National Library of Energy BETA

Sample records for distribution type constant

  1. Determination of plasma frequency, damping constant, and size distribution from the complex dielectric function of noble metal nanoparticles

    SciTech Connect (OSTI)

    Mendoza Herrera, Luis J.; Arboleda, David Muetn; Schinca, Daniel C.; Scaffardi, Luca B.

    2014-12-21

    This paper develops a novel method for simultaneously determining the plasma frequency ?{sub P}?? and the damping constant ?{sub free} in the bulk damped oscillator Drude model, based on experimentally measured real and imaginary parts of the metal refractive index in the IR wavelength range, lifting the usual approximation that restricts frequency values to the UV-deep UV region. Our method was applied to gold, silver, and copper, improving the relative uncertainties in the final values for ?{sub p} (0.5%1.6%) and for ?{sub free} (3%8%), which are smaller than those reported in the literature. These small uncertainties in ?{sub p} and ?{sub free} determination yield a much better fit of the experimental complex dielectric function. For the case of nanoparticles (Nps), a series expansion of the Drude expression (which includes ?{sub p} and ?{sub free} determined using our method) enables size-dependent dielectric function to be written as the sum of three terms: the experimental bulk dielectric function plus two size corrective terms, one for free electron, and the other for bound-electron contributions. Finally, size distribution of nanometric and subnanometric gold Nps in colloidal suspension was determined through fitting its experimental optical extinction spectrum using Mie theory based on the previously determined dielectric function. Results are compared with size histogram obtained from Transmission Electron Microscopy (TEM)

  2. Perspectives on distributed computing : thirty people, four user types, and the distributed computing user experience.

    SciTech Connect (OSTI)

    Childers, L.; Liming, L.; Foster, I.; Mathematics and Computer Science; Univ. of Chicago

    2008-10-15

    ) A method for characterizing users according to their technology interactions, and identification of four user types among the interviewees using the method; (3) Four profiles that highlight points of commonality and diversity in each user type; (4) Recommendations for technology developers and future studies; (5) A description of the interview protocol and overall study methodology; (6) An anonymized list of the interviewees; and (7) Interview writeups and summary data. The interview summaries in Section 3 and transcripts in Appendix D illustrate the value of distributed computing software--and Globus in particular--to scientific enterprises. They also document opportunities to make these tools still more useful both to current users and to new communities. We aim our recommendations at developers who intend their software to be used and reused in many applications. (This kind of software is often referred to as 'middleware.') Our two core recommendations are as follows. First, it is essential for middleware developers to understand and explicitly manage the multiple user products in which their software components are used. We must avoid making assumptions about the commonality of these products and, instead, study and account for their diversity. Second, middleware developers should engage in different ways with different kinds of users. Having identified four general user types in Section 4, we provide specific ideas for how to engage them in Section 5.

  3. Remote sensing-based characterization, 2-m, Plant Functional Type Distributions, Barrow Environmental Observatory, 2010

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

    Zachary Langford; Forrest Hoffman; Jitendra Kumar

    Arctic ecosystems have been observed to be warming faster than the global average and are predicted to experience accelerated changes in climate due to global warming. Arctic vegetation is particularly sensitive to warming conditions and likely to exhibit shifts in species composition, phenology and productivity under changing climate. Mapping and monitoring of changes in vegetation is essential to understand the effect of climate change on the ecosystem functions. Vegetation exhibits unique spectral characteristics which can be harnessed to discriminate plant types and develop quantitative vegetation indices. We have combined high resolution multi-spectral remote sensing from the WorldView 2 satellite with LIDAR-derived digital elevation models to characterize the tundra landscape on the North Slope of Alaska. Classification of landscape using spectral and topographic characteristics yields spatial regions with expectedly similar vegetation characteristics. A field campaign was conducted during peak growing season to collect vegetation harvests from a number of 1m x 1m plots in the study region, which were then analyzed for distribution of vegetation types in the plots. Statistical relationships were developed between spectral and topographic characteristics and vegetation type distributions at the vegetation plots. These derived relationships were employed to statistically upscale the vegetation distributions for the landscape based on spectral characteristics. Vegetation distributions developed are being used to provide Plant Functional Type (PFT) maps for use in the Community Land Model (CLM).

  4. Remote sensing-based characterization of plant functional type distributions at the Barrow Environmental Observatory

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

    Kumar, Jitendra; Hoffman, Forrest M.

    Arctic ecosystems have been observed to be warming faster than the global average and are predicted to experience accelerated changes in climate due to global warming. Arctic vegetation is particularly sensitive to warming conditions and likely to exhibit shifts in species composition, phenology and productivity under changing climate. Mapping and monitoring of changes in vegetation is essential to understand the effect of climate change on the ecosystem functions. Vegetation exhibits unique spectral characteristics which can be harnessed to discriminate plant types and develop quantitative vegetation indices. We have combined high resolution multi-spectral remote sensing from the WorldView 2 satellite with LIDAR-derived digital elevation models to characterize the tundra landscape on the North Slope of Alaska. Classification of landscape using spectral and topographic characteristics yields spatial regions with expectedly similar vegetation characteristics. A field campaign was conducted during peak growing season to collect vegetation harvests from a number of 1m x 1m plots in the study region, which were then analyzed for distribution of vegetation types in the plots. Statistical relationships were developed between spectral and topographic characteristics and vegetation type distributions at the vegetation plots. These derived relationships were employed to statistically upscale the vegetation distributions for the landscape based on spectral characteristics. Vegetation distributions developed are being used to provide Plant Functional Type (PFT) maps for use in the Community Land Model (CLM).

  5. Remote sensing-based characterization, 2-m, Plant Functional Type Distributions, Barrow Environmental Observatory, 2010

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

    Zachary Langford; Forrest Hoffman; Jitendra Kumar

    2014-01-01

    Arctic ecosystems have been observed to be warming faster than the global average and are predicted to experience accelerated changes in climate due to global warming. Arctic vegetation is particularly sensitive to warming conditions and likely to exhibit shifts in species composition, phenology and productivity under changing climate. Mapping and monitoring of changes in vegetation is essential to understand the effect of climate change on the ecosystem functions. Vegetation exhibits unique spectral characteristics which can be harnessed to discriminate plant types and develop quantitative vegetation indices. We have combined high resolution multi-spectral remote sensing from the WorldView 2 satellite with LIDAR-derived digital elevation models to characterize the tundra landscape on the North Slope of Alaska. Classification of landscape using spectral and topographic characteristics yields spatial regions with expectedly similar vegetation characteristics. A field campaign was conducted during peak growing season to collect vegetation harvests from a number of 1m x 1m plots in the study region, which were then analyzed for distribution of vegetation types in the plots. Statistical relationships were developed between spectral and topographic characteristics and vegetation type distributions at the vegetation plots. These derived relationships were employed to statistically upscale the vegetation distributions for the landscape based on spectral characteristics. Vegetation distributions developed are being used to provide Plant Functional Type (PFT) maps for use in the Community Land Model (CLM).

  6. Remote sensing-based characterization of plant functional type distributions at the Barrow Environmental Observatory

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

    Kumar, Jitendra; Hoffman, Forrest M.

    2014-03-18

    Arctic ecosystems have been observed to be warming faster than the global average and are predicted to experience accelerated changes in climate due to global warming. Arctic vegetation is particularly sensitive to warming conditions and likely to exhibit shifts in species composition, phenology and productivity under changing climate. Mapping and monitoring of changes in vegetation is essential to understand the effect of climate change on the ecosystem functions. Vegetation exhibits unique spectral characteristics which can be harnessed to discriminate plant types and develop quantitative vegetation indices. We have combined high resolution multi-spectral remote sensing from the WorldView 2 satellite with LIDAR-derived digital elevation models to characterize the tundra landscape on the North Slope of Alaska. Classification of landscape using spectral and topographic characteristics yields spatial regions with expectedly similar vegetation characteristics. A field campaign was conducted during peak growing season to collect vegetation harvests from a number of 1m x 1m plots in the study region, which were then analyzed for distribution of vegetation types in the plots. Statistical relationships were developed between spectral and topographic characteristics and vegetation type distributions at the vegetation plots. These derived relationships were employed to statistically upscale the vegetation distributions for the landscape based on spectral characteristics. Vegetation distributions developed are being used to provide Plant Functional Type (PFT) maps for use in the Community Land Model (CLM).

  7. TYPE Ia SUPERNOVA COLORS AND EJECTA VELOCITIES: HIERARCHICAL BAYESIAN REGRESSION WITH NON-GAUSSIAN DISTRIBUTIONS

    SciTech Connect (OSTI)

    Mandel, Kaisey S.; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Foley, Ryan J., E-mail: kmandel@cfa.harvard.edu [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States)

    2014-12-20

    We investigate the statistical dependence of the peak intrinsic colors of Type Ia supernovae (SNe Ia) on their expansion velocities at maximum light, measured from the Si II ?6355 spectral feature. We construct a new hierarchical Bayesian regression model, accounting for the random effects of intrinsic scatter, measurement error, and reddening by host galaxy dust, and implement a Gibbs sampler and deviance information criteria to estimate the correlation. The method is applied to the apparent colors from BVRI light curves and Si II velocity data for 79 nearby SNe Ia. The apparent color distributions of high-velocity (HV) and normal velocity (NV) supernovae exhibit significant discrepancies for B V and B R, but not other colors. Hence, they are likely due to intrinsic color differences originating in the B band, rather than dust reddening. The mean intrinsic B V and B R color differences between HV and NV groups are 0.06 0.02 and 0.09 0.02 mag, respectively. A linear model finds significant slopes of 0.021 0.006 and 0.030 0.009 mag (10{sup 3} km s{sup 1}){sup 1} for intrinsic B V and B R colors versus velocity, respectively. Because the ejecta velocity distribution is skewed toward high velocities, these effects imply non-Gaussian intrinsic color distributions with skewness up to +0.3. Accounting for the intrinsic-color-velocity correlation results in corrections to A{sub V} extinction estimates as large as 0.12 mag for HV SNe Ia and +0.06 mag for NV events. Velocity measurements from SN Ia spectra have the potential to diminish systematic errors from the confounding of intrinsic colors and dust reddening affecting supernova distances.

  8. Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at $\\sqrt{s}$ = 7 TeV

    SciTech Connect (OSTI)

    Khachatryan, Vardan

    2014-10-27

    The inclusive jet cross section for proton-proton collisions at a centre-of-mass energy of 7$~\\mathrm{TeV}$ was measured by the CMS Collaboration at the LHC with data corresponding to an integrated luminosity of 5.0$~\\mathrm{fb}^{-1}$. The measurement covers a phase space up to 2$~\\mathrm{TeV}$ in jet transverse momentum and 2.5 in absolute jet rapidity. The statistical precision of these data leads to stringent constraints on the parton distribution functions of the proton. The data provide important input for the gluon density at high fractions of the proton momentum and for the strong coupling constant at large energy scales. Using predictions from perturbative quantum chromodynamics at next-to-leading order, complemented with electroweak corrections, the constraining power of these data is investigated and the strong coupling constant at the Z boson mass $M_{\\mathrm{Z}}$ is determined to be $\\alpha_S(M_{\\mathrm{Z}}) = 0.1185 \\pm 0.0019\\,(\\mathrm{exp})\\,^{+0.0060}_{-0.0037}\\,(\\mathrm{theo})$, which is in agreement with the world average.

  9. Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at $\\sqrt{s}$ = 7 TeV

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

    Khachatryan, Vardan

    2014-10-27

    The inclusive jet cross section for proton-proton collisions at a centre-of-mass energy of 7$~\\mathrm{TeV}$ was measured by the CMS Collaboration at the LHC with data corresponding to an integrated luminosity of 5.0$~\\mathrm{fb}^{-1}$. The measurement covers a phase space up to 2$~\\mathrm{TeV}$ in jet transverse momentum and 2.5 in absolute jet rapidity. The statistical precision of these data leads to stringent constraints on the parton distribution functions of the proton. The data provide important input for the gluon density at high fractions of the proton momentum and for the strong coupling constant at large energy scales. Using predictions from perturbative quantummorechromodynamics at next-to-leading order, complemented with electroweak corrections, the constraining power of these data is investigated and the strong coupling constant at the Z boson mass $M_{\\mathrm{Z}}$ is determined to be $\\alpha_S(M_{\\mathrm{Z}}) = 0.1185 \\pm 0.0019\\,(\\mathrm{exp})\\,^{+0.0060}_{-0.0037}\\,(\\mathrm{theo})$, which is in agreement with the world average.less

  10. Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at $$\\sqrt{s} = 7$$ $$\\,\\text {TeV}$$

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

    Khachatryan, Vardan

    2015-06-26

    The inclusive jet cross section for proton–proton collisions at a centre-of-mass energy of 7TeVwas measured by the CMS Collaboration at the LHC with data corresponding to an integrated luminosity of 5.0fb-1. The measurement covers a phase space up to 2TeV in jet transverse momentum and 2.5 in absolute jet rapidity. The statistical precision of these data leads to stringent constraints on the parton distribution functions of the proton. The data provide important input for the gluon density at high fractions of the proton momentum and for the strong coupling constant at large energy scales. Using predictions from perturbative quantum chromodynamicsmore » at next-to-leading order, complemented with electroweak corrections, the constraining power of these data is investigated and the strong coupling constant at the Z boson mass MZ is determined to be αS(MZ)=0.1185±0.0019(exp)+0.0060-0.0037(theo), which is in agreement with the world average.« less

  11. Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at $\\sqrt{s} = 7$ $\\,\\text {TeV}$

    SciTech Connect (OSTI)

    Khachatryan, Vardan

    2015-06-26

    The inclusive jet cross section for proton–proton collisions at a centre-of-mass energy of 7TeVwas measured by the CMS Collaboration at the LHC with data corresponding to an integrated luminosity of 5.0fb-1. The measurement covers a phase space up to 2TeV in jet transverse momentum and 2.5 in absolute jet rapidity. The statistical precision of these data leads to stringent constraints on the parton distribution functions of the proton. The data provide important input for the gluon density at high fractions of the proton momentum and for the strong coupling constant at large energy scales. Using predictions from perturbative quantum chromodynamics at next-to-leading order, complemented with electroweak corrections, the constraining power of these data is investigated and the strong coupling constant at the Z boson mass MZ is determined to be αS(MZ)=0.1185±0.0019(exp)+0.0060-0.0037(theo), which is in agreement with the world average.

  12. THE INTEGRAL HIGH-ENERGY CUT-OFF DISTRIBUTION OF TYPE 1 ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Malizia, A.; Molina, M.; Bassani, L.; Stephen, J. B.; Bazzano, A.; Ubertini, P.; Bird, A. J.

    2014-02-20

    In this Letter we present the primary continuum parameters, the photon index Γ, and the high-energy cut-off E {sub c} of 41 type-1 Seyfert galaxies extracted from the International Gamma-Ray Astrophysics Laboratory (INTEGRAL) complete sample of active galactic nuclei (AGNs). We performed broadband (0.3-100 keV) spectral analysis by simultaneously fitting the soft and hard X-ray spectra obtained by XMM and INTEGRAL/IBIS-Swift/BAT, respectively, in order to investigate the general properties of these parameters, in particular their distribution and mean values. We find a mean photon index of 1.73 with a standard deviation of 0.17 and a mean high-energy cut-off of 128 keV with a standard deviation of 46 keV for the whole sample. This is the first time that the cut-off energy is constrained in such a large number of AGNs. We have 26 measurements of the cut-off, which corresponds to 63% of the entire sample, distributed between 50 and 200 keV. There are a further 11 lower limits mostly below 300 keV. Using the main parameters of the primary continuum, we have been able to obtain the actual physical parameters of the Comptonizing region, i.e., the plasma temperature kT {sub e} from 20 to 100 keV and the optical depth τ < 4. Finally, with the high signal-to-noise ratio spectra starting to come from NuSTAR it will soon be possible to better constrain the cut-off values in many AGNs, allowing the determination of more physical models and thus better understand the continuum emission and geometry of the region surrounding black holes.

  13. XrayOpticsConstants

    Energy Science and Technology Software Center (OSTI)

    2005-06-20

    This application (XrayOpticsConstants) is a tool for displaying X-ray and Optical properties for a given material, x-ray photon energy, and in the case of a gas, pressure. The display includes fields such as the photo-electric absorption attenuation length, density, material composition, index of refraction, and emission properties (for scintillator materials).

  14. Distribution:

    Office of Legacy Management (LM)

    JAN26 19% Distribution: OR00 Attn: h.H.M.Roth DFMusser ITMM MMMann INS JCRyan FIw(2) Hsixele SRGustavson, Document rocm Formal file i+a@mmm bav@ ~@esiaw*cp Suppl. file 'Br & Div rf's s/health (lic.only) UNITED STATES ATOMIC ENERGY COMMISSION SPECIAL NUCLEAB MATERIAL LICENSE pursuant to the Atomic Energy Act of 1954 and Title 10, Code of Federal Regulations, Chapter 1, P&t 70, "Special Nuclear Material Reg)llatiqm," a license is hereby issued a$hortztng the licensee to rekeive

  15. Pressure distribution along the AGS vacuum chambers with new types of pump out conduits

    SciTech Connect (OSTI)

    Nayak, S.; Mapes, M.; Smart, L.; Weiss, D.

    2015-10-28

    The AGS HEBT and ring vacuum system is monitored by the discharge current of the magnet ion pumps, which is proportional to the pressure at the inlet port of these ion pumps. The discharge current is measured and suitably calibrated to indicate the ion pump pressure. In order to calculate the vacuum chamber pressure from the ion pump pressure, a detailed analysis is essential to compute their difference in different scenarios. Such analysis has been carried out numerically in the past for the system with the older type of pump out conduits, and similar analysis using FEM in ANSYS is presented in this paper with the newer type of pump out conduit.

  16. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    SciTech Connect (OSTI)

    Davies, D.K.; Vessell, R.K.; Doublet, L.E.

    1997-08-01

    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  17. Unitaxial constant velocity microactuator

    DOE Patents [OSTI]

    McIntyre, T.J.

    1994-06-07

    A uniaxial drive system or microactuator capable of operating in an ultra-high vacuum environment is disclosed. The mechanism includes a flexible coupling having a bore therethrough, and two clamp/pusher assemblies mounted in axial ends of the coupling. The clamp/pusher assemblies are energized by voltage-operated piezoelectrics therewithin to operatively engage the shaft and coupling causing the shaft to move along its rotational axis through the bore. The microactuator is capable of repeatably positioning to sub-nanometer accuracy while affording a scan range in excess of 5 centimeters. Moreover, the microactuator generates smooth, constant velocity motion profiles while producing a drive thrust of greater than 10 pounds. The system is remotely controlled and piezoelectrically driven, hence minimal thermal loading, vibrational excitation, or outgassing is introduced to the operating environment. 10 figs.

  18. Unitaxial constant velocity microactuator

    DOE Patents [OSTI]

    McIntyre, Timothy J.

    1994-01-01

    A uniaxial drive system or microactuator capable of operating in an ultra-high vacuum environment. The mechanism includes a flexible coupling having a bore therethrough, and two clamp/pusher assemblies mounted in axial ends of the coupling. The clamp/pusher assemblies are energized by voltage-operated piezoelectrics therewithin to operatively engage the shaft and coupling causing the shaft to move along its rotational axis through the bore. The microactuator is capable of repeatably positioning to sub-manometer accuracy while affording a scan range in excess of 5 centimeters. Moreover, the microactuator generates smooth, constant velocity motion profiles while producing a drive thrust of greater than 10 pounds. The system is remotely controlled and piezoelectrically driven, hence minimal thermal loading, vibrational excitation, or outgassing is introduced to the operating environment.

  19. Electric cartridge-type heater for producing a given non-uniform axial power distribution

    DOE Patents [OSTI]

    Clark, D.L.; Kress, T.S.

    1975-10-14

    An electric cartridge heater is provided to simulate a reactor fuel element for use in safety and thermal-hydraulic tests of model nuclear reactor systems. The electric heat-generating element of the cartridge heater consists of a specifically shaped strip of metal cut with variable width from a flat sheet of the element material. When spirally wrapped around a mandrel, the strip produces a coiled element of the desired length and diameter. The coiled element is particularly characterized by an electrical resistance that varies along its length due to variations in strip width. Thus, the cartridge heater is constructed such that it will produce a more realistic simulation of the actual nonuniform (approximately ''chopped'' cosine) power distribution of a reactor fuel element.

  20. QCD coupling constants and VDM

    SciTech Connect (OSTI)

    Erkol, G.; Ozpineci, A.; Zamiralov, V. S.

    2012-10-23

    QCD sum rules for coupling constants of vector mesons with baryons are constructed. The corresponding QCD sum rules for electric charges and magnetic moments are also derived and with the use of vector-meson-dominance model related to the coupling constants. The VDM role as the criterium of reciprocal validity of the sum rules is considered.

  1. SPECTRAL ENERGY DISTRIBUTIONS OF TYPE 1 ACTIVE GALACTIC NUCLEI IN THE COSMOS SURVEY. I. THE XMM-COSMOS SAMPLE

    SciTech Connect (OSTI)

    Elvis, M.; Hao, H.; Civano, F.; Brusa, M.; Salvato, M.; Bongiorno, A.; Cappelluti, N.; Capak, P.; Zamorani, G.; Comastri, A.; Gilli, R.; Jahnke, K.; Lusso, E.; Cisternas, M.; Mainieri, V.; Trump, J. R.; Ho, L. C.; Aussel, H.; Frayer, D.; Hasinger, G. E-mail: hhao@cfa.harvard.edu; and others

    2012-11-01

    The 'Cosmic Evolution Survey' (COSMOS) enables the study of the spectral energy distributions (SEDs) of active galactic nuclei (AGNs) because of the deep coverage and rich sampling of frequencies from X-ray to radio. Here we present an SED catalog of 413 X-ray (XMM-Newton)-selected type 1 (emission line FWHM > 2000 km s{sup -1}) AGNs with Magellan, SDSS, or VLT spectrum. The SEDs are corrected for Galactic extinction, broad emission line contributions, constrained variability, and host galaxy contribution. We present the mean SED and the dispersion SEDs after the above corrections in the rest-frame 1.4 GHz to 40 keV, and show examples of the variety of SEDs encountered. In the near-infrared to optical (rest frame {approx}8 {mu}m-4000 A), the photometry is complete for the whole sample and the mean SED is derived from detections only. Reddening and host galaxy contamination could account for a large fraction of the observed SED variety. The SEDs are all available online.

  2. Angular distribution of energetic argon ions emitted by a 90 kJ Filippov-type plasma focus

    SciTech Connect (OSTI)

    Pestehe, S. J.; Mohammadnejad, M.

    2015-02-15

    Characteristics of the energetic argon ions emitted by a 90 kJ Filippov-type plasma focus are studied by employing an array of Faraday cups. The Faraday cups are designed to minimize the secondary electron emission effects on their response. Angular distribution of the ions is measured, and the results indicate a highly anisotropic emission with a dip at the device axis and a local maximum at the angle of 7° with respect to the axis. It has been argued that this kind of anisotropic emission may be related to the surfatron acceleration mechanism and shown that this behavior is independent of the working gas pressure. It has been also demonstrated that this mechanism is responsible for the generation of MeV ions. Measuring the total ion number at different working gas pressures gives an optimum pressure of 0.3 Torr. In addition, the energy spectrum of ions is measured by taking into account of the ambient gas effects on the energy and charge of the ions. The current neutralization effect of electrons trapped in the ion beam as well as the effect of conducting boundaries surrounding the beam, on the detected signals are investigated.

  3. The 1% concordance Hubble constant

    SciTech Connect (OSTI)

    Bennett, C. L.; Larson, D.; Weiland, J. L.; Hinshaw, G.

    2014-10-20

    The determination of the Hubble constant has been a central goal in observational astrophysics for nearly a hundred years. Extraordinary progress has occurred in recent years on two fronts: the cosmic distance ladder measurements at low redshift and cosmic microwave background (CMB) measurements at high redshift. The CMB is used to predict the current expansion rate through a best-fit cosmological model. Complementary progress has been made with baryon acoustic oscillation (BAO) measurements at relatively low redshifts. While BAO data do not independently determine a Hubble constant, they are important for constraints on possible solutions and checks on cosmic consistency. A precise determination of the Hubble constant is of great value, but it is more important to compare the high and low redshift measurements to test our cosmological model. Significant tension would suggest either uncertainties not accounted for in the experimental estimates or the discovery of new physics beyond the standard model of cosmology. In this paper we examine in detail the tension between the CMB, BAO, and cosmic distance ladder data sets. We find that these measurements are consistent within reasonable statistical expectations and we combine them to determine a best-fit Hubble constant of 69.6 ± 0.7 km s{sup –1} Mpc{sup –1}. This value is based upon WMAP9+SPT+ACT+6dFGS+BOSS/DR11+H {sub 0}/Riess; we explore alternate data combinations in the text. The combined data constrain the Hubble constant to 1%, with no compelling evidence for new physics.

