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Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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1

From Protein Structure to Function: Ring Cycle for Dilating and...  

NLE Websites -- All DOE Office Websites (Extended Search)

From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore From Protein Structure to Function: Ring Cycle for Dilating and Constricting the...

2

Structure and electronic properties of saturated and unsaturated gallium nitride nanotubes  

DOE Green Energy (OSTI)

The atomic and electronic structures of saturated and unsaturated GaN nanotubes along the [001] direction with (100) lateral facets are studied using first-principles calculations. Atomic relaxation of nanotubes shows that appreciable distortion occurs in the unsaturated nanotubes. All the nanotubes considered, including saturated and unsaturated ones, exhibit semiconducting, with a direct band gap. Surface states arisen from the threefold-coordinated N and Ga atoms at the lateral facets exist inside the bulk-like band gap. When the nanotubes saturated with hydrogen, these dangling bond bands are removed from the band gap, but the band gap decreases with increasing the wall thickness of the nanotubes.

Wang, Zhiguo; Wang, Shengjie; Li, Jingbo; Gao, Fei; Weber, William J.

2009-11-05T23:59:59.000Z

3

The Physical Oceanography of Two Rings Observed by the Cyclonic Ring Experiment. Part I: Physical Structures  

Science Conference Proceedings (OSTI)

Eight cruises over a 10-month period in the North Atlantic have provided the Cyclonic Ring Experiment with observations of two rings. Life histories, structure and structural changes have been studied with emphasis on the effects of Stream ...

Andrew C. Vastano; Joyce E. Schmitz; Denise E. Hagan

1980-04-01T23:59:59.000Z

4

Structured LDPC codes over integer residue rings  

Science Conference Proceedings (OSTI)

This paper presents a new class of low-density parity-check (LDPC) codes over Z2a represented by regular, structured Tanner graphs. These graphs are constructed using Latin squares defined over a multiplicative group of a Galois ...

Elisa Mo; Marc A. Armand

2008-01-01T23:59:59.000Z

5

From Protein Structure to Function: Ring Cycle for Dilating and  

NLE Websites -- All DOE Office Websites (Extended Search)

From Protein Structure to From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print Wednesday, 28 August 2013 00:00 Nuclear pore complexes (NPCs) act as the central gatekeepers for selective transport between the cytoplasm and the nucleus. They allow the exchange of selected proteins and ribonucleoproteins, while preventing the transport of material not meant to cross the nuclear envelope. The NPC transport channel is the largest and most complex transport conduit in the eukaryotic kingdom and it is likely composed of only 3 out of 30 nuclear pore complex proteins (nups). Researchers from the Howard Hughes Medical Institute at the Rockefeller University have determined crystal structures of interacting domains of these centrally located channel nups, Nup54, Nup58, and Nup62, using data collected at ALS Beamline 8.2.1. These structures allowed them to elucidate the molecular mechanism that underlies large-scale diameter changes of NPCs and propose a 'ring cycle' for dilating and constricting NPCs from 10-50 nm. The ring cycle would provide a method to adjust transport activities to cellular demands with a rapid response time.

6

From Protein Structure to Function: Ring Cycle for Dilating and  

NLE Websites -- All DOE Office Websites (Extended Search)

From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print Nuclear pore complexes (NPCs) act as the central gatekeepers for selective transport between the cytoplasm and the nucleus. They allow the exchange of selected proteins and ribonucleoproteins, while preventing the transport of material not meant to cross the nuclear envelope. The NPC transport channel is the largest and most complex transport conduit in the eukaryotic kingdom and it is likely composed of only 3 out of 30 nuclear pore complex proteins (nups). Researchers from the Howard Hughes Medical Institute at the Rockefeller University have determined crystal structures of interacting domains of these centrally located channel nups, Nup54, Nup58, and Nup62, using data collected at ALS Beamline 8.2.1. These structures allowed them to elucidate the molecular mechanism that underlies large-scale diameter changes of NPCs and propose a 'ring cycle' for dilating and constricting NPCs from 10-50 nm. The ring cycle would provide a method to adjust transport activities to cellular demands with a rapid response time.

7

From Protein Structure to Function: Ring Cycle for Dilating and  

NLE Websites -- All DOE Office Websites (Extended Search)

From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print From Protein Structure to Function: Ring Cycle for Dilating and Constricting the Nuclear Pore Print Nuclear pore complexes (NPCs) act as the central gatekeepers for selective transport between the cytoplasm and the nucleus. They allow the exchange of selected proteins and ribonucleoproteins, while preventing the transport of material not meant to cross the nuclear envelope. The NPC transport channel is the largest and most complex transport conduit in the eukaryotic kingdom and it is likely composed of only 3 out of 30 nuclear pore complex proteins (nups). Researchers from the Howard Hughes Medical Institute at the Rockefeller University have determined crystal structures of interacting domains of these centrally located channel nups, Nup54, Nup58, and Nup62, using data collected at ALS Beamline 8.2.1. These structures allowed them to elucidate the molecular mechanism that underlies large-scale diameter changes of NPCs and propose a 'ring cycle' for dilating and constricting NPCs from 10-50 nm. The ring cycle would provide a method to adjust transport activities to cellular demands with a rapid response time.

8

Lipid Analysis and Lipidomics: New Techniques & Application-Ch 6Structural Analysis of Unsaturated Fatty Acid Methyl Ester Isomers with Acetonitrile Covalent Adduct Chemical Ionization  

Science Conference Proceedings (OSTI)

Lipid Analysis and Lipidomics: New Techniques & Application-Ch 6 Structural Analysis of Unsaturated Fatty Acid Methyl Ester Isomers with Acetonitrile Covalent Adduct Chemical Ionization Methods and Analyses eChapters Methods - Analyses Book

9

Structure and assembly of the essential RNA ring component of a viral DNA packaging motor  

SciTech Connect

Prohead RNA (pRNA) is an essential component in the assembly and operation of the powerful bacteriophage {psi}29 DNA packaging motor. The pRNA forms a multimeric ring via intermolecular base-pairing interactions between protomers that serves to guide the assembly of the ring ATPase that drives DNA packaging. Here we report the quaternary structure of this rare multimeric RNA at 3.5 {angstrom} resolution, crystallized as tetrameric rings. Strong quaternary interactions and the inherent flexibility helped rationalize how free pRNA is able to adopt multiple oligomerization states in solution. These characteristics also allowed excellent fitting of the crystallographic pRNA protomers into previous prohead/pRNA cryo-EM reconstructions, supporting the presence of a pentameric, but not hexameric, pRNA ring in the context of the DNA packaging motor. The pentameric pRNA ring anchors itself directly to the phage prohead by interacting specifically with the fivefold symmetric capsid structures that surround the head-tail connector portal. From these contacts, five RNA superhelices project from the pRNA ring, where they serve as scaffolds for binding and assembly of the ring ATPase, and possibly mediate communication between motor components. Construction of structure-based designer pRNAs with little sequence similarity to the wild-type pRNA were shown to fully support the packaging of {psi}29 DNA.

Ding, Fang; Lu, Changrui; Zhao, Wei; Rajashankar, Kanagalaghatta R.; Anderson, Dwight L.; Jardine, Paul J.; Grimes, Shelley; Ke, Ailong (Cornell); (UMM)

2011-07-25T23:59:59.000Z

10

Hexameric ring structure of the N-terminal domain of Mycobacterium tuberculosis DnaB helicase  

Science Conference Proceedings (OSTI)

Hexameric DnaB helicase unwinds the DNA double helix during replication of genetic material in bacteria. DnaB is an essential bacterial protein; therefore, it is an important potential target for antibacterial drug discovery. We report a crystal structure of the N-terminal region of DnaB from the pathogen Mycobacterium tuberculosis (MtDnaBn), determined at 2.0 {angstrom} resolution. This structure provides atomic resolution details of formation of the hexameric ring of DnaB by two distinct interfaces. An extensive hydrophobic interface stabilizes a dimer of MtDnaBn by forming a four-helix bundle. The other, less extensive, interface is formed between the dimers, connecting three of them into a hexameric ring. On the basis of crystal packing interactions between MtDnaBn rings, we suggest a model of a helicase-primase complex that explains previously observed effects of DnaB mutations on DNA priming.

Biswas, Tapan; Tsodikov, Oleg V. (Michigan)

2009-01-15T23:59:59.000Z

11

Experimental unsaturated soil mechanics  

E-Print Network (OSTI)

In this general report, experimental systems and procedures of investigating the hydro-mechanical behaviour of unsaturated soils are presented. The water retention properties of unsaturated soils are commented and linked to various physical parameters and properties of the soils. Techniques of controlling suction are described together with their adaptation in various laboratory testing devices. Some typical features of the mechanical behaviour of unsaturated soils are presented within an elasto-plastic framework. An attempt to describe the numerous and significant recent advances in the investigation of the behaviour of unsaturated soils, including the contributions to this Conference, is proposed.

Delage, Pierre

2008-01-01T23:59:59.000Z

12

RECA: a ring-structured energy-efficient clustering architecture for robust communication in wireless sensor networks  

Science Conference Proceedings (OSTI)

Clustering methods have shown their promising effects in the conservation of energy in Wireless Sensor Networks (WSNs). In this paper, we present a Ring-structured Energy-efficient Clustering Architecture (RECA) for WSNs to prolong ... Keywords: WSNs, cluster head management, energy efficiency, load balancing algorithms, network lifetime, ring-structured clustering, simulation, wireless networks, wireless sensor networks

Guanfeng Li; Taieb Znati

2007-04-01T23:59:59.000Z

13

THE CHEMICAL EVOLUTION OF THE MONOCEROS RING/GALACTIC ANTICENTER STELLAR STRUCTURE  

Science Conference Proceedings (OSTI)

The origin of the Galactic Anticenter Stellar Structure (GASS) or 'Monoceros Ring' - a low-latitude overdensity at the edge of the Galactic disk spanning at least the second and third Galactic quadrants-remains controversial. Models for the origin of GASS generally fall into scenarios where either it is a part (e.g., warp) of the Galactic disk or it represents tidal debris from the disruption of a Milky Way (MW) satellite galaxy. To further constrain models for the origin of GASS, we derive chemical abundance patterns from high-resolution spectra for 21 M giants spatially and kinematically identified with it. The abundances of the (mostly) {alpha}-element, titanium, and s-process elements, yttrium and lanthanum, for these GASS stars are found to be lower at the same [Fe/H] than those for MW stars, but similar to those of stars in the Sagittarius stream, other dwarf spheroidal galaxies, and the Large Magellanic Cloud. This demonstrates that GASS stars have a chemical enrichment history typical of dwarf galaxies-and unlike those of typical MW stars (at least MW stars near the Sun). Nevertheless, these abundance results cannot definitively rule out the possibility that GASS was dynamically created out of a previously formed, outer MW disk because {Lambda}CDM-based structure formation models show that galactic disks grow outward by accretion of dwarf galaxies. On the other hand, the chemical patterns seen in GASS stars do provide striking verification that accretion of dwarf galaxies has indeed happened at the edge of the MW disk.

Chou Meiyin; Majewski, Steven R.; Patterson, Richard J. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325 (United States); Cunha, Katia; Smith, Verne V. [National Optical Astronomy Observatories, P.O. Box 26732, Tucson, AZ 85726 (United States); MartInez-Delgado, David, E-mail: mc6ss@virginia.ed, E-mail: srm4n@virginia.ed, E-mail: rjp0i@virginia.ed, E-mail: cmy@asiaa.sinica.edu.t, E-mail: cunha@noao.ed, E-mail: vsmith@noao.ed, E-mail: ddelgado@iac.e [Instituto de Astrofisica de Canarias, La Laguna (Spain)

2010-09-01T23:59:59.000Z

14

Modeling the structural behavior of the piston rings under different boundary conditions in internal combustion engines  

E-Print Network (OSTI)

In the process of designing internal combustion engine, piston ring plays an important role in fulfilling the requirements of camber gas sealing, friction reduction and lubrication oil consumption. The goal of this thesis ...

Xu, Dian

2010-01-01T23:59:59.000Z

15

Structure of the gating ring from the human large-conductance Ca[superscript 2+]-gated K[superscript +] channel  

SciTech Connect

Large-conductance Ca{sup 2+}-gated K{sup +} (BK) channels are essential for many biological processes such as smooth muscle contraction and neurotransmitter release. This group of channels can be activated synergistically by both voltage and intracellular Ca{sup 2+}, with the large carboxy-terminal intracellular portion being responsible for Ca{sup 2+} sensing. Here we present the crystal structure of the entire cytoplasmic region of the human BK channel in a Ca{sup 2+}-free state. The structure reveals four intracellular subunits, each comprising two tandem RCK domains, assembled into a gating ring similar to that seen in the MthK channel and probably representing its physiological assembly. Three Ca{sup 2+} binding sites including the Ca{sup 2+} bowl are mapped onto the structure based on mutagenesis data. The Ca{sup 2+} bowl, located within the second RCK domain, forms an EF-hand-like motif and is strategically positioned close to the assembly interface between two subunits. The other two Ca{sup 2+} (or Mg{sup 2+}) binding sites, Asp367 and Glu374/Glu399, are located on the first RCK domain. The Asp367 site has high Ca{sup 2+} sensitivity and is positioned in the groove between the amino- and carboxy-terminal subdomains of RCK1, whereas the low-affinity Mg{sup 2+}-binding Glu374/Glu399 site is positioned on the upper plateau of the gating ring and close to the membrane. Our structure also contains the linker connecting the transmembrane and intracellular domains, allowing us to dock a voltage-gated K{sup +} channel pore of known structure onto the gating ring with reasonable accuracy and generate a structural model for the full BK channel.

Wu, Yunkun; Yang, Yi; Ye, Sheng; Jiang, Youxing (Zhejiang); (UTSMC)

2010-11-12T23:59:59.000Z

16

A thermal active restrained shrinkage ring test to study the early age concrete behaviour of massive structures  

Science Conference Proceedings (OSTI)

In massive concrete structures, cracking may occur during hardening, especially if autogenous and thermal strains are restrained. The concrete permeability due to this cracking may rise significantly and thus increase leakage (in tank, nuclear containment...) and reduce the durability. The restrained shrinkage ring test is used to study the early age concrete behaviour (delayed strains evolution and cracking). This test shows, at 20 {sup o}C and without drying, for a concrete mix which is representative of a French nuclear power plant containment vessel (w/c ratio equal to 0.57), that the amplitude of autogenous shrinkage (about 40 {mu}m/m for the studied concrete mix) is not high enough to cause cracking. Indeed, in this configuration, thermal shrinkage is not significant, whereas this is a major concern for massive structures. Therefore, an active test has been developed to study cracking due to restrained thermal shrinkage. This test is an evolution of the classical restrained shrinkage ring test. It allows to take into account both autogenous and thermal shrinkages. Its principle is to create the thermal strain effects by increasing the temperature of the brass ring (by a fluid circulation) in order to expand it. With this test, the early age cracking due to restrained shrinkage, the influence of reinforcement and construction joints have been experimentally studied. It shows that, as expected, reinforcement leads to an increase of the number of cracks but a decrease of crack widths. Moreover, cracking occurs preferentially at the construction joint.

Briffaut, M. [LMT/ENS Cachan/CNRS UMR8535/UPMC/PRES UniverSud Paris, Cachan (France); Institut de radioprotection et de surete nucleaire, Fontenay-aux-Roses (France); Benboudjema, F. [LMT/ENS Cachan/CNRS UMR8535/UPMC/PRES UniverSud Paris, Cachan (France); Torrenti, J.M., E-mail: jean-michel.torrenti@lcpc.f [Universite Paris Est, Laboratoire central des ponts et chaussees, Paris (France); Nahas, G. [LMT/ENS Cachan/CNRS UMR8535/UPMC/PRES UniverSud Paris, Cachan (France); Institut de radioprotection et de surete nucleaire, Fontenay-aux-Roses (France)

2011-01-15T23:59:59.000Z

17

Structure and Bonding in Carbon Clusters C{sub 14} to C{sub 24} : Chains, Rings, Bowls, Plates, and Cages  

SciTech Connect

Density functional calculations have been performed for many isomers of carbon clusters C{sub n} (14{le}n{le}24 , n even) using both local spin density and gradient-corrected approximations to the exchange-correlation energy. The stable isomers include chains, rings, graphitic ({open_quotes}plate{close_quotes} and {open_quotes}bowl{close_quotes}), and cagelike structures, and we observe a fourfold periodicity in several structural classes, not only the monocyclic rings. Stable cages exist for all clusters, and double rings are less stable than the monocyclic rings. Gradient corrections are significant, but quite regular within a given structural type. The bonding trends found should also apply to larger clusters. {copyright} {ital 1997} {ital The American Physical Society}

Jones, R.O. [Institut fuer Festkoerperforschung, Forschungszentrum Juelich, D-52425 Juelich (Germany)] [Institut fuer Festkoerperforschung, Forschungszentrum Juelich, D-52425 Juelich (Germany); Seifert, G. [Institut fuer Theoretische Physik, Technische Universitaet Dresden, D-01062 Dresden (Germany)] [Institut fuer Theoretische Physik, Technische Universitaet Dresden, D-01062 Dresden (Germany)

1997-07-01T23:59:59.000Z

18

A new 3D nickel(II) framework composed of large rings: Ionothermal synthesis and crystal structure  

SciTech Connect

Ionothermal reaction between Ni{sup 2+} and 1,3,5-benzentricarboxylic acid (H{sub 3}BTC) with [AMI]Cl (AMI=1-amyl-3-methylimidazolium) as the reaction medium produced a novel 3D mixed-ligand metal-organic framework [AMI][Ni{sub 3}(BTC){sub 2}(OAc)(MI){sub 3}] (1) (MI=1-methylimidazole) with [AMI]{sup +} incorporated in the framework. The framework is formed by connecting 2D planes, made up of 32- and 48-membered rings, through 1D chains composed of 32-membered rings. The two BTC{sup 3-} ligands in 1 show the same connectivity mode with two bidentate and one {mu}{sub 2} bridging carboxylic groups. This is a new connectivity mode to the already existing 17 in the Ni-BTC system. The role of MI and [AMI]Cl in the structure formation is discussed. - Graphical Abstract: A novel 3D framework [AMI][Ni{sub 3}(BTC){sub 2}(OAc)(MI){sub 3}] is obtained in ionothermal system with [AMI]{sup +} incorporating in the cavities as structure directing template and BTC{sup 3-} showing a new coordination fashion. The 3D framework is constructed by 2D layers linked with 1D double chains. The title compound has the middle thermal stability at ca. 280 deg. C.

Xu Ling [Department of Chemistry, BK-21 School of Chemical Materials Sciences, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Choi, Eun-Young [Institute of Basic Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kwon, Young-Uk [Department of Chemistry, BK-21 School of Chemical Materials Sciences, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Institute of Basic Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); SKKU Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)], E-mail: ywkwon@skku.edu

2008-11-15T23:59:59.000Z

19

Electropositive bivalent metallic ion unsaturated polyester complexed polymer concrete  

DOE Patents (OSTI)

Quick setting polymer concrete compositions which are mixtures of unsaturated polyesters and crosslinking monomers together with appropriate initiators and promoters in association with aggregate which may be wet and a source of bivalent metallic ions which will set to polymer concrete with excellent structural properties.

Sugama, T.; Kukacka, L.E.; Horn, W.H.

1981-11-04T23:59:59.000Z

20

Electropositive bivalent metallic ion unsaturated polyester complexed polymer concrete  

DOE Patents (OSTI)

Quick setting polymer concrete compositions with excellent structural properties are disclosed; these polymer concrete compositions are mixtures of unsaturated polyesters and crosslinking monomers together with appropriate initiators and promoters in association with aggregate, which may be wet, and with a source of bivalent metallic ions.

Sugama, Toshifumi (Mastic Beach, NY); Kukacka, Lawrence E. (Port Jefferson, NY); Horn, William H. (Brookhaven, NY)

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Electropositive bivalent metallic ion unsaturated polyester complexed polymer concrete  

DOE Patents (OSTI)

Quick setting polymer concrete compositions are described which are mixtures of unsaturated polyesters and crosslinking monomers together with appropriate initiators and promoters in association with aggregate which may be wet and a source of bivalent metallic ions which will set to polymer concrete with excellent structural properties.

Sugama, T.; Kukacka, L.E.; Horn, W.H.

1983-05-13T23:59:59.000Z

22

NSLS Ring Parameters  

NLE Websites -- All DOE Office Websites (Extended Search)

Ring Parameters VUV Ring Parameters X-Ray Ring Parameters Booster Ring Parameters Map of Experimental Floor (jpg)...

23

Fault Tolerant Active Rings for Structured Peer-to-Peer Overlays  

Science Conference Proceedings (OSTI)

Algorithms by which peers join and leave structured overlay networks can be classified as passive or active. Passive topology maintenance relies on periodic background repair of neighbor pointers. When a node passively leaves the overlay, subsequent ...

John Risson; Ken Robinson; Tim Moors

2005-11-01T23:59:59.000Z

24

Black ring deconstruction  

E-Print Network (OSTI)

rotating black holes from 5d black rings,” hep-th/0504125. [fuzzball proposal for black holes: An elementary review,”The quantum structure of black holes,” hep-th/0510180. [5

Gimon, Eric G.

2008-01-01T23:59:59.000Z

25

Allosteric Activation of E2-RING Finger-Mediated Ubiquitylation by a Structurally Defined Specific E2-Binding Region of gp78  

SciTech Connect

The activity of RING finger ubiquitin ligases (E3) is dependent on their ability to facilitate transfer of ubiquitin from ubiquitin-conjugating enzymes (E2) to substrates. The G2BR domain within the E3 gp78 binds selectively and with high affinity to the E2 Ube2g2. Through structural and functional analyses, we determine that this occurs on a region of Ube2g2 distinct from binding sites for ubiquitin-activating enzyme (E1) and RING fingers. Binding to the G2BR results in conformational changes in Ube2g2 that affect ubiquitin loading. The Ube2g2:G2BR interaction also causes an 50-fold increase in affinity between the E2 and RING finger. This results in markedly increased ubiquitylation by Ube2g2 and the gp78 RING finger. The significance of this G2BR effect is underscored by enhanced ubiquitylation observed when Ube2g2 is paired with other RING finger E3s. These findings uncover a mechanism whereby allosteric effects on an E2 enhance E2-RING finger interactions and, consequently, ubiquitylation.

Das, Ranabir; Mariano, Jennifer; Tsai, Yien Che; Kalathur, Ravi C.; Kostova, Zlatka; Li, Jess; Tarasov, Sergey G.; McFeeters, Robert L.; Altieri, Amanda S.; Ji, Xinhua; Byrd, R. Andrew; Weissman, Allan M.; (NCI)

2010-11-12T23:59:59.000Z

26

Observations on the flow structures and transport in a warm-core ring in the Gulf of Mexico  

E-Print Network (OSTI)

This study presents several new observations from the study of a warm-core ring (WCR) in the Gulf of Mexico based on the ECCO2 global ocean simulation. Using Lagrangian coherent structures (LCS) techniques to investigate this flow reveals a pattern of transversely intersecting LCS in the mixed layer of the WCR which experiences consistent stretching behavior over a large region of space and time. A detailed analysis of this flow region leads to an analytical model velocity field which captures the essential elements that generate the transversely intersecting LCS. The model parameters are determined from the WCR and the resulting LCS show excellent agreement with those observed in the WCR. The three-dimensional transport behavior which creates these structures relies on the small radial outflow which is present in the mixed layer and is not seen below the pycnocline, leading to a sharp change in the character of the LCS at the bottom of the mixed layer. The flow behavior revealed by the LCS limits fluid excha...

Lipinski, Doug

2013-01-01T23:59:59.000Z

27

Numerical simulation of unsaturated soil behaviour  

Science Conference Proceedings (OSTI)

The mechanical behaviour of unsaturated soils is one of the challenging topics in the field of geotechnical engineering. The use of finite element techniques is considered to be a promising method to solve settlement and heave problems, which are associated ... Keywords: FEM, constitutive modelling, finite element method, geotechnical engineering, mechanical behaviour, shallow foundation, shallow foundations, soil behaviour, suction variation, unsaturated soils

Ayman A. Abed; Pieter A. Vermeer

2009-01-01T23:59:59.000Z

28

Temporal Damping Effect of the Yucca Mountain Fractured Unsaturated Rock on Transient Infiltration Pulses  

E-Print Network (OSTI)

unsaturated zone at Yucca Mountain. J. of Cont. Hydrol. ,2003b. Calibration of Yucca Mountain unsaturated zone flowthe unsaturated zone, Yucca Mountain, USGS Water Resources

Zhang, Keni; Wu, Yu-Shu; Pan, Lehua

2005-01-01T23:59:59.000Z

29

Ground Movement in SSRL Ring  

Science Conference Proceedings (OSTI)

Users of the Stanford Synchrotron Radiation Lightsource (SSRL) are being affected by diurnal motion of the synchrotron's storage ring, which undergoes structural changes due to outdoor temperature fluctuations. In order to minimize the effects of diurnal temperature fluctuations, especially on the vertical motion of the ring floor, scientists at SSRL tried three approaches: painting the storage ring white, covering the asphalt in the middle of the ring with highly reflective Mylar and installing Mylar on a portion of the ring roof and walls. Vertical motion in the storage ring is measured by a Hydrostatic Leveling System (HLS), which calculates the relative height of water in a pipe that extends around the ring. The 24-hr amplitude of the floor motion was determined using spectral analysis of HLS data, and the ratio of this amplitude before and after each experiment was used to quantitatively determine the efficacy of each approach. The results of this analysis showed that the Mylar did not have any significant effect on floor motion, although the whitewash project did yield a reduction in overall HLS variation of 15 percent. However, further analysis showed that the reduction can largely be attributed to a few local changes rather than an overall reduction in floor motion around the ring. Future work will consist of identifying and selectively insulating these local regions in order to find the driving force behind diurnal floor motion in the storage ring.

Sunikumar, Nikita; /UCLA /SLAC

2011-08-25T23:59:59.000Z

30

Optical fiber having wave-guiding rings  

DOE Patents (OSTI)

A waveguide includes a cladding region that has a refractive index that is substantially uniform and surrounds a wave-guiding region that has an average index that is close to the index of the cladding. The wave-guiding region also contains a thin ring or series of rings that have an index or indices that differ significantly from the index of the cladding. The ring or rings enable the structure to guide light.

Messerly, Michael J. (Danville, CA); Dawson, Jay W. (Livermore, CA); Beach, Raymond J. (Livermore, CA); Barty, Christopher P. J. (Hayward, CA)

2011-03-15T23:59:59.000Z

31

Behavior of spent fuel under unsaturated conditions  

Science Conference Proceedings (OSTI)

To evaluate the performance of spent fuel in the potential repository at Yucca Mountain, Nevada, spent fuel fragments are being exposed to small and intermittent amounts of simulated groundwater under unsaturated conditions. Both the leachate and the visual appearance of the spent fuel have been characterized for 581 days of testing. The amount of Am and Cm measured in the leachates was one to two orders of magnitude greater than that released from spent fuel under saturated conditions. The cause of this difference has not been firmly identified but may be attributable to the presence of large amounts of actinide-containing colloids in the leachate of the unsaturated tests.

Finn, P.A.; Hoh, J.C.; Bates, J.K.; Wolf, S.F. [Argonne National Lab., IL (United States). Chemical Technology Div.

1994-12-31T23:59:59.000Z

32

A Conductivity Relationship for Steady-state Unsaturated Flow Processes under Optimal Flow Conditions  

SciTech Connect

Optimality principles have been used for investigating physical processes in different areas. This work attempts to apply an optimal principle (that water flow resistance is minimized on global scale) to steady-state unsaturated flow processes. Based on the calculus of variations, we show that under optimal conditions, hydraulic conductivity for steady-state unsaturated flow is proportional to a power function of the magnitude of water flux. This relationship is consistent with an intuitive expectation that for an optimal water flow system, locations where relatively large water fluxes occur should correspond to relatively small resistance (or large conductance). Similar results were also obtained for hydraulic structures in river basins and tree leaves, as reported in other studies. Consistence of this theoretical result with observed fingering-flow behavior in unsaturated soils and an existing model is also demonstrated.

Liu, H. H.

2010-09-15T23:59:59.000Z

33

Lithium Ion Solvation: Amine and Unsaturated Hydrocarbon Solvates of Lithium Hexamethyldisilazide (LiHMDS)  

E-Print Network (OSTI)

Lithium Ion Solvation: Amine and Unsaturated Hydrocarbon Solvates of Lithium Hexamethyldisilazide, and 13C NMR spectroscopic studies of 6Li-15N labeled lithium hexamethyldisilazide ([6Li,15N]- Li ligand structure and lithium amide aggregation state is a complex and sensitive function of amine alkyl

Collum, David B.

34

Oxidative dehydrogenation of alkanes to unsaturated hydrocarbons  

DOE Patents (OSTI)

Oxidative dehydrogenation of alkanes to unsaturated hydrocarbons is carried out over metal vanadate catalysts under oxidizing conditions. The vanadate catalysts are represented by the formulas M[sub 3](VO[sub 4])[sub 2] and MV[sub 2]O[sub 6], M representing Mg, Zn, Ca, Pb, or Cd. The reaction is carried out in the presence of oxygen, but the formation of oxygenate by-products is suppressed.

Kung, H.H.; Chaar, M.A.

1988-10-11T23:59:59.000Z

35

Algebra structure on the Hochschild cohomology of the ring of invariants of a Weyl algebra under a finite group.  

E-Print Network (OSTI)

Let $A_n$ be the $n$-th Weyl algebra, and let $G\\subset\\Sp_{2n}(\\C)\\subset\\Aut(A_n)$ be a finite group of linear automorphisms of $A_n$. In this paper we compute the multiplicative structure on the Hochschild cohomology $\\HH^*(A_n^G)$ of the algebra of invariants of $G$. We prove that, as a graded algebra, $\\HH^*(A_n^G)$ is isomorphic to the graded algebra associated to the center of the group algebra $\\C G$ with respect to a filtration defined in terms of the defining representation of $G$.

Mariano Suarez-Alvarez.; pp. 291--306.

36

Stirling engine piston ring  

DOE Patents (OSTI)

A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

Howarth, Roy B. (Clifton Park, NY)

1983-01-01T23:59:59.000Z

37

Stirling engine piston ring  

SciTech Connect

A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

Howarth, Roy B. (Clifton Park, NY)

1983-01-01T23:59:59.000Z

38

A Mountain-Scale Thermal Hydrologic Model for Simulating Fluid Flow and Heat Transfer in Unsaturated Fractured Rock  

E-Print Network (OSTI)

Studies Using the Yucca Mountain Unsaturated Zone Model,Unsaturated Zone at Yucca Mountain, Nevada, to Thermal LoadUnsaturated Zone, Yucca Mountain, Nevada, Water-Resources

Wu, Yu-Shu; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, Gudmundur S.

2005-01-01T23:59:59.000Z

39

Hydraulic properties of adsorbed water films in unsaturated porous media  

E-Print Network (OSTI)

ionic strength and unit hydraulic head gradient. Figure 7.of the unsaturated hydraulic conductivity on matricYork. Durner, W. (1994), Hydraulic conductivity estimation

Tokunaga, Tetsu K.

2009-01-01T23:59:59.000Z

40

Characterizing unsaturated diffusion in porous tuff gravel  

SciTech Connect

Evaluation of solute diffusion in unsaturated porous gravel is very important for investigations of contaminant transport and remediation, risk assessment, and waste disposal (for example, the potential high-level nuclear waste repository at Yucca Mountain, Nevada). For a porous aggregate medium such as granular tuff, the total water content is comprised of surface water and interior water. The surface water component (water film around grains and pendular water between the grain contacts) could serve as a predominant diffusion pathway. To investigate the extent to which surface water films and contact points affect solute diffusion in unsaturated gravel, we examined the configuration of water using x-ray computed tomography in partially saturated gravel, and made quantitative measurements of diffusion at multiple water contents using two different techniques. In the first, diffusion coefficients of potassium chloride in 2-4 mm granular tuff at multiple water contents were calculated from electrical conductivity measurements using the Nernst-Einstein equation. In the second, we used laser ablation with inductively coupled plasma-mass spectrometry to perform micro-scale mapping, allowing the measurement of diffusion coefficients for a mixture of chemical tracers for tuff cubes and tetrahedrons having two contact geometries (cube-cube and cube-tetrahedron). The x-ray computed tomography images show limited contact between grains, and this could hinder the pathways for diffusive transport. Experimental results show the critical role of surface water in controlling transport pathways and hence the magnitude of diffusion. Even with a bulk volumetric water content of 1.5%, the measured solute diffusion coefficient is as low as 1.5 x 10{sup -14} m{sup 2}/s for tuff gravel. Currently used diffusion models relating diffusion coefficients to total volumetric water content inadequately describe unsaturated diffusion behavior in porous gravel at very low water contents.

Hu, Qinhong; Kneafsey, Timothy J.; Roberts, Jeffery J.; Tomutsa, Liviu; Wang, Joseph, S.Y.

2003-11-12T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Review and selection of unsaturated flow models  

SciTech Connect

Since the 1960`s, ground-water flow models have been used for analysis of water resources problems. In the 1970`s, emphasis began to shift to analysis of waste management problems. This shift in emphasis was largely brought about by site selection activities for geologic repositories for disposal of high-level radioactive wastes. Model development during the 1970`s and well into the 1980`s focused primarily on saturated ground-water flow because geologic repositories in salt, basalt, granite, shale, and tuff were envisioned to be below the water table. Selection of the unsaturated zone at Yucca Mountain, Nevada, for potential disposal of waste began to shift model development toward unsaturated flow models. Under the US Department of Energy (DOE), the Civilian Radioactive Waste Management System Management and Operating Contractor (CRWMS M&O) has the responsibility to review, evaluate, and document existing computer models; to conduct performance assessments; and to develop performance assessment models, where necessary. This document describes the CRWMS M&O approach to model review and evaluation (Chapter 2), and the requirements for unsaturated flow models which are the bases for selection from among the current models (Chapter 3). Chapter 4 identifies existing models, and their characteristics. Through a detailed examination of characteristics, Chapter 5 presents the selection of models for testing. Chapter 6 discusses the testing and verification of selected models. Chapters 7 and 8 give conclusions and make recommendations, respectively. Chapter 9 records the major references for each of the models reviewed. Appendix A, a collection of technical reviews for each model, contains a more complete list of references. Finally, Appendix B characterizes the problems used for model testing.

Reeves, M.; Baker, N.A.; Duguid, J.O. [INTERA, Inc., Las Vegas, NV (United States)

1994-04-04T23:59:59.000Z

42

Two Dimensional Polyamides Prepared From Unsaturated Carboxylic Acids And Amines.  

DOE Patents (OSTI)

A polyamide and a process for preparing the polyamide are disclosed. The process comprises reacting in a reaction mixture a monomer selected from unsaturated carboxylic acids, esters of unsaturated carboxylic acids, anhydrides of unsaturated carboxylic acids, and mixtures thereof, and a first amine to form an intermediate reaction product in the reaction mixture, wherein the first amine is selected from RR.sub.1 NH, RNH.sub.2, RR.sub.1 NH.sub.2.sup.+, RNH.sub.3.sup.+ and mixtures thereof, wherein R and R.sub.1 can be the same or different and each contain between about 1 and 50 carbon atoms and are optionally substituted with heteroatoms oxygen, nitrogen, sulfur, and phosphorus and combinations thereof, and reacting the intermediate reaction product and a second amine to form a polyamide, wherein the second amine is selected from R.sub.2 R.sub.3 NH, R.sub.2 NH.sub.2, R.sub.2 R.sub.3 NH.sub.2.sup.+, R.sub.2 NH.sub.3.sup.+ and mixtures thereof wherein R.sub.2 and R.sub.3 can be the same or different and each contain between about 1 and 50 carbon atoms and are optionally substituted with heteroatoms oxygen, nitrogen, sulfur, and phosphorus and combinations thereof, wherein multiple of the R, R.sub.1, R.sub.2, and R.sub.3 are in vertically aligned spaced relationship along a backbone formed by the polyamide. In one version of the invention, the monomer is selected from maleic anhydride, maleic acid esters, and mixtures thereof. In another version of the invention, the first amine is an alkylamine, such as tetradecylamine, and the second amine is a polyalkylene polyamine, such as pentaethylenehexamine. In yet another version of the invention, the first amine and the second amine are olefinic or acetylenic amines, such as the reaction products of an alkyldiamine and an acetylenic carboxylic acid. The first amine and the second amine may be the same or different depending on the desired polyamide polymer structure.

McDonald, William F. (Utica, OH); Huang, Zhi Heng (East Lansing, MI); Wright, Stacy C. (Lansing, MI); Danzig, Morris (Northbrook, IL); Taylor, Andrew C. (Ann Arbor, MI)

2002-07-17T23:59:59.000Z

43

NaturAnalogs for the Unsaturated Zone  

Science Conference Proceedings (OSTI)

The purpose of this Analysis/Model Report (AMR) is to document natural and anthropogenic (human-induced) analog sites and processes that are applicable to flow and transport processes expected to occur at the potential Yucca Mountain repository in order to build increased confidence in modeling processes of Unsaturated Zone (UZ) flow and transport. This AMR was prepared in accordance with ''AMR Development Plan for U0135, Natural Analogs for the UZ'' (CRWMS 1999a). Knowledge from analog sites and processes is used as corroborating information to test and build confidence in flow and transport models of Yucca Mountain, Nevada. This AMR supports the Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR) and the Yucca Mountain Site Description. The objectives of this AMR are to test and build confidence in the representation of UZ processes in numerical models utilized in the UZ Flow and Transport Model. This is accomplished by: (1) applying data from Boxy Canyon, Idaho in simulations of UZ flow using the same methodologies incorporated in the Yucca Mountain UZ Flow and Transport Model to assess the fracture-matrix interaction conceptual model; (2) Providing a preliminary basis for analysis of radionuclide transport at Pena Blanca, Mexico as an analog of radionuclide transport at Yucca Mountain; and (3) Synthesizing existing information from natural analog studies to provide corroborating evidence for representation of ambient and thermally coupled UZ flow and transport processes in the UZ Model.

A. Simmons; A. Unger; M. Murrell

2000-03-08T23:59:59.000Z

44

Unsaturated hydraulic parameters determined from direct and indirect methods  

SciTech Connect

Hydraulic parameters are required for numerical simulations of unsaturated flow at Yucca Mountain, a vertically heterogeneous volcanic site for a potential high-level waste repository in the desert southwest. In this paper, direct measurements of the unsaturated hydraulic conductivity using a centrifuge with a specialized rotor are compared to those estimated using a predictive conductivity equation and two methods of measuring moisture retention.

Flint, Lorraine E.; Hudson, David B.; Flint, Alan L.

1997-10-22T23:59:59.000Z

45

Modeling studies of mountain-scale radionuclide transport in the unsaturated zone at Yucca Mountain, Nevada  

E-Print Network (OSTI)

Investigations at Yucca Mountain - The Potential Repositoryin the Unsaturated Zone, Yucca Mountain, Nevada, ResourcesIN THE UNSATURATED ZONE AT YUCCA MOUNTAIN, NEVADA George J.

Moridis, George J.; Seol, Yongkoo; Wu, Yu-Shu

2003-01-01T23:59:59.000Z

46

Ring-tailed Cat  

NLE Websites -- All DOE Office Websites (Extended Search)

Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Ring-tailed Cat Name: Kenneth Location: NA Country: NA Date: NA Question: I have seen a ring tailed...

47

Gulf Stream Ring Trajectories  

Science Conference Proceedings (OSTI)

During the period 1976–78, the movement of 14 Gulf Stream rings, including two anticyclonic and 12 cyclonic rings, was measured with satellite-tracked free-drifting buoys. The buoys in the cyclonic rings showed a tendency to move out toward the ...

Philip L. Richardson

1980-01-01T23:59:59.000Z

48

The Dynamics of Barotropically Dominated Rings  

Science Conference Proceedings (OSTI)

Based on observations, the proposition is forwarded that some rings involve important deep flow. The work described herein is directed at understanding the consequences on eddy evolution of such structure. An analysis of the equations of motion ...

William K. Dewar; Christine Gailliard

1994-01-01T23:59:59.000Z

49

A security-centric ring-based software architecture  

Science Conference Proceedings (OSTI)

Software architectures that are centered on security historically contain layers to implement security controls, with the layered structure tending towards a series of rings. John Warden devised a five-ring model to assess enemy systems for strategic ... Keywords: Warden's five-ring model, computer security, software architecture

Jay-Evan J. Tevis; John A. Hamilton, Jr.

2007-03-01T23:59:59.000Z

50

Approaches to large scale unsaturated flow in heterogeneous, stratified, and fractured geologic media  

Science Conference Proceedings (OSTI)

This report develops a broad review and assessment of quantitative modeling approaches and data requirements for large-scale subsurface flow in radioactive waste geologic repository. The data review includes discussions of controlled field experiments, existing contamination sites, and site-specific hydrogeologic conditions at Yucca Mountain. Local-scale constitutive models for the unsaturated hydrodynamic properties of geologic media are analyzed, with particular emphasis on the effect of structural characteristics of the medium. The report further reviews and analyzes large-scale hydrogeologic spatial variability from aquifer data, unsaturated soil data, and fracture network data gathered from the literature. Finally, various modeling strategies toward large-scale flow simulations are assessed, including direct high-resolution simulation, and coarse-scale simulation based on auxiliary hydrodynamic models such as single equivalent continuum and dual-porosity continuum. The roles of anisotropy, fracturing, and broad-band spatial variability are emphasized. 252 refs.

Ababou, R.

1991-08-01T23:59:59.000Z

51

Effects of dry fractures on matrix diffusion in unsaturated fractured rocks  

E-Print Network (OSTI)

Symposium on Multiphase Transport in Porous Media, ASMEmultiphase heat and mass flow in unsaturated fractured porous

Seol, Yongkoo; Liu, Hui Hai; Bodvarsson, Gudmundur S.

2002-01-01T23:59:59.000Z

52

Brane World Black Rings  

E-Print Network (OSTI)

Five dimensional neutral rotating black rings are described from a Randall-Sundrum brane world perspective in the bulk black string framework. To this end we consider a rotating black string extension of a five dimensional black ring into the bulk of a six dimensional Randall-Sundrum brane world with a single four brane. The bulk solution intercepts the four brane in a five dimensional black ring with the usual curvature singularity on the brane. The bulk geodesics restricted to the plane of rotation of the black ring are constructed and their projections on the four brane match with the usual black ring geodesics restricted to the same plane. The asymptotic nature of the bulk geodesics are elucidated with reference to a bulk singularity at the AdS horizon. We further discuss the description of a brane world black ring as a limit of a boosted bulk black 2 brane with periodic identification.

Anurag Sahay; Gautam Sengupta

2007-04-09T23:59:59.000Z

53

Wind turbine ring/shroud drive system - Energy Innovation Portal  

A wind turbine capable of driving multiple electric generators having a ring or shroud structure for reducing blade root bending moments, hub loads, blade fastener ...

54

Temperature and Humidity Profiles in Mesoscale Unsaturated Downdrafts  

Science Conference Proceedings (OSTI)

Profiles of temperature and humidity beneath precipitating anvil clouds in tropical convective systems suggest the presence of a mesoscale unsaturated downdraft there. In this paper, a one-dimensional, steady-state, hydrostatic model of a ...

Colleen A. Leary

1980-05-01T23:59:59.000Z

55

Proving Ring Patent  

Science Conference Proceedings (OSTI)

Whittemore and Petrenko submitted a patent for their proving ring, number 1648375, to the United States Patent Office on September 14, 1926. ...

2011-10-03T23:59:59.000Z

56

Concentric Black Rings  

E-Print Network (OSTI)

We present new supersymmetric solutions of five-dimensional minimal supergravity that describe concentric black rings with an optional black hole at the common centre. Configurations of two black rings are found which have the same conserved charges as a single rotating black hole; these black rings can have a total horizon area less than, equal to, or greater than the black hole with the same charges. A numerical investigation of these particular black ring solutions suggests that they do not have closed timelike curves.

