National Library of Energy BETA

Sample records for gdp growth rate

  1. New Contract Helps Portsmouth GDP Cleanup

    Broader source: Energy.gov [DOE]

    To accelerate the Portsmouth GDP cleanup efforts left over from the Cold War, the Department of Energy made a huge step forward in our nuclear environmental cleanup efforts.

  2. Growth Rates of Global Energy Systems and Future Outlooks

    SciTech Connect (OSTI)

    Hoeoek, Mikael; Li, Junchen; Johansson, Kersti; Snowden, Simon

    2012-03-15

    The world is interconnected and powered by a number of global energy systems using fossil, nuclear, or renewable energy. This study reviews historical time series of energy production and growth for various energy sources. It compiles a theoretical and empirical foundation for understanding the behaviour underlying global energy systems' growth. The most extreme growth rates are found in fossil fuels. The presence of scaling behaviour, i.e. proportionality between growth rate and size, is established. The findings are used to investigate the consistency of several long-range scenarios expecting rapid growth for future energy systems. The validity of such projections is questioned, based on past experience. Finally, it is found that even if new energy systems undergo a rapid 'oil boom'-development-i.e. they mimic the most extreme historical events-their contribution to global energy supply by 2050 will be marginal.

  3. The growth rate of gas hydrate from refrigerant R12

    SciTech Connect (OSTI)

    Kendoush, Abdullah Abbas; Jassim, Najim Abid; Joudi, Khalid A.

    2006-07-15

    Experimental and theoretical investigations were presented dealing with three phase direct-contact heat transfer by evaporation of refrigerant drops in an immiscible liquid. Refrigerant R12 was used as the dispersed phase, while water and brine were the immiscible continuous phase. A numerical solution is presented to predict the formation rate of gas hydrates in test column. The solution provided an acceptable agreement when compared with experimental results. The gas hydrate growth rate increased with time. It increased with increasing dispersed phase flow rate. The presence of surface-active sodium chloride in water had a strong inhibiting effect on the gas hydrate formation rate. (author)

  4. Accommodation of GDP-Linked Sugars in the Active Site of GDP-Perosamine Synthase

    SciTech Connect (OSTI)

    Cook, Paul D.; Carney, Amanda E.; Holden, Hazel M.

    2009-01-12

    Perosamine (4-amino-4,6-dideoxy-d-mannose), or its N-acetylated form, is one of several dideoxy sugars found in the O-antigens of such infamous Gram-negative bacteria as Vibrio cholerae O1 and Escherichia coli O157:H7. It is added to the bacterial O-antigen via a nucleotide-linked version, namely GDP-perosamine. Three enzymes are required for the biosynthesis of GDP-perosamine starting from mannose 1-phosphate. The focus of this investigation is GDP-perosamine synthase from Caulobacter crescentus, which catalyzes the final step in GDP-perosamine synthesis, the conversion of GDP-4-keto-6-deoxymannose to GDP-perosamine. The enzyme is PLP-dependent and belongs to the aspartate aminotransferase superfamily. It contains the typically conserved active site lysine residue, which forms a Schiff base with the PLP cofactor. Two crystal structures were determined for this investigation: a site-directed mutant protein (K186A) complexed with GDP-perosamine and the wild-type enzyme complexed with an unnatural ligand, GDP-3-deoxyperosamine. These structures, determined to 1.6 and 1.7 {angstrom} resolution, respectively, revealed the manner in which products, and presumably substrates, are accommodated within the active site pocket of GDP-perosamine synthase. Additional kinetic analyses using both the natural and unnatural substrates revealed that the K{sub m} for the unnatural substrate was unperturbed relative to that of the natural substrate, but the k{sub cat} was lowered by a factor of approximately 200. Taken together, these studies shed light on why GDP-perosamine synthase functions as an aminotransferase whereas another very similar PLP-dependent enzyme, GDP-4-keto-6-deoxy-d-mannose 3-dehydratase or ColD, catalyzes a dehydration reaction using the same substrate.

  5. Upscaling Calcite Growth Rates From the Mesoscale to the Macroscale

    SciTech Connect (OSTI)

    Bracco, Jacquelyn N [ORNL; Stack, Andrew G [ORNL; Steefel, Carl I [Lawrence Berkeley National Laboratory (LBNL)

    2013-01-01

    Quantitative prediction of mineral reaction rates in the subsurface remains a daunting task partly because a key parameter for macroscopic models, the reactive site density, is poorly constrained. Here we report atomic force microscopy (AFM) measurements on the calcite surface of monomolecular step densities, treated as equivalent to the reactive site density, as a function of aqueous calcium-to-carbonate ratio and saturation index. Data for the obtuse step orientation are combined with existing step velocity measurements to generate a model that predicts overall macroscopic calcite growth rates. The model is quantitatively consistent with several published macroscopic rates under a range of alkaline solution conditions, particularly for two of the most comprehensive data sets without the need for additional fit parameters. The model reproduces peak growth rates and its functional form is simple enough to be incorporated into reactive transport or other macroscopic models designed for predictions in porous media. However, it currently cannot model equilibrium, pH effects, and may overestimate rates at high aqueous calcium-to-carbonate ratios. The discrepancies in rates at high calcium-to-carbonate ratios may be due to differences in pre-treatment, such as exposing the seed material to SI 1.0 to generate/develop growth hillocks, or other factors.

  6. Nonlinear stochastic growth rates and redshift space distortions

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

    Jennings, Elise; Jennings, David

    2015-04-09

    The linear growth rate is commonly defined through a simple deterministic relation between the velocity divergence and the matter overdensity in the linear regime. We introduce a formalism that extends this to a nonlinear, stochastic relation between ? ? ?(x,t)/aH and ?. This provides a new phenomenological approach that examines the conditional mean (???), together with the fluctuations of ? around this mean. We measure these stochastic components using N-body simulations and find they are non-negative and increase with decreasing scale from ~10% at kmorerelation and nonlinearity are more pronounced for halos, M ? 5 x 10Mh?, compared to the dark matter at z 0 and 1. Nonlinear growth effects manifest themselves as a rotation of the mean (???) away from the linear theory prediction fLT?, where fLT is the linear growth rate. This rotation increases with wavenumber, k, and we show that it can be well-described by second order Lagrangian perturbation theory (2LPT) for k LT from two point statistics in redshift space. Given that the relationship between ? and ? is stochastic and nonlinear, this will have implications for the interpretation and precision of fLT extracted using models which assume a linear, deterministic expression.less

  7. Nonlinear stochastic growth rates and redshift space distortions

    SciTech Connect (OSTI)

    Jennings, Elise; Jennings, David

    2015-04-09

    The linear growth rate is commonly defined through a simple deterministic relation between the velocity divergence and the matter overdensity in the linear regime. We introduce a formalism that extends this to a nonlinear, stochastic relation between ? ? ?(x,t)/aH and ?. This provides a new phenomenological approach that examines the conditional mean (???), together with the fluctuations of ? around this mean. We measure these stochastic components using N-body simulations and find they are non-negative and increase with decreasing scale from ~10% at k<0.2hMpc? to 25% at k ~ 0.45hMpc? at z 0. Both the stochastic relation and nonlinearity are more pronounced for halos, M ? 5 x 10Mh?, compared to the dark matter at z 0 and 1. Nonlinear growth effects manifest themselves as a rotation of the mean (???) away from the linear theory prediction fLT?, where fLT is the linear growth rate. This rotation increases with wavenumber, k, and we show that it can be well-described by second order Lagrangian perturbation theory (2LPT) for k < 0.1 hMpc?. The stochasticity in the ? ? relation is not so simply described by 2LPT, and we discuss its impact on measurements of fLT from two point statistics in redshift space. Given that the relationship between ? and ? is stochastic and nonlinear, this will have implications for the interpretation and precision of fLT extracted using models which assume a linear, deterministic expression.

  8. Non-linear stochastic growth rates and redshift space distortions

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

    Jennings, Elise; Jennings, David

    2015-04-09

    The linear growth rate is commonly defined through a simple deterministic relation between the velocity divergence and the matter overdensity in the linear regime. We introduce a formalism that extends this to a non-linear, stochastic relation between θ = ∇ ∙ v(x,t)/aH and δ. This provides a new phenomenological approach that examines the conditional mean <θ|δ>, together with the fluctuations of θ around this mean. We also measure these stochastic components using N-body simulations and find they are non-negative and increase with decreasing scale from ~10 per cent at k < 0.2 h Mpc-1 to 25 per cent at kmore » ~ 0.45 h Mpc-1 at z = 0. Both the stochastic relation and non-linearity are more pronounced for haloes, M ≤ 5 × 1012 M⊙ h-1, compared to the dark matter at z = 0 and 1. Non-linear growth effects manifest themselves as a rotation of the mean <θ|δ> away from the linear theory prediction -fLTδ, where fLT is the linear growth rate. This rotation increases with wavenumber, k, and we show that it can be well-described by second-order Lagrangian perturbation theory (2LPT) fork < 0.1 h Mpc-1. Furthermore, the stochasticity in the θ – δ relation is not so simply described by 2LPT, and we discuss its impact on measurements of fLT from two-point statistics in redshift space. Furthermore, given that the relationship between δ and θ is stochastic and non-linear, this will have implications for the interpretation and precision of fLT extracted using models which assume a linear, deterministic expression.« less

  9. Dispersion relation and growth rate in a Cherenkov free electron laser: Finite axial magnetic field

    SciTech Connect (OSTI)

    Kheiri, Golshad; Esmaeilzadeh, Mahdi

    2013-12-15

    A theoretical analysis is presented for dispersion relation and growth rate in a Cherenkov free electron laser with finite axial magnetic field. It is shown that the growth rate and the resonance frequency of Cherenkov free electron laser increase with increasing axial magnetic field for low axial magnetic fields, while for high axial magnetic fields, they go to a saturation value. The growth rate and resonance frequency saturation values are exactly the same as those for infinite axial magnetic field approximation. The effects of electron beam self-fields on growth rate are investigated, and it is shown that the growth rate decreases in the presence of self-fields. It is found that there is an optimum value for electron beam density and Lorentz relativistic factor at which the maximum growth rate can take place. Also, the effects of velocity spread of electron beam are studied and it is found that the growth rate decreases due to the electron velocity spread.

  10. The effect of density gradient on the growth rate of relativistic Weibel instability

    SciTech Connect (OSTI)

    Mahdavi, M.; Khodadadi Azadboni, F.

    2014-02-15

    In this paper, the effect of density gradient on the Weibel instability growth rate is investigated. The density perturbations in the near corona fuel, where temperature anisotropy, η, is larger than the critical temperature anisotropy, η{sub c}, (η > η{sub c}), enhances the growth rate of Weibel instability due to the sidebands coupled with the electron oscillatory velocity. But for η < η{sub c}, the thermal spread of the energetic electrons reduces the growth rate. Also, the growth rate can be reduced if the relativistic parameter (Lorentz factor) is sufficiently large, γ > 2. The analysis shows that relativistic effects and density gradient tend to stabilize the Weibel instability. The growth rate can be reduced by 88% by reducing η by a factor of 100 and increasing relativistic parameter by a factor of 3.

  11. Ab initio determination of the instability growth rate of warm dense beryllium-deuterium interface

    SciTech Connect (OSTI)

    Wang, Cong; Zhang, Ping; Li, Zi; Li, DaFang

    2015-10-15

    Accurate knowledge about the interfacial unstable growth is of great importance in inertial confinement fusion. During implosions, the deuterium-tritium capsule is driven by laser beams or X-rays to access the strongly coupled and partially degenerated warm dense matter regime. At this stage, the effects of dissipative processes, such as diffusion and viscosity, have significant impact on the instability growth rates. Here, we present ab initio molecular dynamics simulations to determine the equations of state and the transport coefficients. Several models are used to estimate the reduction in the growth rate dispersion curves of Rayleigh-Taylor and Richtmyer-Meshkov instabilities with considering the presence of these dissipative effects. We show that these instability growth rates are effectively reduced when considering diffusion. The findings provide significant insights into the microscopic mechanism of the instability growth at the ablator-fuel interface and will refine the models used in the laser-driven hydrodynamic instability experiments.

  12. An Improved Reaction Rate Equation for Simulating the Ignition and Growth of Reaction in High Explosives

    SciTech Connect (OSTI)

    Murphy, M J

    2010-03-08

    We describe an improved reaction rate equation for simulating ignition and growth of reaction in high explosives. It has been implemented into CALE and ALE3D as an alternate to the baseline the Lee-Tarver reactive flow model. The reactive flow model treats the explosive in two phases (unreacted/reactants and reacted/products) with a reaction rate equation to determine the fraction reacted, F. The improved rate equation has fewer parameters, is continuous with continuous derivative, results in a unique set of reaction rate parameters for each explosive while providing the same functionality as the baseline rate equation. The improved rate equation uses a cosine function in the ignition term and a sine function in the growth and completion terms. The improved rate equation is simpler with fewer parameters.

  13. Primary water stress corrosion crack growth rates in Alloy 600 steam generator tubing

    SciTech Connect (OSTI)

    Lott, R.G.; Jacko, R.J.; Gold, R.E.

    1992-12-31

    Direct measurements of SCC crack growth rates have been used to determine the effects of changes in PWR primary water chemistry on the stress corrosion cracking behavior of Alloy 600 steam generator tubing. Reversing current DC potential measurement techniques have been adapted for use on thin walled tubing containing through-wall circumferential cracks. These techniques have been used to monitor crack rates in Alloy 600 tubing exposed to typical PWR primary water chemistries at 330{degrees}C. Crack growth rate studies, conducted under well defined stress intensity conditions, provide a sensitivity in the assessment of stress corrosion cracking susceptibility that is not possible using more traditional techniques. Preliminary studies have been conducted to determine the effects of B and Li concentrations on the stress corrosion crack growth rate of Alloy 600 tubing.

  14. Characterization of a Ras Mutant with Identical GDP- and GTP-Bound Structures

    SciTech Connect (OSTI)

    Ford, B.; Boykevisch, S; Zhao, C; Kunzelmann, S; Bar-Sagi, D; Herrmann, C; Nassar, N

    2009-01-01

    We previously characterized the G60A mutant of Ras and showed that the switch regions of the GTP-bound but not the GDP-bound form of this mutant adopt an 'open conformation' similar to that seen in nucleotide-free Ras. Here, we mutate Lys147 of the conserved {sup 145}SAK{sup 147} motif in the G60A background and characterize the resulting double mutant (DM). We show that RasDM is the first structure of a Ras protein with identical GDP- and GTP-bound structures. Both structures adopt the open conformation of the active form of RasG60A. The increase in the accessible surface area of the nucleotide is consistent with a 4-fold increase in its dissociation rate. Stopped-flow experiments show no major difference in the two-step kinetics of association of GDP or GTP with the wild type, G60A, or RasDM. Addition of Sos fails to accelerate nucleotide exchange. Overexpression of the G60A or double mutant of Ras in COS-1 cells fails to activate Erk and shows a strong dominant negative effect. Our data suggest that flexibility at position 60 is required for proper Sos-catalyzed nucleotide exchange and that structural information is somehow shared among the switch regions and the different nucleotide binding motifs.

  15. Structures of NodZ ?1,6-fucosyltransferase in complex with GDP and GDP-fucose

    SciTech Connect (OSTI)

    Brzezinski, Krzysztof; Dauter, Zbigniew; Jaskolski, Mariusz

    2012-02-01

    Crystal structures of the bacterial ?1,6-fucosyltransferase NodZ in complex with GDP and GDP-fucose are presented. Rhizobial NodZ ?1,6-fucosyltransferase (?1,6-FucT) catalyzes the transfer of the fucose (Fuc) moiety from guanosine 5?-diphosphate-?-l-fucose to the reducing end of the chitin oligosaccharide core during Nod-factor (NF) biosynthesis. NF is a key signalling molecule required for successful symbiosis with a legume host for atmospheric nitrogen fixation. To date, only two ?1,6-FucT structures have been determined, both without any donor or acceptor molecule that could highlight the structural background of the catalytic mechanism. Here, the first crystal structures of ?1,6-FucT in complex with its substrate GDP-Fuc and with GDP, which is a byproduct of the enzymatic reaction, are presented. The crystal of the complex with GDP-Fuc was obtained through soaking of native NodZ crystals with the ligand and its structure has been determined at 2.35 resolution. The fucose residue is exposed to solvent and is disordered. The enzymeproduct complex crystal was obtained by cocrystallization with GDP and an acceptor molecule, penta-N-acetyl-l-glucosamine (penta-NAG). The structure has been determined at 1.98 resolution, showing that only the GDP molecule is present in the complex. In both structures the ligands are located in a cleft formed between the two domains of NodZ and extend towards the C-terminal domain, but their conformations differ significantly. The structures revealed that residues in three regions of the C-terminal domain, which are conserved among ?1,2-, ?1,6- and protein O-fucosyltransferases, are involved in interactions with the sugar-donor molecule. There is also an interaction with the side chain of Tyr45 in the N-terminal domain, which is very unusual for a GT-B-type glycosyltransferase. Only minor conformational changes of the protein backbone are observed upon ligand binding. The only exception is a movement of the loop located between

  16. Collaborative Project: Understanding the Chemical Processes tat Affect Growth rates of Freshly Nucleated Particles

    SciTech Connect (OSTI)

    McMurry, Peter; Smuth, James

    2015-11-12

    This final technical report describes our research activities that have, as the ultimate goal, the development of a model that explains growth rates of freshly nucleated particles. The research activities, which combine field observations with laboratory experiments, explore the relationship between concentrations of gas-phase species that contribute to growth and the rates at which those species are taken up. We also describe measurements of the chemical composition of freshly nucleated particles in a variety of locales, as well as properties (especially hygroscopicity) that influence their effects on climate.

  17. Radiocarbon-Based Ages and Growth Rates of Bamboo Corals from the Gulf of Alaska

    SciTech Connect (OSTI)

    Roark, E B; Guilderson, T P; Flood-Page, S; Dunbar, R B; Ingram, B L; Fallon, S J; McCulloch, M

    2004-12-12

    Deep-sea coral communities have long been recognized by fisherman as areas that support large populations of commercial fish. As a consequence, many deep-sea coral communities are threatened by bottom trawling. Successful management and conservation of this widespread deep-sea habitat requires knowledge of the age and growth rates of deep-sea corals. These organisms also contain important archives of intermediate and deep-water variability, and are thus of interest in the context of decadal to century-scale climate dynamics. Here, we present {Delta}{sup 14}C data that suggest that bamboo corals from the Gulf of Alaska are long-lived (75-126 years) and that they acquire skeletal carbon from two distinct sources. Independent verification of our growth rate estimates and coral ages is obtained by counting seasonal Sr/Ca cycles and probable lunar cycle growth bands.

  18. Oil-Consumption-Weighted GDP: Description, Calculation, and Comparison

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

    Oil-Consumption-Weighted GDP: Description, Calculation, and Comparison Vipin Arora, Tyler Hodge, and Tancred Lidderdale May 2016 Independent Statistics & Analysis www.eia.gov U.S. Energy Information Administration Washington, DC 20585 This paper is released to encourage discussion and critical comment. The analysis and conclusions expressed here are those of the authors and not necessarily those of the U.S. Energy Information Administration. Our thanks to Vinay Tripathi, summer intern from

  19. Structures of NodZ [alpha]1,6-fucosyltransferase in complex with GDP and GDP-fucose

    SciTech Connect (OSTI)

    Brzezinski, Krzysztof; Dauter, Zbigniew; Jaskolski, Mariusz

    2012-03-26

    Rhizobial NodZ {alpha}1,6-fucosyltransferase ({alpha}1,6-FucT) catalyzes the transfer of the fucose (Fuc) moiety from guanosine 5'-diphosphate-{beta}-L-fucose to the reducing end of the chitin oligosaccharide core during Nod-factor (NF) biosynthesis. NF is a key signaling molecule required for successful symbiosis with a legume host for atmospheric nitrogen fixation. To date, only two {alpha}1,6-FucT structures have been determined, both without any donor or acceptor molecule that could highlight the structural background of the catalytic mechanism. Here, the first crystal structures of {alpha}1,6-FucT in complex with its substrate GDP-Fuc and with GDP, which is a byproduct of the enzymatic reaction, are presented. The crystal of the complex with GDP-Fuc was obtained through soaking of native NodZ crystals with the ligand and its structure has been determined at 2.35 {angstrom} resolution. The fucose residue is exposed to solvent and is disordered. The enzyme-product complex crystal was obtained by cocrystallization with GDP and an acceptor molecule, penta-N-acetyl-L-glucosamine (penta-NAG). The structure has been determined at 1.98 {angstrom} resolution, showing that only the GDP molecule is present in the complex. In both structures the ligands are located in a cleft formed between the two domains of NodZ and extend towards the C-terminal domain, but their conformations differ significantly. The structures revealed that residues in three regions of the C-terminal domain, which are conserved among {alpha}1,2-, {alpha}1,6- and protein O-fucosyltransferases, are involved in interactions with the sugar-donor molecule. There is also an interaction with the side chain of Tyr45 in the N-terminal domain, which is very unusual for a GT-B-type glycosyltransferase. Only minor conformational changes of the protein backbone are observed upon ligand binding. The only exception is a movement of the loop located between strand {beta}C2 and helix {alpha}C3. In addition, there is

  20. Effect of different carrier gases and their flow rates on the growth of carbon nanotubes

    SciTech Connect (OSTI)

    Tewari, Aarti; Sharma, Suresh C.

    2015-04-15

    The present paper examines the effect of different carrier gases and their flow rates on the growth of carbon nanotubes (CNTs). A theoretical model is developed incorporating the charging rate of the carbon nanotube, kinetics of all the plasma species, and the growth rate of the CNTs because of diffusion and accretion of ions on the catalyst nanoparticle. The three different carrier gases, i.e., argon (Ar), ammonia, and nitrogen, are considered in the present investigation, and flow rates of all the three carrier gases are varied individually (keeping the flow rates of hydrocarbon and hydrogen gas constant) to investigate the variations in the number densities of hydrocarbon and hydrogen ions in the plasma and their consequent effects on the height and radius of CNT. Based on the results obtained, it is concluded that Ar favors the formation of CNTs with larger height and radius whereas ammonia contributes to better height of CNT but decreases the radius of CNT, and nitrogen impedes both the height and radius of CNT. The present work can serve to the better understanding of process parameters during growth of CNTs by a plasma enhanced chemical vapor deposition process.

  1. Effect of cold work on the growth rates of stress corrosion cracks in structural materials of nuclear systems

    SciTech Connect (OSTI)

    Magdowski, R.; Speidel, M.O.

