liquid carbon dioxide under supercritical conditions, whereby a foam having a density in the range of 35-150 mg/cc and cell diameters less than about 1 .mu.m is produced. Also disclosed are the foams produced by the process.

LeMay, James D. (Castro Valley, CA)

1991-01-01T23:59:59.000Z

156

Density Coordinate Mixed Layer Models  

Science Conference Proceedings (OSTI)

The development of mixed layer models in so-called density coordinates is discussed. Density coordinates, or isopycnal coordinates as they are sometimes called, are becoming increasingly popular for use in ocean models due to their highly ...

William K. Dewar

2001-02-01T23:59:59.000Z

157

Sensitivity of nuclear stopping towards density dependent symmetry energy  

E-Print Network (OSTI)

The effect of density dependent symmetry energy on nuclear-stopping is studied using isospin-dependent quantum molecular dynamics model(IQMD). We have used the reduced isospin-dependent cross-section with soft(S) equation of state for the systems having different isostopic content, to explore the various aspects of nuclear stopping. The aim is to pin down the nature of the nuclear stopping with density dependent symmetry energy. Nuclear stopping is found to be sensitive towards the various forms of the density dependent symmetry energy. The nuclear stopping tends to decrease for the stiffer equation of state (EOS), i.e. larger values of gamma.

Karan Singh Vinayak; Suneel Kumar

2011-10-11T23:59:59.000Z

158

Sensitivity of nuclear stopping towards density dependent symmetry energy  

E-Print Network (OSTI)

The effect of density dependent symmetry energy on nuclear-stopping is studied using isospin-dependent quantum molecular dynamics model(IQMD). We have used the reduced isospin-dependent cross-section with soft(S) equation of state for the systems having different isostopic content, to explore the various aspects of nuclear stopping. The aim is to pin down the nature of the nuclear stopping with density dependent symmetry energy. Nuclear stopping is found to be sensitive towards the various forms of the density dependent symmetry energy. The nuclear stopping tends to decrease for the stiffer equation of state (EOS), i.e. larger values of gamma.

Vinayak, Karan Singh

2011-01-01T23:59:59.000Z

159

Large Scale Computing Requirements for Basic Energy Sciences (An BES / ASCR / NERSC Workshop) Hilton Washington DC/Rockville Meeting Center, Rockville MD 3D Geophysical Imaging  

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

Requirements Requirements for Basic Energy Sciences (An BES / ASCR / NERSC Workshop) Hilton Washington DC/Rockville Meeting Center, Rockville MD 3D Geophysical Modeling and Imaging G. A. Newman Lawrence Berkeley National Laboratory February 9 - 10 , 2010 Talk Outline * SEAM Geophysical Modeling Project - Its Really Big! * Geophysical Imaging (Seismic & EM) - Its 10 to 100x Bigger! - Reverse Time Migration - Full Waveform Inversion - 3D Imaging & Large Scale Considerations - Offshore Brazil Imaging Example (EM Data Set) * Computational Bottlenecks * Computing Alternatives - GPU's & FPGA's - Issues Why ? So that the resource industry can tackle grand geophysical challenges (Subsalt imaging, land acquisition, 4-D, CO2, carbonates ......) SEAM Mission Advance the science and technology of applied

160

Dynamics of a Submesoscale Surface Ocean Density Front  

E-Print Network (OSTI)

609-625. Thomas, L.N. , Tandon, A. , and Mahadevan, A. 2007.C1): Mahadevan, A. , and Tandon, A. 2006. An analysis ofpp. 397–405. Nagai, T. , Tandon, A. , and Rudnick, D.L.

Abramczyk, Marshall

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

Function and dynamics of aptamers: A case study on the malachite green aptamer  

Science Conference Proceedings (OSTI)

Aptamers are short single-stranded nucleic acids that can bind to their targets with high specificity and high affinity. To study aptamer function and dynamics, the malachite green aptamer was chosen as a model. Malachite green (MG) bleaching, in which an OH- attacks the central carbon (C1) of MG, was inhibited in the presence of the malachite green aptamer (MGA). The inhibition of MG bleaching by MGA could be reversed by an antisense oligonucleotide (AS) complementary to the MGA binding pocket. Computational cavity analysis of the NMR structure of the MGA-MG complex predicted that the OH{sup -} is sterically excluded from the C1 of MG. The prediction was confirmed experimentally using variants of the MGA with changes in the MG binding pocket. This work shows that molecular reactivity can be reversibly regulated by an aptamer-AS pair based on steric hindrance. In addition to demonstrate that aptamers could control molecular reactivity, aptamer dynamics was studied with a strategy combining molecular dynamics (MD) simulation and experimental verification. MD simulation predicted that the MG binding pocket of the MGA is largely pre-organized and that binding of MG involves reorganization of the pocket and a simultaneous twisting of the MGA terminal stems around the pocket. MD simulation also provided a 3D-structure model of unoccupied MGA that has not yet been obtained by biophysical measurements. These predictions were consistent with biochemical and biophysical measurements of the MGA-MG interaction including RNase I footprinting, melting curves, thermodynamic and kinetic constants measurement. This work shows that MD simulation can be used to extend our understanding of the dynamics of aptamer-target interaction which is not evident from static 3D-structures. To conclude, I have developed a novel concept to control molecular reactivity by an aptamer based on steric protection and a strategy to study the dynamics of aptamer-target interaction by combining MD simulation and experimental verification. The former has potential application in controlling metabolic reactions and protein modifications by small reactants and the latter may serve as a general approach to study the dynamics of aptamer-target interaction for new insights into mechanisms of aptamer-target recognition.

Wang, Tianjiao

2008-12-01T23:59:59.000Z

162

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

163

Investigation of asymmetric plasma blob dynamics  

E-Print Network (OSTI)

The dynamics of asymmetric blobs is investigated in the Versatile Toroidal Facility (VTF) at MIT. Blobs are local regions of enhanced plasma density. Blobs are relevant to several areas of physics research, including fusion ...

Soane, Alexander (Alexander Visotsky)

2009-01-01T23:59:59.000Z

164

Energy trapping from Hagedorn densities of states  

E-Print Network (OSTI)

In this note, we construct simple stochastic toy models for holographic gauge theories in which distributions of energy on a collection of sites evolve by a master equation with some specified transition rates. We build in only energy conservation, locality, and the standard thermodynamic requirement that all states with a given energy are equally likely in equilibrium. In these models, we investigate the qualitative behavior of the dynamics of the energy distributions for different choices of the density of states for the individual sites. For typical field theory densities of states (\\log(\\rho(E)) ~ E^{\\alphaenergy spread out relatively quickly. For large N gauge theories with gravitational duals, the density of states for a finite volume of field theory degrees of freedom typically includes a Hagedorn regime (\\log(\\rho(E)) ~ E). We find that this gives rise to a trapping of energy in subsets of degrees of freedom for parametrically long time scales before the energy leaks away. We speculate that this Hagedorn trapping may be part of a holographic explanation for long-lived gravitational bound states (black holes) in gravitational theories.

Connor Behan; Klaus Larjo; Nima Lashkari; Brian Swingle; Mark Van Raamsdonk

2013-04-26T23:59:59.000Z

165

Density rise experiment on PLT  

SciTech Connect

The evolution of the density profile in PLT during intense gas puffing is documented and analyzed. Measurements of the spectrum of low energy edge neutrals and of the change in central neutral density indicate that charge-exchange processes alone cannot account for the central density rise. The transient density profile changes can be reproduced numerically by a diffusivity of approx. 10/sup 4/ cm/sup 2//s, and a spatially averaged inward flow of 10/sup 3/ cm/s. These transport coefficients are 10 ..-->.. 10/sup 2/ times larger than neoclassical. The ion energy confinement is reduced, the small scale density fluctuations are increased, and runaway electrons losses are increased during the density rise.

Strachan, J.D.; Bretz, N.; Mazzucato, E.

1982-05-01T23:59:59.000Z

166

Dynamic Protonation Equilibrium of Solvated Acetic Acid  

Science Conference Proceedings (OSTI)

For the first time, the dynamic protonation equilibrium between an amino acid side chain analogue and bulk water as well as the diffusion properties of the excess proton were successfully reproduced through unbiased computer simulations. During a 50 ns Q-HOP MD simulation, two different regimes of proton transfer were observed. Extended phases of frequent proton swapping between acetic acid and nearby water were separated by phases where the proton freely diffuses in the simulation box until it is captured again by acetic acid. The pKa of acetic acid was calculated around 3.0 based on the relative population of protonated and deprotonated states and the diffusion coefficient of excess proton was computed from the average mean squared displacement in the simulation. Both calculated values agree well with the experimental measurements.

Gu, Wei; Frigato, Tomaso; Straatsma, TP; Helms, Volkhard H.

2007-04-13T23:59:59.000Z

167

Energy Densities for LLNL EMB  

Summary of Projected Power and Energy Density Parameters for the “New Generation” LLNL Electromechanical Batteries R.F. Post June 24, 2013

168

Idealized Numerical Simulations of the Interactions between Buoyant Plumes and Density Currents  

Science Conference Proceedings (OSTI)

Idealized numerical experiments using a large-eddy simulation (LES) model are performed to examine the fundamental dynamical processes associated with the interactions between buoyant plumes and density currents. The aim of these simulations is ...

Philip Cunningham

2007-06-01T23:59:59.000Z

169

Charge transport, configuration interaction and Rydberg states under density functional theory  

E-Print Network (OSTI)

Density functional theory (DFT) is a computationally efficient formalism for studying electronic structure and dynamics. In this work, we develop DFT-based excited-state methods to study electron transport, Rydberg excited ...

Cheng, Chiao-Lun

2008-01-01T23:59:59.000Z

170

Shape control of conditional output probability density functions for linear stochastic systems with random parameters  

Science Conference Proceedings (OSTI)

This paper presents a controller design for shaping conditional output probability density functions (pdf) for non-Gaussian dynamic stochastic systems whose coefficients are random and represented by their known pdfs. The moment-generating ...

Aiping Wang; Yongji Wang; Hong Wang

2011-03-01T23:59:59.000Z

171

An Event-Driven Hybrid Molecular Dynamics and Direct Simulation Monte Carlo Algorithm  

Science Conference Proceedings (OSTI)

A novel algorithm is developed for the simulation of polymer chains suspended in a solvent. The polymers are represented as chains of hard spheres tethered by square wells and interact with the solvent particles with hard core potentials. The algorithm uses event-driven molecular dynamics (MD) for the simulation of the polymer chain and the interactions between the chain beads and the surrounding solvent particles. The interactions between the solvent particles themselves are not treated deterministically as in event-driven algorithms, rather, the momentum and energy exchange in the solvent is determined stochastically using the Direct Simulation Monte Carlo (DSMC) method. The coupling between the solvent and the solute is consistently represented at the particle level, however, unlike full MD simulations of both the solvent and the solute, the spatial structure of the solvent is ignored. The algorithm is described in detail and applied to the study of the dynamics of a polymer chain tethered to a hard wall subjected to uniform shear. The algorithm closely reproduces full MD simulations with two orders of magnitude greater efficiency. Results do not confirm the existence of periodic (cycling) motion of the polymer chain.

Donev, A; Garcia, A L; Alder, B J

2007-07-30T23:59:59.000Z

172

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; ...

173

Density-based logistic regression  

Science Conference Proceedings (OSTI)

This paper introduces a nonlinear logistic regression model for classification. The main idea is to map the data to a feature space based on kernel density estimation. A discriminative model is then learned to optimize the feature weights as well as ... Keywords: density estimation, logistic regression, medical prediction, nonlinear classification

Wenlin Chen, Yixin Chen, Yi Mao, Baolong Guo

2013-08-01T23:59:59.000Z

174

Dynamics of capillary condensation in aerogels  

Science Conference Proceedings (OSTI)

Dynamics of capillary condensation of liquid {sup 4}He in various density silica aerogels was investigated systematically. Interfaces were clearly visible when bulk liquid was rapidly sucked into the aerogel. Time evolution of the interface positions was consistent with the Washburn model and their effective pore radii were obtained. Condensation was a single step in a dense aerogel and two steps in a low density aerogel. Crossover between the two types of condensation was observed in an intermediate density aerogel. Variety of the dynamics may be the manifestation of the fractal nature of aerogels which had a wide range of distribution of pore radii.

Nomura, R.; Miyashita, W.; Yoneyama, K.; Okuda, Y. [Department of Condensed Matter Physics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro, Tokyo 152-8551 (Japan)

2006-03-15T23:59:59.000Z

175

Density Log | Open Energy Information  

Open Energy Info (EERE)

Density Log Density Log Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Density Log Details Activities (6) Areas (6) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Downhole Techniques Exploration Sub Group: Well Log Techniques Parent Exploration Technique: Well Log Techniques Information Provided by Technique Lithology: provides data on the bulk density of the rock surrounding the well Stratigraphic/Structural: Stratigraphic correlation between well bores. Hydrological: Porosity of the formations loggesd can be calculated for the Density log andprovide an indication potential aquifers. Thermal: Cost Information Low-End Estimate (USD): 0.4040 centUSD 4.0e-4 kUSD 4.0e-7 MUSD 4.0e-10 TUSD / foot Median Estimate (USD): 0.6868 centUSD

176

Force spectroscopy of polymer desorption: Theory and Molecular Dynamics simulation  

E-Print Network (OSTI)

Forced detachment of a single polymer chain, strongly-adsorbed on a solid substrate, is investigated by two complementary methods: a coarse-grained analytical dynamical model, based on the Onsager stochastic equation, and Molecular Dynamics (MD) simulations with Langevin thermostat. The suggested approach makes it possible to go beyond the limitations of the conventional Bell-Evans model. We observe a series of characteristic force spikes when the pulling force is measured against the cantilever displacement during detachment at constant velocity $v_c$ (displacement control mode) and find that the average magnitude of this force increases as $v_c$ grows. The probability distributions of the pulling force and the end-monomer distance from the surface at the moment of final detachment are investigated for different adsorption energy $\\epsilon$ and pulling velocity $v_c$. Our extensive MD-simulations validate and support the main theoretical findings. Moreover, the simulation reveals a novel behavior: for a strong-friction and massive cantilever the force spikes pattern is smeared out at large $v_c$. As a challenging task for experimental bio-polymers sequencing in future we suggest the fabrication of stiff, super-light, nanometer-sized AFM probe.

J. Paturej; J. L. A. Dubbeldam; V. G. Rostiashvili; A. Milchev; T. A. Vilgis

2013-10-14T23:59:59.000Z

177

Impact of a vortex ring on a density interface using a regularized inviscid vortex sheet method  

Science Conference Proceedings (OSTI)

A new, fully three-dimensional, vortex-in-cell method designed to follow the unsteady motion of inviscid vortex sheets with or without small (Boussinesq) density discontinuities is presented. As is common in front-tracking methods, the vortex sheet is ... Keywords: Density discontinuity, Stratified flow, Vortex methods, Vortex sheet dynamics, Vortex-in-cell

Mark J. Stock; Werner J. A. Dahm; Grétar Tryggvason

2008-11-01T23:59:59.000Z

178

Optimized local basis set for Kohn-Sham density functional theory  

Science Conference Proceedings (OSTI)

We develop a technique for generating a set of optimized local basis functions to solve models in the Kohn-Sham density functional theory for both insulating and metallic systems. The optimized local basis functions are obtained by solving a minimization ... Keywords: Discontinuous Galerkin, Electronic structure, GMRES, Kohn-Sham density functional theory, Molecular dynamics, Optimized local basis set, Preconditioning, Pulay force, Trace minimization

Lin Lin; Jianfeng Lu; Lexing Ying; Weinan E

2012-05-01T23:59:59.000Z

179

Trapping of a Coastal Density Front by the Bottom Boundary Layer  

Science Conference Proceedings (OSTI)

The dynamics of a surface-to-bottom density front on a uniformly sloping continental shelf and the role of density advection in the bottom boundary layer are examined using a three-dimensional, primitive equation numerical model. The front is ...

David C. Chapman; Steven J. Lentz

1994-07-01T23:59:59.000Z

180

Density and pair-density scaling for deriving the Euler equation in density-functional and pair-density-functional theory  

Science Conference Proceedings (OSTI)

A link between density and pair density functional theories is presented. Density and pair density scaling are used to derive the Euler equation in both theories. Density scaling provides a constructive way of obtaining approximations for the Pauli potential. The Pauli potential (energy) of the density functional theory is expressed as the difference of the scaled and original exchange-correlation potentials (energies).

Nagy, A. [Department of Theoretical Physics, University of Debrecen, H-4010 Debrecen (Hungary)

2011-09-15T23:59:59.000Z

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181

Stochastic Event-Driven Molecular Dynamics  

Science Conference Proceedings (OSTI)

A novel Stochastic Event-Driven Molecular Dynamics (SEDMD) algorithm is developed for the simulation of polymer chains suspended in a solvent. SEDMD combines event-driven molecular dynamics (EDMD) with the Direct Simulation Monte Carlo (DSMC) method. The polymers are represented as chains of hard-spheres tethered by square wells and interact with the solvent particles with hard-core potentials. The algorithm uses EDMD for the simulation of the polymer chain and the interactions between the chain beads and the surrounding solvent particles. The interactions between the solvent particles themselves are not treated deterministically as in EDMD, rather, the momentum and energy exchange in the solvent is determined stochastically using DSMC. The coupling between the solvent and the solute is consistently represented at the particle level retaining hydrodynamic interactions and thermodynamic fluctuations. However, unlike full MD simulations of both the solvent and the solute, in SEDMD the spatial structure of the solvent is ignored. The SEDMD algorithm is described in detail and applied to the study of the dynamics of a polymer chain tethered to a hard-wall subjected to uniform shear. SEDMD closely reproduces results obtained using traditional EDMD simulations with two orders of magnitude greater efficiency. Results question the existence of periodic (cycling) motion of the polymer chain.

Donev, Aleksandar [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-9900 (United States)], E-mail: aleks.donev@gmail.com; Garcia, Alejandro L. [Department of Physics, San Jose State University, San Jose, CA 95192 (United States); Alder, Berni J. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551-9900 (United States)

2008-02-01T23:59:59.000Z

182

Low density carbonized composite foams  

DOE Patents (OSTI)

A carbonized composite foam having a density less than about 50 mg/cm{sup 3} and individual cell sizes no greater than about 1 {mu}m in diameter is described, and the process of making it. 3 figs.

Kong, Fung-Ming.

1989-12-07T23:59:59.000Z

183

Quarkonium at nonzero isospin density  

E-Print Network (OSTI)

We calculate the energies of quarkonium bound states in the presence of a medium of nonzero isospin density using lattice QCD. The medium, created using a canonical (fixed isospin charge) approach, induces a reduction of ...

Detmold, William

184

Rock Density | Open Energy Information  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » Rock Density Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Rock Density Details Activities (2) Areas (2) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Density of different lithologic units. Stratigraphic/Structural: Hydrological: Thermal: Cost Information Low-End Estimate (USD): 10.001,000 centUSD 0.01 kUSD 1.0e-5 MUSD 1.0e-8 TUSD / sample

185

What causes the density effect in young forest plantations?  

DOE Green Energy (OSTI)

In young forest plantations, trees planted at high densities frequently show more rapid height and diameter growth than those plants at lower densities. This positive growth response to density (the ''density effect'') often manifests long before seedlings are tall enough to shade one another, so it is not a simple response to shade. The mechanism(s) which trigger and sustain this growth enhancement are unknown. Our objectives were to document the temporal dynamics of positive growth response to increasing density in Douglas-fir plantations and to test two hypotheses as potential mechanisms for this response. The hypotheses are (1) a canopy boundary layer effect, and (2) alterations in the quality of light reflected from neighboring trees. The ''boundary layer'' hypotheses proposes that changes in atmospheric mixing occur in high-density plantations, promoting increased concentrations of CO{sub 2} and H{sub 2}O vapor during early morning hours, which in turn would enhance carbon assimilation. The ''light quality'' hypothesis proposes that the presence of neighbors alters the ratio of red to far red light in the canopy environment. Plant sensors detect this change in light quality, and growth and development is altered in response. We found that boundary layer conductance was higher, as we predicted, in low-density Douglas-fir stands than in high-density stands five years after planting. The changes in boundary conductance were accompanied by higher CO{sub 2} and H{sub 2}O vapor during early morning hours. However, we also found that the primary manifestation of the density effect in Douglas-fir occurs two to four years after planting, and we were not able to measure differences in boundary conductance in different densities at that time. Also, we found no difference in carbon isotope composition of wood cellulose formed in high- vs. low-density stands two to three years after planting. We conclude that although stand density may have a significant impact on boundary layer conductance in young stands, it does not account for the ''density effect''. Our tests of the light quality hypothesis were slowed due to poor plantation establishment in the early phase of this study. In a variable density experiment we detected significant changes in R:FR related to density. Also in that study we measured a significant enhancement of tree height at high density. However, after three years of growth, the study trees did not show significant differences in stem diameter related to density. Experimenters at Weyerhaeuser therefore decided not to harvest the trees at the end of the 3rd growth year, as originally planned. In a 1-year study of seedlings planted in raised beds subjected to different light quality treatments using transparent plastic film, we found that tree height but not diameter increased in response to decreased R:FR. At this point, we conclude that R:FR remains a viable hypothesis for the ''density effect'', but evidence is not conclusive. We expect that continued measurements in the variable density test plot at Weyerhaeuser will add more evidence in the future.

Barbara J. Bond; Gary A. Ritchie

2002-07-21T23:59:59.000Z

186

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. ...

187

Plasma digital density determining device  

DOE Patents (OSTI)

The density of a decaying plasma in an electrically conducting enclosure is determined by applying an excitation to the cavity formed by the enclosure and counting digitally the number of resonant frequencies traversed by the combination of the cavity and the decaying plasma.

Sprott, Julien C. (Madison, WI); Lovell, Thomas W. (Madison, WI); Holly, Donald J. (Madison, WI)

1976-01-01T23:59:59.000Z

188

Building a Universal Nuclear Energy Density Functional  

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

Building a Universal Nuclear Energy Density Functional Building a Universal Nuclear Energy Density Functional VaryMatrix.png Collaboration with mathematicians and computational...

189

Surface detection, meshing and analysis during large molecular dynamics simulations  

SciTech Connect

New techniques are presented for the detection and analysis of surfaces and interfaces in atomistic simulations of solids. Atomistic and other particle-based simulations have no inherent notion of a surface, only atomic positions and interactions. The algorithms we introduce here provide an unambiguous means to determine which atoms constitute the surface, and the list of surface atoms and a tessellation (meshing) of the surface are determined simultaneously. The algorithms have been implemented and demonstrated to run automatically (on the fly) in a large-scale parallel molecular dynamics (MD) code on a supercomputer. We demonstrate the validity of the method in three applications in which the surfaces and interfaces evolve: void surfaces in ductile fracture, the surface morphology due to significant plastic deformation of a nanoscale metal plate, and the interfaces (grain boundaries) and void surfaces in a nanoscale polycrystalline system undergoing ductile failure. The technique is found to be quite robust, even when the topology of the surfaces changes as in the case of void coalescence where two surfaces merge into one. It is found to add negligible computational overhead to an MD code, and is much less expensive than other techniques such as the solvent-accessible surface.

Dupuy, L M; Rudd, R E

2005-08-01T23:59:59.000Z

190

Enhanced molecular dynamics for simulating porous interphase layers in batteries.  

DOE Green Energy (OSTI)

Understanding charge transport processes at a molecular level using computational techniques is currently hindered by a lack of appropriate models for incorporating anistropic electric fields in molecular dynamics (MD) simulations. An important technological example is ion transport through solid-electrolyte interphase (SEI) layers that form in many common types of batteries. These layers regulate the rate at which electro-chemical reactions occur, affecting power, safety, and reliability. In this work, we develop a model for incorporating electric fields in MD using an atomistic-to-continuum framework. This framework provides the mathematical and algorithmic infrastructure to couple finite element (FE) representations of continuous data with atomic data. In this application, the electric potential is represented on a FE mesh and is calculated from a Poisson equation with source terms determined by the distribution of the atomic charges. Boundary conditions can be imposed naturally using the FE description of the potential, which then propagates to each atom through modified forces. The method is verified using simulations where analytical or theoretical solutions are known. Calculations of salt water solutions in complex domains are performed to understand how ions are attracted to charged surfaces in the presence of electric fields and interfering media.

Zimmerman, Jonathan A.; Wong, Bryan Matthew; Jones, Reese E.; Templeton, Jeremy Alan; Lee, Jonathan (Rice University, Houston, TX)

2009-10-01T23:59:59.000Z

191

Decoherence rates for Galilean covariant dynamics  

E-Print Network (OSTI)

We introduce a measure of decoherence for a class of density operators. For Gaussian density operators in dimension one it coincides with an index used by Morikawa (1990). Spatial decoherence rates are derived for three large classes of the Galilean covariant quantum semigroups introduced by Holevo. We also characterize the relaxation to a Gaussian state for these dynamics and give a theorem for the convergence of the Wigner function to the probability distribution of the classical analog of the process.

Jeremy Clark

2007-10-08T23:59:59.000Z

192

Definition: Density Log | Open Energy Information  

Open Energy Info (EERE)

Density Log Density Log Jump to: navigation, search Dictionary.png Density Log Density logging is a well logging tool that can provide a continuous record of a formation's bulk density along the length of a borehole. In geology, bulk density is a function of the density of the minerals forming a rock (i.e. matrix) and the fluid enclosed in the pore spaces.[1] View on Wikipedia Wikipedia Definition Density logging is a well logging tool that can provide a continuous record of a formation's bulk density along the length of a borehole. In geology, bulk density is a function of the density of the minerals forming a rock and the fluid enclosed in the pore spaces. This is one of three well logging tools that are commonly used to calculate porosity, the other two being sonic logging and neutron porosity logging

193

Relativistic Nuclear Energy Density Functionals: adjusting parameters to binding energies  

E-Print Network (OSTI)

We study a particular class of relativistic nuclear energy density functionals in which only nucleon degrees of freedom are explicitly used in the construction of effective interaction terms. Short-distance (high-momentum) correlations, as well as intermediate and long-range dynamics, are encoded in the medium (nucleon density) dependence of the strength functionals of an effective interaction Lagrangian. Guided by the density dependence of microscopic nucleon self-energies in nuclear matter, a phenomenological ansatz for the density-dependent coupling functionals is accurately determined in self-consistent mean-field calculations of binding energies of a large set of axially deformed nuclei. The relationship between the nuclear matter volume, surface and symmetry energies, and the corresponding predictions for nuclear masses is analyzed in detail. The resulting best-fit parametrization of the nuclear energy density functional is further tested in calculations of properties of spherical and deformed medium-heavy and heavy nuclei, including binding energies, charge radii, deformation parameters, neutron skin thickness, and excitation energies of giant multipole resonances.