Jerome P. Gauntlett; Jan B. Gutowski

2004-08-02T23:59:59.000Z

57

Optimality and Conductivity for Water Flow: From Landscapes, to Unsaturated Soils, to Plant Leaves  

Science Conference Proceedings (OSTI)

Optimality principles have been widely used in many areas. Based on an optimality principle that any flow field will tend toward a minimum in the energy dissipation rate, this work shows that there exists a unified form of conductivity relationship for three different flow systems: landscapes, unsaturated soils and plant leaves. The conductivity, the ratio of water flux to energy gradient, is a power function of water flux although the power value is system dependent. This relationship indicates that to minimize energy dissipation rate for a whole system, water flow has a small resistance (or a large conductivity) at a location of large water flux. Empirical evidence supports validity of the relationship for landscape and unsaturated soils (under gravity dominated conditions). Numerical simulation results also show that the relationship can capture the key features of hydraulic structure for a plant leaf, although more studies are needed to further confirm its validity. Especially, it is of interest that according to this relationship, hydraulic conductivity for gravity-dominated unsaturated flow, unlike that defined in the classic theories, depends on not only capillary pressure (or saturation), but also the water flux. Use of the optimality principle allows for determining useful results that are applicable to a broad range of areas involving highly non-linear processes and may not be possible to obtain from classic theories describing water flow processes.

Liu, H.H.

2012-02-23T23:59:59.000Z

58

Boundary integral methods for unsaturated flow  

Science Conference Proceedings (OSTI)

Many large simulations may be required to assess the performance of Yucca Mountain as a possible site for the nations first high level nuclear waste repository. A boundary integral equation method (BIEM) is described for numerical analysis of quasilinear steady unsaturated flow in homogeneous material. The applicability of the exponential model for the dependence of hydraulic conductivity on pressure head is discussed briefly. This constitutive assumption is at the heart of the quasilinear transformation. Materials which display a wide distribution in pore-size are described reasonably well by the exponential. For materials with a narrow range in pore-size, the exponential is suitable over more limited ranges in pressure head. The numerical implementation of the BIEM is used to investigate the infiltration from a strip source to a water table. The net infiltration of moisture into a finite-depth layer is well-described by results for a semi-infinite layer if {alpha}D > 4, where {alpha} is the sorptive number and D is the depth to the water table. the distribution of moisture exhibits a similar dependence on {alpha}D. 11 refs., 4 figs.,

Martinez, M.J.; McTigue, D.F.

1990-12-31T23:59:59.000Z

59

Factors affecting piston ring friction  

E-Print Network (OSTI)

The piston ring pack friction is a major contributor to the internal combustion engine mechanical friction loss. The oil control ring decides the oil supply to the top two rings in addition to being the major friction ...

Liao, Kai, Ph. D. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

60

Self-certified ring signatures  

Science Conference Proceedings (OSTI)

We present a new notion, Self-certified Ring Signature (SCRS), to provide an alternative solution to the certificate management problem in ring signatures and eliminate private key escrow problem in identity based ring signatures. Our scheme captures ...

Nan Li; Yi Mu; Willy Susilo; Fuchun Guo

2011-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Hydraulic properties of adsorbed water films in unsaturated porous media  

SciTech Connect

Adsorbed water films strongly influence residual water saturations and hydraulic conductivities in porous media at low saturations. Hydraulic properties of adsorbed water films in unsaturated porous media were investigated through combining Langmuir's film model with scaling analysis, without use of any adjustable parameters. Diffuse double layer influences are predicted to be important through the strong dependence of adsorbed water film thickness (f) on matric potential ({Psi}) and ion charge (z). Film thickness, film velocity, and unsaturated hydraulic conductivity are predicted to vary with z{sup -1}, z{sup -2}, and z{sup -3}, respectively. In monodisperse granular media, the characteristic grain size ({lambda}) controls film hydraulics through {lambda}{sup -1} scaling of (1) the perimeter length per unit cross sectional area over which films occur, (2) the critical matric potential ({Psi}{sub c}) below which films control flow, and (3) the magnitude of the unsaturated hydraulic conductivity when {Psi} < {Psi}{sub c}. While it is recognized that finer textured sediments have higher unsaturated hydraulic conductivities than coarser sands at intermediate {Psi}, the {lambda}{sup -1} scaling of hydraulic conductivity predicted here extends this understanding to very low saturations where all pores are drained. Extremely low unsaturated hydraulic conductivities are predicted under adsorbed film-controlled conditions (generally < 0.1 mm y{sup -1}). On flat surfaces, the film hydraulic diffusivity is shown to be constant (invariant with respect to {Psi}).

Tokunaga, Tetsu K.

2009-03-01T23:59:59.000Z

62

Repository site data report for unsaturated tuff, Yucca Mountain, Nevada  

Science Conference Proceedings (OSTI)

The US Department of Energy is currently considering the thick sequences of unsaturated, fractured tuff at Yucca Mountain, on the southwestern boundary of the Nevada Test Site, as a possible candidate host rock for a nuclear-waste repository. Yucca Mountain is in one of the most arid areas in the United States. The site is within the south-central part of the Great Basin section of the Basin and Range physiographic province and is located near a number of silicic calderas of Tertiary age. Although localized zones of seismic activity are common throughout the province, and faults are present at Yucca Mountain, the site itself is basically aseismic. No data are available on the composition of ground water in the unsaturated zone at Yucca Mountain. It has been suggested that the composition is bounded by the compositions of water from wells USW-H3, UE25p-1, J-13, and snow or rain. There are relatively few data available from Yucca Mountain on the moisture content and saturation, hydraulic conductivity, and characteristic curves of the unsaturated zone. The available literature on thermomechanical properties of tuff does not always distinguish between data from the saturated zone and data from the unsaturated zone. Geochemical, hydrologic, and thermomechanical data available on the unsaturated tuffs of Yucca Mountain are tabulated in this report. Where the data are very sparse, they have been supplemented by data from the saturated zone or from areas other than Yucca Mountain. 316 refs., 58 figs., 37 tabs.

Tien, P.L.; Updegraff, C.D.; Siegel, M.D.; Wahi, K.K.; Guzowski, R.V.

1985-11-01T23:59:59.000Z

63

Storage Ring Parameters  

NLE Websites -- All DOE Office Websites (Extended Search)

Photon Source Parameters Storage Ring Parameters Print General Parameters Parameter Value Beam particle electron Beam energy 1.9 GeV (1.0-1.9 GeV possible) Injection energy 1.9 GeV...

64

Method and apparatus for measuring coupled flow, transport, and reaction processes under liquid unsaturated flow conditions  

DOE Patents (OSTI)

The present invention is a method and apparatus for measuring coupled flow, transport and reaction processes under liquid unsaturated flow conditions. The method and apparatus of the present invention permit distinguishing individual precipitation events and their effect on dissolution behavior isolated to the specific event. The present invention is especially useful for dynamically measuring hydraulic parameters when a chemical reaction occurs between a particulate material and either liquid or gas (e.g. air) or both, causing precipitation that changes the pore structure of the test material.

McGrail, Bernard P. (Pasco, WA); Martin, Paul F. (Richland, WA); Lindenmeier, Clark W. (Richland, WA)

1999-01-01T23:59:59.000Z

65

RFOFO RING COOLER.  

DOE Green Energy (OSTI)

This note describes the design of an ionization cooling ring that uses an alternating polarity solenoid lattice. The ring is approximately 33 m in circumference and has 12 cells. Each cell has two opposing focusing solenoids placed either side of a hydrogen wedge absorber. The solenoid coils are located outside pillbox rf cavities. Bending is provided by tipping the solenoid coils. The simulated merit factor ({approx} the increase in 6D phase space density) is 81.

BERG,J.S.FERNOW,R.C.PALMER,R.B.

2002-07-01T23:59:59.000Z

66

Revisiting the thermodynamics of hardening plasticity for unsaturated soils  

E-Print Network (OSTI)

A thermodynamically consistent extension of the constitutive equations of saturated soils to unsaturated conditions is often worked out through the use a unique 'effective' interstitial pressure, accounting equivalently for the pressures of the saturating fluids acting separately on the internal solid walls of the pore network. The natural candidate for this effective interstitial pressure is the space averaged interstitial pressure. In contrast experimental observations have revealed that, at least, a pair of stress state variables was needed for a suitable framework to describe stress-strain-strength behaviour of unsaturated soils. The thermodynamics analysis presented here shows that the most general approach to the behaviour of unsaturated soils actually requires three stress state variables: the suction, which is required to describe the invasion of the soil by the liquid water phase through the retention curve; two effective stresses, which are required to describe the soil deformation at water saturati...

Coussy, Olivier; Vaunat, Jean; 10.1016/j.compgeo.2009.09.003

2010-01-01T23:59:59.000Z

67

Numerical evaluation of effective unsaturated hydraulic properties for fractured rocks  

Science Conference Proceedings (OSTI)

To represent a heterogeneous unsaturated fractured rock by its homogeneous equivalent, Monte Carlo simulations are used to obtain upscaled (effective) flow properties. In this study, we present a numerical procedure for upscaling the van Genuchten parameters of unsaturated fractured rocks by conducting Monte Carlo simulations of the unsaturated flow in a domain under gravity-dominated regime. The simulation domain can be chosen as the scale of block size in the field-scale modeling. The effective conductivity is computed from the steady-state flux at the lower boundary and plotted as a function of the averaging pressure head or saturation over the domain. The scatter plot is then fitted using van Genuchten model and three parameters, i.e., the saturated conductivity K{sub s}, the air-entry parameter {alpha}, the pore-size distribution parameter n, corresponding to this model are considered as the effective K{sub s}, effective {alpha}, and effective n, respectively.

Lu, Zhiming [Los Alamos National Laboratory; Kwicklis, Edward M [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

68

A site scale model for modeling unsaturated zone processes at Yucca Mountain, Nevada  

E-Print Network (OSTI)

Unsaturated Zone Model of Yucca Mountain, Nevada, for theZone Trocesses at yucca Mountain, N G. S. Bodvarsson, Y. S.unsaturated zone at Yucca Mountain, Nevada, as a permanent

1997-01-01T23:59:59.000Z

69

A mountain-scale model for characterizing unsaturated flow and transport in fractured tuffs of Yucca Mountain  

E-Print Network (OSTI)

to Fault Zones at Yucca Mountain, Nevada, International2003c. Calibration of Yucca Mountain Unsaturated Zone FlowUnsaturated Zone, Yucca Mountain, Nevada, Water-Resources

Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Bodvarsson, G.S.

2003-01-01T23:59:59.000Z

70

The Influence of Proposed Repository Thermal Load on Multiphase Flow and Heat Transfer in the Unsaturated Zone of Yucca Mountain  

E-Print Network (OSTI)

Studies Using the Yucca Mountain Unsaturated Zone Model,Unsaturated Zone at Yucca Mountain, Nevada, to Thermal LoadLarge Block Test at Yucca Mountain, Nevada, Water Resources

Wu, Y.-S.; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, G.S.

2006-01-01T23:59:59.000Z

71

Modeling thermal-hydrological response of the unsaturated zone at Yucca Mountain, Nevada, to thermal load at a potential repository  

E-Print Network (OSTI)

Repository at Yucca Mountain. In Materials Research Societystudies using the Yucca Mountain unsaturated zone model.Unsaturated Zone, Yucca Mountain, Nevada. Water Resources

Haukwa, C.B.; Wu, Yu-Shu; Bodvarsson, G.S.

2002-01-01T23:59:59.000Z

72

Thermodynamic black di-rings  

SciTech Connect

Previously the five dimensional S{sup 1}-rotating black rings have been superposed in a concentric way by some solitonic methods, and regular systems of two S{sup 1}-rotating black rings were constructed by the authors and then Evslin and Krishnan (we called these solutions 'black di-rings'). In this place we show some characteristics of the solutions of five dimensional black di-rings, especially in thermodynamic equilibrium. After the summary of the di-ring expressions and their physical quantities, first we comment on the equivalence of the two different solution sets of the black di-rings. Then the existence of thermodynamic black di-rings is shown, in which both isothermality and isorotation between the inner black ring and the outer black ring are realized. We also give detailed analysis of peculiar properties of the thermodynamic black di-ring including discussion about a certain kind of thermodynamic stability (instability) of the system.

Iguchi, Hideo; Mishima, Takashi [Laboratory of Physics, College of Science and Technology, Nihon University, Narashinodai, Funabashi, Chiba 274-8501 (Japan)

2010-10-15T23:59:59.000Z

73

Thermodynamic black di-rings  

E-Print Network (OSTI)

Previously the five dimensional $S^1$-rotating black rings have been superposed in concentric way by some solitonic methods and regular systems of two $S^1$-rotating black rings were constructed by the authors and then Evslin and Krishnan (we called these solutions black di-rings). In this place we show some characteristics of the solutions of five dimensional black di-rings, especially in thermodynamic equilibrium. After the summary of the di-ring expressions and their physical quantities, first we comment on the equivalence of the two different solution-sets of the black di-rings. Then the existence of thermodynamic black di-rings are shown, in which both iso-thermality and iso-rotation between the inner black ring and the outer black ring are realized. We also give detailed analysis of peculiar properties of the thermodynamic black di-ring including discussion about a certain kind of thermodynamic stability (instability) of the system.

Iguchi, Hideo

2010-01-01T23:59:59.000Z

74

Storage Ring Operation Modes  

NLE Websites -- All DOE Office Websites (Extended Search)

Longitudinal bunch profile and Up: APS Storage Ring Parameters Longitudinal bunch profile and Up: APS Storage Ring Parameters Previous: Source Parameter Table Storage Ring Operation Modes Standard Operating Mode, top-up Fill pattern: 102 mA in 24 singlets (single bunches) with a nominal current of 4.25 mA and a spacing of 153 nanoseconds between singlets. Lattice configuration: Low emittance lattice with effective emittance of 3.1 nm-rad and coupling of 1%. Bunch length (rms): 33.5 ps. Refill schedule: Continuous top-up with single injection pulses occurring at a minimum of two minute intervals, or a multiple of two minute intervals. Special Operating Mode - 324 bunches, non top-up Fill pattern: 102 mA in 324 uniformly spaced singlets with a nominal single bunch current of 0.31 mA and a spacing of 11.37 nanoseconds between singlets.

75

NSLS VUV Storage Ring  

NLE Websites -- All DOE Office Websites (Extended Search)

VUV Storage Ring VUV Storage Ring VUV Normal Operations Operating Parameters (pdf) Insertion Devices Flux & Brightness Orbit Stability Lattice Information (pdf) Lattice : MAD Dataset Mechanical Drawing (pdf) VUV Operating Schedule Introduction & History The VUV Ring at the National Synchrotron Light Source was one of the first of the 2nd generation light sources to operate in the world. Initially designed in 1976 the final lattice design was completed in 1978 shortly after funding was approved. Construction started at the beginning of FY 1979 and installation of the magnets was well underway by the end of FY 1980. The first stored beam was achieved in December of 1981 at 600 MeV and the first photons were delivered to beamlines in May 1982, with routine beam line operations underway by the start of FY 1983. The number of beam

76

Stochastic analysis of unsaturated flow with probabilistic collocation method  

E-Print Network (OSTI)

with probabilistic collocation method, Water Resour. Res., 45, W08425, doi:10.1029/2008WR007530. 1. Introduction [2, the vadose zone has received increasing attention in recent years. Because of the coexis- tence of water to study the effect of spatial variability on flow in unsaturated zone [Jury, 1982; Yeh et al., 1985a, 1985

Lu, Zhiming

77

Heat and mass transfer in unsaturated porous media. Final report  

DOE Green Energy (OSTI)

A preliminary study of heat and water transport in unsaturated porous media is reported. The project provides background information regarding the feasibility of seasonal thermal energy storage in unconfined aquifers. A parametric analysis of the factors of importance, and an annotated bibliography of research findings pertinent to unconfined aquifer thermal energy storage (ATES) are presented. This analysis shows that heat and mass transfer of water vapor assume dominant importance in unsaturated porous media at elevated temperature. Although water vapor fluxes are seldom as large as saturated medium liquid water fluxes, they are important under unsaturated conditions. The major heat transport mechanism for unsaturated porous media at temperatures from 50 to 90/sup 0/C is latent heat flux. The mechanism is nonexistent under saturated conditions but may well control design of unconfined aquifer storage systems. The parametric analysis treats detailed physical phenomena which occur in the flow systems study and demonstrates the temperature and moisture dependence of the transport coefficients of importance. The question of design of an unconfined ATES site is also addressed by considering the effects of aquifer temperature, depth to water table, porous medium flow properties, and surface boundary conditions. Recommendations are made for continuation of this project in its second phase. Both scientific and engineering goals are considered and alternatives are presented.

Childs, S.W.; Malstaff, G.

1982-02-01T23:59:59.000Z

78

Unidirectional ring lasers  

DOE Patents (OSTI)

Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity is disclosed. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction. 21 figs.

Hohimer, J.P.; Craft, D.C.

1994-09-20T23:59:59.000Z

79

Field reversed ion rings  

DOE Green Energy (OSTI)

In typical field-reversed ion ring experiments, an intense annular ion beam is injected across a plasma-filled magnetic cusp region into a neutral gas immersed in a ramped solenoidal magnetic field. Assuming the characteristic ionization time is much shorter than the long ({ital t}{approx_gt}2{pi}/{Omega}{sub {ital i}}) beam evolution time scale, we investigate the formation of an ion ring in the background plasma followed by field reversal, using a 21/2-D hybrid, PIC code FIRE, in which the beam and background ions are treated as particles and the electrons as a massless fluid. We show that beam bunching and trapping occurs downstream in a ramped magnetic field for an appropriate set of experimental parameters. We find that a compact ion ring is formed and a large field reversal {zeta}={delta}{ital B}/{ital B}{approx_gt}1 on axis develops. We also observe significant deceleration of the ring on reflection due to the transfer of its axial momentum to the background ions, which creates favorable trapping conditions. {copyright} {ital 1995 American Institute of Physics.}

Sudan, R.N.; Omelchenko, Y.A. [Laboratory of Plasma Studies, Cornell University, Ithaca, New York 14853 (United States)

1995-09-01T23:59:59.000Z

80

Fusion rings for quantum groups  

E-Print Network (OSTI)

We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from [KS] and give a similar description of the sp(2n)-fusion ring in terms of noncommutative symmetric functions. Moreover we give a presentation of all fusion rings in classical types as quotients of polynomial rings extending known results in special cases. Finally we also compute the fusion rings for type G2.

Henning Haahr Andersen; Catharina Stroppel

2012-12-22T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

HYDROGENATION AND CRACKING OF COAL RELATED FUSED-RING STRUCTURES USING ZnCl2 AND AlCl3 CATALYSTS  

E-Print Network (OSTI)

of Molten Salt Catalysts, Ph.D. Thesis, Department ofUSING ZnC1 2 AND AlC1 3 CATALYSTS Sadie S. Salim (Ph.D.With Metal Halide Catalysts Coal Structure Literature Review

Salim, Sadie S.

2013-01-01T23:59:59.000Z

82

Storage Ring | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

The Electron Storage Ring The 7-GeV electrons are injected into the 1104-m-circumference storage ring, a circle of more than 1,000 electromagnets and associated equipment, located...

83

SNS Ring, Spallation Neutron Source, SNS  

NLE Websites -- All DOE Office Websites (Extended Search)

RING RING Lattice Version 1.0 in MAD structure Version 1.1: SNSRing.v.1.1 | 623_620_00.mad Version 1.2 SNSRing.v.1.2 | 623_620_00.mad Matching example MAD optics outputs UAL compatible input example Schematic (one super-period) and mechanical drawing Diagnostics Impedance budget Magnets List and mechanical parameters Mechanical drawings Magnetic field modeling and measurements Installation and survey Power supplies summary and changes Polarity conventions tech.memo and schematic (A polarity) Magnet assemblies Documentation ASAC review presentations DOE review presentations SNS/BNL tech.notes, conference and journal papers SNS/ORNL papers SNS project documentation Other links SNS ring aperture, collimation and beam losses SNS transfer lines SNS/BNL Accelerator Physics SNS/ORNL Accelerator Physics

84

Ring Sizes and Production Ranges  

Science Conference Proceedings (OSTI)

...each other by sawing or machining. The identical components are usually mirrored so as to place the thinnest wall section at the middle of the rolled ring for ease of parting. Because the ring is then symmetrical about the centerline, such rings can often be rolled from a simple blank and it behaves more...

85

RING ROAD SOUTH CHANCELLOR'S  

E-Print Network (OSTI)

Sciences R5 Aston Webb ­ B Block R6 Aston Webb ­ Great Hall R7 Aston Webb ­ C Block R8 Physics West R9P P 24-h Security R3 RING ROAD SOUTH CHANCELLOR'S COURT CHANCELLOR'S University Centre COURT Sports PitchesSports Pitches South Car Park R21 R17 R18 R22 Main Library R19 R23 R24 R 24 R14 R15 R16 East Gate O

Heinke, Dietmar

86

Ring regenerative laser amplifier  

DOE Patents (OSTI)

This invention consists of an efficient, high gain, compact regenerative amplifier that amplifies a seed pulse of laser energy to produce an amplified pulse of greater energy. The amplifier is useful for amplifying seed pulses having a broad bandwidth or in situations where tunability is necessary. The amplifier has high gain while maintaining high pulse contrast. A seed pulse can be amplified to the saturation fluence while maintaining a high contrast (>10[sup 3]). The regenerative amplifier has an optical cavity in a ring configuration, a gain material positioned in the cavity, a polarization-rotating element positioned in the cavity to rotate the polarization of the pulse upon each pass around the cavity, means for inserting the seed pulse into the cavity, and means for removing the polarization-rotated, amplified pulse from the cavity. In some embodiments, the seed pulse is switched in passively, by a selective polarization, and is switched out after a predetermined number of passes around the ring cavity. This completely passive arrangement avoids possibility of switchout failure, and minimizes the ASE problem. In other embodiments, a selectively actuable switch, such as electro-optic element, may be provided within the ring cavity, to switch-in the seed pulse and switch-out the amplified pulse. The electro-optic element may be actuated with a square wave that has a peak voltage equal to the half-wave voltage of the electro-optic crystal.

Perry, M.D.; Patterson, F.G.

1991-01-01T23:59:59.000Z

87

Ring regenerative laser amplifier  

DOE Patents (OSTI)

This invention consists of an efficient, high gain, compact regenerative amplifier that amplifies a seed pulse of laser energy to produce an amplified pulse of greater energy. The amplifier is useful for amplifying seed pulses having a broad bandwidth or in situations where tunability is necessary. The amplifier has high gain while maintaining high pulse contrast. A seed pulse can be amplified to the saturation fluence while maintaining a high contrast (>10{sup 3}). The regenerative amplifier has an optical cavity in a ring configuration, a gain material positioned in the cavity, a polarization-rotating element positioned in the cavity to rotate the polarization of the pulse upon each pass around the cavity, means for inserting the seed pulse into the cavity, and means for removing the polarization-rotated, amplified pulse from the cavity. In some embodiments, the seed pulse is switched in passively, by a selective polarization, and is switched out after a predetermined number of passes around the ring cavity. This completely passive arrangement avoids possibility of switchout failure, and minimizes the ASE problem. In other embodiments, a selectively actuable switch, such as electro-optic element, may be provided within the ring cavity, to switch-in the seed pulse and switch-out the amplified pulse. The electro-optic element may be actuated with a square wave that has a peak voltage equal to the half-wave voltage of the electro-optic crystal.

Perry, M.D.; Patterson, F.G.

1991-12-31T23:59:59.000Z

88

Precooler Ring Vacuum System  

DOE Green Energy (OSTI)

The precooler vacuum system, as proposed by FNAL, is based on a suitable modification of the existing Electron Cooling Ring System. Because of the magnetic cycle of the bending magnets, distributed ion pumping, as exists in the Electron Cooling Ring, is not applicable. Instead, the proposed pumping will be done with commercial appendage ion pumps mounted approximately every two meters around the circumference of the ring. The loss of effective pumping speed and non-uniformity of system pressure with appendage pumps may not be major considerations but the large number required does effect experimental and analytical equipment placement considerations. There is a distributed pumping technique available which: (1) is not affected by the magnetic cycle of the bending magnets; (2) will provide a minimum of four times the hydrogen pumping speed of the proposed appendage ion pumps; (3) will require no power during pumping after the strip is activated; (4) will provide the heat source for bakeout; (5) is easily replaceable; and (6) can be purchased, installed, and operated at a generous economic advantage over the presently proposed ion pumped system. The pumping technique referred to is non-evaporable gettering with ST101 Zr/Al pumping strip. A technical description of this pumping strip is given on Data Sheet 1 and 2 attached to this report.

Moenich, J.

1980-10-02T23:59:59.000Z

89

A multiphase constitutive modeling framework for unsaturated soil behavior  

E-Print Network (OSTI)

We develop a framework for constitutive modeling of unsaturated soils that has the embedded elements of lower scale grain to grain contacts. Continuum models developed from this framework will possess two different phases idealizing the solid grains and their interactions. As a consequence, two different constitutive relationships, corresponding to the grain to grain contact and bulk behavior, co-exist in a constitutive model and govern the response of the model. To be specific, grain to grain sliding under dry or wet condition is idealized and appears as a simple contact law embedded in a continuum framework. There is no need to define plastic strain, as this quantity naturally emerges at the continuum scale as the consequence of frictional sliding at the lower scale. In addition, the effective stress can be naturally worked out from the grain to grain contact law embedded in the model without being subjected to any interpretation. This, in our opinion, is a closer representation of unsaturated soil behavior, compared to existing continuum approaches that map everything onto a single stress-strain relationship. In this paper, the framework is presented in its simplest form that takes into account sliding on a single orientation. Grain to grain contact law with capillary effects is used for the demonstration of the concept, and the technical details behind it. Generalization of the framework for better representation of unsaturated soil behavior will also be sketched out.

Giang D. Nguyen; Yixiang Gan

2013-10-31T23:59:59.000Z

90

The Evolution and Demise of North Brazil Current Rings  

Science Conference Proceedings (OSTI)

Subsurface float and surface drifter observations illustrate the structure, evolution, and eventual demise of 10 North Brazil Current (NBC) rings as they approached and collided with the Lesser Antilles in the western tropical Atlantic Ocean. ...

David M. Fratantoni; Philip L. Richardson

2006-07-01T23:59:59.000Z

91

Patrick Ring | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Patrick Ring Patrick Ring About Us Patrick Ring - Team Leader, Benefits Continuity Team Patrick Ring is the team leader for the continuity of contractor pension and postretirement benefit programs for contractor workers formerly employed at DOE closure sites. Mr. Ring has more than 31 years of federal service between the U.S. Department of Energy (DOE), U.S. Department of Defense, and the Pension Benefit Guaranty Corporation. His experience has provided him extensive knowledge and experience in dealing with contractor retirement benefit programs. Mr. Ring joined the Office of Legacy Management (LM) in October 2005 as a contractor industrial relations specialist/actuary and a member of the Benefits Continuity Team. Prior to joining LM, Mr. Ring was employed as an actuary with the Defense

92

Optimizing ring-based CSR sources  

E-Print Network (OSTI)

synchrotron radiation from the NSLS VUV ring", NIMA, 463 (of Coherent Emission from the NSLS VUV Ring”, Proc. 1999

2004-01-01T23:59:59.000Z

93

Independence of vectors in codes over rings  

Science Conference Proceedings (OSTI)

We study codes over Frobenius rings. We describe Frobenius rings via an isomorphism to the product of local Frobenius rings and use this decomposition to describe an analog of linear independence. Special attention is given to codes over principal ideal ... Keywords: Chinese Remainder Theorem, Codes over rings, Frobenius rings, Primary 94B05, Principal ideal rings, Secondary 13A99

Steven T. Dougherty; Hongwei Liu

2009-04-01T23:59:59.000Z

94

Ring Ring. Who's There? A Wind Expert | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Ring Ring. Who's There? A Wind Expert Ring Ring. Who's There? A Wind Expert Ring Ring. Who's There? A Wind Expert August 23, 2010 - 10:44am Addthis Stephen Graff Former Writer & editor for Energy Empowers, EERE Have a question about wind energy? You're not alone. In 2009, about 1,200 people- ranging from farmers, teachers, county commissioners, developers and green job hopefuls -called or emailed Minnesota-based Windustry's wind hotline to learn more about the renewable energy. "The questions are all over the map," said David Tidball, who has been fielding calls since early 2009. "It's everything from, 'What's a wind turbine look like?' to 'How do I get involved in a wind project of my own?'" Windustry's mission is to provide accurate, unbiased and accessible information to the public about wind energy and help people across the

95

Self-assembly of InAs ring complexes on InP substrates by droplet epitaxy  

Science Conference Proceedings (OSTI)

We report the self-assembly of InAs ring complexes on InP (100) substrates by droplet epitaxy. Single-ring, ring-disk complex, and concentric double-ring structures were formed by controlling the As beam flux and substrate temperature. A clear photoluminescence signal was detected in a sample where InAs rings were embedded in InGaAs.

Noda, T.; Mano, T.; Jo, M.; Kawazu, T. [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Sakaki, H. [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya 468-8511 (Japan)

2012-09-15T23:59:59.000Z

96

Estimating large-scale fracture permeability of unsaturated rock using barometric pressure data  

E-Print Network (OSTI)

Studies Facility, Yucca Mountain, Nevada, U.S. GeologicalUnsaturated Zone, Yucca Mountain, Nevada, Water-Resourcesstudies facility, Yucca Mountain, Nevada, U.S. Geological

Wu, Yu-Shu; Zhang, Keni; Liu, Hui-Hai

2005-01-01T23:59:59.000Z

97

Calibration of Yucca Mountain unsaturated zone flow and transport model using porewater chloride data  

E-Print Network (OSTI)

of hydrogeologic units at Yucca Mountain, Nevada. U.S.infiltration for the Yucca Mountain Area, Nevada. Milestonethe unsaturated zone at Yucca Mountain, Nevada. J. Contam.

Liu, Jianchun; Sonnenthal, Eric L.; Bodvarsson, Gudmundur S.

2002-01-01T23:59:59.000Z

98

Conceptual evaluation of the potential role of fractures in unsaturated processes at Yucca Mountain  

E-Print Network (OSTI)

of Process Models, Yucca Mountain, Nevada. U.S. GeologicalUnsaturated Zone Model of Yucca Mountain, Nevada. J. Contam.Studies Facility, Yucca Mountain Project. Yucca Mountain,

Hinds, Jennifer J.; Bodvarsson, Gudmundur S.; Nieder-Westermann, Gerald H.

2002-01-01T23:59:59.000Z

99

In Situ Characterization of Unsaturated Soil Hydraulic Properties at the Maricopa Environmental Monitoring Site.  

E-Print Network (OSTI)

??Characterization of the unsaturated hydraulic properties is fundamental in modeling soil water flow and contaminant transport in the vadose zone. The objective of this study… (more)

Graham, Aaron Robert.

2004-01-01T23:59:59.000Z

100

Effects of dry fractures on matrix diffusion in unsaturated fractured rocks  

E-Print Network (OSTI)

Moridis, G. and Q. Hu, Radionuclide transport models underAn important factor in radionuclide retardation? J. Geophys.and G. Y. Bussod, Radionuclide transport in the unsaturated

Seol, Yongkoo; Liu, Hui Hai; Bodvarsson, Gudmundur S.

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Modeling studies of mountain-scale radionuclide transport in the unsaturated zone at Yucca Mountain, Nevada  

E-Print Network (OSTI)

Wu, and G.S. Bodvarsson, Radionuclide Transport Models Underdaughters of certain radionuclides. Increasing infiltrationOF MOUNTAIN-SCALE RADIONUCLIDE TRANSPORT IN THE UNSATURATED

Moridis, George J.; Seol, Yongkoo; Wu, Yu-Shu

2003-01-01T23:59:59.000Z

102

Topological interactions between ring polymers: Implications for chromatin loops  

E-Print Network (OSTI)

Chromatin looping is a major epigenetic regulatory mechanism in higher eukaryotes. Besides its role in transcriptional regulation, chromatin loops have been proposed to play a pivotal role in the segregation of entire chromosomes. The detailed topological and entropic forces between loops still remain elusive. Here, we quantitatively determine the potential of mean force between the centers of mass of two ring polymers, i.e. loops. We find that the transition from a linear to a ring polymer induces a strong increase in the entropic repulsion between these two polymers. On top, topological interactions such as the non-catenation constraint further reduce the number of accessible conformations of close-by ring polymers by about 50%, resulting in an additional effective repulsion. Furthermore, the transition from linear to ring polymers displays changes in the conformational and structural properties of the system. In fact, ring polymers adopt a markedly more ordered and aligned state than linear ones. The force...

Bohn, Manfred

2010-01-01T23:59:59.000Z

103

Unsaturated hydraulic conductivity of compacted sand-kaolin mixtures  

SciTech Connect

The unsaturated hydraulic conductivity of compacted sand-kaolin mixtures containing 0, 5, 10, and 30% kaolin (by dry weight) is measured for matric suctions, {psi}{sub m} < {approximately} 6.0 m. The measured unsaturated hydraulic conductivity (k{sub m}) values are compared with predicted unsaturated hydraulic conductivity (k{sub p}) values using the Brooks-Corey-Burdine and van Genuchten-Mualem relative hydraulic conductivity functions. In general, the accuracy of k{sub p} decreases with an increase in kaolin content or an increase in {psi}{sub m}. In addition, k{sub m} tends to be underpredicted for kaolin contents of 10 and 30% at relatively high suctions (1.0 m {le} {psi}{sub m} {le} 6.0 m) and overpredicted for kaolin contents of 0 and 5% at relatively low suctions (0.1 m {le} {psi}{sub m} < 1.0 m). For a given kaolin content and {psi}{sub m}, k{sub p} based on the Brooks-Corey-Burdine function tends to be more accurate than k{sub m} based on the van Genuchten-Mualem function. Finally, for 1.0 m {le} {psi}{sub m} {le} 6.0 m, k{sub p} based on analysis using the maximum volumetric water content ({theta}{sub m}) attained under steady-state flow conditions typically is more accurate than k{sub p} based on analysis using the saturated volumetric water content, {theta}{sub s}, where {theta}{sub m} {approximately} 84--90% of {theta}{sub s} in this study.

Chiu, T.F. [Genesis Group, Taipei (Taiwan, Province of China); Shackelford, C.D. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Civil Engineering

1998-02-01T23:59:59.000Z

104

Unsaturated Zone and Saturated Zone Transport Properties (U0100)  

Science Conference Proceedings (OSTI)

This Analysis/Model Report (AMR) summarizes transport properties for the lower unsaturated zone hydrogeologic units and the saturated zone at Yucca Mountain and provides a summary of data from the Busted Butte Unsaturated Zone Transport Test (UZTT). The purpose of this report is to summarize the sorption and transport knowledge relevant to flow and transport in the units below Yucca Mountain and to provide backup documentation for the sorption parameters decided upon for each rock type. Because of the complexity of processes such as sorption, and because of the lack of direct data for many conditions that may be relevant for Yucca Mountain, data from systems outside of Yucca Mountain are also included. The data reported in this AMR will be used in Total System Performance Assessment (TSPA) calculations and as general scientific support for various Process Model Reports (PMRs) requiring knowledge of the transport properties of different materials. This report provides, but is not limited to, sorption coefficients and other relevant thermodynamic and transport properties for the radioisotopes of concern, especially neptunium (Np), plutonium (Pu), Uranium (U), technetium (Tc), iodine (I), and selenium (Se). The unsaturated-zone (UZ) transport properties in the vitric Calico Hills (CHv) are discussed, as are colloidal transport data based on the Busted Butte UZTT, the saturated tuff, and alluvium. These values were determined through expert elicitation, direct measurements, and data analysis. The transport parameters include information on interactions of the fractures and matrix. In addition, core matrix permeability data from the Busted Butte UZTT are summarized by both percent alteration and dispersion.

J. Conca

2000-12-20T23:59:59.000Z

105

Potential wells for AMPA receptors organized in ring nanodomains  

E-Print Network (OSTI)

By combining high-density super-resolution imaging with a novel stochastic analysis, we report here a peculiar nano-structure organization revealed by the density function of individual AMPA receptors moving on the surface of cultured hippocampal dendrites. High density regions of hundreds of nanometers for the trajectories are associated with local molecular assembly generated by direct molecular interactions due to physical potential wells. We found here that for some of these regions, the potential wells are organized in ring structures. We could find up to 3 wells in a single ring. Inside a ring receptors move in a small band the width of which is of hundreds of nanometers. In addition, rings are transient structures and can be observed for tens of minutes. Potential wells located in a ring are also transient and the position of their peaks can shift with time. We conclude that these rings can trap receptors in a unique geometrical structure contributing to shape receptor trafficking, a process that sustains synaptic transmission and plasticity.

N. Hoze D. Holcman

2013-09-13T23:59:59.000Z

106

A possible redesign of the SLAC SLC damping rings  

Science Conference Proceedings (OSTI)

We describe a possible replacement for the SLC damping rings that would generate beams with normalized horizontal emittances of {gamma}{epsilon}{sub x} = 9 {times} 10{sup {minus}6} m-rad when uncoupled; this is more than three times smaller than that generated by the current rings. The primary difference between the new design and the current ring is the arc cell structure; the insertion regions, the kickers, and the RF are essentially unchanged. The new cell uses a single combined function bending magnet, roughly 70 cm in length, to replace the two bends, defocusing quadrupole, and defocusing sextupoles in the current FODO cell; the focusing quadrupole and sextupoles, used in the current cell, are also used in the new structure. The length of the new cell is identical to that of the current cell and thus nine of these new cells would simply replace the nine FODO cells in each arc of the rings.

Raubenheimer, T.O.; Early, R.; Limberg, T.; Moshammer, H.; Spencer, J.

1993-04-01T23:59:59.000Z

107

Flow dynamics and solute transport in unsaturated rock fractures  

DOE Green Energy (OSTI)

Rock fractures play an important role in flow and contaminant transport in fractured aquifers, production of oil from petroleum reservoirs, and steam generation from geothermal reservoirs. In this dissertation, phenomenological aspects of flow in unsaturated fractures were studied in visualization experiments conducted on a transparent replica of a natural, rough-walled rock fracture for inlet conditions of constant pressure and flow rate over a range of angles of inclination. The experiments demonstrated that infiltrating liquid proceeds through unsaturated rock fractures along non-uniform, localized preferential flow paths. Even in the presence of constant boundary conditions, intermittent flow was a persistent flow feature observed, where portions of the flow channel underwent cycles of snapping and reforming. Two modes of intermittent flow were observed, the pulsating blob mode and the rivulet snapping mode. A conceptual model for the rivulet snapping mode was proposed and examined using idealized, variable-aperture fractures. The frequency of intermittent flow events was measured in several experiments and related to the capillary and Bond numbers to characterize this flow behavior.

Su, G. W.

1999-10-01T23:59:59.000Z

108

Reversible Seeding in Storage Rings  

Science Conference Proceedings (OSTI)

We propose to generate steady-state microbunching in a storage ring with a reversible seeding scheme. High gain harmonic generation (HGHG) and echo-enabled harmonic generation (EEHG) are two promising methods for microbunching linac electron beams. Because both schemes increase the energy spread of the seeded beam, they cannot drive a coherent radiator turn-by-turn in a storage ring. However, reversing the seeding process following the radiator minimizes the impact on the electron beam and may allow coherent radiation at or near the storage ring repetition rate. In this paper we describe the general idea and outline a proof-of-principle experiment. Electron storage rings can drive high average power light sources, and free-electron lasers (FELs) are now producing coherent light sources of unprecedented peak brightness While there is active research towards high repetition rate FELs (for example, using energy recovery linacs), at present there are still no convenient accelerator-based sources of high repetition rate, coherent radiation. As an alternative avenue, we recently proposed to establish steady-state microbunching (SSMB) in a storage ring. By maintaining steady-state coherent microbunching at one point in the storage ring, the beam generates coherent radiation at or close to the repetition rate of the storage ring. In this paper, we propose a method of generating a microbunched beam in a storage ring by using reversible versions of linac seeding schemes.

Ratner, Daniel; Chao, Alex; /SLAC

2011-12-14T23:59:59.000Z

109

Node-Capacitated Ring Routing  

Science Conference Proceedings (OSTI)

We consider the node-capacitated routing problem in an undirected ring network along with its fractional relaxation, the node-capacitated multicommodity flow problem. For the feasibility problem, Farkas' lemma provides a characterization for general ... Keywords: half-integral flow, multicommodity flow, ring routing

AndrÁs Frank; Bruce Shepherd; Vivek Tandon; Zoltán Végh

2002-05-01T23:59:59.000Z

110

Vapor Flow to Horizontal Wells in Unsaturated Zones Hongbin Zhan* and Eungyu Park  

E-Print Network (OSTI)

Vapor Flow to Horizontal Wells in Unsaturated Zones Hongbin Zhan* and Eungyu Park ABSTRACT and vaporthree dimensional form for a horizontal-well sink in an unsaturated zone. This is done by solving; horizontal-well axis to obtain the solution of flow to a horizontal-well Zhan and Cao, 2000). Horizontal

Zhan, Hongbin

111

Solute spreading in nonstationary flows in bounded, heterogeneous unsaturated-saturated media  

E-Print Network (OSTI)

three cases: transport in a mean gravity-dominated flow, in an unsaturated flow with a water table in nonstationary flows in bounded, heterogeneous unsaturated-saturated media, Water Resour. Res., 39(3), 1049, doi et al., 1991; Jury and Scotter, 1994; Harter and Yeh, 1996a, 1996b]. [3] In most of these models

Lu, Zhiming

112

A Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca  

Open Energy Info (EERE)

Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca Mountain, Nevada Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca Mountain, Nevada Details Activities (0) Areas (0) Regions (0) Abstract: A three-dimensional unsaturated-zone numerical model has been developed to simulate flow and distribution of moisture, gas and heat at Yucca Mountain, Nevada, a potential repository site for high-level radioactive waste. The model takes into account the simultaneous flow dynamics of liquid water, vapor, air and heat in the highly heterogeneous, fractured porous rock in the unsaturated zone (UZ). This model is intended for use in the prediction of the current and future conditions in the UZ so

113

Wedding ring shaped excitation coil  

DOE Patents (OSTI)

A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management. The lamp head is preferably an integrated lamp head comprising a metal matrix composite surrounding an insulating ceramic with the excitation integrally formed on the ceramic. A novel solid-state oscillator preferably provides RF power to the lamp. The oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency.

MacLennan, Donald A. (Gaithersburg, MD); Tsai, Peter (Olney, MD)

2001-01-01T23:59:59.000Z

114

Ion Rings for Magnetic Fusion  

Science Conference Proceedings (OSTI)

This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation of a reactor-scale FRC, and the FIREX program was intended to test the ideas behind this approach. We will describe in this report the technological development path and advances in physics understanding that allowed FIREX to reach a regime in which ion rings were reproducibly created with up to about half the current necessary to produce field reversal. Unfortunately, the experiments were limited to this level by a fundamental, unanticipated aspect of the physics of strong ion rings in plasma. The FIREX ring is a strongly anisotropic, current-carrying population of ions moving faster than the Alfven speed in the background plasma. The rapidly changing ring current excites very large-amplitude Alfven waves in the plasma, and these waves strongly affect the ring, causing rapid energy loss in a way that is not compatible with the success of the ring trapping scenario around which FIREX was designed. The result was that FIREX rings were always very short-lived. We will discuss the implication of these results for possible future use of large-orbit ions in FRCs. In short, it appears that a certain range of the parameters characterizing the ring Alfven mach number and distribution function must be avoided to allow the existence of a long-lived energetic ion component in an FRC. This report will explain why FIREX experimental results cannot be directly scaled to quantitatively predict this range for a particular FRC configuration. This will require accurate, three-dimensional simulations. FIREX results do constitute a very good dataset for validating such a code, and simulations already carried out during this program provide a guide to the important physics involved.

Greenly, John, B.