  4. Distribution change of oxygen vacancies in layered perovskite type(Sr, La){sub n+1}Fe{sub n}O{sub 3n+1} (n=3)

    SciTech Connect (OSTI)

    Kagomiya, Isao Jimbo, Keigo; Kakimoto, Ken-ichi

    2013-11-15

    To elucidate characteristic oxygen vacancy formation in layered perovskite (Sr, La){sub n+1}Fe{sub n}O{sub 3n+1} with the perovskite layer number: n=3, oxygen vacancy content ? of the (Sr{sub 0.775}La{sub 0.225}){sub 4}Fe{sub 3}O{sub 10??} (SLF4310) was investigated using a titration technique and a thermogravimetric analysis. The equilibrium constant K for the reduction reaction: Oo{sup }+2Fe{sub Fe}{sup ?} (Fe{sup 4+})=1/2O{sub 2}+Vo{sup ??}+2Fe{sub Fe}{sup }(Fe{sup 3+}) was estimated using the vacancy content ?. The Arrhenius plot of the K reveals slope change at approximately 775 C. From the Rietveld analysis, the oxygen vacancies are the most remarkable at the O2 (O4) sites at lower (higher) temperatures than about 800 C, which temperature is approximately comparable with that of slope change in the K. These facts mean that distribution of vacancy sites in the SLF4310 changes at approximately 775 C, accompanying no structural phase transition. The vacancy distribution change affects to the ion conductivity of the SLF4310. - Graphical abstract: Crystal structure of (Sr{sub 0.775}La{sub 0.225}){sub 4}Fe{sub 3}O{sub 10??} (SLF4310) at 1000 C. Display Omitted - Highlights: Distribution change of oxygen vacancies is appeared at approximately 775 C. The distribution change with no structure phase transition is the first observation. The vacancy distribution change affects the ion conductivity of the SLF4310.

  5. Anharmonic Potential Constants and Their Dependence Upon Bond Length

    DOE R&D Accomplishments [OSTI]

    Herschbach, D. R.; Laurie, V. W.

    1961-01-01

    Empirical study of cubic and quartic vibrational force constants for diatomic molecules shows them to be approximately exponential functions of internuclear distance. A family of curves is obtained, determined by the location of the bonded atoms in rows of the periodic table. Displacements between successive curves correspond closely to those in Badger's rule for quadratic force constants (for which the parameters are redetermined to accord with all data now available). Constants for excited electronic and ionic states appear on practically the same curves as those for the ground states. Predictions based on the diatomic correlations agree with the available cubic constants for bond stretching in polyatomic molecules, regardless of the type of bonding involved. Implications of these regularities are discussed. (auth)

  6. ESR melting under constant voltage conditions

    SciTech Connect (OSTI)

    Schlienger, M.E.

    1997-02-01

    Typical industrial ESR melting practice includes operation at a constant current. This constant current operation is achieved through the use of a power supply whose output provides this constant current characteristic. Analysis of this melting mode indicates that the ESR process under conditions of constant current is inherently unstable. Analysis also indicates that ESR melting under the condition of a constant applied voltage yields a process which is inherently stable. This paper reviews the process stability arguments for both constant current and constant voltage operation. Explanations are given as to why there is a difference between the two modes of operation. Finally, constant voltage process considerations such as melt rate control, response to electrode anomalies and impact on solidification will be discussed.

  7. Emergent cosmological constant from colliding electromagnetic waves

    SciTech Connect (OSTI)

    Halilsoy, M.; Mazharimousavi, S. Habib; Gurtug, O. E-mail: habib.mazhari@emu.edu.tr

    2014-11-01

    In this study we advocate the view that the cosmological constant is of electromagnetic (em) origin, which can be generated from the collision of em shock waves coupled with gravitational shock waves. The wave profiles that participate in the collision have different amplitudes. It is shown that, circular polarization with equal amplitude waves does not generate cosmological constant. We also prove that the generation of the cosmological constant is related to the linear polarization. The addition of cross polarization generates no cosmological constant. Depending on the value of the wave amplitudes, the generated cosmological constant can be positive or negative. We show additionally that, the collision of nonlinear em waves in a particular class of Born-Infeld theory also yields a cosmological constant.

  8. Constant voltage electro-slag remelting control

    DOE Patents [OSTI]

    Schlienger, M.E.

    1996-10-22

    A system for controlling electrode gap in an electro-slag remelt furnace has a constant regulated voltage and an electrode which is fed into the slag pool at a constant rate. The impedance of the circuit through the slag pool is directly proportional to the gap distance. Because of the constant voltage, the system current changes are inversely proportional to changes in gap. This negative feedback causes the gap to remain stable. 1 fig.

  9. Constant voltage electro-slag remelting control

    SciTech Connect (OSTI)

    Schlienger, Max E.

    1996-01-01

    A system for controlling electrode gap in an electro-slag remelt furnace has a constant regulated voltage and an eletrode which is fed into the slag pool at a constant rate. The impedance of the circuit through the slag pool is directly proportional to the gap distance. Because of the constant voltage, the system current changes are inversely proportional to changes in gap. This negative feedback causes the gap to remain stable.

  10. Constant Volume During Combustion | Department of Energy

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

    Constant Volume During Combustion Constant Volume During Combustion This presentation covers constant volume during combustion and discusses how it can alter the kinematics of piston to crankshaft travel. deer08_joniec.pdf (88.76 KB) More Documents & Publications Utilizing the Rapid Ignition Region of HCCI to Attain > 60% BTE 50% thermo-mechanical efficiency utilizing a free-piston engine in Hybrid vehicles DOE-HDBK-1018/1-93

  11. A Thomson-type mass and energy spectrometer for characterizing ion energy distributions in a coaxial plasma gun operating in a gas-puff mode

    SciTech Connect (OSTI)

    Rieker, G. B.; Poehlmann, F. R.; Cappelli, M. A.

    2013-07-15

    Measurements of ion energy distribution are performed in the accelerated plasma of a coaxial electromagnetic plasma gun operating in a gas-puff mode at relatively low discharge energy (900 J) and discharge potential (4 kV). The measurements are made using a Thomson-type mass and energy spectrometer with a gated microchannel plate and phosphor screen as the ion sensor. The parabolic ion trajectories are captured from the sensor screen with an intensified charge-coupled detector camera. The spectrometer was designed and calibrated using the Geant4 toolkit, accounting for the effects on the ion trajectories of spatial non-uniformities in the spectrometer magnetic and electric fields. Results for hydrogen gas puffs indicate the existence of a class of accelerated protons with energies well above the coaxial discharge potential (up to 24 keV). The Thomson analyzer confirms the presence of impurities of copper and iron, also of relatively high energies, which are likely erosion or sputter products from plasma-electrode interactions.

  12. Distribution of free carriers near heavily-doped epitaxial surfaces of n-type Ge(100) upon HF and HCl treatments

    SciTech Connect (OSTI)

    Park, S. J.; Bolotov, L.; Uchida, N.; Tada, T.

    2015-10-15

    Carrier distributions near n-type epitaxially-grown Ge(100) surfaces with high impurity concentrations (1 × 10{sup 20} cm{sup −3}) were studied using high resolution electron energy loss spectroscopy (HREELS) upon surface treatments in aqueous solutions of HF and HCl. After surface treatments with HCl and HF, the molecular vibration modes distinctly showed either chloride or hydride terminations of Ge surfaces with negligible oxidation. The free-carrier concentration profile was inferred from the conduction band plasmon measurements as a function of the incident electron energies employing a dielectric theory simulation with a 4-layer structure and an effective electron mass of 0.02m{sub 0}. A carrier-free layer of 40 and 24 Å were derived for HCl- and HF-treated Ge(100), respectively. The surface band bending was estimated to be 0.32 eV for HF-treated Ge. HCl-treated Ge surfaces showed a band bending of 0.91 eV attributed to the strong effect of the surface Cl-Ge dipole.

  13. Two-dimensional model of the air flow and temperature distribution in a cavity-type heat receiver of a solar stirling engine

    SciTech Connect (OSTI)

    Makhkamov, K.K.; Ingham, D.B.

    1999-11-01

    A theoretical study on the air flow and temperature in the heat receiver, affected by free convection, of a Stirling Engine for a Dish/Stirling Engine Power System is presented. The standard {kappa}-{epsilon} turbulence model for the fluid flow has been used and the boundary conditions employed were obtained using a second level mathematical model of the Stirling Engine working cycle. Physical models for the distribution of the solar insolation from the Concentrator on the bottom and side walls of the cavity-type heat receiver have been taken into account. The numerical results show that most of the heat losses in the receiver are due to re-radiation from the cavity and conduction through the walls of the cavity. It is in the region of the boundary of the input window of the heat receiver where there is a sensible reduction in the temperature in the shell of the heat exchangers and this is due to the free convection of the air. Further, the numerical results show that convective heat losses increase with decreasing tilt angle.

  14. Hydrogen, Deuterium and Tritium in Palladium: An Elastic Constants Study

    SciTech Connect (OSTI)

    Bach, H.T.; Schwarz, R.B.; Tuggle, D.G.

    2005-07-15

    We have used resonant ultrasound spectroscopy to measure the three independent elastic constants of Pd-H, Pd-D, and Pd-T single crystal at 300K as a function of hydrogen, deuterium, and tritium concentration, respectively. The addition of interstitial H (D, or T) atoms, located at (0,1/2,0) in the fcc Pd lattice, affects all three elastic constants C', C{sub 44}, and B. In the mixed ({alpha}+{beta}) phase, and with increasing H isotope, the shear modulus C' shows an abnormal softening whereas C{sub 44} and B do not. This is explained in terms of Zener-type an elastic relaxations affecting the shape of the hydride phases in the coherent({alpha}+{beta}) two-phase mixture In the single {beta}-phase, C' shows a strong isotope dependence whereas C{sub 44} and B show none. This behavior is explained in terms of differences in the excitation of optical phonons. In Pd-T, {sup 3}He is produced by the radioactive decay of tritium. We have measured in situ the swelling and the change in the elastic constants in Pd-T as a function of aging time. Aging ({sup 3}He formation) affects all three elastic constants. These measurements are being used to understand the early stages of {sup 3}H-{sup 3}He cluster formation in aged Pd-T crystal.

  15. Hydrogen, deuterium and tritium in palladium: An eleastic constants study

    SciTech Connect (OSTI)

    Bach, H. T.; Schwarz, R. B.; Tuggle, D. G.

    2004-01-01

    We have used resonant ultrasound spectroscopy to measure the three independent elastic constants of Pd-H, Pd-D, and Pd-T single crystal at 300K as a junction of hydrogen, deuterium, and tritium concentration, respectively. The addition of interstitial H (D, or T) atoms, located at (0, 1/2, 0) in the fcc Pd lattice, affects all three elastic constants C, C{sub 44}, and B. In the mixed (a+{beta}) phase, and with increasing H isotope, the shear modulus C' shows an abnormal softening whereas C{sub 44} and B do not. This is explained in terms of Zener-type anelastic relaxations affecting the shape of the hydride phases in the coherent ({alpha}+{beta}) two-phase mixture In the single {beta}-phase, C' shows a strong isotope dependence whereas C{sub 44} and B show none. This behavior is explained in terms of differences in the excitation of optical phonons. In Pd-T, {sup 3}He is produced by the radioactive decay of tritium. We have measured in situ the swelling and the change in the elastic constants in Pd-T as a function of aging time. Aging ({sup 3}He formation) affects all three elastic constants. These measurements are being used to understand the early stages of {sup 3}H-{sup 3}He clusterformation in aged Pd-T crystal.

  16. Inverse problem in anisotropic poroelasticity: Drained constants from undrained ultrasound measurements

    SciTech Connect (OSTI)

    Berryman, J.G.; Nakagawa, S.

    2009-11-20

    Poroelastic analysis has traditionally focused on the relationship between dry or drained constants which are assumed known and the saturated or undrained constants which are assumed unknown. However, there are many applications in this field of study for which the main measurements can only be made on the saturated/undrained system, and then it is uncertain what the eects of the uids were on the system, since the drained constants remain a mystery. The work presented here shows how to deduce drained constants from undrained constants for anisotropic systems having symmetries ranging from isotropic to orthotropic. Laboratory ultrasound data are then inverted for the drained constants in three granular packings: one of glass beads, and two others for distinct types of more or less angular sand grain packings. Experiments were performed under uniaxial stress, which resulted in hexagonal (transversely isotropic) symmetry of the poroelastic response. One important conclusion from the general analysis is that the drained constants are uniquely related to the undrained constants, assuming that porosity, grain bulk modulus, and pore uid bulk modulus are already known. Since the resulting system of equations for all the drained constants is linear, measurement error in undrained constants also propagates linearly into the computed drained constants.

  17. The vibrational dependence of dissociative recombination: Rate constants for N{sub 2}{sup +}

    SciTech Connect (OSTI)

    Guberman, Steven L.

    2014-11-28

    Dissociative recombination rate constants are reported with electron temperature dependent uncertainties for the lowest 5 vibrational levels of the N{sub 2}{sup +} ground state. The rate constants are determined from ab initio calculations of potential curves, electronic widths, quantum defects, and cross sections. At 100 K electron temperature, the rate constants overlap with the exception of the third vibrational level. At and above 300 K, the rate constants for excited vibrational levels are significantly smaller than that for the ground level. It is shown that any experimentally determined total rate constant at 300 K electron temperature that is smaller than 2.0 10{sup ?7} cm{sup 3}/s is likely to be for ions that have a substantially excited vibrational population. Using the vibrational level specific rate constants, the total rate constant is in very good agreement with that for an excited vibrational distribution found in a storage ring experiment. It is also shown that a prior analysis of a laser induced fluorescence experiment is quantitatively flawed due to the need to account for reactions with unknown rate constants. Two prior calculations of the dissociative recombination rate constant are shown to be inconsistent with the cross sections upon which they are based. The rate constants calculated here contribute to the resolution of a 30 year old disagreement between modeled and observed N{sub 2}{sup +} ionospheric densities.

  18. A nuclear data approach for the Hubble constant measurements

    SciTech Connect (OSTI)

    Pritychenko, B.

    2015-06-09

    An extraordinary number of Hubble constant measurements challenges physicists with selection of the best numerical value. The standard U.S. Nuclear Data Program (USNDP) codes and procedures have been applied to resolve this issue. The nuclear data approach has produced the most probable or recommended Hubble constant value of 67.00(770) (km/sec)/Mpc. This recommended value is based on the last 25 years of experimental research and includes contributions from different types of measurements. The present result implies (14.6±1.7) x 109 years as a rough estimate for the age of the Universe. The complete list of recommended results is given and possible implications are discussed.

  19. Binary Solid Propellants for Constant Momentum Missions

    SciTech Connect (OSTI)

    Pakhomov, Andrew V.; Mahaffy, Kevin E.

    2008-04-28

    A constant momentum mission is achieved when the speed of the vehicle in the inertial frame of reference is equal to the speed of exhaust relative to the vehicle. Due to 100% propulsive efficiency such missions are superior to traditional constant specific impulse missions. A new class of solid binary propellants for constant momentum missions is under development. A typical propellant column is prepared as a solid solution of two components, with composition gradually changing from 100% of a propellant of high coupling coefficient (C{sub m}) to one which has high specific impulse (I{sub sp}). The high coupling component is ablated first, gradually giving way to the high I{sub sp} component, as the vehicle accelerates. This study opens new opportunities for further design of complex propellants for laser propulsion, providing variable C{sub m} and I{sub sp} during missions.

  20. Microfabricated microengine with constant rotation rate

    DOE Patents [OSTI]

    Romero, Louis A. (Albuquerque, NM); Dickey, Fred M. (Albuquerque, NM)

    1999-01-01

    A microengine uses two synchronized linear actuators as a power source and converts oscillatory motion from the actuators into constant rotational motion via direct linkage connection to an output gear or wheel. The microengine provides output in the form of a continuously rotating output gear that is capable of delivering drive torque at a constant rotation to a micromechanism. The output gear can have gear teeth on its outer perimeter for directly contacting a micromechanism requiring mechanical power. The gear is retained by a retaining means which allows said gear to rotate freely. The microengine is microfabricated of polysilicon on one wafer using surface micromachining batch fabrication.

  1. Our Universe from the cosmological constant

    SciTech Connect (OSTI)

    Barrau, Aurlien; Linsefors, Linda E-mail: linda.linsefors@lpsc.in2p3.fr

    2014-12-01

    The issue of the origin of the Universe and of its contents is addressed in the framework of bouncing cosmologies, as described for example by loop quantum gravity. If the current acceleration is due to a true cosmological constant, this constant is naturally conserved through the bounce and the Universe should also be in a (contracting) de Sitter phase in the remote past. We investigate here the possibility that the de Sitter temperature in the contracting branch fills the Universe with radiation that causes the bounce and the subsequent inflation and reheating. We also consider the possibility that this gives rise to a cyclic model of the Universe and suggest some possible tests.

  2. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, O.A.

    1988-07-13

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90/degree/ intervals with opposing electrodes maintained at the same potential. 12 figs., 3 tabs.

  3. Wall of fundamental constants (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Wall of fundamental constants Citation Details In-Document Search Title: Wall of fundamental constants Authors: Olive, Keith A. ; Peloso, Marco ; Uzan, Jean-Philippe Publication ...

  4. Measuring Advances in HVAC Distribution System Design

    SciTech Connect (OSTI)

    Franconi, E.

    1998-05-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HV AC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  5. Variable energy constant current accelerator structure

    DOE Patents [OSTI]

    Anderson, Oscar A.

    1990-01-01

    A variable energy, constant current ion beam accelerator structure is disclosed comprising an ion source capable of providing the desired ions, a pre-accelerator for establishing an initial energy level, a matching/pumping module having means for focusing means for maintaining the beam current, and at least one main accelerator module for continuing beam focus, with means capable of variably imparting acceleration to the beam so that a constant beam output current is maintained independent of the variable output energy. In a preferred embodiment, quadrupole electrodes are provided in both the matching/pumping module and the one or more accelerator modules, and are formed using four opposing cylinder electrodes which extend parallel to the beam axis and are spaced around the beam at 90.degree. intervals with opposing electrodes maintained at the same potential. Adjacent cylinder electrodes of the quadrupole structure are maintained at different potentials to thereby reshape the cross section of the charged particle beam to an ellipse in cross section at the mid point along each quadrupole electrode unit in the accelerator modules. The beam is maintained in focus by alternating the major axis of the ellipse along the x and y axis respectively at adjacent quadrupoles. In another embodiment, electrostatic ring electrodes may be utilized instead of the quadrupole electrodes.

  6. Predicting the cosmological constant from the causal entropic principle

    SciTech Connect (OSTI)

    Bousso, Raphael; Harnik, Roni; Kribs, Graham D.; Perez, Gilad

    2007-08-15

    We compute the expected value of the cosmological constant in our universe from the causal entropic principle. Since observers must obey the laws of thermodynamics and causality, the principle asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approach - weighting by the number of 'observers per baryon' - is less well-defined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.

  7. Predicting the Cosmological Constant from the Causal Entropic Principle

    SciTech Connect (OSTI)

    Bousso, Raphael; Bousso, Raphael; Harnik, Roni; Kribs, Graham D.; Perez, Gilad

    2007-05-01

    We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, the principle asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approach-weighting by the number of"observers per baryon" -- is less well-defined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.

  8. Predicting the Cosmological Constant from the CausalEntropic Principle

    SciTech Connect (OSTI)

    Bousso, Raphael; Harnik, Roni; Kribs, Graham D.; Perez, Gilad

    2007-02-20

    We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, it asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approach--weighting by the number of ''observers per baryon''--is less well-defined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.

  9. Constant pressure high throughput membrane permeation testing...

    Office of Scientific and Technical Information (OSTI)

    Authors: Albenze, Erik J. ; Hopkinson, David P. ; Luebke, David R. Publication Date: 2014-09-02 OSTI Identifier: 1156820 Report Number(s): 8,821,614 13629,733 Resource Type: ...

  10. Gravitational collapse and the cosmological constant

    SciTech Connect (OSTI)

    Deshingkar, S. S.; Jhingan, S.; Chamorro, A.; Joshi, P. S.

    2001-06-15

    We consider here the effects of a nonvanishing cosmological term on the final fate of a spherical inhomogeneous collapsing dust cloud. It is shown that, depending on the nature of the initial data from which the collapse evolves, and for a positive value of the cosmological constant, we can have a globally regular evolution where a bounce develops within the cloud. We characterize precisely the initial data causing such a bounce in terms of the initial density and velocity profiles for the collapsing cloud. In the cases otherwise, the result of collapse is either the formation of a black hole or a naked singularity resulting as the end state of collapse. We also show here that a positive cosmological term can cover a part of the singularity spectrum which is visible in the corresponding dust collapse models for the same initial data.

  11. Constant field gradient planar coupled cavity structure

    DOE Patents [OSTI]

    Kang, Y.W.; Kustom, R.L.

    1999-07-27

    A cavity structure is disclosed having at least two opposing planar housing members spaced apart to accommodate the passage of a particle beam through the structure between the members. Each of the housing members have a plurality of serially aligned hollows defined therein, and also passages, formed in the members, which interconnect serially adjacent hollows to provide communication between the hollows. The opposing planar housing members are spaced and aligned such that the hollows in one member cooperate with corresponding hollows in the other member to form a plurality of resonant cavities aligned along the particle beam within the cavity structure. To facilitate the obtaining of a constant field gradient within the cavity structure, the passages are configured so as to be incrementally narrower in the direction of travel of the particle beam. In addition, the spacing distance between the opposing housing members is configured to be incrementally smaller in the direction of travel of the beam. 16 figs.

  12. On the local variation of the Hubble constant

    SciTech Connect (OSTI)

    Odderskov, Io; Hannestad, Steen [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Haugblle, Troels, E-mail: isho07@phys.au.dk, E-mail: sth@phys.au.dk, E-mail: troels.haugboelle@snm.ku.dk [Centre for Star and Planet Formation, Natural History Museum of Denmark and Niels Bohr Institute University of Copenhagen, DK-1350 Copenhagen (Denmark)

    2014-10-01

    We have carefully studied how local measurements of the Hubble constant, H{sub 0}, can be influenced by a variety of different parameters related to survey depth, size, and fraction of the sky observed, as well as observer position in space. Our study is based on N-body simulations of structure in the standard ?CDM model and our conclusion is that the expected variance in measurements of H{sub 0} is far too small to explain the current discrepancy between the low value of H{sub 0} inferred from measurements of the cosmic microwave background (CMB) by the Planck collaboration and the value measured directly in the local universe by use of Type Ia supernovae. This conclusion is very robust and does not change with different assumptions about effective sky coverage and depth of the survey or observer position in space.

  13. Identification of a distinct type IV collagen. alpha. chain with restricted kidney distribution and assignment of its gene to the locus of X chromosome-linked Alport syndrome

    SciTech Connect (OSTI)

    Hostikka, S.L.; Hoeyhtyae, M.; Tryggvason, K. ); Eddy, R.L.; Byers, M.G.; Shows, T.B. )

    1990-02-01

    The authors have identified and extensively characterized a type IV collagen {alpha} chain, referred to as {alpha}5(IV). Four overlapping cDNA clones isolated contain an open reading frame for 543 amino acid residues of the carboxyl-terminal end of a collagenous domain, a 229-residue carboxyl-terminal noncollagenous domain, and 1201 base pairs coding for a 3{prime} untranslated region. The collagenous Gly-Xaa-Yaa repeat sequence has five imperfections that coincide with those in the corresponding region of the {alpha}1(IV) chain. The noncollagenous domain has 12 conserved cysteine residues and 83% and 63% sequence identity with the noncollagenous domains of the {alpha}1(IV) and {alpha}2(IV) chains, respectively. The {alpha}5(IV) chain has less sequence identity with the putative bovine {alpha}3(IV) and {alpha}4(IV) chains. Antiserum against an {alpha}5(IV) synthetic peptide stained a polypeptide chain of about 185 kDa by immunoblot analysis and immunolocalization of the chain in human kidney was almost completely restricted to the glomerulus. The gene was assigned to the Xq22 locus by somatic cell hybrids and in situ hybridization. This may be identical or close to the locus of the X chromosome-linked Alport syndrome that is believed to be a type IV collagen disease.