T. Niksic; D. Vretenar; P. Ring

2008-09-08T23:59:59.000Z

194

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

195

Vorticity Dynamics and Zonally Averaged Ocean Circulation Models  

Science Conference Proceedings (OSTI)

Diagnostic equations relating the zonally averaged overturning circulation to north–south density variations are derived and used to determine a new closure scheme for use in zonally averaged ocean models. The presentation clarifies the dynamical ...

Daniel G. Wright; Cornelis B. Vreugdenhil; Tertia M. C. Hughes

1995-09-01T23:59:59.000Z

196

Density estimation for data with rounding errors  

Science Conference Proceedings (OSTI)

Rounding of data is common in practice. The problem of estimating the underlying density function based on data with rounding errors is addressed. A parametric maximum likelihood estimator and a nonparametric bootstrap kernel density estimator are proposed. ... Keywords: Bootstrapping, Deconvolution density estimation, Fast Fourier transformation, Kernel density estimation, Measurement error

B. Wang, W. Wertelecki

2013-09-01T23:59:59.000Z

197

Molecular Dynamics Simulations of Folding and Insertion of the Ebola Virus Fusion Peptide into a  

E-Print Network (OSTI)

of Infectious Diseases, Ft. Detrick, MD, USA 2 Biotechnology High Performance Computing Software Applications

198

TIME-DEPENDENT DENSITY DIAGNOSTICS OF SOLAR FLARE PLASMAS USING SDO/EVE  

SciTech Connect

Temporally resolved electron density measurements of solar flare plasmas are presented using data from the EUV Variability Experiment (EVE) on board the Solar Dynamics Observatory. The EVE spectral range contains emission lines formed between 10{sup 4} and 10{sup 7} K, including transitions from highly ionized iron ({approx}>10 MK). Using three density-sensitive Fe XXI ratios, peak electron densities of 10{sup 11.2}-10{sup 12.1} cm{sup -3} were found during four X-class flares. While previous measurements of densities at such high temperatures were made at only one point during a flaring event, EVE now allows the temporal evolution of these high-temperature densities to be determined at 10 s cadence. A comparison with GOES data revealed that the peak of the density time profiles for each line ratio correlated well with that of the emission measure time profile for each of the events studied.

Milligan, Ryan O.; Kennedy, Michael B.; Mathioudakis, Mihalis; Keenan, Francis P. [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, University Road, Belfast BT7 1NN (United Kingdom)

2012-08-10T23:59:59.000Z

199

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

200

Heart DiseaseHeart Disease--Learn to Love YourLearn to Love Your Michael McKee, M.D.Michael McKee, M.D.  

E-Print Network (OSTI)

Heart DiseaseHeart Disease-- Learn to Love YourLearn to Love Your HeartHeart Michael McKee, M.D.Michael McKee, M.D. March 19, 2010March 19, 2010 #12;GoalsGoals ·· Learn more about heart disease for yourself andLearn more about heart disease for yourself and for your studentsfor your students ·· Learn

Goldman, Steven A.

Note: This page contains sample records for the topic "dynamics md density" 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.


201

DENSITY CONTROL IN A REACTOR  

DOE Patents (OSTI)

A reactor is described in which natural-uranium bodies are located in parallel channels which extend through the graphite mass in a regular lattice. The graphite mass has additional channels that are out of the lattice and contain no uranium. These additional channels decrease in number per unit volume of graphite from the center of the reactor to the exterior and have the effect of reducing the density of the graphite more at the center than at the exterior, thereby spreading neutron activity throughout the reactor. (AEC)

Marshall, J. Jr.

1961-10-24T23:59:59.000Z

202

Density and shape factor of sodium aerosol. Progress report, January 1, 1976--March 31, 1976. [LMFBR type reactors  

SciTech Connect

Several approaches for characterizing the physical and aerodynamic properties of irregularly shaped aerosol particles are reviewed. Measurements of density modification factor, dynamic shape factor, and particle density using an aerosol centrifuge and a scanning electron microscope are described. Calibration procedures for this characterization method are described and preliminary results reported.

Hinds, W.; First, M.W.

1976-05-01T23:59:59.000Z

203

Definition: Power density | Open Energy Information  

Open Energy Info (EERE)

density density Jump to: navigation, search Dictionary.png Power density The rate of energy flow (power) per unit volume, area or mass. Common metrics include: horsepower per cubic inch, watts per square meter and watts per kilogram.[1][2] View on Wikipedia Wikipedia Definition Power density (or volume power density or volume specific power) is the amount of power (time rate of energy transfer) per unit volume. In energy transformers like batteries, fuel cells, motors, etc. but also power supply units or similar, power density refers to a volume. It is then also called volume power density which is expressed as W/m. Volume power density is sometimes an important consideration where space is constrained. In reciprocated internal combustion engines, power density- power per swept

204

Lightweight computational steering of very large scale molecular dynamics simulations  

Science Conference Proceedings (OSTI)

We present a computational steering approach for controlling, analyzing, and visualizing very large scale molecular dynamics simulations involving tens to hundreds of millions of atoms. Our approach relies on extensible scripting languages and an easy to use tool for building extensions and modules. The system is extremely easy to modify, works with existing C code, is memory efficient, and can be used from inexpensive workstations and networks. We demonstrate how we have used this system to manipulate data from production MD simulations involving as many as 104 million atoms running on the CM-5 and Cray T3D. We also show how this approach can be used to build systems that integrate common scripting languages (including Tcl/Tk, Perl, and Python), simulation code, user extensions, and commercial data analysis packages.

Beazley, D.M. [Univ. of Utah, Salt Lake City, UT (United States). Dept. of Computer Science; Lomdahl, P.S. [Los Alamos National Lab., NM (United States)

1996-09-01T23:59:59.000Z

205

Structural Modeling and Molecular Dynamics Simulation of the Actin Filament  

DOE Green Energy (OSTI)

Actin is a major structural protein of the eukaryotic cytoskeleton and enables cell motility. Here, we present a model of the actin filament (F-actin) that not only incorporates the global structure of the recently published model by Oda et al. but also conserves internal stereochemistry. A comparison is made using molecular dynamics simulation of the model with other recent F-actin models. A number of structural determents such as the protomer propeller angle, the number of hydrogen bonds, and the structural variation among the protomers are analyzed. The MD comparison is found to reflect the evolution in quality of actin models over the last 6 years. In addition, simulations of the model are carried out in states with both ADP or ATP bound and local hydrogen-bonding differences characterized.

Splettstoesser, Thomas [University of Heidelberg; Holmes, Kenneth [Max Planck Institute, Heidelberg, Germany; Noe, Frank [DFG Research Center Matheon, FU Berlin, Germany; Smith, Jeremy C [ORNL

2011-01-01T23:59:59.000Z

206

VOYAGER 2 OBSERVES A LARGE DENSITY INCREASE IN THE HELIOSHEATH  

Science Conference Proceedings (OSTI)

Voyager 2 (V2) entered the heliosheath in 2007 August at roughly the same time solar minimum conditions were reaching the outer heliosphere. Soon after crossing the termination shock the solar wind density at Voyager decreased by a factor of two and the temperature decreased by a factor of three. At the beginning of 2011 the plasma density in the heliosheath began to increase and in mid-2012 it was up by more than a factor of two. The temperature rose by about 50% and the speed remained constant, although the flow direction continues to turn tailward. These changes may signal the end of solar minimum conditions at V2 in the heliosheath, although we do not understand why the speed did not decrease. The increased dynamic pressure has lead to an outward movement of the termination shock from its very compressed state at solar minimum.

Richardson, J. D. [Kavli Center for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Wang, C., E-mail: jdr@space.mit.edu, E-mail: cw@spaceweather.ac.cn [State Key Laboratory for Space Weather, Chinese Academy of Sciences, Beijing (China)

2012-11-01T23:59:59.000Z

207

Phase diagram of amorphous solid water: Low-density, high-density, and very-high-density amorphous ices  

E-Print Network (OSTI)

for the understanding of the transformation between the different amorphous ices and the two hypothesized phasesPhase diagram of amorphous solid water: Low-density, high-density, and very-high-density amorphous ices Nicolas Giovambattista,1,2 H. Eugene Stanley,2 and Francesco Sciortino3 1 Department of Chemical

Sciortino, Francesco

208

Explanation of persistent high frequency density structure in coalesced bunches  

SciTech Connect

It has been observed that after the Main Ring rf manipulation of coalescing (where 5 to 13 primary bunches are transferred into a single rf bucket) the new secondary bunch displays evidence of high frequency density structure superimposed on the approximately Gaussian longitudinal bunch length distribution. This structure is persistent over a period of many seconds (hundreds of synchrotron oscillation periods). With the help of multiparticle simulation programs, an explanation of this phenomenon is given in terms of single particle longitudinal phase space dynamics. No coherent effects need be taken into account. 6 refs., 10 figs.

Jackson, Gerald P.

1988-07-01T23:59:59.000Z

209

A Combined 6,7Li NMR and Molecular Dynamics Study of Li Diffusion in Li2TiO3  

SciTech Connect

Understanding lithium diffusion properties in electrode materials is important for designing rechargeable lithium-ion batteries with improved performance. In this work, the lithium dynamics in layered Li2TiO3 were characterized using a combination of 6,7Li nuclear magnetic resonance (NMR) over a wide temperature range (150 to 500 K), and molecular dynamics (MD) simulations. The 7Li static NMR and stimulated echo experiments show slow and partial lithium diffusion in Li2TiO3. The high-field (21.1 T) 6Li magic angle spinning NMR shows a new tetrahedral lithium site along with the three crystallographic octahedral sites in Li2TiO3 sample. MD simulations predict that lithium can occupy a tetrahedral site if two or more vacancies exist in the vicinity, which may result, for example, from the presence of a Ti defect in the LiTi2 layer. 6Li two-dimensional (2D) exchange NMR experiments show evidence of lithium diffusion between the pure Li and LiTi2 layers along the c axis. Although the 2D exchange NMR data is not sensitive to lithium diffusion in the ab plane, MD simulations show that lithium diffusion in the pure Li layer is equally probable. Combining these results, a detailed picture of the lithium diffusion pathways in Li2TiO3 is presented.

Vijayakumar, M.; Kerisit, Sebastien N.; Yang, Zhenguo; Graff, Gordon L.; Liu, Jun; Sears, Jesse A.; Burton, Sarah D.; Rosso, Kevin M.; Hu, Jian Z.

2009-10-27T23:59:59.000Z

210

Oxides having high energy densities  

DOE Patents (OSTI)

Certain disclosed embodiments generally relate to oxide materials having relatively high energy and/or power densities. Various aspects of the embodiments are directed to oxide materials having a structure B.sub.i(M.sub.jY.sub.k)O.sub.2, for example, a structure Li.sub.j(Ni.sub.jY.sub.k)O.sub.2 such as Li(Ni.sub.0.5Mn.sub.0.5)O.sub.2. In this structure, Y represents one or more atoms, each independently selected from the group consisting of alkaline earth metals, transition metals, Group 14 elements, Group 15, or Group 16 elements. In some embodiments, such an oxide material may have an O3 crystal structure, and/or a layered structure such that the oxide comprises a plurality of first, repeating atomic planes comprising Li, and a plurality of second, repeating atomic planes comprising Ni and/or Y.

Ceder, Gerbrand; Kang, Kisuk

2013-09-10T23:59:59.000Z

211

Risk Bounds for Mixture Density Estimation  

E-Print Network (OSTI)

In this paper we focus on the problem of estimating a bounded density using a finite combination of densities from a given class. We consider the Maximum Likelihood Procedure (MLE) and the greedy procedure described by ...

Rakhlin, Alexander

2004-01-27T23:59:59.000Z

212

Bivariate density estimation using BV regularisation  

Science Conference Proceedings (OSTI)

The problem of bivariate density estimation is studied with the aim of finding the density function with the smallest number of local extreme values which is adequate with the given data. Adequacy is defined via Kuiper metrics. The concept of the taut-string ... Keywords: Density estimation, Modality, Regularisation

Andreas Obereder; Otmar Scherzer; Arne Kovac

2007-08-01T23:59:59.000Z

213

Empirical vertical structure of density anomaly in the Gulf of Mexico  

E-Print Network (OSTI)

Climatological vertical structure of density anomaly in the Gulf of Mexico is realistically characterized in a form useful for calibration and/or verification of numerical circulation models, employing a new method that allows variable depth and thermocline ventilation. We do this by local flat bottom dynamic analysis based on the primitive equations referred to an isopycnic coordinate system, so that potential density is treated as a conservative property. A global reference column is constructed for use in a dynamic modal decomposition in terms of local vertical structure functions that integrates seafloor depth and station data in a common spectral representation. The dynamic procedure is followed by joint and simple indirect EOF (empirical orthogonal function) analysis of modal coefficients for the complete data set and for binned subsets of the data. The dominant EOFs resemble dynamic modes, but combinations of dynamic modes are observed in EOFs having small contribution to the total variance. Indirect EOF representation of the data appears to have its greatest implications in the physical interpretation of the dynamic system, specifically in the coupling of dynamic modes.

Current, Carole Louise

1993-01-01T23:59:59.000Z

214

Transport Energy Use and Population Density  

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

Transport Energy Use and Population Density Transport Energy Use and Population Density Speaker(s): Masayoshi Tanishita Date: July 1, 2004 - 10:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Jonathan Sinton After Peter Newman and Jeffrey Kenworthy published "Cities and Automobile Dependence" in 1989, population density was brought to public attention as an important factor to explain transport mobility and energy use. However, several related issues still remain open: Is an increase in population density more effective than rising gas prices in reducing transport energy use? How much does per capita transport energy use change as population density in cities changes? And what kind of factors influence changes in population density? In this presentation, using city-level data in the US, Japan and other countries, the population-density elasticity of

215

Density Currents in Shear Flows-A Two-Fluid Model  

Science Conference Proceedings (OSTI)

This paper develops a two-fluid steady-state model of a density current and its front propagating into a uniformly sheared environmental flow. This model is used to examine the kinematic and dynamic factors that control the depth and propagation ...

Qin Xu

1992-03-01T23:59:59.000Z

216

LA-101( ' X I -E N V~ E N V I R O N M E N T A LS U R V E I L L AA -L O. A -L A -MD U R  

E-Print Network (OSTI)

LA-101( ' X I - E N V~ E N V I R O N M E N T A LS U R V E I L L AA - &.' L_ .---. L O. A - L A - MD U R ,. ,, .". ... , . 1 ` - : . , .i * ?. .& x ` "E!E7...';: s ---- --. -- - + 4. -- sA l a m oN a t i oL a b o r L oA l a m o sN eM e x8 7 `"'l~@fO,,J~@jj~~~~.F=~Of.f~n~~~Y. - w

217

Interlayer Structure and Dynamics of Cl-Bearing Hydrotalcite: Far Infrared Spectroscopy and Molecular Dynamics Modeling  

SciTech Connect

Comparison of the observed far-infrared (FIR) spectrum of Cl--containing hydrotalcite, [Mg3Al(OH)8]Cl?3H2O, with its power spectrum calculated using molecular dynamics (MD) computer simulation provides greatly increased understanding of the structure and vibrational dynamics in the interlayers of layered double hydroxides. The simulation model assumes an ordered Mg3Al arrangement in the octahedral layer and no constraints on the movement of any atoms or on the geometry and symmetry of the simulation supercell. Calculated anisotropic components of the individual atomic power spectra in combination with computed animations of the vibrational modes from normal mode analysis allow for reliable interpretations of the observed spectral bands. For the vibrations related to octahedral cation motions, bands near 145, 180 and 250 cm-1 are due dominantly to Mg vibration in the z direction (perpendicular to the hydroxide layers), Al vibration in the z direction and Mg and Al vibrations in the x-y plane (parallel to the hydroxide layers), respectively. The low frequency vibrational motions of the interlayer are controlled by a network of hydrogen bonds formed among interlayer water molecules, Cl- ions, and the OH groups of the main hydroxide layers. The bands near 40-70 cm-1 are related to the translational motions of interlayer Cl- and H2O in the x-y plane, and the bands near 120 cm-1 and 210 cm-1 are due largely to translational motions of the interlayer species in the z direction. The three librational modes of interlayer water molecules near 390, 450 and 540 cm-1 correspond to twisting, rocking and wagging hindered rotations, respectively. The spectral components of the interlayer Cl- motions are remarkably similar to those of bulk aqueous chloride solutions, reflecting the structural and dynamic similarity of the nearest-neighbor Cl- environments in the interlayer and in solution.

Wang, Jianwei; Kalinichev, Andrey G.; Amonette, James E.; Kirkpatrick, Robert J.

2003-02-01T23:59:59.000Z

218

Cyclotron Resonances in Electron Cloud Dynamics  

SciTech Connect

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lb<< 2pi c/omega c (with lb = bunch length, omega c = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the electron cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor ~;;3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined vertical density"stripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.

Celata, C. M.; Furman, Miguel A.; Vay, J.-L.; Ng, J. S.T.; Grote, D. P.; Pivi, M. T. F.; Wang, L. F.

2009-04-29T23:59:59.000Z

219

Cyclotron Resonances in Electron Cloud Dynamics  

SciTech Connect

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where l{sub b} << 2{pi}{omega}{sub c}, (l{sub b} = bunch duration, {omega}{sub c} = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor {approx} 3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined density 'stripes' of multipactoring found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations, the reason for the bunch-length dependence, and details of the dynamics will be discussed.

Celata, C M; Furman, M A; Vay, J L; Grote, D P; Ng, J T; Pivi, M F; Wang, L F

2009-05-05T23:59:59.000Z

220

Microscopic Description of Nuclear Fission Dynamics  

E-Print Network (OSTI)

We discuss possible avenues to study fission dynamics starting from a time-dependent mean-field approach. Previous attempts to study fission dynamics using the time-dependent Hartree-Fock (TDHF) theory are analyzed. We argue that different initial conditions may be needed to describe fission dynamics depending on the specifics of the fission phenomenon and propose various approaches towards this goal. In particular, we provide preliminary calculations for studying fission following a heavy-ion reaction using TDHF with a density contraint. Regarding prompt muon-induced fission, we also suggest a new approach for combining the time-evolution of the muonic wave function with a microscopic treatment of fission dynamics via TDHF.

A. S. Umar; V. E. Oberacker; J. A. Maruhn; P. -G. Reinhard

2010-03-22T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

Particle beam dynamics | Princeton Plasma Physics Lab  

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

Particle beam dynamics Particle beam dynamics Subscribe to RSS - Particle beam dynamics The study of the physics of charged particle beams and the accelerators that produce them. This cross-disciplinary area intersects with fields such as plasma physics, high-energy density science, and ultra-fast lasers. Premiere issue of "Quest" magazine details PPPL's strides toward fusion energy and advances in plasma science Quest Magazine Summer 2013 Welcome to the premiere issue of Quest, the annual magazine of the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL). Read more about Premiere issue of "Quest" magazine details PPPL's strides toward fusion energy and advances in plasma science Ronald C Davidson Ronald Davidson heads PPPL research on charged particle beam dynamics and

222

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

223

Atomistic modeling of metal surfaces under electric fields: direct coupling of electric fields to a molecular dynamics algorithm  

E-Print Network (OSTI)

The effect of electric fields on metal surfaces is fairly well studied, resulting in numerous analytical models developed to understand the mechanisms of ionization of surface atoms observed at very high electric fields, as well as the general behavior of a metal surface in this condition. However, the derivation of analytical models does not include explicitly the structural properties of metals, missing the link between the instantaneous effects owing to the applied field and the consequent response observed in the metal surface as a result of an extended application of an electric field. In the present work, we have developed a concurrent electrodynamic–molecular dynamic model for the dynamical simulation of an electric-field effect and subsequent modification of a metal surface in the framework of an atomistic molecular dynamics (MD) approach. The partial charge induced on the surface atoms by the electric field is assessed by applying the classical Gauss law. The electric forces acting on the partially...

Djurabekova, Flyura; Pohjonen, Aarne; Nordlund, Kai

2011-01-01T23:59:59.000Z

224

High Density Fuel Development for Research Reactors  

SciTech Connect

An international effort to develop, qualify, and license high and very high density fuels has been underway for several years within the framework of multi-national RERTR programs. The current development status is the result of significant contributions from many laboratories, specifically CNEA in Argentina, AECL in Canada, CEA in France, TUM in Germany, KAERI in Korea, VNIIM, RDIPE, IPPE, NCCP and RIARR in Russia, INL, ANL and Y-12 in USA. These programs are mainly engaged with UMo dispersion fuels with densities from 6 to 8 gU/cm3 (high density fuel) and UMo monolithic fuel with density as high as 16 gU/cm3 (very high density fuel). This paper, mainly focused on the French & US programs, gives the status of high density UMo fuel development and perspectives on their qualification.

Daniel Wachs; Dennis Keiser; Mitchell Meyer; Douglas Burkes; Curtis Clark; Glenn Moore; Jan-Fong Jue; Totju Totev; Gerard Hofman; Tom Wiencek; Yeon So Kim; Jim Snelgrove

2007-09-01T23:59:59.000Z

225

The Quantum Energy Density: Improved E  

Science Conference Proceedings (OSTI)

We establish a physically meaningful representation of a quantum energy density for use in Quantum Monte Carlo calculations. The energy density operator, dened in terms of Hamiltonian components and density operators, returns the correct Hamiltonian when integrated over a volume containing a cluster of particles. This property is demonstrated for a helium-neon \\gas," showing that atomic energies obtained from the energy density correspond to eigenvalues of isolated systems. The formation energies of defects or interfaces are typically calculated as total energy dierences. Using a model of delta-doped silicon (where dopant atoms form a thin plane) we show how interfacial energies can be calculated more eciently with the energy density, since the region of interest is small. We also demonstrate how the energy density correctly transitions to the bulk limit away from the interface where the correct energy is obtainable from a separate total energy calculation.

Krogel, Jaron [University of Illinois, Urbana-Champaign; Yu, Min [Lawrence Berkeley National Laboratory (LBNL); Kim, Jeongnim [ORNL; Ceperley, David M. [University of Illinois, Urbana-Champaign

2013-01-01T23:59:59.000Z

226

Considering Air Density in Wind Power Production  

E-Print Network (OSTI)

In the wind power production calculations the air density is usually considered as constant in time. Using the CIPM-2007 equation for the density of moist air as a function of air temperature, air pressure and relative humidity, we show that it is worth taking the variation of the air density into account, because higher accuracy can be obtained in the calculation of the power production for little effort.

Zénó Farkas

2011-03-11T23:59:59.000Z

227

Some challenges for Nuclear Density Functional Theory  

E-Print Network (OSTI)

We discuss some of the challenges that the DFT community faces in its quest for the truly universal energy density functional applicable over the entire nuclear chart.

T. Duguet; K. Bennaceur; T. Lesinski; J. Meyer

2006-06-20T23:59:59.000Z

228

Application of Precession Electron Diffraction in Density ...  

Science Conference Proceedings (OSTI)

In this paper, GND density calculations obtained using SEM-based EBSD and transmission electron microscope-based PED techniques in ?+? titanium alloys ...

229

MECHANICALLY ROBUST, ELECTRICALLY CONDUCTIVE ULTRALOW-DENSITY ...  

A method of making a mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogel, including the steps of dispersing nanotubes in an ...

230

Betatron radiation from density tailored plasmas  

E-Print Network (OSTI)

Betatron radiation from density tailored plasmas K. Tathe resulting betatron radiation spectrum can therefore bepro?le, the betatron radiation emitted by theses electrons

Ta Phuoc, Kim

2010-01-01T23:59:59.000Z

231

3-D capacitance density imaging system  

DOE Patents (OSTI)

A three-dimensional capacitance density imaging of a gasified bed or the like in a containment vessel is achieved using a plurality of electrodes provided circumferentially about the bed in levels and along the bed in channels. The electrodes are individually and selectively excited electrically at each level to produce a plurality of current flux field patterns generated in the bed at each level. The current flux field patterns are suitably sensed and a density pattern of the bed at each level determined. By combining the determined density patterns at each level, a three-dimensional density image of the bed is achieved. 7 figs.

Fasching, G.E.

1988-03-18T23:59:59.000Z

232

High Energy Density Secondary Lithium Batteries  

High Energy Density Secondary Lithium Batteries Note: The technology described above is an early stage opportunity. Licensing rights to this intellectual property may

233

Dynamics of colloidal particles in ice  

E-Print Network (OSTI)

We use X-ray Photon Correlation Spectroscopy (XPCS) to probe the dynamics of colloidal particles in polycrystalline ice. During freezing, the dendritic ice morphology and rejection of particles from the ice created regions of high-particle-density, where some of the colloids were forced into contact and formed disordered aggregates. We find that the particles in these high density regions underwent ballistic motion coupled with both stretched and compressed exponential decays of the intensity autocorrelation function, and that the particles' characteristic velocity increased with temperature. We explain this behavior in terms of ice grain boundary migration.

Melissa Spannuth; S. G. J. Mochrie; S. S. L. Peppin; J. S. Wettlaufer

2010-12-31T23:59:59.000Z

234

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

235

High density laser-driven target  

DOE Patents (OSTI)

A high density target for implosion by laser energy composed of a central quantity of fuel surrounded by a high-Z pusher shell with a low-Z ablator-pusher shell spaced therefrom forming a region filled with low-density material.

Lindl, John D. (San Ramon, CA)

1981-01-01T23:59:59.000Z

236

Laser light absorption with density profile modifications  

SciTech Connect

Two-dimensional computer simulations studied plasma heating by electron plasma waves. The results emphasize the importance of nonlinear steepening of the density profile near the critical density. A typical simulation result is presented in order to illustrate these profile modifications. It is shown that large dc magnetic field generation is an inherent property of the absorption of obliquely-incident light. (MOW)

Kruer, W.; Valeo, E.; Estabrook, K.; Langdon, B.; Lasinski, B.

