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Note: This page contains sample records for the topic "higher energy 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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1

Developing a Lower Cost and Higher Energy Density Alternative...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

for Advanced Batteries ADVANCED MANUFACTURING OFFICE Developing a Lower Cost and Higher Energy Density Alternative to Lithium-Ion Batteries Introduction As the world moves toward...

2

Vehicle Technologies Office Merit Review 2014: Development of Large Format Lithium Ion Cells with Higher Energy Density  

Broader source: Energy.gov [DOE]

Presentation given by XALT Energy LLC at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about development of large format...

3

Development of Large Format Lithium Ion Cells with Higher Energy...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500WhL Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500WhL 2012 DOE...

4

Higher Power Energy LLC | Open Energy Information  

Open Energy Info (EERE)

Higher Power Energy LLC Higher Power Energy LLC Jump to: navigation, search Name Higher Power Energy, LLC Place Flower Mound, Texas Zip 78028 Sector Renewable Energy, Wind energy Product Higher Power Energy is focused on the development and management of renewable wind energy across North America. References Higher Power Energy, LLC[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Higher Power Energy, LLC is a company located in Flower Mound, Texas . References ↑ "Higher Power Energy, LLC" Retrieved from "http://en.openei.org/w/index.php?title=Higher_Power_Energy_LLC&oldid=346535" Categories: Clean Energy Organizations Companies Organizations Stubs What links here

5

Higher Education Energy Loan Program  

Broader source: Energy.gov [DOE]

The Oklahoma Department of Commerce has established a loan/lease fund for institutes of higher education to improve energy efficiency. Two categories of funding are available for schools to reduce...

6

Relativistic Nuclear Energy Density Functionals  

Science Journals Connector (OSTI)

......research-article Articles Relativistic Nuclear Energy Density Functionals Dario Vretenar...196, 2012 137 Relativistic Nuclear Energy Density Functionals Dario Vretenar...and P. Ring 2. Relativistic nuclear energy density functionals Even though......

Dario Vretenar; Tamara Niksic; Peter Ring

2012-10-01T23:59:59.000Z

7

Energy in density gradient  

E-Print Network [OSTI]

Inhomogeneous plasmas and fluids contain energy stored in inhomogeneity and they naturally tend to relax into lower energy states by developing instabilities or by diffusion. But the actual amount of energy in such inhomogeneities has remained unknown. In the present work the amount of energy stored in a density gradient is calculated for several specific density profiles in a cylindric configuration. This is of practical importance for drift wave instability in various plasmas, and in particular in its application in models dealing with the heating of solar corona because the instability is accompanied with stochastic heating, so the energy contained in inhomogeneity is effectively transformed into heat. It is shown that even for a rather moderate increase of the density at the axis in magnetic structures in the corona by a factor 1.5 or 3, the amount of excess energy per unit volume stored in such a density gradient becomes several orders of magnitude greater than the amount of total energy losses per unit ...

Vranjes, J

2015-01-01T23:59:59.000Z

8

High Energy Density Capacitors  

SciTech Connect (OSTI)

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

9

Nuclear energy density optimization  

Science Journals Connector (OSTI)

We carry out state-of-the-art optimization of a nuclear energy density of Skyrme type in the framework of the Hartree-Fock-Bogoliubov theory. The particle-hole and particle-particle channels are optimized simultaneously, and the experimental data set includes both spherical and deformed nuclei. The new model-based, derivative-free optimization algorithm used in this work has been found to be significantly better than standard optimization methods in terms of reliability, speed, accuracy, and precision. The resulting parameter set unedf0 results in good agreement with experimental masses, radii, and deformations and seems to be free of finite-size instabilities. An estimate of the reliability of the obtained parameterization is given, based on standard statistical methods. We discuss new physics insights offered by the advanced covariance analysis.

M. Kortelainen; T. Lesinski; J. Moré; W. Nazarewicz; J. Sarich; N. Schunck; M. V. Stoitsov; S. Wild

2010-08-13T23:59:59.000Z

10

Development of Large Format Lithium Ion Cells with Higher Energy...  

Broader source: Energy.gov (indexed) [DOE]

Hydrogen and Fuel Cells Program Review ES-127 Development of Large Format Lithium Ion Cells with Higher Energy Density Erin O'Driscoll (PI) Han Wu (Presenter) Dow Kokam May 13,...

11

States & Energy Efficiency in Higher Education  

Broader source: Energy.gov [DOE]

This presentation, given through the DOE's Technical Assitance Program (TAP), provides information on States & Energy Efficiency in Higher Education.

12

Energy and Momentum Density in Field Theory  

Science Journals Connector (OSTI)

It is shown that the energy density commutator condition in its simplest form is valid for interacting spin 0, ½, 1 field systems, but not for higher spin fields. The action principle is extended, for this purpose, to arbitrary coordinate frames. There is a discussion of four categories of fields and some explicit consideration of spin 32 as the simplest example that gives additional terms in the energy density commutator. As the fundamental equation of relativistic quantum field theory, the commutator condition makes explicit the greater physical complexity of higher spin fields.

Julian Schwinger

1963-04-15T23:59:59.000Z

13

High Energy Density Ultracapacitors | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation es038smith2011p.pdf More Documents & Publications High Energy Density Ultracapacitors High...

14

High Energy Density Ultracapacitors | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. esp22smith.pdf More Documents & Publications High Energy Density Ultracapacitors High Energy...

15

Alternative Energy for Higher Education  

SciTech Connect (OSTI)

This project provides educational opportunities creating both a teaching facility and center for public outreach. The facility is the largest solar array in Nebraska. It was designed to allow students to experience a variety of technologies and provide the public with opportunities for exposure to the implementation of an alternative energy installation designed for an urban setting. The project integrates products from 5 panel manufacturers (including monocrystalline, polycrystalline and thin film technologies) mounted on both fixed and tracking structures. The facility uses both micro and high power inverters. The majority of the system was constructed to serve as an outdoor classroom where panels can be monitored, tested, removed and replaced by students. As an educational facility it primarily serves students in the Creighton University and Metropolitan Community College, but it also provides broader educational opportunities. The project includes a real-time â??dashboardâ? and a historical database of the output of individual inverters and the corresponding meteorological data for researcher and student use. This allows the evaluation of both panel types and the feasibility of installation types in a region of the country subject to significant temperature, wind and precipitation variation.

Michael Cherney, PhD

2012-02-22T23:59:59.000Z

16

High Energy Density Ultracapacitors | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C. es038smith2010o.pdf More Documents & Publications High Energy Density Ultracapacitors High...

17

Energy density of variational states  

Science Journals Connector (OSTI)

We show, in several important and general cases, that a low variational energy density of a trial state is possible even when the trial state represents a different phase from the ground state. Specifically, we ask whether the ground-state energy density of a Hamiltonian whose ground state is in phase A can be approximated to arbitrary accuracy by a wave function, which represents a different phase B. We show this is indeed the case when A has discrete symmetry breaking order in one dimension or topological order in two dimensions, while B is disordered. We argue that, if reasonable conditions of physicality are imposed upon the trial wave function, then this is not possible when A has discrete symmetry breaking in dimensions greater than one and B is symmetric. Some other situations are also discussed.

Leon Balents

2014-12-08T23:59:59.000Z

18

Development of Large Format Lithium Ion Cells with Higher Energy...  

Broader source: Energy.gov (indexed) [DOE]

Overall Project Goal: To research, develop and demonstrate large format lithium ion cells with energy density > 500 WhL Barriers addressed: - Low energy density - Cost -...

19

Nuclear energy density optimization: Shell structure  

Science Journals Connector (OSTI)

Background: Nuclear density functional theory is the only microscopical theory that can be applied throughout the entire nuclear landscape. Its key ingredient is the energy density functional.

M. Kortelainen; J. McDonnell; W. Nazarewicz; E. Olsen; P.-G. Reinhard; J. Sarich; N. Schunck; S. M. Wild; D. Davesne; J. Erler; A. Pastore

2014-05-15T23:59:59.000Z

20

Recovery Act: Wind Energy Consortia between Institutions of Higher...  

Broader source: Energy.gov (indexed) [DOE]

Recovery Act: Wind Energy Consortia between Institutions of Higher Learning and Industry Recovery Act: Wind Energy Consortia between Institutions of Higher Learning and Industry A...

Note: This page contains sample records for the topic "higher energy 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

Jacek Dobaczewski Density functional theory and energy  

E-Print Network [OSTI]

Jacek Dobaczewski Density functional theory and energy density functionals in nuclear physics Jacek Functional #12;Jacek Dobaczewski Mean-Field Theory Density Functional Theory · mean-field one? Density Functional Theory: A variational method that uses observables as variational parameters. #12;Jacek

Dobaczewski, Jacek

22

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

23

Testing the kinetic energy functional: Kinetic energy density as a density functional  

E-Print Network [OSTI]

is to the exchange-correlation energy as a functional of the density. A large part of the total energy, the kinetic contexts. For finite systems these forms integrate to the same global ki- netic energy, but they differTesting the kinetic energy functional: Kinetic energy density as a density functional Eunji Sim

Burke, Kieron

24

Transport Energy Use and Population Density  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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

25

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

26

Relativistic density functional theory modeling of plutonium and americium higher oxide molecules  

E-Print Network [OSTI]

Relativistic density functional theory modeling of plutonium and americium higher oxide molecules of plutonium and americium higher oxide molecules Andréi Zaitsevskii,1,2,a) Nikolai S. Mosyagin,2,3 Anatoly V of plutonium and americium higher oxide molecules (actinide oxidation states VI through VIII) by two

Titov, Anatoly

27

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

28

Energy per Particle of Neutron Matter near Nuclear Density  

Science Journals Connector (OSTI)

The energy per particle of neutron matter in the density range 1013 to 1015 gcm3 was calculated self-consistently using recent nuclear potentials: the Bressel-Kerman-Rouben potential and the boundary-condition model of Feshbach and Lomon. At low densities the results are in good agreement with other calculations of the energy density of neutron matter. At higher densities, the predicted energy density depends more strongly on the specific potential used. More recent potentials yield somewhat lower pressures for neutron matter (hence a smaller mass range for neutron stars) than those predicted with the Levinger-Simmons potential which has been used as the basis for calculations of neutron-star structure.

Sara L. Schlenker and E. L. Lomon

1971-04-01T23:59:59.000Z

29

Density Estimation Trees in High Energy Physics  

E-Print Network [OSTI]

Density Estimation Trees can play an important role in exploratory data analysis for multidimensional, multi-modal data models of large samples. I briefly discuss the algorithm, a self-optimization technique based on kernel density estimation, and some applications in High Energy Physics.

Anderlini, Lucio

2015-01-01T23:59:59.000Z

30

Universal Nuclear Energy Density Functional  

SciTech Connect (OSTI)

An understanding of the properties of atomic nuclei is crucial for a complete nuclear theory, for element formation, for properties of stars, and for present and future energy and defense applications. During the period of Dec. 1 2006 – Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei, based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. Until recently such an undertaking was hard to imagine, and even at the present time such an ambitious endeavor would be far beyond what a single researcher or a traditional research group could carry out.

Carlson, Joseph; Furnstahl, Richard; Horoi, Mihai; Lusk, Rusty; Nazarewicz, Witold; Ng, Esmond; Thompson, Ian; Vary, James

2012-12-01T23:59:59.000Z

31

Nuclear energy density optimization: Shell structure  

E-Print Network [OSTI]

Nuclear density functional theory is the only microscopical theory that can be applied throughout the entire nuclear landscape. Its key ingredient is the energy density functional. In this work, we propose a new parameterization UNEDF2 of the Skyrme energy density functional. The functional optimization is carried out using the POUNDerS optimization algorithm within the framework of the Skyrme Hartree-Fock-Bogoliubov theory. Compared to the previous parameterization UNEDF1, restrictions on the tensor term of the energy density have been lifted, yielding a very general form of the energy density functional up to second order in derivatives of the one-body density matrix. In order to impose constraints on all the parameters of the functional, selected data on single-particle splittings in spherical doubly-magic nuclei have been included into the experimental dataset. The agreement with both bulk and spectroscopic nuclear properties achieved by the resulting UNEDF2 parameterization is comparable with UNEDF1. While there is a small improvement on single-particle spectra and binding energies of closed shell nuclei, the reproduction of fission barriers and fission isomer excitation energies has degraded. As compared to previous UNEDF parameterizations, the parameter confidence interval for UNEDF2 is narrower. In particular, our results overlap well with those obtained in previous systematic studies of the spin-orbit and tensor terms. UNEDF2 can be viewed as an all-around Skyrme EDF that performs reasonably well for both global nuclear properties and shell structure. However, after adding new data aiming to better constrain the nuclear functional, its quality has improved only marginally. These results suggest that the standard Skyrme energy density has reached its limits and significant changes to the form of the functional are needed.

M. Kortelainen; J. McDonnell; W. Nazarewicz; E. Olsen; P. -G. Reinhard; J. Sarich; N. Schunck; S. M. Wild; D. Davesne; J. Erler; A. Pastore

2013-12-06T23:59:59.000Z

32

Mechanical constraints enhance electrical energy densities of soft dielectrics  

E-Print Network [OSTI]

Mechanical constraints enhance electrical energy densities of soft dielectrics Lin Zhang, Qiming, the dielectric will breakdown electrically. The breakdown limits the electrical energy density of the dielectric electric fields and thus increase their electrical energy densities. The mechanical constraints suppress

Ferrari, Silvia

33

Energy-momentum Density of Gravitational Waves  

E-Print Network [OSTI]

In this paper, we elaborate the problem of energy-momentum in general relativity by energy-momentum prescriptions theory. Our aim is to calculate energy and momentum densities for the general form of gravitational waves. In this connection, we have extended the previous works by using the prescriptions of Bergmann and Tolman. It is shown that they are finite and reasonable. In addition, using Tolman prescription, exactly, leads to same results that have been obtained by Einstein and Papapetrou prescriptions.

Amir M. Abbassi; Saeed Mirshekari

2014-11-29T23:59:59.000Z

34

Energy-Momentum Density of Gravitational Waves  

E-Print Network [OSTI]

In this paper, we elaborate the problem of energy-momentum in general relativity by energy-momentum prescriptions theory. Our aim is to calculate energy and momentum densities for the general form of gravitational waves. In this connection, we have extended the previous works by using the prescriptions of Bergmann and Tolman. It is shown that they are finite and reasonable. In addition, using Tolman prescription, exactly, leads to same results that have been obtained by Einstein and Papapetrou prescriptions.

Amir M. Abbassi; Saeed Mirshekari

2009-08-03T23:59:59.000Z

35

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

36

High-Energy-Density Plasmas, Fluids  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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

37

Novel and Optimized Materials Phases for High Energy Density...  

Broader source: Energy.gov (indexed) [DOE]

Novel and Optimized Materials Phases for High Energy Density Batteries Novel and Optimized Materials Phases for High Energy Density Batteries 2013 DOE Hydrogen and Fuel Cells...

38

TEMPO-based Catholyte for High Energy Density Nonaqueous Redox...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

TEMPO-based Catholyte for High Energy Density Nonaqueous Redox Flow Batteries. TEMPO-based Catholyte for High Energy Density Nonaqueous Redox Flow Batteries. Abstract: We will...

39

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

National Nuclear Security Administration (NNSA)

Photo Gallery Jobs Apply for Our Jobs Our Jobs Working at NNSA Blog Home High Energy Density Laboratory Plasmas Program High Energy Density Laboratory Plasmas Program...

40

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

Note: This page contains sample records for the topic "higher energy 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

Nuclear Energy Density Optimization: UNEDF2  

E-Print Network [OSTI]

The parameters of the UNEDF2 nuclear energy density functional (EDF) model were obtained in an optimization to experimental data consisting of nuclear binding energies, proton radii, odd-even mass staggering data, fission-isomer excitation energies, and single particle energies. In addition to parameter optimization, sensitivity analysis was done to obtain parameter uncertainties and correlations. The resulting UNEDF2 is an all-around EDF. However, the sensitivity analysis also demonstrated that the limits of current Skyrme-like EDFs have been reached and that novel approaches are called for.

Kortelainen, M; Nazarewicz, W; Olsen, E; Reinhard, P -G; Sarich, J; Schunck, N; Wild, S M; Davesne, D; Erler, J; Pastore, A

2014-01-01T23:59:59.000Z

42

Nuclear Energy Density Optimization: UNEDF2  

E-Print Network [OSTI]

The parameters of the UNEDF2 nuclear energy density functional (EDF) model were obtained in an optimization to experimental data consisting of nuclear binding energies, proton radii, odd-even mass staggering data, fission-isomer excitation energies, and single particle energies. In addition to parameter optimization, sensitivity analysis was done to obtain parameter uncertainties and correlations. The resulting UNEDF2 is an all-around EDF. However, the sensitivity analysis also demonstrated that the limits of current Skyrme-like EDFs have been reached and that novel approaches are called for.

M. Kortelainen; J. McDonnell; W. Nazarewicz; E. Olsen; P. -G. Reinhard; J. Sarich; N. Schunck; S. M. Wild; D. Davesne; J. Erler; A. Pastore

2014-10-30T23:59:59.000Z

43

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

44

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

SciTech Connect (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

45

Energy-Density Relation for Nuclear Matter  

Science Journals Connector (OSTI)

In most previous calculations of nuclear matter the energy has been calculated only at the equilibrium density, which density has been determined by a minimum condition. In the present paper the author's theory of nuclear matter is applied to a study of the complete energy-density relation of nuclear matter, in the neighborhood of the equilibrium density. The emphasis here is not upon duplicating the accepted value for the equilibrium binding energy, but rather upon a study of the leading (diagonal) contribution of the quasi-particle interaction term g1(k1k2|k3k4), which is the matrix element of a reaction matrix G1. It is shown that g1(k1k2|k1k2) must be evaluated partly by using observed nucleon-nucleon scattering phase shifts and partly by calculating the close-in behavior of the two-nucleon wave function, and that this second part receives a large contribution from the deuteron state. Curves are given for the dependence of g1(k1k2|k1k2) on the density and the center-of-mass momentum. It is also shown that g1(k1k2|k1k2) is sensitive to the size of the nucleon repulsive core, but not upon the character of the attraction, when agreement with scattering data has first been achieved. Finally, a comparison of g1(k1k2|k1k2) with the prediction of first-order perturbation theory is made.

Franz Mohling

1962-11-01T23:59:59.000Z

46

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

47

Innovative High Energy Density Capacitor Design Offers Potential...  

Broader source: Energy.gov (indexed) [DOE]

like TroyCap's High Density Energy Nanolaminate Capacitor (HEDCAP) that may offer new clean energy applications to meet the nation's strategic energy goals and secure...

48

Density content of nuclear symmetry energy from nuclear observables  

Science Journals Connector (OSTI)

The nuclear symmetry energy at a given density measures the energy transferred in converting symmetric nuclear matter into the pure neutron matter. The density content of nuclear symmetry energy remains poorly co...

B K AGRAWAL

2014-11-01T23:59:59.000Z

49

ORBITAL-FREE KINETIC-ENERGY DENSITY FUNCTIONAL THEORY  

E-Print Network [OSTI]

Chapter 5 ORBITAL-FREE KINETIC-ENERGY DENSITY FUNCTIONAL THEORY Yan Alexander Wang and Emily A Theory (DFT), there was the Thomas-Fermi (TF) model, which uses the electron density ¢¡ r£ (a function-dependent DFT Density-Functional Theory DI density-independent DM1 first-order reduced density matrix EDF energy

Wang, Yan Alexander

50

High energy density redox flow device  

DOE Patents [OSTI]

Redox flow devices are described in which at least one of the positive electrode or negative electrode-active materials is a semi-solid or is a condensed ion-storing electroactive material, and in which at least one of the electrode-active materials is transported to and from an assembly at which the electrochemical reaction occurs, producing electrical energy. The electronic conductivity of the semi-solid is increased by the addition of conductive particles to suspensions and/or via the surface modification of the solid in semi-solids (e.g., by coating the solid with a more electron conductive coating material to increase the power of the device). High energy density and high power redox flow devices are disclosed. The redox flow devices described herein can also include one or more inventive design features. In addition, inventive chemistries for use in redox flow devices are also described.

Chiang, Yet-Ming; Carter, W. Craig; Ho, Bryan Y; Duduta, Mihai; Limthongkul, Pimpa

2014-05-13T23:59:59.000Z

51

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...

52

SURFACE SYMMETRY ENERGY OF NUCLEAR ENERGY DENSITY FUNCTIONALS  

SciTech Connect (OSTI)

We study the bulk deformation properties of the Skyrme nuclear energy density functionals. Following simple arguments based on the leptodermous expansion and liquid drop model, we apply the nuclear density functional theory to assess the role of the surface symmetry energy in nuclei. To this end, we validate the commonly used functional parametrizations against the data on excitation energies of superdeformed band-heads in Hg and Pb isotopes, and fission isomers in actinide nuclei. After subtracting shell effects, the results of our self-consistent calculations are consistent with macroscopic arguments and indicate that experimental data on strongly deformed configurations in neutron-rich nuclei are essential for optimizing future nuclear energy density functionals. The resulting survey provides a useful benchmark for further theoretical improvements. Unlike in nuclei close to the stability valley, whose macroscopic deformability hangs on the balance of surface and Coulomb terms, the deformability of neutron-rich nuclei strongly depends on the surface-symmetry energy; hence, its proper determination is crucial for the stability of deformed phases of the neutron-rich matter and description of fission rates for r-process nucleosynthesis.

Nikolov, N; Schunck, N; Nazarewicz, W; Bender, M; Pei, J

2010-12-20T23:59:59.000Z

53

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

54

Higher-order adaptive finite-element methods for Kohn–Sham density functional theory  

SciTech Connect (OSTI)

We present an efficient computational approach to perform real-space electronic structure calculations using an adaptive higher-order finite-element discretization of Kohn–Sham density-functional theory (DFT). To this end, we develop an a priori mesh-adaption technique to construct a close to optimal finite-element discretization of the problem. We further propose an efficient solution strategy for solving the discrete eigenvalue problem by using spectral finite-elements in conjunction with Gauss–Lobatto quadrature, and a Chebyshev acceleration technique for computing the occupied eigenspace. The proposed approach has been observed to provide a staggering 100–200-fold computational advantage over the solution of a generalized eigenvalue problem. Using the proposed solution procedure, we investigate the computational efficiency afforded by higher-order finite-element discretizations of the Kohn–Sham DFT problem. Our studies suggest that staggering computational savings—of the order of 1000-fold—relative to linear finite-elements can be realized, for both all-electron and local pseudopotential calculations, by using higher-order finite-element discretizations. On all the benchmark systems studied, we observe diminishing returns in computational savings beyond the sixth-order for accuracies commensurate with chemical accuracy, suggesting that the hexic spectral-element may be an optimal choice for the finite-element discretization of the Kohn–Sham DFT problem. A comparative study of the computational efficiency of the proposed higher-order finite-element discretizations suggests that the performance of finite-element basis is competing with the plane-wave discretization for non-periodic local pseudopotential calculations, and compares to the Gaussian basis for all-electron calculations to within an order of magnitude. Further, we demonstrate the capability of the proposed approach to compute the electronic structure of a metallic system containing 1688 atoms using modest computational resources, and good scalability of the present implementation up to 192 processors.

Motamarri, P. [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Nowak, M.R. [Department of Electrical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)] [Department of Electrical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Leiter, K.; Knap, J. [U.S. Army Research Labs, Aberdeen Proving Ground, Aberdeen, MD 21001 (United States)] [U.S. Army Research Labs, Aberdeen Proving Ground, Aberdeen, MD 21001 (United States); Gavini, V., E-mail: vikramg@umich.edu [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

2013-11-15T23:59:59.000Z

55

Energy density fluctuations in early universe  

SciTech Connect (OSTI)

The primordial nucleosinthesys of the element can be influenced by the transitions of phase that take place after the Big Bang, such as the QCD transition. In order to study the effect of this phase transition, in this work we compute the time evolution of thermodynamical quantities of the early universe, focusing on temperature and energy density fluctuations, by solving the relevant equations of motion using as input the lattice QCD equation of state to describe the strongly interacting matter in the early universe plasma. We also study the effect of a primordial strong magnetic field by means of a phenomenological equation of state. Our results show that small inhomogeneities of strongly interacting matter in the early Universe are moderately damped during the crossover.

Guardo, G. L.; Ruggieri, M. [Department of Physics and Astronomy, University of Catania, Catania (Italy); Greco, V. [Department of Physics and Astronomy, University of Catania, Catania, Italy and INFN - Laboratori Nazionali del Sud, Catania (Italy)

2014-05-09T23:59:59.000Z

56

Energy density fluctuations in Early Universe  

E-Print Network [OSTI]

The primordial nucleosinthesys of the element can be influenced by the transitions of phase that take place after the Big Bang, such as the QCD transition. In order to study the effect of this phase transition, in this work we compute the time evolution of thermodynamical quantities of the early universe, focusing on temperature and energy density fluctuations, by solving the relevant equations of motion using as input the lattice QCD equation of state to describe the strongly interacting matter in the early universe plasma. We also study the effect of a primordial strong magnetic field by means of a phenomenological equation of state. Our results show that small inhomogeneities of strongly interacting matter in the early Universe are moderately damped during the crossover.

Guardo, G L; Ruggieri, M

2014-01-01T23:59:59.000Z

57

HIGHLY COMPRESSED ION BEAMS FOR HIGH ENERGY DENSITY SCIENCE  

E-Print Network [OSTI]

HIGHLY COMPRESSED ION BEAMS FOR HIGH ENERGY DENSITY SCIENCE A. Friedman1,2 , J.J.Barnard1,2 , R Energy Density regimes required for Inertial Fu- sion Energy and other applications. An interim goal we are pursuing, low to medium mass ions with energies just above the Bragg peak are directed onto

Wurtele, Jonathan

58

Nuclear symmetry energy at subnormal densities from measured nuclear masses  

Science Journals Connector (OSTI)

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

Min Liu; Ning Wang; Zhu-Xia Li; Feng-Shou Zhang

2010-12-13T23:59:59.000Z

59

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

60

Design implications and potentials of passive solar heating in higher density communities: the Lykovrissi Solar Village  

SciTech Connect (OSTI)

Carefully analyzed building density, massing, and orientation become critical if solar access to the building is to be maintained. Even more carefully thought out building organization and room planning is critical if solar access to the apartment is to be maintained. Finally, careful material and component selection and placement, as well as window control system design is critical if solar access (heating) for the individual is to be maintained. The prerequisite guidelines necessary to ensure this completed solar access were established for the design of the Lykovrissi Solar Village now under construction near Athens. Fulfilling a cooperative agreement of 1978 between Germany and Greece, a community of rowhouses and three-to-six story multi-family units have been designed to provide energy efficient and solar assisted housing for 431 low income families, with a clear perspective on comparing solar systems for future subsidized housing.

Loftness, V. (INTERATOM, Bergisch Gladbach, Germany); Boese, F.K.; Tombazis, A.; Mouzakis, J.

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Development of nuclear models for higher energy calculations  

SciTech Connect (OSTI)

Two nuclear models for higher energy calculations have been developed in the regions of high and low energy transfer, respectively. In the former, a relativistic hybrid-type preequilibrium model is compared with data ranging from 60 to 800 MeV. Also, the GNASH exciton preequilibrium-model code with higher energy improvements is compared with data at 200 and 318 MeV. In the region of low energy transfer, nucleon-nucleus scattering is predominately a direct reaction involving quasi-elastic collisions with one or more target nucleons. We discuss various aspects of quasi-elastic scattering which are important in understanding features of cross sections and spin observables. These include (1) contributions from multi-step processes; (2) damping of the continuum response from 2p-2h excitations; (3) the ''optimal'' choice of frame in which to evaluate the nucleon-nucleon amplitudes; and (4) the effect of optical and spin-orbit distortions, which are included in a model based on the RPA the DWIA and the eikonal approximation. 33 refs., 15 figs.

Bozoian, M.; Siciliano, E.R.; Smith, R.D.

1988-01-01T23:59:59.000Z

62

Innovative High Energy Density Capacitor Design Offers Potential for Clean  

Broader source: Energy.gov (indexed) [DOE]

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,

63

Innovative High Energy Density Capacitor Design Offers Potential for Clean  

Broader source: Energy.gov (indexed) [DOE]

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

64

The Impact of Residential Density on Vehicle Usage and Energy Consumption  

E-Print Network [OSTI]

Residential Density on Vehicle Usage and Energy ConsumptionResidential Density on Vehicle Usage and Energy ConsumptionResidential Density on Vehicle Usage and Energy Consumption

Golob, Thomas F; Brownstone, David

2005-01-01T23:59:59.000Z

65

Building a Universal Nuclear Energy Density Functional  

SciTech Connect (OSTI)

During the period of Dec. 1 2006 – Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei, based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. The long-term vision initiated with UNEDF is to arrive at a comprehensive, quantitative, and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. We seek to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties. Specifically, the mission of this project has been three-fold: ? First, to find an optimal energy density functional (EDF) using all our knowledge of the nucleonic Hamiltonian and basic nuclear properties; ? Second, to apply the EDF theory and its extensions to validate the functional using all the available relevant nuclear structure and reaction data; ? Third, to apply the validated theory to properties of interest that cannot be measured, in particular the properties needed for reaction theory.

Carlson, Joe A. [Michigan State University; Furnstahl, Dick; Horoi, Mihai; Lust, Rusty; Nazaewicc, Witek; Ng, Esmond; Thompson, Ian; Vary, James

2012-12-30T23:59:59.000Z

66

Unambiguous exchange-correlation energy density Kieron Burke,a)  

E-Print Network [OSTI]

density approximation LDA , the conventional form is eXC unif (r) , the exchange-correlation energy the following definition of an energy density: eXC wave fn. r d3 r P r,r r r 2 r r 1 2 2 r,r s r,r r r , 2 whereUnambiguous exchange-correlation energy density Kieron Burke,a) Federico G. Cruz, and Kin-Chung Lam

Burke, Kieron

67

Congruent energy density trends of fish and birds reflect ecosystem ...  

Science Journals Connector (OSTI)

We used long-term biomonitoring data to calculate whole-body energy densities for Lake Huron rainbow smelt (Osmerus mordax), lake trout (Salvelinus ...

68

Superior Long-Term Energy Retention and Volumetric Energy Density for Li-Rich Cathode Materials  

Science Journals Connector (OSTI)

Superior Long-Term Energy Retention and Volumetric Energy Density for Li-Rich Cathode Materials ... †Department of Energy Engineering, School of

Pilgun Oh; Seungjun Myeong; Woongrae Cho; Min-Joon Lee; Minseong Ko; Hu Young Jeong; Jaephil Cho

2014-09-02T23:59:59.000Z

69

THE MANY-ELECTRON ENERGY IN DENSITY FUNCTIONAL THEORY  

E-Print Network [OSTI]

THE MANY-ELECTRON ENERGY IN DENSITY FUNCTIONAL THEORY From Exchange-Correlation Functional Design to the configuration of its electrons. Computer programs based on density functional theory (DFT) can calculate applicable within the field of computational density functional theory. Sammanfattning Att förutsäga

Armiento, Rickard

70

Symmetry Energy as a Function of Density and Mass  

E-Print Network [OSTI]

Energy in nuclear matter is, in practice, completely characterized at different densities and asymmetries, when the density dependencies of symmetry energy and of energy of symmetric matter are specified. The density dependence of the symmetry energy at subnormal densities produces mass dependence of nuclear symmetry coefficient and, thus, can be constrained by that latter dependence. We deduce values of the mass dependent symmetry coefficients, by using excitation energies to isobaric analog states. The coefficient systematic, for intermediate and high masses, is well described in terms of the symmetry coefficient values of a_a^V=(31.5-33.5) MeV for the volume coefficient and a_a^S=(9-12) MeV for the surface coefficient. These two further correspond to the parameter values describing density dependence of symmetry energy, of L~95 MeV and K_{sym}~25 MeV.

Pawel Danielewicz; Jenny Lee

2007-08-21T23:59:59.000Z

71

Symmetry Energy as a Function of Density and Mass  

SciTech Connect (OSTI)

Energy in nuclear matter is, in practice, completely characterized at different densities and asymmetries, when the density dependencies of symmetry energy and of energy of symmetric matter are specified. The density dependence of the symmetry energy at subnormal densities produces mass dependence of nuclear symmetry coefficient and, thus, can be constrained by that latter dependence. We deduce values of the mass dependent symmetry coefficients, by using excitation energies to isobaric analog states. The coefficient systematic, for intermediate and high masses, is well described in terms of the symmetry coefficient values of a{sub a}{sup V} = (31.5-33.5) MeV for the volume coefficient and a{sub a}{sup S} = (9-12) MeV for the surface coefficient. These two further correspond to the parameter values describing density dependence of symmetry energy, of L{approx}95 MeV and K{sub sym}{approx}25 MeV.

Danielewicz, Pawel; Lee, Jenny [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)

2007-10-26T23:59:59.000Z

72

Symmetry Energy as a Function of Density and Mass  

E-Print Network [OSTI]

Energy in nuclear matter is, in practice, completely characterized at different densities and asymmetries, when the density dependencies of symmetry energy and of energy of symmetric matter are specified. The density dependence of the symmetry energy at subnormal densities produces mass dependence of nuclear symmetry coefficient and, thus, can be constrained by that latter dependence. We deduce values of the mass dependent symmetry coefficients, by using excitation energies to isobaric analog states. The coefficient systematic, for intermediate and high masses, is well described in terms of the symmetry coefficient values of a_a^V=(31.5-33.5) MeV for the volume coefficient and a_a^S=(9-12) MeV for the surface coefficient. These two further correspond to the parameter values describing density dependence of symmetry energy, of L~95 MeV and K_{sym}~25 MeV.

Danielewicz, Pawel

2007-01-01T23:59:59.000Z

73

Concrete Company Aims Higher for More Wind Energy | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy July 29, 2010 - 6:41pm Addthis The EnergySmart Jobs program is a three-pronged approach to creating “green jobs” for Californians while also increasing energy efficiency at businesses around the state. | File photo The EnergySmart Jobs program is a three-pronged approach to creating "green jobs" for Californians while also increasing energy efficiency at businesses around the state. | File photo Stephen Graff Former Writer & editor for Energy Empowers, EERE What does this mean for me? Tindall Corporation received $16.7 million in 48C tax credits to build new plant Kansas facility will manufacture concrete wind tower bases over 100 meters in height

74

Concrete Company Aims Higher for More Wind Energy | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy Concrete Company Aims Higher for More Wind Energy July 29, 2010 - 6:41pm Addthis The EnergySmart Jobs program is a three-pronged approach to creating “green jobs” for Californians while also increasing energy efficiency at businesses around the state. | File photo The EnergySmart Jobs program is a three-pronged approach to creating "green jobs" for Californians while also increasing energy efficiency at businesses around the state. | File photo Stephen Graff Former Writer & editor for Energy Empowers, EERE What does this mean for me? Tindall Corporation received $16.7 million in 48C tax credits to build new plant Kansas facility will manufacture concrete wind tower bases over 100 meters in height

75

Covariance analysis for Energy Density Functionals and instabilities  

E-Print Network [OSTI]

We present the covariance analysis of two successful nuclear energy density functionals, (i) a non-relativistic Skyrme functional built from a zero-range effective interaction, and (ii) a relativistic nuclear energy density functional based on density dependent meson-nucleon couplings. Such a study is crucial for assessing the information content of an observable when predicted by a given model. The covariance analysis is a useful tool for understanding the limitations of a model, the correlations between observables and the statistical errors. We also provide a brief review, partly connected with the covariance analysis, of some instabilities displayed by several energy density functionals of current use in nuclear physics.

Roca-Maza, X; Colò, G

2014-01-01T23:59:59.000Z

76

Constraints on the density dependence of the symmetry energy  

E-Print Network [OSTI]

Collisions involving 112Sn and 124Sn nuclei have been simulated with the improved Quantum Molecular Dynamics transport model. The results of the calculations reproduce isospin diffusion data from two different observables and the ratios of neutron and proton spectra. By comparing these data to calculations performed over a range of symmetry energies at saturation density and different representations of the density dependence of the symmetry energy, constraints on the density dependence of the symmetry energy at sub-normal density are obtained. Results from present work are compared to constraints put forward in other recent analysis.

M. B. Tsang; Yingxun Zhang; P. Danielewicz; M. Famiano; Zhuxia Li; W. G. Lynch; A. W. Steiner

2008-11-19T23:59:59.000Z

77

Constraints on the Density Dependence of the Symmetry Energy  

SciTech Connect (OSTI)

Collisions involving {sup 112}Sn and {sup 124}Sn nuclei have been simulated with the improved quantum molecular dynamics transport model. The results of the calculations reproduce isospin diffusion data from two different observables and the ratios of neutron and proton spectra. By comparing these data to calculations performed over a range of symmetry energies at saturation density and different representations of the density dependence of the symmetry energy, constraints on the density dependence of the symmetry energy at subnormal density are obtained. The results from the present work are compared to constraints put forward in other recent analyses.

Tsang, M. B.; Danielewicz, P.; Lynch, W. G.; Steiner, A. W. [Joint Institute of Nuclear Astrophysics and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Physics and Astronomy Department, Michigan State University, East Lansing, Michigan 48824 (United States); Zhang Yingxun [Joint Institute of Nuclear Astrophysics and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China); Famiano, M. [Physics Department, Western Michigan University, Kalamazoo, Michigan 49008 (United States); Li, Zhuxia [China Institute of Atomic Energy, P.O. Box 275 (18), Beijing 102413 (China)

2009-03-27T23:59:59.000Z

78

Constraints on the density dependence of the symmetry energy  

E-Print Network [OSTI]

Collisions involving 112Sn and 124Sn nuclei have been simulated with the improved Quantum Molecular Dynamics transport model. The results of the calculations reproduce isospin diffusion data from two different observables and the ratios of neutron and proton spectra. By comparing these data to calculations performed over a range of symmetry energies at saturation density and different representations of the density dependence of the symmetry energy, constraints on the density dependence of the symmetry energy at sub-normal density are obtained. Results from present work are compared to constraints put forward in other recent analysis.

Tsang, M B; Danielewicz, P; Famiano, M; Li, Zhuxia; Lynch, W G; Steiner, A W

2008-01-01T23:59:59.000Z

79

Symmetry energy at subnuclear densities deduced from nuclear masses  

E-Print Network [OSTI]

We examine how nuclear masses are related to the density dependence of the symmetry energy. Using a macroscopic nuclear model we calculate nuclear masses in a way dependent on the equation of state of asymmetric nuclear matter. We find by comparison with empirical two-proton separation energies that a smaller symmetry energy at subnuclear densities, corresponding to a larger density symmetry coefficient L, is favored. This tendency, which is clearly seen for nuclei that are neutron-rich, nondeformed, and light, can be understood from the property of the surface symmetry energy in a compressible liquid-drop picture.

Kazuhiro Oyamatsu; Kei Iida

2010-04-19T23:59:59.000Z

80

ESS 2012 Peer Review - Novel High Energy Density Dielectrics...  

Broader source: Energy.gov (indexed) [DOE]

National Laboratories 2012 DOE ESS Peer Review Temperature Energy Response Time Cost New BZT-BT Ceramics Improve upon strengths of ceramics (ripple, temperature) with higher...

Note: This page contains sample records for the topic "higher energy 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

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

82

Energy Consumption and Energy Density in Optical and Electronic Signal Processing  

E-Print Network [OSTI]

Energy Consumption and Energy Density in Optical and Electronic Signal Processing Volume 3, Number-0655/$26.00 ©2011 IEEE #12;Energy Consumption and Energy Density in Optical and Electronic Signal Processing Rodney optical and digital electronic signal processing circuits, including the contributions to energy

Tucker, Rod

83

Relativistic plasma nanophotonics for ultrahigh energy density physics  

E-Print Network [OSTI]

Relativistic plasma nanophotonics for ultrahigh energy density physics Michael A. Purvis1 volumetrically heat dense matter into a new ultrahot plasma regime. Electron densities nearly 100 times greater) and gigabar press- ures only exceeded in the central hot spot of highly compressed thermonuclear fusion

Rocca, Jorge J.

84

Probing the density content of the nuclear symmetry energy  

Science Journals Connector (OSTI)

In this paper, we shall mainly focus on the behaviour of symmetry energy slope parameter L at densities close to ? 0. The value of L(? 0) has been shown [5] to be strongly correlat...

B K AGRAWAL; J N DE; S K SAMADDAR

2014-05-01T23:59:59.000Z

85

Does Cosmological Vacuum Energy Density have an Electric Reason ?  

E-Print Network [OSTI]

Rather uncomplicated calculations by hand display a surprising connection between the energy density of the vacuum and the diameter and age of the universe. Among other things, the result explains the observation of the accelerated expansion of the universe.

Claus W. Turtur

2004-03-11T23:59:59.000Z

86

High energy density physics generated by intense heavy ion beams  

Science Journals Connector (OSTI)

Intense ion beams from accelerators are now available to generate high energy density matter and to study astrophysical phenomena in the laboratory under controlled and reproducible conditions. A detailed unde...

D. H. H. Hoffmann; V. E. Fortov; M. Kuster; V. Mintsev…

2009-08-01T23:59:59.000Z

87

High Energy Density Science with High Peak Power Light Sources  

Science Journals Connector (OSTI)

High energy density (HED) science is a growing sub-field of plasma and condensed matter physics. I will examine how recent technological developments in high peak power, petawatt-class...

Ditmire, Todd

88

Molecular Binding Energies from Partition Density Functional Theory  

SciTech Connect (OSTI)

Approximate molecular calculations via standard Kohn-Sham density functional theory are exactly reproduced by performing self-consistent calculations on isolated fragments via partition density functional theory [P. Elliott, K. Burke, M. H. Cohen, and A. Wasserman, Phys. Rev. A 82, 024501 (2010)]. We illustrate this with the binding curves of small diatomic molecules. We find that partition energies are in all cases qualitatively similar and numerically close to actual binding energies. We discuss qualitative features of the associated partition potentials.

Nafziger, J.; Wu, Q.; Wasserman, A.

2011-12-21T23:59:59.000Z

89

Conformal Higgs model: predicted dark energy density  

E-Print Network [OSTI]

Postulated universal Weyl conformal scaling symmetry provides an alternative to the $\\Lambda$CDM paradigm for cosmology. Recent applications to galactic rotation velocities, Hubble expansion, and a model of dark galactic halos explain qualitative phenomena and fit observed data without invoking dark matter. Significant revision of theory relevant to galactic collisions and clusters is implied, but not yet tested. Dark energy is found to be a consequence of conformal symmetry for the Higgs scalar field of electroweak physics. The present paper tests this implication. The conformal Higgs model acquires a gravitational effect described by a modified Friedmann cosmic evolution equation, shown to fit cosmological data going back to the cosmic microwave background epoch. The tachyonic mass parameter of the Higgs model becomes dark energy in the Friedmann equation. A dynamical model of this parameter, analogous to the Higgs mechanism for gauge boson mass, is derived and tested here. An approximate calculation yields a result consistent with the empirical magnitude inferred from Hubble expansion.