    1996-10-01

    The growth rates of stress corrosion cracks in austenitic stainless steels and nickel base alloy 600 exposed to simulated boiling water reactor coolant were measured by fracture mechanics testing techniques. Cold work may increase the crack growth rates up to one hundred times. In both, the annealed condition and the cold worked condition, the stress corrosion crack growth rates are independent of stress intensity over a wide K-range and crack growth rates correlate well with yield strength and hardness. In the annealed condition the fracture path is intergranular, but higher degrees of cold work introduce higher proportions of transgranular stress corrosion cracking.

  2. Magnesite Step Growth Rates as a Function of the Aqueous Magnesium:Carbonate Ratio

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

    Bracco, Jacquelyn N.; Stack, Andrew G.; Higgins, Steven R.

    2014-10-01

    Step velocities of monolayer-height steps on the (101⁻4) magnesite surface have been measured as functions of the aqueous magnesium-to-carbonate ratio and saturation index (SI) using a hydrothermal atomic force microscope (HAFM). At SI ≤ 1.9 and 80-90 °C, step velocities were found to be invariant with changes in the magnesium-to-carbonate ratio, an observation in contrast with standard models for growth and dissolution of ionically-bonded, multi-component crystals. However, at high saturation indices (SI = 2.15), step velocities displayed a ratio dependence, maximized at magnesium-to-carbonate ratios slightly greater than 1:1. Traditional affinity-based models were unable to describe growth rates at the highermore » saturation index. Step velocities also could not be modeled solely through nucleation of kink sites, in contrast to other minerals whose bonding between constituent ions is also dominantly ionic in nature, such as calcite and barite. Instead, they could be described only by a model that incorporates both kink nucleation and propagation. Based on observed step morphological changes at these higher saturation indices, the step velocity maximum at SI = 2.15 is likely due to the rate of attachment to propagating kink sites overcoming the rate of detachment from kink sites as the latter becomes less significant under far from equilibrium conditions.« less

  3. Influence of finite radial geometry on the growth rate of ion-channel free electron laser

    SciTech Connect (OSTI)

    Bahmani, Mohammad; Hamzehpour, Hossein; Hasanbeigi, Ali

    2013-11-15

    The influence of finite radial geometry on the instability of a tenuous relativistic electron beam propagating in an ion-channel in a waveguide is investigated. The instability analysis is based on the linearized Vlasov-Maxwell equations for the perturbation about a self-consistent beam equilibrium. With the help of characteristic method the dispersion relation for the TE-mode is derived and analyzed through the numerical solutions. It is found that the positioning of the beam radius R{sub b} relative to the waveguide radius R{sub c}, and the ion-channel frequency can have a large influence on the maximum growth rate and corresponding wave number.

  4. Roughness Optimization at High Modes for GDP CHx Microshells

    SciTech Connect (OSTI)

    Theobald, M.; Dumay, B.; Chicanne, C.; Barnouin, J.; Legaie, O.; Baclet, P.

    2004-03-15

    For the ''Megajoule'' Laser (LMJ) facility of the CEA, amorphous hydrogenated carbon (a-C:H) is the nominal ablator to be used for inertial confinement fusion (ICF) experiments. These capsules contain the fusible deuterium-tritium mixture to achieve ignition. Coatings are prepared by glow discharge polymerization (GDP) with trans-2-butene and hydrogen. The films properties have been investigated. Laser fusion targets must have optimized characteristics: a diameter of about 2.4 mm for LMJ targets, a thickness up to 175 {mu}m, a sphericity and a thickness concentricity better than 99% and an outer and an inner roughness lower than 20 nm at high modes. The surface finish of these laser fusion targets must be extremely smooth to minimize hydrodynamic instabilities.Movchan and Demchishin, and later Thornton introduced a structure zone model (SZM) based on both evaporated and sputtered metals. They investigated the influence of base temperature and the sputtering gas pressure on structure and properties of thick polycrystalline coatings of nickel, titanium, tungsten, aluminum oxide. An original cross-sectional analysis by atomic force microscopy (AFM) allows amorphous materials characterization and permits to make an analogy between the amorphous GDP material and the existing model (SZM). The purpose of this work is to understand the relationship between the deposition parameters, the growing structures and the surface roughness.The coating structure as a function of deposition parameters was first studied on plane silicon substrates and then optimized on PAMS shells. By adjusting the coating parameters, the structures are modified, and in some case, the high modes roughness decreases dramatically.

  5. Polymer Growth Rate in a Wire Chamber with Oxygen,Water, or Alcohol Gas Additives

    SciTech Connect (OSTI)

    Boyarski, Adam; /SLAC

    2008-07-02

    The rate of polymer growth on wires was measured in a wire chamber while the chamber was aged initially with helium-isobutane (80:20) gas, and then with either oxygen, water, or alcohol added to the gas. At the completion of the aging process for each gas mixture, the carbon content on the wires was measured in a SEM/EDX instrument. The same physical wires were used in all the gas mixtures, allowing measurement of polymer build up or polymer depletion by each gas additive. It is found that the rate of polymer growth is not changed by the presence of oxygen, water or alcohol. Conjecture that oxygen reduces breakdown by removing polymer deposits on field wires is negated by these measurements. Instead, it appears that the reduced breakdown is due to lower resistance in the polymer from oxygen ions being transported into the polymer. It is also observed that field wires bombarded by the electrons in the SEM and then placed back into the chamber show an abundance of single electrons being emitted, indicating that electron charge is stored in the polymer layer and that a high electric field is necessary to remove the charge.

  6. Cloning and characterization of GDP-perosamine synthetase (Per) from Escherichia coli O157:H7 and synthesis of GDP-perosamine in vitro

    SciTech Connect (OSTI)

    Zhao Guohui; Liu Jun; Liu Xiang; Chen Min; Zhang Houcheng Wang, Peng George

    2007-11-23

    GDP-perosamine synthetase (Per, E.C. not yet classified) is important to the synthesis of Escherichia coli O157:H7 O-antigen. The mutant in per gene can disrupt the synthesis of O157 O-antigen. In this study, GDP-perosamine synthetase was cloned from E. coli O157:H7 and over-expressed in E. coli BL21 (DE3). The recombinant His-tagged Per fusion protein was a decamer with molecular weight of 431 kDa. The optimal pH value of this recombinant protein was 7.5. The divalent ions had no significant effect on Per-catalyzed reaction. The K{sub m} and K{sub cat}/K{sub m} for GDP-4-keto-6-deoxy-D-mannose were 0.09 mM and 2.1 x 10{sup 5} M{sup -1} S{sup -1}, and those for L-glutamate were 2 mM and 0.52 x 10{sup 5} M{sup -1}S{sup -1}, respectively. Per was used to synthesize GDP-perosamine from GDP-mannose together with recombinant GDP-mannose dehydratase (GMD, E.C. 4.2.1.47). The purified GDP-perosamine was identified by MS and NMR. In summary, this work provided a feasible approach for the synthesis of GDP-perosamine which can lead to the study of LPS biosynthesis of pathogenic E. coli O157:H7.

  7. Effects of ion abundances on electromagnetic ion cyclotron wave growth rate in the vicinity of the plasmapause

    SciTech Connect (OSTI)

    Henning, F. D. Mace, R. L.

    2014-04-15

    Electromagnetic ion cyclotron (EMIC) waves in multi-ion species plasmas propagate in branches. Except for the branch corresponding to the heaviest ion species, which has only a resonance at its gyrofrequency, these branches are bounded below by a cutoff frequency and above by a resonant gyrofrequency. The condition for wave growth is determined by the thermal anisotropies of each ion species, j, which sets an upper bound, ?{sub j}{sup ?}, on the wave frequency below which that ion species contributes positively to the growth rate. It follows that the relative positions of the cutoffs and the critical frequencies ?{sub j}{sup ?} play a crucial role in determining whether a particular wave branch will be unstable. The effect of the magnetospheric ion abundances on the growth rate of each branch of the EMIC instability in a model where all the ion species have kappa velocity distributions is investigated by appealing to the above ideas. Using the variation of the cutoff frequencies predicted by cold plasma theory as a guide, optimal ion abundances that maximise the EMIC instability growth rate are sought. When the ring current is comprised predominantly of H{sup +} ions, all branches of the EMIC wave are destabilised, with the proton branch having the maximum growth rate. When the O{sup +} ion abundance in the ring current is increased, a decrease in the growth rate of the proton branch and cyclotron damping of the helium branch are observed. The oxygen branch, on the other hand, experiences an increase in the maximum growth rate with an increase in the O{sup +} ion abundance. When the ring current is comprised predominantly of He{sup +} ions, only the helium and oxygen branches of the EMIC wave are destabilised, with the helium branch having the maximum growth rate.

  8. Effect of mono- and dichromatic light quality on growth rates and photosynthetic performance of Synechococcus sp. PCC 7002

    SciTech Connect (OSTI)

    Bernstein, Hans C.; Konopka, Allan; Melnicki, Matthew R.; Hill, Eric A.; Kucek, Leo A.; Zhang, Shuyi; Shen, Gaozhong; Bryant, Donald A.; Beliaev, Alex S.

    2014-09-19

    Synechococcus sp. PCC 7002 was grown to steady state in optically thin turbidostat cultures under conditions for which light quantity and quality was systematically varied by modulating the output of narrow-band LEDs. Cells were provided photons absorbed primarily by chlorophyll (680 nm) or phycocyanin (630 nm) as the organism was subjected to four distinct mono- and dichromatic regimes. During cultivation with dichromatic light, growth rates displayed by Synechococcus sp. PCC 7002 were generally proportional to the total incident irradiance at values < 275 mol photons m-2 s-1 and were not affected by the ratio of 630:680 nm wavelengths. Notably, under monochromatic light conditions, cultures exhibited similar growth rates only when they were irradiated with 630 nm light; cultures irradiated with only 680 nm light grew at rates that were 60 70% of those under other light quality regimes at equivalent irradiances. The functionality of photosystem II and associated processes such as maximum rate of photosynthetic electron transport, rate of cyclic electron flow, and rate of dark respiration generally increased as a function of growth rate. Nonetheless, some of the photophysiological parameters measured here displayed distinct patterns with respect to growth rate of cultures adapted to a single wavelength including phycobiliprotein content, which increased under severely light-limited growth conditions. Additionally, the ratio of photosystem II to photosystem I increased approximately 40% over the range of growth rates, although cells grown with 680 nm light only had the highest ratios. These results suggest the presence of effective mechanisms which allow acclimation of Synechococcus sp. PCC 7002 acclimation to different irradiance conditions.

  9. Mechanical Properties of Thin GDP Shells Used as Cryogenic Direct Drive Targets at OMEGA

    SciTech Connect (OSTI)

    Nikroo, A.; Czechowicz, D.G.; Chen, K.C.; Dicken, M.; Morris, C.; Andrews, R.; Greenwood, A.; Castillo, E.

    2004-03-15

    Thin glow discharge polymer (GDP) shells are currently used as the targets for cryogenic direct drive laser fusion experiments. These shells need to be filled with nearly 1000 atm of D{sub 2} and cooled to cryogenic temperatures without failing due to buckling and bursting pressures they experience in this process. Therefore, the mechanical and permeation properties of these shells are of utmost importance in successful and rapid filling with D{sub 2}. In this paper, we present an overview of buckle and burst pressures of several different types of GDP shells. These include those made using traditional GDP deposition parameters ('standard GDP') using a high deposition pressure and using modified parameters ('strong GDP') of low deposition pressure that leads to more robust shells.

  10. MECHANICAL PROPERTIES OF THIN GDP SHELLS USED AS CRYOGENIC DIRECT DRIVE TARGETS AT OMEGA

    SciTech Connect (OSTI)

    NIKROO,A; CZECHOWICZ,D; CHEN,K.C; DICKEN,M; MORRIS,C; ANDREWS,R; GREENWOOD,A.L; CASTILLO,E

    2003-06-01

    OAK-B135 Thin glow discharge polymer (GDP) shells are currently used as the targets for cryogenic direct drive laser fusion experiments. These shells need to be filled with nearly 1000 atm of D{sub 2} and cooled to cryogenic temperatures without failing due to buckling and bursting pressures they experience in this process. Therefore, the mechanical and permeation properties of these shells are of utmost importance in successful and rapid filling with D{sub 2}. In this paper, they present an overview of buckle and burst pressures of several different types of GDP shells. These include those made using traditional GDP deposition parameters (standard GDP) using a high deposition pressure and using modified parameters (strong GDP) of low deposition pressure that leads to more robust shells.

  11. Biochemical characterization of GDP-L-fucose de novo synthesis pathway in fungus Mortierella alpina

    SciTech Connect (OSTI)

    Ren, Yan; Perepelov, Andrei V.; Wang, Haiyan; Zhang, Hao; Knirel, Yuriy A.; Wang, Lei; Chen, Wei

    2010-01-22

    Mortierella alpina is a filamentous fungus commonly found in soil, which is able to produce large amount of polyunsaturated fatty acids. L-Fucose is an important sugar found in a diverse range of organisms, playing a variety of biological roles. In this study, we characterized the de novo biosynthetic pathway of GDP-L-fucose (the nucleotide-activated form of L-fucose) in M. alpina. Genes encoding GDP-D-mannose 4,6-dehydratase (GMD) and GDP-keto-6-deoxymannose 3,5-epimerase/4-reductase (GMER) were expressed heterologously in Escherichia coli. The recombinant enzymes were produced as His-tagged fusion proteins. Conversion of GDP-mannose to GDP-4-keto-6-deoxy mannose by GMD and GDP-4-keto-6-deoxy mannose to GDP-L-fucose by GMER were analyzed by capillary electrophoresis, electro-spray ionization-mass spectrometry, and nuclear magnetic resonance spectroscopy. The k{sub m} values of GMD for GDP-mannose and GMER for GDP-4-keto-6-deoxy mannose were determined to be 0.77 mM and 1.047 mM, respectively. Both NADH and NADPH may be used by GMER as the coenzyme. The optimum temperature and pH were determined to be 37 {sup o}C and pH 9.0 (GMD) or pH 7.0 (GMER). Divalent cations are not required for GMD and GMER activity, and the activities of both enzymes may be enhanced by DTT. To our knowledge this is the first report on the characterization of GDP-L-fucose biosynthetic pathway in fungi.

  12. Daily treatment with {alpha}-naphthoflavone enhances follicular growth and ovulation rate in the rat

    SciTech Connect (OSTI)

    Barreiro, Karina A.; Di Yorio, Maria P.; Artillo-Guida, Romina D.; Paz, Dante A.; Faletti, Alicia G.

    2011-04-01

    The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor and the first protein involved in a variety of physiological and toxicological processes, including those of xenobiotic metabolizing enzymes. AhR has been found in the ovary of many species and seems to mediate the ovarian toxicity of many environmental contaminants, which are AhR ligands. However, the role of AhR in the ovarian function is unknown. Therefore, the aim of this work was to study the action of {alpha}-naphthoflavone ({alpha}NF), known to be an AhR antagonist, on both follicular growth and ovulation. Immature Sprague-Dawley rats were daily injected intraperitoneally with {alpha}NF (0.1-80 mg/kg) or vehicle for 12 days, and primed with gonadotrophins (eCG/hCG) to induce follicular growth and ovulation. Ovaries were obtained 20 h after hCG administration. By means of immunohistochemistry, we found that the numbers of primordial, primary and antral follicles were increased in rats treated with 80 mg/kg {alpha}NF and that there were no differences with other doses. Likewise, the ovarian weight and the ovulation rate, measured by both number of oocytes within oviducts and corpora lutea in ovarian sections, were increased when the rats received either 1 or 10 mg/kg daily. Although further studies are necessary to know the mechanism of action of {alpha}NF, it is possible that the different ovarian processes can be differentially responsive to the presence of different levels of {alpha}NF, and that the same or different endogenous AhR ligands can be involved in these ovarian processes in a cell type-dependent manner.

  13. X-ray, NMR, and Mutational Studies of the Catalytic Cycle of the GDP-Mannose Mannosyl Hydrolase Reaction

    SciTech Connect (OSTI)

    Gabelli,S.; Azurmendi, H.; Bianchet, M.; Amzel, L.; Mildva, A.

    2006-01-01

    GDP-mannose hydrolase catalyzes the hydrolysis with inversion of GDP-{alpha}-D-hexose to GDP and {beta}-D-hexose by nucleophilic substitution by water at C1 of the sugar. Two new crystal structures (free enzyme and enzyme-substrate complex), NMR, and site-directed mutagenesis data, combined with the structure of the enzyme-product complex reported earlier, suggest a four-stage catalytic cycle. An important loop (L6, residues 119-125) contains a ligand to the essential Mg{sup 2+} (Gln-123), the catalytic base (His-124), and three anionic residues. This loop is not ordered in the X-ray structure of the free enzyme due to dynamic disorder, as indicated by the two-dimensional 1H-15N HMQC spectrum, which shows selective exchange broadening of the imidazole nitrogen resonances of His-124 (k{sub ex} = 6.6 x 10{sup 4} s{sup -1}). The structure of the enzyme-Mg{sup 2+}-GDP-mannose substrate complex of the less active Y103F mutant shows loop L6 in an open conformation, while the structure of the enzyme-Mg{sup 2+}-GDP product complex showed loop L6 in a closed, 'active' conformation. 1H-15N HMQC spectra show the imidazole N of His-124 to be unprotonated, appropriate for general base catalysis. Substituting Mg{sup 2+} with the more electrophilic metal ions Mn{sup 2+} or Co{sup 2+} decreases the pK{sub a} in the pH versus k{sub cat} rate profiles, showing that deprotonation of a metal-bound water is partially rate-limiting. The H124Q mutation, which decreases k{sub cat} 103.4-fold and largely abolishes its pH dependence, is rescued by the Y103F mutation, which increases k{sub cat} 23-fold and restores its pH dependence. The structural basis of the rescue is the fact that the Y103F mutation shifts the conformational equilibrium to the open form moving loop L6 out of the active site, thus permitting direct access of the specific base hydroxide from the solvent. In the proposed dissociative transition state, which occurs in the closed, active conformation of the enzyme, the

  14. The Stress Corrosion Crack Growth Rate of Alloy 600 Heat Affected Zones Exposed to High Purity Water

    SciTech Connect (OSTI)

    George A. Young; Nathan Lewis

    2003-04-05

    Grain boundary chromium carbides improve the resistance of nickel based alloys to primary water stress corrosion cracking (PWSCC). However, in weld heat affected zones (HAZ's), thermal cycles from fusion welding can solutionize beneficial grain boundary carbides, produce locally high residual stresses and strains, and promote PWSCC. The present research investigates the crack growth rate of an A600 HAZ as a function of test temperature. The A600 HAZ was fabricated by building up a gas-tungsten-arc-weld deposit of EN82H filler metal onto a mill-annealed A600 plate. Fracture mechanics based, stress corrosion crack growth rate testing was performed in high purity water between 600 F and 680 F at an initial stress intensity factor of 40 ksi {radical}in and at a constant electrochemical potential. The HAZ samples exhibited significant SCC, entirely within the HAZ at all temperatures tested. While the HAZ samples showed the same temperature dependence for SCC as the base material (HAZ: 29.8 {+-} 11.2{sub 95%} kcal/mol vs A600 Base: 35.3 {+-} 2.58{sub 95%} kcal/mol), the crack growth rates were {approx} 30X faster than the A600 base material tested at the same conditions. The increased crack growth rates of the HAZ is attributed to fewer intergranular chromium rich carbides and to increased plastic strain in the HAZ as compared to the unaffected base material.

  15. Crystal structure of a tetrameric GDP-D-mannose 4,6-dehydratase from a bacterial GDP-D-rhamnose biosynthetic pathway

    SciTech Connect (OSTI)

    Webb, N.A.; Mulichak, A.M.; Lam, J.S.; Rocchetta, H.L.; Garavito, R.M.

    2010-03-08

    D-Rhamnose is a rare 6-deoxy monosaccharide primarily found in the lipopolysaccharide of pathogenic bacteria, where it is involved in host-bacterium interactions and the establishment of infection. The biosynthesis of D-rhamnose proceeds through the conversion of GDP-D-mannose by GDP-D-mannose 4,6-dehydratase (GMD) to GDP-4-keto-6-deoxymannose, which is subsequently reduced to GDP-D-rhamnose by a reductase. We have determined the crystal structure of GMD from Pseudomonas aeruginosa in complex with NADPH and GDP. GMD belongs to the NDP-sugar modifying subfamily of the short-chain dehydrogenase/reductase (SDR) enzymes, all of which exhibit bidomain structures and a conserved catalytic triad (Tyr-XXX-Lys and Ser/Thr). Although most members of this enzyme subfamily display homodimeric structures, this bacterial GMD forms a tetramer in the same fashion as the plant MUR1 from Arabidopsis thaliana. The cofactor binding sites are adjoined across the tetramer interface, which brings the adenosyl phosphate moieties of the adjacent NADPH molecules to within 7 {angstrom} of each other. A short peptide segment (Arg35-Arg43) stretches into the neighboring monomer, making not only protein-protein interactions but also hydrogen bonding interactions with the neighboring cofactor. The interface hydrogen bonds made by the Arg35-Arg43 segment are generally conserved in GMD and MUR1, and the interacting residues are highly conserved among the sequences of bacterial and eukaryotic GMDs. Outside of the Arg35-Arg43 segment, residues involved in tetrameric contacts are also quite conserved across different species. These observations suggest that a tetramer is the preferred, and perhaps functionally relevant, oligomeric state for most bacterial and eukaryotic GMDs.

  16. Metal-to-Insulator Transition in Anatase TiO2 Thin Films Induced by Growth Rate Modulation

    SciTech Connect (OSTI)

    Tachikawa, T; Minohara, M.; Nakanishi, Y.; Hikita, Y.; Yoshita, M.; Akiyama, H.; Bell, C.; Hwang, H.Y.

    2012-06-21

    We demonstrate control of the carrier density of single phase anatase TiO{sub 2} thin films by nearly two orders of magnitude by modulating the growth kinetics during pulsed laser deposition, under fixed thermodynamic conditions. The resistivity and the intensity of the photoluminescence spectra of these TiO{sub 2} samples, both of which correlate with the number of oxygen vacancies, are shown to depend strongly on the growth rate. A quantitative model is used to explain the carrier density changes.

  17. Rate Of Oxidation Of Plasma Polymer (GDP or CH) (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Subject: 36 MATERIALS SCIENCE; 42 ENGINEERING; ATOMS; COATINGS; DESIGN; OXIDATION; PLASMA; PLASTICS; POLYMERS; REMOVAL; SPECIFICATIONS Word Cloud More Like This Full Text preview ...