1974-12-01T23:59:59.000Z

237

Estimate of dielectric density using spectroscopic ellipsometry  

Science Conference Proceedings (OSTI)

The optical dielectric functions for hafnium oxide and hafnium silicate films were extracted from spectroscopic ellipsometry measurements and the density then calculated using a previously proposed method. The values obtained were then compared to those ... Keywords: Density, Gadolinium oxide, Hafnium silicate, Medium energy ion scattering, Spectroscopic ellipsometry, X-ray reflectometry

W. Davey; O. Buiu; M. Werner; I. Z. Mitrovic; S. Hall; P. Chalker

2009-07-01T23:59:59.000Z

238

Probing the hydration structure of polarizable halides: a multi-edge XAFS and molecular dynamics study of the iodide anion.  

DOE Green Energy (OSTI)

A comprehensive analysis of the H2O structure about aqueous iodide (I-) is reported from molecular dynamics (MD) simulation and x-ray absorption fine structure (XAFS) measurements. XAFS spectra from the iodide K-, L1-, and L3- edges were co-refined to establish the complete structure of the first hydration shell about aqueous I-. The results show approximately 6.3 water molecules located at I-H and I-O distances of 2.65 Å and 3.50 Å, respectively. Whereas the I-O bond is moderately disordered (Debye Waller factor, ?2 = 0.017 Å2) due to the relatively low charge-to-ion radius ratio, the I-H interaction shows even higher disorder (?2 = 0.036 Å2) due to the variable angular orientation of water at the ion surface. Molecular dynamics simulations employing both DFT (+dispersion) and classical potentials generate quite similar structures and they both agree to a large extent with the structure from the experimental XAFS. However the DFT-MD simulations provide a description of molecular structure that is more consistent with the XAFS experiment data. We employ a molecular anaylsis in which we incrementally evaluate the structural contributions from each of the nearest-neighbor water molecules about the iodide to provide a clear picture of the hydrated structure. For the DFT description of molecular interaction, a water molecule in the first shell has more freedom to rotate about the O atom when compared to motions resulting from a classical potential. Further, the hydrogen bonding of first-shell water with the second shell water establishes an strong ordering of the water about I- surface leading to characteristic O-I-O angles of 79 and 142°. This ordering, in addition to the higher coordination number leads to a more symmetric solvation from the DFT-MD configurations relative to the classical potential simulation.

Fulton, John L.; Schenter, Gregory K.; Baer, Marcel; Mundy, Christopher J.; Dang, Liem X.; Balasubramanian, Mahalingam

2010-10-14T23:59:59.000Z

239

Density of Spray-Formed Materials  

SciTech Connect

Spray Forming is an advanced materials processing technology that transforms molten metal into a near-net-shape solid by depositing atomized droplets onto a substrate. Depending on the application, the spray-formed material may be used in the as-deposited condition or it may undergo post-deposition processing. Regardless, the density of the as-deposited material is an important issue. Porosity is detrimental because it can significantly reduce strength, toughness, hardness and other properties. While it is not feasible to achieve fully-dense material in the as-deposited state, density greater than 99% of theoretical density is possible if the atomization and impact conditions are optimized. Thermal conditions at the deposit surface and droplet impact angle are key processing parameters that influence the density of the material. This paper examines the factors that contribute to porosity formation during spray forming and illustrates that very high as-deposited density is achieved by optimizing processing parameters.

Kevin M. McHugh; Volker Uhlenwinkel; Nils Ellendr

2008-06-01T23:59:59.000Z

240

Contents 1 Molecular Dynamics Simulation of Argon 1  

E-Print Network (OSTI)

1.1 Simple model of interacting Argon atoms........................... 2 2 A simple MD program 4 2.1 Newton’s Equations of Motion................................ 6

unknown authors

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

In Situ Observation on Dislocation Dynamics in Nanocrystalline and ...  

Science Conference Proceedings (OSTI)

This talk will cover in situ TEM and MD modeling on the nanoscale ... Structures and Properties of Higher Pressure Combustion Driven Compacted ...

242

GyPSuM: A Detailed Tomographic Model of Mantle Density and Seismic Wave Speeds  

SciTech Connect

GyPSuM is a tomographic model fo mantle seismic shear wave (S) speeds, compressional wave (P) speeds and detailed density anomalies that drive mantle flow. the model is developed through simultaneous inversion of seismic body wave travel times (P and S) and geodynamic observations while considering realistic mineral physics parameters linking the relative behavior of mantle properties (wave speeds and density). Geodynamic observations include the (up to degree 16) global free-air gravity field, divergence of the tectonic plates, dynamic topography of the free surface, and the flow-induced excess ellipticity of the core-mantle boundary. GyPSuM is built with the philosophy that heterogeneity that most closely resembles thermal variations is the simplest possible solution. Models of the density field from Earth's free oscillations have provided great insight into the density configuration of the mantle; but are limited to very long-wavelength solutions. Alternatively, simply scaling higher resolution seismic images to density anomalies generates density fields that do not satisfy geodynamic observations. The current study provides detailed density structures in the mantle while directly satisfying geodynamic observations through a joint seismic-geodynamic inversion process. Notable density field observations include high-density piles at the base of the superplume structures, supporting the fundamental results of past normal mode studies. However, these features are more localized and lower amplitude than past studies would suggest. When we consider all seismic anomalies in GyPSuM, we find that P and S-wave speeds are strongly correlated throughout the mantle. However, correlations between the high-velocity S zones in the deep mantle ({approx} 2000 km depth) and corresponding P-wave anomalies are very low suggesting a systematic divergence from simplified thermal effects in ancient subducted slab anomalies. Nevertheless, they argue that temperature variations are the primary cause of P-wave, S-wave, and density anomalies in the mantle.

Simmons, N A; Forte, A M; Boschi, L; Grand, S P

2010-03-30T23:59:59.000Z

243

The molecular dynamics simulation of ion-induced ripple growth  

Science Conference Proceedings (OSTI)

The wavelength-dependence of ion-sputtering induced growth of repetitive nanostructures, such as ripples has been studied by molecular dynamics (MD) simulations in Si. The early stage of the ion erosion driven development of ripples has been simulated on prepatterned Si stripes with a wavy surface. The time evolution of the height function and amplitude of the sinusoidal surface profile has been followed by simulated ion-sputtering. According to Bradley-Harper (BH) theory, we expect correlation between the wavelength of ripples and the stability of them. However, we find that in the small ripple wavelength ({lambda}) regime BH theory fails to reproduce the results obtained by molecular dynamics. We find that at short wavelengths ({lambda}35 nm is stabilized in accordance with the available experimental results. According to the simulations, few hundreds of ion impacts in {lambda} long and few nanometers wide Si ripples are sufficient for reaching saturation in surface growth for for {lambda}>35 nm ripples. In another words, ripples in the long wavelength limit seems to be stable against ion-sputtering. A qualitative comparison of our simulation results with recent experimental data on nanopatterning under irradiation is attempted.

Suele, P. [Research Institute for Technical Physics and Materials Science, Konkoly Thege u. 29-33, 1125 Budapest (Hungary); Heinig, K.-H. [Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, P.O. Box 51 01 19, 01314 Dresden (Germany)

2009-11-28T23:59:59.000Z

244

Low density, resorcinol-formaldehyde aerogels  

DOE Patents (OSTI)

The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer clusters. The covalent crosslinking of these clusters produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density [<=]100 mg/cc; cell size [<=]0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 [angstrom]. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.

Pekala, R.W.

1989-10-10T23:59:59.000Z

245

Low density, resorcinol-formaldehyde aerogels  

DOE Patents (OSTI)

The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer clusters''. The covalent crosslinking of these clusters'' produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density {le}100 mg/cc; cell size {le}0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 A{degrees}. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron. 1 ref., 1 tab.

Pekala, R.W.

1989-09-12T23:59:59.000Z

246

Low density, resorcinol-formaldehyde aerogels  

DOE Patents (OSTI)

The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer "clusters". The covalent crosslinking of these "clusters" produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density .ltoreq.100 mg/cc; cell size .ltoreq.0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 .ANG.. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.

Pekala, Richard W. (Pleasant Hill, CA)

1989-01-01T23:59:59.000Z

247

Low density, resorcinol-formaldehyde aerogels  

DOE Patents (OSTI)

The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer "Clusters". The covalent crosslinking of these "clusters" produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density.ltoreq.100 mg/cc; cell size .ltoreq.0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100.circle.. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.

Pekala, Richard W. (Pleasant Hill, CA)

1991-01-01T23:59:59.000Z

248

Electronic Structure Measurement of Solid Density Plasmas using X-Ray Scattering  

DOE Green Energy (OSTI)

We present an improved analytical expression for the x-ray dynamic structure factor from a dense plasma which includes the effects of weakly bound electrons. This result can be applied to describe scattering from low to moderate Z plasmas, and it covers the entire range of plasma conditions that can be found in inertial confinement fusion experiments, from ideal to degenerate up to moderately coupled systems. We use our theory to interpret x-ray scattering experiments from solid density carbon plasma and to extract accurate measurements of electron temperature, electron density and charge state. We use our experimental results to validate various equation-of-state models for carbon plasmas.

Gregori, G; Glenzer, S H; Rogers, F J; Landen, O L; Blancard, C; Faussurier, G; Renaudin, P; Kuhlbrodt, S; Redmer, R

2003-08-23T23:59:59.000Z

249

Investigation of the Electronic Structure of Solid Density Plasmas by X-Ray Scattering  

DOE Green Energy (OSTI)

We present an improved analytical expression for the x-ray dynamic structure factor from a dense plasma which includes the effects of weakly bound electrons. This result can be applied to describe scattering from low to moderate Z plasmas, and it covers the entire range of plasma conditions that can be found in inertial confinement fusion experiments, from ideal to degenerate up to moderately coupled systems. We use our theory to interpret x-ray scattering experiments from solid density carbon plasma and to extract accurate measurements of electron temperature, electron density and charge state. We use our experimental results to validate various equation-of-state models for carbon plasmas.

Gregori, G; Glenzer, S H; Forest, F J; Kuhlbrodt, S; Redmer, R; Faussurier, G; Blancard, C; Renaudin, P; Landen, O L

2003-05-19T23:59:59.000Z

250

Pion optical potential with. delta. dynamics  

SciTech Connect

A pion optical potential is constructed which incorporates the ..delta.. dynamics found to be important in ..delta..-hole analyses of pion scattering from light nuclei. These dynamics include ..delta.. propagation, binding and Pauli blocking, and a ..delta.. spreading potential. We employ a local density approximation for the medium-modified ..delta.. propagator, resulting in a computationally flexible tool for the analysis of pion-nucleus data. We reproduce the ..delta..-hole results for ..pi..-/sup 16/O scattering satisfactorily. Elastic ..pi../sup + -/-/sup 208/Pb scattering is described very well with the same strongly damping spreading potential found for light nuclei. The pion wave functions in the medium are substantially modified by the ..delta.. dynamics.

Karaoglu, B.; Moniz, E.J.

1986-03-01T23:59:59.000Z

251

Velocity Probability Density Functions for Oceanic Floats  

Science Conference Proceedings (OSTI)

Probability density functions (PDFs) of daily velocities from subsurface floats deployed in the North Atlantic and equatorial Atlantic Oceans are examined. In general, the PDFs are approximately Gaussian for small velocities, but with significant ...

Annalisa Bracco; J. H. LaCasce; Antonello Provenzale

2000-03-01T23:59:59.000Z

252

wave power density | OpenEI  

Open Energy Info (EERE)

power density power density Dataset Summary Description This project estimates the naturally available and technically recoverable U.S. wave energy resources, using a 51-month Wavewatch III hindcast database developed especially for this study by National Oceanographic and Atmospheric Administration's (NOAA's) National Centers for Environmental Prediction. For total resource estimation, wave power density in terms of kilowatts per meter is aggregated across a unit diameter circle. Source Electric Power Research Institute (EPRI) Date Released December 05th, 2011 (2 years ago) Date Updated Unknown Keywords EPRI MHK NREL ocean Virginia Tech wave wave power density Data application/pdf icon Download Full Report (pdf, 8.8 MiB) Quality Metrics Level of Review Some Review Comment

253

Definition: Rock Density | Open Energy Information  

Open Energy Info (EERE)

in crustal rocks. Rock density is a physical characteristic that is governed by the chemical composition (in situ minerals) and pore spaces of a specific rock or rock type.1...

254

High density load bearing insulation peg  

DOE Patents (OSTI)

A high density peg is disclosed which can support a large load and exhibits excellent thermal resistance produced by a method wherein the peg is made in compliance with specified conditions of time, temperature and pressure. 4 figs.

Nowobilski, J.J.; Owens, W.J.

1985-01-29T23:59:59.000Z

255

Velocity Probability Density Functions from Altimetry  

Science Conference Proceedings (OSTI)

Probability density functions (pdfs) are employed to evaluate the distribution of velocities in the global ocean. This study computes pdfs of ocean surface velocity using altimetric data from the TOPEX/Poseidon satellite. Results show that the ...

Sarah T. Gille; Stefan G. Llewellyn Smith

2000-01-01T23:59:59.000Z

256

Density controlled carbon nanotube array electrodes  

DOE Patents (OSTI)

CNT materials comprising aligned carbon nanotubes (CNTs) with pre-determined site densities, catalyst substrate materials for obtaining them and methods for forming aligned CNTs with controllable densities on such catalyst substrate materials are described. The fabrication of films comprising site-density controlled vertically aligned CNT arrays of the invention with variable field emission characteristics, whereby the field emission properties of the films are controlled by independently varying the length of CNTs in the aligned array within the film or by independently varying inter-tubule spacing of the CNTs within the array (site density) are disclosed. The fabrication of microelectrode arrays (MEAs) formed utilizing the carbon nanotube material of the invention is also described.

Ren, Zhifeng F. (Newton, MA); Tu, Yi (Belmont, MA)

2008-12-16T23:59:59.000Z

257

Separation of carbon nanotubes in density gradients  

DOE Patents (OSTI)

The separation of single-walled carbon nanotubes (SWNTs), by chirality and/or diameter, using centrifugation of compositions of SWNTs in and surface active components in density gradient media.

Hersam, Mark C. (Evanston, IL); Stupp, Samuel I. (Chicago, IL); Arnold, Michael S. (Northbrook, IL)

2012-02-07T23:59:59.000Z

258

Separation of carbon nanotubes in density gradients  

DOE Patents (OSTI)

The separation of single-walled carbon nanotubes (SWNTs), by chirality and/or diameter, using centrifugation of compositions of SWNTs in and surface active components in density gradient media.

Hersam, Mark C. (Evanston, IL); Stupp, Samuel I. (Chicago, IL); Arnold, Michael S. (Northbrook, IL)

2010-02-16T23:59:59.000Z

259

High density load bearing insulation peg  

DOE Patents (OSTI)

A high density peg which can support a large load and exhibits excellent thermal resistance produced by a method wherein the peg is made in compliance with specified conditions of time, temperature and pressure.

Nowobilski, Jeffert J. (Orchard Park, NY); Owens, William J. (Kenmore, NY)

1985-01-01T23:59:59.000Z

260

Local Atomic Density of Microporous Carbons  

DOE Green Energy (OSTI)

We investigated the structure of two disordered carbons: activated carbon fibers (ACF) and ultramicroporous carbon (UMC). These carbons have highly porous structure with large surface areas and consequently low macroscopic density that should enhance adsorption of hydrogen. We used the atomic pair distribution function to probe the local atomic arrangements. The results show that the carbons maintain an in-plane local atomic structure similar to regular graphite, but the stacking of graphitic layers is strongly disordered. Although the local atomic density of these carbons is lower than graphite, it is only {approx}20% lower and is much higher than the macroscopic density due to the porosity of the structure. For this reason, the density of graphene sheets that have optimum separation for hydrogen adsorption is lower than anticipated.

Dmowski, Wojtek; Contescu, Cristian I.; Llobet, Anna; Gallego, Nidia C.; Egami, Takeskhi (Tennessee-K); (ORNL); (LANL)

2012-07-12T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

Support for the delisting of decontaminated liquid chemical surety materials as listed hazardous waste from specific sources (state) MD02 in COMAR 10. 51. 02. 16-1. Technical report, December 1987-February 1988  

SciTech Connect

Maryland recently enacted regulations that listed decontaminated residues of certain chemical warfare agents as hazardous wastes. The State would consider delisting if the Army document the effects of its decontamination procedures. Army specialists at U.S. Army Chemical Research, Development and Engineering Center (CRDEC), Aberdeen Proving Ground, MD, have had exhaustive experience in this area since 1918 when chemical agents were first used in combat in World War I. Competence accrued during this 70-year legacy includes destruction of laboratory and training wastes, combat decontamination, and largescale demilitarization of unserviceable and obsolete agent-filled munitions. The facts and circumstances enumerated in this document indicate that current decontamination practices are safe, scientifically valid, and result in the total destruction of agents in questions.

Durst, H.D.; Sarver, E.W.; Yurow, H.W.; Beaudry, W.T.; D'Eramo, P.A.

1988-11-01T23:59:59.000Z

262

Probability density function transformation using seeded localized averaging  

SciTech Connect

Seeded Localized Averaging (SLA) is a spectrum acquisition method that averages pulse-heights in dynamic windows. SLA sharpens peaks in the acquired spectra. This work investigates the transformation of the original probability density function (PDF) in the process of applying SLA procedure. We derive an analytical expression for the resulting probability density function after an application of SLA. In addition, we prove the following properties: 1) for symmetric distributions, SLA preserves both the mean and symmetry. 2) for uni-modal symmetric distributions, SLA reduces variance, sharpening the distributions peak. Our results are the first to prove these properties, reinforcing past experimental observations. Specifically, our results imply that in the typical case of a spectral peak with Gaussian PDF the full width at half maximum (FWHM) of the transformed peak becomes narrower even with averaging of only two pulse-heights. While the Gaussian shape is no longer preserved, our results include an analytical expression for the resulting distribution. Examples of the transformation of other PDFs are presented. (authors)

Dimitrov, N. B. [Operations Research Dept., Naval Postgraduate School, Monterey, CA 93943 (United States); Jordanov, V. T. [Yantel, LLC, Santa Fe, NM 87508 (United States)

2011-07-01T23:59:59.000Z

263

Capacitance-level/density monitor for fluidized-bed combustor  

DOE Patents (OSTI)

A multiple segment three-terminal type capacitance probe with segment selection, capacitance detection and compensation circuitry and read-out control for level/density measurements in a fluidized-bed vessel is provided. The probe is driven at a high excitation frequency of up to 50 kHz to sense quadrature (capacitive) current related to probe/vessel capacitance while being relatively insensitive to the resistance current component. Compensation circuitry is provided for generating a negative current of equal magnitude to cancel out only the resistive component current. Clock-operated control circuitry separately selects the probe segments in a predetermined order for detecting and storing this capacitance measurement. The selected segment acts as a guarded electrode and is connected to the read-out circuitry while all unselected segments are connected to the probe body, which together form the probe guard electrode. The selected probe segment capacitance component signal is directed to a corresponding segment channel sample and hold circuit dedicated to that segment to store the signal derived from that segment. This provides parallel outputs for display, computer input, etc., for the detected capacitance values. The rate of segment sampling may be varied to either monitor the dynamic density profile of the bed (high sampling rate) or monitor average bed characteristics (slower sampling rate).

Fasching, George E. (Morgantown, WV); Utt, Carroll E. (Morgantown, WV)

1982-01-01T23:59:59.000Z

264

Transient Dynamics of Nonsymmetric Perturbations versus Symmetric Instability in Baroclinic Zonal Shear Flows  

Science Conference Proceedings (OSTI)

The linear dynamics of symmetric and nonsymmetric perturbations in unbounded zonal inviscid flows with a constant vertical shear of velocity, when a fluid is incompressible and density is stably stratified along the vertical and meridional ...

G. R. Mamatsashvili; V. S. Avsarkisov; G. D. Chagelishvili; R. G. Chanishvili; M. V. Kalashnik

2010-09-01T23:59:59.000Z

265

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. íStröM; R. D. Bell

2000-03-01T23:59:59.000Z

266

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...

267

Reduced density matrix hybrid approach: Application to electronic energy transfer  

SciTech Connect

Electronic energy transfer in the condensed phase, such as that occurring in photosynthetic complexes, frequently occurs in regimes where the energy scales of the system and environment are similar. This situation provides a challenge to theoretical investigation since most approaches are accurate only when a certain energetic parameter is small compared to others in the problem. Here we show that in these difficult regimes, the Ehrenfest approach provides a good starting point for a dynamical description of the energy transfer process due to its ability to accurately treat coupling to slow environmental modes. To further improve on the accuracy of the Ehrenfest approach, we use our reduced density matrix hybrid framework to treat the faster environmental modes quantum mechanically, at the level of a perturbative master equation. This combined approach is shown to provide an efficient and quantitative description of electronic energy transfer in a model dimer and the Fenna-Matthews-Olson complex and is used to investigate the effect of environmental preparation on the resulting dynamics.

Berkelbach, Timothy C.; Reichman, David R. [Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027 (United States); Markland, Thomas E. [Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305 (United States)

2012-02-28T23:59:59.000Z

268

First Results of the LHC Longitudinal Density Monitor  

Science Conference Proceedings (OSTI)

The Large Hadron Collider (LHC) at CERN is the world's largest particle accelerator. It is designed to accelerate and collide protons or heavy ions up to the center-of-mass energies of 14 TeV. Knowledge of the longitudinal distribution of particles is important for various aspects of accelerator operation, in particular to check the injection quality and to measure the proportion of charge outside the nominally filled bunches during the physics periods. In order to study this so-called ghost charge at levels very much smaller than the main bunches, a longitudinal profile measurement with a very high dynamic range is needed. A new detector, the LHC Longitudinal Density Monitor (LDM) is a single-photon counting system measuring synchrotron light by means of an avalanche photodiode detector. The unprecedented energies reached in the LHC allow synchrotron light diagnostics to be used with both protons and heavy ions. A prototype was installed during the 2010 LHC run and was able to longitudinally profile the whole ring with a resolution close to the target of 50 ps. On-line correction for the effects of the detector deadtime, pile-up and afterpulsing allow a dynamic range of 105 to be achieved. First measurements with the LDM are presented here along with an analysis of its performance and an outlook for future upgrades.

Jeff, A.; /CERN /Liverpool U.; Boccardi, A.; /CERN; Bravin, E.; /CERN; Fisher, A.S.; /SLAC; Lefevre, T.; /CERN; Rabiller, A.; /CERN; Roncarolo, F.; /CERN; Welsch, C.P.; /Liverpool U. /Cockcroft Inst. Accel. Sci. Tech.

2012-04-19T23:59:59.000Z

269

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

270

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

271

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

272

Density logging and density of rocks in Rainier Mesa Area, Nevada Test Site  

SciTech Connect

Density logs from all 35 vertical drill holes in the Rainier Mesa area in which logs were obtained were evaluated and the distribution of densities of units in the geologic section was derived. Densities were obtained in only 10 holes in which calibrated logging tools had been run. The logs from an additional 10 holes were calibrated with core. Densities vary from nearly 1 g/cc in tunnel bed 5 to over 2.8 g/cc in the dolomitic rocks. Log densities were found to agree well with core data in those subunits (chiefly within tunnel beds 3 and 4) where an adequate number of core measurements were available for comparison. Lithologic correlations based on density log signatures were found to extend for more than 8 km in several units and subunits in the area. Although the volcanic rocks in the Rainier Mesa area are comprised of a wider spectrum of minerals than the petroliferous rocks generally involved in most commercial logging applications, grain density may be estimated with good accuracy with only a knowledge of glass and zeolite content. The variability of the Z/A ratio of the matrix in these volcanic rocks is also negligible compared to the value of 0.5 generally assumed in density logging. However, due to the assumptions made concerning the Z/A of water in deriving the output of commercial density tools, one should be aware of the errors inherent in assuming that recorded log densities are true densities. These errors are normally small, being less than 3 percent for compensated limestone'' tools and 2 percent for tools which output electron density. 35 refs., 25 figs., 12 tabs.

Carroll, R.D.

1989-01-01T23:59:59.000Z

273

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

274

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.

275

Precise and Accurate Density Determination of Explosives Using Hydrostatic Weighing  

SciTech Connect

Precise and accurate density determination requires weight measurements in air and water using sufficiently precise analytical balances, knowledge of the densities of air and water, knowledge of thermal expansions, availability of a density standard, and a method to estimate the time to achieve thermal equilibrium with water. Density distributions in pressed explosives are inferred from the densities of elements from a central slice.

B. Olinger

2005-07-01T23:59:59.000Z

276

High-Energy-Density Plasmas, Fluids  

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

High-Energy-Density Plasmas, Fluids High-Energy-Density Plasmas, Fluids /science-innovation/_assets/images/icon-science.jpg High-Energy-Density Plasmas, Fluids National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. TRIDENT target chamber Sasi Palaniyappan, right, and Rahul Shah left inside a target chamber where the TRIDENT short pulse laser is aimed at a very thin diamond- foil target, a fraction of a micrometer thick. The laser delivers a power on target of 150 Terawatts focused into a 7 micrometer spot, yielding laser brilliance over 100 times more intense than needed to make the target electrons fully relativistic. These experiments test novel methods of producing intense

277

Low density, resorcinol-formaldehyde aerogels  

DOE Patents (OSTI)

The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer ''clusters''. The covalent crosslinking of these ''clusters'' produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density less than or equal to100 mg/cc; cell size less than or equal to0.1 microns). The aerogels are transparent,dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 A/degree/. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron. 1 fig., 1 tab.

Pekala, R.W.

1988-05-26T23:59:59.000Z

278

Fabrication of low density ceramic material  

DOE Patents (OSTI)

A precursor mixture and a method of making a low-density ceramic structural material are disclosed. The precursor mixture includes hollow microballoons, typically made of glass, together with a cementing agent capable of being cured by microwave irradiation. A preferred cementing agent is liquid hydrated potassium silicate, which is mixed with the glass microballoons to form a slurry. Upon irradiation the potassium silicate is dehydrated to form a solid porous matrix in which the microballoons are evenly distributed. Ground glass or other filling agents may be included in the slurry to enhance the properties of the final product. Low-density structural ceramics having densities on the order of 0.1 to 0.3 are obtained.

Meek, T.T.; Blake, R.D.; Sheinberg, H.

1985-01-01T23:59:59.000Z

279

Radiation in molecular dynamic simulations  

DOE Green Energy (OSTI)

Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of Megabars to thousands of Gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The new technique passes a key test: it relaxes to a blackbody spectrum for a plasma in local thermodynamic equilibrium. This new tool also provides a method for assessing the accuracy of energy and momentum exchange models in hot dense plasmas. As an example, we simulate the evolution of non-equilibrium electron, ion, and radiation temperatures for a hydrogen plasma using the new molecular dynamics simulation capability.