R. K. Nesbet

2014-11-03T23:59:59.000Z

90

Energy Density Inhomogeneities with Polynomial $f(R)$ Cosmology  

E-Print Network [OSTI]

In this paper, we study the effects of polynomial $f(R)$ model on the stability of homogeneous energy density in self-gravitating spherical stellar object. For this purpose, we construct couple of evolution equations which relate the Weyl tensor with matter parameters. We explore different factors responsible for density inhomogeneities with non-dissipative dust, isotropic as well as anisotropic fluids and dissipative dust cloud. We find that shear, pressure, dissipative parameters and $f(R)$ terms affect the existence of inhomogeneous energy density.

Sharif, M

2015-01-01T23:59:59.000Z

91

High Energy Density Laboratory Plasmas Program | National Nuclear Security  

National Nuclear Security Administration (NNSA)

Program | National Nuclear Security Program | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery 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 Program High Energy Density Laboratory Plasmas Program Steady advances in increasing the energy, power, and brightness of lasers and particle beams and advances in pulsed power systems have made possible

92

Energy Department Announces Funding to Access Higher Quality...  

Office of Environmental Management (EM)

turbulent - limiting the amount of electricity generated from wind energy. Taller wind turbines take advantage of the stronger, more consistent winds available at greater heights...

93

Energy Density Functional for Nuclei and Neutron Stars  

SciTech Connect (OSTI)

Background: Recent observational data on neutron star masses and radii provide stringent constraints on the equation of state of neutron rich matter [ Annu. Rev. Nucl. Part. Sci. 62 485 (2012)]. Purpose: We aim to develop a nuclear energy density functional that can be simultaneously applied to finite nuclei and neutron stars. Methods: We use the self-consistent nuclear density functional theory (DFT) with Skyrme energy density functionals and covariance analysis to assess correlations between observables for finite nuclei and neutron stars. In a first step two energy functionals a high density energy functional giving reasonable neutron properties, and a low density functional fitted to nuclear properties are matched. In a second step, we optimize a new functional using exactly the same protocol as in earlier studies pertaining to nuclei but now including neutron star data. This allows direct comparisons of performance of the new functional relative to the standard one. Results: The new functional TOV-min yields results for nuclear bulk properties (energy, rms radius, diffraction radius, and surface thickness) that are of the same quality as those obtained with the established Skyrme functionals, including SV-min. When comparing SV-min and TOV-min, isoscalar nuclear matter indicators vary slightly while isovector properties are changed considerably. We discuss neutron skins, dipole polarizability, separation energies of the heaviest elements, and proton and neutron drip lines. We confirm a correlation between the neutron skin of 208Pb and the neutron star radius. Conclusions: We demonstrate that standard energy density functionals optimized to nuclear data do not carry information on the expected maximum neutron star mass, and that predictions can only be made within an extremely broad uncertainty band. For atomic nuclei, the new functional TOV-min performs at least as well as the standard nuclear functionals, but it also reproduces expected neutron star data within assumed error bands. This functional is expected to yield more reliable predictions in the region of very neutron rich heavy nuclei.

Erler, J. [UTK/ORNL/German Cancer Research Center-Heidelberg; Horowitz, C. J. [UTK/ORNL/Indiana University; Nazarewicz, Witold [UTK/ORNL/University of Warsaw; Rafalski, M. [UTK/ORNL; Reinhard, P.-G. [Universitat Erlangen, Germany

2013-01-01T23:59:59.000Z

94

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

95

Vacuum Casimir energy densities and field divergences at boundaries  

E-Print Network [OSTI]

We consider and review the emergence of singular energy densities and field fluctuations at sharp boundaries or point-like field sources in the vacuum. The presence of singular energy densities of a field may be relevant from a conceptual point of view, because they contribute to the self-energy of the system. They should also generate significant gravitational effects. We first consider the case of the interface between a metallic boundary and the vacuum, and obtain the structure of the singular electric and magnetic energy densities at the interface through an appropriate limit from a dielectric to an ideal conductor. Then, we consider the case of a point-like source of the electromagnetic field, and show that also in this case the electric and magnetic energy densities show a singular structure at the source position. We discuss how, in both cases, these singularities give an essential contribution to the electromagnetic self-energy of the system; moreover, they solve an apparent inconsistency between the ...

Bartolo, Nicola; Lattuca, Margherita; Passante, Roberto; Rizzuto, Lucia; Spagnolo, Salvatore

2014-01-01T23:59:59.000Z

96

Superheavy hidden sectors and the vacuum energy density  

E-Print Network [OSTI]

In the present work a quintessence like mechanism is presented, which models a considerable fraction of the critical energy density today $\\rho_c\\simeq 10^{-47}\\;\\hbox{GeV}^4$. By assuming that the Quantum Field Theory vacuum energy is lowered down to zero by a suitable adjustment mechanism, the critical energy density is modelled in terms of a quintessence axion field $a$. This axion is a pseudo-Goldstone boson arising due to a symmetry breaking mechanism in a hidden sector, corresponding to an $\\hbox{SU(2)}$ gauge interaction. The unification between the latter sector and QCD is produced at a very large energy scale, of the order of the GUT or even of the Planck energy. This theory is confining at a very low scale, of the order of a very light neutrino mass $m_\

Santillán, Osvaldo P

2015-01-01T23:59:59.000Z

97

The Impact of Residential Density on Vehicle Usage and Energy Consumption  

E-Print Network [OSTI]

Residential Density on Vehicle Usage and Energy ConsumptionType Choice, and Fuel Usage Total annual residentialResidential Density on Vehicle Usage and Energy Consumption

Golob, Thomas F.; Brownstone, David

2005-01-01T23:59:59.000Z

98

Radiating Gravitational Collapse with an Initial Inhomogeneous Energy Density Distribution  

E-Print Network [OSTI]

A new model is proposed to a collapsing star consisting of an initial inhomogeneous energy density and anisotropic pressure fluid with shear, radial heat flow and outgoing radiation. In previous papers one of us has always assumed an initial star with homogeneous energy density. The aim of this work is to generalize the previous models by introducing an initial inhomogeneous energy density and compare it to the initial homogeneous energy density collapse model. We will show the differences between these models in the evolution of all physical quantities that characterizes the gravitational collapse. The behavior of the energy density, pressure, mass, luminosity and the effective adiabatic index is analyzed. The pressure of the star, at the beginning of the collapse, is isotropic but due to the presence of the shear the pressure becomes more and more anisotropic. The black hole is never formed because the apparent horizon formation condition is never satisfied, in contrast of the previous model where a black hole is formed. An observer at infinity sees a radial point source radiating exponentially until reaches the time of maximum luminosity and suddenly the star turns off. In contrast of the former model where the luminosity also increases exponentially, reaching a maximum and after it decreases until the formation of the black hole. The effective adiabatic index is always positive without any discontinuity in contrast of the former model where there is a discontinuity around the time of maximum luminosity. The collapse is about three thousand times slower than in the case where the energy density is initially homogeneous.

G. Pinheiro; R. Chan

2014-06-01T23:59:59.000Z

99

High Energy Density Laboratory Plasmas | National Nuclear Security  

National Nuclear Security Administration (NNSA)

| National Nuclear Security | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog HEDLP High Energy Density Laboratory Plasmas Home > About Us > Our Programs > Defense Programs > Office of Research, Development, Test, and Evaluation > University Partnerships / Academic Alliances > High Energy Density Laboratory Plasmas

100

Probing the density dependence of symmetry energy at subsaturation density with HICs  

E-Print Network [OSTI]

The reaction mechanism of the central collisions and peripheral collisions for $^{112,124}Sn+^{112,124}Sn$ at $E/A=50MeV$ is investigated within the framework of the Improved Quantum Molecular Dynamics model. The results show that multifragmentation process is an important mechanism at this energy region, and the influence of the cluster emission on the double n/p ratios and the isospin transport ratio are important. Furthermore, three observables, double n/p ratios, isospin diffusion and the rapidity distribution of the ratio $R_{7}$ for $^{112,124}Sn+^{112,124}Sn$ at E/A=50MeV are analyzed with the Improved Quantum Molecular Dynamics model. The results show that these three observables are sensitive to the density dependence of the symmetry energy. By comparing the calculation results to the data, the consistent constraint on the density dependence of the symmetry energy from these three observables is obtained.

Zhang, Yingxun; Li, Zhuxia; Danielewicz, P; Lynch, W G; Lu, Xiaohua

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Probing the density dependence of symmetry energy at subsaturation density with HICs  

E-Print Network [OSTI]

The reaction mechanism of the central collisions and peripheral collisions for $^{112,124}Sn+^{112,124}Sn$ at $E/A=50MeV$ is investigated within the framework of the Improved Quantum Molecular Dynamics model. The results show that multifragmentation process is an important mechanism at this energy region, and the influence of the cluster emission on the double n/p ratios and the isospin transport ratio are important. Furthermore, three observables, double n/p ratios, isospin diffusion and the rapidity distribution of the ratio $R_{7}$ for $^{112,124}Sn+^{112,124}Sn$ at E/A=50MeV are analyzed with the Improved Quantum Molecular Dynamics model. The results show that these three observables are sensitive to the density dependence of the symmetry energy. By comparing the calculation results to the data, the consistent constraint on the density dependence of the symmetry energy from these three observables is obtained.

Yingxun Zhang; M. B. Tsang; Zhuxia Li; P. Danielewicz; W. G. Lynch; Xiaohua Lu

2009-11-09T23:59:59.000Z

102

Determination of the nuclear level density at high excitation energy  

Science Journals Connector (OSTI)

Evaporation simulations are presented to illustrate the problems associated with the determination of the nuclear level density constant at high excitation energy from evaporation spectra. The methods of using either the total (whole chain) spectra or the difference (from two different initial excitation energies) spectra are discussed. Data from the study of the reaction 701 MeV Si28+100Mo are presented and both methods are used to extract the level density constant. We find that in order to reproduce the slopes of the light particle spectra the level density constant must have a value near 1/10A– 1) / 11 A for excited nuclei with statistical temperatures in the range of 3.5 to 5.5 MeV. This presumes that the only parameter adjustment required to treat the decay of highly exited nuclei is the level density constant. If this is so, the shapes of the evaporation spectra imply a reduction in the level density constant from the value required to explain the decay of less highly excited nuclei, a conclusion reached by others. However, the reduced level density constant leads to an overproduction of deuterons and tritons. This suggests that a more complicated set of parameter adjustments may be required to treat the decay of highly excited nuclei.

A. Chbihi; L. G. Sobotka; N. G. Nicolis; D. G. Sarantites; D. W. Stracener; Z. Majka; D. C. Hensley; J. R. Beene; M. L. Halbert

1991-02-01T23:59:59.000Z

103

Role of density dependent symmetry energy in nuclear stopping  

E-Print Network [OSTI]

Information about the nuclear matter under the extreme conditions of temperature and density and the role of symmetry energy under these conditions is still a topic of crucial importance in the present day nuclear physics research. The multifragmentation, collective flow and the nuclear stopping is among the various rare phenomenon which can be observed in heavy-ion collisions at intermediate energies. The nuclear stopping, which is sensitive towards the symmetry energy has gained a lot of interest because it provides the possibility to examine the degree of thermalization or equilibration in the matter. Aim of the present study is to pin down the nuclear stopping for the different forms of density dependent symmetry energy

Karan Singh Vinayak; Suneel Kumar

2011-07-27T23:59:59.000Z

104

Surface Symmetry Energy of Nuclear Energy Density Functionals.  

E-Print Network [OSTI]

??The thesis studies the bulk deformation properties of the Skyrme nuclear energy densityfunctionals. Following simple arguments based on the leptodermous expansion andliquid drop model, the… (more)

Nikolov, Nikola Iliev

2011-01-01T23:59:59.000Z

105

Soil Density/Moisture Gauge | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Soil Density/Moisture Gauge Soil Density/Moisture Gauge Soil Density/Moisture Gauge This scenario provides the planning instructions, guidance, and evaluation forms necessary to conduct an exercise involving a highway shipment of a soil moisture/density gauge (Class 7 - Radioactive). This exercise manual is one in a series of five scenarios developed by the Department of Energy Transportation Emergency Preparedness Program (TEPP). Responding agencies may include several or more of the following: local municipal and county fire, police, sheriff and Emergency Medical Services (EMS) personnel; state, local, and federal emergency response teams; emergency response contractors; and other emergency response resources that could potentially be provided by the carrier and the originating facility (shipper).

106

LANL | Physics | Inertial Confinement Fusion and High Energy Density  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Inertial confinement and high density Inertial confinement and high density plasma physics Using the world's most powerful lasers, Physics Division scientists are aiming to create thermonuclear burn in the laboratory. The experimental research of the Physics Division's Inertial Confinement Fusion program is conducted at the National Ignition Facility at Lawrence Livermore National Laboratory, the OMEGA Laser Facility at the University of Rochester, and the Trident Laser Facility at Los Alamos. Within inertial confinement fusion and the high energy density area, Los Alamos specializes in hohlraum energetics, symmetry tuning, warm dense matter physics, and hydrodynamics in ultra-extreme conditions. When complete, this research will enable the exploitation of fusion as an energy resource and will enable advanced research in stockpile stewardship

107

Activities of the High Energy Density Laboratory Plasmas  

E-Print Network [OSTI]

Activities of the High Energy Density Laboratory Plasmas FESAC Panel R. Betti FPA Meeting December #12;F. Beg (UCSD) B. Remington (LLNL) R. Betti (UR) (chair) R. Davidson (Princeton) P. Drake (U. Betti (UR) D. Hammer (Cornell) G. Logan (LBNL) D. Meyerhofer (UR) J. Sethian (NRL) R. Siemon (UNR) IFE

108

MAGNITUDE AND VARIANCE OF ACOUSTIC ENERGY DENSITY IN MICROCHANNEL ACOUSTOPHORESIS  

E-Print Network [OSTI]

and Martin Wiklund1 1 Dept. of Applied Physics, Royal Institute of Technology (KTH), Stockholm, SWEDEN 2 Dept modulation, Acoustic energy density, Microchannel INTRODUCTION Microchannel acoustophoresis is a powerful) causing a half-wave resonance across the channel width or height. However, a generic problem with SF

109

Quantum Chromodynamics and Nuclear Physics at Extreme Energy Density  

SciTech Connect (OSTI)

The report describes research in theoretical quantum chromodynamics, including effective field theories of hadronic interactions, properties of strongly interacting matter at extreme energy density, phenomenology of relativistic heavy ion collisions, and algorithms and numerical simulations of lattice gauge theory and other many-body systems.

Mueller, B.; Bass, S.A.; Chandrasekharan, S.; Mehen, T.; Springer, R.P.

2005-11-07T23:59:59.000Z

110

Design for a High Energy Density Kelvin-Helmholtz Experiment  

SciTech Connect (OSTI)

While many high energy density physics (HEDP) Rayleigh-Taylor and Richtmyer-Meshkov instability experiments have been fielded as part of basic HEDP and astrophysics studies, not one HEDP Kelvin-Helmholtz (KH) experiment has been successfully performed. Herein, a design for a novel HEDP x-ray driven KH experiment is presented along with supporting radiation-hydrodynamic simulation and theory.

Hurricane, O A

2007-10-29T23:59:59.000Z

111

A Method for the High Energy Density SMES—Superconducting Magnetic Energy Storage  

Science Journals Connector (OSTI)

The energy density of superconducting magnetic energy storage (SMES), 107 [J/m3] for the average magnetic field 5T is rather small compared with that of batteries which are estimated as 108 [J/m3...]. This paper ...

Y. Mitani; Y. Murakami

1990-01-01T23:59:59.000Z

112

Can the energy density of gravitational field be interpreted as dark energy?  

E-Print Network [OSTI]

After a brief review of the Maxwell-like approach to gravity we consider the issue of the negative energy of gravitational field which is a consequence of the field approach to the phenomenon of gravitation. Due to the existence of the negative field energy {\\it within} a mass body its total energy content is smaller than the positive energy assigned to its mass energy. We study the total energy content of a spherically symmetrical mass body having constant matter density, and show that its total energy content depends on its radius. We show that under certain circumstances, the total energy content of a mass body achieves negative values so that the force at its surface becomes repulsive. We apply this idea to the evolution of universe filled by matter and the negative energy density of its gravitational field. Since the negative energy density causes the negative pressure it might be considered as an agent which causes the acceleration of the universe.

V. Majernik

2008-07-31T23:59:59.000Z

113

Free-energy density functional for hard spheres  

Science Journals Connector (OSTI)

A free-energy density functional for a system of hard spheres is derived on a semiempirical basis. It is constructed to reproduce the thermodynamics and direct correlation function of a homogeneous fluid and then is tested in two highly inhomogeneous situations: the hard-wall–hard-sphere interface and the hard-sphere solid. The results are very good in both cases, showing that this density-functional model may be used with advantage in the study of the hard-sphere model by itself, or used as a reference system in a perturbative analysis.

P. Tarazona

1985-04-01T23:59:59.000Z

114

Optimizing Architectural and Structural Aspects of Buildings towards Higher Energy Efficiency  

E-Print Network [OSTI]

. INTRODUCTION The continuous rising of energy consumption is a current and global concern. On the one hand for the most important energy consumption rate, estimated at around 40% of the total energy used worldwideOptimizing Architectural and Structural Aspects of Buildings towards Higher Energy Efficiency

Boyer, Edmond

115

Linear response of homogeneous nuclear matter with energy density functionals  

E-Print Network [OSTI]

Response functions of infinite nuclear matter with arbitrary isospin asymmetry are studied in the framework of the random phase approximation. The residual interaction is derived from a general nuclear Skyrme energy density functional. Besides the usual central, spin-orbit and tensor terms it could also include other components as new density-dependent terms or three-body terms. Algebraic expressions for the response functions are obtained from the Bethe-Salpeter equation for the particle-hole propagator. Applications to symmetric nuclear matter, pure neutron matter and asymmetric nuclear matter are presented and discussed. Spin-isospin strength functions are analyzed for varying conditions of density, momentum transfer, isospin asymmetry, and temperature for some representative Skyrme functionals. Particular attention is paid to the discussion of instabilities, either real or unphysical, which could manifest in finite nuclei.

Pastore, A; Navarro, J

2014-01-01T23:59:59.000Z

116

Linear response of homogeneous nuclear matter with energy density functionals  

E-Print Network [OSTI]

Response functions of infinite nuclear matter with arbitrary isospin asymmetry are studied in the framework of the random phase approximation. The residual interaction is derived from a general nuclear Skyrme energy density functional. Besides the usual central, spin-orbit and tensor terms it could also include other components as new density-dependent terms or three-body terms. Algebraic expressions for the response functions are obtained from the Bethe-Salpeter equation for the particle-hole propagator. Applications to symmetric nuclear matter, pure neutron matter and asymmetric nuclear matter are presented and discussed. Spin-isospin strength functions are analyzed for varying conditions of density, momentum transfer, isospin asymmetry, and temperature for some representative Skyrme functionals. Particular attention is paid to the discussion of instabilities, either real or unphysical, which could manifest in finite nuclei.

A. Pastore; D. Davesne; J. Navarro

2014-12-07T23:59:59.000Z

117

Frontiers for Discovery in High Energy Density Physics  

SciTech Connect (OSTI)

The report is intended to identify the compelling research opportunities of high intellectual value in high energy density physics. The opportunities for discovery include the broad scope of this highly interdisciplinary field that spans a wide range of physics areas including plasma physics, laser and particle beam physics, nuclear physics, astrophysics, atomic and molecular physics, materials science and condensed matter physics, intense radiation-matter interaction physics, fluid dynamics, and magnetohydrodynamics

Davidson, R. C.; Katsouleas, T.; Arons, J.; Baring, M.; Deeney, C.; Di Mauro, L.; Ditmire, T.; Falcone, R.; Hammer, D.; Hill, W.; Jacak, B.; Joshi, C.; Lamb, F.; Lee, R.; Logan, B. G.; Melissinos, A.; Meyerhofer, D.; Mori, W.; Murnane, M.; Remington, B.; Rosner, R.; Schneider, D.; Silvera, I.; Stone, J.; Wilde, B.; Zajc. W.

2004-07-20T23:59:59.000Z

118

High Energy Density Physics and Exotic Acceleration Schemes  

SciTech Connect (OSTI)

The High Energy Density and Exotic Acceleration working group took as our goal to reach beyond the community of plasma accelerator research with its applications to high energy physics, to promote exchange with other disciplines which are challenged by related and demanding beam physics issues. The scope of the group was to cover particle acceleration and beam transport that, unlike other groups at AAC, are not mediated by plasmas or by electromagnetic structures. At this Workshop, we saw an impressive advancement from years past in the area of Vacuum Acceleration, for example with the LEAP experiment at Stanford. And we saw an influx of exciting new beam physics topics involving particle propagation inside of solid-density plasmas or at extremely high charge density, particularly in the areas of laser acceleration of ions, and extreme beams for fusion energy research, including Heavy-ion Inertial Fusion beam physics. One example of the importance and extreme nature of beam physics in HED research is the requirement in the Fast Ignitor scheme of inertial fusion to heat a compressed DT fusion pellet to keV temperatures by injection of laser-driven electron or ion beams of giga-Amp current. Even in modest experiments presently being performed on the laser-acceleration of ions from solids, mega-amp currents of MeV electrons must be transported through solid foils, requiring almost complete return current neutralization, and giving rise to a wide variety of beam-plasma instabilities. As keynote talks our group promoted Ion Acceleration (plenary talk by A. MacKinnon), which historically has grown out of inertial fusion research, and HIF Accelerator Research (invited talk by A. Friedman), which will require impressive advancements in space-charge-limited ion beam physics and in understanding the generation and transport of neutralized ion beams. A unifying aspect of High Energy Density applications was the physics of particle beams inside of solids, which is proving to be a very important field for diverse applications such as muon cooling, fusion energy research, and ultra-bright particle and radiation generation with high intensity lasers. We had several talks on these and other subjects, and many joint sessions with the Computational group, the EM Structures group, and the Beam Generation group. We summarize our groups' work in the following categories: vacuum acceleration schemes; ion acceleration; particle transport in solids; and applications to high energy density phenomena.

Cowan, T.; /General Atomics, San Diego; Colby, E.; /SLAC

2005-09-27T23:59:59.000Z

119

Used energy-related laboratory equipment grant program for institutions of higher learning. Eligible equipment catalog  

SciTech Connect (OSTI)

This is a listing of energy related equipment available through the Energy-Related Laboratory Equipment Grant Program which grants used equipment to institutions of higher education for energy-related research. Information included is an overview of the program, how to apply for a grant of equipment, eligibility requirements, types of equipment available, and the costs for the institution.

Not Available

1994-07-01T23:59:59.000Z

120

Ontogenetic and Seasonal Variation of Young Non-Native Fish Energy Densities in Lake Michigan  

E-Print Network [OSTI]

and temporal variation in vital rates (growth and mortality). Similarly, energy density (energy per unit wet changes to the Lake Michigan ecosystem. In fact, there is only one published energy density measure which for the resource-scarce winter period). Finally, our measured values of #12;energy density are roughly consistent

Note: This page contains sample records for the topic "higher energy 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.


121

Classical Nature of the Evolution of Dark Energy Density  

E-Print Network [OSTI]

By ignoring the local density fluctuations, we construct an uniform Higgs-field's (inflaton's) quantum theory with varying effective Planck constant ($\\hbar_{v}(t) \\propto R(t)^{-3}$) for the evolution of the dark energy density during the epoch after inflation. With presumable sufficient inflation in the very early period (time-scale is $t_{inf}$), so that $\\hbar_{v}\\to 0$, the state of universe decomposes into some decoherent components, which could be the essential meaning of phase transition, and each of them could be well described by classical mechanics for an inharmonic oscillator in the corresponding potential-well with a viscous force. We find that the cosmological constant at present is $\\Lambda_{now}\\approx 2.05\\times 10^{-3}$ eV, which is almost independent of the choice of potential for inflaton, and agrees excellently with the recent observations. In addition, we find that, during the cosmic epoch after inflation, the dark energy is almost conserved as well as the matter's energy, therefore the ...

Yuan, W; Liu, Yu-xin; Yuan, Wei

2006-01-01T23:59:59.000Z

122

Charged particles in higher dimensional homogeneous gravitational field: self-energy and self-force  

Science Journals Connector (OSTI)

A problem of self-energy and self-force for a charged point-like particle in a higher dimensional homogeneous gravitational field is considered. We study two cases, when a particle has the usual electric charg...

Valeri P. Frolov; Andrei Zelnikov

2014-10-01T23:59:59.000Z

123

SPP sales flyer for higher education | ENERGY STAR Buildings & Plants  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

higher education higher education Secondary menu About us Press room Contact Us Portfolio Manager Login Facility owners and managers Existing buildings Commercial new construction Industrial energy management Small business Service providers Service and product providers Verify applications for ENERGY STAR certification Design commercial buildings Energy efficiency program administrators Commercial and industrial program sponsors Associations State and local governments Federal agencies Tools and resources Training In This Section Campaigns Commercial building design Communications resources Energy management guidance Financial resources Portfolio Manager Products and purchasing Recognition Research and reports Service and product provider (SPP) resources Success stories Target Finder Technical documentation

124

Energy density matrix formalism for interacting quantum systems: a quantum Monte Carlo study  

SciTech Connect (OSTI)

We develop an energy density matrix that parallels the one-body reduced density matrix (1RDM) for many-body quantum systems. Just as the density matrix gives access to the number density and occupation numbers, the energy density matrix yields the energy density and orbital occupation energies. The eigenvectors of the matrix provide a natural orbital partitioning of the energy density while the eigenvalues comprise a single particle energy spectrum obeying a total energy sum rule. For mean-field systems the energy density matrix recovers the exact spectrum. When correlation becomes important, the occupation energies resemble quasiparticle energies in some respects. We explore the occupation energy spectrum for the finite 3D homogeneous electron gas in the metallic regime and an isolated oxygen atom with ground state quantum Monte Carlo techniques imple- mented in the QMCPACK simulation code. The occupation energy spectrum for the homogeneous electron gas can be described by an effective mass below the Fermi level. Above the Fermi level evanescent behavior in the occupation energies is observed in similar fashion to the occupation numbers of the 1RDM. A direct comparison with total energy differences demonstrates a quantita- tive connection between the occupation energies and electron addition and removal energies for the electron gas. For the oxygen atom, the association between the ground state occupation energies and particle addition and removal energies becomes only qualitative. The energy density matrix provides a new avenue for describing energetics with quantum Monte Carlo methods which have traditionally been limited to total energies.

Krogel, Jaron T [ORNL] [ORNL; Kim, Jeongnim [ORNL] [ORNL; Reboredo, Fernando A [ORNL] [ORNL

2014-01-01T23:59:59.000Z

125

Design of Safer High-Energy Density Materials for Lithium-Ion...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Safer High-Energy Density Materials for Lithium-Ion Cells Design of Safer High-Energy Density Materials for Lithium-Ion Cells 2012 DOE Hydrogen and Fuel Cells Program and Vehicle...

126

Vacuum energy density and pressure of a massive scalar field  

E-Print Network [OSTI]

With a view toward application of the Pauli-Villars regularization method to the Casimir energy of boundaries, we calculate the expectation values of the components of the stress tensor of a confined massive field in 1+1 space-time dimensions. Previous papers by Hays and Fulling are bridged and generalized. The Green function for the time-independent Schrodinger equation is constructed from the Green function for the whole line by the method of images; equivalently, the one-dimensional system is solved exactly in terms of closed classical paths and periodic orbits. Terms in the energy density and in the eigenvalue density attributable to the two boundaries individually and those attributable to the confinement of the field to a finite interval are distinguished so that their physical origins are clear. Then the pressure is found similarly from the cylinder kernel, the Green function associated most directly with an exponential frequency cutoff of the Fourier mode expansion. Finally, we discuss how the theory could be rendered finite by the Pauli-Villars method.

Fernando Daniel Mera; S. A. Fulling

2014-12-29T23:59:59.000Z

127

Vacuum energy density and pressure of a massive scalar field  

E-Print Network [OSTI]

With a view toward application of the Pauli-Villars regularization method to the Casimir energy of boundaries, we calculate the expectation values of the components of the stress tensor of a confined massive field in 1+1 space-time dimensions. Previous papers by Hays and Fulling are bridged and generalized. The Green function for the time-independent Schrodinger equation is constructed from the Green function for the whole line by the method of images; equivalently, the one-dimensional system is solved exactly in terms of closed classical paths and periodic orbits. Terms in the energy density and in the eigenvalue density attributable to the two boundaries individually and those attributable to the confinement of the field to a finite interval are distinguished so that their physical origins are clear. Then the pressure is found similarly from the cylinder kernel, the Green function associated most directly with an exponential frequency cutoff of the Fourier mode expansion. Finally, we discuss how the theory could be rendered finite by the Pauli-Villars method.

Fernando Daniel Mera; S. A. Fulling

2015-02-15T23:59:59.000Z

128

Supplementary material to "Curvature and frontier orbital energies in density functional theory", by Stein et al.  

E-Print Network [OSTI]

Supplementary material to "Curvature and frontier orbital energies in density functional theory and frontier orbital energies in density functional theory", by Stein et al. 2. Calculation of curvature from: [{ }] [{ }] #12;Supplementary material to "Curvature and frontier orbital energies in density functional theory

Baer, Roi

129

Higher Energy States in the CO Dimer: Millimeter-Wave Spectra and Rovibrational Calculations  

E-Print Network [OSTI]

Higher Energy States in the CO Dimer: Millimeter-Wave Spectra and Rovibrational Calculations Leonid millimeter-wave data yielded the precise location of 33 new energy levels of A+ symmetry and 20 levels of A extensive millimeter-wave measurements of the 12C16O dimer have been made, and more than 300 new spectral

130

The low-energy nuclear density of states and the saddle point approximation  

E-Print Network [OSTI]

The nuclear density of states plays an important role in nuclear reactions. At high energies, above a few MeV, the nuclear density of states is well described by a formula that depends on the smooth single particle density of states at the Fermi surface, the nuclear shell correction and the pairing energy. In this paper we present an analysis of the low energy behaviour of the nuclear density of states using the saddle point approximation and extensions to it. Furthermore, we prescribe a simple parabolic form for excitation energy, in the low energy limit, which may facilitate an easy computation of level densities.

Sanjay K. Ghosh; Byron K. Jennings

2001-07-30T23:59:59.000Z

131

Negative energy densities in integrable quantum field theories at one-particle level  

E-Print Network [OSTI]

We study the phenomenon of negative energy densities in quantum field theories with self-interaction. Specifically, we consider a class of integrable models (including the sinh-Gordon model) in which we investigate the expectation value of the energy density in one-particle states. In this situation, we classify the possible form of the stress-energy tensor from first principles. We show that one-particle states with negative energy density generically exist in non-free situations, and we establish lower bounds for the energy density (quantum energy inequalities). Demanding that these inequalities hold reduces the ambiguity in the stress-energy tensor, in some situations fixing it uniquely. Numerical results for the lowest spectral value of the energy density allow us to demonstrate how negative energy densities depend on the coupling constant and on other model parameters.

Bostelmann, Henning

2015-01-01T23:59:59.000Z

132

Energy density is an important mea-sure of fish nutritional condition and  

E-Print Network [OSTI]

indices, energy density integrates and reflects the history of fish feed- ing environments before the time218 Energy density is an important mea- sure of fish nutritional condition and is used to assess growth, construct energy budgets, and measure energy flow in ecosystems (Brett et al., 1969; Jobling

133

Azobenzene-Functionalized Carbon Nanotubes As High-Energy Density Solar Thermal Fuels  

Science Journals Connector (OSTI)

Azobenzene-Functionalized Carbon Nanotubes As High-Energy Density Solar Thermal Fuels ... Solar thermal fuels, which reversibly store solar energy in molecular bonds, are a tantalizing prospect for clean, renewable, and transportable energy conversion/storage. ... Here we present a novel solar thermal fuel, composed of azobenzene-functionalized carbon nanotubes, with the volumetric energy density of Li-ion batteries. ...

Alexie M. Kolpak; Jeffrey C. Grossman

2011-06-20T23:59:59.000Z

134

Nuclear Physics A 770 (2006) 131 Relativistic nuclear energy density functional  

E-Print Network [OSTI]

Nuclear Physics A 770 (2006) 1­31 Relativistic nuclear energy density functional constrained by low-energy 10 February 2006 Available online 3 March 2006 Abstract A relativistic nuclear energy density nuclear physics: the relationship between low-energy, non- perturbative QCD and the rich structure

Weise, Wolfram

135

Toward understanding the exchange-correlation energy and total-energy density functionals  

Science Journals Connector (OSTI)

If an accurate ground-state electron density ?0 for a system is known, it is shown from calculations on atoms that a strikingly good estimate for the total electronic energy of atoms is provided by the formula E[?0]=tsumi?i-(1-1/N)J[?0], where N is the number of electrons, J[?0] is the classical Coulomb repulsion energy for ?0, and the ?i are the Kohn-Sham orbital energies determined by the Zhao-Morrison-Parr procedure [Phys. Rev. A 50, 2138 (1994)] for implementation of the Levy-constrained search determination of the Kohn-Sham kinetic energy. The surprising accuracy of this formula is attributed to the fact that the exchange-correlation functional is equal to -J/N plus a functional that behaves as if it were approximately homogeneous, of degree 1 in the electron density. A corresponding exact formula is given, and various approximate models are constructed.

Robert G. Parr and Swapan K. Ghosh

1995-05-01T23:59:59.000Z

136

Spin-Multiplet Energies from Time-Dependent Density-Functional Theory  

E-Print Network [OSTI]

Spin-Multiplet Energies from Time-Dependent Density-Functional Theory M. Petersilka and E, density-functional theory (DFT) [1, 2, 3, 4, 5] has enjoyed increas- ing popularity in the #12;eld energies which is based on time-dependent density- functional theory (TDDFT) [26]. In the linear response

Gross, E.K.U.

137

Collective coordinates for nuclear spectral densities in energy transfer and femtosecond spectroscopy of molecular aggregates  

E-Print Network [OSTI]

Collective coordinates for nuclear spectral densities in energy transfer and femtosecond collective nuclear coordinates necessary to represent a given set of spectral densities is obtained coordinates phase space. The signatures of excitonic and nuclear motions in ultrafast fluorescence

Mukamel, Shaul

138

Calculations of free energies in liquid and solid phases: Fundamental measure density-functional approach  

E-Print Network [OSTI]

Calculations of free energies in liquid and solid phases: Fundamental measure density energies of liquid and solid phases using a fundamental measure density-functional theory. Namely, we can, a theoretical description of the free energies and correlation functions of hard-sphere (HS) liquid and solid

Song, Xueyu

139

Efficiency of energy funneling in the photosystem II supercomplex of higher plants  

E-Print Network [OSTI]

The investigation of energy transfer properties in photosynthetic multi-protein networks gives insight into their underlying design principles.Here, we discuss excitonic energy transfer mechanisms of the photosystem II (PS-II) C$_2$S$_2$M$_2$ supercomplex, which is the largest isolated functional unit of the photosynthetic apparatus of higher plants.Despite the lack of a decisive energy gradient in C$_2$S$_2$M$_2$, we show that the energy transfer is directed by relaxation to low energy states. C$_2$S$_2$M$_2$ is not organized to form pathways with strict energetic downhill transfer, which has direct consequences on the transfer efficiency, transfer pathways and transfer limiting steps. The exciton dynamics is sensitive to small structural changes, which, for instance, are induced by the reorganization of vibrational coordinates. In order to incorporate the reorganization process in our numerical simulations, we go beyond rate equations and use the hierarchically coupled equation of motion approach (HEOM). Wh...

Kreisbeck, Christoph

2015-01-01T23:59:59.000Z

140

Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500Wh/L  

Broader source: Energy.gov [DOE]

2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

Note: This page contains sample records for the topic "higher energy 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

Development of Large Format Lithium Ion Cells with Higher Energy Density  

Broader source: Energy.gov [DOE]

2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

142

Energy-Density Enhancement of Carbon-Nanotube-Based Supercapacitors with Redox Couple in Organic Electrolyte  

Science Journals Connector (OSTI)

Energy-Density Enhancement of Carbon-Nanotube-Based Supercapacitors with Redox Couple in Organic Electrolyte ... The redox molecule also contributes to increasing the cell capacitance by a faradaic redox reaction, and therefore the energy density of the supercapacitor can be significantly increased. ... More specifically, the addition of redox-active decamethylferrocene in an organic electrolyte results in an approximately 27-fold increase in the energy density of carbon-nanotube-based supercapacitors. ...

Jinwoo Park; Byungwoo Kim; Young-Eun Yoo; Haegeun Chung; Woong Kim

2014-11-16T23:59:59.000Z

143

Webinar: "Upgrading Renewable and Sustainable Carbohydrates for the Production of High Energy Density Fuels"  

Broader source: Energy.gov [DOE]

This webinar, part of the Biomass Program's bimonthly webinar series, featured presenters from Los Alamos National Laboratory who focused on high energy density fuels

144

Determination of the mean energy density of a light beam in an irregular thermodynamic light guide  

Science Journals Connector (OSTI)

The mean energy density of a beam of light in an irregular thermodynamic light guide with random lens shifts is calculated...

A. F. Yakubov; É. T. Bruk-Levinson; A. G. Muradyan…

1976-06-01T23:59:59.000Z

145

Coherence and Decay of Higher Energy Levels of a Superconducting Transmon Qubit  

E-Print Network [OSTI]

We present measurements of coherence and successive decay dynamics of higher energy levels of a superconducting transmon qubit. By applying consecutive $\\pi$-pulses for each sequential transition frequency, we excite the qubit from the ground state up to its fourth excited level and characterize the decay and coherence of each state. We find the decay to proceed mainly sequentially, with relaxation times in excess of 20 $\\mu$s for all transitions. We also provide a direct measurement of the charge dispersion of these levels by analyzing beating patterns in Ramsey fringes. The results demonstrate the feasibility of using higher levels in transmon qubits for encoding quantum information.

Michael J. Peterer; Samuel J. Bader; Xiaoyue Jin; Fei Yan; Archana Kamal; Ted Gudmundsen; Peter J. Leek; Terry P. Orlando; William D. Oliver; Simon Gustavsson

2014-12-12T23:59:59.000Z

146

Towards a Microscopic Reaction Description Based on Energy Density Functionals  

SciTech Connect (OSTI)

A microscopic calculation of reaction cross sections for nucleon-nucleus scattering has been performed by explicitly coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The particle-hole states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for {sup 40,48}Ca, {sup 58}Ni, {sup 90}Zr and {sup 144}Sm were described in a random-phase framework using a Skyrme functional. Reaction cross sections obtained agree very well with experimental data and predictions of a state-of-the-art fitted optical potential. Couplings between inelastic states were found to be negligible, while the pickup channels contribute significantly. The effect of resonances from higher-order channels was assessed. Elastic angular distributions were also calculated within the same method, achieving good agreement with experimental data. For the first time observed absorptions are completely accounted for by explicit channel coupling, for incident energies between 10 and 70 MeV, with consistent angular distribution results.

Nobre, G A; DIetrich, F S; Escher, J E; Thompson, I J; Dupuis, M; Terasaki, J; Engel, J

2011-09-26T23:59:59.000Z

147

The Impact of Neighbourhood Density on the Energy Demand of Passive Houses and on Potential Energy Sources from the Waste Flows and Solar Energy.  

E-Print Network [OSTI]

??This study demonstrates how the density of a neighbourhood affects its energy demand, metabolism (energy and material flows) and its ability to produce its own… (more)

Stupka, Robert

2011-01-01T23:59:59.000Z

148

Subsystem functionals in density-functional theory: Investigating the exchange energy per particle R. Armiento*  

E-Print Network [OSTI]

Subsystem functionals in density-functional theory: Investigating the exchange energy per particle; published 31 October 2002 A viable way of extending the successful use of density-functional theory for slowly varying densities and discuss the implications of our findings on the future of functional

Armiento, Rickard

149

Introduction to Density Functional Theory and Exchange-Correlation Energy Functionals  

E-Print Network [OSTI]

Introduction to Density Functional Theory and Exchange-Correlation Energy Functionals R. O. Jones.jones@fz-juelich.de Density functional calculations of cohesive and structural properties of molecules and solids can the theory and discuss the local density approximations basic to most applications, and we discuss ways

150

The National Ignition Facility: A New Era in High Energy Density Science  

SciTech Connect (OSTI)

The National Ignition Facility, the world's most energetic laser system, is now operational. This talk will describe NIF, the ignition campaign, and new opportunities in fusion energy and high energy density science enabled by NIF.

Moses, E

2009-06-10T23:59:59.000Z

151

Is Second Law of Thermodynamics Violated for Electron Transition from Lower-Energy Level to Higher-Energy Level  

E-Print Network [OSTI]

Second law of thermodynamics is applied to a few electronic processes. It is seen that the second law of thermodynamics holds good for all except one mentioned here. The classical approach, based on exact equivalence of emission and absorption spectra, for electron transition from lower energy level (first orbit) to higher energy level (second orbit) violates the second law of thermodynamics. But since second law which implies irreversibility and is universally true, a new explanation of electron transition from lower to higher energy level is proposed which leads to better understanding of several topics such as Fraunhofer lines, Optical laser. Also, interestingly, it is shown that widely different fields such as second law of thermodynamics and special relativity are in fact closely linked to each other. Also, possible links between supersymmetry and new concept of quaternion mass are mentioned.

R. C. Gupta; Ruchi Gupta; Sanjay Gupta

2003-10-05T23:59:59.000Z

152

On the breaking and restoration of symmetries within the nuclear energy density functional formalism  

E-Print Network [OSTI]

We review the notion of symmetry breaking and restoration within the frame of nuclear energy density functional methods. We focus on key differences between wave-function- and energy-functional-based methods. In particular, we point to difficulties encountered within the energy functional framework and discuss new potential constraints on the underlying energy density functional that could make the restoration of broken symmetries better formulated within such a formalism. We refer to Ref.~\\cite{duguet10a} for details.

