Sample records for abundant power solutions

  1. Abundant Power | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDITCaliforniaWeifangwiki HomeASN Power ProjectsAbraham HotAbundant Power

  2. Remote power -- Integrated, customer oriented solutions

    SciTech Connect (OSTI)

    Jordan, D.; Twidell, M.; Patel, J.; Teofilo, F.; Soin, R. [BP Solar Australia, Brookvale, New South Wales (Australia)

    1994-12-31T23:59:59.000Z

    Throughout its history, BP Solar has focused strongly on the production of integrated power solutions to it`s customers, using photovoltaics as the central, but not unique, technology. This paper discusses the customer driven development of two new generation hybrid power systems, one AC the other DC. Both involve the combination of renewable energy with a conventional power source in a fully integrated system, as well as providing remote electronic system access, advanced data and event logging, and comprehensive computer graphic analysis software. The first is a DC system providing power to telecommunication authorities in the Asian-Pacific region, the second is generating abundant high quality AC power for Australian domestic users.

  3. Fractal powers in Serrin's swirling vortex solutions

    E-Print Network [OSTI]

    Pavel B?lík; Douglas P. Dokken; Kurt Scholz; Mikhail M. Shvartsman

    2014-04-28T23:59:59.000Z

    We consider a modification of the fluid flow model for a tornado-like swirling vortex developed by J. Serrin, where velocity decreases as the reciprocal of the distance from the vortex axis. Recent studies, based on radar data of selected severe weather events, indicate that the angular momentum in a tornado may not be constant with the radius, and thus suggest a different scaling of the velocity/radial distance dependence. Motivated by this suggestion, we consider Serrin's approach with the assumption that the velocity decreases as the reciprocal of the distance from the vortex axis to the power $b$ with a general $b>0$. This leads to a boundary-value problem for a system of nonlinear differential equations. We analyze this problem for particular cases, both with nonzero and zero viscosity, discuss the question of existence of solutions, and use numerical techniques to describe those solutions that we cannot obtain analytically.

  4. Nuclear Power No Solution to the Climate Crisis

    E-Print Network [OSTI]

    Laughlin, Robert B.

    Nuclear Power No Solution to the Climate Crisis Michael Mariotte Nuclear Information and Resource-12, 2009 #12;Environmental Statement on Nuclear Power and the Climate Crisis "We do not support emissions than nuclear power." Signed by 483 US organizations, 164 int'l organizations and 10

  5. SECOND GENERATION REFORMS IN CHILE, POWER EXCHANGE MODEL. THE SOLUTION?

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    their electric power systems, encouraging competition in generation and allowing private investments organizations, the Power Exchange (PX) and the Independent System Operator (ISO). Based on the electricitySECOND GENERATION REFORMS IN CHILE, POWER EXCHANGE MODEL. THE SOLUTION? David Watts Paulo Atienza

  6. PowerIt Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,Pillar Group BV Jump to: navigation,Power Rental Market SizePowerGenix

  7. Infinite Power Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluatingGroup | OpenHunan Runhua NewSmallholderEconomyIndustrias MorroInfinite Power

  8. Renewable power needs smart storage solutions

    SciTech Connect (OSTI)

    Madison, Alison L.

    2010-10-24T23:59:59.000Z

    Ancient Greek philosopher Heraclitus claimed that the only thing constant in life is change, a truth we must accept and even celebrate. Another truth we face today is a growing demand for more energy to help us power the kind and pace of change we’ve become accustomed to, while minimizing environmental consequences. Renewable energy--two words that often find themselves woven into environmentally conscious dialogue. And according to Dave Lucero, director of alternative energy storage at EaglePicher Technologies LLC, the Tri-Cities should be thinking about two more: energy storage. Lucero recently addressed the Tri-Cities Research District about tackling the persistent challenge of maximizing renewable energy, which is inherently variable due to changing weather patterns. Capturing that energy and making it available for later use is vital.

  9. 21st century energy solutions. Coal and Power Systems FY2001 program briefing

    SciTech Connect (OSTI)

    None

    2001-01-01T23:59:59.000Z

    The continued strength of American's economy depends on the availability of affordable energy, which has long been provided by the Nations rich supplies of fossil fuels. Forecasts indicate that fossil fuels will continue to meet much of the demand for economical electricity and transportation fuels for decades to come. It is projected that natural gas, oil, and coal will supply nearly 90% of US energy in 2020, with coal fueling around 50% of the electricity. It is essential to develop ways to achieve the objectives for a cleaner environment while using these low-cost, high-value fuels. A national commitment to improved technologies--for use in the US and abroad--is the solution. The Coal and Power Systems program is responding to this commitment by offering energy solutions to advance the clean, efficient, and affordable use of the Nations abundant fossil fuel resources. These solutions include: (1) Vision 21--A multi-product, pollution-free energy plant--producing electricity, fuels, and/or industry heat--could extract 80% or more of the energy value of coal and 85% or more of the energy value of natural gas; (2) Central Power Systems--Breakthrough turbines and revolutionary new gasification technologies that burn less coal and gas to obtain energy, while reducing emissions; (3) Distributed Generation--Fuel cell technology providing highly efficient, clean modular power; (4) Fuels--The coproduction of coal-derived transportation fuels and power from gasification-based technology; (5) Carbon Sequestration--Capturing greenhouse gases from the exhaust gases of combustion or other sources, or from the atmosphere itself, and storing them for centuries or recycling them into useful products; and (6) Advanced Research--Going beyond conventional thinking in the areas of computational science, biotechnology, and advanced materials.

  10. LM4651 & LM4652 OvertureTM Audio Power Amplifier 170W Class D Audio Power Amplifier Solution

    E-Print Network [OSTI]

    Paderborn, Universität

    and minimizes supply current. The LM4652 is a fully integrated H-bridge power MOSFET IC in a TO-220 power trademark of National Semiconductor Corporation. LM4651 Plastic Package DS101277-72 Top View Order Number LMDAudioPowerAmplifierSolution © 2000 National Semiconductor Corporation DS101277 www.national.com #12;Absolute Maximum Ratings (Notes 1

  11. SRP- PowerWise Business Solutions Energy Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    SRPBusiness Solutions is a program designed to help SRP business customers manage energy usage and increase the energy efficiency of participating facilities. Within this program there are several...

  12. Edinburgh Research Explorer Local solutions of the optimal power flow problem

    E-Print Network [OSTI]

    Millar, Andrew J.

    law (KVL), which describes the flow of power in transmission lines, and is a nonlinear function of bus is to find a steady state operating point that minimizes the cost of electric power generation whileEdinburgh Research Explorer Local solutions of the optimal power flow problem Citation

  13. Innovative Phase hange Thermal Energy Storage Solution for Baseload Power

    Broader source: Energy.gov [DOE]

    This presentation was delivered at the SunShot Concentrating Solar Power (CSP) Program Review 2013, held April 23–25, 2013 near Phoenix, Arizona.

  14. Comments of Climate Solutions Northwest Power and Conservation Council's

    E-Print Network [OSTI]

    -effectively saves more power than Idaho uses, with economic savings of $500 million or more per year. This is by far shocks were mitigated to some degree by energy savings. But taking our eye off the efficiency ball

  15. Burbank Water and Power- Energy Solutions Business Rebate Program

    Broader source: Energy.gov [DOE]

    Burbank Water and Power offers a rebate to business customers for installing energy efficient equipment in eligible facilities. The rebate is offered for a variety of energy efficient measures and...

  16. Solution to plasma-etching puzzle could mean more powerful microchips...

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

    Solution to plasma-etching puzzle could mean more powerful microchips By John Greenwald February 11, 2014 Tweet Widget Google Plus One Share on Facebook An integrated-circuit...

  17. DC Optimal Power Flow Formulation and Solution Using QuadProgJ

    E-Print Network [OSTI]

    Tesfatsion, Leigh

    , still retaining an SCQP form, so that solution values for voltage angles and locational marginal prices power injections. However, solution values for locational marginal prices (LMPs), voltage angles, Chen-Ching Liu, Jim McCalley, Michael J. D. Powell, Jim Price, Harold Salazar, Johnny Wong, and Tong Wu

  18. ILP and Iterative LP Solutions for Peak and Average Power Optimization in HLS

    E-Print Network [OSTI]

    Ramanujam, J. "Ram"

    . Ramanujam2 1 Electrical Engineering Dept., Assiut University, Egypt 2 Electrical and Computer Engineering as average power and energy consumptions. As the design problem becomes large, exact solution takes-flow graph (DFG) executes. We define Scheduling for Low Power and Energy (SLoPE) in high-level synthesis

  19. SunPower Italia formerly Solar Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty Edit with formSoutheastern IL ElecStrategicStoriesSunJoi Solar Inc JumpSunPower Italia

  20. Battery Energy Power Solutions Pty Ltd | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof EnergyInnovation in Carbon CaptureAtriaPower SystemsRhode Island:

  1. Emission Power Solutions Plc EPS | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489 No revision| OpenElectromagneticElmwood CUSD JumpEmigrantPower

  2. SOLUTIONS

    E-Print Network [OSTI]

    2012-07-04T23:59:59.000Z

    MA 162 - Quiz 5 (20 minutes). SOLUTIONS. The solutions I present are not necessarily the only solutions. As long as you give a correct method of solving a ...

  3. A SELF-POWERED, SELF-SUSTAINING SYSTEM-ON-CHIP (SOC) SOLUTION POWERED FROM HYBRID MICRO-FUEL CELLS

    E-Print Network [OSTI]

    Rincon-Mora, Gabriel A.

    -on-ship (SOC) solution with fully integrated micro-fuel cell/thin-film lithium-ion battery hybrids. A power scheme is proposed whereby micro-fuel cells charge an in-package thin-film lithium-ion battery, which temperatures (e.g., 0-85ºC) and only emergent micro-fuel cells (Kohl, 2004) and thin-film lithium-ion batteries

  4. Numerical Polynomial Homotopy Continuation Method to Locate All The Power Flow Solutions

    E-Print Network [OSTI]

    Dhagash Mehta; Hung Nguyen; Konstantin Turitsyn

    2014-08-12T23:59:59.000Z

    The manuscript addresses the problem of finding all solutions of power flow equations or other similar nonlinear system of algebraic equations. This problem arises naturally in a number of power systems contexts, most importantly in the context of direct methods for transient stability analysis and voltage stability assessment. We introduce a novel form of homotopy continuation method called the numerical polynomial homotopy continuation (NPHC) method that is mathematically guaranteed to find all the solutions without ever encountering a bifurcation. The method is based on embedding the real form of power flow equation in complex space, and tracking the generally unphysical solutions with complex values of real and imaginary parts of the voltage. The solutions converge to physical real form in the end of the homotopy. The so-called $\\gamma$-trick mathematically rigorously ensures that all the paths are well-behaved along the paths, so unlike other continuation approaches, no special handling of bifurcations is necessary. The method is \\textit{embarrassingly parallelizable} and can be applied to reasonably large sized systems. We demonstrate the technique by analysis of several standard test cases up to the 14-bus system size. Finally, we discuss possible strategies for scaling the method to large size systems, and propose several applications for transient stability analysis and voltage stability assessment.

  5. Engineering Density of States of Earth Abundant Semiconductors...

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

    of States of Earth Abundant Semiconductors for Enhanced Thermoelectric Power Factor Engineering Density of States of Earth Abundant Semiconductors for Enhanced Thermoelectric...

  6. Local Solutions of Optimal Power Flow Waqquas A. Bukhsh, Andreas Grothey, Ken McKinnon, and Paul Trodden

    E-Print Network [OSTI]

    Grothey, Andreas

    is primarily due to Kirchhoff's voltage law (KVL), which describes the flow of power in transmission lines that minimizes the cost of electric power generation while satisfying operating constraints and meeting demandLocal Solutions of Optimal Power Flow Waqquas A. Bukhsh, Andreas Grothey, Ken McKinnon, and Paul

  7. HYDROGEN STORAGE SOLUTIONS IN SUPPORT OF DOD WARFIGHTER PORTABLE POWER APPLICATIONS

    SciTech Connect (OSTI)

    Motyka, T.

    2009-01-06T23:59:59.000Z

    From Personal Digital Assistants (PDAs) to cell phones our high-tech world, today, is demanding smaller, lighter weight and higher capacity portable power devices. Nowhere has this personal power surge been more evident than in today's U.S Warfighter. The modern Warfighter is estimated to carry from 65 to 95 pounds of supplies in the field with over 30 pounds of this dedicated to portable power devices. These devices include computer displays, infrared sights, Global Positioning Systems (GPS), night vision and a variety of other sensor technologies. Over 80% of the energy needed to power these devices comes from primary (disposable) batteries. It is estimated that a brigade will consume as much as 7 tons of batteries in a 72 hour mission at a cost of $700,000. A recent comprehensive study on the energy needs of the future warrior published by the National Academy of Science in 2004 made a variety of recommendations for average power systems from 20 to 1,000 watts. For lower power systems recommendations included pursuing science and technology initiatives focused on: (1) 300 watt-hours per kilogram (Wh/kg) secondary battery technologies; (2) smart hybrids; and (3) fuel cells (with greater than 6 wt% hydrogen storage). Improved secondary (rechargeable) batteries may be the ideal solution for military power systems due to their ease of use and public acceptance. However, a 3X improvement in their specific energy density is not likely anytime soon. Today's Lithium Ion batteries, at about 150 Wh/kg, fall well short of the energy density that is required. Future battery technology may not be the answer since many experts do not predict more than a 2X improvement in Lithium battery systems over the next 10 years. That is why most auto companies have abandoned all electric vehicles in favor of fuel cells and hybrid vehicles. Fuel cells have very high specific energy densities but achieving high energy values will depend on the energy density and the storage method of its fuel. Improved methods of safely and efficiently storing larger amounts of hydrogen will be a key development area for portable fuel cell power systems. Despite their high potential energy, fuel cells exhibit low power densities. That is why many systems today are going hybrid. Hybrid systems typically combine low energy and high power components with high energy and low power components. Typical configurations include capacitors and fuel cells or batteries and fuel cells. If done correctly, a hybrid system often can have both high energy and high power density even higher than any of the individual components.

  8. The analytic solution for the power series expansion of Heun function

    SciTech Connect (OSTI)

    Choun, Yoon Seok, E-mail: ychoun@gmail.com

    2013-11-15T23:59:59.000Z

    The Heun function generalizes all well-known special functions such as Spheroidal Wave, Lame, Mathieu, and hypergeometric {sub 2}F{sub 1}, {sub 1}F{sub 1} and {sub 0}F{sub 1} functions. Heun functions are applicable to diverse areas such as theory of black holes, lattice systems in statistical mechanics, solution of the Schrödinger equation of quantum mechanics, and addition of three quantum spins. In this paper I will apply three term recurrence formula (Y.S. Choun, (arXiv:1303.0806), 2013) to the power series expansion in closed forms of Heun function (infinite series and polynomial) including all higher terms of A{sub n}’s. Section 3 contains my analysis on applying the power series expansions of Heun function to a recent paper (R.S. Maier, Math. Comp. 33 (2007) 811–843). Due to space restriction final equations for the 192 Heun functions are not included in the paper, but feel free to contact me for the final solutions. Section 4 contains two additional examples using the power series expansions of Heun function. This paper is 3rd out of 10 in series “Special functions and three term recurrence formula (3TRF)”. See Section 5 for all the papers in the series. The previous paper in series deals with three term recurrence formula (3TRF). The next paper in the series describes the integral forms of Heun function and its asymptotic behaviors analytically. -- Highlights: •Power series expansion for infinite series of Heun function using 3 term rec. form. •Power series for polynomial which makes B{sub n} term terminated of Heun function. •Applicable to areas such as the Teukolsky equation in Kerr–Newman–de Sitter geometries.

  9. 344 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 23, NO. 2, MAY 2008 Economic Consequences of Alternative Solution

    E-Print Network [OSTI]

    Oren, Shmuel S.

    and differences to some extent. Index Terms--Electricity market design, power systems eco- nomics, unit commitment344 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 23, NO. 2, MAY 2008 Economic Consequences of Alternative Solution Methods for Centralized Unit Commitment in Day-Ahead Electricity Markets Ramteen

  10. Solution

    E-Print Network [OSTI]

    2011-09-09T23:59:59.000Z

    Solution: We're looking for the presale cost of the shirt, so let x be the price of ... The sale price is $10 and we've called the presale price x, so we need to solve.

  11. Combined Heat and Power: Effective Energy Solutions for a Sustainable Future

    SciTech Connect (OSTI)

    Shipley, Ms. Anna [Sentech, Inc.; Hampson, Anne [Energy and Environmental Analysis, Inc., an ICF Company; Hedman, Mr. Bruce [Energy and Environmental Analysis, Inc., an ICF Company; Garland, Patricia W [ORNL; Bautista, Paul [Sentech, Inc.

    2008-12-01T23:59:59.000Z

    Combined Heat and Power (CHP) solutions represent a proven and effective near-term energy option to help the United States enhance energy efficiency, ensure environmental quality, promote economic growth, and foster a robust energy infrastructure. Using CHP today, the United States already avoids more than 1.9 Quadrillion British thermal units (Quads) of fuel consumption and 248 million metric tons of carbon dioxide (CO{sub 2}) emissions annually compared to traditional separate production of electricity and thermal energy. This CO{sub 2} reduction is the equivalent of removing more than 45 million cars from the road. In addition, CHP is one of the few options in the portfolio of energy alternatives that combines environmental effectiveness with economic viability and improved competitiveness. This report describes in detail the four key areas where CHP has proven its effectiveness and holds promise for the future as an: (1) Environmental Solution: Significantly reducing CO{sub 2} emissions through greater energy efficiency; (2) Competitive Business Solution: Increasing efficiency, reducing business costs, and creating green-collar jobs; (3) Local Energy Solution: Deployable throughout the US; and (4) Infrastructure Modernization Solution: Relieving grid congestion and improving energy security. CHP should be one of the first technologies deployed for near-term carbon reductions. The cost-effectiveness and near-term viability of widespread CHP deployment place the technology at the forefront of practical alternative energy solutions such as wind, solar, clean coal, biofuels, and nuclear power. Clear synergies exist between CHP and most other technologies that dominate the energy and environmental policy dialogue in the country today. As the Nation transforms how it produces, transports, and uses the many forms of energy, it must seize the clear opportunity afforded by CHP in terms of climate change, economic competitiveness, energy security, and infrastructure modernization. The energy efficiency benefits of CHP offer significant, realistic solutions to near- and long-term energy issues facing the Nation. With growing demand for energy, tight supply options, and increasing environmental constraints, extracting the maximum output from primary fuel sources through efficiency is critical to sustained economic development and environmental stewardship. Investment in CHP would stimulate the creation of new 'green-collar' jobs, modernize aging energy infrastructure, and protect and enhance the competitiveness of US manufacturing industries. The complementary roles of energy efficiency, renewable energy, and responsible use of traditional energy supplies must be recognized. CHP's proven performance and potential for wider use are evidence of its near-term applicability and, with technological improvements and further elimination of market barriers, of its longer term promise to address the country's most important energy and environmental needs. A strategic approach is needed to encourage CHP where it can be applied today and address the regulatory and technical challenges preventing its long-term viability. Experience in the United States and other countries shows that a balanced set of policies, incentives, business models, and investments can stimulate sustained CHP growth and allow all stakeholders to reap its many well-documented benefits.

  12. Energy and Society (ER100/PP184/ER200/PP284) Fall 2014 Topics: Thermodynamics of energy systems; Power Loss; Peak Oil; Energy economics Problem Set #3 Solutions

    E-Print Network [OSTI]

    Kammen, Daniel M.

    ; Power Loss; Peak Oil; Energy economics Problem Set #3 Solutions Due October 9. Grade by October 16284) Fall 2014 Topics: Thermodynamics of energy systems; Power Loss; Peak Oil; Energy economics: Thermodynamics of energy systems; Power Loss; Peak Oil; Energy economics Problem Set #3 Solutions Due October 9

  13. The discrepancy between solar abundances and helioseismology

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    2005-01-07T23:59:59.000Z

    There have been recent downward revisions of the solar photospheric abundances of Oxygen and other heavy elements. These revised abundances along with OPAL opacities are not consistent with seismic constraints. In this work we show that the recently released OP opacity tables cannot resolve this discrepancy either. While the revision in opacities does not seem to resolve this conflict, an upward revision of Neon abundance in solar photosphere offers a possible solution to this problem.

  14. Biogeography-Based Optimization and the Solution of the Power Flow Problem

    E-Print Network [OSTI]

    Simon, Dan

    engineer Jules Carpentier [7]. A power utility may own power generating plants fueled by coal, natural gas. It is important to adjust the power output levels among the various generating plants in the system at any given, the Law of Conservation of Energy requires that the power generated by the plants must equal the power

  15. Fast and Accurate Fourier Series Solutions to Gravitational Lensing by A General Family of Two Power-Law Mass Distributions

    E-Print Network [OSTI]

    Kyu-Hyun Chae

    2001-12-10T23:59:59.000Z

    Fourier series solutions to the deflection and magnification by a family of three-dimensional cusped two power-law ellipsoidal mass distributions are presented. The cusped two power-law ellipsoidal mass distributions are characterized by inner and outer power-law radial indices and a break (or, transition) radius. The model family includes mass models mimicking Jaffe, Hernquist, and $\\eta$ models and dark matter halo profiles from numerical simulations. The Fourier series solutions for the cusped two power-law mass distributions are relatively simple, and allow a very fast calculation even for a chosen small fractional calculational error (e.g. $10^{-5}$). These results will be particularly useful for studying lensed systems which provide a number of accurate lensing constraints and for systematic analyses of large numbers of lenses. Subroutines employing these results for the two power-law model and the results by Chae, Khersonsky, & Turnshek for the generalized single power-law mass model are made publicly available.

  16. STRUCTURAL HEALTH MONITORING SOLUTIONS FOR POWER PLANTS Benoit Jouan, Jurgen Rudolph, Steffen Bergholz

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    but also in the context of conventional power plants and renewables such as wind power plants. Consequently of the fatigue analysis process: new design fatigue curves, consideration of environmental fatigue (EAF : Structural Health Monitoring, Fatigue Monitoring, Ageing Management, Power Plants, AREVA Fatigue Concept (AFC

  17. Planetary nebulae: abundances and abundance gradients

    E-Print Network [OSTI]

    W. J. Maciel

    1999-11-05T23:59:59.000Z

    In this work, a review is given of some recent results and problems involved in the determination of chemical abundances of galactic planetary nebulae, particularly regarding disk and bulge objects.

  18. Helioseismology and Solar Abundances

    E-Print Network [OSTI]

    Sarbani Basu; H. M. Antia

    2007-11-28T23:59:59.000Z

    Helioseismology has allowed us to study the structure of the Sun in unprecedented detail. One of the triumphs of the theory of stellar evolution was that helioseismic studies had shown that the structure of solar models is very similar to that of the Sun. However, this agreement has been spoiled by recent revisions of the solar heavy-element abundances. Heavy element abundances determine the opacity of the stellar material and hence, are an important input to stellar model calculations. The models with the new, low abundances do not satisfy helioseismic constraints. We review here how heavy-element abundances affect solar models, how these models are tested with helioseismology, and the impact of the new abundances on standard solar models. We also discuss the attempts made to improve the agreement of the low-abundance models with the Sun and discuss how helioseismology is being used to determine the solar heavy-element abundance. A review of current literature shows that attempts to improve agreement between solar models with low heavy-element abundances and seismic inference have been unsuccessful so far. The low-metallicity models that have the least disagreement with seismic data require changing all input physics to stellar models beyond their acceptable ranges. Seismic determinations of the solar heavy-element abundance yield results that are consistent with the older, higher values of the solar abundance, and hence, no major changes to the inputs to solar models are required to make higher-metallicity solar models consistent with helioseismic data.

  19. The Solar Argon Abundance

    E-Print Network [OSTI]

    Katharina Lodders

    2007-10-24T23:59:59.000Z

    The solar argon abundance cannot be directly derived by spectroscopic observations of the solar photosphere. The solar Ar abundance is evaluated from solar wind measurements, nucleosynthetic arguments, observations of B stars, HII regions, planetary nebulae, and noble gas abundances measured in Jupiter's atmosphere. These data lead to a recommended argon abundance of N(Ar) = 91,200(+/-)23,700 (on a scale where Si = 10^6 atoms). The recommended abundance for the solar photosphere (on a scale where log N(H) = 12) is A(Ar)photo = 6.50(+/-)0.10, and taking element settling into account, the solar system (protosolar) abundance is A(Ar)solsys = 6.57(+/-)0.10.

  20. Solutions of the stream power equation and application to the evolution of river longitudinal profiles

    E-Print Network [OSTI]

    Royden, Leigh H.

    Erosion by bedrock river channels is commonly modeled with the stream power equation. We present a two-part approach to solving this nonlinear equation analytically and explore the implications for evolving river profiles. ...

  1. The Primordial Helium Abundance

    E-Print Network [OSTI]

    Manuel Peimbert

    2008-11-18T23:59:59.000Z

    I present a brief review on the determination of the primordial helium abundance by unit mass, Yp. I discuss the importance of the primordial helium abundance in: (a) cosmology, (b) testing the standard big bang nucleosynthesis, (c) studying the physical conditions in H II regions, (d) providing the initial conditions for stellar evolution models, and (e) testing the galactic chemical evolution models.

  2. Solutions for Summer Electric Power Shortages: Demand Response andits Applications in Air Conditioning and Refrigerating Systems

    SciTech Connect (OSTI)

    Han, Junqiao; Piette, Mary Ann

    2007-11-30T23:59:59.000Z

    Demand response (DR) is an effective tool which resolves inconsistencies between electric power supply and demand. It further provides a reliable and credible resource that ensures stable and economical operation of the power grid. This paper introduces systematic definitions for DR and demand side management, along with operational differences between these two methods. A classification is provided for DR programs, and various DR strategies are provided for application in air conditioning and refrigerating systems. The reliability of DR is demonstrated through discussion of successful overseas examples. Finally, suggestions as to the implementation of demand response in China are provided.

  3. Case Study - Florida Power & Light - Smart Grid Solutions Strengthen Reliability and Services - July 2012.pdf

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China U.S. Department ofJuneWaste To Wisdom:EnergyJoshua DeLung WhatFlorida Power

  4. Innovative Phase Change Thermal Energy Storage Solution for Baseload Power Phase 1 Final Report

    SciTech Connect (OSTI)

    Qiu, Songgang

    2013-05-15T23:59:59.000Z

    The primary purpose of this project is to develop and validate an innovative, scalable phase change salt thermal energy storage (TES) system that can interface with Infinia’s family of free-piston Stirling engines (FPSE). This TES technology is also appropriate for Rankine and Brayton power converters. Solar TES systems based on latent heat of fusion rather than molten salt temperature differences, have many advantages that include up to an order of magnitude higher energy storage density, much higher temperature operation, and elimination of pumped loops for most of Infinia’s design options. DOE has funded four different concepts for solar phase change TES, including one other Infinia awarded project using heat pipes to transfer heat to and from the salt. The unique innovation in this project is an integrated TES/pool boiler heat transfer system that is the simplest approach identified to date and arguably has the best potential for minimizing the levelized cost of energy (LCOE). The Phase 1 objectives are to design, build and test a 1-hour TES proof-of-concept lab demonstrator integrated with an Infinia 3 kW Stirling engine, and to conduct a preliminary design of a 12-hour TES on-sun prototype.

  5. 8/25/07 11:53 PMNUCLEAR POWER:A Nuclear Solution to Climate Change? --Sailor et al. 288 (5469): 1177 --Science Page 1 of 6http://www.sciencemag.org/cgi/content/full/288/5469/1177

    E-Print Network [OSTI]

    Kammen, Daniel M.

    8/25/07 11:53 PMNUCLEAR POWER:A Nuclear Solution to Climate Change? -- Sailor et al. 288 (5469: Vol. 288. no. 5469, pp. 1177 - 1178 DOI: 10.1126/science.288.5469.1177 POLICY FORUM NUCLEAR POWER. , pp. 1177 - 1178 #12;8/25/07 11:53 PMNUCLEAR POWER:A Nuclear Solution to Climate Change? -- Sailor et

  6. New Solutions of the $2+1$ Dimensional Einstein Gravity Coupled to Maxwell Power type Non Linear Electric field with Dilaton field

    E-Print Network [OSTI]

    Masashi Kuniyasu

    2015-01-27T23:59:59.000Z

    New solutions are derived in the $2+1$ gravity which is coupled to $|{\\cal F}|^k$ type non-linear electric field in Maxwell Power theory with dilaton field. We obtain consistent solutions in general $k$ case. We also investigate the behavior of the metric function with the space-time singularity. Then, we found some black hole solutions when the space-time has a singular point at $r=0$. Addition, we derive the Brown-York mass when the space-time represents black hole.

  7. Islanding model for preventing wide-area blackouts and the issue of local solutions of the optimal power flow problem. 

    E-Print Network [OSTI]

    Bukhsh, Waqquas Ahmed

    2014-07-01T23:59:59.000Z

    Optimization plays a central role in the control and operation of electricity power networks. In this thesis we focus on two very important optimization problems in power systems. The first is the optimal power flow ...

  8. Elemental Abundances of Nearby Galaxies through High Signal-to-Noise XMM-Newton Observations of ULXs

    E-Print Network [OSTI]

    Lisa M. Winter; Richard F. Mushotzky; Christopher S. Reynolds

    2006-10-12T23:59:59.000Z

    (abridged) In this paper, we examined XMM Newton EPIC spectra of 14 ultra-luminous X-ray sources (ULXs)in addition to the XMM RGS spectra of two sources (Holmberg II X-1 and Holmberg IX X-1). We determined oxygen and iron abundances of the host galaxy's interstellar medium (ISM) using K-shell (O) and L-shell (Fe) X-ray photo-ionization edges towards these ULXs. We found that the oxygen abundances closely matched recent solar abundances for all of our sources, implying that ULXs live in similar local environments despite the wide range of galaxy host properties. Also, we compare the X-ray hydrogen column densities (n_H) for 8 ULX sources with column densities obtained from radio H I observations. The X-ray model n_H values are in good agreement with the H I n_H values, implying that the hydrogen absorption towards the ULXs is not local to the source (with the exception of the source M81 XMM1). In order to obtain the column density and abundance values, we fit the X-ray spectra of the ULXs with a combined power law and one of several accretion disk models. We tested the abundances obtained from the XSPEC models bbody, diskbb, grad, and diskpn along with a power law, finding that the abundances were independent of the thermal model used. We comment on the physical implications of these different model fits. We also note that very deep observations allow a breaking of the degeneracy noted by Stobbart et al. (2006) favoring a high mass solution for the absorbed grad + power law model.

  9. Constraining solar abundances using helioseismology

    E-Print Network [OSTI]

    Sarbani Basu; H. M. Antia

    2004-03-19T23:59:59.000Z

    Recent analyses of solar photospheric abundances suggest that the oxygen abundance in the solar atmosphere needs to be revised downwards. In this study we investigate the consequence of this revision on helioseismic analyses of the depth of the solar convection zone and the helium abundance in the solar envelope and find no significant effect. We also find that the revised abundances along with the current OPAL opacity tables are not consistent with seismic data. A significant upward revision of the opacity tables is required to make solar models with lower oxygen abundance consistent with seismic observations.

  10. Part of the Climate Change Problem . . . and the Solution? Chinese-Made Wind Power Technology and Opportunities for Dissemination

    E-Print Network [OSTI]

    Lewis, Joanna I.

    2005-01-01T23:59:59.000Z

    was  directly  tied  to  wind  turbine  cost.  Goldwind’s countries where  the cost of wind power technology had bringing  down  the  cost  of  wind?powered  electricity.  

  11. The Solar Heavy Element Abundances: I. Constraints from Stellar Interiors

    E-Print Network [OSTI]

    Franck Delahaye; Marc Pinsonneault

    2005-11-29T23:59:59.000Z

    The latest solar atmosphere models include non-LTE corrections and 3D hydrodynamic convection simulations. These models predict a significant reduction in the solar metal abundance, which leads to a serious conflict between helioseismic data and the predictions of solar interiors models. We demonstrate that the helioseismic constraints on the surface convection zone depth and helium abundance combined with stellar interiors models can be used to define the goodness of fit for a given chemical composition. After a detailed examination of the errors in the theoretical models we conclude that models constructed with the older solar abundances are consistent (seismic data. Models constructed with the proposed new low abundance scale are strongly disfavored, disagreeing at the 15 \\sigma level. We then use the sensitivity of the seismic properties to abundance changes to invert the problem and infer a seismic solar heavy element abundance mix with two components: meteoritic abundances, and the light metals CNONe. Seismic degeneracies between the best solutions for the elements arise for changes in the relative CNONe abundances and their effects are quantified. We obtain Fe/H=7.50+/-0.045+/-0.003(CNNe) and O/H=8.86+/-0.041+/-0.025(CNNe) for the relative CNNe in the GS98 mixture. The inferred solar oxygen abundance disagree with the abundance inferred from the 3D hydro models. Changes in the Ne abundance can mimic changes in O for the purposes of scalar constraints.Models constructed with low oxygen and high neon are inconsistent with the solar sound speed profile. The implications for the solar abundance scale are discussed.

  12. Determining solar abundances using helioseismology

    E-Print Network [OSTI]

    H. M. Antia; Sarbani Basu

    2006-02-28T23:59:59.000Z

    The recent downward revision of solar photospheric abundances of Oxygen and other heavy elements has resulted in serious discrepancies between solar models and solar structure as determined through helioseismology. In this work we investigate the possibility of determining the solar heavy-element abundance without reference to spectroscopy by using helioseismic data. Using the dimensionless sound-speed derivative in the solar convection zone, we find that the heavy element abundance, Z, of 0.0172 +/- 0.002, which is closer to the older, higher value of the abundances.

  13. Topology in QCD and the axion abundance

    E-Print Network [OSTI]

    Ryuichiro Kitano; Norikazu Yamada

    2015-06-01T23:59:59.000Z

    The temperature dependence of the topological susceptibility (chi_t) in QCD essentially determines the abundance of the QCD axion in the Universe, and is commonly estimated, based on the instanton picture, to be a certain negative power of temperature. While lattice QCD should be able to check the instanton picture in principle, the region of the temperature where lattice calculations of chi_t are reliable is rather limited in practice, because existing methods on the lattice will probably fail when chi_t decreases rapidly with temperatures. In this work, two exploratory studies are presented. First, to realize the limitation of temperature we perform lattice calculations of chi_t in the quenched approximation and find that it becomes difficult with a given resource when T > 2 T_c. A possible way out is proposed and some test calculations are given. The absolute value and the temperature dependence of chi_t in real QCD can be significantly different from that in the quenched approximation, and is not well established over a wide range of the temperature above its critical value. Motivated by this fact and precedent arguments which disagree with the conventional instanton picture, we estimate the axion abundance in an extreme case where chi_t decreases much faster than the conventional power-like function. We find a significant enhancement of the axion abundance in such a case.

  14. Primordial Li abundance and massive particles

    SciTech Connect (OSTI)

    Latin-Capital-Letter-Eth apo, H. [Department of Physics, Akdeniz University, TR-07058, Antalya (Turkey)

    2012-10-20T23:59:59.000Z

    The problem of the observed lithium abundance coming from the Big Bang Nucleosynthesis is as of yet unsolved. One of the proposed solutions is including relic massive particles into the Big Bang Nucleosynthesis. We investigated the effects of such particles on {sup 4}HeX{sup -}+{sup 2}H{yields}{sup 6}Li+X{sup -}, where the X{sup -} is the negatively charged massive particle. We demonstrate the dominance of long-range part of the potential on the cross-section.

  15. 4918 IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 28, NO. 4, NOVEMBER 2013 Towards Faster Solution of Large

    E-Print Network [OSTI]

    Vuik, Kees

    dictates the integrated management of power systems of continental scale. 2) Smartgrids: ICT technologies clusters (smartgrids), consisting of loads and local Manuscript received June 15, 2012; revised November 06

  16. A Short-Distance Integral-Balance Solution to a Strong Subdiffusion Equation: A Weak Power-Law Profile

    E-Print Network [OSTI]

    Jordan Hristov

    2010-12-12T23:59:59.000Z

    The work presents an integral solution of the time-fractional subdiffusion through a preliminary defined profile with unknown coefficients and the concept of penetration layer well known from the heat diffusion The profile satisfies the boundary conditions imposed at the boundary of the boundary layer in a weak form that allows its coefficients to be expressed through the boundary layer depth as unique parameter describing the profile. The technique is demonstrated by a solution of a time fractional subdiffusion equation in rectilinear 1-D conditions

  17. Hybrid Electric Vehicle Power Management Solutions Based on Isolated and Non-Isolated Configurations of MMCCC Converter

    SciTech Connect (OSTI)

    Khan, Faisal H [ORNL; Tolbert, Leon M [ORNL; Webb, William E [Oak Ridge National Laboratory (ORNL)

    2009-01-01T23:59:59.000Z

    This paper presents the various configurations of a multilevel modular capacitor-clamped converter (MMCCC), and it reveals many useful and new formations of the original MMCCC for transferring power in either an isolated or nonisolated manner. The various features of the original MMCCC circuit are best suited for a multibus system in future plug-in hybrid or fuel-cell-powered vehicles' drive train. The original MMCCC is capable of bidirectional power transfer using multilevel modular structure with capacitor-clamped topology. It has a nonisolated structure, and it offers very high efficiency even at partial loads. This circuit was modified to integrate single or multiple high-frequency transformers by using the intermediate voltage nodes of the converter. On the other hand, a special formation of the MMCCC can exhibit dc outputs offering limited isolation without using any isolation transformer. This modified version can produce a high conversion ratio from a limited number of components and has several useful applications in providing power to multiple low-voltage loads in a hybrid or electric automobile. This paper will investigate the origin of generating ac outputs from the MMCCC and shows how the transformer-free version can be modified to create limited isolation from the circuit. In addition, this paper will compare various modified forms of the MMCCC topology with existing dc-dc converter circuits from compactness and component utilization perspectives.

  18. Sandia Energy - SCADA Engineering Solutions

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

    Engineering Solutions Home Stationary Power Safety, Security & Resilience of Energy Infrastructure Grid Modernization Cyber Security for Electric Infrastructure National...

  19. Gd Transition Probabilities and Abundances

    E-Print Network [OSTI]

    E. A. Den Hartog; J. E. Lawler; C. Sneden; J. J. Cowan

    2006-09-18T23:59:59.000Z

    Radiative lifetimes, accurate to +/- 5%, have been measured for 49 even-parity and 14 odd-parity levels of Gd II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 611 lines of Gd II. This work is the largest-scale laboratory study to date of Gd II transition probabilities and the first using a high performance Fourier transform spectrometer. This improved data set has been used to determine a new solar photospheric Gd abundance, log epsilon = 1.11 +/- 0.03. Revised Gd abundances have also been derived for the r-process-rich metal-poor giant stars CS 22892-052, BD+17 3248, and HD 115444. The resulting Gd/Eu abundance ratios are in very good agreement with the solar-system r-process ratio. We have employed the increasingly accurate stellar abundance determinations, resulting in large part from the more precise laboratory atomic data, to predict directly the Solar System r-process elemental abundances for Gd, Sm, Ho and Nd. Our analysis of the stellar data suggests slightly higher recommended values for the r-process contribution and total Solar System values, consistent with the photospheric determinations, for the elements for Gd, Sm, and Ho.

  20. RECYCLABILITY CHALLENGES IN "ABUNDANT" MATERIAL-BASED TECHNOLOGIES Annick Anctila

    E-Print Network [OSTI]

    RECYCLABILITY CHALLENGES IN "ABUNDANT" MATERIAL-BASED TECHNOLOGIES Annick Anctila and Fthenakisa of photovoltaic installations grow, greatly displacing traditional power- generation infrastructures, recycling a take-back- or recycling-program ahead of time. Our work explores the potential for material recycling

  1. Sustainable Solutions Abundant in New Offices - News Feature | NREL

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposed Action Title: Sustainable

  2. In-pile measurements of the decay constants and relative abundances of delayed neutrons

    SciTech Connect (OSTI)

    Spriggs, G.D. (Los Alamos National Lab., NM (United States))

    1993-08-01T23:59:59.000Z

    An in-pile experimental technique to measure the decay constants and the relative abundances of the delayed neutron groups applicable for a given reactor system is presented. The method is based on a least-squares-fitting technique that simultaneously fits a series of transients produced by small reactivity perturbations to a reactor operating initially at delayed critical. The function that is least-squares fit is the analytic solution (written in terms of an arbitrary number of delayed neutron groups) as obtained by the point reactor model for the reactor response following a step change in reactivity. The application of the method does not require any knowledge of the size of the reactivity perturbations, and the method is independent of the detector efficiency. The results are based solely on the measurable quantities of relative power, time, and one measurable root of the Inhour equation.

  3. Hf Transition Probabilities and Abundances

    E-Print Network [OSTI]

    J. E. Lawler; E. A. Den Hartog; Z. E. Labby; C. Sneden; J. J. Cowan; I. I. Ivans

    2006-11-01T23:59:59.000Z

    Radiative lifetimes from laser-induced fluorescence measurements, accurate to about +/- 5 percent, are reported for 41 odd-parity levels of Hf II. The lifetimes are combined with branching fractions measured using Fourier transform spectrometry to determine transition probabilities for 150 lines of Hf II. Approximately half of these new transition probabilities overlap with recent independent measurements using a similar approach. The two sets of measurements are found to be in good agreement for measurements in common. Our new laboratory data are applied to refine the hafnium photospheric solar abundance and to determine hafnium abundances in 10 metal-poor giant stars with enhanced r-process abundances. For the Sun we derive log epsilon (Hf) = 0.88 +/- 0.08 from four lines; the uncertainty is dominated by the weakness of the lines and their blending by other spectral features. Within the uncertainties of our analysis, the r-process-rich stars possess constant Hf/La and Hf/Eu abundance ratios, log epsilon (Hf/La) = -0.13 +/- 0.02 (sigma = 0.06) and log epsilon (Hf/Eu) = +0.04 +/- 0.02 (sigma = 0.06). The observed average stellar abundance ratio of Hf/Eu and La/Eu is larger than previous estimates of the solar system r-process-only value, suggesting a somewhat larger contribution from the r-process to the production of Hf and La. The newly determined Hf values could be employed as part of the chronometer pair, Th/Hf, to determine radioactive stellar ages.

  4. The effects of He I 10830 on helium abundance determinations

    E-Print Network [OSTI]

    Aver, Erik; Skillman, Evan D

    2015-01-01T23:59:59.000Z

    Observations of helium and hydrogen emission lines from metal-poor extragalactic H II regions provide an independent method for determining the primordial helium abundance, Y_p. Traditionally, the emission lines employed are in the visible wavelength range, and the number of suitable lines is limited. Furthermore, when using these lines, large systematic uncertainties in helium abundance determinations arise due to the degeneracy of physical parameters, such as temperature and density. Recently, Izotov, Thuan, & Guseva (2014) have pioneered adding the He 10830 infrared emission line in helium abundance determinations. The strong electron density dependence of He 10830 makes it ideal for better constraining density, potentially breaking the degeneracy with temperature. We revisit our analysis of the dataset published by Izotov, Thuan, & Stasinska (2007) and incorporate the newly available observations of He 10830 by scaling them using the observed-to-theoretical Paschen-gamma ratio. The solutions are b...

