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Sample records for upward bound math

  1. College Bound American Indian Math and Science Enrichment Program (AIMS). Final report

    SciTech Connect (OSTI)

    1998-09-01

    Southwestern Indian Polytechnic Institute (SIPI), was founded in 1971 and is located on 164 acres in northwest Albuquerque, New Mexico in the center of New Mexico`s agricultural and high-tech corridors. SIPI became accredited as a community college in 1993, serves Native Americans nationwide, and is governed by a nationally-tribally appointed Board of Regents (Jicarilla Apache, Joint Oklahoma Tribes, Mescalero Apache, Navajo Nation-Arizona, Navajo Nation-New Mexico, Ten Southern Pueblos, and Eight Northern Pueblos, Southern Ute, Inter-tribal Council of Arizona, and Oglala Sioux). In 1993, The US Department of Education, TRIO Programs no longer funded the Southwestern Indian Polytechnic Institute (SIPI) Summer Math and Science Enrichment Program. However, with US Department of Energy funding SIPI was able to continue service to the Native American community under the new title of College Bound American Indian Math and Science (AIMS) Enrichment Program. This new program continued the goals and objectives of the TRIO program with an expanded focus that included students from more Native American communities nationwide. The program also interfaced with a teacher enrichment program (Rural American Indian Science Education-RAISE) sponsored by the Bureau of Indian Affairs and Sandia National Labs (SNL). SIPI in collaboration with Sandia National Laboratories and Lawrence Livermore National (LLNL) Laboratory established a mathematics and science enrichment program at SIPI for students attending rural high schools serving predominantly Native American populations. The primary goal of the program was to provide 9th--12th grade students, mostly Native American, the skills and knowledge, interest and motivation, and strategies to remain in high school and pursue a college education in a math, science, or technology based field. Each year, the program included a six-week intensive residential summer program located at SIPI as well as academic year support activities at the

  2. Help:Math | Open Energy Information

    Open Energy Info (EERE)

    math> x21+y Subscript <math>CO2<math> CO2 Subscript Grouping <math>ai,j> ai,j Fraction <math>1over2<math> <math>fracxyz> 1over2...

  3. Math Library Performance

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

    Math Library Performance Math Library Performance Fully optimizing a given application's performance often requires a deep understanding of the source, an accurate profile for a ...

  4. Applied & Computational Math

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

    & Computational Math - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us ... Twitter Google + Vimeo GovDelivery SlideShare Applied & Computational Math HomeEnergy ...

  5. Math Kernel Library (MKL)

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

    Kernel Library (MKL) Math Kernel Library (MKL) Description The Intel Math Kernel Library (Intel MKL) contains highly optimized, extensively threaded math routines for science, engineering, and financial applications. Core math functions include BLAS, LAPACK, ScaLAPACK, Sparse Solvers, Fast Fourier Transforms, Vector Math, and more. MKL is available on NERSC computer platforms where the Intel compilers are available. For instances, on Cori and Edison. If you use intel compilers to compile your

  6. Using the ACML Math Library

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

    ACML Math Library Using the ACML Math Library The AMD ACML math library is available on Euclid. This library is described at the ACML Math Library. To compile and link with it, ...

  7. Applied Math & Software

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

    Math & Software - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us ... Arctic Climate Measurements Global Climate Models Software Sustainable Subsurface ...

  8. Information Science, Computing, Applied Math

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

    Information Science, Computing, Applied Math Information Science, Computing, Applied Math National security depends on science and technology. The United States relies on Los ...

  9. Math Library Performance

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

    Math Library Performance Math Library Performance Fully optimizing a given application's performance often requires a deep understanding of the source, an accurate profile for a representative run, and the ability to have changes to the source accepted upstream. However, in many cases, significant performance gains can be achieved by simply optimizing the code over the matrix of possible compilers, compiler options and libraries available on a given machine. Here, we explore the performance

  10. Applied Math & Software

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

    Math & Software - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear

  11. Using the ACML Math Library

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

    ACML Math Library Using the ACML Math Library The AMD ACML math library is available on Euclid. This library is described at the ACML Math Library. To compile and link with it, load the ACML library and include the $ACML environment variable as part of your compile/link line: % module load acml % mpicc -o cblas cblas.c $ACML If you have the gnu compilers loaded, use the acml-gnu module instead. Last edited: 2011-04-06 13:02:19

  12. Activation of 200 MW refusegenerated CHP upward regulation effect...

    Open Energy Info (EERE)

    EU Smart Grid Projects Map1 Overview Waste CHP plants can be used in the electricity market for upward regulation by bypassing the steam turbine. The technical design for this...

  13. List of Math Libraries

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

    Libraries List List of Math Libraries Package Platform Version Module Install Date Date Made Default A Fortran interface to the GNU Scientific Library (GSL) edison 1.0.0 fgsl/1.0.0 2015-04-14 2016-08-31 ACML cori 5.3.1 acml/5.3.1 2015-12-22 2016-06-30 ACML cori 6.1.0.31 acml/6.1.0.31 2015-12-22 ACML edison 5.3.1 acml/5.3.1 2016-01-26 2016-08-31 ACML edison 6.1.0.31 acml/6.1.0.31 2016-01-26 acml genepool 5.1.0 acml/5.1.0 2012-07-07 acml genepool_sl6 5.1.0 acml/5.1.0 2015-03-06 acml phoebe 5.1.0

  14. Information Science, Computing, Applied Math

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

    Information Science, Computing, Applied Math Information Science, Computing, Applied Math National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. Computer, Computational, and Statistical Sciences (CCS)» High Performance Computing (HPC)» Extreme Scale Computing, Co-design» supercomputing into the future Overview Los Alamos Asteroid Killer

  15. Real-time sub-<math display='inline'>math>ngstrom...

    Office of Scientific and Technical Information (OSTI)

    Real-time sub-<math display'inline'><math>ngstrom imaging of reversible and irreversible conformations in rhodium catalysts and graphene Kisielowski, Christian; Wang,...

  16. Phase diagram of Josephson junction between<math

    Office of Scientific and Technical Information (OSTI)

    diagram of Josephson junction between<math display'inline'>s<math>and display'inline'>s<math>superconductors in the dirty limit...

  17. Math of Popping Bubbles in a Foam

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

    Math of Popping Bubbles in a Foam Math of Popping Bubbles in a Foam Berkeley Lab researchers mathematically describe the complex evolution and disappearance of foamy bubbles May 9, ...

  18. Math and Science Academy for Teachers

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

    for Teachers (MSA) is an intensive three-year program designed to support whole-school continuous improvement in math and science teaching and learning. L NL Math and Science...

  19. math.jpeg | OSTI, US Dept of Energy Office of Scientific and Technical

    Office of Scientific and Technical Information (OSTI)

    Information math.jpeg

  20. Northern New Mexico Math & Science Academy

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

    Northern New Mexico Math & Science Academy for Teachers (MSA) Program Description MSA is an intensive and comprehensive professional development program for K-12 teachers. Participants commit to attend a three-week Summer Institute for three years during which they study best practices in math and science education. Teachers also receive instructional support and additional math and science content workshops during the school year. Program Objectives 1. To increase teachers' content

  1. Regional math teacher wins presidential award

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

    Regional math teacher wins presidential award Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Regional math teacher wins presidential award Regional economic growth celebrated February 1, 2014 Vivian Valencia, (fourth-grade math teacher at the San Juan Elementary School in Espanola) recently won the Presidential Award for Excellence in Mathematics and Science Teaching Vivian Valencia,

  2. Math and Science Academy for Teachers

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

    Teachers (K-12) » Math & Science Academy for Teachers Northern New Mexico Math & Science Academy for Teachers The Laboratory's Math and Science Academy (MSA) provides quality STEM education professional development for teachers in participating schools and districts. Contacts Community Partnerships Office (505) 665-4400 Lorenzo Gonzales (505) 699-4050 Email Zachary Leonard (505) 699-4053 Email Monica J. Martinez-Archuleta (505) 500-6076 Email Randy Merker (505) 500-5898 Email Teacher

  3. Northern New Mexico Math & Science Academy

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

    Northern New Mexico Math & Science Academy for Teachers (MSA) Program Description MSA is an intensive and comprehensive professional development program for K-12 teachers....

  4. Scientists compose complex math equations to replicate behaviors...

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

    Climate Models: Rob Jacob Scientists compose complex math equations to replicate behaviors ... It's math in action. A global model depends on submodels Submodels can be broken into two ...

  5. Updated Radiation Exhibit Unveiled at Math and Science Center...

    Office of Environmental Management (EM)

    Updated Radiation Exhibit Unveiled at Math and Science Center in Grand Junction, Colorado Updated Radiation Exhibit Unveiled at Math and Science Center in Grand Junction, Colorado ...

  6. Former NERSC Consultant Mentors Math, Computer Science Students

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

    Former NERSC Consultant Mentors Math, Computer Science Students Former NERSC Consultant Mentors Math, Computer Science Students March 10, 2015 Frank Hale, a former consultant in ...

  7. The detection of upwardly propagating waves channeling energy from the chromosphere to the low corona

    SciTech Connect (OSTI)

    Freij, N.; Nelson, C. J.; Mumford, S.; Erdlyi, R.; Scullion, E. M.; Wedemeyer, S.

    2014-08-10

    There have been ubiquitous observations of wave-like motions in the solar atmosphere for decades. Recent improvements to space- and ground-based observatories have allowed the focus to shift to smaller magnetic structures on the solar surface. In this paper, high-resolution ground-based data taken using the Swedish 1 m Solar Telescope is combined with co-spatial and co-temporal data from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO) satellite to analyze running penumbral waves (RPWs). RPWs have always been thought to be radial wave propagation that occurs within sunspots. Recent research has suggested that they are in fact upwardly propagating field-aligned waves (UPWs). Here, RPWs within a solar pore are observed for the first time and are interpreted as UPWs due to the lack of a penumbra that is required to support RPWs. These UPWs are also observed co-spatially and co-temporally within several SDO/AIA elemental lines that sample the transition region and low corona. The observed UPWs are traveling at a horizontal velocity of around 17 0.5 km s{sup 1} and a minimum vertical velocity of 42 21 km s{sup 1}. The estimated energy of the waves is around 150 W m{sup 2}, which is on the lower bound required to heat the quiet-Sun corona. This is a new, yet unconsidered source of wave energy within the solar chromosphere and low corona.

  8. Ion acoustic solitons in Earth's upward current region

    SciTech Connect (OSTI)

    Main, D. S.; Scholz, C.; Newman, D. L.; Ergun, R. E.

    2012-07-15

    The formation and evolution of ion acoustic solitons in Earth's auroral upward current region are studied using one- and two-dimensional (2D) electrostatic particle-in-cell simulations. The one-dimensional simulations are confined to processes that occur in the auroral cavity and include four plasma populations: hot electrons, H{sup +} and O{sup +} anti-earthward ion beams, and a hot H{sup +} background population. Ion acoustic solitons are found to form for auroral-cavity ion beams consistent with acceleration through double-layer (DL) potentials measured by FAST. A simplified one-dimensional model simulation is then presented in order to isolate the mechanisms that lead to the formation of the ion acoustic soliton. Results of a two-dimensional simulation, which include both the ionosphere and the auroral cavity, separated by a low-altitude DL, are then presented in order to confirm that the soliton forms in a more realistic 2D geometry. The 2D simulation is initialized with a U-shaped potential structure that mimics the inferred shape of the low altitude transition region based on observations. In this simulation, a soliton localized perpendicular to the geomagnetic field is observed to form and reside next to the DL. Finally, the 2D simulation results are compared with FAST data and it is found that certain aspects of the data can be explained by assuming the presence of an ion acoustic soliton.

  9. Upward-facing Lithium Flash Evaporator for NSTX-U

    SciTech Connect (OSTI)

    Roquemore, A. L.

    2013-07-09

    NSTX plasma performance has been significantly enhanced by lithium conditioning [1]. To date, the lower divertor and passive plates have been conditioned by downward facing lithium evaporators (LITER) as appropriate for lower null plasmas. The higher power operation expected from NSTX-U requires double null plasma operation in order to distribute the heat flux between the upper and lower divertors making it desirable to coat the upper divertor region with Li as well. An upward aiming LITER (U-LITER) is presently under development and will be inserted into NSTX-U using a horizontal probe drive located in a 6" upper midplane port. In the retracted position the evaporator will be loaded with up to 300 mg of Li granules utilizing one of the calibrated NSTX Li powder droppers[2]. The evaporator will then be inserted into the vessel in a location within the shadow of the RF limiters and will remain in the vessel during the discharge. About 10 seconds before a discharge, it will be rapidly heated and the lithium completely evaporated onto the upper divertor, thus avoiding the complication of a shutter that prevents evaporation during the shot when the diagnostic shutters are open. The minimal time interval between the evaporation and the start of the discharge will avoid the passivation of the lithium by residual gases and enable the study of the conditioning effects of un-passivated Li surfaces [3]. Two methods are being investigated to accomplish the rapid (few second) heating of the lithium. A resistive method relies on passing a large current through a Li filled crucible. A second method requires using a 3 kW e-beam gun to heat the Li. In this paper the evaporator systems will be described and the pros and cons of each heating method will be discussed.

  10. Boosting Native American students' math scores

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

    Boosting Native American students' math scores Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Boosting Native American students' math scores Professional development opportunities for teachers provide essential foundation May 5, 2014 Mara Herrera teaches a young student at San Felipe Pueblo Elementary School. Mara Herrera teaches a young student at San Felipe Pueblo Elementary School.

  11. Physical Uncertainty Bounds (PUB)

    SciTech Connect (OSTI)

    Vaughan, Diane Elizabeth; Preston, Dean L.

    2015-03-19

    This paper introduces and motivates the need for a new methodology for determining upper bounds on the uncertainties in simulations of engineered systems due to limited fidelity in the composite continuum-level physics models needed to simulate the systems. We show that traditional uncertainty quantification methods provide, at best, a lower bound on this uncertainty. We propose to obtain bounds on the simulation uncertainties by first determining bounds on the physical quantities or processes relevant to system performance. By bounding these physics processes, as opposed to carrying out statistical analyses of the parameter sets of specific physics models or simply switching out the available physics models, one can obtain upper bounds on the uncertainties in simulated quantities of interest.

  12. MidSchoolMath conference helps teachers, students and regional...

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

    Top secret math problem The MidSchoolMath conference is founded on the idea that storytelling, the oldest approach to human learning, has the power to transform student attitudes, ...

  13. Renormalization Group Flows, Cycles, and<math display='inline...

    Office of Scientific and Technical Information (OSTI)

    Group Flows, Cycles, and<math display'inline'>c<math>-Theorem Folklore Curtright, Thomas L.; Jin, Xiang; Zachos, Cosmas K. Not Available American Physical Society None...

  14. Imagine Education recognized for innovative approach to math education

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

    Innovative approach to math education Imagine Education recognized for innovative approach to math education Endeavored to remake the way middle-school math is taught through its first-of-its-kind, story-based, online math game, called Ko's Journey. July 20, 2011 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma

  15. Effects of Increased Upward Flux of Saline Water Caused by CO2 Storage or Other Factors

    SciTech Connect (OSTI)

    Murdoch, Lawrence; Xie, Shuang; Falta, Ronald W.; Yonkofski, Catherine MR

    2015-08-01

    Injection of CO2 in deep saline aquifers is being considered to reduce greenhouse gases in the atmosphere, and this process is expected to increase the pressure in these deep aquifers. One potential consequence of pressurization is an increase in the upward flux of saline water. Saline groundwater occurs naturally at shallow depths in many sedimentary basins, so an upward flux of solutes could degrade the quality of freshwater aquifers and threaten aquatic ecosystems. One problem could occur where saline water flowed upward along preferential paths, like faults or improperly abandoned wells. Diffuse upward flow through the natural stratigraphy could also occur in response to basin pressurization. This process would be slower, but diffuse upward flow could affect larger areas than flow through preferential paths, and this motivated us to evaluate this process. We analyzed idealized 2D and 3D geometries representing the essential details of a shallow, freshwater aquifer underlain by saline ground water in a sedimentary basin. The analysis was conducted in two stages, one that simulated the development of a freshwater aquifer by flushing out saline water, and another that simulated the effect of a pulse-like increase in the upward flux from the basin. The results showed that increasing the upward flux from a basin increased the salt concentration and mass loading of salt to streams, and decrease the depth to the fresh/salt transition. The magnitude of these effects varied widely, however, from a small, slow process that would be challenging to detect, to a large, rapid response that could be an environmental catastrophe. The magnitude of the increased flux, and the initial depth to the fresh/salt transition in groundwater controlled the severity of the response. We identified risk categories for salt concentration, mass loading, and freshwater aquifer thickness, and we used these categories to characterize the severity of the response. This showed that risks would

  16. Math of Popping Bubbles in a Foam

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

    Math of Popping Bubbles in a Foam Math of Popping Bubbles in a Foam Berkeley Lab researchers mathematically describe the complex evolution and disappearance of foamy bubbles May 9, 2013 Media Contacts: UC Berkeley: Robert Sanders, rsanders@berkeley.edu, (510) 643-6998 Berkeley Lab: Linda Vu, lvu@lbl.gov, (510) 495-2404 Written By Robert Sanders Bubble baths and soapy dishwater, the refreshing head on a beer and the luscious froth on a cappuccino. All are foams, beautiful yet ephemeral as the

  17. UPWARD MOVEMENT OF PLUTONIUM TO SURFACE SEDIMENTS DURING AN 11-YEAR FIELD STUDY

    SciTech Connect (OSTI)

    Kaplan, D.; Beals, D.; Cadieux, J.; Halverson, J.

    2010-01-25

    An 11-y lysimeter study was established to monitor the movement of Pu through vadose zone sediments. Sediment Pu concentrations as a function of depth indicated that some Pu moved upward from the buried source material. Subsequent numerical modeling suggested that the upward movement was largely the result of invading grasses taking up the Pu and translocating it upward. The objective of this study was to determine if the Pu of surface sediments originated from atmosphere fallout or from the buried lysimeter source material (weapons-grade Pu), providing additional evidence that plants were involved in the upward migration of Pu. The {sup 240}Pu/{sup 239}Pu and {sup 242}Pu/{sup 239}Pu atomic fraction ratios of the lysimeter surface sediments, as determined by Thermal Ionization Mass Spectroscopy (TIMS), were 0.063 and 0.00045, respectively; consistent with the signatures of the weapons-grade Pu. Our numerical simulations indicate that because plants create a large water flux, small concentrations over multiple years may result in a measurable accumulation of Pu on the ground surface. These results may have implications on the conceptual model for calculating risk associated with long-term stewardship and monitored natural attenuation management of Pu contaminated subsurface and surface sediments.

  18. Intensity of Upward Muon Flux Due to Cosmic-Ray Neutrinos Produced in the Atmosphere

    DOE R&D Accomplishments [OSTI]

    Lee, T. D.; Robinson, H.; Schwartz, M.; Cool, R.

    1963-06-01

    Calculations were performed to determine the upward going muon flux leaving the earth's surface after production by cosmic-ray neutrinos in the crust. Only neutrinos produced in the earth's atmosphere are considered. Rates of the order of one per 100 sq m/day might be expected if an intermediate boson exists and has a mass less than 2 Bev. (auth)

  19. Sources of biogenic methane to form marine gas hydrates: In situ production or upward migration?

    SciTech Connect (OSTI)

    Paull, C.K.; Ussler, W. III; Borowski, W.S.

    1993-09-01

    Potential sources of biogenic methane in the Carolina Continental Rise -- Blake Ridge sediments have been examined. Two models were used to estimate the potential for biogenic methane production: (1) construction of sedimentary organic carbon budgets, and (2) depth extrapolation of modern microbial production rates. While closed-system estimates predict some gas hydrate formation, it is unlikely that >3% of the sediment volume could be filled by hydrate from methane produced in situ. Formation of greater amounts requires migration of methane from the underlying continental rise sediment prism. Methane may be recycled from below the base of the gas hydrate stability zone by gas hydrate decomposition, upward migration of the methane gas, and recrystallization of gas hydrate within the overlying stability zone. Methane bubbles may also form in the sediment column below the depth of gas hydrate stability because the methane saturation concentration of the pore fluids decreases with increasing depth. Upward migration of methane bubbles from these deeper sediments can add methane to the hydrate stability zone. From these models it appears that recycling and upward migration of methane is essential in forming significant gas hydrate concentrations. In addition, the depth distribution profiles of methane hydrate will differ if the majority of the methane has migrated upward rather than having been produced in situ.

  20. Former NERSC Consultant Mentors Math, Computer Science Students

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

    Former NERSC Consultant Mentors Math, Computer Science Students Former NERSC Consultant Mentors Math, Computer Science Students March 10, 2015 Frank Hale, a former consultant in NERSC's User Services Group (USG) who currently tutors math at Diablo Valley College (DVC) in Pleasant Hill, CA, recently brought a group of computer science enthusiasts from the college to NERSC for a tour. Hale, the first person hired into the USG when NERSC relocated from Lawrence Livermore National Laboratory to

  1. Girls learn about careers in math and science

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

    Girls learn about careers In math and science Girls learn about careers in math and science Expanding Your Horizons is designed to introduce girls to a variety of careers that require math and science backgrounds, and to stress the importance of taking math and science classes during high school. March 5, 2008 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from

  2. Science, Technology, Engineering and Math (STEM) Education Summit

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

    STEM Education Summit STEM Education Summit The Laboratory views its investment in science, technology, engineering and math (STEM) education as strengthening the Lab's strategic...

  3. Scientists Help Teachers With Their Math and Science (EdWeek...

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

    https:www.jlab.orgnewsarticlesscientists-help-teachers-their-math-and-science-edweekorg Scientists Help Teachers With Their Math and Science By Sean Cavanagh, EdWeek.org ...

  4. Fractional diffusion on bounded domains

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

    Defterli, Ozlem; D'Elia, Marta; Du, Qiang; Gunzburger, Max Donald; Lehoucq, Richard B.; Meerschaert, Mark M.

