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  1. Vacancy Announcement Status Report, Updated 01/09/03

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

    About Us » Careers » Vacancies Vacancies Vacancies Interested candidates can apply to the following Office of the Inspector General job opportunities at: http://www.usajobs.gov . USAJOBS is the Federal Government's official website for federal jobs and employment information. Click on the Announcement number to view the job on USAJOBS. Announcement No: OIG-16-RG-0065 Position: Information Technology Auditor, GS-0511-07/09 Duty Location: Oak Ridge, TN Area of Consideration: Recent Graduate

  2. Complete LNG Terminal Status Maps | Department of Energy

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

    Complete LNG Terminal Status Maps Complete LNG Terminal Status Maps A series of slides showing the status of various LNG terminals (existing, under construction, proposed, etc.) in...

  3. Complete LNG Terminal Status Maps | Department of Energy

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

    Complete LNG Terminal Status Maps Complete LNG Terminal Status Maps A series of slides showing the status of various LNG terminals (existing, under construction, proposed, etc.) in North America. Complete LNG Terminal Status Map as of December 2012 (997.96 KB) More Documents & Publications Summary of LNG Export Applications of the Lower 48 States EA-1942: Finding of No Significant Impact ORDER NO. 3413: Jordan Cove LNG

  4. Vacancies | Department of Energy

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

    About Us » Careers » Vacancies Vacancies Vacancies Interested candidates can apply to the following Office of the Inspector General job opportunities at: http://www.usajobs.gov . USAJOBS is the Federal Government's official website for federal jobs and employment information. Click on the Announcement number to view the job on USAJOBS. Announcement No: OIG-16-MP-0063 Position: Lead Inspector, GS-1801-14 Duty Location: Albuquerque, NM Area of Consideration: Status Candidates Open: 7/25/2016

  5. Vacancy announcements

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

    July 2015 » Vacancy announcements Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues » submit Vacancy announcements Join our team or tell a friend July 1, 2015 Vacancy announcements Vacancy announcements Contact Linda Anderman Email For the most up-to-date employment opportunities, go to our employment website. The jobs below were available as of the distribution date. Job title Organization Nanoscale Electronics &

  6. Vacancy announcements

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

    Vacancy announcements Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues » submit Vacancy announcements Join our team or tell a friend November 1, 2014 Vacancy announcements Vacancy announcements Contact Linda Anderman Email For the most up-to-date employment opportunities, go to our employment website. The jobs below were available as of the distribution date. Job title Organization Scientist 3 WX-6/Explosive Applications &

  7. Vacancy announcements

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

    Vacancy announcements Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues » submit Vacancy announcements Join our team or tell a friend March 1, 2015 Vacancy announcements Vacancy announcements Contact Linda Anderman Email For the most up-to-date employment opportunities, go to our employment website. The jobs below were available as of the distribution date. Job title Organization Deputy Group Leader (R&D Manager 3)

  8. Vacancy announcements

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

    Intelligence and Counterintelligence Search Search form Search Office of Intelligence and Counterintelligence Office of Intelligence and Counterintelligence Services Science & Innovation Mission About Us About Us Home News & Blog Offices You are here Home » Vacancy Announcement Vacancy Announcement Job Announcement Number: 16-0003 Who May Apply: All qualified U.S. citizens Duty Location: Multiple vacancies; most positions are in Washington, DC Metro Area Annual Salary Range: Varies

  9. Vacancy announcements

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

    Vacancy announcements Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues » submit Vacancy announcements Join our team or tell a friend May 1, 2015 The site offers a variety of Los Alamos-developed biosurveillance tools that can be used for decision support in disease surveillance. The site offers a variety of Los Alamos-developed biosurveillance tools that can be used for decision support in disease surveillance. Contact Linda

  10. Vacancy announcement

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

    Vacancy announcement 16-ooo3 The mission of the U.S. Department of Energy's Office of Intelligence and Counterintelligence (DOE-IN) is to identify and mitigate threats to U.S. national security and the DOE Enterprise, and inform national security decision making through scientific and technical expertise. As a member of the DOE-IN team, you will play a key role in reducing the global security threat, strengthening the nuclear security infrastructure, and buttressing America's economic

  11. NETL: Vacancy Announcements

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

    Vacancy List Home > Careers > Job Opportunities NEED HELP APPLYING FOR A FEDERAL GOVERNMENT JOB? Getting a federal job can be a lengthy process, but the frequently asked questions ...

  12. Vacancies | Department of Energy

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

    Vacancies Vacancies Job Title: Interdisciplinary General Engineer/Physical Scientist Series and Grade: GS-0801/1301-09/11 Job Announcement Number: DOE-MP-16-LM-00095-DE https://www.usajobs.gov/GetJob/ViewDetails/445527600 Closing Date: Friday, August 5, 2016 Job Title: Interdisciplinary General Engineer/Physical Scientist Series and Grade: GS-0801/1301-09/11 Job Announcement Number: DOE-MP-16-LM-00095-MP https://www.usajobs.gov/GetJob/ViewDetails/445506900/ Closing Date: Monday, August 8,

  13. Vacancy Announcement | Department of Energy

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

    Vacancy Announcement Vacancy Announcement Job Announcement Number: 16-0003 Who May Apply: All qualified U.S. citizens Duty Location: Multiple vacancies; most positions are in Washington, DC Metro Area Annual Salary Range: Varies according to specific position Open Period: Varies according to specific position Position Information: Varies according to specific position Job Description Available for Download General Vacancy 16-0003 (32.32 KB) Submit Resume To submit your resume for general

  14. Vacancies in fully hydrogenated boron nitride layer: implications for functional nanodevices

    SciTech Connect (OSTI)

    Zhou, Yungang; Wang, Zhiguo; Nie, JL; Yang, Ping; Sun, Xin; Khaleel, Mohammad A.; Zu, Xiaotao; Gao, Fei

    2012-03-01

    Using density functional theory, a series of calculations of structural and electronic properties of hydrogen vacancies in a fully hydrogenated boron nitride (fH-BN) layer were conducted. By dehydrogenating the fH-BN structure, B-terminated vacancies can be created which induce complete spin polarization around the Fermi level, irrespective of the vacancy size. On the contrary, the fH-BN structure with N-terminated vacancies can be a small-gap semiconductor, a typical spin gapless semiconductor, or a metal depending on the vacancy size. Utilizing such vacancy-induced band gap and magnetism changes, possible applications in spintronics are proposed, and a special fH-BN based quantum dot device is designed.

  15. Status

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

    ... 81% - NASA Account Management System (NAMS) Integration: 70% - Authentication Integration: 21% (complete Sep 2011) * Benefits today - Smartcard login to the desktop, then get to ...

  16. Status

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

    9 FOIA - Request Log 1 Closed/ Date No. Dated Date Rec'd HQ or Dir. Subject Finalized 05/19/09 001 04/07/09 04/07/09 Direct Current contracts with Visionary Solutions, LLC and CAST Specialty Transportation Incorporated, for transportation services for the Waste Isolation Pilot Plant (WIPP) Finalized 06/30/09 002 06/29/09 06/29/09 Transfer DOE/HQ (1) All documents dated from February 2001 to the present relating or referring to any labor disputes that have delayed completion of federal

  17. Strain Control of Oxygen Vacancies in Epitaxial Strontium Cobaltite...

    Office of Scientific and Technical Information (OSTI)

    Strain Control of Oxygen Vacancies in Epitaxial Strontium Cobaltite Films Citation Details In-Document Search Title: Strain Control of Oxygen Vacancies in Epitaxial Strontium ...

  18. Vacancy induced structural changes in diamond.

    SciTech Connect (OSTI)

    Barnard, A.; Sternberg, M.; Univ. of Melbourne

    2008-01-01

    Although optically active defects in nanodiamond are being considered as candidates for optical labeling in biomedical applications, development in this area is being hindered the fact that suitable defects are rarely seen in diamond nanoparticles in the size regime required. These defects usually form as a complex with an impurity and a neutral of charged vacancy, so a measurable concentration of vacancy point defects is also necessary. Presented here are results of density functional tight binding computer simulations investigating the stability of vacancies in diamond nanoparticles with different surface structures. The results indicate that both neutral and charged vacancies alter the structure of as-grown diamond nanoparticles and are likely to diffuse out of the particle during synthesis or irradiation. We also find that suitable passivation of the particle may alleviate this problem, and hence facilitate the formation of defect complexes.

  19. EERE Job Vacancies | Department of Energy

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

    Job Vacancies EERE Job Vacancies Photo of James Forrestal Building in downtown Washington, D.C., headquarters of the U.S. Department of Energy. Do you want to build your career while changing America? EERE, the U.S. Department of Energy office leading the nation's effort to enhance energy efficiency and develop renewable energy technologies, is searching for enthusiastic, driven and committed professionals to fill the following vacant positions. To apply for a job, follow the instructions

  20. Method for providing oxygen ion vacancies in lanthanide oxides

    DOE Patents [OSTI]

    Kay, D. Alan R.; Wilson, William G.

    1989-12-05

    A method for desulfurization of fuel gases resulting from the incomplete combustion of sulfur containing hydrocarbons whereby the gases are treated with lanthanide oxides containing large numbers of oxygen-ion vacancies providing ionic porosity which enhances the ability of the lanthanide oxides to react more rapidly and completely with the sulfur in the fuel gases whereby the sulfur in such gases is reduced to low levels suitable for fuels for firing into boilers of power plants generating electricity with steam turbine driven generators, gas turbines, fuel cells and precursors for liquid fuels such as methanol and the like.

  1. Vacancy-Driven Anisotropic Defect Distribution in the Battery...

    Office of Scientific and Technical Information (OSTI)

    Vacancy-Driven Anisotropic Defect Distribution in the Battery-Cathode Material LiFePO4 Citation Details In-Document Search Title: Vacancy-Driven Anisotropic Defect Distribution in ...

  2. Vacancy sharing in strongly asymmetric heavy-ion collisions

    SciTech Connect (OSTI)

    Janev, R.K.; Krstic', P.S.; Rakovic', M.J.

    1987-04-15

    A complex-energy, complex-interaction Nikitin-like model is proposed to describe the vacancy-sharing process when many quasimolecular states are strongly coupled. The vacancy-sharing ratio is obtained in closed analytical form. The general result is used to calculate the L-K vacancy sharing in the C/sup +/+Ar, N/sup +/+Ar, and O/sup +/+Ar collisions.

  3. DOE seeks candidates for environmental advisory board vacancies

    Broader source: Energy.gov [DOE]

    OREM is seeking volunteers to fill vacancies on the Oak Ridge Site Specific Advisory Board. Applications are due by Dec. 31.

  4. Probing oxygen vacancy concentration and homogeneity in solid...

    Office of Scientific and Technical Information (OSTI)

    Here, we develop an approach for direct mapping of oxygen vacancy concentrations based on local lattice parameter measurements by scanning transmission electron microscopy. The ...

  5. Strain control of oxygen vacancies in epitaxial strontium cobaltite...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Strain control of oxygen vacancies in epitaxial strontium cobaltite films ... This content will become publicly available on January 25, 2017 Title: Strain control of ...

  6. Stiffness and strength of oxygen-functionalized graphene with vacancies

    SciTech Connect (OSTI)

    Zandiatashbar, A.; Ban, E.; Picu, R. C.

    2014-11-14

    The 2D elastic modulus (E{sup 2D}) and strength (?{sup 2D}) of defective graphene sheets containing vacancies, epoxide, and hydroxyl functional groups are evaluated at 300?K by atomistic simulations. The fraction of vacancies is controlled in the range 0% to 5%, while the density of functional groups corresponds to O:C ratios in the range 0% to 25%. In-plane modulus and strength diagrams as functions of vacancy and functional group densities are generated using models with a single type of defect and with combinations of two types of defects (vacancies and functional groups). It is observed that in models containing only vacancies, the rate at which strength decreases with increasing the concentration of defects is largest, followed by models containing only epoxide groups and those with only hydroxyl groups. The effect on modulus of vacancies and epoxides present alone in the model is similar, and much stronger than that of hydroxyl groups. When the concentration of defects is large, the combined effect of the functional groups and vacancies cannot be obtained as the superposition of individual effects of the two types of defects. The elastic modulus deteriorates faster (slower) than predicted by superposition in systems containing vacancies and hydroxyl groups (vacancies and epoxide groups)

  7. The Electronic Structure of Oxygen Atom Vacancy and Hydroxyl...

    Office of Scientific and Technical Information (OSTI)

    Title: The Electronic Structure of Oxygen Atom Vacancy and Hydroxyl Impurity Defects on Titanium Dioxide (110) Surface Introducing a charge into a solid such as a metal oxide ...

  8. Vacancy Announcement Posted for Fuel Cell Technologies Office

    Broader source: Energy.gov [DOE]

    The Fuel Cell Technologies Office has posted a vacancy announcement for a position in the Hydrogen Safety, Codes, and Standards program.

  9. Exploring Mesoscopic Physics of Vacancy-Ordered Systems through...

    Office of Scientific and Technical Information (OSTI)

    Exploring Mesoscopic Physics of Vacancy-Ordered Systems through Atomic Scale Observations of Topological Defects Citation Details In-Document Search Title: Exploring Mesoscopic ...

  10. Oxidation State and Interfacial Effects on Oxygen Vacancies in...

    Office of Scientific and Technical Information (OSTI)

    Oxygen Vacancies in Tantalum Pentoxide. Abstract not provided. Authors: Bondi, Robert James ; Marinella, Matthew Publication Date: 2014-10-01 OSTI Identifier: 1184499 Report...

  11. Completed EISs | Department of Energy

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

    Completed EISs Completed EISs Comprehensive EIS list Completed EISs (406.76 KB) More Documents & Publications Environmental Impact Statements and Environmental Assessments Status Chart NEPA Documentation 2011 ANNUAL PLANNING SUMMARY FOR ADVANCED RESEARCH AND PROJECTS AGENCY WESTERN AREA POWER ADMINISTRATION

  12. Vacancy-controlled ultrastable nanoclusters in nanostructured ferritic alloys

    SciTech Connect (OSTI)

    Zhang, Z. W.; Yao, L.; Wang, X. -L.; Miller, M. K.

    2015-05-29

    A new class of advanced structural materials, based on the Fe-O-vacancy system, has exceptional resistance to high-temperature creep and excellent tolerance to extremely high-dose radiation. Although these remarkable improvements in properties compared to steels are known to be associated with the Y-Ti-O-enriched nanoclusters, the roles of vacancies in facilitating the nucleation of nanoclusters are a long-standing puzzle, due to the experimental difficulties in characterizing vacancies, particularly in-situ while the nanoclusters are forming. We report an experiment study that provides the compelling evidence for the presence of significant concentrations of vacancies in Y-Ti-O-enriched nanoclusters in a nanostructured ferritic alloy using a combination of state-of-the-art atom-probe tomography and in situ small angle neutron scattering. The nucleation of nanoclusters starts from the O-enriched solute clustering with vacancy mediation. The nanoclusters grow with an extremely low growth rate through attraction of vacancies and O:vacancy pairs, leading to the unusual stability of the nanoclusters.

  13. Vacancy-controlled ultrastable nanoclusters in nanostructured ferritic alloys

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

    Zhang, Z. W.; Yao, L.; Wang, X. -L.; Miller, M. K.

    2015-05-29

    A new class of advanced structural materials, based on the Fe-O-vacancy system, has exceptional resistance to high-temperature creep and excellent tolerance to extremely high-dose radiation. Although these remarkable improvements in properties compared to steels are known to be associated with the Y-Ti-O-enriched nanoclusters, the roles of vacancies in facilitating the nucleation of nanoclusters are a long-standing puzzle, due to the experimental difficulties in characterizing vacancies, particularly in-situ while the nanoclusters are forming. We report an experiment study that provides the compelling evidence for the presence of significant concentrations of vacancies in Y-Ti-O-enriched nanoclusters in a nanostructured ferritic alloy using amore » combination of state-of-the-art atom-probe tomography and in situ small angle neutron scattering. The nucleation of nanoclusters starts from the O-enriched solute clustering with vacancy mediation. The nanoclusters grow with an extremely low growth rate through attraction of vacancies and O:vacancy pairs, leading to the unusual stability of the nanoclusters.« less

  14. DOE seeks candidates for environmental advisory board vacancies

    Broader source: Energy.gov [DOE]

    OAK RIDGE, Tenn.—The Department of Energy’s Oak Ridge Office of Environmental Management is seeking volunteers to fill vacancies on the Oak Ridge Site Specific Advisory Board (ORSSAB).

  15. Role of an Oxygen Vacancy Nanostructure on the Switchable Photovoltaic...

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

    Role of an Oxygen Vacancy Nanostructure on the Switchable Photovoltaic Effect in BiFeO3 ... Moreover, a switchable photovoltaic effect and its diode effect have been demonstrated.2 ...

  16. Vacancy Announcements Posted for Hydrogen Production and Delivery Program

    Broader source: Energy.gov [DOE]

    The Fuel Cell Technologies Office has posted two vacancy announcements for a position to serve as Program Manager for the Hydrogen Production and Delivery Program in the DOE EERE Fuel Cell Technologies Office. The closing date is October 28, 2014.

  17. Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers

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

    Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Wednesday, 21 December 2005 00:00 Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features

  18. Interaction of light with the ZnO surface: Photon induced oxygen breathing, oxygen vacancies, persistent photoconductivity, and persistent photovoltage

    SciTech Connect (OSTI)

    Gurwitz, Ron; Cohen, Rotem; Shalish, Ilan

    2014-01-21

    completes the vacancy to become a full ZnO molecule vacancy, which does not produce deep levels. Our results explain why ZnO finds use as an electrical detector for oxygen and for carbon containing gas molecules. They may also shed new light on photocatalytic uses of ZnO. It is suggested that similar surface phenomena may affect other semiconducting oxides.

  19. Completed EISs

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

    Completed EISs Number of EISs in report: 294 Number Title Prog Office Ops Office Federal Register Notices Notice Date Citation Agency Areva Eagle Rock Enrichment Facility, Bonneville County, Idaho (Adopted) LP DOE/EIS-0471 5/20/2011 EPA 76 FR 29240 Adopted American Centrifuge Plant in Piketon, Pike County, Ohio (Adopted) LP DOE/EIS-0468 5/20/2011 EPA 76 FR 29240 Adopted Cushman Hydroelectric Project, Mason County, Washington (Adopted) EE DOE/EIS-0456 10/8/2010 EPA 75 FR 62386 NOA FEIS 11/29/2010

  20. Legacy Clean-up Completion Project Overview | Department of Energy

    Office of Environmental Management (EM)

    Legacy Clean-up Completion Project Overview Legacy Clean-up Completion Project Overview Topic: Bob Pfaff provided the members with information regarding the status of the Fiscal ...

  1. Chemistry - Oxygen Vacancies and Catalysis on Ceria Surfaces

    SciTech Connect (OSTI)

    Campbell, Charles T.; Peden, Charles HF.

    2005-07-29

    Chemistry occurring at the surface of metal oxides is critical in a variety of industrial applications including catalysis and photocatalysis, optical display technology, solar energy devices and corrosion prevention. Defects have long been recognized to be the most reactive sites on the surfaces of many oxide materials. The most common types of defects present on the surfaces of metal oxides are oxygen vacancies and step edges. The nature of surface oxygen vacancies, and their number, distribution and diffusion across the surface of oxides, are thus issues of major scientific importance. One of the most interesting oxides in this respect is CeO2, since oxygen vacancies play the key role in giving this material it's industrially important ''oxygen-storage capacity''. This capacity makes modern automotive exhaust treatment catalysts containing CeO2 much more effective than their predecessors without CeO2. Ceria is also well known as a support which enhances the performance of transition metal catalysts, relative to other oxide supports, in a variety of other reactions including water-gas shift, steam reforming of oxygenates and PROX 1-7, all of which hold promise for enabling a hydrogen economy 1. Related to ceria's facile redox capacity (ability to rapidly form and eliminate oxygen vacancy defects) is the poorly understood observation that some less reducible oxides, such as zirconia (ZrO2), are used as additives that actually enhance this ''oxygen storage'' property of CeO2. In this issue, Esch and coworkers in Trieste, Italy report an exciting study that for the first time clearly elucidates the structure, distribution and formation of oxygen vacancies on a cerium oxide surface 8. They have elegantly combined beautiful, atomic-resolution imaging using scanning-tunneling microscopy (STM) on a ceria surface with state-of-the-art quantum mechanical calculations using Density Functional Theory (DFT) to raise our understanding of CeO2 surfaces to a much higher level

  2. Chemical expansion affected oxygen vacancy stability in different oxide structures from first principles calculations

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

    Aidhy, Dilpuneet S.; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2015-01-21

    We study the chemical expansion for neutral and charged oxygen vacancies in fluorite, rocksalt, perovskite and pyrochlores materials using first principles calculations. We show that the neutral oxygen vacancy leads to lattice expansion whereas the charged vacancy leads to lattice contraction. In addition, we show that there is a window of strain within which an oxygen vacancy is stable; beyond that range, the vacancy can become unstable. Using CeO2|ZrO2 interface structure as an example, we show that the concentration of oxygen vacancies can be manipulated via strain, and the vacancies can be preferentially stabilized. Furthermore, these results could serve asmore » guiding principles in predicting oxygen vacancy stability in strained systems and in the design of vacancy stabilized materials.« less

  3. Chemical expansion affected oxygen vacancy stability in different oxide structures from first principles calculations

    SciTech Connect (OSTI)

    Aidhy, Dilpuneet S.; Liu, Bin; Zhang, Yanwen; Weber, William J.

    2015-03-01

    We study the chemical expansion for neutral and charged oxygen vacancies in fluorite, rocksalt, perovskite and pyrochlores materials using first principles calculations. We show that the neutral oxygen vacancy leads to lattice expansion whereas the charged vacancy leads to lattice contraction. In addition, we show that there is a window of strain within which an oxygen vacancy is stable; beyond that range, the vacancy can become unstable. Using CeO2|ZrO2 interface structure as an example, we show that the concentration of oxygen vacancies can be manipulated via strain, and the vacancies can be preferentially stabilized. These results could serve as guiding principles in predicting oxygen vacancy stability in strained systems and in the design of vacancy stabilized materials.