  18. Rate Of Oxidation Of Plasma Polymer (GDP or CH) (Technical Report...

    Office of Scientific and Technical Information (OSTI)

    Based on this result we believe the NIF capsule specification for O can safely be lowered to 0.2 atom %, and this level should be used in future design calculations. Authors: Cook, ...

  19. Study of radial growth rate and size control of silicon nanocrystals in square-wave-modulated silane plasmas

    SciTech Connect (OSTI)

    Nguyen-Tran, Th.; Roca i Cabarrocas, P.; Patriarche, G.

    2007-09-10

    The growth of silicon nanocrystals in high pressure and high dilution silane plasmas is investigated by using the temporal evolution of the self-bias on the radio frequency electrode and transmission electron microscopy. A square-wave-modulated plasma was used in order to control the growth of monodispersed nanoparticles with sizes smaller than 12 nm. To this end, the plasma on time was kept below 1 s. The radial growth rate of nanoparticles was varied in the range from 7.5 to 75 nm/s by changing silane partial pressure. Nanoparticles grown in silane-helium discharges have been found amorphous while they are crystalline in silane-hydrogen-argon discharges. Surprisingly, the crystallization in the gaseous phase does not depend on how slow or fast the particles grow but on the presence of atomic hydrogen.

  20. Determination of redox reaction rates and orders by in situ liquid cell electron microscopy of Pd and Au solution growth

    SciTech Connect (OSTI)

    Sutter, Eli A.; Sutter, Peter W.

    2014-11-19

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pd deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. In addition, by comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.

  1. Determination of redox reaction rates and orders by in situ liquid cell electron microscopy of Pd and Au solution growth

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

    Sutter, Eli A.; Sutter, Peter W.

    2014-11-19

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e⁻aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e⁻aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pdmore » deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e⁻aq]. In addition, by comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e⁻aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.« less

  2. Prediction of pure water stress corrosion cracking (PWSCC) in nickel base alloys using crack growth rate models

    SciTech Connect (OSTI)

    Thompson, C.D.; Krasodomski, H.T.; Lewis, N.; Makar, G.L.

    1995-02-22

    The Ford/Andresen slip dissolution SCC model, originally developed for stainless steel components in BWR environments, has been applied to Alloy 600 and Alloy X-750 tested in deaerated pure water chemistry. A method is described whereby the crack growth rates measured in compact tension specimens can be used to estimate crack growth in a component. Good agreement was found between model prediction and measured SCC in X-750 threaded fasteners over a wide range of temperatures, stresses, and material condition. Most data support the basic assumption of this model that cracks initiate early in life. The evidence supporting a particular SCC mechanism is mixed. Electrochemical repassivation data and estimates of oxide fracture strain indicate that the slip dissolution model can account for the observed crack growth rates, provided primary rather than secondary creep rates are used. However, approximately 100 cross-sectional TEM foils of SCC cracks including crack tips reveal no evidence of enhanced plasticity or unique dislocation patterns at the crack tip or along the crack to support a classic slip dissolution mechanism. No voids, hydrides, or microcracks are found in the vicinity of the crack tips creating doubt about classic hydrogen related mechanisms. The bulk oxide films exhibit a surface oxide which is often different than the oxides found within a crack. Although bulk chromium concentration affects the rate of SCC, analytical data indicates the mechanism does not result from chromium depletion at the grain boundaries. The overall findings support a corrosion/dissolution mechanism but not one necessarily related to slip at the crack tip.

  3. Growth rates of upper Permian carbonate platform, Capitan margin of northern Delaware basin

    SciTech Connect (OSTI)

    Harris, P.M.; Grover, G.A.

    1989-03-01

    Subsurface and outcrop studies of the Capitan margin (late Guadalupian, Capitanian) in the northern Delaware basin have revealed that over 80% of the total progradation of the margin, over half the total aggradation of the platform (150 of 290 m), and over two-thirds of the basin fill (190 of 280 m) occurred during an early phase of development equating with Seven Rivers beds on the platform. The amount of progradation varied from 6 km from outcrop data in the Guadalupe Mountains to 19 km along trend to the east from subsurface information. The later phase of Capitan margin development was coincident with Yates and Tansill deposition on the platform and was dominated by aggradation and steepening of the margin. Corresponding to this two-phase model, two third-order cycles of relative sea level occur within the Capitanian on the eustasy curve of Ross and Ross: a Seven Rivers cycle lasting 1.5 m.y. and a Yates-Tansill cycle of 1.0 m.y. Progradation rates for the Capitan range from 2.6 to 8.3 m/1000 years. Similar rates are calculated from high-resolution seismic lines across the Cenozoic margin of northwestern great Bahama Bank. Accumulation rates for the Capitan, uncorrected for compaction, average 125 ..mu..m/year and 335 ..mu..m/year for the early phase shelf and shelf margin, respectively, and 160 ..mu..m/year and 430..mu..m/year for the later phase shelf and shelf margin. These accumulation rates are similar to those of other ancient, prograding platforms.

  4. A Rac1--GDP trimer complex binds zinc with tetrahedral and octahedral coordination, displacing magnesium

    SciTech Connect (OSTI)

    Prehna, G.; Stebbins, C

    2007-01-01

    The Rho family of small GTPases represent well characterized signaling molecules that regulate many cellular functions such as actin cytoskeletal arrangement and the cell cycle by acting as molecular switches. A Rac1-GDP-Zn complex has been crystallized in space group P3221 and its crystal structure has been solved at 1.9 {angstrom} resolution. These trigonal crystals reveal the unexpected ability of Rac1 to coordinate Zn atoms in a tetrahedral fashion by use of its biologically relevant switch I and switch II regions. Upon coordination of zinc, the switch I region is stabilized in the GDP-bound conformation and contributes to a Rac1 trimer in the asymmetric unit. Zinc coordination causes switch II to adopt a novel conformation with a symmetry-related molecule. Additionally, zinc was found to displace magnesium from its octahedral coordination at switch I, although GDP binding remained stable. This structure represents the first reported Rac1-GDP-Zn complex, which further underscores the conformational flexibility and versatility of the small GTPase switch regions.

  5. A Rac1-GDP Trimer Complex Binds Zinc with Tetrahedral and Octahedral Coordination, Displacing Magnesium

    SciTech Connect (OSTI)

    Prehna,G.; Stebbins, E.

    2007-01-01

    The Rho family of small GTPases represent well characterized signaling molecules that regulate many cellular functions such as actin cytoskeletal arrangement and the cell cycle by acting as molecular switches. A Rac1-GDP-Zn complex has been crystallized in space group P3{sub 2}21 and its crystal structure has been solved at 1.9 {angstrom} resolution. These trigonal crystals reveal the unexpected ability of Rac1 to coordinate Zn atoms in a tetrahedral fashion by use of its biologically relevant switch I and switch II regions. Upon coordination of zinc, the switch I region is stabilized in the GDP-bound conformation and contributes to a Rac1 trimer in the asymmetric unit. Zinc coordination causes switch II to adopt a novel conformation with a symmetry-related molecule. Additionally, zinc was found to displace magnesium from its octahedral coordination at switch I, although GDP binding remained stable. This structure represents the first reported Rac1-GDP-Zn complex, which further underscores the conformational flexibility and versatility of the small GTPase switch regions.

  6. The effect of pulse duration on the growth rate of laser-induced damage sites at 351 nm on fused silica surfaces

    SciTech Connect (OSTI)

    Negres, R A; Norton, M A; Liao, Z M; Cross, D A; Bude, J D; Carr, C W

    2009-10-29

    Past work in the area of laser-induced damage growth has shown growth rates to be primarily dependent on the laser fluence and wavelength. More recent studies suggest that growth rate, similar to the damage initiation process, is affected by a number of additional parameters including pulse duration, pulse shape, site size, and internal structure. In this study, we focus on the effect of pulse duration on the growth rate of laser damage sites located on the exit surface of fused silica optics. Our results demonstrate, for the first time, a significant dependence of growth rate at 351 nm on pulse duration from 1 ns to 15 ns as {tau}{sup 0.3} for sites in the 50-100 {micro}m size range.

  7. Impact of Pretreatment Tumor Growth Rate on Outcome of Early-Stage Lung Cancer Treated With Stereotactic Body Radiation Therapy

    SciTech Connect (OSTI)

    Atallah, Soha; Cho, B.C. John; Allibhai, Zishan; Taremi, Mojgan; Giuliani, Meredith; Le, Lisa W.; Brade, Anthony; Sun, Alexander; Bezjak, Andrea; Hope, Andrew J.

    2014-07-01

    Purpose: To determine the influence of pretreatment tumor growth rate on outcomes in patients with early-stage non-small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT). Methods and Materials: A review was conducted on 160 patients with T1-T2N0M0 NSCLC treated with SBRT at single institution. The patient's demographic and clinical data, time interval (t) between diagnostic and planning computed tomography (CT), vital status, disease status, and cause of death were extracted from a prospectively kept database. Differences in gross tumor volume between diagnostic CT (GTV1) and planning CT (GTV2) were recorded, and growth rate was calculated by use of specific growth rate (SGR). Kaplan-Meier curves were constructed for overall survival (OS). Differences between groups were compared with a log-rank test. Multivariate analyses were performed by use of the Cox proportional hazard model with SGR and other relevant clinical factors. Cumulative incidence was calculated for local, regional, and distant failures by use of the competing risk approach and was compared with Gray's test. Results: The median time interval between diagnostic and planning CT was 82 days. The patients were divided into 2 groups, and the median SGR was used as a cut-off. The median survival times were 38.6 and 27.7 months for the low and high SGR groups, respectively (P=.03). Eastern Cooperative Oncology Group performance status (P=.01), sex (P=.04), SGR (P=.03), and GTV2 (P=.002) were predictive for OS in multivariable Cox regression analysis and, except sex, were similarly predictive for failure-free survival (FFS). The 3-year cumulative incidences of regional failure were 19.2% and 6.0% for the high and low SGR groups, respectively (P=.047). Conclusion: High SGR was correlated with both poorer OS and FFS in patients with early-stage NSCLC treated with SBRT. If validated, this measurement may be useful in identifying patients most likely to benefit from adjuvant

  8. Exact analytical solution of the linear structure growth rate in {Lambda}CDM cosmology and its cosmological applications

    SciTech Connect (OSTI)

    Zhang Pengjie [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Science, 80 Nandan Road, Shanghai, China, 200030 (China)

    2011-03-15

    We derive the exact analytical solution of the linear structure growth rate in {Lambda}CDM cosmology with flat or curved geometry, under the Newtonian gauge. Unlike the well known solution under the Newtonian limit [D. J. Heath, Mon. Not. R. Astron. Soc. 179, 351 (1977)], our solution takes all general relativistic corrections into account and is hence valid at both the sub- and superhorizon scales. With this exact solution, we evaluate cosmological impacts induced by these relativistic corrections. (1) General relativistic corrections alter the density growth from z=100 to z=0 by 10% at k=0.01 h/Mpc and the impact becomes stronger toward larger scales. We caution the readers that the overdensity is not gauge invariant and the above statement is restrained to the Newtonian gauge. (2) Relativistic corrections introduce a k{sup -2} scale dependence in the density fluctuation. It mimics a primordial non-Gaussianity of the local type with f{sub NL}{sup local{approx}}1. This systematical error may become non-negligible for future all sky deep galaxy surveys. (3) Cosmological simulations with box size greater than 1 Gpc are also affected by these relativistic corrections. We provide a postprocessing recipe to correct for these effects. (4) These relativistic corrections affect the redshift distortion. However, at redshifts and scales relevant to redshift distortion measurements, such effect is negligible.

  9. Cloning, purification and preliminary crystallographic analysis of the Bacillus subtilis GTPase YphCGDP complex

    SciTech Connect (OSTI)

    Xu, Ling; Muench, Stephen P.; Roujeinikova, Anna; Sedelnikova, Svetlana E.; Rice, David W.

    2006-05-01

    Crystals of a selenomethionine-incorporated YphCGDP complex have been grown using the hanging-drop vapour-diffusion method and polyethylene glycol as a precipitating agent. The Bacillus subtilis YphC gene encodes an essential GTPase thought to be involved in ribosome binding and whose protein product may represent a target for the development of a novel antibacterial agent. Sequence analysis reveals that YphC belongs to the EngA family of GTPases, which uniquely contain two adjacent GTP-binding domains. Crystals of a selenomethionine-incorporated YphCGDP complex have been grown using the hanging-drop vapour-diffusion method and polyethylene glycol as a precipitating agent. The crystals belong to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 62.71, b = 65.05, c = 110.61 , and have one molecule in the asymmetric unit. Data sets at three different wavelengths were collected on a single crystal to 2.5 resolution at the Daresbury SRS in order to solve the structure by MAD. Ultimately, analysis of YphC in complex with GDP may allow a greater understanding of the EngA family of essential GTPases.

  10. Spectroscopic analysis of H{sub 2}/CH{sub 4} microwave plasma and fast growth rate of diamond single crystal

    SciTech Connect (OSTI)

    Derkaoui, N.; Rond, C. Hassouni, K.; Gicquel, A.

    2014-06-21

    One of the best ways to increase the diamond growth rate is to couple high microwave power to the plasma. Indeed, increasing the power density leads to increase gas temperature the atomic hydrogen density in the plasma bulk, and to produce more hydrogen and methyl at the diamond surface. Experimental and numerical approaches were used to study the microwave plasma under high power densities conditions. Gas temperature was measured by optical emission spectroscopy and H-atom density using actinometry. CH{sub 3}-radical density was obtained using a 1D model that describes temperatures and plasma composition from the substrate to the top of the reactor. The results show that gas temperature in the plasma bulk, atomic hydrogen, and methyl densities at the diamond surface highly increase with the power density. As a consequence, measurements have shown that diamond growth rate also increases. At very high power density, we measured a growth rate of 40??m/h with an H-atom density of 5 10{sup 17} cm{sup ?3} which corresponds to a H{sub 2} dissociation rate higher than 50%. Finally, we have shown that the growth rate can be framed between a lower and an upper limit as a function depending only on the maximum of H-atom density measured or calculated in the plasma bulk. The results also demonstrated that increasing fresh CH{sub 4} by an appropriate injection into the boundary layer is a potential way to increase the diamond growth rates.

  11. Improved Performance of GaInNAs Solar Cells Grown by Molecular-Beam Epitaxy Using Increased Growth Rate Instead of Surfactants

    SciTech Connect (OSTI)

    Ptak, A. J.; France, R.; Jiang, C. S.; Romero, M. J.

    2009-01-01

    GaInNAs is potentially useful for increasing the conversion efficiency of multijunction solar cells if low photocurrents and photovoltages can be increased. Wide-depletion width devices generate significant photocurrents using an n-i-p structure grown by molecular-beam epitaxy, but these wide depletion widths are only realized in a region of parameter space that leads to rough surface morphologies. Surfactants are effective at reducing the surface roughness, but lead to increased defect densities and changes in the net acceptor or donor concentration. Here, we show that increasing the growth rate of GaInNAs solar cells leads to smooth surfaces without the use of a surfactant, even at high In compositions and substrate temperatures. No degradation in material quality is observed when increasing the growth rate from 1.5 to 3.0 {micro}m/h, but a shunt resistance does appear for the high-growth-rate samples. This shunt is attributed to increased spitting of the Ga cell, leading to an increase in the oval defect density, at the higher effusion cell temperatures used to achieve high growth rates. As with the case of Bi in GaInNAs, increased growth rates also appear to increase the net donor concentration, but it is not clear if these effects have the same cause.

  12. Guidance for growth factors, projections, and control strategies for the 15 percent rate-of-progress plans

    SciTech Connect (OSTI)

    Not Available

    1993-03-01

    Section 182(b)(1) of the Clean Air Act (Act) requires all ozone nonattainment areas classified as moderate and above to submit a State Implementation Plan (SIP) revision by November 15, 1993, which describes, in part, how the areas will achieve an actual volatile organic compound (VOC) emissions reduction of at least 15 percent during the first 6 years after enactment of the Clean Air Act Amendments of 1990 (CAAA). In addition, the SIP revision must describe how any growth in emissions from 1990 through 1996 will be fully offset. It is important to note that section 182(b)(1) also requires the SIP for moderate areas to provide for reductions in VOC and nitrogen oxides (NOx) emissions as necessary to attain the national primary ambient air quality standard for ozone by November 15, 1996. The guidance document focuses on the procedures for developing 1996 projected emissions inventories and control measures which moderate and above ozone nonattainment areas must include in their rate-of-progress plans. The document provides technical guidance to support the policy presented in the 'General Preamble: Implementation of Title I of the CAAA of 1990' (57 FR 13498).

  13. Difference in C3–C4 metabolism underlies tradeoff between growth rate and biomass yield in Methylobacterium extorquens AM1

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

    Fu, Yanfen; Beck, David A. C.; Lidstrom, Mary E.

    2016-07-19

    In this study, two variants of Methylobacterium extorquens AM1 demonstrated a trade-off between growth rate and biomass yield. In addition, growth rate and biomass yield were also affected by supplementation of growth medium with different amounts of cobalt. The metabolism changes relating to these growth phenomena as well as the trade-off were investigated in this study. 13C metabolic flux analysis was used to generate a detailed central carbon metabolic flux map with both absolute and normalized flux values. As a result, the major differences between the two variants occurred at the formate node as well as within C3-C4 inter-conversion pathways.more » Higher relative fluxes through formyltetrahydrofolate ligase, phosphoenolpyruvate carboxylase, and malic enzyme led to higher biomass yield, while higher relative fluxes through pyruvate kinase and pyruvate dehydrogenase led to higher growth rate. These results were then tested by phenotypic studies on three mutants (null pyk, null pck mutant and null dme mutant) in both variants, which agreed with the model prediction. In this study, 13C metabolic flux analysis for two strain variants of M. extorquens AM1 successfully identified metabolic pathways contributing to the trade-off between cell growth and biomass yield. Phenotypic analysis of mutants deficient in corresponding genes supported the conclusion that C3-C4 inter-conversion strategies were the major response to the trade-off.« less

  14. Effects of zinc additions on the stress corrosion crack growth rate of sensitized stainless steel, Alloy 600 and Alloy 182 weld metal in 288 C water

    SciTech Connect (OSTI)

    Andresen, P.L.; Angeliu, T.M.

    1995-09-01

    ZnO additions to boiling water reactor (BWR) water have been the focus of recent interest, primarily because of their beneficial influence in reducing buildup of radioactive species such as Co{sup 60} in the oxide film of structural components, e.g., stainless steel piping. The effect of ZnO additions on stress corrosion crack growth rates were studied using 1T CT fracture mechanics specimens of sensitized type 304 stainless steel, sensitized Alloy 600, and Alloy 182 weld metal exposed to {approx}288 C water containing various levels of dissolved oxygen and impurities. Zn levels of 5 to 100 ppb Zn{sup 2+} were evaluated and found to reduce crack growth rates for all materials and in all water chemistries. Many Zn tests involved long term exposure and were performed at somewhat reduced corrosion potential (e.g., from {approx}+200 to 0 {minus}+50 mV{sub she}); variations in corrosion potential from +200, to +50, to {minus}50 mV{sub she} clearly had an important effect. The benefit of Zn appeared to be most pronounced when the growth rate was decreased (e.g., by corrosion potential). This was consistent with the findings of mechanistic studies, which showed that Zn decreased the repassivation response at times >10{sup 4} s, which is associated with low crack tip strain rates, i.e., low growth rates. Reduced corrosion potentials are also expected to directly effect Zn, since high (crack mouth) corrosion potentials inhibit the transport of Zn{sup 2+} into the crack. Zn also increased the fracture strain of the oxide on stainless steel, and may also reduce crack growth rates by increasing the pH in the crack. Similar benefits are expected for other structural materials, such as nonsensitized or irradiated stainless steel, carbon steel, low alloy steel, and other nickel alloys.

  15. A cosmological exclusion plot: towards model-independent constraints on modified gravity from current and future growth rate data

    SciTech Connect (OSTI)

    Taddei, Laura

    2015-02-01

    Most cosmological constraints on modified gravity are obtained assuming that the cosmic evolution was standard ΛCDM in the past and that the present matter density and power spectrum normalization are the same as in a ΛCDM model. Here we examine how the constraints change when these assumptions are lifted. We focus in particular on the parameter Y (also called G{sub eff}) that quantifies the deviation from the Poisson equation. This parameter can be estimated by comparing with the model-independent growth rate quantity fσ{sub 8}(z) obtained through redshift distortions. We reduce the model dependency in evaluating Y by marginalizing over σ{sub 8} and over the initial conditions, and by absorbing the degenerate parameter Ω{sub m,0} into Y. We use all currently available values of fσ{sub 8}(z). We find that the combination Y-circumflex =YΩ{sub m,0}, assumed constant in the observed redshift range, can be constrained only very weakly by current data, Y-circumflex =0.28{sub −0.23}{sup +0.35} at 68% c.l. We also forecast the precision of a future estimation of Y-circumflex in a Euclid-like redshift survey. We find that the future constraints will reduce substantially the uncertainty, Y-circumflex =0.30{sub −0.09}{sup +0.08} , at 68% c.l., but the relative error on Y-circumflex around the fiducial remains quite high, of the order of 30%. The main reason for these weak constraints is that Y-circumflex is strongly degenerate with the initial conditions, so that large or small values of Y-circumflex are compensated by choosing non-standard initial values of the derivative of the matter density contrast. Finally, we produce a forecast of a cosmological exclusion plot on the Yukawa strength and range parameters, which complements similar plots on laboratory scales but explores scales and epochs reachable only with large-scale galaxy surveys. We find that future data can constrain the Yukawa strength to within 3% of the Newtonian one if the range is around a few

  16. Structural basis of GDP release and gating in G protein coupled Fe[superscript 2+] transport

    SciTech Connect (OSTI)

    Guilfoyle, Amy; Maher, Megan J.; Rapp, Mikaela; Clarke, Ronald; Harrop, Stephen; Jormakka, Mika

    2009-09-29

    G proteins are key molecular switches in the regulation of membrane protein function and signal transduction. The prokaryotic membrane protein FeoB is involved in G protein coupled Fe{sup 2+} transport, and is unique in that the G protein is directly tethered to the membrane domain. Here, we report the structure of the soluble domain of FeoB, including the G protein domain, and its assembly into an unexpected trimer. Comparisons between nucleotide free and liganded structures reveal the closed and open state of a central cytoplasmic pore, respectively. In addition, these data provide the first observation of a conformational switch in the nucleotide-binding G5 motif, defining the structural basis for GDP release. From these results, structural parallels are drawn to eukaryotic G protein coupled membrane processes.