  5. Ultracoatings: Enabling Energy and Power Solutions in High Contact Stress Environments through next-generation Nanocoatings Final Technical Report

    SciTech Connect (OSTI)

    Clifton B. Higdon III

    2012-03-20T23:59:59.000Z

    A review of current commercially available, industrial-grade, low friction coatings will show that interfacial contact pressures nearing 1GPa ({approx}150ksi) inherently limit surface engineering solutions like WC, TiN, TiAlN, and so forth. Extremely hard coatings, then, are often pursued as the principle path, although they too are not without significant limitations. A majority of these compounds are inherently brittle in nature or may not pair well with their mating substrate. In either case, their durability in high contact stress environments is compromised. In parallel to thin film coatings, many conventional surface treatments do not yield an interface hard enough to withstand extreme stresses under load. New research into advanced, nanocomposite materials like (Ti, Zr)B2 shows great promise. Bulk compacts of this compound have demonstrated an order of magnitude better wear resistance than current offerings, notably materials like tungsten carbide. At a laboratory level, the (Ti,Zr)B2 nanocomposite material exhibited abrasive and erosive wear resistance nearly ten times better than existing mixed-phase boride systems. In ASTM abrasion and erosion testing, these new compositions exhibit wear resistance superior to other known advanced materials such as RocTec 500 and 'Borazon' cubic boron nitride. Many significant challenges exist for mass production of (Ti, Zr)B2, one of which is the necessary processing technology that is capable of minimizing deleterious impurity phases. Secondly, this material's performance is derived from a synergistic effect of the two materials existing as a single phase structure. While the individual constituents of TiB2 and ZrB2 do yield improvements to wear resistance, their singular effects are not as significant. Lastly, deposition of this material on a commercial level requires thorough knowledge of nanocomposite boride solids; the benefits associated with these innovative new materials are just being realized. Advancing this technology, called Ultracoatings, through initial development, scale up, and commercialization to a variety of markets would represent a transformative leap to surface engineering. Several application spaces were considered for immediate implementation of the Ultracoatings technology, including, but not limited to, a drive shaft for an aerospace fuel pump, engine timing components, and dry solids pump hardware for an innovative coal gasifier. The primary focus of the program was to evaluate and screen the performance of the selected (Ti, Zr)B2 Ultracoatings composition for future development. This process included synthesis of the material for physical vapor deposition, sputtering trials and coating characterization, friction and wear testing on sample coupons, and functional hardware testing. The main project deliverables used to gage the project's adherence to its original objective were: Development of a coating/substrate pairing that exhibits wear rate of 0.1 mg/hour or lower at a 1GPa contact pressure, while achieving a maximum coating cost of $0.10/cm2. Demonstrate the aforementioned wear rate in both lubricated and starved lubrication conditions. Although the (Ti, Zr) B2 coating was not tailored for low friction performance, friction and wear evaluations of the material demonstrated a coefficient of sliding friction as low as 0.09. This suggests that varying the percentage of TiB2 present in the composite could enhance the materials performance in water-based lubricants. In the aerospace drive shaft application, functional hardware coated with (Ti, Zr)B2 survived a variety of abuse and long-range durability tests, with contact pressures exceeding 2 GPa. For engine timing components, further work is planned to evaluate the Ultracoatings technology in direct injection and diesel engine conditions. In the final identified application space the dry solids pump hardware, discussions continue on the application of the Ultracoatings technology for those specific components. Full implementation of the technology into the targeted markets equates to a U.S.-based en

  6. Element Abundances at High Redshifts

    E-Print Network [OSTI]

    Max Pettini

    1999-02-11T23:59:59.000Z

    I review measurements of element abundances in different components of the high redshift universe, including the Lyman alpha forest, damped Lyman alpha systems, and Lyman break galaxies. Although progress is being made in all three areas, recent work has also produced some surprises and shown that established ideas about the nature of the damped Lyman alpha systems in particular may be too simplistic. Overall, our knowledge of metal abundances at high z is still very sketchy. Most significantly, there seems to be an order of magnitude shortfall in the comoving density of metals which have been measured up to now compared with those produced by the star formation activity seen in Lyman break galaxies. At least some of the missing metals are likely to be in hot gas in galactic halos and proto-clusters.

  7. Sm Transition Probabilities and Abundances

    E-Print Network [OSTI]

    J. E. Lawler; E. A. Den Hartog; C. Sneden; J. J. Cowan

    2005-10-19T23:59:59.000Z

    Radiative lifetimes, accurate to +/- 5%, have been measured for 212 odd-parity levels of Sm II using laser-induced fluorescence. The lifetimes are combined with branching fractions measured using Fourier-transform spectrometry to determine transition probabilities for more than 900 lines of Sm II. This work is the largest-scale laboratory study to date of Sm II transition probabilities using modern methods. This improved data set has been used to determine a new solar photospheric Sm abundance, log epsilon = 1.00 +/- 0.03, from 26 lines. The spectra of three very metal-poor, neutron-capture-rich stars also have been analyzed, employing between 55 and 72 Sm II lines per star. The abundance ratios of Sm relative to other rare earth elements in these stars are in agreement, and are consistent with ratios expected from rapid neutron-capture nucleosynthesis (the r-process).

  8. r-Process Abundance Signatures

    E-Print Network [OSTI]

    J. J. Cowan; C. Sneden

    2002-12-05T23:59:59.000Z

    Abundance observations indicate the presence of rapid-neutron capture (i.e., r-process) elements in old Galactic halo and globular cluster stars. These observations demonstrate that the earliest generations of stars in the Galaxy, responsible for neutron-capture synthesis and the progenitors of the halo stars, were rapidly evolving. Abundance comparisons among large numbers of stars provide clues about the nature of neutron-capture element synthesis both during the earliest times and throughout the history of the Galaxy. In particular, these comparisons suggest differences in the way the heavier (including Ba and above) and lighter neutron capture elements are synthesized in nature. Understanding these differences will help to identify the astrophysical site (or sites) of and conditions in the r-process. The abundance comparisons also demonstrate a large star-to-star scatter in the neutron-capture/iron ratios at low metallicities- which disappears with increasing [Fe/H]- and suggests an early, chemically unmixed and inhomogeneous Galaxy. The very recent neutron-capture element observations indicate that the early phases of Galactic nucleosynthesis, and the associated chemical evolution, are quite complex, with the yields from different (progenitor) mass-range stars contributing to different chemical mixes. Stellar abundance comparisons suggest a change from the r-process to the slow neutron capture (i.e., s-) process at higher metallicities (and later times) in the Galaxy. Finally, the detection of thorium and uranium in halo and globular cluster stars offers a promising, independent age-dating technique that can put lower limits on the age of the Galaxy and thus the Universe.

  9. Electron Abundance in Protostellar Cores

    E-Print Network [OSTI]

    Paolo Padoan; Karen Willacy; William Langer; Mika Juvela

    2004-06-23T23:59:59.000Z

    The determination of the fractional electron abundance, Xe, in protostellar cores relies on observations of molecules, such as DCO+, H13CO+ and CO, and on chemical models to interpret their abundance. Studies of protostellar cores have revealed significant variations of Xe from core to core within a range 10^-8abundance from core to core as the combined effect of visual extinction and age variations. The range of electron abundances predicted by the models is relatively insenstive to density over 10^4 to 10^6 cm^{-3}.

  10. The oxygen abundance distribution in M101

    E-Print Network [OSTI]

    L. S. Pilyugin

    2001-05-07T23:59:59.000Z

    The well-observed spiral galaxy M101 was considered. The radial distributions of oxygen abundances determined in three different ways (with the classic Te - method, with the R23 - method, and with the P -- method) were compared. It was found that the parameters (the central oxygen abundance and the gradient) of the radial O/H(P) abundance distribution are close to those of the O/H(Te) abundance distribution. The parameters of the O/H(R23) abundance distribution differ significantly from those of the O/H(Te) abundance distribution: the central O/H(R23) oxygen abundance is higher by around 0.4dex and the gradient is steeper by a factor of around 1.5 as compared to those values in the O/H(Te) abundance distribution. The dispersion in O/H(P) abundance at fixed radius is rather small, around 0.08 dex, and is equal to that in O/H(Te) abundance. The dispersion in O/H(R23) abundance at fixed radius is appreciably larger, around 0.16 dex, compared to that in O/H(Te) abundance. It has been shown that the extra dispersion in O/H(R23) abundances is an artifact and reflects scatter in excitation parameter P at fixed radius.

  11. Abundance measurements in stellar environments

    SciTech Connect (OSTI)

    Leone, F. [Università di Catania, Dipartimento di Fisica e Astronomia, Sezione Astrofisica, Via S. Sofia 78, 95123 Catania (Italy)

    2014-05-09T23:59:59.000Z

    Most of what we know about stars, and systems of stars, is derived from the analysis of their electromagnetic radiation. This lesson is an attempt to describe to Physicists, without any Astrophysical background, the framework to understand the present status of abundance determination in stellar environments and its limit. These notes are dedicated to the recently passed, November 21, 2013, Prof. Dimitri Mihalas who spent his life confuting the 19th century positivist philosopher Auguste Comte who stated that we shall not at all be able to determine the chemical composition of stars.

  12. Surface abundances of ON stars

    E-Print Network [OSTI]

    Martins, F; Palacios, A; Howarth, I; Georgy, C; Walborn, N R; Bouret, J -C; Barba, R

    2015-01-01T23:59:59.000Z

    Massive stars burn hydrogen through the CNO cycle during most of their evolution. When mixing is efficient, or when mass transfer in binary systems happens, chemically processed material is observed at the surface of O and B stars. ON stars show stronger lines of nitrogen than morphologically normal counterparts. Whether this corresponds to the presence of material processed through the CNO cycle or not is not known. Our goal is to answer this question. We perform a spectroscopic analysis of a sample of ON stars with atmosphere models. We determine the fundamental parameters as well as the He, C, N, and O surface abundances. We also measure the projected rotational velocities. We compare the properties of the ON stars to those of normal O stars. We show that ON stars are usually helium-rich. Their CNO surface abundances are fully consistent with predictions of nucleosynthesis. ON stars are more chemically evolved and rotate - on average - faster than normal O stars. Evolutionary models including rotation cann...

  13. Abundance Ratios in Early-Type Galaxies

    E-Print Network [OSTI]

    Reynier Peletier

    1999-04-21T23:59:59.000Z

    Although evidence is accumulating that abundance ratios in galaxies are often non-solar, they are far from understood. I resume the current evidence for non-solar abundance ratios, supplementing the recent review by Worthey (1998) with some new results. It appears that the Mg/Fe abundance ratio only depends on the mass of the galaxy, not on the formation time-scale. For massive galaxies [Mg/Fe] > 0, while small galaxies show solar abundance ratios. Information about abundances of other element is scarce, but new evidence is given that [Ca/Fe] is solar, or slightly lower than solar, contrary to what is expected for an alpha-element.

  14. DETERMINING THE INITIAL HELIUM ABUNDANCE OF THE SUN

    SciTech Connect (OSTI)

    Serenelli, Aldo M. [Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching D-85471 (Germany); Basu, Sarbani, E-mail: aldos@mpa-garching.mpg.d [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

    2010-08-10T23:59:59.000Z

    We determine the dependence of the initial helium abundance and the present-day helium abundance in the convective envelope of solar models (Y {sub ini} and Y {sub surf}, respectively) on the parameters that are used to construct the models. We do so by using reference standard solar models (SSMs) to compute the power-law coefficients of the dependence of Y {sub ini} and Y {sub surf} on the input parameters. We use these dependencies to determine the correlation between Y {sub ini} and Y {sub surf} and use this correlation to eliminate uncertainties in Y {sub ini} from all solar model input parameters except the microscopic diffusion rate. We find an expression for Y {sub ini} that depends only on Y {sub surf} and the diffusion rate. By adopting the helioseismic determination of solar surface helium abundance, Y {sup surf} {sub sun} = 0.2485 {+-} 0.0035, and an uncertainty of 20% for the diffusion rate, we find that the initial solar helium abundance, Y {sup ini} {sub sun}, is 0.278 {+-} 0.006 independently of the reference SSMs (and particularly on the adopted solar abundances) used in the derivation of the correlation between Y {sub ini} and Y {sub surf}. When non-SSMs with extra mixing are used, then we derive Y {sup ini} {sub sun} = 0.273 {+-} 0.006. In both cases, the derived Y {sup ini} {sub sun} value is higher than that directly derived from solar model calibrations when the low-metallicity solar abundances (e.g., by Asplund et al.) are adopted in the models.

  15. Stellar abundances of beryllium and CUBES

    E-Print Network [OSTI]

    Smiljanic, R

    2014-01-01T23:59:59.000Z

    Stellar abundances of beryllium are useful in different areas of astrophysics, including studies of the Galactic chemical evolution, of stellar evolution, and of the formation of globular clusters. Determining Be abundances in stars is, however, a challenging endeavor. The two Be II resonance lines useful for abundance analyses are in the near UV, a region strongly affected by atmospheric extinction. CUBES is a new spectrograph planned for the VLT that will be more sensitive than current instruments in the near UV spectral region. It will allow the observation of fainter stars, expanding the number of targets where Be abundances can be determined. Here, a brief review of stellar abundances of Be is presented together with a discussion of science cases for CUBES. In particular, preliminary simulations of CUBES spectra are presented, highlighting its possible impact in investigations of Be abundances of extremely metal-poor stars and of stars in globular clusters.

  16. Topology in QCD and the axion abundance

    E-Print Network [OSTI]

    Kitano, Ryuichiro

    2015-01-01T23:59:59.000Z

    The temperature dependence of the topological susceptibility (chi_t) in QCD essentially determines the abundance of the QCD axion in the Universe, and is commonly estimated, based on the instanton picture, to be a certain negative power of temperature. While lattice QCD should be able to check the instanton picture in principle, the region of the temperature where lattice calculations of chi_t are reliable is rather limited in practice, because existing methods on the lattice will probably fail when chi_t decreases rapidly with temperatures. In this work, two exploratory studies are presented. First, to realize the limitation of temperature we perform lattice calculations of chi_t in the quenched approximation and find that it becomes difficult with a given resource when T > 2 T_c. A possible way out is proposed and some test calculations are given. The absolute value and the temperature dependence of chi_t in real QCD can be significantly different from that in the quenched approximation, and is not well est...

  17. Neutrino Physics and the Primordial Elemental Abundances

    E-Print Network [OSTI]

    Christian Y. Cardall; George M. Fuller

    1997-01-31T23:59:59.000Z

    Limits can be placed on nonstandard neutrino physics when big bang nucleosynthesis (BBN) calculations employing standard neutrino physics agree with the observationally inferred primordial abundances of deuterium (D), $^3$He, $^4$He, and $^7$Li. These constraints depend most sensitively on the abundances of D and $^4$He. New observational determinations of the primordial D and/or $^4$He abundances could force revisions in BBN constraints on nonstandard neutrino physics.

  18. The abundance of brown dwarfs

    E-Print Network [OSTI]

    James Binney

    1999-05-25T23:59:59.000Z

    The amount of mass contained in low-mass objects is investigated anew. Instead of using a mass-luminosity relation to convert a luminosity function to a mass function, I predict the mass-luminosity relation from assumed mass functions and the luminosity functions of Jahreiss & Wielen (1997) and Gould et al (1997). Comparison of the resulting mass-luminosity relations with data from binary stars constrains the permissible mass functions. If the mass function is assumed to be a power law, the best fitting slope lies either side of the critical slope, -2, below which the mass in low-mass objects is divergent, depending on the luminosity function adopted. If these power-law mass functions are truncated at 0.001Msun, the contribution to the local density of stars lies between 0.016 and 0.039 Msun pc^-3, in conformity with the density measured dynamically from Hipparcos stars. If the mass function is generalized from a power law to a low-order polynomial in log(M), the mass in stars with M<0.1Msun is either negligible or strongly divergent, depending on the order of the polynomial adopted.

  19. On the oxygen abundance in our Galaxy

    E-Print Network [OSTI]

    L. S. Pilyugin; F. Ferrini; R. V. Shkvarun

    2003-02-03T23:59:59.000Z

    The compilation of published spectra of Galactic HII regions with available diagnostic [OIII]4363 line has been carried out. Our list contains 71 individual measurements of 13 HII regions in the range of galactocentric distances from 6.6 to 14.8 kpc. The oxygen abundances in all the HII regions were recomputed in the same way, using the classic Te - method. The oxygen abundance at the solar galactocentric distance traced by those HII regions is in agreement with the oxygen abundance in the interstellar medium in the solar vicinity derived with high precision from the interstellar absorption lines towards stars. The derived radial oxygen abundance distribution was compared with that for HII regions from the Shaver et al. (1983) sample which is the basis of many models for the chemical evolution of our Galaxy. It was found that the original Shaver et al.'s oxygen abundances are overestimated by 0.2-0.3 dex. Oxygen abundances in HII regions from the Shaver et al. sample have been redetermined with the recently suggested P - method. The radial distribution of oxygen abundances from the Shaver et al. sample redetermined with the P - method is in agreement with our radial distribution of (O/H)_Te abundances.

  20. On the solar nickel and oxygen abundances

    E-Print Network [OSTI]

    Pat Scott; Martin Asplund; Nicolas Grevesse; A. Jacques Sauval

    2009-01-27T23:59:59.000Z

    Determinations of the solar oxygen content relying on the neutral forbidden transition at 630 nm depend upon the nickel abundance, due to a Ni I blend. Here we rederive the solar nickel abundance, using the same ab initio 3D hydrodynamic model of the solar photosphere employed in the recent revision of the abundances of C, N, O and other elements. Using 17 weak, unblended lines of Ni I together with the most accurate atomic and observational data available we find log epsilon_Ni = 6.17 +/- 0.02 (statistical) +/- 0.05 (systematic), a downwards shift of 0.06 to 0.08 dex relative to previous 1D-based abundances. We investigate the implications of the new nickel abundance for studies of the solar oxygen abundance based on the [O I] 630 nm line in the quiet Sun. Furthermore, we demonstrate that the oxygen abundance implied by the recent sunspot spectropolarimetric study of Centeno & Socas-Navarro needs to be revised downwards from log epsilon_O = 8.86 +/- 0.07 to 8.71 +/- 0.10. This revision is based on the new nickel abundance, application of the best available gf-value for the 630 nm forbidden oxygen line, and a more transparent treatment of CO formation. Determinations of the solar oxygen content relying on forbidden lines now appear to converge around log epsilon_O = 8.7.

  1. Abundant Biofuels | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDITCaliforniaWeifangwiki HomeASN Power ProjectsAbraham Hot

  2. Helioseismological Implications of Recent Solar Abundance Determinations

    E-Print Network [OSTI]

    John N. Bahcall; Sarbani Basu; Marc Pinsonneault; Aldo M. Serenelli

    2004-09-26T23:59:59.000Z

    We show that standard solar models are in good agreement with the helioseismologically determined sound speed and density as a function of solar radius, the depth of the convective zone, and the surface helium abundance, as long as those models do not incorporate the most recent heavy element abundance determinations. However, sophisticated new analyses of the solar atmosphere infer lower abundances of the lighter metals (like C, N, O, Ne, and Ar) than the previously widely used surface abundances. We show that solar models that include the lower heavy element abundances disagree with the solar profiles of sound speed and density as well as the depth of the convective zone and the helium abundance. The disagreements for models with the new abundances range from factors of several to many times the quoted uncertainties in the helioseismological measurements. The disagreements are at temperatures below what is required for solar interior fusion reactions and therefore do not significantly affect solar neutrino emission. If errors in thecalculated OPAL opacities are solely responsible for the disagreements, then the corrections in the opacity must extend from 2 times 10^6 K (R = 0.7R_Sun)to 5 times 10^6 K (R = 0.4 R_Sun), with opacity increases of order 10%.

  3. On the solar abundance of indium

    E-Print Network [OSTI]

    N. Vitas; I. Vince; M. Lugaro; O. Andriyenko; M. Gosic; R. J. Rutten

    2007-11-14T23:59:59.000Z

    The generally adopted value for the solar abundance of indium is over six times higher than the meteoritic value. We address this discrepancy through numerical synthesis of the 451.13 nm line on which all indium abundance studies are based, both for the quiet-sun and the sunspot umbra spectrum, employing standard atmosphere models and accounting for hyperfine structure and Zeeman splitting in detail. The results, as well as a re-appraisal of indium nucleosynthesis, suggest that the solar indium abundance is close to the meteoritic value, and that some unidentified ion line causes the 451.13 nm feature in the quiet-sun spectrum.

  4. THE RAVE CATALOG OF STELLAR ELEMENTAL ABUNDANCES: FIRST DATA RELEASE

    SciTech Connect (OSTI)

    Boeche, C.; Williams, M.; De Jong, R. S.; Steinmetz, M. [Leibniz-Institut fuer Astrophysik Potsdam (AIP), D-14482 Potsdam (Germany); Siebert, A.; Bienayme, O. [Observatoire Astronomique de Strasbourg, Universite de Strasbourg, CNRS, UMR 7550, F-67000 Strasbourg (France); Fulbright, J. P.; Ruchti, G. R. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Bland-Hawthorn, J. [Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006 (Australia); Campbell, R. [Department of Physics and Astronomy, Western Kentucky University, Bowling Green, KY (United States); Freeman, K. C. [Research School of Astronomy and Astrophysics, Australia National University, Weston Creek, Canberra ACT 2611 (Australia); Gibson, B. K. [Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Gilmore, G. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Grebel, E. K. [Astronomisches Rechen-Institut, Zentrum fuer Astronomie der Universitaet Heidelberg, D-69120 Heidelberg (Germany); Helmi, A. [Kapteyn Astronomical Institute, University of Groningen, 9700 AV Groningen (Netherlands); Munari, U. [INAF Osservatorio Astronomico di Padova, Asiago I-36012 (Italy); Navarro, J. F. [Department of Physics and Astronomy, University of Victoria, Victoria BC V8W 3P6 (Canada); Parker, Q. A.; Reid, W. [Department of Physics and Astronomy, Faculty of Sciences, Macquarie University, Sydney, NSW 2109 (Australia); Seabroke, G. M. [Mullard Space Science Laboratory, University College London, Holmbury, St. Mary RH5 6NT (United Kingdom); and others

    2011-12-15T23:59:59.000Z

    We present chemical elemental abundances for 36,561 stars observed by the RAdial Velocity Experiment (RAVE), an ambitious spectroscopic survey of our Galaxy at Galactic latitudes |b| > 25 Degree-Sign and with magnitudes in the range 9 power R {approx} 7500. This first data release of the RAVE chemical catalog is complementary to the third RAVE data release of radial velocities and stellar parameters, and it contains chemical abundances for the elements Mg, Al, Si, Ca, Ti, Fe, and Ni, with a mean error of {approx}0.2 dex, as judged from accuracy tests performed on synthetic and real spectra. Abundances are estimated through a dedicated processing pipeline in which the curve of growth of individual lines is obtained from a library of absorption line equivalent widths to construct a model spectrum that is then matched to the observed spectrum via a {chi}{sup 2} minimization technique. We plan to extend this pipeline to include estimates for other elements, such as oxygen and sulfur, in future data releases.

  5. The oxygen abundance deficiency in irregular galaxies

    E-Print Network [OSTI]

    L. S. Pilyugin; F. Ferrini

    2000-01-05T23:59:59.000Z

    The observed oxygen abundances in a number of irregular galaxies have been compared with predictions of the closed-box model of chemical and photometric evolution of galaxies. Oxygen is found to be deficient with respect to the predicted abundances. This is an indicator in favor of loss of heavy elements via galactic winds or/and of infall of low--abundance gas onto the galaxy. The oxygen abundance deficiency observed within the optical edge of a galaxy cannot be explained by mixing with the gas envelope observed outside the optical limit. We confirm the widespread idea that a significant part of the heavy elements is ejected by irregular galaxies in the intergalactic medium.

  6. Beryllium abundances in metal-poor stars

    E-Print Network [OSTI]

    K. F. Tan; J. R. Shi; G. Zhao

    2008-10-15T23:59:59.000Z

    We have determined beryllium abundances for 25 metal-poor stars based on the high resolution and high signal-to-noise ratio spectra from the VLT/UVES database. Our results confirm that Be abundances increase with Fe, supporting the global enrichment of Be in the Galaxy. Oxygen abundances based on [O I] forbidden line implies a linear relation with a slope close to one for the Be vs. O trend, which indicates that Be is probably produced in a primary process. Some strong evidences are found for the intrinsic dispersion of Be abundances at a given metallicity. The deviation of HD132475 and HD126681 from the general Be vs. Fe and Be vs. O trend favours the predictions of the superbubble model, though the possibility that such dispersion originates from the inhomogeneous enrichment in Fe and O of the protogalactic gas cannot be excluded.

  7. Oxygen abundance of open cluster dwarfs

    E-Print Network [OSTI]

    Z. -X. Shen; X. -W. Liu; H. -W. Zhang; B. Jones; D. N. C. Lin

    2007-03-30T23:59:59.000Z

    We present oxygen abundances of dwarfs in the young open cluster IC 4665 deduced from the OI $\\lambda$7774 triplet lines and of dwarfs in the open cluster Pleiades derived from the [OI] $\\lambda$6300 forbidden line. Stellar parameters and oxygen abundances were derived using the spectroscopic synthesis tool SME (Spectroscopy Made Easy). We find a dramatic increase in the upper boundary of the OI triplet abundances with decreasing temperature in the dwarfs of IC 4665, consistent with the trend found by Schuler et al. in the open clusters Pleiades and M 34, and to a less extent in the cool dwarfs of Hyades (Schuler et al. 2006a) and UMa (King & Schuler 2005). By contrast, oxygen abundances derived from the [OI] $\\lambda$6300 forbidden line for stars in Pleiades and Hyades (Schuler et al. 2006b) are constant within the errors. Possible mechanisms that may lead a varying oxygen triplet line abundance are examined, including systematic errors in the stellar parameter determinations, the NLTE effects, surface activities and granulation. The age-related effects stellar surface activities (especially the chromospheric activities) are suggested by our analysis to blame for the large spreads of oxygen triplet line abundances.

  8. Element abundances in solar energetic particles: two physical processes, two abundance patterns

    E-Print Network [OSTI]

    Reames, Donald V

    2015-01-01T23:59:59.000Z

    Abundances of elements comprising solar energetic particles (SEPs) come with two very different patterns. Historically called "impulsive" and "gradual" events, they have been studied for 40 years, 20 years by the Wind spacecraft. Gradual SEP events measure coronal abundances. They are produced when shock waves, driven by coronal mass ejections (CMEs), accelerate the ambient coronal plasma; we discuss the average abundances of 21 elements that differ from corresponding solar photospheric abundances by a well-known dependence on the first ionization potential (FIP) of the element. The smaller impulsive ("3He-rich") SEP events are associated with magnetic reconnection involving open field lines from solar flares or jets that also eject plasma to produce accompanying CMEs. These events produce striking heavy-element abundance enhancements, relative to coronal abundances, by an average factor of 3 at Ne, 9 at Fe, and 900 for elements with 76 0.1 are even more strongly associated with narrow, slow CMEs, cooler coro...

  9. Modeling Generator Power Plant Portfolios and Pollution Taxes in

    E-Print Network [OSTI]

    Nagurney, Anna

    Modeling Generator Power Plant Portfolios and Pollution Taxes in Electric Power Supply Chain-term solution (e.g.,are long-term solution (e.g., solar power and wind power (solar power and wind power Heavy user of fossil fuels:Heavy user of fossil fuels: Electric power industryElectric power industry

  10. Dual spatial maps of transcript and protein abundance in the...

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

    Dual spatial maps of transcript and protein abundance in the mouse brain. Dual spatial maps of transcript and protein abundance in the mouse brain. Abstract: Integrating...

  11. Mapping protein abundance patterns in the brain using voxelation...

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

    protein abundance patterns in the brain using voxelation combined with liquid chromatography and mass spectrometry. Mapping protein abundance patterns in the brain using voxelation...

  12. Topological Analysis of Protein Co-Abundance Networks Identifies...

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

    Topological Analysis of Protein Co-Abundance Networks Identifies Novel Host Targets Important for HCV Infection and Pathogenesis Topological Analysis of Protein Co-Abundance...

  13. abundance life history: Topics by E-print Network

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

    of ectoparasite community and abundance across life history stages of avian host Environmental Sciences and Ecology Websites Summary: and abundance are often associated with the...

  14. The Political Economy of Wind Power in China

    E-Print Network [OSTI]

    Swanson, Ryan Landon

    2011-01-01T23:59:59.000Z

    solar panels are too expensive to install domestically, China‘China,? as Chinese wind resources are abundant and wind power is cheaper than solar

  15. Stochastic chemical enrichment in metal-poor systems II. Abundance ratios and scatter

    E-Print Network [OSTI]

    T. Karlsson; B. Gustafsson

    2005-04-27T23:59:59.000Z

    A stochastic model of the chemical enrichment of metal-poor systems by core-collapse supernovae is used to study the scatter in stellar abundance ratios. The resulting scatter in abundance ratios, e.g. as functions of the overall metallicity, is demonstrated to be crucially dependent on the as yet uncertain supernovae yields. The observed abundance ratios and their scatters therefore have diagnostic power as regards the yields. The relatively small star-to-star scatter observed in many chemical abundance ratios, e.g. by Cayrel et al. (2004) for stars down to [Fe/H] = -4, is tentatively explained by the averaging of a large number of contributing supernovae and by the cosmic selection effects favoring contributions from supernovae in a certain mass range for the most metal-poor stars. The scatter in observed abundances of alpha-elements is understood in terms of observational errors only, while additional spread in yields or sites of nucleosynthesis may affect the odd-even elements Na and Al. For the iron-group elements we find systematically too high predicted Cr/Fe and Cr/Mg ratios, as well as differences between the different sets of yields, both in terms of predicted abundance ratios and scatter. The semi-empirical yields recently suggested by Francois et al. (2004) are found to lead to scatter in abundance ratios significantly greater than observed, when applied in the inhomogeneous models. "Spurs", very narrow sequences in abundance-ratio diagrams, may disclose a single-supernova origin of the elements of the stars on the sequence. Verification of the existence of such features, called single supernova sequences (SSSs), is challenging. This will require samples of several hundred stars with abundance ratios observed to accuracies of 0.05 dex or better.

  16. Abundances of massive stars: some recent developments

    E-Print Network [OSTI]

    T. Morel

    2008-11-25T23:59:59.000Z

    Thanks to their usefulness in various fields of astrophysics (e.g. mixing processes in stars, chemical evolution of galaxies), the last few years have witnessed a large increase in the amount of abundance data for early-type stars. Two intriguing results emerging since the last reviews on this topic will be discussed: (a) nearby OB stars exhibit metal abundances generally lower than the solar/meteoritic estimates; (b) evolutionary models of single objects including rotation are largely unsuccessful in explaining the CNO properties of stars in the Galaxy and in the Magellanic clouds.

  17. Power Factor Reactive Power

    E-Print Network [OSTI]

    motor power: 117.7 V x 5.1 A = 600 W? = 0.6 kW? NOT the power measured by meter #12;Page 9 PSERC: displacement power factor: angle between voltage and current = 0 degrees pf = cos(0 degrees) = 1.0 true powerPage 1 PSERC Power Factor and Reactive Power Ward Jewell Wichita State University Power Systems

  18. Offshore Renewable Energy Solutions

    E-Print Network [OSTI]

    and sustainable energy supply. The UK is uniquely placed to harness its natural resources ­ wind, wave and tidal power ­ to meet its target of achieving 15% of energy consumption from renewable sources by 2020. CefasOffshore Renewable Energy Solutions #12;Cefas: meeting complex requirements The Centre

  19. Inferring Ecological Networks From Species Abundance Data

    E-Print Network [OSTI]

    Edinburgh, University of

    (LASSO), Sparse Bayesian Regression (SBR), Graphical Gaussian Models (GGMs) and Bayesian Networks (BNs to thank Marco Grzegorczyk for the answering my question about Bayesian networks and the MCMC methodsInferring Ecological Networks From Species Abundance Data Frank Dondelinger Master of Science

  20. Discovery of interstellar ketenyl (HCCO), a surprisingly abundant radical

    E-Print Network [OSTI]

    Agundez, Marcelino; Guelin, Michel

    2015-01-01T23:59:59.000Z

    We have conducted radioastronomical observations of 9 dark clouds with the IRAM 30m telescope. We present the first identification in space of the ketenyl radical (HCCO) toward the starless core Lupus-1A and the molecular cloud L483, and the detection of the related molecules ketene (H2CCO) and acetaldehyde (CH3CHO) in these two sources and 3 additional dark clouds. We also report the detection of the formyl radical (HCO) in the 9 targeted sources and of propylene (CH2CHCH3) in 4 of the observed sources, which extends significantly the number of dark clouds where these molecules are known to be present. We derive a beam-averaged column density of HCCO of 5e11 cm-2 in both Lupus-1A and L483, which means that the ketenyl radical is just 10 times less abundant than ketene in these sources. The non-negligible abundance of HCCO found implies that there must be a powerful formation mechanism able to counterbalance the efficient destruction of this radical through reactions with neutral atoms. The column densities d...

  1. Power processing and active protection for photovoltaic energy extraction

    E-Print Network [OSTI]

    Chan, Arthur Hsu Chen

    2015-01-01T23:59:59.000Z

    Solar photovoltaic power generation is a promising clean and renewable energy technology that can draw upon the planet's most abundant power source - the sun. However, relatively high levelized cost of energy (LCOE), the ...

  2. The Isotopic Abundances of Magnesium in Stars

    E-Print Network [OSTI]

    Pamela Gay; David L. Lambert

    1999-11-11T23:59:59.000Z

    Isotopic abundance ratios 24^Mg:25^Mg:26^Mg are derived for 20 stars from high- resolution spectra of the MgH A-X 0-0 band at 5140AA. With the exception of the weak g-band giant HR 1299, the stars are dwarfs that sample the metallicity range -1.8 < [Fe/H] <0.0. The abundance of 25^Mg amd 26^Mg relative to the dominant isotope 24^Mg decreases with decreasing [Fe/H] in fair accord with predictions from a recent model of galactic chemical evolution in which the Mg isotopes are synthesised by massive stars. Several stars appear especially enriched in the heavier Mg isotopes suggesting contamination by material from the envelopes of intermediate-mass AGB stars.

  3. Fully Solution-Processed Copper Chalcopyrite Thin Film Solar Cells: Materials Chemistry, Processing, and Device Physics

    E-Print Network [OSTI]

    Chung, Choong-Heui

    2012-01-01T23:59:59.000Z

    films. Photovoltaic devices with power conversion efficiencyhigh efficiency fully solution-deposited CISS photovoltaic

  4. Relative Abundance Measurements in Plumes and Interplumes

    E-Print Network [OSTI]

    Guennou, Chloé; Savin, Daniel Wolf

    2015-01-01T23:59:59.000Z

    We present measurements of relative elemental abundances in plumes and interplumes. Plumes are bright, narrow structures in coronal holes that extend along open magnetic field lines far out into the corona. Previous work has found that in some coronal structures the abundances of elements with a low first ionization potential (FIP) 10 eV). We have used EIS spectroscopic observations made on 2007 March 13 and 14 over an ~24 hour period to characterize abundance variations in plumes and interplumes. To assess their elemental composition, we have used a differential emission measure (DEM) analysis, which accounts for the thermal structure of the observed plasma. We have used lines from ions of iron, silicon, and sulfur. From these we have estimated the ratio of the iron and silicon FIP bias relative to that for sulfur. From the results, we have created FIP-bias-ratio maps. We find that the FIP-bias ratio is sometimes higher in plumes than in interplumes and that this enhancement can be time dependent. These res...

  5. Options for Affordable Fission Surface Power Systems

    SciTech Connect (OSTI)

    Houts, Mike; Gaddis, Steve; Porter, Ron; Van Dyke, Melissa; Martin, Jim; Godfroy, Tom; Bragg-Sitton, Shannon; Garber, Anne; Pearson, Boise [NASA Marshall Space Flight Center, VP31, MSFC, AL 35812 (United States)

    2006-07-01T23:59:59.000Z

    Fission surface power systems could provide abundant power anywhere on the surface of the moon or Mars. Locations could include permanently shaded regions on the moon and high latitudes on Mars. To be fully utilized, however, fission surface power systems must be safe, have adequate performance, and be affordable. This paper discusses options for the design and development of such systems. (authors)

  6. CHAOS I: Direct Chemical Abundances for HII Regions in NGC 628

    E-Print Network [OSTI]

    Berg, Danielle A; Skillman, Evan D; Pogge, Richard W; Moustakas, John; Groh-Johnson, Mara

    2015-01-01T23:59:59.000Z

    The CHemical Abundances of Spirals (CHAOS) project leverages the combined power of the Large Binocular Telescope (LBT) with the broad spectral range and sensitivity of the Multi Object Double Spectrograph (MODS) to measure "direct" abundances in large samples of HII regions in spiral galaxies. We present LBT MODS observations of 62 HII regions in the nearby NGC628. We measure one or more auroral lines ([OIII] 4363, [NII] 5755, [SIII] 6312, or [OII] 7320,7330) in a large number of HII regions (40). Comparing derived temperatures from multiple auroral line measurements, we find: a strong correlation between temperatures based on [SIII] and [NII]; and large discrepancies for some temperatures based on [OII] and [OIII]. These trends are consistent with other observations in the literature, yet, given the widespread use and acceptance of [OIII] as a temperature determinant, the magnitude of the T[OIII] discrepancies still came as a surprise. Based on these results, we conduct a uniform abundance analysis using the...

  7. abundance depth distribution: Topics by E-print Network

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

    12: 488-501 I N T R O DU C T I O N The species abundance distribution (SAD Enquist, Brian Joseph 4 Fauna, Distribution, Habitat Preference and Abundance CiteSeer Summary:...

  8. abundance distribution composition: Topics by E-print Network

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

    12: 488-501 I N T R O DU C T I O N The species abundance distribution (SAD Enquist, Brian Joseph 6 Fauna, Distribution, Habitat Preference and Abundance CiteSeer Summary:...

  9. abundance distribution results: Topics by E-print Network

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

    12: 488-501 I N T R O DU C T I O N The species abundance distribution (SAD Enquist, Brian Joseph 4 Fauna, Distribution, Habitat Preference and Abundance CiteSeer Summary:...

  10. Oxygen abundances in planet-harbouring stars. Comparison of different abundance indicators

    E-Print Network [OSTI]

    A. Ecuvillon; G. Israelian; N. C. Santos; N. G. Shchukina; M. Mayor; R. Rebolo

    2005-09-13T23:59:59.000Z

    We present a detailed and uniform study of oxygen abundances in 155 solar type stars, 96 of which are planet hosts and 59 of which form part of a volume-limited comparison sample with no known planets. EW measurements were carried out for the [O I] 6300 \\AA line and the O I triplet, and spectral synthesis was performed for several OH lines. NLTE corrections were calculated and applied to the LTE abundance results derived from the O I 7771-5 \\AA\\ triplet. Abundances from [O I], the O I triplet and near-UV OH were obtained in 103, 87 and 77 dwarfs, respectively. We present the first detailed and uniform comparison of these three oxygen indicators in a large sample of solar-type stars. There is good agreement between the [O/H] ratios from forbidden and OH lines, while the NLTE triplet shows a systematically lower abundance. We found that discrepancies between OH, [O I] and the O I triplet do not exceed 0.2 dex in most cases. We have studied abundance trends in planet host and comparison sample stars, and no obvious anomalies related to the presence of planets have been detected. All three indicators show that, on average, [O/Fe] decreases with [Fe/H] in the metallicity range -0.8oxygen overabundance of 0.1-0.2dex with respect to the comparison sample.

  11. Cosmological solutions to the Lithium problem: Big-bang nucleosynthesis with photon cooling, $X$-particle decay and a primordial magnetic field

    E-Print Network [OSTI]

    Dai G. Yamazaki; Motohiko Kusakabe; Toshitaka Kajino; Grant. J. Mathews; Myung-Ki Cheoun

    2014-06-30T23:59:59.000Z

    The $^7$Li abundance calculated in BBN with the baryon-to-photon ratio fixed from fits to the CMB power spectrum is inconsistent with the observed lithium abundances on the surface of metal-poor halo stars. Previous cosmological solutions proposed to resolve this $^7$Li problem include photon cooling (possibly via the Bose-Einstein condensation of a scalar particle) or the decay of a long-lived $X-$particle (possibly the next-to-lightest supersymmetric particle). In this paper we reanalyze these solutions, both separately and in concert. We also introduce the possibility of a primordial magnetic field (PMF) into these models. We constrain the $X-$particles and the PMF parameters by the observed light element abundances using a likelihood analysis to show that the inclusion of all three possibilities leads to an optimum solution to the lithium problem. We deduce allowed ranges for the $X-$particle parameters and energy density in the PMF that can solve $^7$Li problem.

  12. Lithium abundances in exoplanet-hosts stars

    E-Print Network [OSTI]

    M. Castro; S. Vauclair; O. Richard; N. C. Santos

    2008-03-20T23:59:59.000Z

    Exoplanet-host stars (EHS) are known to present surface chemical abundances different from those of stars without any detected planet (NEHS). EHS are, on the average, overmetallic compared to the Sun. The observations also show that, for cool stars, lithium is more depleted in EHS than in NEHS. The overmetallicity of EHS may be studied in the framework of two different scenarii. We have computed main sequence stellar models with various masses, metallicities and accretion rates. The results show different profiles for the lithium destruction according to the scenario. We compare these results to the spectroscopic observations of lithium.

  13. SAFS-UW-1001 Abundance of Adult Hatchery and Wild

    E-Print Network [OSTI]

    Washington at Seattle, University of

    SAFS-UW-1001 July 2010 Abundance of Adult Hatchery and Wild Salmon by Region of the North Pacific Moore Foundation #12;Hatchery and Wild Salmon Abundance Page ii TABLE OF CONTENTS Page Introduction .............................................................................................................................. 1 Approaches to estimating wild salmon spawner abundances......................................... 1

  14. s- and r-process element abundances in the CMD of 47 Tucanae using the Robert Stobie Spectrograph on SALT

    E-Print Network [OSTI]

    C. C. Worley; P. L. Cottrell; E. C. Wylie de Boer

    2008-02-04T23:59:59.000Z

    A recent study by Wylie et al 2006 has revealed that s-process element abundances are enhanced relative to iron in both red giant branch and asymptotic giant branch stars of 47 Tucanae. A more detailed investigation into s-process element abundances throughout the colour-magnitude diagram of 47 Tucanae is vital in order to determine whether the observed enhancements are intrinsic to the cluster. This paper explores this possibility through observational and theoretical means. The visibility of s- and r-process element lines in synthetic spectra of giant and dwarf stars throughout the colour magnitude diagram of 47 Tucanae has been explored. It was determined that a resolving power of 10 000 was sufficient to observe s-process element abundance variations in globular cluster giant branch stars. These synthetic results were compared with the spectra of eleven 47 Tucanae giant branch stars observed during the performance verification of the Robert Stobie Spectrograph on the Southern African Large Telescope. Three s-process elements, Zr, Ba, Nd, and one r-process element, Eu, were investigated. No abundance variations were found such that [X/Fe] = 0.0 +/- 0.5 dex. It was concluded that this resolving power, R ~ 5000, was not sufficient to obtain exact abundances but upper limits on the s-process element abundances could be determined.

  15. Power Plant Power Plant

    E-Print Network [OSTI]

    Tingley, Joseph V.

    Basin Center for Geothermal Energy at University of Nevada, Reno (UNR) 2 Nevada Geodetic LaboratoryStillwater Power Plant Wabuska Power Plant Casa Diablo Power Plant Glass Mountain Geothermal Area Lassen Geothermal Area Coso Hot Springs Power Plants Lake City Geothermal Area Thermo Geothermal Area

  16. Element Abundances through the Cosmic Ages

    E-Print Network [OSTI]

    Max Pettini

    2003-03-12T23:59:59.000Z

    The horizon for studies of element abundances has expanded dramatically in the last ten years. Once the domain of astronomers concerned chiefly with stars and nearby galaxies, this field has now become a key component of observational cosmology, as technological advances have made it possible to measure the abundances of several chemical elements in a variety of environments at redshifts up to z = 4, when the universe was in its infancy. In this series of lectures I summarise current knowledge on the chemical make-up of distant galaxies observed directly in their starlight, and of interstellar and intergalactic gas seen in absorption against the spectra of bright background sources. The picture which is emerging is one where the universe at z = 3 already included many of the constituents of today's galaxies-even at these early times we see evidence for Population I and II stars, while the `smoking gun' for Population III objects may be hidden in the chemical composition of the lowest density regions of the intergalactic medium, yet to be deciphered.