  4. Mechanism of vacancy formation induced by hydrogen in tungsten

    SciTech Connect (OSTI)

    Liu, Yi-Nan; Association EURATOM-TEKES, University of Helsinki, Helsinki, PO Box 64, 00560 ; Ahlgren, T.; Bukonte, L.; Nordlund, K.; Shu, Xiaolin; Yu, Yi; Lu, Guang-Hong; Li, Xiao-Chun

    2013-12-15

    We report a hydrogen induced vacancy formation mechanism in tungsten based on classical molecular dynamics simulations. We demonstrate the vacancy formation in tungsten due to the presence of hydrogen associated directly with a stable hexagonal self-interstitial cluster as well as a linear crowdion. The stability of different self-interstitial structures has been further studied and it is particularly shown that hydrogen plays a crucial role in determining the configuration of SIAs, in which the hexagonal cluster structure is preferred. Energetic analysis has been carried out to prove that the formation of SIA clusters facilitates the formation of vacancies. Such a mechanism contributes to the understanding of the early stage of the hydrogen blistering in tungsten under a fusion reactor environment.

  5. Orbital reconstruction in a self-assembled oxygen vacancy nanostructure

    SciTech Connect (OSTI)

    Jang, H.; Kerr, G.; Lim, J. S.; Yang, C. -H.; Kao, C. -C.; Lee, J. -S.

    2015-07-27

    We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1nm) in BiFeO₃, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca²⁺ for Bi³⁺ cation. We found that by increasing the substitution, the in-plane orbital bands of Fe³⁺ cations are reconstructed without any redox reaction. It leads to a reduction of the hopping between Fe atoms, forming a localized valence band, in particular Fe 3d-electronic structure, around the Fermi level. This band localization causes to decrease the conductivity of the doped BiFeO₃ system.

  6. Orbital reconstruction in a self-assembled oxygen vacancy nanostructure

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

    Jang, H.; Kerr, G.; Lim, J. S.; Yang, C. -H.; Kao, C. -C.; Lee, J. -S.

    2015-07-27

    We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1nm) in BiFeO₃, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca²⁺ for Bi³⁺ cation. We found that by increasing the substitution, the in-plane orbital bands of Fe³⁺ cations are reconstructed without any redox reaction. It leads to a reduction of the hopping between Fe atoms, forming a localized valence band, in particular Fe 3d-electronic structure, around the Fermi level. This band localization causes to decrease the conductivity of themore » doped BiFeO₃ system.« less

  7. GUIDANCE ON APPLICATION OF FEDERAL VACANCIES REFORM ACT OF 1998 Page 1 of 13

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

    APPLICATION OF FEDERAL VACANCIES REFORM ACT OF 1998 Page 1 of 13 GUIDANCE ON APPLICATION OF FEDERAL VACANCIES REFORM ACT OF 1998 This memorandum provides guidance on the application of the Federal Vacancies Reform Act of1998 to vacancies in Senate-confirmed offices within the executive branch. March 22, 1999 MEMORANDUM FOR AGENCY GENERAL COUNSELS On October 21, 1998, the Federal Vacancies Reform Act of 1998 ("Vacancies Reform Act" or "Act") was signed into law. ( ) The

  8. Vacancy dynamic in Ni-Mn-Ga ferromagnetic shape memory alloys

    SciTech Connect (OSTI)

    Merida, D.; Snchez-Alarcos, V.; Prez-Landazbal, J. I.; Recarte, V.; Plazaola, F.

    2014-06-09

    Vacancies control any atomic ordering process and consequently most of the order-dependent properties of the martensitic transformation in ferromagnetic shape memory alloys. Positron annihilation spectroscopy demonstrates to be a powerful technique to study vacancies in NiMnGa alloys quenched from different temperatures and subjected to post-quench isothermal annealing treatments. Considering an effective vacancy type the temperature dependence of the vacancy concentration has been evaluated. Samples quenched from 1173?K show a vacancy concentration of 1100??200?ppm. The vacancy migration and formation energies have been estimated to be 0.55??0.05?eV and 0.90??0.07?eV, respectively.

  9. Live Status

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

    For Users Live Status Queue Look Classic Queue Look Scheduled Outages Outage Log Science Gateway Status Login Node Status Filesystem Status My NERSC Move to CRT Getting Started...

  10. Property:CSC-Status | Open Energy Information

    Open Energy Info (EERE)

    navigation, search Property Name CSC-Status Property Type String Description Geothermal Case Study Challenge (CSC) sign-up status Allows Values Available;Completed;Selected Pages...

  11. Beam Status

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

    Beam Status Beam Status Print Loading... You can also view the Operations Group's Beam History archives.

  12. Guidance_Application_Federal_Vacancies_Reform_Act_1998.pdf | Department of

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

    Energy Guidance_Application_Federal_Vacancies_Reform_Act_1998.pdf Guidance_Application_Federal_Vacancies_Reform_Act_1998.pdf Guidance_Application_Federal_Vacancies_Reform_Act_1998.pdf (2.66 MB) More Documents & Publications Intelligence Reform and Terrorism Prevention Act - December 17, 2004 Bond Amendment, Security Clearances - January 1, 2008 National Historic Preservation Act (1966, amended 2014)

  13. Vacancies in ordered and disordered titanium monoxide: Mechanism of B1 structure stabilization

    SciTech Connect (OSTI)

    Kostenko, M.G.; Lukoyanov, A.V.; Zhukov, V.P.; Rempel, A.A.

    2013-08-15

    The electronic structure and stability of three phases of titanium monoxide TiO{sub y} with B1 type of the basic structure have been studied. Cubic phase without structural vacancies, TiO, and two phases with structural vacancies, monoclinic Ti{sub 5}O{sub 5} and cubic disordered TiO{sub 1.0}, was treated by means of first-principles calculations within the density functional theory with pseudo-potential approach based on the plane wave's basis. The ordered monoclinic phase Ti{sub 5}O{sub 5} was found to be the most stable and the cubic TiO without vacancies the less stable one. The role of structural vacancies in the titanium sublattice is to decrease the Fermi energy, the role of vacancies in the oxygen sublattice is to contribute to the appearance of Ti–Ti bonding interactions through these vacancies and to reinforce the Ti–Ti interactions close to them. Listed effects are significantly pronounced if the vacancies in the titanium and oxygen sublattices are associated in the so called “vacancy channels” which determine the formation of vacancy ordered structure of monoclinic Ti{sub 5}O{sub 5}-type. - Graphical abstract: Changes in total DOS of titanium monoxide when going from vacancy-free TiO to TiO with disordered structural vacancies and to TiO with ordered structural vacancies. Highlights: • Ordered monoclinic Ti{sub 5}O{sub 5} is the most stable phase of titanium monoxide. • Vacancy-free TiO is the less stable phase of the titanium monoxide. • Ordering of oxygen vacancies leads to the appearance of Ti–Ti bonding interactions. • Titanium vacancies contribute significantly to the decreasing of the Fermi energy.

  14. Active DOE Completed Projects

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

    Completed) Project Number Title Document ID SLM / ORG Author / Phone / Email Status / Review Date P1137-2007REV Fire ProtecƟon Engineering FAQS DOE-STD-1137-2014 Karen Boardman (NNSA) P1181-2004REV Facility Maintenance Management DOE-STD-1181-2014 Karen Boardman FuncƟon Area QualiĮcaƟon Standard (HS-70) P1182-2004REV Civil Structural Engineering, FuncƟonal DOE-STD-1182-2014 Karen Boardman Area QualiĮcaƟon Standard (AU-70) P2013-03 ProtecƟve Force ConƟngency Planning DOE-HDBK-1213-2014

  15. Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers

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

    Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the

  16. Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers

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

    Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the

  17. Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers

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

    Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the

  18. Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers

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

    Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the

  19. Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers

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

    Vacancy-Induced Nanoscale Wire Structure in Gallium Selenide Layers Print Low-dimensional materials have gained much attention not only because of the nonstop march toward miniaturization in the electronics industry but also for the exotic properties that are inherent in their small size. One approach for creating low-dimensional structures is to exploit the nanoscale or atomic-scale features that exist naturally in the three-dimensional (bulk) form of materials. By this means, a group from the

  20. Real Space Mapping of Oxygen Vacancy Diffusion and Electrochemical

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

    Transformations by Hysteretic Current Reversal Curve Measurements - Energy Innovation Portal Hydrogen and Fuel Cell Hydrogen and Fuel Cell Energy Storage Energy Storage Find More Like This Return to Search Real Space Mapping of Oxygen Vacancy Diffusion and Electrochemical Transformations by Hysteretic Current Reversal Curve Measurements Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryElectrochemical energy storage and conversion systems based on

  1. DOE seeks candidates for advisory board vacancies | Department of Energy

    Energy Savers [EERE]

    February 24, 2016 - 2:06pm Addthis OAK RIDGE, Tenn. - The Department of Energy's (DOE) Oak Ridge Office of Environmental Management is seeking volunteers to fill vacancies on the Oak Ridge Site Specific Advisory Board (ORSSAB). The board is a federally chartered citizens' panel that provides recommendations to the agency regarding cleanup activities across the Oak Ridge Reservation. The deadline for submitting applications is March 15. Chartered in 1995 under the Federal Advisory Committee Act,

  2. Strain control of oxygen vacancies in epitaxial strontium cobaltite films

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

    Jeen, Hyoung Jeen; Choi, Woo Seok; Reboredo, Fernando A.; Freeland, John W.; Eres, Gyula; Lee, Ho Nyung; Petrie, Jonathan R.; Mitra, Chandrima; Meyer, Tricia L.

    2016-01-25

    In this study, the ability to manipulate oxygen anion defects rather than metal cations in complex oxides can facilitate creating new functionalities critical for emerging energy and device technologies. However, the difficulty in activating oxygen at reduced temperatures hinders the deliberate control of important defects, oxygen vacancies. Here, strontium cobaltite (SrCoOx) is used to demonstrate that epitaxial strain is a powerful tool for manipulating the oxygen vacancy concentration even under highly oxidizing environments and at annealing temperatures as low as 300 °C. By applying a small biaxial tensile strain (2%), the oxygen activation energy barrier decreases by ≈30%, resulting inmore » a tunable oxygen deficient steady-state under conditions that would normally fully oxidize unstrained cobaltite. These strain-induced changes in oxygen stoichiometry drive the cobaltite from a ferromagnetic metal towards an antiferromagnetic insulator. The ability to decouple the oxygen vacancy concentration from its typical dependence on the operational environment is useful for effectively designing oxides materials with a specific oxygen stoichiometry.« less

  3. Lattice distortions and oxygen vacancies produced in Au+ irradiated nano-crystalline cubic zirconia

    SciTech Connect (OSTI)

    Edmondson, Philip D; Weber, William J; Namavar, Fereydoon; Zhang, Yanwen

    2011-01-01

    The structural impact of oxygen vacancies in nanocrystalline cubic zirconia is investigated. A non-equilibrium number of oxygen vacancies in introduced to the lattice by ion irradiation. The lattice is observed to be initially compressed, undergoes a relaxation at 0.7 displacements per atom (dpa), and experiences a contraction before reaching a temperature dependent steady state value at above 7 dpa. The level of lattice distortion is related to the charge state of the accumulating oxygen vacancies.

  4. Oxygen vacancy ordering within anion-deficient Ceria

    SciTech Connect (OSTI)

    Hull, S.; Norberg, S.T.; Ahmed, I.; Eriksson, S.G.; Marrocchelli, D.; Madden, P.A.

    2009-10-15

    The structural properties of anion deficient ceria, CeO{sub 2-{delta}}, have been studied as a function of oxygen partial pressure, p(O{sub 2}), over the range 0>=log{sub 10p}(O{sub 2})>=-18.9 at 1273(2) K using the neutron powder diffraction technique. Rietveld refinement of the diffraction data collected on decreasing p(O{sub 2}) showed increases in the cubic lattice parameter, a, the oxygen nonstoichiometry, delta, and the isotropic thermal vibration parameters, u{sub Ce} and u{sub O}, starting at log{sub 10p}(O{sub 2}){approx}-11. The increases are continuous, but show a distinct kink at log{sub 10p}(O{sub 2}){approx}-14.5. Analysis of the total scattering (Bragg plus diffuse components) using reverse Monte Carlo (RMC) modelling indicates that the O{sup 2-} vacancies preferentially align as pairs in the <111> cubic directions as the degree of nonstoichiometry increases. This behaviour is discussed with reference to the chemical crystallography of the CeO{sub 2}-Ce{sub 2}O{sub 3} system at ambient temperature and, in particular, to the nature of the long-range ordering of O{sup 2-} vacancies within the crystal structure of Ce{sub 7}O{sub 12}. - Graphical abstract: Partial radial distribution function for oxygen vacancies within CeO{sub 1.710} at 1273 K (solid line) showing the increased tendency for local ordering in <111> directions compared to a random distribution (dashed line).

  5. Alignment of the diamond nitrogen vacancy center by strain engineering

    SciTech Connect (OSTI)

    Karin, Todd [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Dunham, Scott [Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States); Fu, Kai-Mei [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States)

    2014-08-04

    The nitrogen vacancy (NV) center in diamond is a sensitive probe of magnetic field and a promising qubit candidate for quantum information processing. The performance of many NV-based devices improves by aligning the NV(s) parallel to a single crystallographic direction. Using ab initio theoretical techniques, we show that NV orientation can be controlled by high-temperature annealing in the presence of strain under currently accessible experimental conditions. We find that (89??7)% of NVs align along the [111] crystallographic direction under 2% compressive biaxial strain (perpendicular to [111]) and an annealing temperature of 970?C.

  6. Lattice Distortions and Oxygen Vacancies Produced in Au+-Irradiated Nanocrystalline Cubic Zirconia

    SciTech Connect (OSTI)

    Edmondson, P. D.; Weber, William J.; Namavar, Fereydoon; Zhang, Yanwen

    2011-07-13

    The oxygen ion conductivity, attributed to an oxygen vacancy mechanism, of yttria-stabilized zirconia membranes used in solid oxide fuel cells is restricted due to trapping limitations. In this work, a high concentration of oxygen vacancies has been deliberately introduced into nanocrystalline stabilizer-free zirconia through ion-irradiation. Oxygen vacancies with different charge states can be produced by varying irradiation temperatures. Due to the reduced trapping sites and high oxygen vacancy concentration, this work suggests that the efficiency of solid oxide fuel cells can be improved.

  7. Vacancy defects in as-grown and neutron irradiated GaP studied by positrons

    SciTech Connect (OSTI)

    Dlubek, G.; Bruemmer, O.; Polity, A.

    1986-08-18

    Positron lifetime and Doppler-broadening measurements have been used to study vacancy defects in n-italic-type GaP. Vacancies in the P sublattice with a concentration of some 10/sup 17/ cm/sup -3/ were observed in as-grwon GaP. The vacancies disappear during annealing at 500--800 /sup 0/C. In neutron-irradiated GaP positrons are trapped by Ga vacancies which anneal out in two stages situated at 300--550 /sup 0/C and 550--700 /sup 0/C.

  8. Migration of defect clusters and xenon-vacancy clusters in uranium dioxide

    SciTech Connect (OSTI)

    Chen, Dong; Gao, Fei; Deng, Huiqiu; Hu, Wangyu; Sun, Xin

    2014-07-01

    The possible transition states, minimum energy paths and migration mechanisms of defect clusters and xenon-vacancy defect clusters in uranium dioxide have been investigated using the dimer and the nudged elastic-band methods. The nearby O atom can easily hop into the oxygen vacancy position by overcoming a small energy barrier, which is much lower than that for the migration of a uranium vacancy. A simulation for a vacancy cluster consisting of two oxygen vacancies reveals that the energy barrier of the divacancy migration tends to decrease with increasing the separation distance of divacancy. For an oxygen interstitial, the migration barrier for the hopping mechanism is almost three times larger than that for the exchange mechanism. Xe moving between two interstitial sites is unlikely a dominant migration mechanism considering the higher energy barrier. A net migration process of a Xe-vacancy pair containing an oxygen vacancy and a xenon interstitial is identified by the NEB method. We expect the oxygen vacancy-assisted migration mechanism to possibly lead to a long distance migration of the Xe interstitials in UO2. The migration of defect clusters involving Xe substitution indicates that Xe atom migrating away from the uranium vacancy site is difficult.

  9. Metallic filament formation by aligned oxygen vacancies in ZnO-based resistive switches

    SciTech Connect (OSTI)

    Gu, Tingkun

    2014-05-28

    The electronic structure of ZnO with defects of oxygen vacancies were investigated by using first-principles methods. Some structure models were constructed in order to investigate the effects of the distribution of oxygen vacancies on the electronic properties of ZnO. By analyzing the calculated results, we found that only the aligned oxygen vacancies can form the conducting channel in ZnO, and the transformation of the oxygen vacancy from charged state to neutral state is consistent with the energetics rule of the forming aligned oxygen vacancies. As for the heterojunction of Pt/ZnO/Pt, the oxygen vacancies near the interface of Pt/ZnO depress the local Schottky barrier effectively, and the aligned oxygen vacancies in ZnO form a conducting filament connecting two Pt electrodes. The metallic filament formation in Pt/ZnO/Pt resistive switching cells should be closely related to the carrier injection from Pt electrode into ZnO and the arrangement of oxygen vacancies in ZnO slab.

  10. Beam Status

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

    Beam Status Print Loading... You can also view the Operations Group's Beam History archives

  11. Coloration and oxygen vacancies in wide band gap oxide semiconductors: Absorption at metallic nanoparticles induced by vacancy clustering—A case study on indium oxide

    SciTech Connect (OSTI)

    Albrecht, M. Schewski, R.; Irmscher, K.; Galazka, Z.; Markurt, T.; Naumann, M.; Schulz, T.; Uecker, R.; Fornari, R.; Meuret, S.; Kociak, M.

    2014-02-07

    In this paper, we show by optical and electron microscopy based investigations that vacancies in oxides may cluster and form metallic nanoparticles that induce coloration by extinction of visible light. Optical extinction in this case is caused by generation of localized surface plasmon resonances at metallic particles embedded in the dielectric matrix. Based on Mie's approach, we are able to fit the absorption due to indium nanoparticles in In{sub 2}O{sub 3} to our absorption measurements. The experimentally found particle distribution is in excellent agreement with the one obtained from fitting by Mie theory. Indium particles are formed by precipitation of oxygen vacancies. From basic thermodynamic consideration and assuming theoretically calculated activation energies for vacancy formation and migration, we find that the majority of oxygen vacancies form just below the melting point. Since they are ionized at this temperature they are Coulomb repulsive. Upon cooling, a high supersaturation of oxygen vacancies forms in the crystal that precipitates once the Fermi level crosses the transition energy level from the charged to the neutral charge state. From our considerations we find that the ionization energy of the oxygen vacancy must be higher than 200 meV.

  12. Computer simulation study of the structure of vacancies in grain boundaries

    SciTech Connect (OSTI)

    Brokman, A.; Bristowe, P.D.; Balluffi, R.W.

    1981-01-01

    The structure of vacancies in grain boundaries has been investigated by computer molecular statics employing pairwise potentials. In order to gain an impression of the vacancy structures which may occur generally, a number of variables was investigated including: metal type, boundary type, degree of lattice coincidence and choice of boundary site. In all cases the vacancies remained as distinguishable point defects in the relatively irregular boundary structures. However, it was found that the vacancy often induced relatively large atomic displacements in the core of the boundary. These displacements often occurred only in the direct vicinity of the vacancy, but in certain cases they were widely distributed in the boundary, sometimes at surprisingly large distances.

  13. Ab initio study of formation, migration and binding properties of helium-vacancy clusters in aluminum

    SciTech Connect (OSTI)

    Yang, Li; Zu, Xiaotao T.; Gao, Fei

    2008-08-01

    Ab initio calculations based on density functional theory have been performed to study the dissolution and migration of helium, and the stability of small helium-vacancy clusters HenVm (n, m=0 to 4) in aluminum. The results indicate that the octahedral configuration is more stable than the tetrahedral. Interstitial helium atoms are predicted to have attractive interactions and jump between two octahedral sites via an intermediate tetrahedral site with low migration energy of 0.10 eV. The binding energies of an interstitial He atom and an isolated vacancy to a HenVm cluster are also obtained from the calculated formation energies of the clusters. We find that the divacancy and tri--vacancy clusters are not stable, but He atoms can increase the stability of vacancy clusters. The interactions of He atoms with a vacancy are found to be in good agreement with the experimental results.

  14. First principle study of structural, electronic and magnetic properties of zigzag boron nitride nanoribbon: Role of vacancies

    SciTech Connect (OSTI)

    Kumar, Arun; Bahadur, Amar; Mishra, Madhukar; Vasudeva, Neena

    2015-05-15

    We study the effect of vacancies on the structural, electronic and magnetic properties of zigzag boron nitride nanoribbon (ZBNNR) by using first principle calculations. We find that the shift of the vacancies with respect to the ribbon edges causes change in the structural geometry, electronic structure and magnetization of ZBNNR. These vacancies also produce band gap modulation and consequently results the magnetization of ZBNNR.

  15. Reaction Kinetics of Water Molecules with Oxygen Vacancies on Rutile TiO2(110)

    SciTech Connect (OSTI)

    Petrik, Nikolay G.; Kimmel, Gregory A.

    2015-09-16

    The formation of bridging hydroxyls (OHb) via reactions of water molecules with oxygen vacancies (VO) on reduced TiO2(110) surfaces is studied using infrared reflection-absorption spectroscopy (IRAS), electron-stimulated desorption (ESD), and photon-stimulated desorption (PSD). Narrow IRAS peaks at 2737 cm-1 and 3711 cm-1 are observed for stretching vibrations of ODb and OHb on TiO2(110), respectively. IRAS measurements with s- and p-polarized light demonstrate that the bridging hydroxyls are oriented normal to the (110) surface. The IR peaks disappear after the sample is exposed to O2 or annealed in the temperature range of 400 – 600 K (correlating with the temperature at which pairs of OHb’s reform water and then desorb), which is consistent with their identification as bridging hydroxyls. We have studied the kinetics of water reacting with the vacancies by monitoring the formation of bridging hydroxyls (using IRAS) as a function of the annealing temperature for a small amount of water initially dosed on the TiO2(110) at low temperature. Separate experiments have also monitored the loss of water molecules (using water ESD) and vacancies (using the CO photooxidation reaction) due to the reactions of water molecules with the vacancies. All three techniques show that the reaction rate becomes appreciable for T > 150 K and that the reactions largely complete for T > 250 K. The temperature-dependent water-VO reaction kinetics are consistent with a Gaussian distribution of activation energies with Ea = 0.545 eV, ΔEa(FWHM) = 0.125 eV, and a “normal” prefactor, v = 1012 s-1. In contrast, a single activation energy with a physically reasonable prefactor does not fit the data well. Our experimental activation energy is close to theoretical estimates for the diffusion of water molecules along the Ti5c rows on the reduced TiO2

  16. Strategies to Suppress Cation Vacancies in Metal Oxide Alloys: Consequences for Solar Energy Conversion

    SciTech Connect (OSTI)

    Toroker, Maytal; Carter, Emily A.