  17. DEMONSTRATING SLOW GROWTH RATES IN OPAL FROM Y.M.,NV, USING MICRODIGESTION AND ION-PROBE URANIUM-SERIES DATING

    SciTech Connect (OSTI)

    J. PACES; L. NEYMARK; H. PERSING; J. WOODEN

    2000-07-25

    Thinly laminated (<0.01 mm) opal sheets and globules associated with calcite in fractures and cavities in the unsaturated zone at Yucca Mountain, Nevada, have U concentrations of 50 to 300 ppm. Previous uranium-series thermal ionization mass spectrometry (TIMS) analyses of 0.2- to 1-mm-thick subsamples resulted in a model of slow mineral growth at rates of 0.5 to 5 mm/m.y. To test this growth model using finer sampling resolution, in situ microdigestions were performed by applying a drop of hydrofluoric acid directly to opal surfaces within a small area encircled by jeweler's wax. After several minutes, the liquid was removed, spiked with a tracer solution, and analyzed by TIMS for both U and Th using a single rhenium filament with colloidal graphite. Solutions contained about 0.5 nanograms of U, equivalent to opal weights of 1 to 10 micrograms and dissolved-layer thicknesses less than 0.003 mm. Microdigested opal surfaces have Th-230/U ages of 5 to 10 thousand years (ka) in contrast to much older ages of 150 to 250 ka obtained previously from whole-globule digestions. Additional tests of the growth model were made on cross sections of identical opal globules using the sensitive high-resolution ion microprobe (SHRIMP) with a 0.04-mm-diameter O-minus primary beam. Counting rates for Tho-246 and U-234 varied between 5 and 70 counts per second with Th-230/Th-232 activity ratios typically much greater than a million. The Th-230/U ages in the outer 0.3 mm of the globules ranged from about 30 ka at the outer edge to 400 ka at depth. Ages correlate with microstratigraphic depths and indicate average growth rates between 0.5 and 0.7 mm/m.y. Current U-series data do not resolve differential growth rates related to climate changes during this time period. However, both microdigestion and SHRIMP results confirm the previous TIMS-based model of slow, uniform rates of mineral growth in a hydrologically stable environment.

  18. ENHANCED GROWTH RATE AND SILANE UTILIZATION IN AMORPHOUS SILICON AND NANOCRYSTALLINE-SILICON SOLAR CELL DEPOSITION VIA GAS PHASE ADDITIVES

    SciTech Connect (OSTI)

    Ridgeway, R.G.; Hegedus, S.S.; Podraza, N.J.

    2012-08-31

    Air Products set out to investigate the impact of additives on the deposition rate of both µCSi and αSi-H films. One criterion for additives was that they could be used in conventional PECVD processing, which would require sufficient vapor pressure to deliver material to the process chamber at the required flow rates. The flow rate required would depend on the size of the substrate onto which silicon films were being deposited, potentially ranging from 200 mm diameter wafers to the 5.7 m2 glass substrates used in GEN 8.5 flat-panel display tools. In choosing higher-order silanes, both disilane and trisilane had sufficient vapor pressure to withdraw gas at the required flow rates of up to 120 sccm. This report presents results obtained from testing at Air Products’ electronic technology laboratories, located in Allentown, PA, which focused on developing processes on a commercial IC reactor using silane and mixtures of silane plus additives. These processes were deployed to compare deposition rates and film properties with and without additives, with a goal of maximizing the deposition rate while maintaining or improving film properties.

  19. Determination of redox reaction rates and orders by in-situ liquid cell electron microscopy of Pd and Au solution growth

    SciTech Connect (OSTI)

    Sutter, Eli A.; Sutter, Peter W.

    2014-11-19

    In-situ liquid cell transmission and scanning transmission electron microscopy (TEM/STEM) experiments are important as they provide direct insight into processes in liquids, such as solution growth of nanoparticles among others. In liquid cell TEM/STEM redox reaction experiments the hydrated electrons e?aq created by the electron beam are responsible for the reduction of metal-ion complexes. Here we investigate the rate equation of redox reactions involving reduction by e?aq generated by the electron beam during in-situ liquid TEM/STEM. Specifically we consider the growth of Pd on Au seeds in aqueous solutions containing Pd-chloro complexes. From the quantification of the rate of Pd deposition at different electron beam currents and as a function of distance from a stationary, nanometer-sized exciting beam, we determine that the reaction is first order with respect to the concentration of hydrated electrons, [e?aq]. By comparing Pd- and Au-deposition, we further demonstrate that measurements of the local deposition rate on nanoparticles in the solution via real-time imaging can be used to measure not only [e?aq] but also the rate of reduction of a metal-ion complex to zero-valent metal atoms in solution.

  20. Mutational, Structural, and Kinetic Evidence for a Dissociative Mechanism in the GDP-mannose Mannosyl Hydrolase Reaction

    SciTech Connect (OSTI)

    Xia,Z.; Azurmendi, H.; lairson, L.; Withers, S.; Gabelli, S.; Bianchet, M.; Amzel, L.; Mildvan, A.

    2005-01-01

    GDP-mannose hydrolase (GDPMH) catalyzes the hydrolysis of GDP-{alpha}-D-sugars by nucleophilic substitution with inversion at the anomeric C1 atom of the sugar, with general base catalysis by H124. Three lines of evidence indicate a mechanism with dissociative character. First, in the 1.3 Angstrom X-ray structure of the GDPMH-Mg{sup 2+}-GDP{center_dot}Tris{sup +} complex, the GDP leaving group interacts with five catalytic components: R37, Y103, R52, R65, and the essential Mg{sup 2+}. As determined by the effects of site-specific mutants on k{sub cat}, these components contribute factors of 24-, 100-, 309-, 24-, and {ge}10{sup 5}-fold, respectively, to catalysis. Both R37 and Y103 bind the {beta}-phosphate of GDP and are only 5.0 Angstroms apart. Accordingly, the R37Q/Y103F double mutant exhibits partially additive effects of the two single mutants on k{sub cat}, indicating cooperativity of R37 and Y103 in promoting catalysis, and antagonistic effects on K{sub m}. Second, the conserved residue, D22, is positioned to accept a hydrogen bond from the C2-OH group of the sugar undergoing substitution at C1, as was shown by modeling an {alpha}-D-mannosyl group into the sugar binding site. The D22A and D22N mutations decreased k{sub cat} by factors of 10{sup 2.1} and 10{sup 2.6}, respectively, for the hydrolysis of GDP-{alpha}-D-mannose, and showed smaller effects on K{sub m}, suggesting that the D22 anion stabilizes a cationic oxocarbenium transition state. Third, the fluorinated substrate, GDP-2F-{alpha}-D-mannose, for which a cationic oxocarbenium transition state would be destabilized by electron withdrawal, exhibited a 16-fold decrease in k{sub cat} and a smaller, 2.5-fold increase in K{sub m}. The D22A and D22N mutations further decreased the k{sub cat} with GDP-2F-{alpha}-D-mannose to values similar to those found with GDP-{alpha}-D-mannose, and decreased the K{sub m} of the fluorinated substrate. The choice of histidine as the general base over glutamate, the

  1. Determination of crystal growth rates during rapid solidification of polycrystalline aluminum by nano-scale spatio-temporal resolution in situ transmission electron microscopy

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

    Zweiacker, K.; McKeown, J. T.; Liu, C.; LaGrange, T.; Reed, B. W.; Campbell, G. H.; Wiezorek, J. M. K.

    2016-08-04

    In situ investigations of rapid solidification in polycrystalline Al thin films were conducted using nano-scale spatio-temporal resolution dynamic transmission electron microscopy. Differences in crystal growth rates and asymmetries in melt pool development were observed as the heat extraction geometry was varied by controlling the proximity of the laser-pulse irradiation and the associated induced melt pools to the edge of the transmission electron microscopy support grid, which acts as a large heat sink. Experimental parameters have been established to maximize the reproducibility of the material response to the laser-pulse-related heating and to ensure that observations of the dynamical behavior of themore » metal are free from artifacts, leading to accurate interpretations and quantifiable measurements with improved precision. Interface migration rate measurements revealed solidification velocities that increased consistently from ~1.3 m s–1 to ~2.5 m s–1 during the rapid solidification process of the Al thin films. Under the influence of an additional large heat sink, increased crystal growth rates as high as 3.3 m s–1 have been measured. The in situ experiments also provided evidence for development of a partially melted, two-phase region prior to the onset of rapid solidification facilitated crystal growth. As a result, using the experimental observations and associated measurements as benchmarks, finite-element modeling based calculations of the melt pool evolution after pulsed laser irradiation have been performed to obtain estimates of the temperature evolution in the thin films.« less

  2. Helix Dipole Movement and Conformational Variability Contribute to Allosteric GDP Release in G[alpha] Subunits

    SciTech Connect (OSTI)

    Preininger, Anita M.; Funk, Michael A.; Oldham, William M.; Meier, Scott M.; Johnston, Christopher A.; Adhikary, Suraj; Kimple, Adam J.; Siderovski, David P.; Hamm, Heidi E.; Iverson, Tina M.

    2009-06-01

    Heterotrimeric G proteins (Galphabetagamma) transmit signals from activated G protein-coupled receptors (GPCRs) to downstream effectors through a guanine nucleotide signaling cycle. Numerous studies indicate that the carboxy-terminal alpha5 helix of Galpha subunits participates in Galpha-receptor binding, and previous EPR studies suggest this receptor-mediated interaction induces a rotation and translation of the alpha5 helix of the Galpha subunit [Oldham, W. M., et al. (2006) Nat. Struct. Mol. Biol. 13, 772-777]. On the basis of this result, an engineered disulfide bond was designed to constrain the alpha5 helix of Galpha(i1) into its EPR-measured receptor-associated conformation through the introduction of cysteines at position 56 in the alpha1 helix and position 333 in the alpha5 helix (I56C/Q333C Galpha(i1)). A functional mimetic of the EPR-measured alpha5 helix dipole movement upon receptor association was additionally created by introduction of a positive charge at the amino terminus of this helix, D328R Galpha(i1). Both proteins exhibit a dramatically elevated level of basal nucleotide exchange. The 2.9 A resolution crystal structure of I56C/Q333C Galpha(i1) in complex with GDP-AlF(4)(-) reveals the shift of the alpha5 helix toward the guanine nucleotide binding site that is anticipated by EPR measurements. The structure of the I56C/Q333C Galpha(i1) subunit further revealed altered positions for the switch regions and throughout the Galpha(i1) subunit, accompanied by significantly elevated crystallographic temperature factors. Combined with previous evidence in the literature, the structural analysis supports the critical role of electrostatics of the alpha5 helix dipole and overall conformational variability during nucleotide release.

  3. Approximate models for the study of exponential changed quantities: Application on the plasma waves growth rate or damping

    SciTech Connect (OSTI)

    Xaplanteris, C. L.; Xaplanteris, L. C.; Leousis, D. P.

    2014-03-15

    Many physical phenomena that concern the research these days are basically complicated because of being multi-parametric. Thus, their study and understanding meets with big if not unsolved obstacles. Such complicated and multi-parametric is the plasmatic state as well, where the plasma and the physical quantities that appear along with it have chaotic behavior. Many of those physical quantities change exponentially and at most times they are stabilized by presenting wavy behavior. Mostly in the transitive state rather than the steady state, the exponentially changing quantities (Growth, Damping etc) depend on each other in most cases. Thus, it is difficult to distinguish the cause from the result. The present paper attempts to help this difficult study and understanding by proposing mathematical exponential models that could relate with the study and understanding of the plasmatic wavy instability behavior. Such instabilities are already detected, understood and presented in previous publications of our laboratory. In other words, our new contribution is the study of the already known plasmatic quantities by using mathematical models (modeling and simulation). These methods are both useful and applicable in the chaotic theory. In addition, our ambition is to also conduct a list of models useful for the study of chaotic problems, such as those that appear into the plasma, starting with this paper's examples.

  4. Structure of the protein core of translation initiation factor 2 in apo, GTP-bound and GDP-bound forms

    SciTech Connect (OSTI)

    Simonetti, Angelita; Fabbretti, Attilio; Hazemann, Isabelle; Jenner, Lasse; Gualerzi, Claudio O.; Klaholz, Bruno P.

    2013-06-01

    The crystal structures of the eubacterial translation initiation factor 2 in apo form and with bound GDP and GTP reveal conformational changes upon nucleotide binding and hydrolysis, notably of the catalytically important histidine in the switch II region. Translation initiation factor 2 (IF2) is involved in the early steps of bacterial protein synthesis. It promotes the stabilization of the initiator tRNA on the 30S initiation complex (IC) and triggers GTP hydrolysis upon ribosomal subunit joining. While the structure of an archaeal homologue (a/eIF5B) is known, there are significant sequence and functional differences in eubacterial IF2, while the trimeric eukaryotic IF2 is completely unrelated. Here, the crystal structure of the apo IF2 protein core from Thermus thermophilus has been determined by MAD phasing and the structures of GTP and GDP complexes were also obtained. The IF2GTP complex was trapped by soaking with GTP in the cryoprotectant. The structures revealed conformational changes of the protein upon nucleotide binding, in particular in the P-loop region, which extend to the functionally relevant switch II region. The latter carries a catalytically important and conserved histidine residue which is observed in different conformations in the GTP and GDP complexes. Overall, this work provides the first crystal structure of a eubacterial IF2 and suggests that activation of GTP hydrolysis may occur by a conformational repositioning of the histidine residue.

  5. Crack growth rates and metallographic examinations of Alloy 600 and Alloy 82/182 from field components and laboratory materials tested in PWR environments.

    SciTech Connect (OSTI)

    Alexandreanu, B.; Chopra, O. K.; Shack, W. J.

    2008-05-05

    In light water reactors, components made of nickel-base alloys are susceptible to environmentally assisted cracking. This report summarizes the crack growth rate results and related metallography for field and laboratory-procured Alloy 600 and its weld alloys tested in pressurized water reactor (PWR) environments. The report also presents crack growth rate (CGR) results for a shielded-metal-arc weld of Alloy 182 in a simulated PWR environment as a function of temperature between 290 C and 350 C. These data were used to determine the activation energy for crack growth in Alloy 182 welds. The tests were performed by measuring the changes in the stress corrosion CGR as the temperatures were varied during the test. The difference in electrochemical potential between the specimen and the Ni/NiO line was maintained constant at each temperature by adjusting the hydrogen overpressure on the water supply tank. The CGR data as a function of temperature yielded activation energies of 252 kJ/mol for a double-J weld and 189 kJ/mol for a deep-groove weld. These values are in good agreement with the data reported in the literature. The data reported here and those in the literature suggest that the average activation energy for Alloy 182 welds is on the order of 220-230 kJ/mol, higher than the 130 kJ/mol commonly used for Alloy 600. The consequences of using a larger value of activation energy for SCC CGR data analysis are discussed.

  6. Sphere-Shaped Hierarchical Cathode with Enhanced Growth of Nanocrystal Planes for High-Rate and Cycling-Stable Li-Ion Batteries

    SciTech Connect (OSTI)

    Zhang, Linjing; Li, Ning; Wu, Borong; Xu, Hongliang; Wang, Lei; Yang, Xiao-Qing; Wu, Feng

    2015-01-14

    High-energy and high-power Li-ion batteries have been intensively pursued as power sources in electronic vehicles and renewable energy storage systems in smart grids. With this purpose, developing high-performance cathode materials is urgently needed. Here we report an easy and versatile strategy to fabricate high-rate and cycling-stable hierarchical sphered cathode Li1.2Ni0.13Mn0.54Co0.13O2, by using an ionic interfusion method. The sphere-shaped hierarchical cathode is assembled with primary nanoplates with enhanced growth of nanocrystal planes in favor of Li+ intercalation/deintercalation, such as (010), (100), and (110) planes. This material with such unique structural features exhibits outstanding rate capability, cyclability, and high discharge capacities, achieving around 70% (175 mAhg–1) of the capacity at 0.1 C rate within about 2.1 min of ultrafast charging. Such cathode is feasible to construct high-energy and high-power Li-ion batteries.

  7. Sphere-Shaped Hierarchical Cathode with Enhanced Growth of Nanocrystal Planes for High-Rate and Cycling-Stable Li-Ion Batteries

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

    Zhang, Linjing; Li, Ning; Wu, Borong; Xu, Hongliang; Wang, Lei; Yang, Xiao-Qing; Wu, Feng

    2015-01-14

    High-energy and high-power Li-ion batteries have been intensively pursued as power sources in electronic vehicles and renewable energy storage systems in smart grids. With this purpose, developing high-performance cathode materials is urgently needed. Here we report an easy and versatile strategy to fabricate high-rate and cycling-stable hierarchical sphered cathode Li1.2Ni0.13Mn0.54Co0.13O2, by using an ionic interfusion method. The sphere-shaped hierarchical cathode is assembled with primary nanoplates with enhanced growth of nanocrystal planes in favor of Li+ intercalation/deintercalation, such as (010), (100), and (110) planes. This material with such unique structural features exhibits outstanding rate capability, cyclability, and high discharge capacities, achievingmore » around 70% (175 mAhg–1) of the capacity at 0.1 C rate within about 2.1 min of ultrafast charging. Such cathode is feasible to construct high-energy and high-power Li-ion batteries.« less

  8. Effects of pH and stress intensity on crack growth rate in Alloy 600 in lithiated + borated water at high temperatures

    SciTech Connect (OSTI)

    Rebak, R.B.; Szklarska-Smialowska, Z.; McIlree, A.R.

    1992-12-31

    Primary water stress corrosion cracking studies were performed on Alloy 600. Constant load tests were conducted at 330 and 350{degrees}C in solutions containing dissolved hydrogen, boric acid (0 < B < 1200 ppm) and lithium hydroxide (0 < Li < 10 ppm). In the PWR working conditions range, that is, 6.9 < pH < 7.4 (or 0.5 ppm < Li < 3.5), there is little effect of the solution pH on the intergranular crack growth rate (IGSCC). However, there is a strong influence of the stress intensity on the IGSCC. K{sub ISCC} {approx} 5-10 MPa{radical}m. Dissolution plays an important role in the IGSCC process.

  9. Tracing the mass growth and star formation rate evolution of massive galaxies from Z ∼ 6 to Z ∼ 1 in the Hubble ultra-deep field

    SciTech Connect (OSTI)

    Lundgren, Britt F.; Van Dokkum, Pieter; Oesch, Pascal; Franx, Marijn; Labbe, Ivo; Bouwens, Rychard; Trenti, Michele; Gonzalez, Valentino; Illingworth, Garth; Magee, Daniel

    2014-01-01

    We present an analysis of an H {sub 160}-selected photometric catalog of galaxies in the Hubble Ultra-Deep Field, using imaging from the WFC3/IR camera on the Hubble Space Telescope in combination with archival ultraviolet, optical, and near-infrared imaging. Using these data, we measure the spectral energy distributions of ∼1500 galaxies to a limiting H {sub 160} magnitude of 27.8, from which we fit photometric redshifts and stellar population estimates for all galaxies with well-determined Spitzer IRAC fluxes, allowing for the determination of the cumulative mass function within the range 1 < z < 6. By selecting samples of galaxies at a constant cumulative number density, we are able to explore the coevolution of stellar masses and star formation rates (SFRs) for progenitor galaxies and their descendants from z ∼ 6. We find a steady increase in the SFRs of galaxies at constant number density from z ∼ 6 to z ∼ 3, accompanied by gradually declining specific star formation rates (sSFRs) during this same period. The peak epoch of star formation is also found to shift to later times for galaxies with increasing number densities, in agreement with the expectations from cosmic downsizing. The observed SFRs can fully account for the mass growth to z ∼ 2 among galaxies with cumulative number densities greater than 10{sup –3.5} Mpc{sup –3}. For galaxies with a lower constant number density (higher mean mass), we find the observed stellar masses are ∼three times greater than that which may be accounted for by the observed star formation alone at late times, implying that growth from mergers plays an important role at z < 2. We additionally observe a decreasing sSFR, equivalent to approximately one order of magnitude, from z ∼ 6 to z ∼ 2 among galaxies with number densities less than 10{sup –3.5} Mpc{sup –3}, along with significant evidence that at any redshift the sSFR is higher for galaxies at higher number density. The combination of these findings

  10. The effect of in-situ noble metal chemical addition on crack growth rate behavior of structural materials in 288 C water

    SciTech Connect (OSTI)

    Andresen, P.L.; Angeliu, T.

    1996-10-01

    Stress corrosion cracking (SCC), especially in existing boiling water reactor (BVM) components, is most effectively accomplished by reducing the corrosion potential. This was successfully demonstrated by adding hydrogen to BNM water, which reduced oxidant concentration and corrosion potential by recombining with the radiolytically formed oxygen and hydrogen peroxide. However, reduction in the corrosion potential for some vessel internals is difficult, and others require high hydrogen addition rates, which results in an increase in the main steam radiation level from volatile N{sup 16}. Noble metal electrocatalysis provides a unique opportunity to efficiently achieve a dramatic reduction in corrosion potential and SCC in BWRs, by catalytically reacting all oxidants that diffuse to a (catalytic) metal surface with hydrogen. There are many techniques for creating catalytic surfaces, including alloying with noble metals or applying noble metal alloy powders to existing BWR components by thermal spraying or weld cladding. A novel system-wide approach for producing catalytic surfaces on all wetted components has been developed which employs the reactor coolant water as the medium of transport. This approach is termed in-situ noble metal chemical addition (NMCA), and has been successfully used in extensive laboratory tests to coat a wide range of pre-oxidized structural materials. In turn, these specimens have maintained catalytic response in long term, cyclic exposures to extremes in dissolved gases, impurity levels, pH, flow rate, temperature, straining, etc. With stoichiometric excess H{sub 2}, the corrosion potential drops dramatically and crack initiation and growth are greatly reduced, even at high O{sub 2} or H{sub 2}O{sub 2} levels. Without excess H{sub 2} (i.e., in normal BWR water chemistry), noble metals do not increase the corrosion potential or SCC.

  11. Siting algae cultivation facilities for biofuel production in the United States: trade-offs between growth rate, site constructability, water availability, and infrastructure

    SciTech Connect (OSTI)

    Venteris, Erik R.; McBride, Robert; Coleman, Andre M.; Skaggs, Richard; Wigmosta, Mark S.