Glosli, J; Graziani, F; More, R; Murillo, M; Streitz, F; Surh, M

2008-10-13T23:59:59.000Z

280

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

Note: This page contains sample records for the topic "dynamics md density" 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

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

282

Low density, microcellular foams, preparation, and articles  

DOE Patents (OSTI)

A microcellular low-density foam of poly(4-methyl-1-pentene) particularly useful for forming targets for inertial confinement fusion has been developed. Articles made from the foam have been machined to tolerances of 0.0001 inch, although the densities of the fragile foam are low (about 10 to about 100 mg/cc) and the cell sizes are small (about 10 to about 30 ..mu..m). Methods for forming the foam and articles are given. The yield strength of the foam of the invention is higher than was obtained in other structures of this same material.

Young, A.T.

1982-03-03T23:59:59.000Z

283

Thermal Density Functional Theory in Context  

E-Print Network (OSTI)

This chapter introduces thermal density functional theory, starting from the ground-state theory and assuming a background in quantum mechanics and statistical mechanics. We review the foundations of density functional theory (DFT) by illustrating some of its key reformulations. The basics of DFT for thermal ensembles are explained in this context, as are tools useful for analysis and development of approximations. We close by discussing some key ideas relating thermal DFT and the ground state. This review emphasizes thermal DFT's strengths as a consistent and general framework.

Pribram-Jones, Aurora; Gross, E K U; Burke, Kieron

2013-01-01T23:59:59.000Z

284

NEUTRON DENSITY CONTROL IN A NEUTRONIC REACTOR  

DOE Patents (OSTI)

The method and means for controlling the neutron density in a nuclear reactor is described. It describes the method and means for flattening the neutron density distribution curve across the reactor by spacing the absorbing control members to varying depths in the central region closer to the center than to the periphery of the active portion of the reactor to provide a smaller neutron reproduction ratio in the region wherein the members are inserted, than in the remainder of the reactor thereby increasing the over-all potential power output.

Young, G.J.

1959-06-30T23:59:59.000Z

285

Dark Energy Density in Brane World  

E-Print Network (OSTI)

We present a possible explanation to the tiny positive cosmological constant under the frame of AdS$_5$ spacetime embedded by a dS$_4$ brane. We calculate the dark energy density by summing the zero point energy of massive scalar fields in AdS$_5$ spacetime. Under the assumption that the radius of AdS$_5$ spacetime is of the same magnitude as the radius of observable universe, the dark energy density in dS$_4$ brane is obtained, which is smaller than the observational value. The reasons are also discussed.

Hai-Bao Wen; Xin-Bing Huang

2005-02-08T23:59:59.000Z

286

Corrosion Study of Fe in a Stagnant Liquid Pb by Molecular Dynamics Methods  

Science Conference Proceedings (OSTI)

It has been investigated theoretically the corrosion phenomena of iron (Fe) in liquid lead (Pb) by molecular dynamics methods. The corrosion phenomena was regarded as a diffusion process in which the Fe atoms of bulk material spreading into a liquid Pb. The D diffusion coefficient of the corrosion was calculated. We reported the self-diffusion coefficient of Fe in liquid Pb is D{sub MD} (750 deg.) = 2.59x10{sup -9}m{sup 2}/s. This is in the range of (1.31-5.75)x10{sup -9} m{sup 2}/s from literature and also closed to D{sub Robertson}(750 deg. C) = 2.74x10{sup -9} m{sup 2}/s based on the Robertson curve.

Arkundato, A. [Physics Dept, Faculty of Math. And Natural Sciences, Institut Teknologi Bandung, Indonesia Jl.Ganesha 10, Bandung 40132 (Indonesia); Physics Dept, Faculty of Math. And Natural Sciences, Universitas Jember (Indonesia); Suud, Zaki; Abdullah, Mikrajudin [Physics Dept, Faculty of Math. And Natural Sciences, Institut Teknologi Bandung, Indonesia Jl.Ganesha 10, Bandung 40132 (Indonesia)

2010-06-22T23:59:59.000Z

287

Dynamic Simulation of DFIG Wind Turbines on FPGA Boards  

E-Print Network (OSTI)

Dynamic Simulation of DFIG Wind Turbines on FPGA Boards Hao Chen, Student Member, IEEE, Song Sun is a friction coefficient. The wind turbine model is based on the relation between the upstream wind speed V w + 1 where p is the air density; Rw is the wind turbine radius; cp (A, (3) is the performance

Zambreno, Joseph A.

288

No-slip boundary condition in finite-size dissipative particle dynamics  

Science Conference Proceedings (OSTI)

Dissipative particle dynamics (DPD) is an efficient, particle based mesoscopic numerical scheme to simulate dynamics of complex fluids and micro-flows, with spatio-temporal scales in the range of micrometers and microseconds. While the traditional DPD ... Keywords: Boundary conditions, DPD, Density fluctuations, Impenetrability, No-slip, Tunable slip

S. Kumar Ranjith; B. S. V. Patnaik; Srikanth Vedantam

2013-01-01T23:59:59.000Z

289

DISCRETE AND CONTINUOUS doi:10.3934/dcdss.2010.3.xx DYNAMICAL SYSTEMS SERIES S  

E-Print Network (OSTI)

AND DIMITRIOS MITSOTAKIS where u is the fluid velocity, ± are the fluids densities, µ± are the fluids dynamic is needed for the heavy fluid to acquire the kinetic energy and to enter into the propagation r generation by dynamic displacement of sea bed due to dip-slip faulting. Mathematics and Computers

Paris-Sud XI, Université de

290

Relation between the High Density Phase and the Very-High Density Phase of Amorphous Solid Water  

E-Print Network (OSTI)

Relation between the High Density Phase and the Very-High Density Phase of Amorphous Solid Water; published 18 March 2005) It has been suggested that high-density amorphous (HDA) ice is a structurally arrested form of high- density liquid (HDL) water, while low-density amorphous ice is a structurally

Sciortino, Francesco

291

Density Functional Theory Approach to Nuclear Fission  

E-Print Network (OSTI)

The Skyrme nuclear energy density functional theory (DFT) is used to model neutron-induced fission in actinides. This paper focuses on the numerical implementation of the theory. In particular, it reports recent advances in DFT code development on leadership class computers, and presents a detailed analysis of the numerical accuracy of DFT solvers for near-scission calculations.

N. Schunck

2012-12-13T23:59:59.000Z

292

Nonlinear spectral density estimation: thresholding the correlogram  

E-Print Network (OSTI)

in a nonlinear way. The rate of convergence of the new estimators is quantified, and practical issues estimation of the spectral density function; examples include astronomy, economics, electrical engineering Einstein (1914); see Brillinger (1993) for a historical perspective. The prevalent spectral estimation

Politis, Dimitris N.

293

Density estimation for spatial data streams  

Science Conference Proceedings (OSTI)

In this paper we study the problem of estimating several types of spatial queries in a streaming environment. We propose a new approach, which we call Local Kernels, for computing density estimators by using local rather than global statistics on the ...

Cecilia M. Procopiuc; Octavian Procopiuc

2005-08-01T23:59:59.000Z

294

Lattice QCD and High Baryon Density State  

SciTech Connect

We report our recent studies on the finite density QCD obtained from lattice QCD simulation with clover-improved Wilson fermions of two flavor and RG-improved gauge action. We approach the subject from two paths, i.e., the imaginary and chemical potentials.

Nagata, Keitaro [Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan); Research Institute for Information Science and Education, Hiroshima University, Higashi-Hiroshima 739-8527 (Japan); Nakamura, Atsushi; Motoki, Shinji [Research Institute for Information Science and Education, Hiroshima University, Higashi-Hiroshima 739-8527 (Japan); Nakagawa, Yoshiyuki [Graduate School of Science and Technology, Niigata University, Niigata 950-2181 (Japan); Saito, Takuya [Integrated Information Center, Kochi University, Kochi, 780-8520 (Japan)

2011-10-21T23:59:59.000Z

295

Interferometer for the measurement of plasma density  

SciTech Connect

An interferometer which combines the advantages of a coupled cavity interferometer requiring alignment of only one light beam, and a quadrature interferometer which has the ability to track multi-fringe phase excursions unambiguously. The device utilizes a Bragg cell for generating a signal which is electronically analyzed to unambiguously determine phase modulation which is proportional to the path integral of the plasma density.

Jacobson, Abram R. (Los Alamos, NM)

1980-01-01T23:59:59.000Z

296

Bayesian Generalized Probability Calculus for Density Matrices  

E-Print Network (OSTI)

One of the main concepts in quantum physics is a density matrix, which is a symmetric positive definite matrix of trace one. Finite probability distributions can be seen as a special case when the density matrix is restricted to be diagonal. We develop a probability calculus based on these more general distributions that includes definitions of joints, conditionals and formulas that relate these, including analogs of the Theorem of Total Probability and various Bayes rules for the calculation of posterior density matrices. The resulting calculus parallels the familiar "conventional" probability calculus and always retains the latter as a special case when all matrices are diagonal. We motivate both the conventional and the generalized Bayes rule with a minimum relative entropy principle, where the Kullbach-Leibler version gives the conventional Bayes rule and Umegaki's quantum relative entropy the new Bayes rule for density matrices. Whereas the conventional Bayesian methods maintain uncertainty about which model has the highest data likelihood, the generalization maintains uncertainty about which unit direction has the largest variance. Surprisingly the bounds also generalize: as in the conventional setting we upper bound the negative log likelihood of the data by the negative log likelihood of the MAP estimator.

Manfred K Warmuth; Dima Kuzmin

2009-01-09T23:59:59.000Z

297

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,

298

Probability density function method for variable-density pressure-gradient-driven turbulence and mixing  

SciTech Connect

Probability density function (PDF) methods are extended to variable-density pressure-gradient-driven turbulence. We apply the new method to compute the joint PDF of density and velocity in a non-premixed binary mixture of different-density molecularly mixing fluids under gravity. The full time-evolution of the joint PDF is captured in the highly non-equilibrium flow: starting from a quiescent state, transitioning to fully developed turbulence and finally dissipated by molecular diffusion. High-Atwood-number effects (as distinguished from the Boussinesq case) are accounted for: both hydrodynamic turbulence and material mixing are treated at arbitrary density ratios, with the specific volume, mass flux and all their correlations in closed form. An extension of the generalized Langevin model, originally developed for the Lagrangian fluid particle velocity in constant-density shear-driven turbulence, is constructed for variable-density pressure-gradient-driven flows. The persistent small-scale anisotropy, a fundamentally 'non-Kolmogorovian' feature of flows under external acceleration forces, is captured by a tensorial diffusion term based on the external body force. The material mixing model for the fluid density, an active scalar, is developed based on the beta distribution. The beta-PDF is shown to be capable of capturing the mixing asymmetry and that it can accurately represent the density through transition, in fully developed turbulence and in the decay process. The joint model for hydrodynamics and active material mixing yields a time-accurate evolution of the turbulent kinetic energy and Reynolds stress anisotropy without resorting to gradient diffusion hypotheses, and represents the mixing state by the density PDF itself, eliminating the need for dubious mixing measures. Direct numerical simulations of the homogeneous Rayleigh-Taylor instability are used for model validation.

Bakosi, Jozsef [Los Alamos National Laboratory; Ristorcelli, Raymond J [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

299

Vibrated Bulk Density (VBD) of Calcined Petroleum Coke and ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Vibrated bulk density (VBD) is a quantitative measurement used in the aluminum industry to evaluate the density of calcined petroleum coke.

300

High Energy Density Laboratory Plasmas Program | National Nuclear...  

National Nuclear Security Administration (NNSA)

NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog High Energy Density Laboratory Plasmas Program Home > High Energy Density Laboratory Plasmas...

Note: This page contains sample records for the topic "dynamics md density" 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

An Optimization of Electrode Energy and Power Density through...  

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

An Optimization of Electrode Energy and Power Density through of Variations in Inactive Material and Electrode Porosity Title An Optimization of Electrode Energy and Power Density...

302

Molecular dynamics studies of interfacial water at the alumina surface.  

DOE Green Energy (OSTI)

Interfacial water properties at the alumina surface were investigated via all-atom equilibrium molecular dynamics simulations at ambient temperature. Al-terminated and OH-terminated alumina surfaces were considered to assess the structural and dynamic behavior of the first few hydration layers in contact with the substrates. Density profiles suggest water layering up to {approx}10 {angstrom} from the solid substrate. Planar density distribution data indicate that water molecules in the first interfacial layer are organized in well-defined patterns dictated by the atomic terminations of the alumina surface. Interfacial water exhibits preferential orientation and delayed dynamics compared to bulk water. Water exhibits bulk-like behavior at distances greater than {approx}10 {angstrom} from the substrate. The formation of an extended hydrogen bond network within the first few hydration layers illustrates the significance of water?water interactions on the structural properties at the interface.

Argyris, Dr. Dimitrios [University of Oklahoma; Ho, Thomas [ORNL; Cole, David [Ohio State University

2011-01-01T23:59:59.000Z

303

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

304

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 ...

305

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...

306

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

307

Electrochemical Windows of Room-Temperature Ionic Liquids from Molecular Dynamics and Density Functional Theory Calculations  

E-Print Network (OSTI)

We investigated the cathodic and anodic limits of six room-temperature ionic liquids (ILs) formed from a combination of two common cations, 1-butyl-3-methylimidazolium (BMIM) and N,N-propylmethylpyrrolidinium (P13), and ...

Ong, Shyue Ping

308

Linear and Nonlinear Signatures in the Planetary Wave Dynamics of an AGCM: Probability Density Functions  

Science Conference Proceedings (OSTI)

To identify and quantify indications of linear and nonlinear planetary wave behavior and their impact on the distribution of atmospheric states, characteristics of a very long integration of an atmospheric general circulation model (GCM) in a ...

Judith Berner; Grant Branstator

2007-01-01T23:59:59.000Z

309

Physics and Dynamics of Density-Compensated Temperature and Salinity Anomalies. Part I: Theory  

Science Conference Proceedings (OSTI)

Subducted temperature anomalies have been invoked as a possible way for midlatitudes to alter the climate variability of equatorial regions through the so-called thermocline bridge, both in the Pacific and Atlantic Oceans. To have a significant ...

Rémi Tailleux; Alban Lazar; C. J. C. Reason

2005-05-01T23:59:59.000Z

310

Sieve-based confidence intervals and bands for L\\'{e}vy densities  

E-Print Network (OSTI)

The estimation of the L\\'{e}vy density, the infinite-dimensional parameter controlling the jump dynamics of a L\\'{e}vy process, is considered here under a discrete-sampling scheme. In this setting, the jumps are latent variables, the statistical properties of which can be assessed when the frequency and time horizon of observations increase to infinity at suitable rates. Nonparametric estimators for the L\\'{e}vy density based on Grenander's method of sieves was proposed in Figueroa-L\\'{o}pez [IMS Lecture Notes 57 (2009) 117--146]. In this paper, central limit theorems for these sieve estimators, both pointwise and uniform on an interval away from the origin, are obtained, leading to pointwise confidence intervals and bands for the L\\'{e}vy density. In the pointwise case, our estimators converge to the L\\'{e}vy density at a rate that is arbitrarily close to the rate of the minimax risk of estimation on smooth L\\'{e}vy densities. In the case of uniform bands and discrete regular sampling, our results are consis...

Figueroa-López, José E

2011-01-01T23:59:59.000Z

311

Effective pairing interactions with isospin density dependence  

Science Conference Proceedings (OSTI)

We perform Hartree-Fock-Bogoliubov (HFB) calculations for semi-magic calcium, nickel, tin, and lead isotopes and N=20,28,50, and 82 isotones using density-dependent pairing interactions recently derived from a microscopic nucleon-nucleon interaction. These interactions have an isovector component so that the pairing gaps in symmetric and neutron matter are reproduced. Our calculations well account for the experimental data for the neutron number dependence of binding energy, two-neutron separation energy, and odd-even mass staggering of these isotopes. This result suggests that by introducing the isovector term in the pairing interaction, one can construct a global effective pairing interaction that is applicable to nuclei in a wide range of the nuclear chart. It is also shown with the local density approximation that the pairing field deduced from the pairing gaps in infinite matter reproduces qualitatively well the pairing field for finite nuclei obtained with the HFB method.

Margueron, J. [Institut de Physique Nucleaire, IN2P3-CNRS and Universite Paris-Sud, F-91406 Orsay Cedex (France); Center for Mathematical Sciences, University of Aizu, Aizu-Wakamatsu, 965-8580 Fukushima (Japan); Sagawa, H. [Center for Mathematical Sciences, University of Aizu, Aizu-Wakamatsu, 965-8580 Fukushima (Japan); Hagino, K. [Department of Physics, Tohoku University, Sendai, 980-8578 (Japan)

2008-05-15T23:59:59.000Z

312

Kinetics driving high-density chlorine plasmas  

Science Conference Proceedings (OSTI)

A simple fluid model was developed in order to investigate the driving kinetics of neutral and charged species in high-density chlorine plasmas. It was found that the dissociation degree of Cl{sub 2} molecules is directly linked to the power balance of the discharge which controls the electron density. The model was also used to identify those reactions that could be neglected in the particle balance of charged species and those that must be included. Our results further indicate that diffusion losses need to be considered up to a pressure that depends on magnetic-field intensity and reactor aspect ratio. Finally, it is shown that the dominant charged carriers are linked to the dissociation level of Cl{sub 2} molecules.

Stafford, L.; Margot, J.; Vidal, F.; Chaker, M.; Giroux, K.; Poirier, J.-S.; Quintal-Leonard, A.; Saussac, J. [Department de physique, Universite de Montreal, Montreal, Quebec (Canada); INRS-Energie, Materiaux et Telecommunications, Varennes, Quebec (Canada); Department de physique, Universite de Montreal, Montreal, Quebec (Canada)

2005-09-15T23:59:59.000Z

313

Turbulent Density Spectrum in Solar Wind Plasma  

E-Print Network (OSTI)

The density fluctuation spectrum in the solar wind reveals a Kolmogorov-like scaling with a spectral slope of -5/3 in wavenumber space. The energy transfer process in the magnetized solar wind, characterized typically by MHD turbulence, over extended length-scales remains an unresolved paradox of modern turbulence theories, raising the question of how a compressible magnetofluid exhibits a turbulent spectrum that is characteristic of an incompressible hydrodynamic fluid. To address these questions, we have undertaken three-dimensional time dependent numerical simulations of a compressible magnetohydrodynamic fluid describing super-Alfv\\'enic, supersonic and strongly magnetized plasma fluid. It is shown that a Kolmogorov-like density spectrum can develop by plasma motions that are dominated by Alfv\\'enic cascades whereas compressive modes are dissipated.

Shaikh, Dastgeer

2009-01-01T23:59:59.000Z

314

Density Spectrum in the Solar Wind Plasma  

E-Print Network (OSTI)

The density fluctuation spectrum in the solar wind reveals a Kolmogorov-like scaling with a spectral slope of -5/3 in wavenumber space. The energy transfer process in the magnetized solar wind, characterized typically by MHD turbulence, over extended length-scales remains an unresolved paradox of modern turbulence theories, raising the question of how a compressible magnetofluid exhibits a turbulent spectrum that is characteristic of an incompressible hydrodynamic fluid. To address these questions, we have undertaken three-dimensional time dependent numerical simulations of a compressible magnetohydrodynamic fluid describing super-Alfv\\'enic, supersonic and strongly magnetized plasma fluid. It is shown that a Kolmogorov-like density spectrum can develop by plasma motions that are dominated by Alfv\\'enic cascades whereas compressive modes are dissipated.

Shaikh, Dastgeer

2009-01-01T23:59:59.000Z

315

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

316

Nuclear fission in covariant density functional theory  

E-Print Network (OSTI)

The current status of the application of covariant density functional theory to microscopic description of nuclear fission with main emphasis on superheavy nuclei (SHN) is reviewed. The softness of SHN in the triaxial plane leads to an emergence of several competing fission pathes in the region of the inner fission barrier in some of these nuclei. The outer fission barriers of SHN are considerably affected both by triaxiality and octupole deformation.

A. V. Afanasjev; H. Abusara; P. Ring

2013-09-12T23:59:59.000Z

317

Lipoprotein subclass analysis by immunospecific density  

E-Print Network (OSTI)

Apolipoprotein C-1 (apo C-1) enriched HDL has been described as an atherogenic form of HDL associated with an increased risk for cardiovascular disease (CVD). The objective of the present study was to develop a rapid method for the separation, purification, and characterization of Apo C-1 from serum. We isolated and characterize HDL subclasses from individuals with and without angiographically-proven CVD who have elevated and normal-to-low HDL-C levels. Ultracentrifugation was linked with immunoaffinity separations for the specific separation of Apo C-1 enriched HDL from other lipoproteins. A 50 ?L sample of serum is diluted in TRIS HCl buffer (pH 7.5) and incubated with CNBr-activated Sepharose (Amersham) containing antibodies to apo C-1 (Academy Bio-medical Company). The apo C-1-depleted serum is removed by centrifugation and all apo C-1-containing lipoproteins are released from the Sepharose beads at pH 2. The apo C-1-depleted sample and the apo C-1-containing sample were ultracentrifuged to obtain a lipoprotein density profile in the absence and presence of apo C-1. Density Lipoprotein Profiling (DLP) gives relevant information of lipoproteins, such as density and subclass characterization, and is a novel approach to purify apo C-1-enriched HDL. An additional advantage of this approach is that lipoprotein-a (Lp(a)), which is often an interfering component in the HDL density region, is eliminated. Results show feasibility that these methods could be used in a clinical setting, was achieved. This measurement may yield a precise and quantitative profile of the distribution of apo C-1 for all lipoprotein particles including HDL.

Lester, Sandy Marie

2008-12-01T23:59:59.000Z

318

Princeton Plasma Physics Lab - Particle beam dynamics  

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

particle-beam-dynamics The study of particle-beam-dynamics The study of the physics of charged particle beams and the accelerators that produce them. This cross-disciplinary area intersects with fields such as plasma physics, high-energy density science, and ultra-fast lasers. en Premiere issue of "Quest" magazine details PPPL's strides toward fusion energy and advances in plasma science http://www.pppl.gov/news/2013/09/premiere-issue-quest-magazine-details-pppls-strides-toward-fusion-energy-and-advances-0

319

The string of variable density: Further results  

Science Conference Proceedings (OSTI)

We analyze the problem of calculating the solutions and the spectrum of a string with arbitrary density and fixed ends. We build a perturbative scheme which uses a basis of WKB-type functions and obtain explicit expressions for the eigenvalues and eigenfunctions of the string. Using this approach we show that it is possible to derive the asymptotic (high energy) behavior of the string, obtaining explicit expressions for the first three coefficients (the first two can also be obtained with the WKB method). Finally, using an iterative approach we also obtain analytical expressions for the low energy behavior of the eigenvalues and eigenfunctions of a string with rapidly oscillating density, recovering (in a simpler way) results in the literature. - Highlights: > We devise a perturbative approach to finding the modes of a string with arbitrary density. > We obtain explicitly the first three coefficients of the asymptotic high energy expansion. > We apply our findings to a series of examples, obtaining both analytical and numerical results.

Amore, Paolo, E-mail: paolo.amore@gmail.com

2011-09-15T23:59:59.000Z

320

ON THE LOCAL DARK MATTER DENSITY  

SciTech Connect

An analysis of the kinematics of 412 stars at 1-4 kpc from the Galactic midplane by Moni Bidin et al. has claimed to derive a local density of dark matter that is an order of magnitude below standard expectations. We show that this result is incorrect and that it arises from the assumption that the mean azimuthal velocity of the stellar tracers is independent of Galactocentric radius at all heights. We substitute the assumption, supported by data, that the circular speed is independent of radius in the midplane. We demonstrate that the assumption of constant mean azimuthal velocity is implausible by showing that it requires the circular velocity to drop more steeply than allowed by any plausible mass model, with or without dark matter, at large heights above the midplane. Using the approximation that the circular-velocity curve is flat in the midplane, we find that the data imply a local dark matter density of 0.008 {+-} 0.003 M{sub Sun} pc{sup -3} = 0.3 {+-} 0.1 GeV cm{sup -3}, fully consistent with standard estimates of this quantity. This is the most robust direct measurement of the local dark matter density to date.

Bovy, Jo; Tremaine, Scott [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

2012-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

DYNAMICAL MODEL OF AN EXPANDING SHELL  

Science Conference Proceedings (OSTI)

Expanding blast waves are ubiquitous in many astronomical sources, such as supernova remnants, X-ray emitting binaries, and gamma-ray bursts. I consider here the dynamics of such an expanding blast wave, both in the adiabatic and the radiative regimes. As the blast wave collects material from its surroundings, it decelerates. A full description of the temporal evolution of the blast wave requires consideration of both the energy density and the pressure of the shocked material. The obtained equation is different from earlier works in which only the energy was considered. The solution converges to the familiar results in both the ultrarelativistic and the sub-relativistic (Newtonian) regimes.

Pe'er, Asaf [Harvard-Smithsonian Center for Astrophysics, MS-51, 60 Garden Street, Cambridge, MA 02138 (United States)

2012-06-10T23:59:59.000Z

322

High Energy Density Utracapacitors: Low-Cost, High Energy and Power Density, Nanotube-Enhanced Ultracapacitors  

Science Conference Proceedings (OSTI)

Broad Funding Opportunity Announcement Project: FastCAP is improving the performance of an ultracapacitor—a battery-like electronic device that can complement, and possibly even replace, an HEV or EV battery pack. Ultracapacitors have many advantages over conventional batteries, including long lifespans (over 1 million cycles, as compared to 10,000 for conventional batteries) and better durability. Ultracapacitors also charge more quickly than conventional batteries, and they release energy more quickly. However, ultracapacitors have fallen short of batteries in one key metric: energy density—high energy density means more energy storage. FastCAP is redesigning the ultracapacitor’s internal structure to increase its energy density. Ultracapacitors traditionally use electrodes made of irregularly shaped, porous carbon. FastCAP’s ultracapacitors are made of tiny, aligned carbon nanotubes. The nanotubes provide a regular path for ions moving in and out of the ultracapacitor’s electrode, increasing the overall efficiency and energy density of the device.