    2015-09-01

    First-row transition metal oxides (TMOs) are promising alternative materials for inexpensive and efficient solar energy conversion. However, their conversion efficiency can be deleteriously affected by material imperfections, such as atomic vacancies. In this work, we provide examples showing that in some iron-containing TMOs, iron cation vacancy formation can be suppressed via alloying. We calculate within density functional theory+U theory the iron vacancy formation energy in binary rock-salt oxide alloys that contain iron, manganese, nickel, zinc, and/or magnesium. We demonstrate that formation of iron vacancies is less favorable if we choose to alloy iron(II) oxide with metals that cannot readily accept vacancy-generated holes, e.g., magnesium, manganese, nickel, or zinc. Since there are less available sites for holes and the holes are forced to reside on iron cations, the driving force for iron vacancy formation decreases. These results are consistent with an experiment observing a sharp drop in cation vacancy concentration upon alloying iron(II) oxide with manganese.

  17. Impact of homogeneous strain on uranium vacancy diffusion in uranium dioxide

    SciTech Connect (OSTI)

    Goyal, Anuj; Phillpot, Simon R.; Subramanian, Gopinath; Andersson, David A.; Stanek, Chris R.; Uberuaga, Blas P.

    2015-03-03

    We present a detailed mechanism of, and the effect of homogeneous strains on, the migration of uranium vacancies in UO2. Vacancy migration pathways and barriers are identified using density functional theory and the effect of uniform strain fields are accounted for using the dipole tensor approach. We report complex migration pathways and noncubic symmetry associated with the uranium vacancy in UO2 and show that these complexities need to be carefully accounted for to predict the correct diffusion behavior of uranium vacancies. We show that under homogeneous strain fields, only the dipole tensor of the saddle with respect to the minimum is required to correctly predict the change in the energy barrier between the strained and the unstrained case. Diffusivities are computed using kinetic Monte Carlo simulations for both neutral and fully charged state of uranium single and divacancies. We calculate the effect of strain on migration barriers in the temperature range 800–1800 K for both vacancy types. Homogeneous strains as small as 2% have a considerable effect on diffusivity of both single and divacancies of uranium, with the effect of strain being more pronounced for single vacancies than divacancies. In contrast, the response of a given defect to strain is less sensitive to changes in the charge state of the defect. Further, strain leads to anisotropies in the mobility of the vacancy and the degree of anisotropy is very sensitive to the nature of the applied strain field for strain of equal magnitude. Our results indicate that the influence of strain on vacancy diffusivity will be significantly greater when single vacancies dominate the defect structure, such as sintering, while the effects will be much less substantial under irradiation conditions where divacancies dominate.

  18. Impact of homogeneous strain on uranium vacancy diffusion in uranium dioxide

    SciTech Connect (OSTI)

    Goyal, Anuj; Phillpot, Simon R.; Subramanian, Gopinath; Andersson, David A.; Stanek, Chris R.; Uberuaga, Blas P.

    2015-03-03

    We present a detailed mechanism of, and the effect of homogeneous strains on, the migration of uranium vacancies in UO2. Vacancy migration pathways and barriers are identified using density functional theory and the effect of uniform strain fields are accounted for using the dipole tensor approach. We report complex migration pathways and noncubic symmetry associated with the uranium vacancy in UO2 and show that these complexities need to be carefully accounted for to predict the correct diffusion behavior of uranium vacancies. We show that under homogeneous strain fields, only the dipole tensor of the saddle with respect to the minimum is required to correctly predict the change in the energy barrier between the strained and the unstrained case. Diffusivities are computed using kinetic Monte Carlo simulations for both neutral and fully charged state of uranium single and divacancies. We calculate the effect of strain on migration barriers in the temperature range 8001800 K for both vacancy types. Homogeneous strains as small as 2% have a considerable effect on diffusivity of both single and divacancies of uranium, with the effect of strain being more pronounced for single vacancies than divacancies. In contrast, the response of a given defect to strain is less sensitive to changes in the charge state of the defect. Further, strain leads to anisotropies in the mobility of the vacancy and the degree of anisotropy is very sensitive to the nature of the applied strain field for strain of equal magnitude. Our results indicate that the influence of strain on vacancy diffusivity will be significantly greater when single vacancies dominate the defect structure, such as sintering, while the effects will be much less substantial under irradiation conditions where divacancies dominate.

  19. Impact of homogeneous strain on uranium vacancy diffusion in uranium dioxide

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

    Goyal, Anuj; Phillpot, Simon R.; Subramanian, Gopinath; Andersson, David A.; Stanek, Chris R.; Uberuaga, Blas P.

    2015-03-03

    We present a detailed mechanism of, and the effect of homogeneous strains on, the migration of uranium vacancies in UO2. Vacancy migration pathways and barriers are identified using density functional theory and the effect of uniform strain fields are accounted for using the dipole tensor approach. We report complex migration pathways and noncubic symmetry associated with the uranium vacancy in UO2 and show that these complexities need to be carefully accounted for to predict the correct diffusion behavior of uranium vacancies. We show that under homogeneous strain fields, only the dipole tensor of the saddle with respect to the minimummore » is required to correctly predict the change in the energy barrier between the strained and the unstrained case. Diffusivities are computed using kinetic Monte Carlo simulations for both neutral and fully charged state of uranium single and divacancies. We calculate the effect of strain on migration barriers in the temperature range 800–1800 K for both vacancy types. Homogeneous strains as small as 2% have a considerable effect on diffusivity of both single and divacancies of uranium, with the effect of strain being more pronounced for single vacancies than divacancies. In contrast, the response of a given defect to strain is less sensitive to changes in the charge state of the defect. Further, strain leads to anisotropies in the mobility of the vacancy and the degree of anisotropy is very sensitive to the nature of the applied strain field for strain of equal magnitude. Our results indicate that the influence of strain on vacancy diffusivity will be significantly greater when single vacancies dominate the defect structure, such as sintering, while the effects will be much less substantial under irradiation conditions where divacancies dominate.« less

  20. Completed Sites Listing

    Broader source: Energy.gov [DOE]

    As of fiscal year 2012, EM (and its predecessor organization UMTRA) completed cleanup and closed 91 sites in 24 states.

  1. Formation and Growth of Stacking Fault Tetrahedra in Ni via Vacancy Aggregation Mechanism

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

    Aidhy, Dilpuneet S.; Lu, Chenyang; Jin, Ke; Bei, Hongbin; Zhang, Yanwen; Wang, Lumin; Weber, William J.

    2015-12-29

    Using molecular dynamics simulations, the formation and growth of stacking fault tetrahedra (SFT) are captured by vacancy cluster diffusion and aggregation mechanisms in Ni. The vacancytetrahedron acts as a nucleation point for SFT formation. Simulations show that perfect SFT can grow to the next size perfect SFT via a vacancy aggregation mechanism. The stopping and range of ions in matter (SRIM) calculations and transmission electron microscopy (TEM) observations reveal that SFT can form farther away from the initial cascade-event locations, indicating the operation of diffusion-based vacancy-aggregation mechanism.

  2. Spin and photophysics of carbon-antisite vacancy defect in

    Office of Scientific and Technical Information (OSTI)

    Spin and photophysics of carbon-antisite vacancy defect in 4 H silicon carbide: A potential quantum bit Not Available Temp HTML ...

  3. Effect of vacancies on the structure and properties of Ga[subscript...

    Office of Scientific and Technical Information (OSTI)

    2(Sesubscript 0.33Tesubscript 0.67)subscript 3 Citation Details In-Document Search Title: Effect of vacancies on the structure and properties of Gasubscript 2(Sesubsc...

  4. Deactivation Completion and Turnover

    Broader source: Energy.gov [DOE]

    Achieving consensus that deactivation is complete can involve several parties including the deactivation contractor, the Field Office, DOE Headquarters, the post-deactivation contractor, regulators...

  5. Vacancy-type defects induced by grinding of Si wafers studied by monoenergetic positron beams

    SciTech Connect (OSTI)

    Uedono, Akira; Yoshihara, Nakaaki; Mizushima, Yoriko; Kim, Youngsuk; Nakamura, Tomoji; Ohba, Takayuki; Oshima, Nagayasu; Suzuki, Ryoichi

    2014-10-07

    Vacancy-type defects introduced by the grinding of Czochralski-grown Si wafers were studied using monoenergetic positron beams. Measurements of Doppler broadening spectra of the annihilation radiation and the lifetime spectra of positrons showed that vacancy-type defects were introduced in the surface region (<98 nm), and the major defect species were identified as (i) relatively small vacancies incorporated in dislocations and (ii) large vacancy clusters. Annealing experiments showed that the defect concentration decreased with increasing annealing temperature in the range between 100 and 500C. After 600700C annealing, the defect-rich region expanded up to about 170 nm, which was attributed to rearrangements of dislocation networks, and a resultant emission of point defects toward the inside of the sample. Above 800C, the stability limit of those vacancies was reached and they started to disappear. After the vacancies were annealed out (900C), oxygen-related defects were the major point defects and they were located at <25 nm.

  6. NPDF status

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

    NPDF INSTRUMENT STATUS Waiting for runs .. Last update: Fri Mar 27 04:43:30 2015 NPDF RECENT DATA PLOTTING Select plot: GSAS - PDF...

  7. Edison's move has completed

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

    completed January 8, 2016 by Richard Gerber We're pleased to announce that Edison is once again available to all NERSC users. The move from the NERSC Oakland Scientific Facility...

  8. Complete Safety Training

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

    Complete Safety Training Print Facility Safety Training Required for ALL Users Users must register with the ALS to obtain an LBNL ID number before they can complete safety training courses. Once registered, choose the non-LDAP login and enter your LBNL ID number to begin. ALS 1001: Safety at the ALS EHS 0470: General Employee Radiation Training (GERT) Special Training Required for Some Users Laser Safety Users working with a Class 3B/4 laser EHS 0302 Macromolecular Crystallography Users

  9. Complete Safety Training

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

    Complete Safety Training Print Facility Safety Training Required for ALL Users Users must register with the ALS to obtain an LBNL ID number before they can complete safety training courses. Once registered, choose the non-LDAP login and enter your LBNL ID number to begin. ALS 1001: Safety at the ALS EHS 0470: General Employee Radiation Training (GERT) Special Training Required for Some Users Laser Safety Users working with a Class 3B/4 laser EHS 0302 Macromolecular Crystallography Users

  10. Complete Safety Training

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

    Complete Safety Training Print Facility Safety Training Required for ALL Users Users must register with the ALS to obtain an LBNL ID number before they can complete safety training courses. Once registered, choose the non-LDAP login and enter your LBNL ID number to begin. ALS 1001: Safety at the ALS EHS 0470: General Employee Radiation Training (GERT) Special Training Required for Some Users Laser Safety Users working with a Class 3B/4 laser EHS 0302 Macromolecular Crystallography Users

  11. Complete Safety Training

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

    Complete Safety Training Print Facility Safety Training Required for ALL Users Users must register with the ALS to obtain an LBNL ID number before they can complete safety training courses. Once registered, choose the non-LDAP login and enter your LBNL ID number to begin. ALS 1001: Safety at the ALS EHS 0470: General Employee Radiation Training (GERT) Special Training Required for Some Users Laser Safety Users working with a Class 3B/4 laser EHS 0302 Macromolecular Crystallography Users

  12. Complete Safety Training

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

    Complete Safety Training Print Facility Safety Training Required for ALL Users Users must register with the ALS to obtain an LBNL ID number before they can complete safety training courses. Once registered, choose the non-LDAP login and enter your LBNL ID number to begin. ALS 1001: Safety at the ALS EHS 0470: General Employee Radiation Training (GERT) Special Training Required for Some Users Laser Safety Users working with a Class 3B/4 laser EHS 0302 Macromolecular Crystallography Users

  13. Method for large-scale fabrication of atomic-scale structures on material surfaces using surface vacancies

    DOE Patents [OSTI]

    Lim, Chong Wee; Ohmori, Kenji; Petrov, Ivan Georgiev; Greene, Joseph E.

    2004-07-13

    A method for forming atomic-scale structures on a surface of a substrate on a large-scale includes creating a predetermined amount of surface vacancies on the surface of the substrate by removing an amount of atoms on the surface of the material corresponding to the predetermined amount of the surface vacancies. Once the surface vacancies have been created, atoms of a desired structure material are deposited on the surface of the substrate to enable the surface vacancies and the atoms of the structure material to interact. The interaction causes the atoms of the structure material to form the atomic-scale structures.

  14. Effect of cation ordering on oxygen vacancy diffusion pathways in double perovskites

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

    Uberuaga, Blas Pedro; Pilania, Ghanshyam

    2015-07-08

    Perovskite structured oxides (ABO3) are attractive for a number of technological applications, including as superionics because of the high oxygen conductivities they exhibit. Double perovskites (AA’BB’O6) provide even more flexibility for tailoring properties. Using accelerated molecular dynamics, we examine the role of cation ordering on oxygen vacancy mobility in one model double perovskite SrLaTiAlO6. We find that the mobility of the vacancy is very sensitive to the cation ordering, with a migration energy that varies from 0.6 to 2.7 eV. In the extreme cases, the mobility is both higher and lower than either of the two end member single perovskites.more » Further, the nature of oxygen vacancy diffusion, whether one-dimensional, two-dimensional, or three-dimensional, also varies with cation ordering. We correlate the dependence of oxygen mobility on cation structure to the distribution of Ti4+ cations, which provide unfavorable environments for the positively charged oxygen vacancy. The results demonstrate the potential of using tailored double perovskite structures to precisely control the behavior of oxygen vacancies in these materials.« less

  15. SMARTS status

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

    ContactsPhonebookOrganizationMapsCalendarJobs NEWS LIBRARY JOBS Search Lujan Home| Proposal Process | Ancillary Equipment | Chemical & Sample Prep | Training Office | Web Contact SMARTS INSTRUMENT STATUS Instrument Status (Last updated: 2016/03/02 14:04:07) Run Number: 97106 Title: Adams Sample 6-4 after heat treat to 1000C [abso strain -10.000 Run Status: ended Last Script Activity: 2016/02/28 20:05:52: End run 97106; mah 300000 abso strain -10.000 100.0 * * * * * * View full script Next

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    Completed Jobs Franklin Completed Jobs Select a time period Show jobs that completed after Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec 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 26 27 28 29 30 31 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 @ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 : 0 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 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46

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    Help Staff Blogs Request Repository Mailing List Need Help? Out-of-hours Status and Password help Call operations: 1-800-66-NERSC, option 1 or 510-486-6821 Account Support ...

  18. Complete Experiment Safety Documentation

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

    Complete Experiment Safety Documentation Print User Safety Overview Upon receiving beam time: 1. Log in to ALSHub to complete an Experiment Safety Sheet (ESS). The ALS This e-mail address is being protected from spambots. You need JavaScript enabled to view it is available to support you through this process. Please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it at the email link or at (510) 486-7222 at if you have questions or need more

  19. Complete Experiment Safety Documentation

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

    Complete Experiment Safety Documentation Print User Safety Overview Upon receiving beam time: 1. Log in to ALSHub to complete an Experiment Safety Sheet (ESS). The ALS This e-mail address is being protected from spambots. You need JavaScript enabled to view it is available to support you through this process. Please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it at the email link or at (510) 486-7222 at if you have questions or need more

  20. Complete Experiment Safety Documentation

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

    Complete Experiment Safety Documentation Print User Safety Overview Upon receiving beam time: 1. Log in to ALSHub to complete an Experiment Safety Sheet (ESS). The ALS This e-mail address is being protected from spambots. You need JavaScript enabled to view it is available to support you through this process. Please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it at the email link or at (510) 486-7222 at if you have questions or need more

    1. Complete Experiment Safety Documentation

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

      Complete Experiment Safety Documentation Print User Safety Overview Upon receiving beam time: 1. Log in to ALSHub to complete an Experiment Safety Sheet (ESS). The ALS This e-mail address is being protected from spambots. You need JavaScript enabled to view it is available to support you through this process. Please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it at the email link or at (510) 486-7222 at if you have questions or need more

    2. Electrical compensation by Ga vacancies in Ga{sub 2}O{sub 3} thin films

      SciTech Connect (OSTI)

      Korhonen, E.; Tuomisto, F.; Gogova, D.; Wagner, G.; Baldini, M.; Galazka, Z.; Schewski, R.; Albrecht, M.

      2015-06-15

      The authors have applied positron annihilation spectroscopy to study the vacancy defects in undoped and Si-doped Ga{sub 2}O{sub 3} thin films. The results show that Ga vacancies are formed efficiently during metal-organic vapor phase epitaxy growth of Ga{sub 2}O{sub 3} thin films. Their concentrations are high enough to fully account for the electrical compensation of Si doping. This is in clear contrast to another n-type transparent semiconducting oxide In{sub 2}O{sub 3}, where recent results show that n-type conductivity is not limited by cation vacancies but by other intrinsic defects such as O{sub i}.

    3. Pd-vacancy complex in Ge: TDPAC and ab initio study

      SciTech Connect (OSTI)

      Abiona, Adurafimihan A.; Kemp, Williams; Timmers, Heiko

      2014-02-21

      Low temperature metal-induced-crystallized germanium is a promising alternative for silicon in Complementary Metal-Oxide-Semiconductor (CMOS) technology. Palladium (Pd) is one of the metals suitable for inducing the low temperature crystallization. It is not certain, how residual Pd atoms are integrated into the Ge lattice. Therefore, time-different ?-? perturbed angular correlation (TDPAC) technique using the {sup 100}Pd(?{sup 100}Rh) nuclear probe has been applied to study the hyperfine interactions of this probe in single crystalline undoped Ge. A Pd-vacancy (Pd-V) complex with a unique interaction frequency of 8.4(2) Mrad/s has been identified. The Pd-V complex has been measured to have a maximum fraction after annealing at 350 C. Density functional theory calculations have confirmed that the Pd-V complex may have the split-vacancy configuration in Ge, in contrast to the full-vacancy configuration observed in Si.

    4. Fast nanoscale addressability of nitrogen-vacancy spins via coupling to a dynamic ferromagnetic vortex

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

      Wolf, M. S.; Badea, R.; Berezovsky, J.

      2016-06-14

      The core of a ferromagnetic vortex domain creates a strong, localized magnetic field, which can be manipulated on nanosecond timescales, providing a platform for addressing and controlling individual nitrogen-vacancy centre spins in diamond at room temperature, with nanometre-scale resolution. Here, we show that the ferromagnetic vortex can be driven into proximity with a nitrogen-vacancy defect using small applied magnetic fields, inducing significant nitrogen-vacancy spin splitting. We also find that the magnetic field gradient produced by the vortex is sufficient to address spins separated by nanometre-length scales. By applying a microwave-frequency magnetic field, we drive both the vortex and the nitrogen-vacancymore » spins, resulting in enhanced coherent rotation of the spin state. Lastly, we demonstrate that by driving the vortex on fast timescales, sequential addressing and coherent manipulation of spins is possible on ~ 100 ns timescales.« less

    5. Positron annihilation spectroscopy of vacancy-type defects hierarchy in submicrocrystalline nickel during annealing

      SciTech Connect (OSTI)

      Kuznetsov, Pavel V.; Mironov, Yuri P. E-mail: tolmach@ispms.tsc.ru Tolmachev, Aleksey I. E-mail: tolmach@ispms.tsc.ru Rakhmatulina, Tanzilya V. E-mail: tolmach@ispms.tsc.ru; Bordulev, Yuri S. E-mail: laptev.roman@gmail.com Laptev, Roman S. E-mail: laptev.roman@gmail.com Lider, Andrey M. E-mail: laptev.roman@gmail.com Mikhailov, Andrey A. E-mail: laptev.roman@gmail.com; Korznikov, Alexander V.

      2014-11-14

      Positron annihilation and X-ray diffraction analysis have been used to study submicrocrystalline nickel samples prepared by equal channel angular pressing. In the as-prepared samples the positrons are trapped at dislocation-type defects and in vacancy clusters that can include up to 5 vacancies. The study has revealed that the main positron trap centers at the annealing temperature of ΔT= 20°C-180°C are low-angle boundaries enriched by impurities. At ΔT = 180°C-360°C, the trap centers are low-angle boundaries providing the grain growth due to recrystallization in-situ.

    6. Complete Experiment Safety Documentation

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

      Complaint Form Complaint Form The Office of Inspector General (OIG) maintains a Hotline to facilitate the reporting of allegations of fraud, waste, abuse, or mismanagement in U.S. Department of Energy (DOE) programs or operations. To submit an allegation to the OIG, complete the form below. Acknowledgement * I acknowledge that I have read the Office of Inspector General Hotline section of the OIG website regarding issues which should be reported to the OIG, complaint processing, anonymity and

    7. Donor-vacancy pairs in irradiated n-Ge: A searching look at the problem

      SciTech Connect (OSTI)

      Emtsev, Vadim; Oganesyan, Gagik

      2014-02-21

      The present situation concerning the identification of vacancy-donor pairs in irradiated n-Ge is discussed. The challenging points are the energy states of these defects deduced from DLTS spectra. Hall effect data seem to be at variance with some important conclusions drawn from DLTS measurements. Critical points of the radiation-produced defect modeling in n-Ge are highlighted.

