National Library of Energy BETA

Sample records for hierarchical structure designed

  1. Hierarchically Structured Materials for Lithium Batteries (Journal...

    Office of Scientific and Technical Information (OSTI)

    Hierarchically Structured Materials for Lithium Batteries Citation Details In-Document Search Title: Hierarchically Structured Materials for Lithium Batteries Lithium-ion battery ...

  2. Hierarchically Structured Materials for Lithium Batteries

    SciTech Connect (OSTI)

    Xiao, Jie; Zheng, Jianming; Li, Xiaolin; Shao, Yuyan; Zhang, Jiguang

    2013-09-25

    Lithium-ion battery (LIB) is one of the most promising power sources to be deployed in electric vehicles (EV), including solely battery powered vehicles, plug-in hybrid electric vehicles, and hybrid electrical vehicles. With the increasing demand on devices of high energy densities (>500 Wh/kg) , new energy storage systems, such as lithium-oxygen (Li-O2) batteries and other emerging systems beyond the conventional LIB also attracted worldwide interest for both transportation and grid energy storage applications in recent years. It is well known that the electrochemical performances of these energy storage systems depend not only on the composition of the materials, but also on the structure of electrode materials used in the batteries. Although the desired performances characteristics of batteries often have conflict requirements on the micro/nano-structure of electrodes, hierarchically designed electrodes can be tailored to satisfy these conflict requirements. This work will review hierarchically structured materials that have been successfully used in LIB and Li-O2 batteries. Our goal is to elucidate 1) how to realize the full potential of energy materials through the manipulation of morphologies, and 2) how the hierarchical structure benefits the charge transport, promotes the interfacial properties, prolongs the electrode stability and battery lifetime.

  3. Geopolymer with hierarchically meso-/macroporous structures from reactive

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

    emulsion templating Geopolymer with hierarchically meso-/macroporous structures from reactive emulsion templating Authors: Medpelli, D., Seo, J.-M., and Seo, D.-K. Title: Geopolymer with hierarchically meso-/macroporous structures from reactive emulsion templating Source: J. Amer. Ceram. Soc. Year: 2014 Volume: 97 (1) Pages: 70-73 ABSTRACT: We present a simple synthetic route to hierarchically porous geopolymers using triglyceride oil for a reactive emulsion template. In the new synthetic

  4. Hierarchical ZnO Structures Templated with Amino Acid Based Surfactant...

    Office of Scientific and Technical Information (OSTI)

    Hierarchical ZnO Structures Templated with Amino Acid Based Surfactants Citation Details In-Document Search Title: Hierarchical ZnO Structures Templated with Amino Acid Based ...

  5. Nitrocellulose Templated Hierarchical Pore Structure in Mesoporous Thin Films

    SciTech Connect (OSTI)

    Li, Xiaohong S.; Fryxell, Glen E.; Wang, Chong M.; Young, James S.

    2006-01-01

    Over the last decade, a great deal of effort has been expended on the templated synthesis of nanoporous materials. Many different templates have been used to create this nanostructure (surfactants, polymers, latex spheres, etc.), but by far the most widely used has been micelles composed of surfactants. This is a versatile, and highly useful, synthetic method, capable of producing a wide variety of materials and structures. More recently, the synthesis of hierarchical pore structures (i.e. small pores leading to large pores) has been of great interest as a means of enhancing mass transport within these materials.[1] Such hierarchical pore structures have been made by combining surfactant templating methods with latex beads [2], by assembling as-synthesized MCM-41 particles around block co-polymer micelles, followed by crosslinking and calcination [3], by spray drying MCM-41 and MCM-48 agglomerates [4], and by using ''evaporation induced self-assembly'' [5-9].

  6. Tubular structured hierarchical mesoporous titania material derived from natural cellulosic substances and application as photocatalyst for degradation of methylene blue

    SciTech Connect (OSTI)

    Huang, Haiqing; Liu, Xiaoyan; Huang, Jianguo

    2011-11-15

    Graphical abstract: Bio-inspired, tubular structured hierarchical mesoporous titania material with high photocatalytic activity under UV light was fabricated employing natural cellulosic substance (cotton) as hard template and cetyltrimethylammonium bromide (CTAB) surfactant as soft template using a one-pot sol-gel method. Highlights: {yields} Tubular structured mesoporous titania material was fabricated by sol-gel method. {yields} The titania material faithfully recorded the hierarchical structure of the template substrate (cotton). {yields} The titania material exhibited high photocatalytic activity in decomposition of methylene blue. -- Abstract: Bio-inspired, tubular structured hierarchical mesoporous titania material was designed and fabricated employing natural cellulosic substance (cotton) as hard template and cetyltrimethylammonium bromide (CTAB) surfactant as soft template by one-pot sol-gel method. The tubular structured hierarchical mesoporous titania material processes large specific surface area (40.23 m{sup 2}/g) and shows high photocatalytic activity in the photodegradation of methylene blue under UV light irradiation.

  7. Ray tracing a three-dimensional scene using a hierarchical data structure

    DOE Patents [OSTI]

    Wald, Ingo; Boulos, Solomon; Shirley, Peter

    2012-09-04

    Ray tracing a three-dimensional scene made up of geometric primitives that are spatially partitioned into a hierarchical data structure. One example embodiment is a method for ray tracing a three-dimensional scene made up of geometric primitives that are spatially partitioned into a hierarchical data structure. In this example embodiment, the hierarchical data structure includes at least a parent node and a corresponding plurality of child nodes. The method includes a first act of determining that a first active ray in the packet hits the parent node and a second act of descending to each of the plurality of child nodes.

  8. Synthesis of multi-hierarchical structured yttria-stabilized zirconia powders and their enhanced thermophysical properties

    SciTech Connect (OSTI)

    Cao, Fengmei; Gao, Yanfeng; Chen, Hongfei; Liu, Xinling; Tang, Xiaoping; Luo, Hongjie

    2013-06-01

    Multi-hierarchical structured yttria-stabilized zirconia (YSZ) powders were successfully synthesized by a hydrothermal-calcination process. The morphology, crystallinity, and microstructure of the products were characterized by SEM, XRD, TEM, and BET. A possible formation mechanism of the unique structure formed during hydrothermal processing was also investigated. The measured thermophysical results indicated that the prepared YSZ powders had a low thermal conductivity (0.631.27 W m? K?), good short-term high-temperature stability up to 1300 C. The influence of the morphology and microstructure on their thermophysical properties was briefly discussed. The unique multi-hierarchical structure makes the prepared YSZ powders candidates for use in enhanced applications involving thermal barrier coatings. - Graphical abstract: There are many tiny pores and grain boundaries in the multi-hierarchical structured yttria-stabilized zirconia (YSZ) powders,which greatly decrease the thermal conductivities of the YSZ powders. - Highlights: Multi-hierarchical structured YSZ powders were successfully prepared. The prepared YSZ powders had a low thermal conductivity (0.631.27 W m? K?). Improved high-temperature stability had been achieved for the prepared YSZ powders. The influence of the morphology on their thermophysical properties was explored.

  9. Hierarchically structured catalysts for cascade and selective steam reforming/hydrodeoxygenation reactions

    SciTech Connect (OSTI)

    Sun, Junming; Karim, Ayman M.; Li, Xiaohong S.; Rainbolt, James E.; Kovarik, Libor; Shin, Yongsoon; Wang, Yong

    2015-09-29

    We report a hierarchically structured catalyst with steam reforming and hydrodeoxygenation functionalities being deposited in the micropores and macropores, respectively. The catalyst is highly efficient to upgrade the pyrolysis vapors of pine forest product residual, resulting in a dramatically decreased acid content and increased hydrocarbon yield without external H2 supply.

  10. Structural design considerations

    SciTech Connect (OSTI)

    Marshall, P.; Chang, B.

    1996-12-31

    This paper is one of seven presented at a special OTC session on international standards for the design of offshore platforms for earthquakes. Companion papers describe an overview of proposed ISO provisions, seismic exposure, foundation design, performance characteristics, a site-specific example, and probability-based LRFD. The focus of this paper is upon results of interest to structural designers, such as: simplified load and resistance factors; lifetime reliability estimates; ductility analysis using API jolts; and example North Sea application.

  11. HIERARCHICAL STRUCTURE OF MAGNETOHYDRODYNAMIC TURBULENCE IN POSITION-POSITION-VELOCITY SPACE

    SciTech Connect (OSTI)

    Burkhart, Blakesley; Lazarian, A.; Goodman, Alyssa; Rosolowsky, Erik

    2013-06-20

    Magnetohydrodynamic turbulence is able to create hierarchical structures in the interstellar medium (ISM) that are correlated on a wide range of scales via the energy cascade. We use hierarchical tree diagrams known as dendrograms to characterize structures in synthetic position-position-velocity (PPV) emission cubes of isothermal magnetohydrodynamic turbulence. We show that the structures and degree of hierarchy observed in PPV space are related to the presence of self-gravity and the global sonic and Alfvenic Mach numbers. Simulations with higher Alfvenic Mach number, self-gravity and supersonic flows display enhanced hierarchical structure. We observe a strong dependency on the sonic and Alfvenic Mach numbers and self-gravity when we apply the statistical moments (i.e., mean, variance, skewness, kurtosis) to the leaf and node distribution of the dendrogram. Simulations with self-gravity, larger magnetic field and higher sonic Mach number have dendrogram distributions with higher statistical moments. Application of the dendrogram to three-dimensional density cubes, also known as position-position-position (PPP) cubes, reveals that the dominant emission contours in PPP and PPV are related for supersonic gas but not for subsonic. We also explore the effects of smoothing, thermal broadening, and velocity resolution on the dendrograms in order to make our study more applicable to observational data. These results all point to hierarchical tree diagrams as being a promising additional tool for studying ISM turbulence and star forming regions for obtaining information on the degree of self-gravity, the Mach numbers and the complicated relationship between PPV and PPP data.

  12. Metal segregation in hierarchically structured cathode materials for high-energy lithium batteries

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

    Lin, Feng; Xin, Huolin L.; Nordlund, Dennis; Li, Yuyi; Quan, Matthew K.; Cheng, Lei; Weng, Tsu -Chien; Liu, Yijin; Doeff, Marca M.

    2016-01-11

    Controlling surface and interfacial properties of battery materials is key to improving performance in rechargeable Li-ion devices. Surface reconstruction from a layered to a rock salt structure in metal oxide cathode materials is commonly observed and results in poor high-voltage cycling performance, impeding attempts to improve energy density. Hierarchically structured LiNi0.4Mn0.4Co0.2O2 (NMC-442) spherical powders, made by spray pyrolysis, exhibit local elemental distribution gradients that deviate from the global NMC-442 composition; specifically, they are Ni-rich and Mn-poor at particle surfaces. These materials demonstrate improved Coulombic efficiencies, discharge capacities, and high-voltage capacity retention in lithium half-cell configurations. The subject powders show superiormore » resistance against surface reconstruction due to the tailored surface chemistry, compared to conventional NMC-442 materials. This paves the way towards the development of a new generation of robust and stable high-energy NMC cathodes for Li-ion batteries.« less

  13. Hierarchical diffusion

    SciTech Connect (OSTI)

    Bachas, C.P.

    1988-02-01

    We review the solution and properties of the diffusion equation in a hierarchical or ultrametric space. 11 refs.

  14. Low-Energy Parking Structure Design (Brochure)

    SciTech Connect (OSTI)

    Not Available

    2013-01-01

    This guide provides design teams with best practices for parking structure energy efficiency in the form of goals for each design aspect that affects energy use.

  15. A novel 3D structure composed of strings of hierarchical TiO{sub 2} spheres formed on TiO{sub 2} nanobelts with high photocatalytic properties

    SciTech Connect (OSTI)

    Jiang, Yongjian; Li, Meicheng; Song, Dandan; Li, Xiaodan; Yu, Yue

    2014-03-15

    A novel hierarchical titanium dioxide (TiO{sub 2}) composite nanostructure with strings of anatase TiO{sub 2} hierarchical micro-spheres and rutile nanobelts framework (TiO{sub 2} HSN) is successfully synthesized via a one-step hydrothermal method. Particularly, the strings of hierarchical spheres are assembled by very thin TiO{sub 2} nanosheets, which are composed of highly crystallized anatase nanocrystals. Meanwhile, the HSN has a large surface area of 191 m{sup 2}/g, which is about 3 times larger than Degussa P25. More importantly, the photocatalytic activity of HSN and P25 were evaluated by the photocatalytic oxidation decomposition of methyl orange (MO) under UV light illumination, and the TiO{sub 2} HSN shows enhanced photocatalytic activity compared with Degussa P25, as result of its continuous hierarchical structures, special conductive channel and large specific surface area. With these features, the hierarchical TiO{sub 2} may have more potential applications in the fields of dye-sensitized solar cells and lithium ion batteries. -- Graphical abstract: Novel TiO{sub 2} with anatase micro-spheres and rutile nanobelts is synthesized. Enhanced photocatalysis is attributed to hierarchical structures (3D spheres), conductive channel (1D nanobelts) and large specific surface area (2D nanosheet). Highlights: • The novel TiO{sub 2} nanostructure (HSN) is fabricated for the first time. • HSN is composed of strings of anatase hierarchical spheres and rutile nanobelt. • HSN presents a larger S{sub BET} of 191 m{sup 2}/g, 3 times larger than the Degussa P25 (59 m{sup 2}/g). • HSN owns three kinds of dimensional TiO{sub 2} (1D, 2D and 3D) simultaneously. • HSN exhibits better photocatalytic performance compared with Degussa P25.

  16. Microparticles with hierarchical porosity

    DOE Patents [OSTI]

    Petsev, Dimiter N; Atanassov, Plamen; Pylypenko, Svitlana; Carroll, Nick; Olson, Tim

    2012-12-18

    The present disclosure provides oxide microparticles with engineered hierarchical porosity and methods of manufacturing the same. Also described are structures that are formed by templating, impregnating, and/or precipitating the oxide microparticles and method for forming the same. Suitable applications include catalysts, electrocatalysts, electrocatalysts support materials, capacitors, drug delivery systems, sensors and chromatography.

  17. Characterization of the effects of x-ray irradiation on the hierarchical structure and mechanical properties of human cortical bone

    SciTech Connect (OSTI)

    Barth, Holly; Zimmermann, Elizabeth; Schaible, Eric; Tang, Simon; Alliston, Tamara; Ritchie, Robert

    2011-08-19

    Bone comprises a complex structure of primarily collagen, hydroxyapatite and water, where each hierarchical structural level contributes to its strength, ductility and toughness. These properties, however, are degraded by irradiation, arising from medical therapy or bone-allograft sterilization. We provide here a mechanistic framework for how irradiation affects the nature and properties of human cortical bone over a range of characteristic (nano to macro) length-scales, following x-ray exposures up to 630 kGy. Macroscopically, bone strength, ductility and fracture resistance are seen to be progressively degraded with increasing irradiation levels. At the micron-scale, fracture properties, evaluated using in-situ scanning electron microscopy and synchrotron x-ray computed micro-tomography, provide mechanistic information on how cracks interact with the bone-matrix structure. At sub-micron scales, strength properties are evaluated with in-situ tensile tests in the synchrotron using small-/wide-angle x-ray scattering/diffraction, where strains are simultaneously measured in the macroscopic tissue, collagen fibrils and mineral. Compared to healthy bone, results show that the fibrillar strain is decreased by ~40% following 70 kGy exposures, consistent with significant stiffening and degradation of the collagen. We attribute the irradiation-induced deterioration in mechanical properties to mechanisms at multiple length-scales, including changes in crack paths at micron-scales, loss of plasticity from suppressed fibrillar sliding at sub-micron scales, and the loss and damage of collagen at the nano-scales, the latter being assessed using Raman and Fourier-Transform-Infrared spectroscopy and a fluorometric assay.

  18. Synthesis of BiOI flowerlike hierarchical structures toward photocatalytic reduction of CO{sub 2} to CH{sub 4}

    SciTech Connect (OSTI)

    Zhang, Guojie Su, Aiting; Qu, Jiangwen; Xu, Ying

    2014-07-01

    BiOI can be used for photocatalytic reduction of CO{sub 2} into hydrocarbon fuels under sunlight. - Highlights: Room temperature synthesis of BiOI flowerlike hierarchical structures. BiOI can be used for photocatalytic reduction of CO{sub 2} into hydrocarbon fuels under sunlight. The photocatalytic activity of BiOI is higher than that of P25 TiO{sub 2}. - Abstract: BiOI flowerlike hierarchical structure was synthesized by the direct hydrolysis method hydrolysis at room temperature in the presence of polyvinyl pyrrolidone. As-synthesized BiOI was characterized by powder X-ray diffraction, UVvis diffuse reflectance spectra, X-ray photoelectron spectroscopy spectra, scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. It is a facile way to obtain BiOI flowerlike hierarchical structure photocatalyst for photocatalytic reduction of CO{sub 2} into hydrocarbon fuels under simulated sunlight irradiation without cocatalyst. And the photocatalytic activity of as-synthesized BiOI is higher than that of P25 TiO{sub 2} and bulk BiOI.

  19. Robust carbon monolith having hierarchical porosity

    DOE Patents [OSTI]

    Dai, Sheng; Guiochon, Georges A; Liang, Chengdu

    2014-01-14

    A carbon monolith includes a robust carbon monolith characterized by a skeleton size of at least 100 nm, and a hierarchical pore structure having macropores and mesopores.

  20. Robust carbon monolith having hierarchical porosity

    DOE Patents [OSTI]

    Dai, Sheng; Guiohon, Georges A; Liang, Chengdu

    2013-02-05

    A carbon monolith includes a robust carbon monolith characterized by a skeleton size of at least 100 nm, and a hierarchical pore structure having macropores and mesopores.

  1. Robust carbon monolith having hierarchical porosity

    DOE Patents [OSTI]

    Dai, Sheng [Knoxville, TN; Guiochon, Georges A. [Farragut, TN; Liang, Chengdu [Knoxville, TN

    2008-11-11

    A carbon monolith includes a robust carbon monolith characterized by a skeleton size of at least 100 nm, and a hierarchical pore structure having macropores and mesopores.

  2. Robust carbon monolith having hierarchical porosity

    DOE Patents [OSTI]

    Dai, Sheng; Guiochon, Georges A; Liang, Chengdu

    2011-02-22

    A carbon monolith includes a robust carbon monolith characterized by a skeleton size of at least 100 nm, and a hierarchical pore structure having macropores and mesopores.

  3. Designing of Metallic Photonic Structures and Applications

    SciTech Connect (OSTI)

    Yong-Sung Kim

    2006-08-09

    In this thesis our main interest has been to investigate metallic photonic crystal and its applications. We explained how to solve a periodic photonic structure with transfer matrix method and when and how to use modal expansion method. Two different coating methods were introduced, modifying a photonic structure's intrinsic optical properties and rigorous calculation results are presented. Two applications of metallic photonic structures are introduced. For thermal emitter, we showed how to design and find optimal structure. For conversion efficiency increasing filter, we calculated its efficiency and the way to design it. We presented the relation between emitting light spectrum and absorption and showed the material and structural dependency of the absorption spectrum. By choosing a proper base material and structural parameters, we can design a selective emitter at a certain region we are interested in. We have developed a theoretical model to analyze a blackbody filament enclosed by a metallic mesh which can increase the efficiency of converting a blackbody radiation to visible light. With this model we found that a square lattice metallic mesh enclosing a filament might increase the efficiency of incandescent lighting sources. Filling fraction and thickness dependency were examined and presented. Combining these two parameters is essential to achieve the maximum output result.

  4. Design Optimization of Structural Health Monitoring Systems

    SciTech Connect (OSTI)

    Flynn, Eric B.

    2014-03-06

    Sensor networks drive decisions. Approach: Design networks to minimize the expected total cost (in a statistical sense, i.e. Bayes Risk) associated with making wrong decisions and with installing maintaining and running the sensor network itself. Search for optimal solutions using Monte-Carlo-Sampling-Adapted Genetic Algorithm. Applications include structural health monitoring and surveillance.

  5. AHTR Mechanical, Structural, and Neutronic Preconceptual Design

    SciTech Connect (OSTI)

    Varma, V.K.; Holcomb, D.E.; Peretz, F.J.; Bradley, E.C.; Ilas, D.; Qualls, A.L.; Zaharia, N.M.

    2012-09-15

    This report provides an overview of the mechanical, structural, and neutronic aspects of the Advanced High Temperature Reactor (AHTR) design concept. The AHTR is a design concept for a large output Fluoride salt cooled High-temperature Reactor (FHR) that is being developed to enable evaluation of the technology hurdles remaining to be overcome prior to FHRs becoming an option for commercial reactor deployment. This report documents the incremental AHTR design maturation performed over the past year and is focused on advancing the design concept to a level of a functional, self-consistent system. The reactor concept development remains at a preconceptual level of maturity. While the overall appearance of an AHTR design is anticipated to be similar to the current concept, optimized dimensions will differ from those presented here. The AHTR employs plate type coated particle fuel assemblies with rapid, off-line refueling. Neutronic analysis of the core has confirmed the viability of a 6-month two-batch cycle with 9 wt. % enriched uranium fuel. Refueling is intended to be performed automatically under visual guidance using dedicated robotic manipulators. The report includes a preconceptual design of the manipulators, the fuel transfer system, and the used fuel storage system. The present design intent is for used fuel to be stored inside of containment for at least six months and then transferred to local dry wells for intermediate term, on-site storage. The mechanical and structural concept development effort has included an emphasis on transportation and constructability to minimize construction costs and schedule. The design intent is that all components be factory fabricated into rail transportable modules that are assembled into subsystems at an on-site workshop prior to being lifted into position using a heavy-lift crane in an open-top style construction. While detailed accident identification and response sequence analysis has yet to be performed, the design

  6. AHTR Mechanical, Structural, And Neutronic Preconceptual Design

    SciTech Connect (OSTI)

    Varma, Venugopal Koikal; Holcomb, David Eugene; Peretz, Fred J; Bradley, Eric Craig; Ilas, Dan; Qualls, A L; Zaharia, Nathaniel M

    2012-10-01

    This report provides an overview of the mechanical, structural, and neutronic aspects of the Advanced High Temperature Reactor (AHTR) design concept. The AHTR is a design concept for a large output Fluoride salt cooled High-temperature Reactor (FHR) that is being developed to enable evaluation of the technology hurdles remaining to be overcome prior to FHRs becoming a commercial reactor class. This report documents the incremental AHTR design maturation performed over the past year and is focused on advancing the design concept to a level of a functional, self-consistent system. The AHTR employs plate type coated particle fuel assemblies with rapid, off-line refueling. Neutronic analysis of the core has confirmed the viability of a 6-month 2-batch cycle with 9 weight-percent enriched uranium fuel. Refueling is intended to be performed automatically under visual guidance using dedicated robotic manipulators. The present design intent is for used fuel to be stored inside of containment for at least 6 months and then transferred to local dry wells for intermediate term, on-site storage. The mechanical and structural concept development effort has included an emphasis on transportation and constructability to minimize construction costs and schedule. The design intent is that all components be factory fabricated into rail transportable modules that are assembled into subsystems at an on-site workshop prior to being lifted into position using a heavy-lift crane in an open-top style construction. While detailed accident identification and response sequence analysis has yet to be performed, the design concept incorporates multiple levels of radioactive material containment including fully passive responses to all identified design basis or non-very-low frequency beyond design basis accidents. Key building design elements include: 1) below grade siting to minimize vulnerability to aircraft impact, 2) multiple natural circulation decay heat rejection chimneys, 3) seismic

  7. Structural Design Challenges in Design Certification Applications for New Reactors

    SciTech Connect (OSTI)

    Miranda, M.; Braverman, J.; Wei, X.; Hofmayer, C.; Xu, J.

    2011-07-17

    The licensing framework established by the U.S. Nuclear Regulatory Commission under Title 10 of the Code of Federal Regulations (10 CFR) Part 52, “Licenses, Certifications, and Approvals for Nuclear Power Plants,” provides requirements for standard design certifications (DCs) and combined license (COL) applications. The intent of this process is the early reso- lution of safety issues at the DC application stage. Subsequent COL applications may incorporate a DC by reference. Thus, the COL review will not reconsider safety issues resolved during the DC process. However, a COL application that incorporates a DC by reference must demonstrate that relevant site-specific de- sign parameters are confined within the bounds postulated by the DC, and any departures from the DC need to be justified. This paper provides an overview of structural design chal- lenges encountered in recent DC applications under the 10 CFR Part 52 process, in which the authors have participated as part of the safety review effort.

  8. Final Report of Optimization Algorithms for Hierarchical Problems, with Applications to Nanoporous Materials

    SciTech Connect (OSTI)

    Nash, Stephen G.

    2013-11-11

    The research focuses on the modeling and optimization of nanoporous materials. In systems with hierarchical structure that we consider, the physics changes as the scale of the problem is reduced and it can be important to account for physics at the fine level to obtain accurate approximations at coarser levels. For example, nanoporous materials hold promise for energy production and storage. A significant issue is the fabrication of channels within these materials to allow rapid diffusion through the material. One goal of our research is to apply optimization methods to the design of nanoporous materials. Such problems are large and challenging, with hierarchical structure that we believe can be exploited, and with a large range of important scales, down to atomistic. This requires research on large-scale optimization for systems that exhibit different physics at different scales, and the development of algorithms applicable to designing nanoporous materials for many important applications in energy production, storage, distribution, and use. Our research has two major research thrusts. The first is hierarchical modeling. We plan to develop and study hierarchical optimization models for nanoporous materials. The models have hierarchical structure, and attempt to balance the conflicting aims of model fidelity and computational tractability. In addition, we analyze the general hierarchical model, as well as the specific application models, to determine their properties, particularly those properties that are relevant to the hierarchical optimization algorithms. The second thrust was to develop, analyze, and implement a class of hierarchical optimization algorithms, and apply them to the hierarchical models we have developed. We adapted and extended the optimization-based multigrid algorithms of Lewis and Nash to the optimization models exemplified by the hierarchical optimization model. This class of multigrid algorithms has been shown to be a powerful tool for

  9. Guide to FEMP-Designated Parking Structure Lighting

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

    National Renewable Energy Laboratory's parking structure utilizes many measures to achieve a parking structure that uses 90% less energy than the baseline energy code. TABLE OF CONTENTS 1 INTRODUCTION * FEMP-DESIGNATED PRODUCTS * ENERGY EFFICIENCY METRICS 3 DESIGN PROCESS * STEP-BY-STEP OVERVIEW 6 COMPONENTS OF THE DESIGN * BUILDING DESIGN CONSIDERATIONS * MATERIAL SELECTION * LIGHTING DESIGN CONSIDERATIONS * LUMINAIRE DISTRIBUTION * COLOR QUALITIES * LUMINAIRE LAYOUT 13 PARKING STRUCTURE

  10. Ferritic Alloys with Extreme Creep Resistance via Coherent Hierarchical Precipitates

    SciTech Connect (OSTI)

    Song, Gian; Sun, Zhiqian; Li, Lin; Xu, Xiandong; Rawlings, Michael; Liebscher, Christian H.; Clausen, Bjørn; Poplawsky, Jonathan; Leonard, Donovan N.; Huang, Shenyan; Teng, Zhenke; Liu, Chain T.; Asta, Mark D.; Gao, Yanfei; Dunand, David C.; Ghosh, Gautam; Chen, Mingwei; Fine, Morris E.; Liaw, Peter K.

    2015-11-09

    There have been numerous efforts to develop creep-resistant materials strengthened by incoherent particles at high temperatures and stresses in response to future energy needs for steam turbines in thermal-power plants. However, the microstructural instability of the incoherent-particle-strengthened ferritic steels limits their application to temperatures below 900 K. Here, we report a novel ferritic alloy with the excellent creep resistance enhanced by coherent hierarchical precipitates, using the integrated experimental (transmission-electron microscopy/scanning-transmission-electron microscopy, in-situ neutron diffraction, and atom-probe tomography) and theoretical (crystal-plasticity finite-element modeling) approaches. This alloy is strengthened by nano-scaled L21-Ni2TiAl (Heusler phase)-based precipitates, which themselves contain coherent nano-scaled B2 zones. These coherent hierarchical precipitates are uniformly distributed within the Fe matrix. Our hierarchical structure material exhibits the superior creep resistance at 973 K in terms of the minimal creep rate, which is four orders of magnitude lower than that of conventional ferritic steels. These results provide a new alloy-design strategy using the novel concept of hierarchical precipitates and the fundamental science for developing creep-resistant ferritic alloys. Finally, the present research will broaden the applications of ferritic alloys to higher temperatures.