None

2010-04-01T23:59:59.000Z

323

Application of optimal prediction to molecular dynamics  

SciTech Connect

Optimal prediction is a general system reduction technique for large sets of differential equations. In this method, which was devised by Chorin, Hald, Kast, Kupferman, and Levy, a projection operator formalism is used to construct a smaller system of equations governing the dynamics of a subset of the original degrees of freedom. This reduced system consists of an effective Hamiltonian dynamics, augmented by an integral memory term and a random noise term. Molecular dynamics is a method for simulating large systems of interacting fluid particles. In this thesis, I construct a formalism for applying optimal prediction to molecular dynamics, producing reduced systems from which the properties of the original system can be recovered. These reduced systems require significantly less computational time than the original system. I initially consider first-order optimal prediction, in which the memory and noise terms are neglected. I construct a pair approximation to the renormalized potential, and ignore three-particle and higher interactions. This produces a reduced system that correctly reproduces static properties of the original system, such as energy and pressure, at low-to-moderate densities. However, it fails to capture dynamical quantities, such as autocorrelation functions. I next derive a short-memory approximation, in which the memory term is represented as a linear frictional force with configuration-dependent coefficients. This allows the use of a Fokker-Planck equation to show that, in this regime, the noise is {delta}-correlated in time. This linear friction model reproduces not only the static properties of the original system, but also the autocorrelation functions of dynamical variables.

Barber IV, John Letherman

2004-12-01T23:59:59.000Z

324

PROCESS FOR IMPROVING THE ENERGY DENSITY OF FEEDSTOCKS USING ...  

PROCESS FOR IMPROVING THE ENERGY DENSITY OF FEEDSTOCKS USING FORMATE SALTS United States Patent Application

325

On the density of a graph and its blowup  

Science Conference Proceedings (OSTI)

It is well known that, of all graphs with edge-density p, the random graph G(n,p) contains the smallest density of copies of K"t","t, the complete bipartite graph of size 2t. Since K"t","t is a t-blowup of an edge, the following intriguing open question ... Keywords: Blowup, Graph density, Triangle density

Asaf Shapira; Raphael Yuster

2010-11-01T23:59:59.000Z

326

Dynamical instabilities of warm npe matter: {delta} meson effects  

Science Conference Proceedings (OSTI)

The effects of {delta} mesons on the dynamical instabilities of cold and warm nuclear and stellar matter at subsaturation densities are studied in the framework of relativistic mean-field hadron models (NL3, NL{rho}, and NL{rho}{delta}) with the inclusion of the electromagnetic field. The distillation effect and the spinodals for all the models considered are discussed. The crust-core transition density and pressure are obtained as a function of temperature for {beta}-equilibrium matter with and without neutrino trapping. An estimation of the size of the clusters formed in the nonhomogeneous phase and the corresponding growth rates are made. It is shown that cluster sizes increase with temperature. The effects of the {delta} meson on the instability region are larger for low temperatures, very asymmetric matter, and densities close to the spinodal surface. It increases the distillation effect above {approx}0.4{rho}{sub 0} and has the opposite effect below that density.

Pais, Helena; Santos, Alexandre; Providencia, Constanca [Centro de Fisica Computacional, Department of Physics, University of Coimbra, 3004-516 Coimbra (Portugal)

2009-10-15T23:59:59.000Z

327

A Model of the Near-Surface Circulation of the Santa Barbara Channel: Comparison with Observations and Dynamical Interpretations  

Science Conference Proceedings (OSTI)

Previous studies indicate the importance of wind, wind curl, and density differences in driving the near-surface circulation in the Santa Barbara Channel (SBC). Here model sensitivity experiments and dynamical analyses of the near-surface ...

Lie-Yauw Oey; Clinton Winant; Ed Dever; Walter R. Johnson; Dong-Ping Wang

2004-01-01T23:59:59.000Z

328

Quantum Dynamical Behaviour in Complex Systems - A Semiclassical Approach  

SciTech Connect

One of the biggest challenges in Chemical Dynamics is describing the behavior of complex systems accurately. Classical MD simulations have evolved to a point where calculations involving thousands of atoms are routinely carried out. Capturing coherence, tunneling and other such quantum effects for these systems, however, has proven considerably harder. Semiclassical methods such as the Initial Value Representation (SC-IVR) provide a practical way to include quantum effects while still utilizing only classical trajectory information. For smaller systems, this method has been proven to be most effective, encouraging the hope that it can be extended to deal with a large number of degrees of freedom. Several variations upon the original idea of the SCIVR have been developed to help make these larger calculations more tractable; these range from the simplest, classical limit form, the Linearized IVR (LSC-IVR) to the quantum limit form, the Exact Forward-Backward version (EFB-IVR). In this thesis a method to tune between these limits is described which allows us to choose exactly which degrees of freedom we wish to treat in a more quantum mechanical fashion and to what extent. This formulation is called the Tuning IVR (TIVR). We further describe methodology being developed to evaluate the prefactor term that appears in the IVR formalism. The regular prefactor is composed of the Monodromy matrices (jacobians of the transformation from initial to finial coordinates and momenta) which are time evolved using the Hessian. Standard MD simulations require the potential surfaces and their gradients, but very rarely is there any information on the second derivative. We would like to be able to carry out the SC-IVR calculation without this information too. With this in mind a finite difference scheme to obtain the Hessian on-the-fly is proposed. Wealso apply the IVR formalism to a few problems of current interest. A method to obtain energy eigenvalues accurately for complex systems is described. We proposed the use of a semiclassical correction term to a preliminary quantum calculation using, for instance, a variational approach. This allows us to increase the accuracy significantly. Modeling Nonadiabatic dynamics has always been a challenge to classical simulations because the multi-state nature of the dynamics cannot be described accurately by the time evolution on a single average surface, as is the classical approach. We show that using the Meyer-Miller-Stock-Thoss (MMST) representation of the exact vibronic Hamiltonian in combination with the IVR allows us to accurately describe dynamics where the non Born-Oppenheimer regime. One final problem that we address is that of extending this method to the long time regime. We propose the use of a time independent sampling function in the Monte Carlo integration over the phase space of initial trajectory conditions. This allows us to better choose the regions of importance at the various points in time; by using more trajectories in the important regions, we show that the integration can be converged much easier. An algorithm based loosely on the methods of Diffusion Monte Carlo is developed that allows us to carry out this time dependent sampling in a most efficient manner.

Gliebe, Cheryn E; Ananth, Nandini

2008-05-22T23:59:59.000Z

329

Non-Gaussianity of the density distribution in accelerating universes  

E-Print Network (OSTI)

According to recent observations, the existence of the dark energy has been considered. Even though we have obtained the constraint of the equation of the state for the dark energy ($p = w \\rho$) as $-1 \\ge w \\ge -0.78$ by combining WMAP data with other astronomical data, in order to pin down $w$, it is necessary to present other independent observational tools. For this purpose, we consider the $w$ dependence of the non-Gaussianity of the density distribution generated by the nonlinear dynamics. In order to subtract the non-Gaussianity, we follow the semi-analytic approach based on the Lagrangian linear perturbation theory which provide accurate value for the quasi-nonlinear region. From our results, the difference of the non-Gaussianity between $w = -1$ and $w= -0.5$ is about 2% while that between $w = -1$ and $w= -0.8$ is about $0.3 %$. For the highly non-linear region, we estimate the difference by combining with this perturbative approach and N-body simulation executed for our previous paper. From this, ...

Tatekawa, T; Tatekawa, Takayuki; Mizuno, Shuntaro

2006-01-01T23:59:59.000Z

330

Nanotechnology in Thoracic Surgery Morgan D. Schulz, MD, Onkar Khullar, MD, John V. Frangioni, MD, PhD,  

E-Print Network (OSTI)

of the lung and the preva- lence of occult micrometastatic disease within thoracic nodes which may appear be due to an increased detection of nodal disease or increased re- moval of nodes harboring occult foci

331

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...

332

HIGH-DENSITY MOLECULAR GAS PROPERTIES OF THE STARBURST GALAXY NGC 1614 REVEALED WITH ALMA  

Science Conference Proceedings (OSTI)

We present the results of HCN/HCO{sup +}/HNC J = 4-3 transition line observations of the nearby starburst galaxy NGC 1614, obtained with ALMA Cycle 0. We find that high density molecular gas traced with these lines shows a velocity structure such that the northern (southern) side of the nucleus is redshifted (blueshifted) with respect to the nuclear velocity of this galaxy. The redshifted and blueshifted emission peaks are offset by {approx}0.''6 at the northern and southern sides of the nucleus, respectively. At these offset positions, observations at infrared >3 {mu}m indicate the presence of active dusty starbursts, supporting the picture that high-density molecular gas is the site of active starbursts. The enclosed dynamical mass within the central {approx}2'' in radius, derived from the dynamics of the high-density molecular gas, is {approx}10{sup 9} M{sub Sun }, which is similar to previous estimates. Finally, the HCN emission is weaker than HCO{sup +} but stronger than HNC for J = 4-3 for all starburst regions of NGC 1614, as seen for J = 1-0 transition lines in starburst-dominated galaxies.

Imanishi, Masatoshi [Subaru Telescope, 650 North A'ohoku Place, Hilo, HI 96720 (United States); Nakanishi, Kouichiro, E-mail: masa.imanishi@nao.ac.jp [Joint ALMA Observatory, Alonso de Cordova 3107, Vitacura 763-0355, Santiago (Chile)

2013-09-15T23:59:59.000Z

333

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.

334

Symmetry energy in nuclear density functional theory  

E-Print Network (OSTI)

The nuclear symmetry energy represents a response to the neutron-proton asymmetry. In this survey we discuss various aspects of symmetry energy in the framework of nuclear density functional theory, considering both non-relativistic and relativistic self-consistent mean-field realizations side-by-side. Key observables pertaining to bulk nucleonic matter and finite nuclei are reviewed. Constraints on the symmetry energy and correlations between observables and symmetry-energy parameters, using statistical covariance analysis, are investigated. Perspectives for future work are outlined in the context of ongoing experimental efforts.

W. Nazarewicz; P. -G. Reinhard; W. Satula; D. Vretenar

2013-07-22T23:59:59.000Z

335

Symmetry energy in nuclear density functional theory  

E-Print Network (OSTI)

The nuclear symmetry energy represents a response to the neutron-proton asymmetry. In this survey we discuss various aspects of symmetry energy in the framework of nuclear density functional theory, considering both non-relativistic and relativistic self-consistent mean-field realizations side-by-side. Key observables pertaining to bulk nucleonic matter and finite nuclei are reviewed. Constraints on the symmetry energy and correlations between observables and symmetry-energy parameters, using statistical covariance analysis, are investigated. Perspectives for future work are outlined in the context of ongoing experimental efforts.

Nazarewicz, W; Satula, W; Vretenar, D

2013-01-01T23:59:59.000Z

336

Local Hotels/Motels - Gaithersburg, MD  

Science Conference Proceedings (OSTI)

... relationship with NIST. We provide this information as a convenience to NIST visitors and conference attendees. NIST does ...

2013-07-25T23:59:59.000Z

337

Fissile Material Disposition (MD) - Nuclear Engineering Division...  

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

a legacy of surplus fissile materials (primarily weapons-grade plutonium and highly enriched uranium) in the United States and the former Soviet Union. These materials pose a...

338

Community Academic Profile Jon D. Fuller, MD  

E-Print Network (OSTI)

, Gerontology, & Metabolism ACTIVITIES 2006 Member, VHA Capacity Management Advisory Council, VA HQ. 2005 Member, VHA Clinical Advisory Council to Chief Business Office, VA HQ. 2005 VA representative to the White Forum Steering Committee Member, "Standardizing Home Health Care Performance Measures" 2004 Organizer

Ford, James

339

Student Directory yea Larry S. Tobacman, MD  

E-Print Network (OSTI)

Genetics St Louis, 2007 Andrew Czysz (2007) aczysz2@uic.edu th Year PhD logy, U. Florida, 2007 Durst (2012

Alford, Simon

340

Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density  

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

1: February 7, 1: February 7, 2011 Population Density to someone by E-mail Share Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density on Facebook Tweet about Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density on Twitter Bookmark Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density on Google Bookmark Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density on Delicious Rank Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density on Digg Find More places to share Vehicle Technologies Office: Fact #661: February 7, 2011 Population Density on AddThis.com... Fact #661: February 7, 2011 Population Density The density of the population in the U.S., measured as the number of people

Note: This page contains sample records for the topic "dynamics md density" 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

Cirrus Outflow Dynamics  

Science Conference Proceedings (OSTI)

Cirrus outflow from deep convection are analyzed as dynamically and thermodynamically active systems. The initial outflow is considered as an analog to wake collapse, in which a neutrally buoyant flow intrusion is flattened and stretched by its ...

Douglas K. Lilly

1988-05-01T23:59:59.000Z

342

WORKSHOP ON NUCLEAR DYNAMICS  

E-Print Network (OSTI)

Complete Events in Medium-Energy Nuclear Collisions" C-Y.+ corrections. (A) The nuclear potential-energy problem isquantum dynamics in high-energy nuclear collisions. We have

Myers, W.D.

2010-01-01T23:59:59.000Z

343

Optical dynamic circuit services  

Science Conference Proceedings (OSTI)

IP service, leased-line service and POTS service have been the three long-standing communication service offerings of providers. Recently, both commercial and research-andeducation network providers have started offering optical dynamic circuit services. ...

Malathi Veeraraghavan; Mark Karol; George Clapp

2010-11-01T23:59:59.000Z

344

A Molecular Dynamics Simulation  

Science Conference Proceedings (OSTI)

Ab Initio Local Energy and Local Stress Calculations: Applications to Materials ... Computational Fluid Dynamics and Experimental Results for the Horizontal .... Films and Applications to a New Generation of Multifunctional Devices/Systems.

345

A Molecular Dynamics  

Science Conference Proceedings (OSTI)

A Tale of Two States and More: Modeling of New Generation of Lattice Stability from Zero ... Analysis of Nano Fluid Using CFD-A Hybrid Approach for Cooling Purpose ... Molecular Dynamics Simulations of Grain Boundary Free Energy and

346

A Molecular Dynamic Study  

Science Conference Proceedings (OSTI)

A Tale of Two States and More: Modeling of New Generation of Lattice Stability from Zero ... Analysis of Nano Fluid Using CFD-A Hybrid Approach for Cooling Purpose ... Molecular Dynamics Simulations of Grain Boundary Free Energy and

347

Frontal Geostrophic Dynamics  

Science Conference Proceedings (OSTI)

From the primitive equations simplified dynamics are derived that apply to frontal situations in which interface slopes are important. The formalism, which eliminates inertial motions, is not Unlike the derivation of the quasi-geostrophic ...

Benoit Cushman-Roisin

1986-01-01T23:59:59.000Z

348

Dislocation Dynamics in an Anisotropic Stripe Pattern  

E-Print Network (OSTI)

The dynamics of dislocations confined to grain boundaries in a striped system are studied using electroconvection in the nematic liquid crystal N4. In electroconvection, a striped pattern of convection rolls forms for sufficiently high driving voltages. We consider the case of a rapid change in the voltage that takes the system from a uniform state to a state consisting of striped domains with two different wavevectors. The domains are separated by domain walls along one axis and a grain boundary of dislocations in the perpendicular direction. The pattern evolves through dislocation motion parallel to the domain walls. We report on features of the dislocation dynamics. The kinetics of the domain motion are quantified using three measures: dislocation density, average domain wall length, and the total domain wall length per area. All three quantities exhibit behavior consistent with power law evolution in time, with the defect density decaying as $t^{-1/3}$, the average domain wall length growing as $t^{1/3}$, and the total domain wall length decaying as $t^{-1/5}$. The two different exponents are indicative of the anisotropic growth of domains in the system.

Carina Kamaga; Fatima Ibrahim; Michael Dennin

2004-04-05T23:59:59.000Z

349

Gas and Dark Matter Spherical Dynamics  

E-Print Network (OSTI)

We investigate the formation of spherical cosmological structures following both dark matter and gas components. We focus on the dynamical aspect of the collapse assuming an adiabatic, $\\gamma = 5/3$, fully ionized primordial plasma. We use for that purpose a fully Lagrangian hydrodynamical code designed to describe highly compressible flows in spherical geometry. We investigate also a "fluid approach" to describe the mean physical quantities of the dark matter flow. We test its validity for a wide range of initial density contrast. We show that an homogeneous isentropic core forms in the gas distribution, surrounded by a self-similar hydrostatic halo, with much higher entropy generated by shock dissipation. We derive analytical expressions for the size, density and temperature of the core, as well as for the surrounding halo. We show that, unless very efficient heating processes occur in the intergalactic medium, we are unable to reproduce within adiabatic models the typical core sizes in X-ray clusters. We also show that, for dynamical reasons only, the gas distribution is naturally antibiased relative to the total mass distribution, without invoking any reheating processes. This could explain why the gas fraction increases with radius in very large X-ray clusters. As a preparation for the next study devoted to the thermodynamical aspect of the collapse, we investigate the initial entropy level required to solve the core problem in X-ray clusters.

Jean-Pierre CHIEZE; Romain Teyssier; Jean-Michel Alimi

1997-04-03T23:59:59.000Z

350

Shock waves in a Z-pinch and the formation of high energy density plasma  

Science Conference Proceedings (OSTI)

A Z-pinch liner, imploding onto a target plasma, evolves in a step-wise manner, producing a stable, magneto-inertial, high-energy-density plasma compression. The typical configuration is a cylindrical, high-atomic-number liner imploding onto a low-atomic-number target. The parameters for a terawatt-class machine (e.g., Zebra at the University of Nevada, Reno, Nevada Terawatt Facility) have been simulated. The 2-1/2 D MHD code, MACH2, was used to study this configuration. The requirements are for an initial radius of a few mm for stable implosion; the material densities properly distributed, so that the target is effectively heated initially by shock heating and finally by adiabatic compression; and the liner's thickness adjusted to promote radial current transport and subsequent current amplification in the target. Since the shock velocity is smaller in the liner, than in the target, a stable-shock forms at the interface, allowing the central load to accelerate magnetically and inertially, producing a magneto-inertial implosion and high-energy density plasma. Comparing the implosion dynamics of a low-Z target with those of a high-Z target demonstrates the role of shock waves in terms of compression and heating. In the case of a high-Z target, the shock wave does not play a significant heating role. The shock waves carry current and transport the magnetic field, producing a high density on-axis, at relatively low temperature. Whereas, in the case of a low-Z target, the fast moving shock wave preheats the target during the initial implosion phase, and the later adiabatic compression further heats the target to very high energy density. As a result, the compression ratio required for heating the low-Z plasma to very high energy densities is greatly reduced.

Rahman, H. U. [Magneto-Inertial Fusion Technologies Inc. (MIFTI), Irvine, California 92612 (United States) and Department of Physics, University of California Irvine, Irvine, California 92697 (United States); Wessel, F. J. [Department of Physics, University of California Irvine, Irvine California 92697 (United States); Ney, P. [Mount San Jacinto College, Menifee, California 92584 (United States); Presura, R. [University of Nevada, Reno, 1664 N. Virginia St., Reno, Nevada 89557-0208 (United States); Ellahi, Rahmat [Department of Mathematics and Statistics, FBAS, IIU, Islamabad (Pakistan) and Department of Mechanical Engineering, University of California Riverside, Riverside, California 92521 (United States); Shukla, P. K. [Department of Mechanical and Aerospace Engineering and Center for Energy Research, University of California San Diego, La Jolla, California 92093 (United States)

2012-12-15T23:59:59.000Z

351

$^{64}$Ni+$^{64}$Ni fusion reaction calculated with the density-constrained time-dependent Hartree-Fock formalism  

E-Print Network (OSTI)

We study fusion reactions of the $^{64}$Ni+$^{64}$Ni system using the density-constrained time-dependent Hartree-Fock (TDHF) formalism. In this formalism the fusion barriers are directly obtained from TDHF dynamics. In addition, we incorporate the entrance channel alignments of the slightly deformed (oblate) $^{64}$Ni nuclei due to dynamical Coulomb excitation. We show that alignment leads to a fusion barrier distribution and alters the naive picture for defining which energies are actually sub-barrier. We also show that core polarization effects could play a significant role in fusion cross section calculations.

A. S. Umar; V. E. Oberacker

2007-09-25T23:59:59.000Z

352

IMPACT OF A REALISTIC DENSITY STRATIFICATION ON A SIMPLE SOLAR DYNAMO CALCULATION  

SciTech Connect

In our Sun, the magnetic cycle is driven by the dynamo action occurring inside the convection zone, beneath the surface. Rotation couples with plasma turbulent motions to produce organized magnetic fields that erupt at the surface and undergo relatively regular cycles of polarity reversal. Among others, the axisymmetric dynamo models have been proved to be a quite useful tool to understand the dynamical processes responsible for the evolution of the solar magnetic cycle and the formation of the sunspots. Here, we discuss the role played by the radial density stratification on the critical layers of the Sun on the solar dynamo. The current view is that a polytropic description of the density stratification from beneath the tachocline region up to the Sun's surface is sufficient for the current precision of axisymmetric dynamo models. In this work, by using an up-to-date density profile obtained from a standard solar model, which is itself consistent with helioseismic data, we show that the detailed peculiarities of the density in critical regions of the Sun's interior, such as the tachocline, the base of the convection zone, the layers of partial ionization of hydrogen and helium, and the super-adiabatic layer, play a non-negligible role on the evolution of the solar magnetic cycle. Furthermore, we found that the chemical composition of the solar model plays a minor role in the formation and evolution of the solar magnetic cycle.

Cardoso, Elisa; Lopes, Ilidio, E-mail: ilidio.lopes@ist.utl.pt [Centro Multidisciplinar de Astrofisica, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal)

2012-09-20T23:59:59.000Z

353

Implementing Molecular Dynamics on Hybrid High Performance Computers - Three-Body Potentials  

SciTech Connect

The use of coprocessors or accelerators such as graphics processing units (GPUs) has become popular in scientific computing applications due to their low cost, impressive floating-point capabilities, high memory bandwidth, and low electrical power re- quirements. Hybrid high-performance computers, defined as machines with nodes containing more than one type of floating-point processor (e.g. CPU and GPU), are now becoming more prevalent due to these advantages. Although there has been extensive research into methods to efficiently use accelerators to improve the performance of molecular dynamics (MD) employing pairwise potential energy models, little is reported in the literature for models that include many-body effects. 3-body terms are required for many popular potentials such as MEAM, Tersoff, REBO, AIREBO, Stillinger-Weber, Bond-Order Potentials, and others. Because the per-atom simulation times are much higher for models incorporating 3-body terms, there is a clear need for efficient algo- rithms usable on hybrid high performance computers. Here, we report a shared-memory force-decomposition for 3-body potentials that avoids memory conflicts to allow for a deterministic code with substantial performance improvements on hybrid machines. We describe modifications necessary for use in distributed memory MD codes and show results for the simulation of water with Stillinger-Weber on the hybrid Titan supercomputer. We compare performance of the 3-body model to the SPC/E water model when using accelerators. Finally, we demonstrate that our approach can attain a speedup of 5.1 with acceleration on Titan for production simulations to study water droplet freezing on a surface.

Brown, W Michael [ORNL] [ORNL; Yamada, Masako [GE Global Research] [GE Global Research

2013-01-01T23:59:59.000Z

354

Dynamic manipulability of multifingered grasping  

Science Conference Proceedings (OSTI)

In this paper, we extend the concept of dynamic manipulability to evaluate the dynamic property of multifingered grasping systems consisting of amultifingered hand and a grasped object, and propose a measure of dynamic manipulability of multifingered ... Keywords: dynamic manipulability, grasping, internal force, multifingered hand, omnidirectionality

Yasuyoshi Yokokohji; Jose San Martin; Masaki Fujiwara

2009-08-01T23:59:59.000Z

355

Ohmically heated high-density Z pinch  

SciTech Connect

The gross properties of a high-density (n approximately equal to 10$sup 27$ m$sup -3$), small-radius, (r = 10$sup -4$ m) gas-imbedded Z pinch have been examined considering only classical processes. The rate equation using only ohmic heating along with bremsstrahlung and radial heat transport shows that ohmic heating will rapidly take the pinch to thermonuclear temperatures for currents, I, greater than 1 MA. The radial heat loss for the pinch is very small for I greater than 1.5 MA. This suggests that the pinch could tolerate being driven to a nearby wall by an m = 1 kink. The laser technology for initiation of the small-diameter filament and the high-voltage technology for giving a 30-ns rise to a MA or more are available now. Some reactor considerations have been included. (auth)

Hammel, J.E.

1976-01-01T23:59:59.000Z

356

Competition between superconductivity and spin density wave  

E-Print Network (OSTI)

The Hubbard model has been investigated widely by many authors, while this work may be new in two aspects. One, we focus on the possible effects of the positions of the gaps associated with the pairing and the spin density wave. Two, we suggest that the models with different parameters are appropriate for different materials (or a material in different doped regions). This will lead to some new insights into the high temperature superconductors. It is shown that the SDW can appear at some temperature region when the on-site Coulomb interaction is larger, while the SC requires a decreased U at a lower temperature. This can qualitatively explain the relationship between superconducting and pseudogap states of Cu-based superconductors in underdoped and optimally doped regions. The superinsulator is also discussed.

Tian De Cao

2011-01-02T23:59:59.000Z

357

Vacuum Outgassing of High Density Polyethylene  

Science Conference Proceedings (OSTI)

A combination of thermogravimetric analysis (TGA) and temperature programmed decomposition (TPD) was employed to identify the outgassing species, the total amount of outgassing, and the outgassing kinetics of high density polyethylene (HDPE) in a vacuum environment. The isoconversional kinetic analysis was then used to analyze the outgassing kinetics and to predict the long-term outgassing of HDPE in vacuum applications at ambient temperature. H{sub 2}O and C{sub n}H{sub x} with n as high as 9 and x centering around 2n are the major outgassing species from solid HDPE, but the quantities evolved can be significantly reduced by vacuum baking at 368 K for a few hours prior to device assembly.

Dinh, L N; Sze, J; Schildbach, M A; Chinn, S C; Maxwell, R S; Raboin, P; McLean II, W

2008-08-11T23:59:59.000Z

358

BRST technique for the cosmological density matrix  

E-Print Network (OSTI)

The microcanonical density matrix in closed cosmology has a natural definition as a projector on the space of solutions of Wheeler-DeWitt equations, which is motivated by the absence of global non-vanishing charges and energy in spatially closed gravitational systems. Using the BRST/BFV formalism in relativistic phase space of gauge and ghost variables we derive the path integral representation for this projector and the relevant statistical sum. This derivation circumvents the difficulties associated with the open algebra of noncommutative quantum Dirac constraints and the construction/regularization of the physical inner product in the subspace of BRS singlets. This inner product is achieved via the Batalin-Marnelius gauge fixing in the space of BRS-invariant states, which in its turn is shown to be a result of truncation of the BRST/BFV formalism to the "matter" sector of relativistic phase space.