    8. Vacancy structures and melting behavior in rock-salt GeSbTe

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

      Zhang, Bin; Wang, Xue -Peng; Shen, Zhen -Ju; Li, Xian -Bin; Wang, Chuan -Shou; Chen, Yong -Jin; Li, Ji -Xue; Zhang, Jin -Xing; Zhang, Ze; Zhang, Sheng -Bai; et al

      2016-05-03

      Ge-Sb-Te alloys have been widely used in optical/electrical memory storage. Because of the extremely fast crystalline-amorphous transition, they are also expected to play a vital role in next generation nonvolatile microelectronic memory devices. However, the distribution and structural properties of vacancies have been one of the key issues in determining the speed of melting (or amorphization), phase-stability, and heat-dissipation of rock-salt GeSbTe, which is crucial for its technological breakthrough in memory devices. Using spherical aberration-aberration corrected scanning transmission electron microscopy and atomic scale energy-dispersive X-ray mapping, we observe a new rock-salt structure with high-degree vacancy ordering (or layered-like ordering) atmore » an elevated temperature, which is a result of phase transition from the rock-salt phase with randomly distributed vacancies. First-principles calculations reveal that the phase transition is an energetically favored process. Furthermore, molecular dynamics studies suggest that the melting of the cubic rock-salt phases is initiated at the vacancies, which propagate to nearby regions. The observation of multi-rock-salt phases suggests another route for multi-level data storage using GeSbTe.« less

    9. Cation and Vacancy Disorder in U1-yNdyO2.00-X Alloys

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

      Barabash, Rozaliya I.; Voit, Stewart L.; Aidhy, Dilpuneet S.; Lee, Seung Min; Knight, Travis W.; Sprouster, David J.; Ecker, Lynne E.

      2015-09-14

      In this study, the intermixing and clustering of U/Nd, O, and vacancies were studied by both laboratory and synchrotron-based x-ray diffraction in U1-yNdyO2-X alloys. It was found that an increased holding time at the high experimental temperature during initial alloy preparation results in a lower disorder of the Nd distribution in the alloys. Adjustment of the oxygen concentration in the U1-yNdyO2-X alloys with different Nd concentrations was accompanied by the formation of vacancies on the oxygen sublattice and a nanocrystalline component. The lattice parameters in the U1-yNdyO2-X alloys were also found to deviate significantly from Vegard's law when the Ndmore » concentration was high (53%) and decreased with increasing oxygen concentration. Such changes indicate the formation of large vacancy concentrations during oxygen adjustment at these high temperatures. Finally, the change in the vacancy concentration after the oxygen adjustment was estimated relative to Nd concentration and oxygen stoichiometry.« less

    10. Segregation and Migration of the Oxygen Vacancies in the 3 (111) Tilt Grain Boundaries of Ceria

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

      Yuan, Fenglin; Liu, Bin; Zhang, Yanwen; Weber, William J.

      2016-03-01

      In nanocrystalline materials, defect-grain boundary (GB) interaction plays a key role in determining the structure stability, as well as size-dependent ionic, electronic, magnetic and chemical properties. In this study, we systematically investigated using density functional theory segregation and migration of oxygen vacancies at the Σ3 [110] / (111) grain boundary of ceria. Three oxygen layers near the GB are predicted to be segregation sites for oxygen vacancies. Moreover, the presence of oxygen vacancies stabilizes this tilt GB at a low Fermi level and/or oxygen poor conditions. An atomic strain model was proposed to rationalize layer dependency of the relaxation energymore » for +2 charged oxygen vacancy. The structural origin of large relaxation energies at layers 1 and 2 was determined to be free-volume space that induces ion relaxation towards the GB. Our results not only pave the way for improving the oxygen transport near GBs of ceria, but also provide important insights into engineering the GB structure for better ionic, magnetic and chemical properties of nanocrystalline ceria.« less

    11. Interlayer coupling enhancement in graphene/hexagonal boron nitride heterostructures by intercalated defects or vacancies

      SciTech Connect (OSTI)

      Park, Sohee [Department of Materials Science and Engineering, Seoul National University, Seoul 151-747 (Korea, Republic of)] [Department of Materials Science and Engineering, Seoul National University, Seoul 151-747 (Korea, Republic of); Park, Changwon [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Kim, Gunn, E-mail: gunnkim@sejong.ac.kr [Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747 (Korea, Republic of)] [Department of Physics and Graphene Research Institute, Sejong University, Seoul 143-747 (Korea, Republic of)

      2014-04-07

      Hexagonal boron nitride (hBN), a remarkable material with a two-dimensional atomic crystal structure, has the potential to fabricate heterostructures with unusual properties. We perform first-principles calculations to determine whether intercalated metal atoms and vacancies can mediate interfacial coupling and influence the structural and electronic properties of the graphene/hBN heterostructure. Metal impurity atoms (Li, K, Cr, Mn, Co, and Cu), acting as extrinsic defects between the graphene and hBN sheets, produce n-doped graphene. We also consider intrinsic vacancy defects and find that a boron monovacancy in hBN acts as a magnetic dopant for graphene, whereas a nitrogen monovacancy in hBN serves as a nonmagnetic dopant for graphene. In contrast, the smallest triangular vacancy defects in hBN are unlikely to result in significant changes in the electronic transport of graphene. Our findings reveal that a hBN layer with some vacancies or metal impurities enhances the interlayer coupling in the graphene/hBN heterostructure with respect to charge doping and electron scattering.

    12. Completion and workover fluid

      SciTech Connect (OSTI)

      Block, J.

      1985-09-17

      An aqueous completion or workover fluid for oil or gas wells having at least two solid components. One component is a hydroxy containing aluminum compound represented by the formula AlO(OH).xH/sub 2/O. The second component is a fluid loss control agent which can be either a cross-linked polyvinyl alcohol or a cross-linked hydroxyalkyl cellulose reaction product. An acid soluble weighting agent can be added for wells having higher down hole pressures. Examples of the weighting agents include iron carbonates, iron oxides, calcium carbonates, dolomite, sodium or calcium chloride, zinc bromide and calcium bromide. After use, the fluid can be displaced from the well with acid, e.g. 15% HCl, and the cake previously deposited on the bore-hole wall is dissolved by the acid so that no damaging residue remains.

    13. Method of well completion

      SciTech Connect (OSTI)

      Brieger, E. F.; Colle Jr., E. A.; George, F. R.

      1985-02-12

      A perforating gun is suspended downhole in a cased borehole, in underlying relationship relative to a packer device, and adjacent to a hydrocarbon-bearing formation to be completed. A connecting tubing interconnects the gun with the packer device, and includes a rupture barrier therebetween which prevents debris from accumulating within a gun firing head. An upper tubing string is removably connected to the packer device and forms a passageway which extends from the surface of the earth, down through the packer, and to the gun firing head. The upper tubing string includes a seal means and an extension tube which sealingly engages the packer device and penetrates the rupture barrier to provide a passageway through which the gun can be fired from the surface of the earth. This combination of elements prevents malfunction of the gun when the tool is left downhole for an appreciable length of time.

    14. First-principles study of band gap engineering via oxygen vacancy doping in perovskite ABB'O₃ solid solutions

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

      Qi, Tingting; Curnan, Matthew T.; Kim, Seungchul; Bennett, Joseph W.; Grinberg, Ilya; Rappe, Andrew M.

      2011-12-15

      Oxygen vacancies in perovskite oxide solid solutions are fundamentally interesting and technologically important. However, experimental characterization of the vacancy locations and their impact on electronic structure is challenging. We have carried out first-principles calculations on two Zr-modified solid solutions, Pb(Zn1/3Nb2/3)O₃ and Pb(Mg1/3Nb2/3)O₃, in which vacancies are present. We find that the vacancies are more likely to reside between low-valent cation-cation pairs than high-valent cation-cation pairs. Based on the analysis of our results, we formulate guidelines that can be used to predict the location of oxygen vacancies in perovskite solid solutions. Our results show that vacancies can have a significant impactmore » on both the conduction and valence band energies, in some cases lowering the band gap by ≈0.5 eV. The effects of vacancies on the electronic band structure can be understood within the framework of crystal field theory.« less

    15. Status | Department of Energy

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

      Status Status PDF icon Status More Documents & Publications DOE O 206.2 Identity, Credential, and Access Management (ICAM) ICAM Workshop Audit Report: IG-0860

    16. Status of Wheeler Reservoir

      SciTech Connect (OSTI)

      Not Available

      1990-09-01

      This is one in a series of status reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Wheeler Reservoir summarizes reservoir purposes and operation, reservoir and watershed characteristics, reservoir uses and use impairments, and water quality and aquatic biological conditions. The information presented here is from the most recent reports, publications, and original data available. If no recent data were available, historical data were summarized. If data were completely lacking, environmental professionals with special knowledge of the resource were interviewed. 12 refs., 2 figs.

    17. Monthly Status Reports | Department of Energy

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

      Monthly Status Reports Monthly Status Reports Active Project Justification Statement Project Registration Number Assignments (Active) All Active DOE Technical Standards Document Project Registration Number Assignments (Completed) The Proposed Reaffirmations and Cancellations For Additional Information Contact: Jeffrey Feit phone: 301-903-0471 e-mail: jeffrey.feit@hq.doe.gov

    18. Weekly Petroleum Status Report

      Gasoline and Diesel Fuel Update (EIA)

      Please go to the redesigned Weekly Petroleum Status Report.

    19. Effects of Stone-Wales and vacancy defects in atomic-scale friction on defective graphite

      SciTech Connect (OSTI)

      Sun, Xiao-Yu; Wu, RunNi; Xia, Re; Chu, Xi-Hua; Xu, Yuan-Jie

      2014-05-05

      Graphite is an excellent solid lubricant for surface coating, but its performance is significantly weakened by the vacancy or Stone-Wales (SW) defect. This study uses molecular dynamics simulations to explore the frictional behavior of a diamond tip sliding over a graphite which contains a single defect or stacked defects. Our results suggest that the friction on defective graphite shows a strong dependence on defect location and type. The 5-7-7-5 structure of SW defect results in an effectively negative slope of friction. For defective graphite containing a defect in the surface, adding a single vacancy in the interior layer will decrease the friction coefficients, while setting a SW defect in the interior layer may increase the friction coefficients. Our obtained results may provide useful information for understanding the atomic-scale friction properties of defective graphite.

    20. Oxygen vacancies at the surface of SrTiO{sub 3} thin films

      SciTech Connect (OSTI)

      Silva, Alexandre R.; Dalpian, Gustavo M.

      2014-01-21

      The two-dimensional electron gas (2DEG) observed at the surface of oxide thin films and at the interface between two oxides has been widely discussed, but the mechanism responsible for this behavior is still not well understood. In this work, we study the properties of the SrTiO{sub 3} (001) surface and show that defects are necessary in order to explain this 2DEG. We study the properties of oxygen vacancies at the TiO{sub 2} and SrO terminated surface, and conclude they can explain the metallic behavior experimentally observed. There is a strong tendency for these vacancies to be localized at the surface, where the formation energy is less than 2.92?eV.

    1. Lithium insertion mechanism in iron-based oxyfluorides with anionic vacancies probed by PDF analysis

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

      Dambournet, Damien; Chapman, Karena W.; Duttine, Mathieu; Borkiewicz, Olaf; Chupas, Peter J.; Groult, Henri

      2015-06-25

      The mechanism of lithium insertion that occurs in an iron oxyfluoride sample with a hexagonal–tungsten–bronze (HTB)-type structure was investigated by the pair distribution function. This study reveals that upon lithiation, the HTB framework collapses to yield disordered rutile and rock salt phases followed by a conversion reaction of the fluoride phase toward lithium fluoride and nanometer-sized metallic iron. The occurrence of anionic vacancies in the pristine framework was shown to strongly impact the electrochemical activity, that is, the reversible capacity scales with the content of anionic vacancies. Similar to FeOF-type electrodes, upon de-lithiation, a disordered rutile phase forms, showing thatmore » the anionic chemistry dictates the atomic arrangement of the re-oxidized phase. Finally, it was shown that the nanoscaling and structural rearrangement induced by the conversion reaction allow the in situ formation of new electrode materials with enhanced electrochemical properties.« less

    2. Tight-binding calculation studies of vacancy and adatom defects in graphene

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

      Zhang, Wei; Lu, Wen-Cai; Zhang, Hong-Xing; Ho, K. M.; Wang, C. Z.

      2016-02-19

      Computational studies of complex defects in graphene usually need to deal with a larger number of atoms than the current first-principles methods can handle. We show a recently developed three-center tight-binding potential for carbon is very efficient for large scale atomistic simulations and can accurately describe the structures and energies of various defects in graphene. Using the three-center tight-binding potential, we have systematically studied the stable structures and formation energies of vacancy and embedded-atom defects of various sizes up to 4 vacancies and 4 embedded atoms in graphene. In conclusion, our calculations reveal low-energy defect structures and provide a moremore » comprehensive understanding of the structures and stability of defects in graphene.« less

    3. Lithium insertion mechanism in iron-based oxyfluorides with anionic vacancies probed by PDF analysis

      SciTech Connect (OSTI)

      Dambournet, Damien; Chapman, Karena W.; Duttine, Mathieu; Borkiewicz, Olaf; Chupas, Peter J.; Groult, Henri

      2015-06-25

      The mechanism of lithium insertion that occurs in an iron oxyfluoride sample with a hexagonal–tungsten–bronze (HTB)-type structure was investigated by the pair distribution function. This study reveals that upon lithiation, the HTB framework collapses to yield disordered rutile and rock salt phases followed by a conversion reaction of the fluoride phase toward lithium fluoride and nanometer-sized metallic iron. The occurrence of anionic vacancies in the pristine framework was shown to strongly impact the electrochemical activity, that is, the reversible capacity scales with the content of anionic vacancies. Similar to FeOF-type electrodes, upon de-lithiation, a disordered rutile phase forms, showing that the anionic chemistry dictates the atomic arrangement of the re-oxidized phase. Finally, it was shown that the nanoscaling and structural rearrangement induced by the conversion reaction allow the in situ formation of new electrode materials with enhanced electrochemical properties.

    4. Tevatron status

      SciTech Connect (OSTI)

      Dugan, G.

      1989-03-01

      The Fermilab Tevatron is both the world's highest energy accelerator system and first large-scale superconducting synchrotron. Since Tevatron commissioning in July 1983, the accelerator has operated in 1984, 1985 and 1987 with extracted beams of 800 GeV for three runs of fixed target physics, and in 1987, and 1988, with proton-antiproton colliding beams at 900 /times/ 900 GeV. This paper will focus on the collider operation of the Tevatron: its present status and the outlook for its longer-term future evolution. 18 refs., 3 figs., 2 tabs.

    5. Real-time observation of dynamic process of oxygen vacancy migration in cerium oxides under electric field

      SciTech Connect (OSTI)

      Li, Xiaomin; Qi, Kuo; Sun, Muhua; Huang, Qianming; Xu, Zhi E-mail: xdbai@iphy.ac.cn; Wang, Wenlong; Bai, Xuedong E-mail: xdbai@iphy.ac.cn

      2015-11-23

      The dynamic process of oxygen vacancy migration driven by the external electric field is directly observed at atomic scale in the cerium oxides (CeO{sub 2}) thin film by in-situ transmission electron microscopy method. When a bias voltage of a proper value is applied across the CeO{sub 2} film, the oxygen vacancies are formed near the interface of CeO{sub 2}/anode, followed by their migration along the direction of the external electric field. The structural modulation occurs in the [110] zone axis due to the ordering of oxygen vacancies. The migration of oxygen vacancies results in the reversible structural transformation, i.e., releasing and storing oxygen processes in CeO{sub 2}, which is of great significance for the ionic and electronic applications of the cerium oxides materials, such as oxygen pump, gas sensor, resistive random access memory, etc.

    6. Electron trap level of hydrogen incorporated nitrogen vacancies in silicon nitride

      SciTech Connect (OSTI)

      Sonoda, Ken'ichiro Tsukuda, Eiji; Tanizawa, Motoaki; Yamaguchi, Yasuo

      2015-03-14

      Hydrogen incorporation into nitrogen vacancies in silicon nitride and its effects on electron trap level are analyzed using simulation based on density functional theory with temperature- and pressure-dependent hydrogen chemical potential. If the silicon dangling bonds around a nitrogen vacancy are well separated each other, hydrogen incorporation is energetically stable up to 900 °C, which is in agreement with the experimentally observed desorption temperature. On the other hand, if the dangling bonds strongly interact, the incorporation is energetically unfavorable even at room temperature because of steric hindrance. An electron trap level caused by a nitrogen vacancy becomes shallow by the hydrogen incorporation. An electron is trapped in a deep level created by a silicon dangling bond before hydrogen incorporation, whereas it is trapped in a shallow level created by an anti-bonding state of a silicon-silicon bond after hydrogen incorporation. The simulation results qualitatively explain the experiment, in which reduced hydrogen content in silicon nitride shows superior charge retention characteristics.

    7. Tuning Interfacial Thermal Conductance of Graphene Embedded in Soft Materials by Vacancy Defects

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

      Liu, Ying; Hu, Chongze; Huang, Jingsong; Sumpter, Bobby G; Qiao, Rui

      2015-01-01

      Nanocomposites based on graphene dispersed in matrices of soft materials are promising thermal management materials. Their effective thermal conductivity depends on both the thermal conductivity of graphene and the conductance of the thermal transport across graphene-matrix interfaces. Here we report on molecular dynamics simulations of the thermal transport across the interfaces between defected graphene and soft materials in two different modes: in the across mode, heat enters graphene from one side of its basal plane and leaves through the other side; in the non-across mode, heat enters or leaves a graphene simultaneously from both sides of its basal plane. Wemore » show that, as the density of vacancy defects in graphene increases from 0 to 8%, the conductance of the interfacial thermal transport in the across mode increases from 160.4 16 to 207.8 11 MW/m2K, while that in the non-across mode increases from 7.2 0.1 to 17.8 0.6 MW/m2K. The molecular mechanisms for these variations of thermal conductance are clarified by using the phonon density of states and structural characteristics of defected graphenes. On the basis of these results and effective medium theory, we show that it is possible to enhance the effective thermal conductivity of thermal nanocomposites by tuning the density of vacancy defects in graphene despite the fact that graphene s thermal conductivity always decreases as vacancy defects are introduced.« less

    8. Vacancy-Induced Formation and Growth of Inversion Domains in Transition-Metal Dichalcogenide Monolayer

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

      Lin, Junhao; Pantelides, Sokrates T.; Zhou, Wu

      2015-04-23

      Sixty degree grain boundaries in semiconducting transition-metal dichalcogenide (TMDC) monolayers have been shown to act as conductive channels that have profound influence on both the transport properties and exciton behavior of the monolayers. We show that annealing TMDC monolayers at high temperature induces the formation of large-scale inversion domains surrounded by such 60° grain boundaries. To study the formation mechanism of such inversion domains, we use the electron beam in a scanning transmission electron microscope to activate the dynamic process within pristine TMDC monolayers. Moreover, the electron beam acts to generate chalcogen vacancies in TMDC monolayers and provide energy formore » them to undergo structural evolution. We directly visualize the nucleation and growth of such inversion domains and their 60° grain boundaries atom-by-atom within a MoSe2 monolayer and explore their formation mechanism. Combined with density functional theory, we conclude that the nucleation of the inversion domains and migration of their 60° grain boundaries are driven by the collective evolution of Se vacancies and subsequent displacement of Mo atoms, where such a dynamical process reduces the vacancy-induced lattice shrinkage and stabilizes the system. Our results can help to understand the performance of such materials under severe conditions (e.g., high temperature).« less

    9. Doping SrTiO3 supported FeSe by excess atoms and oxygen vacancies

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

      Shanavas, Kavungal Veedu; Singh, David J.

      2015-07-24

      Photoemission studies of FeSe monolayer films on SrTiO3 substrate have shown electronic structures that deviate from pristine FeSe, consistent with heavy electron doping. With the help of first-principles calculations we studied the effect of excess Fe and Se atoms on the monolayer and oxygen vacancies in the substrate in order to understand the reported Fermi surface in this system. We find that both excess Fe and Se atoms prefer the same adsorption site above the bottom Se atoms on the monolayer. The adsorbed Fe is strongly magnetic and contributes electrons to the monolayer, while excess Se hybridizes with the monolayermore » Fe-d states and partially opens a gap just above the Fermi energy. We also find that the two-dimensional electron gas generated by the oxygen vacancies is partly transferred to the monolayer and can potentially suppress the hole pockets around the Γ point. Furthermore, both O vacancies in the SrTiO3 substrate and excess Fe over the monolayer can provide high levels of electron doping.« less

    10. Localized states induced by an oxygen vacancy in rutile TiO{sub 2}

      SciTech Connect (OSTI)

      Lin, Chungwei; Shin, Donghan; Demkov, Alexander A.

      2015-06-14

      Using density functional theory and model Hamiltonian analysis, we investigate the localized states induced by an oxygen vacancy in rutile TiO{sub 2}. We identify two classes of localized states—the hybrid and the polaron. The hybrid state is caused by the orbital overlap between three Ti atoms next to a vacancy and is mainly derived from the Ti e{sub g} orbitals. The polaron state is caused by the local lattice distortion and is mainly composed of one particular t{sub 2g} orbital from a single Ti atom. The first principles calculation shows that the polaron state is energetically favored, and the tight-binding analysis reveals the underlying connection between the bulk band structure and the orbital character of the polaron. The magnetic coupling between two nearby polaron states is found to be ferromagnetic. Using this picture, we analyze the results of recent theoretical calculations and experiments and discuss the connection to vacancies in SrTiO{sub 3}.

    11. Tuning Interfacial Thermal Conductance of Graphene Embedded in Soft Materials by Vacancy Defects

      SciTech Connect (OSTI)

      Liu, Ying; Hu, Chongze; Huang, Jingsong; Sumpter, Bobby G; Qiao, Rui

      2015-01-01

      Nanocomposites based on graphene dispersed in matrices of soft materials are promising thermal management materials. Their effective thermal conductivity depends on both the thermal conductivity of graphene and the conductance of the thermal transport across graphene-matrix interfaces. Here we report on molecular dynamics simulations of the thermal transport across the interfaces between defected graphene and soft materials in two different modes: in the across mode, heat enters graphene from one side of its basal plane and leaves through the other side; in the non-across mode, heat enters or leaves a graphene simultaneously from both sides of its basal plane. We show that, as the density of vacancy defects in graphene increases from 0 to 8%, the conductance of the interfacial thermal transport in the across mode increases from 160.4 16 to 207.8 11 MW/m2K, while that in the non-across mode increases from 7.2 0.1 to 17.8 0.6 MW/m2K. The molecular mechanisms for these variations of thermal conductance are clarified by using the phonon density of states and structural characteristics of defected graphenes. On the basis of these results and effective medium theory, we show that it is possible to enhance the effective thermal conductivity of thermal nanocomposites by tuning the density of vacancy defects in graphene despite the fact that graphene s thermal conductivity always decreases as vacancy defects are introduced.