T. Duguet; J. Sadoudi

2010-10-19T23:59:59.000Z

153

Kaon condensation in neutron stars and high density behaviour of nuclear symmetry energy  

E-Print Network [OSTI]

We study the influence of a high density behaviour of the nuclear symmetry energy on a kaon condensation in neutron stars. We find that the symmetry energy typical for several realistic nuclear potentials, which decreases at high densities, inhibits kaon condensation for weaker kaon-nucleon couplings. There exists a threshold coupling above which the kaon condensate forms at densities exceeding some critical value. This is in contrast to the case of rising symmetry energy, as e.g. for relativistic mean field models, when the kaon condensate can form for any coupling at a sufficiently high density. Properties of the condensate are also different in both cases.

S. Kubis; M. Kutschera

1999-07-24T23:59:59.000Z

154

Toward high-energy-density, high-efficiency, and moderate-temperature chip-scale thermophotovoltaics  

E-Print Network [OSTI]

- thermophotovoltaic (TPV) generator. The approach is predicted to be capable of up to 32% efficient heat, generating 344 mW of electric power over a 1-cm2 area. catalytic combustion | micro generator | thermal the energy density to 0.2 kWh/kg, whereas many hydrocarbon fuels have energy densities closer to 12 k

Soljaèiæ, Marin

155

Probability-density function for energy perturbations of isolated optical pulses  

E-Print Network [OSTI]

Probability-density function for energy perturbations of isolated optical pulses C. J. Mc to determine the probability-density function (PDF) for noise-induced energy perturbations of isolated (solitary) optical pulses in fiber communication systems. The analytical formula is consistent

Lakoba, Taras I.

156

Constraints on the density dependence of the symmetry energy from heavy ion collisions  

E-Print Network [OSTI]

Constraints on the Equation of State for symmetric matter (equal neutron and proton numbers) have been extracted from energetic collisions of heavy ions over a range of energies. Collisions of neutron-deficient and neutron-rich heavy ions now provide initial constraints on the EoS of neutron-rich matter at sub-saturation densities from isospin diffusions and neutron proton ratios. This article reviews the experimental constraints on the density dependence of Symmetry Energy at sub-saturation density.

Tsang, M B; Coupland, D; Danielewicz, P; Famiano, F; Hodges, R; Kilburn, M; Lu, F; Lynch, W G; Winkelbauer, J; Youngs, M; Zhang, YingXun

2011-01-01T23:59:59.000Z

157

Constraints on the density dependence of the symmetry energy from heavy ion collisions  

E-Print Network [OSTI]

Constraints on the Equation of State for symmetric matter (equal neutron and proton numbers) have been extracted from energetic collisions of heavy ions over a range of energies. Collisions of neutron-deficient and neutron-rich heavy ions now provide initial constraints on the EoS of neutron-rich matter at sub-saturation densities from isospin diffusions and neutron proton ratios. This article reviews the experimental constraints on the density dependence of Symmetry Energy at sub-saturation density.

M. B. Tsang; Z. Chajecki; D. Coupland; P. Danielewicz; F. Famiano; R. Hodges; M. Kilburn; F. Lu; W. G. Lynch; J. Winkelbauer; M. Youngs; YingXun Zhang

2011-01-19T23:59:59.000Z

158

Determining the density content of symmetry energy and neutron skin: an empirical approach  

E-Print Network [OSTI]

The density dependence of nuclear symmetry energy remains poorly constrained. Starting from precise empirical values of the nuclear volume and surface symmetry energy coefficients and the nuclear saturation density, we show how in the ambit of microscopic calculations with different energy density functionals, the value of the symmetry energy slope parameter $L$ alongwith that for neutron skin can be put in tighter bounds. The value of $L$ is found to be $L$= 64$\\pm $5 MeV. For $^{208}$Pb, the neutron skin thickness comes out to be 0.188 $\\pm $0.014 fm. Knowing $L$, the method can be applied to predict neutron skins of other nuclei.

Agrawal, B K; Samaddar, S K

2012-01-01T23:59:59.000Z

159

Determining the Density Content of Symmetry Energy and Neutron Skin: An Empirical Approach  

Science Journals Connector (OSTI)

The density dependence of nuclear symmetry energy remains poorly constrained. Starting from precise empirical values of the nuclear volume and surface symmetry energy coefficients and the nuclear saturation density, we show how in the ambit of microscopic calculations with different energy density functionals, the value of the symmetry energy slope parameter L along with that for neutron skin can be put in tighter bounds. The value of L is found to be L=64±5??MeV. For Pb208, the neutron skin thickness comes out to be 0.188±0.014??fm. Knowing L, the method can be applied to predict neutron skin thicknesses of other nuclei.

B. K. Agrawal; J. N. De; S. K. Samaddar

2012-12-26T23:59:59.000Z

160

Determining the density content of symmetry energy and neutron skin: an empirical approach  

E-Print Network [OSTI]

The density dependence of nuclear symmetry energy remains poorly constrained. Starting from precise empirical values of the nuclear volume and surface symmetry energy coefficients and the nuclear saturation density, we show how in the ambit of microscopic calculations with different energy density functionals, the value of the symmetry energy slope parameter $L$ alongwith that for neutron skin can be put in tighter bounds. The value of $L$ is found to be $L$= 64$\\pm $5 MeV. For $^{208}$Pb, the neutron skin thickness comes out to be 0.188 $\\pm $0.014 fm. Knowing $L$, the method can be applied to predict neutron skins of other nuclei.

B. K. Agrawal; J. N. De; S. K. Samaddar

2012-12-03T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions  

E-Print Network [OSTI]

We review recent progress in the determination of the subsaturation density behavior of the nuclear symmetry energy from heavy-ion collisions as well as the theoretical progress in probing the high density behavior of the symmetry energy in heavy-ion reactions induced by high energy radioactive beams. We further discuss the implications of these results for the nuclear effective interactions and the neutron skin thickness of heavy nuclei.

Lie-Wen Chen; Che Ming Ko; Bao-An Li; Gao-Chan Yong

2007-11-12T23:59:59.000Z

162

File:Air Density Lab.pdf | Open Energy Information  

Open Energy Info (EERE)

Air Density Lab.pdf Air Density Lab.pdf Jump to: navigation, search File File history File usage Metadata File:Air Density Lab.pdf Size of this preview: 463 × 599 pixels. Other resolution: 464 × 600 pixels. Go to page 1 2 3 4 Go! next page → next page → Full resolution ‎(1,275 × 1,650 pixels, file size: 240 KB, MIME type: application/pdf, 4 pages) File history Click on a date/time to view the file as it appeared at that time. Date/Time Thumbnail Dimensions User Comment current 09:36, 3 January 2014 Thumbnail for version as of 09:36, 3 January 2014 1,275 × 1,650, 4 pages (240 KB) Foteri (Talk | contribs) Category:Wind for Schools Portal CurriculaCategory:Wind for Schools High School Curricula You cannot overwrite this file. Edit this file using an external application (See the setup

163

Isospin coupling-channel decomposition of nuclear symmetry energy in covariant density functional theory  

E-Print Network [OSTI]

The isospin coupling-channel decomposition of the potential energy density functional is carried out within the covariant density functional theory, and their isospin and density dependence in particular the influence on the symmetry energy is studied. It is found that both isospin-singlet and isospin-triplet components of the potential energy play the dominant role in deciding the symmetry energy, especially when the Fock diagram is introduced. The results illustrate a quite different mechanism to the origin of the symmetry energy from the microscopic Brueckner-Hartree-Fock theory, and demonstrate the importance of the Fork diagram in the CDF theory, especially from the isoscalar mesons, in the isospin properties of the in-medium nuclear force at high density.

Qian Zhao; Bao Yuan Sun; Wen Hui Long

2014-11-23T23:59:59.000Z

164

Isospin coupling-channel decomposition of nuclear symmetry energy in covariant density functional theory  

E-Print Network [OSTI]

The isospin coupling-channel decomposition of the potential energy density functional is carried out within the covariant density functional theory, and their isospin and density dependence in particular the influence on the symmetry energy is studied. It is found that both isospin-singlet and isospin-triplet components of the potential energy play the dominant role in deciding the symmetry energy, especially when the Fock diagram is introduced. The results illustrate a quite different mechanism to the origin of the symmetry energy from the microscopic Brueckner-Hartree-Fock theory, and demonstrate the importance of the Fork diagram in the CDF theory, especially from the isoscalar mesons, in the isospin properties of the in-medium nuclear force at high density.

Zhao, Qian; Long, Wen Hui

2014-01-01T23:59:59.000Z

165

Effects of the symmetry energy on properties of neutron star crusts near the neutron drip density  

E-Print Network [OSTI]

We study the effects of the symmetry energy on the neutron drip density and properties of nuclei in neutron star crusts. The nonuniform matter around the neutron drip point is calculated by using the Thomas--Fermi approximation with the relativistic mean-field model. The neutron drip density and the composition of the crust are found to be correlated with the symmetry energy and its slope. We compare the self-consistent Thomas--Fermi approximation with other treatments of surface and Coulomb energies and find that these finite-size effects play an essential role in determining the equilibrium state at low density.

S. S. Bao; J. N. Hu; Z. W. Zhang; H. Shen

2014-10-03T23:59:59.000Z

166

Symmetry energy effects on properties of neutron star crusts around the neutron drip density  

E-Print Network [OSTI]

We study the effects of the symmetry energy on the neutron drip density and properties of nuclei in neutron star crusts. The nonuniform matter around the neutron drip point is calculated using the Thomas--Fermi approximation with the relativistic mean-field model. The neutron drip density and the composition of the crust are found to be correlated with the symmetry energy and its slope. We compare the self-consistent Thomas--Fermi approximation with other treatments of surface and Coulomb energies, and find that these finite-size effects play an essential role in determining the equilibrium state at low density.

Bao, S S; Zhang, Z W; Shen, H

2014-01-01T23:59:59.000Z

167

On the Energy-Momentum Density of Gravitational Plane Waves  

E-Print Network [OSTI]

By embedding Einstein's original formulation of GR into a broader context we show that a dynamic covariant description of gravitational stress-energy emerges naturally from a variational principle. A tensor $T^G$ is constructed from a contraction of the Bel tensor with a symmetric covariant second degree tensor field $\\Phi$ and has a form analogous to the stress-energy tensor of the Maxwell field in an arbitrary space-time. For plane-fronted gravitational waves helicity-2 polarised (graviton) states can be identified carrying non-zero energy and momentum.

T. Dereli; R. W. Tucker

2004-01-20T23:59:59.000Z

168

Accelerating the convergence of the total energy evaluation in density functional theory calculations  

E-Print Network [OSTI]

Accelerating the convergence of the total energy evaluation in density functional theory.1063/1.2821101 I. INTRODUCTION Density functional theory DFT ,1,2 one of the most widely used first functional theory OO-DFT B. Zhou and Y. A. Wang, J. Chem. Phys. 124, 081107 2006 is that the second

Wang, Yan Alexander

169

High energy density micro plasma bunch from multiple laser interaction with thin target  

SciTech Connect (OSTI)

Three-dimensional particle-in-cell simulation is used to investigate radiation-pressure driven acceleration and compression of small solid-density plasma by intense laser pulses. It is found that multiple impacts by presently available short-pulse lasers on a small hemispheric shell target can create a long-living tiny quasineutral monoenergetic plasma bunch of very high energy density.

Xu, Han [National Laboratory for Parallel and Distributed Processing, College of Computer Science, National University of Defense Technology, Changsha 410073 (China); Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, Wei; Luan, S. X.; Xu, Z. Z. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, M. Y., E-mail: myyu@zju.edu.cn [Physics Department, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, Bochum D-44780 (Germany); Cai, H. B.; Zhou, C. T. [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yang, X. H.; Yin, Y.; Zhuo, H. B. [College of Science, National University of Defense Technology, Changsha (China); Wang, J. W. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Murakami, M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan)

2014-01-13T23:59:59.000Z

170

Battery concepts for high density energy storage: Principles and practice. C. Austen Angell  

E-Print Network [OSTI]

Battery concepts for high density energy storage: Principles and practice. C. Austen Angell Dept such as the lithium-air battery, and the more advanced zinc-air battery in which only the source needs to be "bottled

Angell, C. Austen

171

Optimization of Polymer-based Nanocomposites for High Energy Density Applications  

E-Print Network [OSTI]

polymers are of interest owing to their high inherent electrical resistance, low dielectric loss, flexibility, light weight, and low cost; however, capacitors produced with dielectric polymers are limited to an energy density of ~1-2 J/cc. Polymer...

Barhoumi Ep Meddeb, Amira

2012-07-16T23:59:59.000Z

172

High Energy Density Sate, Material and Device with High Power Lasers  

Science Journals Connector (OSTI)

High energy density states with photon pressures of more than Tera bar and thermal pressure of more than Mega bar, is now available with high power lasers. Here I present creation of...

Kodama, R

173

High Energy Density Li-ion Cells for EVs Based on Novel, High...  

Broader source: Energy.gov (indexed) [DOE]

Storage Systems Vehicle Technologies Annual Merit Review 6182014 1 High Energy Density Li-ion Cells for EV's Based on Novel, High Voltage Cathode Material Systems Keith D. Kepler...

174

Reducing Register Ports for Higher Speed and Lower Energy Il Park, Michael D. Powell, and T. N. Vijaykumar  

E-Print Network [OSTI]

Reducing Register Ports for Higher Speed and Lower Energy Il Park, Michael D. Powell, and T. N]. Both large size and high numbers of ports result in slow access and high energy dissipation. The key are access time and energy. While previ- ous work has focused on reducing the number of registers, we propose

Vijaykumar, T. N.

175

Report of the Interagency Task Force on High Energy Density Physics  

SciTech Connect (OSTI)

Identifies the needs for improving Federal stewardship of specific aspects of high energy density physics, particularly the study of high energy density plasmas in the laboratory, and strengthening university activities in this latter discipline. The report articulates how HEDP fits into the portfolio of federally funded missions and includes agency actions to be taken that are necessary to further this area of study consistent with Federal priorities and plans, while being responsive to the needs of the scientific community.

None

2007-08-01T23:59:59.000Z

176

An Exact Calculation of the Energy Density of Cosmological Gravitational Waves  

E-Print Network [OSTI]

In this paper we calculate the Bogoliubov coefficients and the energy density of the stochastic gravitational wave background for a universe that undergoes inflation followed by radiation domination and matter domination, using a formalism that gives the Bogoliubov coefficients as continous functions of time. By making a reasonable assumption for the equation of state during reheating, we obtain in a natural way the expected high frequency cutoff in the spectral energy density.

L. E. Mendes; A. B. Henriques; R. G. Moorhouse

1994-10-24T23:59:59.000Z

177

The National Ignition Facility: The Path to Ignition, High Energy Density Science and Inertial Fusion Energy  

SciTech Connect (OSTI)

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is a Nd:Glass laser facility capable of producing 1.8 MJ and 500 TW of ultraviolet light. This world's most energetic laser system is now operational with the goals of achieving thermonuclear burn in the laboratory and exploring the behavior of matter at extreme temperatures and energy densities. By concentrating the energy from its 192 extremely energetic laser beams into a mm{sup 3}-sized target, NIF can produce temperatures above 100 million K, densities of 1,000 g/cm{sup 3}, and pressures 100 billion times atmospheric pressure - conditions that have never been created in a laboratory and emulate those in the interiors of planetary and stellar environments. On September 29, 2010, NIF performed the first integrated ignition experiment which demonstrated the successful coordination of the laser, the cryogenic target system, the array of diagnostics and the infrastructure required for ignition. Many more experiments have been completed since. In light of this strong progress, the U.S. and the international communities are examining the implication of achieving ignition on NIF for inertial fusion energy (IFE). A laser-based IFE power plant will require a repetition rate of 10-20 Hz and a 10% electrical-optical efficiency laser, as well as further advances in large-scale target fabrication, target injection and tracking, and other supporting technologies. These capabilities could lead to a prototype IFE demonstration plant in 10- to 15-years. LLNL, in partnership with other institutions, is developing a Laser Inertial Fusion Energy (LIFE) baseline design and examining various technology choices for LIFE power plant This paper will describe the unprecedented experimental capabilities of the NIF, the results achieved so far on the path toward ignition, the start of fundamental science experiments and plans to transition NIF to an international user facility providing access to researchers around the world. The paper will conclude with a discussion of LIFE, its development path and potential to enable a carbon-free clean energy future.

Moses, E

2011-03-25T23:59:59.000Z

178

ESS 2012 Peer Review - Novel High Energy Density Dielectrics for Scalable Capacitor Needs - Geoff Brennecka, SNL  

Broader source: Energy.gov (indexed) [DOE]

Novel High Energy Density Novel High Energy Density Dielectrics for Scalable Capacitor Needs 27 September 2012 Geoff Brennecka The author gratefully acknowledges the support of Dr. Imre Gyuk and the Department of Energy's Office of Electricity Delivery and Energy Reliability. 400nF 2000V Project  Currently-available capacitor options force undesired choices:  (power, capacitance) vs. reliability  performance vs. (temperature, voltage) stability  Capacitors are often not deployed where they could be beneficial, or are deployed and fail (or are severely derated)  Stationary storage and related applications can realize significant value via improved capacitor performance and reliability  Improve reliability and efficiency of high temperature power electronics

179

Excitation energies of molecules within time-independent density functional theory  

SciTech Connect (OSTI)

Recently proposed exchange energy functional for excited-states is tested for obtaining excitation energies of diatomic molecules. The functional is the ground-state counterpart of the local-density approximation, the modified local spin density (MLSD). The MLSD functional is tested for the N{sub 2} and CO diatomic molecules. The excitation energy obtained with the MLSD functional for the N{sub 2} molecule is in close vicinity to that obtained from the exact exchange orbital functional, Krieger, Li and Iafrate (KLI). For the CO molecule, the departure in excitation energy is observed and is due to the overcorrection of self-interaction.

Hemanadhan, M., E-mail: hemanadh@iitk.ac.in; Harbola, Manoj K., E-mail: hemanadh@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur, Kanpur-208016 (India)

2014-04-24T23:59:59.000Z

180

Capture of Solar and Higher-Energy Neutrinos by Iodine 127  

E-Print Network [OSTI]

We discuss and improve a recent treatment of the absorption of solar neutrinos by ${}^{127}$I, in connection with a proposed solar neutrino detector. With standard-solar-model fluxes and an in-medium value of -1.0 for the axial-vector coupling constant $g_A$, we obtain a ${}^8$B-neutrino cross section of 3.3$\\times 10^{-42}$, about 50\\% larger than in our previous work, and a ${}^7$Be cross section that is less certain but nevertheless also larger than before. We then apply the improved techniques to higher incoming energies that obtain at the LAMPF beam dump, where an experiment is underway to finalize a calibration of the ${}^{127}$I with electron neutrinos from muon decay. We find that forbidden operators, which play no role in solar-neutrino absorption, contribute nonnegligibly to the LAMPF cross section, and that the preliminary LAMPF mean value is significantly larger than our prediction.

J. Engel; S. Pittel; P. Vogel

1994-02-17T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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.


181

From Brueckner Approach to Skyrme-type Energy Density Functional  

E-Print Network [OSTI]

A Skyrme-like effective interaction is built up from the equation of state of nuclear matter. The latter is calculated in the framework of the Brueckner-Hartree-Fock approximation with two and three body forces. A complete Skyrme parametrization requires a fit of the neutron and proton effective masses and also the Landau parameters. The new parametrization is probed on the properties of a set of closed-shell and closed-subshell nuclei, including binding energies and charge radii.

L. G. Cao; U. Lombardo; C. W. Shen; Nguyen Van Giai

2005-07-27T23:59:59.000Z

182

Angular Momentum and Energy-Momentum Densities as Gauge Currents  

E-Print Network [OSTI]

If we replace the general spacetime group of diffeomorphisms by transformations taking place in the tangent space, general relativity can be interpreted as a gauge theory, and in particular as a gauge theory for the Lorentz group. In this context, it is shown that the angular momentum and the energy-momentum tensors of a general matter field can be obtained from the invariance of the corresponding action integral under transformations taking place, not in spacetime, but in the tangent space, in which case they can be considered as gauge currents.

M. Calcada; J. G. Pereira

2002-07-11T23:59:59.000Z

183

Measurement of the pseudorapidity and centrality dependence of the transverse energy density in PbPb collisions at sqrt(s[NN]) = 2.76 TeV  

E-Print Network [OSTI]

The transverse energy ET in PbPb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy sqrt(s[NN]) has been measured over a broad range of pseudorapidity eta and collision centrality using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity d(ET)/d(eta) increases faster with collision energy than the charged particle multiplicity. This implies that the mean energy per particle is increasing with collision energy. At all pseudorapidities the transverse energy per participating nucleon increases with the centrality of the collision. The ratio of transverse energy per unit pseudorapidity in peripheral to central collisions varies significantly as the pseudorapidity increases from eta = 0 to abs(eta) = 5.0. For the 5% most central collisions the energy density per unit volume is estimated to be about 14 GeV/fm^3 at a time of 1 fm/c after the collision. This is about 100 times larger than normal nuclear matter density and a factor of 2.6 times higher than the energy density reported at sqrt(s[NN]) = 200 GeV at RHIC.

CMS Collaboration

2012-05-11T23:59:59.000Z

184

Measurement of the Pseudorapidity and Centrality Dependence of the Transverse Energy Density in Pb-Pb Collisions at sNN=2.76??TeV  

Science Journals Connector (OSTI)

The transverse energy (ET) in Pb-Pb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy (sNN) has been measured over a broad range of pseudorapidity (?) and collision centrality by using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity (dET/d?) increases faster with collision energy than the charged particle multiplicity. This implies that the mean energy per particle is increasing with collision energy. At all pseudorapidities, the transverse energy per participating nucleon increases with the centrality of the collision. The ratio of transverse energy per unit pseudorapidity in peripheral to central collisions varies significantly as the pseudorapidity increases from ?=0 to |?|=5.0. For the 5% most central collisions, the energy density per unit volume is estimated to be about 14??GeV/fm3 at a time of 1??fm/c after the collision. This is about 100 times larger than normal nuclear matter density and a factor of 2.6 times higher than the energy density reported at sNN=200??GeV at the Relativistic Heavy Ion Collider.

S. Chatrchyan et al. (CMS Collaboration)

2012-10-08T23:59:59.000Z

185

Unbiased Estimate of Dark Energy Density from Type Ia Supernova Data  

Science Journals Connector (OSTI)

Type Ia supernovae (SNe Ia) are currently the best probes of the dark energy in the universe. To constrain the nature of dark energy, we assume a flat universe and that the weak energy condition is satisfied, and we allow the density of dark energy, ?X(z), to be an arbitrary function of redshift. Using simulated data from a space-based SN pencil-beam survey, we find that by optimizing the number of parameters used to parameterize the dimensionless dark energy density, f(z) = ?X(z)/?X(z = 0), we can obtain an unbiased estimate of both f(z) and the fractional matter density of the universe, ?m. A plausible SN pencil-beam survey (with a square degree field of view and for an observational duration of 1 yr) can yield about 2000 SNe Ia with 0 ? z ? 2. Such a survey in space would yield SN peak luminosities with a combined intrinsic and observational dispersion of ?(mint) = 0.16 mag. We find that for such an idealized survey, ?m can be measured to 10% accuracy, and the dark energy density can be estimated to ~20% to z ~ 1.5, and ~20%-40% to z ~ 2, depending on the time dependence of the true dark energy density. Dark energy densities that vary more slowly can be more accurately measured. For the anticipated Supernova/Acceleration Probe (SNAP) mission, ?m can be measured to 14% accuracy, and the dark energy density can be estimated to ~20% to z ~ 1.2. Our results suggest that SNAP may gain much sensitivity to the time dependence of the dark energy density and ?m by devoting more observational time to the central pencil-beam fields to obtain more SNe Ia at z > 1.2. We use both a maximum likelihood analysis and a Monte Carlo analysis (when appropriate) to determine the errors of estimated parameters. We find that the Monte Carlo analysis gives a more accurate estimate of the dark energy density than the maximum likelihood analysis.

Yun Wang; Geoffrey Lovelace

2001-01-01T23:59:59.000Z

186

Effective bridge spectral density for long-range biological energy and charge transfer  

E-Print Network [OSTI]

Effective bridge spectral density for long-range biological energy and charge transfer Oliver Ku of intermediate bridge sites in energy and charge transfer processes in molecular aggregates of arbitrary size analysis for a donor­acceptor system coupled through a single bridge molecule are presented. © 1996

Mukamel, Shaul

187

Thermodynamic, Energy Efficiency, and Power Density Analysis of Reverse Electrodialysis Power Generation with Natural Salinity Gradients  

Science Journals Connector (OSTI)

Thermodynamic, Energy Efficiency, and Power Density Analysis of Reverse Electrodialysis Power Generation with Natural Salinity Gradients ... solns. of different salinities. ... River mouths are potentially abundant locations for the exploitation of the clean and renewable salinity gradient energy (SGE) as here perpetually fresh water mixes with saline seawater. ...

Ngai Yin Yip; David A. Vermaas; Kitty Nijmeijer; Menachem Elimelech

2014-04-03T23:59:59.000Z

188

Present and future perspectives for high energy density physics with intense heavy ion and laser beams  

E-Print Network [OSTI]

Present and future perspectives for high energy density physics with intense heavy ion and laser18, deliver an intense uranium beam that deposit about 1 kJ0g specific energy in solid matter. Using 2004! Abstract Intense heavy ion beams from the Gesellschaft für Schwerionenforschung ~GSI, Darmstadt

189

Stationary nature of the density-functional free energy: Application to accelerated multiple-scattering calculations  

Science Journals Connector (OSTI)

The number of operations required for conventional density-functional algorithms grows as the cube of the number of atoms, N. For large systems the computing requirements are unattainable. To overcome this limitation it is acceptable to approximate those variables with respect to which the free energy is stationary. We show that the stationarity of the free energy with respect to electron density, one-electron potential, chemical potential, occupation function, and temperature allows for very useful approximations leading to rapid and accurate determination of the free energy. Here we discuss approximations involved in calculating the finite temperature electron density needed to evaluate the Harris-Foulkes free energy. Of particular importance are (1) an electron density at each site that is based on exact solution of the Poisson equation combined with a solution of the multiple-scattering problem in which only scattering from a small cluster of sites surrounding the site in question is retained and (2) an approximate occupation function having a finite number of poles in the complex energy plane. The intention is to develop, within density-functional theory, an O(N) scalable first-principles scheme, based on spatially local multiple-scattering methods, for calculating free energies of large systems.

D. M. C. Nicholson; G. M. Stocks; Y. Wang; W. A. Shelton; Z. Szotek; W. M. Temmerman

1994-11-15T23:59:59.000Z

190

Quantum mechanical constraints on the measurement of the density of the electromagnetic energy  

E-Print Network [OSTI]

It is considered constraints imposed by the quantum mechanics on the measurement of the density of the electromagnetic energy. First, the energy of the electromagnetic wave and the volume (time) are bound with the Heisenberg uncertainty principle. It reduces from double to ordinary the relativistic effect for the density of the electromagnetic energy. Second, the frequency of photons and the number of photons are bound with the Heisenberg uncertainty principle. Then relativistic effects for the frequency of photons and for the number of photons are incompatible.

D. L. Khokhlov

2004-02-05T23:59:59.000Z

191

Energy enhancement of proton acceleration in combinational radiation pressure and bubble by optimizing plasma density  

SciTech Connect (OSTI)

The combinational laser radiation pressure and plasma bubble fields to accelerate protons are researched through theoretical analysis and numerical simulations. The dephasing length of the accelerated protons bunch in the front of the bubble and the density gradient effect of background plasma on the accelerating phase are analyzed in detail theoretically. The radiation damping effect on the accelerated protons energy is also considered. And it is demonstrated by two-dimensional particle-in-cell simulations that the protons bunch energy can be increased by using the background plasma with negative density gradient. However, radiation damping makes the maximal energy of the accelerated protons a little reduction.

Bake, Muhammad Ali; Xie Baisong [Key Laboratory of Beam Technology and Materials Modification of the Ministry of Education, Beijing Normal University, Beijing 100875 (China); College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); Shan Zhang [Department of Mathematics and Physics, Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Hong Xueren [College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875 (China); College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070 (China); Wang Hongyu [Department of Physics, Anshan Normal University, Anshan 114005 (China); Shanghai Bright-Tech Information Technology Co. Ltd, Shanghai 200136 (China)

2012-08-15T23:59:59.000Z

192

Full charge-density calculation of the surface energy of metals  

Science Journals Connector (OSTI)

We have calculated the surface energy and the work function of the 4d metals by means of an energy functional based on a self-consistent, spherically symmetric atomic-sphere potential. In this approach the kinetic energy is calculated completely within the atomic-sphere approximation (ASA) by means of a spherically symmetrized charge density, while the Coulomb and exchange-correlation contributions are calculated by means of the complete, nonspherically symmetric charge density within nonoverlapping, space-filling Wigner-Seitz cells. The functional is used to assess the convergence and the accuracy of the linear-muffin-tin-orbitals (LMTO) method and the ASA in surface calculations. We find that the full charge-density functional improves the agreement with recent full-potential LMTO calculations to a level where the average deviation in surface energy over the 4d series is down to 10%.

L. Vitos; J. Kollár; H. L. Skriver

1994-06-15T23:59:59.000Z

193

Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source  

Science Journals Connector (OSTI)

In order to perform material interaction studies with intense extreme ultraviolet(EUV)radiation a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10× demagnified imaging of the plasma a maximum pulse energy density of ? 0.73 ? J / cm 2 at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate polycarbonate and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data etch rates were determined revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore the surface roughness of the structuredpolymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface indicating a rather smooth etch process (roughness increase of 20%–30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates having consequences for the proper use of polymerablation for beam profiling of focused EUVradiation.

Frank Barkusky; Armin Bayer; Christian Peth; Klaus Mann

2009-01-01T23:59:59.000Z

194

Direct photoetching of polymers using radiation of high energy density from a table-top extreme ultraviolet plasma source  

SciTech Connect (OSTI)

In order to perform material interaction studies with intense extreme ultraviolet (EUV) radiation, a Schwarzschild mirror objective coated with Mo/Si multilayers was adapted to a compact laser-driven EUV plasma source utilizing a solid Au target. By 10x demagnified imaging of the plasma a maximum pulse energy density of {approx}0.73 J/cm{sup 2} at a wavelength of 13.5 nm can be achieved in the image plane of the objective at a pulse duration of 8.8 ns. In this paper we present EUV photoetching rates measured for polymethyl methacrylate, polycarbonate, and polytetrafluoroethylene at various fluence levels. A linear dependence between etch depth and applied EUV pulse number could be observed without the necessity for any incubation pulses. By evaluating the slope of these data, etch rates were determined, revealing also a linear behavior for low fluences. A threshold energy density could not be observed. The slope of the linear etch regime as well as deviations from the linear trend at higher energy densities are discussed and compared to data known from deep UV laser ablation. Furthermore, the surface roughness of the structured polymers was measured by atomic force microscopy and compared to the nonirradiated polymer surface, indicating a rather smooth etch process (roughness increase of 20%-30%). The different shapes of the etch craters observed for the three polymers at high energy densities can be explained by the measured fluence dependence of the etch rates, having consequences for the proper use of polymer ablation for beam profiling of focused EUV radiation.

Barkusky, Frank; Bayer, Armin; Peth, Christian; Mann, Klaus [Laser-Laboratorium-Goettingen e.V., Hans-Adolf-Krebs-Weg 1, D-37077 Goettingen (Germany)

2009-01-01T23:59:59.000Z

195

Ultra-high energy cosmic ray investigations by means of EAS muon density measurements  

E-Print Network [OSTI]

A new approach to investigations of ultra-high energy cosmic rays based on the ground-level measurements of the spectra of local density of EAS muons at various zenith angles is considered. Basic features of the local muon density phenomenology are illustrated using a simple semi-analytical model. It is shown that muon density spectra are sensitive to the spectrum slope, primary composition, and to the features of hadronic interaction. New experimental data on muon bundles at zenith angles from 30 degrees to horizon obtained with the coordinate detector DECOR are compared with CORSIKA-based simulations. It is found that measurements of muon density spectra in inclined EAS give possibility to study characteristics of primary cosmic ray flux in a very wide energy range from 10^15 to 10^19 eV.

N. S. Barbashina; A. G. Bogdanov; D. V. Chernov; A. N. Dmitrieva; D. M. Gromushkin; V. V. Kindin; R. P. Kokoulin; K. G. Kompaniets; G. Mannocchi; A. A. Petrukhin; O. Saavedra; V. V. Shutenko; D. A. Timashkov; G. Trinchero; I. I. Yashin

2007-01-11T23:59:59.000Z

196

Probing the Evolution of the Dark Energy Density with Future Supernova Surveys  

E-Print Network [OSTI]

The time dependence of the dark energy density can be an important clue to the nature of dark energy in the universe. We show that future supernova data from dedicated telescopes (such as SNAP), when combined with data of nearby supernovae, can be used to determine how the dark energy density $\\rho_X(z)$ depends on redshift, if $\\rho_X(z)$ is not too close to a constant. For quantitative comparison, we have done an extensive study of a number of dark energy models. Based on these models we have simulated data sets in order to show that we can indeed reconstruct the correct sign of the time dependence of the dark energy density, outside of a degeneracy region centered on $1+w_0 = -w_1 z_{max}/3$ (where $z_{max}$ is the maximum redshift of the survey, e.g., $z_{max}=1.7$ for SNAP). We emphasize that, given the same data, one can obtain much more information about the dark energy density directly (and its time dependence) than about its equation of state.

Yun Wang; Veselin Kostov; Katherine Freese; Joshua A. Frieman; Paolo Gondolo

2004-02-03T23:59:59.000Z

197

Role of exchange in density-functional theory for weakly interacting systems: Quantum Monte Carlo analysis of electron density and interaction energy  

E-Print Network [OSTI]

We analyze the density-functional theory (DFT) description of weak interactions by employing diffusion and reptation quantum Monte Carlo (QMC) calculations, for a set of benzene-molecule complexes. While the binding energies ...

Grossman, Jeffrey C.

198

Large two-dimensional electronic systems: Self-consistent energies and densities at low cost  

Science Journals Connector (OSTI)

We derive a self-consistent local variant of the Thomas-Fermi approximation for (quasi-) two-dimensional (2D) systems by localizing the Hartree term. The scheme results in an explicit orbital-free representation of the electron density and energy in terms of the external potential, the number of electrons, and the chemical potential determined upon normalization. We test the method over a variety 2D nanostructures by comparing to the Kohn-Sham 2D local-density approximation (LDA) calculations up to 600 electrons. Accurate results are obtained in view of the negligible computational cost. We also assess a local upper bound for the Hartree energy.

E. Räsänen; S. Pittalis; G. Bekçio?lu; I. Makkonen

2013-01-31T23:59:59.000Z

199

Exotic Low Density Fermion States in the Two Measures Field Theory: Neutrino Dark Energy  

E-Print Network [OSTI]

We study a new field theory effect in the cosmological context in the Two Measures Field Theory (TMT). TMT is an alternative gravity and matter field theory where the gravitational interaction of fermionic matter is reduced to that of General Relativity when the energy density of the fermion matter is much larger than the dark energy density. In this case also the 5-th force problem is solved automatically. In the opposite limit, where the magnitudes of fermionic energy density and scalar field dark energy density become comparable, nonrelativistic fermions can participate in the cosmological expansion in a very unusual manner. Some of the features of such states in a toy model of the late time universe filled with homogeneous scalar field and uniformly distributed nonrelativistic neutrinos: neutrino mass increases as m ~ a^{3/2}; the neutrino gas equation-of-state approaches w=-1, i.e. neutrinos behave as a sort of dark energy; the total (scalar field + neutrino) equation-of-state also approaches w=-1; the t...

Guendelman, E I

2006-01-01T23:59:59.000Z

200

vol. 155, no. 2 the american naturalist february 2000 Energy, Density, and Constraints to Species Richness: Ant  

E-Print Network [OSTI]

. This supports the energy limitation hypothesis' assumption that average population densities are highervol. 155, no. 2 the american naturalist february 2000 Energy, Density, and Constraints to Species in a given time and space. The energy limitation hy- pothesis links the species richness of consumer taxa

Kaspari, Mike

Note: This page contains sample records for the topic "higher energy 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

Energy Department Announces Funding to Access Higher Quality Wind Resources and Lower Costs  

Office of Energy Efficiency and Renewable Energy (EERE)

The Energy Department today announced $2 million to help efficiently harness wind energy using taller towers. These projects will help strengthen U.S. wind turbine component manufacturing, reduce...

202

Stochastic thermodynamics of fluctuating density fields: Non-equilibrium free energy differences under coarse-graining  

SciTech Connect (OSTI)

We discuss the stochastic thermodynamics of systems that are described by a time-dependent density field, for example, simple liquids and colloidal suspensions. For a time-dependent change of external parameters, we show that the Jarzynski relation connecting work with the change of free energy holds if the time evolution of the density follows the Kawasaki-Dean equation. Specifically, we study the work distributions for the compression and expansion of a two-dimensional colloidal model suspension implementing a practical coarse-graining scheme of the microscopic particle positions. We demonstrate that even if coarse-grained dynamics and density functional do not match, the fluctuation relations for the work still hold albeit for a different, apparent, change of free energy.

Leonard, T.; Lander, B.; Seifert, U. [II. Institut für Theoretische Physik, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart (Germany)] [II. Institut für Theoretische Physik, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart (Germany); Speck, T. [Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf (Germany)] [Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf (Germany)

2013-11-28T23:59:59.000Z

203

Configuration mixing within the energy density functional formalism: pathologies and cures  

E-Print Network [OSTI]

Configuration mixing calculations performed in terms of the Skyrme/Gogny Energy Density Functional (EDF) rely on extending the Single-Reference energy functional into non-diagonal EDF kernels. The standard way to do so, based on an analogy with the pure Hamiltonian case and the use of the generalized Wick theorem, is responsible for the recently observed divergences and steps in Multi-Reference calculations. We summarize here the minimal solution to this problem recently proposed [Lacroix et al, arXiv:0809.2041] and applied with success to particle number restoration[Bender et al, arXiv:0809.2045]. Such a regularization method provides suitable corrections of pathologies for EDF depending on integer powers of the density. The specific case of fractional powers of the density[Duguet et al, arXiv:0809.2049] is also discussed.

Denis Lacroix; Michael Bender; Thomas Duguet

2008-11-14T23:59:59.000Z

204

OBSERVATIONS AND COMPUTATIONS OF HIGHER ENERGY COLLECTIVE EFFECTS IN THE FERMILAB BOOSTER  

E-Print Network [OSTI]

Energy Collective Effects in the Fermilab Booster* Massimoin during my visit to Fermilab in November and December

Cornacchia, M.

2010-01-01T23:59:59.000Z

205

Juvenile salmon with high standard metabolic rates have higher energy costs but can process meals faster  

Science Journals Connector (OSTI)

...a greater total energy expenditure when...shorter. The greater energy costs they incur...their assimilation efficiency. These relationships...as the level of energy consumption when...defended, such as pools in rivers (Nakano...insufficient to prompt swimming, and therefore...

2009-01-01T23:59:59.000Z

206

High energy density, thin-lm, rechargeable lithium batteries for marine eld operations  

E-Print Network [OSTI]

High energy density, thin-®lm, rechargeable lithium batteries for marine ®eld operations Biying February 2001 Abstract All solid state, thin-®lm batteries with the cell con®guration of VOx, no binder) cathode consisted of a dense ®lm of vanadium oxide (200 nm thick), deposited on aluminum foil

Sadoway, Donald Robert

207

PLASMA FOCUSING OF HIGH ENERGY DENSITY ELECTRON AND POSITRON BEAMS \\Lambda  

E-Print Network [OSTI]

PLASMA FOCUSING OF HIGH ENERGY DENSITY ELECTRON AND POSITRON BEAMS \\Lambda J.S.T. Ng, P. Chen, W, for the first time, positron beams. We also discuss measure­ ments on plasma lens­induced synchrotron radiation and laser­ and beam­plasma interactions. 1 INTRODUCTION The plasma lens was proposed as a final focusing

208

Further Study on the Conservation Laws of Energy-momentum Tensor Density for a Gravitational System  

E-Print Network [OSTI]

The various methods to derive Einstein conservation laws and the relevant definitions of energy-momentum tensor density for gravitational fields are studied in greater detail. It is shown that these methods are all equivalent. The study on the identical and different characteristics between Lorentz and Levi-Civita conservation laws and Einstein conservation laws is thoroughly explored. Whether gravitational waves carry the energy-momentum is discussed and some new interpretations for the energy exchanges in the gravitational systems are given. The viewpoint that PSR1913 does not verify the gravitational radiation is confirmed.

Chen Fang-Pei

2008-05-21T23:59:59.000Z

209

Weighted-density functionals for cavity formation and dispersion energies in continuum solvation models  

E-Print Network [OSTI]

Continuum solvation models enable efficient first principles calculations of chemical reactions in solution, but require extensive parametrization and fitting for each solvent and class of solute systems. Here, we examine the assumptions of continuum solvation models in detail and replace empirical terms with physical models in order to construct a minimally-empirical solvation model. Specifically, we derive solvent radii from the nonlocal dielectric response of the solvent from ab initio calculations, construct a closed-form and parameter-free weighted-density approximation for the free energy of the cavity formation, and employ a pair-potential approximation for the dispersion energy. We show that the resulting model with a single solvent-independent parameter: the electron density threshold ($n_c$), and a single solvent-dependent parameter: the dispersion scale factor ($s_6$), reproduces solvation energies of organic molecules in water, chloroform and carbon tetrachloride with RMS errors of 1.1, 0.6 and 0....

Sundararaman, Ravishankar; Arias, T A

2014-01-01T23:59:59.000Z

210

Breast Density Assessment in Adolescent Girls Using Dual-Energy X-ray Absorptiometry: A Feasibility Study  

Science Journals Connector (OSTI)

...four measures of dietary quality (total energy, % energy from fat, FV...servings). Overall, dietary quality was poor, with mean...differences in dietary quality by drinking status; mean daily total energy intake was higher among...

John A. Shepherd; Serghei Malkov; Bo Fan; Aurelie Laidevant; Rachel Novotny; and Gertraud Maskarinec

2008-07-01T23:59:59.000Z

211

Measurements of continuous mix evolution in a high energy density shear flow  

SciTech Connect (OSTI)

We report on the novel integration of streaked radiography into a counter-flowing High Energy Density (HED) shear environment that continually measures a growing mix layer of Al separating two low-density CH foams. Measurements of the mix width allow us to validate compressible turbulence models and with streaked imaging, make this possible with a minimal number of experiments on large laser facilities. In this paper, we describe how the HED counter-flowing shear layer is created and diagnosed with streaked radiography. We then compare the streaked data to previous two-dimensional, single frame radiography and radiation hydrodynamic simulations of the experiment with inline compressible turbulent mix models.