  11. Ferritic Alloys with Extreme Creep Resistance via Coherent Hierarchical Precipitates

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

    Song, Gian; Sun, Zhiqian; Li, Lin; Xu, Xiandong; Rawlings, Michael; Liebscher, Christian H.; Clausen, Bjørn; Poplawsky, Jonathan; Leonard, Donovan N.; Huang, Shenyan; et al

    2015-11-09

    There have been numerous efforts to develop creep-resistant materials strengthened by incoherent particles at high temperatures and stresses in response to future energy needs for steam turbines in thermal-power plants. However, the microstructural instability of the incoherent-particle-strengthened ferritic steels limits their application to temperatures below 900 K. Here, we report a novel ferritic alloy with the excellent creep resistance enhanced by coherent hierarchical precipitates, using the integrated experimental (transmission-electron microscopy/scanning-transmission-electron microscopy, in-situ neutron diffraction, and atom-probe tomography) and theoretical (crystal-plasticity finite-element modeling) approaches. This alloy is strengthened by nano-scaled L21-Ni2TiAl (Heusler phase)-based precipitates, which themselves contain coherent nano-scaled B2 zones.more » These coherent hierarchical precipitates are uniformly distributed within the Fe matrix. Our hierarchical structure material exhibits the superior creep resistance at 973 K in terms of the minimal creep rate, which is four orders of magnitude lower than that of conventional ferritic steels. These results provide a new alloy-design strategy using the novel concept of hierarchical precipitates and the fundamental science for developing creep-resistant ferritic alloys. Finally, the present research will broaden the applications of ferritic alloys to higher temperatures.« less

  12. Towards Breakthroughs in Protein Structure Calculation and Design | Argonne

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

    Leadership Computing Facility Technology for designing any arbitrary protein structures from scratch is essential for engineering desired functional proteins for materials and therapeutics. We've discovered the fundamental rules for creating ideal protein structures stabilized by completely consistent local and non-local interactions. Guided by the rules, we designed the novel protein structures of five different topologies computationally (upper structures) using Rosetta@HOME. The designs

  13. Hierarchical Heterogeneity at the CeO x –TiO 2 Interface: Electronic and Geometric Structural Influence on the Photocatalytic Activity of Oxide on Oxide Nanostructures

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

    Luo, Si; Nguyen-Phan, Thuy-Duong; Johnston-Peck, Aaron C.; Barrio, Laura; Sallis, Shawn; Arena, Dario A.; Kundu, Shankhamala; Xu, Wenqian; Piper, Louis F. J.; Stach, Eric A.; et al

    2015-01-13

    Mixed oxide interfaces are critical for delivering active components of demanding catalytic processes such as the photo-catalytic splitting of water. We have studied CeOxTiO₂ catalysts with low ceria loadings of 1 wt%, 3 wt% and 6 wt% that were prepared with wet impregnation methods to favor a strong interaction between CeOx and TiO₂. In these materials the interfaces between CeOx-TiO₂ have been sequentially loaded (1%, 3% and 6%), with and without Pt (0.5 wt%). The structure and properties of the catalysts were characterized using several X-ray and electron based techniques including XRD, XPS, UPS, NEXAFS, UV-Vis and HR-STEM/STEM-EELS, to unravelmore » the local morphology, bulk structure, surface states and electronic structure. The combination of all these techniques allow us to analyze in a systematic way the complete structural and electronic properties that prevail at the CeOx-TiO₂ interface. Fluorite structured nano crystallites of ceria on anatase-structured titania were identified by both XRD and NEXAFS. A sequential increasing of the CeOx loading led to the formation of clusters, then plates and finally nano particles in a hierarchical manner on the TiO₂ support. The electronic structures of these catalysts indicate that the interaction between TiO₂ and CeO₂ is closely related to the local morphology of nanostructured CeO₂. Ce³⁺ cations were detected at the surface of CeO₂ and at the interface of the two oxides. In addition, the titania is perturbed by the interaction with ceria and also with Pt. The photocatalytic activity for the splitting of H₂O using UV light was measured for these materials and correlated with our understanding of the electronic and structural properties. Optimal catalytic performance and photo response results were found for the 1 wt% CeOx-TiO₂ catalyst where low dimensional geometry of the ceria provided ideal electronic and geometrical properties. The structural and electronic properties of the interface

  14. Hierarchical heterogeneity at the CeOx-TiO? interface: Electronic and geometric structural influence on the photocatalytic activity of oxide on oxide nanostructures

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

    None

    2015-01-13

    Mixed oxide interfaces are critical for delivering active components of demanding catalytic processes such as the photo-catalytic splitting of water. We have studied CeOxTiO? catalysts with low ceria loadings of 1 wt%, 3 wt% and 6 wt% that were prepared with wet impregnation methods to favor a strong interaction between CeOx and TiO?. In these materials the interfaces between CeOx-TiO? have been sequentially loaded (1%, 3% and 6%), with and without Pt (0.5 wt%). The structure and properties of the catalysts were characterized using several X-ray and electron based techniques including XRD, XPS, UPS, NEXAFS, UV-Vis and HR-STEM/STEM-EELS, to unravelmorethe local morphology, bulk structure, surface states and electronic structure. The combination of all these techniques allow us to analyze in a systematic way the complete structural and electronic properties that prevail at the CeOx-TiO? interface. Fluorite structured nano crystallites of ceria on anatase-structured titania were identified by both XRD and NEXAFS. A sequential increasing of the CeOx loading led to the formation of clusters, then plates and finally nano particles in a hierarchical manner on the TiO? support. The electronic structures of these catalysts indicate that the interaction between TiO? and CeO? is closely related to the local morphology of nanostructured CeO?. Ce? cations were detected at the surface of CeO? and at the interface of the two oxides. In addition, the titania is perturbed by the interaction with ceria and also with Pt. The photocatalytic activity for the splitting of H?O using UV light was measured for these materials and correlated with our understanding of the electronic and structural properties. Optimal catalytic performance and photo response results were found for the 1 wt% CeOx-TiO? catalyst where low dimensional geometry of the ceria provided ideal electronic and geometrical properties. The structural and electronic properties of the interface were critical for the

  15. Hierarchical Nanoceramics for Industrial Process Sensors

    SciTech Connect (OSTI)

    Ruud, James, A.; Brosnan, Kristen, H.; Striker, Todd; Ramaswamy, Vidya; Aceto, Steven, C.; Gao, Yan; Willson, Patrick, D.; Manoharan, Mohan; Armstrong, Eric, N., Wachsman, Eric, D.; Kao, Chi-Chang

    2011-07-15

    This project developed a robust, tunable, hierarchical nanoceramics materials platform for industrial process sensors in harsh-environments. Control of material structure at multiple length scales from nano to macro increased the sensing response of the materials to combustion gases. These materials operated at relatively high temperatures, enabling detection close to the source of combustion. It is anticipated that these materials can form the basis for a new class of sensors enabling widespread use of efficient combustion processes with closed loop feedback control in the energy-intensive industries. The first phase of the project focused on materials selection and process development, leading to hierarchical nanoceramics that were evaluated for sensing performance. The second phase focused on optimizing the materials processes and microstructures, followed by validation of performance of a prototype sensor in a laboratory combustion environment. The objectives of this project were achieved by: (1) synthesizing and optimizing hierarchical nanostructures; (2) synthesizing and optimizing sensing nanomaterials; (3) integrating sensing functionality into hierarchical nanostructures; (4) demonstrating material performance in a sensing element; and (5) validating material performance in a simulated service environment. The project developed hierarchical nanoceramic electrodes for mixed potential zirconia gas sensors with increased surface area and demonstrated tailored electrocatalytic activity operable at high temperatures enabling detection of products of combustion such as NOx close to the source of combustion. Methods were developed for synthesis of hierarchical nanostructures with high, stable surface area, integrated catalytic functionality within the structures for gas sensing, and demonstrated materials performance in harsh lab and combustion gas environments.

  16. Hierarchical Analysis of the Omega Ontology

    SciTech Connect (OSTI)

    Joslyn, Cliff A.; Paulson, Patrick R.

    2009-12-01

    Initial delivery for mathematical analysis of the Omega Ontology. We provide an analysis of the hierarchical structure of a version of the Omega Ontology currently in use within the US Government. After providing an initial statistical analysis of the distribution of all link types in the ontology, we then provide a detailed order theoretical analysis of each of the four main hierarchical links present. This order theoretical analysis includes the distribution of components and their properties, their parent/child and multiple inheritance structure, and the distribution of their vertical ranks.

  17. Design and Analysis of Muon Beam Stop Support Structures

    SciTech Connect (OSTI)

    Okafor, Udenna

    2015-01-01

    The primary objective of this thesis is to design and analyze support structures to be used in the installation, test and final positioning of the MBS throughout the life of the Mu2e experiment. There several requirements for the MBS imposed by both the scope of the experiment and, other components within the DS bore. The functions of the MBS are: 1. To limit the induced rates in the Tracker, the Calorimeter and the Cosmic Ray Veto due to backsplash-and-secondary interactions, and 2. To reduce radiation levels external to the Detector solenoid. The structures used in supporting the MBS will also adhere to requirements imposed by its functions. These requirements are critical to the support structures and affect design decisions. Other requirements critical to the design are imposed by the weight, positional tolerance and assembly procedure of the MBS, and also, the magnetic field and vacuum dose rate of the DS bore. A detailed breakdown of how each requirement affects the structural design can be found in chapter 2. Chapter 3 describes the design of each support structure and its attachment to the MBS while chapter 4 describes the results from structural analysis of the support structures. Chapter 5 describes evaluation for the design through testing and calculations while the conclusion in chapter 6 reports the current status at the time of this thesis submission with a plan for future work to be completed until final design and installation.

  18. NRT Rotor Structural / Aeroelastic Analysis for the Preliminary Design Review

    SciTech Connect (OSTI)

    Ennis, Brandon Lee; Paquette, Joshua A.

    2015-10-01

    This document describes the initial structural design for the National Rotor Testbed blade as presented during the preliminary design review at Sandia National Laboratories on October 28- 29, 2015. The document summarizes the structural and aeroelastic requirements placed on the NRT rotor for satisfactory deployment at the DOE/SNL SWiFT experimental facility to produce high-quality datasets for wind turbine model validation. The method and result of the NRT blade structural optimization is also presented within this report, along with analysis of its satisfaction of the design requirements.

  19. Inward Lithium-Ion Breathing of Hierarchically Porous Silicon Anodes

    SciTech Connect (OSTI)

    Xiao, Qiangfeng; Gu, Meng; Yang, Hui; Li, Bing; Zhang, Cunman; Liu, Yang; Liu, Fang; Dai, Fang; Yang, Li; Liu, Zhongyi; Xiao, Xingcheng; Liu, Gao; Zhao, Peng; Zhang, Sulin; Wang, Chong M.; Lu, Yunfeng; Cai, Mei

    2015-11-05

    Silicon has been identified as one of the most promising candidates as anode for high performance lithium-ion batteries. The key challenge for Si anodes is the large volume change induced chemomechanical fracture and subsequent rapid capacity fading upon cyclic charge and discharge. Improving capacity retention thus critically relies on smart accommodation of the volume changes through nanoscale structural design. In this work, we report a novel fabrication method for hierarchically porous Si nanospheres (hp-SiNSs), which consist of a porous shell and a hollow core. Upon charge/discharge cycling, the hp-SiNSs accommodate the volume change through reversible inward expansion/contraction with negligible particle-level outward expansion. Our mechanics analysis revealed that such a unique volume-change accommodation mechanism is enabled by the much stiffer modulus of the lithiated layer than the unlithiated porous layer and the low flow stress of the porous structure. Such inward expansion shields the hp-SiNSs from fracture, opposite to the outward expansion in solid Si during lithiation. Lithium ion battery assembled with this new nanoporous material exhibits high capacity, high power, long cycle life and high coulombic efficiency, which is superior to the current commercial Si-based anode materials. The low cost synthesis approach reported here provides a new avenue for the rational design of hierarchically porous structures with unique materials properties.

  20. Inward Lithium-Ion Breathing of Hierarchically Porous Silicon Anodes

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

    Xiao, Qiangfeng; Gu, Meng; Yang, Hui; Li, Bing; Zhang, Cunman; Liu, Yang; Liu, Fang; Dai, Fang; Yang, Li; Liu, Zhongyi; et al

    2015-11-05

    Silicon has been identified as one of the most promising candidates as anode for high performance lithium-ion batteries. The key challenge for Si anodes is the large volume change induced chemomechanical fracture and subsequent rapid capacity fading upon cyclic charge and discharge. Improving capacity retention thus critically relies on smart accommodation of the volume changes through nanoscale structural design. In this work, we report a novel fabrication method for hierarchically porous Si nanospheres (hp-SiNSs), which consist of a porous shell and a hollow core. Upon charge/discharge cycling, the hp-SiNSs accommodate the volume change through reversible inward expansion/contraction with negligible particle-levelmore » outward expansion. Our mechanics analysis revealed that such a unique volume-change accommodation mechanism is enabled by the much stiffer modulus of the lithiated layer than the unlithiated porous layer and the low flow stress of the porous structure. Such inward expansion shields the hp-SiNSs from fracture, opposite to the outward expansion in solid Si during lithiation. Lithium ion battery assembled with this new nanoporous material exhibits high capacity, high power, long cycle life and high coulombic efficiency, which is superior to the current commercial Si-based anode materials. We find the low cost synthesis approach reported here provides a new avenue for the rational design of hierarchically porous structures with unique materials properties.« less

  1. Inward Lithium-Ion Breathing of Hierarchically Porous Silicon Anodes

    SciTech Connect (OSTI)

    Xiao, Qiangfeng; Gu, Meng; Yang, Hui; Li, Bing; Zhang, Cunman; Liu, Yang; Liu, Fang; Dai, Fang; Yang, Li; Liu, Zhongyi; Xiao, Xingcheng; Liu, Gao; Zhao, Peng; Zhang, Sulin; Wang, Chong M.; Lu, Yunfeng; Cai, Mei

    2015-11-05

    Silicon has been identified as one of the most promising candidates as anode for high performance lithium-ion batteries. The key challenge for Si anodes is the large volume change induced chemomechanical fracture and subsequent rapid capacity fading upon cyclic charge and discharge. Improving capacity retention thus critically relies on smart accommodation of the volume changes through nanoscale structural design. In this work, we report a novel fabrication method for hierarchically porous Si nanospheres (hp-SiNSs), which consist of a porous shell and a hollow core. Upon charge/discharge cycling, the hp-SiNSs accommodate the volume change through reversible inward expansion/contraction with negligible particle-level outward expansion. Our mechanics analysis revealed that such a unique volume-change accommodation mechanism is enabled by the much stiffer modulus of the lithiated layer than the unlithiated porous layer and the low flow stress of the porous structure. Such inward expansion shields the hp-SiNSs from fracture, opposite to the outward expansion in solid Si during lithiation. Lithium ion battery assembled with this new nanoporous material exhibits high capacity, high power, long cycle life and high coulombic efficiency, which is superior to the current commercial Si-based anode materials. We find the low cost synthesis approach reported here provides a new avenue for the rational design of hierarchically porous structures with unique materials properties.

  2. Towards Breakthroughs in Protein Structure Calculation and Design | Argonne

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

    Leadership Computing Facility Towards Breakthroughs in Protein Structure Calculation and Design PI Name: David Baker PI Email: dabaker@u.washington.edu Institution: University of Washington Allocation Program: INCITE Allocation Hours at ALCF: 33,000,000 Year: 2012 Research Domain: Computer Science The computational resources from this INCITE award are being applied toward high-resolution protein structure calculation, de-novo protein-protein interface design for therapeutic applications, and

  3. New flow-through mudmat design for Heidrun subsea structure

    SciTech Connect (OSTI)

    Lieng, J.T.; Bjoergen, H.P.

    1995-12-01

    Permanent or temporary subsea structures that require some initial or frequent on-bottom relocation need an effective mudmat release system. This is necessary in order to avoid problems that may arise due to pressure differences at the mudmat/soil interface. Through detail engineering work performed for the development of subsea installations at the Heidrun Field off the Norwegian coast, a novel mudmat design has been conceived that enables water to flow freely through the mudmat top without sacrificing overall stability or structural integrity. This was accomplished by integrating geotextiles and expanded steel mesh for support into the design. The design permits structure installation and removal keeping hydrodynamic forces, soil resistance and disturbance of the seabed sediments to a minimum. Hence, subsea dynamic behavior is more favorable reducing structural stresses, relocation time and the necessary lifting capacity of the surface vessel as compared to earlier solutions.

  4. Structure-Based Design of Functional Amyloid Materials

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

    Li, Dan; Jones, Eric M.; Sawaya, Michael R.; Furukawa, Hiroyasu; Luo, Fang; Ivanova, Magdalena; Sievers, Stuart A.; Wang, Wenyuan; Yaghi, Omar M.; Liu, Cong; et al

    2014-12-04

    We report that amyloid fibers, once exclusively associated with disease, are acquiring utility as a class of biological nanomaterials. We introduce a method that utilizes the atomic structures of amyloid peptides, to design materials with versatile applications. As a model application, we designed amyloid fibers capable of capturing carbon dioxide from flue gas, to address the global problem of excess anthropogenic carbon dioxide. By measuring dynamic separation of carbon dioxide from nitrogen, we show that fibers with designed amino acid sequences double the carbon dioxide binding capacity of the previously reported fiber formed by VQIVYK from Tau protein. In amore » second application, we designed fibers that facilitate retroviral gene transfer. Finally, by measuring lentiviral transduction, we show that designed fibers exceed the efficiency of polybrene, a commonly used enhancer of transduction. The same procedures can be adapted to the design of countless other amyloid materials with a variety of properties and uses.« less

  5. Structure-Based Design of Functional Amyloid Materials

    SciTech Connect (OSTI)

    Li, Dan; Jones, Eric M.; Sawaya, Michael R.; Furukawa, Hiroyasu; Luo, Fang; Ivanova, Magdalena; Sievers, Stuart A.; Wang, Wenyuan; Yaghi, Omar M.; Liu, Cong; Eisenberg, David S.

    2014-12-04

    We report that amyloid fibers, once exclusively associated with disease, are acquiring utility as a class of biological nanomaterials. We introduce a method that utilizes the atomic structures of amyloid peptides, to design materials with versatile applications. As a model application, we designed amyloid fibers capable of capturing carbon dioxide from flue gas, to address the global problem of excess anthropogenic carbon dioxide. By measuring dynamic separation of carbon dioxide from nitrogen, we show that fibers with designed amino acid sequences double the carbon dioxide binding capacity of the previously reported fiber formed by VQIVYK from Tau protein. In a second application, we designed fibers that facilitate retroviral gene transfer. Finally, by measuring lentiviral transduction, we show that designed fibers exceed the efficiency of polybrene, a commonly used enhancer of transduction. The same procedures can be adapted to the design of countless other amyloid materials with a variety of properties and uses.

  6. Improved structural systems for earth sheltered housing. Structural supplement to the design program

    SciTech Connect (OSTI)

    Behr, R.

    1981-10-01

    Additional engineering information is provided with regard to the structural analysis and design of thin shell concrete structures. The design program has tentatively demonstrated the overall architectural and marketing feasibility of curved, thin shell structural systems for earth sheltered housing. This supplement will address the structural feasibility question by presenting a complete manual analysis and structural design of an earth sheltered dome/tension ring/wall structural system, and also by presenting the results of a parametric sensitivity study of the dome/ring/wall configuration with respect to variations in span and rise for a three foot soil loading condition. Double curvature dome configurations are emphasized in this structural supplement because their analysis is not extensively addressed in earth sheltered housing literature.

  7. Towards Breakthroughs in Protein Structure Calculation and Design | Argonne

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

    Leadership Computing Facility Researchers determined this large protein, ALG13, which is 200 amino acids in length, with a new methodology called "NMR structure determination without side-chain assignments." Towards Breakthroughs in Protein Structure Calculation and Design PI Name: David Baker PI Email: dabaker@u.washington.edu Institution: University of Washington Allocation Program: INCITE Allocation Hours at ALCF: 50 Million Year: 2010 Research Domain: Biological Sciences

  8. Giant structures called plasmoids could simplify the design of future

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

    tokamaks | Princeton Plasma Physics Lab Giant structures called plasmoids could simplify the design of future tokamaks By Raphael Rosen June 2, 2015 Tweet Widget Google Plus One Share on Facebook Left: Plasmoid formation in simulation of NSTX plasma during CHI / Right: Fast-camera image of NSTX plasma shows two discrete plasmoid-like bubble structures. (Photo by Left: Fatima Ebrahimi, PPPL / Right: Nishino-san, Hiroshima University) Left: Plasmoid formation in simulation of NSTX plasma

  9. Giant structures called plasmoids could simplify the design of future

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

    tokamaks | Princeton Plasma Physics Lab Giant structures called plasmoids could simplify the design of future tokamaks By Raphael Rosen June 2, 2015 Tweet Widget Google Plus One Share on Facebook Left: Plasmoid formation in simulation of NSTX plasma during CHI / Right: Fast-camera image of NSTX plasma shows two discrete plasmoid-like bubble structures. (Photo by Left: Credit Fatima Ebrahimi, PPPL / Right: Credit Nishino-san, Hiroshima University) Left: Plasmoid formation in simulation of

  10. Structural Design Feasibility Study for the Global Climate Experiment

    SciTech Connect (OSTI)

    Lewin,K.F.; Nagy, J.

    2008-12-01

    Neon, Inc. is proposing to establish a Global Change Experiment (GCE) Facility to increase our understanding of how ecological systems differ in their vulnerability to changes in climate and other relevant global change drivers, as well as provide the mechanistic basis for forecasting ecological change in the future. The experimental design was initially envisioned to consist of two complementary components; (A) a multi-factor experiment manipulating CO{sub 2}, temperature and water availability and (B) a water balance experiment. As the design analysis and cost estimates progressed, it became clear that (1) the technical difficulties of obtaining tight temperature control and maintaining elevated atmospheric carbon dioxide levels within an enclosure were greater than had been expected and (2) the envisioned study would not fit into the expected budget envelope if this was done in a partially or completely enclosed structure. After discussions between NEON management, the GCE science team, and Keith Lewin, NEON, Inc. requested Keith Lewin to expand the scope of this design study to include open-field exposure systems. In order to develop the GCE design to the point where it can be presented within a proposal for funding, a feasibility study of climate manipulation structures must be conducted to determine design approaches and rough cost estimates, and to identify advantages and disadvantages of these approaches including the associated experimental artifacts. NEON, Inc requested this design study in order to develop concepts for the climate manipulation structures to support the NEON Global Climate Experiment. This study summarizes the design concepts considered for constructing and operating the GCE Facility and their associated construction, maintenance and operations costs. Comparisons and comments about experimental artifacts, construction challenges and operational uncertainties are provided to assist in selecting the final facility design. The overall goal

  11. Design-Load Basis for LANL Structures, Systems, and Components

    SciTech Connect (OSTI)

    I. Cuesta

    2004-09-01

    This document supports the recommendations in the Los Alamos National Laboratory (LANL) Engineering Standard Manual (ESM), Chapter 5--Structural providing the basis for the loads, analysis procedures, and codes to be used in the ESM. It also provides the justification for eliminating the loads to be considered in design, and evidence that the design basis loads are appropriate and consistent with the graded approach required by the Department of Energy (DOE) Code of Federal Regulation Nuclear Safety Management, 10, Part 830. This document focuses on (1) the primary and secondary natural phenomena hazards listed in DOE-G-420.1-2, Appendix C, (2) additional loads not related to natural phenomena hazards, and (3) the design loads on structures during construction.

  12. Design and Structural Analysis of Mars Rover RTG

    SciTech Connect (OSTI)

    Schock, Alfred; Hamrick, T.; Sankarankandath, V.; Shirbacheh, M.

    1989-09-29

    The paper describes the design and the structural and mass analysis of a Radioisotope Thermoelectric Generators (RTGs) for powering the MARS Rover vehicle, which is a critical element of the unmanned Mars Rover and Sample Return mission (MRSR). The RTG design study was conducted by Fairchild Space Company for the U.S. Department of Energy, in support of the Jet Propulsion Laboratory's MRSR project.; The paper briefly describes a reference mission scenario, an illustrative Rover design and activity pattern on Mars, and its power system requirements and environmental constraints, including the RTG cooling requirements during transit to Mars. It identifies the key RTG design problem, i.e. venting the helium generated by the fuel's alpha decay without intrusion of the Martian atmosphere into the RTG, and proposes a design approach for solving that problem.; Using that approach, it describes a very conservative baseline RTG design. The design is based on the proven and safety-qualified General Purpose Heat Source module, and employs standard thermoelectric unicouples whose reliability and performance stability has been extensively demonstrated on previous space missions. The heat source of the 250-watt RTG consists of a stack of 18 separate modules that is supported at its ends but not along its length. The paper describes and analyzes the structure that holds the stack together during Earth launch and Mars operations but allows it to come apart in case of an inadvertent reentry.; A companion paper presented at this conference describes the RTG's thermal and electrical analysis, and compares its performance with that of several lighter but less conservative design options.; There is a duplicate copy in the ESD files. This document is not relevent to OSTI Library. Do not send.

  13. Designing a TAC thermometer from a VHTR graphite structure

    SciTech Connect (OSTI)

    Smith, James A. Kotter, Dale; Garrett, Steven L.; Ali, Randall A.

    2015-03-31

    The interior of a nuclear reactor presents a particularly harsh and challenging environment for both sensors and telemetry due to high temperatures and high fluxes of energetic and ionizing particles among the radioactive decay products. Very High Temperature Reactors are pushing the in core temperatures even higher. A unique sensing approach will be discussed to address the necessary high temperature measurements. Thermoacoustic thermometry exploits high temperatures and uses materials that are immune to the effects of ionizing radiation to create a temperature sensor that is self-powered and wireless. In addition, the form-factor for the Thermoacoustic Thermometer (TACT) can be designed to be integrated within common in-pile structures. There are no physical moving parts required for TACT and the sensor is self-powered, as it uses the nuclear fuel for its heat source. TACT data will be presented from a laboratory prototype mimicking the design necessary for a VHTR graphite structure.

  14. Design of Superconducting Parallel Bar Deflecting and Crabbing rf Structures

    SciTech Connect (OSTI)

    Jean Delayen, Haipeng Wang

    2009-05-01

    A new concept for a deflecting and crabbing rf structure based on half-wave resonant lines was introduced recently*. It offers significant advantages to existing designs and, because of it compactness, allows low frequency operation. This concept has been further refined and optimized for superconducting implementation. Results of this optimization and application to a 400 MHz crabbing cavity and a 499 MHz deflecting cavity are presented.

  15. Durability-based design criteria for an automotive structural composite

    SciTech Connect (OSTI)

    Corum, J.M.; Battiste, R.L.; Brinkman, C.R.; Ren, W.; Ruggles, M.B.; Yahr, G.T.

    1998-11-01

    Before composite structures can be widely used in automotive applications, their long-term durability must be assured. The Durability of Lightweight Composite Structures Project at Oak Ridge National Laboratory was established by the US Department of Energy to help provide that assurance. The project is closely coordinated with the Automotive Composites Consortium. The experimentally-based, durability-driven design criteria described in this paper are the result of the initial project thrust. The criteria address a single reference composite, which is an SRIM (Structural Reaction Injection Molded) polyurethane, reinforced with continuous strand, swirl-mat E-glass fibers. The durability issues addressed include the effects of cyclic and sustained loadings, temperature, automotive fluid environments, and low-energy impacts (e.g., tool drops and roadway kickups) on strength, stiffness, and deformation. The criteria provide design analysis guidance, a multiaxial strength criterion, time-independent and time-dependent allowable stresses, rules for cyclic loading, and damage tolerance design guidance. Environmental degradation factors and the degrading effects of prior loadings are included. Efforts are currently underway to validate the criteria by application to a second random-glass-fiber composite. Carbon-fiber composites are also being addressed.

  16. Building-Integrated Photovoltaic Designs for Commercial and Institutional Structures: A Sourcebook for Architects

    SciTech Connect (OSTI)

    2009-01-18

    Sourcebook for architects on building-integrated photovoltaic designs covering commercial and institutional structures.

  17. Topology Exploration with Hierarchical Landscapes (Conference...

    Office of Scientific and Technical Information (OSTI)

    Topology Exploration with Hierarchical Landscapes Citation Details In-Document Search Title: Topology Exploration with Hierarchical Landscapes Authors: Demir, Dogan ; Beketayev, ...

  18. MHTool User's Guide - Software for Manufactured Housing Structural Design

    SciTech Connect (OSTI)

    W. D. Richins

    2005-07-01

    Since the late 1990s, the Department of Energy's Idaho National Laboratory (INL) has worked with the US Department of Housing and Urban Development (HUD), the Manufactured Housing Institute (MHI), the National Institute of Standards and Technology (NIST), the National Science Foundation (NSF), and an industry committee to measure the response of manufactured housing to both artificial and natural wind loads and to develop a computational desktop tool to optimize the structural performance of manufactured housing to HUD Code loads. MHTool is the result of an 8-year intensive testing and verification effort using single and double section homes. MHTool is the first fully integrated structural analysis software package specifically designed for manufactured housing. To use MHTool, industry design engineers will enter information (geometries, materials, connection types, etc.) describing the structure of a manufactured home, creating a base model. Windows, doors, and interior walls can be added to the initial design. Engineers will input the loads required by the HUD Code (wind, snow loads, interior live loads, etc.) and run an embedded finite element solver to find walls or connections where stresses are either excessive or very low. The designer could, for example, substitute a less expensive and easier to install connection in areas with very low stress, then re-run the analysis for verification. If forces and stresses are still within HUD Code requirements, construction costs would be saved without sacrificing quality. Manufacturers can easily change geometries or component properties to optimize designs of various floor plans then submit MHTool input and output in place of calculations for DAPIA review. No change in the regulatory process is anticipated. MHTool, while not yet complete, is now ready for demonstration. The pre-BETA version (Build-16) was displayed at the 2005 National Congress & Expo for Manufactured & Modular Housing. Additional base models and an

  19. Direct hierarchical assembly of nanoparticles

    DOE Patents [OSTI]

    Xu, Ting; Zhao, Yue; Thorkelsson, Kari

    2014-07-22

    The present invention provides hierarchical assemblies of a block copolymer, a bifunctional linking compound and a nanoparticle. The block copolymers form one micro-domain and the nanoparticles another micro-domain.

  20. Demonstrating Structural Adequacy of Nuclear Power Plant Containment Structures for Beyond Design-Basis Pressure Loadings

    SciTech Connect (OSTI)

    Braverman, J.I.; Morante, R.

    2010-07-18

    ABSTRACT Demonstrating the structural integrity of U.S. nuclear power plant (NPP) containment structures, for beyond design-basis internal pressure loadings, is necessary to satisfy Nuclear Regulatory Commission (NRC) requirements and performance goals. This paper discusses methods for demonstrating the structural adequacy of the containment for beyond design-basis pressure loadings. Three distinct evaluations are addressed: (1) estimating the ultimate pressure capacity of the containment structure (10 CFR 50 and US NRC Standard Review Plan, Section 3.8) ; (2) demonstrating the structural adequacy of the containment subjected to pressure loadings associated with combustible gas generation (10 CFR 52 and 10 CFR 50); and (3) demonstrating the containment structural integrity for severe accidents (10 CFR 52 as well as SECY 90-016, SECY 93-087, and related NRC staff requirements memoranda (SRMs)). The paper describes the technical basis for specific aspects of the methods presented. It also presents examples of past issues identified in licensing activities related to these evaluations.

  1. Structure and Design a Finance Program with Loan Loss Reserve Funds

    Broader source: Energy.gov [DOE]

    The process for structuring and designing a finance program with a loan loss reserve (LLR) fund typically includes research and preparing a finance program design document.

  2. Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5 Zeolites

    SciTech Connect (OSTI)

    Ramasamy, Karthikeyan K.; Zhang, He; Sun, Junming; Wang, Yong

    2014-02-22

    This study reports synthesis, characterization, and catalytic activity of the nano-size hierarchical HZSM-5 zeolite with high mesoporosity produced via a solvent evaporation procedure. Further, this study compares hierarchical zeolites with conventional HZSM-5 zeolite with similar Si/Al ratios for the ethanol-to-hydrocarbon conversion process. The catalytic performance of the hierarchical and conventional zeolites was evaluated using a fixed-bed reactor at 360 °C, 300 psig, and a weight hourly space velocity of 7.9 h-1. For the low Si/Al ratio zeolite (~40), the catalytic life-time for the hierarchical HZSM-5 was approximately 2 times greater than the conventional HZSM-5 despite its coking amount deposited 1.6 times higher than conventional HZSM-5. For the high Si/Al ratio zeolite (~140), the catalytic life-time for the hierarchical zeolite was approximately 5 times greater than the conventional zeolite and the amount of coking deposited was 2.1 times higher. Correlation was observed between catalyst life time, porosity, and the crystal size of the zeolite. The nano-size hierarchical HZSM-5 zeolites containing mesoporosity demonstrated improved catalyst life-time compared to the conventional catalyst due to faster removal of products, shorter diffusion path length, and the migration of the coke deposits to the external surface from the pore structure.