  14. Determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer quantum dots via spectral analysis of optical signature of the Aharanov-Bohm excitons

    SciTech Connect (OSTI)

    Ji, Haojie; Dhomkar, Siddharth; Roy, Bidisha; Kuskovsky, Igor L.; Shuvayev, Vladimir; Deligiannakis, Vasilios; Tamargo, Maria C.; Ludwig, Jonathan; Smirnov, Dmitry; Wang, Alice

    2014-10-28

    For submonolayer quantum dot (QD) based photonic devices, size and density of QDs are critical parameters, the probing of which requires indirect methods. We report the determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer QDs, based on spectral analysis of the optical signature of Aharanov-Bohm (AB) excitons, complemented by photoluminescence studies, secondary-ion mass spectroscopy, and numerical calculations. Numerical calculations are employed to determine the AB transition magnetic field as a function of the type-II QD radius. The study of four samples grown with different tellurium fluxes shows that the lateral size of QDs increases by just 50%, even though tellurium concentration increases 25-fold. Detailed spectral analysis of the emission of the AB exciton shows that the QD radii take on only certain values due to vertical correlation and the stacked nature of the QDs.

  15. Variation of stability constants of thorium citrate complexes and of thorium hydrolysis constants with ionic strength

    SciTech Connect (OSTI)

    Choppin, G.R.; Erten, H.N.; Xia, Y.X.

    1995-09-01

    Citrate is among the organic anions that are expected to be present in the wastes planned for deposition in the Waste Isolation Pilot Plant repository. In this study, a solvent extraction method has been used to measure the stability constants of Thorium(IV)[Th(IV)] with citrate anions in aqueous solutions with (a) NaClO{sub 4} and (b) NaCl as the background electrolytes. The ionic strengths were varied up to 5 m (NaCl) and 14 m (NaClO{sub 4}). The data from the NaClO{sub 4} solutions at varying pH values were used to calculate the hydrolysis constants for formation of Th(OH){sup 3+} at the different ionic strengths.

  16. Final Technical Report for Interagency Agreement No. DE-SC0005453 “Characterizing Aerosol Distributions, Types, and Optical and Microphysical Properties using the NASA Airborne High Spectral Resolution Lidar (HSRL) and the Research Scanning Polarimeter (RSP)”

    SciTech Connect (OSTI)

    Hostetler, Chris; Ferrare, Richard

    2015-01-13

    Measurements of the vertical profile of atmospheric aerosols and aerosol optical and microphysical characteristics are required to: 1) determine aerosol direct and indirect radiative forcing, 2) compute radiative flux and heating rate profiles, 3) assess model simulations of aerosol distributions and types, and 4) establish the ability of surface and space-based remote sensors to measure the indirect effect. Consequently the ASR program calls for a combination of remote sensing and in situ measurements to determine aerosol properties and aerosol influences on clouds and radiation. As part of our previous DOE ASP project, we deployed the NASA Langley airborne High Spectral Resolution Lidar (HSRL) on the NASA B200 King Air aircraft during major field experiments in 2006 (MILAGRO and MaxTEX), 2007 (CHAPS), 2009 (RACORO), and 2010 (CalNex and CARES). The HSRL provided measurements of aerosol extinction (532 nm), backscatter (532 and 1064 nm), and depolarization (532 and 1064 nm). These measurements were typically made in close temporal and spatial coincidence with measurements made from DOE-funded and other participating aircraft and ground sites. On the RACORO, CARES, and CalNEX missions, we also deployed the NASA Goddard Institute for Space Studies (GISS) Research Scanning Polarimeter (RSP). RSP provided intensity and degree of linear polarization over a broad spectral and angular range enabling column-average retrievals of aerosol optical and microphysical properties. Under this project, we analyzed observations and model results from RACORO, CARES, and CalNex and accomplished the following objectives. 1. Identified aerosol types, characterize the vertical distribution of the aerosol types, and partition aerosol optical depth by type, for CARES and CalNex using HSRL data as we have done for previous missions. 2. Investigated aerosol microphysical and macrophysical properties using the RSP. 3. Used the aerosol backscatter and extinction profiles measured by the HSRL

  17. FRIB cryogenic distribution system

    SciTech Connect (OSTI)

    Ganni, Venkatarao; Dixon, Kelly D.; Laverdure, Nathaniel A.; Knudsen, Peter N.; Arenius, Dana M.; Barrios, Matthew N.; Jones, S.; Johnson, M.; Casagrande, Fabio

    2014-01-01

    The Michigan State University Facility for Rare Isotope Beams (MSU-FRIB) helium distribution system has been revised to include bayonet/warm valve type disconnects between each cryomodule and the transfer line distribution system, similar to the Thomas Jefferson National Accelerator Facility (JLab) and the Spallation Neutron Source (SNS) cryogenic distribution systems. The heat loads at various temperature levels and some of the features in the design of the distribution system are outlined. The present status, the plans for fabrication, and the procurement approach for the helium distribution system are also included.

  18. EIS Distribution

    Broader source: Energy.gov [DOE]

    This DOE guidance presents a series of recommendations related to the EIS distribution process, which includes creating and updating a distribution list, distributing an EIS, and filing an EIS with the EPA.

  19. Observational constraints on holographic dark energy with varying gravitational constant

    SciTech Connect (OSTI)

    Lu, Jianbo; Xu, Lixin; Saridakis, Emmanuel N.; Setare, M.R. E-mail: msaridak@phys.uoa.gr E-mail: lxxu@dlut.edu.cn

    2010-03-01

    We use observational data from Type Ia Supernovae (SN), Baryon Acoustic Oscillations (BAO), Cosmic Microwave Background (CMB) and observational Hubble data (OHD), and the Markov Chain Monte Carlo (MCMC) method, to constrain the cosmological scenario of holographic dark energy with varying gravitational constant. We consider both flat and non-flat background geometry, and we present the corresponding constraints and contour-plots of the model parameters. We conclude that the scenario is compatible with observations. In 1? we find ?{sub ?0} = 0.72{sup +0.03}{sub ?0.03}, ?{sub k0} = ?0.0013{sup +0.0130}{sub ?0.0040}, c = 0.80{sup +0.19}{sub ?0.14} and ?{sub G}?G'/G = ?0.0025{sup +0.0080}{sub ?0.0050}, while for the present value of the dark energy equation-of-state parameter we obtain w{sub 0} = ?1.04{sup +0.15}{sub ?0.20}.

  20. High Dielectric Constant Capacitors for Power Electronic Systems |

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

    Department of Energy 09 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. ape_05_balachandran.pdf (912.46 KB) More Documents & Publications High Dialectric Constant Capacitors for Power Electronic Systems High Dialectric Constant Capacitors for Power Electronic Systems High Dialectric

  1. Methodology for extracting local constants from petroleum cracking flows

    DOE Patents [OSTI]

    Chang, Shen-Lin; Lottes, Steven A.; Zhou, Chenn Q.

    2000-01-01

    A methodology provides for the extraction of local chemical kinetic model constants for use in a reacting flow computational fluid dynamics (CFD) computer code with chemical kinetic computations to optimize the operating conditions or design of the system, including retrofit design improvements to existing systems. The coupled CFD and kinetic computer code are used in combination with data obtained from a matrix of experimental tests to extract the kinetic constants. Local fluid dynamic effects are implicitly included in the extracted local kinetic constants for each particular application system to which the methodology is applied. The extracted local kinetic model constants work well over a fairly broad range of operating conditions for specific and complex reaction sets in specific and complex reactor systems. While disclosed in terms of use in a Fluid Catalytic Cracking (FCC) riser, the inventive methodology has application in virtually any reaction set to extract constants for any particular application and reaction set formulation. The methodology includes the step of: (1) selecting the test data sets for various conditions; (2) establishing the general trend of the parametric effect on the measured product yields; (3) calculating product yields for the selected test conditions using coupled computational fluid dynamics and chemical kinetics; (4) adjusting the local kinetic constants to match calculated product yields with experimental data; and (5) validating the determined set of local kinetic constants by comparing the calculated results with experimental data from additional test runs at different operating conditions.

  2. Viscous gravitational aether and the cosmological constant problem

    SciTech Connect (OSTI)

    Kuang, Xiaomei; Ling, Yi E-mail: yling@ncu.edu.cn

    2009-10-01

    Recently a notion of gravitational aether is advocated to solve the cosmological constant problem. Through the modification of the source of gravity one finds that the effective Newton's constant is source dependent so as to provide a simple but consistent way to decouple gravity from the vacuum energy. However, in the original paper the ratio of the effective Newton's constants for pressureless dust and radiation has an upper bound which is 0.75. In this paper we propose a scheme to loose this bound by introducing a bulk viscosity for the gravitational aether, and expect this improvement will provide more space for matching predictions from this theoretical programm with observational constraints.

  3. Experimental determination of the effective strong coupling constant

    SciTech Connect (OSTI)

    Alexandre Deur; Volker Burkert; Jian-Ping Chen; Wolfgang Korsch

    2007-07-01

    We extract an effective strong coupling constant from low Q{sup 2} data on the Bjorken sum. Using sum rules, we establish its Q{sup 2}-behavior over the complete Q{sup 2}-range. The result is compared to effective coupling constants extracted from different processes and to calculations based on Schwinger-Dyson equations, hadron spectroscopy or lattice QCD. Although the connection between the experimentally extracted effective coupling constant and the calculations is not clear, the results agree surprisingly well.

  4. CEPHEID CALIBRATIONS OF MODERN TYPE Ia SUPERNOVAE: IMPLICATIONS...

    Office of Scientific and Technical Information (OSTI)

    CEPHEID CALIBRATIONS OF MODERN TYPE Ia SUPERNOVAE: IMPLICATIONS FOR THE HUBBLE CONSTANT ... Country of Publication: United States Language: English Subject: 79 ASTROPHYSICS, ...

  5. Distributed Generation

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

    and regulations such as IEEE (Institute of Electrical and Electronics Engineers) 1547 have come a long way in addressing interconnection standards for distributed generation, ...

  6. Distribution Workshop

    Broader source: Energy.gov [DOE]

    On September 24-26, 2012, the GTT presented a workshop on grid integration on the distribution system at the Sheraton Crystal City near Washington, DC.

  7. The sixteen channel CAMAC constant fraction discriminator for APEX

    SciTech Connect (OSTI)

    Maier, M.R. ); Robertson, M. ); Wolfs, F.L.H.; Perera, P.A.A. . Nuclear Structure Research Lab.)

    1991-11-01

    We report on the construction and the performance of a sixteen channel constant fraction discriminator (CFD) for the Atlas Positron Experiment (APEX). We have used an integrated circuit (IC), recently introduced commercially, which contains all the electronic building blocks needed to construct a CFD. We have placed 16 channels of CFD into a CAMAC module. An important feature is the time to charge converter (TQC) that we have included for every CFD channel. Its calibration constant is controlled via CAMAC. The TQC allows the use charge sensitive analog to digital converters (QDC) for timing measurements. Results for CFD walk, resolution and crosstalk as well as for TQC linearity will be presented.

  8. Temperature and moisture dependence of dielectric constant for silica aerogels

    SciTech Connect (OSTI)

    Hrubesh, L.H., LLNL

    1997-03-01

    The dielectric constants of silica aerogels are among the lowest measured for any solid material. The silica aerogels also exhibit low thermal expansion and are thermally stable to temperatures exceeding 500{degrees}C. However, due to the open porosity and large surface areas for aerogels, their dielectric constants are strongly affected by moisture and temperature. This paper presents data for the dielectric constants of silica aerogels as a function of moisture content at 25{degrees}C, and as a function of temperature, for temperatures in the range from 25{degrees}C to 450{degrees}C. Dielectric constant data are also given for silica aerogels that are heat treated in dry nitrogen at 500{degrees}C, then cooled to 25{degrees}C for measurements in dry air. All measurements are made on bulk aerogel spheres at 22GHz microwave frequency, using a cavity perturbation method. The results of the dependence found here for bulk materials can be inferred to apply also to thin films of silica aerogels having similar nano-structures and densities.

  9. ITP Industrial Distributed Energy: Distributed Energy Program...

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

    ITP Industrial Distributed Energy: Distributed Energy Program Project Profile: Verizon Central Office Building ITP Industrial Distributed Energy: Distributed Energy Program Project ...

  10. Property:Distributed Generation System Heating-Cooling Application...

    Open Energy Info (EERE)

    This is a property of type Page. Pages using the property "Distributed Generation System Heating-Cooling Application" Showing 21 pages using this property. D Distributed...

  11. Property:Distributed Generation Function | Open Energy Information

    Open Energy Info (EERE)

    Function Jump to: navigation, search Property Name Distributed Generation Function Property Type Page Description A description of the function(s) for which the Distributed...

  12. Is there further evidence for spatial variation of fundamental constants?

    SciTech Connect (OSTI)

    Berengut, J. C.; Flambaum, V. V.; King, J. A.; Curran, S. J.; Webb, J. K.

    2011-06-15

    Indications of spatial variation of the fine-structure constant, {alpha}, based on study of quasar absorption systems have recently been reported [J. K. Webb, J. A. King, M. T. Murphy, V. V. Flambaum, R. F. Carswell, and M. B. Bainbridge, arXiv:1008.3907.]. The physics that causes this {alpha}-variation should have other observable manifestations, and this motivates us to look for complementary astrophysical effects. In this paper we propose a method to test whether spatial variation of fundamental constants existed during the epoch of big bang nucleosynthesis and study existing measurements of deuterium abundance for a signal. We also examine existing quasar absorption spectra data that are sensitive to variation of the electron-to-proton mass ratio {mu} and x={alpha}{sup 2{mu}}g{sub p} for spatial variation.

  13. Defect density and dielectric constant in perovskite solar cells

    SciTech Connect (OSTI)

    Samiee, Mehran; Konduri, Siva; Abbas, Hisham A.; Joshi, Pranav; Zhang, Liang; Dalal, Vikram; Ganapathy, Balaji; Kottokkaran, Ranjith; Noack, Max; Kitahara, Andrew

    2014-10-13

    We report on measurement of dielectric constant, mid-gap defect density, Urbach energy of tail states in CH{sub 3}NH{sub 3}PbI{sub x}Cl{sub 1?x} perovskite solar cells. Midgap defect densities were estimated by measuring capacitance vs. frequency at different temperatures and show two peaks, one at 0.66?eV below the conduction band and one at 0.24?eV below the conduction band. The attempt to escape frequency is in the range of 2??10{sup 11}/s. Quantum efficiency data indicate a bandgap of 1.58?eV. Urbach energies of valence and conduction band are estimated to be ?16 and ?18?meV. Measurement of saturation capacitance indicates that the relative dielectric constant is ?18.

  14. New process to avoid emissions: Constant pressure in coke ovens

    SciTech Connect (OSTI)

    Giertz, J.; Huhn, F.; Hofherr, K.

    1995-12-01

    A chamber pressure regulation (PROven), especially effective in regard to emission control problems of coke ovens is introduced for the first time. Because of the partial vacuum in the collecting main system, it is possible to keep the oven`s raw gas pressure constant on a low level over the full coking time. The individual pressure control for each chamber is assured directly as a function of the oven pressure by an immersion system controlling the flow resistance of the collecting main valve. The latter is a fixed-position design (system name ``FixCup``). By doing away with the interdependence of collecting main pressure and chamber pressure, a parameter seen as a coking constant could not be made variable. This opens a new way to reduce coke oven emissions and simultaneously to prevent the ovens from damage caused by air ingress into the oven.

  15. Mega-masers, Dark Energy and the Hubble Constant

    SciTech Connect (OSTI)

    Lo, Fred K. Y.

    2007-10-15

    Powerful water maser emission (water mega-masers) can be found in accretion disks in the nuclei of some galaxies. Besides providing a measure of the mass at the nucleus, such mega-masers can be used to determine the distance to the host galaxy, based on a kinematic model. We will explain the importance of determining the Hubble Constant to high accuracy for constraining the equation of state of Dark Energy and describe the Mega-maser Cosmology Project that has the goal of determining the Hubble Constant to better than 3%. Time permitting, we will also present the scientific capabilities of the current and future NRAO facilities: ALMA, EVLA, VLBA and GBT, for addressing key astrophysical problems

  16. Apparatus producing constant cable tension for intermittent demand

    DOE Patents [OSTI]

    Lauritzen, Ted

    1985-01-01

    The disclosed apparatus produces constant tension in superconducting electrical cable, or some other strand, under conditions of intermittent demand, as the cable is unreeled from a reel or reeled thereon. The apparatus comprises a pivotally supported swing frame on which the reel is rotatably supported, a rotary motor, a drive train connected between the motor and the reel and including an electrically controllable variable torque slip clutch, a servo transducer connected to the swing frame for producing servo input signals corresponding to the position thereof, a servo control system connected between the transducer and the clutch for regulating the torque transmitted by the clutch to maintain the swing frame in a predetermined position, at least one air cylinder connected to the swing frame for counteracting the tension in the cable, and pressure regulating means for supplying a constant air pressure to the cylinder to establish the constant tension in the cable, the servo system and the clutch being effective to produce torque on the reel in an amount sufficient to provide tension in the cable corresponding to the constant force exerted by the air cylinder. The drive train also preferably includes a fail-safe brake operable to its released position by electrical power in common with the servo system, for preventing rotation of the reel if there is a power failure. A shock absorber and biasing springs may also be connected to the swing frame, such springs biasing the frame toward its predetermined position. The tension in the cable may be measured by force measuring devices engageable with the bearings for the reel shaft, such bearings being supported for slight lateral movement. The reel shaft is driven by a Shmidt coupler which accommodates such movement.

  17. Turbine blade having a constant thickness airfoil skin

    DOE Patents [OSTI]

    Marra, John J

    2012-10-23

    A turbine blade is provided for a gas turbine comprising: a support structure comprising a base defining a root of the blade and a framework extending radially outwardly from the base, and an outer skin coupled to the support structure framework. The skin has a generally constant thickness along substantially the entire radial extent thereof. The framework and the skin define an airfoil of the blade.

  18. Apparatus producing constant cable tension for intermittent demand

    DOE Patents [OSTI]

    Lauritzen, T.

    1984-05-23

    This invention relates to apparatus for producing constant tension in cable or the like when it is unreeled and reeled from a drum or spool under conditions of intermittent demand. The invention is particularly applicable to the handling of superconductive cable, but the invention is also applicable to the unreeling and reeling of other strands, such as electrical cable, wire, cord, other cables, fish line, wrapping paper and numerous other materials.

  19. Electronic transport in two-dimensional high dielectric constant nanosystems

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

    Ortuño, M.; Somoza, A. M.; Vinokur, V. M.; Baturina, T. I.

    2015-04-10

    There has been remarkable recent progress in engineering high-dielectric constant two dimensional (2D) materials, which are being actively pursued for applications in nanoelectronics in capacitor and memory devices, energy storage, and high-frequency modulation in communication devices. Yet many of the unique properties of these systems are poorly understood and remain unexplored. Here we report a numerical study of hopping conductivity of the lateral network of capacitors, which models two-dimensional insulators, and demonstrate that 2D long-range Coulomb interactions lead to peculiar size effects. We find that the characteristic energy governing electronic transport scales logarithmically with either system size or electrostatic screeningmore » length depending on which one is shorter. Our results are relevant well beyond their immediate context, explaining, for example, recent experimental observations of logarithmic size dependence of electric conductivity of thin superconducting films in the critical vicinity of superconductor-insulator transition where a giant dielectric constant develops. Our findings mark a radical departure from the orthodox view of conductivity in 2D systems as a local characteristic of materials and establish its macroscopic global character as a generic property of high-dielectric constant 2D nanomaterials.« less

  20. Electronic transport in two-dimensional high dielectric constant nanosystems

    SciTech Connect (OSTI)

    Ortuño, M.; Somoza, A. M.; Vinokur, V. M.; Baturina, T. I.

    2015-04-10

    There has been remarkable recent progress in engineering high-dielectric constant two dimensional (2D) materials, which are being actively pursued for applications in nanoelectronics in capacitor and memory devices, energy storage, and high-frequency modulation in communication devices. Yet many of the unique properties of these systems are poorly understood and remain unexplored. Here we report a numerical study of hopping conductivity of the lateral network of capacitors, which models two-dimensional insulators, and demonstrate that 2D long-range Coulomb interactions lead to peculiar size effects. We find that the characteristic energy governing electronic transport scales logarithmically with either system size or electrostatic screening length depending on which one is shorter. Our results are relevant well beyond their immediate context, explaining, for example, recent experimental observations of logarithmic size dependence of electric conductivity of thin superconducting films in the critical vicinity of superconductor-insulator transition where a giant dielectric constant develops. Our findings mark a radical departure from the orthodox view of conductivity in 2D systems as a local characteristic of materials and establish its macroscopic global character as a generic property of high-dielectric constant 2D nanomaterials.

  1. THE INTERIOR STRUCTURE CONSTANTS AS AN AGE DIAGNOSTIC FOR LOW-MASS, PRE-MAIN-SEQUENCE DETACHED ECLIPSING BINARY STARS

    SciTech Connect (OSTI)

    Feiden, Gregory A.; Dotter, Aaron E-mail: aaron.dotter@gmail.com

    2013-03-10

    We propose a novel method for determining the ages of low-mass, pre-main-sequence stellar systems using the apsidal motion of low-mass detached eclipsing binaries. The apsidal motion of a binary system with an eccentric orbit provides information regarding the interior structure constants of the individual stars. These constants are related to the normalized stellar interior density distribution and can be extracted from the predictions of stellar evolution models. We demonstrate that low-mass, pre-main-sequence stars undergoing radiative core contraction display rapidly changing interior structure constants (greater than 5% per 10 Myr) that, when combined with observational determinations of the interior structure constants (with 5%-10% precision), allow for a robust age estimate. This age estimate, unlike those based on surface quantities, is largely insensitive to the surface layer where effects of magnetic activity are likely to be most pronounced. On the main sequence, where age sensitivity is minimal, the interior structure constants provide a valuable test of the physics used in stellar structure models of low-mass stars. There are currently no known systems where this technique is applicable. Nevertheless, the emphasis on time domain astronomy with current missions, such as Kepler, and future missions, such as LSST, has the potential to discover systems where the proposed method will be observationally feasible.

  2. Specificity and completion time distributions of biochemical...

    Office of Scientific and Technical Information (OSTI)

    Resource Type: Journal Article Resource Relation: Journal Name: Journal of Chemical Physics ... Language: English Subject: 37; ANALYTICAL SOLUTION; DETECTION; DISTRIBUTION; DNA ...

  3. Award Types

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

    Awards Team (505) 667-7824 Email Types of Awards The Awards Office, sponsored by the Technology Transfer Division and the Science and Technology Base Program Office, coordinates...

  4. Constant time worker thread allocation via configuration caching...

    Office of Scientific and Technical Information (OSTI)

    Type: Patent Research Org: International Business Machine Corporation, Armonk, NY (United States) Sponsoring Org: USDOE Country of Publication: United States Language: English

  5. Distributed Generation

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

    Untapped Value of Backup Generation While new guidelines and regulations such as IEEE (Institute of Electrical and Electronics Engineers) 1547 have come a long way in addressing interconnection standards for distributed generation, utilities have largely overlooked the untapped potential of these resources. Under certain conditions, these units (primarily backup generators) represent a significant source of power that can deliver utility services at lower costs than traditional centralized

  6. Distribution Category:

    Office of Legacy Management (LM)

    - Distribution Category: Remedial Action and Decommissioning Program (UC-70A) DOE/EV-0005/48 ANL-OHS/HP-84-104 ARGONNE NATIONAL LABORATORY 9700 South Cass Avenue Argonne, Illinois 60439 FORMERLY UTILIZED MXD/AEC SITES REMEDIAL ACTION PROGRAM RADIOLOGICAL SURVEY OF THE HARSHAW CHEMICAL COMPANY CLEVELAND. OHIO Prepared by R. A. Wynveen Associate Division Director, OHS W. H. Smith Senior Health Physicist C. M. Sholeen Health Physicist A. L. Justus Health Physicist K. F. Flynn Health Physicist

  7. Predicting Stability Constants for Uranyl Complexes Using Density Functional Theory

    SciTech Connect (OSTI)

    Vukovic, Sinisa; Hay, Benjamin P.; Bryantsev, Vyacheslav S.

    2015-04-02

    The ability to predict the equilibrium constants for the formation of 1:1 uranyl:ligand complexes (log K1 values) provides the essential foundation for the rational design of ligands with enhanced uranyl affinity and selectivity. We also use density functional theory (B3LYP) and the IEFPCM continuum solvation model to compute aqueous stability constants for UO22+ complexes with 18 donor ligands. Theoretical calculations permit reasonably good estimates of relative binding strengths, while the absolute log K1 values are significantly overestimated. Accurate predictions of the absolute log K1 values (root mean square deviation from experiment < 1.0 for log K1 values ranging from 0 to 16.8) can be obtained by fitting the experimental data for two groups of mono and divalent negative oxygen donor ligands. The utility of correlations is demonstrated for amidoxime and imide dioxime ligands, providing a useful means of screening for new ligands with strong chelate capability to uranyl.