2005-07-31T23:59:59.000Z

115

Elements present in leach solutions from unsaturated spent fuel tests  

SciTech Connect

Preliminary results for the composition of the leachate from unsaturated tests at 90{degrees}C with spent fuel for 55--134 days with J-13 groundwater are reported. The pH of the leachate solutions was found to be acidic, ranging from 4 to 7. The actinide concentrations were 10{sup 5} greater than those reported for saturated spent fuel tests in which the leachate pH was 8. We also found that most species in the leachate were present as colloids containing both americium and curium. The presence of actinides in a form not currently included in repository radionuclide transport models provides information that can be used in spent fuel reaction modeling, the performance assessment of the repository and the design of the engineering barrier system. This report was prepared as part of the Yucca Mountain Site Characterization Project

Finn, P.A.; Bates, J.K.; Hoh, J.C.; Emery, J.W.; Hafenrichter, L.D.; Buck, E.C.; Gong, M.

1993-10-01T23:59:59.000Z

116

Univariate Ore Polynomial Rings in Computer Algebra  

E-Print Network (OSTI)

describe a computer algebra library for basic operations in an arbitrary Ore ring. ... worth mentioning that the idea of using Ore rings in computer algebra was first  ...

117

Pistons and Piston Ring Assembly  

Science Conference Proceedings (OSTI)

Table 3   Typical piston ring materials...0.3 max 0.1â??0.5 â?¦ 540 78 155 22 200â??400 BS2789 SNG Sand or centrifugally cast Varies according to mechanical

118

Why Are There Agulhas Rings?  

Science Conference Proceedings (OSTI)

The recently proposed analytical theory of Nof and Pichevin describing the intimate relationship between retroflecting currents and the production of rings is examined numerically and applied to the Agulhas Current. Using a reduced-gravity 1½-...

Thierry Pichevin; Doron Nof; Johann Lutjeharms

1999-04-01T23:59:59.000Z

119

Electrically charged dilatonic black rings  

E-Print Network (OSTI)

In this note we present (electrically) charged dilatonic black ring solutions of the Einstein-Maxwell-dilaton theory in five dimensions and we consider their physical properties. These solutions are static and as in the neutral case possess a conical singularity. We show how one may remove the conical singularity by application of a Harrison transformation, which physically corresponds to supporting the charged ring with an electric field. Finally, we discuss the slowly rotating case for arbitrary dilaton coupling.

Hari K. Kunduri; James Lucietti

2004-12-14T23:59:59.000Z

120

Black Saturn with dipole ring  

E-Print Network (OSTI)

We present a new stationary, asymptotically flat solution of 5D Einstein-Maxwell gravity describing a Saturn-like black object: a rotating black hole surrounded by a rotating dipole black ring. The solution is generated by combining the vacuum black Saturn solution and the vacuum black ring solution with appropriately chosen parameters. Some basic properties of the solution are analyzed and the basic quantities are calculated.

Stoytcho Yazadjiev

2007-05-13T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Ring resonant cavities for spectroscopy  

DOE Patents (OSTI)

Ring-shaped resonant cavities for spectroscopy allow a reduction in optical feedback to the light source, and provide information on the interaction of both s- and p-polarized light with samples. A laser light source is locked to a single cavity mode. An intracavity acousto-optic modulator may be used to couple light into the cavity. The cavity geometry is particularly useful for Cavity Ring-Down Spectroscopy (CRDS). 6 figs.

Zare, R.N.; Martin, J.; Paldus, B.A.; Xie, J.

1999-06-15T23:59:59.000Z

122

The Sinking of Warm-Core Rings  

Science Conference Proceedings (OSTI)

Intense cooling of a warm-core ring or warming of the fluids surrounding a ring can increase the density of that ring relative to the surrounding fluids. This increase in density can cause the ring to sink under the surrounding fluids. A simple ...

Rick Chapman; Doron Nof

1988-04-01T23:59:59.000Z

123

On Algebraic Multi-Ring Spaces  

E-Print Network (OSTI)

A Smarandache multi-space is a union of $n$ spaces $A_1,A_2,..., A_n$ with some additional conditions holding. Combining Smarandache multi-spaces with rings in classical ring theory, the conception of multi-ring spaces is introduced. Some characteristics of a multi-ring space are obtained in this paper.

Linfan Mao

2005-10-22T23:59:59.000Z

124

Plasma deposited rider rings for hot displacer  

DOE Patents (OSTI)

A hot cylinder for a cryogenic refrigerator having two plasma spray deposited rider rings of a corrosion and abrasion resistant material provided in the rider ring grooves, wherein the rider rings are machined to the desired diameter and width after deposition. The rider rings have gas flow flats machined on their outer surface.

Kroebig, Helmut L. (Rolling Hills, CA)

1976-01-01T23:59:59.000Z

125

Double acting stirling engine piston ring  

DOE Patents (OSTI)

A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

Howarth, Roy B. (Clifton Park, NY)

1986-01-01T23:59:59.000Z

126

Double acting stirling engine piston ring  

Science Conference Proceedings (OSTI)

A piston ring design for a Stirling engine wherein the contact pressure between the piston and the cylinder is maintained at a uniform level, independent of engine conditions through a balancing of the pressure exerted upon the ring's surface and thereby allowing the contact pressure on the ring to be predetermined through the use of a preloaded expander ring.

Howarth, Roy B. (Clifton Park, NY)

1986-01-01T23:59:59.000Z

127

Concentric ring flywheel without expansion separators  

DOE Patents (OSTI)

A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion.

Kuklo, Thomas C. (Oakdale, CA)

1999-01-01T23:59:59.000Z

128

Concentric ring flywheel without expansion separators  

DOE Patents (OSTI)

A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion. 3 figs.

Kuklo, T.C.

1999-08-24T23:59:59.000Z

129

Modeling Unsaturated Flow and Transport Processes in Fractured Tuffs of Yucca Mountain  

E-Print Network (OSTI)

zone site-scale model, Yucca Mountain Site Characterizationsite-scale model, Yucca Mountain Project Milestone 3GLM105M,unsaturated zone, Yucca Mountain, Nevada. Water-Resources

Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Bodvarsson, G.S.

2003-01-01T23:59:59.000Z

130

Analysis of pumping-induced unsaturated regions beneath a perennial river  

E-Print Network (OSTI)

the period over which water can be produced at a particulardesaturated and water could no longer be produced at a rateis unsaturated, but water can still be produced at a rate of

Su, G.W.; Jasperse, J.; Seymour, D.; Constantz, J.; Zhou, Q.

2008-01-01T23:59:59.000Z

131

Analyzing flow patterns in unsaturated fractured rock of YuccaMountain using an integrated modeling approach  

SciTech Connect

This paper presents a series of modeling investigations to characterize percolation patterns in the unsaturated zone of Yucca Mountain, Nevada, a proposed underground repository site for storing high-level radioactive waste. The investigations are conducted using a modeling approach that integrates a wide variety of moisture, pneumatic, thermal, and isotopic geochemical field data into a comprehensive three-dimensional numerical model through model calibration. This integrated modeling approach, based on a dual-continuum formulation, takes into account the coupled processes of fluid and heat flow and chemical isotopic transport in Yucca Mountain's highly heterogeneous, unsaturated fractured tuffs. In particular, the model results are examined against different types of field-measured data and used to evaluate different hydrogeological conceptual models and their effects on flow patterns in the unsaturated zone. The objective of this work to provide understanding of percolation patterns and flow behavior through the unsaturated zone, which is a crucial issue in assessing repository performance.

Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Pan, Lehua; Bodvarsson,Gudmundur S.

2003-11-03T23:59:59.000Z

132

Split ring containment attachment device  

DOE Patents (OSTI)

A containment attachment device is described for operatively connecting a glovebag to plastic sheeting covering hazardous material. The device includes an inner split ring member connected on one end to a middle ring member wherein the free end of the split ring member is inserted through a slit in the plastic sheeting to captively engage a generally circular portion of the plastic sheeting. A collar portion having an outer ring portion is provided with fastening means for securing the device together wherein the glovebag is operatively connected to the collar portion. Hazardous material such as radioactive waste may be sealed in plastic bags for small items or wrapped in plastic sheeting for large items. Occasionally the need arises to access the hazardous material in a controlled manner, that is, while maintaining total containment. Small items could be placed entirely inside a containment glovebag. However, it may not be possible or practical to place large items inside a containment; instead, one or more glovebags could be attached to the plastic sheeting covering the hazardous material. It is this latter application for which the split ring containment attachment device is intended.

Sammel, A.G.

1995-12-31T23:59:59.000Z

133

Topological interactions between ring polymers: Implications for chromatin loops  

E-Print Network (OSTI)

Chromatin looping is a major epigenetic regulatory mechanism in higher eukaryotes. Besides its role in transcriptional regulation, chromatin loops have been proposed to play a pivotal role in the segregation of entire chromosomes. The detailed topological and entropic forces between loops still remain elusive. Here, we quantitatively determine the potential of mean force between the centers of mass of two ring polymers, i.e. loops. We find that the transition from a linear to a ring polymer induces a strong increase in the entropic repulsion between these two polymers. On top, topological interactions such as the non-catenation constraint further reduce the number of accessible conformations of close-by ring polymers by about 50%, resulting in an additional effective repulsion. Furthermore, the transition from linear to ring polymers displays changes in the conformational and structural properties of the system. In fact, ring polymers adopt a markedly more ordered and aligned state than linear ones. The forces and accompanying changes in shape and alignment between ring polymers suggest an important regulatory function of such a topology in biopolymers. We conjecture that dynamic loop formation in chromatin might act as a versatile control mechanism regulating and maintaining different local states of compaction and order.

Manfred Bohn; Dieter W. Heermann

2010-01-24T23:59:59.000Z

134

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Å-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

135

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Å-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

136

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Å-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

137

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported by motor proteins. These tiny machines convert the energy gained from hydrolysing ATP into a series of small conformational changes that allow them to literally "walk" along microscopic tracks. Motor proteins (in the kinesin and myosin families) have been extensively studied by x-ray crystallography, but until recently there was little molecular structural information for dyneins, another type of motor protein. A group from the University of California, San Francisco, working at ALS Beamline 8.3.1 has reported the 6-Å-resolution structure of the motor domain of dynein in yeast. It reveals details of the ring-shaped motor as well as a new, unanticipated feature called the buttress that may play an important role in dynein's mechanical cycle.

138

Modeling flow and transport in unsaturated fractured rock: An evaluation of the continuum approach  

Science Conference Proceedings (OSTI)

Because the continuum approach is relatively simple and straightforward to implement, it has been commonly used in modeling flow and transport in unsaturated fractured rock. However, the usefulness of this approach can be questioned in terms of its adequacy for representing fingering flow and transport in unsaturated fractured rock. The continuum approach thus needs to be evaluated carefully by comparing simulation results with field observations directly related to unsaturated flow and transport processes. This paper reports on such an evaluation, based on a combination of model calibration and prediction, using data from an infiltration test carried out in a densely fractured rock within the unsaturated zone of Yucca Mountain, Nevada. Comparisons between experimental and modeling results show that the continuum approach may be able to capture important features of flow and transport processes observed from the test. The modeling results also show that matrix diffusion may have a significant effect on the overall transport behavior in unsaturated fractured rocks, which can be used to estimate effective fracture-matrix interface areas based on tracer transport data. While more theoretical, numerical, and experimental studies are needed to provide a conclusive evaluation, this study suggests that the continuum approach is useful for modeling flow and transport in unsaturated, densely fractured rock.

Liu, Hui-Hai; Haukwa, Charles B.; Ahlers, C. Fredrik; Bodvarsson, Gudmundur S.; Flint, Alan L.; Guertal, William B.

2002-09-01T23:59:59.000Z

139

NSLS Booster & Linac Ring  

NLE Websites -- All DOE Office Websites (Extended Search)

Booster & Linac Ring Booster & Linac Ring Booster Operating Parameters (pdf) Lattice Information (pdf) Mechanical Drawing (pdf) Standard Operating Mode Electrons are injected into the NSLS storage rings from a 750 MeV booster synchrotron fed by a 120 MeV linac. The electrons are first produced in a 100 KeV triode electron gun. The gun is pulsed at the booster revolution period, 94.6 nsec, seven times per booster cycle. Each pulse is 5 nsec long and supplies about 17 microbunches in the linac. After acceleration in the linac, the beam is injected into the booster on seven successive turns. Multi-turn injection in the booster is accomplished in the following way: The beam is deflected into the booster by a septum magnet. The first linac pulse goes around the booster and returns to the injection point just as

140

Electrokinetic removal of uranium from contaminated, unsaturated soils  

SciTech Connect

Electrokinetic remediation of uranium-contaminated soil was studied in a series of laboratory-scale experiments in test cells with identical geometry using quartz sand at approximately 10 percent moisture content. Uranium, when present in the soil system as an anionic complex, could be migrated through unsaturated soil using electrokinetics. The distance that the uranium migrated in the test cell was dependent upon the initial molar ratio of citrate to uranium used. Over 50 percent of the uranium was recovered from the test cells using the citrate and carbonate complexing agents over of period of 15 days. Soil analyses showed that the uranium remaining in the test cells had been mobilized and ultimately would have been extracted. Uranium extraction exceeded 90 percent in an experiment that was operated for 37 days. Over 70 percent of the uranium was removed from a Hanford waste sample over a 55 day operating period. Citrate and carbonate ligand utilization ratios required for removing 50 percent of the uranium from the uranium-contaminated sand systems were approximately 230 moles ligand per mole uranium and 1320 moles ligand per mole uranium for the waste. Modifying the operating conditions to increasing the residence time of the complexants is expected to improved the utilization efficiency of the complexing agent.

Booher, W.F. [IT Corp., Albuquerque, NM (United States); Lindgren, E.R.; Brady, P.V. [Sandia National Laboratories, Albuquerque, NM (United States)

1997-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

The effect of fuel type in unsaturated spent fuel tests  

Science Conference Proceedings (OSTI)

Two well-characterized types of spent nuclear fuel (ATM-103 and ATM-106) were tested under simulated unsaturated conditions with simulated groundwater at 90{degree}C. The actinides present in the leachate were measured after periods of approximately 60, 120, and 275 days. The vessels were acid stripped after 120 and 275 days. Both colloidal and soluble actinide species were detected in the leachates which had pHs ranging from 4 to 7. Alpha spectroscopy studies of filtered and unfiltered leachates showed that large amounts of actinides may be bound in colloids. The uranium phases identified in the colloids were schoepite and soddyite. The actinide release behavior of the two fuels appears to be different. The ATM-106 fuel began to release actinides later than the ATM-103 fuel, but after 275 days, it had released more. The amount of americium released from the two fuels was a higher percentage of the maximum amount of americium present than was the percentage of the simultaneous amount of uranium released.

Finn, P.A.; Gong, M.; Bates, J.K.; Emery, J.W.; Hoh, J.C.

1994-04-01T23:59:59.000Z

142

Simulation of heat transfer in the unsaturated zone  

SciTech Connect

Heat transfer can play an important role in fluid flow near the emplacement site of high-level nuclear waste. The effects on far- field flow can be important in understanding net moisture fluxes above the repository zone. The convection in the unsaturated zone at the Yucca Mountain site was responsible for this movement. If this is so, then the convection could provide a mechanism for drying the rock above the repository zone and thus provide a buffer for heavy rainfall events. In addition, the convection would increase the movement of gaseous radionuclides such as {sup 14}CO{sub 2}, tritiated water vapor, and {sup 129}I (Weeks, 1987). Because of the complexity of the problem, numerical models were required to calculate gas flow and vapor transport at the site. Kipp previously modeled this problem using the code HST3D. This code represents the flow of a single-phase fluid with both heat- and mass-transfer effects included. Water density and partial pressure effects are accounted for by the virtual temperature method. In this paper, the problem was simulated using the code FEHMN, a finite-element heat- and mass-transfer code being developed for the Yucca Mountain Project. The work described in this paper was done in preparation of the upcoming problem to be formulated for the Performance Assessment Calculation Exercise. 5 refs., 9 figs., 1 tab.

Zyvoloski, G.

1990-02-01T23:59:59.000Z

143

Soil characterization methods for unsaturated low-level waste sites  

SciTech Connect

To support a license application for the disposal of low-level radioactive waste (LLW), applicants must characterize the unsaturated zone and demonstrate that waste will not migrate from the facility boundary. This document provides a strategy for developing this characterization plan. It describes principles of contaminant flow and transport, site characterization and monitoring strategies, and data management. It also discusses methods and practices that are currently used to monitor properties and conditions in the soil profile, how these properties influence water and waste migration, and why they are important to the license application. The methods part of the document is divided into sections on laboratory and field-based properties, then further subdivided into the description of methods for determining 18 physical, flow, and transport properties. Because of the availability of detailed procedures in many texts and journal articles, the reader is often directed for details to the available literature. References are made to experiments performed at the Las Cruces Trench site, New Mexico, that support LLW site characterization activities. A major contribution from the Las Cruces study is the experience gained in handling data sets for site characterization and the subsequent use of these data sets in modeling studies.

Wierenga, P.J.; Young, M.H. (Arizona Univ., Tucson, AZ (United States). Dept. of Soil and Water Science); Gee, G.W.; Kincaid, C.T. (Pacific Northwest Lab., Richland, WA (United States)); Hills, R.G. (New Mexico State Univ., Las Cruces, NM (United States). Dept. of Mechanical Engineering); Nicholson, T.J.; Cady, R.E. (Nuclear Regulatory Commission, Washington, DC (United States))

1993-01-01T23:59:59.000Z

144

Moisture content and unsaturated conditions in UMTRA project radon barriers  

SciTech Connect

A typical Uranium Mill Tailings Remedial Action (UMTRA) Project disposal facility consists of uranium tailings and other contaminated materials covered by a three to six foot thick radon barrier and six inches of filter sand, overlain by one foot of erosion-protection riprap. To comply with the proposed US Environmental Protection Agency groundwater protection standards applicable to the UMTRA Project, groundwater concentration limits of hazardous constitutents cannot be exceeded at the point of compliance, which is the downgradient limit of the waste management area. The typical radon barrier has a saturated hydraulic conductivity of approximately 1 {times} 10{sup {minus}7} centimeters per second (cm/s). Long-term seepage rates from a disposal facility with an unsaturated radon barrier may permit the concentration limits to be met at the point of compliance. Field studies were undertaken to measure the percent saturation and the relation of percent saturation to soil tension, and to predict the hydraulic conductivity as a function of percent saturation in radon barriers at three UMTRA Project disposal facilities that have been completed for up to two years. Presently typical covers have been completed at the Shiprock, Clive, and Burrell sites, and they are planned or under construction at the Ambrosia Lake, Green River, Lakeview, Mexican Hat, Slick Rock, and Tuba City sites. 2 refs., 13 figs., 1 tab.

Not Available

1988-12-01T23:59:59.000Z

145

Power Supplies for Precooler Ring  

SciTech Connect

Eight power supplies will energize the antiproton Precooler ring. there will be two series connected supplies per quadrant. These supplies will power 32 dipole and 19 quadrupole magnets. The resistance and inductance per quadrant is R = 1.4045 Ohms and L = 0.466. Each powr supply will have 12-phase series bridge rectifiers and will be energized from the 480 V 3-phase grid. The total of eight power supplies are numbered IA, IIA, IIIA, IVA, and IB, IIB, IIIB, and IVB. Each quadrant will contain one A and one B supply. A block diagram of the Precooler ring with its power supplies is shown in Figure 1.

Fuja, Raymond; Praeg, Walter

1980-12-12T23:59:59.000Z

146

Oceanic Rings and Jets as Statistical Equilibrium States  

Science Conference Proceedings (OSTI)

Equilibrium statistical mechanics of two-dimensional flows provides an explanation and a prediction for the self-organization of large-scale coherent structures. This theory is applied in this paper to the description of oceanic rings and jets, in ...

Antoine Venaille; Freddy Bouchet

2011-10-01T23:59:59.000Z

147

Conical O-ring seal  

DOE Patents (OSTI)

A shipping container for radioactive or other hazardous materials which has a conical-shaped closure containing grooves in the conical surface thereof and an O-ring seal incorporated in each of such grooves. The closure and seal provide a much stronger, tighter and compact containment than with a conventional flanged joint.

Chalfant, Jr., Gordon G. (North Augusta, SC)

1984-01-01T23:59:59.000Z

148

DEVELOPMENT AND APPLICATIONS OF THE UAL BASED SNS RING SIMULATION ENVIRONMENT.  

SciTech Connect

The SNS Ring off-line parallel simulation environment based on the Unified Accelerator Libraries (UAL) has en implemented and used for extensive full-scale beam dynamics studies arising in high-intensity ring. The paper describes the structure of this environment and its application to various high-intensity topics and diagnostics modeling.

MALITSKY,N.; CAMERON,P.; FEDOTOV,A.V.; SMITH,J.; WEI,J.

2002-04-08T23:59:59.000Z

149

Universal polynomials in lambda rings and the K-theory of the infinite loop space tmf  

E-Print Network (OSTI)

The algebraic structure of the K-theory of a topological space is described by the more general notion of a lambda ring. We show how computations in a lambda ring are facilitated by the use of Adams operations, which are ...

Hopkinson, John R. (John Robert)

2006-01-01T23:59:59.000Z

150

Rings with the Beachy-Blair condition  

E-Print Network (OSTI)

A ring satisfies the left Beachy-Blair condition if each of its faithful left ideal is cofaithful. Every left zip ring satisfies the left Beachy-Blair condition, but both properties are not equivalent. In this paper we will study the similarities and the differences between zip rings and rings with the Beachy-Blair condition. We will also study the relationship between the Beachy-Blair condition of a ring and its skew polynomial and skew power series extensions. We give an example of a right zip ring that is not left zip, proving that the zip property is not symmetric.

Rodríguez-Jorge, Elena

2010-01-01T23:59:59.000Z

151

Cavity-locked ring down spectroscopy  

DOE Patents (OSTI)

Distinct locking and sampling light beams are used in a cavity ring-down spectroscopy (CRDS) system to perform multiple ring-down measurements while the laser and ring-down cavity are continuously locked. The sampling and locking light beams have different frequencies, to ensure that the sampling and locking light are decoupled within the cavity. Preferably, the ring-down cavity is ring-shaped, the sampling light is s-polarized, and the locking light is p-polarized. Transmitted sampling light is used for ring-down measurements, while reflected locking light is used for locking in a Pound-Drever scheme.

Zare, Richard N. (Stanford, CA); Paldus, Barbara A. (Stanford, CA); Harb, Charles C. (Palo Alto, CA); Spence, Thomas (Union City, CA)

2000-01-01T23:59:59.000Z

152

Wear reduction systems liquid piston ring  

DOE Green Energy (OSTI)

The overall objective of the program was to demonstrate the technical feasibility of achieving an acceptable wear rate for the cylinder liner, piston, and piston rings in a coal/water-slurry-fueled engine that utilized the concept of a liquid piston ring above the conventional piston rings and to identify technical barriers and required research and development. The study included analytical modeling of the system, a bench study of the fluid motion in the liquid piston ring, and a single-cylinder test rig for wear comparison. A system analysis made on the different variations of the liquid supply system showed the desirability of the once-through version from the standpoint of system simplicity. The dynamics of the liquid ring were modeled to determine the important design parameters that influence the pressure fluctuation in the liquid ring during a complete engine cycle and the integrity of the liquid ring. This analysis indicated the importance of controlling heat transfer to the liquid ring through piston and liner to avoid boiling the liquid. A conceptual piston design for minimizing heat transfer is presented in this report. Results showed that the liquid piston ring effectively reduced the solid particles on the wall by scrubbing, especially in the case where a surfactant was added to the water. The wear rates were reduced by a factor of 2 with the liquid ring. However, leakage of the contaminated liquid ring material past the top ring limited the effectiveness of the liquid ring concept. 8 refs., 33 figs., 1 tab.

Raymond, R.J.; Chen, T.N.; DiNanno, L.

1990-09-01T23:59:59.000Z

153

Characterization of Spatial Variability of Hydrogeologic Properties for Unsaturated Flow in the Fractured Rocks at Yucca Mountain, Nevada  

E-Print Network (OSTI)

using matrix properties , Yucca Mountain, Nevada, USGS Waterof hydrogeologic units at Yucca Mountain, Nevada, U.S.Unsaturated Zone, Yucca Mountain, Nevada . Water-Resources

Zhou, Quanlin; Bodvarsson, Gudmundur S.; Liu, Hui-Hai; Oldenburg, Curtis M.

2002-01-01T23:59:59.000Z

154

Sensitivity Analysis Of Hydrological Parameters In Modeling Flow And Transport In The Unsaturated Zone Of Yucca Mountain  

E-Print Network (OSTI)

Unsaturated Zone of Yucca Mountain Keni Zhang, Yu-Shu Wu,volcanic deposits at Yucca Mountain have been intensivelyhydraulic properties, Yucca Mountain Introduction Site

Zhang, Keni; Wu, Yu-Shu; Houseworth, James E

2006-01-01T23:59:59.000Z

155

Tracer Leakage from Modeled Agulhas Rings  

Science Conference Proceedings (OSTI)

In a numerical, isopycnal, ocean model the mixing is investigated with the environment of two idealized Agulhas rings, one that splits, and one that remains coherent. The evolution of a passive tracer, initially contained within the rings, shows ...

L. de Steur; P. J. van Leeuwen; S. S. Drijfhout

2004-06-01T23:59:59.000Z

156

STORAGE RING LS-41 E. A. Crosbie  

NLE Websites -- All DOE Office Websites (Extended Search)

(112785) STORAGE RING LS-41 E. A. Crosbie November 27, 1985 MIXED WIGGLER, UNDULATOR LATTICE PARAMETERS STOR-RING (E. A. Crosbie) 112585 Mixed Wiggler, Undu1ator Lattice...

157

Mechanical seal having a single-piece, perforated mating ring  

DOE Patents (OSTI)

A mechanical seal (e.g., single mechanical seals, double mechanical seals, tandem mechanical seals, bellows, pusher mechanical seals, and all types of rotating and reciprocating machines) with reduced contact surface temperature, reduced contact surface wear, or increased life span. The mechanical seal comprises a rotating ring and a single-piece, perforated mating ring, which improves heat transfer by controllably channeling coolant flow through the single-piece mating ring such that the coolant is in substantially uniform thermal contact with a substantial portion of the interior surface area of the seal face, while maintaining the structural integrity of the mechanical seal and minimizing the potential for coolant flow interruptions to the seal face caused by debris or contaminants (e.g., small solids and trash) in the coolant.

Khonsari, Michael M. (Baton Rouge, LA); Somanchi, Anoop K. (Fremont, CA)

2007-08-07T23:59:59.000Z

158

Used Fuel Disposition Campaign Phase I Ring Compression Testing...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Phase I Ring Compression Testing of High Burnup Cladding Used Fuel Disposition Campaign Phase I Ring Compression Testing of High Burnup Cladding The purpose of ring compression...

159

Polynomial Fusion Rings of Logarithmic Minimal Models  

E-Print Network (OSTI)

We identify quotient polynomial rings isomorphic to the recently found fundamental fusion algebras of logarithmic minimal models.

Jorgen Rasmussen; Paul A. Pearce

2007-09-21T23:59:59.000Z

160

Transverse instability in high intensity proton rings  

SciTech Connect

In recent years, many applications are being considered for low energy high intensity proton synchrotrons. Most high intensity proton rings are at low energy below transition. Several aspects of the beam dynamics of this kind of rings are different from the electron or high energy rings. The transverse microwave instabilities will be discussed in this article.

Zhang, S.Y.; Weng, W.T.

1997-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

APS storage ring vacuum system  

SciTech Connect

The Advanced Photon Source synchrotron radiation facility, under construction at the Argonne National Laboratory, incorporates a large ring for the storage of 7 GeV positrons for the generation of photon beams for the facility's experimental program. The Storage Ring's 1104 m circumference is divided into 40 functional sectors. The sectors include vacuum, beam transport, control, acceleration and insertion device components. The vacuum system, which is designed to operate at a pressure of 1 n Torr, consists of 240 connected sections, the majority of which are fabricated from an aluminum alloy extrusion. The sections are equipped with distributed NeG pumping, photon absorbers with lumped pumping, beam position monitors, vacuum diagnostics and valving. The details of the vacuum system design, selected results of the development program and general construction plans are presented. 11 refs., 6 figs., 3 tabs.

Niemann, R.C.; Benaroya, R.; Choi, M.; Dortwegt, R.J.; Goeppner, G.A.; Gonczy, J.; Krieger, C.; Howell, J.; Nielsen, R.W.; Roop, B.; Wehrle, R.B.

1990-01-01T23:59:59.000Z

162

Recent developments in the techniques of controlling and measuring suction in unsaturated soils  

E-Print Network (OSTI)

The difficulty of measuring and controlling suction in unsaturated soils is one of the reasons why the development of the mechanics of unsaturated soils has not been as advanced as that of saturated soils. However, significant developments have been carried out in the last decade in this regard. In this paper, a re-view of some developments carried out in the techniques of controlling suction by using the axis translation, the osmotic method and the vapour control technique is presented. The paper also deals with some recent de-velopments in the direct measurement of suction by using high capacity tensiometers and in the measurement of high suction by using high range psychrometers. The recent progresses made in these techniques have been significant and will certainly help further experimental investigation of the hydromechanical behaviour of un-saturated soils.

Delage, Pierre; Tarantino, Alessandro

2008-01-01T23:59:59.000Z

163

Saturated-Unsaturated flow in a Compressible Leaky-unconfined Aquifer  

E-Print Network (OSTI)

An analytical solution is developed for three-dimensional flow towards a partially penetrating large-diameter well in an unconfined aquifer bounded below by an aquitard of finite or semi-infinite extent. The analytical solution is derived using Laplace and Hankel transforms, then inverted numerically. Existing solutions for flow in leaky unconfined aquifers neglect the unsaturated zone following an assumption of instantaneous drainage assumption due to Neuman [1972]. We extend the theory of leakage in unconfined aquifers by (1) including water flow and storage in the unsaturated zone above the water table, and (2) allowing the finite-diameter pumping well to partially penetrate the aquifer. The investigation of model-predicted results shows that leakage from an underlying aquitard leads to significant departure from the unconfined solution without leakage. The investigation of dimensionless time-drawdown relationships shows that the aquitard drawdown also depends on unsaturated zone properties and the pumping-well wellbore storage effects.

Phoolendra K. Mishra; Velimir V. Vessilinov; Kristopher L. Kuhlman

2011-11-04T23:59:59.000Z

164

Saturated-Unsaturated flow in a Compressible Leaky-unconfined Aquifer  

E-Print Network (OSTI)

An analytical solution is developed for three-dimensional flow towards a partially penetrating large-diameter well in an unconfined aquifer bounded below by an aquitard of finite or semi-infinite extent. The analytical solution is derived using Laplace and Hankel transforms, then inverted numerically. Existing solutions for flow in leaky unconfined aquifers neglect the unsaturated zone following an assumption of instantaneous drainage assumption due to Neuman [1972]. We extend the theory of leakage in unconfined aquifers by (1) including water flow and storage in the unsaturated zone above the water table, and (2) allowing the finite-diameter pumping well to partially penetrate the aquifer. The investigation of model-predicted results shows that leakage from an underlying aquitard leads to significant departure from the unconfined solution without leakage. The investigation of dimensionless time-drawdown relationships shows that the aquitard drawdown also depends on unsaturated zone properties and the pumping...

Mishra, Phoolendra K; Kuhlman, Kristopher L

2011-01-01T23:59:59.000Z

165

Synchronization in semiconductor laser rings  

E-Print Network (OSTI)

We examine the dynamics of semiconductor lasers coupled in a ring configuration. The lasers, which have stable output intensity when isolated, behave chaotically when coupled unidirectionally in a closed chain. In this way, we show that neither feedback nor bidirectional coupling is necessary to induce chaotic dynamics at the laser output. We study the synchronization phenomena arising in this particular coupling architecture, and discuss its possible application to chaos-based communications. Next, we extend the study to bidirectional coupling and propose an appropriate technique to optical chaos encryption/decryption in closed chains of mutually coupled semiconductor lasers.

Javier M. Buldu; M. C. Torrent; Jordi Garcia-Ojalvo

2006-10-06T23:59:59.000Z

166

Reactive transport model for the ambient unsaturated hydrogeochemical system at Yucca mountain, Nevada  

Science Conference Proceedings (OSTI)

To assist a technical review of a potential application for a geologic repository, a reactive transport model is presented for the ambient hydrogeochemical system at Yucca Mountain (YM). The model simulates two-phase, nonisothermal, advective and diffusive ... Keywords: Yucca mountain, geochemistry, groundwater chemistry, groundwater flow and transport, hydrology, reactive transport model, unsaturated zone

Lauren Browning; William M. Murphy; Chandrika Manepally; Randall Fedors

2003-04-01T23:59:59.000Z

167

Lithium Diisopropylamide-Mediated Reactions of Imines, Unsaturated Esters, Epoxides, and Aryl Carbamates  

E-Print Network (OSTI)

Lithium Diisopropylamide-Mediated Reactions of Imines, Unsaturated Esters, Epoxides, and Aryl: Several reactions mediated by lithium diisopropylamide (LDA) with added hexamethylphos- phoramide (HMPA, and selectivities of organolithium reactions.1 A preponderance of what is known about solvation of lithium ions

Collum, David B.

168

Stochastic analysis of flow in a heterogeneous unsaturated-saturated system  

E-Print Network (OSTI)

of multiscale, nonstationary medium features. The unsaturated and saturated zones are coupled through the water table, whose position is random in randomly heterogeneous porous media. The presence of the water table zones [e.g., Dagan and Bresler, 1979; Bresler and Dagan, 1981; Andersson and Shapiro, 1983; Yeh et al

Zhang, Dongxiao

169

Estimation of Unsaturated Zone Traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test  

E-Print Network (OSTI)

of Las Vegas. The NTS is bordered by the Nellis Air Force Range and the Tonopah 5 #12;Test RangeEstimation of Unsaturated Zone Traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential

170

Dissipative particle dynamics simulation of fluid motion through an unsaturated fracture and fracture junction  

Science Conference Proceedings (OSTI)

Multiphase fluid motion in unsaturated fractures and fracture networks involves complicated fluid dynamics, which is difficult to model using grid-based continuum methods. In this paper, the application of dissipative particle dynamics (DPD), a relatively ... Keywords: Dissipative particle dynamics (DPD), Fracture, Fracture flow, Smoothed particle hydrodynamics (SPH), Weight functions

Moubin Liu; Paul Meakin; Hai Huang

2007-03-01T23:59:59.000Z

171

Results from the RACE (Ring ACceleration Experiment) Compact Torus Acceleration Experiment  

DOE Green Energy (OSTI)

RACE (Ring ACceleration Experiment) is a proof-of-principle experiment aimed at demonstrating acceleration of magnetically confined compact torus plasma rings to directed kinetic energies well in excess of their magnetic and thermal energies. In the course of the first year of operation the following have been observed: successful formation of rings in the RACE geometry; acceleration of rings with large forces, F/sub accelerate/ approx.F/sub equilibrium/ without apparent degradation of the ring structure; peak velocities of approx. =2.5 x 10/sup 8/ cm/sec; acceleration efficiency of >30% at speeds of 1.5 x 10/sup 8/ cm/sec inferred from trajectory and capacitor bank data; kinetic to magnetic energy ratios approx.10 were observed. Experiments in the near future will be aimed at confirmation of the mass/energy measurements by calorimetry and direct density measurements.

Hammer, J.H.; Hartman, C.W.; Eddleman, J.L.; Kusse, B.

1987-06-01T23:59:59.000Z

172

Apse Alignment of Narrow Eccentric Planetary Rings  

E-Print Network (OSTI)

The boundaries of the Uranian epsilon, alpha, and beta rings can be fitted by Keplerian ellipses. The pair of ellipses that outline a given ring share a common line of apsides. Apse alignment is surprising because the quadrupole moment of Uranus induces differential precession. We propose that rigid precession is maintained by a balance of forces due to ring self-gravity, planetary oblateness, and interparticle collisions. Collisional impulses play an especially dramatic role near ring edges. Pressure-induced accelerations are maximal near edges because there (1) velocity dispersions are enhanced by resonant satellite perturbations, and (2) the surface density declines steeply. Remarkably, collisional forces felt by material in the last 100 m of a 10 km wide ring can increase equilibrium masses up to a factor of 100. New ring surface densities are derived which accord with Voyager radio measurements. In contrast to previous models, collisionally modified self-gravity appears to allow for both negative and pos...

Chiang, E I

2000-01-01T23:59:59.000Z

173

Atlas and Catalog of Collisional Ring Galaxies  

E-Print Network (OSTI)

We present a catalog and imaging atlas of classical (collisional) RING galaxies distilled from the Arp-Madore Atlas of Southern Peculiar Galaxies and Associations and supplemented with other known RING galaxies from the published literature. The catalog lists the original host object, compiles available redshifts and presents newly determined positions for the central (target) galaxy and its nearest companion(s). 127 collisional RING systems are illustrated and their components identified. All of the RINGS have plausible colliders identified; many are radial-velocity confirmed companions. Finally, we make note of the existence of a rare sub-class of RING galaxies exemplified by AM 2136-492, double/concentric RING galaxies. These objects are predicted by numerical simulations, but they appear to be quite rare and/or short-lived in nature.

Madore, Barry F; Petrillo, Kristen

2009-01-01T23:59:59.000Z

174

Interferometric ring lasers and optical devices  

DOE Patents (OSTI)

Two ring diode lasers are optically coupled together to produce tunable, stable output through a Y-junction output coupler which may also be a laser diode or can be an active waveguide. These devices demonstrate a sharp peak in light output with an excellent side-mode-rejection ratio. The rings can also be made of passive or active waveguide material. With additional rings the device is a tunable optical multiplexer/demultiplexer. 11 figs.

Hohimer, J.P.; Craft, D.C.

1995-03-14T23:59:59.000Z

175

Interferometric ring lasers and optical devices  

DOE Patents (OSTI)

Two ring diode lasers are optically coupled together to produce tunable, stable output through a Y-junction output coupler which may also be a laser diode or can be an active waveguide. These devices demonstrate a sharp peak in light output with an excellent side-mode-rejection ratio. The rings can also be made of passive or active waveguide material. With additional rings the device is a tunable optical multiplexer/demultiplexer.

Hohimer, John P. (Albuquerque, NM); Craft, David C. (Albuquerque, NM)

1995-01-01T23:59:59.000Z

176

WELDED SEAL-RING VACUUM CLOSURES  

SciTech Connect

The development of bakeable high-vacuum flanges for the ORNL PIG Facility is reported. The general design approach for this type flange is to obtain a bakeable vacuum seal by first welding thin metal rings to a set of heavy metal flanges, and then edge-welding the rings together. This design sllows the option of O-ring sealing for nonbaked operation. A number of flange designs are discussed together with fabrication inspection, testing, and installation and maintenance information. (auth)

Michelson, C.

1959-08-21T23:59:59.000Z

177

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Wednesday, 28 April 2010 00:00 Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

178

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Wednesday, 28 April 2010 00:00 Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

179

The Brass Ring of Climate Modeling  

NLE Websites -- All DOE Office Websites (Extended Search)

Brass Ring of Climate Modeling For original submission and image(s), see ARM Research Highlights http:www.arm.govsciencehighlights Research Highlight Finding a simple way to...

180

REPORT OF THE STORAGE RING DESIGN GROUP  

E-Print Network (OSTI)

his the RF harmonic number. VRF the peak RF vol tage. l'Ssturn as 1 million volts: VRf We took the ring in race track

Peterson, J.M.

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Condenser for illuminating a ring field  

DOE Patents (OSTI)

A series of segments of a parent aspheric mirror having one foci at at a si-point source of radiation and the other foci at the radius of a ring field have all but one or all of their beams translated and rotated by sets of mirrors such that all of the beams pass through the real entrance pupil of a ring field camera about one of the beams and fall onto the ring field radius as a coincident image as an arc of the ring field.

Sweatt, William C. (Albuquerque, NM)

1994-01-01T23:59:59.000Z

182

Condenser for illuminating a ring field  

DOE Patents (OSTI)

A series of segments of a parent aspheric mirror having one foci at a point source of radiation and the other foci at the radius of a ring field have all but one or all of their beams translated and rotated by sets of mirrors such that all of the beams pass through the real entrance pupil of a ring field camera about one of the beams and fall onto the ring field radius as a coincident image as an arc of the ring field. 5 figs.

Sweatt, W.C.

1994-11-01T23:59:59.000Z

183

BOOSTER EXTRACTION, BOOSTER-TO-STORAGE RING TRANSPORT AND STORAGE RING INJECTION FOR THE ALS  

E-Print Network (OSTI)

Storage Ring Injection for the ALS M.S. Zisman March 1988Ring Injection for the ALS Michael S. Zisman Exploratoryon the design of the ALS injection system is presented. The

Zisman, M.S.

2010-01-01T23:59:59.000Z

184

Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler  

DOE Patents (OSTI)

A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings.

Kuklo, Thomas C. (Oakdale, CA)

1999-01-01T23:59:59.000Z

185

Concentric ring flywheel with hooked ring carbon fiber separator/torque coupler  

DOE Patents (OSTI)

A concentric ring flywheel with expandable separators, which function as torque couplers, between the rings to take up the gap formed between adjacent rings due to differential expansion between different radius rings during rotation of the flywheel. The expandable separators or torque couplers include a hook-like section at an upper end which is positioned over an inner ring and a shelf-like or flange section at a lower end onto which the next adjacent outer ring is positioned. As the concentric rings are rotated the gap formed by the differential expansion there between is partially taken up by the expandable separators or torque couplers to maintain torque and centering attachment of the concentric rings. 2 figs.

Kuklo, T.C.

1999-07-20T23:59:59.000Z

186

Mechanical support of a ceramic gas turbine vane ring  

SciTech Connect

An assembly for mounting a ceramic turbine vane ring onto a turbine support casing comprises a first metal clamping ring and a second metal clamping ring. The first metal clamping ring is configured to engage with a first side of a tab member of the ceramic turbine vane ring. The second metal clamping ring is configured to engage with a second side of the tab member such that the tab member is disposed between the first and second metal clamping rings.

Shi, Jun (Glastonbury, CT); Green, Kevin E. (Broad Brook, CT); Mosher, Daniel A. (Glastonbury, CT); Holowczak, John E. (South Windsor, CT); Reinhardt, Gregory E. (South Glastonbury, CT)

2010-07-27T23:59:59.000Z

187

On-sample water content measurement for a complete local monitoring in triaxial testing of unsaturated soils  

E-Print Network (OSTI)

To provide a complete local monitoring of the state of an unsaturated soil sample during triaxial testing, a local water content measurement device was adapted to a triaxial device comprising the measurement of local displacements (Hall effect transducers) and suction (High capacity transducer). Water content was locally monitored by means of a resistivity probe. The water content/resistivity calibration curves of an intact natural unsaturated loess from Northern France extracted by block sampling at two depths (1 and 3.3 m) were carefully determined, showing good accuracy and repeatability. The validity of two models giving the resistivity of unsaturated soils with respect to their water content was examined.