  17. Beryllium abundances in stars hosting giant planets

    E-Print Network [OSTI]

    N. C. Santos; R. J. Garcia Lopez; G. Israelian; M. Mayor; R. Rebolo; A. Garcia-Gil; M. R. Perez de Taoro; S. Randich

    2002-02-25T23:59:59.000Z

    We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated stars. Predictions from current models are compared with the derived abundances and suggestions are provided to explain the observed inconsistencies. We show that while still not clear, the results suggest that theoretical models may have to be revised for stars with Teff<5500K. On the other hand, a comparison between planet host and non-planet host stars shows no clear difference between both populations. Although preliminary, this result favors a ``primordial'' origin for the metallicity ``excess'' observed for the planetary host stars. Under this assumption, i.e. that there would be no differences between stars with and without giant planets, the light element depletion pattern of our sample of stars may also be used to further investigate and constraint Li and Be depletion mechanisms.

  18. Oxygen Abundance Measurements of SHIELD Galaxies

    E-Print Network [OSTI]

    Haurberg, Nathalie C; Cannon, John M; Marshall, Melissa V

    2015-01-01T23:59:59.000Z

    We have derived oxygen abundances for 8 galaxies from the Survey of HI in Extremely Low-mass Dwarfs (SHIELD). The SHIELD survey is an ongoing study of very low-mass galaxies, with M$_{\\rm HI}$ between 10$^{6.5}$ and 10$^{7.5}$ M$_{\\odot}$, that were detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey. H$\\alpha$ images from the WIYN 3.5m telescope show that these 8 SHIELD galaxies each possess one or two active star-forming regions which were targeted with long-slit spectral observations using the Mayall 4m telescope at KPNO. We obtained a direct measurement of the electron temperature by detection of the weak [O III] $\\lambda$4363 line in 2 of the HII regions. Oxygen abundances for the other HII regions were estimated using a strong-line method. When the SHIELD galaxies are plotted on a B-band luminosity-metallicity diagram they appear to suggest a slightly shallower slope to the relationship than normally seen. However, that offset is systematically reduced when the near-infrared luminosity is used ins...

  19. The Solar Heavy Element Abundances: I. Constraints from Stellar Interiors

    E-Print Network [OSTI]

    Delahaye, F; Delahaye, Franck; Pinsonneault, Marc

    2005-01-01T23:59:59.000Z

    The latest solar atmosphere models include non-LTE corrections and 3D hydrodynamic convection simulations. These models predict a significant reduction in the solar metal abundance, which leads to a serious conflict between helioseismic data and the predictions of solar interiors models. We demonstrate that the helioseismic constraints on the surface convection zone depth and helium abundance combined with stellar interiors models can be used to define the goodness of fit for a given chemical composition. After a detailed examination of the errors in the theoretical models we conclude that models constructed with the older solar abundances are consistent (seismic data. Models constructed with the proposed new low abundance scale are strongly disfavored, disagreeing at the 15 \\sigma level. We then use the sensitivity of the seismic properties to abundance changes to invert the problem and infer a seismic solar heavy element abundance mix with two components: meteoritic abundances, and th...

  20. Global Power Solutions LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, search OpenEI Reference LibraryAddInformation

  1. Energy and Power Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand JumpConceptual Model,DOEHazel Crest,EnergySerranopolis JumpESL Jump to:Costa Mesa, California Zip:

  2. Mobile Power Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluatingGroup |JilinLu anMicrogreen Polymers IncMississippi:Miyi ChengnanMobileMobile

  3. Eco Power Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489 No revision| Open Jump to:(RES-AEI)CoastSodaEcho 1-7

  4. Abundance ratios in hierarchical galaxy formation

    E-Print Network [OSTI]

    D. Thomas

    1999-01-18T23:59:59.000Z

    The chemical enrichment and stellar abundance ratios of galaxies which form in a hierarchical clustering scheme are calculated. For this purpose I adopt the star formation histories (SFH) as they are delivered by semi-analytic models in Kauffmann (1996}. It turns out that the average SFH of cluster ellipticals does not yield globally alpha-enhanced stellar populations. The star burst that occurs when the elliptical forms in the major merger plays therefore a crucial role in producing alpha-enhancement. Only under the assumption that the IMF is significantly flattened with respect to the Salpeter value during the burst, a Mg/Fe overabundant population can be obtained. In particular for the interpretation of radial gradients in metallicity and alpha-enhancement, the mixing of global and burst populations are of great importance. The model predicts bright field galaxies to be less alpha-enhanced than their counterparts in clusters.

  5. Combustion Exhaust Gas Heat to Power usingThermoelectric Engines...

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

    Solutions Combustion Exhaust Gas Heat to Power using Thermoelectric Engines John LaGrandeur October 5, 2011 Advanced Thermoelectric Solutions - 1 - Market motivation based on CO 2...

  6. NATURE MATERIALS | VOL 13 | MARCH 2014 | www.nature.com/naturematerials 233 hotovoltaic devices --which convert abundant, free solar

    E-Print Network [OSTI]

    - and downconversion11 , technologies that, like the multi-junction strategy, offer a roadmap beyond the Shockley dot photovoltaics Xinzheng Lan1,2 , Silvia Masala1,3 and Edward H. Sargent1 * The solar -- which convert abundant, free solar radiation into electric power -- are increasingly required to offer

  7. Planning Amid Abundance: Alaska’s FY 2013 Budget Process

    E-Print Network [OSTI]

    McBeath, Jerry

    2013-01-01T23:59:59.000Z

    state’s incentives for oil investment are excessive” (FDNM,increased oil industry investment. Planning Amid Abundance:oil corporations said that additional investment was

  8. Earth's most abundant mineral finally has a name | Argonne National...

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

    clarified the definition of Bridgmanite, a high-density form of magnesium iron silicate and the Earth's most abundant mineral - using Argonne National Laboratory's Advanced...

  9. Oxygen abundances in the most oxygen-rich spiral galaxies

    E-Print Network [OSTI]

    L. S. Pilyugin; T. X. Thuan; J. M. Vilchez

    2006-01-06T23:59:59.000Z

    Oxygen abundances in the spiral galaxies expected to be richest in oxygen are estimated. The new abundance determinations are based on the recently discovered ff-relation between auroral and nebular oxygen line fluxes in HII regions. We find that the maximum gas-phase oxygen abundance in the central regions of spiral galaxies is 12+log(O/H)~8.75. This value is significantly lower than the previously accepted value. The central oxygen abundance in the Milky Way is similar to that in other large spirals.

  10. Enhanced Detection of Low Abundant Human Plasma Proteins using...

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

    it especially difficult to detect low-abundant proteins in human biofluids such as blood plasma, an essential aspect for successful biomarker discovery efforts. Here we...

  11. High-Performance Thermoelectric Devices Based on Abundant Silicide...

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

    Development of high-performance thermoelectric devices for vehicle waste heat recovery will include fundamental research to use abundant promising low-cost thermoelectric...

  12. Comparing halo bias from abundance and clustering

    E-Print Network [OSTI]

    Hoffmann, Kai; Gaztanaga, Enrique

    2015-01-01T23:59:59.000Z

    We model the abundance of haloes in the $\\sim(3 \\ \\text{Gpc}/h)^3$ volume of the MICE Grand Challenge simulation by fitting the universal mass function with an improved Jack-Knife error covariance estimator that matches theory predictions. We present unifying relations between different fitting models and new predictions for linear ($b_1$) and non-linear ($c_2$ and $c_3$) halo clustering bias. Different mass function fits show strong variations in their overall poor performance when including the low mass range ($M_h \\lesssim 3 \\ 10^{12} \\ M_{\\odot}/h$) in the analysis, which indicates noisy friends-of-friends halo detection given the MICE resolution ($m_p \\simeq 3 \\ 10^{10} \\ M_{\\odot}$/h). Together with fits from the literature we find an overall variance in the amplitudes of around $10%$ in the low mass and up to $50%$ in the high mass (galaxy cluster) range ($M_h > 10^{14} \\ M_{\\odot}/h$). These variations propagate into a $10%$ change in $b_1$ predictions and a $50%$ change in $c_2$ or $c_3$. Despite the...

  13. CHEMICAL ABUNDANCES IN CLUSTERS OF GALAXIES

    E-Print Network [OSTI]

    Francesca Matteucci; Brad K. Gibson

    1995-03-14T23:59:59.000Z

    We study the origin of iron and alpha-elements (O, Mg, Si) in clusters of galaxies. In particular, we discuss the [O/Fe] ratio and the iron mass-to-luminosity ratio in the intracluster medium (ICM) and their link to the chemical and dynamical evolution of elliptical and lenticular galaxies. We adopt a detailed model of galactic evolution incorporating the development of supernovae- driven galactic winds which pollute the ICM with enriched ejecta. We demonstrate \\it quantitatively \\rm the crucial dependence upon the assumed stellar initial mass function in determining the evolution of the mass and abundances ratios of heavy elements in typical model ICMs. We show that completely opposite behaviours of [alpha/Fe] ratios (\\ie positive versus negative ratios) can be obtained by varying the initial mass function without altering the classic assumptions regarding type Ia supernovae progenitors or their nucleosynthesis. Our results indicate that models incorporating somewhat flatter-than-Salpeter initial mass functions (ie x approx 1, as opposed to x=1.35) are preferred, provided the intracluster medium iron mass-to-luminosity ratio, preliminary [alpha/Fe]>0 ASCA results, and present-day type Ia supernovae rates, are to be matched. A simple Virgo cluster simulation which adheres to these constraints shows that approx 70% of the measured ICM iron mass has its origin in type II supernovae, with the remainder being synthesized in type Ia systems.

  14. Europium Isotopic Abundances in Very Metal-poor Stars

    E-Print Network [OSTI]

    Christopher Sneden; John J. Cowan; James E. Lawler; Scott Burles; Timothy C. Beers; George M. Fuller

    2002-01-28T23:59:59.000Z

    Europium isotopic abundance fractions are reported for the very metal-poor, neutron-capture-rich giant stars CS 22892-052, HD 115444, and BD +17 3248. The abundance fractions, derived from analysis of several strong Eu II lines appearing in high-resolution spectra of these stars, are in excellent agreement with each other and with their values in the Solar System: fraction(\\iso{Eu}{151}) ~= fraction(\\iso{Eu}{153}) ~= 0.5. Detailed abundance studies of very metal-poor stars have previously shown that the total elemental abundances of stable atoms with atomic numbers z >= 56 typically match very closely those of a scaled solar-system r-process abundance distribution. The present results for the first time extend this agreement to the isotopic level.

  15. Axisymmetric stationary solutions with arbitrary multipole moments

    E-Print Network [OSTI]

    Thomas Bäckdahl

    2006-12-07T23:59:59.000Z

    In this paper, the problem of finding an axisymmetric stationary spacetime from a specified set of multipole moments, is studied. The condition on the multipole moments, for existence of a solution, is formulated as a convergence condition on a power series formed from the multipole moments. The methods in this paper can also be used to give approximate solutions to any order as well as estimates on each term of the resulting power series.

  16. Optimization Online - A stabilized model and an efficient solution ...

    E-Print Network [OSTI]

    Vincent Guigues

    2011-02-24T23:59:59.000Z

    Feb 24, 2011 ... A stabilized model and an efficient solution method for the yearly optimal power management. Vincent Guigues(vguigues ***at*** puc-rio.br).

  17. Optimization Online - An exact solution method for binary ...

    E-Print Network [OSTI]

    Daniel Huppmann

    2015-04-22T23:59:59.000Z

    Apr 22, 2015 ... We apply the solution approach to a stylized nodal power-market equilibrium ... Category 3: Applications -- OR and Management Sciences.

  18. Energy Storage for the Power Grid

    SciTech Connect (OSTI)

    Wang, Wei; Imhoff, Carl; Vaishnav, Dave

    2014-04-23T23:59:59.000Z

    The iron vanadium redox flow battery was developed by researchers at Pacific Northwest National Laboratory as a solution to large-scale energy storage for the power grid.

  19. Energy Storage for the Power Grid

    ScienceCinema (OSTI)

    Wang, Wei; Imhoff, Carl; Vaishnav, Dave

    2014-06-12T23:59:59.000Z

    The iron vanadium redox flow battery was developed by researchers at Pacific Northwest National Laboratory as a solution to large-scale energy storage for the power grid.

  20. CRSP Power Marketing and Contracts default

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

    Adjustment Schedule For Long-Term Solution (pdf) GC Lake Elevations Graph - 82003 Hydrology Study (pdf) Generation Forecast Graph - 82003 Hydrology Study(pdf) Power...

  1. On the deduction of galaxy abundances with evolutionary neural networks

    E-Print Network [OSTI]

    Michael Taylor; Angeles I. Diaz

    2007-09-19T23:59:59.000Z

    A growing number of indicators are now being used with some confidence to measure the metallicity(Z) of photoionisation regions in planetary nebulae, galactic HII regions(GHIIRs), extra-galactic HII regions(EGHIIRs) and HII galaxies(HIIGs). However, a universal indicator valid also at high metallicities has yet to be found. Here, we report on a new artificial intelligence-based approach to determine metallicity indicators that shows promise for the provision of improved empirical fits. The method hinges on the application of an evolutionary neural network to observational emission line data. The network's DNA, encoded in its architecture, weights and neuron transfer functions, is evolved using a genetic algorithm. Furthermore, selection, operating on a set of 10 distinct neuron transfer functions, means that the empirical relation encoded in the network solution architecture is in functional rather than numerical form. Thus the network solutions provide an equation for the metallicity in terms of line ratios without a priori assumptions. Tapping into the mathematical power offered by this approach, we applied the network to detailed observations of both nebula and auroral emission lines in the optical for a sample of 96 HII-type regions and we were able to obtain an empirical relation between Z and S23 with a dispersion of only 0.16 dex. We show how the method can be used to identify new diagnostics as well as the nonlinear relationship supposed to exist between the metallicity Z, ionisation parameter U and effective (or equivalent) temperature T*.

  2. Analysis and design of power conditioning systems 

    E-Print Network [OSTI]

    Harfman Todorovic, Maja

    2009-05-15T23:59:59.000Z

    power conditioner consisting of DC-DC and DC-AC converters is required for load interface. The design of power conditioners is driven by the application. This dissertation presents several different solutions for applications ranging from low...

  3. Beryllium Abundances in Stars of One-Solar-Mass

    E-Print Network [OSTI]

    Ann Merchant Boesgaard; Julie A. Krugler

    2008-09-26T23:59:59.000Z

    We have determined Be abundances in 50 F and G dwarfs in the mass range of 0.9 $\\leq$ M$_\\odot$ $\\leq$ 1.1 as determined by Lambert & Reddy. The effective temperatures are 5600 to 6400 K and metallicities from $-$0.65 to +0.11. The spectra were taken primarily with Keck I + HIRES. The Be abundances were found via spectral synthesis of Be II lines near 3130 \\AA. The Be abundances were investigated as a function of age, temperature, metallicity and Li abundance in this narrow mass range. Even though our stars are similar in mass, they show a range in Be abundances of a factor of $>$40. We find that [Be/Fe] has no dependence on temperature, but does show a spread of a factor of 6 at a given temperature. The reality of the spread is shown by two identical stars which differ from each other by a factor of two only in their abundances of Li and Be. Our thin-disk-star sample fits the trend between Be abundance and [Fe/H] found for halo and thick disk stars, extending it to about 4 orders of magnitude in the two logarithmic quantities. Both Fe and Be appear to increase similarly over time in the Galaxy. One-third of our sample may be classified as subgiants; these more-evolved stars have lower Be abundances than the dwarfs. They have undergone Be depletion by slow mixing on the main sequence and Be dilution during their trip toward the red giant base. There are both Li and Be detections in 60 field stars in the "Li-plateau" of 5900 - 6300 K now and the abundances of the two light elements are correlated with a slope of 0.34 $\\pm$0.05, with greater Li depletion than Be depletion.

  4. ISO SWS Observations of H II Regions in NGC 6822 and I ZW 36: Sulfur Abundances and Temperature Fluctuations

    E-Print Network [OSTI]

    Joshua G. Nollenberg; Evan D. Skillman; Donald R. Garnett; Harriet L. Dinerstein

    2002-09-04T23:59:59.000Z

    We report ISO SWS infrared spectroscopy of the H II region Hubble V in NGC 6822 and the blue compact dwarf galaxy I Zw 36. Observations of Br alpha, [S III] at 18.7 and 33.5 microns, and [S IV] at 10.5 microns are used to determine ionic sulfur abundances in these H II regions. There is relatively good agreement between our observations and predictions of S^+3 abundances based on photoionization calculations, although there is an offset in the sense that the models overpredict the S^+3 abundances. We emphasize a need for more observations of this type in order to place nebular sulfur abundance determinations on firmer ground. The S/O ratios derived using the ISO observations in combination with optical data are consistent with values of S/O, derived from optical measurements of other metal-poor galaxies. We present a new formalism for the simultaneous determination of the temperature, temperature fluctuations, and abundances in a nebula, given a mix of optical and infrared observed line ratios. The uncertainties in our ISO measurements and the lack of observations of [S III] lambda 9532 or lambda 9069 do not allow an accurate determination of the amplitude of temperature fluctuations for Hubble V and I Zw 36. Finally, using synthetic data, we illustrate the diagnostic power and limitations of our new method.

  5. Chemical Feature of Eu abundance in the Draco dwarf spheroidal galaxy

    E-Print Network [OSTI]

    Tsujimoto, Takuji; Shigeyama, Toshikazu; Aoki, Wako

    2015-01-01T23:59:59.000Z

    Chemical abundance of r-process elements in nearby dwarf spheroidal (dSph) galaxies is a powerful tool to probe the site of r-process since their small-mass scale can sort out individual events producing r-process elements. A merger of binary neutron stars is a promising candidate of this site. In faint, or less massive dSph galaxies such as the Draco, a few binary neutron star mergers are expected to have occurred at most over the whole past. We have measured chemical abundances including Eu and Ba of three red giants in the Draco dSph by Subaru/HDS observation. The Eu detection for one star with [Fe/H]=-1.45 confirms a broadly constant [Eu/H] of ~-1.3 for stars with [Fe/H]>-2. This feature is shared by other dSphs with similar masses, i.e., the Sculptor and the Carina, and suggests that neutron star merger is the origin of r-process elements in terms of its rarity. In addition, two very metal-poor stars with [Fe/H]=-2.12 and -2.51 are found to exhibit very low Eu abundances such as [Eu/H]<-2 with an impl...

  6. Origin of the heavy elements in HD 140283. Measurement of europium abundance

    E-Print Network [OSTI]

    Mello, C Siqueira; Spite, M; Spite, F

    2012-01-01T23:59:59.000Z

    HD 140283 is a nearby (V=7.7) subgiant metal-poor star, extensively analysed in the literature. Although many spectra have been obtained for this star, none showed a signal-to-noise (S/N) ratio high enough to enable a very accurate derivation of abundances from weak lines. The detection of europium proves that the neutron-capture elements in this star originate in the r-process, and not in the s-process, as recently claimed in the literature. Based on the OSMARCS 1D LTE atmospheric model and with a consistent approach based on the spectrum synthesis code Turbospectrum, we measured the europium lines at 4129 {\\AA} and 4205 {\\AA}, taking into account the hyperfine structure of the transitions. The spectrum, obtained with a long exposure time of seven hours at the Canada-France-Hawaii Telescope (CFHT), has a resolving power of 81000 and a S/N ratio of 800 at 4100 {\\AA}. We were able to determine the abundance A(Eu)=-2.35 dex, compatible with the value predicted for the europium from the r-process. The abundance ...

  7. Wireless Power Transmission An Obscure History and a Bright Future?

    E-Print Network [OSTI]

    La Rosa, Andres H.

    to the distant rectenna site over a distance of 1.6 km. The dc output was 30 kW." [2] [5] #12;Solar Power transmission. Solar Power Satellite to Earth Terminal. Desert Solar Power Farm to Civilization. Earth Terminal solution to the coming power shortage . . . Solar Power Satellites (SPS) (4) #12;Solar Power Satellites (5

  8. Oxygen and nitrogen abundances in Virgo and field spirals

    E-Print Network [OSTI]

    L. S. Pilyugin; Mercedes Molla; Federico Ferrini; Jose M. Vilchez

    2001-12-03T23:59:59.000Z

    The oxygen and nitrogen abundances in the HII regions of the nine Virgo spirals of the sample from Skillman et al (1996) and in nine field spiral galaxies are re-determined with the recently suggested P - method. We confirm that there is an abundance segregation in the sample of Virgo spirals in the sense that the HI deficient Virgo spirals near the core of the cluster have higher oxygen abundances in comparison to the spirals at the periphery of the Virgo cluster. At the same time both the Virgo periphery and core spirals have counterparts among field spirals. We conclude that if there is a difference in the abundance properties of the Virgo and field spirals, this difference appears to be small and masked by the observational errors.

  9. astrophysically abundant atoms: Topics by E-print Network

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

    atomic data available so far and check the Mg abundances from individual lines in the Sun, four well studied A-type stars, and three reference metal-poor stars. With the adopted...

  10. abundance element: Topics by E-print Network

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

    physics, enable us to infer the temperature and hydrogen abundance profiles inside the Sun. These profiles also help in setting constraints on the input physics as well as on...

  11. Fundamental constraints on the abundances of chemotaxis proteins

    E-Print Network [OSTI]

    Bitbol, Anne-Florence

    2015-01-01T23:59:59.000Z

    Flagellated bacteria, such as Escherichia coli, perform directed motion in gradients of concentration of attractants and repellents in a process called chemotaxis. The E. coli chemotaxis signaling pathway is a model for signal transduction, but it has unique features. We demonstrate that the need for fast signaling necessitates high abundances of the proteins involved in this pathway. We show that further constraints on the abundances of chemotaxis proteins arise from the requirements of self-assembly, both of flagellar motors and of chemoreceptor arrays. All these constraints are specific to chemotaxis, and published data confirm that chemotaxis proteins tend to be more highly expressed than their homologs in other pathways. Employing a chemotaxis pathway model, we show that the gain of the pathway at the level of the response regulator CheY increases with overall chemotaxis protein abundances. This may explain why, at least in one E. coli strain, the abundance of all chemotaxis proteins is higher in media w...

  12. animal prey abundance: Topics by E-print Network

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

    overall abundance was higher overall during the August 1997 cruise than during the October 1996 cruise... Cady, Robert B 2012-06-07 42 The camp will expose students to local...

  13. abundance mineral: Topics by E-print Network

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

    between 55 and 72 Sm II lines per star. The abundance ratios of Sm relative to other rare earth elements in these stars are in agreement, and are consistent with ratios...

  14. Relative abundance of desert tortoises on the Nevada Test Site

    SciTech Connect (OSTI)

    Rautenstrauch, K.R.; O`Farrell, T.P.

    1993-12-31T23:59:59.000Z

    Seven hundred fifty-nine transects having a total length of 1,191 km were walked during 1981--1986 to determine the distribution and relative abundance of desert tortoises (Gopherus agassizii) on the Nevada Test Site (NTS). The abundance of tortoises on NTS was low to very low relative to other populations in the Mojave Desert. Sign of tortoises was found from 880 to 1,570 m elevation and was more abundant above 1,200 m than has been reported previously for Nevada. Tortoises were more abundant on NTS on the upper alluvial fans and slopes of mountains than in valley bottoms. They also were more common on or near limestone and dolomite mountains than on mountains of volcanic origin.

  15. A Temperature and Abundance Retrieval Method for Exoplanet Atmospheres

    E-Print Network [OSTI]

    Madhusudhan, Nikku

    We present a new method to retrieve molecular abundances and temperature profiles from exoplanet atmosphere photometry and spectroscopy. We run millions of one-dimensional (1D) atmosphere models in order to cover the large ...

  16. Relationships between body size and abundance in ecology

    E-Print Network [OSTI]

    Enquist, Brian Joseph

    , but interrelated, relation- ships between size and abundance that are often con- fused in the literature. Here, we and the structure and dynamics of eco- logical communities [3­5]. In addition, because body size is one

  17. Planning Amid Abundance: Alaska’s FY 2013 Budget Process

    E-Print Network [OSTI]

    McBeath, Jerry

    2013-01-01T23:59:59.000Z

    2011) “The Outlier State: Alaska’s FY 2012 Budget,” AnnualWestern States Budget Review. New York Times, selectedAbundance: Alaska’s FY 2013 Budget Process Abstract: This

  18. abundance isotopic: Topics by E-print Network

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

    24 Abundances and Isotope Ratios in the Magellanic Clouds: The Star Forming Environment of N113 Astrophysics (arXiv) Summary: With the goal of deriving the physical and...

  19. Beryllium, Lithium and Oxygen Abundances in F-type Stars

    E-Print Network [OSTI]

    R. J. Garcia Lopez; M. C. Dominguez Herrera; M. R. Perez de Taoro; C. Casares; J. L. Rasilla; R. Rebolo; C. Allende Prieto

    1997-10-07T23:59:59.000Z

    Beryllium and oxygen abundances have been derived in a sample of F-type field stars for which lithium abundances had been measured previously, with the aim of obtaining observational constraints to discriminate between the different mixing mechanisms proposed. Mixing associated with the transport of angular momentum in the stellar interior and internal gravity waves within the framework of rotating evolutionary models, appear to be promising ways to explain the observations.

  20. Massive stars vs. nebular abundances in the Orion nebula

    E-Print Network [OSTI]

    Sergio Simón Díaz

    2006-11-16T23:59:59.000Z

    The search of consistency between nebular and massive star abundances has been a longstanding problem. I briefly review what has been done regarding to this topic, also presenting a recent study focused on the Orion nebula: the O and Si stellar abundances resulting from a detailed and fully consistent spectroscopic analysis of the group of B stars associated with the Orion nebula are compared with the most recent nebular gas-phase results.

  1. Rate Analysis or a Possible Interpretation of Abundances

    E-Print Network [OSTI]

    Miklos Kiss

    2015-02-24T23:59:59.000Z

    Heavy elements are formed in nucleosynthesis processes. Abundances of these elements can be classified as elemental abundance, isotopic abundance, and abundance of nuclei. In this work we propose to change nucleon identification from the usual (Z,A) to (Z,N), which allows reading out new information from the measured abundances. We are interested in the neutron density required to reproduce the measured abundance of nuclei assuming equilibrium processes. This is only possible when two stable nuclei are separated by an unstable nucleus. At these places we investigated the neutron density required for equilibrium nucleosynthesis both isotopically and isotonically at temperatures of AGB interpulse and thermal pulse phases. We obtained an estimate for equilibrium nucleosynthesis neutron density in most of the cases. Next we investigated the possibility of partial formation of nuclei. We analyzed the meaning of the branching factor. We found a mathematical definition for the unified interpretation of a branching point closed at isotonic case and open at isotopic case. We introduce a more expressive variant of branching ratio called partial formation rate. With these we are capable of determining the characteristic neutron density values.

  2. DIRECT EVALUATION OF THE HELIUM ABUNDANCES IN OMEGA CENTAURI

    SciTech Connect (OSTI)

    Dupree, A. K.; Avrett, E. H., E-mail: dupree@cfa.harvard.edu, E-mail: eavrett@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2013-08-20T23:59:59.000Z

    A direct measure of the helium abundances from the near-infrared transition of He I at 1.08 {mu}m is obtained for two nearly identical red giant stars in the globular cluster Omega Centauri. One star exhibits the He I line; the line is weak or absent in the other star. Detailed non-local thermal equilibrium semi-empirical models including expansion in spherical geometry are developed to match the chromospheric H{alpha}, H{beta}, and Ca II K lines, in order to predict the helium profile and derive a helium abundance. The red giant spectra suggest a helium abundance of Y {<=} 0.22 (LEID 54064) and Y = 0.39-0.44 (LEID 54084) corresponding to a difference in the abundance {Delta}Y {>=} 0.17. Helium is enhanced in the giant star (LEID 54084) that also contains enhanced aluminum and magnesium. This direct evaluation of the helium abundances gives observational support to the theoretical conjecture that multiple populations harbor enhanced helium in addition to light elements that are products of high-temperature hydrogen burning. We demonstrate that the 1.08 {mu}m He I line can yield a helium abundance in cool stars when constraints on the semi-empirical chromospheric model are provided by other spectroscopic features.

  3. Primordial Lithium Abundance in Catalyzed Big Bang Nucleosynthesis

    E-Print Network [OSTI]

    Chris Bird; Kristen Koopmans; Maxim Pospelov

    2008-05-19T23:59:59.000Z

    There exists a well known problem with the Li7+Be7 abundance predicted by standard big bang nucleosynthesis being larger than the value observed in population II stars. The catalysis of big bang nucleosynthesis by metastable, \\tau_X \\ge 10^3 sec, charged particles X^- is capable of suppressing the primordial Li7+Be7, abundance and making it consistent with the observations. We show that to produce the correct abundance, this mechanism of suppression places a requirement on the initial abundance of X^- at temperatures of 4\\times 10^8 K to be on the order of or larger than 0.02 per baryon, which is within the natural range of abundances in models with metastable electroweak-scale particles. The suppression of Li7+Be7, is triggered by the formation of (Be7X^-), compound nuclei, with fast depletion of their abundances by catalyzed proton reactions, and in some models by direct capture of X^- on Be7. The combination of Li7+Be7 and Li6 constraints favours the window of lifetimes, 1000s \\la tau_X \\leq 2000 s.

  4. Carbon and Strontium Abundances of Metal-Poor Stars

    E-Print Network [OSTI]

    David K. Lai; Jennifer A. Johnson; Michael Bolte; Sara Lucatello

    2007-06-20T23:59:59.000Z

    We present carbon and strontium abundances for 100 metal-poor stars measured from R$\\sim $7000 spectra obtained with the Echellette Spectrograph and Imager at the Keck Observatory. Using spectral synthesis of the G-band region, we have derived carbon abundances for stars ranging from [Fe/H]$=-1.3$ to [Fe/H]$=-3.8$. The formal errors are $\\sim 0.2$ dex in [C/Fe]. The strontium abundance in these stars was measured using spectral synthesis of the resonance line at 4215 {\\AA}. Using these two abundance measurments along with the barium abundances from our previous study of these stars, we show it is possible to identify neutron-capture-rich stars with our spectra. We find, as in other studies, a large scatter in [C/Fe] below [Fe/H]$ = -2$. Of the stars with [Fe/H]$carbon-rich metal-poor stars. The Sr and Ba abundances show that three of the carbon-rich stars are neutron-capture-rich, while two have normal Ba and Sr. This fraction of carbon enhanced stars is consistent with other studies that include this metallicity range.

  5. A search for stars of very low metal abundance. VI. Detailed abundances of 313 metal-poor stars

    SciTech Connect (OSTI)

    Roederer, Ian U.; Preston, George W.; Thompson, Ian B.; Shectman, Stephen A.; Burley, Gregory S.; Kelson, Daniel D. [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Sneden, Christopher, E-mail: iur@umich.edu [Department of Astronomy, University of Texas at Austin, 1 University Station, C1400, Austin, TX 78712 (United States)

    2014-06-01T23:59:59.000Z

    We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10 yr observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coudé Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by ?0.25 dex for red giants and ?0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] ?–3.5, 84 stars with [Fe/H] ?–3.0, and 210 stars with [Fe/H] ?–2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] ?–2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers.

  6. Lithium Abundances of the Local Thin Disk Stars

    E-Print Network [OSTI]

    David L. Lambert; Bacham E. Reddy

    2004-01-14T23:59:59.000Z

    Lithium abundances are presented for a sample of 181 nearby F and G dwarfs with accurate {\\it Hipparcos} parallaxes. The stars are on circular orbits about the Galactic centre and, hence, are identified as belonging to the thin disk. This sample is combined with two published surveys to provide a catalogue of lithium abundances, metallicities ([Fe/H]), masses, and ages for 451 F-G dwarfs, almost all belonging to the thin disk. The lithium abundances are compared and contrasted with published lithium abundances for F and G stars in local open clusters. The field stars span a larger range in [Fe/H] than the clusters for which [Fe/H] $\\simeq 0.0\\pm0.2$. The initial (i.e., interstellar) lithium abundance of the solar neighborhood, as derived from stars for which astration of lithium is believed to be unimportant, is traced from $\\log\\epsilon$(Li) = 2.2 at [Fe/H] = -1 to $\\log\\epsilon$(Li) = 3.2 at $+0.1$. This form for the evolution is dependent on the assumption that astration of lit hium is negligible for the stars defining the relation. An argument is advanced that this latter assumption may not be entirely correct, and, the evolution of lithium with [Fe/H] may be flatter than previously supposed. A sharp Hyades-like Li-dip is not seen among the field stars and appears to be replaced by a large spread among lithium abundances of stars more massive than the lower mass limit of the dip. Astration of lithium by stars of masses too low to participate in the Li-dip is discussed. These stars show little to no spread in lithium abundance at a given [Fe/H] and mass.

  7. Spatial Mapping of Protein Abundances in the Mouse Brain by Voxelation...

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

    Mapping of Protein Abundances in the Mouse Brain by Voxelation Integrated with High-Throughput Liquid Chromatography Spatial Mapping of Protein Abundances in the Mouse Brain by...

  8. The Space Power Grid: Synergy Between Space, Energy and Security Policies

    E-Print Network [OSTI]

    @gatech.edu Abstract - The dream of abundant solar-powered electricity from Space can be realized through global ­ Space solar power, renewable energy, climate policy, global warming, infrastructure, power grid electric power can be generated "24/365" in Space, and conveyed down to Earth. Many concepts have been

  9. The relation of coastal water level and postlarval abundance of estuarine-recruiting species of the northwest Gulf of Mexico

    E-Print Network [OSTI]

    Craddock, Patti Powers

    1988-01-01T23:59:59.000Z

    TIIE RELATION OF COASTAL WATER LEVEL AND I'OSTLARVAL ABUNDANCF. OF ESTUAPINE-RECRUITING SPECIES OF THF. NORTIIWEST GULF OF MEXICO A Thesis PATTI POWERS CRADDOCK Submitted to the Graduate College of Texas AkM University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE Ivlag I988 Major Subject: Civii Engineering THE RELATION OF COASTAL WATER LEVEL AND POSTLARVAL ABUNDANCE OF ESTUARINE-RECRUITING SPECIES OF THE NORTHWEST GULF OF MEXICO A Thesis by PATTI POWERS CRADDOCK...

  10. Synthesis and Characterization of Earth Abundant and Nontoxic Metal Chalcogenides Produced via Aerosol Spray Pyrolysis for Photovoltaic Applications

    E-Print Network [OSTI]

    Davis, Patrick John

    2013-01-01T23:59:59.000Z

    and Characterization of Earth Abundant and Nontoxic Metaland Characterization of Earth Abundant and Nontoxic Metalalternatives to CIGS with all earth abundant and non-toxic

  11. New solar opacities, abundances, helioseismology, and neutrino fluxes

    E-Print Network [OSTI]

    John N. Bahcall; Aldo M. Serenelli; Sarbani Basu

    2005-01-19T23:59:59.000Z

    We construct solar models with the newly calculated radiative opacities from the Opacity Project (OP) and recently determined (lower) heavy element abundances. We compare results from the new models with predictions of a series of models that use OPAL radiative opacities, older determinations of the surface heavy element abundances, and refinements of nuclear reaction rates. For all the variations we consider, solar models that are constructed with the newer and lower heavy element abundances advocated by Asplund et al. (2005) disagree by much more than the estimated measuring errors with helioseismological determinations of the depth of the solar convective zone, the surface helium composition, the internal sound speeds, and the density profile. Using the new OP radiative opacities, the ratio of the 8B neutrino flux calculated with the older and larger heavy element abundances (or with the newer and lower heavy element abundances) to the total neutrino flux measured by the Sudbury Neutrino Observatory is 1.09 (0.87) with a 9% experimental uncertainty and a 16% theoretical uncertainty, 1 sigma errors.

  12. Spectroscopic Study on the Beryllium Abundances of Red Giant Stars

    E-Print Network [OSTI]

    Takeda, Yoichi

    2014-01-01T23:59:59.000Z

    An extensive spectroscopic study was carried out for the beryllium abundances of 200 red giants (mostly of late G and early K type), which were determined from the near-UV Be II 3131.066 line based on high-dispersion spectra obtained by Subaru/HDS, with an aim of investigating the nature of surface Be contents in these evolved giants; e.g., dependence upon stellar parameters, degree of peculiarity along with its origin and build-up timing. We found that Be is considerably deficient (to widely different degree from star to star) in the photosphere of these evolved giants by ~1-3 dex (or more) compared to the initial abundance. While the resulting Be abundances (A(Be)) appear to weakly depend upon T_eff, log g, [Fe/H], M, age, and v_sin i, this may be attributed to the metallicity dependence of A(Be) coupled with the mutual correlation between these stellar parameters, since such tendencies almost disappear in the metallicity-scaled Be abundance ([Be/Fe]). By comparing the Be abundances (as well as their correl...

  13. Oxygen abundance in the Sloan Digital Sky Survey

    E-Print Network [OSTI]

    F. Shi; X. Kong; F. Z. Cheng

    2006-03-10T23:59:59.000Z

    We present two samples of $\\hii$ galaxies from the Sloan Digital Sky Survey (SDSS) spectroscopic observations data release 3. The electron temperatures($T_e$) of 225 galaxies are calculated with the photoionized $\\hii$ model and $T_e$ of 3997 galaxies are calculated with an empirical method. The oxygen abundances from the $T_e$ methods of the two samples are determined reliably. The oxygen abundances from a strong line metallicity indicator, such as $R_{23}$, $P$, $N2$, and $O3N2$, are also calculated. We compared oxygen abundances of $\\hii$ galaxies obtained with the $T_e$ method, $R_{23}$ method, $P$ method, $N2$ method, and $O3N2$method. The oxygen abundances derived with the $T_e$ method are systematically lower by $\\sim$0.2 dex than those derived with the $R_{23}$ method, consistent with previous studies based on $\\hii$ region samples. No clear offset for oxygen abundance was found between $T_e$ metallicity and $P$, $N2$ and $O3N2$ metallicity. When we studied the relation between N/O and O/H, we found that in the metallicity regime of $\\zoh > 7.95$, the large scatter of the relation can be explained by the contribution of small mass stars to the production of nitrogen. In the high metallicity regime, $\\zoh > 8.2$, nitrogen is primarily a secondary element produced by stars of all masses.

  14. Nuclear Power PROS -`No' greenhouse gas emissions

    E-Print Network [OSTI]

    Toohey, Darin W.

    /transporting U! Coal Power PROS -Cheep -Easy to attain (Russia and US) -Infrastructure and technology well known provides a clean base load electricity that produces waste just a size of a coke can as compared to a coal,000 tons of coal to produce same amount of electricity) -Natural abundance of U (48th among the most

  15. What Is The Neon Abundance Of The Sun?

    E-Print Network [OSTI]

    John N. Bahcall; Sarbani Basu; Aldo M. Serenelli

    2005-05-16T23:59:59.000Z

    We have evolved a series of thirteen complete solar models that utilize different assumed heavy element compositions. Models that are based upon the heavy element abundances recently determined by Asplund, Grevesse, and Sauval (2005) are inconsistent with helioseismological measurements. However, models in which the neon abundance is increased by 0.4-0.5 dex to log N(Ne) = 8.29 +- 0.05 (on the scale in which log N(H) = 12) are consistent with the helioseismological measurements even though the other heavy element abundances are in agreement with the determinations of Asplund et al. (2005). These results sharpen and strengthen an earlier study by Antia and Basu (2005). The predicted solar neutrino fluxes are affected by the uncertainties in the composition by less than their 1sigma theoretical uncertainties.

  16. The chemical abundances of the Ap star HD94660

    SciTech Connect (OSTI)

    Giarrusso, M. [Università di Catania, Dipartimento di Fisica e Astronomia, Sezione Astrofisica, Via S. Sofia 78, 95123 Catania (Italy); INAF - Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania (Italy); INFN - Laboratori Nazionali del Sud (Italy)

    2014-05-09T23:59:59.000Z

    In this work I present the determination of chemical abundances of the Ap star HD94660, a possible rapid oscillating star. As all the magnetic chemically peculiar objects, it presents CNO underabundance and overabundance of iron peak elements of ?100 times and of rare earths up to 4 dex with respect to the Sun. The determination was based on the conversion of the observed equivalent widths into abundances simultaneously to the determination of effective temperature and gravity. Since the Balmer lines of early type stars are very sensitive to the surface gravity while the flux distribution is sensitive to the effective temperature, I have adopted an iterative procedure to match the H{sub ?} line profile and the observed UV-Vis-NIR magnitudes of HD94660 looking for a consistency between the metallicity of the atmosphere model and the derived abundances. From my spectroscopic analysis, this star belongs to the no-rapid oscillating class.

  17. Abundant p-singular elements in finite classical groups

    E-Print Network [OSTI]

    Niemeyer, Alice C; Praeger, Cheryl E

    2012-01-01T23:59:59.000Z

    In 1995, Isaacs, Kantor and Spaltenstein proved that for a finite simple d-dimensional classical group G, and for any prime divisor p of |G| distinct from the characteristic, the proportion of p-singular elements (elements with order divisible by p) is at least c/d for some constant c. We define a new subfamily of p-singular elements, called p-abundant elements, which leave invariant certain "large" subspaces of the natural G-module. We find explicit upper and lower bounds for the proportion of p-abundant elements in G, and prove that it approaches a (positive) limiting value as d \\rightarrow \\infty. It turns out that the limiting proportion of p-abundant elements is at least a constant multiple of the lower bound for the proportion of all p-singular elements derived by Issacs, Kantor and Spaltenstein.

  18. Spectroscopic Abundances and Membership in the Wolf 630 Moving Group

    E-Print Network [OSTI]

    Bubar, Eric J

    2010-01-01T23:59:59.000Z

    The concept of kinematic assemblages evolving from dispersed stellar clusters has remained contentious since Eggen's initial formulation of moving groups in the 1960's. With high quality parallaxes from the Hipparcos space astrometry mission, distance measurements for thousands of nearby, seemingly isolated stars are currently available. With these distances, a high resolution spectroscopic abundance analysis can be brought to bear on the alleged members of these moving groups. If a structure is a relic of an open cluster, the members can be expected to be monolithic in age and abundance inasmuch as homogeneity is observed in young open clusters. In this work we have examined 34 putative members of the proposed Wolf 630 moving group using high resolution stellar spectroscopy. The stars of the sample have been chemically tagged to determine abundance homogeneity and confirm the existence of a homogeneous subsample of 19 stars. Fitting the homogeneous subsample with Yale-Yonsei isochrones yields a single evolut...