  8. Predicting Stability Constants for Uranyl Complexes Using Density Functional Theory

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

    Vukovic, Sinisa; Hay, Benjamin P.; Bryantsev, Vyacheslav S.

    2015-04-02

    The ability to predict the equilibrium constants for the formation of 1:1 uranyl:ligand complexes (log K1 values) provides the essential foundation for the rational design of ligands with enhanced uranyl affinity and selectivity. We also use density functional theory (B3LYP) and the IEFPCM continuum solvation model to compute aqueous stability constants for UO22+ complexes with 18 donor ligands. Theoretical calculations permit reasonably good estimates of relative binding strengths, while the absolute log K1 values are significantly overestimated. Accurate predictions of the absolute log K1 values (root mean square deviation from experiment < 1.0 for log K1 values ranging from 0more » to 16.8) can be obtained by fitting the experimental data for two groups of mono and divalent negative oxygen donor ligands. The utility of correlations is demonstrated for amidoxime and imide dioxime ligands, providing a useful means of screening for new ligands with strong chelate capability to uranyl.« less

  9. Higgs coupling constants as a probe of new physics

    SciTech Connect (OSTI)

    Kanemura, Shinya; Okada, Yasuhiro; Senaha, Eibun; Yuan, C.-P.

    2004-12-01

    We study new physics effects on the couplings of weak gauge bosons with the lightest CP-even Higgs boson (h), hZZ, and the trilinear coupling of the lightest Higgs boson, hhh, at the one-loop order, as predicted by the two Higgs doublet model. Those renormalized coupling constants can deviate from the standard model (SM) predictions due to two distinct origins: the tree level mixing effect of Higgs bosons and the quantum effect of additional particles in loop diagrams. The latter can be enhanced in the renormalized hhh coupling constant when the additional particles show the nondecoupling property. Therefore, even in the case where the hZZ coupling is close to the SM value, deviation in the hhh coupling from the SM value can become as large as plus 100%, while that in the hZZ coupling is at most minus 1% level. Such large quantum effect on the Higgs trilinear coupling is distinguishable from the tree level mixing effect, and is expected to be detectable at a future linear collider.

  10. Constant volume gas cell optical phase-shifter

    DOE Patents [OSTI]

    Phillion, Donald W.

    2002-01-01

    A constant volume gas cell optical phase-shifter, particularly applicable for phase-shifting interferometry, contains a sealed volume of atmospheric gas at a pressure somewhat different than atmospheric. An optical window is present at each end of the cell, and as the length of the cell is changed, the optical path length of a laser beam traversing the cell changes. The cell comprises movable coaxial tubes with seals and a volume equalizing opening. Because the cell is constant volume, the pressure, temperature, and density of the contained gas do not change as the cell changes length. This produces an exactly linear relationship between the change in the length of the gas cell and the change in optical phase of the laser beam traversing it. Because the refractive index difference between the gas inside and the atmosphere outside is very much the same, a large motion must be made to change the optical phase by the small fraction of a wavelength that is required by phase-shifting interferometry for its phase step. This motion can be made to great fractional accuracy.

  11. Silica aerogel: An intrinsically low dielectric constant material

    SciTech Connect (OSTI)

    Hrubesh, L.W.

    1995-04-01

    Silica aerogels are highly porous solids having unique morphologies in wavelength of visible which both the pores and particles have sizes less than the wavelength of visible light. This fine nanostructure modifies the normal transport mechanisms within aerogels and endows them with a variety of exceptional physical properties. For example, aerogels have the lowest measured thermal conductivity and dielectric constant for any solid material. The intrinsically low dielectric properties of silica aerogels are the direct result of the extremely high achievable porosities, which are controllable over a range from 75% to more than 99.8 %, and which result in measured dielectric constants from 2.0 to less than 1.01. This paper discusses the synthesis of silica aerogels, processing them as thin films, and characterizing their dielectric properties. Existing data and other physical characteristics of bulk aerogels (e.g., thermal stablity, thermal expansion, moisture adsorption, modulus, dielectric strength, etc.), which are useful for evaluating them as potential dielectrics for microelectronics, are also given.

  12. Defect distributions in weld-deposited cladding

    SciTech Connect (OSTI)

    Li, Y.Y.; Mabe, W.R.

    1998-11-01

    Defect distributions in stainless steel and nickel-chromium alloy weld-deposited cladding over a low alloy steel base were characterized by destructive evaluation (DE). An evaluation of the observed defects was conducted to characterize the defects by type or classification. Size distributions of cladding defect types were developed from the information obtained. This paper presents the results of the cladding evaluation.

  13. Lieb-Liniger gas in a constant-force potential

    SciTech Connect (OSTI)

    Jukic, D.; Galic, S.; Buljan, H.; Pezer, R.

    2010-08-15

    We use Gaudin's Fermi-Bose mapping operator to calculate exact solutions for the Lieb-Liniger model in a linear (constant-force) potential (the constructed exact stationary solutions are referred to as the Lieb-Liniger-Airy wave functions). The ground-state properties of the gas in the wedgelike trapping potential are calculated in the strongly interacting regime by using Girardeau's Fermi-Bose mapping and the pseudopotential approach in the 1/c approximation (c denotes the strength of the interaction). We point out that quantum dynamics of Lieb-Liniger wave packets in the linear potential can be calculated by employing an N-dimensional Fourier transform as in the case of free expansion.

  14. Prediction of spark kernel development in constant volume combustion

    SciTech Connect (OSTI)

    Lim, M.T.; Anderson, R.W.; Arpaci, V.S.

    1987-09-01

    Combustion initiation is studied in atmospheric pressure propane-air mixtures in a constant volume bomb with a high speed (10,000 fps) laser schlieren system. The spark current and voltage waveforms are simultaneously recorded for later model input. A phenomenological model for early flame kernel development is presented which accounts for the initial, breakdown generated, spark kernel and its subsequent growth. The kernel growth is initially controlled by the breakdown process and the subsequent electrical power input. A new, spark power induced, mass entrainment term is shown to model this initially rapid volume increase adequately while later growth is mainly dominated by diffusion. Results and model comparisons are presented for the effects of power input, spark energy, and equivalence ratio.

  15. Constant power speed range extension of surface mounted PM motors

    DOE Patents [OSTI]

    Lawler, Jack Steward; Bailey, John Milton

    2001-01-01

    A circuit and method for controlling a rotating machine (11) in the constant horsepower range above base speed uses an inverter (15) having SCR's (T1-T6) connected in series with the primary commutation switches (Q1-Q6) to control turn off of the primary commutation switches and to protect the primary commutation switches from faults. The primary commutation switches (Q1-Q6) are controlled by a controller (14), to fire in advance or after a time when the back emf equals the applied voltage, and then to turn off after a precise dwell time, such that suitable power is developed at speeds up to at least six times base speed.

  16. How does pressure gravitate? Cosmological constant problem confronts observational cosmology

    SciTech Connect (OSTI)

    Narimani, Ali; Scott, Douglas; Afshordi, Niayesh E-mail: nafshordi@pitp.ca

    2014-08-01

    An important and long-standing puzzle in the history of modern physics is the gross inconsistency between theoretical expectations and cosmological observations of the vacuum energy density, by at least 60 orders of magnitude, otherwise known as the cosmological constant problem. A characteristic feature of vacuum energy is that it has a pressure with the same amplitude, but opposite sign to its energy density, while all the precision tests of General Relativity are either in vacuum, or for media with negligible pressure. Therefore, one may wonder whether an anomalous coupling to pressure might be responsible for decoupling vacuum from gravity. We test this possibility in the context of the Gravitational Aether proposal, using current cosmological observations, which probe the gravity of relativistic pressure in the radiation era. Interestingly, we find that the best fit for anomalous pressure coupling is about half-way between General Relativity (GR), and Gravitational Aether (GA), if we include Planck together with WMAP and BICEP2 polarization cosmic microwave background (CMB) observations. Taken at face value, this data combination excludes both GR and GA at around the 3 σ level. However, including higher resolution CMB observations (''highL'') or baryonic acoustic oscillations (BAO) pushes the best fit closer to GR, excluding the Gravitational Aether solution to the cosmological constant problem at the 4- 5 σ level. This constraint effectively places a limit on the anomalous coupling to pressure in the parametrized post-Newtonian (PPN) expansion, ζ{sub 4} = 0.105 ± 0.049 (+highL CMB), or ζ{sub 4} = 0.066 ± 0.039 (+BAO). These represent the most precise measurement of this parameter to date, indicating a mild tension with GR (for ΛCDM including tensors, with 0ζ{sub 4}=), and also among different data sets.

  17. Finite-Element Simulation Of Hot-Water-Type Geothermal Reservoirs...

    Open Energy Info (EERE)

    differential equations are based upon constant physical parameters (except fluid density) and formulated for hot-water-type geothermal reservoirs. A simultaneous solution...

  18. DIORAMA Location Type User's Guide

    SciTech Connect (OSTI)

    Terry, James Russell

    2015-01-29

    The purpose of this report is to present the current design and implementation of the DIORAMA location type object (LocationType) and to provide examples and use cases. The LocationType object is included in the diorama-app package in the diorama::types namespace. Abstractly, the object is intended to capture the full time history of the location of an object or reference point. For example, a location may be speci ed as a near-Earth orbit in terms of a two-line element set, in which case the location type is capable of propagating the orbit both forward and backward in time to provide a location for any given time. Alternatively, the location may be speci ed as a xed set of geodetic coordinates (latitude, longitude, and altitude), in which case the geodetic location of the object is expected to remain constant for all time. From an implementation perspective, the location type is de ned as a union of multiple independent objects defi ned in the DIORAMA tle library. Types presently included in the union are listed and described in subsections below, and all conversions or transformation between these location types are handled by utilities provided by the tle library with the exception of the \\special-values" location type.

  19. Systematic corrections to the measured cosmological constant as a result of local inhomogeneity

    SciTech Connect (OSTI)

    Vanderveld, R. Ali; Flanagan, Eanna E.; Wasserman, Ira

    2007-10-15

    We explicitly calculate the lowest order systematic inhomogeneity-induced corrections to the cosmological constant that one would infer from an analysis of the luminosities and redshifts of type Ia supernovae, assuming a homogeneous universe. The calculation entails a post-Newtonian expansion within the framework of second-order perturbation theory, wherein we consider the effects of subhorizon density perturbations in a flat, dust-dominated universe. Within this formalism, we calculate luminosity distances and redshifts along the past light cone of an observer. The luminosity distance-redshift relation is then averaged over viewing angles and ensemble averaged, assuming that density fluctuations at a given cosmic time are a homogeneous random process. The resulting relation is fit to that of a homogeneous model containing dust and a cosmological constant, in order to deduce the best-fit cosmological constant density {omega}{sub {lambda}}. We find that the luminosity distance-redshift relation is indeed modified, even for large sample sizes, but only by a very small fraction, of order 10{sup -5} for z{approx}0.1. This lowest order deviation depends on the peculiar velocities of the source and the observer. However, when fitting this perturbed relation to that of a homogeneous universe, via maximizing a likelihood function, we find that the inferred cosmological constant can be surprisingly large, depending on the range of redshifts sampled. For a sample of supernovae extending from z{sub min}=0.02 out to a limiting redshift z{sub max}=0.15, we find that {omega}{sub {lambda}}{approx_equal}0.004. The value of {omega}{sub {lambda}} has a large variance, and its magnitude tends to get progressively larger as the limiting redshift z{sub max} gets smaller, implying that precision measurements of {omega}{sub {lambda}} from nearby supernova data will require taking this effect into account. This effect has been referred to in the past as the 'fitting problem', and more

  20. Optimum position for wells producing at constant wellbore pressure

    SciTech Connect (OSTI)

    Camacho-Velazquez, R.; Rodriguez de la Garza, F.; Galindo-Nava, A.; Prats, M.

    1994-12-31

    This paper deals with the determination of the optimum position of several wells, producing at constant different wellbore pressures from a two-dimensional closed-boundary reservoirs, to maximize the cumulative production or the total flow rate. To achieve this objective they authors use an improved version of the analytical solution recently proposed by Rodriguez and Cinco-Ley and an optimization algorithm based on a quasi-Newton procedure with line search. At each iteration the algorithm approximates the negative of the objective function by a cuadratic relation derived from a Taylor series. The improvement of rodriguez and Cinco`s solution is attained in four ways. First, an approximation is obtained, which works better at earlier times (before the boundary dominated period starts) than the previous solution. Second, the infinite sums that are present in the solution are expressed in a condensed form, which is relevant for reducing the computer time when the optimization algorithm is used. Third, the solution is modified to take into account the possibility of having wells starting to produce at different times. This point allows them to deal with the problem of getting the optimum position for an infill drilling program. Last, the solution is extended to include the possibility of changing the value of wellbore pressure or being able to stimulate any of the wells at any time. When the wells are producing at different wellbore pressures it is found that the optimum position is a function of time, otherwise the optimum position is fixed.

  1. Varying fine structure 'constant' and charged black holes

    SciTech Connect (OSTI)

    Bekenstein, Jacob D.; Schiffer, Marcelo

    2009-12-15

    Speculation that the fine-structure constant {alpha} varies in spacetime has a long history. We derive, in 4-D general relativity and in isotropic coordinates, the solution for a charged spherical black hole according to the framework for dynamical {alpha} J. D. Bekenstein, Phys. Rev. D 25, 1527 (1982).. This solution coincides with a previously known one-parameter extension of the dilatonic black hole family. Among the notable properties of varying-{alpha} charged black holes are adherence to a 'no hair' principle, the absence of the inner (Cauchy) horizon of the Reissner-Nordstroem black holes, the nonexistence of precisely extremal black holes, and the appearance of naked singularities in an analytic extension of the relevant metric. The exteriors of almost extremal electrically (magnetically) charged black holes have simple structures which makes their influence on applied magnetic (electric) fields transparent. We rederive the thermodynamic functions of the modified black holes; the otherwise difficult calculation of the electric potential is done by a shortcut. We confirm that variability of {alpha} in the wake of expansion of the universe does not threaten the generalized second law.

  2. Constant-complexity stochastic simulation algorithm with optimal binning

    SciTech Connect (OSTI)

    Sanft, Kevin R.; Othmer, Hans G.

    2015-08-21

    At the molecular level, biochemical processes are governed by random interactions between reactant molecules, and the dynamics of such systems are inherently stochastic. When the copy numbers of reactants are large, a deterministic description is adequate, but when they are small, such systems are often modeled as continuous-time Markov jump processes that can be described by the chemical master equation. Gillespie’s Stochastic Simulation Algorithm (SSA) generates exact trajectories of these systems, but the amount of computational work required for each step of the original SSA is proportional to the number of reaction channels, leading to computational complexity that scales linearly with the problem size. The original SSA is therefore inefficient for large problems, which has prompted the development of several alternative formulations with improved scaling properties. We describe an exact SSA that uses a table data structure with event time binning to achieve constant computational complexity with respect to the number of reaction channels for weakly coupled reaction networks. We present a novel adaptive binning strategy and discuss optimal algorithm parameters. We compare the computational efficiency of the algorithm to existing methods and demonstrate excellent scaling for large problems. This method is well suited for generating exact trajectories of large weakly coupled models, including those that can be described by the reaction-diffusion master equation that arises from spatially discretized reaction-diffusion processes.

  3. Type: Renewal

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

    1 INCITE Awards Type: Renewal Title: -Ab Initio Dynamical Simulations for the Prediction of Bulk Properties‖ Principal Investigator: Theresa Windus, Iowa State University Co-Investigators: Brett Bode, Iowa State University Graham Fletcher, Argonne National Laboratory Mark Gordon, Iowa State University Monica Lamm, Iowa State University Michael Schmidt, Iowa State University Scientific Discipline: Chemistry: Physical INCITE Allocation: 10,000,000 processor hours Site: Argonne National

  4. Facility Type!

    Office of Legacy Management (LM)

    ITY: --&L~ ----------- srct-r~ -----------~------~------- if yee, date contacted ------------- cl Facility Type! i I 0 Theoretical Studies Cl Sample 84 Analysis ] Production 1 Diepasal/Storage 'YPE OF CONTRACT .--------------- 1 Prime J Subcontract&- 1 Purchase Order rl i '1 ! Other information (i.e., ---------~---~--~-------- :ontrait/Pirchaee Order # , I C -qXlJ- --~-------~~-------~~~~~~ I I ~~~---~~~~~~~T~~~ FONTRACTING PERIODi IWNERSHIP: ,I 1 AECIMED AECMED GOVT GOUT &NTtiAC+OR

  5. Type here

    Office of Environmental Management (EM)

    Injury at the Savannah River National Laboratory | Department of Energy January 10, 2006, Flash Fire and Injury at the Savannah River National Laboratory Type B Accident Investigation of the January 10, 2006, Flash Fire and Injury at the Savannah River National Laboratory February 1, 2006 On January 10, 2006, at approximately 7:47 a.m., a first-line manager (FLM) at the Savannah River National Laboratory (SRNL) received first- and second-degree burns to his head, face, neck, and left hand

  6. Effect of lattice deformation on exchange coupling constants in Cr{sub 2}O{sub 3}

    SciTech Connect (OSTI)

    Kota, Yohei; Imamura, Hiroshi; Sasaki, Munetaka

    2014-05-07

    We studied lattice deformation effect on exchange interaction in the corundum-type Cr{sub 2}O{sub 3} theoretically. First-principles electronic structure calculations were performed to evaluate the total energy and exchange coupling constants of Cr{sub 2}O{sub 3} under lattice deformation. We found that a few percent elastic deformation is expected via misfit strain and that the first- and second-nearest neighbor exchange coupling constants of Cr{sub 2}O{sub 3} strongly depend on the lattice deformation. These results imply a possibility for improving the thermal stability of Cr{sub 2}O{sub 3} based magnetoelectric devices by lattice deformation.

  7. EIA - Coal Distribution

    Gasoline and Diesel Fuel Update (EIA)

    Annual Coal Distribution Report > Annual Coal Distribution Archives Annual Coal Distribution Archive Release Date: February 17, 2011 Next Release Date: December 2011 Domestic coal ...

  8. Measures of microstructure to improve estimates and bounds on elastic constants and transport coefficients in heterogeneous media

    SciTech Connect (OSTI)

    Berryman, J G

    2004-10-07

    The most commonly discussed measures of microstructure in composite materials are the spatial correlation functions, which in a porous medium measure either the grain-to-grain correlations, or the pore-to-pore correlations in space. Improved bounds based on this information such as the Beran-Molyneux bounds for bulk modulus and the Beran bounds for conductivity are well-known. It is first shown here how to make direct use of this information to provide estimates that always lie between these upper and lower bounds for any microstructure whenever the microgeometry parameters are known. Then comparisons are made between these estimates, the bounds, and two new types of estimates. One new estimate for elastic constants makes use of the Peselnick-Meister bounds (based on Hashin-Shtrikman methods) for random polycrystals of laminates to generate self-consistent values that always lie between the bounds. A second new type of estimate for conductivity assumes that measurements of formation factors (of which there are at least two distinct types in porous media, associated respectively with pores and grains) are available, and computes new bounds based on this information. The paper compares and contrasts these various methods in order to clarify just what microstructural information and how precisely that information needs to be known in order to be useful for estimating material constants in random and heterogeneous media.

  9. Measured dose rate constant from oncology patients administered 18F for positron emission tomography

    SciTech Connect (OSTI)

    Quinn, Brian; Holahan, Brian; Aime, Jean; Humm, John; St Germain, Jean; Dauer, Lawrence T.

    2012-10-15

    patients immediately following injection. This value can then be reliably scaled to the desired time and distance for planning and staff dose evaluation purposes. At distances closer than 1 m, a distance-specific dose rate constant of 0.367 {mu}Sv/MBq h at 30 cm is recommended for accurate calculations. An accurate patient-specific dose rate constant that accounts for patient-specific variables (e.g., distribution and attenuation) will allow an accurate evaluation of the dose rate from a patient injected with an isotope rather than simply utilizing a physical constant.

  10. Feasibility study of volumetric modulated arc therapy with constant dose rate for endometrial cancer

    SciTech Connect (OSTI)

    Yang, Ruijie; Wang, Junjie; Xu, Feng; Li, Hua; Zhang, Xile

    2013-10-01

    To investigate the feasibility, efficiency, and delivery accuracy of volumetric modulated arc therapy with constant dose rate (VMAT-CDR) for whole-pelvic radiotherapy (WPRT) of endometrial cancer. The nine-field intensity-modulated radiotherapy (IMRT), VMAT with variable dose-rate (VMAT-VDR), and VMAT-CDR plans were created for 9 patients with endometrial cancer undergoing WPRT. The dose distribution of planning target volume (PTV), organs at risk (OARs), and normal tissue (NT) were compared. The monitor units (MUs) and treatment delivery time were also evaluated. For each VMAT-CDR plan, a dry run was performed to assess the dosimetric accuracy with MatriXX from IBA. Compared with IMRT, the VMAT-CDR plans delivered a slightly greater V{sub 20} of the bowel, bladder, pelvis bone, and NT, but significantly decreased the dose to the high-dose region of the rectum and pelvis bone. The MUs decreased from 1105 with IMRT to 628 with VMAT-CDR. The delivery time also decreased from 9.5 to 3.2 minutes. The average gamma pass rate was 95.6% at the 3%/3 mm criteria with MatriXX pretreatment verification for 9 patients. VMAT-CDR can achieve comparable plan quality with significant shorter delivery time and smaller number of MUs compared with IMRT for patients with endometrial cancer undergoing WPRT. It can be accurately delivered and be an alternative to IMRT on the linear accelerator without VDR capability.

  11. Finite element approximation of the radiative transport equation in a medium with piece-wise constant refractive index

    SciTech Connect (OSTI)

    Lehtikangas, O.; Tarvainen, T.; Kim, A.D.; Arridge, S.R.

    2015-02-01

    The radiative transport equation can be used as a light transport model in a medium with scattering particles, such as biological tissues. In the radiative transport equation, the refractive index is assumed to be constant within the medium. However, in biomedical media, changes in the refractive index can occur between different tissue types. In this work, light propagation in a medium with piece-wise constant refractive index is considered. Light propagation in each sub-domain with a constant refractive index is modeled using the radiative transport equation and the equations are coupled using boundary conditions describing Fresnel reflection and refraction phenomena on the interfaces between the sub-domains. The resulting coupled system of radiative transport equations is numerically solved using a finite element method. The approach is tested with simulations. The results show that this coupled system describes light propagation accurately through comparison with the Monte Carlo method. It is also shown that neglecting the internal changes of the refractive index can lead to erroneous boundary measurements of scattered light.

  12. Stress corrosion cracking of alloy 600 using the constant strain rate test

    SciTech Connect (OSTI)

    Bulischeck, T. S.; van Rooyen, D.

    1980-01-01

    The most recent corrosion problems experienced in nuclear steam generators tubed with Inconel alloy 600 is a phenomenon labeled ''denting''. Denting has been found in various degrees of severity in many operating pressurized water reactors. Laboratory investigations have shown that Inconel 600 exhibits intergranular SCC when subjected to high stresses and exposed to deoxygenated water at elevated temperatures. A research project was initiated at Brookhaven National Laboratory in an attempt to improve the qualitative and quantitative understanding of factors influencing SCC in high temperature service-related environments. An effort is also being made to develop an accelerated test method which could be used to predict the service life of tubes which have been deformed or are actively denting. Several heats of commercial Inconel 600 tubing were procured for testing in deaerated pure and primary water at temperatures from 290 to 365/sup 0/C. U-bend type specimens were used to determine crack initiation times which may be expected for tubes where denting has occurred but is arrested and provide baseline data for judging the accelerating effects of the slow strain rate method. Constant extension rate tests were employed to determine the crack velocities experienced in the crack propagation stage and predict failure times of tubes which are actively denting. 8 refs., 17 figs., 5 tabs.

  13. Structure disorder degree of polysilicon thin films grown by different processing: Constant C from Raman spectroscopy

    SciTech Connect (OSTI)

    Wang, Quan; Zhang, Yanmin; Hu, Ran; Ren, Naifei; Ge, Daohan

    2013-11-14

    Flat, low-stress, boron-doped polysilicon thin films were prepared on single crystalline silicon substrates by low pressure chemical vapor deposition. It was found that the polysilicon films with different deposition processing have different microstructure properties. The confinement effect, tensile stresses, defects, and the Fano effect all have a great influence on the line shape of Raman scattering peak. But the effect results are different. The microstructure and the surface layer are two important mechanisms dominating the internal stress in three types of polysilicon thin films. For low-stress polysilicon thin film, the tensile stresses are mainly due to the change of microstructure after thermal annealing. But the tensile stresses in flat polysilicon thin film are induced by the silicon carbide layer at surface. After the thin film doped with boron atoms, the phenomenon of the tensile stresses increasing can be explained by the change of microstructure and the increase in the content of silicon carbide. We also investigated the disorder degree states for three polysilicon thin films by analyzing a constant C. It was found that the disorder degree of low-stress polysilicon thin film larger than that of flat and boron-doped polysilicon thin films due to the phase transformation after annealing. After the flat polysilicon thin film doped with boron atoms, there is no obvious change in the disorder degree and the disorder degree in some regions even decreases.