Munoz-Castelblanco, José; Pereira, Jean-Michel; Cui, Yu-Jun

2013-01-01T23:59:59.000Z

188

Hard x-ray response of a CdZnTe ring-drift detector  

Science Conference Proceedings (OSTI)

We present the results of an experimental study of a special type of CdZnTedetector of hard x and ? rays—a ring-drift detector. The device consists of a double ring electrode structure surrounding a central point anode with a guard plane surrounding the outer anode ring. The detector can be operated in two distinctively different modes of charge collection—pseudohemispherical and pseudodrift. We study the detector response profiles obtained by scanning the focused x-ray beam over the whole detector area

A. Owens; R. den Hartog; F. Quarati; V. Gostilo; V. Kondratjev; A. Loupilov; A. G. Kozorezov; J. K. Wigmore; A. Webb; E. Welter

2007-01-01T23:59:59.000Z

189

Enhanced ring lasers: a new measurement tool for Earth sciences  

Science Conference Proceedings (OSTI)

We report the progress in the technology of fabrication of large ring lasers that has resulted in an increase in instrumental rotation sensitivity by as much as a factor of 3, to {delta}{Omega} = 1.2 Multiplication-Sign 10{sup -11} rad s{sup -1} Hz{sup -1/2}, which makes the domain of changes in the angular velocity of Earth's rotation, {Delta}{Omega}/{Omega} Almost-Equal-To 10{sup -9}, accessible to a local rotation sensor. New studies show that the largest contribution to the observed deviation in sensor performance with respect to the computed shot noise limit is caused by the micro-seismic background activity of the Earth. Our efforts have been concentrated on the improvement of sensor stability, including correction of drift effects, which are caused by the aging of the laser gas, fixing scale factor instabilities induced by atmospheric pressure variations, and minimising the temperature variations resulting from corresponding adiabatic expansion and compression of the local air around the instrument. To achieve this, we have recently introduced a pressure-stabilising vessel with dimensions slightly larger than the ring laser apparatus, such that it encloses the entire structure. By monitoring the optical frequency in the ring laser cavity continuously and stabilising the scale factor in a closed loop system with the pressure-stabilising vessel, it has become possible to extend the range of sensor stability from the short term (1 - 3 days) to well into the mid-term regime (>40 days), and possibly even well beyond that. Once a sufficiently long timeseries of the ring laser data has been recorded, we will be able to define the range of temporal stability in more detail. The extension of the regime of stability gives access to geophysical signals at frequencies substantially lower than previously observable with ring lasers. (laser applications and other topics in quantum electronics)

Schreiber, K U; Kluegel, T; Wells, J.-P.; Holdaway, J; Gebauer, A; Velikoseltsev, A

2012-11-30T23:59:59.000Z

190

Orbital perturbations due to massive rings  

E-Print Network (OSTI)

We analytically work out the long-term orbital perturbations induced by a homogeneous circular ring of radius Rr and mass mr on the motion of a test particle in the cases (I): r > R_r and (II): r debris belts around the Earth, we do not restrict ourselves to the case in which the ring and the orbit of the perturbed particle lie just in the same plane. From the corrections to the standard secular perihelion precessions, recently determined by a team of astronomers for some planets of the Solar System, we infer upper bounds on mr for various putative and known annular matter distributions of natural origin (close circumsolar ring with R_r = 0.02-0.13 au, dust ring with R_r = 1 au, minor asteroids, Trans-Neptunian Objects). We find m_r <= 1.4 10^-4 m_E (circumsolar ring with R_r = 0.02 au), m_r <= 2.6 10^-6 m_E (circumsolar ring with R_r = 0.13 au), m_r <= 8.8 10^-7 m_E (ring with R_r = 1 au), m_r <= 7.3 10^-12 M_S (asteroidal ring with R_r = 2.80 au), m_r <= 1.1 <= 10^-11 M_S (asteroidal ring with R_r = 3.14 au), m_r <= 2.0 10^-8 M_S (TNOs ring with R_r = 43 au). In principle, our analysis is valid both for baryonic and non-baryonic Dark Matter distributions.

Lorenzo Iorio

2012-01-25T23:59:59.000Z

191

Preliminary 3-D site-scale studies of radioactive colloid transort in the unsaturated zone at Yucca Mountain, Nevada  

E-Print Network (OSTI)

into drifts at Yucca Mountain. ” J. Contam. Hydrol. , 38(1–pneumatic response at Yucca Mountain, Nevada. J. Contam.unsaturated zone model of Yucca Mountain, Nevada. J. Contam.

Moridis, G.J.; Hu, Q.; Wu, Y.-S.; Bodvarsson, G.S.

2001-01-01T23:59:59.000Z

192

Lipid Oxidation PathwaysChapter 3 Competitive Oxidation between a-Tocopherol and Unsaturated Fatty Acids at Thermoxidation Conditions  

Science Conference Proceedings (OSTI)

Lipid Oxidation Pathways Chapter 3 Competitive Oxidation between a-Tocopherol and Unsaturated Fatty Acids at Thermoxidation Conditions Health Nutrition Biochemistry eChapters Health - Nutrition - Biochemistry Downloadable pd

193

Models for Unsaturated Hydraulic Conductivity Based on Truncated Lognormal Pore-size Distributions  

E-Print Network (OSTI)

We develop a closed-form three-parameter model for unsaturated hydraulic conductivity associated with a three-parameter lognormal model of moisture retention, which is based on lognormal grainsize distribution. The derivation of the model is made possible by a slight modification to the theory of Mualem. We extend the three-parameter lognormal distribution to a four-parameter model that also truncates the pore size distribution at a minimum pore radius. We then develop the corresponding four-parameter model for moisture retention and the associated closed-form expression for unsaturated hydraulic conductivity. The four-parameter model is fitted to experimental data, similar to the models of Kosugi and van Genuchten. The proposed four-parameter model retains the physical basis of Kosugi's model, while improving fit to observed data especially when simultaneously fitting pressure-saturation and pressure-conductivity data.

Malama, Bwalya

2013-01-01T23:59:59.000Z

194

Advanced Conceptual Models for Unsaturated and Two-Phase Flow in Fractured Rock  

DOE Green Energy (OSTI)

This project was initiated in FY03. As of December 2003, we have accomplished the following: (1) We conducted a more detailed evaluation of the preliminary experiments used to develop our investigative approach. In those experiments, water was invaded at a variety of flow rates into an air-filled, two dimensional analog fracture network. Results demonstrated the critical control that fracture intersections place on two-phase flow in fracture networks. At low flows, capillary and gravitational forces combined to create a narrow pulsing flow structure that spanned the system vertically. At higher flows, viscous forces acted to remove the pulsation; however, the flow structure remained narrow. The intersections acted to impose a narrow ''slender ladder'' structure on the flowing phase that did not expand with depth, but instead remained focused. A manuscript documenting this effort has been published in Water Resources Research [Glass et al., 2003a]. (2) We initiated a collaborative relationship with a research group at Seoul National University. This group, which is led by Dr. Kang-Kun Lee is also using a combined experimental numerical approach to consider DNAPL migration in fracture networks. They are particularly interested in the influence of ambient groundwater flows, making their work complementary to ours. The first fruit of that collaboration is an article demonstrating that modification of an Invasion Percolation algorithm to include gravity and the first-order effects of viscous forces shows good agreement with physical experiments in a simplistic fracture network. Results were published in Geophysical Research Letters [Ji et al., 2003a]. (3) We carried out an extensive review of models for fracture networks. These include models developed from observations of networks on outcrops at several scales and stochastic models that are prevalent in the literature from the 1980s to very recent developments. The results of this review were included as par t of a review paper co-authored by Rajaram, which was submitted to Reviews in Geophysics [Molz et al., in press]. (4) We prepared a manuscript based on previous work that will be used to support the development of our new conceptual model(s) for transport in fractured rock. Eight experiments were conducted to evaluate the repeatability of flow under nearly identical conditions and to characterize general patterns in flow behavior. Collected data revealed that flow generally converged to a single fracture in the bottom row of blocks. Periods of pathway switching were observed to be more common than periods with steady, constant flow pathways. We noted the importance of fracture intersections for integrating uniform flow and discharging a ''fluid cascade'', where water advances rapidly to the next capillary barrier creating a stop and start advance of water through the network. The results of this simple experiment suggest that the interaction of multiple fracture intersections in a network creates flow behavior not generally recognized in popular conceptual and numerical models. A manuscript documenting this effort has been accepted for publication in Vadose Zone Journal [Wood et al., 2003]. (5) Slender transport pathways have been found in laboratory and field experiments within unsaturated fractured rock. We considered the simulation of such structures with a Modified form of Invasion Percolation (MIP). Results show that slender pathways form in fracture networks for a wide range of expected conditions, can be maintained when subsequent matrix imbibition is imposed, and may arise even in the context of primarily matrix flow due to the action of fractures as barriers to inter-matrix block transport. A manuscript documenting this effort has been submitted to Geophysical Research Letters [Glass et al., 2003b].

Rajaram, Harihar

2003-06-01T23:59:59.000Z

195

Study of a 'Relaxed' ALS Storage Ring Lattice  

E-Print Network (OSTI)

Relaxed' ALS Storage Ring Lattice R. Keller, E. Forest, H.RELAXED' ALS STORAGE RING LATTICE' R. Keller, E. Forest, H.of the ring wilh standard lattice is satisractory. Acknowlc;

Keller, R.

2010-01-01T23:59:59.000Z

196

Conservation Laws for Coupled Hydro-mechanical Processes in Unsaturated Porous Media: Theory and Implementation  

Science Conference Proceedings (OSTI)

We develop conservation laws for coupled hydro-mechanical processes in unsaturated porous media using three-phase continuum mixture theory. From the first law of thermodynamics, we identify energy-conjugate variables for constitutive modeling at macroscopic scale. Energy conjugate expressions identified relate a certain measure of effective stress to the deformation of the solid matrix, the degree of saturation to the matrix suction, the pressure in each constituent phase to the corresponding intrinsic volume change of this phase, and the seepage forces to the corresponding pressure gradients. We then develop strong and weak forms of boundary-value problems relevant for 3D finite element modeling of coupled hydro-mechanical processes in unsaturated porous media. The paper highlights a 3D numerical example illustrating the advances in the solution of large-scale coupled finite element systems, as well as the challenges in developing more predictive tools satisfying the basic conservation laws and the observed constitutive responses for unsaturated porous materials.

Borja, R I; White, J A

2010-02-19T23:59:59.000Z

197

207_06 Structural Analysis of Unsaturated Fatty Acid Methyl Ester Isomers with Acetonitrile Covalent  

Science Conference Proceedings (OSTI)

AOCS Press, Urbana, IL 61802 ©2006 by AOCS Press. All rights reserved. No part of this PDF may be repro-

198

FREE RESOLUTIONS OVER SHORT LOCAL RINGS LUCHEZAR L. AVRAMOV, SRIKANTH B. IYENGAR, AND LIANA M. SEGA  

E-Print Network (OSTI)

FREE RESOLUTIONS OVER SHORT LOCAL RINGS LUCHEZAR L. AVRAMOV, SRIKANTH B. IYENGAR, AND LIANA M. S¸EGA To the memory of our friend and colleague Anders Frankild. Abstract. The structure of minimal free resolutions This paper is concerned with the structure of minimal free resolutions of finite (that is, finitely generated

Sega, Liana - Department of Mathematics and Statistics, University of Missouri

199

Dipolar bosons on an optical lattice ring  

Science Conference Proceedings (OSTI)

We consider an ultrasmall system of polarized bosons on an optical lattice with a ring topology, interacting via long-range dipole-dipole interactions. Dipoles polarized perpendicular to the plane of the ring reveal sharp transitions between different density-wave phases. As the strength of the dipolar interactions is varied, the behavior of the transitions is first-order-like. For dipoles polarized in the plane of the ring, the transitions between possible phases show pronounced sensitivity to the lattice depth. The abundance of possible configurations may be useful for quantum-information applications.

Maik, Michal [Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagiellonski, ulica Reymonta 4, PL-30-059 Krakow (Poland); Buonsante, Pierfrancesco [Dipartimento di Fisica, Universita degli Studi di Parma, Viale G.P. Usberti n.7/A, IT-43100 Parma (Italy); Vezzani, Alessandro [Centro S3, CNR Istituto di Nanoscienze, via Campi 213/a, IT-41100 Modena (Italy); Dipartimento di Fisica, Universita degli Studi di Parma, Viale G.P. Usberti n.7/A, 43100 Parma (Italy); Zakrzewski, Jakub [Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagiellonski, ulica Reymonta 4, PL-30-059 Krakow (Poland); Mark Kac Complex Systems Research Center, Uniwersytet Jagiellonski, ulica Reymonta 4, PL-30-059 Krakow (Poland)

2011-11-15T23:59:59.000Z

200

Fiberoptics-Based Instrumentation for Storage Ring Beam Diagnostics  

E-Print Network (OSTI)

FIBEROPTICS-BASED INSTRUMENTATION FOR STORAGE RING BEAMbeam diagnostic instrumentation that measures longitudinalet al. , “Fiberoptics-based Instrumentation for Storage Ring

Byrd, John M.; De Santis, Stefano; Yin, Yan

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Electron beam depolarization in a damping ring  

SciTech Connect

Depolarization of a polarized electron beam injected into a damping ring is analyzed by extending calculations conventionally applied to proton synchrotrons. Synchrotron radiation in an electron ring gives rise to both polarizing and depolarizing effects. In a damping ring, the beam is stored for a time much less than the time for self polarization. Spin flip radiation may therefore be neglected. Synchrotron radiation without spin flips, however, must be considered as the resonance strength depends on the vertical betatron oscillation amplitude which changes as the electron beam is radiation damped. An expression for the beam polarization at extraction is derived which takes into account radiation damping. The results are applied to the electron ring at the Stanford Linear Collider and are compared with numerical matrix formalisms.

Minty, M.

1993-04-01T23:59:59.000Z

202

Power Ring LLC | Open Energy Information  

Open Energy Info (EERE)

Ring LLC Ring LLC Jump to: navigation, search Name Power Ring LLC Place Goleta, California Zip 93117 Product Power Ring is a power storage technology developer working on technology developed by parent firm LaunchPoint Technologies. Coordinates 34.435682°, -119.824105° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":34.435682,"lon":-119.824105,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

203

Low thermal expansion seal ring support  

DOE Patents (OSTI)

Today, the trend is to increase the temperature of operation of gas turbine engines. To cool the components with compressor discharge air, robs air which could otherwise be used for combustion and creates a less efficient gas turbine engine. The present low thermal expansion sealing ring support system reduces the quantity of cooling air required while maintaining life and longevity of the components. Additionally, the low thermal expansion sealing ring reduces the clearance "C","C'" demanded between the interface between the sealing surface and the tip of the plurality of turbine blades. The sealing ring is supported by a plurality of support members in a manner in which the sealing ring and the plurality of support members independently expand and contract relative to each other and to other gas turbine engine components.

Dewis, David W. (San Diego, CA); Glezer, Boris (Del Mar, CA)

2000-01-01T23:59:59.000Z

204

On the Stability of Oceanic Rings  

Science Conference Proceedings (OSTI)

Oceanic rings tend to have length scales larger than the deformation radius and also to he long-lived. This latter characteristic, in view of the former, is particularly curious as many quasigeostrophic and primitive equation simulations suggest ...

William K. Dewar; Peter D. Killworth

1995-06-01T23:59:59.000Z

205

The Price of Atomic Selfish Ring Routing?  

E-Print Network (OSTI)

‡Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080 , ... The ring topology is a fundamental topology that is frequently encountered in ...... [9] A. Czumaj, Selfish routing on the Internet, in Handbook of Scheduling: ...

206

Dark matter axions and caustic rings  

SciTech Connect

This report contains discussions on the following topics: the strong CP problem; dark matter axions; the cavity detector of galactic halo axions; and caustic rings in the density distribution of cold dark matter halos.

Sikivie, P.

1997-11-01T23:59:59.000Z

207

Latest on polarization in electron storage rings  

SciTech Connect

The field of beam polarization in electron storage rings is making rapid progress in recent several years. This report is an attempt to summarize some of these developments concerning how to produce and maintain a high level of beam polarization. Emphasized will be the ideas and current thoughts people have on what should and could be done on electron rings being designed at present such as HERA, LEP and TRISTAN. 23 references.

Chao, A.W.

1983-01-01T23:59:59.000Z

208

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

209

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

210

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

211

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

212

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

213

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on biological molecules using adenosine triphosphate (ATP) as chemical fuel. A specialized class of ring-shaped motor proteins, hexameric helicases, can unwind DNA strands and perform large-scale manipulations of single-stranded nucleic acids in processes such as DNA replication, DNA repair, and gene expression. To understand how certain hexameric helicases walk with directional polarity along single-stranded nucleic acids, Berkeley researchers used x-ray crystallography at the ALS to solve the structure of a hexameric helicase, the Rho transcription termination factor (from E. coli), bound to both ATP mimics and an RNA substrate. The results showed that Rho functions like a rotary engine: as the motor spins, it pulls RNA strands through its interior. Interestingly, the rotary firing order of the motor is biased so that the Rho protein can walk in only one direction along the RNA chain.

214

ON -DEDEKIND RINGS AND -KRULL RINGS DAVID F. ANDERSON AND AYMAN BADAWI  

E-Print Network (OSTI)

domains and Krull domains. Let H = {R | R is a commutative ring with 1 = 0 and Nil(R) is a divided prime ideal of R}. Let R H, T(R) be the total quotient ring of R, and set : T(R) - RNil(R) such that (a/b) = a/b for every a R and b R \\ Z(R). Then is a ring homomorphism from T(R) into RNil(R

Badawi, Ayman

215

Analysis, modeling and simulation of ring resonators and their applications to filters and oscillators  

E-Print Network (OSTI)

Microstrip ring circuits have been extensively studied in the past three decades. A magnetic-wall model has been commonly used to analyze these circuits. Unlike the conventional magnetic-wall model, a simple transmission-line model, unaffected by boundary conditions, is developed to calculate the frequency modes of ring resonators of any general shape such as annular, square, or meander ring resonators. The new model can be used to extract equivalent lumped element circuits and unloaded Qs for both closed- and open-loop ring resonators. Several new bandpass filter structures, such as enhanced coupling, slow-wave, asymmetric-fed with two transmission zeros, and orthogonal direct-fed, have been proposed. These new proposed filters provide advantages of compact size, low insertion loss, and high selectivity. Also, an analytical technique is used to analyze the performance of the filters. The measured results show good agreement with the simulated results. A compact elliptic-function lowpass filter using microstrip stepped impedance hairpin resonators has been developed. The prototype filters are synthesized from the equivalent circuit model using available element-value tables. The filters are evaluated by experiment and simulation with good agreement. This simple equivalent circuit model provides a useful method to design and understand this type of filters and other relative circuits.Finally, a tunable feedback ring resonator oscillator using a voltage controlled piezoelectric transducer is introduced. The new oscillator is constructed by a ring resonator using a pair of orthogonal feed lines as a feedback structure. The ring resonator with two orthogonal feed lines can suppress odd modes and operate at even modes. A voltage controlled piezoelectric transducer is used to vary the resonant frequency of the ring resonator. This tuned oscillator operating at high oscillation frequency can be used in many wireless and sensor systems.

Hsieh, Lung-Hwa

2006-05-01T23:59:59.000Z

216

On the Structure of the Fusion Ideal  

E-Print Network (OSTI)

On the Structure of the Fusion Ideal 4. Bouwknegt, P. ,of Wess-Zumino-Witten fusion rings. Rev. Math. Phys.A conjectural presentation of fusion algebras. Preprint,

Douglas, Christopher L.

2009-01-01T23:59:59.000Z

217

Stable CSR in storage rings: A model  

SciTech Connect

A comprehensive historical view of the work done on coherent synchrotron radiation (CSR) in storage rings is given in reference [1]. Here we want just to point out that even if the issue of CSR in storage rings was already discussed over 50 years ago, it is only recently that a considerable number of observations have been reported. In fact, intense bursts of coherent synchrotron radiation with a stochastic character were measured in the terahertz frequency range, at several synchrotron light source storage rings [2-8]. It has been shown [8-11], that this bursting emission of CSR is associated with a single bunch instability, usually referred as microbunching instability (MBI), driven by the fields of the synchrotron radiation emitted by the bunch itself. Of remarkably different characteristics was the CSR emission observed at BESSY II in Berlin, when the storage ring was tuned into a special low momentum compaction mode [12, 13]. In fact, the emitted radiation was not the quasi-random bursting observed in the other machines, but a powerful and stable flux of broadband CSR in the terahertz range. This was an important result, because it experimentally demonstrated the concrete possibility of constructing a stable broadband source with extremely high power in the terahertz region. Since the publication of the first successful experiment using the ring as a CSR source [14], BESSY II has regular scheduled user s shifts dedicated to CSR experiments. At the present time, several other laboratories are investigating the possibility of a CSR mode of operation [15-17] and a design for a new ring optimized for CSR is at an advanced stage [18]. In what follows, we describe a model that first accounts for the BESSY II observations and then indicates that the special case of BESSY II is actually quite general and typical when relativistic electron storage rings are tuned for short bunches. The model provides a scheme for predicting and optimizing the performance of ring-based CSR sources with a stable broadband photon flux in the terahertz region of up to {approx} 9 orders of magnitude larger than in existing ''conventional'' storage rings. Such a scheme is of interest not only for the design of new sources but also for the evaluation and optimization of the CSR performance in existing electron storage rings. The presented results are mainly based on reference [19].

Sannibale, Fernando; Byrd, John M.; Loftsdottir, Agusta; Venturini, Marco; Abo-Bakr, Michael; Feikes, Jorge; Holldack, Karsten; Kuske, Peter; Wustefeld, Godehart; Hubers, Heinz-Willerm; Warnock, Robert

2005-01-03T23:59:59.000Z

218

Radon transform on a space over a residue class ring  

Science Conference Proceedings (OSTI)

The functions on a space of dimension N over the residue class ring Z{sub n} modulo n that are invariant with respect to the group GL(N,Z{sub n}) form a commutative convolution algebra. We describe the structure of this algebra and find the eigenvectors and eigenvalues of the operators of multiplication by elements of this algebra. The results thus obtained are applied to solve the inverse problem for the hyperplane Radon transform on Z{sup N}{sub n}. Bibliography: 2 titles.

Molchanov, Vladimir F [Tambov State University, Tambov (Russian Federation)

2012-05-31T23:59:59.000Z

219

MIGRATION OF SMALL MOONS IN SATURN's RINGS  

SciTech Connect

The motions of small moons through Saturn's rings provide excellent tests of radial migration models. In theory, torque exchange between these moons and ring particles leads to radial drift. We predict that moons with Hill radii r {sub H} {approx} 2-24 km should migrate through the A ring in 1000 yr. In this size range, moons orbiting in an empty gap or in a full ring eventually migrate at the same rate. Smaller moons or moonlets-such as the propellers-are trapped by diffusion of disk material into corotating orbits, creating inertial drag. Larger moons-such as Pan or Atlas-do not migrate because of their own inertia. Fast migration of 2-24 km moons should eliminate intermediate-size bodies from the A ring and may be responsible for the observed large-radius cutoff of r {sub H} {approx} 1-2 km in the size distribution of the A ring's propeller moonlets. Although the presence of Daphnis (r {sub H} Almost-Equal-To 5 km) inside the Keeler gap challenges this scenario, numerical simulations demonstrate that orbital resonances and stirring by distant, larger moons (e.g., Mimas) may be important factors. For Daphnis, stirring by distant moons seems the most promising mechanism to halt fast migration. Alternatively, Daphnis may be a recent addition to the ring that is settling into a low inclination orbit in {approx}10{sup 3} yr prior to a phase of rapid migration. We provide predictions of observational constraints required to discriminate among possible scenarios for Daphnis.

Bromley, Benjamin C. [Department of Physics and Astronomy, University of Utah, 115 S 1400 E, Rm 201, Salt Lake City, UT 84112 (United States)] [Department of Physics and Astronomy, University of Utah, 115 S 1400 E, Rm 201, Salt Lake City, UT 84112 (United States); Kenyon, Scott J., E-mail: bromley@physics.utah.edu, E-mail: skenyon@cfa.harvard.edu [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-02-20T23:59:59.000Z

220

Structure  

NLE Websites -- All DOE Office Websites (Extended Search)

Structure Structure functions 1 NOTE: THE FIGURES IN THIS SECTION ARE INTENDED TO SHOW THE REPRESENTATIVE DATA. THEY ARE NOT MEANT TO BE COMPLETE COMPILATIONS OF ALL THE WORLD'S RELIABLE DATA. Q 2 (GeV 2 ) F 2 (x,Q 2 ) * 2 i x H1 ZEUS BCDMS E665 NMC SLAC 10 -3 10 -2 10 -1 1 10 10 2 10 3 10 4 10 5 10 6 10 7 10 8 10 9 10 -1 1 10 10 2 10 3 10 4 10 5 10 6 Figure 16.6: The proton structure function F p 2 measured in electromagnetic scattering of positrons on protons (collider experiments ZEUS and H1), in the kinematic domain of the HERA data, for x > 0.00006 (cf. Fig. 16.9 for data at smaller x and Q 2 ), and for electrons (SLAC) and muons (BCDMS, E665, NMC) on a fixed target. Statistical and systematic errors added in quadrature are shown. The data are plotted as a function of Q 2 in bins of fixed x. Some points have been slightly offset in Q 2 for clarity. The ZEUS binning in x is used in this plot; all other data are rebinned to the x values of

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

RINGS OF DIFFERENTIAL OPERATORS ON CLASSICAL RINGS OF INVARIANTS T. Levasseur and J.T. Stafford  

E-Print Network (OSTI)

RINGS OF DIFFERENTIAL OPERATORS ON CLASSICAL RINGS OF INVARIANTS by T. Levasseur and J.T. Stafford.3)). For the Received by the editors February 8, 1988 1 #12;2 T. LEVASSEUR and J. T. STAFFORD purposes = R . #12;4 T. LEVASSEUR and J. T. STAFFORD Some remarks on this theorem are in order. First, note

Levasseur, Thierry

222

RINGS OF DIFFERENTIAL OPERATORS ON CLASSICAL RINGS OF INVARIANTS T. Levasseur and J.T. Stafford  

E-Print Network (OSTI)

RINGS OF DIFFERENTIAL OPERATORS ON CLASSICAL RINGS OF INVARIANTS by T. Levasseur and J.T. Stafford February 8, 1988 1 #12; 2 T. LEVASSEUR and J. T. STAFFORD purposes of this introduction we merely note over the subring R = U(sp(2n))=J(k) . Moreover D(A) Z=2Z = R . #12; 4 T. LEVASSEUR and J. T. STAFFORD

Levasseur, Thierry

223

TOUGH: a numerical model for nonisothermal unsaturated flow to study waste canister heating effects  

Science Conference Proceedings (OSTI)

The physical processes modeled and the mathematical and numerical methods employed in a simulator for non-isothermal flow of water, vapor, and air in permeable media are briefly summarized. The simulator has been applied to study thermo-hydrological conditions in the near vicinity of high-level nuclear waste packages emplaced in unsaturated rocks. The studies reported here specifically address the question whether or not the waste canister environment will dry up in the thermal phase. 13 references, 8 figures, 2 tables.

Pruess, K.; Wang, J.S.Y.

1983-12-01T23:59:59.000Z

224

Evolution of the conceptual model of unsaturated zone hydrology at yucca mountain, nevada  

SciTech Connect

Yucca Mountain is an arid site proposed for consideration as the United States' first underground high-level radioactive waste repository. Low rainfall (approximately 170 mm/yr) and a thick unsaturated zone (500-1000 m) are important physical attributes of the site because the quantity of water likely to reach the waste and the paths and rates of movement of the water to the saturated zone under future climates would be major factors in controlling the concentrations and times of arrival of radionuclides at the surrounding accessible environment. The framework for understanding the hydrologic processes that occur at this site and that control how quickly water will penetrate through the unsaturated zone to the water table has evolved during the past 15 yr. Early conceptual models assumed that very small volumes of water infiltrated into the bedrock (0.5-4.5 mm/yr, or 2-3 percent of rainfall), that much of the infiltrated water flowed laterally within the upper nonwelded units because o f capillary barrier effects, and that the remaining water flowed down faults with a small amount flowing through the matrix of the lower welded, fractured rocks. It was believed that the matrix had to be saturated for fractures to show. However, accumulating evidence indicated that infiltration rates were higher than initially estimated, such as infiltration modeling based on neutron borehole data, bomb-pulse isotopes deep in the mountain, perched water analyses and thermal analyses. Mechanisms supporting lateral diversion did not apply at these higher fluxes, and the flux calculated in the lower welded unit exceeded the conductivity of the matrix, implying vertical flow of water into the high permeability fractures of the potential repository host rock, and disequilibrium between matrix and fracture water potentials. The development of numerical modeling methods and parameter values evolved concurrently with the conceptual model in order to account for the observed field data, particularly fracture flow deep in the unsaturated zone. This paper presents the history of the evolution of conceptual models of hydrology and numerical models of unsaturated zone flow at Yucca Mountain, Nevada (Flint, A.L., Flint, L.E., Kwicklis, E.M., Bodvarsson, G.S., Fabryka-Martin, J.M., 2001. Hydrology of Yucca Mountain. Reviews of Geophysics in press). This retrospective is the basis for recommendations for optimizing the efficiency with which a viable and robust conceptual model can be developed for a complex site. (C) 2001 Elsevier Science B.V. All rights reserved. [References: 87

Flint, A. L.; Flint, L. E.; Bodvarsson, G. S.; Kwicklis, E. M.; Fabryka-Martin, J.

2001-02-01T23:59:59.000Z

225

Experimental Results of the Small Isochronous Ring  

DOE Green Energy (OSTI)

The Small Isochronous Ring (SIR) has been in operation since December 2003. The main purpose of this ring, developed and built at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU), is to simulate the dynamics of intense beams in large accelerators. To observe the same effects, the beam power needed in SIR is orders of magnitude lower and the time scale is much longer than in the full scale machines. These differences simplify the design and operation of the accelerator. The ring measurements can be used to validate the results of space charge codes. After a variable number of turns, the injected hydrogen bunch (with energies up to 30 keV) is extracted and its longitudinal profile is measured using a fast Faraday cup. We present a summary of the design, the results of the first six months of operation and the comparison with selected space charge codes.

Felix Martin; Richard York; Juan Rodriguez; Eduard Pozdeyev

2004-06-01T23:59:59.000Z

226

Photoneutron production inside the APS Storage Ring  

NLE Websites -- All DOE Office Websites (Extended Search)

4 4 Neutron Fluence Estimates Inside the APS Storage Ring During Normal Operation P.K. Job and J. Alderman Advanced Photon Source Argonne National Laboratory April 2002 Neutron Fluence Estimates Inside the APS Storage Ring During Normal Operation P.K. Job and J. Alderman Advanced Photon Source Argonne National Laboratory April 2002 Introduction In an electron storage ring, neutrons are generated as a result of the electron beam interaction with high-Z materials, such as scrapers and collimators [1]. When the energy of the incident electron beam is sufficiently high, it can produce high-energy photons, which subsequently interact with a nucleus, resulting in the emission of nucleons. This interaction is known as a photonuclear interaction. For photons with energies above the

227

Beam Diagnostics of the Small Isochronous Ring  

DOE Green Energy (OSTI)

The purpose of this paper is to describe the beam diagnostic systems in the Small Isochronous Ring (SIR) developed and built at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). SIR is a small-scale experiment that simulates the dynamics of intense beams in large accelerators. A 20 to 30 keV hydrogen or deuterium ion bunch is injected in the ring, extracted after a variable number of turns and its longitudinal profile is studied. Some of the diagnostic tools available in SIR include an emittance measurement system in the injection line, scanning wires in different sections of the ring, phosphor screens at the injection and extraction points and a fast Faraday cup in the extraction line. The design of these systems and the kind of beam information they provide are discussed in detail.

Felix Marti; Eduard Pozdeyev

2004-07-01T23:59:59.000Z

228

Control System of the Small Isochronous ring  

DOE Green Energy (OSTI)

The purpose of this paper is to describe the control system of the Small Isochronous Ring (SIR) developed and built at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU). SIR is a small-scale experiment that simulates the dynamics of intense beams in large accelerators. A 20 to 30 keV hydrogen or deuterium ion bunch is injected in the ring, extracted after a variable number of turns and its longitudinal profile is studied. Information about the electronics used and software written to control different injection line, ring and extraction line elements is included. Some of these elements are magnets, electrostatic quadrupoles, electric and magnetic correctors, scanning wires, emittance measurement system, chopper and a fast Faraday cup.

Felix Marti; Eduard Pozdeyev

2004-07-01T23:59:59.000Z

229

CHALLENGES FOR THE SNS RING ENERGY UPGRADE  

Science Conference Proceedings (OSTI)

The Oak Ridge Spallation Neutron Source accumulator ring presently operates at a beam power of about 1 MW with a beam energy of about 910 MeV. A power upgrade is planned to increase the beam energy to 1.3 GeV. For the accumulator ring this mostly involves modifications to the injection and extraction sections. A variety of modifications to the existing injection section were necessary to achieve 1 MW, and the tools developed and the lessons learned from this work are now being applied to the design of the new injection section. This paper will discuss the tools and the lessons learned, and also present the design and status of the upgrades to the accumulator ring.

Plum, Michael A [ORNL; Gorlov, Timofey V [ORNL; Holmes, Jeffrey A [ORNL; Hunter, W Ted [ORNL; Roseberry, Jr., R Tom [ORNL; Wang, Jian-Guang [ORNL

2012-01-01T23:59:59.000Z

230

Unsaturated flow and transport through fractured rock related to high-level waste repositories; Final report, Phase 3  

SciTech Connect

Research results are summarized for a US Nuclear Regulatory Commission contract with the University of Arizona focusing on field and laboratory methods for characterizing unsaturated fluid flow and solute transport related to high-level radioactive waste repositories. Characterization activities are presented for the Apache Leap Tuff field site. The field site is located in unsaturated, fractured tuff in central Arizona. Hydraulic, pneumatic, and thermal characteristics of the tuff are summarized, along with methodologies employed to monitor and sample hydrologic and geochemical processes at the field site. Thermohydrologic experiments are reported which provide laboratory and field data related to the effects conditions and flow and transport in unsaturated, fractured rock. 29 refs., 17 figs., 21 tabs.

Evans, D.D.; Rasmussen, T.C. [Arizona Univ., Tucson, AZ (USA). Dept. of Hydrology and Water Resources

1991-01-01T23:59:59.000Z

231

Recent Studies in ATF Damping Ring  

Science Conference Proceedings (OSTI)

The damping ring of the Accelerator Test Facility (ATF) at KEK is designed to produce an extremely small vertical emittance beam as a test accelerator for future linear colliders. Development of various system and components for ILC (International Linear Collider) is also an important purpose of this facility. Though most of the beam time of ATF is dedicated to the final focus test project (ATF2), some studies have been performed in the damping ring. Here we report recent effort of low emittance tuning and multi-bunch extraction test of the fast kicker.

Araki, S.; Hayano, H.; Kubo, K.; Kuroda, S.; Naito, T.; Okugi, T.; Terunuma, N.; Urakawa, J.; /KEK, Tsukuba; Woodley, M.D.; /SLAC; Wolski, A.; Panagiotidis, K.; /Liverpool U. /Cockcroft Inst. Accel. Sci. Tech.

2012-04-24T23:59:59.000Z

232

MODELING U TRANSPORT IN THE UNSATURATED ZONE AT PENA BLANCA, MEXICO  

SciTech Connect

We present a quantitative model to describe transport of radionuclides underground. Applicable to unsaturated (vadose) as well as saturated (phreatic) layers, the model provides constraints on the in-situ migratory behavior of radioisotopes in dissolved and colloidal pools of a groundwater system. It shows, for examples, that uranium in water percolating through the vadose zone will have its concentration and ratio {sup 234}U/{sup 238}U linearly correlated under the ideal condition of a constant removal of the two U isotopes from vadose-zone solids. The intercept and slope of the linearity serve to constrain removal rates of the two uranium isotopes from solids to the solution through dissolution and alpha recoil. The model also allows estimation of the fluid transit time in the vadose zone. At Pena Blanca, the uneven distribution of rainfall between winter (wet) and summer (dry) results in a conspicuous seasonal variability in uranium removal rate, hence dissolved uranium signals, within the unsaturated zone. Our data indicate a much higher uranium dissolution rate during the dry season than during the wet season, possibly reflecting a condition of increased oxygenation in the zone during the dry period.

T.L. Ku; S. Luo; M. Murrell; S. Goldstein

2005-07-01T23:59:59.000Z

233

Investigation of Episodic Flow from Unsaturated Porous Media into a Macropore  

DOE Green Energy (OSTI)

Th e recent literature contains numerous observations of episodic or intermittent fl ow in unsaturated flow systems under both constant fl ux and ponded boundary conditions. Flow systems composed of a heterogeneous porous media, as well as discrete fracture networks, have been cited as examples of systems that can exhibit episodic fl ow. Episodic outfl ow events are significant because relatively large volumes of water can move rapidly through an unsaturated system, carrying water and contaminants to depth greatly ahead of a wetting front predicted by a one-dimensional, gravity-driven diff usive infiltration model. In this study, we model the behavior of water flow through a sand column underlain by an impermeable-walled macropore. Relative permeability and capillary pressure relationships were developed that capture the complex interrelationships between the macropore and the overlying porous media that control fl ow out of the system. The potential for episodic flow is assessed and compared to results of conventional modeling approaches and experimental data from the literature. Model results using coupled matrix–macropore relative permeability and capillary pressure relationships capture the behavior observed in laboratory experiments remarkably well, while simulations using conventional relative permeability and capillary pressure functions fail to capture some of the observed fl ow dynamics. Capturing the rapid downward movement of water suggests that the matrix-macropore capillary pressure and relative permeability functions developed have the potential to improve descriptions of fl ow and transport processes in heterogeneous, variably saturated media.

R. K. Podgorney; J. P. Fairley

2008-02-01T23:59:59.000Z

234

Nuclear-waste isolation in the unsaturated zone of arid regions  

Science Conference Proceedings (OSTI)

The vadose zone in arid regions is considered as a possible environment for geologic isolation of nuclear waste. There are several topographic and lithologic combinations in the vadose zone of arid regions that may lend themselves to waste isolation considerations. In some cases, topographic highs such as mesas and interbasin ranges - comprised of several rock types, may contain essentially dry or partially saturated conditions favorable for isolation. The adjacent basins, especially in the far western and southwestern US, may have no surface or subsurface hydrologic connections with systems ultimately leading to the ocean. Some rock types may have the favorable characteristics of very low permeability and contain appropriate minerals for the strong chemical retardation of radionuclides. Environments exhibiting these hydrologic and geochemical attributes are the areas underlain by tuffaceous rocks, relatively common in the Basin and Range geomorphic province. Adjacent valley areas, where tuffaceous debris makes up a significant component of valley fill alluvium, may also contain thick zones of unsaturated material, and as such also lend themselves to strong consideration as respository environments. This paper summarizes the aspects of nuclear waste isolation in unsaturated regimes in alluvial-filled valleys and tuffaceous rocks of the Basin and Range province.

Wollenberg, H.A.; Wang, J.S.Y.; Korbin, G.

1982-05-01T23:59:59.000Z

235

An Integrated Modeling Analysis of Unsaturated Flow Patterns inFractured Rock  

Science Conference Proceedings (OSTI)

Characterizing percolation patterns in unsaturated zones hasposed a greater challenge to numerical modeling investigations thancomparable saturated zone studies, because of the heterogeneous nature ofunsaturated media as well as the great number of variables impactingunsaturated zone flow. This paper presents an integrated modelingmethodology for quantitatively characterizing percolation patterns in theunsaturated zone of Yucca Mountain, Nevada, a proposed undergroundrepository site for storing high-level radioactive waste. It takes intoaccount the multiple coupled processes of air, water, heat flow andchemical isotopic transport in Yucca Mountain s highly heterogeneous,unsaturated fractured tuffs. The modeling approach integrates a widevariety of moisture, pneumatic, thermal, and isotopic geochemical fielddata into a comprehensive three-dimensional numerical model for modelinganalyses. Modeling results are examined against different types offield-measured data and then used to evaluate different hydrogeologicalconceptual models and their results of flow patterns in the unsaturatedzone. In particular, this integration model provides a much clearerunderstanding of percolation patterns and flow behavior through theunsaturated zone, both crucial issues in assessing repositoryperformance. The integrated approach for quantifying Yucca Mountain sflow system is also demonstrated to provide a comprehensive modeling toolfor characterizing flow and transport processes in complex subsurfacesystems.

Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Pan, Lehua; Bodvarsson,Gudmundur S.

2005-03-21T23:59:59.000Z

236

Validation studies for assessing unsaturated flow and transport through fractured rock  

SciTech Connect

*The objectives of this contract are to examine hypotheses and conceptual models concerning unsaturated flow and transport through heterogeneous fractured rock and to design and execute confirmatory field and laboratory experiments to test these hypotheses and conceptual models. Important new information is presented such as the application and evaluation of procedures for estimating hydraulic, pneumatic, and solute transport coefficients for a range of thermal regimes. A field heater experiment was designed that focused on identifying the suitability of existing monitoring equipment to obtain required data. A reliable method was developed for conducting and interpreting tests for air permeability using a straddle-packer arrangement. Detailed studies of fracture flow from Queen Creek into the Magina Copper Company ore haulage tunnel have been initiated. These studies will provide data on travel time for transport of water and solute in unsaturated tuff. The collection of rainfall runoff, and infiltration data at two small watersheds at the Apache Leap Tuff Site enabled us to evaluate the quantity and rate of water infiltrating into the subsurface via either fractures or matrix. Characterization methods for hydraulic parameters relevant to Weigh-level waste transport, including fracture apertures, transmissivity, matrix porosity, and fracture wetting front propagation velocities, were developed.

Bassett, R.L.; Neuman, S.P.; Rasmussen, T.C.; Guzman, A.; Davidson, G.R.; Lohrstorfer, C.F. [Arizona Univ., Tucson, AZ (United States). Dept. of Hydrology and Water Resources

1994-08-01T23:59:59.000Z

237

Plasma Structure and Behavior of Miniature Ring-Cusp Discharges  

E-Print Network (OSTI)

UCLA NASA Space Grant - Jet Propulsion Laboratory (JPL),of electric propulsion: ion and Hall thrusters. JPL Spacepropulsion, or EP, is an attractive option for many space

Mao, Hann-Shin

2013-01-01T23:59:59.000Z

238

Notes 11. High pressure floating ring seals  

E-Print Network (OSTI)

Floating ring seals for compressors: leakage and force coefficients, seal lock up and effect on rotor stability, recommendations to reduce seal cross-coupled effects. Long oil seals as pressure barriers in industrial mixers: leakage and force coefficients, effect on rotor stability, recommendations for grooved seals with reduced leakage and lesser cross-stiffnesses.

San Andres, Luis

2009-01-01T23:59:59.000Z

239

Undulator tunability and synchrotron ring energy  

SciTech Connect

Both the photon energy of an undulator as well as its tunability are determined by the period, lambda, of the device, the magnetic gap, G (which is larger than the minimum aperture required for injection and operation of the storage ring), and the storage ring energy, E/sub R/. Given the photon energy, E/sub p/, the above parameters ultimately define the limits of operation or tunability of the undulator. In general, the larger the tunability range, the more useful the device. Therefore, for a given required maximum photon energy, it is desirable to find the operating conditions and device parameters which result in the largest tunability interval possible. This paper investigates the question of undulator tunability with emphasis on the role of the ring energy in order to find the smallest E/sub R/ consistent with the desired tunability interval and photon energy. As a guideline, we have included a preliminary criteria, concerning the tunability requirements for the Advanced Photon Source (APS) to be built at Argonne. The analysis is aimed at X-ray undulator sources on the APS but is applicable to any storage ring.

Viccaro, P.J.; Shenoy, G.K.

1987-03-01T23:59:59.000Z

240

Anticyclonic Rings in the Gulf of Mexico  

Science Conference Proceedings (OSTI)

Using the historical data set, this study describes the anticyclonic rings that separated from the Loop Current in the eastern Gulf of Mexico. Six quasi-synoptic data sets are used to describe the evolving circulation of the Gulf of Mexico from ...

Brady A. Elliott

1982-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Correction magnets for the Fermilab Recycler Ring  

SciTech Connect

In the commissioning of the Fermilab Recycler ring the need for higher order corrector magnets in the regions near beam transfers was discovered. Three types of permanent magnet skew quadrupoles, and two types of permanent magnet sextupoles were designed and built. This paper describes the need for these magnets, the design, assembly, and magnetic measurements.

James T Volk et al.