    12. Completed Sites | Department of Energy

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

      Completed Sites Completed Sites Completed Sites The Office of Environmental Management (EM) has been or is currently responsible for cleaning up sites across the United States. These sites were associated with the legacy of the nation's nuclear weapons program and other DOE research and development activities. Many of these sites have been cleaned up and transferred to other entities or to DOE's Legacy Management (LM) Program. Completed Sites Listing

    13. Sulfur vacancies in photorefractive Sn{sub 2}P{sub 2}S{sub 6} crystals

      SciTech Connect (OSTI)

      Golden, E. M.; Giles, N. C.; Basun, S. A.; Grabar, A. A.; Stoika, I. M.; Evans, D. R.; Halliburton, L. E.

      2014-12-28

      A photoinduced electron paramagnetic resonance (EPR) spectrum in single crystals of Sn{sub 2}P{sub 2}S{sub 6} (SPS) is assigned to an electron trapped at a sulfur vacancy. These vacancies are unintentionally present in undoped SPS crystals and are expected to play an important role in the photorefractive behavior of the material. Nonparamagnetic sulfur vacancies are formed during the initial growth of the crystal. Subsequent illumination below 100 K with 442 nm laser light easily converts these vacancies to EPR-active defects. The resulting S = 1/2 spectrum shows well-resolved and nearly isotropic hyperfine interactions with two P ions and two Sn ions. Partially resolved interactions with four additional neighboring Sn ions are also observed. Principal values of the g matrix are 1.9700, 1.8946, and 1.9006, with the corresponding principal axes along the a, b, and c directions in the crystal. The isotropic parts of the two primary {sup 31}P hyperfine interactions are 19.5 and 32.6 MHz and the isotropic parts of the two primary Sn hyperfine interactions are 860 and 1320 MHz (the latter values are each an average for {sup 117}Sn and {sup 119}Sn). These hyperfine results suggest that singly ionized sulfur vacancies have a diffuse wave function in SPS crystals, and thus are shallow donors. Before illumination, sulfur vacancies are in the doubly ionized charge state because of compensation by unidentified acceptors. They then trap an electron during illumination. The EPR spectrum from the sulfur vacancy is destroyed when a crystal is heated above 120 K in the dark and reappears when the crystal is illuminated again at low temperature.

    14. LARGE BLOCK TEST STATUS REPORT

      SciTech Connect (OSTI)

      Wilder, D. G.; Blair, S. C.; Buscheck, T.; Carloson, R. C.; Lee, K.; Meike, A.; Ramirez, J. L.; Sevougian, D.

      1997-08-26

      This report is intended to serve as a status report, which essentially transmits the data that have been collected to date on the Large Block Test (LBT). The analyses of data will be performed during FY98, and then a complete report will be prepared. This status report includes introductory material that is not needed merely to transmit data but is available at this time and therefore included. As such, this status report will serve as the template for the future report, and the information is thus preserved. The United States Department of Energy (DOE) is investigatinq the suitability of Yucca Mountain (YM) as a potential site for the nation's first high-level nuclear waste repository. As shown in Fig. 1-1, the site is located about 120 km northwest of Las Vegas, Nevada, in an area of uninhabited desert.

    15. Vacancy announcements

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

      Theroretical Design Electrical Engineer (R&D Engineer 1) ISR-4Space Electronics and Signal Processing Systems Engineer (R&D Engineer 3) ISR-5Space Instrumentation...

    16. Vacancy announcements

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

      Biology And Biophysics Computational Earth Science Postdoc Computational Earth Science Synthetic Inorganic Chemistry Postdoc Inorganic Isotope and Actinide Chemistry Computing ...

    17. Vacancy announcements

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

      Postdoc LANSCE Weapons PhysicsP-27 Work Control Planner 3 Work ControlMSS-WC Induction Heating & Foundry Engineer 3 Pit Related ProductsMET-2 Sensors Development Postdoc...

    18. Vacancy announcement

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

      may also include a CI-scope polygraph examination. BENEFITS: We offer a broad array of benefits. You can review our benefits at: https:help.usajobs.govindex.phpPayandBenefits...

    19. NERSC Move to CRT Complete

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

      Move to CRT Complete NERSC Move to CRT Complete April 6, 2016 by Rebecca Hartman-Baker NERSC has completed the move of the vast majority of its resources from the Oakland Scientific Facility (OSF) location to the Computational Research and Theory (CRT) building at the main Berkeley Lab campus. The major components of the move were completed earlier in the year. In particular, Edison was moved from OSF to CRT and returned to service on January 4, 2016, and all the NERSC filesystems were migrated

    20. Remote multiple string well completion

      SciTech Connect (OSTI)

      Kirkland, K.G.

      1981-04-21

      Method and apparatus for multiple string well completions by remote operations in underwater installations, by which the tubing strings are installed independently rather than simultaneously.

    1. Completed Projects Table.xlsx

      Office of Environmental Management (EM)

      Completed Projects 2005-Present Approved Actual Soil and Water Remediation Soil and Water Remediation ANLE-0030 a 28 30 2007 2007 Yes Yes Yes Nuclear Facility Deactivation and ...

    2. WIPP Firefighters Complete Fire Training

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

      May 24, 2016 WIPP Firefighters Complete Fire Training Members of the WIPP fire department recently participated in Live Fire Training at the Permian Basin Regional Training Center ...

    3. Method for enhancement of useful luminescence from vacancy defects in refractory oxides for tunable lasers

      DOE Patents [OSTI]

      Chen, Yok

      1990-01-01

      Refractory oxide crystals suitable for use in tunable lasers and a method for preparing the same are provided. The crystals are characterized by high quantum efficiency, high thermal stability, good crystal transparency, and a high percentage of useful luminescence. The method for preparation of the crystals involves removing substantially all the hydrogen, thermochemically reducing the crystal's oxygen content to produce oxygen (anion) vacancy defects, and subsequently irradiating the crystal with electrons to inactivate trace H.sup.- ions so that an increased amount of short lived F.sup.+ luminescence is produced when the crystal is optically excited.

    4. NIF Status Update - 2014

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

      status NIF Status Update - 2014 May - Highlights of May Experiments on NIF Gigabar Equation-of-State Experiments Production of Beryllium Capsules for NIF Begins First Weekly...

    5. Status of Corrective Actions

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

      WIPP AIB Report Status of Corrective Actions Status of Corrective Actions at LANL Department of Energy Issues Accident Investigation Board (AIB) Report on February 14 Incident ...

    6. Pure-state informationally complete and 'really' complete measurements

      SciTech Connect (OSTI)

      Finkelstein, J.

      2004-11-01

      I construct a positive-operator-valued measure (POVM) which has 2d rank-1 elements and which is informationally complete for generic pure states in d dimensions, thus confirming a conjecture made by Flammia, Silberfarb, and Caves (e-print quant-ph/0404137). I show that if a rank-1 POVM is required to be informationally complete for all pure states in d dimensions, it must have at least 3d-2 elements. I also show that, in a POVM which is informationally complete for all pure states in d dimensions, for any vector there must be at least 2d-1 POVM elements which do not annihilate that vector.

    7. Tuning magnetism of monolayer MoS{sub 2} by doping vacancy and applying strain

      SciTech Connect (OSTI)

      Zheng, Huiling; Yang, Baishun; Han, Ruilin; Du, Xiaobo; Yan, Yu; Wang, Dingdi

      2014-03-31

      In view of important role of inducing and manipulating the magnetism in two-dimensional materials for the development of low-dimensional spintronic devices, the influences of strain on electronic structure and magnetic properties of commonly observed vacancies doped monolayer MoS{sub 2} are investigated using first-principles calculations. It is shown that unstrained V{sub S}, V{sub S2}, and V{sub MoS3} doped monolayer MoS{sub 2} systems are nonmagnetic, while the ground state of unstrained V{sub MoS6} doped system is magnetic and the magnetic moment is contributed mainly by six Mo atoms around V{sub MoS6}. In particular, tensile strain can induce magnetic moments in V{sub S}, V{sub S2}, and V{sub MoS3} doped monolayer MoS{sub 2} due to the breaking of Mo–Mo metallic bonds around the vacancies, while the magnetization induced by V{sub MoS6} can be effectively manipulated by equibiaxial strain due to the change of Mo–Mo metallic bonds around V{sub MoS6} under strains.

    8. Completeness for sparse potential scattering

      SciTech Connect (OSTI)

      Shen, Zhongwei

      2014-01-15

      The present paper is devoted to the scattering theory of a class of continuum Schrdinger operators with deterministic sparse potentials. We first establish the limiting absorption principle for both modified free resolvents and modified perturbed resolvents. This actually is a weak form of the classical limiting absorption principle. We then prove the existence and completeness of local wave operators, which, in particular, imply the existence of wave operators. Under additional assumptions on the sparse potential, we prove the completeness of wave operators. In the context of continuum Schrdinger operators with sparse potentials, this paper gives the first proof of the completeness of wave operators.

    9. 100 Area D4 Project Building Completion Report: December 2008 to December 2009

      SciTech Connect (OSTI)

      K.G. Finucane, J.P. Harrie

      2010-10-26

      This report documents the final status of buildings after the completion of D4 activities at the 100 Area of the U.S. Department of Energy Hanford Site from December 1, 2008, to December 31, 2009.

    10. Uranium vacancy mobility at the sigma 5 symmetric tilt grain boundary in UO2

      SciTech Connect (OSTI)

      Uberuaga, Blas P.

      2012-05-02

      An important consequence of the fissioning process occurring during burnup is the formation of fission products. These fission products alter the thermo-mechanical properties of the fuel. They also lead to macroscopic changes in the fuel structure, including the formation of bubbles that are connected to swelling of the fuel. Subsequent release of fission gases increase the pressure in the plenum and can cause changes in the properties of the fuel pin itself. It is thus imperative to understand how fission products, and fission gases in particular, behave within the fuel in order to predict the performance of the fuel under operating conditions. Fission gas redistribution within the fuel is governed by mass transport and the presence of sinks such as impurities, dislocations, and grain boundaries. Thus, to understand how the distribution of fission gases evolves in the fuel, we must understand the underlying transport mechanisms, tied to the concentrations and mobilities of defects within the material, and how these gases interact with microstructural features that might act as sinks. Both of these issues have been addressed in previous work under NEAMS. However, once a fission product has reached a sink, such as a grain boundary, its mobility may be different there than in the grain interior and predicting how, for example, bubbles nucleate within grain boundaries necessitates an understanding of how fission gases diffuse within boundaries. That is the goal of the present work. In this report, we describe atomic level simulations of uranium vacancy diffusion in the pressence of a {Sigma}5 symmetric tilt boundary in urania (UO{sub 2}). This boundary was chosen as it is the simplest of the boundaries we considered in previous work on segregation and serves as a starting point for understanding defect mobility at boundaries. We use a combination of molecular statics calculations and kinetic Monte Carlo (kMC) to determine how the mobility of uranium vacancies is

    11. Tapered fiber coupling of single photons emitted by a deterministically positioned single nitrogen vacancy center

      SciTech Connect (OSTI)

      Liebermeister, Lars Petersen, Fabian; Münchow, Asmus v.; Burchardt, Daniel; Hermelbracht, Juliane; Tashima, Toshiyuki; Schell, Andreas W.; Benson, Oliver; Meinhardt, Thomas; Krueger, Anke; Stiebeiner, Ariane; Rauschenbeutel, Arno; Weinfurter, Harald; Weber, Markus

      2014-01-20

      A diamond nano-crystal hosting a single nitrogen vacancy (NV) center is optically selected with a confocal scanning microscope and positioned deterministically onto the subwavelength-diameter waist of a tapered optical fiber (TOF) with the help of an atomic force microscope. Based on this nano-manipulation technique, we experimentally demonstrate the evanescent coupling of single fluorescence photons emitted by a single NV-center to the guided mode of the TOF. By comparing photon count rates of the fiber-guided and the free-space modes and with the help of numerical finite-difference time domain simulations, we determine a lower and upper bound for the coupling efficiency of (9.5 ± 0.6)% and (10.4 ± 0.7)%, respectively. Our results are a promising starting point for future integration of single photon sources into photonic quantum networks and applications in quantum information science.

    12. Stable highly conductive ZnO via reduction of Zn vacancies

      SciTech Connect (OSTI)

      Look, David C.; Droubay, Timothy C.; Chambers, Scott A.

      2012-09-04

      Growth of Ga-doped ZnO by pulsed laser deposition at 200 ?C in an ambient of Ar and H2 produces a resistivity ? of ~ 1.5 x 10-4 ?-cm, stable to 500 ?C. Annealing on Zn foil reduces ? to ~ 1.2 x 10-4 ?-cm, one of the lowest values ever reported. The key is reducing the Zn-vacancy acceptor concentration NA to 5 x 1019, only 3% of the Ga-donor concentration ND of 1.6 x 1021 cm-3, with ND and NA determined from a degenerate mobility theory. The plasmonic wavelength is 1060 nm, further bridging the gap between metals and semiconductors.

    13. Deterministic coupling of delta-doped nitrogen vacancy centers to a nanobeam photonic crystal cavity

      SciTech Connect (OSTI)

      Lee, Jonathan C.; Cui, Shanying; Zhang, Xingyu; Russell, Kasey J.; Magyar, Andrew P.; Hu, Evelyn L.; Bracher, David O.; Ohno, Kenichi; McLellan, Claire A.; Alemn, Benjamin; Bleszynski Jayich, Ania; Andrich, Paolo; Awschalom, David; Aharonovich, Igor

      2014-12-29

      The negatively charged nitrogen vacancy center (NV) in diamond has generated significant interest as a platform for quantum information processing and sensing in the solid state. For most applications, high quality optical cavities are required to enhance the NV zero-phonon line (ZPL) emission. An outstanding challenge in maximizing the degree of NV-cavity coupling is the deterministic placement of NVs within the cavity. Here, we report photonic crystal nanobeam cavities coupled to NVs incorporated by a delta-doping technique that allows nanometer-scale vertical positioning of the emitters. We demonstrate cavities with Q up to ?24?000 and mode volume V???0.47(?/n){sup 3} as well as resonant enhancement of the ZPL of an NV ensemble with Purcell factor of ?20. Our fabrication technique provides a first step towards deterministic NV-cavity coupling using spatial control of the emitters.

    14. Oxygen-vacancy-induced room-temperature magnetization in lamellar V{sub 2}O{sub 5} thin films

      SciTech Connect (OSTI)

      Cezar, A. B.; Graff, I. L. Varalda, J.; Schreiner, W. H.; Mosca, D. H.

      2014-10-28

      In this work, we study the local atomic and electronic structures as well as oxygen-vacancy-induced magnetic properties of electrodeposited V{sub 2}O{sub 5} films. Unlike stoichiometric V{sub 2}O{sub 5}, which is a diamagnetic lamellar semiconductor, our oxygen-defective V{sub 2}O{sub 5} films are ferromagnetic at room-temperature and their saturation magnetization decreases with air exposure time. X-ray absorption spectroscopy was used to monitor the aging effect on these films, revealing that freshly-made samples exhibit only local crystalline order, whereas the aged ones undoubtedly show an enhancement of crystallinity and coordination symmetry. The mean number of oxygen atoms around V tends to increase, indicating a decrease of oxygen vacancies with time. Concurrently with the decrease of oxygen vacancies, a loss of saturation magnetization is also observed. Hence, it can be concluded that the ferromagnetism of the V{sub 2}O{sub 5} films originates from a vacancy-induced mechanism, confirming the universality of this class of ferromagnetism.

    15. Well completion and servicing fluid

      SciTech Connect (OSTI)

      Grimsley, R.L.

      1990-09-25

      This patent describes a well completion servicing fluid for controlling formation pressure during completion or servicing of a well. It comprises: an aqueous solution of calcium chloride, a solid weighing agent suspended in the solution and being selected from the group consisting of zinc, zinc oxide, and mixtures thereof; and a viscosifier dissolved in the solution in an amount effective to suspend the weighing agent. The fluid has a density of greater than 15 pounds per gallon and being substantially free of bromide ions and being substantially free of solid material which is not soluble in hydrochloric acid.

    16. Completed NSTX-U. After

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

      panel (15 tons) being inserted into the new neutral beam box. New neutral beam box (40 tons) being moved into the NSTX-U test cell. Center stack encased within the vacuum boundary and lowered into the NSTX-U. Completed center stack installed in the NSTX-U. Completed NSTX-U. After Original NSTX prior to the upgrade. Before Building the first quadrant of the center stack magnet. Winding the ohmic heating coil around the center stack. National Spherical Torus Experiment - Upgrade NSTX was a

    17. Site Transition Process Upon Cleanup Completion | Department...

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

      Process Upon Cleanup Completion Site Transition Process Upon Cleanup Completion Site Transition Process Upon Cleanup Completion PDF icon Site Transition Process Upon Cleanup ...

    18. Administration Building demolition completed under budget

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

      Administration Building demolition completed under budget Administration Building demolition completed under budget Project activities started in April 2009 and was completed five...

    19. September 2012, Work Force Retention Work Group Status Overview

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

      Work Force Retention Work Group Status Overview 2 Subgroups: Pro-Force and Non-Pro-Force Pro-Force Subgroup: Accomplishments: 1. Completion of 10 CFR 1046 Protective Force ...

    20. Updates and Status

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

      Status Updates and Status Current Status: Up Carver Email Announcements Archive An archive of email announcements sent to NERSC users regarding Carver. Read More » Timeline Timeline of significant Carver events. Read More » Last edited: 2016-04-29 11:34:35

    1. Updates and Status

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

      Status Updates and Status Current Status: Up Announcements All recent NERSC announcements affecting Euclid. Read More » Email Announcements Archive An archive of email announcements sent to NERSC users regarding Euclid. Read More » Known Problems All known current problems with Euclid. Read More » Timeline Timeline of significant Euclid events. Read More » Last edited: 2016-04-29 11:34:40

    2. Geothermal Drilling and Completion Technology Development Program. Quarterly progress report, October 1980-December 1980

      SciTech Connect (OSTI)

      Kelsey, J.R.

      1981-03-01

      The progress, status, and results of ongoing Research and Development (R and D) within the Geothermal Drilling and Completion Technology Development Program are described. The program emphasizes the development of geothermal drilling hardware, drilling fluids, completion technology, and lost circulation control methods. Advanced drilling systems are also under development.

    3. The Status of Glueballs

      SciTech Connect (OSTI)

      Lindenbaum, S.J. |

      1993-04-14

      The Status of Glueballs is presented considering that most popular candidates from among the isoscalars in the J{sup PC} = 0{sup ++}, 0{sup {minus}+} and 2{sup ++} channels. It is shown that in the 0{sup ++} channel the f{sub 0}(1720) which was discovered earlier (the S*{prime}(1720)) at BNL is highly likely the same state as the SLAC {theta}(1720) now that its spin has been found to be 0 instead of the 2 claimed for a long period. In the {sup ++} channel there is likely a complex of 2-3 states {zeta}/{eta}(1280), {lambda}/{eta}(1420) and {iota}/{eta}(1520) involving at least one extra isosclar. In the 2{sup ++}, the g{sub T}(2010), g{sub T}{prime}(2300) and g{sub T}{double_prime}(2340) {phi}{phi} states found in {pi}{sup {minus}} p {yields} {phi}{phi}n (OZI forbidden glueball filter channel) strikingly, approximately, completely break the OZI suppression and comprise within the errors all the {phi}{phi} cross-section. The only viable explanation of these states in the context of QCD is that they are produced by 1-3 primary 2{sup ++} glueballs. All alternate explanations in the past 15 years have failed.

    4. China National Machinery Industry Complete Engineering Corporation...

      Open Energy Info (EERE)

      Industry Complete Engineering Corporation CMCEC Jump to: navigation, search Name: China National Machinery Industry Complete Engineering Corporation (CMCEC) Place: Beijing,...

    5. Complete EOS for PBX 9502

      SciTech Connect (OSTI)

      Menikoff, Ralph S

      2009-10-08

      PBX 9502 is an insensitive plastic-bonded explosive based on triamino-trinitrobenzene (TATB). A complete equation of state (EOS) is constructed for unreacted PBX 9502 suitable for reactive burn models, i.e., high pressure regime in which material strength is unimportant. The PBX EOS is composed of two parts: a complete EOS for TATB and a porosity model which allows for variations in the initial PBX density. The TATB EOS is based on a cold curve and a thermal model for lattice vibrations. The heat capacity, and hence thermal model, is determined by the vibrational spectrum from Raman scattering. The cold curve is calibrated to diamond anvil cell data for isothermal compression using a two-piece Keane fitting form. Hugoniot data for PBX 9502 is used as a consistency check.

    6. Subsea completion technology needs advances

      SciTech Connect (OSTI)

      Ledbetter, R.

      1995-09-18

      Subsea technology needs further advances to reduce operational costs before operators will expand the use of subsea well completions in the Gulf of Mexico. They will continue to choose surface completion-oriented systems as long as these are more economical operationally than subsea system. Designs of subsea equipment such as trees, connectors, control pods, umbilicals, and flow lines, must bring about reductions in the cost of both installation and workover compatibility. Remote operated vehicle (ROV) manipulation is one avenue that should be exploited. The bottom line is that significant cooperation between equipment manufacturers and ROV companies is needed to develop advanced ROV technology, and operators should be involved to help guide operational strategies.

    7. Complete liquefaction methods and apparatus

      SciTech Connect (OSTI)

      Turner, Terry D.; Wilding, Bruce M.

      2013-10-15

      A method and apparatus are described to provide complete gas utilization in the liquefaction operation from a source of gas without return of natural gas to the source thereof from the process and apparatus. The mass flow rate of gas input into the system and apparatus may be substantially equal to the mass flow rate of liquefied product output from the system, such as for storage or use.

    8. Subsea completions: Subsea continues strong

      SciTech Connect (OSTI)

      Mohr, H.O.