  14. Structural and magnetic characterization of electro-crystallized magnetite nanoparticles under constant current

    SciTech Connect (OSTI)

    Mosivand, Saba; Kazeminezhad, Iraj

    2015-10-15

    Graphical abstract: Structural and magnetic properties of electro-crystallized magnetite nanoparticles under constant current were studied. All samples were characterized using XRD, SEM, VSM, and Mössbauer spectrometry. - Highlights: • The effect of applied current on morphology and properties of Fe{sub 3}O{sub 4} is studied. • The particle size and morphology are controllable by adjusting the current. • The magnetization depends on particle size, type of surfactant and applied current. • The clear correlation between magnetization and the mean particle size is observed. - Abstract: The effect of applied current on the morphology, particle size, structure, and magnetic properties of magnetite nanoparticles prepared by electro-crystallization method was studied. The synthesis was performed in an electrochemical cell containing two iron electrodes and an aqueous solution of sodium sulfate, and either thiourea, sodium butanoate, or β-cyclodextrine as organic stabilizer. All the samples were characterized by XRD, SEM, VSM, and Mössbauer spectroscopy. X-ray diffraction patterns, clearly confirmed that all products have the cubic spinel Fe{sub 3}O{sub 4} crystal structure. Electron microscope images of the samples showed that their mean particle size is in the range 20–80 nm, and depends critically on the applied current and type of the organic additives. Specific magnetization of the samples at room temperature ranges from 60 to 90 A m{sup 2} kg{sup −1}, depending on the growth conditions. Room temperature Mössbauer spectra are typical of nonstoichiometric Fe{sub 3−δ}O{sub 4}, with a small excess of Fe{sup 3+}, 0.06 ≤ δ ≤ 0.17.

  15. Layered Copper-Based Electrode for High-Dielectric Constant Oxide...

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

    Copper-Based Electrode for High-Dielectric Constant Oxide Thin-Film-Based Devices Technology available for licenisng: A multilayer thin-film device containing copper layers ...

  16. ETA-HITP04 - HICE Vehicle Constant Speed Fuel Economy Tests

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

    Appendices Appendix A - 45 mph Constant Speed Range Test Data Sheet 10 Appendix B - Calibration of Vehicle Speedometer Test Data Sheet 12 Appendix C - Vehicle Metrology Setup Sheet ...

  17. ETA-HTP04 - Hybrid Electric Vehicle Constant Speed Range Tests...

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

    Appendices Appendix A - 45 mph Constant Speed Range Test Data Sheet 11 Appendix B - Maximum Achievable Speed Range Test Data Sheet 13 Appendix C - Calibration of Vehicle ...

  18. Wigner phase space distribution via classical adiabatic switching

    SciTech Connect (OSTI)

    Bose, Amartya; Makri, Nancy

    2015-09-21

    Evaluation of the Wigner phase space density for systems of many degrees of freedom presents an extremely demanding task because of the oscillatory nature of the Fourier-type integral. We propose a simple and efficient, approximate procedure for generating the Wigner distribution that avoids the computational difficulties associated with the Wigner transform. Starting from a suitable zeroth-order Hamiltonian, for which the Wigner density is available (either analytically or numerically), the phase space distribution is propagated in time via classical trajectories, while the perturbation is gradually switched on. According to the classical adiabatic theorem, each trajectory maintains a constant action if the perturbation is switched on infinitely slowly. We show that the adiabatic switching procedure produces the exact Wigner density for harmonic oscillator eigenstates and also for eigenstates of anharmonic Hamiltonians within the Wentzel-Kramers-Brillouin (WKB) approximation. We generalize the approach to finite temperature by introducing a density rescaling factor that depends on the energy of each trajectory. Time-dependent properties are obtained simply by continuing the integration of each trajectory under the full target Hamiltonian. Further, by construction, the generated approximate Wigner distribution is invariant under classical propagation, and thus, thermodynamic properties are strictly preserved. Numerical tests on one-dimensional and dissipative systems indicate that the method produces results in very good agreement with those obtained by full quantum mechanical methods over a wide temperature range. The method is simple and efficient, as it requires no input besides the force fields required for classical trajectory integration, and is ideal for use in quasiclassical trajectory calculations.

  19. Double distributions and evolution equations

    SciTech Connect (OSTI)

    A.V. Radyushkin

    1998-05-01

    Applications of perturbative QCD to deeply virtual Compton scattering and hard exclusive meson electroproduction processes require a generalization of usual parton distributions for the case when long-distance information is accumulated in nonforward matrix elements < p{prime} {vert_bar}O(0,z){vert_bar}p > of quark and gluon light-cone operators. In their previous papers the authors used two types of nonperturbative functions parameterizing such matrix elements: double distributions F(x,y;t) and nonforward distribution functions F{sub {zeta}}(X;t). Here they discuss in more detail the double distributions (DD's) and evolution equations which they satisfy. They propose simple models for F(x,y;t=0) DD's with correct spectral and symmetry properties which also satisfy the reduction relations connecting them to the usual parton densities f(x). In this way, they obtain self-consistent models for the {zeta}-dependence of nonforward distributions. They show that, for small {zeta}, one can easily obtain nonforward distributions (in the X > {zeta} region) from the parton densities: F{sub {zeta}} (X;t=0) {approx} f(X{minus}{zeta}/2).

  20. Distribution System planning for Smart Grids, ForskEL (Smart...

    Open Energy Info (EERE)

    Name Distribution System planning for Smart Grids, ForskEL Country Denmark Coordinates 56.26392, 9.501785 Loading map... "minzoom":false,"mappingservice":"googlemaps3","type...

  1. Distribution Grid Integration

    Broader source: Energy.gov [DOE]

    The DOE Systems Integration team funds distribution grid integration research and development (R&D) activities to address the technical issues that surround distribution grid planning,...

  2. Annual Coal Distribution Report

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

    Annual Coal Distribution Report Release Date: April 16, 2015 | Next Release Date: March 2016 | full report | RevisionCorrection Revision to the Annual Coal Distribution Report ...

  3. About Industrial Distributed Energy

    Broader source: Energy.gov [DOE]

    The Advanced Manufacturing Office's (AMO's) Industrial Distributed Energy activities build on the success of predecessor DOE programs on distributed energy and combined heat and power (CHP) while...

  4. Coal Distribution Database, 2006

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

    Domestic Distribution of U.S. Coal by Origin State, Consumer, Destination and Method of Transportation, 2009 Final February 2011 2 Overview of 2009 Coal Distribution Tables...

  5. Ab initio calculations of polarization, piezoelectric constants, and elastic constants of InAs and InP in the wurtzite phase

    SciTech Connect (OSTI)

    Hajlaoui, C. Pedesseau, L.; Raouafi, F.; Ben Cheikh Larbi, F.; Even, J.; Jancu, J.-M.

    2015-08-15

    We report first-principle density functional calculations of the spontaneous polarization, piezoelectric stress constants, and elastic constants for the III–V wurtzite structure semiconductors InAs and InP. Using the density functional theory implemented in the VASP code, we obtain polarization values–0.011 and–0.013 C/m{sup 2}, and piezoelectric constants e{sub 33} (e{sub 31}) equal to 0.091 (–0.026) and 0.012 (–0.081) C/m{sup 2} for structurally relaxed InP and InAs respectively. These values are consistently smaller than those of nitrides. Therefore, we predict a smaller built-in electric field in such structures.

  6. Annual Coal Distribution

    Reports and Publications (EIA)

    2016-01-01

    The Annual Coal Distribution Report (ACDR) provides detailed information on domestic coal distribution by origin state, destination state, consumer category, and method of transportation. Also provided is a summary of foreign coal distribution by coal-producing state. All data for the report year are final and this report supersedes all data in the quarterly distribution reports.

  7. Annual Coal Distribution

    Reports and Publications (EIA)

    2015-01-01

    The Annual Coal Distribution Report (ACDR) provides detailed information on domestic coal distribution by origin state, destination state, consumer category, and method of transportation. Also provided is a summary of foreign coal distribution by coal-producing state. All data for the report year are final and this report supersedes all data in the quarterly distribution reports.

  8. Distributed Wind Ordinances: Slides

    Wind Powering America (EERE)

    an introduction to distributed wind projects and a brief overview of topics to consider when developing a distributed wind energy ordinance. Distributed Wind Ordinances Photo from Byers and Renier Construction, NREL 18820 Distributed Wind Ordinances The U.S. Department of Energy defines distributed wind projects as: (a) The use of wind turbines, on- or off-grid, at homes, farms and ranches, businesses, public and industrial facilities, or other sites to offset all or a portion of the local

  9. EIA -Quarterly Coal Distribution

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

    - Coal Distribution Quarterly Coal Distribution Archives Release Date: August 17, 2016 Next Release Date: December 22, 2016 The Quarterly Coal Distribution Report (QCDR) provides detailed quarterly data on U.S. domestic coal distribution by coal origin, coal destination, mode of transportation and consuming sector. All data are preliminary and superseded by the final Coal Distribution - Annual Report. Year/Quarters By origin State By destination State Report Data File Report Data File 2009

  10. Local Soot Loading Distribution in Cordierite Diesel Particulate Filters by Dynamic Neutron Radiography

    Broader source: Energy.gov [DOE]

    Quantitative analysis of the soot loading and soot distribution for Cordierite type DPFs are studied under controlled conditions.

  11. Sandia Energy - Distribution Grid Integration

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

    Distribution Grid Integration Home Stationary Power Energy Conversion Efficiency Solar Energy Photovoltaics Grid Integration Distribution Grid Integration Distribution Grid...

  12. Leptonic B- and D-Meson Decay Constants with 2+1 Flavors of Asqtad Fermions

    SciTech Connect (OSTI)

    Neil, Ethan T.; Simone, James N.; Van de Water, Ruth S.; Kronfeld, Andreas S.

    2015-01-08

    We present the status of our updated D- and B-meson decay-constant analysis, based on the MILC Nf =2+1 asqtad gauge ensembles. Heavy quarks are incorporated using the Wilson clover action with the Fermilab interpretation. This analysis includes ensembles at five lattice spacings from α ≈ 0.045 to 0.15 fm, and light sea-quark masses down to 1/20th of the strange-quark mass. Projected error budgets for ratios of decay constants, in particular between bottom- and charm-meson decay constants, are presented.

  13. Elastic constants of, and Stonely waves in, molybdenum films measured by Brillouin scattering

    SciTech Connect (OSTI)

    Bell, J.A.; Zanoni, R.; Seaton, C.T.; Stegeman, G.I.; Makous, J.; Falco, C.M.

    1988-02-22

    The dispersion of Rayleigh, Stonely, and Sezawa acoustic waves guided by deposited thin molybdenum films has been used to evaluate selected elastic constants and film homogeneity. This work includes the first experimental observation of Stonely waves by Brillouin scattering.

  14. Determination of magneto-optical constant of Fe films with weak measurements

    SciTech Connect (OSTI)

    Qiu, Xiaodong; Hu, Dejiao; Du, Jinglei; Gao, Fuhua; Zhang, Zhiyou; Zhou, Xinxing; Luo, Hailu

    2014-09-29

    In this letter, a detecting method for the magneto-optical constant is presented by using weak measurements. The photonic spin Hall effect (PSHE), which manifests itself as spin-dependent splitting, is introduced to characterize the magneto-optical constant, and a propagation model to describe the quantitative relation between the magneto-optical constant and the PSHE is established. According to the amplified shift of the PSHE detected by weak measurements, we determinate the magneto-optical constant of the Fe film sample. The Kerr rotation is measured via the standard polarimetry method to verify the rationality and feasibility of our method. These findings may provide possible applications in magnetic physics research.

  15. Distributed Wind 2015

    Broader source: Energy.gov [DOE]

    Distributed Wind 2015 is committed to the advancement of both distributed and community wind energy. This two day event includes a Business Conference with sessions focused on advancing the...

  16. Doubly Distributed Transactions

    Energy Science and Technology Software Center (OSTI)

    2014-08-25

    Doubly Distributed Transactions (D2T) offers a technique for managing operations from a set of parallel clients with a collection of distributed services. It detects and manages faults. Example code with a test harness is also provided

  17. Fenestration systems as luminaries of varying candlepower distribution

    SciTech Connect (OSTI)

    Papamichael, K.

    1990-10-01

    Simulation of the performance of electric lighting systems has been successfully handled using computers, since electric lighting systems have a constant luminous output with respect to intensity and spatial distribution, usually referred to as candlepower distribution, which can be measured and used conveniently. This paper describes an approach of treating fenestration systems as luminaries of varying candlepower distribution, so that the determination of their luminous performance becomes consistent with that of electric lighting systems. The transmitted distribution through fenestration systems due to radiation from the sun, sky and ground is determined from their bidirectional transmittance and the luminance distribution of the sources of radiation. The approach is demonstrated using the experimentally determined bidirectional transmittance of a diffusive sample under the uniform, overcast and clear sky luminance distributions. 6 refs., 14 figs.

  18. Superthermal electron distribution measurements from polarized electron cyclotron emission

    SciTech Connect (OSTI)

    Luce, T.C.; Efthimion, P.C.; Fisch, N.J.

    1988-06-01

    Measurements of the superthermal electron distribution can be made by observing the polarized electron cyclotron emission. The emission is viewed along a constant magnetic field surface. This simplifies the resonance condition and gives a direct correlation between emission frequency and kinetic energy of the emitting electron. A transformation technique is formulated which determines the anisotropy of the distribution and number density of superthermals at each energy measured. The steady-state distribution during lower hybrid current drive and examples of the superthermal dynamics as the runaway conditions is varied are presented for discharges in the PLT tokamak. 15 refs., 8 figs.

  19. Deuterium concentration and cold fusion; Rate distributions in palladium

    SciTech Connect (OSTI)

    Rogers, V.C.; Sandquist, G.M.; Nielson, K.K. )

    1989-12-01

    Cold fusion reactions and excess heat production have been reported in the electrolysis of heavy water with a palladium metal cathode. Solution of the standard diffusion equation for deuterium without fusion indicates that the deuterium concentration distribution rapidly becomes constant in the palladium lattice. Solution of the nonlinear diffusion equation for deuterium undergoing fusion also gives constant deuterium concentrations, suggesting that any fusion occurs uniformly throughout the palladium lattice. The hypothesis that fusion reactions occur predominantly at the palladium surface is shown to be inconsistent with experimental data.

  20. ARM - Measurement - Cloud type

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

    Measurement : Cloud type Cloud type such as cirrus, stratus, cumulus etc Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the...

  1. Integrated Transmission and Distribution Control

    SciTech Connect (OSTI)

    Kalsi, Karanjit; Fuller, Jason C.; Tuffner, Francis K.; Lian, Jianming; Zhang, Wei; Marinovici, Laurentiu D.; Fisher, Andrew R.; Chassin, Forrest S.; Hauer, Matthew L.

    2013-01-16

    allows the load flow interactions between the bulk power system and end-use loads to be explicitly modeled. Power system interactions are modeled down to time intervals as short as 1-second. Another practical issue is that the size and complexity of typical distribution systems makes direct integration with transmission models computationally intractable. Hence, the focus of the next main task is to develop reduced-order controllable models for some of the smart grid assets. In particular, HVAC units, which are a type of Thermostatically Controlled Loads (TCLs), are considered. The reduced-order modeling approach can be extended to other smart grid assets, like water heaters, PVs and PHEVs. Closed-loop control strategies are designed for a population of HVAC units under realistic conditions. The proposed load controller is fully responsive and achieves the control objective without sacrificing the end-use performance. Finally, using the T&D simulation platform, the benefits to the bulk power system are demonstrated by controlling smart grid assets under different demand response closed-loop control strategies.

  2. Distributed generation systems model

    SciTech Connect (OSTI)

    Barklund, C.R.

    1994-12-31

    A slide presentation is given on a distributed generation systems model developed at the Idaho National Engineering Laboratory, and its application to a situation within the Idaho Power Company`s service territory. The objectives of the work were to develop a screening model for distributed generation alternatives, to develop a better understanding of distributed generation as a utility resource, and to further INEL`s understanding of utility concerns in implementing technological change.

  3. Room-temperature elastic constants of Sc and ScD[sub 0. 18

    SciTech Connect (OSTI)

    Leisure, R.G. ); Schwarz, R.B.; Migliori, A.; Lei, M. )

    1993-07-01

    The complete set of elastic constants for Sc and ScD[sub 0.18] has been measured at room temperature. The results show that the addition of hydrogen to this rare-earth metal has a qualitatively different effect than the addition of hydrogen to transition metals such as palladium, vanadium, niobium, and tantalum. In the case of Sc all five elastic constants increase with the addition of hydrogen. The bulk modulus for ScD[sub 0.18] is 9.5% higher than that for Sc. The Debye temperature computed from the room-temperature elastic constants is 355 K for Sc and 371 K for ScD[sub 0.18].

  4. Coal Distribution Database, 2006

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

    TF RailroadVesselShip Fuel It is also noted that Destination State code of "X Export" indicates movements to foreign destinations. 1 68 Domestic Coal Distribution...

  5. Distribution of Correspondence

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1996-08-30

    Defines correct procedures for distribution of correspondence to the Naval Reactors laboratories. Does not cancel another directive. Expired 8-30-97.

  6. Ductless Hydronic Distribution Systems

    Broader source: Energy.gov [DOE]

    This presentation is from a Building America webinar conducted on November 8, 2011, by the Alliance for Residential Building Innovation (ARBI) about ductless hydronic distribution systems.

  7. PV distribution system

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

    distribution system - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us ... Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & ...

  8. Distribution Grid Integration

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

    Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & ... of the distributed, or local, power generation into the electric power system. ...

  9. Annual Coal Distribution Tables

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

    Domestic Distribution of U.S. Coal by Destination State, Consumer, Destination and Method of Transportation, 2001 (Thousand Short Tons) DESTINATION: Alabama State of Origin by...

  10. Coal Distribution Database, 2006

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

    Report - Annual provides detailed information on domestic coal distribution by origin state, destination state, consumer category, and method of transportation. Also provided is...

  11. Cooling water distribution system

    DOE Patents [OSTI]

    Orr, Richard

    1994-01-01

    A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

  12. Electronic constant current and current pulse signal generator for nuclear instrumentation testing

    DOE Patents [OSTI]

    Brown, Roger A.

    1994-01-01

    Circuitry for testing the ability of an intermediate range nuclear instrut to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is applied to the instrument. When the LED is off, a constant current is applied. An inductor opposes battery current flow when the LED is on.

  13. Lattice study of the leptonic decay constant of the pion and its excitations

    SciTech Connect (OSTI)

    Mastropas, Ekaterina; Richard, David

    2014-11-01

    We present a calculation of the decay constant of the pion, and its lowest-lying three excitations, at three values of the pion mass between around 400 and 700 MeV, using anisotropic clover lattices. We use the variational method to determine an optimal interpolating operator for each of the states. We find that the decay constant of the first excitation, and more notably of the second, is suppressed with respect to that of the ground-state pion, but that the suppression shows little dependence on the quark mass.

  14. Reduction of magnetic damping constant of FeCo films by rare-earth Gd doping

    SciTech Connect (OSTI)

    Guo, Xiaobin; Xi, Li Li, Yue; Han, Xuemeng; Li, Dong; Wang, Zhen; Zuo, Yalu

    2014-08-18

    Magnetic damping constant (α) is one of the key parameters to determine the critical current density of spin-transfer-torque devices and the switching time of magnetization for ultra-high-frequency devices. In this work, Gd doped FeCo films were fabricated to investigate α based on the ferromagnetic resonance technique. Gd doping not only can efficiently decrease the magnetic inhomogeneity and the extrinsic part of α but also the Landé g-factor and intrinsic part of α. The obtained α was roughly proportional to (g-2){sup 2} and the magnetic anisotropic constant, indicating that the decreased spin-orbit interaction decreases α by Gd doping.

  15. Electronic constant current and current pulse signal generator for nuclear instrumentation testing

    DOE Patents [OSTI]

    Brown, R.A.

    1994-04-19

    Circuitry is described for testing the ability of an intermediate range nuclear instrument to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is applied to the instrument. When the LED is off, a constant current is applied. An inductor opposes battery current flow when the LED is on. 1 figures.

  16. Smart distribution systems

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

    Jiang, Yazhou; Liu, Chen -Ching; Xu, Yin

    2016-04-19

    The increasing importance of system reliability and resilience is changing the way distribution systems are planned and operated. To achieve a distribution system self-healing against power outages, emerging technologies and devices, such as remote-controlled switches (RCSs) and smart meters, are being deployed. The higher level of automation is transforming traditional distribution systems into the smart distribution systems (SDSs) of the future. The availability of data and remote control capability in SDSs provides distribution operators with an opportunity to optimize system operation and control. In this paper, the development of SDSs and resulting benefits of enhanced system capabilities are discussed. Amore » comprehensive survey is conducted on the state-of-the-art applications of RCSs and smart meters in SDSs. Specifically, a new method, called Temporal Causal Diagram (TCD), is used to incorporate outage notifications from smart meters for enhanced outage management. To fully utilize the fast operation of RCSs, the spanning tree search algorithm is used to develop service restoration strategies. Optimal placement of RCSs and the resulting enhancement of system reliability are discussed. Distribution system resilience with respect to extreme events is presented. Furthermore, test cases are used to demonstrate the benefit of SDSs. Active management of distributed generators (DGs) is introduced. Future research in a smart distribution environment is proposed.« less

  17. Probing variations in fundamental constants with radio and optical quasar absorption-line observations.

    SciTech Connect (OSTI)

    Tzanavaris, P.; Murphy, M. T.; Webb, J. K.; Flambaum, V. V.; Curran, S. J.; Physics; Univ. of New South Wales; Inst. of Astronomy

    2007-01-01

    Nine quasar absorption spectra at 21-cm and ultraviolet (UV) rest-frame wavelengths are used to estimate possible variations in x {triple_bond} {alpha}{sup 2}g{sub p}{mu}, where {alpha} is the fine structure constant, g{sub p} the proton g-factor and {mu} {triple_bond} m{sub e}/m{sub p} is the electron-to-proton mass ratio. We find <{Delta}x/x>{sub total}{sup weighted} = (0.63 {+-} 0.99) x 10{sup -5} over a redshift range 0.23 {le} z{sub abs} {le} 2.35 which corresponds to look-back times of 2.7-10.5 billion years. A linear fit against look-back time, tied to {Delta}x/x = 0 at z = 0, gives a best-fitting rate of change of {dot x}/x = (-0.6 {+-} 1.2) x 10{sup -5} yr{sup -1}. We find no evidence for strong angular variations in x across the sky. Our sample is much larger than most previous samples and demonstrates that intrinsic line-of-sight velocity differences between the 21-cm and UV absorption redshifts, which have a random sign and magnitude in each absorption system, limit our precision. The data directly imply that the average magnitude of this difference is {Delta}v{sub los}-6 km s{sup -1}. Combining our {Delta}x/x measurement with absorption-line constraints on {alpha}-variation yields strong limits on the variation of {mu}. Our most conservative estimate, obtained by assuming no variations in {alpha} or g{sub p} is simply {Delta}{mu}/{mu} = <{Delta}x/x>{sub total}{sup weighted}. If we use only the four high-redshift absorbers in our sample, we obtain {Delta}{mu}/{mu} = (0.58 {+-} 1.95) x 10{sup -5}, which agrees (2{sigma}) with recent, more direct estimates from two absorption systems containing molecular hydrogen, also at high redshift, and which have hinted at a possible {mu}-variation, {Delta}{mu}/{mu} = (-2.0 {+-} 0.6) x 10{sup -5}. Our method of constraining {Delta}{mu}/{mu} is completely independent from the molecular hydrogen observations. If we include the low-redshift systems, our {Delta}{mu}/{mu} result differs significantly from the high

  18. Black hole solutions of dimensionally reduced Einstein-Gauss-Bonnet gravity with a cosmological constant

    SciTech Connect (OSTI)

    Melis, M.; Mignemi, S.

    2007-01-15

    We study the phase space of the spherically symmetric solutions of the system obtained from the dimensional reduction of the six-dimensional Einstein-Gauss-Bonnet action with a cosmological constant. We show that all the physical solutions have anti-de Sitter asymptotic behavior.