2003-05-27T23:59:59.000Z

242

Experimental results from the small isochronous ring  

DOE Green Energy (OSTI)

The Small Isochronous Ring (SIR) is a compact, low-energy storage ring designed to investigate the beam dynamics of high-intensity isochronous cyclotrons and synchrotrons at the transition energy. The ring was developed at Michigan State University (MSU) and has been operational since December 2003. It stores 20 keV hydrogen beams with a peak current of 10-20 microamps for up to 200 turns. The transverse and longitudinal profiles of extracted bunches are measured with an accuracy of approximately 1 mm. The high accuracy of the measurements makes the experimental data attractive for validation of multi-particle space charge codes. The results obtained in the ring show a fast growth of the energy spread induced by the space charge forces. The energy spread growth is accompanied by a breakup of the beam bunches into separated clusters that are involved in the vortex motion specific to the isochronous regime. The experimental results presented in the paper show a remarkable agreement with simulations performed with the code CYCO. In this paper, we discuss specifics of space charge effects in the isochronous regime, present results of experiments in SIR, and conduct a detailed comparison of the experimental data with results of simulations.

Eduard Pozdeyev

2005-05-01T23:59:59.000Z

243

Ring cavity for a Raman capillary waveguide amplifier  

DOE Patents (OSTI)

Disclosed is a regenerative ring amplifier and regenerative ring oscillator which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO[sub 2] laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplifier Stokes signal is synchronous with the mode-locked spikes of the incoming CO[sub 2] laser pump signal. 6 figs.

Kurnit, N.A.

1983-07-19T23:59:59.000Z

244

Ring cavity for a Raman capillary waveguide amplifir  

DOE Patents (OSTI)

A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

Kurnit, N.A.

1981-01-27T23:59:59.000Z

245

Ring cavity for a Raman capillary waveguide amplifier  

DOE Patents (OSTI)

A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

Kurnit, N.A.

1981-01-27T23:59:59.000Z

246

1,4-Addition of Lithium Diisopropylamide to Unsaturated Esters: Role of Rate-Limiting Deaggregation, Autocatalysis,  

E-Print Network (OSTI)

1,4-Addition of Lithium Diisopropylamide to Unsaturated Esters: Role of Rate-Limiting Deaggregation, Autocatalysis, Lithium Chloride Catalysis, and Other Mixed Aggregation Effects Yun Ma, Alexander C. Hoepker.edu Abstract: Lithium diisopropylamide (LDA) in tetrahydrofuran at -78 °C undergoes 1,4-addition

Collum, David B.

247

Explicit analytical solutions for one-dimensional steady state flow in layered, heterogeneous unsaturated soils under random  

E-Print Network (OSTI)

to the statistics of the unsaturated hydraulic conductivity and the effective water content. These first soils under random boundary conditions, Water Resour. Res., 43, W09413, doi:10.1029/2005WR004795. 1 in the literature [e.g., Warrick, 1974; Srivastava and Yeh, 1991; Tracy, 1995; Basha, 1999]. In these solutions

Lu, Zhiming

248

Comparisons of diffusive and advective fluxes of gas phase volatile organic compounds (VOCs) in unsaturated zones under natural conditions  

E-Print Network (OSTI)

is traditionally treated as the dominant mechanism of gas transport in unsaturated zones under natural conditions of the gas pressure are less than 5% [32], which is satisfied in natural attenuation. At the ground surface contri- bution of the advective flux is a more important concern in natural attenuation. According to Fig

Zhan, Hongbin

249

Graphene Layer Growth Chemistry: Five-Six-Ring Flip Reaction  

E-Print Network (OSTI)

of rate coefficients of the flip (both the addition andCHEMISTRY: FIVE-SIX-RING FLIP REACTION Russell Whitesides, 1the ring complex, or “flips” it, was identified. Competition

Whitesides, R.; Domin, D.; Salomon-Ferrer, R.; Lester Jr., W.A.; Frenklach, M.

2008-01-01T23:59:59.000Z

250

Ring Cycle for Dilating and Constricting the Nuclear Pore  

NLE Websites -- All DOE Office Websites (Extended Search)

Ring Cycle for Dilating and Constricting the Nuclear Pore Ring Cycle for Dilating and Constricting the Nuclear Pore Print Thursday, 13 June 2013 09:30 Pictured is an illustration...

251

Square-Free Rings And Their Automorphism Group  

E-Print Network (OSTI)

Finite-dimensional square-free algebras have been completely characterized by Anderson and D'Ambrosia as certain twisted semigroup algebras over a square-free semigroup S with coefficients in a field K. D'Ambrosia extended the definition of square-free to artinian rings with unity and showed every square-free ring has an associated division ring D and square-free semigroup S. We show a square-free ring can be characterized as a twisted semigroup ring over a square-free semigroup S with coefficients in a division ring D. Also, to each square-free ring there exists a short exact sequence connecting the outer automorphisms of a square-free ring to certain cohomology groups related to S and D.

Montgomery, Martin W

2008-01-01T23:59:59.000Z

252

Klystron "efficiency loop" for the ALS storage ring RF system  

E-Print Network (OSTI)

EFFICIENCY LOOP” FOR THE ALS STORAGE RING RF SYSTEM* S.at the Advanced Light Source (ALS) in order to decrease thethe cavities. 1 INTRODUCTION ALS Storage Ring RF system is

Kwiatkowski, Slawomir; Julian, Jim; Baptiste, Kenneth

2002-01-01T23:59:59.000Z

253

Study of a 'Relaxed' ALS Storage Ring Lattice  

E-Print Network (OSTI)

Proceedings Study of a 'Relaxed' ALS Storage Ring Lattice R.76SF00098. STUDY OF A 'RELAXED' ALS STORAGE RING LATTICE' R.f the Advanced Light Source (ALS) 1-1.9 GeV electron stornge

Keller, R.

2010-01-01T23:59:59.000Z

254

A Trigger Mechanism for Loop Current Ring Separations  

Science Conference Proceedings (OSTI)

The Loop Current in the Gulf of Mexico sheds large anticyclonic rings on an irregular basis. The authors attempt to show what actually triggers the ring separations. Pulses of increased transport through the Florida Straits, as observed by the ...

Wilton Sturges; Nicholas G. Hoffmann; Robert R. Leben

2010-05-01T23:59:59.000Z

255

Resonant ring for testing of accelerator RF windows  

SciTech Connect

A klystron-driven resonant ring has been designed and assembled at the Los Alamos National Laboratory for use in the Accelerator Production of Tritium Project (APT). The ring was built to test rf windows for the 700 MHz section of the APT accelerator. The ring has been designed to apply an effective power of approximately 1 MW on test windows. Details of ring design, operation and performance will be presented.

Gerken, E.; Rees, D.; Roybal, W.; Cummings, K. [Los Alamos National Lab., NM (United States); Gahl, J.M. [Univ. of New Mexico, Albuquerque, NM (United States)

1997-09-01T23:59:59.000Z

256

Gas insulated transmission line having tapered particle trapping ring  

DOE Patents (OSTI)

A gas-insulated transmission line includes an outer sheath, an inner conductor, insulating supports and an insulating gas. A particle-trapping ring is secured to each insulating support, and it is comprised of a central portion and two tapered end portions. The ends of the particle trapping ring have a smaller diameter than the central portion of the ring, so as to enable the use of the particle trapping ring in a curved transmission line.

Cookson, Alan H. (Pittsburgh, PA)

1982-01-01T23:59:59.000Z

257

Storage ring development at the National Synchrotron Light Source  

Science Conference Proceedings (OSTI)

This report contains papers on the following topics: Transverse Beam Profile Monitor; Bunch Length Measurements in the VUV Storage Ring; Photoelectric Effect Photon Beam Position Monitors; RF Receivers for Processing Electron Beam Pick-up Electrode Signals; Real-Time Global Orbit Feedback Systems; Local Orbit Feedback; Active Interlock System for High Power Insertion Devices in the X-ray Ring; Bunch Lengthening Cavity for the VUV Ring; SXLS Storage Ring Design.

Krinsky, S.; Bittner, J.; Fauchet, A.M.; Johnson, E.D.; Keane, J.; Murphy, J.; Nawrocky, R.J.; Rogers, J.; Singh, O.V.; Yu, L.H.

1991-09-01T23:59:59.000Z

258

Seasonal thermal energy storage in unsaturated soils: Model development and field validation  

DOE Green Energy (OSTI)

This report summarizes ten years of activity carried out at the Earth Sciences Division of the Lawrence Berkeley Laboratory (LBI) in the subject of seasonal storage of thermal energy in unsaturated soils. The objectives of the work were to make a conceptual study of this type of storage, to offer guidelines for planning and evaluation of the method, to produce models and simulation for an actual field experiment, to participate in an on-line data analysis of experimental results. and to evaluate the results in terms of the validation of the concept, models and the experimental techniques. The actual field experiments were performed in Beer-Sheva, Israel. Details of engineering and field operations are not included in this report.

Doughty, C.; Nir, Aharon, Tsang, Chin-Fu

1991-06-01T23:59:59.000Z

259

The influence of changes in water content on the electrical resistivity of a natural unsaturated loess  

E-Print Network (OSTI)

Non-destructive methods of measuring water content in soils have been extensively developed in the last decades, especially in soil science. Among these methods, the measurements based on the electrical resistivity are simple and reliable thanks to the clear relationship between the water content and the electrical resistivity of soils. In this work, a new electrical resistivity probe was developed to monitor the change in local water content in the triaxial apparatus. The probe is composed of two-pair of electrodes, and an electrical current is induced through the soil at the vicinity of the contact between the probe and the specimen. Some experimental data on the changes in resistivity with the degree of saturation were obtained in specimens of a natural unsaturated loess from Northern France. Two theoretical models of resistivity were also used to analyze the obtained data. Results are finally discussed with respect to the loess's water retention properties.

Munoz-Castelblanco, José; Delage, Pierre; Cui, Yu Jun

2013-01-01T23:59:59.000Z

260

Process for the generation of .alpha., .beta.-unsaturated carboxylic acids and esters using niobium catalyst  

DOE Patents (OSTI)

A process using a niobium catalyst includes the step of reacting an ester or carboxylic acid with oxygen and an alcohol in the presence a niobium catalyst to respectively produce an .alpha.,.beta.-unsaturated ester or carboxylic acid. Methanol may be used as the alcohol, and the ester or carboxylic acid may be passed over the niobium catalyst in a vapor stream containing oxygen and methanol. Alternatively, the process using a niobium catalyst may involve the step of reacting an ester and oxygen in the presence the niobium catalyst to produce an .alpha.,.beta.-unsaturated carboxylic acid. In this case the ester may be a methyl ester. In either case, niobium oxide may be used as the niobium catalyst with the niobium oxide being present on a support. The support may be an oxide selected from the group consisting of silicon oxide, aluminum oxide, titanium oxide and mixtures thereof. The catalyst may be formed by reacting niobium fluoride with the oxide serving as the support. The niobium catalyst may contain elemental niobium within the range of 1 wt % to 70 wt %, and more preferably within the range of 10 wt % to 30 wt %. The process may be operated at a temperature from 150 to 450.degree. C. and preferably from 250 to 350.degree. C. The process may be operated at a pressure from 0.1 to 15 atm. absolute and preferably from 0.5-5 atm. absolute. The flow rate of reactants may be from 10 to 10,000 L/kg.sub.(cat) /h, and preferably from 100 to 1,000 L/kg.sub.(cat) /h.

Gogate, Makarand Ratnakav (Durham, NC); Spivey, James Jerome (Cary, NC); Zoeller, Joseph Robert (Kingsport, TN)

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

MAS 305 Algebraic Structures II Notes 11 Autumn 2006  

E-Print Network (OSTI)

MAS 305 Algebraic Structures II Notes 11 Autumn 2006 Ring homomorphisms Definition Let R and S be rings, and let :R S be a function. Then is a ring homomorphism if (r1 +r2) = r1+r2 and (r1r2) = (r1)(r2) for all r1, r2 in R. A ring homomorphism which is a bijection is called an isomorphism

Bailey, R. A.

262

Mass and Lifetime Measurements in Storage Rings  

Science Conference Proceedings (OSTI)

Masses of nuclides covering a large area of the chart of nuclides can be measured in storage rings where many ions circulate at the same time. In this paper the recent progress in the analysis of Schottky mass spectrometry data is presented as well as the technical improvements leading to higher accuracy for isochronous mass measurements with a time-of-flight detector. The high sensitivity of the Schottky method down to single ions allows to measure lifetimes of nuclides by observing mother and daughter nucleus simultaneously. In this way we investigated the decay of bare and H-like 140Pr. As we could show the lifetime can be even shortened compared to those of atomic nuclei despite of a lower number of electrons available for internal conversion or electron capture.All these techniques will be implemented with further improvements at the storage rings of the new FAIR facility at GSI in the future.

Weick, H.; Beckert, K.; Beller, P.; Bosch, F.; Dimopoulou, C.; Kozhuharov, C.; Kurcewicz, J.; Mazzocco, M.; Nociforo, C.; Nolden, F.; Steck, M.; Sun, B.; Winkler, M. [Gesellschaft fuer Schwerionenforschung mbH, 64291 Darmstadt (Germany); Brandau, C.; Chen, L.; Geissel, H.; Knoebel, R.; Litvinov, S. A.; Litvinov, Yu. A.; Scheidenberger, C. [Gesellschaft fuer Schwerionenforschung mbH, 64291 Darmstadt (Germany); II. Phys. Institut, Justus-Liebig-Universitaet Giessen, 35392 Giessen (Germany)] (and others)

2007-05-22T23:59:59.000Z

263

Muon ring cooler for the MUCOOL experiment  

DOE Green Energy (OSTI)

A possibility to use a ring cooler for the MUCOOL experiment is considered. The cooler is a ring accelerator of about 37 m in circumference consisting of 8 dipole magnets, 4 short solenoids with a field flip of {+-} 2:5 T, and 4 long solenoids with adiabatic field 2-5 T. The 201.25 MHz linacs provide accelerating gradient 15 MV/min in the long straight sections. Four 1.3 m long liquid hydrogen absorbers are put between the linacs for transverse cooling, and LiH wedge absorbers in the short SS are used for the emittance exchange. To simplify the injection problem, {pi}-{mu}-production on an internal target is considered as an option for the MUCOOL experiment.

Valeri Balbekov et al.

2001-07-20T23:59:59.000Z

264

A coupled model for ring dynamics, gas flow, and oil flow through the ring grooves in IC engines  

E-Print Network (OSTI)

Oil flows through ring/groove interface play a critical role in oil transport among different regions the piston ring pack of internal combustion engines. This thesis work is intended to improve the understanding and ...

Jia, Ke, S. M. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

265

Interaction between graphene and metamaterials: split rings vs. wire pairs  

Science Conference Proceedings (OSTI)

We have recently shown that graphene is unsuitable to replace metals in the current-carrying elements of metamaterials. At the other hand, experiments have demonstrated that a layer of graphene can modify the optical response of a metal-based metamaterial. Here we study this electromagnetic interaction between metamaterials and graphene. We show that the weak optical response of graphene can be modified dramatically by coupling to the strong resonant fields in metallic structures. A crucial element determining the interaction strength is the orientation of the resonant fields. If the resonant electric field is predominantly parallel to the graphene sheet (e.g., in a complementary split-ring metamaterial), the metamaterial’s resonance can be strongly damped. If the resonant field is predominantly perpendicular to the graphene sheet (e.g., in a wire-pair metamaterial), no significant interaction exists.

Zou, Yanhong; Tassin, Philippe; Koschny, Thomas; Soukoulis, Costas

2012-05-14T23:59:59.000Z

266

Fusion of symmetric $D$-branes and Verlinde rings  

E-Print Network (OSTI)

We explain how multiplicative bundle gerbes over a compact, connected and simple Lie group $G$ lead to a certain fusion category of equivariant bundle gerbe modules given by pre-quantizable Hamiltonian $LG$-manifolds arising from Alekseev-Malkin-Meinrenken's quasi-Hamiltonian $G$-spaces. The motivation comes from string theory namely, by generalising the notion of $D$-branes in $G$ to allow subsets of $G$ that are the image of a $G$-valued moment map we can define a `fusion of $D$-branes' and a map to the Verlinde ring of the loop group of $G$ which preserves the product structure. The idea is suggested by the theorem of Freed-Hopkins-Teleman. The case where $G$ is not simply connected is studied carefully in terms of equivariant bundle gerbe modules for multiplicative bundle gerbes.

A. L. Carey; Bai-Ling Wang

2005-05-14T23:59:59.000Z

267

Structural and Vibrational Characterization of Tetracene as a ...  

Science Conference Proceedings (OSTI)

... Tetracene, an aromatic molecule consisting of 4 fused benzene rings, adopts a layered, herringbone structure in the solid state ( Figure 1 ). When a ...

268

Frostbite Theater - Liquid Nitrogen Experiments - The Flying Ring!  

NLE Websites -- All DOE Office Websites (Extended Search)

Liquid Nitrogen and the Tea Kettle Mystery! Liquid Nitrogen and the Tea Kettle Mystery! Previous Video (Liquid Nitrogen and the Tea Kettle Mystery!) Frostbite Theater Main Index Next Video (Pewter Bells) Pewter Bells The Flying Ring! A copper ring leaps off an electromagnet when it's turned on. What happens when the ring's resistance is lowered using liquid nitrogen? [ Show Transcript ] Announcer: Frostbite Theater presents... Cold Cuts! No baloney! Joanna and Steve: Just science! Joanna: Hi! I'm Joanna! Steve: And I'm Steve! Joanna: And this is an AC powered electromagnet. And this is a copper ring. When I place the copper ring on the electromagnet and turn it on, the magnet's changing magnetic field will induce an electric current in the copper ring. The current in the ring will then create it's own magnetic

269

RING ROAD SOUTH IVERSITY ROAD WEST  

E-Print Network (OSTI)

Webb ­ Earth Sciences R5 Aston Webb ­ B Block R6 Aston Webb ­ Great Hall R7 Aston Webb ­ C Block R8P P P Barber Institute ELSROAD M R.15 R.30 24h Security R.3 RING ROAD SOUTH U N IVERSITY ROAD WEST South Car Park P R21 R17 R18 R22 Main Library R19 R20R20 R23 R24R24 R25 Munrow Sport Centre R27 R26 R28

Sloman, Aaron

270

RING ROAD SOUTH IVERSITY ROAD WEST  

E-Print Network (OSTI)

­ Earth Sciences R5 Aston Webb ­ B Block R6 Aston Webb ­ Great Hall R7 Aston Webb ­ C Block R8 PhysicsP P P Barber Institute ELSROAD M R.15 R.30 24h Security R.3 RING ROAD SOUTH U N IVERSITY ROAD WEST South Car Park P R21 R17 R18 R22 Main Library R19 R2020 R23 R2424 R25 Munrow Sport Centre R27 R26 R28 R

Yao, Xin

271

The hydroxyl radical initiated oxidation of unsaturated hydrocarbons in the troposphere: a theoretical and experimental approach  

E-Print Network (OSTI)

Isoprene is the dominant non-methane organic compound emitted by vegetation into the atmosphere, with a global emission rate of ~ 500 Tg yr-1. Its oxidation serves as a major source of ground level ozone in North America during the summer months. Despite the significant impact on tropospheric chemistry, questions remain concerning the detailed oxidation mechanism. The initial step in the mechanism is the addition of OH to form four distinct isomers. The relative branching between these isomers influences the distribution of the final products. I present a comprehensive investigation into the mechanistic details of early steps in the oxidation mechanism of unsaturated hydrocarbons in the troposphere and employ theoretical and experimental techniques. To understand the detailed kinetics of the initial OH addition to unsaturated hydrocarbons, I first present a model developed for the ethylene-OH system. I present the details of a robust two-transition state model. I extend the developed two-transition state model to the case of OH addition to isoprene. Excellent agreement with observed temperature and pressure dependent rate constants affords a high confidence level in understanding of the kinetics and in the calculated branching ratio of the initial OH addition step. I then focus attention on the subsequent reactivity of the OH-isoprene adducts. Until recently, all four of the OH-isoprene adducts were supposed to have reacted with O2 via addition to form alkylperoxy radicals. Previous computational results suggest that two of the OH-isoprene adducts undergo an intramolecular cyclic isomerization followed by hydrogen abstraction by O2 to form stable carbonyl compounds. I have synthesized photolytic precursors, presenting a novel approach to probe the subsequent reactivity of individual hydroxyalkyl radicals. Initial verification of the cyclic isomerization pathway involved synthesis of the photolytic precursor corresponding to the 1,3-butadiene-OH adduct. A culmination of theoretical and experimental techniques allowed verification of the cyclic isomerization pathway. I synthesized the photolytic precursor, which provided a single isoprene-OH adduct. Employing laser photolysis/laser induced fluorescence, time-dependent multiplexed mass spectrometry, velocity map ion imaging, and theoretical techniques, we present the full characterization of the reactivity of the single isoprene-OH adduct in the presence of O2.

Tullos, Erin Elizabeth

2007-05-01T23:59:59.000Z

272

Reaction progress pathways for glass and spent fuel under unsaturated conditions  

Science Conference Proceedings (OSTI)

The source term for the release of radionuclides from a nuclear waste repository is the waste form. In order to assess the performance of the repository and the engineered barrier system (EBS) compared to regulations established by the Nuclear Regulatory Commission and the Environmental Protection Agency it is necessary (1) to use available data to place bounding limits on release rates from the EBS, and (2) to develop a mechanistic predictive model of the radionuclide release and validate the model against tests done under a variety of different potential reaction conditions. The problem with (1) is that there is little experience to use when evaluating waste form reaction under unsaturated conditions such that errors in applying expert judgment to the problem may be significant. The second approach, to test and model the waste form reaction, is a more defensible means of providing input to the prediction of radionuclide release. In this approach, information related to the source term has a technical basis and provides a starting point to make reasonable assumptions for long-term behavior. Key aspects of this approach are an understanding of the reaction progress mechanism and the ability to model the tests using a geochemical code such as EQ3/6. Current knowledge of glass, UO{sub 2}, and spent fuel reactions under different conditions are described below.

Bates, J.; Finn, P.; Bourcier, W.; Stout, R.

1994-10-01T23:59:59.000Z

273

Modeling of Unsaturated Salt-cake Dissolution for S-109 Simulant  

Science Conference Proceedings (OSTI)

The Environmental Simulation Program (V7.0, OLI Systems, Inc.) with V7DBLSLT, the latest version of the double salt database developed by the Institute of Clean Energy Technology (ICET), was used to predict effluent stream compositions and densities, residual salt-cake composition, and salt-cake heights for an unsaturated salt-cake dissolution test with a simulant representative of waste contained in Hanford tank 241-S-109. Predictions for major cation and anion concentrations were in excellent agreement with the experimental data obtained at the Applied Research Center (ARC) at Florida International University (FIU). The utility of ESP as a means to predict effluent stream compositions and effluent stream properties, such as density and column salt-cake height, is demonstrated through the agreement between experimental and predicted values. These, and previous calculations, validate the use of thermodynamic models (with proper chemistry representations) for HLW pretreatment and retrievals. A powerful and useful tool is the result. Cost reductions are possible as the amount of sampling and subsequent laboratory analysis can be reduced. Additionally, overall processing risk is reduced through the ability to rapidly evaluate different processing and retrieval scenarios. The application of appropriate models can thus lead to more efficient operations and campaign cost savings while also evaluating parameters pertinent to safety. (authors)

Toghiani, R.K.; Lindner, J.S. [Institute for Clean Energy Technology, Mississippi State Univ., Starkville, MS (United States); Toghiani, R.K. [Dave C. Swalm School of Chemical Engineering, Mississippi State Univ., Starkville, MS (United States)

2008-07-01T23:59:59.000Z

274

Circumference Correction Chicanes for Damping Rings P. Emma, T. Raubenheimer  

NLE Websites -- All DOE Office Websites (Extended Search)

Circumference Correction Chicanes for Circumference Correction Chicanes for Damping Rings P. Emma, T. Raubenheimer August 14,1998 1 Introduction Several large low-emittance damping rings are presently being designed to meet the requirements of future linear colliders. These rings tend to have relatively large circumferences ∼300 m so that they can damp many trains of bunches at the same time. With the large circumference, the path length around the ring may become quite sensitive to thermal and ground motion effects. In addition, most of the rings include damping wigglers whose path length varies with their strength. In e-/e+ storage rings, the beam revolution time is determined by the rf frequency. Thus, a change in the nominal path length will cause a change in both the beam energy and the

275

Design Considerations for High Energy Electron -- Positron Storage Rings  

DOE R&D Accomplishments (OSTI)

High energy electron-positron storage rings give a way of making a new attack on the most important problems of elementary particle physics. All of us who have worked in the storage ring field designing, building, or using storage rings know this. The importance of that part of storage ring work concerning tests of quantum electrodynamics and mu meson physics is also generally appreciated by the larger physics community. However, I do not think that most of the physicists working tin the elementary particle physics field realize the importance of the contribution that storage ring experiments can make to our understanding of the strongly interacting particles. I would therefore like to spend the next few minutes discussing the sort of things that one can do with storage rings in the strongly interacting particle field.

Richter, B.

1966-11-00T23:59:59.000Z

276

Construction of MDS self-dual codes over Galois rings  

Science Conference Proceedings (OSTI)

The purpose of this paper is to construct nontrivial MDS self-dual codes over Galois rings. We consider a building-up construction of self-dual codes over Galois rings as a GF(q)-analogue of (Kim and Lee, J Combin Theory ser A, 105:79---95). We ... Keywords: 13H99, 94B05, Galois ring, MDS code, Self-dual code

Jon-Lark Kim; Yoonjin Lee

2007-11-01T23:59:59.000Z

277

First Constraints on Rings in the Pluto System  

E-Print Network (OSTI)

Simple theoretical calculations have suggested that small body impacts onto Pluto's newly discovered small satellites, Nix and Hydra, are capable of generating time-variable rings or dust sheets in the Pluto system. Using HST/ACS data obtained on 2006 February 15 and 2006 March 2, we find no observational evidence for such a ring system and present the first constraints on the present-day I/F and optical depth of a putative ring system. At the 1500-km radial resolution of our search, we place a 3-sigma upper limit on the azimuthally-averaged normal I/F of ring particles of 5.1x10^-7 at a distance of 42,000 km from the Pluto-Charon barycenter, the minimum distance for a dynamically stable ring (Stern et al., 1994; Nagy et al., 2006); 4.4x10^-7 at the orbit of Nix; and 2.5x10^-7 at the orbit of Hydra. For an assumed ring particle albedo of 0.04 (0.38), these I/F limits translate into 3-sigma upper limits on the normal optical depth of macroscopic ring particles of 1.3x10^-5 (1.4x10^-6), 1.1x10^-5 (1.2x10^-6), 6.4x10^-6 (6.7x10^-7), respectively. Were the New Horizons spacecraft to fly through a ring system with optical depth of 1.3x10^-5, it would collide with a significant number of potentially damaging ring particles. We therefore recommend that unless tighter constraints can be obtained, New Horizons cross the putative ring plane within 42,000 km of the Pluto-Charon barycenter, where rings are dynamically unstable. We derive a crude estimate of the lifetime of putative ring paritcles of 900 years.

A. J. Steffl; S. A. Stern

2006-08-01T23:59:59.000Z

278

Interference of a thermal Tonks gas on a ring  

E-Print Network (OSTI)

A nonzero temperature generalization of the Fermi-Bose mapping theorem is used to study the exact quantum statistical dynamics of a one-dimensional gas of impenetrable bosons on a ring. We investigate the interference produced when an initially trapped gas localized on one side of the ring is released, split via an optical-dipole grating, and recombined on the other side of the ring. Nonzero temperature is shown not to be a limitation to obtaining high visibility fringes.

Kunal K. Das; M. D. Girardeau; E. M. Wright

2002-05-28T23:59:59.000Z

279

Measuring Gravito-magnetic Effects by Multi Ring-Laser Gyroscope  

E-Print Network (OSTI)

We propose an under-ground experiment to detect the general relativistic effects due to the curvature of space-time around the Earth (de Sitter effect) and to rotation of the planet (dragging of the inertial frames or Lense-Thirring effect). It is based on the comparison between the IERS value of the Earth rotation vector and corresponding measurements obtained by a tri-axial laser detector of rotation. The proposed detector consists of six large ring-lasers arranged along three orthogonal axes. In about two years of data taking, the 1% sensitivity required for the measurement of the Lense-Thirring drag can be reached with square rings of 6 $m$ side, assuming a shot noise limited sensitivity ($ 20 prad/s/\\sqrt{Hz}$). The multi-gyros system, composed of rings whose planes are perpendicular to one or the other of three orthogonal axes, can be built in several ways. Here, we consider cubic and octahedron structures. The symmetries of the proposed configurations provide mathematical relations that can be used to study the stability of the scale factors, the relative orientations or the ring-laser planes, very important to get rid of systematics in long-term measurements, which are required in order to determine the relativistic effects.

F. Bosi; G. Cella; A. Di Virgilio; A. Ortolan; A. Porzio; S. Solimeno; M. Cerdonio; J. P. Zendri; M. Allegrini; J. Belfi; N. Beverini; B. Bouhadef; l G. Carelli; I. Ferrante; E. Maccioni; R. Passaquieti; F. Stefani; M. L. Ruggiero; A. Tartaglia; K. U. Schreiber; A. Gebauer; J-P. R. Wells

2011-06-24T23:59:59.000Z

280

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality  

NLE Websites -- All DOE Office Websites (Extended Search)

Rotary Firing in Ring-Shaped Protein Explains Unidirectionality Print Hexameric motor proteins represent a complex class of molecular machines that variously push and pull on...

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

metallurgical evaluation of spray deposited and ring rolled in718  

Science Conference Proceedings (OSTI)

metallurgy for the more compositionally complex superalloys for gas turbine applications [1-5]. ... of IN 718 as in specification, VIM heat and in spray ring.

282

Mechanical support of a ceramic gas turbine vane ring - Energy ...  

Wind Energy; Partners (27) Visual Patent Search; Success Stories; News; Events; Mechanical support of a ceramic gas turbine vane ring United States ...

283

A Performance Modeling and Evaluation of the Cambridge Fast Ring  

Science Conference Proceedings (OSTI)

Performance of the Cambridge Fast Ring (CFR), a high-speed slotted ring with normal slots, is studied. It is shown that the CFR can be represented by a multiqueue multiple cyclic server model with a 1-limited service discipline and with a restriction ... Keywords: 1-limited service discipline, Cambridge Fast Ring, approximate analytic M/G/1 vacation model, exact necessary and sufficient stability conditions, high-speed slotted ring, local area networks, message waiting times, multiqueue multiple cyclic server model, normal slots, performance evaluation, performance modeling, queueing theory., vacation period

Mirjana Zafirovic-Vukotic; Ignas G. Niemegeers

1992-09-01T23:59:59.000Z

284

Accumulator Ring Commissioning Latest Step for Spallation Neutron...  

NLE Websites -- All DOE Office Websites (Extended Search)

Accumulator Ring Commissioning Latest Step for Spallation Neutron Source BNL SNS Homepage The following is from a press release issued by Oak Ridge National Laboratory. OAK RIDGE,...

285

A Shallow Attenuating Anomaly Inside The Ring Fracture Of The...  

Open Energy Info (EERE)

Shallow Attenuating Anomaly Inside The Ring Fracture Of The Valles Caldera, New Mexico Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Shallow...

286

Introductory statistical mechanics for electron storage rings  

Science Conference Proceedings (OSTI)

These lectures introduce the beam dynamics of electron-positron storage rings with particular emphasis on the effects due to synchrotron radiation. They differ from most other introductions in their systematic use of the physical principles and mathematical techniques of the non-equilibrium statistical mechanics of fluctuating dynamical systems. A self-contained exposition of the necessary topics from this field is included. Throughout the development, a Hamiltonian description of the effects of the externally applied fields is maintained in order to preserve the links with other lectures on beam dynamics and to show clearly the extent to which electron dynamics in non-Hamiltonian. The statistical mechanical framework is extended to a discussion of the conceptual foundations of the treatment of collective effects through the Vlasov equation.

Jowett, J.M.

1986-07-01T23:59:59.000Z

287

Design and simulation of fast pulsed kicker/bumper units for the positron accumulator ring at APS  

Science Conference Proceedings (OSTI)

In the design of fast pulsed kicker/bumper units for a positron accumulator ring (PAR) at APS, different pulse forming networks (PFN) are considered and different structures for the magnet are studied and simulated. This paper describes some design considerations and computer simulation results of different designs. 4 refs., 6 figs.

Wang, J.; Volk, G.J.

1991-01-01T23:59:59.000Z

288

MAXIMAL ANALYTIC EXTENSIONS OF THE EMPARAN-REALL BLACK RING  

E-Print Network (OSTI)

MAXIMAL ANALYTIC EXTENSIONS OF THE EMPARAN-REALL BLACK RING Piotr T. Chru´sciel & Julien Cortier Abstract We construct a Kruskal-Szekeres-type analytic extension of the Emparan- Reall black ring-Reall [13] metrics form a remarkable class of vacuum black hole solutions of Einstein equations in dimension

Paris-Sud XI, Université de

289

Wavelength routing of uniform instances in all-optical rings  

Science Conference Proceedings (OSTI)

We consider the problem of routing uniform communication instances in switched optical rings that use wavelength-division multiplexing technology. A communication instance is called uniform if it consists exactly of all pairs of nodes in the graph whose ... Keywords: Edge load, Optical ring, Routing, Uniform instance, WDM, Wavelength index

Lata Narayanan; Jaroslav Opatrny

2005-12-01T23:59:59.000Z

290

The Origin of an Anomalous Ring in the Southeast Atlantic  

Science Conference Proceedings (OSTI)

A warm core ring in the southeast Atlantic, previously thought to have come from the Brazil–Falklands (Malvinas) confluence, is traced back to the Agulhas retroflection. The path of this ring, sampled at 36°S, 4°E on 23 January 1993 during the ...

Elaine L. McDonagh; Karen J. Heywood

1999-08-01T23:59:59.000Z

291

Density inhomogeneity driven electrostatic shock waves in planetary rings  

SciTech Connect

Dust inertia and background density driven dust drift shock waves are theoretically studied in a rotating planetary environment and are subsequently applied to the planetary rings where the collisional effects are pronounced. It has been found that the system under consideration admits significant shock formation if the collision frequency is of the order of or less than the rotational frequency of the Saturn's rings.

Masood, W.; Siddiq, M. [Theoretical Plasma Physics Division (TPPD), PINSTECH, P. O. Nilore, Islamabad 44000 (Pakistan); National Center for Physics (NCP), Islamabad 44000 (Pakistan); Rizvi, H.; Haque, Q. [Theoretical Plasma Physics Division (TPPD), PINSTECH, P. O. Nilore, Islamabad 44000 (Pakistan); Hasnain, H. [NILOP, P. O. Nilore, Islamabad 44000 (Pakistan); PIEAS, P. O. Nilore, Islamabad 44000 (Pakistan)

2011-05-15T23:59:59.000Z

292

Master Thesis Ring Imaging Cerenkov Counter with Aerogel  

E-Print Network (OSTI)

[a4]report #12; i Master Thesis Ring Imaging Cerenkov Counter with Aerogel Radiator for HERMES-inlusive spin asymmetries. In the past, HERMES used a threshold Cerenkov counter as one of its four particle the threshold Cerenkov counter with a Ring Imaging Cerenkov system(RICH) in 1998, so that it can separate #25

293

A High Density Polarized Hydrogen Gas Target for Storage Rings  

E-Print Network (OSTI)

in a storage ring to study the target characteristics (nuclear polarization, target thickness, radiation 10 13 ~ H/cm 2 . The target polarization was unaffected by prolonged exposure of the target to beams in the use of polarized gases as internal targets in particle storage rings 1 . The first application

294

Mobile Search for a Black Hole in an Anonymous Ring  

Science Conference Proceedings (OSTI)

We address the problem of mobile agents searching a ring network for a highly harmful item, a black hole, a stationary process destroying visiting agents upon their arrival. No observable trace of such a destruction will be evident. The location of the ... Keywords: distributed computing, hazardous search, mobile agents, ring network

Stefan Dobrev; Paola Flocchini; Giuseppe Prencipe; Nicola Santoro

2001-10-01T23:59:59.000Z

295

Loop Current excursions and ring detachments during 1993–2009  

Science Conference Proceedings (OSTI)

Linkages between the variability of Loop Current LC surface dynamics, LC ring detachments, and the mean sea height anomaly in the Gulf of Mexico GOM are explored using a new methodology that locates the LC fronts and detects the shedding of LC rings. ...

David Lindo-Atichati, Francis Bringas, Gustavo Goni

2013-07-01T23:59:59.000Z

296

Room Temperature Aging Study of Butyl O-rings  

Science Conference Proceedings (OSTI)

During testing under the Enhanced Surveillance Campaign in 2001, preliminary data detected a previously unknown and potentially serious concern with recently procured butyl o-rings. All butyl o-rings molded from a proprietary formulation throughout the period circa 1999 through 2001 had less than a full cure. Tests showed that sealing force values for these suspect o-rings were much lower than expected and their physical properties were very sensitive to further post curing at elevated temperatures. Further testing confirmed that these o-rings were approximately 50% cured versus the typical industry standard of > 90% cured. Despite this condition, all suspect o-rings fully conformed to their QC acceptance requirements, including their individual product drawing requirements.

Mark Wilson

2009-08-07T23:59:59.000Z

297

New ring-linear codes from dualization in projective Hjelmslev geometries  

Science Conference Proceedings (OSTI)

In this article, several new constructions for ring-linear codes are given. The class of base rings are the Galois rings of characteristic 4, which include Keywords: 05B25, 51C05, 51E20, 94B05, 94B27, Galois ring, Gray map, Hjelmslev geometry, Homogeneous weight, Kerdock code, Lee weight, Ring-linear code

Michael Kiermaier; Johannes Zwanzger

2013-01-01T23:59:59.000Z

298

Ring1B Contains a Ubiquitin-Like Docking Module for Interaction with Cbx Proteins  

Science Conference Proceedings (OSTI)

Polycomb group (PcG) proteins are a special set of repressive transcription factors involved in epigenetic modifications of chromatin. They form two functionally distinct groups of catalytically active complexes: Polycomb repressive complex 1 (PRC1) and 2 (PRC2). The PRC1 complex is an important yet poorly characterized multiprotein histone ubiquitylation machine responsible for maintaining transcriptionally silent states of genes through histone H2A K119 modification. The Ring domain containing subunits of PRC1 also have substrate-targeting domains that interact with Cbx proteins, which have been implicated in chromatin and RNA binding. In this work, we present a high resolution structure of the C-terminal domain of Ring1B, revealing a variant ubiquitin-like fold with a distinct conserved surface region. On the basis of crystal structure and mutational analysis of this domain we show that the conserved surface is responsible for interaction with Cbx members of the PRC1 and homodimer formation. These data suggest a mechanism by which Ring1B serves as an adaptor that mediates binding between the members of the PRC1 complex and the nucleosome.

Bezsonova, Irina; Walker, John R.; Bacik, John P.; Duan, Shili; Dhe-Paganon, Sirano; Arrowsmith, Cheryl H.; (Toronto)

2010-04-19T23:59:59.000Z

299

Development of Ring Imaging Cherenkov Detectors for LHCb  

E-Print Network (OSTI)

The work described in this thesis has been carried out in the framework of the development program of the Ring Imaging Cherenkov (RICH) detectors of the LHCb experiment. LHCb will operate at the Large Hadron Collider at CERN, and it will perform a wide range of measurements in the b-hadrons realm. The extensive study of CP violation and rare decays in the b-hadron system are the main goals of the experiment. An introduction to CP violation in hadronic interactions is given in chapter 1. The high b-b bar production cross section at the LHC energy will provide an unprecedented amount of data which will give LHCb a unique opportunity for precision tests on a large set of physics channels as well as a promising discovery potential for sources of CP violation arising from physics beyond the Standard Model. The experiment is designed in such a way to optimally match the kinematic structure of events where a pair of b quarks is produced in the collision between to 7 GeV protons. Chapter 2 is devoted to an overview o...

Bellunato, T; Matteuzzi, C

2003-01-01T23:59:59.000Z

300

Ring Current Influence on Auroral Electrojet Predictions  

E-Print Network (OSTI)

. Geomagnetic storms and substorms develop under strong control of the solar wind. This is demonstrated by the fact that the geomagnetic activity indices Dst and AE can be predicted from the solar wind alone. A consequence of the strong control by a common source is that substorm and storm indices tend to be highly correlated. However, a part of this correlation is likely to be an eect of internal magnetospheric processes, such as a ring-current modulation of the solar wind-AE relation. The present work extends previous studies of nonlinear AE predictions from the solar wind. It is examined whether the AE predictions are modulated by the Dst index.This is accomplished by comparing neural network predictions from Dst and the solar wind, with predictions from the solar wind alone. Two conclusions are reached: (1) with an optimal set of solar-wind data available, the AE predictions are not markedly improved by the Dst input, but (2) the AE predictions are improved by Dst if less than, o...

H. Gleisner; H. Lundstedt

1999-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

First Constraints on Rings in the Pluto System  

E-Print Network (OSTI)

Simple theoretical calculations have suggested that small body impacts onto Pluto's newly discovered small satellites, Nix and Hydra, are capable of generating time-variable rings or dust sheets in the Pluto system. We present the first observational constraints on the present-day optical depth of such debris systems using HST/ACS data obtained on 2006 February 15 and 2006 March 2. We find that any Plutonian dust rings between Nix and Hydra must have optical depths of 2x10^(-5) or lower, when averaged over 1000-km radial distance scales. While usefully constraining, the derived ring optical depth limits are still a factor of four higher than those predicted by Stern et al. (2006). Were the New Horizons spacecraft to fly through a ring system with optical depth as high as 2x10^(-5), it would collide with a significant number of potentially damaging ring particles. We therefore recommend that New Horizons cross the potential ring plane at a radial distance where dust rings are not expected due to either dynamic...

Steffl, A J

2006-01-01T23:59:59.000Z

302

Combination ring cavity and backward Raman waveguide amplifier  

DOE Patents (OSTI)

A combination regenerative ring and backward Raman waveguide amplifier and a combination regenerative ring oscillator and backward Raman waveguide amplifier which produce Raman amplification, pulse compression, and efficient energy extraction from the CO/sub 2/ laser pump signal for conversion into a Stokes radiation signal. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman waveguide amplifier. The backward Raman waveguide amplifier configuration extracts a major portion of the remaining energy from the CO/sub 2/ laser pump signal for conversion to Stokes radiation.

Kurnit, N.A.

1981-03-13T23:59:59.000Z

303

Beam Loss Monitors for NSLS-II Storage Ring  

Science Conference Proceedings (OSTI)

The shielding for the NSLS-II storage ring will provide adequate protection for the full injected beam losses in two cells of the ring around the injection point, but the remainder of the ring is shielded for lower losses of Cerenkov light as electrons transit ultra-pure fused silica rods placed close to the inner edge of the VC. The entire length of the rod will collect light from the electrons of the spread out shower resulting from the small glancing angle of the lost beam particles to the VC wall. The design and measurements results of the prototype Cerenkov BLM will be presented.

Kramer, S.L.; Cameron, P.

2011-03-28T23:59:59.000Z

304

Black Rings, Boosted Strings and Gregory-Laflamme  

E-Print Network (OSTI)

We investigate the Gregory-Laflamme instability for black strings carrying KK-momentum along the internal direction. We demonstrate a simple kinematical relation between the thresholds of the classical instability for the boosted and static black strings. We also find that Sorkin's critical dimension depends on the internal velocity and in fact disappears for sufficiently large boosts. Our analysis implies the existence of an analogous instability for the five-dimensional black ring of Emparan and Reall. We also use our results for boosted black strings to construct a simple model of the black ring and argue that such rings exist in any number of space-time dimensions.