Loomis, E., E-mail: loomis@lanl.gov; Doss, F.; Flippo, K.; Fincke, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-04-15T23:59:59.000Z

212

Accurate Ground-State Energies of Solids and Molecules from Time-Dependent Density-Functional Theory  

E-Print Network [OSTI]

-dissipation theorem with time-dependent density- functional theory. The key ingredient is a renormalization scheme be obtained from time- dependent density-functional theory (TDDFT) through the Dyson equation ð� ¼ KS ð� þ KS density-functional theory (DFT), one needs a rather involved approximation for the xc energy in order

Thygesen, Kristian

213

Kohn-Sham Kinetic Energy Density in the Nuclear and Asymptotic Regions: Deviations from the Von Weizs\\"acker Behavior and Applications to Density Functionals  

E-Print Network [OSTI]

We show that the Kohn-Sham positive-definite kinetic energy (KE) density significantly differs from the von Weizs\\"acker (VW) one at the nuclear cusp as well as in the asymptotic region. At the nuclear cusp, the VW functional is shown to be linear and the contribution of p-type orbitals to the KE density is theoretically derived and numerically demonstrated in the limit of infinite nuclear charge, as well in the semiclassical limit of neutral large atoms. In the latter case, it reaches 12 of the KE density. In the asymptotic region we find new exact constraints for meta Generalized Gradient Approximation (meta-GGA) exchange functionals: with an exchange enhancement factor proportional to $\\sqrt{\\alpha}$, where $\\alpha$ is the common meta-GGA ingredient, both the exchange energy density and the potential are proportional to the exact ones. In addition, this describes exactly the large-gradient limit of quasi-two dimensional systems.

Della Sala, F; Constantin, L A

2014-01-01T23:59:59.000Z

214

Enhanced von Weizsäcker Wang-Govind-Carter kinetic energy density functional for semiconductors  

SciTech Connect (OSTI)

We propose a new form of orbital-free (OF) kinetic energy density functional (KEDF) for semiconductors that is based on the Wang-Govind-Carter (WGC99) nonlocal KEDF. We enhance within the latter the semi-local von Weizsäcker KEDF term, which is exact for a single orbital. The enhancement factor we introduce is related to the extent to which the electron density is localized. The accuracy of the new KEDF is benchmarked against Kohn-Sham density functional theory (KSDFT) by comparing predicted energy differences between phases, equilibrium volumes, and bulk moduli for various semiconductors, along with metal-insulator phase transition pressures. We also compare point defect and (100) surface energies in silicon for a broad test of its applicability. This new KEDF accurately reproduces the exact non-interacting kinetic energy of KSDFT with only one additional adjustable parameter beyond the three parameters in the WGC99 KEDF; it exhibits good transferability between semiconducting to metallic silicon phases and between various III-V semiconductors without parameter adjustment. Overall, this KEDF is more accurate than previously proposed OF KEDFs (e.g., the Huang-Carter (HC) KEDF) for semiconductors, while the computational efficiency remains at the level of the WGC99 KEDF (several hundred times faster than the HC KEDF). This accurate, fast, and transferable new KEDF holds considerable promise for large-scale OFDFT simulations of metallic through semiconducting materials.

Shin, Ilgyou [Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009 (United States)] [Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009 (United States); Carter, Emily A., E-mail: eac@princeton.edu [Department of Mechanical and Aerospace Engineering, Program in Applied and Computational Mathematics, and Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544-5263 (United States)

2014-05-14T23:59:59.000Z

215

Potential Energy Landscape of the Two-Dimensional XY Model: Higher-Index Stationary Points  

E-Print Network [OSTI]

The application of numerical techniques to the study of energy landscapes of large systems relies on sufficient sampling of the stationary points. Since the number of stationary points is believed to grow exponentially with system size, we can only sample a small fraction. We investigate the interplay between this restricted sample size and the physical features of the potential energy landscape for the two-dimensional $XY$ model in the absence of disorder with up to $N=100$ spins. Using an eigenvector-following technique, we numerically compute stationary points with a given Hessian index $I$ for all possible values of $I$. We investigate the number of stationary points, their energy and index distributions, and other related quantities, with particular focus on the scaling with $N$. The results are used to test a number of conjectures and approximate analytic results for the general properties of energy landscapes.

Dhagash Mehta; Ciaran Hughes; Michael Kastner; David J Wales

2014-12-10T23:59:59.000Z

216

WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA  

E-Print Network [OSTI]

case, the electrons have negative wave energy for 2w ne w wave energy for 2w . > w > 0 nlw/k to the negative wave energy of the electrons. positive

Cary, John R.

2012-01-01T23:59:59.000Z

217

Dispersion relation and Landau damping of waves in high-energy density plasmas  

Science Journals Connector (OSTI)

We present a theoretical investigation on the propagation of electromagnetic waves and electron plasma waves in high energy density plasmas using the covariant Wigner function approach. Based on the covariant Wigner function and Dirac equation, a relativistic quantum kinetic model is established to describe the physical processes in high-energy density plasmas. With the zero-temperature Fermi–Dirac distribution, the dispersion relation and Landau damping of waves containing the relativistic quantum corrected terms are derived. The relativistic quantum corrections to the dispersion relation and Landau damping are analyzed by comparing our results with those obtained in classical and non-relativistic quantum plasmas. We provide a detailed discussion on the Landau damping obtained in classical plasmas, non-relativistic Fermi plasmas and relativistic Fermi plasmas. The contributions of the Bohm potential, the Fermi statistics pressure and relativistic effects to the dispersion relation and Landau damping of waves are quantitatively calculated with real plasma parameters.

Jun Zhu; Peiyong Ji

2012-01-01T23:59:59.000Z

218

Energy-density-functional calculations including the proton-neutron mixing  

E-Print Network [OSTI]

We present results of calculations based on the Skyrme energy density functional including the arbitrary mixing between protons and neutrons. In this framework, single-particle states are superpositions of proton and neutron components and the energy density functional is fully invariant with respect to three-dimensional rotations in the isospin space. The isospin of the system is controlled by means of the isocranking method, which carries over the standard cranking approach to the isospin space. We show numerical results of the isocranking calculations performed for isobaric analogue states in the A=14 and $A=40-56$ nuclei. We also present such results obtained for high-isospin states in $^{48}$Cr, with constraints on the isospin implemented by using the augmented Lagrange method.

Koichi Sato; Jacek Dobaczewski; Takashi Nakatsukasa; Wojciech Satu?a

2013-08-08T23:59:59.000Z

219

Nuclear energy density functionals: what we can learn about/from their global performance?  

E-Print Network [OSTI]

A short review of recent results on the global performance of covariant energy density functionals is presented. It is focused on the analysis of the accuracy of the description of physical observables of ground and excited states as well as to related theoretical uncertainties. In addition, a global analysis of pairing properties is presented and the impact of pairing on the position of two-neutron drip line is discussed.

Afanasjev, A V; Ray, D; Ring, P

2015-01-01T23:59:59.000Z

220

Energy density and volume expansion in solid-liquid phase change, for energy applications.  

E-Print Network [OSTI]

?? Phase change materials (PCMs) have long been studied as thermal energy storage media. However, the Swedish company, Exencotech AB, reaching beyond this usual scope… (more)

Pan, Ruijun

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Maps of the Little Bangs Through Energy Density and Temperature Fluctuations  

E-Print Network [OSTI]

In this letter we propose for the first time to map the heavy-ion collisions at ultra-relativistic energies, similar to the maps of the cosmic microwave background radiation, using fluctuations of energy density and temperature in small phase space bins. We study the evolution of fluctuations at each stage of the collision using an event-by-event hydrodynamic framework. We demonstrate the feasibility of making fluctuation maps from experimental data and its usefulness in extracting considerable information regarding the early stages of the collision and its evolution.

Sumit Basu; Rupa Chatterjee; Basanta K. Nandi; Tapan K. Nayak

2014-05-15T23:59:59.000Z

222

Development of high energy density fuels from mild gasification of coal  

SciTech Connect (OSTI)

The overall objective of the program is the determination of the minimal processing requirements to produce High Energy Density Fuels (HEDF), meeting a minimal energy density of 130,000 Btu/gal (conventional jet fuels have energy densities in the vicinity of 115,000--120,000 Btu/gal) and having acceptable advanced fuel specifications in accordance with the three defined categories of HEDF. The program encompasses assessing current technology capability; selecting acceptable processing and refining schemes; and generating samples of advanced test fuels. A task breakdown structure was developed containing eight key tasks. This report summarizes the work that Amoco Oil Company (AOC), as key subcontractor, performed in the execution of Task 4, Proposed Upgrading Schemes for Advanced Fuel. The intent of the Task 4 study was to represent all the candidate processing options, that were either studied in the experimental efforts of Task 3 or were available from the prior art in the open literature, in a linear program (LP) model. The LP model would allow scaling of the bench-scale Task 3 results to commercial scale and would perform economic evaluations on any combination of the processes which might be used to make HEDF. Section 2.0 of this report summarizes the process and economic bases used. Sections 3.0 and 4.0 details the economics and processing sensitivities for HEDF production. 1 ref., 15 figs., 9 tabs.

Not Available

1990-10-01T23:59:59.000Z

223

Determination of Nuclear Level Densities at an Excitation Energy of 20 MeV  

Science Journals Connector (OSTI)

The level-density ratios in Fe56 and Ni60 at excitation energies of approximately 10 and 20 MeV have been evaluated by combining calculations based on the statistical theory of nuclear reactions and experimental measurements of level widths ? determined from studies of cross-section fluctuations. The importance of each of the various parameters in the statistical-theory calculation was studied as a function of the spin J of the compound nucleus. Assuming a Fermi-gas model with shell and pairing-energy corrections, the evaluated level-density ratios give values of the level density parameter a of 6.-0.9+0.6 and 6.7-1.3+0.8 MeV-1 for Fe56 and Ni60, respectively. These values of a are in excellent agreement with those made at excitation energies of less than 10 MeV. Hence, within the framework of the Fermi-gas model these results give independent evidence, in addition to the evidence already discussed in the literature, that the ? values determined from cross-section-fluctuation measurements are those characteristic of the compound nucleus.

H. K. Vonach and J. R. Huizenga

1965-06-21T23:59:59.000Z

224

On the incorporation of cubic and hexagonal interfacial energy anisotropy in phase field models using higher order tensor terms  

E-Print Network [OSTI]

In this paper, we show how to incorporate cubic and hexagonal anisotropies in interfacial energies in phase field models; this incorporation is achieved by including upto sixth rank tensor terms in the free energy expansion, assuming that the free energy is only a function of coarse grained composition, its gradient, curvature and aberration. We derive the number of non-zero and independent components of these tensors. Further, by demanding that the resultant interfacial energy is positive definite for inclusion of each of the tensor terms individually, we identify the constraints imposed on the independent components of these tensors. The existing results in the invariant group theory literature can be used to simplify the process of construction of some (but not all) of the higher order tensors. Finally, we derive the relevant phase field evolution equations.

E. S. Nani; M. P. Gururajan

2014-04-03T23:59:59.000Z

225

Solar Thermal Energy Storage Device: Hybrid Nanostructures for High-Energy-Density Solar Thermal Fuels  

SciTech Connect (OSTI)

HEATS Project: MIT is developing a thermal energy storage device that captures energy from the sun; this energy can be stored and released at a later time when it is needed most. Within the device, the absorption of sunlight causes the solar thermal fuel’s photoactive molecules to change shape, which allows energy to be stored within their chemical bonds. A trigger is applied to release the stored energy as heat, where it can be converted into electricity or used directly as heat. The molecules would then revert to their original shape, and can be recharged using sunlight to begin the process anew. MIT’s technology would be 100% renewable, rechargeable like a battery, and emissions-free. Devices using these solar thermal fuels—called Hybrisol—can also be used without a grid infrastructure for applications such as de-icing, heating, cooking, and water purification.

None

2012-01-09T23:59:59.000Z

226

Higher energy electronic transitions of HC2n+1H+ ,,n=27... and HC2n+1H  

E-Print Network [OSTI]

Higher energy electronic transitions of HC2n+1H+ ,,n=2­7... and HC2n+1H ,,n=4­7... in neon matrices to other carbon chains. The B~ 3 u - X~ 3 g - transition in the UV of neutral HC2n+1H n=4­7 has also been, they are perhaps building blocks of larger organic sys- tems such as polycyclic aromatic hydrocarbons. CnH,4­7 Cn

Maier, John Paul

227

Measurements of the Electron Cloud Density in the PEP-II Low Energy Ring  

SciTech Connect (OSTI)

Clouds of low energy electronsin the vacuum beam pipes of accelerators of positively charged particle beams present a serious limitation for operation of these machines at high currents. Because of the size of these accelerators, it is difficult to probe the low energyelectron clouds over substantial lengths of the beam pipe. We have developed a novel technique to directly measure the electron cloud density via the phase shift induced in a TE wave that is independently excited and transmitted over a section of the accelerator. We infer the absolute phase shift with relatively high accuracy from the phase modulation of the transmission due to the modulation of the electron cloud density from a gap in the positively charged beam. We have used this technique for the first time to measure the average electron cloud density over a 50 m straight section in the positron ring of the PEP-II collider at the Stanford Linear Accelerator Center. We have also measured the variation of the density by using low field solenoid magnets to control the electrons.

Byrd, John; De Santis, Stefano; Sonnad, Kiran; Caspers, Fritz; Kroyer, Tom; Krasnykh, Anatoly; Pivi, Mauro

2008-06-01T23:59:59.000Z

228

The slowly varying density approximation for the surface tension and surface energy of  

Science Journals Connector (OSTI)

We present a detailed study of the validity of the slowly varying density approximation to calculate the surface tension and the surface energy of Lennard-Jones fluids. To do so, we consider three explicit analytical expressions for the radial distribution function of the liquid phase, including one proposed by our research group, together with very accurate expressions for the liquid and vapour densities, also proposed by ourselves. The calculation of the surface tension from the direct correlation function using the Percus–Yevick and the hypernetted-chain approximations is also considered. Finally, our results are compared with those obtained by other authors by computer simulation, and also with those estimated via the general expressions (i.e., not in the ambit of the approximation studied here). We demonstrate that although the slowly varying density approximation is in good agreement with more complex expressions near the critical point, it is not adequate to calculate the surface energy and the surface tension of Lennard-Jones fluids at every temperature.

A Mulero; C Galán; F Cuadros

2003-01-01T23:59:59.000Z

229

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

230

Schlieren technique applied to the arc temperature measurement in a high energy density cutting torch  

SciTech Connect (OSTI)

Plasma temperature and radial density profiles of the plasma species in a high energy density cutting arc have been obtained by using a quantitative schlieren technique. A Z-type two-mirror schlieren system was used in this research. Due to its great sensibility such technique allows measuring plasma composition and temperature from the arc axis to the surrounding medium by processing the gray-level contrast values of digital schlieren images recorded at the observation plane for a given position of a transverse knife located at the exit focal plane of the system. The technique has provided a good visualization of the plasma flow emerging from the nozzle and its interactions with the surrounding medium and the anode. The obtained temperature values are in good agreement with those values previously obtained by the authors on the same torch using Langmuir probes.

Prevosto, L.; Mancinelli, B. [Departamento Ing. Electromecanica, Grupo de Descargas Electricas, Universidad Tecnologica Nacional, Regional Venado Tuerto, Las Heras 644, Venado Tuerto, Santa Fe 2600 (Argentina); Artana, G. [Departamento Ing. Mecanica, Laboratorio de Fluidodinamica, Facultad de Ingenieria (UBA), Paseo Colon 850 (C1063ACV), Buenos Aires (Argentina); Kelly, H. [Departamento de Fisica, Instituto de Fisica del Plasma (CONICET), Facultad de Ciencias Exactas y Naturales (UBA), Ciudad Universitaria Pab. I, Buenos Aires 1428 (Argentina)

2010-01-15T23:59:59.000Z

231

Inertial Confinement Fusion, High Energy Density Plasmas and an Energy Source on Earth  

E-Print Network [OSTI]

Driver Laser h=5-10% Heavy ion Accelerator h=15-40% Z-pinch h~15% Ignition by stagnation of convergent good progress toward achieving fusion ignition and high gain for energy applications We are making good progress toward achievingWe are making good progress toward achieving fusion ignition and high gain

232

Linear Relationship Between Weighted-Average Madelung and Density Functional Theory Energies for MgO Nanotubes  

E-Print Network [OSTI]

Energies for MgO Nanotubes Journal: The Journal of Physical Chemistry Manuscript ID: jp-2012-08041d.R1 Constants and Density Functional Theory Energies for MgO Nanotubes Mark D. Baker,*1 A. David Baker2 , Jane-average Madelung constants of MgO nanotubes correlate in an essentially perfectly linear way with cohesive energies

Hanusa, Christopher

233

Condition on the KohnSham kinetic energy and modern parametrization of the ThomasFermi density  

E-Print Network [OSTI]

; published online 20 January 2009 We study the asymptotic expansion of the neutral-atom energy as the atomic-correlation energy, EXC n , must be approximated. But a direct, orbital-free DFT could be constructed if onlyCondition on the Kohn­Sham kinetic energy and modern parametrization of the Thomas­Fermi density

Burke, Kieron

234

Breast Density Assessment in Adolescent Girls Using Dual-Energy X-ray Absorptiometry: A Feasibility Study  

Science Journals Connector (OSTI)

...Assessment in Adolescent Girls Using Dual-Energy X-ray Absorptiometry: A Feasibility...explored a commercially available dual-energy X-ray absorptiometer (DXA) system...Prev 2008;17(7):1709-13) Dual-energy X-ray Absorptiometry|breast density...

John A. Shepherd; Serghei Malkov; Bo Fan; Aurelie Laidevant; Rachel Novotny; Gertraud Maskarinec

2008-07-01T23:59:59.000Z

235

Transverse exchange energy in relativistic density-functional calculations: An alternative approximation  

Science Journals Connector (OSTI)

The large error of the local-density approximation for the transverse photon-electron or Breit interaction is analyzed, transforming the Breit interaction into a sum of terms suitable to be handled in a nonrelativistic formalism: the local approximation for each of these terms is built up and an alternative expression for the relativistic exchange energy is proposed. Calculations using this expression are made for atoms ranging throughout the periodic table and the results show a sharp improvement when compared to those obtained by the previous approximation.

Mauro Boero and Pietro Cortona

1994-02-01T23:59:59.000Z

236

Generation of high-energy-density ion bunches by ultraintense laser-cone-target interaction  

SciTech Connect (OSTI)

A scheme in which carbon ion bunches are accelerated to a high energy and density by a laser pulse (?10{sup 21}?W/cm{sup 2}) irradiating cone targets is proposed and investigated using particle-in-cell simulations. The laser pulse is focused by the cone and drives forward an ultrathin foil located at the cone's tip. In the course of the work, best results were obtained employing target configurations combining a low-Z cone with a multispecies foil transversely shaped to match the laser intensity profile.

Yang, X. H.; Zhuo, H. B., E-mail: hongbin.zhuo@gmail.com; Ma, Y. Y.; Zou, D. B.; Yu, T. P.; Ge, Z. Y.; Yin, Y.; Shao, F. Q. [College of Science, National University of Defense Technology, Changsha 410073 (China); Yu, W. [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Xu, H., E-mail: xuhanemail@gmail.com [State Key Laboratory of High Performance Computing, National University of Defense Technology, Changsha 410073 (China); Borghesi, M., E-mail: m.borghesi@qub.ac.uk [School of Mathematics and Physics, Queen's University of Belfast, Belfast BT7 1NN (United Kingdom); Institute of Physics of the ASCR, ELI-Beamlines Project, Na Slovance 2, 18221 Prague (Czech Republic)

2014-06-15T23:59:59.000Z

237

Magnetized Bianchi Type $VI_{0}$ Barotropic Massive String Universe with Decaying Vacuum Energy Density $?$  

E-Print Network [OSTI]

Bianchi type $VI_{0}$ massive string cosmological models using the technique given by Letelier (1983) with magnetic field are investigated. To get the deterministic models, we assume that the expansion ($\\theta$) in the model is proportional to the shear ($\\sigma$) and also the fluid obeys the barotropic equation of state. It was found that vacuum energy density $\\Lambda \\propto \\frac{1}{t^{2}}$ which matches with natural units. The behaviour of the models from physical and geometrical aspects in presence and absence of magnetic field is also discussed.

Anirudh Pradhan; Raj Bali

2008-05-22T23:59:59.000Z

238

High-energy-density physics experiments with intense heavy ion beams  

Science Journals Connector (OSTI)

In this paper we discuss physical and technical issues of high-energy-density physics (HEDP) experiments with intense heavy ion beams that are being performed at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt. Special attention is given to a comparison of some recent results on expansion dynamics of evaporating lead that have been obtained in heavy ion beam driven HIHEX (Heavy-Ion Heating and Expansion) experiments at GSI-Darmstadt and in high-explosive driven shock wave loading and release experiments at IPCP–Chernogolovka.

D. Varentsov; V. Ya. Ternovoi; M. Kulish; D. Fernengel; A. Fertman; A. Hug; J. Menzel; P. Ni; D.N. Nikolaev; N. Shilkin; V. Turtikov; S. Udrea; V.E. Fortov; A.A. Golubev; V.K. Gryaznov; D.H.H. Hoffmann; V. Kim; I.V. Lomonosov; V. Mintsev; B.Yu. Sharkov; A. Shutov; P. Spiller; N.A. Tahir; H. Wahl

2007-01-01T23:59:59.000Z

239

Mean-Field Calculation Based on Proton-Neutron Mixed Energy Density Functionals  

E-Print Network [OSTI]

We have performed calculations based on the Skyrme energy density functional (EDF) that includes arbitrary mixing between protons and neutrons. In this framework, single-particle states are generalized as mixtures of proton and neutron components. The model assumes that the Skyrme EDF is invariant under the rotation in isospin space and the Coulomb force is the only source of the isospin symmetry breaking. To control the isospin of the system, we employ the isocranking method, which is analogous to the standard cranking approach used for describing high-spin states. Here, we present results of the isocranking calculations performed for the isobaric analog states in $A = 40$ and $A = 54$ nuclei.

Koichi Sato; Jacek Dobaczewski; Takashi Nakatsukasa; Wojciech Satu?a

2014-10-10T23:59:59.000Z

240

Mean-Field Calculation Based on Proton-Neutron Mixed Energy Density Functionals  

E-Print Network [OSTI]

We have performed calculations based on the Skyrme energy density functional (EDF) that includes arbitrary mixing between protons and neutrons. In this framework, single-particle states are generalized as mixtures of proton and neutron components. The model assumes that the Skyrme EDF is invariant under the rotation in isospin space and the Coulomb force is the only source of the isospin symmetry breaking. To control the isospin of the system, we employ the isocranking method, which is analogous to the standard cranking approach used for describing high-spin states. Here, we present results of the isocranking calculations performed for the isobaric analog states in $A = 40$ and $A = 54$ nuclei.

Sato, Koichi; Nakatsukasa, Takashi; Satu?a, Wojciech

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Beam energy distribution influences on density modulation efficiency in seeded free-electron lasers  

E-Print Network [OSTI]

The beam energy spread at the entrance of undulator system is of paramount importance for efficient density modulation in high-gain seeded free-electron lasers (FELs). In this paper, the dependences of high harmonic micro-bunching in the high-gain harmonic generation (HGHG), echo-enabled harmonic generation (EEHG) and phase-merging enhanced harmonic generation (PEHG) schemes on the electron energy spread distribution are studied. Theoretical investigations and multi-dimensional numerical simulations are applied to the cases of uniform and saddle beam energy distributions and compared to a traditional Gaussian distribution. It shows that the uniform and saddle electron energy distributions significantly enhance the performance of HGHG-FELs, while they almost have no influence on EEHG and PEHG schemes. A numerical example demonstrates that, with about 84keV RMS uniform and/or saddle slice energy spread, the 30th harmonic radiation can be directly generated by a single-stage seeding scheme for a soft x-ray FEL f...

Wang, Guanglei; Deng, Haixiao; Zhang, Weiqing; Wu, Guorong; Dai, Dongxu; Wang, Dong; Zhao, Zhentang; Yang, Xueming

2015-01-01T23:59:59.000Z

242

Nuclear level densities below 40 MeV excitation energy in the mass regionA ? 50  

Science Journals Connector (OSTI)

Consistent pre-equilibrium emission and statistical model calculations of fast neutron induced reaction cross sections are used to validate nuclear level densities for excitation energies up to 40 MeV in the mass...

M. Avrigeanu; M. Iva?cu; V. Avrigeanu

1990-01-01T23:59:59.000Z

243

Strongly Dipolar Polythiourea and Polyurea Dielectrics with High Electrical Breakdown, Low Loss, and High Electrical Energy Density  

Science Journals Connector (OSTI)

Dielectric materials with high electric energy density and low loss are of great importance for applications in modern electronics and electrical systems. Strongly dipolar materials have the potential ... polymer...

Shan Wu; Quinn Burlingame; Zhao-Xi Cheng; Minren Lin…

2014-12-01T23:59:59.000Z

244

Density dependence of the nuclear symmetry energy from measurements of neutron radii in nuclei  

SciTech Connect (OSTI)

We study the density dependence of the nuclear symmetry energy, characterized by its slope parameter L, by means of the information provided by the neutron radius and the neutron skin thickness in finite nuclei. These quantities are extracted from the analysis of data obtained in antiprotonic atoms, from the parity-violating asymmetry at low-momentum transfer in polarized electron scattering in {sup 208}Pb, and from the electric dipole polarizability obtained via polarized proton inelastic scattering at forward angles in {sup 208}Pb. All these experiments provide different constraints on the slope L of the symmetry energy but the corresponding values have a considerable overlap in a range around 50 MeV ? L ? 70 MeV, in a reasonable agreement with other estimates that use different observables and methods to extract L.

Viñas, X.; Centelles, M. [Departament d'Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos, Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain); Roca-Maza, X. [Dipartimento di Fisica, Università degli Studi di Milano and INFN, Sezione di Milano, I-20133 Milano (Italy); Warda, M. [Katedra Fizyki Teoretycznej, Uniwersytet Marii Curie–Sk?odowskiej ul. Radziszewskiego 10, 20-031 Lublin (Poland)

2014-07-23T23:59:59.000Z

245

Vacuum energy densities of a field in a cavity with a mobile boundary  

E-Print Network [OSTI]

We consider the zero-point field fluctuations, and the related field energy densities, inside a one-dimensional and a three-dimensional cavity with a mobile wall. The mechanical degrees of freedom of the mobile wall are described quantum mechanically and they are fully included in the overall system dynamics. In this optomechanical system, the field and the wall can interact with each other through the radiation pressure on the wall, given by the photons inside the cavity or even by vacuum fluctuations. We consider two cases: the one-dimensional electromagnetic field and the three-dimensional scalar field, and use the Green's functions formalism, which allows extension of the results obtained for the scalar field to the electromagnetic field. We show that the quantum fluctuations of the position of the cavity's mobile wall significantly affect the field energy density inside the cavity, in particular at the very proximity of the mobile wall. The dependence of this effect from the ultraviolet cutoff frequency, related to the plasma frequency of the cavity walls, is discussed. We also compare our new results for the one-dimensional electromagnetic field and the three-dimensional massless scalar field to results recently obtained for the one-dimensional massless scalar field. We show that the presence of a mobile wall also changes the Casimir-Polder force on a polarizable body placed inside the cavity, giving the possibility to detect experimentally the new effects we have considered.

Federico Armata; Roberto Passante

2015-01-15T23:59:59.000Z

246

Vacuum Energy Densities of a Field in a Cavity with a Mobile Boundary  

E-Print Network [OSTI]

We consider the zero-point field fluctuations, and the related field energy densities, inside a one-dimensional and a three-dimensional cavity with a mobile wall. The mechanical degrees of freedom of the mobile wall are described quantum-mechanically and they are fully included in the overall system dynamics. In this optomechanical system, the field and the wall can interact with each other through the radiation pressure on the wall, given by the photons inside the cavity or even by vacuum fluctuations. We consider two cases: the 1D electromagnetic field and the 3D scalar field, and use the Green's functions formalism, that allows extension of the results obtained for the scalar field to the electromagnetic field. We show that the quantum fluctuations of the position of the cavity's mobile wall significantly affect the field energy density inside the cavity, in particular at the very proximity of the mobile wall. The dependence of this effect from the ultraviolet cut-off frequency, related to the plasma frequency of the cavity walls, is discussed. We also compare our new results for the 1D electromagnetic field and the 3D massless scalar field to results recently obtained for the 1D massless scalar field. We show that the presence of a mobile wall also changes the Casimir-Polder force on a polarizable body placed inside the cavity, giving possibility to detect experimentally the new effects we have considered.

Federico Armata; Roberto Passante

2014-11-19T23:59:59.000Z

247

Vacuum Energy Densities of a Field in a Cavity with a Mobile Boundary  

E-Print Network [OSTI]

We consider the zero-point field fluctuations, and the related field energy densities, inside a one-dimensional and a three-dimensional cavity with a mobile wall. The mechanical degrees of freedom of the mobile wall are described quantum-mechanically and they are fully included in the overall system dynamics. In this optomechanical system, the field and the wall can interact with each other through the radiation pressure on the wall, given by the photons inside the cavity or even by vacuum fluctuations. We consider two cases: the 1D electromagnetic field and the 3D scalar field, and use the Green's functions formalism, that allows extension of the results obtained for the scalar field to the electromagnetic field. We show that the quantum fluctuations of the position of the cavity's mobile wall significantly affect the field energy density inside the cavity, in particular at the very proximity of the mobile wall. The dependence of this effect from the ultraviolet cut-off frequency, related to the plasma frequ...

Armata, Federico

2014-01-01T23:59:59.000Z

248

Constraining the gravitational wave energy density of the Universe using Earth's ring  

E-Print Network [OSTI]

The search for gravitational waves is one of today's major scientific endeavors. A gravitational wave can interact with matter by exciting vibrations of elastic bodies. Earth itself is a large elastic body whose so-called normal-mode oscillations ring up when a gravitational wave passes. Therefore, precise measurement of vibration amplitudes can be used to search for the elusive gravitational-wave signals. Earth's free oscillations that can be observed after high-magnitude earthquakes have been studied extensively with gravimeters and low-frequency seismometers over many decades leading to invaluable insight into Earth's structure. Making use of our detailed understanding of Earth's normal modes, numerical models are employed for the first time to accurately calculate Earth's gravitational-wave response, and thereby turn a network of sensors that so far has served to improve our understanding of Earth, into an astrophysical observatory exploring our Universe. In this article, we constrain the energy density of gravitational waves to values in the range 0.035 - 0.15 normalized by the critical energy density of the Universe at frequencies between 0.3mHz and 5mHz, using 10 years of data from the gravimeter network of the Global Geodynamics Project that continuously monitors Earth's oscillations. This work is the first step towards a systematic investigation of the sensitivity of gravimeter networks to gravitational waves. Further advance in gravimeter technology could improve sensitivity of these networks and possibly lead to gravitational-wave detection.

Michael Coughlin; Jan Harms

2014-06-04T23:59:59.000Z

249

Isospin-invariant Skyrme energy-density-functional approach with axial symmetry  

E-Print Network [OSTI]

We develop the isospin-invariant Skyrme-EDF method by considering local densities in all possible isospin channels and proton-neutron (p-n) mixing terms as mandated by the isospin symmetry. The EDF employed has the most general form that depends quadratically on the isoscalar and isovector densities. We test and benchmark the resulting p-n EDF approach, and study the general properties of the new scheme by means of the cranking in the isospin space. We extend the existing axial DFT solver HFBTHO to the case of isospin-invariant EDF approach with all possible p-n mixing terms. Explicit expressions have been derived for all the densities and potentials that appear in the isospin representation. In practical tests, we consider the Skyrme EDF SkM* and, as a first application, concentrate on Hartree-Fock aspects of the problem, i.e., pairing has been disregarded. Calculations have been performed for the (A=78, T~11), (A=40, T~8), and (A=48, T~4) isobaric analog chains. Isospin structure of self-consistent p-n mixed solutions has been investigated with and without the Coulomb interaction, which is the sole source of isospin symmetry breaking in our approach. The extended axial HFBTHO solver has been benchmarked against the symmetry-unrestricted HFODD code for deformed and spherical states. We developed and tested a general isospin-invariant Skyrme-EDF framework. The new approach permits spin-isospin densities that may give rise to, hitherto, unexplored modes in the excitation spectrum. The new formalism has been tested in the Hartree-Fock limit. A systematic comparison between HFODD and HFBTHO results show a maximum deviation of about 10 keV on the total binding energy for deformed nuclei when the Coulomb term is included. Without this term, the results of both solvers agree down to a ~10 eV level.

J. A. Sheikh; N. Hinohara; J. Dobaczewski; T. Nakatsukasa; W. Nazarewicz; K. Sato

2014-05-20T23:59:59.000Z

250

Kinetic and electron-electron energies for convex sums of ground state densities with degeneracies and fractional electron number  

SciTech Connect (OSTI)

Properties of exact density functionals provide useful constraints for the development of new approximate functionals. This paper focuses on convex sums of ground-level densities. It is observed that the electronic kinetic energy of a convex sum of degenerate ground-level densities is equal to the convex sum of the kinetic energies of the individual degenerate densities. (The same type of relationship holds also for the electron-electron repulsion energy.) This extends a known property of the Levy-Valone Ensemble Constrained-Search and the Lieb Legendre-Transform refomulations of the Hohenberg-Kohn functional to the individual components of the functional. Moreover, we observe that the kinetic and electron-repulsion results also apply to densities with fractional electron number (even if there are no degeneracies), and we close with an analogous point-wise property involving the external potential. Examples where different degenerate states have different kinetic energy and electron-nuclear attraction energy are given; consequently, individual components of the ground state electronic energy can change abruptly when the molecular geometry changes. These discontinuities are predicted to be ubiquitous at conical intersections, complicating the development of universally applicable density-functional approximations.

Levy, Mel, E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States) [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States); Department of Physics, North Carolina A and T State University, Greensboro, North Carolina 27411 (United States); Department of Chemistry, Tulane University, New Orleans, Louisiana 70118 (United States); Anderson, James S. M.; Zadeh, Farnaz Heidar; Ayers, Paul W., E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario (Canada)

2014-05-14T23:59:59.000Z

251

High Energy Density Na-S/NiCl2 Hybrid Battery  

SciTech Connect (OSTI)

High temperature (250-350°C) sodium-beta alumina batteries (NBBs) are attractive energy storage devices for renewable energy integration and other grid related applications. Currently, two technologies are commercially available in NBBs, e.g., sodium-sulfur (Na-S) battery and sodium-metal halide (ZEBRA) batteries. In this study, we investigated the combination of these two chemistries with a mixed cathode. In particular, the cathode of the cell consisted of molten NaAlCl4 as a catholyte and a mixture of Ni, NaCl and Na2S as active materials. During cycling, two reversible plateaus were observed in cell voltage profiles, which matched electrochemical reactions for Na-S and Na-NiCl2 redox couples. An irreversible reaction between sulfur species and Ni was identified during initial charge at 280°C, which caused a decrease in cell capacity. The final products on discharge included Na2Sn with 1< n < 3, which differed from Na2S3 found in traditional Na-S battery. Reduction of sulfur in the mixed cathode led to an increase in overall energy density over ZEBRA batteries. Despite of the initial drop in cell capacity, the mixed cathode demonstrated relatively stable cycling with more than 95% of capacity retained over 60 cycles under 10mA/cm2. Optimization of the cathode may lead to further improvements in battery performance.

Lu, Xiaochuan; Lemmon, John P.; Kim, Jin Yong; Sprenkle, Vincent L.; Yang, Zhenguo (Gary) [Gary

2013-02-15T23:59:59.000Z

252

Holographic energy density on Ho\\v{r}ava-Lifshitz cosmology  

E-Print Network [OSTI]

In Ho\\v{r}ava-Lifshitz cosmology we use the holographic Ricci-like cut-off for the energy density proposed by L. N. Granda and A. Oliveros and under this framework we study, through the cosmic evolution at late times, the sign change in the amount of non-conservation energy ($Q$) present in this cosmology. We revise the early stage (curvature-dependent) of this cosmology, where a term reminiscent of stiff matter is the dominant, and in this stage we find a power-law solution for the cosmic scale factor although $\\omega =-1$. Late and early phantom schemes are obtained without requiring $\\omega <-1$. Nevertheless, these schemes are not feasible according to what is shown in this paper. We also show that $ \\omega =-1$ alone does not imply a de Sitter phase in the present cosmology. Thermal aspects are revised by considering the energy interchange between the bulk and the spacetime boundary and we conclude that there is no thermal equilibrium between them. Finally, a ghost scalar graviton (extra degree of fre...

Lepe, Samuel; Torres, Francisco

2015-01-01T23:59:59.000Z

253

Symmetry energy effects on the mixed hadron-quark phase at high baryon density  

SciTech Connect (OSTI)

The phase transition of hadronic to quark matter at high baryon and isospin density is analyzed. Relativistic mean-field models are used to describe hadronic matter, and the MIT bag model is adopted for quark matter. The boundaries of the mixed phase and the related critical points for symmetric and asymmetric matter are obtained. Due to the different symmetry term in the two phases, isospin effects appear to be rather significant. With increasing isospin asymmetry the binodal transition line of the (T,{rho}{sub B}) diagram is lowered to a region accessible through heavy-ion collisions in the energy range of the new planned facilities (e.g., the FAIR/NICA projects). Some observable effects are suggested, in particular an isospin distillation mechanism with a more isospin asymmetric quark phase, to be seen in charged meson yield ratios, and an onset of quark number scaling of the meson-baryon elliptic flows. The presented isospin effects on the mixed phase appear to be robust with respect to even large variations of the poorly known symmetry term at high baryon density in the hadron phase. The dependence of the results on a suitable treatment of isospin contributions in effective QCD Lagrangian approaches, at the level of explicit isovector parts and/or quark condensates, is discussed.

Di Toro, M.; Greco, V.; Plumari, S. [Laboratori Nazionali del Sud INFN, I-95123 Catania (Italy); Pysics and Astronomy Department, University of Catania (Italy); Liu, B. [IHEP, Chinese Academy of Sciences, Beijing (China); Theoretical Physics Center for Scientific Facilities, Chinese Academy of Sciences, 100049 Beijing (China); Baran, V. [Pysics Faculty, University of Bucharest and NIPNE-HH (Romania); Colonna, M. [Laboratori Nazionali del Sud INFN, I-95123 Catania (Italy)

2011-01-15T23:59:59.000Z

254

Thermodynamics of baryonic matter with strangeness within non-relativistic energy density functional model  

E-Print Network [OSTI]

We study the thermodynamical properties of compressed baryonic matter with strangeness within non-relativistic energy density functional models with a particular emphasis on possible phase transitions found earlier for a simple $n,p,e,\\Lambda$-mixture. The aim of the paper is twofold: I) examining the phase structure of the complete system, including the full baryonic octet and II) testing the sensitivity of the results to the model parameters. We find that, associated to the onset of the different hyperonic families, up to three separate strangeness-driven phase transitions may occur. Consequently, a large fraction of the baryonic density domain is covered by phase coexistence with potential relevance for (proto)-neutron star evolution. It is shown that the presence of a phase transition is compatible both with the observational constraint on the maximal neutron star mass, and with the present experimental information on hypernuclei. In particular we show that two solar mass neutron stars are compatible with important hyperon content. Still, the parameter space is too large to give a definitive conclusion of the possible occurrence of a strangeness driven phase transition, and further constraints from multiple-hyperon nuclei and/or hyperon diffusion data are needed.

Ad. R. Raduta; F. Gulminelli; M. Oertel

2014-06-02T23:59:59.000Z

255

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

256

Constraining the gravitational wave energy density of the Universe using Earth's ring  

E-Print Network [OSTI]

The search for gravitational waves is one of today's major scientific endeavors. A gravitational wave can interact with matter by exciting vibrations of elastic bodies. Earth itself is a large elastic body whose so-called normal-mode oscillations ring up when a gravitational wave passes. Therefore, precise measurement of vibration amplitudes can be used to search for the elusive gravitational-wave signals. Earth's free oscillations that can be observed after high-magnitude earthquakes have been studied extensively with gravimeters and low-frequency seismometers over many decades leading to invaluable insight into Earth's structure. Making use of our detailed understanding of Earth's normal modes, numerical models are employed for the first time to accurately calculate Earth's gravitational-wave response, and thereby turn a network of sensors that so far has served to improve our understanding of Earth, into an astrophysical observatory exploring our Universe. In this article, we constrain the energy density o...

Coughlin, Michael

2014-01-01T23:59:59.000Z

257

Equation-of-state properties of high-energy-density matter using intense heavy ion beams with an annular focal spot  

Science Journals Connector (OSTI)

This paper presents two-dimensional numerical simulations of the hydrodynamic response of solid as well as hollow cylindrical targets made of lead that are irradiated by an intense beam of uranium ions which has an annular focal spot. Using a particle tracking computer code, it has been shown that a plasma lens can generate such a beam with parameters used in the calculations presented in this paper. The total number of particles in the beam is 2×1011 and the particle energy is about 200 MeV/u that means a total energy of approximately 1.5 kJ. This energy is delivered in a pulse that is 50 ns long. These beam parameters lead to a specific energy deposition of 50–100 kJ/g and a specific power deposition of 1–2 TW/g in solid matter. These calculations show that in case of the solid lead cylinder, it may be possible to achieve more than 4 times solid lead density along the cylinder axis at the time of maximum compression. The pressure in the compressed region is about 20 Mbar and the temperature is a few eV. In the case of a hollow cylinder, one also achieves the same degree of compression but now the temperature in the compressed region is much higher (over 10 eV). Such samples of highly compressed matter can be used to study the equation-of-state properties of high-energy-density matter. It is expected that by the end of the year 2001, after completion of the upgrade of the existing facilities, the above beam parameters will be available at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt. This will open up the possibility to carry out very interesting experiments on a number of important problems including the investigation of the EOS of high-energy-density matter.