Andrei O. Barvinsky

2013-08-14T23:59:59.000Z

359

High power density supercapacitors using locally aligned carbon nanotube electrodes  

E-Print Network (OSTI)

B E 1999 Electrochemical Supercapacitor ( New York: Kluwer–power density of a supercapacitor is its most remarkablepower density of a supercapacitor is given by P max = V i

Du, C S; Yeh, J; Pan, Ning

2005-01-01T23:59:59.000Z

360

Orthobaric Density: A Thermodynamic Variable for Ocean Circulation Studies  

Science Conference Proceedings (OSTI)

A new density variable, empirically corrected for pressure, is constructed. This is done by first fitting compressibility (or sound speed) computed from global ocean datasets to an empirical function of pressure and in situ density (or specific ...

Roland A. de Szoeke; Scott R. Springer; David M. Oxilia

2000-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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

Innovative fuel designs for high power density pressurized water reactor  

E-Print Network (OSTI)

One of the ways to lower the cost of nuclear energy is to increase the power density of the reactor core. Features of fuel design that enhance the potential for high power density are derived based on characteristics of ...

Feng, Dandong, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

362

Constrained Density-Functional Theory--Configuration Interaction  

E-Print Network (OSTI)

In this thesis, I implemented a method for performing electronic structure calculations, "Constrained Density Functional Theory-- Configuration Interaction" (CDFT-CI), which builds upon the computational strengths of Density ...

Kaduk, Benjamin James

2012-01-01T23:59:59.000Z

363

Design of annular fuel for high power density BWRs  

E-Print Network (OSTI)

Enabling high power density in the core of Boiling Water Reactors (BWRs) is economically profitable for existing or new reactors. In this work, we examine the potential for increasing the power density in BWR plants by ...

Morra, Paolo

2005-01-01T23:59:59.000Z

364

Density of Freshly Fallen Snow in the Central Rocky Mountains  

Science Conference Proceedings (OSTI)

New snow density distributions are presented for six measurement sites in the mountains of Colorado and Wyoming. Densities were computed from daily measurements of new snow depth and water equivalent from snow board cores. All data were measured ...

Arthur Judson; Nolan Doesken

2000-07-01T23:59:59.000Z

365

Controlling Defect Density in Polymer-Fullerene Bulk Heterojunction ...  

Science Conference Proceedings (OSTI)

Controlling Defect Density in Polymer-Fullerene Bulk Heterojunction Solar Cells by Optimizing ... Engineering Carbon Nanomaterials for Energy Application.

366

Density without Disruption [EDRA / Places Awards, 2004 -- Awards Commentary  

E-Print Network (OSTI)

Density without Disruption Awards Commentary country today,CCS Architecture for a planning award. Such work stands as a

Gratz, Roberta Brandes

2004-01-01T23:59:59.000Z

367

Inexpensive Production of High Density Thin Ceramic Films ...  

For Industry; For Researchers; Success Stories; About Us; Available Technologies. Browse By Category Advanced Materials; ... density of the ceramic ...

368

Fatigue Weak-Link Density and Strength Distribution in High ...  

Science Conference Proceedings (OSTI)

Symposium, Fatigue and Corrosion Damage in Metallic Materials: Fundamentals, Modeling and Prevention. Presentation Title, Fatigue Weak-Link Density and ...

369

Improving Baked Anode Density and Air Permeability Through ...  

Science Conference Proceedings (OSTI)

Presentation Title, Improving Baked Anode Density and Air Permeability Through Process Optimization and Coke Blending. Author(s), Bienvenu Ndjom, ...

370

The Dynamical Discrete Web  

E-Print Network (OSTI)

The dynamical discrete web (DDW), introduced in recent work of Howitt and Warren, is a system of coalescing simple symmetric one-dimensional random walks which evolve in an extra continuous dynamical parameter s. The evolution is by independent updating of the underlying Bernoulli variables indexed by discrete space-time that define the discrete web at any fixed s. In this paper, we study the existence of exceptional (random) values of s where the paths of the web do not behave like usual random walks and the Hausdorff dimension of the set of such exceptional s. Our results are motivated by those about exceptional times for dynamical percolation in high dimension by H\\"aggstrom, Peres and Steif, and in dimension two by Schramm and Steif. The exceptional behavior of the walks in DDW is rather different from the situation for dynamical random walks of Benjamini, H\\"aggstrom, Peres and Steif. In particular, we prove that there are exceptional values of s for which the walk from the origin S^s(n) has limsup S^s(n)/\\sqrt n \\leq K with a nontrivial dependence of the Hausdorff dimension on K. We also discuss how these and other results extend to the dynamical Brownian web, a natural scaling limit of DDW. The scaling limit is the focus of a paper in preparation; it was studied by Howitt and Warren and is related to the Brownian net of Sun and Swart.

L. R. G. Fontes; C. M. Newman; K. Ravishankar; E. Schertzer

2007-04-20T23:59:59.000Z

371

A digital rock density map of New Zealand  

Science Conference Proceedings (OSTI)

Digital geological maps of New Zealand (QMAP) are combined with 9256 samples with rock density measurements from the national rock catalogue PETLAB and supplementary geological sources to generate a first digital density model of New Zealand. This digital ... Keywords: Crust, Database, Density, Geological mapping, Gravimetry, Rock types

Robert Tenzer; Pascal Sirguey; Mark Rattenbury; Julia Nicolson

2011-08-01T23:59:59.000Z

372

High fidelity field simulations using density and pressure based approaches  

Science Conference Proceedings (OSTI)

Density-based and pressure-based approaches in solving the Navier-Stokes equations for computational field simulations for compressible and incompressible flows have been presented. For the density-based flow solver, a generalized grid based framework ... Keywords: CFD, Density-based method, Pressure-based method

Gary C. Cheng; Roy P. Koomullil; Bharat K. Soni

2005-11-01T23:59:59.000Z

373

Density-Enthalpy Phase Diagram 0D Boiler Simulation  

E-Print Network (OSTI)

Density-Enthalpy Phase Diagram 0D Boiler Simulation Finite Element Method Further Research Finite Transitions #12;Density-Enthalpy Phase Diagram 0D Boiler Simulation Finite Element Method Further Research;Density-Enthalpy Phase Diagram 0D Boiler Simulation Finite Element Method Further Research Goal

Vuik, Kees

374

Quantum coherent switch utilizing commensurate nanoelectrode and charge density periodicities  

DOE Patents (OSTI)

A quantum coherent switch having a substrate formed from a density wave (DW) material capable of having a periodic electron density modulation or spin density modulation, a dielectric layer formed onto a surface of the substrate that is orthogonal to an intrinsic wave vector of the DW material; and structure for applying an external spatially periodic electrostatic potential over the dielectric layer.

Harrison, Neil (Santa Fe, NM); Singleton, John (Los Alamos, NM); Migliori, Albert (Santa Fe, NM)

2008-08-05T23:59:59.000Z

375

Local Polarization Dynamics in Ferroelectric Materials  

SciTech Connect

Ferroelectrics and multiferroics have recently emerged as perspective materials for information technology and data storage applications. The combination of extremely narrow domain wall width and the capability to manipulate polarization by electric field opens the pathway towards ultrahigh (>10 TBit/in2) storage densities and small (sub-10 nm) feature sizes. The coupling between polarization and chemical and transport properties enables applications in ferroelectric lithography and electroresistive devices. The progress in these applications, as well as fundamental studies of polarization dynamics and the role of defects and disorder on domain nucleation and wall motion, requires the capability to probe these effects on the nanometer scale. In this review, we summarize recent progress in applications of Piezoresponse Force Microscopy (PFM) for imaging, manipulation, and spectroscopy of ferroelectric switching processes. We briefly introduce the principles and relevant instrumental aspects of PFM, with special emphasis on resolution and information limits. The local imaging studies of domain dynamics, including local switching and relaxation accessed through imaging experiments, and spectroscopic studies of polarization switching, are discussed in detail. Finally, we briefly review the recent progress on photochemical processes on ferroelectric surfaces, the role of surface adsorbates, and imaging and switching in liquids. Beyond classical applications, probing local bias-induced transition dynamics by PFM opens the pathway to studies of the influence of a single defect on electrochemical and solid state processes, thus providing model systems for batteries, fuel cells, and supercapacitor applications.

Kalinin, Sergei V [ORNL; Morozovska, A. N. [National Academy of Science of Ukraine, Kiev, Ukraine; Chen, L. Q. [Pennsylvania State University; Rodriguez, Brian J [ORNL

2010-01-01T23:59:59.000Z

376

Molecular Dynamics Simulation of Solidification in Cu50Zr50 Alloy  

Science Conference Proceedings (OSTI)

Next, MD simulation of melting B2 phase surrounded by liquid was .... Thermochemical Models and Phase Equilibria of Urania Rare Earth Fluorite Phases.

377

Surface Chemical Dynamics  

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

Surface Chemical Dynamics Surface Chemical Dynamics The goal of the Surface Chemical Dynamics Program is to elucidate the underlying physical processes that determine the products (selectivity) and yield (efficiency) of chemical transformations relevant to energy-related chemistry on catalytic and nanostructured surfaces. Achieving this end requires understanding the evolution of the reactant-molecule/surface complex as molecules adsorb, bonds dissociate, surface species diffuse, new bonds form and products desorb. The pathways and time scales of these processes are ultimately determined by a multidimensional potential energy surface that is a function of the geometric and electronic structures of the surface and the reactant, product, intermediate and transition-state molecular and atomic species.

378

MAX Fluid Dynamics facility  

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

MAX Fluid Dynamics facility MAX Fluid Dynamics facility Capabilities Engineering Experimentation Reactor Safety Testing and Analysis Overview Nuclear Reactor Severe Accident Experiments MAX NSTF SNAKE Aerosol Experiments System Components Laser Applications Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr MAX Fluid Dynamics facility Providing high resolution data for development of computational tools that model fluid flow and heat transfer within complex systems such as the core of a nuclear reactor. 1 2 3 4 5 Hot and cold air jets are mixed within a glass tank while laser-based anemometers and a high-speed infrared camera characterize fluid flow and heat transfer behavior. Click on image to view larger size image.

379

Violations of conservation laws in viscous liquid dynamics  

E-Print Network (OSTI)

The laws expressing conservation of momentum and energy apply to any isolated system, but these laws are violated for for highly viscous liquids under laboratory conditions because of the unavoidable interactions with the measuring equipment over the long times needed to study the dynamics. Although particle number conservation applies strictly for any liquid, the solidity of viscous liquids implies that even this conservation law is apparently violated in coarse-grained descriptions of density fluctuations.

Jeppe C. Dyre

2006-03-01T23:59:59.000Z

380

Effect of Current Density and Phosphorus Impurities on the Current ...  

Science Conference Proceedings (OSTI)

Multivariate Statistical Investigation of Carbon Consumption for HSS Reduction Cell · Numerical Investigation of Bubble Dynamics in Aluminium Electrolytic Cells .

Note: This page contains sample records for the topic "dynamics md density" 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

Density matrix, superconductivity and molecular structure  

Science Conference Proceedings (OSTI)

Starting from Yang`s offdiagonal long-range order concept and the macroscopic occupation condition for the second order density matrix as the basis for condensation phenomena the authors develop the notion that the extremal wave function (EWF), which is related to these conditions, leads to superconductivity in monatomic systems. It is proven that the BCS model and the version where it is projected onto a fixed number of particles possesses EWF properties, differs negligibly from the EWF, and conserves offdiagonal long-range order. The condition for the EWF to be energetically favored is the presence of macroscopic degenerate one-electron energy levels in the system, partial occupation of this degenerate region, and also an effective attraction among the electrons. Considerations are advanced indicating that these conditions are satisfied in the high temperature superconducting metal oxide ceramics, due to the presence of macroscopically degenerate diffusion orbitals distributed among the O{sup -} ions in the CuO{sub 2} layers, and with the effective screening of these layers by the metal-like La, Ba, Y, or O layers. 51 refs., 3 figs., 1 tab.

Mestechkin, M.M.; Klimko, G.T.; Vaiman, G.E. [Academy of Science of the Ukrainian SSR, Donetsk (Russian Federation)

1992-01-01T23:59:59.000Z

382

wind power density | OpenEI  

Open Energy Info (EERE)

density density Dataset Summary Description This dataset was developed by the National Renewable Energy Laboratory (NREL) for the U.S. Source National Renewable Energy Lab (NREL) Date Released Unknown Date Updated Unknown Keywords afghanistan dataset GIS Wind Power wind power density Data application/zip icon Wind Power Density at 50-m Above Ground Level GIS Data (zip, 1.4 MiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period License License Other or unspecified, see optional comment below Comment DISCLAIMER NOTICE This GIS data was developed by the National Renewable Energy Laboratory ("NREL"), which is operated by the Alliance for Sustainable Energy, LLC for the U.S. Department of Energy ("DOE"). The user is granted the right, without any fee or cost, to use, copy, modify, alter, enhance and distribute this data for any purpose whatsoever, provided that this entire notice appears in all copies of the data. Further, the user of this data agrees to credit NREL in any publications or software that incorporate or use the data. Access to and use of the GIS data shall further impose the following obligations on the User. The names DOE/NREL may not be used in any advertising or publicity to endorse or promote any product or commercial entity using or incorporating the GIS data unless specific written authorization is obtained from DOE/NREL. The User also understands that DOE/NREL shall not be obligated to provide updates, support, consulting, training or assistance of any kind whatsoever with regard to the use of the GIS data. THE GIS DATA IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DOE/NREL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER, INCLUDING BUT NOT LIMITED TO CLAIMS ASSOCIATED WITH THE LOSS OF DATA OR PROFITS, WHICH MAY RESULT FROM AN ACTION IN CONTRACT, NEGLIGENCE OR OTHER TORTIOUS CLAIM THAT ARISES OUT OF OR IN CONNECTION WITH THE ACCESS OR USE OF THE GIS DATA. The User acknowledges that access to the GIS data is subject to U.S. Export laws and regulations and any use or transfer of the GIS data must be authorized under those regulations. The User shall not use, distribute, transfer, or transmit GIS data or any products incorporating the GIS data except in compliance with U.S. export regulations. If requested by DOE/NREL, the User agrees to sign written assurances and other export-related documentation as may be required to comply with U.S. export regulations. DISCLAIMER NOTICE This GIS data was developed by the National Renewable Energy Laboratory ("NREL"), which is operated by the Alliance for Sustainable Energy, LLC for the U.S. Department of Energy ("DOE"). The user is granted the right, without any fee or cost, to use, copy, modify, alter, enhance and distribute this data for any purpose whatsoever, provided that this entire notice appears in all copies of the data. Further, the user of this data agrees to credit NREL in any publications or software that incorporate or use the data. Access to and use of the GIS data shall further impose the following obligations on the User. The names DOE/NREL may not be used in any advertising or publicity to endorse or promote any product or commercial entity using or incorporating the GIS data unless specific written authorization is obtained from DOE/NREL. The User also understands that DOE/NREL shall not be obligated to provide updates, support, consulting, training or assistance of any kind whatsoever with regard to the use of the GIS data. THE GIS DATA IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DOE/NREL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER, INCLUDING BUT NOT LIMITED TO CLAIMS ASSOCIATED WITH THE LOSS OF DATA OR PROFITS, WHICH MAY RESULT FROM AN ACTION IN CONTRACT, NEGLIGENCE OR OTHER TORTIOUS CLAIM THAT ARISES OUT OF OR IN CONNECTION WITH THE ACCESS OR USE OF THE GIS DATA. The User acknowledges that access to the GIS data is subject to U.S. Export laws and regulations and any use or transfer of the GIS data must be authorized under those regulations. The User shall not use, distribute, transfer, or transmit GIS data or any products incorporating the GIS data except in compliance with U.S. export regulations. If requested by DOE/NREL, the User agrees to sign written assurances and other export-related documentation as may be required to comply with U.S. export regulations.

383

Introduction to Accelerated Molecular Dynamics  

SciTech Connect

Molecular Dynamics is the numerical solution of the equations of motion of a set of atoms, given an interatomic potential V and some boundary and initial conditions. Molecular Dynamics is the largest scale model that gives unbiased dynamics [x(t),p(t)] in full atomistic detail. Molecular Dynamics: is simple; is 'exact' for classical dynamics (with respect to a given V); can be used to compute any (atomistic) thermodynamical or dynamical properties; naturally handles complexity -- the system does the right thing at the right time. The physics derives only from the interatomic potential.

Perez, Danny [Los Alamos National Laboratory

2012-07-10T23:59:59.000Z

384

Introduction to Accelerated Molecular Dynamics  

SciTech Connect

Molecular Dynamics is the numerical solution of the equations of motion of a set of atoms, given an interatomic potential V and some boundary and initial conditions. Molecular Dynamics is the largest scale model that gives unbiased dynamics [x(t),p(t)] in full atomistic detail. Molecular Dynamics: is simple; is 'exact' for classical dynamics (with respect to a given V); can be used to compute any (atomistic) thermodynamical or dynamical properties; naturally handles complexity -- the system does the right thing at the right time. The physics derives only from the interatomic potential.

Perez, Danny [Los Alamos National Laboratory

2012-07-10T23:59:59.000Z

385

Quantitative discrimination between geological materials with variable density contrast by high resolution X-ray computed tomography: An example using amygdule size-distribution in ancient lava flows  

Science Conference Proceedings (OSTI)

The bubble-size distribution in 2.7 billion year old lava flows can be used as a proof of concept illustrating a new set of techniques for measuring volumes of geological materials with variable density contrasts using high-resolution X-ray computed ... Keywords: Amygdules, Bootstrap resampling, Bubble-size distribution, Central limit theorem, Dynamic thresholding, X-ray tomography

Sanjoy M. Som, James W. Hagadorn, Weston A. Thelen, Alan R. Gillespie, David C. Catling, Roger Buick

2013-04-01T23:59:59.000Z

386

An Ocean Dynamical Thermostat  

Science Conference Proceedings (OSTI)

The role of ocean dynamics in the regulation of tropical sea surface temperatures (SSTs) is investigated using the Zebiak-Cane coupled occan-atmosphere model. The model is forced with a uniform heating, or cooling, varying between ±40 W m?2 into ...

Amy C. Clement; Richard Seager; Mark A. Cane; Stephen E. Zebiak

1996-09-01T23:59:59.000Z

387

Neutron Scattering and Dynamics  

Science Conference Proceedings (OSTI)

... "Molecule" H2O (N2)0.8(O2)0.2 Al Cd sigma_s barn 168.3 20.1 1.5 6.5 ... 31 Collective dynamics Animation courtesy of A. Zheludev (ORNL) ...

2009-09-15T23:59:59.000Z

388

Tropical Cyclone Eye Dynamics  

Science Conference Proceedings (OSTI)

A new perspective of the dynamics of a tropical cyclone eye is given in which eye subsidence and the adiabatic warming accompanying it are accounted for directly from the equations of motion. Subsidence is driven by an adverse, axial gradient of ...

R. K. Smith

1980-06-01T23:59:59.000Z

389

Bütschli dynamic droplet system  

Science Conference Proceedings (OSTI)

Dynamical oil-water systems such as droplets display lifelike properties and may lend themselves to chemical programming to perform useful work, specifically with respect to the built environment. We present Bütschli water-in-oil droplets as a model ... Keywords: Otto Bütschli, architecture, droplet, living technology, olive oil, origins of life

Rachel Armstrong; Martin Hanczyc

2013-10-01T23:59:59.000Z

390

BLOWER SYSTEM DYNAMICS  

SciTech Connect

An analysis is presented of the dynamics of a turboblower acting together with its connecting circuit. This is to be distinguished from the aero- thermodynamics involved in the design of the blower itself. The effect on system stability of blower and circuit characteristics is discussed. (auth)

Furgerson, W.T.

1958-04-16T23:59:59.000Z

391

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

392

Gas-cooling by dust during dynamical fragmentation  

E-Print Network (OSTI)

We suggest that the abrupt switch, from hierarchical clustering on scales larger than 0.04 pc, to binary (and occasionally higher multiple) systems on smaller scales, which Larson has deduced from his analysis of the grouping of pre-Main-Sequence stars in Taurus, arises because pre-protostellar gas becomes thermally coupled to dust at sufficiently high densities. The resulting change from gas-cooling by molecular lines at low densities to gas-cooling by dust at high densities enables the matter to radiate much more efficiently, and hence to undergo dynamical fragmentation. We derive the domain where gas-cooling by dust facilitates dynamical fragmentation. Low-mass (i.e. solar mass) clumps - those supported mainly by thermal pressure - can probably access this domain spontaneously, albeit rather quasistatically, provided they exist in a region where external perturbations are few and far between. More massive clumps probably require an impulsive external perturbation, for instance a supersonic collision with another clump, in order for the gas to reach sufficiently high density to couple thermally to the dust. Impulsive external perturbations should promote fragmentation, by generating highly non-line ar substructures which can then be amplified by gravity during the subsequent collapse.

A. P. Whitworth; H. M. J. Boffin; N. Francis

1998-04-30T23:59:59.000Z

393

Flat Central Density Profile and Constant DM Surface Density in Galaxies from Scalar Field Dark Matter  

E-Print Network (OSTI)

The scalar field dark matter (SFDM) model proposes that galaxies form by condensation of a scalar field (SF) very early in the universe forming Bose-Einstein Condensates (BEC) drops, i.e., in this model haloes of galaxies are gigantic drops of SF. Here big structures form like in the LCDM model, by hierarchy, thus all the predictions of the LCDM model at big scales are reproduced by SFDM. This model predicts that all galaxies must be very similar and exist for bigger redshifts than in the LCDM model. In this work we show that BEC dark matter haloes fit high-resolution rotation curves of a sample of thirteen low surface brightness galaxies. We compare our fits to those obtained using a Navarro-Frenk-White and Pseudo-Isothermal (PI) profiles and found a better agreement with the SFDM and PI profiles. The mean value of the logarithmic inner density slopes is -0.27 +/- 0.18. As a second result we find a natural way to define the core radius with the advantage of being model-independent. Using this new definition in the BEC density profile we find that the recent observation of the constant dark matter central surface density can be reproduced. We conclude that in light of the difficulties that the standard model is currently facing the SFDM model can be a worthy alternative to keep exploring further.

Victor H. Robles; Tonatiuh Matos

2012-01-14T23:59:59.000Z

394

Hard Sphere Dynamics for Normal and Granular Fluids  

E-Print Network (OSTI)

A fluid of N smooth, hard spheres is considered as a model for normal (elastic collisions) and granular (inelastic collisions) fluids. The potential energy is discontinuous for hard spheres so the pairwise forces are singular and the usual forms of Newtonian and Hamiltonian mechanics do not apply. Nevertheless, particle trajectories in the N particle phase space are well defined and the generators for these trajectories can be identified. The first part of this presentation is a review of the generators for the dynamics of observables and probability densities. The new results presented in the second part refer to applications of these generators to the Liouville dynamics for granular fluids. A set of eigenvalues and eigenfunctions of the generator for this Liouville dynamics is identified in a special "stationary representation". This provides a class of exact solutions to the Liouville equation that are closely related to hydrodynamics for granular fluids.

James W. Dufty; Aparna Baskaran

2005-03-08T23:59:59.000Z

395

The nuclear energy density functional formalism  

E-Print Network (OSTI)

The present document focuses on the theoretical foundations of the nuclear energy density functional (EDF) method. As such, it does not aim at reviewing the status of the field, at covering all possible ramifications of the approach or at presenting recent achievements and applications. The objective is to provide a modern account of the nuclear EDF formalism that is at variance with traditional presentations that rely, at one point or another, on a {\\it Hamiltonian-based} picture. The latter is not general enough to encompass what the nuclear EDF method represents as of today. Specifically, the traditional Hamiltonian-based picture does not allow one to grasp the difficulties associated with the fact that currently available parametrizations of the energy kernel $E[g',g]$ at play in the method do not derive from a genuine Hamilton operator, would the latter be effective. The method is formulated from the outset through the most general multi-reference, i.e. beyond mean-field, implementation such that the single-reference, i.e. "mean-field", derives as a particular case. As such, a key point of the presentation provided here is to demonstrate that the multi-reference EDF method can indeed be formulated in a {\\it mathematically} meaningful fashion even if $E[g',g]$ does {\\it not} derive from a genuine Hamilton operator. In particular, the restoration of symmetries can be entirely formulated without making {\\it any} reference to a projected state, i.e. within a genuine EDF framework. However, and as is illustrated in the present document, a mathematically meaningful formulation does not guarantee that the formalism is sound from a {\\it physical} standpoint. The price at which the latter can be enforced as well in the future is eventually alluded to.

T. Duguet

2013-09-02T23:59:59.000Z

396

Cloud computing for dynamic systems  

Science Conference Proceedings (OSTI)

Cloud computing is a fast emerging model for enabling dynamic on-demand computing and IT-based services. It promotes dynamic properties and characteristics such as scalability, agility, flexibility, virtualised and distributed on-demand computing. However, ...

Khaled Sabry

2011-11-01T23:59:59.000Z

397

Dynamic Scaling of Manipulator Trajectories  

E-Print Network (OSTI)

A fundamental time-scaling property of manipulator dynamics has been identified that allows modification of movement speed without complete dynamics recalculation. By exploiting this property, it can be determined ...

Hollerbach, John M.

1983-01-01T23:59:59.000Z

398

NETL: Energy System Dynamics Focus Area  

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

Energy System Dynamics Onsite Research Energy System Dynamics Energy System Dynamics (ESD) is a focus area of the National Energy Technology Laboratory's Office of Research and...

399

Shared and Dynamic Libraries on Edison  

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

Shared and Dynamic Libraries Shared and Dynamic Libraries The Edison system can support applications that use dynamic shared libraries (DSL) on the compute nodes. Some...

400

Dynamic Worldwide Solar Energy | Open Energy Information  

Open Energy Info (EERE)

Dynamic Worldwide Solar Energy Jump to: navigation, search Name Dynamic Worldwide Solar Energy Sector Solar Product US-based solar developer and financer. References Dynamic...

Note: This page contains sample records for the topic "dynamics md density" 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.