  19. The production and utilization of a clean, abundant, and renewable energy source is widely accepted as one of the key challenges facing mankind today. Population

    E-Print Network [OSTI]

    Bruck, Jehoshua (Shuki)

    The production and utilization of a clean, abundant, and renewable energy source is widely accepted-splitter and may one day be used as a source of clean energy.The components include (a) Membrane assembly of underdeveloped nations will increase our current demand for energy. Although fossil fuels may power the planet

  20. Energy Efficient Scheduling with Power Control for Wireless Networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Energy Efficient Scheduling with Power Control for Wireless Networks Bastian Katz Institute the complexity of scheduling with power control in the SINRG model of interference. Based on a novel scheme without power control are also solutions if power control is possible, power control can be exploited

  1. Independent Scientific Review Panel for the Northwest Power & Conservation Council

    E-Print Network [OSTI]

    1 Independent Scientific Review Panel for the Northwest Power & Conservation Council 851 SW 6 th, 2011 To: Bruce Measure, Chair, Northwest Power and Conservation Council From: Eric Loudenslager, ISRP lamprey behavior and vulnerability to predation may affect abundance estimates. The proponents' submittal

  2. 32 IEEE power & energy magazine september/october 20031540-7977/03/$17.002003 IEEE Active power filters

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    32 IEEE power & energy magazine september/october 20031540-7977/03/$17.00©2003 IEEE Active power filters as a solution to power quality problems in distribution networks By Hugh Rudnick, Juan Dixon and Luis Morán ©CORBISSTOCKMARKET.COM Delivering Cleanand PurePower #12;P POWER ELECTRONICS IN FACTS

  3. Asteroseismic determination of helium abundance in stellar envelopes

    E-Print Network [OSTI]

    Sarbani Basu; Anwesh Mazumdar; H. M Antia; Pierre Demarque

    2004-02-15T23:59:59.000Z

    Intermediate degree modes of the solar oscillations have previously been used to determine the solar helium abundance to a high degree of precision. However, we cannot expect to observe such modes in other stars. In this work we investigate whether low degree modes that should be available from space-based asteroseismology missions can be used to determine the helium abundance, Y, in stellar envelopes with sufficient precision. We find that the oscillatory signal in the frequencies caused by the depression in \\Gamma_1 in the second helium ionisation zone can be used to determine the envelope helium abundance of low mass main sequence stars. For frequency errors of 1 part in 10^4, we expect errors \\sigma_Y in the estimated helium abundance to range from 0.03 for 0.8M_sun stars to 0.01 for 1.2M_sun stars. The task is more complicated in evolved stars, such as subgiants, but is still feasible if the relative errors in the frequencies are less than 10^{-4}.

  4. Coronae of Stars with Super Solar Elemental Abundances

    E-Print Network [OSTI]

    Peretz, Uria; Drake, Stephen A

    2015-01-01T23:59:59.000Z

    Coronal elemental abundances are known to deviate from the photospheric values of their parent star, with the degree of deviation depending on the First Ionization Potential (FIP). This study focuses on the coronal composition of stars with super-solar photospheric abundances. We present the coronal abundances of six such stars: 11 LMi, $\\iota$ Hor, HR 7291, $\\tau$ Boo, and $\\alpha$ Cen A and B. These stars all have high-statistics X-ray spectra, three of which are presented for the first time. The abundances measured in this paper are obtained using the line-resolved spectra of the Reflection Grating Spectrometer (RGS) in conjunction with the higher throughput EPIC-pn camera spectra on board the XMM-Newton observatory. A collisionally ionized plasma model with two or three temperature components is found to represent the spectra well. All elements are found to be consistently depleted in the coronae compared to their respective photospheres. For 11 LMi and $\\tau$ Boo no FIP effect is present, while $\\iota$ H...

  5. Implications of Elemental Abundances in Dwarf Spheroidal Galaxies

    E-Print Network [OSTI]

    Takuji Tsujimoto

    2005-09-29T23:59:59.000Z

    Unusual elemental abundance patterns observed for stars belonging to nearby dwarf spheroidal (dSph) galaxies are discussed. Analysis of the [alpha/H] vs. [Fe/H] diagrams where alpha represents Mg or average of alpha-elements reveals that Fe from Type Ia supernovae (SNe Ia) does not contribute to the stellar abundances in the dSph galaxies where the member stars exhibit low alpha/Fe ratios except for the most massive dSph galaxy, the Sagitarrius. The more massive dwarf (irregular) galaxy, the Large Magellanic Cloud, also have an SNe Ia signature in the stellar abundances. These findings suggest that the condition of whether SNe Ia contribute to chemical evolution in dwarf galaxies is likely to depend on the mass scale of galaxies. Unusual Mg abundances in some dSph stars are also found to be the origin of the large scatter in the [Mg/Fe] ratios and responsible for a seemingly decreasing [Mg/Fe] feature with increasing [Fe/H]. In addition, the lack of massive stars in the dSph galaxies does not satisfactorily account for the low-alpha signature. Considering the assemblage of deficient elements (O, Mg, Si, Ca, Ti, and Zn), all of which are synthesized in pre-SN massive stars and in SN explosions, the low-alpha signature appears to reflect the heavy-element yields of massive stars with smaller rotation compared to solar neighborhood stars.

  6. Implications of Elemental Abundances in Dwarf Spheroidal Galaxies

    E-Print Network [OSTI]

    Tsujimoto, T

    2005-01-01T23:59:59.000Z

    Unusual elemental abundance patterns observed for stars belonging to nearby dwarf spheroidal (dSph) galaxies are discussed. Analysis of the [alpha/H] vs. [Fe/H] diagrams where alpha represents Mg or average of alpha-elements reveals that Fe from Type Ia supernovae (SNe Ia) does not contribute to the stellar abundances in the dSph galaxies where the member stars exhibit low alpha/Fe ratios except for the most massive dSph galaxy, the Sagitarrius. The more massive dwarf (irregular) galaxy, the Large Magellanic Cloud, also have an SNe Ia signature in the stellar abundances. These findings suggest that the condition of whether SNe Ia contribute to chemical evolution in dwarf galaxies is likely to depend on the mass scale of galaxies. Unusual Mg abundances in some dSph stars are also found to be the origin of the large scatter in the [Mg/Fe] ratios and responsible for a seemingly decreasing [Mg/Fe] feature with increasing [Fe/H]. In addition, the lack of massive stars in the dSph galaxies does not satisfactorily a...

  7. abundant energy source: Topics by E-print Network

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

    abundant energy source First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 The SolarWiki Solar energy is...

  8. Are beryllium abundances anomalous in stars with giant planets?

    E-Print Network [OSTI]

    N. C. Santos; G. Israelian; R. J Garcia Lopez; M. Mayor; R. Rebolo; S. Randich; A. Ecuvillon; C. Dominguez Cerdena

    2004-08-05T23:59:59.000Z

    In this paper we present beryllium (Be) abundances in a large sample of 41 extra-solar planet host stars, and for 29 stars without any known planetary-mass companion, spanning a large range of effective temperatures. The Be abundances were derived through spectral synthesis done in standard Local Thermodynamic Equilibrium, using spectra obtained with various instruments. The results seem to confirm that overall, planet-host stars have ``normal'' Be abundances, although a small, but not significant, difference might be present. This result is discussed, and we show that this difference is probably not due to any stellar ``pollution'' events. In other words, our results support the idea that the high-metal content of planet-host stars has, overall, a ``primordial'' origin. However, we also find a small subset of planet-host late-F and early-G dwarfs that might have higher than average Be abundances. The reason for the offset is not clear, and might be related either to the engulfment of planetary material, to galactic chemical evolution effects, or to stellar-mass differences for stars of similar temperature.

  9. abundant nuclear copies: Topics by E-print Network

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

    abundant nuclear copies First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Author's personal copy Nuclear...

  10. GASEOUS CO ABUNDANCE-AN EVOLUTIONARY TRACER FOR MOLECULAR CLOUDS

    SciTech Connect (OSTI)

    Liu Tie; Wu Yuefang; Zhang Huawei, E-mail: liutiepku@gmail.com, E-mail: ywu@pku.edu.cn [Department of Astronomy, Peking University, Beijing 100871 (China)

    2013-09-20T23:59:59.000Z

    Planck cold clumps are among the most promising objects to investigate the initial conditions of the evolution of molecular clouds. In this work, by combing the dust emission data from the survey of the Planck satellite with the molecular data of {sup 12}CO/{sup 13}CO/C{sup 18}O (1-0) lines from observations with the Purple Mountain Observatory 13.7 m telescope, we investigate the CO abundance, CO depletion, and CO-to-H{sub 2} conversion factor of 674 clumps in the early cold cores sample. The median and mean values of the CO abundance are 0.89 Multiplication-Sign 10{sup -4} and 1.28 Multiplication-Sign 10{sup -4}, respectively. The mean and median of CO depletion factor are 1.7 and 0.9, respectively. The median value of X{sub CO-to-H{sub 2}} for the whole sample is 2.8 Multiplication-Sign 10{sup 20} cm{sup -2} K{sup -1} km{sup -1} s. The CO abundance, CO depletion factor, and CO-to-H{sub 2} conversion factor are strongly (anti-)correlated to other physical parameters (e.g., dust temperature, dust emissivity spectral index, column density, volume density, and luminosity-to-mass ratio). To conclude, the gaseous CO abundance can be used as an evolutionary tracer for molecular clouds.

  11. INTRODUCTION Information on the abundance of large whales in Greenland

    E-Print Network [OSTI]

    Laidre, Kristin L.

    INTRODUCTION Information on the abundance of large whales in Greenland waters, including fin whales surveys were conducted in West Greenland by the Greenland Fisheries Research Institute (m/v Regina Maris when survey conditions are optimal in Greenlandic waters. Between 1983 and 1993, visual aerial surveys

  12. abundance bed net: Topics by E-print Network

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

    abundance bed net First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Open Access Impact of...

  13. Carbon Abundances in the Galactic Thin and Thick Disks

    E-Print Network [OSTI]

    T. Bensby; S. Feltzing

    2005-06-07T23:59:59.000Z

    Although carbon is, together with oxygen and nitrogen, one of the most important elements in the study of galactic chemical evolution its production sites are still poorly known and have been much debated (see e.g. Gustafsson et al. 1999; Chiappini et al. 2003). To trace the origin and evolution of carbon we have determined carbon abundances from the forbidden [C I] line at 8727 A and made comparisons to oxygen abundances from the forbidden [O I] line at 6300 A in a sample of 51 nearby F and G dwarf stars. These data and the fact that the forbidden [C I] and [O I] lines are very robust abundance indicators (they are essentially insensitive to deviations from LTE and uncertainties in the stellar parameters, see, e.g., Gustafsson et al. 1999; Asplund et al. 2005) enable us to very accurately measure the C/O ratio as well as individual C and O abundances. Our first results indicate that the time-scale for the main source that contribute to the carbon enrichment of the interstellar medium operate on the same time-scale as those that contribute to the iron enrichment (and can possibly be AGB stars...)

  14. Zirconium, barium, lanthanum, and europium abundances in open clusters

    E-Print Network [OSTI]

    Friel, Eileen D.

    We present an analysis of the s-process elements Zr, Ba, and La and the r-process element Eu in a sample of 50 stars in 19 open clusters. Stellar abundances of each element are based on measures of a minimum of two lines ...

  15. Initiation of nuclear reactions under laser irradiation of Au nanoparticles in the aqueous solution of Uranium salt

    E-Print Network [OSTI]

    A. V. Simakin; G. A. Shafeev

    2009-11-29T23:59:59.000Z

    Laser exposure of suspension of either gold or palladium nanoparticles in aqueous solutions of UO2Cl2 of natural isotope abundance was experimentally studied. Picosecond Nd:YAG lasers at peak power from 1011 to 1013 W/cm2 at the wavelength of 1064 and 355 nm were used as well as a visible-range Cu vapor laser at peak power of 1010 W/cm2. The composition of colloidal solutions before and after laser exposure was analyzed using atomic absorption and gamma spectroscopy between 0.06 and 1 MeV range of photon energy. A real-time gamma-spectroscopy was used to characterize the kinetics of nuclear reactions during laser exposure. It was found that laser exposure initiated nuclear reactions involving both 238U and 235U nuclei via different channels in H2O and D2O. The influence of saturation of both the liquid and nanoparticles by gaseous H2 and D2 on the kinetics of nuclear transformations was found. Possible mechanisms of observed processes are discussed.

  16. Solution dewatering with concomitant ion removal

    DOE Patents [OSTI]

    Peterson, Eric S.; Marshall, Douglas W.; Stone, Mark L.

    2003-08-05T23:59:59.000Z

    One of the biggest needs in the separations and waste handling and reduction area is a method for dewatering ion-containing solutions. Unexpectedly, it has been found that phosphazene polymers can discriminate between water and metal ions, allowing water to pass through the membrane while retaining the ions. This unexpected result, along with the inherent chemical and thermal stability of the phosphazene polymers, yields a powerful tool for separating and dewatering metal-ion-containing solutions.

  17. Combined Heat and Power (CHP) Installation Market to be Driven by Abundant

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof EnergyInnovationin UrbanCityCoated ConductorsColonialComanche Clean Energy

  18. ZIRCONIUM, BARIUM, LANTHANUM, AND EUROPIUM ABUNDANCES IN OPEN CLUSTERS

    SciTech Connect (OSTI)

    Jacobson, Heather R. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48823 (United States); Friel, Eileen D., E-mail: jacob189@msu.edu, E-mail: efriel@indiana.edu, E-mail: hrj@mit.edu [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States)

    2013-04-15T23:59:59.000Z

    We present an analysis of the s-process elements Zr, Ba, and La and the r-process element Eu in a sample of 50 stars in 19 open clusters. Stellar abundances of each element are based on measures of a minimum of two lines per species via both equivalent width and spectrum synthesis techniques. We investigate cluster mean neutron-capture abundance trends as a function of cluster age and location in the Milky Way disk and compare them to results found in other studies in the literature. We find a statistically significant trend of increasing cluster [Ba/Fe] as a function of decreasing cluster age, in agreement with recent findings for other open cluster samples, supporting the increased importance of low-mass asymptotic giant branch stars to the generation of s-process elements. However, the other s-process elements, [La/Fe] and [Zr/Fe], do not show similar dependences, in contrast to theoretical expectations and the limited observational data from other studies. Conversely, cluster [Eu/Fe] ratios show a slight increase with increasing cluster age, although with marginal statistical significance. Ratios of [s/r]-process abundances, [Ba/Eu] and [La/Eu], however, show more clearly the increasing efficiency of s-process relative to r-process enrichment in open cluster chemical evolution, with significant increases among younger clusters. Last, cluster neutron-capture element abundances appear to be independent of Galactocentric distance. We conclude that a homogeneous analysis of a larger sample of open clusters is needed to resolve the apparent discrepant conclusions between different studies regarding s-process element abundance trends with age to better inform models of galactic chemical evolution.

  19. History of Milky Way Dwarf Spheroidal Galaxies Imprinted on Abundance Patterns of Neutron-Capture Elements

    E-Print Network [OSTI]

    Takuji Tsujimoto; Toshikazu Shigeyama

    2002-05-02T23:59:59.000Z

    Stellar abundance pattern of neutron-capture elements such as barium is used as a powerful tool to infer how star formation proceeded in dwarf spheroidal (dSph) galaxies. It is found that the abundance correlation of barium with iron in stars belonging to dSph galaxies orbiting the Milky Way, i.e., Draco, Sextans, and Ursa Minor have a feature similar to the barium-iron correlation in Galactic metal-poor stars. The common feature of these two correlations can be realized by our inhomogeneous chemical evolution model based on the supernova-driven star formation scenario if dSph stars formed from gas with a velocity dispersion of ~26 km/s. This velocity dispersion together with the stellar luminosities strongly suggest that dark matter dominated dSph galaxies. The tidal force of the Milky Way links this velocity dispersion with the currently observed value <10 km/s by stripping the dark matter in dSph galaxies. As a result, the total mass of each dSph galaxy is found to have been originally ~25 times larger than at present. Our inhomogeneous chemical evolution model succeeds in reproducing the stellar [Fe/H] distribution function observed in Sextans. In this model, supernovae immediately after the end of the star formation epoch can expel the remaining gas over the gravitational potential of the dSph galaxy.

  20. Contracts for dispatchable power

    SciTech Connect (OSTI)

    Kahn, E.P.; Stoft, S.; Marnay, C.; Berman, D.

    1990-10-01T23:59:59.000Z

    Competitive bidding for electric power is maturing. Increasing numbers of utilities are soliciting proposals from private suppliers. The amount of capacity being sought is increasing, and potential suppliers appear to be abundant. Analysis of these developments still remains limited. Evidence on the behavior of this market is scarce and sketchy. The underlying economic principles that are shaping the market have not clearly been articulated. In this report we examine the economics of competitive bidding both empirically and analytically. Previous study of this market has focused on the evaluation criteria specified in Requests for Proposals (RFPs), and highly aggregated summary statistics on participation and results. We continue the examination of RFPs, but also survey the details of long term contracts that have emerged from competitive bidding. Contracts provide a new level of specific detail that has not been previously available. 68 refs., 13 figs., 25 tabs.

  1. Fissile solution dynamics: Student research

    SciTech Connect (OSTI)

    Hetrick, D.L.

    1994-09-01T23:59:59.000Z

    There are two research projects in criticality safety at the University of Arizona: one in dynamic simulation of hypothetical criticality accidents in fissile solutions, and one in criticality benchmarks using transport theory. We have used the data from nuclear excursions in KEWB, CRAC, and SILENE to help in building models for solution excursions. An equation of state for liquids containing gas bubbles has been developed and coupled to point-reactor dynamics in an attempt to predict fission rate, yield, pressure, and kinetic energy. It appears that radiolytic gas is unimportant until after the first peak, but that it does strongly affect the shape of the subsequent power decrease and also the dynamic pressure.

  2. Geometry of Power Flows and Optimization in Distribution Networks Javad Lavaei, David Tse and Baosen Zhang

    E-Print Network [OSTI]

    Lavaei, Javad

    of the solution of the power flow problem, and (ii) the non-negativity of the locational marginal prices. Partial

  3. X-ray Absorption Spectroscopy of the Multi-phase Interstellar Medium: Oxygen and Neon Abundances

    E-Print Network [OSTI]

    Yangsen Yao; Q. Daniel Wang

    2005-12-19T23:59:59.000Z

    X-ray absorption spectroscopy provides a potentially powerful tool in determining the metal abundances in various phases of the interstellar medium (ISM). We present a case study of the sight line toward 4U 1820-303 (Galactic coordinates l, b=2.79, -7.91 and distance = 7.6 kpc), based on Chandra Grating observations. The detection of OI, OII, OIII, OVII, OVIII, and NeIX Kalpha absorption lines allows us to measure the atomic column densities of the neutral, warm ionized, and hot phases of the ISM through much of the Galactic disk. By comparing these measurements with the 21 cm hydrogen emission and with the pulsar dispersion measure along the same sight line, we estimate the mean oxygen abundances in the neutral and total ionized phases as 0.3(0.2, 0.6) and 2.2(1.1, 3.5) in units of Anders & Grevesse (1989) solar value. This significant oxygen abundance difference is apparently a result of molecule/dust grain destruction and recent metal enrichment in the warm ionized and hot phases. We also measure the column density of neon from its absorption edge and obtain the Ne/O ratio of the neutral plus warm ionized gas as 2.1(1.3, 3.5) solar. Accounting for the expected oxygen contained in molecules and dust grains would reduce the Ne/O ratio by a factor of ~1.5. From a joint-analysis of the OVII, OVIII, and NeIX lines, we obtain the Ne/O abundance ratio of the hot phase as 1.4(0.9, 2.1) solar, which is not sensitive to the exact temperature distribution assumed in the absorption line modeling. These comparable ISM Ne/O ratios for the hot and cooler gas are thus considerably less than the value (2.85+-0.07; 1sigma) recently inferred from corona emission of solar-like stars (Drake & Testa 2005). (abridged)

  4. Cosmological Exact Solutions in Some Modified Gravitational Theories

    E-Print Network [OSTI]

    Yousef Bisabr

    2015-04-22T23:59:59.000Z

    In a homogenous and isotropic cosmology, we introduce general exact solutions for some modified gravity models. In particular, we introduce exact solutions for power-law $f(R)$ gravity and Brans-Dicke theory in Einstein and Jordan conformal frames. In the Brans-Dicke case, the solutions are presented for both single and double exponential potentials in Einstein frame which correspond to power-law potentials in Jordan frame. Our analysis for extracting general exact solutions can also be generalized to those scalar-tensor theories in which the scalar field has an exponential coupling to Ricci scalar.

  5. Cosmological Exact Solutions in Some Modified Gravitational Theories

    E-Print Network [OSTI]

    Yousef Bisabr

    2015-05-04T23:59:59.000Z

    In a homogenous and isotropic cosmology, we introduce general exact solutions for some modified gravity models. In particular, we introduce exact solutions for power-law $f(R)$ gravity and Brans-Dicke theory in Einstein and Jordan conformal frames. In the Brans-Dicke case, the solutions are presented for both single and double exponential potentials in Einstein frame which correspond to power-law potentials in Jordan frame. Our analysis for extracting general exact solutions can also be generalized to those scalar-tensor theories in which the scalar field has an exponential coupling to Ricci scalar.

  6. Cosmological Exact Solutions in Some Modified Gravitational Theories

    E-Print Network [OSTI]

    Bisabr, Yousef

    2015-01-01T23:59:59.000Z

    In a homogenous and isotropic cosmology, we introduce general exact solutions for some modified gravity models. In particular, we introduce exact solutions for power-law $f(R)$ gravity and Brans-Dicke theory in Einstein and Jordan conformal frames. In the Brans-Dicke case, the solutions are presented for both single and double exponential potentials in Einstein frame which correspond to power-law potentials in Jordan frame. Our analysis for extracting general exact solutions can also be generalized to those scalar-tensor theories in which the scalar field has an exponential coupling to Ricci scalar.

  7. Powerit Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation,Pillar Group BV Jump to: navigation,Power Rental Market Place:Powerit Solutions

  8. Line temperatures and elemental abundances in HII galaxies

    E-Print Network [OSTI]

    Enrique Perez-Montero; Angeles I. Diaz

    2003-09-02T23:59:59.000Z

    We present long-slit spectrophotometric observations in the red and near infrared of 12 HII galaxies. The spectral range includes the sulphur lines [SII] at wavelengths 6716, 6731 angstroms and [SIII] at 6312 angstroms and 9069, 9532 angstroms. For all of the observed galaxies, at least three ion-weighted temperatures from forbidden auroral to nebular line ratios have been obtained and the relations between the different line temperatures have been discussed. It is found that, for some objects, the [OII] temperatures derived from those of [OIII] through the use of photo-ionisation models, without taking into account the effect of density, can lead to a significant underestimate of the O+/H+ ionic abundance and hence of the total oxygen abundance.

  9. Beryllium abundance in turn-off stars of NGC 6752

    E-Print Network [OSTI]

    Luca Pasquini; Piercarlo Bonifacio; Sofia Randich; Daniele Galli; Raffaele G. Gratton; B. Wolff

    2006-12-27T23:59:59.000Z

    Aims: To measure the beryllium abundance in two TO stars of the Globular Cluster NGC 6752, one oxygen rich and sodium poor, the other presumably oxygen poor and sodium rich. Be abundances in these stars are used to put on firmer grounds the hypothesis of Be as cosmochronometer and to investigate the formation of Globular Clusters. Method:We present near UV spectra with resolution R$\\sim 45000$ obtained with the UVES spectrograph on the 8.2m VLT Kueyen telescope, analysed with spectrum synthesis based on plane parallel LTE model atmospheres. Results:Be is detected in the O rich star with log(Be/H)=-12.04 $\\pm$0.15, while Be is not detected in the other star for which we obtain the upper limit log(Be/H)$<$-12.2. A large difference in nitrogen abundance (1.6 dex) is found between the two stars. Conclusions:The Be measurement is compatible with what found in field stars with the same [Fe/H] and [O/H]. The 'Be age' of the cluster is found to be 13.3 Gyrs, in excellent agreement with the results from main sequence fitting and stellar evolution. The presence of Be confirms the results previously obtained for the cluster NGC 6397 and supports the hypothesis that Be can be used as a clock for the early formation of the Galaxy. Since only an upper limit is found for the star with low oxygen abundance, we cannot decide between competing scenarios of Globular Cluster formation, but we can exclude that 'polluted' stars are substantially younger than 'unpolluted' ones. We stress that the Be test might be the only measurement capable of distinguishing between these scenarios.

  10. Distribution and Abundance Patterns of Spiders Inhabiting Cotton in Texas.

    E-Print Network [OSTI]

    Dean, D.A.; Sterling, W.L.

    1987-01-01T23:59:59.000Z

    . L. Sterling Department of Entomology Texas A&M University Abstract Patterns of the distribution and abundance of spiders were determined in the major cotton growing areas of Texas during 1982-83. M isumenops spp., Oxyopes saiticus Hentz... to predict this neutrality is important since spiders could then be eliminated as an important factor in predicting the dynamics of other arthropods. The cotton fleahopper (Pseudatomoscelis seriatus [Reuter]) model (Hartstack and Sterling 1986) uses...

  11. Europium abundances in F and G disk dwarfs

    E-Print Network [OSTI]

    A. Koch; B. Edvardsson

    2001-11-06T23:59:59.000Z

    Europium abundances for 74 F and G dwarf stars of the galactic disk have been determined from the 4129.7 A Eu II line. The stars were selected from the sample of Edvardsson et al. (1993) and [Eu/Fe] shows a smaller scatter and a slightly weaker trend with [Fe/H] than found by Woolf et al. (1995). The data of the two analyses are homogenized and merged. We also discuss the adopted effective temperature scale.

  12. abundance promote coexistence: Topics by E-print Network

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

    coexistence in order to evaluate the impact interference may have on network peformance Eaton Corporation InnovationCenter. complimentary wireless solutions for connectivity....

  13. Efficient Solution of the Simplified PN Equations

    SciTech Connect (OSTI)

    Hamilton, Steven P [ORNL; Evans, Thomas M [ORNL

    2015-01-01T23:59:59.000Z

    In this paper we show new solver strategies for the multigroup SPN equations for nuclear reactor analysis. By forming the complete matrix over space, moments, and energy a robust set of solution strategies may be applied. Power iteration, shifted power iteration, Rayleigh quotient iteration, Arnoldi's method, and a generalized Davidson method, each using algebraic and physics-based multigrid preconditioners, have been compared on C5G7 MOX test problem as well as an operational PWR model. Our results show that the most ecient approach is the generalized Davidson method, that is 30{40 times faster than traditional power iteration and 6{10 times faster than Arnoldi's method.

  14. CHAOS II: Gas-Phase Abundances in NGC 5194

    E-Print Network [OSTI]

    Croxall, Kevin V; Berg, Danielle; Skillman, Evan D; Moustakas, John

    2015-01-01T23:59:59.000Z

    We have observed NGC5194 (M51a) as part of the CHemical Abundances of Spirals (CHAOS) project. Using the Multi Object Double Spectrographs (MODS) on the Large Binocular Telescope (LBT) we are able to measure one or more of the temperature-sensitive auroral lines ([O III] 4363, [N II] 5755, [S III] 6312) and thus measure "direct" gas-phase abundances in 29 individual HII regions. [O III] 4363 is only detected in two HII regions both of which show indications of excitation by shocks. We compare our data to previous direct abundances measured in NGC5194 and find excellent agreement for all but one region (Delta[log(O/H)] ~ 0.04). We find no evidence of trends in Ar/O, Ne/O, or S/O within NGC5194 or compared to other galaxies. We find modest negative gradients in both O/H and N/O with very little scatter (sigma = -0.62) suggests secondary nitrogen production is responsible for a significantly larger fraction of nitrogen (e.g., factor of 8-10) relative to primary production mechanisms than predicted by theoretica...

  15. Lithium abundance in a sample of solar-like stars

    E-Print Network [OSTI]

    López-Valdivia, R; Bertone, E; Chávez, M; de Miera, F Cruz-Saenz; Amazo-Gómez, E M

    2015-01-01T23:59:59.000Z

    We report on the determination of the lithium abundance [A(Li)] of 52 solar-like stars. For 41 objects the A(Li) here presented corresponds to the first measurement. We have measured the equivalent widths of the 6708\\AA\\ lithium feature in high-resolution spectroscopic images ($R \\sim 80\\,000$), obtained at the Observatorio Astrof\\'isico Guillermo Haro (Sonora, Mexico), as part of the first scientific observations of the revitalized Lunar and Planetary Laboratory (LPL) Echelle Spectrograph, now known as the Cananea High-resolution Spectrograph (CanHiS). Lithium abundances were derived with the Fortran code MOOG, using as fundamental input a set of atmospheric parameters recently obtained by our group. With the help of an additional small sample with previous A(Li) determinations, we demonstrate that our lithium abundances are in agreement, to within uncertainties, with other works. Two target objects stand out from the rest of the sample. The star BD+47 3218 ($T_{\\rm eff}$ = 6050$\\pm$52 K, A(Li) = 1.86$\\pm$ 0...

  16. Oxygen abundance methods in the SDSS: view from modern statistics

    E-Print Network [OSTI]

    F. Shi; G. Zhao; James Wicker

    2007-10-24T23:59:59.000Z

    Our purpose is to find which is the most reliable one among various oxygen abundance determination methods. We will test the validity of several different oxygen abundance determination methods using methods of modern statistics. These methods include Bayesian analysis and information scoring. We will analyze a sample of $\\sim$6000 $\\hii$ galaxies from the Sloan Digital Sky Survey (SDSS) spectroscopic observations data release four. All methods that we used drew the same conclusion that the $T_e$ method is a more reliable oxygen abundance determination methods than the Bayesian metallcity method under the existing telescope ability. The ratios of the likelihoods between the different kinds of methods tell us that the $T_e$, $P$, and $O3N2$ methods are consistent with each other because the $P$ and $O3N2$ method are calibrated by $T_e$-method. The Bayesian and $R_{23}$ method are consistent with each other because both are calibrated by a galaxy model. In either case, the $N2$ method is an {\\it unreliable} method.

  17. CHEMICAL ABUNDANCE PATTERNS AND THE EARLY ENVIRONMENT OF DWARF GALAXIES

    SciTech Connect (OSTI)

    Corlies, Lauren; Johnston, Kathryn V.; Bryan, Greg [Department of Astronomy, Columbia University, New York, NY 10027 (United States); Tumlinson, Jason [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD (United States)

    2013-08-20T23:59:59.000Z

    Recent observations suggest that abundance pattern differences exist between low metallicity stars in the Milky Way stellar halo and those in the dwarf satellite galaxies. This paper takes a first look at what role the early environment for pre-galactic star formation might have played in shaping these stellar populations. In particular, we consider whether differences in cross-pollution between the progenitors of the stellar halo and the satellites could help to explain the differences in abundance patterns. Using an N-body simulation, we find that the progenitor halos of the main halo are primarily clustered together at z = 10 while the progenitors of the satellite galaxies remain on the outskirts of this cluster. Next, analytically modeled supernova-driven winds show that main halo progenitors cross-pollute each other more effectively while satellite galaxy progenitors remain more isolated. Thus, inhomogeneous cross-pollution as a result of different high-z spatial locations of each system's progenitors can help to explain observed differences in abundance patterns today. Conversely, these differences are a signature of the inhomogeneity of metal enrichment at early times.

  18. Application of solar-powered desalination in a remote town in South Australia 

    E-Print Network [OSTI]

    De Munari, Annalisa; Capão, D.P.S; Richards, B.S.; Schäfer, Andrea

    2009-01-01T23:59:59.000Z

    Coober Pedy is a remote town in South Australia with abundant solar radiation and scarce and low quality water, where a reverse osmosis plant has been operating since 1967. This paper evaluates the feasibility of powering ...

  19. Power Capture (PowCap) Board for Non Intrusive Load Monitoring and Power Line Communication Exploration and Development

    E-Print Network [OSTI]

    Balakrishnan, Vikram

    2013-01-01T23:59:59.000Z

    PowCap with PLC: Lookingti] “Power Line Communication (PLC) Solutions. ” http://overview.page? DCMP=plc&HQS=plc. [Tsu99] K. Tsuda. “Subspace

  20. Nuclear Power

    E-Print Network [OSTI]

    Vilhena and Bardo E.J. Bodmann Carbon-#1;? in Terrestrial and Aquatic Environment of Ignalina Nuclear Power Plant: Sources of Production, Releases and Dose Estimates #3;?? Jonas Mazeika Impact of radionuclide discharges from Temel?n Nuclear Power... (chapter 5), ? Instrumentation and control (chapter 6), ? Diagnostics (chapter 7), ? Safety evaluation methods (chapters 6, 8, 9 and 10), ? Environment and nuclear power plants (chapters 11 - 15), ? Human factors (chapter 16), ? Software development...

  1. Power LCAT

    ScienceCinema (OSTI)

    Drennen, Thomas

    2014-06-27T23:59:59.000Z

    POWER LCAT is a software tool used to compare elements of efficiency, cost, and environmental effects between different sources of energy.

  2. Power LCAT

    SciTech Connect (OSTI)

    Drennen, Thomas

    2012-08-15T23:59:59.000Z

    POWER LCAT is a software tool used to compare elements of efficiency, cost, and environmental effects between different sources of energy.

  3. American Power: Proposed Penalty (2010-CE-0911)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that American Power Solutions, Inc. failed to certify a general service fluorescent lamp as compliant with the applicable energy conservation standards.

  4. A Survey of Architectural Techniques For Improving Cache Power Efficiency

    E-Print Network [OSTI]

    , there has been a significant increase in their leakage energy consumption. For this reason, cache power to invent novel solutions for enabling low- power operation of caches. Index Terms--Cache energy saving techniques, architectural techniques, dynamic energy, leakage energy, power management, low-power, energy

  5. Region-Specific Protein Abundance Changes in the Brain of MPTP...

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

    Region-Specific Protein Abundance Changes in the Brain of MPTP-induced Parkinson’s Disease Mouse Model . Region-Specific Protein Abundance Changes in the Brain of...

  6. The Water Abundance of the Directly Imaged Substellar Companion {\\kappa} And b Retrieved from a Near Infrared Spectrum

    E-Print Network [OSTI]

    Todorov, Kamen O; Pineda, Jaime E; Meyer, Michael R; Quanz, Sascha P; Hinkley, Sasha; Fortney, Jonathan J

    2015-01-01T23:59:59.000Z

    Recently, spectral retrieval has proven to be a powerful tool for constraining the physical properties and atmospheric compositions of extrasolar planet atmospheres from observed spectra, primarily for transiting objects but also increasingly for directly imaged planets and brown dwarfs. Despite its strengths, this approach has been applied to only about a dozen targets. Determining the abundances of the main carbon and oxygen-bearing compounds in a planetary atmosphere can lead to the C/O ratio of the object, which is crucial in understanding its formation and migration history. We present a retrieval analysis on the published near-infrared spectrum of {\\kappa} And b, a directly imaged substellar companion to a young B9 star. We fit the emission spectrum model utilizing a Markov Chain Monte Carlo algorithm. We estimate the abundance of water vapor, and its uncertainty, in the atmosphere of the object. We also place upper limits on the abundances of carbon dioxide and methane and constrain the pressure-temper...

  7. Remarkable Amphibian Biomass and Abundance in an Isolated Wetland: Implications for Wetland

    E-Print Network [OSTI]

    Georgia, University of

    -1739.2006.00443.x #12;1458 Amphibian Biomass and Abundance Gibbons et al. Biomasa y Abundancia de Anfibios

  8. RUBIDIUM ABUNDANCES IN THE GLOBULAR CLUSTERS NGC 6752, NGC 1904, AND NGC 104 (47 Tuc)

    SciTech Connect (OSTI)

    D'Orazi, Valentina [Department of Physics and Astronomy, Macquarie University, Balaclava Road, North Ryde, NSW 2109 (Australia); Lugaro, Maria; Campbell, Simon W. [Monash Centre for Astrophysics, School of Mathematical Sciences, Monash University, Building 28, Clayton, VIC 3800 (Australia); Bragaglia, Angela; Carretta, Eugenio [INAF Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna (Italy); Gratton, Raffaele G.; Lucatello, Sara [INAF Osservatorio Astronomico di Padova, vicolo dell'Osservatorio 5, I-35122 Padova (Italy); D'Antona, Francesca, E-mail: valentina.dorazi@mq.edu.au [INAF Osservatorio Astronomico di Roma, via Frascati 33, I-00040 Monteporzio (Italy)

    2013-10-10T23:59:59.000Z

    Large star-to-star variations of the abundances of proton-capture elements, such as Na and O, in globular clusters (GCs) are interpreted as the effect of internal pollution resulting from the presence of multiple stellar populations. To better constrain this scenario, we investigate the abundance distribution of the heavy element rubidium (Rb) in NGC 6752, NGC 1904, and NGC 104 (47 Tuc). Combining the results from our sample with those in the literature, we found that Rb exhibits no star-to-star variations, regardless of cluster metallicity, with the possible intriguing, although very uncertain, exception of the metal-rich bulge cluster NGC 6388. If no star-to-star variations can be confirmed for all GCs, this finding implies that the stellar source of the proton-capture element variations must not have produced significant amounts of Rb. This element is observed to be enhanced at extremely high levels in intermediate-mass asymptotic giant branch (IM-AGB) stars in the Magellanic Clouds (i.e., at a metallicity similar to 47 Tuc and NGC 6388). This fact may present a challenge to this popular candidate polluter, unless the mass range of the observed IM-AGB stars does not participate in the formation of the second-generation stars in GCs. A number of possible solutions are available to resolve this conundrum, including the fact that the Magellanic Cloud observations are very uncertain and may need to be revised. The fast rotating massive stars scenario would not face this potential problem as the slow mechanical winds of these stars during their main-sequence phase do not carry any Rb enhancements; however, these candidates face even bigger issues such as the production of Li and the close overlap with core-collapse supernova timescales. Observations of Sr, Rb, and Zr in metal-rich clusters such as NGC 6388 and NGC 6441 are sorely needed to clarify the situation.

  9. DIVERSITY OF TYPE Ia SUPERNOVAE IMPRINTED IN CHEMICAL ABUNDANCES

    SciTech Connect (OSTI)

    Tsujimoto, Takuji [National Astronomical Observatory of Japan, Mitaka-shi, Tokyo 181-8588 (Japan); Shigeyama, Toshikazu, E-mail: taku.tsujimoto@nao.ac.jp [Research Center for the Early Universe, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2012-12-01T23:59:59.000Z

    A time delay of Type Ia supernova (SN Ia) explosions hinders the imprint of their nucleosynthesis on stellar abundances. However, some occasional cases give birth to stars that avoid enrichment of their chemical compositions by massive stars and thereby exhibit an SN-Ia-like elemental feature including a very low [Mg/Fe] ( Almost-Equal-To - 1). We highlight the elemental feature of Fe-group elements for two low-Mg/Fe objects detected in nearby galaxies, and propose the presence of a class of SNe Ia that yield the low abundance ratios of [Cr, Mn, Ni/Fe]. Our novel models of chemical evolution reveal that our proposed class of SNe Ia (slow SNe Ia) is associated with ones exploding on a long timescale after their stellar birth and give a significant impact on the chemical enrichment in the Large Magellanic Cloud (LMC). In the Galaxy, on the other hand, this effect is unseen due to the overwhelming enrichment by the major class of SNe Ia that explode promptly (prompt SNe Ia) and eject a large amount of Fe-group elements. This nicely explains the different [Cr, Mn, Ni/Fe] features between the two galaxies as well as the puzzling feature seen in the LMC stars exhibiting very low Ca but normal Mg abundances. Furthermore, the corresponding channel of slow SN Ia is exemplified by performing detailed nucleosynthesis calculations in the scheme of SNe Ia resulting from a 0.8 + 0.6 M{sub Sun} white dwarf merger.

  10. Abundances of metal-weak thick-disc candidates

    E-Print Network [OSTI]

    P. Bonifacio; M. Centurion; P. Molaro

    1999-06-03T23:59:59.000Z

    High resolution spectra of 5 candidate metal-weak thick-disc stars suggested by Beers & Sommer-Larsen (1995) are analyzed to determine their chemical abundances. The low abundance of all the objects has been confirmed with metallicity reaching [Fe/H]=-2.9. However, for three objects, the astrometric data from the Hipparcos catalogue suggests they are true halo members. The remaining two, for which proper-motion data are not available, may have disc-like kinematics. It is therefore clear that it is useful to address properties of putative metal-weak thick-disc stars only if they possess full kinematic data. For CS 22894-19 the abundance pattern similar to those of typical halo stars is found, suggesting that chemical composition is not a useful discriminant between thick-disc and halo stars. CS 29529-12 is found to be C enhanced with [C/Fe]=+1.0; other chemical peculiarities involve the s process elements: [Sr/Fe]=-0.65 and [Ba/Fe]=+0.62, leading to a high [Ba/Sr] considerably larger than what is found in more metal-rich carbon-rich stars, but similar to LP 706-7 and LP 625-44 discussed by Norris et al (1997a). Hipparcos data have been used to calculate the space velocities of 25 candidate metal-weak thick-disc stars, thus allowing us to identify 3 bona fide members, which support the existence of a metal-poor tail of the thick-disc, at variance with a claim to the contrary by Ryan & Lambert (1995).

  11. MANGANESE ABUNDANCES IN THE GLOBULAR CLUSTER {omega} CENTAURI

    SciTech Connect (OSTI)

    Cunha, Katia; Smith, Verne V. [National Optical Astronomy Observatory, 950 N. Cherry Avenue, Tucson, AZ, 85719 (United States); Bergemann, Maria [Max-Planck Institute for Astrophysics, Karl-Schwarzschild Str. 1, 85741 Garching (Germany); Suntzeff, Nicholas B. [Department of Physics and Astronomy and Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States); Lambert, David L. [University of Texas, 1 University Station, C1400, Austin, TX 78712 (United States)

    2010-07-01T23:59:59.000Z

    We present manganese abundances in 10 red giant members of the globular cluster {omega} Centauri; eight stars are from the most metal-poor population (RGB MP and RGB MInt1) while two targets are members of the more metal-rich groups (RGB MInt2 and MInt3). This is the first time Mn abundances have been studied in this peculiar stellar system. The LTE values of [Mn/Fe] in {omega} Cen overlap those of Milky Way stars in the metal-poor {omega} Cen populations ([Fe/H] {approx}-1.5 to -1.8), however unlike what is observed in Milky Way halo and disk stars, [Mn/Fe] declines in the two more metal-rich RGB MInt2 and MInt3 targets. Non-LTE calculations were carried out in order to derive corrections to the LTE Mn abundances. The non-LTE results for {omega} Cen in comparison with the non-LTE [Mn/Fe] versus [Fe/H] trend obtained for the Milky Way confirm and strengthen the conclusion that the manganese behavior in {omega} Cen is distinct. These results suggest that low-metallicity supernovae (with metallicities {<=} -2) of either Type II or Type Ia dominated the enrichment of the more metal-rich stars in {omega} Cen. The dominance of low-metallicity stars in the chemical evolution of {omega} Cen has been noted previously in the s-process elements where enrichment from metal-poor asymptotic giant branch stars is indicated. In addition, copper, which also has metallicity-dependent yields, exhibits lower values of [Cu/Fe] in the RGB MInt2 and MInt3 {omega} Cen populations.

  12. A Novel Power Flow Method for Long Term Frequency Stability Analysis 

    E-Print Network [OSTI]

    Yan, Wenjin

    2013-05-06T23:59:59.000Z

    This thesis presents a novel approach for a power system to find a practical power flow solution when all the generators in the system have hit their real power output limits, such as some generator units shutting down or ...

  13. Power management is important for multicore architectures. One important challenge for multicore

    E-Print Network [OSTI]

    Sorin, Daniel J.

    1 Abstract Power management is important for multicore architectures. One important challenge difficulty varies among designs, depending, for example, on the particular power management mechanisms systems motivate the development and evaluation of efficient power manage- ment solutions targeted

  14. Renewable Energy Powered Membrane Technology. 1. Development and Characterization of a Photovoltaic Hybrid Membrane System 

    E-Print Network [OSTI]

    Schäfer, Andrea; Broeckmann, Andreas; Richards, Bryce

    2007-01-01T23:59:59.000Z

    the unavailability of power in many such situations, renewable energy is an obvious solution to power such systems. However, renewable energy is an intermittent power supply and with regards to the performance of intermittently operated desalination systems, only...