J. L. Hovdebo; R. C. Myers

2006-01-12T23:59:59.000Z

305

Positron Accumulator Ring (PAR) power supply  

SciTech Connect

The Positron Accumulator Ring (PAR) consists of 8 dipole magnets connected in series. These magnets are energized via one 12-pulse dc power supply. The power supply consists of four phase controlled half-wave wye group converters. Each of the two half-wave converters are connected through an interphase transformer to obtain a full-wave converter with 120{degrees} conduction. The input voltage for these two half-wave converters are 180{degrees} apart. The two full-wave converters are connected in parallel through a third interphase transformer. This type of connection of the converters not only provides the required output current, it also improves the input power factor of the power supply. The output of the wye group converters is filtered through a passive L-R-C filter to reduce the ripple content of the output current. At low current values of the power supply the current ripple is high, thus a large filter is needed, which adds to the cost of the power supply, however at high output current levels, the current ripple is less severe. The large size of the filter can be reduced by adding an anti-parallel rectifier diode(D1) to the output of the power supply. A freewheeling diode(D2) is connected before the choke to circulate the current once the power supply is turned off. In order to measure the current in the magnet a high precision, low drift, zero flux current transductor is used. This transductor senses the magnet current which provides a feedback signal to control the gating of the converter`s thyristors. A true 14 bit Digital to Analog Converter (DAC) is programmed by the control computer for the required current value, providing a reference for the current regulator. Fast correction of the line transients is provided by a relatively fast voltage loop controlled by a high gain slow response current loop.

Fathizadeh, M.

1995-08-01T23:59:59.000Z

306

A Measurement System for Systematic Hydrological Characterization of Unsaturated Fractured Welded Tuff in a Mined Underground Tunnel  

SciTech Connect

A field investigation of unsaturated flow through a lithophysal unit of fractured welded tuff containing lithophysal cavities has been initiated. To characterize flow in this spatially heterogeneous medium, a systematic approach has been developed to perform tests in boreholes drilled at regular intervals in an underground tunnel (drift). In this paper, we describe the test equipment system that has been built for this purpose. Since the field-scale measurements, of liquid flow in the unsaturated, fractured rocks, require continuous testing for periods of days to weeks, the control of test equipment has been fully automated, allowing operation with no human presence at the field site. Preliminary results from the first set of tests are described. These tests give insight into the role of the matrix (perhaps also lithophysal cavities) as potential storage during the initial transient flow prior to the breakthrough of water at the drift crown, as well as the role of connected fractures that provide the subsequent quasi-steady flow. These tests also reveal the impact of evaporation on seepage into the drift.

R. J. Cook; R. Salve; B.M. Freifeld; Y.W. Tsang

2001-11-21T23:59:59.000Z

307

Timing and RF Synchrotronization for Filling PEP/SPEAR with the SLC Damping Rings  

E-Print Network (OSTI)

e- bunches from the SLC Damping Rings (VRF = 714 MHz) intothe storage rings PEP (VRF = 353MHz) and SPEAR (VRF = 358 MHz). The required relalive

Ronan, M.T.

2011-01-01T23:59:59.000Z

308

[Characterization of historical infiltration in the unsaturated zone at the Nevada Test Site using chloride, bromide, and chlorine-36 as environmental tracers]; [Final subcontract report  

SciTech Connect

This document is an end-of-contract report, prepared by Hydro Geo Chem for Los Alamos National Laboratory under contract number 9-XDD-6329F-1. The ultimate goal of this work is to characterize historical infiltration and unsaturated flow in the Yucca Mountain area of the Nevada Test Site. Work on this contract has focused on using chloride, bromide, stable chlorine isotopes, and chlorine-36 distributions to evaluate the depth of infiltration in the unsaturated zone. Effort in support of this work has included developing analytical procedures, exploring ways in which to separate the. meteoric component from the rock component, and meeting quality assurance requirements.

NONE

1991-05-17T23:59:59.000Z

309

Ring Cycle for Dilating and Constricting the Nuclear Pore  

NLE Websites -- All DOE Office Websites (Extended Search)

Ring Cycle for Dilating and Ring Cycle for Dilating and Constricting the Nuclear Pore Ring Cycle for Dilating and Constricting the Nuclear Pore Print Thursday, 13 June 2013 09:30 Pictured is an illustration of several nuclear pore complexes (NPCs) embedded in a cell nucleus. NPCs act as gatekeepers between a cell's cytoplasm and its nucleus. Based on crystallographic analyses, Sozanne R. Solmaz et al. uncover the molecular mechanism that underlies the large changes in diameter of NPCs and suggest a "ring cycle" mechanism for dilating and constricting the central NPC channel. The model could explain the ability of NPCs to accommodate transport substrates of a large size range and rapidly adjust to cellular transport needs. Read the full article. (Image courtesy of Sozanne R. Solmaz, Günter Blobel, and Ivo Melčák.)

310

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress  

NLE Websites -- All DOE Office Websites (Extended Search)

Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported...

311

SPH Simulations of Accretion Disks and Narrow Rings  

E-Print Network (OSTI)

We model a massless viscous disk using Smoothed Particle Hydrodynamics (SPH) and note that it evolves according to the Lynden-Bell \\& Pringle theory (1974) until a non-axisymmetric instability develops at the inner edge of the disk. This instability may have the same origin as the instability of initially axisymmetric viscous disks discussed by Lyubarskij et al. (1994). To clarify the evolution we evolved single and double rings of particles. It is actually inconsistent with the SPH scheme to set up a single ring as an initial condition because SPH assumes a smoothed initial state. As would be expected from an SPH simulation, the ring rapidly breaks up into a band. We analyse the stability of the ring and show that the predictions are confirmed by the simulation.

Sarah T. Maddison; James R. Murray; Joe J. Monaghan

1995-07-12T23:59:59.000Z

312

Graphene Layer Growth Chemistry: Five-Six-Ring Flip Reaction  

E-Print Network (OSTI)

CHEMISTRY: FIVE-SIX-RING FLIP REACTION R. Whitesides, 1 D.reverse its orientation, or “flips,” after activation by aRate constants for the flip reaction were obtained by the

Whitesides, Russell; Domin, Dominik; Lester Jr., William A.; Frenklach, Michael

2007-01-01T23:59:59.000Z

313

spray forming and post processing of superalloy rings  

Science Conference Proceedings (OSTI)

The production of spray formed superalloy rings made of IN718 and U720 for aero engine components in order to reduce production cost is the goal of the ...

314

Optimization Online - The Price of Atomic Selfish Ring Routing  

E-Print Network (OSTI)

May 27, 2008 ... The Price of Atomic Selfish Ring Routing. Bo Chen (b.chen ***at*** warwick.ac.uk ) Xujin Chen (xchen ***at*** amss.ac.cn) Xiaodong Hu (xdhu ...

315

Mobile Search for a Black Hole in an Anonymous Ring  

E-Print Network (OSTI)

as complexity questions. We first consider agents that start from the same homebase (co-located). We prove then consider the case of agents that start from different homebases (dispersed) and we show that, if the ring

Flocchini, Paola

316

The KACST Heavy?Ion Electrostatic Storage Ring  

Science Conference Proceedings (OSTI)

A novel Electrostatic Storage Ring (ESR) for beams at energies up to 30keV/q is now being constructed at the National Centre for Mathematics and Physics (NCMP)

A. A. Almuqhim; S. M. Alshammari; M. O. A. El Ghazaly; A. I. Papash; C. P. Welsch

2011-01-01T23:59:59.000Z

317

Life Cycles of Hurricane-Like Vorticity Rings  

Science Conference Proceedings (OSTI)

The asymmetric dynamics of potential vorticity mixing in the hurricane inner core are further advanced by examining the end states that result from the unforced evolution of hurricane-like vorticity rings in a nondivergent barotropic model. The ...

Eric A. Hendricks; Wayne H. Schubert; Richard K. Taft; Huiqun Wang; James P. Kossin

2009-03-01T23:59:59.000Z

318

3D-Simulation Studies of SNS Ring Doublet Magnets  

E-Print Network (OSTI)

3D-SIMULATION STUDIES OF SNS RING DOUBLET MAGNETS* J.G. Wang # , SNS/ORNL, Oak Ridge, TN 37831-6471, U.S.A. N.the Spallation Neutron Source (SNS) at ORNL employs in its

Wang, J.G.; Tsoupas N.; Venturini, M.

2005-01-01T23:59:59.000Z

319

Hom dampers for ALS storage ring RF cavities  

E-Print Network (OSTI)

of the HOM dampers on ALS rf cavities was an immediatesuccess. Now, the ALS storage ring can operate with the 312The cross-section of the ALS third harmonic cavity with two

2003-01-01T23:59:59.000Z

320

Generic Linear Algebra and Quotient Rings in Maple - CECM  

E-Print Network (OSTI)

fields in Maple, we have designed a simple to use facility that permits the. Maple user to define a field, Euclidean domain, integral domain or ring so that our ...

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Graphene Layer Growth Chemistry: Five-Six-Ring Flip Reaction  

E-Print Network (OSTI)

are incorporated into growing graphene layers and hence willGRAPHENE LAYER GROWTH CHEMISTRY: FIVE-SIX-RING FLIP REACTIONon the zigzag edge of a graphene layer. A new reaction

Whitesides, R.; Domin, D.; Salomon-Ferrer, R.; Lester Jr., W.A.; Frenklach, M.

2008-01-01T23:59:59.000Z

322

Phase fluctuations in anisotropic Bose condensates: from cigars to rings  

E-Print Network (OSTI)

We study the phase-fluctuating condensate regime of ultra-cold atoms trapped in a ring-shaped trap geometry, which has been realized in recent experiments. We first consider a simplified box geometry, in which we identify the conditions to create a state that is dominated by thermal phase-fluctuations, and then explore the experimental ring geometry. In both cases we demonstrate that the requirement for strong phase fluctuations can be expressed in terms of the total number of atoms and the geometric length scales of the trap only. For the ring-shaped trap we discuss the zero temperature limit in which a condensate is realized where the phase is fluctuating due to interactions and quantum fluctuations. We also address possible ways of detecting the phase fluctuating regime in ring condensates.

L. Mathey; A. Ramanathan; K. C. Wright; S. R. Muniz; W. D. Phillips; Charles W. Clark

2010-07-02T23:59:59.000Z

323

Linear lattice modeling of the recycler ring at Fermilab  

SciTech Connect

Substantial differences are found in tunes and beta functions between the existing linear model and the real storage ring. They result in difficulties when tuning the machine to new lattice conditions. We are trying to correct the errors by matching the model into the real machine using Orbit Response Matrix (ORM) Fit method. The challenges with ORM particularly in the Recycler ring and the results are presented in this paper.

Xiao, Meiqin; Valishev, Alexander; Nagaslaev, Vladimir P.; /Fermilab; Sajaev, Vadim; /Argonne

2006-06-01T23:59:59.000Z

324

Experimental generation of ring-shaped beams with random sources  

E-Print Network (OSTI)

We have experimentally reproduced ring shaped beams from the scattered Laguerre-Gaussian and Bessel- Gaussian beams. A rotating ground glass plate is used as a scattering medium and a plano convex lens collects the scattered light to generate ring shaped beams at the Fourier plane. The experimental results are in good agreement with the theoretical results of Mei and Korotkova (Opt. Lett. 38, 91{93 (2013)).

Reddy, Salla Gangi; Prabhakar, Shashi; Singh, R P

2013-01-01T23:59:59.000Z

325

Finite Frobenius Rings and the MacWilliams Identities  

E-Print Network (OSTI)

Dublin November 14, 2011 #12;Finite Frobenius Rings (from last week) Finite ring R with 1. The (Jacobson) radical Rad(R) of R is the intersection of all maximal left ideals of R; Rad(R) is a two-sided ideal of R. The (left/right) socle Soc(R) of R is the ideal of R generated by all the simple left/right ideals of R. R

Wood, Jay

326

A matrix description for $K_1$ of graded rings.  

E-Print Network (OSTI)

The current paper is dedicated to the study of the classical $K$-theory of graded rings. Let $A$ be a $\\Gamma$ graded ring with identity 1, where the grading $\\Gamma$ is an abelian group. We associate a category with suspension to the $\\Gamma$ graded ring $A$, this allows us to generalize Bass' $K_1$ group to the setting of $\\Gamma$ graded rings. The generalized graded $K_1^{gr}$ is not only an abelian group but also a $\\mathbb Z[\\Gamma]$-module. Furthermore the generalization implies that there exists "locally" a matrix description for $K_1^{gr}$ of graded rings. The matrix description reveals a possibility for computing $K_1^{gr}$ of various types of graded rings. The generalized $K_1^{gr}$ satisfies the well known $K$-theory exact sequence $$ K_{1}^{gr}(A,I)\\to K_1^{gr}(A)\\to K_1^{gr}(A/I) $$ for any graded ideal $I$ of $A$. Finally, as an easy application, we compute $K^{gr}_1$ of cross products.

Zuhong Zhang

327

Atomic-phase interference devices based on ring-shaped Bose-Einstein condensates: Two ring case  

E-Print Network (OSTI)

We theoretically investigate the ground-state properties and quantum dynamics of a pair of adjacent ring-shaped Bose-Einstein condensates that are coupled via tunneling. This device, which is the analogue of a symmetric superconducting quantum interference device, is the simplest version of what we term an Atomic-Phase Interference Device (APHID). The two-ring APHID is shown to be sensitive to rotation.

B. P. Anderson; K. Dholakia; E. M. Wright

2002-09-10T23:59:59.000Z

328

Bifurcation analysis for phase transitions in superconducting rings with nonuniform thickness  

Science Conference Proceedings (OSTI)

Keywords: Ginzburg-Landau functional, Little-Parks experiment, superconducting rings, superconductivity

Jorge Berger; Jacob Rubinstein

1998-02-01T23:59:59.000Z

329

Control system for the turbomolecular pumping stations and sector valves of the CERN Intersecting Storage Rings  

E-Print Network (OSTI)

Control system for the turbomolecular pumping stations and sector valves of the CERN Intersecting Storage Rings

Gröbner, Oswald

1971-01-01T23:59:59.000Z

330

Adjudication Concerning the Turbomolecular Pumping Stations for the Vacuum System of the Intersecting Storage Rings  

E-Print Network (OSTI)

Adjudication Concerning the Turbomolecular Pumping Stations for the Vacuum System of the Intersecting Storage Rings

1968-01-01T23:59:59.000Z

331

HYDROBIOGEOCHEM: A coupled model of HYDROlogic transport and mixed BIOGEOCHEMical kinetic/equilibrium reactions in saturated-unsaturated media  

Science Conference Proceedings (OSTI)

The computer program HYDROBIOGEOCHEM is a coupled model of HYDROlogic transport and BIOGEOCHEMical kinetic and/or equilibrium reactions in saturated/unsaturated media. HYDROBIOGEOCHEM iteratively solves the two-dimensional transport equations and the ordinary differential and algebraic equations of mixed biogeochemical reactions. The transport equations are solved for all aqueous chemical components and kinetically controlled aqueous species. HYDROBIOGEOCHEM is designed for generic application to reactive transport problems affected by both microbiological and geochemical reactions in subsurface media. Input to the program includes the geometry of the system, the spatial distribution of finite elements and nodes, the properties of the media, the potential chemical and microbial reactions, and the initial and boundary conditions. Output includes the spatial distribution of chemical and microbial concentrations as a function of time and space, and the chemical speciation at user-specified nodes.

Yeh, G.T.; Salvage, K.M. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Civil and Environmental Engineering] [Pennsylvania State Univ., University Park, PA (United States). Dept. of Civil and Environmental Engineering; Gwo, J.P. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); Zachara, J.M.; Szecsody, J.E. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States)

1998-07-01T23:59:59.000Z

332

A Reaction-Transport Model for Calcite Precipitation andEvaluation of Infiltration Fluxes in unsaturated fractured rock  

Science Conference Proceedings (OSTI)

The percolation flux in the unsaturated zone (UZ) is an important parameter addressed in site characterization and flow and transport modeling of the potential nuclear-waste repository at Yucca Mountain, NV, USA. The US Geological Survey (USGS) has documented hydrogenic calcite abundances in fractures and lithophysal cavities at Yucca Mountain to provide constraints on percolation fluxes in the UZ. The purpose of this study was to investigate the relationship between percolation flux and measured calcite abundances using reactive transport modeling. Our model considers the following essential factors affecting calcite precipitation: (1) infiltration, (2) the ambient geothermal gradient, (3) gaseous CO2 diffusive transport and partitioning in liquid and gas phases, (4) fracture matrix interaction for water flow and chemical constituents, and (5) water rock interaction. Over a bounding range of 2 20 mm/year infiltration rate, the simulated calcite distributions capture the trend in calcite abundances measured in a deep borehole (WT-24) by the USGS. The calcite is found predominantly in fractures in the welded tuffs, which is also captured by the model simulations. Simulations showed that from about 2 to 6 mm/year, the amount of calcite precipitated in the welded Topopah Spring tuff is sensitive to the infiltration rate. This dependence decreases at higher infiltration rates owing to a modification of the geothermal gradient from the increased percolation flux. The model also confirms the conceptual model for higher percolation fluxes in the fractures compared to the matrix in the welded units, and the significant contribution of Ca from water rock interaction. This study indicates that reactive transport modeling of calcite deposition can yield important constraints on the unsaturated zone infiltration-percolation flux and provide useful insight into processes such as fracture matrix interaction as well as conditions and parameters controlling calcite deposition.

Xu, Tianfu; Sonnenthal, Eric; Bodvarsson, Gudmundur

2001-06-15T23:59:59.000Z

333

Injection, compression and stability of intense ion-rings  

SciTech Connect

Recent advances in pulsed high power ion beam technology make possible the creation of intense ion-rings with strong self-magnetic fields by single pulse injection. Such ion rings have several uses in controlled fusion e.g., to produce a min parallel B parallel magnetic geometry with a mirror ratio much higher than is possible with external conductors. For even stronger ion rings a min parallel B parallel with closed lines of force (ASTRON type) can be created. For this purpose, since the ion energies required are much higher than are available from high power sources, magnetic compression can be utilized to increase the ion energy. The success of this scheme depends critically on the stability of the ion ring. The low frequency perturbations of the ring-plasma system is examined by means of a generalization of the energy principle which established sufficient conditions for stability. The high-frequency micro- instabilities and their nonlinear consequences are discussed in terms of conventional techniques. (auth)

Sudan, R.N.

1975-01-01T23:59:59.000Z

334

Estimate of the coupling impedance for the storage rings of the NSLS  

SciTech Connect

The most important ingredient to evaluate the stability of a particle beam in a storage ring is the longitudinal coupling impedance Z/n and the transverse impedance Z/sub perpendicular/ which is usually associated to the former. These impedances are calculated for the two storage rings which are part of the NSLS, namely the Ultra Violet Ring (UVR) and the X-Ray Ring (XRR)-the parameters for these two rings which are used throughout the paper are shown.

Ruggiero, A.G.

1979-08-01T23:59:59.000Z

335

Relativistic klystron driven compact high gradient accelerator as an injector to an X-ray synchrotron radiation ring  

DOE Patents (OSTI)

A compact high gradient accelerator driven by a relativistic klystron is utilized to inject high energy electrons into an X-ray synchrotron radiation ring. The high gradients provided by the relativistic klystron enables accelerator structure to be much shorter (typically 3 meters) than conventional injectors. This in turn enables manufacturers which utilize high energy, high intensity X-rays to produce various devices, such as computer chips, to do so on a cost effective basis.

Yu, David U. L. (1912 MacArthur St., Rancho Palos Verdes, CA 90732)

1990-01-01T23:59:59.000Z

336

Combination ring cavity and backward Raman waveguide amplifier  

DOE Patents (OSTI)

A combination regenerative ring and backward Raman waveguide amplifier and a combination regenerative ring oscillator and backward Raman waveguide amplifier which produce Raman amplification, pulse compression, and efficient energy extraction from the CO.sub.2 laser pump signal for conversion into a Stokes radiation signal. The ring cavity configuration allows the CO.sub.2 laser pump signal and Stokes signal to copropagate through the Raman waveguide amplifier. The backward Raman waveguide amplifier configuration extracts a major portion of the remaining energy from the CO.sub.2 laser pump signal for conversion to Stokes radiation. Additionally, the backward Raman amplifier configuration produces a Stokes radiation signal which has a high intensity and a short duration. Adjustment of the position of overlap of the Stokes signal and the CO.sub.2 laser pump signal in the backward Raman waveguide amplifiers alters the amount of pulse compression which can be achieved.

Kurnit, Norman A. (Santa Fe, NM)

1983-01-01T23:59:59.000Z

337

DESIGN OF VISIBLE DIAGNOSTIC BEAMLINE FOR NSLS2 STORAGE RING  

SciTech Connect

A visible synchrotron light monitor (SLM) beam line has been designed at the NSLS2 storage ring, using the bending magnet radiation. A retractable thin absorber will be placed in front of the first mirror to block the central x-rays. The first mirror will reflect the visible light through a vacuum window. The light is guided by three 6-inch diameter mirrors into the experiment hutch. In this paper, we will describe design work on various optical components in the beamline. The ultra high brightness NSLS-II storage ring is under construction at Brookhaven National Laboratory. It will have 3GeV, 500mA electron beam circulating in the 792m ring, with very low emittance (0.9nm.rad horizontal and 8pm.rad vertical). The ring is composed of 30 DBA cells with 15 fold symmetry. Three damping wigglers will be installed in long straight sections 8, 18 and 28 to lower the emittance. While electrons pass through the bending magnet, synchrotron radiation will be generated covering a wide spectrum. There are other insertion devices in the storage ring which will generate shorter wavelength radiation as well. Synchrotron radiation has been widely used as diagnostic tool to measure the transverse and longitudinal profile. Three synchrotron light beam lines dedicated for diagnostics are under design and construction for the NSLS-II storage ring: two x-ray beam lines (pinhole and CRL) with the source points from Cell 22 BM{_}A (first bending in the DBA cell) and Cell22 three-pole wiggler; the third beam line is using visible part of radiation from Cell 30 BM{_}B (second bending magnet from the cell). Our paper focuses on the design of the visible beam line - SLM.

Cheng, W.; Fernandes, H.; Hseuh, H.; Kosciuk, B.; Krinsky, S.; Singh, O.

2011-03-28T23:59:59.000Z

338

Functionalization of multi-walled carbon nanotubes by epoxide ring-opening polymerization  

Science Conference Proceedings (OSTI)

In this study, covalent functionalization of carbon nanotubes (CNTs) was accomplished by surface-initiated epoxide ring-opening polymerization. FT-IR spectra showed that polyether and epoxide group covalently attached to the sidewalls of CNTs. TGA results indicated that the polyether was successfully grown from the CNT surface, with the final products having a polymer weight percentage of ca. 14-74 wt%. The O/C ratio of CNTs increased significantly from 5.1% to 29.8% after surface functionalization of CNTs. SEM and TEM images of functionalized CNTs exhibited that the tubes were enwrapped by polymer chains with thickness of several nanometers, forming core-shell structures with CNTs at the center. - Graphical abstract: Functionalized CNTs were enwrapped by polymer chains with thickness of several nanometers, forming core-shell structures with CNTs at the center. Highlights: Black-Right-Pointing-Pointer CNTs were functionalized by epoxide ring-opening polymerization. Black-Right-Pointing-Pointer Polyether and epoxide group covalently attached to the sidewalls of CNTs. Black-Right-Pointing-Pointer Functionalized CNTs have a polymer weight percentage of ca. 14-74 wt%. Black-Right-Pointing-Pointer Functionalized CNTs were enwrapped by polymer chains with thickness of several nanometers.

Jin Fanlong [School of Chemical and Materials Engineering, Jilin Institute of Chemical Technology, Jilin City 132022 (China); Rhee, Kyong Yop [Industrial Liaison Research Institute, Department of Mechanical Engineering, College of Engineering, Kyung Hee University, 446-701 Yongin (Korea, Republic of); Park, Soo-Jin, E-mail: sjpark@inha.ac.kr [Department of Chemistry, Inha University, Nam-gu, Incheon 402-751 (Korea, Republic of)

2011-12-15T23:59:59.000Z

339

Spin rotation of polarized beams in high energy storage ring  

E-Print Network (OSTI)

The equations for spin evolution of a particle in a storage ring are obtained considering contributions from the tensor electric and magnetic polarizabilities of the particle along with the contributions from spin rotation and birefringence effect in polarized matter of an internal target. % Study of the spin rotation and birefringence effects for a particle in a high energy storage ring provides for measurement both the spin-dependent real part of the coherent elastic zero-angle scattering amplitude and tensor electric (magnetic) polarizabilities.

V. G. Baryshevsky

2006-03-23T23:59:59.000Z

340

IMPEDANCE BUDGET FOR CRAB CAVITY IN MEIC ELECTRON RING  

SciTech Connect

The Medium Energy Electron-Ion Collider (MEIC) at Jefferson Lab has been envisioned as a first stage high energy particle accelerator beyond the 12 GeV upgrade of CEBAF. The estimate of impedance budget is important from the view point of beam stability and matching with other accelerator components driving currents. The detailed study of impedance budget for electron ring has been performed by considering the current design parameters of the e-ring. A comprehensive picture of the calculations involved in this study has been illustrated in the paper.

S. Ahmed, B. Yunn, G. Krafft

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Estimation of unsaturated zone traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential-flow model  

SciTech Connect

Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of these end members.

Brian A. Ebel; John R. Nimmo

2009-09-11T23:59:59.000Z

342

Turbine nozzle/nozzle support structure  

DOE Patents (OSTI)

An axial flow turbine`s nozzle/nozzle support structure is described having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse. 6 figs.

Boyd, G.L.; Shaffer, J.E.

1997-01-07T23:59:59.000Z

343

Turbine nozzle/nozzle support structure  

DOE Patents (OSTI)

An axial flow turbine`s nozzle/nozzle support structure is described having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse. 6 figs.

Boyd, G.L.; Shaffer, J.E.

1996-09-10T23:59:59.000Z

344

Turbine nozzle/nozzle support structure  

DOE Patents (OSTI)

An axial flow turbine`s nozzle/nozzle support structure is described having a cantilevered nozzle outer structure including an outer shroud and airfoil vanes extending radially inwardly therefrom, an inner shroud radially adjacent the inner end of the airfoil vanes and cooperatively disposed relative to the outer shroud to provide an annular fluid flow path, an inner and an outer support ring respectively arranged radially inside the inner shroud and axially adjacent a portion of the outer shroud, and pins extending through such portion and into the outer support ring. The inner support ring or inner shroud has a groove therein bounded by end walls for receiving and being axially abuttable with a locating projection from the adjacent airfoil vane, inner shroud, or inner support ring. The nozzle outer structure may comprise segments each of which has a single protrusion which is axially engageable with the outer support ring or, alternatively, a first and second protrusion which are arcuately and axially separated and which include axial openings therein whereby first and second protrusions on respective, arcuately adjacent nozzle segments have axial openings therein which are alignable with connector openings in the outer support ring and within each of such aligned openings a pin is receivable. The inner shroud may, likewise, comprise segments which, when assembled in operating configuration, have a 360 degree expanse. 6 figs.

Boyd, G.L.; Shaffer, J.E.

1995-08-15T23:59:59.000Z

345

Applications of the change-of-rings spectral sequence to the computation of Hochschild cohomology.  

E-Print Network (OSTI)

We consider the change-of-rings spectral sequence as it applies to Hochschild cohomology, obtaining a description of the differentials on the first page which relates it to the multiplicative stucture on cohomology. Using this information, we are able to completely describe the cohomology structure of monogenic algebras as well as some information on the structure of the cohomology in more general situations. We also show how to use the spectral sequence to reprove and generalize results of M. Auslander et. al. about homological epimorphisms. We derive from this a rather general version of the long exact sequence due to D. Happel for a one-point (co)-extension of a finite dimensional algebra and show how it can be put to use in concrete examples.

Mariano Suárez-Alvarez

346

Ring Bolted Joint NSTX-CALC-132-11  

E-Print Network (OSTI)

NSTX Ring Bolted Joint NSTX-CALC-132-11 Rev 0 March 2011 Prepared By assemblies which are connected through a stepped lap joint with four stainless steel bolts. These bolts, must provide sufficient compressive force, through combined preload, to resist the joint separation for all

Princeton Plasma Physics Laboratory

347

October 1988 SUPERCONDUCTING CAVITIES IN THE LIGHT SOURCE STORAGE RING  

E-Print Network (OSTI)

The synchrotron radiation loss in the Conceptual Design Report (CDR) storage ring at the design energy of 6 Ge. From beam tests conducted at Cornell and DESY, one may expect to obtain 10 MV per straight section: Maximum energy Bending magnet radiation loss per turn Insertion device loss per turn Sin ~s = 0

Kemner, Ken

348

Multi-ring performance of the Kendall square multiprocessor  

SciTech Connect

Performance of the hierarchical shared-memory system of the Kendall Square Research multiprocessor is measured and characterized. The performance of prefetch is measured. Latency, bandwidth, and contention are analyzed on a 4-ring, 128 processor system. Scalability comparisons are made with other shared-memory and distributed-memory multiprocessors.

Dunigan, T.H.

1994-03-01T23:59:59.000Z

349

Beam Loss Monitors for NSLS-II Storage Ring  

SciTech Connect

The shielding for the NSLS-II storage ring will provide adequate protection for the full injected beam losses in two cells of the ring around the injection point, but the remainder of the ring is shielded for lower losses of <10% top-off injection beam current. This will require a system to insure that beam losses do not exceed levels for a period of time that could cause excessive radiation exposure outside the shield walls. This beam Loss Control and Monitoring system will have beam loss monitors that will measure where the beam charge is lost around the ring, to warn operators if losses approach the design limits. To measure the charge loss quantitatively, we propose measuring the electron component of the shower as beam electrons hit the vacuum chamber (VC) wall. This will be done using the Cerenkov light as electrons transit ultra-pure fused silica rods placed close to the inner edge of the VC. The entire length of the rod will collect light from the electrons of the spread out shower resulting from the small glancing angle of the lost beam particles to the VC wall. The design and measurements results of the prototype Cerenkov BLM will be presented.

Kramer, S.L.; Cameron, P.

2011-03-28T23:59:59.000Z

350

Hooks generate the representation ring of the symmetric group  

E-Print Network (OSTI)

We prove that the representation ring of the symmetric group on $n$ letters is generated by the exterior powers of its natural $(n-1)$-dimensional representation. The proof we give illustrates a strikingly simple formula due to Y. Dvir. We provide an application and investigate a possible generalization of this result to some other reflection groups.

Marin, Ivan

2011-01-01T23:59:59.000Z

351

Black Strings, Black Rings and State-space Manifold  

E-Print Network (OSTI)

State-space geometry is considered, for diverse three and four parameter non-spherical horizon rotating black brane configurations, in string theory and $M$-theory. We have explicitly examined the case of unit Kaluza-Klein momentum $D_1D_5P$ black strings, circular strings, small black rings and black supertubes. An investigation of the state-space pair correlation functions shows that there exist two classes of brane statistical configurations, {\\it viz.}, the first category divulges a degenerate intrinsic equilibrium basis, while the second yields a non-degenerate, curved, intrinsic Riemannian geometry. Specifically, the solutions with finitely many branes expose that the two charged rotating $D_1D_5$ black strings and three charged rotating small black rings consort real degenerate state-space manifolds. Interestingly, arbitrary valued $M_5$-dipole charged rotating circular strings and Maldacena Strominger Witten black rings exhibit non-degenerate, positively curved, comprehensively regular state-space configurations. Furthermore, the state-space geometry of single bubbled rings admits a well-defined, positive definite, everywhere regular and curved intrinsic Riemannian manifold; except for the two finite values of conserved electric charge. We also discuss the implication and potential significance of this work for the physics of black holes in string theory.

Stefano Bellucci; Bhupendra Nath Tiwari

2010-10-19T23:59:59.000Z

352

PINOKY: a ring that animates your plush toys  

Science Conference Proceedings (OSTI)

PINOKY is a wireless ring-like device that can be externally attached to any plush toy as an accessory that animates the toy by moving its limbs. A user is thus able to instantly convert any plush toy into a soft robot. The user can control the toy remotely ... Keywords: interactive plush toy, robots, tangible user interface, ubiquitous computing

Yuta Sugiura; Calista Lee; Masayasu Ogata; Anusha Withana; Yasutoshi Makino; Daisuke Sakamoto; Masahiko Inami; Takeo Igarashi

2012-05-01T23:59:59.000Z

353

Loss-free method of charging accumulator rings  

SciTech Connect

A method for the production of high current pulses of heavy ions having an atomic weight greater than 100. Also a linear accelerator based apparatus for carrying out said method. Pulses formed by the method of the subject invention are suitable for storage in a storage ring. The accumulated pulses may be used in inertial fusion apparatus.

Maschke, Alfred W. (East Moriches, NY)

1979-01-01T23:59:59.000Z

354

Modelling structured domains using description graphs and logic programming  

Science Conference Proceedings (OSTI)

Although OWL 2 is widely used to describe complex objects such as chemical molecules, it cannot represent ‘structural' features of chemical entities (e.g., having a ring). A combination of rules and description graphs (DGs) has been proposed ...

Despoina Magka; Boris Motik; Ian Horrocks

2012-05-01T23:59:59.000Z

355

The cohomology structure of string algebras.  

E-Print Network (OSTI)

We show that the graded commutative ring structure of the Hochschild cohomology HH*(A) is trivial in case A is a triangular quadratic string algebra. Moreover, in case A isgentle, the Lie algebra structure on HH*(A) is also trivial.

Juan Carlos Bustamante

356

Infrared absorption measurements of the kinetics of Cl atom reactions with C{sub 3}H{sub n} (n=4,6) unsaturated hydrocarbons between 300-850 K  

Science Conference Proceedings (OSTI)

The reaction of chlorine (Cl) atoms with the unsaturated C{sub 3}H{sub n} where n=4,6, hydrocarbons propylene, allene, and methyl acetylene have been uninvestigated as a function of temperature and pressure.

Farrell, J.T.; Pilgrim, J.S.; Taatjes, C.A.

1997-08-01T23:59:59.000Z

357

On the role of delocalization in benzene: Theoretical and experimental investigation of the effects of strained ring fusion  

Science Conference Proceedings (OSTI)

When an important compound`s discovery dates back as far as 1825, one would imagine that every facet of its chemical and physical properties has been illuminated in the meantime. Benzene, however, has not ceased to challenge the chemist`s notion of structure and bonding since its first isolation by Michael Faraday. This report is divided into the following six chapters: 1. Aromaticity -- Criteria, manifestations, structural limitations; 2. The role of delocalization in benzene; 3. The thermochemical properties of benzocyclobutadienologs; 4. Ab initio study of benzenes fused to four-membered rings; 5. Non-planar polycyclic aromatic hydrocarbons; and 6. Experimental details and input decks. 210 Refs.

Faust, R. [Lawrence Berkeley Lab., CA (United States). Chemical Sciences Div.]|[California Univ., Berkeley, CA (United States). Dept. of Chemistry

1993-04-01T23:59:59.000Z

358

ISG8-Structures  

NLE Websites -- All DOE Office Websites (Extended Search)

Structures (WG4) Structures (WG4) Orange Rm H. Carter, T. Higo and J. Wang Parallel Sessions: Working Groups: WG1: Parameters, Design, Instrumentation and Tuning WG2: Damping Rings and ATF WG3: RF Sources WG4:Structures WG5: Ground Motion; Site Requirements and Investigations Goals Review of progress and experiences in design and fabrication. Review of high gradient tests. R&D plan and schedule through spring of 2003. Plan and schedule for production of 8-pack structures. Plan and schedule to document how to manufacture and process NLC/JLC accelerator structures. Preliminary Agenda Monday 9:00 Plenary 10:30 Coffee Break 11:00 – 12:00 Working Group Organization Opening Remarks - Dave Burke, Ron Ruth, Nobu Toge Discussion: Agenda and working group organization Lunch 13:30 – 15:30 High Gradient Test (Joint session with WG3)

359

Colloid Transport and Deposition in Water-Saturated and Unsaturated Sand and Yucca Mountain Tuff: Effect of Ionic Strength and Moisture Saturation  

Science Conference Proceedings (OSTI)

Colloid-aided radionuclide transport has been considered a potentially important mechanism for the candidate spent fuel and high level waste (HLW) repository at Yucca Mountain. This mechanism, however, has not been treated in Yucca Mountain Total System Performance Assessments (TSPAs) until recently. Even then there has been little discussion of possible colloid retention in the unsaturated zone. This report summarizes investigations of potential colloid retention in sand and Yucca Mountain tuff as a fun...

1999-12-03T23:59:59.000Z

360

User`s Guide: Database of literature pertaining to the unsaturated zone and surface water-ground water interactions at the Idaho National Engineering Laboratory  

SciTech Connect

Since its beginnings in 1949, hydrogeologic investigations at the Idaho National Engineering Laboratory (INEL) have resulted in an extensive collection of technical publications providing information concerning ground water hydraulics and contaminant transport within the unsaturated zone. Funding has been provided by the Department of Energy through the Department of Energy Idaho Field Office in a grant to compile an INEL-wide summary of unsaturated zone studies based on a literature search. University of Idaho researchers are conducting a review of technical documents produced at or pertaining to the INEL, which present or discuss processes in the unsaturated zone and surface water-ground water interactions. Results of this review are being compiled as an electronic database. Fields are available in this database for document title and associated identification number, author, source, abstract, and summary of information (including types of data and parameters). AskSam{reg_sign}, a text-based database system, was chosen. WordPerfect 5.1{copyright} is being used as a text-editor to input data records into askSam.

Hall, L.F.

1993-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Gulf Stream Simulations and the Dynamics of Ring and Meander Processes  

Science Conference Proceedings (OSTI)

We present here a regional, eddy resolving, numerical study of the dynamics of Gulf Stream Meander and Ring (GSMR) interaction processes. We initialize the Harvard quasi-geostrophic open-boundary model with realistic meander and ring locations as ...

Allan R. Robinson; Michael A. Spall; Nadia Pinardi

1988-12-01T23:59:59.000Z

362

Frequency of Ring Separations from the Loop Current in the Gulf of Mexico: A Revised Estimate  

Science Conference Proceedings (OSTI)

The most energetic events in the circulation of the Gulf of Mexico are the separation of large anticyclonic rings from the Loop Current. Building on previous work, the authors examine all the apparent rings since July 1973. This new dataset ...

W. Sturges; R. Leben

2000-07-01T23:59:59.000Z

363

Piston ring pack design effects on production spark ignition engine oil consumption : a simulation analysis  

E-Print Network (OSTI)

One of the most significant contributors to an engine's total oil consumption is the piston ring-pack. As a result, optimization of the ring pack is becoming more important for engine manufacturers and lubricant suppliers. ...

Senzer, Eric B

2007-01-01T23:59:59.000Z

364

New waveguide-type HOM damper for ALS storage ring cavities.  

E-Print Network (OSTI)

WAVEGUIDE-TYPE HOM DAMPER FOR ALS STORAGE RING CAVITIES*.CA, 94720, USA Abstract The ALS storage ring 500 MHz RFoperations issue at the ALS. During three consecutive

Kwiatkowski, Slawomir; Baptiste, Kenneth; Julian, James

2004-01-01T23:59:59.000Z

365

The effect of surface finish on piston ring-pack performance in advanced reciprocating engine systems  

E-Print Network (OSTI)

Frictional losses in the piston ring-pack of an engine account for approximately 20% of the total frictional losses within an engine. Methods of surface texture optimization were investigated to reduce piston ring-pack ...

Jocsak, Jeffrey (Jeffrey Alan)

2005-01-01T23:59:59.000Z

366

Modeling the lubrication of the piston ring pack in internal combustion engines using the deterministic method  

E-Print Network (OSTI)

Piston ring packs are used in internal combustion engines to seal both the high pressure gas in the combustion chamber and the lubricant oil in the crank case. The interaction between the piston ring pack and the cylinder ...

Chen, Haijie

2011-01-01T23:59:59.000Z

367

Effects of lubricant viscosity and surface texturing on ring-pack performance in internal combustion engines  

E-Print Network (OSTI)

The piston ring-pack contributes approximately 25% of the mechanical losses in an internal combustion engine. Both lubricant viscosity and surface texturing were investigated in an effort to reduce this ring-pack friction ...

Takata, Rosalind (Rosalind Kazuko), 1978-

2006-01-01T23:59:59.000Z

368

Dual-band reflectarrays using microstrip ring elements and their applications with various feeding arrangements  

E-Print Network (OSTI)

In recent years there has been a growing demand for reduced mass, small launch volume, and, at the same time, high-gain large-aperture antenna systems in modern space-borne applications. This dissertation introduces new techniques for dual-band reflectarray antennas to meet these requirements. A series of developments is presented to show the dual-band capability of the reflectarray. A novel microstrip ring structure has been developed to achieve circular polarization (CP). A C/Ka dual-band front-fed reflectarray antenna has been designed to demonstrate the dual-band circular polarized operation. The proposed ring structure provides many advantages of compact size, more freedom in the selection of element spacing, less blockage between circuit layers, and broader CP bandwidth as compared to the patches. An X/Ka dual-band offset-fed reflectarray is made of thin membranes, with their thickness equal to 0.0508 mm in both layers. Several degrading effects of thin substrates are discussed. To overcome these problems, a new configuration is developed by inserting empty spaces of the proper thickness below both the X and Ka band membranes. More than 50 % efficiencies are achieved at both frequency ranges, and the proposed scheme is expected to be a good candidate to meet the demand for future inflatable antenna systems. An X/Ka dual-band microstrip reflectarray with circular polarization has also been constructed using thin membranes and a Cassegrain offset-fed configuration. It is believed that this is the first Cassegrain reflectarray ever developed. This antenna has a 0.75-meter-diameter aperture and uses a metallic sub-reflector and angular-rotated annular ring elements. It achieved a measured 3 dB gain bandwidth of 700 MHz at Xband and 1.5 GHz at Ka-band, as well as a CP bandwidth (3 dB axial ratio) of more than 700 MHz at X-band and more than 2 GHz at Ka-band. The measured peak efficiencies are 49.8 % at X-band and 48. 2 % at Ka-band. In summary, this dissertation presents a series of new research developments to support the dual-band operation of the reflectarray antenna. The results of this work are currently being implemented onto a 3-meter reflectarray with inflatable structures at the Jet Propulsion Laboratory and are planned for other applications such as an 8-meter inflatable reflectarray in the near future.

Han, Chul Min

2006-08-01T23:59:59.000Z

369

Coherent Region-, Species-, and Frequency-Dependent Local Climate Signals in Northern Hemisphere Tree-Ring Widths  

Science Conference Proceedings (OSTI)

Patterns of correlation between tree rings and local temperature or precipitation are investigated using 762 International Tree-Ring Data Bank standardized ring width site chronology time series, and a gridded dataset of temperature and ...

Justin J. Wettstein; Jeremy S. Littell; John M. Wallace; Ze’ev Gedalof

2011-12-01T23:59:59.000Z

370

The Mean and Near-Inertial Velocity Fields in a Warm-Core Ring  

Science Conference Proceedings (OSTI)

Velocity and temperature profiles collected in warm-core ring 82-I in January 1983 are used to describe the mean and fluctuating fields of the ring. The ring was relatively small, containing no Sargasso See water. Its signature vanished below 600 ...

Eric Kunze

1986-08-01T23:59:59.000Z

371

Effect of eccentricity and boundary conditions on the edge superconducting states in mesoscopic rings  

Science Conference Proceedings (OSTI)

It is considered a mesoscopic superconductor ring in the presence of an external magnetic field applied in the direction perpendicular to the ring plane. The internal and external edges have circular form but they are excentric, the excentricity being ... Keywords: De Gennes extrapolation length, Edge superconductivity, Mesoscopic superconductor rings

E. Moncada; F. Segovia; J. C. Granada

2008-03-01T23:59:59.000Z

372

Non-Contact Haptic Feedback Using Air Vortex Rings Sidhant Gupta1,2  

E-Print Network (OSTI)

regions of the human body. Author Keywords Non-contact haptic feedback; air vortex rings ACM1 AirWave: Non-Contact Haptic Feedback Using Air Vortex Rings Sidhant Gupta1,2 , Dan Morris1 feedback into such interaction. In this work, we explore the use of air vortex rings for this purpose

Rajamani, Sriram K.