  3. Probing topological protection using a designer surface plasmon structure

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

    Gao, Fei; Gao, Zhen; Shi, Xihang; Yang, Zhaoju; Lin, Xiao; Xu, Hongyi; Joannopoulos, John D.; Soljacic, Marin; Chen, Hongsheng; Lu, Ling; et al

    2016-05-20

    Topological photonic states, inspired by robust chiral edge states in topological insulators, have recently been demonstrated in a few photonic systems, including an array of coupled on-chip ring resonators at communication wavelengths. However, the intrinsic difference between electrons and photons determines that the 'topological protection' in time-reversal-invariant photonic systems does not share the same robustness as its counterpart in electronic topological insulators. Here in a designer surface plasmon platform consisting of tunable metallic sub-wavelength structures, we construct photonic topological edge states and probe their robustness against a variety of defect classes, including some common time-reversal-invariant photonic defects that can breakmore » the topological protection, but do not exist in electronic topological insulators. Furthermore, this is also an experimental realization of anomalous Floquet topological edge states, whose topological phase cannot be predicted by the usual Chern number topological invariants.« less

  4. Software design implementation document for TRAC-M data structures

    SciTech Connect (OSTI)

    Jolly-Woodruff, S. [Ogden Environmental and Energy Services (United States); Mahaffy, J. [Pennsylvania State Univ., University Park, PA (United States); Giguere, P.; Dearing, J.; Boyack, B. [Los Alamos National Lab., NM (United States)

    1997-07-01

    The Transient Reactor Analysis Code (TRAC)-M system-wide and component data structures are to be reimplemented by using the new features of Fortran 90 (F90). There will be no changes to the conceptual design, data flow, or computational flow with respect to the current TRAC-P, except that readability, maintainability, and extensibility will be improved. However, the task described here is a basic step that does not meet all future needs of the code, especially regarding extensibility. TRAC-M will be fully functional and will produce null computational changes with respect to TRAC-P, Version 5.4.25; computational efficiency will not be degraded significantly. The existing component and functional modularity and possibilities for coarse-grained parallelism will be retained.

  5. Hierarchical Heterogeneity at the CeO x –TiO 2 Interface: Electronic and Geometric Structural Influence on the Photocatalytic Activity of Oxide on Oxide Nanostructures

    SciTech Connect (OSTI)

    Luo, Si; Nguyen-Phan, Thuy-Duong; Johnston-Peck, Aaron C.; Barrio, Laura; Sallis, Shawn; Arena, Dario A.; Kundu, Shankhamala; Xu, Wenqian; Piper, Louis F. J.; Stach, Eric A.; Polyanskiy, Dmitry E.; Fujita, Etsuko; Rodriguez, José A.; Senanayake, Sanjaya D.

    2015-01-13

    Mixed oxide interfaces are critical for delivering active components of demanding catalytic processes such as the photo-catalytic splitting of water. We have studied CeOxTiO₂ catalysts with low ceria loadings of 1 wt%, 3 wt% and 6 wt% that were prepared with wet impregnation methods to favor a strong interaction between CeOx and TiO₂. In these materials the interfaces between CeOx-TiO₂ have been sequentially loaded (1%, 3% and 6%), with and without Pt (0.5 wt%). The structure and properties of the catalysts were characterized using several X-ray and electron based techniques including XRD, XPS, UPS, NEXAFS, UV-Vis and HR-STEM/STEM-EELS, to unravel the local morphology, bulk structure, surface states and electronic structure. The combination of all these techniques allow us to analyze in a systematic way the complete structural and electronic properties that prevail at the CeOx-TiO₂ interface. Fluorite structured nano crystallites of ceria on anatase-structured titania were identified by both XRD and NEXAFS. A sequential increasing of the CeOx loading led to the formation of clusters, then plates and finally nano particles in a hierarchical manner on the TiO₂ support. The electronic structures of these catalysts indicate that the interaction between TiO₂ and CeO₂ is closely related to the local morphology of nanostructured CeO₂. Ce³⁺ cations were detected at the surface of CeO₂ and at the interface of the two oxides. In addition, the titania is perturbed by the interaction with ceria and also with Pt. The photocatalytic activity for the splitting of H₂O using UV light was measured for these materials and correlated with our understanding of the electronic and structural properties. Optimal catalytic performance and photo response results were found for the 1 wt% CeOx-TiO₂ catalyst where low dimensional geometry of the ceria provided ideal electronic and geometrical properties

  6. Hierarchical Heterogeneity at the CeO x TiO 2 Interface: Electronic and Geometric Structural Influence on the Photocatalytic Activity of Oxide on Oxide Nanostructures

    SciTech Connect (OSTI)

    Luo, Si; Nguyen-Phan, Thuy-Duong; Johnston-Peck, Aaron C.; Barrio, Laura; Sallis, Shawn; Arena, Dario A.; Kundu, Shankhamala; Xu, Wenqian; Piper, Louis F. J.; Stach, Eric A.; Polyanskiy, Dmitry E.; Fujita, Etsuko; Rodriguez, Jos A.; Senanayake, Sanjaya D.

    2015-01-13

    Mixed oxide interfaces are critical for delivering active components of demanding catalytic processes such as the photo-catalytic splitting of water. We have studied CeOxTiO? catalysts with low ceria loadings of 1 wt%, 3 wt% and 6 wt% that were prepared with wet impregnation methods to favor a strong interaction between CeOx and TiO?. In these materials the interfaces between CeOx-TiO? have been sequentially loaded (1%, 3% and 6%), with and without Pt (0.5 wt%). The structure and properties of the catalysts were characterized using several X-ray and electron based techniques including XRD, XPS, UPS, NEXAFS, UV-Vis and HR-STEM/STEM-EELS, to unravel the local morphology, bulk structure, surface states and electronic structure. The combination of all these techniques allow us to analyze in a systematic way the complete structural and electronic properties that prevail at the CeOx-TiO? interface. Fluorite structured nano crystallites of ceria on anatase-structured titania were identified by both XRD and NEXAFS. A sequential increasing of the CeOx loading led to the formation of clusters, then plates and finally nano particles in a hierarchical manner on the TiO? support. The electronic structures of these catalysts indicate that the interaction between TiO? and CeO? is closely related to the local morphology of nanostructured CeO?. Ce? cations were detected at the surface of CeO? and at the interface of the two oxides. In addition, the titania is perturbed by the interaction with ceria and also with Pt. The photocatalytic activity for the splitting of H?O using UV light was measured for these materials and correlated with our understanding of the electronic and structural properties. Optimal catalytic performance and photo response results were found for the 1 wt% CeOx-TiO? catalyst where low dimensional geometry of the ceria provided ideal electronic and geometrical properties. The structural and

  7. Anti-hierarchical evolution of the active galactic nucleus space density in a hierarchical universe

    SciTech Connect (OSTI)

    Enoki, Motohiro; Ishiyama, Tomoaki; Kobayashi, Masakazu A. R.; Nagashima, Masahiro

    2014-10-10

    Recent observations show that the space density of luminous active galactic nuclei (AGNs) peaks at higher redshifts than that of faint AGNs. This downsizing trend in the AGN evolution seems to be contradictory to the hierarchical structure formation scenario. In this study, we present the AGN space density evolution predicted by a semi-analytic model of galaxy and AGN formation based on the hierarchical structure formation scenario. We demonstrate that our model can reproduce the downsizing trend of the AGN space density evolution. The reason for the downsizing trend in our model is a combination of the cold gas depletion as a consequence of star formation, the gas cooling suppression in massive halos, and the AGN lifetime scaling with the dynamical timescale. We assume that a major merger of galaxies causes a starburst, spheroid formation, and cold gas accretion onto a supermassive black hole (SMBH). We also assume that this cold gas accretion triggers AGN activity. Since the cold gas is mainly depleted by star formation and gas cooling is suppressed in massive dark halos, the amount of cold gas accreted onto SMBHs decreases with cosmic time. Moreover, AGN lifetime increases with cosmic time. Thus, at low redshifts, major mergers do not always lead to luminous AGNs. Because the luminosity of AGNs is correlated with the mass of accreted gas onto SMBHs, the space density of luminous AGNs decreases more quickly than that of faint AGNs. We conclude that the anti-hierarchical evolution of the AGN space density is not contradictory to the hierarchical structure formation scenario.

  8. A Bayesian experimental design approach to structural health monitoring

    SciTech Connect (OSTI)

    Farrar, Charles [Los Alamos National Laboratory; Flynn, Eric [UCSD; Todd, Michael [UCSD

    2010-01-01

    Optimal system design for SHM involves two primarily challenges. The first is the derivation of a proper performance function for a given system design. The second is the development of an efficient optimization algorithm for choosing a design that maximizes, or nearly maximizes the performance function. In this paper we will outline how an SHM practitioner can construct the proper performance function by casting the entire design problem into a framework of Bayesian experimental design. The approach demonstrates how the design problem necessarily ties together all steps of the SHM process.

  9. Towards Breakthroughs in Protein Structure Calculation and Design | Argonne

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

    Leadership Computing Facility A metal-binding protein designed by the Baker laboratory. A metal-binding protein designed by the Baker laboratory, which uses a noncanonical amino acid, bipyradynl alanine, to coordinate the bound metal. Bound metals often play essential catalytic roles at enzyme active sites. Advances made in the current INCITE application will improve the ability to design with non-natural building blocks, and to add enzymatic or other functions to designed proteins. Vikram

  10. Understanding Thin Film Structure for the Rational Design of...

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

    transistors (OTFT) can be achieved through molecular design by selective placement of electron-rich, electron-withdrawing, and aromatic groups in different parts of the molecule. ...

  11. Metal segregation in hierarchically structured cathode materials...

    Office of Scientific and Technical Information (OSTI)

    due to the tailored surface chemistry, compared to conventional NMC-442 materials. ... Nanomaterials; batteries; materials chemistry; surface chemistry Word Cloud More Like ...

  12. Design of Spintronic Materials with Simple Structures (Journal...

    Office of Scientific and Technical Information (OSTI)

    with Simple Structures Citation Details In-Document ... Report Number(s): UCRL-JRNL-230759 TRN: US0807514 DOE Contract Number: W-7405-ENG-48 Resource Type: Journal Article ...

  13. Risk Informed Design and Analysis Criteria for Nuclear Structures

    SciTech Connect (OSTI)

    Salmon, Michael W.

    2015-06-17

    Target performance can be achieved by defining design basis ground motion from results of a probabilistic seismic hazards assessment, and introducing known levels of conservatism in the design above the DBE. ASCE 4, 43, DOE-STD-1020 defined the DBE at 4x10-4 and introduce only slight levels of conservatism in response. ASCE 4, 43, DOE-STD-1020 assume code capacities shoot for about 98% NEP. There is a need to have a uniform target (98% NEP) for code developers (ACI, AISC, etc.) to aim for. In considering strengthening options, one must also consider cost/risk reduction achieved.

  14. Shock-driven fluid-structure interaction for civil design

    SciTech Connect (OSTI)

    Wood, Stephen L; Deiterding, Ralf

    2011-11-01

    The multiphysics fluid-structure interaction simulation of shock-loaded structures requires the dynamic coupling of a shock-capturing flow solver to a solid mechanics solver for large deformations. The Virtual Test Facility combines a Cartesian embedded boundary approach with dynamic mesh adaptation in a generic software framework of flow solvers using hydrodynamic finite volume upwind schemes that are coupled to various explicit finite element solid dynamics solvers (Deiterding et al., 2006). This paper gives a brief overview of the computational approach and presents first simulations that utilize the general purpose solid dynamics code DYNA3D for complex 3D structures of interest in civil engineering. Results from simulations of a reinforced column, highway bridge, multistory building, and nuclear reactor building are presented.

  15. Lattice-structures and constructs with designed thermal expansion coefficients

    DOE Patents [OSTI]

    Spadaccini, Christopher; Hopkins, Jonathan

    2014-10-28

    A thermal expansion-managed lattice structure having a plurality of unit cells each having flexure bearing-mounted tabs supported on a base and actuated by thermal expansion of an actuator having a thermal expansion coefficient greater than the base and arranged so that the tab is inwardly displaced into a base cavity. The flexure bearing-mounted tabs are connected to other flexure-bearing-mounted tabs of adjacent unit cells so that the adjacent unit cells are spaced from each other to accommodate thermal expansion of individual unit cells while maintaining a desired bulk thermal expansion coefficient of the lattice structure as a whole.

  16. Center for Inverse Design: Modality 1 - Inverse Band Structure

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

    1: Inverse Band Structure Modality 1 applies to cases where we have a single material system, but an astronomical number of configurations, and where the target properties can be calculated on the fly. The approach is also called Inverse Band Structure (IBS). The IBS approach began a dozen years ago within the Solid-State Theory group at the National Renewable Energy Laboratory (NREL), under support from the U.S. Department of Energy's Office of Basic Energy Sciences. Imagine that you have a

  17. Procedure for developing biological input for the design, location, or modification of water-intake structures

    SciTech Connect (OSTI)

    Neitzel, D.A.; McKenzie, D.H.

    1981-12-01

    To minimize adverse impact on aquatic ecosystems resulting from the operation of water intake structures, design engineers must have relevant information on the behavior, physiology and ecology of local fish and shellfish. Identification of stimulus/response relationships and the environmental factors that influence them is the first step in incorporating biological information in the design, location or modification of water intake structures. A procedure is presented in this document for providing biological input to engineers who are designing, locating or modifying a water intake structure. The authors discuss sources of stimuli at water intakes, historical approaches in assessing potential/actual impact and review biological information needed for intake design.

  18. Dynamic Non-Hierarchical File Systems for Exascale Storage

    SciTech Connect (OSTI)

    Long, Darrell E.; Miller, Ethan L

    2015-02-24

    This constitutes the final report for “Dynamic Non-Hierarchical File Systems for Exascale Storage”. The ultimate goal of this project was to improve data management in scientific computing and high-end computing (HEC) applications, and to achieve this goal we proposed: to develop the first, HEC-targeted, file system featuring rich metadata and provenance collection, extreme scalability, and future storage hardware integration as core design goals, and to evaluate and develop a flexible non-hierarchical file system interface suitable for providing more powerful and intuitive data management interfaces to HEC and scientific computing users. Data management is swiftly becoming a serious problem in the scientific community – while copious amounts of data are good for obtaining results, finding the right data is often daunting and sometimes impossible. Scientists participating in a Department of Energy workshop noted that most of their time was spent “...finding, processing, organizing, and moving data and it’s going to get much worse”. Scientists should not be forced to become data mining experts in order to retrieve the data they want, nor should they be expected to remember the naming convention they used several years ago for a set of experiments they now wish to revisit. Ideally, locating the data you need would be as easy as browsing the web. Unfortunately, existing data management approaches are usually based on hierarchical naming, a 40 year-old technology designed to manage thousands of files, not exabytes of data. Today’s systems do not take advantage of the rich array of metadata that current high-end computing (HEC) file systems can gather, including content-based metadata and provenance1 information. As a result, current metadata search approaches are typically ad hoc and often work by providing a parallel management system to the “main” file system, as is done in Linux (the locate utility), personal computers, and enterprise search

  19. The structural design of air and gas ducts for power stations and industrial boiler applications

    SciTech Connect (OSTI)

    Schneider, R.L.

    1996-10-01

    The purpose of this paper is to discuss the new American Society of Civil Engineers (ASCE) book entitled, The Structural Design of Air and Gas Ducts for Power Stations and Industrial Boiler Applications. This 312 page book was published by the ASCE in August of 1995. This ASCE publication was created to assist structural engineers in performing the structural analysis and design of air and flue-gas ducts. The structural behavior of steel ductwork can be difficult to understand for structural engineers inexperienced in ductwork analysis and design. Because of this needed expertise, the ASCE committee that created this document highly recommends that the structural analysis and design of ducts be performed by qualified structural engineers, not be technicians, designers or drafters. There is a history within the power industry of failures and major degradation of flue-gas ductwork. There are many reasons for these failures or degradation, but in many cases, the problems may have been voided by a better initial design. This book attempts to help the structural engineer with this task. This book is not intended to be used to size or configure ductwork for flow and pressure drop considerations. But it does recommend that the ductwork system arrangement consider the structural supports and the structural behavior of the duct system.

  20. Thermoelectric Materials by Design, Computational Theory and Structure |

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

    Department of Energy 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. pm_11_singh.pdf (2.16 MB) More Documents & Publications Thermoelectrics Theory and Structure Vehicle Technologies Office: 2008 Oak Ridge Transportation Technology Program Annual Report

  1. Guide to FEMP-Designated Parking Structure Lighting | Department of Energy

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

    Structure Lighting Guide to FEMP-Designated Parking Structure Lighting Document provides acquisition guidance and federal efficiency requirements across a variety of product cate-gories, including parking garage luminaires, which are a FEMP-designated product category. Federal laws and executive orders mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law. Download the guide to FEMP-designated parking

  2. Towards Breakthroughs in Protein Structure Calculation and Design | Argonne

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

    Leadership Computing Facility Hemagglutinin (orange) is an influenza surface protein responsible for viral invasion and infection of cells Hemagglutinin (orange) is an influenza surface protein responsible for viral invasion and infection of cells. Researchers in the Baker lab at the University of Washington have computationally designed a novel protein (blue) that binds to the base of hemagglutinin and effectively neutralizes the flu virus. Credit: Dr. Vikram K. Mulligan, University of

  3. Structure and design of the electron lens for RHIC

    SciTech Connect (OSTI)

    Pikin, A.; Fischer, W.; Alessi, J.; Anerella, M.; Beebe, E. Gassner, D.; Gu, X.; Gupta, R.; Hock, J.; Jain, A.; Lambiase, R.; Luo, Y.; Montag, C.; Okamura, M.; Tan, Y.; Tuozzolo, J.; Thieberger, P.; Zhang, W.

    2011-03-28

    Two electron lenses for a head-on beam-beam compensation are being planned for RHIC; one for each circulating proton beam. The transverse profile of the electron beam will be Gaussian up to a maximum radius of r{sub e} = 3{sigma}. Simulations and design of the electron gun with Gaussian radial emission current density profile and of the electron collector are presented. Ions of the residual gas generated in the interaction region by electron and proton beams will be removed by an axial gradient of the electric field towards the electron collector. A method for the optical observation of the transverse profile of the electron beam is described.

  4. Design, construction, and use of a coiled tubing drilling structure for onshore and offshore operations

    SciTech Connect (OSTI)

    Frishmuth, R.E.; Pursell, J.C.; Middleton, R.J.; Parker, C.O.

    1996-12-31

    This paper discusses the design, construction, and initial application of a structure for supporting a coiled tubing injector head, bottom hole drilling assembly and pressurized lubricator. The paper includes a discussion of the features desired for the structure and how these were addressed during the design. The manufacturing of the support tower and its support platform are then discussed. On site assembly procedures for the movable structure are presented along with photographs of the deployed rig in service. The versatility and usefulness of the structure are discussed from the end users point of view.

  5. Hierarchical analysis of molecular spectra

    SciTech Connect (OSTI)

    Davis, M.J.

    1996-03-01

    A novel representation of molecular spectra in terms of hierarchical trees has proven to be an important aid for the study of many significant problems in gas-phase chemical dynamics. Trees are generated from molecular spectra by monitoring the changes that occur in a spectrum as resolution is changed in a continuous manner. A tree defines a genealogy among all lines of a spectrum. This allows for a detailed understanding of the assignment of features of a spectrum that may be difficult to obtain any other way as well as an understanding of intramolecular energy transfer time scales, mechanisms, and pathways. The methodology has been applied to several problems: transition state spectroscopy, intramolecular energy transfer in highly excited molecules, high-resolution overtone spectroscopy, and the nature of the classical-quantum correspondence when there is classical chaos (``quantum chaos``).

  6. Impact of structural design criteria on first wall surface heat flux limit

    SciTech Connect (OSTI)

    Majumdar, S.

    1998-09-01

    The irradiation environment experienced by the in-vessel components of fusion reactors presents structural design challenges not envisioned in the development of existing structural design criteria such as the ASME Code or RCC-MR. From the standpoint of design criteria, the most significant issues stem from the irradiation-induced changes in material properties, specifically the reduction of ductility, strain hardening capability, and fracture toughness with neutron irradiation. Recently, Draft 7 of the ITER structural design criteria (ISDC), which provide new rules for guarding against such problems, was released for trial use by the ITER designers. The new rules, which were derived from a simple model based on the concept of elastic follow up factor, provide primary and secondary stress limits as functions of uniform elongation and ductility. The implication of these rules on the allowable surface heat flux on typical first walls made of type 316 stainless steel and vanadium alloys are discussed.

  7. Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5...

    Office of Scientific and Technical Information (OSTI)

    Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5 Zeolites Citation Details In-Document Search Title: Conversion of Ethanol to Hydrocarbons on Hierarchical HZSM-5 ...

  8. Durability-Based Design Criteria for a Chopped-Glass-Fiber Automotive Structural Composite

    SciTech Connect (OSTI)

    Battiste, R.L.; Corum, J.M.; Ren, W.; Ruggles, M.B.

    1999-11-01

    This report provides recommended durability-based design criteria for a chopped-glass-fiber reinforced polymeric composite for automotive structural applications. The criteria closely follow the framework of an earlier criteria document for a continuous-strand-mat (CSM) glass-fiber reference composite. Together these design criteria demonstrate a framework that can be adapted for future random-glass-fiber composites for automotive structural applications.

  9. A prototype functional language implementation for hierarchical-memory architectures

    SciTech Connect (OSTI)

    Wolski, R.; Feo, J.; Cann, D.

    1991-06-05

    The first implementation of Sisal was designed for general shared-memory architectures. Since then, we have optimized the system for vector and coherent-cache multiprocessors. Coherent-cache systems can be thought of as simple, two-level hierarchical memory systems, where the memory hierarchy is managed by the hardware. The compiler and run-time system for such an architecture needs to maintain data locality so that the processor caches are used as much as possible. In this paper, we extend the coherent-cache implementation to include explicit compiler and run-time control for medium-grain and coarse-grain hierarchical-memory architectures. We implemented the extended system on the BBN Butterfly using interleaved shared memory exclusively for the purposes of data sharing and exploiting the per-processor local memories. We give preliminary performance results for this extended system. 10 refs., 7 figs.

  10. Design and fabrication of a traveling-wave muffin-tin accelerating structure at 90 GHz

    SciTech Connect (OSTI)

    Chou, P.J.; Bowden, G.B.; Copeland, M.R.; Menegat, A.; Siemann, R.H.; Henke, H.

    1997-05-01

    A prototype of a muffin-tin accelerating structure operating at 32 times the SLAC frequency (2.856 GHz) was built for research in high gradient acceleration. A traveling-wave design with single input and output feeds was chosen for the prototype which was fabricated by wire electrodischarge machining. Features of the mechanical design for the prototype are described. Design improvements are presented including considerations of cooling and vacuum.

  11. Structural Design of a Horizontal-Axis Tidal Current Turbine Composite Blade

    SciTech Connect (OSTI)

    Bir, G. S.; Lawson, M. J.; Li, Y.

    2011-10-01

    This paper describes the structural design of a tidal composite blade. The structural design is preceded by two steps: hydrodynamic design and determination of extreme loads. The hydrodynamic design provides the chord and twist distributions along the blade length that result in optimal performance of the tidal turbine over its lifetime. The extreme loads, i.e. the extreme flap and edgewise loads that the blade would likely encounter over its lifetime, are associated with extreme tidal flow conditions and are obtained using a computational fluid dynamics (CFD) software. Given the blade external shape and the extreme loads, we use a laminate-theory-based structural design to determine the optimal layout of composite laminas such that the ultimate-strength and buckling-resistance criteria are satisfied at all points in the blade. The structural design approach allows for arbitrary specification of the chord, twist, and airfoil geometry along the blade and an arbitrary number of shear webs. In addition, certain fabrication criteria are imposed, for example, each composite laminate must be an integral multiple of its constituent ply thickness. In the present effort, the structural design uses only static extreme loads; dynamic-loads-based fatigue design will be addressed in the future. Following the blade design, we compute the distributed structural properties, i.e. flap stiffness, edgewise stiffness, torsion stiffness, mass, moments of inertia, elastic-axis offset, and center-of-mass offset along the blade. Such properties are required by hydro-elastic codes to model the tidal current turbine and to perform modal, stability, loads, and response analyses.

  12. A Scrutiny of the Equivalent Static Lateral Load Method of Design for Multistory Masonry Structures

    SciTech Connect (OSTI)

    Touqan, A. R.; Helou, S. H.

    2008-07-08

    Building structures with a soft storey are gaining widespread popularity in urban areas due to the scarcity of land and due to the pressing need for wide open spaces at the entrance level. In earthquake prone zones dynamic analysis based on the Equivalent Static Lateral Load method is attractive to the novice and the design codes leave the choice of the analysis procedure up to the discretion of the designer. The following is a comparison of the said method with the more elaborate Response Spectrum Method of analysis as they apply to a repertoire of different structural models. The results clearly show that the former provides similar results of response in structures with gradual change in storey stiffness; while it is over conservative for a bare frame structure. It is however less conservative for structures with a soft storey.

  13. Extragalactic Background Light from Hierarchical Galaxy Formation:

    Office of Scientific and Technical Information (OSTI)

    Gamma-ray Attenuation up to the Epoch of Cosmic Reionization and the First Stars (Journal Article) | SciTech Connect Journal Article: Extragalactic Background Light from Hierarchical Galaxy Formation: Gamma-ray Attenuation up to the Epoch of Cosmic Reionization and the First Stars Citation Details In-Document Search Title: Extragalactic Background Light from Hierarchical Galaxy Formation: Gamma-ray Attenuation up to the Epoch of Cosmic Reionization and the First Stars Authors: Inoue,

  14. Unveiling Surface Redox Charge Storage of Interacting Two-Dimensional Hetero-Nanosheets in Hierarchical Architectures

    SciTech Connect (OSTI)

    Mahmood, Qasim; Bak, Seong-Min; Kim, Min G.; Yun, Sol; Yang, Xiao-Qing; Shin, Hyeon S.; Kim, Woo S.; Braun, Paul V.; Park, Ho S.

    2015-03-03

    Two-dimensional (2D) heteronanosheets are currently the focus of intense study due to the unique properties that emerge from the interplay between two low-dimensional nanomaterials with different properties. However, the properties and new phenomena based on the two 2D heteronanosheets interacting in a 3D hierarchical architecture have yet to be explored. Here, we unveil the surface redox charge storage mechanism of surface-exposed WS2 nanosheets assembled in a 3D hierarchical heterostructure using in situ synchrotron X-ray absorption and Raman spectroscopic methods. The surface dominating redox charge storage of WS2 is manifested in a highly reversible and ultrafast capacitive fashion due to the interaction of heteronanosheets and the 3D connectivity of the hierarchical structure. In contrast, compositionally identical 2D WS2 structures fail to provide a fast and high capacitance with different modes of lattice vibration. The distinctive surface capacitive behavior of 3D hierarchically structured heteronanosheets is associated with rapid proton accommodation into the in-plane WS lattice (with the softening of the E2g bands), the reversible redox transition of the surface-exposed intralayers residing in the electrochemically active 1T phase of WS2 (with the reversible change in the interatomic distance and peak intensity of WW bonds), and the change in the oxidation state during the proton insertion/deinsertion process. This proposed mechanism agrees with the dramatic improvement in the capacitive performance of the two heteronanosheets coupled in the hierarchical structure.

  15. Unveiling Surface Redox Charge Storage of Interacting Two-Dimensional Hetero-Nanosheets in Hierarchical Architectures

    SciTech Connect (OSTI)

    Mahmood, Qasim; Bak, Seong-Min; Kim, Min G.; Yun, Sol; Yang, Xiao-Qing; Shin, Hyeon S.; Kim, Woo S.; Braun, Paul V.; Park, Ho S.

    2015-03-03

    Two-dimensional (2D) heteronanosheets are currently the focus of intense study due to the unique properties that emerge from the interplay between two low-dimensional nanomaterials with different properties. However, the properties and new phenomena based on the two 2D heteronanosheets interacting in a 3D hierarchical architecture have yet to be explored. Here, we unveil the surface redox charge storage mechanism of surface-exposed WS2 nanosheets assembled in a 3D hierarchical heterostructure using in situ synchrotron X-ray absorption and Raman spectroscopic methods. The surface dominating redox charge storage of WS2 is manifested in a highly reversible and ultrafast capacitive fashion due to the interaction of heteronanosheets and the 3D connectivity of the hierarchical structure. In contrast, compositionally identical 2D WS2 structures fail to provide a fast and high capacitance with different modes of lattice vibration. The distinctive surface capacitive behavior of 3D hierarchically structured heteronanosheets is associated with rapid proton accommodation into the in-plane W–S lattice (with the softening of the E2g bands), the reversible redox transition of the surface-exposed intralayers residing in the electrochemically active 1T phase of WS2 (with the reversible change in the interatomic distance and peak intensity of W–W bonds), and the change in the oxidation state during the proton insertion/deinsertion process. This proposed mechanism agrees with the dramatic improvement in the capacitive performance of the two heteronanosheets coupled in the hierarchical structure.

  16. Design structure for in-system redundant array repair in integrated circuits

    DOE Patents [OSTI]

    Bright, Arthur A.; Crumley, Paul G.; Dombrowa, Marc; Douskey, Steven M.; Haring, Rudolf A.; Oakland, Steven F.; Quellette, Michael R.; Strissel, Scott A.

    2008-11-25

    A design structure for repairing an integrated circuit during operation of the integrated circuit. The integrated circuit comprising of a multitude of memory arrays and a fuse box holding control data for controlling redundancy logic of the arrays. The design structure provides the integrated circuit with a control data selector for passing the control data from the fuse box to the memory arrays; providing a source of alternate control data, external of the integrated circuit; and connecting the source of alternate control data to the control data selector. The design structure further passes the alternate control data from the source thereof, through the control data selector and to the memory arrays to control the redundancy logic of the memory arrays.

  17. Preliminary structural design conceptualization for composite rotor for verdant power water current turbine

    SciTech Connect (OSTI)

    Paquette, J. A.

    2012-03-01

    Sandia National Laboratories (SNL) and Verdant Power Inc. (VPI) have partnered under a Cooperative Research and Development Agreement (CRADA) to develop a new kinetic hydropower rotor. The rotor features an improved hydrodynamic and structural design which features state-of-the-art technology developed for the wind industry. The new rotor will have higher energy capture, increased system reliability, and reduction of overall cost of energy. This project was divided into six tasks: (1) Composite Rotor Project Planning and Design Specification; (2) Baseline Fatigue Testing and Failure analysis; (3) Develop Blade/Rotor Performance Model; (4) Hydrofoil Survey and Selection; (5) FEM Structural Design; and (6) Develop Candidate Rotor Designs and Prepare Final Report.

  18. Structures of trihydroxynaphthalene reductase-fungicide complexes: implications for structure-based design and catalysis

    SciTech Connect (OSTI)

    Liao, D.-I.; Basarab, G.S.; Gatenby, A.A.; Valent, B.; Jordan, D.B.