401

Cell Dynamics and Process Control  

Science Conference Proceedings (OSTI)

ALUMINIUM REDUCTION TECHNOLOGY VII: Cell Dynamics And Process ... WITH RELEVANS TO POINT FEEDING ALUMINIUM CELL: Ove Kobbeltvedt, ...

402

Dynamic Behavior of Materials VI  

Science Conference Proceedings (OSTI)

Capturing Microstructural Features Related to Dynamic Damage Nucleation ... Structural Alumina during Low Velocity Impact Used in Protective Systems.

403

Density Inhomogeneities and Electron Mobility in Supercritical Xenon  

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

Density Inhomogeneities and Electron Mobility in Supercritical Xenon Density Inhomogeneities and Electron Mobility in Supercritical Xenon Richard A. Holroyd, Kengo Itoh, and Masaru Nishikawa J. Chem. Phys. 118, 706-710 (2003) [Find paper at Scitation] Abstract: The low-field mobility of electrons in supercritical Xe has been measured isothermally as a function of density above the critical temperature (289.7 K). At 293 K the mobility varies from a high of 890 cm2/Vs at 9.2 x 1021 atoms/cm3 to a minimum value of 4.6 cm2/Vs at a density of 3.5 x 1021 atoms/cm3, which is just below the critical density. The density dependence of the mobility is reasonably well predicted by the deformation potential model if the adiabatic compressibility is used to characterize the electron-medium interactions. Approximate agreement indicates that

404

The Quantum Energy Density: Improved Efficiency for Quantum Monte Carlo  

E-Print Network (OSTI)

We establish a physically meaningful representation of a quantum energy density for use in Quantum Monte Carlo calculations. The energy density operator, defined in terms of Hamiltonian components and density operators, returns the correct Hamiltonian when integrated over a volume containing a cluster of particles. This property is demonstrated for a helium-neon "gas," showing that atomic energies obtained from the energy density correspond to eigenvalues of isolated systems. The formation energies of defects or interfaces are typically calculated as total energy differences. Using a model of delta-doped silicon (where dopant atoms form a thin plane) we show how interfacial energies can be calculated more efficiently with the energy density, since the region of interest is small. We also demonstrate how the energy density correctly transitions to the bulk limit away from the interface where the correct energy is obtainable from a separate total energy calculation.

Krogel, Jaron T; Kim, Jeongnim; Ceperley, David M

2013-01-01T23:59:59.000Z

405

Interaction between economic dynamical systems  

Science Conference Proceedings (OSTI)

The paper considers economic dynamical systems, the state spaces being the Riemannian manifolds. Between two economic dynamical systems, global feedforward and the feedback interaction is defined and the connection between their linearization and prolongation ... Keywords: economic dynamical system, economic flow, feedback, feedforward, linearization, prolongation by derivation

Constantin Patrascoiu

2009-07-01T23:59:59.000Z

406

Accelerated Molecular Dynamics Methods  

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

Dynamics Methods Dynamics Methods for Infrequent Events Arthur F. Voter Theoretical Division Los Alamos National Laboratory Los Alamos, New Mexico U.S. Department of Energy Theory Focus Session on Hydrogen Storage Materials Crystal City, VA May 18, 2006 Los Alamos Acknowledgments Blas P. Uberuaga (LANL, MST-8) Francesco Montalenti (U. Milano-Bicocca) Graeme Henkelman (U. Texas at Austin) Timothy C. Germann (LANL, X-7) James A. Sprague (NRL) Mads Sorensen (Novo Nordisk A/S, Copenhagen) Sriram Swaminarayan (LANL, MST-8) Steve Stuart (Clemson) David Sholl (Carnegie Mellon) John Hamilton (Sandia) Wolfgang Windl (Ohio State) Roger Smith (U. Loughborough) Robin Grimes (Imperial College) Kurt Sickafus (LANL, MST-8) Jacques Amar (U. Toledo) DOE Office of Basic Energy Sciences Motorola Intel Los Alamos Outline

407

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

408

Social Dynamics of Science  

E-Print Network (OSTI)

The birth and decline of disciplines are critical to science and society. However, no quantitative model to date allows us to validate competing theories of whether the emergence of scientific disciplines drives or follows the formation of social communities of scholars. Here we propose an agent-based model based on a \\emph{social dynamics of science,} in which the evolution of disciplines is guided mainly by the social interactions among scientists. We find that such a social theory can account for a number of stylized facts about the relationships between disciplines, authors, and publications. These results provide strong quantitative support for the key role of social interactions in shaping the dynamics of science. A "science of science" must gauge the role of exogenous events, such as scientific discoveries and technological advances, against this purely social baseline.

Sun, Xiaoling; Milojevi?, Staša; Flammini, Alessandro; Menczer, Filippo

2013-01-01T23:59:59.000Z

409

Nuclear symmetry energy at subnormal densities from measured nuclear masses  

E-Print Network (OSTI)

The symmetry energy coefficients for nuclei with mass number A=20~250 are extracted from more than 2000 measured nuclear masses. With the semi-empirical connection between the symmetry energy coefficients of finite nuclei and the nuclear symmetry energy at reference densities, we investigate the density dependence of symmetry energy of nuclear matter at subnormal densities. The obtained results are compared with those extracted from other methods.

Liu, Min; Li, Zhuxia; Zhang, Fengshou

2010-01-01T23:59:59.000Z

410

Nuclear symmetry energy at subnormal densities from measured nuclear masses  

E-Print Network (OSTI)

The symmetry energy coefficients for nuclei with mass number A=20~250 are extracted from more than 2000 measured nuclear masses. With the semi-empirical connection between the symmetry energy coefficients of finite nuclei and the nuclear symmetry energy at reference densities, we investigate the density dependence of symmetry energy of nuclear matter at subnormal densities. The obtained results are compared with those extracted from other methods.

Min Liu; Ning Wang; Zhuxia Li; Fengshou Zhang

2010-11-17T23:59:59.000Z

411

Constraints on primordial density perturbations from induced gravitational waves  

SciTech Connect

We consider the stochastic background of gravitational waves produced during the radiation-dominated hot big bang as a constraint on the primordial density perturbation on comoving length scales much smaller than those directly probed by the cosmic microwave background or large-scale structure. We place weak upper bounds on the primordial density perturbation from current data. Future detectors such as BBO and DECIGO will place much stronger constraints on the primordial density perturbation on small scales.

Assadullahi, Hooshyar; Wands, David [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth PO1 3FX (United Kingdom)

2010-01-15T23:59:59.000Z

412

Method for measuring the density of lightweight materials  

DOE Patents (OSTI)

This invention relates to a nondestructive method for measuring the density of articles composed of elements having a low atomic number such as plastic and carbon composites. The measurement is accomplished by striking the article with a collimated beam of X radiation, simultaneously monitoring the radiation scattered and the radiation transmitted by the article, then relating the ratio of the radiation scattered to the radiation transmitted with the density of the article. The above method is insensitive to all variables except density.

Snow, Samuel G. (Oak Ridge, TN); Giacomelli, Edward J. (Knoxville, TN)

1980-01-01T23:59:59.000Z

413

Method for solvent extraction with near-equal density solutions  

DOE Patents (OSTI)

Disclosed is a modified centrifugal contactor for separating solutions of near equal density. The modified contactor has a pressure differential establishing means that allows the application of a pressure differential across fluid in the rotor of the contactor. The pressure differential is such that it causes the boundary between solutions of near-equal density to shift, thereby facilitating separation of the phases. Also disclosed is a method of separating solutions of near-equal density.

Birdwell, Joseph F. (Knoxville, TN); Randolph, John D. (Maryville, TN); Singh, S. Paul (Oak Ridge, TN)

2001-01-01T23:59:59.000Z

414

Dynamic radioactive particle source  

SciTech Connect

A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

Moore, Murray E.; Gauss, Adam Benjamin; Justus, Alan Lawrence

2012-06-26T23:59:59.000Z

415

Analysis of pulsed high-density HBr and Cl{sub 2} plasmas: Impact of the pulsing parameters on the radical densities  

Science Conference Proceedings (OSTI)

The dynamic of charged particles in pulsed plasma is relatively well known since the 1990s. In contrast, works reporting on the impact of the plasma modulation frequency and duty cycle on the radicals' densities are scarce. In this work, we analyze the impact of these modulation parameters on the radicals' composition in Cl{sub 2} and HBr plasmas. The radicals' densities are measured by broad-band UV and vacuum-ultraviolet (VUV) absorption spectroscopy and modulated-beam mass spectrometry. We show that pulsing the rf power allows controlling the plasma chemistry and gives access to the plasma conditions that cannot be reached in continuous wave plasmas. In particular, we show that above 500 Hz, the pulsing frequency has no influence on the plasma chemistry, whereas in contrast the duty cycle is an excellent knob to control the fragmentation of the parent gas, thus the chemical reactivity of the discharge. At low duty cycle, a reduced gas fragmentation combined with a large ion flux leads to new etching conditions, compared to cw plasmas and the expected consequences on pulsed-etching processes are discussed.

Bodart, P.; Brihoum, M.; Cunge, G.; Joubert, O.; Sadeghi, N. [Laboratoire des Technologies de la Microelectronique, CNRS-LTM, 17 rue des Martyrs, Grenoble 38054 (France)

2011-12-01T23:59:59.000Z

416

Effect of Chemical Pressure on the Charge Density Wave Transition...  

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

at SSRL and the department of Applied Physics at Stanford University has determined the phase diagram of a new family of prototypical charge density wave (CDW) compounds. These...

417

Few transportation fuels surpass the energy densities of gasoline ...  

U.S. Energy Information Administration (EIA)

Natural gas, either in liquefied form (LNG) or compressed (CNG), are lighter than gasoline but again have lower densities per unit volume.

418

Few transportation fuels surpass the energy densities of ...  

U.S. Energy Information Administration (EIA)

Energy density and the cost, weight, and size of onboard energy storage are important characteristics of fuels for transportation. Fuels that require ...

419

Inexpensive Production of High Density Thin Ceramic Films on ...  

Steven Visco, Lutgard DeJonghe, and Craig Jacobson have developed a simple, inexpensive method for producing high density, crack-free, thin ceramic ...

420

047 Glass-Ceramic Composites for High Energy Density Capacitors  

Science Conference Proceedings (OSTI)

047 Glass-Ceramic Composites for High Energy Density Capacitors .... 150 Analysis of Hf-Ta Alloys for Oxidation Protection in Ultra High Temperature ...

Note: This page contains sample records for the topic "dynamics md density" 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

Vibrated Bulk Density (VBD) of Calcined Petroleum Coke and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Vibrated Bulk Density (VBD) of Calcined Petroleum Coke and Implications of Changes in the ASTM Method D4292. Author(s), Bill Spencer, ...

422

LINDENS: A program for lineament length and density ...  

Science Conference Proceedings (OSTI)

... or horizontal strata, lineaments are related to fractures and faults ... give an idea of the fracture pattern of ... and density analysis of recent fracturing in the ...

2013-07-15T23:59:59.000Z

423

Variational Two-electron Reduced Density Matrix Theory for Many ...  

E-Print Network (OSTI)

Sep 16, 2005 ... Abstract: The energy and properties of a many-electron atom or ... of a two- electron reduced density matrix (2-RDM) that is constrained to ...

424

The Reduced Density Matrix Method for Electronic Structure ...  

E-Print Network (OSTI)

Oct 14, 2003 ... This suggested to Mayer that the ground state energy. – and density matrix information – could be economically computed by simply carrying ...

425

The Materials Project: Combining Density Functional Theory Calculation...  

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

The Materials Project The Materials Project: Combining Density Functional Theory Calculations with Supercomputing Centers for New Materials Discovery May 2, 2013 jain2 Anubhav Jain...

426

City of Seattle - Density Bonus for Green Buildings (Washington...  

Open Energy Info (EERE)

Edit with form History Share this page on Facebook icon Twitter icon City of Seattle - Density Bonus for Green Buildings (Washington) This is the approved revision of...

427

Aluminum Oxynitride Dielectrics for High Energy Density Capacitor ...  

Science Conference Proceedings (OSTI)

Oct 15, 2006 ... Aluminum Oxynitride Dielectrics for High Energy Density Capacitor Applications by Kevin R. Bray, Richard L.C. Wu, Sandra Fries-Carr, and ...

428

Hybrid Aluminum-Lithium Ion Battery having Enhanced Power Density  

Hybrid Aluminum-Lithium Ion Battery having Enhanced Power Density Note: The technology described above is an early stage opportunity. Licensing rights to this ...

429

Device Fabrication Method for High Power Density Capacitors  

Device Fabrication Method for High Power Density Capacitors Note: The technology described above is an early stage opportunity. Licensing rights to this intellectual ...

430

First-Principles Density Functional Theory Study of Grain Boundary ...  

Science Conference Proceedings (OSTI)

Presentation Title, First-Principles Density Functional Theory Study of Grain ... It was found that both the vacancy formation energy and diffusion activation ...

431

3-D capacitance density imaging of fluidized bed  

DOE Patents (OSTI)

A three-dimensional capacitance density imaging of a gasified bed or the like in a containment vessel is achieved using a plurality of electrodes provided circumferentially about the bed in levels and along the bed in channels. The electrodes are individually and selectively excited electrically at each level to produce a plurality of current flux field patterns generated in the bed at each level. The current flux field patterns are suitably sensed and a density pattern of the bed at each level determined. By combining the determined density patterns at each level, a three-dimensional density image of the bed is achieved.

Fasching, George E. (653 Vista Pl., Morgantown, WV 26505)

1990-01-01T23:59:59.000Z

432

CORRELATION BETWEEN GROUP LOCAL DENSITY AND GROUP LUMINOSITY  

SciTech Connect

In this study, we investigate the correlation between group local number density and total luminosity of groups. In four volume-limited group catalogs, we can conclude that groups with high luminosity exist preferentially in high-density regions, while groups with low luminosity are located preferentially in low-density regions, and that in a volume-limited group sample with absolute magnitude limit M{sub r} = -18, the correlation between group local number density and total luminosity of groups is the weakest. These results basically are consistent with the environmental dependence of galaxy luminosity.

Deng Xinfa [School of Science, Nanchang University, Jiangxi 330031 (China); Yu Guisheng [Department of Natural Science, Nanchang Teachers College, Jiangxi 330103 (China)

2012-11-10T23:59:59.000Z

433

Amplifying Magnetic Fields in High Energy Density Plasmas | U...  

Office of Science (SC) Website

Amplifying Magnetic Fields in High Energy Density Plasmas Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities...

434

HIGH ENERGY DENSITY ALUMINUM BATTERY - Energy Innovation Portal  

Compositions and methods of making are provided for a high energy density aluminum battery. The battery comprises an anode comprising aluminum metal. The battery ...

435

Beat-wave heating with density profile steepening  

SciTech Connect

Electron heating by the beat between 0.53 and 1.06 ..mu..m light in a self-consistently steepened density profile is examined.

Kruer, W.L.; Estabrook, K.

1986-10-01T23:59:59.000Z

436

Compressive Properties of Low Relative Density Materials, Both ...  

Science Conference Proceedings (OSTI)

Abstract Scope, The compressive constitutive behavior of low relatively density materials bas been characterized for various materials. It has been seen that ...

437

Optimization Online - The Reduced Density Matrix Method for ...  

E-Print Network (OSTI)

Oct 16, 2003 ... The Reduced Density Matrix Method for Electronic Structure Calculations ... Calculations of the ground state energy and the dipole moment are ...

438

Mobility of electrons in supercritical krypton: Role of density...  

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

in the scattering cross section at an intermediate field strength. A minimum in the electron mobility was observed at about one-half the critical density. The acoustical...

439

Anomalously High Density of Adsorbed Hydrogen on Surface ...  

Science Conference Proceedings (OSTI)

The amount of adsorbed hydrogen at 20 K under relative pressure = 0.9 was about 11 mass%, indicating that the hydrogen density of the adsorbed state should ...

440

Particle injection into a chain: decoherence versus relaxation for Hermitian and non-Hermitian dynamics  

E-Print Network (OSTI)

We investigate a model system for the injection of fermionic particles from filled source sites into an empty chain. We study the ensuing dynamics for Hermitian as well as for non-Hermitian time evolution where the particles cannot return to the bath sites (quantum ratchet). A non-homogeneous hybridization between bath and chain sites permits transient currents in the chain. Non-interacting particles show decoherence in the thermodynamic limit: the average particle number and the average current density in the chain become stationary for long times, whereas the single-particle density matrix displays large fluctuations around its mean value. Using the numerical time-dependent density-matrix renormalization group ($t$-DMRG) method we demonstrate, on the other hand, that sizable density-density interactions between the particles introduce relaxation which is by orders of magnitudes faster than the decoherence processes.

F. Gebhard; K. zu Muenster; J. Ren; N. Sedlmayr; J. Sirker; B. Ziebarth

2011-10-24T23:59:59.000Z

Note: This page contains sample records for the topic "dynamics md density" 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
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441

An Efficient and Accurate Car-Parrinello-like Approach to Born-Oppenheimer Molecular Dynamics  

E-Print Network (OSTI)

We present a new method which combines Car-Parrinello and Born-Oppenheimer molecular dynamics in order to accelerate density functional theory based ab-initio simulations. Depending on the system a gain in efficiency of one to two orders of magnitude has been observed, which allows ab-initio molecular dynamics of much larger time and length scales than previously thought feasible. It will be demonstrated that the dynamics is correctly reproduced and that high accuracy can be maintained throughout for systems ranging from insulators to semiconductors and even to metals in condensed phases. This development considerably extends the scope of ab-initio simulations.

Thomas D. Kühne; Matthias Krack; Fawzi R. Mohamed; Michele Parrinello

2006-10-19T23:59:59.000Z

442

Dynamic compaction of tungsten carbide powder.  

Science Conference Proceedings (OSTI)

The shock compaction behavior of a tungsten carbide powder was investigated using a new experimental design for gas-gun experiments. This design allows the Hugoniot properties to be measured with reasonably good accuracy despite the inherent difficulties involved with distended powders. The experiments also provide the first reshock state for the compacted powder. Experiments were conducted at impact velocities of 245, 500, and 711 m/s. A steady shock wave was observed for some of the sample thicknesses, but the remainder were attenuated due to release from the back of the impactor or the edge of the sample. The shock velocity for the powder was found to be quite low, and the propagating shock waves were seen to be very dispersive. The Hugoniot density for the 711 m/s experiment was close to ambient crystal density for tungsten carbide, indicating nearly complete compaction. When compared with quasi-static compaction results for the same material, the dynamic compaction data is seen to be significantly stiffer for the regime over which they overlap. Based on these initial results, recommendations are made for improving the experimental technique and for future work to improve our understanding of powder compaction.

Gluth, Jeffrey Weston; Hall, Clint Allen; Vogler, Tracy John; Grady, Dennis Edward

2005-04-01T23:59:59.000Z

443

Meeting Residential Ventilation Standards Through Dynamic Control...  

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

Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation Systems Title Meeting Residential Ventilation Standards Through Dynamic Control of Ventilation...

444

Maps and inverse maps in open quantum dynamics  

Science Conference Proceedings (OSTI)

Two kinds of maps that describe evolution of states of a subsystem coming from dynamics described by a unitary operator for a larger system, maps defined for fixed mean values and maps defined for fixed correlations, are found to be quite different for the same unitary dynamics in the same situation in the larger system. An affine form is used for both kinds of maps to find necessary and sufficient conditions for inverse maps. All the different maps with the same homogeneous part in their affine forms have inverses if and only if the homogeneous part does. Some of these maps are completely positive; others are not, but the homogeneous part is always completely positive. The conditions for an inverse are the same for maps that are not completely positive as for maps that are. For maps defined for fixed mean values, the homogeneous part depends only on the unitary operator for the dynamics of the larger system, not on any state or mean values or correlations. Necessary and sufficient conditions for an inverse are stated several different ways: in terms of the maps of matrices, basis matrices, density matrices, or mean values. The inverse maps are generally not tied to the dynamics the way the maps forward are. A trace-preserving completely positive map that is unital cannot have an inverse that is obtained from any dynamics described by any unitary operator for any states of a larger system.

Jordan, Thomas F., E-mail: tjordan@d.umn.ed [Physics Department, University of Minnesota, Duluth, MN 55812 (United States)

2010-10-15T23:59:59.000Z

445

STRAIGHTENING THE DENSITY-DISPLACEMENT RELATION WITH A LOGARITHMIC TRANSFORM  

Science Conference Proceedings (OSTI)

We investigate the use of a logarithmic density variable in estimating the Lagrangian displacement field motivated by the success of a logarithmic transformation in restoring information to the matter power spectrum. The logarithmic relation is an extension of the linear relation, motivated by the continuity equation, in which the density field is assumed to be proportional to the divergence of the displacement field; we compare the linear and logarithmic relations by measuring both of these fields directly in a cosmological N-body simulation. The relative success of the logarithmic and linear relations depends on the scale at which the density field is smoothed. Thus we explore several ways of measuring the density field, including Cloud-In-Cell smoothing, adaptive smoothing, and the (scale-independent) Delaunay tessellation, and we use both a Fourier-space and a geometrical tessellation approach to measuring the divergence. We find that the relation between the divergence of the displacement field and the density is significantly tighter and straighter with a logarithmic density variable, especially at low redshifts and for very small ({approx}2 h{sup -1} Mpc) smoothing scales. We find that the grid-based methods are more reliable than the tessellation-based method of calculating both the density and the divergence fields, though in both cases the logarithmic relation works better in the appropriate regime, which corresponds to nonlinear scales for the grid-based methods and low densities for the tessellation-based method.

Falck, Bridget L.; Neyrinck, Mark C.; Aragon-Calvo, Miguel A.; Lavaux, Guilhem; Szalay, Alexander S. [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles St., Baltimore, MD 21218 (United States)

2012-01-20T23:59:59.000Z

446

Alternative representation of N \\times N density matrix  

E-Print Network (OSTI)

We use polarization operators known from quantum theory of angular momentum to expand the $N \\times N$ dimensional density operators. Thereby, we construct generalized Bloch vectors representing density matrices. We study their properties and derive positivity conditions for any $N$. We also apply the procedure to study Bloch vector space for a qubit and a qutrit.

Stanislaw Kryszewski; Mateusz Zachcial

2006-02-06T23:59:59.000Z

447

Energy density for chiral lattice fermions with chemical potential  

E-Print Network (OSTI)

We study a recently proposed formulation of overlap fermions at finite density. In particular we compute the energy density as a function of the chemical potential and the temperature. It is shown that overlap fermions with chemical potential reproduce the correct continuum behavior.

Gattringer, Christof

2007-01-01T23:59:59.000Z

448

Measurement on CO_2 Solution Density by Optical Technology  

Science Conference Proceedings (OSTI)

The optical technology based on Mach-Zehnder interferometry was successfully applied to a high-pressure liquid CO_2 and water system to measure CO_2 solution density. Experiments were carried out at a pressure range of from 5.0 to 12.5 MPa, temperatures ... Keywords: CO_2 ocean sequestration, CO_2 solution, Mach-Zehnder Interferometry, density

Y. Song; M. Nishio; B. Chen; S. Someya; T. Ohsumi

2003-01-01T23:59:59.000Z

449

OPTIMIZATION OF LAYER DENSITIES FOR MULTILAYERED INSULATION SYSTEMS  

Science Conference Proceedings (OSTI)

Numerous tests of various multilayer insulation systems have indicated that there are optimal densities for these systems. However, the only method of calculating this optimal density was by a complex physics based algorithm developed by McIntosh. In the 1970's much data were collected on the performance of these insulation systems with many different variables analyzed. All formulas generated included number of layers and layer density as geometric variables in solving for the heat flux, none of them was in a differentiable form for a single geometric variable. It was recently discovered that by converting the equations from heat flux to thermal conductivity using Fourier's Law, the equations became functions of layer density, temperatures, and material properties only. The thickness and number of layers of the blanket were merged into a layer density. These equations were then differentiated with respect to layer density. By setting the first derivative equal to zero, and solving for the layer density, the critical layer density was determined. This method was checked and validated using test data from the Multipurpose Hydrogen Testbed which was designed using Mcintosh's algorithm.

Johnson, W. L. [NASA Kennedy Space Center, KT-E Kennedy Space Center, FL 32899 (United States)

2010-04-09T23:59:59.000Z

450

The spectral density of the scattering matrix for high energies  

E-Print Network (OSTI)

We determine the density of eigenvalues of the scattering matrix of the Schrodinger operator with a short range potential in the high energy asymptotic regime. We give an explicit formula for this density in terms of the X-ray transform of the potential.

Daniel Bulger; Alexander Pushnitski

2011-10-17T23:59:59.000Z

451

The spectral density of the scattering matrix for high energies  

E-Print Network (OSTI)

We determine the density of eigenvalues of the scattering matrix of the Schrodinger operator with a short range potential in the high energy asymptotic regime. We give an explicit formula for this density in terms of the X-ray transform of the potential.

Bulger, Daniel

2011-01-01T23:59:59.000Z

452

Generalized Look-Ahead Methods for Computing Stationary Densities  

Science Conference Proceedings (OSTI)

The look-ahead estimator is used to compute densities associated with Markov processes via simulation. We study a framework that extends the look-ahead estimator to a broader range of applications. We provide a general asymptotic theory for the estimator, ... Keywords: densities, numerical methods, simulation

R. Anton Braun; Huiyu Li; John Stachurski

2012-08-01T23:59:59.000Z

453

Mixed Layer Density Ratio from the Levitus Data  

Science Conference Proceedings (OSTI)

An analysis of the Levitus data is employed to examine Stommel's mixed layer density ratio regulator hypothesis. Three different methods of computing the lateral density ratio (Rl???T/??S) are used and the least squares method was found to have ...

Liang Gui Chen

1995-04-01T23:59:59.000Z

454

Vacancy Mechanism Davydov I.А.  

National Nuclear Security Administration (NNSA)

9: Computational Physics-MD 9: Computational Physics-MD DFT and MD Simulation of Self-Diffusion in Silicon: Study of Diffusion Vacancy Mechanism Davydov I.А. * , Anisin А.V. † , Eliseev G.М. ‡ , Kopkin S.V. § , and Reese Jones ** *, †, ‡, § Russian Federal Nuclear Center - All-Russia Research Institute of Experimental Physics (RFNC-VNIIEF), 607190 Sarov, Mira-37, Russia ** Sandia National Laboratories, MS 9404, P.O. Box 0969, Livermore, CA 94551, USA Summary: Computations of jump activation energy DH j and diffusion jump frequency n have been carried out using the Density Functional Theory (DFT) and Molecular Dynamics (MD) method for a single crystal of Si. These parameters define the rate of vacancy diffusion transport.