  15. Abundance profile and stellar content of IZw18

    E-Print Network [OSTI]

    F. Legrand

    1997-12-08T23:59:59.000Z

    New spectroscopic observations of the metal poor galaxy IZw 18 are discussed. Wolf-Rayet stars of WC type have been detected in the NW-HII region contrary to evolutionary synthesis model predictions. Implications on the mass loss rate and on the formation processes of WR stars are discussed. A very homogeneous metal abundance is observed within the HII region. This emphasizes the problem of the dispersal and mixing of new synthesized element in a starburst. Different scenarios are discussed, showing that metals remain most likely hidden in a hot phase and that the observed present metallicity is the result of a previous star formation event.

  16. Non-LTE Abundances of Magnesium, Aluminum and Sulfur in OB Stars Near the Solar Circle

    E-Print Network [OSTI]

    S. Daflon; K. Cunha; V. V. Smith; K. Butler

    2002-12-09T23:59:59.000Z

    Non-LTE abundances of magnesium, aluminum and sulfur are derived for a sample of 23 low-v \\sin i stars belonging to six northern OB associations of the Galactic disk within 1 kpc of the Sun. The abundances are obtained from the fitting of synthetic line profiles to high resolution spectra. A comparison of our results with HII region abundances indicates good agreement for sulfur while the cepheid abundances are higher. The derived abundances of Mg show good overlap with the cepheid results. The aluminum abundances for OB stars are significantly below the cepheid values. But, the OB star results show a dependence with effective temperature and need further investigation. The high Al abundances in the cepheids could be the result of mixing. A discussion of the oxygen abundance in objects near the solar circle suggests that the current mean galactic oxygen abundance in this region is 8.6-8.7 and in agreement with the recently revised oxygen abundance in the solar photosphere. Meaningful comparisons of the absolute S, Al and Mg abundances in OB stars with the Sun must await a reinvestigation of these elements, as well as the meteoritic reference element Si, with 3D hydrodynamical model atmospheres for the Sun. No abundance gradients are found within the limited range in galactocentric distances in the present study. Such variations would be expected only if there were large metallicity gradients in the disk.

  17. Abundances of Vanadium and Bromine in 3 Cen A: Additional Odd-Z Anomalies

    E-Print Network [OSTI]

    C. R. Cowley; G. M. Wahlgren

    2005-12-12T23:59:59.000Z

    We report abundance excesses of 1.2 and 2.6 dex, respectively, for vanadium and bromine in the hot, peculiar star 3 Cen A. Abundances for these two odd-Z elements have not been previously reported for this star. Taken with previous work, they strengthen the case of the origin of the abundance peculiarities by diffusion.

  18. OXYGEN GAS-PHASE ABUNDANCE REVISITED M. K. Andre,1,2

    E-Print Network [OSTI]

    Howk, Jay Christopher

    OXYGEN GAS-PHASE ABUNDANCE REVISITED M. K. Andre´,1,2 C. M. Oliveira,2 J. C. Howk,2 R. Ferlet,1 J gas-phase oxygen abundance along the sight lines toward 19 early-type Galactic stars at an average magÀ1 with a standard deviation of 15% is consistent with previous surveys. The mean oxygen abundance

  19. Regional Transmission Projects: Finding Solutions

    SciTech Connect (OSTI)

    The Keystone Center

    2005-06-15T23:59:59.000Z

    The Keystone Center convened and facilitated a year-long Dialogue on "Regional Transmission Projects: Finding Solutions" to develop recommendations that will help address the difficult and contentious issues related to expansions of regional electric transmission systems that are needed for reliable and economic transmission of power within and across regions. This effort brought together a cross-section of affected stakeholders and thought leaders to address the problem with the collective wisdom of their experience and interests. Transmission owners sat at the table with consumer advocates and environmental organizations. Representatives from regional transmission organizations exchanged ideas with state and federal regulators. Generation developers explored common interests with public power suppliers. Together, the Dialogue participants developed consensus solutions about how to begin unraveling some of the more intractable issues surrounding identification of need, allocation of costs, and reaching consensus on siting issues that can frustrate the development of regional transmission infrastructure. The recommendations fall into three broad categories: 1. Recommendations on appropriate institutional arrangements and processes for achieving regional consensus on the need for new or expanded transmission infrastructure 2. Recommendations on the process for siting of transmission lines 3. Recommendations on the tools needed to support regional planning, cost allocation, and siting efforts. List of Dialogue participants: List of Dialogue Participants: American Electric Power American Transmission Company American Wind Energy Association California ISO Calpine Corporation Cinergy Edison Electric Institute Environmental Defense Federal Energy Regulatory Commission Great River Energy International Transmission Company ISO-New England Iowa Public Utility Board Kanner & Associates Midwest ISO National Association of Regulatory Utility Commissioners National Association of State Utility Consumer Advocates National Grid Northeast Utilities PA Office of Consumer Advocates Pacific Gas & Electric Corporation Pennsylvania Public Utility Commission PJM Interconnection The Electricity Consumers Resource Council U.S. Department of Energy US Department of the Interior Van Ness Feldman Western Interstate Energy Board Wind on the Wires Wisconsin Public Service Commission Xcel Energy

  20. Power system

    DOE Patents [OSTI]

    Hickam, Christopher Dale (Glasford, IL)

    2008-03-18T23:59:59.000Z

    A power system includes a prime mover, a transmission, and a fluid coupler having a selectively engageable lockup clutch. The fluid coupler may be drivingly connected between the prime mover and the transmission. Additionally, the power system may include a motor/generator drivingly connected to at least one of the prime mover and the transmission. The power-system may also include power-system controls configured to execute a control method. The control method may include selecting one of a plurality of modes of operation of the power system. Additionally, the control method may include controlling the operating state of the lockup clutch dependent upon the mode of operation selected. The control method may also include controlling the operating state of the motor/generator dependent upon the mode of operation selected.

  1. Solution deposition assembly

    DOE Patents [OSTI]

    Roussillon, Yann; Scholz, Jeremy H; Shelton, Addison; Green, Geoff T; Utthachoo, Piyaphant

    2014-01-21T23:59:59.000Z

    Methods and devices are provided for improved deposition systems. In one embodiment of the present invention, a deposition system is provided for use with a solution and a substrate. The system comprises of a solution deposition apparatus; at least one heating chamber, at least one assembly for holding a solution over the substrate; and a substrate curling apparatus for curling at least one edge of the substrate to define a zone capable of containing a volume of the solution over the substrate. In another embodiment of the present invention, a deposition system for use with a substrate, the system comprising a solution deposition apparatus; at heating chamber; and at least assembly for holding solution over the substrate to allow for a depth of at least about 0.5 microns to 10 mm.

  2. Solution to Quiz 5

    E-Print Network [OSTI]

    jeffb_000

    2013-12-02T23:59:59.000Z

    Nov 19, 2013 ... Calculate the total transaction costs incurred by Patrick and Eric combined. Solution: Ask Price = 30. Bid Ask Spread = 0.50 = Ask Price - Bid ...

  3. Mixed oxide solid solutions

    DOE Patents [OSTI]

    Magno, Scott (Dublin, CA); Wang, Ruiping (Fremont, CA); Derouane, Eric (Liverpool, GB)

    2003-01-01T23:59:59.000Z

    The present invention is a mixed oxide solid solution containing a tetravalent and a pentavalent cation that can be used as a support for a metal combustion catalyst. The invention is furthermore a combustion catalyst containing the mixed oxide solid solution and a method of making the mixed oxide solid solution. The tetravalent cation is zirconium(+4), hafnium(+4) or thorium(+4). In one embodiment, the pentavalent cation is tantalum(+5), niobium(+5) or bismuth(+5). Mixed oxide solid solutions of the present invention exhibit enhanced thermal stability, maintaining relatively high surface areas at high temperatures in the presence of water vapor.

  4. Diversity of Type Ia Supernovae Imprinted in Chemical Abundances

    E-Print Network [OSTI]

    Tsujimoto, Takuji

    2012-01-01T23:59:59.000Z

    A time delay of Type Ia supernova (SN Ia) explosions hinders the imprint of their nucleosynthesis on stellar abundances. However, some occasional cases give birth to stars that avoid enrichment of their chemical compositions by massive stars and thereby exhibit a SN Ia-like elemental feature including a very low [Mg/Fe] (~-1). We highlight the elemental feature of Fe-group elements for two low-Mg/Fe objects detected in nearby galaxies, and propose the presence of a class of SNe Ia that yield the low abundance ratios of [Cr,Mn,Ni/Fe]. Our novel models of chemical evolution reveal that our proposed class of SNe Ia (slow SNe Ia) is associated with ones exploding on a long timescale after their stellar birth, and gives a significant impact on the chemical enrichment in the Large Magellanic Cloud (LMC). In the Galaxy, on the other hand, this effect is unseen due to the overwhelming enrichment by the major class of SNe Ia that explode promptly (prompt SNe Ia) and eject a large amount of Fe-group elements. This nice...

  5. Elemental Abundances from Intrinsic QSO Emission and Absorption Lines

    E-Print Network [OSTI]

    F. Hamann

    1998-06-06T23:59:59.000Z

    Several studies have shown that the column densities inferred from broad absorption lines (BALs) require extremely high metallicities and phosphorus overabundances -- apparently in conflict with other abundance diagnostics. Here I use HST spectroscopy of the BALQSO PG 1254+047 to argue that the BALs abundance estimates are incorrect, because partial line-of-sight coverage of the continuum source(s) has led to gross underestimates of the line optical depths and column densities. I claim that the significant presence of PV 1118,1128 absorption in this and other BALQSOs identifies the saturated absorption-line spectrum. This interpretation implies that the total column densities are at least ten times larger than previous estimates, namely log N_H(cm-2) > 22. The outflowing BAL gas, at velocities from -15,000 to -27,000 km/s in PG 1254+047, is therefore a strong candidate for the X-ray absorber in BALQSOs. If this high-column density outflow is radiately accelerated, it must originate <0.1 pc from the QSO.

  6. The element abundance FIP effect in the quiet Sun

    E-Print Network [OSTI]

    P. R. Young

    2005-03-02T23:59:59.000Z

    The Mg/Ne abundance ratio in the quiet Sun is measured in both network and supergranule cell centre regions through EUV spectra from the Coronal Diagnostic Spectrometer on SOHO. Twenty four sets of data over the period 1996 March to 1998 June (corresponding to solar minimum) are studied. Emission lines of the sequences Ne IV-VII and Mg V-VIII are simultaneously analysed by comparing with theoretical emissivities from the CHIANTI database to yield the Mg/Ne abundance and emission measure over the temperature region 5.0 Sun connects into the solar wind. The quiet Sun spectra are also utilised to determine the coronal density and temperature, leading to average values of 2.6^+0.5_-0.4 x 10^8 cm^-3 and log (T/K)=5.95 +/- 0.02. No significant trend with the rise in solar activity during 1996--98 is found for any of the derived quantities, implying that quiet Sun regions show little dependence on the solar cycle.

  7. Lithium abundances in exoplanet-host stars : modelling

    E-Print Network [OSTI]

    M. Castro; S. Vauclair; O. Richard; N. C. Santos

    2008-11-18T23:59:59.000Z

    Aims. Exoplanet-host stars (EHS) are known to present superficial chemical abundances different from those of stars without any detected planet (NEHS). EHS are, on the average, overmetallic compared to the Sun. The observations also show that, for cool stars, lithium is more depleted in EHS than in NEHS. The aim of this paper is to obtain constraints on possible models able to explain this difference, in the framework of overmetallic models compared to models with solar abundances. Methods. We have computed main sequence stellar models with various masses and metallicities. The results show different behaviour for the lithium destruction according to those parameters. We compare these results to the spectroscopic observations of lithium. Results. Our models show that the observed lithium differences between EHS and NEHS are not directly due to the overmetallicity of the EHS: some extra mixing is needed below the convective zones. We discuss possible explanations for the needed extra mixing, in particular an increase of the mixing efficiency associated with the development of shear instabilities below the convective zone, triggered by angular momentum transfer due to the planetary migration.

  8. HNCO abundances in galaxies: Tracing the evolutionary state of starbursts

    E-Print Network [OSTI]

    Sergio Martin; J. Martin-Pintado; R. Mauersberger

    2008-12-19T23:59:59.000Z

    The chemistry in the central regions of galaxies is expected to be strongly influenced by their nuclear activity. To find the best tracers of nuclear activity is of key importance to understand the processes taking place in the most obscured regions of galactic nuclei. In this work we present multi-line observations of CS, C34S, HNCO and C18O in a sample of 11 bright galaxies prototypical for different types of activity. The 32S/34S isotopic ratio is ~10, supporting the idea of an isotopical 34S enrichment due to massive star formation in the nuclear regions of galaxies. Although C32S and C34S do not seem to be significantly affected by the activity type, the HNCO abundance appears highly contrasted among starburst. We observed HNCO abundance variations of nearly two orders of magnitude. The HNCO molecule is shown to be a good tracer of the amount of molecular material fueling the starburst and therefore can be used as a diagnostics of the evolutionary state of a nuclear starburst.

  9. Zirconium, Barium, Lanthanum and Europium Abundances in Open Clusters

    E-Print Network [OSTI]

    Jacobson, H R; 10.1088/0004-6256/145/4/107

    2013-01-01T23:59:59.000Z

    We present an analysis of the s-process elements Zr, Ba, and La and the r-process element Eu in a sample of 50 stars in 19 open clusters. Stellar abundances of each element are based on measures of a minimum of two lines per species via both equivalent width and spectrum synthesis techniques. We investigate cluster mean neutron-capture abundance trends as a function of cluster age and location in the Milky Way disk and compare them to results found in other studies in the literature. We find a statistically significant trend of increasing cluster [Ba/Fe] as a function of decreasing cluster age, in agreement with recent findings for other open cluster samples, supporting the increased importance of low-mass asymptotic giant branch stars to the generation of s-process elements. However, the other s-process elements, [La/Fe] and [Zr/Fe], do not show similar dependences, in contrast to theoretical expectations and the limited observational data from other studies. Conversely, cluster [Eu/Fe] ratios show a slight ...

  10. Strathclyde powerS ahead

    E-Print Network [OSTI]

    Mottram, Nigel

    Strathclyde powerS ahead the future of renewable energy SHARING AND ENHANCING RESEARCH Discover the vision of Principal Professor Jim McDonald THE FUTURE OF ENERGY Strathclyde pioneers renewableEdicinE Snapshot the reSearcher Following a decade of environmental research in her native egypt, nabila saleem

  11. Nuclear Fusion: A Solution to the GlobalNuclear Fusion: A Solution to the Global Energy CrisisEnergy Crisis

    E-Print Network [OSTI]

    Strathclyde, University of

    Nuclear Fusion: A Solution to the GlobalNuclear Fusion: A Solution to the Global Energy Crisis.maclellan@strath.ac.uk Introduction and Motivation What is Nuclear Fusion? Laser Plasma Interactions The world, and particularly is harnessing the power of nuclear fusion. It is however, extremely difficult to sustain a fusion reaction

  12. Dispersant solutions for dispersing hydrocarbons

    DOE Patents [OSTI]

    Tyndall, Richard L. (Clinton, TN)

    1997-01-01T23:59:59.000Z

    A dispersant solution includes a hydrocarbon dispersing solution derived from a bacterium from ATCC 75527, ATCC 75529, or ATCC 55638.

  13. Dispersant solutions for dispersing hydrocarbons

    DOE Patents [OSTI]

    Tyndall, R.L.

    1997-03-11T23:59:59.000Z

    A dispersant solution includes a hydrocarbon dispersing solution derived from a bacterium from ATCC 75527, ATCC 75529, or ATCC 55638.

  14. Carbon stars in local group dwarf galaxies: C and O abundances

    E-Print Network [OSTI]

    R. Wahlin; K. Eriksson; B. Gustafsson; K. H. Hinkle; D. L. Lambert; N. Ryde; B. Westerlund

    2006-05-10T23:59:59.000Z

    We present abundances of carbon and oxygen as well as abundance ratios 12C/13C for a sample of carbon stars in the LMC, SMC, Carina, Sculptor and Fornax dwarf galaxies. The overall metallicities in these dwarf galaxies are lower than in the galactic disc. The observations cover most of the AGB and we discuss the abundance patterns in different regions along the AGB. The abundances are determined from infrared spectra obtained with the ISAAC spectrometer on VLT (R=1500) and the Phoenix Spectrometer on Gemini South (R=50000). The synthetic spectra used in the analysis were computed with MARCS model atmospheres. We find that the oxygen abundance is decreasing with decreasing overall metallicity of the system while the C/O ratio at a given evolutionary phase is increasing with decreasing oxygen abundance. keywords Stars: abundances -- Stars: carbon -- Stars: AGB and post-AGB -- Galaxies: dwarf -- Local Group -- Infrared: stars

  15. Power combiner

    DOE Patents [OSTI]

    Arnold, Mobius; Ives, Robert Lawrence

    2006-09-05T23:59:59.000Z

    A power combiner for the combining of symmetric and asymmetric traveling wave energy comprises a feed waveguide having an input port and a launching port, a reflector for reflecting launched wave energy, and a final waveguide for the collection and transport of launched wave energy. The power combiner has a launching port for symmetrical waves which comprises a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which comprises a sawtooth rotated about a central axis.

  16. Water reactive hydrogen fuel cell power system

    DOE Patents [OSTI]

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-01-21T23:59:59.000Z

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  17. Water reactive hydrogen fuel cell power system

    DOE Patents [OSTI]

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-11-25T23:59:59.000Z

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into the fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  18. Solvent wash solution

    DOE Patents [OSTI]

    Neace, J.C.

    1984-03-13T23:59:59.000Z

    A process is claimed for removing diluent degradation products from a solvent extraction solution, which has been used to recover uranium and plutonium from spent nuclear fuel. A wash solution and the solvent extraction solution are combined. The wash solution contains (a) water and (b) up to about, and including, 50 vol % of at least one-polar water-miscible organic solvent based on the total volume of the water and the highly-polar organic solvent. The wash solution also preferably contains at least one inorganic salt. The diluent degradation products dissolve in the highly-polar organic solvent and the organic solvent extraction solvent do not dissolve in the highly-polar organic solvent. The highly-polar organic solvent and the extraction solvent are separated.

  19. Solvent wash solution

    DOE Patents [OSTI]

    Neace, James C. (Blackville, SC)

    1986-01-01T23:59:59.000Z

    Process for removing diluent degradation products from a solvent extraction solution, which has been used to recover uranium and plutonium from spent nuclear fuel. A wash solution and the solvent extraction solution are combined. The wash solution contains (a) water and (b) up to about, and including, 50 volume percent of at least one-polar water-miscible organic solvent based on the total volume of the water and the highly-polar organic solvent. The wash solution also preferably contains at least one inorganic salt. The diluent degradation products dissolve in the highly-polar organic solvent and the organic solvent extraction solvent do not dissolve in the highly-polar organic solvent. The highly-polar organic solvent and the extraction solvent are separated.

  20. Cleco Power- Power Miser New Home Program

    Broader source: Energy.gov [DOE]

    Louisiana's Cleco Power offers energy efficiency incentives to eligible customers. Cleco Power offers a rate discount for residential customers building homes that meet the Power Miser Program...

  1. Anatomy of bubbling solutions

    E-Print Network [OSTI]

    Kostas Skenderis; Marika Taylor

    2008-05-23T23:59:59.000Z

    We present a comprehensive analysis of holography for the bubbling solutions of Lin-Lunin-Maldacena. These solutions are uniquely determined by a coloring of a 2-plane, which was argued to correspond to the phase space of free fermions. We show that in general this phase space distribution does not determine fully the 1/2 BPS state of N=4 SYM that the gravitational solution is dual to, but it does determine it enough so that vevs of all single trace 1/2 BPS operators in that state are uniquely determined to leading order in the large N limit. These are precisely the vevs encoded in the asymptotics of the LLM solutions. We extract these vevs for operators up to dimension 4 using holographic renormalization and KK holography and show exact agreement with the field theory expressions.

  2. Quiz 5 Solutions

    E-Print Network [OSTI]

    Apr 25, 2015 ... Math 373. Spring 2015. Quiz 5. April 16, 2015. 1. In a short sale of a stock, there is credit risk. Define credit risk. Solution: Credit risk is the risk ...

  3. Strategic Biomass Solutions (Mississippi)

    Broader source: Energy.gov [DOE]

    The Strategic Biomass Solutions (SBS) was formed by the Mississippi Technology Alliance in June 2009. The purpose of the SBS is to provide assistance to existing and potential companies, investors...

  4. Solution to Quiz 1

    E-Print Network [OSTI]

    jeffb_000

    2014-01-14T23:59:59.000Z

    Sep 5, 2013 ... over the next four years: Cash Flow at End of Year Amount of Cash Flow. 1. 1 Million. 2 ... project is 8%. Calculate X . Solution: By definition, the ...

  5. Solutions of Penrose's Equation

    E-Print Network [OSTI]

    E. N. Glass; Jonathan Kress

    1998-09-27T23:59:59.000Z

    The computational use of Killing potentials which satisfy Penrose's equation is discussed. Penrose's equation is presented as a conformal Killing-Yano equation and the class of possible solutions is analyzed. It is shown that solutions exist in spacetimes of Petrov type O, D or N. In the particular case of the Kerr background, it is shown that there can be no Killing potential for the axial Killing vector.

  6. Power Factor Compensation (PFC) Power Factor Compensation

    E-Print Network [OSTI]

    Knobloch,Jürgen

    Power Factor Compensation (PFC) Power Factor Compensation The power factor (PF) is defined as the ratio between the active power and the apparent power of a system. If the current and voltage are periodic with period , and [ ), then the active power is defined by ( ) ( ) (their inner product

  7. Star Power

    ScienceCinema (OSTI)

    None

    2014-11-18T23:59:59.000Z

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  8. Star Power

    SciTech Connect (OSTI)

    None

    2014-10-17T23:59:59.000Z

    The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

  9. Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample

    E-Print Network [OSTI]

    B. T. Draine; D. A. Dale; G. Bendo; K. D. Gordon; J. D. T. Smith; L. Armus; C. W. Engelbracht; G. Helou; R. C. Kennicutt; A. Li; H. Roussel; F. Walter; D. Calzetti; J. Moustakas; E. J. Murphy; G. H. Rieke; C. Bot; D. J. Hollenbach; K. Sheth; H. I. Teplitz

    2007-03-09T23:59:59.000Z

    Physical dust models are presented for 65 galaxies in the SINGS survey that are strongly detected in the four IRAC bands and three MIPS bands. For each galaxy we estimate (1) the total dust mass, (2) the fraction of the dust mass contributed by PAHs, and (3) the intensity of the starlight heating the dust grains. We find that spiral galaxies have dust properties resembling the dust in the local region of the Milky Way, with similar dust-to-gas ratio, and similar PAH abundance. The observed SEDs, including galaxies with SCUBA photometry, can be reproduced by dust models that do not require "cold" (Tmedia of galaxies with A_O=12+log(O/H)>8.1, grains contain a substantial fraction of interstellar Mg, Si and Fe. Galaxies with A_O8.1 have a median q_PAH=3.55%. The derived dust masses favor a value X_CO approx 4e20 cm^{-2}(K kms)^{-1} for the CO to H_2 conversion factor. Except for some starbursting systems (Mrk33, Tolo89, NGC3049), dust in the diffuse ISM dominates the IR power.

  10. Constraining Primordial Non-Gaussianity With the Abundance of High Redshift Clusters

    E-Print Network [OSTI]

    James Robinson; Eric Gawiser; Joseph Silk

    2000-05-25T23:59:59.000Z

    We show how observations of the evolution of the galaxy cluster number abundance can be used to constrain primordial non-Gaussianity in the universe. We carry out a maximum likelihood analysis incorporating a number of current datasets and accounting for a wide range of sources of systematic error. Under the assumption of Gaussianity, the current data prefer a universe with matter density $\\Omega_m\\simeq 0.3$ and are inconsistent with $\\Omega_m=1$ at the $2\\sigma$ level. If we assume $\\Omega_m=1$, the predicted degree of cluster evolution is consistent with the data for non-Gaussian models where the primordial fluctuations have at least two times as many peaks of height $3\\sigma$ or more as a Gaussian distribution does. These results are robust to almost all sources of systematic error considered: in particular, the $\\Omega_m=1$ Gaussian case can only be reconciled with the data if a number of systematic effects conspire to modify the analysis in the right direction. Given an independent measurement of $\\Omega_m$, the techniques described here represent a powerful tool with which to constrain non-Gaussianity in the primordial universe, independent of specific details of the non-Gaussian physics. We discuss the prospects and strategies for improving the constraints with future observations.

  11. A very reduced upper limit on the interstellar abundance of beryllium

    E-Print Network [OSTI]

    Guillaume Hébrard; Martin Lemoine; Roger Ferlet; Alfred Vidal-Madjar

    1997-02-26T23:59:59.000Z

    We present the results of observations of the $\\lambda 3130.4$ \\AA interstellar absorption line of Be II in the direction of zeta Per. The data were obtained at the Canada-France-Hawaii 3.6m Telescope using the Coud\\'e f/4 Gecko spectrograph at a resolving power $\\simeq 1.1 \\times 10^5$, and a signal-to-noise ratio S/N $\\simeq$ 2000. The Be II line is not detected, and we obtain an upper limit on the equivalent width $W_{3130.4}\\leq30$ $\\mu$\\AA. This upper limit is 7 times below the lowest upper limit ever reported hitherto. The derived interstellar abundance is ($^9$Be/H) $\\leq 7 \\times 10^{-13}$, not corrected for the depletion of Be onto interstellar grains; it corresponds to an upper limit $\\delta_{Be} \\leq -1.5$ dex on the depletion factor of Be. As such, it argues in favour of models of formation of dust grains in stellar atmospheres.

  12. Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample

    E-Print Network [OSTI]

    Draine, B T; Bendo, G; Gordon, K D; Smith, J D T; Armus, L; Engelbracht, C W; Helou, G; Kennicutt, R C; Li, A; Roussel, H; Walter, F; Calzetti, D; Moustakas, J; Murphy, E J; Rieke, G H; Bot, C; Hollenbach, D J; Sheth, K; Teplitz, H I

    2007-01-01T23:59:59.000Z

    Physical dust models are presented for 65 galaxies in the SINGS survey that are strongly detected in the four IRAC bands and three MIPS bands. For each galaxy we estimate (1) the total dust mass, (2) the fraction of the dust mass contributed by PAHs, and (3) the intensity of the starlight heating the dust grains. We find that spiral galaxies have dust properties resembling the dust in the local region of the Milky Way, with similar dust-to-gas ratio, and similar PAH abundance. The observed SEDs, including galaxies with SCUBA photometry, can be reproduced by dust models that do not require "cold" (T8.1, grains contain a substantial fraction of interstellar Mg, Si and Fe. Galaxies with A_O8.1 have a median q_PAH=3.55%. The derived dust masses favor a value X_CO approx 4e20 cm^{-2}(K kms)^{-1} for the CO to H_2 conversion factor. Except for some starbursting systems (Mrk33, Tolo89, NGC3049), dust in the diffuse ISM dominates the IR power.

  13. An empirical calibration of nebular abundances based on the sulphur emission lines

    E-Print Network [OSTI]

    A. I. Diaz; E. Perez-Montero

    1999-09-29T23:59:59.000Z

    We present an empirical calibration of nebular abundances based on the strong emission lines of [SII] and [SIII] in the red part of the spectrum through the definition of a sulphur abundance parameter S23. This calibration presents two important advantages against the commonly used one based on the optical oxygen lines: it remains single-valued up to abundances close to solar and is rather independent of the degree of ionization of the nebula.

  14. Is Nuclear Energy the Solution?

    E-Print Network [OSTI]

    Saier, Milton H.; Trevors, Jack T.

    2010-01-01T23:59:59.000Z

    the potential of nuclear power to combat global warming havecompetitive today, and for nuclear power to succeed, it must

  15. JB RISOE 20-05-2003 Advanced 700C PF Power Plant

    E-Print Network [OSTI]

    prices of imported coal · Security of supply is threatened without coal · Clean Coal Technology in efficiency of Elsam's coal-fired power plants 1950 19701960 19901980 20202000 2010 30 32 34 36 38 40 42 44 46 of Coal Based Power Generation · Abundant reserves · Many independent producers of coal · Low and stable

  16. Combined Heat & Power (CHP) -A Clean Energy Solution for Industry

    E-Print Network [OSTI]

    Parks, H.; Hoffman, P.; Kurtovich, M.

    From the late 1970's to the early 1990's cogeneration or CHP saw enormous growth, especially in the process industries. By 1994, CHP provided 42 GW of electricity generation capacity -about 6 percent of the U.S. total. Three manufacturing industries...

  17. Optimized Jacobian Matrix Solution of a generalized electric power network

    E-Print Network [OSTI]

    Moore, Jimmie Archer

    1970-01-01T23:59:59.000Z

    the logic described in Appendix 2. The remain~. ng logic formulation has been discussed in Chapter II. CHAPTER IV CONCEVSIONS T\\1e technique presented in this paper will solve any electrica' system rot containing voltage regulated bus es in about four..., until a technique of maintaining the renumbered system instead of the originally numbered system can be developeo. , the Gauss- Seidel technique remains clearly superior for the average electrica network requiring pcwer flow analysis. However...

  18. Case Study - Florida Power & Light - Smart Grid Solutions Strengthen...

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

    providing customers with information and data displays so they can better control their electricity consumption and costs. Each customer with an activated smart meter can view...

  19. Developing a power supply solution for a mobile robot

    E-Print Network [OSTI]

    Zachmann, Gabriel

    (Technical Informatics and Computer Systems) Prof. Dr. Gabriel Zachmann (Computer Graphics) Prof. Dr

  20. Glendale Water and Power - Solar Solutions Program | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy ChinaofSchaefer To: CongestionDevelopment of a downhole wirelineCompaniesGilbertNonprofit

  1. Mid America Advanced Power Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal Pwer Plant JumpMarysville, Ohio:Menomonee| OpenMickey HotVII, Cologne,Caldera, New Mexico |Mid

  2. Johnson Controls Saft Advanced Power Solutions | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluatingGroup |Jilin Zhongdiantou New Energy Co LtdJinzhouJoe Wheeler Elec

  3. Parent Stars of Extrasolar Planets. VIII. Chemical Abundances for 18 Elements in 31 Stars

    E-Print Network [OSTI]

    Guillermo Gonzalez; Chris Laws

    2007-04-17T23:59:59.000Z

    We present the results of detailed spectroscopic abundance analyses for 18 elements in 31 nearby stars with planets. The resulting abundances are combined with other similar studies of nearby stars with planets and compared to a sample of nearby stars without detected planets. We find some evidence for abundance differences between these two samples for Al, Si and Ti. Some of our results are in conflict with a recent study of stars with planets in the SPOCS database. We encourage continued study of the abundance patterns of stars with planets to resolve these discrepancies.

  4. Remarkable Amphibian Biomass and Abundance in an Isolated Wetland: Implications for Wetland

    E-Print Network [OSTI]

    Todd, Brian

    DOI: 10.1111/j.1523-1739.2006.00443.x #12;2 Amphibian Biomass and Abundance Gibbons et al. Biomasa y

  5. Life History, Abundance, and Distribution of the Spotted Ratfish, Hydrolagus colliei

    E-Print Network [OSTI]

    Barnett, Lewis A.K.

    2008-01-01T23:59:59.000Z

    captive H. colliei, taken from Puget Sound, WA, deposited 18most abundant groundfish in Puget Sound, Washington (Palssonand diel migrations in Puget Sound. If these behaviors are

  6. The Relative Abundance of Desert Tortoises on the Nevada Test Site within Ecological Landform Units

    SciTech Connect (OSTI)

    Roy Woodward, Kurt R. Rautenstrauch, Derek B. Hall, and W. Kent Ostler

    1998-09-01T23:59:59.000Z

    Sign-survey transects were sampled in 1996 to better determine the relative abundance of desert tortoises on the Nevada Test Site (NTS). These transects were sampled within ecological land-form units (ELUs), which are small, ecologically homogeneous units of land. Two-hundred and six ELUs were sampled by walking 332 transects totaling 889 kilometers (km) (552 miles [mi]). These ELUs covered 528 km{sup 2} (204 mi{sup 2}). Two-hundred and eighty-one sign were counted. An average of 0.32 sign was found per km walked. Seventy percent of the area sampled had a very low abundance of tortoises, 29 percent had a low abundance, and 1 percent had a moderate abundance. A revised map of the relative abundance of desert tortoise on the NTS is presented. Within the 1,330 km{sup 2} (514 mi{sup 2}) of desert tortoise habitat on the NTS, 49 percent is classified as having no tortoises or a very low abundance, 18 percent has a low or moderate abundance, 12 percent is unclassified land being used by the Yucca Mountain Site Characterization Project, and the remaining 21 percent still has an unknown abundance of desert tortoises. Based on the results of this work, the amount of tortoise habitat previously classified as having an unknown or low-moderate abundance, and on which clearance surveys and on-site monitoring was required, has been reduced by 20 percent.

  7. The relative abundance of desert tortoises on the Nevada Test Site within ecological landform units

    SciTech Connect (OSTI)

    Woodward, R. [Bechtel National (United States); Rautenstrauch, K.R. [Science Applications International Corp. (United States); Hall, D.B.; Ostler, W.K. [Bechtel Nevada (United States)

    1998-09-01T23:59:59.000Z

    Sign-survey transects were sampled in 1996 to better determine the relative abundance of desert tortoises on the Nevada Test Site (NTS). These transects were sampled within ecological land-form units (ELUs), which are small, ecologically homogeneous units of land. Two-hundred and six ELUs were sampled by walking 332 transects totaling 889 kilometers (km). These ELUs covered 528 km{sup 2}. Two-hundred and eight-one sign were counted. An average of 0.32 sign was found per km walked. Seventy percent of the area sampled had a very low abundance of tortoises, 29% had a low abundance, and 1% had a moderate abundance. A revised map of the relative abundance of desert tortoise on the NTS is presented. Within the 1,330 km{sup 2} of desert tortoise habitat on the NTS, 49% is classified as having no tortoises or a very low abundance, 18% has a low or moderate abundance, 12% is unclassified land being used by the Yucca Mountain Site Characterization Project, and the remaining 21% still has an unknown abundance of desert tortoises. Based on the results of this work, the amount of tortoise habitat previously classified as having an unknown or low-moderate abundance, and on which clearance surveys and on-site monitoring was required, has been reduced by 20%.

  8. Powers of Ten Thousand: Navigating in Large Information Spaces

    E-Print Network [OSTI]

    Powers of Ten Thousand: Navigating in Large Information Spaces Henry Lieberman Media Laboratory large display space, for example, a street map of the entire United States? The traditional solution, on a scale of at least 1 to 10,000. Powers of ten thousand The book and film Powers of Ten [Morrison

  9. Survey and Analysis of Power Control for Collaborative Networks

    E-Print Network [OSTI]

    Cambridge, University of

    Survey and Analysis of Power Control for Collaborative Networks Weisi Guo1, Ioannis Chatzigeorgiou1. In Section III, we review existing power control solutions for relay and cooperative systems and see how they behave with different parameters. We will then introduce our own work on cooperative power control

  10. Power Transmission Network Design by Greedy Randomized Adaptive Path Relinking

    E-Print Network [OSTI]

    Fisher, Kathleen

    different solutions could be reached exploring these different trajectories. The electric power system1 Power Transmission Network Design by Greedy Randomized Adaptive Path Relinking Haroldo Faria Jr Adaptive Path Relinking, applied to solve static power transmission network design problems. This new

  11. Power Save Adaptation Algorithm for Multimedia Streaming to Mobile Devices

    E-Print Network [OSTI]

    Power Save Adaptation Algorithm for Multimedia Streaming to Mobile Devices Janet Adams Performance. This paper proposes a power save adaptation algorithm for mobile multimedia streaming that aims to increase stages: data reception, decoding and playing and power saving solutions for each of these stages

  12. USING ACTIVE POWER FILTERS TO IMPROVE POWER Luis A. Morn(1)

    E-Print Network [OSTI]

    Catholic University of Chile (Universidad Católica de Chile)

    quality and supply reliability. Voltage quality problems relates to any failure of equipment due and their solutions with power electronics based equipment. Shunt, hybrid and series active power filters. - INTRODUCTION The proliferation of microelectronics processors in a wide range of equipments, from home VCRs

  13. Solution High-Energy Burst Assembly (SHEBA) results from subprompt critical experiments with uranyl fluoride fuel

    SciTech Connect (OSTI)

    Cappiello, C.C.; Butterfield, K.B.; Sanchez, R.G.; Bounds, J.A.; Kimpland, R.H.; Damjanovich, R.P.; Jaegers, P.J.

    1997-08-01T23:59:59.000Z

    Experiments were performed to measure a variety of parameters for SHEBA: behavior of the facility during transient and steady-state operation; characteristics of the SHEBA fuel; delayed-critical solution height vs solution temperature; initial reactor period and reactivity vs solution height; calibration of power level vs reactor power instrumentation readings; flux profile in SHEBA; radiation levels and neutron spectra outside the assembly for code verification and criticality alarm and dosimetry purposes; and effect on reactivity of voids in the fuel.

  14. Low 60Fe abundance in Semarkona and Sahara 99555

    E-Print Network [OSTI]

    Tang, Haolan

    2015-01-01T23:59:59.000Z

    Iron-60 (t1/2=2.62 Myr) is a short-lived nuclide that can help constrain the astrophysical context of solar system formation and date early solar system events. A high abundance of 60Fe (60Fe/56Fe= 4x10-7) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. However, our previous MC-ICPMS measurements of a wide range of meteoritic materials, including chondrules, showed that 60Fe was present in the early solar system at a much lower level (60Fe/56Fe=10-8). The reason for the discrepancy is unknown but only two Semarkona chondrules were measured by MC-ICPMS and these had Fe/Ni ratios below ~2x chondritic. Here, we show that the initial 60Fe/56Fe ratio in Semarkona chondrules with Fe/Ni ratios up to ~24x chondritic is 5.4x10-9. We also establish the initial 60Fe/56Fe ratio at the time of crystallization of the Sahara 99555 angrite, a chronological anchor, to be 1.97x10-9. The...

  15. Molecular hydrogen abundances of galaxies in the EAGLE simulations

    E-Print Network [OSTI]

    Lagos, Claudia del P; Schaye, Joop; Furlong, Michelle; Frenk, Carlos S; Bower, Richard G; Schaller, Matthieu; Theuns, Tom; Trayford, James W; Bahe, Yannick M; Vecchia, Claudio Dalla

    2015-01-01T23:59:59.000Z

    We investigate the abundance of galactic molecular hydrogen (H$_2$) in the "Evolution and Assembly of GaLaxies and their Environments" (EAGLE) cosmological hydrodynamic simulations. We assign H$_2$ masses to gas particles in the simulations in post-processing using two different prescriptions that depend on the local dust-to-gas ratio and the interstellar radiation field. Both result in H$_2$ galaxy mass functions that agree well with observations in the local and high-redshift Universe. The simulations reproduce the observed scaling relations between the mass of H$_2$ and the stellar mass, star formation rate and stellar surface density. Towards high edshifts, galaxies in the simulations display larger H$_2$ mass fractions, and correspondingly lower H$_2$ depletion timescales, also in good agreement with observations. The comoving mass density of H$_2$ in units of the critical density, $\\Omega_{\\rm H_2}$, peaks at $z\\approx 1.2-1.5$, later than the predicted peak of the cosmic star formation rate activity, a...

  16. LARGE ABUNDANCES OF POLYCYCLIC AROMATIC HYDROCARBONS IN TITAN'S UPPER ATMOSPHERE

    SciTech Connect (OSTI)

    Lopez-Puertas, M.; Funke, B.; Garcia-Comas, M. [Instituto de Astrofisica de Andalucia (CSIC), E-18080 Granada (Spain); Dinelli, B. M. [ISAC-CNR, I-40129 Bologna (Italy); Adriani, A.; D'Aversa, E. [IAPS-INAF, I-00133 Rome (Italy); Moriconi, M. L. [ISAC-CNR, I-00133 Rome (Italy); Boersma, C.; Allamandola, L. J., E-mail: puertas@iaa.es [NASA Ames Research Center, Moffett Field, CA 94035-1000 (United States)

    2013-06-20T23:59:59.000Z

    In this paper, we analyze the strong unidentified emission near 3.28 {mu}m in Titan's upper daytime atmosphere recently discovered by Dinelli et al. We have studied it by using the NASA Ames PAH IR Spectroscopic Database. The polycyclic aromatic hydrocarbons (PAHs), after absorbing UV solar radiation, are able to emit strongly near 3.3 {mu}m. By using current models for the redistribution of the absorbed UV energy, we have explained the observed spectral feature and have derived the vertical distribution of PAH abundances in Titan's upper atmosphere. PAHs have been found to be present in large concentrations, about (2-3) Multiplication-Sign 10{sup 4} particles cm{sup -3}. The identified PAHs have 9-96 carbons, with a concentration-weighted average of 34 carbons. The mean mass is {approx}430 u; the mean area is about 0.53 nm{sup 2}; they are formed by 10-11 rings on average, and about one-third of them contain nitrogen atoms. Recently, benzene together with light aromatic species as well as small concentrations of heavy positive and negative ions have been detected in Titan's upper atmosphere. We suggest that the large concentrations of PAHs found here are the neutral counterpart of those positive and negative ions, which hence supports the theory that the origin of Titan main haze layer is located in the upper atmosphere.

  17. The Water Vapor Abundance in Orion KL Outflows

    E-Print Network [OSTI]

    J. Cernicharo; J. R. Goicoechea; F. Daniel; M. R. Lerate; M. J. Barlow; B. M. Swinyard; E. van Dishoeck; T. L. Lim; S. Viti; J. Yates

    2006-08-16T23:59:59.000Z

    We present the detection and modeling of more than 70 far-IR pure rotational lines of water vapor, including the 18O and 17O isotopologues, towards Orion KL. Observations were performed with the Long Wavelength Spectrometer Fabry-Perot (LWS/FP; R~6800-9700) on board the Infrared Space Observatory (ISO) between ~43 and ~197 um. The water line profiles evolve from P-Cygni type profiles (even for the H2O18 lines) to pure emission at wavelengths above ~100 um. We find that most of the water emission/absorption arises from an extended flow of gas expanding at 25+-5 kms^-1. Non-local radiative transfer models show that much of the water excitation and line profile formation is driven by the dust continuum emission. The derived beam averaged water abundance is 2-3x10^-5. The inferred gas temperature Tk=80-100 K suggests that: (i) water could have been formed in the "plateau" by gas phase neutral-neutral reactions with activation barriers if the gas was previously heated (e.g. by shocks) to >500 K and/or (ii) H2O formation in the outflow is dominated by in-situ evaporation of grain water-ice mantles and/or (iii) H2O was formed in the innermost and warmer regions (e.g. the hot core) and was swept up in ~1000 yr, the dynamical timescale of the outflow.

  18. Germanium abundances in lunar basalts: Evidence of mantle metasomatism

    SciTech Connect (OSTI)

    Dickinson, T.; Taylor, G.J.; Keil, T.K.; Bild, R.W.