    2010-03-08

    Trihydroxynaphthalene reductase catalyzes two intermediate steps in the fungal melanin biosynthetic pathway. The enzyme, a typical short-chain dehydrogenase, is the biochemical target of three commercial fungicides. The fungicides bind preferentially to the NADPH form of the enzyme. Three X-ray structures of the Magnaporthe grisea enzyme complexed with NADPH and two commercial and one experimental fungicide were determined at 1.7 {angstrom} (pyroquilon), 2.0 {angstrom} (2,3-dihydro-4-nitro-1H-inden-1-one, 1), and 2.1 {angstrom} (phthalide) resolutions. The chemically distinct inhibitors occupy similar space within the enzyme's active site. The three inhibitors share hydrogen bonds with the side chain hydroxyls of Ser-164 and Tyr-178 via a carbonyl oxygen (pyroquilon and 1) or via a carbonyl oxygen and a ring oxygen (phthalide). Active site residues occupy similar positions among the three structures. A buried water molecule that is hydrogen bonded to the NZ nitrogen of Lys-182 in each of the three structures likely serves to stabilize the cationic form of the residue for participation in catalysis. The pro S hydrogen of NADPH (which is transferred as a hydride to the enzyme's naphthol substrates) is directed toward the carbonyl carbon of the inhibitors that mimic an intermediate along the reaction coordinate. Modeling tetrahydroxynaphthalene and trihydroxynaphthalene in the active site shows steric and electrostatic repulsion between the extra hydroxyl oxygen of the former substrate and the sulfur atom of Met-283 (the C-terminal residue), which accounts, in part, for the 4-fold greater substrate specificity for trihydroxynaphthalene over tetrahydroxynaphthalene.

  19. An Evaluation of Frangible Materials as Veneers on Vented Structural Member Designs

    SciTech Connect (OSTI)

    Jameson, Kevin Jay

    2015-10-01

    Literature shows there has been extensive research and testing done in the area of wall panels and frangible materials. There is evidence from past research that shows it is possible to vent a structure that has had an accidental internal explosion [1]. The reviewed literature shows that most designs vent the entire wall panel versus a frangible material attached to the wall panel. The frangible material attachment points are important to determine the overall loading of the wall panel structure [2]. The materials used in the reviewed literature were securely attached as well as strong enough to remain intact during the pressure loading to move the entire wall panel. Since the vented wall panel was the weakest part of the overall structure, the other walls of the structure were substantially larger. The structure was usually built from concrete and large amounts of steel with dirt and sand over the top of the structure.The study will be conducted at Sandia National Laboratories located in Albuquerque New Mexico. The skeletal structural design for evaluation is a rectangular frame with a square grid pattern constructed from steel. The skeletal structure has been given to the researcher as a design requirement. The grid pattern will be evaluated strictly on plastic deformation and the loading that is applied from the frangible material. The frangible material tested will either fit into the grid or will be a veneer lightly attached to the structure frame. The frangible material may be required on both sides of the structure to adequately represent the application.

  20. Optimal design at inner core of the shaped pyramidal truss structure

    SciTech Connect (OSTI)

    Lee, Sung-Uk; Yang, Dong-Yol

    2013-12-16

    Sandwich material is a type of composite material with lightweight, high strength, good dynamic properties and high bending stiffness-to-weight ratio. This can be found well such structures in the nature (for example, internal structure of bones, plants, etc.). New trend which prefers eco-friendly products and energy efficiency is emerging in industries recently. Demand for materials with high strength and light weight is also increasing. In line with these trends, researches about manufacturing methods of sandwich material have been actively conducted. In this study, a sandwich structure named as “Shaped Pyramidal Truss Structure” is proposed to improve mechanical strength and to apply a manufacturing process suitable for massive production. The new sandwich structure was designed to enhance compressive strength by changing the cross-sectional shape at the central portion of the core. As the next step, optimization of the shape was required. Optimization technique used here was the SZGA(Successive Zooming Genetic Algorithm), which is one of GA(Genetic Algorithm) methods gradually reducing the area of design variable. The objective function was defined as moment of inertia of the cross-sectional shape of the strut. The control points of cubic Bezier curve, which was assumed to be the shape of the cross section, were used as design variables. By using FEM simulation, it was found that the structure exhibited superior mechanical properties compared to the simple design of the prior art.

  1. Structural performance of the first SSC (Superconducting Super Collider) Design B dipole magnet

    SciTech Connect (OSTI)

    Nicol, T.H.

    1989-09-01

    The first Design B Superconducting Super Collider (SSC) dipole magnet has been successfully tested. This magnet was heavily instrumented with temperature and strain gage sensors in order to evaluate its adherence to design constraints and design calculations. The instrumentation and associated data acquisition system allowed monitoring of the magnet during cooldown, warmup, and quench testing. This paper will focus on the results obtained from structural measurements on the suspension system during normal and rapid cooldowns and during quench studies at full magnet current. 4 refs., 9 figs.

  2. Design of the support structure, drive pedestal, and controls for a solar concentrator

    SciTech Connect (OSTI)

    Goldberg, V.R.; Ford, J.L.; Anderson, A.E. )

    1991-08-01

    The glass/metal McDonnell-Douglas dish is the state-of-the-art of parabolic dish concentrators. Because of the perceived high production cost of this concentrator, the Department of Energy's Solar Thermal Program is developing stretch-membrane technology for large (75 kWt) solar concentrators for integration with receivers and engines in 25 kWe dish-Stirling systems. The objective of this development effort is to reduce the cost of the concentrator while maintaining the high levels of performance characteristic of glass-metal dishes. Under contract to Sandia National Laboratories, Science Applications International Corporation, Solar Kinetics Inc. and WG Associates are developing a faceted stretched-membrane heliostat technology. This design will result in a low-risk, near-term concentrator for dish-Stirling systems. WG Associates has designed the support structure, drives and tracking controls for this dish. The structure is configured to support 12 stretched-membrane, 3.5-meter diameter facets in a shaped dish configuration. The dish design is sized to power a dish-Stirling system capable of producing 25 kW (electric). In the design of the structure, trade-off studies were conducted to determine the best'' facet arrangement, dish contour, dish focal length, tracking control and walk-off protection. As part of the design, in-depth analyses were performed to evaluate pointing accuracy, compliance with AISC steel design codes, and the economics of fabrication and installation. Detailed fabrication and installation drawings were produced, and initial production cost estimates for the dish were developed. These issues, and the final dish design, are presented in this report. 7 refs., 33 figs., 18 tabs.

  3. Structure Based Drug Design for HIM Protease: From Molecular Modeling to Cheminformatics

    SciTech Connect (OSTI)

    Volarath, Patra; Weber, Irene T.; Harrison, Robert W.

    2008-06-06

    Significant progress over the past decade in virtual representations of molecules and their physicochemical properties has produced new drugs from virtual screening of the structures of single protein molecules by conventional modeling methods. The development of clinical antiviral drugs from structural data for HIV protease has been a major success in structure based drug design. Techniques for virtual screening involve the ranking of the affinity of potential ligands for the target site on a protein. Two main alternatives have been developed: modeling of the target protein with a series of related ligand molecules, and docking molecules from a database to the target protein site. The computational speed and prediction accuracy will depend on the representation of the molecular structure and chemistry, the search or simulation algorithm, and the scoring function to rank the ligands. Moreover, the general challenges in modern computational drug design arise from the profusion of data, including whole genomes of DNA, protein structures, chemical libraries, affinity and pharmacological data. Therefore, software tools are being developed to manage and integrate diverse data, and extract and visualize meaningful relationships. Current areas of research include the development of searchable chemical databases, which requires new algorithms to represent molecules and search for structurally or chemically similar molecules, and the incorporation of machine learning techniques for data mining to improve the accuracy of predictions. Examples will be presented for the virtual screening of drugs that target HIV protease.

  4. Evaluation of proposed designs for streamflow monitoring structures at waste disposal sites

    SciTech Connect (OSTI)

    Clapp, R.B.; Borders, D.M.; Tardiff, M.F.; Huff, D.D.

    1991-01-01

    Design of small surface water monitoring stations associated with waste sites requires an approach that balances several problems. The monitoring site must have a capacity for a wide range of flows, allow accurate measurements over the full performance range, minimize effects from accumulation of contaminated sediments, and minimize costs of construction and operation. Selecting a station design that takes these factors into consideration can be done systematically through use of formal decision analysis. The paper discusses the effectiveness of various hydraulic structures as flumes and weirs to monitor stream flow and drainage. The process has produced the most viable alternative designs and yielded fully documented guidelines for designing new stations as they are needed. 7 refs., 6 figs., 3 tabs.

  5. Criteria for design of the Yucca Mountain structures, systems and components for fault displacement

    SciTech Connect (OSTI)

    Stepp, C.; Hossain, Q.; Nesbit, S.; Hardy, M.

    1995-12-31

    The DOE intends to design the Yucca Mountain high-level waste facility structures, systems and components (SSCs) for fault displacements to provide reasonable assurance that they will meet the preclosure safety performance objectives established by 10 CFR Part 60. To the extent achievable, fault displacement design of the facility will follow guidance provided in the NRC Staff Technical Position. Fault avoidance will be the primary design criterion, especially for spatially compact or clustered SSCs. When fault avoidance is not reasonably achievable, expected to be the case for most spatially extended SSCs, engineering design procedures and criteria or repair and rehabilitation actions, depending on the SSC`s importance to safety, are provided. SSCs that have radiological safety importance will be designed for fault displacements that correspond to the hazard exceedance frequency equal to their established seismic safety performance goals. Fault displacement loads are generally localized and may cause local inelastic response of SSCs. For this reason, the DOE intends to use strain-based design acceptance criteria similar to the strain-based criteria used to design nuclear plant SSCs for impact and impulsive loads.

  6. Durability-Based Design Guide for an Automotive Structural Composite: Part 2. Background Data and Models

    SciTech Connect (OSTI)

    Corum, J.M.; Battiste, R.L.; Brinkman, C.R.; Ren, W.; Ruggles, M.B.; Weitsman, Y.J.; Yahr, G.T.

    1998-02-01

    This background report is a companion to the document entitled ''Durability-Based Design Criteria for an Automotive Structural Composite: Part 1. Design Rules'' (ORNL-6930). The rules and the supporting material characterization and modeling efforts described here are the result of a U.S. Department of Energy Advanced Automotive Materials project entitled ''Durability of Lightweight Composite Structures.'' The overall goal of the project is to develop experimentally based, durability-driven design guidelines for automotive structural composites. The project is closely coordinated with the Automotive Composites Consortium (ACC). The initial reference material addressed by the rules and this background report was chosen and supplied by ACC. The material is a structural reaction injection-molded isocyanurate (urethane), reinforced with continuous-strand, swirl-mat, E-glass fibers. This report consists of 16 position papers, each summarizing the observations and results of a key area of investigation carried out to provide the basis for the durability-based design guide. The durability issues addressed include the effects of cyclic and sustained loadings, temperature, automotive fluids, vibrations, and low-energy impacts (e.g., tool drops and roadway kickups) on deformation, strength, and stiffness. The position papers cover these durability issues. Topics include (1) tensile, compressive, shear, and flexural properties; (2) creep and creep rupture; (3) cyclic fatigue; (4) the effects of temperature, environment, and prior loadings; (5) a multiaxial strength criterion; (6) impact damage and damage tolerance design; (7) stress concentrations; (8) a damage-based predictive model for time-dependent deformations; (9) confirmatory subscale component tests; and (10) damage development and growth observations.

  7. Structural Aspects of Hydrogen Bonding with Nitrate and Sulfate: Design Criteria for Polyalcohol Hosts

    SciTech Connect (OSTI)

    Hay, Benjamin P.; Dixon, David A.; Lumetta, Gregg J.; Vargas, Rubicelia; Garza, Jorge

    2004-01-01

    Organic hosts for oxyanion complexation can be constructed by combining two or more hydrogen bonding sites. The deliberate design of architectures for such hosts requires knowledge of the optimal geometry for the hydrogen bonds formed between the host and the guest. Important structural parameters include the O--H distance, the O--H-D angle, the X-O--H angle, and the X-O--H-D dihedral angle (H-D=hydrogen bond donor, X=any atom). This information can be obtained through the analysis of hydrogen bonding observed in crystal structures and electronic structure calculations on simple gas-phase complexes. In this chapter, we present an analysis of hydrogen bonding structural parameters for alcohol hydrogen donors and the oxygen atom acceptors in nitrate and sulfate.

  8. Structure of a designed protein cage that self-assembles into a highly porous cube

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

    Lai, Yen-Ting; Reading, Eamonn; Hura, Greg L.; Tsai, Kuang-Lei; Laganowsky, Arthur; Asturias, Francisco J.; Tainer, John A.; Robinson, Carol V.; Yeates, Todd O.

    2014-11-10

    Natural proteins can be versatile building blocks for multimeric, self-assembling structures. Yet, creating protein-based assemblies with specific geometries and chemical properties remains challenging. Highly porous materials represent particularly interesting targets for designed assembly. Here we utilize a strategy of fusing two natural protein oligomers using a continuous alpha-helical linker to design a novel protein that self assembles into a 750 kDa, 225 Å diameter, cube-shaped cage with large openings into a 130 Å diameter inner cavity. A crystal structure of the cage showed atomic level agreement with the designed model, while electron microscopy, native mass spectrometry, and small angle x-raymore » scattering revealed alternate assembly forms in solution. These studies show that accurate design of large porous assemblies with specific shapes is feasible, while further specificity improvements will likely require limiting flexibility to select against alternative forms. Finally, these results provide a foundation for the design of advanced materials with applications in bionanotechnology, nanomedicine and material sciences.« less

  9. Structural Testing at the NWTC Helps Improve Blade Design and Increase System Reliability; NREL (National Renewable Energy Laboratory)

    SciTech Connect (OSTI)

    2015-08-01

    Since 1990, the National Renewable Energy Laboratory’s (NREL's) National Wind Technology Center (NWTC) has tested more than 150 wind turbine blades. NWTC researchers can test full-scale and subcomponent articles, conduct data analyses, and provide engineering expertise on best design practices. Structural testing of wind turbine blades enables designers, manufacturers, and owners to validate designs and assess structural performance to specific load conditions. Rigorous structural testing can reveal design and manufacturing problems at an early stage of development that can lead to overall improvements in design and increase system reliability.

  10. Hierarchical resilience with lightweight threads.

    SciTech Connect (OSTI)

    Wheeler, Kyle Bruce

    2011-10-01

    This paper proposes methodology for providing robustness and resilience for a highly threaded distributed- and shared-memory environment based on well-defined inputs and outputs to lightweight tasks. These inputs and outputs form a failure 'barrier', allowing tasks to be restarted or duplicated as necessary. These barriers must be expanded based on task behavior, such as communication between tasks, but do not prohibit any given behavior. One of the trends in high-performance computing codes seems to be a trend toward self-contained functions that mimic functional programming. Software designers are trending toward a model of software design where their core functions are specified in side-effect free or low-side-effect ways, wherein the inputs and outputs of the functions are well-defined. This provides the ability to copy the inputs to wherever they need to be - whether that's the other side of the PCI bus or the other side of the network - do work on that input using local memory, and then copy the outputs back (as needed). This design pattern is popular among new distributed threading environment designs. Such designs include the Barcelona STARS system, distributed OpenMP systems, the Habanero-C and Habanero-Java systems from Vivek Sarkar at Rice University, the HPX/ParalleX model from LSU, as well as our own Scalable Parallel Runtime effort (SPR) and the Trilinos stateless kernels. This design pattern is also shared by CUDA and several OpenMP extensions for GPU-type accelerators (e.g. the PGI OpenMP extensions).

  11. Design, Construction and Test of Cryogen-Free HTS Coil Structure

    SciTech Connect (OSTI)

    Hocker, H.; Anerella, M.; Gupta, R.; Plate, S.; Sampson, W.; Schmalzle, J.; Shiroyanagi, Y.

    2011-03-28

    This paper will describe design, construction and test results of a cryo-mechanical structure to study coils made with the second generation High Temperature Superconductor (HTS) for the Facility for Rare Isotope Beams (FRIB). A magnet comprised of HTS coils mounted in a vacuum vessel and conduction-cooled with Gifford-McMahon cycle cryocoolers is used to develop and refine design and construction techniques. The study of these techniques and their effect on operations provides a better understanding of the use of cryogen free magnets in future accelerator projects. A cryogen-free, superconducting HTS magnet possesses certain operational advantages over cryogenically cooled, low temperature superconducting magnets.

  12. Metal oxide nanostructures with hierarchical morphology

    DOE Patents [OSTI]

    Ren, Zhifeng; Lao, Jing Yu; Banerjee, Debasish

    2007-11-13

    The present invention relates generally to metal oxide materials with varied symmetrical nanostructure morphologies. In particular, the present invention provides metal oxide materials comprising one or more metallic oxides with three-dimensionally ordered nanostructural morphologies, including hierarchical morphologies. The present invention also provides methods for producing such metal oxide materials.

  13. Topology Exploration with Hierarchical Landscapes

    Office of Scientific and Technical Information (OSTI)

    ... Proc. o f SIG G RAPH '96, 109-118. MlZUTA, S ., S u w a , Y., O n o , T., AND M a t s u d a , T. 2004. D e - scription o f the topological structure o f digital im ages by contour ...

  14. InGaN-based thin film solar cells: Epitaxy, structural design, and photovoltaic properties

    SciTech Connect (OSTI)

    Sang, Liwen; Liao, Meiyong; Koide, Yasuo; Sumiya, Masatomo

    2015-03-14

    In{sub x}Ga{sub 1−x}N, with the tunable direct bandgaps from ultraviolet to near infrared region, offers a promising candidate for the high-efficiency next-generation thin-film photovoltaic applications. Although the adoption of thick InGaN film as the active region is desirable to obtain efficient light absorption and carrier collection compared to InGaN/GaN quantum wells structure, the understanding on the effect from structural design is still unclear due to the poor-quality InGaN films with thickness and difficulty of p-type doping. In this paper, we comprehensively investigate the effects from film epitaxy, doping, and device structural design on the performances of the InGaN-based solar cells. The high-quality InGaN thick film is obtained on AlN/sapphire template, and p-In{sub 0.08}Ga{sub 0.92}N is achieved with a high hole concentration of more than 10{sup 18 }cm{sup −3}. The dependence of the photovoltaic performances on different structures, such as active regions and p-type regions is analyzed with respect to the carrier transport mechanism in the dark and under illumination. The strategy of improving the p-i interface by using a super-thin AlN interlayer is provided, which successfully enhances the performance of the solar cells.

  15. Structure-Based Design of Novel HIV-1 Protease Inhibitors to Combat Drug Resistance

    SciTech Connect (OSTI)

    Ghosh,A.; Sridhar, P.; Leshchenko, S.; Hussain, A.; Li, J.; Kovalevsky, A.; Walters, D.; Wedelind, J.; Grum-Tokars, V.; et al.

    2006-01-01

    Structure-based design and synthesis of novel HIV protease inhibitors are described. The inhibitors are designed specifically to interact with the backbone of HIV protease active site to combat drug resistance. Inhibitor 3 has exhibited exceedingly potent enzyme inhibitory and antiviral potency. Furthermore, this inhibitor maintains impressive potency against a wide spectrum of HIV including a variety of multi-PI-resistant clinical strains. The inhibitors incorporated a stereochemically defined 5-hexahydrocyclopenta[b]furanyl urethane as the P2-ligand into the (R)-(hydroxyethylamino)sulfonamide isostere. Optically active (3aS,5R,6aR)-5-hydroxy-hexahydrocyclopenta[b]furan was prepared by an enzymatic asymmetrization of meso-diacetate with acetyl cholinesterase, radical cyclization, and Lewis acid-catalyzed anomeric reduction as the key steps. A protein-ligand X-ray crystal structure of inhibitor 3-bound HIV-1 protease (1.35 Angstroms resolution) revealed extensive interactions in the HIV protease active site including strong hydrogen bonding interactions with the backbone. This design strategy may lead to novel inhibitors that can combat drug resistance.

  16. Spatially addressable design of gradient index structures through spatial light modulator based holographic lithography

    SciTech Connect (OSTI)

    Ohlinger, Kris; Lutkenhaus, Jeff [Department of Physics, University of North Texas, Denton, Texas 76203 (United States); Arigong, Bayaner; Zhang, Hualiang [Department of Electrical Engineering, University of North Texas, Denton, Texas 76203 (United States); Lin, Yuankun, E-mail: yuankun.lin@unt.edu [Department of Physics, University of North Texas, Denton, Texas 76203 (United States); Department of Electrical Engineering, University of North Texas, Denton, Texas 76203 (United States)

    2013-12-07

    In this paper, we present an achievable gradient refractive index in bi-continuous holographic structures that are formed through five-beam interference. We further present a theoretic approach for the realization of gradient index devices by engineering the phases of the interfering beams with a pixelated spatial light modulator. As an example, the design concept of a gradient index Luneburg lens is verified through full-wave electromagnetic simulations. These five beams with desired phases can be generated through programming gray level super-cells in a diffractive spatial light modulator. As a proof-of-concept, gradient index structures are demonstrated using synthesized and gradient phase patterns displayed in the spatial light modulator.

  17. Unveiling Surface Redox Charge Storage of Interacting Two-Dimensional Hetero-Nanosheets in Hierarchical Architectures

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

    Mahmood, Qasim; Bak, Seong-Min; Kim, Min G.; Yun, Sol; Yang, Xiao-Qing; Shin, Hyeon S.; Kim, Woo S.; Braun, Paul V.; Park, Ho S.

    2015-03-03

    Two-dimensional (2D) heteronanosheets are currently the focus of intense study due to the unique properties that emerge from the interplay between two low-dimensional nanomaterials with different properties. However, the properties and new phenomena based on the two 2D heteronanosheets interacting in a 3D hierarchical architecture have yet to be explored. Here, we unveil the surface redox charge storage mechanism of surface-exposed WS2 nanosheets assembled in a 3D hierarchical heterostructure using in situ synchrotron X-ray absorption and Raman spectroscopic methods. The surface dominating redox charge storage of WS2 is manifested in a highly reversible and ultrafast capacitive fashion due to themore » interaction of heteronanosheets and the 3D connectivity of the hierarchical structure. In contrast, compositionally identical 2D WS2 structures fail to provide a fast and high capacitance with different modes of lattice vibration. The distinctive surface capacitive behavior of 3D hierarchically structured heteronanosheets is associated with rapid proton accommodation into the in-plane W–S lattice (with the softening of the E2g bands), the reversible redox transition of the surface-exposed intralayers residing in the electrochemically active 1T phase of WS2 (with the reversible change in the interatomic distance and peak intensity of W–W bonds), and the change in the oxidation state during the proton insertion/deinsertion process. This proposed mechanism agrees with the dramatic improvement in the capacitive performance of the two heteronanosheets coupled in the hierarchical structure.« less

  18. STRUCTURAL DESIGN CRITERIA FOR TARGET/BLANKET SYSTEM COMPONENT MATERIALS FOR THE ACCELERATOR PRODUCTION OF TRITIUM PROJECT

    SciTech Connect (OSTI)

    W. JOHNSON; R. RYDER; P. RITTENHOUSE

    2001-01-01

    The design of target/blanket system components for the Accelerator Production of Tritium (APT) plant is dependent on the development of materials properties data specified by the designer. These data are needed to verify that component designs are adequate. The adequacy of the data will be related to safety, performance, and economic considerations, and to other requirements that may be deemed necessary by customers and regulatory bodies. The data required may already be in existence, as in the open technical literature, or may need to be generated, as is often the case for the design of new systems operating under relatively unique conditions. The designers' starting point for design data needs is generally some form of design criteria used in conjunction with a specified set of loading conditions and associated performance requirements. Most criteria are aimed at verifying the structural adequacy of the component, and often take the form of national or international standards such as the ASME Boiler and Pressure Vessel Code (ASME B and PV Code) or the French Nuclear Structural Requirements (RCC-MR). Whether or not there are specific design data needs associated with the use of these design criteria will largely depend on the uniqueness of the conditions of operation of the component. A component designed in accordance with the ASME B and PV Code, where no unusual environmental conditions exist, will utilize well-documented, statistically-evaluated developed in conjunction with the Code, and will not be likely to have any design data needs. On the other hand, a component to be designed to operate under unique APT conditions, is likely to have significant design data needs. Such a component is also likely to require special design criteria for verification of its structural adequacy, specifically accounting for changes in materials properties which may occur during exposure in the service environment. In such a situation it is common for the design criteria and

  19. A Hierarchical Control Architecture for a PEBB-Based ILC Marx Modulator

    SciTech Connect (OSTI)

    Macken, K.; Burkhart, C.; Larsen, R.; Nguyen, M.N.; Olsen, J.; /SLAC

    2011-12-15

    The idea of building power conversion systems around Power Electronic Building Blocks (PEBBs) was initiated by the U.S. Office of Naval Research in the mid 1990s. A PEBB-based design approach is advantageous in terms of power density, modularity, reliability, and serviceability. It is obvious that this approach has much appeal for pulsed power conversion including the International Linear Collider (ILC) klystron modulator application. A hierarchical control architecture has the inherent capability to support the integration of PEBBs. This has already been successfully demonstrated in a number of industrial applications in the recent past. This paper outlines the underlying concepts of a hierarchical control architecture for a PEBB-based Marx-topology ILC klystron modulator. The control in PEBB-based power conversion systems can be functionally partitioned into (three) hierarchical layers; system layer, application layer, and PEBB layer. This has been adopted here. Based on such a hierarchical partition, the interfaces are clearly identified and defined and, consequently, are easily characterised. A conceptual design of the hardware manager, executing low-level hardware oriented tasks, is detailed. In addition, the idea of prognostics is briefly discussed.

  20. Design of a superconducting 28 GHz ion source magnet for FRIB using a shell-based support structure

    SciTech Connect (OSTI)

    Felice, H.; Rochepault, E.; Hafalia, R.; Caspi, S.; Dietderich, D. R.; Prestemon, S. O.; Machicoane, G.; Pozdeyev, E.; Bultman, N.; Rao, X.

    2014-12-05

    The Superconducting Magnet Program at the Lawrence Berkeley National Laboratory (LBNL) is completing the design of a 28 GHz NbTi ion source magnet for the Facility for Rare Isotope Beams (FRIB). The design parameters are based on the parameters of the ECR ion source VENUS in operation at LBNL since 2002 featuring a sextupole-in-solenoids configuration. Whereas most of the magnet components (such as conductor, magnetic design, protection scheme) remain very similar to the VENUS magnet components, the support structure of the FRIB ion source uses a different concept. A shell-based support structure using bladders and keys is implemented in the design allowing fine tuning of the sextupole preload and reversibility of the magnet assembly process. As part of the design work, conductor insulation scheme, coil fabrication processes and assembly procedures are also explored to optimize performance. We present the main features of the design emphasizing the integrated design approach used at LBNL to achieve this result.

  1. Magnetic and Structural Design of a 15 T $Nb_3Sn$ Accelerator Depole Model

    SciTech Connect (OSTI)

    Kashikhin, V. V.; Andreev, N.; Barzi, E.; Novitski, I.; Zlobin, A. V.

    2015-01-01

    Hadron Colliders (HC) are the most powerful discovery tools in modern high energy physics. A 100 TeV scale HC with a nominal operation field of at least 15 T is being considered for the post-LHC era. The choice of a 15 T nominal field requires using the Nb3Sn technology. Practical demonstration of this field level in an accelerator-quality magnet and substantial reduction of the magnet costs are the key conditions for realization of such a machine. FNAL has started the development of a 15 T $Nb_{3}Sn$ dipole demonstrator for a 100 TeV scale HC. The magnet design is based on 4-layer shell type coils, graded between the inner and outer layers to maximize the performance. The experience gained during the 11-T dipole R&D campaign is applied to different aspects of the magnet design. This paper describes the magnetic and structural designs and parameters of the 15 T $Nb_3Sn$ dipole and the steps towards the demonstration model.

  2. Impact of photonic crystals on LED light extraction efficiency: approaches and limits to vertical structure designs

    SciTech Connect (OSTI)

    Matioli, Elison; Weisbuch, Claude

    2010-08-19

    The enhancement of the extraction efficiency in light emitting diodes (LEDs) through the use of photonic crystals (PhCs) requires a structure design that optimizes the interaction of the guided modes with the PhCs. The main optimization parameters are related to the vertical structure of the LED, such as the thickness of layers, depth of the PhCs, position of the quantum wells as well as the PhC period and fill factor. We review the impact of the vertical design of different approaches of PhC LEDs through a theoretical and experimental standpoint, assessing quantitatively the competing mechanisms that act over each guided mode. Three approaches are described to overcome the main limitation of LEDs with surface PhCs, i.e. the insufficient interaction of low order guided modes with the PhCs. The introduction of an AlGaN confining layer in such structure is shown to be effective in extracting a fraction of the optical energy of low order modes; however, this approach is limited by the growth of the lattice mismatched AlGaN layer on GaN. The second approach, based on thin-film LEDs with PhCs, is limited by the presence of an absorbing reflective metal layer close to the guided modes that plays a major role in the competition between PhC extraction and metal dissipation. Finally, we demonstrate both experimentally and theoretically the superior extraction of the guided light in embedded PhC LEDs due to the higher interaction between all optical modes and the PhCs, which resulted in a close to unity extraction efficiency for this device. The use of high-resolution angle-resolved measurements to experimentally determine the PhC extraction parameters was an essential tool for corroborating the theoretical models and quantifying the competing absorption and extraction mechanisms in LEDs.

  3. Technique for fast and efficient hierarchical clustering

    DOE Patents [OSTI]

    Stork, Christopher

    2013-10-08

    A fast and efficient technique for hierarchical clustering of samples in a dataset includes compressing the dataset to reduce a number of variables within each of the samples of the dataset. A nearest neighbor matrix is generated to identify nearest neighbor pairs between the samples based on differences between the variables of the samples. The samples are arranged into a hierarchy that groups the samples based on the nearest neighbor matrix. The hierarchy is rendered to a display to graphically illustrate similarities or differences between the samples.

  4. Support structure design of the Nb?Sn quadrupole for the high luminosity LHC

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

    Juchno, M.; Anerella, M.; Ambrosio, G.; Cheng, D.; Felice, H.; Ferracin, P.; Perez, J. C.; Prin, H.; Schmalzle, J.

    2014-10-31

    New low-? quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb?Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of themoredetailed 3D numerical analysis performed in preparation for the first short model test.less

  5. Uniform hierarchical SnS microspheres: Solvothermal synthesis and lithium ion storage performance

    SciTech Connect (OSTI)

    Fang, Zhen Wang, Qin; Wang, Xiaoqing; Fan, Fan; Wang, Chenyan; Zhang, Xiaojun

    2013-11-15

    Graphical abstract: - Highlights: Uniform hierarchical SnS microspheres via solvothermal reaction. The formation process was investigated in detail. The obtained hierarchical SnS microspheres exhibit superior capacity (1650 mAh g{sup ?1}) when used as lithium battery for the hierarchical microsphere structure. - Abstract: Hierarchical SnS microspheres have been successfully synthesized by a mild solvothermal process using poly(vinylpyrrolidone) as surfactant in this work. The morphology and composition of the microspheres were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The influence of reaction parameters, such as sulfur sources, reaction temperature and the concentration of PVP, on the final morphology of the products are investigated. On the basis of time-dependent experiments, the growth mechanism has also been proposed. The specific surface area of the 3D hierarchitectured SnS microspheres were investigated by using nitrogen adsorption and desorption isotherms. Lithium ion storage performances of the synthesized materials as anodes for Lithium-ion battery were investigated in detail and it exhibits excellent electrochemical properties.