      1996-02-01

      Comparison of 1995 statistics to the previous three years indicates that the trend for applying subsea completions remains steady at about 80 installations per year. Consistent performance at this high level means industry maintains confidence in the technology. As recently as 1990, there was a low of 36 installations--the all-time high, prior to 1993, had been 66 during 1985. Another positive indicator is the number of identified future subsea completions, i.e., those in progress, or site-specific applications under consideration. This statistic also remains steady, with 1,340 at the end of 1995, and 1,341 and 1,315 at year-end 1994 and 1993. As a comparison, in 1989 and 1990, there were 1,083 and 976 identified. Petrobras is the leading user of subsea completions with 248, three times as many as Shell, the second most active operator. The ten tables of data shown list operating companies making the installations, where they are, what type, water depth, manufacturer and other descriptive features. Preceding discussions cover industry trends and development activity influencing the installations.

    9. Heuristic status polling

      DOE Patents [OSTI]

      Archer, Charles J.; Blocksome, Michael A.; Heidelberger, Philip; Kumar, Sameer; Parker, Jeffrey J.; Ratterman, Joseph D.

      2011-06-07

      Methods, compute nodes, and computer program products are provided for heuristic status polling of a component in a computing system. Embodiments include receiving, by a polling module from a requesting application, a status request requesting status of a component; determining, by the polling module, whether an activity history for the component satisfies heuristic polling criteria; polling, by the polling module, the component for status if the activity history for the component satisfies the heuristic polling criteria; and not polling, by the polling module, the component for status if the activity history for the component does not satisfy the heuristic criteria.

    10. Upgrade of CEBAF from 6 Gev To 12 Gev: Status (Journal Article...

      Office of Scientific and Technical Information (OSTI)

      Construction is over 75% complete with final completion projected for late FY13. Details of the upgrade and status of the work will be presented. Authors: Harwood, Leigh 1 + Show ...

    11. Upgrade of CEBAF from 6-GeV To 12-GeV: Status (Conference) |...

      Office of Scientific and Technical Information (OSTI)

      Construction is over 75% complete with final completion projected for late FY13. Details of the upgrade and status of the work will be presented. Authors: Harwood, Leigh H. ...

    12. Well cleanup and completion apparatus

      SciTech Connect (OSTI)

      Brieger, E.F.

      1984-03-13

      A well cleanup and completion apparatus and technique. A packer is located downhole in a borehole, and a tool string comprising a one-way vent assembly and a one-way circulating valve assembly is connected above a perforating gun. The tool string is used to run the gun downhole through the packer until the gun arrives at a location adjacent to the formation to be perforated. During this time, the packer assembly must be in a configuration which admits flow from the lower to the upper annulus. Cleaning fluid is circulated down the entire tool string to the one-way circulating valve assembly located immediately above the firing head of the gun, thereby displacing fluid from the lower annulus, and cleaning any debris from the gun firing head. The packer is next closed, the gun detonated, whereupon the formation is perforated and production fluid flows through the perforations, up the lower annulus, into the one-way vent assembly located below the packer, into the tubing, and to the surface of the ground. Accordingly, the apparatus enables the gun and the borehole annulus adjacent the gun to be cleaned, thereby assuring that the well is properly completed in a single trip into the wellbore.

    13. A neutral oxygen-vacancy center in diamond: A plausible qubit candidate and its spintronic and electronic properties

      SciTech Connect (OSTI)

      Zhang, Y. G.; Tang, Z. Zhao, X. G.; Cheng, G. D.; Tu, Y.; Cong, W. T.; Zhu, Z. Q.; Chu, J. H.; Peng, W.

      2014-08-04

      Spintronic and electronic properties of a neutral oxygen-vacancy (O-V) center, an isoelectronic defect similar to the negatively charged nitrogen-vacancy center in diamond, were studied by combining first-principles calculations and a mean-field theory for spin hyperfine interaction. It is elucidated that the neutral O-V center is stable in the p-type diamond and possesses an S = 1 triplet ground state and four spin-conserved excited states with the spin coherence times in an order of second at T = 0 K. The results indicate that the neutral O-V center is another promising candidate for spin coherent manipulation and qubit operation.

    14. Strain-induced phase and oxygen-vacancy stability in ionic interfaces from first-principles calculations

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

      Aidhy, Dilpuneet S.; Liu, Bin; Zhang, Yanwen; Weber, William J.

      2014-12-03

      Understanding interfacial chemistry is becoming crucial in materials design for heterointerfaces. Using density functional theory, we elucidate the effect of strained interfaces on phase and oxygen-vacancy stability for CeO2 | ZrO2, ThO2 | ZrO2 and CeO2 | ThO2 interfaces. The calculations show that ZrO2 transforms from cubic fluorite to the orthorhombic columbite under tensile strain providing evidence of a previous experimental speculation of an unrecognized ZrO2 phase. We also show that oxygen vacancies could be preferably stabilized on either side of the interface by manipulating strain. We predict that they are stable in tensile-strain, and unstable in compressivestrained materials.

    15. Strain-induced phase and oxygen-vacancy stability in ionic interfaces from first-principles calculations

      SciTech Connect (OSTI)

      Aidhy, Dilpuneet S; Liu, Bin; Zhang, Yanwen; Weber, William J

      2014-01-01

      Understanding interfacial chemistry is becoming crucial in materials design for heterointerfaces. Using density functional theory, we elucidate the effect of strained interfaces on phase and oxygen-vacancy stability for CeO2 | ZrO2, ThO2 | ZrO2 and CeO2 | ThO2 interfaces. The calculations show that ZrO2 transforms from cubic fluorite to the orthorhombic columbite under tensile strain providing evidence of a previous experimental speculation of an unrecognized ZrO2 phase. We also show that oxygen vacancies could be preferably stabilized on either side of the interface by manipulating strain. We predict that they are stable in tensile-strain, and unstable in compressivestrained materials.

    16. Room-temperature in situ nuclear spin hyperpolarization from optically pumped nitrogen vacancy centres in diamond

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

      King, Jonathan P.; Jeong, Keunhong; Vassiliou, Christophoros C.; Shin, Chang S.; Page, Ralph H.; Avalos, Claudia E.; Wang, Hai-Jing; Pines, Alexander

      2015-12-07

      Low detection sensitivity stemming from the weak polarization of nuclear spins is a primary limitation of magnetic resonance spectroscopy and imaging. Methods have been developed to enhance nuclear spin polarization but they typically require high magnetic fields, cryogenic temperatures or sample transfer between magnets. Here we report bulk, room-temperature hyperpolarization of 13C nuclear spins observed via high-field magnetic resonance. The technique harnesses the high optically induced spin polarization of diamond nitrogen vacancy centres at room temperature in combination with dynamic nuclear polarization. We observe bulk nuclear spin polarization of 6%, an enhancement of ~170,000 over thermal equilibrium. The signal ofmore » the hyperpolarized spins was detected in situ with a standard nuclear magnetic resonance probe without the need for sample shuttling or precise crystal orientation. In conclusion, hyperpolarization via optical pumping/dynamic nuclear polarization should function at arbitrary magnetic fields enabling orders of magnitude sensitivity enhancement for nuclear magnetic resonance of solids and liquids under ambient conditions.« less

    17. Oxidation state and interfacial effects on oxygen vacancies in tantalum pentoxide

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

      Bondi, Robert J.; Marinella, Matthew J.

      2015-02-28

      First-principles density-functional theory (DFT) calculations are used to study the atomistic structure, structural energetics, and electron density near the O monovacancy (VOn; n=0,1+,2+) in both bulk, amorphous tantalum pentoxide (a-Ta2O5) and also at vacuum and metallic Ta interfaces. We calculate multivariate vacancy formation energies to evaluate stability as a function of oxidation state, distance from interface plane, and Fermi energy. VOn of all oxidation states preferentially segregate at both Ta and vacuum interfaces, where the metallic interface exhibits global formation energy minima. In a-Ta2O5, VO0 are characterized by structural contraction and electron density localization, while VO2+ promote structural expansion andmore » are depleted of electron density. In contrast, interfacial VO0 and VO2+ show nearly indistinguishable ionic and electronic signatures indicative of a reduced VO center. Interfacial VO2+ extract electron density from metallic Ta indicating VO2+ is spontaneously reduced at the expense of the metal. This oxidation/reduction behavior suggests careful selection and processing of both oxide layer and metal electrodes for engineering memristor device operation.« less

    18. Room-temperature in situ nuclear spin hyperpolarization from optically pumped nitrogen vacancy centres in diamond

      SciTech Connect (OSTI)

      King, Jonathan P.; Jeong, Keunhong; Vassiliou, Christophoros C.; Shin, Chang S.; Page, Ralph H.; Avalos, Claudia E.; Wang, Hai-Jing; Pines, Alexander

      2015-12-07

      Low detection sensitivity stemming from the weak polarization of nuclear spins is a primary limitation of magnetic resonance spectroscopy and imaging. Methods have been developed to enhance nuclear spin polarization but they typically require high magnetic fields, cryogenic temperatures or sample transfer between magnets. Here we report bulk, room-temperature hyperpolarization of 13C nuclear spins observed via high-field magnetic resonance. The technique harnesses the high optically induced spin polarization of diamond nitrogen vacancy centres at room temperature in combination with dynamic nuclear polarization. We observe bulk nuclear spin polarization of 6%, an enhancement of ~170,000 over thermal equilibrium. The signal of the hyperpolarized spins was detected in situ with a standard nuclear magnetic resonance probe without the need for sample shuttling or precise crystal orientation. In conclusion, hyperpolarization via optical pumping/dynamic nuclear polarization should function at arbitrary magnetic fields enabling orders of magnitude sensitivity enhancement for nuclear magnetic resonance of solids and liquids under ambient conditions.

    19. Oxidation state and interfacial effects on oxygen vacancies in tantalum pentoxide

      SciTech Connect (OSTI)

      Bondi, Robert J. Marinella, Matthew J.

      2015-02-28

      First-principles density-functional theory calculations are used to study the atomistic structure, structural energetics, and electron density near the O monovacancy (V{sub O}{sup n}; n?=?0,1+,2+) in both bulk, amorphous tantalum pentoxide (a-Ta{sub 2}O{sub 5}), and also at vacuum and metallic Ta interfaces. We calculate multivariate vacancy formation energies to evaluate stability as a function of oxidation state, distance from interface plane, and Fermi energy. V{sub O}{sup n} of all oxidation states preferentially segregates at both Ta and vacuum interfaces, where the metallic interface exhibits global formation energy minima. In a-Ta{sub 2}O{sub 5}, V{sub O}{sup 0} is characterized by structural contraction and electron density localization, while V{sub O}{sup 2+} promotes structural expansion and is depleted of electron density. In contrast, interfacial V{sub O}{sup 0} and V{sub O}{sup 2+} show nearly indistinguishable ionic and electronic signatures indicative of a reduced V{sub O} center. Interfacial V{sub O}{sup 2+} extracts electron density from metallic Ta, indicating that V{sub O}{sup 2+} is spontaneously reduced at the expense of the metal. This oxidation/reduction behavior suggests careful selection and processing of both oxide layer and metal electrodes for engineering memristor device operation.

    20. Room temperature alcohol sensing by oxygen vacancy controlled TiO{sub 2} nanotube array

      SciTech Connect (OSTI)

      Hazra, A.; Dutta, K.; Bhowmik, B.; Bhattacharyya, P.; Chattopadhyay, P. P.

      2014-08-25

      Oxygen vacancy (OV) controlled TiO{sub 2} nanotubes, having diameters of 5070?nm and lengths of 200250?nm, were synthesized by electrochemical anodization in the mixed electrolyte comprising NH{sub 4}F and ethylene glycol with selective H{sub 2}O content. The structural evolution of TiO{sub 2} nanoforms has been studied by field emission scanning electron microscopy. Variation in the formation of OVs with the variation of the structure of TiO{sub 2} nanoforms has been evaluated by photoluminescence and X-ray photoelectron spectroscopy. The sensor characteristics were correlated to the variation of the amount of induced OVs in the nanotubes. The efficient room temperature sensing achieved by the control of OVs of TiO{sub 2} nanotube array has paved the way for developing fast responding alcohol sensor with corresponding response magnitude of 60.2%, 45.3%, and 36.5% towards methanol, ethanol, and 2-propanol, respectively.

    1. Room-temperature ferromagnetism of Fe-doped TiO{sub 2} nanoparticles driven by oxygen vacancy

      SciTech Connect (OSTI)

      Patel, Sandeep K.S.; Kurian, Sajith; Gajbhiye, Namdeo S.

      2013-02-15

      Graphical abstract: A series of Ti{sub 1−x}Fe{sub x}O{sub 2−δ} (x ≤ 0.03) nanoparticles (NPs) were synthesized by sol–gel route. The room temperature ferromagnetism (RTFM) has been explained in terms of vacancy induced bound magnetic polaron (BMP) model, where the Fe{sup 3+} ions ferromagnetically coupled mediated by oxygen vacancies. Display Omitted Highlights: ► The Fe-doped NPs have been synthesized by sol–gel method. ► Ferromagnetism of Fe-doped TiO{sub 2} NPs are intrinsic property. ► Room temperature ferromagnetism observed in all the Fe-doped samples. ► Variation in M{sub s} is attributed due to oxygen vacancies and defect formation. -- Abstract: A series of Ti{sub 1−x}Fe{sub x}O{sub 2−δ} (0 ≤ x ≤ 0.03) nanoparticles (NPs) were synthesized by sol–gel route. The NPs had a size distribution in the range of 15–40 nm and were identified as the anatase TiO{sub 2} by X-ray diffraction (XRD) and Raman analysis. XRD, selected area electron diffraction, Raman and Mössbauer analysis ruled out the signature of Fe-cluster or any other oxides of Fe. The redshifting of the band edge emission peak observed in UV–vis absorption studies further confirmed the doping of Fe ions in the TiO{sub 2} lattice. Raman studies show the shifting and broadening in E{sub g}(1) and E{sub g}(3) modes with Fe doping. It suggested that the activation of ferromagnetism with increasing Fe doping concentration was related to the oxygen vacancy defects. The presence of such defects was further confirmed from electron paramagnetic resonance (EPR) measurements. The observed ferromagnetism is interpreted in terms of bound magnetic polaron (BMP) model.

    2. Status Report on Paths to Closure | Department of Energy

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

      Report on Paths to Closure Status Report on Paths to Closure This status report updates EM's life cycle cost and schedule estimates for completing cleanup, which EM last provided in the 1998 Paths to Closure report. EM issued this status report to update its life-cycle cost and schedule estimates and to introduce additional analyses that offered insights into the long-term scope of the program. Status Report on Paths to Closure (395.83 KB) More Documents & Publications Evolution and History

    3. Uranium vacancy mobility at the Σ5 symmetric tilt and Σ5 twist grain boundaries in UO₂

      SciTech Connect (OSTI)

      Uberuaga, Blas Pedro; Andersson, David A.

      2015-10-01

      Ionic transport at grain boundaries in oxides dictates a number of important phenomena, from ionic conductivity to sintering to creep. For nuclear fuels, it also influences fission gas bubble nucleation and growth. Here, using a combination of atomistic calculations and object kinetic Monte Carlo (okMC) simulations, we examine the kinetic pathways associated with uranium vacancies at two model grain boundaries in UO2. The barriers for vacancy motion were calculated using the nudged elastic band method at all uranium sites at each grain boundary and were used as the basis of the okMC simulations. For both boundaries considered – a simple tilt and a simple twist boundary – the mobility of uranium vacancies is significantly higher than in the bulk. For the tilt boundary, there is clearly preferred migration along the tilt axis as opposed to in the perpendicular direction while, for the twist boundary, migration is essentially isotropic within the boundary plane. These results show that cation defect mobility in fluorite-structured materials is enhanced at certain types of grain boundaries and is dependent on the boundary structure with the tilt boundary exhibiting higher rates of migration than the twist boundary.

    4. Uranium vacancy mobility at the Σ5 symmetric tilt and Σ5 twist grain boundaries in UO₂

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

      Uberuaga, Blas Pedro; Andersson, David A.

      2015-10-01

      Ionic transport at grain boundaries in oxides dictates a number of important phenomena, from ionic conductivity to sintering to creep. For nuclear fuels, it also influences fission gas bubble nucleation and growth. Here, using a combination of atomistic calculations and object kinetic Monte Carlo (okMC) simulations, we examine the kinetic pathways associated with uranium vacancies at two model grain boundaries in UO2. The barriers for vacancy motion were calculated using the nudged elastic band method at all uranium sites at each grain boundary and were used as the basis of the okMC simulations. For both boundaries considered – a simplemore » tilt and a simple twist boundary – the mobility of uranium vacancies is significantly higher than in the bulk. For the tilt boundary, there is clearly preferred migration along the tilt axis as opposed to in the perpendicular direction while, for the twist boundary, migration is essentially isotropic within the boundary plane. These results show that cation defect mobility in fluorite-structured materials is enhanced at certain types of grain boundaries and is dependent on the boundary structure with the tilt boundary exhibiting higher rates of migration than the twist boundary.« less

    5. On the Potential for Vacancy Annihilation as a Mechanism for Conditioning in Pu-1.9 at.% Ga

      SciTech Connect (OSTI)

      Jeffries, J R; Blobaum, K M; Schwartz, A J

      2009-03-09

      The {delta} {yields} {alpha}{prime} martensitic transformation in Pu-1.9 at.% Ga occurs when the alloy is cooled below about -100 C. This transformation exhibits anomalous behavior, where the isothermal transformation proceeds atypically with double-C kinetics. Recent work has revealed that an ambient temperature isothermal hold (referred to as conditioning) prior to the transformation has different effects depending on whether transformation proceeds in the upper- or lower-C of the double-C: the amount of transformation is increased with conditioning in the upper-C, while the transformation in the lower-C seems to be engendered by conditioning. The mechanism by which conditioning affects the low-temperature {delta} {yields} {alpha}{prime} transformation is thus of great importance to understanding the transformation itself as well as the general circumstances that can affect a martensitic phase transformation. Using differential scanning calorimetry measurements, vacancy annihilation as a mechanism for the conditioning effect has been examined. While there are some characteristics of the conditioning effect that are reminiscent of vacancy annihilation, the results of these experiments suggest that vacancy annihilation is not a likely candidate description for the conditioning effect.

    6. Updates and Status

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

      Status Updates and Status Current Status: Retired on April 30, 2012 Announcements A list of key Franklin announcements and system changes. Read More » Email Announcements Archive An archive of email announcements sent to NERSC users regarding Franklin. Read More » Franklin Timeline This page records a brief timeline of significant events and user environment changes on Franklin. Read More » Last edited: 2016-04-29 11:34:24

    7. Updates and Status

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

      Status Updates and Status Current Status: Up Open Issues List of known problems, submitted bug reports and issues we are actively working on. Read More » Hopper Featured Announcements A list of key Hopper announcements and system changes. Read More » Hopper Email Announcements Archive An archive of email announcements sent to NERSC users regarding Hopper. Read More » Announcements Hopper OS upgrade and new SW set to default next Wed, Feb 27 21 February 2013, 10:29 am Hopper scheduled

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

      SciTech Connect (OSTI)

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

      2013-11-15

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

    9. Oxygen vacancy migration in disordered Gd{sub 2}(Zr{sub x}Ti{sub 1{minus}x}){sub 2}O{sub 7}

      SciTech Connect (OSTI)

      Williford, R.E.; Weber, W.J.; Devanathan, R.; Gale, J.D.

      1999-07-01

      Oxygen vacancy formation and migration energies in the pyrochlores Gd{sub 2}(Zr{sub x}Ti{sub 1{minus}x}){sub 2}O{sub 7} were computed using atomistic energy minimization methods, with particular attention to the role of cation antisite disorder. The interatomic potentials recognize oxygens in distinct crystallographic sites (polarizations) as distinct species, and permit assessment of the directional anisotropy in vacancy migration energies. Oxygen vacancy migration is determined by O{sub 48f} {minus} O{sub 48f} transitions along the shortest edges of the TiO{sub 6} octahedra, in agreement with previous results. Oxygen vacancies migrate towards disorder to reduce local stresses. In contrast to previous work, the V{sub 08a} and V{sub O8a} + I{sub O8b} Frenkel defects are favored over the V{sub O48f} and V{sub O48f} + I{sub O8b} Frenkel. The transition V{sub O8a}{minus}> V{sub O48f} is energetically favored for the ordered structure, and activates the three dimensional O{sub 48f} {minus} O{sub 48f} vacancy migration network by filling empty 9a sites with 48f oxygens. Local regions of order and moderate disorder must both be present for optimum oxygen conductivity. High disorder retards vacancy migration.

    10. First-principles investigation of the vacancy effect on the electronic properties in M{sub 2}AlC(M = V and Nb)

      SciTech Connect (OSTI)

      Kun, Liu Yuan, Qi; Ji-Zheng, Duan

      2014-10-15

      First principles calculations have been performed to study the mono-vacancy formation energies and electronic properties of M{sub 2}AlC (M = V and Nb) compound. The results show that the M mono-vacancy has a maximum formation energy. While the C mono-vacancy has a minimum formation energy, which means that the C mono-vacancy is the energetically most favorable in M{sub 2}AlC. The d-electrons of M element contribute most to the DOS of M{sub 2}AlC around the Fermi level, it implies that the conductivity of M{sub 2}AlC comes from the transition metal M. The M-C bond is stronger than the M-Al bond, which is caused by the strong hybridization energy peak between M and C atom. In addition, the M-C bond is weaken in the presence of the M or C mono-vacancy. The cell volumes are reduced when the mono-vacancy is formed. These results help us to understand the origin of the defect-related properties and phase stability of V{sub 2}AlC and Nb{sub 2}AlC under extreme environment.

    11. Nuclear proliferation status report. Status report

      SciTech Connect (OSTI)

      1992-07-01

      This report contains information concerning the nuclear proliferation status of the following countries: (1) Russia, (2) Ukraine, (3) Belarus, (4) Kazakhstan, (5) Israel, (6) India, (7) Pakistan, (8) South Africa, (9) North Korea, (10) Iraq, (11) Iran, (12) Lybia, (13) Algeria, (14) Syria, (15) Brazil, (16) Argentina, and (17) Taiwan.