455

Folding of a DNA Hairpin Loop Structure in Explicit Solvent Using Replica-Exchange Molecular Dynamics Simulations.  

DOE Green Energy (OSTI)

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. Hairpin loop structures are common motifs in folded nucleic acids. The 59-GCGCAGC sequence in DNA forms a characteristic and stable trinucleotide hairpin loop flanked by a two basepair stem helix. To better understand the structure formation of this hairpin loop motif in atomic detail, we employed replica-exchange molecular dynamics (RexMD) simulations starting from a single-stranded DNA conformation. In two independent 36 ns RexMD simulations, conformations in very close agreement with the experimental hairpin structure were sampled as dominant conformations (lowest free energy state) during the final phase of the RexMDs (;35% at the lowest temperature replica). Simultaneous compaction and accumulation of folded structures were observed. Comparison of the GCA trinucleotides from early stages of the simulations with the folded topology indicated a variety of central loop conformations, but arrangements close to experiment that are sampled before the fully folded structure also appeared. Most of these intermediates included a stacking of the C2 and G3 bases, which was further stabilized by hydrogen bonding to the A5 base and a strongly bound water molecule bridging the C2 and A5 in the DNA minor groove. The simulations suggest a folding mechanism where these intermediates can rapidly proceed toward the fully folded hairpin and emphasize the importance of loop and stem nucleotide interactions for hairpin folding. In one simulation, a loop motif with G3 in syn conformation (dihedral flip at N-glycosidic bond) accumulated, resulting in a misfolded hairpin. Such conformations may correspond to long-lived trapped states that have been postulated to account for the folding kinetics of nucleic acid hairpins that are slower than expected for a semiflexible polymer of the same size.

Kannan, Srinivasaraghavan; Zacharias, Martin W.

2007-11-01T23:59:59.000Z

456

Extended Lagrangian quantum molecular dynamics simulations of shock-induced chemistry in hydrocarbons  

SciTech Connect

A set of interatomic potentials for hydrocarbons that are based upon the self-consistent charge transfer tight-binding approximation to density functional theory have been developed and implemented into the quantum molecular dynamics code ''LATTE''. The interatomic potentials exhibit an outstanding level of transferability and have been applied in molecular dynamics simulations of tert-butylacetylene under thermodynamic conditions that correspond to its single-shock Hugoniot. We have achieved precise conservation of the total energy during microcanonical molecular dynamics trajectories under incomplete convergence via the extended Lagrangian Born-Oppenheimer molecular dynamics formalism. In good agreement with the results of a series of flyer-plate impact experiments, our SCC-TB molecular dynamics simulations show that tert-butylactylene molecules polymerize at shock pressures around 6.1 GPa.

Sanville, Edward J [Los Alamos National Laboratory; Bock, Nicolas [Los Alamos National Laboratory; Challacombe, William M [Los Alamos National Laboratory; Cawkwell, Marc J [Los Alamos National Laboratory; Niklasson, Anders M N [Los Alamos National Laboratory; Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Stephen [Los Alamos National Laboratory; Sewell, Thomas D [UNIV OF MISSOURI

2010-01-01T23:59:59.000Z

457

Euler & Lagrange versus Heisenberg & Schroedinger: Dynamical Pictures in Classical and Quantum Mechanics  

E-Print Network (OSTI)

Using quantum-classical analogies, we find that dynamical pictures of quantum mechanics have precise counterparts in classical mechanics. In particular, the Eulerian and Lagrangian descriptions of fluid dynamics in classical mechanics are the analogs of the Schroedinger and Heisenberg pictures in quantum mechanics, respectively. Similarities between classical and quantum dynamical pictures are explored within the framework of the Koopman-von Neumann formalism. These allow for a natural definition of various dynamical pictures in classical mechanics as well as the application of classical concepts to quantum dynamics. As an illustration, we use the interaction picture to find the classical evolution of an ensemble of particles of equal initial momenta and arbitrary configuration density under the action of a constant force in one dimension. As a second example, we discuss the extension of the ideas of sensitivity to initial conditions and chaos in classical mechanics to quantum mechanics.

M. Hossein Partovi

2013-05-22T23:59:59.000Z

458

How glassy are orientational dynamics of rodlike molecules near the isotropic-nematic transition?  

E-Print Network (OSTI)

In an attempt to quantitatively characterize the recently observed slow dynamics in the isotropic and nematic phase of liquid crystals, we investigate the single-particle orientational dynamics of rodlike molecules across the isotropic-nematic transition in computer simulations of a family of model systems of thermotropic liquid crystals. Several remarkable features of glassy dynamics are on display including non-exponential relaxation, dynamical heterogeneity, and non-Arrhenius temperature dependence of the orientational relaxation time. In order to obtain a quantitative measure of glassy dynamics in line with the estbalished methods in supercooled liquids, we construct a relaxation time versus scaled inverse temperature plot, and demonstrate that one can indeed define a 'fragility index' for thermotropic liquid crystals, that depends on density and aspect ratio. The values of the fragility parameter are surprisingly in the range one observed for glass forming liquids. A plausible correlation between the energy landscape features and the observed fragility is discussed.

Biman Jana; Dwaipayan Chakrabarti; Biman Bagchi

2007-03-06T23:59:59.000Z

459

Innovative High Energy Density Capacitor Design Offers Potential for Clean  

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

High Energy Density Capacitor Design Offers Potential High Energy Density Capacitor Design Offers Potential for Clean Energy Applications Innovative High Energy Density Capacitor Design Offers Potential for Clean Energy Applications June 10, 2011 - 4:46pm Addthis Similar system to the clustering tool that will manufacture TroyCap’s High Energy Density Nanolaminate Capacitor | Credit: TroyC Similar system to the clustering tool that will manufacture TroyCap's High Energy Density Nanolaminate Capacitor | Credit: TroyC Ben Squires Analyst, Office of Energy Efficiency & Renewable Energy Can you imagine a photovoltaic module that's able to generate and store electricity on its own? Or an electric vehicle (EV) powered by a technology more durable than the advanced batteries in today's EVs? Malvern, Pennsylvania's TroyCap, LLC is using nanolaminate technology patented by

460

Innovative High Energy Density Capacitor Design Offers Potential for Clean  

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

Innovative High Energy Density Capacitor Design Offers Potential Innovative High Energy Density Capacitor Design Offers Potential for Clean Energy Applications Innovative High Energy Density Capacitor Design Offers Potential for Clean Energy Applications June 10, 2011 - 4:46pm Addthis Similar system to the clustering tool that will manufacture TroyCap’s High Energy Density Nanolaminate Capacitor | Credit: TroyC Similar system to the clustering tool that will manufacture TroyCap's High Energy Density Nanolaminate Capacitor | Credit: TroyC Ben Squires Analyst, Office of Energy Efficiency & Renewable Energy Can you imagine a photovoltaic module that's able to generate and store electricity on its own? Or an electric vehicle (EV) powered by a technology more durable than the advanced batteries in today's EVs? Malvern,

Note: This page contains sample records for the topic "dynamics md density" 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

Rock Density At Alum Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

Rock Density At Alum Area (DOE GTP) Rock Density At Alum Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Density At Alum Geothermal Area (DOE GTP) Exploration Activity Details Location Alum Geothermal Area Exploration Technique Rock Density Activity Date Usefulness not indicated DOE-funding Unknown References (1 January 2011) GTP ARRA Spreadsheet Retrieved from "http://en.openei.org/w/index.php?title=Rock_Density_At_Alum_Area_(DOE_GTP)&oldid=402985" Categories: Exploration Activities DOE Funded Activities ARRA Funded Activities What links here Related changes Special pages Printable version Permanent link Browse properties About us Disclaimers Energy blogs Linked Data Developer services OpenEI partners with a broad range of international organizations to grow

462

Definition: Dynamic Interchange Schedule Or Dynamic Schedule | Open Energy  

Open Energy Info (EERE)

Schedule Or Dynamic Schedule Schedule Or Dynamic Schedule Jump to: navigation, search Dictionary.png Dynamic Interchange Schedule Or Dynamic Schedule A telemetered reading or value that is updated in real time and used as a schedule in the AGC/ACE equation and the integrated value of which is treated as a schedule for interchange accounting purposes. Commonly used for scheduling jointly owned generation to or from another Balancing Authority Area.[1] Related Terms balancing authority, balancing authority area, smart grid References ↑ Glossary of Terms Used in Reliability Standards 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:Dynamic_Interchange_Schedule_Or_Dynamic_Schedule&oldid=502492

463

Dynamic chamber armor behavior in IFE and MFE A.R. Raffray a,  

E-Print Network (OSTI)

Dynamic chamber armor behavior in IFE and MFE A.R. Raffray a, 1, G. Federici b , A. Hassanein c , D., Madison, WI 53706-1687, USA Abstract The chamber wall armor is subject to demanding conditions in both the requirements on armor imposed by the operating conditions in IFE and MFE, including energy deposition density

Raffray, A. René

464

Application of system dynamics, GIS and 3D visualization in a study of residential sustainability  

Science Conference Proceedings (OSTI)

Constructing and improving urban residential areas is an eternal critical subject in the process of the whole urban development which is connected with a series of challenges and problems. In this paper, firstly DPSIR (Driving Forces-Pressure-State-Impact-Response) ... Keywords: 3D visualization, GIS, cityengine, density map, residential areas, sustainability, system dynamics model

Zhao Xu; Volker Coors

2011-06-01T23:59:59.000Z

465

Study of nuclear dynamics of neutron-rich colliding pair at energy of vanishing flow  

E-Print Network (OSTI)

We study nuclear dynamics at the energy of vanishing flow of neutron-rich systems having N/Z ratio 1.0, 1.6 and 2.0 throughout the mass range at semi central colliding geometry. In particular we study the behavior of average and maximum density with N/Z dependence of the system.

Sakshi Gautam

2011-07-28T23:59:59.000Z

466

The dynamic conductivity of strongly non-ideal plasmas: is the Drude model valid?  

E-Print Network (OSTI)

The method of moments is used to calculate the dynamic conductivity of strongly coupled fully ionized hydrogen plasmas. The electron density $n_{e}$ and temperature $T$ vary in the domains $ 10^{21} < n_{e} < 10^{24} {\\rm cm}^{-3}$, $10^{4} {\\rm K} < T < 10^{6} {\\rm K}$. The results are compared to some theoretical data.

Adamyan, V M; Sakan, N M; Sreckovic, V A; Tkachenko, I M; 10.1088/1751-8113/42/21/214005

2013-01-01T23:59:59.000Z

467

The dynamic conductivity of strongly non-ideal plasmas: is the Drude model valid?  

E-Print Network (OSTI)

The method of moments is used to calculate the dynamic conductivity of strongly coupled fully ionized hydrogen plasmas. The electron density $n_{e}$ and temperature $T$ vary in the domains $ 10^{21} < n_{e} < 10^{24} {\\rm cm}^{-3}$, $10^{4} {\\rm K} < T < 10^{6} {\\rm K}$. The results are compared to some theoretical data.

V. M. Adamyan; A. A. Mihajlov; N. M. Sakan; V. A. Sreckovic; I. M. Tkachenko

2013-03-03T23:59:59.000Z

468

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

469

Graphene as a quantum surface with curvature-strain preserving dynamics  

E-Print Network (OSTI)

We discuss how the curvature and the strain density of the atomic lattice generate the quantization of graphene sheets as well as the dynamics of geometric quasiparticles propagating along the constant curvature/strain levels. The internal kinetic momentum of Riemannian oriented surface (a vector field preserving the Gaussian curvature and the area) is determined.

M. V. Karasev

2010-11-10T23:59:59.000Z

470

Heat transfer dynamics  

Science Conference Proceedings (OSTI)

As heat transfer technology increases in complexity, it becomes more difficult for those without thermal dynamics engineering training to choose between competitive heat transfer systems offered to meet their drying requirements. A step back to the basics of heat transfer can help professional managers and papermakers make informed decisions on alternative equipment and methods. The primary forms of heat and mass transfer are reviewed with emphasis on the basics, so a practical understanding of each is gained. Finally, the principles and benefits of generating infrared energy by combusting a gaseous hydrocarbon fuel are explained.

Smith, T.M. (Marsden, Inc., Pennsauken, NJ (United States))

1994-08-01T23:59:59.000Z

471

Ab initio molecular dynamics simulations of ion–solid interactions in Gd2Zr2O7 and Gd2Ti2O7  

Science Conference Proceedings (OSTI)

The development of the ab initio molecular dynamics (AIMD) method has made it a powerful tool in describing ion–solid interactions in materials, with the determination of threshold displacement energies with ab initio accuracy, and prediction of a new mechanism for defect generation and new defective states that are different from classical molecular dynamics (MD) simulations. In the present work, this method is employed to study the low energy recoil events in Gd2Zr2O7 and Gd2Ti2O7. The weighted average threshold displacement energies in Gd2Zr2O7 are determined to be 38.8 eV for Gd, 41.4 eV for Zr, 18.6 eV for O48f, and 15.6 eV for O8b, which are smaller than the respective values of 41.8, >53.8, 22.6 and 16.2 eV in Gd2Ti2O7. It reveals that all the ions in Gd2Zr2O7 are more easily displaced than those in Gd2Ti2O7, and anion order–disorder is more likely to be involved in the displacement events than cation disordering. The average charge transfer from the primary knock-on atom to its neighbors is estimated to be [similar]0.15, [similar]0.11 to 0.27 and [similar]0.1 to 0.13 |e| for Gd, Zr (or Ti), and O, respectively. Neglecting the charge transfer in the interatomic potentials may result in the larger threshold displacement energies in classical MD.

Wang, X. J.; Xiao, Haiyan Y.; Zu, Xiaotao; Zhang, Yanwen; Weber, William J.

2012-12-21T23:59:59.000Z

472

Ab initio molecular dynamics simulations of ion-solid interactions in Gd2Zr2O7 and Gd2Ti2O7  

SciTech Connect

The development of ab initio molecular dynamics (AIMD) method has made it a powerful tool in describing ion-solid interactions in materials, with identification determination of threshold displacement energies with ab initio accuracy, and prediction of new mechanism for defect generation and new defective states that are different from classical molecular dynamics (MD) simulations. In the present work, this method is employed to study the low energy recoil events in Gd2Zr2O7 and Gd2Ti2O7. The weighted average threshold displacement energies in Gd2Zr2O7 are determined to be 38.8 eV for Gd, 41.4 eV for Zr, 18.6 eV for O48f, and 15.6 eV for O8b, which are smaller than the respective values of 41.8, >53.8, 22.6 and 16.2 eV in Gd2Ti2O7. It reveals that all the ions in Gd2Zr2O7 are more easily displaced than those in Gd2Ti2O7, and anion order-disorder are more likely to be involved in the displacement events than cation disordering. The average charge transfer from the primary knock-on atom to its neighbors is estimated to be ~0.15, ~0.11-0.27 and ~0.1-0.13 |e| for Gd, Zr (or Ti), and O, respectively. Negligence of the charge transfer in the interatomic potentials may result in the larger threshold displacement energies in classical MD.

Wang, X J [University of Electronic Science and Technology of China (UESTC); Xiao, Haiyan [University of Tennessee, Knoxville (UTK); Zu, X T [University of Electronic Science and Technology of China (UESTC); Zhang, Yanwen [ORNL; Weber, William J [ORNL

2013-01-01T23:59:59.000Z

473

Dynamic Chirality in Nuclei  

SciTech Connect

The possible chiral interpretation of twin bands in odd-odd nuclei was investigated in the Interacting Boson Fermion-Fermion Model. The analysis of the wave functions has shown that the possibility for angular momenta of the valence proton, neutron and core to find themselves in the favorable, almost orthogonal geometry is present, but not dominant. Such behaviour is found to be similar in nuclei where both the level energies and the electromagnetic decay properties display the chiral pattern, as well as in those where only the energies of the corresponding levels in the twin bands are close together. The difference in the structure of the two types of chiral candidates nuclei can be attributed to different beta and gamma fluctuations, induced by the exchange boson-fermion interaction of the Interacting Boson Fermion-Fermion Model. In both cases the chirality is weak and dynamic. The existence of doublets of bands in {sup 134}Pr can be attributed to dynamic chirality dominated by shape fluctuations.

Tonev, D. [Institute for Nuclear Research and Nuclear Energy, BAS, 1784 Sofia (Bulgaria); INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Angelis, G. de [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Brant, S. [Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia); Petkov, P. [Institute for Nuclear Research and Nuclear Energy, BAS, 1784 Sofia (Bulgaria); Ventura, A. [ENEA, 40129 Bologna and INFN, Sezione di Bologna (Italy)

2009-08-26T23:59:59.000Z

474

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,"

475

Statics and dynamics of inhomogeneous liquids via the internal-energy functional  

E-Print Network (OSTI)

We give a variational formulation of classical statistical mechanics where the one-body density and the local entropy distribution constitute the trial fields. Using Levy's constrained search method it is shown that the grand potential is a functional of both distributions, that it is minimal in equilibrium, and that the minimizing fields are those at equilibrium. The functional splits into a sum of entropic, external energetic and internal energetic contributions. Several common approximate Helmholtz free energy density functionals, such as the Rosenfeld fundamental measure theory for hard sphere mixtures, are transformed to internal energy functionals. The variational derivatives of the internal energy functional are used to generalize dynamical density functional theory to include the dynamics of the microscopic entropy distribution, as is relevant for studying heat transport and thermal diffusion.

Matthias Schmidt

2011-10-20T23:59:59.000Z

476

Density Changes in the Optimized CSSX Solvent System  

Science Conference Proceedings (OSTI)

Density increases in caustic-side solvent extraction (CSSX) solvent have been observed in separate experimental programs performed by different groups of researchers. Such changes indicate a change in chemical composition. Increased density adversely affects separation of solvent from denser aqueous solutions present in the CSSX process. Identification and control of factors affecting solvent density are essential for design and operation of the centrifugal contactors. The goals of this research were to identify the factors affecting solvent density (composition) and to develop correlations between easily measured solvent properties (density and viscosity) and the chemical composition of the solvent, which will permit real-time determination and adjustment of the solvent composition. In evaporation experiments, virgin solvent was subjected to evaporation under quiescent conditions at 25, 35, and 45 C with continuously flowing dry air passing over the surface of the solvent. Density and viscosity were measured periodically, and chemical analysis was performed on the solvent samples. Chemical interaction tests were completed to determine if any chemical reaction takes place over extended contact time that changes the composition and/or physical properties. Solvent and simulant, solvent and strip solution, and solvent and wash solution were contacted continuously in agitated flasks. They were periodically sampled and the density measured (viscosity was also measured on some samples) and then submitted to the Chemical Sciences Division of Oak Ridge National Laboratory for analysis by nuclear magnetic resonance (NMR) spectrometry and high-performance liquid chromatography (HPLC) using the virgin solvent as the baseline. Chemical interaction tests showed that solvent densities and viscosities did not change appreciably during contact with simulant, strip, or wash solution. No effects on density and viscosity and no chemical changes in the solvent were noted within experimental limits. Evaporation test results showed that all solvents were evaporated to densities of greater than 0.90 g/cm{sup 3}. Viscosities increased from 3.5 to >6.5 cP as the densities increased. NMR and HPLC data indicate that diluent loss is the primary reason for density increase and that the ratio of BOBCalixC6 (referred to as calix) to Cs-7SB remained almost constant. Density and viscosity vary linearly with the loss of diluent and the increase in Cs-7SB concentration. Solvent viscosity and density are both sensitive indicators of the loss of diluent, especially when such loss is greater than 10%. However, density is more reliable at low values for diluent loss. The ratio of Cs-7SB to calix appears relatively constant during evaporation to losses of more than 50% of the diluent. A simple density model accurately predicts the composition of the solvent when density is known. Density and viscosity increases can affect the throughput in the centrifugal contactors and, at the extreme, can cause complete loss of flow. The distribution coefficient can also increase, especially in the strip stage, causing the loss of the ability to strip extracted cesium from the solvent. These effects can be addressed by internal changes to the contactor and by adding additional stripping stages in processing. However, these changes are extremely difficult under remote operation and maintenance restrictions.

Lee, D.D.

2002-11-25T23:59:59.000Z

477

Particle Dynamics And Emergent Gravity  

E-Print Network (OSTI)

The emergent gravity proposal is examined within the framework of noncommutative QED/gravity correspondence from particle dynamics point of view.

Amir H. Fatollahi

2008-05-08T23:59:59.000Z

478

Nuclear Matter and Nuclear Dynamics  

E-Print Network (OSTI)

Highlights on the recent research activity, carried out by the Italian Community involved in the "Nuclear Matter and Nuclear Dynamics" field, will be presented.

M Colonna

2009-02-26T23:59:59.000Z

479

Dislocation density in copper and tantalum after shock loading up to 20-80 GPa  

National Nuclear Security Administration (NNSA)

4: Materials-EOS and Thermodynamic Properties 4: Materials-EOS and Thermodynamic Properties Dislocation Density in Copper And Tantalum After Shock Loading Up To 20-100 GPA A.M. Podurets, M.I. Tkachenko, O.N. Ignatova, A.I. Lebedev, V.V. Igonin, V.A. Raevsky RFNC-VNIIEF, Institute of Physics of Explosion, Sarov, Russia Introduction A microstructure of metals at shock loading is determined by the same processes, which occur at any deformation including a competition of two basic mechanisms of plastic strain - dislocation slip and twinning. The action of a specified mechanism of plastic deformation under the conditions of dynamic loading is usually defined by the help of the analysis of samples recovered after loading. We consider the dislocation structure of two metals having various crystal lattices: face-centered cubic copper and body-

480

SAND2011-6616A Page 1 Session 2: High Energy Density, Plasmas, Magnetic Fields  

National Nuclear Security Administration (NNSA)

616A 616A Page 1 Session 2: High Energy Density, Plasmas, Magnetic Fields Dynamical Materials Experiments on Sandia's Z Machine: Obtaining Data with High Precision at HED Conditions Thomas R. Mattsson and Seth Root Sandia National Laboratories, Albuquerque, NM USA Summary: The Z machine at Sandia National Laboratories has successfully been used to study a wide range of materials under extreme conditions. In this paper, we will discuss the methodology resulting in high-pressure measurements at multi-Mbar pressures as well as present experimental data for shock compression of poly methyl-pentene, a hydrocarbon plastic. Introduction During the last few years, there has been a notable increase in the interest of high-pressure science. The increase in interest has been driven by the remarkable capabilities of new and improved platforms like

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481

Optimal estimation of free energies and stationary densities from multiple biased simulations  

E-Print Network (OSTI)

When studying high-dimensional dynamical systems such as macromolecules, quantum systems and polymers, a prime concern is the identification of the most probable states and their stationary probabilities or free energies. Often, these systems have metastable regions or phases, prohibiting to estimate the stationary probabilities by direct simulation. Efficient sampling methods such as umbrella sampling, metadynamics and conformational flooding have developed that perform a number of simulations where the system's potential is biased such as to accelerate the rare barrier crossing events. A joint free energy profile or stationary density can then be obtained from these biased simulations with weighted histogram analysis method (WHAM). This approach (a) requires a few essential order parameters to be defined in which the histogram is set up, and (b) assumes that each simulation is in global equilibrium. Both assumptions make the investigation of high-dimensional systems with previously unknown energy landscape ...

Wu, Hao

2013-01-01T23:59:59.000Z

482

Numerical simulations of collisionless drift instabilities for low-density plasmas  

SciTech Connect

Nonlinear behavior of the collisionless drift instabilities are studied for the universal and current driven modes by means of electrostatic particle simulations in two-and-a-half dimensions. Realistic mass ratios of the electrons to the ions are used in the simulations, where the guiding-center approximation for the electrons and the exact dynamics for the ions are employed. Several nonlinear effects including the quasilinear diffusion of the particle density, the frequency shift due to the ambipolar field, the mode competition among the unstable waves, and the quasilinear diffusion in the velocity space are found to be the dominant mechanisms for the saturation. The stabilization of the collisionless drift instabilities by the magnetic shear has also been studied.

Lee, W.W.; Yau, Y.Y.K.; Okuda, H.

1977-10-01T23:59:59.000Z

483

A short remark on negative energy densities and quantum inequalities  

E-Print Network (OSTI)

In quantum field theory it is generally known that the energy density may be negative at a given point in spacetime. A number of papers have shown that there is a restriction on this energy density which is called a quantum inequality (QI). A QI is the lower bound to the "weighted average" of the energy density at a given point integrated over a time dependent sampling function. In this paper we give an example of a sampling function for which there is no QI.

Solomon, Dan

2009-01-01T23:59:59.000Z

484

A short remark on negative energy densities and quantum inequalities  

E-Print Network (OSTI)

In quantum field theory it is generally known that the energy density may be negative at a given point in spacetime. A number of papers have shown that there is a restriction on this energy density which is called a quantum inequality (QI). A QI is the lower bound to the "weighted average" of the energy density at a given point integrated over a time dependent sampling function. In this paper we give an example of a sampling function for which there is no QI.

Dan Solomon

2009-01-05T23:59:59.000Z

485

Nuclear Energy Density Functionals Constrained by Low-Energy QCD  

E-Print Network (OSTI)

A microscopic framework of nuclear energy density functionals is reviewed, which establishes a direct relation between low-energy QCD and nuclear structure, synthesizing effective field theory methods and principles of density functional theory. Guided by two closely related features of QCD in the low-energy limit: a) in-medium changes of vacuum condensates, and b) spontaneous breaking of chiral symmetry; a relativistic energy density functional is developed and applied in studies of ground-state properties of spherical and deformed nuclei.

Vretenar, Dario

2008-01-01T23:59:59.000Z

486

Nuclear Energy Density Functionals Constrained by Low-Energy QCD  

E-Print Network (OSTI)

A microscopic framework of nuclear energy density functionals is reviewed, which establishes a direct relation between low-energy QCD and nuclear structure, synthesizing effective field theory methods and principles of density functional theory. Guided by two closely related features of QCD in the low-energy limit: a) in-medium changes of vacuum condensates, and b) spontaneous breaking of chiral symmetry; a relativistic energy density functional is developed and applied in studies of ground-state properties of spherical and deformed nuclei.

Dario Vretenar

2008-02-06T23:59:59.000Z