  6. Hierarchical electrode architectures for electrical energy storage & conversion.

    SciTech Connect (OSTI)

    Zavadil, Kevin Robert; Missert, Nancy A.; Shelnutt, John Allen; van Swol, Frank B.

    2012-01-01

    The integration and stability of electrocatalytic nanostructures, which represent one level of porosity in a hierarchical structural scheme when combined with a three-dimensional support scaffold, has been studied using a combination of synthetic processes, characterization techniques, and computational methods. Dendritic platinum nanostructures have been covalently linked to common electrode surfaces using a newly developed chemical route; a chemical route equally applicable to a range of metals, oxides, and semiconductive materials. Characterization of the resulting bound nanostructure system confirms successful binding, while electrochemistry and microscopy demonstrate the viability of these electroactive particles. Scanning tunneling microscopy has been used to image and validate the short-term stability of several electrode-bound platinum dendritic sheet structures toward Oswald ripening. Kinetic Monte Carlo methods have been applied to develop an understanding of the stability of the basic nano-scale porous platinum sheets as they transform from an initial dendrite to hole containing sheets. Alternate synthetic strategies were pursued to grow dendritic platinum structures directly onto subunits (graphitic particles) of the electrode scaffold. A two-step photocatalytic seeding process proved successful at generating desirable nano-scale porous structures. Growth in-place is an alternate strategy to the covalent linking of the electrocatalytic nanostructures.

  7. Structural Design and Thermal Analysis for Thermal Shields of the MICE Coupling Magnets

    SciTech Connect (OSTI)

    Green, Michael A.; Pan, Heng; Liu, X. K.; Wang, Li; Wu, Hong; Chen, A. B.; Guo, X.L.

    2009-07-01

    A superconducting coupling magnet made from copper matrix NbTi conductors operating at 4 K will be used in the Muon Ionization Cooling Experiment (MICE) to produce up to 2.6 T on the magnet centerline to keep the muon beam within the thin RF cavity indows. The coupling magnet is to be cooled by two cryocoolers with a total cooling capacity of 3 W at 4.2 K. In order to keep a certain operating temperature margin, the most important is to reduce the heat leakage imposed on cold surfaces of coil cold mass assembly. An ntermediate temperature shield system placed between the coupling coil and warm vacuum chamber is adopted. The shield system consists of upper neck shield, main shields, flexible connections and eight supports, which is to be cooled by the first stage cold heads of two ryocoolers with cooling capacity of 55 W at 60 K each. The maximum temperature difference on the shields should be less than 20 K, so the thermal analyses for the shields with different thicknesses, materials, flexible connections for shields' cooling and structure design for heir supports were carried out. 1100 Al is finally adopted and the maximum temperature difference is around 15 K with 4 mm shield thickness. The paper is to present detailed analyses on the shield system design.

  8. Composite structures 4; Proceedings of the Fourth International Conference, Paisley College of Technology, Scotland, July 27-29, 1987. Volume 1 - Analysis and design studies

    SciTech Connect (OSTI)

    Marshall, I.H.

    1987-01-01

    Various papers on analysis and design studies in composite structures are presented. The general topics addressed include: space studies, mechanical fasteners, buckling and postbuckling of platework structures, aerospace structures, wind turbine design, pipes and pressure vessels, analysis and buckling of shell-type structures. Also considered are: structural sections and optimization, thermal loading, vibration of platework structures and shell-type structures, dynamic loading, and finite element analysis.

  9. Crystal Structures of Aureochrome1 LOV Suggest New Design Strategies for Optogenetics

    SciTech Connect (OSTI)

    Mitra, Devrani; Yang, Xiaojing; Moffat, Keith

    2014-10-02

    Aureochrome1, a signaling photoreceptor from a eukaryotic photosynthetic stramenopile, confers blue-light-regulated DNA binding on the organism. Its topology, in which a C-terminal LOV sensor domain is linked to an N-terminal DNA-binding bZIP effector domain, contrasts with the reverse sensor-effector topology in most other known LOV-photoreceptors. How, then, is signal transmitted in Aureochrome1? The dark- and light-state crystal structures of Aureochrome1 LOV domain (AuLOV) show that its helical N- and C-terminal flanking regions are packed against the external surface of the core {beta} sheet, opposite to the FMN chromophore on the internal surface. Light-induced conformational changes occur in the quaternary structure of the AuLOV dimer and in Phe298 of the H{beta} strand in the core. The properties of AuLOV extend the applicability of LOV domains as versatile design modules that permit fusion to effector domains via either the N- or C-termini to confer blue-light sensitivity.

  10. Oracle Database DBFS Hierarchical Storage Overview

    SciTech Connect (OSTI)

    Rivenes, A

    2011-07-25

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory creates large numbers of images during each shot cycle for the analysis of optics, target inspection and target diagnostics. These images must be readily accessible once they are created and available for the 30 year lifetime of the facility. The Livermore Computing Center (LC) runs a High Performance Storage System (HPSS) that is capable of storing NIF's estimated 1 petabyte of diagnostic images at a fraction of what it would cost NIF to operate its own automated tape library. With Oracle 11g Release 2 database, it is now possible to create an application transparent, hierarchical storage system using the LC's HPSS. Using the Oracle DBMS-LOB and DBMS-DBFS-HS packages a SecureFile LOB can now be archived to storage outside of the database and accessed seamlessly through a DBFS 'link'. NIF has chosen to use this technology to implement a hierarchical store for its image based SecureFile LOBs. Using a modified external store and DBFS links, files are written to and read from a disk 'staging area' using Oracle's backup utility. Database external procedure calls invoke OS based scripts to manage a staging area and the transfer of the backup files between the staging area and the Lab's HPSS.

  11. Prospects for the pulsed electrodeposition of zinc-oxide hierarchical nanostructures

    SciTech Connect (OSTI)

    Klochko, N. P.; Myagchenko, Y. O.; Melnychuk, E. E.; Kopach, V. R.; Klepikova, E. S.; Lyubov, V. N.; Khrypunov, G. S.; Kopach, A. V.

    2013-08-15

    Studies into the effect of the conditions of pulsed electrodeposition upon the structural and sub-structural parameters, morphology, and optical properties of ZnO-crystallite arrays make it possible to establish those parameters optimal for the formation of ZnO nanorods oriented normally to the substrate surface. These parameters are as follows: an electrolyte temperature of 70-85 Degree-Sign C, duty cycle of 40%, and a pulse-repetition frequency of 2 Hz. The nanorod dimensions can be varied by heating or cooling the electrolyte within the above-indicated limits; as a result, small-sized nanorods can be electrically deposited on the surface of larger nanorods to form hierarchical nanostructures. By varying the duty cycle, it is possible to modify the surface morphology of the arrays up to the formation of mesoporous ZnO networks. In combination with ZnO nanorods, such networks are capable of forming hierarchical nanostructures with large specific areas.

  12. Hierarchical clustering using correlation metric and spatial continuity constraint

    DOE Patents [OSTI]

    Stork, Christopher L.; Brewer, Luke N.

    2012-10-02

    Large data sets are analyzed by hierarchical clustering using correlation as a similarity measure. This provides results that are superior to those obtained using a Euclidean distance similarity measure. A spatial continuity constraint may be applied in hierarchical clustering analysis of images.

  13. Hierarchical image segmentation for learning object priors

    SciTech Connect (OSTI)

    Prasad, Lakshman; Yang, Xingwei; Latecki, Longin J; Li, Nan

    2010-11-10

    The proposed segmentation approach naturally combines experience based and image based information. The experience based information is obtained by training a classifier for each object class. For a given test image, the result of each classifier is represented as a probability map. The final segmentation is obtained with a hierarchial image segmentation algorithm that considers both the probability maps and the image features such as color and edge strength. We also utilize image region hierarchy to obtain not only local but also semi-global features as input to the classifiers. Moreover, to get robust probability maps, we take into account the region context information by averaging the probability maps over different levels of the hierarchical segmentation algorithm. The obtained segmentation results are superior to the state-of-the-art supervised image segmentation algorithms.

  14. Fluorocarbon Adsorption in Hierarchical Porous Frameworks

    SciTech Connect (OSTI)

    Motkuri, Radha K.; Annapureddy, Harsha V.; Vijayakumar, M.; Schaef, Herbert T.; Martin, P F.; McGrail, B. Peter; Dang, Liem X.; Krishna, Rajamani; Thallapally, Praveen K.

    2014-07-09

    The adsorption behavior of a series of fluorocarbon derivatives was examined on a set of microporous metal organic framework (MOF) sorbents and another set of hierarchical mesoporous MOFs. The microporous M-DOBDC (M = Ni, Co) showed a saturation uptake capacity for R12 of over 4 mmol/g at a very low relative saturation pressure (P/Po) of 0.02. In contrast, the mesoporous MOF MIL-101 showed an exceptionally high uptake capacity reaching over 14 mmol/g at P/Po of 0.4. Adsorption affinity in terms of mass loading and isosteric heats of adsorption were found to generally correlate with the polarizability of the refrigerant with R12 > R22 > R13 > R14 > methane. These results suggest the possibility of exploiting MOFs for separation of azeotropic mixtures of fluorocarbons and use in eco-friendly fluorocarbon-based adsorption cooling and refrigeration applications.

  15. Structural Design Criteria for Anion Hosts: Strategies for Achieving Anion Shape Recognition through the Complementary Placement of Urea Donor Groups

    SciTech Connect (OSTI)

    Hay, Benjamin P.; Firman, Timothy K.; Moyer, Bruce A.

    2005-02-16

    The arrangement of urea ligands about different shaped anions has been evaluated with electronic structure calculations. Geometries and binding energies are reported for urea complexes with Cl{sup -}, NO{sub 3}{sup -}, and ClO{sub 4}{sup -}. The results yield new insight into the nature of urea-anion interactions and provide structural criteria for the deliberate design of anion selective receptors containing two or more urea donor groups.

  16. Breakdown of hierarchical architecture in cellulose during dilute acid pretreatments

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

    Zhang, Yan; Inouye, Hideyo; Yang, Lin; Himmel, Michael E.; Tucker, Melvin; Makowski, Lee

    2015-02-28

    Cellulose is an attractive candidate as a feedstock for sustainable bioenergy because of its global abundance. Pretreatment of biomass has significant influence on the chemical availability of cellulose locked in recalcitrant microfibrils. Optimizing pretreatment depends on an understanding of its impact on the microscale and nanoscale molecular architecture. X-ray scattering experiments have been performed on native and pre-treated maize stover and models of cellulose architecture have been derived from these data. Ultra small-angle, very small-angle and small-angle X-ray scattering (USAXS, VSAXS and SAXS) probe three different levels of architectural scale. USAXS and SAXS have been used to study cellulose atmore » two distinct length scales, modeling the fibrils as ~30 Å diameter rods packed into ~0.14 μm diameter bundles. VSAXS is sensitive to structural features at length scales between these two extremes. Detailed analysis of diffraction patterns from untreated and pretreated maize using cylindrical Guinier plots and the derivatives of these plots reveals the presence of substructures within the ~0.14 μm diameter bundles that correspond to grouping of cellulose approximately 30 nm in diameter. These sub-structures are resilient to dilute acid pretreatments but are sensitive to pretreatment when iron sulfate is added. Lastly, these results provide evidence of the hierarchical arrangement of cellulose at three length scales and the evolution of these arrangements during pre-treatments.« less

  17. Breakdown of hierarchical architecture in cellulose during dilute acid pretreatments

    SciTech Connect (OSTI)

    Zhang, Yan; Inouye, Hideyo; Yang, Lin; Himmel, Michael E.; Tucker, Melvin; Makowski, Lee

    2015-02-28

    Cellulose is an attractive candidate as a feedstock for sustainable bioenergy because of its global abundance. Pretreatment of biomass has significant influence on the chemical availability of cellulose locked in recalcitrant microfibrils. Optimizing pretreatment depends on an understanding of its impact on the microscale and nanoscale molecular architecture. X-ray scattering experiments have been performed on native and pre-treated maize stover and models of cellulose architecture have been derived from these data. Ultra small-angle, very small-angle and small-angle X-ray scattering (USAXS, VSAXS and SAXS) probe three different levels of architectural scale. USAXS and SAXS have been used to study cellulose at two distinct length scales, modeling the fibrils as ~30 Å diameter rods packed into ~0.14 μm diameter bundles. VSAXS is sensitive to structural features at length scales between these two extremes. Detailed analysis of diffraction patterns from untreated and pretreated maize using cylindrical Guinier plots and the derivatives of these plots reveals the presence of substructures within the ~0.14 μm diameter bundles that correspond to grouping of cellulose approximately 30 nm in diameter. These sub-structures are resilient to dilute acid pretreatments but are sensitive to pretreatment when iron sulfate is added. Lastly, these results provide evidence of the hierarchical arrangement of cellulose at three length scales and the evolution of these arrangements during pre-treatments.

  18. Synthesis of BiOI flowerlike hierarchical structures toward photocatal...

    Office of Scientific and Technical Information (OSTI)

    OSTI Identifier: 22348668 Resource Type: Journal Article Resource Relation: Journal Name: Materials Research Bulletin; Journal Volume: 55; Other Information: Copyright (c) 2014 ...

  19. Design of a superconducting 28 GHz ion source magnet for FRIB using a shell-based support structure

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

    Felice, H.; Rochepault, E.; Hafalia, R.; Caspi, S.; Dietderich, D. R.; Prestemon, S. O.; Machicoane, G.; Pozdeyev, E.; Bultman, N.; Rao, X.

    2014-12-05

    The Superconducting Magnet Program at the Lawrence Berkeley National Laboratory (LBNL) is completing the design of a 28 GHz NbTi ion source magnet for the Facility for Rare Isotope Beams (FRIB). The design parameters are based on the parameters of the ECR ion source VENUS in operation at LBNL since 2002 featuring a sextupole-in-solenoids configuration. Whereas most of the magnet components (such as conductor, magnetic design, protection scheme) remain very similar to the VENUS magnet components, the support structure of the FRIB ion source uses a different concept. A shell-based support structure using bladders and keys is implemented in themore » design allowing fine tuning of the sextupole preload and reversibility of the magnet assembly process. As part of the design work, conductor insulation scheme, coil fabrication processes and assembly procedures are also explored to optimize performance. We present the main features of the design emphasizing the integrated design approach used at LBNL to achieve this result.« less

  20. Model Based Structural Evaluation & Design of Overpack Container for Bag-Buster Processing of TRU Waste Drums

    SciTech Connect (OSTI)

    D. T. Clark; A. S. Siahpush; G. L. Anderson

    2004-07-01

    This paper describes a materials and computational model based analysis utilized to design an engineered overpack container capable of maintaining structural integrity for confinement of transuranic wastes undergoing the cryo-vacuum stress based Bag-Buster process and satisfying DOT 7A waste package requirements. The engineered overpack is a key component of the Ultra-BagBuster process/system being commercially developed by UltraTech International for potential DOE applications to non-intrusively breach inner confinement layers (poly bags/packaging) within transuranic (TRU) waste drums. This system provides a lower cost/risk approach to mitigate hydrogen gas concentration buildup limitations on transport of high alpha activity organic transuranic wastes. Four evolving overpack design configurations and two materials (low carbon steel and 300 series stainless) were considered and evaluated using non-linear finite element model analyses of structural response. Properties comparisons show that 300-series stainless is required to provide assurance of ductility and structural integrity at both room and cryogenic temperatures. The overpack designs were analyzed for five accidental drop impact orientations onto an unyielding surface (dropped flat on bottom, bottom corner, side, top corner, and top). The first three design configurations failed the bottom and top corner drop orientations (flat bottom, top, and side plates breached or underwent material failure). The fourth design utilized a protruding rim-ring (skirt) below the overpacks bottom plate and above the overpacks lid plate to absorb much of the impact energy and maintained structural integrity under all accidental drop loads at both room and cryogenic temperature conditions. Selected drop testing of the final design will be required to confirm design performance.

  1. A Multi-layer, Hierarchical Information Management System for the Smart Grid

    SciTech Connect (OSTI)

    Lu, Ning; Du, Pengwei; Paulson, Patrick R.; Greitzer, Frank L.; Guo, Xinxin; Hadley, Mark D.

    2011-10-10

    This paper presents the modeling approach, methodologies, and initial results of setting up a multi-layer, hierarchical information management system (IMS) for the smart grid. The IMS allows its users to analyze the data collected by multiple control and communication networks to characterize the states of the smart grid. Abnormal, corrupted, or erroneous measurement data and outliers are detected and analyzed to identify whether they are caused by random equipment failures, unintentional human errors, or deliberate tempering attempts. Data collected from different information networks are crosschecked for data integrity based on redundancy, dependency, correlation, or cross-correlations, which reveal the interdependency between data sets. A hierarchically structured reasoning mechanism is used to rank possible causes of an event to aid the system operators to proactively respond or provide mitigation recommendations to remove or neutralize the threats. The model provides satisfactory performance on identifying the cause of an event and significantly reduces the need of processing myriads of data collected.

  2. TAOI B- Computational Microstructural Optimization Design Tool for High Temperature Structural Materials

    SciTech Connect (OSTI)

    Mishra, Rajiv; Charit, Indrajit

    2015-02-28

    The objectives of this research were two-fold: (a) develop a methodology for microstructural optimization of alloys - genetic algorithm approach for alloy microstructural optimization using theoretical models based on fundamental micro-mechanisms, and (b) develop a new computationally designed Ni-Cr alloy for coal-fired power plant applications. The broader outcome of these objectives is expected to be creation of an integrated approach for ‘structural materials by microstructural design’. Three alloy systems were considered for computational optimization and validation, (i) Ni-20Cr (wt.%) base alloy using only solid solution strengthening, (ii) nano-Y2O3 containing Ni-20Cr-1.2Y2O3 (wt.%) alloy for dispersion strengthening and (iii) a sub-micron Al2O3 for composite strengthening, Ni-20Cr-1.2Y2O3-5.0Al2O3 (wt.%). The specimens were synthesized by mechanical alloying and consolidated using spark plasma sintering. Detailed microstructural characterization was done along with initial mechanical properties to validate the computational prediction. A key target property is to have creep rate of 1x10-9 s-1 at 100 MPa and 800oC. The initial results were quite promising and require additional quantification of strengthening contributions from dislocation-particle attractive interaction and load transfer. The observed creep rate was in order of 10-9 s-1 for longer time creep test of Ni-20Cr -1.2Y2O3-5Al2O3, lending support to the overall approach pursued in this project.

  3. Constitutional Isomers of Dendrimer-like Star Polymers: Design, Synthesis and Conformational and Structural Properties

    SciTech Connect (OSTI)

    Pople, John A.

    2001-03-22

    The design, synthesis and solution properties of six constitutional isomers of dendrimer-like star polymers is described. Each of the polymers have comparable molecular weights ({approx} 80,000 g/mol), narrow polydispersities (< 1.19) and an identical number of branching junctures (45) and surface hydroxyl functionalities (48). The only difference in the six isomers is the placement of the branching junctures. The polymers are constructed from high molecular weight poly(e-caprolactone) with branching junctures derived from 2,2'-bis(hydroxylmethyl) propionic acid (bis-MPA) emanating from a central core. The use of various generations of dendritic initiators and dendrons coupled with the ring opening polymerization of e-caprolactones allowed a modular approach to the dendrimer-like star polymer isomers. The most pronounced effects on the physical properties/morphology and hydrodynamic volume was for those polymers in which the branching was distributed throughout the sample in a dendrimer-like fashion. The versatility of this approach has provided the possibility of understanding the relationship between architecture and physical properties. Dynamic light scattering and small angle X-ray scattering techniques were used to determine the hydrodynamic radius Rh and radius of gyration Rg respectively. The relationship between Rg and molecular weight was indicative of a compact star-like structure, and did not show advanced bias towards either the dense core or dense shell models. The radial density distribution of the isomers was therefore modeled according to a many arm star polymer, and good agreement was found with experimental measures of Rh/Rg.

  4. Seismic design technology for breeder reactor structures. Volume 2. Special topics in soil/structure interaction analyses

    SciTech Connect (OSTI)

    Reddy, D.P.

    1983-04-01

    This volume is divided into six chapters: definition of seismic input ground motion, review of state-of-the-art procedures, analysis guidelines, rock/structure interaction analysis example, comparison of two- and three-dimensional analyses, and comparison of analyses using FLUSH and TRI/SAC Codes. (DLC)

  5. Design and Fabrication of a Supporting Structure for 3.6m Long Nb3Sn Racetrack Coils

    SciTech Connect (OSTI)

    Ambrosio, G.; Anerella, M.; Barzi, E.; Caspi, Shlomo; Cheng, Daniel; Dietderich, Daniel; Gourlay, Steve; Hafalia, A. Ray; Hannaford, Charles; Lietzke, Alan; Nobrega, A.R.; Sabbi, GianLuca; Schmalzle, J.; Wanderer, R. J; Zlobin, A.V.; Ferracin, P.

    2007-06-01

    As part of the LHC Accelerator Research Program (LARP), three US national laboratories (BNL, FNAL, and LBNL) are currently engaged in the development of superconducting magnets for the LHC Interaction Regions (IR) beyond the current design. As a first step towards the development of long Nb{sub 3}Sn quadrupole magnets, a 3.6 m long structure, based on the LBNL Subscale Common-Coil Magnet design, will be fabricated, assembled, and tested with aluminum-plate 'dummy coils'. The structure features an aluminum shell pre-tensioned over iron yokes using pressurized bladders and locking keys (bladder and key technology). Pre-load homogeneity and mechanical responses are monitored with pressure sensitive films and strain gauges mounted on the aluminum shell and the dummy coils. The details of the design and fabrication are presented and discussed, and the expected mechanical behavior is analyzed with finite element models.

  6. Growth, characterization and electrochemical properties of hierarchical CuO nanostructures for supercapacitor applications

    SciTech Connect (OSTI)

    Krishnamoorthy, Karthikeyan; Kim, Sang-Jae

    2013-09-01

    Graphical abstract: - Highlights: Hierarchical CuO nanostructures were grown on Cu foil. Monoclinic phase of CuO was grown. XPS analysis revealed the presence of Cu(2p{sub 3/2}) and Cu(2p{sub 1/2}) on the surfaces. Specific capacitance of 94 F/g was achieved for the CuO using cyclic voltammetry. Impedance spectra show their pseudo capacitor applications. - Abstract: In this paper, we have investigated the electrochemical properties of hierarchical CuO nanostructures for pseudo-supercapacitor device applications. Moreover, the CuO nanostructures were formed on Cu substrate by in situ crystallization process. The as-grown CuO nanostructures were characterized using X-ray diffraction (XRD), Fourier transform-infra red spectroscopy (FT-IR), X-ray photoelectron spectroscopy and field emission-scanning electron microscope (FE-SEM) analysis. The XRD and FT-IR analysis confirm the formation of monoclinic CuO nanostructures. FE-SEM analysis shows the formation of leave like hierarchical structures of CuO with high uniformity and controlled density. The electrochemical analysis such as cyclic voltammetry and electrochemical impedance spectroscopy studies confirms the pseudo-capacitive behavior of the CuO nanostructures. Our experimental results suggest that CuO nanostructures will create promising applications of CuO toward pseudo-supercapacitors.

  7. Structural Design Considerations for Tubular Power Tower Receivers Operating at 650 Degrees C: Preprint

    SciTech Connect (OSTI)

    Neises, T. W.; Wagner, M. J.; Gray, A. K.

    2014-04-01

    Research of advanced power cycles has shown supercritical carbon dioxide power cycles may have thermal efficiency benefits relative to steam cycles at temperatures around 500 - 700 degrees C. To realize these benefits for CSP, it is necessary to increase the maximum outlet temperature of current tower designs. Research at NREL is investigating a concept that uses high-pressure supercritical carbon dioxide as the heat transfer fluid to achieve a 650 degrees C receiver outlet temperature. At these operating conditions, creep becomes an important factor in the design of a tubular receiver and contemporary design assumptions for both solar and traditional boiler applications must be revisited and revised. This paper discusses lessons learned for high-pressure, high-temperature tubular receiver design. An analysis of a simplified receiver tube is discussed, and the results show the limiting stress mechanisms in the tube and the impact on the maximum allowable flux as design parameters vary. Results of this preliminary analysis indicate an underlying trade-off between tube thickness and the maximum allowable flux on the tube. Future work will expand the scope of design variables considered and attempt to optimize the design based on cost and performance metrics.

  8. Design of RF Feed System for Standing-Wave Accelerator Structures

    SciTech Connect (OSTI)

    Neilson, J.; Tantawi, S.; Dolgashev, V.; /SLAC

    2012-05-25

    We are investigating a standing wave accelerator structure that uses a rf feed to each individual cell. This approach minimizes rf power flow and electromagnetic energy absorbed by an rf breakdown. The objective of this work is a robust high-gradient (above 100 MV/m) X-band accelerator structure.

  9. Design of RF Feed System for Standing-Wave Accelerator Structures

    SciTech Connect (OSTI)

    Neilson, Jeffrey; Tantawi, Sami; Dolgashev, Valery

    2010-11-04

    We are investigating a standing wave structure with an rf feed to each individual cell. This approach minimizes rf power flow and electromagnetic energy absorbed by an rf breakdown. The objective of this work is a robust high-gradient (above 100 MV/m) X-band accelerator structure.

  10. Facile route to hierarchical silver microstructures with high catalytic activity for the reduction of p-nitrophenol

    SciTech Connect (OSTI)

    Gu, Sasa; Wang, Wei Tan, Fatang; Gu, Jian; Qiao, Xueliang; Chen, Jianguo

    2014-01-01

    Graphical abstract: - Highlights: • A facile route was developed to prepare hierarchical silver microstructures. • The shape and size of secondary units can be tailed by varying reaction conditions. • Hierarchical silver microstructures have excellent catalytic activity. • The morphology and crystallinity of silver particles affect the catalytic activity. - Abstract: A facile, cost-effective and environmentally friendly route was developed to synthesize hierarchical silver microstructures consisting of different shaped secondary units through reducing concentrated silver nitrate with ascorbic acid in the absence of any surfactant. The as-obtained samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The investigation on the morphology evolution revealed that the molar ratio of ascorbic acid to silver nitrate was critical to control the shape of secondary structures. The length of plate-like secondary structures which composed hierarchical silver particles could be controlled by changing the reactant concentrations, and it had a key relationship with the catalytic activity for the reduction of p-nitrophenol by NaBH{sub 4}. The catalytic activity of these surfactant-free silver microstructures was about ten times higher than that of silver nanoparticles, and even comparable to that of gold nanoplates, which indicates that the as-obtained silver microstructures are very promising candidates for the catalytic reduction of p-nitrophenol due to the simple synthesis route and high catalytic activity.

  11. Federal and State Structures to Support Financing Utility-Scale Solar Projects and the Business Models Designed to Utilize Them

    SciTech Connect (OSTI)

    Mendelsohn, M.; Kreycik, C.

    2012-04-01

    Utility-scale solar projects have grown rapidly in number and size over the last few years, driven in part by strong renewable portfolio standards (RPS) and federal incentives designed to stimulate investment in renewable energy technologies. This report provides an overview of such policies, as well as the project financial structures they enable, based on industry literature, publicly available data, and questionnaires conducted by the National Renewable Energy Laboratory (NREL).

  12. Structure-Based Design of Potent and Ligand-Efficient Inhibitors of CTX-M Class A [beta]-Lactamase

    SciTech Connect (OSTI)

    Nichols, Derek A.; Jaishankar, Priyadarshini; Larson, Wayne; Smith, Emmanuel; Liu, Guoqing; Beyrouthy, Racha; Bonnet, Richard; Renslo, Adam R.; Chen, Yu

    2012-07-11

    The emergence of CTX-M class A extended-spectrum {beta}-lactamases poses a serious health threat to the public. We have applied structure-based design to improve the potency of a novel noncovalent tetrazole-containing CTX-M inhibitor (K{sub i} = 21 {mu}M) more than 200-fold via structural modifications targeting two binding hot spots, a hydrophobic shelf formed by Pro167 and a polar site anchored by Asp240. Functional groups contacting each binding hot spot independently in initial designs were later combined to produce analogues with submicromolar potencies, including 6-trifluoromethyl-3H-benzoimidazole-4-carboxylic acid [3-(1H-tetrazol-5-yl)-phenyl]-amide, which had a K{sub i} value of 89 nM and reduced the MIC of cefotaxime by 64-fold in CTX-M-9 expressing Escherichia coli. The in vitro potency gains were accompanied by improvements in ligand efficiency (from 0.30 to 0.39) and LipE (from 1.37 to 3.86). These new analogues represent the first nM-affinity noncovalent inhibitors of a class A {beta}-lactamase. Their complex crystal structures provide valuable information about ligand binding for future inhibitor design.

  13. Dispersed metal cluster catalysts by design. Synthesis, characterization, structure, and performance

    SciTech Connect (OSTI)

    Arslan, Ilke; Dixon, David A.; Gates, Bruce C.; Katz, Alexander

    2015-09-30

    To understand the class of metal cluster catalysts better and to lay a foundation for the prediction of properties leading to improved catalysts, we have synthesized metal catalysts with well-defined structures and varied the cluster structures and compositions systematically—including the ligands bonded to the metals. These ligands include supports and bulky organics that are being tuned to control both the electron transfer to or from the metal and the accessibility of reactants to influence catalytic properties. We have developed novel syntheses to prepare these well-defined catalysts with atomic-scale control the environment by choice and placement of ligands and applied state-of-the art spectroscopic, microscopic, and computational methods to determine their structures, reactivities, and catalytic properties. The ligands range from nearly flat MgO surfaces to enveloping zeolites to bulky calixarenes to provide controlled coverages of the metal clusters, while also enforcing unprecedented degrees of coordinative unsaturation at the metal site—thereby facilitating bonding and catalysis events at exposed metal atoms. With this wide range of ligand properties and our arsenal of characterization tools, we worked to achieve a deep, fundamental understanding of how to synthesize robust supported and ligand-modified metal clusters with controlled catalytic properties, thereby bridging the gap between active site structure and function in unsupported and supported metal catalysts. We used methods of organometallic and inorganic chemistry combined with surface chemistry for the precise synthesis of metal clusters and nanoparticles, characterizing them at various stages of preparation and under various conditions (including catalytic reaction conditions) and determining their structures and reactivities and how their catalytic properties depend on their compositions and structures. Key characterization methods included IR, NMR, and EXAFS spectroscopies to identify

  14. CONCEPTUAL DESIGN REPORT

    SciTech Connect (OSTI)

    ROBINSON,K.