373

Ground vibration model studies for APS storage ring  

SciTech Connect

An analytical ground vibration model is developed for study of the vibration effects on the beam motion in the Advanced Photon Source (APS) storage ring. The different physical parameters associated with the wave characteristics and the vibration modes needed for the study are taken from the vibration studies carried out at the APS site. The implementation has been carried out using Mathematica{trademark}. The study is carried out for the frequency range 1--35 Hz, with a number of sources changing from one through ten. The program written in Mathematica{trademark}, calculates orbit distortion, beta wave change, tune change, dispersion change, and chromaticity change. However, the main parameter studied for the APS storage ring has been the orbit distortion. The merit factor associated with different modes excited by the vibrations has been calculated.

Koul, R.K.

1994-07-01T23:59:59.000Z

374

MINIMUM EMITTANCE LATTICE FOR SYNCHROTRON RADIATION STORAGE RINGS  

NLE Websites -- All DOE Office Websites (Extended Search)

MINIMUM EMITTANCE LATTICE FOR MINIMUM EMITTANCE LATTICE FOR SYNCHROTRON RADIATION STORAGE RINGS 1. C. Teng ANL/FNAL LS-17 L. Teng March 18, 1985 The natural emittance of an electron beam in a storage ring is given by (see e.g., M. Sands, SLAC 21) (1) where Cq =~~= 3.832 x 10-l3 m 32/3 mc J x partition factor in the bending plane y = total energy in mc 2 uni ts p orbit radius in bending magnets (assumed the same in all magne ts) H yn 2 - + 2ann ' + Bn I 2 ( a, B, Y = betatron functions ) n, n I dispersion functions <> = averaging over bending magnets We shall calculate for each bending magnet, then average over all magnets. 2 A. General Expression for H This can be calculated in a straightforward manner, but we can save a great deal of arithmetic with some preliminary formal analytical

375

Experiences with permanent magnets at the Fermilab recycler ring  

E-Print Network (OSTI)

In order to achieve higher luminosities in Run II a separate antiproton storage ring was built in the Main Injector tunnel. To reduce both construction and operations costs permanent magnets were used. This paper discusses the design criterion and specifications, including temperature dependence, longitudinal uniformity, and adjusting of the higher harmonics of the magnets. The design tolerances for a storage ring are more stringent than for a single pass beam line. The difference between the measured and ideal central field for each magnet was held to better than 0.1%. The temperature stability for all magnets was set to better than 0.01% per degree Celsius. Higher order harmonics relative to the central field were set to less than 0.01%. This was done for all 484 permanent magnet that were built.

Volk, James T

2012-01-01T23:59:59.000Z

376

The Ring Imaging Cherenkov detector (RICH) of the AMS experiment  

E-Print Network (OSTI)

The Alpha Magnetic Spectrometer (AMS) experiment to be installed on the International Space Station (ISS) will be equipped with a proximity focusing Ring Imaging Cherenkov (RICH) detector for measuring the electric charge and velocity of the charged cosmic particles. A RICH prototype consisting of 96 photomultiplier units, including a piece of the conical reflector, was built and its performance evaluated with ion beam data. Preliminary results of the in-beam tests performed with ion fragments resulting from collisions of a 158 GeV/c/nuc primary beam of Indium ions (CERN SPS) on a Pb target are reported. The collected data included tests to the final front-end electronics and to different aerogel radiators. Cherenkov rings for a large range of charged nuclei and with reflected photons were observed. The data analysis confirms the design goals. Charge separation up to Fe and velocity resolution of the order of 0.1% for singly charged particles are obtained.

F. Barao; M. Aguilar Benitez; J. Alcaraz; L. Arruda; A. Barrau; G. Barreira; E. Belmont; J. Berdugo; M. Brinet; M. Buenerd; D. Casadei; J. Casaus; E. Cortina; C. Delgado; C. Diaz; L. Derome; L. Eraud; R. J. Garcia-Lopez; L. Gallin-Martel; F. Giovacchini; P. Goncalves; E. Lanciotti; G. Laurenti; A. Malinine; C. Mana; J. Marin; G. Martinez; A. Menchaca-Rocha; M. Molla; C. Palomares; M. Panniello; R. Pereira; M. Pimenta; K. Protasov; E. Sanchez; E-S. Seo; N. Sevilla; A. Torrento; M. Vargas-Trevino; O. Veziant

2006-03-31T23:59:59.000Z

377

Future Synchrotron Light Sources Based on Ultimate Storage Rings  

Science Conference Proceedings (OSTI)

The main purpose of this talk is to describe how far one might push the state of the art in storage ring design. The talk will start with an overview of the latest developments and advances in the design of synchrotron light sources based on the concept of an 'ultimate' storage ring. The review will establish how bright a ring based light source might be, where the frontier of technological challenges are, and what the limits of accelerator physics are. Emphasis will be given to possible improvements in accelerator design and developments in technology toward the goal of achieving an ultimate storage ring. An ultimate storage ring (USR), defined as an electron ring-based light source having an emittance in both transverse planes at the diffraction limit for the range of X-ray wavelengths of interest for a scientific community, would provide very high brightness photons having high transverse coherence that would extend the capabilities of X-ray imaging and probe techniques beyond today's performance. It would be a cost-effective, high-coherence 4th generation light source, competitive with one based on energy recovery linac (ERL) technology, serving a large number of users studying material, chemical, and biological sciences. Furthermore, because of the experience accumulated over many decades of ring operation, it would have the great advantage of stability and reliability. In this paper we consider the design of an USR having 10-pm-rad emittance. It is a tremendous challenge to design a storage ring having such an extremely low emittance, a factor of 100 smaller than those in existing light sources, especially such that it has adequate dynamic aperture and beam lifetime. In many ultra-low emittance designs, the injection acceptances are not large enough for accumulation of the electron beam, necessitating on-axis injection where stored electron bunches are completely replaced with newly injected ones. Recently, starting with the MAX-IV 7-bend achromatic cell, we have made significant progress with the design of PEP-X, a USR that would inhabit the decommissioned PEP-II tunnel at SLAC. The enlargement of the dynamic aperture is largely a result of the cancellations of the 4th-order resonances in the 3rd-order achromats and the effective use of lattice optimization programs. In this paper, we will show those cancellations of the 4th-order resonances using an analytical approach based on the exponential Lie operators and the Poisson brackets. Wherever possible, our analytical results will be compared with their numerical counterparts. Using the derived formulae, we will construct 4th-order geometric achromats and use them as modules for the lattice of the PEP-X USR, noting that only geometric terms are canceled to the 4th order.

Cai, Yunhai; /SLAC

2012-04-09T23:59:59.000Z

378

Investigation and simulation of muon cooling rings with tilted solenoids  

DOE Green Energy (OSTI)

Alternating solenoid focused muon cooling ring without special bending magnets is considered and investigate in detail. Both fringe field between solenoid coils with opposite directed current, and an inclination of the coils in vertical plane are used to provide a bending and closing of the particle trajectories. Realistic (Maxwellian) magnetic field is calculated and used for a simulation. Methodic is developed and applied to find closed orbit at any energy, dispersion, region of stability, and other conventional accelerator characteristics. Earlier proposed RFOFO cooling ring with 200 MHz RF system and liquid hydrogen absorbers is investigated in detail. After an optimization, normalized 6D emittance about 20 mm{sup 3} and transmission 57% are obtained.

Valeri I. Balbekov

2003-05-28T23:59:59.000Z

379

Ring type dumped packing saving 30% on tower cost  

SciTech Connect

This article discusses the packing problems of a flue gas processing plant that recovers 90,000 lb/hr of carbon dioxide for use in an enhanced oil recovery (EOR) project. A concentrated absorption solution was needed to keep the liquid circulation low, and a packing with low pressure drop and high effective surface area was needed to keep the fan horsepower and column size down and minimize the amount of CO/sub 2/ that slips through the column. The solution was to use a high concentration CO/sub 2/ recovery solvent and a proprietary ring type packing was used which gives 50% less pressure drop than conventional packing and provides high efficiency. Carbon steel packing rings were used except for two sections.

Wiggins, W.R. III; Hodel, A.E.

1984-02-01T23:59:59.000Z

380

HOM Power Generation and Propagation in the PEP II Rings  

SciTech Connect

Most of the HOM power that propagates in the PEP-II rings is generated in the RF cavities but its content in terms of TE and TM components has not been accurately determined. For purpose of estimating power deposition at the cavity HOM loads, and also of shielding beamline components such as bellows from TE power penetration, this HOM power content and its distribution profile around the rings are needed. We calculate the TE and TM contributions of the RF cavity to the circulating HOM power and their transmission properties at another cavity downstream. By taking into account the generation in, and scattering by the cavities, as well as the attenuation along the vacuum chamber, a realistic estimate of the HOM power propagating out of a RF station is obtained. The formulation can include the HOM contributions of other beamline components such as collimators.

Lin, Xintian; Ng, Cho-Kuen; Ko, Kwok; /SLAC

2011-08-26T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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381

Low energy proton storage ring with longitudinal magnetic  

E-Print Network (OSTI)

Proton energy 1,75 MeV Energy spread ±3,2 % = ±56 keV (2) Current (DC) 100 mkA Transverse size ±10 mm (2Low energy proton storage ring with longitudinal magnetic field and electron cooling M.I. Bryzgunov energy protons. In this particular case it is reaction for production of resonant gamma-quant (9.17 Me

382

FODO/DOUBLET LATTICE FOR THE SNS ACCUMULATOR RING.  

SciTech Connect

Requirements of minimum beam loss for hand-on maintenance and flexibility for future operations are essential for the lattice design of the Spallation Neutron Source (SNS) accumulator ring. In this paper, we present a hybrid lattice that consists of FODO arcs and doublet straights, emphasizing injection and collimation optimization and flexibility, split tunes for coupling control, sextupole families for chromaticity control, and compatibility to future upgrades.

WEI,J.; GARDNER,C.; LEE,Y.Y.; TSOUPAS,N.

2000-06-30T23:59:59.000Z

383

Ion polarization in the MEIC figure-8 ion collider ring  

SciTech Connect

The nuclear physics program envisaged at the Medium-energy Electron-Ion Collider (MEIC) currently being developed at the Jefferson Lab calls for collisions of 3-11 GeV/c longitudinally polarized electrons and 20-100 GeV/c, in equivalent proton momentum, longitudinally/ transversely polarized protons/ deuterons/ light ions. We present a scheme that provides the required ion polarization arrangement in the MEIC's ion collider ring.

V.S. Morozov, Ya.S. Derbenev, Y. Zhang, P. Chevtsov, A.M. Kondratenko, M.A. Kondratenko, Yu.N. Filatov

2012-07-01T23:59:59.000Z

384

Experimental determination of gravitomagnetic effects by means of ring lasers  

E-Print Network (OSTI)

A new experiment aimed to the detection of the gravito-magnetic Lense-Thirring effect at the surface of the Earth will be presented; the name of the experiment is GINGER. The proposed technique is based on the behavior of light beams in ring lasers, also known as gyrolasers. A three-dimensional array of ringlasers will be attached to a rigid monument; each ring will have a different orientation in space. Within the space-time of a rotating mass the propagation of light is indeed anisotropic; part of the anisotropy is purely kinematical (Sagnac effect), part is due to the interaction between the gravito-electric field of the source and the kinematical motion of the observer (de Sitter effect), finally there is a contribution from the gravito-magnetic component of the Earth (gravito-magnetic frame dragging or Lense-Thirring effect). In a ring laser a light beam traveling counterclockwise is superposed to another beam traveling in the opposite sense. The anisotropy in the propagation leads to standing waves with slightly different frequencies in the two directions; the final effect is a beat frequency proportional to the size of the instrument and its effective rotation rate in space, including the gravito-magnetic drag. Current laser techniques and the performances of the best existing ring lasers allow at the moment a sensitivity within one order of magnitude of the required accuracy for the detection of gravito-magnetic effects, so that the objective of GINGER is in the range of feasibility and aims to improve the sensitivity of a couple of orders of magnitude with respect to present. The experiment will be underground, probably in the Gran Sasso National Laboratories in Italy, and is based on an international collaboration among four Italian groups, the Technische Universitaet Muenchen and the University of Canterbury in Christchurch (NZ).

Angelo Tartaglia

2012-12-12T23:59:59.000Z

385

Mixtures of Bose Gases Confined in a Ring Potential  

SciTech Connect

The rotational properties of a mixture of two distinguishable Bose gases that are confined in a ring potential provide novel physical effects that we demonstrate in this study. Persistent currents are shown to be stable for a range of the population imbalance between the two components at low angular momentum. At higher values of the angular momentum, even small admixtures of a second species of atoms make the persistent currents highly fragile.

Smyrnakis, J.; Kavoulakis, G. M.; Magiropoulos, M. [Technological Education Institute of Crete, P.O. Box 1939, GR-71004, Heraklion (Greece); Bargi, S.; Kaerkkaeinen, K.; Reimann, S. M. [Mathematical Physics, Lund Institute of Technology, P.O. Box 118, SE-22100 Lund (Sweden)

2009-09-04T23:59:59.000Z

386

Thermoset polymers via ring opening metathesis polymerization of functionalized oils  

DOE Patents (OSTI)

The invention provides a method for producing a thermosetting resin from renewable oils, the method comprising supplying renewable oil molecules containing strained ring alkene moieties; reacting the alkene moieties with cyclic alkenes to create a polymer; and repeating the above two steps until the resin having desired characteristics are obtained. Also provided is a thermoset resin comprising functionalized renewable oil polymerized with a co-monomer.

Larock, Richard C; Henna, Phillip H; Kessier, Michael R

2012-11-27T23:59:59.000Z

387

Ring-imaging Cerenkov studies. Final performance report  

SciTech Connect

This project involved collaboration in the design, construction and testing of a prototype chamber capable of detecting Cerenkov rings. The chamber incorporated several novel techniques in that it used parallel-plate pad readout and a Cesium-iodide (CsI) solid photocathode. The pad system used gas multiplication where the gas was kept at low pressure to minimize photon losses due to absorption and back-scattering and to minimize ion collection times. Low pressure also lowers the chamber response to charged particles. The chamber gas was ethane at 20 torr and the chamber was operated at room temperature. The chamber was built at the University of Pennsylvania by a University of Puerto Rico graduate student, Jorge Millan. Initial tests at Pennsylvania using a hydrogen-discharge lamp indicated a quantum efficiency of 13% at 190 nm. The chamber was then tested in the M-Test beam line at Fermilab and behind the C3 beamline dump at Brookhaven Lab. Cerenkov rings were clearly observed with each photoelectron typically exciting one pad. On average each ring had five struck pads and only 10% of the events had hits in the center due to the charged particle. These results indicate that a RICH detector using a solid CsI photocathode coupled to a low-pressure, parallel-plate pad chamber is an excellent device for particle identification in high-rate environments when there is a need to cover large areas with minimum expense.

Lopez, A.M.

1997-03-13T23:59:59.000Z

388

A distribution of the temperature in a ring of the incompressible, viscous liquid with two free boundaries. Exact solutions  

E-Print Network (OSTI)

It has been found the exact solutions for nonstationary distribution of the temperature in the liquid ring with two viscosities and two free boundaries of the ring.

N. F. Belmetsev; V. O. Bytev

2009-11-13T23:59:59.000Z

389

A PULSED MODULATOR POWER SUPPLY FOR THE G-2 MUON STORAGE RING INJECTION KICKER.  

DOE Green Energy (OSTI)

This paper describes the pulse modulator power supplies used to drive the kicker magnets that inject the muon beam into the 8-2 storage ring that has been built at Brookhaven National Laboratory. Three modulators built into coaxial structures consisting of a series circuit of an energy storage capacitor, a damping resistor and a fast thyratron switch are used to energize three magnets that kick the beam into the proper orbit. A 100 kV charging power supply is used to charge the capacitor to 95kV. The damping resistor shapes the magnet current waveform to a 450 nanosecond half-sine to match the injection requirements. This paper discusses the modulator design, construction and operation.

MI,J.LEE,Y.Y.MORSE,W.M.PAI,C.I.PAPPAS,G.C.SANDERS,Y.SEMERTIZIDIS,Y.,ET AL.

2003-03-01T23:59:59.000Z

390

A Pulsed Modulator Power Supply for the g-2 Muon Storage Ring Injection Kicker  

DOE Green Energy (OSTI)

This paper describes the pulse modulator power supplies used to drive the kicker magnets that inject the muon beam into the g-2 storage ring that has been built at Brookhaven. Three modulators built into coaxial structures consisting of a series circuit of an energy storage capacitor, damping resistor and a fast thyratron switch are used to energize three magnets that kick the beam into the proper orbit. A 100 kV charging power supply is used to charge the capacitor to 95 kV. the damping resistor shapes the magnet current waveform to a 450 nanosecond half-sine to match the injection requirements. this paper discusses the modulator design, construction and operation.

Mi,J.; Lee, Y.Y.; Morse, W. M.; Pai, C.; Pappas, G.; Sanders, R.; Semertzidis, Y.

1999-03-29T23:59:59.000Z

391

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing?  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Rotaxanes are mechanically interlocked molecular architectures consisting of a dumbbell-shaped molecule, the "axle," that threads through a ring called a macrocycle. Because the rings can spin around and slide along the axle, rotaxanes are promising components of molecular machines. While most rotaxanes have been entirely organic, the physical properties desirable in molecular machines are mostly found in inorganic compounds. Working together, two British groups at the University of Edinburgh and the University of Manchester have bridged this gap with hybrid rotaxanes, in which inorganic rings encircle the organic axles. The hybrid architecture greatly increases their range of useful physical properties, such as the magnetism based on molecular magnets that may make them suitable as qubits for quantum computers.

392

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing?  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Rotaxanes are mechanically interlocked molecular architectures consisting of a dumbbell-shaped molecule, the "axle," that threads through a ring called a macrocycle. Because the rings can spin around and slide along the axle, rotaxanes are promising components of molecular machines. While most rotaxanes have been entirely organic, the physical properties desirable in molecular machines are mostly found in inorganic compounds. Working together, two British groups at the University of Edinburgh and the University of Manchester have bridged this gap with hybrid rotaxanes, in which inorganic rings encircle the organic axles. The hybrid architecture greatly increases their range of useful physical properties, such as the magnetism based on molecular magnets that may make them suitable as qubits for quantum computers.

393

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing?  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Rotaxanes are mechanically interlocked molecular architectures consisting of a dumbbell-shaped molecule, the "axle," that threads through a ring called a macrocycle. Because the rings can spin around and slide along the axle, rotaxanes are promising components of molecular machines. While most rotaxanes have been entirely organic, the physical properties desirable in molecular machines are mostly found in inorganic compounds. Working together, two British groups at the University of Edinburgh and the University of Manchester have bridged this gap with hybrid rotaxanes, in which inorganic rings encircle the organic axles. The hybrid architecture greatly increases their range of useful physical properties, such as the magnetism based on molecular magnets that may make them suitable as qubits for quantum computers.

394

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing?  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Rotaxanes are mechanically interlocked molecular architectures consisting of a dumbbell-shaped molecule, the "axle," that threads through a ring called a macrocycle. Because the rings can spin around and slide along the axle, rotaxanes are promising components of molecular machines. While most rotaxanes have been entirely organic, the physical properties desirable in molecular machines are mostly found in inorganic compounds. Working together, two British groups at the University of Edinburgh and the University of Manchester have bridged this gap with hybrid rotaxanes, in which inorganic rings encircle the organic axles. The hybrid architecture greatly increases their range of useful physical properties, such as the magnetism based on molecular magnets that may make them suitable as qubits for quantum computers.

395

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing?  

NLE Websites -- All DOE Office Websites (Extended Search)

Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Hybrid Rotaxanes: Interlocked Structures for Quantum Computing? Print Rotaxanes are mechanically interlocked molecular architectures consisting of a dumbbell-shaped molecule, the "axle," that threads through a ring called a macrocycle. Because the rings can spin around and slide along the axle, rotaxanes are promising components of molecular machines. While most rotaxanes have been entirely organic, the physical properties desirable in molecular machines are mostly found in inorganic compounds. Working together, two British groups at the University of Edinburgh and the University of Manchester have bridged this gap with hybrid rotaxanes, in which inorganic rings encircle the organic axles. The hybrid architecture greatly increases their range of useful physical properties, such as the magnetism based on molecular magnets that may make them suitable as qubits for quantum computers.

396

Status of the ATF Damping Ring BPM Upgrade Project  

Science Conference Proceedings (OSTI)

A substantial upgrade of the beam position monitors (BPM) at the ATF (Accelerator Test Facility) damping ring is currently in progress. Implementing digital read-out signal processing techniques in line with an optimized, low-noise analog downconverter, a resolution well below 1 mum could be demonstrated at 20 (of 96) upgraded BPM stations. The narrowband, high resolution BPM mode permits investigation of all types of non-linearities, imperfections and other obstacles in the machine which may limit the very low target aimed vertical beam emittance of < 2 pm. The technical status of the project, first beam measurements and an outlook to it's finalization are presented.

Briegel, C.; /Fermilab; Eddy, N.; /Fermilab; Haynes, B.; /Fermilab; May, J.; /SLAC; McCormick, D.; /SLAC; Nelson, J.; /SLAC; Nicklaus, D.; /Fermilab; Prieto, P.; /Fermilab; Rechenmacher, R.; /Fermilab; Smith, T.; /SLAC; Teranuma, N.; /KEK, Tsukuba; Urakawa, J.; /KEK, Tsukuba; Voy, D.; /Fermilab; Wendt, M.; /Fermilab; Woodley, M.; /SLAC

2011-12-01T23:59:59.000Z

397

The SLD Cerenkov Ring Imaging Detector: Progress report  

Science Conference Proceedings (OSTI)

We describe test beam results from a prototype Cerenkov Ring Imaging Detector (CRID) for the SLD experiment at the SLAC Linear Collider (SLC). The system includes both liquid and gas radiators, a long drift box containing gaseous TMAE and a proportional wire chamber with charge division readout. Measurements of the multiplicity and detection resolution of Cerenkov photons, from both radiators are presented. Various design aspects of a new engineering prototype, currently under construction, are discussed and recent R and D results relevant to this effort are reported.

Ashford, V.; Bienz, T.; Bird, F.; Crawford, G.; Gaillard, M.; Hallewell, G.; Leith, D.; McShurley, D.; Nuttall, A.; Oxoby, G.

1986-10-01T23:59:59.000Z

398

Reliability analysis for LEB ring magnet power system in SSC  

Science Conference Proceedings (OSTI)

The LEB ring magnet power system contains six subsystems, supervisory control, power supplies, regulation, DC bus, resonant cells, and fault sensing network. The system availability of the total LEB RMPS is required to be 0.999. The work in this paper is to allocate the overall LEB RMPS reliability requirement into reliability requirements for each of the subsystems and lower-tier items. The Feasibility-of-Objective technique combining with engineering experience is the key for the allocation. MIL-HDBK-217F is used to derate SCR components. 7 refs., 5 figs.

Smedley, K.

1991-11-01T23:59:59.000Z

399

Optical distortions in electron/positron storage rings  

SciTech Connect

We have studied the optical distortions in the PEP electron/positron storage ring for various optical configurations using the computer programs DIMAT, HARMON, PATRICIA, and TURTLE. The results are shown graphically by tracing several thousand trajectories from one interaction region to the next using TURTLE and by tracing a few selected rays several hundred turns using the programs DIMAT and PATRICIA. The results show an interesting correlation between the calculated optical cleanliness of a particular lattice configuration and the observed operating characteristics of the machine.

Brown, K.L.; Donald, M.; Servranckx, R.

1983-01-01T23:59:59.000Z

400

Radiation Damage of Polypropylene Fiber Targets in Storage Rings  

E-Print Network (OSTI)

Thin polypropylene (CH$_2$) fibers have been used for internal experiments in storage rings as an option for hydrogen targets. The change of the hydrogen content due to the radiation dose applied by the circulating proton beam has been investigated in the range $1\\cdot10^6$ to $2\\cdot10^8$~Gy at beam momenta of 1.5 to 3 GeV/c by comparing the elastic pp-scattering yield to that from inelastic p-carbon reactions. It is found that the loss of hydrogen as a function of applied dose receives contributions from a fast and a slow component.

H. Rohdjess; D. Albers; J. Bisplinghoff; R. Bollmann; K. Buesser; O. Diehl; F. Dohrmann; H. -P. Engelhardt; P. D. Eversheim; J. Greiff; A. Gross; R. Gross-Hardt; F. Hinterberger; M. Igelbrink; R. Langkau; R. Maier; F. Mosel; M. Mueller; M. Muenstermann; D. Prasuhn; P. von Rossen; H. Scheid; N. Schirm; F. Schwandt; W. Scobel; H. J. Trelle; A. Wellinghausen; W. Wiedmann; K. Woller; R. Ziegler

2004-03-23T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Black Holes in Higher Dimensions (Black Strings and Black Rings)  

E-Print Network (OSTI)

The main focus of this session was the presentation of new higher-dimensional black hole solutions, including black rings, black strings, and multi black holes, and the study of their properties. Besides new asymptotically flat and locally asymptotically flat black objects also new black holes with anti-de Sitter asymptotics were reported. The studies of their properties included the investigation of their stability, their thermodynamics, their analyticity and their existence. Furthermore, the geodesics in such higher-dimensional space-times were investigated.

Kunz, Jutta

2013-01-01T23:59:59.000Z

402

5D Black Rings and 4D Black Holes  

E-Print Network (OSTI)

It has recently been shown that the M theory lift of a IIA 4D BPS Calabi-Yau black hole is a 5D BPS black hole spinning at the center of a Taub-NUT-flux geometries, and a certain linear relation between 4D and 5D BPS partition functions was accordingly proposed. In the present work we fortify and enrich this proposal by showing that the M-theory lift of the general 4D multi-black hole geometry are 5D black rings in a Taub-NUT-flux geometry.

Davide Gaiotto; Andrew Strominger; Xi Yin

2005-04-14T23:59:59.000Z

403

Using Ring Laser Systems to Measure Gravitomagnetic Effects on Earth  

E-Print Network (OSTI)

Gravitomagnetic effects originates from the rotation of the source of the gravitational field and from the rotational features of the observers' frame. In recent years, gravitomagnetism has been tested by means of its impact on the precession of LAGEOS orbits and on the precession of spherical gyroscopes in the GP-B experiment. What we suggest here is that light can be used as a probe to test gravitomagnetic effects in an terrestrial laboratory: the proposed detector consists of large ring-lasers arranged along three orthogonal axes.

Matteo Luca Ruggiero

2013-11-22T23:59:59.000Z

404

Transverse instability of the antiproton beam in the Recycler Ring  

SciTech Connect

The brightness of the antiproton beam in Fermilab's 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.

Prost, L.R.; Bhat, C.M.; Burov, A.; Crisp, J.; Eddy, N.; Hu, M.; Shemyakin, A.; /Fermilab

2011-03-01T23:59:59.000Z

405

Influence of Atmospheric Pressure and Water Table Fluctuations on Gas Phase Flow and Transport of Volatile Organic Compounds (VOCs) in Unsaturated Zones  

E-Print Network (OSTI)

Understanding the gas phase flow and transport of volatile organic compounds (VOCs) in unsaturated zones is indispensable to develop effective environmental remediation strategies, to create precautions for fresh water protection, and to provide guidance for land and water resources management. Atmospheric pressure and water table fluctuations are two important natural processes at the upper and lower boundaries of the unsaturated zone, respectively. However, their significance has been neglected in previous studies. This dissertation systematically investigates their influence on the gas phase flow and transport of VOCs in soil and ground water remediation processes using analytically and numerically mathematical modeling. New semi-analytical and numerical solutions are developed to calculate the subsurface gas flow field and the gas phase transport of VOCs in active soil vapor extraction (SVE), barometric pumping (BP) and natural attenuation taking into account the atmospheric pressure and the water table fluctuations. The accuracy of the developed solutions are checked by comparing with published analytical solutions under extreme conditions, newly developed numerical solutions in COMSOL Multiphysics and field measured data. Results indicate that both the atmospheric pressure and the tidal-induced water table fluctuations significantly change the gas flow field in active SVE, especially when the vertical gas permeability is small (less than 0.4 Darcy). The tidal-induced downward moving water table increases the depth-averaged radius of influence (ROI) for the gas pumping well. However, this downward moving water table leads to a greater vertical pore gas velocity away from the gas pumping well, which is unfavorable for removing VOCs. The gas flow rate to/from the barometric pumping well can be accurately calculated by our newly developed solutions in both homogeneous and multi-layered unsaturated zones. Under natural unsaturated zone conditions, the time-averaged advective flux of the gas phase VOCs induced by the atmospheric pressure and water table fluctuations is one to three orders of magnitude less than the diffusive flux. The time-averaged advective flux is comparable with the diffusive flux only when the gas-filled porosity is very small (less than 0.05). The density-driven flux is negligible.

You, Kehua

2013-05-01T23:59:59.000Z

406

NA Standards | Valence Geometries | Bond Angles-Furanose Rings  

NLE Websites -- All DOE Office Websites (Extended Search)

angles in Furanose Rings angles in Furanose Rings ----------------------------------------------------- ribose deoxyribose ----------------------------------------------------- angle mean esd N mean esd N value value ----------------------------------------------------- C1'-C2'-C3' 101.5 (0.9, 80) 102.7 (1.4, 47) C2'-C3'-C4' 102.7 (1.0, 80) 103.2 (1.0, 47) C3'-C4'-O4' 105.5 (1.4, 80) 105.6 (1.0, 47) C4'-O4'-C1' 109.6 (0.9, 80) 109.7 (1.4, 47) O4'-C1'-C2' 106.4 (1.4, 80) 106.1 (1.0, 47) C1'-C2'-O2' 110.6 (3.0, 80) na C3'-C2'-O2' 113.3 (2.9, 80) na C2'-C3'-O3' 111.0 (2.8, 80) 110.6 (2.7, 47) C4'-C3'-O3' 110.6 (2.6, 80) 110.3 (2.2, 47) C5'-C4'-C3' 115.5 (1.5, 80) 114.7 (1.5, 47)

407

Operational advances in ring current modeling using RAM-SCB  

Science Conference Proceedings (OSTI)

The Ring current Atmosphere interaction Model with Self-Consistently calculated 3D Magnetic field (RAM-SCB) combines a kinetic model of the ring current with a force-balanced model of the magnetospheric magnetic field to create an inner magnetospheric model that is magnetically self consistent. RAM-SCB produces a wealth of outputs that are valuable to space weather applications. For example, the anisotropic particle distribution of the KeV-energy population calculated by the code is key for predicting surface charging on spacecraft. Furthermore, radiation belt codes stand to benefit substantially from RAM-SCB calculated magnetic field values and plasma wave growth rates - both important for determining the evolution of relativistic electron populations. RAM-SCB is undergoing development to bring these benefits to the space weather community. Data-model validation efforts are underway to assess the performance of the system. 'Virtual Satellite' capability has been added to yield satellite-specific particle distribution and magnetic field output. The code's outer boundary is being expanded to 10 Earth Radii to encompass previously neglected geosynchronous orbits and allow the code to be driven completely by either empirical or first-principles based inputs. These advances are culminating towards a new, real-time version of the code, rtRAM-SCB, that can monitor the inner magnetosphere conditions on both a global and spacecraft-specific level. This paper summarizes these new features as well as the benefits they provide the space weather community.

Welling, Daniel T [Los Alamos National Laboratory; Jordanova, Vania K [Los Alamos National Laboratory; Zaharia, Sorin G [Los Alamos National Laboratory; Morley, Steven K [Los Alamos National Laboratory

2010-12-03T23:59:59.000Z

408

Proceedings of the workshop on polarized targets in storage rings  

Science Conference Proceedings (OSTI)

Polarization phenomena have played an increasingly important part in the study of nuclei and nucleons in recent years. Polarization studies have been hampered by the relatively few and rather fragile polarized targets which are presently available. The concept of polarized gas targets in storage rings opens a much wider range of possibilities than is available in the external target geometry. This novel method will represent a considerable advance in nuclear physics and will continue to receive much attention in plans for future facilities. An internal, polarized-target station is being planned for the cooler ring at the Indiana University Cyclotron Facility. Internal targets are compatible with recent designs of electron accelerators proposed by the Massachusetts Institute of Technology and the Southeastern Universities Research Association. The key to nuclear-science programs based on internal targets pivots on recent developments in polarized atomic beam methods, which include the more recent laser-driven polarized targets. The workshop drew together a unique group of physicists in the fields of high-energy, nuclear and atomic physics. The meeting was organized in a manner that stimulated discussion among the 58 participants and focused on developments in polarized target technology and the underlying atomic physics. An impressive array of future possibilities for polarized targets as well as current developments in polarized target technology were discussed at the workshop. Abstracts of individual items from the workshop were prepared separately for the data base.

Holt, R.J. (ed.)

1984-08-01T23:59:59.000Z

409

Orbit Stability Improvement At The Nsls X-Ray Ring  

E-Print Network (OSTI)

We describe recent improvements in both the short and long-term orbit stability at the NSLS X-Ray Ring. The short-term stability has been improved by increasing the gain and the bandwidth of the global harmonic feedback systems. The long-term horizontal orbit drift over the course of a fill has been reduced by including the rf-frequency in the orbit feedback. Work is in progress to further reduce orbit drift by compensating for thermally induced mechanical motions of the beam position monitors (BPMs). I. INTRODUCTION At the NSLS storage rings, the harmonic based analog global feedback system has provided excellent orbit stability [1]. For most users, the level of this beam stability (short and long-term) has been satisfactory, however, further stabilization is desirable. During the Fall of 1994, the gain and bandwidth of the global feedback systems were increased resulting in significantly reduced short-term orbit fluctuations. The long-term drift in the horizontal orbit has been red...

Safranek Singh And; J. Safranek; O. Singh; L. Solomon

1996-01-01T23:59:59.000Z

410

Polynomial fusion rings of W-extended logarithmic minimal models  

E-Print Network (OSTI)

The countably infinite number of Virasoro representations of the logarithmic minimal model LM(p,p') can be reorganized into a finite number of W-representations with respect to the extended Virasoro algebra symmetry W. Using a lattice implementation of fusion, we recently determined the fusion algebra of these representations and found that it closes, albeit without an identity for p>1. Here, we provide a fusion-matrix realization of this fusion algebra and identify a fusion ring isomorphic to it. We also consider various extensions of it and quotients thereof, and introduce and analyze commutative diagrams with morphisms between the involved fusion algebras and the corresponding quotient polynomial fusion rings. One particular extension is reminiscent of the fundamental fusion algebra of LM(p,p') and offers a natural way of introducing the missing identity for p>1. Working out explicit fusion matrices is facilitated by a further enlargement based on a pair of mutual Moore-Penrose inverses intertwining between the W-fundamental and enlarged fusion algebras.

Jorgen Rasmussen

2008-12-05T23:59:59.000Z

411

LIFETIME PREDICTION FOR MODEL 9975 O-RINGS IN KAMS  

SciTech Connect

The Savannah River Site (SRS) is currently storing plutonium materials in the K-Area Materials Storage (KAMS) facility. The materials are packaged per the DOE 3013 Standard and transported and stored in KAMS in Model 9975 shipping packages, which include double containment vessels sealed with dual O-rings made of Parker Seals compound V0835-75 (based on Viton{reg_sign} GLT). The outer O-ring of each containment vessel is credited for leaktight containment per ANSI N14.5. O-ring service life depends on many factors, including the failure criterion, environmental conditions, overall design, fabrication quality and assembly practices. A preliminary life prediction model has been developed for the V0835-75 O-rings in KAMS. The conservative model is based primarily on long-term compression stress relaxation (CSR) experiments and Arrhenius accelerated-aging methodology. For model development purposes, seal lifetime is defined as a 90% loss of measurable sealing force. Thus far, CSR experiments have only reached this target level of degradation at temperatures {ge} 300 F. At lower temperatures, relaxation values are more tolerable. Using time-temperature superposition principles, the conservative model predicts a service life of approximately 20-25 years at a constant seal temperature of 175 F. This represents a maximum payload package at a constant ambient temperature of 104 F, the highest recorded in KAMS to date. This is considered a highly conservative value as such ambient temperatures are only reached on occasion and for short durations. The presence of fiberboard in the package minimizes the impact of such temperature swings, with many hours to several days required for seal temperatures to respond proportionately. At 85 F ambient, a more realistic but still conservative value, bounding seal temperatures are reduced to {approx}158 F, with an estimated seal lifetime of {approx}35-45 years. The actual service life for O-rings in a maximum wattage package likely lies higher than the estimates due to the conservative assumptions used for the model. For lower heat loads at similar ambient temperatures, seal lifetime is further increased. The preliminary model is based on several assumptions that require validation with additional experiments and longer exposures at more realistic conditions. The assumption of constant exposure at peak temperature is believed to be conservative. Cumulative damage at more realistic conditions will likely be less severe but is more difficult to assess based on available data. Arrhenius aging behavior is expected, but non-Arrhenius behavior is possible. Validation of Arrhenius behavior is ideally determined from longer tests at temperatures closer to actual service conditions. CSR experiments will therefore continue at lower temperatures to validate the model. Ultrasensitive oxygen consumption analysis has been shown to be useful in identifying non-Arrhenius behavior within reasonable test periods. Therefore, additional experiments are recommended and planned to validate the model.

Hoffman, E.; Skidmore, E.

2009-11-24T23:59:59.000Z

412

Quantum ring solitons and nonlocal effects in plasma wake field excitations  

Science Conference Proceedings (OSTI)

A theoretical investigation of the quantum transverse beam motion for a cold relativistic charged particle beam travelling in a cold, collisionless, strongly magnetized plasma is carried out. This is done by taking into account both the individual quantum nature of the beam particles (single-particle uncertainty relations and spin) and the self consistent interaction generated by the plasma wake field excitation. By adopting a fluid model of a strongly magnetized plasma, the analysis is carried out in the overdense regime (dilute beams) and in the long beam limit. It is shown that the quantum description of the collective transverse beam dynamics is provided by a pair of coupled nonlinear governing equations. It comprises a Poisson-like equation for the plasma wake potential (driven by the beam density) and a 2D spinorial Schroedinger equation for the wave function, whose squared modulus is proportional to the beam density, that is obtained in the Hartree's mean field approximation, after disregarding the exchange interactions. The analysis of this pair of equations, which in general exhibits a strong nonlocal character, is carried out analytically as well as numerically in both the linear and the nonlinear regimes, showing the existence of the quantum beam vortices in the form of Laguerre-Gauss modes and ring envelope solitons, respectively. In particular, when the relation between the plasma wake field response and the beam probability density is strictly local, the pair of the governing equations is reduced to the 2D Gross-Pitaevskii equation that allows one to establish the conditions for the self focusing and collapse. These conditions include the quantum nature of the beam particles. Finally, when the relation between the plasma wake field response and the beam probability density is moderately nonlocal, the above pair of equations permits to follow the spatio-temporal evolution of a quantum ring envelope soliton. Such a structure exhibits small or violent breathing, but it remains very stable for long time.

Fedele, R.; Tanjia, F. [Dipartimento di Scienze Fisiche, Universita di Napoli 'Federico II', and INFN, Napoli (Italy); De Nicola, S. [Dipartimento di Scienze Fisiche, Universita di Napoli 'Federico II', and INFN, Napoli (Italy); Istituto Nazionale di Ottica - C. N. R., Pozzuoli (Italy); Jovanovic, D. [Institute of Physics, University of Belgrade, Belgrade (Serbia); Shukla, P. K. [Center of Advanced Studies in Physical Sciences, Ruhr-Universitaet Bochum, Bochum (Germany)

2012-10-15T23:59:59.000Z

413

Unsaturated Zone I. Overview  

E-Print Network (OSTI)

waste management program in addition to the site-characterization efforts at Yucca Mountain Upwelling at Yucca Mountain The Board completed its review of material (11 re- ports) first submitted that there is evidence of ongoing, intermittent hydrothermal upwelling at Yucca Mountain and that large earth- quake

414

A STUDY ON THE CHOICE OF PARAMETERS FOR A HIGH ENERGY ELECTRON RING ACCELERATOR  

SciTech Connect

The production of high energy (multi-GeV) proton beams by an electron ring accelerator is considered. Both the final energy and intensity of the proton beam depend on the choice of parameters for the electron ring. Possible sets of parameters, consistent with all the known requirements of ring stability, and which optimize the energy and (or) the intensity of the proton beam, are presented.

Bovet, C.; Pellegrini, C.

1970-06-26T23:59:59.000Z

415

A dynamical comparison between the rings R(X) and R X Afef Ellouz (1  

E-Print Network (OSTI)

for proving results on R via passage to R(X). 1 D´epartement de Math´ematiques, Facult´e des Sciences de SfaxA dynamical comparison between the rings R(X) and R X Afef Ellouz (1 ), Henri Lombardi (2 ), Ihsen Yengui (3 ) March 11, 2007 Abstract We prove that for any ring R with Krull dimension d, the ring R X

Lombardi, Henri

416

Non-free extensions of the simplex codes over a chain ring with four elements  

Science Conference Proceedings (OSTI)

Let R be a chain ring with four elements. In this paper, we present two new constructions of R-linear codes that contain a subcode associated with a simplex code over the ring R. The simplex codes are defined as the codes generated ... Keywords: 51C05, 51E21, 51E26, 94B05, 94B27, Chain ring, Gray map, Hjelmslev plane, Hyperoval, Lee weight, Projective Hjelmslev space, R-linear code, Simplex code

Thomas Honold; Ivan Landjev

2013-01-01T23:59:59.000Z

417

The Study of Stress Corrosion Cracking on Alloy 600 C-Ring ...  

Science Conference Proceedings (OSTI)

... (SCC) have been investigated in stressed C-rings of Alloy 600 boiler tubing. .... INFLUENCE OF PRIMARY WATER CHEMISTRY ON OXIDES FORMED ON ...

418

FODO-Supercell Based Compact Ring Design with Tunable Momentum Compaction and Optimized Dynamic Aperture  

Science Conference Proceedings (OSTI)

A storage ring with tunable momentum compaction has the advantage in achieving different RMS bunch length with similar RF capacity, which is potentially useful for many applications, such as linear collider damping ring and predamping ring where injected beam has a large energy spread and a large transverse emittance. A tunable bunch length also makes the commissioning and fine tuning easier in manipulating the single bunch instabilities. In this paper, a compact ring design based on a supercell is presented, which achieves a tunable momentum compaction while maintaining a large dynamic aperture.

Sun, Yipeng; /SLAC

2012-05-03T23:59:59.000Z

419

FODO-Supercell Based Compact Ring Design with Tunable Momentum Compaction and Optimized Dynamic Aperture  

Science Conference Proceedings (OSTI)

A storage ring with tunable momentum compaction has the advantage in achieving different RMS bunch length with similar RF capacity, which is potentially useful for many applications, such as linear collider damping ring and pre-damping ring where injected beam has a large energy spread and a large transverse emittance. A tunable bunch length also makes the commissioning and fine tuning easier in manipulating the single bunch instabilities. In this paper, a compact ring design based on a supercell is presented, which achieves a tunable momentum compaction while maintaining a large dynamic aperture.

Sun, Yipeng; /SLAC

2012-05-11T23:59:59.000Z

420

Adsorption of Single-ring Model Naphthenic Acid from Oil Sands ...  

Science Conference Proceedings (OSTI)

Presentation Title, Adsorption of Single-ring Model Naphthenic Acid from Oil Sands Tailings Pond Water Using Petroleum Coke-derived Activated Carbon.

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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421

Elementary-Particle Propagation via 3-Scale ``Towers of Quartet Rings'' Within a Dyonic History Lattice  

E-Print Network (OSTI)

Massless elementary-particle propagation is represented historically (cosmologically) through 3-scale ``towers of quartet rings'' within a lattice of magneto-electrodynamically communicating ``pre-events''. The lightlike intervals within a ring of 4 pre-events (discrete ``closed string'') display transverse GUT-scale and longitudinal ``particle scale''. The lightlike (longitudinal) spacing between successive rings of a tower is at Planck scale. Ratio between GUT scale and Planck scale relates quantum-dynamically to elementary magnetic charge. Permutations of a ring quartet, in conjunction with Lorentz-group representations, control elementary-particle quantum numbers.