    12. Origin of the Diverse Behavior of Oxygen Vacancies in ABO3 Perovskites: A Symmetry Based Analysis

      SciTech Connect (OSTI)

      Yin, W. J.; Wei, S. H.; Al-Jassim, M. M.; Yan, Y. F.

      2012-05-15

      Using band symmetry analysis and density functional theory calculations, we reveal the origin of why oxygen vacancy (V{sub O}) energy levels are shallow in some ABO{sub 3} perovskites, such as SrTiO{sub 3}, but are deep in some others, such as LaAlO{sub 3}. We show that this diverse behavior can be explained by the symmetry of the perovskite structure and the location (A or B site) of the metal atoms with low d orbital energies, such as Ti and La atoms. When the conduction band minimum (CBM) is an antibonding {Gamma}12 state, which is usually associated with the metal atom with low d orbital energies at the A site (e.g., LaAlO{sub 3}), then the V{sub O} energy levels are deep inside the gap. Otherwise, if the CBM is the nonbonding {Gamma}25{prime} state, which is usually associated with metal atoms with low d orbital energies at the B site (e.g., SrTiO{sub 3}), then the V{sub O} energy levels are shallow and often above the CBM. The V{sub O} energy level is also deep for some uncommon ABO{sub 3} perovskite materials that possess a low s orbital, or large-size cations, and an antibonding {Gamma}{sub 1} state CBM, such as ZnTiO{sub 3}. Our results, therefore, provide guidelines for designing ABO{sub 3} perovskite materials with desired functional behaviors.

    13. Complete Streets Resources | Department of Energy

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

      Complete Streets Resources Complete Streets Resources While transportation efficiency policies are often implemented under local governments, national and state programs can play supportive roles in reducing vehicle miles traveled. Find complete streets resources below. National Complete Streets Coalition. Back to Transportation

    14. Acquisition & Financial Assistance Rules Status | Department...

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

      Acquisition & Financial Assistance Rules Status Acquisition & Financial Assistance Rules Status Subscribe to Acquisition & Financial Assistance Rules Status Updates PDF icon ...

    15. Status of the Majorana Demonstrator

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

      Cuesta, C.; Abgrall, N.; Arnquist, I. J.; Avignone, III, F. T.; Barabash, A. S.; Bertrand, F. E.; Brudanin, V.; Busch, M.; Buuck, M.; Byram, D.; et al

      2015-08-06

      The Majorana Collaboration is constructing the Majorana Demonstrator, an ultra-low background, 40-kg modular high purity Ge detector array to search for neutrinoless double-beta decay in 76Ge. In view of the next generation of tonne-scale Ge-based neutrinoless double-beta decay searches that will probe the neutrino mass scale in the inverted-hierarchy region, a major goal of the Demonstrator is to demonstrate a path forward to achieving a background rate at or below 1 count/tonne/year in the 4 keV region of interest around the Q-value at 2039 keV. Lastly, the current status of the Demonstrator is discussed, as are plans for its completion.

    16. NWP Small Business Status through June 2014

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

      Small Business Status through June 2014

    17. Oil shale: Technology status report

      SciTech Connect (OSTI)

      Not Available

      1986-10-01

      This report documents the status of the US Department of Energy's (DOE) Oil Shale Program as of the end of FY 86. The report consists of (1) a status of oil shale development, (2) a description of the DOE Oil Shale Program, (3) an FY 86 oil shale research summary, and (4) a summary of FY 86 accomplishments. Discoveries were made in FY 86 about the physical and chemical properties and behavior of oil shales, process chemistry and kinetics, in situ retorting, advanced processes, and the environmental behavior and fate of wastes. The DOE Oil Shale Program shows an increasing emphasis on eastern US oil shales and in the development of advanced oil shale processing concepts. With the award to Foster Wheeler for the design of oil shale conceptual plants, the first step in the development of a systems analysis capability for the complete oil shale process has been taken. Unocal's Parachute Creek project, the only commercial oil shale plant operating in the United States, is operating at about 4000 bbl/day. The shale oil is upgraded at Parachute Creek for input to a conventional refinery. 67 refs., 21 figs., 3 tabs.

    18. RECRUITMENT OF U.S. CITIZENS FOR VACANCIES IN IAEA SAFEGUARDS.

      SciTech Connect (OSTI)

      OCCHIOGROSSO, D.; PEPPER, S.

      2006-07-16

      The International Atomic Energy Agency (IAEA) relies on its member states to assist with recruiting qualified individuals for positions within the IAEA's secretariat. It is likewise important to the U.S. government for U.S. citizens to take positions with the IAEA to contribute to its success. It is important for persons within and outside the U.S. nuclear and safeguards industries to become aware of the job opportunities available at the IAEA and to be informed of important vacancies as they arise. The International Safeguards Project Office (ISPO) at Brookhaven National Laboratory (BNL) is tasked by the U.S. government with recruiting candidates for positions within the Department of Safeguards at the IAEA and since 1998, has been actively seeking methods for improving outreach. In addition, ISPO has been working more closely with the IAEA Division of Personnel. ISPO staff members attend trade shows to distribute information about IAEA opportunities. The shows target the nuclear industry as well as shows that are unrelated to the nuclear industry. ISPO developed a web site that provides information for prospective candidates. They have worked with the IAEA to understand its recruitment processes, to make suggestions for improvements, and to understand employment benefits so they can be communicated to potential U.S. applicants. ISPO is also collaborating with a State Department working group that is focused on increasing U.S. representation within the United Nations as a whole. Most recently Secretary of State Condoleezza Rice issued a letter to all Federal Agency heads encouraging details and transfers of their employees to international organizations to the maximum extent feasible and with due regard to their manpower requirements. She urged all federal agencies to review their detail and transfer policies and practices to ensure that employment in international organizations is promoted in a positive and active manner. In addition, she wrote that it is

    19. NIF Status Update - 2014

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

      news NIF Status Update - 2014 May Gigabar Equation-of-State Experiment Reaches Record Pressures On May 29, the NIF Team fired two gigabar (Gbar)-class equation-of-state experiments...

    20. Small Business Status

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

      Teaming Arrangements on Small Business Status The Department of Energy is planning to set aside for small businesses a number of acquisitions of a very complex nature, requiring a ...

    1. Fast Global File Status

      Energy Science and Technology Software Center (OSTI)

      2013-01-01

      Fast Global File Status (FGFS) is a system software package that implimints a scalable mechanism to retrieve file information, such as its degree of distribution or replication and consistency.

    2. PDSF Login Node Status

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

      Help Staff Blogs Request Repository Mailing List Need Help? Out-of-hours Status and Password help Call operations: 1-800-66-NERSC, option 1 or 510-486-6821 Account Support ...

    3. Updates and Status

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

      Help Staff Blogs Request Repository Mailing List Need Help? Out-of-hours Status and Password help Call operations: 1-800-66-NERSC, option 1 or 510-486-6821 Account Support ...

    4. o CNMS Status Update

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

      Town Hall User Meeting (see attached slides) * Agenda: o Intro of UEC o CNMS Status Update o UEC activities o Nominations for open seat on the UEC * Activities o Monthly Telecon o...

    5. Updates and Status

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

      Updates and Status Current Status: Up Open Issues List of known problems, submitted bug reports and issues we are actively working on Read More » Timeline and Updates A list of major system changes and updates Read More » Email Announcements Archive An archive of email announcements sent to NERSC users regarding Edison Read More » Last edited: 2016-04-29 11:34:32

    6. Safety system status monitoring

      SciTech Connect (OSTI)

      Lewis, J.R.; Morgenstern, M.H.; Rideout, T.H.; Cowley, P.J.

      1984-03-01

      The Pacific Northwest Laboratory has studied the safety aspects of monitoring the preoperational status of safety systems in nuclear power plants. The goals of the study were to assess for the NRC the effectiveness of current monitoring systems and procedures, to develop near-term guidelines for reducing human errors associated with monitoring safety system status, and to recommend a regulatory position on this issue. A review of safety system status monitoring practices indicated that current systems and procedures do not adequately aid control room operators in monitoring safety system status. This is true even of some systems and procedures installed to meet existing regulatory guidelines (Regulatory Guide 1.47). In consequence, this report suggests acceptance criteria for meeting the functional requirements of an adequate system for monitoring safety system status. Also suggested are near-term guidelines that could reduce the likelihood of human errors in specific, high-priority status monitoring tasks. It is recommended that (1) Regulatory Guide 1.47 be revised to address these acceptance criteria, and (2) the revised Regulatory Guide 1.47 be applied to all plants, including those built since the issuance of the original Regulatory Guide.

    7. Theoretical investigation of thermodynamic stability and mobility of the oxygen vacancy in ThO2 –UO2 solid solutions

      SciTech Connect (OSTI)

      Liu, B.; Aidhy, D. S.; Zhang, Y.; Weber, W. J.

      2014-10-16

      The thermodynamic stability and the migration energy barriers of oxygen vacancies in ThO2 –UO2 solid solutions are investigated by density functional theory calculations. In pure ThO2, the formation energy of oxygen vacancy is 7.58 eV and 1.46 eV under O rich and O poor conditions, respectively, while its migration energy barrier is 1.97 eV. The addition of UO2 into ThO2 significantly decreases the energetics of formation and migration of the oxygen vacancy. Among the range of UO2-ThO2 solid solutions studied in this work, UO2 exhibits the lowest formation energy (5.99 eV and -0.13 eV under O rich and O poor conditions, respectively) and Th0.25U0.75O2 exhibits the lowest migration energy barrier (~ 1 eV). Moreover, by considering chemical potential, the phase diagram of oxygen vacancy as a function of both temperature and oxygen partial pressure is shown, which could help to gain experimental control over oxygen vacancy concentration.

    8. Theoretical investigation of thermodynamic stability and mobility of the oxygen vacancy in ThO2 –UO2 solid solutions

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

      Liu, B.; Aidhy, D. S.; Zhang, Y.; Weber, W. J.

      2014-10-16

      The thermodynamic stability and the migration energy barriers of oxygen vacancies in ThO2 –UO2 solid solutions are investigated by density functional theory calculations. In pure ThO2, the formation energy of oxygen vacancy is 7.58 eV and 1.46 eV under O rich and O poor conditions, respectively, while its migration energy barrier is 1.97 eV. The addition of UO2 into ThO2 significantly decreases the energetics of formation and migration of the oxygen vacancy. Among the range of UO2-ThO2 solid solutions studied in this work, UO2 exhibits the lowest formation energy (5.99 eV and -0.13 eV under O rich and O poormore » conditions, respectively) and Th0.25U0.75O2 exhibits the lowest migration energy barrier (~ 1 eV). Moreover, by considering chemical potential, the phase diagram of oxygen vacancy as a function of both temperature and oxygen partial pressure is shown, which could help to gain experimental control over oxygen vacancy concentration.« less

    9. Correlation between morphology, chemical environment, and ferromagnetism in the intrinsic-vacancy dilute magnetic semiconductor Cr-doped Ga2Se3/Si(001)

      SciTech Connect (OSTI)

      Yitamben, E.N.; Arena, D.; Lovejoy, T.C.; Pakhomov, A.B.; Heald, S.M.; Negusse, E.; Ohuchi, F.S.; Olmstead, M.A.

      2011-01-28

      Chromium-doped gallium sesquiselenide, Cr:Ga{sub 2}Se{sub 3}, is a member of a new class of dilute magnetic semiconductors exploiting intrinsic vacancies in the host material. The correlation among room-temperature ferromagnetism, surface morphology, electronic structure, chromium concentration, and local chemical and structural environments in Cr:Ga{sub 2}Se{sub 3} films grown epitaxially on silicon is investigated with magnetometry, scanning tunneling microscopy, photoemission spectroscopy, and x-ray absorption spectroscopy. Inclusion of a few percent chromium in Ga{sub 2}Se{sub 3} results in laminar, semiconducting films that are ferromagnetic at room temperature with a magnetic moment 4{micro}{sub B}/Cr. The intrinsic-vacancy structure of defected-zinc-blende {beta}-Ga{sub 2}Se{sub 3} enables Cr incorporation in a locally octahedral site without disrupting long-range order, determined by x-ray absorption spectroscopy, as well as strong overlap between Cr 3d states and the Se 4p states lining the intrinsic-vacancy rows, observed with photoemission. The highest magnetic moment per Cr is observed near the solubility limit of roughly one Cr per three vacancies. At higher Cr concentrations, islanded, metallic films result, with a magnetic moment that depends strongly on surface morphology. The effective valence is Cr{sup 3+} in laminar films, with introduction of Cr{sup 0} upon islanding. A mechanism is proposed for laminar films whereby ordered intrinsic vacancies mediate ferromagnetism.

    10. Impact of cyclic plasma treatment on oxygen vacancy defects in TiN/HfZrO/SiON/Si gate stacks

      SciTech Connect (OSTI)

      Bhuyian, Md Nasir Uddin Misra, D.; Poddar, S.; Tapily, K.; Clark, R. D.; Consiglio, S.; Wajda, C. S.; Nakamura, G.; Leusink, G. J.

      2015-05-11

      This work evaluates the defects in HfZrO as a function of Zr addition into HfO{sub 2} and when the dielectric was subjected to a slot-plane-antenna (SPA) plasma treatment in a cyclic process to form TiN/HfZrO/SiON/Si gate stacks. The defect energy levels, estimated by temperature-dependent current-voltage measurements, suggest that Zr addition in HfO{sub 2} modifies the charge state of the oxygen vacancy formation, V{sup +}. The influence of electron affinity variation of Hf and Zr ions on the charged oxygen vacancy levels seems to have contributed to the increase in defect activation energy, E{sub a}, from 0.32 eV to 0.4 eV. The cyclic SPA plasma exposure further reduces the oxygen vacancy formation because of the film densification. When the dielectric was subjected to a constant voltage stress, the charge state oxygen vacancy formation changes to V{sup 2+} and improvement was eliminated. The trap assisted tunneling behavior, as observed by the stress induced leakage current characteristics, further supports the oxygen vacancy formation model.

    11. Formation of the dopant-oxygen vacancy complexes and its influence on the photoluminescence emissions in Gd-doped HfO{sub 2}

      SciTech Connect (OSTI)

      Wang, L. G.; Tu, H. L.; Xiong, Y. H.; Du, J.; Wang, J. W.; Huang, G. J.; Xiao, W.

      2014-09-28

      Rare earth doping is widely used to improve the desired properties of high-k dielectric oxides. However, whether rare earth doping can suppress the formation of oxygen vacancies is still debated. By using the first-principles calculations with the generalized gradient approximation and more advanced hybrid functional, we have investigated the structural and electronic properties of the dopant-oxygen vacancy complexes in Gd-doped HfO{sub 2}. Our calculations indicate that the Gd dopants interacting with oxygen vacancies can substantially shift up the V{sub O} energy states towards the conduction band edge. This together with other effects, such as capturing the localized electrons at the oxygen vacancy by Gd dopants and suppressing the randomicity of oxygen vacancy formation, improves the reliability of the devices made from Gd-doped HfO{sub 2}. Based on our calculated results, we have presented an explanation for the experimentally observed decrease of the V{sub O}-related photoluminescence intensities upon Gd doping in HfO{sub 2}.

    12. Geothermal drilling and completion technology development program. Annual progress report, October 1979-September 1980

      SciTech Connect (OSTI)

      Varnado, S.G.

      1980-11-01

      The progress, status, and results of ongoing research and development (R and D) within the Geothermal Drilling and Completion Technology Development Program are described. The program emphasizes the development of geothermal drilling hardware, drilling fluids, completion technology, and lost circulation control methods. Advanced drilling systems are also under development. The goals of the program are to develop the technology required to reduce well costs by 25% by 1983 and by 50% by 1987.

    13. Geothermal drilling ad completion technology development program. Semi-annual progress report, April-September 1979

      SciTech Connect (OSTI)

      Varnado, S.G.

      1980-05-01

      The progress, status, and results of ongoing Research and Development (R and D) within the Geothermal Drilling and Completion Technology Development Program are described. The program emphasizes the development of geothermal drilling hardware, drilling fluids, and completion technology. Advanced drilling systems are also under development. The goals of the program are to develop the technology required to reduce well costs by 25% by 1982 and by 50% by 1986.

    14. Completing Salt Waste Processing Facility is an EM Priority and Key to SRS

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

      Cleanup Progress | Department of Energy Completing Salt Waste Processing Facility is an EM Priority and Key to SRS Cleanup Progress Completing Salt Waste Processing Facility is an EM Priority and Key to SRS Cleanup Progress January 14, 2016 - 12:40pm Addthis SRS employees and contractors gather to celebrate SWPF contractor Parsons' Star status, the highest recognition in the Voluntary Protection Program (VPP). DOE launched VPP in 1994 to encourage and recognize excellence in occupational

    15. Geothermal drilling and completion technology development program. Quarterly progress report, April-June 1980

      SciTech Connect (OSTI)

      Varnado, S.G.

      1980-07-01

      The progress, status, and results of ongoing research and development (R and D) within the Geothermal Drilling and Completion Technology Development Program are reported. The program emphasizes the development of geothermal drilling hardware, drilling fluids, completion technology, and lost circulation control methods. Advanced drilling systems are also under development. The goals of the program are to develop the technology required to reduce well costs by 25% by 1983 and by 50% by 1987.

    16. Successful horizontal completions require an integrated approach

      SciTech Connect (OSTI)

      Richard, B.; Smejkal, K.; Penberthy, W. Jr.

      1997-01-01

      While a perfect well completion may not exist, depleting a hydrocarbon resource at a sustained high rate--without a workover--is the ultimate goal. Unfortunately, many horizontal well completions fail to achieve this due to wellbore damage or loss of reservoir pressure. These conditions manifest themselves in reduced production rates, extended well life and reduced profitability. Standard completion techniques are not always compatible with each other for site specific well applications. The combination of two incompatible technologies or slight changes in a completion procedure may negatively impact productivity. Hence, the most successful horizontal completion results are obtained using a compatible integrated system approach--an approach that carefully combines the best completion tools and processes to deliver an undamaged well completed at the lowest possible cost. After studying the compatibilities of various drill-in fluids, screens, filter cakes and gravel packs, recommended procedures are presented for successfully completing horizontal wells.

    17. Web Operational Status Boards

      SciTech Connect (OSTI)

      2004-04-16

      Web Operational Status Boards (WebOSB)is a web-based application designed to acquire, display, and update highly dynamic status information between multiple users and jurisdictions. WebOSB is able to disseminate real-time status information?support the timely sharing of information?with constant, dynamic updates via personal computers and the Internet between emergency operations centers (EOCs), incident command centers, and to users outside the EOC who need to know the information (hospitals, shelters, schools). The WebOSB application far exceeds outdated information-sharing methods used by emergency workers: whiteboards, Word and Excel documents, or even locality-specific Web sites. WebOSB?s capabilities include the following elements: - Secure access. Multiple users can access information on WebOSB from any personal computer with Internet access and a secure ID. Privileges are use to control access and distribution of status information and to identify users who are authorized to add or edit information. - Simultaneous update. WebOSB provides options for users to add, display, and update dynamic information simultaneously at all locations involved in the emergency management effort, A single status board can be updated from multiple locations enabling shelters and hospitals to post bed availability or list decontamination capability. - On-the-fly modification. Allowing the definition of an existing status board to be modified on-the-fly can be an asset during an emergency, where information requirements can change quickly. The status board designer feature allows an administrator to quickly define, modi,, add to, and implement new status boards in minutes without needing the help of Web designers and computer programmers. - Publisher/subscriber notification. As a subscriber, each user automatically receives notification of any new information relating to specific status boards. The publisher/subscriber feature automatically notified each user of any new

    18. Web Operational Status Boards

      Energy Science and Technology Software Center (OSTI)

      2004-04-16

      Web Operational Status Boards (WebOSB)is a web-based application designed to acquire, display, and update highly dynamic status information between multiple users and jurisdictions. WebOSB is able to disseminate real-time status information—support the timely sharing of information—with constant, dynamic updates via personal computers and the Internet between emergency operations centers (EOCs), incident command centers, and to users outside the EOC who need to know the information (hospitals, shelters, schools). The WebOSB application far exceeds outdated information-sharingmore » methods used by emergency workers: whiteboards, Word and Excel documents, or even locality-specific Web sites. WebOSB’s capabilities include the following elements: - Secure access. Multiple users can access information on WebOSB from any personal computer with Internet access and a secure ID. Privileges are use to control access and distribution of status information and to identify users who are authorized to add or edit information. - Simultaneous update. WebOSB provides options for users to add, display, and update dynamic information simultaneously at all locations involved in the emergency management effort, A single status board can be updated from multiple locations enabling shelters and hospitals to post bed availability or list decontamination capability. - On-the-fly modification. Allowing the definition of an existing status board to be modified on-the-fly can be an asset during an emergency, where information requirements can change quickly. The status board designer feature allows an administrator to quickly define, modi,, add to, and implement new status boards in minutes without needing the help of Web designers and computer programmers. - Publisher/subscriber notification. As a subscriber, each user automatically receives notification of any new information relating to specific status boards. The publisher/subscriber feature automatically notified each user of any

    19. Application for Research Affiliate Associate & Student Status |

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

      Photosynthetic Antenna Research Center Research Affiliate Program / Application for Research Affiliate Associate & Student Status Application for Research Affiliate Associate & Student Status The following application is for associates and students of PARC Research Affiliates to gain official membership in PARC. Membership is open to students and associates working on PARC-related research under a PARC Research Affiliate. Interested applicants should: Complete the brief application

    20. Industry outreach a status report

      SciTech Connect (OSTI)

      Surek, D.; Sen, R.

      1995-09-01

      The Outreach Project was initiated in October 1994 with the objective of developing a multi-year plan for the U.S. Department of Energy (DOE) for targeted outreach activities for stakeholders in industry and the general public. This status report summarizes the work on industry outreach that has been completed since the inception of the project in October 1994. A three-pronged approach was taken to ascertain issues related to industry outreach. First, there was a review of on-going and past industry outreach activities at DOE and NHA. Next, a series of meetings with industry decision makers was arranged to get a better understanding of industry interests and concerns, and to discuss how DOE and industry could work collaboratively to develop hydrogen energy systems. Third, a workshop is scheduled where representatives from industry, DOE and other federal agencies can identify issues that would enhance partnering between the federal government and industry in the development of hydrogen energy systems. At this tiny, the review of on-going and past activities has been completed. Industry interviews are in progress and a majority of meetings have been held. Analysis of the information gained is in progress. The preliminary analysis of this information indicates that for appropriate near-term demonstration-type projects, the level of interest for collaboration between DOE and industry is high. The data also identifies issues industry is concerned with which impact the commercialization of hydrogen energy systems.