    2006-12-31

    Brookhaven National Laboratory has prepared a conceptual design for a world class user facility for scientific research using synchrotron radiation. This facility, called the ''National Synchrotron Light Source II'' (NSLS-II), will provide ultra high brightness and flux and exceptional beam stability. It will also provide advanced insertion devices, optics, detectors, and robotics, and a suite of scientific instruments designed to maximize the scientific output of the facility. Together these will enable the study of material properties and functions with a spatial resolution of {approx}1 nm, an energy resolution of {approx}0.1 meV, and the ultra high sensitivity required to perform spectroscopy on a single atom. The overall objective of the NSLS-II project is to deliver a research facility to advance fundamental science and have the capability to characterize and understand physical properties at the nanoscale, the processes by which nanomaterials can be manipulated and assembled into more complex hierarchical structures, and the new phenomena resulting from such assemblages. It will also be a user facility made available to researchers engaged in a broad spectrum of disciplines from universities, industries, and other laboratories.

  15. Protein folding and non-conventional drug design: a primer for nuclear structure physicists

    SciTech Connect (OSTI)

    Broglia, R.A. [Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milan (Italy); INFN, Sezione di Milano, Via Celoria 16, I-20133 Milan (Italy); Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark); Tiana, G.; Provasi, D. [Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milan (Italy); INFN, Sezione di Milano, Via Celoria 16, I-20133 Milan (Italy)

    2004-02-27

    Some of the paradigms emerging from the study of the phenomena of phase transitions in finite many-body systems, like e.g. the atomic nucleus can be used at profit to solve the protein folding problem within the framework of simple (although not oversimplified) models. From this solution a paradigm emerges for the design of non-conventional drugs, which inhibit enzymatic action without inducing resistance (mutations). The application of these concepts to the design of an inhibitor to the HIV-protease central in the life cycle of the HIV virus is discussed.

  16. Validation of Methods for Computational Catalyst Design: Geometries, Structures, and Energies of Neutral and Charged Silver Clusters

    SciTech Connect (OSTI)

    Duanmu, Kaining; Truhlar, Donald G.

    2015-04-30

    We report a systematic study of small silver clusters, Agn, Agn+, and Agn–, n = 1–7. We studied all possible isomers of clusters with n = 5–7. We tested 42 exchange–correlation functionals, and we assess these functionals for their accuracy in three respects: geometries (quantitative prediction of internuclear distances), structures (the nature of the lowest-energy structure, for example, whether it is planar or nonplanar), and energies. We find that the ingredients of exchange–correlation functionals are indicators of their success in predicting geometries and structures: local exchange–correlation functionals are generally better than hybrid functionals for geometries; functionals depending on kinetic energy density are the best for predicting the lowest-energy isomer correctly, especially for predicting two-dimensional to three-dimenstional transitions correctly. The accuracy for energies is less sensitive to the ingredient list. Our findings could be useful for guiding the selection of methods for computational catalyst design.

  17. Structural design, analysis, and code evaluation of an odd-shaped pressure vessel

    SciTech Connect (OSTI)

    Rezvani, M.A.; Ziada, H.H.

    1992-12-01

    This paper is the result of an effort to design, analyze and evaluate a rectangular pressure vessel. Normally pressure vessels are designed in circular or spherical shapes to prevent stress concentrations. In this case, because of operational limitations, the choice of vessels was limited to a rectangular pressure box with a removable cover plate. The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code is used as a guideline for pressure containments whose width or depth exceeds 15.24 cm (6.0 in.) and where pressures will exceed 103.4 KPa (15.0 lbf/in[sup 2]). This evaluation used Section VIII of this Code, hereafter referred to as the Code. The dimensions and working pressure of the subject vessel fall within the pressure vessel category of the Code. The Code design guidelines and rules do not directly apply to this vessel. Therefore, finite-element methodology was used to analyze the pressure vessel, and the Code then was used in qualifying the vessel to be stamped to the Code. Section VIII, Division 1 of the Code was used for evaluation. This action was justified by selecting a material for which fatigue damage would not be a concern. The stress analysis results were then chocked against the Code, and the thicknesses adjusted to satisfy Code requirements. Although not directly applicable, the Code design formulas for rectangular vessels were also considered and presented in this study.

  18. Structural design, analysis, and code evaluation of an odd-shaped pressure vessel

    SciTech Connect (OSTI)

    Rezvani, M.A.; Ziada, H.H.

    1992-12-01

    This paper is the result of an effort to design, analyze and evaluate a rectangular pressure vessel. Normally pressure vessels are designed in circular or spherical shapes to prevent stress concentrations. In this case, because of operational limitations, the choice of vessels was limited to a rectangular pressure box with a removable cover plate. The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code is used as a guideline for pressure containments whose width or depth exceeds 15.24 cm (6.0 in.) and where pressures will exceed 103.4 KPa (15.0 lbf/in{sup 2}). This evaluation used Section VIII of this Code, hereafter referred to as the Code. The dimensions and working pressure of the subject vessel fall within the pressure vessel category of the Code. The Code design guidelines and rules do not directly apply to this vessel. Therefore, finite-element methodology was used to analyze the pressure vessel, and the Code then was used in qualifying the vessel to be stamped to the Code. Section VIII, Division 1 of the Code was used for evaluation. This action was justified by selecting a material for which fatigue damage would not be a concern. The stress analysis results were then chocked against the Code, and the thicknesses adjusted to satisfy Code requirements. Although not directly applicable, the Code design formulas for rectangular vessels were also considered and presented in this study.

  19. Designing π-stacked molecular structures to control heat transport through molecular junctions

    SciTech Connect (OSTI)

    Kiršanskas, Gediminas; Li, Qian; Solomon, Gemma C.; Flensberg, Karsten; Leijnse, Martin

    2014-12-08

    We propose and analyze a way of using π stacking to design molecular junctions that either enhance or suppress a phononic heat current, but at the same time remain conductors for an electric current. Such functionality is highly desirable in thermoelectric energy converters, as well as in other electronic components where heat dissipation should be minimized or maximized. We suggest a molecular design consisting of two masses coupled to each other with one mass coupled to each lead. By having a small coupling (spring constant) between the masses, it is possible to either reduce or perhaps more surprisingly enhance the phonon conductance. We investigate a simple model system to identify optimal parameter regimes and then use first principle calculations to extract model parameters for a number of specific molecular realizations, confirming that our proposal can indeed be realized using standard molecular building blocks.

  20. Carbon composition with hierarchical porosity, and methods of preparation

    DOE Patents [OSTI]

    Mayes, Richard T; Dai, Sheng

    2014-10-21

    A method for fabricating a porous carbon material possessing a hierarchical porosity, the method comprising subjecting a precursor composition to a curing step followed by a carbonization step, the precursor composition comprising: (i) a templating component comprised of a block copolymer, (ii) a phenolic component, (iii) a dione component in which carbonyl groups are adjacent, and (iv) an acidic component, wherein said carbonization step comprises heating the precursor composition at a carbonizing temperature for sufficient time to convert the precursor composition to a carbon material possessing a hierarchical porosity comprised of mesopores and macropores. Also described are the resulting hierarchical porous carbon material, a capacitive deionization device in which the porous carbon material is incorporated, as well as methods for desalinating water by use of said capacitive deionization device.

  1. A design-oriented investigation into the collision strength of double-hulled structures

    SciTech Connect (OSTI)

    Ito, H.; Hayashi, K.; Kitano, K.

    1994-12-31

    The installation of a double-hulled structure or equivalent alteration for oil tankers was adopted by IMO (International Maritime Organization) in 1992. There is, however, few practical information on what is the minimum size of a double hull to prevent an oil leak or how the size of a double hull affects the collision strength. To give such information, the effects on the dimensions of the double-hulled structure on the collision strength were investigated quantitatively by means of an analytical method developed by the authors. The effects of the side shell plate thickness, transverse webs thickness, the size of longitudinal stiffeners, the size of transverse web stiffener and the depth of a double-hulled tanker were examined.

  2. HIGH EFFICIENCY STRUCTURAL FLOWTHROUGH ROTOR WITH ACTIVE FLAP CONTROL: VOLUME ONE: PRELIMINARY DESIGN REPORT

    SciTech Connect (OSTI)

    Zuteck, Michael D.; Jackson, Kevin L.; Santos, Richard A.; Chow, Ray; Nordenholz, Thomas R.; Wamble, John Lee

    2015-05-16

    The Zimitar one-piece rotor primary structure is integrated, so balanced thrust and gravity loads flow through the hub region without transferring out of its composite material. Large inner rotor geometry is used since there is no need to neck down to a blade root region and pitch bearing. Rotor control is provided by a highly redundant, five flap system on each blade, sized so that easily handled standard electric linear actuators are sufficient.

  3. Design and operating characteristics of cathodic protection systems associated with large seawater intake reinforced concrete structures in the Arabian Gulf

    SciTech Connect (OSTI)

    Ali, M.; Chaudhary, Z.; Al-Muhid, T.M.M.

    1999-07-01

    The large reinforced concrete seawater intake structures, which are part of a cooling system in several petrochemical plants located in the Arabian Gulf, have been catholically protected to arrest chloride-induced corrosion of the steel reinforcement. The cathodic protection systems have an operating history of 1--5 years. The design and operating features of the cathodic protection systems are described and discussed. Monitoring data of each system collected over the years since commissioning of the systems are described and discussed to evaluate performance of each system.

  4. Recent advances in alloy design of Ni{sub 3}Al alloys for structural use

    SciTech Connect (OSTI)

    Liu, C.T.; George, E.P.

    1996-12-31

    This is a comprehensive review of recent advances in R&D of Ni{sub 3}Al-based alloys for structural use at elevated temperatures in hostile environments. Recent studies indicate that polycrystalline Ni{sub 3}Al is intrinsically quite ductile at ambient temperatures, and its poor tensile ductility and brittle grain-boundary fracture are caused mainly by moisture-induced hydrogen embrittlement when the aluminide is tested in moisture- or hydrogen-containing environments. Tensile ductility is improved by alloying with substitutional and interstitial elements. Among these additives, B is most effective in suppressing environmental embrittlement and enhancing grain-boundary cohesion, resulting in a dramatic increase of tensile ductility at room temperature. Both B-doped and B-free Ni{sub 3}Al alloys exhibit brittle intergranular fracture and low ductility at intermediate temperatures (300-850 C) because of oxygen-induced embrittlement in oxidizing environments. Cr is found to be most effective in alleviating elevated-temperature embrittlement. Parallel efforts on alloy development using physical metallurgy principles have led to development of several Ni{sub 3}Al alloys for industrial use. The unique properties of these alloys are briefly discussed. 56 refs, 15 figs, 3 tabs.

  5. Scalable Computer Performance and Analysis (Hierarchical INTegration)

    Energy Science and Technology Software Center (OSTI)

    1999-09-02

    HINT is a program to measure a wide variety of scalable computer systems. It is capable of demonstrating the benefits of using more memory or processing power, and of improving communications within the system. HINT can be used for measurement of an existing system, while the associated program ANALYTIC HINT can be used to explain the measurements or as a design tool for proposed systems.

  6. Structural Criteria for the Rational Design of Selective Ligands: Convergent Hydrogen Bonding Sites for the Nitrate Anion

    SciTech Connect (OSTI)

    Hay, Benjamin P.; Gutowski, Maciej S.; Dixon, David A.; Garza , Jorge; Vargas, Rubicelia; Moyer, Bruce A.

    2004-06-30

    Molecular hosts for anion complexation are often constructed by combining two or more hydrogen bonding functional groups, DH. The deliberate design of complementary host architectures requires knowledge of the optimal geometry for the hydrogen bonds formed between the host and the guest. Herein, we present a detailed study of the structural aspects of hydrogen bonding interactions with the NO3 anion. A large number of crystal structures are analyzed to determine the number of hydrogen bond contacts per anion and to further characterize the structural aspects of these interactions. Electronic structure calculations are used to determine stable geometries and interaction energies for NO3 complexes with several simple molecules possessing DH groups, including water, methanol, N-methylformamide, and methane. Theoretical results are reported at several levels of density functional theory, including BP86/DN**, B3LYP/TZVP, and B3LYP/TZVP+, and at MP2/aug-cc-pVDZ. In addition, MP2 binding energies for these complexes were obtained at the complete basis set limit by extrapolating from single point energies obtained with larger correlation-consistent basis sets. The results establish that NO3 has an intrinsic hydrogen bonding topography in which there are six optimal sites for proton location. The structural features observed in crystal structures and in the optimized geometries of complexes are explained by a preference to locate the DH protons in these positions. For the strongest hydrogen bonding interactions, the NOH angle is bent at an angle of 115 10, and the hydrogen atom lies in the NO3 plane giving ONOH dihedral angles of 0 and 180. In addition, the D-H vector points towards the oxygen atom, giving DHO angles that are near linear, 170 10. Due to steric hindrance, simple alcohol OH and amide NH donors form 3:1 complexes with NO3, with HO distances of 1.85 0.5 . Thus, the optimal cavity radius for a tridentate host, defined as the

  7. Support Structure Design of the $$\\hbox{Nb}_{3}\\hbox{Sn}$$ Quadrupole for the High Luminosity LHC

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

    Juchno, M.; Ambrosio, G.; Anerella, M.; Cheng, D.; Felice, H.; Ferracin, P.; Perez, J. C.; Prin, H.; Schmalzle, J.

    2014-10-31

    New low-β quadrupole magnets are being developed within the scope of the High Luminosity LHC (HL-LHC) project in collaboration with the US LARP program. The aim of the HLLHC project is to study and implement machine upgrades necessary for increasing the luminosity of the LHC. The new quadrupoles, which are based on the Nb₃Sn superconducting technology, will be installed in the LHC Interaction Regions and will have to generate a gradient of 140 T/m in a coil aperture of 150 mm. In this paper, we describe the design of the short model magnet support structure and discuss results of themore » detailed 3D numerical analysis performed in preparation for the first short model test.« less

  8. Structure-Based Design of Potent and Selective 3-Phosphoinositide-Dependent Kinase-1 (PDK1) Inhibitors

    SciTech Connect (OSTI)

    Medina, Jesus R.; Becker, Christopher J.; Blackledge, Charles W.; Duquenne, Celine; Feng, Yanhong; Grant, Seth W.; Heerding, Dirk; Li, William H.; Miller, William H.; Romeril, Stuart P.; Scherzer, Daryl; Shu, Arthur; Bobko, Mark A.; Chadderton, Antony R.; Dumble, Melissa; Gardiner, Christine M.; Gilbert, Seth; Liu, Qi; Rabindran, Sridhar K.; Sudakin, Valery; Xiang, Hong; Brady, Pat G.; Campobasso, Nino; Ward, Paris; Axten, Jeffrey M.

    2014-10-02

    Phosphoinositide-dependent protein kinase-1(PDK1) is a master regulator of the AGC family of kinases and an integral component of the PI3K/AKT/mTOR pathway. As this pathway is among the most commonly deregulated across all cancers, a selective inhibitor of PDK1 might have utility as an anticancer agent. Herein we describe our lead optimization of compound 1 toward highly potent and selective PDK1 inhibitors via a structure-based design strategy. The most potent and selective inhibitors demonstrated submicromolar activity as measured by inhibition of phosphorylation of PDK1 substrates as well as antiproliferative activity against a subset of AML cell lines. In addition, reduction of phosphorylation of PDK1 substrates was demonstrated in vivo in mice bearing OCl-AML2 xenografts. These observations demonstrate the utility of these molecules as tools to further delineate the biology of PDK1 and the potential pharmacological uses of a PDK1 inhibitor.

  9. Identification and design of novel polymer-based mechanical transducers: A nano-structural model for thin film indentation

    SciTech Connect (OSTI)

    Villanueva, Joshua; Huang, Qian; Sirbuly, Donald J.

    2014-09-14

    Mechanical characterization is important for understanding small-scale systems and developing devices, particularly at the interface of biology, medicine, and nanotechnology. Yet, monitoring sub-surface forces is challenging with current technologies like atomic force microscopes (AFMs) or optical tweezers due to their probe sizes and sophisticated feedback mechanisms. An alternative transducer design relying on the indentation mechanics of a compressible thin polymer would be an ideal system for more compact and versatile probes, facilitating measurements in situ or in vivo. However, application-specific tuning of a polymer's mechanical properties can be burdensome via experimental optimization. Therefore, efficient transducer design requires a fundamental understanding of how synthetic parameters such as the molecular weight and grafting density influence the bulk material properties that determine the force response. In this work, we apply molecular-level polymer scaling laws to a first order elastic foundation model, relating the conformational state of individual polymer chains to the macroscopic compression of thin film systems. A parameter sweep analysis was conducted to observe predicted model trends under various system conditions and to understand how nano-structural elements influence the material stiffness. We validate the model by comparing predicted force profiles to experimental AFM curves for a real polymer system and show that it has reasonable predictive power for initial estimates of the force response, displaying excellent agreement with experimental force curves. We also present an analysis of the force sensitivity of an example transducer system to demonstrate identification of synthetic protocols based on desired mechanical properties. These results highlight the usefulness of this simple model as an aid for the design of a new class of compact and tunable nanomechanical force transducers.

  10. Structure-Based Design of Robust Glucose Biosensors using a Thermotoga maritima Periplasmic Glucose-Binding Protein

    SciTech Connect (OSTI)

    Tian,Y.; Cunco, M.; Changela, A.; Hocker, B.; Beese, L.; Hellinga, H.

    2007-01-01

    We report the design and engineering of a robust, reagentless fluorescent glucose biosensor based on the periplasmic glucose-binding protein obtained from Thermotoga maritima (tmGBP). The gene for this protein was cloned from genomic DNA and overexpressed in Escherichia coli, the identity of its cognate sugar was confirmed, ligand binding was studied, and the structure of its glucose complex was solved to 1.7 Angstroms resolution by X-ray crystallography. TmGBP is specific for glucose and exhibits high thermostability (midpoint of thermal denaturation is 119 {+-} 1 C and 144 {+-} 2 C in the absence and presence of 1 mM glucose, respectively). A series of fluorescent conjugates was constructed by coupling single, environmentally sensitive fluorophores to unique cysteines introduced by site-specific mutagenesis at positions predicted to be responsive to ligand-induced conformational changes based on the structure. These conjugates were screened to identify engineered tmGBPs that function as reagentless fluorescent glucose biosensors. The Y13C Cy5 conjugate is bright, gives a large response to glucose over concentration ranges appropriate for in vivo monitoring of blood glucose levels (1-30 mM), and can be immobilized in an orientation-specific manner in microtiter plates to give a reversible response to glucose. The immobilized protein retains its response after long-term storage at room temperature.

  11. Compiler-Directed File Layout Optimization for Hierarchical Storage Systems

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

    Ding, Wei; Zhang, Yuanrui; Kandemir, Mahmut; Son, Seung Woo

    2013-01-01

    File layout of array data is a critical factor that effects the behavior of storage caches, and has so far taken not much attention in the context of hierarchical storage systems. The main contribution of this paper is a compiler-driven file layout optimization scheme for hierarchical storage caches. This approach, fully automated within an optimizing compiler, analyzes a multi-threaded application code and determines a file layout for each disk-resident array referenced by the code, such that the performance of the target storage cache hierarchy is maximized. We tested our approach using 16 I/O intensive application programs and compared its performancemore » against two previously proposed approaches under different cache space management schemes. Our experimental results show that the proposed approach improves the execution time of these parallel applications by 23.7% on average.« less

  12. Sandia National Labs: PCNSC: Research: Collective Hierarchical Systems

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

    Collective Hierarchical Systems: Developing life-emulating technologies by exploiting the physics of far-from-equilibrium, self-assembling systems What is it? We want to establish the Physical, Chemical and Nano Sciences Center and Sandia National Laboratories as major players in developing the interdisciplinary science of complex, far-from-equilibrium, self-assembling systems. These are systems that self-assemble highly organized states dynamically, across multiple length scales, through the

  13. Extended ensemble Kalman filters for data assimilation in hierarchical

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

    state-space models | Argonne Leadership Computing Facility Extended ensemble Kalman filters for data assimilation in hierarchical state-space models Event Sponsor: Mathematics and Computer Science Division LANS Seminar Start Date: Jul 29 2016 - 10:30am Building/Room: Building 240/Room 1404-1405 Location: Argonne National Laboratory Speaker(s): Matthias Katzfuss Speaker(s) Title: Texas A&M University Host: Emil Constantinescu Event Website:

  14. Hierarchical Diagnosis M. Allmen and W. P. Kegelmeyer, Jr.

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

    M. Allmen and W. P. Kegelmeyer, Jr. Sandia National laboratories Livermore, CA 94551 Three-dimensional (3-D) cloud characterization permits the derivation of important cloud geometry properties such as fractional cloudiness, mean cloud and clear length, aspect ratio, and the morphology of cloud cover. These properties are needed as input to the hierarchical diagnosis (HD) and instantaneous radiative transfer (IRF) models, to validate sub-models for cloud occurrence and formation, and to Central

  15. Hierarchically Ordered Porous Carbon Films for Commercial Water

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

    Desalination - Energy Innovation Portal Industrial Technologies Industrial Technologies Hydropower, Wave and Tidal Hydropower, Wave and Tidal Advanced Materials Advanced Materials Find More Like This Return to Search Hierarchically Ordered Porous Carbon Films for Commercial Water Desalination Oak Ridge National Laboratory Contact ORNL About This Technology Publications: PDF Document Publication 11-G00230_ID2431 (2).pdf (777 KB) Technology Marketing SummaryPorous carbon films that can be

  16. Constructing hierarchical interfaces: TiO2-supported PtFe-FeOx nanowires for room temperature CO oxidation

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

    Zhu, Huiyuan; Wu, Zili; Dong, Su; Veith, Gabriel M.; Lu, Hanfeng; Zhang, Pengfei; Chai, Song -Hai; Dai, Sheng

    2015-08-05

    This is a report of a facile approach to constructing catalytic active hierarchical interfaces in one-dimensional (1D) nanostructure, exemplified by the synthesis of TiO2-supported PtFe–FeOx nanowires (NWs). The hierarchical interface, constituting atomic level interactions between PtFe and FeOx within each NW and the interactions between NWs and support (TiO2), enables CO oxidation with 100% conversion at room temperature. We identify the role of the two interfaces by probing the CO oxidation reaction with isotopic labeling experiments. Both the oxygen atoms (Os) in FeOx and TiO2 participate in the initial CO oxidation, facilitating the reaction through a redox pathway. Moreover, themore » intact 1D structure leads to the high stability of the catalyst. After 30 h in the reaction stream, the PtFe–FeOx/TiO2 catalyst exhibits no activity decay. These results provide a general approach and new insights into the construction of hierarchical interfaces for advanced catalysis.« less

  17. Distributed Hierarchical Control Architecture for Transient Dynamics Improvement in Power Systems

    SciTech Connect (OSTI)

    Marinovici, Laurentiu D.; Lian, Jianming; Kalsi, Karanjit; Du, Pengwei; Elizondo, Marcelo A.

    2013-08-24

    In this paper, a novel distributed hierarchical coordinated control architecture is proposed for large scale power systems. The newly considered architecture facilitates frequency restoration and power balancing functions to be decoupled and implemented at different levels. At the local level, decentralized robust generator controllers are designed to quickly restore frequency after large faults and disturbances in the system. The controllers presented herein are shown to improve transient stability performance, as compared to conventional governor and excitation control. At the area level, Automatic Generation Control (AGC) is modified and coordinates with the decentralized robust controllers to reach the interchange schedule in the tie lines. The interaction of local and zonal controllers is validated through detailed simulations.

  18. HIERARCHICAL METHODOLOGY FOR MODELING HYDROGEN STORAGE SYSTEMS PART II: DETAILED MODELS

    SciTech Connect (OSTI)

    Hardy, B; Donald L. Anton, D

    2008-12-22

    There is significant interest in hydrogen storage systems that employ a media which either adsorbs, absorbs or reacts with hydrogen in a nearly reversible manner. In any media based storage system the rate of hydrogen uptake and the system capacity is governed by a number of complex, coupled physical processes. To design and evaluate such storage systems, a comprehensive methodology was developed, consisting of a hierarchical sequence of models that range from scoping calculations to numerical models that couple reaction kinetics with heat and mass transfer for both the hydrogen charging and discharging phases. The scoping models were presented in Part I [1] of this two part series of papers. This paper describes a detailed numerical model that integrates the phenomena occurring when hydrogen is charged and discharged. A specific application of the methodology is made to a system using NaAlH{sub 4} as the storage media.

  19. Time Synchronization in Hierarchical TESLA Wireless Sensor Networks

    SciTech Connect (OSTI)

    Jason L. Wright; Milos Manic

    2009-08-01

    Time synchronization and event time correlation are important in wireless sensor networks. In particular, time is used to create a sequence events or time line to answer questions of cause and effect. Time is also used as a basis for determining the freshness of received packets and the validity of cryptographic certificates. This paper presents secure method of time synchronization and event time correlation for TESLA-based hierarchical wireless sensor networks. The method demonstrates that events in a TESLA network can be accurately timestamped by adding only a few pieces of data to the existing protocol.

  20. A prototype functional language implementation for hierarchical- memory architectures

    SciTech Connect (OSTI)

    Wolski, R.; Feo, J.; Cann, D.

    1992-01-14

    Programming languages are the most important tool at a programmers' disposal. All other tools correct, visualize, or evaluate the product crafted by this tool. The advent of multiprocessor computer systems has greatly complicated the programmer's task an increased his need for high-level languages capable of automatically taming these architectures. In this paper, we describe a prototype implementation of Sisal for multiprocessor, hierarchical-memory systems. The implementation includes explicit compiler and runtime control that effectively exploits the different levels of memory and manages interprocess communications (IPC). We give preliminary performance results for this system on the BBN TC2000.

  1. A Hierarchical Security Architecture for Cyber-Physical Systems

    SciTech Connect (OSTI)

    Quanyan Zhu; Tamer Basar

    2011-08-01

    Security of control systems is becoming a pivotal concern in critical national infrastructures such as the power grid and nuclear plants. In this paper, we adopt a hierarchical viewpoint to these security issues, addressing security concerns at each level and emphasizing a holistic cross-layer philosophy for developing security solutions. We propose a bottom-up framework that establishes a model from the physical and control levels to the supervisory level, incorporating concerns from network and communication levels. We show that the game-theoretical approach can yield cross-layer security strategy solutions to the cyber-physical systems.

  2. Vehicle Technologies Office Merit Review 2014: Coupled Hierarchical Models for Thermal, Mechanical, Electrical and Electrochemical Processes

    Office of Energy Efficiency and Renewable Energy (EERE)

    Presentation given by [company name] at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about coupled hierarchical models...

  3. Three-dimensional structures of Plasmodium falciparum spermidine synthase with bound inhibitors suggest new strategies for drug design

    SciTech Connect (OSTI)

    Sprenger, Janina; Svensson, Bo; Hlander, Jenny; Carey, Jannette; Persson, Lo; Al-Karadaghi, Salam

    2015-03-01

    In this work, X-ray crystallography was used to examine ligand complexes of spermidine synthase from the malaria parasite Plasmodium falciparum (PfSpdS). The enzymes of the polyamine-biosynthesis pathway have been proposed to be promising drug targets in the treatment of malaria. Spermidine synthase (SpdS; putrescine aminopropyltransferase) catalyzes the transfer of the aminopropyl moiety from decarboxylated S-adenosylmethionine to putrescine, leading to the formation of spermidine and 5?-methylthioadenosine (MTA). In this work, X-ray crystallography was used to examine ligand complexes of SpdS from the malaria parasite Plasmodium falciparum (PfSpdS). Five crystal structures were determined of PfSpdS in complex with MTA and the substrate putrescine, with MTA and spermidine, which was obtained as a result of the enzymatic reaction taking place within the crystals, with dcAdoMet and the inhibitor 4-methylaniline, with MTA and 4-aminomethylaniline, and with a compound predicted in earlier in silico screening to bind to the active site of the enzyme, benzimidazol-(2-yl)pentan-1-amine (BIPA). In contrast to the other inhibitors tested, the complex with BIPA was obtained without any ligand bound to the dcAdoMet-binding site of the enzyme. The complexes with the aniline compounds and BIPA revealed a new mode of ligand binding to PfSpdS. The observed binding mode of the ligands, and the interplay between the two substrate-binding sites and the flexible gatekeeper loop, can be used in the design of new approaches in the search for new inhibitors of SpdS.

  4. Exploiting Photo-induced Reactions in Polymer Blends to Create Hierarchically Ordered, Defect-free Materials

    ScienceCinema (OSTI)

    Balazs, Anna [University of Pittsburgh, Pittsburgh, Pennsylvania, United States

    2010-01-08

    Computer simulations reveal how photo-induced chemical reactions can be exploited to create long-range order in binary and ternary polymeric materials. The process is initiated by shining a spatially uniform light over a photosensitive AB binary blend, which undergoes both a reversible chemical reaction and phase separation. We then introduce a well-collimated, higher-intensity light source. Rastering this secondary light over the sample locally increases the reaction rate and causes formation of defect-free, spatially periodic structures. These binary structures resemble either the lamellar or hexagonal phases of microphase-separated di-block copolymers. We measure the regularity of the ordered structures as a function of the relative reaction rates for different values of the rastering speed and determine the optimal conditions for creating defect-free structures in the binary systems. We then add a non-reactive homo-polymer C, which is immiscible with both A and B. We show that this component migrates to regions that are illuminated by the secondary, higher-intensity light, allowing us to effectively write a pattern of C onto the AB film. Rastering over the ternary blend with this collimated light now leads to hierarchically ordered patterns of A, B, and C. The findings point to a facile, non-intrusive process for manufacturing high-quality polymeric devices in a low-cost, efficient manner.

  5. Hierarchical Marginal Land Assessment for Land Use Planning

    SciTech Connect (OSTI)

    Kang, Shujiang; Post, Wilfred M; Wang, Dali; Nichols, Dr Jeff A; Bandaru, Vara Prasad

    2013-01-01

    Marginal land provides an alternative potential for food and bioenergy production in the face of limited land resources; however, effective assessment of marginal lands is not well addressed. Concerns over environmental risks, ecosystem services and sustainability for marginal land have been widely raised. The objective of this study was to develop a hierarchical marginal land assessment framework for land use planning and management. We first identified major land functions linking production, environment, ecosystem services and economics, and then classified land resources into four categories of marginal land using suitability and limitations associated with major management goals, including physically marginal land, biologically marginal land, environmental-ecological marginal land, and economically marginal land. We tested this assessment framework in south-western Michigan, USA. Our results indicated that this marginal land assessment framework can be potentially feasible on land use planning for food and bioenergy production, and balancing multiple goals of land use management. We also compared our results with marginal land assessment from the Conservation Reserve Program (CRP) and land capability classes (LCC) that are used in the US. The hierarchical assessment framework has advantages of quantitatively reflecting land functions and multiple concerns. This provides a foundation upon which focused studies can be identified in order to improve the assessment framework by quantifying high-resolution land functions associated with environment and ecosystem services as well as their criteria are needed to improve the assessment framework.

  6. Quadratic partial eigenvalue assignment in large-scale stochastic dynamic systems for resilient and economic design

    SciTech Connect (OSTI)

    Das, Sonjoy; Goswami, Kundan; Datta, Biswa N.