N. A. Tahir, D. H. H. Hoffmann, A. Kozyreva, A. Shutov, J. A. Maruhn, U. Neuner, A. Tauschwitz, P. Spiller, and R. Bock

2000-07-01T23:59:59.000Z

258

Applications of Skyrme energy-density functional to fusion reactions for synthesis of superheavy nuclei  

SciTech Connect (OSTI)

The Skyrme energy-density functional approach has been extended to study massive heavy-ion fusion reactions. Based on the potential barrier obtained and the parametrized barrier distribution the fusion (capture) excitation functions of a lot of heavy-ion fusion reactions are studied systematically. The average deviations of fusion cross sections at energies near and above the barriers from experimental data are less than 0.05 for 92% of 76 fusion reactions with Z{sub 1}Z{sub 2}<1200. For the massive fusion reactions, for example, the {sup 238}U-induced reactions and {sup 48}Ca+{sup 208}Pb, the capture excitation functions have been reproduced remarkably well. The influence of structure effects in the reaction partners on the capture cross sections is studied with our parametrized barrier distribution. By comparing the reactions induced by double-magic nucleus {sup 48}Ca and by {sup 32}S and {sup 35}Cl, the ''threshold-like'' behavior in the capture excitation function for {sup 48}Ca-induced reactions is explored and an optimal balance between the capture cross section and the excitation energy of the compound nucleus is studied. Finally, the fusion reactions with {sup 36}S, {sup 37}Cl, {sup 48}Ca, and {sup 50}Ti bombarding {sup 248}Cm, {sup 247,249}Bk, {sup 250,252,254}Cf, and {sup 252,254}Es, as well as the reactions leading to the same compound nucleus with Z=120 and N=182, are studied further. The calculation results for these reactions are useful for searching for the optimal fusion configuration and suitable incident energy in the synthesis of superheavy nuclei.

Wang Ning; Scheid, Werner [Institute for Theoretical Physics at Justus-Liebig-University, D-35392 Giessen (Germany); Wu Xizhen; Liu Min [China Institute of Atomic Energy, Beijing 102413 (China); Li Zhuxia [China Institute of Atomic Energy, Beijing 102413 (China); Institute of Theoretical Physics, Chinese Academic of Science, Beijing 100080 (China); Nuclear Theory Center of National Laboratory of Heavy Ion Accelerator, Lanzhou 730000 (China)

2006-10-15T23:59:59.000Z

259

The Potential for Pennsylvania Crops as Biofuels Higher energy costs over the past few years have created opportunities for the use of crops and crop residues  

E-Print Network [OSTI]

The Potential for Pennsylvania Crops as Biofuels Higher energy costs over the past few years have Potential for Pennsylvania Crops as Biofuels 2 Soybeans Soybean acreage is on the increase in Pennsylvania

Lee, Dongwon

260

Building a Universal Nuclear Energy Density Functional (UNEDF): SciDAC-2 Project  

SciTech Connect (OSTI)

An understanding of the properties of atomic nuclei is crucial for a complete nuclear theory, for element formation, for properties of stars, and for present and future energy and defense applications. During the period of Dec. 1, 2006 - Jun. 30, 2012, the UNEDF collaboration carried out a comprehensive study of all nuclei based on the most accurate knowledge of the strong nuclear interaction, the most reliable theoretical approaches, the most advanced algorithms, and extensive computational resources, with a view towards scaling to the petaflop platforms and beyond. The long-term vision initiated with UNEDF is to arrive at a comprehensive, quantitative, and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. We seek to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties. Specifically, the mission of this project has been three-fold: first, to find an optimal energy density functional (EDF) using all our knowledge of the nucleonic Hamiltonian and basic nuclear properties; second, to apply the EDF theory and its extensions to validate the functional using all the available relevant nuclear structure and reaction data; and third, to apply the validated theory to properties of interest that cannot be measured, in particular the properties needed for reaction theory.

Carlson, Joe; Furnstahl, Dick; Lusk, Rusty; Nazarewicz, Witek; Ng, Esmond; Thompson, Ian; Vary, James

2012-06-30T23:59:59.000Z

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261

Microscopic description of fission in Uranium isotopes with the Gogny energy density functional  

E-Print Network [OSTI]

The most recent parametrizations D1S, D1N and D1M of the Gogny energy density functional are used to describe fission in the isotopes $^{232-280}$ U. Fission paths, collective masses and zero point quantum corrections, obtained within the constrained Hartree-Fock-Bogoliubov approximation, are used to compute the systematics of the spontaneous fission half-lives $t_\\mathrm{SF}$, the masses and charges of the fission fragments as well as their intrinsic shapes. The Gogny-D1M parametrization has been benchmarked against available experimental data on inner and second barrier heights, excitation energies of the fission isomers and half-lives in a selected set of Pu, Cm, Cf, Fm, No, Rf, Sg, Hs and Fl nuclei. It is concluded that D1M represents a reasonable starting point to describe fission in heavy and superheavy nuclei. Special attention is also paid to understand the uncertainties in the predicted $t_\\mathrm{SF}$ values arising from the different building blocks entering the standard semi-classical Wentzel-Kramers-Brillouin formula. Although the uncertainties are large, the trend with mass or neutron numbers are well reproduced and therefore the theory still has predictive power. In this respect, it is also shown that modifications of a few per cent in the pairing strength can have a significant impact on the collective masses leading to uncertainties in the $t_\\mathrm{SF}$ values of several orders of magnitude.

R. Rodriguez-Guzman; L. M. Robledo

2014-05-25T23:59:59.000Z

262

3-D Density Model Of Mt Etna Volcano (Southern Italy) | Open Energy  

Open Energy Info (EERE)

3-D Density Model Of Mt Etna Volcano (Southern Italy) 3-D Density Model Of Mt Etna Volcano (Southern Italy) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: 3-D Density Model Of Mt Etna Volcano (Southern Italy) Details Activities (0) Areas (0) Regions (0) Abstract: A detailed density model of Mt. Etna and its surrounding areas has been evaluated using a 3-D inversion of the gravimetric data acquired in the 1980's. Several high-density and low-density bodies are found, penetrating from shallow depths as far down as 12 km bsl. A positive correlation (in terms of location, extent, density, and velocity) is established between several anomalies of the density model and features identified in previously published seismic tomographies. A prominent high-density body extending down to 7 km bsl is recognized in the southern

263

Thermal heat radiation, near-field energy density and near-field radiative heat transfer of coated materials  

E-Print Network [OSTI]

We investigate the thermal radiation and thermal near-field energy density of a metal-coated semi-infinite body for different substrates. We show that the surface polariton coupling within the metal coating leads to an enhancement of the TM-mode part of the thermal near-field energy density when a polar substrate is used. In this case the result obtained for a free standing metal film is retrieved. In contrast, in the case of a metal substrate there is no enhancement in the TM-mode part, as can also be explained within the framework of surface plasmon coupling within the coating. Finally, we discuss the influence of the enhanced thermal energy density on the near-field radiative heat transfer between a simple semi-infinite and a coated semi-infinite body for different material combinations.

Svend-Age Biehs

2011-03-15T23:59:59.000Z

264

Mechanical confinement for improved energy storage density in BNT-BT-KNN lead-free ceramic capacitors  

SciTech Connect (OSTI)

With the advent of modern power electronics, embedded circuits and non-conventional energy harvesting, the need for high performance capacitors is bound to become indispensible. The current state-of-art employs ferroelectric ceramics and linear dielectrics for solid state capacitance. However, lead-free ferroelectric ceramics propose to offer significant improvement in the field of electrical energy storage owing to their high discharge efficiency and energy storage density. In this regards, the authors have investigated the effects of compressive stress as a means of improving the energy storage density of lead-free ferroelectric ceramics. The energy storage density of 0.91(Bi{sub 0.5}Na{sub 0.5})TiO{sub 3}-0.07BaTiO{sub 3}-0.02(K{sub 0.5}Na{sub 0.5})NbO{sub 3} ferroelectric bulk ceramic was analyzed as a function of varying levels of compressive stress and operational temperature .It was observed that a peak energy density of 387 mJ.cm{sup -3} was obtained at 100 MPa applied stress (25{sup o}C). While a maximum energy density of 568 mJ.cm{sup -3} was obtained for the same stress at 80{sup o}C. These values are indicative of a significant, 25% and 84%, improvement in the value of stored energy compared to an unloaded material. Additionally, material's discharge efficiency has also been discussed as a function of operational parameters. The observed phenomenon has been explained on the basis of field induced structural transition and competitive domain switching theory.

Chauhan, Aditya; Patel, Satyanarayan; Vaish, Rahul, E-mail: rahul@iitmandi.ac.in [School of Engineering, Indian Institute of Technology Mandi, 175 001 (India)

2014-08-15T23:59:59.000Z

265

Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory  

SciTech Connect (OSTI)

We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The density of uniformly distributed sources of equal intrinsic intensity was found to be larger than ? (0.06?5) × 10{sup ?4} Mpc{sup ?3} at 95% CL, depending on the magnitude of the magnetic deflections. Similar bounds, in the range (0.2?7) × 10{sup ?4} Mpc{sup ?3}, were obtained for sources following the local matter distribution.

Collaboration: Pierre Auger Collaboration

2013-05-01T23:59:59.000Z

266

BiFeO3 Domain Wall Energies and Structures: A Combined Experimental and Density Functional Theory+U Study  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We determined the atomic structures and energies of 109°, 180°, and 71° domain walls in BiFeO3, combining density functional theory+U calculations and aberration-corrected transmission electron microscopy images. We find a substantial Bi sublattice shift and a rather uniform Fe sublattice across the walls. The calculated wall energies (?) follow the sequence ?109 180 71 for the 109°, 180°, and 71° walls. We attribute the high 71° wall energy to an opposite tilting rotation of the oxygen octahedra and the low 109° wall energy to the opposite twisting rotation of the oxygen octahedra across the domain walls.

Wang, Yi; Nelson, Chris; Melville, Alexander; Winchester, Benjamin; Shang, Shunli; Liu, Zi-Kui; Schlom, Darrell G.; Pan, Xiaoqing; Chen, Long-Qing

2013-06-01T23:59:59.000Z

267

Recent developments in classical density functional theory: Internal energy functional and diagrammatic structure of fundamental measure theory  

E-Print Network [OSTI]

An overview of several recent developments in density functional theory for classical inhomogeneous liquids is given. We show how Levy's constrained search method can be used to derive the variational principle that underlies density functional theory. An advantage of the method is that the Helmholtz free energy as a functional of a trial one-body density is given as an explicit expression, without reference to an external potential as is the case in the standard Mermin-Evans proof by reductio ad absurdum. We show how to generalize the approach in order to express the internal energy as a functional of the one-body density distribution and of the local entropy distribution. Here the local chemical potential and the bulk temperature play the role of Lagrange multipliers in the Euler-Lagrange equations for minimiziation of the functional. As an explicit approximation for the free-energy functional for hard sphere mixtures, the diagrammatic structure of Rosenfeld's fundamental measure density unctional is laid out. Recent extensions, based on the Kierlik-Rosinberg scalar weight functions, to binary and ternary non-additive hard sphere mixtures are described.

M. Schmidt; M. Burgis; W. S. B. Dwandaru; G. Leithall; P. Hopkins

2012-12-27T23:59:59.000Z

268

The Impact of Residential Density on Vehicle Usage and Energy Consumption  

E-Print Network [OSTI]

Vehicle Usage and Energy Consumption Table 2 Housing Unitsresidential vehicular energy consumption is graphed as aon Vehicle Usage and Energy Consumption with vehicles, but

Golob, Thomas F.; Brownstone, David

2005-01-01T23:59:59.000Z

269

Improved Battery Pack Thermal Management to Reduce Cost and Increase Energy Density: Cooperative Research and Development Final Report, CRADA Number CRD-12-499  

SciTech Connect (OSTI)

Under this CRADA NREL will support Creare's project for the Department of Energy entitled 'Improved Battery Pack Thermal Management to Reduce Cost and Increase Energy Density' which involves the development of an air-flow based cooling product that increases energy density, safety, and reliability of hybrid electric vehicle battery packs.

Smith, K.

2013-10-01T23:59:59.000Z

270

Functional approach for pairing in finite systems: How to define restoration of broken symmetries in Energy Density Functional theory ?  

E-Print Network [OSTI]

The Multi-Reference Energy Density Functional (MR-EDF) approach (also called configuration mixing or Generator Coordinate Method), that is commonly used to treat pairing in finite nuclei and project onto particle number, is re-analyzed. It is shown that, under certain conditions, the MR-EDF energy can be interpreted as a functional of the one-body density matrix of the projected state with good particle number. Based on this observation, we propose a new approach, called Symmetry-Conserving EDF (SC-EDF), where the breaking and restoration of symmetry are accounted for simultaneously. We show, that such an approach is free from pathologies recently observed in MR-EDF and can be used with a large flexibility on the density dependence of the functional.

Guillaume Hupin; Denis Lacroix; Michael Bender

2011-05-30T23:59:59.000Z

271

Applications of Robust, Radiation Hard AlGaN Optoelectronic Devices in Space Exploration and High Energy Density Physics  

SciTech Connect (OSTI)

This slide show presents: space exploration applications; high energy density physics applications; UV LED and photodiode radiation hardness; UV LED and photodiode space qualification; UV LED AC charge management; and UV LED satellite payload instruments. A UV LED satellite will be launched 2nd half 2012.

Sun, K.

2011-05-04T23:59:59.000Z

272

The need for high density energy storage for wind turbine and solar power has proven to be a  

E-Print Network [OSTI]

1 The need for high density energy storage for wind turbine and solar power has proven cost of these components but also considerably improve their lifetime and reliability as it removes. New breakthrough for single-layer ceramic capacitors with high performance #12;2 Benefits ANU has

Botea, Adi

273

High Energy Density and Breakdown Strength from ? and ? Phases in Poly(vinylidene fluoride-co-bromotrifluoroethylene) Copolymers  

Science Journals Connector (OSTI)

Poly(vinylidene fluoride) PVDF-based copolymers represent the state of the art dielectric polymers for high energy density capacitors. Past work on these copolymers has been done with limited emphasis on the effects of copolymer composition and with a ...

Matthew R. Gadinski; Kuo Han; Qi Li; Guangzu Zhang; Wuttiichai Reainthippayasakul; Qing Wang

2014-10-16T23:59:59.000Z

274

Density Log at Fish Lake Valley Area (DOE GTP) | Open Energy...  

Open Energy Info (EERE)

Fish Lake Valley Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Density Log at Fish Lake Valley Area (DOE GTP) Exploration...

275

Density Log at Fort Bliss Area (DOE GTP) | Open Energy Information  

Open Energy Info (EERE)

Fort Bliss Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Density Log at Fort Bliss Area (DOE GTP) Exploration Activity Details...

276

Maximizing net income for pork producers by determining the interaction between dietary energy concentration and stocking density on finishing pig performance, welfare, and carcass composition.  

E-Print Network [OSTI]

??Marketplace volatility in the pork industry demands that producers re-evaluate production practices in order to remain profitable. Stocking density and dietary energy concentration independently affect… (more)

Rozeboom, Garrett

2015-01-01T23:59:59.000Z

277

Graphene-wrapped sulfur nanospheres with ultra-high sulfur loading for high energy density lithium–sulfur batteries  

Science Journals Connector (OSTI)

Abstract Lithium–sulfur (Li–S) battery with high theoretical energy density is one of the most promising energy storage systems for electric vehicles and intermittent renewable energy. However, due to the poor conductivity of the active material, considerable weight of the electrode is occupied by the conductive additives. Here we report a graphene-wrapped sulfur nanospheres composite (S-nanosphere@G) with sulfur content up to 91 wt% as the high energy density cathode material for Li–S battery. The sulfur nanospheres with diameter of 400–500 nm are synthesized through a solution-based approach with the existence of polyvinylpyrrolidone (PVP). Then the sulfur nanospheres are uniformly wrapped by conductive graphene sheets through the electrostatic interaction between graphene oxide and PVP, followed by reducing of graphene oxide with hydrazine. The design of graphene wrapped sulfur nanoarchitecture provides flexible conductive graphene coating with void space to accommodate the volume expansion of sulfur and to minimize polysulfide dissolution. As a result, the S-nanosphere@G nanocomposite with 91 wt% sulfur shows a reversible initial capacity of 970 mA h g?1 and an average columbic efficiency > 96% over 100 cycles at a rate of 0.2 C. Taking the total mass of electrode into account, the S-nanosphere@G composite is a promising cathode material for high energy density Li–S batteries.

Ya Liu; Jinxin Guo; Jun Zhang; Qingmei Su; Gaohui Du

2015-01-01T23:59:59.000Z

278

Higher Education  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Education » Education » Higher Education Higher Education Explore the multiple dimensions of a career at LANL: work with brilliant minds in an inclusive environment rich in intellectual vitality and opportunities for growth. Contact Education Janelle Vigil-Maestas Community Programs Office (505) 665-4329 Email "The partnership between LANL and regional colleges creates opportunities for students like me to attain challenging and rewarding careers." - Sherry Salas Bachicha Higher Education Resources for Undergraduates, Graduates & Postdocs Opportunities LANL Foundation Scholarships LANL Post Doc Program Programs Certificate in Environmental Monitoring (pdf) Community College Institute (CCI) (pdf) Computer Science and Information Technology Pipeline Program (ADIT/HPC Division) (pdf)

279

Stimulated scattering in laser driven fusion and high energy density physics experiments  

SciTech Connect (OSTI)

In laser driven fusion and high energy density physics experiments, one often encounters a k?{sub D} range of 0.15?

Yin, L., E-mail: lyin@lanl.gov; Albright, B. J.; Rose, H. A.; Montgomery, D. S.; Kline, J. L.; Finnegan, S. M.; Bergen, B.; Bowers, K. J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Kirkwood, R. K.; Milovich, J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2014-09-15T23:59:59.000Z

280

Research on Factors Relating to Density and Climate Change | Open Energy  

Open Energy Info (EERE)

Research on Factors Relating to Density and Climate Change Research on Factors Relating to Density and Climate Change Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Research on Factors Relating to Density and Climate Change Agency/Company /Organization: National Association of Home Builders Focus Area: Multi-sector Impact Evaluation Topics: Policy Impacts Resource Type: Reports, Journal Articles, & Tools Website: www.nahb.org/fileUpload_details.aspx?contentID=139993 This document talks about the increase residential density, primarily on the grounds that it will reduce vehicle miles traveled,a measure that is closely related to the GHG emissions from driving. References Retrieved from "http://en.openei.org/w/index.php?title=Research_on_Factors_Relating_to_Density_and_Climate_Change&oldid=515031"

Note: This page contains sample records for the topic "higher energy 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

The Impact of Residential Density on Vehicle Usage and Energy Consumption  

E-Print Network [OSTI]

on Vehicle Usage and Energy Consumption References Bento,Vehicle Usage and Energy Consumption UCI-ITS-WP-05-1 Thomason Vehicle Usage and Energy Consumption Thomas F. Golob

Golob, Thomas F; Brownstone, David

2005-01-01T23:59:59.000Z

282

Energy Spectra and Normalized Power Spectral Densities of X-Ray Nova GS 2000+25  

Science Journals Connector (OSTI)

......research-article Papers 2020 8320 Energy Spectra and Normalized...224-0817 The X-ray energy spectra and Normalized...Conf. Proc. 115, High Energy Transients in Astrophysics, ed. Woosley S. E. (New York: AIP), 31. White N......

Kentaro Terada; Shunji Kitamoto; Hitoshi Negoro; Sayuri Iga

2002-08-25T23:59:59.000Z

283

Vehicle Technologies Office Merit Review 2014: High Energy Density Li-ion Cells for EV’s Based on Novel, High Voltage Cathode Material Systems  

Broader source: Energy.gov [DOE]

Presentation given by Farasis Energy, Inc. at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high energy density Li...

284

Radiation from Ag high energy density Z-pinch plasmas and applications to lasing  

SciTech Connect (OSTI)

Silver (Ag) wire arrays were recently introduced as efficient x-ray radiators and have been shown to create L-shell plasmas that have the highest electron temperature (>1.8?keV) observed on the Zebra generator so far and upwards of 30?kJ of energy output. In this paper, results of single planar wire arrays and double planar wire arrays of Ag and mixed Ag and Al that were tested on the UNR Zebra generator are presented and compared. To further understand how L-shell Ag plasma evolves in time, a time-gated x-ray spectrometer was designed and fielded, which has a spectral range of approximately 3.5–5.0?Å. With this, L-shell Ag as well as cold L{sub ?} and L{sub ?} Ag lines was captured and analyzed along with photoconducting diode (PCD) signals (>0.8?keV). Along with PCD signals, other signals, such as filtered XRD (>0.2?keV) and Si-diodes (SiD) (>9?keV), are analyzed covering a broad range of energies from a few eV to greater than 53?keV. The observation and analysis of cold L{sub ?} and L{sub ?} lines show possible correlations with electron beams and SiD signals. Recently, an interesting issue regarding these Ag plasmas is whether lasing occurs in the Ne-like soft x-ray range, and if so, at what gains? To help answer this question, a non-local thermodynamic equilibrium (LTE) kinetic model was utilized to calculate theoretical lasing gains. It is shown that the Ag L-shell plasma conditions produced on the Zebra generator at 1.7 maximum current may be adequate to produce gains as high as 6?cm{sup ?1} for various 3p???3s transitions. Other potential lasing transitions, including higher Rydberg states, are also included in detail. The overall importance of Ag wire arrays and plasmas is discussed.

Weller, M. E., E-mail: mweller@unr.edu; Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Shrestha, I.; Stafford, A.; Keim, S. F.; Shlyaptseva, V. V.; Osborne, G. C.; Petkov, E. E. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States)] [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Apruzese, J. P.; Giuliani, J. L. [Naval Research Laboratory, Washington, District of Columbia 20375 (United States)] [Naval Research Laboratory, Washington, District of Columbia 20375 (United States); Chuvatin, A. S. [Ecole Polytechnique, 91128 Palaiseau (France)] [Ecole Polytechnique, 91128 Palaiseau (France)

2014-03-15T23:59:59.000Z

285

Density Log at Alum Area (Moos & Ronne, 2010) | Open Energy Information  

Open Energy Info (EERE)

Moos & Ronne, 2010) Moos & Ronne, 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Density Log at Alum Geothermal Area (Moos & Ronne, 2010) Exploration Activity Details Location Alum Geothermal Area Exploration Technique Density Log Activity Date Usefulness useful DOE-funding Unknown Notes Density, photo-electric factor (PEF), neutron, and gamma ray (GR) logs provided sufficient information to clearly delineate basement lithologic variations, suggesting that pulsed neutron logs may not in many cases be needed, and density and electrical resistivity data were important to calibrate structural models based on surface surveys. References Daniel Moos, Joel Ronne (2010) Selecting The Optimal Logging Suite For Geothermal Reservoir Evaluation- Results From The Alum 25-29 Well,

286

CO2/oxalate Cathodes as Safe and Efficient Alternatives in High Energy Density Metal-Air Type Rechargeable Batteries  

E-Print Network [OSTI]

We present theoretical analysis on why and how rechargeable metal-air type batteries can be made significantly safer and more practical by utilizing CO2/oxalate conversions instead of O2/peroxide or O2/hydroxide ones, in the positive electrode. Metal-air batteries, such as the Li-air one, may have very large energy densities, comparable to that of gasoline, theoretically allowing for long range all-electric vehicles. There are, however, still significant challenges, especially related to the safety of their underlying chemistries, the robustness of their recharging and the need of supplying high purity O2 from air to the battery. We point out that the CO2/oxalate reversible electrochemical conversion is a viable alternative of the O2-based ones, allowing for similarly high energy density and almost identical voltage, while being much safer through the elimination of aggressive oxidant peroxides and the use of thermally stable, non-oxidative and environmentally benign oxalates instead.

Nemeth, Karoly

2013-01-01T23:59:59.000Z

287

Energy Density Functionals From the Strong-Coupling Limit Applied to the Anions of the He Isoelectronic Series  

E-Print Network [OSTI]

Anions and radicals are important for many applications including environmental chemistry, semiconductors, and charge transfer, but are poorly described by the available approximate energy density functionals. Here we test an approximate exchange-correlation functional based on the exact strong-coupling limit of the Hohenberg-Kohn functional on the prototypical case of the He isoelectronic series with varying nuclear charge $Z$, which includes weakly bound negative ions and a quantum phase transition at a critical value of $Z$, representing a big challenge for density functional theory. We use accurate calculations to validate our results, comparing energies and Kohn-Sham potentials. We show that our functional is able to bind H$^-$ and to capture in general the physics of loosely bound anions, with a tendency to overbind that can be proven mathematically. We also include corrections based on the uniform electron gas which largely improve the results.

Mirtschink, André; Morgan, John D; Gori-Giorgi, Paola

2014-01-01T23:59:59.000Z

288

Elevated Temperature Materials for Power Generation and Propulsion The energy industry is designing higher-efficiency land-based turbines for natural gas-fired  

E-Print Network [OSTI]

higher-efficiency land-based turbines for natural gas-fired power generation systems. The high inletElevated Temperature Materials for Power Generation and Propulsion The energy industry is designing of thermomechanical fatigue life of the next generation's Ni-base superalloys are being developed to enhance life

Li, Mo

289

Permeation of low-Z atoms through carbon sheets: Density functional theory study on energy barriers and deformation effects  

SciTech Connect (OSTI)

Energetic and geometric aspects of the permeation of the atoms hydrogen to neon neutral atoms through graphene sheets are investigated by investigating the associated energy barriers and sheet deformations. Density functional theory calculations on cluster models, where graphene is modeled by planar polycyclic aromatic hydrocarbons (PAHs), provide the energies and geometries. Particularities of our systems, such as convergence of both energy barriers and deformation curves with increasing size of the PAHs, are discussed. Three different interaction regimes, adiabatic, planar and vertical, are investigated by enforcing different geometrical constraints. The adiabatic energy barriers range from 5 eV for hydrogen to 20 eV for neon. We find that the permeation of oxygen and carbon into graphene is facilitated by temporary chemical bonding while for other, in principle reactive atoms, it is not. We discuss implications of our results for modeling chemical sputtering of graphite.

Huber, Stefan E., E-mail: s.huber@uibk.ac.at, E-mail: Michael.probst@uibk.ac.at; Mauracher, Andreas; Probst, Michael, E-mail: s.huber@uibk.ac.at, E-mail: Michael.probst@uibk.ac.at [Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck (Austria)] [Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstraße 25, 6020 Innsbruck (Austria)

2013-12-15T23:59:59.000Z

290

Photodynamic inactivation of Candida albicans mediated by a low density of light energy  

Science Journals Connector (OSTI)

Shorter times and lower energies of application of light sources are desirable to use photodynamic antimicrobial ... of candidiasis, especially among babies and children. Light energies ranging from 39.5 to 100 J...

Gabriel Salles Barbério; Soraia Veloso da Costa…

2014-05-01T23:59:59.000Z

291

Density Perturbations in the Upper Atmosphere Caused by the Dissipation of Solar Wind Energy  

Science Journals Connector (OSTI)

The upper atmosphere constitutes the outer region of the terrestrial gas envelope above about 100 km altitude. The energy budget of this outer gas layer is partly controlled by the dissipation of solar wind energy

Gerd W. Prölss

2011-03-01T23:59:59.000Z

292

Photodynamic Effect of Hematoporphyrin Derivative as a Function of Optical Spectrum and Incident Energy Density  

Science Journals Connector (OSTI)

...visible light, i.e., low energy photons, the photodynamic effect...quanta rather than on incident energy. The work reported here represents...content and total delivered light energy on cell survival. MATERIALS...cially available 1000 watt Xenon solar simulator (Oriel Corporation...

J. H. Kinsey; D. A. Cortese; H. L. Moses; R. J. Ryan; and E. L. Branum

1981-12-01T23:59:59.000Z

293

Effect of Dietary Energy Restriction on Vascular Density during Mammary Carcinogenesis  

Science Journals Connector (OSTI)

...measured as vessels/unit area, of premalignant...adenocarcinomas from dietary energy restriction rats...Specifically, dietary energy restriction reduced...vessel area/unit of assessed area...differences in the measurement process, this...exerted by dietary energy restriction used...area or counts/unit of assessed area...

Henry J. Thompson; John N. McGinley; Nicole S. Spoelstra; Weiqin Jiang; Zongjian Zhu; and Pamela Wolfe

2004-08-15T23:59:59.000Z

294

The density-of-states concept versus the experimentally determined distribution of activation energies  

SciTech Connect (OSTI)

Random fluctuations of localized state energies will result in thermal release of carriers trapped in those states at shorter times than would be observed from a stationary distribution of the same energies. An experimentally observed distribution of activation energies will hence differ from the distribution of average energies of the states involved. It will also be temperature-dependent. In a-Si:H, low-frequency fluctuations with a spectrum comparable to the one of 1/f noise, can account for the measured temperature dependence of the distribution. They also explain the apparent shift in localized-state energy under steady-state illumination.

Adriaenssens, G.J.; Arkhipov, V.I. [Katholieke Univ. Leuven, Heverlee-Leuven (Belgium). Lab. voor Halfgeleiderfysica

1996-12-31T23:59:59.000Z

295

Efficient k?p method for the calculation of total energy and electronic density of states  

Science Journals Connector (OSTI)

An efficient method for calculating the electronic structure in large systems with a fully converged Brillouin zone sampling is presented. The method is based on a k?p-like approximation developed in the framework of the density-functional perturbation theory. The reliability and efficiency of the method are demonstrated in test calculations on Ar and Si supercells.

Marcella Iannuzzi and Michele Parrinello

2001-11-15T23:59:59.000Z

296

Full charge-density scheme with a kinetic-energy correction: Application to ground-state properties of the 4d metals  

Science Journals Connector (OSTI)

We present a full charge-density technique to evaluate total energies from the output of self-consistent linear muffin-tin orbitals (LMTO) calculations in the atomic-sphere approximation (ASA). The Coulomb energy is calculated exactly from the complete, nonspherically symmetric charge density defined within nonoverlapping, space-filling Wigner-Seitz cells; the exchange-correlation energy is evaluated by means of the local-density approximation or the generalized gradient approximation applied to the complete charge-density; and the ASA kinetic energy is corrected for the nonspherically symmetric charge density by a gradient expansion. The technique retains most of the simplicity and the computational efficiency of the LMTO-ASA method, and calculations of atomic volumes and elastic constants of the 4d elements show that it has the accuracy of full-potential methods.

L. Vitos; J. Kollár; H. L. Skriver

1997-05-15T23:59:59.000Z

297

Strain energy density: Distance criterion for the initiation of hydrogen-induced cracking of Alloy X-750  

SciTech Connect (OSTI)

A criterion for initiation of subcritical crack growth at blunt notches and sharp defects was developed and applied to hydrogen- induced cracking of the Ni-base superalloy X-750. Onset of crack growth is shown to occur when a critical strain energy density is attained at a distance from the notch and crack tips characteristic of the microstructure along the prospective crack path. Rising load crack growth initiation data were obtained using homogeneous hydrogen precharged notched and fatigue precracked bend specimens. Notch root radius, grain size and hydrogen concentration were varied. Crack growth initiation loads were dependent on both notch root radius and bulk precharged hydrogen concentration. These data were shown to be correlated using a critical strain energy at-a-distance (SEDAD) criterion. Furthermore, an elastic-plastic analysis of the strain energy distributions showed that the critical strain energy density value is attained at one grain diameter from the notch and fatigue precrack tips. Mechanical and microstructural aspects of crack growth process and relevance to hydrogen-induced cracking are discussed.

Hall, M.M. Jr.; Symons, D.M.; Kearns, J.J.

1991-12-31T23:59:59.000Z

298

High thermal energy storage density molten salts for parabolic trough solar power generation.  

E-Print Network [OSTI]

??New alkali nitrate-nitrite systems were developed by using thermodynamic modeling and the eutectic points were predicted based on the change of Gibbs energy of fusion.… (more)

Wang, Tao

2011-01-01T23:59:59.000Z

299

The National Ignition Facility Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies  

E-Print Network [OSTI]

The National Ignition Facility (NIF) currently under construction at the University of California Lawrence Livermore National Laboratory (LLNL) is a 192-beam, 1.8-megajoule, 500-terawatt, 351-nm laser for inertial confinement fusion (ICF) and high-energy-density experimental studies. NIF is being built by the Department of Energy and the National Nuclear Security Agency (NNSA) to provide an experimental test bed for the U.S. Stockpile Stewardship Program to ensure the country's nuclear deterrent without underground nuclear testing. The experimental program will encompass a wide range of physical phenomena from fusion energy production to materials science. Of the roughly 700 shots available per year, about 10% will be dedicated to basic science research. Laser hardware is modularized into line replaceable units (LRUs) such as deformable mirrors, amplifiers, and multi-function sensor packages that are operated by a distributed computer control system of nearly 60,000 control points. The supervisory control roo...

Moses, E I

2001-01-01T23:59:59.000Z

300

Singlet-Triplet Energy Gaps for Diradicals from Fractional-Spin Density-Functional Theory  

SciTech Connect (OSTI)

Open-shell singlet diradicals are difficult to model accurately within conventional Kohn?Sham (KS) density-functional theory (DFT). These methods are hampered by spin contamination because the KS determinant wave function is neither a pure spin state nor an eigenfunction of the S2 operator. Here we present a theoretical foray for using single-reference closed-shell ground states to describe diradicals by fractional-spin DFT (FS-DFT). This approach allows direct, self-consistent calculation of electronic properties using the electron density corresponding to the proper spin eigenfunction. The resulting FS-DFT approach is benchmarked against diradical singlet?triplet gaps for atoms and small molecules. We have also applied FS-DFT to the singlet?triplet gaps of hydrocarbon polyacenes.

Ess, Daniel H.; Johnson, E R; Hu, Xiangqian; Yang, W T

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Experimental investigation of opacity models for stellar interior, inertial fusion, and high energy density plasmasa...  

E-Print Network [OSTI]

, Albuquerque, New Mexico, 87185-1196, USA 2 University of Nevada, Reno, Nevada 89557, USA 3 Lawrence Livermore for calculating energy transport in plasmas. In particular, understanding stellar interiors, inertial fusion more energy and the backlight must be bright enough to overwhelm the plasma self-emission

302

Kaon condensate with trapped neutrinos and high-density symmetry energy behavior  

E-Print Network [OSTI]

Effects of the neutrino trapping and symmetry energy behavior are investigated in the framework of the chiral Kaplan-Nelson model with kaon condensation. Decrease in the condensation threshold during deleptonization if found to be generic regardless uncertainties in the nucleon-kaon interactions and symmetry energy. Quantitatively however, differences are shown to be important

A. Odrzywolek; M. Kutschera

2007-03-27T23:59:59.000Z

303

Understanding the implications of the data from recent high-energy-density Kelvin-Helmholtz shear layer experiments  

SciTech Connect (OSTI)

The first successful high energy density Kelvin-Helmholtz (KH) shear layer experiments (O.A. Hurricane, et al., Phys. Plasmas, 16, 056305, 2009; E.C. Harding, et al., Phys. Rev. Lett., 103, 045005, 2009) demonstrated the ability to design and field a target that produces an array of large diagnosable KH vortices in a controlled fashion. Data from these experiments vividly showed the complete evolution of large distinct eddies, from formation to apparent turbulent break-up. Unexpectedly, low-density bubbles/cavities comparable to the vortex size ({approx} 300 - 400 {micro}m) appeared to grow up in the free-stream flow above the unstable material interface. In this paper, the basic principles of the experiment will be discussed, the data reviewed, and the progress on understanding the origin of the above bubble structures through theory and simulation will be reported on.

Hurricane, O A; Hansen, J F; Harding, E C; Drake, R P; Robey, H F; Remington, B A; Kuranz, C C; Grosskopf, M J; Gillespie, R S; Park, H

2009-10-26T23:59:59.000Z

304

Potential energy savings and reduction of CO2 emissions through higher efficiency standards for polyphase electric motors in Japan  

Science Journals Connector (OSTI)

Japan has shut down more than 70% of its nuclear power plants since the March 2011 Tohoku earthquake and the ensuing accident at the Fukushima Daiichi nuclear power plant. The country has been challenged with power shortages in the short-term and faces complex energy security decisions in the long-term. Japan has a long history of implementing energy conservation policies, such as the Top Runner Program, which covers 23 products including appliances and industrial equipment. However, Japan's efficiency policy for polyphase electric motors is considered below international standards. Polyphase electric motors accounted for about 55% of the nation's total power consumption in 2008. The aim of this study is to estimate potential energy savings and reduction in CO2 emissions (2014–2043) by examining scenarios involving adopting two different polyphase motor efficiency standards and comparing them to a base case and concludes by suggesting pathways for further policy development using the results obtained. The study finds that if level IE2 of the international efficiency standard IEC 60034-30 were implemented, it would save 8.3 TWh (or 0.03 quads) per year, which is equivalent to about 0.8% of Japan's total electric power consumption in 2010. If level IE3 of the IEC 60034-30 were implemented instead, it would save about 13.3 TWh (or 0.05 quads) per year. The corresponding cumulative energy savings and reduction in CO2 emissions for the IE2 scenario would be 249 TWh (or 0.85 quads) and 93 Mt. The corresponding cumulative energy savings and reduction in CO2 emissions for the IE3 scenario would be 398 TWh (or 1.36 quads) and 149 Mt.

Chun Chun Ni

2013-01-01T23:59:59.000Z

305

Measurements of electrical resistivity of heavy ion beam produced high energy density matter: Latest results for lead and tungsten  

Science Journals Connector (OSTI)

The high-intensity heavy ion beams provided by the accelerator facilities of the Gesellschaft für Schwerionenforschung (GSI) Darmstadt are an excellent tool to produce large volumes of high energy density (HED) matter. Thermophysical and transport properties of HED matter states are of interest for fundamental as well as for applied research. During the last few years development of new diagnostic techniques allowed for a series of measurements of the electrical resistivity of heavy ion beam generated HED matter. In this report we present the most recent results on electrical resistivity of HED matter at GSI. The experiments on which we report have been performed with targets consisting of tungsten wires and lead foils, respectively. Uranium and argon beam pulses with durations of a few hundred ns, intensities of about 2 × 10 9 and 1 × 10 11 ions / bunch , respectively, and an initial ion energy of 300–350 A MeV have been used as a driver. An energy density deposition of about 1 kJ/g has been achieved by focusing the ion beam down to 1 mm FWHM or less.

Serban Udrea; Vladimir Ternovoi; Nikolay Shilkin; Alexander Fertman; Vladimir E. Fortov; Dieter H.H. Hoffmann; Alexander Hug; Michail I. Kulish; Victor Mintsev; Pavel Ni; Dmitry Nikolaev; Naeem A. Tahir; Vladimir Turtikov; Dmitry Varentsov; Denis Yuriev

2007-01-01T23:59:59.000Z

306

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Internal tidal energy fluxes in the South China Sea from density  

E-Print Network [OSTI]

tide. Semidiurnal energy density is largest along a ray path which co- incides with generation sites of the largest internal tides in the ocean, with depth-integrated energy fluxes >60 kW m-1 , are gener- atedJOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Internal tidal energy fluxes

Johnston, Shaun

307

NEUTRON FLUX DENSITY AND SECONDARY-PARTICLE ENERGY SPECTRA AT THE 184-INCH SYNCHROCYCLOTRON MEDICAL FACILITY  

E-Print Network [OSTI]

Mischke, R. E. 1973a. Neutron-nucleus total and inelasticproduction of high-energy neutrons by stripping. Phys. Rev.1975. Dose rate due to neutrons around the alpha- Health

Smith, A.R.

2010-01-01T23:59:59.000Z

308

Toward high-energy-density, high-efficiency, and moderate-temperature chip-scale thermophotovoltaics  

Science Journals Connector (OSTI)

...processor. PhD thesis (Massachusetts Institute of Technology...generation. PhD thesis (Massachusetts Institute of Technology...partially supported by the Massachusetts Institute of Technology Solid State Solar Thermal Energy Conversion...

Walker R. Chan; Peter Bermel; Robert C. N. Pilawa-Podgurski; Christopher H. Marton; Klavs F. Jensen; Jay J. Senkevich; John D. Joannopoulos; Marin Solja?i?; Ivan Celanovic

2013-01-01T23:59:59.000Z

309

Improvements on carbon nanotube structures in high-energy density ultracapacitor electrode design  

E-Print Network [OSTI]

Ultracapacitors are a class of electrochemical energy storage device that is gaining significant industrial traction due to their high charging rate and cycle life compared to rechargeable batteries; however, they store ...

Jenicek, David P. (David Pierre)

2014-01-01T23:59:59.000Z

310

Copper nanocrystal modified activated carbon for supercapacitors with enhanced volumetric energy and power density  

E-Print Network [OSTI]

Copper nanocrystal modified activated carbon for supercapacitors with enhanced volumetric energy of copper nanocrystals in AC has little effect on the surface area and porosity of activated carbon. copper nanocrystals improves the electrical conductivity of the carbon network.

Cao, Guozhong

311

National Primary Special Standard for the Units of Energy, Energy Density Distribution, Pulse Duration, and Wavelength of Laser Radiation  

Science Journals Connector (OSTI)

The working standards are, as a rule, located in metrological centers and are used directly for calibration and verification of working means of measurement that are in operation. Transfer of the units of energy,...

K. Sh. Abdrakhmanov; A. A. Liberman; S. A. Moskalyuk…

2014-03-01T23:59:59.000Z

312

The effect of the H{sub 2} density on the electron energy distribution in H{sup ?} ion sources  

SciTech Connect (OSTI)

The electron energy distribution in H{sup ?} ion sources is studied. By three-dimensional Monte Carlo simulations (3D-MCC) and cross sections of collisions, the crucial collisions in the JAEA 10A are chosen to develop theoretical models for the low electron temperature and the high electron temperature, respectively. The effects of the H{sub 2} density on the low electron temperature and the high electron temperature in H{sup ?} ion sources are predicted with analytic expressions and verified by 3D-MCC. The results show that both the low and high electron temperatures become lower while n{sub H2} increases.

Wang, Huihui; Meng, Lin; Liu, Dagang; Liu, Laqun; Yang, Chao [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)] [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)

2013-09-15T23:59:59.000Z

313

Implications of higher energy - summary of benefits, issues, commissioning cost, SEU, Cryo, QPS margins, Potential availability issues  

E-Print Network [OSTI]

The LHC is technically almost ready to run at 4 TeV per beam in 2012. Nevertheless, a review of the advantages and disadvantages of such an energy step should be carefully made before taking this decision. There fore, this paper will summarize the benefits from the physics point of view; the potential issues like a possible increase of Single Event Errors , Unidentified Flying Objects, or a significant decrease of the quench margin from beam losses that, all in all , could lead to availability issues, compromising the integrated luminosity. And last but not least, the commissioning cost will be addressed.