  19. Brane gravity, massless bulk scalar, and self-tuning of the cosmological constant

    SciTech Connect (OSTI)

    Kim, Jihn E.; Kyae, Bumseok; Shafi, Qaisar

    2004-09-15

    We show that a self-tuning mechanism of the cosmological constant could work in 5D noncompact space-time with a Z{sub 2} symmetry in the presence of a massless scalar field. The standard model matter fields live only on the 4D brane. The change of vacuum energy on the brane (brane cosmological constant) by, for instance, electroweak and QCD phase transitions, just gives rise to dynamical shifts of the profiles of the background metric and the scalar field in the extra dimension, keeping 4D space-time flat without any fine-tuning. To avoid naked singularities in the bulk, the brane cosmological constant should be negative. We introduce an additional brane-localized 4D Einstein-Hilbert term so as to provide the observed 4D gravity with the noncompact extra dimension. With a general form of the brane-localized gravity term allowed by the symmetries, the low energy Einstein gravity is successfully reproduced on the brane at long distances. We show this phenomenon explicitly for the case of vanishing bulk cosmological constant.

  20. Distribution Workshop | Department of Energy

    Office of Environmental Management (EM)

    Variable distributed generation Dispatchable distributed generation Electric vehicle charging and electrolyzers Energy storage Building and industrial loads and demand response ...

  1. WINDExchange: Distributed Wind

    Wind Powering America (EERE)

    Distributed Wind Photo of a small wind turbine next to a farm house with a colorful sunset in the background. The distributed wind market includes wind turbines and projects of many sizes, from small wind turbines less than 1 kilowatt (kW) to multi-megawatt wind farms. The term "distributed wind" describes off-grid or grid-connected wind turbines at homes, farms and ranches, businesses, public and industrial facilities, and other sites. The turbines can provide all of the power used at

  2. Resilient Core Networks for Energy Distribution

    SciTech Connect (OSTI)

    Kuntze, Nicolai; Rudolph, Carsten; Leivesley, Sally; Manz, David O.; Endicott-Popovsky, Barbara E.

    2014-07-28

    Abstract—Substations and their control are crucial for the availability of electricity in today’s energy distribution. Ad- vanced energy grids with Distributed Energy Resources require higher complexity in substations, distributed functionality and communication between devices inside substations and between substations. Also, substations include more and more intelligent devices and ICT based systems. All these devices are connected to other systems by different types of communication links or are situated in uncontrolled environments. Therefore, the risk of ICT based attacks on energy grids is growing. Consequently, security measures to counter these risks need to be an intrinsic part of energy grids. This paper introduces the concept of a Resilient Core Network to interconnected substations. This core network provides essen- tial security features, enables fast detection of attacks and allows for a distributed and autonomous mitigation of ICT based risks.

  3. Types of Reuse

    Broader source: Energy.gov [DOE]

    The following provides greater detail regarding the types of reuse pursued for LM sites. It should be noted that many actual reuses combine several types of the uses listed below.

  4. Shock tube measurements of high temperature rate constants for OH with cycloalkanes and methylcycloalkanes.

    SciTech Connect (OSTI)

    Sivaramakrishnan, R.; Michael, J. V.; Chemical Sciences and Engineering Division

    2009-05-01

    High temperature experiments were performed with the reflected shock tube technique using multi-pass absorption spectrometric detection of OH radicals at 308 nm. The present experiments span a wide T-range, 801-1347 K, and represent the first direct measurements of the title rate constants at T>500 K for cyclopentane and cyclohexane and the only high temperature measurements for the corresponding methyl derivatives. The present work utilized 48 optical passes corresponding to a total path length 4.2 m. As a result of this increased path length, the high [OH] detection sensitivity permitted unambiguous analyses for measuring the title rate constants. The experimental rate constants in units, cm3 molecule-1 s-1, can be expressed in Arrhenius form as k{sub OH+Cyclopentane} = (1.90 {+-} 0.30) x 10{sup -10} exp(-1705 {+-} 156 K/T) (813-1341 K), k{sub OH+Cyclohexane} = (1.86 {+-} 0.24) x 10{sup -10} exp(-1513 {+-} 123 K/T) (801-1347 K), k{sub OH+Methylcyclopentane} = (2.02 {+-} 0.19) x 10{sup -10} exp(-1799 {+-} 96 K/T) (859-1344 K), k{sub OH+Methylcyclohexane} = (2.55 {+-} 0.30) x 10{sup -10} exp(-1824 {+-} 114 K/T) (836-1273 K). These results and lower-T experimental data were used to obtain three parameter evaluations of the experimental rate constants for the title reactions over an even wider T-range. These experimental three parameter fits to the rate constants in units, cm{sup 3} molecule{sup -1} s{sup -1}, are k{sub OH+Cyclopentane} = 1.390 x 10{sup -16}T{sup 1.779} exp(97 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (209-1341 K), k{sub OH+Cyclohexane} = 3.169 x 10{sup -16} T{sup 1.679} exp(119 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (225-1347 K), k{sub OH+Methylcyclopentane} = 6.903 x 10{sup -18}T{sup 2.148} exp(536 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (296-1344 K), k{sub OH+Methylcyclohexane} = 2.341 x 10{sup -18}T{sup 2.325} exp(602 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (296-1273 K). High level electronic structure methods were used to characterize the

  5. Shock tube measurements of high temperature rate constants for OH with cycloalkanes and methylcycloalkanes

    SciTech Connect (OSTI)

    Sivaramakrishnan, R.; Michael, J.V.

    2009-05-15

    High temperature experiments were performed with the reflected shock tube technique using multi-pass absorption spectrometric detection of OH radicals at 308 nm. The present experiments span a wide T-range, 801-1347 K, and represent the first direct measurements of the title rate constants at T>500 K for cyclopentane and cyclohexane and the only high temperature measurements for the corresponding methyl derivatives. The present work utilized 48 optical passes corresponding to a total path length {proportional_to}4.2 m. As a result of this increased path length, the high [OH] detection sensitivity permitted unambiguous analyses for measuring the title rate constants. The experimental rate constants in units, cm{sup 3} molecule{sup -1} s{sup -1}, can be expressed in Arrhenius form as k{sub OH+Cyclopentane}=(1.90{+-}0.30) x 10{sup -10}exp(-1705{+-}56 K/T) (813-1341 K), k{sub OH+Cyclohexane}=(1.86{+-}0.24) x 10{sup -10}exp(-1513{+-}123 K/T) (801-1347 K), k{sub OH+Methylcyclopentane}=(2.02{+-}0.19) x 10{sup -10}exp(-1799{+-}96 K/T) (859-1344 K), k{sub OH+Methylcyclohexane}=(2.55{+-}0.30) x 10{sup -10}exp(-1824{+-}114 K/T) (836-1273 K). These results and lower-T experimental data were used to obtain three parameter evaluations of the experimental rate constants for the title reactions over an even wider T-range. These experimental three parameter fits to the rate constants in units, cm{sup 3} molecule{sup -1} s{sup -1}, are k{sub OH+Cyclopentane}=1.390 x 10{sup -16}T{sup 1.779}exp(97 K/T)cm{sup 3} molecule{sup -1}s{sup -1} (209-1341 K), k{sub OH+Cyclohexane}=3.169 x 10{sup -16}T{sup 1.679}exp(119 K/T)cm{sup 3}molecule{sup -1}s{sup -1} (225-1347 K), k{sub OH+Methylcyclopentane}=6.903 x 10{sup -18}T{sup 2.148}exp(536 K/T)cm{sup 3}molecule{sup -1}s{sup -1} (296-1344 K), k{sub OH+Methylcyclohexane}=2.341 x 10{sup -18}T{sup 2.325}exp(602 K/T)cm{sup 3}molecule{sup -1}s{sup -1} (296-1273 K). High level electronic structure methods were used to characterize the first three

  6. Domestic and Foreign Distribution

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

    of U.S. Coal by State of Origin, 2008 Final May 2010 Domestic and Foreign Distribution of U.S. Coal by State of Origin, 2008 (Thousand Short Tons) State Region Domestic Foreign...

  7. Distributed Energy Resource Program

    Broader source: Energy.gov [DOE]

    Note: A series of orders issued on July 15, 2015 in  Docket 2015-53-E, Docket 2015-54-E, and Docket 2015-55-E approved the incentive programs for South Carolina's Distributed Energy Resource...

  8. Coal Distribution Database, 2008

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

    4Q 2009 April 2010 Quarterly Coal Distribution Table Format and Data Sources 4Q 2009 In keeping with EIA's efforts to increase the timeliness of its reports, this Quarterly Coal...

  9. Coal Distribution Database, 2008

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

    3Q 2009 February 2010 Quarterly Coal Distribution Table Format and Data Sources 3Q 2009 In keeping with EIA's efforts to increase the timeliness of its reports, this Quarterly Coal...

  10. Distributed Wind Energy Workshop

    Broader source: Energy.gov [DOE]

    Join instructor Brent Summerville for a fun and interactive workshop at Appalachian State University's Small Wind Research and Demonstration Site. Learn about a variety of distributed wind energy...

  11. Types of Radiation Exposure

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

    External Irradiation Contamination Incorporation Biological Effects of Acute, Total Body Irradiation Managing Radiation Emergencies Procedure Demonstration Types of radiation ...

  12. Quantum dense key distribution

    SciTech Connect (OSTI)

    Degiovanni, I.P.; Ruo Berchera, I.; Castelletto, S.; Rastello, M.L.; Bovino, F.A.; Colla, A.M.; Castagnoli, G.

    2004-03-01

    This paper proposes a protocol for quantum dense key distribution. This protocol embeds the benefits of a quantum dense coding and a quantum key distribution and is able to generate shared secret keys four times more efficiently than the Bennet-Brassard 1984 protocol. We hereinafter prove the security of this scheme against individual eavesdropping attacks, and we present preliminary experimental results, showing its feasibility.

  13. Hydrogen Pathway Cost Distributions

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

    Pathway Cost Distributions Jim Uihlein Fuel Pathways Integration Tech Team January 25, 2006 2 Outline * Pathway-Independent Cost Goal * Cost Distribution Objective * Overview * H2A Influence * Approach * Implementation * Results * Discussion Process * Summary 3 Hydrogen R&D Cost Goal * Goal is pathway independent * Developed through a well defined, transparent process * Consumer fueling costs are equivalent or less on a cents per mile basis * Evolved gasoline ICE and gasoline-electric

  14. Distributed generation hits market

    SciTech Connect (OSTI)

    1997-10-01

    The pace at which vendors are developing and marketing gas turbines and reciprocating engines for small-scale applications may signal the widespread growth of distributed generation. Loosely defined to refer to applications in which power generation equipment is located close to end users who have near-term power capacity needs, distributed generation encompasses a broad range of technologies and load requirements. Disagreement is inevitable, but many industry observers associate distributed generation with applications anywhere from 25 kW to 25 MW. Ten years ago, distributed generation users only represented about 2% of the world market. Today, that figure has increased to about 4 or 5%, and probably could settle in the 20% range within a 3-to-5-year period, according to Michael Jones, San Diego, Calif.-based Solar Turbines Inc. power generation marketing manager. The US Energy Information Administration predicts about 175 GW of generation capacity will be added domestically by 2010. If 20% comes from smaller plants, distributed generation could account for about 35 GW. Even with more competition, it`s highly unlikely distributed generation will totally replace current market structures and central stations. Distributed generation may be best suited for making market inroads when and where central systems need upgrading, and should prove its worth when the system can`t handle peak demands. Typical applications include small reciprocating engine generators at remote customer sites or larger gas turbines to boost the grid. Additional market opportunities include standby capacity, peak shaving, power quality, cogeneration and capacity rental for immediate demand requirements. Integration of distributed generation systems--using gas-fueled engines, gas-fired combustion engines and fuel cells--can upgrade power quality for customers and reduce operating costs for electric utilities.

  15. Postdoc Appointment Types

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

    Appointment Types Postdoc Appointment Types Most postdocs will be offered a postdoctoral research associate appointment. Each year, approximately 30 Postdoctoral Fellow appointments, including the Distinguished Fellows, are awarded. Postdoc appointment types offer world of possibilities Meet the current LANL Distinguished Postdocs Research Associates Research Associates pursue research as part of ongoing LANL science and engineering programs. Sponsored postdoctoral candidate packages are

  16. Aerodynamic analysis of propeller-type windmills with helical trailing vortices

    SciTech Connect (OSTI)

    Shiao, T.C.

    1980-01-01

    To improve the strip theory for computing the performance of a propeller-type windmill, a more realistic analysis is formulated to include the wake effect. In this dissertation, the finite-wing theory is applied to a rotor blade to find its circulation distribution with the downwash determined from a direct integration of Biot-Savart's law based on the entire helical trailing vortex system. Since no simple analytical solutions can be found for the circulation and the interference factors along a windmill blade, an iterative procedure has been developed to determine the sectional properties at some selected stations. A computer program is constructed for the computation, in which the empirical lift and drag data of the blade airfoil section are programmed. The torque, thrust and power output of the windmill are then obtained by integrating the sectional aerodynamic properties from hub to tip along the blades. Two windmills, one with twisted and tapered blades and the other with uniform blades, are used as examples in predicting the performances. The power computed for the latter windmill agrees well with the measured data. It has been found, according to the computations for the first windmill, that the helical wake may cause a reduction up to 30% in power output of the windmill. The problems of finding the optimum pitch angle for a uniform blade and the optimum distribution of twist angle for a blade of constant chord are considered as some applications of the method derived in this dissertation.

  17. Determining resistivity of a formation adjacent to a borehole having casing by generating constant current flow in portion of casing and using at least two voltage measurement electrodes

    DOE Patents [OSTI]

    Vail, III, William Banning

    2000-01-01

    Methods of operation of different types of multiple electrode apparatus vertically disposed in a cased well to measure information related to the resistivity of adjacent geological formations from within the cased well are described. The multiple electrode apparatus has a minimum of two spaced apart voltage measurement electrodes that electrically engage a first portion of the interior of the cased well and that provide at least first voltage information. Current control means are used to control the magnitude of any selected current that flows along a second portion of the interior of the casing to be equal to a predetermined selected constant. The first portion of the interior of the cased well is spaced apart from the second portion of the interior of the cased well. The first voltage information and the predetermined selected constant value of any selected current flowing along the casing are used in part to determine a magnitude related to the formation resistivity adjacent to the first portion of the interior of the cased well. Methods and apparatus having a plurality of voltage measurement electrodes are disclosed that provide voltage related information in the presence of constant currents flowing along the casing which is used to provide formation resistivity.

  18. Rate constants for OH with selected large alkanes : shock-tube measurements and an improved group scheme.

    SciTech Connect (OSTI)

    Sivaramakrishnan, R.; Michael, J. V.; Chemical Sciences and Engineering Division

    2009-04-30

    } molecule{sup -1} s{sup -1} (241-1287 K); k{sub OH+2,2,3,3-TMB} = 6.835 x 10{sup -17}T{sup 1.886} exp(-365 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (290-1180 K); k{sub OH+n-pentane} = 2.495 x 10{sup -16}T{sup 1.649} exp(80 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (224-1308 K); k{sub OH+n-hexane} = 3.959 x 10{sup -18}T{sup 2.218} exp(443 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (292-1299 K); and k{sub OH+2,3-DMB} = 2.287 x 10{sup -17}T{sup 1.958} exp(365 K/T) cm{sup 3} molecule{sup -1} s{sup -1} (220-1292 K). The experimental data and the evaluations obtained for these five larger alkanes in the present work were used along with prior data/evaluations obtained in this laboratory for H abstractions by OH from a series of smaller alkanes (C{sub 3}?C{sub 5}) to devise rate rules for abstractions from various types of primary, secondary, and tertiary H atoms. Specifically, the current scheme was applied with good success to H abstractions by OH from a series of n-alkanes (n-octane through n-hexadecane). The total rate constants using this group scheme for reactions of OH with selected large alkanes are given as three-parameter fits in this article. The rate constants for the various abstraction channels in any large n-alkane can also be obtained using the groups listed in this article. The present group scheme serves to reduce the uncertainties in rate constants for OH + alkane reactions.

  19. Enhanced sensitivity to the fine-structure-constant variation in the Th IV atomic clock transition

    SciTech Connect (OSTI)

    Flambaum, V. V.; Porsev, S. G.

    2009-12-15

    Our calculations have shown that the 5f{sub 5/2}-7s{sub 1/2} 23 131 cm{sup -1} transition from the ground state in the ion Th{sup 3+} is very sensitive to the temporal variation of the fine-structure constant alpha=e{sup 2}/(Planck constant/2pi)c (q=-75 300 cm{sup -1}). The line is very narrow, the ion has been trapped and laser cooled, and the positive shifter line 5f{sub 5/2}-5f{sub 7/2} 4325 cm{sup -1} (q=+2900 cm{sup -1}) may be used as a reference. A comparison may also be made with a positive shifter in another atom or ion. This makes Th{sup 3+} a good candidate to search for the alpha variation.

  20. Tsunami and acoustic-gravity waves in water of constant depth

    SciTech Connect (OSTI)

    Hendin, Gali; Stiassnie, Michael

    2013-08-15

    A study of wave radiation by a rather general bottom displacement, in a compressible ocean of otherwise constant depth, is carried out within the framework of a three-dimensional linear theory. Simple analytic expressions for the flow field, at large distance from the disturbance, are derived. Realistic numerical examples indicate that the Acoustic-Gravity waves, which significantly precede the Tsunami, are expected to leave a measurable signature on bottom-pressure records that should be considered for early detection of Tsunami.

  1. Inter-atomic force constants of BaF{sub 2} by diffuse neutron scattering measurement

    SciTech Connect (OSTI)

    Sakuma, Takashi Makhsun,; Sakai, Ryutaro; Xianglian; Takahashi, Haruyuki; Basar, Khairul; Igawa, Naoki; Danilkin, Sergey A.

    2015-04-16

    Diffuse neutron scattering measurement on BaF{sub 2} crystals was performed at 10?K and 295?K. Oscillatory form in the diffuse scattering intensity of BaF{sub 2} was observed at 295?K. The correlation effects among thermal displacements of F-F atoms were obtained from the analysis of oscillatory diffuse scattering intensity. The force constants among neighboring atoms in BaF{sub 2} were determined and compared to those in ionic crystals and semiconductors.

  2. Strong coupling constants of heavy baryons with light mesons in QCD

    SciTech Connect (OSTI)

    Aliev, T. M.; Azizi, K.; Savci, M.

    2012-10-23

    The strong coupling constants of the heavy spin-1/2 and spin-3/2 baryons with light pseudoscalar and vector mesons are calculated in the framework of the light cone QCD sum rules. Using the symmetry arguments, some structure independent relations among different correlation functions are obtained. It is shown that all possible transitions are described by only one invariant function, whose explicit expression is structure dependent.

  3. Holographic dark energy with varying gravitational constant in Ho?ava-Lifshitz cosmology

    SciTech Connect (OSTI)

    Setare, M.R.; Jamil, Mubasher E-mail: mjamil@camp.nust.edu.pk

    2010-02-01

    We investigate the holographic dark energy scenario with a varying gravitational constant in a flat background in the context of Ho?ava-Lifshitz gravity. We extract the exact differential equation determining the evolution of the dark energy density parameter, which includes G variation term. Also we discuss a cosmological implication of our work by evaluating the dark energy equation of state for low redshifts containing varying G corrections.

  4. Measurement of piezoelectric constants of lanthanum-gallium tantalate crystal by X-ray diffraction methods

    SciTech Connect (OSTI)

    Blagov, A. E.; Marchenkov, N. V. Pisarevsky, Yu. V.; Prosekov, P. A.; Kovalchuk, M. V.

    2013-01-15

    A method for measuring piezoelectric constants of crystals of intermediate systems by X-ray quasi-multiple-wave diffraction is proposed and implemented. This technique makes it possible to determine the piezoelectric coefficient by measuring variations in the lattice parameter under an external electric field. This method has been approved, its potential is evaluated, and a comparison with high-resolution X-ray diffraction data is performed.

  5. Layered Copper-Based Electrode for High-Dielectric Constant Oxide

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

    Thin-Film-Based Devices | Argonne National Laboratory Copper-Based Electrode for High-Dielectric Constant Oxide Thin-Film-Based Devices Technology available for licenisng: A multilayer thin-film device containing copper layers protected by amorphous TiAl oxide and devices incorporating TiAl. Offers high conductivity and protection against oxidation Low-cost process PDF icon copper_based_electrode

  6. Quantization of a particle on a two-dimensional manifold of constant curvature

    SciTech Connect (OSTI)

    Bracken, Paul [Department of Mathematics, University of Texas, Edinburg, Texas 78540 (United States)

    2014-10-15

    The formulation of quantum mechanics on spaces of constant curvature is studied. It is shown how a transition from a classical system to the quantum case can be accomplished by the quantization of the Noether momenta. These can be determined by means of Lie differentiation of the metric which defines the manifold. For the metric examined here, it is found that the resulting Schrdinger equation is separable and the spectrum and eigenfunctions can be investigated in detail.

  7. Limiting electron beam current for cyclic induction acceleration in a constant guide field

    SciTech Connect (OSTI)

    Kanunnikov, V.N.

    1982-09-01

    Theoretical relations are derived for the limiting beam current in a cyclic induction accelerator (CIA) with a constant guide field. The calculations are in agreement with the available experimental data. It is shown that the limiting average beam current in a CIA is of the order of 100 microamperes, i.e., the level attained in microtrons and linear accelerators. The CIA may find industrial applications.

  8. HYPERFINE STRUCTURE CONSTANTS OF ENERGETICALLY HIGH-LYING LEVELS OF ODD PARITY OF ATOMIC VANADIUM

    SciTech Connect (OSTI)

    Güzelçimen, F.; Yapıcı, B.; Demir, G.; Er, A.; Öztürk, I. K.; Başar, Gö.; Kröger, S.; Tamanis, M.; Ferber, R.; Docenko, D.; Başar, Gü. E-mail: sophie.kroeger@htw-berlin.de

    2014-09-01

    High-resolution Fourier transform spectra of a vanadium-argon plasma have been recorded in the wavelength range of 365-670 nm (15,000-27,400 cm{sup –1}). Optical bandpass filters were used in the experimental setup to enhance the sensitivity of the Fourier transform spectrometer. In total, 138 atomic vanadium spectral lines showing resolved or partially resolved hyperfine structure have been analyzed to determine the magnetic dipole hyperfine structure constants A of the involved energy levels. One of the investigated lines has not been previously classified. As a result, the magnetic dipole hyperfine structure constants A for 90 energy levels are presented: 35 of them belong to the configuration 3d {sup 3}4s4p and 55 to the configuration 3d {sup 4}4p. Of these 90 constants, 67 have been determined for the first time, with 23 corresponding to the configuration 3d {sup 3}4s4p and 44 to 3d {sup 4}4p.

  9. Discrete accidental symmetry for a particle in a constant magnetic field on a torus

    SciTech Connect (OSTI)

    Al-Hashimi, M.H. Wiese, U.-J.

    2009-02-15

    A classical particle in a constant magnetic field undergoes cyclotron motion on a circular orbit. At the quantum level, the fact that all classical orbits are closed gives rise to degeneracies in the spectrum. It is well-known that the spectrum of a charged particle in a constant magnetic field consists of infinitely degenerate Landau levels. Just as for the 1/r and r{sup 2} potentials, one thus expects some hidden accidental symmetry, in this case with infinite-dimensional representations. Indeed, the position of the center of the cyclotron circle plays the role of a Runge-Lenz vector. After identifying the corresponding accidental symmetry algebra, we re-analyze the system in a finite periodic volume. Interestingly, similar to the quantum mechanical breaking of CP invariance due to the {theta}-vacuum angle in non-Abelian gauge theories, quantum effects due to two self-adjoint extension parameters {theta}{sub x} and {theta}{sub y} explicitly break the continuous translation invariance of the classical theory. This reduces the symmetry to a discrete magnetic translation group and leads to finite degeneracy. Similar to a particle moving on a cone, a particle in a constant magnetic field shows a very peculiar realization of accidental symmetry in quantum mechanics.

  10. Gyromagnetic factors and atomic clock constraints on the variation of fundamental constants

    SciTech Connect (OSTI)

    Luo Feng; Olive, Keith A.; Uzan, Jean-Philippe

    2011-11-01

    We consider the effect of the coupled variations of fundamental constants on the nucleon magnetic moment. The nucleon g-factor enters into the interpretation of the measurements of variations in the fine-structure constant, {alpha}, in both the laboratory (through atomic clock measurements) and in astrophysical systems (e.g. through measurements of the 21 cm transitions). A null result can be translated into a limit on the variation of a set of fundamental constants, that is usually reduced to {alpha}. However, in specific models, particularly unification models, changes in {alpha} are always accompanied by corresponding changes in other fundamental quantities such as the QCD scale, {Lambda}{sub QCD}. This work tracks the changes in the nucleon g-factors induced from changes in {Lambda}{sub QCD} and the light quark masses. In principle, these coupled variations can improve the bounds on the variation of {alpha} by an order of magnitude from existing atomic clock and astrophysical measurements. Unfortunately, the calculation of the dependence of g-factors on fundamental parameters is notoriously model-dependent.