    2015-03-13

    We found that the mathematically correct specification of a fractional differential equation on a bounded domain requires specification of appropriate boundary conditions, or their fractional analogue. In this paper we discuss the application of nonlocal diffusion theory to specify well-posed fractional diffusion equations on bounded domains.

  5. Students Sharpen Science and Math Skills at Middle School Science...

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

    Students Sharpen Science and Math Skills at Middle School Science Bowl March 8, 2004 Golden, Colo. - The buzzer has sounded, the clock is ticking and all eyes are on you-what is ...

  6. Got Questions about Women in Science, Tech, Engineering, or Math...

    Office of Environmental Management (EM)

    Math (STEM) on Twitter on Thursday, March 22 at 2:30pm EDT by following the hashtag STEM. Gloria B. Smith Deputy Director, Office of Diversity & Inclusion How can I participate? ...

  7. Empirical Math Model: Ideal Gas Law | Department of Energy

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

    Empirical Math Model: Ideal Gas Law Empirical Math Model: Ideal Gas Law January 29, 2013 - 9:54am Addthis What are the key facts? Empirical models are generally most useful in describing conditions close to the experiments used to develop or calibrate them. Predictive tools are essential to understanding phenomena that can not be described experimentally, like used fuel behavior over thousands of years in a repository. Predictability is measured by understanding errors where they are introduced

  8. Mentoring to Increase Diversity in Science, Tech, Engineering and Math |

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

    Department of Energy Mentoring to Increase Diversity in Science, Tech, Engineering and Math Mentoring to Increase Diversity in Science, Tech, Engineering and Math Mentoring is particularly suited in STEM to help with diversity because STEM is a social networking activity. The Department provides mentoring through programs at colleges/Universities, research internshipa, and professional societies. Read this presentation to learn more. mentoring for diversity October 2011.pptx (7.97 MB) More

  9. Math and Science Academy helps Native American schools empower teachers

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

    Math and Science Academy helps Native American schools empower teachers Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Math and Science Academy helps Native American schools empower teachers Ongoing professional support is key October 1, 2014 Jemez Day School teacher Patrick Lewis and young student. Jemez Day School teacher Patrick Lewis and young student. Contact Community Programs

  10. Effect of ignition conditions on upward flame spread on a composite material in a corner configuration

    SciTech Connect (OSTI)

    Ohlemiller, T.; Cleary, T.; Shields, J.

    1996-12-31

    This paper focuses on the issue of fire growth on composite materials beyond the region immediately subjected to an ignition source. Suppression of this growth is one of the key issues in realizing the safe usage of composite structural materials. A vinyl ester/glass composite was tested in the form of a 90{degrees} comer configuration with an inert ceiling segment 2.44 m above the top of the fire source. The igniter was a propane burner, either 23 or 38 cm in width with power output varied from 30 to 150 Kw. Upward flame spread rate and heat release rate were measured mainly for a brominated vinyl ester resin but limited results were also obtained for a non-flame retarded vinyl ester and a similar composite coated with an intumescent paint. Rapid fire growth beyond the igniter region was seen for the largest igniter power case; the intumescent coating successfully prevented fire growth for this case.

  11. Exotic equilibria of Harary graphs and a new minimum degree lower bound for synchronization

    SciTech Connect (OSTI)

    Canale, Eduardo A.; Monzn, Pablo

    2015-02-15

    This work is concerned with stability of equilibria in the homogeneous (equal frequencies) Kuramoto model of weakly coupled oscillators. In 2012 [R. Taylor, J. Phys. A: Math. Theor. 45, 115 (2012)], a sufficient condition for almost global synchronization was found in terms of the minimum degreeorder ratio of the graph. In this work, a new lower bound for this ratio is given. The improvement is achieved by a concrete infinite sequence of regular graphs. Besides, non standard unstable equilibria of the graphs studied in Wiley et al. [Chaos 16, 015103 (2006)] are shown to exist as conjectured in that work.

  12. Spin and photophysics of carbon-antisite vacancy defect in <math...

    Office of Scientific and Technical Information (OSTI)

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

  13. File:The MacGyver Wind Math Competition.pdf | Open Energy Information

    Open Energy Info (EERE)

    The MacGyver Wind Math Competition.pdf Jump to: navigation, search File File history File usage Metadata File:The MacGyver Wind Math Competition.pdf Size of this preview: 800 ...

  14. Structural, magnetic, and superconducting properties of pulsed-laser-deposition-grown <math>La1.85math> <math>Sr0.15math> <math>CuO4math> / <math>La2/3math> <math>Ca1/3math> <math>MnO3math> superlattices on (001)-oriented <math>LaSrAlO4math> substrates

    SciTech Connect (OSTI)

    Das, S.; Sen, K.; Marozau, I.; Uribe-Laverde, M. A.; Biskup, N.; Varela, M.; Khaydukov, Y.; Soltwedel, O.; Keller, T.; Döbeli, M.; Schneider, C. W.; Bernhard, C.

    2014-03-12

    Epitaxial <math>La1.85math> <math>Sr0.15math> <math>CuO4math> / <math>La2/3math> <math>Ca1/3math> <math>MnO3math> (LSCO/LCMO) superlattices (SL) on (001)- oriented LaSrAlO4 substrates have been grown with pulsed laser deposition (PLD) technique. Their structural, magnetic and superconducting properties have been determined with in-situ reflection high energy electron diffraction (RHEED), x-ray diffraction, specular neutron reflectometry, scanning transmission electron microscopy (STEM), electric transport, and magnetization measurements. We find that despite the large mismatch between the in-plane lattice parameters of LSCO (a = 0.3779 nm) and LCMO (a = 0.387 nm) these superlattices can be grown epitaxially and with a high crystalline quality. While the first LSCO layer remains clamped to the LSAO substrate, a sizeable strain relaxation occurs already in the first LCMO layer. The following LSCO and LCMO layers adopt a nearly balanced state in which the tensile and compressive strain effects yield alternating in-plane lattice parameters with an almost constant average value. No major defects are observed in the LSCO layers, while a significant number of vertical antiphase boundaries are found in the LCMO layers. The LSCO layers remain superconducting with a relatively high superconducting onset temperature of Tconset ≈ 36 K. The macroscopic superconducting response is also evident in the magnetization data due to a weak diamagnetic signal below 10 K for H ∥ ab and a sizeable paramagnetic shift for H ∥ c that can be explained in terms of a vortex-pinning-induced flux compression. The LCMO layers maintain a

  15. Los Alamos Middle School team wins regional MathCounts competition

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

    Los Alamos Middle School team wins Regional MathCounts competition Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Los Alamos Middle School wins regional MathCounts event Competes against 60 other middle schools for the title. March 1, 2013 Los Alamos Middle School won the regional MathCounts competition. Los Alamos Middle School won the regional MathCounts competition. Contacts Editor

  16. Correlation effects and bound states

    SciTech Connect (OSTI)

    Zinovjev, G. M.; Molodtsov, S. V.

    2012-11-15

    Bound states in a simple quark model that are due to correlation effects are analyzed. The confining properties of this model in meson (quark-antiquark and diquark) channels manifest themselves at any quark momenta, and an extra potential field may only enhance the confining effect.

  17. Science, Technology, Engineering, and Math (STEM) Education Summit

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

    STEM Education Summit STEM Education Summit The Laboratory views its investment in science, technology, engineering and math (STEM) education as strengthening the Lab's strategic direction and developing its current and future workforce. Contacts Education Janelle Vigil-Maestas Community Relations & Partnerships (505) 665-4329 Email Student Challenge A LANL STEM Education Summit was held in Los Alamos in April 2013. Participants at the summit reviewed the Lab's commitments in improving STEM

  18. High School Girls Honored for Math, Science Achievements

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

    School Girls Honored for Math, Science Achievements - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste

  19. Measurement of the direct <math display='inline'>CPmath> -violating parameter <math display='inline'>ACPmath> in the decay <math display='inline'>D+K-π+π+math>

    SciTech Connect (OSTI)

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Askew, A.; Atkins, S.; Augsten, K.; Avila, C.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Borysova, M.; Brandt, A.; Brandt, O.; Brock, R.; Bross, A.; Brown, D.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Buszello, C. P.; Camacho-Pérez, E.; Casey, B. C. K.; Castilla-Valdez, H.; Caughron, S.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M. -C.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, V. N.; Fauré, A.; Feng, L.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Gogota, O.; Golovanov, G.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J. -F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Howley, I.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jayasinghe, A.; Jeong, M. S.; Jesik, R.; Jiang, P.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kajfasz, E.; Karmanov, D.; Katsanos, I.; Kaur, M.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kiselevich, I.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kumar, A.; Kupco, A.; Kurča, T.; Kuzmin, V. A.; Lammers, S.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, H.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Mansour, J.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Mulhearn, M.; Nagy, E.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nguyen, H. T.; Nunnemann, T.; Orduna, J.; Osman, N.; Osta, J.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Pleier, M. -A.; Podstavkov, V. M.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Ratoff, P. N.; Razumov, I.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Santos, A. S.; Savage, G.; Savitskyi, M.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shaw, S.; Shchukin, A. A.; Simak, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Soustruznik, K.; Stark, J.; Stoyanova, D. A.; Strauss, M.; Suter, L.; Svoisky, P.; Titov, M.; Tokmenin, V. V.; Tsai, Y. -T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Verkheev, A. Y.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vilanova, D.; Vokac, P.; Wahl, H. D.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Williams, M. R. J.; Wilson, G. W.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yang, S.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yin, H.; Yip, K.; Youn, S. W.; Yu, J. M.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.

    2014-12-01

    We measure the direct math display="inline">CPmath>-violating parameter math display="inline">ACPmath> for the decay of the charged charm meson, math display="inline">D+K-π+π+math> (and charge conjugate), using the full math display="inline">10.4 fb-1math> sample of math display="inline">pp¯math> collisions at math display="inline">s=1.96 TeVmath> collected by the D0 detector at the Fermilab Tevatron collider. We extract the raw reconstructed charge asymmetry by fitting the invariant mass distributions for the sum and difference of charge-specific samples. This quantity is then corrected for detector-related asymmetries using data-driven methods and for possible physics asymmetries (from math display="inline">BDmath

  20. Calling Excellent Math and Science Teachers-- Einstein Fellowship Deadline is January 4

    Broader source: Energy.gov [DOE]

    Elementary and secondary math and science teachers are eligible the fellowship that bring them to DC to share their teaching expertise with policy makers.

  1. DOE Applied Math Summit | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    systems, mathematics for complex distributed systems, uncertainty quantification, mathematics for analysis of petascale data, and joint applied math computer science institutes. ...

  2. Bounds on Transport Coefficients of Porous Media

    SciTech Connect (OSTI)

    Berryman, J G

    2005-03-21

    An analytical formulation of conductivity bounds by Bergman and Milton is used in a different way to obtain rigorous bounds on the real transport coefficients (electrical conductivity, thermal conductivity, and/or fluid permeability) of a fluid-saturated porous medium. These bounds do not depend explicitly on the porosity, but rather on two formation factors--one associated with the pore space and the other with the solid frame. Hashin-Shtrikman bounds for transport in random polycrystals of porous-material laminates will also be discussed.

  3. COLLOQUIUM: Fluke: The Math and Myth of Coincidence | Princeton Plasma

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

    Physics Lab March 30, 2016, 4:15pm to 5:30pm Colloquia MBG Auditorium COLLOQUIUM: Fluke: The Math and Myth of Coincidence Professor Joseph Mazur Marlboro College What is the connection between mathematical law and observed experience? When we look at coincidences mathematically, we find that the odds are far better than any of us would have thought. Probability asks: What are the chances? We answer with a number. But we also ask ourselves that same question when we encounter the strangest

  4. Performance bound for real OTEC heat engines

    SciTech Connect (OSTI)

    Wu, C.

    1987-01-01

    Maximum power and efficiency at the maximum power of an irreversible OTEC heat engine are treated. When time is explicitly considered in the energy exchanges between the heat engine and its surroundings, it is found that there is a bound on the efficiency of the real OTEC heat engine at the maximum power condition. This bound can guide the evaluation of existing OTEC systems or influence design of future OTEC heat engines.

  5. Calculations of some weakly bound diatomic molecular negative ions

    SciTech Connect (OSTI)

    Li, Y.; Lin, C.D. )

    1999-09-01

    We examine the existence of stable bound states of some diatomic molecular ions where the neutral molecule itself is either unbound or barely bound. Two bound states have been found for the HeH[sup [minus

  6. Lab receives $25,000 for Math and Science Academy from Chevron Energy

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

    Technology Company Lab receives $25,000 for Math and Science Academy Lab receives $25,000 for Math and Science Academy from Chevron Energy Technology Company The program is conducted by LANL in cooperation with its regional education, business, and government partners. November 30, 2009 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience,

  7. Experimental study of forced convection heat transfer during upward and downward flow of helium at high pressure and high temperature

    SciTech Connect (OSTI)

    Francisco Valentin; Narbeh Artoun; Masahiro Kawaji; Donald M. McEligot

    2015-08-01

    Fundamental high pressure/high temperature forced convection experiments have been conducted in support of the development of a Very High Temperature Reactor (VHTR) with a prismatic core. The experiments utilize a high temperature/high pressure gas flow test facility constructed for forced convection and natural circulation experiments. The test section has a single 16.8 mm ID flow channel in a 2.7 m long, 108 mm OD graphite column with four 2.3kW electric heater rods placed symmetrically around the flow channel. This experimental study presents the role of buoyancy forces in enhancing or reducing convection heat transfer for helium at high pressures up to 70 bar and high temperatures up to 873 degrees K. Wall temperatures have been compared among 10 cases covering the inlet Re numbers ranging from 500 to 3,000. Downward flows display higher and lower wall temperatures in the upstream and downstream regions, respectively, than the upward flow cases due to the influence of buoyancy forces. In the entrance region, convection heat transfer is reduced due to buoyancy leading to higher wall temperatures, while in the downstream region, buoyancyinduced mixing causes higher convection heat transfer and lower wall temperatures. However, their influences are reduced as the Reynolds number increases. This experimental study is of specific interest to VHTR design and validation of safety analysis codes.

  8. Experimental investigation on heat transfer and frictional characteristics of vertical upward rifled tube in supercritical CFB boiler

    SciTech Connect (OSTI)

    Yang, Dong; Pan, Jie; Zhu, Xiaojing; Bi, Qincheng; Chen, Tingkuan; Zhou, Chenn Q.

    2011-02-15

    Water wall design is a key issue for supercritical Circulating Fluidized Bed (CFB) boiler. On account of the good heat transfer performance, rifled tube is applied in the water wall design of a 600 MW supercritical CFB boiler in China. In order to investigate the heat transfer and frictional characteristics of the rifled tube with vertical upward flow, an in-depth experiment was conducted in the range of pressure from 12 to 30 MPa, mass flux from 230 to 1200 kg/(m{sup 2} s), and inner wall heat flux from 130 to 720 kW/m{sup 2}. The wall temperature distribution and pressure drop in the rifled tube were obtained in the experiment. The normal, enhanced and deteriorated heat transfer characteristics were also captured. In this paper, the effects of pressure, inner wall heat flux and mass flux on heat transfer characteristics are analyzed, the heat transfer mechanism and the frictional resistance performance are discussed, and the corresponding empirical correlations are presented. The experimental results show that the rifled tube can effectively prevent the occurrence of departure from nucleate boiling (DNB) and keep the tube wall temperature in a permissible range under the operating condition of supercritical CFB boiler. (author)

  9. Upward shift of the vortex solid phase in high-temperature-superconducting wires through high density nanoparticle addition

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

    Miura, Masashi; Maiorov, Boris; Balakirev, Fedor F.; Kato, Takeharu; Sato, Michio; Takagi, Yuji; Izumi, Teruo; Civale, Leonardo

    2016-02-08

    Here, we show a simple and effective way to improve the vortex irreversibility line up to very high magnetic fields (60T) by increasing the density of second phase BaZrO3 nanoparticles. (Y0.77,Gd0.23)Ba2Cu3Oy films were grown on metal substrates with different concentration of BaZrO3 nanoparticles by the metal organic deposition method. We find that upon increase of the BaZrO3 concentration, the nanoparticle size remains constant but the twin-boundary density increases. Up to the highest nanoparticle concentration (n ~ 1.3 × 1022/m3), the irreversibility field (Hirr) continues to increase with no sign of saturation up to 60 T, although the vortices vastly outnumbermore » pinning centers. We find extremely high Hirr, namely Hirr = 30 T (H||45°) and 24 T (H||c) at 65 K and 58 T (H||45°) and 45 T (H||c) at 50K. The difference in pinning landscape shifts the vortex solid-liquid transition upwards, increasing the vortex region useful for power applications, while keeping the upper critical field, critical temperature and electronic mass anisotropy unchanged.« less

  10. Theory and Modeling of Weakly Bound/Physisorbed Materials for...

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

    Theory and Modeling of Weakly BoundPhysisorbed Materials for Hydrogen Storage Theory and Modeling of Weakly BoundPhysisorbed Materials for Hydrogen Storage Presentation on the ...

  11. Crystal structure of elongation factor 4 bound to a clockwise...

    Office of Scientific and Technical Information (OSTI)

    Crystal structure of elongation factor 4 bound to a clockwise ratcheted ribosome Citation Details In-Document Search Title: Crystal structure of elongation factor 4 bound to a ...

  12. Bound states in the Higgs model

    SciTech Connect (OSTI)

    Di Leo, L.; Darewych, J.W. )

    1994-02-01

    We derive relativistic wave equations for the bound states of two Higgs bosons within the Higgs sector of the minimal standard model. The variational method and the Hamiltonian formalism of QFT are used to obtain the equations using a simple [vert bar][ital hh][r angle]+[vert bar][ital hhh][r angle] Fock-space ansatz. We present approximate solutions of these equations for a range of Higgs boson masses, and explore the parameter space which corresponds to the existence of two-Higgs-boson bound states.

  13. Efficiency bounds for nonequilibrium heat engines

    SciTech Connect (OSTI)

    Mehta, Pankaj; Polkovnikov, Anatoli

    2013-05-15

    We analyze the efficiency of thermal engines (either quantum or classical) working with a single heat reservoir like an atmosphere. The engine first gets an energy intake, which can be done in an arbitrary nonequilibrium way e.g. combustion of fuel. Then the engine performs the work and returns to the initial state. We distinguish two general classes of engines where the working body first equilibrates within itself and then performs the work (ergodic engine) or when it performs the work before equilibrating (non-ergodic engine). We show that in both cases the second law of thermodynamics limits their efficiency. For ergodic engines we find a rigorous upper bound for the efficiency, which is strictly smaller than the equivalent Carnot efficiency. I.e. the Carnot efficiency can be never achieved in single reservoir heat engines. For non-ergodic engines the efficiency can be higher and can exceed the equilibrium Carnot bound. By extending the fundamental thermodynamic relation to nonequilibrium processes, we find a rigorous thermodynamic bound for the efficiency of both ergodic and non-ergodic engines and show that it is given by the relative entropy of the nonequilibrium and initial equilibrium distributions. These results suggest a new general strategy for designing more efficient engines. We illustrate our ideas by using simple examples. -- Highlights: ? Derived efficiency bounds for heat engines working with a single reservoir. ? Analyzed both ergodic and non-ergodic engines. ? Showed that non-ergodic engines can be more efficient. ? Extended fundamental thermodynamic relation to arbitrary nonequilibrium processes.

  14. Continuous-variable multipartite unlockable bound entangled Gaussian states

    SciTech Connect (OSTI)

    Zhang Jing

    2011-05-15

    We investigate continuous-variable (CV) multipartite unlockable bound entangled states. Comparing with the qubit multipartite unlockable bound entangled states, CV multipartite unlockable bound entangled states present some new and different properties. CV multipartite unlockable bound entangled states may serve as a useful quantum resource for new multiparty communication schemes. The experimental protocol for generating CV unlockable bound entangled states is proposed with a setup that is, at present, accessible.

  15. “Nodal Gap” induced by the incommensurate diagonal spin density modulation in underdoped high- <math id='M1'>Tcmath> superconductors

    SciTech Connect (OSTI)

    Zhou, Tao; Gao, Yi; Zhu, Jian -Xin

    2015-03-07

    Recently it was revealed that the whole Fermi surface is fully gapped for several families of underdoped cuprates. The existence of the finite energy gap along the <math id='M2'>dmath>-wave nodal lines (nodal gap) contrasts the common understanding of the <math id='M3'>dmath>-wave pairing symmetry, which challenges the present theories for the high-<math id='M4'>Tcmath>superconductors. Here we propose that the incommensurate diagonal spin-density-wave order can account for the above experimental observation. The Fermi surface and the local density of states are also studied. Our results are in good agreement with many important experiments in high-<math id='M5'>Tcmath>superconductors.

  16. Extremum seeking with bounded update rates

    SciTech Connect (OSTI)

    Scheinker, Alexander; Krsti?, Miroslav

    2013-11-16

    In this work, we present a form of extremum seeking (ES) in which the unknown function being minimized enters the systems dynamics as the argument of a cosine or sine term, thereby guaranteeing known bounds on update rates and control efforts. We present general n-dimensional optimization and stabilization results as well as 2D vehicle control, with bounded velocity and control efforts. For application to autonomous vehicles, tracking a source in a GPS denied environment with unknown orientation, this ES approach allows for smooth heading angle actuation, with constant velocity, and in application to a unicycle-type vehicle results in control ability as if the vehicle is fully actuated. Our stability analysis is made possible by the classic results of Kurzweil, Jarnik, Sussmann, and Liu, regarding systems with highly oscillatory terms. In our stability analysis, we combine the averaging results with a semi-global practical stability result under small parametric perturbations developed by Moreau and Aeyels.