Alemany, R

2012-01-01T23:59:59.000Z

314

Constraining the density dependence of the nuclear symmetry energy from an X-ray bursting neutron star  

E-Print Network [OSTI]

Neutrons stars lighter than the Sun are basically composed of nuclear matter of density up to around twice normal nuclear density. In our recent analyses, we showed that possible simultaneous observations of masses and radii of such neutron stars could constrain $\\eta\\equiv(K_0L^2)^{1/3}$, a combination of the incompressibility of symmetric nuclear matter $K_0$ and the density derivative of the nuclear symmetry energy $L$ that characterizes the theoretical mass-radius relation. In this paper, we focus on the mass-radius constraint of the X-ray burster 4U 1724-307 given by Suleimanov et al. (2011). We therefrom obtain the constraint that $\\eta$ should be larger than around 130 MeV, which in turn leads to $L$ larger than around 110, 98, 89, and 78 MeV for $K_0=180$, 230, 280, and 360 MeV. Such a constraint on $L$ is more or less consistent with that obtained from the frequencies of quasi-periodic oscillations in giant flares observed in soft-gamma repeaters.

Sotani, Hajime; Oyamatsu, Kazuhiro

2015-01-01T23:59:59.000Z

315

Low-momentum interactions with Brown-Rho-Ericson scalings, and the density dependence of the nuclear symmetry energy  

SciTech Connect (OSTI)

We have calculated the nuclear symmetry energy E{sub sym}({rho}) up to densities of 4-5{rho}{sub 0} with the effects from the Brown-Rho (BR) and Ericson scalings with the in-medium mesons included. Using the V{sub lowk} low-momentum interaction with and without such scalings, the equations of state (EOSs) of symmetric and asymmetric nuclear matter have been calculated using a ring-diagram formalism where the particle-particle-hole-hole ring diagrams are included to all orders. The EOSs for symmetric nuclear matter and neutron matter obtained with linear BR scaling are both overly stiff compared with the empirical constraints of Danielewicz et al. [Science 298, 1592 (2002)]. In contrast, satisfactory results are obtained by either using the nonlinear Ericson scaling or by adding a Skyrme-type three-nucleon force (TNF) to the unscaled V{sub lowk} interaction. Our results for E{sub sym}({rho}) obtained with the nonlinear Ericson scaling are in good agreement with the empirical values of Tsang et al. [Phys. Rev. Lett. 102, 122701 (2009)] and Li et al. [Phys. Rev. C 72, 064611 (2005)], while those with the TNF are slightly below these values. For densities below the nuclear saturation density {rho}{sub 0}, the results of the above calculations are nearly equivalent to each other and all are in satisfactory agreement with the empirical values.

Dong Huan; Kuo, T. T. S.; Machleidt, R. [Department of Physics and Astronomy, Stony Brook University, New York 11794-3800 (United States); Department of Physics, University of Idaho, Moscow, Idaho 83844 (United States)

2011-05-15T23:59:59.000Z

316

Low-momentum interactions with Brown-Rho-Ericson scalings and the density dependence of the nuclear symmetry energy  

E-Print Network [OSTI]

We have calculated the nuclear symmetry energy $E_{sym}(\\rho)$ up to densities of $4 \\sim 5 \\rho_0$ with the effects from the Brown-Rho (BR) and Ericson scalings for the in-medium mesons included. Using the $V_{low-k}$ low-momentum interaction with and without such scalings, the equations of state (EOS) of symmetric and asymmetric nuclear matter have been calculated using a ring-diagarm formalism where the particle-particle-hole-hole ring diagrams are included to all orders. The EOS for symmetric nuclear matter and neutron matter obtained with linear BR scaling are both overly stiff compared with the empirical constraints of Danielewicz {\\it et al.} \\cite{daniel02}. In contrast, satisfactory results are obtained by either using the nonlinear Ericson scaling or by adding a Skyrme-type three-nucleon force (TNF) to the unscaled $V_{low-k}$ interaction. Our results for $E_{sym}(\\rho)$ obtained with the nonlinear Ericson scaling are in good agreement with the empirical values of Tsang {\\it et al.} \\cite{tsang09} and Li {\\it et al.} \\cite{li05}, while those with TNF are slightly below these values. For densities below the nuclear saturation density $\\rho_0$, the results of the above calculations are nearly equivalent to each other and all in satisfactory agreement with the empirical values.

Huan Dong; T. T. S. Kuo; R. Machleidt

2011-01-10T23:59:59.000Z

317

Constraining the density dependence of the nuclear symmetry energy from an X-ray bursting neutron star  

E-Print Network [OSTI]

Neutrons stars lighter than the Sun are basically composed of nuclear matter of density up to around twice normal nuclear density. In our recent analyses, we showed that possible simultaneous observations of masses and radii of such neutron stars could constrain $\\eta\\equiv(K_0L^2)^{1/3}$, a combination of the incompressibility of symmetric nuclear matter $K_0$ and the density derivative of the nuclear symmetry energy $L$ that characterizes the theoretical mass-radius relation. In this paper, we focus on the mass-radius constraint of the X-ray burster 4U 1724-307 given by Suleimanov et al. (2011). We therefrom obtain the constraint that $\\eta$ should be larger than around 130 MeV, which in turn leads to $L$ larger than around 110, 98, 89, and 78 MeV for $K_0=180$, 230, 280, and 360 MeV. Such a constraint on $L$ is more or less consistent with that obtained from the frequencies of quasi-periodic oscillations in giant flares observed in soft-gamma repeaters.

Hajime Sotani; Kei Iida; Kazuhiro Oyamatsu

2015-01-08T23:59:59.000Z

318

Thermodynamics and heavy-quark free energies at finite temperature and density with two flavors of improved Wilson quarks  

E-Print Network [OSTI]

Thermodynamics of two-flavor QCD at finite temperature and density is studied on a $16^3 \\times 4$ lattice, using a renormalization group improved gauge action and the clover improved Wilson quark action. In the simulations along lines of constant $m_{\\rm PS}/m_{\\rm V}$, we calculate the Taylor expansion coefficients of the heavy-quark free energy with respect to the quark chemical potential ($\\mu_q$) up to the second order. By comparing the expansion coefficients of the free energies between quark($Q$)and antiquark($\\bar{Q}$), and between $Q$ and $Q$, we find a characteristic difference at finite $\\mu_q$ due to the first order coefficient of the Taylor expansion. We also calculate the quark number and isospin susceptibilities, and find that the second order coefficient of the quark number susceptibility shows enhancement around the pseudo-critical temperature.

Y. Maezawa; S. Aoki; S. Ejiri; T. Hatsuda; N. Ishii; K. Kanaya; N. Ukita; T. Umeda

2007-10-04T23:59:59.000Z

319

Origin of higher temperatures in multidipolar plasma devices  

SciTech Connect (OSTI)

Hot-filament discharge devices with multidipolar surface magnetic fields have densities and temperatures higher than in these devices without multidipolar fields. Probe data show a much higher density of secondary electrons from the wall with multidipolar fields that is best explained by the wall secondaries being confined by the magnetic mirror effect. A relatively simple mathematical model for energy balance shows that the heating of the bulk plasma electrons by collisions with the greater number of secondaries from the wall accounts quantitatively for the increased temperature.

Knappmiller, Scott [Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado 80309-0392 (United States); Robertson, Scott [Center for Integrated Plasma Studies, University of Colorado, Boulder, Colorado 80309-0390 (United States)

2011-10-15T23:59:59.000Z

320

Density slope of the nuclear symmetry energy from the neutron skin thickness of heavy nuclei  

E-Print Network [OSTI]

Board of Higher Education Award No. 003565-0004-2007. [1] B. A. Li, C. M. Ko, and W. Bauer, Int. J. Mod. Phys. E 7, 147 (1998). [2] P. Danielewicz, R. Lacey, and W. G. Lynch, Science 298, 1592 (2002). [3] J. M. Lattimer and M. Prakash, Science 304.... Li, Phys. Rev. C 76, 055804 (2007). [10] D. H. Wen, B. A. Li, and L. W. Chen, Phys. Rev. Lett. 103, 211102 (2009). [11] M. B. Tsang, Y. Zhang, P. Danielewicz, M. Famiano, Z. Li, W. G. Lynch, and A. W. Steiner, Phys. Rev. Lett. 102, 122701 (2009...

Chen, Lie-Wen; Ko, Che Ming; Li, Bao-An; Xu, Jun.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy density" from the National Library of EnergyBeta (NLEBeta).
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321

Energy density functionals from the strong-coupling limit applied to the anions of the He isoelectronic series  

SciTech Connect (OSTI)

Anions and radicals are important for many applications including environmental chemistry, semiconductors, and charge transfer, but are poorly described by the available approximate energy density functionals. Here we test an approximate exchange-correlation functional based on the exact strong-coupling limit of the Hohenberg-Kohn functional on the prototypical case of the He isoelectronic series with varying nuclear charge Z < 2, which includes weakly bound negative ions and a quantum phase transition at a critical value of Z, representing a big challenge for density functional theory. We use accurate wavefunction calculations to validate our results, comparing energies and Kohn-Sham potentials, thus also providing useful reference data close to and at the quantum phase transition. We show that our functional is able to bind H{sup ?} and to capture in general the physics of loosely bound anions, with a tendency to strongly overbind that can be proven mathematically. We also include corrections based on the uniform electron gas which improve the results.

Mirtschink, André; Gori-Giorgi, Paola [Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling, FEW, Vrije Universiteit, De Boelelaan 1083, 1081HV Amsterdam (Netherlands)] [Department of Theoretical Chemistry and Amsterdam Center for Multiscale Modeling, FEW, Vrije Universiteit, De Boelelaan 1083, 1081HV Amsterdam (Netherlands); Umrigar, C. J. [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853 (United States)] [Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853 (United States); Morgan, John D. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States)] [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States)

2014-05-14T23:59:59.000Z

322

A New Method to Reconstruct the Energy and Determine the Composition of Cosmic Rays from the Measurement of Cherenkov Light and Particle Densities in Extended Air Showers  

E-Print Network [OSTI]

A Monte-Carlo study is presented using ground based measurements of the electromagnetic part of showers initiated in the atmosphere by high energetic cosmic rays to reconstruct energy and mass of primary particles with energies above 300 TeV. With two detector arrays measuring Cherenkov light and particle densities as realized in the HEGRA experiment shower properties are reconstructed and interpreted to determine energy and energy per nucleon of the primary particle.

A. Lindner

1996-11-21T23:59:59.000Z

323

Extended performance gas Cherenkov detector for gamma-ray detection in high-energy density experiments  

SciTech Connect (OSTI)

A new Gas Cherenkov Detector (GCD) with low-energy threshold and high sensitivity, currently known as Super GCD (or GCD-3 at OMEGA), is being developed for use at the OMEGA Laser Facility and the National Ignition Facility (NIF). Super GCD is designed to be pressurized to ?400 psi (absolute) and uses all metal seals to allow the use of fluorinated gases inside the target chamber. This will allow the gamma energy threshold to be run as low at 1.8 MeV with 400 psi (absolute) of C{sub 2}F{sub 6}, opening up a new portion of the gamma ray spectrum. Super GCD operating at 20 cm from TCC will be ?400 × more efficient at detecting DT fusion gammas at 16.7 MeV than the Gamma Reaction History diagnostic at NIF (GRH-6m) when operated at their minimum thresholds.

Herrmann, H. W., E-mail: herrmann@lanl.gov; Kim, Y. H.; Young, C. S.; Fatherley, V. E.; Lopez, F. E.; Oertel, J. A.; Batha, S. H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Malone, R. M. [National Security Technologies, LLC, Los Alamos, New Mexico 87544 (United States); Rubery, M. S.; Horsfield, C. J. [Atomic Weapons Establishment, Aldermaston, Berkshire RG7 4PR (United Kingdom); Stoeffl, W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Zylstra, A. B. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Shmayda, W. T. [Laboratory for Laser Energetics, Rochester, New York 14623 (United States)

2014-11-15T23:59:59.000Z

324

Universal Nuclear Energy Density Functional: Tools and Resources from the UNEDF SciDAC Collaboration  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

UNEDF supports the Low-Energy Nuclear Physics National HPC Initiative. There are approximately 3,000 known nuclei, most of them produced in the laboratory, with an additional 6,000 that could in principle still be created. An understanding of the properties of these elements is crucial for future energy and defense applications. The long-term vision of UNEF is to arrive at a comprehensive and unified description of nuclei and their reactions, grounded in the fundamental interactions between the constituent nucleons. It seeks to replace current phenomenological models of nuclear structure and reactions with a well-founded microscopic theory that delivers maximum predictive power with well-quantified uncertainties.

325

Complex-energy approach to sum rules within nuclear density functional theory  

E-Print Network [OSTI]

The linear response of the nucleus to an external field contains unique information about the effective interaction, correlations, and properties of its excited states. To characterize the response, it is useful to use its energy-weighted moments, or sum rules. By comparing computed sum rules with experimental values, the information content of the response can be utilized in the optimization process of the nuclear Hamiltonian or EDF. But the additional information comes at a price: compared to the ground state, computation of excited states is more demanding. To establish an efficient framework to compute sum rules of the response that is adaptable to the optimization of the nuclear EDF and large-scale surveys of collective strength, we have developed a new technique within the complex-energy FAM based on the QRPA. To compute sum rules, we carry out contour integration of the response function in the complex-energy plane. We benchmark our results against the conventional matrix formulation of the QRPA theory...

Hinohara, Nobuo; Nazarewicz, Witold; Olsen, Erik

2015-01-01T23:59:59.000Z

326

Probing Ligand Effects on the Redox Energies of [4Fe-4S] Clusters Using Broken-Symmetry Density Functional Theory  

SciTech Connect (OSTI)

A central issue in understanding redox properties of iron-sulfur proteins is determining the factors that tune the reduction potentials of the Fe-S clusters. Recently, Solomon and coworkers have shown that the Fe-S bond covalency of protein analogs measured by %L, the percent ligand character of the Fe 3d orbitals, from ligand K-edge X-ray absorption spectroscopy (XAS) correlates with the electrochemical redox potentials. Also, Wang and coworkers have measured electron detachment energies for iron-sulfur clusters without environmental perturbations by gas-phase photoelectron spectroscopy (PES). Here the correlations of the ligand character with redox energy and %L character are examined in [Fe?S?L?]2? clusters with different ligands by broken symmetry density functional theory (BS-DFT) calculations using the B3LYP functional together with PES and XAS experimental results. These gas-phase studies assess ligand effects independently of environmental perturbations and thus provide essential information for computational studies of iron-sulfur proteins. The B3LYP oxidation energies agree well with PES data, and the %L character obtained from natural bond orbital analysis correlates with XAS values, although it systematically underestimates them because of basis set effects. The results show that stronger electron-donating terminal ligands increase %Lt, the percent ligand character from terminal ligands, but decrease %Sb, the percent ligand character from the bridging sulfurs. Because the oxidized orbital has significant Fe-Lt antibonding character, the oxidation energy correlates well with %Lt. However, because the reduced orbital has varying contributions of both Fe-Lt and Fe-Sb antibonding character, the reduction energy does not correlate with either %Lt or %Sb. Overall, BSDFT calculations together with XAS and PES experiments can unravel the complex underlying factors in the redox energy and chemical bonding of the [4Fe-4S] clusters in iron-sulfur proteins.

Niu, Shuqiang; Ichiye, Toshiko

2009-05-14T23:59:59.000Z

327

2010 DOE EERE Vehicle Technologies Program Merit Review - Energy...  

Broader source: Energy.gov (indexed) [DOE]

the development of the high voltage spinels and investigates anode materials based on the conversion reactions for higher energy density batteries. QUESTION 2: WHAT IS YOUR...

328

Origin of protons accelerated by an intense laser and the dependence of their energy on the plasma density  

Science Journals Connector (OSTI)

We study the high-energy (1–4 MeV) proton production from a slab plasma irradiated by a ultrashort high-power laser. In our 2.5-dimensional particle-in-cell simulations, a p-polarized laser beam of 1.6×1019 W/cm2, 300 fs, ?L=1.053 ?m, illuminates a slab plasma normally; the slab plasma consists of a hydrogen plasma, and the target plasma thickness and the laser spot size are 2.5?L and 5?L, respectively. The simulation results show that an emitted proton energy depends on the slab plasma density, and three kinds of high-energy proton beams are generated at the target plasma surfaces: one kind of the proton beams is produced at the laser-illuminated target surface and accelerated to the same laser-incident side. The second is generated at the target surface opposite to the laser-illuminated target surface and is accelerated outward on the same side. The third is generated at the laser-illuminated target surface and accelerated to the opposite side while passing through the target plasma. The simulations also show a mechanism of proton accelerations. In an overdense plasma, laser energy goes to energies of hot electrons and magnetic fields in part; the electrons oscillate around the slab plasma so that a static electric field is generated and consequently protons are extracted. The magnetic field generated in the slab plasma exists longer and heats up the plasma electrons to sustain the static electric field even after the laser termination.

Takashi Nakamura and Shigeo Kawata

2003-02-06T23:59:59.000Z

329

The National Ignition Facility: Status and Plans for Laser Fusion and High-Energy-Density Experimental Studies  

E-Print Network [OSTI]

The National Ignition Facility (NIF) currently under construction at the University of California Lawrence Livermore National Laboratory (LLNL) is a 192-beam, 1.8-megajoule, 500-terawatt, 351-nm laser for inertial confinement fusion (ICF) and high-energy-density experimental studies. NIF is being built by the Department of Energy and the National Nuclear Security Agency (NNSA) to provide an experimental test bed for the U.S. Stockpile Stewardship Program to ensure the country's nuclear deterrent without underground nuclear testing. The experimental program will encompass a wide range of physical phenomena from fusion energy production to materials science. Of the roughly 700 shots available per year, about 10% will be dedicated to basic science research. Laser hardware is modularized into line replaceable units (LRUs) such as deformable mirrors, amplifiers, and multi-function sensor packages that are operated by a distributed computer control system of nearly 60,000 control points. The supervisory control room presents facility-wide status and orchestrates experiments using operating parameters predicted by physics models. A network of several hundred front-end processors (FEPs) implements device control. The object-oriented software system is implemented in the Ada and Java languages and emphasizes CORBA distribution of reusable software objects. NIF is currently scheduled to provide first light in 2004 and will be completed in 2008.

E. I. Moses

2001-11-09T23:59:59.000Z

330

High resolution 17 keV to 75 keV backlighters for High Energy Density experiments  

SciTech Connect (OSTI)

We have developed 17 keV to 75 keV 1-dimensional and 2-dimensional high-resolution (< 10 {micro}m) radiography using high-intensity short pulse lasers. High energy K-{alpha} sources are created by fluorescence from hot electrons interacting in the target material after irradiation by lasers with intensity I{sub L} > 10{sup 17} W/cm{sup 2}. We have achieved high resolution point projection 1-dimensional and 2-dimensional radiography using micro-foil and micro-wire targets attached to low-Z substrate materials. The micro-wire size was 10 {micro}m x 10 {micro}m x 300 {micro}m on a 300 {micro}m x 300 {micro}m x 5 {micro}m CH substrate. The radiography performance was demonstrated using the Titan laser at LLNL. We observed that the resolution is dominated by the micro-wire target size and there is very little degradation from the plasma plume, implying that the high energy x-ray photons are generated mostly within the micro-wire volume. We also observe that there are enough K{alpha} photons created with a 300 J, 1-{omega}, 40 ps pulse laser from these small volume targets, and that the signal-to-noise ratio is sufficiently high, for single shot radiography experiments. This unique technique will be used on future high energy density (HED) experiments at the new Omega-EP, ZR and NIF facilities.

Park, H; Maddox, B R; Giraldez, E; Hatchett, S P; Hudson, L; Izumi, N; Key, M H; Pape, S L; MacKinnon, A J; MacPhee, A G; Patel, P K; Phillips, T W; Remington, B A; Seely, J F; Tommasini, R; Town, R; Workman, J

2008-02-25T23:59:59.000Z

331

High-energy-density solid and liquid hydrocarbon fuels. Final report, July 1987-December 1988  

SciTech Connect (OSTI)

The development of new high-energy hydrocarbon fuels for use in air-breathing missiles has been the objective of a number of investigations which have received support during the past decade through programs sponsored by the Air Force Systems Command and/or the Naval Air Systems Command. The key characteristics which must be met by potential cruise missile fuels have been described by Burdette and coworkers. A primary requirement in this regard is that candidate fuels must possess high net volumetric heat of combustion (preferably greater than 160,000 BTU/gallon). In order to meet the primary requirement of high net volumetric heat of combustion, hydrocarbon systems have been sought which maximize the ratio of carbon-atom to hydrogen-atom content have been sought that maximize the ratio n/m.(JES)

Marchand, A.P.

1989-02-01T23:59:59.000Z

332

Stored energies in electric and magnetic current densities for small antennas  

E-Print Network [OSTI]

Electric and magnetic currents are essential to describe electromagnetic stored energy, as well as the associated quantities of antenna Q and the partial directivity to antenna Q-ratio, D/Q, for general structures. The upper bound of previous D/Q-results for antennas modeled by electric currents is accurate enough to be predictive, this motivates us here to extend the analysis to include magnetic currents. In the present paper we investigate antenna Q bounds and D/Q-bounds for the combination of electric- and magnetic-currents, in the limit of electrically small antennas. This investigation is both analytical and numerical, and we illustrate how the bounds depend on the shape of the antenna. We show that the antenna Q can be associated with the largest eigenvalue of certain combinations of the electric and magnetic polarizability tensors. The results are a fully compatible extension of the electric only currents, which come as a special case. The here proposed method for antenna Q provides the minimum Q-value...

Jonsson, B L G

2014-01-01T23:59:59.000Z

333

Potential of dual-energy subtraction for converting CT numbers to electron density based on a single linear relationship  

SciTech Connect (OSTI)

Purpose: The conversion of the computed tomography (CT) number to electron density is one of the main processes that determine the accuracy of patient dose calculations in radiotherapy treatment planning. However, the CT number and electron density of tissues cannot be generally interrelated via a simple one-to-one correspondence because the CT number depends on the effective atomic number as well as the electron density. The purpose of this study is to present a simple conversion from the energy-subtracted CT number ({Delta}HU) by means of dual-energy CT (DECT) to the relative electron density ({rho}{sub e}) via a single linear relationship. Methods: The {Delta}HU-{rho}{sub e} conversion method was demonstrated by performing analytical DECT image simulations that were intended to imitate a second-generation dual-source CT (DSCT) scanner with an additional tin filtration for the high-kV tube. The {Delta}HU-{rho}{sub e} calibration line was obtained from the image simulation with a 33 cm-diameter electron density calibration phantom equipped with 16 inserts including polytetrafluoroethylene, polyvinyl chloride, and aluminum; the elemental compositions of these three inserts were quite different to those of body tissues. The {Delta}HU-{rho}{sub e} conversion method was also applied to previously published experimental CT data, which were measured using two different CT scanners, to validate the clinical feasibility of the present approach. In addition, the effect of object size on {rho}{sub e}-calibrated images was investigated by image simulations using a 25 cm-diameter virtual phantom for two different filtrations: with and without the tin filter for the high-kV tube. Results: The simulated {Delta}HU-{rho}{sub e} plot exhibited a predictable linear relationship over a wide range of {rho}{sub e} from 0.00 (air) to 2.35 (aluminum). Resultant values of the coefficient of determination, slope, and intercept of the linear function fitted to the data were close to those of the ideal case. The maximum difference between the ideal and simulated {rho}{sub e} values was -0.7%. The satisfactory linearity of {Delta}HU-{rho}{sub e} was also confirmed from analyses of the experimental CT data. In the experimental cases, the maximum difference between the nominal and simulated {rho}{sub e} values was found to be 2.5% after two outliers were excluded. When compared with the case without the tin filter, the {Delta}HU-{rho}{sub e} conversion performed with the tin filter yielded a lower dose and more reliable {rho}{sub e} values that were less affected by the object-size variation. Conclusions: The {Delta}HU-{rho}{sub e} calibration line with a simple one-to-one correspondence would facilitate the construction of a well-calibrated {rho}{sub e} image from acquired dual-kV images, and currently, second generation DSCT may be a feasible modality for the clinical use of the {Delta}HU-{rho}{sub e} conversion method.

Saito, Masatoshi [Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Niigata University, Niigata 951-8518 (Japan)

2012-04-15T23:59:59.000Z

334

Higher Education | Department of Energy  

Energy Savers [EERE]

Chemist working in a laboratory. Students considering or planning for a career in a hydrogen- or fuel-cell-related field can use the resources below to read about available...

335

Time-dependent Maxwell field operators and field energy density for an atom near a conducting wall  

E-Print Network [OSTI]

We consider the time evolution of the electric and magnetic field operators for a two-level atom, interacting with the electromagnetic field, placed near an infinite perfectly conducting wall. We solve iteratively the Heisenberg equations for the field operators and obtain the electric and magnetic energy density operators around the atom (valid for any initial state). Then we explicitly evaluate them for an initial state with the atom in its bare ground state and the field in the vacuum state. We show that the results can be physically interpreted as the superposition of the fields propagating directly from the atom and the fields reflected on the wall. Relativistic causality in the field propagation is discussed. Finally we apply these results to the calculation of the dynamical Casimir-Polder interaction energy in the far zone between two atoms when a boundary condition such as a conducting wall is present. Magnetic contributions to the interatomic Casimir-Polder interaction in the presence of the wall are also considered. We show that, in the limit of large times, the known results of the stationary case are recovered.

R. Vasile; R. Messina; R. Passante

2009-03-18T23:59:59.000Z

336

A New Method to Reconstruct the Energy and Determine the Composition of Cosmic Rays from the Measurement of Cherenkov Light and Particle Densities in Extensive Air Showers  

E-Print Network [OSTI]

A Monte-Carlo study to reconstruct energy and mass of cosmic rays with energies above 300 TeV using ground based measurements of the electromagnetic part of showers initiated in the atmosphere is presented. The shower properties determined with two detector arrays measuring the air Cherenkov light and the particle densities as realized at the HEGRA experiment are processed to determine the energy of the primary particle without the need of any hypothesis concerning its mass. The mass of the primary particle is reconstructed coarsely from the same observables in parallel to the energy determination.

A. Lindner

1998-01-15T23:59:59.000Z

337

Rotational properties of nuclei around $^{254}$No investigated using a spectroscopic-quality Skyrme energy density functional  

E-Print Network [OSTI]

Nuclei in the $Z\\approx100$ mass region represent the heaviest systems where detailed spectroscopic information is experimentally available. Although microscopic-macroscopic and self-consistent models have achieved great success in describing the data in this mass region, a fully satisfying precise theoretical description is still missing. By using fine-tuned parametrizations of the energy density functionals, the present work aims at an improved description of the single-particle properties and rotational bands in the nobelium region. Such locally optimized parameterizations may have better properties when extrapolating towards the superheavy region. Skyrme-Hartree-Fock-Bogolyubov and Lipkin-Nogami methods were used to calculate the quasiparticle energies and rotational bands of nuclei in the nobelium region. Starting from the most recent Skyrme parametrization, UNEDF1, the spin-orbit coupling constants and pairing strengths have been tuned, so as to achieve a better agreement with the excitation spectra and odd-even mass differences in $^{251}$Cf and $^{249}$Bk. The quasiparticle properties of $^{251}$Cf and $^{249}$Bk were very well reproduced. At the same time, crucial deformed neutron and proton shell gaps open up at $N=152$ and $Z=100$, respectively. Rotational bands in Fm, No, and Rf isotopes, where experimental data are available, were also fairly well described. To help future improvements towards a more precise description, small deficiencies of the approach were carefully identified. In the $Z\\approx100$ mass region, larger spin-orbit strengths than those from global adjustments lead to improved agreement with data. Puzzling effects of particle-number restoration on the calculated moment of inertia, at odds with the experimental behaviour, require further scrutiny.

Yue Shi; J. Dobaczewski; P. T. Greenlees

2013-12-16T23:59:59.000Z

338

Strain energy density-distance criterion for the initiation of stress corrosion cracking of alloy X-750  

SciTech Connect (OSTI)

A strain energy density-distance criterion was previously developed and used to correlate rising-load K{sub c} initiation data for notched and fatigue precracked specimens of hydrogen precharged Alloy X-750. This criterion, which was developed for hydrogen embrittlement (HE) cracking, is used here to correlate static-load stress corrosion cracking (SCC) initiation times obtained for smooth geometry, notched and fatigue precracked specimens. The onset of SCC crack growth is hypothesized to occur when a critical strain, which is due to environment-enhanced creep, is attained within the specimen interior. For notched and precracked specimens, initiation is shown by analysis to occur at a variable distance from notch and crack tips. The initiation site varies from very near the crack tip, for highly loaded sharp cracks, to a site that is one grain diameter from the notch, for lower loaded, blunt notches. The existence of hydrogen gradients, which are due to strain-induced hydrogen trapping in the strain fields of notch and crack tips, is argued to be controlling the site for initiation of cracking. By considering the sources of the hydrogen, these observations are shown to be consistent with those from the previous HE study, in which the characteristic distance for crack initiation was found to be one grain diameter from the notch tip, independent of notch radius, applied stress intensity factor and hydrogen level.

Hall, M.M. Jr.; Symons, D.M.

1996-05-01T23:59:59.000Z

339

Nano-sized structured layered positive electrode materials to enable high energy density and high rate capability lithium batteries  

DOE Patents [OSTI]

Nano-sized structured dense and spherical layered positive active materials provide high energy density and high rate capability electrodes in lithium-ion batteries. Such materials are spherical second particles made from agglomerated primary particles that are Li.sub.1+.alpha.(Ni.sub.xCo.sub.yMn.sub.z).sub.1-tM.sub.tO.sub.2-dR.sub.d- , where M is selected from can be Al, Mg, Fe, Cu, Zn, Cr, Ag, Ca, Na, K, In, Ga, Ge, V, Mo, Nb, Si, Ti, Zr, or a mixture of any two or more thereof, R is selected from F, Cl, Br, I, H, S, N, or a mixture of any two or more thereof, and 0.ltoreq..alpha..ltoreq.0.50; 0

Deng, Haixia; Belharouak, Ilias; Amine, Khalil

2012-10-02T23:59:59.000Z

340

Low-momentum interactions with Brown-Rho-Ericson scalings and the density dependence of the nuclear symmetry energy  

E-Print Network [OSTI]

We have calculated the nuclear symmetry energy $E_{sym}(\\rho)$ up to densities of $4 \\sim 5 \\rho_0$ with the effects from the Brown-Rho (BR) and Ericson scalings for the in-medium mesons included. Using the $V_{low-k}$ low-momentum interaction with and without such scalings, the equations of state (EOS) of symmetric and asymmetric nuclear matter have been calculated using a ring-diagarm formalism where the particle-particle-hole-hole ring diagrams are included to all orders. The EOS for symmetric nuclear matter and neutron matter obtained with linear BR scaling are both overly stiff compared with the empirical constraints of Danielewicz {\\it et al.} \\cite{daniel02}. In contrast, satisfactory results are obtained by either using the nonlinear Ericson scaling or by adding a Skyrme-type three-nucleon force (TNF) to the unscaled $V_{low-k}$ interaction. Our results for $E_{sym}(\\rho)$ obtained with the nonlinear Ericson scaling are in good agreement with the empirical values of Tsang {\\it et al.} \\cite{tsang09} a...

Dong, Huan; Machleidt, R

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

AlGaN UV LED and Photodiodes Radiation Hardness and Space Qualifications and Their Applications in Space Science and High Energy Density Physics  

SciTech Connect (OSTI)

This presentation provides an overview of robust, radiation hard AlGaN optoelectronic devices and their applications in space exploration & high energy density physics. Particularly, deep UV LED and deep UV photodiodes are discussed with regard to their applications, radiation hardness and space qualification. AC charge management of UV LED satellite payload instruments, which were to be launched in late 2012, is covered.

Sun, K. X.

2011-05-31T23:59:59.000Z

342

A study of density of states and ground states in hydrophobic-hydrophilic protein folding models by equi-energy sampling  

E-Print Network [OSTI]

A study of density of states and ground states in hydrophobic-hydrophilic protein folding models June 2006 We propose an equi-energy EE sampling approach to study protein folding in the two a detailed study of the thermodynamics of HP protein folding, in particular, on the temperature dependence

Kou, Samuel

343

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

SciTech Connect (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

344

Gedanken densities and exact constraints in density functional theory  

SciTech Connect (OSTI)

Approximations to the exact density functional for the exchange-correlation energy of a many-electron ground state can be constructed by satisfying constraints that are universal, i.e., valid for all electron densities. Gedanken densities are designed for the purpose of this construction, but need not be realistic. The uniform electron gas is an old gedanken density. Here, we propose a spherical two-electron gedanken density in which the dimensionless density gradient can be an arbitrary positive constant wherever the density is non-zero. The Lieb-Oxford lower bound on the exchange energy can be satisfied within a generalized gradient approximation (GGA) by bounding its enhancement factor or simplest GGA exchange-energy density. This enhancement-factor bound is well known to be sufficient, but our gedanken density shows that it is also necessary. The conventional exact exchange-energy density satisfies no such local bound, but energy densities are not unique, and the simplest GGA exchange-energy density is not an approximation to it. We further derive a strongly and optimally tightened bound on the exchange enhancement factor of a two-electron density, which is satisfied by the local density approximation but is violated by all published GGA's or meta-GGA’s. Finally, some consequences of the non-uniform density-scaling behavior for the asymptotics of the exchange enhancement factor of a GGA or meta-GGA are given.

Perdew, John P. [Department of Physics, Temple University, Philadelphia, Pennsylvania 19122 (United States) [Department of Physics, Temple University, Philadelphia, Pennsylvania 19122 (United States); Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122 (United States); Ruzsinszky, Adrienn; Sun, Jianwei [Department of Physics, Temple University, Philadelphia, Pennsylvania 19122 (United States)] [Department of Physics, Temple University, Philadelphia, Pennsylvania 19122 (United States); Burke, Kieron [Department of Chemistry and Department of Physics, University of California, Irvine, California 92697 (United States)] [Department of Chemistry and Department of Physics, University of California, Irvine, California 92697 (United States)

2014-05-14T23:59:59.000Z

345

Co3O4 nanocubes homogeneously assembled on few-layer graphene for high energy density lithium-ion batteries  

Science Journals Connector (OSTI)

Abstract Graphene-based nanocomposites have been synthesized and tested as electrode materials for high power lithium-ion batteries. In the synthesis of such nanocomposites, graphene is generally introduced by either thermally or chemically reduced graphite oxide (GO), which has poorer electric conductivity and crystallinity than mechanically exfoliated graphene. Here, we prepare few-layer graphene sheet (FLGS) with high electric conductivity, by sonicating expanded graphite in DMF solvent, and develop a simple one-pot hydrothermal method to fabricate monodispersed and ultrasmall Co3O4 nanocubes (about 4 nm in size) on the FLGS. This composite, consisting of homogeneously assembled and high crystalline Co3O4 nanocubes on the FLGS, has shown higher capacity and much better cycling stability than counterparts synthesized using GO as a precursor. The products in different synthesis stages have been characterized by TEM, FTIR and XPS to investigate the nanocube growth mechanism. We find that Co(OH)2 initially grew homogeneously on the graphene surface, then gradually oxidized to form Co3O4 nanoparticle seeds, and finally converted to Co3O4 nanocubes with caboxylated anion as surfactant. This work explores the mechanism of nanocrystal growth and its impact on electrochemical properties to provide further insights into the development of nanostructured electrode materials for high power energy storage.

Junming Xu; Jinsong Wu; Langli Luo; Xinqi Chen; Huibin Qin; Vinayak Dravid; Shaobo Mi; Chunlin Jia

2015-01-01T23:59:59.000Z

346

Hard TiCx/SiC/a-C:H nanocomposite thin films using pulsed high energy density plasma focus device  

Science Journals Connector (OSTI)

Abstract Thin films of TiCx/SiC/a-C:H were synthesized on Si substrates using a complex mix of high energy density plasmas and instability accelerated energetic ions of filling gas species, emanated from hot and dense pinched plasma column, in dense plasma focus device. The conventional hollow copper anode of Mather type plasma focus device was replaced by solid titanium anode for synthesis of TiCx/SiC/a-C:H nanocomposite thin films using CH4:Ar admixture of (1:9, 3:7 and 5:5) for fixed 20 focus shots as well as with different number of focus shots with fixed CH4:Ar admixture ratio 3:7. XRD results showed the formation of crystalline TiCx/SiC phases for thin film synthesized using different number of focus shots with CH4:Ar admixture ratio fixed at 3:7. SEM results showed that the synthesized thin films consist of nanoparticle agglomerates and the size of agglomerates depended on the CH4:Ar admixture ratio as well as on the number of focus shots. Raman analysis showed the formation of polycrystalline/amorphous Si, SiC and a-C for different CH4:Ar ratio as well as for different number of focus shots. The XPS analysis confirmed the formation of TiCx/SiC/a-C:H composite thin film. Nanoindentation results showed that the hardness and elastic modulus values of composite thin films increased with increasing number of focus shots. Maximum values of hardness and elastic modulus at the surface of the composite thin film were found to be about 22 and 305 GPa, respectively for 30 focus shots confirming the successful synthesis of hard composite TiCx/SiC/a-C:H coatings.

Z.A. Umar; R.S. Rawat; K.S. Tan; A.K. Kumar; R. Ahmad; T. Hussain; C. Kloc; Z. Chen; L. Shen; Z. Zhang

2013-01-01T23:59:59.000Z

347

Symmetry Energy  

E-Print Network [OSTI]

Examination of symmetry energy is carried out on the basis of an elementary binding-energy formula. Constraints are obtained on the energy value at the normal nuclear density and on the density dependence of the energy at subnormal densities.

P. Danielewicz

2006-07-15T23:59:59.000Z

348

Symmetry Energy  

E-Print Network [OSTI]

Examination of symmetry energy is carried out on the basis of an elementary binding-energy formula. Constraints are obtained on the energy value at the normal nuclear density and on the density dependence of the energy at subnormal densities.

Danielewicz, P

2006-01-01T23:59:59.000Z

349

Thermochemical process for seasonal storage of solar energy: characterization and modeling of a high-density reactive bed  

E-Print Network [OSTI]

1 Thermochemical process for seasonal storage of solar energy: characterization and modeling to maximize the use of solar energy for house heating, it is interesting to valorize the solar energy excess efficiency, and a 20 per cent share of renewable). The use of renewable energies and in particular solar

Paris-Sud XI, Université de

350

Optimization of cylindrical composite flywheel rotors for energy storage  

Science Journals Connector (OSTI)

We hope that our efforts will contribute towards the design of flywheel rotors that have higher energy densities and ... that this can contribute to a future electricity grid that can accommodate renewable energy...

Petrus J. Janse van Rensburg…

2013-01-01T23:59:59.000Z

351

Optimization towards high density quantum dots for intermediate band solar cells grown by molecular beam epitaxy  

SciTech Connect (OSTI)

We report high density quantum dots (QDs) formation with optimized growth temperature and V/III ratio. At lower growth temperature, QD density is increased, due to smaller surface migration length of In adatoms. With higher V/III, the QD density is higher but it results in large clusters formation and decreases the QD uniformity. The QD solar cell was fabricated and examined. An extended spectral response in contrast to the GaAs reference cell was presented but the external quantum efficiency at energies higher than GaAs band gap is reduced, resulting from the degradation for the emitter above the strained QD layers.

Zhou, D.; Sharma, G.; Fimland, B. O. [Department of Electronics and Telecommunications, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway); Thomassen, S. F.; Reenaas, T. W. [Department of Physics, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway)

2010-02-08T23:59:59.000Z

352

Conversion of the energy-subtracted CT number to electron density based on a single linear relationship: an experimental verification using a clinical dual-source CT scanner  

Science Journals Connector (OSTI)

In radiotherapy treatment planning, the conversion of the computed tomography (CT) number to electron density is one of the main processes that determine the accuracy of patient dose calculations. However, in general, the CT number and electron density of tissues cannot be interrelated using a simple one-to-one correspondence. This study aims to experimentally verify the clinical feasibility of an existing novel conversion method proposed by the author of this note, which converts the energy-subtracted CT number (?HU) to the relative electron density (?e) via a single linear relationship by using a dual-energy CT (DECT). The ?HU–?e conversion was performed using a clinical second-generation dual-source CT scanner operated in the dual-energy mode with tube potentials of 80 kV and 140 kV with and without an additional tin filter. The ?HU–?e calibration line was obtained from the DECT image acquisition for tissue substitutes in an electron density phantom. In addition, the effect of object size on ?HU–?e conversion was also experimentally investigated. The plot of the measured ?HU versus nominal ?e values exhibited a single linear relationship over a wide ?e range from 0.00 (air) to 2.35 (aluminum). The ?HU–?e conversion performed with the tin filter yielded a lower dose and more reliable ?e values that were less affected by the object-size variation when compared to the corresponding values obtained for the case without the tin filter.

Masayoshi Tsukihara; Yoshiyuki Noto; Takahide Hayakawa; Masatoshi Saito

2013-01-01T23:59:59.000Z

353

Excitation energies with linear response density matrix functional theory along the dissociation coordinate of an electron-pair bond in N-electron systems  

SciTech Connect (OSTI)

Time dependent density matrix functional theory in its adiabatic linear response formulation delivers exact excitation energies ?{sub ?} and oscillator strengths f{sub ?} for two-electron systems if extended to the so-called phase including natural orbital (PINO) theory. The Löwdin-Shull expression for the energy of two-electron systems in terms of the natural orbitals and their phases affords in this case an exact phase-including natural orbital functional (PILS), which is non-primitive (contains other than just J and K integrals). In this paper, the extension of the PILS functional to N-electron systems is investigated. With the example of an elementary primitive NO functional (BBC1) it is shown that current density matrix functional theory ground state functionals, which were designed to produce decent approximations to the total energy, fail to deliver a qualitatively correct structure of the (inverse) response function, due to essential deficiencies in the reconstruction of the two-body reduced density matrix (2RDM). We now deduce essential features of an N-electron functional from a wavefunction Ansatz: The extension of the two-electron Löwdin-Shull wavefunction to the N-electron case informs about the phase information. In this paper, applications of this extended Löwdin-Shull (ELS) functional are considered for the simplest case, ELS(1): one (dissociating) two-electron bond in the field of occupied (including core) orbitals. ELS(1) produces high quality ?{sub ?}(R) curves along the bond dissociation coordinate R for the molecules LiH, Li{sub 2}, and BH with the two outer valence electrons correlated. All of these results indicate that response properties are much more sensitive to deficiencies in the reconstruction of the 2RDM than the ground state energy, since derivatives of the functional with respect to both the NOs and the occupation numbers need to be accurate.