    1988-01-01T23:59:59.000Z

    To fill in gaps in the present Ge data base, mare basalts were analyzed for Ge and other elements by RNAA and INAA. Mare basalts from Apollo 11, 12, 15, 17 landing sites are rather uniform in Ge abundance, but Apollo 14 aluminous mare basalts and KREEP are enriched in Ge by factors of up to 300 compared to typical mare basalts. These Ge enrichments are not associated with other siderophile element enrichments and, thus, are not due to differences in the amount of metal segregated during core formation. Based on crystal-chemical and inter-element variations, it does not appear that the observed Ge enrichments are due to silicate liquid immiscibility. Elemental ratios in Apollo 14 aluminous mare basalts, green and orange glass, average basalts and KREEP suggest that incorporation of late accreting material into the source regions or interaction of the magmas with primitive undifferentiated material is not a likely cause for the observed Ge enrichments. We speculate that the most plausible explanation for these Ge enrichments is complexing and concentration of Ge by F, Cl or S in volatile phases. In this manner, the KREEP basalt source regions may have been metasomatized and Apollo 14 aluminous mare basalt magmas may have become enriched in Ge by interacting with these metasomatized areas. The presence of volatile- and Ge-rich regions in the Moon suggests that the Moon was never totally molten. 71 refs., 1 fig., 6 tabs.

  19. Power superconducting power transmission cable

    DOE Patents [OSTI]

    Ashworth, Stephen P. (Cambridge, GB)

    2003-01-01T23:59:59.000Z

    The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

  20. Power Right. Power Smart. Efficient Computer Power Supplies and...

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

    AC power that you get from your electric company into the DC power consumed by most electronics, including your computer. We expect our power supplies to be safe, reliable, and...

  1. Silicon Valley Power and Oklahoma Municipal Power Authority Win...

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

    Silicon Valley Power and Oklahoma Municipal Power Authority Win 2014 Public Power Wind Awards Silicon Valley Power and Oklahoma Municipal Power Authority Win 2014 Public Power Wind...

  2. Plasma instrumentation for fusion power reactor control

    SciTech Connect (OSTI)

    Sager, G.T.; Bauer, J.F.; Maya, I.; Miley, G.H.

    1985-07-01T23:59:59.000Z

    Feedback control will be implemented in fusion power reactors to guard against unpredicted behavior of the plant and to assure desirable operation. In this study, plasma state feedback requirements for plasma control by systems strongly coupled to the plasma (magnet sets, RF, and neutral beam heating systems, and refueling systems) are estimated. Generic considerations regarding the impact of the power reactor environment on plasma instrumentation are outlined. Solutions are proposed to minimize the impact of the power reactor environment on plasma instrumentation. Key plasma diagnostics are evaluated with respect to their potential for upgrade and implementation as power reactor instruments.

  3. Tidal power

    SciTech Connect (OSTI)

    Hammons, T.J. (Glasgow Univ., Scotland (United Kingdom))

    1993-03-01T23:59:59.000Z

    The paper reviews the physics of tidal power considering gravitational effects of moon and sun; semidiurnal, diurnal, and mixed tides; and major periodic components that affect the tidal range. Shelving, funneling, reflection, and resonance phenomena that have a significant effect on tidal range are also discussed. The paper then examines tidal energy resource for principal developments estimated from parametric modeling in Europe and worldwide. Basic parameters that govern the design of tidal power schemes in terms of mean tidal range and surface area of the enclosed basin are identified. While energy extracted is proportional to the tidal amplitude squared, requisite sluicing are is proportional to the square root of the tidal amplitude. Sites with large tidal amplitudes are therefore best suited for tidal power developments, whereas sites with low tidal amplitudes have sluicing that may be prohibitive. It is shown that 48% of the European tidal resource is in the United Kingdom, 42% in France and 8% in Ireland, other countries having negligible potential. Worldwide tidal resource is identified. Tidal barrage design and construction using caissons is examined, as are alternative operating modes (single-action generation, outflow generation, flood generation, two-way generation, twin basin generation, pumping, etc), development trends and possibilities, generation cost at the barrage boundary, sensitivity to discount rates, general economics, and markets. Environmental effects, and institutional constraints to the development of tidal barrage schemes are also discussed.

  4. Nonlinear modal interaction in HVDC/AC power systems with dc power modulation

    SciTech Connect (OSTI)

    Ni, Y.X. [Tsinghua Univ., Beijing (China)] [Tsinghua Univ., Beijing (China); Vittal, V.; Kliemann, W.; Fouad, A.A. [Iowa State Univ., Ames, IA (United States)] [Iowa State Univ., Ames, IA (United States)

    1996-11-01T23:59:59.000Z

    In this paper investigation of nonlinear modal interaction using the normal form of vector fields technique is extended to HVDC/AC power systems with dc power modulation. The ac-dc interface equations are solved to form a state space model with second order approximation. Using the normal form technique, the system`s nonlinear dynamic characteristics are obtained. The proposed approach is applied to a 4-generator HVDC/AC test power system, and compare with the time domain solution.

  5. Fissile solution measurement apparatus

    DOE Patents [OSTI]

    Crane, T.W.; Collinsworth, P.R.

    1984-06-11T23:59:59.000Z

    An apparatus for determining the content of a fissile material within a solution by detecting delayed fission neutrons emitted by the fissile material after it is temporarily irradiated by a neutron source. The apparatus comprises a container holding the solution and having a portion defining a neutron source cavity centrally disposed within the container. The neutron source cavity temporarily receives the neutron source. The container has portions defining a plurality of neutron detector ports that form an annular pattern and surround the neutron source cavity. A plurality of neutron detectors count delayed fission neutrons emitted by the fissile material. Each neutron detector is located in a separate one of the neutron detector ports.

  6. Village Power `97. Proceedings

    SciTech Connect (OSTI)

    Cardinal, J.; Flowers, L.; Taylor, R.; Weingart, J. [eds.

    1997-09-01T23:59:59.000Z

    It is estimated that two billion people live without electricity and its services. In addition, there is a sizable number of rural villages that have limited electrical service, with either part-day operation by diesel gen-sets or partial electrification (local school or community center and several nearby houses). For many villages connected to the grid, power is often sporadically available and of poor quality. The U.S. National Renewable Energy Laboratory (NREL) in Golden, Colorado, has initiated a program to address these potential electricity opportunities in rural villages through the application of renewable energy (RE) technologies. The objective of this program is to develop and implement applications that demonstrate the technical performance, economic competitiveness, operational viability, and environmental benefits of renewable rural electric solutions, compared to the conventional options of line extension and isolated diesel mini-grids. These four attributes foster sustainability; therefore, the program is entitled Renewables for Sustainable Village Power (RSVP). The RSVP program is a multi-disciplinary, multi-technology, multi-application program composed of six key activities, including village application development, computer model development, systems analysis, pilot project development, technical assistance, and an Internet-based village power project database. The current program emphasizes wind, photovoltaics (PV), and their hybrids with diesel gen-sets. NREL`s RSVP team is currently involved in rural electricity projects in thirteen countries, with U.S., foreign, and internationally based agencies and institutions. This document contains reports presented at the Proceedings of Village Power, 1997. Individual projects have been processed separately for the United States Department of Energy databases.

  7. THE CORONAL ABUNDANCES OF MID-F DWARFS

    SciTech Connect (OSTI)

    Wood, Brian E.; Laming, J. Martin [Naval Research Laboratory, Space Science Division, Washington, DC 20375 (United States)

    2013-05-10T23:59:59.000Z

    A Chandra spectrum of the moderately active nearby F6 V star {pi}{sup 3} Ori is used to study the coronal properties of mid-F dwarfs. We find that {pi}{sup 3} Ori's coronal emission measure distribution is very similar to those of moderately active G and K dwarfs, with an emission measure peak near log T = 6.6 seeming to be ubiquitous for such stars. In contrast to coronal temperature, coronal abundances are known to depend on spectral type for main sequence stars. Based on this previously known relation, we expected {pi}{sup 3} Ori's corona to exhibit an extremely strong ''first ionization potential (FIP) effect'', a phenomenon first identified on the Sun where elements with low FIP are enhanced in the corona. We instead find that {pi}{sup 3} Ori's corona exhibits a FIP effect essentially identical to that of the Sun and other early G dwarfs, perhaps indicating that the increase in FIP bias toward earlier spectral types stops or at least slows for F stars. We find that {pi}{sup 3} Ori's coronal characteristics are significantly different from two previously studied mid-F stars, Procyon (F5 IV-V) and {tau} Boo (F7 V). We believe {pi}{sup 3} Ori is more representative of the coronal characteristics of mid-F dwarfs, with Procyon being different because of luminosity class, and {tau} Boo being different because of the effects of one of two close companions, one stellar ({tau} Boo B: M2 V) and one planetary.

  8. Wind power and Wind power and

    E-Print Network [OSTI]

    Wind power and the CDM #12; Wind power and the CDM Emerging practices in developing wind power 2005 Jyoti P. Painuly, Niels-Erik Clausen, Jørgen Fenhann, Sami Kamel and Romeo Pacudan #12; WIND POWER AND THE CDM Emerging practices in developing wind power projects for the Clean Development Mechanism Energy

  9. Techniques and Technology Article Aerial Surveys for Estimating Wild Turkey Abundance in

    E-Print Network [OSTI]

    Butler, Matthew J.

    Techniques and Technology Article Aerial Surveys for Estimating Wild Turkey Abundance in the Texas Aerial surveys have been used to estimate abundance of several wild bird species including wild turkeys (Meleagris gallopavo). We used inflatable turkey decoys at 3 study sites in the Texas Rolling Plains

  10. OCCUPANCY DISTRIBUTIONS ARISING IN SAMPLING FROM GIBBS-POISSON ABUNDANCE MODELS

    E-Print Network [OSTI]

    together with a sampling model. We start with a discrete model of iid stochastic species abundances, each, which is a measure of richness or diversity of species. We rederive the sam- pling formulae1 , SERVET MART´INEZ2 (iid) stochastic species abundances d = 1, ..., n , based on Gibbs

  11. X-shooter Science Verification Proposal Title: Precise abundance determination of extremely metal poor HII galaxies

    E-Print Network [OSTI]

    Liske, Jochen

    the task of obtaining a data base of HII galaxies with accurately derived abundances and a realistic poor HII galaxies Investigators Institute EMAIL ´Angeles I. D´iaz UAM angeles.diaz@uam.es Roberto and abundances derived from SDSS data can only #12;be taken as broad estimates and challenges the methodology

  12. A unified model of species immigration, extinction and abundance on islands

    E-Print Network [OSTI]

    Harmon, Luke

    ORIGINAL ARTICLE A unified model of species immigration, extinction and abundance on islands James and extinction rates as functions of species richness at dynamic equilibrium. In contrast, the approach results highlight the importance of species abundances as indi- cators of immigration and extinction rates

  13. The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle

    E-Print Network [OSTI]

    Richardson, John

    The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle Matthias R. Aellig Alamos National Lab., Los Alamos, NM 87545 Abstract We investigate the helium abundance in the solar wind of 1994 and early 2000 are analyzed. In agreement with similar work for previous solar cycles, we find

  14. The Texas Quail Index: Evaluating Predictors of Quail Abundance Using Citizen Science

    E-Print Network [OSTI]

    Reyna, Kelly Shane

    2009-05-15T23:59:59.000Z

    Quail Index (TQI) was a 5-year citizen-science project that evaluated several indices of quail abundance and habitat parameters as predictors of quail abundance during the ensuing fall. I found that spring cock-call counts explained 41% of the variation...

  15. Fully corrected estimates of common minke whale abundance in West Greenland in 2007

    E-Print Network [OSTI]

    Laidre, Kristin L.

    Fully corrected estimates of common minke whale abundance in West Greenland in 2007 M.P. HEIDE West Greenland in August and September 2007. A total of 8,670km of survey effort covered 11 strata SURVEY; SATELLITE TAGGING; WEST GREENLAND minke whales to fully corrected total estimates of abundance

  16. MODELING PHYTOPLANKTON ABUNDANCE IN SAGINAW BAY, LAKE HURON: USING ARTIFICIAL NEURAL NETWORKS TO DISCERN FUNCTIONAL INFLUENCE

    E-Print Network [OSTI]

    MODELING PHYTOPLANKTON ABUNDANCE IN SAGINAW BAY, LAKE HURON: USING ARTIFICIAL NEURAL NETWORKS; phytoplankton Abbreviations: ANN, artificial neural network; ClÀ , chloride; DOC, dissolved organic carbon; Kd Phytoplankton abundance, as chl a, in Saginaw Bay, Lake Huron was modeled using arti- ficial neural networks

  17. Identification in Pea Seed Mitochondria of a Late-Embryogenesis Abundant Protein Able to

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    lack of well-ordered tertiary structure of LEA proteins preventing their use as catalysts, severalIdentification in Pea Seed Mitochondria of a Late-Embryogenesis Abundant Protein Able to Protect, 38054 Grenoble cedex 9, France (D.G.) Late-embryogenesis abundant (LEA) proteins are hydrophilic

  18. The Oxygen Abundance of Nearby Galaxies from Sloan Digital Sky Survey Spectra

    E-Print Network [OSTI]

    L. S. Pilyugin; T. X. Thuan

    2007-07-19T23:59:59.000Z

    We have derived the oxygen abundance for a sample of nearby galaxies in the Data Release 5 of the Sloan Digital Sky Survey (SDSS) which possess at least two independent spectra of one or several HII regions with a detected [OIII]4363 auroral line. Since, for nearby galaxies, the [OII]3727 nebular line is out of the observed wavelength range, we propose a method to derive (O/H)_ff abundances using the classic Te method coupled with the ff relation. (O/H)_7325 abundances have also been determined, based on the [OII]7320,7330 line intensities, and using a small modification of the standard Te method. The (O/H)_ff and (O/H)_7325 abundances have been derived with both the one- and two-dimensional t_2 - t_3 relations. It was found that the (O/H)_ff abundances derived with the parametric two-dimensional t_2 - t_3 relation are most reliable. Oxygen abundances have been determined in 29 nearby galaxies, based on 84 individual abundance determinations in HII regions. Because of our selection methods, the metallicity of our galaxies lies in the narrow range 8.2 oxygen abundances in the disk of the spiral galaxy NGC 4490 is determined for the first time.

  19. Instructions for use Petrology, trace element abundances and oxygen isotopic1

    E-Print Network [OSTI]

    Tsunogai, Urumu

    Instructions for use #12;1 Petrology, trace element abundances and oxygen isotopic1 compositions@jamstec.go.jp15 16 17 #12;2 ABSTRACT1 We report the petrology, trace element abundances and oxygen isotopic and isotopic compositions as well as in their petrology.1 CAIs are composed of refractory minerals

  20. Nontoxic and Abundant Copper Zinc Tin Sulfide Nanocrystals for Potential High-Temperature Thermoelectric Energy Harvesting

    E-Print Network [OSTI]

    Chen, Yong P.

    and abundant copper zinc tin sulfide (CZTS) nanocrystals for potential thermoelectric applications. The CZTS sulfide (CZTS) as a nontoxic and abundant thermoelectric material and characterized its thermoelectric materials, the elements in the composition of CZTS are in extremely high abundancethe natural reserves

  1. 1.2 Solutions

    E-Print Network [OSTI]

    In other words, the graph of the ... coef?cient p0 — (k/r) of the exponential term in Eq. (19). 1f p0 > Mr ..... be other solutions, then perhaps we should continue to search for them. .... Then the tensile force in the rod does not enter the equation.

  2. The Abundance of Fluorine in Normal G and K Stars of the Galactic Thin Disk

    E-Print Network [OSTI]

    Pilachowski, Catherine A

    2015-01-01T23:59:59.000Z

    The abundance of fluorine is determined from the (2-0) R9 2.3358 micron feature of the molecule HF for several dozen normal G and K stars in the Galactic thin disk from spectra obtained with the Phoenix IR spectrometer on the 2.1-m telescope at Kitt Peak. The abundances are analyzed in the context of Galactic chemical evolution to explore the contributions of supernovae and asymptotic giant branch (AGB) stars to the abundance of fluorine in the thin disk. The average abundance of fluorine in the thin disk is found to be [F/Fe] = +0.23 +/- 0.03, and the [F/Fe] ratio is flat or declines slowly with metallicity in the range from -0.6 supernovae contributes significantly to the Galactic fluorine abundance, although contributions from AGB stars may also be important.

  3. Power Recovery

    E-Print Network [OSTI]

    Murray, F.

    , will be the use of the ASTM Theoretical Steam Rate Tables. In addition, the author's experience regarding the minimum size for power recovery units that are economic in a Culf Coast plant will be presented. INTROD\\Jr.'rION When surveying an operation... will be discussed in detail. Each term in the equation will be considered in English units. Secondly, the use of Mollier diagrams to estimate the enthalphy change between the initial and final conditions will be considered. The last method, specific to steam...

  4. Yakama Power

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsingWhatY-12 recognized for ...BER/NERSCYakama Power May

  5. Fusion Power

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.Newof EnergyFunding Opportunity fromFusion Links Fusion

  6. Better Buildings Residential Program Solution Center Demonstration...

    Energy Savers [EERE]

    Better Buildings Residential Program Solution Center Demonstration Better Buildings Residential Program Solution Center Demonstration Better Buildings Residential Program Solution...

  7. Earth-abundant semiconductors for photovoltaic applications | The Ames

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign:INEA :Work4/11Computational Earth Science SHARE

  8. Harvesting Energy from Abundant, Low Quality Sources of Heat - Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanford LEED&soil HanfordHappyHarold PaulHarry

  9. Power management system

    DOE Patents [OSTI]

    Algrain, Marcelo C. (Peoria, IL); Johnson, Kris W. (Washington, IL); Akasam, Sivaprasad (Peoria, IL); Hoff, Brian D. (East Peoria, IL)

    2007-10-02T23:59:59.000Z

    A method of managing power resources for an electrical system of a vehicle may include identifying enabled power sources from among a plurality of power sources in electrical communication with the electrical system and calculating a threshold power value for the enabled power sources. A total power load placed on the electrical system by one or more power consumers may be measured. If the total power load exceeds the threshold power value, then a determination may be made as to whether one or more additional power sources is available from among the plurality of power sources. At least one of the one or more additional power sources may be enabled, if available.

  10. Solar powered desalination system

    E-Print Network [OSTI]

    Mateo, Tiffany Alisa

    2011-01-01T23:59:59.000Z

    2008, uses concentrated solar power to split water. Figurethe main reason the potential for solar power is boundless.a clean energy source, solar power is inexhaustible, fairly

  11. ELECTROCHEMICAL POWER FOR TRANSPORTATION

    E-Print Network [OSTI]

    Cairns, Elton J.

    2012-01-01T23:59:59.000Z

    electric power generating plant, and the distributionrequired on the power-generating plant and not on the vehi-in either power-generating plants or combustion engines,

  12. Southwestern Power Administration

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

    Courses Instructors NERC Continuing Education Power Operations Training Center You'll find the "Power" of learning at Southwestern's Power Operations Training Center (POTC). POTC's...

  13. POWER PURCHASE AGREEMENT DELMARVA POWER & LIGHT COMPANY

    E-Print Network [OSTI]

    Firestone, Jeremy

    POWER PURCHASE AGREEMENT between DELMARVA POWER & LIGHT COMPANY ("Buyer") and BLUEWATER WIND 3.5 Energy Forecasts, Scheduling and Balancing.......................................... 39 3

  14. Power oscillator

    DOE Patents [OSTI]

    Gitsevich, Aleksandr (Montgomery Village, MD)

    2001-01-01T23:59:59.000Z

    An oscillator includes an amplifier having an input and an output, and an impedance transformation network connected between the input of the amplifier and the output of the amplifier, wherein the impedance transformation network is configured to provide suitable positive feedback from the output of the amplifier to the input of the amplifier to initiate and sustain an oscillating condition, and wherein the impedance transformation network is configured to protect the input of the amplifier from a destructive feedback signal. One example of the oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

  15. Solution to Exam 1

    E-Print Network [OSTI]

    2012-02-07T23:59:59.000Z

    Page 1 .... Solution Letting what is under the square root be u, i.e., u = x3 + 2x2 + 1, we get du. 3x2 + 4x. = dx. Also remeber to ... about the city named Lafayette in Contra Costa County in California after t seconds from now (t = 0) .... (b) (6 points) Find the consumers' surplus at equilibrium (DON'T approximate the an- swer!).

  16. A MultiPhase Power Flow Model for Grid Analysis A. P. Sakis Meliopoulos

    E-Print Network [OSTI]

    A MultiPhase Power Flow Model for µµµµGrid Analysis A. P. Sakis Meliopoulos School of Electrical multiphase power flow analysis method that provides exact solution to the operation of the µGrid under steady

  17. THE HELIUM ABUNDANCE IN POLAR CORONAL HOLES AND THE FAST SOLAR WIND

    SciTech Connect (OSTI)

    Byhring, H. S., E-mail: hanne-sigrun.byhring@uit.no [Department of Physics and Technology, University of Tromsoe, No-9037 Tromsoe (Norway)

    2011-09-10T23:59:59.000Z

    I have studied the helium abundance in polar coronal holes and the fast solar wind using a time-dependent numerical model for the hydrogen-helium solar wind that spans the mid-to-upper chromosphere, transition region, corona, and solar wind. The model calculates the particle density, flow velocity, parallel and perpendicular temperature, and heat flux for all particle species simultaneously. The focus is on (1) the coronal/solar wind helium abundance as a function of the total magnetic field expansion and (2) the coronal abundance enhancements resulting from low helium heating rates. It is shown that the magnetic field expansion factor may be important in the determination of the solar wind helium abundance and that this can be understood in terms of gravitational settling in the chromosphere. I find that a total magnetic field expansion factor of about 20 is consistent with the observed helium abundance in the solar wind. Furthermore, it is demonstrated that existing observations, both spectroscopic observations of the corona and in situ observations in the solar wind, are compatible with helium abundance enhancements in the corona. For proton-electron plasma properties in accordance with observations, the coronal helium abundance enhancements occur in the region 1.2-2 R{sub sun}.

  18. On the maximum value of the cosmic abundance of oxygen and the oxygen yield

    E-Print Network [OSTI]

    L. S. Pilyugin; T. X. Thuan; J. M. Vilchez

    2007-01-11T23:59:59.000Z

    We search for the maximum oxygen abundance in spiral galaxies. Because this maximum value is expected to occur in the centers of the most luminous galaxies, we have constructed the luminosity - central metallicity diagram for spiral galaxies, based on a large compilation of existing data on oxygen abundances of HII regions in spiral galaxies. We found that this diagram shows a plateau at high luminosities (-22.3 oxygen abundance 12+log(O/H) ~ 8.87. This provides strong evidence that the oxygen abundance in the centers of the most luminous metal-rich galaxies reaches the maximum attainable value of oxygen abundance. Since some fraction of the oxygen (about 0.08 dex) is expected to be locked into dust grains, the maximum value of the true gas+dust oxygen abundance in spiral galaxies is 12+log(O/H) ~ 8.95. This value is a factor of ~ 2 higher than the recently estimated solar value. Based on the derived maximum oxygen abundance in galaxies, we found the oxygen yield to be about 0.0035, depending on the fraction of oxygen incorporated into dust grains.

  19. Quicksilver Solutions of a q-difference first Painlevé equation

    E-Print Network [OSTI]

    Nalini Joshi

    2014-07-07T23:59:59.000Z

    In this paper, we present new, unstable solutions, which we call quicksilver solutions, of a $q$-difference Painlev\\'e equation in the limit as the independent variable approaches infinity. The specific equation we consider in this paper is a discrete version of the first Painlev\\'e equation ($q\\Pon$), whose phase space (space of initial values) is a rational surface of type $A_7^{(1)}$. We describe four families of almost stationary behaviours, but focus on the most complicated case, which is the vanishing solution. We derive this solution's formal power series expansion, describe the growth of its coefficients and show that, while the series is divergent, there exist true analytic solutions asymptotic to such a series in a certain $q$-domain. The method, while demonstrated for $q\\Pon$, is also applicable to other $q$-difference Painlev\\'e equations.

  20. Non-LTE metal abundances in V652 Her and HD144941

    E-Print Network [OSTI]

    N. Przybilla; M. F. Nieva; U. Heber; C. S. Jeffery

    2005-12-06T23:59:59.000Z

    Two evolutionary scenarios are proposed for the formation of extreme helium stars: a post-AGB star suffering from a late thermal pulse, or the merger of two white dwarfs. An identification of the evolutionary channel for individual objects has to rely on surface abundances. We present preliminary results from a non-LTE analysis of CNO, Mg and S for two unique objects, V652 Her and HD144941. Non-LTE abundance corrections for these elements range from negligible values to ~0.7 dex. Non-LTE effects typically lead to systematic shifts in the abundances relative to LTE and reduce the uncertainties.

  1. Species composition, distribution, and seasonal abundance of macro-zooplankton in intake and discharge areas before and during early operation of the Cedar Bayou generating station

    E-Print Network [OSTI]

    Kalke, Richard D

    1972-01-01T23:59:59.000Z

    collections were made during the first and third weekends of each month. As of March I, 1970 collec- tions were made on alternate weekends for purposes of greater uni- formity. Generation of electric power and discharge of heated water by Unit 1, a 750 MW... for invertebrates while Middle Bay, Tabbs Bay and Cedar Bayou ranked in decreas1ng order. Factors thought to have caused differences in abundance of species and catch per effort between the areas studied were: (I) degree of pollution in each area, (2) amount...

  2. Designing AC Power Grids using Integer Linear Programming

    E-Print Network [OSTI]

    2011-02-18T23:59:59.000Z

    view of recent developments in integer linear programming, we revisit a less known .... optimal solution of the DC model was the minimum cost circuit of the network. ... Andersson, G.: Modelling and Analysis of Electric Power Systems (

  3. Integrating Variable Renewable Energy: Challenges and Solutions

    SciTech Connect (OSTI)

    Bird, L.; Milligan, M.; Lew, D.

    2013-09-01T23:59:59.000Z

    In the U.S., a number of utilities are adopting higher penetrations of renewables, driven in part by state policies. While power systems have been designed to handle the variable nature of loads, the additional supply-side variability and uncertainty can pose new challenges for utilities and system operators. However, a variety of operational and technical solutions exist to help integrate higher penetrations of wind and solar generation. This paper explores renewable energy integration challenges and mitigation strategies that have been implemented in the U.S. and internationally, including forecasting, demand response, flexible generation, larger balancing areas or balancing area cooperation, and operational practices such as fast scheduling and dispatch.

  4. A Comparison of the AC and DC Power Flow Models for LMP Calculations

    E-Print Network [OSTI]

    A Comparison of the AC and DC Power Flow Models for LMP Calculations Thomas J. Overbye, Xu Cheng power flow model for LMP-based market calculations. The paper first provides a general discussion of balanced, three phase, electric power transmission networks is through the solution of the power flow. From

  5. LQ Optimal Control of Wind Turbines in Hybrid Power Systems N.A. Cutululis1

    E-Print Network [OSTI]

    LQ Optimal Control of Wind Turbines in Hybrid Power Systems N.A. Cutululis1 , H. Bindner1 , I power systems represent a viable solution for rural electrification. One of the most important aspects taken into account for the design of a wind ­ diesel power system is the wind power penetration, which

  6. Review: Greenhouse Solutions with Sustainable Energy

    E-Print Network [OSTI]

    Hamilton-Smith, Elery

    2009-01-01T23:59:59.000Z

    Solutions with Sustainable Energy By Mark DiesendorfSolutions with Sustainable Energy. Sydney, NSW: University

  7. Beam-powered lunar rover design

    SciTech Connect (OSTI)

    Dagle, J.E.; Coomes, E.P.; Antoniak, Z.I.; Bamberger, J.A.; Bates, J.M.; Chiu, M.A.; Dodge, R.E.; Wise, J.A.

    1992-03-01T23:59:59.000Z

    Manned exploration of our nearest neighbors in the solar systems is the primary goal of the Space Exploration Initiative (SEI). An integral part of any manned lunar or planetary outpost will be a system for manned excursions over the surface of the planet. This report presents a preliminary design for a lunar rover capable of supporting four astronauts on long-duration excursions across the lunar landscape. The distinguishing feature of this rover design is that power is provided to rover via a laser beam from an independent orbiting power satellite. This system design provides very high power availability with minimal mass on the rover vehicle. With this abundance of power, and with a relatively small power-system mass contained in the rover, the vehicle can perform an impressive suite of mission-related activity. The rover might be used as the first outpost for the lunar surface (i.e., a mobile base). A mobile base has the advantage of providing extensive mission activities without the expense of establishing a fixed base. This concept has been referred to as Rove First.'' A manned over, powered through a laser beam, has been designed for travel on the lunar surface for round-trip distances in the range of 1000 km, although the actual distance traveled is not crucial since the propulsion system does not rely on energy storage. The life support system can support a 4-person crew for up to 30 days, and ample power is available for mission-related activities. The 8000-kg rover has 30 kW of continuous power available via a laser transmitter located at the Earth-moon L1 libration point, about 50,000 km above the surface of the moon. This rover, which is designed to operate in either day or night conditions, has the flexibility to perform a variety of power-intensive missions. 24 refs.

  8. Beam-powered lunar rover design

    SciTech Connect (OSTI)

    Dagle, J.E.; Coomes, E.P.; Antoniak, Z.I.; Bamberger, J.A.; Bates, J.M.; Chiu, M.A.; Dodge, R.E.; Wise, J.A.

    1992-03-01T23:59:59.000Z

    Manned exploration of our nearest neighbors in the solar systems is the primary goal of the Space Exploration Initiative (SEI). An integral part of any manned lunar or planetary outpost will be a system for manned excursions over the surface of the planet. This report presents a preliminary design for a lunar rover capable of supporting four astronauts on long-duration excursions across the lunar landscape. The distinguishing feature of this rover design is that power is provided to rover via a laser beam from an independent orbiting power satellite. This system design provides very high power availability with minimal mass on the rover vehicle. With this abundance of power, and with a relatively small power-system mass contained in the rover, the vehicle can perform an impressive suite of mission-related activity. The rover might be used as the first outpost for the lunar surface (i.e., a mobile base). A mobile base has the advantage of providing extensive mission activities without the expense of establishing a fixed base. This concept has been referred to as ``Rove First.`` A manned over, powered through a laser beam, has been designed for travel on the lunar surface for round-trip distances in the range of 1000 km, although the actual distance traveled is not crucial since the propulsion system does not rely on energy storage. The life support system can support a 4-person crew for up to 30 days, and ample power is available for mission-related activities. The 8000-kg rover has 30 kW of continuous power available via a laser transmitter located at the Earth-moon L1 libration point, about 50,000 km above the surface of the moon. This rover, which is designed to operate in either day or night conditions, has the flexibility to perform a variety of power-intensive missions. 24 refs.

  9. Is Nuclear Energy the Solution?

    E-Print Network [OSTI]

    Saier, Milton H.; Trevors, Jack T.

    2010-01-01T23:59:59.000Z

    wind power and other renewable technologies, combined with energy efficiency and conservation can be more cost

  10. Space-based solar power generation using a distributed network of satellites and methods for efficient space power transmission

    E-Print Network [OSTI]

    McLinko, Ryan M.

    Space-based solar power (SSP) generation is being touted as a solution to our ever-increasing energy consumption and dependence on fossil fuels. Satellites in Earth's orbit can capture solar energy through photovoltaic ...

  11. Bearwall Energy Efficient Solutions

    E-Print Network [OSTI]

    Sovero,M.

    2014-01-01T23:59:59.000Z

    CATEE Conference November 20, 2014 ENERGY EFFICIENT SOLUTIONS ESL-KT-14-11-06 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Brief History of Bearwall… Who We Are: ? Manuel Sovero ? Luis Osorio Energy Conservation... Experience: ESL-KT-14-11-06 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Energy Programs… ESL-KT-14-11-06 CATEE 2014: Clean Air Through Efficiency Conference, Dallas, Texas Nov. 18-20 Bearwall Methodology… Introduction...

  12. Building America Solution Center

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof Energy Future ofHydronic Heating inOctober 2011 | DepartmentSolution

  13. Oxygen abundances in dwarf irregular galaxies and the metallicity - luminosity relationship

    E-Print Network [OSTI]

    L. S. Pilyugin

    2001-05-21T23:59:59.000Z

    The low-luminosity dwarf irregular galaxies are considered. The oxygen abundances in HII regions of dwarf irregular galaxies were recalculated from published spectra through the recently suggested P - method. It has been found that the metallicity of low-luminosity dwarf irregular galaxies, with a few exceptions, correlates well with galaxy luminosity. The dispersion of oxygen abundances around the metallicity - luminosity relationship increases with decreasing of galaxy luminosity, as was found by Richer and McCall (1995). No relationship between the oxygen abundance and the absolute magnitude in the blue band for irregular galaxies obtained by Hidalgo-Gamez and Olofsson (1998) can be explained by the large uncertainties in the oxygen abundances derived through the Te - method, that in turn can be explained by the large uncertainties in the measurements of the strengths of the weak oxygen line [OIII]4363 used in the Te - method.

  14. acid-base transporter abundance: Topics by E-print Network

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

    Page Last Page Topic Index 1 Transport Phenomena and Light Element Abundances in the Sun and Solar Type Stars Astrophysics (arXiv) Summary: The observations of light elements...

  15. Spatial pattern and temporal dynamics of northern bobwhite abundance and agricultural landuse, and potential casual factors 

    E-Print Network [OSTI]

    Okay, Atiye Zeynep

    2006-04-12T23:59:59.000Z

    There was a long-term decline in northern bobwhite (Colinus virginianus, NBW) abundance since the 1920s, based on the Christmas Bird Count (CBC) data, but with substantial spatial and temporal variations across its range. ...

  16. Monte Carlo Method for Calculating Oxygen Abundances and Their Uncertainties from Strong-Line Flux Measurements

    E-Print Network [OSTI]

    Bianco, Federica B; Oh, Seung Man; Fierroz, David; Liu, Yuqian; Kewley, Lisa; Graur, Or

    2015-01-01T23:59:59.000Z

    We present the open-source Python code pyMCZ that determines oxygen abundance and its distribution from strong emission lines in the standard metallicity scales, based on the original IDL code of Kewley & Dopita (2002) with updates from Kewley & Ellison (2008), and expanded to include more recently developed scales. The standard strong-line diagnostics have been used to estimate the oxygen abundance in the interstellar medium through various emission line ratios in many areas of astrophysics, including galaxy evolution and supernova host galaxy studies. We introduce a Python implementation of these methods that, through Monte Carlo (MC) sampling, better characterizes the statistical reddening-corrected oxygen abundance confidence region. Given line flux measurements and their uncertainties, our code produces synthetic distributions for the oxygen abundance in up to 13 metallicity scales simultaneously, as well as for E(B-V), and estimates their median values and their 66% confidence regions. In additi...

  17. Influences of vegetation characteristics and invertebrate abundance of Rio Grande wild turkey populations, Edwards Plateau, Texas

    E-Print Network [OSTI]

    Randel, Charles Jack

    2005-02-17T23:59:59.000Z

    Since 1970, Rio Grande wild turkey (Meleagris gallapavo intermedia) numbers in the southern region of the Edwards Plateau of Texas have been declining. Nest-site characteristics and invertebrate abundance were hypothesized as limiting wild turkey...

  18. Environmental factors affecting planktonic foraminifera abundance and distribution in the Northeast Gulf of Mexico

    E-Print Network [OSTI]

    Ravula, Sharath Reddy

    2005-08-29T23:59:59.000Z

    shift in the species abundances and depths occurred between eddies. Species occurred where physical factors were compatible with conditions and feeding opportunities they were adapted to. Three species pink and white Globigerinoides ruber...

  19. Abundance analysis of SB2 binary stars with HgMn primaries

    E-Print Network [OSTI]

    T. Ryabchikova

    1998-05-06T23:59:59.000Z

    We present a short review of the abundances in the atmospheres of SB2 systems with Mercury-Manganese (HgMn) primaries. Up to now a careful study has been made for both components of 8 out of 17 known SB2 binaries with orbital periods shorter than 100 days and mass ratio ranging from 1.08 to 2.2. For all eight systems we observe a lower Mn abundance in the secondary's atmospheres than in the primary's. Significant difference in the abundances is also found for some peculiar elements such as Ga, Xe, Pt. All secondary stars with effective temperatures less than 10000 K show abundance characteristics typical of the metallic-line stars.

  20. Using automatically-triggered cameras to monitor and estimate bobcat abundance

    E-Print Network [OSTI]

    Heilbrun, Richard David

    2002-01-01T23:59:59.000Z

    triggered cameras as part of a mark-recapture study design. I tested the assumptions that bobcats were individually identifiable by their natural markings and that information obtained from camera surveys can contribute to abundance estimates from mark...

  1. Reef Habitats in the Middle Atlantic Bight: Abundance, Distribution, Associated Biological

    E-Print Network [OSTI]

    abundance of fishery resources are in- and Biggs, 1988; Poppe et al., 1994). fluenced by physical and other can Stumf and Biggs, 1988; Poppe et al., lead to a better understanding of how 1994; NOAA National

  2. Earth abundant materials for high efficiency heterojunction thin film solar cells

    E-Print Network [OSTI]

    Buonassisi, Tonio

    We investigate earth abundant materials for thin-film solar cells that can meet tens of terawatts level deployment potential. Candidate materials are identified by combinatorial search, large-scale electronic structure ...

  3. Coronal and Solar Wind Elemental Abundances J. C. Raymond , J. E. Mazur + , F. Allegrini , E. Antonucci # , G. Del Zanna ,

    E-Print Network [OSTI]

    Del Zanna, Giulio

    Coronal and Solar Wind Elemental Abundances J. C. Raymond #3; , J. E. Mazur + , F. Allegrini #3, Johns Hopkins Road, Laurel, MD 20723 USA k Naval Research Laboratory, Washington, DC USA ++ MIT, Room 37. Coronal elemental abundances, as compared with abundances in the solar wind and solar energetic particles

  4. Petrologic mapping of the Moon using Fe, Mg, and Al abundances A.A. Berezhnoy a,*, N. Hasebe a

    E-Print Network [OSTI]

    Berezhnoi, Aleksei A.

    Petrologic mapping of the Moon using Fe, Mg, and Al abundances A.A. Berezhnoy a,*, N. Hasebe a , M for the presence of polar lunar hydrogen. Using Mg, Fe, and Al abundances, petrologic maps containing information: Moon; Maps of elemental abundances; Petrology; End-member rocks; Chemistry of lunar polar regions; Rock

  5. The N/O abundance ratio in the lowest-metallicity blue compact dwarf galaxies

    E-Print Network [OSTI]

    Y. Izotov; F. Chaffee; C. Foltz; K. Fricke; R. Green; N. Guseva; K. Noeske; P. Papaderos; T. Thuan

    2001-09-27T23:59:59.000Z

    The results of the N/O abundance determination in a sample of low-metallicity blue compact dwarf (BCD) galaxies based on new spectroscopic observations with large telescopes (Keck, VLT, MMT, 4m KPNO) are presented. We show that the N/O abundance ratio is constant at lowest metallicities < Zsun/20, confirming previous findings and strongly supporting the origin of nitrogen as a primary element.

  6. A New Technique for Determining Europium Abundances in Solar-Metallicity Stars

    E-Print Network [OSTI]

    Peek, Kathryn M G

    2009-01-01T23:59:59.000Z

    We present a new technique for measuring the abundance of europium, a representative r-process element, in solar-metallicity stars. Our algorithm compares LTE synthetic spectra with high-resolution observational spectra using a chi-square-minimization routine. The analysis is fully automated, and therefore allows consistent measurement of blended lines even across very large stellar samples. We compare our results with literature europium abundance measurements and find them to be consistent; we also find our method generates smaller errors.

  7. Title: Experimental Platform for Novel Distributed Microgrids Control Solutions

    E-Print Network [OSTI]

    Johnson, Eric E.

    Title: Experimental Platform for Novel Distributed Microgrids Control Solutions Principal Investigator: Wenxin Liu Sponsor: U.S. Department of Defense Office of Naval Research Summary: Microgrid can, and can operate autonomously without connecting to power grid. The microgrid concept is a big step toward

  8. Smoothness of generalized solutions for higher-order elliptic equations

    E-Print Network [OSTI]

    Fiedler, Bernold

    of nonlocal problems with transformations mapping the boundary inside the closure of a domain were studied. Further investigation of elliptic problems with transformations mapping a boundary onto itself as well, solutions of nonlocal problems can have power-law singularities near some points of the boundary even

  9. The Solar Solution By Garion Bienn and Chris

    E-Print Network [OSTI]

    Generation - A Comparative View of Technologies, Costs and Environmental Impact. German Aerospace Research Induced Convective Flows for Power Generation. Journal of Solar Energy Engineering 127 (1): 117-124. doiThe Solar Solution By Garion Bienn and Chris Eudaily #12;Introduction - our project Construct

  10. Energy Storage for the Power Grid

    SciTech Connect (OSTI)

    Imhoff, Carl; Vaishnav, Dave

    2014-07-01T23:59:59.000Z

    The iron vanadium redox flow battery was developed by researchers at Pacific Northwest National Laboratory as a solution to large-scale energy storage for the power grid. This technology provides the energy industry and the nation with a reliable, stable, safe, and low-cost storage alternative for a cleaner, efficient energy future.

  11. Chemical Abundances in AGN Environment: X-Ray/UV Campaign on the MRK 279 Outflow

    E-Print Network [OSTI]

    Nahum Arav; Jack R. Gabel; Kirk T. Korista; Jelle S. Kaastra; Gerard A. Kriss; Ehud Behar; Elisa Costantini; C. Martin Gaskell; Ari Laor; Nalaka Kodituwakku; Daniel Proga; Masao Sako; Jennifer E. Scott; Katrien C. Steenbrugge

    2006-11-29T23:59:59.000Z

    We present the first reliable determination of chemical abundances in an AGN outflow. The abundances are extracted from the deep and simultaneous FUSE and HST/STIS observations of Mrk 279. This data set is exceptional for its high signal-to-noise, unblended doublet troughs and little Galactic absorption contamination. These attributes allow us to solve for the velocity-dependent covering fraction, and therefore obtain reliable column densities for many ionic species. For the first time we have enough such column densities to simultaneously determine the ionization equilibrium and abundances in the flow. Our analysis uses the full spectral information embedded in these high-resolution data. Slicing a given trough into many independent outflow elements yields the extra constraints needed for a physically meaningful abundances determination. We find that relative to solar the abundances in the Mrk 279 outflow are (linear scaling): carbon 2.2+/-0.7, nitrogen 3.5+/-1.1 and oxygen 1.6+/-0.8. Our UV-based photoionization and abundances results are in good agreement with the independent analysis of the simultaneous Mrk 279 X-ray spectra. This is the best agreement between the UV and X-ray analyses of the same outflow to date.

  12. Abundances, Stellar Parameters, and Spectra From the SDSS-III/APOGEE Survey

    E-Print Network [OSTI]

    Holtzman, Jon A; Johnson, Jennifer A; Prieto, Carlos Allende; Anders, Friedrich; Andrews, Brett; Beers, Timothy C; Bizyaev, Dmitry; Blanton, Michael R; Bovy, Jo; Carrera, Ricardo; Cunha, Katia; Eisenstein, Daniel J; Feuillet, Diane; Frinchaboy, Peter M; Galbraith-Frew, Jessica; Perez, Ana E Garcia; Hernandez, D Anibal Garcia; Hasselquist, Sten; Hayden, Michael R; Hearty, Fred R; Ivans, Inese; Majewski, Steven R; Martell, Sarah; Meszaros, Szabolcs; Muna, Demitri; Nidever, David L; Nguyen, Duy Cuong; O'Connell, Robert W; Pan, Kaike; Pinsonneault, Marc; Robin, Annie C; Schiavon, Ricardo P; Shane, Neville; Sobeck, Jennifer; Smith, Verne V; Troup, Nicholas; Weinberg, David H; Wilson, John C; Wood-Vasey, W M; Zamora, Olga; Zasowski, Gail

    2015-01-01T23:59:59.000Z

    The SDSS-III/APOGEE survey operated from 2011-2014 using the APOGEE spectrograph, which collects high-resolution (R~22,500), near-IR (1.51-1.70 microns) spectra with a multiplexing (300 fiber-fed objects) capability. We describe the survey data products that are publicly available, which include catalogs with radial velocity, stellar parameters, and 15 elemental abundances for over 150,000 stars, as well as the more than 500,000 spectra from which these quantities are derived. Calibration relations for the stellar parameters (Teff, log g, [M/H], [alpha/M]) and abundances (C, N, O, Na, Mg, Al, Si, S, K, Ca, Ti, V, Mn, Fe, Ni) are presented and discussed. The internal scatter of the abundances within clusters indicates that abundance precision is generally between 0.05 and 0.09 dex across a broad temperature range; within more limited ranges and at high S/N, it is smaller for some elemental abundances. We assess the accuracy of the abundances using comparison of mean cluster metallicities with literature values...