    2014-02-21

    Locating sites for new algae cultivation facilities is a complex task. The climate must support high growth rates, and cultivation ponds require appropriate land and water resources as well as key utility and transportation infrastructure. We employ our spatiotemporal Biomass Assessment Tool (BAT) to select promising locations based on the open-pond cultivation of Arthrospira sp. and a strain of the order Desmidiales. 64,000 potential sites across the southern United States were evaluated. We progressively apply a range of screening criteria and track their impact on the number of selected sites, geographic location, and biomass productivity. Both strains demonstrate maximum productivity along the Gulf of Mexico coast, with the highest values on the Florida peninsula. In contrast, sites meeting all selection criteria for Arthrospira were located along the southern coast of Texas and for Desmidiales were located in Louisiana and southern Arkansas. Site selection was driven mainly by the lack of oil pipeline access in Florida and elevated groundwater salinity in southern Texas. The requirement for low salinity freshwater (<400 mg L-1) constrained Desmidiales locations; siting flexibility is greater for salt-tolerant species such as Arthrospira. Combined siting factors can result in significant departures from regions of maximum productivity but are within the expected range of site-specific process improvements.

  12. The Structure of the MUR1 GDP-mannose 4,67-deydratase from A. thaliana: Implications for Ligand Binding Specificity

    SciTech Connect (OSTI)

    Mulichak, A.M.; Bonin, C.P.; Reiter, W.-D.; Garavito, R.M.

    2010-03-08

    GDP-D-mannose 4,6-dehydratase catalyzes the first step in the de novo synthesis of GDP-L-fucose, the activated form of L-fucose, which is a component of glycoconjugates in plants known to be important to the development and strength of stem tissues. We have determined the three-dimensional structure of the MUR1 dehydratase isoform from Arabidopsis thaliana complexed with its NADPH cofactor as well as with the ligands GDP and GDP-D-rhamnose. MUR1 is a member of the nucleoside-diphosphosugar modifying subclass of the short-chain dehydrogenase/reductase enzyme family, having homologous structures and a conserved catalytic triad of Lys, Tyr, and Ser/Thr residues. MUR1 is the first member of this subfamily to be observed as a tetramer, the interface of which reveals a close and intimate overlap of neighboring NADP{sup +}-binding sites. The GDP moiety of the substrate also binds in an unusual syn conformation. The protein-ligand interactions around the hexose moiety of the substrate support the importance of the conserved triad residues and an additional Glu side chain serving as a general base for catalysis. Phe and Arg side chains close to the hexose ring may serve to confer substrate specificity at the O2 position. In the MUR1/GDP-D-rhamnose complex, a single unique monomer within the protein tetramer that has an unoccupied substrate site highlights the conformational changes that accompany substrate binding and may suggest the existence of negative cooperativity in MUR1 function.

  13. Stress Corrosion Crack Growth Rate Testing and Analytical Electron Microscopy of Alloy 600 as a Function of Pourbaix Space and Microstructure

    SciTech Connect (OSTI)

    N. Lewis; S.A. Attanasio; D.S. Morton; G.A. Young

    2000-10-04

    Stress corrosion crack (SCC) growth rate tests and analytical electron microscopy (AEM) studies were performed over a broad range of environments and heat treatments of Alloy 600. This effort was conducted to correlate bulk environmental conditions such as pH and electrochemical potential (EcP) with the morphology of the SCC crack. Development of a library of AEM morphologies formed by SCC in different environments is an important step in identifying the conditions that lead to SCC in components. Additionally, AEM examination of stress corrosion cracks formed in different environments and microstructures lends insight into the mechanism(s) of stress corrosion cracking. Testing was conducted on compact tension specimens in three environments: a mildly acidic oxidizing environment containing sulfate ions, a caustic environment containing 10% NaOH, and hydrogenated near-neutral buffered water. Additionally, stress corrosion cracking testing of a smooth specimen was conducted in hydrogenated steam. The following heat treatments of Alloy 600 were examined: mill annealed at 980 C (near-neutral water), mill annealed at 1010 C (steam), sensitized (acid and caustic), and mill annealed + healed to homogenize the grain boundary Cr concentration (caustic). Crack growth rate (CGR) testing showed that sensitized Alloy 600 tested in the mildly acidic, oxidizing environment containing sulfate ions produced the fastest cracking ({approx} 8.8 {micro}m/hr at 260 C), and AEM examination revealed evidence of sulfur segregation to the crack tip. The caustic environment produced slower cracking ({approx} 0.4 {micro}m/hr at 307 C) in the mill annealed + healed heat treatment but no observed cracking in the sensitized condition. In the caustic environment, fully oxidized carbides were present in the crack wake but not ahead of the crack tip. In near-neutral buffered water at 338 C, the CGR was a function of dissolved hydrogen in the water and exhibited a maximum (0.17 {micro}m/hr) near the

  14. Novel protein and Mg[superscript 2+] configurations in the Mg[superscript 2+] GDP Complex of the SRP GTPase ffh

    SciTech Connect (OSTI)

    Focia, Pamela J.; Alam, Hena; Lu, Thanh; Ramirez, Ursula D.; Freymann, Douglas M.

    2010-03-05

    Ffh is the signal sequence recognition and targeting subunit of the prokaryotic signal recognition particle (SRP). Previous structural studies of the NG GTPase domain of Ffh demonstrated magnesium-dependent and magnesium-independent binding conformations for GDP and GMPPNP that are believed to reflect novel mechanisms for exchange and activation in this member of the GTPase superfamily. The current study of the NG GTPase bound to Mg{sup 2+} GDP reveals two new binding conformations - in the first the magnesium interactions are similar to those seen previously, however, the protein undergoes a conformational change that brings a conserved aspartate into its second coordination sphere. In the second, the protein conformation is similar to that seen previously, but the magnesium coordination sphere is disrupted so that only five oxygen ligands are present. The loss of the coordinating water molecule, at the position that would be occupied by the oxygen of the {gamma}-phosphate of GTP, is consistent with that position being privileged for exchange during phosphate release. The available structures of the GDP-bound protein provide a series of structural snapshots that illuminate steps along the pathway of GDP release following GTP hydrolysis.

  15. The impact of monolayer coverage, barrier thickness and growth rate on the thermal stability of photoluminescence of coupled InAs/GaAs quantum dot hetero-structure with quaternary capping of InAlGaAs

    SciTech Connect (OSTI)

    Mandal, A.; Verma, U.; Halder, N.; Chakrabarti, S.

    2012-03-15

    Highlight: Black-Right-Pointing-Pointer Coupled InAs/GaAs MQDs with (In{sub 0.21}Al{sub 0.21}Ga{sub 0.58}As + GaAs) caps are considered. Black-Right-Pointing-Pointer Monolayer coverage, barrier thickness and growth rate of the dots are the factors. Black-Right-Pointing-Pointer PL peaks for the samples are within 1.1-1.3 {mu}m; significant for IBSCs and lasers. Black-Right-Pointing-Pointer NPTP (non-resonant multi-phonon assisted tunneling process) effect on FWHM of PL. -- Abstract: The self-assembled InAs/GaAs MQDs are widely investigated for their potential application in optoelectronic devices like lasers and photovoltaics. We have explored the effect of QD growth rate and structural parameters like capping layer thickness on the morphology and optical properties of the MQD heterostructures overgrown with a combination capping of InAlGaAs and GaAs. The growth rate of the seed layers in the MQD samples is also varied to investigate its effect in the vertical stacking of the islands. The change in the morphology and the optical properties of the samples due to variation in growth and structural parameters are explained by the presence of strain in the QD structures, which arises due to lattice mismatch.

  16. Structural Studies of the Nudix GDP-mannose Hydrolase from E. coli Reveals a New Motif for Mannose Recognition

    SciTech Connect (OSTI)

    A Boto; W Xu; J Jakoncic; A Pannuri; T Romeo; M Bessman; S Gabelli; L Amzel

    2011-12-31

    The Nudix hydrolase superfamily, characterized by the presence of the signature sequence GX5EX7REUXEEXGU (where U is I, L, or V), is a well-studied family in which relations have been established between primary sequence and substrate specificity for many members. For example, enzymes that hydrolyze the diphosphate linkage of ADP-ribose are characterized by having a proline 15 amino acids C-terminal of the Nudix signature sequence. GDPMK is a Nudix enzyme that conserves this characteristic proline but uses GDP-mannose as the preferred substrate. By investigating the structure of the GDPMK alone, bound to magnesium, and bound to substrate, the structural basis for this divergent substrate specificity and a new rule was identified by which ADP-ribose pyrophosphatases can be distinguished from purine-DP-mannose pyrophosphatases from primary sequence alone. Kinetic and mutagenesis studies showed that GDPMK hydrolysis does not rely on a single glutamate as the catalytic base. Instead, catalysis is dependent on residues that coordinate the magnesium ions and residues that position the substrate properly for catalysis. GDPMK was thought to play a role in biofilm formation because of its upregulation in response to RcsC signaling; however, GDPMK knockout strains show no defect in their capacity of forming biofilms.

  17. Resource demand growth and sustainability due to increased world consumption

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

    Balatsky, Alexander V.; Balatsky, Galina I.; Borysov, Stanislav S.

    2015-03-20

    The paper aims at continuing the discussion on sustainability and attempts to forecast the impossibility of the expanding consumption worldwide due to the planet’s limited resources. As the population of China, India and other developing countries continue to increase, they would also require more natural and financial resources to sustain their growth. We coarsely estimate the volumes of these resources (energy, food, freshwater) and the gross domestic product (GDP) that would need to be achieved to bring the population of India and China to the current levels of consumption in the United States. We also provide estimations for potentially neededmore » immediate growth of the world resource consumption to meet this equality requirement. Given the tight historical correlation between GDP and energy consumption, the needed increase of GDP per capita in the developing world to the levels of the U.S. would deplete explored fossil fuel reserves in less than two decades. These estimates predict that the world economy would need to find a development model where growth would be achieved without heavy dependence on fossil fuels.« less

  18. Resource demand growth and sustainability due to increased world consumption

    SciTech Connect (OSTI)

    Balatsky, Alexander V.; Balatsky, Galina I.; Borysov, Stanislav S.

    2015-03-20

    The paper aims at continuing the discussion on sustainability and attempts to forecast the impossibility of the expanding consumption worldwide due to the planet’s limited resources. As the population of China, India and other developing countries continue to increase, they would also require more natural and financial resources to sustain their growth. We coarsely estimate the volumes of these resources (energy, food, freshwater) and the gross domestic product (GDP) that would need to be achieved to bring the population of India and China to the current levels of consumption in the United States. We also provide estimations for potentially needed immediate growth of the world resource consumption to meet this equality requirement. Given the tight historical correlation between GDP and energy consumption, the needed increase of GDP per capita in the developing world to the levels of the U.S. would deplete explored fossil fuel reserves in less than two decades. These estimates predict that the world economy would need to find a development model where growth would be achieved without heavy dependence on fossil fuels.

  19. GDP-L-fucose: {beta}-D-galactoside 2-{alpha}-Lfucosyltransferases, DNA sequences encoding the same, method for producing the same and a method of genotyping a person

    DOE Patents [OSTI]

    Lowe, J.B.; Lennon, G.; Rouquier, S.; Giorgi, D.; Kelly, R.J.

    1998-09-15

    The gene encoding GDP-L-fucose: {beta}-D-Galactoside 2-{alpha}-Lfucosyltransferase has been cloned, and a mutation in this gene has been found to be responsible for an individual being a non-secretor. 30 figs.

  20. GDP-L-fucose: .beta.-D-galactoside 2-.alpha.-L-fucosyltransferases, DNA sequences encoding the same, method for producing the same and a method of genotyping a person

    DOE Patents [OSTI]

    Lowe, John B.; Lennon, Gregory; Rouquier, Sylvie; Giorgi, Dominique; Kelly, Robert J.

    1998-01-01

    The gene encoding GDP-L-fucose: .beta.-D-Galactoside 2-.alpha.-L-fucosyltransferase has been cloned, and a mutation in this gene has been found to be responsible for an individual being a non-secretor.

  1. Rate Information

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  2. Corrosion fatigue crack growth in clad low-alloy steel. Part 2, Water flow rate effects in high sulfur plate steel

    SciTech Connect (OSTI)

    James, L.A; Lee, H.B.; Wire, G.L.; Novak, S.R.; Cullen, W.H.

    1996-04-01

    Corrosion fatigue crack propagation tests were conducted on a high- sulfur ASTM A302-B plate steel overlaid with weld-deposited Alloy EN82H cladding. The specimens featured semi-elliptical surface cracks penetrating approximately 6.3 mm of cladding into the underlying steel. The initial crack sizes were relatively large with surface lengths of 22.8--27.3 mm, and depths of 10.5--14.1 mm. The experiments were initiated in a quasi-stagnant low-oxygen (O{sub 2} < 10 ppb) aqueous environment at 243{degrees}C, under loading conditions ({Delta}K, R, cyclic frequency) conducive to environmentally-assisted cracking (EAC) under quasi-stagnant conditions. Following fatigue testing under quasi-stagnant conditions where EAC was observed, the specimens were then fatigue tested under conditions where active water flow of either 1.7 m/sec. or 4.7 m/sec. was applied parallel to the crack. Earlier experiments on unclad surface-cracked specimens of the same steel exhibited EAC under quasi- stagnant conditions, but water flow rates at 1.7 m/sec. and 5.0 m/sec. parallel to the crack mitigated EAC. In the present experiments on clad specimens, water flow at approximately the same as the lower of these velocities did not mitigate EAC, and a free stream velocity approximately the same as the higher of these velocities resulted in sluggish mitigation of EAC. The lack of robust EAC mitigation was attributed to the greater crack surface roughness in the cladding interfering with flow induced within the crack cavity. An analysis employing the computational fluid dynamics code, FIDAP, confirmed that frictional forces associated with the cladding crack surface roughness reduced the interaction between the free stream and the crack cavity.

  3. The R6A-1 peptide binds to switch II of G{alpha}{sub i1} but is not a GDP-dissociation inhibitor

    SciTech Connect (OSTI)

    Willard, Francis S. . E-mail: fwillard@med.unc.edu; Siderovski, David P.

    2006-01-27

    Heterotrimeric G-proteins are molecular switches that convert signals from membrane receptors into changes in intracellular physiology. Recently, several peptides that bind heterotrimeric G-protein {alpha} subunits have been isolated including the novel G{alpha}{sub i1} . GDP binding peptides R6A and KB-752. The R6A peptide and its minimized derivative R6A-1 interact with G{alpha}{sub i1} . GDP. Based on spectroscopic analysis of BODIPYFL-GTP{gamma}S binding to G{alpha}{sub i1}, it has been reported that R6A-1 has guanine nucleotide dissociation inhibitor (GDI) activity against G{alpha}{sub i1} [W.W. Ja, R.W. Roberts, Biochemistry 43 (28) (2004) 9265-9275]. Using radioligand binding, we show that R6A-1 is not a GDI for G{alpha}{sub i1} subunits. Furthermore, we demonstrate that R6A-1 reduces the fluorescence quantum yield of the G{alpha}{sub i1}-BODIPYFL-GTP{gamma}S complex, thus explaining the previously reported GDI activity as a fluorescence artifact. We further show that R6A-1 has significant sequence similarity to the guanine nucleotide exchange factor peptide KB-752 that binds to switch II of G{alpha}{sub i1}. We use competitive binding analysis to show that R6A-1 also binds to switch II of G{alpha} subunits.

  4. ARM - Lesson Plans: Rate of Coral Growth

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

    Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global Warming FAQ Just for Fun Meet our Friends Cool Sites Teachers Teachers' Toolbox ...

  5. PROCESS FOR CONTROLLING ANIMAL GROWTH RATE

    DOE Patents [OSTI]

    Visek, W.J.

    1962-04-10

    A method of injecting growing animals with the enzyme urease subcutaneously in increasing dosages is described; this generates within the blood anti-urease which enters the intestinal tract and inhibits the enzymatic decomposition of urea by urease in that location. Ammonia, one of the decomposition products, is thereby kept from diffusing through the intestinal walls into the blood, and this greatly reduces the energy requirements of the liver for removing the ammonia, thereby increasing the feeding efficiency of the animals. (AEC)

  6. China's Pathways to Achieving 40% ~ 45% Reduction in CO{sub 2} Emissions per Unit of GDP in 2020: Sectoral Outlook and Assessment of Savings Potential

    SciTech Connect (OSTI)

    Zheng, Nina; Fridley, David; Zhou, Nan; Levine, Mark; Price, Lynn; Ke, Jing

    2011-09-30

    Achieving China’s goal of reducing its carbon intensity (CO{sub 2} per unit of GDP) by 40% to 45% percent below 2005 levels by 2020 will require the strengthening and expansion of energy efficiency policies across the buildings, industries and transport sectors. This study uses a bottom-up, end-use model and two scenarios -- an enhanced energy efficiency (E3) scenario and an alternative maximum technically feasible energy efficiency improvement (Max Tech) scenario – to evaluate what policies and technical improvements are needed to achieve the 2020 carbon intensity reduction target. The findings from this study show that a determined approach by China can lead to the achievement of its 2020 goal. In particular, with full success in deepening its energy efficiency policies and programs but following the same general approach used during the 11th Five Year Plan, it is possible to achieve 49% reduction in CO{sub 2} emissions per unit of GDP (CO{sub 2} emissions intensity) in 2020 from 2005 levels (E3 case). Under the more optimistic but feasible assumptions of development and penetration of advanced energy efficiency technology (Max Tech case), China could achieve a 56% reduction in CO{sub 2} emissions intensity in 2020 relative to 2005 with cumulative reduction of energy use by 2700 Mtce and of CO{sub 2} emissions of 8107 Mt CO{sub 2} between 2010 and 2020. Energy savings and CO{sub 2} mitigation potential varies by sector but most of the energy savings potential is found in energy-intensive industry. At the same time, electricity savings and the associated emissions reduction are magnified by increasing renewable generation and improving coal generation efficiency, underscoring the dual importance of end-use efficiency improvements and power sector decarbonization.

  7. Rate Schedules

    Broader source: Energy.gov [DOE]

    One of the major responsibilities of Southeastern is to design, formulate, and justify rate schedules. Repayment studies prepared by the agency determine revenue requirements and appropriate rate...

  8. Finance & Rates

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

    all of its costs in the rates it charges customers for wholesale electricity and transmission services. The agency is committed to careful cost management consistent with its...

  9. Appendix B: High Economic Growth case projections

    Gasoline and Diesel Fuel Update (EIA)

    4 Appendix B Table B2. World gross domestic product (GDP) by region expressed in purchasing power parity, High Economic Growth case, 2011-40 (billion 2010 dollars) Region History Projections Average annual percent change, 2012-40 2011 2012 2020 2025 2030 2035 2040 OECD OECD Americas 18,616 19,080 24,230 28,258 32,427 36,956 42,539 2.9 United States a 15,021 15,369 19,590 22,852 26,146 29,678 34,146 2.9 Canada 1,396 1,422 1,717 1,921 2,143 2,398 2,680 2.3 Mexico and Chile 2,200 2,288 2,923 3,485

  10. ARM - Measurement - Hygroscopic growth

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

    govMeasurementsHygroscopic growth ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Hygroscopic growth The rate that aerosol particles grow at relative humidity values less than 100 percent. Sometimes supersaturation conditions are used in making this measurement. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the

  11. Rates Meetings and Workshops (pbl/rates)

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

    Rate Case Workshops Other Power Rates-Related Workshops July 1, 2004 - Rates and Finances Workshop (updated June 25, 2004) (financial and rate forecasts and scenarios for FY...

  12. Regional Dialogue Guidebook: Background on Products, Rates, and...

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

    Block Product 4. Renewable Energy Certificates (REC Program) Part 2: Tiered Rate Methodology (TRM) A. Tier 1 Rate Design B. Tier 2 Rate Alternatives 1. Load-Growth Service 2....

  13. Energy Intensity Trends in AEO2010 (released in AEO2010)

    Reports and Publications (EIA)

    2010-01-01

    Energy intensity (energy consumption per dollar of real GDP) indicates how much energy a country uses to produce its goods and services. From the early 1950s to the early 1970s, U.S. total primary energy consumption and real GDP increased at nearly the same annual rate. During that period, real oil prices remained virtually flat. In contrast, from the mid-1970s to 2008, the relationship between energy consumption and real GDP growth changed, with primary energy consumption growing at less than one-third the previous average rate and real GDP growth continuing to grow at its historical rate. The decoupling of real GDP growth from energy consumption growth led to a decline in energy intensity that averaged 2.8% per year from 1973 to 2008. In the Annual Energy Outlook 2010 Reference case, energy intensity continues to decline, at an average annual rate of 1.9% from 2008 to 2035.

  14. Assumption to the Annual Energy Outlook 2014 - International...

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    3.2. The GDP growth rate assumptions for non-U.S. countriesregions are taken from Oxford Economic Model (October, 2012). The values for growth in total liquids demand in the...

  15. Power Rates Announcements (pbl/rates)

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

    WP-10 Rate Case WP-07 Rate Case WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial Choices (2003-06) Power...

  16. Current BPA Power Rates (pbl/rates)

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

    and Workshops WP-10 Rate Case WP-07 Rate Case WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial...

  17. Table 2. Real Gross Domestic Product Growth Trends, Projected vs. Actual

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

    Real Gross Domestic Product Growth Trends, Projected vs. Actual Projected Real GDP Growth Trend (cumulative average percent growth in projected real GDP from first year shown for each AEO) 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 AEO 1994 3.09 3.15 2.86 2.78 2.73 2.65 2.62 2.60 2.56 2.53 2.52 2.49 2.45 2.41 2.40 2.36 2.32 2.29 AEO 1995 3.66 2.77 2.53 2.71 2.67 2.61 2.55 2.48 2.46 2.45 2.45 2.43 2.39 2.35 2.31 2.27 2.24 AEO 1996 2.61

  18. Current Power Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  19. Current Transmission Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  20. Previous Power Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  1. Previous Transmission Rates

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Current Power Rates Current Transmission Rates...

  2. Implications of Low Electricity Demand Growth

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

    2014 EIA Energy Conference July 14, 2014 | Washington, DC Jim Diefenderfer, Director, Office of Electricity, Coal, Nuclear, & Renewables Analysis U.S. Energy Information Administration Implications of low electricity demand growth Growth in electricity use slows, but still increases by 29% from 2012 to 2040 -2% 0% 2% 4% 6% 8% 10% 12% 14% 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 percent growth (3-year compounded annual growth rate) Source: EIA, Annual Energy Outlook 2014 Reference

  3. PNCA-02 Rate Case (rates/ratecases)

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

    Proposed Adjustment to the Rate for Interchange Energy Imbalances Under the Pacific Northwest Coordination Agreement (PNCA-02 Rate Case) (updated on April 26, 2002) BPA has issued...