  17. Methods and apparatus to produce stick-slip motion of logging tool attached to a wireline drawn upward by a continuously rotating wireline drum

    DOE Patents [OSTI]

    Vail, III, William Banning; Momii, Steven Thomas

    1998-01-01

    Methods and apparatus are described to produce stick-slip motion of a logging tool within a cased well attached to a wireline that is drawn upward by a continuously rotating wireline drum. The stick-slip motion results in the periodic upward movement of the tool in the cased well described in terms of a dwell time during which time the tool is stationary, the move time during which time the tool moves, and the stroke that is upward distance that the tool translates during the "slip" portion of the stick-slip motion. This method of measurement is used to log the well at different vertical positions of the tool. Therefore, any typical "station-to-station logging tool" may be modified to be a "continuous logging tool", where "continuous" means that the wireline drum continually rotates while the tool undergoes stick-slip motion downhole and measurements are performed during the dwell times when the tool is momentarily stationary. The stick-slip methods of operation and the related apparatus are particularly described in terms of making measurements of formation resistivity from within a cased well during the dwell times when the tool is momentarily stationary during the periodic stick-slip motion of the logging tool.

  18. Methods and apparatus to produce stick-slip motion of logging tool attached to a wireline drawn upward by a continuously rotating wireline drum

    DOE Patents [OSTI]

    Vail, W.B. III; Momii, S.T.

    1998-02-10

    Methods and apparatus are described to produce stick-slip motion of a logging tool within a cased well attached to a wireline that is drawn upward by a continuously rotating wireline drum. The stick-slip motion results in the periodic upward movement of the tool in the cased well described in terms of a dwell time during which time the tool is stationary, the move time during which time the tool moves, and the stroke that is upward distance that the tool translates during the ``slip`` portion of the stick-slip motion. This method of measurement is used to log the well at different vertical positions of the tool. Therefore, any typical ``station-to-station logging tool`` may be modified to be a ``continuous logging tool,`` where ``continuous`` means that the wireline drum continually rotates while the tool undergoes stick-slip motion downhole and measurements are performed during the dwell times when the tool is momentarily stationary. The stick-slip methods of operation and the related apparatus are particularly described in terms of making measurements of formation resistivity from within a cased well during the dwell times when the tool is momentarily stationary during the periodic stick-slip motion of the logging tool. 12 figs.

  19. Final work plan : supplemental upward vapor intrusion investigation at the former CCC/USDA grain storage facility in Hanover, Kansas.

    SciTech Connect (OSTI)

    LaFreniere, L. M.; Environmental Science Division

    2008-12-15

    The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), operated a grain storage facility at the northeastern edge of the city of Hanover, Kansas, from 1950 until the early 1970s. During this time, commercial grain fumigants containing carbon tetrachloride were in common use by the grain storage industry to preserve grain in their facilities. In February 1998, trace to low levels of carbon tetrachloride (below the maximum contaminant level [MCL] of 5.0 {micro}g/L) were detected in two private wells near the former grain storage facility at Hanover, as part of a statewide USDA private well sampling program that was implemented by the Kansas Department of Health and Environment (KDHE) near former CCC/USDA facilities. In 2007, the CCC/USDA conducted near-surface soil sampling at 61 locations and also sampled indoor air at nine residences on or adjacent to its former Hanover facility to address the residents concerns regarding vapor intrusion. Low levels of carbon tetrachloride were detected at four of the nine homes. The results were submitted to the KDHE in October 2007 (Argonne 2007). On the basis of the results, the KDHE requested sub-slab sampling and/or indoor air sampling (KDHE 2007). This Work Plan describes, in detail, the proposed additional scope of work requested by the KDHE and has been developed as a supplement to the comprehensive site investigation work plan that is pending (Argonne 2008). Indoor air samples collected previously from four homes at Hanover were shown to contain the carbon tetrachloride at low concentrations (Table 2.1). It cannot be concluded from these previous data that the source of the detected carbon tetrachloride is vapor intrusion attributable to former grain storage operations of the CCC/USDA at Hanover. The technical objective of the vapor intrusion investigation described here is to assess the risk to human health due to the potential for upward migration of carbon tetrachloride and

  20. High School Girls Honored for Math, Science Achievements at Sandia National Laboratory

    Broader source: Energy.gov [DOE]

    Now in its 23rd year, the Math and Science Awards program is sponsored by the Sandia Women’s Connection. This year’s event honored more students, with the addition of four high schools in Oakland, Calif., and included recognition of the students by federal and state officials. Teachers from 15 high schools in Livermore, Dublin, Pleasanton, Tracy, Manteca and Oakland nominated high school juniors whom they deemed outstanding in math and science, so the students can include the award on college and scholarship applications.

  1. #WomenInSTEM: Using Science and Math to Power the Globe | Department of

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

    Energy Using Science and Math to Power the Globe #WomenInSTEM: Using Science and Math to Power the Globe May 27, 2014 - 5:05pm Addthis Dr. Rhonda Jordan is an energy specialist at World Bank and our latest #WomenInSTEM video profile. | Video by Matty Greene. Erin R. Pierce Erin R. Pierce Former Digital Communications Specialist, Office of Public Affairs Matty Greene Matty Greene Former Videographer Earlier this year we launched #WomenInSTEM, a video series highlighting the accomplishments of

  2. Upper Bound on the First Star Formation History (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Upper Bound on the First Star Formation History Citation Details In-Document Search Title: Upper Bound on the First Star Formation History You are accessing a document from the ...

  3. Copy of Bound Original For Scanning

    Office of Legacy Management (LM)

    Copy of Bound Original For Scanning Document # 1\1\ i g -b DOE/El/-0005/6 Formerly Utilized IVIEWAEC Site! Remedial Action Progrhn, F@diilogical Survey of the Seaway Industrial Par Tonawanda, New Yor May 197 Final Repel Prepared f U.S. Department of Enerc Assistant Secretary for Environme Division of Environmental Control Technolo Washington, D.C. 205, uric Contract No. W-7405-ENG- - - - Available from: ' : -. National Technical Information Service (NTIS) U.S. Department of Comnerce 5285 Port

  4. Bound Neutrons Pave Way to Free Ones | Jefferson Lab

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

    Bound Neutrons Pave Way to Free Ones Bound Neutrons Pave Way to Free Ones Bound Neutrons Some experiments seem to show that the building blocks of protons and neutrons inside a nucleus are somehow different from that of free ones. Other experiments show they behave differently when they pair up: they move faster and frequently overlap. NEWPORT NEWS, VA, February 7, 2011 - A study of bound protons and neutrons conducted at the Department of Energy's Thomas Jefferson National Accelerator Facility

  5. Improved lower bound on the entropic uncertainty relation

    SciTech Connect (OSTI)

    Jafarpour, Mojtaba; Sabour, Abbass

    2011-09-15

    We present a lower bound on the entropic uncertainty relation for the distinguished measurements of two observables in a d-dimensional Hilbert space for d up to 5. This bound provides an improvement over the best one yet available. The feasibility of the obtained bound presenting an improvement for higher dimensions is also discussed.

  6. Applied Math PI Meet | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Applied Math PI Meet Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding Opportunities Advanced Scientific Computing Advisory Committee (ASCAC) Community Resources Featured Content ASCR Discovery ASCR Program Documents ASCR Workshops and Conferences Workshops & Conferences Archive DOE Simulations Summit Scientific Grand Challenges Workshop Series SciDAC Conferences HPC Operations Review and Best Practices Workshops

  7. DOE Applied Math Summit | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    DOE Applied Math Summit Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding Opportunities Advanced Scientific Computing Advisory Committee (ASCAC) Community Resources Featured Content ASCR Discovery ASCR Program Documents ASCR Workshops and Conferences Workshops & Conferences Archive DOE Simulations Summit Scientific Grand Challenges Workshop Series SciDAC Conferences HPC Operations Review and Best Practices Workshops

  8. Extremum seeking with bounded update rates

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

    Scheinker, Alexander; Krstić, Miroslav

    2013-11-16

    In this work, we present a form of extremum seeking (ES) in which the unknown function being minimized enters the system’s dynamics as the argument of a cosine or sine term, thereby guaranteeing known bounds on update rates and control efforts. We present general n-dimensional optimization and stabilization results as well as 2D vehicle control, with bounded velocity and control efforts. For application to autonomous vehicles, tracking a source in a GPS denied environment with unknown orientation, this ES approach allows for smooth heading angle actuation, with constant velocity, and in application to a unicycle-type vehicle results in control abilitymore » as if the vehicle is fully actuated. Our stability analysis is made possible by the classic results of Kurzweil, Jarnik, Sussmann, and Liu, regarding systems with highly oscillatory terms. In our stability analysis, we combine the averaging results with a semi-global practical stability result under small parametric perturbations developed by Moreau and Aeyels.« less

  9. Bounded extremum seeking with discontinuous dithers

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

    Scheinker, Alexander; Scheinker, David

    2016-03-21

    The analysis of discontinuous extremum seeking (ES) controllers, e.g. those applicable to digital systems, has historically been more complicated than that of continuous controllers. We establish a simple and general extension of a recently developed bounded form of ES to a general class of oscillatory functions, including functions discontinuous with respect to time, such as triangle or square waves with dead time. We establish our main results by combining a novel idea for oscillatory control with an extension of functional analytic techniques originally utilized by Kurzweil, Jarnik, Sussmann, and Liu in the late 80s and early 90s and recently studiedmore » by Durr et al. Lastly, we demonstrate the value of the result with an application to inverter switching control.« less

  10. Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile

    SciTech Connect (OSTI)

    Habibi, M.; Ghamari, F.

    2014-05-15

    The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

  11. Nonuniversal gaugino masses and muon<math display='inline'>g-2math>

    SciTech Connect (OSTI)

    Gogoladze, Ilia; Nasir, Fariha; Shafi, Qaisar; n, Cem Salih

    2014-08-11

    We consider two classes of supersymmetric models with nonuniversal gaugino masses at the grand unification scale MGUT in an attempt to resolve the apparent muon g-2 anomaly encountered in the Standard Model. We explore two distinct scenarios, one in which all gaugino masses have the same sign at MGUT, and a second case with opposite sign gaugino masses. The sfermion masses in both cases are assumed to be universal at MGUT. We exploit the nonuniversality among gaugino masses to realize large mass splitting between the colored and noncolored sfermions. Thus, the sleptons can have masses in the few hundred GeV range, whereas the colored sparticles turn out to be an order of magnitude or so heavier. In both models the resolution of the muon g-2 anomaly is compatible, among other things, with a 125126 GeV Higgs boson mass and the WMAP dark matter bounds.

  12. Small-Scale Structure of Spacetime: Bounds and Conjectures

    SciTech Connect (OSTI)

    Klinkhamer, F. R.

    2008-03-06

    This review consists of two parts. The first part establishes certain astrophysical bounds on the smoothness of classical spacetime.Some of the best bounds to date are based on the absence of vacuum Cherenkov radiation in ultrahigh-energy cosmic rays. The second part discusses possible implications of these bounds for the quantum structure of spacetime. One conjecture is that the fundamental length scale of quantum spacetime may be different from the Planck length.

  13. Organically bound tritium analysis in environmental samples

    SciTech Connect (OSTI)

    Baglan, N.; Cossonnet, C.; Fournier, M.; Momoshima, N.; Ansoborlo, E.

    2015-03-15

    Organically bound tritium (OBT) has become of increased interest within the last decade, with a focus on its behaviour and also its analysis, which are important to assess tritium distribution in the environment. In contrast, there are no certified reference materials and no standard analytical method through the international organization related to OBT. In order to resolve this issue, an OBT international working group was created in May 2012. Over 20 labs from around the world participated and submitted their results for the first intercomparison exercise results on potato (Sep 2013). The samples, specially-prepared potatoes, were provided in March 2013 to each participant. Technical information and results from this first exercise are discussed here for all the labs which have realised the five replicates necessary to allow a reliable statistical treatment. The results are encouraging as the increased number of participating labs did not degrade the observed dispersion of the results for a similar activity level. Therefore, the results do not seem to depend on the analytical procedure used. From this work an optimised procedure can start to be developed to deal with OBT analysis and will guide subsequent planned OBT trials by the international group.

  14. Bound Brook, New Jersey: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Bound Brook, New Jersey: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 40.5684363, -74.5384889 Show Map Loading map... "minzoom":false,"mappi...

  15. South Bound Brook, New Jersey: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    Bound Brook, New Jersey: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 40.5534364, -74.531544 Show Map Loading map... "minzoom":false,"mappin...

  16. UPPER BOUND ON THE FIRST STAR FORMATION HISTORY (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: UPPER BOUND ON THE FIRST STAR FORMATION HISTORY Our understanding of the nature of the extragalactic background light (EBL) has improved ...

  17. Structure of the Ebola virus glycoprotein bound to an antibody...

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

    Structure of the Ebola virus glycoprotein bound to an antibody from a human survivor ... viral surface glycoprotein in complex with a rare antibody derived from a human survivor. ...

  18. Structure of the human M2 muscarinic acetylcholine receptor bound...

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

    Structure of the human M2 muscarinic acetylcholine receptor bound to an antagonist Citation Details In-Document Search Title: Structure of the human M2 muscarinic acetylcholine ...

  19. New Math Captures Fluids in Unprecedented Detail | U.S. DOE Office of

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

    Science (SC) Highlights » 2016 » New Math Captures Fluids in Unprecedented Detail Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding Opportunities Advanced Scientific Computing Advisory Committee (ASCAC) Community Resources Contact Information Advanced Scientific Computing Research U.S. Department of Energy SC-21/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-7486 F: (301) 903-4846

  20. LANL gets young women involved in math and science at 31st Expanding Your

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

    Horizons Conference April 6 31st Expanding Your Horizons Conference LANL gets young women involved in math and science at 31st Expanding Your Horizons Conference April 6 The young women will participate in hands-on activities in such fields as astronomy, robotics, forensics, chemistry, and earth science. March 4, 2010 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering

  1. Two-photon bound state in self-focusing media

    SciTech Connect (OSTI)

    Chiao, R.Y.; Deutsch, I.H. ); Garrison, J.C. )

    1991-09-09

    We derive a two-photon bound-state solution to the problem of quantum propagation of light in Kerr-effect nonlinear media which classically would exhibit self-focusing and self-trapping. We propose an experiment to see this two-photon bound state.

  2. Bound states in a hyperbolic asymmetric double-well

    SciTech Connect (OSTI)

    Hartmann, R. R.

    2014-01-15

    We report a new class of hyperbolic asymmetric double-well whose bound state wavefunctions can be expressed in terms of confluent Heun functions. An analytic procedure is used to obtain the energy eigenvalues and the criterion for the potential to support bound states is discussed.

  3. Evaluation of American Indian Science and Engineering Society Intertribal Middle School Science and Math Bowl Project

    SciTech Connect (OSTI)

    AISES, None

    2013-09-25

    The American Indian Science and Engineering Society (AISES) has been funded under a U.S. Department of Energy (DOE) grant (Grant Award No. DE-SC0004058) to host an Intertribal Middle-School Science and Math Bowl (IMSSMB) comprised of teams made up of a majority of American Indian students from Bureau of Indian Education-funded schools and public schools. The intent of the AISES middle school science and math bowl is to increase participation of American Indian students at the DOE-sponsored National Science Bowl. Although national in its recruitment scope, the AISES Intertribal Science and Math Bowl is considered a “regional” science bowl, equivalent to the other 50 regional science bowls which are geographically limited to states. Most regional bowls do not have American Indian student teams competing, hence the AISES bowl is meant to encourage American Indian student teams to increase their science knowledge in order to participate at the national level. The AISES competition brings together teams from various American Indian communities across the nation. Each team is provided with funds for travel to and from the event, as well as for lodging and meals. In 2011 and 2012, there were 10 teams participating; in 2013, the number of teams participating doubled to 20. Each Science and Math Bowl team is comprised of four middle school — grades 6 through 8 — students, one alternate, and a teacher who serves as advisor and coach — although in at least two cases, the coach was not a teacher, but was the Indian Education Coordinator. Each team member must have at least a 3.0 GPA. Furthermore, the majority of students in each team must be comprised of American Indian, Alaska Native or Native Hawaiian students. Under the current DOE grant, AISES sponsored three annual middle school science bowl competitions over the years 2011, 2012 and 2013. The science and math bowls have been held in late March concurrently with the National American Indian Science and

  4. A field range bound for general single-field inflation

    SciTech Connect (OSTI)

    Baumann, Daniel; Green, Daniel E-mail: drgreen@ias.edu

    2012-05-01

    We explore the consequences of a detection of primordial tensor fluctuations for general single-field models of inflation. Using the effective theory of inflation, we propose a generalization of the Lyth bound that applies to models of inflation coupled to Einstein gravity. Our strongest bound applies to all single-field models with two-derivative kinetic terms for the scalar fluctuations and is always stronger than the corresponding bound for slow-roll models. This shows that non-trivial dynamics of the inflaton can't evade the Lyth bound. We also present a weaker, but more universal bound that holds when the Null Energy Condition (NEC) is satisfied at horizon crossing.

  5. Magnetocrystalline anisotropy in <math>UMn2Ge2math> and related Mn-based actinide ferromagnets

    SciTech Connect (OSTI)

    Parker, David S.; Ghimire, Nirmal; Singleton, John; Thompson, J. D.; Bauer, Eric D.; Baumbach, Ryan; Mandrus, David; Li, Ling; Singh, David J.

    2015-05-04

    We present magnetization isotherms in pulsed magnetic fields up to 62 Tesla, supported by first principles calculations, demonstrating a huge uniaxial magnetocrystalline anisotropy energy - approximately 20 MJ/m3 - in <math>UMn2Ge2math>. This large anisotropy results from the extremely strong spin-orbit coupling affecting the uranium 5 f electrons, which in the calculations exhibit a substantial orbital moment exceeding 2 μB. Finally, we also find from theoretical calculations that a number of isostructural Mn-actinide compounds are expected to have similarly large anisotropy.

  6. Culturally relevant science: An approach to math science education for Hispanics

    SciTech Connect (OSTI)

    Montellano, B.O. de

    1996-11-14

    This report describes later stages of a program to develop culturally relevant science and math programs for Hispanic students. Part of this effort was follow-up with 17 teachers who participated in early stages of the program. Response was not very good. Included with the report is a first draft effort for curriculum materials which could be used as is in such a teaching effort. Several of the participating teachers were invited to a writing workshop, where lesson plans were drafted, and critiqued and following rework are listed in this publication. Further work needs to be completed and is ongoing.

  7. #WomenInSTEM: Using Science & Math to Power the Globe

    SciTech Connect (OSTI)

    Jordan, Rhonda

    2014-05-27

    Growing up, Dr. Rhonda Jordan always enjoyed math and science. After completing her master's in electrical engineering at Columbia University she co-founded a startup in Tanzania that provides access to power for residents who are not connected to the electrical grid. This video is part of the Energy Department's #WomenInSTEM video series. At the Energy Department, we're committed to supporting a diverse talent pool of STEM innovators ready to address the challenges and opportunities of our growing clean energy economy.

  8. #WomenInSTEM: Using Science & Math to Power the Globe

    ScienceCinema (OSTI)

    Jordan, Rhonda

    2014-06-04

    Growing up, Dr. Rhonda Jordan always enjoyed math and science. After completing her master's in electrical engineering at Columbia University she co-founded a startup in Tanzania that provides access to power for residents who are not connected to the electrical grid. This video is part of the Energy Department's #WomenInSTEM video series. At the Energy Department, we're committed to supporting a diverse talent pool of STEM innovators ready to address the challenges and opportunities of our growing clean energy economy.

  9. SRS 'teach-ins' show why math and science are cool | National Nuclear

    National Nuclear Security Administration (NNSA)

    Security Administration | (NNSA) 'teach-ins' show why math and science are cool Thursday, March 13, 2014 - 4:00pm More than 40 engineers, scientists and technicians from the Savannah River Site recently brought creative science- and engineering-based demonstrations to more than 3,000 middle school students, captivating their minds with things like flying objects and robotic creatures to give them a broader understanding of the field of engineering. Over a two-week period, employees of SRS

  10. Bounding gauged skyrmion masses (Journal Article) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Bounding gauged skyrmion masses Citation Details In-Document ... OSTI Identifier: 1151557 Report Number(s): ANL-HEP-PR-04-89 DOE Contract Number: AC02-07CH11359 Resource Type: Journal ...

  11. Widget:BoundingCoordinatesHelper | Open Energy Information

    Open Energy Info (EERE)

    This widget creates an interactive Google map to assist with the input of bounding box coordinates. The map will output the NE and SW corners of a rectangular extent to two...

  12. Bounding the Pseudogap in Cuprate High-TC Superconductors (Technical...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Bounding the Pseudogap in Cuprate High-TC Superconductors Authors: McDonald, Ross David 1 ; Shehter, Arkady 1 ; Balakirev, Fedor F. ...

  13. Out of bounds additive manufacturing (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Out of bounds additive manufacturing Citation Details In-Document Search ... GrantContract Number: AC05-00OR22725 Type: Accepted Manuscript Journal Name: Advanced ...

  14. Upper Bound on the First Star Formation History (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Upper Bound on the First Star Formation History Citation Details ... Publication Date: 2014-11-20 OSTI Identifier: 1165908 Report Number(s): SLAC-PUB-16151 Journal ID: ISSN ...

  15. Upper Bound on the First Star Formation History (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Upper Bound on the First Star Formation History Citation Details ... Publication Date: 2014-01-09 OSTI Identifier: 1114151 Report Number(s): SLAC-PUB-15885 Journal ID: ISSN ...

  16. Structure of the Ebola Virus Glycoprotein Bound to an Antibody...

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

    Bound to an Antibody from a Human Survivor Print Ebolavirus, one of two members of the family of filoviruses, causes a severe hemorrhagic fever with 50-90% human mortality. ...