  13. Photovoltaic Power Generation in the Stellar Environments

    E-Print Network [OSTI]

    T. E. Girish; S. Aranya

    2010-12-03T23:59:59.000Z

    In this paper we have studied the problem of photovoltaic power generation near selected stars in the solar neighborhood. The nature of the optical radiation from a star will depend on its luminosity,HR classification and spectral characteristics. The solar celloperation in the habitable zones of the stars is similar to AM1.0 operation near earth.Thecurrent space solar cell technology can be adopted for power generation near G,K and Mtype stars. Silicon solar cells with good near IR response are particularly suitable in theenvironments of M type stars which are most abundant in the universe. . Photovoltaicpower generation near binary stars like Sirius and Alpha Centauri is also discussed.

  14. Personnel Grounding and Safety: Issues and Solutions Related to Servicing Optical Fiber

    E-Print Network [OSTI]

    Personnel Grounding and Safety: Issues and Solutions Related to Servicing Optical Fiber Telecommunication Circuits in Optical Ground Wire (OPGW) Final Project Report Power Systems Engineering Research to Servicing Optical Fiber Telecommunication Circuits in Optical Ground Wire (OPGW) Final Project Report

  15. Technical solutions to nonproliferation challenges

    SciTech Connect (OSTI)

    Satkowiak, Lawrence [Director, Nonproliferation, Safeguards and Security Programs, Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States)

    2014-05-09T23:59:59.000Z

    The threat of nuclear terrorism is real and poses a significant challenge to both U.S. and global security. For terrorists, the challenge is not so much the actual design of an improvised nuclear device (IND) but more the acquisition of the special nuclear material (SNM), either highly enriched uranium (HEU) or plutonium, to make the fission weapon. This paper provides two examples of technical solutions that were developed in support of the nonproliferation objective of reducing the opportunity for acquisition of HEU. The first example reviews technologies used to monitor centrifuge enrichment plants to determine if there is any diversion of uranium materials or misuse of facilities to produce undeclared product. The discussion begins with a brief overview of the basics of uranium processing and enrichment. The role of the International Atomic Energy Agency (IAEA), its safeguard objectives and how the technology evolved to meet those objectives will be described. The second example focuses on technologies developed and deployed to monitor the blend down of 500 metric tons of HEU from Russia's dismantled nuclear weapons to reactor fuel or low enriched uranium (LEU) under the U.S.-Russia HEU Purchase Agreement. This reactor fuel was then purchased by U.S. fuel fabricators and provided about half the fuel for the domestic power reactors. The Department of Energy established the HEU Transparency Program to provide confidence that weapons usable HEU was being blended down and thus removed from any potential theft scenario. Two measurement technologies, an enrichment meter and a flow monitor, were combined into an automated blend down monitoring system (BDMS) and were deployed to four sites in Russia to provide 24/7 monitoring of the blend down. Data was downloaded and analyzed periodically by inspectors to provide the assurances required.

  16. The abundance of presolar grains in comet 81P/WILD 2

    SciTech Connect (OSTI)

    Floss, Christine; Stadermann, Frank J.; Ong, W. J. [Laboratory for Space Sciences, Physics Department, Washington University, 1 Brookings Drive, St. Louis, MO 63130 (United States)] [Laboratory for Space Sciences, Physics Department, Washington University, 1 Brookings Drive, St. Louis, MO 63130 (United States); Kearsley, Anton T. [Impacts and Astromaterials Research Centre, Science Facilities, Natural History Museum, London SW7 5BD (United Kingdom)] [Impacts and Astromaterials Research Centre, Science Facilities, Natural History Museum, London SW7 5BD (United Kingdom); Burchell, Mark J., E-mail: floss@wustl.edu [Centre for Astrophysics and Planetary Sciences, School of Physical Sciences, University of Kent, Canterbury, Kent CT2 7NH (United Kingdom)

    2013-02-15T23:59:59.000Z

    We carried out hypervelocity impact experiments in order to test the possibility that presolar grains are preferentially destroyed during impact of the comet 81P/Wild 2 samples into the Stardust Al foil collectors. Powdered samples of the ungrouped carbonaceous chondrite Acfer 094 were shot at 6 km s{sup -1} into Stardust flight spare Al foil. Craters from the Acfer 094 test shots, as well as ones from the actual Stardust cometary foils, were analyzed by NanoSIMS ion imaging to search for presolar grains. We found two O-rich presolar grains and two presolar SiC grains in the Acfer 94 test shots, with measured abundances in the foils of 4 and 5 ppm, respectively, significantly lower than the amount of presolar grains actually present in this meteorite. Based on known abundances of these phases in Acfer 094, we estimate a loss of over 90% of the O-rich presolar grains; the fraction of SiC lost is lower, reflecting its higher resistance to destruction. In the Stardust cometary foils, we identified four O-rich presolar grains in 5000 {mu}m{sup 2} of crater residue. Including a presolar silicate grain found by Leitner et al., the overall measured abundance of O-rich presolar grains in Wild 2 is {approx}35 ppm. No presolar SiC has been found in the foil searches, although one was identified in the aerogel samples. Based on the known abundances of presolar silicates and oxides in Acfer 094, we can calculate the pre-impact abundances of these grains in the Stardust samples. Our calculations indicate initial abundances of 600-830 ppm for O-rich presolar grains. Assuming a typical diameter of {approx}300 nm for SiC suggests a presolar SiC abundance of {approx}45 ppm. Analyses of the Stardust samples indicated early on that recognizable presolar components were not particularly abundant, an observation that was contrary to expectations that the cometary material would, like interplanetary dust particles, be dominated by primitive materials from the early solar system (including abundant presolar grains), which had remained essentially unaltered over solar system history in the cold environment of the Kuiper Belt. Our work shows that comet Wild 2, in fact, does contain more presolar grains than measurements on the Stardust samples suggest, with abundances similar to those observed in primitive IDPs.

  17. New Rare Earth Element Abundance Distributions for the Sun and Five r-Process-Rich Very Metal-Poor Stars

    E-Print Network [OSTI]

    Sneden, Christopher; Cowan, John J; Ivans, Inese I; Hartog, Elizabeth A Den

    2009-01-01T23:59:59.000Z

    We have derived new abundances of the rare-earth elements Pr, Dy, Tm, Yb, and Lu for the solar photosphere and for five very metal-poor, neutron-capture r-process-rich giant stars. The photospheric values for all five elements are in good agreement with meteoritic abundances. For the low metallicity sample, these abundances have been combined with new Ce abundances from a companion paper, and reconsideration of a few other elements in individual stars, to produce internally-consistent Ba, rare-earth, and Hf (56<= Z <= 72) element distributions. These have been used in a critical comparison between stellar and solar r-process abundance mixes.

  18. 2010 Water & Aqueous Solutions

    SciTech Connect (OSTI)

    Dor Ben-Amotz

    2010-08-13T23:59:59.000Z

    Water covers more than two thirds of the surface of the Earth and about the same fraction of water forms the total mass of a human body. Since the early days of our civilization water has also been in the focus of technological developments, starting from converting it to wine to more modern achievements. The meeting will focus on recent advances in experimental, theoretical, and computational understanding of the behavior of the most important and fascinating liquid in a variety of situations and applications. The emphasis will be less on water properties per se than on water as a medium in which fundamental dynamic and reactive processes take place. In the following sessions, speakers will discuss the latest breakthroughs in unraveling these processes at the molecular level: Water in Solutions; Water in Motion I and II; Water in Biology I and II; Water in the Environment I and II; Water in Confined Geometries and Water in Discussion (keynote lecture and poster winners presentations).

  19. Energy Storage for Power Systems Applications: A Regional Assessment for the Northwest Power Pool (NWPP)

    SciTech Connect (OSTI)

    Kintner-Meyer, Michael CW; Balducci, Patrick J.; Jin, Chunlian; Nguyen, Tony B.; Elizondo, Marcelo A.; Viswanathan, Vilayanur V.; Guo, Xinxin; Tuffner, Francis K.

    2010-04-01T23:59:59.000Z

    Wind production, which has expanded rapidly in recent years, could be an important element in the future efficient management of the electric power system; however, wind energy generation is uncontrollable and intermittent in nature. Thus, while wind power represents a significant opportunity to the Bonneville Power Administration (BPA), integrating high levels of wind resources into the power system will bring great challenges to generation scheduling and in the provision of ancillary services. This report addresses several key questions in the broader discussion on the integration of renewable energy resources in the Pacific Northwest power grid. More specifically, it addresses the following questions: a) how much total reserve or balancing requirements are necessary to accommodate the simulated expansion of intermittent renewable energy resources during the 2019 time horizon, and b) what are the most cost effective technological solutions for meeting load balancing requirements in the Northwest Power Pool (NWPP).

  20. SGTE Power | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries Pvt Ltd Jump to:RoscommonSBY Solutions Jump to: navigation,SEMASSSESSGTE Power Jump

  1. Starfire - a commercial tokamak fusion power reactor concept

    SciTech Connect (OSTI)

    Baker, C.C.; Abdou, M.A.; DeFreece, D.A.; Trachsel, C.A.; Graumann, D.; Kokoszenski, J.

    1980-01-01T23:59:59.000Z

    The purpose of the STARFIRE study is to develop a design concept for a commercial tokamak fusion electric power plant based on the deuterium/tritium/lithium-fuel cycle. The key technical objective is to develop an attractive embodiment of the tokamak as a power reactor consistent with credible engineering solutions to design problems. 1 ref.

  2. An investigation of simple nonsmooth power system models

    SciTech Connect (OSTI)

    Mantri, R.; Venkatasubramanian, V.; Saberi, A. [Washington State Univ., Pullman, WA (United States)

    1994-12-31T23:59:59.000Z

    Recently new notions of solutions and equilibrium points have been proposed for analyzing nonsmooth system descriptions. This paper observes certain new phenomena in simple nonsmooth power system models presenting a preliminary analysis. The results include an investigation of new Hopf-like bifurcations related to the birth of limit cycles in two dimensional non-Lipschitzian power system models.

  3. USING SAT-BASED TECHNIQUES IN LOW POWER STATE ASSIGNMENT

    E-Print Network [OSTI]

    Aloul, Fadi

    and basis for further exploration. Keywords: State assignment; power; integer linear programming; Boolean¯ability and Integer Linear Programming (ILP) methods in ¯nding an optimized solution. We formulate the problem as a 0USING SAT-BASED TECHNIQUES IN LOW POWER STATE ASSIGNMENT ¤ ASSIM SAGAHYROON and FADI A. ALOUL

  4. Power Grid Voltage Integrity Verification Department of ECE

    E-Print Network [OSTI]

    Najm, Farid N.

    Power Grid Voltage Integrity Verification Maha Nizam Department of ECE University of Toronto devgan@magma-da.com ABSTRACT Full-chip verification requires one to check if the power grid is safe, i.e., if the voltage drop on the grid does not exceed a cer- tain threshold. The traditional simulation-based solution

  5. LIFE Power Plant Fusion Power Associates

    E-Print Network [OSTI]

    LIFE Power Plant Fusion Power Associates December 14, 2011 Mike Dunne LLNL #12;NIf-1111-23714.ppt LIFE power plant 2 #12;LIFE delivery timescale NIf-1111-23714.ppt 3 #12;Timely delivery is enabled dpa) § Removes ion threat and mitigates x-ray threat ­ allows simple steel piping § No need

  6. Solar powered desalination system

    E-Print Network [OSTI]

    Mateo, Tiffany Alisa

    2011-01-01T23:59:59.000Z

    are many solar photovoltaic power plants internationally andUSA, Blythe, CA Solar electric power plant, Blythe USA, SanTX Blue Wing solar electric power plant USA, Jacksonville,

  7. Solar powered desalination system

    E-Print Network [OSTI]

    Mateo, Tiffany Alisa

    2011-01-01T23:59:59.000Z

    of the electrical power output to the solar power input), aSolar Energy Calculator using Google Maps 23 Table 1.24: PV System Power Production Average Daily Irradiance (kWh/m2) Instillation Efficiency Labeled Efficiency Output

  8. High Dispersion Spectroscopy of Solar-type Superflare Stars. III. Lithium Abundances

    E-Print Network [OSTI]

    Honda, Satoshi; Maehara, Hiroyuki; Notsu, Shota; Shibayama, Takuya; Nogami, Daisaku; Shibata, Kazunari

    2015-01-01T23:59:59.000Z

    We report on the abundance analysis of Li in solar-type (G-type main sequence) superflare stars which were found by the analysis of Kepler photometric data. Li is a key element to understand the evolution of the stellar convection zone which reflects the age of solar-type stars. We performed the high dispersion spectroscopy of solar-type superflare stars with Subaru/HDS, and confirmed that 34 stars show no evidence of binarity in our previous study. In this study, we derived the Li abundances of these 34 objects. We investigate correlations of Li abundance with stellar atmospheric parameters, rotational velocity, and superflare activities to understand the nature of superflare stars and the possibility of the nucleosynthesis of Li by superflares. We confirm the large dispersion in the Li abundance, and the correlation with stellar parameters is not seen. As compared with the Li abundance in Hyades cluster which is younger than the Sun, it is suggested that half of the observed stars are younger than Hyades cl...

  9. Oxygen abundances in G- and F-type stars from HARPS

    E-Print Network [OSTI]

    de Lis, S Bertran; Adibekyan, V Zh; Santos, N C; Sousa, S G

    2015-01-01T23:59:59.000Z

    We present a detailed and uniform study of oxygen abundance from two different oxygen lines at 6158$\\AA$ and 6300$\\AA$ in a large sample of solar-type stars. The results are used to check the behaviour of these spectral lines as oxygen abundance indicators and to study the evolution of oxygen in thick and thin disk populations of the Galaxy. Equivalent width measurements were carried out for the [OI]~6158$\\AA$ and OI~6300$\\AA$ lines. LTE abundances were obtained from these two lines in 610 and 535 stars, respectively. We were able to measure oxygen abundance from both indicators in 447 stars, enabling us, for the first time, to compare them in a uniform way. Careful error analysis has been performed. We found that oxygen abundances derived from the 6158$\\AA$ and 6300$\\AA$ lines agree to within 0.1dex in 58\\% of the stars in our sample, and this result improves for higher signal-to-noise values. We confirm an oxygen enhancement in stars of the thick disk, as has also been seen for other $\\alpha$-elements. The ...

  10. The Gaia-ESO Survey: Detailed Abundances in the Metal-poor Globular Cluster NGC 4372

    E-Print Network [OSTI]

    Roman, I San; Geisler, D; Villanova, S; Kacharov, N; Koch, A; Carraro, G; Tautvaišiene, G; Vallenari, A; Alfaro, E J; Bensby, T; Flaccomio, E; Francois, P; Korn, A J; Pancino, E; Recio-Blanco, A; Smiljanic, R; Bergemann, M; Costado, M T; Damiani, F; Heiter, U; Hourihane, A; Jofré, P; Lardo, C; de Laverny, P; Masseron, T; Morbidelli, L; Sbordone, L; Sousa, S G; Worley, C C; Zaggia, S

    2015-01-01T23:59:59.000Z

    We present the abundance analysis for a sample of 7 red giant branch stars in the metal-poor globular cluster NGC 4372 based on UVES spectra acquired as part of the Gaia-ESO Survey. This is the first extensive study of this cluster from high resolution spectroscopy. We derive abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, Fe, Cr, Ni, Y, Ba, and La. We find a metallicity of [Fe/H] = -2.19 $\\pm$ 0.03 and find no evidence for a metallicity spread. This metallicity makes NGC 4372 one of the most metal-poor galactic globular clusters. We also find an {\\alpha}-enhancement typical of halo globular clusters at this metallicity. Significant spreads are observed in the abundances of light elements. In particular we find a Na-O anti-correlation. Abundances of O are relatively high compared with other globular clusters. This could indicate that NGC 4372 was formed in an environment with high O for its metallicity. A Mg-Al spread is also present which spans a range of more than 0.5 dex in Al abundances. Na is correlated wit...

  11. NEON AND CNO ABUNDANCES FOR EXTREME HELIUM STARS-A NON-LTE ANALYSIS

    SciTech Connect (OSTI)

    Pandey, Gajendra [Indian Institute of Astrophysics, Bangalore, 560034 (India); Lambert, David L., E-mail: pandey@iiap.res.in, E-mail: dll@astro.as.utexas.edu [W.J. McDonald Observatory, University of Texas at Austin, Austin, TX 78712-1083 (United States)

    2011-02-01T23:59:59.000Z

    A non-LTE (NLTE) abundance analysis was carried out for three extreme helium stars (EHes): BD+10{sup 0} 2179, BD-9{sup 0} 4395, and LS IV+6{sup 0} 002, from their optical spectra with NLTE model atmospheres. NLTE TLUSTY model atmospheres were computed with H, He, C, N, O, and Ne treated in NLTE. Model atmosphere parameters were chosen from consideration of fits to observed He I line profiles and ionization equilibria of C and N ions. The program SYNSPEC was then used to determine the NLTE abundances for Ne as well as H, He, C, N, and O. LTE neon abundances from Ne I lines in the EHes: LSE 78, V1920 Cyg, HD 124448, and PV Tel, are derived from published models and an estimate of the NLTE correction applied to obtain the NLTE Ne abundance. We show that the derived abundances of these key elements, including Ne, are well matched with semi-quantitative predictions for the EHe resulting from a cold merger (i.e., no nucleosynthesis during the merger) of an He white dwarf with a C-O white dwarf.

  12. Clues on the evolution of abundance gradients and on AGB nucleosynthesis

    E-Print Network [OSTI]

    Stasinska, G; Bresolin, F; Tsamis, Yi

    2013-01-01T23:59:59.000Z

    We have obtained deep spectra of 26 planetary nebulae (PNe) and 9 compact HII regions in the nearby spiral galaxy NGC 300, and analyzed them together with those of the giant HII regions previously observed. We have determined the physical properties of all these objects and their He, N, O, Ne, S and Ar abundances in a consistent way. We find that, globally, compact HII regions have abundance ratios similar to those of giant HII regions, while PNe have systematically larger N/O ratios and similar Ne/O and Ar/O ratios. We demonstrate that the nitrogen enhancement in PNe cannot be only due to second dredge-up in the progenitor stars, since their initial masses are around 2--2.5\\,\\msun. An extra mixing process is required, perhaps driven by stellar rotation. Concerning the radial abundance distribution, PNe behave differently from HII regions: in the central part of the galaxy their average O/H abundance ratio is 0.15 dex smaller. Their abundance dispersion at any galactocentric radius is significantly larger tha...

  13. PowerPoint Presentation

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

    April 30, 2013, Santa Clara, CA 2 Outline * Introduction Power Electronics in Electric Drive Vehicles Automotive Power Electronics Module Operation Automotive...

  14. Concentrated Solar Thermoelectric Power

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

    CONCENTRATING SOLAR POWER PROGRAM REVIEW 2013 Concentrated Solar Thermoelectric Power Principal Investigator: Prof. Gang Chen Massachusetts Institute of Technology Cambridge, MA...

  15. TVA- Green Power Providers

    Broader source: Energy.gov [DOE]

    Tennessee Valley Authority (TVA) and participating power distributors of TVA power offer a performance-based incentive program to homeowners and businesses for the installation of renewable...

  16. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, N.; Ingersoll, D.

    1995-01-03T23:59:59.000Z

    Electrolytes are disclosed for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids. 7 figures.

  17. Electrolytes for power sources

    DOE Patents [OSTI]

    Doddapaneni, Narayan (Albuquerque, NM); Ingersoll, David (Albuquerque, NM)

    1995-01-01T23:59:59.000Z

    Electrolytes for power sources, particularly alkaline and acidic power sources, comprising benzene polysulfonic acids and benzene polyphosphonic acids or salts of such acids.

  18. Flex power perspectives of indirect power system control through...

    Open Energy Info (EERE)

    power perspectives of indirect power system control through dynamic power price (Smart Grid Project) Jump to: navigation, search Project Name Flex power perspectives of indirect...

  19. New Horizons Mission Powered by Space Radioisotope Power Systems...

    Energy Savers [EERE]

    New Horizons Mission Powered by Space Radioisotope Power Systems New Horizons Mission Powered by Space Radioisotope Power Systems January 30, 2008 - 6:47pm Addthis Artist's concept...

  20. Is Nuclear Energy the Solution?

    E-Print Network [OSTI]

    Saier, Milton H.; Trevors, Jack T.

    2010-01-01T23:59:59.000Z

    009-0270-y Is Nuclear Energy the Solution? Milton H. Saier &in the last 50 years, nuclear energy subsidies have totaledadministration, the Global Nuclear Energy Partnership (GNEP)

  1. Enhanced safeguards via solution monitoring

    SciTech Connect (OSTI)

    Burr, T.; Wangen, L.

    1996-09-01T23:59:59.000Z

    Solution monitoring is defined as the essentially continuous monitoring of solution level, density, and temperature in all tanks in the process that contain, or could contain, safeguards-significant quantities of nuclear material. This report describes some of the enhancements that solution monitoring could make to international safeguards. The focus is on the quantifiable benefits of solution monitoring, but qualitatively, solution monitoring can be viewed as a form of surveillance. Quantitatively, solution monitoring can in some cases improve diversion detection probability. For example, the authors show that under certain assumptions, solution monitoring can be used to reduce the standard deviation of the annual material balance, {sigma}{sub MB}, from approximately 17 kg to approximately 4 kg. Such reduction in {sigma}{sub MB} will not always be possible, as they discuss. However, in all cases, solution monitoring would provide assurance that the measurement error models are adequate so that one has confidence in his estimate of {sigma}{sub MB}. Some of the results in this report were generated using data that were simulated with prototype solution monitoring software that they are developing. An accompanying document describes that software.

  2. SOLUTION-PROCESSED INORGANIC ELECTRONICS

    E-Print Network [OSTI]

    Bakhishev, Teymur

    2011-01-01T23:59:59.000Z

    Solution-Processed Graphene Electronics,” Nano Letters, vol.applications,” Organic Electronics, vol. 12, no. 2, pp. 249-design in organic electronics by dual-gate technology,” in

  3. High conductivity electrolyte solutions and rechargeable cells incorporating such solutions

    DOE Patents [OSTI]

    Angell, C.A.; Zhang, S.S.; Xu, K.

    1998-10-20T23:59:59.000Z

    This invention relates generally to electrolyte solvents for use in liquid or rubbery polymer electrolyte solutions as are used, for example, in electrochemical devices. More specifically, this invention relates to sulfonyl/phospho-compound electrolyte solvents and sulfonyl/phospho-compound electrolyte solutions incorporating such solvents. 9 figs.

  4. Thorium Abundances in Solar Twins and Analogues: Implications for the Habitability of Extrasolar Planetary Systems

    E-Print Network [OSTI]

    Unterborn, Cayman T; Panero, Wendy R

    2015-01-01T23:59:59.000Z

    We present the first investigation of Th abundances in Solar twins and analogues to understand the possible range of this radioactive element and its effect on rocky planet interior dynamics and potential habitability. The abundances of the radioactive elements Th and U are key components of a planet's energy budget, making up 30% to 50% of the Earth's (Korenaga 2008; All\\`egre et al. 2001; Schubert et al. 1980; Lyubetskaya & Korenaga 2007; The KamLAND Collaboration 2011; Huang et al. 2013). Radiogenic heat drives interior mantle convection and surface plate tectonics, which sustains a deep carbon and water cycle and thereby aides in creating Earth's habitable surface. Unlike other heat sources that are dependent on the planet's specific formation history, the radiogenic heat budget is directly related to the mantle concentration of these nuclides. As a refractory element, the stellar abundance of Th is faithfully reflected in the terrestrial planet's concentration. We find that log eps Th varies from 59%...

  5. Lithium abundances in globular cluster giants: NGC 1904, NGC 2808, and NGC 362

    E-Print Network [OSTI]

    D'Orazi, V; Angelou, G C; Bragaglia, A; Carretta, E; Lattanzio, J C; Lucatello, S; Momany, Y; Sollima, A; Beccari, G

    2015-01-01T23:59:59.000Z

    The presence of multiple populations in globular clusters has been well established thanks to high-resolution spectroscopy. It is widely accepted that distinct populations are a consequence of different stellar generations: intra-cluster pollution episodes are required to produce the peculiar chemistry observed in almost all clusters. Unfortunately, the progenitors responsible have left an ambiguous signature and their nature remains unresolved. To constrain the candidate polluters, we have measured lithium and aluminium abundances in more than 180 giants across three systems: NGC~1904, NGC~2808, and NGC~362. The present investigation along with our previous analysis of M12 and M5 affords us the largest database of simultaneous determinations of Li and Al abundances. Our results indicate that Li production has occurred in each of the three clusters. In NGC~362 we detected an M12-like behaviour, with first and second-generation stars sharing very similar Li abundances favouring a progenitor that is able to pro...

  6. Oxygen in Galactic Disk Stars: non-LTE abundances from the 777 nm O I triplet

    E-Print Network [OSTI]

    I. Ramirez; C. Allende Prieto; D. L. Lambert

    2005-06-29T23:59:59.000Z

    Oxygen abundances for a large sample of dwarf and giant stars kinematically selected to be part of the Galactic thin and thick disks have been determined from a non-LTE analysis of the O I triplet lines at 777 nm. The abundance analysis was performed using the infrared flux method temperature scale, trigonometric surface gravities, and accurate atomic data. Within this framework, the ionization balance of iron lines could not be satisfied and so we adopted the iron abundances from Fe II lines only given that they are relatively less sensitive to changes in the atmospheric parameters. We show the resulting [O/Fe] vs. [Fe/H] relationship and briefly discuss its implications.

  7. Chemo-spectrophotometric evolution of spiral galaxies: III. Abundance and colour gradients in discs

    E-Print Network [OSTI]

    N. Prantzos; S. Boissier

    1999-11-07T23:59:59.000Z

    We study the relations between luminosity and chemical abundance profiles of spiral galaxies, using detailed models for the chemical and spectro-photometric evolution of galactic discs. The models are ``calibrated'' on the Milky Way disc and are successfully extended to other discs with the help of simple ``scaling'' relations, obtained in the framework of semi-analytic models of galaxy formation. We find that our models exhibit oxygen abundance gradients that increase in absolute value with decreasing disc luminosity (when expressed in dex/kpc) and are independent of disc luminosity (when expressed in dex/scalelength), both in agreement with observations. We notice an important strong correlation between abundance gradient and disc scalelength. These results support the idea of ``homologuous evolution'' of galactic discs.

  8. Low-power adaptive control scheme using switching activity measurement method for reconfigurable analog-to-digital converters 

    E-Print Network [OSTI]

    Ab Razak, Mohd Zulhakimi

    2014-06-30T23:59:59.000Z

    Power consumption is a critical issue for portable devices. The ever-increasing demand for multimode wireless applications and the growing concerns towards power-aware green technology make dynamically reconfigurable hardware an attractive solution...

  9. 2005 Nature Publishing Group Mammal-like muscles power swimming in a

    E-Print Network [OSTI]

    DeWitt, Thomas J.

    dorsal fin, where the RM is most abundant, showed that all sharks had a core temperature about 18­20 8C© 2005 Nature Publishing Group Mammal-like muscles power swimming in a cold-water shark Diego, within the fishes the tunas and lamnid sharks deviate from the ectothermic strategy, maintaining elevated

  10. ReseaRch DRiven FAU is utilizing the power of partnerships to go green,

    E-Print Network [OSTI]

    Fernandez, Eduardo

    as Florida Power & Light, the State of Florida Solar Energy System Incentives program and other state sources potential use as an abundant renewable energy source. The deployment of the ADCPs is the first step in COET's Center for Ocean Energy Technology (COET) deployed four acoustic doppler current profilers (ADCP

  11. Stellar abundances and molecular hydrogen in high-redshift galaxies -the far-ultraviolet view

    E-Print Network [OSTI]

    William C. Keel

    2006-02-27T23:59:59.000Z

    FUSE spectra of star-forming regions in nearby galaxies are compared to composite spectra of Lyman-break galaxies (LBGs), binned by strength of Lyman alpha emission and by mid-UV luminosity. Several far-UV spectral features, including lines dominated by stellar wind and by photospheric components, are very sensitive to stellar abundances. Their measurement in Lyman-break galaxies is compromised by the strong interstellar absorption features, allowing in some cases only upper limits. The derived C and N abundances in the LBGs are no higher than half solar (scaled to oxygen abundance for comparison with emission-line analyses), independent of the strength of Lyman alpha emission. P V absorption indicates abundances as low as 0.1 solar, with an upper limit near 0.4 solar in the reddest and weakest-emission galaxies. Unresolved interstellar absorption components would further lower the derived abundances. Trends of line strength, and derived abundances, are stronger with mid-UV luminosity than with Lyman-alpha strength. H2 absorption in the Lyman and Werner bands is very weak in the LBGs. Template H2 absorption spectra convolved to appropriate resolution show that strict upper limits N(H2)< 10^18 cm^-2 apply in all cases, with more stringent values appropriate for the stronger-emission composites and for mixes of H2 level populations like those on Milky Way sight lines. Since the UV-bright regions are likely to be widespread in these galaxies, these results rule out massive diffuse reservoirs of H2, and suggest that the dust/gas ratio is already fairly large at z~3.

  12. Early solar mass loss, opacity uncertainties, and the solar abundance problem

    SciTech Connect (OSTI)

    Guzik, Joyce Ann [Los Alamos National Laboratory; Keady, John [Los Alamos National Laboratory; Kilcrease, David [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    Solar models calibrated with the new element abundance mixture of Asplund et al. published in 2005 no longer produce good agreement with the sound speed, convection zone depth, and convection zone helium abundance inferred from solar oscillation data. Attempts to modify the input physics of the standard model, for example, by including enhanced diffusion, increased opacities, accretion, convective overshoot, or gravity waves have not restored the good agreement attained with the prior abundances. Here we present new models including early mass loss via a stronger solar wind. Early mass loss has been investigated prior to the solar abundance problem to deplete lithium and resolve the 'faint early sun problem'. We find that mass loss modifies the core structure and deepens the convection zone, and so improves agreement with oscillation data using the new abundances: however the amount of mass loss must be small to avoid destroying all of the surface lithium, and agreement is not fully restored. We also considered the prospects for increasing solar interior opacities. In order to increase mixture opacities by the 30% required to mitigate the abundance problem, the opacities of individual elements (e.g., O, N, C, and Fe) must be revised by a factor of two to three for solar interior conditions: we are investigating the possibility of broader calculated line wings for bound-bound transitions at the relevant temperatures to enhance opacity. We find that including all of the elements in the AGS05 opacity mixture (through uranium at atomic number Z=92) instead of only the 17 elements in the OPAL opacity mixture increases opacities by a negligible 0.2%.

  13. ATMOSPHERIC COMPOSITION OF WEAK G BAND STARS: CNO AND Li ABUNDANCES

    SciTech Connect (OSTI)

    Adamczak, Jens; Lambert, David L., E-mail: adamczak@astro.as.utexas.edu [McDonald Observatory, University of Texas, Austin, TX 78712 (United States)

    2013-03-10T23:59:59.000Z

    We determined the chemical composition of a large sample of weak G band stars-a rare class of G and K giants of intermediate mass with unusual abundances of C, N, and Li. We have observed 24 weak G band stars with the 2.7 m Harlan J. Smith Telescope at the McDonald Observatory and derived spectroscopic abundances for C, N, O, and Li, as well as for selected elements from Na-Eu. The results show that the atmospheres of weak G band stars are highly contaminated with CN-cycle products. The C underabundance is about a factor of 20 larger than for normal giants and the {sup 12}C/{sup 13}C ratio approaches the CN-cycle equilibrium value. In addition to the striking CN-cycle signature the strong N overabundance may indicate the presence of partially ON-cycled material in the atmospheres of the weak G band stars. The exact mechanism responsible for the transport of the elements to the surface has yet to be identified but could be induced by rapid rotation of the main sequence progenitors of the stars. The unusually high Li abundances in some of the stars are an indicator for Li production by the Cameron-Fowler mechanism. A quantitative prediction of a weak G band star's Li abundance is complicated by the strong temperature sensitivity of the mechanism and its participants. In addition to the unusual abundances of CN-cycle elements and Li, we find an overabundance of Na that is in accordance with the NeNa chain running in parallel with the CN cycle. Apart from these peculiarities, the element abundances in a weak G band star's atmosphere are consistent with those of normal giants.

  14. Sneak peek at electrofuels: Geobacter team aims for bio-based solution to solar energy storage

    E-Print Network [OSTI]

    Lovley, Derek

    Sneak peek at electrofuels: Geobacter team aims for bio-based solution to solar energy storage a hybrid of solar and bio-power and also solve the most perplexing problem facing solar energy: energy compounds, and oxygen is released as a byproduct," Lovley explains. Solar energy powers the microbes

  15. On the Exact Solution to a Smart Grid Cyber-Security Analysis Problem

    E-Print Network [OSTI]

    Johansson, Karl Henrik

    terminal units (RTUs), SCADA systems measure data such as trans- mission line power flows, bus power1 On the Exact Solution to a Smart Grid Cyber-Security Analysis Problem Kin Cheong Sou, Henrik Sandberg and Karl Henrik Johansson Abstract--This paper considers a smart grid cyber-security problem

  16. Presentation: Better Buildings Residential Program Solution Center...

    Office of Environmental Management (EM)

    Presentation: Better Buildings Residential Program Solution Center Presentation: Better Buildings Residential Program Solution Center Presentation: Better Buildings Residential...

  17. Conference Agenda: Residential Energy Efficiency Solutions 2012...

    Energy Savers [EERE]

    Conference Agenda: Residential Energy Efficiency Solutions 2012 Conference Agenda: Residential Energy Efficiency Solutions 2012 Presents conference agenda including a general...

  18. Novel Nanostructured Interface Solution for Automotive Thermoelectric...

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

    Nanostructured Interface Solution for Automotive Thermoelectric Modules Application Novel Nanostructured Interface Solution for Automotive Thermoelectric Modules Application...

  19. Seasonal abundance and diversity of ichthyoneuston in the northwestern Gulf of Mexico

    E-Print Network [OSTI]

    Daher, Mary Ann

    1979-01-01T23:59:59.000Z

    SEASONAL ABUNDANCE AND DIVERSITY OF ICHTHYONEUSTON IN THE NORTHWESTERN GULF OF MEXICO A Thesis by MARY ANN DAHER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... Committee: Dr. John D. McEachran Larvae of forty-six species of fishes were collected from neuston samples in the northwestern Gulf of Mexico during 1976 and January 1977. 1'h h d p ' * M~l~ht, H~l E . ~N' ' dl dB Ichthyoneuston was more abundant...

  20. Water Power for a Clean Energy Future (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-03-01T23:59:59.000Z

    This fact sheet provides an overview of the U.S. Department of Energy's Wind and Water Power Program's water power research activities. Water power is the nation's largest source of clean, domestic, renewable energy. Harnessing energy from rivers, manmade waterways, and oceans to generate electricity for the nation's homes and businesses can help secure America's energy future. Water power technologies fall into two broad categories: conventional hydropower and marine and hydrokinetic technologies. Conventional hydropower facilities include run-of-the-river, storage, and pumped storage. Most conventional hydropower plants use a diversion structure, such as a dam, to capture water's potential energy via a turbine for electricity generation. Marine and hydrokinetic technologies obtain energy from waves, tides, ocean currents, free-flowing rivers, streams and ocean thermal gradients to generate electricity. The United States has abundant water power resources, enough to meet a large portion of the nation's electricity demand. Conventional hydropower generated 257 million megawatt-hours (MWh) of electricity in 2010 and provides 6-7% of all electricity in the United States. According to preliminary estimates from the Electric Power Resource Institute (EPRI), the United States has additional water power resource potential of more than 85,000 megawatts (MW). This resource potential includes making efficiency upgrades to existing hydroelectric facilities, developing new low-impact facilities, and using abundant marine and hydrokinetic energy resources. EPRI research suggests that ocean wave and in-stream tidal energy production potential is equal to about 10% of present U.S. electricity consumption (about 400 terrawatt-hours per year). The greatest of these resources is wave energy, with the most potential in Hawaii, Alaska, and the Pacific Northwest. The Department of Energy's (DOE's) Water Power Program works with industry, universities, other federal agencies, and DOE's national laboratories to promote the development and deployment of technologies capable of generating environmentally sustainable and cost-effective electricity from the nation's water resources.

  1. Power Series Introduction

    E-Print Network [OSTI]

    Vickers, James

    Power Series 16.4 Introduction In this section we consider power series. These are examples of infinite series where each term contains a variable, x, raised to a positive integer power. We use the ratio test to obtain the radius of convergence R, of the power series and state the important result

  2. Offshore Wind Power USA

    Broader source: Energy.gov [DOE]

    The Offshore Wind Power USA conference provides the latest offshore wind market updates and forecasts.

  3. Holographic Superconductors with Power-Maxwell field

    E-Print Network [OSTI]

    Jiliang Jing; Qiyuan Pan; Songbai Chen

    2011-11-17T23:59:59.000Z

    With the Sturm-Liouville analytical and numerical methods, we investigate the behaviors of the holographic superconductors by introducing a complex charged scalar field coupled with a Power-Maxwell field in the background of $d$-dimensional Schwarzschild AdS black hole. We note that the Power-Maxwell field takes the special asymptotical solution near boundary which is different from all known cases. We find that the larger power parameter $q$ for the Power-Maxwell field makes it harder for the scalar hair to be condensated. We also find that, for different $q$, the critical exponent of the system is still 1/2, which seems to be an universal property for various nonlinear electrodynamics if the scalar field takes the form of this paper.

  4. Inverse diffusion from knowledge of power densities

    E-Print Network [OSTI]

    Bal, Guillaume; Monard, Francois; Triki, Faouzi

    2011-01-01T23:59:59.000Z

    This paper concerns the reconstruction of a diffusion coefficient in an elliptic equation from knowledge of several power densities. The power density is the product of the diffusion coefficient with the square of the modulus of the gradient of the elliptic solution. The derivation of such internal functionals comes from perturbing the medium of interest by acoustic (plane) waves, which results in small changes in the diffusion coefficient. After appropriate asymptotic expansions and (Fourier) transformation, this allow us to construct the power density of the equation point-wise inside the domain. Such a setting finds applications in ultrasound modulated electrical impedance tomography and ultrasound modulated optical tomography. We show that the diffusion coefficient can be uniquely and stably reconstructed from knowledge of a sufficient large number of power densities. Explicit expressions for the reconstruction of the diffusion coefficient are also provided. Such results hold for a large class of boundary...

  5. Dispersed power and renewables

    SciTech Connect (OSTI)

    O`Sullivan, J.B.

    1995-12-31T23:59:59.000Z

    Distributed power generation and renewable energy sources are discussed: The following topics are discussed: distributed resources, distributed generation, commercialization requirements, biomass power, location of existing biomass feedstocks, biomass business plan components, North Carolina BGCC partnership, New York biomass co-firing project, alfalfa for power and feed, Hawaii Pioneer Mill LOI project, next steps for biomass, wind power activity, photovoltaic modules and arrays, lead-acid batteries, superconducting magnetic energy storage, fuel cells, and electric power industry trends.

  6. Oxygen, {\\alpha}-element and iron abundance distributions in the inner part of the Galactic thin disc

    E-Print Network [OSTI]

    Martin, R P; Kovtyukh, V V; Korotin, S A; Yegorova, I A; Saviane, Ivo

    2015-01-01T23:59:59.000Z

    We derived elemental abundances in 27 Cepheids, the great majority situated within a zone of Galactocentric distances ranging from 5 to 7 kpc. One star of our sample, SU Sct, has a Galactocentric distance of about 3 kpc, and thus falls in a poorly investigated region of the inner thin disc. Our new results, combined with data on abundances in the very central part of our Galaxy taken from literature, show that iron, magnesium, silicon, sulfur, calcium and titanium LTE abundance radial distributions, as well as NLTE distribution of oxygen reveal a plateau-like structure or even positive abundance gradient in the region extending from the Galactic center to about 5 kpc.

  7. Is Nuclear Energy the Solution?

    E-Print Network [OSTI]

    Saier, Milton H.; Trevors, Jack T.

    2010-01-01T23:59:59.000Z

    fired power plant per unit of electrical energy. Wind powerpower plants will not be cost competitive with other electricity-generating alternatives. For example, wind

  8. Neutrino Physics Neutrinos rarely interact despite their vast abundance in nature. To give a sense of

    E-Print Network [OSTI]

    Chapter 1 Neutrino Physics Neutrinos rarely interact despite their vast abundance in nature later in 1933, Enrico Fermi devised a theory for beta decays which 1 #12;Chapter 1: Neutrino Physics 2 indicated oscillations [6]. This chapter will describe neutrino physics and some of the experiments

  9. Intervention Analysis of Hurricane Effects on Snail Abundance in a Tropical Forest Using

    E-Print Network [OSTI]

    Willig, Michael

    Intervention Analysis of Hurricane Effects on Snail Abundance in a Tropical Forest Using Long disturbances, such as hurricanes, have profound effects on pop- ulations, either directly by causing mortality of resources. In the last 20 years, two major disturbances, Hurricane Hugo in 1989 and Hurricane Georges

  10. Solar Cells from Earth-Abundant Semiconductors with Plasmon-Enhanced Light Absorption

    SciTech Connect (OSTI)

    Atwater, Harry

    2012-04-30T23:59:59.000Z

    Progress is reported in these areas: Plasmonic Light Trapping in Thin Film a-Si Solar Cells; Plasmonic Light Trapping in Thin InGaN Quantum Well Solar Cells; and Earth Abundant Cu{sub 2}O and Zn{sub 3}P{sub 2} Solar Cells.

  11. Rapid Communication Herpes simplex virus 1 microRNAs expressed abundantly during latent infection are

    E-Print Network [OSTI]

    Knipe, David M.

    Rapid Communication Herpes simplex virus 1 microRNAs expressed abundantly during latent infection Available online 23 July 2011 Keywords: Herpes simplex virus MicroRNAs Latency Gene regulation Several herpes simplex virus 1 microRNAs are encoded within or near the latency associated transcript (LAT) locus

  12. Sulfur, Chlorine, and Argon Abundances in Planetary Nebulae. III: Observations and Results for a Final Sample

    E-Print Network [OSTI]

    K. B. Kwitter; R. B. C. Henry; J. B. Milingo

    2002-09-25T23:59:59.000Z

    This paper is the fourth in a series whose purpose is to study the interstellar abundances of sulfur, chlorine, and argon in the Galaxy using a sample of 86 planetary nebulae. Here we present new high-quality spectrophotometric observations of 20 Galactic planetary nebulae with spectral coverage from 3700-9600 Angstroms. A major feature of our observations throughout the entire study has been the inclusion of the near-infrared lines of [S III] 9069,9532, which allows us to calculate accurate S+2 abundances and to either improve upon or convincingly confirm results of earlier sulfur abundance studies. For each of the 20 objects here we calculate ratios of S/O, Cl/O, and Ar/O and find average values of S/O=1.1E-2+/-1.1E-2, Cl/O=4.2E-4+/-5.3E-4, and Ar/O=5.7E-3+/-4.3E-3. For six objects we are able to compare abundances of S+3 calculated directly from available [S IV] 10.5 micron measurements with those inferred indirectly from the values of the ionization correction factors for sulfur. In the final paper of the series, we will compile results from all 86 objects, search for and evaluate trends, and use chemical evolution models to interpret our results.