  4. Incorporating a Time Horizon in Rate-of-Return Estimations: Discounted Cash Flow Model in Electric Transmission Rate Cases

    SciTech Connect (OSTI)

    Chatterjee, Bishu; Sharp, Peter A.

    2006-07-15

    Electric transmission and other rate cases use a form of the discounted cash flow model with a single long-term growth rate to estimate rates of return on equity. It cannot incorporate information about the appropriate time horizon for which analysts' estimates of earnings growth have predictive powers. Only a non-constant growth model can explicitly recognize the importance of the time horizon in an ROE calculation. (author)

  5. High Rate and Stable Cycling of Lithium Metal Anode (Journal...

    Office of Scientific and Technical Information (OSTI)

    Title: High Rate and Stable Cycling of Lithium Metal Anode Lithium (Li) metal is an ideal anode material for rechargeable batteries. However, dendritic Li growth and limited ...

  6. Rate Case Elements

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

    Proceeding Rate Information Residential Exchange Program Surplus Power Sales Reports Rate Case Elements BPA's rate cases are decided "on the record." That is, in making a decision...

  7. Power Rate Cases (pbl/rates)

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

    Choices (2003-06) Power Function Review (PFR) Firstgov Power Rate Cases BPA's wholesale power rates are set to recover its costs and repay the U.S. Treasury for the Federal...

  8. Chlorite Dissolution Rates

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

    Carroll, Susan

    Spreadsheets provides measured chlorite rate data from 100 to 300C at elevated CO2. Spreadsheet includes derived rate equation.

  9. Chlorite Dissolution Rates

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

    Carroll, Susan

    2013-07-01

    Spreadsheets provides measured chlorite rate data from 100 to 300C at elevated CO2. Spreadsheet includes derived rate equation.

  10. Particle growth in silane-hydrogen discharges

    SciTech Connect (OSTI)

    Kujundzic, Damir; Gallagher, Alan

    2006-02-01

    The growth of silicon particles has been measured in silane-hydrogen radio-frequency (rf) discharges using a typical hydrogen/silane dilution ratio (20) and the pressure range (1.2-2.2 Torr) used for the production of amorphous and microcrystalline silicon films and devices. By operating brief discharges without gas flow, the particle size is obtained from the afterglow diffusion and the particle density from the scattered-light intensity. These small-reactor data thus provide the expected particle size and density versus location-in a commercial large-area-isothermal-flowing-gas reactor. Particle growth rate is a strong function of pressure, whereas film growth rate is almost independent of pressure. Both growth rates are sensitive to rf voltage, although particle growth is more sensitive.

  11. Fatigue crack growth behavior of Ti-1100 at elevated temperature

    SciTech Connect (OSTI)

    Maxwell, D.C.; Nicholas, T.

    1995-12-31

    Effects of temperature, frequency, and cycles with superimposed hold times are evaluated in Ti-1100 in order to study the complex creep-fatigue-environment interactions in this material. Crack growth rate tests conducted at cyclic loading frequency of 1.0 Hz show that raising the temperature from 593 to 650 C has only a slightly detrimental effect on crack growth rate, although these temperatures produce growth rates significantly higher than at room temperature. From constant {Delta}K tests, the effects of temperature at constant frequency show a minimum crack growth rate at 250 C. From the minimum crack growth rate at 250 C, the crack growth rate increases linearly with temperature. Increases in frequency at constant temperatures of 593 and 650 C produce a continuous decrease in growth rate in going from 0.001 to 1.0 Hz, although the behavior is primarily cycle dependent in this region. Tests at 1.0 Hz with superimposed hold times from 1 to 1,000 s are used to evaluate creep-fatigue-environment interactions. Hold times at maximum load are found to initially decrease and then increase the cyclic crack growth rate with increasing duration. This is attributed to crack-tip blunting during short hold times and environmental degradation at long hold times. Hold times at minimum load show no change in growth rates, indicating that there is no net environmental degradation to the bulk material beyond that experienced during the baseline 1 Hz cycling.

  12. Before a Rate Case

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

    links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings and Workshops Customer...

  13. Rating Agency Reports

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

    Liabilities Financial Plan Financial Public Processes Asset Management Cost Verification Process Rate Cases Rate Information Residential Exchange Program Surplus Power Sales...

  14. 2012 Transmission Rate Schedules

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

    2014 Transmission, Ancillary, and Control Area Service Rate Schedules and General Rate Schedule Provisions (FY 2014-2015) October 2013 United States Department of Energy...

  15. BP-18 Rate Proceeding

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

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  16. BP-12 Rate Case

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

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  17. BP-16 Rate Case

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

    Skip navigation links Financial Information Financial Public Processes Asset Management Cost Verification Process Rate Cases BP-18 Rate Case Related Publications Meetings...

  18. Final Report - National Database of Utility Rates and Rate Structure...

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

    National Database of Utility Rates and Rate Structure Final Report - National Database of Utility Rates and Rate Structure Awardee: Illinois State University Location: Normal, IL ...

  19. The Panama Canal: It's all about connectivity

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

    Panama Canal: It's all about connectivity Panama at a glance GDP growth rate - last 10 years 7.5% GDP estimated- 2013 (dollars) 38,6b GDP per capita - 2013 estimated (in dollars) 13,032 Population (million) 3.5 Unemployment rate (in %) 4.0 Inflation rate - 2013 (in %) 4.08 It's all about Connectivity * 144 trade routes * 1,700 ports * 160 countries The Panama Canal's value added service The Panama Canal Service Package Reliability Sustainability Connectivity Economies of Scale * Opens 24 hours a

  20. Resonant thermonuclear reaction rate

    SciTech Connect (OSTI)

    Haubold, H.J.; Mathai, A.M.

    1986-08-01

    Basic physical principles for the resonant and nonresonant thermonuclear reaction rates are applied to find their standard representations for nuclear astrophysics. Closed-form representations for the resonant reaction rate are derived in terms of Meijer's G-italic-function. Analytic representations of the resonant and nonresonant nuclear reaction rates are compared and the appearance of Meijer's G-italic-function is discussed in physical terms.

  1. Improving Entrainment Rate Parameterization

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

    Entrainment Rate Parameterization For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Parameterization of entrainment rate is critical for improving representation of cloud- and convection-related processes in climate models; however, much remains unclear. This work seeks to improve understanding and parameterization of entrainment rate by use of aircraft observations and large-eddy simulations of shallow cumulus clouds over

  2. Draft Tiered Rate Methodology

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

    For Regional Dialogue Discussion Purposes Only Pre-Decisional Draft Tiered Rates Methodology March 7, 2008 Pre-decisional, Deliberative, For Discussion Purposes Only March 7,...

  3. LCC Guidance Rates

    Broader source: Energy.gov [DOE]

    Notepad text file provides the LCC guidance rates in a numbered format for the various regions throughout the U.S.

  4. Quartz crystal growth

    DOE Patents [OSTI]

    Baughman, Richard J.

    1992-01-01

    A process for growing single crystals from an amorphous substance that can undergo phase transformation to the crystalline state in an appropriate solvent. The process is carried out in an autoclave having a lower dissolution zone and an upper crystallization zone between which a temperature differential (.DELTA.T) is maintained at all times. The apparatus loaded with the substance, solvent, and seed crystals is heated slowly maintaining a very low .DELTA.T between the warmer lower zone and cooler upper zone until the amorphous substance is transformed to the crystalline state in the lower zone. The heating rate is then increased to maintain a large .DELTA.T sufficient to increase material transport between the zones and rapid crystallization. .alpha.-Quartz single crystal can thus be made from fused quartz in caustic solvent by heating to 350.degree. C. stepwise with a .DELTA.T of 0.25.degree.-3.degree. C., increasing the .DELTA.T to about 50.degree. C. after the fused quartz has crystallized, and maintaining these conditions until crystal growth in the upper zone is completed.

  5. Evaluation of the St. Lucia geothermal resource: macroeconomic models

    SciTech Connect (OSTI)

    Burris, A.E.; Trocki, L.K.; Yeamans, M.K.; Kolstad, C.D.

    1984-08-01

    A macroeconometric model describing the St. Lucian economy was developed using 1970 to 1982 economic data. Results of macroeconometric forecasts for the period 1983 through 1985 show an increase in gross domestic product (GDP) for 1983 and 1984 with a decline in 1985. The rate of population growth is expected to exceed GDP growth so that a small decline in per capita GDP will occur. We forecast that garment exports will increase, providing needed employment and foreign exchange. To obtain a longer-term but more general outlook on St. Lucia's economy, and to evaluate the benefit of geothermal energy development, we applied a nonlinear programming model. The model maximizes discounted cumulative consumption.

  6. Growth in Solar Means Growth in Ohio | Department of Energy

    Energy Savers [EERE]

    Growth in Solar Means Growth in Ohio Growth in Solar Means Growth in Ohio October 6, 2010 - 2:26pm Addthis Lorelei Laird Writer, Energy Empowers Editor's Note: Yesterday Secretary ...

  7. Best Practices: Escalation Rates

    Office of Environmental Management (EM)

    Best Practices Escalation Rates Hosted by: FEDERAL UTILITY PARTNERSHIP WORKING GROUP SEMINAR November 3-4, 2015 Houston, TX Federal Utility Partnership Working Group November 3-4, 2015 Houston, TX Federal Utility Partnership Working Group November 3-4, 2015 Houston, TX Best Practices: Escalation Rate Value of future energy savings * Provides purchasing power for implementing a robust, comprehensive and customized ECM set * Provides an option for paying back financing in the shortest possible

  8. 2007-2009 Power Rate Adjustments (pbl/rates)

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

    Function Review (PFR) Firstgov FY 2007 2009 Power Rate Adjustments BPA's 2007-2009 Wholesale Power Rate Schedules and General Rate Schedule Provisions (GRSPs) took effect on...

  9. WP-07 Power Rate Case (rates/ratecases)

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

    Meetings & Workshops Rate Case Parties Web Site WP-07 Supplemental Rate Case ASC Methodology Adjustments (2007-2009) Adjustments (2002-2006) Previous Rate Cases Financial...

  10. Solidification at the High and Low Rate Extreme

    SciTech Connect (OSTI)

    Halim Meco

    2004-12-19

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

  11. UV absorption control of thin film growth

    DOE Patents [OSTI]

    Biefeld, Robert M.; Hebner, Gregory A.; Killeen, Kevin P.; Zuhoski, Steven P.

    1991-01-01

    A system for monitoring and controlling the rate of growth of thin films in an atmosphere of reactant gases measures the UV absorbance of the atmosphere and calculates the partial pressure of the gases. The flow of reactant gases is controlled in response to the partial pressure.

  12. Faster plant growth in a safe, economical way

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

    Faster plant growth in a safe, economical way Faster plant growth in a safe, economical way When applied to plants, Take-Off(tm) speeds crop emergence, increases growth rates and yields, improves stress tolerance and nutrient value, and reduces need for nitrogen fertilizers. April 3, 2012 Farmer in wheat field inspecting wheat Biagro Western offers Take-Off(tm), a metabolic plant stimulant that will allow farmers to increase crop carbon fixation and thereby increase nitrate uptake and nitrogen

  13. Sequoia Messaging Rate Benchmark

    Energy Science and Technology Software Center (OSTI)

    2008-01-22

    The purpose of this benchmark is to measure the maximal message rate of a single compute node. The first num_cores ranks are expected to reside on the 'core' compute node for which message rate is being tested. After that, the next num_nbors ranks are neighbors for the first core rank, the next set of num_nbors ranks are neighbors for the second core rank, and so on. For example, testing an 8-core node (num_cores = 8)more » with 4 neighbors (num_nbors = 4) requires 8 + 8 * 4 - 40 ranks. The first 8 of those 40 ranks are expected to be on the 'core' node being benchmarked, while the rest of the ranks are on separate nodes.« less

  14. Residential Solar Valuation Rates

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

    Solar Valuation Rates Karl R. Rábago Rábago Energy LLC 1 The Ideal Residential Solar Tariff ‣ Fair to the utility and non-solar customers ‣ Fair compensation to the solar customer ‣ Decouple compensation from incentives ‣ Align public policy goals (decouple compensation from consumption) ‣ Intuitively sound and administratively simple 2 Historical Antecedents ‣ Externalities ‣ Price ≠ Cost ‣ Green Power ‣ Small Is Profitable (http://www.smallisprofitable.org/) ‣ Local

  15. Rotational rate sensor

    DOE Patents [OSTI]

    Hunter, Steven L. (Livermore, CA)

    2002-01-01

    A rate sensor for angular/rotational acceleration includes a housing defining a fluid cavity essentially completely filled with an electrolyte fluid. Within the housing, such as a toroid, ions in the fluid are swept during movement from an excitation electrode toward one of two output electrodes to provide a signal for directional rotation. One or more ground electrodes within the housing serve to neutralize ions, thus preventing any effect at the other output electrode.

  16. Renewable Energy Growth Program

    Office of Energy Efficiency and Renewable Energy (EERE)

    In 2014, Act H 7727 created the Renewable Energy Growth (REG) program with the goal to promote installation of grid connected renewable energy within the load zones of electric distribution...

  17. Writing Effective Initial Summary Ratings Initial Summary Rating...

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

    Initial Summary Ratings Initial Summary Rating (ISR) At the end of the performance cycle, the rating official must prepare an ISR in ePerformance for each SES member who has ...

  18. Smart Cities - Smart Growth

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

    Smart Cities - Smart Growth The United States Secretaries of Commerce will co-lead a Business Development Mission to China from April 12-17, 2015. This mission will promote U.S. clean technology products and services in the areas of green building/construction, energy efficiency, carbon capture, utilization and storage (CCUS) and environmental technologies in support of the Smart Cities-Smart Growth theme. On November 12, President Obama and President Xi jointly announced the two countries'

  19. FGF growth factor analogs

    DOE Patents [OSTI]

    Zamora, Paul O.; Pena, Louis A.; Lin, Xinhua; Takahashi, Kazuyuki

    2012-07-24

    The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

  20. Writing Effective Initial Summary Ratings Initial Summary Rating (ISR)

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

    Initial Summary Ratings Initial Summary Rating (ISR) At the end of the performance cycle, the rating official must prepare an ISR in ePerformance for each SES member who has completed at least 90 days on an established performance plan. Rating officials must take into account the SES member's accomplishments achieved during the performance cycle and the impact to the organization's performance. Rating officials must appraise executives realistically and fairly and avoid ratings inflation.

  1. October 1996 - September 2001 Wholesale Power Rates (rates/previous...

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

    affecting a specific power purchase. For more specific information see: 1996 Final Wholesale Power and Transmission Rate Schedules: Power Rates (PDF, 84 pages, 188 kb) Ancillary...

  2. PULSE RATE DIVIDER

    DOE Patents [OSTI]

    McDonald, H.C. Jr.

    1962-12-18

    A compact pulse-rate divider circuit affording low impedance output and high input pulse repetition rates is described. The circuit features a single secondary emission tube having a capacitor interposed between its dynode and its control grid. An output pulse is produced at the anode of the tube each time an incoming pulse at the control grid drives the tube above cutoff and the duration of each output pulse corresponds to the charging time of the capacitor. Pulses incoming during the time the grid bias established by the discharging capacitor is sufficiently negative that the pulses are unable to drive the tube above cutoff do not produce output pulses at the anode; these pulses are lost and a dividing action is thus produced by the circuit. The time constant of the discharge path may be vanied to vary in turn the division ratio of the circuit; the time constant of the charging circuit may be varied to vary the width of the output pulses. (AEC)

  3. Conditioning biomass for microbial growth

    DOE Patents [OSTI]

    Bodie, Elizabeth A; England, George

    2015-03-31

    The present invention relates to methods for improving the yield of microbial processes that use lignocellulose biomass as a nutrient source. The methods comprise conditioning a composition comprising lignocellulose biomass with an enzyme composition that comprises a phenol oxidizing enzyme. The conditioned composition can support a higher rate of growth of microorganisms in a process. In one embodiment, a laccase composition is used to condition lignocellulose biomass derived from non-woody plants, such as corn and sugar cane. The invention also encompasses methods for culturing microorganisms that are sensitive to inhibitory compounds in lignocellulose biomass. The invention further provides methods of making a product by culturing the production microorganisms in conditioned lignocellulose biomass.

  4. Piggyback Tectonics- Long-Term Growth Of Kilauea On The South...

    Open Energy Info (EERE)

    (15-40,000 km3); lava-thickness accumulation rates appear to have remained nearly constant during edifice growth, as effusion rates increased from 25 106 m3yr at end of...

  5. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier5Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier5Rate Jump to: navigation, search This is a property of type...

  6. Property:OpenEI/UtilityRate/DemandRateStructure/Tier1Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateDemandRateStructureTier1Rate Jump to: navigation, search This is a property of type...

  7. Property:OpenEI/UtilityRate/DemandRateStructure/Tier3Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateDemandRateStructureTier3Rate Jump to: navigation, search This is a property of type...

  8. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier3Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier3Rate Jump to: navigation, search This is a property of type...

  9. Property:OpenEI/UtilityRate/EnergyRateStructure/Tier4Rate | Open...

    Open Energy Info (EERE)

    Property Edit with form History Facebook icon Twitter icon Property:OpenEIUtilityRateEnergyRateStructureTier4Rate Jump to: navigation, search This is a property of type...

  10. 1979 revenue growth belies utility industry problems

    SciTech Connect (OSTI)

    Lincicome, R.

    1980-06-01

    Despite growth in revenues during 1979, electric utilities are greatly troubled by high inflation, restricted capital, and the lack of rate relief from utility commissions. The growth, although smaller than normal, will likely convince commissions to respond to rate increase requests by authorizing only the smallest possible increases. With inflationary pressures eroding utility companies' financial base, the benefits of rate increases are wiped out after a year or so, necessitating a return to the commissions for futher adjustments. This up-down cycling is reflected in the report of the performances of the top one hundred utility companies. Earning growth statistics, sales data, financial statistics, and company performances (electric sales, customers served, revenues, and after-tax net income) of top one hundred electric utilities are given in separate tables for 1979. Overall, kWh sales were up 2.9%; revenues were up 13.4%; net income was up 8.1%; and overall earnings performance was a weak increase of 9.4%. (SAC)

  11. Plant growth promoting rhizobacterium

    SciTech Connect (OSTI)

    Doktycz, Mitchel John; Pelletier, Dale A.; Schadt, Christopher Warren; Tuskan, Gerald A.; Weston, David

    2015-08-11

    The present invention is directed to the Pseudomonas fluorescens strain GM30 deposited under ATCC Accession No. PTA-13340, compositions containing the GM30 strain, and methods of using the GM30 strain to enhance plant growth and/or enhance plant resistance to pathogens.

  12. WP-02 Power Rate Case (rates/ratecases)

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

    WP-02 Power Rate Case (Updated on May 7, 2004) In May of 2000, the BPA Administrator signed a Record of Decision (ROD) on the 2002 Final Power Rate Proposal for the October 2001...

  13. 2007-2009 Power Rates Quarterly Updates (pbl/rates)

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

    (PFR) Firstgov FY 2007 2009 Power Rates Quarterly Updates In BPAs 2007-2009 Wholesale Power Rate Case (WP-07), BPA agreed that it would post reports about BPAs power...

  14. October 2005 - March 2006 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 30.56% non-Slice LB + FB + SN CRAC adjustment for each month of the six-month rate period. The table below...

  15. April - September 2002 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 40.77% non-Slice LB CRAC adjustment for each month of the six-month rate period. The table below is simply a...

  16. October 2004 - March 2005 Power Rates (rates/previous)

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

    The PDF documents above provide tables of monthly Slice, PF, RL, and IP rates with the LB + FB + SN CRAC adjustments for each month of the rate period. The table below is simply...

  17. April - September 2005 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 36.93% non-Slice LB + FB + SN CRAC adjustment for each month of the six-month rate period. The table below...

  18. October 2003 - March 2004 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 43.66% non-Slice LB + FB + SN CRAC adjustment for each month of the rate period. The table below is simply a...

  19. October 2002 - March 2003 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 43.91% non-Slice LB + FB CRAC adjustment for each month of the six-month rate period. The table below is...

  20. October 2001 - March 2002 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 46% non-Slice LB CRAC adjustment for each month of the six-month rate period. The table below is simply a...

  1. April - September 2003 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 49.50% non-Slice LB + FB CRAC adjustment for each month of the six-month rate period. The table below is...

  2. April - September 2004 Power Rates (rates/previous)

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

    above provides a table of monthly Slice, PF, RL, and IP rates with a 47.00% non-Slice LB + FB + SN CRAC adjustment for each month of the six-month rate period. The table below...

  3. FPS-96R Rate Adjustment (rates/ratecases)

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

    Final Firm Power Products and Services (FPS-96R) Rate Adjustment In August 1999, BPA proposed to correct errors in the Firm Power Products and Services rate schedule (FPS-96), and...

  4. National Utility Rate Database: Preprint

    SciTech Connect (OSTI)

    Ong, S.; McKeel, R.

    2012-08-01

    When modeling solar energy technologies and other distributed energy systems, using high-quality expansive electricity rates is essential. The National Renewable Energy Laboratory (NREL) developed a utility rate platform for entering, storing, updating, and accessing a large collection of utility rates from around the United States. This utility rate platform lives on the Open Energy Information (OpenEI) website, OpenEI.org, allowing the data to be programmatically accessed from a web browser, using an application programming interface (API). The semantic-based utility rate platform currently has record of 1,885 utility rates and covers over 85% of the electricity consumption in the United States.

  5. Project Definition Rating Index Workbook

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Project Definition Rating Index (PDRI) Workbook is a tool that was developed to support DOE G-413.3-12A, U. S. Department of Energy Project Definition Rating Index Guide for Traditional Nuclear...

  6. Electrochemical Solution Growth: Gallium Nitride Crystal Growth - Energy

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

    Innovation Portal Vehicles and Fuels Vehicles and Fuels Building Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Electrochemical Solution Growth: Gallium Nitride Crystal Growth Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (886 KB) Technology Marketing SummarySandia National Laboratories has developed a disruptive new crystal growth technology, called Electrochemical Solution Growth (ESG).

  7. Growth of age-0 steelhead (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis) in the Pine River watershed, Alcona County, Michigan

    SciTech Connect (OSTI)

    Bellgraph, Brian J.; Thompson, Bradley E.; Hayes, Daniel B.; Riley, Timothy S.