Meer, R. van; Gritsenko, O. V. [Faculty of Exact Sciences, Theoretical Chemistry, VU University, Amsterdam (Netherlands) [Faculty of Exact Sciences, Theoretical Chemistry, VU University, Amsterdam (Netherlands); WCU Program, Dep. of Chemistry, Pohang Univ. of Science and Techn., Pohang (Korea, Republic of); Baerends, E. J. [Faculty of Exact Sciences, Theoretical Chemistry, VU University, Amsterdam (Netherlands) [Faculty of Exact Sciences, Theoretical Chemistry, VU University, Amsterdam (Netherlands); WCU Program, Dep. of Chemistry, Pohang Univ. of Science and Techn., Pohang (Korea, Republic of); Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)

2014-01-14T23:59:59.000Z

354

Carrier Density and Compensation in Semiconductors with Multi Dopants and Multi Transition Energy Levels: The Case of Cu Impurity in CdTe: Preprint  

SciTech Connect (OSTI)

Doping is one of the most important issues in semiconductor physics. The charge carrier generated by doping can profoundly change the properties of semiconductors and their performance in optoelectronic device applications, such as solar cells. Using detailed balance theory and first-principles calculated defect formation energies and transition energy levels, we derive general formulae to calculate carrier density for semiconductors with multi dopants and multi transition energy levels. As an example, we studied CdTe doped with Cu, in which VCd, CuCd, and Cui are the dominant defects/impurities. We show that in this system, when Cu concentration increases, the doping properties of the system can change from a poor p-type, to a poorer p-type, to a better p-type, and then to a poor p-type again, in good agreement with experimental observation of CdTe-based solar cells.

Wei, S. H.; Ma, J.; Gessert, T. A.; Chin, K. K.

2011-07-01T23:59:59.000Z

355

Flow at Brookhaven AGS Energy (11.6 GeV/nucleon): A barometer for high density effects?  

SciTech Connect (OSTI)

Preliminary data on transverse energy {open_quotes}flow{close_quotes} and event asymmetries reported by the E877(814) Collaborations are compared to ARC (a relativistic cascade) model calculations for Au+Au at full AGS Brookhaven (Alternating Gradient Synchroton) beam energy. ARC triple differential cross sections for protons and pions are presented. Proton flow is produced in ARC, with the maximum {l_angle}P{sub x}{r_angle}{approximately}120 MeV/c. For central events {l_angle}P{sub x}{r_angle} for the pions is near zero, consistent with experiment. The comparison with data provides a constraint on the size of flow at the highest energy available, to be put beside that at Bevalac energy. This sets the stage for examining flow at intermediate energies, now being measured by E895, for signs of baryon rich plasma. {copyright} {ital 1997} {ital The American Physical Society}

Kahana, D.E.; Shuryak, E. [Department of Physics, State University of New York, Stony Brook, New York 11791 (United States)] [Department of Physics, State University of New York, Stony Brook, New York 11791 (United States); Pang, Y. [Department of Physics, Brookhaven National Laboratory, Upton, New York 11973 (United States)] [Department of Physics, Brookhaven National Laboratory, Upton, New York 11973 (United States); Pang, Y. [Department of Physics, Columbia University, New York, New York 10027 (United States)] [Department of Physics, Columbia University, New York, New York 10027 (United States)

1997-07-01T23:59:59.000Z

356

Neutron Matter from Low to High Density  

E-Print Network [OSTI]

Neutron matter is an intriguing nuclear system with multiple connections to other areas of physics. Considerable progress has been made over the last two decades in exploring the properties of pure neutron fluids. Here we begin by reviewing work done to explore the behavior of very low density neutron matter, which forms a strongly paired superfluid and is thus similar to cold Fermi atoms, though at energy scales differing by many orders of magnitude. We then increase the density, discussing work that ties the study of neutron matter with the determination of the properties of neutron-rich nuclei and neutron-star crusts. After this, we review the impact neutron matter at even higher densities has on the mass-radius relation of neutron stars, thereby making contact with astrophysical observations.

Gandolfi, Stefano; Carlson, J

2015-01-01T23:59:59.000Z

357

Ab initio-driven nuclear energy density functional method. A proposal for safe/correlated/improvable parametrizations of the off-diagonal EDF kernels  

E-Print Network [OSTI]

This programmatic paper lays down the possibility to reconcile the necessity to resum many-body correlations into the energy kernel with the fact that safe multi-reference energy density functional (EDF) calculations cannot be achieved whenever the Pauli principle is not strictly enforced, as is for example the case when many-body correlations are parametrized under the form of empirical density dependencies. Our proposal is to exploit a newly developed ab initio many-body formalism to guide the construction of safe, explicitly correlated and systematically improvable parametrizations of the {\\it off-diagonal} energy and norm kernels that lie at the heart of the nuclear EDF method. The many-body formalism of interest relies on the concepts of symmetry breaking {\\it and} restoration that have made the fortune of the nuclear EDF method and is, as such, amenable to this guidance. After elaborating on our proposal, we briefly outline the project we plan to execute in the years to come.

Duguet, T; Ebran, J -P; Lesinski, T; Somà, V

2015-01-01T23:59:59.000Z

358

Developing "BUILDING/ FACILITY ENERGY CONSUMPTION DATA SHEET" for Political Subdivisions, Institutions of Higher Education, and State Agencies, to Satisfy Senate Bill 898 (82nd R) Reporting Requirements  

E-Print Network [OSTI]

, the amount of energy savings and estimated reduction in pollution achieved as a result of the implementation of the programs, and then provide the information to the Texas Commission on Environmental Quality, the United States Environmental Protection Agency...

Parker, P.; Baltazar, J.; Haberl, J.; Yazdani, B.; Zilbershtein, G.

2012-01-01T23:59:59.000Z

359

Estimation of the electron density and radiative energy losses in a calcium plasma source based on an electron cyclotron resonance discharge  

SciTech Connect (OSTI)

The parameters of a calcium plasma source based on an electron cyclotron resonance (ECR) discharge were calculated. The analysis was performed as applied to an ion cyclotron resonance system designed for separation of calcium isotopes. The plasma electrons in the source were heated by gyrotron microwave radiation in the zone of the inhomogeneous magnetic field. It was assumed that, in such a combined trap, the energy of the extraordinary microwave propagating from the high-field side was initially transferred to a small group of resonance electrons. As a result, two electron components with different transverse temperatures-the hot resonance component and the cold nonresonance component-were created in the plasma. The longitudinal temperatures of both components were assumed to be equal. The entire discharge space was divided into a narrow ECR zone, where resonance electrons acquired transverse energy, and the region of the discharge itself, where the gas was ionized. The transverse energy of resonance electrons was calculated by solving the equations for electron motion in an inhomogeneous magnetic field. Using the law of energy conservation and the balance condition for the number of hot electrons entering the discharge zone and cooled due to ionization and elastic collisions, the density of hot electrons was estimated and the dependence of the longitudinal temperature T{sub e Parallel-To} of the main (cold) electron component on the energy fraction {beta} lost for radiation was obtained.

Potanin, E. P., E-mail: potanin@imp.kiae.ru; Ustinov, A. L. [National Research Centre Kurchatov Institute (Russian Federation)

2013-06-15T23:59:59.000Z

360

Ris Energy Report 5 New and emerging technologies for renewable energy 51 in the transport sector  

E-Print Network [OSTI]

. Energy densities of different energy storage systems. The num- bers are based on higher heats produce their energy mainly in the form of electricity. This means that if we want to decouple trans- port from the use of fossil fuels, we must find ways to use electric energy in vehicles. Electric trains

Note: This page contains sample records for the topic "higher energy 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

Density Functional Theory for Fractional Particle Number: Derivative Discontinuity of the Energy at the Maximum Number of Bound Electrons  

E-Print Network [OSTI]

The derivative discontinuity in the exact exchange-correlation potential of ensemble Density Functional Theory (DFT) is investigated at the specific integer number that corresponds to the maximum number of bound electrons, $J_{max}$. A recently developed complex-scaled analog of DFT is extended to fractional particle numbers and used to study ensembles of both bound and metastable states. It is found that the exact exchange-correlation potential experiences discontinuous jumps at integer particle numbers including $J_{max}$. For integers below $J_{max}$ the jump is purely real because of the real shift in the chemical potential. At $J_{max}$, the jump has a non-zero imaginary component reflecting the finite lifetime of the $(J_{max}+1)$ state.

Daniel L. Whitenack; Yu Zhang; Adam Wasserman

2011-11-08T23:59:59.000Z

362

Impact of the energy loss spatial profile and shear viscosity to entropy density ratio for the Mach cone vs. head shock signals produced by a fast moving parton in a quark-gluon plasma  

E-Print Network [OSTI]

We compute the energy and momentum deposited by a fast moving parton in a quark-gluon plasma using linear viscous hydrodynamics with an energy loss per unit length profile proportional to the path length and with different values of the shear viscosity to entropy density ratio. We show that when varying these parameters, the transverse modes still dominate over the longitudinal ones and thus energy and momentum is preferentially deposited along the head-shock, as in the case of a constant energy loss per unit length profile and the lowest value for the shear viscosity to entropy density ratio.

Alejandro Ayala; Jorge David Castano-Yepes; Isabel Dominguez; Maria Elena Tejeda-Yeomans

2014-12-18T23:59:59.000Z

363

Megatrends in Higher Education.  

E-Print Network [OSTI]

??Utilizing the theory of John Naisbitt's 1982 Megatrends, this study identifies eight trends for the future of higher education using content analysis of generalized print… (more)

Smith, Shannon Tucker

2008-01-01T23:59:59.000Z

364

Higher Education in Scandinavia.  

E-Print Network [OSTI]

??Higher education systems around the world have been undergoing fundamental changes through the last 50 years from more narrow self-sustaining universities for the elite and… (more)

Birch Andreasen, Lars

2015-01-01T23:59:59.000Z

365

A Low-cost, High-yield Process for the Direct Productin of High Energy Density Liquid Fuel from Biomass  

SciTech Connect (OSTI)

The primary objective and outcome of this project was the development and validation of a novel, low-cost, high-pressure fast-hydropyrolysis/hydrodeoxygenation (HDO) process (H{sub 2}Bioil) using supplementary hydrogen (H{sub 2}) to produce liquid hydrocarbons from biomass. The research efforts under the various tasks of the project have culminated in the first experimental demonstration of the H2Bioil process, producing 100% deoxygenated >C4+ hydrocarbons containing 36-40% of the carbon in the feed of pyrolysis products from biomass. The demonstrated H{sub 2}Bioil process technology (i.e. reactor, catalyst, and downstream product recovery) is scalable to a commercial level and is estimated to be economically competitive for the cases when supplementary H{sub 2} is sourced from coal, natural gas, or nuclear. Additionally, energy systems modeling has revealed several process integration options based on the H{sub 2}Bioil process for energy and carbon efficient liquid fuel production. All project tasks and milestones were completed or exceeded. Novel, commercially-scalable, high-pressure reactors for both fast-hydropyrolysis and hydrodeoxygenation were constructed, completing Task A. These reactors were capable of operation under a wide-range of conditions; enabling process studies that lead to identification of optimum process conditions. Model compounds representing biomass pyrolysis products were studied, completing Task B. These studies were critical in identifying and developing HDO catalysts to target specific oxygen functional groups. These process and model compound catalyst studies enabled identification of catalysts that achieved 100% deoxygenation of the real biomass feedstock, sorghum, to form hydrocarbons in high yields as part of Task C. The work completed during this grant has identified and validated the novel and commercially scalable H2Bioil process for production of hydrocarbon fuels from biomass. Studies on model compounds as well as real biomass feedstocks were utilized to identify optimized process conditions and selective HDO catalyst for high yield production of hydrocarbons from biomass. In addition to these experimental efforts, in Tasks D and E, we have developed a mathematical optimization framework to identify carbon and energy efficient biomass-to-liquid fuel process designs that integrate the use of different primary energy sources along with biomass (e.g. solar, coal or natural gas) for liquid fuel production. Using this tool, we have identified augmented biomass-to-liquid fuel configurations based on the fast-hydropyrolysis/HDO pathway, which was experimentally studied in this project. The computational approach used for screening alternative process configurations represents a unique contribution to the field of biomass processing for liquid fuel production.

Agrawal, Rakesh

2014-02-21T23:59:59.000Z

366

Monochromatic x-ray radiography for areal-density measurement of inertial fusion energy fuel in fast ignition experiment  

SciTech Connect (OSTI)

Ultrafast, two-dimensional x-ray imaging is an important diagnostics for the inertial fusion energy research, especially in investigating implosion dynamics at the final stage of the fuel compression. Although x-ray radiography was applied to observing the implosion dynamics, intense x-rays emitted from the high temperature and dense fuel core itself are often superimposed on the radiograph. This problem can be solved by coupling the x-ray radiography with monochromatic x-ray imaging technique. In the experiment, 2.8 or 5.2 keV backlight x-rays emitted from laser-irradiated polyvinyl chloride or vanadium foils were selectively imaged by spherically bent quartz crystals with discriminating the out-of-band emission from the fuel core. This x-ray radiography system achieved 24 {mu}m and 100 ps of spatial and temporal resolutions, respectively.

Fujioka, Shinsuke; Fujiwara, Takashi; Tanabe, Minoru; Nishimura, Hiroaki; Nagatomo, Hideo; Ohira, Shinji; Shiraga, Hiroyuki; Azechi, Hiroshi [Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita Osaka, 565-0871 (Japan); Inubushi, Yuichi [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

2010-10-15T23:59:59.000Z

367

Studies of heavy ion-induced high-energy density states in matter at the GSI Darmstadt SIS-18 and future FAIR facility  

Science Journals Connector (OSTI)

This paper presents numerical simulation results of heating and compression of matter using intense beams of energetic heavy ions. In this study we consider different beam parameters that include those which are currently available at the heavy ion synchrotron, SIS18 at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt and those which will be available in the near future as a result of the upgraded facility. In addition to this, we carried out detailed calculations considering parameters of high-intensity beam which will be generated at the GSI future Facility for Antiprotons and Ion Research (FAIR facility) that has been approved by the German Government. These simulations show that by using the above ion beam parameter range, it will be possible to carry out very useful studies on the thermophysical properties of high-energy density (HED) states in matter. This scheme would make it possible to investigate those regions of the phase diagram that are either very difficult to access or even are unaccessible using the traditional methods of shock waves. Moreover, employing a hollow ion beam which has an annular (ring shaped) focal spot, it would be possible to achieve a low entropy compression of a test material like hydrogen, which is enclosed in a cylindrical shell of a high-density material such as lead or gold. These experiments will enable one to study the interiors of Giant planets, Jupiter and Saturn as well as to investigate the problem of hydrogen metallization.

N.A. Tahir; A. Adonin; C. Deutsch; V.E. Fortov; N. Grandjouan; B. Geil; V. Grayaznov; D.H.H. Hoffmann; M. Kulish; I.V. Lomonosov; V. Mintsev; P. Ni; D. Nikolaev; A.R. Piriz; N. Shilkin; P. Spiller; A. Shutov; M. Temporal; V. Ternovoi; S. Udrea; D. Varentsov

2005-01-01T23:59:59.000Z

368

Proposal for the Study of Thermophysical Properties of High-Energy-Density Matter Using Current and Future Heavy-Ion Accelerator Facilities at GSI Darmstadt  

Science Journals Connector (OSTI)

The subject of high-energy-density (HED) states in matter is of considerable importance to numerous branches of basic as well as applied physics. Intense heavy-ion beams are an excellent tool to create large samples of HED matter in the laboratory with fairly uniform physical conditions. Gesellschaft für Schwerionenforschung, Darmstadt, is a unique worldwide laboratory that has a heavy-ion synchrotron, SIS18, that delivers intense beams of energetic heavy ions. Construction of a much more powerful synchrotron, SIS100, at the future international facility for antiprotons and ion research (FAIR) at Darmstadt will lead to an increase in beam intensity by 3 orders of magnitude compared to what is currently available. The purpose of this Letter is to investigate with the help of two-dimensional numerical simulations, the potential of the FAIR to carry out research in the field of HED states in matter.

N. A. Tahir, C. Deutsch, V. E. Fortov, V. Gryaznov, D. H. H. Hoffmann, M. Kulish, I. V. Lomonosov, V. Mintsev, P. Ni, D. Nikolaev, A. R. Piriz, N. Shilkin, P. Spiller, A. Shutov, M. Temporal, V. Ternovoi, S. Udrea, and D. Varentsov

2005-07-11T23:59:59.000Z

369

Teknik och social frndring Higher Seminar  

E-Print Network [OSTI]

ambition to shape the transition towards sustainable energy systems. All welcome! Tema T higher seminar and Social change "Transforming energy systems: a socio-tecnical perspective" Innovation and technology the challenge of transforming energy systems towards greater sustainability. I will, however, also focus

Zhao, Yuxiao

370

Higher Dimensional Elko Theory  

E-Print Network [OSTI]

We show that the so called Elko equation can be derived from a 5-dimensional Dirac equation. We argue that this result can be relevant for dark matter and cosmological scenarios. We generalize our procedure to higher dimensions.

J. A. Nieto

2014-07-07T23:59:59.000Z

371

Latent Heat or Phase Change Thermal Energy Storage  

Science Journals Connector (OSTI)

It has been explained in sections 1.6 and 1.6.2 how phase change materials (PCM) have considerably higher thermal energy storage densities compared to sensible heat storage materials and are able to absorb or rel...

H. P. Garg; S. C. Mullick; A. K. Bhargava

1985-01-01T23:59:59.000Z

372

Impact of Baryonic Processes on Weak Lensing Cosmology: Higher-Order Statistics and Parameter Bias  

E-Print Network [OSTI]

We study the impact of baryonic physics on cosmological parameter estimation with weak lensing surveys. We run a set of cosmological hydrodynamics simulations with different galaxy formation models. We then perform ray-tracing simulations through the total matter density field to generate 100 independent convergence maps of 25 deg$^2$ field-of-view, and use them to examine the ability of the following three lensing statistics as cosmological probes; power spectrum, peak counts, and Minkowski Functionals. For the upcoming wide-field observations such as Subaru Hyper Suprime-Cam (HSC) survey with a sky coverage of 1400 deg$^2$, the higher-order statistics provide tight constraints on the matter density, density fluctuation amplitude, and dark energy equation of state, but appreciable parameter bias is induced by the baryonic processes such as gas cooling and stellar feedback. When we use power spectrum, peak counts, and Minkowski Functionals, the relative bias in the dark energy equation of state parameter $w$ ...

Osato, Ken; Yoshida, Naoki

2015-01-01T23:59:59.000Z

373

Page not found | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

11 - 9220 of 26,764 results. 11 - 9220 of 26,764 results. Download CX-006506: Categorical Exclusion Determination Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500 Watthours per Liter CX(s) Applied: B3.6 Date: 08/25/2011 Location(s): Oak Ridge, Tennessee Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-006506-categorical-exclusion-determination Download CX-006507: Categorical Exclusion Determination Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500 Watthours per Liter CX(s) Applied: B3.6 Date: 08/25/2011 Location(s): Lee's Summit, Missouri Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory http://energy.gov/nepa/downloads/cx-006507-categorical-exclusion-determination

374

Title of Document: LONGITUDINAL SPACE-CHARGE WAVES INDUCED BY ENERGY MODULATIONS  

E-Print Network [OSTI]

ABSTRACT Title of Document: LONGITUDINAL SPACE-CHARGE WAVES INDUCED BY ENERGY MODULATIONS Brian L. Modulations in energy or density can induce space-charge waves at low energies which could be problematic at higher energies. This thesis is a study of longitudinal space-charge waves induced by energy modulations

Anlage, Steven

375

r- and p-space electron densities and related kinetic and exchange energies in terms of s states alone for the leading term in the 1/Z expansion for nonrelativistic closed-shell atomic ions  

Science Journals Connector (OSTI)

As a step towards constructing nonlocal energy density functionals, the leading term in the so-called 1/Z expansion for closed-shell atomic ions is the focus here. This term is characterized by the properties of the bare Coulomb potential (-Ze2/r), and for an arbitrary number of closed shells it is known that ??(r)/?r=-(2Z/a0)?s(r), where ?(r) is the ground-state electron density while ?s(r) is the s-state (l=0) contribution to ?(r). Here, the kinetic-energy density t(r) is also derived as a double integral in terms of ?s(r) and Z. Although the exchange energy density ?x(r) is more complex than t(r), a proof is given that, in the Coulomb limit system, ?x is indeed also determined by s-state properties alone. The same is shown to be true for the momentum density n(p), which here is obtained explicitly for an arbitrary number of closed shells. Finally, numerical results are presented that include (a) ten-electron atomic ions (K+L shells), (b) the limit as the number of closed shells tends to infinity, where an appeal is made to the analytical r-space study of Heilmann and Lieb [Phys. Rev. A 52, 3628 (1995)], and (c) momentum density and Compton line shape for an arbitrary number of closed shells.

I. A. Howard; N. H. March; V. E. Van Doren

2001-05-04T23:59:59.000Z

376

The analytical energy gradient scheme in the Gaussian based Hartree-Fock and density functional theory for two-dimensional systems using fast multipole method  

SciTech Connect (OSTI)

The analytical total energy gradient scheme for the Hartree-Fock and density functional crystalline orbital theory is formulated for infinitely extended periodic systems of general dimensions and implemented for those of two dimensions. Two major differences between the analytical gradient scheme for extended systems and that for molecular systems are described in detail. The first is the treatment of the long-range Coulomb interactions, which arises due to the infinite nature of the systems. The long-range effect is efficiently included by the multipole expansion technique and its extension, the fast multipole method The use of the fast multipole method enables us to include the long range effect up to the order of micro meter to millimeter region around the reference unit cell by virtue of the logarithmic cost scaling of the algorithm achieved by regrouping distant multipoles together and reducing the number of pairwise interactions. The second is the formulation of analytical gradient expressions with respect to unit cell parameters. In the HF theory they can be calculated by accumulating forces acting on atoms multiplied by some appropriate factors, while there is an extra term which requires a special numerical treatment in grid-based density functional theory. Specifically, it is shown that the quadrature weight derivatives do not vanish even in the limit of infinitely fine grid, when calculating the gradients with respect to unit cell parameters, and are essential in evaluating those gradients. Combining the analytical gradient scheme and an efficient inclusion of the long-range interaction makes it feasible to perform a full geometry optimization of extended systems at ab initio levels.

Tobita, Motoi; Hirata, So; Bartlett, Rodney J.

2003-04-01T23:59:59.000Z

377

Dielectric Elastomers for Actuation and Energy Harvesting  

E-Print Network [OSTI]

The focus on high energy density materials ignores the factrelatively high energy density make this material suitableThe ideal DE material will have high energy density, low

Brochu, Paul

2012-01-01T23:59:59.000Z

378

Testing time-dependent density functional theory with depopulated molecular orbitals for predicting electronic excitation energies of valence, Rydberg, and charge-transfer  

E-Print Network [OSTI]

Testing time-dependent density functional theory with depopulated molecular orbitals for predicting functionals for time-dependent density functional theory calculations of valence and Rydberg electronic functional that performs well for both ground-state properties and time-dependent density functional theory

Truhlar, Donald G

379

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)

380

Electronic density-of-states of amorphous vanadium pentoxide films: Electrochemical data and density functional theory calculations  

SciTech Connect (OSTI)

Thin films of V{sub 2}O{sub 5} were prepared by sputter deposition onto transparent and electrically conducting substrates and were found to be X-ray amorphous. Their electrochemical density of states was determined by chronopotentiometry and displayed a pronounced low-energy peak followed by an almost featureless contribution at higher energies. These results were compared with density functional theory calculations for amorphous V{sub 2}O{sub 5}. Significant similarities were found between measured data and computations; specifically, the experimental low-energy peak corresponds to a split-off part of the conduction band apparent in the computations. Furthermore, the calculations approximately reproduce the experimental band gap observed in optical measurements.

Lykissa, Iliana; Li, Shu-Yi; Granqvist, Claes G.; Niklasson, Gunnar A., E-mail: gunnar.niklasson@angstrom.uu.se [Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, P.O. Box 534, SE-75121 Uppsala (Sweden); Ramzan, Muhammad [Department of Physics and Astronomy, The Ångström Laboratory, Uppsala University, P.O. Box 516, SE-75120 Uppsala (Sweden); Chakraborty, Sudip; Ahuja, Rajeev [Department of Physics and Astronomy, The Ångström Laboratory, Uppsala University, P.O. Box 516, SE-75120 Uppsala (Sweden); Applied Materials Physics, Department of Materials and Engineering, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden)

2014-05-14T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Science Taking Higher  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

4, 1997 4, 1997 Number 7 f Science Taking Higher Profile in Capital continued on page 8 INSIDE 2 Computers and Accelerators 4 Inventions 6 Sloan Digital Sky Survey upon the Clinton Administration and the 105th Congress to increase the nation's investment in scientific research and education. This awareness of science issues emanating from the nation's capital has heartened many of those toiling in the country's laboratories and universities; however, researchers interviewed for this article also said they are closely observing how the rhetoric translates into increased funding as the appropriations process plays out. "I see these [initiatives] as demonstrations of the underlying support of basic science in the community and in Congress," said Jeffrey Photo courtesy

382

BLACK HOLE ENTROPY IN HIGHER CURVATURE GRAVITY  

E-Print Network [OSTI]

We discuss some recent results on black hole thermodynamics within the context of effective gravitational actions including higher-curvature interactions. Wald's derivation of the First Law demonstrates that black hole entropy can always be expressed as a local geometric density integrated over a space-like cross-section of the horizon. In certain cases, it can also be shown that these entropy expressions satisfy a Second Law. One such simple example is considered from the class of higher curvature theories where the Lagrangian consists of a polynomial in the Ricci scalar.

TED JACOBSON; GUNGWON KANG; ROBERT C. MYERS

1995-02-27T23:59:59.000Z

383

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

384

Collisional Processes at Low Densities in Magnetic Mirror Systems  

Science Journals Connector (OSTI)

The study of collisional processes in plasmas produced by neutral?atom injection into magnetic mirror fields is described. The emphasis is on the many collisional processes which occur as the plasma density increases. Experimental and theoretical results are given. The experimental results are discussed first in terms of a simple model which assumes a Maxwellian electron distribution and a monoenergetic ion component of much higher energy. Analytical solutions may be obtained for this model. Also presented is a more complete theory employing two time?dependent Fokker?Planck equations to describe the behavior of the electron and ion distribution functions. Both models are in good agreement with measured values of the electron temperature and plasma potential. The equilibrium values of these two quantities are found to vary as the 3 5 power of the ratio of the plasma density to the background?gas density.

A. H. Futch; C. C. Damm; J. H. Foote; A. L. Gardner; J. Killeen

1971-01-01T23:59:59.000Z

385

The impact of residential density on vehicle usage and fuel consumption  

E-Print Network [OSTI]

residential density on vehicle usage and energy consumption.of residential density on vehicle usage and fuel consumptionresidential density on vehicle usage and fuel consumption*

Kim, Jinwon; Brownstone, David

2010-01-01T23:59:59.000Z

386

DENSITY FUNCTIONAL THEORY OF FIELD THEORETICAL SYSTEMS  

E-Print Network [OSTI]

DENSITY FUNCTIONAL THEORY OF FIELD THEORETICAL SYSTEMS E. Engel Inst. fur Theor. Physik background of relativistic density functional theory is emphasized and its consequences for relativistic Kohn-Sham equations are shown. The local density approximation for the exchange energy functional is reviewed

Engel, Eberhard

387

Generalized local-density approximation and one-dimensional finite uniform electron gases  

E-Print Network [OSTI]

We explicitly build a generalized local-density approximation (GLDA) correlation functional based on one-dimensional (1D) uniform electron gases (UEGs). The fundamental parameters of the GLDA \\textemdash a generalization of the widely-known local-density approximation (LDA) used in density-functional theory (DFT) \\textemdash are the electronic density $\\rho$ and a newly-defined two-electron local parameter called the hole curvature $\\eta$. The UEGs considered in this study are finite versions of the conventional infinite homogeneous electron gas and consist of $n$ electrons on a infinitely thin wire with periodic boundary conditions. We perform a comprehensive study of these finite UEGs at high, intermediate and low densities using perturbation theory and quantum Monte Carlo calculations. We show that the present GLDA functional yields accurate estimates of the correlation energy for both weakly and strongly correlated one-dimensional systems and can be easily generalized to higher-dimensional systems.

Loos, Pierre-François

2014-01-01T23:59:59.000Z

388

Spin-polarized energy-band structure, conduction-electron polarization, spin densities, and the neutron magnetic form factor of ferromagnetic gadolinium  

Science Journals Connector (OSTI)

Conduction-electron polarization, spin densities, and neutron magnetic scattering in ferromagnetic Gd metal were studied using the spin-polarized augmented-plane-wave (APW) method in a warped-muffin-tin-potential formulation. The spin-up and spin-down bands were found to be very similar in shape to the bands from a paramagnetic calculation, with the exchange splitting proportional to the amount of d character in the bands. It was also found that the conduction-electron spin density determined from the APW wave functions is of mostly d character. This dominance of the d-like wave functions for the spin-dependent interactions is explained by (i) the much greater overlap of the 4f states with the d-like wave functions as compared to the s-p wave functions; (ii) the nearly complete d character of the bands in the region of the Fermi surface. The magnetic form factor was calculated from the conduction-electron spin density and compared with the recent neutron magnetic - form - factor measurement of Moon, Koehler, Cable, and Child. The calculated spin density was found to have the same shape as the "diffuse" density derived by Moon et al. (including a negative but much smaller in magnitude spin density at the c site in the unit cell). After the inclusion of core - polarization effects we conclude that large nonspherical contributions with Y33-Y3-3, and Y40 angular dependence are needed to explain the experimental results.

B. N. Harmon and A. J. Freeman

1974-09-01T23:59:59.000Z

389

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect (OSTI)

High-density micron-sized particle aerosols might form the basis for a number of applications in which a material target with a particular shape might be quickly ionized to form a cylindrical or sheet shaped plasma. A simple experimental device was built in order to study the properties of high-density aerosol focusing for 1#22; m silica spheres. Preliminary results recover previous findings on aerodynamic focusing at low densities. At higher densities, it is demonstrated that the focusing properties change in a way which is consistent with a density dependent Stokes number.

Ruiz, D. E.; Fisch, Nathaniel

2014-02-24T23:59:59.000Z

390

Energy content: 43 to 47 KJ/gram not much different from candlewax or candybars (physical density of gasoline is about .73 times that of water (.73 g/cc...it floats!).  

E-Print Network [OSTI]

GASOLINE: Energy content: 43 to 47 KJ/gram not much different from candlewax or candybars (physical density of gasoline is about .73 times that of water (.73 g/cc...it floats!). Coal...15 to 19 KJ/gram H H-C-C-C-C-C-C-C-C-H Decane | | | | | | | | | | H H H H H H H H H H Typical molecules found in gasoline Rough Values of Power

391

Quantum critical benchmark for density functional theory  

E-Print Network [OSTI]

Two electrons at the threshold of ionization represent a severe test case for electronic structure theory. A pseudospectral method yields a very accurate density of the two-electron ion with nuclear charge close to the critical value. Highly accurate energy components and potentials of Kohn-Sham density functional theory are given, as well as a useful parametrization of the critical density. The challenges for density functional approximations and the strength of correlation are also discussed.

Paul E. Grabowski; Kieron Burke

2014-08-09T23:59:59.000Z

392

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.

Farkas, Zénó

2011-01-01T23:59:59.000Z

393

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

394

Dark Matter Density in Disk Galaxies  

E-Print Network [OSTI]

I show that the predicted densities of the inner dark matter halos in LCDM models of structure formation appear to be higher than estimates from real galaxies and constraints from dynamical friction on bars. This inconsistency would not be a problem for the LCDM model if physical processes that are omitted in the collisionless collapse simulations were able to reduce the dark matter density in the inner halos. I review the mechanisms proposed to achieve the needed density reduction.

J. A. Sellwood

2008-07-12T23:59:59.000Z

395

Horizon entropy and higher curvature equations of state  

E-Print Network [OSTI]

The Clausius relation between entropy change and heat flux has previously been used to derive Einstein's field equations as an equation of state. In that derivation the entropy is proportional to the area of a local causal horizon, and the heat is the energy flux across the horizon, defined relative to an approximate boost Killing vector. We examine here whether a similar derivation can be given for extensions beyond Einstein gravity to include higher derivative and higher curvature terms. We review previous proposals which, in our opinion, are problematic or incomplete. Refining one of these, we assume that the horizon entropy depends on an approximate local Killing vector in a way that mimics the diffeomorphism Noether charge that yields the entropy of a stationary black hole. We show how this can be made to work if various restrictions are imposed on the nature of the horizon slices and the approximate Killing vector. Also, an integrability condition on the assumed horizon entropy density must hold. This can yield field equations of a Lagrangian constructed algebraically from the metric and Riemann tensor, but appears unlikely to allow for derivatives of curvature in the Lagrangian.

Raf Guedens; Ted Jacobson; Sudipta Sarkar

2012-01-02T23:59:59.000Z

396

High-Rate and High-Energy-Density Lithium-Ion Battery Anode Containing 2D MoS2 Nanowall and Cellulose Binder  

Science Journals Connector (OSTI)

We thank “National Centre for Photovolatic Research and Education (NCPRE)”-Ministry of New and Renewable Energy, Government of India and IRCC-IIT Bombay for their support. ...

Uttam Kumar Sen; Sagar Mitra

2013-01-28T23:59:59.000Z

397

GreenCharge: Managing Renewable Energy in Smart Buildings  

E-Print Network [OSTI]

of future energy demand/harvesting and a system that only leverages a battery to lower costs (without any foot, is higher than the energy generation density of solar and wind deployments at most locations centralized power plants benefit from economies-of-scale that cause their generation costs, even accounting

Shenoy, Prashant

398

GreenCharge: Managing Renewable Energy in Smart Buildings  

E-Print Network [OSTI]

foot, is higher than the energy generation density of solar and wind deployments at most locations centralized power plants benefit from economies-of-scale that cause their generation costs, even accounting--to offset their cost relative to grid energy. DG is a much less financially attractive where net metering

Kurose, Jim

399

Laboratory Density Functionals  

E-Print Network [OSTI]

We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

B. G. Giraud

2007-07-26T23:59:59.000Z

400

Highly Robust Thin-Film Composite Pressure Retarded Osmosis (PRO) Hollow Fiber Membranes with High Power Densities for Renewable Salinity-Gradient Energy Generation  

Science Journals Connector (OSTI)

(1) Salinity-gradient energy (i.e., osmotic power) generated from the mixing of solutions with different salinities via pressure retarded osmosis (PRO) represents a high potential source of renewable energy. ... Thorsen, T.; Holt, T.The potential for power production from salinity gradients by pressure retarded osmosis J. Membr. ... When using saline water as the feed soln., the efficiency of the osmotic pressure decreases with increasing feed concn. ...

Gang Han; Peng Wang; Tai-Shung Chung

2013-06-17T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

This open letter was inspired by a competition between college and university students attending member schools of the Association for the Advancement of Sustainability in Higher Education (AASHE). The competition, dubbed TEAMS for Tomorrow's Energy Ambas  

E-Print Network [OSTI]

into the electricity grid and make low-carbon power plants the status quo. Renewable energy sources, such as wind as the next president has the potential to substantially impact future generations. However, energy). The competition, dubbed TEAMS for Tomorrow's Energy Ambassadors, Managers and Scholars, invited students at more

Attari, Shahzeen Z.

402

The Swedish Higher Education System  

E-Print Network [OSTI]

EDUCATION Higher education within all cycles has two strata of entry requirements: general and (additional) specific requirements. General eligibility to the first cycle is the same for all higher education. General and courses. DEGREE-AWARDING POWERS Universities have the general right to award first-, second- and third-cycle

Zhao, Yuxiao

403

Cast Stone Formulation At Higher Sodium Concentrations  

SciTech Connect (OSTI)

A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leachability indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the l

Fox, K. M.; Roberts, K. A.; Edwards, T. B.

2014-02-28T23:59:59.000Z

404

Energy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Energy newsroomassetsimagesenergy-icon.png Energy Research into alternative forms of energy, and improving and securing the power grid, is a major national security...

405

Competitions for Higher Education Students  

Broader source: Energy.gov [DOE]

Here you'll find student resources on competitions that promote awareness about energy technologies and issues.

406

Symmetric Density Functionals  

E-Print Network [OSTI]

Variations in distinct restricted spaces of wave functions generate distinct density functionals. In particular, angular momentum projected Slater determinants define a new density functional, compatible simultaneously with angular momentum quantum number and mean field descriptions.

B. G. Giraud

2005-07-13T23:59:59.000Z

407

Density measurements Viscosity measurements  

E-Print Network [OSTI]

Density measurements Viscosity measurements Temperature measurements Pressure measurements Flow rate measurements Velocity measurements Sensors How to measure fluid flow properties ? Am´elie Danlos Ravelet Experimental methods for fluid flows: an introduction #12;Density measurements Viscosity

Ravelet, Florent

408

Ions in solution: Density corrected density functional theory (DC-DFT)  

SciTech Connect (OSTI)

Standard density functional approximations often give questionable results for odd-electron radical complexes, with the error typically attributed to self-interaction. In density corrected density functional theory (DC-DFT), certain classes of density functional theory calculations are significantly improved by using densities more accurate than the self-consistent densities. We discuss how to identify such cases, and how DC-DFT applies more generally. To illustrate, we calculate potential energy surfaces of HO·Cl{sup ?} and HO·H{sub 2}O complexes using various common approximate functionals, with and without this density correction. Commonly used approximations yield wrongly shaped surfaces and/or incorrect minima when calculated self consistently, while yielding almost identical shapes and minima when density corrected. This improvement is retained even in the presence of implicit solvent.

Kim, Min-Cheol; Sim, Eunji, E-mail: esim@yonsei.ac.kr [Department of Chemistry and Institute of Nano-Bio Molecular Assemblies, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul 120-749 (Korea, Republic of)] [Department of Chemistry and Institute of Nano-Bio Molecular Assemblies, Yonsei University, 50 Yonsei-ro Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Burke, Kieron [Department of Chemistry, University of California, Irvine, California 92697 (United States)] [Department of Chemistry, University of California, Irvine, California 92697 (United States)

2014-05-14T23:59:59.000Z

409

Higher Yields Can Be Achieved  

Gasoline and Diesel Fuel Update (EIA)

8 8 Notes: While the current forecast is showing higher distillate production than last year, there is room for yet more volume through refiners switching to higher yields than those being forecast. This will only happen if economic incentives evolve to encourage this change. Current high spreads indicate those incentives may occur. This graph shows the distillate yield pattern over the last few years. Generally yields rise in the fall to build stocks for winter distillate use. On average, the yield increase during the fourth quarter is about 2% higher than the yield average of the lowest yield months of June, July and August. (Recognize that a 1% change in yield is about a 150 MB/D change in distillate production, which is about 4% of winter demand.) During the fall of 1996, the winter season began with very low

410

Complex higher order derivative theories  

SciTech Connect (OSTI)

In this work is considered a complex scalar field theory with higher order derivative terms and interactions. A procedure is developed to quantize consistently this system avoiding the presence of negative norm states. In order to achieve this goal the original real scalar high order field theory is extended to a complex space attaching a complex total derivative to the theory. Next, by imposing reality conditions the complex theory is mapped to a pair of interacting real scalar field theories without the presence of higher derivative terms.

Margalli, Carlos A.; Vergara, J. David [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico 04510 DF (Mexico)

2012-08-24T23:59:59.000Z

411

Spin density matrix elements in exclusive $?$ electroproduction on $^1$H and $^2$H targets at 27.5 GeV beam energy  

E-Print Network [OSTI]

Exclusive electroproduction of $\\omega$ mesons on unpolarized hydrogen and deuterium targets is studied in the kinematic region of Q$^2$>1.0 GeV$^2$, 3.0 GeV products, are presented. The data were accumulated with the HERMES forward spectrometer during the 1996-2007 running period using the 27.6 GeV longitudinally polarized electron or positron beam of HERA. The determination of the virtual-photon longitudinal-to-transverse cross-section ratio reveals that a considerable part of the cross section arises from transversely polarized photons. Spin density matrix elements are presented in projections of Q$^2$ or -t'. Violation of s-channel helicity conservation is observed for some of these elements. A sizable contribution from unnatural-parity-exchange amplitudes is found and the phase shift between those amplitudes that describe transverse $\\omega$ production by longitudinal and transverse virtual photons, $\\gamma^{*}_{L} \\to \\omega_{T}$ and $\\gamma^{*}_{T} \\to \\omega_{T}$, is determined for the first time. A hierarchy of helicity amplitudes is established, which mainly means that the unnatural-parity-exchange amplitude describing the $\\gamma^*_T \\to \\omega_T$ transition dominates over the two natural-parity-exchange amplitudes describing the $\\gamma^*_L \\to \\omega_L$ and $\\gamma^*_T \\to \\omega_T$ transitions, with the latter two being of similar magnitude. Good agreement is found between the HERMES proton data and results of a pQCD-inspired phenomenological model that includes pion-pole contributions, which are of unnatural parity.