  17. AN INDIRECT SEARCH FOR WEAKLY INTERACTING MASSIVE PARTICLES IN THE SUN USING 3109.6 DAYS OF UPWARD-GOING MUONS IN SUPER-KAMIOKANDE

    SciTech Connect (OSTI)

    Tanaka, T.; Abe, K.; Hayato, Y.; Iida, T.; Kameda, J.; Koshio, Y.; Kouzuma, Y.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakayama, S.; Obayashi, Y.; Sekiya, H.; Shiozawa, M.; Suzuki, Y.; Takeda, A.; Takenaga, Y.; Ueno, K.; Ueshima, K.; Yamada, S.; Collaboration: Super-Kamiokande Collaboration; and others

    2011-12-01

    We present the result of an indirect search for high energy neutrinos from Weakly Interacting Massive Particle (WIMP) annihilation in the Sun using upward-going muon (upmu) events at Super-Kamiokande. Data sets from SKI-SKIII (3109.6 days) were used for the analysis. We looked for an excess of neutrino signal from the Sun as compared with the expected atmospheric neutrino background in three upmu categories: stopping, non-showering, and showering. No significant excess was observed. The 90% C.L. upper limits of upmu flux induced by WIMPs of 100 GeV c{sup -2} were 6.4 Multiplication-Sign 10{sup -15} cm{sup -2} s{sup -1} and 4.0 Multiplication-Sign 10{sup -15} cm{sup -2} s{sup -1} for the soft and hard annihilation channels, respectively. These limits correspond to upper limits of 4.5 Multiplication-Sign 10{sup -39} cm{sup -2} and 2.7 Multiplication-Sign 10{sup -40} cm{sup -2} for spin-dependent WIMP-nucleon scattering cross sections in the soft and hard annihilation channels, respectively.

  18. Symmetry-breaking instability of quadratic soliton bound states

    SciTech Connect (OSTI)

    Delque, Michaeel; Fanjoux, Gil; Maillotte, Herve; Kockaert, Pascal; Sylvestre, Thibaut; Haelterman, Marc

    2011-01-15

    We study both numerically and experimentally two-dimensional soliton bound states in quadratic media and demonstrate their symmetry-breaking instability. The experiment is performed in a potassium titanyl phosphate crystal in a type-II configuration. The bound state is generated by the copropagation of the antisymmetric fundamental beam locked in phase with the symmetrical second harmonic one. Experimental results are in good agreement with numerical simulations of the nonlinear wave equations.

  19. Bound Neutrons Pave Way to Free Ones | Jefferson Lab

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

    Bound Neutrons Pave Way to Free Ones Bound Neutrons Pave Way to Free Ones Unexpected Connection - Some experiments seem to show that the building blocks of protons and neutrons inside a nucleus are somehow different from that of free neutrons and protons. Other experiments show protons and neutrons behave differently when they pair up. A new study shows these two different lines of research are correlated, leading to information on the internal structure of free neutrons without the assistance

  20. Cosmological stability bound in massive gravity and bigravity

    SciTech Connect (OSTI)

    Fasiello, Matteo; Tolley, Andrew J. E-mail: andrew.j.tolley@case.edu

    2013-12-01

    We give a simple derivation of a cosmological bound on the graviton mass for spatially flat FRW solutions in massive gravity with an FRW reference metric and for bigravity theories. This bound comes from the requirement that the kinetic term of the helicity zero mode of the graviton is positive definite. The bound is dependent only on the parameters in the massive gravity potential and the Hubble expansion rate for the two metrics. We derive the decoupling limit of bigravity and FRW massive gravity, and use this to give an independent derivation of the cosmological bound. We recover our previous results that the tension between satisfying the Friedmann equation and the cosmological bound is sufficient to rule out all observationally relevant FRW solutions for massive gravity with an FRW reference metric. In contrast, in bigravity this tension is resolved due to different nature of the Vainshtein mechanism. We find that in bigravity theories there exists an FRW solution with late-time self-acceleration for which the kinetic terms for the helicity-2, helicity-1 and helicity-0 are generically nonzero and positive making this a compelling candidate for a model of cosmic acceleration. We confirm that the generalized bound is saturated for the candidate partially massless (bi)gravity theories but the existence of helicity-1/helicity-0 interactions implies the absence of the conjectured partially massless symmetry for both massive gravity and bigravity.

  1. Strong enhancement of <math>s> -wave superconductivity near a quantum critical point of <math>Ca3Ir4Sn13math>

    SciTech Connect (OSTI)

    Biswas, P. K.; Guguchia, Z.; Khasanov, R.; Chinotti, M.; Li, L.; Wang, Kefeng; Petrovic, C.; Morenzoni, E.

    2015-11-11

    We report microscopic studies by muon spin rotation/relaxation as a function of pressure of the <math>Ca3Ir4Sn13math> and Sr3Ir4Sn13 system displaying superconductivity and a structural phase transition associated with the formation of a charge density wave (CDW). Our findings show a strong enhancement of the superfluid density and a dramatic increase of the pairing strength above a pressure of ≈ 1.6 GPa giving direct evidence of the presence of a quantum critical point separating a superconducting phase coexisting with CDW from a pure superconducting phase. The superconducting order parameter in both phases has the same s-wave symmetry. In spite of the conventional phonon-mediated BCS character of the weakly correlated (Ca1-xSrx)3Ir4Sn13 system the dependence of the effective superfluid density on the critical temperature puts this compound in the “Uemura” plot close to unconventional superconductors. This system exemplifies that conventional BCS superconductors in the presence of competing orders or multi-band structure can also display characteristics of unconventional superconductors.

  2. V-156: Linux Kernel Array Bounds Checking Flaw Lets Local Users...

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

    6: Linux Kernel Array Bounds Checking Flaw Lets Local Users Gain Elevated Privileges V-156: Linux Kernel Array Bounds Checking Flaw Lets Local Users Gain Elevated Privileges May...

  3. Math Libraries

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

    Policies User Surveys NERSC Users Group Help Staff Blogs Request Repository Mailing List Need Help? Out-of-hours Status and Password help Call operations: 1-800-66-NERSC, option 1 ...

  4. Bounds on gravitational wave backgrounds from large distance clock comparisons

    SciTech Connect (OSTI)

    Reynaud, S.; Lamine, B.; Duchayne, L.; Wolf, P.; Jaekel, M.-T.

    2008-06-15

    Our space-time is filled with gravitational wave backgrounds that constitute a fluctuating environment created by astrophysical and cosmological sources. Bounds on these backgrounds are obtained from cosmological and astrophysical data but also by analysis of ranging and Doppler signals from distant spacecraft. We propose here a new way to set bounds on those backgrounds by performing clock comparisons between a ground clock and a remote spacecraft equipped with an ultrastable clock, rather than only ranging to an on-board transponder. This technique can then be optimized as a function of the signal to be measured and the dominant noise sources, leading to significant improvements on present bounds in a promising frequency range where different theoretical models are competing. We illustrate our approach using the SAGAS project which aims to fly an ultrastable optical clock in the outer solar system.

  5. Bioavailability of sediment-bound contaminants to marine organisms

    SciTech Connect (OSTI)

    Brown, B.; Neff, J.

    1993-09-01

    The bioavailability of sediment-bound contaminants to marine organisms indicates that there exists a potential for transfer of these contaminants through marine food webs to commercial fisheries products consumed by humans. However, there has been relatively little effort to combine and synthesize data on chemical/biological interactions between benthic animals and seagrasses and the sediments in which they reside on the one hand, and on the chemistry of bioaccumulation on the other. This report provides a conceptual basis for an approach to bioavailability and biomagnification of sediment-bound contaminants that reviews biological and chemical approaches.

  6. Closeness to spheres of hypersurfaces with normal curvature bounded below

    SciTech Connect (OSTI)

    Borisenko, A A; Drach, K D

    2013-11-30

    For aRiemannian manifold M{sup n+1} and acompact domain ??M{sup n+1} bounded by ahypersurface ?? with normal curvature bounded below, estimates are obtained in terms of the distance from O to ?? for the angle between the geodesic line joining afixed interior point O in ? to apoint on ?? and the outward normal to the surface. Estimates for the width of aspherical shell containing such ahypersurface are also presented. Bibliography: 9 titles.

  7. Towards flavored bound states beyond rainbows and ladders

    SciTech Connect (OSTI)

    El-Bennich, B.; Rojas, E.; Melo, J. P. B. C. de; Paracha, M. A.

    2014-11-11

    We give a snapshot of recent progress in solving the Dyson-Schwinger equation with a beyond rainbow-ladder ansatz for the dressed quark-gluon vertex which includes ghost contributions. We discuss the motivations for this approach with regard to heavy-flavored bound states and form factors and briefly describe future steps to be taken.

  8. PICO: An Object-Oriented Framework for Branch and Bound

    SciTech Connect (OSTI)

    ECKSTEIN,JONATHAN; HART,WILLIAM E.; PHILLIPS,CYNTHIA A.

    2000-12-01

    This report describes the design of PICO, a C++ framework for implementing general parallel branch-and-bound algorithms. The PICO framework provides a mechanism for the efficient implementation of a wide range of branch-and-bound methods on an equally wide range of parallel computing platforms. We first discuss the basic architecture of PICO, including the application class hierarchy and the package's serial and parallel layers. We next describe the design of the serial layer, and its central notion of manipulating subproblem states. Then, we discuss the design of the parallel layer, which includes flexible processor clustering and communication rates, various load balancing mechanisms, and a non-preemptive task scheduler running on each processor. We describe the application of the package to a branch-and-bound method for mixed integer programming, along with computational results on the ASCI Red massively parallel computer. Finally we describe the application of the branch-and-bound mixed-integer programming code to a resource constrained project scheduling problem for Pantex.

  9. On spectral perturbation caused by bounded variation of potential

    SciTech Connect (OSTI)

    Ismagilov, R S

    2014-01-31

    The harmonic oscillator operator is perturbed by an arbitrary bounded continuous term. This results in the perturbation of the spectrum. The map sending the first of these perturbations into the second is examined. Its approximation by a linear map is studied. Bibliography: 2 titles.

  10. Key management and encryption under the bounded storage model.

    SciTech Connect (OSTI)

    Draelos, Timothy John; Neumann, William Douglas; Lanzone, Andrew J.; Anderson, William Erik

    2005-11-01

    There are several engineering obstacles that need to be solved before key management and encryption under the bounded storage model can be realized. One of the critical obstacles hindering its adoption is the construction of a scheme that achieves reliable communication in the event that timing synchronization errors occur. One of the main accomplishments of this project was the development of a new scheme that solves this problem. We show in general that there exist message encoding techniques under the bounded storage model that provide an arbitrarily small probability of transmission error. We compute the maximum capacity of this channel using the unsynchronized key-expansion as side-channel information at the decoder and provide tight lower bounds for a particular class of key-expansion functions that are pseudo-invariant to timing errors. Using our results in combination with Dziembowski et al. [11] encryption scheme we can construct a scheme that solves the timing synchronization error problem. In addition to this work we conducted a detailed case study of current and future storage technologies. We analyzed the cost, capacity, and storage data rate of various technologies, so that precise security parameters can be developed for bounded storage encryption schemes. This will provide an invaluable tool for developing these schemes in practice.

  11. Evidence for a Bound H Dibaryon from Lattice QCD

    SciTech Connect (OSTI)

    Beane, S. R.; Chang, E.; Parreno, A.; Detmold, W.; Orginos, K.; Joo, B.; Lin, H. W.; Savage, M. J.; Luu, T. C.; Torok, A.; Walker-Loud, A.

    2011-04-22

    We present evidence for the existence of a bound H dibaryon, an I=0, J=0, s=-2 state with valence quark structure uuddss, at a pion mass of m{sub {pi}{approx}3}89 MeV. Using the results of lattice QCD calculations performed on four ensembles of anisotropic clover gauge-field configurations, with spatial extents of L{approx}2.0, 2.5, 3.0, and 3.9 fm at a spatial lattice spacing of b{sub s{approx}}0.123 fm, we find an H dibaryon bound by B{sub {infinity}}{sup H}=16.6{+-}2.1{+-}4.6 MeV at a pion mass of m{sub {pi}{approx}3}89 MeV.

  12. Revivals of zitterbewegung of a bound localized Dirac particle

    SciTech Connect (OSTI)

    Romera, Elvira

    2011-11-15

    In this paper a bound localized Dirac particle is shown to exhibit a revival of the zitterbewegung (ZB) oscillation amplitude. These revivals go beyond the known quasiclassical regenerations in which the ZB oscillation amplitude is decreasing from period to period. This phenomenon is studied in a Dirac oscillator and it is shown that it is possible to set up wave packets in which there is a regeneration of the initial ZB amplitude.

  13. Yttrium Dopants in Titania: not Structurally Incorporated but Bound at

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

    Surfaces Yttrium Dopants in Titania: not Structurally Incorporated but Bound at Surfaces Structurally incorporated impurities have been shown to have systematic effects on the rate of the thermally driven transformation in titania nanoparticles [1-4]. The anatase-to-rutile transformation is slowed when anatase nanoparticles are doped with a cation of valence > +4, but favored when the valence < +4. Based on these observations, Y3+ dopants should promote the anatase-to-rutile

  14. Angular-momentum nonclassicality by breaking classical bounds on statistics

    SciTech Connect (OSTI)

    Luis, Alfredo; Rivas, Angel

    2011-10-15

    We derive simple practical procedures revealing the quantum behavior of angular momentum variables by the violation of classical upper bounds on the statistics. Data analysis is minimum and definite conclusions are obtained without evaluation of moments, or any other more sophisticated procedures. These nonclassical tests are very general and independent of other typical quantum signatures of nonclassical behavior such as sub-Poissonian statistics, squeezing, or oscillatory statistics, being insensitive to the nonclassical behavior displayed by other variables.

  15. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print Tuesday, 24 January 2012 11:30 DNA replication is a critical...

  16. Universality of the Volume Bound in Slow-Roll Eternal Inflation...

    Office of Scientific and Technical Information (OSTI)

    Universality of the Volume Bound in Slow-Roll Eternal Inflation Citation Details In-Document Search Title: Universality of the Volume Bound in Slow-Roll Eternal Inflation You ...

  17. Structure of active [beta]-arrestin-1 bound to a G-protein-coupled...

    Office of Scientific and Technical Information (OSTI)

    bound to a G-protein-coupled receptor phosphopeptide Citation Details In-Document Search Title: Structure of active beta-arrestin-1 bound to a G-protein-coupled ...

  18. X ( 3915 ) as a D s D ¯ s bound state (Journal Article) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    X ( 3915 ) as a D s D s bound state Citation Details In-Document Search Title: X ( 3915 ) as a D s D s bound state Authors: Li, Xin ; Voloshin, M. B. Publication Date: ...

  19. X ( 3915 ) as a D s D ¯ s bound state (Journal Article) | DOE...

    Office of Scientific and Technical Information (OSTI)

    X ( 3915 ) as a D s D s bound state Prev Next Title: X ( 3915 ) as a D s D s bound state Authors: Li, Xin ; Voloshin, M. B. Publication Date: 2015-06-09 OSTI ...

  20. Optimal bounds for solving tridiagonal systems with preconditioning

    SciTech Connect (OSTI)

    Zellini, P. )

    1988-10-01

    Let (1) Tx=f be a linear tridiagonal system system of n equations in the unknown x/sub 1/, ..., x/sub n/. It is proved that 3n-2 (nonscalar) multiplications/divisions are necessary to solve (1) in a straight-line program excluding divisions by elements of f. This bound is optimal if the cost of preconditioning of T is not counted. Analogous results are obtained in case (i) T is bidiagonal and (ii) T and f are both centrosymmetric. The existence of parallel algorithms to solve (1) with preconditioning and with minimal multiplicative redundancy is also discussed.

  1. Quarkonium-nucleus bound states from lattice QCD

    SciTech Connect (OSTI)

    Beane, S.  R.; Chang, E.; Cohen, S.  D.; Detmold, W.; Lin, H. -W.; Orginos, K.; Parreño, A.; Savage, M.  J.

    2015-06-11

    Quarkonium-nucleus systems are composed of two interacting hadronic states without common valence quarks, which interact primarily through multi-gluon exchanges, realizing a color van der Waals force. We present lattice QCD calculations of the interactions of strange and charm quarkonia with light nuclei. Both the strangeonium-nucleus and charmonium-nucleus systems are found to be relatively deeply bound when the masses of the three light quarks are set equal to that of the physical strange quark. Extrapolation of these results to the physical light-quark masses suggests that the binding energy of charmonium to nuclear matter is B < 40 MeV.

  2. Evidence for a bound H-dibaryon using lattice QCD

    SciTech Connect (OSTI)

    Will Detmold

    2012-04-01

    The H-dibaryon, a J = 0 state with the valence quark content udsuds, has long been hypothesized to exist because of the attractive nature of color magnetic gluon exchange in the flavor- singlet channel. Using lattice QCD the NPLQCD collaboration have investigated this system and evidence is presented for the existence of a stable H-dibaryon, albeit at a quark mass somewhat larger than that in nature. This calculation is reviewed and combined with subsequent calculations by the HALQCD collaboration at the SU(3) flavor symmetric point to identify bounds on the H-dibaryon mass at the physical quark masses.

  3. Effect of transverse current on Andreev bound state

    SciTech Connect (OSTI)

    Takahashi, Y.; Hashimoto, Y.; Yun, D. H.; Kim, S. W.; Nakamura, T.; Iye, Y.; Katsumoto, S.

    2013-12-04

    In a superconductor-normal-superconductor (SNS) structure, the effect of transverse current across the normal part on the transport through Andreev bound states (ABSs) has been examined. Here a ballistic InAs two-dimensional electron system (2DES) is used as the N-layer to form ABSs. At the same time the 2DES has strong spin-orbit interaction, hence there should emerge the spin-Hall effect associated with the transverse current. We have observed strong reduction of characteristic oscillation in the conductance versus bias voltage, which may be attributed to spin polarization due to the spin-Hall effect.

  4. Hysteresis cycle in a turbulent, spherically bounded MHD dynamo model

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

    Hysteresis cycle in a turbulent, spherically bounded MHD dynamo model This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2009 New J. Phys. 11 013027 (http://iopscience.iop.org/1367-2630/11/1/013027) Download details: IP Address: 128.104.165.161 The article was downloaded on 14/12/2011 at 21:42 Please note that terms and conditions apply. View the table of contents for this issue, or go to the journal homepage for more Home Search Collections

  5. Fast concurrent array-based stacks, queues and deques using fetch-and-increment-bounded, fetch-and-decrement-bounded and store-on-twin synchronization primitives

    DOE Patents [OSTI]

    Chen, Dong; Gara, Alana; Heidelberger, Philip; Kumar, Sameer; Ohmacht, Martin; Steinmacher-Burow, Burkhard; Wisniewski, Robert

    2014-09-16

    Implementation primitives for concurrent array-based stacks, queues, double-ended queues (deques) and wrapped deques are provided. In one aspect, each element of the stack, queue, deque or wrapped deque data structure has its own ticket lock, allowing multiple threads to concurrently use multiple elements of the data structure and thus achieving high performance. In another aspect, new synchronization primitives FetchAndIncrementBounded (Counter, Bound) and FetchAndDecrementBounded (Counter, Bound) are implemented. These primitives can be implemented in hardware and thus promise a very fast throughput for queues, stacks and double-ended queues.

  6. Tunable Tensor Voting Improves Grouping of Membrane-Bound Macromolecules

    SciTech Connect (OSTI)

    Loss, Leandro A.; Bebis, George; Parvin, Bahram

    2009-04-15

    Membrane-bound macromolecules are responsible for structural support and mediation of cell-cell adhesion in tissues. Quantitative analysis of these macromolecules provides morphological indices for damage or loss of tissue, for example as a result of exogenous stimuli. From an optical point of view, a membrane signal may have nonuniform intensity around the cell boundary, be punctate or diffused, and may even be perceptual at certain locations along the boundary. In this paper, a method for the detection and grouping of punctate, diffuse curvilinear signals is proposed. Our work builds upon the tensor voting and the iterative voting frameworks to propose an efficient method to detect and refine perceptually interesting curvilinear structures in images. The novelty of our method lies on the idea of iteratively tuning the tensor voting fields, which allows the concentration of the votes only over areas of interest. We validate the utility of our system with synthetic and annotated real data. The effectiveness of the tunable tensor voting is demonstrated on complex phenotypic signals that are representative of membrane-bound macromolecular structures.

  7. Synthesis and application of new polymer bound catalysts

    SciTech Connect (OSTI)

    Fetterly, Brandon Michael

    2005-08-01

    Nitric acid has been shown to be a weak acid in acetonitrile. It is conceivable that a nitrate salt of a weakly Lewis acidic cation could furnish a ''naked'' nitrate anion as a basic catalyst in a variety of reactions in non-aqueous solvents. Such a nitrate salt could also be bound to a polymeric support via the cation, thereby allowing for reclamation and recycling of the nitrate ion. This subject is dealt with in Chapter 2, wherein my contributions consisted of performing all the reactions with the polymer supported catalyst and carrying out the experiments necessary to shed light on the reaction mechanisms. Chapter 3 contains a description of the structure and catalytic properties of an azidoproazaphosphatrane. This compound is an air-stable versatile catalyst that has proven useful not only homogeneously, but also when bound to a solid support. The synthesis of a polymer bound proazaphosphatrane containing a trivalent phosphorus is presented in Chapter 4. Such a compound has been sought after by our group for a number of years. Not only does the synthesis I have accomplished for it allow for easier separation of proazaphosphatrane catalysts from reaction mixtures, but recycling of the base is made much simpler. Proazaphosphatranes are useful homogeneous catalysts that activate atoms in other reagents, thus enhancing their reactivity. The next chapters deal with two such reactions with aldehydes and ketones, namely silylcyanations with trialkylsilylcyanides (Chapters 5 and 6) and reductions with poly(methylhydrosiloxane), in Chapter 7. In Chapter 5, Zhigang Wang performed the initial optimization and scoping of the reaction, while repetitions of the scoping experiments for reproducibility, determination of diastereomeric ratios, and experiments aimed at elucidating aspects of the mechanism were performed by me. The proazaphosphatrane coordinates to the silicon atom in both cases, thereby allowing the aforementioned reactions to proceed under much milder

  8. Reactivity of Metal Ions Bound to Water-Soluble Polymers

    SciTech Connect (OSTI)

    Sauer, N.N.; Watkins, J.G.; Lin, M.; Birnbaum, E.R.; Robison, T.W.; Smith, B.F.; Gohdes, J.W.; McDonald, J.G.