    2006-12-01

    We sampled ten sites within the Pine River watershed, Alcona County, Michigan. In 2001, age-0 steelhead (Oncorhynchus mykiss) were collected to determine growth rates. In 2002, emergence dates of steelhead were determined by observational studies and age-0 steelhead and brook trout (Salvelinus fontinalis) were collected to determine growth rates. Steelhead emergence occurred from late June to mid-July 2002. Growth rates of both species varied among branches within the watershed (P<0.05). Steelhead growth varied from 0.24 to 0.42 mm/day and brook trout growth varied from 0.22 to 0.37 mm/day.

  8. Economics of Future Growth in Photovoltaics Manufacturing

    SciTech Connect (OSTI)

    Basore, Paul A.; Chung, Donald; Buonassisi, Tonio

    2015-06-14

    The past decade's record of growth in the photovoltaics manufacturing industry indicates that global investment in manufacturing capacity for photovoltaic modules tends to increase in proportion to the size of the industry. The slope of this proportionality determines how fast the industry will grow in the future. Two key parameters determine this slope. One is the annual global investment in manufacturing capacity normalized to the manufacturing capacity for the previous year (capacity-normalized capital investment rate, CapIR, units $/W). The other is how much capital investment is required for each watt of annual manufacturing capacity, normalized to the service life of the assets (capacity-normalized capital demand rate, CapDR, units $/W). If these two parameters remain unchanged from the values they have held for the past few years, global manufacturing capacity will peak in the next few years and then decline. However, it only takes a small improvement in CapIR to ensure future growth in photovoltaics. Any accompanying improvement in CapDR will accelerate that growth.

  9. Validating hydrodynamic growth in National Ignition Facility implosions

    SciTech Connect (OSTI)

    Peterson, J. L. Casey, D. T.; Hurricane, O. A.; Raman, K. S.; Robey, H. F.; Smalyuk, V. A.

    2015-05-15

    We present new hydrodynamic growth experiments at the National Ignition Facility, which extend previous measurements up to Legendre mode 160 and convergence ratio 4, continuing the growth factor dispersion curve comparison of the low foot and high foot pulses reported by Casey et al. [Phys. Rev. E 90, 011102(R) (2014)]. We show that the high foot pulse has lower growth factor and lower growth rate than the low foot pulse. Using novel on-capsule fiducial markers, we observe that mode 160 inverts sign (changes phase) for the high foot pulse, evidence of amplitude oscillations during the Richtmyer-Meshkov phase of a spherically convergent system. Post-shot simulations are consistent with the experimental measurements for all but the shortest wavelength perturbations, reinforcing the validity of radiation hydrodynamic simulations of ablation front growth in inertial confinement fusion capsules.

  10. Shallow melt apparatus for semicontinuous czochralski crystal growth

    DOE Patents [OSTI]

    Wang, Tihu; Ciszek, Theodore F.

    2006-01-10

    In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

  11. SN-03 Rate Case Workshops (rates/meetings)

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

    Materials Related Link: SN-03 Power Rate Case May 1 & 13, 2003 - Debt and Liquidity Strategies workshops (on BPA Corporate web site) March 27, 2003 - SN CRAC Prescheduling...

  12. What Is the Right Rate? Loan Rates and Demand

    Broader source: Energy.gov [DOE]

    Better Buildings Neighborhood Program Financing Peer Exchange Call: “What is the Right Rate?” call slides and discussion summary, December 1, 2011.

  13. Kinetics of monolayer graphene growth by segregation on Pd(111)

    SciTech Connect (OSTI)

    Mok, H. S.; Murata, Y.; Kodambaka, S., E-mail: kodambaka@ucla.edu [Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California 90095 (United States); Ebnonnasir, A.; Ciobanu, C. V. [Department of Mechanical Engineering and Materials Science Program, Colorado School of Mines, Golden, Colorado 80401 (United States); Nie, S.; McCarty, K. F. [Sandia National Laboratories, Livermore, California 94550 (United States)

    2014-03-10

    Using in situ low-energy electron microscopy and density functional theory calculations, we follow the growth of monolayer graphene on Pd(111) via surface segregation of bulk-dissolved carbon. Upon lowering the substrate temperature, nucleation of graphene begins on graphene-free Pd surface and continues to occur during graphene growth. Measurements of graphene growth rates and Pd surface work functions establish that this continued nucleation is due to increasing C adatom concentration on the Pd surface with time. We attribute this anomalous phenomenon to a large barrier for attachment of C adatoms to graphene coupled with a strong binding of the non-graphitic C to the Pd surface.

  14. Microsoft Word - Highlights.doc

    Gasoline and Diesel Fuel Update (EIA)

    September 2010 1 September 2010 Short-Term Energy Outlook September 8, 2010 Release Highlights  These projections reflect updated expectations for economic activity, with forecasted U.S. real gross domestic product (GDP) growth of 2.8 percent in 2010 and 2.3 percent in 2011, down from the previous Outlook's growth projections of 3.1 and 2.7 percent for 2010 and 2011, respectively. The 2011 world oil-consumption-weighted real GDP growth rate is also lowered, to 3.3 percent from the 3.6 percent

  15. Controlling single and few-layer graphene crystals growth in a solid carbon source based chemical vapor deposition

    SciTech Connect (OSTI)

    Papon, Remi; Sharma, Subash; Shinde, Sachin M.; Vishwakarma, Riteshkumar; Tanemura, Masaki [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Kalita, Golap, E-mail: kalita.golap@nitech.ac.jp [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Center for Fostering Young and Innovative Researchers, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555 (Japan)

    2014-09-29

    Here, we reveal the growth process of single and few-layer graphene crystals in the solid carbon source based chemical vapor deposition (CVD) technique. Nucleation and growth of graphene crystals on a polycrystalline Cu foil are significantly affected by the injection of carbon atoms with pyrolysis rate of the carbon source. We observe micron length ribbons like growth front as well as saturated growth edges of graphene crystals depending on growth conditions. Controlling the pyrolysis rate of carbon source, monolayer and few-layer crystals and corresponding continuous films are obtained. In a controlled process, we observed growth of large monolayer graphene crystals, which interconnect and merge together to form a continuous film. On the other hand, adlayer growth is observed with an increased pyrolysis rate, resulting few-layer graphene crystal structure and merged continuous film. The understanding of monolayer and few-layer crystals growth in the developed CVD process can be significant to grow graphene with controlled layer numbers.

  16. Material and methods to increase plant growth and yield

    SciTech Connect (OSTI)

    Kirst, Matias

    2015-09-15

    The present invention relates to materials and methods for modulating growth rates, yield, and/or resistance to drought conditions in plants. In one embodiment, a method of the invention comprises increasing expression of an hc1 gene (or a homolog thereof that provides for substantially the same activity), or increasing expression or activity of the protein encoded by an hc1 gene thereof, in a plant, wherein expression of the hc1 gene or expression or activity of the protein encoded by an hc1 gene results in increased growth rate, yield, and/or drought resistance in the plant.

  17. ARM - Measurement - Radiative heating rate

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

    govMeasurementsRadiative heating rate ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Radiative heating rate The heating rate due to the divergence of long and shortwave radiative flux. Categories Radiometric, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a

  18. FACET Emittance Growth

    SciTech Connect (OSTI)

    Frederico, J; Hogan, M.J.; Nosochkov, Y.; Litos, M.D.; Raubenheimer, T.; /SLAC

    2011-04-05

    FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration. The FACET beamline consists of a chicane and final focus system to compress the 23 GeV, 3.2 nC electron bunches to {approx}20 {micro}m long and {approx}10 {micro}m wide. Simulations of the FACET beamline indicate the short-duration and large, 1.5% rms energy spread beams may suffer a factor of four emittance growth from a combination of chromaticity, incoherent synchrotron radiation (ISR), and coherent synchrotron radiation (CSR). Emittance growth is directly correlated to head erosion in plasma wakefield acceleration and is a limiting factor in single stage performance. Studies of the geometric, CSR, and ISR components are presented. Numerical calculation of the rms emittance can be overwhelmed by long tails in the simulated phase space distributions; more useful definitions of emittance are given. A complete simulation of the beamline is presented as well, which agrees with design specifications.

  19. Wholesale Power Rate Schedules | Department of Energy

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

    Rate Schedules Wholesale Power Rate Schedules Wholesale Power Rate Schedules October 1, 2012 ALA-1-N Wholesale Power Rate Schedule Area: PowerSouth Energy Cooperative System:...

  20. Sustainable Building Rating Systems Summary

    SciTech Connect (OSTI)

    Fowler, Kimberly M.; Rauch, Emily M.

    2006-07-01

    The purpose of this document is to offer information that could be used to compare and contrast sustainable building rating systems.

  1. Rate Schedules | Department of Energy

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

    Repayment studies prepared by the agency determine revenue requirements and appropriate rate levels and these studies for each of Southeastern's four power marketing systems are ...

  2. Global Green Growth Institute | Open Energy Information

    Open Energy Info (EERE)

    Growth Institute Redirect page Jump to: navigation, search REDIRECT Green Growth Strategy Support Retrieved from "http:en.openei.orgwindex.php?titleGlobalGreenGrowthIn...

  3. Role of hydrogen in evolution of plasma parameters and dust growth in capacitively coupled dusty plasmas

    SciTech Connect (OSTI)

    Chai, K. B.; Choe, Wonho; Seon, C. R.; Chung, C. W.

    2010-11-15

    The temporal behavior of naturally produced dust parameters (radius and density) and plasma parameters (electron temperature and ion flux) was investigated in radio frequency SiH{sub 4}/H{sub 2}/Ar plasmas. As a result, the electron temperature and ion flux were shown to be strongly correlated with the three-step dust growth pattern. In addition, the generation of dust particles was suppressed by mixing more hydrogen gas due to the plasma chemistry, and consequently, the dust growth rate in the molecular accretion growth, which is known to be proportional to the growth rate of thin film deposition, increased.

  4. Method for accurate growth of vertical-cavity surface-emitting lasers

    DOE Patents [OSTI]

    Chalmers, S.A.; Killeen, K.P.; Lear, K.L.

    1995-03-14

    The authors report a method for accurate growth of vertical-cavity surface-emitting lasers (VCSELs). The method uses a single reflectivity spectrum measurement to determine the structure of the partially completed VCSEL at a critical point of growth. This information, along with the extracted growth rates, allows imprecisions in growth parameters to be compensated for during growth of the remaining structure, which can then be completed with very accurate critical dimensions. Using this method, they can now routinely grow lasing VCSELs with Fabry-Perot cavity resonance wavelengths controlled to within 0.5%. 4 figs.

  5. Method for accurate growth of vertical-cavity surface-emitting lasers

    DOE Patents [OSTI]

    Chalmers, Scott A.; Killeen, Kevin P.; Lear, Kevin L.

    1995-01-01

    We report a method for accurate growth of vertical-cavity surface-emitting lasers (VCSELs). The method uses a single reflectivity spectrum measurement to determine the structure of the partially completed VCSEL at a critical point of growth. This information, along with the extracted growth rates, allows imprecisions in growth parameters to be compensated for during growth of the remaining structure, which can then be completed with very accurate critical dimensions. Using this method, we can now routinely grow lasing VCSELs with Fabry-Perot cavity resonance wavelengths controlled to within 0.5%.

  6. Method for enhancing microbial utilization rates of gases using perfluorocarbons

    DOE Patents [OSTI]

    Turick, C.E.

    1997-06-10

    A method of enhancing the bacterial reduction of industrial gases using perfluorocarbons (PFCs) is disclosed. Because perfluorocarbons (PFCs) allow for a much greater solubility of gases than water does, PFCs have the potential to deliver gases in higher concentrations to microorganisms when used as an additive to microbial growth media thereby increasing the rate of the industrial gas conversion to economically viable chemicals and gases. 3 figs.

  7. Method for enhancing microbial utilization rates of gases using perfluorocarbons

    DOE Patents [OSTI]

    Turick, Charles E. (Idaho Falls, ID)

    1997-01-01

    A method of enhancing the bacterial reduction of industrial gases using perfluorocarbons (PFCs) is disclosed. Because perfluorocarbons (PFCs) allow for a much greater solubility of gases than water does, PFCs have the potential to deliver gases in higher concentrations to microorganisms when used as an additive to microbial growth media thereby increasing the rate of the industrial gas conversion to economically viable chemicals and gases.

  8. BPA revises oversupply rate proposal

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

    comments until May 22, 2013. The rate-setting process will end with the administrator making a decision based on the record developed in the case. BPA expects to issue a final...

  9. Tier 2 Vintage Rate Workshop

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

    at a Tier 2 rate 3) Combination of the two On Nov 1, 2009, customers made their elections for how they will serve their Above-RHWM Load during the FY 2012-2014 purchase...

  10. DOE Guidance-Category Rating

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

    August 27, 2010 MEMORANDUM FOR HUMAN RESOURCES DIRECTORS FROM: SARA"iJ. Boku1, DIRECToR OF HUMAN CTAL MANAGEMENT SUBJECT: GUIDANCE MEMORANDUM 10 CATEGORY RATING The purpose of ...

  11. Shallow Melt Apparatus for Semicontinuous Czochralski Crystal Growth

    DOE Patents [OSTI]

    Wang, T.; Ciszek, T. F.

    2006-01-10

    In a single crystal pulling apparatus for providing a Czochralski crystal growth process, the improvement of a shallow melt crucible (20) to eliminate the necessity supplying a large quantity of feed stock materials that had to be preloaded in a deep crucible to grow a large ingot, comprising a gas tight container a crucible with a deepened periphery (25) to prevent snapping of a shallow melt and reduce turbulent melt convection; source supply means for adding source material to the semiconductor melt; a double barrier (23) to minimize heat transfer between the deepened periphery (25) and the shallow melt in the growth compartment; offset holes (24) in the double barrier (23) to increase melt travel length between the deepened periphery (25) and the shallow growth compartment; and the interface heater/heat sink (22) to control the interface shape and crystal growth rate.

  12. Motor vehicle output and GDP, 1968-2007.

    SciTech Connect (OSTI)

    Santini, D. J.; Poyer, D. A.

    2008-01-01

    In this paper, we assess the performance of the BEA series 'value of motor vehicle output' as an indicator of the business cycle over the period 1968-2007. We statistically assess the causal relationship between real motor vehicle output (RMVO) and real gross domestic product (RGDP). This is accomplished by standard estimation and statistical methods used to assess vector autoregressive models. This assessment represents the initial results of a more encompassing research project, the intent of which is to determine the dynamic interaction of the transport sector with the overall economy. It's a start to a more comprehensive assessment of how transport and economic activity interrelate.

  13. Precision growth index using the clustering of cosmic structures and growth data

    SciTech Connect (OSTI)

    Pouri, Athina; Basilakos, Spyros; Plionis, Manolis E-mail: svasil@academyofathens.gr

    2014-08-01

    We use the clustering properties of Luminous Red Galaxies (LRGs) and the growth rate data provided by the various galaxy surveys in order to constrain the growth index ?) of the linear matter fluctuations. We perform a standard ?{sup 2}-minimization procedure between theoretical expectations and data, followed by a joint likelihood analysis and we find a value of ?=0.560.05, perfectly consistent with the expectations of the ?CDM model, and ?{sub m0}=0.290.01, in very good agreement with the latest Planck results. Our analysis provides significantly more stringent growth index constraints with respect to previous studies, as indicated by the fact that the corresponding uncertainty is only ?0.09?. Finally, allowing ? to vary with redshift in two manners (Taylor expansion around z=0, and Taylor expansion around the scale factor), we find that the combined statistical analysis between our clustering and literature growth data alleviates the degeneracy and obtain more stringent constraints with respect to other recent studies.

  14. Final Report- National Database of Utility Rates and Rate Structure

    Broader source: Energy.gov [DOE]

    One of the key informational barriers for consumers, installers, regulators and policymakers, is the proper comparison cost of utility-supplied electricity that will be replaced with a Photovoltaic (PV) system. Oftentimes, these comparisons are made with national or statewide averages which results in inaccurate comparisons and conclusions. Illinois State University seeks to meet the need for accurate information about electricity costs and rate structure by building a national database of utility rates and rate structures. The database will build upon the excellent framework that was developed by the OpenEI.org initiative and extend it in several important ways. First, the data will be populated and monitored by a team of trained regulatory economists. Second, the database will be more comprehensive because it will be populated with data from newer competitive retail suppliers for states that have restructured their electricity markets to allow such suppliers. Third, the University and its Institute for Regulatory Policy Studies will maintain the database and ensure that it contains the most recent rate information.

  15. BPA Power Rates (pbl/main)

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

    rates, please see the transmission rates web site. Inactive Rate Cases Integrated Business Review (IBR) Integrated Program Review (IPR) Quarterly Business Review (QBR) Content...

  16. Coal Transportation Rate Sensitivity Analysis

    Reports and Publications (EIA)

    2005-01-01

    On December 21, 2004, the Surface Transportation Board (STB) requested that the Energy Information Administration (EIA) analyze the impact of changes in coal transportation rates on projected levels of electric power sector energy use and emissions. Specifically, the STB requested an analysis of changes in national and regional coal consumption and emissions resulting from adjustments in railroad transportation rates for Wyoming's Powder River Basin (PRB) coal using the National Energy Modeling System (NEMS). However, because NEMS operates at a relatively aggregate regional level and does not represent the costs of transporting coal over specific rail lines, this analysis reports on the impacts of interregional changes in transportation rates from those used in the Annual Energy Outlook 2005 (AEO2005) reference case.

  17. LINEAR COUNT-RATE METER

    DOE Patents [OSTI]

    Henry, J.J.

    1961-09-01

    A linear count-rate meter is designed to provide a highly linear output while receiving counting rates from one cycle per second to 100,000 cycles per second. Input pulses enter a linear discriminator and then are fed to a trigger circuit which produces positive pulses of uniform width and amplitude. The trigger circuit is connected to a one-shot multivibrator. The multivibrator output pulses have a selected width. Feedback means are provided for preventing transistor saturation in the multivibrator which improves the rise and decay times of the output pulses. The multivibrator is connected to a diode-switched, constant current metering circuit. A selected constant current is switched to an averaging circuit for each pulse received, and for a time determined by the received pulse width. The average output meter current is proportional to the product of the counting rate, the constant current, and the multivibrator output pulse width.

  18. High Rate and Stable Cycling of Lithium Metal Anode

    SciTech Connect (OSTI)

    Qian, Jiangfeng; Henderson, Wesley A.; Xu, Wu; Bhattacharya, Priyanka; Engelhard, Mark H.; Borodin, Oleg; Zhang, Jiguang

    2015-02-20

    Lithium (Li) metal is an ideal anode material for rechargeable batteries. However, dendritic Li growth and limited Coulombic efficiency (CE) during repeated Li deposition/stripping processes have prevented the application of this anode in rechargeable Li metal batteries, especially for use at high current densities. Herein, we report that the use of highly concentrated electrolytes composed of ether solvents and the lithium bis(fluorosulfonyl)imide (LiFSI) salt enables the high rate cycling of a Li metal anode at high CE (up to 99.1 %) without dendrite growth. With 4 M LiFSI in 1,2-dimethoxyethane (DME) as the electrolyte, a Li|Li cell can be cycled at high rates (10 mA cm-2) for more than 6000 cycles with no increase in the cell impedance, and a Cu|Li cell can be cycled at 4 mA cm-2 for more than 1000 cycles with an average CE of 98.4%. These excellent high rate performances can be attributed to the increased solvent coordination and increased availability of Li+ concentration in the electrolyte. Further development of this electrolyte may lead to practical applications for Li metal anode in rechargeable batteries. The fundamental mechanisms behind the high rate ion exchange and stability of the electrolytes also shine light on the stability of other electrochemical systems.

  19. High rate and stable cycling of lithium metal anode

    SciTech Connect (OSTI)

    Qian, Jiangfeng; Henderson, Wesley A.; Xu, Wu; Bhattacharya, Priyanka; Engelhard, Mark H.; Borodin, Oleg; Zhang, Jiguang

    2015-02-20

    Lithium (Li) metal is an ideal anode material for rechargeable batteries. However, dendritic Li growth and limited Coulombic efficiency (CE) during repeated Li deposition/stripping processes have prevented the application of this anode in rechargeable Li metal batteries, especially for use at high current densities. Here, we report that the use of highly concentrated electrolytes composed of ether solvents and the lithium bis(fluorosulfonyl)imide (LiFSI) salt enables the high rate cycling of a Li metal anode at high CE (up to 99.1 %) without dendrite growth. With 4 M LiFSI in 1,2-dimethoxyethane (DME) as the electrolyte, a Li|Li cell can be cycled at high rates (10 mA cm-2) for more than 6000 cycles with no increase in the cell impedance, and a Cu|Li cell can be cycled at 4 mA cm-2 for more than 1000 cycles with an average CE of 98.4%. These excellent high rate performances can be attributed to the increased solvent coordination and increased availability of Li+ concentration in the electrolyte. Lastly, further development of this electrolyte may lead to practical applications for Li metal anode in rechargeable batteries. The fundamental mechanisms behind the high rate ion exchange and stability of the electrolytes also shine light on the stability of other electrochemical systems.

  20. High rate and stable cycling of lithium metal anode

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

    Qian, Jiangfeng; Henderson, Wesley A.; Xu, Wu; Bhattacharya, Priyanka; Engelhard, Mark H.; Borodin, Oleg; Zhang, Jiguang

    2015-02-20

    Lithium (Li) metal is an ideal anode material for rechargeable batteries. However, dendritic Li growth and limited Coulombic efficiency (CE) during repeated Li deposition/stripping processes have prevented the application of this anode in rechargeable Li metal batteries, especially for use at high current densities. Here, we report that the use of highly concentrated electrolytes composed of ether solvents and the lithium bis(fluorosulfonyl)imide (LiFSI) salt enables the high rate cycling of a Li metal anode at high CE (up to 99.1 %) without dendrite growth. With 4 M LiFSI in 1,2-dimethoxyethane (DME) as the electrolyte, a Li|Li cell can be cycledmore » at high rates (10 mA cm-2) for more than 6000 cycles with no increase in the cell impedance, and a Cu|Li cell can be cycled at 4 mA cm-2 for more than 1000 cycles with an average CE of 98.4%. These excellent high rate performances can be attributed to the increased solvent coordination and increased availability of Li+ concentration in the electrolyte. Lastly, further development of this electrolyte may lead to practical applications for Li metal anode in rechargeable batteries. The fundamental mechanisms behind the high rate ion exchange and stability of the electrolytes also shine light on the stability of other electrochemical systems.« less

  1. Floating Rate Agreement | Department of Energy

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

    Floating Rate Agreement Floating Rate Agreement Floating Rate Agreement (99.85 KB) More Documents & Publications Fixed Rate Agreement Energy Efficiency Loan Program Agreement Template Energy Efficiency Loan Program Agreement-Template

  2. Fast repetition rate (FRR) flasher

    DOE Patents [OSTI]

    Kolber, Zbigniew; Falkowski, Paul

    1997-02-11

    A fast repetition rate (FRR) flasher suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between Successive discharges of the discharge capacitor. Advantageously, the control means is operable to discharge the discharge capacitor at a rate greater than 10,000 Hz and even up to a rate greater than about 250,000 Hz.