G. F. Chew

1999-01-28T23:59:59.000Z

422

A Performance Comparison of Tree and Ring Topologies in Distributed System  

Science Conference Proceedings (OSTI)

A distributed system is a collection of computers that are connected via a communication network. Distributed systems have become commonplace due to the wide availability of low-cost, high performance computers and network devices. However, the management infrastructure often does not scale well when distributed systems get very large. Some of the considerations in building a distributed system are the choice of the network topology and the method used to construct the distributed system so as to optimize the scalability and reliability of the system, lower the cost of linking nodes together and minimize the message delay in transmission, and simplify system resource management. We have developed a new distributed management system that is able to handle the dynamic increase of system size, detect and recover the unexpected failure of system services, and manage system resources. The topologies used in the system are the tree-structured network and the ring-structured network. This thesis presents the research background, system components, design, implementation, experiment results and the conclusions of our work. The thesis is organized as follows: the research background is presented in chapter 1. Chapter 2 describes the system components, including the different node types and different connection types used in the system. In chapter 3, we describe the message types and message formats in the system. We discuss the system design and implementation in chapter 4. In chapter 5, we present the test environment and results, Finally, we conclude with a summary and describe our future work in chapter 6.

Min Huang

2005-12-19T23:59:59.000Z

423

AGING PERFORMANCE OF MODEL 9975 PACKAGE FLUOROELASTOMER O-RINGS  

Science Conference Proceedings (OSTI)

The influence of temperature and radiation on Viton{reg_sign} GLT and GLT-S fluoroelastomer O-rings is an ongoing research focus at the Savannah River National Laboratory. The O-rings are credited for leaktight containment in the Model 9975 shipping package used for transportation of plutonium-bearing materials. At the Savannah River Site, the Model 9975 packages are being used for interim storage. Primary research efforts have focused on surveillance of O-rings from actual packages, leak testing of seals at bounding aging conditions and the effect of aging temperature on compression stress relaxation behavior, with the goal of service life prediction for long-term storage conditions. Recently, an additional effort to evaluate the effect of aging temperature on the oxidation of the materials has begun. Degradation in the mechanical properties of elastomers is directly related to the oxidation of the polymer. Sensitive measurements of the oxidation rate can be performed in a more timely manner than waiting for a measurable change in mechanical properties, especially at service temperatures. Measuring the oxidation rate therefore provides a means to validate the assumption that the degradation mechanisms(s) do not change from the elevated temperatures used for accelerated aging and the lower service temperatures. Monitoring the amount of oxygen uptake by the material over time at various temperatures can provide increased confidence in lifetime predictions. Preliminary oxygen consumption analysis of a Viton GLT-based fluoroelastomer compound (Parker V0835-75) using an Oxzilla II differential oxygen analyzer in the temperature range of 40-120 C was performed. Early data suggests oxygen consumption rates may level off within the first 100,000 hours (10-12 years) at 40 C and that sharp changes in the degradation mechanism (stress-relaxation) are not expected over the temperature range examined. This is consistent with the known long-term heat aging resistance of fluoroelastomers relative to hydrocarbon-based elastomers, and in absence of antioxidants that may be consumed over time. Additional experimental effort will be undertaken in the short term range within the first 100 hours of thermal aging to capture further details of the oxygen consumption rate.

Hoffman, E.; Daugherty, W.; Skidmore, E.; Dunn, K.; Fisher, D.

2011-05-31T23:59:59.000Z

424

Nature's approach toward ring formation and structural diversity in ergot alkaloid biosynthesis  

E-Print Network (OSTI)

Ergot alkaloids are fungal-derived secondary metabolites well known for a diverse array of pharmacological effects both beneficial and detrimental to human health. Historically, the ergot alkaloids have been known to cause ...

Cheng, Johnathan Zandrew

2011-01-01T23:59:59.000Z

425

FRP Retrofit of the Ring-Beam of a Nuclear Reactor Containment Structure  

E-Print Network (OSTI)

to reconfigure the plant? #12;16.810 (16.682) 5 Life Cycle: Conceive, Design, Implement 1 Beginning of Lifecycle Manufacturing Plant Warehouse PF1 ... PFn QA1 ... QAn Parts Buffer Supplier Buffer Assembly Final Inspection cool Injection Molding - mainly polymers Layup ­ e.g. Pre-preg composite manufacturing Sintering - form

426

Structural Transformations Accompanying the Assembly of Bacteriophage P22 Portal Protein Rings in Vitro*  

E-Print Network (OSTI)

conditions. At the conventional scale, flow over long and intermediate size pin fins/pillars/tube bundles hasAli Kosar1 Mechatronics Engineering Program, SabanciUniversity, Orhanli, Tuzla, Istanbul, 34956 fittings. A pressure difference between the inlet and the exit chambers pumps the flow through the micro

Prevelige Jr., Peter E.

427

All Ring Tech Co Ltd | Open Energy Information  

Open Energy Info (EERE)

Co Ltd Co Ltd Jump to: navigation, search Name All Ring Tech Co Ltd Place Kaohsiung, Taiwan Product Engaged in the manufacture and sale of semiconductor equipment, passive element equipment, thin film transistor liquid crystal display (TFT-LCD) equipment, optoelectronic products and venturing into thin-film PV manufacturing equipment. Coordinates 22.672569°, 120.293228° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":22.672569,"lon":120.293228,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

428

Optomechanics with molecules in a strongly pumped ring cavity  

E-Print Network (OSTI)

Cavity cooling of an atom works best on a cyclic optical transition in the strong coupling regime near resonance, where small cavity photon numbers suffice for trapping and cooling. Due to the absence of closed transitions a straightforward application to molecules fails: optical pumping can lead the particle into uncoupled states. An alternative operation in the far off-resonant regime generates only very slow cooling due to the reduced field-molecule coupling. We predict to overcome this by using a strongly driven ring-cavity operated in the sideband cooling regime. As in the optomechanical setups one takes advantage of a collectively enhanced field-molecule coupling strength using a large photon number. A linearized analytical treatment confirmed by full numerical quantum simulations predicts fast cooling despite the off-resonant small single molecule - single photon coupling. Even ground state cooling can be obtained by tuning the cavity field close to the Anti-stokes sideband for sufficiently high trappi...

Schulze, R J; Ritsch, H

2010-01-01T23:59:59.000Z

429

3D-Simulation Studies of SNS Ring Doublet Magnets  

SciTech Connect

The accumulator ring of the Spallation Neutron Source (SNS) at ORNL employs in its straight sections closely packed quadrupole doublemagnets with large aperture of R=15.1 cm an relatively short iron-to-iron distance of 51.4 cm. These quads have much extended fringe field, and magnetic interferences among them in the doublet assemblies is not avoidable. Though each magnet in the assemblies has been individually mapped to high accuracy of lower than 0.01 percent level, the experimental data including the magnetic interference effect will not be available. We have performed 3D computing simulations on a quadrupole doublet model in order to assess the degree of the interference and to obtain relevant data for the SNS commissioning and operation.

Wang, J.G.; Tsoupas N.; Venturini, M.

2005-05-05T23:59:59.000Z

430

Impedance Calculations for the NSLS-II Storage Rings  

Science Conference Proceedings (OSTI)

Impedance of two vacuum chamber components, Bellows and BPM, is considered in some detail. In order to avoid generation of Higher-Order Modes (HOM's) in the NSLS-II bellows, we designed a new low-impedance RF shielding consisting of 6 wide and 2 narrow metal plates without opening slots between them. The short-range wakepotential has been optimized taking into account vertical offset of RF fingers from their nominal position. The results were compared with data of bellows designed at other laboratories. Narrow-band impedance of the BPM Button has been studied. TE-modes in the BPM button were suppressed by a factor of 8 by modification of existing housings. Two new types of housings are shown. The total impedance of the NSLS-II storage ring is discussed in terms of the loss factor and the vertical kick factor for a 3mm-Gaussian bunch.

Blednykh,A.; Ferreira, M.; Krinsky, S.

2009-05-04T23:59:59.000Z

431

Radiative polarization in high-energy storage rings  

SciTech Connect

Electron and positron beams circulating in high-energy storage rings become spontaneously polarized by the emission of synchrotron radiation. The asymptotic degree of polarization that can be attained is strongly affected by so-called depolarizing resonances. Detailed experimental measurements of the polarization were made SPEAR about ten years ago, but due to lack of a suitable theory only a limited theoretical fit to the data has so far been achieved. I present a general formalism for calculating depolarizing resonances, which as been coded into a computer program called SMILE, and use it to fit the SPEAR data. By the use of suitable approximations, I am able to fit both higher order and nonlinear resonances, and thereby to interpret many hitherto unexplained features in the data, and to resolve a puzzle concerning the asymmetry of certain resonance widths seen in the data. 18 refs., 2 figs.

Mane, S.R.

1989-03-01T23:59:59.000Z

432

Viability of a National HVDC Transmission Ring in India  

E-Print Network (OSTI)

The paper presents the current scenario in India as regards the EHV AC and DC transmission backbone systems. The ultimate goal of the transmission sector is to create an integrated national power system grid for the effective distribution of electrical energy throughout the country. This paper proposes HVDC as an attractive alternative for the transformation of the network from independent regional grids to a fully integrated national grid, and details how the existing, decided and planned HVDC systems could be utilised in such a scheme. A conceptual scheme and control strategy is presented to achieve an HVDC national ring-main. Advantages of such a scheme in terms of its reliability, controllability and immunity to different grid disturbances are enumerated. The paper also outlines the challenges involved in terms of algorithms required for control coordination among different HVDC links and load despatch centres for achieving such a system.

Mata Prasad; Rebati Dass; S. Chakravorty; Carl-göte Carlsson; Göran Isacsson; Asea Brown; Power System Engineering

1999-01-01T23:59:59.000Z

433

Spin Motion and Resonances in Accelerators and Storage Rings  

SciTech Connect

Some of the basic aspects of the spin dynamics of accelerators and storage rings are reviewed. Since the components of spin parallel and perpendicular to the particle velocity behave differently it is desirable to reformulate the equations of spin motion in a frame of reference that exhibits this difference explicitly. The conventional treatment employs a coordinate system derived from a reference orbit. An alternate coordinate system, based on the actual trajectory of the particle, leads to simplified equations of spin motion but, contrary to a conjecture presented in a previous note, resonance strengths calculated by the conventional and the revised formalisms are identical, as pointed out by Kondratenko. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.

Courant,E.

2008-01-01T23:59:59.000Z

434

Configuration Studies and Recommendations for the ILC DampingRings  

Science Conference Proceedings (OSTI)

We describe the results of studies comparing different options for the baseline configuration of the ILC damping rings. The principal configuration decisions apply to the circumference, beam energy, lattice type, and technology options for key components, including the injection/extraction kickers and the damping wigglers. To arrive at our recommended configuration, we performed detailed studies of a range of lattices representing a variety of different configuration options; these lattices are described in Chapter 2. The results of the various studies are reported in chapters covering issues of beam dynamics, technical subsystems, costs, and commissioning, reliability and upgrade ability. Our detailed recommendations for the baseline configuration are given in Chapter 7, where we also outline further research and development that is needed before a machine using our recommended configuration can be built and operated successfully. In the same chapter, we suggest possible alternatives to the baseline configuration.

Wolski, Andrzej; Gao, Jie; Guiducci, Susanna

2006-02-04T23:59:59.000Z

435

Graphene Layer Growth Chemistry: Five-Six-Ring Flip Reaction  

DOE Green Energy (OSTI)

A theoretical study revealed a new reaction pathway, in which a fused five and six-membered ring complex on the zigzag edge of a graphene layer isomerizes to reverse its orientation, or 'flips,' after activation by a gaseous hydrogen atom. The process is initiated by hydrogen addition to or abstraction from the surface complex. The elementary steps of the migration pathway were analyzed using density-functional theory (DFT) calculations to examine the region of the potential energy surface associated with the pathway. The DFT calculations were performed on substrates modeled by the zigzag edges of tetracene and pentacene. Rate constants for the flip reaction were obtained by the solution of energy master equation utilizing the DFT energies, frequencies, and geometries. The results indicate that this reaction pathway is competitive with other pathways important to the edge evolution of aromatic species in high temperature environments.

Whitesides, Russell; Domin, Dominik; Lester Jr., William A.; Frenklach, Michael

2007-03-24T23:59:59.000Z

436

SPECTROSCOPIC STUDIES OF IMPLODING PLASMA RINGS IN DETONABLE GAS MIXTURES  

DOE Green Energy (OSTI)

Spectroscopic observations were made of the flow field behind a cylindrical hypersonic wave front resulting from an imploding electrical dischange into an initially low pressure quiescert gas. Sub-microsecond resolved spectra were obtained by use of a quartz prism monochromatorphotomultiplier detector system with photographic recording of an oscilloscope displayed output signal. Electrically produced plasma rings were established in detonabie as well as non-reactive gases. Strong indications were observed that exothermic reactions, as evidenced by H/sub 2/O emission, proceed in H/sub 2/ + 1/2 O/sub 2/ reactant mixtures within less than one microsecond under certain initial low pressure conditions. A reaction threshold at 1 mm Hg pressure was found for the particular reaction vessel used. Timeintegrated spectrometer photos support the conclusions reached with the transient spectra analysis equipment. (auth)

Foreman, K.M.; Levy, M.E.

1962-07-30T23:59:59.000Z

437

FIFTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE  

Science Conference Proceedings (OSTI)

A series of experiments to monitor the aging performance of Viton{sup reg.} GLT O-rings used in the Model 9975 package has been ongoing for six years at the Savannah River National Laboratory. Sixty-seven mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested at nominal six month intervals to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 36 GLT O-ring fixtures at 200--350 F. Room temperature leak test failures have been experienced in 5 of the GLT O-ring fixtures aging at 300 and 350 F, and in all 3 of the GLT O-ring fixtures aging at higher temperatures. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 30--48 months, which is still bounding to O-ring temperatures during storage in KAMS. High temperature aging continues for 6 GLT-S O-ring fixtures at 200--300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 or 300 F for 19 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the O-rings displayed a compression set ranging from 51--95%. This is significantly greater than seen to date for packages inspected during KAMS field surveillance (23% average). For GLT O-rings, service life based on the room temperature leak rate criterion is comparable to that predicted by compression stress relaxation (CSR) data at higher temperatures (350--400 F). While there are no comparable failure data yet at aging temperatures below 300 F, extrapolations of the data for GLT O-rings suggests that CSR model predictions provide a conservative prediction of service life relative to the leak rate criterion. Failure data at lower temperatures is needed to verify this apparent trend. Insufficient failure data exist currently to perform a similar comparison for GLT-S O-rings. Aging and periodic leak testing will continue for the remaining fixtures.

Daugherty, W.; Hoffman, E.

2010-11-01T23:59:59.000Z

438

POWER SUPPLIES FOR THE BENDING MAGNETS OF THE BEP AND VEPP-2000 STORAGE RING  

E-Print Network (OSTI)

transformer (2) are located closely to the BEP ring. The power part of each thyristor module (Fig.2) consistsPOWER SUPPLIES FOR THE BENDING MAGNETS OF THE BEP AND VEPP-2000 STORAGE RING S.S. Vasichev, V of the collider. The beam energy change lead to the necessity to develop new power supplies for the main field

Kozak, Victor R.

439

RIGHT AND LEFT MODULES OVER THE FROBENIUS SKEW POLYNOMIAL RING IN THE F-FINITE CASE  

E-Print Network (OSTI)

, over a complete (Noetherian) local ring R of prime characteristic for which the Frobenius homomorphism between the category of left modules over the Frobenius skew polynomial ring R[x, f] that are Artinian as R-modules and the category of right R[x, f]-modules that are Noetherian as R-modules. 0

Yoshino, Yuji

440

K'-Theory of a Local Ring of Finite Cohen-Macaulay Type.  

E-Print Network (OSTI)

We study the K'-theory of a CM Henselian local ring R of finite Cohen-Macaulay type. We first describe a long exact sequence involving the groups $K_i'(R)$ and the K-groups of certain other rings, including the Auslander algebra. By examining the terms and maps in the sequence, we obtain information about K'(R).

Viraj Navkal

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Application of ring lasers to determine the directions to the poles of Earth's rotation  

Science Conference Proceedings (OSTI)

Application of a ring laser to determine the directions to the poles of Earth's rotation is considered. The maximum accuracy of determining the directions is calculated, physical and technical mechanisms that limit the accuracy are analysed, and the instrumental errors are estimated by the example of ring He - Ne lasers with Zeeman biasing. (laser applications and other topics in quantum electronics)

Golyaev, Yu D; Kolbas, Yu Yu [Open Joint-Stock Company 'M.F. Stel'makh Polyus Research and Development Institute', Moscow (Russian Federation)

2012-10-31T23:59:59.000Z

442

Tracking Stripped Proton Particles in SNS Ring Injection Momentum Dump Line  

Science Conference Proceedings (OSTI)

3D computer simulations are performed to study magnetic field distributions and particle trajectories along the SNS ring injection momentum dump line. Optical properties and transfer maps along the dump line are calculated. The stripped proton particle distributions on the dump window are analyzed. The study has provided useful information for the redesign of the SNS ring injection beam dump.

Wang, Jian-Guang [ORNL

2011-01-01T23:59:59.000Z

443

Investigation of Brazil Current rings in the confluence region Carlos A. D. Lentini,1  

E-Print Network (OSTI)

Investigation of Brazil Current rings in the confluence region Carlos A. D. Lentini,1 Gustavo J Atlantic. These fields were used to monitor the formation and characteristics of the Brazil Current warm-core anticyclonic rings shed by the first meander trough after poleward excursions of the Brazil Current (BC

444

North Brazil Current rings and transport of southern waters in a high resolution numerical  

E-Print Network (OSTI)

North Brazil Current rings and transport of southern waters in a high resolution numerical of the North Brazil Current (NBC) retroflection and North Brazil Current rings. The model mean and seasonal circulation feature near the western boundary is the North Brazil Current (NBC), which has sources

445

Possibilistic clustering approach to trackless ring Pattern Recognition in RICH counters  

Science Conference Proceedings (OSTI)

The pattern recognition problem in Ring Imaging CHerenkov (RICH) counters concerns the identification of an unknown number of rings whose centers and radii are assumed to be unknown. In this paper we present an algorithm based on the possibilistic approach ... Keywords: 07.05.Mh, 29.40.Ka, 29.85.+c, Pattern recognition, Possibilistic clustering, RICH counters

A. M. Massone; L. Studer; F. Masulli

2006-02-01T23:59:59.000Z

446

Submitted to the Astronomical Journal First Constraints on Rings in the Pluto System  

E-Print Network (OSTI)

Simple theoretical calculations have suggested that small body impacts onto Pluto’s newly discovered small satellites, Nix and Hydra, are capable of generating time-variable rings or dust sheets in the Pluto system. We present the first observational constraints on the present-day optical depth of such debris systems using HST/ACS data obtained on 2006 February 15 and 2006 March 2. We find that any Plutonian dust rings between Nix and Hydra must have optical depths of 2x10 ?5 or lower, when averaged over 1000-km radial distance scales. While usefully constraining, the derived ring optical depth limits are still a factor of four higher than those predicted by Stern et al. (2006a). Were the New Horizons spacecraft to fly through a ring system with optical depth as high as 2x10 ?5, it would collide with a significant number of potentially damaging ring particles. We therefore recommend that New Horizons cross the potential ring plane at a radial distance where dust rings are not expected due to either dynamical instability or large distance from potential sources of ring particles.

A. J. Steffl; S. A. Stern

2006-01-01T23:59:59.000Z

447

Loop Current, Rings and Related Circulation in the Gulf of Mexico: A Review of Numerical  

E-Print Network (OSTI)

3 Loop Current, Rings and Related Circulation in the Gulf of Mexico: A Review of Numerical Models of the most energetic components of the circulation in the Gulf of Mexico: the Loop Current and Loop Current the observable features of the Loop Current and rings." The Gulf of Mexico is a semi-enclosed sea that con- nects

Ezer,Tal

448

Interaction of a Warm Ring with the Western Slope in the Gulf of Mexico  

Science Conference Proceedings (OSTI)

Between November 1985 and May 1986, a warm ring encountered the western slope in the Gulf of Mexico, moved away from the slope, and began to dissipate. Before encountering the slope, the ring was quasi-circular. After encountering the slope, it ...

Fred M. Vukovich; Evans Waddell

1991-07-01T23:59:59.000Z

449

FIFTH INTERIM STATUS REPORT: MODEL 9975 PCV O-RING FIXTURE LONG-TERM LEAK PERFORMANCE  

SciTech Connect

A series of experiments to monitor the aging performance of Viton{reg_sign} GLT O-rings used in the Model 9975 package has been ongoing for six years at the Savannah River National Laboratory. Sixty-seven mock-ups of 9975 Primary Containment Vessels (PCVs) were assembled and heated to temperatures ranging from 200 to 450 F. They were leak-tested initially and have been tested at nominal six month intervals to determine if they meet the criterion of leaktightness defined in ANSI standard N14.5-97. Fourteen additional tests were initiated in 2008 with GLT-S O-rings heated to temperatures ranging from 200 to 400 F. High temperature aging continues for 36 GLT O-ring fixtures at 200-350 F. Room temperature leak test failures have been experienced in 6 of the GLT O-ring fixtures aging at 300 and 350 F, and in all 3 of the GLT O-ring fixtures aging at higher temperatures. No failures have yet been observed in GLT O-ring fixtures aging at 200 F for 30-48 months, which is still bounding to O-ring temperatures during storage in KAMS. High temperature aging continues for 6 GLT-S O-ring fixtures at 200-300 F. Room temperature leak test failures have been experienced in all 8 of the GLT-S O-ring fixtures aging at 350 and 400 F. No failures have yet been observed in GLT-S O-ring fixtures aging at 200 or 300 F for 19 months. For O-ring fixtures that have failed the room temperature leak test and been disassembled, the Orings displayed a compression set ranging from 51-95%. This is significantly greater than seen to date for packages inspected during KAMS field surveillance (23% average). For GLT O-rings, service life based on the room temperature leak rate criterion is comparable to that predicted by compression stress relaxation (CSR) data at higher temperatures (350-400 F). While there are no comparable failure data yet at aging temperatures below 300 F, extrapolations of the data for GLT O-rings suggests the CSR model predictions provide a conservative prediction of service life relative to the leak rate criterion. Failure data at lower temperatures are needed to verify this apparent trend. Insufficient failure data exist currently to perform a similar comparison for GLT-S O-rings. Aging and periodic leak testing will continue for the remaining fixtures.

Daugherty, W.; Hoffman, E.

2011-04-11T23:59:59.000Z

450

Used Fuel Disposition Campaign Phase I Ring Compression Testing of High  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Phase I Ring Compression Testing of Phase I Ring Compression Testing of High Burnup Cladding Used Fuel Disposition Campaign Phase I Ring Compression Testing of High Burnup Cladding The purpose of ring compression testing is to generate data to support the development of the technical basis for extended storage and transportation of high-burnup fuel. This report highlights the results of completed Phase I testing of high-burnup M5® cladding and the revised three-year test plan. The goal of the ring compression testing is to identify process conditions that would minimize radial-hydride formation and the corresponding DBTT of high-burnup fuel cladding and to generate data and models to support the development of the technical basis for extended storage and transportation of high-burnup fuel.

451

Vortex Ring Dyons of the SU(2) Yang-Mills-Higgs Model  

Science Conference Proceedings (OSTI)

We present an axially symmetric vortex ring dyons solutions of the SU(2) Yang-Mills-Higgs theory. These vortex rings carry electric charges that are determined by a parameter, -1{<=}{eta}{<=}1. They possess vanishing magnetic charge and are located at a ring centered around the z-axis where the Higgs field vanishes. These stationary vortex ring dyon solutions possess finite energy but they do not satisfy the first order Bogomol'nyi equations. In the Bogomol'nyi-Prasad-Sommerfield (BPS) limit where the Higgs field potential is zero, the time component of the gauge field is parallel to the Higgs field in isospace. The total energy, net electric charge and diameter of the vortex ring increase exponentially to infinity when {eta} approaches {+-}1. On the contrary, when {lambda} = 1, all these three values reach their critical value as {eta} approaches {+-}1.

Lim, Kok-Geng; Teh, Rosy; Wong, Khai-Ming [School of Physics, Universiti Sains Malaysia 11800 USM Penang (Malaysia)

2011-03-30T23:59:59.000Z

452

Analytical Approach to Eigen-Emittance Evolution in Storage Rings  

SciTech Connect

This dissertation develops the subject of beam evolution in storage rings with nearly uncoupled symplectic linear dynamics. Linear coupling and dissipative/diffusive processes are treated perturbatively. The beam distribution is assumed Gaussian and a function of the invariants. The development requires two pieces: the global invariants and the local stochastic processes which change the emittances, or averages of the invariants. A map based perturbation theory is described, providing explicit expressions for the invariants near each linear resonance, where small perturbations can have a large effect. Emittance evolution is determined by the damping and diffusion coefficients. The discussion is divided into the cases of uniform and non-uniform stochasticity, synchrotron radiation an example of the former and intrabeam scattering the latter. For the uniform case, the beam dynamics is captured by a global diffusion coefficient and damping decrement for each eigen-invariant. Explicit expressions for these quantities near coupling resonances are given. In many cases, they are simply related to the uncoupled values. Near a sum resonance, it is found that one of the damping decrements becomes negative, indicating an anti-damping instability. The formalism is applied to a number of examples, including synchrobetatron coupling caused by a crab cavity, a case of current interest where there is concern about operation near half integer {nu}{sub x}. In the non-uniform case, the moment evolution is computed directly, which is illustrated through the example of intrabeam scattering. Our approach to intrabeam scattering damping and diffusion has the advantage of not requiring a loosely-defined Coulomb Logarithm. It is found that in some situations there is a small difference between our results and the standard approaches such as Bjorken-Mtingwa, which is illustrated by comparison of the two approaches and with a measurement of Au evolution in RHIC. Finally, in combining IBS with the global invariants some general statements about IBS equilibrium can be made. Specifically, it is emphasized that no such equilibrium is possible in a non-smooth lattice, even below transition. Near enough to a synchrobetatron coupling resonance, it is found that even for a smooth ring, no IBS equilibrium occurs.

Nash, Boaz; /SLAC

2006-05-16T23:59:59.000Z

453

I1, A Tubular Thermoelectric Generator with Piled Conical Rings ...  

Science Conference Proceedings (OSTI)

Since the present tubular device is simple in structure, future works on optimal design and manufacturing will make firm steps forward to practical geothermal ...

454

A Study of the Correlation Between Electrical Resistivity and Matric Suction for Unsaturated Ash-Fall Pyroclastic Soils in the Campania Region (Southern Italy)  

E-Print Network (OSTI)

In the territory of the Campania region (southern Italy), critical rainfall events periodically trigger dangerous fast slope movements involving ashy and pyroclastic soils originated by the explosive phases of the Mt. Somma-Vesuvius volcano and deposited along the surrounding mountain ranges. In this paper, an integration of engineering-geological and geophysical measurements is presented to characterize unsaturated pyroclastic samples collected in a test area on the Sarno Mountains (Salerno and Avellino provinces, Campania region). The laboratory analyses were aimed at defining both soil water retention and electrical resistivity curves versus water content. From the matching of the experimental data, a direct relationship between electrical resistivity and matric suction is retrieved for the investigated soil horizons typical of a ash-fall pyroclastic succession. The obtained relation turns out to be helpful in characterizing soils up to close saturation, which is a critical condition for the trigger of slo...

De Vita, Pantaleone; Piegari, Ester

2011-01-01T23:59:59.000Z

455

Structure Illuminates Mechanism of Fungal Polyketide Cyclization  

NLE Websites -- All DOE Office Websites (Extended Search)

Structure Illuminates Mechanism Structure Illuminates Mechanism of Fungal Polyketide Cyclization Structure Illuminates Mechanism of Fungal Polyketide Cyclization Print Wednesday, 31 March 2010 00:00 Polyketide natural products produced by bacteria and fungi are often characterized by the presence of multiple aromatic rings that are responsible for the activity of polyketides as both beneficial antibiotic and anticancer agents and as dangerous toxic compounds, such as the highly carcinogenic aflatoxins that are produced by fungal species from the Aspergillus family of molds. Polyketide ring formation by fungal enzymes called polyketide synthases (PKSs) is mediated by the enzyme's product template (PT) domain. However, the mechanism for aromatic ring formation from a linear intermediate with high fidelity has remained unclear. To reveal the cyclization mechanism, researchers at the University of California, Irvine, and The Johns Hopkins University solved the structure of the isolated PT domain of the PKS involved in aflatoxin production (PksA) to 1.8 Å using data from ALS Beamline 8.2.2 and SSRL Beamline 9-1. The crystal structure, along with biochemical studies, provides a paradigm for polyketide cyclization by fungal PKSs, an event that is necessary for imparting biological activity to this large class of clinically relevant natural products.

456

The Darmstadt Antiproton Project (PANDA) at the High Energy Storage Ring at GSI  

DOE Green Energy (OSTI)

Recently GSI presented the plans for a major new international research facility. A key feature of this new facility will be the delivery of intense, high-quality secondary beams which embody the production of antiprotons. For the antiproton beams a 50 Tm storage ring is planned, including electron and stochastic cooling, will be able to handle antiproton beams in the momentum range from 1.5 up to 15 GeV/c. The design luminosity is 2 x 10{sup 32} cm{sup -2} s{sup -1}. The PANDA Experiment will take place at an internal target and will cover the aspects of the structure of hadrons and the properties of hadronic matter in the corresponding energy range. The main topics to be addressed are: Spectroscopy of charmonium; Search for charmed hybrids and glueballs; Interaction of open and hidden charm with nucleons and nuclei; Single and double hypernuclei; Open charm spectroscopy; CP-Violation in the charm sector; Deeply Virtual Comptom Scattering, etc. The major part of the experimental program will make use of a general purpose detector PANDA. The concept of this detector is presented.

Peters, Klaus J. (Ruhr University, Bochum, Germany)

2002-11-20T23:59:59.000Z

457

Optomechanics with molecules in a strongly pumped ring cavity  

E-Print Network (OSTI)

Cavity cooling of an atom works best on a cyclic optical transition in the strong coupling regime near resonance, where small cavity photon numbers suffice for trapping and cooling. Due to the absence of closed transitions a straightforward application to molecules fails: optical pumping can lead the particle into uncoupled states. An alternative operation in the far off-resonant regime generates only very slow cooling due to the reduced field-molecule coupling. We predict to overcome this by using a strongly driven ring-cavity operated in the sideband cooling regime. As in the optomechanical setups one takes advantage of a collectively enhanced field-molecule coupling strength using a large photon number. A linearized analytical treatment confirmed by full numerical quantum simulations predicts fast cooling despite the off-resonant small single molecule - single photon coupling. Even ground state cooling can be obtained by tuning the cavity field close to the Anti-stokes sideband for sufficiently high trapping frequency. Numerical simulations show quantum jumps of the molecules between the lowest two trapping levels, which can be be directly and continuously monitored via scattered light intensity detection.

R. J. Schulze; C. Genes; H. Ritsch

2010-03-02T23:59:59.000Z

458

Long-term stability of the APS storage ring  

SciTech Connect

The Advanced Photon Source (APS), a third-generation synchrotron light source, was commissioned in 1995 at Argonne National Laboratory and has been fully operational for beamline users since 1997. The APS storage ring can accommodate up to 68 user beamlines; about 70% of the available beamlines are currently in use by various collaborative access teams (CATs). The 7-GeV synchrotron light source produces light in the soft to hard x-ray range that is used for research in such areas as x-ray instrumentation; material, chemical and atomic sciences; biology; and geo/soil/environmental sciences. For the successful operation of an x-ray light source such as the Advanced Photon Source, the long-term stability of the concrete floor supporting the beam components and user beamlines is crucial. Settlements impact the orbit and location of the x-ray source points as well as the position of the x-ray beamlines. This paper compares the results of two successive resurveys of the APS accelerator components performed in 1995 and 1998.

Friedsam, H.; Penicka, M.; Error, J.

2000-03-16T23:59:59.000Z

459

Long-term stability of the APS storage ring  

SciTech Connect

The Advanced Photon Source (APS), a third-generation synchrotrons light source, was commissioned in 1995 at Argonne ''National Laboratory and has been fully-operational for beamline users since 1997. The APS storage ring can accommodate up to 68 user beamlines; about 70% of the available beamlines are currently in use by various collaborative access teams (CATS). The 7-GeV synchrotrons light source produces light in the soft to hard x-ray range that is used for research in such areas as x-ray instrumentation; material, chemical and atomic sciences; biology; and geo/soil/ environmental sciences. For the successful operation of an x-ray light source such as the Advanced Photon Source, the long-term stability of the concrete floor supporting the beam components and user beamlines is crucial. Settlements impact the orbit and location of the x-ray source points as well as the position of the x-ray beamlines. This paper compares the results of two successive resurveys of the APS accelerator components performed in 1995 and 1998.

Friedsam, H.; Penicka, M.; Error, J.

1999-10-26T23:59:59.000Z

460

Hybrid permanent magnet quadrupoles for the Recycler Ring at Fermilab  

Science Conference Proceedings (OSTI)

Hybrid Permanent Magnet Quadrupoles are used in several applications for the Fermilab Recycler Ring and associated beam transfer lines. Most of these magnets use a 0.6096 m long iron shell and provide integrated gradients up to 1.4 T-m/m with an iron pole tip radius of 41.6 mm. A 58.4 mm pole radius design is also required. Bricks of 25. 4 mm thick strontium ferrite supply the flux to the back of the pole to produce the desired gradients (0.6 to 2.75 T/m). For temperature compensation, Ni-Fe alloy strips are interspersed between ferrite bricks to subtract flux in a temperature dependent fashion. Adjustments of the permeance of each pole using iron between the pole and the flux return shell permits the matching of pole potentials. Magnetic potentials of the poles are adjusted to the desired value to achieve the prescribed strength and field uniformity based on rotating coil harmonic measurements. Procurement, fabrication, pole potential adjustment, and measured fields will be reported.

Brown, B.C.; Pruss, S.M.; Foster, G.W.; Glass, H.D.; Harding, D.J.; Jackson, G.R.; May, M.R.; Nicol, T.H.; Ostiguy, J.-F.; Schlabach, R.; Volk, J.T.

1997-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "unsaturated ring structures" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Investigation of Microwave Instability on Electron Storage Ring TLS  

Science Conference Proceedings (OSTI)

With the planned installation of a superconducting rf system, the new operation mode of TLS, the electron storage ring at NSRRC, is expected to double the beam intensity. Several accelerator physics topics need to be examined. Beam instability of single-bunch longitudinal microwave instability is one of these topics. We consider two approaches to measure the effective broad band impedance. We compare these measurement results with each other and to old data [Ref.1]. We calculate the threshold current of microwave instability with a mode-mixing analysis code written by Dr. K. Oide of KEK [Ref.2]. We also develop a multi-particle tracking code to simulate the instability. The results of simulation and measurement are compared and discussed. We conclude that doubling of beam current from 200 mA (1.5 mA/bunch) to 400 mA (3 mA/bunch) will not trigger the microwave instability even without a Landau cavity to lengthen the bunch. The benefit of Landau cavity is mainly for beam life time.

Wang, M.-H.; /NSRRC, Taiwan; Chao, A.; /SLAC

2005-05-17T23:59:59.000Z

462

Dissociative recombination measurements of HCl+ using an ion storage ring  

E-Print Network (OSTI)

We have measured dissociative recombination of HCl+ with electrons using a merged beams configuration at the heavy-ion storage ring TSR located at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. We present the measured absolute merged beams recombination rate coefficient for collision energies from 0 to 4.5 eV. We have also developed a new method for deriving the cross section from the measurements. Our approach does not suffer from approximations made by previously used methods. The cross section was transformed to a plasma rate coefficient for the electron temperature range from T=10 to 5000 K. We show that the previously used HCl+ DR data underestimate the plasma rate coefficient by a factor of 1.5 at T=10 K and overestimate it by a factor of 3.0 at T=300 K. We also find that the new data may partly explain existing discrepancies between observed abundances of chlorine-bearing molecules and their astrochemical models.

Novotný, O; Buhr, H; Domesle, C; Geppert, W; Grieser, M; Krantz, C; Kreckel, H; Repnow, R; Schwalm, D; Spruck, K; Stützel, J; Yang, B; Wolf, A; Savin, D W

2013-01-01T23:59:59.000Z

463

Merger and Ring Galaxy Formation Rates at z<=2  

E-Print Network (OSTI)

We compare the observed merger rate of galaxies over cosmic time and the frequency of collisional ring galaxies (CRGs), with analytic models and halo merger and collision rates from a large cosmological simulation. In the Lambda cold dark matter (LCDM) model we find that the cosmic {\\it merger fraction} does not evolve strongly between 0.2rate since z~1 might not be tied to a disappearing population of major mergers. Halos hosting massive galaxies undergo on average ~2 mergers from z~2 up to present day, reflecting the late assembly time for the massive systems and the related downsizing problem. The cosmic {\\it merger rate} declines with redshift: at the present time it is a factor of 10 lower than at z~2, in reasonable agreement with the current available data. The rate of CRG formation derived from the interactions between halo progenitors up to z=2 is found to be a good tracer of the cosmic merger rate. In the LCDM model the rate of CRGs as well as the merger rate do not scale as (1+z)^m, as suggested by previous models. Our predictions of cosmic merger and CRG rates may be applied to forthcoming surveys such as GOODS and zCOSMOS.

E. D'Onghia; M. Mapelli; B. Moore

2008-03-04T23:59:59.000Z

464

Local beam position feedback experiments on the ESRF storage ring  

SciTech Connect

This paper describes the results of local beam position feedback experiments conducted on the ESRF storage ring using digital signal processing (DSP) under the trilateral agreement of collaboration among ESRF, APS, and SPring-8. Two rf beam position monitors (BPMS) in the, upstream and downstream of the insertion device (ID) and two x-ray BPMs in the sixth cell were used to monitor the electron beam and the x-ray beam emitted from the ID, respectively. The local bump coefficients were obtained using the technique of singular value decomposition (SVD) on the global response matrix for the bump magnets and all the available BPMs outside the local bump. The local response matrix was then obtained between the two three-magnet bumps and the position monitors. The data sampling frequency was 4 kHz and a proportional, integral, and derivative (PID) controller was used. The result indicates the closed-loop feedback bandwidth close to 100 Hz and clear attenuation ({approx} {minus}40 dB) of the 7-Hz beam motion due to girder vibration resonance. Comparison of the results using the rf BPMs and x-ray BPMs will be also discussed.

Chung, Y.; Kahana, E.; Kirchman, J. [and others

1995-06-01T23:59:59.000Z

465

A Novel Crossover Operator for Genetic Algorithms: Ring Crossover  

E-Print Network (OSTI)

The genetic algorithm (GA) is an optimization and search technique based on the principles of genetics and natural selection. A GA allows a population composed of many individuals to evolve under specified selection rules to a state that maximizes the "fitness" function. In that process, crossover operator plays an important role. To comprehend the GAs as a whole, it is necessary to understand the role of a crossover operator. Today, there are a number of different crossover operators that can be used in GAs. However, how to decide what operator to use for solving a problem? A number of test functions with various levels of difficulty has been selected as a test polygon for determine the performance of crossover operators. In this paper, a novel crossover operator called 'ring crossover' is proposed. In order to evaluate the efficiency and feasibility of the proposed operator, a comparison between the results of this study and results of different crossover operators used in GAs is made through a number of te...

Kaya, Y\\ilmaz; Tek\\D{j}n, Ramazan

2011-01-01T23:59:59.000Z

466

The Effects of Variations in Buffer Gas Mixing Ratios on Commercial Carbon Dioxide Cavity Ring-Down Spectroscopy Sensors  

Science Conference Proceedings (OSTI)

Primary gas standards, gas chromatography, and frequency-stabilized cavity ring-down spectroscopy measurements have been used to assess the effect of variations in the argon mixing ratio on the CO2 mixing ratios reported by commercial cavity ring-...

D. A. Long; L. Gameson; G.-W. Truong; K. Bielska; A. Cygan; J. T. Hodges; J. R. Whetstone; R. D. van Zee

467

Compact circularly polarized slot-ring antenna and microstrip bandpass filter using triangular open-loop resonators  

E-Print Network (OSTI)

In this thesis two different research topics are undertaken, both in the area of compact RF/microwave circuits design. The first topic involves the design of a compact circularly polarized (CP) slot-ring antenna. A study of several compact CP microstrip and slotline antennas reported in the past has been carried out. In this research, a method of reducing the size of a printed slot-ring antenna is proposed. The reduction in size is achieved by introducing meandered-slot sections in the ring. Circular polarization is achieved by introducing an asymmetry, also a meandered-slot section, and feeding the antenna at an angle of 45o from the asymmetry using a microstrip feed line. The minimum axial ratio of 0.4 dB is obtained at 2.46 GHz, which is the operating frequency of the antenna. The size of the proposed antenna is reduced by about 50% compared to a conventional CP slot-ring antenna and it displays a CP bandwidth of about 2.5%. The simulated and measured results are presented, and they are in good agreement. The small size of the antenna makes it very suitable for use in modern RF/microwave wireless systems which require compact, low cost, and high performance circuits. Moreover, its CP behavior makes it more attractive for applications such as satellite communications. The second topic in the thesis involves the design of a compact microstrip bandpass filter using triangular open-loop resonators. A new compact three-pole microstrip bandpass filter using four triangular open-loop resonators is presented. A fourth resonator is placed to provide cross-coupling in the structure which gives a better skirt rejection. The measured pass-band center frequency is 2.85 GHz. The filter demonstrates about 7% bandwidth with insertion loss of less than 1 dB in the passband, a return loss of greater than 15 dB and out-of-band rejection of greater than 30 dB. The simulated and measured results are in good agreement. The proposed filter is very attractive for use in modern wireless systems which require bandpass filters having compact size, low insertion loss, high selectivity, and good out-of-band rejection.

Farooqui, Muhammad Fahad

2006-12-01T23:59:59.000Z

468

Structural morphology of acoustically levitated and heated nanosilica droplet  

SciTech Connect

We study the vaporization and precipitation dynamics of a nanosilica encapsulated water droplet by levitating it acoustically and heating it with a CO{sub 2} laser. For all concentrations, we observe three phases: solvent evaporation, surface agglomeration, and precipitation leading to bowl or ring shaped structures. At higher concentrations, ring reorientation and rotation are seen consistently. The surface temperature from an infrared camera is seen to be dependent on the final geometrical shape of the droplet and its rotation induced by the acoustic field of the levitator. With nonuniform particle distribution, these structures can experience rupture which modifies the droplet rotational speed.

Kumar, Ranganathan; Tijerino, Erick; Saha, Abhishek [Department of Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Basu, Saptarshi [Department of Mechanical Engineering, Indian Institute of Science, 560012 Bangalore (India)

2010-09-20T23:59:59.000Z

469

Adjudication Concerning 70 Additional Sputter-Ion Pumps for the Vacuum System of the Intersecting Storage Rings  

E-Print Network (OSTI)

Adjudication Concerning 70 Additional Sputter-Ion Pumps for the Vacuum System of the Intersecting Storage Rings

1968-01-01T23:59:59.000Z

470

data structure  

Science Conference Proceedings (OSTI)

Definition of data structure, possibly with links to more information and implementations. NIST. data structure. (definition). ...

2013-11-08T23:59:59.000Z

471

George Gollin, Investigation of TESLA Damping Ring Kickers using the A0 Photoinjector Beam 1 Investigation of TESLA Damping  

E-Print Network (OSTI)

George Gollin, Investigation of TESLA Damping Ring Kickers using the A0 Photoinjector Beam 1 . . .