    1999-06-29

    The intent of this work is to determine the effectiveness of catalysts covalently bound to polymers and to understand the consequences of supporting the catalysts on catalyst efficiency and selectivity. Rhodium phosphine complexes with functional groups for coupling to polymers were prepared. These catalyst precursors were characterized using standard techniques including IR, NMR, and elemental analysis. Studies on the modified catalysts showed that they were still active hydrogenation catalysts. However, tethering of the catalysts to polyamines gave systems with low hydrogenation activity. Analogous biphasic systems were also explored. Phosphine ligands with a surfactant-like structure have been synthesized and used to prepare catalytically active complexes of palladium. The palladium complexes were utilized in Heck-type coupling reactions (e.g. coupling of iodobenzene and ethyl acrylate to produce ethyl cinnamate) under vigorously stirred biphasic reaction conditions, and were found to offer superior performance over a standard water-soluble palladium catalyst under analogous conditions.

  9. Bounds on cosmic strings from WMAP and SDSS

    SciTech Connect (OSTI)

    Wyman, Mark; Wasserman, Ira; Pogosian, Levon

    2005-07-15

    We find the constraints from Wilkinson microwave anisotropy probe (WMAP) and Sloan digital sky survey (SDSS) data on the fraction of cosmological fluctuations sourced by local cosmic strings using a Markov Chain Monte Carlo (MCMC) analysis. In addition to varying the usual 6 cosmological parameters and the string tension ({mu}), we also varied the amount of small-scale structure on the strings. Our results indicate that cosmic strings can account for up to 7 (14)% of the total power of the microwave anisotropy at 68 (95)% confidence level. The corresponding bound on the string mass per unit length, within our string model, is G{mu}<3.4(5)x10{sup -7} at 68 (95)% C.L. We also calculate the B-type polarization spectra sourced by cosmic strings and discuss the prospects of their detection.

  10. A complexity analysis of space-bounded learning algorithms for the constraint satisfaction problem

    SciTech Connect (OSTI)

    Bayardo, R.J. Jr.; Miranker, D.P.

    1996-12-31

    Learning during backtrack search is a space-intensive process that records information (such as additional constraints) in order to avoid redundant work. In this paper, we analyze the effects of polynomial-space-bounded learning on runtime complexity of backtrack search. One space-bounded learning scheme records only those constraints with limited size, and another records arbitrarily large constraints but deletes those that become irrelevant to the portion of the search space being explored. We find that relevance-bounded learning allows better runtime bounds than size-bounded learning on structurally restricted constraint satisfaction problems. Even when restricted to linear space, our relevance-bounded learning algorithm has runtime complexity near that of unrestricted (exponential space-consuming) learning schemes.

  11. Bound state calculations in QED and QCD using basis light-front

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

    quantization | Argonne Leadership Computing Facility Bound state calculations in QED and QCD using basis light-front quantization Authors: Pieter Maris, Paul Wiecki, Yang Li, Xingbo Zhao, James P. Vary In order to describe self-bound systems, one needs a nonperturbative approach. We discuss the relativistic bound state equations of QED and QCD formulated in Basis Light-Front Quantization. In this approach, the light-front direction is discretized, and two-dimensional harmonic oscillator

  12. Finite Energy and Bounded Attacks on Control System Sensor Signals

    SciTech Connect (OSTI)

    Djouadi, Seddik M; Melin, Alexander M; Ferragut, Erik M; Laska, Jason A

    2014-01-01

    Control system networks are increasingly being connected to enterprise level networks. These connections leave critical industrial controls systems vulnerable to cyber-attacks. Most of the effort in protecting these cyber-physical systems (CPS) has been in securing the networks using information security techniques and protection and reliability concerns at the control system level against random hardware and software failures. However, besides these failures the inability of information security techniques to protect against all intrusions means that the control system must be resilient to various signal attacks for which new analysis and detection methods need to be developed. In this paper, sensor signal attacks are analyzed for observer-based controlled systems. The threat surface for sensor signal attacks is subdivided into denial of service, finite energy, and bounded attacks. In particular, the error signals between states of attack free systems and systems subject to these attacks are quantified. Optimal sensor and actuator signal attacks for the finite and infinite horizon linear quadratic (LQ) control in terms of maximizing the corresponding cost functions are computed. The closed-loop system under optimal signal attacks are provided. Illustrative numerical examples are provided together with an application to a power network with distributed LQ controllers.

  13. Application of the bounds-analysis approach to arsenic and gallium...

    Office of Scientific and Technical Information (OSTI)

    Details In-Document Search This content will become publicly available on January 23, 2016 Title: Application of the bounds-analysis approach to arsenic and gallium antisite...

  14. Obtaining lower bounds from the progressive hedging algorithm for stochastic mixed-integer programs

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

    Gade, Dinakar; Hackebeil, Gabriel; Ryan, Sarah M.; Watson, Jean -Paul; Wets, Roger J.-B.; Woodruff, David L.

    2016-04-02

    We present a method for computing lower bounds in the progressive hedging algorithm (PHA) for two-stage and multi-stage stochastic mixed-integer programs. Computing lower bounds in the PHA allows one to assess the quality of the solutions generated by the algorithm contemporaneously. The lower bounds can be computed in any iteration of the algorithm by using dual prices that are calculated during execution of the standard PHA. In conclusion, we report computational results on stochastic unit commitment and stochastic server location problem instances, and explore the relationship between key PHA parameters and the quality of the resulting lower bounds.

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

    SciTech Connect (OSTI)

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

    2013-06-01

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

  16. UPPER BOUND ON THE FIRST STAR FORMATION HISTORY

    SciTech Connect (OSTI)

    Inoue, Yoshiyuki; Madejski, Grzegorz M.; Tanaka, Yasuyuki T.; Domnguez, Alberto

    2014-02-01

    Our understanding of the nature of the extragalactic background light (EBL) has improved with the recent development of gamma-ray observation techniques. An open subject in the context of the EBL is the reionization epoch, which is an important probe of the formation history of first stars, the so-called Population III (Pop III) stars. Although the mechanisms for the formation of PopIII stars are rather well understood on theoretical grounds, their formation history is still veiled in mystery because of their faintness. To shed light on this matter, we study jointly the gamma-ray opacity of distant objects and the reionization constraints from studies of intergalactic gas. By combining these studies, we obtain a sensitive upper bound on the PopIII star formation rate density of ?-dot {sub ?}(z)<0.01[(1+z)/(1+7.0)]{sup 3.4}(f{sub esc}/0.2){sup ?1}(C/3.0)M{sub ?}yr{sup ?1}Mpc{sup ?3} at z ? 7, where f {sub esc} and C are the escape fraction of ionizing photons from galaxies and the clumping factor of the intergalactic hydrogen gas. This limit is a ?10times tighter constraint compared with previous studies that take into account gamma-ray opacity constraints only. Even if we do not include the current gamma-ray constraints, the results do not change. This is because the detected gamma-ray sources are still at z ? 4.35 where the reionization has already finished.

  17. Scalability under a Power Bound using the GREMLINs Framework

    SciTech Connect (OSTI)

    Maiterth, Matthias

    2015-02-16

    With the move towards exascale, system and software developers will have to deal with issues of extreme parallelism. The system properties affected most by the increase in node and core count are the shared resources on node and across the system. The increase in parallelism leads to reduced memory and bandwidth when regarding individual cores. Since power is a limiting factor for supercomputers, and power is not fully utilized in current systems, overprovisioning compute resources is a viable approach to maximized power utilization. To maximize system performance in regard to these changing conditions, it is necessary to understand how resource restrictions impact performance and system behavior. For the purpose of understanding anticipated system properties the GREMLINs Framework was developed. The framework gives the opportunity to add power restrictions, hinder memory properties and introduce faults to study resilience, among others. These features give the opportunity to use current petascale technology to study problems system designers and software developers will have to face when moving towards exascale and beyond. This work describes the initial release of the GREMLINs Framework, developed for this work, and shows how it can be used to study the scaling behavior of proxy applications. These proxy applications represent a selection of HPC workloads important to the scientific community. The proxy applications studied are AMG2013, an algebraic multi-grid linear system solver, CoMD, a classical molecular dynamics proxy application and NEKBONE, an application that uses a high order spectral element method to solve the Navier-Stokes equations. The main interest of these studies lies in analysis regarding their power behavior at scale under a power bound. These findings show how the GREMLINs Framework can help systems and software designers to attain better application performance and can also be used as basis for CPU power balancing tools to use power more

  18. Enhancements of branch and bound methods for the maximal constraint satisfaction problem

    SciTech Connect (OSTI)

    Wallace, R.J.

    1996-12-31

    Two methods are described for enhancing performance of branch and bound methods for overconstrained CSPs. These methods improve either the upper or lower bound, respectively, during search, so the two can be combined. Upper bounds are improved by using heuristic repair methods before search to find a good solution quickly, whose cost is used as the initial upper bound. The method for improving lower bounds is an extension of directed arc consistency preprocessing, used in conjunction with forward checking. After computing directed arc consistency counts, inferred counts are computed for all values based on minimum counts for values of adjacent variables that are later in the search order. This inference process can be iterated, so that counts are cascaded from the end to the beginning of the search order, to augment the initial counts. Improvements in time and effort are demonstrated for both techniques using random problems.

  19. Bounding Radionuclide Inventory and Accident Consequence Calculation for the 1L Target

    SciTech Connect (OSTI)

    Kelsey, Charles T. IV

    2011-01-01

    A bounding radionuclide inventory for the tungsten of the Los Alamos Neutron Science Center (LANSCE) IL Target is calculated. Based on the bounding inventory, the dose resulting from the maximum credible incident (MCI) is calculated for the maximally exposed offsite individual (MEOl). The design basis accident involves tungsten target oxidation following a loss of cooling accident. Also calculated for the bounding radionuclide inventory is the ratio to the LANSCE inventory threshold for purposes of inventory control as described in the target inventory control policy. A bounding radionuclide inventory calculation for the lL Target was completed using the MCNPX and CINDER'90 codes. Continuous beam delivery at 200 {micro}A to 2500 mA{center_dot}h was assumed. The total calculated activity following this irradiation period is 205,000 Ci. The dose to the MEOI from the MCI is 213 mrem for the bounding inventory. The LANSCE inventory control threshold ratio is 132.

  20. Identifying and bounding uncertainties in nuclear reactor thermal power calculations

    SciTech Connect (OSTI)

    Phillips, J.; Hauser, E.; Estrada, H.

    2012-07-01

    decreasing the probability of significant over-power events. This paper will examine the basic elements involved in calculation of thermal power using ultrasonic transit-time technology and will discuss the criteria for bounding uncertainties associated with each element in order to achieve reactor thermal power calculations to within 0.3% to 0.4%. (authors)

  1. New bounded skew central difference scheme. Part 1: Formulation and testing

    SciTech Connect (OSTI)

    Moukalled, F.; Darwish, M.

    1997-01-01

    The skew central difference scheme is combined with the normalized variable formulation to yield a new bounded skew central difference scheme. The newly developed scheme is tested and compared with the upwind scheme, the bounded skew upwind scheme, and the high-resolution SMART scheme by solving four problems: (1) pure convection of a step profile in an oblique velocity field; (2) sudden expansion of an oblique flow field in a rectangular cavity; (3) driven flow in a skew cavity; and (4) gradual expansion in an axisymmetric, nonorthogonal channel. Results generated reveal the new scheme to be bounded and to be the most accurate among those investigated.

  2. Dependence in probabilistic modeling, Dempster-Shafer theory, and probability bounds analysis.

    SciTech Connect (OSTI)

    Oberkampf, William Louis; Tucker, W. Troy; Zhang, Jianzhong; Ginzburg, Lev; Berleant, Daniel J.; Ferson, Scott; Hajagos, Janos; Nelsen, Roger B.

    2004-10-01

    This report summarizes methods to incorporate information (or lack of information) about inter-variable dependence into risk assessments that use Dempster-Shafer theory or probability bounds analysis to address epistemic and aleatory uncertainty. The report reviews techniques for simulating correlated variates for a given correlation measure and dependence model, computation of bounds on distribution functions under a specified dependence model, formulation of parametric and empirical dependence models, and bounding approaches that can be used when information about the intervariable dependence is incomplete. The report also reviews several of the most pervasive and dangerous myths among risk analysts about dependence in probabilistic models.

  3. A 1.3-Å Structure of Zinc-bound N-terminal Domain of Calmodulin...

    Office of Scientific and Technical Information (OSTI)

    Ion-binding Step Citation Details In-Document Search Title: A 1.3- Structure of Zinc-bound N-terminal Domain of Calmodulin Elucidates Potential Early Ion-binding Step Authors: ...

  4. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print DNA replication is a critical step in the life of all organisms, insuring that each new cell gets an accurate copy of...

  5. Universality of the Volume Bound in Slow-Roll Eternal Inflation...

    Office of Scientific and Technical Information (OSTI)

    It has recently been shown that in single field slow-roll inflation the total volume cannot grow by a factor larger than esup Ssub dS2 without becoming infinite. The bound is ...

  6. The New Face of Protein-bound Copper: The Type Zero Copper Site

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

    The New Face of Protein-bound Copper: The Type Zero Copper Site Nature adapts copper ions to a multitude of tasks, yet in doing so forces the metal into only a few different ...

  7. Verifying the error bound of numerical computation implemented in computer systems

    DOE Patents [OSTI]

    Sawada, Jun

    2013-03-12

    A verification tool receives a finite precision definition for an approximation of an infinite precision numerical function implemented in a processor in the form of a polynomial of bounded functions. The verification tool receives a domain for verifying outputs of segments associated with the infinite precision numerical function. The verification tool splits the domain into at least two segments, wherein each segment is non-overlapping with any other segment and converts, for each segment, a polynomial of bounded functions for the segment to a simplified formula comprising a polynomial, an inequality, and a constant for a selected segment. The verification tool calculates upper bounds of the polynomial for the at least two segments, beginning with the selected segment and reports the segments that violate a bounding condition.

  8. Ultrahigh-energy cosmic-ray bounds on nonbirefringent modified Maxwell theory

    SciTech Connect (OSTI)

    Klinkhamer, F. R.; Risse, M.

    2008-01-01

    A particularly simple Lorentz-violating modification of the Maxwell theory of photons maintains gauge invariance, CPT, and renormalization. This modified Maxwell theory, coupled to standard Dirac particles, involves 19 dimensionless 'deformation parameters'. Ten of these parameters lead to birefringence and are already tightly constrained by astrophysics. New bounds on the remaining nine nonbirefringent parameters can be obtained from the absence of vacuum Cherenkov radiation for ultrahigh-energy cosmic rays (UHECRs). Using selected UHECR events recorded at the Pierre Auger Observatory and assigning pseudorandom directions (i.e., assuming large-scale isotropy), Cherenkov bounds are found at the 10{sup -18} level, which improve considerably upon current laboratory bounds. Future UHECR observations may reduce these Cherenkov bounds to the 10{sup -23} level.

  9. Theory and Modeling of Weakly Bound/Physisorbed Materials for Hydrogen Storage

    Broader source: Energy.gov [DOE]

    Presentation on the Theory and Modeling of Weakly Bound/Physisorbed Materials for Hydrogen Storage given at the DOE Theory Focus Session on Hydrogen Storage Materials on May 18, 2006.

  10. Fano-type coupling of a bound paramagnetic state with 2D continuum

    SciTech Connect (OSTI)

    Rozhansky, I. V.; Averkiev, N. S.; Lhderanta, E.

    2013-12-04

    We analyze an effect of a bound impurity state located at a tunnel distance from a quantum well (QW). The study is focused on the resonance case when the bound state energy lies within the continuum of the QW states. Using the developed theory we calculate spin polarization of 2D holes induced by paramagnetic (Mn) delta-layer in the vicinity of the QW and indirect exchange interaction between two impurities located at a tunnel distance from electron gas.

  11. A lower bound for routing on a completely connected optical communication parallel computer

    SciTech Connect (OSTI)

    Goldberg, L.A.; Jerrum, M.; MacKenzie, P.D.

    1993-08-03

    The task of routing a 2-relation on an n-processor completely connected optical communication parallel computer (OCPC) is considered. A lower bound is presented that applies to any randomized distributed algorithm for this task: specifically, it is shown that the expected number of steps required to route a 2-relation is {Omega}({radical} log log n) in the worst case. For comparison, the best upper bound known is O(log log n).

  12. Bounding the Higgs Width Through Interferometry (Journal Article) | SciTech

    Office of Scientific and Technical Information (OSTI)

    Connect Journal Article: Bounding the Higgs Width Through Interferometry Citation Details In-Document Search Title: Bounding the Higgs Width Through Interferometry Authors: Dixon, Lance J. ; Li, Ye ; /SLAC Publication Date: 2013-05-24 OSTI Identifier: 1080221 Report Number(s): SLAC-PUB-15463 arXiv:1305.3854 DOE Contract Number: AC02-76SF00515 Resource Type: Journal Article Resource Relation: Journal Name: Submitted to Physical Review Letters Research Org: SLAC National Accelerator Laboratory

  13. Crystal structure of the[mu]-opioid receptor bound to a morphinan

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

    antagonist (Journal Article) | SciTech Connect Crystal structure of the[mu]-opioid receptor bound to a morphinan antagonist Citation Details In-Document Search Title: Crystal structure of the[mu]-opioid receptor bound to a morphinan antagonist Opium is one of the world's oldest drugs, and its derivatives morphine and codeine are among the most used clinical drugs to relieve severe pain. These prototypical opioids produce analgesia as well as many undesirable side effects (sedation, apnoea

  14. TUNABLE TENSOR VOTING FOR REGULARIZING PUNCTATE PATTERNS OFMEMBRANE-BOUND PROTEIN SIGNALS

    SciTech Connect (OSTI)

    Loss, Leandro; Bebis, George; Parvin, Bahram

    2009-04-29

    Membrane-bound protein, expressed in the basal-lateral region, is heterogeneous and an important endpoint for understanding biological processes. At the optical resolution, membrane-bound protein can be visualized as being diffused (e.g., E-cadherin), punctate (e.g., connexin), or simultaneously diffused and punctate as a result of sample preparation or conditioning. Furthermore, there is a significant amount of heterogeneity as a result of technical and biological variations. This paper aims at enhancing membrane-bound proteins that are expressed between epithelial cells so that quantitative analysis can be enabled on a cell-by-cell basis. We propose a method to detect and enhance membrane-bound protein signal from noisy images. More precisely, we build upon the tensor voting framework in order to produce an efficient method to detect and refine perceptually interesting linear structures in images. The novelty of the proposed method is in its iterative tuning of the tensor voting fields, which allows the concentration of the votes only over areas of interest. The method is shown to produce high quality enhancements of membrane-bound protein signals with combined punctate and diffused characteristics. Experimental results demonstrate the benefits of using tunable tensor voting for enhancing and differentiating cell-cell adhesion mediated by integral cell membrane protein.

  15. Bound free electron-positron pair production accompanied by giant dipole resonances

    SciTech Connect (OSTI)

    Senguel, M. Y.; Gueclue, M. C.

    2011-01-15

    At the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), for example, virtual photons produce many particles. At small impact parameters where the colliding nuclei make peripheral collisions, photon fluxes are very large and these are responsible for the multiple photonuclear interactions. Free pair productions, bound free pair productions, and nuclear Coulomb excitations are important examples of such interactions, and these processes play important roles in the beam luminosity at RHIC and LHC. Here we obtained the impact parameter dependence of bound free pair production cross sections and by using this probability we obtained bound free electron-positron pair production with nuclear breakup for heavy ion collisions at RHIC and LHC. We also compared our results to the other calculations.

  16. Bound-state formation for thermal relic dark matter and unitarity

    SciTech Connect (OSTI)

    Harling, Benedict von; Petraki, Kalliopi E-mail: kpetraki@nikhef.nl

    2014-12-01

    We show that the relic abundance of thermal dark matter annihilating via a long-range interaction, is significantly affected by the formation and decay of dark matter bound states in the early universe, if the dark matter mass is above a few TeV . We determine the coupling required to obtain the observed dark matter density, taking into account both the direct 2-to-2 annihilations and the formation of bound states, and provide an analytical fit. We argue that the unitarity limit on the inelastic cross-section is realized only if dark matter annihilates via a long-range interaction, and we determine the upper bound on the mass of thermal-relic dark matter to be about 197 (139) TeV for (non)-self-conjugate dark matter.

  17. Minimal time trajectories for two-level quantum systems with two bounded controls

    SciTech Connect (OSTI)

    Boscain, Ugo; Grnberg, Fredrik; Long, Ruixing; Rabitz, Herschel

    2014-06-15

    In this paper we consider the minimum time population transfer problem for a two level quantum system driven by two external fields with bounded amplitude. The controls are modeled as real functions and we do not use the Rotating Wave Approximation. After projection on the Bloch sphere, we treat the time-optimal control problem with techniques of optimal synthesis on 2D manifolds. Based on the Pontryagin Maximum Principle, we characterize a restricted set of candidate optimal trajectories. Properties on this set, crucial for complete optimal synthesis, are illustrated by numerical simulations. Furthermore, when the two controls have the same bound and this bound is small with respect to the difference of the two energy levels, we get a complete optimal synthesis up to a small neighborhood of the antipodal point of the initial condition.

  18. New bounding and decomposition approaches for MILP investment problems: Multi-area transmission and generation planning under policy constraints

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

    Munoz, F. D.; Hobbs, B. F.; Watson, J. -P.