  13. Seeding the Pregenetic Earth: Meteoritic Abundances of Nucleobases and Potential Reaction Pathways

    E-Print Network [OSTI]

    Pearce, Ben K D

    2015-01-01T23:59:59.000Z

    Carbonaceous chondrites are a class of meteorite known for having a high content of water and organics. In this study, abundances of the nucleobases, i.e., the building blocks of RNA and DNA, found in carbonaceous chondrites are collated from a variety of published data and compared across various meteorite classes. An extensive review of abiotic chemical reactions producing nucleobases is then performed. These reactions are then reduced to a list of 15 individual reaction pathways that could potentially occur within meteorite parent bodies. The nucleobases guanine, adenine and uracil are found in carbonaceous chondrites in the amounts of 1$-$500 ppb. It is currently unknown which reaction is responsible for their synthesis within the meteorite parent bodies. One class of carbonaceous meteorites dominate the abundances of both amino acids and nucleobases$-$the so-called CM2 (e.g. Murchison meteorite). CR2 meteorites (e.g. Graves Nunataks) also dominate the abundances of amino acids, but are the least abundant...

  14. Bringing you a prosperous future where energy is clean, abundant, reliable and affordable Industrial Technologies Program

    E-Print Network [OSTI]

    Beckermann, Christoph

    Industrial Technologies Program U.S. Department of Energy Office of Energy Efficiency and Renewable Energy of Energy Efficiency and Renewable Energy invests in a diverse portfolio of energy technologies. For moreBringing you a prosperous future where energy is clean, abundant, reliable and affordable

  15. The Effects of Disturbance Events on Abundance and Sex Ratios of a Terrestrial Turtle, Terrapene bauri

    E-Print Network [OSTI]

    Oli, Madan K.

    without catastrophic mortality, survivorship could be reduced following a disturbance, thus leading long-term effect on abundance as long as initial mortality is not severe and food resources remain. 2003). Both large (e.g., hurricanes) and small (e.g., wind damage in forested habitats) scale

  16. FOREST STRUCTURE AND PREY ABUNDANCE IN WINTER HABITAT OF NORTHERN GOSHAWKS

    E-Print Network [OSTI]

    Beier, Paul

    suited to goshawk maneu- verability and hunting behavior) is more important than prey abundance. During their breeding-season home ranges in ponderosa pine forest during winter. Meanwhile, most males moved into lower squirrel [Sciurus aberti]). Goshawks minimized energy expense and thermal exposure of flight by caching

  17. Monitoring Butterfly Abundance: Beyond Pollard Walks Jero^ me Pellet1,2

    E-Print Network [OSTI]

    Richner, Heinz

    Monitoring Butterfly Abundance: Beyond Pollard Walks Je´ro^ me Pellet1,2 *, Jason T. Bried3 , David to the characteristics of the species under scrutiny and resources availability. Citation: Pellet J, Bried JT, Parietti D Copyright: � 2012 Pellet et al. This is an open-access article distributed under the terms of the Creative

  18. Abundance, Composition, and Sinking Rates of Fish Fecal Pellets in the Santa

    E-Print Network [OSTI]

    Abundance, Composition, and Sinking Rates of Fish Fecal Pellets in the Santa Barbara Channel Grace.O. Box 1346, Gloucester Point, Virginia 23062, USA. Rapidly sinking fecal pellets are an important composition, particulate organic carbon/nitrogen (POC/PON), and sinking rates of fecal pellets produced

  19. EARTH ABUNDANT MATERIALS FOR HIGH EFFICIENCY HETEROJUNCTION THIN FILM SOLAR CELLS

    E-Print Network [OSTI]

    Ceder, Gerbrand

    materials for thin film solar cells such as CdTe and CIGS suffer from concerns over resource scarcity (eEARTH ABUNDANT MATERIALS FOR HIGH EFFICIENCY HETEROJUNCTION THIN FILM SOLAR CELLS Yun Seog Lee 1 conversion efficiencies should be increased. In terms of reducing module cost, thin film solar cells

  20. Abundant C4 plants on the Tibetan Plateau during the Lateglacial and early Holocene

    E-Print Network [OSTI]

    Covino, Tim

    Abundant C4 plants on the Tibetan Plateau during the Lateglacial and early Holocene Elizabeth K t Plants using the C4 (Hatch-Slack) photosynthetic pathway are key for global food production and account of modern naturally-occurring C4 plant species at elevations up to 4500 m in Tibet and 3000 m in Africa

  1. Plant Characteristics Associated with Natural Enemy Abundance at Michigan Native Plants

    E-Print Network [OSTI]

    Landis, Doug

    BEHAVIOR Plant Characteristics Associated with Natural Enemy Abundance at Michigan Native Plants A. K. FIEDLER1 AND D. A. LANDIS Department of Entomology, 204 Center for Integrated Plant Systems populations by providing them with plant resources such as pollen and nectar. Insects are known to respond

  2. Increased stray gas abundance in a subset of drinking water wells near Marcellus shale gas extraction

    E-Print Network [OSTI]

    Jackson, Robert B.

    Increased stray gas abundance in a subset of drinking water wells near Marcellus shale gas Pennsylvania, ex- amining natural gas concentrations and isotopic signatures with proximity to shale gas wells this transformation, with shale gas and other unconventional sources now yielding more than one- half of all US

  3. ON THE ABUNDANCE OF PRESOLAR SILICATE AND OXIDE GRAINS IN PRIMITIVE METEORITES.

    E-Print Network [OSTI]

    ON THE ABUNDANCE OF PRESOLAR SILICATE AND OXIDE GRAINS IN PRIMITIVE METEORITES. A. Nguyen1 , E of presolar silicates in IDPs and meteorites [1-3] has opened new opportunities. Isotopic analyses of elements for presolar silicates to the CO3.0 meteorite ALH77307. This search resulted in the discovery of 9 presolar

  4. Simulations of water isotope abundances in the upper troposphere and lower stratosphere and implications

    E-Print Network [OSTI]

    Gettelman, Andrew

    fractionation processes. The results indicate that water substance in the upper troposphere does not follow a Rayleigh distillation model due to the presence of condensed phase water. Stratospheric abundances and climate of the upper troposphere and lower stratosphere (UT/LS). It is broadly known that most of the air

  5. ABUNDANCE AND VERTICAL DISTRIBUTION OF FISHES IN A COBBLE-BOTTOM KELP FOREST OFF

    E-Print Network [OSTI]

    ABUNDANCE AND VERTICAL DISTRIBUTION OF FISHES IN A COBBLE-BOTTOM KELP FOREST OFF SAN ONOFRE composition,vertical distribution,and standingstockoffishes ina forest of giant kelp and a nearby kelp substrates, were rare or absent in these low-relief, cobble- bottom habitats. The species present in the kelp

  6. Nucleosynthesis and mixing on the Asymptotic Giant Branch. III. Predicted and observed s-process abundances

    E-Print Network [OSTI]

    M. Busso; R. Gallino; D. L. Lambert; C. Travaglio; V. V. Smith

    2001-04-26T23:59:59.000Z

    We present the results of s-process nucleosynthesis calculations for AGB stars of different metallicities and initial masses. The computations were based on previously published stellar evolutionary models that account for the III dredge up phenomenon occurring late on the AGB. Neutron production is driven by the 13C(alpha,n)16O reaction during the interpulse periods in a tiny layer in radiative equilibrium at the top of the He- and C-rich shell. The s-enriched material is subsequently mixed with the envelope by the III dredge up, and the envelope composition is computed after each thermal pulse. We follow the changes in the photospheric abundance of the Ba-peak elements (heavy s, or `hs') and that of the Zr-peak ones (light s, or `ls'), whose logarithmic ratio [hs/ls] has often been adopted as an indicator of the s-process efficiency. The theoretical predictions are compared with published abundances of s elements for Galactic AGB giants of classes MS, S, SC, post-AGB supergiants, and for various classes of binary stars. The observations in general confirm the complex dependence of n captures on metallicity. They suggest that a moderate spread exists in the abundance of 13C that is burnt in different stars. Although additional observations are needed, a good understanding has been achieved of s-process operation in AGB. The detailed abundance distribution including the light elements (CNO) of a few s-enriched stars at different metallicity are examined.

  7. Complex hydraulic and substrate variables limit freshwater mussel species richness and abundance

    E-Print Network [OSTI]

    Vaughn, Caryn

    Complex hydraulic and substrate variables limit freshwater mussel species richness and abundance. We examined how substrate and complex hydraulic variables limit the distribution of freshwater mussels. We sampled mussels and measured substrate and hydraulic variables (at low and high flows) at 6

  8. Abundance of narwhals (Monodon monoceros) on the hunting grounds in Greenland

    E-Print Network [OSTI]

    Laidre, Kristin L.

    Abundance of narwhals (Monodon monoceros) on the hunting grounds in Greenland M. P. HEIDE Greenland Institute of Natural Resources, Bok 570, 3900 Nuuk, Greenland (MPH, KLL, RGH) RUWPA, University to subsistence hunting by Inuit in Greenland and Canada. Scientific advice on the sustainable levels of removals

  9. NREL Explores Earth-Abundant Materials for Future Solar Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-10-01T23:59:59.000Z

    Researchers at the National Renewable Energy Laboratory (NREL) are using a theory-driven technique - sequential cation mutation - to understand the nature and limitations of promising solar cell materials that can replace today's technologies. Finding new materials that use Earth-abundant elements and are easily manufactured is important for large-scale solar electricity deployment.

  10. Bacterial traits, organism mass, and numerical abundance in the detrital soil food web of Dutch

    E-Print Network [OSTI]

    Cohen, Joel E.

    M and numerical abundance N. The microbial biomass and biodiversity of belowground fauna were and fragmentation. The quantity and diversity of litter are traditionally considered the bottom-up controlling donor). As the microbial biomass comprises the majority of the total biomass in soil, the role of top-down regulation

  11. Oxygen Abundances in the Milky Way Using X-ray Absorption Measurements Towards Galaxy Clusters

    E-Print Network [OSTI]

    Wayne H. Baumgartner; Richard F. Mushotzky

    2005-09-21T23:59:59.000Z

    We present measurements of the oxygen abundance of the Milky Way's ISM by observing the K-shell X-ray photoionization edge towards galaxy clusters. This effect is most easily observed towards objects with galactic columns (n_H) of a few times 1e21 cm^-2. We measure X-ray column densities towards 11 clusters and find that at high galactic columns above approximately 1e21 cm^-2 the X-ray columns are generally 1.5--3.0 times greater than the 21 cm H II columns, indicating that molecular clouds become an important contributor to n_H at higher columns. We find the average ISM oxygen abundance to be (O/H) = (4.85 +/- 0.06) x 10^-4, or 0.99 solar when using the most recent solar photospheric values. Since X-ray observations are sensitive to the total amount of oxygen present (gas + dust), these results indicate a high gas to dust ratio. Also, the oxygen abundances along lines of sight through high galactic columns (n_H) are the same as abundances through low columns, suggesting that the composition of denser clouds is similar to that of the more diffuse ISM.

  12. Using benthic infauna abundance and genetic markers in oysters as indicators of hypoxia downstream from a

    E-Print Network [OSTI]

    Vallino, Joseph J.

    Using benthic infauna abundance and genetic markers in oysters as indicators of hypoxia downstream on communities downstream from these systems has not been well assessed. This study sought to examine differences between regions downstream from a permeable reactive barrier and a control site at Waquoit Bay in three

  13. Deep-Sea Research II 52 (2005) 799822 Top predator distribution and abundance across the

    E-Print Network [OSTI]

    in abundance in the oceanic zone in 1998, 2001, and 2002, owing primarily to influxes of dark shearwaters 0967-0645/$ - see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.dsr2 and location of water masses strong

  14. NREL Highlights SCIENCE Use of Earth-abundant materials in solar absorber films

    E-Print Network [OSTI]

    NREL Highlights SCIENCE Use of Earth-abundant materials in solar absorber films is critical was proposed more than 25 years ago in the form of FeS2 pyrite--fool's gold. Unfortunately, the material has that can be used to identify new Fe-containing materials that can circumvent the limitations of FeS2 pyrite

  15. Abundance and species composition of amphibians, small mammals, and songbirds in

    E-Print Network [OSTI]

    Macdonald, Ellen

    buffer strips are left along water bodies after forest harvesting to protect water quality and fish report on changes in terrestrial vertebrate communities from pre- to post-harvest in experimentally levels, 3 replicates) before and after harvesting. Changes in small mammal or amphibian abundance were

  16. C/O abundance ratios, iron depletions, and infrared dust features in Galactic planetary nebulae

    E-Print Network [OSTI]

    Delgado-Inglada, Gloria

    2014-01-01T23:59:59.000Z

    We study the dust present in 56 Galactic planetary nebulae (PNe) through their iron depletion factors, their C/O abundance ratios (in 51 objects), and the dust features that appear in their infrared spectra (for 33 objects). Our sample objects have deep optical spectra of good quality, and most of them also have ultraviolet observations. We use these observations to derive the iron abundances and the C/O abundance ratios in a homogeneous way for all the objects. We compile detections of infrared dust features from the literature and we analyze the available Spitzer/IRS spectra. Most of the PNe have C/O ratios below one and show crystalline silicates in their infrared spectra. The PNe with silicates have C/O < 1, with the exception of Cn 1-5. Most of the PNe with dust features related to C-rich environments (SiC or the 30 {\\mu}m feature usually associated to MgS) have C/O $\\gtrsim$ 0.8. PAHs are detected over the full range of C/O values, including 6 objects that also show silicates. Iron abundances are low...

  17. Spatial pattern and temporal dynamics of northern bobwhite abundance and agricultural landuse, and potential casual factors

    E-Print Network [OSTI]

    Okay, Atiye Zeynep

    2006-04-12T23:59:59.000Z

    further intensified during World War II and the years following the war. These land use changes had overall negative effects on NBW habitat. Analysis of the changes in spatial pattern of NBW abundance in the Great Plains region during the severe drought...

  18. RESIK Solar X-ray flare element abundances on a non-isothermal assumption

    E-Print Network [OSTI]

    Sylwester, B; Sylwester, J; Kepa, A

    2015-01-01T23:59:59.000Z

    Solar X-ray spectra from the RESIK crystal spectrometer on the {\\em CORONAS-F} spacecraft (spectral range $3.3-6.1$~\\AA) are analyzed for thirty-three flares using a method to derive abundances of Si, S, Ar, and K, emission lines of which feature prominently in the spectra. For each spectrum, the method first optimizes element abundances then derives the differential emission measure as a function of temperature based on a procedure given by Sylwester et al. and Withbroe. This contrasts with our previous analyses of RESIK spectra in which an isothermal assumption was used. The revised abundances (on a logarithmic scale with $A({\\rm H}) = 12$) averaged for all the flares in the analysis are $A({\\rm Si}) = 7.53 \\pm 0.08$ (previously $7.89 \\pm 0.13$), $A({\\rm S}) = 6.91 \\pm 0.07$ ($7.16 \\pm 0.17$), $A({\\rm Ar}) = 6.47 \\pm 0.08$ ($6.45 \\pm 0.07$), and $A({\\rm K}) = 5.73 \\pm 0.19$ ($5.86 \\pm 0.20$), with little evidence for time variations of abundances within the evolution of each flare. Our previous estimates of...

  19. Parvalbumin 3 is an Abundant Ca2+ Buffer in Hair Cells

    E-Print Network [OSTI]

    Hudspeth, A. James

    Parvalbumin 3 is an Abundant Ca2+ Buffer in Hair Cells STEFAN HELLER,* ANDREA M. BELL, CHARLOTTE S parts of a hair cell. The Ca2+ concentration in ste- reocilia regulates adaptation and, through rapid saccular and chicken cochlear hair cells. We cloned cDNAs en- coding this protein from the corresponding

  20. The solar photospheric abundance of europium. Results from CO5BOLD 3-D hydrodynamical model atmospheres

    E-Print Network [OSTI]

    A. Mucciarelli; E. Caffau; B. Freytag; H. -G. Ludwig; P. Bonifacio

    2008-03-06T23:59:59.000Z

    Context. Europium is an almost pure r-process element, which may be useful as a reference in nucleocosmochronology. Aims. To determine the photospheric solar abundance using CO5BOLD 3-D hydrodynamical model atmospheres. Methods. Disc-centre and integrated-flux observed solar spectra are used. The europium abundance is derived from the equivalent width measurements. As a reference 1D model atmospheres have been used, in addition. Results. The europium photospheric solar abundance is 0.52 +- 0.02 in agreement with previous determinations. We also determine the photospheric isotopic fraction of Eu(151) to be 49 % +- 2.3 % from the intensity spectra and 50% +-2.3 from the flux spectra. This compares well to the the meteoritic isotopic fraction 47.8%. We explore the 3D corrections also for dwarfs and sub-giants in the temperature range ~5000 K to ~6500 K and solar and 1/10--solar metallicities and find them to be negligible for all the models investigated. Conclusions. Our photospheric Eu abundance is in good agreement with previous determinations based on 1D models. This is in line with our conclusion that 3D effects for this element are negligible in the case of the Sun.

  1. The solar photospheric abundance of europium. Results from CO5BOLD 3-D hydrodynamical model atmospheres

    E-Print Network [OSTI]

    Mucciarelli, A; Freytag, B; Ludwig, H -G; Bonifacio, P

    2008-01-01T23:59:59.000Z

    Context. Europium is an almost pure r-process element, which may be useful as a reference in nucleocosmochronology. Aims. To determine the photospheric solar abundance using CO5BOLD 3-D hydrodynamical model atmospheres. Methods. Disc-centre and integrated-flux observed solar spectra are used. The europium abundance is derived from the equivalent width measurements. As a reference 1D model atmospheres have been used, in addition. Results. The europium photospheric solar abundance is 0.52 +- 0.02 in agreement with previous determinations. We also determine the photospheric isotopic fraction of Eu(151) to be 49 % +- 2.3 % from the intensity spectra and 50% +-2.3 from the flux spectra. This compares well to the the meteoritic isotopic fraction 47.8%. We explore the 3D corrections also for dwarfs and sub-giants in the temperature range ~5000 K to ~6500 K and solar and 1/10--solar metallicities and find them to be negligible for all the models investigated. Conclusions. Our photospheric Eu abundance is in good agre...

  2. Abundance gradients in the Milky Way for alpha elements, Iron peak elements, Barium, Lanthanum and Europium

    E-Print Network [OSTI]

    G. Cescutti; F. Matteucci; P. Francois; C. Chiappini

    2006-09-29T23:59:59.000Z

    We model the abundance gradients in the disk of the Milky Way for several chemical elements (O, Mg, Si, S, Ca, Sc, Ti, Co, V, Fe, Ni, Zn, Cu, Mn, Cr, Ba, La and Eu), and compare our results with the most recent and homogeneous observational data. We adopt a chemical evolution model able to well reproduce the main properties of the solar vicinity. We compute, for the first time, the abundance gradients for all the above mentioned elements in the galactocentric distance range 4 - 22 kpc. The comparison with the observed data on Cepheids in the galactocentric distance range 5-17 kpc gives a very good agreement for many of the studied elements. In addition, we fit very well the data for the evolution of Lanthanum in the solar vicinity for which we present results here for the first time. We explore, also for the first time, the behaviour of the abundance gradients at large galactocentric distances by comparing our results with data relative to distant open clusters and red giants and select the best chemical evolution model model on the basis of that. We find a very good fit to the observed abundance gradients, as traced by Cepheids, for most of the elements, thus confirming the validity of the inside-out scenario for the formation of the Milky Way disk as well as the adopted nucleosynthesis prescriptions.

  3. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    E-Print Network [OSTI]

    Chen, Zhe

    as the studied power system. Simulation results show that the proposed control strategies are effective means into the modern power systems. In Denmark, the wind energy supplies around 20% of the annual electricity demand system frequency control solutions, such as frequency control from wind power plants may be needed

  4. A Novel Power Flow Method for Long Term Frequency Stability Analysis

    E-Print Network [OSTI]

    Yan, Wenjin

    2013-05-06T23:59:59.000Z

    This thesis presents a novel approach for a power system to find a practical power flow solution when all the generators in the system have hit their real power output limits, such as some generator units shutting down or load outages. The approach...

  5. Idetic: A High-level Synthesis Approach for Enabling Long Computations on Transiently-powered ASICs

    E-Print Network [OSTI]

    Circuits (ASICs) with energy harvesting sources. We address the power transiency and unpredictability prob RF power through an RFID-reader and stores the energy in a 3.3µF capacitor. For storage devices make them an attractive solution for ultra-low power applications. Despite the fact that energy

  6. Master Thesis KTH/ ICT / ECS -2007 -123 System-level power management design

    E-Print Network [OSTI]

    Jantsch, Axel

    i Master Thesis KTH/ ICT / ECS - 2007 - 123 System-level power management design on portable management (DPM) schemes (also called policies) can be used to control the power consumption levels consumption of a Philips multimedia device prototype, and introduced a dynamic power management solution

  7. Dynamic power management (DPM) is important for multicore architectures. One important challenge for

    E-Print Network [OSTI]

    Sorin, Daniel J.

    1 Abstract Dynamic power management (DPM) is important for multicore architectures. One important). The verification diffi- culty varies among designs, depending, for example, on the particular power management systems motivate the development and evaluation of efficient power manage- ment solutions targeted

  8. Security Constrained Optimal Power Flow 1.0 Introduction and notation

    E-Print Network [OSTI]

    McCalley, James D.

    1 Security Constrained Optimal Power Flow 1.0 Introduction and notation Figure 1 below compares the optimal power flow (OPF) with the security-constrained optimal power flow (SCOPF). Fig. 1 Some comments normal flow moves from just 100% of continuous rating. SCOPF differs from an OPF solution

  9. Power-Aware DBMS: Potential and Challenges Yi-cheng Tu1

    E-Print Network [OSTI]

    Tu, Yicheng

    Power-Aware DBMS: Potential and Challenges Yi-cheng Tu1 , Xiaorui Wang2 , and Zichen Xu1 1-aware DBMS and sketch our solutions to such issues. Specifically, we believe that the ability for the DBMS. Keywords: Power-aware DBMS, feedback control, energy profile iden- tification, system modeling, power cost

  10. Active Power Control from Wind Power (Presentation)

    SciTech Connect (OSTI)

    Ela, E.; Brooks, D.

    2011-04-01T23:59:59.000Z

    In order to keep the electricity grid stable and the lights on, the power system relies on certain responses from its generating fleet. This presentation evaluates the potential for wind turbines and wind power plants to provide these services and assist the grid during critical times.

  11. High power fast ramping power supplies

    SciTech Connect (OSTI)

    Marneris,I.; Bajon, E.; Bonati, R.; Sandberg, J.; Roser, T.; Tsoupas, N.

    2009-05-04T23:59:59.000Z

    Hundred megawatt level fast ramping power converters to drive proton and heavy ion machines are under research and development at accelerator facilities in the world. This is a leading edge technology. There are several topologies to achieve this power level. Their advantages and related issues will be discussed.

  12. Macroinvertebrate Abundance and Biomass: 2007 Data, BPA-51; Preliminary Report, February 10, 2009..

    SciTech Connect (OSTI)

    Holderman, Charles

    2009-02-10T23:59:59.000Z

    Four Excel files containing information on the 2007 macroinvertebrate data were initially provided to Statistical Consulting Services (SCS) by EcoAnalysts on 1/27/2009. These data files contained information on abundance and biomass data at the level of taxonomic groups. The data were subsequently reformatted and compiled, and aggregated for analysis by SCS. All descriptions and analyses below relate to this compiled data. Computations were carried out separately for each site over all sample periods. Basic summary information for both the abundance and biomass data is presented in Print Out No.2. The 14 sites varied widely in their minimum, mean, maximum and variance values. The number of observations ranged from 10 to 18. Some large abundance values (abundance > 40,000) were noted for sites KR6 and KR13. A more detailed summary of each site is given in Print Out No.3. Site KR3, for example, had a mean abundance of 6914 with a sample size of 17. The variance was 4591991 and the standard error of the mean was 1643. The skewness value, a measure of symmetry for the frequency distribution, was moderately large at 1.29 indicating an asymmetric distribution. Biomass for KR3 had a mean value of 0.87 g/m{sup 2} with 17 observations. The variance was 0.8872 and the standard error was 0.228 g/m{sup 2}. Skewness for biomass was also high at 1.29. Further examination of the quantiles and frequency plots for abundance and biomass also indicate considerable skewness. The stem and leaf diagram (frequency plot) for abundance in KR3 shows most of the data centered on smaller values with a few very large counts. The distribution for biomass has a similar pattern. Statistical tests for normality are significant for both response variables in KR3, thus, the hypothesis that the data originates from a symmetric normal distribution is rejected. Because sample size estimation and statistical inference assume normally distributed data, a transformation of the data is required prior to further analysis. As was the case for previous years, the natural logarithm was chosen as a transformation to mitigate distributional skewness. Abundance and biomass for the remaining sites were also notably skewed, therefore, these data were also log transformed prior to analysis. Summary information for the transformed data (referred to as L-abun and L-bio for abundance and biomass, respectively) are given in Print Out No.4. For site KR3, the logarithmic transformation reduced skewness value for biomass to -0.66. The distributions of abundance and biomass in the other sites also generally showed improvement as well. Hence, all subsequent statistical analyses reported here will be based on the log transformed data.

  13. Fourier expansions for a logarithmic fundamental solution of the polyharmonic equation

    E-Print Network [OSTI]

    Howard S. Cohl

    2012-02-08T23:59:59.000Z

    In even-dimensional Euclidean space for integer powers of the Laplacian greater than or equal to the dimension divided by two, a fundamental solution for the polyharmonic equation has logarithmic behavior. We give two approaches for developing a Fourier expansion of this logarithmic fundamental solution. The first approach is algebraic and relies upon the construction of two-parameter polynomials. We describe some of the properties of these polynomials, and use them to derive the Fourier expansion for a logarithmic fundamental solution of the polyharmonic equation. The second approach depends on the computation of parameter derivatives of Fourier series for a power-law fundamental solution of the polyharmonic equation. The resulting Fourier series is given in terms of sums over associated Legendre functions of the first kind. We conclude by comparing the two approaches and giving the azimuthal Fourier series for a logarithmic fundamental solution of the polyharmonic equation in rotationally-invariant coordinate systems.

  14. Abundance profiling of extremely metal-poor stars and supernova properties in the early universe

    SciTech Connect (OSTI)

    Tominaga, Nozomu [Department of Physics, Faculty of Science and Engineering, Konan University, 8-9-1 Okamoto, Kobe, Hyogo 658-8501 (Japan); Iwamoto, Nobuyuki [Nuclear Data Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Nomoto, Ken'ichi, E-mail: tominaga@konan-u.ac.jp, E-mail: iwamoto.nobuyuki@jaea.go.jp, E-mail: nomoto@astron.s.u-tokyo.ac.jp [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)

    2014-04-20T23:59:59.000Z

    After the big bang nucleosynthesis, the first heavy element enrichment in the universe was made by a supernova (SN) explosion of a population (Pop) III star (Pop III SN). The abundance ratios of elements produced from Pop III SNe are recorded in abundance patterns of extremely metal-poor (EMP) stars. The observations of the increasing number of EMP stars have made it possible to statistically constrain the explosion properties of Pop III SNe. We present Pop III SN models whose nucleosynthesis yields well reproduce, individually, the abundance patterns of 48 such metal-poor stars as [Fe/H] ? – 3.5. We then derive relations between the abundance ratios of EMP stars and certain explosion properties of Pop III SNe: the higher [(C + N)/Fe] and [(C + N)/Mg] ratios correspond to the smaller ejected Fe mass and the larger compact remnant mass, respectively. Using these relations, the distributions of the abundance ratios of EMP stars are converted to those of the explosion properties of Pop III SNe. Such distributions are compared with those of the explosion properties of present day SNe: the distribution of the ejected Fe mass of Pop III SNe has the same peak as that of the present day SNe but shows an extended tail down to ?10{sup –2}-10{sup –5} M {sub ?}, and the distribution of the mass of the compact remnant of Pop III SNe is as wide as that of the present-day, stellar-mass black holes. Our results demonstrate the importance of large samples of EMP stars obtained by ongoing and future EMP star surveys and subsequent high-dispersion spectroscopic observations in clarifying the nature of Pop III SNe in the early universe.

  15. Fundamental Parameters and Abundances of Metal-Poor Stars: The SDSS Standard BD +17 4708

    E-Print Network [OSTI]

    I. Ramirez; C. Allende Prieto; S. Redfield; D. L. Lambert

    2006-08-25T23:59:59.000Z

    The atmospheric parameters and iron abundance of the Sloan Digital Sky Survey (SDSS) spectrophotometric standard star BD +17 4708 are critically examined using up-to-date Kurucz model atmospheres, LTE line formation calculations, and reliable atomic data. We find Teff = 6141+-50 K, log g = 3.87+-0.08, and [Fe/H]=-1.74+-0.09. The line-of-sight interstellar reddening, bolometric flux, limb-darkened angular diameter, stellar mass, and the abundances of Mg, Si, and Ca are also obtained. This star is a unique example of a moderately metal-poor star for which the effective temperature can be accurately constrained from the observed spectral energy distribution (corrected for reddening). Such analysis leads to a value that is higher than most spectroscopic results previously reported in the literature (~5950 K). We find that the ionization balance of Fe lines is satisfied only if a low Teff (~5950 K) is adopted. With our preferred Teff (6141 K), the mean iron abundance we obtain from the FeII lines is lower by about 0.15 dex than that from the FeI lines, and therefore, the discrepancy between the mean iron abundance from FeI and FeII lines cannot be explained by overionization by UV photons as the main non-LTE effect. We also comment on non-LTE effects and the importance of inelastic collisions with neutral H atoms in the determination of oxygen abundances in metal-poor stars from the 777 nm OI triplet. (Abridged)

  16. Measurement Practices for Reliability and Power Quality

    SciTech Connect (OSTI)

    Kueck, JD

    2005-05-06T23:59:59.000Z

    This report provides a distribution reliability measurement ''toolkit'' that is intended to be an asset to regulators, utilities and power users. The metrics and standards discussed range from simple reliability, to power quality, to the new blend of reliability and power quality analysis that is now developing. This report was sponsored by the Office of Electric Transmission and Distribution, U.S. Department of Energy (DOE). Inconsistencies presently exist in commonly agreed-upon practices for measuring the reliability of the distribution systems. However, efforts are being made by a number of organizations to develop solutions. In addition, there is growing interest in methods or standards for measuring power quality, and in defining power quality levels that are acceptable to various industries or user groups. The problems and solutions vary widely among geographic areas and among large investor-owned utilities, rural cooperatives, and municipal utilities; but there is still a great degree of commonality. Industry organizations such as the National Rural Electric Cooperative Association (NRECA), the Electric Power Research Institute (EPRI), the American Public Power Association (APPA), and the Institute of Electrical and Electronics Engineers (IEEE) have made tremendous strides in preparing self-assessment templates, optimization guides, diagnostic techniques, and better definitions of reliability and power quality measures. In addition, public utility commissions have developed codes and methods for assessing performance that consider local needs. There is considerable overlap among these various organizations, and we see real opportunity and value in sharing these methods, guides, and standards in this report. This report provides a ''toolkit'' containing synopses of noteworthy reliability measurement practices. The toolkit has been developed to address the interests of three groups: electric power users, utilities, and regulators. The report will also serve to support activities to develop and share information among industry and regulatory participants about critical resources and practices. The toolkit has been developed by investigating the status of indices and definitions, surveying utility organizations on information sharing, and preparing summaries of reliability standards and monitoring requirements--the issues, needs, work under way, existing standards, practices and guidelines--for the following three classifications: (1) terms and definitions of reliability; (2) power quality standards, guidelines, and measurements; and (3) activities and organizations developing and sharing information on distribution reliability. As these synopses of reliability measurement practices are provided, it must be noted that an economic penalty may be associated with requiring too high a reliability level from the distribution system for all customers. It may be appropriate for the distribution system to supply only some base, generally accepted level of reliability. This base level would be adequate for the majority of customers. Users who need a higher level may find it economical to supply using distributed energy resources (DER) and other local solutions to reliability and power quality needs. Local solutions implemented by the customer may be the most cost-effective method for addressing the more stringent needs of a digital economy. These local solutions include energy storage, small distributed generators, and microgrids. This report also considers the market's role in addressing reliability issues and requirements. The customer's needs are discussed in view of issues such as power quality requirements of digital electronic equipment, the cost of outages, the cost of storage and new infrastructure, and natural gas prices. The market role in addressing these issues and requirements is explored. The economic considerations associated with the reliability issues are discussed, as well as the levels at which these economic decisions could be made. Finally, a discussion is provided of the role DER could play in addressing

  17. Establishment of the International Power Institute. Final technical report

    SciTech Connect (OSTI)

    Julius E. Coles

    2000-08-04T23:59:59.000Z

    The International Power Institute, in collaboration with American industries, seeks to address technical, political, economic and cultural issues of developing countries in the interest of facilitating profitable transactions in power related infrastructure projects. IPI works with universities, governments and commercial organizations to render project-specific recommendations for private-sector investment considerations. IPI also established the following goals: Facilitate electric power infrastructure transactions between developing countries and the US power industry; Collaborate with developing countries to identify development strategies to achieve energy stability; and Encourage market driven solutions and work collaboratively with other international trade energy, technology and banking organizations.

  18. Power-law tailed spectra from equilibrium

    E-Print Network [OSTI]

    T. S. Biro; G. Purcsel; G. Gyorgyi; A. Jakovac; Zs. Schram

    2005-10-03T23:59:59.000Z

    We propose that power-law tailed hadron spectra may be viewed as stemming from a matter in an unconventional equilibrium state typical for non-extensive thermodynamics. A non-extensive Boltzmann equation, which is able to form such spectra as a stationary solution, is utilized as a rough model of quark matter hadronization. Basic ideas about non-extensive simulation of the QCD equation of state on the lattice are presented.

  19. Is Nuclear Energy the Solution?

    E-Print Network [OSTI]

    Saier, Milton H.; Trevors, Jack T.

    2010-01-01T23:59:59.000Z

    10.1007/s11270-009-0270-y Is Nuclear Energy the Solution?MHS) attended a lecture on “Nuclear Responsibility” on theof the Alliance for Nuclear Responsibility. The information

  20. SciTech Connect: A Solution for Solution-Produced [beta]-FeSe...

    Office of Scientific and Technical Information (OSTI)

    A Solution for Solution-Produced beta-FeSe: Elucidating and Overcoming Factors that Prevent Superconductivity Citation Details In-Document Search Title: A Solution for...

  1. UGP Power Projects

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

    wildlife and power generation on the Missouri River. Seven dams and powerplants have the installed capacity of 2,610 MW. That hydroelectric power is delivered across about 7,919...

  2. Residential Wind Power

    E-Print Network [OSTI]

    Willis, Gary

    2011-12-16T23:59:59.000Z

    This research study will explore the use of residential wind power and associated engineering and environmental issues. There is various wind power generating devices available to the consumer. The study will discuss the dependencies of human...

  3. Power production and ADS

    SciTech Connect (OSTI)

    Raja, Rajendran; /Fermilab

    2010-03-01T23:59:59.000Z

    We describe the power production process in Accelerator Driven Sub-critical systems employing Thorium-232 and Uranium-238 as fuel and examine the demands on the power of the accelerator required.

  4. Power Factor Improvement

    E-Print Network [OSTI]

    Viljoen, T. A.

    1979-01-01T23:59:59.000Z

    Power factor control is a necessary ingredient in any successful Energy Management Program. Many companies are operating with power factors of 70% or less and are being penalized through the electrical utility bill. This paper starts by describing...

  5. PowerPoint Presentation

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

    Research Center Blvd. Fayetteville, AR 72701 Phone: (479)-443-5759 Email: marcelo@apei.net Website: www.apei.net High Temperature and High Power Density SiC Power Electronic...

  6. Idaho Power- Net Metering

    Broader source: Energy.gov [DOE]

    Idaho does not have a statewide net-metering policy. However, each of the state's three investor-owned utilities -- Avista Utilities, Idaho Power and Rocky Mountain Power -- has developed a net...

  7. PowerPoint Presentation

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

    Research Center Blvd. Fayetteville, AR 72701 Phone: (479)-443-5759 Email: mschupb@apei.net Website: www.apei.net High Power Density Silicon Carbide Power Electronic Converters...

  8. Space Solar Power Program

    SciTech Connect (OSTI)

    Arif, H.; Barbosa, H.; Bardet, C.; Baroud, M.; Behar, A.; Berrier, K.; Berthe, P.; Bertrand, R.; Bibyk, I.; Bisson, J.; Bloch, L.; Bobadilla, G.; Bourque, D.; Bush, L.; Carandang, R.; Chiku, T.; Crosby, N.; De Seixas, M.; De Vries, J.; Doll, S.; Dufour, F.; Eckart, P.; Fahey, M.; Fenot, F.; Foeckersperger, S.; Fontaine, J.E.; Fowler, R.; Frey, H.; Fujio, H.; Gasa, J.M.; Gleave, J.; Godoe, J.; Green, I.; Haeberli, R.; Hanada, T.; Ha

    1992-08-01T23:59:59.000Z

    Information pertaining to the Space Solar Power Program is presented on energy analysis; markets; overall development plan; organizational plan; environmental and safety issues; power systems; space transportation; space manufacturing, construction, operations; design examples; and finance.

  9. Green Power Purchase Plan

    Broader source: Energy.gov [DOE]

    Class I renewable energy resources include solar, wind, new sustainable biomass, landfill gas, fuel cells (using renewable or non-renewable fuels), ocean thermal power, wave or tidal power, low...

  10. Body powered thermoelectric systems

    E-Print Network [OSTI]

    Settaluri, Krishna Tej

    2012-01-01T23:59:59.000Z

    Great interest exists for and progress has be made in the effective utilization of the human body as a possible power supply in hopes of powering such applications as sensors and continuously monitoring medical devices ...

  11. Soldier power. Battery charging.

    E-Print Network [OSTI]

    Hong, Deog Ki

    hours runtime at full load 50 W #12; (%) (kW) 300 1-5 Siemens-Power 30 (hr) 10,000 Siemens 300 Acumentrics 80 (mW/cm2) 600 400 Siemens-Power 85 (hr) 70,000 3,000 Siemens-Power 15 () 500 25 Siemens-Power 60 >2013 - , Bloom, MHI, Rolls Royce 6 #12; SOFCSOFC * (LSCF ) ( Ag

  12. Concentrating Solar Power

    SciTech Connect (OSTI)

    Not Available

    2008-09-01T23:59:59.000Z

    Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.

  13. Power Prepayment Program

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project OfficePower Electronics Power Electronics PowerPower

  14. Estimating and decomposing total uncertainty for survey-based abundance estimates of Norwegian spring-spawning herring

    E-Print Network [OSTI]

    Aldrin, Magne

    the Norwegian coast, feed in the Norwegian Sea and adjacent areas, and overwinter in various partsEstimating and decomposing total uncertainty for survey-based abundance estimates of Norwegian uncertainty for survey-based abundance estimates of Norwegian spring-spawning herring. ­ ICES Journal

  15. Time-dependent extinction rate and species abundance in a tangled-nature model of biological evolution

    E-Print Network [OSTI]

    Christensen, Kim

    Time-dependent extinction rate and species abundance in a tangled-nature model of biological properties. The macrodynamics exhibit intermittent two-mode switching with a gradually decreasing extinction sense. The form of the species abundance curve compares well with observed func- tional forms. The model

  16. SOLAR WIND HELIUM ABUNDANCE AS A FUNCTION OF SPEED AND HELIOGRAPHIC LATITUDE: VARIATION THROUGH A SOLAR CYCLE

    E-Print Network [OSTI]

    Richardson, John

    SOLAR WIND HELIUM ABUNDANCE AS A FUNCTION OF SPEED AND HELIOGRAPHIC LATITUDE: VARIATION THROUGH of the variation of the relative abundance of helium to hydrogen in the solar wind as a function of solar wind theoretical work in which enhancements of coronal helium lead to stagnation of the escaping proton flux

  17. OXYGEN ABUNDANCE OF OPEN CLUSTER DWARFS Department of Astronomy, Peking University, Beijing 100871, China; shenzx@bac.pku.edu.cn

    E-Print Network [OSTI]

    Liu, Xiaowei

    OXYGEN ABUNDANCE OF OPEN CLUSTER DWARFS Z.-X. Shen Department of Astronomy, Peking University 100871, China Received 2005 June 30; accepted 2007 January 19 ABSTRACT We present oxygen abundances in the open cluster Pleiades derived from the [O i] k6300 forbidden line. Stellar parameters and oxygen

  18. Chemical abundances in the extremely carbon-rich and xenon-rich halo planetary nebula H4-1

    SciTech Connect (OSTI)

    Otsuka, Masaaki [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Tajitsu, Akito, E-mail: otsuka@asiaa.sinica.edu.tw, E-mail: tajitsu@subaru.naoj.org [Subaru Telescope, NAOJ, 650 North A'ohoku Place, Hilo, HI 96720 (United States)

    2013-12-01T23:59:59.000Z

    We performed detailed chemical abundance analysis of the extremely metal-poor ([Ar/H] ? –2) halo planetary nebula (PN) H4-1 based on the multi-wavelength spectra from Subaru/HDS, GALEX, SDSS, and Spitzer/IRS and determined the abundances of 10 elements. The C and O abundances were derived from collisionally excited lines (CELs) and are almost consistent with abundances from recombination lines (RLs). We demonstrated that the large discrepancy in the C abundance between CEL and RL in H4-1 can be solved using the temperature fluctuation model. We reported the first detection of the [Xe III] ?5846 line in H4-1 and determination of its elemental abundance ([Xe/H] > +0.48). H4-1 is the most Xe-rich PN among the Xe-detected PNe. The observed abundances are close to the theoretical prediction by a 2.0 M {sub ?} single star model with an initially element rich ([r/Fe] = +2.0 dex) rapid neutron-capture process (r-process). The observed Xe abundance would be a product of the r-process in primordial supernovae. The [C/O]-[Ba/(Eu or Xe)] diagram suggests that the progenitor of H4-1 shares the evolution with carbon-enhanced metal-poor (CEMP)-r/s and CEMP-no stars. The progenitor of H4-1 is presumably a binary formed in an r-process-rich environment.

  19. THE ABUNDANCE OF CARBON DIOXIDE ICE IN THE QUIESCENT INTRACLOUD MEDIUM D. C. B. Whittet,1,2

    E-Print Network [OSTI]

    Gerakines, Perry

    THE ABUNDANCE OF CARBON DIOXIDE ICE IN THE QUIESCENT INTRACLOUD MEDIUM D. C. B. Whittet,1,2 S. S: ISM: lines and bands -- ISM: molecules 1. INTRODUCTION Carbon dioxide (CO2) has proven to be a common embedded sources. Key properties include abundance relative to other ice constituents and dust extinction

  20. Power/Privilege Definitions

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Major; People's Institute for Survival and Beyond, New Orleans 2. Power is the ability to define reality and to convince other people that it is their definition. ~ Dr. Wade Nobles 3. Power is the capacity to act. 4 different cultures. [JL] RACISM Racism is race prejudice plus power [See Racist]. People's Institute calls