    2014-12-10

    Failure of structural systems under dynamic loading can be prevented via active vibration control which shifts the damped natural frequencies of the systems away from the dominant range of loading spectrum. The damped natural frequencies and the dynamic load typically show significant variations in practice. A computationally efficient methodology based on quadratic partial eigenvalue assignment technique and optimization under uncertainty has been formulated in the present work that will rigorously account for these variations and result in an economic and resilient design of structures. A novel scheme based on hierarchical clustering and importance sampling is also developed in this work for accurate and efficient estimation of probability of failure to guarantee the desired resilience level of the designed system. Numerical examples are presented to illustrate the proposed methodology.

  7. Structure tracking aided design and synthesis of Li3V2(PO4)3 nanocrystals as high-power cathodes for lithium ion batteries

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

    Wang, Liping; Bai, Jianming; Gao, Peng; Wang, Xiaoya; Looney, J. Patrick; Wang, Feng

    2015-07-30

    In this study, preparing new electrode materials with synthetic control of phases and electrochemical properties is desirable for battery applications but hardly achievable without knowing how the synthesis reaction proceeds. Herein, we report on structure tracking-aided design and synthesis of single-crystalline Li3V2(PO4)3 (LVP) nanoparticles with extremely high rate capability. A comprehensive investigation was made to the local structural orderings of the involved phases and their evolution toward forming LVP phase using in situ/ex situ synchrotron X-ray and electron-beam diffraction, spectroscopy, and imaging techniques. The results shed light on the thermodynamics and kinetics of synthesis reactions and enabled the design ofmore » a cost-efficient synthesis protocol to make nanocrystalline LVP, wherein solvothermal treatment is a crucial step leading to an amorphous intermediate with local structural ordering resembling that of LVP, which, upon calcination at moderate temperatures, rapidly transforms into the desired LVP phase. The obtained LVP particles are about 50 nm, coated with a thin layer of amorphous carbon and featured with excellent cycling stability and rate capability – 95% capacity retention after 200 cycles and 66% theoretical capacity even at a current rate of 10 C. The structure tracking based method we developed in this work offers a new way of designing battery electrodes with synthetic control of material phases and properties.« less

  8. Compiling software for a hierarchical distributed processing system

    SciTech Connect (OSTI)

    Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

    2013-12-31

    Compiling software for a hierarchical distributed processing system including providing to one or more compiling nodes software to be compiled, wherein at least a portion of the software to be compiled is to be executed by one or more nodes; compiling, by the compiling node, the software; maintaining, by the compiling node, any compiled software to be executed on the compiling node; selecting, by the compiling node, one or more nodes in a next tier of the hierarchy of the distributed processing system in dependence upon whether any compiled software is for the selected node or the selected node's descendents; sending to the selected node only the compiled software to be executed by the selected node or selected node's descendent.

  9. UNSUPERVISED TRANSIENT LIGHT CURVE ANALYSIS VIA HIERARCHICAL BAYESIAN INFERENCE

    SciTech Connect (OSTI)

    Sanders, N. E.; Soderberg, A. M.; Betancourt, M.

    2015-02-10

    Historically, light curve studies of supernovae (SNe) and other transient classes have focused on individual objects with copious and high signal-to-noise observations. In the nascent era of wide field transient searches, objects with detailed observations are decreasing as a fraction of the overall known SN population, and this strategy sacrifices the majority of the information contained in the data about the underlying population of transients. A population level modeling approach, simultaneously fitting all available observations of objects in a transient sub-class of interest, fully mines the data to infer the properties of the population and avoids certain systematic biases. We present a novel hierarchical Bayesian statistical model for population level modeling of transient light curves, and discuss its implementation using an efficient Hamiltonian Monte Carlo technique. As a test case, we apply this model to the Type IIP SN sample from the Pan-STARRS1 Medium Deep Survey, consisting of 18,837 photometric observations of 76 SNe, corresponding to a joint posterior distribution with 9176 parameters under our model. Our hierarchical model fits provide improved constraints on light curve parameters relevant to the physical properties of their progenitor stars relative to modeling individual light curves alone. Moreover, we directly evaluate the probability for occurrence rates of unseen light curve characteristics from the model hyperparameters, addressing observational biases in survey methodology. We view this modeling framework as an unsupervised machine learning technique with the ability to maximize scientific returns from data to be collected by future wide field transient searches like LSST.

  10. Application of structural-mechanics methods to the design of large tandem-mirror fusion devices (MFTF-B). Revision 1

    SciTech Connect (OSTI)

    Karpenko, V.N.; Ng, D.S.

    1985-08-15

    The Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory requires state-of-the-art structural-mechanics methods to deal with access constraints for plasma heating and diagnostics, alignment requirements, and load complexity and variety. Large interactive structures required an integrated analytical approach to achieve a reasonable level of overall system optimization. The Tandem Magnet Generator (TMG) creates a magnet configuration for the EFFI calculation of electromagnetic-field forces that, coupled with other loads, form the input loading to magnet and vessel finite-element models. The analytical results provide the data base for detailed design of magnet, vessel, foundation, and interaction effects. 13 refs.

  11. Design of HIV-1 Protease Inhibitors with C3-Substituted Hexahydrocyclopentafuranyl Urethanes as P2-Ligands: Synthesis, Biological Evaluation, and Protein-Ligand X-ray Crystal Structure

    SciTech Connect (OSTI)

    Ghosh, Arun K; Chapsal, Bruno D; Parham, Garth L; Steffey, Melinda; Agniswamy, Johnson; Wang, Yuan-Fang; Amano, Masayuki; Weber, Irene T; Mitsuya, Hiroaki

    2011-11-07

    We report the design, synthesis, biological evaluation, and the X-ray crystal structure of a novel inhibitor bound to the HIV-1 protease. Various C3-functionalized cyclopentanyltetrahydrofurans (Cp-THF) were designed to interact with the flap Gly48 carbonyl or amide NH in the S2-subsite of the HIV-1 protease. We investigated the potential of those functionalized ligands in combination with hydroxyethylsulfonamide isosteres. Inhibitor 26 containing a 3-(R)-hydroxyl group on the Cp-THF core displayed the most potent enzyme inhibitory and antiviral activity. Our studies revealed a preference for the 3-(R)-configuration over the corresponding 3-(S)-derivative. Inhibitor 26 exhibited potent activity against a panel of multidrug-resistant HIV-1 variants. A high resolution X-ray structure of 26-bound HIV-1 protease revealed important molecular insight into the ligand-binding site interactions.

  12. Surface engineering of hierarchical platinum-cobalt nanowires for efficient electrocatalysis

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

    Bu, Lingzheng; Guo, Shaojun; Zhang, Xu; Shen, Xuan; Su, Dong; Lu, Gang; Zhu, Xing; Yao, Jianlin; Guo, Jun; Huang, Xiaoqing

    2016-06-29

    Despite intense research in past decades, the lack of high-performance catalysts for fuel cell reactions remains a challenge in realizing fuel cell technologies for transportation applications. Here we report a facile strategy for synthesizing hierarchical platinum-cobalt nanowires with high-index, platinum-rich facets and ordered intermetallic structure. These structural features enable unprecedented performance for the oxygen reduction and alcohol oxidation reactions. The specific/mass activities of the platinum-cobalt nanowires for oxygen reduction reaction are 39.6/33.7 times higher than commercial Pt/C catalyst, respectively. Density functional theory simulations reveal that the active threefold hollow sites on the platinum-rich high-index facets provide an additional factor inmore » enhancing oxygen reduction reaction activities. The nanowires are stable in the electrochemical conditions and also thermally stable. Furthermore, this work may represent a key step towards scalable production of high performance platinum-based nanowires for applications in catalysis and energy conversion.« less

  13. Towards intelligent microstructural design of Nanocomposite Materials. Lightweight, high strength structural/armor materials for service in extreme environments

    SciTech Connect (OSTI)

    Mara, Nathan Allan; Bronkhorst, Curt Allan; Beyerlein, Irene Jane

    2015-12-21

    The intent of this research effort is to prove the hypothesis that: Through the employment of controlled processing parameters which are based upon integrated advanced material characterization and multi-physics material modeling, bulk nanolayered composites can be designed to contain high densities of preferred interfaces that can serve as supersinks for the defects responsible for premature damage and failure.

  14. THE EVOLUTION OF BRIGHTEST CLUSTER GALAXIES IN A HIERARCHICAL UNIVERSE

    SciTech Connect (OSTI)

    Tonini, Chiara; Bernyk, Maksym; Croton, Darren [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Melbourne, VIC 3122 (Australia); Maraston, Claudia; Thomas, Daniel [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 3FX (United Kingdom)

    2012-11-01

    We investigate the evolution of brightest cluster galaxies (BCGs) from redshift z {approx} 1.6 to z = 0. We upgrade the hierarchical semi-analytic model of Croton et al. with a new spectro-photometric model that produces realistic galaxy spectra, making use of the Maraston stellar populations and a new recipe for the dust extinction. We compare the model predictions of the K-band luminosity evolution and the J - K, V - I, and I - K color evolution with a series of data sets, including those of Collins et al. who argued that semi-analytic models based on the Millennium simulation cannot reproduce the red colors and high luminosity of BCGs at z > 1. We show instead that the model is well in range of the observed luminosity and correctly reproduces the color evolution of BCGs in the whole redshift range up to z {approx} 1.6. We argue that the success of the semi-analytic model is in large part due to the implementation of a more sophisticated spectro-photometric model. An analysis of the model BCGs shows an increase in mass by a factor of 2-3 since z {approx} 1, and star formation activity down to low redshifts. While the consensus regarding BCGs is that they are passively evolving, we argue that this conclusion is affected by the degeneracy between star formation history and stellar population models used in spectral energy distribution fitting, and by the inefficacy of toy models of passive evolution to capture the complexity of real galaxies, especially those with rich merger histories like BCGs. Following this argument, we also show that in the semi-analytic model the BCGs show a realistic mix of stellar populations, and that these stellar populations are mostly old. In addition, the age-redshift relation of the model BCGs follows that of the universe, meaning that given their merger history and star formation history, the ageing of BCGs is always dominated by the ageing of their stellar populations. In a {Lambda}CDM universe, we define such evolution as 'passive

  15. A Hierarchical Framework for Demand-Side Frequency Control

    SciTech Connect (OSTI)

    Moya, Christian; Zhang, Wei; Lian, Jianming; Kalsi, Karanjit

    2014-06-02

    With large-scale plans to integrate renewable generation, more resources will be needed to compensate for the uncertainty associated with intermittent generation resources. Under such conditions, performing frequency control using only supply-side resources become not only prohibitively expensive but also technically difficult. It is therefore important to explore how a sufficient proportion of the loads could assume a routine role in frequency control to maintain the stability of the system at an acceptable cost. In this paper, a novel hierarchical decentralized framework for frequency based load control is proposed. The framework involves two decision layers. The top decision layer determines the optimal droop gain required from the aggregated load response on each bus using a robust decentralized control approach. The second layer consists of a large number of devices, which switch probabilistically during contingencies so that the aggregated power change matches the desired droop amount according to the updated gains. The proposed framework is based on the classical nonlinear multi-machine power system model, and can deal with timevarying system operating conditions while respecting the physical constraints of individual devices. Realistic simulation results based on a 68-bus system are provided to demonstrate the effectiveness of the proposed strategy.

  16. A novel biomimetic approach to the design of high-performance ceramic/metal composites

    SciTech Connect (OSTI)

    Launey, Maximilien E.; Munch, Etienne; Alsem, Daan Hein; Saiz, Eduardo; Tomsia, Antoni P.; Ritchie, Robert O.

    2009-08-01

    The prospect of extending natural biological design to develop new synthetic ceramic-metal composite materials is examined. Using ice-templating of ceramic suspensions and subsequent metal infiltration, we demonstrate that the concept of ordered hierarchical design can be applied to create fine-scale laminated ceramic-metal (bulk) composites that are inexpensive, lightweight and display exceptional damage-tolerance properties. Specifically, Al{sub 2}O{sub 3}/Al-Si laminates with ceramic contents up to approximately 40 vol% and with lamellae thicknesses down to 10 {micro}m were processed and characterized. These structures achieve an excellent fracture toughness of 40 MPa{radical}m at a tensile strength of approximately 300 MPa. Salient toughening mechanisms are described together with further toughening strategies.

  17. PEDOT-PSS coated ZnO/C hierarchical porous nanorods as ultralong...

    Office of Scientific and Technical Information (OSTI)

    PEDOT-PSS coated ZnOC hierarchical porous nanorods as ultralong-life anode material for lithium ion batteries This content will become publicly available on November 16, 2017 ...

  18. Simultaneous hierarchical segmentation and vectorization of satellite images through combined data sampling and anisotropic triangulation

    SciTech Connect (OSTI)

    Grazzini, Jacopo; Prasad, Lakshman; Dillard, Scott

    2010-10-21

    The automatic detection, recognition , and segmentation of object classes in remote sensed images is of crucial importance for scene interpretation and understanding. However, it is a difficult task because of the high variability of satellite data. Indeed, the observed scenes usually exhibit a high degree of complexity, where complexity refers to the large variety of pictorial representations of objects with the same semantic meaning and also to the extensive amount of available det.ails. Therefore, there is still a strong demand for robust techniques for automatic information extraction and interpretation of satellite images. In parallel, there is a growing interest in techniques that can extract vector features directly from such imagery. In this paper, we investigate the problem of automatic hierarchical segmentation and vectorization of multispectral satellite images. We propose a new algorithm composed of the following steps: (i) a non-uniform sampling scheme extracting most salient pixels in the image, (ii) an anisotropic triangulation constrained by the sampled pixels taking into account both strength and directionality of local structures present in the image, (iii) a polygonal grouping scheme merging, through techniques based on perceptual information , the obtained segments to a smaller quantity of superior vectorial objects. Besides its computational efficiency, this approach provides a meaningful polygonal representation for subsequent image analysis and/or interpretation.

  19. Satellite dwarf galaxies in a hierarchical universe: the prevalence of dwarf-dwarf major mergers

    SciTech Connect (OSTI)

    Deason, Alis; Wetzel, Andrew; Garrison-Kimmel, Shea

    2014-10-20

    Mergers are a common phenomenon in hierarchical structure formation, especially for massive galaxies and clusters, but their importance for dwarf galaxies in the Local Group remains poorly understood. We investigate the frequency of major mergers between dwarf galaxies in the Local Group using the ELVIS suite of cosmological zoom-in dissipationless simulations of Milky Way- and M31-like host halos. We find that ?10% of satellite dwarf galaxies with M {sub star} > 10{sup 6} M {sub ?} that are within the host virial radius experienced a major merger of stellar mass ratio closer than 0.1 since z = 1, with a lower fraction for lower mass dwarf galaxies. Recent merger remnants are biased toward larger radial distance and more recent virial infall times, because most recent mergers occurred shortly before crossing within the virial radius of the host halo. Satellite-satellite mergers also occur within the host halo after virial infall, catalyzed by the large fraction of dwarf galaxies that fell in as part of a group. The merger fraction doubles for dwarf galaxies outside of the host virial radius, so the most distant dwarf galaxies in the Local Group are the most likely to have experienced a recent major merger. We discuss the implications of these results on observable dwarf merger remnants, their star formation histories, the gas content of mergers, and massive black holes in dwarf galaxies.

  20. Regulatory Safety Issues in the Structural Design Criteria of ASME Section III Subsection NH and for Very High Temperatures for VHTR & GEN IV

    SciTech Connect (OSTI)

    William J. O’Donnell; Donald S. Griffin

    2007-05-07

    The objective of this task is to identify issues relevant to ASME Section III, Subsection NH [1], and related Code Cases that must be resolved for licensing purposes for VHTGRs (Very High Temperature Gas Reactor concepts such as those of PBMR, Areva, and GA); and to identify the material models, design criteria, and analysis methods that need to be added to the ASME Code to cover the unresolved safety issues. Subsection NH was originally developed to provide structural design criteria and limits for elevated-temperature design of Liquid Metal Fast Breeder Reactor (LMFBR) systems and some gas-cooled systems. The U.S. Nuclear Regulatory Commission (NRC) and its Advisory Committee for Reactor Safeguards (ACRS) reviewed the design limits and procedures in the process of reviewing the Clinch River Breeder Reactor (CRBR) for a construction permit in the late 1970s and early 1980s, and identified issues that needed resolution. In the years since then, the NRC and various contractors have evaluated the applicability of the ASME Code and Code Cases to high-temperature reactor designs such as the VHTGRs, and identified issues that need to be resolved to provide a regulatory basis for licensing. This Report describes: (1) NRC and ACRS safety concerns raised during the licensing process of CRBR , (2) how some of these issues are addressed by the current Subsection NH of the ASME Code; and (3) the material models, design criteria, and analysis methods that need to be added to the ASME Code and Code Cases to cover unresolved regulatory issues for very high temperature service.

  1. Conceptual Design Report Cask Loadout Sys and Cask Drop Redesign for the Immersion Pail Support Structure and Operator Interface Platform at 105 K West

    SciTech Connect (OSTI)

    LANGEVIN, A.S.

    1999-07-12

    This conceptual design report documents the redesign of the IPSS and the OIP in the 105 KW Basin south loadout pit due to a postulated cask drop accident, as part of Project A.5/A.6, Canister Transfer Facility Modifications. Project A.5/A.6 involves facility modifications needed to transfer fuel from the basin into the cask-MCO. The function of the IPSS is to suspend, guide, and position the immersion pail. The immersion pail protects the cask-MCO from contamination by basin water and acts as a lifting device for the cask-MCO. The OIP provides operator access to the south loadout pit. Previous analyses studied the effects of a cask-MCO drop on the south loadout pit concrete structure and on the IPSS. The most recent analysis considered the resulting loads at the pit slab/wall joint (Kanjilal, 1999). This area had not been modeled previously, and the analysis results indicate that the demand capacity exceeds the allowable at the slab/wall joint. The energy induced on the south loadout pit must be limited such that the safety class function of the basin is maintained. The solution presented in this CDR redesigns the IPSS and the OIP to include impact-absorbing features that will reduce the induced energy. The impact absorbing features of the new design include: Impact-absorbing material at the IPSS base and at the upper portion of the IPSS legs. A sleeve which provides a hydraulic means of absorbing energy. Designing the OIP to act as an impact absorber. The existing IPSS structure in 105 KW will be removed. This conceptual design considers only loads resulting from drops directly over the IPSS and south loadout pit area. Drops in other areas of the basin are not considered, and will be covered as part of a future revision to this CDR.

  2. Computer Aided Multi-scale Design of SiC-Si3N4 Nanoceramic Composites for High-Temperature Structural Applications

    SciTech Connect (OSTI)

    Vikas Tomer; John Renaud

    2010-08-31

    It is estimated that by using better and improved high temperature structural materials, the power generation efficiency of the power plants can be increased by 15% resulting in significant cost savings. One such promising material system for future high-temperature structural applications in power plants is Silicon Carbide-Silicon Nitride (SiC-Si{sub 3}N{sub 4}) nanoceramic matrix composites. The described research work focuses on multiscale simulation-based design of these SiC-Si{sub 3}N{sub 4} nanoceramic matrix composites. There were two primary objectives of the research: (1) Development of a multiscale simulation tool and corresponding multiscale analyses of the high-temperature creep and fracture resistance properties of the SiC-Si{sub 3}N{sub 4} nanocomposites at nano-, meso- and continuum length- and timescales; and (2) Development of a simulation-based robust design optimization methodology for application to the multiscale simulations to predict the range of the most suitable phase morphologies for the desired high-temperature properties of the SiC-Si{sub 3}N{sub 4} nanocomposites. The multiscale simulation tool is based on a combination of molecular dynamics (MD), cohesive finite element method (CFEM), and continuum level modeling for characterizing time-dependent material deformation behavior. The material simulation tool is incorporated in a variable fidelity model management based design optimization framework. Material modeling includes development of an experimental verification framework. Using material models based on multiscaling, it was found using molecular simulations that clustering of the SiC particles near Si{sub 3}N{sub 4} grain boundaries leads to significant nanocomposite strengthening and significant rise in fracture resistance. It was found that a control of grain boundary thicknesses by dispersing non-stoichiometric carbide or nitride phases can lead to reduction in strength however significant rise in fracture strength. The

  3. Constructing hierarchical interfaces: TiO2-supported PtFe-FeOx nanowires for room temperature CO oxidation

    SciTech Connect (OSTI)

    Zhu, Huiyuan; Wu, Zili; Dong, Su; Veith, Gabriel M.; Lu, Hanfeng; Zhang, Pengfei; Chai, Song -Hai; Dai, Sheng

    2015-08-05

    This is a report of a facile approach to constructing catalytic active hierarchical interfaces in one-dimensional (1D) nanostructure, exemplified by the synthesis of TiO2-supported PtFe–FeOx nanowires (NWs). The hierarchical interface, constituting atomic level interactions between PtFe and FeOx within each NW and the interactions between NWs and support (TiO2), enables CO oxidation with 100% conversion at room temperature. We identify the role of the two interfaces by probing the CO oxidation reaction with isotopic labeling experiments. Both the oxygen atoms (Os) in FeOx and TiO2 participate in the initial CO oxidation, facilitating the reaction through a redox pathway. Moreover, the intact 1D structure leads to the high stability of the catalyst. After 30 h in the reaction stream, the PtFe–FeOx/TiO2 catalyst exhibits no activity decay. These results provide a general approach and new insights into the construction of hierarchical interfaces for advanced catalysis.

  4. Constructing hierarchical interfaces: TiO2-supported PtFe-FeOx nanowires for room temperature CO oxidation

    SciTech Connect (OSTI)

    Zhu, Huiyuan; Wu, Zili; Dong, Su; Veith, Gabriel M; Lu, Hanfeng; Zhang, Pengfei; Chai, Songhai; Dai, Sheng

    2015-08-05

    This is a report of a facile approach to constructing catalytic active hierarchical interfaces in one-dimensional (1D) nanostructure, exemplified by the synthesis of TiO2-supported PtFeFeOx nanowires (NWs). The hierarchical interface, constituting atomic level interactions between PtFe and FeOx within each NW and the interactions between NWs and support (TiO2), enables CO oxidation with 100% conversion at room temperature. We identify the role of the two interfaces by probing the CO oxidation reaction with isotopic labeling experiments. Both the oxygen atoms (Os) in FeOx and TiO2 participate in the initial CO oxidation, facilitating the reaction through a redox pathway. Moreover, the intact 1D structure leads to the high stability of the catalyst. After 30 h in the reaction stream, the PtFeFeOx/TiO2 catalyst exhibits no activity decay. These results provide a general approach and new insights into the construction of hierarchical interfaces for advanced catalysis.

  5. Fluid Interface Reactions, Structures and Transport

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

    Research Perspectives Nonlinear optical approaches for elucidating interfacial fluid and sorbed species structures and dynamics pdf Structural and Dynamic Properties of Room Temperature Ionic Liquids Confined within Hierarchical Porous Materials pdf Structure and Dynamics of Electrical Double Layer Using Integrated Scanning Probe Microscopy and Molecular Simulations pdf Effects of Nano-Confinement on the Fluid Interfacial Structure, Dynamics and Thermodynamic behavior pdf Molecular Insights into

  6. Structural Design and Analysis for a Double-Band Cold Mass Support of the MICE Coupling Magnet

    SciTech Connect (OSTI)

    Green, Michael A; Wu, Hong; Liu, X. K.; Wang, Li; Li, S. Y.; Guo, XingLong; Pan, Heng; Xu, FengYu

    2009-07-01

    The cooling channel of Muon Ionization Cooling Experiment (MICE) consists of eighteen superconducting solenoid coils, which are magnetically hooked together. A pair ofcoupling magnets operating at 4 K is applied to produce up to .6 T magnetic field on the magnet centerline to keep muon beam within the RF cavity windows. The peak magnetic force on the coupling magnet from other magnets in the MICE channel is up to 500 kN inlongitudinal direction, and the requirements for magnet center and axis azimuthal angle at 4 K are stringent. A self-centered double-band cold mass support system with intermediatethermal interruption is applied for the coupling magnet. The physical center of the magnet does not change as it is cooled down from 300 K to 4.2 K with this support system. In this paper the design parameters of the support system are discussed. The integral analysis of the support system using FEA method was carried out to etermine the tension forces in bands when various loads are applied. The magnet centre displacement and concentricity deviation form the axis of the warm bore are obtained, and the peak tension in support bands is also determined according to the simulation results.

  7. Molecular and crystal structures of p-heptyloxyphenyl p-hexyloxybenzoate and p-butyloxyphenyl p-heptyloxybenzoate: Mesophase design

    SciTech Connect (OSTI)

    Kuz'mina, L. G. Gunina, M. A.; Churakov, A. V.; Pestov, S. M.

    2013-03-15

    Two aromatic esters with the formulas C{sub 6}H{sub 13}-O-C{sub 6}H{sub 4}-C(O)O-C{sub 6}H{sub 4}-O-C{sub 7}H{sub 15} (1) and C{sub 7}H{sub 15}-O-C{sub 6}H{sub 4}-C(O)O-C{sub 6}H{sub 4}-O-C{sub 4}H{sub 9} (2) belonging to nematic liquid-crystal compounds were studied by X-ray diffraction. Compound 1 crystallizes in two modifications: monoclinic (1-m) and triclinic (1-tr). The crystal packing of 1 and 2 is built from alternating loosely packed aliphatic regions and closely packed aromatic regions. In crystal structures 1-m and 2, the aromatic regions are linked into chains by hydrogen bonds with the participation of the carbonyl oxygen atom of the ester group and the C-H fragment of the benzene ring, but these hydrogen bonds in 1-m are much weaker than in 2. In 1-m there are {pi}-stacking interactions between the molecules, resulting in the formation of centrosymmetric dimers with an interplanar distance of 3.45 A. In 1-tr, the aromatic fragments form a herringbone packing motif favorable for a two-dimensional network of directional C-H...{pi}-system interactions.

  8. Argument structure hierarchy system and method for facilitating analysis and decision-making processes

    DOE Patents [OSTI]

    Janssen, Terry

    2000-01-01

    A system and method for facilitating decision-making comprising a computer program causing linkage of data representing a plurality of argument structure units into a hierarchical argument structure. Each argument structure unit comprises data corresponding to a hypothesis and its corresponding counter-hypothesis, data corresponding to grounds that provide a basis for inference of the hypothesis or its corresponding counter-hypothesis, data corresponding to a warrant linking the grounds to the hypothesis or its corresponding counter-hypothesis, and data corresponding to backing that certifies the warrant. The hierarchical argument structure comprises a top level argument structure unit and a plurality of subordinate level argument structure units. Each of the plurality of subordinate argument structure units comprises at least a portion of the grounds of the argument structure unit to which it is subordinate. Program code located on each of a plurality of remote computers accepts input from one of a plurality of contributors. Each input comprises data corresponding to an argument structure unit in the hierarchical argument structure and supports the hypothesis or its corresponding counter-hypothesis. A second programming code is adapted to combine the inputs into a single hierarchical argument structure. A third computer program code is responsive to the second computer program code and is adapted to represent a degree of support for the hypothesis and its corresponding counter-hypothesis in the single hierarchical argument structure.

  9. Distributed Hierarchical Control of Multi-Area Power Systems with Improved Primary Frequency Regulation

    SciTech Connect (OSTI)

    Lian, Jianming; Marinovici, Laurentiu D.; Kalsi, Karanjit; Du, Pengwei; Elizondo, Marcelo A.

    2012-12-12

    The conventional distributed hierarchical control architecture for multi-area power systems is revisited. In this paper, a new distributed hierarchical control architecture is proposed. In the proposed architecture, pilot generators are selected in each area to be equipped with decentralized robust control as a supplementary to the conventional droop speed control. With the improved primary frequency control, the system frequency can be restored to the nominal value without the help of secondary frequency control, which reduces the burden of the automatic generation control for frequency restoration. Moreover, the low frequency inter-area electromechanical oscillations can also be effectively damped. The effectiveness of the proposed distributed hierarchical control architecture is validated through detailed simulations.

  10. Hierarchical ZnO Structures Templated with Amino Acid Based Surfactant...

    Office of Scientific and Technical Information (OSTI)

    Resource Type: Journal Article Resource Relation: Journal Name: Microporous and Mesoporous Materials, vol. 151, NA, March 15, 2012, pp. 64-69 Research Org: Lawrence Livermore ...

  11. Hierarchically Superstructured Prussian Blue Analogues: Spontaneous Assembly Synthesis and Applications as Pseudocapacitive Materials

    SciTech Connect (OSTI)

    Yue, Yanfeng; Zhang, Zhiyong; Binder, Andrew J.; Chen, Jihua; Jin, Xianbo; Overbury, Steven; Dai, Sheng

    2014-11-10

    Hierarchically superstructured Prussian blue analogues (hexa- conventional hybrid graphene/MnO2 nanostructured textiles. cyanoferrate, M = NiII, CoII and CuII) are synthesized through Because sodium or potassium ions are involved in energy stor- a spontaneous assembly technique. In sharp contrast to mac- age processes, more environmentally neutral electrolytes can roporous-only Prussian blue analogues, the hierarchically su- be utilized, making the superstructured porous Prussian blue perstructured porous Prussian blue materials are demonstrated analogues a great contender for applications as high-per- to possess a high capacitance, which is similar to those of the formance pseudocapacitors.

  12. Hierarchically Superstructured Prussian Blue Analogues: Spontaneous Assembly Synthesis and Applications as Pseudocapacitive Materials

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

    Yue, Yanfeng; Zhang, Zhiyong; Binder, Andrew J.; Chen, Jihua; Jin, Xianbo; Overbury, Steven; Dai, Sheng

    2014-11-10

    Hierarchically superstructured Prussian blue analogues (hexa- conventional hybrid graphene/MnO2 nanostructured textiles. cyanoferrate, M = NiII, CoII and CuII) are synthesized through Because sodium or potassium ions are involved in energy stor- a spontaneous assembly technique. In sharp contrast to mac- age processes, more environmentally neutral electrolytes can roporous-only Prussian blue analogues, the hierarchically su- be utilized, making the superstructured porous Prussian blue perstructured porous Prussian blue materials are demonstrated analogues a great contender for applications as high-per- to possess a high capacitance, which is similar to those of the formance pseudocapacitors.

  13. Hierarchical, ultrathin single-crystal nanowires of CdS conveniently produced in laser-induced thermal field

    SciTech Connect (OSTI)

    Han, Li -Li; Xin, Huolin L.; Kulinich, Sergei A.; Yang, Li -Jun; Du, Xi -Wen

    2015-07-16

    Hierarchical nanowires (HNWs) exhibit unique properties and have wide applications, while often suffering from imperfect structure. We report a facile strategy toward ultrathin CdS HNWs with monocrystal structure, where a continuous-wave (CW) Nd:YAG laser is employed to irradiate an oleic acid (OA) solution containing precursors and a light absorber. The high heating rate and large temperature gradient generated by the CW laser lead to the rapid formation of tiny zinc-blende CdS nanocrystals which then line up into nanowires with the help of OA molecules. Next, the nanowires experience a phase transformation from zinc-blende to wurtzite structure, and the transformation-induced stress creates terraces on their surface, which promotes the growth of side branches and eventually results in monocrystal HNWs with an ultrathin diameter of 24 nm. The one-step synthesis of HNWs is conducted in air and completes in just 40 seconds, thus being very simple and rapid. The prepared CdS HNWs display photocatalytic performance superior to their nanoparticle counterparts, thus showing promise for catalytic applications in the future.