    2016-02-01

    A novel two-phase bounding and decomposition approach to compute optimal and near-optimal solutions to large-scale mixed-integer investment planning problems is proposed and it considers a large number of operating subproblems, each of which is a convex optimization. Our motivating application is the planning of power transmission and generation in which policy constraints are designed to incentivize high amounts of intermittent generation in electric power systems. The bounding phase exploits Jensen’s inequality to define a lower bound, which we extend to stochastic programs that use expected-value constraints to enforce policy objectives. The decomposition phase, in which the bounds are tightened, improvesmore » upon the standard Benders’ algorithm by accelerating the convergence of the bounds. The lower bound is tightened by using a Jensen’s inequality-based approach to introduce an auxiliary lower bound into the Benders master problem. Upper bounds for both phases are computed using a sub-sampling approach executed on a parallel computer system. Numerical results show that only the bounding phase is necessary if loose optimality gaps are acceptable. But, the decomposition phase is required to attain optimality gaps. Moreover, use of both phases performs better, in terms of convergence speed, than attempting to solve the problem using just the bounding phase or regular Benders decomposition separately.« less

  19. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print Tuesday, 24 January 2012 11:30 DNA replication is a critical step in the life of all organisms, insuring that each new cell gets an accurate copy of the genome. Among the legions of proteins required to do this work, the DNA-slicing "flap endonuclease" FEN1 plays a key role. Much of FEN1's structure was solved previously, but the DNA-free structure failed to expose

  20. Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human

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

    Survivor Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human Survivor Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human Survivor Print Wednesday, 26 November 2008 00:00 Ebolavirus, one of two members of the family of filoviruses, causes a severe hemorrhagic fever with 50-90% human mortality. That no vaccines or treatments are yet available combined with the frequent re-emergence of the virus, its high prevalence among wildlife, and ease of

  1. Using SU(3) relations to bound the CP asymmetries in B{yields}KKK decays

    SciTech Connect (OSTI)

    Engelhard, Guy; Raz, Guy

    2005-12-01

    We consider three-body {delta}s=1 B{yields}f decays with f=KKK. The deviations of -{eta}{sub f}S{sub f} from S{sub {psi}}{sub K{sub S}} and of C{sub f} from zero can be bounded using the approximate SU(3) flavor symmetry of the strong interactions and branching ratios of various {delta}s=0 modes. We present the most promising SU(3) amplitude relations that can be used to obtain these bounds.

  2. Attracting students and professionals into math, science, and technology education at the elementary and middle grades: Final report, September 1, 1992--February 28, 1994

    SciTech Connect (OSTI)

    Flick, L.B.

    1995-12-31

    This report describes the progress of a project to encourage students and professionals to participate in math, science, and technology education at the elementary and middle grades. The topics of the report include documenting activities and procedures for the purposes of evaluation and dissemination of descriptive information, generating case studies of the students going through this program to provide research and evaluation data on the process of attracting technically qualified people into elementary and middle school teaching, establishing a program of mentoring between scientists, engineers, and mathematicians and prospective teachers in the program, and establishing a program of mentoring between master teachers in area schools and prospective teachers.

  3. Semiclassical and quantum field theoretic bounds for traversable Lorentzian stringy wormholes

    SciTech Connect (OSTI)

    Nandi, Kamal Kanti; Zhang Yuanzhong; Kumar, K.B. Vijaya

    2004-09-15

    A lower bound on the size of a Lorentzian wormhole can be obtained by semiclassically introducing the Planck cutoff on the magnitude of tidal forces (Horowitz-Ross constraint). Also, an upper bound is provided by the quantum field theoretic constraint in the form of the Ford-Roman Quantum Inequality for massless minimally coupled scalar fields. To date, however, exact static solutions belonging to this scalar field theory have not been worked out to verify these bounds. To fill this gap, we examine the wormhole features of two examples from the Einstein frame description of the vacuum low energy string theory in four dimensions which is the same as the minimally coupled scalar field theory. Analyses in this paper support the conclusion of Ford and Roman that wormholes in this theory can have sizes that are indeed only a few order of magnitudes larger than the Planck scale. It is shown that the two types of bounds are also compatible. In the process, we point out a 'wormhole' analog of naked black holes.

  4. Tools for model-independent bounds in direct dark matter searches

    SciTech Connect (OSTI)

    Cirelli, Marco

    2013-10-01

    We discuss a framework (based on non-relativistic operators) and a self-contained set of numerical tools to derive the bounds from some current direct detection experiments on virtually any arbitrary model of Dark Matter elastically scattering on nuclei.

  5. Bounding the Higgs width at the LHC: complementary results from H→WW

    SciTech Connect (OSTI)

    Campbell, John M.; Ellis, R. Keith; Williams, Ciaran

    2014-03-01

    We investigate the potential of the process gg → H→ WW to provide bounds on the Higgs width. Recent studies using off-shell H→ ZZ events have shown that Run 1 LHC data can constrain the Higgs width, $\\Gamma_H < (25-45) \\Gamma_{H}^{\\rm SM}$. Using 20 fb-1 of 8 TeV ATLAS data, we estimate a bound on the Higgs boson width from the WW channel between $\\Gamma_H < (100-500) \\Gamma_H^{SM}$. The large spread in limits is due to the range of cuts applied in the existing experimental analysis. The stricter cuts designed to search for the on-shell Higgs boson limit the potential number of off-shell events, weakening the constraints. As some of the cuts are lifted the bounds improve. We show that there is potential in the high transverse mass region to produce upper bounds of the order of $(25-50) \\Gamma_H^{SM}$, depending strongly on the level of systematic uncertainty that can be obtained. Thus, if these systematics can be controlled, a constraint on the Higgs boson width from the H → WW$ decay mode can complement a corresponding limit from H → ZZ.

  6. Some problems in sequencing and scheduling utilizing branch and bound algorithms

    SciTech Connect (OSTI)

    Gim, B.

    1988-01-01

    This dissertation deals with branch and bound algorithms which are applied to the two-machine flow-shop problem with sparse precedence constraints and the optimal sequencing and scheduling of multiple feedstocks in a batch-type digester problem. The problem studied here is to find a schedule which minimizes the maximum flow time with the requirement that the schedule does not violate a set of sparse precedence constraints. This research provides a branch and bound algorithm which employs a lower bounding rule and is based on an adjustment of the sequence obtained by applying Johnson's algorithm. It is demonstrated that this lower bounding procedure in conjunction with Kurisu's branching rule is effective for the sparse precedence constraints problem case. Biomass to methane production systems have the potential of supplying 25% of the national gas demand. The optimal operation of a batch digester system requires the sequencing and scheduling of all batches from multiple feedstocks during a fixed time horizon. A significant characteristic of these systems is that the feedstock decays in storage before use in the digester system. The operational problem is to determine the time to allocate to each batch of several feedstocks and then sequence the individual batches so as to maximize biogas production for a single batch type digester over a fixed planning horizon. This research provides a branch and bound algorithm for sequencing and a two-step hierarchical dynamic programming procedure for time allocation scheduling. An efficient heuristic algorithm is developed for large problems and demonstrated to yield excellent results.

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

    SciTech Connect (OSTI)

    Berryman, J G

    2004-10-07

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

  8. Energy dependence of the optical potential of weakly and tightly bound nuclei as projectiles on a medium-mass target

    SciTech Connect (OSTI)

    Figueira, J. M.; Arazi, A.; Carnelli, P.; Heimann, D. Martinez; Negri, A. E.; Pacheco, A. J.; Niello, J. O. Fernandez; Capurro, O. A.; Fimiani, L.; Marti, G. V.; Lubian, J.; Monteiro, D. S.; Gomes, P. R. S.

    2010-02-15

    Angular distributions for the elastic scattering of the weakly bound {sup 6,7}Li+{sup 144}Sm systems were measured with high accuracy at bombarding energies from 85% up to 170% of the Coulomb barrier. An optical model analysis was performed, and the relevant parameters of the real and imaginary parts of the optical potential were extracted. The results are compared with those previously published for the tightly bound {sup 12}C+{sup 144}Sm and {sup 16}O+{sup 144}Sm systems. The usual threshold anomaly observed in the behavior of the potential of tightly bound systems was not observed for either weakly bound system. This absence is attributed to the repulsion due to breakup coupling which cancels the attraction arising from couplings with bound channels.

  9. Propagation of surface waves on a semi-bounded quantum magnetized collisional plasma

    SciTech Connect (OSTI)

    Niknam, A. R.; Taheri Boroujeni, S.; Khorashadizadeh, S. M.

    2013-12-15

    The propagation of surface waves on a semi-bounded quantum plasma in the presence of the external magnetic field and collisional effects is investigated by using quantum magnetohydrodynamics model. A general analytical expression for the dispersion relation of surface waves is obtained by considering the boundary conditions. It is shown that, in some special cases, the obtained dispersion relation reduces to the results reported in previous works. It is also indicated that the quantum, external magnetic field and collisional effects can facilitate the propagation of surface waves on a semi-bounded plasma. In addition, it is found that the growth rate of the surface wave instability is enhanced by increasing the collision frequency and plasmonic parameter.

  10. Stable and 'bounded excursion' gravastars, and black holes in Einstein's theory of gravity

    SciTech Connect (OSTI)

    Rocha, P; Da Silva, M F A; Wang, Anzhong; Chan, R E-mail: chan@on.br E-mail: anzhong_wang@baylor.edu

    2008-11-15

    Dynamical models of prototype gravastars are constructed and studied. The models are the Visser-Wiltshire three-layer gravastars, in which an infinitely thin spherical shell of a perfect fluid with the equation of state p = (1-{gamma}){sigma} divides the whole spacetime into two regions, where the internal region is de Sitter, and the external one is Schwarzschild. When {gamma}<1 and {Lambda}{ne}0, it is found that in some cases the models represent stable gravastars, and in some cases they represent 'bounded excursion' stable gravastars, where the thin shell is oscillating between two finite radii, while in some other cases they collapse until the formation of black holes occurs. However, when {gamma}{>=}1, even with {Lambda}{ne}0, only black holes are found. In the phase space, the region for both stable gravastars and 'bounded excursion' gravastars is very small in comparison to that for black holes, although it is not completely empty.

  11. Preliminary Results on the Experimental Investigation of the Structure Functions of Bound Nucleons

    SciTech Connect (OSTI)

    Bodek, Arie

    2015-09-01

    We present preliminary results on an experimental study of the nuclear modification of the longitudinal (σL) and transverse (σT) structure functions of nucleons bound in nuclear targets. The origin of these modifications (commonly referred as as the EMC effect) is not fully understood. Our measurements of R= σLT for nuclei (RA) and for deuterium (RD) indicate that nuclear modifications of the structure functions of bound nucleons are different for the longitudinal and transverse structure functions, and that contrary to expectation from several theoretical models, RA < RD.

  12. On lower bounds for possible blow-up solutions to the periodic Navier-Stokes equation

    SciTech Connect (OSTI)

    Cortissoz, Jean C. Montero, Julio A. Pinilla, Carlos E.

    2014-03-15

    We show a new lower bound on the H{sup .3/2} (T{sup 3}) norm of a possible blow-up solution to the Navier-Stokes equation, and also comment on the extension of this result to the whole space. This estimate can be seen as a natural limiting result for Leray's blow-up estimates in L{sup p}(R{sup 3}), 3 < p < ?. We also show a lower bound on the blow-up rate of a possible blow-up solution of the Navier-Stokes equation in H{sup .5/2} (T{sup 3}), and give the corresponding extension to the case of the whole space.

  13. Sensors closeness test based on an improved [0, 1] bounded Mahalanobis distance Δ{sup 2}

    SciTech Connect (OSTI)

    Masnan, Maz Jamilah; Mahat, Nor Idayu; Shakaff, Ali Yeon Md Abdullah, Abu Hassan

    2015-12-11

    Mahalanobis distance Δ{sup 2} values are commonly in the range of 0 to +∞ where higher values represent greater distance between class means or points. The increase in Mahalanobis distance is unbounded as the distance multiply. To certain extend, the unbounded distance values pose difficulties in the evaluation and decision for instance in the sensors closeness test. This paper proposes an approach to [0, 1] bounded Mahalanobis distance Δ{sup 2} that enable researcher to easily perform sensors closeness test. The experimental data of four different types of rice based on three different electronic nose sensors namely InSniff, PEN3, and Cyranose320 were analyzed and sensor closeness test seems successfully performed within the [0, 1] bound.

  14. Entropic uncertainty relations and locking: Tight bounds for mutually unbiased bases

    SciTech Connect (OSTI)

    Ballester, Manuel A.; Wehner, Stephanie

    2007-02-15

    We prove tight entropic uncertainty relations for a large number of mutually unbiased measurements. In particular, we show that a bound derived from the result by Maassen and Uffink [Phys. Rev. Lett. 60, 1103 (1988)] for two such measurements can in fact be tight for up to {radical}(d) measurements in mutually unbiased bases. We then show that using more mutually unbiased bases does not always lead to a better locking effect. We prove that the optimal bound for the accessible information using up to {radical}(d) specific mutually unbiased bases is log d/2, which is the same as can be achieved by using only two bases. Our result indicates that merely using mutually unbiased bases is not sufficient to achieve a strong locking effect and we need to look for additional properties.

  15. Fast multiscale Gaussian beam methods for wave equations in bounded convex domains

    SciTech Connect (OSTI)

    Bao, Gang; Department of Mathematics, Michigan State University, East Lansing, MI 48824 ; Lai, Jun; Qian, Jianliang

    2014-03-15

    Motivated by fast multiscale Gaussian wavepacket transforms and multiscale Gaussian beam methods which were originally designed for pure initial-value problems of wave equations, we develop fast multiscale Gaussian beam methods for initial boundary value problems of wave equations in bounded convex domains in the high frequency regime. To compute the wave propagation in bounded convex domains, we have to take into account reflecting multiscale Gaussian beams, which are accomplished by enforcing reflecting boundary conditions during beam propagation and carrying out suitable reflecting beam summation. To propagate multiscale beams efficiently, we prove that the ratio of the squared magnitude of beam amplitude and the beam width is roughly conserved, and accordingly we propose an effective indicator to identify significant beams. We also prove that the resulting multiscale Gaussian beam methods converge asymptotically. Numerical examples demonstrate the accuracy and efficiency of the method.

  16. Bound states for multiple Dirac-? wells in space-fractional quantum mechanics

    SciTech Connect (OSTI)

    Tare, Jeffrey D. Esguerra, Jose Perico H.

    2014-01-15

    Using the momentum-space approach, we obtain bound states for multiple Dirac-? wells in the framework of space-fractional quantum mechanics. Introducing first an attractive Dirac-comb potential, i.e., Dirac comb with strength ?g (g > 0), in the space-fractional Schrdinger equation we show that the problem of obtaining eigenenergies of a system with N Dirac-? wells can be reduced to a problem of obtaining the eigenvalues of an N N matrix. As an illustration we use the present matrix formulation to derive expressions satisfied by the bound-state energies of N = 1, 2, 3 delta wells. We also obtain the corresponding wave functions and express them in terms of Fox's H-function.

  17. Coordination of Copper to the Membrane-Bound Form of α-Synuclein

    SciTech Connect (OSTI)

    Dudzik, Christopher G.; Walter, Eric D.; Abrams, Benjamin S.; Jurica, Melissa S.; Millhauser, Glenn L.

    2013-01-01

    Aggregation of the 140 amino acid protein α-synuclein (α-syn) is linked to the development of Parkinson's disease (PD). α-Syn is a copper binding protein with potential function as a regulator of metal dependent redox activity. Epidemiological studies suggest that human exposure to excess copper increases the incidence of PD. α-Syn exists in both solution and membrane bound forms. Previous work evaluated the Cu2+ uptake for α-syn in solution and identified Met1-Asp2 and His50 as primary contributors to the coordination shell, with a dissociation constant of approximately 0.1 nM. When bound to the membrane bilayer, α-syn takes on a predominantly helical conformation, which spatially separates His50 from the protein N-terminus and is therefore incompatible with the copper coordination geometry of the solution state. Here we use circular dichroism and electron paramagnetic resonance (continuous wave and pulsed) to evaluate copper coordination to the membrane bound form of α-syn. In this molecular environment, Cu2+ binds exclusively to the protein N-terminus (Met1-Asp2) with no participation from His50. Copper does not alter the membrane bound α-syn conformation, or enhance the protein's release from the bilayer. The Cu2+ affinity is similar to that identified for solution α-syn suggesting that copper coordination is retained in the membrane. Consideration of these results suggests that copper exerts its greatest conformational affect on the solution form of α-syn and this species may therefore be precursor to PD arising from environmental copper exposure.

  18. Summary of Bounding Requirements for the NGNP Demonstration Plant F&ORs

    SciTech Connect (OSTI)

    Not Listed

    2008-06-01

    This report documents bounding functional and operating requirements (F&ORs)for the Next Generation Nuclear Plant (NGNP) Project to support selection of the nuclear system design and specification of the operating conditions and configuration of NGNP once the nuclear system design is selected. These requirements supplement the detailed F&ORs for NGNP developed in the FY07 NGNP Pre-conceptual design work.

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

    SciTech Connect (OSTI)

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

    2009-01-01

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

  20. A Branch and Bound Approach for Truss Topology Design Problems with Valid Inequalities

    SciTech Connect (OSTI)

    Cerveira, Adelaide; Agra, Agostinho; Bastos, Fernando; Varum, Humberto

    2010-09-30

    One of the classical problems in the structural optimization field is the Truss Topology Design Problem (TTDP) which deals with the selection of optimal configuration for structural systems for applications in mechanical, civil, aerospace engineering, among others. In this paper we consider a TTDP where the goal is to find the stiffest truss, under a given load and with a bound on the total volume. The design variables are the cross-section areas of the truss bars that must be chosen from a given finite set. This results in a large-scale non-convex problem with discrete variables. This problem can be formulated as a Semidefinite Programming Problem (SDP problem) with binary variables. We propose a branch and bound algorithm to solve this problem. In this paper it is considered a binary formulation of the problem, to take advantage of its structure, which admits a Knapsack problem as subproblem. Thus, trying to improve the performance of the Branch and Bound, at each step, some valid inequalities for the Knapsack problem are included.

  1. Two nucleon systems at <math display='inline'>mπ~450MeVmath> from lattice QCD

    SciTech Connect (OSTI)

    Orginos, Kostas; Parreño, Assumpta; Savage, Martin J.; Beane, Silas R.; Chang, Emmanuel; Detmold, William

    2015-12-23

    Nucleon-nucleon systems are studied with lattice quantum chromodynamics at a pion mass of $m_\\pi\\sim 450~{\\rm MeV}$ in three spatial volumes using $n_f=2+1$ flavors of light quarks. At the quark masses employed in this work, the deuteron binding energy is calculated to be $B_d = 14.4^{+3.2}_{-2.6} ~{\\rm MeV}$, while the dineutron is bound by $B_{nn} = 12.5^{+3.0}_{-5.0}~{\\rm MeV}$. Over the range of energies that are studied, the S-wave scattering phase shifts calculated in the 1S0 and 3S1-3D1 channels are found to be similar to those in nature, and indicate repulsive short-range components of the interactions, consistent with phenomenological nucleon-nucleon interactions. In both channels, the phase shifts are determined at three energies that lie within the radius of convergence of the effective range expansion, allowing for constraints to be placed on the inverse scattering lengths and effective ranges. Thus, the extracted phase shifts allow for matching to nuclear effective field theories, from which low energy counterterms are extracted and issues of convergence are investigated. As part of the analysis, a detailed investigation of the single hadron sector is performed, enabling a precise determination of the violation of the Gell-Mann–Okubo mass relation.

  2. Application of the bounds-analysis approach to arsenic and gallium antisite defects in gallium arsenide

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

    Wright, A. F.; Modine, N. A.

    2015-01-23

    The As antisite in GaAs (AsGa) has been the subject of numerous experimental and theoretical studies. Recent density-functional-theory (DFT) studies report results in good agreement with experimental data for the +2, +1, and 0 charge states of the stable EL2 structure, the 0 charge state of the metastable EL2* structure, and the activation energy to transform from EL2* to EL2 in the 0 charge state. However, these studies did not report results for EL2* in the -1 charge state. In this paper, we report new DFT results for the +2, +1, 0, and -1 charge states of AsGa, obtained usingmore » a semilocal exchange-correlation functional and interpreted using a bounds-analysis approach. In good agreement with experimental data, we find a -1/0 EL2* level 0.06 eV below the conduction-band edge and an activation energy of 0.05 eV to transform from EL2* to EL2 in the -1 charge state. While the Ga antisite in GaAs (GaAs) has not been studied as extensively as AsGa, experimental studies report three charge states (-2, -1, 0) and two levels (-2/-1, -1/0) close to the valence-band edge. Recent DFT studies report the same charge states, but the levels are found to be well-separated from the valence-band edge. To resolve this disagreement, we performed new DFT calculations for GaAs and interpreted them using a bounds analysis. The analysis identified the -1 and 0 charge states as hole states weakly bound to a highly-localized -2 charge state. Moreover, the -2/-1, -1/0 levels were found to be near the valence-band edge, in good agreement with the experimental data.« less

  3. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print DNA replication is a critical step in the life of all organisms, insuring that each new cell gets an accurate copy of the genome. Among the legions of proteins required to do this work, the DNA-slicing "flap endonuclease" FEN1 plays a key role. Much of FEN1's structure was solved previously, but the DNA-free structure failed to expose information about the mechanics of how it works. An international team of scientists led by

  4. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print DNA replication is a critical step in the life of all organisms, insuring that each new cell gets an accurate copy of the genome. Among the legions of proteins required to do this work, the DNA-slicing "flap endonuclease" FEN1 plays a key role. Much of FEN1's structure was solved previously, but the DNA-free structure failed to expose information about the mechanics of how it works. An international team of scientists led by

  5. Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human

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

    Survivor Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human Survivor Print Ebolavirus, one of two members of the family of filoviruses, causes a severe hemorrhagic fever with 50-90% human mortality. That no vaccines or treatments are yet available combined with the frequent re-emergence of the virus, its high prevalence among wildlife, and ease of importation of the virus make it a significant public health concern. A team of researchers from the Scripps Research

  6. Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human

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

    Survivor Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human Survivor Print Ebolavirus, one of two members of the family of filoviruses, causes a severe hemorrhagic fever with 50-90% human mortality. That no vaccines or treatments are yet available combined with the frequent re-emergence of the virus, its high prevalence among wildlife, and ease of importation of the virus make it a significant public health concern. A team of researchers from the Scripps Research

  7. Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human

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

    Survivor Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human Survivor Print Ebolavirus, one of two members of the family of filoviruses, causes a severe hemorrhagic fever with 50-90% human mortality. That no vaccines or treatments are yet available combined with the frequent re-emergence of the virus, its high prevalence among wildlife, and ease of importation of the virus make it a significant public health concern. A team of researchers from the Scripps Research

  8. Quantum localization and bound-state formation in Bose-Einstein condensates

    SciTech Connect (OSTI)

    Franzosi, Roberto; Giampaolo, Salvatore M.; Illuminati, Fabrizio

    2010-12-15

    We discuss the possibility of exponential quantum localization in systems of ultracold bosonic atoms with repulsive interactions in open optical lattices without disorder. We show that exponential localization occurs in the maximally excited state of the lowest energy band. We establish the conditions under which the presence of the upper energy bands can be neglected, determine the successive stages and the quantum phase boundaries at which localization occurs, and discuss schemes to detect it experimentally by visibility measurements. The discussed mechanism is a particular type of quantum localization that is intuitively understood in terms of the interplay between nonlinearity and a bounded energy spectrum.