  11. Self-Organizing Maps and Parton Distribution Functions

    SciTech Connect (OSTI)

    K. Holcomb, Simonetta Liuti, D. Z. Perry

    2011-05-01

    We present a new method to extract parton distribution functions from high energy experimental data based on a specific type of neural networks, the Self-Organizing Maps. We illustrate the features of our new procedure that are particularly useful for an anaysis directed at extracting generalized parton distributions from data. We show quantitative results of our initial analysis of the parton distribution functions from inclusive deep inelastic scattering.

  12. Distributed Wind Market Applications

    SciTech Connect (OSTI)

    Forsyth, T.; Baring-Gould, I.

    2007-11-01

    Distributed wind energy systems provide clean, renewable power for on-site use and help relieve pressure on the power grid while providing jobs and contributing to energy security for homes, farms, schools, factories, private and public facilities, distribution utilities, and remote locations. America pioneered small wind technology in the 1920s, and it is the only renewable energy industry segment that the United States still dominates in technology, manufacturing, and world market share. The series of analyses covered by this report were conducted to assess some of the most likely ways that advanced wind turbines could be utilized apart from large, central station power systems. Each chapter represents a final report on specific market segments written by leading experts in this field. As such, this document does not speak with one voice but rather a compendium of different perspectives, which are documented from a variety of people in the U.S. distributed wind field.

  13. Distributed data transmitter

    DOE Patents [OSTI]

    Brown, Kenneth Dewayne; Dunson, David

    2008-06-03

    A distributed data transmitter (DTXR) which is an adaptive data communication microwave transmitter having a distributable architecture of modular components, and which incorporates both digital and microwave technology to provide substantial improvements in physical and operational flexibility. The DTXR has application in, for example, remote data acquisition involving the transmission of telemetry data across a wireless link, wherein the DTXR is integrated into and utilizes available space within a system (e.g., a flight vehicle). In a preferred embodiment, the DTXR broadly comprises a plurality of input interfaces; a data modulator; a power amplifier; and a power converter, all of which are modularly separate and distinct so as to be substantially independently physically distributable and positionable throughout the system wherever sufficient space is available.

  14. Distributed data transmitter

    DOE Patents [OSTI]

    Brown, Kenneth Dewayne; Dunson, David

    2006-08-08

    A distributed data transmitter (DTXR) which is an adaptive data communication microwave transmitter having a distributable architecture of modular components, and which incorporates both digital and microwave technology to provide substantial improvements in physical and operational flexibility. The DTXR has application in, for example, remote data acquisition involving the transmission of telemetry data across a wireless link, wherein the DTXR is integrated into and utilizes available space within a system (e.g., a flight vehicle). In a preferred embodiment, the DTXR broadly comprises a plurality of input interfaces; a data modulator; a power amplifier; and a power converter, all of which are modularly separate and distinct so as to be substantially independently physically distributable and positionable throughout the system wherever sufficient space is available.

  15. Distributed Sensors Simulator

    Energy Science and Technology Software Center (OSTI)

    2003-08-30

    The Distributed Sensors Simulator (DSS) is an infrastructure that allows the user to debug and test software for distributed sensor networks without the commitment inherent in using hardware. The flexibility of DSS allows developers and researchers to investigate topological, phenomenological, networking, robustness, and scaling issues; explore arbitrary algorithms for DSNs; and is particularly useful as a proof-of-concept tool. The user provides data on node location and specifications, defines event phenomena, and plugs in the application(s)more » to run. DSS in turn provides the virtual environmental embedding — but exposed to the user like no true embedding could ever be.« less

  16. Distributed Wind | Department of Energy

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

    Distributed Wind Distributed Wind The Wind Program's activities in wind technologies in distributed applications-or distributed wind-address the performance and reliability challenges associated with smaller turbines by focusing on technology development, testing, certification, and manufacturing. What is Distributed Wind? Photo of a turbine behind a school. The Wind Program defines distributed wind in terms of technology application, based on a wind plant's location relative to end-use and

  17. Annual Coal Distribution Tables

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

    and Foreign Distribution of U.S. Coal by State of Origin, 2001 State Region Domestic Foreign Total Alabama 14,828 4,508 19,336 Alaska 825 698 1,524 Arizona 13,143 - 13,143...

  18. Distribution Category: Water R

    Office of Scientific and Technical Information (OSTI)

    Distribution Category: Water R e a c t o r Safety- R e s e a r c h - - A n a l y s i s ... 8 10 I TOTAL VOLUMETRIC FLUX, ms Fig. 9. Fully Developed Air-Water Flow Data.30 ANL Neg. ...

  19. Aerosol distribution apparatus

    DOE Patents [OSTI]

    Hanson, W.D.

    An apparatus for uniformly distributing an aerosol to a plurality of filters mounted in a plenum, wherein the aerosol and air are forced through a manifold system by means of a jet pump and released into the plenum through orifices in the manifold. The apparatus allows for the simultaneous aerosol-testing of all the filters in the plenum.

  20. Two Photon Distribution Amplitudes

    SciTech Connect (OSTI)

    El Beiyad, M.; Pire, B.; Szymanowski, L.; Wallon, S.

    2008-08-29

    The factorization of the amplitude of the process {gamma}*{gamma}{yields}{gamma}{gamma} in the low energy and high photon virtuality region is demonstrated at the Born order and in the leading logarithmic approximation. The leading order two photon (generalized) distribution amplitudes exhibit a characteristic ln Q{sup 2} behaviour and obey new inhomogeneous evolution equations.

  1. Low Latency Messages on Distributed Memory Multiprocessors

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

    Rosing, Matt; Saltz, Joel

    1995-01-01

    This article describes many of the issues in developing an efficient interface for communication on distributed memory machines. Although the hardware component of message latency is less than 1 ws on many distributed memory machines, the software latency associated with sending and receiving typed messages is on the order of 50 μs. The reason for this imbalance is that the software interface does not match the hardware. By changing the interface to match the hardware more closely, applications with fine grained communication can be put on these machines. This article describes several tests performed and many of the issues involvedmore » in supporting low latency messages on distributed memory machines.« less

  2. Stress corrosion cracking of Alloy 600 using the constant strain rate test

    SciTech Connect (OSTI)

    Bulischeck, T.S.; Van Rooyen, D.

    1981-10-01

    Nuclear grade production tubing of Alloy 600 was evaluated for stress corrosion cracking (SCC) susceptibility in high purity water at 365, 345, 325, and 290 C. Reverse tube U-bend specimens provided crack initiation data and constant extension rate tests were employed to determine the crack velocities experienced in th crack propagation stage. Initial results indicate that a linear extrapolation of data received from high temperature tests can be used to predict the service life of steam generator tubing that has been plastically deformed or is continually deforming by ''denting.''

  3. Sensitivity of ultracold-atom scattering experiments to variation of the fine-structure constant

    SciTech Connect (OSTI)

    Borschevsky, A.; Beloy, K.; Flambaum, V. V.; Schwerdtfeger, P.

    2011-05-15

    We present numerical calculations for cesium and mercury to estimate the sensitivity of the scattering length to the variation of the fine-structure constant {alpha}. The method used follows the ideas of Chin and Flambaum [Phys. Rev. Lett. 96, 230801 (2006)], where the sensitivity to the variation of the electron-to-proton mass ratio {beta} was considered. We demonstrate that for heavy systems, the sensitivity to the variation of {alpha} is of the same order of magnitude as to the variation of {beta}. Near narrow Feshbach resonances, the enhancement of the sensitivity may exceed nine orders of magnitude.

  4. Noninvasive valve monitor using constant magnetic and/or DC electromagnetic field

    DOE Patents [OSTI]

    Casada, D.A.; Haynes, H.D.

    1993-08-17

    One or more sources of steady magnetic field are carefully located on the outside of a valve body. The constant magnetic field is transmitted into the valve body and valve internals. A magnetic field detector carefully located on the outside of the valve body detects the intensity of the magnetic field at its location. As the position of a valve internal part is changed, there is an alteration in the magnetic field in the valve, and a consequent change in the detected magnetic field. Changes in the detected signal provide an indication of the position and motion of the valve internals.

  5. Noninvasive valve monitor using constant magnetic and/or DC electromagnetic field

    DOE Patents [OSTI]

    Casada, Donald A.; Haynes, Howard D.

    1993-01-01

    One or more sources of steady magnetic field are carefully located on the outside of a valve body. The constant magnetic field is transmitted into the valve body and valve internals. A magnetic field detector carefully located on the outside of the valve body detects the intensity of the magnetic field at its location. As the position of a valve internal part is changed, there is an alteration in the magnetic field in the valve, and a consequent change in the detected magnetic field. Changes in the detected signal provide an indication of the position and motion of the valve internals.

  6. Variation of stability constants of thorium and uranium oxalate complexes with ionic strength

    SciTech Connect (OSTI)

    Erten, H.N; Mohammed, A.K.; Choppin, G.R.

    1993-12-31

    Extraction of Th(IV) and UO{sub 2}{sup 2+} by a solution of TTA and HDEHP, respectively, in toluene was used to obtain stability constants of their oxalate complexes in 1, 3, 5, 7 and 9 M ionic strength (NaClO{sub 2}) solutions. The complexes formed were the MOx, MHOx, MOx{sub 2} and M(HOx){sub 2} (M = Th, UO{sub 2}) species. The values were analyzed by the Specific Interaction Theory and agreed to I {le} 3 M but required an additional term for fitting at I > 3 M.

  7. SU-E-T-421: Feasibility Study of Volumetric Modulated Arc Therapy with Constant Dose Rate for Endometrial Cancer

    SciTech Connect (OSTI)

    Yang, R; Wang, J

    2014-06-01

    Purpose: To investigate the feasibility, efficiency, and delivery accuracy of volumetric modulated arc therapy with constant dose rate (VMAT-CDR) for whole-pelvic radiotherapy (WPRT) of endometrial cancer. Methods: The nine-Field intensity-modulated radiotherapy (IMRT), VMAT with variable dose-rate (VMAT-VDR), and VMAT-CDR plans were created for 9 patients with endometrial cancer undergoing WPRT. The dose distribution of planning target volume (PTV), organs at risk (OARs), and normal tissue (NT) were compared. The monitor units (MUs) and treatment delivery time were also evaluated. For each VMAT-CDR plan, a dry Run was performed to assess the dosimetric accuracy with MatriXX from IBA. Results: Compared with IMRT, the VMAT-CDR plans delivered a slightly greater V20 of the bowel, bladder, pelvis bone, and NT, but significantly decreased the dose to the high-dose region of the rectum and pelvis bone. The MUs Decreased from 1105 with IMRT to 628 with VMAT-CDR. The delivery time also decreased from 9.5 to 3.2 minutes. The average gamma pass rate was 95.6% at the 3%/3 mm criteria with MatriXX pretreatment verification for 9 patients. Conclusion: VMAT-CDR can achieve comparable plan quality with significant shorter delivery time and smaller number of MUs compared with IMRT for patients with endometrial cancer undergoing WPRT. It can be accurately delivered and be an alternative to IMRT on the linear accelerator without VDR capability. This work is supported by the grant project, National Natural; Science Foundation of China (No. 81071237)

  8. Near equilibrium distributions for beams with space charge in linear and nonlinear periodic focusing systems

    SciTech Connect (OSTI)

    Sonnad, Kiran G.; Cary, John R.

    2015-04-15

    A procedure to obtain a near equilibrium phase space distribution function has been derived for beams with space charge effects in a generalized periodic focusing transport channel. The method utilizes the Lie transform perturbation theory to canonically transform to slowly oscillating phase space coordinates. The procedure results in transforming the periodic focusing system to a constant focusing one, where equilibrium distributions can be found. Transforming back to the original phase space coordinates yields an equilibrium distribution function corresponding to a constant focusing system along with perturbations resulting from the periodicity in the focusing. Examples used here include linear and nonlinear alternating gradient focusing systems. It is shown that the nonlinear focusing components can be chosen such that the system is close to integrability. The equilibrium distribution functions are numerically calculated, and their properties associated with the corresponding focusing system are discussed.

  9. Multipartite secure state distribution

    SciTech Connect (OSTI)

    Duer, W.; Briegel, H.-J.; Calsamiglia, J.

    2005-04-01

    We introduce the distribution of a secret multipartite entangled state in a real-world scenario as a quantum primitive. We show that in the presence of noisy quantum channels (and noisy control operations), any state chosen from the set of two-colorable graph states (Calderbank-Shor-Steane codewords) can be created with high fidelity while it remains unknown to all parties. This is accomplished by either blind multipartite entanglement purification, which we introduce in this paper, or by multipartite entanglement purification of enlarged states, which offers advantages over an alternative scheme based on standard channel purification and teleportation. The parties are thus provided with a secret resource of their choice for distributed secure applications.

  10. Properly Understanding the Impacts of Distributed Resources on Distribution Systems

    SciTech Connect (OSTI)

    Rizy, D Tom; Li, Fangxing; Li, Huijuan; Adhikari, Sarina; Kueck, John D

    2010-01-01

    The subject paper discusses important impacts of distributed resources on distribution networks and feeders. These include capacity, line losses, voltage regulation, and central system support (such as volt/var via central generators and substation) as the number, placement and penetration levels of distributed resources are varied. Typically, the impacts of distributed resources on the distribution system are studied by using steady-state rather than dynamic analysis tools. However, the response time and transient impacts of both system equipment (such as substation/feeder capacitors) and distributed resources needs to be taken into account and only dynamic analysis will provide the full impact results. ORNL is wrapping up a study of distributed resources interconnected to a large distribution system considering the above variables. A report of the study and its results will be condensed into a paper for this panel session. The impact of distributed resources will vary as the penetration level reaches the capacity of the distribution feeder/system. The question is how high of a penetration of distributed resource can be accommodated on the distribution feeder/system without any major changes to system operation, design and protection. The impacts most surely will vary depending upon load composition, distribution and level. Also, it is expected that various placement of distributed resources will impact the distribution system differently.

  11. Lumen mass transfer in hollow-fiber membrane processes with constant external resistances

    SciTech Connect (OSTI)

    Qin, Y.; Cabral, J.M.S.

    1997-08-01

    Membrane processes have recently become an accepted unit operation for a wide variety of separations in industry and in environmental applications. Hollow-fiber membrane processes with a constant external resistance having a constant or variable shell concentration resulting from an operational mode of cocurrent or countercurrent are studied. By solving numerically the continuity mass-conservation equation with the corresponding boundary conditions, the lumen laminar mass-transfer coefficients for both cases are correlated. The correlations greatly improve the calculating accuracy of the overall mass-transfer coefficient and can be used to obtain the lumen mixed-cup concentration by an algebraic equation substituting the partial differential equation. A separation factor m{prime} is introduced to characterize the effect of the operational mode. Calculation results demonstrate that the lumen mass-transfer coefficient is independent of the real lumen and shell concentrations, but it is greatly influenced by m{prime}. The countercurrent mode, compared to the cocurrent mode, provides not only a higher mean driving force, but a higher lumen mass-transfer coefficient. This conclusion is novel and valid for the tube-shell heat or mass-transfer processes and is supported by the experimental data in the literature and the authors` gas membrane separation experiments.

  12. The cosmological constant: Plus CA change, plus C`est La Meme Chose

    SciTech Connect (OSTI)

    Frieman, J.A.

    1998-02-01

    Recent measurements of the cosmological parameters have renewed interest in the cosmological constant {Lambda}. I briefly review the current status of these measurements and the corresponding arguments for and against cosmological models with non-zero {Lambda}. I outline a scenario which attempts to incorporate non-zero vacuum energy into the framework of particle physics, based on an ultra-light pseudo-Nambu-Goldstone boson. With global spontaneous symmetry breaking scale f {approx_equal} 10{sup 18} GeV and explicit breaking scale comparable to MSW neutrino masses, M {approximately} 10{sup -3} eV, such a field, which acquires a mass M{sub {phi}} {approximately} M{sup 2}/f {approximately} H{sub 0}, would have become dynamical at recent epochs and currently dominate the energy density of the universe. The field acts as an effective cosmological constant for several expansion times and then relaxes into a condensate of coherent non-relativistic bosons. Such a model can reconcile dynamical estimates of the density parameter, {Omega}{sub m} {approximately} 0.2, with a spatially flat universe, and can yield an expansion age H{sub 0}t{sub 0} {approx_equal} 1 while remaining consistent with limits from gravitational lens statistics.

  13. Variation of lattice constant and cluster formation in GaAsBi

    SciTech Connect (OSTI)

    Puustinen, J.; Schramm, A.; Guina, M.; Wu, M.; Luna, E.; Laukkanen, P.; Laitinen, M.; Sajavaara, T.

    2013-12-28

    We investigate the structural properties of GaAsBi layers grown by molecular beam epitaxy on GaAs at substrate temperatures between 220315 C. Irrespective of the growth temperature, the structures exhibited similar Bi compositions, and good overall crystal quality as deduced from X-Ray diffraction measurements. After thermal annealing at temperatures as low as 500 C, the GaAsBi layers grown at the lowest temperatures exhibited a significant reduction of the lattice constant. The lattice variation was significantly larger for Bi-containing samples than for Bi-free low-temperature GaAs samples grown as a reference. Rutherford backscattering spectrometry gave no evidence of Bi diffusing out of the layer during annealing. However, dark-field and Z-contrast transmission electron microscopy analyses revealed the formation of GaAsBi clusters with a Bi content higher than in the surrounding matrix, as well as the presence of metallic As clusters. The apparent reduction of the lattice constant can be explained by a two-fold process: the diffusion of the excess As incorporated within As{sub Ga} antisites to As clusters, and the reduction of the Bi content in the GaAs matrix due to diffusion of Bi to GaAsBi clusters. Diffusion of both As and Bi are believed to be assisted by the native point defects, which are present in the low-temperature as-grown material.

  14. Femtosecond frequency comb measurement of absolute frequencies and hyperfine coupling constants in cesium vapor

    SciTech Connect (OSTI)

    Stalnaker, Jason E.; Mbele, Vela; Gerginov, Vladislav; Fortier, Tara M.; Diddams, Scott A.; Hollberg, Leo; Tanner, Carol E.

    2010-04-15

    We report measurements of absolute transition frequencies and hyperfine coupling constants for the 8S{sub 1/2}, 9S{sub 1/2}, 7D{sub 3/2}, and 7D{sub 5/2} states in {sup 133}Cs vapor. The stepwise excitation through either the 6P{sub 1/2} or 6P{sub 3/2} intermediate state is performed directly with broadband laser light from a stabilized femtosecond laser optical-frequency comb. The laser beam is split, counterpropagated, and focused into a room-temperature Cs vapor cell. The repetition rate of the frequency comb is scanned and we detect the fluorescence on the 7P{sub 1/2,3/2{yields}}6S{sub 1/2} branches of the decay of the excited states. The excitations to the different states are isolated by the introduction of narrow-bandwidth interference filters in the laser beam paths. Using a nonlinear least-squares method we find measurements of transition frequencies and hyperfine coupling constants that are in agreement with other recent measurements for the 8S state and provide improvement by 2 orders of magnitude over previously published results for the 9S and 7D states.

  15. Asymptotically (anti)-de Sitter solutions in Gauss-Bonnet gravity without a cosmological constant

    SciTech Connect (OSTI)

    Dehghani, M.H.

    2004-09-15

    In this paper I show that one can have asymptotically de Sitter, anti-de Sitter (AdS), and flat solutions in Gauss-Bonnet gravity without a cosmological constant term in field equations. First, I introduce static solutions whose three surfaces at fixed r and t have constant positive (k=1), negative (k=-1), or zero (k=0) curvature. I show that for k={+-}1 one can have asymptotically de Sitter, AdS, and flat spacetimes, while for the case of k=0, one has only asymptotically AdS solutions. Some of these solutions present naked singularities, while some others are black hole or topological black hole solutions. I also find that the geometrical mass of these five-dimensional spacetimes is m+2{alpha}|k|, which is different from the geometrical mass m of the solutions of Einstein gravity. This feature occurs only for the five-dimensional solutions, and is not repeated for the solutions of Gauss-Bonnet gravity in higher dimensions. Second, I add angular momentum to the static solutions with k=0, and introduce the asymptotically AdS charged rotating solutions of Gauss-Bonnet gravity. Finally, I introduce a class of solutions which yields an asymptotically AdS spacetime with a longitudinal magnetic field, which presents a naked singularity, and generalize it to the case of magnetic rotating solutions with two rotation parameters.

  16. Reduction of iron-oxide-carbon composites: part I. Estimation of the rate constants

    SciTech Connect (OSTI)

    Halder, S.; Fruehan, R.J.

    2008-12-15

    A new ironmaking concept using iron-oxide-carbon composite pellets has been proposed, which involves the combination of a rotary hearth furnace (RHF) and an iron bath smelter. This part of the research focuses on studying the two primary chemical kinetic steps. Efforts have been made to experimentally measure the kinetics of the carbon gasification by CO{sub 2} and wustite reduction by CO by isolating them from the influence of heat- and mass-transport steps. A combined reaction model was used to interpret the experimental data and determine the rate constants. Results showed that the reduction is likely to be influenced by the chemical kinetics of both carbon oxidation and wustite reduction at the temperatures of interest. Devolatilized wood-charcoal was observed to be a far more reactive form of carbon in comparison to coal-char. Sintering of the iron-oxide at the high temperatures of interest was found to exert a considerable influence on the reactivity of wustite by virtue of altering the internal pore surface area available for the reaction. Sintering was found to be predominant for highly porous oxides and less of an influence on the denser ores. It was found using an indirect measurement technique that the rate constants for wustite reduction were higher for the porous iron-oxide than dense hematite ore at higher temperatures (> 1423 K). Such an indirect mode of measurement was used to minimize the influence of sintering of the porous oxide at these temperatures.

  17. Constant-current charging supplies for the Advanced Photon Source (APS) linear accelerator modulators

    SciTech Connect (OSTI)

    Fuja, R.; Grelick, A.E.; Meyer, D.

    1997-06-01

    The APS linac beam energy must be stable to within {+-}1% to match the energy acceptance of the positron accumulator ring. The klystron pulse modulators must therefore provide a pulse-to-pulse repeatability of 0.1% in order for the beam to have the required energy stability. The modulators have had difficulty achieving the necessary repeatability since the pulse forming network (PFN) charging scheme does not include a deQing circuit. Several of the major charging circuit components are also less reliable than desired. In order to increase operating reliability and to improve pulse-to-pulse stability, it is planned to replace the high voltage power supplies in all modulators with constant-current power supplies. A new modulator charging supply that contains two EMI series 303 constant-current power supplies was constructed. Each of these EMI supplies delivers 1.5 A at up to 40 kV. One supply is sufficient for linac operation at up to 45 Hz, and two supplies in parallel enable linac operation at the nominal rf repetition rate of 60 Hz. This paper discusses test results from the new modulator, and also describes the existing modulators and their performance limitations.

  18. Symmetric generalized binomial distributions

    SciTech Connect (OSTI)

    Bergeron, H.; Curado, E. M. F.; Instituto Nacional de Cincia e Tecnologia - Sistemas Complexos, Rua Xavier Sigaud 150, 22290-180 - Rio de Janeiro, RJ ; Gazeau, J. P.; APC, UMR 7164, Univ Paris Diderot, Sorbonne Paris Cit, 75205 Paris ; Rodrigues, Ligia M. C. S. E-mail: evaldo@cbpf.br E-mail: ligia@cbpf.br

    2013-12-15

    In two recent articles, we have examined a generalization of the binomial distribution associated with a sequence of positive numbers, involving asymmetric expressions of probabilities that break the symmetry win-loss. We present in this article another generalization (always associated with a sequence of positive numbers) that preserves the symmetry win-loss. This approach is also based on generating functions and presents constraints of non-negativeness, similar to those encountered in our previous articles.

  19. MEMORANDUM FOR DISTRIBUTION

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

    * Department of Energy Washington, DC 20585 December 20, 2007 MEMORANDUM FOR DISTRIBUTION FROM: MICHAEL W. OWEN /<f /c / DIRECTOR, OFFICE OF LEGACY MANAGEM.ENT SUBJECT: Compliance with Established Policies and Guidance for Contractor Work Force Restructuring As you know, the Office of Legacy Management (LM) is the Department's fical point for all work force restructuring actions. As a reminder of policies and guidance that should continue to be followed when implementing work force

  20. Computing Frontier: Distributed Computing

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

    Computing Frontier: Distributed Computing and Facility Infrastructures Conveners: Kenneth Bloom 1 , Richard Gerber 2 1 Department of Physics and Astronomy, University of Nebraska-Lincoln 2 National Energy Research Scientific Computing Center (NERSC), Lawrence Berkeley National Laboratory 1.1 Introduction The field of particle physics has become increasingly reliant on large-scale computing resources to address the challenges of analyzing large datasets, completing specialized computations and

  1. Distributed generation implementation guidelines

    SciTech Connect (OSTI)

    Guzy, L.; O`Sullivan, J.B.; Jacobs, K.; Major, W.