  14. Hierarchical, ultrathin single-crystal nanowires of CdS conveniently produced in laser-induced thermal field

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

    Han, Li -Li; Xin, Huolin L.; Kulinich, Sergei A.; Yang, Li -Jun; Du, Xi -Wen

    2015-07-16

    Hierarchical nanowires (HNWs) exhibit unique properties and have wide applications, while often suffering from imperfect structure. We report a facile strategy toward ultrathin CdS HNWs with monocrystal structure, where a continuous-wave (CW) Nd:YAG laser is employed to irradiate an oleic acid (OA) solution containing precursors and a light absorber. The high heating rate and large temperature gradient generated by the CW laser lead to the rapid formation of tiny zinc-blende CdS nanocrystals which then line up into nanowires with the help of OA molecules. Next, the nanowires experience a phase transformation from zinc-blende to wurtzite structure, and the transformation-induced stressmore » creates terraces on their surface, which promotes the growth of side branches and eventually results in monocrystal HNWs with an ultrathin diameter of 24 nm. The one-step synthesis of HNWs is conducted in air and completes in just 40 seconds, thus being very simple and rapid. The prepared CdS HNWs display photocatalytic performance superior to their nanoparticle counterparts, thus showing promise for catalytic applications in the future.« less

  15. Photonic Design for Photovoltaics

    SciTech Connect (OSTI)

    Kosten, E.; Callahan, D.; Horowitz, K.; Pala, R.; Atwater, H.

    2014-08-28

    We describe photonic design approaches for silicon photovoltaics including i) trapezoidal broadband light trapping structures ii) broadband light trapping with photonic crystal superlattices iii) III-V/Si nanowire arrays designed for broadband light trapping.

  16. A new family of fluidic precursors for the self-templated synthesis of hierarchical nanoporous carbons

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

    Fulvio, Pasquale F; Hillesheim, Patrick C; Oyola, Yatsandra; Mahurin, Shannon Mark; Veith, Gabriel M; Dai, Sheng

    2013-01-01

    Hierarchical nanoporous nitrogen-doped carbons were prepared from task specific ionic liquids having a bis-imidazolium motif linked with various organic groups. While ethyl chains linking the imidazolium ions afford microporous-mesoporous carbons, long or aromatic groups resulted in microporous samples.

  17. Couplings between hierarchical conformational dynamics from multi-time correlation functions and two-dimensional lifetime spectra: Application to adenylate kinase

    SciTech Connect (OSTI)

    Ono, Junichi; Takada, Shoji; Saito, Shinji

    2015-06-07

    An analytical method based on a three-time correlation function and the corresponding two-dimensional (2D) lifetime spectrum is developed to elucidate the time-dependent couplings between the multi-timescale (i.e., hierarchical) conformational dynamics in heterogeneous systems such as proteins. In analogy with 2D NMR, IR, electronic, and fluorescence spectroscopies, the waiting-time dependence of the off-diagonal peaks in the 2D lifetime spectra can provide a quantitative description of the dynamical correlations between the conformational motions with different lifetimes. The present method is applied to intrinsic conformational changes of substrate-free adenylate kinase (AKE) using long-time coarse-grained molecular dynamics simulations. It is found that the hierarchical conformational dynamics arise from the intra-domain structural transitions among conformational substates of AKE by analyzing the one-time correlation functions and one-dimensional lifetime spectra for the donor-acceptor distances corresponding to single-molecule Förster resonance energy transfer experiments with the use of the principal component analysis. In addition, the complicated waiting-time dependence of the off-diagonal peaks in the 2D lifetime spectra for the donor-acceptor distances is attributed to the fact that the time evolution of the couplings between the conformational dynamics depends upon both the spatial and temporal characters of the system. The present method is expected to shed light on the biological relationship among the structure, dynamics, and function.

  18. Thermoelectric Materials by Design, Computational Theory and...

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

    by Design, Computational Theory and Structure Thermoelectric Materials by Design, Computational Theory and Structure 2009 DOE Hydrogen Program and Vehicle Technologies Program...

  19. A one-pot synthetic approach to prepare palladium nanoparticles embedded hierarchically porous TiO{sub 2} hollow spheres for hydrogen peroxide sensing

    SciTech Connect (OSTI)

    Kong Lirong; Lu Xiaofeng; Bian Xiujie; Zhang Wanjin; Wang Ce

    2010-10-15

    A simple one-step method to fabricate hierarchically porous TiO{sub 2}/Pd composite hollow spheres without any template was developed by using solvothermal treatment. Pd nanoparticles (2-5 nm) were well dispersed in the mesopores of the TiO{sub 2} hollow spheres via in-situ reduction. In our experiment, polyvinylpyrrolidone played an important role in the synthetic process as the reducing agent and the connective material between TiO{sub 2} and Pd nanoparticles. HF species generated from solvothermal reaction leaded to the formation of TiO{sub 2} hollow spheres and Ostwald ripening was another main factor that affected the size and structure of the hollow spheres. The as-prepared TiO{sub 2}/Pd composite hollow spheres exhibited high electrocatalytic activity towards the reduction of H{sub 2}O{sub 2}. The sensitivity was about 226.72 {mu}A mM{sup -1} cm{sup -2} with a detection limit of 3.81 {mu}M at a signal-to-noise ratio of 3. These results made the hierarchically porous TiO{sub 2}/Pd composite a promising platform for fabricating new nonenzymic biosensors. - Graphical Abstract: A new one-step solvothermal method was developed to prepare Pd nanoparticles embedded hierarchically porous TiO{sub 2} hollow spheres. Due to its unique nanostructure, the prepared TiO{sub 2}/Pd modified GC electrode exhibit a high sensitivity (226.72 {mu}A mM{sup -1} cm{sup -2}), a relatively low reduction potential (-0.2 V), a fast response time (<3 s) and a relatively low detection limit of 3.81 {mu}M (S/N=3) towards H{sub 2}O{sub 2}.

  20. Mapping a hierarchical control strategy onto a distributed system architecture

    SciTech Connect (OSTI)

    Manges, W.W.; Allgood, G.O.; Thompson, D.H.

    1988-01-01

    This paper describes the implementation of the control architecture for the Thermal Management System (TMS) developed for the Atomic Vapor Laser Isotope Separation Program (AVLIS) at the Oak Ridge Gaseous Diffusion Plant in Oak Ridge, Tennessee. It represents one of the major process control subsystems and is responsible for the overall thermal environment during the operational phases of the facility. The author's involvement included the conceptualization, development, design, and implementation of the overall control strategy along with the specification/configuration of the supporting hardware and software. 7 refs., 6 figs.

  1. Design/Installation and Structural Integrity Assessment of Bethel Valley Low-Level Waste Collection and transfer system upgrade for Building 2649 (Transported Waste Receiving Facility) at Oak Ridge National Laboratory

    SciTech Connect (OSTI)

    1995-01-01

    This document covers the design aspects of the new tank system and certifies that the design has sufficient structural integrity and is acceptable for storing or treating hazardous and/or radioactive substances. This issue identifies specific activities that must be completed during fabrication, installation, and testing of the new tank system in order to prove compliance of the final installation with governing requirements. The assessment is responsive to the Environmental Restoration Agreement for the Oak Ridge Reservation.

  2. Design Code Survey Form | Department of Energy

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

    Design Code Survey Form Design Code Survey Form Survey of Safety Software Used in Design of Structures, Systems, and Components 1. Introduction The Department's Implementation Plan ...

  3. The Case for A Hierarchal System Model for Linux Clusters

    SciTech Connect (OSTI)

    Seager, M; Gorda, B

    2009-06-05

    The computer industry today is no longer driven, as it was in the 40s, 50s and 60s, by High-performance computing requirements. Rather, HPC systems, especially Leadership class systems, sit on top of a pyramid investment mode. Figure 1 shows a representative pyramid investment model for systems hardware. At the base of the pyramid is the huge investment (order 10s of Billions of US Dollars per year) in semiconductor fabrication and process technologies. These costs, which are approximately doubling with every generation, are funded from investments multiple markets: enterprise, desktops, games, embedded and specialized devices. Over and above these base technology investments are investments for critical technology elements such as microprocessor, chipsets and memory ASIC components. Investments for these components are spread across the same markets as the base semiconductor processes investments. These second tier investments are approximately half the size of the lower level of the pyramid. The next technology investment layer up, tier 3, is more focused on scalable computing systems such as those needed for HPC and other markets. These tier 3 technology elements include networking (SAN, WAN and LAN), interconnects and large scalable SMP designs. Above these is tier 4 are relatively small investments necessary to build very large, scalable systems high-end or Leadership class systems. Primary among these are the specialized network designs of vertically integrated systems, etc.

  4. ARIA Cell Solenoid Design Considerations

    SciTech Connect (OSTI)

    Schulze, Martin E.

    2015-05-20

    Detailed schematics of the structure of the preliminary ARIA solenoid cell design including overhead and cross section views and dimensions.

  5. Civil Engineer (Structural)

    Broader source: Energy.gov [DOE]

    This position is located in Structural Design (TELD). The primary purpose of this position is to serve as a senior engineer responsible for loading, design, and analysis of all structures on BPA's...

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

    SciTech Connect (OSTI)

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

    2015-01-14

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

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

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

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

    2015-01-14

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

  8. Hierarchical mesoporous/microporous carbon with graphitized frameworks for high-performance lithium-ion batteries

    SciTech Connect (OSTI)

    Lv, Yingying; Fang, Yin; Qian, Xufang; Tu, Bo [Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Laboratory of Advanced Materials, Fudan University, Shanghai 200433 (China); Wu, Zhangxiong [Department of Chemical Engineering, Monash University, Clayton, VIC 3800 (Australia); Asiri, Abdullah M. [Chemistry Department and The Center of Excellence for Advanced Materials Research, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Zhao, Dongyuan, E-mail: dyzhao@fudan.edu.cn [Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Laboratory of Advanced Materials, Fudan University, Shanghai 200433 (China); Department of Chemical Engineering, Monash University, Clayton, VIC 3800 (Australia)

    2014-11-01

    A hierarchical meso-/micro-porous graphitized carbon with uniform mesopores and ordered micropores, graphitized frameworks, and extra-high surface area of ?2200 m{sup 2}/g, was successfully synthesized through a simple one-step chemical vapor deposition process. The commercial mesoporous zeolite Y was utilized as a meso-/ micro-porous template, and the small-molecule methane was employed as a carbon precursor. The as-prepared hierarchical meso-/micro-porous carbons have homogeneously distributed mesopores as a host for electrolyte, which facilitate Li{sup +} ions transport to the large-area micropores, resulting a high reversible lithium ion storage of 1000 mA h/g and a high columbic efficiency of 65% at the first cycle.

  9. Hierarchical Diagnosis R. A. Kropfli, S. Y. Matrosov, T. Uttal, and B. W. Orr

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

    R. A. Kropfli, S. Y. Matrosov, T. Uttal, and B. W. Orr National Oceanic and Atmospheric Administration/Environmental Research Laboratories Wave Propagation Laboratory Boulder, CO 80303 I ntrod uction The WPL 8-mm wavelength radar was designed with good sensitivity and resolution to observe the small-scale structure and microphysical properties of clouds. DuringASTEX, for example, it observed, with 37-m resolution, all marine boundary layer (MBL) stratus and stratocumulus clouds within 5 km of

  10. Control of entity interactions in a hierarchical variable resolution simulation

    SciTech Connect (OSTI)

    Powell, D.R.

    1997-08-01

    There has long been interest in variable resolution modeling to support military analysis for a broad range of interest areas. Despite the ever-present desire for models of greater fidelity at the expense of analysis and computation resources, models of moderate to low fidelity are still required at many levels of decision-making. Problems can arise due to the issue of consistency among the family of models used for analysis. To address this and other problems, models of variable resolution have been suggested. However, such variable resolution architectures inherently carry their own set of issues which must be resolved in order to be useful. First, what are the structural requirements for a variable resolution model; and second, how are interactions between entities governed, especially when the entities have different resolutions? This paper addresses these issues and discusses key mechanisms needed to develop a variable resolution combat simulation that meets several core requirements for such models: seamless aggregation/disaggregation, appropriate interactions between entities of differing resolution, and control of the aggregation/disaggregation process.

  11. Control of entity interactions in a hierarchical variable resolution simulation

    SciTech Connect (OSTI)

    Powell, D.R.

    1997-10-01

    There has long been interest in variable resolution modeling to support military analysis for a broad range of interest areas. Despite the ever-present desire for models of greater fidelity at the expense of analysis and computation resources, models of moderate to low fidelity are still required at many levels of decision-making. Problems can arise due to the issue of consistency among the family of models used for analysis. To address this and other problems, models of variable resolution have been suggested. However, such variable resolution architectures inherently carry their own set of issues which must be resolved in order to be useful. First, what are the structural requirements for a variable resolution model; and second, how are interactions between entities governed, especially when the entities have different resolutions? This paper addresses these issues and discusses key mechanisms needed to develop a variable resolution combat simulation that meets several core requirements for such models: seamless aggregation/disaggregation, appropriate interactions between entities of differing resolution, and control of the aggregation/disaggregation process.

  12. System Design Stage

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

    1997-05-21

    This chapter addresses translating the user-oriented functional design specifications into a set of technical, computer-oriented system design specifications; and designing the data structure and processes to the level of detail necessary to plan and execute the Programming and Installation Stages.

  13. Sliding coherence window technique for hierarchical detection of continuous gravitational waves

    SciTech Connect (OSTI)

    Pletsch, Holger J.

    2011-06-15

    A novel hierarchical search technique is presented for all-sky surveys for continuous gravitational-wave sources, such as rapidly spinning nonaxisymmetric neutron stars. Analyzing yearlong detector data sets over realistic ranges of parameter space using fully coherent matched-filtering is computationally prohibitive. Thus more efficient, so-called hierarchical techniques are essential. Traditionally, the standard hierarchical approach consists of dividing the data into nonoverlapping segments of which each is coherently analyzed, and subsequently the matched-filter outputs from all segments are combined incoherently. The present work proposes to break the data into subsegments shorter than the desired maximum coherence time span (size of the coherence window). Then matched-filter outputs from the different subsegments are efficiently combined by sliding the coherence window in time: Subsegments whose timestamps are closer than coherence window size are combined coherently, otherwise incoherently. Compared to the standard scheme at the same coherence time baseline, data sets longer by about 50-100% would have to be analyzed to achieve the same search sensitivity as with the sliding coherence window approach. Numerical simulations attest to the analytically estimated improvement.

  14. Hierarchical Ag/ZnO micro/nanostructure: Green synthesis and enhanced photocatalytic performance

    SciTech Connect (OSTI)

    Gao, Shuyan; Jia, Xiaoxia; Yang, Shuxia; Li, Zhengdao; Jiang, Kai

    2011-04-15

    Ag/ZnO metal-semiconductor nanocomposites with hierarchical micro/nanostructure have been prepared by the hydrothermal synthesis in the presence of bovine serum albumin (BSA). The results suggest that this biomolecule-assisted hydrothermal method is an efficient route for the fabrication of Ag/ZnO nanocomposites by using BSA both a shape controller and a reducing agent of Ag{sup +} ions. Moreover, Ag nanoparticles on the ZnO act as electron sinks, improving the separation of photogenerated electrons and holes, increasing the surface hydroxyl contents of ZnO, facilitating trapping the photoinduced electrons and holes to form more active hydroxyl radicals, and thus, enhancing the photocatalytic efficiency of ZnO. This is a good example for the organic combination of green chemistry and functional materials. -- Graphical Abstract: A green strategy is report to construct Ag/ZnO metal-semiconductor nanocomposites with hierarchical micro/nanostructure and enhanced photocatalytic activity. Display Omitted Research highlights: > Hierarchical micro/nanostructured Ag/ZnO nanocomposites have been prepared via a green route. > Ag nanoparticles improve the separation of photogenerated electrons and holes. > This facilitates trapping the photoinduced electrons and holes to form more hydroxyl radicals. Therefore, it enhances the photocatalytic efficiency of ZnO.

  15. Hierarchical Models for Batteries: Overview with Some Case Studies

    SciTech Connect (OSTI)

    Pannala, Sreekanth; Mukherjee, Partha P; Allu, Srikanth; Nanda, Jagjit; Martha, Surendra K; Dudney, Nancy J; Turner, John A

    2012-01-01

    Batteries are complex multiscale systems and a hierarchy of models has been employed to study different aspects of batteries at different resolutions. For the electrochemistry and charge transport, the models span from electric circuits, single-particle, pseudo 2D, detailed 3D, and microstructure resolved at the continuum scales and various techniques such as molecular dynamics and density functional theory to resolve the atomistic structure. Similar analogies exist for the thermal, mechanical, and electrical aspects of the batteries. We have been recently working on the development of a unified formulation for the continuum scales across the electrode-electrolyte-electrode system - using a rigorous volume averaging approach typical of multiphase formulation. This formulation accounts for any spatio-temporal variation of the different properties such as electrode/void volume fractions and anisotropic conductivities. In this talk the following will be presented: The background and the hierarchy of models that need to be integrated into a battery modeling framework to carry out predictive simulations, Our recent work on the unified 3D formulation addressing the missing links in the multiscale description of the batteries, Our work on microstructure resolved simulations for diffusion processes, Upscaling of quantities of interest to construct closures for the 3D continuum description, Sample results for a standard Carbon/Spinel cell will be presented and compared to experimental data, Finally, the infrastructure we are building to bring together components with different physics operating at different resolution will be presented. The presentation will also include details about how this generalized approach can be applied to other electrochemical storage systems such as supercapacitors, Li-Air batteries, and Lithium batteries with 3D architectures.

  16. Structural Materials

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

    Structural Materials Structural Materials Development enables advanced technologies through the discovery, development, and demonstration of cost-effective advanced structural materials for use in extreme environments (high-temperature, high-stress, erosive, and corrosive environments, including the performance of materials in contact with molten slags and salts). Research includes materials design and discovery, materials processing and manufacturing, and service-life prediction of materials

  17. Railway vehicle body structures

    SciTech Connect (OSTI)

    Not Available

    1985-01-01

    The strength and durability of railway vehicle structures is a major topic of engineering research and design. To reflect this importance the Railway Division of the Institution of Mechanical Engineers organised a conference to discuss all matters relating to railway vehicle design. This book presents the papers discussed in that conference. The contents include: Vehicle body design and the UIC's international contribution; LUL prototype 1986 stock - body structure; vehicle structure for the intermediate capacity transmit system vehicles; car body technology of advanced light rapid transit vehicles; concepts, techniques and experience in the idealization of car body structures for finite element analysis; Calcutta metropolitan railway; design for a lightweight diesel multiple unit body; the design of lightweight inter-city coal structures; the BREL international coach body shell structure; new concepts and design techniques versus material standards; structures of BR diesel electric freight locomotives; structural design philosophy for electric locomotives; suspension design for a locomotive with low structural frequencies; freight wagon structures; a finite element study of coal bodyside panels including the effects of joint flexibility; a fresh approach to the problem of car body design strength; energy absorption in automatic couplings and draw gear; passenger vehicle design loads and structural crashworthiness; design of the front part of railway vehicles (in case of frontal impact); the development of a theoretical technique for rail vehicle structural crashworthiness.

  18. Structure tracking aided design and synthesis of Li3V2(PO4)3 nanocrystals as high-power cathodes for lithium ion batteries

    SciTech Connect (OSTI)

    Wang, Liping; Bai, Jianming; Gao, Peng; Wang, Xiaoya; Looney, J. Patrick; Wang, Feng

    2015-07-30

    In this study, preparing new electrode materials with synthetic control of phases and electrochemical properties is desirable for battery applications but hardly achievable without knowing how the synthesis reaction proceeds. Herein, we report on structure tracking-aided design and synthesis of single-crystalline Li3V2(PO4)3 (LVP) nanoparticles with extremely high rate capability. A comprehensive investigation was made to the local structural orderings of the involved phases and their evolution toward forming LVP phase using in situ/ex situ synchrotron X-ray and electron-beam diffraction, spectroscopy, and imaging techniques. The results shed light on the thermodynamics and kinetics of synthesis reactions and enabled the design of a cost-efficient synthesis protocol to make nanocrystalline LVP, wherein solvothermal treatment is a crucial step leading to an amorphous intermediate with local structural ordering resembling that of LVP, which, upon calcination at moderate temperatures, rapidly transforms into the desired LVP phase. The obtained LVP particles are about 50 nm, coated with a thin layer of amorphous carbon and featured with excellent cycling stability and rate capability – 95% capacity retention after 200 cycles and 66% theoretical capacity even at a current rate of 10 C. The structure tracking based method we developed in this work offers a new way of designing battery electrodes with synthetic control of material phases and properties.

  19. Hierarchical Na-doped cubic ZrO{sub 2} synthesis by a simple hydrothermal route and its application in biodiesel production

    SciTech Connect (OSTI)

    Lara-Garca, Hugo A.; Romero-Ibarra, Issis C.; Pfeiffer, Heriberto

    2014-10-15

    Hierarchical growth of cubic ZrO{sub 2} phase was successfully synthesized via a simple hydrothermal process in the presence of different surfactants (cationic, non-ionic and anionic) and sodium hydroxide. The structural and microstructural characterizations of different ZrO{sub 2} powders were performed using various techniques, such as X-ray diffraction, transmission electron microscopy, N{sub 2} adsorptiondesorption, scanning electron microscopy and infrared. Results indicated that sodium addition stabilized the cubic ZrO{sub 2} phase by a Na-doping process, independently of the surfactant used. In contrast, microstructural characteristics varied as a function of the surfactant and sodium presence. In addition, water vapor (H{sub 2}O) and carbon dioxide (CO{sub 2}) sorption properties were evaluated on ZrO{sub 2} samples. Results evidenced that sample surface reactivity changed as a function of the sodium content. Finally, this surface reactivity was evaluated on the biodiesel transesterification reaction using the different synthesized samples, obtaining yields of 93%. - Graphical abstract: Hierarchical growth of cubic Na-ZrO{sub 2} phase was synthesized by hydrothermal processes in the presence of surfactants and sodium. Sodium addition stabilized the cubic phase by a Na-doping process, while the microstructural characteristics varied with surfactants. Finally, this surface reactivity was evaluated on the biodiesel transesterification reaction. - Highlights: Cubic-ZrO{sub 2} phase was synthesized via a simple hydrothermal process. ZrO{sub 2} structure and microstructures changed as a function of the surfactant. Cubic-ZrO{sub 2} phase was evaluated on the biodiesel transesterification reaction.

  20. Labs21 sustainable design programming checklist version 1.0

    SciTech Connect (OSTI)

    Mathew, Paul; Greenberg, Steve

    2005-01-07

    This checklist of sustainable design objectives and strategies can be used in the programming and conceptual design phases of a laboratory project. It includes the following: (1) Brief descriptions of each objective and strategy. (2) Metrics for each objective. This checklist is primarily to be used by owners, architects and engineers during the programming and conceptual design phase of a project. It is especially appropriate for use in design charrettes. The strategies and metrics can be included as requirements in the programming document or can be identified for further analysis or consideration during the design development phase. This checklist is hierarchically organized into design areas, objectives for each design area, and strategies and metrics for each objective. The design areas generally correspond to the design areas of the LEED(TM) rating system from the U.S. Green Building Council.

  1. Real-Time Combined Heat and Power Operational Strategy Using a Hierarchical Optimization Algorithm

    SciTech Connect (OSTI)

    Yun, Kyung Tae; Cho, Heejin; Luck, Rogelio; Mago, Pedro J.

    2011-06-01

    Existing attempts to optimize the operation of Combined Heat and Power (CHP) systems for building applications have two major limitations: the electrical and thermal loads are obtained from historical weather profiles; and the CHP system models ignore transient responses by using constant equipment efficiencies. This paper considers the transient response of a building combined with a hierarchical CHP optimal control algorithm to obtain a real-time integrated system that uses the most recent weather and electric load information. This is accomplished by running concurrent simulations of two transient building models. The first transient building model uses current as well as forecast input information to obtain short term predictions of the thermal and electric building loads. The predictions are then used by an optimization algorithm, i.e., a hierarchical controller, that decides the amount of fuel and of electrical energy to be allocated at the current time step. In a simulation, the actual physical building is not available and, hence, to simulate a real-time environment, a second, building model with similar but not identical input loads are used to represent the actual building. A state-variable feedback loop is completed at the beginning of each time step by copying, i.e., measuring, the state variable from the actual building and restarting the predictive model using these ?measured? values as initial conditions. The simulation environment presented in this paper features nonlinear effects such as the dependence of the heat exchanger effectiveness on their operating conditions. The results indicate that the CHP engine operation dictated by the proposed hierarchical controller with uncertain weather conditions have the potential to yield significant savings when compared to conventional systems using current values of electricity and fuel prices.

  2. Hierarchical Diagnosis

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

    Development of a Rad iative Cloud Parameterization Scheme of Stratocumulus and Stratus Clouds Which Includes the Impact of Cloud Condensation Nucleus on Cloud Albedo W. R. Cotton, G. L. Stephens, D. Duda, B. Stevens, and R. L. Walko Colorado State University Department of Atmospheric Science Fort Collins, CO G. Feingold Cooperative Institute for Research in Environmental Sciences University of Colorado, Boulder Boulder. CO 80309-0049 A three-dimensional (3-D) model for simulating the effect of

  3. Hierarchical Diagnosis

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

    Theoretical Studies of Radiative Properties of Broken Clouds G. A. Titov Institute of Atmospheric Optics Russian Academy of Science T omsk, Russia One of the three major goals of the Atmospheric Radiation Measurement (ARM) Program is to improve the quality of radiation models under clear sky, homogeneous cloud, and broken cloud conditions. This report is concerned with the development of the theory of radiation transfer in the broken clouds. Our approach is based on a stochastic description of

  4. A prototype functional language implementation for hierarchical- memory architectures. Revision 1

    SciTech Connect (OSTI)

    Wolski, R.; Feo, J.; Cann, D.

    1992-01-14

    Programming languages are the most important tool at a programmers` disposal. All other tools correct, visualize, or evaluate the product crafted by this tool. The advent of multiprocessor computer systems has greatly complicated the programmer`s task an increased his need for high-level languages capable of automatically taming these architectures. In this paper, we describe a prototype implementation of Sisal for multiprocessor, hierarchical-memory systems. The implementation includes explicit compiler and runtime control that effectively exploits the different levels of memory and manages interprocess communications (IPC). We give preliminary performance results for this system on the BBN TC2000.

  5. Foundation Design Handbook

    SciTech Connect (OSTI)

    Carmody, John; Mosiman, Garrett; Handeen, Daniel; Huelman, Patrick; Christian, Jeffery

    2013-10-01

    The purpose of this handbook is to provide information that will enable designers, builders, and homeowners to understand foundation design problems and solutions. The foundation of a house is a somewhat invisible and sometimes ignored component of the building. It is increasingly evident, however, that attention to good foundation design and construction has significant benefits to the homeowner and the builder, and can avoid some serious future problems. Good foundation design and construction practice means not only insulating to save energy, but also providing effective structural design as well as moisture, termite, and radon control techniques where appropriate.

  6. Preliminary Structural Design Conceptualization for Composite Rotor for Verdant Power Water Current: Cooperative Research and Development Final Report, CRADA Number CRD-08-296

    SciTech Connect (OSTI)

    Hughes, S.

    2011-02-01

    The primary thrust of the CRADA will be to develop a new rotor design that will allow higher current flows (>4m/s), greater swept area (6-11m), and in the process, will maximize performance and energy capture.

  7. Structure for Storing Properties of Particles (PoP)

    SciTech Connect (OSTI)

    Patel, N. R.; Mattoon, C. M.; Beck, B. R.; Summers, N. C.; Brown, D. A.

    2014-06-01

    Some evaluated nuclear databases are critical for applications such as nuclear energy, nuclear medicine, homeland security, and stockpile stewardship. Particle masses, nuclear excitation levels, and other “Properties of Particles” are essential for making evaluated nuclear databases. Currently, these properties are obtained from various databases that are stored in outdated formats. Moreover, the “Properties of Particles” (PoP) structure is being designed that will allow storing all information for one or more particles in a single place, so that each evaluation, simulation, model calculation, etc. can link to the same data. Information provided in PoP will include properties of nuclei, gammas and electrons (along with other particles such as pions, as evaluations extend to higher energies). Presently, PoP includes masses from the Atomic Mass Evaluation version 2003 (AME2003), and level schemes and gamma decays from the Reference Input Parameter Library (RIPL-3). The data are stored in a hierarchical structure. An example of how PoP stores nuclear masses and energy levels will be presented here.

  8. Cable deformation simulation and a hierarchical framework for Nb3Sn Rutherford cables

    SciTech Connect (OSTI)

    Arbelaez, D.; Prestemon, S. O.; Ferracin, P.; Godeke, A.; Dietderich, D. R.; Sabbi, G.

    2009-09-13

    Knowledge of the three-dimensional strain state induced in the superconducting filaments due to loads on Rutherford cables is essential to analyze the performance of Nb{sub 3}Sn magnets. Due to the large range of length scales involved, we develop a hierarchical computational scheme that includes models at both the cable and strand levels. At the Rutherford cable level, where the strands are treated as a homogeneous medium, a three-dimensional computational model is developed to determine the deformed shape of the cable that can subsequently be used to determine the strain state under specified loading conditions, which may be of thermal, magnetic, and mechanical origins. The results can then be transferred to the model at the strand/macro-filament level for rod restack process (RRP) strands, where the geometric details of the strand are included. This hierarchical scheme can be used to estimate the three-dimensional strain state in the conductor as well as to determine the effective properties of the strands and cables from the properties of individual components. Examples of the modeling results obtained for the orthotropic mechanical properties of the Rutherford cables are presented.

  9. Accelerator Design and Development | Argonne National Laboratory

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

    Accelerator Design and Development Accelerator Design and Development Scientists around the world rely on particle accelerators to yield insights on the structure and function of ...

  10. Designing optical metamaterial with hyperbolic dispersion based on Al:ZnO/ZnO nano-layered structure using Atomic Layer Deposition technique

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

    Kelly, Priscilla; Liu, Mingzhao; Kuznetsova, Lyuba

    2016-04-07

    In this study, nano-layered Al:ZnO/ZnO hyperbolic dispersion metamaterial with a large number of layers was fabricated using the atomic layer deposition (ALD) technique. Experimental dielectric functions for Al:ZnO/ZnO structures are obtained by an ellipsometry technique in the visible and near-infrared spectral ranges. The theoretical modeling of the Al:ZnO/ZnO dielectric permittivity is done using effective medium approximation. A method for analysis of spectroscopic ellipsometry data is demonstrated to extract the optical permittivity for this highly anisotropic nano-layered metamaterial. The results of the ellipsometry analysis show that Al:ZnO/ZnO structures with a 1:9 ALD cycle ratio exhibit hyperbolic dispersion transition change near 1.8more » μm wavelength.« less