  9. Industrial cogeneration case study No. 2: American Cyanamid Chemical Company, Bound Brook, New Jersey

    SciTech Connect (OSTI)

    Not Available

    1980-01-01

    Within a project for evaluating the economics of cogeneration for industrial plants with an electrical capacity of 10,000 to 30,000 kW, the American Cyanamid plant at Bound Brook, NJ was selected for study. Built between 1915 and 1920 this power plant was converted in the 1960's from coal-fueling to oil and natural gas. Information is presented on the plant site, fuel usage, generation costs, comparative cost of purchasable electric power, equipment used, performance, and reliability and capital and maintenance costs. (LCL)

  10. Three-Body Recombination into Deep Bound States in a Bose Gas with Large Scattering Length

    SciTech Connect (OSTI)

    Braaten, Eric; Hammer, H.-W.

    2001-10-15

    An effective field theory for the three-body system with large two-body scattering length a is applied to three-body recombination into deep bound states in a Bose gas. The recombination constant {alpha} is calculated to first order in the short-distance interactions that allow the recombination. For a<0 , the dimensionless combination m{alpha}/({Dirac_h}a{sup 4}) is a periodic function of ln|a| that exhibits resonances at values of a that differ by multiplicative factors of 22.7. This dramatic behavior should be observable near a Feshbach resonance when a becomes large and negative.

  11. Preparatory steps for a robust dynamic model for organically bound tritium dynamics in agricultural crops

    SciTech Connect (OSTI)

    Melintescu, A.; Galeriu, D.; Diabate, S.; Strack, S.

    2015-03-15

    The processes involved in tritium transfer in crops are complex and regulated by many feedback mechanisms. A full mechanistic model is difficult to develop due to the complexity of the processes involved in tritium transfer and environmental conditions. First, a review of existing models (ORYZA2000, CROPTRIT and WOFOST) presenting their features and limits, is made. Secondly, the preparatory steps for a robust model are discussed, considering the role of dry matter and photosynthesis contribution to the OBT (Organically Bound Tritium) dynamics in crops.

  12. Lower-bound estimates of energy efficiency in the federal sector

    SciTech Connect (OSTI)

    Dirks, J.A.; Shankle, S.A.; Stucky, D.J.; Elliott, D.B.

    1994-08-01

    The Energy Programs Directorate (EPD) at the Pacific Northwest Laboratory (PNL) was tasked by the DOE Federal Energy Management Program (FEMP) to provide lower-bound estimates of the energy and dollar savings that could be realized by implementing all life-cycle cost-effective retrofits within the federal sector. FEMP has a responsibility to recommend a course of action to DOE regarding the design, implementation, and management of a federal energy efficiency fund. The information in this report is provided to assist FEMP in developing its position.

  13. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print DNA replication is a critical step in the life of all organisms, insuring that each new cell gets an accurate copy of the genome. Among the legions of proteins required to do this work, the DNA-slicing "flap endonuclease" FEN1 plays a key role. Much of FEN1's structure was solved previously, but the DNA-free structure failed to expose information about the mechanics of how it works. An international team of scientists led by

  14. Structure of DNA-Bound FEN1 Reveals Mechanism of Action

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

    Structure of DNA-Bound FEN1 Reveals Mechanism of Action Print DNA replication is a critical step in the life of all organisms, insuring that each new cell gets an accurate copy of the genome. Among the legions of proteins required to do this work, the DNA-slicing "flap endonuclease" FEN1 plays a key role. Much of FEN1's structure was solved previously, but the DNA-free structure failed to expose information about the mechanics of how it works. An international team of scientists led by

  15. Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human

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

    Survivor Structure of the Ebola Virus Glycoprotein Bound to an Antibody from a Human Survivor Print Ebolavirus, one of two members of the family of filoviruses, causes a severe hemorrhagic fever with 50-90% human mortality. That no vaccines or treatments are yet available combined with the frequent re-emergence of the virus, its high prevalence among wildlife, and ease of importation of the virus make it a significant public health concern. A team of researchers from the Scripps Research

  16. The viscosity to entropy ratio: From string theory motivated bounds to warm dense matter

    SciTech Connect (OSTI)

    Faussurier, G.; Libby, S. B.; Silvestrelli, P. L.

    2014-07-04

    Here, we study the ratio of viscosity to entropy density in Yukawa one-component plasmas as a function of coupling parameter at fixed screening, and in realistic warm dense matter models as a function of temperature at fixed density. In these two situations, the ratio is minimized for values of the coupling parameters that depend on screening, and for temperatures that in turn depend on density and material. In this context, we also examine Rosenfeld arguments relating transport coefficients to excess reduced entropy for Yukawa one-component plasmas. For these cases we show that this ratio is always above the lower-bound conjecture derived from string theory ideas.

  17. Precise determination of the deuteron spin structure at low to moderate <math>Q2math> with CLAS and extraction of the neutron contribution

    SciTech Connect (OSTI)

    Guler, N.; Fersch, R. G.; Kuhn, S. E.; Bosted, P.; Griffioen, K. A.; Keith, C.; Minehart, R.; Prok, Y.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A.; Briscoe, W. J.; Brooks, W. K.; Bltmann, S.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crabb, D.; Crede, V.; D'Angelo, A.; Dashyan, N.; Deur, A.; Djalali, C.; Dodge, G. E.; Dupre, R.; Alaoui, A. El; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Garon, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Livingston, K.; Lu, H. Y.; Mayer, M.; MacGregor, I. J. D.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabati, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Simonyan, A.; Skorodumina, Iu.; Sokhan, D.; Sparveris, N.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tian, Ye; Tkachenko, S.; Ungaro, M.; Voutier, E.; Walford, N. K.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2015-11-02

    In this study, we present the final results for the deuteron spin structure functions obtained from the full data set collected with Jefferson Lab's CLAS in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2 and 5.8 GeV were scattered from deuteron (15ND3) targets, dynamically polarized along the beam direction, and detected with CLAS. From the measured double spin asymmetry, the virtual photon absorption asymmetry Ad1 and the polarized structure function gd1 were extracted over a wide kinematic range (0.05 GeV2 < Q2 < 5 GeV2 and 0.9 GeV < W < 3 GeV). We use an unfolding procedure and a parametrization of the corresponding proton results to extract from these data the polarized structure functions An1 and g1n of the (bound) neutron, which are so far unknown in the resonance region, W < 2 GeV. We compare our final results, including several moments of the deuteron and neutron spin structure functions, with various theoretical models and expectations as well as parametrizations of the world data. The unprecedented precision and dense kinematic coverage of these data can aid in future extractions of polarized parton distributions, tests of perturbative QCD predictions for the quark polarization at large x, a better understanding of quark-hadron duality, and more precise values for higher-twist matrix elements in the framework of the Operator Product Expansion.

  18. Comment on “Effects of damping solitary wave in a viscosity bounded plasma” [Phys. Plasmas 21, 022118 (2014)

    SciTech Connect (OSTI)

    Ghosh, Uday Narayan Chatterjee, Prasanta; Roychoudhury, Rajkumar

    2015-07-15

    Recently Gun Li et al. discussed “Effects of damping solitary wave in a viscosity bounded plasma” [Phys. Plasmas 21, 022118 (2014)]. The paper contains some serious errors which have been pointed out in this Comment.

  19. Encapsulation and Characterization of Proton-Bound Amine Homodimers in a Water Soluble, Self-Assembled Supramolecular Host

    SciTech Connect (OSTI)

    Pluth, Michael; Fiedler, Dorothea; Mugridge, Jeffrey; Bergman, Robert; Raymond, Kenneth

    2008-10-01

    Cyclic amines can be encapsulated in a water-soluble self-assembled supramolecular host upon protonation. The hydrogen bonding ability of the cyclic amines, as well as the reduced degrees of rotational freedom, allows for the formation of proton-bound homodimers inside of the assembly which are otherwise not observable in aqueous solution. The generality of homodimer formation was explored with small N-alkyl aziridines, azetidines, pyrrolidines and piperidines. Proton-bound homodimer formation is observed for N-alkylaziridines (R = methyl, isopropyl, tert-butyl), N-alkylazetidines (R = isopropyl, tertbutyl), and N-methylpyrrolidine. At high concentration, formation of a proton-bound homotrimer is observed in the case of N-methylaziridine. The homodimers stay intact inside the assembly over a large concentration range, thereby suggesting cooperative encapsulation. Both G3(MP2)B3 and G3B3 calculations of the proton-bound homodimers were used to investigate the enthalpy of the hydrogen bond in the proton-bound homodimers and suggest that the enthalpic gain upon formation of the proton-bound homodimers may drive guest encapsulation.

  20. BPS-like bound and thermodynamics of the charged BTZ black hole

    SciTech Connect (OSTI)

    Cadoni, Mariano; Monni, Cristina

    2009-07-15

    The charged Banados-Teitelboim-Zanelli (BTZ) black hole is plagued by several pathologies: (a) Divergent boundary terms are present in the action; hence, we have a divergent black-hole mass. (b) Once a finite, renormalized, mass M is defined, black-hole states exist for arbitrarily negative values of M. (c) There is no upper bound on the charge Q. We show that these pathological features are an artifact of the renormalization procedure. They can be completely removed by using an alternative renormalization scheme leading to a different definition M{sub 0} of the black-hole mass, which is the total energy inside the horizon. The new mass satisfies a BPS-like bound M{sub 0}{>=}({pi}/2)Q{sup 2}, and the heat capacity of the hole is positive. We also discuss the black-hole thermodynamics that arises when M{sub 0} is interpreted as the internal energy of the system. We show, using three independent approaches (black-hole thermodynamics, Einstein equations, and Euclidean action formulation), that M{sub 0} satisfies the first law if a term describing the mechanical work done by the electrostatic pressure is introduced.

  1. Consideration of critically when directly disposing highly enriched spent nuclear fuel in unsaturated tuff: Bounding estimates

    SciTech Connect (OSTI)

    Rechard, R.P.; Tierney, M.S.; Sanchez, L.C.; Martell, M.-A.

    1996-05-01

    This report presents one of 2 approaches (bounding calculations) which were used in a 1994 study to examine the possibility of a criticality in a repository. Bounding probabilities, although rough, point to the difficulty of creating conditions under which a critical mass could be assembled (container corrosion, separation of neutron absorbers from fissile material, collapse or precipitation of fissile material) and how significant the geochemical and hydrologic phenomena are. The study could not conceive of a mechanism consistent with conditions under which an atomic explosion could occur. Should a criticality occur in or near a container in the future, boundary consequence calculations showed that fissions from one critical event (<10{sup 20} fissions, if similar to aqueous and metal accidents and experiments) are quite small compared to the amount of fissions represented by the spent fuel itself. If it is assumed that the containers necessary to hold the highly enriched spent fuel went critical once per day for 1 million years, creating an energy release of about 10{sup 20} fissions, the number of fissions equals about 10{sup 28}, which corresponds to only 1% of the fission inventory in a repository containing 70,000 metric tons of heavy metal, the expected size for the proposed repository at Yucca Mountain, Nevada.

  2. Finite Energy and Bounded Actuator Attacks on Cyber-Physical Systems

    SciTech Connect (OSTI)

    Djouadi, Seddik M; Melin, Alexander M; Ferragut, Erik M; Laska, Jason A; Dong, Jin; Drira, Anis

    2015-01-01

    As control system networks are being connected to enterprise level networks for remote monitoring, operation, and system-wide performance optimization, these same connections are providing vulnerabilities that can be exploited by malicious actors for attack, financial gain, and theft of intellectual property. Much effort in cyber-physical system (CPS) protection has focused on protecting the borders of the system through traditional information security techniques. Less effort has been applied to the protection of cyber-physical systems from intelligent attacks launched after an attacker has defeated the information security protections to gain access to the control system. In this paper, attacks on actuator signals are analyzed from a system theoretic context. The threat surface is classified into finite energy and bounded attacks. These two broad classes encompass a large range of potential attacks. The effect of theses attacks on a linear quadratic (LQ) control are analyzed, and the optimal actuator attacks for both finite and infinite horizon LQ control are derived, therefore the worst case attack signals are obtained. The closed-loop system under the optimal attack signals is given and a numerical example illustrating the effect of an optimal bounded attack is provided.

  3. Effective-range expansion for two coupled channels and properties of bound states

    SciTech Connect (OSTI)

    Blokhintsev, L. D.

    2011-07-15

    The S matrix and the scattering-amplitude matrix (F matrix) are considered for the case of two coupled elastic-scattering channels differing by the values of the orbital angular momentum (l{sub 1} and l{sub 2} = l{sub 1} + 2). The matrix elements of the S and F matrices in the absence of Coulomb interaction are expressed in terms of the matrix elements of the matrix K{sup -1} inverse to the reaction K matrix. The elements of the K{sup -1} matrix are written in the form of expansions that are generalizations of the single-channel effective-range expansion. If there is a bound state in the system of colliding particles, then an analytic continuation of these expansions to the region of negative energies makes it possible to obtain both the position of the pole corresponding to this bound state and the residues of scattering amplitudes at this pole, the respective vertex constants and asymptotic normalization coefficients being expressed in terms of these residues. By way of example, the developed formalism is applied to describing triplet neutron-proton scattering.

  4. Importance of Lorentz structure in the parton model: Target mass corrections, transverse momentum dependence, positivity bounds

    SciTech Connect (OSTI)

    D'Alesio, U.; Leader, E.; Murgia, F.

    2010-02-01

    We show that respecting the underlying Lorentz structure in the parton model has very strong consequences. Failure to insist on the correct Lorentz covariance is responsible for the existence of contradictory results in the literature for the polarized structure function g{sub 2}(x), whereas with the correct imposition we are able to derive the Wandzura-Wilczek relation for g{sub 2}(x) and the target-mass corrections for polarized deep inelastic scattering without recourse to the operator product expansion. We comment briefly on the problem of threshold behavior in the presence of target-mass corrections. Careful attention to the Lorentz structure has also profound implications for the structure of the transverse momentum dependent parton densities often used in parton model treatments of hadron production, allowing the k{sub T} dependence to be derived explicitly. It also leads to stronger positivity and Soffer-type bounds than usually utilized for the collinear densities.

  5. Bound on quantum computation time: Quantum error correction in a critical environment

    SciTech Connect (OSTI)

    Novais, E.; Mucciolo, Eduardo R.; Baranger, Harold U.

    2010-08-15

    We obtain an upper bound on the time available for quantum computation for a given quantum computer and decohering environment with quantum error correction implemented. First, we derive an explicit quantum evolution operator for the logical qubits and show that it has the same form as that for the physical qubits but with a reduced coupling strength to the environment. Using this evolution operator, we find the trace distance between the real and ideal states of the logical qubits in two cases. For a super-Ohmic bath, the trace distance saturates, while for Ohmic or sub-Ohmic baths, there is a finite time before the trace distance exceeds a value set by the user.

  6. Excitation of surface modes by electron beam in semi-bounded quantum plasma

    SciTech Connect (OSTI)

    Mohamed, B. F.; Elbasha, N. M.

    2015-10-15

    The excitation of the TM surface modes due to the interaction of electron beam with a semi-bounded quantum magnetized plasma is investigated. The generated current and the perturbed densities of the electron beam and plasma are obtained. The wave equation that describes the excited fields has been solved to obtain the dispersion relation for these modes. It is found that the quantum effects play important role for frequencies less and bigger than plasma frequency such that the phase velocity of modes increases with increasing the quantum effects compared to the classical case. It has also been displayed that in the absence of external magnetic field, the surface modes appear in the all regions of the wavelength while they have been only excited for high wavenumber in the presence of the magnetic field. Besides, it has been shown that the dispersion curves of the modes depend essentially on the density ratio of beam and plasma.

  7. Upper bound on parity-violating neutron spin rotation in {sup 4}He

    SciTech Connect (OSTI)

    Snow, W. M.; Luo, D.; Walbridge, S. B.; Crawford, B. E.; Gan, K.; Micherdzinska, A. M.; Opper, A. K.; Heckel, B. R.; Swanson, H. E.; Sharapov, E. I.; Zhumabekova, V.

    2011-02-15

    We report an upper bound on parity-violating neutron spin rotation in {sup 4}He. This experiment is the most sensitive search for neutron-weak optical activity yet performed and represents a significant advance in precision in comparison to past measurements in heavy nuclei. The experiment was performed at the NG-6 slow-neutron beamline at the National Institute of Standards and Technology (NIST) Center for Neutron Research. Our result for the neutron spin rotation angle per unit length in {sup 4}He is d{phi}/dz=[+1.7{+-}9.1(stat.){+-}1.4(sys.)]x10{sup -7} rad/m. The statistical uncertainty is smaller than current estimates of the range of possible values of d{phi}/dz in n+{sup 4}He.

  8. Nonlinear interaction between surface plasmons and ion oscillations in a semi-bounded collisional quantum plasma

    SciTech Connect (OSTI)

    Khorashadizadeh, S. M. Taheri Boroujeni, S.; Niknam, A. R.

    2015-11-15

    In this paper, we have investigated the nonlinear interaction between high-frequency surface plasmons and low-frequency ion oscillations in a semi-bounded collisional quantum plasma. By coupling the nonlinear Schrodinger equation and quantum hydrodynamic model, and taking into account the ponderomotive force, the dispersion equation is obtained. By solving this equation, it is shown that there is a modulational instability in the system, and collisions and quantum forces play significant roles on this instability. The quantum tunneling increases the phase and group velocities of the modulated waves and collisions increase the growth rate of the modulational instability. It is also shown that the effect of quantum forces and collisions is more significant in high modulated wavenumber regions.

  9. Appearance of bound states in random potentials with applications to soliton theory

    SciTech Connect (OSTI)

    Derevyanko, S. A.

    2011-07-15

    We analyze the stochastic creation of a single bound state (BS) in a random potential with a compact support. We study both the Hermitian Schroedinger equation and non-Hermitian Zakharov-Shabat systems. These problems are of special interest in the inverse scattering method for Korteveg-de-Vries and the nonlinear Schroedinger equations since soliton solutions of these two equations correspond to the BSs of the two aforementioned linear eigenvalue problems. Analytical expressions for the average width of the potential required for the creation of the first BS are given in the approximation of delta-correlated Gaussian potential and additionally different scenarios of eigenvalue creation are discussed for the non-Hermitian case.

  10. Sandia National Laboratories/New Mexico existing environmental analyses bounding environmental test facilities.

    SciTech Connect (OSTI)

    May, Rodney A.; Bailey-White, Brenda E.; Cantwell, Amber

    2009-06-01

    This report identifies current environmental operating parameters for the various test and support facilities at SNL/NM. The intent of this report is solely to provide the limits which bound the facilities' operations. Understanding environmental limits is important to maximizing the capabilities and working within the existing constraints of each facility, and supports the decision-making process in meeting customer requests, cost and schedule planning, modifications to processes, future commitments, and use of resources. Working within environmental limits ensures that mission objectives will be met in a manner that protects human health and the environment. It should be noted that, in addition to adhering to the established limits, other approvals and permits may be required for specific projects.

  11. Most sub-arcsecond companions of Kepler exoplanet candidate host stars are gravitationally bound

    SciTech Connect (OSTI)

    Horch, Elliott P.; Howell, Steve B.; Everett, Mark E.; Ciardi, David R. E-mail: steve.b.howell@nasa.gov E-mail: ciardi@ipac.caltech.edu

    2014-11-01

    Using the known detection limits for high-resolution imaging observations and the statistical properties of true binary and line-of-sight companions, we estimate the binary fraction of Kepler exoplanet host stars. Our speckle imaging programs at the WIYN 3.5 m and Gemini North 8.1 m telescopes have observed over 600 Kepler objects of interest and detected 49 stellar companions within ?1 arcsec. Assuming binary stars follow a log-normal period distribution for an effective temperature range of 3000-10,000 K, then the model predicts that the vast majority of detected sub-arcsecond companions are long period (P > 50 yr), gravitationally bound companions. In comparing the model predictions to the number of real detections in both observational programs, we conclude that the overall binary fraction of host stars is similar to the 40%-50% rate observed for field stars.

  12. The viscosity to entropy ratio: From string theory motivated bounds to warm dense matter

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

    Faussurier, G.; Libby, S. B.; Silvestrelli, P. L.