  3. Fast repetition rate (FRR) flasher

    DOE Patents [OSTI]

    Kolber, Z.; Falkowski, P.

    1997-02-11

    A fast repetition rate (FRR) flasher is described suitable for high flash photolysis including kinetic chemical and biological analysis. The flasher includes a power supply, a discharge capacitor operably connected to be charged by the power supply, and a flash lamp for producing a series of flashes in response to discharge of the discharge capacitor. A triggering circuit operably connected to the flash lamp initially ionizes the flash lamp. A current switch is operably connected between the flash lamp and the discharge capacitor. The current switch has at least one insulated gate bipolar transistor for switching current that is operable to initiate a controllable discharge of the discharge capacitor through the flash lamp. Control means connected to the current switch for controlling the rate of discharge of the discharge capacitor thereby to effectively keep the flash lamp in an ionized state between successive discharges of the discharge capacitor. Advantageously, the control means is operable to discharge the discharge capacitor at a rate greater than 10,000 Hz and even up to a rate greater than about 250,000 Hz. 14 figs.

  4. Variable gas leak rate valve

    DOE Patents [OSTI]

    Eernisse, Errol P.; Peterson, Gary D.

    1976-01-01

    A variable gas leak rate valve which utilizes a poled piezoelectric element to control opening and closing of the valve. The gas flow may be around a cylindrical rod with a tubular piezoelectric member encircling the rod for seating thereagainst to block passage of gas and for reopening thereof upon application of suitable electrical fields.

  5. Long-run growth rate in a random multiplicative model (Journal...

    Office of Scientific and Technical Information (OSTI)

    exponent limsub n1n log(xsub n), at fixed 12 tsub nn, and show that it is given by the equation of state of the lattice gas in thermodynamical equilibrium. ...

  6. Intercropping of two Leucaena spp. with sweet potato: yield, growth rate and biomass

    SciTech Connect (OSTI)

    Swift, J.F.

    1982-01-01

    Results of trials with Leucaena leucocephala and Leucaena diversifolia at Wau, Papua New Guinea, showed potential benefits of the agroforestry cropping system. The total biomass yield (sweet potato plus firewood and green manure) was considerably greater than the yield per unit area of sweet potato alone. 3 references.

  7. Vertical zone melt growth of GaAs

    SciTech Connect (OSTI)

    Henry, R.L.; Nordquist, P.E.R.; Gorman, R.J.

    1993-12-31

    A Vertical Zone Melt (VZM) technique has been applied to the single crystal growth of GaAs. A pyrolytic boron nitride crucible and a (100) oriented seed were used along with liquid encapsulation by boric oxide. In the case of GaAs, the ampoule was pressurized with either argon or argensic vapor from elemental arsenic at pressures ranging from 1 to 2 atmospheres. A molten zone length of 22 mm gave a growth interface which is nearly flat and resulted in routine single crystal growth. Temperature gradients of 4{degrees}C/cm. and 9{degrees}C/cm. have produced dislocation densities of <1000/cm{sup 2} and 2000-5000/cm{sup 2} respectively for 34 mm diameter crystals of GaAs. Post growth cooling rates for GaAs have been 35, 160 and 500{degrees}C/hr. The cooling rate has been found to affect the number and size of arsenic precipitates and the EL2 concentration in the GaAs crystal. The effects of these and other growth parameters on the crystalline perfection and electrical properties of the crystals will be discussed.

  8. Evaluation Ratings Definitions (Excluding Utilization of Small...

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

    (Excluding Utilization of Small Business) Rating Definition Note Exceptional ... Definitions (Utilization of Small Business) Rating Definition Note Exceptional ...

  9. Isotropic Monte Carlo Grain Growth

    Energy Science and Technology Software Center (OSTI)

    2013-04-25

    IMCGG performs Monte Carlo simulations of normal grain growth in metals on a hexagonal grid in two dimensions with periodic boundary conditions. This may be performed with either an isotropic or a misorientation - and incliantion-dependent grain boundary energy.

  10. Fatigue crack growth behavior of Al-Li alloy 1441

    SciTech Connect (OSTI)

    Prakash, R.V.; Parida, B.K.

    1995-12-31

    Fatigue crack growth behavior of Al-Li alloy 1441 having a marginally lower lithium content, compared to 80xx and 20xx series Al-Li alloys is presented in this paper. This investigation was conducted on single edge tension--SE(T)--specimens, under constant amplitude as well as under MiniLCA flight spectrum loading with the specific objective of determining the effects of stress ratio, orientation, thickness and cladding. Three thicknesses were considered: 1.2 mm(clad and unclad), 2.0 mm(clad and unclad) and 8.0 mm unclad. Constant amplitude fatigue tests were conducted at stress ratios of {minus}0.3, 0.1 and 0.7. Testing was performed under ambient conditions and along three orientations, namely L-T, T-L and L+45 degrees. Crack growth characteristics of this alloy are compared with that of BS:L73 (2014-T4 equivalent) for assessing the possibility of replacing BS:L73. Significant effect of stress ratio on crack growth rate was observed in all thicknesses. However, in case of 1.2 and 2.0 mm thick sheets, the effect was minimal at intermediate-crack growth regime. The orientation of the specimen does not adversely affect the fatigue crack growth behavior of 8.0 mm and 2.0 mm thick specimens. However, for 1.2 mm unclad sheet crack growth resistance in L-T direction was found to be superior to that along T-L direction. In majority of test cases considered, no significant effect was observed on crack growth rate due to thickness or cladding. Crack growth characteristics of Al-Li alloy 1441 and Al-Cu alloy BS:L73 under constant amplitude as well as MiniLCA spectrum loading are similar in the low and intermediate-crack growth rate regime. Based on these observations, it is felt that this Al-Li alloy has the potential for future aerospace applications.

  11. Impact of Rate Design Alternatives on Residential Solar Customer Bills. Increased Fixed Charges, Minimum Bills and Demand-based Rates

    SciTech Connect (OSTI)

    Bird, Lori; Davidson, Carolyn; McLaren, Joyce; Miller, John

    2015-09-01

    With rapid growth in energy efficiency and distributed generation, electric utilities are anticipating stagnant or decreasing electricity sales, particularly in the residential sector. Utilities are increasingly considering alternative rates structures that are designed to recover fixed costs from residential solar photovoltaic (PV) customers with low net electricity consumption. Proposed structures have included fixed charge increases, minimum bills, and increasingly, demand rates - for net metered customers and all customers. This study examines the electricity bill implications of various residential rate alternatives for multiple locations within the United States. For the locations analyzed, the results suggest that residential PV customers offset, on average, between 60% and 99% of their annual load. However, roughly 65% of a typical customer's electricity demand is non-coincidental with PV generation, so the typical PV customer is generally highly reliant on the grid for pooling services.

  12. 1993 Wholesale Power and Transmission Rate Schedules.

    SciTech Connect (OSTI)

    US Bonneville Power Administration

    1993-10-01

    Bonneville Power Administration 1993 Wholesale Power Rate Schedules and General Rate Schedule Provisions and 1993 Transmission Rate Schedules and General Transmission Rate Schedule Provisions, contained herein, were approved on an interim basis effective October 1, 1993. These rate schedules and provisions were approved by the Federal Energy Commission, United States Department of Energy, in September, 1993. These rate schedules and provisions supersede the Administration`s Wholesale Power Rate Schedules and General Rate Schedule Provisions and Transmission Rate Schedules and General Transmission Rate Schedule Provisions effective October 1, 1991.

  13. Economic Effects of High Oil Prices (released in AEO2006)

    Reports and Publications (EIA)

    2006-01-01

    The Annual Energy Outlook 2006 projections of future energy market conditions reflect the effects of oil prices on the macroeconomic variables that affect oil demand, in particular, and energy demand in general. The variables include real gross domestic product (GDP) growth, inflation, employment, exports and imports, and interest rates.

  14. High Rate and Stable Cycling of Lithium Metal Anode - Joint Center for

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

    Energy Storage Research November 10, 2014, Research Highlights High Rate and Stable Cycling of Lithium Metal Anode Coulombic efficiency (CE) of Li plating/stripping is > 99.1% in concentrated LiFSI-DME electrolyte Scientific Achievement Lithium metal is an ideal battery anode. However, dendrite growth and limited CE during cycling have limited its practical applications. High CE (up to 99.1%) without dendrite growth is achieved by using highly concentrated electrolytes for lithium

  15. Controlled VLS Growth of Indium, Gallium and Tin Oxide Nanowiresvia Chemical Vapor Transport

    SciTech Connect (OSTI)

    Johnson, M.C.; Aloni, S.; McCready, D.E.; Bourret-Courchesne, E.D.

    2006-03-13

    We utilized a vapor-liquid-solid growth technique to synthesize indium oxide, gallium oxide, and tin oxide nanowires using chemical vapor transport with gold nanoparticles as the catalyst. Using identical growth parameters we were able to synthesize single crystal nanowires typically 40-100 nm diameter and more than 10-100 microns long. The products were characterized by means of XRD, SEM and HRTEM. All the wires were grown under the same growth conditions with growth rates inversely proportional to the source metal vapor pressure. Initial experiments show that different transparent oxide nanowires can be grown simultaneously on a single substrate with potential application for multi-component gas sensors.

  16. Lid for improved dendritic web growth

    DOE Patents [OSTI]

    Duncan, Charles S.; Kochka, Edgar L.; Piotrowski, Paul A.; Seidensticker, Raymond G.

    1992-03-24

    A lid for a susceptor in which a crystalline material is melted by induction heating to form a pool or melt of molten material from which a dendritic web of essentially a single crystal of the material is pulled through an elongated slot in the lid and the lid has a pair of generally round openings adjacent the ends of the slot and a groove extends between each opening and the end of the slot. The grooves extend from the outboard surface of the lid to adjacent the inboard surface providing a strip contiguous with the inboard surface of the lid to produce generally uniform radiational heat loss across the width of the dendritic web adjacent the inboard surface of the lid to reduce thermal stresses in the web and facilitate the growth of wider webs at a greater withdrawal rate.

  17. What Is the Right Rate? Loan Rates and Demand | Department of...

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

    Is the Right Rate? Loan Rates and Demand What Is the Right Rate? Loan Rates and Demand Better Buildings Neighborhood Program Financing Peer Exchange Call: "What is the Right Rate?" ...

  18. Conditioning biomass for microbial growth (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Conditioning biomass for microbial growth Title: Conditioning biomass for microbial growth You are accessing a document from the Department of Energy's (DOE) DOE Patents. This ...

  19. Aerosynthesis: Growths of Vertically Aligned Carbon Nanofibers...

    Office of Scientific and Technical Information (OSTI)

    Aerosynthesis: Growths of Vertically Aligned Carbon Nanofibers with Air DC Plasma Citation Details In-Document Search Title: Aerosynthesis: Growths of Vertically Aligned Carbon ...

  20. Exploring growth kinetics of carbon nanotube arrays by in situ optical diagnostics and modeling

    SciTech Connect (OSTI)

    Puretzky, Alexander A; Geohegan, David B; Pannala, Sreekanth; Rouleau, Christopher

    2014-01-01

    Simple kinetic models of carbon nanotube growth have been able to successfully link together many experimental parameters involved in the growth of carbon nanotubes for practical applications including the prediction of growth rates, terminal lengths, number of walls, activation energies, and their dependences on the growth environment. The implications of recent experiments utilizing in situ monitoring of carbon nanotube growth on our past kinetic model are first reviewed. Then, sub-second pulsed feedstock gas introduction is discussed to explore the nucleation and initial growth of carbon nanotubes in the context of the kinetic model. Moreover, kinetic effects in "pulsed CVD" - using repeated pulsed gas introduction to stop and restart nanotube growth - are explored to understand renucleation, the origin of alignment in nanotube arrays, and incremental growth. Time-resolved reflectivity of the surface is used to remotely understand the kinetics of nucleation and the coordinated growth of arrays. This approach demonstrates that continuous vertically aligned single wall carbon nanotubes can be grown incrementally by pulsed CVD, and that the first exposure of fresh catalyst to feedstock gas is critical to nanotubes site density required for coordinated growth. Aligned nanotube arrays (as short as 60 nm) are shown to nucleate and grow within single, sub-second gas pulses. The multiple-pulse growth experiments (> 100 pulses) show that a high fraction of nanotubes renucleate on subsequent gas pulses.

  1. Modeling carbon nanotube growth on the catalyst-substrate surface subjected to reactive plasma [

    SciTech Connect (OSTI)

    Tewari, Aarti; Sharma, Suresh C.

    2014-06-15

    The paper presents a theoretical model to study the growth of the carbon nanotube (CNT) on the catalyst substrate surface subjected to reactive plasma. The charging rate of the CNT, kinetics of electron, ions and neutral atoms, the growth rate of the CNT because of diffusion and accretion of ions on the catalyst nanoparticle inclusion of the issue of the plasma sheath is undertaken in the present model. Numerical calculations on the effect of ion density and temperature and the substrate bias on the growth of the CNT have been carried out for typical glow discharge plasma parameters. It is found that the height of CNT increases with the ion density of carbon ions and radius of CNT decreases with hydrogen ion density. The substrate bias also affects the growth rate of the CNT. The field emission characteristics from the CNTs can be analyzed from the results obtained.

  2. Growth of filaments and saturation of the filamentation instability

    SciTech Connect (OSTI)

    Gedalin, M.; Medvedev, M.; Spitkovsky, A.; Krasnoselskikh, V.; Vaivads, A.; Perri, S.

    2010-03-15

    The filamentation instability of counterstreaming beams is a nonresonant hydrodynamic-type instability whose growth rate is a smooth function of the wavelength (scale). As a result, perturbations with all unstable wavelengths develop, and the growth saturates due to the saturation of available current. For a given scale, the magnetic field at saturation is proportional to the scale. As a result, the instability develops in a nearly linear regime, where the unstable modes stop growing as soon as the saturation of the corresponding wavelength is reached. At each moment there exists a dominant scale of the magnetic field which is the scale that reached saturation at this particular time. The smaller scales do not disappear and can be easily distinguished in the current structure. The overall growth of the instability stops when the loss of the streaming ion energy because of deceleration is comparable to the initial ion energy.

  3. Computer Simulation of Bubble Growth in Metals Due to He

    SciTech Connect (OSTI)

    FOILES, STEPHEN M.; HOYT, JEFFREY J.

    2001-03-01

    Atomistic simulations of the growth of helium bubbles in metals are performed. The metal is represented by embedded atom method potentials for palladium. The helium bubbles are treated via an expanding repulsive spherical potential within the metal lattice. The simulations predict bubble pressures that decrease monotonically with increasing helium to metal ratios. The swelling of the material associated with the bubble growth is also computed. It is found that the rate of swelling increases with increasing helium to metal ratio consistent with experimental observations on the swelling of metal tritides. Finally, the detailed defect structure due to the bubble growth was investigated. Dislocation networks are observed to form that connect the bubbles. Unlike early model assumptions, prismatic loops between the bubbles are not retained. These predictions are compared to available experimental evidence.

  4. Rating fenestration for energy efficiency

    SciTech Connect (OSTI)

    Markway, R.

    1993-09-01

    The grading of windows and doors by the National Fenestration Rating Council (NFRC) opens a new era regarding the energy efficiency of fenestration products. For the first time, architects, designers, and other specifiers will find themselves on a level playing field when it comes to comparing the thermal performance of fenestration products. Although only one state, California, now requires the use of fenestration products that have gone through the NFRC's simulation and testing procedures, five other states will soon be doing so, including Washington, Alaska, Oregon, Idaho, and Wisconsin. Others will follow suit; Florida, Arizona, Texas, Louisiana, New York, Massachusetts, and Colorado have shown interest. Exactly what does this mean to architects The NFRC, which was established last year, has developed a procedure to determine accurately the U-value of fenestration products. Under the NFRC program a number of independent simulation and testing laboratories have been approved. These laboratories are charged with the responsibility of determining whether products conform to the U-values represented by the manufacturers. The rating procedure and benefits from it are described.

  5. Wholesale Power Rate Schedules | Department of Energy

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

    Power Rate Schedules October 1, 2011 CBR-1-H Wholesale Power Rate Schedule Area: Big Rivers and Henderson, KY System: CU October 1, 2011 CM-1-H Wholesale Power Rate...

  6. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: electric load data Type Term Title Author Replies Last Post sort icon...

  7. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: DOE Type Term Title Author Replies Last Post sort icon Blog entry DOE...

  8. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: API Type Term Title Author Replies Last Post sort icon Blog entry API...

  9. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: EZFeed Type Term Title Author Replies Last Post sort icon Blog entry...

  10. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: Database Type Term Title Author Replies Last Post sort icon Blog entry...

  11. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: bug Type Term Title Author Replies Last Post sort icon Discussion bug...

  12. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: energy efficiency Type Term Title Author Replies Last Post sort icon...

  13. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: clean energy Type Term Title Author Replies Last Post sort icon Blog...

  14. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: datasets Type Term Title Author Replies Last Post sort icon Blog entry...

  15. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: FOA Type Term Title Author Replies Last Post sort icon Blog entry FOA...

  16. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: Illinois State University Type Term Title Author Replies Last Post sort...

  17. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: building load Type Term Title Author Replies Last Post sort icon Blog...

  18. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: building load data Type Term Title Author Replies Last Post sort icon...

  19. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: dataset Type Term Title Author Replies Last Post sort icon Blog entry...

  20. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: Energy Visions Prize Type Term Title Author Replies Last Post sort icon...

  1. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: funding Type Term Title Author Replies Last Post sort icon Blog entry...

  2. Utility Rate | OpenEI Community

    Open Energy Info (EERE)

    Rate Home > Utility Rate > Posts by term > Utility Rate Content Group Activity By term Q & A Feeds Term: EIA Type Term Title Author Replies Last Post sort icon Blog entry EIA...

  3. On the origin of radiation growth of hcp crystals

    SciTech Connect (OSTI)

    Golubov, Stanislav I; Barashev, Aleksandr; Stoller, Roger E

    2012-03-01

    The aim of the present work is to study theoretically the radiation growth (RG) of hcp-type materials with a particular focus on the effect of one-dimensionally (1-D) migrating clusters of self-interstitial atoms (SIAs), which are steadily produced in displacement cascades under neutron or heavy-ion irradiation. A reaction-diffusion model is developed for the description of RG in single hcp-type metallic crystals. The model reproduces all RG stages observed in neutron-irradiated annealed samples of pure Zr and Zr alloys, such as high strain rate at low, strain saturation at intermediate and breakaway growth at relatively high irradiation doses. In addition, it accounts for the striking observations of negative strains in prismatic directions and coexistence of vacancy- and SIA-type prismatic loops. The role of cold work in RG behavior and alignment of the vacancy-type loops along basal planes are revealed and the maximum strain rate is estimated.

  4. Digital electronic bone growth stimulator

    DOE Patents [OSTI]

    Kronberg, James W.

    1995-01-01

    A device for stimulating bone tissue by applying a low level alternating current signal directly to the patient's skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures.

  5. Nonlinear structural crack growth monitoring

    DOE Patents [OSTI]

    Welch, Donald E.; Hively, Lee M.; Holdaway, Ray F.

    2002-01-01

    A method and apparatus are provided for the detection, through nonlinear manipulation of data, of an indicator of imminent failure due to crack growth in structural elements. The method is a process of determining energy consumption due to crack growth and correlating the energy consumption with physical phenomena indicative of a failure event. The apparatus includes sensors for sensing physical data factors, processors or the like for computing a relationship between the physical data factors and phenomena indicative of the failure event, and apparatus for providing notification of the characteristics and extent of such phenomena.

  6. Digital electronic bone growth stimulator

    DOE Patents [OSTI]

    Kronberg, J.W.

    1995-05-09

    A device is described for stimulating bone tissue by applying a low level alternating current signal directly to the patient`s skin. A crystal oscillator, a binary divider chain and digital logic gates are used to generate the desired waveforms that reproduce the natural electrical characteristics found in bone tissue needed for stimulating bone growth and treating osteoporosis. The device, powered by a battery, contains a switch allowing selection of the correct waveform for bone growth stimulation or osteoporosis treatment so that, when attached to the skin of the patient using standard skin contact electrodes, the correct signal is communicated to the underlying bone structures. 5 figs.

  7. utility rate | OpenEI Community

    Open Energy Info (EERE)

    utility Utility Companies utility rate Utility Rates version 1 version 2 version 3 web service Smart meter After several months of development and testing, the next...

  8. LB CRAC Workshops (rates/meetings)

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

    Load-Based (LB) CRAC Power Rate Adjustment Workshop Materials Related Links: Power Rate Adjustments > Load-Based (LB) CRAC December 13, 2006 LB CRAC Workshop Materials (updated...

  9. Residential Solar Valuation Rates | Department of Energy

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

    Residential Solar Valuation Rates Residential Solar Valuation Rates This presentation summarizes the information discussed by Rabago Energy during the Best Practices in the Design ...

  10. Atomistic mechanisms for bilayer growth of graphene on metal substrates

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

    Chen, Wei; Cui, Ping; Zhu, Wenguang; Kaxiras, Efthimios; Gao, Yanfei; Zhang, Zhenyu

    2015-01-08

    Epitaxial growth on metal substrates has been shown to be the most powerful approach in producing large-scale high-quality monolayer graphene, yet it remains a major challenge to realize uniform bilayer graphene growth. Here we carry out a comparative study of the atomistic mechanisms for bilayer graphene growth on the (111) surfaces of Cu and Ni, using multiscale approaches combining first-principles calculations and rate-equation analysis. We first show that the relatively weak graphene-Cu interaction enhances the lateral diffusion and effective nucleation of C atoms underneath the graphene island, thereby making it more feasible to grow bilayer graphene on Cu. In contrast,more » the stronger graphene-Ni interaction suppresses the lateral mobility and dimerization of C atoms underneath the graphene, making it unlikely to achieve controlled growth of bilayer graphene on Ni. We then determine the critical graphene size beyond which nucleation of the second layer will take place. Intriguingly, the critical size exhibits an effective inverse "Ehrlich-Schwoebel barrier" effect, becoming smaller for faster C migration from the Cu surface to the graphene-Cu interface sites across the graphene edge. Lastly, these findings allow us to propose a novel alternating growth scheme to realize mass production of bilayer graphene.« less