    1. Automation Status | Department of Energy

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

      Automation Status Automation Status Presented at the NREL Hydrogen and Fuel Cell Manufacturing R&D Workshop in Washington, DC, August 11-12, 2011. Automation Status (1.93 MB) More Documents & Publications PEM Stack Manufacturing: Industry Status 2011 NREL/DOE Hydrogen and Fuel Cell Manufacturing R&D Workshop Report Manufacturing Barriers to High Temperature PEM Commercialization

    2. Ab-initio study of hydrogen doping and oxygen vacancy at anatase TiO{sub 2} surface

      SciTech Connect (OSTI)

      Sotoudeh, M.; Mohammadizadeh, M. R.; Hashemifar, S. J.; Abbasnejad, M.

      2014-02-15

      Density functional–pseudopotential calculations were performed to study the effects of hydrogen doping and oxygen vacancy, both individually and together, on the electronic structure and stability of (001) surface of TiO{sub 2} in the anatase phase. Based on our calculations, O/Ti termination is the most stable one, and it appears that p-states of deep and surface O atoms and d-orbitals of surface Ti atoms have roles in the valence band and, the conduction band comes from the d-orbitals of deep Ti atoms. Although, no considerable change was seen during H doping, a mid-gap state appeared below the conduction band in the O vacancy configuration. In the framework of ab-initio atomistic thermodynamics, we argue that the anatase TiO{sub 2} prefers a defected O layer termination in the [001] direction. The obtained electronic structures indicate that H doping in the bulk creates the empty mid-gap state below the conduction band and hence decreases the band gap of the system. This phenomenon may explain the enhanced photocatalytic activity of the anatase TiO{sub 2} (001) surface after hydrogenation.

    3. Nanodiamond-based nanostructures for coupling nitrogen-vacancy centres to metal nanoparticles and semiconductor quantum dots

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

      Gong, Jianxiao; Steinsultz, Nat; Ouyang, Min

      2016-06-08

      The ability to control the interaction between nitrogen-vacancy centres in diamond and photonic and/or broadband plasmonic nanostructures is crucial for the development of solid-state quantum devices with optimum performance. However, existing methods typically employ top-down fabrication, which restrict scalable and feasible manipulation of nitrogen-vacancy centres. Here, we develop a general bottom-up approach to fabricate an emerging class of freestanding nanodiamond-based hybrid nanostructures with external functional units of either plasmonic nanoparticles or excitonic quantum dots. Precise control of the structural parameters ( including size, composition, coverage and spacing of the external functional units) is achieved, representing a pre-requisite for exploring themore » underlying physics. Fine tuning of the emission characteristics through structural regulation is demonstrated by performing single-particle optical studies. Lastly, this study opens a rich toolbox to tailor properties of quantum emitters, which can facilitate design guidelines for devices based on nitrogenvacancy centres that use these freestanding hybrid nanostructures as building blocks.« less

    4. Visible light stimulating dual-wavelength emission and O vacancy involved energy transfer behavior in luminescence for coaxial nanocable arrays

      SciTech Connect (OSTI)

      Yang, Lei, E-mail: nanoyang@qq.com [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Hunan Province Key Laboratory for Spray Deposition Technology and Application, Hunan University, Changsha 410082 (China); Dong, Jiazhang; Jiang, Zhongcheng [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Pan, Anlian; Zhuang, Xiujuan [Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China)

      2014-06-14

      We report a strategy to investigate O vacancy (V{sub O}) involved energy transfer and dual-wavelength yellow emission in coaxial nanocable. By electric field deposition and subsequent sol-gel template approach, ZnO:Tb/Y{sub 2}O{sub 3}:Eu coaxial nanocable arrays are synthesized. After visible light excitation, system is promoted to O vacancy charge transfer state of V{sub O}(0/+). In the following cross relaxation, energy transfer from V{sub O} to the excitation energy level of Tb{sup 3+} in ZnO:Tb core area. While in Y{sub 2}O{sub 3}:Eu shell area, energy transfer to the excitation energy level of Eu{sup 3+}. Subsequently, dual-wavelength emission is observed. By constructing nanocable with dual-wavelength emission, yellow luminescence is obtained. Adjust doping concentration of Eu{sup 3+} or Tb{sup 3+} in the range of 0.010.05, chromaticity coordinates of ZnO:Tb/Y{sub 2}O{sub 3}:Eu nanocable stably stays at yellow region in color space except ZnO:Tb{sub 0.01}/Y{sub 2}O{sub 3}:Eu{sub 0.01}. As Vo states act as media in energy transfer process in nanocablers, visible light can stimulate dual-wavelength emissions. Yellow luminescent nanocable arrays will have great applications in light-emitting diode luminescence.

    5. Oxygen vacancy induced magnetization switching in Fe{sub 3}O{sub 4} epitaxial ultrathin films on GaAs(100)

      SciTech Connect (OSTI)

      Huang, Zhaocong; Chen, Qian; Zhai, Ya E-mail: jlwang@seu.edu.cn; Wang, Jinlan E-mail: jlwang@seu.edu.cn; Xu, Yongbing; Wang, Baoping

      2015-05-04

      The magnetic and transport properties of half metallic Fe{sub 3}O{sub 4}, which are sensitive to the stoichiometry, are the key issue for applications in spintronics. An anomalous enlargement of the saturation magnetic moment is found in a relatively thick sample of epitaxial Fe{sub 3}O{sub 4} film by post-growth oxidation method. The investigation of the thickness dependence of magnetic moment suggests that the enhanced magnetism moment may come from the existence of oxygen vacancies. First-principles calculations reveal that with oxygen vacancies in Fe{sub 3}O{sub 4} crystal the spin of Fe ions in the tetrahedron site near the vacancy is much easier to switch parallel to the Fe ions in the octahedron site by temperature disturbance, supported by the temperature dependence of magnetic moment of Fe{sub 3}O{sub 4} films in experiment.

    6. Long Range Ferromagnetic Order in LaCoO3-δ epitaxial films due to the interplay of epitaxial strain and oxygen vacancy ordering

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

      Mehta, Virat; Biskup, Nevenko; Arenholz, E; Varela del Arco, Maria; Suzuki, Yuri

      2015-04-23

      We demonstrate that a combination of electronic structure modification and oxygen vacancy ordering can stabilize a long-range ferromagnetic ground state in epitaxial LaCoO3 thin films. Highest saturation magnetization values are found in the thin films in tension on SrTiO3 and (La,Sr)(Al,Ta)O3 substrates and the lowest values are found in thin films in compression on LaAlO3. Electron microscopy reveals oxygen vacancy ordering to varying degrees in all samples, although samples with the highest magnetization are the most defective. Element-specific x-ray absorption techniques reveal the presence of high spin Co2+ and Co3+ as well as low spin Co3+ in different proportions dependingmore » on the strain state. The interactions among the high spin Co ions and the oxygen vacancy superstructure are correlated with the stabilization of the long-range ferromagnetic order.« less

    7. Role of oxygen vacancies in magnetic properties of LaAlO{sub 3}/SrTiO{sub 3} interface

      SciTech Connect (OSTI)

      Mohanta, N.; Taraphder, A.

      2014-04-24

      The interface of two band-insulators SrTiO{sub 3} and LaAlO{sub 3} exhibits a highly conducting two-dimensional electron gas which shows low-temperature superconductivity, ferromagnetism and many other novel properties. Several studies reveal that the oxygen vacancies at the interface have strong influence on the electronic and magnetic properties of the interface electrons. Here, we develop an insight into the effects of oxygen vacancies on the magnetic properties of the system; the oxygen vacancies help in establishing ferromagnetism which competes with superconductivity at low temperatures. Simulated Monte-Carlo annealing suggests an ordering of the oxygen vacant sites and sheds light on the experimental observation of the quenching of magnetic moment on annealing. A possible explanation for the coexistence of superconductivity and ferromagnetism is also discussed.

    8. Direct memory access transfer completion notification

      DOE Patents [OSTI]

      Archer, Charles J. , Blocksome; Michael A. , Parker; Jeffrey J.

      2011-02-15

      Methods, systems, and products are disclosed for DMA transfer completion notification that include: inserting, by an origin DMA on an origin node in an origin injection FIFO, a data descriptor for an application message; inserting, by the origin DMA, a reflection descriptor in the origin injection FIFO, the reflection descriptor specifying a remote get operation for injecting a completion notification descriptor in a reflection injection FIFO on a reflection node; transferring, by the origin DMA to a target node, the message in dependence upon the data descriptor; in response to completing the message transfer, transferring, by the origin DMA to the reflection node, the completion notification descriptor in dependence upon the reflection descriptor; receiving, by the origin DMA from the reflection node, a completion packet; and notifying, by the origin DMA in response to receiving the completion packet, the origin node's processing core that the message transfer is complete.

    9. Direct memory access transfer completion notification

      DOE Patents [OSTI]

      Archer, Charles J.; Blocksome, Michael A.; Parker, Jeffrey J.

      2011-02-15

      DMA transfer completion notification includes: inserting, by an origin DMA engine on an origin node in an injection first-in-first-out (`FIFO`) buffer, a data descriptor for an application message to be transferred to a target node on behalf of an application on the origin node; inserting, by the origin DMA engine, a completion notification descriptor in the injection FIFO buffer after the data descriptor for the message, the completion notification descriptor specifying a packet header for a completion notification packet; transferring, by the origin DMA engine to the target node, the message in dependence upon the data descriptor; sending, by the origin DMA engine, the completion notification packet to a local reception FIFO buffer using a local memory FIFO transfer operation; and notifying, by the origin DMA engine, the application that transfer of the message is complete in response to receiving the completion notification packet in the local reception FIFO buffer.

    10. Subsea completions set for growth, standardization

      SciTech Connect (OSTI)

      Baugh, B.F.

      1988-08-22

      There have been enough subsea completion systems installed to permit categorization of some basic combinations and to permit users to choose from alternative styles. Nevertheless, advances in engineering standards, increasing capabilities, and a growing market will continue to make this an exciting area during the next 10 to 20 years. Fundamentally, subsea completion systems provide the same capabilities as surface completion and injection wells. However, they are of course more complex to accommodate special needs associated with subsea and remote operations. As of the end of 1987, there had been 472 subsea completions installed. A total of 671 future subsea completions have been identified. These completions have been characterized by differences in styles, applications, manufacturer designs, and user preferences. Subsea completions are characterized by many alternatives for construction and operation. As a result, they cannot be simply categorized by as few styles. Identifying these basic combinations gives the reader the capability to envision the alternatives which might suit his or her particular needs.

    11. PCMDI software system: status and future plans report no. 44

      SciTech Connect (OSTI)

      Williams, Dean N.

      1997-08-01

      This report describes the current status and future plans of PCMDI`s software products. A complete description of each product is provided, including the product`s problem statement, purpose, requirements, design diagram, current status, future development, developers, contributors, and off-site collaborators. While it is noted that each software product can be executed as an independent process, it is important to discern that all products work together in the complete PCMDI Software Systems: A suite of software tools facilitating for the storage, diagnosis, and visualization of climate data.

    12. Status of Acquisition Letters

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

      Workers under Service Contracts Jason Taylor Active until rulemaking is complete 6 ... Management and Operating Contracts Jason Taylor Superseded by coverage in the Acquisition ...

    13. FRIB Cryogenic Plant Status

      SciTech Connect (OSTI)

      Dixon, Kelly D.; Ganni, Venkatarao; Knudsen, Peter N.; Casagranda, Fabio

      2015-12-01

      After practical changes were approved to the initial conceptual design of the cryogenic system for MSU FRIB and an agreement was made with JLab in 2012 to lead the design effort of the cryogenic plant, many activities are in place leading toward a cool-down of the linacs prior to 2018. This is mostly due to using similar equipment used at CHLII for the 12 GeV upgrade at JLab and an aggressive schedule maintained by the MSU Conventional Facilities department. Reported here is an updated status of the cryogenic plant, including the equipment procurement status, plant layout, facility equipment and project schedule.

    14. Direct memory access transfer completion notification

      DOE Patents [OSTI]

      Archer, Charles J.; Blocksome, Michael A.; Parker, Jeffrey J.

      2010-08-17

      Methods, apparatus, and products are disclosed for DMA transfer completion notification that include: inserting, by an origin DMA engine on an origin compute node in an injection FIFO buffer, a data descriptor for an application message to be transferred to a target compute node on behalf of an application on the origin compute node; inserting, by the origin DMA engine, a completion notification descriptor in the injection FIFO buffer after the data descriptor for the message, the completion notification descriptor specifying an address of a completion notification field in application storage for the application; transferring, by the origin DMA engine to the target compute node, the message in dependence upon the data descriptor; and notifying, by the origin DMA engine, the application that the transfer of the message is complete, including performing a local direct put operation to store predesignated notification data at the address of the completion notification field.

    15. Princeton Plasma Physics Laboratory achieves milestone, completing...

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

      Princeton Plasma Physics Laboratory achieves milestone, completing first part of heart of ... Engineers and technicians at the U.S. Department of Energy's Princeton Plasma Physics ...

    16. Hanford Site Cleanup Completion Framework - Hanford Site

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

      Plan Single-Shell Tank Evaluations Deep Vadose Zone 100-F RIFS Sitewide Probabilistic Seismic Hazard Analysis Environmental Hanford Site Cleanup Completion Framework Email Email...

    17. Geothermal Well Completion Tests | Open Energy Information

      Open Energy Info (EERE)

      and immediately after drilling activities are completed. Author Hagen Hole Conference Petroleum Engineering Summer School; Dubrovnik, Croatia; 20080609 Published NA, 2008 DOI...

    18. Complete information acquisition in scanning probe microscopy...

      Office of Scientific and Technical Information (OSTI)

      Citation Details In-Document Search Title: Complete ... Here, we report a fundamentally new approach for SPM imaging ... Type: Accepted Manuscript Journal Name: Nature ...

    19. JOBAID-LAUNCHING AND COMPLETING ASSIGNED SURVEY

      Broader source: Energy.gov [DOE]

      The purpose of this job aid is to guide users through the step-by-step process of launching and completing assigned surverys.

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

      Office of Scientific and Technical Information (OSTI)

      Journal Article: Specificity and completion time distributions of ... Using the Laplace transform of the corresponding chemical master equation, we obtain an analytical solution for the ...

    1. Floating Oscillating Water Column Reference Model Completed

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

      Floating Oscillating Water Column Reference Model Completed - Sandia Energy Energy Search ... Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 ...

    2. Environmental Remediation program completes legacy mercury cleanup...

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

      Stories Legacy slope-side cleanup Environmental Remediation program completes legacy mercury cleanup near Smith's Marketplace Los Alamos National Laboratory performed a ...

    3. Glueballs: a status report

      SciTech Connect (OSTI)

      Scharre, D.L.

      1982-01-01

      It is expected from quantum chromodynamics (QCD) that glueballs, bound states which contain gluons but no valence quarks, should exist. To date, no conclusive evidence for glueballs has been presented. After a brief review of the expected properties and experimental signatures of glueballs the status of some glueball candidate states are discussed.

    4. Completion practices in deep sour Tuscaloosa wells

      SciTech Connect (OSTI)

      Huntoon, G.G.

      1984-01-01

      Successful development of the Tuscaloosa trend in Louisiana has required unique completion practices to produce the trend's deep sour formations. Amoco's operations in the Tuscaloosa formation are between 16,000 and 21,000 ft (4877 and 6400 m), and a range of pressure environments, high temperatures, and corrosive elements is encountered. Application of proved completion practices and equipment has resulted in several techniques that enhance the safety, longevity, and production capacity of these wells. The design of deep Tuscaloosa completions is assisted by a series of correlations developed to project bottomhole and surface shut-in tubing pressures, temperature gradients, and flow capacities for deep sour wells. This paper discusses material selection, completion practices, completion fluids, wellhead equipment, packer designs, corrosion-inhibition systems, and safety and monitoring equipment used in the Tuscaloosa trend. The design of a wellhead surface installation used to detect equipment failure, to pump kill fluids, and to circulate corrosion inhibitors is reviewed. A case study illustrates the methods used in completing a Tuscaloosa well with surface pressures exceeding 16,000 psi (110.3 MPa). Deep high-pressure sour-gas wells can be completed safely if all the elements of the environment that will affect the mechanical integrity of the wellbore are considered in the completion designs. The development of higher-strength material capable of withstanding SSC is needed if wells are completed in formations deeper than 22,000 ft (6700 m). Further research is necessary on the use of alloy steels and nonferrous metals for sour service. Effective high-temperature corrosion inhibitors for heavy zinc bromide completion fluids must be developed before these brines can be used in the Tuscaloosa. The testing of new inhibitors for use in highpressure sour-gas completions should be continued.

    5. Department of Energy Completes Demolition of K-33 Building -...

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

      Completes Demolition of K-33 Building - Largest Completed Demo Project in Oak Ridge History Department of Energy Completes Demolition of K-33 Building - Largest Completed Demo Project ...

    6. Electronic and crystal structure changes induced by in-plane oxygen vacancies in multiferroic YMnO3

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

      Cheng, Shaobo; Meng, Qingping; Li, Mengli; Duan, Wenhui; Zhao, Y. G.; Sun, X. F.; Zhu, Yimei; Zhu, Jing

      2016-02-08

      Here, the widely spread oxygen vacancies (VO) in multiferroic materials can strongly affect their physical properties. However, their exact influence has rarely been identified in hexagonal manganites. Here, with the combined use of transmission electron microscopy (TEM) and first-principles calculations, we have systematically studied the electronic and crystal structure modifications induced by VO located at the same Mn atomic plane (in-plane VO). Our TEM experiments reveal that the easily formed in-plane VO not only influence the electronic structure of YMnO3 but alter the in-plane Wyckoff positions of Mn ions, which may subsequently affect the intraplane and interplane exchange interaction ofmore » Mn ions. The ferroelectricity is also impaired due to the introduction of VO. Further calculations confirm these electronic and structural changes and modifications. Our results indicate that the electronic and crystal structure of YMnO3 can be manipulated by the creation of VO.« less

    7. Simulation of xenon, uranium vacancy and interstitial diffusion and grain boundary segregation in UO2

      SciTech Connect (OSTI)

      Andersson, Anders D.; Tonks, Michael R.; Casillas, Luis; Nerikar, Pankaj; Vyas, Shyam; Uberuaga, Blas P.; Stanek, Christopher R.

      2014-10-31

      In light water reactor fuel, gaseous fission products segregate to grain boundaries, resulting in the nucleation and growth of large intergranular fission gas bubbles. Based on the mechanisms established from density functional theory (DFT) and empirical potential calculations 1, continuum models for diffusion of xenon (Xe), uranium (U) vacancies and U interstitials in UO2 have been derived for both intrinsic conditions and under irradiation. Segregation of Xe to grain boundaries is described by combining the bulk diffusion model with a model for the interaction between Xe atoms and three different grain boundaries in UO2 ( Σ5 tilt, Σ5 twist and a high angle random boundary),as derived from atomistic calculations. All models are implemented in the MARMOT phase field code, which is used to calculate effective Xe and U diffusivities as well as redistribution for a few simple microstructures.

    8. Completion processing for data communications instructions

      DOE Patents [OSTI]

      Blocksome, Michael A.; Kumar, Sameer; Parker, Jeffrey J.

      2014-07-01

      Completion processing of data communications instructions in a distributed computing environment with computers coupled for data communications through communications adapters and an active messaging interface (`AMI`), injecting for data communications instructions into slots in an injection FIFO buffer a transfer descriptor, at least some of the instructions specifying callback functions; injecting a completion descriptor for each instruction that specifies a callback function into an injection FIFO buffer slot having a corresponding slot in a pending callback list; listing in the pending callback list callback functions specified by data communications instructions; processing each descriptor in the injection FIFO buffer, setting a bit in a completion bit mask corresponding to the slot in the FIFO where the completion descriptor was injected; and calling by the AMI any callback functions in the pending callback list as indicated by set bits in the completion bit mask.

    9. Completion processing for data communications instructions

      DOE Patents [OSTI]

      Blocksome, Michael A.; Kumar, Sameer; Jeffrey, Parker J.

      2014-06-10

      Completion processing of data communications instructions in a distributed computing environment with computers coupled for data communications through communications adapters and an active messaging interface (`AMI`), injecting for data communications instructions into slots in an injection FIFO buffer a transfer descriptor, at least some of the instructions specifying callback functions; injecting a completion descriptor for each instruction that specifies a callback function into an injection FIFO buffer slot having a corresponding slot in a pending callback list; listing in the pending callback list callback functions specified by data communications instructions; processing each descriptor in the injection FIFO buffer, setting a bit in a completion bit mask corresponding to the slot in the FIFO where the completion descriptor was injected; and calling by the AMI any callback functions in the pending callback list as indicated by set bits in the completion bit mask.

    10. Roles of Vacancy/Interstitial Diffusion and Segregation in the Microchemistry at Grain Boundaries of Irradiated Fe-Cr-Ni alloys

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

      Yang, Ying; Field, Kevin G.; Allen, Todd R.; Busby, Jeremy T.

      2016-02-23

      A detailed analysis of the diffusion fluxes near and at grain boundaries of irradiated Fe–Cr–Ni alloys, induced by preferential atom-vacancy and atom-interstitial coupling, is presented. The diffusion flux equations were based on the Perks model formulated through the linear theory of the thermodynamics of irreversible processes. The preferential atom-vacancy coupling was described by the mobility model, whereas the preferential atom-interstitial coupling was described by the interstitial binding model. The composition dependence of the thermodynamic factor was modeled using the CALPHAD approach. The calculated fluxes up to 10 dpa suggested the dominant diffusion mechanism for chromium and iron is via vacancy,more » while that for nickel can swing from the vacancy to the interstitial dominant mechanism. The diffusion flux in the vicinity of a grain boundary was found to be greatly modified by the segregation induced by irradiation, leading to the oscillatory behavior of alloy compositions in this region.« less