    2014-07-04

    Here, we study the ratio of viscosity to entropy density in Yukawa one-component plasmas as a function of coupling parameter at fixed screening, and in realistic warm dense matter models as a function of temperature at fixed density. In these two situations, the ratio is minimized for values of the coupling parameters that depend on screening, and for temperatures that in turn depend on density and material. In this context, we also examine Rosenfeld arguments relating transport coefficients to excess reduced entropy for Yukawa one-component plasmas. For these cases we show that this ratio is always above the lower-bound conjecturemore » derived from string theory ideas.« less

  13. Switching of bound vector solitons for the coupled nonlinear Schroedinger equations with nonhomogenously stochastic perturbations

    SciTech Connect (OSTI)

    Sun Zhiyuan; Yu Xin; Liu Ying; Gao Yitian

    2012-12-15

    We investigate the dynamics of the bound vector solitons (BVSs) for the coupled nonlinear Schroedinger equations with the nonhomogenously stochastic perturbations added on their dispersion terms. Soliton switching (besides soliton breakup) can be observed between the two components of the BVSs. Rate of the maximum switched energy (absolute values) within the fixed propagation distance (about 10 periods of the BVSs) enhances in the sense of statistics when the amplitudes of stochastic perturbations increase. Additionally, it is revealed that the BVSs with enhanced coherence are more robust against the perturbations with nonhomogenous stochasticity. Diagram describing the approximate borders of the splitting and non-splitting areas is also given. Our results might be helpful in dynamics of the BVSs with stochastic noises in nonlinear optical fibers or with stochastic quantum fluctuations in Bose-Einstein condensates.

  14. Structural Diversity in Free and Bound States of Intrinsically Disordered Protein Phosphatase 1 Regulators

    SciTech Connect (OSTI)

    Marsh, J.A.; Allaire, M.; Dancheck, B.; Ragusa, M.J.; Forman-Kay, J.D.; Peti, Wolfgang

    2010-09-08

    Complete folding is not a prerequisite for protein function, as disordered and partially folded states of proteins frequently perform essential biological functions. In order to understand their functions at the molecular level, we utilized diverse experimental measurements to calculate ensemble models of three nonhomologous, intrinsically disordered proteins: I-2, spinophilin, and DARPP-32, which bind to and regulate protein phosphatase 1 (PP1). The models demonstrate that these proteins have dissimilar propensities for secondary and tertiary structure in their unbound forms. Direct comparison of these ensemble models with recently determined PP1 complex structures suggests a significant role for transient, preformed structure in the interactions of these proteins with PP1. Finally, we generated an ensemble model of partially disordered I-2 bound to PP1 that provides insight into the relationship between flexibility and biological function in this dynamic complex.

  15. Bounds on the sample complexity for private learning and private data release

    SciTech Connect (OSTI)

    Kasiviswanathan, Shiva; Beime, Amos; Nissim, Kobbi

    2009-01-01

    Learning is a task that generalizes many of the analyses that are applied to collections of data, and in particular, collections of sensitive individual information. Hence, it is natural to ask what can be learned while preserving individual privacy. [Kasiviswanathan, Lee, Nissim, Raskhodnikova, and Smith; FOCS 2008] initiated such a discussion. They formalized the notion of private learning, as a combination of PAC learning and differential privacy, and investigated what concept classes can be learned privately. Somewhat surprisingly, they showed that, ignoring time complexity, every PAC learning task could be performed privately with polynomially many samples, and in many natural cases this could even be done in polynomial time. While these results seem to equate non-private and private learning, there is still a significant gap: the sample complexity of (non-private) PAC learning is crisply characterized in terms of the VC-dimension of the concept class, whereas this relationship is lost in the constructions of private learners, which exhibit, generally, a higher sample complexity. Looking into this gap, we examine several private learning tasks and give tight bounds on their sample complexity. In particular, we show strong separations between sample complexities of proper and improper private learners (such separation does not exist for non-private learners), and between sample complexities of efficient and inefficient proper private learners. Our results show that VC-dimension is not the right measure for characterizing the sample complexity of proper private learning. We also examine the task of private data release (as initiated by [Blum, Ligett, and Roth; STOC 2008]), and give new lower bounds on the sample complexity. Our results show that the logarithmic dependence on size of the instance space is essential for private data release.

  16. Feasibility exploration of throughfold as a predictor for target loading and associated error bounds. Master`s thesis

    SciTech Connect (OSTI)

    Rongone, K.G.

    1994-12-01

    Various applications of the Fredholm integral equation appear in different fields of study. An application of particular interest to the Air Force arises in determination of target loading from nuclear effects simulations. Current techniques first unfold the incident spectrum then determine target loading; resulting spectrum and loading are assumed exact. This study investigates the feasibility of a new method, through-fold, for directly determining defensible error bounds on target loading. Through-fold uses a priori information to define input data and represents target response with a linear combination of instrument responses plus a remainder to derive a quadratic expression for exact target loading. This study uses a simplified, linear version of the quadratic expression. Through-fold feasibility is tested by comparing error bounds based on three target loading functions. The three test cases include an exact linear combination of instrument responses, the same combination plus a positive remainder, and the same combination plus a negative remainder. Total error bounds reduced from 100% to 35% in cases number l and number 2. In case number 3 error bound was reduced to 48%. These results indicate that through-fold has promise as a predictor of error bounds on target loading.

  17. Neutron scattering study of spin ordering and stripe pinning in superconducting <math>La1.93Sr0.07CuO4math>

    SciTech Connect (OSTI)

    Jacobsen, H.; Zaliznyak, I. A.; Savici, A. T.; Winn, B. L.; Chang, S.; Hücker, M.; Gu, G. D.; Tranquada, J. M.

    2015-11-20

    The relationships among charge order, spin fluctuations, and superconductivity in underdoped cuprates remain controversial. We use neutron scattering techniques to study these phenomena in <math>La1.93Sr0.07CuO4math> a superconductor with a transition temperature of Tc = 20 K. At T<< Tc, we find incommensurate spin fluctuations with a quasielastic energy spectrum and no sign of a gap within the energy range from 0.2 to 15 meV. A weak elastic magnetic component grows below ~ 10 K, consistent with results from local probes. Regarding the atomic lattice, we have discovered unexpectedly strong fluctuations of the CuO6 octahedra about Cu-O bonds, which are associated with inequivalent O sites within the CuO2 planes. Moreover, we observed a weak elastic (3 30) superlattice peak that implies a reduced lattice symmetry. The presence of inequivalent O sites rationalizes various pieces of evidence for charge stripe order in underdoped La2-xSrxCuO4. The coexistence of superconductivity with quasi-static spin-stripe order suggests the presence of intertwined orders; however, the rotation of the stripe orientation away from the Cu-O bonds might be connected with evidence for a finite gap at the nodal points of the superconducting gap function.

  18. Generation of bound states of pulses in a soliton laser with complex relaxation of a saturable absorber

    SciTech Connect (OSTI)

    Zolotovskii, I O; Korobko, D A; Okhotnikov, O G; Gumenyuk, R V

    2015-01-31

    A numerical model of a soliton fibre laser with a semiconductor saturable absorber mirror (SESAM), characterised by the complex dynamics of absorption relaxation, is considered. It is shown that stationary bound states of pulses can be formed in this laser as a result of their interaction via the dispersion-wave field. The stability of stationary bound states of several pulses is analysed. It is shown that an increase in the number of pulses in a stationary bound state leads eventually to its decay and formation of a random bunch. It is found that the bunch stability is caused by the manifestation of nonlinear self-phase modulation, which attracts pulses to the bunch centre. The simulation results are in qualitative agreement with experimental data. (nonlinear optical phenomena)

  19. Analytic solution for thermal resistance of regions bounded by concentric N-gons (N = 3,4,. )

    SciTech Connect (OSTI)

    Naterer, G.F. )

    1993-01-01

    The thermal resistance for steady-state, two-dimensional heat flow in internal regions bounded by concentric polygons with isothermal boundary conditions is computed by a conformal mapping procedure. The coordinate transformation functions in the complex plane and the heat conduction shape factors may be expressed in a closed form but they require numerical integration. The analytic approach generalizes solutions given for specific geometries such as the domain bounded by concentric squares and it may be extended to the limiting case of concentric cylinders. 9 refs.

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

    SciTech Connect (OSTI)

    Collaboration: Pierre Auger Collaboration

    2013-05-01

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

  1. Three region analysis of a bounded plasma using particle in cell and fluid techniques. Doctoral thesis

    SciTech Connect (OSTI)

    Nichols, D.F.

    1994-09-01

    A detailed collisionless sheath theory and a three-region collisional model of a bounded plasma are presented, and the suitability of the collisional model for analysis of ignited mode thermionic converters is investigated. The sheath theory extends previous analyses to regimes in which the sheath potential and electron temperatures are comparable in magnitude. In all operating regimes typical of a ignited mode thermionic converter, the predicted sheaths extend several mean-free paths. The apparent collisionality of the sheaths prompted development of a collisional, three-region model of the converter plasma. By interfacing Particle-in-Cell regions (for the sheaths) and fluid regions (for the bulk of the plasma), a time-dependent, wall-to-wall model of the plasma in the inter-electrode space is created. The components of the model are tested and validated against analytic solutions and against one another, then applied to the analysis of an ignited mode thermionic converter. Under ignited mode operating conditions, the electron velocity distribution at the plasma/sheath boundary is found to be inconsistent with that assumed in the model development, and the calculation diverges. The observed distribution is analyzed and a new basis set of distribution functions is suggested that should permit application of the hybrid model to ignited mode thermionic converters.

  2. The use of artificially intelligent agents with bounded rationality in the study of economic markets

    SciTech Connect (OSTI)

    Rajan, V.; Slagle, J.R.

    1996-12-31

    The concepts of {open_quote}knowledge{close_quote} and {open_quote}rationality{close_quote} are of central importance to fields of science that are interested in human behavior and learning, such as artificial intelligence, economics, and psychology. The similarity between artificial intelligence and economics - both are concerned with intelligent thought, rational behavior, and the use and acquisition of knowledge - has led to the use of economic models as a paradigm for solving problems in distributed artificial intelligence (DAI) and multi agent systems (MAS). What we propose is the opposite; the use of artificial intelligence in the study of economic markets. Over the centuries various theories of market behavior have been advanced. The prevailing theory holds that an asset`s current price converges to the risk adjusted value of the rationally expected dividend stream. While this rational expectations model holds in equilibrium or near-equilibrium conditions, it does not sufficiently explain conditions of market disequilibrium. An example of market disequilibrium is the phenomenon of a speculative bubble. We present an example of using artificially intelligent agents with bounded rationality in the study of speculative bubbles.

  3. Interactions of a designed peptide with lipopolysaccharide: Bound conformation and anti-endotoxic activity

    SciTech Connect (OSTI)

    Bhunia, Anirban; Chua, Geok Lin; Domadia, Prerna N.; Warshakoon, Hemamali; Cromer, Jens R.; David, Sunil A.; Bhattacharjya, Surajit

    2008-05-09

    Designed peptides that would selectively interact with lipopolysaccharide (LPS) or endotoxin and fold into specific conformations could serve as important scaffolds toward the development of antisepsis compounds. Here, we describe solution structure of a designed amphipathic peptide, H{sub 2}N-YVKLWRMIKFIR-CONH{sub 2} (YW12D) in complex with endotoxin as determined by transferred nuclear Overhauser effect spectroscopy. The conformation of the isolated peptide is highly flexible, but undergoes a dramatic structural stabilization in the presence of LPS. Structure calculations reveal that the peptide presents two amphipathic surfaces in its bound state to LPS whereby each surface is characterized by two positive charges and a number of aromatic and/or aliphatic residues. ITC data suggests that peptide interacts with two molecules of lipid A. In activity assays, YW12D exhibits neutralization of LPS toxicity with very little hemolysis of red blood cells. Structural and functional properties of YW12D would be applicable in designing low molecular weight non-toxic antisepsis molecules.

  4. Pattern selection and super-patterns in the bounded confidence model

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

    Ben-Naim, E.; Scheel, A.

    2015-10-26

    We study pattern formation in the bounded confidence model of opinion dynamics. In this random process, opinion is quantified by a single variable. Two agents may interact and reach a fair compromise, but only if their difference of opinion falls below a fixed threshold. Starting from a uniform distribution of opinions with compact support, a traveling wave forms and it propagates from the domain boundary into the unstable uniform state. Consequently, the system reaches a steady state with isolated clusters that are separated by distance larger than the interaction range. These clusters form a quasi-periodic pattern where the sizes ofmore » the clusters and the separations between them are nearly constant. We obtain analytically the average separation between clusters L. Interestingly, there are also very small quasi-periodic modulations in the size of the clusters. Furthermore, the spatial periods of these modulations are a series of integers that follow from the continued-fraction representation of the irrational average separation L.« less

  5. Crystal structure of rhodopsin bound to arrestin by femtosecond X-ray laser

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

    Kang, Yanyong; Zhou, X. Edward; Gao, Xiang; He, Yuanzheng; Liu, Wei; Ishchenko, Andrii; Barty, Anton; White, Thomas A.; Yefanov, Oleksandr; Han, Gye Won; et al

    2015-07-22

    G-protein-coupled receptors (GPCRs) signal primarily through G proteins or arrestins. Arrestin binding to GPCRs blocks G protein interaction and redirects signalling to numerous G-protein-independent pathways. Here we report the crystal structure of a constitutively active form of human rhodopsin bound to a pre-activated form of the mouse visual arrestin, determined by serial femtosecond X-ray laser crystallography. Together with extensive biochemical and mutagenesis data, the structure reveals an overall architecture of the rhodopsin-arrestin assembly in which rhodopsin uses distinct structural elements, including transmembrane helix 7 and helix 8, to recruit arrestin. Correspondingly, arrestin adopts the pre-activated conformation, with a ~20° rotationmore » between the amino and carboxy domains, which opens up a cleft in arrestin to accommodate a short helix formed by the second intracellular loop of rhodopsin. In conclusion, this structure provides a basis for understanding GPCR-mediated arrestin-biased signalling and demonstrates the power of X-ray lasers for advancing the frontiers of structural biology.« less

  6. Crystal structure of rhodopsin bound to arrestin by femtosecond X-ray laser

    SciTech Connect (OSTI)

    Kang, Yanyong; Zhou, X. Edward; Gao, Xiang; He, Yuanzheng; Liu, Wei; Ishchenko, Andrii; Barty, Anton; White, Thomas A.; Yefanov, Oleksandr; Han, Gye Won; Xu, Qingping; de Waal, Parker W.; Ke, Jiyuan; Tan, M. H. Eileen; Zhang, Chenghai; Moeller, Arne; West, Graham M.; Pascal, Bruce D.; Van Eps, Ned; Caro, Lydia N.; Vishnivetskiy, Sergey A.; Lee, Regina J.; Suino-Powell, Kelly M.; Gu, Xin; Pal, Kuntal; Ma, Jinming; Zhi, Xiaoyong; Boutet, Sébastien; Williams, Garth J.; Messerschmidt, Marc; Gati, Cornelius; Zatsepin, Nadia A.; Wang, Dingjie; James, Daniel; Basu, Shibom; Roy-Chowdhury, Shatabdi; Conrad, Chelsie E.; Coe, Jesse; Liu, Haiguang; Lisova, Stella; Kupitz, Christopher; Grotjohann, Ingo; Fromme, Raimund; Jiang, Yi; Tan, Minjia; Yang, Huaiyu; Li, Jun; Wang, Meitian; Zheng, Zhong; Li, Dianfan; Howe, Nicole; Zhao, Yingming; Standfuss, Jörg; Diederichs, Kay; Dong, Yuhui; Potter, Clinton S.; Carragher, Bridget; Caffrey, Martin; Jiang, Hualiang; Chapman, Henry N.; Spence, John C. H.; Fromme, Petra; Weierstall, Uwe; Ernst, Oliver P.; Katritch, Vsevolod; Gurevich, Vsevolod V.; Griffin, Patrick R.; Hubbell, Wayne L.; Stevens, Raymond C.; Cherezov, Vadim; Melcher, Karsten; Xu, H. Eric

    2015-07-22

    G-protein-coupled receptors (GPCRs) signal primarily through G proteins or arrestins. Arrestin binding to GPCRs blocks G protein interaction and redirects signalling to numerous G-protein-independent pathways. Here we report the crystal structure of a constitutively active form of human rhodopsin bound to a pre-activated form of the mouse visual arrestin, determined by serial femtosecond X-ray laser crystallography. Together with extensive biochemical and mutagenesis data, the structure reveals an overall architecture of the rhodopsin-arrestin assembly in which rhodopsin uses distinct structural elements, including transmembrane helix 7 and helix 8, to recruit arrestin. Correspondingly, arrestin adopts the pre-activated conformation, with a ~20° rotation between the amino and carboxy domains, which opens up a cleft in arrestin to accommodate a short helix formed by the second intracellular loop of rhodopsin. In conclusion, this structure provides a basis for understanding GPCR-mediated arrestin-biased signalling and demonstrates the power of X-ray lasers for advancing the frontiers of structural biology.

  7. Crystal structure of the FLT3 kinase domain bound to the inhibitor quizartinib (AC220)

    SciTech Connect (OSTI)

    Zorn, Julie A.; Wang, Qi; Fujimura, Eric; Barros, Tiago; Kuriyan, John; Boggon, Titus J.

    2015-04-02

    More than 30% of acute myeloid leukemia (AML) patients possess activating mutations in the receptor tyrosine kinase FMS-like tyrosine kinase 3 or FLT3. A small-molecule inhibitor of FLT3 (known as quizartinib or AC220) that is currently in clinical trials appears promising for the treatment of AML. Here, we report the co-crystal structure of the kinase domain of FLT3 in complex with quizartinib. FLT3 with quizartinib bound adopts an “Abl-like” inactive conformation with the activation loop stabilized in the “DFG-out” orientation and folded back onto the kinase domain. This conformation is similar to that observed for the uncomplexed intracellular domain of FLT3 as well as for related receptor tyrosine kinases, except for a localized induced fit in the activation loop. The co-crystal structure reveals the interactions between quizartinib and the active site of FLT3 that are key for achieving its high potency against both wild-type FLT3 as well as a FLT3 variant observed in many AML patients. This co-complex further provides a structural rationale for quizartinib-resistance mutations.

  8. XAFS investigation of polyamidoxime-bound uranyl contests the paradigm from small molecule studies

    SciTech Connect (OSTI)

    Mayes, Richard T.; Piechowicz, Marek; Lin, Zekai; Veith, Gabriel M.; Dai, Sheng; Lin, Wenbin; Abney, C. W.; Bryantsev, V. S.

    2015-11-12

    In this study, limited resource availability and population growth have motivated interest in harvesting valuable metals from unconventional reserves, but developing selective adsorbents for this task requires structural knowledge of metal binding environments. Amidoxime polymers have been identified as the most promising platform for large-scale extraction of uranium from seawater. However, despite more than 30 years of research, the uranyl coordination environment on these adsorbents has not been positively identified. We report the first XAFS investigation of polyamidoxime-bound uranyl, with EXAFS fits suggesting a cooperative chelating model, rather than the tridentate or η2 motifs proposed by small molecule and computational studies. Samples exposed to environmental seawater also display a feature consistent with a μ2-oxo-bridged transition metal in the uranyl coordination sphere, suggesting in situ formation of a specific binding site or mineralization of uranium on the polymer surface. These unexpected findings challenge several long-held assumptions and have significant implications for development of polymer adsorbents with high selectivity.

  9. New bounded skew central difference scheme. Part 2: Application to natural convection in an eccentric annulus

    SciTech Connect (OSTI)

    Moukalled, F.; Darwish, M.

    1997-01-01

    The bounded skew central difference scheme (NVF SCDS) is used to study numerically the combined effect of vertical ({epsilon}{sub y}) and horizontal ({epsilon}{sub x}) eccentricities on natural convection in an annulus between a heated horizontal cylinder and its square enclosure. Four Rayleigh numbers (Ra = 10{sup 3}, 10{sup 4}, 10{sup 5}, and 10{sup 6}), three aspect ratios (R/L = 0.1, 0.2, and 0.3), and eccentricity values ranging from {minus}0.3 to 0.3 are considered. At constant enclosure aspect ratio, the total heat transfer increases with increasing Rayleigh number. For constant Rayleigh-number values, convection contribution to total heat transfer decreases with increasing values of R/L. For conduction-dominated flows, heat transfer increases with increasing {vert_bar}{epsilon}{sub y}{vert_bar} and/or {vert_bar}{epsilon}{sub x}{vert_bar}. For convection-dominated flows, heat transfer increases with decreasing {epsilon}{sub y} for {epsilon}{sub y} < 0, decreases with increasing {epsilon}{sub y} for {epsilon}{sub y} > 0, and decreases with decreasing {epsilon}{sub x} for {epsilon}{sub x} < 0. For the case when conduction and convection are of equal importance, there is a critical {epsilon}{sub x} for which the total heat transfer is minimum.

  10. XAFS investigation of polyamidoxime-bound uranyl contests the paradigm from small molecule studies

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

    Mayes, Richard T.; Piechowicz, Marek; Lin, Zekai; Veith, Gabriel M.; Dai, Sheng; Lin, Wenbin; Abney, C. W.; Bryantsev, V. S.

    2015-11-12

    In this study, limited resource availability and population growth have motivated interest in harvesting valuable metals from unconventional reserves, but developing selective adsorbents for this task requires structural knowledge of metal binding environments. Amidoxime polymers have been identified as the most promising platform for large-scale extraction of uranium from seawater. However, despite more than 30 years of research, the uranyl coordination environment on these adsorbents has not been positively identified. We report the first XAFS investigation of polyamidoxime-bound uranyl, with EXAFS fits suggesting a cooperative chelating model, rather than the tridentate or η2 motifs proposed by small molecule and computationalmore » studies. Samples exposed to environmental seawater also display a feature consistent with a μ2-oxo-bridged transition metal in the uranyl coordination sphere, suggesting in situ formation of a specific binding site or mineralization of uranium on the polymer surface. These unexpected findings challenge several long-held assumptions and have significant implications for development of polymer adsorbents with high selectivity.« less