The HERMES Collaboration; A. Airapetian; N. Akopov; Z. Akopov; W. Augustyniak; A. Avetissian; H. P. Blok; A. Borissov; V. Bryzgalov; M. Capiluppi; G. P. Capitani; E. Cisbani; G. Ciullo; M. Contalbrigo; P. F. Dalpiaz; W. Deconinck; R. De Leo; E. De Sanctis; M. Diefenthaler; P. Di Nezza; M. Düren; M. Ehrenfried; G. Elbakian; F. Ellinghaus; E. Etzelmüller; R. Fabbri; L. Felawka; S. Frullani; D. Gabbert; G. Gapienko; V. Gapienko; F. Garibaldi; G. Gavrilov; V. Gharibyan; M. Hartig; D. Hasch; Y. Holler; I. Hristova; A. Ivanilov; H. E. Jackson; S. Joosten; R. Kaiser; G. Karyan; T. Keri; E. Kinney; A. Kisselev; V. Korotkov; V. Kozlov; P. Kravchenko; V. G. Krivokhijine; L. Lagamba; L. Lapikás; I. Lehmann; P. Lenisa; W. Lorenzon; B. -Q. Ma; D. Mahon; S. I. Manaenkov; Y. Mao; B. Marianski; H. Marukyan; A. Movsisyan; M. Murray; Y. Naryshkin; A. Nass; W. -D. Nowak; L. L. Pappalardo; R. Perez-Benito; A. Petrosyan; P. E. Reimer; A. R. Reolon; C. Riedl; K. Rith; A. Rostomyan; D. Ryckbosch; A. Schäfer; G. Schnell; K. P. Schüler; B. Seitz; T. -A. Shibata; M. Stahl; M. Stancari; M. Statera; E. Steffens; J. J. M. Steijger; S. Taroian; A. Terkulov; R. Truty; A. Trzcinski; M. Tytgat; Y. Van Haarlem; C. Van Hulse; V. Vikhrov; I. Vilardi; S. Wang; S. Yaschenko; S. Yen; D. Zeiler; B. Zihlmann; P. Zupranski

2014-07-08T23:59:59.000Z

412

Lower Cost, Higher Performance Carbon Fiber  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

David (Dave) Warren David (Dave) Warren Field Technical Manager Transportation Materials Research Oak Ridge National Laboratory P.O. Box 2009, M/S 8050 Oak Ridge, Tennessee 37831-8050 Phone: 865-574-9693 Fax: 865-574-0740 Email: WarrenCD@ORNL.GOV Lower Cost, Higher Performance Carbon Fiber 14 February 2011 2 Managed by UT-Battelle for the U.S. Department of Energy Presentation_name Questions for Today Materials How can the cost of carbon fiber suitable for higher performance applications (H 2 Storage) be developed? H 2 Storage requirements implies Aerospace grade fibers. Can we build off of work previously done for more modest structural applications? To accurately answer: We need to know the minimum performance and maximum cost requirements of the fiber not simply the properties of current fiber.

413

Lorentz violation and higher-derivative gravity  

E-Print Network [OSTI]

In this work, we analyze a gravity model with higher derivatives including a CPT-even Lorentz-violating term. In principle, the model could be a low-energy limit of a Lorentz-invariant theory presenting the violation of Lorentz symmetry as a consequence of a spontaneous symmetry-breaking mechanism if a decoupling between the metric and the Nambu-Goldstone modes is assumed. We have set up a convenient operator basis for the expansion of wave operators for symmetric second-rank tensors in the presence of a background vector. By using this set of operators, the particle content is obtained, and its consistency, regarding the conditions for stability and unitarity, is discussed. We conclude that this extra Lorentz noninvariant contribution is unable to address the problems of stability and unitarity of higher-derivative gravity models.

Hernaski, C

2014-01-01T23:59:59.000Z

414

Tax Benefits and Higher Education  

E-Print Network [OSTI]

payments Tax Benefits and Higher Education Lifetime Learning Credit A nonrefundable tax credit of up to $2 deductions,tax credits are subtracted from the amount of tax owed,rather than your taxable income tax credit allows you to reduce the amount of your tax by up to $1,500 (subject to certain phaseouts

Gelfond, Michael

415

Neutral depletion and the helicon density limit  

SciTech Connect (OSTI)

It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup ?3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 ?s. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States)

2013-12-15T23:59:59.000Z

416

Contained Energy Inc | Open Energy Information  

Open Energy Info (EERE)

Energy Inc Place: Shaker Heights, Ohio Zip: 44120 Sector: Carbon Product: Develops, manufactures, markets and sells direct carbon fuel cells with breakthrough energy density....

417

Energy Dependence of the Single-Particle Self-Energy Correction for Ge and Si  

Science Journals Connector (OSTI)

The energy dependence of the self-energy correction ?(E) to local-density-functional pseudopotential theory has been determined for Si and Ge from -15 to 16 eV above the Fermi energy EF, and compared to recent calculations. The real part of ?(E) was determined from the shift, relative to calculations, of detailed x-ray bremsstrahlung isochromat spectra, which exhibited many new higher-energy features, and x-ray photoemission spectra; the imaginary part was estimated from escape-depth data and the widths of conduction-band features. The real part changes abruptly at EF and is otherwise roughly constant, even up to the plasmon energy.

W. B. Jackson, John E. Northrup, J. W. Allen, and R. I. Johnson

1986-03-17T23:59:59.000Z

418

Wave energy  

Science Journals Connector (OSTI)

Waves receive their energy from the wind by means of a ... whose yield is not yet clearly understood. Energy in the wave is more concentrated than in the wind ... density. For this reason a motor utilizing wave p...

Ferruccio Mosetti

1982-01-01T23:59:59.000Z

419

Energy  

Science Journals Connector (OSTI)

Energy ... “Scientific Challenges in Sustainable Energy Technology,” by Nathan S. Lewis of the California Institute of Technology, summarizes data on energy resources and analyses the implications for human society. ... ConfChem Conference on Educating the Next Generation: Green and Sustainable Chemistry—Solar Energy: A Chemistry Course on Sustainability for General Science Education and Quantitative Reasoning ...

John W. Moore

2008-07-01T23:59:59.000Z

420

The energy production rate density of cosmic rays in the local universe is $\\sim10^{44-45}\\rm erg~Mpc^{-3}~yr^{-1}$ at all particle energies  

E-Print Network [OSTI]

The energy output (per logarithmic interval of particle energies) of Cosmic Rays (CRs) with energies $10{\\rm GeV}\\lesssim\\varepsilon_p\\lesssim100{\\rm GeV}$ is $\\sim 10^{47}\\rm erg$ per solar mass of star$-$formation, based on the CR production rate in the Milky Way and in starburst galaxies, implying a generation rate of $\\varepsilon_p^2Q\\sim 10^{45}\\rm erg~Mpc^{-3}~yr^{-1}$ in the local universe. It is only $\\sim 10$ times larger than the output, $\\varepsilon_p^2 Q=0.5\\pm0.2\\times 10^{44}\\rm erg~Mpc^{-3}~yr^{-1}$, of Ultra High Energy CRs (UHECRs) at energies $10^{10.5}{\\rm GeV}<\\varepsilon_p<10^{12}\\rm GeV$ (obtained assuming they are mostly protons), which in turn is comparable to the lower limit of $\\varepsilon_p^2 Q\\ge 0.5\\times 10^{44}\\rm erg~Mpc^{-3}~yr^{-1}$ of high energy CRs with $10^6{\\rm GeV}\\lesssim\\varepsilon_p\\lesssim 10^{8}\\rm GeV$ implied by the saturation of the Waxman-Bahcall bound by the neutrino excess recently discovered by IceCube. These similarities are consistent with a flat pro...

Katz, Boaz; Thompson, Todd; Loeb, Abraham

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Electronic density of states of amorphous Si and Ge: Application of a molecular-liquid model  

Science Journals Connector (OSTI)

The electronic structures of a-Si and a-Ge have been investigated by introducing the molecular-liquid model (MLM). The theoretical structure factors have been expressed in terms of three simple parameters—nearest-neighbor distance, packing density, and coordination number. For the electronic density of states (EDS), nonlocal energy-dependent pseudopotentials have been considered to second order in perturbation theory. When compared with the experimental structure factors, the MLM structure factors agree well for the momentum transfer in the region of 0higher values of k. The calculated energy values exhibit a number of new features in the E2 vs k curves that were not noticed previously with local-pseudopotential and on-Fermi-surface approximation. The EDS, however, show remarkably good agreement with recent theoretical and experimental results.

N. C. Halder

1980-01-15T23:59:59.000Z

422

Webcast of the 'Energy 101' Course Framework  

Broader source: Energy.gov [DOE]

Energy 101: A Model Interdisciplinary Higher Education Course for Teaching the Fundamentals of Energy

423

Recycling of wasted energy : thermal to electrical energy conversion  

E-Print Network [OSTI]

density, making direct thermal energy storage methods, e.g.reduced. Conventional thermal energy harvesting and storageharvesting, storage, and utilization of thermal energy has

Lim, Hyuck

2011-01-01T23:59:59.000Z

424

California’s Energy Future: Transportation Energy Use in California  

E-Print Network [OSTI]

commodity and energy prices, and alternative advancedany alternative fuel system, gravimetric energy density (MJ/and hydrogen as alternative fuels is in energy storage. The

Yang, Christopher

2011-01-01T23:59:59.000Z

425

DOE Proposes Higher Efficiency Standards for Refrigerators | Department of  

Broader source: Energy.gov (indexed) [DOE]

DOE Proposes Higher Efficiency Standards for Refrigerators DOE Proposes Higher Efficiency Standards for Refrigerators DOE Proposes Higher Efficiency Standards for Refrigerators September 28, 2010 - 12:00am Addthis WASHINGTON, DC - U.S. Energy Secretary Steven Chu today announced the release of a new proposed energy efficiency standard for residential refrigerators, refrigerator-freezers, and freezers. The standard, as proposed, could save consumers as much as $18.6 billion over thirty years. The Obama Administration has made efficiency standards a major priority as a way to save energy and money for American families and businesses. Since January 2009, the Department of Energy has finalized new efficiency standards for more than twenty household and commercial products, which will cumulatively save consumers between $250 billion and

426

How to Calculate Molecular Column Density  

E-Print Network [OSTI]

The calculation of the molecular column density from molecular spectral (rotational or ro-vibrational) transition measurements is one of the most basic quantities derived from molecular spectroscopy. Starting from first principles where we describe the basic physics behind the radiative and collisional excitation of molecules and the radiative transfer of their emission, we derive a general expression for the molecular column density. As the calculation of the molecular column density involves a knowledge of the molecular energy level degeneracies, rotational partition functions, dipole moment matrix elements, and line strengths, we include generalized derivations of these molecule-specific quantities. Given that approximations to the column density equation are often useful, we explore the optically thin, optically thick, and low-frequency limits to our derived general molecular column density relation. We also evaluate the limitations of the common assumption that the molecular excitation temperature is con...

Mangum, Jeffrey G

2015-01-01T23:59:59.000Z

427

Bone Mineral Density in Women with Depression  

Science Journals Connector (OSTI)

...illness and the normal women were individually matched for age, body-mass index, and menstrual status; women with many of the risk factors associated with decreased bone mineral density were excluded; dual-energy x-ray absorptiometry was used to measure bone density at the spine, hip, and radius; and bone... Major depression is a complex disorder reflecting genetic, developmental, and environmental factors. Although its pathophysiology is not clearly understood, depression is associated with hypothalamic dysfunction — specifically, hypercortisolism, the ...

Michelson D.; Stratakis C.; Hill L.

1996-10-17T23:59:59.000Z

428

Glossary | Department of Energy  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

polishes. Gravimetric Energy Density Potential energy in a given weight of fuel. Greenhouse Effect Warming of the Earth's atmosphere due to gases in the atmosphere that allow...

429

Heavy ion physics challenges at Bevalac/SIS energies  

SciTech Connect (OSTI)

This paper discusses where the future of higher energy heavy ion acceleration may lead in terms of understanding the nucleus. The discussion concerns obstacles to formulating an equation of state for nuclear matter at high temperature and density. Implications of this research for astrophysical problems is also presented. (LSP)

Gyulassy, M.

1987-11-01T23:59:59.000Z

430

Inner magnetosphere plasma densities  

E-Print Network [OSTI]

The radio plasma imager (RPI) on the IMAGE satellite performs radio sounding in the magnetosphere, transmitting coded signals stepping through the frequency range of interest and receiving the returned echoes. The measurements provide the echo amplitude as a function of frequency and echo delay time on a so-called plasmagram. A newly developed algorithm inverts THE echo traces on a plasmagram to electron density spatial distributions. Based on these observed density distributions, an empirical model is constructed to describe the two-dimensional density distribution in the inner magnetosphere.

Reinisch, B W

2002-01-01T23:59:59.000Z

431

Evolution of density perturbations in decaying vacuum cosmology  

SciTech Connect (OSTI)

We study cosmological perturbations in the context of an interacting dark energy model, in which the cosmological term decays linearly with the Hubble parameter, with concomitant matter production. A previous joint analysis of the redshift-distance relation for type Ia supernovas, barionic acoustic oscillations, and the position of the first peak in the anisotropy spectrum of the cosmic microwave background has led to acceptable values for the cosmological parameters. Here we present our analysis of small perturbations, under the assumption that the cosmological term, and therefore the matter production, are strictly homogeneous. Such a homogeneous production tends to dilute the matter contrast, leading to a late-time suppression in the power spectrum. Nevertheless, an excellent agreement with the observational data can be achieved by using a higher matter density as compared to the concordance value previously obtained. This may indicate that our hypothesis of homogeneous matter production must be relaxed by allowing perturbations in the interacting cosmological term.

Borges, H. A.; Pigozzo, C. [Instituto de Fisica, Universidade Federal da Bahia, Salvador, BA (Brazil); Carneiro, S. [Instituto de Fisica, Universidade Federal da Bahia, Salvador, BA (Brazil); International Centre for Theoretical Physics, Trieste (Italy); Fabris, J. C. [Institut d'Astrophysique de Paris, Paris (France)

2008-02-15T23:59:59.000Z

432

Higher order Hamiltonian fluid reduction of Vlasov , C. Chandre1  

E-Print Network [OSTI]

, France 2 Institute for Fusion Studies and Department of Physics, The University of Texas at Austin, the momentum density and the specific internal energy. We derive the Poisson bracket of this model from, and thus provide a Poisson bracket derivation of the more complete Hamiltonian theory of Ref. [11

433

Nuclear symmetry energy effects on liquid-gas phase transition in hot asymmetric nuclear matter  

E-Print Network [OSTI]

The liquid-gas phase transition in hot asymmetric nuclear matter is investigated within relativistic mean-field model using the density dependence of nuclear symmetry energy constrained from the measured neutron skin thickness of finite nuclei. We find symmetry energy has a significant influence on several features of liquid-gas phase transition. The boundary and area of the liquid-gas coexistence region, the maximal isospin asymmetry and the critical values of pressure and isospin asymmetry all of which systematically increase with increasing softness in the density dependence of symmetry energy. The critical temperature below which the liquid-gas mixed phase exists is found higher for a softer symmetry energy.

Bharat K. Sharma; Subrata Pal

2010-01-14T23:59:59.000Z

434

Density scaling and anisotropy in supersonic MHD turbulence  

E-Print Network [OSTI]

We study the statistics of density for supersonic turbulence in a medium with magnetic pressure larger than the gaseous pressure. This study is motivated by molecular cloud research. Our simulations exhibit clumpy density structures, which contrast increases with the Mach number. At 10 Machs densities of some clumps are three orders of magnitude higher than the mean density. These clumps give rise to flat and approximately isotropic density spectrum corresponding to the random distribution of clumps in space. We claim that the clumps originate from our random, isotropic turbulence driving. When the contribution from those clumps is suppressed by studying logarithm of density, the density statistics exhibit scale-dependent anisotropy consistent with the models where density structures arise from shearing by Alfv\\'en waves. It is noteworthy that originally such models were advocated for the case of low-Mach, nearly incompressible turbulence.

A. Beresnyak; A. Lazarian; J. Cho

2005-02-25T23:59:59.000Z

435

Achieving Higher Performance with Cost Neutrality through Building America  

Broader source: Energy.gov (indexed) [DOE]

Achieving Higher Performance Achieving Higher Performance with Cost Neutrality through Building America Residential Energy Efficiency Stakeholder Meeting March 1, 2012 Residential Energy Efficiency Stakeholder Meeting Agenda * Imagine Homes - An Overview * 2010 Occupied Test House - Objectives - From Modeling through Monitoring * 2012 Occupied Test House - Objectives - What's Next * Closing Remarks Residential Energy Efficiency Stakeholder Meeting Overview: * San Antonio, TX * 68 Homes in 2011 * $140k - $425k * 1,300 - 4,500 ft 2 Imagine Homes Residential Energy Efficiency Stakeholder Meeting Environment: * Hot-Humid * 2,996 CDD * 1,546 HDD * 31" Rainfall Imagine Homes Residential Energy Efficiency Stakeholder Meeting Imagine Homes History: * Established 2006 * Partnership with Beazer Homes * Builders Challenge * Building America

436

Pseudorapidity Density of Charged Particles in p+Pb Collisions at sNN=5.02??TeV  

Science Journals Connector (OSTI)

The charged-particle pseudorapidity density measured over four units of pseudorapidity in nonsingle-diffractive p+Pb collisions at a center-of-mass energy per nucleon pair sNN=5.02??TeV is presented. The average value at midrapidity is measured to be 16.81±0.71??(syst), which corresponds to 2.14±0.17??(syst) per participating nucleon, calculated with the Glauber model. This is 16% lower than in nonsingle-diffractive pp collisions interpolated to the same collision energy and 84% higher than in d+Au collisions at sNN=0.2??TeV. The measured pseudorapidity density in p+Pb collisions is compared to model predictions and provides new constraints on the description of particle production in high-energy nuclear collisions.

B. Abelev et al. (ALICE Collaboration)

2013-01-18T23:59:59.000Z

437

Generalized Holographic Superconductors with Higher Derivative Couplings  

E-Print Network [OSTI]

We introduce and study generalized holographic superconductors with higher derivative couplings between the field strength tensor and a complex scalar field, in four dimensional AdS black hole backgrounds. We study this theory in the probe limit, as well as with backreaction. There are multiple tuning parameters in the theory, and with two non-zero parameters, we show that the theory has a rich phase structure, and in particular, the transition from the normal to the superconducting phase can be tuned to be of first order or of second order within a window of one of these. This is established numerically as well as by computing the free energy of the boundary theory. We further present analytical results for the critical temperature of the model, and compare these with numerical analysis. Optical properties of this system are also studied numerically in the probe limit, and our results show evidence for negative refraction at low frequencies.

Anshuman Dey; Subhash Mahapatra; Tapobrata Sarkar

2014-06-13T23:59:59.000Z

438

Search for High Energy Density Cathode Materials  

Broader source: Energy.gov [DOE]

2010 DOE Vehicle Technologies and Hydrogen Programs Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C.

439

High energy density redox flow device  

DOE Patents [OSTI]

Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

Chiang, Yet-Ming; Carter, William Craig; Duduta, Mihai; Limthongkul, Pimpa

2014-05-13T23:59:59.000Z

440

Aerodynamic focusing of high-density aerosols D.E. Ruiz a,n  

E-Print Network [OSTI]

Aerodynamic focusing of high-density aerosols D.E. Ruiz a,n , L.M. Gunderson a , M.J. Hay a , E Accepted 24 May 2014 Available online 17 June 2014 Keywords: Aerodynamic lens High-density aerosol beam recover previous findings on aerodynamic focusing at low densities. At higher densities

Note: This page contains sample records for the topic "higher energy 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.


441

Energy  

Gasoline and Diesel Fuel Update (EIA)

Federal, State, local, and foreign governments, EIA survey respondents, and the media. For further information, and for answers to questions on energy statistics, please...

442

Energy  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Energy Energy Energy Express Licensing Accelerator-Driven Transmutation Of Spent Fuel Elements Express Licensing Acid-catalyzed dehydrogenation of amine-boranes Express Licensing Air Breathing Direct Methanol Fuel Cell Express Licensing Aligned Crystalline Semiconducting Film On A Glass Substrate And Method Of Making Express Licensing Anion-Conducting Polymer, Composition, And Membrane Express Licensing Apparatus for Producing Voltage and Current Pulses Express Licensing Biaxially oriented film on flexible polymeric substrate Express Licensing Corrosion Test Cell For Bipolar Plates Express Licensing Device for hydrogen separation and method Negotiable Licensing Durable Fuel Cell Membrane Electrode Assembly (MEA) Express Licensing Energy Efficient Synthesis Of Boranes Express Licensing

443

THE UNIVERSITY OF SHEFFIELD CATALYST HIGHER EDUCATION  

E-Print Network [OSTI]

Page | 1 THE UNIVERSITY OF SHEFFIELD & CATALYST HIGHER EDUCATION (SHEFFIELD) PLC. UNIVERSITY of Sheffield / Catalyst Higher Education (Sheffield) plc Project Co Accommodation: Accommodation / Catalyst Higher Education (Sheffield) plc LLFM: Lend Lease Facilities Management Ltd Project Co: Catalyst

Dixon, Peter

444

Buoyancy-generated variable-density turbulence  

SciTech Connect (OSTI)

Because of the importance of turbulence mixing in many applications, a number of turbulence mixing models have been proposed for variable- density flows. These engineering models (one- point statistical models) typically include the transport of the turbulent kinetic energy and the turbulent energy dissipation rate (i.e., k - {epsilon} models). The model presented by Besnard, Harlow, Rauenzahn and Zemach (1992) (herein referred to as BHRZ) is a one-point model intended to describe variable-density turbulent flows. Transport equations for the Reynolds stress tensor, R{sub ij}, and the turbulent energy dissipation rate, the density-velocity correlation, a{sub i}, and the density-specific volume correlation, b are derived. This model employs- techniques and concepts from incompressible, constant- density turbulence modeling and incorporates ideas from two-phase flow models. Clark and Spitz (1994) present a two-point model for variable-density turbulence. Their derivation is based on transport equations that, are based 0481 on two-point- generalizations of R{sub ij}, a{sub ij}, and b. These equations are Fourier transformed with respect to the separation distance between the two points. Transport equations are derived for R{sub ij}, a{sub i}, b. As in the one-point model, this model contains many ad-hoc assumptions and unknown model coefficients that must be determined by comparison with experimental and numerical data. However, the two-point formalism requires fewer equilibrium assumptions then does a single-point model. Our primary concern in this paper lies in the nonlinear processes of turbulence and the influence of large density variations (not within the Boussinesq limit) on these processes. To. isolate the effects of variable-density on the turbulence we restrict our flow to be incompressible, statistically homogeneous buoyancy-generated. turbulence. To our knowledge there have not been any simulations reported for this problem.

Sandoval, D.L.; Clark, T.T.; Riley, J.J.

1996-07-01T23:59:59.000Z

445

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

446

Nuclear symmetry energy  

Science Journals Connector (OSTI)

To study the nuclear symmetry energy, we extend the Dirac-Brueckner approach with a Bonn one-boson-exchange nucleon-nucleon interaction to the general case of asymmetric nuclear matter. We extract the symmetry energy coefficient at the saturation to be about 31 MeV, which is in good agreement with the empirical value of 30±4 MeV. The symmetry energy is found to increase almost linearly with the density, which differs considerably from the results of nonrelativistic approaches. This finding also supports the linear parametrization of Prakash, Ainsworth, and Lattimer. We find, furthermore, that the higher-order dependence of the nuclear equation of state on the asymmetry parameter is unimportant.

C.-H. Lee; T. T. S. Kuo; G. Q. Li; G. E. Brown

1998-06-01T23:59:59.000Z

447

U.S. Wind Manufacturing: Taller Hub Heights to Access Higher...  

Broader source: Energy.gov (indexed) [DOE]

U.S. Wind Manufacturing: Taller Hub Heights to Access Higher Wind Resources and Lower Cost of Energy U.S. Wind Manufacturing: Taller Hub Heights to Access Higher Wind Resources and...

448

Single-Nucleon Densities  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (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);

449

Carbon-based Materials for Energy Storage  

E-Print Network [OSTI]

2 O 5 ) nanowires, a high-energy material with a capacity ofhigh power density and low energy density of traditional dielectric capacitor materialsenergy density in capacitor materials while retaining high

Rice, Lynn Margaret

2012-01-01T23:59:59.000Z

450

Density Functional Theory for Superconductors  

E-Print Network [OSTI]

Density Functional Theory for Superconductors LATHIOTAKIS, A. MARQUES, 1,2,3 LU DERS, L. FAST, 2004 words: theory superconductors; density functional theory; critical temperature; exchange matter physics theoretical chemistry is density functional theory (DFT). foundations were established mid

Gross, E.K.U.

451

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

452

A long-range-corrected density functional that performs well for both ground-state properties and time-dependent density functional theory  

E-Print Network [OSTI]

and time-dependent density functional theory excitation energies, including charge-transfer excited states energies within time-dependent density functional theory, is systematically evaluated, and optimal values. THEORETICAL BACKGROUND Generalized gradient approximations GGAs in density functional theory DFT are quite

Herbert, John

453

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

2013-01-20T23:59:59.000Z

454

Density Perturbations for Running Cosmological Constant  

E-Print Network [OSTI]

The dynamics of density and metric perturbations is investigated for the previously developed model where the decay of the vacuum energy into matter (or vice versa) is due to the renormalization group (RG) running of the cosmological constant (CC) term. The evolution of the CC depends on the single parameter \

Julio C. Fabris; Ilya L. Shapiro; Joan Sola

2007-01-26T23:59:59.000Z

455

Path integral Monte Carlo and density functional molecular dynamics simulations of hot, dense helium  

Science Journals Connector (OSTI)

Two first-principles simulation techniques, path integral Monte Carlo (PIMC) and density functional molecular dynamics (DFT-MD), are applied to study hot, dense helium in the density-temperature range of 0.387–5.35?g?cm?3 and 500?K–1.28×108?K. One coherent equation of state is derived by combining DFT-MD data at lower temperatures with PIMC results at higher temperatures. Good agreement between both techniques is found in an intermediate-temperature range. For the highest temperatures, the PIMC results converge to the Debye-Hückel limiting law. In order to derive the entropy, a thermodynamically consistent free-energy fit is used that reproduces the internal energies and pressure derived from the first-principles simulations. The equation of state is presented in the form of a table as well as a fit and is compared with different free-energy models. Pair-correlation functions and the electronic density of states are discussed. Shock Hugoniot curves are compared with recent laser shock-wave experiments.

B. Militzer

2009-04-08T23:59:59.000Z

456

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

457

Time-dependent density-functional theory for open systems  

E-Print Network [OSTI]

By introducing the self-energy density functionals for the dissipative interactions between the reduced system and its environment, we develop a time-dependent density-functional theory formalism based on an equation of motion for the Kohn-Sham reduced single-electron density matrix of the reduced system. Two approximate schemes are proposed for the self-energy density functionals, the complete second order approximation and the wide-band limit approximation. A numerical method based on the wide-band limit approximation is subsequently developed and implemented to simulate the steady and transient current through various realistic molecular devices. Simulation results are presented and discussed.

Xiao Zheng; Fan Wang; Chi Yung Yam; Yan Mo; GuanHua Chen

2007-02-27T23:59:59.000Z

458

Energy  

Office of Legacy Management (LM)

..) ".. ..) ".. _,; ,' . ' , ,; Depar?.me.nt ,of.' Energy Washington; DC 20585 : . ' , - $$ o"\ ' ~' ,' DEC ?;$ ;y4,,, ~ ' .~ The Honorable John Kalwitz , 200 E. Wells Street Milwaukee, W~isconsin 53202, . . i :. Dear,Mayor 'Kalwitz: " . " Secretary of Energy Hazel' O'Leary has announceha new,approach 'to,openness in " the Department of Ene~rgy (DOE) and its communications with'the public. In -. support of~this initiative, we areipleased to forward the enclosed information related to the Milwaukee Ai.rport site in your jurisdiction that performed work, for DOE orits predecessor agencies. information; use, and retention. ., This information .is provided for your '/ ,' DOE's Formerly Utilized Sites Remedial:'Action~'Prog&is responsible for ,"'

459

Chiral dynamics and peripheral transverse densities  

SciTech Connect (OSTI)

In the partonic (or light-front) description of relativistic systems the electromagnetic form factors are expressed in terms of frame-independent charge and magnetization densities in transverse space. This formulation allows one to identify the chiral components of nucleon structure as the peripheral densities at transverse distances b = O(M{sub {pi}}{sup -1}) and compute them in a parametrically controlled manner. A dispersion relation connects the large-distance behavior of the transverse charge and magnetization densities to the spectral functions of the Dirac and Pauli form factors near the two--pion threshold at timelike t = 4 M{ sub {pi}}{sup 2}, which can be computed in relativistic chiral effective field theory. Using the leading-order approximation we (a) derive the asymptotic behavior (Yukawa tail) of the isovector transverse densities in the "chiral" region b = O(M{sub {pi}}{sup -1}) and the "molecular" region b = O(M{sub N}{sup 2}/M{sub {pi}}{sup 3}); (b) perform the heavy-baryon expansion of the transverse densities; (c) explain the relative magnitude of the peripheral charge and magnetization densities in a simple mechanical picture; (d) include Delta isobar intermediate states and study the peripheral transverse densities in the large-N{ sub c} limit of QCD; (e) quantify the region of transverse distances where the chiral components of the densities are numerically dominant; (f) calculate the chiral divergences of the b{sup 2}-weighted moments of the isovector transverse densities (charge and anomalous magnetic radii) in the limit M{sub {pi}} -> 0 and determine their spatial support. Our approach provides a concise formulation of the spatial structure of the nucleon's chiral component and offers new insights into basic properties of the chiral expansion. It relates the information extracted from low-t elastic form factors to the generalized parton distributions probed in peripheral high-energy scattering processes.

Granados, Carlos G. [Uppsala University (Sweden); Weiss, Christian [JLAB, Newport News, VA (United States)

2014-01-01T23:59:59.000Z

460

The problem of the universal density functional and the density matrix functional theory  

SciTech Connect (OSTI)

The analysis in this paper shows that the Hohenberg-Kohn theorem is the constellation of two statements: (i) the mathematically rigorous Hohenberg-Kohn lemma, which demonstrates that the same ground-state density cannot correspond to two different potentials of an external field, and (ii) the hypothesis of the existence of the universal density functional. Based on the obtained explicit expression for the nonrel-ativistic particle energy in a local external field, we prove that the energy of the system of more than two non-interacting electrons cannot be a functional of the inhomogeneous density. This result is generalized to the system of interacting electrons. It means that the Hohenberg-Kohn lemma cannot provide justification of the universal density functional for fermions. At the same time, statements of the density functional theory remain valid when considering any number of noninteracting ground-state bosons due to the Bose condensation effect. In the framework of the density matrix functional theory, the hypothesis of the existence of the universal density matrix functional corresponds to the cases of noninteracting particles and to interaction in the Hartree-Fock approximation.

Bobrov, V. B., E-mail: vic5907@mail.ru; Trigger, S. A., E-mail: satron@mail.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

2013-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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

Gravitational energy  

E-Print Network [OSTI]

Observers at rest in a stationary spacetime flat at infinity can measure small amounts of rest-mass+internal energies+kinetic energies+pressure energy in a small volume of fluid attached to a local inertial frame. The sum of these small amounts is the total "matter energy" for those observers. The total mass-energy minus the matter energy is the binding gravitational energy. Misner, Thorne and Wheeler evaluated the gravitational energy of a spherically symmetric static spacetime. Here we show how to calculate gravitational energy in any static and stationary spacetime for isolated sources with a set of observers at rest. The result of MTW is recovered and we find that electromagnetic and gravitational 3-covariant energy densities in conformastatic spacetimes are of opposite signs. Various examples suggest that gravitational energy is negative in spacetimes with special symmetries or when the energy-momentum tensor satisfies usual energy conditions.

Joseph Katz

2005-10-20T23:59:59.000Z

462

Density dependence of reactor performance with thermal confinement scalings  

SciTech Connect (OSTI)

Energy confinement scalings for the thermal component of the plasma published thus far have a different dependence on plasma density and input power than do scalings for the total plasma energy. With such thermal scalings, reactor performance (measured by Q, the ratio of the fusion power to the sum of the ohmic and auxiliary input powers) worsens with increasing density. This dependence is the opposite of that found using scalings based on the total plasma energy, indicating that reactor operation concepts may need to be altered if this density dependence is confirmed in future research.

Stotler, D.P.

1992-03-01T23:59:59.000Z

463

Fraud in For-Profit Higher Education  

Science Journals Connector (OSTI)

The rising prominence of for-profit higher education in recent years has been impressive, as these organizations have come to play a more prominent role in American higher education. Nonetheless, for-profits c...

William Beaver

2012-05-01T23:59:59.000Z

464

Surface properties of liquid mercury: a comparison of density-dependent and density-independent force fields  

E-Print Network [OSTI]

The surface properties of liquid mercury (Hg) at a temperature of 293 K are investigated by classical Molecular Dynamics simulation using density-independent (DI) and density-dependent (DD) force fields. The latter force fields were introduced to improve the description of surface properties. Both force fields yield lower values of the surface tension in comparison to experimental data. Moreover, the density-dependent force field results in an anomalous thermodynamic behavior. These findings are rationalized by liquid-state theory. An optimized, density-independent force field is proposed that yields a higher surface tension and, at the same time, provides an accurate description of the liquid-vapor coexistence.

A. Iakovlev; D. Bedrov; M. Müller

2014-12-08T23:59:59.000Z

465

Density Perturbations in the Ekpyrotic Scenario  

E-Print Network [OSTI]

We study the generation of density perturbations in the ekpyrotic scenario for the early universe, including gravitational backreaction. We expose interesting subtleties that apply to both inflationary and ekpyrotic models. Our analysis includes a detailed proposal of how the perturbations generated in a contracting phase may be matched across a `bounce' to those in an expanding hot big bang phase. For the physical conditions relevant to the ekpyrotic scenario, we re-obtain our earlier result of a nearly scale-invariant spectrum of energy density perturbations. We find that the perturbation amplitude is typically small, as desired to match observation.

Justin Khoury; Burt A. Ovrut; Paul J. Steinhardt; Neil Turok

2001-09-06T23:59:59.000Z

466

CX-006508: Categorical Exclusion Determination | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

8: Categorical Exclusion Determination 8: Categorical Exclusion Determination CX-006508: Categorical Exclusion Determination Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500 Watthours per Liter CX(s) Applied: A1, A8, A9 Date: 08/25/2011 Location(s): Midland, Michigan Office(s): Energy Efficiency and Renewable Energy, National Energy Technology Laboratory The objective of this work is to develop and optimize new materials and cells that will increase the energy density of cells to greater than 600-750 Watthours per liter while maintaining or improving all other cell performance characteristics. DOCUMENT(S) AVAILABLE FOR DOWNLOAD CX-006508.pdf More Documents & Publications CX-000324: Categorical Exclusion Determination CX-000312: Categorical Exclusion Determination

467

Crystallization of polyethylene by modified weighted density approximation(MWDA)  

E-Print Network [OSTI]

In this article, we use the modified weighted density approximation to study the crystallization of polyethylene. We also use a direct correlation function of polyethylene based on RISM theory. The free energy of a polyethylene is calculated using density functional theory. The crystallization and solid and liquid density are calculated and finally compared with the prism simulation and experimental results. That shown the result obtained by MWDA is in better agreement, compared with the experimental result than the prism.

Razeghizadeh, Alireza; Lavafpour, Farhad

2015-01-01T23:59:59.000Z

468

Crystallization of polyethylene by modified weighted density approximation(MWDA)  

E-Print Network [OSTI]

In this article, we use the modified weighted density approximation to study the crystallization of polyethylene. We also use a direct correlation function of polyethylene based on RISM theory. The free energy of a polyethylene is calculated using density functional theory. The crystallization and solid and liquid density are calculated and finally compared with the prism simulation and experimental results. That shown the result obtained by MWDA is in better agreement, compared with the experimental result than the prism.

Alireza Razeghizadeh; Vahdat Rafee; Farhad Lavafpour

2015-02-07T23:59:59.000Z

469

DISCLAIMER: | Department of Energy  

Office of Environmental Management (EM)

DISCLAIMER: DISCLAIMER: DISCLAIMER: More Documents & Publications Recovery Act: Wind Energy Consortia between Institutions of Higher Learning and Industry Microsoft Word -...

470

California | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

, 2011 , 2011 Berkeley Lab: 80 Years of Excellence in Science Congratulations to Lawrence Berkeley National Laboratory, which celebrated its 80th anniversary on August 26. September 1, 2011 EIS-0455: Record of Decision Genesis Solar Energy Project, Riverside County, California September 1, 2011 How to See the Supernova Berkeley Lab Just Discovered According to astronomers, this is the closest and brightest supernova of this type detected in the last 30 years and will be closely studied for years to come. In this video, Berkeley Lab's Peter Nugent explains how to find the event with a small telescope or pair of binoculars. August 25, 2011 CX-006510: Categorical Exclusion Determination Development of Large Format Lithium Ion Cells with Higher Energy Density Exceeding 500 Watthours per Liter

471

Theoretical power density from salinity gradients using reverse electrodialysis  

Science Journals Connector (OSTI)

Reverse electrodialysis (RED) is a technology to generate power from mixing waters with different salinity. The net power density (i.e. power per membrane area) is determined by 1) the membrane potential, 2) the ohmic resistance, 3) the resistance due to changing bulk concentrations, 4) the boundary layer resistance and 5) the power required to pump the feed water. Previous power density estimations often neglected the latter three terms. This paper provides a set of analytical equations to estimate the net power density obtainable from RED stacks with spacers and RED stacks with profiled membranes. With the current technology, the obtained maximum net power density is calculated at 2.7 W/m2. Higher power densities could be obtained by changing the cell design, in particular the membrane resistance and the cell length. Changing these parameters one and two orders of magnitude respectively, the calculated net power density is close to 20 W/m2.

David A. Vermaas; Enver Guler; Michel Saakes; Kitty Nijmeijer

2012-01-01T23:59:59.000Z

472

Complex structure of electron and density functional theory  

E-Print Network [OSTI]

Effective model for electron as two particle system is considered. The first particle in the system is chargeless mass of electron. The second one is massless charge of electron. Based on this model it is shown that density of energy for the particle is proportional to the probability density and the following formula stands $\\rho_E(x)=mc^2\\rho(x)$.

K. Koshelev

2013-01-08T23:59:59.000Z

473

Irradiation effects in high-density polyethylene Jussi Polvia  

E-Print Network [OSTI]

Irradiation effects in high-density polyethylene Jussi Polvia , Kai Nordlunda a simulations, we have studied the irradiation effects in high density polyethylene. We determined the threshold energy for creating defects in the polyethylene lattice as a function of the incident angle. We found

Nordlund, Kai

474

Effect of air density variations on greenhouse temperature model  

Science Journals Connector (OSTI)

Basically, a greenhouse temperature model is determined based on the balances of mass and energy. In most of the available models, the air density is considered constant. This fact limits the model because of the natural existing relationship between ... Keywords: Air density, Greenhouse, Humidity, Nonlinear systems, Temperature

Javier Leal Iga; Jorge Leal Iga; Carlos Leal Iga; Ramiro Ayala Flores

2008-05-01T23:59:59.000Z

475

Higher Order Maximum Persistency and Comparison Theorems  

E-Print Network [OSTI]

discrete variables (energy minimization in graphical models, weighted constraint ... 1.2 Energy Minimization . ...... This is useful in proofs, providing an alternative.

2014-10-15T23:59:59.000Z

476

The Dynamical Properties Derived from the More Generalized Lagrangian Density for A Gravitational System  

E-Print Network [OSTI]

The studies of the generalized Einstein Lagrangian densities without torsion are extended to those of the more generalized Lagrangian densities with torsion. The properties of the more generalized Lagrangian densities are studied systematically and thoroughly. The dynamical laws of a gravitational system such as the gravitational field equations, the conservation laws of the energy-momentum tensor densities, the conservation laws of the spin densities and the equations of motion for test particle are all derived from the Lagrangian densities. The differences between the more generalized Lagrangian densities and the generalized Einstein Lagrangian densities are discussed.

Fang-Pei Chen

2007-05-22T23:59:59.000Z

477

Assessing the performance of recent density functionals for bulk solids  

E-Print Network [OSTI]

We assess the performance of recent density functionals for the exchange-correlation energy of a nonmolecular solid, by applying accurate calculations with the GAUSSIAN, BAND, and VASP codes to a test set of 24 solid metals ...

Csonka, Gabor I.

478

The gravimetric density formula for a spherical shell  

Science Journals Connector (OSTI)

...Hearst, 1977). ACKNOWLEDGMENTS This work was performed under the auspices of the U .S . Energy Research and Developm ent Adm inis tration, under contract No. W -7405-Eng-48. REFERENCES Hammer, S., 1950, Density determinations by underground gravity...

J. R. Hearst; R. C. Carlson

479

Density Evolution in the New Modified Chaplygin Gas Model  

E-Print Network [OSTI]

In this paper, we have considered new modified Chaplygin gas (NMCG) model which interpolates between radiation at early stage and $\\Lambda$CDM at late stage. This model is regarded as a unification of dark energy and dark matter (with general form of matter). We have derived the density parameters from the equation of motion for the interaction between dark energy and dark matter. Also we have studied the evolution of the various components of density parameters.

Surajit Chattopadhyay; Ujjal Debnath

2008-05-01T23:59:59.000Z

480

THE STAR FORMATION LAW AT LOW SURFACE DENSITY  

SciTech Connect (OSTI)

We investigate the nature of the star formation law at low gas surface densities using a sample of 19 low surface brightness (LSB) galaxies with existing H I maps in the literature, UV imaging from the Galaxy Evolution Explorer satellite, and optical images from the Sloan Digital Sky Survey. All of the LSB galaxies have (NUV - r) colors similar to those for higher surface brightness star-forming galaxies of similar luminosity indicating that their average star formation histories are not very different. Based upon four LSB galaxies with both UV and far-infrared (FIR) data, we find FIR/UV ratios significantly less than 1, implying low amounts of internal UV extinction in LSB galaxies. We use the UV images and H I maps to measure the star formation rate (SFR) and hydrogen gas surface density within the same region for all the galaxies. The LSB galaxy star formation rate surface densities lie below the extrapolation of the power law fit to the SFR surface density as a function of the total gas density for higher surface brightness galaxies. Although there is more scatter, the LSB galaxies also lie below a second version of the star formation law in which the SFR surface density is correlated with the gas density divided by the orbital time in the disk. The downturn seen in both star formation laws is consistent with theoretical models that predict lower star formation efficiencies in LSB galaxies due to the declining molecular fraction with decreasing density.

Wyder, Ted K.; Martin, D. Christopher; Barlow, Tom A.; Foster, Karl; Friedman, Peter G.; Morrissey, Patrick; Neill, James D. [California Institute of Technology, MC 278-17, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Neff, Susan G. [Laboratory for Astronomy and Solar Physics, NASA Goddard Space Flight Center, Greenbelt, MD, 20771 (United States); Schiminovich, David [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Seibert, Mark; Madore, Barry F. [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Bianchi, Luciana [Center for Astrophysical Sciences, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218 (United States); Donas, Jose; Milliard, Bruno [Laboratoire d'Astrophysique de Marseille, BP 8, Traverse du Siphon, 13376 Marseille Cedex 12 (France); Heckman, Timothy M.; Szalay, Alex S. [Department of Physics and Astronomy, Johns Hopkins University, Homewood Campus, Baltimore, MD 21218 (United States); Lee, Young-Wook; Yi, Sukyoung K. [Center for Space Astrophysics, Yonsei University, Seoul 120-749 (Korea, Republic of); Rich, R. Michael [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)

2009-05-10T23:59:59.000Z

Note: This page contains sample records for the topic "higher energy 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.