    1999-11-01

    The overall economics of a distributed generation project is based on cost elements which include: Equipment and financing, fuel, displaced electricity cost, operation and maintenance. Of critical importance is how the facility is managed, including adequate provision for a comprehensive operator training program. Proper equipment maintenance and fuel procurement policy will also lead to greater system availability and optimal system economics. Various utility tariffs are available which may be economically attractive, with an added benefit to the utility of providing a peak shaving resource during peak periods. Changing modes of operation of the distributed generation system may affect staff readiness, require retraining and could affect maintenance costs. The degree of control and oversight that is provided during a project`s implementation and construction phases will impact subsequent maintenance and operating costs. The long term effect of siting impacts, such as building facades that restrict turbine inlet airflow will affect subsequent operations and require supplemental maintenance action. It is possible to site a variety of distributed generation technologies in settings which vary from urban to remote unattended locations with successful results from both an economic and operational perspective.

  2. Diagnosing delivery problems in the White House Information Distribution System

    SciTech Connect (OSTI)

    Nahabedian, M.; Shrobe, H.

    1996-12-31

    As part of a collaboration with the White House Office of Media Affairs, members of the MIT Artificial Intelligence Laboratory designed a system, called COMLINK, which distributes a daily stream of documents released by the Office of Media Affairs. Approximately 4000 direct subscribers receive information from this service but more than 100,000 people receive the information through redistribution channels. The information is distributed via Email and the World Wide Web. In such a large scale distribution scheme, there is a constant problem of subscriptions becoming invalid because the user`s Email account has terminated. This causes a backwash of hundreds of {open_quotes}bounced mail{close_quotes} messages per day which must be processed by the operators of the COMLINK system. To manage this annoying but necessary task, an expert system named BMES was developed to diagnose the failures of information delivery.

  3. Analytic Evolution of Singular Distribution Amplitudes in QCD

    SciTech Connect (OSTI)

    Radyushkin, Anatoly V.; Tandogan Kunkel, Asli

    2014-03-01

    We describe a method of analytic evolution of distribution amplitudes (DA) that have singularities, such as non-zero values at the end-points of the support region, jumps at some points inside the support region and cusps. We illustrate the method by applying it to the evolution of a flat (constant) DA, anti-symmetric at DA and then use it for evolution of the two-photon generalized distribution amplitude. Our approach has advantages over the standard method of expansion in Gegenbauer polynomials, which requires infinite number of terms in order to accurately reproduce functions in the vicinity of singular points, and over a straightforward iteration of an initial distribution with evolution kernel. The latter produces logarithmically divergent terms at each iteration, while in our method the logarithmic singularities are summed from the start, which immediately produces a continuous curve, with only one or two iterations needed afterwards in order to get rather precise results.

  4. Lattice constant grading in the Al.sub.y Ga.sub.1-y As.sub.1-x Sb.sub.x alloy system

    DOE Patents [OSTI]

    Moon, Ronald L.

    1980-01-01

    Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5 .mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photolvoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of growing layer.

  5. Lattice constant grading in the Al.sub.y Ca.sub.1-y As.sub.1-x Sb.sub.x alloy system

    DOE Patents [OSTI]

    Moon, Ronald L.

    1981-01-01

    Liquid phase epitaxy is employed to grow a lattice matched layer of GaAsSb on GaAs substrates through the compositional intermediary of the III-V alloy system AlGaAsSb which acts as a grading layer. The Al constituent reaches a peak atomic concentration of about 6% within the first 2.5.mu.m of the transition layer, then decreases smoothly to about 1% to obtain a lattice constant of 5.74 A. In the same interval the equilibrium concentration of Sb smoothly increases from 0 to about 9 atomic percent to form a surface on which a GaAsSb layer having the desired energy bandgap of 1.1 ev for one junction of an optimized dual junction photovoltaic device. The liquid phase epitaxy is accomplished with a step cooling procedure whereby dislocation defects are more uniformly distributed over the surface of the growing layer.

  6. Sondex PHE-Type SL140-TM-EE-190 | Open Energy Information

    Open Energy Info (EERE)

    PHE-Type SL140TM-EE-190 Distributed Generation Purpose Domestic hot water, Space heat, HVAC reheat Retrieved from "http:en.openei.orgwindex.php?titleSondexPHE-TypeSL140-TM-...

  7. Sondex PHE-Type SL140-TM-EE-150 | Open Energy Information

    Open Energy Info (EERE)

    PHE-Type SL140TM-EE-150 Distributed Generation Purpose Domestic hot water, Space heat, HVAC reheat Retrieved from "http:en.openei.orgwindex.php?titleSondexPHE-TypeSL140-TM-...

  8. GASIFICATION FOR DISTRIBUTED GENERATION

    SciTech Connect (OSTI)

    Ronald C. Timpe; Michael D. Mann; Darren D. Schmidt

    2000-05-01

    A recent emphasis in gasification technology development has been directed toward reduced-scale gasifier systems for distributed generation at remote sites. The domestic distributed power generation market over the next decade is expected to be 5-6 gigawatts per year. The global increase is expected at 20 gigawatts over the next decade. The economics of gasification for distributed power generation are significantly improved when fuel transport is minimized. Until recently, gasification technology has been synonymous with coal conversion. Presently, however, interest centers on providing clean-burning fuel to remote sites that are not necessarily near coal supplies but have sufficient alternative carbonaceous material to feed a small gasifier. Gasifiers up to 50 MW are of current interest, with emphasis on those of 5-MW generating capacity. Internal combustion engines offer a more robust system for utilizing the fuel gas, while fuel cells and microturbines offer higher electric conversion efficiencies. The initial focus of this multiyear effort was on internal combustion engines and microturbines as more realistic near-term options for distributed generation. In this project, we studied emerging gasification technologies that can provide gas from regionally available feedstock as fuel to power generators under 30 MW in a distributed generation setting. Larger-scale gasification, primarily coal-fed, has been used commercially for more than 50 years to produce clean synthesis gas for the refining, chemical, and power industries. Commercial-scale gasification activities are under way at 113 sites in 22 countries in North and South America, Europe, Asia, Africa, and Australia, according to the Gasification Technologies Council. Gasification studies were carried out on alfalfa, black liquor (a high-sodium waste from the pulp industry), cow manure, and willow on the laboratory scale and on alfalfa, black liquor, and willow on the bench scale. Initial parametric tests

  9. Spark Distributed Analytic Framework

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

    Apache Spark Spark Distributed Analytic Framework Description and Overview Apache Spark(tm) is a fast and general engine for large-scale data processing. How to Use Spark Because of its high memory and I/O bandwidth requirements, we recommend you run your spark jobs on Cori. Follow the steps below to use spark, note that the order of the commands matters. DO NOT load the spark module until you are inside a batch job. Interactive mode Submit an interactive batch job with at least 2 nodes: salloc

  10. Distributed Optimization System

    DOE Patents [OSTI]

    Hurtado, John E.; Dohrmann, Clark R.; Robinett, III, Rush D.

    2004-11-30

    A search system and method for controlling multiple agents to optimize an objective using distributed sensing and cooperative control. The search agent can be one or more physical agents, such as a robot, and can be software agents for searching cyberspace. The objective can be: chemical sources, temperature sources, radiation sources, light sources, evaders, trespassers, explosive sources, time dependent sources, time independent sources, function surfaces, maximization points, minimization points, and optimal control of a system such as a communication system, an economy, a crane, and a multi-processor computer.

  11. Hard x-ray nanofocusing by refractive lenses of constant thickness

    SciTech Connect (OSTI)

    Seiboth, F. Scholz, M.; Patommel, J.; Hoppe, R.; Wittwer, F.; Reinhardt, J.; Seidel, J.; Knaut, M.; Jahn, A.; Richter, K.; Bartha, J. W.; Falkenberg, G.; Schroer, C. G.

    2014-09-29

    In order to focus light or x rays, the thickness of a refractive lens is typically varied over its aperture. Here, we present a refractive x-ray lens made of lamellae of constant thickness, the refractive lamellar lens. Refractive power is created by a specific bending of the lamellae rather than by a concave lens profile. This very special design has the technological advantage that materials like sapphire or diamond can be used to make lenses by coating techniques. A first lens prototype focused x rays with a photon energy E = 15.25 keV to a lateral beam size of 164 nm × 296 nm full width at half maximum.

  12. Decay Constants $f_B$ and $f_{B_s}$ from HISQ Simulations

    SciTech Connect (OSTI)

    Bazavov, A.; et al.

    2015-11-06

    We give a progress report on a project aimed at a high-precision calculation of the decay constants $f_B$ and $f_{B_s}$ from simulations with HISQ heavy and light valence and sea quarks. Calculations are carried out with several heavy valence-quark masses on ensembles with 2+1+1 flavors of HISQ sea quarks at five lattice spacings and several light sea-quark mass ratios $m_{ud}/m_s$, including approximately physical sea-quark masses. This range of parameters provides excellent control of the continuum limit and of heavy-quark discretization errors. We present a preliminary error budget with projected uncertainties of 2.2~MeV and 1.5~MeV for $f_B$ and $f_{B_s}$, respectively.

  13. GaAs high temperature optical constants and application to optical monitoring within the MOVPE environment

    SciTech Connect (OSTI)

    Allwood, D.A.; Klipstein, P.C.; Mason, N.J.; Nicholas, R.J.; Walker, P.J.

    2000-01-01

    The real and imaginary components of the GaAs refractive index at temperatures between 20--700 C have been obtained. Measurements were made by comparing the variable angle reflectivity of p-polarized and s-polarized 633 nm wavelength light from a deoxidized GaAs surface. By using these temperature-dependent optical constants for GaAs, modeling has allowed the behavior of surface photoabsorption (SPA) signals with temperature and oxide layers present to be predicted for different angles of incidence. The experimentally observed SPA signals during deoxidization of GaAs show strong qualitative agreement with these calculations at each of the angles of incidence considered. The measurement of data and application to modeling provides a platform for the measurement of temperature-dependent optical data for other III-V materials and for the investigation of deoxidation mechanisms.

  14. Improved Measurement of the Positive-Muon Lifetime and Determination of the Fermi Constant

    SciTech Connect (OSTI)

    Chitwood, D. B.; Clayton, S. M.; Crnkovic, J.; Debevec, P. T.; Hertzog, D. W.; Kammel, P.; Kiburg, B.; Kunkle, J.; McNabb, R.; Mulhauser, F.; Oezben, C. S.; Polly, C. C.; Webber, D. M.; Winter, P.; Banks, T. I.; Crowe, K. M.; Lauss, B.; Barnes, M. J.; Wait, G. D.; Battu, S.

    2007-07-20

    The mean life of the positive muon has been measured to a precision of 11 ppm using a low-energy, pulsed muon beam stopped in a ferromagnetic target, which was surrounded by a scintillator detector array. The result, {tau}{sub {mu}}=2.197 013(24) {mu}s, is in excellent agreement with the previous world average. The new world average {tau}{sub {mu}}=2.197 019(21) {mu}s determines the Fermi constant G{sub F}=1.166 371(6)x10{sup -5} GeV{sup -2} (5 ppm). Additionally, the precision measurement of the positive-muon lifetime is needed to determine the nucleon pseudoscalar coupling g{sub P}.

  15. Running coupling constant from lattice studies of gluon and ghost propagators

    SciTech Connect (OSTI)

    Cucchieri, A.; Mendes, T.

    2004-12-02

    We present a numerical study of the running coupling constant in four-dimensional pure-SU(2) lattice gauge theory. The running coupling is evaluated by fitting data for the gluon and ghost propagators in minimal Landau gauge. Following Refs. [1, 2], the fitting formulae are obtained by a simultaneous integration of the {beta} function and of a function coinciding with the anomalous dimension of the propagator in the momentum subtraction scheme. We consider these formulae at three and four loops. The fitting method works well, especially for the ghost case, for which statistical error and hyper-cubic effects are very small. Our present result for {lambda}MS is 200{sub -40}{sup +60} MeV, where the error is purely systematic. We are currently extending this analysis to five loops in order to reduce this systematic error.

  16. Time constant of defect relaxation in ion-irradiated 3C-SiC

    SciTech Connect (OSTI)

    Wallace, J. B.; Bayu Aji, L. B.; Kucheyev, S. O.; Shao, L.

    2015-05-18

    Above room temperature, the buildup of radiation damage in SiC is a dynamic process governed by the mobility and interaction of ballistically generated point defects. Here, we study the dynamics of radiation defects in 3C-SiC bombarded at 100 °C with 500 keV Ar ions, with the total ion dose split into a train of equal pulses. Damage–depth profiles are measured by ion channeling for a series of samples irradiated under identical conditions except for different durations of the passive part of the beam cycle. Results reveal an effective defect relaxation time constant of ∼3 ms (for second order kinetics) and a dynamic annealing efficiency of ∼40% for defects in both Si and C sublattices. This demonstrates a crucial role of dynamic annealing at elevated temperatures and provides evidence of the strong coupling of defect accumulation processes in the two sublattices of 3C-SiC.

  17. Effects of swirl-flow on flame propagation in a constant-volume vessel

    SciTech Connect (OSTI)

    Cai, P.; Watanabe, Kazunori; Obara, Tetsuro; Yoshihashi, Teruo; Ohyagi, Shigeharu

    1999-07-01

    Flame propagation in a closed vessel is one of the fundamental topics in the combustion science and technology. This problem has been studied mostly for application to engine combustion because the combustion processes in a premixed spark ignition engine are well simulated by those processes in a constant-volume combustion chamber. One of the most important objective to study this phenomena is to elucidate the combustion phenomena to increase the thermal efficiency of engine by enhancing the combustion process. In real engines, a number of technical methods such as swirl, tumble, squish and jet flows ere developed to shorten a burning time. All of these methods make use of flows in the combustion chamber. The fundamental problem is then to elucidate a mechanism of reduction of the burning time by the flows and their turbulence. In the present work, experiments were conducted to investigate the effects of swirl-flow on the flame propagation in a disc-shaped constant-volume vessel of 100 mm in diameter and 30 mm in depth. Figure A-1 shows a schematic of the apparatus. Gaseous mixtures used were methane diluted with air at an atmospheric pressure, and their equivalence ratios were varied as a parameter. Ignition timing was varied to change the velocity of swirling flow before the flame propagation. As results, a burning time was found to be decreased as the swirling flow increased and a maximum pressure was increased as the velocity increased as a total heat loss decreased. Flame front structures were clearly observed by the instantaneous schlieren photography.

  18. PULSE AMPLITUDE DISTRIBUTION RECORDER

    DOE Patents [OSTI]

    Cowper, G.

    1958-08-12

    A device is described for automatica1ly recording pulse annplitude distribution received from a counter. The novelty of the device consists of the over-all arrangement of conventional circuit elements to provide an easy to read permanent record of the pulse amplitude distribution during a certain time period. In the device a pulse analyzer separates the pulses according to annplitude into several channels. A scaler in each channel counts the pulses and operates a pen marker positioned over a drivable recorder sheet. Since the scalers in each channel have the sanne capacity, the control circuitry permits counting of the incoming pulses until one scaler reaches capacity, whereupon the input is removed and an internal oscillator supplies the necessary pulses to fill up the other scalers. Movement of the chart sheet is initiated wben the first scaler reaches capacity to thereby give a series of marks at spacings proportional to the time required to fill the remaining scalers, and accessory equipment marks calibration points on the recorder sheet to facilitate direct reading of the number of external pulses supplied to each scaler.

  19. Laboratory evaluation of mechanical properties of rock using an automated triaxial compression test with a constant mean stress criterion

    SciTech Connect (OSTI)

    Mellegard, K.D.; Pfeifle, T.W.

    1999-07-01

    A computerized, servohydraulic test system has been used in the laboratory to perform axisymmetric, triaxial compression tests on natural rock salt using a load path that maintains constant mean stress. The constant mean stress test protocol illustrates that modern test systems allow a nonstandard load path which can focus on a particular aspect of rock characterization; namely, the onset of dilation. Included are discussions of how the constant mean stress test could be used to investigate material anisotropy and determine elastic moduli. The results from the constant mean stress tests are compared to test results from a traditional test method. The paper also addresses system calibration concerns and the effects of pressure changes on the direct-contact extensometers used to measure strain.

  20. Multiple-type solutions for multipole interface solitons in thermal nonlinear media

    SciTech Connect (OSTI)

    Ma Xuekai; Yang Zhenjun; Lu Daquan; Hu Wei

    2011-09-15

    We address the existence of multipole interface solitons in one-dimensional thermal nonlinear media with a step in the linear refractive index at the sample center. It is found that there exist two types of solutions for tripole and quadrupole interface solitons. The two types of interface solitons have different profiles, beam widths, mass centers, and stability regions. For a given propagation constant, only one type of interface soliton is proved to be stable, while the other type can also survive over a long distance. In addition, three types of solutions for fifth-order interface solitons are found.

  1. Distributed charging of electrical assets

    DOE Patents [OSTI]

    Ghosh, Soumyadip; Phan, Dung; Sharma, Mayank; Wu, Chai Wah; Xiong, Jinjun

    2016-02-16

    The present disclosure relates generally to the field of distributed charging of electrical assets. In various examples, distributed charging of electrical assets may be implemented in the form of systems, methods and/or algorithms.

  2. Distributed road assessment system

    DOE Patents [OSTI]

    Beer, N. Reginald; Paglieroni, David W

    2014-03-25

    A system that detects damage on or below the surface of a paved structure or pavement is provided. A distributed road assessment system includes road assessment pods and a road assessment server. Each road assessment pod includes a ground-penetrating radar antenna array and a detection system that detects road damage from the return signals as the vehicle on which the pod is mounted travels down a road. Each road assessment pod transmits to the road assessment server occurrence information describing each occurrence of road damage that is newly detected on a current scan of a road. The road assessment server maintains a road damage database of occurrence information describing the previously detected occurrences of road damage. After the road assessment server receives occurrence information for newly detected occurrences of road damage for a portion of a road, the road assessment server determines which newly detected occurrences correspond to which previously detected occurrences of road damage.

  3. DISTRIBUTED AMPLIFIER INCORPORATING FEEDBACK

    DOE Patents [OSTI]

    Bell, P.R. Jr.

    1958-10-21

    An improved distributed amplifier system employing feedback for stabilization is presented. In accordance with the disclosed invention, a signal to be amplified is applled to one end of a suitable terminated grid transmission line. At intervals along the transmission line, the signal is fed to stable, resistance-capacitance coupled amplifiers incorporating feedback loops therein. The output current from each amplifier is passed through an additional tube to minimize the electrostatic capacitance between the tube elements of the last stage of the amplifier, and fed to appropriate points on an output transmission line, similar to the grid line, but terminated at the opposite (input) end. The output taken from the unterminated end of the plate transmission line is proportional to the input voltage impressed upon the grid line.

  4. GTT 2012 Distribution Workshop- Documents

    Broader source: Energy.gov [DOE]

    Use the links below to download documents from the GTT's Distribution Workshop, held September 24-26, 2012

  5. Interconnection of Distributed Energy Resources

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

    Interconnection of Distributed Energy Resources Delivered to: Transmission and Grid Basics for Tribal Economic and Energy Development Dave Narang Principal Engineer, NREL March 30, 2016 2 Discussion Topics * Distribution System Interconnections - Part 1 o Background o Distribution Systems Overview o Electric Utility Operations o Emerging Topics in Grid Integration o DOE Grid Modernization Initiative * Distribution System Interconnections - Part 2 o Permitting o Interconnection * Wrap up o

  6. Integrated Distribution Planning Concept Paper

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

    Distribution Planning Concept Paper www.irecusa.org A Proactive Approach for Accommodating High Penetrations of Distributed Generation Resources May 2013 Integrated Distribution Planning Concept Paper A Proactive Approach for Accommodating High Penetrations of Distributed Generation Resources Tim Lindl and Kevin Fox Interstate Renewable Energy Council, Inc. Abraham Ellis and Robert Broderick Sandia National Laboratories May 2013 IREC enables greater use of clean energy in a sustainable way by

  7. Structure–performance relationships for cantilever-type piezoelectric energy harvesters

    SciTech Connect (OSTI)

    Cho, Kyung-Hoon E-mail: spriya@vt.edu; Park, Hwi-Yeol; Heo, Jin S.; Priya, Shashank E-mail: spriya@vt.edu

    2014-05-28

    This study provides comprehensive analysis of the structure–performance relationships in cantilever-type piezoelectric energy harvesters. It provides full understanding of the effect of all the practical global control variables on the harvester performance. The control variables considered for the analysis were material parameters, areal and volumetric dimensions, and configuration of the inactive and active layers. Experimentally, the output power density of the harvester was maximum when the shape of the beam was close to a square for a constant bending stiffness and a fixed beam area. Through analytical modeling of the effective stiffness for the piezoelectric bimorph, the conditions for enhancing the bending stiffness within the same beam volume as that of a conventional bimorph were identified. The harvester configuration with beam aspect ratio of 0.86 utilizing distributed inactive layers exhibited an giant output power of 52.5 mW and power density of 28.5 mW cm{sup −3} at 30 Hz under 6.9 m s{sup −2} excitation. The analysis further indicates that the trend in the output power with varying damping ratio is dissimilar to that of the efficiency. In order to realize best performance, the harvester should be designed with respect to maximizing the magnitude of output power.

  8. Method of preparing mercury with an arbitrary isotopic distribution

    DOE Patents [OSTI]

    Grossman, Mark W.; George, William A.

    1986-01-01

    This invention provides for a process for preparing mercury with a predetermined, arbitrary, isotopic distribution. In one embodiment, different isotopic types of Hg.sub.2 Cl.sub.2, corresponding to the predetermined isotopic distribution of Hg desired, are placed in an electrolyte solution of HCl and H.sub.2 O. The resulting mercurous ions are then electrolytically plated onto a cathode wire producing mercury containing the predetermined isotopic distribution. In a similar fashion, Hg with a predetermined isotopic distribution is obtained from different isotopic types of HgO. In this embodiment, the HgO is dissolved in an electrolytic solution of glacial acetic acid and H.sub.2 O. The isotopic specific Hg is then electrolytically plated onto a cathode and then recovered.

  9. Method of preparing mercury with an arbitrary isotopic distribution

    DOE Patents [OSTI]

    Grossman, M.W.; George, W.A.

    1986-12-16

    This invention provides for a process for preparing mercury with a predetermined, arbitrary, isotopic distribution. In one embodiment, different isotopic types of Hg[sub 2]Cl[sub 2], corresponding to the predetermined isotopic distribution of Hg desired, are placed in an electrolyte solution of HCl and H[sub 2]O. The resulting mercurous ions are then electrolytically plated onto a cathode wire producing mercury containing the predetermined isotopic distribution. In a similar fashion, Hg with a predetermined isotopic distribution is obtained from different isotopic types of HgO. In this embodiment, the HgO is dissolved in an electrolytic solution of glacial acetic acid and H[sub 2]O. The isotopic specific Hg is then electrolytically plated onto a cathode and then recovered. 1 fig.

  10. Orchestrating Distributed Resource Ensembles for Petascale Science

    SciTech Connect (OSTI)

    Baldin, Ilya; Mandal, Anirban; Ruth, Paul; Yufeng, Xin

    2014-04-24

    Distributed, data-intensive computational science applications of interest to DOE scientific com- munities move large amounts of data for experiment data management, distributed analysis steps, remote visualization, and accessing scientific instruments. These applications need to orchestrate ensembles of resources from multiple resource pools and interconnect them with high-capacity multi- layered networks across multiple domains. It is highly desirable that mechanisms are designed that provide this type of resource provisioning capability to a broad class of applications. It is also important to have coherent monitoring capabilities for such complex distributed environments. In this project, we addressed these problems by designing an abstract API, enabled by novel semantic resource descriptions, for provisioning complex and heterogeneous resources from multiple providers using their native provisioning mechanisms and control planes: computational, storage, and multi-layered high-speed network domains. We used an extensible resource representation based on semantic web technologies to afford maximum flexibility to applications in specifying their needs. We evaluated the effectiveness of provisioning using representative data-intensive ap- plications. We also developed mechanisms for providing feedback about resource performance to the application, to enable closed-loop feedback control and dynamic adjustments to resource allo- cations (elasticity). This was enabled through development of a novel persistent query framework that consumes disparate sources of monitoring data, including perfSONAR, and provides scalable distribution of asynchronous notifications.